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Sample records for negative pressure treadmill

  1. Running on a lower-body positive pressure treadmill

    DEFF Research Database (Denmark)

    Raffalt, Peter C; Hovgaard-Hansen, Line; Jensen, Bente Rona

    2013-01-01

    This study investigated maximal oxygen consumption (VO2max) and time to exhaustion while running on a lower-body positive pressure treadmill (LBPPT) at normal body weight (BW) as well as how BW support affects respiratory responses, ground reaction forces, and stride characteristics.......This study investigated maximal oxygen consumption (VO2max) and time to exhaustion while running on a lower-body positive pressure treadmill (LBPPT) at normal body weight (BW) as well as how BW support affects respiratory responses, ground reaction forces, and stride characteristics....

  2. Treadmill walking with load carriage increases aortic pressure wave reflection.

    Science.gov (United States)

    Ribeiro, Fernando; Oliveira, Nórton L; Pires, Joana; Alves, Alberto J; Oliveira, José

    2014-01-01

    The study examined the effects of treadmill walking with load carriage on derived measures of central pressure and augmentation index in young healthy subjects. Fourteen male subjects (age 31.0 ± 1.0 years) volunteered in this study. Subjects walked 10 minutes on a treadmill at a speed of 5 km/h carrying no load during one session and a load of 10% of their body weight on both upper limbs in two water carboys with handle during the other session. Pulse wave analysis was performed at rest and immediately after exercise in the radial artery of the right upper limb by applanation tonometry. The main result indicates that walking with load carriage sharply increased augmentation index at 75 bpm (-5.5 ± 2.2 to -1.4 ± 2.2% vs. -5.2 ± 2.8 to -5.5 ± 2.1%, p<0.05), and also induced twice as high increments in central pulse pressure (7.4 ± 1.5 vs. 3.1 ± 1.4 mmHg, p<0.05) and peripheral (20.5 ± 2.7 vs. 10.3 ± 2.5 mmHg, p<0.05) and central systolic pressure (14.7 ± 2.1 vs. 7.4 ± 2.0 mmHg, p<0.05). Walking with additional load of 10% of their body weight (aerobic exercise accompanied by upper limb isometric contraction) increases derived measures of central pressure and augmentation index, an index of wave reflection and arterial stiffness. Copyright © 2013 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

  3. Thermodynamics of negative absolute pressures

    International Nuclear Information System (INIS)

    Lukacs, B.; Martinas, K.

    1984-03-01

    The authors show that the possibility of negative absolute pressure can be incorporated into the axiomatic thermodynamics, analogously to the negative absolute temperature. There are examples for such systems (GUT, QCD) processing negative absolute pressure in such domains where it can be expected from thermodynamical considerations. (author)

  4. Response of the arterial blood pressure of quadriplegic patients to treadmill gait training

    Directory of Open Access Journals (Sweden)

    D.C.L. Carvalho

    2005-09-01

    Full Text Available Blood pressure pattern was analyzed in 12 complete quadriplegics with chronic lesions after three months of treadmill gait training. Before training, blood pressure values were obtained at rest, during treadmill walking and during the recovery phase. Gait training was performed for 20 min twice a week for three months. Treadmill gait was achieved using neuromuscular electrical stimulation, assisted by partial body weight relief (30-50%. After training, blood pressure was evaluated at rest, during gait and during recovery phase. Before and after training, mean systolic blood pressures and heart rates increased significantly during gait compared to rest (94.16 ± 5.15 to 105 ± 5.22 mmHg and 74.27 ± 10.09 to 106.23 ± 17.31 bpm, respectively, and blood pressure decreased significantly in the recovery phase (86.66 ± 9.84 and 57.5 ± 8.66 mmHg, respectively. After three months of training, systolic blood pressure became higher at rest (94.16 ± 5.15 mmHg before training and 100 ± 8.52 mmHg after training; P < 0.05 and during gait exercise (105 ± 5.22 mmHg before and 110 ± 7.38 mmHg after training; P < 0.05 when compared to the initial values, with no changes in heart rate. No changes occurred in blood pressure during the recovery phase, with the lower values being maintained. A drop in systolic pressure from 105 ± 5.22 to 86.66 ± 9.84 mmHg before training and from 110 ± 7.38 to 90 ± 7.38 mmHg after training was noticed immediately after exercise, thus resulting in hypotensive symptoms when chronic quadriplegics reach the sitting position from the upright position.

  5. Negative-Pressure Pulmonary Edema.

    Science.gov (United States)

    Bhattacharya, Mallar; Kallet, Richard H; Ware, Lorraine B; Matthay, Michael A

    2016-10-01

    Negative-pressure pulmonary edema (NPPE) or postobstructive pulmonary edema is a well-described cause of acute respiratory failure that occurs after intense inspiratory effort against an obstructed airway, usually from upper airway infection, tumor, or laryngospasm. Patients with NPPE generate very negative airway pressures, which augment transvascular fluid filtration and precipitate interstitial and alveolar edema. Pulmonary edema fluid collected from most patients with NPPE has a low protein concentration, suggesting hydrostatic forces as the primary mechanism for the pathogenesis of NPPE. Supportive care should be directed at relieving the upper airway obstruction by endotracheal intubation or cricothyroidotomy, institution of lung-protective positive-pressure ventilation, and diuresis unless the patient is in shock. Resolution of the pulmonary edema is usually rapid, in part because alveolar fluid clearance mechanisms are intact. In this review, we discuss the clinical presentation, pathophysiology, and management of negative-pressure or postobstructive pulmonary edema. Copyright © 2016 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

  6. Overspeed HIIT in Lower-Body Positive Pressure Treadmill Improves Running Performance.

    Science.gov (United States)

    Gojanovic, Boris; Shultz, Rebecca; Feihl, Francois; Matheson, Gordon

    2015-12-01

    Optimal high-intensity interval training (HIIT) regimens for running performance are unknown, although most protocols result in some benefit to key performance factors (running economy (RE), anaerobic threshold (AT), or maximal oxygen uptake (VO2max)). Lower-body positive pressure (LBPP) treadmills offer the unique possibility to partially unload runners and reach supramaximal speeds. We studied the use of LBPP to test an overspeed HIIT protocol in trained runners. Eleven trained runners (35 ± 8 yr, VO2max, 55.7 ± 6.4 mL·kg⁻¹·min⁻¹) were randomized to an LBPP (n = 6) or a regular treadmill (CON, n = 5), eight sessions over 4 wk of HIIT program. Four to five intervals were run at 100% of velocity at VO2max (vVO2max) during 60% of time to exhaustion at vVO2max (Tlim) with a 1:1 work:recovery ratio. Performance outcomes were 2-mile track time trial, VO2max, vVO2max, vAT, Tlim, and RE. LBPP sessions were carried out at 90% body weight. Group-time effects were present for vVO2max (CON, 17.5 vs. 18.3, P = 0.03; LBPP, 19.7 vs. 22.3 km·h⁻¹; P HIIT protocol at 100% vVO2max improves field performance, vVO2max, VO2max and submaximal HR in trained runners. Improvements are similar if intervals are run on a regular treadmill or at higher speeds on a LPBB treadmill with 10% body weight reduction. LBPP could provide an alternative for taxing HIIT sessions.

  7. Incisional Negative Pressure Wound Therapy

    DEFF Research Database (Denmark)

    Hyldig, Nana

    the rate of surgical wound infection and wound exudate post-caesarean and that wound infection had a negative impact on quality of life one month after surgery. Alongside the clinical trial, a trial-based cost-effectiveness analysis demonstrated that the treatment is cost-effective in a high......Women with a pre-gestational body mass index (BMI) above 30 kg/m2 giving birth by caesarean section are at high risk of surgical wound infection compared with women with a BMI below 30 kg/m2. Incisional Negative Pressure Wound Therapy (iNPWT) is one strategy to reduce the rate of surgical wound...... a randomised controlled trial in two tertiary and three teaching hospitals in three regions of Denmark, the Happy Belly Study, investigating the effectiveness of iNPWT in a population of obese women after caesarean section. The Happy Belly Study has demonstrated that prophylactic iNPWT significantly reduced...

  8. Muscle activation and estimated relative joint force during running with weight support on a lower-body positive pressure treadmill

    DEFF Research Database (Denmark)

    Jensen, Bente Rona; Hovgaard-Hansen, Line; Cappelen, Katrine Louise

    2016-01-01

    Running on a lower-body positive pressure (LBPP) treadmill allows effects of weight support on leg muscle activation to be assessed systematically, and has the potential to facilitate rehabilitation and prevent overloading. The aim was to study the effect of running with weight support on leg mus...

  9. Negative Pressure Wound Therapy in Maxillofacial Applications

    Directory of Open Access Journals (Sweden)

    Adam J. Mellott

    2016-09-01

    Full Text Available Negative pressure wound therapy has greatly advanced the field of wound healing for nearly two decades, by providing a robust surgical adjunct technique for accelerating wound closure in acute and chronic wounds. However, the application of negative pressure wound therapy in maxillofacial applications has been relatively under utilized as a result of the physical articulations and contours of the head and neck that make it challenging to obtain an airtight seal for different negative pressure wound therapy systems. Adapting negative pressure wound therapies for maxillofacial applications could yield significant enhancement of wound closure in maxillofacial applications. The current review summarizes the basic science underlying negative pressure wound therapy, as well as specific maxillofacial procedures that could benefit from negative pressure wound therapy.

  10. Non-invasive coronary angiography for patients with acute atypical chest pain discharged after negative screening including maximal negative treadmill stress test. A prospective study.

    Science.gov (United States)

    Bonello, L; Armero, S; Jacquier, A; Com, O; Sarran, A; Sbragia, P; Panuel, M; Arques, S; Paganelli, F

    2009-05-01

    Among patients admitted in the emergency department for acute atypical chest pain those with an acute coronary syndrome (ACS) who are mistakenly discharged home have high mortality. A recent retrospective study has demonstrated that multislice computed tomography (MSCT) coronary angiography could improve triage of these patients. We aimed to prospectively confirm these data on patients with a negative screening including maximal treadmill stress. 30 patients discharged from the emergency department after negative screening for an ACS were included. All patients underwent MSCT angiography of the coronary artery. Patients with coronary atheroma on MSCT had an invasive coronary angiography to confirm these findings. Seven patients (23%) had obstructive coronary artery disease on MSCT. Invasive coronary angiography (ICA) confirmed the diagnosis in all patients. In patients with no previously known coronary artery disease admitted to the emergency department with atypical acute chest pain and discharged after negative screening, including maximal treadmill stress test, MSCT coronary angiography is useful for the diagnosis of obstructive coronary artery disease.

  11. Negative pressure pulmonary oedema after septoplasty.

    Science.gov (United States)

    García de Hombre, Alina M; Cuffini, Alejandro; Bonadeo, Alejandro

    2013-01-01

    Negative pressure pulmonary oedema (NPPO) is an anaesthetic complication due to acute obstruction of the upper airway, whose main cause is laryngospasm. The pathophysiology involves a strong negative intrapleural pressure during inspiration against a closed glottis, which triggers excessive pressure in the pulmonary microvasculature. Although its diagnosis can be difficult, its recognition helps to minimise morbidity and mortality. This article presents a case of NPPO due to postextubation laryngospasm. Copyright © 2011 Elsevier España, S.L. All rights reserved.

  12. Ice nucleation triggered by negative pressure.

    Science.gov (United States)

    Marcolli, Claudia

    2017-11-30

    Homogeneous ice nucleation needs supercooling of more than 35 K to become effective. When pressure is applied to water, the melting and the freezing points both decrease. Conversely, melting and freezing temperatures increase under negative pressure, i.e. when water is stretched. This study presents an extrapolation of homogeneous ice nucleation temperatures from positive to negative pressures as a basis for further exploration of ice nucleation under negative pressure. It predicts that increasing negative pressure at temperatures below about 262 K eventually results in homogeneous ice nucleation while at warmer temperature homogeneous cavitation, i. e. bubble nucleation, dominates. Negative pressure occurs locally and briefly when water is stretched due to mechanical shock, sonic waves, or fragmentation. The occurrence of such transient negative pressure should suffice to trigger homogeneous ice nucleation at large supercooling in the absence of ice-nucleating surfaces. In addition, negative pressure can act together with ice-inducing surfaces to enhance their intrinsic ice nucleation efficiency. Dynamic ice nucleation can be used to improve properties and uniformity of frozen products by applying ultrasonic fields and might also be relevant for the freezing of large drops in rainclouds.

  13. Negative Ions in low pressure discharges

    NARCIS (Netherlands)

    Stoffels - Adamowicz, E.; Stoffels, W.W.; Vender, D.; Haverlag, M.; Kroesen, G.M.W.; Hoog, de F.J.

    1995-01-01

    Several aspects of negative ions in low pressure discharges are treated. The elementary processes, in which negative ions are produced and destroyed, are summarized. The influence of negative ions on plasma operation is analyzed in terms of transport equations. It is shown that diffusion, electric

  14. Exaggerated Exercise Blood Pressure Response During Treadmill Testing as a Predictor of Future Hypertension in Men: A Longitudinal Study.

    Science.gov (United States)

    Jae, Sae Young; Franklin, Barry A; Choo, Jina; Choi, Yoon-Ho; Fernhall, Bo

    2015-11-01

    The purpose of this study was to evaluate receiver operating characteristic curves to identify optimal cutoff values of exercise systolic blood pressure (SBP) using both peak SBP and relative SBP (peak SBP minus resting SBP) as predictors of future hypertension (HTN). Participants were 3,742 healthy normotensive men who underwent symptom-limited treadmill testing at baseline. Incident HTN was defined as SBP/diastolic blood pressure greater than 140/90 mm Hg and/or diagnosed HTN by a physician. During an average 5-year follow-up, 364 (9.7%) new cases of HTN were observed. The most discriminatory cutoff values for peak SBP and relative SBP for predicting incident HTN were 181 mm Hg (areas under the curve (AUC) = 0.644, sensitivity = 54%, and specificity = 69%) and 52 mm Hg (AUC = 0.549, sensitivity = 64.3%, and specificity = 44.6%), respectively. Participants with peak SBP greater than 181 mm Hg and relative SBP greater than 52 mm Hg had 1.54-fold (95% CI: 1.23-1.93) and 1.44-fold (95% CI: 1.16-1.80) risks of developing HTN after adjusting for potential confounding variables. When these 2 variables were entered simultaneously into the Cox proportional hazards regression model with adjustment for potential confounding variables, only peak SBP (relative risk: 1.39, 95% CI: 1.02-1.89) was a predictor of the development of HTN. The most accurate discriminators for peak and relative SBP during treadmill exercise testing to predict incident HTN were greater than 181 and 52 mm Hg, respectively, in normotensive men. A peak SBP greater than 181 mm Hg during treadmill exercise testing may provide a useful predictor for the development of HTN in clinical practice. © American Journal of Hypertension, Ltd 2015. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  15. Double product response and diastolic blood pressure in treadmill, stationary bicycle and muscular circuit exercises

    Directory of Open Access Journals (Sweden)

    Elmiro Santos Resende

    2006-06-01

    Full Text Available Among the various causes for cardiovascular problems affecting the world population nowadays, the most relevant risk factors is sedentary lifestyle. Many studies have been carried out to analyse and elucidate main adaptations on the cardiovascular system stimulated by different sorts of exercises.In this way, this study had aimed at comparing the acute response of double product (DP and diastolic blood pressure (DBP after treadmill (TRM, stationary bicycle (BIC or muscle circuit training (MCT exercises. Nine individuals (6 women and 3 men exercised at 60% of heart rate reserve (HRR on the TRM and BIC and at 60% of one repetition maximum (1RM in MCT. The results showed that pre- and post-effort DP were significantly difference in all three exercises. However, DP did not differ among exercise types. The hypotensive DBP pos-effort response was greater in MCT. According to the results, it was concluded that there is no difference on the heart work demand rate estimated by DP among the three exercises and MCT at 60% 1RM provokes a greater hypotensive DBP post-effort response. RESUMO Entre as diversas causas de problemas cardiovasculares que afetam a população mundial, na atualidade, o sedentarismo é apontado como um dos fatores de risco mais relevantes. Vários estudos têm se preocupado em analisar e esclarecer as principais adaptações provocadas pelos diferentes tipos de exercícios sobre o sistema cardiovascular. Seguindo esta linha o presente trabalho teve como objetivo analisar e comparar a resposta aguda do duplo produto (DP e a pressão arterial diastólica (PAD em exercício de esteira, bicicleta estacionária e circuito na musculação. Foram avaliados nove indivíduos sendo seis mulheres e três homens, na esteira, a 60% da freqüência cardíaca de reserva (FCR, na bicicleta estacionária, a 60% FCR e circuito de musculação a 60% de 1 repetição máxima (1RM. Os resultados encontrados apresentaram diferença significativa do DP pr

  16. Double product response and diastolic blood pressure in treadmill, stationary bicycle and muscular circuit exercises

    Directory of Open Access Journals (Sweden)

    Leandro Teixeira Paranhos Lopes

    2006-08-01

    Full Text Available Among the various causes for cardiovascular problems affecting the world population nowadays, the most relevant risk factors is sedentary lifestyle. Many studies have been carried out to analyse and elucidate main adaptations on the cardiovascular system stimulated by different sorts of exercises.In this way, this study had aimed at comparing the acute response of double product (DP and diastolic blood pressure (DBP after treadmill (TRM, stationary bicycle (BIC or muscle circuit training (MCT exercises. Nine individuals (6 women and 3 men exercised at 60% of heart rate reserve (HRR on the TRM and BIC and at 60% of one repetition maximum (1RM in MCT. The results showed that pre- and post-effort DP were significantly difference in all three exercises. However, DP did not differ among exercise types. The hypotensive DBP pos-effort response was greater in MCT. According to the results, it was concluded that there is no difference on the heart work demand rate estimated by DP among the three exercises and MCT at 60% 1RM provokes a greater hypotensive DBP post-effort response. . Resumo Entre as diversas causas de problemas cardiovasculares que afetam a população mundial, na atualidade, o sedentarismo é apontado como um dos fatores de risco mais relevantes. Vários estudos têm se preocupado em analisar e esclarecer as principais adaptações provocadas pelos diferentes tipos de exercícios sobre o sistema cardiovascular. Seguindo esta linha o presente trabalho teve como objetivo analisar e comparar a resposta aguda do duplo produto (DP e a pressão arterial diastólica (PAD em exercício de esteira, bicicleta estacionária e circuito na musculação. Foram avaliados nove indivíduos sendo seis mulheres e três homens, na esteira, a 60% da freqüência cardíaca de reserva (FCR, na bicicleta estacionária, a 60% FCR e circuito de musculação a 60% de 1 repetição máxima (1RM. Os resultados encontrados apresentaram diferença significativa do DP

  17. Variations of Negative Pressure Wound Therapy

    African Journals Online (AJOL)

    a living reaction which serves to eradicate necrotic tissue and suppress bacterial propagation. In order to gain maximum advantages from NPWT, not only the negative pressure environment, but also the selection of the most suitable dressing material will be necessary. Regarding the treatment of diabetic foot ulcers, there.

  18. Clinical value and severity of myocardial perfusion defects in asymptomatic diabetic patients with negative or weakly positive exercise treadmill test

    International Nuclear Information System (INIS)

    Zakavi, Seyed Rasoul; Taherpour, Mehdi; Moossavi, Zohreh; Sadeghi, Ramin; Kakhki, Vahidreza Dabbagh; Rokni, Haleh

    2013-01-01

    Although coronary artery disease (CAD) is the leading cause of death in type 2 diabetic patients, it is frequently asymptomatic. Myocardial perfusion imaging (MPI) is reported to show ischemia in a significant number of asymptomatic diabetic patients. We studied the prevalence and severity of myocardial perfusion defects in asymptomatic diabetic patients and its clinical impact. One hundred thirty consecutive asymptomatic patients, aged 35-65 years with type 2 diabetes mellitus and with no history of CAD and no cardiac symptoms were recruited in the study. Echocardiography, electrocardiography (ECG), routine laboratory tests and exercise treadmill test (ETT) were performed and patients with weakly positive or negative ETT underwent Dipyridamole MPI. Patients with positive ETT were referred to coronary angiography. Patients were followed for at least 17 months (mean 21.7 months) and any cardiac event was recorded. We studied 81 female and 49 male patients with mean age of 51.8 years. Negative, weakly positive and positive ETT result was noted in 74.3%, 15% and 10.7% respectively. 75% of patients with positive ETT had coronary artery disease in angiography. Gated myocardial perfusion SPECT was done in 106 patients. MPI showed reversible defect in 26.9% of the patients with a mean summed stress score of 3.3±1.8. Follow up completed in 112 patients and only one patient with abnormal MPI underwent coronary angiography followed by PTCA. No cardiac death, MI, UA or hospital admission occurred among our patients during follow up (17-26 months). Mean stress end diastolic volume (EDV) was significantly higher in patients with reversible defect compared to patients without reversible defect based on MPI findings (62.0±31.6 Vs 48.5±18.4 ml, P=0.04). Blood glucose and HbA1c were significantly higher in patients with ischemia compared to patients without ischemia (P<0.05). Meanwhile the ratio of TG to HDL was 6.06±3.2 in ischemic patients compared to 4.8±2.3 in normal

  19. Alterations in the Rate of Limb Movement Using a Lower Body Positive Pressure Treadmill Do Not Influence Respiratory Rate or Phase III Ventilation

    OpenAIRE

    Michael J. Buono; Marissa Burnsed-Torres; Bethany Hess; Kristine Lopez; Catherine Ortiz; Ariel Girodo; Karen Lolli; Brett Bloom; David Bailey; Fred W. Kolkhorst

    2015-01-01

    The purpose of this study was to determine the effect of alterations in rate of limb movement on Phase III ventilation during exercise, independent of metabolic rate, gait style, and treadmill incline. Subjects completed five submaximal exercise bouts on a lower body positive pressure treadmill (AlterG P 200). The percent body weight for the five exercise bouts was 100, 87, 75, 63, and 50% and each was matched for carbon dioxide production (V CO2 ). Naturally, to match the V CO2 while reducin...

  20. Negative pressure wound therapy and nurse education.

    Science.gov (United States)

    Cray, Amy

    2017-08-10

    there can be serious consequences for patients if negative pressure wound therapy (NPWT) is performed incorrectly and patient safety must be paramount. The existing literature was found to mainly concentrate on the use of the technology from the patient perspective. This article examines the opinions of nurses who apply the therapy. five staff nurses from different areas with differing experience levels were interviewed in a semi-structured manner. The transcribed interviews were coded, sorted into themes and analysed. the themes were: enhancing knowledge and understanding, managing problematic pumps, formalised and interactive training, and efficacy and healing. There was a lack of standardised training provided for the nurses interviewed. Overall the nurses were aware of the basic evidence behind the treatment but would have liked additional support in this area as well as some practical, less pressured training. This complements the existing literature. nurses are expected to learn difficult and highly specialised skills quickly within a busy ward environment, often with no prior training or preparation. As things can go wrong, with the potential for patient harm, it is vital that nurses get these skills right first time, but it is difficult to do this in a practical, fast and cost-effective way. There is scope for future research in the area and perhaps the development of an online training tool to assist nurses in understanding and undertaking a new procedure.

  1. Homocysteine, visceral adiposity-related novel cardiometabolic risk factors, and exaggerated blood pressure response to the exercise treadmill test.

    Science.gov (United States)

    Türker Duyuler, Pinar; Duyuler, Serkan; Demir, Mevlüt; Uçar Elalmiş, Özgül; Güray, Ümit; İleri, Mehmet

    2017-12-01

    Exaggerated blood pressure response to exercise is a risk factor for the development of future hypertension. In this study, we aimed to investigate the association between homocysteine, epicardial fat thickness, nonalcoholic hepatic steatosis, and exaggerated blood pressure response to exercise. We included 44 normotensive and 40 patients with exaggerated blood pressure response to exercise who have normal resting blood pressure and without a previous diagnosis of hypertension. All patients underwent treadmill exercise test and clinical, ultrasonographic, and echocardiographic evaluation. Exaggerated blood pressure response to exercise is defined as peak exercise systolic blood pressure of at least 210 mmHg in men and at least 190 mmHg in women. Homocysteine and other biochemical parameters were determined with standardized automated laboratory tests. Mean age of all participants is 47.9±8.5 years, and 36 of 84 participants were female. The frequency of diabetes mellitus in both groups was similar (P=0.250). Homeostasis model assessment index-insulin resistance had a statistically insignificant trend to be higher in a patient with exercise hypertension (P=0.058). The nonalcoholic fatty liver was more frequent in patients with exercise hypertension (13.6 vs. 47.5%, P=0.002). Epicardial fat thickness was increased in patients with exercise hypertension (5.5±1.5 vs. 7.3±1.1 mm; P=0.001). However, homocysteine levels did not significantly differ between normotensive and exercise hypertensive patients [12.3 μmol/l (5.7-16.9 μmol/l) vs. 13 μmol/l (5.9-28.3 μmol/l); P=0.883]. In our study, homocysteine levels were not associated with exaggerated blood pressure response to exercise; however, fatty liver and epicardial fat thickness as visceral adiposity-related cardiometabolic risk factors were significantly related with exaggerated blood pressure response to exercise in patients without a previous diagnosis of hypertension.

  2. outcome of foam versus gauze dressings in negative pressure

    African Journals Online (AJOL)

    2013-07-30

    Jul 30, 2013 ... Negative pressure wound therapy (NPWT) is one of .... Presence of necrotic material. If present ..... an alternative dressing interface and other vacuum sources .... edge micro-vascular blood flow: Effects of negative pressure ...

  3. Evaluation of continuous and intermittent myocardial topical negative pressure

    DEFF Research Database (Denmark)

    Lindstedt, Sandra; Malmsjö, Malin; Gesslein, Bodil

    2008-01-01

    Topical negative pressure, commonly used in wound therapy, has been shown to increase blood flow and stimulate angiogenesis in subcutaneous tissue and skeletal muscle. In wound therapy, intermittent negative pressure is often preferred to continuous negative pressure as tissue exposed to intermit...

  4. Alterations in the rate of limb movement using a lower body positive pressure treadmill do not influence respiratory rate or phase III ventilation.

    Science.gov (United States)

    Buono, Michael J; Burnsed-Torres, Marissa; Hess, Bethany; Lopez, Kristine; Ortiz, Catherine; Girodo, Ariel; Lolli, Karen; Bloom, Brett; Bailey, David; Kolkhorst, Fred W

    2015-01-01

    The purpose of this study was to determine the effect of alterations in rate of limb movement on Phase III ventilation during exercise, independent of metabolic rate, gait style, and treadmill incline. Subjects completed five submaximal exercise bouts on a lower body positive pressure treadmill (AlterG P 200). The percent body weight for the five exercise bouts was 100, 87, 75, 63, and 50% and each was matched for carbon dioxide production (V CO2 ). Naturally, to match the V CO2 while reducing the body weight up to 50% of normal required a significant increase in the treadmill speed from 3.0 ± 0.1 to 4.1 ± 0.2 mph, which resulted in a significant (P body weight) to 133 ± 6 at 4.1 mph (i.e., 50% of body weight). The most important finding was that significant increases in step frequency did not significantly alter minute ventilation or respiratory rate. Such results do not support an important role for the rate of limb movement in Phase III ventilation during submaximal exercise, when metabolic rate, gait style, and treadmill incline are controlled.

  5. Alterations in the Rate of Limb Movement Using a Lower Body Positive Pressure Treadmill Do Not Influence Respiratory Rate or Phase III Ventilation

    Directory of Open Access Journals (Sweden)

    Michael J. Buono

    2015-01-01

    Full Text Available The purpose of this study was to determine the effect of alterations in rate of limb movement on Phase III ventilation during exercise, independent of metabolic rate, gait style, and treadmill incline. Subjects completed five submaximal exercise bouts on a lower body positive pressure treadmill (AlterG P 200. The percent body weight for the five exercise bouts was 100, 87, 75, 63, and 50% and each was matched for carbon dioxide production (VCO2. Naturally, to match the VCO2 while reducing the body weight up to 50% of normal required a significant increase in the treadmill speed from 3.0±0.1 to 4.1±0.2 mph, which resulted in a significant (P<0.05 increase in the mean step frequency (steps per minute from 118±10 at 3 mph (i.e., 100% of body weight to 133±6 at 4.1 mph (i.e., 50% of body weight. The most important finding was that significant increases in step frequency did not significantly alter minute ventilation or respiratory rate. Such results do not support an important role for the rate of limb movement in Phase III ventilation during submaximal exercise, when metabolic rate, gait style, and treadmill incline are controlled.

  6. Capillarity Induced Negative Pressure of Water Plugs in Nanochannels

    NARCIS (Netherlands)

    Tas, Niels Roelof; Mela, P.; Kramer, Tobias; Berenschot, Johan W.; van den Berg, Albert

    2003-01-01

    We have found evidence that water plugs in hydrophilic nanochannels can be at significant negative pressure due to tensile capillary forces. The negative pressure of water plugs in nanochannels induces bending of the thin channel capping layer, which results in a visible curvature of the liquid

  7. An Affordable Custom-Built Negative Pressure Wound Therapy

    African Journals Online (AJOL)

    Negative pressure wound therapy (NPWT) is a well- established modality for treating complex wounds (1). ... a negative pressure which causes a characteristic shrinking of the gauze, indicating that the device ... We have applied this simplified technique of NPWT in patients with diabetic foot ulcers and open fractures.

  8. 21 CFR 868.5935 - External negative pressure ventilator.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false External negative pressure ventilator. 868.5935 Section 868.5935 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... ventilator. (a) Identification. An external negative pressure ventilator (e.g., iron lung, cuirass) is a...

  9. Pressure Field Around Underwater Negative Streamers

    Czech Academy of Sciences Publication Activity Database

    Hoffer, Petr; Koláček, Karel; Lukeš, Petr; Stelmashuk, Vitaliy

    2015-01-01

    Roč. 43, č. 5 (2015), s. 1787-1792 ISSN 0093-3813 R&D Projects: GA ČR(CZ) GA15-12987S Grant - others:Rada Programu interní podpory projektů mezinárodní spolupráce AV ČR(CZ) M100431203 Program:M Institutional support: RVO:61389021 Keywords : Interferometry * plasma generation * pressure measurement * water Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.958, year: 2015

  10. SIMULATION OF NEGATIVE PRESSURE WAVE PROPAGATION IN WATER PIPE NETWORK

    Directory of Open Access Journals (Sweden)

    Tang Van Lam

    2017-11-01

    Full Text Available Subject: factors such as pipe wall roughness, mechanical properties of pipe materials, physical properties of water affect the pressure surge in the water supply pipes. These factors make it difficult to analyze the transient problem of pressure evolution using simple programming language, especially in the studies that consider only the magnitude of the positive pressure surge with the negative pressure phase being neglected. Research objectives: determine the magnitude of the negative pressure in the pipes on the experimental model. The propagation distance of the negative pressure wave will be simulated by the valve closure scenarios with the help of the HAMMER software and it is compared with an experimental model to verify the quality the results. Materials and methods: academic version of the Bentley HAMMER software is used to simulate the pressure surge wave propagation due to closure of the valve in water supply pipe network. The method of characteristics is used to solve the governing equations of transient process of pressure change in the pipeline. This method is implemented in the HAMMER software to calculate the pressure surge value in the pipes. Results: the method has been applied for water pipe networks of experimental model, the results show the affected area of negative pressure wave from valve closure and thereby we assess the largest negative pressure that may appear in water supply pipes. Conclusions: the experiment simulates the water pipe network with a consumption node for various valve closure scenarios to determine possibility of appearance of maximum negative pressure value in the pipes. Determination of these values in real-life network is relatively costly and time-consuming but nevertheless necessary for identification of the risk of pipe failure, and therefore, this paper proposes using the simulation model by the HAMMER software. Initial calibration of the model combined with the software simulation results and

  11. The phase diagram of water at negative pressures: virtual ices.

    Science.gov (United States)

    Conde, M M; Vega, C; Tribello, G A; Slater, B

    2009-07-21

    The phase diagram of water at negative pressures as obtained from computer simulations for two models of water, TIP4P/2005 and TIP5P is presented. Several solid structures with lower densities than ice Ih, so-called virtual ices, were considered as possible candidates to occupy the negative pressure region of the phase diagram of water. In particular the empty hydrate structures sI, sII, and sH and another, recently proposed, low-density ice structure. The relative stabilities of these structures at 0 K was determined using empirical water potentials and density functional theory calculations. By performing free energy calculations and Gibbs-Duhem integration the phase diagram of TIP4P/2005 was determined at negative pressures. The empty hydrates sII and sH appear to be the stable solid phases of water at negative pressures. The phase boundary between ice Ih and sII clathrate occurs at moderate negative pressures, while at large negative pressures sH becomes the most stable phase. This behavior is in reasonable agreement with what is observed in density functional theory calculations.

  12. Responses to negative pressure surrounding the neck in anesthetized animals.

    Science.gov (United States)

    Wolin, A D; Strohl, K P; Acree, B N; Fouke, J M

    1990-01-01

    Continuous positive pressure applied at the nose has been shown to cause a decrease in upper airway resistance. The present study was designed to determine whether a similar positive transmural pressure gradient, generated by applying a negative pressure at the body surface around the neck, altered upper airway patency. Studies were performed in nine spontaneously breathing anesthetized supine dogs. Airflow was measured with a pneumotachograph mounted on an airtight muzzle placed over the nose and mouth of each animal. Upper airway pressure was measured as the differential pressure between the extrathoracic trachea and the inside of the muzzle. Upper airway resistance was monitored as an index of airway patency. Negative pressure (-2 to -20 cmH2O) was applied around the neck by using a cuirass extending from the jaw to the thorax. In each animal, increasingly negative pressures were transmitted to the airway wall in a progressive, although not linear, fashion. Decreasing the pressure produced a progressive fall in upper airway resistance, without causing a significant change in respiratory drive or respiratory timing. At -5 cmH2O pressure, there occurred a significant fall in upper airway resistance, comparable with the response of a single, intravenous injection of sodium cyanide (0.5-3.0 mg), a respiratory stimulant that produces substantial increases in respiratory drive. We conclude that upper airway resistance is influenced by the transmural pressure across the airway wall and that such a gradient can be accomplished by making the extraluminal pressure more negative.(ABSTRACT TRUNCATED AT 250 WORDS)

  13. Negative pressure pulmonary edema revisited: Pathophysiology and review of management

    Directory of Open Access Journals (Sweden)

    Balu Bhaskar

    2011-01-01

    Full Text Available Negative pressure pulmonary edema (NPPE is a dangerous and potentially fatal condition with a multifactorial pathogenesis. Frequently, NPPE is a manifestation of upper airway obstruction, the large negative intrathoracic pressure generated by forced inspiration against an obstructed airway is thought to be the principal mechanism involved. This negative pressure leads to an increase in pulmonary vascular volume and pulmonary capillary transmural pressure, creating a risk of disruption of the alveolar-capillary membrane. The early detection of the signs of this syndrome is vital to the treatment and to patient outcome. The purpose of this review is to highlight the available literature on NPPE, while probing the pathophysiological mechanisms relevant in both the development of this condition and that involved in its resolution.

  14. Tissue oxygen partial pressure in the tibialis anterior muscle in patients with claudication before, during and after a two-stage treadmill stress test.

    Science.gov (United States)

    Jung, F; Krüger, A; Pindur, G; Sternitzky, R; Franke, R P; Gori, T

    2014-01-01

    The role of the microcirculation in the pathophysiology and symptoms of peripheral arterial obliterative disease (PAOD) has been progressively emphasized during the past decades. Under resting conditions, already, the tissue oxygen partial pressure in the m. tibialis anterior (pO2im) is reduced to about 50% compared to healthy subjects. In the framework of this study the pO2im of patients with PAOD stage II according to Fontaine (n=16) in the m. tibialis anterior was measured under resting conditions and during walking on a treadmill in comparison to healthy subjects (n=10). Under resting conditions the pO2im only marginally differed between PAOD patients and healthy subjects. But during exercise the pO2im dropped significantly more severely in PAOD patients and a return to baseline values could only be reached when the treadmill was stopped and the patients stood still. The pO2im minima correlated clearly with the clinical symptom of calf pain. The data revealed that the pO2im values were lower in PAOD patients and dropped significantly faster during walking compared to the pO2im values in healthy subjects. The pO2im decrease correlated with the calf pain occurring when the pO2im values approached or fell below 10 mmHg.

  15. Short-term step-to-step correlation in plantar pressure distributions during treadmill walking, and implications for footprint trail analysis.

    Science.gov (United States)

    Pataky, Todd C; Savage, Russell; Bates, Karl T; Sellers, William I; Crompton, Robin H

    2013-09-01

    The gait cycle is continuous, but for practical reasons one is often forced to analyze one or only a few adjacent cycles, for example in non-treadmill laboratory investigations and in fossilized footprint analysis. The nature of variability in long-term gait cycle dynamics has been well-investigated, but short-term variability, and specifically correlation, which are highly relevant to short gait bouts, have not. We presently tested for step-to-step autocorrelation in a total of 5243 plantar pressure (PP) distributions from ten subjects who walked at 1.1m/s on an instrumented treadmill. Following spatial foot alignment, data were analyzed both from three points of interest (POI): heel, central metatarsals, and hallux, and for the foot surface as a whole, in a mass-univariate manner. POI results revealed low average step-to-step autocorrelation coefficients (r=0.327±0.094; mean±st. dev.). Formal statistical testing of the whole-foot r distributions reached significance over an average of only 0.42±0.52% of the foot's surface, even for a highly conservative uncorrected threshold of p<0.05. The common assumption, that short gait bouts consist of independent cycles, is therefore not refuted by the present PP results. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. A prospective comparison of pedal ergometry with conventional treadmill testing in the investigation of lower extremity pain.

    LENUS (Irish Health Repository)

    Manning, B J

    2012-02-03

    BACKGROUND: Investigation of lower extremity pain is compromised by comorbid disorders that may interfere with conventional testing. AIMS: To compare pedal ergometry with conventional treadmill testing. METHODS: A prospective study was performed where patients presenting with a diagnosis of intermittent claudication were assessed by both methods of testing. RESULTS: Of 78 patients studied with both tests, no exercise-induced ankle pressure changes occurred in 26, two were unable to complete either test despite normal pressure measurements, while 24 had exercise-induced pressure drop detected by both tests. Of patients who completed pedal ergometry, 21 were unable to complete the treadmill test, 14 of whom had negative ergometry, while seven had a pressure drop detected by pedal ergometry. Three had pressure changes with pedal ergometry, but not with treadmill testing and two had pressure changes on the treadmill not reproduced by pedal ergometry. CONCLUSIONS: Pedal ergometer is more sensitive than treadmill testing in detecting arterial insufficiency, as indicated by a 20% or greater fall in ankle pressure, and more suitable in a subgroup of patients unable to tolerate conventional treadmill testing.

  17. Negative pressure characteristics of an evaporating meniscus at nanoscale

    Directory of Open Access Journals (Sweden)

    Maroo Shalabh

    2011-01-01

    Full Text Available Abstract This study aims at understanding the characteristics of negative liquid pressures at the nanoscale using molecular dynamics simulation. A nano-meniscus is formed by placing liquid argon on a platinum wall between two nano-channels filled with the same liquid. Evaporation is simulated in the meniscus by increasing the temperature of the platinum wall for two different cases. Non-evaporating films are obtained at the center of the meniscus. The liquid film in the non-evaporating and adjacent regions is found to be under high absolute negative pressures. Cavitation cannot occur in these regions as the capillary height is smaller than the critical cavitation radius. Factors which determine the critical film thickness for rupture are discussed. Thus, high negative liquid pressures can be stable at the nanoscale, and utilized to create passive pumping devices as well as significantly enhance heat transfer rates.

  18. Negative pressure dressing combined with a traditional approach for ...

    African Journals Online (AJOL)

    2011-07-21

    Jul 21, 2011 ... Deep burns of the calvarium due to high-voltage electrical current present serious therapeutic challenges in the healing. In this study, as an alternative approach to the treatment of burned skull, negative pressure dressing is used to facilitate separation of the necrotic bones from healthy margins of the ...

  19. Negative interstitial pressure in the peritendinous region during exercise

    DEFF Research Database (Denmark)

    Langberg, Henning; Skovgaard, D; Bülow, J

    1999-01-01

    of these observations, microdialysis was performed in the peritendinous region with a colloid osmotic active substance (Dextran 70, 0.1 g/ml) added to the perfusate with the aim of counteracting the negative tissue pressure. Dialysate volume was found to be fully restored (100 +/- 4%) during exercise. It is concluded...

  20. The use of negative pressure wave treatment in athlete recovery ...

    African Journals Online (AJOL)

    Background: Athletes need to recover fully to maximise performance in competitive sport. Athletes who replenish more quickly and more efficiently are able to train harder and more intensely. Elite athletes subjectively report positive results using lower body negative pressure (LBNP) treatment as an alternate method for ...

  1. Controlling a negative loaded hydraulic cylinder using pressure feedback

    DEFF Research Database (Denmark)

    Hansen, M.R.; Andersen, T.O.

    2010-01-01

    This paper is concerned with the inherent oscillatory nature of pressure compensated velocity control of a hydraulic cylinder subjected to a negative load and suspended by means of an over-center valve. Initially, a linearized stability analysis of such a hydraulic circuit is carried out clearly ...... in a nonlinear time domain simulation model validating the linear stability analysis....

  2. Cardiovascular response during submaximal underwater treadmill exercise in stroke patients.

    Science.gov (United States)

    Yoo, Jeehyun; Lim, Kil-Byung; Lee, Hong-Jae; Kwon, Yong-Geol

    2014-10-01

    To evaluate the cardiovascular response during head-out water immersion, underwater treadmill gait, and land treadmill gait in stroke patients. Ten stroke patients were recruited for underwater and land treadmill gait sessions. Each session was 40 minutes long; 5 minutes for standing rest on land, 5 minutes for standing rest in water or on treadmill, 20 minutes for treadmill walking in water or on land, 5 minutes for standing rest in water or on treadmill, and 5 minutes for standing rest on land. Blood pressure (BP) and heart rate (HR) were measured during each session. In order to estimate the cardiovascular workload and myocardial oxygen demand, the rate pressure product (RPP) value was calculated by multiplying systolic BP (SBP) by HR. SBP, DBP, mean BP (mBP), and RPP decreased significantly after water immersion, but HR was unchanged. During underwater and land treadmill gait, SBP, mBP, DBP, RPP, and HR increased. However, the mean maximum increases in BP, HR and RPP of underwater treadmill walking were significantly lower than that of land treadmill walking. Stroke patients showed different cardiovascular responses during water immersion and underwater gait as opposed to standing and treadmill-walking on land. Water immersion and aquatic treadmill gait may reduce the workload of the cardiovascular system. This study suggested that underwater treadmill may be a safe and useful option for cardiovascular fitness and early ambulation in stroke rehabilitation.

  3. Proposed application of lower body negative pressure to cardiology

    Science.gov (United States)

    Schmidt, E. V.; Debusk, R. F.; Popp, R. L.

    1975-01-01

    Potential medical applications are presented of lower body negative pressure to the evaluation and treatment of cardiac patients. The essential features of an LBNP unit and the basic cardiovascular physiology of lower body negative pressure (LBNP) testing are described. Some of the results of previous spaceflight experiences and bedrest studies are summarized. The deconditioning effects of weightlessness experienced by orbiting astronauts are compared with the effects of bedrest restrictions prescribed for convalescing cardiac patients. The potential of LBNP for evaluating both pharmacological and physical activity regimens was examined, particularly in relation to post-myocardial infarction and coronary artery bypass patients. Applications of LBNP to the cardiac catheterization laboratory and the out-patient follow-up of cardiac patients are proposed.

  4. Rapid Onset Acute Epiglottitis Leading to Negative Pressure Pulmonary Edema

    Directory of Open Access Journals (Sweden)

    V Saraswat

    2007-01-01

    Full Text Available Pulmonary edema is a potentially life-threatening complication of acute airway obstruction. It develops rapidly, without warning, in young healthy individuals. Two forms of post-obstructive pulmonary edema (POPE (also known as negative pressure pulmonary edema, NPPE have been identified. POPE I follows sudden, severe upper airway obstruction. POPE II occurs following surgical relief of chronic upper airway obstruction. Treatment for both is supportive. Full and rapid recovery can be expected with appropriate management. A case report of a middle aged man with acute onset epiglottitis who developed negative pressure pulmonary edema after intubation is presented. The report includes a brief discussion on etiology, clinical features and management dilemma of acute upper airway obstruction.

  5. Rapid Onset Acute Epiglottitis Leading to Negative Pressure Pulmonary Edema

    OpenAIRE

    V Saraswat; P V Madhu; Suresh S Kumar

    2007-01-01

    Pulmonary edema is a potentially life-threatening complication of acute airway obstruction. It develops rapidly, without warning, in young healthy individuals. Two forms of post-obstructive pulmonary edema (POPE) (also known as negative pressure pulmonary edema, NPPE) have been identified. POPE I follows sudden, severe upper airway obstruction. POPE II occurs following surgical relief of chronic upper airway obstruction. Treatment for both is supportive. Full and rapid recovery can be expecte...

  6. Negative-pressure wound therapy with instillation: international consensus guidelines.

    Science.gov (United States)

    Kim, Paul J; Attinger, Christopher E; Steinberg, John S; Evans, Karen K; Lehner, Burkhard; Willy, Christian; Lavery, Larry; Wolvos, Tom; Orgill, Dennis; Ennis, William; Lantis, John; Gabriel, Allen; Schultz, Gregory

    2013-12-01

    Negative-pressure wound therapy with instillation is increasingly utilized as an adjunct therapy for a wide variety of wounds. Despite its growing popularity, there is a paucity of evidence and lack of guidance to provide effective use of this therapy. A panel of experts was convened to provide guidance regarding the appropriate use of negative-pressure wound therapy with instillation. A face-to-face meeting was held where the available evidence was discussed and individual clinical experience with this therapy was shared. Follow-up communication among the panelists continued until consensus was achieved. The final consensus recommendations were derived through more than 80 percent agreement among the panelists. Nine consensus statements were generated that address the appropriate use of negative-pressure wound therapy with instillation. The question of clinical effectiveness of this therapy was not directly addressed by the consensus panel. This document serves as preliminary guidelines until more robust evidence emerges that will support or modify these consensus recommendations.

  7. Perceived social pressure not to experience negative emotion is linked to selective attention for negative information.

    Science.gov (United States)

    Bastian, Brock; Pe, Madeline Lee; Kuppens, Peter

    2017-02-01

    Social norms and values may be important predictors of how people engage with and regulate their negative emotional experiences. Previous research has shown that social expectancies (the perceived social pressure not to feel negative emotion (NE)) exacerbate feelings of sadness. In the current research, we examined whether social expectancies may be linked to how people process emotional information. Using a modified classical flanker task involving emotional rather than non-emotional stimuli, we found that, for those who experienced low levels of NE, social expectancies were linked to the selective avoidance of negative emotional information. Those who experienced high levels of NE did not show a selective avoidance of negative emotional information. The findings suggest that, for people who experience many NEs, social expectancies may lead to discrepancies between how they think they ought to feel and the kind of emotional information they pay attention to.

  8. An anesthetic management of negative pressure pulmonary edema

    Directory of Open Access Journals (Sweden)

    Dipti Raj

    2016-01-01

    Full Text Available Negative pressure pulmonary edema (NPPE is one of the common complications of upper airway obstruction seen by anesthesiologist during either in induction or emergence sometimes both. Patients who have experienced NPPE are generally healthy without comorbidities. NPPE is a result of marked decrease in intrathoracic pressure caused by ventilator efforts against a closed glottis resulting in disruption of normal intravascular Starling mechanism, leading to transudation of intravascular protein, and fluids into the pulmonary interstitium. The onset of NPPE is usually rapid and without prompt recognition and intervention, the outcome can be fatal. This case report is of a 40-year-old female adult, who underwent right-sided percutaneous nephrolithotomy for stone in the right kidney otherwise uncomplicated surgical procedure.

  9. Negative pressure therapy for the treatment of complex wounds

    Directory of Open Access Journals (Sweden)

    RENAN VICTOR KÜMPEL SCHMIDT LIMA

    Full Text Available ABSTRACT The objective of this study is to evaluate the effectiveness of negative pressure therapy (NPT in the treatment of complex wounds, with emphasis on its mechanisms of action and main therapeutic indications. We searched the Pubmed / Medline database for articles published from 1997 to 2016, and selected the most relevant ones. The mechanisms of action of NPT involveboth physical effects, such as increased perfusion, control of edema and exudate, reduction of wound dimensions and bacterial clearance, and biological ones, such as the stimulation of granulation tissue formation, microdeformations and reduction of Inflammatory response. The main indications of NPT are complex wounds, such as pressure ulcers, traumatic wounds, operative wound dehiscences, burns, necrotizing wounds, venous ulcers, diabetic wounds, skin grafts, open abdomen, prevention of complications in closed incisions and in the association with instillation of solutions in infected wounds.

  10. Study on the hydrogen negative ion in low pressure discharges

    International Nuclear Information System (INIS)

    Bruneteau, A.M.

    1983-07-01

    A new use of negative hydrogen ions is the production of intense fast neutral atom beams useful in plasma heating in thermonuclear heating. That is one of the reasons that started this study. The density of negative hydrogen ions in diffusion, and multipole-type low pressure (10 -3 - 10-2 Torr) discharges is deduced from the various formation and destruction processes of the species present in these discharges. The H - ions are essentially produced by dissociative attachment to vibrationally excited molecules and destroyed by processes the relative importance of which is discussed as a function of the discharge parameters. The experimental study of the density of the H - ions, measured by photodetachment, as a function of these parameters, coroborates the theoretical model [fr

  11. Dynamic isolation technologies in negative pressure isolation wards

    CERN Document Server

    Xu, Zhonglin

    2017-01-01

    This book presents novel design principles and technologies for dynamic isolation based on experimental studies. These approaches have now become the local standard in Beijing and are currently being promoted for use nationwide. Further, the book provides details of measures and guidelines for the design process. Departing from the traditional understanding that isolation wards should be designed with high negative pressure, airtight doors and fresh air, it establishes the basis for designing biological clean rooms, including isolation wards, using a simple and convenient scientific approach. This book is intended for designers, engineers, researchers, hospital management staff and graduate students in heating ventilation air conditioning (HVAC), air cleaning technologies and related areas.

  12. Management of Pharyngocutaneous Fistula With Negative-Pressure Wound Therapy.

    Science.gov (United States)

    Teixeira, Sérgio; Costa, Joana; Bartosch, Isabel; Correia, Bernardo; Silva, Álvaro

    2017-06-01

    Pharyngocutaneous fistula is a common complication of laryngopharyngeal surgery and is associated with increased morbidity and mortality. Beyond the classical management, negative-pressure wound therapy (NPWT) can be an alternative and effective treatment. Two patients with pT3N0M0 squamous cell carcinoma of pyriform sinus were subjected to total laryngectomy and pharyngoesophageal reconstruction of a circular (patient 1) and an anterior wall defect (patient 2) with radial forearm free flap and pectoralis major muscle flap, respectively. Both developed a pharyngocutaneous fistula and NPWT was used.A significant decrease of the fistula aperture and exudate was observed after 22 and 21 days of NPWT in patients 1 and 2, respectively. After that standard wound care was instituted and closure of the fistulae was accomplished in 5 and 7 days, respectively. Negative-pressure wound therapy can be an effective treatment for pharyngocutaneous fistula closure, either in the setting of fistulae that persist besides multiple surgical revisions using muscle flaps or as a first-line therapy when fistulae develops.

  13. Solvation pressure as real pressure: I. Ethanol and starch under negative pressure

    CERN Document Server

    Uden, N W A V; Faux, D A; Tanczos, A C; Howlin, B; Dunstan, D J

    2003-01-01

    The reality of the solvation pressure generated by the cohesive energy density of liquids is demonstrated by three methods. Firstly, the Raman spectrum of ethanol as a function of cohesive energy density (solvation pressure) in ethanol-water and ethanol-chloroform mixtures is compared with the Raman spectrum of pure ethanol under external hydrostatic pressure and the solvation pressure and hydrostatic pressure are found to be equivalent for some transitions. Secondly, the bond lengths of ethanol are calculated by molecular dynamics modelling for liquid ethanol under pressure and for ethanol vapour. The difference in bond lengths between vapour and liquid are found to be equivalent to the solvation pressure for the C-H sub 3 , C-H sub 2 and O-H bond lengths, with discrepancies for the C-C and C-O bond lengths. Thirdly, the pressure-induced gelation of potato starch is measured in pure water and in mixtures of water and ethanol. The phase transition pressure varies in accordance with the change in solvation pre...

  14. Human treadmill walking needs attention

    Directory of Open Access Journals (Sweden)

    Daniel Olivier

    2006-08-01

    Full Text Available Abstract Background The aim of the study was to assess the attentional requirements of steady state treadmill walking in human subjects using a dual task paradigm. The extent of decrement of a secondary (cognitive RT task provides a measure of the attentional resources required to maintain performance of the primary (locomotor task. Varying the level of difficulty of the reaction time (RT task is used to verify the priority of allocation of attentional resources. Methods 11 healthy adult subjects were required to walk while simultaneously performing a RT task. Participants were instructed to bite a pressure transducer placed in the mouth as quickly as possible in response to an unpredictable electrical stimulation applied on the back of the neck. Each subject was tested under five different experimental conditions: simple RT task alone and while walking, recognition RT task alone and while walking, walking alone. A foot switch system composed of a pressure sensitive sensor was placed under the heel and forefoot of each foot to determine the gait cycle duration. Results Gait cycle duration was unchanged (p > 0.05 by the addition of the RT task. Regardless of the level of difficulty of the RT task, the RTs were longer during treadmill walking than in sitting conditions (p 0.05 was found between the attentional demand of the walking task and the decrement of performance found in the RT task under varying levels of difficulty. This finding suggests that the healthy subjects prioritized the control of walking at the expense of cognitive performance. Conclusion We conclude that treadmill walking in young adults is not a purely automatic task. The methodology and outcome measures used in this study provide an assessment of the attentional resources required by walking on the treadmill at a steady state.

  15. Effect of aerobic capacity on Lower Body Negative Pressure (LBNP) tolerance in females

    Science.gov (United States)

    Moore, Alan D., Jr.; Fortney, Suzanne M.; Siconolfi, Steven F.

    1993-01-01

    This investigation determined whether a relationship exists in females between: (1) aerobic capacity and Lower Body Negative Pressure (LBNP); and (2) aerobic capacity and change in LBNP tolerance induced by bed rest. Nine females, age 27-47 (34.6 plus or minus 6.0 (Mean plus or minus SD)), completed a treadmill-graded exercise test to establish aerobic capacity. A presyncopal-limited LBNP test was performed prior to and after 13 days of bed rest at a 6 deg head-down tilt. LBNP tolerance was quantified as: (1) the absolute level of negative pressure (NP) tolerated for greater than or equal to 60 sec; and (2) Luft's Cumulative Stress Index (CSI). Aerobic capacity was 33.3 plus or minus 5.0 mL/kg/min and ranged from 25.7 to 38.7. Bed rest was associated with a decrease in NP tolerance (-9.04 1.6 kPa(-67.8 plus or minus 12.0 mmHg) versus -7.7 1.1 kPa(-57.8 plus or minus 8.33 mmHg); p = 0.028) and in CSI (99.4 27.4 kPa min(745.7 plus or minus 205.4 mmHg min) versus 77.0 16.9 kPa min (577.3 plus or minus mmHg min); p = 0.008). The correlation between aerobic capacity and absolute NP or CSI pre-bed rest did not differ significantly from zero (r = -0.56, p = 0.11 for NP; and r = -0.52, p = 0.16 for CSI). Also, no significant correlation was observed between aerobic and pre- to post-rest change for absolute NP tolerance (r = -0.35, p = 0.35) or CSI (r = -0.32, p = 0.40). Therefore, a significant relationship does not exist between aerobic capacity and orthostatic function or change in orthostatic function induced by bed rest.

  16. Physical fitness and cardiovascular response to lower body negative pressure

    Science.gov (United States)

    Raven, P. B.; Rohm-Young, D.; Blomqvist, C. G.

    1984-01-01

    Klein et al. (1977) have questioned the concept of endurance training as an appropriate means of preparing for prolonged space flights. Their opinion was mainly based on reports of endurance athletes who had a decreased tolerance to orthostatic or gravitational stress induced by lower body negative pressure (LBNP), upright tilt, or whole body water immersion. The present investigation had the objective to determine if the hemodynamic response to LBNP is different between a high and average fit group of subjects. In addition, the discrete aspect of cardiovascular function which had been altered by chronic training was to be identified. On the basis of the results of experiments conducted with 14 young male volunteers, it is concluded that the reflex response to central hypovolemia is altered by endurance exercise training.

  17. Homogeneous nucleation in liquid nitrogen at negative pressures

    Energy Technology Data Exchange (ETDEWEB)

    Baidakov, V. G., E-mail: baidakov@itp.uran.ru; Vinogradov, V. E.; Pavlov, P. A. [Russian Academy of Sciences, Institute of Thermal Physics, Ural Branch (Russian Federation)

    2016-10-15

    The kinetics of spontaneous cavitation in liquid nitrogen at positive and negative pressures has been studied in a tension wave formed by a compression pulse reflected from the liquid–vapor interface on a thin platinum wire heated by a current pulse. The limiting tensile stresses (Δp = p{sub s}–p, where p{sub s} is the saturation pressure), the corresponding bubble nucleation frequencies J (10{sup 20}–10{sup 22} s{sup –1} m{sup –3}), and temperature induced nucleation frequency growth rate G{sub T} = dlnJ/dT have been experimentally determined. At T = 90 K, the limiting tensile stress was Δp = 8.3 MPa, which was 4.9 MPa lower than the value corresponding to the boundary of thermodynamic stability of the liquid phase (spinodal). The measurement results were compared to classical (homogeneous) nucleation theory (CNT) with and without neglect of the dependence of the surface tension of critical bubbles on their dimensions. In the latter case, the properties of new phase nuclei were described in terms of the Van der Waals theory of capillarity. The experimental data agree well with the CNT theory when it takes into account the “size effect.”.

  18. Incisional Negative Pressure Wound Therapy in High Risk Patients Undergoing Panniculectomy: A Prospective Randomized Controlled Trial

    Science.gov (United States)

    2018-01-16

    Complications Wounds; Negative Pressure Wound Therapy; Wound Healing Delayed; Incisional; Panniculectomy; Incisional Negative Pressure Wound Therapy; Incisional Vac; Wound Vac; Obese; Renal Failure; Kidney Transplant; Complications; Wound Healing Complication

  19. Paediatric treadmill friction injuries.

    Science.gov (United States)

    Jeremijenko, Luke; Mott, Jonathan; Wallis, Belinda; Kimble, Roy

    2009-05-01

    The aim of this study was to report on the severity and incidence of children injured by treadmills and to promote the implementation of safety standards. This retrospective review of children with treadmill friction injuries was conducted in a single tertiary-level burns centre in Australia between January 1997 and June 2007. The study revealed 37 children who sustained paediatric treadmill friction injuries. This was a presentation of 1% of all burns. Thirty-three (90%) of the injuries occurred in the last 3.5 years (January 2004 to June 2007). The modal age was 3.2 years. Thirty-three (90%) injuries were either full thickness or deep partial friction burns. Eleven (30%) required split thickness skin grafts. Of those who became entrapped, 100% required skin grafting. This study found that paediatric treadmill friction injuries are severe and increasing in incidence. Australian standards should be developed, implemented and mandated to reduce this preventable and severe injury.

  20. Negative pressure wound therapy for partial-thickness burns.

    Science.gov (United States)

    Dumville, Jo C; Munson, Christopher; Christie, Janice

    2014-12-15

    A burn wound is a complex and evolving injury, with both local and systemic consequences. Burn treatments include a variety of dressings, as well as newer strategies, such as negative pressure wound therapy (NPWT), which, by means of a suction force that drains excess fluids from the burn, tries to promote the wound healing process and minimise progression of the burn wound. To assess the effectiveness of NPWT for people with partial-thickness burns. We searched the Cochrane Wounds Group Specialised Register (searched 04 September 2014); The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2014, Issue 8). All randomised controlled trials (RCTs) and controlled clinical trials (CCTs) that evaluated the safety and effectiveness of NPWT for partial-thickness burns. Two review authors used standardised forms, and extracted the data independently. We assessed each trial for risk of bias, and resolved differences by discussion. One RCT, that was an interim report, satisfied the inclusion criteria. We undertook a narrative synthesis of results, as the absence of data and poor reporting precluded us from carrying out any formal statistical analysis. The trial was at high risk of bias. There was not enough evidence available to permit any conclusions to be drawn regarding the use of NPWT for treatment of partial-thickness burn wounds.

  1. Negative pressure wound therapy in patients with diabetic foot.

    Science.gov (United States)

    Ulusal, Ali Engin; Sahin, M Sükrü; Ulusal, Betül; Cakmak, Gökhan; Tuncay, Cengiz

    2011-01-01

    In this study our aim was to compare the results of standard dressing treatment to negative pressure wound therapy (NPWT) performed with a vacuum-assisted closure (VAC) device in patients with diabetic foot ulcers. We assessed the results of 35 patients treated for diabetic foot ulcer between 2006 and 2008. Of these cases, 20 (4 women and 16 men; mean age: 66 years; range: 52-90 years) were treated with standard wet dressings and 16 feet in 15 patients (10 men, 5 women; mean age: 58.9 years; range: 42-83 years) with VAC therapy. The success of treatment was evaluated in terms of hospitalization length and rate of limb salvation. The average hospitalization period with VAC treatment was 32 days compared to 59 days with standard dressing treatment. All patients treated with standard dressings eventually had to undergo amputation. However, the amputation rate was 37% in the VAC treated group and 88% of patients had a functional extremity at the end of treatment. VAC therapy, together with debridement and appropriate antibiotic therapy, enables a higher rate of limb salvage, especially in Wagner Grade 3 and Grade 4 ulcers.

  2. [Clinical analysis of 4 children with negative pressure pulmonary edema].

    Science.gov (United States)

    Chen, Jiehua; Wang, Shu; Ma, Hongling; Wang, Wenjian; Fu, Dan; Huang, Wenxian; Deng, Jikui; Tang, Huiying; He, Yanxia; Zheng, Yuejie

    2014-02-01

    To analyze the clinical characteristics of negative pressure pulmonary edema (NPPE). A retrospective investigation of the clinical manifestation, imageology, clinical course and outcome of 4 children with NPPE seen between June 2012 and July 2013 in a children's hospital. The causation of the airway obstruction was also explored. All the 4 cases were boys, the range of age was 40 days to 9 years. They had no history of respiratory and circulatory system disease. In 3 cases the disease had a sudden onset after the obstruction of airway, and in one the onset occurred 1.5 hours after removing the airway foreign body. All these cases presented with tachypnea, dyspnea, and cyanosis, none had fever. Three cases had coarse rales. Chest radiography was performed in 3 cases and CT scan was performed in 1 case, in all of them both lungs displayed diffuse ground-glass-like change and patchy consolidative infiltrates. Three cases were admitted to the ICU, duration of mechanical ventilation was less than 24 hours in 2 cases and 39 hours in one. Oxygen was given by mask to the remaining one in emergency department, whose symptoms were obviously improved in 10 hours. None was treated with diuretics, glucocorticoids or inotropic agents. Chest radiographs were taken within 24 hours of treatment in 2 cases and 24-48 hours in the other 2; almost all the pulmonary infiltrates were resolved. All the 4 cases were cured. The causes of airway obstruction were airway foreign bodies in two cases, laryngospasm in one and laryngomalacia in the other. NPPE is a life-threatening emergency, which is manifested by rapid onset of respiratory distress rapidly (usually in several minutes, but might be hours later) after relief of the airway obstruction, with findings of pulmonary edema in chest radiograph. The symptoms resolve rapidly by oxygen therapy timely with or without mechanical ventilation. In children with airway obstruction, NPPE should be considered.

  3. Contrastive Analysis and Research on Negative Pressure Beam Tube System and Positive Pressure Beam Tube System for Mine Use

    Science.gov (United States)

    Wang, Xinyi; Shen, Jialong; Liu, Xinbo

    2018-01-01

    Against the technical defects of universally applicable beam tube monitoring system at present, such as air suction in the beam tube, line clogging, long sampling time, etc., the paper analyzes the current situation of the spontaneous combustion fire disaster forecast of mine in our country and these defects one by one. On this basis, the paper proposes a research thought that improving the positive pressure beam tube so as to substitute the negative pressure beam tube. Then, the paper introduces the beam tube monitoring system based on positive pressure technology through theoretical analysis and experiment. In the comparison with negative pressure beam tube, the paper concludes the advantage of the new system and draws the conclusion that the positive pressure beam tube is superior to the negative pressure beam tube system both in test result and test time. At last, the paper proposes prospect of the beam tube monitoring system based on positive pressure technology.

  4. Role of Negative Pressure Wound Therapy in Healing of Diabetic ...

    African Journals Online (AJOL)

    Journal of Surgical Technique and Case Report | Jan-Jun 2011 | Vol-3 | Issue-1. 10. Role of Negative ... case of any difficulty faced in the application of VAC dressings. BLEEDING ISSUE ... show exposed bone, tendon, joint capsule or fascia.

  5. The therapeutic effect of negative pressure in treating femoral head necrosis in rabbits.

    Science.gov (United States)

    Zhang, Yin-gang; Wang, Xuezhi; Yang, Zhi; Zhang, Hong; Liu, Miao; Qiu, Yushen; Guo, Xiong

    2013-01-01

    Because negative pressure can stimulate vascular proliferation, improve blood circulation and promote osteogenic differentiation of bone marrow stromal cells, we investigated the therapeutic effect of negative pressure on femoral head necrosis (FHN) in a rabbit model. Animals were divided into four groups (n = 60/group): [1] model control, [2] core decompression, [3] negative pressure and [4] normal control groups. Histological investigation revealed that at 4 and 8 weeks postoperatively, improvements were observed in trabecular bone shape, empty lacunae and numbers of bone marrow hematopoietic cells and fat cells in the negative pressure group compared to the core decompression group. At week 8, there were no significant differences between the negative pressure and normal control groups. Immunohistochemistry staining revealed higher expression of vascular endothelial growth factor (VEGF) and bone morphogenetic protein-2 (BMP-2) in the femoral heads in the negative pressure group compared with the core decompression group. Transmission electron microscopy revealed that cell organelles were further developed in the negative pressure group compared with the core decompression group. Microvascular ink staining revealed an increased number of bone marrow ink-stained blood vessels, a thicker vascular lumen and increased microvascular density in the negative pressure group relative to the core decompression group. Real-time polymerase chain reaction revealed that expression levels of both VEGF and BMP-2 were higher in the negative pressure group compared with the core decompression group. In summary, negative pressure has a therapeutic effect on FHN. This effect is superior to core decompression, indicating that negative pressure is a potentially valuable method for treating early FHN.

  6. Dynamic Leg Exercise Improves Tolerance to Lower Body Negative Pressure

    Science.gov (United States)

    Watenpaugh, D. E.; Ballard, R. E.; Stout, M. S.; Murthy, G.; Whalen, R. T.; Hargens, A. R.

    1994-01-01

    These results clearly demonstrate that dynamic leg exercise against the footward force produced by LBNP substantially improves tolerance to LBNP, and that even cyclic ankle flexion without load bearing also increases tolerance. This exercise-induced increase of tolerance was actually an underestimate, because subjects who completed the tolerance test while exercising could have continued for longer periods. Exercise probably increases LBNP tolerance by multiple mechanisms. Tolerance was increased in part by skeletal muscle pumping venous blood from the legs. Rosenhamer and Linnarsson and Rosenhamer also deduced this for subjects cycling during centrifugation, although no measurements of leg volume were made in those studies: they found that male subjects cycling at 98 W could endure 3 Gz centrifugation longer than when they remained relaxed during centrifugation. Skeletal muscle pumping helps maintain cardiac filling pressure by opposing gravity-, centrifugation-, or LBNP-induced accumulation of blood and extravascular fluid in the legs.

  7. Mechanisms of lower body negative pressure-induced syncope

    Science.gov (United States)

    Davrath, Linda Ruble

    Although extensively investigated, the mechanisms of post-spaceflight orthostatic intolerance have not been elucidated. The working hypothesis was that a markedly reduced left ventricular end-systolic volume (LVESV) would be achieved during progressive, presyncopal-limited LBNP and would cause bradycardia and a fall in blood pressure, thus triggering syncope. Eight healthy men, age 25.1 ± 1.3 years, volunteered for the study. Subjects were exposed to graded levels of LBNP on two separate occasions. Changes in left ventricular end-diastolic volume and LVESV were measured, using two-dimensional echocardiography, at each stage of LBNP from rest to presyncope. Plasma venous blood samples were withdrawn at the end of each stage of the LBNP protocol for the measurement of plasma venous catecholamines and plasma renin activity (PRA). Catecholamines were analyzed by HPLC with electro-chemical detection, and PRA was determined by radioimmunoassay. All subjects reached presyncope during the LBNP. LVESV decreased by 28% at presyncope with no evidence of ventricular cavity obliteration. Norepinephrine (NE) increased by 44% from rest to presyncope, but no epinephrine surge was detected (35% increase from rest to presyncope). These data indicate that it is possible to initiate syncope with only a 28% decrease in LVESV, and that sympatho-inhibition and bradycardia are not required elements for syncope to occur. To investigate the effect of moderate sodium restriction on cardiovascular hemodynamics and orthostatic tolerance, presyncopal LBNP testing was performed. Urinary sodium excretion was significantly higher on the normal-sodium diet when compared with the sodium-restricted diet, but urinary potassium was not different. Cumulative stress index (655 ± 460 on normal-sodium diet vs. 639 ± 388 on sodium-restricted diet) scores were not different. Cardiac volumes, blood pressure and total peripheral resistance were not different at any stage of the LBNP between the diets, nor

  8. Negative-Pressure Hydrocephalus: A Case Report on Successful Treatment Under Intracranial Pressure Monitoring with Bilateral Ventriculoperitoneal Shunts.

    Science.gov (United States)

    Pandey, Sajan; Jin, Yi; Gao, Liang; Zhou, Cheng Cheng; Cui, Da Ming

    2017-03-01

    Negative-pressure hydrocephalus (NegPH), a very rare condition of unknown etiology and optimal treatment, usually presents postneurosurgery with clinical and imaging features of hydrocephalus, but with negative cerebrospinal fluid pressure. We describe a NegPH case of -3 mm Hg intracranial pressure that was successfully treated to achieve 5 mm Hg under continuous intracranial pressure monitoring with horizontal positioning, head down and legs elevated to 10°-15°, neck wrapping for controlled venous drainage, chest and abdomen bandages, infusion of 5% dextrose fluid to lower plasma osmolarity (Na + , 130-135 mmol/L), daily cerebrospinal fluid drainage >200 mL, and arterial blood gas partial pressure of carbon dioxide >40 mm Hg. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Treatment Experience of Continuous Negative Pressure Drainage in the Acute Anterior Mediastinal Infection of Oropharyngeal Origined

    Directory of Open Access Journals (Sweden)

    Anping CHEN

    2018-04-01

    Full Text Available Background and objective Mediastinal infection is a serious infection of mediastinal connective tissue, with more complications and higher mortality. Application of broad-spectrum antibiotics and nutritional support, early sufficient drainage is the key to successful treatment. In the mode of drainage, this paper discusses the application of continuous negative pressure drainage technique to treat acute anterior mediastinal infection of severe mouth pharynx source, and the good results are summarized and shared. Methods In January to December in 2017, a total of 17 cases treated acute mediastinal infection is derived from the throat, has formed a mediastinal abscess, surgery adopts retrosternal counterpart negative pressure drainage way, namely the sternum nest and free sternum xiphoid process under the incision on the first mediastinal clearance, make breakthrough and placed drainage device, suture closed wound, continuous negative pressure drainage, negative pressure using 3 cm-5 cm water column. Results Among the 17 patients, 14 patients were relieved by continuous negative pressure drainage, and then the drainage tube was removed. In 2 cases, the infection broke into the right thoracic cavity, and the closed drainage caused the negative pressure to disappear, and the negative pressure drainage was replaced by the conventional drainage, and the drainage tube was removed after the drainage tube was clear. One patient had formed a mediastinal abscess incision drainage time later, complicated with septic shock and sepsis, resulting in the death of multiple organ failure. Conclusion The traditional treatment of severe acute mediastinal infection is sternal incision and drainage. Continuous negative pressure drainage adequate drainage of mediastinal can relieve patients' pain, effusion, and avoid the dressing out repeatedly. It is an effective method. However, there are limitations in this method, which need to be further optimized.

  10. Negative Pressure Pulmonary Edema after Reversing Rocuronium-Induced Neuromuscular Blockade by Sugammadex

    Directory of Open Access Journals (Sweden)

    Manzo Suzuki

    2014-01-01

    Full Text Available Negative pressure pulmonary edema (NPPE is a rare complication that accompanies general anesthesia, especially after extubation. We experienced a case of negative pressure pulmonary edema after tracheal extubation following reversal of rocuronium-induced neuromuscular blockade by sugammadex. In this case, the contribution of residual muscular block on the upper airway muscle as well as large inspiratory forces created by the respiratory muscle which has a low response to muscle relaxants, is suspected as the cause.

  11. Empirical Formulas for Calculation of Negative Pressure Difference in Vacuum Pipelines

    Directory of Open Access Journals (Sweden)

    Marek Kalenik

    2015-10-01

    Full Text Available The paper presents the analysis of results of empirical investigations of a negative pressure difference in vacuum pipelines with internal diameters of 57, 81, 102 mm. The investigations were performed in an experimental installation of a vacuum sewage system, built in a laboratory hall on a scale of 1:1. The paper contains a review of the literature concerning two-phase flows (liquid-gas in horizontal, vertical and diagonal pipelines. It presents the construction and working principles of the experimental installation of vacuum sewage system in steady and unsteady conditions during a two-phase flow of water and air. It also presents a methodology for determination of formula for calculation of a negative pressure difference in vacuum pipelines. The results obtained from the measurements of the negative pressure difference Δpvr in the vacuum pipelines were analyzed and compared with the results of calculations of the negative pressure difference Δpvr, obtained from the determined formula. The values of the negative pressure difference Δpvr calculated for the vacuum pipelines with internal diameters of 57, 81, and 102 mm with the use of Formula (19 coincide with the values of Δpvr measured in the experimental installation of a vacuum sewage system. The dependence of the negative pressure difference Δpvr along the length of the vacuum pipelines on the set negative pressure in the vacuum container pvzp is linear. The smaller the vacuum pipeline diameter, the greater the negative pressure difference Δpvr is along its length.

  12. Management of High-Voltage Burns of the Hand and Wrist with Negative Pressure Dressing

    Directory of Open Access Journals (Sweden)

    Nazım Gümüş

    2017-12-01

    Full Text Available Objective: Negative pressure dressing stimulates wound healing by promoting cellular proliferation and regeneration. It also removes interstitial edema and increases local blood flow, resulting in rapid growth of the granulation tissue. We used the dressing method in deep hand and wrist burns caused by high-voltage electrical current, which leads to progressive tissue necrosis, elevated compartment pressure, and deep tissue edema, to reveal if subatmospheric pressure could limit the zone of injury or ongoing tissue necrosis after electrical burn. Material and Methods: Six hands of five patients, who came in contact with high-voltage electrical wire carrying more than 1000 volts, are presented in this study. Hands and wrists were seriously injured and contracted. After the initial treatment involving fluid resuscitation, fasciotomy, carpal tunnel release, and debridement, a negative pressure dressing was applied to the wounds of hand, wrist, and forearm with 125 mm Hg continuous pressure, and maintained for 20 days. Results: When negative pressure dressing was stopped on the 20th day, significant granulation tissue developed over the hand and forearm wounds. However, wrist wounds needed more debridement and repeated dressings because of the presence of necrosis. Edema of the hands subsided significantly during the use of negative pressure dressing. Time to closure for hand and forearm wounds decreased considerably. Moreover, in one wrist, spontaneous closure was achieved at about one month. All hands except one treated with negative pressure dressing could be saved from amputation; however, significant tissue loss developed, needing complex reconstruction procedures. One hand was amputated because of the permanent loss of blood perfusion. Conclusion: The management of high-voltage burns of hand and wrist with subatmospheric pressure appears to be capable of reducing hand edema and accelerating closure of the wounds. It seems that negative

  13. The effects of superimposed tilt and lower body negative pressure on anterior and posterior cerebral circulations

    OpenAIRE

    Tymko, Michael M.; Rickards, Caroline A.; Skow, Rachel J.; Ingram?Cotton, Nathan C.; Howatt, Michael K.; Day, Trevor A.

    2016-01-01

    Abstract Steady?state tilt has no effect on cerebrovascular reactivity to increases in the partial pressure of end?tidal carbon dioxide (PETCO 2). However, the anterior and posterior cerebral circulations may respond differently to a variety of stimuli that alter central blood volume, including lower body negative pressure (LBNP). Little is known about the superimposed effects of head?up tilt (HUT; decreased central blood volume and intracranial pressure) and head?down tilt (HDT; increased ce...

  14. A successful capital treadmill

    International Nuclear Information System (INIS)

    Bohun, D.A.

    1995-01-01

    A summary of the operating economics of the Winter Cummings Sand Pool, a horizontal well development project with a sustained rate of development, was presented. A total of 58 horizontal wells have been drilled over a time span of seven years. The production performance of the first pilot wells indicated that development of the pool by horizontal wells could be economically viable. Since its inception the Winter field development was considered to have become a capital treadmill with an incremental rate of return on the incremental investment of 240 percent (a 24 million dollar net operating cash flow for a 10 million dollar investment). Current development status and production forecasts were also discussed. 21 figs

  15. Application of vacuum-assisted closure in seawater-immersed wound treatment under different negative pressures.

    Science.gov (United States)

    Cao, L; Peng, M M; Sun, J J; Yu, X C; Shi, B

    2015-06-11

    The therapeutic effect of vacuum-assisted closure (VAC) has been confirmed in many types of complex wounds, but there are few relevant reports regarding seawater-immersed wounds. The aim of this study was to determine the effect of VAC on seawater-immersed wound healing under different negative pressures and explore the optimal negative pressure value. Four purebred miniature pigs were used as the experimental animal models. Four acute, symmetrical wounds were made on each side of the spine and designated as the experimental group (wounds with 2 h of seawater immersion) and the control group (wounds without seawater immersion). Wounds were divided into a conventional dressing group and 3 further groups with different VAC therapies (negative pressure at either 120, 180, or 240 mmHg). The extent of wound healing, and speed of granulation growth and re-epithelialization were measured. Bacterial flora distribution in the wounds was observed, and fibronectin levels in the exudate of the wounds were tested. Results showed that seawater immersion aggravated wound injury and that VAC therapy with 180 mmHg negative pressure induced the fastest epidermis migration, obvious edema elimination, significant capillary proliferation, and the highest level of fibronectin, and that in wounds, the proportion of Gram-negative bacteria tended to decrease and that of Gram-positive bacteria tended to increase. Our results show that VAC promotes seawater-immersed wound healing and that 180 mmHg negative pressure may be optimal for wound healing.

  16. Measurement of negative ion mobilities in O2 and O3 mixtures at atmospheric pressure

    International Nuclear Information System (INIS)

    Itoh, H.; Norimoto, K.; Hayashi, T.

    1998-01-01

    Mobility measurements of negative molecular oxygen ions in pure oxygen and in an oxygen-ozone mixture are reported. A cascaded gap consisting of an ion drift gap and an ion detection gap was used in the experiment. The ion detection gap was formed by a positive point and a grounded plane electrode was operated at atmospheric pressure. The zero field mobility of negative molecular oxygen ions was determined to be 2.07+-0.02 cm 2 /V.s. A somewhat higher value of oxygen mobility was found at higher electric field/pressure ratios; this is presumed to be due to negative ozone ions. When changing the electric field/pressure ratio the mobility of negative oxygen ions in oxygen-ozone mixtures becomes smaller than that in pure oxygen; this is probably due to the cumulative effect of other particles produced by silent discharges. (J.U.)

  17. The paradox of negative pressure wound therapy--in vitro studies.

    Science.gov (United States)

    Kairinos, Nicolas; Solomons, Michael; Hudson, Donald A

    2010-01-01

    Negative-pressure wound therapy (NPWT) has revolutionised wound care. Yet, it is still not understood how hypobaric tissue pressure accelerates wound healing. There is very little reported on the relevant physics of any substance subjected to suction in this manner. The common assumption is that applying suction to a substance is likely to result in a reduction of pressure in that substance. Although more than 250 research articles have been published on NPWT, there are little data verifying whether suction increases or decreases the pressure of the substance it is applied to. Clarifying this basic question of physics is the first step in understanding the mechanism of action of these dressings. In this study, pressure changes were recorded in soft plasticene and processed meat, using an intracranial tissue pressure microsensor. Circumferential, non-circumferential and cavity NPWT dressings were applied, and pressure changes within the underlying substance were recorded at different suction pressures. Pressures were also measured at 1cm, 2 cm and 3 cm from the NPWT placed in a cavity. In all three types of NPWT dressings, the underlying substance pressure was increased (hyperbaric) as suction pressure increased. Although there was a substantial pressure increase at 1cm, the rise in pressure at the 2-cm and 3-cm intervals was minimal. Substance pressure beneath all types of NPWT dressing is hyperbaric in inanimate substances. Higher suction pressures generate greater substance pressures; however, the increased pressure rapidly dissipates as the distance from the dressing is increased. The findings of this study on inanimate objects suggest that we may need to review our current perception of the physics underlying NPWT dressings. Further research of this type on living tissues is warranted. Copyright (c) 2009 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  18. Asymmetric Fuzzy Control of a Positive and Negative Pneumatic Pressure Servo System

    Science.gov (United States)

    Yang, Gang; Du, Jing-Min; Fu, Xiao-Yun; Li, Bao-Ren

    2017-11-01

    The pneumatic pressure control systems have been used in some fields. However, the researches on pneumatic pressure control mainly focus on constant pressure regulation. Poor dynamic characteristics and strong nonlinearity of such systems limit its application in the field of pressure tracking control. In order to meet the demand of generating dynamic pressure signal in the application of the hardware-in-the-loop simulation of aerospace engineering, a positive and negative pneumatic pressure servo system is provided to implement dynamic adjustment of sealed chamber pressure. A mathematical model is established with simulation and experiment being implemented afterwards to discuss the characteristics of the system, which shows serious asymmetry in the process of charging and discharging. Based on the analysis of the system dynamics, a fuzzy proportional integral derivative (PID) controller with asymmetric fuzzy compensator is proposed. Different from conventional adjusting mechanisms employing the error and change in error of the controlled variable as input parameters, the current chamber pressure and charging or discharging state are chosen as inputs of the compensator, which improves adaptability. To verify the effectiveness and performance of the proposed controller, the comparison experiments tracking sinusoidal and square wave commands are conducted. Experimental results show that the proposed controller can obtain better dynamic performance and relatively consistent control performance across the scope of work (2-140 kPa). The research proposes a fuzzy control method to overcome asymmetry and enhance adaptability for the positive and negative pneumatic pressure servo system.

  19. A pressure-amplifying framework material with negative gas adsorption transitions.

    Science.gov (United States)

    Krause, Simon; Bon, Volodymyr; Senkovska, Irena; Stoeck, Ulrich; Wallacher, Dirk; Többens, Daniel M; Zander, Stefan; Pillai, Renjith S; Maurin, Guillaume; Coudert, François-Xavier; Kaskel, Stefan

    2016-04-21

    Adsorption-based phenomena are important in gas separations, such as the treatment of greenhouse-gas and toxic-gas pollutants, and in water-adsorption-based heat pumps for solar cooling systems. The ability to tune the pore size, shape and functionality of crystalline porous coordination polymers--or metal-organic frameworks (MOFs)--has made them attractive materials for such adsorption-based applications. The flexibility and guest-molecule-dependent response of MOFs give rise to unexpected and often desirable adsorption phenomena. Common to all isothermal gas adsorption phenomena, however, is increased gas uptake with increased pressure. Here we report adsorption transitions in the isotherms of a MOF (DUT-49) that exhibits a negative gas adsorption; that is, spontaneous desorption of gas (methane and n-butane) occurs during pressure increase in a defined temperature and pressure range. A combination of in situ powder X-ray diffraction, gas adsorption experiments and simulations shows that this adsorption behaviour is controlled by a sudden hysteretic structural deformation and pore contraction of the MOF, which releases guest molecules. These findings may enable technologies using frameworks capable of negative gas adsorption for pressure amplification in micro- and macroscopic system engineering. Negative gas adsorption extends the series of counterintuitive phenomena such as negative thermal expansion and negative refractive indices and may be interpreted as an adsorptive analogue of force-amplifying negative compressibility transitions proposed for metamaterials.

  20. Early use of negative pressure therapy in combination with silver dressings in a difficult breast abscess.

    Science.gov (United States)

    Richards, Alastair J; Hagelstein, Sue M; Patel, Girish K; Ivins, Nicola M; Sweetland, Helen M; Harding, Keith G

    2011-12-01

    Combining silver-based dressings with negative pressure therapy after radical excision of chronically infected breast disease is a novel application of two technologies. One patient with complex, chronic, infected breast disease underwent radical excision of the affected area and was treated early with a combination of silver-based dressings and topical negative pressure therapy. The wound was then assessed sequentially using clinical measurements of wound area and depth, pain severity scores and level of exudation. It is possible to combine accepted techniques with modern dressing technologies that result in a positive outcome. In this case, the combination of a silver-based dressing with negative pressure therapy following radical excision proved safe and was well tolerated by the patient. Full epithelisation of the wound was achieved and there was no recurrence of the infection for the duration of the treatment. © 2011 The Authors. © 2011 Blackwell Publishing Ltd and Medicalhelplines.com Inc.

  1. Modular Control of Treadmill vs Overground Running

    Science.gov (United States)

    Farina, Dario; Kersting, Uwe Gustav

    2016-01-01

    Motorized treadmills have been widely used in locomotion studies, although a debate remains concerning the extrapolation of results obtained from treadmill experiments to overground locomotion. Slight differences between treadmill (TRD) and overground running (OVG) kinematics and muscle activity have previously been reported. However, little is known about differences in the modular control of muscle activation in these two conditions. Therefore, we aimed at investigating differences between motor modules extracted from TRD and OVG by factorization of multi-muscle electromyographic (EMG) signals. Twelve healthy men ran on a treadmill and overground at their preferred speed while we recorded tibial acceleration and surface EMG from 11 ipsilateral lower limb muscles. We extracted motor modules representing relative weightings of synergistic muscle activations by non-negative matrix factorization from 20 consecutive gait cycles. Four motor modules were sufficient to accurately reconstruct the EMG signals in both TRD and OVG (average reconstruction quality = 92±3%). Furthermore, a good reconstruction quality (80±7%) was obtained also when muscle weightings of one condition (either OVG or TRD) were used to reconstruct the EMG data from the other condition. The peak amplitudes of activation signals showed a similar timing (pattern) across conditions. The magnitude of peak activation for the module related to initial contact was significantly greater for OVG, whereas peak activation for modules related to leg swing and preparation to landing were greater for TRD. We conclude that TRD and OVG share similar muscle weightings throughout motion. In addition, modular control for TRD and OVG is achieved with minimal temporal adjustments, which were dependent on the phase of the running cycle. PMID:27064978

  2. Negative pressure wound therapy and external fixation device: a simple way to seal the dressing.

    Science.gov (United States)

    Bulla, Antonio; Farace, Francesco; Uzel, André-Pierre; Casoli, Vincent

    2014-07-01

    Negative pressure therapy is widely applied to treat lower limb trauma. However, sealing a negative pressure dressing in the presence of an external fixation device may be difficult and time consuming. Therefore, screws, pins, wires, etc, may preclude the vacuum, preventing the plastic drape to perfectly adhere to the foam. To maintain the vacuum, we tried to prevent air leaking around the screws putting bone wax at the junction between the pins and the plastic drape. This solution, in our hands, avoids air leakage and helps maintain vacuum in a fast and inexpensive way.

  3. Negative Pressure Pulmonary Edema Following use of Laryngeal Mask Airway (LMA

    Directory of Open Access Journals (Sweden)

    Yesim Bayraktar

    2013-06-01

    Full Text Available Negative pressure pulmonary edema (NPPE following upper airway obstruction is a non-cardiogenic pulmonary edema. The first cause in the etiology of NPPE is developed laryngospasm after intubation or extubation, while the other causes are epiglotitis, croup, hiccups, foreign body aspiration, pharyngeal hematoma and oropharyngeal tumors.The Late diagnosis and treatment causes high morbidity and mortality. The protection of the airway and maintainance of arterial oxygenation will be life saving.In this article we aimed to report  a case of negative pressure pulmonary edema, resolved succesfully after treatment, following use of laryngeal mask airway (LMA.

  4. Relaxation effects in ionic mobility and cluster formation: negative ions in SF6 at high pressures

    International Nuclear Information System (INIS)

    Juarez, A M; De Urquijo, J; Hinojosa, G; Hernandez-Avila, J L; Basurto, E

    2010-01-01

    The relaxation effects of the ionic mobility and the formation of negative-ion clusters in SF 6 are studied in this work. For this purpose, we have measured the mobility of negative ions in SF 6 over the pressure range 100-800 Torr at a fixed value of density-normalized electric field, E/N, of 20 Td (1 Townsend = 10 -17 V cm 2 ). The data obtained show a clear dependence of the negative-ion drift velocity on drift distance. It is observed that the drift velocity (mobility) reaches a steady-state value only for drift distances above 2 cm, over the studied pressure range. In addition to this, we have observed that the ionic mobility depends strongly on the gas pressure. An explanation of this dependence of the ionic mobility on gas pressure is given in terms of a negative-ion clustering formation process. It was found that the assumption of a linear dependence of the cluster ion mass on pressure provides a satisfactory explanation for the observed mobilities.

  5. Stress and Negative Relationship Quality among Older Couples: Implications for Blood Pressure.

    Science.gov (United States)

    Birditt, Kira S; Newton, Nicky J; Cranford, James A; Ryan, Lindsay H

    2016-09-01

    The cardiovascular system may represent a significant pathway by which marriage and stress influence health, but research has focused on married individuals cross-sectionally. This study examined associations among chronic stress, negative spousal relationship quality, and systolic blood pressure over time among middle-aged and older husbands and wives. Participants were from the nationally representative longitudinal Health and Retirement Study. A total of 1,356 (N = 2,712) married and cohabitating couples completed psychosocial and biomeasure assessments in waves 2006 and 2010. Analyses examined whether Wave 1 (2006) relationship quality and stress were associated with changes in blood pressure over time. The effects of stress and negative relationship quality were dyadic and varied by gender. Husbands had increased blood pressure when wives reported greater stress, and this link was exacerbated by negative spousal relationship quality. Negative relationship quality predicted increased blood pressure when both members of the couple reported negative quality relations. Findings support the dyadic biopsychosocial model of marriage and health indicating: (a) stress and relationship quality directly effect the cardiovascular system, (b) relationship quality moderates the effect of stress, and (c) the dyad rather than only the individual should be considered when examining marriage and health. © The Author 2015. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  6. Perceiving social pressure not to feel negative predicts depressive symptoms in daily life.

    Science.gov (United States)

    Dejonckheere, Egon; Bastian, Brock; Fried, Eiko I; Murphy, Sean C; Kuppens, Peter

    2017-09-01

    Western societies often overemphasize the pursuit of happiness, and regard negative feelings such as sadness or anxiety as maladaptive and unwanted. Despite this emphasis on happiness, the amount of people suffering from depressive complaints is remarkably high. To explain this apparent paradox, we examined whether experiencing social pressure not to feel sad or anxious could in fact contribute to depressive symptoms. A sample of individuals (n = 112) with elevated depression scores (Patient Health Questionnaire [PHQ-9] ≥ 10) took part in an online daily diary study in which they rated their depressive symptoms and perceived social pressure not to feel depressed or anxious for 30 consecutive days. Using multilevel VAR models, we investigated the temporal relation between this perceived social pressure and depressive symptoms to determine directionality. Primary analyses consistently indicated that experiencing social pressure predicts increases in both overall severity scores and most individual symptoms of depression, but not vice versa. A set of secondary analyses, in which we adopted a network perspective on depression, confirmed these findings. Using this approach, centrality analysis revealed that perceived social pressure not to feel negative plays an instigating role in depression, reflected by the high out- and low instrength centrality of this pressure in the various depression networks. Together, these findings indicate how perceived societal norms may contribute to depression, hinting at a possible malignant consequence of society's denouncement of negative emotions. Clinical implications are discussed. © 2017 Wiley Periodicals, Inc.

  7. Negative magnetoresistance of pitch-based carbon fibers Temperature and pressure dependence

    Science.gov (United States)

    Hambourger, P. D.

    1986-01-01

    The negative transverse magnetoresistance of high-modulus pitch-based carbon fibers has been measured over the temperature range 1.3-4.2 K at ambient pressure and at 4.2 K under hydrostatic pressure up to 16 kbar. At low fields (less than 0.5 torr) the magnitude of the magnetoresistance increases markedly as the temperature is lowered from 4.2 K to 1.3 K, in disagreement with Bright's theoretical model, and decreases with pressure at the rate -0.6 percent/kbar.

  8. Using the Solving Problems Together Psychoeducational Group Counseling Model as an Intervention for Negative Peer Pressure

    Science.gov (United States)

    Hall, Kimberly R.; Rushing, Jeri Lynn; Khurshid, Ayesha

    2011-01-01

    Problem-focused interventions are considered to be one of the most effective group counseling strategies with adolescents. This article describes a problem-focused group counseling model, Solving Problems Together (SPT), that focuses on working with students who struggle with negative peer pressure. Adapted from the teaching philosophy of…

  9. Cost study of dermal substitutes and topical negative pressure in the surgical treatment of burns

    NARCIS (Netherlands)

    Hop, M.J.; Bloemen, M.C.T.; van Baar, M.E.; Nieuwenhuis, M.K.; van Zuijlen, P.P.M.; Polinder, S.; Middelkoop, E.

    2014-01-01

    AbstractBackground A recently performed randomised controlled trial investigated the clinical effectiveness of dermal substitutes (DS) and split skin grafts (SSG) in combination with topical negative pressure (TNP) in the surgical treatment of burn wounds. In the current study, medical and

  10. Pulse Waveform and Transcranial Doppler Analysis during Lower Body Negative Pressure

    Science.gov (United States)

    1993-04-01

    26, 23]. The application of negative pressure to the body for scientific or medical purposes was first used in 1841 by Junod , who used it to create a...localized hyperemia [26]. Junod also suggested that it could be used prior to invasive surgical procedures, since the syncope it was able to produce

  11. A systematic review of topical negative pressure therapy for acute and chronic wounds

    NARCIS (Netherlands)

    Ubbink, D. T.; Westerbos, S. J.; Nelson, E. A.; Vermeulen, H.

    2008-01-01

    Topical negative pressure (TNP) therapy is becoming increasingly popular for all kinds of wounds. Its clinical and cost effectiveness is unclear. A search of randomized controlled trials (RCTs) on TNP in adult patients with all kinds of wounds in all settings was undertaken in Medline, Embase,

  12. Improved wound management by regulated negative pressure-assisted wound therapy and regulated, oxygen- enriched negative pressure-assisted wound therapy through basic science research and clinical assessment

    Directory of Open Access Journals (Sweden)

    Moris Topaz

    2012-01-01

    Full Text Available Regulated negative pressure-assisted wound therapy (RNPT should be regarded as a state-of-the-art technology in wound treatment and the most important physical, nonpharmaceutical, platform technology developed and applied for wound healing in the last two decades. RNPT systems maintain the treated wound′s environment as a semi-closed, semi-isolated system applying external physical stimulations to the wound, leading to biological and biochemical effects, with the potential to substantially influence wound-host interactions, and when properly applied may enhance wound healing. RNPT is a simple, safe, and affordable tool that can be utilized in a wide range of acute and chronic conditions, with reduced need for complicated surgical procedures, and antibiotic treatment. This technology has been shown to be effective and safe, saving limbs and lives on a global scale. Regulated, oxygen-enriched negative pressure-assisted wound therapy (RO-NPT is an innovative technology, whereby supplemental oxygen is concurrently administered with RNPT for their synergistic effect on treatment and prophylaxis of anaerobic wound infection and promotion of wound healing. Understanding the basic science, modes of operation and the associated risks of these technologies through their fundamental clinical mechanisms is the main objective of this review.

  13. Novel cavitation fluid jet polishing process based on negative pressure effects.

    Science.gov (United States)

    Chen, Fengjun; Wang, Hui; Tang, Yu; Yin, Shaohui; Huang, Shuai; Zhang, Guanghua

    2018-04-01

    Traditional abrasive fluid jet polishing (FJP) is limited by its high-pressure equipment, unstable material removal rate, and applicability to ultra-smooth surfaces because of the evident air turbulence, fluid expansion, and a large polishing spot in high-pressure FJP. This paper presents a novel cavitation fluid jet polishing (CFJP) method and process based on FJP technology. It can implement high-efficiency polishing on small-scale surfaces in a low-pressure environment. CFJP uses the purposely designed polishing equipment with a sealed chamber, which can generate a cavitation effect in negative pressure environment. Moreover, the collapse of cavitation bubbles can spray out a high-energy microjet and shock wave to enhance the material removal. Its feasibility is verified through researching the flow behavior and the cavitation results of the negative pressure cavitation machining of pure water in reversing suction flow. The mechanism is analyzed through a computational fluid dynamics simulation. Thus, its cavitation and surface removal mechanisms in the vertical CFJP and inclined CFJP are studied. A series of polishing experiments on different materials and polishing parameters are conducted to validate its polishing performance compared with FJP. The maximum removal depth increases, and surface roughness gradually decreases with increasing negative outlet pressures. The surface becomes smooth with the increase of polishing time. The experimental results confirm that the CFJP process can realize a high material removal rate and smooth surface with low energy consumption in the low-pressure environment, together with compatible surface roughness to FJP. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Using portable negative pressure wound therapy devices in the home care setting

    Directory of Open Access Journals (Sweden)

    Burke JR

    2014-12-01

    Full Text Available Joshua R Burke, Rachael Morley, Mustafa Khanbhai Academic Surgery Unit, Education and Research Centre, University Hospital of South Manchester, Manchester, UK Abstract: Negative pressure wound therapy (NPWT is the continuous or intermittent application of subatmospheric pressure to the surface of a wound that improves the wound environment, accelerates healing, and reduces wound closure time. Since its first documented use, this technology has lent itself to a number of adaptations, most notably, the development of portable devices facilitating treatment in the home care setting. With advancing surgical standards, wound healing is an important rate-limiting factor in early patient discharge and often a major cost of inpatient treatment. The efficacy of NPWT in the home care setting has been investigated through rate of wound closure, time in care, and patient experience. Rate of wound closure is the most appropriate primary end point. Much can be gleaned from patient experience, but the future success of portable NPWT will be measured on time in care and therefore cost effectiveness. However, there is a lack of level 1a evidence demonstrating increased efficacy of portable over inpatient NPWT. The development of portable NPWT is an encouraging innovation in wound care technology, and extending the benefits to the home care setting is both possible and potentially more beneficial. Keywords: portable, negative pressure wound therapy, vacuum-assisted closure, topical negative pressure therapy

  15. The evidence-based principles of negative pressure wound therapy in trauma & orthopedics.

    Science.gov (United States)

    A, Novak; Khan, Wasim S; J, Palmer

    2014-01-01

    Negative pressure wound therapy is a popular treatment for the management of both acute and chronic wounds. Its use in trauma and orthopedics is diverse and includes the acute traumatic setting as well as chronic troublesome wounds associated with pressure sores and diabetic foot surgery. Efforts have been made to provide an evidence base to guide its use however this has been limited by a lack of good quality evidence. The following review article explores the available evidence and describes future developments for its use in trauma and orthopaedic practice.

  16. Early activation of the coagulation system during lower body negative pressure

    DEFF Research Database (Denmark)

    Zaar, M; Johansson, P I; Nielsen, L B

    2009-01-01

    We considered that a moderate reduction of the central blood volume (CBV) may activate the coagulation system. Lower body negative pressure (LBNP) is a non-invasive means of reducing CBV and, thereby, simulates haemorrhage. We tested the hypothesis that coagulation markers would increase following...... moderate hypovolemia by exposing 10 healthy male volunteers to 10 min of 30 mmHg LBNP. Thoracic electrical impedance increased during LBNP (by 2.6 +/- 0.7 Omega, mean +/- SD; P pressure decreased (84 +/- 5 to 80...

  17. Head holder using negative pressure bag packed with plastic beads in xenon CT CBF study

    International Nuclear Information System (INIS)

    Araki, Yuzo; Sakai, Noboru

    2003-01-01

    Employing analysis of cerebral blood flow (CBF) confidence maps, we investigated the usefulness of a head holder using a negative pressure bag packed with plastic beads in a xenon CT CBF study. A total of 272 consecutive patients for the CBF study were enrolled and classified into 3 groups: 88 patients with a negative pressure bag (M group), 87 patients with an air pillow (A group), and 97 patients with a sponge pillow (S group). The degree of effect of head movements on the CBF measurement in each patient was expressed as a confidence value (mean of the confidence values at one CT slice). The mean of confidence value in the M group (0.461) was statistically lower than that in the A group (0.866) and that in the S group (1.043). These findings showed that the head holder described here was useful for obtaining CBF maps of high quality in a xenon CT CBF study. (author)

  18. Negative pressure darwinism: survival of the fittest paradigm.

    Science.gov (United States)

    Miller, Michael; Bybordi, Farhad

    2009-07-01

    The use of negative pressure for wound healing has been based on a set of parameters and devices that until recently were combined into a single paradigm. Despite historical and more recent evidence providing viable alternative considerations, it is only recently that this paradigm and its tenets have come into question. As the understanding of the limits of the current paradigm and specific instances of its benefits and drawbacks are identified, shifts in the paradigm must take place if the therapy is to evolve, develop, and continue to be efficacious. The pertinence of the concept of survival of the fittest is used to explore the need for a paradigm shift in negative pressure wound therapy.

  19. Negative Gauge Pressure Moisture Management and Secure Adherence Device for Prosthetic Limbs

    Science.gov (United States)

    2013-03-01

    prosthesis feels like it is sliding up and down or falling off when I am active. D. I have been more active than normal as a result of this prosthesis ...temperature. 3. My prosthesis feels like it is sliding up and down or falling off when I am active. 4. I have been more active than normal as a result of...objective of this research was to develop and test a novel prosthesis incorporating a negative gauge pressure moisture management and secure

  20. Histomorphological observation of surgical debridement combined with negative pressure therapy in treatment of diabetic foot

    Directory of Open Access Journals (Sweden)

    Jiao-Yun Dong

    2017-08-01

    Conclusion: Epidermal cells on the fascia side of the flap could be derived from the stem cells. Negative pressure wound therapy would attract not only cells but also other elements such as growth factors, cytokines, some nutrients and extracellular matrix. With the formation of the appropriate microenvironment after debridement, the migrated cells can grow, differentiate and spread, eventually leading to the epithelization on the fascia side of the flap in diabetic foot.

  1. Facets of negative affectivity and blood pressure in middle-aged men

    Directory of Open Access Journals (Sweden)

    Cornel V. Igna

    2013-04-01

    Full Text Available Research results suggesting that facets of negative affectivity, i.e. anxiety, anger-hostility, and depression, relate to incident cardiovascular diseases have been steadily increasing. Evidence for depression has been especially extensive. Elevated blood pressure, a major risk factor of cardiovascular diseases, is one probable mediator in this context. The purpose of this study was to clarify the relationship of specific key elements of depressive disposition, i.e. depressive symptoms, hopelessness and vital exhaustion, with health behavior and blood pressure. Study sample was comprised of 710 middle-aged men. Participants completed self-report questionnaires assessing health behavior, depressive symptoms, vital exhaustion and hopelessness. Statistical analyses involved descriptive analyses, correlations and path analysis. Depressive symptoms and vital exhaustion associated with several unfavorable lifestyles such as smoking, alcohol consumption, and inactivity (standardized solution coefficients: 0.10, 0.14, 0.17, accordingly. However, no significant direct associations with blood pressure could be found for depressive symptoms or vital exhaustion. Hopelessness associated only with unhealthy diet (standardized solution coefficient -0.10 Moreover, for hopelessness, results showed a direct but inverse association with systolic blood pressure (standardized solution coefficient -0.08. Results suggest that the previously reported relations of depression and vital exhaustion with blood pressure could be mediated by unfavorable lifestyles. The relation of hopelessness with adverse health behaviors seems to be less significant. Also, the role of hopelessness as a risk factor of elevated blood pressure is not supported by the results of this study.

  2. Using negative pressure therapy for improving skin graft taking on genital area defects following Fournier gangrene.

    Science.gov (United States)

    Orhan, Erkan; Şenen, Dilek

    2017-09-01

    Fournier's gangrene is an infective necrotizing fasciitis of the perineal, genital and perianal regions. Treatment includes aggressive surgical debridement that often results in extensive loss of genital skin. Skin grafts may be used for reconstruction but skin grafting of the male genitalia is diffucult because the penis and scrotum are mobile and deformable. A variety of methods are used to secure skin graft to recipient beds. We used negative pressure therapy (NPT) to secure skin grafts and improve skin graft taking. We used negative pressure therapy for graft fixation in 13 male patients who underwent debridements with the indication of Fournier gangrene, and whose defects formed were reconstructed with grafts between January 2009, and January 2014. Information about age of the patients, sessions of negative pressure therapy applied before, and after reconstruction, duration of hospital stay, and graft losses during postoperative period were recorded. Median age of the patients was 56.15 (46-72) years. NPT was applied to patients for an average of 6.64 sessions (4-12) before and 1 sessions after graft reconstruction. Patients were hospitalized for an average of 26.7 (20-39) days. Any graft loss was not seen after NPT. Because of the peculiar anatomy of the genital region, anchoring of grafts is difficult so graft losses are often encountered. Use of NPT for ensuring graft fixation on the genital region prevents skin graft shearing.

  3. Negative pressure pulmonary edema after nasal fracture reduction in an obese female patient: a case report

    Directory of Open Access Journals (Sweden)

    Choi EK

    2015-08-01

    Full Text Available Eunkyung Choi,1 Junggu Yi,1 Younghoon Jeon,2 1Department of Anesthesiology and Pain Medicine, School of Medicine, Kyungpook National University, Daegu, Republic of Korea; 2Department of Anesthesiology and Pain Medicine, School of Dentistry, Kyungpook National University, Daegu, Republic of Korea Abstract: Postoperative negative pressure pulmonary edema (NPPE is a rare, but well-known life-threatening complication of acute upper airway obstruction (UAO which develops after general anesthesia. The pronounced inspiratory efforts following UAO lead to excessive negative inspiratory pressure, which may cause acute pulmonary edema. Early recognition and prompt treatment of NPPE is necessary to prevent patient morbidity and mortality. In addition, the physician should carefully manage the patient who has risk factors of UAO to prevent this situation. We experienced a case of NPPE following laryngospasm after tracheal extubation in an obese patient who underwent open reduction of orbital wall and nasal bone surgery. Keywords: airway obstruction, negative pressure pulmonary edema, laryngospasm, nasal surgery, obese

  4. Negative Pressures and the First Water Siphon Taller than 10.33 Meters.

    Directory of Open Access Journals (Sweden)

    Francisco Vera

    Full Text Available A siphon is a device that is used to drain a container, with water rising inside a hose in the form of an inverted U and then going down towards a discharge point placed below the initial water level. The siphon is the first of a number of inventions of the ancients documented about 2.000 years ago by Hero of Alexandria in his treatise Pneumatics, and although the explanation given by Hero was essentially correct, there is nowadays a controversy about the underlying mechanism that explains the working of this device. Discussions concerning the physics of a siphon usually refer to concepts like absolute negative pressures, the strength of liquid's cohesion and the possibility of a siphon working in vacuum or in the presence of bubbles. Torricelli understood the working principle of the barometer and the impossibility of pumping water out of wells deeper than 10.33 m. Following Torricelli's ideas it would also not be possible to build a siphon that drives pure water to ascend higher than 10.33 m. In this work, we report the first siphon that drives water (with surfactant to ascend higher than the Torricellian limit. Motivated by the rising of sap in trees, we built a 15.4 m siphon that shows that absolute negative pressures are not prohibited, that cohesion plays an important role in transmitting forces through a fluid, and that surfactants can help to the transport of water in a metastable regime of negative pressures.

  5. A pilot randomised controlled trial of negative pressure wound therapy to treat grade III/IV pressure ulcers [ISRCTN69032034

    Science.gov (United States)

    2012-01-01

    Background Negative pressure wound therapy (NPWT) is widely promoted as a treatment for full thickness wounds; however, there is a lack of high-quality research evidence regarding its clinical and cost effectiveness. A trial of NPWT for the treatment of grade III/IV pressure ulcers would be worthwhile but premature without assessing whether such a trial is feasible. The aim of this pilot randomised controlled trial was to assess the feasibility of conducting a future full trial of NPWT for the treatment of grade III and IV pressure ulcers and to pilot all aspects of the trial. Methods This was a two-centre (acute and community), pilot randomised controlled trial. Eligible participants were randomised to receive either NPWT or standard care (SC) (spun hydrocolloid, alginate or foam dressings). Outcome measures were time to healing of the reference pressure ulcer, recruitment rates, frequency of treatment visits, resources used and duration of follow-up. Results Three hundred and twelve patients were screened for eligibility into this trial over a 12-month recruitment period and 12/312 participants (3.8%) were randomised: 6 to NPWT and 6 to SC. Only one reference pressure ulcer healed (NPWT group) during follow-up (time to healing 79 days). The mean number of treatment visits per week was 3.1 (NPWT) and 5.7 (SC); 6/6 NPWT and 1/6 SC participants withdrew from their allocated trial treatment. The mean duration of follow-up was 3.8 (NPWT) and 5.0 (SC) months. Conclusions This pilot trial yielded vital information for the planning of a future full study including projected recruitment rate, required duration of follow-up and extent of research nurse support required. Data were also used to inform the cost-effectiveness and value of information analyses, which were conducted alongside the pilot trial. Trial registration Current Controlled Trials ISRCTN69032034. PMID:22839453

  6. A pilot randomised controlled trial of negative pressure wound therapy to treat grade III/IV pressure ulcers [ISRCTN69032034

    Directory of Open Access Journals (Sweden)

    Ashby Rebecca L

    2012-07-01

    Full Text Available Abstract Background Negative pressure wound therapy (NPWT is widely promoted as a treatment for full thickness wounds; however, there is a lack of high-quality research evidence regarding its clinical and cost effectiveness. A trial of NPWT for the treatment of grade III/IV pressure ulcers would be worthwhile but premature without assessing whether such a trial is feasible. The aim of this pilot randomised controlled trial was to assess the feasibility of conducting a future full trial of NPWT for the treatment of grade III and IV pressure ulcers and to pilot all aspects of the trial. Methods This was a two-centre (acute and community, pilot randomised controlled trial. Eligible participants were randomised to receive either NPWT or standard care (SC (spun hydrocolloid, alginate or foam dressings. Outcome measures were time to healing of the reference pressure ulcer, recruitment rates, frequency of treatment visits, resources used and duration of follow-up. Results Three hundred and twelve patients were screened for eligibility into this trial over a 12-month recruitment period and 12/312 participants (3.8% were randomised: 6 to NPWT and 6 to SC. Only one reference pressure ulcer healed (NPWT group during follow-up (time to healing 79 days. The mean number of treatment visits per week was 3.1 (NPWT and 5.7 (SC; 6/6 NPWT and 1/6 SC participants withdrew from their allocated trial treatment. The mean duration of follow-up was 3.8 (NPWT and 5.0 (SC months. Conclusions This pilot trial yielded vital information for the planning of a future full study including projected recruitment rate, required duration of follow-up and extent of research nurse support required. Data were also used to inform the cost-effectiveness and value of information analyses, which were conducted alongside the pilot trial. Trial registration Current Controlled Trials ISRCTN69032034.

  7. Lower body negative pressure as a tool for research in aerospace physiology and military medicine

    Science.gov (United States)

    Convertino, V. A.

    2001-01-01

    Lower body negative pressure (LBNP) has been extensively used for decades in aerospace physiological research as a tool to investigate cardiovascular mechanisms that are associated with or underlie performance in aerospace and military environments. In comparison with clinical stand and tilt tests, LBNP represents a relatively safe methodology for inducing highly reproducible hemodynamic responses during exposure to footward fluid shifts similar to those experienced under orthostatic challenge. By maintaining an orthostatic challenge in a supine posture, removal of leg support (muscle pump) and head motion (vestibular stimuli) during LBNP provides the capability to isolate cardiovascular mechanisms that regulate blood pressure. LBNP can be used for physiological measurements, clinical diagnoses and investigational research comparisons of subject populations and alterations in physiological status. The applications of LBNP to the study of blood pressure regulation in spaceflight, groundbased simulations of low gravity, and hemorrhage have provided unique insights and understanding for development of countermeasures based on physiological mechanisms underlying the operational problems.

  8. Negative-pressure and low-pressure hydrocephalus: the role of cerebrospinal fluid leaks resulting from surgical approaches to the cranial base.

    Science.gov (United States)

    Filippidis, Aristotelis S; Kalani, M Yashar S; Nakaji, Peter; Rekate, Harold L

    2011-11-01

    Negative-pressure and low-pressure hydrocephalus are rare clinical entities that are frequently misdiagnosed. They are characterized by recurrent episodes of shunt failure because the intracranial pressure is lower than the opening pressure of the valve. In this report the authors discuss iatrogenic CSF leaks as a cause of low- or negative-pressure hydrocephalus after approaches to the cranial base. The authors retrospectively reviewed cases of low-pressure or negative-pressure hydrocephalus presenting after cranial approaches complicated with a CSF leak at their institution. Three patients were identified. Symptoms of high intracranial pressure and ventriculomegaly were present, although the measured pressures were low or negative. A blocked communication between the ventricles and the subarachnoid space was documented in 2 of the cases and presumed in the third. Shunt revisions failed repeatedly. In all cases, temporary clinical and radiographic improvement resulted from external ventricular drainage at subatmospheric pressures. The CSF leaks were sealed and CSF communication was reestablished operatively. In 1 case, neck wrapping was used with temporary success. Negative-pressure or low-pressure hydrocephalus associated with CSF leaks, especially after cranial base approaches, is difficult to treat. The solution often requires the utilization of subatmospheric external ventricular drains to establish a lower ventricular drainage pressure than the drainage pressure created in the subarachnoid space, where the pressure is artificially lowered by the CSF leak. Treatment involves correction of the CSF leak, neck wrapping to increase brain turgor and allow the pressure in the ventricles to rise to the level of the opening pressure of the valve, and reestablishing the CSF route.

  9. Evaluation of negative pressure vacuum-assisted system in acute and chronic wounds closure: our experience.

    Science.gov (United States)

    Chiummariello, S; Guarro, G; Pica, A; Alfano, C

    2012-10-01

    Negative-pressure therapy or vacuum-assisted closure (VAC) has been used in clinical applications since the 1940's and has increased in popularity over the past decade. This dressing technique consists of an open cell foam dressing put into the wound cavity, a vacuum pump produces a negative pressure and an adhesive drape. A controlled sub atmospheric pressure from 75 to 150 mmHg is applied. The vacuum-assisted closure has been applied by many clinicians to chronic wounds in humans; however it cannot be used as a replacement for surgical debridement. The initial treatment for every contaminated wound should be the necrosectomy. The VAC therapy has a complementary function and the range of its indications includes pressure sores, stasis ulcers, chronic wounds such as diabetic foot ulcers, post traumatic and post operative wounds, infected wounds such as necrotizing fasciitis or sternal wounds, soft-tissue injuries, bone exposed injuries, abdominal open wounds and for securing a skin graft. We describe our experience with the VAC dressing used to manage acute and chronic wounds in a series of 135 patients, with excellent results together with satisfaction of the patients.

  10. Differential effects of lower body negative pressure and upright tilt on splanchnic blood volume

    Science.gov (United States)

    Taneja, Indu; Moran, Christopher; Medow, Marvin S.; Glover, June L.; Montgomery, Leslie D.; Stewart, Julian M.

    2015-01-01

    Upright posture and lower body negative pressure (LBNP) both induce reductions in central blood volume. However, regional circulatory responses to postural changes and LBNP may differ. Therefore, we studied regional blood flow and blood volume changes in 10 healthy subjects undergoing graded lower-body negative pressure (−10 to −50 mmHg) and 8 subjects undergoing incremental head-up tilt (HUT; 20°, 40°, and 70°) on separate days. We continuously measured blood pressure (BP), heart rate, and regional blood volumes and blood flows in the thoracic, splanchnic, pelvic, and leg segments by impedance plethysmography and calculated regional arterial resistances. Neither LBNP nor HUT altered systolic BP, whereas pulse pressure decreased significantly. Blood flow decreased in all segments, whereas peripheral resistances uniformly and significantly increased with both HUT and LBNP. Thoracic volume decreased while pelvic and leg volumes increased with HUT and LBNP. However, splanchnic volume changes were directionally opposite with stepwise decreases in splanchnic volume with LBNP and stepwise increases in splanchnic volume during HUT. Splanchnic emptying in LBNP models regional vascular changes during hemorrhage. Splanchnic filling may limit the ability of the splanchnic bed to respond to thoracic hypovolemia during upright posture. PMID:17085534

  11. Timer switch to convert suction apparatus for negative pressure wound therapy application

    Directory of Open Access Journals (Sweden)

    Surath Amarnath

    2014-01-01

    Full Text Available Background: Negative pressure wound therapy (NPWT is an established modality in the treatment of chronic wounds, open fractures, and post-operative wound problems. This method has not been widely used due to the high cost of equipment and consumables. This study demonstrates an indigenously developed apparatus which gives comparable results at a fraction of the cost. Readily available materials are used for the air-tight dressing. Materials and Methods: Equipment consists of suction apparatus with adjustable pressure valve set to a pressure 125-150 mmHg. An electronic timer switch with a sequential working time of 5 min and a standby time of 3 min provides the required intermittent negative pressure. Readily available materials such as polyvinyl alcohol sponge, suction drains and steridrapes were used to provide an air tight wound cover. Results: A total of 90 cases underwent 262 NPWT applications from 2009 to 2014. This series, comprised of 30 open fractures, 21 post-operative and 39 chronic wounds. The wound healing rate in our study was comparable to other published studies using NPWT. Conclusion: The addition of electronic timer switch will convert a suction apparatus into NPWT machine, and the results are equally effective compared to more expensive counter parts. The use of indigenous dressing materials reduces the cost significantly.

  12. Mini Treadmill for Musculoskeletal Health

    Science.gov (United States)

    Humphreys, Bradley

    2015-01-01

    Because NASA's approach to space exploration calls for long-term extended missions, there is a pressing need to equip astronauts with effective exercise regimens that will maintain musculoskeletal and cardiovascular health. ZIN Technologies, Inc., has developed an innovative miniature treadmill for use in both zero-gravity and terrestrial environments. The treadmill offers excellent periodic impact exercise to stimulate cardiovascular activity and bone remodeling as well as resistive capability to encourage full-body muscle maintenance. A novel speed-control algorithm allows users to modulate treadmill speed by adjusting stride, and a new subject load device provides a more Earth-like gravity replacement load. This new and compact treadmill offers a unique approach to managing astronaut health while addressing the inherent and stringent challenges of space flight. The innovation also has the potential to offer numerous terrestrial applications, as a real-time daily load stimulus (DLS) measurement feature provides an effective mechanism to combat or manage osteoporosis, a major public health threat for 55 percent of Americans over the age of 50.

  13. Patients' experiences of negative pressure wound therapy for the treatment of wounds: a review.

    Science.gov (United States)

    Upton, D; Stephens, D; Andrews, A

    2013-01-01

    To review the research on patients' experiences of undergoing negative pressure wound therapy (NPWT). A literature search was carried out using the following databases: Academic Search Complete, CINAHL, PsychINFO, MEDLINE, PubMed and PsyARTICLES. The search covered the period from 2001 to 2012, using the key words: ['negative pressure wound therapy' OR 'vacuum-assisted closure' OR 'topical negative therapy'] AND ['patients' experiences' OR 'psychological' OR 'stress' OR 'anxiety' OR 'wellbeing' OR 'pain' OR 'quality of life' OR 'physical']. Twenty-five relevant articles were included. NPWT is generally considered to be successful in reducing wound depth and facilitating healing. However, studies have highlighted a number of issues that need to be considered. For example, the type of dressing used during treatment can have a significant effect on patients' experience of pain. Furthermore, the NPWT system can cause patients to feel anxious due to both the patient and the health professional being unfamiliar with this form of treatment. It can also restrict patients' daily care and wider social life, which may result in a negative self-image and low self-esteem. Despite this, some studies have reported positive improvements to patients' quality of life. Additionally, since NPWT can lead to faster healing, any detrimental impact upon patients' wellbeing may be short-term and less prolonged than that of other treatments. Compared with other treatments, there is evidence to show that NPWT can lead to faster wound healing, and a reduced frequency of dressing changes and other treatments. However, there are a number of challenges with the use of NPWT, which need to be explored further so that improvements can be made. Specifically, certain aspects of NPWT may impact negatively on patients' wellbeing, albeit short-term. Therefore, research needs to explore patients' experience of NPWT throughout the treatment process and to consider how this can be improved to minimise any

  14. Negative pressure wound therapy for the treatment of infected wounds with exposed knee joint after patellar fracture.

    Science.gov (United States)

    Lee, Sang Yang; Niikura, Takahiro; Miwa, Masahiko; Sakai, Yoshitada; Oe, Keisuke; Fukazawa, Takahiro; Kawakami, Yohei; Kurosaka, Masahiro

    2011-06-14

    Treatment of soft tissue defects with exposed bones and joints, resulting from trauma, infection, and surgical complications, represents a major challenge. The introduction of negative pressure wound therapy has changed many wound management practices. Negative pressure wound therapy has recently been used in the orthopedic field for management of traumatic or open wounds with exposed bone, nerve, tendon, and orthopedic implants. This article describes a case of a patient with a large soft tissue defect and exposed knee joint, in which negative pressure wound therapy markedly improved wound healing. A 50-year-old man presented with an ulceration of his left knee with exposed joint, caused by severe wound infections after open reduction and internal fixation of a patellar fracture. After 20 days of negative pressure wound therapy, a granulated wound bed covered the exposed bones and joint.To our knowledge, this is the first report of negative pressure wound therapy used in a patient with a large soft tissue defect with exposed knee joint. Despite the chronic wound secondary to infection, healing was achieved through the use of the negative pressure wound therapy, thus promoting granulation tissue formation and closing the joint. We suggest negative pressure wound therapy as an alternative option for patients with lower limb wounds containing exposed bones and joints when free flap transfer is contraindicated. Our result added to the growing evidence that negative pressure wound therapy is a useful adjunctive treatment for open wounds around the knee joint. Copyright 2011, SLACK Incorporated.

  15. Abdominal compartment syndrome and open abdomen management with negative pressure devices.

    Science.gov (United States)

    Surace, Alessandra; Ferrarese, Alessia; Marola, Silvia; Cumbo, Jacopo; Valentina, Gentile; Borello, Alessandro; Solej, Mario; Martino, Valter; Nano, Mario

    2015-01-01

    Abdominal compartment syndrome (ACS) is defined as an increase of intra-abdominal pressure (IAH) to values higher than 20 mmHg, associated with reduced perfusion and organ dysfunction. There is a classification of open abdomen which stratifies patients according to the natural history of improvement or clinical deterioration. The aim of treatment is to maintain the open abdomen at the lowest level and to prevent progression to a more complex level. Surgical treatment essentially consists in abdominal decompression by leaving the abdomen open. Analysis of the literature shows that negative pressure increases the rate of primary fascial closure; entero-cutaneous fistulas are seen in a minority of cases, without seeming consequence of the application of the dressing. Open abdomen management consists of three treatment stages: acute (24-48 hours), intermediate (from 48 hours to 10 days) and late or reconstruction (from 10 days to the final closure). It's important to recognize patients at risk of IAH and the first signs of ACS and intervene early with abdominal decompression if this will establish itself. Management of the open abdomen is now facilitated by negative pressure devices, which positively affect the morbidity and mortality of patients with ACS.

  16. Increased serum urea to creatinine ratio and its negative correlation with arterial pressure in canine babesiosis.

    Science.gov (United States)

    Zygner, Wojciech; Gójska-Zygner, Olga

    2014-09-01

    The increase of the serum urea to creatinine ratio (UCR) was observed in dogs infected with Babesia canis. Previous studies have suggested that decrease of blood pressure can be one of the reasons for this phenomenon. In this work statistically significant increase of the UCR was observed in dogs with babesiosis. Comparison of the UCR between 23 azotaemic dogs and 25 non-azotaemic dogs infected with Babesia canis showed statistically significantly higher mean of the UCR in azotaemic dogs. Correlations between UCR and systolic, diastolic and mean arterial pressure (SAP, DAP and MAP) in 48 dogs infected with B. canis were negative (UCR and SAP: r = -0.3909; UCR and DAP: r = -0.3182; UCR and MAP: r = -0.3682) and statistically significant (p high, and there was no statistically significant correlation between UCR and arterial pressures in azotaemic dogs. Thus, it seems that decrease of blood pressure in dogs with babesiosis explains only partially the cause of increased UCR in infected dogs. The other authors suggested hyperureagenesis and myocardial injury as a potential reason for the increased UCR in canine babesiosis. Thus, further studies are needed to determine causes of increased UCR in dogs with babesiosis, especially on the connection between UCR changes and the concentrations of plasma cardiac troponins and ammonia, and the occurrence of occult blood on fecal examination.

  17. Hemodynamic differences between continual positive and two types of negative pressure ventilation.

    Science.gov (United States)

    Lockhat, D; Langleben, D; Zidulka, A

    1992-09-01

    In seven anesthetized dogs, ventilated with matching lung volumes, tidal volumes, and respiratory rates, we compared the effects on cardiac output (CO), arterial venous oxygen saturation difference (SaO2 - SVO2), and femoral and inferior vena cava pressure (1) intermittent positive pressure ventilation with positive end-expiratory pressure (CPPV); (2) iron-lung ventilation with negative end-expiratory pressure (ILV-NEEP); (3) grid and wrap ventilation with NEEP applied to the thorax and upper abdomen (G&W-NEEP). The values of CO and SaO2 - SVO2 with ILV-NEEP were similar to those with CPPV. However, with G&W-NEEP as compared with ILV-NEEP, mean CO was greater (2.9 versus 2.6 L/min, p = 0.02) and mean (SaO2 - SVO2) was lower (26.6% versus 28.3%, p = NS). Mean PFEM-IVC was higher with G&W-NEEP than with the other types of ventilation. We conclude that (1) ILV-NEEP is hemodynamically equivalent to CPPV and (2) G&W-NEEP has less adverse hemodynamic consequences. has less adverse hemodynamic consequences.

  18. Interrogative pressure in simulated forensic interviews: the effects of negative feedback.

    Science.gov (United States)

    McGroarty, Allan; Baxter, James S

    2007-08-01

    Much experimental research on interrogative pressure has concentrated on the effects of leading questions, and the role of feedback in influencing responses in the absence of leading questions has been neglected by comparison. This study assessed the effect of negative feedback and the presence of a second interviewer on interviewee responding in simulated forensic interviews. Participants viewed a videotape of a crime, answered questions about the clip and were requestioned after receiving feedback. Compared with neutral feedback, negative feedback resulted in more response changes, higher reported state anxiety and higher ratings of interview difficulty. These results are consistent with Gudjonsson and Clark's (1986) model of interrogative suggestibility. The presence and involvement of a second interviewer did not significantly affect interviewee responding, although trait anxiety scores were elevated when a second interviewer was present. The theoretical and applied implications of these findings are considered.

  19. Technical specifications of variable speed motors for negative pressure control in hot cell area

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seon Duk; Bang, H. S.; Cho, W. K

    2002-01-01

    Hot cells are the facilities for handling the high radioactive materials and various R and D activities are performed using hot cells. Therefore the control of air flow in hot cell area is very important technology and it is started with the variable speed motor(VSM) controlling the air handling system in that area. This report describes various technical aspects of VS motors and will be useful for understanding the practical technologies of VS motors and also for optimization of the negative pressure controls in hot cell area.

  20. Temporal evolution of atmosphere pressure plasma jets driven by microsecond pulses with positive and negative polarities

    Science.gov (United States)

    Shao, Tao; Yang, Wenjin; Zhang, Cheng; Fang, Zhi; Zhou, Yixiao; Schamiloglu, Edl

    2014-09-01

    Current-voltage characteristics, discharge images, and optical spectra of atmospheric pressure plasma jets (APPJs) are studied using a microsecond pulse length generator producing repetitive output pulses with different polarities. The experimental results show that the APPJs excited by the pulses with positive polarity have longer plume, faster propagation speed, higher power, and more excited species, such as \\text{N}2 , O, He, \\text{N}2+ , than that with the negatively excited APPJs. The images taken using an intensified charge-coupled device show that the APPJs excited by pulses with positive polarity are characterized by a bullet-like structure, while the APPJs excited by pulses with negative polarity are continuous. The propagation speed of the APPJs driven by a microsecond pulse length generator is about tens of km/s, which is similar to the APPJs driven by a kHz frequency sinusoidal voltage source. The analysis shows that the space charge accumulation effect plays an important role during the discharge. The transient enhanced electric field induced by the accumulated ions between the needle-like electrode and the nozzle in the APPJs excited by pulses with negative polarity enhances electron field emission from the cathode, which is illustrated by the bright line on the time-integrated images. This makes the shape of the APPJ excited using pulses with negative polarity different from the bullet-like shape of the APPJs excited by pulses with positive polarity.

  1. Flame Atmospheric Pressure Chemical Ionization Coupled with Negative Electrospray Ionization Mass Spectrometry for Ion Molecule Reactions.

    Science.gov (United States)

    Cheng, Sy-Chyi; Bhat, Suhail Muzaffar; Shiea, Jentaie

    2017-07-01

    Flame atmospheric pressure chemical ionization (FAPCI) combined with negative electrospray ionization (ESI) mass spectrometry was developed to detect the ion/molecule reactions (IMRs) products between nitric acid (HNO 3 ) and negatively charged amino acid, angiotensin I (AI) and angiotensin II (AII), and insulin ions. Nitrate and HNO 3 -nitrate ions were detected in the oxyacetylene flame, suggesting that a large quantity of nitric acid (HNO 3 ) was produced in the flame. The HNO 3 and negatively charged analyte ions produced by a negative ESI source were delivered into each arm of a Y-shaped stainless steel tube where they merged and reacted. The products were subsequently characterized with an ion trap mass analyzer attached to the exit of the Y-tube. HNO 3 showed the strongest affinity to histidine and formed (M histidine -H+HNO 3 ) - complex ions, whereas some amino acids did not react with HNO 3 at all. Reactions between HNO 3 and histidine residues in AI and AII resulted in the formation of dominant [M AI -H+(HNO 3 )] - and [M AII -H+(HNO 3 )] - ions. Results from analyses of AAs and insulin indicated that HNO 3 could not only react with basic amino acid residues, but also with disulfide bonds to form [M-3H+(HNO 3 ) n ] 3- complex ions. This approach is useful for obtaining information about the number of basic amino acid residues and disulfide bonds in peptides and proteins. Graphical Abstract ᅟ.

  2. Formation and Morphology Evolution of Anodic TiO2 Nanotubes under Negative Pressure

    International Nuclear Information System (INIS)

    Lu, Hongyan; Fan, Haowen; Jin, Rong; Chong, Bin; Shen, Xiaoping; Yan, Shuo; Zhu, Xufei

    2016-01-01

    Highlights: • Nernst equation is applied to explain electrochemical reactions during anodization. • Longer nanotubes were obtained under 0.02 MPa, as compared to atmospheric conditions. • The total anodizing current was separated into ionic current and electronic current. • Explanation for the particularity of nanotubes obtained under 0.02 MPa is presented. - Abstract: Anodic TiO 2 nanotubes (ATNTs) have attracted extensive interest in the past decade. ATNTs are generally fabricated by anodization of Ti foils under atmospheric conditions (0.1 MPa). To date, the growth kinetics of ATNTs remains unclear. Herein anodizations of Ti foils under negative pressure are designed to overcome this challenge. Longer nanotubes were fabricated under negative pressure, as compared to atmospheric conditions. Variations of the nanotube length and surface morphology of ATNTs provide evidences for oxygen bubble mould, in which the ionic current contributes to nanotube growth while the electronic current gives rise to the oxygen evolution. Nernst equation was firstly applied to simulate variations of electronic current and ionic current during anodization. The in-depth analysis of the morphology variations could help elucidate the formation mechanism, thus paving the way for the optimization of the synthesis process of ATNTs.

  3. Matching Biological Mesh and Negative Pressure Wound Therapy in Reconstructing an Open Abdomen Defect

    Directory of Open Access Journals (Sweden)

    Fabio Caviggioli

    2014-01-01

    Full Text Available Reconstruction of open abdominal defects is a clinical problem which general and plastic surgeons have to address in cooperation. We report the case of a 66-year-old man who presented an abdominal dehiscence after multiple laparotomies for a sigmoid-rectal adenocarcinoma that infiltrated into the abdominal wall, subsequently complicated by peritonitis and enteric fistula. A cutaneous dehiscence and an incontinent abdominal wall resulted after the last surgery. The abdominal wall was reconstructed using a biological porcine cross-linked mesh Permacol (Covidien Inc., Norwalk, CT. Negative Pressure Wound Therapy (NPWT, instead, was used on the mesh in order to reduce wound dimensions, promote granulation tissue formation, and obtain secondary closure of cutaneous dehiscence which was finally achieved with a split-thickness skin graft. Biological mesh behaved like a scaffold for the granulation tissue that was stimulated by the negative pressure. The biological mesh was rapidly integrated in the abdominal wall restoring abdominal wall continence, while the small dehiscence, still present in the central area, was subsequently covered with a split-thickness skin graft. The combination of these different procedures led us to solve this complicated case obtaining complete wound closure after less than 2 months.

  4. An Alternative Treatment Strategy for Complicated Chronic Wounds: Negative Pressure Therapy over Mesh Skin Graft

    Directory of Open Access Journals (Sweden)

    Michele Maruccia

    2017-01-01

    Full Text Available Extensive skin defect represents a real problem and major challenge in plastic and reconstructive surgery. On one hand, skin grafts offer a practical method to deal with skin defects despite their unsuitability for several complicated wounds. On the other hand, negative pressure wound therapy (NPWT, applied before skin grafting, promotes granulation tissue growth. The aim of the study is to evaluate the improvement in wound healing given by the merger of these two different approaches. We treated 23 patients for large wounds of multiple factors. Of these, 15 were treated with the application of V.A.C.® Therapy (KCI Medical S.r.l., Milan, Italy, in combination with skin grafts after a prior unsuccessful treatment of 4 weeks with mesh skin grafts and dressings. Another 8 were treated with only mesh skin graft. Pain reduction and wound area reduction were found statistically significant (p<0.0009, p<0.0001. Infection was resolved in almost all patients. According to our study, the use of the negative pressure wound therapy over mesh skin grafts is significantly effective especially in wounds resistant to conventional therapies, thereby improving the rate of skin graft take.

  5. Negative pressure therapy (vacuum for wound bed preparation among diabetic patients: case series

    Directory of Open Access Journals (Sweden)

    Marcus Castro Ferreira

    Full Text Available CONTEXT: Complications from diabetes mellitus affecting the lower limbs occur in 40 to 70% of such patients. Neuropathy is the main cause of ulceration and may be associated with vascular impairment. The wound evolves with necrosis and infection, and if not properly treated, amputation may be the end result. Surgical treatment is preferred in complex wounds without spontaneous healing. After debridement of the necrotic tissue, the wound bed needs to be prepared to receive a transplant of either a graft or a flap. Dressings can be used to prepare the wound bed, but this usually leads to longer duration of hospitalization. Negative pressure using a vacuum system has been proposed for speeding up the treatment. This paper had the objective of analyzing the effects of this therapy on wound bed preparation among diabetic patients. CASE SERIES: Eighty-four diabetic patients with wounds in their lower limbs were studied. A commercially available vacuum system was used for all patients after adequate debridement of necrotic tissues. For 65 patients, skin grafts completed the treatment and for the other 19, skin flaps were used. Wound bed preparation was achieved over an average time of 7.51 days for 65 patients and 10 days for 12 patients, and in only one case was not achieved. CONCLUSIONS: This experience suggests that negative pressure therapy may have an important role in wound bed preparation and as part of the treatment for wounds in the lower limbs of diabetic patients.

  6. Increase in vagal activity during hypotensive lower-body negative pressure in humans

    DEFF Research Database (Denmark)

    Sander-Jensen, K; Mehlsen, J; Stadeager, C

    1988-01-01

    Progressive central hypovolemia is characterized by a normotensive, tachycardic stage followed by a reversible, hypotensive stage with slowing of the heart rate (HR). We investigated circulatory changes and arterial hormone concentrations in response to lower-body negative pressure (LBNP) in six...... volunteers before and after atropine administration. LBNP of 55 mmHg initially resulted in an increase in HR from 55 +/- 4 to 90 +/- 5 beats/min and decreases in mean arterial pressure (MAP) from 94 +/- 4 to 81 +/- 5 mmHg, in central venous pressure from 7 +/- 1 to -3 +/- 1 mmHg, and in cardiac output from 6.......1 +/- 0.5 to 3.7 +/- 0.11/min. Concomitantly, epinephrine and norepinephrine levels increased. After 8.2 +/- 2.3 min of LBNP, the MAP had decreased to 41 +/- 7 mmHg and HR had decreased to 57 +/- 3 beats/min. Vasopressin increased from 1.2 +/- 0.3 to 137 +/- 45 pg/ml and renin activity increased from 1...

  7. Negative pressure driven phase transformation in Sr doped SmCoO₃.

    Science.gov (United States)

    Arshad Farhan, M; Javed Akhtar, M

    2010-02-24

    Atomistic computer simulation techniques based on energy minimization procedures are utilized for the structural investigation of perovskite-type SmCoO(3). A reliable potential model is derived which reproduces both cubic as well as orthorhombic phases of SmCoO(3). We observe a negative chemical pressure induced structural phase transformation from distorted perovskite (orthorhombic) to perfect perovskite (cubic) due to the substitution of Sr(2 + ) at the Sm(3 + ) sites. However, external hydrostatic pressure shows isotropic compression and no pressure-induced structural transformation is observed up to 100 GPa. To maintain the electroneutrality of the system, charge compensation is through oxygen vacancies which results in the brownmillerite-type structure. A defect model is proposed, which is consistent with experimental results. The solution energies for divalent and trivalent cations are also calculated. These results show that the cations having ionic radii less than 0.75 Å will occupy the Co sites and those with ionic radii larger than 0.75 Å will substitute at the Sm sites.

  8. Negative pressure wound therapy versus standard wound care on quality of life: a systematic review.

    Science.gov (United States)

    Janssen, A H J; Mommers, E H H; Notter, J; de Vries Reilingh, T S; Wegdam, J A

    2016-03-01

    Negative pressure wound therapy (NPWT) is a widely accepted treatment modality for open or infected wounds. Premature ending of NPWT occasionally occurs due to negative effects on the quality of life (QoL), however, the actual impact on QoL is unknown. The aim of this review is to analyse the effect of NPWT versus standard wound care (SWC) on QoL when used for the treatment of open or infected wounds. A systematic literature search in a range of databases (PubMed, CINAHL, Medline, Web of Science, Science Direct Freedom Collection, SwetsWise, PSYCArticles and Infrotrac Custom Journals) using the following search terms; 'standard wound care', 'wound dressing', 'dressing', 'treatment', OR 'negative pressure wound therapy [MESH]', OR 'vacuum assisted closure' AND 'quality of life [MESH]', 'patient-satisfaction', OR 'experiences' was performed. Methodological quality was assessed using the methodological index for non-randomised studies (MINORS) checklist. There were 42 studies identified, five matched the inclusion criteria: two randomised clinical trials (RCTs), one clinical comparative study, one exploratory prospective cohort study and one quasi experimental pilot study. Median MINORS-score was 75% (58%-96%). There were seven different questionnaires used to measure QoL or a subsidiary outcome. QoL in the NPWT group was lower in the first week, though no difference in QoL was observed thereafter. This systematic review observed that QoL improved at the end of therapy independent of which therapy was used. NPWT led to a lower QoL during the first week of treatment, possible due to aniexty, after which a similar or better QoL was reported when compared with SWC. It could be suggested that NPWT might be associated with increased anxiety. All authors of this publication have received no financial support or have personal interests conflicting with the objectivity of this manuscript.

  9. A comparison of VO2max and metabolic variables between treadmill running and treadmill skating.

    Science.gov (United States)

    Koepp, Kriston K; Janot, Jeffrey M

    2008-03-01

    The purpose of this study was to determine differences in VO2max and metabolic variables between treadmill running and treadmill skating. This study also examined VO2max responses during a continuous skating treadmill protocol and a discontinuous skating treadmill protocol. Sixteen male high school hockey players, who had a mean age of 16 +/- 1 years and were of an above-average fitness level, participated in this study. All subjects completed 4 exercise trials: a 1-hour skating treadmill familiarization trial, a treadmill running trial, and 2 randomized skating treadmill trials. Minute ventilation (VE), oxygen consumption VO2), carbon dioxide production VCO2), respiratory exchange ratio (RER), and heart rate were averaged every 15 seconds up to VO2max for each exercise test. The results showed that there was a significant difference (P skating treadmill protocol. There was also a significant difference for maximal RER between the discontinuous and continuous skating treadmill protocol and between the discontinuous skating treadmill protocol and running treadmill protocol. In conclusion, the running treadmill elicited a greater VO2max (mL.kg.min) than the skating treadmill did, but when it comes to specificity of ice skating, the skating treadmill may be ideal. Also, there was no significant difference between the discontinuous and continuous skating treadmill protocols. Therefore, a continuous protocol is possible on the skating treadmill without compromising correct skating position and physiologic responses. However, the continuous skating treadmill protocol should undergo validation before other scientists, coaches, and strength and conditioning professionals can apply it correctly.

  10. Magnetosphere and ionosphere response to a positive-negative pulse pair of solar wind dynamic pressure

    Science.gov (United States)

    Tian, A.; Degeling, A. W.

    2017-12-01

    Simulations and observations had shown that single positive/negative solar wind dynamic pressure pulse would excite geomagnetic impulsive events along with ionosphere and/or magnetosphere vortices which are connected by field aligned currents(FACs). In this work, a large scale ( 9min) magnetic hole event in solar wind provided us with the opportunity to study the effects of positive-negative pulse pair (△p/p 1) on the magnetosphere and ionosphere. During the magnetic hole event, two traveling convection vortices (TCVs, anti-sunward) first in anticlockwise then in clockwise rotation were detected by geomagnetic stations located along the 10:30MLT meridian. At the same time, another pair of ionospheric vortices azimuthally seen up to 3 MLT first in clockwise then in counter-clockwise rotation were also appeared in the afternoon sector( 14MLT) and centered at 75 MLAT without obvious tailward propagation feature. The duskside vortices were also confirmed in SuperDARN radar data. We simulated the process of magnetosphere struck by a positive-negative pulse pair and it shows that a pair of reversed flow vortices in the magnetosphere equatorial plane appeared which may provide FACs for the vortices observed in ionosphere. Dawn dusk asymmetry of the vortices as well as the global geomagnetism perturbation characteristics were also discussed.

  11. Supine exercise during lower body negative pressure effectively simulates upright exercise in normal gravity

    Science.gov (United States)

    Murthy, G.; Watenpaugh, D. E.; Ballard, R. E.; Hargens, A. R.

    1994-01-01

    Exercise within a lower body negative pressure (LBNP) chamber in supine posture was compared with similar exercise against Earth's gravity (without LBNP) in upright posture in nine healthy male volunteers. We measured footward force with a force plate, pressure in soleus and tibialis anterior muscles of the leg with transducer-tipped catheters, calf volume by strain gauge plethysmography, heart rate, and systolic and diastolic blood pressures during two conditions: 1) exercise in supine posture within an LBNP chamber during 100-mmHg LBNP (exercise-LBNP) and 2) exercise in upright posture against Earth's gravity without LBNP (exercise-1 G). Subjects exercised their ankle joints (dorsi- and plantarflexions) for 5 min during exercise-LBNP and for 5 min during exercise-1 G. Mean footward force produced during exercise-LBNP (743 +/- 37 N) was similar to that produced during exercise-1 G (701 +/- 24 N). Peak contraction pressure in the antigravity soleus muscle during exercise-LBNP (115 +/- 10 mmHg) was also similar to that during exercise-1 G (103 +/- 13 mmHg). Calf volume increased significantly by 3.3 +/- 0.5% during exercise-LBNP compared with baseline values. Calf volume did not increase significantly during exercise-1 G. Heart rate was significantly higher during exercise-LBNP (99 +/- 5 beats/min) than during exercise-1 G (81 +/- 3 beats/min). These results indicate that exercise in supine posture within an LBNP chamber can produce similar musculoskeletal stress in the legs and greater systemic cardiovascular stress than exercise in the upright posture against Earth's gravity.

  12. The effects of superimposed tilt and lower body negative pressure on anterior and posterior cerebral circulations.

    Science.gov (United States)

    Tymko, Michael M; Rickards, Caroline A; Skow, Rachel J; Ingram-Cotton, Nathan C; Howatt, Michael K; Day, Trevor A

    2016-09-01

    Steady-state tilt has no effect on cerebrovascular reactivity to increases in the partial pressure of end-tidal carbon dioxide (PETCO2). However, the anterior and posterior cerebral circulations may respond differently to a variety of stimuli that alter central blood volume, including lower body negative pressure (LBNP). Little is known about the superimposed effects of head-up tilt (HUT; decreased central blood volume and intracranial pressure) and head-down tilt (HDT; increased central blood volume and intracranial pressure), and LBNP on cerebral blood flow (CBF) responses. We hypothesized that (a) cerebral blood velocity (CBV; an index of CBF) responses during LBNP would not change with HUT and HDT, and (b) CBV in the anterior cerebral circulation would decrease to a greater extent compared to posterior CBV during LBNP when controlling PETCO2 In 13 male participants, we measured CBV in the anterior (middle cerebral artery, MCAv) and posterior (posterior cerebral artery, PCAv) cerebral circulations using transcranial Doppler ultrasound during LBNP stress (-50 mmHg) in three body positions (45°HUT, supine, 45°HDT). PETCO2 was measured continuously and maintained at constant levels during LBNP through coached breathing. Our main findings were that (a) steady-state tilt had no effect on CBV responses during LBNP in both the MCA (P = 0.077) and PCA (P = 0.583), and (b) despite controlling for PETCO2, both the MCAv and PCAv decreased by the same magnitude during LBNP in HUT (P = 0.348), supine (P = 0.694), and HDT (P = 0.407). Here, we demonstrate that there are no differences in anterior and posterior circulations in response to LBNP in different body positions. © 2016 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

  13. Cardiovascular response to lower body negative pressure stimulation before, during, and after space flight

    Science.gov (United States)

    Baisch, F.; Beck, L.; Blomqvist, G.; Wolfram, G.; Drescher, J.; Rome, J. L.; Drummer, C.

    2000-01-01

    BACKGROUND: It is well known that space travel cause post-flight orthostatic hypotension and it was assumed that autonomic cardiovascular control deteriorates in space. Lower body negative pressure (LBNP) was used to assess autonomic function of the cardiovascular system. METHODS: LBNP tests were performed on six crew-members before and on the first days post-flight in a series of three space missions. Additionally, two of the subjects performed LBNP tests in-flight. LBNP mimics fluid distribution of upright posture in a gravity independent way. It causes an artificial sequestration of blood, reduces preload, and filtrates plasma into the lower part of the body. Fluid distribution was assessed by bioelectrical impedance and anthropometric measurements. RESULTS: Heart rate, blood pressure, and total peripheral resistance increased significantly during LBNP experiments in-flight. The decrease in stroke volume, the increased pooling of blood, and the increased filtration of plasma into the lower limbs during LBNP indicated that a plasma volume reduction and a deficit of the interstitial volume of lower limbs rather than a change in cardiovascular control was responsible for the in-flight response. Post-flight LBNP showed no signs of cardiovascular deterioration. The still more pronounced haemodynamic changes during LBNP reflected the expected behaviour of cardiovascular control faced with less intravascular volume. In-flight, the status of an intra-and extravascular fluid deficit increases sympathetic activity, the release of vasoactive substances and consequently blood pressure. Post-flight, blood pressure decreases significantly below pre-flight values after restoration of volume deficits. CONCLUSION: We conclude that the cardiovascular changes in-flight are a consequence of a fluid deficit rather than a consequence of changes in autonomic signal processing.

  14. Validation of lower body negative pressure as an experimental model of hemorrhage

    Science.gov (United States)

    Shade, Robert E.; Muniz, Gary W.; Bauer, Cassondra; Goei, Kathleen A.; Pidcoke, Heather F.; Chung, Kevin K.; Cap, Andrew P.; Convertino, Victor A.

    2013-01-01

    Lower body negative pressure (LBNP), a model of hemorrhage (Hem), shifts blood to the legs and elicits central hypovolemia. This study compared responses to LBNP and actual Hem in sedated baboons. Arterial pressure, pulse pressure (PP), central venous pressure (CVP), heart rate, stroke volume (SV), and +dP/dt were measured. Hem steps were 6.25%, 12.5%, 18.75%, and 25% of total estimated blood volume. Shed blood was returned, and 4 wk after Hem, the same animals were subjected to four LBNP levels which elicited equivalent changes in PP and CVP observed during Hem. Blood gases, hematocrit (Hct), hemoglobin (Hb), plasma renin activity (PRA), vasopressin (AVP), epinephrine (EPI), and norepinephrine (NE) were measured at baseline and maximum Hem or LBNP. LBNP levels matched with 6.25%, 12.5%, 18.75%, and 25% hemorrhage were −22 ± 6, −41 ± 7, −54 ± 10, and −71 ± 7 mmHg, respectively (mean ± SD). Hemodynamic responses to Hem and LBNP were similar. SV decreased linearly such that 25% Hem and matching LBNP caused a 50% reduction in SV. Hem caused a decrease in Hct, Hb, and central venous oxygen saturation (ScvO2). In contrast, LBNP increased Hct and Hb, while ScvO2 remained unchanged. Hem caused greater elevations in AVP and NE than LBNP, while PRA, EPI, and other hematologic indexes did not differ between studies. These results indicate that while LBNP does not elicit the same effect on blood cell loss as Hem, LBNP mimics the integrative cardiovascular response to Hem, and validates the use of LBNP as an experimental model of central hypovolemia associated with Hem. PMID:24356525

  15. Diabetic foot wounds: the value of negative pressure wound therapy with instillation.

    Science.gov (United States)

    Dalla Paola, Luca

    2013-12-01

    Chronic wounds such as diabetic foot wounds are a tremendous burden to the health care system and often require a multidisciplinary approach to prevent amputations. Advanced technologies such as negative pressure wound therapy (NPWT) and bioengineered tissues have been successfully used in the treatment of these types of complex wounds. However, the introduction of NPWT with instillation (NPWTi) has provided an alternative treatment for treating complex and difficult-to-heal wounds. This article provides an overview of NPWT and the new NPWTi system and describes preliminary experience using NPWTi on patients with complicated infected diabetic foot wounds after surgical debridement and in a multidisciplinary setting. © 2013 The Author. International Wound Journal © 2013 John Wiley & Sons Ltd and Medicalhelplines.com Inc.

  16. Electrical admittance for filling of the heart during lower body negative pressure in humans

    DEFF Research Database (Denmark)

    Cai, Yujia; Holm, S; Jenstrup, M

    2000-01-01

    To evaluate whether electrical admittance of intracellular water is applicable for monitoring filling of the heart, we determined the difference in intracellular water in the thorax (Thorax(ICW)), measured as the reciprocal value of the electrical impedance for the thorax at 1.5 and 100 kHz during...... lower body negative pressure (LBNP) in humans. Changes in Thorax(ICW) were compared with positron emission tomography-determined C(15)O-labeled erythrocytes over the heart. During -40 mmHg LBNP, the blood volume of the heart decreased by 21 +/- 3% as the erythrocyte volume was reduced by 20 +/- 2.......6 to 40.9 +/- 5.0 S. 10(-4); P = 0.08). The correlation between Thorax(ICW) and heart erythrocyte volume was 0.84 (P electrical admittance of intracellular water can be applied to evaluate changes in blood volume of the heart during LBNP in humans....

  17. Negative pressure pulmonary oedema following use of ProSeal LMA

    Directory of Open Access Journals (Sweden)

    Richa Jain

    2013-01-01

    Full Text Available Negative pressure pulmonary oedema (NPPO is a life threatening condition, manifested due to upper airway obstruction in a spontaneously breathing patient. Upper airway obstruction caused by classic laryngeal mask airway (cLMA and ProSeal laryngeal mask airway (PLMA has been reported, and NPPO has also been reported following the use of cLMA. Search of literature did not confirm NPPO following the use of PLMA. We encountered a female patient of NPPO scheduled for incision and drainage of an abscess who had signs of airway obstruction following PLMA insertion. Multiple attempts were made to get patent airway without success. PLMA was replaced with endotracheal tube following which pink frothy secretion appeared in breathing circuit. Patient was managed successfully with ICU care.

  18. Negative ion molecule reactions of WF6: evidence for a pressure dependent branching ratio

    International Nuclear Information System (INIS)

    Viggiano, A.A.; Paulson, J.F.

    1984-01-01

    Rate coefficients have been measured in a selected ion flow tube (SIFT) for reactions of several negative ions with WF 6 . With the exception of SF - 5 , all the reactant ions studied having an electron detachment energy less than 3.36 eV reacted rapidly by charge exchange. SF - 5 transferred a fluoride ion producing WF - 7 . Ions with detachment energies greater than 3.36 eV associated rapidly with WF - 6 . Br - , with a detachment energy of 3.36 eV, reacted with WF 6 both by ion-neutral association and by charge exchange. The branching ratio for these two channels was found to depend on temperature and pressure. All these data indicate that the electron affinity of WF 6 is nearly equal to that of Br

  19. Negative-Pressure Cavitation Extraction of Secoisolariciresinol Diglycoside from Flaxseed Cakes

    Directory of Open Access Journals (Sweden)

    Hao Tian

    2015-06-01

    Full Text Available The negative-pressure cavitation extraction (NPCE technique was applied firstly to extract secoisolariciresinol diglucoside (SDG from flaxseed cakes. The significant extraction parameters were screened by fractional factorial design (FFD. The optimal parameters were determined using the central composite design (CCD with the two variables, NaOH amount and the liquid/solid ratio. The conditions of the extraction were optimized by using response surface methodology (RSM. Under the optimal conditions, the extraction yield and the extraction purity of SDG was 16.25 mg/g and 3.86%, respectively. The efficiency of NPCE was compared with that of conventional extraction methods. Our results demonstrated that NPCE was comparable to the well-known ultrasound-assisted extraction in term of extraction yield and purity. This extraction technique has advantages of less time-consuming, low solvent usage and high throughput capability.

  20. Negative pressure wound therapy in pediatric surgery: How and when to use.

    Science.gov (United States)

    de Jesus, Lisieux Eyer; Martins, Alana Bandeira; Oliveira, Pablo Baptista; Gomes, Fernanda; Leve, Thais; Dekermacher, Samuel

    2018-04-01

    Negative pressure wound therapy (NPWT) has been widely adopted to treat laparostomy, abdominal compartment syndrome (ACS) and complicated wounds associated with tissue loss. The method presents specific aspects, advantages and indications in Pediatrics. Our aim is to review the evidence available about NPWT in children. Active search for papers about NPWT in Pediatric patients. Papers referring to orthopedic problems, wound complications after Cardiac Surgery or burns were excluded. The method shows good results to treat ACS, complicated wounds and abdominal wall malformations in neonates, including prematures. Periwound skin protection, monitoring of fluid losses and fine tuning of negative pressure levels according to age are necessary. Less pain, quicker recovery, less frequent dressing changes, possible recovery of exposed surgical hardware, granulation and shrinkage of the wound are advantages of the method over other kinds of dressing. NPWT is contraindicated over blood vessels and exposed nerves. Debridement is needed before usage over necrotic areas. Enteric fistulae are not contraindications. Complications are rare, mainly foam retention and dermatitis/skin maceration. The possibility of fistulae being caused by NPWT remains debatable. NPWT is widely used in Pediatrics, including neonates and premature, but the evidence available about the method is scarce and low quality. Complications are uncommon and mostly manageable. A possible causal relationship between NPWY and enteric fistula remains unclear. Adult devices and parameters have been adapted to children's use. Extra care is needed to protect the delicate tissues of Pediatric patients. Comparative research to define differential costs, indications and advantages of the method, specific indications and limits of NWTP in Pediatrics is needed. Review. IV. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Intrarectal negative pressure system in the management of open abdomen with colorectal fistula: A case report☆

    Science.gov (United States)

    Yetişir, Fahri; Salman, A. Ebru; Mamedov, Ruslan; Aksoy, Mustafa; Yalcin, Abdussamet; Kayaalp, Cüneyt

    2014-01-01

    INTRODUCTION To present the management of open abdomen with colorectal fistula by application of intrarectal negative pressure system (NPS) in addition to abdominal NPS. PRESENTATION OF CASE Twenty-year old man had a history of injuries by a close-range gunshot to the abdomen eight days ago and he had been treated by bowel repairs, resections, jejunal anastomosis and Hartman's procedure. He was referred to our center after deterioration, evisceration with open abdomen and enteric fistula in septic shock. There were edematous, fibrinous bowels and large multiple fistulas from the edematous rectal stump. APACHE II, Mannheim Peritoneal Index and Björck scores were 18, 33 and 3, respectively (expected mortality 100%). After intensive care for 5 days, he was treated by abdominal and intrarectal NPS. NPS repeated for 5 times and the fistula was recovered on day 18 completely. Fascial closure was facilitated with a dynamic abdominal closure system (ABRA) and he was discharged on day 33 uneventfully. There was no herniation and any other problem after 12 months follow-up. DISCUSSION Management of fistula in OA can be extremely challenging. Floating stoma, fistula VAC, nipple VAC, ring and silo VAC, fistula intubation systems are used for isolation of the enteric effluent from OA. Several biologic dressings such as acellular dermal matrix, pedicled flaps have been used to seal the fistula opening with various success. Resection of the involved enteric loop and a new anastomosis of the intestine is very hard and rarely possible. In all of these reports, usually patients are left to heal with a giant hernia. In contrast to this, there is no hernia in our case during one year follow up period. CONCLUSION Combination of intra and extra luminal negative pressure systems and ABRA is a safe and successful method to manage open abdomen with colorectal fistula. PMID:24584042

  2. Intrarectal negative pressure system in the management of open abdomen with colorectal fistula: A case report.

    Science.gov (United States)

    Yetişir, Fahri; Salman, A Ebru; Mamedov, Ruslan; Aksoy, Mustafa; Yalcin, Abdussamet; Kayaalp, Cüneyt

    2014-01-01

    To present the management of open abdomen with colorectal fistula by application of intrarectal negative pressure system (NPS) in addition to abdominal NPS. Twenty-year old man had a history of injuries by a close-range gunshot to the abdomen eight days ago and he had been treated by bowel repairs, resections, jejunal anastomosis and Hartman's procedure. He was referred to our center after deterioration, evisceration with open abdomen and enteric fistula in septic shock. There were edematous, fibrinous bowels and large multiple fistulas from the edematous rectal stump. APACHE II, Mannheim Peritoneal Index and Björck scores were 18, 33 and 3, respectively (expected mortality 100%). After intensive care for 5 days, he was treated by abdominal and intrarectal NPS. NPS repeated for 5 times and the fistula was recovered on day 18 completely. Fascial closure was facilitated with a dynamic abdominal closure system (ABRA) and he was discharged on day 33 uneventfully. There was no herniation and any other problem after 12 months follow-up. Management of fistula in OA can be extremely challenging. Floating stoma, fistula VAC, nipple VAC, ring and silo VAC, fistula intubation systems are used for isolation of the enteric effluent from OA. Several biologic dressings such as acellular dermal matrix, pedicled flaps have been used to seal the fistula opening with various success. Resection of the involved enteric loop and a new anastomosis of the intestine is very hard and rarely possible. In all of these reports, usually patients are left to heal with a giant hernia. In contrast to this, there is no hernia in our case during one year follow up period. Combination of intra and extra luminal negative pressure systems and ABRA is a safe and successful method to manage open abdomen with colorectal fistula. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  3. Comparison of compensatory reserve during lower-body negative pressure and hemorrhage in nonhuman primates.

    Science.gov (United States)

    Hinojosa-Laborde, Carmen; Howard, Jeffrey T; Mulligan, Jane; Grudic, Greg Z; Convertino, Victor A

    2016-06-01

    Compensatory reserve was measured in baboons (n = 13) during hemorrhage (Hem) and lower-body negative pressure (LBNP) using a machine-learning algorithm developed to estimate compensatory reserve by detecting reductions in central blood volume during LBNP. The algorithm calculates compensatory reserve index (CRI) from normovolemia (CRI = 1) to cardiovascular decompensation (CRI = 0). The hypothesis was that Hem and LBNP will elicit similar CRI values and that CRI would have higher specificity than stroke volume (SV) in predicting decompensation. Blood was removed in four steps: 6.25%, 12.5%, 18.75%, and 25% of total blood volume. Four weeks after Hem, the same animals were subjected to four levels of LBNP that was matched on the basis of their central venous pressure. Data (mean ± 95% confidence interval) indicate that CRI decreased (P AUC in Hem (0.94 vs. 0.84) and LBNP (0.94 vs. 0.92). These data support the hypothesis that Hem and LBNP elicited the same CRI response, suggesting that measurement of compensatory reserve is superior to SV as a predictor of cardiovascular decompensation.

  4. Development of micropump-actuated negative pressure pinched injection for parallel electrophoresis on array microfluidic chip.

    Science.gov (United States)

    Li, Bowei; Jiang, Lei; Xie, Hua; Gao, Yan; Qin, Jianhua; Lin, Bingcheng

    2009-09-01

    A micropump-actuated negative pressure pinched injection method is developed for parallel electrophoresis on a multi-channel LIF detection system. The system has a home-made device that could individually control 16-port solenoid valves and a high-voltage power supply. The laser beam is excitated and distributes to the array separation channels for detection. The hybrid Glass-PDMS microfluidic chip comprises two common reservoirs, four separation channels coupled to their respective pneumatic micropumps and two reference channels. Due to use of pressure as a driving force, the proposed method has no sample bias effect for separation. There is only one high-voltage supply needed for separation without relying on the number of channels, which is significant for high-throughput analysis, and the time for sample loading is shortened to 1 s. In addition, the integrated micropumps can provide the versatile interface for coupling with other function units to satisfy the complicated demands. The performance is verified by separation of DNA marker and Hepatitis B virus DNA samples. And this method is also expected to show the potential throughput for the DNA analysis in the field of disease diagnosis.

  5. Tolerance of Lower Body Negative Pressure (LBNP) in endurance runners, weightlifters, swimmers and nonathletes

    Science.gov (United States)

    1980-01-01

    Thirteen endurance runners (R), 12 weightlifters (WL), 12 swimmers (SW) and 10 nonathletes (NA) were tested for their tolerance of lower body negative pressure (LBNP) in consecutive 5 minute stages at -20, -30, -40, -50 and -60 torr. Each subject also performed an exercise test on a bicycle ergometer with progressive workloads to exhaustion to determined aerobic capacity. The R had a much higher aerobic capacity than any of the other groups, but a significantly lower LBNP tolerance. While responses in heart rate and pulse pressure were quite similar in all 4 groups, the rate of increase in leg volume relative to LBNP stress (leg compliance, LC) was considerably greater in R than in the other athletes and NA. The greater LC in R could be attributed not only to a more rapid shift of blood to the lower extremities but also to a greater tendency for edema formation, both contributing to a more rapid loss in effective central blood volume for a given LBNP stress. These results substantiate earlier observations which led to the conclusion that endurance running is not advisable as a training regimen for astronauts.

  6. Skin graft fixation in severe burns: use of topical negative pressure.

    Science.gov (United States)

    Kamolz, L P; Lumenta, D B; Parvizi, D; Wiedner, M; Justich, I; Keck, M; Pfurtscheller, K; Schintler, M

    2014-09-30

    Over the last 50 years, the evolution of burn care has led to a significant decrease in mortality. The biggest impact on survival has been the change in the approach to burn surgery. Early excision and grafting has become a standard of care for the majority of patients with deep burns; the survival of a given patient suffering from major burns is invariably linked to the take rate and survival of skin grafts. The application of topical negative pressure (TNP) therapy devices has demonstrated improved graft take in comparison to conventional dressing methods alone. The aim of this study was to analyze the impact of TNP therapy on skin graft fixation in large burns. In all patients, we applied TNP dressings covering a %TBSA of >25. The following parameters were recorded and documented using BurnCase 3D: age, gender, %TBSA, burn depth, hospital length-of-stay, Baux score, survival, as well as duration and incidence of TNP dressings. After a burn depth adapted wound debridement, coverage was simultaneously performed using split-thickness skin grafts, which were fixed with staples and covered with fatty gauzes and TNP foam. The TNP foam was again fixed with staples to prevent displacement and finally covered with the supplied transparent adhesive film. A continuous subatmospheric pressure between 75-120 mm Hg was applied (VAC®, KCI, Vienna, Austria). The first dressing change was performed on day 4. Thirty-six out of 37 patients, suffering from full thickness burns, were discharged with complete wound closure; only one patient succumbed to their injuries. The overall skin graft take rate was over 95%. In conclusion, we consider that split thickness skin graft fixation by TNP is an efficient method in major burns, notably in areas with irregular wound surfaces or subject to movement (e.g. joint proximity), and is worth considering for the treatment of aged patients.

  7. Comparison of compensatory reserve during lower-body negative pressure and hemorrhage in nonhuman primates

    Science.gov (United States)

    Howard, Jeffrey T.; Mulligan, Jane; Grudic, Greg Z.; Convertino, Victor A.

    2016-01-01

    Compensatory reserve was measured in baboons (n = 13) during hemorrhage (Hem) and lower-body negative pressure (LBNP) using a machine-learning algorithm developed to estimate compensatory reserve by detecting reductions in central blood volume during LBNP. The algorithm calculates compensatory reserve index (CRI) from normovolemia (CRI = 1) to cardiovascular decompensation (CRI = 0). The hypothesis was that Hem and LBNP will elicit similar CRI values and that CRI would have higher specificity than stroke volume (SV) in predicting decompensation. Blood was removed in four steps: 6.25%, 12.5%, 18.75%, and 25% of total blood volume. Four weeks after Hem, the same animals were subjected to four levels of LBNP that was matched on the basis of their central venous pressure. Data (mean ± 95% confidence interval) indicate that CRI decreased (P < 0.001) from baseline during Hem (0.69 ± 0.10, 0.57 ± 0.09, 0.36 ± 0.10, 0.16 ± 0.08, and 0.08 ± 0.03) and LBNP (0.76 ± 0.05, 0.66 ± 0.08, 0.36 ± 0.13, 0.23 ± 0.11, and 0.14 ± 0.09). CRI was not different between Hem and LBNP (P = 0.20). Linear regression analysis between Hem CRI and LBNP CRI revealed a slope of 1.03 and a correlation coefficient of 0.96. CRI exhibited greater specificity than SV in both Hem (92.3 vs. 82.1) and LBNP (94.8 vs. 83.1) and greater ROC AUC in Hem (0.94 vs. 0.84) and LBNP (0.94 vs. 0.92). These data support the hypothesis that Hem and LBNP elicited the same CRI response, suggesting that measurement of compensatory reserve is superior to SV as a predictor of cardiovascular decompensation PMID:27030667

  8. Cost study of dermal substitutes and topical negative pressure in the surgical treatment of burns.

    Science.gov (United States)

    Hop, M Jenda; Bloemen, Monica C T; van Baar, Margriet E; Nieuwenhuis, Marianne K; van Zuijlen, Paul P M; Polinder, Suzanne; Middelkoop, Esther

    2014-05-01

    A recently performed randomised controlled trial investigated the clinical effectiveness of dermal substitutes (DS) and split skin grafts (SSG) in combination with topical negative pressure (TNP) in the surgical treatment of burn wounds. In the current study, medical and non-medical costs were investigated, to comprehensively assess the benefits of this new treatment. The primary outcome was mean total costs of the four treatment strategies: SSG with or without DS, and with or without TNP. Costs were studied from a societal perspective. Findings were evaluated in light of the clinical effects on scar elasticity. Eighty-six patients were included. Twelve months post-operatively, highest elasticity was measured in scars treated with DS and TNP (p=0.027). The initial cost price of treatment with DS and TNP was €2912 compared to treatment with SSG alone €1703 (ptreatment contributed maximal 7% to the total costs and total costs varied widely within and between groups, but were not significantly different. Therefore, in the selection of the most optimal type of surgical intervention, cost considerations should not play an important role. Copyright © 2013 Elsevier Ltd and ISBI. All rights reserved.

  9. Evidence for negative effects of elevated intra-abdominal pressure on pulmonary mechanics and oxidative stress.

    Science.gov (United States)

    Davarcı, I; Karcıoğlu, M; Tuzcu, K; İnanoğlu, K; Yetim, T D; Motor, S; Ulutaş, K T; Yüksel, R

    2015-01-01

    To compare the effects of pneumoperitoneum on lung mechanics, end-tidal CO2 (ETCO2), arterial blood gases (ABG), and oxidative stress markers in blood and bronchoalveolar lavage fluid (BALF) during laparoscopic cholecystectomy (LC) by using lung-protective ventilation strategy. Forty-six patients undergoing LC and abdominal wall hernia (AWH) surgery were assigned into 2 groups. Measurements and blood samples were obtained before, during pneumoperitoneum, and at the end of surgery. BALF samples were obtained after anesthesia induction and at the end of surgery. Peak inspiratory pressure, ETCO2, and pCO2 values at the 30th minute were significantly increased, while there was a significant decrease in dynamic lung compliance, pH, and pO2 values in LC group. In BALF samples, total oxidant status (TOS), arylesterase, paraoxonase, and malondialdehyde levels were significantly increased; the glutathione peroxidase levels were significantly decreased in LC group. The serum levels of TOS and paraoxonase were significantly higher at the end of surgery in LC group. In addition, arylesterase level in the 30th minute was increased compared to baseline. Serum paraoxonase level at the end of surgery was significantly increased when compared to AWH group. Our study showed negative effects of pneumoperitoneum in both lung and systemic levels despite lung-protective ventilation strategy.

  10. Evidence for Negative Effects of Elevated Intra-Abdominal Pressure on Pulmonary Mechanics and Oxidative Stress

    Directory of Open Access Journals (Sweden)

    I. Davarcı

    2015-01-01

    Full Text Available Objective. To compare the effects of pneumoperitoneum on lung mechanics, end-tidal CO2 (ETCO2, arterial blood gases (ABG, and oxidative stress markers in blood and bronchoalveolar lavage fluid (BALF during laparoscopic cholecystectomy (LC by using lung-protective ventilation strategy. Materials and Methods. Forty-six patients undergoing LC and abdominal wall hernia (AWH surgery were assigned into 2 groups. Measurements and blood samples were obtained before, during pneumoperitoneum, and at the end of surgery. BALF samples were obtained after anesthesia induction and at the end of surgery. Results. Peak inspiratory pressure, ETCO2, and pCO2 values at the 30th minute were significantly increased, while there was a significant decrease in dynamic lung compliance, pH, and pO2 values in LC group. In BALF samples, total oxidant status (TOS, arylesterase, paraoxonase, and malondialdehyde levels were significantly increased; the glutathione peroxidase levels were significantly decreased in LC group. The serum levels of TOS and paraoxonase were significantly higher at the end of surgery in LC group. In addition, arylesterase level in the 30th minute was increased compared to baseline. Serum paraoxonase level at the end of surgery was significantly increased when compared to AWH group. Conclusions. Our study showed negative effects of pneumoperitoneum in both lung and systemic levels despite lung-protective ventilation strategy.

  11. Use of a risk assessment method to improve the safety of negative pressure wound therapy.

    Science.gov (United States)

    Lelong, Anne-Sophie; Martelli, Nicolas; Bonan, Brigitte; Prognon, Patrice; Pineau, Judith

    2014-06-01

    To conduct a risk analysis of the negative pressure wound therapy (NPWT) care process and to improve the safety of NPWT, a working group of nurses, hospital pharmacists, physicians and hospital managers performed a risk analysis for the process of NPWT care. The failure modes, effects and criticality analysis (FMECA) method was used for this analysis. Failure modes and their consequences were defined and classified as a function of their criticality to identify priority actions for improvement. By contrast to classical FMECA, the criticality index (CI) of each consequence was calculated by multiplying occurrence, severity and detection scores. We identified 13 failure modes, leading to 20 different consequences. The CI of consequences was initially 712, falling to 357 after corrective measures were implemented. The major improvements proposed included the establishment of 6-monthly training cycles for nurses, physicians and surgeons and the introduction of computerised prescription for NPWT. The FMECA method also made it possible to prioritise actions as a function of the criticality ranking of consequences and was easily understood and used by the working group. This study is, to our knowledge, the first to use the FMECA method to improve the safety of NPWT. © 2012 The Authors. International Wound Journal © 2012 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

  12. The use of negative pressure wound therapy in the treatment of infected wounds. Case studies

    Directory of Open Access Journals (Sweden)

    Daniel de Alcântara Jones

    Full Text Available ABSTRACT OBJECTIVE: To evaluate the results and benefits obtained from the topical use of negative pressure wound therapy (NPWT in patients with infected wounds. METHODS: This was a retrospective study of 20 patients (17 males and three females, mean age 42 years with infected wounds treated using NPWT. The infected wounds were caused by trauma. The treatment system used was VAC.(r (Vacuum Assisted Closure, KCI, San Antonio, United States applied to the wound in continuous mode from 100 to 125 mmHg. The parameters related to the wounds (location, number of VAC changes, the size of the defects in the soft parts, and the evolution of the state of the wound, length of hospital stay, length of intravenous antibiotic therapy, and complications related to the use of this therapy were evaluated. RESULTS: The mean length of the hospital stay, use of NPWT, and antibacterial therapy were 41 days, 22.5 days, and 20 days respectively. The use of the VAC led to a mean reduction of 29% in the wound area (95.65-68.1 cm2; p < 0.05. Only one patient did not show any improvement in the final appearance of the wound with complete eradication of the infection. No complication directly caused by NPWT was observed. CONCLUSION: NPWT stimulates infection-free scar tissue formation in a short time, and is a quick and comfortable alternative to conventional infected wounds treatment methods.

  13. Takotsubo cardiomyopathy precipitated by negative pressure pulmonary oedema following total thyroidectomy

    Directory of Open Access Journals (Sweden)

    K S Bharathi

    2016-01-01

    Full Text Available 'Takotsubo cardiomyopathy (TCM' or 'stress cardiomyopathy' is a reversible cardiomyopathy that is precipitated by intense emotional or physical stress. This syndrome is characterised by symptoms mimicking acute coronary syndrome with transient systolic dysfunction associated with regional wall motion abnormalities, which extend beyond a single coronary vascular bed in the absence of obstructive coronary vascular disease. The presentation of TCM and myocardial infarction is similar with sudden onset of chest pain, breathlessness as well as abnormalities in both the electrocardiogram and cardiac enzymes. It is difficult to differentiate between the two until cardiac catheterisation establishes the diagnosis. We report a case of TCM in a post-menopausal female, precipitated by negative pressure pulmonary oedema following total thyroidectomy in whom timely cardiac catheterisation established the diagnosis and influenced the management. Heightened awareness of this unique cardiomyopathy is essential to have a high index of suspicion in at-risk population for the prompt diagnosis of stress-related cardiomyopathy syndromes occurring in the perioperative period.

  14. Comparing negative pressure wound treatment with honey dressing in healing of foot ulcers in diabetics

    International Nuclear Information System (INIS)

    Bashir, U.; Maqsood, R.; Shabbir, H.

    2018-01-01

    To evaluate and compare the effectiveness of vacuum assisted treatment with that of honey dressing in duration of healing of foot ulcers in diabetics. Study Design: Randomized control study. Place and Duration of Study: Combined Military Hospital Multan and Nishtar Hospital Multan, from Aug 2016 till Feb 2017. Patients and Methods: A total of 95 patients with ages between 30-60 years of both sexes, who presented with diabetic ulcers of foot involving subcutaneous tissue and skin. Patients were divided randomly into two groups; Group V and H. Group V was subjected to Vacuum Pack closure (negative pressure wound treatment) and group H was treated with honey dressing, follow up was done till the appearance of healthy tissue after initial debridement, suitable for STSG (Split Thickness Skin Graft) or primary closure. Results: Healthy tissue appeared much faster in Vacuum assisted treatment, then with honey dressing with mean of 18.2 days for V.A.C and 28.8 days for honey dressing. Conclusion: Vacuum assisted closure was more effective in the treatment of foot ulcers in diabetics. It promotes healthy granulation tissue in the wound bed at a faster rate in comparison to honey dressing. (author)

  15. Effect of negative pressure wound therapy on molecular markers in diabetic foot ulcers.

    Science.gov (United States)

    Karam, Rehab A; Rezk, Noha A; Abdel Rahman, Tamer M; Al Saeed, Mohamed

    2018-08-15

    Diabetic foot ulcers are one of the most common complications of diabetes with high morbidity and mortality. Negative pressure wound therapy (NPWT) is one of the treatment modalities that facilitates the wound healing process; however, its molecular mechanism remains unclear. The aim of this study was to investigate the mechanism of action of NPWT in the treatment of diabetic foot ulcers via measuring the tissue expression of genes related to the wound healing process. The study included 40 patients with diabetic foot ulceration, 20 of them received NPWT and the other 20 were a control group treated with advanced moist therapy. Granulation tissue biopsies were obtained before and 10 days after treatment in both groups and subjected to real-time polymerase chain reaction to measure the mRNA expression of TGF-β1, VEGF, TNF-α, IL-1β, MMP-1, MMP-9 and TIMP-1 which are involved in the wound healing pathway. After 10 days of treatment with NPWT, the mRNA levels of IL-1β, TNF-α, MMP-1, and MMP-9 were significantly downregulated, while the levels of VEGF, TGF-β1 and TIMP-1 were significantly increased. Our study demonstrated that NPWT promotes wound healing in diabetic foot ulcers possibly by affecting growth factors, inflammatory cytokines, and matrix metalloproteinases. Copyright © 2018 Elsevier B.V. All rights reserved.

  16. Efficacy of Negative Pressure Wound Treatment in Preventing Surgical Site Infections after Whipple Procedures.

    Science.gov (United States)

    Gupta, Ryan; Darby, Geoffrey C; Imagawa, David K

    2017-10-01

    Surgical site infections (SSIs) occur at an average rate of 21.1 per cent after Whipple procedures per NSQIP data. In the setting of adherence to standard National Surgery Quality Improvement Program (NSQIP) Hepatopancreatobiliary recommendations including wound protector use and glove change before closing, this study seeks to evaluate the efficacy of using negative pressure wound treatment (NPWT) over closed incision sites after a Whipple procedure to prevent SSI formation. We retrospectively examined consecutive patients from January 2014 to July 2016 who met criteria of completing Whipple procedures with full primary incision closure performed by a single surgeon at a single institution. Sixty-one patients were included in the study between two cohorts: traditional dressing (TD) (n = 36) and NPWT dressing (n = 25). There was a statistically significant difference (P = 0.01) in SSI formation between the TD cohort (n = 15, SSI rate = 0.41) and the NPWT cohort (n = 3, SSI rate = 0.12). The adjusted odds ratio (OR) of SSI formation was significant for NPWT use [OR = 0.15, P = 0.036] and for hospital length of stay [OR = 1.21, P = 0.024]. Operative length, operative blood loss, units of perioperative blood transfusion, intraoperative gastrojejunal tube placement, preoperative stent placement, and postoperative antibiotic duration did not significantly impact SSI formation (P > 0.05).

  17. Improving balance skills in patients who had stroke through virtual reality treadmill training.

    Science.gov (United States)

    Yang, Saiwei; Hwang, Wei-Hsung; Tsai, Yi-Ching; Liu, Fu-Kang; Hsieh, Lin-Fen; Chern, Jen-Suh

    2011-12-01

    The aim of this study was to evaluate the effects of virtual reality (VR) treadmill training on the balance skills of patients who have had a stroke. A total of 14 patients with strokes were recruited and randomly assigned to receive VR treadmill or traditional treadmill training. The outcome measures that were included for the study were center of pressure (COP) sway excursion, COP maximum sway in anterior-posterior direction, COP maximum sway in medial-lateral direction, COP sway area, bilateral limb-loading symmetric index, the sway excursion values for the paretic foot (sway excursion/P), paretic limb stance time (stance time/P), number of steps of the paretic limb (number of steps/P), and contact area of the paretic foot (contact A/P) during quiet stance, sit-to-stand transfer, and level walking. There were no significant improvements in COP-related measures and symmetric index during the quiet stance, either in the VR treadmill or traditional treadmill training group (P > 0.05). However, the difference between groups after training in COP maximum sway in medial-lateral direction during the quiet stance was significant (P = 0.038). Traditional treadmill training failed to improve sit-to-stand performance, whereas VR treadmill training improved symmetric index (P = 0.028) and sway excursion (P = 0.046) significantly during sit-to-stand transfer. The changes of symmetric index between groups were markedly different (P = 0.045). Finally, both groups improved significantly in stance time/P, but only VR treadmill training increased contact A/P (P = 0.034) after training during level walking. The difference between groups during level walking was not significant. Neither traditional treadmill nor VR treadmill training had any effect on balance skill during quiet stance, but VR treadmill training improved balance skill in the medial-lateral direction better than traditional training did. VR treadmill training also improved balance skill during sit-to-stand transfers

  18. Oscillatory lower body negative pressure impairs working memory task-related functional hyperemia in healthy volunteers.

    Science.gov (United States)

    Merchant, Sana; Medow, Marvin S; Visintainer, Paul; Terilli, Courtney; Stewart, Julian M

    2017-04-01

    Neurovascular coupling (NVC) describes the link between an increase in task-related neural activity and increased cerebral blood flow denoted "functional hyperemia." We previously showed induced cerebral blood flow oscillations suppressed functional hyperemia; conversely functional hyperemia also suppressed cerebral blood flow oscillations. We used lower body negative pressure (OLBNP) oscillations to force oscillations in middle cerebral artery cerebral blood flow velocity (CBFv). Here, we used N-back testing, an intellectual memory challenge as a neural activation task, to test the hypothesis that OLBNP-induced oscillatory cerebral blood flow can reduce functional hyperemia and NVC produced by a working memory task and can interfere with working memory. We used OLBNP (-30 mmHg) at 0.03, 0.05, and 0.10 Hz and measured spectral power of CBFv at all frequencies. Neither OLBNP nor N-back, alone or combined, affected hemodynamic parameters. 2-Back power and OLBNP individually were compared with 2-back power during OLBNP. 2-Back alone produced a narrow band increase in oscillatory arterial pressure (OAP) and oscillatory cerebral blood flow power centered at 0.0083 Hz. Functional hyperemia in response to 2-back was reduced to near baseline and 2-back memory performance was decreased by 0.03-, 0.05-, and 0.10-Hz OLBNP. OLBNP alone produced increased oscillatory power at frequencies of oscillation not suppressed by added 2-back. However, 2-back preceding OLBNP suppressed OLBNP power. OLBNP-driven oscillatory CBFv blunts NVC and memory performance, while memory task reciprocally interfered with forced CBFv oscillations. This shows that induced cerebral blood flow oscillations suppress functional hyperemia and functional hyperemia suppresses cerebral blood flow oscillations. NEW & NOTEWORTHY We show that induced cerebral blood flow oscillations suppress functional hyperemia produced by a working memory task as well as memory task performance. We conclude that oscillatory

  19. Clinical Features of Patients with Diffuse Alveolar Hemorrhage due to Negative-Pressure Pulmonary Edema.

    Science.gov (United States)

    Contou, Damien; Voiriot, Guillaume; Djibré, Michel; Labbé, Vincent; Fartoukh, Muriel; Parrot, Antoine

    2017-08-01

    Diffuse alveolar hemorrhage (DAH) with negative-pressure pulmonary edema (NPPE) is an uncommon yet life-threatening condition. We aimed at describing the circumstances, clinical, radiological, and bronchoscopic features, as well as the outcome of patients with NPPE-related DAH. We performed a retrospective, observational cohort study, using data prospectively collected over 35 years in an intensive care unit (ICU). Of the 149 patients admitted for DAH, we identified 18 NPPE episodes in 15 patients, one admitted four times for recurrent NPPE-related DAH. The patients were primarily young, male, and athletic. The NPPE setting was postoperative (n = 12/18, 67%) or following generalized tonic-clonic seizures (n = 6/18, 33%). Hemoptysis was almost constant (n = 17/18, 94%), yet rarely massive (>200 cc, n = 1/18, 6%), with anemia observed in 10 (56%) episodes. The DAH triad (hemoptysis, anemia, and pulmonary infiltrates) was observed in 50% of episodes (n = 9/18), and acute respiratory failure in 94% (n = 17/18). Chest computed tomography revealed diffuse bilateral ground glass opacities (n = 10/10, 100%), while bronchoscopy detected bilateral hemorrhage (n = 12/12, 100%) and macroscopically bloody bronchoalveolar lavage, with siderophage absence in most (n = 7/8, 88%), indicating acute DAH. While one episode proved fatal, the other 17 recovered rapidly, with a mean ICU stay lasting 4.6 (2-15) days. Typically, the evolution was rapidly favorable under supportive care. NPPE-related DAH is a rare life-threatening condition occurring primarily after tonic-clonic generalized seizure or generalized anesthesia. Clinical circumstances are a key to its diagnosis. Early diagnosis and recognition likely allow for successful management of this potentially serious complication, whereas ictal-DAH appears ominous in epileptic patients.

  20. Negative pressure wound therapy after partial diabetic foot amputation: a multicentre, randomised controlled trial.

    Science.gov (United States)

    Armstrong, David G; Lavery, Lawrence A

    2005-11-12

    Diabetic foot wounds, particularly those secondary to amputation, are very complex and difficult to treat. We investigated whether negative pressure wound therapy (NPWT) improves the proportion and rate of wound healing after partial foot amputation in patients with diabetes. We enrolled 162 patients into a 16-week, 18-centre, randomised clinical trial in the USA. Inclusion criteria consisted of partial foot amputation wounds up to the transmetatarsal level and evidence of adequate perfusion. Patients who were randomly assigned to NPWT (n=77) received treatment with dressing changes every 48 h. Control patients (n=85) received standard moist wound care according to consensus guidelines. NPWT was delivered through the Vacuum Assisted Closure (VAC) Therapy System. Wounds were treated until healing or completion of the 112-day period of active treatment. Analysis was by intention to treat. This study has been registered with , number NCT00224796. More patients healed in the NPWT group than in the control group (43 [56%] vs 33 [39%], p=0.040). The rate of wound healing, based on the time to complete closure, was faster in the NPWT group than in controls (p=0.005). The rate of granulation tissue formation, based on the time to 76-100% formation in the wound bed, was faster in the NPWT group than in controls (p=0.002). The frequency and severity of adverse events (of which the most common was wound infection) were similar in both treatment groups. NPWT delivered by the VAC Therapy System seems to be a safe and effective treatment for complex diabetic foot wounds, and could lead to a higher proportion of healed wounds, faster healing rates, and potentially fewer re-amputations than standard care.

  1. A prospective randomized evaluation of negative-pressure wound dressings for diabetic foot wounds.

    Science.gov (United States)

    Eginton, Mark T; Brown, Kellie R; Seabrook, Gary R; Towne, Jonathan B; Cambria, Robert A

    2003-11-01

    Optimal treatment for large diabetic foot wounds is ill defined. The purpose of this study was to compare the rate of wound healing with the Vacuum Assisted Closure device trade mark (VAC) to conventional moist dressings in the treatment of large diabetic foot wounds. Diabetics with significant soft tissue defects of the foot were considered for enrollment. Patients were randomized to receive either moist gauze dressings or VAC treatments for 2 weeks, after which they were treated with the alternative dressing for an additional 2 weeks. Wounds were photographed weekly and wound dimensions calculated in a blinded fashion with spatial analysis software. Percent change in wound dimensions were calculated and compared for each weekly assessment and over 2 weeks of therapy with each dressing type. Ten patients were enrolled in the trial, but two were lost to follow-up and two were withdrawn. Complete data were available for analysis on seven wounds in six patients. Average length, width, and depth of the wounds at initiation of the trial was 7.7, 3.5, and 3.1 cm, respectively. Only the wound depth was significantly decreased over the weeks of the trial to 1.2 cm ( p VAC dressings decreased the wound volume and depth significantly more than moist gauze dressings (59% vs. 0% and 49% vs. 8%, respectively). VAC dressings were associated with a decrease in all wound dimensions while wound length and width increased with moist dressings. In summary, over the first several weeks of therapy, VAC dressings decreased wound depth and volume more effectively than moist gauze dressings. Negative-pressure wound treatment may accelerate closure of large foot wounds in the diabetic patient.

  2. Cost-Utility Analysis: Sartorius Flap versus Negative Pressure Therapy for Infected Vascular Groin Graft Managment.

    Science.gov (United States)

    Chatterjee, Abhishek; Macarios, David; Griffin, Leah; Kosowski, Tomasz; Pyfer, Bryan J; Offodile, Anaeze C; Driscoll, Daniel; Maddali, Sirish; Attwood, John

    2015-11-01

    Sartorius flap coverage and adjunctive negative pressure wound therapy (NPWT) have been described in managing infected vascular groin grafts with varying cost and clinical success. We performed a cost-utility analysis comparing sartorius flap with NPWT in managing an infected vascular groin graft. A literature review compiling outcomes for sartorius flap and NPWT interventions was conducted from peer-reviewed journals in MEDLINE (PubMed) and EMBASE. Utility scores were derived from expert opinion and used to estimate quality-adjusted life years (QALYs). Medicare current procedure terminology and diagnosis-related groups codes were used to assess the costs for successful graft salvage with the associated complications. Incremental cost-effectiveness was assessed at $50,000/QALY, and both univariate and probabilistic sensitivity analyses were conducted to assess robustness of the conclusions. Thirty-two studies were used pooling 384 patients (234 sartorius flaps and 150 NPWT). NPWT had better clinical outcomes (86.7% success rate, 0.9% minor complication rate, and 13.3% major complication rate) than sartorius flap (81.6% success rate, 8.0% minor complication rate, and 18.4% major complication rate). NPWT was less costly ($12,366 versus $23,516) and slightly more effective (12.06 QALY versus 12.05 QALY) compared with sartorius flap. Sensitivity analyses confirmed the robustness of the base case findings; NPWT was either cost-effective at $50,000/QALY or dominated sartorius flap in 81.6% of all probabilistic sensitivity analyses. In our cost-utility analysis, use of adjunctive NPWT, along with debridement and antibiotic treatment, for managing infected vascular groin graft wounds was found to be a more cost-effective option when compared with sartorius flaps.

  3. Cost-effectiveness analysis alongside a pilot study of prophylactic negative pressure wound therapy.

    Science.gov (United States)

    Heard, Christopher; Chaboyer, Wendy; Anderson, Vinah; Gillespie, Brigid M; Whitty, Jennifer A

    2017-02-01

    Negative pressure wound therapy (NPWT) is increasingly used prophylactically following surgery despite limited evidence of clinical or cost-effectiveness. To evaluate whether NPWT is cost-effective compared to standard care, for the prevention of surgical site infection (SSI) in obese women undergoing elective caesarean section, and inform development of a larger trial. An economic evaluation was conducted alongside a pilot randomised controlled trial at one Australian hospital, in which women were randomised to NPWT (n = 44) or standard care (n = 43). A public health care provider perspective and time horizon to four weeks post-discharge was adopted. Cost-effectiveness assessment was based on incremental cost per SSI prevented and per quality-adjusted life year (QALY) gained. Patients receiving NPWT each received health care costing AU$5887 (±1038) and reported 0.069 (±0.010) QALYs compared to AU$5754 (±1484) and 0.066 (±0.010) QALYs for patients receiving standard care. NPWT may be slightly more costly and more effective than standard care, with estimated incremental cost-effectiveness ratios (ICERs) of AU$1347 (95%CI dominant- $41,873) per SSI prevented and AU$42,340 (95%CI dominant- $884,019) per QALY gained. However, there was considerable uncertainty around these estimates. NPWT may be cost-effective in the prophylactic treatment of surgical wounds following elective caesarean section in obese women. Larger trials could clarify the cost-effectiveness of NPWT as a prophylactic treatment for SSI. Sensitive capture of QALYs and cost offsets will be important given the high level of uncertainty around the point estimate cost-effectiveness ratio which was close to conventional thresholds. ACTRN12612000171819. Copyright © 2016 Tissue Viability Society. Published by Elsevier Ltd. All rights reserved.

  4. Negative pressure wound therapy for Gustilo Anderson grade IIIb open tibial fractures.

    Science.gov (United States)

    Park, Chul Hyun; Shon, Oog Jin; Kim, Gi Beom

    2016-09-01

    Traditionally, Gustilo Anderson grade IIIb open tibial fractures have been treated by initial wide wound debridement, stabilization of fracture with external fixation, and delayed wound closure. The purpose of this study is to evaluate the clinical and radiological results of staged treatment using negative pressure wound therapy (NPWT) for Gustilo Anderson grade IIIb open tibial fractures. 15 patients with Gustilo Anderson grade IIIb open tibial fractures, treated using staged protocol by a single surgeon between January 2007 and December 2011 were reviewed in this retrospective study. The clinical results were assessed using a Puno scoring system for severe open fractures of the tibia at the last followup. The range of motion (ROM) of the knee and ankle joints and postoperative complication were evaluated at the last followup. The radiographic results were assessed using time to bone union, coronal and sagittal angulations and a shortening at the last followup. The mean score of Puno scoring system was 87.4 (range 67-94). The mean ROM of the knee and ankle joints was 121.3° (range 90°-130°) and 37.7° (range 15°-50°), respectively. Bone union developed in all patients and the mean time to union was 25.3 weeks (range 16-42 weeks). The mean coronal angulation was 2.1° (range 0-4°) and sagittal was 2.7° (range 1-4°). The mean shortening was 4.1 mm (range 0-8 mm). Three patients had partial flap necrosis and 1 patient had total flap necrosis. There was no superficial and deep wound infection. Staged treatment using NPWT decreased the risks of infection and requirement of flap surgeries in Gustilo Anderson grade IIIb open tibial fractures. Therefore, staged treatment using NPWT could be a useful treatment option for Gustilo Anderson grade IIIb open tibial fractures.

  5. Expression of HIF-1{alpha} in irradiated tissue is altered by topical negative-pressure therapy

    Energy Technology Data Exchange (ETDEWEB)

    Grimm, A.; Stange, S.; Labanaris, A.; Horch, R.E. [Erlangen-Nuernberg Univ., Erlangen (Germany). Dept. of Plastic and Hand Surgery; Dimmler, A. [Erlangen-Nuernberg Univ., Erlangen (Germany). Dept. of Pathology; Sauer, R.; Grabenbauer, G. [Erlangen-Nuernberg Univ. (Germany). Dept. of Radiation Oncology

    2007-03-15

    Background and Purpose: Despite the enormous therapeutic potential of modern radiotherapy, common side effects such as radiation-induced wound healing disorders remain a well-known clinical phenomenon. Topical negative pressure therapy (TNP) is a novel tool to alleviate intraoperative, percutaneous irradiation or brachytherapy. Since TNP has been shown to positively influence the perfusion of chronic, poorly vascularized wounds, the authors applied this therapeutic method to irradiated wounds and investigated the effect on tissue oxygenation in irradiated tissue in five patients. Material and Methods: With informed patients' consent, samples prior to and 4 and 8 days after continuous TNP with -125 mmHg were obtained during routine wound debridements. Granulation tissue was stained with hematoxylin-eosin, and additionally with CD31, HIF-1{alpha} (hypoxia-inducible factor-1{alpha}), and D2-40 to detect blood vessels, measure indirect signs of hypoxia, and lymph vessel distribution within the pre- and post-TNP samples. Results: In this first series of experiments, a positive influence of TNP onto tissue oxygenation in radiation-induced wounds could be demonstrated. TNP led to a significant decrease of 53% HIF-1{alpha}-positive cell nuclei. At the same time, a slight reduction of CD31-stained capillaries was seen in comparison to samples before TNP. Immunostaining with D2-40 revealed an increased number of lymphatic vessels with distended lumina and an alteration of the parallel orientation within the post-TNP samples. Conclusion: This study is, to the authors' knowledge, the first report on a novel previously not described histological marker to demonstrate the effects of TNP on HIF-1{alpha} expression as an indirect marker of tissue oxygenation in irradiated wounds, as demonstrated by a reduction of HIF-1{alpha} concentration after TNP. Since this observation may be of significant value to develop possible new strategies to treat radiation-induced tissue

  6. Expression of HIF-1α in irradiated tissue is altered by topical negative-pressure therapy

    International Nuclear Information System (INIS)

    Grimm, A.; Stange, S.; Labanaris, A.; Horch, R.E.; Dimmler, A.; Sauer, R.; Grabenbauer, G.

    2007-01-01

    Background and Purpose: Despite the enormous therapeutic potential of modern radiotherapy, common side effects such as radiation-induced wound healing disorders remain a well-known clinical phenomenon. Topical negative pressure therapy (TNP) is a novel tool to alleviate intraoperative, percutaneous irradiation or brachytherapy. Since TNP has been shown to positively influence the perfusion of chronic, poorly vascularized wounds, the authors applied this therapeutic method to irradiated wounds and investigated the effect on tissue oxygenation in irradiated tissue in five patients. Material and Methods: With informed patients' consent, samples prior to and 4 and 8 days after continuous TNP with -125 mmHg were obtained during routine wound debridements. Granulation tissue was stained with hematoxylin-eosin, and additionally with CD31, HIF-1α (hypoxia-inducible factor-1α), and D2-40 to detect blood vessels, measure indirect signs of hypoxia, and lymph vessel distribution within the pre- and post-TNP samples. Results: In this first series of experiments, a positive influence of TNP onto tissue oxygenation in radiation-induced wounds could be demonstrated. TNP led to a significant decrease of 53% HIF-1α-positive cell nuclei. At the same time, a slight reduction of CD31-stained capillaries was seen in comparison to samples before TNP. Immunostaining with D2-40 revealed an increased number of lymphatic vessels with distended lumina and an alteration of the parallel orientation within the post-TNP samples. Conclusion: This study is, to the authors' knowledge, the first report on a novel previously not described histological marker to demonstrate the effects of TNP on HIF-1α expression as an indirect marker of tissue oxygenation in irradiated wounds, as demonstrated by a reduction of HIF-1α concentration after TNP. Since this observation may be of significant value to develop possible new strategies to treat radiation-induced tissue injury, further investigations of HIF

  7. Suture Technique to Prevent Air Leakage during Negative-Pressure Wound Therapy in Fournier Gangrene.

    Science.gov (United States)

    Chang, Feng-Shu; Chou, Chieh; Hu, Chuan-Yu; Huang, Shu-Hung

    2018-01-01

    The use of negative-pressure wound therapy (NPWT) for Fournier gangrene management is well documented; however, it is difficult to fixate GranuFoam dressings and maintain an airtight seal over the perineum area. We developed a simple method to facilitate GranuFoam fixation and improve airtight sealing. The Fournier's gangrene severity index (FGSI) score less than 9 was collected in from January 2015 to October 2016. All 13 patients underwent fasciotomy, and NPWT was applied directly on fasciotomy wounds after the debridement of infected tissue. Partial wound closure was performed, and a portion of GranuFoam was inserted to facilitate fixation. The seal check was converted to a 0-10 scale score that was recorded every 4 hours during NPWT. Patient profiles including medical history, FGSI, method of wound closure, and length of stay were collected in this study. The median age of the patients was 62 (38-76) years. The mean FGSI score was 4.3 ± 3.1. The average duration of NPWT was 17.5 ± 11.5 days, and the average seal check score was 0.8 ± 0.5. No seal check alarms were noted during the study. Successful wound closure was achieved in all patients without using additional reconstruction methods such as skin grafting or muscle flap coverage. The present results suggest that partial wound-edge closure and in situ GranuFoam fixation improve the NPWT leaks in Fournier gangrene wounds. Furthermore, this method is simple to learn and can be useful in applying NPWT to anatomically difficult areas.

  8. Evaluation of a Decision-Making Curriculum for Teaching Adolescents with Disabilities to Resist Negative Peer Pressure

    Science.gov (United States)

    Khemka, Ishita; Hickson, Linda; Mallory, Sarah B.

    2016-01-01

    This study was designed to assess the impact of a decision-making curriculum (PEER-DM) on the social peer relationship knowledge and self-protective decision-making skills of adolescents with disabilities in hypothetical situations involving negative peer pressure. A randomized design was used to assign students with disabilities from…

  9. Major bleeding during negative pressure wound/VAC (R) - therapy for postsurgical deep sternal wound infection - a critical appraisal

    NARCIS (Netherlands)

    van Wingerden, J.J.; Segers, P.; Jekel, L.

    2011-01-01

    Negative-pressure wound therapy, commercially known as vacuum-assisted closure (V.A.C.(R)) therapy, has become one of the most popular (and efficacious) interim (prior to flap reconstruction) or definite methods of managing deep sternal wound infection. Complications such as profuse bleeding, which

  10. Productivity of transcriptionists using a treadmill desk.

    Science.gov (United States)

    Thompson, Warren G; Levine, James A

    2011-01-01

    Time spent sitting increases all-cause mortality. Sedentary occupations are a major contributor to the obesity epidemic. A treadmill desk offers the potential to increase activity while working; however, it is important to make sure that productivity does not decline. The purpose of this study is to evaluate productivity while using a treadmill desk. Eleven experienced medical transcriptionists participated in the study. Transcriptionists were given 4 hours training in the use of a treadmill desk. They were asked to transcribe tapes for 8 hours both while sitting and while using the treadmill desk. Speed and accuracy of transcription were compared as were the average expended calories per hour. The accuracy of transcription did not differ between sitting and walking transcriptions. The speed of transcription was 16% slower while walking than while sitting (p employee obesity and health care costs. However, more than 4 hours of training will be necessary to prevent a significant drop in employee productivity.

  11. Treadmill Desks at LANL - Pilot Study

    Energy Technology Data Exchange (ETDEWEB)

    Fellows, Samara Kia [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-07-28

    It is well established that sedentariness is the largest, preventable contributor to premature death, eclipsing smoking in recent years. One approach to reduce sedentariness is by using a treadmill desk to perform office work while walking at a low speed.We found an increased interest level when the treadmill desks were first introduced to LANL, but after a few months interest appeared to drop. It is possible that treadmill desk use was occurring, but subjects did not record their use. The treadmill desks will not be readily available for purchase by employees due to the study outcome. Additionally, conclusive changes in body measurements could not be performed due to lack of follow up by 58% of the participants.

  12. A comparative study of the efficacy of topical negative pressure moist dressings and conventional moist dressings in chronic wounds

    Directory of Open Access Journals (Sweden)

    Tauro Leo

    2007-01-01

    Full Text Available Aim: To assess the efficacy of topical negative pressure moist wound dressing as compared to conventional moist wound dressings in improving the healing process in chronic wounds and to prove that negative pressure dressings can be used as a much better treatment option in the management of chronic wounds. Materials and Methods: This is a prospective comparative study of data from 112 patients with chronic wounds, of which 56 patients underwent topical negative pressure dressings (17 diabetic, 10 pressure sores, nine ischemic, two varicose, 10 post-infective raw areas and eight traumatic - six had bone exposed, two orthopaedic prosthesis exposed. The remaining 56 patients underwent conventional moist dressings (20 diabetic, two ischemic, 15 pressure sores, three varicose, eight post-infective raw areas and eight traumatic - five had bone exposed, three orthopaedic prosthesis exposed. The results were compared after 10 days. The variables compared were, rate of granulation tissue formation as a percentage of ulcer area covered, skin graft take up as the percentage of ulcer surface area and duration of hospital stay. The variables were compared using Unpaired Student′s t test. A " P" value < 0.05 was considered significant. Results: Out of 56 patients who underwent topical negative pressure dressings, six (10.71% were failures, due to failure in maintaining topical negative pressure due to defective sealing technique; these were included into the study group. After 10 days, the mean rate of granulation tissue formation was 71.43% of ulcer surface area. All these 56 cases underwent split-thickness skin grafting. The mean graft take-up was 79.29%. The mean hospital stay was 32.64 days. In the remaining 56 patients, the mean rate of granulation tissue formation was 52.85% of ulcer surface area. The mean graft take-up was only 60.45% of the total ulcer surface area. The mean hospital stay was 60.45 days. Conclusion: To conclude, topical negative

  13. Cervical spine disease may result in a negative lumbar spinal drainage trial in normal pressure hydrocephalus: case report.

    Science.gov (United States)

    Komotar, Ricardo J; Zacharia, Brad E; Mocco, J; Kaiser, Michael G; Frucht, Stephen J; McKhann, Guy M

    2008-10-01

    In this case report, we present a patient with normal pressure hydrocephalus in whom a lumbar drainage trial yielded a false-negative result secondary to cervical spondylosis. An 80-year-old woman presented with classic symptoms of normal pressure hydrocephalus as well as evidence of cervical myelopathy. Magnetic resonance imaging of the brain and spine showed enlarged ventricles and single-level cervical canal narrowing. An initial lumbar drainage trial was performed, which revealed negative results. The patient then underwent cervical decompression and fusion. Despite this procedure, the patient's symptoms continued to worsen. A repeat lumbar drainage trial was performed with positive results. Subsequently, a ventriculoperitoneal shunt was placed, resulting in significant improvement of her symptoms. This case report illustrates how altered cerebrospinal fluid flow dynamics may impact the accuracy of the lumbar spinal drainage trial in patients with normal pressure hydrocephalus.

  14. The partitioning of nanoparticles to endothelium or interstitium during ultrasound-microbubble-targeted delivery depends on peak-negative pressure

    International Nuclear Information System (INIS)

    Hsiang, Y.-H.; Song, J.; Price, R. J.

    2015-01-01

    Patients diagnosed with advanced peripheral arterial disease often face poor prognoses and have limited treatment options. For some patient populations, the therapeutic growth of collateral arteries (i.e. arteriogenesis) that bypass regions affected by vascular disease may become a viable treatment option. Our group and others are developing therapeutic approaches centered on the ability of ultrasound-activated microbubbles to permeabilize skeletal muscle capillaries and facilitate the targeted delivery of pro-arteriogenic growth factor-bearing nanoparticles. The development of such approaches would benefit significantly from a better understanding of how nanoparticle diameter and ultrasound peak-negative pressure affect both total nanoparticle delivery and the partitioning of nanoparticles to endothelial or interstitial compartments. Toward this goal, using Balb/C mice that had undergone unilateral femoral artery ligation, we intra-arterially co-injected nanoparticles (50 and 100 nm) with microbubbles, applied 1 MHz ultrasound to the gracilis adductor muscle at peak-negative pressures of 0.7, 0.55, 0.4, and 0.2 MPa, and analyzed nanoparticle delivery and distribution. As expected, total nanoparticle (50 and 100 nm) delivery increased with increasing peak-negative pressure, with 50 nm nanoparticles exhibiting greater tissue coverage than 100 nm nanoparticles. Of particular interest, increasing peak-negative pressure resulted in increased delivery to the interstitium for both nanoparticle sizes, but had little influence on nanoparticle delivery to the endothelium. Thus, we conclude that alterations to peak-negative pressure may be used to adjust the fraction of nanoparticles delivered to the interstitial compartment. This information will be useful when designing ultrasound protocols for delivering pro-arteriogenic nanoparticles to skeletal muscle

  15. The partitioning of nanoparticles to endothelium or interstitium during ultrasound-microbubble-targeted delivery depends on peak-negative pressure

    Energy Technology Data Exchange (ETDEWEB)

    Hsiang, Y.-H.; Song, J.; Price, R. J., E-mail: rprice@virginia.edu [University of Virginia, Department of Biomedical Engineering (United States)

    2015-08-15

    Patients diagnosed with advanced peripheral arterial disease often face poor prognoses and have limited treatment options. For some patient populations, the therapeutic growth of collateral arteries (i.e. arteriogenesis) that bypass regions affected by vascular disease may become a viable treatment option. Our group and others are developing therapeutic approaches centered on the ability of ultrasound-activated microbubbles to permeabilize skeletal muscle capillaries and facilitate the targeted delivery of pro-arteriogenic growth factor-bearing nanoparticles. The development of such approaches would benefit significantly from a better understanding of how nanoparticle diameter and ultrasound peak-negative pressure affect both total nanoparticle delivery and the partitioning of nanoparticles to endothelial or interstitial compartments. Toward this goal, using Balb/C mice that had undergone unilateral femoral artery ligation, we intra-arterially co-injected nanoparticles (50 and 100 nm) with microbubbles, applied 1 MHz ultrasound to the gracilis adductor muscle at peak-negative pressures of 0.7, 0.55, 0.4, and 0.2 MPa, and analyzed nanoparticle delivery and distribution. As expected, total nanoparticle (50 and 100 nm) delivery increased with increasing peak-negative pressure, with 50 nm nanoparticles exhibiting greater tissue coverage than 100 nm nanoparticles. Of particular interest, increasing peak-negative pressure resulted in increased delivery to the interstitium for both nanoparticle sizes, but had little influence on nanoparticle delivery to the endothelium. Thus, we conclude that alterations to peak-negative pressure may be used to adjust the fraction of nanoparticles delivered to the interstitial compartment. This information will be useful when designing ultrasound protocols for delivering pro-arteriogenic nanoparticles to skeletal muscle.

  16. Treadmill desks: A 1-year prospective trial.

    Science.gov (United States)

    Koepp, Gabriel A; Manohar, Chinmay U; McCrady-Spitzer, Shelly K; Ben-Ner, Avner; Hamann, Darla J; Runge, Carlisle F; Levine, James A

    2013-04-01

    Sedentariness is associated with weight gain and obesity. A treadmill desk is the combination of a standing desk and a treadmill that allow employees to work while walking at low speed. The hypothesis was that a 1-year intervention with treadmill desks is associated with an increase in employee daily physical activity (summation of all activity per minute) and a decrease in daily sedentary time (zero activity). Employees (n = 36; 25 women, 11 men) with sedentary jobs (87 ± 27 kg, BMI 29 ± 7 kg/m(2) , n = 10 Lean BMI 30 kg/m(2) ) volunteered to have their traditional desk replaced with a treadmill desk to promote physical activity for 1 year. Daily physical activity (using accelerometers), work performance, body composition, and blood variables were measured at Baseline and 6 and 12 months after the treadmill desk intervention. Subjects who used the treadmill desk increased daily physical activity from baseline 3,353 ± 1,802 activity units (AU)/day to, at 6 months, 4,460 ± 2,376 AU/day (P office workers without affecting work performance. Copyright © 2012 The Obesity Society.

  17. Negative pressure wound therapy in complex cranio-maxillofacial and cervical wounds.

    Science.gov (United States)

    Novelli, Giorgio; Daleffe, Francesco; Birra, Gisella; Canzi, Gabriele; Mazzoleni, Fabio; Boni, Pietro; Maino, Clara; Giussani, Carlo; Sozzi, Davide; Bozzetti, Alberto

    2018-02-01

    The care and the management of the healing of difficult wounds at the level of the skull-facial face many problems related to patient compliance and the need to perform multiple dressings, with long periods of healing and, occasionally, a very long hospitalisation period. The introduction and evolution of negative pressure wound therapy (NPWT) in the treatment of difficult wounds has resulted in better healing, with a drastic reduction in terms of time and biological costs to the patient and cost to the health care system. The main aim of this study is to describe and discuss, using out our experience, the usefulness of NPWT in the cranial-facial-cervical region. We studied 16 patients with complex wounds of the cranial-facial-cervical region treated with NPWT. We divided clinical cases in four groups: cervicofacial infectious disease, healing complications in oncological-reconstructive surgery, healing complications of injury with exposure of bone and/or internal fixations and healing complications in traumatic injury with loss of substance. We evaluated complete or incomplete wound healing; application time, related also to hospitalisation time; days of intensive care unit (ICU) stay; management of the upper airways; timing of medication renewal; and patient comfort and compliance (on a scale of 1-5). Depression values were always between -75 and -125 mmHg in a continuous aspiration pattern. For every patient, we used the ActiVAC Therapy Unit, derived from the vacuum-assisted closure system (Kinetic Concepts Inc., San Antonio, TX). Medication renewals were performed every 48-72 hours. The NPWT application time ranged from 4 to 22 days (mean of 11·57 day). Therapy was effective to gain a complete restitutio ad integrum in every patient included in the group of cervicofacial infectious disease. Therapy has, however, been well tolerated in our series; this is probably due to the decreased number of applications, the ease of use and the comfort of the system

  18. Cost analysis of Topical Negative Pressure (TNP Therapy for traumatic acquired wounds

    Directory of Open Access Journals (Sweden)

    Freytag, Sebastian

    2010-01-01

    Full Text Available Extended traumatic wounds require extended reconstructive operations and are accompanied by long hospitalizations and risks of infection, thrombosis and flap loss. In particular, the frequently used Topical Negative Pressure (TNP Therapy is regarded as cost-intensive. The costs of TNP in the context of traumatic wounds is analyzed using the method of health economic evaluation.All patients (n=67: 45 male, 22 female; average age 54 y with traumatically acquired wounds being treated with TNP at the university hospital of Goettingen in the period 01/01/2005–31/12/2007 comprise the basis for this analysis. The concept of activity-based costing based on clinical pathways according to InEK (National Institute for the Hospital Remuneration System systematic calculations was chosen for cost accounting. In addition, a special module system adaptable for individual courses of disease was developed. The treated wounds were located on a lower extremity in 83.7% of cases (n=56 and on an upper extremity in 16.3% of cases (n=11. The average time of hospitalization of the patients was 54 days. Twenty-five patients (37.31% exceeded the „maximum length of stay“ of their associated DRG (Diagnosis Related Groups. The total PCCL (patient clinical complexity level = patient severity score of 2.99 reflects the seriousness of disease. For the treatment of the 67 patients, total costs were $1,729,922.32 (1,249,176.91 €. The cost calculation showed a financial deficit of $–210,932.50 (–152,314.36 €. Within the entire treatment costs of $218,848.07 (158,030.19 €, 12.65% per case were created by TNP with material costs of $102,528.74 (74,036 €, representing 5.92% of entire costs. The cost of TNP per patient averaged $3,266.39 (2,358.66 €. The main portion of the costs was not – as is often expected – due to high material costs of TNP but instead to long-term treatments. Because of their complexity, the cases are insufficiently represented in the

  19. Insomnia complaints in lean patients with obstructive sleep apnea negatively affect positive airway pressure treatment adherence.

    Science.gov (United States)

    Eysteinsdottir, Bjorg; Gislason, Thorarinn; Pack, Allan I; Benediktsdottir, Bryndís; Arnardottir, Erna S; Kuna, Samuel T; Björnsdottir, Erla

    2017-04-01

    The objective of this study was to evaluate the determinants of long-term adherence to positive airway pressure treatment among patients with obstructive sleep apnea, with special emphasis on patients who stop positive airway pressure treatment within 1 year. This is a prospective long-term follow-up of subjects in the Icelandic Sleep Apnea Cohort who were diagnosed with obstructive sleep apnea between 2005 and 2009, and started on positive airway pressure treatment. In October 2014, positive airway pressure adherence was obtained by systematically evaluating available clinical files (n = 796; 644 males, 152 females) with moderate to severe obstructive sleep apnea (apnea-hypopnea index ≥15 events per h). The mean follow-up time was 6.7 ± 1.2 years. In total, 123 subjects (15.5%) returned their positive airway pressure device within the first year, 170 (21.4%) returned it later and 503 (63.2%) were still using positive airway pressure. The quitters within the first year had lower body mass index, milder obstructive sleep apnea, less sleepiness, and more often had symptoms of initial and late insomnia compared with long-term positive airway pressure users at baseline. Both initial and late insomnia were after adjustment still significantly associated with being an early quitter among subjects with body mass index insomnia are associated with early quitting on positive airway pressure among non-obese subjects. © 2016 European Sleep Research Society.

  20. Changes in subcutaneous blood flow during locally applied negative pressure to the skin

    DEFF Research Database (Denmark)

    Skagen, K; Henriksen, O

    1983-01-01

    The effect of locally applied subatmospheric pressure on subcutaneous blood flow was studied in 12 healthy subjects. Blood flow was measured on the forearm by the local 133Xe wash-out technique. Air suction between 10 mmHg and 250 mmHg was applied to the skin. Subatmospheric pressure of 20 mm...

  1. [Efficacy observation on application of negative pressure therapy in the treatment of superficial partial-thickness scald wound in children].

    Science.gov (United States)

    Shen, Chuan-an; Chai, Jia-ke; Tuo, Xiao-ye; Cai, Jian-hua; Li, Dong-jie; Zhang, Lin; Zhu, Hua; Cai, Jin-dong

    2013-02-01

    To observe the effect of negative pressure therapy in the treatment of superficial partial-thickness scald in children. Three hundred and seven children with superficial partial-thickness scald hospitalized from August 2009 to May 2012 were divided into negative pressure therapy group (NPT, n = 145) and control group (C, n = 162) according to the random number table. Patients in group NPT were treated with negative pressure from within post injury day (PID) 3 to PID 9 (with -16 kPa pressure), while traditional occlusive dressing method was used in group C. Changes in body temperature, wound healing condition, frequency of dressing change were compared between group NPT and group C. Bacterial culture results of wounds were compared before and after treatment in group NPT. Volume of drained transudate per one percent of wound area was recorded in group NPT on PID 1 to PID 3. Data were processed with t test or chi-square test. The incidence of high fever was significantly lower in group NPT (26.9%, 39/145) than in group C (63.6%, 103/162, χ(2) = 41.419, P partial-thickness scald.

  2. Negative-pressure in treatment of persistent post-traumatic subcutaneous emphysema with respiratory failure: Case report and literature review

    Directory of Open Access Journals (Sweden)

    Jakov Mihanović

    2018-02-01

    Full Text Available Subcutaneous emphysema may aggravate traumatic pneumothorax treatment, especially when mechanical ventilation is required. Expectative management usually suffices, but when respiratory function is impaired surgical treatment might be indicated. Historically relevant methods are blowhole incisions and placement of various drains, often with related wound complications. Since the first report of negative pressure wound therapy for the treatment of severe subcutaneous emphysema in 2009, only few publications on use of commercially available sets were published. We report on patient injured in a motor vehicle accident who had serial rib fractures and bilateral pneumothorax managed initially in another hospital. Due to respiratory deterioration, haemodynamic instability and renal failure patient was transferred to our Intensive Care Unit. Massive and persistent subcutaneous emphysema despite adequate thoracic drainage with respiratory deterioration and potentially injurious mechanical ventilation with high airway pressures was the indication for active surgical treatment. Negative-pressure wound therapy dressing was applied on typical blowhole incisions which resulted in swift emphysema regression and respiratory improvement. Negative pressure wound therapy for decompression of severe subcutaneous emphysema represents simple, effective and relatively unknown technique that deserves wider attention.

  3. Use of dynamic CT in acute respiratory distress syndrome (ARDS) with comparison of positive and negative pressure ventilation

    Energy Technology Data Exchange (ETDEWEB)

    Helm, Emma; Babyn, Paul [Hospital for Sick Children, Department of Diagnostic Imaging, Toronto (Canada); Talakoub, Omid; Alirezaie, Javad [Ryerson University, Department of Electrical and Computer Engineering, Toronto, ON (Canada); Grasso, Francesco; Engelberts, Doreen; Kavanagh, Brian P. [Hospital for Sick Children and the University of Toronto, Departments of Anesthesia and Critical Care Medicine and the Program in Pulmonary and Experimental Medicine, Toronto (Canada)

    2009-01-15

    Negative pressure ventilation via an external device ('iron lung') has the potential to provide better oxygenation with reduced barotrauma in patients with ARDS. This study was designed to see if oxygenation differences between positive and negative ventilation could be explained by CT. Six anaesthetized rabbits had ARDS induced by repeated saline lavage. Rabbits were ventilated with positive pressure ventilation (PPV) and negative pressure ventilation (NPV) in turn. Dynamic CT images were acquired over the respiratory cycle. A computer-aided method was used to segment the lung and calculate the range of CT densities within each slice. Volumes of ventilated lung and atelectatic lung were measured over the respiratory cycle. NPV was associated with an increased percentage of ventilated lung and decreased percentage of atelectatic lung. The most significant differences in ventilation and atelectasis were seen at mid-inspiration and mid-expiration (ventilated lung NPV=61%, ventilated lung PPV=47%, p<0.001; atelectatic lung NPV=10%, atelectatic lung PPV 19%, p<0.001). Aeration differences were not significant at end-inspiration. Dynamic CT can show differences in lung aeration between positive and negative ventilation in ARDS. These differences would not be appreciated if only static breath-hold CT was used. (orig.)

  4. Effects of topical negative pressure therapy on tissue oxygenation and wound healing in vascular foot wounds.

    Science.gov (United States)

    Chiang, Nathaniel; Rodda, Odette A; Sleigh, Jamie; Vasudevan, Thodur

    2017-08-01

    Topical negative pressure (TNP) therapy is widely used in the treatment of acute wounds in vascular patients on the basis of proposed multifactorial benefits. However, numerous recent systematic reviews have concluded that there is inadequate evidence to support its benefits at a scientific level. This study evaluated the changes in wound volume, surface area, depth, collagen deposition, and tissue oxygenation when using TNP therapy compared with traditional dressings in patients with acute high-risk foot wounds. This study was performed with hospitalized vascular patients. Forty-eight patients were selected with an acute lower extremity wound after surgical débridement or minor amputation that had an adequate blood supply without requiring further surgical revascularization and were deemed suitable for TNP therapy. The 22 patients who completed the study were randomly allocated to a treatment group receiving TNP or to a control group receiving regular topical dressings. Wound volume and wound oxygenation were analyzed using a modern stereophotographic wound measurement system and a hyperspectral transcutaneous oxygenation measurement system, respectively. Laboratory analysis was conducted on wound biopsy samples to determine hydroxyproline levels, a surrogate marker to collagen. Differences in clinical or demographic characteristics or in the location of the foot wounds were not significant between the two groups. All patients, with the exception of two, had diabetes. The two patients who did not have diabetes had end-stage renal failure. There was no significance in the primary outcome of wound volume reduction between TNP and control patients on day 14 (44.2% and 20.9%, respectively; P = .15). Analyses of secondary outcomes showed a significant result of better healing rates in the TNP group by demonstrating a reduction in maximum wound depth at day 14 (36.0% TNP vs 17.6% control; P = .03). No significant findings were found for the other outcomes of changes

  5. The efficacy of negative pressure wound therapy in treating sacroiliac joint tuberculosis with a chronic sinus tract: a case series.

    Science.gov (United States)

    Luo, Xiaobo; Tang, Xiangyu; Ma, Yuanzheng; Zhang, Yonggang; Fang, Shuzhi

    2015-08-06

    Tuberculous sacroiliitis with abscess accounts for approximately 50 % of all sacroiliac joint tuberculosis cases. Tuberculous abscesses spread into the sacroiliac joint capsule, subcutaneous tissue, and the skin, and finally becomes a skin sinus. As there are no previous reports about sacroiliac joint tuberculosis with a chronic sinus, we evaluated its clinical characteristics and management by negative pressure wound therapy. A retrospective analysis of 12 patients with sacroiliac joint tuberculosis with chronic sinuses treated between January 2005 and January 2010 was conducted. Patients were treated with negative pressure wound therapy (NPWT). Treatment was divided into three phases: control phase, standard dressing changes daily for 4 weeks; interphase washout period, dressing changes every 3 days for 1 week; and intervention phase, no dressing changes until minimal sinus tract drainage (sacroiliac joint tuberculosis with a chronic sinus can be difficult. NPWT provides better healing of sacroiliac joint tuberculosis with a chronic sinus than standard dressing changes.

  6. Papineau debridement, Ilizarov bone transport, and negative-pressure wound closure for septic bone defects of the tibia.

    Science.gov (United States)

    Karargyris, Orestis; Polyzois, Vasilios D; Karabinas, Panayiotis; Mavrogenis, Andreas F; Pneumaticos, Spyros G

    2014-08-01

    Ilizarov pioneered bone transport using a circular external fixator. Papineau described a staged technique for the treatment for infected pseudarthrosis of the long bones. This article presents a single-stage Papineau technique and Ilizarov bone transport, and postoperative negative-pressure wound dressing changes for septic bone defects of the tibia. We studied the files of seven patients (mean age, 32 years) with septic bone defects of the tibia treated with a Papineau technique and Ilizarov bone transport in a single stage, followed by postoperative negative-pressure wound dressing changes. All patients had septic pseudarthrosis and skin necrosis of the tibia. The technique included a single-stage extensive surgical debridement of necrotic bone, open bone grafting with cancellous bone autograft and bone transport, and postoperative negative-pressure wound dressing changes for wound closure. The mean time from the initial injury was 6 months (range, 4-8 months). The mean follow-up was 14 months (range, 10-17 months). All patients experienced successful wound healing at a mean of 29 days. Six patients experienced successful bone regeneration and union at the docking side at a mean of 6 months. One patient experienced delayed union at the docking site, which was treated with autologous cancellous bone grafting. Two patients experienced pin track infection, which was successfully treated with antibiotics and pin site dressing changes. All patients were able to return to their work and previous levels of activity, except one patient who had a stiff ankle joint and had to change his job. No patient experienced recurrence of infection, or fracture of the regenerated or transported bone segment until the period of this study. The combined Papineau and Ilizarov bone transport technique with negative-pressure wound closure provides for successful eradication of the infection, reconstruction of the bone defect, and soft-tissue closure. A single-stage surgical treatment is

  7. Comparison of Outcomes for Normal Saline and an Antiseptic Solution for Negative-Pressure Wound Therapy with Instillation.

    Science.gov (United States)

    Kim, Paul J; Attinger, Christopher E; Oliver, Noah; Garwood, Caitlin; Evans, Karen K; Steinberg, John S; Lavery, Larry A

    2015-11-01

    Negative-pressure wound therapy with instillation is an adjunctive treatment that uses periodic instillation of a solution and negative pressure for a wide diversity of wounds. A variety of solutions have been reported, with topical antiseptics as the most frequently chosen option. The objective of this study was to compare the outcomes of normal saline versus an antiseptic solution for negative-pressure wound therapy with instillation for the adjunctive treatment of infected wounds. This was a prospective, randomized, effectiveness study comparing 0.9% normal saline versus 0.1% polyhexanide plus 0.1% betaine for the adjunctive treatment of infected wounds that required hospital admission and operative débridement. One hundred twenty-three patients were eligible, with 100 patients randomized for the intention-to-treat analysis and 83 patients for the per-protocol analysis. The surrogate outcomes measured were number of operative visits, length of hospital stay, time to final surgical procedure, proportion of closed or covered wounds, and proportion of wounds that remained closed or covered at the 30-day follow-up. There were no statistically significant differences in the demographic profiles in the two cohorts except for a larger proportion of male patients (p = 0.004). There was no statistically significant difference in the surrogate outcomes with the exception of the time to final surgical procedure favoring normal saline (p = 0.038). The authors' results suggest that 0.9% normal saline may be as effective as an antiseptic (0.1% polyhexanide plus 0.1% betaine) for negative-pressure wound therapy with instillation for the adjunctive inpatient management of infected wounds. Therapeutic, II.

  8. [The influence of oxygen partial pressure change and vascularization of rabbit wound through negative pressure wound therapy].

    Science.gov (United States)

    Yang, Fan; Hu, Duan; Bai, Xiang-jun; Zhang, Kun; Li, Ren-jie; Xue, Chen-chen

    2012-07-01

    To investigate the effect of vacuum sealing drainage (VSD) on variation of oxygen partial pressure (PtO2) and vascularization. The 12 cases of rabbit's wound models were undergoing the VSD (vacuum group, n = 6) or conventional therapy (conventional group, n = 6). Variation of PtO2 was measured by oxygen partial pressure admeasuring apparatus, expression of hypoxia inducible factor 1α (HIF-1α) mRNA was measured by real-time fluorescent quantitative PCR, content of vascular endothelial growth factor (VEGF) was measured by ELISA after tissue homogenate in 7 days. Vascular endothelial cell (VEC) and new blood capillary (NBC) of hematoxylin-eosin slice of tissue were counted by using light microscope. Average value of PtO2 of vacuum group was significant lower than conventional group (t = -99.780 to -5.305, P < 0.01). Expression of HIF-1α (30 minutes, 1, 6, 12 hours were 3.11 ± 0.07, 3.68 ± 0.26, 4.16 ± 0.13 and 3.91 ± 0.26 respectively) and content of VEGF (30 minutes, 1, 6, 12 hours were 103.3 ± 2.4, 134.2 ± 9.0, 167.8 ± 3.8 and 232.1 ± 9.5 respectively) of vacuum group were increased after 30 minutes and significant lower than conventional group (t = 13.038 - 80.208, P < 0.01), and both of them were reduced after 24 hours (P < 0.05). Counting numbers of VEC (2.47 ± 0.45 to 4.70 ± 0.38) and NBC (1.33 ± 0.49 to 4.33 ± 0.68) of vacuum group were increased at the same time-point and significant higher than conventional group (t = -0.670 to 16.500, P < 0.05). PtO2 of wound surface could be reduced significantly by VSD. Expression of HIF-1α and content of VEGF were increased by VSD for enhancing differentiated state of VEC and construction of NBC, which were better for vascularization and wound healing.

  9. EURAMET.M.P-S9: comparison in the negative gauge pressure range -950 to 0 hPa

    Science.gov (United States)

    Saxholm, S.; Otal, P.; AltintaS, A.; Bermanec, L. G.; Durgut, Y.; Hanrahan, R.; Kocas, I.; Lefkopoulos, A.; Pražák, D.; Sandu, I.; Åetina, J.; Spohr, I.; Steindl, D.; Tammik, K.; Testa, N.

    2016-01-01

    A comparison in the negative gauge pressure range was arranged in the period 2011 - 2012. A total of 14 laboratories participated in this comparison: BEV (Austria), CMI (Czech Republic), DANIAmet-FORCE (Denmark), EIM (Greece), HMI/FSB-LPM (Croatia), INM (Romania), IPQ (Portugal), LNE (France), MCCAA (Malta), METROSERT (Estonia), MIKES (Finland), MIRS/IMT/LMT (Slovenia), NSAI (Ireland) and UME (Turkey). The project was divided into two loops: Loop1, piloted by MIKES, and Loop2, piloted by LNE. The results of the two loops are reported separately: Loop1 results are presented in this paper. The transfer standard was Beamex MC5 no. 25516865 with internal pressure module INT1C, resolution 0.01 hPa. The nominal pressure range of the INT1C is -1000 hPa to +1000 hPa. The nominal pressure points for the comparison were 0 hPa, -200 hPa, -400 hPa, -600 hPa, -800 hPa and -950 hPa. The reference values and their uncertainties as well as the difference uncertainty between the laboratory results and the reference values were determined from the measurement data by Monte Carlo simulations. Stability uncertainty of the transfer standard was included in the final difference uncertainty. Degrees of equivalences and mutual equivalences between the laboratories were calculated. Each laboratory reported results for all twelve measurement points, which means that there were 168 reported values in total. Some 163 of the 168 values (97 %) agree with the reference values within the expanded uncertainties, with a coverage factor k = 2. Among the laboratories, four different methods were used to determine negative gauge pressure. It is concluded that special attention must be paid to the measurements and methods when measuring negative gauge pressures. There might be a need for a technical guide or a workshop that provides information about details and practices related to the measurements of negative gauge pressure, as well as differences between the different methods. The comparison is

  10. A direct method for determining complete positive and negative capillary pressure curves for reservoir rock using the centrifuge

    Energy Technology Data Exchange (ETDEWEB)

    Spinler, E.A.; Baldwin, B.A. [Phillips Petroleum Co., Bartlesville, OK (United States)

    1997-08-01

    A method is being developed for direct experimental determination of capillary pressure curves from saturation distributions produced during centrifuging fluids in a rock plug. A free water level is positioned along the length of the plugs to enable simultaneous determination of both positive and negative capillary pressures. Octadecane as the oil phase is solidified by temperature reduction while centrifuging to prevent fluid redistribution upon removal from the centrifuge. The water saturation is then measured via magnetic resonance imaging. The saturation profile within the plug and the calculation of pressures for each point of the saturation profile allows for a complete capillary pressure curve to be determined from one experiment. Centrifuging under oil with a free water level into a 100 percent water saturated plug results in the development of a primary drainage capillary pressure curve. Centrifuging similarly at an initial water saturation in the plug results in the development of an imbibition capillary pressure curve. Examples of these measurements are presented for Berea sandstone and chalk rocks.

  11. Nonlinear transient dynamic response of pressure relief valves for a negative containment system

    International Nuclear Information System (INIS)

    Aziz, T.S.; Duff, C.G.; Tang, J.H.K.

    1979-01-01

    The response of the piston for the postulated simultaneous effect of pressure and an earthquake is obtained for different parameters and accident conditions. Response quantities such as accelerations, displacements, rotations, diaphragm forces as well as opening time during a design basis earthquake are obtained. The results of the different analyses, as related to the functional operability of the valves, are evaluated and discussed. (orig.)

  12. Perceiving social pressure not to feel negative predicts depressive symptoms in daily life

    NARCIS (Netherlands)

    Dejonckheere, E.; Bastian, B.; Fried, E.I.; Murphy, S.C.; Kuppens, P.

    Background Western societies often overemphasize the pursuit of happiness, and regard negative feelings such as sadness or anxiety as maladaptive and unwanted. Despite this emphasis on happiness, the amount of people suffering from depressive complaints is remarkably high. To explain this apparent

  13. The Ambivalence of Challenge Stressors: Time Pressure Associated with Both Negative and Positive Well-Being

    Science.gov (United States)

    Widmer, Pascale S.; Semmer, Norbert K.; Kalin, Wolfgang; Jacobshagen, Nicola; Meier, Laurenz L.

    2012-01-01

    According to the challenge-hindrance model, challenge stressors contain both stressful and challenging aspects, hindrance stressors only stressful aspects. Typically, negative outcomes of challenge stressors refer to well-being (strain), positive outcomes to so-called work outcomes (e.g., productivity, intention to quit). As both effects occur…

  14. The acute effects of lower limb intermittent negative pressure on foot macro- and microcirculation in patients with peripheral arterial disease.

    Directory of Open Access Journals (Sweden)

    Øyvind Heiberg Sundby

    Full Text Available Intermittent negative pressure (INP applied to the lower leg and foot increases foot perfusion in healthy volunteers. The aim of the present study was to describe the effects of INP to the lower leg and foot on foot macro- and microcirculation in patients with lower extremity peripheral arterial disease (PAD.In this experimental study, we analyzed foot circulation during INP in 20 patients [median (range: 75 (63-84yrs] with PAD. One leg was placed inside an air-tight vacuum chamber connected to an INP-generator. During application of INP (alternating 10s of -40mmHg/7s of atmospheric pressure, we continuously recorded blood flow velocity in a distal foot artery (ultrasound Doppler, skin blood flow on the pulp of the first toes (laser Doppler, heart rate (ECG, and systemic blood pressure (Finometer. After a 5-min baseline sequence (no pressure, a 10-min INP sequence was applied, followed by 5-min post-INP (no pressure. To compare and quantify blood flow fluctuations between sequences, we calculated cumulative up-and-down fluctuations in arterial blood flow velocity per minute.Onset of INP induced an increase in arterial flow velocity and skin blood flow. Peak blood flow velocity was reached 3s after the onset of negative pressure, and increased 46% [(95% CI 36-57, P<0.001] above baseline. Peak skin blood flow was reached 2s after the onset of negative pressure, and increased 89% (95% CI 48-130, P<0.001 above baseline. Cumulative fluctuations per minute were significantly higher during INP-sequences compared to baseline [21 (95% CI 12-30cm/s/min to 41 (95% CI 32-51cm/s/min, P<0.001]. Mean INP blood flow velocity increased significantly ~12% above mean baseline blood flow velocity [(6.7 (95% CI 5.2-8.3cm/s to 7.5 (95% CI 5.9-9.1cm/s, P = 0.03].INP increases foot macro- and microcirculatory flow pulsatility in patients with PAD. Additionally, application of INP resulted in increased mean arterial blood flow velocity.

  15. Negative pressure of the environmental air in the cleaning area of the materials and sterilization center: a systematic review

    Directory of Open Access Journals (Sweden)

    Caroline Lopes Ciofi-Silva

    Full Text Available ABSTRACT Objective: to analyze the scientific evidence on aerosols generated during cleaning activities of health products in the Central Service Department (CSD and the impact of the negative pressure of the ambient air in the cleaning area to control the dispersion of aerosols to adjacent areas. Method: for this literature systematic review the following searches were done: search guidelines, manuals or national and international technical standards given by experts; search in the portal and databases PubMed, Scopus, CINAHL and Web of Science; and a manual search of scientific articles. Results: the five technical documents reviewed recommend that the CSD cleaning area should have a negative differential ambient air pressure, but scientific articles on the impact of this intervention were not found. The four articles included talked about aerosols formed after the use of a ultrasonic cleaner (an increased in the contamination especially during use and pressurized water jet (formation of smaller aerosols 5μm. In a study, the aerosols formed from contaminated the hot tap water with Legionella pneumophila were evaluated. Conclusions: there is evidence of aerosol formation during cleanup activities in CSD. Studies on occupational diseases of respiratory origin of workers who work in CSD should be performed.

  16. The Influence of the Bed with a Semiopen Hood on Bacteria Removal in a Negative-Pressure Isolation Room

    Directory of Open Access Journals (Sweden)

    Jeng-Min Huang

    2014-06-01

    Full Text Available This study numerically investigates the influence of a sickbed with a semiopened hood on bacteria removal in a negative-pressure isolation room. The parameters include air change rate, lying style, the length and height of hood, flow rate allotments, and the positions of outlets. The results show that the hood has excellent effect on the removal of contaminated air, which is much better than the case without hood. The flow field of patient's face up cough is very different from face side cough, and the contaminated air cannot be removed properly through one air outlet. There are three outlets on the hood, set straight above the patient's face and at both sides. The allotment of the exhaust flow rate of the upper outlet to that of side outlets is suggested to be 4: 6. When the total air change rate is above 6 ACH, the hood length has slight influence on pollutant removal. The increase of hood height has a negative impact when the patient coughs lying on back. When the side exhaust flow rate is high, the hood height has a slight impact for face side cough. The recommended air change rate for the negative-pressure ward with sickbed hood is above 5 ACH.

  17. Impact of microarousal associated with increased negative esophageal pressure in sleep-disordered breathing.

    Science.gov (United States)

    Sukegawa, Mayo; Noda, Akiko; Yasuda, Yoshinari; Nakata, Seiichi; Sugiura, Tatsuki; Miyata, Seiko; Honda, Kumiko; Hasegawa, Yoshinori; Nakashima, Tsutomu; Koike, Yasuo

    2009-11-01

    "Microarousals" during sleep have not been analyzed systematically. We investigated the importance of "microarousals" (lasting 1.5-3 s). Standard polysomnography including esophageal pressure (Pes) assessment was performed on ten patients (aged 54.0 +/- 5.0 years) with respiratory effort-related arousal > or =5/h. We measured the number of arousals per hour (American Sleep Disorders Association (ASDA) arousal index) and the number of microarousals lasting 1.5-3 s per hour (mASDA arousal index). On the night after the baseline sleep study, we performed overnight continuous positive airway pressure (CPAP) titration. mASDA arousals, characterized by lower Pes values, were observed more frequently in patients with sleep-disordered breathing. The Pes results did not differ significantly between ASDA and mASDA arousals (-15.6 +/- -5.0 vs -15.0 +/- -4.4 cmH(2)O). mASDA arousals were significantly improved by CPAP treatment (mASDA arousals, 82.6 +/- 60.1 vs 6.0 +/- 1.4/h). mASDA arousals were characterized by an increase in Pes. mASDA arousals are thus key to our understanding of clinical manifestations in patients with sleep-disordered breathing.

  18. Comparisons of negative pressure wound therapy and ultrasonic debridement for diabetic foot ulcers: a network meta-analysis.

    Science.gov (United States)

    Wang, Ruran; Feng, Yanhua; Di, Bo

    2015-01-01

    a network meta-analysis was performed to compare the strength and weakness of negative pressure wound therapy (NPWT) with ultrasound debridement (UD) as for diabetic foot ulcers (DFU). PubMed, Ovid EMBASE, Web of Science, Cochrane library databases, and Chinese Biomedical Literature Database were searched till February 2015. Clinical compared studies of negative pressure wound therapy and ultrasound debridement were enrolled. The primary efficacy outcomes included healed ulcers, reduction of ulcer areas and time to closure. Secondary amputation including major and minor amputations was used to assess the safety profile. Out of 715 studies, 32 were selected which enrolled 2880 diabetic patients. The pooled analysis revealed that NPWT including vacuum assisted closure (VAC) and vacuum sealing drainage (VSD) were as efficacious as ultrasound debridement improving healed ulcers, odds ratio, 0.86; 95% CI 0.28 to 2.6 and 1.2; 95% CI 0.38 to 4, respectively. However, both were better to standard wound care in wound healing patients. Compared with the standard wound care treated diabetic foot ulcers, NPWT and UD resulted in a significantly superior efficacy in time to wound closure and decrement in area of wound. No significances were observed between NPWT and UD groups in both indicators. Fewer patients tended to receive amputation in NPWT and UD groups compared to standard wound care group. The results of the network meta-analysis indicated that negative pressure wound therapy was similar to ultrasound debridement for diabetic foot ulcers, but better than standard wound care both in efficacy and safety profile.

  19. Comparisons of negative pressure wound therapy and ultrasonic debridement for diabetic foot ulcers: a network meta-analysis

    Science.gov (United States)

    Wang, Ruran; Feng, Yanhua; Di, Bo

    2015-01-01

    Objective: a network meta-analysis was performed to compare the strength and weakness of negative pressure wound therapy (NPWT) with ultrasound debridement (UD) as for diabetic foot ulcers (DFU). Methods: PubMed, Ovid EMBASE, Web of Science, Cochrane library databases, and Chinese Biomedical Literature Database were searched till February 2015. Clinical compared studies of negative pressure wound therapy and ultrasound debridement were enrolled. The primary efficacy outcomes included healed ulcers, reduction of ulcer areas and time to closure. Secondary amputation including major and minor amputations was used to assess the safety profile. Results: Out of 715 studies, 32 were selected which enrolled 2880 diabetic patients. The pooled analysis revealed that NPWT including vacuum assisted closure (VAC) and vacuum sealing drainage (VSD) were as efficacious as ultrasound debridement improving healed ulcers, odds ratio, 0.86; 95% CI 0.28 to 2.6 and 1.2; 95% CI 0.38 to 4, respectively. However, both were better to standard wound care in wound healing patients. Compared with the standard wound care treated diabetic foot ulcers, NPWT and UD resulted in a significantly superior efficacy in time to wound closure and decrement in area of wound. No significances were observed between NPWT and UD groups in both indicators. Fewer patients tended to receive amputation in NPWT and UD groups compared to standard wound care group. Conclusions: The results of the network meta-analysis indicated that negative pressure wound therapy was similar to ultrasound debridement for diabetic foot ulcers, but better than standard wound care both in efficacy and safety profile. PMID:26550165

  20. Topical negative pressure therapy Recent experience of the department of plastic surgery at Ibn Sina University Hospital, Rabat, Morocco

    Directory of Open Access Journals (Sweden)

    Abdelmoughit Echchaoui

    2014-12-01

    Full Text Available IntroductionThe topical negative pressure therapy (TNP is a non-invasive method to treat chronic and acute wounds locally, using a continuous or intermittent negative pressure.The objective of this study is to present the first experience of this type of treatment used in clinical cases in our department. By presenting these cases, we highlight indication and efficiency of this new technique applied in relatively complicated situations, at the same time it also allows a significant improvement in treating injuries and chronic wounds.Materials and methodsIn this study, we present the recent experience of the Department of Reconstructive and Plastic Surgery of the University Hospital Center of Avicenne in Rabat. This therapy was used for the first time this year (in 2014, in three young patients who presented with chronic wounds associated with local and general factors that are unfavorable for the healing process.ResultsIn all three of our cases we obtained highly satisfactory clinical results.TNP allows wounds to bud in a shorter time, as well as a fast healing by second intention due to controlled wound healing or split-skin graft without using flaps. This enables to decrease the margin of error, the time and the number of dressing replacements, and to reduce the length of hospital stay.ConclusionThis is an expensive and specific equipment. However, the cost-benefit ratio analysis shows that it is an essential method that should be part of our therapeutic strategies.Keywords: loss of substance, negative pressure, budding, healing.  

  1. Negative Pressure Wound Therapy in Infected Wound following Posterior Spinal Instrumentation using Simple Self-assembled System: A Case Report

    Directory of Open Access Journals (Sweden)

    CW Chang

    2014-07-01

    Full Text Available Postoperative wound infection in an instrumented spine patient is often disastrous. Management includes implant removal leading to spine instability. Negative pressure wound therapy (NPWT applied to the spine surgical wound is one of the wound care technique with successful results. We report a case of a man who sustained Chance fracture of Lumbar 1 (L1 vertebra treated with long segment posterior instrumentation, who unfortunately developed Extended-spectrum beta-lactamase (ESBL positive E. coli infection one month after the operation. After careful debridement of the wound, the implant became exposed. Three cycles of NPWT were applied and the wound healed with granulation tissue completely covering the implant, and thus negating the need to remove the implant. In conclusion, the NPWT is a good alternative in postoperative wound management especially in an instrumented spine patient.

  2. The Influence of the Bed with a Semiopen Hood on Bacteria Removal in a Negative-Pressure Isolation Room

    OpenAIRE

    Jeng-Min Huang; Hsiang-Tai Cheng

    2014-01-01

    This study numerically investigates the influence of a sickbed with a semiopened hood on bacteria removal in a negative-pressure isolation room. The parameters include air change rate, lying style, the length and height of hood, flow rate allotments, and the positions of outlets. The results show that the hood has excellent effect on the removal of contaminated air, which is much better than the case without hood. The flow field of patient's face up cough is very different from face side coug...

  3. A Unique Application of Negative Pressure Wound Therapy Used to Facilitate Patient Engagement in the Amputation Recovery Process.

    Science.gov (United States)

    Wise, Jessica; White, Alicia; Stinner, Daniel J; Fergason, John R

    2017-08-01

    Amputation rates during recent military conflicts were at an all-time high, but medical treatment of those amputations and attitudes of service members to get back to duty are also surging ahead. We present the cases of an active duty rescue C130 pilot with an above-the-knee amputation and a retired army sergeant with a below-the-knee amputation. Successful rehabilitation was augmented in both cases by using negative pressure incorporated in a custom prosthetic socket to accelerate incision closure, improve self-efficacy in wound care, and self-management, ultimately leading to faster recovery times, full engagement of the rehabilitation process, and return to active duty.

  4. Cost-effectiveness of negative pressure wound therapy in patients with many comorbidities and severe wounds of various etiology.

    Science.gov (United States)

    Driver, Vickie R; Eckert, Kristen A; Carter, Marissa J; French, Michael A

    2016-11-01

    This study analyzed a cross-section of patients with severe chronic wounds and multiple comorbidities at an outpatient wound clinic, with regard to the cost-effectiveness and cost-benefit of negative pressure wound therapy (intervention) vs. no negative pressure wound therapy (control) at 1 and 2 years. Medicare reimbursement charges for wound care were used to calculate costs. Amputation charges were assessed using diagnosis-related groups. Cost-benefit analysis was based on ulcer-free months and cost-effectiveness on quality-adjusted life-years. Undiscounted costs, benefits, quality-adjusted life-years, undiscounted and discounted incremental net health benefits, and incremental cost-effectiveness ratios were calculated for unmatched and matched cohorts. There were 150 subjects in the intervention group and 154 controls before matching and 103 subjects in each of the matched cohorts. Time to heal for the intervention cohort was significantly shorter compared to the controls (270 vs. 635 days, p = 1.0 × 10 -7 , matched cohorts). The intervention cohort had higher benefits and quality-adjusted life-year gains compared to the control cohort at years 1 and 2; by year 2, the gains were 68-73% higher. In the unmatched cohorts, the incremental net health benefit was $9,933 per ulcer-free month at year 2 for the intervention; the incremental cost-effectiveness ratio was -825,271 per quality-adjusted life-year gained (undiscounted costs and benefits). For the matched cohorts, the incremental net health benefits was only $1,371 per ulcer-free month for the intervention, but the incremental cost-effectiveness ratio was $366,683 per quality-adjusted life-year gained for year 2 (discounted costs and benefits). In a patient population with severe chronic wounds and serious comorbidities, negative pressure wound therapy resulted in faster healing wounds and was more cost-effective with greater cost-benefits than not using negative pressure wound therapy. Regarding overall

  5. Hemodynamic responses to seated and supine lower body negative pressure - Comparison with +Gz acceleration

    Science.gov (United States)

    Polese, Alvese; Sandler, Harold; Montgomery, Leslie D.

    1992-01-01

    The hemodynamic responses to LBNP in seated subjects and in subjects in supine body positions were compared and were correlated with hemodynamic changes which occurred during a simulated (by centrifugation) Shuttle reentry acceleration with a slow onset rate of 0.002 G/s and during gradual onset exposures to +3 Gz and +4 Gz. Results demonstrate that seated LBNP at a level of -40 mm Hg can serve as a static simulator for changes in the heart rate and in mean blood pressure induced by gradual onset acceleration stress occurring during Shuttle reentry. The findings also provide a rationale for using LBNP during weightlessness as a means of imposing G-loading on the circulation prior to reentry.

  6. Hemolysis During Open-Heart Surgery With Vacuum-Assisted Venous Drainage at Different Negative Pressures in Pediatric Patients Weighing Less Than 10 kilograms.

    Science.gov (United States)

    Kwak, Jae Gun; Lee, Jinkwon; Park, Minkyoung; Seo, Yu-Jin; Lee, Chang-Ha

    2017-03-01

    This study examined the degree of hemolysis during vacuum-assisted venous drainage at different negative pressures to identify an adequate negative pressure that provides effective venous drainage without significant hemolysis in open-heart surgery in children weighing less than 10 kg. Patients weighing less than 10 kg who underwent surgery for ventricular septal defect or atrial septal defect from 2011 to 2014 were enrolled. We used one of four negative pressures (20, 30, 40, or 60 mm Hg) for each patient. We measured haptoglobin, plasma hemoglobin, aspartate aminotransferase, and lactate dehydrogenase levels in the patients' blood three times perioperatively and determined the potential correlation between the change in each parameter with the level of negative pressure. Forty-six patients were enrolled in this study (mean age: 7.1 ± 7.0 months, mean body weight: 6.1 ± 1.8 kg). There were no significant differences according to the degree of negative pressure with respect to patient age, body weight, cardiopulmonary bypass (CPB) time, aorta cross-clamping time, blood flow during CPB, or lowest body temperature. All parameters that we measured reflected progression of hemolysis during CPB; however, the degree of change in the parameters did not correlate with negative pressure. In pediatric patients weighing less than 10 kg, the change in the degree of hemolysis did not differ with the amount of negative pressure. We may apply negative pressures up to 60 mm Hg without increasing the risk of hemolysis, with almost same the level of hemolysis using negative pressures of 20, 30, and 40 mm Hg for effective venous drainage and an ideal operative field during open-heart surgery.

  7. Impact of chemical peeling combined with negative pressure on human skin.

    Science.gov (United States)

    Kim, S J; Kang, I J; Shin, M K; Jeong, K H; Baek, J H; Koh, J S; Lee, S J

    2016-10-01

    In vivo changes in skin barrier function after chemical peeling with alpha hydroxyacids (AHAs) have been previously reported. However, the additional effects of physical treatment with chemical agents on skin barrier function have not been adequately studied. This study measured the degree of acute skin damage and the time required for skin barrier repair using non-invasive bioengineering methods in vivo with human skin to investigate the additional effect of a 4% AHA chemical jet accelerated at supersonic velocities. Thirteen female subjects (average age: 29.54 ± 4.86 years) participated in this study. The faces of the subjects were divided into half according to the block randomization design and were then assigned to receive AHA peeling alone or AHA peeling combined with pneumatic pressure on each side of the face. Transepidermal water loss (TEWL), skin colour and skin blood flow were evaluated at baseline and at 30 min, 2, 5 and 7 days after treatment. The TEWL and skin blood flow were significantly increased after 30 min in chemodermabrasion compared with chemical peeling alone (P peeling alone (P < 0.05). Chemodermabrasion can temporarily impair skin barriers, but it is estimated that it can enhance the skin barrier function after 7 days compared to the use of a chemical agent alone. In addition, chemodermabrasion has a more effective impact in the dermis and relatively preserves the skin barrier. © 2016 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

  8. The efficacy of negative pressure wound therapy in the management of lower extremity trauma: review of clinical evidence.

    Science.gov (United States)

    Kanakaris, N K; Thanasas, C; Keramaris, N; Kontakis, G; Granick, Mark S; Giannoudis, P V

    2007-12-01

    A large number of aids have been conceived and introduced into clinical practice (nutritional supplements, local dressings, technical innovations) aimed at facilitating and optimising wound healing in both acute and chronic wound settings. Among these advances, negative pressure wound therapy (NPWT) has been introduced during the last 30 years, and has been analysed in over 400 manuscripts of the English, Russian and German literature. Until very recently, vacuum assisted closure (VAC) (KCI, TX, USA) has been the only readily available commercial device that provides localised negative pressure to the wound and is the predominant agent used to deliver NPWT featured in this review. We conducted a comprehensive review of the existing clinical evidence of the English literature on the applications of NPWT in the acute setting of trauma and burns of the lower extremity. Overall, 16 clinical studies have been evaluated and scrutinised as to the safety and the efficacy of this adjunct therapy in the specific environment of trauma. Effectiveness was comparable to the standard dressing and wound coverage methods. The existing clinical evidence justifies its application in lower limb injuries associated with soft tissue trauma.

  9. Measurement of negative ion mobility in O2 at high pressures using a point plate gap as an ion detector

    International Nuclear Information System (INIS)

    Okuyama, Y; Kimura, T; Suzuki, S; Itoh, H

    2012-01-01

    This paper describes the experimental results for negative ion mobility in O 2 at 0.5-2.0 atm. The ion mobility is observed using a high-pressure ion drift tube with a positive corona gap (Geiger counter), which is constructed from a point plate gap and acts as a negative ion detector. The variation of waveforms in the burst pulse is observed by varying the voltage applied to the ion detector to find the optimum voltage that must be applied across the ion detector in O 2 . This is investigated carefully to ensure the precise determination of mobility. The distortion of the electric field near the mesh electrode, which operates as the cathode of the ion detector and as the anode of the ion drift gap, is then examined to determine the optimum applied voltage to suppress its effect on the measurement of mobility. The mobility is subsequently measured at a reduced electric field intensity of 2.83 × 10 -3 to 2.83. The observed mobility of 2.31 ± 0.03 cm 2 V -1 s -1 in O 2 is concluded to be that of O 2 - . This value is also obtained in experiments over a wide range of gas pressures (0.5-2.0 atm) and drift lengths (1.00-9.00 cm). The mobilities of O 3 - and O - are also obtained experimentally. (paper)

  10. Intermittent negative pressure wound therapy with instillation for the treatment of persistent periprosthetic hip infections: a report of two cases

    Directory of Open Access Journals (Sweden)

    Söylemez MS

    2016-02-01

    Full Text Available Mehmet Salih Söylemez,1 Korhan Özkan,2 Bülent Kılıç,3 Samet Erinç41Department of Orthopaedics and Traumatology, Bingöl State Hospital, Bingöl, 2Department of Orthopaedics and Traumatology, Faculty of Medicine, Medeniyet University, Istanbul, 3Department of Orthopaedics and Traumatology, Orthopaedic Surgery Clinic, Istanbul Gelişim University, Tekirdağ, 4Department of Orthopaedics and Traumatology, Istanbul Medeniyet University, Göztepe Training and Research Hospital, Istanbul, TurkeyAbstract: Intermittent negative pressure wound therapy with instillation (NPWTi is starting to be used successfully to treat early periprosthetic infections of endoprostheses. However, few articles have reported the outcome of treatment with intermittent NPWTi for late persistent periprosthetic infections of the hip. In this study, we report two cases who underwent several rounds of radical wound debridement for the treatment of a late persistent periprosthetic infection of the hip. Intermittent NPWTi was used in both cases. Patients were treated successfully and there was no recurrence after 3 and 1 years of follow-up, respectively.Keywords: negative pressure, vacuum-assisted, periprosthetic infection, hip

  11. Design and Validation of an Instrumented Uneven Terrain Treadmill.

    Science.gov (United States)

    Voloshina, Alexandra S; Ferris, Daniel P

    2018-06-01

    Studying human and animal locomotion on an uneven terrain can be beneficial to basic science and applied studies for clinical and robotic applications. Traditional biomechanical analysis of human locomotion has often been limited to laboratory environments with flat, smooth runways and treadmills. The authors modified a regular exercise treadmill by attaching wooden blocks to the treadmill belt to yield an uneven locomotion surface. To ensure that these treadmill modifications facilitated biomechanical measurements, the authors compared ground reaction force data collected while a subject ran on the modified instrumented treadmill with a smooth surface with data collected using a conventional instrumented treadmill. Comparisons showed only minor differences. These results suggest that adding an uneven surface to a modified treadmill is a viable option for studying human or animal locomotion on an uneven terrain. Other types of surfaces (eg, compliant blocks) could be affixed in a similar manner for studies on other types of locomotion surfaces.

  12. Metabolic Rate and Ground Reaction Force During Motorized and Non-Motorized Treadmill Exercise

    Science.gov (United States)

    Everett, Meghan E.; Loehr, James A.; DeWitt, John K.; Laughlin, Mitzi; Lee, Stuart M. C.

    2010-01-01

    PURPOSE: To measure vertical ground reaction force (vGRF) and oxygen consumption (VO2) at several velocities during exercise using a ground-based version of the ISS treadmill in the M and NM modes. METHODS: Subjects (n = 20) walked or ran at 0.89, 1.34, 1.79, 2.24, 2.68, and 3.12 m/s while VO2 and vGRF data were collected. VO2 was measured using open-circuit spirometry (TrueOne 2400, Parvo-Medics). Data were averaged over the last 2 min of each 5-min stage. vGRF was measured in separate 15-s bouts at 125 Hz using custom-fitted pressure-sensing insoles (F-Scan Sport Sensors, Tekscan, Inc). A repeated-measures ANOVA was used to test for differences in VO2 and vGRF between M and NM and across speeds. Significance was set at P < 0.05. RESULTS: Most subjects were unable to exercise for 5 min at treadmill speeds above 1.79 m/s in the NM mode; however, vGRF data were obtained for all subjects at each speed in both modes. VO2 was approx.40% higher during NM than M exercise across treadmill speeds. vGRF increased with treadmill speed but was not different between modes. CONCLUSION: Higher VO2 with no change in vGRF suggests that the additional metabolic cost associated with NM treadmill exercise is accounted for in the horizontal forces required to move the treadmill belt. Although this may limit the exercise duration at faster speeds, high-intensity NM exercise activates the hamstrings and plantarflexors, which are not specifically targeted or well protected by other in-flight countermeasures.

  13. Relationship quality: effects on ambulatory blood pressure and negative affect in a biracial sample of men and women.

    Science.gov (United States)

    Grewen, Karen M; Girdler, Susan S; Light, Kathleen C

    2005-06-01

    Prospective studies link marriage to better cardiovascular health, but marital dissatisfaction and discord predict increased rates of hypertension, higher blood pressure (BP), greater reactivity to stress, and left ventricular mass. To determine and compare effects of partner status and relationship quality on 24-h BP, urinary norepinephrine and cortisol, and self-reported stress and negative affect. Ambulatory BP (ABP) and 24-h urine collections were obtained during a typical work day in 325 adults, including 139 African Americans (AAs). Participants cohabiting with a spouse or partner were classified into high, intermediate and low relationship quality (RQ) groups and compared to those without partners (Alone). Mean ABP was nearly identical in participants with versus without partners (125.7/76.9 versus 125.9/76.7 mmHg). High RQ subjects had lower mean waking ABP than intermediate/low RQ and Alone groups [systolic blood pressure (SBP), F=3.45; diastolic blood pressure (DBP), F=3.38, P-values affect and stress than all other groups (Paffect and stress than partner status. High RQ is linked to lower ABP across race and gender. This reduced ABP may be due, in part, to the stress buffering effects of better RQ and/or the stress enhancing effects of poor RQ.

  14. Effect of Negative Pressure on Proliferation, Virulence Factor Secretion, Biofilm Formation, and Virulence-Regulated Gene Expression of Pseudomonas aeruginosa In Vitro

    Directory of Open Access Journals (Sweden)

    Guo-Qi Wang

    2016-01-01

    Full Text Available Objective. To investigate the effect of negative pressure conditions induced by NPWT on P. aeruginosa. Methods. P. aeruginosa was cultured in a Luria–Bertani medium at negative pressure of −125 mmHg for 24 h in the experimental group and at atmospheric pressure in the control group. The diameters of the colonies of P. aeruginosa were measured after 24 h. ELISA kit, orcinol method, and elastin-Congo red assay were used to quantify the virulence factors. Biofilm formation was observed by staining with Alexa Fluor® 647 conjugate of concanavalin A (Con A. Virulence-regulated genes were determined by quantitative RT-PCR. Results. As compared with the control group, growth of P. aeruginosa was inhibited by negative pressure. The colony size under negative pressure was significantly smaller in the experimental group than that in the controls (p<0.01. Besides, reductions in the total amount of virulence factors were observed in the negative pressure group, including exotoxin A, rhamnolipid, and elastase. RT-PCR results revealed a significant inhibition in the expression level of virulence-regulated genes. Conclusion. Negative pressure could significantly inhibit the growth of P. aeruginosa. It led to a decrease in the virulence factor secretion, biofilm formation, and a reduction in the expression level of virulence-regulated genes.

  15. DC negative corona discharge in atmospheric pressure helium: transition from the corona to the ‘normal’ glow regime

    International Nuclear Information System (INIS)

    Hasan, Nusair; Farouk, Bakhtier; Antao, Dion S

    2014-01-01

    Direct current (dc) negative corona discharges in atmospheric pressure helium are simulated via detailed numerical modeling. Simulations are conducted to characterize the discharges in atmospheric helium for a pin plate electrode configuration. A self-consistent two-dimensional hybrid model is developed to simulate the discharges and the model predictions are validated with experimental measurements. The discharge model considered consists of momentum and energy conservation equations for a multi-component (electrons, ions, excited species and neutrals) gas mixture, conservation equations for each component of the mixture and state relations. A drift–diffusion approximation for the electron and the ion fluxes is used. A model for the external circuit driving the discharge is also considered and solved along with the discharge model. Many of the key features of a negative corona discharge, namely non-linear current–voltage characteristics, spatially flat cathode current density and glow-like discharge in the high current regime are displayed in the predictions. A transition to the ‘normal’ glow discharge from the corona discharge regime is also observed. The transition is identified from the calculated current–voltage characteristic curve and is characterized by the radial growth of the negative glow and the engulfment of the cathode wire. (paper)

  16. Treadmill walking with body weight support

    OpenAIRE

    Aaslund, Mona Kristin

    2012-01-01

    Background: Rehabilitating walking in patients post-stroke with safe, task-specific, intensive training of sufficient duration, can be challenging. Body weight supported treadmill training (BWSTT) has been proposed as an effective method to meet these challenges and may therefore have benefits over training overground walking. However, walking characteristics should not be aggravated during BWSTT or require a long familiarisation time compared to overground walking. Objectives: To investi...

  17. The concept of negative pressure wound therapy (NPWT after poststernotomy mediastinitis – a single center experience with 54 patients

    Directory of Open Access Journals (Sweden)

    Vogt Peter M

    2009-01-01

    Full Text Available Abstract Deep sternal infections, also known as poststernotomy mediastinitis, are a rare but often fatal complication in cardiac surgery. They are a cause of increased morbidity and mortality and have a significant socioeconomic aspect concerning the health system. Negative pressure wound therapy (NPWT followed by muscular pectoralis plasty is a quite new technique for the treatment of mediastinitis after sternotomy. Although it could be demonstrated that this technique is at least as safe and reliable as other techniques for the therapy of deep sternal infections, complications are not absent. We report about our experiences and complications using this therapy in a set of 54 patients out of 3668 patients undergoing cardiac surgery in our institution between January 2005 and April 2007.

  18. The concept of negative pressure wound therapy (NPWT) after poststernotomy mediastinitis--a single center experience with 54 patients.

    Science.gov (United States)

    Ennker, Ina C; Malkoc, Anita; Pietrowski, Detlef; Vogt, Peter M; Ennker, Juergen; Albert, Alexander

    2009-01-12

    Deep sternal infections, also known as poststernotomy mediastinitis, are a rare but often fatal complication in cardiac surgery. They are a cause of increased morbidity and mortality and have a significant socioeconomic aspect concerning the health system. Negative pressure wound therapy (NPWT) followed by muscular pectoralis plasty is a quite new technique for the treatment of mediastinitis after sternotomy. Although it could be demonstrated that this technique is at least as safe and reliable as other techniques for the therapy of deep sternal infections, complications are not absent. We report about our experiences and complications using this therapy in a set of 54 patients out of 3668 patients undergoing cardiac surgery in our institution between January 2005 and April 2007.

  19. Experience with the vacuum assisted closure negative pressure technique in the treatment of non-healing diabetic and dysvascular wounds.

    Science.gov (United States)

    Clare, Michael P; Fitzgibbons, Timothy C; McMullen, Scott T; Stice, R Colleen; Hayes, Dennis F; Henkel, Loree

    2002-10-01

    The purpose of this study is to report our experience with the Vacuum Assisted Closure (VAC) negative pressure technique in patients with non-healing wounds of the foot, ankle, and lower limb. We retrospectively reviewed 17 patients with non-healing wounds of the lower extremity who underwent treatment using the Vacuum Assisted Closure (VAC) device. Thirteen of 17 (76%) had diabetes mellitus, nine of whom were insulin-dependent, and 10 of whom had associated peripheral neuropathy. Eight of 17 (47%) had severe peripheral vascular disease. All had failed previous management with serial wound debridements and dressing changes; 15 of 17 (88%) had previously completed at least one course of oral antibiotics. Thirteen of 17 (76%) had previously undergone operative irrigation and debridement of the wounds; six of 17 (35%) had previously undergone revascularization procedures of the involved extremity. Five of 17 (29%) had wounds necessitating an amputation procedure prior to the present treatment; seven of 17 (41%) had failed treatment with local growth factors prior to the present treatment. Average length of treatment with the VAC device was 8.2 weeks. Fourteen of 17 (82%) wounds successfully healed; four underwent split-thickness skin grafting for wound closure; four were briefly treated with local growth factors; six were treated with only dressing changes following VAC treatment. Three of 17 (18%) wounds failed VAC treatment; all three patients had diabetes and had wounds located in the midfoot or forefoot; two of three had severe peripheral vascular disease. Our results indicate that the Vacuum Assisted Closure negative pressure technique is emerging as an acceptable option for wound care of the lower extremity. Not all patients are candidates for such treatment; those patients with severe peripheral vascular disease or smaller forefoot wounds may be best treated by other modalities. Larger wounds seem to be better suited for skin grafting or two-stage primary

  20. Apical negative pressure irrigation versus syringe irrigation: a systematic review of cleaning and disinfection of the root canal system.

    Science.gov (United States)

    Konstantinidi, E; Psimma, Z; Chávez de Paz, L E; Boutsioukis, C

    2017-11-01

    The aim of this study was to systematically review and critically analyse the published data on the treatment outcome (primary outcome) and on the cleaning and disinfection of root canals (secondary outcomes) achieved by negative pressure irrigation as compared to syringe irrigation. An electronic search was conducted in EMBASE, LILACS, PubMed, SciELO, Scopus and Web of Knowledge using both free-text keywords and controlled vocabulary. Additional studies were sought through hand searching of endodontic journals and of the relevant chapters of endodontic textbooks. No language restriction was imposed. The retrieved studies were screened by two reviewers according to predefined criteria. Included studies were critically appraised and the extracted data were arranged in tables. The electronic search and hand search retrieved 489 titles. One clinical study and 14 in vitro studies were finally included in the review; none of these studies assessed treatment outcome, four studies assessed the antimicrobial effect, seven studies evaluated the removal of pulp tissue remnants, and four studies investigated the removal of hard tissue debris or both hard tissue debris and pulp tissue remnants. Poor standardization and description of the protocols was evident. Inconclusive results were reported about the cleaning and disinfection accomplished by the two irrigation methods. Negative pressure irrigation was more effective under certain conditions when compared to suboptimal syringe irrigation; however, the variability of the protocols hindered quantitative synthesis. There is insufficient evidence to claim general superiority of any one of these methods. The level of the available evidence is low, and the conclusions should be interpreted with caution. © 2016 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  1. Experimental evidence for negative turgor pressure in small leaf cells of Robinia pseudoacacia L versus large cells of Metasequoia glyptostroboides Hu et W.C.Cheng. 1. Evidence from pressure-volume curve analysis of dead tissue.

    Science.gov (United States)

    Yang, Dongmei; Pan, Shaoan; Ding, Yiting; Tyree, Melvin T

    2017-03-01

    This paper provides a mini-review of evidence for negative turgor pressure in leaf cells starting with experimental evidence in the late 1950s and ending with biomechanical models published in 2014. In the present study, biomechanical models were used to predict how negative turgor pressure might be manifested in dead tissue, and experiments were conducted to test the predictions. The main findings were as follows: (i) Tissues killed by heating to 60 or 80 °C or by freezing in liquid nitrogen all became equally leaky to cell sap solutes and all seemed to pass freely through the cell walls. (ii) Once cell sap solutes could freely pass the cell walls, the shape of pressure-volume curves was dramatically altered between living and dead cells. (iii) Pressure-volume curves of dead tissue seem to measure negative turgor defined as negative when inside minus outside pressure is negative. (iv) Robinia pseudoacacia leaves with small palisade cells had more negative turgor than Metasequoia glyptostroboides with large cells. (v) The absolute difference in negative turgor between R. pseudoacacia and M. glyptostroboides approached as much as 1.0 MPa in some cases. The differences in the manifestation of negative turgor in living versus dead tissue are discussed. © 2016 John Wiley & Sons Ltd.

  2. The effect of blood volume loss on cardiovascular response to lower body negative pressure using a mathematical model

    Science.gov (United States)

    Karam, E. H.; Srinivasan, R. S.; Charles, J. B.; Fortney, S. M.

    1994-01-01

    Different mathematical models of varying complexity have been proposed in recent years to study the cardiovascular (CV) system. However, only a few of them specifically address the response to lower body negative pressure (LBNP), a stress that can be applied in weightlessness to predict changes in orthostatic tolerance. Also, the simulated results produced by these models agree only partially with experimental observations. In contrast, the model proposed by Melchior et al., and modified by Karam et al. is a simple representation of the CV system capable of accurately reproducing observed LBNP responses up to presyncopal levels. There are significant changes in LBNP response due to a loss of blood volume and other alterations that occur in weightlessness and related one-g conditions such as bedrest. A few days of bedrest can cause up to 15% blood volume loss (BVL), with consequent decreases in both stroke volume and cardiac output, and increases in heart rate, mean arterial pressure, and total peripheral resistance. These changes are more pronounced at higher levels of LBNP. This paper presents the results of a simulation study using our CV model to examine the effect of BVL on LBNP response.

  3. Origin of superconductivity in KFe2As2 under positive and negative pressures and relation to other Fe-based families

    Science.gov (United States)

    Valenti, Roser

    KFe2As2 shows an intricate behavior as a function of pressure. At ambient pressure the system is superconductor with a low critical temperature Tc=3.4 K and follows a V-shaped pressure dependence of Tc for moderate pressures with a local minimum at a pressure of 1.5 GPa. Under high pressures Pc=15 GPa, KFe2As2 exhibits a structural phase transition from a tetragonal to a collapsed tetragonal phase accompanied by a boost of the superconducting critical temperature up to 12 K. On the other hand, negative pressures realized through substitution of K by Cs or Rb decrease Tc down to 2.25K. In this talk we will discuss recent progress on the understanding of the microscopic origin of this pressure-dependent behavior by considering a combination of ab initio density functional theory with dynamical mean field theory and spin fluctuation theory calculations. We will argue that a Lifshitz transition associated with the structural collapse changes the pairing symmetry from d-wave (tetragonal) to s+/- (collapsed tetragonal) at high pressures while at ambient and negative pressures correlation effects appear to be detrimental for superconductivity. Further, we shall establish cross-links to the chalcogenide family, in particular FeSe under pressure. The Deutsche Forschungsgemeinschaft (DFG) is gratefully acknowledged for financial support.

  4. Treadmill exercise does not change gene expression of adrenal catecholamine biosynthetic enzymes in chronically stressed rats

    Directory of Open Access Journals (Sweden)

    LJUBICA GAVRILOVIC

    2013-09-01

    Full Text Available ABSTRACT Chronic isolation of adult animals represents a form of psychological stress that produces sympatho-adrenomedullar activation. Exercise training acts as an important modulator of sympatho-adrenomedullary system. This study aimed to investigate physical exercise-related changes in gene expression of catecholamine biosynthetic enzymes (tyrosine hydroxylase, dopamine-ß-hydroxylase and phenylethanolamine N-methyltransferase and cyclic adenosine monophosphate response element-binding (CREB in the adrenal medulla, concentrations of catecholamines and corticosterone (CORT in the plasma and the weight of adrenal glands of chronically psychosocially stressed adult rats exposed daily to 20 min treadmill running for 12 weeks. Also, we examined how additional acute immobilization stress changes the mentioned parameters. Treadmill running did not result in modulation of gene expression of catecholamine synthesizing enzymes and it decreased the level of CREB mRNA in the adrenal medulla of chronically psychosocially stressed adult rats. The potentially negative physiological adaptations after treadmill running were recorded as increased concentrations of catecholamines and decreased morning CORT concentration in the plasma, as well as the adrenal gland hypertrophy of chronically psychosocially stressed rats. The additional acute immobilization stress increases gene expression of catecholamine biosynthetic enzymes in the adrenal medulla, as well as catecholamines and CORT levels in the plasma. Treadmill exercise does not change the activity of sympatho-adrenomedullary system of chronically psychosocially stressed rats.

  5. Global model analysis of negative ion generation in low-pressure inductively coupled hydrogen plasmas with bi-Maxwellian electron energy distributions

    International Nuclear Information System (INIS)

    Huh, Sung-Ryul; Kim, Nam-Kyun; Jung, Bong-Ki; Chung, Kyoung-Jae; Hwang, Yong-Seok; Kim, Gon-Ho

    2015-01-01

    A global model was developed to investigate the densities of negative ions and the other species in a low-pressure inductively coupled hydrogen plasma with a bi-Maxwellian electron energy distribution. Compared to a Maxwellian plasma, bi-Maxwellian plasmas have higher populations of low-energy electrons and highly vibrationally excited hydrogen molecules that are generated efficiently by high-energy electrons. This leads to a higher reaction rate of the dissociative electron attachment responsible for negative ion production. The model indicated that the bi-Maxwellian electron energy distribution at low pressures is favorable for the creation of negative ions. In addition, the electron temperature, electron density, and negative ion density calculated using the model were compared with the experimental data. In the low-pressure regime, the model results of the bi-Maxwellian electron energy distributions agreed well quantitatively with the experimental measurements, unlike those of the assumed Maxwellian electron energy distributions that had discrepancies

  6. Mini-Treadmill for Musculoskeletal Health, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — ZIN Technologies, Inc. proposes a novel Miniature Treadmill with resistive exercise capability for use in spaceflight exercise countermeasures and broad terrestrial...

  7. Mini-Treadmill for Musculoskeletal Health, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — ZIN Technologies, Inc. is developing a novel Miniature Treadmill with resistive exercise capability for use in spaceflight exercise countermeasures and broad...

  8. Underwater Treadmill Exercise in Adults with Osteoarthritis

    OpenAIRE

    Walker, Kristin; Walker, Cade

    2014-01-01

    The purpose of this study was to quantify the efficacy of a six-week aquatic treadmill exercise program on measures of pain, balance, mobility, and muscle thickness. We received the URCO grant for research. Three participants (age = 64.5 – 10.2) with knee OA completed a six-week exercise training intervention. Outcome measures, collected before (pre) and after (post) the six-week intervention, included visual analog scales for pain, posturography for balance, a 10 m walk test for mobility, an...

  9. Evaluation of negative-pressure wound therapy for patients with diabetic foot ulcers: systematic review and meta-analysis

    Directory of Open Access Journals (Sweden)

    Liu S

    2017-04-01

    Full Text Available Si Liu,1 Chao-zhu He,1 Yan-ting Cai,1 Qiu-ping Xing,1 Ying-zhen Guo,1 Zhi-long Chen,1 Ji-liang Su,1 Li-ping Yang2 1School of Nursing, Nanchang University, 2Department of Endocrinology, The Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China Objectives: The aim of this study was to perform an updated systematic review and meta-analysis to assess the clinical efficacy, safety, and cost-effectiveness of negative-pressure wound therapy (NPWT in the treatment of diabetic foot ulcers (DFUs.Methods: We searched the Cochrane Library, MEDLINE, EMBASE, Ovid, and Chinese Biological Medicine databases up to June 30, 2016. We also manually searched the articles from reference lists of the retrieved articles, which used the NPWT system in studies of vacuum-assisted closure therapy. Studies were identified and selected, and two independent reviewers extracted data from the studies.Results: A total of eleven randomized controlled trials, which included a total of 1,044 patients, were selected from 691 identified studies. Compared with standard dressing changes, NPWT had a higher rate of complete healing of ulcers (relative risk, 1.48; 95% confidence interval [CI]: 1.24–1.76; P<0.001, shorter healing time (mean difference, −8.07; 95% CI: −13.70–−2.45; P=0.005, greater reduction in ulcer area (mean difference, 12.18; 95% CI: 8.50–15.86; P<0.00001, greater reduction in ulcer depth (mean difference, 40.82; 95% CI: 35.97–45.67; P<0.00001, fewer amputations (relative risk, 0.31; 95% CI: 0.15–0.62; P=0.001, and no effect on the incidence of treatment-related adverse effects (relative risk, 1.12; 95% CI: 0.66–1.89; P=0.68. Meanwhile, many analyses showed that the NPWT was more cost-effective than standard dressing changes.Conclusion: These results indicate that NPWT is efficacious, safe, and cost-effective in treating DFUs. Keywords: diabetic foot ulcers, negative-pressure wound therapy, complete wound closure, amputation, meta

  10. RESTING SYMPATHETIC BAROREFLEX SENSITIVITY IN SUBJECTS WITH LOW AND HIGH TOLERANCE TO CENTRAL HYPOVOLEMIA INDUCED BY LOWER BODY NEGATIVE PRESSURE

    Directory of Open Access Journals (Sweden)

    Carmen eHinojosa-Laborde

    2014-06-01

    Full Text Available Central hypovolemia elicited by orthostasis or hemorrhage triggers sympathetically-mediated baroreflex responses to maintain organ perfusion; these reflexes are less sensitive in patients with orthostatic intolerance, and during conditions of severe blood loss, may result in cardiovascular collapse (decompensatory or circulatory shock. The ability to tolerate central hypovolemia is variable and physiological factors contributing to tolerance are emerging. We tested the hypothesis that resting muscle sympathetic nerve activity (MSNA and sympathetic baroreflex sensitivity (BRS are attenuated in male and female subjects who have low tolerance (LT to central hypovolemia induced by lower body negative pressure (LBNP. MSNA and diastolic arterial pressure (DAP were recorded in 47 human subjects who subsequently underwent LBNP to tolerance (onset of presyncopal symptoms. LT subjects experienced presyncopal symptoms prior to completing LBNP of -60 mm Hg, and subjects with high tolerance (HT experienced presyncopal symptoms after completing LBNP after -60 mmHg. Contrary to our hypothesis, resting MSNA burst incidence was not different between LT and HT subjects, and was not related to time to presyncope. BRS was assessed as the slope of the relationship between spontaneous fluctuations in DAP and MSNA during 5 min of supine rest. MSNA burst incidence/DAP correlations were greater than or equal to 0.5 in 37 subjects (LT: n= 9; HT: n=28, and BRS was not different between LT and HT (-1.8 ± 0.3 vs. -2.2 ± 0.2 bursts•(100 beats-1•mmHg-1, p=0.29. We conclude that tolerance to central hypovolemia is not related to either resting MSNA or sympathetic BRS.

  11. In-flight Assessment of Lower Body Negative Pressure as a Countermeasure for Post-flight Orthostatic Intolerance

    Science.gov (United States)

    Charles, J. B.; Stenger, M. B.; Phillips, T. R.; Arzeno, N. M.; Lee, S. M. C.

    2009-01-01

    Introduction. We investigated the efficacy of combining fluid loading with sustained lower body negative pressure (LBNP) to reverse orthostatic intolerance associated with weightlessness during and immediately after Space Shuttle missions. Methods. Shuttle astronauts (n=13) underwent 4 hours of LBNP at -30 mm(Hg) and ingested water and salt ( soak treatment) during flight in two complementary studies. In the first study (n=8), pre-flight heart rate (HR) and blood pressure (BP) responses to an LBNP ramp (5-min stages of -10 mm(Hg) steps to -50 mm(Hg) were compared to responses in-flight one and two days after LBNP soak treatment. In the second study (n=5), the soak was performed 24 hr before landing, and post-flight stand test results of soak subjects were compared with those of an untreated cohort (n=7). In both studies, the soak was scheduled late in the mission and was preceded by LBNP ramp tests at approximately 3-day intervals to document the in-flight loss of orthostatic tolerance. Results. Increased HR and decreased BP responses to LBNP were evident early in-flight. In-flight, one day after LBNP soak, HR and BP responses to LBNP were not different from pre-flight, but the effect was absent the second day after treatment. Post-flight there were no between-group differences in HR and BP responses to standing, but all 5 treatment subjects completed the 5-minute stand test whereas 2 of 7 untreated cohort subjects did not. Discussion. Exaggerated HR and BP responses to LBNP were evident within the first few days of space flight, extending results from Skylab. The combined LBNP and fluid ingestion countermeasure restored in-flight LBNP HR and BP responses to pre-flight levels and provided protection of post-landing orthostatic function. Unfortunately, any benefits of the combined countermeasure were offset by the complexity of its implementation, making it inappropriate for routine application during Shuttle flights.

  12. Treatment of hardware infection after osteosynthesis of lower leg using negative pressure wound therapy and transforming powder dressing.

    Science.gov (United States)

    Marinović, Marin; Ivandcić, Aldo; Spanjol, Josip; Pina, Maja; Bakota, Bore; Bandalović, Ante; Cukeljs, Fabijan

    2014-12-01

    Fractures of the distal part of the lower leg are more common in everyday practice and traumatology. In young and active patients these injuries are mainly caused by high energy trauma. They are treated with external fixator in first step, and in second step, after sanation of the soft tissue, with open reduction and internal fixation (ORIF). It is very safe and effective method of treatment. Treatment of the infections that occur in the early postoperative period after open reduction and internal fixation represents a great problem and challenge for surgeons. It is widely accepted that the presence of deep infection can't be cured in the presence of hardware. However, removal of hardware in the presence of unhealed fractures significantly complicates sanation of infection and fracture itself We have decided to present a 35-years-old patient with a hardware infection with present chronic wound with hardware exposed eight months after the first operation and six months after second operation. The wound measured one centimeter in diameter with cell detritus and bad granulations tissue inside the wound. Hardwre was exposed in the depth of the wound.The secretion was minimal. Negative Pressure Wound Therapy (NPWT) was applicated after debridemet and lavage performed in ambulatory conditions. The starting therapy was continuously -125 mm Hg of vacuum. After five days of NPWT the defect was partially filled with granula- tion tissue. For another five days we continue with NPWT with the same values of-125 mm Hg pressure but in the inter- mitent mode. After that period we used transforming powder dressing for covering and protection of the wound with was filled with granulation tissue. Five days later, wound was completely healed with epithelisation. After four months of patient follow-up, we found the wound is completely repaired. The patient denies pain and has continued orderly flow of fracture healing, with no signs of infection.

  13. Oxygen Consumption of Elite Distance Runners on an Anti-Gravity Treadmill®

    Directory of Open Access Journals (Sweden)

    David K.P. McNeill, John R. Kline, Hendrick D. de Heer, J. Richard Coast

    2015-06-01

    Full Text Available Lower body positive pressure (LBPP, or ‘anti-gravity’ treadmills® have become increasingly popular among elite distance runners. However, to date, few studies have assessed the effect of body weight support (BWS on the metabolic cost of running among elite runners. This study evaluated how BWS influenced the relationship between velocity and metabolic cost among 6 elite male distance runners. Participants ran three- 16 minute tests consisting of 4 stages of 4 minutes at 8, 7, 6 and 5 min·mile−1 pace (3.35, 3.84, 4.47 and 5.36 m·s−1, while maintaining an aerobic effort (Respiratory Exchange Ratio ≤1.00. One test was run on a regular treadmill, one on an anti-gravity treadmill with 40% BWS and one with 20% BWS being provided. Expired gas data were collected and regression equations used to determine and compare slopes. Significant decreases in oxygen uptake (V̇O2 were found with each increase in BWS (p < 0.001. At 20% BWS, the average decrease in net VO2 was greater than proportional (34%, while at 40% BWS, the average net reduction in VO2 was close to proportional (38%. Across velocities, the slope of the relationship between VO2 and velocity (ΔV̇O2/Δv was steeper with less support. The slopes at both the 20% and 40% BWS conditions were similar, especially when compared to the regular treadmill. Variability in VO2 between athletes was much greater on the LBPP treadmill and was greater with increased levels of BWS. In this study we evaluated the effect of body weight support on V̇O2 among elite distance runners. We have shown that oxygen uptake decreased with support, but not in direct proportion to that support. Further, because of the high variability in oxygen uptake between athletes on the LBPP treadmill, prediction equations may not be reliable and other indicators (heart rate, perceived exertion or directly measured oxygen uptake should be used to guide training intensity when training on the LBPP treadmill.

  14. Role of different negative pressure values in the process of infected wounds treated by vacuum-assisted closure: an experimental study.

    Science.gov (United States)

    Zhou, Min; Yu, Aixi; Wu, Gang; Xia, Chengyan; Hu, Xiang; Qi, Baiwen

    2013-10-01

    Vacuum-assisted closure (VAC) device is widely used to treat infected wounds in clinical work. Although the effect of VAC with different negative pressure values is well established, whether different negative pressures could result in varying modulation of wound relative cytokines was not clear. We hypothesise that instead of the highest negative pressure value the suitable value for VAC is the one which is the most effective on regulating wound relative cytokines. Infected wounds created on pigs' back were used to investigate the effects of varying negative pressure values of VAC devices. Wounds were treated with VAC of different negative pressure values or moist gauze, which was set as control. The VAC foam, semiocclusive dresses and moist gauze were changed on days 3, 5, 7 and 9 after wounds were created. When changing dressings, tissues from wounds were harvested for bacteria count and histology examination including Masson's trichrome stain and immunohistochemistry for microvessels. Western blot was carried out to test the expression of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF). Results showed that on days 3 and 5 the number of bacteria in wounds treated by VAC with 75, 150, 225 and 300 mmHg was significantly decreased compared with that in wounds treated by gauze and 0 mmHg pressure value. However, there was no difference in wounds treated with negative pressure values of 75 , 150, 225 and 300 mmHg at any time spot. Immunohistochemistry showed that more microvessels were generated in wounds treated by VAC using 75 and 150 mmHg negative pressure comparing with that using 225 and 300 mmHg on days 3 and 5. However this difference vanished on days 7 and 9. Morphological evaluation by Masson's trichrome staining showed increased collagen deposition in VAC of 75 and 150 mmHg compared with that in VAC of 225 and 300 mmHg. Western blot showed that the expression of VEGF and bFGF significantly increased when the wounds

  15. Psychomotor performance during a 28 day head-down tilt with and without lower body negative pressure

    Science.gov (United States)

    Traon, A. Pavy-le; de Feneyrols, A. Rous; Cornac, A.; Abdeseelam, R.; N'uygen, D.; Lazerges, M.; Güell, A.; Bes, A.

    Several factors may affect psychomotor performance in space: sensory-motor changes, sleep disturbances, psychological modifications induced by the social isolation and confinement. However, psychomotor performance is difficult to assess. A battery of standardized and computerized tests, so-called "Automated Portable Test System" (APTS) was devised to ascertain the cognitive, perceptive and motor abilities and their possible fluctuations according to environmental effects. Antiorthostatic bedrest, often used to simulate weightlessness, (particularly cardiovascular modifications) also constitutes a situation of social confinement and isolation. During two bedrest experiments (with head-down tilt of -6°) of 28 days each, we intended to assess psychomotor performance of 6 males so as to determine whether: —on the one hand, it could be altered by remaining in decubitus; —on the other, the Lower Body Negative Pressure sessions, designed to prevent orthostatic intolerance back on Earth, could improve the performance. To accomplish this, part of the APTS tests as well as an automated perceptive attention test were performed. No downgrading of psychomotor performance was observed. On the contrary, the tasks were more accurately performed over time. In order to assess the experimental conditions on the acquisition phase, the learning curves were modelled. A beneficial effect of the LBNP sessions on simple tests involving the visual-motor coordination and attention faculties can only be regarded as a mere trend. Methods used in this experiment are also discussed.

  16. Negative pressure driven valence instability of Eu in cubic Eu0.4La0.6Pd3

    International Nuclear Information System (INIS)

    Pandey, Abhishek; Mazumdar, Chandan; Ranganathan, R

    2009-01-01

    We report the change in the valency of Eu-ions in the binary intermetallic cubic compound EuPd 3 induced by La doping at rare-earth sites. Doping of La generates negative chemical pressure in the lattice, resulting in a significant increase of the lattice parameter without altering the simple-cubic structure of the compound. Results of dc-magnetic measurements suggest that this increase in the lattice parameter is associated with the valence transition of Eu-ions from Eu 3+ to a mixed-valent state. As Eu 2+ -ions possess a large magnetic moment, this valence transition significantly modifies the magnetic behavior of the compound. In contrast to introducing boron at the vacant body center site of the unit cell to change the valency of Eu-ions, as in the case of EuPd 3 B, our results suggest it can also be altered by doping a rare-earth ion of larger size at the lattice site of Eu in EuPd 3 .

  17. Working in a danger zone: A qualitative study of Taiwanese nurses' work experiences in a negative pressure isolation ward.

    Science.gov (United States)

    Chen, Shu-Ling; Chen, Kuei-Ling; Lee, Li-Hung; Yang, Cheng-I

    2016-07-01

    Hospital nurses are frontline health care workers in controlling the spread of infectious diseases. It is not known if nurses working in negative pressure isolation wards (NPIWs) are better prepared than before to safely care for patients with common infectious diseases. For this qualitative descriptive study, 10 nurses were interviewed in depth about their experiences caring for patients in an NPIW. Tape recordings were transcribed verbatim and analyzed by qualitative content analysis. The following 5 themes were identified: (1) complexity of patient care, (2) dissatisfaction with the quantity and quality of protective equipment, (3) shortage of nursing staff, (4) continued worries about being infected, and (5) sensitivity to self-protection. Our participants' anxiety and uncertainty about being infected in the NPIW were increased by the complexity of patients' health problems and organizational factors. To protect themselves against infection before and during patient care, participants also developed sensitivity to, concepts about, and strategies to improve self-protection. NPIW administrators should pay more attention to nurses' concerns about improving the NPIW working environment, supply good quality protective equipment, and provide appropriate psychologic support and ongoing education to ensure that nurses feel safe while working. This ongoing education should refresh and update nurses' knowledge about disease transmission, therefore decreasing unnecessary anxiety based on misunderstandings about becoming infected. Copyright © 2016 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  18. Negative pressure wound therapy using polyvinyl alcohol foam to bolster full-thickness mesh skin grafts in dogs.

    Science.gov (United States)

    Or, Matan; Van Goethem, Bart; Kitshoff, Adriaan; Koenraadt, Annika; Schwarzkopf, Ilona; Bosmans, Tim; de Rooster, Hilde

    2017-04-01

    To report the use of negative pressure wound therapy (NPWT) with polyvinyl alcohol (PVA) foam to bolster full-thickness mesh skin grafts in dogs. Retrospective case series. Client-owned dogs (n = 8). Full-thickness mesh skin graft was directly covered with PVA foam. NPWT was maintained for 5 days (in 1 or 2 cycles). Grafts were evaluated on days 2, 5, 10, 15, and 30 for graft appearance and graft take, granulation tissue formation, and complications. Firm attachment of the graft to the recipient bed was accomplished in 7 dogs with granulation tissue quickly filling the mesh holes, and graft take considered excellent. One dog had bandage complications after cessation of the NPWT, causing partial graft loss. The PVA foam did not adhere to the graft or damage the surrounding skin. The application of NPWT with a PVA foam after full-thickness mesh skin grafting in dogs provides an effective method for securing skin grafts, with good graft acceptance. PVA foam can be used as a primary dressing for skin grafts, obviating the need for other interposing materials to protect the graft and the surrounding skin. © 2017 The American College of Veterinary Surgeons.

  19. Coverage of Deep Cutaneous Wounds Using Dermal Template in Combination with Negative-pressure Therapy and Subsequent Skin Graft

    Science.gov (United States)

    Chang, Alexandre A.; Lobato, Rodolfo C.; Nakamoto, Hugo A.; Tuma, Paulo; Ferreira, Marcus C.

    2014-01-01

    Background: We consider the use of dermal matrix associated with a skin graft to cover deep wounds in the extremities when tendon and bone are exposed. The objective of this article was to evaluate the efficacy of covering acute deep wounds through the use of a dermal regeneration template (Integra) associated with vacuum therapy and subsequent skin grafting. Methods: Twenty patients were evaluated prospectively. All of them had acute (up to 3 weeks) deep wounds in the limbs. We consider a deep wound to be that with exposure of bone, tendon, or joint. Results: The average area of integration of the dermal regeneration template was 86.5%. There was complete integration of the skin graft over the dermal matrix in 14 patients (70%), partial integration in 5 patients (25%), and total loss in 1 case (5%). The wound has completely closed in 95% of patients. Conclusions: The use of Integra dermal template associated with negative-pressure therapy and skin grafting showed an adequate rate of resolution of deep wounds with low morbidity. PMID:25289363

  20. Negative Pressure Wound Therapy Applied Before and After Split-Thickness Skin Graft Helps Healing of Fournier Gangrene

    Science.gov (United States)

    Ye, Junna; Xie, Ting; Wu, Minjie; Ni, Pengwen; Lu, Shuliang

    2015-01-01

    Abstract Fournier gangrene is a rare but highly infectious disease characterized by fulminant necrotizing fasciitis involving the genital and perineal regions. Negative pressure wound therapy (NPWT; KCI USA Inc, San Antonio, TX) is a widely adopted technique in many clinical settings. Nevertheless, its application and effect in the treatment of Fournier gangrene are unclear. A 47-year-old male patient was admitted with an anal abscess followed by a spread of the infection to the scrotum, which was caused by Pseudomonas aeruginosa. NPWT was applied on the surface of the scrotal area and continued for 10 days. A split-thickness skin graft from the scalp was then grafted to the wound, after which, NPWT utilizing gauze sealed with an occlusive dressing and connected to a wall suction was employed for 7 days to secure the skin graft. At discharge, the percentage of the grafted skin alive on the scrotum was 98%. The wound beside the anus had decreased to 4 × 0.5 cm with a depth of 1 cm. Follow-up at the clinic 1 month later showed that both wounds had healed. The patient did not complain of any pain or bleeding, and was satisfied with the outcome. NPWT before and after split-thickness skin grafts is safe, well tolerated, and efficacious in the treatment of Fournier gangrene. PMID:25654376

  1. Anomalous thermal expansion, negative linear compressibility, and high-pressure phase transition in ZnAu2(CN) 4 : Neutron inelastic scattering and lattice dynamics studies

    Science.gov (United States)

    Gupta, Mayanak K.; Singh, Baltej; Mittal, Ranjan; Zbiri, Mohamed; Cairns, Andrew B.; Goodwin, Andrew L.; Schober, Helmut; Chaplot, Samrath L.

    2017-12-01

    We present temperature-dependent inelastic-neutron-scattering measurements, accompanied by ab initio calculations of the phonon spectra and elastic properties as a function of pressure to quantitatively explain an unusual combination of negative thermal expansion and negative linear compressibility behavior of ZnAu2(CN) 4 . The mechanism of the negative thermal expansion is identified in terms of specific anharmonic phonon modes that involve bending of the -Zn-NC-Au-CN-Zn- linkage. The soft phonon at the L point at the Brillouin zone boundary quantitatively relates to the high-pressure phase transition at about 2 GPa. The ambient pressure structure is also found to be close to an elastic instability that leads to a weakly first-order transition.

  2. Use of negative-pressure dressings and split-thickness skin grafts following penile shaft reduction and reduction scrotoplasty in the management of penoscrotal elephantiasis.

    Science.gov (United States)

    Stokes, Tracey H; Follmar, Keith E; Silverstein, Ari D; Weizer, Alon Z; Donatucci, Craig F; Anderson, Everett E; Erdmann, Detlev

    2006-06-01

    From 1988 to 2005, 8 men who presented with penoscrotal elephantiasis underwent penile shaft degloving and reduction scrotoplasty, followed by transplantation of a split-thickness skin graft (STSG) to the penile shaft. The etiology of elephantiasis in these patients included self-injection of viscous fluid and postsurgical obstructive lymphedema. In the 6 most recent cases, negative-pressure dressings were applied over the STSG to promote graft take, and STSG take rate was 100%. The results of our series corroborate those of a previous report, which showed circumferential negative-pressure dressings to be safe and efficacious in bolstering STSGs to the penile shaft. Furthermore, these results suggest that the use of negative-pressure dressings may improve graft take in this patient population.

  3. How bacterial cell division might cheat turgor pressure - a unified mechanism of septal division in Gram-positive and Gram-negative bacteria.

    Science.gov (United States)

    Erickson, Harold P

    2017-08-01

    An important question for bacterial cell division is how the invaginating septum can overcome the turgor force generated by the high osmolarity of the cytoplasm. I suggest that it may not need to. Several studies in Gram-negative bacteria have shown that the periplasm is isoosmolar with the cytoplasm. Indirect evidence suggests that this is also true for Gram-positive bacteria. In this case the invagination of the septum takes place within the uniformly high osmotic pressure environment, and does not have to fight turgor pressure. A related question is how the V-shaped constriction of Gram-negative bacteria relates to the plate-like septum of Gram-positive bacteria. I collected evidence that Gram-negative bacteria have a latent capability of forming plate-like septa, and present a model in which septal division is the basic mechanism in both Gram-positive and Gram-negative bacteria. © 2017 WILEY Periodicals, Inc.

  4. Negative pressure wound therapy via vacuum-assisted closure following partial foot amputation: what is the role of wound chronicity?

    Science.gov (United States)

    Armstrong, David G; Lavery, Lawrence A; Boulton, Andrew J M

    2007-03-01

    Randomised clinical trials (RCTs) to evaluate diabetic foot wound therapies have systematically eliminated large acute wounds from evaluation, focusing only on smaller chronic wounds. The purpose of this study was to evaluate the proportion and rate of wound healing in acute and chronic wounds after partial foot amputation in individuals with diabetes treated with negative pressure wound therapy (NPWT) delivered by the vacuum-assisted closure (VAC) device or with standard wound therapy (SWT). This study constitutes a secondary analysis of patients enrolled in a 16-week RCT of NPWT: 162 open foot amputation wounds (mean wound size = 20.7 cm(2)) were included. Acute wounds were defined as the wounds less than 30 days after amputation, whereas chronic wounds as the wounds greater than 30 days. Inclusion criteria consisted of individuals older than 18 years, presence of a diabetic foot amputation wound up to the transmetatarsal level and adequate perfusion. Wound size and healing were confirmed by independent, blinded wound evaluators. Analyses were done on an intent-to-treat basis. There was a significantly higher proportion of acute wounds (SWT = 59; NPWT = 63) than chronic wounds (SWT = 26; NPWT = 14), evaluated in this clinical trial (P = 0.001). There was no significant difference in the proportion of acute and chronic wounds achieving complete wound closure in either treatment group. Despite this finding, the Kaplan-Meier curves demonstrated statistically significantly faster healing in the NPWT group in both acute (P = 0.030) and chronic wounds (P = 0.033). Among the patients treated with NPWT via the VAC, there was not a significant difference in healing as a function of chronicity. In both the acute and the chronic wound groups, results for patients treated with NPWT were superior to those for the patients treated with SWT. These results appear to indicate that wound duration should not deter the clinician from using this modality to treat complex wounds.

  5. Negative pressure wound therapy in the management of late deep infections after open reconstruction of achilles tendon rupture.

    Science.gov (United States)

    Mosser, Philipp; Kelm, Jens; Anagnostakos, Konstantinos

    2015-01-01

    Infection is a major complication after open reconstruction of Achilles tendon ruptures. We report on the use of vacuum-assisted closure (VAC) therapy in the treatment of late deep infections after open Achilles tendon reconstruction. Six patients (5 males [83.33%], 1 female [16.67%]; mean age, 52.8 [range 37 to 66] years) were been treated using an identical protocol. Surgical management consisted of debridement, lavage, and necrectomy of infected tendon parts. The VAC therapy was used for local wound preconditioning and infection management. A continuous negative pressure of 125 mm Hg was applied on each wound. For final wound closure, a split-thickness skin graft was performed. The skin graft healing process was also supported by VAC therapy during the first 5 days. The VAC dressings were changed a mean average of 3 (range 1 to 4) times until split-thickness skin grafting could be performed. The mean total duration of the VAC therapy was 13.6 ± 5.9 days. The mean hospital stay was 31.2 ± 15.9 days. No complications with regard to bleeding, seroma, or hematoma formation beneath the skin graft were observed. At a mean follow-up duration of 29.9 (range 4 to 65) months, no re-infection or infection persistence was observed. The VAC device seems to be a valuable tool in the treatment of infected tendons. The generalization of these conclusions should await the results of future studies with larger patient series. Copyright © 2015 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  6. A comparison of two Shuttle launch and entry suits - Reach envelope, isokinetic strength, and treadmill tests

    Science.gov (United States)

    Schafer, Lauren E.; Rajulu, Sudhakar L.; Klute, Glenn K.

    1992-01-01

    A quantification has been conducted of any existing differences between the performance, in operational conditions, of the Space Shuttle crew Launch Entry Suit (LES) and the new Advanced Crew Escape Suit (ACES). While LES is a partial-pressure suit, the ACES system which is being considered as a replacement for LES is a full-pressure suit. Three tests have been conducted with six subjects to ascertain the suits' reach envelope, strength, and treadmill performance. No significant operational differences were found between the two suit designs.

  7. Angiographic and functional comparison of patients with silent and symptomatic treadmill ischemia early after myocardial infarction

    International Nuclear Information System (INIS)

    Ouyang, P.; Shapiro, E.P.; Chandra, N.C.; Gottlieb, S.H.; Chew, P.H.; Gottlieb, S.O.

    1987-01-01

    Sixty consecutive patients were studied who had positive responses to Naughton exercise treadmill testing (at least 1.5 mm of ST-segment shift in at least 2 leads or thallium reperfusion abnormalities) with or without symptoms of angina 11 +/- 1 days after acute myocardial infarction (AMI). All patients had undergone coronary angiography 24 +/- 4 days after infarction. Thirty-eight patients (63%) had no treadmill angina (silent ischemia, group I) and 22 patients had typical treadmill angina (symptomatic ischemia, group II). Use of beta-blocking drugs, calcium antagonists and nitrates at the time of exercise testing did not differ in the 2 groups. All 9 patients with diabetes mellitus were in the asymptomatic group (p less than 0.40) and group I had a greater proportion of inferior wall AMI (30 of 38) than group II (11 of 22, p = 0.02). Total exercise treadmill test duration (group I 422 +/- 31 seconds, group II 400 +/- 46 seconds) and rate-pressure product were not different in the 2 groups. The number of patients unable to exercise 5 minutes (12 in group I and 7 in group II), the number with diffuse electrocardiographic changes (9 in group I and 7 in group II), and the number with inadequate blood pressure response (8 in group I and 4 in group II) were also similar. At coronary arteriography the mean number of arteries with at least 70% diameter stenosis was 2.0 +/- 0.2 in group I and 2.2 +/- 0.2 in group II (difference not significant)

  8. A compare between myocardial topical negative pressure levels of -25 mmHg and -50 mmHg in a porcine model

    DEFF Research Database (Denmark)

    Lindstedt, Sandra; Paulsson, Per; Mokhtari, Arash

    2008-01-01

    Topical negative pressure (TNP), widely used in wound therapy, is known to stimulate wound edge blood flow, granulation tissue formation, angiogenesis, and revascularization. We have previously shown that application of a TNP of -50 mmHg to the myocardium significantly increases microvascular blo...

  9. Major bleeding during negative pressure wound/V.A.C.®--therapy for postsurgical deep sternal wound infection--a critical appraisal

    NARCIS (Netherlands)

    van Wingerden, Jan J.; Segers, Patrique; Jekel, Lilian

    2011-01-01

    Negative-pressure wound therapy, commercially known as vacuum-assisted closure (V.A.C.®) therapy, has become one of the most popular (and efficacious) interim (prior to flap reconstruction) or definite methods of managing deep sternal wound infection. Complications such as profuse bleeding, which

  10. Negative pressure of the environmental air in the cleaning area of the materials and sterilization center: a systematic review.

    Science.gov (United States)

    Ciofi-Silva, Caroline Lopes; Hansen, Lisbeth Lima; Almeida, Alda Graciele Claudio Dos Santos; Kawagoe, Julia Yaeko; Padoveze, Maria Clara; Graziano, Kazuko Uchikawa

    2016-09-01

    to analyze the scientific evidence on aerosols generated during cleaning activities of health products in the Central Service Department (CSD) and the impact of the negative pressure of the ambient air in the cleaning area to control the dispersion of aerosols to adjacent areas. for this literature systematic review the following searches were done: search guidelines, manuals or national and international technical standards given by experts; search in the portal and databases PubMed, Scopus, CINAHL and Web of Science; and a manual search of scientific articles. the five technical documents reviewed recommend that the CSD cleaning area should have a negative differential ambient air pressure, but scientific articles on the impact of this intervention were not found. The four articles included talked about aerosols formed after the use of a ultrasonic cleaner (an increased in the contamination especially during use) and pressurized water jet (formation of smaller aerosols 5μm). In a study, the aerosols formed from contaminated the hot tap water with Legionella pneumophila were evaluated. there is evidence of aerosol formation during cleanup activities in CSD. Studies on occupational diseases of respiratory origin of workers who work in CSD should be performed. analisar as evidências científicas sobre aerossóis gerados durante atividades de limpeza dos produtos para saúde no Centro de Material e Esterilização (CME) e o impacto da pressão negativa do ar ambiente na área de limpeza para controle da dispersão de aerossóis para áreas adjacentes. para essa revisão sistemática de literatura foram realizadas: busca de diretrizes, manuais ou normas técnicas nacionais e internacionais indicadas por especialistas; busca no portal e bases de dados PUBMED, SCOPUS, Cinahl e Web of Science; e busca manual de artigos científicos. Os cinco documentos técnicos analisados preconizam que na área de limpeza do CME haja diferencial negativo de pressão do ar ambiente

  11. Effect of the treadmill training factors on the locomotor ability after space flight

    Science.gov (United States)

    Lysova, Nataliya; Fomina, Elena

    Training on the treadmill constitutes the central component of the Russian system of countermeasures against the negative effects of microgravity. Effectiveness of the treadmill training is influenced by three main factors. Namely, these are intensity (velocity and regularity), axial loading with the use of elastic bungee cords and percentage of time for training on the non-motorized treadmill within the overall training program. Previously we have demonstrated the significance of each factor separately: intensity (Kozlovskaya I.B. et al., 2011), passive mode (Fomina E.V. et al., 2012) and axial loading (Fomina E.V. et al., 2013). The Russian system of in-flight countermeasures gives preference to interval training sessions in which walking alternates with short episodes of intensive running. Locomotion on the non-motorized treadmill should make approx. 30% of the total time of locomotor training. The ISS RS treadmill can be utilized with the motor in motion (active mode) or out of motion so that the cosmonaut has to push the belt with his feet (passive mode). Axial loading of the cosmonaut must be 60-70% of his body weight. However, there is a huge variety of strategies cosmonauts choose of when they exercise on the treadmill in the course of long-duration ISS missions. Purpose of the investigation was comparative analysis of different locomotion training regimens from the standpoint of their effectiveness in microgravity. Criteria of effectiveness evaluation were the results of the locomotion test that includes walking along the fixed support at the preset rate of 90 steps/min. Peak amplitude on the m. soleus electromyogram was analyzed. The experiment was performed with participation of 18 Russian members of extended ISS missions. Each locomotion training factors was rated using the score scale from 0 to 10: Intensity (0 to 10), Percentage of passive mode training (recommended 30% was taken as 10 and could go down to 0 if the passive mode was not applied) and

  12. Economic and organizational sustainability of a negative-pressure portable device for the prevention of surgical-site complications

    Directory of Open Access Journals (Sweden)

    Foglia E

    2017-06-01

    Full Text Available Emanuela Foglia,1 Lucrezia Ferrario,1 Elisabetta Garagiola,1 Giuseppe Signoriello,2 Gianluca Pellino,3 Davide Croce,1,4 Silvestro Canonico3 1Centre for Health Economics, Social and Health Care Management - LIUC University, Castellanza, Italy; 2Department of Mental Health and Preventive Medicine, University of Campania “Luigi Vanvitelli”, Naples, Italy; 3School of Medicine, University of Campania “Luigi Vanvitelli”, Naples, Italy; 4School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South \tAfrica Purpose: Surgical-site complications (SSCs affect patients’ clinical pathway, prolonging their hospitalization and incrementing their management costs. The present study aimed to assess the economic and organizational implications of a portable device for negative-pressure wound therapy (NPWT implementation, compared with the administration of pharmacological therapies alone for preventing surgical complications in patients undergoing general, cardiac, obstetrical–gynecological, or orthopedic surgical procedures.Patients and methods: A total of 8,566 hospital procedures, related to the year 2015 from one hospital, were evaluated considering infection risk index, occurrence rates of SSCs, drug therapies, and surgical, diagnostic, and specialist procedures and hematological exams. Activity-based costing and budget impact analyses were implemented for the economic assessment.Results: Patients developing an SSC absorbed i 64.27% more economic resources considering the length of stay (€ 8,269±2,096 versus € 5,034±2,901, p<0.05 and ii 42.43% more economic resources related to hematological and diagnostic procedures (€ 639±117 versus € 449±72, p<0.05. If the innovative device had been used over the 12-month time period, it would have decreased the risk of developing SSCs; the hospital would have realized an average reduction in health care expenditure equal to −0.69% (−€ 483

  13. [Can Topical Negative Pressure Therapy be Performed as a Cost-Effective General Surgery Procedure in the German DRG System?].

    Science.gov (United States)

    Hirche, Z; Xiong, L; Hirche, C; Willis, S

    2016-04-01

    Topical negative pressure therapy (TNPT) has been established for surgical wound therapy with different indications. Nevertheless, there is only sparse evidence regarding its therapeutic superiority or cost-effectiveness in the German DRG system (G-DRG). This study was designed to analyse the cost-effectiveness of TNPT in the G-DRG system with a focus on daily treatment costs and reimbursement in a general surgery care setting. In this retrospective study, we included 176 patients, who underwent TNPT between 2007 and 2011 for general surgery indications. Analysis of the cost-effectiveness involved 149 patients who underwent a simulation to calculate the reimbursement with or without TNPT by a virtual control group in which the TNP procedure was withdrawn for DRG calculation. This was followed by a calculation of costs for wound dressings and TNPT rent and material costs. Comparison between the "true" and the virtual group enabled calculation of the effective remaining surplus per case. Total reimbursement by included TNPT cases was 2,323 ,70.04 €. Costs for wound dressings and TNPT rent were 102,669.20 €. In 41 cases there was a cost-effectiveness (27.5%) with 607,422.03 € with TNP treatment, while the control group without TNP generated revenues of 442,015.10 €. Costs for wound dressings and TNPT rent were 47,376.68 €. In the final account we could generate a cost-effectiveness of 6759 € in 5 years per 149 patients by TNPT. In 108 cases there was no cost-effectiveness (72.5%). TNPT applied in a representative general surgery setting allows for wound therapy without a major financial burden. Based on the costs for wound dressings and TNPT rent, a primarily medically based decision when to use TNPT can be performed in a balanced product cost accounting. This study does not analyse the superiority of TNPT in wound care, so further prospective studies are required which focus on therapeutic superiority and cost-effectiveness. Georg Thieme

  14. Effects of negative pressure wound therapy on the expression of EDA+ FN in granulation tissues of human diabetic foot wounds

    Directory of Open Access Journals (Sweden)

    Shao-ling YANG

    2017-04-01

    Full Text Available Objective  To investigate the effects of negative pressure wound therapy (NPWT on the expression of EDA+ FN in granulation tissues of human diabetic foot wounds. Methods  Forty patients with diabetic foot wounds fitting the inclusion criteria, admitted from Jan. 2014 to Jun. 2016, were randomly and equally apportioned to receive either NPWT or conventional gauze therapy (control for 14 days. Granulated tissue biopsies were collected before (0 day and after (14 day treatment in both groups. All biopsies were subdivided into two parts. One part was preserved in 4% paraformaldehyde for immunocytochemical staining of EDA+ FN, and the other part was stored at –80℃for Western blotting and PCR analysis of EDA+ FN. Results  The immunohistochemical analysis revealed that the mean area density of EDA+ FN increased in both NPWT group and control group at day 14 relative to day 0, but the change value of mean area density was higher in NPWT group than in control group (P<0.01. Western blotting showed that the relative protein levels of EDA+ FN increased in both NPWT group and control group at day 14 relative to day 0, but the change value of relative protein levels of EDA+ FN was higher in NPWT group than in control group (P<0.01. The real time PCR analysis demonstrated that the relative mRNA levels of EDA+ FN increased in both NPWT group and control group at day 14 relative to day 0, but the change value of relative mRNA levels of EDA+ FN was higher in NPWT group than in control group (P<0.01. The results demonstrated the higher protein and mRNA levels of EDA+ FN in NPWT group than that in control group. Conclusion  NPWT obviously enhances EDA+ FN expression in granulation tissue of diabetic foot wound, as a result promotes wound healing. DOI: 10.11855/j.issn.0577-7402.2017.03.09

  15. A synergy perspective on gait – over-ground vs. treadmill walking

    DEFF Research Database (Denmark)

    Læssøe, Uffe; Madeleine, Pascal

    on movements has proposed that elemental and performance variables may represent good and bad components of variability [2]. We suggest that the gait pattern can be regarded as a movement synergy in which medio-lateral deviation in one stride can be corrected during the next stride (the elemental variables......). Such corrections ensure a straight gait path (the performance variable). AIM: The aim of this study was to apply a synergy approach to gait analysis by comparing over-ground and treadmill walking. The treadmill was hypothesized to demand a less variable walking path resulting in a larger good/bad variability ratio...... of the strides, and bad variance with respect to a similar line with a negative slope. The good/bad variance ratio was calculated and the difference between treadmill and over-ground walking was finally evaluated. RESULTS: The good/bad variance ratio for over-ground walking was 1.7 (CI95%: 1.5-2.0). When walking...

  16. Revascularization and periapical repair after endodontic treatment using apical negative pressure irrigation versus conventional irrigation plus triantibiotic intracanal dressing in dogs' teeth with apical periodontitis.

    Science.gov (United States)

    da Silva, Lea Assed Bezerra; Nelson-Filho, Paulo; da Silva, Raquel Assed Bezerra; Flores, Daniel Silva Herzog; Heilborn, Carlos; Johnson, James D; Cohenca, Nestor

    2010-05-01

    The objective of this study was to evaluate in vivo the revascularization and the apical and periapical repair after endodontic treatment using 2 techniques for root canal disinfection (apical negative pressure irrigation versus apical positive pressure irrigation plus triantibiotic intracanal dressing) in immature dogs' teeth with apical periodontitis. Two test groups of canals with experimentally induced apical periodontitis were evaluated according to the disinfection technique: Group 1, apical negative pressure irrigation (EndoVac system), and Group 2, apical positive pressure irrigation (conventional irrigation) plus triantibiotic intracanal dressing. In Group 3 (positive control), periapical lesions were induced, but no endodontic treatment was done. Group 4 (negative control) was composed of sound teeth. The animals were killed after 90 days and the maxillas and mandibles were subjected to histological processing. The sections were stained with hematoxylin and eosin and Mallory Trichrome and examined under light microscopy. A description of the apical and periapical features was done and scores were attributed to the following histopathological parameters: newly formed mineralized apical tissue, periapical inflammatory infiltrate, apical periodontal ligament thickness, dentin resorption, and bone tissue resorption. Intergroup comparisons were done by the Kruskal-Wallis and Dunn's tests (alpha = 0.05). Although statistically significant difference was found only for the inflammatory infiltrate (P irrigation with the EndoVac system can be considered as a promising disinfection protocol in immature teeth with apical periodontitis, suggesting that the use of intracanal antibiotics might not be necessary. Copyright (c) 2010 Mosby, Inc. All rights reserved.

  17. Oxygen consumption of elite distance runners on an anti-gravity treadmill®.

    Science.gov (United States)

    McNeill, David K P; Kline, John R; de Heer, Hendrick D; Coast, J Richard

    2015-06-01

    Lower body positive pressure (LBPP), or 'anti-gravity' treadmills® have become increasingly popular among elite distance runners. However, to date, few studies have assessed the effect of body weight support (BWS) on the metabolic cost of running among elite runners. This study evaluated how BWS influenced the relationship between velocity and metabolic cost among 6 elite male distance runners. Participants ran three- 16 minute tests consisting of 4 stages of 4 minutes at 8, 7, 6 and 5 min·mile(-1) pace (3.35, 3.84, 4.47 and 5.36 m·s(-1)), while maintaining an aerobic effort (Respiratory Exchange Ratio ≤1.00). One test was run on a regular treadmill, one on an anti-gravity treadmill with 40% BWS and one with 20% BWS being provided. Expired gas data were collected and regression equations used to determine and compare slopes. Significant decreases in oxygen uptake (V̇O2) were found with each increase in BWS (p rate, perceived exertion or directly measured oxygen uptake) should be used to guide training intensity when training on the LBPP treadmill. Key pointsWith increasing amounts of body weight-support (BWS), the slope of the relationship between velocity and oxygen consumption (ΔVO2/Δv) decreases significantly. This means the change in oxygen consumption (VO2) is significantly smaller over a given change in velocity at higher amounts of BWS.There is a non-linear decrease in VO2 with increasing BWS. As such, with each increment in the amount of BWS provided, the reduction in VO2 becomes increasingly smaller.This paper provides first of its kind data on the effects of BWS on the cost of running among highly trained, elite runners. The outcomes of this study are in line with previous findings among non-elite runners.

  18. Cracked rocks with positive and negative Poisson's ratio: real-crack properties extracted from pressure dependence of elastic-wave velocities

    Science.gov (United States)

    Zaitsev, Vladimir Y.; Radostin, Andrey V.; Dyskin, Arcady V.; Pasternak, Elena

    2017-04-01

    We report results of analysis of literature data on P- and S-wave velocities of rocks subjected to variable hydrostatic pressure. Out of about 90 examined samples, in more than 40% of the samples the reconstructed Poisson's ratios are negative for lowest confining pressure with gradual transition to the conventional positive values at higher pressure. The portion of rocks exhibiting negative Poisson's ratio appeared to be unexpectedly high. To understand the mechanism of negative Poisson's ratio, pressure dependences of P- and S-wave velocities were analyzed using the effective medium model in which the reduction in the elastic moduli due to cracks is described in terms of compliances with respect to shear and normal loading that are imparted to the rock by the presence of cracks. This is in contrast to widely used descriptions of effective cracked medium based on a specific crack model (e.g., penny-shape crack) in which the ratio between normal and shear compliances of such a crack is strictly predetermined. The analysis of pressure-dependences of the elastic wave velocities makes it possible to reveal the ratio between pure normal and shear compliances (called q-ratio below) for real defects and quantify their integral content in the rock. The examination performed demonstrates that a significant portion (over 50%) of cracks exhibit q-ratio several times higher than that assumed for the conventional penny-shape cracks. This leads to faster reduction of the Poisson's ratio with increasing the crack concentration. Samples with negative Poisson's ratio are characterized by elevated q-ratio and simultaneously crack concentration. Our results clearly indicate that the traditional crack model is not adequate for a significant portion of rocks and that the interaction between the opposite crack faces leading to domination of the normal compliance and reduced shear displacement discontinuity can play an important role in the mechanical behavior of rocks.

  19. Treadmill training with partial body weight support after stroke.

    Science.gov (United States)

    Hesse, Stefan; Werner, Cordula; von Frankenberg, Sophie; Bardeleben, Anita

    2003-02-01

    Treadmill therapy with partial BWS is a promising new approach to improve gait ability after stroke. This task-specific approach enables nonambulatory patients the repetitive practice of complex gait cycles instead of single-limb gait-preparatory maneuvers. Patients walk more symmetrically with less spasticity and better cardiovascular efficiency on the treadmill than with floor walking. Several controlled, clinical studies have shown the potential of treadmill training as a therapeutic intervention for nonambulatory patients with chronic stroke-related hemiplegia. Furthermore, controlled trials in acute stroke survivors have shown that treadmill training is as effective as other physiotherapy approaches that stress the repetitive practice of gait. Controlled multicenter trials comparing locomotor training with conventional therapy will be forthcoming. An electromechanical gait trainer that relieves the strenuous effort of the therapists and provides control of the trunk in a phase-dependent manner is a new technical alternative for gait training in severely impaired stroke patients.

  20. Treadmill walking exercise modulates bone mineral status and ...

    African Journals Online (AJOL)

    Treadmill walking exercise modulates bone mineral status and inflammatory cytokines in obese asthmatic patients with long term intake of corticosteroids. Shehab M. Abd El-Kader, Osama H. Al-Jiffri, Eman M. Ashmawy, Riziq Allah M. Gaowgzeh ...

  1. Treadmills: a preventable source of pediatric friction burn injuries.

    Science.gov (United States)

    Maguiña, Pirko; Palmieri, Tina L; Greenhalgh, David G

    2004-01-01

    Treadmills are a burn risk for children. A child's hand can get trapped in the conveyor belt, causing friction burns to the underlying tissue. The purpose of this retrospective study was to review the characteristics and treatment of treadmill-related burns in children from 1998 to 2002. Ten patients, at a mean age of 3.4 years, sustained injuries associated with treadmill use. Trapping of the hand between the conveyor belt and the base was the most frequent injury mechanism. Burn location was predominantly on fingers and palms. Four patients required operative intervention. All patients required specialized wound care as well as scar management and occupational therapy. Treadmills pose a danger to children. Current safety devices are ineffective for preventing serious hand injuries in children. New design modifications and public awareness are needed to improve child safety.

  2. Arctigenin Efficiently Enhanced Sedentary Mice Treadmill Endurance

    Science.gov (United States)

    Chen, Jing; Yu, Liang; Hu, Lihong; Jiang, Hualiang; Shen, Xu

    2011-01-01

    Physical inactivity is considered as one of the potential risk factors for the development of type 2 diabetes and other metabolic diseases, while endurance exercise training could enhance fat oxidation that is associated with insulin sensitivity improvement in obesity. AMP-activated protein kinase (AMPK) as an energy sensor plays pivotal roles in the regulation of energy homeostasis, and its activation could improve glucose uptake, promote mitochondrial biogenesis and increase glycolysis. Recent research has even suggested that AMPK activation contributed to endurance enhancement without exercise. Here we report that the natural product arctigenin from the traditional herb Arctium lappa L. (Compositae) strongly increased AMPK phosphorylation and subsequently up-regulated its downstream pathway in both H9C2 and C2C12 cells. It was discovered that arctigenin phosphorylated AMPK via calmodulin-dependent protein kinase kinase (CaMKK) and serine/threonine kinase 11(LKB1)-dependent pathways. Mice treadmill based in vivo assay further indicated that administration of arctigenin improved efficiently mice endurance as reflected by the increased fatigue time and distance, and potently enhanced mitochondrial biogenesis and fatty acid oxidation (FAO) related genes expression in muscle tissues. Our results thus suggested that arctigenin might be used as a potential lead compound for the discovery of the agents with mimic exercise training effects to treat metabolic diseases. PMID:21887385

  3. Arctigenin efficiently enhanced sedentary mice treadmill endurance.

    Directory of Open Access Journals (Sweden)

    Xuan Tang

    Full Text Available Physical inactivity is considered as one of the potential risk factors for the development of type 2 diabetes and other metabolic diseases, while endurance exercise training could enhance fat oxidation that is associated with insulin sensitivity improvement in obesity. AMP-activated protein kinase (AMPK as an energy sensor plays pivotal roles in the regulation of energy homeostasis, and its activation could improve glucose uptake, promote mitochondrial biogenesis and increase glycolysis. Recent research has even suggested that AMPK activation contributed to endurance enhancement without exercise. Here we report that the natural product arctigenin from the traditional herb Arctium lappa L. (Compositae strongly increased AMPK phosphorylation and subsequently up-regulated its downstream pathway in both H9C2 and C2C12 cells. It was discovered that arctigenin phosphorylated AMPK via calmodulin-dependent protein kinase kinase (CaMKK and serine/threonine kinase 11(LKB1-dependent pathways. Mice treadmill based in vivo assay further indicated that administration of arctigenin improved efficiently mice endurance as reflected by the increased fatigue time and distance, and potently enhanced mitochondrial biogenesis and fatty acid oxidation (FAO related genes expression in muscle tissues. Our results thus suggested that arctigenin might be used as a potential lead compound for the discovery of the agents with mimic exercise training effects to treat metabolic diseases.

  4. Graded Aerobic Treadmill Testing in Adolescent Traumatic Brain Injury Patients.

    Science.gov (United States)

    Cordingley, Dean M; Girardin, Richard; Morissette, Marc P; Reimer, Karen; Leiter, Jeff; Russell, Kelly; Ellis, Michael J

    2017-11-01

    To examine the safety and tolerability of clinical graded aerobic treadmill testing in recovering adolescent moderate and severe traumatic brain injury (TBI) patients referred to a multidisciplinary pediatric concussion program. We completed a retrospective case series of two moderate and five severe TBI patients (mean age, 17.3 years) who underwent initial Buffalo Concussion Treadmill Testing at a mean time of 71.6 days (range, 55-87) postinjury. Six patients completed one graded aerobic treadmill test each and one patient underwent initial and repeat testing. There were no complications. Five initial treadmill tests were completely tolerated and allowed an accurate assessment of exercise tolerance. Two initial tests were terminated early by the treatment team because of neurological and cardiorespiratory limitations. As a result of testing, two patients were cleared for aerobic exercise as tolerated and four patients were treated with individually tailored submaximal aerobic exercise programs resulting in subjective improvement in residual symptoms and/or exercise tolerance. Repeat treadmill testing in one patient performed after 1 month of treatment with submaximal aerobic exercise prescription was suggestive of improved exercise tolerance. One patient was able to tolerate aerobic exercise following surgery for posterior glottic stenosis. Preliminary results suggest that graded aerobic treadmill testing is a safe, well tolerated, and clinically useful tool to assess exercise tolerance in appropriately selected adolescent patients with TBI. Future prospective studies are needed to evaluate the effect of tailored submaximal aerobic exercise prescription on exercise tolerance and patient outcomes in recovering adolescent moderate and severe TBI patients.

  5. Major bleeding during negative pressure wound/V.A.C.® - therapy for postsurgical deep sternal wound infection - a critical appraisal

    Directory of Open Access Journals (Sweden)

    Segers Patrique

    2011-09-01

    Full Text Available Abstract Negative-pressure wound therapy, commercially known as vacuum-assisted closure (V.A.C.® therapy, has become one of the most popular (and efficacious interim (prior to flap reconstruction or definite methods of managing deep sternal wound infection. Complications such as profuse bleeding, which may occur during negative-pressure therapy but not necessarily due to it, are often attributed to a single factor and reported as such. However, despite the wealth of clinical experience internationally available, information regarding certain simple considerations is still lacking. Garnering information on all the factors that could possibly influence the outcome has become more difficult due to a (fortunate decrease in the incidence of deep sternal wound infection. If more insight is to be gained from fewer clinical cases, then various potentially confounding factors should be fully disclosed before complications can be attributed to the technique itself or improvements to negative-pressure wound therapy for deep sternal wound infection can be accepted as evidence-based and the guidelines for its use adapted. The authors propose the adoption of a simple checklist in such cases.

  6. Effect of negative pressure therapy on repair of soft tissues of the lower extremities in patients with neuropathic and neuroischaemic forms of diabetic foot syndrome

    Directory of Open Access Journals (Sweden)

    Ekaterina Leonidovna Zaytseva

    2014-06-01

    Full Text Available Aim. To evaluate the efficiency of topical negative pressure wound therapy (NPWT compared with standard therapy for the regeneration of the soft tissues of the lower extremities in patients with diabetic foot syndrome. Materials and Methods. The effects of negative pressure therapy on the clinical (size, tissue oxygenation, histological (light microscopy and immunohistochemical (CD68, MMP-9, TIMP-1 aspects of repair of the soft tissue of the lower extremities in patients with diabetes mellitus were compared with those of standard treatment. Thirty-one patients with diabetic foot ulcers were included in the study from the moment of debridement until the plastic closure of the wound. During the perioperative period, 13 patients received NPWT (-90 to -120 mmHg and 18 patients received standard therapy. Results. A reduction of the wound area (26.6%?17.2% and the depth of the defects (40.5%?25.6% were achieved with negative pressure therapy compared with baseline data. In the control group, the corresponding values were 25.3%?19.4% and 21.8%?21.6%, respectively. The results of transcutaneous oximetry showed a greater increase in the level of local hemodynamics in the study group (p

  7. Stability of the geometrically frustrated magnetic state of Ca3CoRhO6 to applications of positive and negative pressure

    International Nuclear Information System (INIS)

    Mohapatra, Niharika; Iyer, Kartik K; Jammalamadaka, S Narayana; Sampathkumaran, E V; Rayaprol, Sudhindra

    2008-01-01

    The influence of negative chemical pressure induced by gradual replacement of Ca by Sr as well as of external pressure (up to 10 kbar) on the magnetism of Ca 3 CoRhO 6 has been investigated by magnetization studies. It is found that the solid solution, Ca 3-x Sr x CoRhO 6 , exists at least until about x = 1.0 without any change in the crystal structure. Apart from insensitivity of the spin-chain feature to volume expansion, the characteristic features of geometrical frustration interestingly appear at the same temperatures for all compositions, in sharp contrast to the response to Y substitution for Ca (reported previously). Interestingly, the huge frequency dependence of ac susceptibility known for the parent compound persists for all compositions. We do not find a change in the properties under external pressure. The stability of the magnetic anomalies of this compound to volume change (about 4%) is puzzling

  8. Robust high pressure stability and negative thermal expansion in sodium-rich antiperovskites Na{sub 3}OBr and Na{sub 4}OI{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yonggang, E-mail: yyggwang@gmail.com, E-mail: yangwg@hpstar.ac.cn, E-mail: yusheng.zhao@unlv.edu [High Pressure Science and Engineering Center, University of Nevada, Las Vegas, Nevada 89154 (United States); Institute of Nanostructured Functional Materials, Huanghe Science and Technology College, Zhengzhou, Henan 450006 (China); High Pressure Synergetic Consortium (HPSynC), Geophysical Laboratory, Carnegie Institution of Washington, Argonne, Illinois 60439 (United States); Wen, Ting [Institute of Nanostructured Functional Materials, Huanghe Science and Technology College, Zhengzhou, Henan 450006 (China); Park, Changyong; Kenney-Benson, Curtis [High Pressure Collaborative Access Team (HPCAT), Geophysical Laboratory, Carnegie Institution of Washington, Argonne, Illinois 60439 (United States); Pravica, Michael; Zhao, Yusheng, E-mail: yyggwang@gmail.com, E-mail: yangwg@hpstar.ac.cn, E-mail: yusheng.zhao@unlv.edu [High Pressure Science and Engineering Center, University of Nevada, Las Vegas, Nevada 89154 (United States); Yang, Wenge, E-mail: yyggwang@gmail.com, E-mail: yangwg@hpstar.ac.cn, E-mail: yusheng.zhao@unlv.edu [High Pressure Synergetic Consortium (HPSynC), Geophysical Laboratory, Carnegie Institution of Washington, Argonne, Illinois 60439 (United States); Center for High Pressure Science and Technology Advanced Research (HPSTAR), Shanghai 201203 (China)

    2016-01-14

    The structure stability under high pressure and thermal expansion behavior of Na{sub 3}OBr and Na{sub 4}OI{sub 2}, two prototypes of alkali-metal-rich antiperovskites, were investigated by in situ synchrotron X-ray diffraction techniques under high pressure and low temperature. Both are soft materials with bulk modulus of 58.6 GPa and 52.0 GPa for Na{sub 3}OBr and Na{sub 4}OI{sub 2}, respectively. The cubic Na{sub 3}OBr structure and tetragonal Na{sub 4}OI{sub 2} with intergrowth K{sub 2}NiF{sub 4} structure are stable under high pressure up to 23 GPa. Although being a characteristic layered structure, Na{sub 4}OI{sub 2} exhibits nearly isotropic compressibility. Negative thermal expansion was observed at low temperature range (20–80 K) in both transition-metal-free antiperovskites for the first time. The robust high pressure structure stability was examined and confirmed by first-principles calculations among various possible polymorphisms qualitatively. The results provide in-depth understanding of the negative thermal expansion and robust crystal structure stability of these antiperovskite systems and their potential applications.

  9. Robust high pressure stability and negative thermal expansion in sodium-rich antiperovskites Na3OBr and Na4OI2

    International Nuclear Information System (INIS)

    Wang, Yonggang; Wen, Ting; Park, Changyong; Kenney-Benson, Curtis; Pravica, Michael; Zhao, Yusheng; Yang, Wenge

    2016-01-01

    The structure stability under high pressure and thermal expansion behavior of Na 3 OBr and Na 4 OI 2 , two prototypes of alkali-metal-rich antiperovskites, were investigated by in situ synchrotron X-ray diffraction techniques under high pressure and low temperature. Both are soft materials with bulk modulus of 58.6 GPa and 52.0 GPa for Na 3 OBr and Na 4 OI 2 , respectively. The cubic Na 3 OBr structure and tetragonal Na 4 OI 2 with intergrowth K 2 NiF 4 structure are stable under high pressure up to 23 GPa. Although being a characteristic layered structure, Na 4 OI 2 exhibits nearly isotropic compressibility. Negative thermal expansion was observed at low temperature range (20–80 K) in both transition-metal-free antiperovskites for the first time. The robust high pressure structure stability was examined and confirmed by first-principles calculations among various possible polymorphisms qualitatively. The results provide in-depth understanding of the negative thermal expansion and robust crystal structure stability of these antiperovskite systems and their potential applications

  10. A Risk Analysis Methodology to Address Human and Organizational Factors in Offshore Drilling Safety: With an Emphasis on Negative Pressure Test

    Science.gov (United States)

    Tabibzadeh, Maryam

    According to the final Presidential National Commission report on the BP Deepwater Horizon (DWH) blowout, there is need to "integrate more sophisticated risk assessment and risk management practices" in the oil industry. Reviewing the literature of the offshore drilling industry indicates that most of the developed risk analysis methodologies do not fully and more importantly, systematically address the contribution of Human and Organizational Factors (HOFs) in accident causation. This is while results of a comprehensive study, from 1988 to 2005, of more than 600 well-documented major failures in offshore structures show that approximately 80% of those failures were due to HOFs. In addition, lack of safety culture, as an issue related to HOFs, have been identified as a common contributing cause of many accidents in this industry. This dissertation introduces an integrated risk analysis methodology to systematically assess the critical role of human and organizational factors in offshore drilling safety. The proposed methodology in this research focuses on a specific procedure called Negative Pressure Test (NPT), as the primary method to ascertain well integrity during offshore drilling, and analyzes the contributing causes of misinterpreting such a critical test. In addition, the case study of the BP Deepwater Horizon accident and their conducted NPT is discussed. The risk analysis methodology in this dissertation consists of three different approaches and their integration constitutes the big picture of my whole methodology. The first approach is the comparative analysis of a "standard" NPT, which is proposed by the author, with the test conducted by the DWH crew. This analysis contributes to identifying the involved discrepancies between the two test procedures. The second approach is a conceptual risk assessment framework to analyze the causal factors of the identified mismatches in the previous step, as the main contributors of negative pressure test

  11. Hemodynamic Changes After Static and Dynamic Exercises and Treadmill Stress Test; Different Patterns in Patients with Primary Benign Exertional Headache?

    Directory of Open Access Journals (Sweden)

    Mohsen Rostami

    2012-06-01

    Full Text Available The pathophysiology of primary benign exertional headache (EH is not still clearly defined. Some researchers have suggested an impaired vascular response as the etiology of this disorder. In this study we investigated whether there are any differences in blood pressure (BP and heart rate (HR of the subjects in course of the static and dynamic exercises and the treadmill stress test between those with and without EH. From university students, 22 patients with EH (mean age: 19.8 ± 2.10, Female to Male: 7:15 and 20 normal subjects (mean age: 19.3 ± 1.97, Female: Male: 8:12 were recruited. All the subjects performed the static and dynamic exercises at 30 and 20 percent of the maximal voluntary contraction (MVC and Bruce treadmill stress test according to the standard protocols. HR and BP of all the cases at the baseline and during and immediately after each test were measured. No significant difference was found between the mean rise of HR, systolic and diastolic BP of the subjects with and without EH in static and dynamic exercises and also treadmill stress test. It seems that between those with and without EH, there is no significant difference in rise of HR and BP response to static and dynamic exercises and treadmill stress test. Further studies are required to find the pathophysiology and risk factors of EH.

  12. Hemodynamic changes after static and dynamic exercises and treadmill stress test; different patterns in patients with primary benign exertional headache?

    Science.gov (United States)

    Kordi, Ramin; Mazaheri, Reza; Rostami, Mohsen; Mansournia, Mohammad Ali

    2012-01-01

    The pathophysiology of primary benign exertional headache (EH) is not still clearly defined. Some researchers have suggested an impaired vascular response as the etiology of this disorder. In this study we investigated whether there are any differences in blood pressure (BP) and heart rate (HR) of the subjects in course of the static and dynamic exercises and the treadmill stress test between those with and without EH. From university students, 22 patients with EH (mean age: 19.8 ± 2.10, Female to Male: 7:15) and 20 normal subjects (mean age: 19.3 ± 1.97, Female: Male: 8:12) were recruited. All the subjects performed the static and dynamic exercises at 30 and 20 percent of the maximal voluntary contraction (MVC) and Bruce treadmill stress test according to the standard protocols. HR and BP of all the cases at the baseline and during and immediately after each test were measured. No significant difference was found between the mean rise of HR, systolic and diastolic BP of the subjects with and without EH in static and dynamic exercises and also treadmill stress test. It seems that between those with and without EH, there is no significant difference in rise of HR and BP response to static and dynamic exercises and treadmill stress test. Further studies are required to find the pathophysiology and risk factors of EH.

  13. Cardiovascular responses to treadmill exercise in Nigerian ...

    African Journals Online (AJOL)

    The systolic blood pressure (SBP) and pressure rate product (PRP) during maximal exercise were also increased in hypertensives with LVH and hypertensive without LVH when compared to normotensive controls. The hypertensives with LVH and hypertensives without LVH also showed significant limitation to heart rate ...

  14. Cardiovascular responses to treadmill exercise in Nigerian ...

    African Journals Online (AJOL)

    2011-07-25

    Jul 25, 2011 ... The systolic blood pressure (SBP) and pressure rate product (PRP) ... Left ventricular hypertrophy (LVH) has been shown to be ... and functional evaluation of patients with cardiovascular ... excursion of the mitral valve leaflets. ..... blood flow reflecting diastolic behavior of the left ventricle in health and.

  15. Peripheral Microvascular Responses to Whole-Body Tilting, G(z) Centrifugation, and Lower Body Negative Pressure Stresses in Humans

    Science.gov (United States)

    Breit, G. A.; Watenpaugh, D. E.; Buckley, T. M.; Ballard, R. E.; Murthy, G.; Hargens, A. R.

    1994-01-01

    The response of the cutaneous microcirculation to orthostatic stress varies along the length of the body due to the interaction of central controls with regional responses to local blood pressure. We hypothesize that artificial orthostatic stresses such as Gz centrifugation and LBNP differ from whole-body tilting in terms of the distribution of microvascular blood flow. Cutaneous microvascular flows were measured by laser Doppler flowmetry at the neck, thigh, and leg of 15 normal subjects. Volunteers underwent stepwise head-up tilt (HUT) and short- and long-arm centrifugation protocols from supine control (0 Gz) to 0.2, 0.4, 0.6, 0.8, 1.0, 0.8, 0.6, 0.4, 0.2, and 0 Gz at the feet, for 30-s periods with 10-s transitions between levels. The same subjects underwent a corresponding supine LBNP protocol, up to 100 mmHg (in 20 mmHg increments) and back to zero pressure, which produced transmural pressure across blood vessels in the foot approximately equal to the HUT protocol. In general, application of all orthostatic stresses produced significant flow reductions in the lower body (p less than 0.05) and inconsistent changes in the neck. At low levels of each stress (0.4 Gz, 40 mmHg), LBNP generated the greatest relative reduction in flow in the lower body (-66.9+/-5.7%, thigh; -60.6 +/-5.7%, leg, mean +/- SE). HUT caused a less severe flow reduction than LBNP at the thigh and leg (-39.9 +/- 8.1% and -55.9+/-4.8%), while the effects induced by both forms of centrifugation were the least profound. Higher levels of each stress generally resulted in similar responses. These responses exhibit a consistent relationship to hypothesized changes in local microvascular transmural pressure, suggesting that myogenic and veno-arteriolar reflexes play a significant role in determining microvascular perfusion during orthostatic stress.

  16. Combined non-adaptive light and smell stimuli lowered blood pressure, reduced heart rate and reduced negative affect.

    Science.gov (United States)

    Dong, Shan; Jacob, Tim J C

    2016-03-15

    Bright light therapy has been shown to have a positive impact on seasonal affective disorder (SAD), depression and anxiety. Smell has also has been shown to have effects on mood, stress, anxiety and depression. The objective of this study was to investigate the effect of the combination of light and smell in a non-adaptive cycle. Human subjects were given smell (lemon, lavender or peppermint) and light stimuli in a triangular wave (60scycle) for 15min. Blood pressure and heart rate were monitored before and after each session for 5 consecutive days and a Profile of Mood States (POMS) test was administered before and after the sensory stimulation on days 1, 3 and 5. The light-smell stimulus lowered blood pressure, both systolic and diastolic, and reduced heart rate for all odours compared to control. Of the two sensory stimuli, the odour stimulus contributed most to this effect. The different aromas in the light-smell combinations could be distinguished by their different effects on the mood factors with lemon inducing the greatest mood changes in Dejection-Depression, Anger-Hostility, Tension-Anxiety. In conclusion, combined light and smell stimulation was effective in lowering blood pressure, reducing heart rate and improving mood. The combination was more effective than either smell or light stimuli alone, suggesting that a light-smell combination would be a more robust and efficacious alternative treatment for depression, anxiety and stress. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  17. Comparing handrim biomechanics for treadmill and overground wheelchair propulsion

    Science.gov (United States)

    Kwarciak, Andrew M.; Turner, Jeffrey T.; Guo, Liyun; Richter, W. Mark

    2010-01-01

    Study design Cross-sectional study. Objectives To compare handrim biomechanics recorded during overground propulsion to those recorded during propulsion on a motor-driven treadmill. Setting Biomechanics laboratory. Methods Twenty-eight manual wheelchair users propelled their own wheelchairs, at a self-selected speed, on a low-pile carpet and on a wheelchair accessible treadmill. Handrim biomechanics were recorded with an OptiPush instrumented wheelchair wheel. Results Across the two conditions, all handrim biomechanics were found to be similar and highly correlated (r > 0.85). Contact angle, peak force, average force, and peak axle moment differed by 1.6% or less across the two conditions. While not significant, power output and cadence tended to be slightly higher for the treadmill condition (3.5% and 3.6%, respectively), due to limitations in adjusting the treadmill grade. Conclusion Based on the results of this study, a motor-driven treadmill can serve as a valid surrogate for overground studies of wheelchair propulsion. PMID:21042332

  18. Intensive treadmill training in the acute phase after ischemic stroke

    DEFF Research Database (Denmark)

    Strømmen, Anna Maria; Christensen, Thomas; Jensen, Kai

    2016-01-01

    The aim of the study was to (a) assess the feasibility of intensive treadmill training in patients with acute ischemic stroke, (b) test whether physical activity of the legs during training increases with time, and (c) evaluate to what extent training sessions contribute toward the overall physical...... activity of these patients. Twenty hospitalized patients with acute ischemic stroke trained on a treadmill twice daily for 30 min for 5 days and on day 30. Physical activity was measured as activity counts (AC) from accelerometers. A total of 196 of 224 initiated training sessions were completed. Training...... with increasing number of days, with the median AC being 133% higher on day 5 than on day 1. AC in the paretic leg during 60 min of training constituted median 53% of the daytime AC. Early intensive treadmill training in acute ischemic stroke patients is thus feasible and contributes considerably toward...

  19. Implementation and adherence issues in a workplace treadmill desk intervention.

    Science.gov (United States)

    Tudor-Locke, Catrine; Hendrick, Chelsea A; Duet, Megan T; Swift, Damon L; Schuna, John M; Martin, Corby K; Johnson, William D; Church, Timothy S

    2014-10-01

    We report experiences, observations, and general lessons learned, specifically with regards to participant recruitment and adherence, while implementing a 6-month randomized controlled treadmill desk intervention (the WorkStation Pilot Study) in a real-world office-based health insurance workplace. Despite support from the company's upper administration, relatively few employees responded to the company-generated e-mail to participate in the study. Ultimately only 41 overweight/obese participants were deemed eligible and enrolled from a recruitment pool of 728 workers. Participants allocated to the Treadmill Desk Group found the treadmill desk difficult to use for 45 min twice a day as scheduled. Overall attendance averaged 45%-50% of all possible scheduled sessions. The most frequently reported reasons for missing sessions included work conflict (35%), out of office (30%), and illness/injury/drop-out (20%). Although focus groups indicated consistently positive comments about treadmill desks, an apparent challenge was fitting a rigid schedule of shared use to an equally rigid and demanding work schedule punctuated with numerous tasks and obligations that could not easily be interrupted. Regardless, we documented that sedentary office workers average ∼43 min of light-intensity (∼2 METs) treadmill walking daily in response to a scheduled, facilitated, and shared access workplace intervention. Workstation alternatives that combine computer-based work with light-intensity physical activity are a potential solution to health problems associated with excessive sedentary behavior; however, there are numerous administrative, capital, and human resource challenges confronting employers considering providing treadmill desks to workers in a cost-effective and equitable manner.

  20. Fundamentals of negative refractive index optical trapping: forces and radiation pressures exerted by focused Gaussian beams using the generalized Lorenz-Mie theory.

    Science.gov (United States)

    Ambrosio, Leonardo A; Hernández-Figueroa, Hugo E

    2010-11-04

    Based on the generalized Lorenz-Mie theory (GLMT), this paper reveals, for the first time in the literature, the principal characteristics of the optical forces and radiation pressure cross-sections exerted on homogeneous, linear, isotropic and spherical hypothetical negative refractive index (NRI) particles under the influence of focused Gaussian beams in the Mie regime. Starting with ray optics considerations, the analysis is then extended through calculating the Mie coefficients and the beam-shape coefficients for incident focused Gaussian beams. Results reveal new and interesting trapping properties which are not observed for commonly positive refractive index particles and, in this way, new potential applications in biomedical optics can be devised.

  1. Effect of negative pressure therapy on repair of soft tissues of the lower extremities in patients with neuropathic and neuroischaemic forms of diabetic foot syndrome

    Directory of Open Access Journals (Sweden)

    Ekaterina Leonidovna Zaytseva

    2014-06-01

    Full Text Available AimTo evaluate the efficiency of topical negative pressure wound therapy (NPWT compared with standard therapy for the regeneration of the soft tissues of the lower extremities in patients with diabetic foot syndrome.Materials and MethodsThe effects of negative pressure therapy on the clinical (size, tissue oxygenation, histological (light microscopy and immunohistochemical (CD68, MMP-9, TIMP-1 aspects of repair of the soft tissue of the lower extremities in patients with diabetes mellitus were compared with those of standard treatment. Thirty-one patients with diabetic foot ulcers were included in the study from the moment of debridement until the plastic closure of the wound. During the perioperative period, 13 patients received NPWT (-90 to -120 mmHg and 18 patients received standard therapy.ResultsA reduction of the wound area (26.6%±17.2% and the depth of the defects (40.5%±25.6% were achieved with negative pressure therapy compared with baseline data. In the control group, the corresponding values were 25.3%±19.4% and 21.8%±21.6%, respectively. The results of transcutaneous oximetry showed a greater increase in the level of local hemodynamics in the study group (p <0.04. An important criterion for wound preparation for a plastic closure is filling it with granulation tissue by more than 75%. In the study group, 95% of patients had wounds filled with 89.9%±17% of abundant granulation tissue. The histological data of the study group show a significant reduction of oedema by 80% (p <0.05, improved extracellular matrix organization (p <0.05, 90% (p <0.05 dissolution of inflammatory infiltrate and the formation of healthy granulation tissue (p <0.05. Immunohistochemical analysis demonstrated a significant decrease in the number of macrophages in the dermis (CD68 expression (p <0.05. In both groups, the level of MMP-9 was decreased. However, the ratio of MMP-9:TIMP-1 was lower in the study group (p <0.05.ConclusionThe findings suggest that

  2. Effect of Leaf Water Potential on Internal Humidity and CO2 Dissolution: Reverse Transpiration and Improved Water Use Efficiency under Negative Pressure.

    Science.gov (United States)

    Vesala, Timo; Sevanto, Sanna; Grönholm, Tiia; Salmon, Yann; Nikinmaa, Eero; Hari, Pertti; Hölttä, Teemu

    2017-01-01

    The pull of water from the soil to the leaves causes water in the transpiration stream to be under negative pressure decreasing the water potential below zero. The osmotic concentration also contributes to the decrease in leaf water potential but with much lesser extent. Thus, the surface tension force is approximately balanced by a force induced by negative water potential resulting in concavely curved water-air interfaces in leaves. The lowered water potential causes a reduction in the equilibrium water vapor pressure in internal (sub-stomatal/intercellular) cavities in relation to that over water with the potential of zero, i.e., over the flat surface. The curved surface causes a reduction also in the equilibrium vapor pressure of dissolved CO 2 , thus enhancing its physical solubility to water. Although the water vapor reduction is acknowledged by plant physiologists its consequences for water vapor exchange at low water potential values have received very little attention. Consequences of the enhanced CO 2 solubility to a leaf water-carbon budget have not been considered at all before this study. We use theoretical calculations and modeling to show how the reduction in the vapor pressures affects transpiration and carbon assimilation rates. Our results indicate that the reduction in vapor pressures of water and CO 2 could enhance plant water use efficiency up to about 10% at a leaf water potential of -2 MPa, and much more when water potential decreases further. The low water potential allows for a direct stomatal water vapor uptake from the ambient air even at sub-100% relative humidity values. This alone could explain the observed rates of foliar water uptake by e.g., the coastal redwood in the fog belt region of coastal California provided the stomata are sufficiently open. The omission of the reduction in the water vapor pressure causes a bias in the estimates of the stomatal conductance and leaf internal CO 2 concentration based on leaf gas exchange

  3. Effectiveness of treadmill training on balance control in elderly people: a randomized controlled clinical trial.

    Science.gov (United States)

    Pirouzi, Soraya; Motealleh, Ali Reza; Fallahzadeh, Fatemeh; Fallahzadeh, Mohammad Amin

    2014-11-01

    Physical exercise would improve postural stability, which is an essential factor in preventing accidental fall among the elderly population. The aim of this study is to examine the effectiveness of treadmill walking on balance improvement among the elderly people. A total of 30 community dwelling older adults with a Berg Balance Scale score of 36-48 and the ability to walk without aid were considered and divided into control (n=15) and experimental (n=15) groups. Individuals in the experimental group participated in 30 minutes of forward and backward treadmill training based on three times a week interval for a period of four weeks. Individuals in the control group were instructed to continue with their daily routine activity. Before and after training, gait speed was measured by six-minute walk test and balance ability was evaluated by Fullerton Advanced Balance Scale (FABS) and Berg Balance Scale (BBS) tests. Postural sway items such as the Center of Pressure (COP), average displacement and velocity were evaluated by using a force platform system. Data were collected in quiet standing, tandem position and standing on foam pads before and after intervention. After intervention, balance variables in the experimental group indicated a significant improvement in quiet standing on firm and foam surfaces, but no considerable improvement was shown in tandem position. A between-group comparison showed a significant reduction in COP velocity in the sagittal plane (P=0.030) during quiet standing and in the frontal plane (P=0.001) during standing on foam, whereas no significant reduction in COP parameters during tandem position was found. It is recommended that twelve sessions of forward and backward treadmill walk are effective in balance improvement in elderly people. IRCT201209199440N2.

  4. Effectiveness of Treadmill Training on Balance Control in Elderly People: A Randomized Controlled Clinical Trial

    Directory of Open Access Journals (Sweden)

    Soraya Pirouzi

    2014-11-01

    Full Text Available Physical exercise would improve postural stability, which is an essential factor in preventing accidental fall among the elderly population. The aim of this study is to examine the effectiveness of treadmill walking on balance improvement among the elderly people. A total of 30 community dwelling older adults with a Berg Balance Scale score of 36-48 and the ability to walk without aid were considered and divided into control (n=15 and experimental (n=15 groups. Individuals in the experimental group participated in 30 minutes of forward and backward treadmill training based on three times a week interval for a period of four weeks. Individuals in the control group were instructed to continue with their daily routine activity. Before and after training, gait speed was measured by six-minute walk test and balance ability was evaluated by Fullerton Advanced Balance Scale (FABS and Berg Balance Scale (BBS tests. Postural sway items such as the Center of Pressure (COP, average displacement and velocity were evaluated by using a force platform system. Data were collected in quiet standing, tandem position and standing on foam pads before and after intervention. After intervention, balance variables in the experimental group indicated a significant improvement in quiet standing on firm and foam surfaces, but no considerable improvement was shown in tandem position. A between-group comparison showed a significant reduction in COP velocity in the sagittal plane (P=0.030 during quiet standing and in the frontal plane (P=0.001 during standing on foam, whereas no significant reduction in COP parameters during tandem position was found. It is recommended that twelve sessions of forward and backward treadmill walk are effective in balance improvement in elderly people. Trial Registration Number: IRCT201209199440N2

  5. Outcomes in Asymptomatic Severe Aortic Stenosis With Preserved Ejection Fraction Undergoing Rest and Treadmill Stress Echocardiography.

    Science.gov (United States)

    Huded, Chetan P; Masri, Ahmad; Kusunose, Kenya; Goodman, Andrew L; Grimm, Richard A; Gillinov, A Marc; Johnston, Douglas R; Rodriguez, L Leonardo; Popovic, Zoran B; Svensson, Lars G; Griffin, Brian P; Desai, Milind Y

    2018-04-12

    In asymptomatic patients with severe aortic stenosis and preserved left ventricular ejection fraction, we sought to assess the incremental prognostic value of resting valvuloarterial impedence (Zva) and left ventricular global longitudinal strain (LV-GLS) to treadmill stress echocardiography. We studied 504 such patients (66±12 years, 78% men, 32% with coronary artery disease who underwent treadmill stress echocardiography between 2001 and 2012. Clinical and exercise variables (% of age-sex predicted metabolic equivalents [%AGP-METs]) were recorded. Resting Zva ([systolic arterial pressure+mean aortic valve gradient]/[LV-stroke volume index]) and LV-GLS (measured offline using Velocity Vector Imaging, Siemens) were obtained from the baseline resting echocardiogram. Death was the primary outcome. There were no major adverse cardiac events during treadmill stress echocardiography. Indexed aortic valve area, Zva, and LV-GLS were 0.46±0.1 cm 2 /m 2 , 4.5±0.9 mm Hg/mL per m 2 and -16±4%, respectively; only 50% achieved >100% AGP-METs. Sixty-four percent underwent aortic valve replacement. Death occurred in 164 (33%) patients over 8.9±3.6 years (2 within 30 days of aortic valve replacement). On multivariable Cox survival analysis, higher Society of Thoracic Surgeons score (hazard ratio or HR 1.06), lower % AGP-METS (HR 1.16), higher Zva (HR 1.25) and lower LV-GLS (HR 1.12) were associated with higher longer-term mortality, while aortic valve replacement (HR 0.45) was associated with improved survival (all P statistic from 0.65 to 0.69 and 0.75, respectively, both P stress echocardiography, LV-GLS and ZVa offer incremental prognostic value. © 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

  6. Spectroscopic diagnosis of plasma in atmospheric pressure negative pulsed gas-liquid discharge with nozzle-cylinder electrode

    Science.gov (United States)

    Ming, SUN; Zhan, TAO; Zhipeng, ZHU; Dong, WANG; Wenjun, PAN

    2018-05-01

    The plasma characteristics of a gas-liquid phase discharge reactor were investigated by optical and electrical methods. The nozzle-cylinder electrode in the discharge reactor was supplied with a negative nanosecond pulsed generator. The optical emission spectrum diagnosis revealed that OH (A2∑+ → X2Π, 306–309 nm), N2 (C3Π→B3Πg, 337 nm), O (3p5p→3s5s0, 777.2 nm) and O (3p3p→3s3s0, 844.6 nm) were produced in the discharge plasma channels. The electron temperature (T e) was calculated from the emission relative intensity ratio between the atomic O 777.2 nm and 844.6 nm, and it increased with the applied voltage and the pulsed frequency and fell within the range of 0.5–0.8 eV. The gas temperature (T g) that was measured by Lifbase was in a range from 400 K to 600 K.

  7. Abdominal Cavity Eventration Treated by Means of the "Open Abdomen" Technique Using the Negative Pressure Therapy System--Case Report and Literature Review.

    Science.gov (United States)

    Trzeciak, Piotr W; Porzeżyńska, Joanna; Ptasińska, Karolina; Walczak, Dominik A

    2015-11-01

    Wound dehiscence is a surgical complication in which the wound ruptures along the surgical suture with abdominal cavity bowel displacement. It is observed in 0.2-6% of operated patients. The extensive wound is a gateway for infection. Moreover, increased secretion of serous fluid induces a hygienic problem and may lead to secondary skin infections or bedsores. The negative pressure wound therapy (NPWT) system is an innovative therapeutic method. It perfectly executes the TIME strategy, receiving more and more recognition. The study presented a case of a 62-year old male patient after several consecutive wound dehiscence episodes who was primarily treated for rectal cancer by means of low anterior resection of the rectum. Due to acute respiratory insufficiency after several operations, wound necrosis with dehiscence was observed. Considering the high risk of perioperative death we abandoned surgical treatment and introduced conservative management using negative pressure wound therapy until the patient's health improved. Literature regarding the above-mentioned issue was also reviewed.

  8. The SNaP™ Wound Care System: A Case Series Using a Novel Ultraportable Negative Pressure Wound Therapy Device for the Treatment of Diabetic Lower Extremity Wounds

    Science.gov (United States)

    Lerman, Bruce; Oldenbrook, Leslie; Ryu, Justin; Fong, Kenton D.; Schubart, Peter J.

    2010-01-01

    Although there is significant evidence supporting the use of negative pressure wound therapy (NPWT) for the treatment of lower extremity diabetic ulcers, currently available electrically powered NPWT systems are not ideally suited for treating smaller diabetic foot ulcers. The Smart Negative Pressure (SNaP™) Wound Care System is a novel, ultraportable device that delivers NPWT without the use of an electrically powered pump. It was specifically designed to meet the wound care needs of patients with diabetes. The SNaP System is compact, silent, mobile, easy-to-use, and available off-the-shelf. It is fully disposable and may offer other important benefits over electrically powered systems to both the clinician and patient. We review the evidence for use of NPWT for the treatment of diabetic wounds and discuss the potential benefits of this new NPWT technology for patients with diabetes. We also present a case series of four difficult lower extremity diabetic ulcers that were successfully treated with the SNaP System. This study suggests that the SNaP System may be a useful addition to the armamentarium of the diabetic wound care clinician. PMID:20663444

  9. Stagnations of increasing trends in negative pressure with repeated cavitation in water/metal Berthelot tubes as a result of mechanical sealing

    International Nuclear Information System (INIS)

    Hiro, Kazuki; Ohde, Yoshihito; Tanzawa, Yasutoshi

    2003-01-01

    To investigate effects of mechanical sealing on negative pressures in water/metal tube Berthelot systems, trends in negative pressure are observed through runs of temperature cycles below 90 deg. C in two systems made of metals having small amounts of gas inclusions. The first system is a pre-degassed all-stainless-steel tube/plug system. The steel is a special product for vacuum engineering. The second is the same tube sealed with plugs made of silver solidified one-dimensionally in a vacuum furnace. A new type of trend, stagnation for intermediate cycles is found in both systems so long as sealing distortion of each plug is small in amount. The stagnation period for the first system is longer than that for the second one. A metallurgical mechanism of a gas-being-replenished crevice model is proposed: distorted parts of metals undergo heat-treatment during runs of temperature cycles, and the heat-treatment enhances the rates of impurity gas transports to crevices on the metal surface where cavitation occurs, and the transport causes the stagnation for cycles during which the rates are still high

  10. Treadmilling of actin filaments via Brownian dynamics simulations

    DEFF Research Database (Denmark)

    Guo, Kunkun; Shillcock, Julian C.; Lipowsky, Reinhard

    2010-01-01

    . For concentrations close to the critical concentration CT = CT,cr, the filaments undergo treadmilling, i.e., they grow at the barbed and shrink at the pointed end, which leads to directed translational motion of the whole filament. The corresponding nonequilibrium states are characterized by several global fluxes...

  11. Ghost crabs on a treadmill: Oxygen Uptake and Haemocyanin ...

    African Journals Online (AJOL)

    Ghost crabs Ocypode ceratophthalmus were exercised on a specially constructed treadmill. At a running speed of 13,3 cm s-1, most crabs ran for 2 h before getting fatigued. At this speed the oxygen consumption rate (MO2) was measured in time intervals for a total of 52 min. For exercised crabs the MO2 values are about ...

  12. Integrated effect of treadmill training combined with dynamic ankle ...

    African Journals Online (AJOL)

    Abd El Aziz Ali Sherief

    2015-01-13

    Jan 13, 2015 ... of this study was to determine the combined effects of treadmill and dynamic ankle foot ... electrical stimulation, constrained induced therapy and ortho- ... restricted plantar flexion. .... older). (2) The child performs the item according to the criteria ... applied and intended to control position and motion of the.

  13. Gait Coordination After Stroke: Benefits of Acoustically Paced Treadmill Walking

    NARCIS (Netherlands)

    Roerdink, M.; Lamoth, C.J.C.; Kwakkel, G.; van Wieringen, P.C.W.; Beek, P.J.

    2007-01-01

    Background and Purpose: Gait coordination often is compromised after stroke. The purpose of this study was to evaluate the efficacy of acoustically paced treadmill walking as a method for improving gait coordination in people after stroke. Participants: Ten people after stroke volunteered for the

  14. Gait coordination after stroke: benefits of acoustically paced treadmill walking.

    NARCIS (Netherlands)

    Roerdink, M.; Lamoth, C.J.; Kwakkel, G.; Wieringen, P.C. van; Beek, P.J.

    2007-01-01

    BACKGROUND AND PURPOSE: Gait coordination often is compromised after stroke. The purpose of this study was to evaluate the efficacy of acoustically paced treadmill walking as a method for improving gait coordination in people after stroke. PARTICIPANTS: Ten people after stroke volunteered for the

  15. Peak Cardiorespiratory Responses of Patients with Subacute Stroke During Land and Aquatic Treadmill Exercise.

    Science.gov (United States)

    Lee, Yong Ki; Kim, Bo Ryun; Han, Eun Young

    2017-05-01

    The aim of this work was to investigate the cardiorespiratory responses of patients with subacute stroke to exercise stress tests with aquatic and land treadmills. Twenty-one consecutive patients who presented with first-ever subacute stroke in 2013-2015. All subjects underwent symptom-limited incremental exercise testing with aquatic and land treadmills. Land treadmill speed started at 1.5 km/h and increased 0.5 km/h every 1 to 2 minutes until maximal tolerable speed was achieved. Thereafter, the grade was elevated by 2% every 2 minutes. In the aquatic treadmill test, subjects were submerged to the xiphoid in 28°C water. Treadmill speed started at 1.5 km/h and was increased 0.5 km/h every 2 minutes thereafter. Cardiorespiratory responses were recorded with aquatic and land treadmills. Compared to land treadmill exercise, aquatic treadmill exercise achieved significantly better peak VO2 (22.0 vs 20.0; P = 0.02), peak metabolic equivalents (6.3 vs 5.8; P = 0.02), and peak rating of perceived exertion (17.6 vs 18.4, P = 0.01). Heart rate and VO2 correlated significantly during both tests (land treadmill: r = 0.96, P aquatic treadmill: r = 0.99, P Aquatic treadmill exercise elicited significantly better peak cardiorespiratory responses than land treadmill exercise and may be as effective for early intensive aerobic training in subacute stroke patients.

  16. Establishing a Practical Treadmill Sprint as an Alternative to the Wingate Anaerobic Test

    Science.gov (United States)

    McKie, Greg L.; Islam, Hashim; Townsend, Logan K.; Howe, Greg J.; Hazell, Tom J.

    2018-01-01

    This study examined the validity and reliability of a 30-second running sprint test using two non-motorized treadmills compared to the established Wingate Anaerobic Test. Twenty-four participants completed three sessions in a randomized order on a: (1) manual mode treadmill (Woodway); (2) specialized interval training treadmill (HiTrainer); and…

  17. Tissue Oxygenation and Negative-Pressure Wound Therapy When Applied to the Feet of Persons With Diabetes Mellitus: An Observational Study.

    Science.gov (United States)

    Lee, Ye-Na; Lee, Jong Seok; Han, Seung-Kyu; Jung, Hye-Kyung

    Our group has reported that negative-pressure wound therapy (NPWT) decreases tissue oxygenation by 84% in the foot of diabetic patients because the pad of the connecting drainage tube and foam sponge of the NPWT system compress the wound bed. The purpose of this study was to determine whether an NPWT modified dressing application reduces tissue oxygenation in the feet of persons with diabetes mellitus. A prospective, clinical, observational study. We enrolled 30 patients with diabetic mellitus; their mean age was 63.9 ± 11.2 years (mean ± standard deviation). All were cared for at the diabetic wound center at an academic tertiary medical center in South Korea between 2014 and January 2015. Transcutaneous partial oxygen pressures (TcpO2) were measured to determine tissue oxygenation levels beneath modified NPWT dressings. A TcpO2 sensor was fixed at the tarsometatarsal area of the contralateral unwounded foot. A negative pressure of -125 mm Hg was applied until TcpO2 reached a plateau state; values were measured before, during, and after the modified NPWT. The Wilcoxon' and Mann-Whitney U tests were used to compare differences between these measurements. TcpO2 levels decreased by 26% during the modified NPWT. Mean TcpO2 values before, during, and after turning off the therapy were 54.3 ± 15.3 mm Hg, 41.6 ± 16.3 mm Hg, and 53.3 ± 15.6 mm Hg (P drainage tube significantly reduces the amount of tissue oxygenation loss beneath foam dressings on the skin of the foot dorsum in diabetic patients.

  18. Biomechanical Analysis of Treadmill Locomotion on the International Space Station

    Science.gov (United States)

    De Witt, J. K.; Fincke, R. S.; Guilliams, M. E.; Ploutz-Snyder, L. L.

    2011-01-01

    Treadmill locomotion exercise is an important aspect of ISS exercise countermeasures. It is widely believed that an optimized treadmill exercise protocol could offer benefits to cardiovascular and bone health. If training heart rate is high enough, treadmill exercise is expected to lead to improvements in aerobic fitness. If impact or bone loading forces are high enough, treadmill exercise may be expected to contribute to improved bone outcomes. Ground-based research suggests that joint loads increase with increased running speed. However, it is unknown if increases in locomotion speed results in similar increases in joint loads in microgravity. Although data exist regarding the biomechanics of running and walking in microgravity, a majority were collected during parabolic flight or during investigations utilizing a microgravity analog. The Second Generation Treadmill (T2) has been in use on the International Space Station (ISS) and records the ground reaction forces (GRF) produced by crewmembers during exercise. Biomechanical analyses will aid in understanding potential differences in typical gait motion and allow for modeling of the human body to determine joint and muscle forces during exercise. By understanding these mechanisms, more appropriate exercise prescriptions can be developed that address deficiencies. The objective of this evaluation is to collect biomechanical data from crewmembers during treadmill exercise prior to and during flight. The goal is to determine if locomotive biomechanics differ between normal and microgravity environments and to determine how combinations of subject load and speed influence joint loading during in-flight treadmill exercise. Further, the data will be used to characterize any differences in specific bone and muscle loading during locomotion in these two gravitational conditions. This project maps to the HRP Integrated Research Plan risks including Risk of Bone Fracture (Gap B15), Risk of Early Onset Osteoporosis Due to

  19. The effect of positive and negative message framing on short term continuous positive airway pressure compliance in patients with obstructive sleep apnea.

    Science.gov (United States)

    Pengo, Martino F; Czaban, Marcin; Berry, Marc P; Nirmalan, Prajeshan; Brown, Richard; Birdseye, Adam; Woroszyl, Asia; Chapman, Julia; Kent, Brian D; Hart, Nicholas; Rossi, Gian Paolo; Steier, Joerg

    2018-01-01

    Continuous positive airway pressure (CPAP), the best available treatment for obstructive sleep apnea (OSA), requires long-term compliance to be effective. Behavioral interventions may be used to improve adherence to CPAP. We aimed to investigate whether positive or negative message framing impacts on CPAP compliance in patients with OSA, when compared to standard care. Consenting patients with confirmed OSA were randomly allocated to receive along with their CPAP either positively or negatively framed messages (Pos; Neg), or standard care (Con). Standardized motivational messages were read out to patients during an initial teaching session and through weekly telephone calls. Patients' compliance data were reviewed 2 and 6 weeks following CPAP initiation. We randomized 112 patients to groups that were matched for age, BMI, and OSA severity. The positively framed group (Pos) showed greater CPAP usage after 2 weeks (total use 53.7±31.4 hours) as compared to the negatively framed and the control group (35.6±27.4 and 40.8±33.5 hours, Pframed groups (Pos n=5; Neg n=8; Con n=11; Pframed messages can improve CPAP adherence in patients with OSA in the short-term; however, strategies for implementing its long-term use need to be developed.

  20. Cerebral Blood Flow Responses to Aquatic Treadmill Exercise.

    Science.gov (United States)

    Parfitt, Rhodri; Hensman, Marianne Y; Lucas, Samuel J E

    2017-07-01

    Aquatic treadmills are used as a rehabilitation method for conditions such as spinal cord injury, osteoarthritis, and stroke, and can facilitate an earlier return to exercise training for athletes. However, their effect on cerebral blood flow (CBF) responses has not been examined. We tested the hypothesis that aquatic treadmill exercise would augment CBF and lower HR compared with land-based treadmill exercise. Eleven participants completed incremental exercise (crossover design) starting from walking pace (4 km·h, immersed to iliac crest [aquatic], 6 km·h [land]) and increasing 1 km·h every 2 min up to 10 km·h for aquatic (maximum belt speed) or 12 km·h for land. After this, participants completed two 2-min bouts of exercise immersed to midthigh and midchest at constant submaximal speed (aquatic), or were ramped to exhaustion (land; increased gradient 2° every min). Middle cerebral artery blood flow velocity (MCAv) and HR were measured throughout, and the initial 10 min of each protocol and responses at each immersion level were compared. Compared with land-based treadmill, MCAvmean increased more from baseline for aquatic exercise (21% vs 12%, P aquatic walking compared with land-based moderate intensity running (~10 cm·s, P = 0.56). Greater water immersion lowered HR (139 vs 178 bpm for midchest vs midthigh), whereas MCAvmean remained constant (P = 0.37). Findings illustrate the potential for aquatic treadmill exercise to enhance exercise-induced elevations in CBF and thus optimize shear stress-mediated adaptation of the cerebrovasculature.

  1. Step-to-step variability in treadmill walking: influence of rhythmic auditory cueing.

    Directory of Open Access Journals (Sweden)

    Philippe Terrier

    Full Text Available While walking, human beings continuously adjust step length (SpL, step time (SpT, step speed (SpS = SpL/SpT and step width (SpW by integrating both feedforward and feedback mechanisms. These motor control processes result in correlations of gait parameters between consecutive strides (statistical persistence. Constraining gait with a speed cue (treadmill and/or a rhythmic auditory cue (metronome, modifies the statistical persistence to anti-persistence. The objective was to analyze whether the combined effect of treadmill and rhythmic auditory cueing (RAC modified not only statistical persistence, but also fluctuation magnitude (standard deviation, SD, and stationarity of SpL, SpT, SpS and SpW. Twenty healthy subjects performed 6 × 5 min. walking tests at various imposed speeds on a treadmill instrumented with foot-pressure sensors. Freely-chosen walking cadences were assessed during the first three trials, and then imposed accordingly in the last trials with a metronome. Fluctuation magnitude (SD of SpT, SpL, SpS and SpW was assessed, as well as NonStationarity Index (NSI, which estimates the dispersion of local means in the times series (SD of 20 local means over 10 steps. No effect of RAC on fluctuation magnitude (SD was observed. SpW was not modified by RAC, what is likely the evidence that lateral foot placement is separately regulated. Stationarity (NSI was modified by RAC in the same manner as persistent pattern: Treadmill induced low NSI in the time series of SpS, and high NSI in SpT and SpL. On the contrary, SpT, SpL and SpS exhibited low NSI under RAC condition. We used relatively short sample of consecutive strides (100 as compared to the usual number of strides required to analyze fluctuation dynamics (200 to 1000 strides. Therefore, the responsiveness of stationarity measure (NSI to cued walking opens the perspective to perform short walking tests that would be adapted to patients with a reduced gait perimeter.

  2. High negative pressure subcutaneous suction drain for managing debilitating subcutaneous emphysema secondary to tube thoracostomy for an iatrogenic post computed tomography guided transthoracic needle biopsy pneumothorax: Case report and review of literature

    Directory of Open Access Journals (Sweden)

    Zeeshan Ahmed

    2016-01-01

    Conclusion: Debilitating subcutaneous emphysema which causes distress, anxiety, palpebral closure, dyspnoea or dysphagia requires intervention. High negative pressure subcutaneous suction drain provides immediate and sustained relief in extensive and debilitating SE.

  3. The use of isoprene as a novel dopant in negative ion atmospheric pressure photoionization mass spectrometry coupled to high-performance liquid chromatography.

    Science.gov (United States)

    Dousty, Faezeh; O'Brien, Rob

    2015-06-15

    As in the case with positive ion atmospheric pressure photoionization (PI-APPI), the addition of dopants significantly improves the sensitivity of negative ion APPI (NI-APPI). However, the research on dopant-assisted-NI-APPI has been quite limited compared to the studies on dopant-assisted PI-APPI. This work presents the potential of isoprene as a novel dopant for NI-APPI. Thirteen compounds, possessing suitable gas-phase ion energetic properties in order to make stable negative ions, were selected. Dopants were continuously introduced into a tee junction prior to the ion source through a fused-silica capillary, while analytes were directly injected into the same tee. Then both were mixed with the continuous solvent from high-performance liquid chromatography (HPLC), nebulized, and entered the source. The nebulized stream was analyzed by APPI tandem quadrupole mass spectrometry in the negative ion mode. The results obtained using isoprene were compared with those obtained by using toluene as a dopant and dopant-free NI-APPI. Isoprene enhanced the ionization intensities of the studied compounds, which were found to be comparable and, in some cases, more effective than toluene. The mechanisms leading to the observed set of negative analyte ions were also discussed. Because in NI-APPI, thermal electrons, which are produced during the photoionization of a dopant, are considered the main reagent ions, both isoprene and toluene promoted the ionization of analytes through the same mechanisms, as expected. Isoprene was shown to perform well as a novel dopant for NI-APPI. Isoprene has a high photoabsorption cross section in the VUV region; therefore, its photoionization leads to a highly effective production of thermal electrons, which further promotes the ionization of analytes. In addition, isoprene is environmentally benign and less toxic compared to currently used dopants. Copyright © 2015 John Wiley & Sons, Ltd.

  4. Management of the open abdomen using negative pressure wound therapy with instillation in severe abdominal sepsis: A review of 48 cases in Hospital Mexico, Costa Rica.

    Science.gov (United States)

    Sibaja, Pablo; Sanchez, Alfredo; Villegas, Guillermo; Apestegui, Alvaro; Mora, Esteban

    2017-01-01

    Despite the numerous advances in recent years, severe abdominal sepsis (with associated organ failure associated with infection) remains a serious, life-threatening condition with a high mortality rate. OA is a viable alternative to the previously used scheduled repeat laparotomy or continuous peritoneal lavage. The use of Negative Pressure Wound Therapy (NPWT) has been described as a successful method of management of the open abdomen. Adding instillation of saline solution to NPWT in a programmed and controlled manner, could offer the clinician an additional tool for the management of complex septic abdomen. To explore if the concept of active two-way therapy (Negative pressure wound therapy with instillation or NPWT-I) yields superior control of underlying, life-threatening abdominal infections and its effects on survival and morbidity in patients with severe abdominal sepsis when management with an open abdomen is required. A retrospective review of 48 patients with severe abdominal sepsis, who were managed with and open abdomen and NPWT-I was performed. NPWT-I was initiated utilizing the same parameters on all patients, this consisted of cycles of instillation of saline solution, which was removed through negative pressure after a short dwell period. We observed the effects on primary fascia closure rate, mortality, hospital and SICU length of stay and associated complications. Our patient group consisted of 20 (42%) males and 28 (58%) females. Average age was 48 years. Mortality in these patients was attributed to pulmonary embolism (n=1), acute renal failure (n=2) and cardiopulmonary arrest (n=1). Average total hospital stay was 24days, and stay in the SICU (n=26) averaged 7.5days. No acute complications related to the NPWT-I. All patients presenting with abdominal compartment syndrome resolved after initiation of the NPWT-I. A total of 46 patients (96%) patients achieved fascia closure after NPWT-I therapy after an average of 6days. Four patients (8%) died

  5. Aerial medical evacuation of health workers with suspected Ebola virus disease in Guinea Conakry-interest of a negative pressure isolation pod-a case series.

    Science.gov (United States)

    Dindart, Jean-Michel; Peyrouset, Olivier; Palich, Romain; Bing, Abdoul; Kojan, Richard; Barbe, Solenne; Harouna, Souley; Blackwell, Nikki

    2017-03-11

    We report 4 cases of Health Workers (HW) suspected of having contracted Ebola Virus Disease (EVD), transported from the Alliance for International Medical Action (ALIMA) Ebola Treatment Centre (ETC) in N'Zerekore, Guinea to the Treatment Centre for Carers run by the medical corps of the French army in Conakry, the capital of Guinea, which was established on 17 January 2015 and closed on 7 July 2015. In total more than 500 HWs have died from EVD since the epidemic began. This mortality has had significant effects on the ability of local services to respond appropriately to the disaster. The HWs were transported by air in the "Human Stretcher Transit Isolator-Total Containment (Oxford) Limited" (HSTI-TCOL) negative pressure isolation pod. Medical evacuation of patients with suspected, potentially fatal, infectious diseases is feasible with the use of a light isolator for patients without critical dysfunctions.

  6. Foliar δ13C Showed No Altitudinal Trend in an Arid Region and Atmospheric Pressure Exerted a Negative Effect on Plant δ13C

    Directory of Open Access Journals (Sweden)

    Zixun Chen

    2017-07-01

    Full Text Available Previous studies have suggested foliar δ13C generally increases with altitude. However, some observations reported no changes or even decreased trends in foliar δ13C. We noted that all the studies in which δ13C increased with elevation were conducted in the human regions, whereas those investigations in which δ13C did not vary or decreased were conducted in areas with water stress. Thus, we proposed that the pattern of increasing δ13C with elevation is not a general one, and that δ13C may remain unchanged or decrease in plants grown in arid environments. To test the hypothesis, we sampled plants along altitude gradients on the shady and sunny slopes of Mount Tianshan characterized by arid and semiarid climates. The measurements of foliar δ13C showed no altitudinal trends for the plants grown on either of the slopes. Therefore, this study supported our hypothesis. In addition, the present study addressed the effect of atmospheric pressure on plant δ13C by accounting for the effects of temperature and precipitation on δ13C. This study found that the residual foliar δ13C increased with increasing altitude, suggesting that atmospheric pressure played a negative role in foliar δ13C.

  7. Walking on an Oscillating Treadmill: Two Paths to Functional Adaptation

    Science.gov (United States)

    Brady, Rachel A.; Peters, Brian T.; Bloomberg, Jacob J.

    2010-01-01

    We mounted a treadmill on top of a six degree-of-freedom motion base platform to investigate and characterize locomotor responses produced by healthy adults when introduced to a novel walking condition. Subjects were classified into two groups according to how their stride times were affected by the perturbation. Our data suggest that a person's choice of adaptation strategy is influenced by the relationship between his unique, natural stride frequency and the external frequency imposed by the motion base. Our data suggest that a person's stride time response while walking on a laterally oscillating treadmill is influenced by the relationship between his unique, natural stride frequency and the imposed external frequency of the motion base. This relationship may be useful for checking the efficacy of gait training and rehabilitation programs. Preselecting and manipulating a person's EST could be one way to draw him out of his preferred "entrainment well" during therapy or training.

  8. Burning more than calories: treadmill friction injuries in children.

    LENUS (Irish Health Repository)

    Davidson, C C

    2012-02-01

    Treadmill injuries in young children are a serious but little documented problem. Friction burns occur when the hands come into contact with the moving belt resulting in deep burns that often require hospital admission and surgery. The aim of this study was to assess the nature and prevalence of injuries sustained and to highlight treadmill friction burns as a public health issue previously undocumented in Ireland. A retrospective chart review from January 2006 until March 2008 was performed and functional outcome was assessed by the modified Michigan Hand Outcomes Questionnaire. Eight girls and four boys from one year and seven months to seven years and five months were treated. Eight children required admission to hospital and to date three have required surgery for their injuries. This is a new and increasing problem in Ireland which must be highlighted.

  9. How many electrocardiographic leads are required for exercise treadmill tests

    International Nuclear Information System (INIS)

    Miller, T.D.; Desser, K.B.; Lawson, M.

    1987-01-01

    Forty-four consecutive patients who had perfusion defects on thallium-201 scanning and positive exercise treadmill tests were prospectively studied. Thirty-eight (86%) subjects had diagnostic ST segment changes in lead V5, 37 (84%) in lead V4, and 44 (100%) in either lead V4, V5 or both. Thirty patients had ST segment changes in the inferior leads, 20 in lead aVR, and only four in lead I and/or aVL. All of these latter subjects had diagnostic ST segments in lead V4 and/or V5. It is concluded that: combined electrocardiographic leads V4 and V5 detect the vast majority of ischemic changes during exercise treadmill testing, regardless of the site of perfusion defects detected by thallium-201 scanning; and monitoring the inferior and lateral leads rarely provides more diagnostic information

  10. Incisional Negative Pressure Wound Therapy

    DEFF Research Database (Denmark)

    Hyldig, Nana; Birke-Sorensen, Hanne; Kruse, Marie

    and meta-analysis of randomized controlled trials of NPWT compared to standard postoperative dressings on closed incisions. Results: Ten studies met the inclusion criteria, reporting on 1344 incisions (1121 patients). NPWT was associated with a significant reduction of wound infection (46%), and seroma...... formation (52%) compared to standard care. The reduction in wound dehiscence was not statistically significant. The numbers needed to treat were 3 (seroma), 17 (dehiscence), and 25 (infection). Methodical heterogeneity across studies led to downgrading quality of evidence to moderate for infection...

  11. Negligible motion artifacts in scalp electroencephalography (EEG during treadmill walking

    Directory of Open Access Journals (Sweden)

    Kevin eNathan

    2016-01-01

    Full Text Available Recent Mobile Brain/Body Imaging (MoBI techniques based on active electrode scalp electroencephalogram (EEG allow the acquisition and real-time analysis of brain dynamics during active unrestrained motor behavior involving whole body movements such as treadmill walking, over-ground walking and other locomotive and non-locomotive tasks. Unfortunately, MoBI protocols are prone to physiological and non-physiological artifacts, including motion artifacts that may contaminate the EEG recordings. A few attempts have been made to quantify these artifacts during locomotion tasks but with inconclusive results due in part to methodological pitfalls. In this paper, we investigate the potential contributions of motion artifacts in scalp EEG during treadmill walking at three different speeds (1.5, 3.0, and 4.5 km/h using a wireless 64 channel active EEG system and a wireless inertial sensor attached to the subject’s head. The experimental setup was designed according to good measurement practices using state-of-the-art commercially-available instruments, and the measurements were analyzed using Fourier analysis and wavelet coherence approaches. Contrary to prior claims, the subjects’ motion did not significantly affect their EEG during treadmill walking although precaution should be taken when gait speeds approach 4.5 km/h. Overall, these findings suggest how MoBI methods may be safely deployed in neural, cognitive, and rehabilitation engineering applications.

  12. Phototherapy during treadmill training improves quadriceps performance in postmenopausal women.

    Science.gov (United States)

    Paolillo, F R; Corazza, A V; Paolillo, A R; Borghi-Silva, A; Arena, R; Kurachi, C; Bagnato, V S

    2014-06-01

    To evaluate the effects of infrared-light-emitting diode (LED) during treadmill training on functional performance. Thirty postmenopausal women aged 50-60 years were randomly assigned to one of three groups and successfully completed the full study. The three groups were: (1) the LED group, which performed treadmill training associated with phototherapy (n = 10); (2) the exercise group, which carried out treadmill training only (n = 10); and (3) the sedentary group, which neither performed physical training nor underwent phototherapy (n = 10). Training was performed over a period of 6 months, twice a week for 45 min per session at 85-90% of maximal heart rate, which was obtained during progressive exercise testing. The irradiation parameters were 100 mW, 39 mW/cm(2) and 108 J/cm(2) for 45 min. Quadriceps performance was measured during isokinetic exercise testing at 60°/s and 300°/s. Peak torque did not differ amongst the groups. However, the results showed significantly higher values of power and total work for the LED group (∆ = 21 ± 6 W and ∆ = 634 ± 156 J, p women.

  13. Palpatory method of measuring diastolic blood pressure

    Directory of Open Access Journals (Sweden)

    Dinesh Sahu

    2010-01-01

    Conclusion: The palpatory method would be very useful where frequent blood pressure measurement are being done manually like in wards, in busy OPD, patient on treadmill and also whenever stethoscope is not available. The blood pressure can be measured in noisy environment too.

  14. Fluid Redistribution and Heart Rate in Humans During Whole-Body Tilting, G(z) Centrifugation, and Lower Body Negative Pressure

    Science.gov (United States)

    Watenpaugh, D. E.; Breit, G. A.; Ballard, R. E.; Murthy, G.; Hargens, A. R.

    1994-01-01

    Gravity creates blood pressure gradients which redistribute body fluids towards the feet. Positive G(z) centrifugation and lower body negative pressure (LBNP) have been proposed to simulate these and other effects of gravity during long-term existence in microgravity. We hypothesized that the magnitude of upper-to-lower body fluid redistribution would increase according to the following order: short-arm centrifugation (SAC), long-arm centrifugation (LAC), head-up tilt (HUT), and LBNP. To test this hypothesis, we employed strain gauge plethysmography of the neck, thigh and calf during HUT and supine SAC and LAC up to lG(z) at the feet, and during supine LBNP to 100 mm Hg. Supine 100 mm Hg LBNP generates footward force and produces transmural blood pressures in the foot approximately equal to 1 G(z) (90 deg) HUT. Heart rate was measured via cardiotachometry. Control measurements were made while supine. SAC and LAC elicited similar increases in thigh volume at 1 G(z) (2.3 +/- 0.4 and 2.1 +/- 0.1%, respectively; mean +/- se, n greater than or equal to 7). At 100 mm Hg LBNP, thigh volume increased (3.4 +/- 0.3%) significantly more than during l G(z) centrifugation (p less than 0.05). Surprisingly, due to a paradoxical 0.6% reduction of thigh volume between 0.8 and 1.0 G(z) HUT, thigh volume was increased only 0.6 +/- 0.3% at 1 G(z) HUT. The calf demonstrated similar, although less definitive, responses to the various gravitational stimuli. Neck volume tended to decrease less during HUT than during the other stimuli. Heart rate increased similarly during HUT (18 +/- 2 beats/min) and LAC (12 +/- 2 beats/min), and exhibited still greater elevation during LBNP (29 +/- 4 beats/min), yet did not increase during SAC. These results suggest upright posture activates mechanisms that counteract footward fluid redistribution which are not activated during supine applications of simulated gravity. LAC more closely approximated effects of normal gravity (HUT) than LBNP. Therefore

  15. Effect of treadmill versus overground running on the structure of variability of stride timing.

    Science.gov (United States)

    Lindsay, Timothy R; Noakes, Timothy D; McGregor, Stephen J

    2014-04-01

    Gait timing dynamics of treadmill and overground running were compared. Nine trained runners ran treadmill and track trials at 80, 100, and 120% of preferred pace for 8 min. each. Stride time series were generated for each trial. To each series, detrended fluctuation analysis (DFA), power spectral density (PSD), and multiscale entropy (MSE) analysis were applied to infer the regime of control along the randomness-regularity axis. Compared to overground running, treadmill running exhibited a higher DFA and PSD scaling exponent, as well as lower entropy at non-preferred speeds. This indicates a more ordered control for treadmill running, especially at non-preferred speeds. The results suggest that the treadmill itself brings about greater constraints and requires increased voluntary control. Thus, the quantification of treadmill running gait dynamics does not necessarily reflect movement in overground settings.

  16. Negative pressure driven valence instability of Eu in cubic Eu{sub 0.4}La{sub 0.6}Pd{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Pandey, Abhishek [S N Bose National Centre for Basic Sciences, Block-JD, Sector-III, Salt Lake, Kolkata-700098 (India); Mazumdar, Chandan; Ranganathan, R [Experimental Condensed Matter Physics Division, Saha Institute of Nuclear Physics, 1/AF, Bidhannagar, Kolkata-700064 (India)], E-mail: abhishek.phy@gmail.com, E-mail: chandan.mazumar@saha.ac.in

    2009-05-27

    We report the change in the valency of Eu-ions in the binary intermetallic cubic compound EuPd{sub 3} induced by La doping at rare-earth sites. Doping of La generates negative chemical pressure in the lattice, resulting in a significant increase of the lattice parameter without altering the simple-cubic structure of the compound. Results of dc-magnetic measurements suggest that this increase in the lattice parameter is associated with the valence transition of Eu-ions from Eu{sup 3+} to a mixed-valent state. As Eu{sup 2+}-ions possess a large magnetic moment, this valence transition significantly modifies the magnetic behavior of the compound. In contrast to introducing boron at the vacant body center site of the unit cell to change the valency of Eu-ions, as in the case of EuPd{sub 3}B, our results suggest it can also be altered by doping a rare-earth ion of larger size at the lattice site of Eu in EuPd{sub 3}.

  17. Laparostomy management using the ABThera™ open abdomen negative pressure therapy system in a grade IV open abdomen secondary to acute pancreatitis.

    Science.gov (United States)

    Fitzgerald, James E F; Gupta, Shradha; Masterson, Sarah; Sigurdsson, Helgi H

    2013-04-01

    Wound control in laparostomy for the treatment of intra-abdominal hypertension remains challenging and numerous techniques have been described. We report the first UK experience with a new commercially available device specifically designed to facilitate management of the open abdomen. A 44-year-old gentleman presented with a 3-day history of constant severe epigastric pain and associated vomiting. Amylase was markedly elevated and he was admitted for supportive management of pancreatitis, with subsequent transfer to intensive care due to severe systemic inflammatory syndrome. The patient decompensated, developing intra-abdominal hypertension with renal and respiratory failure. This was successfully managed by performing a laparostomy and using an ABThera™ Open Abdomen Negative Pressure Therapy System (KCI, San Antonio, TX). We describe its use to facilitate wound control, including enteroatmospheric fistula, allowing granulation and eventual restoration of gastrointestinal continuity 383-days after admission. We found the ABThera™ System proved to be a useful treatment adjunct, protecting intra-abdominal contents while removing large volumes of exudate and infected material from within the abdominal cavity. Complex cases such as this remain infrequent and this article provides a summary of our experience, including a review of indications for laparostomy and the underlying basic science in this difficult area. © 2012 The Authors. International Wound Journal © 2012 Blackwell Publishing Ltd and Medicalhelplines.com Inc.

  18. Negative pressure wound therapy using a portable single-use device for free skin grafts on the distal extremity in seven dogs.

    Science.gov (United States)

    Miller, A J; Cashmore, R G; Marchevsky, A M; Havlicek, M; Brown, P M; Fearnside, S M

    2016-09-01

    Retrospective study to describe clinical experience with a portable single-use negative pressure wound therapy device after application of full-thickness meshed skin grafts to wounds on the distal extremities of seven dogs. Seven dogs were treated with portable NPWT after receiving skin grafts; six as the result of tumour resection and one for traumatic injury. Medical records were reviewed and data recorded on patient signalment, cause and location of wound, surgical technique, application and maintenance of portable NPWT, graft survival and outcome, and complications encountered with the system. NPWT was provided for between 4 and 7 days. Five patients were discharged from hospital during the treatment period. Application and maintenance of the portable device was technically easy and no major complications were encountered. Minor complications consisted of fluid accumulation in the evacuation tubing. All dogs achieved 100% graft survival. Application and maintenance of the portable device was technically straightforward. All dogs receiving portable NPWT after transfer of a free skin graft to the distal extremity had a successful outcome. © 2016 Australian Veterinary Association.

  19. Negative pressure wound therapy literature review of efficacy, cost effectiveness, and impact on patients' quality of life in chronic wound management and its implementation in the United kingdom.

    Science.gov (United States)

    Othman, Diaa

    2012-01-01

    This is a paper reviewing the National Health Service (NHS) agenda in relation to the use of Negative Pressure Wound Therapy (NPWT) in chronic wound management and assesses the evidence behind it, its cost effectiveness and the outcome it has on patients' satisfaction and life style. Multiple studies over the last 10 years looking at clinical efficacy of NPWT with its cost effectiveness and the implementation of this service in the UK were reviewed. NPWT has showed a reasonable body of evidence to support its usage in chronic wounds with potential positive outcomes on finance and patients' satisfaction. However, the NHS system shows significant variations in the availability and implementation of this useful tool, depending on care providers and resources availabilities. The paper concluded that the NPWT can be a useful source of cutting down costs of chronic wound managements and saving money by its effect on expediting wound healing, which can address a part of the financial crises facing the NHS, however, has to be considered according to specific case needs. There should also be a national standard for the availability and indication of this tool to assure equal opportunities for different patients in different areas in the country.

  20. A case of deep infection after instrumentation in dorsal spinal surgery: the management with antibiotics and negative wound pressure without removal of fixation.

    Science.gov (United States)

    Dobran, Mauro; Mancini, Fabrizio; Nasi, Davide; Scerrati, Massimo

    2017-07-28

    Until today the role of spinal instrumentation in the presence of a wound infection has been widely discussed and recently many authors leave the hardware in place with appropriate antibiotic therapy. This is a case of a 65-year-old woman suffering from degenerative scoliosis and osteoporotic multiple vertebral collapses treated with posterior dorsolumbar stabilisation with screws and rods. Four months later, skin necrosis and infection appeared in the cranial wound with exposure of the rods. A surgical procedure of debridement of the infected tissue and package with a myocutaneous trapezius muscle flap was performed. One week after surgery, negative pressure wound therapy was started on the residual skin defect. The wound healed after 2 months. The aim of this case report is to focus on the utility of this method even in the case of hardware exposure and infection. This may help avoid removing instrumentation and creating instability. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  1. Ultra pressure liquid chromatography-negative electrospray ionization mass spectrometry determination of twelve halobenzoquinones at ng/L levels in drinking water.

    Science.gov (United States)

    Huang, Rongfu; Wang, Wei; Qian, Yichao; Boyd, Jessica M; Zhao, Yuli; Li, Xing-Fang

    2013-05-07

    We report here the characterization of twelve halobenzoquinones (HBQs) using electrospray ionization (ESI) high resolution quadrupole time-of-flight mass spectrometry. The high resolution negative ESI spectra of the twelve HBQs formed two parent ions, [M + H(+) + 2e(-)], and the radical M(-•). The intensities of these two parent ions are dependent on their chemical structures and on instrumental parameters such as the source temperature and flow rate. The characteristic ions of the HBQs were used to develop an ultra pressure liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method. At the UPLC flow rate (400 μL/min) and under the optimized ESI conditions, eleven HBQs showed the stable and abundant transitions [M + H(+) + 2e(-)] → X(-) (X(-) representing Cl(-), Br(-), or I(-)), while dibromo-dimethyl-benzoquinone (DBDMBQ) showed only the transition of M(-•) → Br(-). The UPLC efficiently separates all HBQs including some HBQ isomers, while the MS/MS offers exquisite limits of detection (LODs) at subng/mL levels for all HBQs except DBDMBQ. Combined with solid phase extraction (SPE), the method LOD is down to ng/L. The results from analysis of authentic samples demonstrated that the SPE-UPLC-MS/MS method is reliable, fast, and sensitive for the identification and quantification of the twelve HBQs in drinking water.

  2. Combing a novel device and negative pressure wound therapy for managing the wound around a colostomy in the open abdomen: A case report.

    Science.gov (United States)

    Sun, Xiaofang; Wu, Shaohan; Xie, Ting; Zhang, Jianping

    2017-12-01

    An open abdomen complicated with small-bowel fistulae becomes a complex wound for local infection, systemic sepsis and persistent soiling irritation by intestinal content. While controlling the fistulae drainage, protecting surrounding skin, healing the wound maybe a challenge. In this paper we described a 68-year-old female was admitted to emergency surgery in general surgery department with severe abdomen pain. Resection part of the injured small bowel, drainage of the intra-abdominal abscess, and fashioning of a colostomy were performed. She failed to improve and ultimately there was tenderness and lot of pus under the skin around the fistulae. The wound started as a 3-cm lesion and progressed to a 6 ×13  (78 cm) around the stoma. In our case we present a novel device for managing colostomy wound combination with negative pressure wound therapy. This tube allows for an effective drainage of small-bowel secretion and a safe build-up of granulation tissue. Also it could be a barrier between the bowel suction point and foam. Management of open abdomen wound involves initial dressing changes, antibiotic use and cutaneous closure. When compared with traditional dressing changes, the NPWT offers several advantages including increased granulation tissue formation, reduction in bacterial colonization, decreased of bowel edema and wound size, and enhanced neovascularization. Copyright © 2017 The Authors. Published by Wolters Kluwer Health, Inc. All rights reserved.

  3. Negative Pressure Wound Therapy Literature Review of Efficacy, Cost Effectiveness, and Impact on Patients' Quality of Life in Chronic Wound Management and Its Implementation in the United Kingdom

    Directory of Open Access Journals (Sweden)

    Diaa Othman

    2012-01-01

    Full Text Available This is a paper reviewing the National Health Service (NHS agenda in relation to the use of Negative Pressure Wound Therapy (NPWT in chronic wound management and assesses the evidence behind it, its cost effectiveness and the outcome it has on patients’ satisfaction and life style. Multiple studies over the last 10 years looking at clinical efficacy of NPWT with its cost effectiveness and the implementation of this service in the UK were reviewed. NPWT has showed a reasonable body of evidence to support its usage in chronic wounds with potential positive outcomes on finance and patients’ satisfaction. However, the NHS system shows significant variations in the availability and implementation of this useful tool, depending on care providers and resources availabilities. The paper concluded that the NPWT can be a useful source of cutting down costs of chronic wound managements and saving money by its effect on expediting wound healing, which can address a part of the financial crises facing the NHS, however, has to be considered according to specific case needs. There should also be a national standard for the availability and indication of this tool to assure equal opportunities for different patients in different areas in the country.

  4. Antimicrobial-impregnated dressing combined with negative-pressure wound therapy increases split-thickness skin graft engraftment: a simple effective technique.

    Science.gov (United States)

    Wu, Cheng-Chun; Chew, Khong-Yik; Chen, Chien-Chang; Kuo, Yur-Ren

    2015-01-01

    Immobilization and adequate surface contact to wounds are critical for skin graft take. Techniques such as the tie-over dressing, cotton bolster, and vacuum-assisted closure are used to address this, but each has its limitations. This study is designed to assess the effect of antimicrobial-impregnated dressing (AMD) combined with negative-pressure wound therapy (NPWT) on skin graft survival. Retrospective case-control study : Patients with chronic or contaminated wounds treated with split-thickness skin graft. A broad spectrum of wounds was included, from causes such as trauma, burns, chronic diabetic ulcers, and infection. Antimicrobial-impregnated dressing, which contains 0.2% polyhexamethylene biguanide, with NPWT MAIN OUTCOME MEASURE:: Success of skin graft : In the AMD group, all skin grafts achieved 100% take without secondary intervention. No infection or graft failure was observed in any patients, and no complications, such as hematoma or seroma formation, were noted, although in the control group partial loss of skin grafts was noted in 3 patients. Infection and inadequate immobilization were thought to be the main reasons. There were no hematoma or seroma formations in the control group. Use of an AMD dressing with NPWT after split-thickness skin grafting can be an effective method to ensure good graft to wound contact and enhances skin graft take in chronic and contaminated wounds.

  5. The Effect of Negative Pressure Wound Therapy With Antiseptic Instillation on Biofilm Formation in a Porcine Model of Infected Spinal Instrumentation.

    Science.gov (United States)

    Singh, Devinder P; Gowda, Arvind U; Chopra, Karan; Tholen, Michael; Chang, Sarah; Mavrophilipos, Vasilios; Semsarzadeh, Nina; Rasko, Yvonne; Holton Iii, Luther

    2017-06-01

    This study evaluates the effect of negative pressure wound therapy with antiseptic instillation (NPWTi) in the clearance of infection and biofilm formation in an in vivo model of infected spinal implants compared to traditional treatment modalities. Five pigs underwent titanium rod implantation of their spinous processes followed by injection of 1 x 106 CFUs/100μL of methicillin-resistant Staphylococcus aureus through the fascia at each site. At 1 week postoperatively, an experimental arm of 3 pigs received NPWTi, and a control arm of 2 pigs received wet-to-dry dressings. The persistence of local infection in the experimental group was compared to the control group using tissue cultures. Biofilm development on spinal implants was evaluated using scanning electron microscopy. Mean bacterial count showed a statistical difference between the experimental and the control groups (P < .05). Scanning electron microscopy revealed the presence of uniform biofilm formation across the surface of control group instrumentation, whereas the experimental group showed interrupted areas between biofilm formations. The authors concluded that NPWTi is associated with decreased bacterial load and biofilm formation compared to wet-to-dry dressings in an in vivo porcine model of infected spinal instrumentation.

  6. Negative pressure wound therapy applied before and after split-thickness skin graft helps healing of Fournier gangrene: a case report (CARE-Compliant).

    Science.gov (United States)

    Ye, Junna; Xie, Ting; Wu, Minjie; Ni, Pengwen; Lu, Shuliang

    2015-02-01

    Fournier gangrene is a rare but highly infectious disease characterized by fulminant necrotizing fasciitis involving the genital and perineal regions. Negative pressure wound therapy (NPWT; KCI USA Inc, San Antonio, TX) is a widely adopted technique in many clinical settings. Nevertheless, its application and effect in the treatment of Fournier gangrene are unclear. A 47-year-old male patient was admitted with an anal abscess followed by a spread of the infection to the scrotum, which was caused by Pseudomonas aeruginosa. NPWT was applied on the surface of the scrotal area and continued for 10 days. A split-thickness skin graft from the scalp was then grafted to the wound, after which, NPWT utilizing gauze sealed with an occlusive dressing and connected to a wall suction was employed for 7 days to secure the skin graft. At discharge, the percentage of the grafted skin alive on the scrotum was 98%. The wound beside the anus had decreased to 4 × 0.5 cm with a depth of 1 cm. Follow-up at the clinic 1 month later showed that both wounds had healed. The patient did not complain of any pain or bleeding, and was satisfied with the outcome. NPWT before and after split-thickness skin grafts is safe, well tolerated, and efficacious in the treatment of Fournier gangrene.

  7. Effect of Negative Pressure Wound Therapy on Cellular Fibronectin and Transforming Growth Factor-β1 Expression in Diabetic Foot Wounds.

    Science.gov (United States)

    Yang, Shao Ling; Zhu, Lv Yun; Han, Rui; Sun, Lei Lei; Dou, Jing Tao

    2017-08-01

    Chronic diabetic foot wounds are a leading cause of amputation, morbidity, and hospitalization for patients with diabetes. Negative-pressure wound therapy (NPWT) can putatively facilitate wound healing, but the underlying mechanisms remain unclear. Cellular fibronectin (cFN) and transforming growth factor-β1 (TGF-β1) play an important role in wound healing. This prospective randomized controlled trial evaluated the effects of NPWT on the production of cFN and the expression of TGF-β1 in diabetic foot wounds of patients. From January 2012 to January 2015, 40 patients with diabetic foot wounds were randomly and equally apportioned to receive either NPWT or advanced moist wound therapy (control) for 7 days. Granulation tissue was harvested before and after treatment. Immunohistochemistry and Western blot were performed to evaluate protein levels of cFN and TGF-β1, and real-time polymerase chain reaction (PCR) to measure corresponding mRNA expressions. NPWT facilitated the expression of cFN and TGF-β1 in diabetic foot wounds. Immunohistochemical analysis revealed higher levels of cFN and TGF-β1 in the NPWT group than in the control group. Western blot and real-time PCR analysis further showed that protein and mRNA levels of cFN or TGF-β1 were higher in the NPWT group than that in the control group ( P diabetic foot ulcers. Level I, randomized controlled study.

  8. Treadmill training improves overground walking economy in Parkinson’s disease: A randomized, controlled pilot study

    Directory of Open Access Journals (Sweden)

    Miguel eFERNANDEZ-DEL-OLMO

    2014-09-01

    Full Text Available Gait disturbances are one of the principal and most incapacitating symptoms of Parkinson’s disease (PD. In addition, walking economy is impaired in PD patients and could contribute to excess fatigue in this population. An important number of studies have shown that treadmill training can improve kinematic parameters in PD patients. However, the effects of treadmill and overground walking on the walking economy remain unknown. The goal of this study was to explore the walking economy changes in response to a treadmill and an overground training program, as well as the differences in the walking economy during treadmill and overground walking. 22 mild PD patients were randomly assigned to a treadmill or overground training group. The training program consisted of 5 weeks (3 sessions/week. We evaluated the energy expenditure of overground walking, before and after each of the training programs. The energy expenditure of treadmill walking (before the program was also evaluated. The treadmill, but not the overground training program, lead to an improvement in the walking economy (the rate of oxygen consumed per distance, during overground walking at a preferred speed in PD patients. In addition, walking on a treadmill required more energy expenditure compared with overground walking at the same speed. This study provides evidence that in mild PD patients, treadmill training is more beneficial compared with that of walking overground, leading to a greater improvement in the walking economy. This finding is of clinical importance for the therapeutic administration of exercise in Parkinson’s disease.

  9. Commercial Motion Sensor Based Low-Cost and Convenient Interactive Treadmill

    Directory of Open Access Journals (Sweden)

    Jonghyun Kim

    2015-09-01

    Full Text Available Interactive treadmills were developed to improve the simulation of overground walking when compared to conventional treadmills. However, currently available interactive treadmills are expensive and inconvenient, which limits their use. We propose a low-cost and convenient version of the interactive treadmill that does not require expensive equipment and a complicated setup. As a substitute for high-cost sensors, such as motion capture systems, a low-cost motion sensor was used to recognize the subject’s intention for speed changing. Moreover, the sensor enables the subject to make a convenient and safe stop using gesture recognition. For further cost reduction, the novel interactive treadmill was based on an inexpensive treadmill platform and a novel high-level speed control scheme was applied to maximize performance for simulating overground walking. Pilot tests with ten healthy subjects were conducted and results demonstrated that the proposed treadmill achieves similar performance to a typical, costly, interactive treadmill that contains a motion capture system and an instrumented treadmill, while providing a convenient and safe method for stopping.

  10. Rhythm perturbations in acoustically paced treadmill walking after stroke.

    Science.gov (United States)

    Roerdink, Melvyn; Lamoth, Claudine J C; van Kordelaar, Joost; Elich, Peter; Konijnenbelt, Manin; Kwakkel, Gert; Beek, Peter J

    2009-09-01

    In rehabilitation, acoustic rhythms are often used to improve gait after stroke. Acoustic cueing may enhance gait coordination by creating a stable coupling between heel strikes and metronome beats and provide a means to train the adaptability of gait coordination to environmental changes, as required in everyday life ambulation. To examine the stability and adaptability of auditory-motor synchronization in acoustically paced treadmill walking in stroke patients. Eleven stroke patients and 10 healthy controls walked on a treadmill at preferred speed and cadence under no metronome, single-metronome (pacing only paretic or nonparetic steps), and double-metronome (pacing both footfalls) conditions. The stability of auditory-motor synchronization was quantified by the variability of the phase relation between footfalls and beats. In a separate session, the acoustic rhythms were perturbed and adaptations to restore auditory-motor synchronization were quantified. For both groups, auditory-motor synchronization was more stable for double-metronome than single-metronome conditions, with stroke patients exhibiting an overall weaker coupling of footfalls to metronome beats than controls. The recovery characteristics following rhythm perturbations corroborated the stability findings and further revealed that stroke patients had difficulty in accelerating their steps and instead preferred a slower-step response to restore synchronization. In gait rehabilitation practice, the use of acoustic rhythms may be more effective when both footfalls are paced. In addition, rhythm perturbations during acoustically paced treadmill walking may not only be employed to evaluate the stability of auditory-motor synchronization but also have promising implications for evaluation and training of gait adaptations in neurorehabilitation practice.

  11. Treadmill training and body weight support for walking after stroke.

    Science.gov (United States)

    Mehrholz, Jan; Thomas, Simone; Elsner, Bernhard

    2017-08-17

    Treadmill training, with or without body weight support using a harness, is used in rehabilitation and might help to improve walking after stroke. This is an update of the Cochrane review first published in 2003 and updated in 2005 and 2014. To determine if treadmill training and body weight support, individually or in combination, improve walking ability, quality of life, activities of daily living, dependency or death, and institutionalisation or death, compared with other physiotherapy gait-training interventions after stroke. The secondary objective was to determine the safety and acceptability of this method of gait training. We searched the Cochrane Stroke Group Trials Register (last searched 14 February 2017), the Cochrane Central Register of Controlled Trials (CENTRAL) and the Database of Reviews of Effects (DARE) (the Cochrane Library 2017, Issue 2), MEDLINE (1966 to 14 February 2017), Embase (1980 to 14 February 2017), CINAHL (1982 to 14 February 2017), AMED (1985 to 14 February 2017) and SPORTDiscus (1949 to 14 February 2017). We also handsearched relevant conference proceedings and ongoing trials and research registers, screened reference lists, and contacted trialists to identify further trials. Randomised or quasi-randomised controlled and cross-over trials of treadmill training and body weight support, individually or in combination, for the treatment of walking after stroke. Two review authors independently selected trials, extracted data, and assessed risk of bias and methodological quality. The primary outcomes investigated were walking speed, endurance, and dependency. We included 56 trials with 3105 participants in this updated review. The average age of the participants was 60 years, and the studies were carried out in both inpatient and outpatient settings. All participants had at least some walking difficulties and many could not walk without assistance. Overall, the use of treadmill training did not increase the chances of walking

  12. Simultaneous low level treadmill exercise and intravenous dipyridamole stress thallium imaging

    International Nuclear Information System (INIS)

    Casale, P.N.; Guiney, T.E.; Strauss, H.W.; Boucher, C.A.

    1988-01-01

    Intravenous dipyridamole-thallium imaging unmasks ischemia in patients unable to exercise adequately. However, some of these patients can perform limited exercise, which, if added, may provide useful information. Treadmill exercise combined with dipyridamole-thallium imaging was performed in 100 patients and results compared with those of 100 other blindly age- and sex-matched patients who received dipyridamole alone. Exercise began after completion of the dipyridamole infusion. Mean +/- 1 standard deviation peak heart rate (109 +/- 19 vs 83 +/- 12 beats/min, p less than 0.0001) and peak systolic and diastolic blood pressure (146 +/- 28/77 +/- 14 vs 125 +/- 24/68 +/- 11 mm Hg, p less than 0.0001) were higher in the exercise group compared with the nonexercise group. There was no difference in the occurrence of chest pain, but more patients in the exercise group developed ST-segment depression (26 vs 12%, p less than 0.0001). The exercise group had fewer noncardiac side effects (4 vs 12%, p less than 0.01) and a higher target (heart) to background (liver) count ratio (2.1 +/- 0.7 vs 1.2 +/- 0.3; p less than 0.01), due to fewer liver counts. There were no deaths, myocardial infarctions or sustained arrhythmias in either group. Combined treadmill exercise and dipyridamole testing is safe, associated with fewer noncardiac side effects, a higher target to background ratio and a higher incidence of clinical electrocardiographic ischemia than dipyridamole alone. Therefore, it is recommended whenever possible

  13. Inactivation of gram-negative bacteria in milk and banana juice by hen egg white and lambda lysozyme under high hydrostatic pressure.

    Science.gov (United States)

    Nakimbugwe, Dorothy; Masschalck, Barbara; Anim, Grace; Michiels, Chris W

    2006-10-15

    The effect of hen egg white lysozyme (HEWL) and bacteriophage lambda lysozyme (LaL) in combination with high pressure (HP) treatment on the inactivation of four gram-negative bacteria (Escherichia coli O157:H7, Shigella flexneri, Yersinia enterocolitica and Salmonella typhimurium), was studied in skim milk (pH 6.8; a(w) 0.997) and in banana juice (pH 3.8; a(w) 0.971). In the absence of lysozymes, S. flexneri was more sensitive to HP in milk than in banana juice, while the opposite was observed for the other three bacteria. In combination with HP treatment, LaL was more effective than HEWL on all bacteria in both milk and banana juice. Depending on the bacteria, inactivation levels in banana juice were increased from 0.4-2.7 log units by HP treatment alone to 3.6-6.5 log units in the presence of 224 U/ml LaL. Bacterial inactivation in milk was also enhanced by LaL but only by 0.5-2.1 log units. Under the experimental conditions used, LaL was more effective in banana juice than in milk, while the effectiveness of HEWL under the same conditions was not significantly affected by the food matrix. This effect could be ascribed to the low pH of the banana juice since LaL was also more effective on E. coli in buffer at pH 3.8 than at pH 6.8. Since neither LaL nor HEWL are enzymatically active at pH 3.8, we analysed bacterial lysis after HP treatment in the presence of these enzymes, and found that inactivation proceeds through a non-lytic mechanism at pH 3.8 and a lytic mechanism at pH 6.8. Based on these results, LaL may offer interesting perspectives for use as an extra hurdle in high pressure food preservation.

  14. Negative Pressure Wound Therapy With Instillation (NPWTi) Better Reduces Post-debridement Bioburden in Chronically Infected Lower Extremity Wounds Than NPWT Alone.

    Science.gov (United States)

    Goss, S G; Schwartz, J A; Facchin, F; Avdagic, E; Gendics, C; Lantis, J C

    2012-12-01

    An overabundance of bacteria in the chronic wound plays a significant role in the decreased ability for primary closure. One means of decreasing the bioburden in a wound is to operatively debride the wound for wound bed optimization prior to application of other therapy, such as Negative Pressure Wound Therapy (NPWT). We undertook a prospective pilot study to assess the efficacy of wound bed preparation for a standard algorithm (sharp surgical debridement followed by NPWT) versus one employing sharp surgical debridement followed by Negative Pressure Wound Therapy with Instillation (NPWTi). Thirteen patients, corresponding to 16 chronic lower leg and foot wounds were taken to the operating room for debridement. The patients were sequentially enrolled in 2 treatment groups: the first receiving treatment with operative debridement followed by 1 week of NPWT with the instillation of quarter strength bleach solution; the other receiving a standard algorithm consisting of operative debridement and 1 week of NPWT. Quantitative cultures were taken pre-operatively after sterile preparation and draping of the wound site (POD # 0, pre-op), post-operatively once debridement was completed (POD # 0, post-op), and on post-operative day 7 after operative debridement (POD # 7, post-op). After operative debridement (post-operative day 0) there was a mean of 3 (±1) types of bacteria per wound. The mean CFU/gram tissue culture was statistically greater - 3.7 × 10(6) (±4 × 10(6)) in the NPWTi group, while in the standard group (NPWT) the mean was 1.8 × 10(6) (±2.36 × 10(6)) CFU/gram tissue culture (p = 0.016); at the end of therapy there was no statistical difference between the two groups (p = 0.44). Wounds treated with NPWTi had a mean of 2.6 × 10(5) (±3 × 10(5)) CFU/gram of tissue culture while wounds treated with NPWT had a mean of 2.79 × 10(6) (±3.18 × 10(6)) CFU/gram of tissue culture (p = 0.43). The mean absolute reduction in bacteria for the

  15. Comparison of Negative Pressure Wound Therapy Using Vacuum-Assisted Closure with Advanced Moist Wound Therapy in the Treatment of Diabetic Foot Ulcers.

    Science.gov (United States)

    Sajid, Muhammad Tanveer; Mustafa, Qurat ul Ain; Shaheen, Neelofar; Hussain, Syed Mukarram; Shukr, Irfan; Ahmed, Muhammad

    2015-11-01

    To evaluate the clinical efficacy of Negative Pressure Wound Therapy (NPWT) using Vacuum Assisted Closure (VAC) compared with Advanced Moist Wound Therapy (AMWT) to treat Diabetic Foot Ulcer (DFU). Randomized control trial. Surgical Department, Combined Military Hospital (CMH) / Military Hospital (MH), Rawalpindi, from November 2010 to June 2012. The study consisted of 278 patients, with 139 patients each in Group 'A' and 'B', who were subjected to AMWT and NPWT, respectively. Wound was assessed digitally every week for 2 weeks. Wound dimension and surface area were determined using University of Texas Health Centre at San Antonio (UTHCSA) image tool version 3.0. Efficacies of AMWT and NPWT were compared in terms of reduction in wound area over 2 weeks. Mean age of presentation in group A was 55.88 ± 10.97 years while in group B, it was 56.83 ± 11.3 (p=0.48). Mean duration of diabetes at presentation was 15.65 ± 4.86 and 15.96 ± 5.79 years in group A and B, respectively (p=0.74). Majority of patients had Wagner's grade 2 ulcer (82% in group A and 87.8% in group B, p= 0.18). Initial wound size in group A was 15.07 ± 2.92 cm2 and in group B 15.09 ± 2.81 cm2 (p = 0.95). Wound size measured after 2 weeks, treatment was in group A13.70 ± 2.92 cm2 and in group B 11.53 ± 2.78 cm2 (p VAC was more efficacious than AMWT in the management of diabetic foot ulcers.

  16. Does treatment of split-thickness skin grafts with negative-pressure wound therapy improve tissue markers of wound healing in a porcine experimental model?

    Science.gov (United States)

    Ward, Christopher; Ciraulo, David; Coulter, Michael; Desjardins, Steven; Liaw, Lucy; Peterson, Sarah

    2012-08-01

    Negative-pressure wound therapy (NPWT) has been used for to treat wounds for more than 15 years and, more recently, has been used to secure split-thickness skin grafts. There are some data to support this use of NPWT, but the actual mechanism by which NPWT speeds healing or improves skin graft take is not entirely known. The purpose of this project was to assess whether NPWT improved angiogenesis, wound healing, or graft survival when compared with traditional bolster dressings securing split-thickness skin grafts in a porcine model. We performed two split-thickness skin grafts on each of eight 30 kg Yorkshire pigs. We took graft biopsies on postoperative days 2, 4, 6, 8, and 10 and submitted the samples for immunohistochemical staining, as well as standard hematoxylin and eosin staining. We measured the degree of vascular ingrowth via immunohistochemical staining for von Willenbrand's factor to better identify blood vessel epithelium. We determined the mean cross-sectional area of blood vessels present for each representative specimen, and then compared the bolster and NPWT samples. We also assessed each graft for incorporation and survival at postoperative day 10. Our analysis of the data revealed that there was no statistically significant difference in the degree of vascular ingrowth as measured by mean cross-sectional capillary area (p = 0.23). We did not note any difference in graft survival or apparent incorporation on a macroscopic level, although standard hematoxylin and eosin staining indicated that microscopically, there seemed to be better subjective graft incorporation in the NPWT samples and a nonsignificant trend toward improved graft survival in the NPWT group. We were unable to demonstrate a significant difference in vessel ingrowth when comparing NPWT and traditional bolster methods for split-thickness skin graft fixation. More studies are needed to elucidate the manner by which NPWT exerts its effects and the true clinical magnitude of these

  17. Health Technology Assessment of the Negative Pressure Wound Therapy for the treatment of acute and chronic wounds: efficacy, safety, cost effectiveness, organizational and ethical impact

    Directory of Open Access Journals (Sweden)

    Paolo Giorgi Rossi

    2012-06-01

    Full Text Available

    Background: the aim of the study was to assess the safety, efficacy and cost-effectiveness of negative Pressure wound therapy (nPT for people with chronic and acute wounds.

    Methods: the scope and the final draft of the report have been submitted to the stakeholders (producers, payers and patients. safety issues were addressed through a systematic review of the meta-literature. efficacy was addressed through a systematic review and meta-analysis of randomized controlled trials (rcTs comparing nPT and other standard therapies in patients with chronic or acute lesions. cost-consequence was analyzed through a systematic review of the existing studies.

    Results: we retrieved 19 studies, 13 of which were included in the meta-analysis. Many studies had biases that may have resulted in a better performance for nPT. nPT showed: a slightly shorter healing time (-10.4 days, p=0.001, with no heterogeneity, apart from one small study with very positive results, and 40% more patients healed (p=0.002, no heterogeneity.We identified 15 original research papers on nPT costs and cost per outcome. The costs-per-patient- treated varied from +29% to -60%, with several studies reporting savings for nPT.

    Conclusions: despite serious methodological flaws, the body of evidence available was sufficient to prove some clinical benefit of nPT in severe chronic and acute wound treatment. There is a need for independent and contextualized cost analyses....

  18. Negative pressure wound therapy, staged excision and definitive closure with split-thickness skin graft for axillary hidradenitis suppurativa: a retrospective study.

    Science.gov (United States)

    Pearce, F B; Richardson, K A

    2017-01-02

    Bilateral axillary hidradenitis is a chronic, suppurative, and scarring disease that is most effectively treated by complete excision of all hair-bearing tissues. We assessed our staged procedure for excision and placement of a split-thickness skin graft for bilateral axillary hidradenitis in terms of costs, outcomes, and timing of excision. An IRB approved retrospective case analysis was performed on patients that underwent bilateral axillary hidradenitis skin excision with eventual placement of split-thickness skin grafting using the current LSUHSC/University Health hidradenitis surgical treatment protocol. Using ICD-9 codes (705.83) and CPT codes (11041, 11042, 11451, 11600, 11601, 11602, 11603, 11604) we reviewed cases performed at our institution from 1 January 2008 to 24 Febuary 2014 and we selected patients based on bilateral axillary involvement (alone) and >1 year history of active disease. Patients were excluded if resection of tissue encompassed regions outside of the immediately adjacent axillary. A total of seven patients matching criteria for bilateral axillary hidradenitis were selected for analysis. Clinical course, cost and surgical techniques were assessed. Of the seven patients, six required admission throughout their treatment due to lack of funding making use of negative pressure wound therapy at home not possible. These patients stayed an average of 10 days with a mean hospital charge of $35,178 and a mean hospital provider charge of $10,019. No recurrence was demonstrated. All patients attained full range of motion, post grafting. No patient required a further operation due to graft failure. Split-thickness skin grafting without use of bilayer dermal regenerative templates yielded definitive results with acceptable cosmesis and functionality, without the added cost of treatments such as a bilayer dermal regenerative template.

  19. Comparison of negative pressure wound therapy using vacuum-assisted closure with advanced moist wound therapy in the treatment of diabetic foot ulcers

    International Nuclear Information System (INIS)

    Sajid, M.T.; Mustafa, Q.U.A.

    2015-01-01

    Objective: To evaluate the clinical efficacy of Negative Pressure Wound Therapy (NPWT) using Vacuum Assisted Closure (VAC) compared with Advanced Moist Wound Therapy (AMWT) to treat Diabetic Foot Ulcer (DFU). Study Design: Randomized control trial. Place and Duration of Study: Surgical Department, Combined Military Hospital (CMH) / Military Hospital (MH), Rawalpindi, from November 2010 to June 2012. Methodology: The study consisted of 278 patients, with 139 patients each in Group A and B, who were subjected to AMWT and NPWT, respectively. Wound was assessed digitally every week for 2 weeks. Wound dimension and surface area were determined using University of Texas Health Centre at San Antonio (UTHCSA) image tool version 3.0. Efficacies of AMWT and NPWT were compared in terms of reduction in wound area over 2 weeks. Results: Mean age of presentation in group Awas 55.88 10.97 years while in group B, it was 56.83 ± 11.3 (p=0.48). Mean duration of diabetes at presentation was 15.65 ± 4.86 and 15.96 ± 5.79 years in group A and B, respectively (p=0.74). Majority of patients had Wagner's grade 2 ulcer (82% in group A and 87.8% in group B, p= 0.18). Initial wound size in group A was 15.07 ± 2.92 cm2and in group B 15.09 ± 2.81 cm2(p = 0.95). Wound size measured after 2 weeks, treatment was in group A13.70 ± 2.92 cm2 and in group B 11.53 ± 2.78 cm2 (p < 0.001). Wound area reduction in both groups revealed statistically significant faster healing in group B as compared to group A(p < 0.001). Conclusion: NPWT using VAC was more efficacious than AMWT in the management of diabetic foot ulcers. (author)

  20. Use of collagenase ointment in conjunction with negative pressure wound therapy in the care of diabetic wounds: a case series of six patients

    Directory of Open Access Journals (Sweden)

    John D. Miller

    2015-01-01

    Full Text Available Background: Diabetic wounds with additional comorbidities are costly, time intensive, and difficult to heal. Often, multiple modalities may be necessary to achieve wound resolution, relying on the synergistic advantage of each therapy to affect wound healing. The selectivity of Clostridium collagenase is physiologically effective at degrading non-viable collagen fibers while preserving living collagen tissue. Additionally, negative pressure wound therapy (NPWT has long been used to aid wound healing while concurrently depreciating biological wound burden time. Methods: Six patients were selected from those appearing to our university based limb salvage service. Inclusion criteria included patients with a recurrent mixed fibrotic and granular wound base, in which NPWT was indicated, without exclusion criteria. Patients enrolled were administered clostridial collagenase ointment at each regularly scheduled NPWT dressing change. Patients were followed until healing, with visual representations of wound progression and time to full healing recorded. Results: Tandem application of these therapies appeared to expedite wound healing by clearing degenerative fibrous tissue and expediting wound granulation without additional complication. Unfortunately, not all patients were able to reach full healing; with two patients experiencing ulcer recurrence, likely a result of their significant comorbid nature. Conclusion: In our experience, we have noticed a specific subgroup of patients who benefit greatly when collagenase enzymatic debridement therapy is combined with NPWT. It is our belief that this combination therapy combines the molecular clearing of non-viable collagen with the wound granulation necessary to advance complex wounds to the next step in healing despite the current paucity in literature discussing this specific pairing.

  1. Basal electric and magnetic fields of celestial bodies come from positive-negative charge separation caused by gravitation of quasi-Casimir pressure in weak interaction

    Science.gov (United States)

    Chen, Shao-Guang

    According to f =d(mv)/dt=m(dv/dt)+ v(dm/dt), a same gravitational formula had been de-duced from the variance in physical mass of QFT and from the variance in mass of inductive energy-transfer of GR respectively: f QF T = f GR = -G (mM/r2 )((r/r)+(v/c)) when their interaction-constants are all taken the experimental values (H05-0029-08, E15-0039-08). f QF T is the quasi-Casimir pressure. f GR is equivalent to Einstein's equation, then more easy to solve it. The hypothesis of the equivalent principle is not used in f QF T , but required by f GR . The predictions of f QF T and f GR are identical except that f QF T has quantum effects but f GR has not and f GR has Lense-Thirring effect but f QF T has not. The quantum effects of gravitation had been verified by Nesvizhevsky et al with the ultracold neutrons falling in the earth's gravitational field in 2002. Yet Lense-Thirring effect had not been measured by GP-B. It shows that f QF T is essential but f GR is phenomenological. The macro-f QF T is the statistic average pressure collided by net virtual neutrinos ν 0 flux (after self-offset in opposite directions) and in direct proportion to the mass. But micro-f QF T is in direct proportion to the scattering section. The electric mass (in inverse proportion to de Broglie wavelength λ) far less than nucleonic mass and the electric scattering section (in direct proportion to λ2 ) far large than that of nucleon, then the net ν 0 flux pressure exerted to electron far large than that to nucleon and the electric displacement far large than that of nucleon, it causes the gravitational polarization of positive-negative charge center separation. Because the gravity far less than the electromagnetic binding force, in atoms the gravitational polarization only produces a little separation. But the net ν 0 flux can press a part freedom electrons in plasma of ionosphere into the earth's surface, the static electric force of redundant positive ions prevents electrons from further

  2. Partial Body Weight-Supported Treadmill Training in Spinocerebellar Ataxia.

    Science.gov (United States)

    de Oliveira, Laura Alice Santos; Martins, Camilla Polonini; Horsczaruk, Carlos Henrique Ramos; da Silva, Débora Cristina Lima; Vasconcellos, Luiz Felipe; Lopes, Agnaldo José; Meira Mainenti, Míriam Raquel; Rodrigues, Erika de Carvalho

    2018-01-01

    The motor impairments related to gait and balance have a huge impact on the life of individuals with spinocerebellar ataxia (SCA). Here, the aim was to assess the possibility of retraining gait, improving cardiopulmonary capacity, and challenging balance during gait in SCA using a partial body weight support (BWS) and a treadmill. Also, the effects of this training over functionality and quality of life were investigated. Eight SCA patients were engaged in the first stage of the study that focused on gait training and cardiovascular conditioning. From those, five took part in a second stage of the study centered on dynamic balance training during gait. The first and second stages lasted 8 and 10 weeks, respectively, both comprising sessions of 50 min (2 times per week). The results showed that gait training using partial BWS significantly increased gait performance, treadmill inclination, duration of exercise, and cardiopulmonary capacity in individuals with SCA. After the second stage, balance improvements were also found. Combining gait training and challenging tasks to the postural control system in SCA individuals is viable, well tolerated by patients with SCA, and resulted in changes in capacity for walking and balance.

  3. The War on Drugs in Colombia: The Environment, the Treadmill of Destruction and Risk-Transfer Militarism

    Directory of Open Access Journals (Sweden)

    Chad L. Smith

    2015-08-01

    Full Text Available Ecological damage, including global climate change, is commonly connected to practices and behaviors associated with economic activity and the Treadmill of Production (ToP. Less attention is paid to the connection between the military and environmental degradation, but recently the Treadmill of Destruction (ToD has been documented as a global phenomenon with negative environmental effects. The ToD directly and indirectly contributes to environmental problems on many fronts, but one of the least obvious means by which the U.S. military influences the environment is through its policies supporting the "war on drugs. " The U.S. military aids Latin American countries, particularly Colombia, in the war on drugs in a number of capacities, including military support and training, weaponry, fumigation of crops, and logistical and surveillance support. The effort of the United States to curb the proliferation of illegal drug crops in Colombia is the most direct role that the military has played in this effort. Within the context of the "war on drugs" the United States is now engaged in risk-transfer militarism in which the consequences of this military action are borne by the Global South. We document the scope, magnitude, and consequences of the ToD in the war on drugs and the ways it negatively impacts the environment. Our argument reframes the ToD by emphasizing the role of risk-transfer militarism within the emergence of "new" wars as represented in the case of Colombia.

  4. Increasing physical activity in office workers ? the Inphact Treadmill study; a study protocol for a 13-month randomized controlled trial of treadmill workstations

    OpenAIRE

    Bergman, Frida; Boraxbekk, Carl-Johan; Wennberg, Patrik; S?rlin, Ann; Olsson, Tommy

    2015-01-01

    Background Sedentary behaviour is an independent risk factor for mortality and morbidity, especially for type 2 diabetes. Since office work is related to long periods that are largely sedentary, it is of major importance to find ways for office workers to engage in light intensity physical activity (LPA). The Inphact Treadmill study aims to investigate the effects of installing treadmill workstations in offices compared to conventional workstations. Methods/Design A two-arm, 13-month, randomi...

  5. Compliance of Children with Moderate to Severe Intellectual Disability to Treadmill Walking: A Pilot Study

    Science.gov (United States)

    Vashdi, E.; Hutzler, Y.; Roth, D.

    2008-01-01

    Background: Individuals with Intellectual Disability (ID) exhibit reduced levels of compliance to exercise, including treadmill walking. The purpose of this study was to measure the effects of several training conditions on compliance to participation in treadmill walking of children with moderate to severe ID. Method: Criteria for compliance were…

  6. Negative pressure wound treatment improves Acute Physiology and Chronic Health Evaluation II score in mediastinitis allowing a successful elective pectoralis muscle flap closure: six-year experience of a single protocol.

    Science.gov (United States)

    Salica, Andrea; Weltert, Luca; Scaffa, Raffaele; Guerrieri Wolf, Lorenzo; Nardella, Saverio; Bellisario, Alessandro; De Paulis, Ruggero

    2014-11-01

    Optimal management of poststernotomy mediastinitis is controversial. Negative pressure wound treatment improves wound environment and sternal stability with low surgical invasiveness. Our protocol was based on negative pressure followed by delayed surgical closure. The aim of this study was to provide the results at early follow-up and to identify the risk factors for adverse outcome. In 5400 cardiac procedures, 44 consecutive patients with mediastinitis were enrolled in the study. Mediastinitis treatment was based on urgent debridement and negative pressure as the first-line approach. After wound sterilization, chest closure was achieved by elective pectoralis muscle advancement flap. Each patient's hospital data were collected prospectively. Variables included patient demographics and clinical and biological data. Acute Physiology and Chronic Health Evaluation (APACHE) II score was calculated at the time of diagnosis and 48 hours after debridement. Focus outcome measures were mediastinitis-related death and need for reintervention after pectoralis muscle closure. El Oakley type I and type IIIA mediastinitis were the most frequent types (63.6%). Methicillin-resistant Staphylococcus aureus was present in 25 patients (56.8%). Mean APACHE II score was 19.4±4 at the time of diagnosis, and 30 patients (68.2%) required intensive care unit transfer before surgical debridement. APACHE II score improved 48 hours after wound debridement and negative pressure application (mean value, 19.4±4 vs 7.2±2; P=.005) independently of any other variables included in the study. One patient in septic shock at the time of diagnosis died (2.2%). Negative pressure promotes a significant improvement in clinical status according to APACHE II score and allows a successful elective surgical closure. Copyright © 2014 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

  7. A user-driven treadmill control scheme for simulating overground locomotion.

    Science.gov (United States)

    Kim, Jonghyun; Stanley, Christopher J; Curatalo, Lindsey A; Park, Hyung-Soon

    2012-01-01

    Treadmill-based locomotor training should simulate overground walking as closely as possible for optimal skill transfer. The constant speed of a standard treadmill encourages automaticity rather than engagement and fails to simulate the variable speeds encountered during real-world walking. To address this limitation, this paper proposes a user-driven treadmill velocity control scheme that allows the user to experience natural fluctuations in walking velocity with minimal unwanted inertial force due to acceleration/deceleration of the treadmill belt. A smart estimation limiter in the scheme effectively attenuates the inertial force during velocity changes. The proposed scheme requires measurement of pelvic and swing foot motions, and is developed for a treadmill of typical belt length (1.5 m). The proposed scheme is quantitatively evaluated here with four healthy subjects by comparing it with the most advanced control scheme identified in the literature.

  8. Effects of treadmill running on rat gastrocnemius function following botulinum toxin A injection.

    Science.gov (United States)

    Tsai, Sen-Wei; Chen, Chun-Jung; Chen, Hsiao-Lin; Chen, Chuan-Mu; Chang, Yin-Yi

    2012-02-01

    Exercise can improve and maintain neural or muscular function, but the effects of exercise in physiological adaptation to paralysis caused by botulinum toxin A has not been well studied. Twenty-four rats were randomly assigned into control and treadmill groups. The rats assigned to the treadmill group were trained on a treadmill three times per week with the running speed set at 15 m/min. The duration of training was 20 min/session. Muscle strength, nerve conduction study and sciatic functional index (SFI) were used for functional analysis. Treadmill training improved the SFI at 2, 3, and 4 weeks (p = 0.01, 0.004, and 0.01, respectively). The maximal contraction force of the gastrocnemius muscle in the treadmill group was greater than in the control group (p properties of muscle contraction strength, CMAP amplitude, and the recovery of SFI. Copyright © 2011 Orthopaedic Research Society.

  9. Treadmill workstations: the effects of walking while working on physical activity and work performance.

    Science.gov (United States)

    Ben-Ner, Avner; Hamann, Darla J; Koepp, Gabriel; Manohar, Chimnay U; Levine, James

    2014-01-01

    We conducted a 12-month-long experiment in a financial services company to study how the availability of treadmill workstations affects employees' physical activity and work performance. We enlisted sedentary volunteers, half of whom received treadmill workstations during the first two months of the study and the rest in the seventh month of the study. Participants could operate the treadmills at speeds of 0-2 mph and could use a standard chair-desk arrangement at will. (a) Weekly online performance surveys were administered to participants and their supervisors, as well as to all other sedentary employees and their supervisors. Using within-person statistical analyses, we find that overall work performance, quality and quantity of performance, and interactions with coworkers improved as a result of adoption of treadmill workstations. (b) Participants were outfitted with accelerometers at the start of the study. We find that daily total physical activity increased as a result of the adoption of treadmill workstations.

  10. [Kinetics of heifers and cows walking on an instrumented treadmill].

    Science.gov (United States)

    Nuss, K; Waldern, N M; Weishaupt, M A; Wiestner, T

    2015-01-01

    Kinetic data of stride characteristics and ground reaction forces of cattle become increasingly important as automated lameness detection may be installed in dairy cow housing systems in the future. Therefore, sound heifers and cows were measured on an instrumented treadmill to collect such basic data. Nine heifers and 10 cows were trained to walk on an instrumented treadmill. Vertical ground reaction forces as well as step and stride timing and length variables were measured for all limbs simultaneously. On average, 16 stride cycles in cows and 24 strides in heifers were analysed in each case. The cows walked on the treadmill at an average speed of 1.2 ± 0.05 m/s (mean ± standard deviation), with a stride rate of 43.0 ± 1.9/min and a stride length of 1.68 ± 0.1 m. The heifers had average values of 1.3 ± 0.04 m/s, 53.7 ± 2.2/min and 1.49 ± 0.05 m, respectively. The stance duration relative to stride duration (the duty factor) was for the cows significantly longer in the forelimbs (67%) than in the hind limbs (64%). Force-time-curves of all limbs showed two peaks, one after landing (FP1) and another during push off (FP2). Vertical ground reaction force was highest for FP1 in the hind limbs, but for FP2 in the forelimbs. At all limbs, force minimum between the peaks occurred shortly before midstance. The vertical impulse carried by both forelimbs amounted to 53.7% of the total stride impulse in cows and to 55.0% in heifers. The location of the centre of body mass varied during the stride cycle but was always located more towards the front limbs. Cows and heifers showed a symmetrical walk with minimal intra-individual variations. Relative stride impulse of the front limbs was higher than that of the hind limbs. Peak vertical force in the hind limbs was highest at landing and in the forelimbs at push off. The present study offers kinetic data of sound cows and heifers which might be helpful as guidelines for automated systems for lameness detection in cattle.

  11. Experimental evidence for negative turgor pressure in small leaf cells of Robinia pseudoacacia L versus large cells of Metasequoia glyptostroboides Hu et W.C. Cheng. 2. Höfler diagrams below the volume of zero turgor and the theoretical implication for pressure-volume curves of living cells.

    Science.gov (United States)

    Yang, Dongmei; Li, Junhui; Ding, Yiting; Tyree, Melvin T

    2017-03-01

    The physiological advantages of negative turgor pressure, P t , in leaf cells are water saving and homeostasis of reactants. This paper advances methods for detecting the occurrence of negative P t in leaves. Biomechanical models of pressure-volume (PV) curves predict that negative P t does not change the linearity of PV curve plots of inverse balance pressure, P B , versus relative water loss, but it does predict changes in either the y-intercept or the x-intercept of the plots depending on where cell collapse occurs in the P B domain because of negative P t . PV curve analysis of Robinia leaves revealed a shift in the x-intercept (x-axis is relative water loss) of PV curves, caused by negative P t of palisade cells. The low x-intercept of the PV curve was explained by the non-collapse of palisade cells in Robinia in the P B domain. Non-collapse means that P t smoothly falls from positive to negative values with decreasing cell volume without a dramatic change in slope. The magnitude of negative turgor in non-collapsing living cells was as low as -1.3 MPa and the relative volume of the non-collapsing cell equaled 58% of the total leaf cell volume. This study adds to the growing evidence for negative P t . © 2016 John Wiley & Sons Ltd.

  12. High pressure studies of A2Mo3O12 negative thermal expansion materials (A2=Al2, Fe2, FeAl, AlGa)

    International Nuclear Information System (INIS)

    Young, Lindsay; Gadient, Jennifer; Gao, Xiaodong; Lind, Cora

    2016-01-01

    High pressure powder X-ray diffraction studies of several A 2 Mo 3 O 12 materials (A 2 =Al 2 , Fe 2 , FeAl, and AlGa) were conducted up to 6–7 GPa. All materials adopted a monoclinic structure under ambient conditions, and displayed similar phase transition behavior upon compression. The initial isotropic compressibility first became anisotropic, followed by a small but distinct drop in cell volume. These patterns could be described by a distorted variant of the ambient pressure polymorph. At higher pressures, a distinct high pressure phase formed. Indexing results confirmed that all materials adopted the same high pressure phase. All changes were reversible on decompression, although some hysteresis was observed. The similarity of the high pressure cells to previously reported Ga 2 Mo 3 O 12 suggested that this material undergoes the same sequence of transitions as all materials investigated in this paper. It was found that the transition pressures for all phase changes increased with decreasing radius of the A-site cations. - Graphical abstract: Overlay of variable pressure X-ray diffraction data of Al 2 Mo 3 O 12 collected in a diamond anvil cell. Both subtle and discontinuous phase transitions are clearly observed. - Highlights: • The high pressure behavior of A 2 Mo 3 O 12 (A=Al, Fe, (AlGa), (AlFe)) was studied. • All compounds undergo the same sequence of pressure-induced phase transitions. • The phase transition pressures correlate with the average size of the A-site cation. • All transitions were reversible with hysteresis. • Previously studied Ga 2 Mo 3 O 12 undergoes the same sequence of transitions.

  13. Acute Exercise and Oxidative Stress: CrossFit™ vs. Treadmill Bout

    Science.gov (United States)

    Kliszczewicz, Brian; Quindry, C. John; Blessing, L. Daniel; Oliver, D. Gretchen; Esco, R. Michael; Taylor, J. Kyle

    2015-01-01

    CrossFit™, a popular high-intensity training modality, has been the subject of scrutiny, with concerns of elevated risk of injury and health. Despite these concerns empirical evidence regarding physiologic stresses including acute oxidative stress is lacking. Therefore, the purpose of this investigation was to examine the acute redox response to a CrossFit™ bout. Furthermore, these findings were compared to a high-intensity treadmill bout as a point of reference. Ten males 26.4 ± 2.7 yrs having three or more months of CrossFit™ experience participated in the present study. Blood plasma was collected at four time points: Pre-exercise (PRE), immediately-post-exercise (IPE), 1 hr-post (1-HP) and 2 hr-post (2-HP), to examine oxidative damage and antioxidant capacity. Regarding plasma oxidative damage, CrossFit™ and Treadmill elicited a time-dependent increase of lipid peroxides 1-HP (CrossFit™=+143%, Treadmill=+115%) and 2-HP (CrossFit™=+256%, Treadmill+167%). Protein Carbonyls were increased IPE in CF only (+5%), while a time-dependent decrease occurred 1-HP (CrossFit™=−16%, Treadmill=−8%) and 2-HP (CF=−16%, TM=−1%) compared to IPE. Regarding antioxidant capacity, Ferric Reducing Antioxidant Power also demonstrated a time-dependent increase within CrossFit™ and Treadmill: IPE (CrossFit™=+25%, Treadmill=+17%), 1-HP (CrossFit™=+26%, Treadmill=+4.8%), 2-HP (CrossFit™=+20%, Treadmill=+12%). Total Enzymatic Antioxidant Capacity showed a time-dependent decrease in IPE (CrossFit™=−10%, Treadmill=−12%), 1-HP (CrossFit™=−12%, Treadmill=−6%), 2-HP (CrossFit™=−7%, Treadmill=−11%). No trial-dependent differences were observed in any biomarker of oxidative stress. The CrossFit™ bout elicited an acute blood oxidative stress response comparable to a traditional bout of high-intensity treadmill running. Results also confirm that exercise intensity and the time course of exercise recovery influence oxidative responses. PMID:26557192

  14. Acute Exercise and Oxidative Stress: CrossFit(™) vs. Treadmill Bout.

    Science.gov (United States)

    Kliszczewicz, Brian; Quindry, C John; Blessing, L Daniel; Oliver, D Gretchen; Esco, R Michael; Taylor, J Kyle

    2015-09-29

    CrossFit(™), a popular high-intensity training modality, has been the subject of scrutiny, with concerns of elevated risk of injury and health. Despite these concerns empirical evidence regarding physiologic stresses including acute oxidative stress is lacking. Therefore, the purpose of this investigation was to examine the acute redox response to a CrossFit(™) bout. Furthermore, these findings were compared to a high-intensity treadmill bout as a point of reference. Ten males 26.4 ± 2.7 yrs having three or more months of CrossFit(™) experience participated in the present study. Blood plasma was collected at four time points: Pre-exercise (PRE), immediately-post-exercise (IPE), 1 hr-post (1-HP) and 2 hr-post (2-HP), to examine oxidative damage and antioxidant capacity. Regarding plasma oxidative damage, CrossFit(™) and Treadmill elicited a time-dependent increase of lipid peroxides 1-HP (CrossFit(™)=+143%, Treadmill=+115%) and 2-HP (CrossFit(™)=+256%, Treadmill+167%). Protein Carbonyls were increased IPE in CF only (+5%), while a time-dependent decrease occurred 1-HP (CrossFit(™)=-16%, Treadmill=-8%) and 2-HP (CF=-16%, TM=-1%) compared to IPE. Regarding antioxidant capacity, Ferric Reducing Antioxidant Power also demonstrated a time-dependent increase within CrossFit(™) and Treadmill: IPE (CrossFit(™)=+25%, Treadmill=+17%), 1-HP (CrossFit(™)=+26%, Treadmill=+4.8%), 2-HP (CrossFit(™)=+20%, Treadmill=+12%). Total Enzymatic Antioxidant Capacity showed a time-dependent decrease in IPE (CrossFit(™)=-10%, Treadmill=-12%), 1-HP (CrossFit(™)=-12%, Treadmill=-6%), 2-HP (CrossFit(™)=-7%, Treadmill=-11%). No trial-dependent differences were observed in any biomarker of oxidative stress. The CrossFit(™) bout elicited an acute blood oxidative stress response comparable to a traditional bout of high-intensity treadmill running. Results also confirm that exercise intensity and the time course of exercise recovery influence oxidative responses.

  15. Acute Exercise and Oxidative Stress: CrossFit™ vs. Treadmill Bout

    Directory of Open Access Journals (Sweden)

    Kliszczewicz Brian

    2015-09-01

    Full Text Available CrossFit™, a popular high-intensity training modality, has been the subject of scrutiny, with concerns of elevated risk of injury and health. Despite these concerns empirical evidence regarding physiologic stresses including acute oxidative stress is lacking. Therefore, the purpose of this investigation was to examine the acute redox response to a CrossFit™ bout. Furthermore, these findings were compared to a high-intensity treadmill bout as a point of reference. Ten males 26.4 ± 2.7 yrs having three or more months of CrossFit™ experience participated in the present study. Blood plasma was collected at four time points: Pre-exercise (PRE, immediately-post-exercise (IPE, 1 hr-post (1-HP and 2 hr-post (2-HP, to examine oxidative damage and antioxidant capacity. Regarding plasma oxidative damage, CrossFit™ and Treadmill elicited a time-dependent increase of lipid peroxides 1-HP (CrossFit™=+143%,Treadmill=+115% and 2-HP (CrossFit™=+256%,Treadmill+167%. Protein Carbonyls were increased IPE in CF only (+5%, while a time-dependent decrease occurred 1-HP (CrossFit™=−16%,Treadmill=−8% and 2-HP (CF=−16%,TM=−1% compared to IPE. Regarding antioxidant capacity, Ferric Reducing Antioxidant Power also demonstrated a time-dependent increase within CrossFit™ and Treadmill: IPE (CrossFit™=+25%,Treadmill=+17%, 1-HP (CrossFit™=+26%,Treadmill=+4.8%, 2-HP (CrossFit™=+20%,Treadmill=+12%. Total Enzymatic Antioxidant Capacity showed a time-dependent decrease in IPE (CrossFit™= −10%,Treadmill=−12%, 1-HP (CrossFit™= −12%,Treadmill=−6%, 2-HP (CrossFit™= −7%,Treadmill=−11%. No trial-dependent differences were observed in any biomarker of oxidative stress. The CrossFit™ bout elicited an acute blood oxidative stress response comparable to a traditional bout of high-intensity treadmill running. Results also confirm that exercise intensity and the time course of exercise recovery influence oxidative responses.

  16. Comparison of standardbred trotters exercising on a treadmill and a race track with identical draught resistances.

    Science.gov (United States)

    Gottlieb-Vedi, M; Lindholm, A

    1997-05-17

    The responses in heart rate, plasma lactate and rectal temperature of standardbred trotters to draught loaded interval exercise on a treadmill and a race track were studied. The horses were exercised with incrementally increasing trotting speeds for two-minute intervals with draught loads of 10, 20 and 30 kilopond (kp) in three different tests. Each trotting interval was followed by two-minute periods at a walk without a draught load. Measurements of heart rate and plasma lactate were made at the end of each interval and the rectal temperature was taken at the end of the exercise. The heart rate and plasma lactate levels were significantly lower on the treadmill than on the track in the tests with 10 kp, but no significant differences were found between the treadmill and track exercise tests with the heavier draught resistances. No differences were observed in rectal temperature between treadmill and track conditions. From these findings it was concluded that the workload was significantly greater on the race track compared to the treadmill when the draught resistance was low (10 kp). Although the workload increased on both the race track and the treadmill as draught resistance increased, at the heavier draught resistances track exercise was no longer more demanding than exercise on the treadmill.

  17. Complexity, fractal dynamics and determinism in treadmill ambulation: Implications for clinical biomechanists.

    Science.gov (United States)

    Hollman, John H; Watkins, Molly K; Imhoff, Angela C; Braun, Carly E; Akervik, Kristen A; Ness, Debra K

    2016-08-01

    Reduced inter-stride complexity during ambulation may represent a pathologic state. Evidence is emerging that treadmill training for rehabilitative purposes may constrain the locomotor system and alter gait dynamics in a way that mimics pathological states. The purpose of this study was to examine the dynamical system components of gait complexity, fractal dynamics and determinism during treadmill ambulation. Twenty healthy participants aged 23.8 (1.2) years walked at preferred walking speeds for 6min on a motorized treadmill and overground while wearing APDM 6 Opal inertial monitors. Stride times, stride lengths and peak sagittal plane trunk velocities were measured. Mean values and estimates of complexity, fractal dynamics and determinism were calculated for each parameter. Data were compared between overground and treadmill walking conditions. Mean values for each gait parameter were statistically equivalent between overground and treadmill ambulation (P>0.05). Through nonlinear analyses, however, we found that complexity in stride time signals (P<0.001), and long-range correlations in stride time and stride length signals (P=0.005 and P=0.024, respectively), were reduced on the treadmill. Treadmill ambulation induces more predictable inter-stride time dynamics and constrains fluctuations in stride times and stride lengths, which may alter feedback from destabilizing perturbations normally experienced by the locomotor control system during overground ambulation. Treadmill ambulation, therefore, may provide less opportunity for experiencing the adaptability necessary to successfully ambulate overground. Investigators and clinicians should be aware that treadmill ambulation will alter dynamic gait characteristics. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Counteracting negative venous line pressures to avoid arterial air bubbles: an experimental study comparing two different types of miniaturized extracorporeal perfusion systems.

    Science.gov (United States)

    Aboud, Anas; Mederos-Dahms, Hendrikje; Liebing, Kai; Zittermann, Armin; Schubert, Harald; Murray, Edward; Renner, Andre; Gummert, Jan; Börgermann, Jochen

    2015-05-29

    Because of its low rate of clinical complications, miniaturized extracorporeal perfusion systems (MEPS) are frequently used in heart centers worldwide. However, many recent studies refer to the higher probability of gaseous microemboli formation by MEPS, caused by subzero pressure values. This is the main reason why various de-airing devices were developed for today's perfusion systems. In the present study, we investigated the potential benefits of a simple one-way-valve connected to a volume replacement reservoir (OVR) for volume and pressure compensation. In an experimental study on 26 pigs, we compared MEPS (n = 13) with MEPS plus OVR (n = 13). Except OVR, perfusion equipment was identical in both groups. Primary endpoints were pressure values in the venous line and the right atrium as well as the number and volume of air bubbles. Secondary endpoints were biochemical parameters of systemic inflammatory response, ischemia, hemodilution and hemolysis. One animal was lost in the MEPS + OVR group. In the MEPS + OVR group no pressure values below -150 mmHg in the venous line and no values under -100 mmHg in right atrium were noticed. On the contrary, nearly 20% of venous pressure values in the MEPS group were below -150 and approximately 10% of right atrial pressure values were below -100 mmHg. Compared with the MEPS group, the bubble counter device showed lower numbers of arterial air bubbles in the MEPS + OVR group (mean ± SD: 13444 ± 5709 vs. 1 ± 2, respectively; p pressures and to reduce the number and volume of arterial air bubbles. This approach may lead to a lower rate of neurological complications.

  19. Structures of Bordered Pits Potentially Contributing to Isolation of a Refilled Vessel from Negative Xylem Pressure in Stems of Morus australis Poir.: Testing of the Pit Membrane Osmosis and Pit Valve Hypotheses.

    Science.gov (United States)

    Ooeda, Hiroki; Terashima, Ichiro; Taneda, Haruhiko

    2017-02-01

    Two hypotheses have been proposed to explain the mechanism preventing the refilling vessel water from being drained to the neighboring functional vessels under negative pressure. The pit membrane osmosis hypothesis proposes that the xylem parenchyma cells release polysaccharides that are impermeable to the intervessel pit membranes into the refilling vessel; this osmotically counteracts the negative pressure, thereby allowing the vessel to refill. The pit valve hypothesis proposes that gas trapped within intervessel bordered pits isolates the refilling vessel water from the surrounding functional vessels. Here, using the single-vessel method, we assessed these hypotheses in shoots of mulberry (Morus australis Poir.). First, we confirmed the occurrence of xylem refilling under negative pressure in the potted mulberry saplings. To examine the pit membrane osmosis hypothesis, we estimated the semi-permeability of pit membranes for molecules of various sizes and found that the pit membranes were not semi-permeable to polyethylene glycol of molecular mass osmosis mechanism in mulberry would be unrealistically large. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  20. Inactivation of Gram-Negative Bacteria by Low-Pressure RF Remote Plasma Excited in N2-O2 Mixture and SF6 Gases

    Directory of Open Access Journals (Sweden)

    Ayman Al-Mariri

    2013-12-01

    Full Text Available The role of low-pressure RF plasma in the inactivation of Escherichia coli O157, Klebsiella pneumoniae, Proteus mirabilis, and Enterobacter sakazakii using N2-O2 and SF6 gases was assessed. 1×109 colony-forming units (CFUs of each bacterial isolate were placed on three polymer foils. The effects of pressure, power, distance from the source, and exposure time to plasma gases were optimized. The best conditions to inactivate the four bacteria were a 91%N2-9%O2 mixture and a 30-minute exposure time. SF6 gas was more efficient for all the tested isolates in as much as the treatment time was reduced to only three minutes. Therefore, low-pressure plasma could be used to sterilize heat and/or moisture-sensitive medical instruments.

  1. Plasma homocysteine level in cardiac syndrome X and its relation with duke treadmill score

    International Nuclear Information System (INIS)

    Timurkaynak, T.; Balcioglu, S.; Arslan, U.; Kocaman, Sinan A.; Cengel, A.

    2008-01-01

    Objective was to investigate the plasma homocysteine level and relationship between plasma homocysteine level and duke treadmill score (DTS) in cardiac syndrome X (CSX) patients. Seventy-nine patients (36 male, 43 female, mean age: 50+-8.8 years) admitted to Gazi University Hospital, Ankara, Turkey with typical effort angina, positive stress test and angiographically normal coronary arteries between January and September 2006 were included in this prospective and controlled study. Thirty asymptomatic patients (11 male, 19 female, mean age: 47.6+-8.3 years) with two cardiovascular risk factors were chosen as a control group. Plasma homocysteine level was measured in both groups and DTS was calculated in the CSX group. Plasma homocysteine was measured with AxSYM homocysteine immunoassay method in both groups. Plasma homocysteine level was higher in the CSx group compared to the control group 16.5+-4.9 umol/L, n=79, versus 12.4+-4.1 umol/L, n=30, p<0.001). The DTS was -2.7+-5.3 in the CSX group. There was a negative correlation between the DTS and homocysteine levels in the CSX group. (r=-0.506, p<0.001). Plasma homocysteine level, which is known to cause endothelial dysfunction and microvascular ischemia were higher in CSX patients. Also, this increase in homocysteine level correlated with the DTS, which represents the magnitude of ischemia. (author)

  2. Body-weight-supported treadmill rehabilitation after stroke.

    Science.gov (United States)

    Duncan, Pamela W; Sullivan, Katherine J; Behrman, Andrea L; Azen, Stanley P; Wu, Samuel S; Nadeau, Stephen E; Dobkin, Bruce H; Rose, Dorian K; Tilson, Julie K; Cen, Steven; Hayden, Sarah K

    2011-05-26

    Locomotor training, including the use of body-weight support in treadmill stepping, is a physical therapy intervention used to improve recovery of the ability to walk after stroke. The effectiveness and appropriate timing of this intervention have not been established. We stratified 408 participants who had had a stroke 2 months earlier according to the extent of walking impairment--moderate (able to walk 0.4 to stroke had occurred (early locomotor training), the second group received this training 6 months after the stroke had occurred (late locomotor training), and the third group participated in an exercise program at home managed by a physical therapist 2 months after the stroke (home-exercise program). Each intervention included 36 sessions of 90 minutes each for 12 to 16 weeks. The primary outcome was the proportion of participants in each group who had an improvement in functional walking ability 1 year after the stroke. At 1 year, 52.0% of all participants had increased functional walking ability. No significant differences in improvement were found between early locomotor training and home exercise (adjusted odds ratio for the primary outcome, 0.83; 95% confidence interval [CI], 0.50 to 1.39) or between late locomotor training and home exercise (adjusted odds ratio, 1.19; 95% CI, 0.72 to 1.99). All groups had similar improvements in walking speed, motor recovery, balance, functional status, and quality of life. Neither the delay in initiating the late locomotor training nor the severity of the initial impairment affected the outcome at 1 year. Ten related serious adverse events were reported (occurring in 2.2% of participants undergoing early locomotor training, 3.5% of those undergoing late locomotor training, and 1.6% of those engaging in home exercise). As compared with the home-exercise group, each of the groups receiving locomotor training had a higher frequency of dizziness or faintness during treatment (P=0.008). Among patients with severe walking

  3. Treadmill vs. overground walking: different response to physical interaction.

    Science.gov (United States)

    Ochoa, Julieth; Sternad, Dagmar; Hogan, Neville

    2017-10-01

    Rehabilitation of human motor function is an issue of growing significance, and human-interactive robots offer promising potential to meet the need. For the lower extremity, however, robot-aided therapy has proven challenging. To inform effective approaches to robotic gait therapy, it is important to better understand unimpaired locomotor control: its sensitivity to different mechanical contexts and its response to perturbations. The present study evaluated the behavior of 14 healthy subjects who walked on a motorized treadmill and overground while wearing an exoskeletal ankle robot. Their response to a periodic series of ankle plantar flexion torque pulses, delivered at periods different from, but sufficiently close to, their preferred stride cadence, was assessed to determine whether gait entrainment occurred, how it differed across conditions, and if the adapted motor behavior persisted after perturbation. Certain aspects of locomotor control were exquisitely sensitive to walking context, while others were not. Gaits entrained more often and more rapidly during overground walking, yet, in all cases, entrained gaits synchronized the torque pulses with ankle push-off, where they provided assistance with propulsion. Furthermore, subjects entrained to perturbation periods that required an adaption toward slower cadence, even though the pulses acted to accelerate gait, indicating a neural adaptation of locomotor control. Lastly, during 15 post-perturbation strides, the entrained gait period was observed to persist more frequently during overground walking. This persistence was correlated with the number of strides walked at the entrained gait period (i.e., longer exposure), which also indicated a neural adaptation. NEW & NOTEWORTHY We show that the response of human locomotion to physical interaction differs between treadmill and overground walking. Subjects entrained to a periodic series of ankle plantar flexion torque pulses that shifted their gait cadence

  4. Investigation of the effect of mechanical pressure on the performance of negative lead accumulator electrodes during partial state of charge operation

    Czech Academy of Sciences Publication Activity Database

    Bača, P.; Micka, Karel; Křivík, P.; Tonar, K.; Tošer, P.

    2012-01-01

    Roč. 207, JUN 1 2012 (2012), s. 37-44 ISSN 0378-7753 Institutional research plan: CEZ:AV0Z40400503 Keywords : Lead battery electrodes * Doping with carbon or titanium dioxide * Effect of mechanical pressure Subject RIV: CG - Electrochemistry Impact factor: 4.675, year: 2012

  5. When negation is not negation

    OpenAIRE

    Milicevic, Nataša

    2008-01-01

    In this paper I will discuss the formation of different types of yes/no questions in Serbian (examples in (1)), focusing on the syntactically and semantically puzzling example (1d), which involves the negative auxiliary inversion. Although there is a negative marker on the fronted auxiliary, the construction does not involve sentential negation. This coincides with the fact that the negative quantifying NPIs cannot be licensed. The question formation and sentential negation have similar synta...

  6. Psychophysical and ergogenic effects of synchronous music during treadmill walking.

    Science.gov (United States)

    Karageorghis, Costas I; Mouzourides, Denis A; Priest, David-Lee; Sasso, Tariq A; Morrish, Daley J; Walley, Carolyn J

    2009-02-01

    The present study examined the impact of motivational music and oudeterous (neutral in terms of motivational qualities) music on endurance and a range of psychophysical indices during a treadmill walking task. Experimental participants (N=30; mean age=20.5 years, SD=1.0 years) selected a program of either pop or rock tracks from artists identified in an earlier survey. They walked to exhaustion, starting at 75% maximal heart rate reserve, under conditions of motivational synchronous music, oudeterous synchronous music, and a no-music control. Dependent measures included time to exhaustion, ratings of perceived exertion (RPE), and in-task affect (both recorded at 2-min intervals), and exercise-induced feeling states. A one-way repeated measures ANOVA was used to analyze time to exhaustion data. Two-way repeated measures (Music Condition ? Trial Point) ANOVAs were used to analyze in-task measures, whereas a one-way repeated measures MANOVA was used to analyze the exercise-induced feeling states data. Results indicated that endurance was increased in both music conditions and that motivational music had a greater ergogenic effect than did oudeterous music (pmusic when compared with control throughout the trial (p.05) upon RPE or exercise-induced feeling states, although a moderate effect size was recorded for the latter (etap2=.09). The present results indicate that motivational synchronous music can elicit an ergogenic effect and enhance in-task affect during an exhaustive endurance task.

  7. Improved kinect-based spatiotemporal and kinematic treadmill gait assessment.

    Science.gov (United States)

    Eltoukhy, Moataz; Oh, Jeonghoon; Kuenze, Christopher; Signorile, Joseph

    2017-01-01

    A cost-effective, clinician friendly gait assessment tool that can automatically track patients' anatomical landmarks can provide practitioners with important information that is useful in prescribing rehabilitative and preventive therapies. This study investigated the validity and reliability of the Microsoft Kinect v2 as a potential inexpensive gait analysis tool. Ten healthy subjects walked on a treadmill at 1.3 and 1.6m·s -1 , as spatiotemporal parameters and kinematics were extracted concurrently using the Kinect and three-dimensional motion analysis. Spatiotemporal measures included step length and width, step and stride times, vertical and mediolateral pelvis motion, and foot swing velocity. Kinematic outcomes included hip, knee, and ankle joint angles in the sagittal plane. The absolute agreement and relative consistency between the two systems were assessed using interclass correlations coefficients (ICC2,1), while reproducibility between systems was established using Lin's Concordance Correlation Coefficient (rc). Comparison of ensemble curves and associated 90% confidence intervals (CI90) of the hip, knee, and ankle joint angles were performed to investigate if the Kinect sensor could consistently and accurately assess lower extremity joint motion throughout the gait cycle. Results showed that the Kinect v2 sensor has the potential to be an effective clinical assessment tool for sagittal plane knee and hip joint kinematics, as well as some spatiotemporal temporal variables including pelvis displacement and step characteristics during the gait cycle. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Thermoregulatory responses to skin wetting during prolonged treadmill running.

    Science.gov (United States)

    Bassett, D R; Nagle, F J; Mookerjee, S; Darr, K C; Ng, A V; Voss, S G; Napp, J P

    1987-02-01

    We examined the physiological responses to skin wetting during a 120-min level treadmill run to assess whether skin wetting would reduce the dehydration and the increase in core temperature associated with prolonged exercise. Testing was conducted in an environmental chamber (T = 29.5 degrees C, wind velocity = 3 m X sec-1) under two different humidity conditions (33 or 66% relative humidity). Ten male subjects performed two runs in each humidity condition; one served as a control run. The other included spraying the body with 50 ml of water (T = 29.5 degrees C) every 10 min. Spraying had no effect on rectal temperature (Tre), heart rate, oxygen consumption, perceived exertion, sweat loss, or percent change in plasma volume in both the humid and the dry conditions. Spraying produced a significant reduction in mean skin temperature (Tsk), which increased the (Tre - Tsk) gradient. At the same time, overall skin conductance (K) was decreased, presumably as a result of cutaneous vasoconstriction due to the low Tsk. Since heat transfer from the body's core to the skin is expressed by the equation: heat transfer = K X (Tre - Tsk) the spraying had no effect on heat transfer away from the core, and Tre remained unchanged.

  9. Multi-segment foot kinematics and plantar fascia strain during treadmill and overground running

    OpenAIRE

    Sinclair, Jonathan Kenneth; Taylor, Paul John; Vincent, Hayley

    2014-01-01

    Although physiologically beneficial, running is known to be associated with a high incidence of chronic injuries. Excessive coronal and transverse plane motions of the foot segments and strain experienced by the plantar fascia are linked to the development of a number of chronic injuries. This study examined differences in multi-segment foot kinematics and plantar fascia strain during treadmill and overground running. Twelve male recreational runners ran at 4.0 m.s-1 in both treadmill and ove...

  10. Design of a heart rate controller for treadmill exercise using a recurrent fuzzy neural network.

    Science.gov (United States)

    Lu, Chun-Hao; Wang, Wei-Cheng; Tai, Cheng-Chi; Chen, Tien-Chi

    2016-05-01

    In this study, we developed a computer controlled treadmill system using a recurrent fuzzy neural network heart rate controller (RFNNHRC). Treadmill speeds and inclines were controlled by corresponding control servo motors. The RFNNHRC was used to generate the control signals to automatically control treadmill speed and incline to minimize the user heart rate deviations from a preset profile. The RFNNHRC combines a fuzzy reasoning capability to accommodate uncertain information and an artificial recurrent neural network learning process that corrects for treadmill system nonlinearities and uncertainties. Treadmill speeds and inclines are controlled by the RFNNHRC to achieve minimal heart rate deviation from a pre-set profile using adjustable parameters and an on-line learning algorithm that provides robust performance against parameter variations. The on-line learning algorithm of RFNNHRC was developed and implemented using a dsPIC 30F4011 DSP. Application of the proposed control scheme to heart rate responses of runners resulted in smaller fluctuations than those produced by using proportional integra control, and treadmill speeds and inclines were smoother. The present experiments demonstrate improved heart rate tracking performance with the proposed control scheme. The RFNNHRC scheme with adjustable parameters and an on-line learning algorithm was applied to a computer controlled treadmill system with heart rate control during treadmill exercise. Novel RFNNHRC structure and controller stability analyses were introduced. The RFNNHRC were tuned using a Lyapunov function to ensure system stability. The superior heart rate control with the proposed RFNNHRC scheme was demonstrated with various pre-set heart rates. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  11. Implications of treadmilling for the stability and polarity of actin and tubulin polymers in vivo.

    Science.gov (United States)

    Kirschner, M W

    1980-07-01

    In this report, we examine how the cell can selectively stabilize anchored filaments and suppress spontaneous filament assembly. Because microtubules and actin filaments have an organized distribution in cells, the cell must have a mechanism for suppressing spontaneous and random polymerization. Though the mechanism for suppressing spontaneous polymerization is unknown, an unusual property of these filaments has been demonstrated recently, i.e., under steady-stae conditions, in vitro actin filaments and microtubules can exhibit a flux of subunits through the polymers called "treadmilling." In vivo, however, most, if not all, of these polymers are attached at one end to specific structures and treadmilling should not occur. The function of treadmilling in vivo is, therefore, unclear at present. However, as shown here, the same physicochemical property of coupling assembly to ATP or GTP hydrolysis that leads to treadmilling in vitro can act to selectively stabilize anchored polymers in vivo. I show here that the theory of treadmilling implies that the concentration of subunits necessary for assembly of the nonanchored polymer will in general be higher than the concentration necessary for the assembly of polymers anchored with a specific polarity. This disparity in the monomer concentrations required for assembly can lead to a selective stabilization of anchored polymers and complete suppression of spontaneous polymerization at apparent equilibrium in vivo. It is possible, therefore, that the phenomenon of treadmilling is an in vitro manifestation of a mechanism designed to use ATP or GTP hydrolysis to control the spatial organization of filaments in the cell.

  12. A systematic review of standing and treadmill desks in the workplace.

    Science.gov (United States)

    MacEwen, Brittany T; MacDonald, Dany J; Burr, Jamie F

    2015-01-01

    Standing and treadmill desks are intended to reduce the amount of time spent sitting in today's otherwise sedentary office. Proponents of these desks suggest that health benefits may be acquired as standing desk use discourages long periods of sitting, which has been identified as an independent health risk factor. Our objectives were thus to analyze the evidence for standing and treadmill desk use in relation to physiological (chronic disease prevention and management) and psychological (worker productivity, well-being) outcomes. A computer-assisted systematic search of Medline, PubMed, PsycINFO, SPORTDiscus, CINAHL, CENTRAL, and EMBASE databases was employed to identify all relevant articles related to standing and treadmill desk use. Treadmill desks led to the greatest improvement in physiological outcomes including postprandial glucose, HDL cholesterol, and anthropometrics, while standing desk use was associated with few physiological changes. Standing and treadmill desks both showed mixed results for improving psychological well-being with little impact on work performance. Standing and treadmill desks show some utility for breaking up sitting time and potentially improving select components of health. At present; however, there exist substantial evidence gaps to comprehensively evaluate the utility of each type of desk to enhance health benefits by reducing sedentary time. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Fall-related gait characteristics on the treadmill and in daily life.

    Science.gov (United States)

    Rispens, Sietse M; Van Dieën, Jaap H; Van Schooten, Kimberley S; Cofré Lizama, L Eduardo; Daffertshofer, Andreas; Beek, Peter J; Pijnappels, Mirjam

    2016-02-02

    Body-worn sensors allow assessment of gait characteristics that are predictive of fall risk, both when measured during treadmill walking and in daily life. The present study aimed to assess differences as well as associations between fall-related gait characteristics measured on a treadmill and in daily life. In a cross-sectional study, trunk accelerations of 18 older adults (72.3 ± 4.5 years) were recorded during walking on a treadmill (Dynaport Hybrid sensor) and during daily life (Dynaport MoveMonitor). A comprehensive set of 32 fall-risk-related gait characteristics was estimated and compared between both settings. For 25 gait characteristics, a systematic difference between treadmill and daily-life measurements was found. Gait was more variable, less symmetric, and less stable during daily life. Fourteen characteristics showed a significant correlation between treadmill and daily-life measurements, including stride time and regularity (0.48  0.25). Gait characteristics revealed less stable, less symmetric, and more variable gait during daily life than on a treadmill, yet about half of the characteristics were significantly correlated between conditions. These results suggest that daily-life gait analysis is sensitive to static personal factors (i.e., physical and cognitive capacity) as well as dynamic situational factors (i.e., behavior and environment), which may both represent determinants of fall risk.

  14. A new low-cost negative-pressure wound therapy versus a commercially available therapy device widely used to treat complex traumatic injuries: a prospective, randomized, non-inferiority trial

    Directory of Open Access Journals (Sweden)

    Fabio Kamamoto

    Full Text Available OBJECTIVES: Negative-pressure wound therapy has been widely adopted to reduce the complexity of treating a broad range of acute and chronic wounds. However, its cost is high. The objective of this study was to evaluate the following two different methods of negative-pressure wound therapy in terms of healing time: a low-cost method of negative-pressure wound therapy (a pressure stabilizer device connected to a hospital wall-vacuum system with a gauze-sealed dressing, USP and the standard of care (vacuum-assisted closure, VAC. METHODS: This is a randomized, controlled, non-inferiority, unblinded trial. Patients admitted with complex injuries to a trauma center in a public referral hospital who were indicated for orthopedic surgery were randomized to a USP or VAC group. The primary outcome was the time required to achieve a “ready for surgery condition”, which was defined as a wound bed with healthy granulation tissue and without necrosis or purulent secretion. Wound bed area contraction, granulation tissue growth and the direct costs of the dressings were secondary outcomes. RESULTS: Variation in area and granulation tissue growth were essentially the same between the systems, and healing time was equal between the groups (p=0.379. In both systems, serial debridement increased wound area (p=0.934, and granulation tissue was also increased (p=0.408. The mean treatment cost was US$ 15.15 in the USP group and US$ 872.59 in the VAC group. CONCLUSIONS: For treating complex traumatic injuries, USP was non-inferior to and less expensive than VAC.

  15. A new low-cost negative-pressure wound therapy versus a commercially available therapy device widely used to treat complex traumatic injuries: a prospective, randomized, non-inferiority trial.

    Science.gov (United States)

    Kamamoto, Fabio; Lima, Ana Lucia Munhoz; Rezende, Marcelo Rosa de; Mattar-Junior, Rames; Leonhardt, Marcos de Camargo; Kojima, Kodi Edson; Santos, Carla Chineze Dos

    2017-12-01

    Negative-pressure wound therapy has been widely adopted to reduce the complexity of treating a broad range of acute and chronic wounds. However, its cost is high. The objective of this study was to evaluate the following two different methods of negative-pressure wound therapy in terms of healing time: a low-cost method of negative-pressure wound therapy (a pressure stabilizer device connected to a hospital wall-vacuum system with a gauze-sealed dressing, USP) and the standard of care (vacuum-assisted closure, VAC). This is a randomized, controlled, non-inferiority, unblinded trial. Patients admitted with complex injuries to a trauma center in a public referral hospital who were indicated for orthopedic surgery were randomized to a USP or VAC group. The primary outcome was the time required to achieve a "ready for surgery condition", which was defined as a wound bed with healthy granulation tissue and without necrosis or purulent secretion. Wound bed area contraction, granulation tissue growth and the direct costs of the dressings were secondary outcomes. Variation in area and granulation tissue growth were essentially the same between the systems, and healing time was equal between the groups (p=0.379). In both systems, serial debridement increased wound area (p=0.934), and granulation tissue was also increased (p=0.408). The mean treatment cost was US$ 15.15 in the USP group and US$ 872.59 in the VAC group. For treating complex traumatic injuries, USP was non-inferior to and less expensive than VAC.

  16. High negative pressure subcutaneous suction drain for managing debilitating subcutaneous emphysema secondary to tube thoracostomy for an iatrogenic post computed tomography guided transthoracic needle biopsy pneumothorax: Case report and review of literature.

    Science.gov (United States)

    Ahmed, Zeeshan; Patel, Pinakin; Singh, Suresh; Sharma, Raj Govind; Somani, Pankaj; Gouri, Abdul Rauf; Singh, Shiv

    2016-01-01

    Subcutaneous emphysema is a common complication of tube thoracostomy. Though self-limiting, it should be treated when it causes palpebral closure, dyspnea, dysphagia or undue disfigurement resulting in anxiety and distress to the patient. A 72year old man who was a known case of COPD on bronchodilators developed a large pneumothorax and respiratory distress after a CT guided transthoracic lung biopsy done for a lung opacity (approx. 3×3cm) at the right hilar region on Chest X-ray. Within 24h of an urgent tube thoracostomy, patient developed intractable subcutaneous emphysema with closure of palpebral fissure and dyspnea unresponsive to increasing suction on chest tube. A subcutaneous fenestrated drain was placed mid-way between the nipple and clavicle in the mid-clavicular line bilaterally. Continuous negative suction (-150mmHg) resulted in immediate, sustained relief and complete resolution within 5days. Extensive and debilitating SE (subcutaneous emphysema) has to be treated promptly to relieve patient discomfort, dysphagia or imminent respiratory compromise. A variety of treatment have been tried including infraclavicular blow-hole incisions, subcutaneous drains +/- negative pressure suction, fenestrated angiocatheters, Vacuum assisted dressings and increasing suction on a pre-existing chest tube. We describe a high negative pressure subcutaneous suction drain which provides immediate and sustained relief in debilitating SE. Debilitating subcutaneous emphysema which causes distress, anxiety, palpebral closure, dyspnoea or dysphagia requires intervention. High negative pressure subcutaneous suction drain provides immediate and sustained relief in extensive and debilitating SE. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  17. Human-Robot Interaction: Does Robotic Guidance Force Affect Gait-Related Brain Dynamics during Robot-Assisted Treadmill Walking?

    Directory of Open Access Journals (Sweden)

    Kristel Knaepen

    Full Text Available In order to determine optimal training parameters for robot-assisted treadmill walking, it is essential to understand how a robotic device interacts with its wearer, and thus, how parameter settings of the device affect locomotor control. The aim of this study was to assess the effect of different levels of guidance force during robot-assisted treadmill walking on cortical activity. Eighteen healthy subjects walked at 2 km.h-1 on a treadmill with and without assistance of the Lokomat robotic gait orthosis. Event-related spectral perturbations and changes in power spectral density were investigated during unassisted treadmill walking as well as during robot-assisted treadmill walking at 30%, 60% and 100% guidance force (with 0% body weight support. Clustering of independent components revealed three clusters of activity in the sensorimotor cortex during treadmill walking and robot-assisted treadmill walking in healthy subjects. These clusters demonstrated gait-related spectral modulations in the mu, beta and low gamma bands over the sensorimotor cortex related to specific phases of the gait cycle. Moreover, mu and beta rhythms were suppressed in the right primary sensory cortex during treadmill walking compared to robot-assisted treadmill walking with 100% guidance force, indicating significantly larger involvement of the sensorimotor area during treadmill walking compared to robot-assisted treadmill walking. Only marginal differences in the spectral power of the mu, beta and low gamma bands could be identified between robot-assisted treadmill walking with different levels of guidance force. From these results it can be concluded that a high level of guidance force (i.e., 100% guidance force and thus a less active participation during locomotion should be avoided during robot-assisted treadmill walking. This will optimize the involvement of the sensorimotor cortex which is known to be crucial for motor learning.

  18. Human-Robot Interaction: Does Robotic Guidance Force Affect Gait-Related Brain Dynamics during Robot-Assisted Treadmill Walking?

    Science.gov (United States)

    Knaepen, Kristel; Mierau, Andreas; Swinnen, Eva; Fernandez Tellez, Helio; Michielsen, Marc; Kerckhofs, Eric; Lefeber, Dirk; Meeusen, Romain

    2015-01-01

    In order to determine optimal training parameters for robot-assisted treadmill walking, it is essential to understand how a robotic device interacts with its wearer, and thus, how parameter settings of the device affect locomotor control. The aim of this study was to assess the effect of different levels of guidance force during robot-assisted treadmill walking on cortical activity. Eighteen healthy subjects walked at 2 km.h-1 on a treadmill with and without assistance of the Lokomat robotic gait orthosis. Event-related spectral perturbations and changes in power spectral density were investigated during unassisted treadmill walking as well as during robot-assisted treadmill walking at 30%, 60% and 100% guidance force (with 0% body weight support). Clustering of independent components revealed three clusters of activity in the sensorimotor cortex during treadmill walking and robot-assisted treadmill walking in healthy subjects. These clusters demonstrated gait-related spectral modulations in the mu, beta and low gamma bands over the sensorimotor cortex related to specific phases of the gait cycle. Moreover, mu and beta rhythms were suppressed in the right primary sensory cortex during treadmill walking compared to robot-assisted treadmill walking with 100% guidance force, indicating significantly larger involvement of the sensorimotor area during treadmill walking compared to robot-assisted treadmill walking. Only marginal differences in the spectral power of the mu, beta and low gamma bands could be identified between robot-assisted treadmill walking with different levels of guidance force. From these results it can be concluded that a high level of guidance force (i.e., 100% guidance force) and thus a less active participation during locomotion should be avoided during robot-assisted treadmill walking. This will optimize the involvement of the sensorimotor cortex which is known to be crucial for motor learning.

  19. Results of a retrospective comparative study: material cost for managing a series of large wounds in subjects with serious morbidity with a hydrokinetic fiber dressing or negative pressure wound therapy.

    Science.gov (United States)

    Hermans, Michel H E; Kwon Lee, S; Ragan, Mitzie R; Laudi, Pam

    2015-03-01

    This retrospective observational study analyzed lesions with regard to healing trends and cost of materials. The observed lesions were mostly postsurgical or stage IV pressure ulcers in patients with serious morbidity. The wounds were treated with a hydrokinetic fiber dressing (sorbion Sachet S, sorbion Gmbh & Co, a BSN medical company, Senden, Germany) (n = 26) or negative pressure wound therapy (NPWT) (n = 16). Primary healing trends (ie, reduction of wound size, change from necrosis to granulation tissue, and change from granulation tissue to epithelium) and secondary healing trends (ie, periwound conditions) were similar for wounds treated with the hydrokinetic dressing when compared to wounds treated with NPWT. Cost of materials was substantially lower for wounds treated with the hydrokinetic fiber dressing compared to the NPWT, with cost reductions of $1,640 (348%) to $2,242 (1794%) per wound, depending on the criteria used for the analysis. In this set of wounds, the hydrokinetic fiber dressing was shown to lead to similar healing results while providing substantial reductions of the cost of materials. For the types of wounds presented in this observational study, the hydrokinetic fiber dressing seems to be an effective substitution for negative pressure wound therapy.

  20. Effects of synchronous music on treadmill running among elite triathletes.

    Science.gov (United States)

    Terry, Peter C; Karageorghis, Costas I; Saha, Alessandra Mecozzi; D'Auria, Shaun

    2012-01-01

    Music can provide ergogenic, psychological, and psychophysical benefits during physical activity, especially when movements are performed synchronously with music. The present study developed the train of research on synchronous music and extended it to elite athletes. Repeated-measures laboratory experiment. Elite triathletes (n=11) ran in time to self-selected motivational music, a neutral equivalent and a no-music control during submaximal and exhaustive treadmill running. Measured variables were time-to-exhaustion, mood responses, feeling states, RPE, blood lactate concentration, oxygen consumption and running economy. Time-to-exhaustion was 18.1% and 19.7% longer, respectively, when running in time to motivational and neutral music, compared to no music. Mood responses and feeling states were more positive with motivational music compared to either neutral music or no music. RPE was lowest for neutral music and highest for the no-music control. Blood lactate concentrations were lowest for motivational music. Oxygen consumption was lower with music by 1.0%-.7%. Both music conditions were associated with better running economy than the no-music control. Although neutral music did not produce the same level of psychological benefits as motivational music, it proved equally beneficial in terms of time-to-exhaustion and oxygen consumption. In functional terms, the motivational qualities of music may be less important than the prominence of its beat and the degree to which participants are able to synchronise their movements to its tempo. Music provided ergogenic, psychological and physiological benefits in a laboratory study and its judicious use during triathlon training should be considered. Copyright © 2011 Sports Medicine Australia. All rights reserved.

  1. Negative mass

    International Nuclear Information System (INIS)

    Hammond, Richard T

    2015-01-01

    Some physical aspects of negative mass are examined. Several unusual properties, such as the ability of negative mass to penetrate any armor, are analysed. Other surprising effects include the bizarre system of negative mass chasing positive mass, naked singularities and the violation of cosmic censorship, wormholes, and quantum mechanical results as well. In addition, a brief look into the implications for strings is given. (paper)

  2. Effects of adding a virtual reality environment to different modes of treadmill walking.

    Science.gov (United States)

    Sloot, L H; van der Krogt, M M; Harlaar, J

    2014-03-01

    Differences in gait between overground and treadmill walking are suggested to result from imposed treadmill speed and lack of visual flow. To counteract this effect, feedback-controlled treadmills that allow the subject to control the belt speed along with an immersive virtual reality (VR) have recently been developed. We studied the effect of adding a VR during both fixed speed (FS) and self-paced (SP) treadmill walking. Nineteen subjects walked on a dual-belt instrumented treadmill with a simple endless road projected on a 180° circular screen. A main effect of VR was found for hip flexion offset, peak hip extension, peak knee extension moment, knee flexion moment gain and ankle power during push off. A consistent interaction effect between VR and treadmill mode was found for 12 out of 30 parameters, although the differences were small and did not exceed 50% of the within subject stride variance. At FS, the VR seemed to slightly improve the walking pattern towards overground walking, with for example a 6.5mm increase in stride length. At SP, gait became slightly more cautious by adding a VR, with a 9.1mm decrease in stride length. Irrespective of treadmill mode, subjects rated walking with the VR as more similar to overground walking. In the context of clinical gait analysis, the effects of VR are too small to be relevant and are outweighed by the gains of adding a VR, such as a more stimulating experience and possibility of augmenting it by real-time feedback. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Treatment of chronic heel osteomyelitis in vasculopathic patients. Can the combined use of Integra® , skin graft and negative pressure wound therapy be considered a valid therapeutic approach after partial tangential calcanectomy?

    Science.gov (United States)

    Fraccalvieri, Marco; Pristerà, Giuseppe; Zingarelli, Enrico; Ruka, Erind; Bruschi, Stefano

    2012-04-01

    Osteomyelitis of the calcaneus is a difficult problem to manage. Patients affected by osteomyelitis of the calcaneus often have a below-the-knee amputation because of their comorbidity. In this article, we present seven cases of heel ulcerations with chronic osteomyelitis treated with Integra(®) Dermal Regeneration Template, skin graft and negative pressure wound therapy after partial tangential calcanectomy, discussing the surgical and functional results. In this casuistic of patients, all wounds healed after skin grating of the neodermis generated by Integra(®), with no patient requiring a below-knee amputation. © 2011 The Authors. © 2011 Blackwell Publishing Ltd and Medicalhelplines.com Inc.

  4. The effects of intermittent negative pressure on the lower extremities' peripheral circulation and wound healing in four patients with lower limb ischemia and hard-to-heal leg ulcers: a case report.

    Science.gov (United States)

    Sundby, Øyvind H; Høiseth, Lars Ø; Mathiesen, Iacob; Jørgensen, Jørgen J; Sundhagen, Jon O; Hisdal, Jonny

    2016-10-01

    Peripheral circulation is severely compromised in the advanced stages of peripheral arterial disease. Recently, it was shown that the application of -40 mmHg intermittent negative pressure (INP) to the lower leg and foot enhances macro- and microcirculation in healthy volunteers. In this case report, we describe the effects of INP treatment on four patients with lower limb ischemia and hard-to-heal leg and foot ulcers. We hypothesized that INP therapy may have beneficial hemodynamic and clinical effects in the patients. Four patients (age range: 61-79 years) with hard-to-heal leg and foot ulcers (6-24 months) and ankle-brachial pressure indices of ≤0.60 on the affected side were included. They were treated with an 8-week intervention period of -40 mmHg INP (10 sec negative pressure and 7 sec atmospheric pressure) on the lower limbs. A custom-made vacuum chamber was used to apply INP to the affected lower leg and foot for 2 h per day. After 8 weeks of INP therapy, one ulcer healed completely, while the other three ulcers were almost completely healed. These cases suggest that INP may facilitate wound healing. The theoretical foundation is that INP assists wound healing by improving blood flow to the small blood vessels in the affected limb, increasing the flow of oxygen and nutrients to the cells. © 2016 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

  5. Negative Leadership

    Science.gov (United States)

    2013-03-01

    Negative Leadership by Colonel David M. Oberlander United States Army United States Army War...SUBTITLE Negative Leadership 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Colonel David M...Dr. Richard C. Bullis Department of Command Leadership , and Management 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING

  6. Negative liability

    NARCIS (Netherlands)

    Dari-Mattiacci, G.

    2009-01-01

    Negative and positive externalities pose symmetrical problems to social welfare. The law internalizes negative externalities by providing general tort liability rules. According to such rules, those who cause harm to others should pay compensation. In theory, in the presence of positive

  7. Negative ... concord?

    NARCIS (Netherlands)

    Giannakidou, A

    The main claim of this paper is that a general theory of negative concord (NC) should allow for the possibility of NC involving scoping of a universal quantifier above negation. I propose that Greek NC instantiates this option. Greek n-words will be analyzed as polarity sensitive universal

  8. Treadmill Running Ameliorates Destruction of Articular Cartilage and Subchondral Bone, Not Only Synovitis, in a Rheumatoid Arthritis Rat Model

    Directory of Open Access Journals (Sweden)

    Seiji Shimomura

    2018-06-01

    Full Text Available We analyzed the influence of treadmill running on rheumatoid arthritis (RA joints using a collagen-induced arthritis (CIA rat model. Eight-week-old male Dark Agouti rats were randomly divided into four groups: The control group, treadmill group (30 min/day for 4 weeks from 10-weeks-old, CIA group (induced CIA at 8-weeks-old, and CIA + treadmill group. Destruction of the ankle joint was evaluated by histological analyses. Morphological changes of subchondral bone were analyzed by μ-CT. CIA treatment-induced synovial membrane invasion, articular cartilage destruction, and bone erosion. Treadmill running improved these changes. The synovial membrane in CIA rats produced a large amount of tumor necrosis factor-α and Connexin 43; production was significantly suppressed by treadmill running. On μ-CT of the talus, bone volume fraction (BV/TV was significantly decreased in the CIA group. Marrow star volume (MSV, an index of bone loss, was significantly increased. These changes were significantly improved by treadmill running. Bone destruction in the talus was significantly increased with CIA and was suppressed by treadmill running. On tartrate-resistant acid phosphate and alkaline phosphatase (TRAP/ALP staining, the number of osteoclasts around the pannus was decreased by treadmill running. These findings indicate that treadmill running in CIA rats inhibited synovial hyperplasia and joint destruction.

  9. Comparison of vertical ground reaction forces during overground and treadmill running. A validation study

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    Kluitenberg Bas

    2012-11-01

    Full Text Available Abstract Background One major drawback in measuring ground-reaction forces during running is that it is time consuming to get representative ground-reaction force (GRF values with a traditional force platform. An instrumented force measuring treadmill can overcome the shortcomings inherent to overground testing. The purpose of the current study was to determine the validity of an instrumented force measuring treadmill for measuring vertical ground-reaction force parameters during running. Methods Vertical ground-reaction forces of experienced runners (12 male, 12 female were obtained during overground and treadmill running at slow, preferred and fast self-selected running speeds. For each runner, 7 mean vertical ground-reaction force parameters of the right leg were calculated based on five successful overground steps and 30 seconds of treadmill running data. Intraclass correlations (ICC(3,1 and ratio limits of agreement (RLOA were used for further analysis. Results Qualitatively, the overground and treadmill ground-reaction force curves for heelstrike runners and non-heelstrike runners were very similar. Quantitatively, the time-related parameters and active peak showed excellent agreement (ICCs between 0.76 and 0.95, RLOA between 5.7% and 15.5%. Impact peak showed modest agreement (ICCs between 0.71 and 0.76, RLOA between 19.9% and 28.8%. The maximal and average loading-rate showed modest to excellent ICCs (between 0.70 and 0.89, but RLOA were higher (between 34.3% and 45.4%. Conclusions The results of this study demonstrated that the treadmill is a moderate to highly valid tool for the assessment of vertical ground-reaction forces during running for runners who showed a consistent landing strategy during overground and treadmill running. The high stride-to-stride variance during both overground and treadmill running demonstrates the importance of measuring sufficient steps for representative ground-reaction force values. Therefore, an

  10. Treadmill exercise alleviates short-term memory impairment in 6-hydroxydopamine-induced Parkinson's rats.

    Science.gov (United States)

    Cho, Han-Sam; Shin, Mal-Soon; Song, Wook; Jun, Tae-Won; Lim, Baek-Vin; Kim, Young-Pyo; Kim, Chang-Ju

    2013-01-01

    Progressive loss of dopaminergic neurons in substantia nigra is a key pathogenesis of Parkinson's disease. In the present study, we investigated the effects of treadmill exercise on short-term memory, apoptotic dopaminergic neuronal cell death and fiber loss in the nigrostriatum, and cell proliferation in the hippocampal dentate gyrus of Parkinson's rats. Parkinson's rats were made by injection of 6-hydroxydopamine (6-OHDA) into the striatum using stereotaxic instrument. Four weeks after 6-OHDA injection, the rats in the 6-OHDA-injection group exhibited significant rotational asymmetry following apomorphine challenge. The rats in the exercise groups were put on the treadmill to run for 30 min once a day for 14 consecutive days starting 4 weeks after 6-OHDA injection. In the present results, extensive degeneration of the dopaminergic neurons in the substantia nigra with loss of dopaminergic fibers in the striatum were produced in the rats without treadmill running, which resulted in short-term memory impairment. However, the rats performing treadmill running for 2 weeks alleviated nigrostriatal dopaminergic cell loss and alleviated short-term memory impairment with increasing cell proliferation in the hippocampal dentate gyrus of Parkinson's rats. The present results show that treadmill exercise may provide therapeutic value for the Parkinson's disease.

  11. Human H-reflexes are smaller in difficult beam walking than in normal treadmill walking.

    Science.gov (United States)

    Llewellyn, M; Yang, J F; Prochazka, A

    1990-01-01

    Hoffman (H) reflexes were elicited from the soleus (SOL) muscle while subjects walked on a treadmill and on a narrow beam (3.5 cm wide, raised 34 cm from the floor). The speed of walking on the treadmill was selected for each subject to match the background activation level of their SOL muscle during beam walking. The normal reciprocal activation pattern of the tibialis anterior and SOL muscles in treadmill walking was replaced by a pattern dominated by co-contraction on the beam. In addition, the step cycle duration was more variable and the time spent in the swing phase was reduced on the beam. The H-reflexes were highly modulated in both tasks, the amplitude being high in the stance phase and low in the swing phase. The H-reflex amplitude was on average 40% lower during beam walking than treadmill walking. The relationship between the H-reflex amplitude and the SOL EMG level was quantified by a regression line relating the two variables. The slope of this line was on average 41% lower in beam walking than treadmill walking. The lower H-reflex gain observed in this study and the high level of fusimotor drive observed in cats performing similar tasks suggest that the two mechanisms which control the excitability of this reflex pathway (i.e. fusimotor action and control of transmission at the muscle spindle to moto-neuron synapse) may be controlled independently.

  12. Stepping responses to treadmill perturbations vary with severity of motor deficits in human SCI.

    Science.gov (United States)

    Chu, Virginia Way Tong; Hornby, T George; Schmit, Brian D

    2018-04-18

    In this study, we investigated the responses to tread perturbations during human stepping on a treadmill. Our approach was to test the effects of perturbations to a single leg using a split-belt treadmill in healthy participants and in participants with varying severity of spinal cord injury (SCI). We recruited 11 people with incomplete SCI and 5 noninjured participants. As participants walked on an instrumented treadmill, the belt on one side was stopped or accelerated briefly during mid to late stance. A majority of participants initiated an unnecessary swing when the treadmill was stopped in mid stance, although the likelihood of initiating a step was decreased in participants with more severe SCI. Accelerating or decelerating one belt of the treadmill during stance altered the characteristics of swing. We observed delayed swing initiation when the belt was decelerated (i.e. the hip was in a more flexed position at time of swing) and advanced swing initiation with acceleration (i.e. hip extended at swing initiation). Further, the timing and leg posture of heel strike appeared to remain constant, reflected by a sagittal plane hip angle at heel strike that remained the same regardless of the perturbation. In summary, our results supported the current understanding of the role of sensory feedback and central drive in the control of stepping in participants with incomplete SCI and noninjured participants. In particular, the observation of unnecessary swing during a stop perturbation highlights the interdependence of central and sensory drive in walking control.

  13. Using a Split-belt Treadmill to Evaluate Generalization of Human Locomotor Adaptation.

    Science.gov (United States)

    Vasudevan, Erin V L; Hamzey, Rami J; Kirk, Eileen M

    2017-08-23

    Understanding the mechanisms underlying locomotor learning helps researchers and clinicians optimize gait retraining as part of motor rehabilitation. However, studying human locomotor learning can be challenging. During infancy and childhood, the neuromuscular system is quite immature, and it is unlikely that locomotor learning during early stages of development is governed by the same mechanisms as in adulthood. By the time humans reach maturity, they are so proficient at walking that it is difficult to come up with a sufficiently novel task to study de novo locomotor learning. The split-belt treadmill, which has two belts that can drive each leg at a different speed, enables the study of both short- (i.e., immediate) and long-term (i.e., over minutes-days; a form of motor learning) gait modifications in response to a novel change in the walking environment. Individuals can easily be screened for previous exposure to the split-belt treadmill, thus ensuring that all experimental participants have no (or equivalent) prior experience. This paper describes a typical split-belt treadmill adaptation protocol that incorporates testing methods to quantify locomotor learning and generalization of this learning to other walking contexts. A discussion of important considerations for designing split-belt treadmill experiments follows, including factors like treadmill belt speeds, rest breaks, and distractors. Additionally, potential but understudied confounding variables (e.g., arm movements, prior experience) are considered in the discussion.

  14. Treadmill exercise ameliorates social isolation-induced depression through neuronal generation in rat pups.

    Science.gov (United States)

    Cho, Jung-Wan; Jung, Sun-Young; Lee, Sang-Won; Lee, Sam-Jun; Seo, Tae-Beom; Kim, Young-Pyo; Kim, Dae-Young

    2017-12-01

    Social isolation is known to induce emotional and behavioral changes in animals and humans. The effect of treadmill exercise on depression was investigated using social isolated rat pups. The rat pups in the social isolation groups were housed individually. The rat pups in the exercise groups were forced to run on treadmill for 30 min once a day from postnatal day 21 to postnatal day 34. In order to evaluate depression state of rat pups, forced swimming test was performed. Newly generated cells in the hippocampal dentate gyrus were determined by 5-bromo-2'-deoxyuridine (BrdU) immunohistochemistry. We examined the expression of 5-hydroxytryptamine (5-HT) and tryptophan hydroxylase (TPH) in the dorsal raphe using immunofluorescence. The expression of brain-derived neurotrophic factor (BDNF) and tyrosine kinase B (TrkB) was detected by Western blot analysis. The present results demonstrated that social isolation increased resting time and decreased mobility time. Expression of 5-HT and TPH in the dorsal raphe and expression of BDNF and TrkB in the hippocampus were decreased by social isolation. The number of BrdU-positive cells in the hippocampal dentate gyrus was suppressed by social isolation. Treadmill exercise decreased resting time and increased mobility in the social isolated rat pups. Expression of 5-HT, TPH, BDNF, and TrkB was increased by treadmill exercise. The present results suggested that treadmill exercise may ameliorates social isolation-induced depression through increasing neuronal generation.

  15. PENGARUH LATIHAN FARTLEK DENGAN TREADMILL DAN LARI DI LAPANGAN TERHADAP DAYA TAHAN KARDIORESPIRASI

    Directory of Open Access Journals (Sweden)

    Maya Kurnia

    2013-04-01

    Abstract The objective of this study is to reveal the effect of fartlek with treadmill, running, and vital lung capacity on respiratory endurance. The study used the experiment factorial 2x2 block design. The data were collected using the respiratory endurance test (using the twelve minutes by Cooper’s test with maximal distance which can be taken within twelve minutes. The results of this study are as follows: (1 There is a difference in respiratory endurance between those who were involved in fartlek with treadmill with those who ran. The respiratory endurance is better for those who ran than those who used treadmill. (2 There is a difference in respiratory endurance between those who have low vital lung capacity with those who have high vital lung capacity. The respiratory endurance is better for those who have high vital lung capacity than those who have low vital lung capacity. (3 There is no interaction between those who were involved in fartlek with treadmill, running, and vital lung capacity in respiratory endurance. Members who were involved in fartlek with ran and have low vital lung capacity, who were involved in fartlek with treadmill and have high vital lung capacity, and who were involved in fartlek with ran and have high vital lung capacity is not different significance. Keywords: fartlek training, vital lung capacity, respiratory endurance.

  16. Treadmill workstations: the effects of walking while working on physical activity and work performance.

    Directory of Open Access Journals (Sweden)

    Avner Ben-Ner

    Full Text Available We conducted a 12-month-long experiment in a financial services company to study how the availability of treadmill workstations affects employees' physical activity and work performance. We enlisted sedentary volunteers, half of whom received treadmill workstations during the first two months of the study and the rest in the seventh month of the study. Participants could operate the treadmills at speeds of 0-2 mph and could use a standard chair-desk arrangement at will. (a Weekly online performance surveys were administered to participants and their supervisors, as well as to all other sedentary employees and their supervisors. Using within-person statistical analyses, we find that overall work performance, quality and quantity of performance, and interactions with coworkers improved as a result of adoption of treadmill workstations. (b Participants were outfitted with accelerometers at the start of the study. We find that daily total physical activity increased as a result of the adoption of treadmill workstations.

  17. Mechanical Alterations Associated with Repeated Treadmill Sprinting under Heat Stress.

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    Olivier Girard

    Full Text Available Examine the mechanical alterations associated with repeated treadmill sprinting performed in HOT (38°C and CON (25°C conditions.Eleven recreationally active males performed a 30-min warm-up followed by three sets of five 5-s sprints with 25-s recovery and 3-min between sets in each environment. Constant-velocity running for 1-min at 10 and 20 km.h-1 was also performed prior to and following sprinting.Mean skin (37.2±0.7 vs. 32.7±0.8°C; P<0.001 and core (38.9±0.2 vs. 38.8±0.3°C; P<0.05 temperatures, together with thermal comfort (P<0.001 were higher following repeated sprinting in HOT vs. CON. Step frequency and vertical stiffness were lower (-2.6±1.6% and -5.5±5.5%; both P<0.001 and contact time (+3.2±2.4%; P<0.01 higher in HOT for the mean of sets 1-3 compared to CON. Running distance per sprint decreased from set 1 to 3 (-7.0±6.4%; P<0.001, with a tendency for shorter distance covered in HOT vs. CON (-2.7±3.4%; P = 0.06. Mean vertical (-2.6±5.5%; P<0.01, horizontal (-9.1±4.4%; P<0.001 and resultant ground reaction forces (-3.0±2.8%; P<0.01 along with vertical stiffness (-12.9±2.3%; P<0.001 and leg stiffness (-8.4±2.7%; P<0.01 decreased from set 1 to 3, independently of conditions. Propulsive power decreased from set 1 to 3 (-16.9±2.4%; P<0.001, with lower propulsive power values in set 2 (-6.6%; P<0.05 in HOT vs. CON. No changes in constant-velocity running patterns occurred between conditions, or from pre-to-post repeated-sprint exercise.Thermal strain alters step frequency and vertical stiffness during repeated sprinting; however without exacerbating mechanical alterations. The absence of changes in constant-velocity running patterns suggests a strong link between fatigue-induced velocity decrements during sprinting and mechanical alterations.

  18. Mechanical Alterations Associated with Repeated Treadmill Sprinting under Heat Stress

    Science.gov (United States)

    Brocherie, Franck; Morin, Jean-Benoit; Racinais, Sébastien; Millet, Grégoire P.; Périard, Julien D.

    2017-01-01

    Purpose Examine the mechanical alterations associated with repeated treadmill sprinting performed in HOT (38°C) and CON (25°C) conditions. Methods Eleven recreationally active males performed a 30-min warm-up followed by three sets of five 5-s sprints with 25-s recovery and 3-min between sets in each environment. Constant-velocity running for 1-min at 10 and 20 km.h-1 was also performed prior to and following sprinting. Results Mean skin (37.2±0.7 vs. 32.7±0.8°C; P<0.001) and core (38.9±0.2 vs. 38.8±0.3°C; P<0.05) temperatures, together with thermal comfort (P<0.001) were higher following repeated sprinting in HOT vs. CON. Step frequency and vertical stiffness were lower (-2.6±1.6% and -5.5±5.5%; both P<0.001) and contact time (+3.2±2.4%; P<0.01) higher in HOT for the mean of sets 1–3 compared to CON. Running distance per sprint decreased from set 1 to 3 (-7.0±6.4%; P<0.001), with a tendency for shorter distance covered in HOT vs. CON (-2.7±3.4%; P = 0.06). Mean vertical (-2.6±5.5%; P<0.01), horizontal (-9.1±4.4%; P<0.001) and resultant ground reaction forces (-3.0±2.8%; P<0.01) along with vertical stiffness (-12.9±2.3%; P<0.001) and leg stiffness (-8.4±2.7%; P<0.01) decreased from set 1 to 3, independently of conditions. Propulsive power decreased from set 1 to 3 (-16.9±2.4%; P<0.001), with lower propulsive power values in set 2 (-6.6%; P<0.05) in HOT vs. CON. No changes in constant-velocity running patterns occurred between conditions, or from pre-to-post repeated-sprint exercise. Conclusions Thermal strain alters step frequency and vertical stiffness during repeated sprinting; however without exacerbating mechanical alterations. The absence of changes in constant-velocity running patterns suggests a strong link between fatigue-induced velocity decrements during sprinting and mechanical alterations. PMID:28146582

  19. Persistent negative temperature response of mesophyll conductance in red raspberry (Rubus idaeus L.) leaves under both high and low vapour pressure deficits: a role for abscisic acid?

    Science.gov (United States)

    Qiu, Changpeng; Ethier, Gilbert; Pepin, Steeve; Dubé, Pascal; Desjardins, Yves; Gosselin, André

    2017-09-01

    The temperature dependence of mesophyll conductance (g m ) was measured in well-watered red raspberry (Rubus idaeus L.) plants acclimated to leaf-to-air vapour pressure deficit (VPDL) daytime differentials of contrasting amplitude, keeping a fixed diurnal leaf temperature (T leaf ) rise from 20 to 35 °C. Contrary to the great majority of g m temperature responses published to date, we found a pronounced reduction of g m with increasing T leaf irrespective of leaf chamber O 2 level and diurnal VPDL regime. Leaf hydraulic conductance was greatly enhanced during the warmer afternoon periods under both low (0.75 to 1.5 kPa) and high (0.75 to 3.5 kPa) diurnal VPDL regimes, unlike stomatal conductance (g s ), which decreased in the afternoon. Consequently, the leaf water status remained largely isohydric throughout the day, and therefore cannot be evoked to explain the diurnal decrease of g m . However, the concerted diurnal reductions of g m and g s were well correlated with increases in leaf abscisic acid (ABA) content, thus suggesting that ABA can induce a significant depression of g m under favourable leaf water status. Our results challenge the view that the temperature dependence of g m can be explained solely from dynamic leaf anatomical adjustments and/or from the known thermodynamic properties of aqueous solutions and lipid membranes.​. © 2017 John Wiley & Sons Ltd.

  20. Water depth effects on impact loading, kinematic and physiological variables during water treadmill running.

    Science.gov (United States)

    Macdermid, Paul W; Wharton, Josh; Schill, Carina; Fink, Philip W

    2017-07-01

    The purpose of this study was to compare impact loading, kinematic and physiological responses to three different immersion depths (mid-shin, mid-thigh, and xiphoid process) while running at the same speed on a water based treadmill. Participants (N=8) ran on a water treadmill at three depths for 3min. Tri-axial accelerometers were used to identify running dynamics plus measures associated with impact loading rates, while heart rate data were logged to indicate physiological demand. Participants had greater peak impact accelerations (prunning immersed to the xiphoid process. Physiological effort determined by heart rate was also significantly less (prunning immersed to the xiphoid process. Water immersed treadmill running above the waistline alters kinematics of gait, reduces variables associated with impact, while decreasing physiological demand compared to depths below the waistline. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Impact of enhanced sensory input on treadmill step frequency: infants born with myelomeningocele.

    Science.gov (United States)

    Pantall, Annette; Teulier, Caroline; Smith, Beth A; Moerchen, Victoria; Ulrich, Beverly D

    2011-01-01

    To determine the effect of enhanced sensory input on the step frequency of infants with myelomeningocele (MMC) when supported on a motorized treadmill. Twenty-seven infants aged 2 to 10 months with MMC lesions at, or caudal to, L1 participated. We supported infants upright on the treadmill for 2 sets of 6 trials, each 30 seconds long. Enhanced sensory inputs within each set were presented in random order and included baseline, visual flow, unloading, weights, Velcro, and friction. Overall friction and visual flow significantly increased step rate, particularly for the older subjects. Friction and Velcro increased stance-phase duration. Enhanced sensory input had minimal effect on leg activity when infants were not stepping. : Increased friction via Dycem and enhancing visual flow via a checkerboard pattern on the treadmill belt appear to be more effective than the traditional smooth black belt surface for eliciting stepping patterns in infants with MMC.

  2. The Rise of the Food Risk Society and the Changing Nature of the Technological Treadmill

    Directory of Open Access Journals (Sweden)

    Lioudmila Chatalova

    2016-06-01

    Full Text Available Economic development of transition and developed countries is associated with increasingly unhealthy dietary habits among low-income population segments. Drawing on Ulrich Beck’s sociological theory of risk society, the present research note calls attention to the positive relation between national economic development and food risks that result in the rise of food-related diseases and healthcare costs. On this basis, we argue that the knowledge-intensive agribusiness may translate Cochrane’s technological treadmill into Beck’s risk treadmill that shifts a growing share of food-related healthcare costs from producers toward consumers, state, and the healthcare system. This argument motivates a novel research program dealing with the “food risk treadmill” that emerges in response to modern farming and agribusiness practices. Awareness of the food risk treadmill may help to streamline the development of agricultural science and to prevent it from being excessively dominated by the agricultural and food industry.

  3. Tratamiento mediante terapia de presión negativa VAC® de herida infectada tras artrodesis raquídea Treatment of infected wound secondary to spinal arthrodesis with negative pressure therapy VAC®

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    V. Yuste Benavente

    2011-12-01

    Full Text Available Las complicaciones cutáneas secundarias a artrodesis raquídea son un problema frecuente que requiere la colaboración de los Servicios de Cirugía Plástica y en cuyo tratamiento la terapia de presión negativa puede resultar útil. En este artículo presentamos el caso de un paciente afectado por metástasis vertebrales de adenocarcinoma gástrico que requirió artrodesis raquídea y desarrolló posteriormente una úlcera por presión dorsal debido al material implantado. El sistema VAC® permitió la limpieza y disminución de tamaño de la lesión, siendo posible la cobertura posterior de la misma con un colgajo miocutáneo de dorsal ancho. En este artículo discutimos la utilidad de la terapia de presión negativa en este tipo de lesiones.Cutaneous complications secondary to spinal fusion are a common problem that requires the collaboration of the Department of Plastic Surgery and in which negative pressure therapy treatment may be useful. In this paper we present the case of a patient with spinal metastases secondary to gastric adenocarcinoma that required spinal fusion and developed a dorsal pressure ulcer secondary to the implanted material. VAC® therapy system allowed cleaning the wound and decreasing the size of the injury, thus making it possible subsequently to cover it with a latissimus dorsi myocutaneous flap. In this paper we discuss the usefulness of negative pressure therapy in this type of injury.

  4. Metabolic cost of running is greater on a treadmill with a stiffer running platform.

    Science.gov (United States)

    Smith, James A H; McKerrow, Alexander D; Kohn, Tertius A

    2017-08-01

    Exercise testing on motorised treadmills provides valuable information about running performance and metabolism; however, the impact of treadmill type on these tests has not been investigated. This study compared the energy demand of running on two laboratory treadmills: an HP Cosmos (C) and a Quinton (Q) model, with the latter having a 4.5 times stiffer running platform. Twelve experienced runners ran identical bouts on these treadmills at a range of four submaximal velocities (reported data is for the velocity that approximated 75-81% VO 2max ). The stiffer treadmill elicited higher oxygen consumption (C: 46.7 ± 3.8; Q: 50.1 ± 4.3 ml·kg -1 · min -1 ), energy expenditure (C: 16.0 ± 2.5; Q: 17.7 ± 2.9 kcal · min -1 ), carbohydrate oxidation (C: 9.6 ± 3.1; Q: 13.0 ± 3.9 kcal · min -1 ), heart rate (C: 155 ± 16; Q: 163 ± 16 beats · min -1 ) and rating of perceived exertion (C: 13.8 ± 1.2; Q: 14.7 ± 1.2), but lower fat oxidation (C: 6.4 ± 2.3; Q: 4.6 ± 2.5 kcal · min -1 ) (all analysis of variance treadmill comparisons P running depending on the running platform stiffness.

  5. Cardiac function and myocardial perfusion immediately following maximal treadmill exercise inside the MRI room

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    Ballinger Michelle R

    2008-01-01

    Full Text Available Abstract Treadmill exercise stress testing is an essential tool in the prevention, detection, and treatment of a broad spectrum of cardiovascular disease. After maximal exercise, cardiac images at peak stress are typically acquired using nuclear scintigraphy or echocardiography, both of which have inherent limitations. Although CMR offers superior image quality, the lack of MRI-compatible exercise and monitoring equipment has prevented the realization of treadmill exercise CMR. It is critical to commence imaging as quickly as possible after exercise to capture exercise-induced cardiac wall motion abnormalities. We modified a commercial treadmill such that it could be safely positioned inside the MRI room to minimize the distance between the treadmill and the scan table. We optimized the treadmill exercise CMR protocol in 20 healthy volunteers and successfully imaged cardiac function and myocardial perfusion at peak stress, followed by viability imaging at rest. Imaging commenced an average of 30 seconds after maximal exercise. Real-time cine of seven slices with no breath-hold and no ECG-gating was completed within 45 seconds of exercise, immediately followed by stress perfusion imaging of three short-axis slices which showed an average time to peak enhancement within 57 seconds of exercise. We observed a 3.1-fold increase in cardiac output and a myocardial perfusion reserve index of 1.9, which agree with reported values for healthy subjects at peak stress. This study successfully demonstrates in-room treadmill exercise CMR in healthy volunteers, but confirmation of feasibility in patients with heart disease is still needed.

  6. Comparison of the metabolic energy cost of overground and treadmill walking in older adults.

    Science.gov (United States)

    Berryman, Nicolas; Gayda, Mathieu; Nigam, Anil; Juneau, Martin; Bherer, Louis; Bosquet, Laurent

    2012-05-01

    We assessed whether the metabolic energy cost of walking was higher when measured overground or on a treadmill in a population of healthy older adults. We also assessed the association between the two testing modes. Participants (n = 20, 14 men and 6 women aged between 65 and 83 years of age) were randomly divided into two groups. Half of them went through the overground-treadmill sequence while the other half did the opposite order. A familiarization visit was held for each participant prior to the actual testing. For both modes of testing, five walking speeds were experimented (0.67, 0.89, 1.11, 1.33 and 1.67 m s(-1)). Oxygen uptake was monitored for all walking speeds. We found a significant difference between treadmill and track metabolic energy cost of walking, whatever the walking speed. The results show that walking on the treadmill requires more metabolic energy than walking overground for all experimental speeds (P < 0.05). The association between both measures was low to moderate (0.17 < ICC < 0.65), and the standard error of measurement represented 6.9-15.7% of the average value. These data indicate that metabolic energy cost of walking results from a treadmill test does not necessarily apply in daily overground activities. Interventions aiming at reducing the metabolic energy cost of walking should be assessed with the same mode as it was proposed during the intervention. If the treadmill mode is necessary for any purposes, functional overground walking tests should be implemented to obtain a more complete and specific evaluation.

  7. Aerobic endurance in HIV-positive young adults and HIV-negative ...

    African Journals Online (AJOL)

    2015-03-09

    Mar 9, 2015 ... not taking antiretroviral medication and 78 HIV-negative participants (45 ... between groups were adjusted for age differences using analysis of ... habits, body composition, gender, age and genetic factors ..... Three meta - analyses ... Exercise Treadmill Test for the Assessment of Cardiac Risk Markers.

  8. Observations of different core water cluster ions Y-(H2O)n (Y = O2, HOx, NOx, COx) and magic number in atmospheric pressure negative corona discharge mass spectrometry.

    Science.gov (United States)

    Sekimoto, Kanako; Takayama, Mitsuo

    2011-01-01

    Reliable mass spectrometry data from large water clusters Y(-)(H(2)O)(n) with various negative core ions Y(-) such as O(2)(-), HO(-), HO(2)(-), NO(2)(-), NO(3)(-), NO(3)(-)(HNO(3))(2), CO(3)(-) and HCO(4)(-) have been obtained using atmospheric pressure negative corona discharge mass spectrometry. All the core Y(-) ions observed were ionic species that play a central role in tropospheric ion chemistry. These mass spectra exhibited discontinuities in ion peak intensity at certain size clusters Y(-)(H(2)O)(m) indicating specific thermochemical stability. Thus, Y(-)(H(2)O)(m) may correspond to the magic number or first hydrated shell in the cluster series Y(-)(H(2)O)(n). The high intensity discontinuity at HO(-)(H(2)O)(3) observed was the first mass spectrometric evidence for the specific stability of HO(-)(H(2)O)(3) as the first hydrated shell which Eigen postulated in 1964. The negative ion water clusters Y(-)(H(2)O)(n) observed in the mass spectra are most likely to be formed via core ion formation in the ambient discharge area (760 torr) and the growth of water clusters by adiabatic expansion in the vacuum region of the mass spectrometers (≈1 torr). The detailed mechanism of the formation of the different core water cluster ions Y(-)(H(2)O)(n) is described. Copyright © 2010 John Wiley & Sons, Ltd.

  9. Gait Complexity and Regularity Are Differently Modulated by Treadmill Walking in Parkinson's Disease and Healthy Population

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    Thibault Warlop

    2018-02-01

    Full Text Available Variability raises considerable interest as a promising and sensitive marker of dysfunction in physiology, in particular in neurosciences. Both internally (e.g., pathology and/or externally (e.g., environment generated perturbations and the neuro-mechanical responses to them contribute to the fluctuating dynamics of locomotion. Defective internal gait control in Parkinson's disease (PD, resulting in typical timing gait disorders, is characterized by the breakdown of the temporal organization of stride duration variability. Influence of external cue on gait pattern could be detrimental or advantageous depending on situations (healthy or pathological gait pattern, respectively. As well as being an interesting rehabilitative approach in PD, treadmills are usually implemented in laboratory settings to perform instrumented gait analysis including gait variability assessment. However, possibly acting as an external pacemaker, treadmill could modulate the temporal organization of gait variability of PD patients which could invalidate any gait variability assessment. This study aimed to investigate the immediate influence of treadmill walking (TW on the temporal organization of stride duration variability in PD and healthy population. Here, we analyzed the gait pattern of 20 PD patients and 15 healthy age-matched subjects walking on overground and on a motorized-treadmill (randomized order at a self-selected speed. The temporal organization and regularity of time series of walking were assessed on 512 consecutive strides and assessed by the application of non-linear mathematical methods (i.e., the detrended fluctuation analysis and power spectral density; and sample entropy, for the temporal organization and regularity of gait variability, respectively. A more temporally organized and regular gait pattern seems to emerge from TW in PD while no influence was observed on healthy gait pattern. Treadmill could afford the necessary framework to regulate gait

  10. Biomechanics of the Treadmill Locomotion on the International Space Station

    Science.gov (United States)

    DeWitt, John; Cromwell, R. L.; Ploutz-Snyder, L. L.

    2014-01-01

    Exercise prescriptions completed by International Space Station (ISS) crewmembers are typically based upon evidence obtained during ground-based investigations, with the assumption that the results of long-term training in weightlessness will be similar to that attained in normal gravity. Coupled with this supposition are the assumptions that exercise motions and external loading are also similar between gravitational environments. Normal control of locomotion is dependent upon learning patterns of muscular activation and requires continual monitoring of internal and external sensory input [1]. Internal sensory input includes signals that may be dependent on or independent of gravity. Bernstein hypothesized that movement strategy planning and execution must include the consideration of segmental weights and inertia [2]. Studies of arm movements in microgravity showed that individuals tend to make errors but that compensation strategies result in adaptations, suggesting that control mechanisms must include peripheral information [3-5]. To date, however, there have been no studies examining a gross motor activity such as running in weightlessness other than using microgravity analogs [6-8]. The objective of this evaluation was to collect biomechanical data from crewmembers during treadmill exercise before and during flight. The goal was to determine locomotive biomechanics similarities and differences between normal and weightless environments. The data will be used to optimize future exercise prescriptions. This project addresses the Critical Path Roadmap risks 1 (Accelerated Bone Loss and Fracture Risk) and 11 (Reduced Muscle Mass, Strength, and Endurance). Data were collected from 7 crewmembers before flight and during their ISS missions. Before launch, crewmembers performed a single data collection session at the NASA Johnson Space Center. Three-dimensional motion capture data were collected for 30 s at speeds ranging from 1.5 to 9.5 mph in 0.5 mph increments

  11. Acute and chronic effects of aquatic treadmill training on land treadmill running kinematics: A cross-over and single-subject design approach.

    Science.gov (United States)

    Bressel, Eadric; Louder, Talin J; Hoover, James P; Roberts, Luke C; Dolny, Dennis G

    2017-11-01

    The aim of this study was to determine if selected kinematic measures (foot strike index [SI], knee contact angle and overstride angle) were different between aquatic treadmill (ATM) and land treadmill (LTM) running, and to determine if these measures were altered during LTM running as a result of 6 weeks of ATM training. Acute effects were tested using 15 competitive distance runners who completed 1 session of running on each treadmill type at 5 different running speeds. Subsequently, three recreational runners completed 6 weeks of ATM training following a single-subject baseline, intervention and withdrawal experiment. Kinematic measures were quantified from digitisation of video. Regardless of speed, SI values during ATM running (61.3 ± 17%) were significantly greater (P = 0.002) than LTM running (42.7 ± 23%). Training on the ATM did not change (pre/post) the SI (26 ± 3.2/27 ± 3.1), knee contact angle (165 ± 0.3/164 ± 0.8) or overstride angle (89 ± 0.4/89 ± 0.1) during LTM running. Although SI values were different between acute ATM and LTM running, 6 weeks of ATM training did not appear to alter LTM running kinematics as evidenced by no change in kinematic values from baseline to post intervention assessments.

  12. Effects of treadmill inclination on electromyographic activity and hind limb kinematics in healthy hounds at a walk.

    Science.gov (United States)

    Lauer, Susanne K; Hillman, Robert B; Li, Li; Hosgood, Giselle L

    2009-05-01

    To evaluate the effect of treadmill incline on muscle activity and joint range of motion (ROM) in hind limbs of dogs. 8 purpose-bred healthy adult hounds. Activities of the hamstring (semimembranosus, semitendinosus, and biceps femoris muscles), gluteal (superficial, middle, and deep gluteal muscles), and quadriceps (femoris, vastus lateralis, vastus intermedius, and vastus medialis muscles) muscle groups and hip and stifle joint ROM were measured with surface electrogoniometric and myographic sensors in hounds walking on a treadmill at 0.54 m/s at inclines of 5%, 0%, and -5% in random order. Mean electromyographic activities and mean ROMs at each inclination were compared for swing and stance phases. Treadmill inclination did not affect duration of the stance and swing phases or the whole stride. When treadmill inclination was increased from -5% to 5%, hip joint ROM increased and the degree of stifle joint extension decreased significantly. In the beginning of the stance phase, activity of the hamstring muscle group was significantly increased when walking at a 5% incline versus a 5% decline. In the end of the stance phase, that activity was significantly increased when walking at a 5% incline versus at a 5% decline or on a flat surface. Activity of the gluteal and quadriceps muscle groups was not affected when treadmill inclination changed. Treadmill inclination affected joint kinematics only slightly. Walking on a treadmill at a 5% incline had more potential to strengthen the hamstring muscle group than walking on a treadmill with a flat or declined surface.

  13. Effects of treadmill training with the eyes closed on gait and balance ability of chronic stroke patients.

    Science.gov (United States)

    Kim, Yong-Wook; Moon, Sung-Jun

    2015-09-01

    [Purpose] The purpose of this study was to compare the effect of treadmill walking with the eyes closed and open on the gait and balance abilities of chronic stroke patients. [Subjects and Methods] Thirty patients with chronic stroke participated in this study. The treadmill gait training for each group lasted 40 minutes, and sessions were held 3 times a week for 4 weeks. Gait ability was measured using a Biodex Gait Trainer Treadmill System. Balance ability was measured using a Biodex Balance System. [Results] After the treadmill training' the treadmill training with eyes closed (TEC) group showed significant improvements in walking distance' step length' coefficient of variation' and limit of stability (overall' lateral affected' forward lateral unaffected) compared to the treadmill training with eyes open (TEO) group. [Conclusion] The walking and balance abilities of the TEC participants showed more improvement after the treadmill walking sessions than those of the TEO participants. Therefore' treadmill walking with visual deprivation may be useful for the rehabilitation of patients with chronic stroke.

  14. Edema pulmonar por pressão negativa após extubação traqueal: relato de caso Negative pressure pulmonary edema after tracheal extubation: case report

    Directory of Open Access Journals (Sweden)

    Fabiano Timbó Barbosa

    2007-03-01

    Full Text Available JUSTIFICATIVA E OBJETIVOS: O edema pulmonar por pressão negativa após obstrução de via aérea é atualmente uma entidade bem descrita, porém pouco diagnosticada e com poucos casos relatados. O objetivo deste artigo foi relatar um caso de edema pulmonar por pressão negativa (EPPN após extubação traqueal com sucesso terapêutico, após uso de ventilação mecânica não-invasiva com pressão positiva. RELATO DO CASO: Paciente do sexo feminino, 22 anos, foi submetida à colecistectomia aberta. Os exames pré-operatórios encontravam-se sem alterações. Imediatamente após extubação a paciente apresentou dispnéia súbita e crepitações pulmonares. Foi iniciado tratamento para edema agudo de pulmão com oxigenoterapia sob máscara de Venturi, elevação do tórax e diurético. A paciente foi encaminhada a UTI devido a falha no tratamento. Ao chegar a UTI foi iniciada ventilação mecânica não-invasiva (VMNI com pressão de suporte (15 cmH2O e pressão expiratória final positiva (5 cmH2O com resolução dos sintomas. A paciente foi mantida em observação por mais 24 horas depois do evento com boas condições e recebeu alta para o quarto sem sintomas. CONCLUSÕES: O EPPN é uma entidade de difícil diagnóstico e deverá ser observada sempre que os pacientes evoluem com sinais e sintomas de insuficiência respiratória pós-extubação. Esta paciente se beneficiou de VMNI, mas caso haja falha terapêutica, a intubação traqueal e o suporte ventilatório mecânico invasivo deverão ser instituídos para melhor oxigenação dos pacientes.BACKGROUND AND OBJECTIVES: Negative pressure pulmonary edema after acute upper airway obstruction is a well-described event, thought infrequently diagnosed and reported. This report aimed at presenting a case of postextubation negative pressure pulmonary edema refractory to use of diuretics and with successful therapeutic after using positive pressure noninvasive mechanic ventilation. CASE REPORT: A

  15. Negative CO

    NARCIS (Netherlands)

    Meysman, F.J.R.; Montserrat, F.

    2017-01-01

    Negative emission technologies (NETs) target the removal of carbon dioxide (CO2) from the atmosphere, and are being actively investigated as a strategy to limit global warming to within the 1.5–2°C targets of the 2015 UN climate agreement. Enhanced silicate weathering (ESW) proposes to

  16. Negative Certainty

    Science.gov (United States)

    Ariso, José María

    2017-01-01

    The definitions of "negative knowledge" and the studies in this regard published to date have not considered the categorial distinction Wittgenstein established between knowledge and certainty. Hence, the important role that certainty, despite its omission, should have in these definitions and studies has not yet been shown. In this…

  17. Negative Pressure Wound Therapy Followed by Basic Fibroblast Growth Factor Spray as a Recovery Technique in Partial Necrosis of Distally Based Sural Flap for Calcaneal Osteomyelitis: A Case Report.

    Science.gov (United States)

    Mikami, Taro; Kaida, Eriko; Yabuki, Yuichiro; Kitamura, Sho; Kokubo, Ken'ichi; Maegawa, Jiro

    2018-03-28

    The distally based sural flap is regarded as the first choice for reconstruction in the distal part of the lower leg because the flap is easy to raise, reliable in its blood supply, and prone to only a few complications. Limited data have investigated the details of treatment in cases of failure of distally based sural flaps. We report a case of calcaneal osteomyelitis in which a successful outcome was finally obtained with a partially necrosed, distally based sural flap using negative pressure wound therapy with basic fibroblast growth factor spray. The 2-year follow-up examination was uneventful. Moreover, the patient was able to walk freely with an ankle-foot orthosis in her house. This technique can be considered as a useful and effective option to recover unfavorable results of distally based sural flaps. Copyright © 2017 The American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  18. Beyond the Hedonic Treadmill: Revising the Adaptation Theory of Well-Being

    Science.gov (United States)

    Diener, Ed; Lucas, Richard E.; Napa, Christine

    2006-01-01

    According to the hedonic treadmill model, good and bad events temporarily affect happiness, but people quickly adapt back to hedonic neutrality. The theory, which has gained widespread acceptance in recent years, implies that individual and societal efforts to increase happiness are doomed to failure. The recent empirical work outlined here…

  19. Treadmill sideways gait training with visual blocking for patients with brain lesions.

    Science.gov (United States)

    Kim, Tea-Woo; Kim, Yong-Wook

    2014-09-01

    [Purpose] The aim of this study was to verify the effect of sideways treadmill training with and without visual blocking on the balance and gait function of patients with brain lesions. [Subjects] Twenty-four stroke and traumatic brain injury subjects participated in this study. They were divided into two groups: an experimental group (12 subjects) and a control group (12 subjects). [Methods] Each group executed a treadmill training session for 20 minutes, three times a week, for 6 weeks. The sideways gait training on the treadmill was performed with visual blocking by the experimental group and with normal vision by the control group. A Biodex Gait Trainer 2 was used to assess the gait function. It was used to measure walking speed, walking distance, step length, and stance time on each foot. The Five-Times-Sit-To-Stand test (FTSST) and Timed Up and Go test (TUG) were used as balance measures. [Results] The sideways gait training with visual blocking group showed significantly improved walking speed, walking distance, step length, and stance time on each foot after training; FTSST and TUG times also significantly improved after training in the experimental group. Compared to the control group, the experimental group showed significant increases in stance time on each foot. [Conclusion] Sideways gait training on a treadmill with visual blocking performed by patients with brain lesions significantly improved their balance and gait function.

  20. Cardiac Autonomic Function during Submaximal Treadmill Exercise in Adults with Down Syndrome

    Science.gov (United States)

    Mendonca, Goncalo V.; Pereira, Fernando D.; Fernhall, Bo

    2011-01-01

    This study determined whether the cardiac autonomic function of adults with Down syndrome (DS) differs from that of nondisabled persons during submaximal dynamic exercise. Thirteen participants with DS and 12 nondisabled individuals performed maximal and submaximal treadmill tests with metabolic and heart rate (HR) measurements. Spectral analysis…

  1. Quantifying Gait Impairment Using an Instrumented Treadmill in People with Multiple Sclerosis

    Science.gov (United States)

    Kalron, Alon; Dvir, Zeevi; Frid, Lior; Achiron, Anat

    2013-01-01

    Background and Objective. Treadmill gait analysis has been proposed as an attractive alternative for overground walking measuring systems. The purpose of this study was twofold: first to determine spatiotemporal parameters of treadmill gait in patients with multiple sclerosis (MS) and second to examine whether these parameters are associated with specific functional impairments in this cohort. Method. Eighty-seven relapsing-remitting patients diagnosed with MS, 50 women and 37 men, aged 40.9 ± 11.9 with an expanded disability status scale (EDSS) score of 2.7 ± 1.6, participated in this study. Twenty-five apparently healthy subjects, 14 women and 11 men, aged 38.5 ± 9.4, served as controls. Spatiotemporal gait parameters were obtained using the Zebris FDM-T Treadmill (Zebris Medical GmbH, Germany). People with MS demonstrated significantly shorter steps, extended stride time, wider base of support, longer step time, reduced single support phase, and a prolonged double support phase compared to the healthy controls. The EDSS score was significantly correlated with all spatiotemporal gait parameters. Conclusion. The instrumented treadmill may be an effective tool in assessing ambulation capabilities of people with MS. PMID:23878746

  2. Use of an antigravity treadmill for rehabilitation of a pelvic stress injury.

    Science.gov (United States)

    Tenforde, Adam S; Watanabe, Laine M; Moreno, Tamara J; Fredericson, Michael

    2012-08-01

    Pelvic stress injuries are a relatively uncommon form of injury that require high index of clinician suspicion and usually MRI for definitive diagnosis. We present a case report of a 21-year-old female elite runner who was diagnosed with pelvic stress injury and used an antigravity treadmill during rehabilitation. She was able to return to pain-free ground running at 8 weeks after running at 95% body weight on the antigravity treadmill. Ten weeks from time of diagnosis, she competed at her conference championships and advanced to the NCAA Championships in the 10,000-meters. She competed in both races without residual pain. To our knowledge, this is the first published case report on use of an antigravity treadmill in rehabilitation of bone-related injuries. Our findings suggest that use of an antigravity treadmill for rehabilitation of a pelvic stress injury may result in appropriate bone loading and healing during progression to ground running and faster return to competition. Future research may identify appropriate protocols for recovery from overuse lower extremity injuries and other uses for this technology, including neuromuscular recovery and injury prevention. Copyright © 2012 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

  3. Long-term moderate treadmill exercise promotes stress-coping strategies in male and female rats.

    Science.gov (United States)

    Lalanza, Jaume F; Sanchez-Roige, Sandra; Cigarroa, Igor; Gagliano, Humberto; Fuentes, Silvia; Armario, Antonio; Capdevila, Lluís; Escorihuela, Rosa M

    2015-11-05

    Recent evidence has revealed the impact of exercise in alleviating anxiety and mood disorders; however, the exercise protocol that exerts such benefit is far from known. The current study was aimed to assess the effects of long-term moderate exercise on behavioural coping strategies (active vs. passive) and Hypothalamic-Pituitary-Adrenal response in rats. Sprague-Dawley male and female rats were exposed to 32-weeks of treadmill exercise and then tested for two-way active avoidance learning (shuttle-box). Two groups were used as controls: a non-handled sedentary group, receiving no manipulation, and a control group exposed to a stationary treadmill. Female rats displayed shorter escape responses and higher number of avoidance responses, reaching criterion for performance earlier than male rats. In both sexes, exercise shortened escape latencies, increased the total number of avoidances and diminished the number of trials needed to reach criterion for performance. Those effects were greater during acquisition in female rats, but remained over the shuttle-box sessions in treadmill trained male rats. In females, exercise did not change ACTH and corticosterone levels after shuttle-box acquisition. Collectively, treadmill exercise improved active coping strategies in a sex-dependent manner. In a broader context, moderate exercise could serve as a therapeutic intervention for anxiety and mood disorders.

  4. Exercise capacity in Dutch children : New reference values for the Bruce treadmill protocol

    NARCIS (Netherlands)

    M.H.M. van der Cammen-van Zijp (Monique); H.J.G. van den Berg-Emons (Rita); S.P. Willemsen (Sten); H.J. Stam (Henk); D. Tibboel (Dick); H. IJsselstijn (Hanneke)

    2010-01-01

    textabstractThe Bruce treadmill protocol is suitable for children 4 years of age and older. Dutch reference values were established in 1987. We considered that children's exercise capacity has deteriorated due to changes in physical activity patterns and eating habits. We determined new reference

  5. Analysis of gait using a treadmill and a Time-of-flight camera

    DEFF Research Database (Denmark)

    Jensen, Rasmus Ramsbøl; Paulsen, Rasmus Reinhold; Larsen, Rasmus

    2009-01-01

    We present a system that analyzes human gait using a treadmill and a Time-of-flight camera. The camera provides spatial data with local intensity measures of the scene, and data are collected over several gait cycles. These data are then used to model and analyze the gait. For each frame...

  6. Effect of Constraint Loading on the Lower Limb Muscle Forces in Weightless Treadmill Exercise

    Directory of Open Access Journals (Sweden)

    Ning Guo

    2018-01-01

    Full Text Available Long exposure to the microgravity will lead to muscle atrophy and bone loss. Treadmill exercise could mitigate the musculoskeletal decline. But muscle atrophy remains inevitable. The constraint loading applied on astronauts could affect the muscle force and its atrophy severity. However, the quantitative correlation between constraint loading mode and muscle forces remains unclear. This study aimed to characterize the influence of constraint loading mode on the lower limb muscle forces in weightless treadmill exercise. The muscle forces in the full gait cycle were calculated with the inverse dynamic model of human musculoskeletal system. The calculated muscle forces at gravity were validated with the EMG data. Muscle forces increased at weightlessness compared with those at the earth’s gravity. The increasing percentage from high to low is as follows: biceps femoris, gastrocnemius, soleus, vastus, and rectus femoris, which was in agreement with the muscle atrophy observed in astronauts. The constraint loading mode had an impact on the muscle forces in treadmill exercise and thus could be manipulated to enhance the effect of the muscle training in spaceflight. The findings could provide biomechanical basis for the optimization of treadmill constraint system and training program and improve the countermeasure efficiency in spaceflight.

  7. Exercise testing of pre-school children using the Bruce treadmill protocol: new reference values

    NARCIS (Netherlands)

    M.H.M. van der Cammen-van Zijp (Monique); H. IJsselstijn (Hanneke); T. Takken (Tim); S.P. Willemsen (Sten); D. Tibboel (Dick); H.J. Stam (Henk); H.J.G. van den Berg-Emons (Rita)

    2010-01-01

    textabstractThe Bruce treadmill protocol is an often-used exercise test for children and adults. Few and mainly old normative data are available for young children. In this cross-sectional observational study we determined new reference values for the original Bruce protocol in children aged 4 and 5

  8. Treadmill Training with Partial Body-Weight Support in Children with Cerebral Palsy: A Systematic Review

    Science.gov (United States)

    Mutlu, Akmer; Krosschell, Kristin; Spira, Deborah Gaebler

    2009-01-01

    OKAim: The aim of this systematic review was to examine the literature on the effects of partial body-weight support treadmill training (PBWSTT) in children with cerebral palsy (CP) on functional outcomes and attainment of ambulation. Method: We searched the relevant literature from 1950 to July 2007. We found eight studies on the use of PWSBTT on…

  9. A public dataset of overground and treadmill walking kinematics and kinetics in healthy individuals

    Directory of Open Access Journals (Sweden)

    Claudiane A. Fukuchi

    2018-04-01

    Full Text Available In a typical clinical gait analysis, the gait patterns of pathological individuals are commonly compared with the typically faster, comfortable pace of healthy subjects. However, due to potential bias related to gait speed, this comparison may not be valid. Publicly available gait datasets have failed to address this issue. Therefore, the goal of this study was to present a publicly available dataset of 42 healthy volunteers (24 young adults and 18 older adults who walked both overground and on a treadmill at a range of gait speeds. Their lower-extremity and pelvis kinematics were measured using a three-dimensional (3D motion-capture system. The external forces during both overground and treadmill walking were collected using force plates and an instrumented treadmill, respectively. The results include both raw and processed kinematic and kinetic data in different file formats: c3d and ASCII files. In addition, a metadata file is provided that contain demographic and anthropometric data and data related to each file in the dataset. All data are available at Figshare (DOI: 10.6084/m9.figshare.5722711. We foresee several applications of this public dataset, including to examine the influences of speed, age, and environment (overground vs. treadmill on gait biomechanics, to meet educational needs, and, with the inclusion of additional participants, to use as a normative dataset.

  10. Comparison of vertical ground reaction forces during overground and treadmill running. A validation study

    NARCIS (Netherlands)

    Kluitenberg, Bas; Bredeweg, Steef W.; Zijlstra, Sjouke; Zijlstra, Wiebren; Buist, Ida

    2012-01-01

    Background: One major drawback in measuring ground-reaction forces during running is that it is time consuming to get representative ground-reaction force (GRF) values with a traditional force platform. An instrumented force measuring treadmill can overcome the shortcomings inherent to overground

  11. A novel walking speed estimation scheme and its application to treadmill control for gait rehabilitation.

    Science.gov (United States)

    Yoon, Jungwon; Park, Hyung-Soon; Damiano, Diane Louise

    2012-08-28

    Virtual reality (VR) technology along with treadmill training (TT) can effectively provide goal-oriented practice and promote improved motor learning in patients with neurological disorders. Moreover, the VR + TT scheme may enhance cognitive engagement for more effective gait rehabilitation and greater transfer to over ground walking. For this purpose, we developed an individualized treadmill controller with a novel speed estimation scheme using swing foot velocity, which can enable user-driven treadmill walking (UDW) to more closely simulate over ground walking (OGW) during treadmill training. OGW involves a cyclic acceleration-deceleration profile of pelvic velocity that contrasts with typical treadmill-driven walking (TDW), which constrains a person to walk at a preset constant speed. In this study, we investigated the effects of the proposed speed adaptation controller by analyzing the gait kinematics of UDW and TDW, which were compared to those of OGW at three pre-determined velocities. Ten healthy subjects were asked to walk in each mode (TDW, UDW, and OGW) at three pre-determined speeds (0.5 m/s, 1.0 m/s, and 1.5 m/s) with real time feedback provided through visual displays. Temporal-spatial gait data and 3D pelvic kinematics were analyzed and comparisons were made between UDW on a treadmill, TDW, and OGW. The observed step length, cadence, and walk ratio defined as the ratio of stride length to cadence were not significantly different between UDW and TDW. Additionally, the average magnitude of pelvic acceleration peak values along the anterior-posterior direction for each step and the associated standard deviations (variability) were not significantly different between the two modalities. The differences between OGW and UDW and TDW were mainly in swing time and cadence, as have been reported previously. Also, step lengths between OGW and TDW were different for 0.5 m/s and 1.5 m/s gait velocities, and walk ratio between OGS and UDW was

  12. A novel walking speed estimation scheme and its application to treadmill control for gait rehabilitation

    Directory of Open Access Journals (Sweden)

    Yoon Jungwon

    2012-08-01

    Full Text Available Abstract Background Virtual reality (VR technology along with treadmill training (TT can effectively provide goal-oriented practice and promote improved motor learning in patients with neurological disorders. Moreover, the VR + TT scheme may enhance cognitive engagement for more effective gait rehabilitation and greater transfer to over ground walking. For this purpose, we developed an individualized treadmill controller with a novel speed estimation scheme using swing foot velocity, which can enable user-driven treadmill walking (UDW to more closely simulate over ground walking (OGW during treadmill training. OGW involves a cyclic acceleration-deceleration profile of pelvic velocity that contrasts with typical treadmill-driven walking (TDW, which constrains a person to walk at a preset constant speed. In this study, we investigated the effects of the proposed speed adaptation controller by analyzing the gait kinematics of UDW and TDW, which were compared to those of OGW at three pre-determined velocities. Methods Ten healthy subjects were asked to walk in each mode (TDW, UDW, and OGW at three pre-determined speeds (0.5 m/s, 1.0 m/s, and 1.5 m/s with real time feedback provided through visual displays. Temporal-spatial gait data and 3D pelvic kinematics were analyzed and comparisons were made between UDW on a treadmill, TDW, and OGW. Results The observed step length, cadence, and walk ratio defined as the ratio of stride length to cadence were not significantly different between UDW and TDW. Additionally, the average magnitude of pelvic acceleration peak values along the anterior-posterior direction for each step and the associated standard deviations (variability were not significantly different between the two modalities. The differences between OGW and UDW and TDW were mainly in swing time and cadence, as have been reported previously. Also, step lengths between OGW and TDW were different for 0.5 m/s and 1.5 m/s gait velocities

  13. Physiologic Responses to Motorized and Non-Motorized Locomotion Utilizing the International Space Station Treadmill

    Science.gov (United States)

    Smith, Cassie; Lee, Stuart MC; Laughlin, Mitzi; Loehr, James; Norcross, Jason; DeWitt, John; Hagan, R. D.

    2006-01-01

    Treadmill locomotion is used onboard the International Space Station (ISS) as a countermeasure to the effects of prolonged weightlessness. The treadmill operates in two modes: motorized (T-M) and non-motorized (T-NM). Little is known about the potential physiologic differences between modes which may affect countermeasure exercise prescription. PURPOSE: To quantify heart rate (HR), oxygen consumption (VO2), perceived exertion (RPE), and blood lactate (BLa) during T-M and T-NM locomotion at 2 and 4 mph in normal ambulatory subjects. METHODS: Twenty subjects (10 men, 10 women; 31+/-5 yr, 172+/-10 cm, 68+/-13 kg, mean SD) with a treadmill peakVO2 of 45.5+/-5.4 ml/kg/min (mean+/-SD) exercised on the ground-based ISS treadmill. Following a familiarization session in each mode, subjects completed two data collection sessions, T-M and T-NM in random order, at 2 and 4 mph. Subjects attempted to complete 5 min of exercise at each speed; if they could not maintain the speed, the trial was discontinued. At least 5 minutes of rest separated each speed trial, and at least 48 hrs separated each session. VO2 was measured continuously (metabolic gas analysis), while HR (HR monitor) and RPE (Borg Chart, 6-20 scale) were recorded each min. Not all subjects completed 5 min during each condition, therefore the mean of the min 3 and 4 was taken as representative of steady-state. BLa was measured (finger stick) within 2 min post-exercise. Paired t-tests were used to test for differences (p<0.05) between treadmill modes within the same speed. RESULTS: All twenty subjects completed at least 4 min of exercise during all conditions, except T-NM 4 mph when only 11 subjects completed the minimum exercise duration. VO2, HR, RPE and BLa were significantly higher during T-NM locomotion at both speeds.

  14. [Potential analysis for research on physiotherapy-led treadmill training in Parkinson's disease].

    Science.gov (United States)

    Lohkamp, Monika; Braun, Cordula; Wasner, Mieke; Voigt-Radloff, Sebastian

    2014-01-01

    Parkinson's disease is one of the major neurodegenerative disorders with prevalence rates between 0.1 and 0.2 % in the global population and 1.8 % in people aged 64 years and over. Future incidence rates are estimated to increase within aging societies. The progressive course of Parkinson's disease is clinically characterised by bradykinesia, rigidity and tremor. These limitations in motor functioning reduce the capacity to work, social participation and the clients' quality of life. Parkinson's disease causes incapacity to work and a large number of days off from work. The benefits clients expect from physiotherapy-led treatment include an improvement of gait, a better speed of motion and the decrease of fatigue and rigidity. A recent Cochrane review (Mehrholz et al., 2010) analysed seven randomised comparisons with 153 participants and found that treadmill training compared with no treatment improved gait speed (SMD 0.50; 95 % confidence interval [0.17 to 0.84]). A lack of evidence exists on how to reduce fatigue and rigidity. There is also need to evaluate long-term effects and cost-effectiveness. Furthermore, an updated meta-analysis should include eleven new randomised trials on treadmill training after 2009. Physiotherapy-led treadmill training can easily be transferred into the German healthcare context since the environmental and educational preconditions are met by German physiotherapeutic care. Within the German context, there is need to prepare a randomised clinical trial evaluating the impact of physiotherapy-led treadmill training on motor functioning, quality of life, costs, adverse events und long-term effects. Prior to this, a feasibility study should explore the acceptance and intensity of treadmill training as well as the access of private physiotherapy practices to people suffering from early- to mid-stage Parkinson's disease. Copyright © 2014. Published by Elsevier GmbH.

  15. Comparison of energy expenditure between aquatic and overground treadmill walking in people post-stroke.

    Science.gov (United States)

    Jung, Taeyou; Ozaki, Yoshi; Lai, Byron; Vrongistinos, Konstantinos

    2014-03-01

    This study aimed to compare the cardiorespiratory responses between aquatic treadmill walking (ATW) and overground treadmill walking (OTW) in people with hemiparesis post-stroke. Eight participants post-stroke aged 58.5 ± 11.4 years and eight healthy adult controls aged 56.1 ± 8.6 years participated in a cross-sectional comparative study. Participants completed three 8-minute walking sessions separated by at least 72-hour rest. On the first visit, participants identified their comfortable walking speed on an aquatic and overground treadmill. The second and third visit consisted of either ATW or OTW at a matched speed. Oxygen consumption (VO2), carbon dioxide production (VCO2 ), minute ventilation (VE) and energy expenditure (EE) were measured at rest and during walking in both exercise modes. Mean steady-state cardiorespiratory responses during ATW showed a significant decrease compared with OTW at a matched speed. During ATW, mean VO2 values decreased by 39% in the stroke group and 21% in the control group, mean VCO2 values decreased by 42% in the stroke group and 30% in the control group, and mean EE decreased by 40% in the stroke group and 25% in the control group. Mean steady-state VE values and resting cardiorespiratory response values showed no significant change between the two conditions. This study demonstrated a decreased metabolic cost when ATW at matched speeds to that of OTW. Reduced metabolic cost during ATW may allow for longer durations of treadmill-induced gait training compared with OTW for improved outcomes. This knowledge may aid clinicians when prescribing aquatic treadmill exercise for people post-stroke with goals of improving gait and functional mobility. However, decreased metabolic cost during ATW suggests that to improve cardiovascular fitness, ATW may not be a time-efficient method of cardiovascular exercise for healthy adults and people post-stroke. Copyright © 2013 John Wiley & Sons, Ltd.

  16. Differences in Lower Body Kinematics during Forward Treadmill Skating Between Two Different Hockey Skate Designs

    Directory of Open Access Journals (Sweden)

    Mike R. Hellyer

    2016-01-01

    Full Text Available Purpose: The purpose of this study was to investigate the differences in ankle flexibility and skating technique between a traditional hockey skate boot and a hockey skate boot with a flexible rear tendon guard. Skating technique was further investigated at different speeds to give insight on how skating technique alters as skating speed is increased. Methods: Eight elite hockey players were selected for the present study, which was conducted while skating on an Endless Ice Skating Treadmill.  Variables were recorded using a three-camera setup and measured from video records at five selected treadmill speeds using the Dartfish Team Pro v6 software.  Kinematic variables were then compared between the two skate designs with a doubly multivariate repeated measures design.  Statistical significance was set at p<0.05.  Results: Post hoc univariate tests comparing skate designs displayed significant increases in plantar flexion, plantar flexion angular velocity, hip extension, hip extension angular velocity, stride length, and stride velocity while participants were wearing the skates that had a flexible rear tendon guard.  Significant increases were also displayed in plantar flexion, plantar flexion angular velocity, knee extension, knee extension angular velocity, hip extension, hip extension angular velocity, hip abduction range of motion, hip abduction angular velocity, stride width, stride length, and stride velocity as the treadmill speed increased. There was also a significant decrease in the time the skate was in contact with the treadmill as treadmill speed increased. Conclusion: The results suggested that while skating forward, hockey players could improve their hockey skating technique by using hockey skates that have a flexible rear tendon guard.  This flexible tendon guard improved skating technique by increasing the time of force application to the ice by increasing the range of ankle plantar flexion during propulsion of the

  17. Negative Pressure Pulmonary Oedema Following Adenoidectomy ...

    African Journals Online (AJOL)

    threatening complication of laryngospasm that occurs during or after general anaesthesia. It is a complication of poorly treated or unrecognized laryngospasm occurring at extubation or later in the postoperative period. Objective: To emphasize ...

  18. NEGATIVE PRESSURE WOUND THERAPY (NPWT) FOR THE ...

    African Journals Online (AJOL)

    S. O. Khainga, MBChB, MMed (Nrb), FECSA (Plastic Surgery), Consultant Plastic and ... Associate Professor, Department of Surgery, College of Health Sciences, University .... abdomen secondary to acute pancreatitis. ... wall defect and enterocutaneous fistula treatment ... and chronic wounds: a randomized controlled trial.

  19. Post-exercise hypotensive responses following an acute bout of aquatic and overground treadmill walking in people post-stroke: a pilot study.

    Science.gov (United States)

    Lai, Byron; Jeng, Brenda; Vrongistinos, Konstantinos; Jung, Taeyou

    2015-06-01

    The purpose of this study is to investigate the effects of a single-bout of aquatic treadmill walking (ATW) and overground treadmill walking (OTW) on the magnitude and duration of post-exercise ambulatory blood pressure (BP) in people post-stroke. Seven people post-stroke participated in a cross-sectional comparative study. BP was monitored for up to 9 hours after a 15-minute bout of ATW and OTW at approximately 70% of maximal oxygen consumption (VO2max), performed on separate days. Mean systolic and diastolic BP values were compared between both exercise conditions and a day without exercise (control). Three hours after OTW, mean SBP increased by 9% from pre-exercise baseline compared to a 3% decrease during the control day (P stroke can sustain sufficient walking intensities necessary to reduce BP following cardiovascular exercise. Also, these data suggest that ATW can elicit clinically meaningful reductions in DBP and night-time SBP. Thus, it is recommended for clinicians to consider ATW as a non-pharmaceutical means to regulate DBP and promote nighttime dipping of SBP in people post-stroke. However, caution is advised during the immediate hours after exercise, a period of possible BP inflation.

  20. Joint kinematics and kinetics of overground accelerated running versus running on an accelerated treadmill.

    Science.gov (United States)

    Caekenberghe, Ine Van; Segers, Veerle; Aerts, Peter; Willems, Patrick; De Clercq, Dirk

    2013-07-06

    Literature shows that running on an accelerated motorized treadmill is mechanically different from accelerated running overground. Overground, the subject has to enlarge the net anterior-posterior force impulse proportional to acceleration in order to overcome linear whole body inertia, whereas on a treadmill, this force impulse remains zero, regardless of belt acceleration. Therefore, it can be expected that changes in kinematics and joint kinetics of the human body also are proportional to acceleration overground, whereas no changes according to belt acceleration are expected on a treadmill. This study documents kinematics and joint kinetics of accelerated running overground and running on an accelerated motorized treadmill belt for 10 young healthy subjects. When accelerating overground, ground reaction forces are characterized by less braking and more propulsion, generating a more forward-oriented ground reaction force vector and a more forwardly inclined body compared with steady-state running. This change in body orientation as such is partly responsible for the changed force direction. Besides this, more pronounced hip and knee flexion at initial contact, a larger hip extension velocity, smaller knee flexion velocity and smaller initial plantarflexion velocity are associated with less braking. A larger knee extension and plantarflexion velocity result in larger propulsion. Altogether, during stance, joint moments are not significantly influenced by acceleration overground. Therefore, we suggest that the overall behaviour of the musculoskeletal system (in terms of kinematics and joint moments) during acceleration at a certain speed remains essentially identical to steady-state running at the same speed, yet acting in a different orientation. However, because acceleration implies extra mechanical work to increase the running speed, muscular effort done (in terms of power output) must be larger. This is confirmed by larger joint power generation at the level of

  1. Treadmill Exercise with Increased Body Loading Enhances Post Flight Functional Performance

    Science.gov (United States)

    Bloomberg, J. J.; Batson, C. D.; Buxton, R. E.; Feiveson, A. H.; Kofman, I. S.; Laurie, S.; Lee, S. M. C.; Miller, C. A.; Mulavara, A. P.; Peters, B. T.; hide

    2014-01-01

    The goals of the Functional Task Test (FTT) study were to determine the effects of space flight on functional tests that are representative of high priority exploration mission tasks and to identify the key underlying physiological factors that contribute to decrements in performance. Ultimately this information will be used to assess performance risks and inform the design of countermeasures for exploration class missions. We have previously shown that for Shuttle, ISS and bed rest subjects functional tasks requiring a greater demand for dynamic control of postural equilibrium (i.e. fall recovery, seat egress/obstacle avoidance during walking, object translation, jump down) showed the greatest decrement in performance. Functional tests with reduced requirements for postural stability (i.e. hatch opening, ladder climb, manual manipulation of objects and tool use) showed little reduction in performance. These changes in functional performance were paralleled by similar decrements in sensorimotor tests designed to specifically assess postural equilibrium and dynamic gait control. The bed rest analog allows us to investigate the impact of axial body unloading in isolation on both functional tasks and on the underlying physiological factors that lead to decrements in performance and then compare them with the results obtained in our space flight study. These results indicate that body support unloading experienced during space flight plays a central role in postflight alteration of functional task performance. Given the importance of body-support loading we set out to determine if there is a relationship between the load experienced during inflight treadmill exercise (produced by a harness and bungee system) and postflight functional performance. ISS crewmembers (n=13) were tested using the FTT protocol before and after 6 months in space. Crewmembers were tested three times before flight, and on 1, 6, and 30 days after landing. To determine how differences in body

  2. Joint kinematics and kinetics of overground accelerated running versus running on an accelerated treadmill

    Science.gov (United States)

    Van Caekenberghe, Ine; Segers, Veerle; Aerts, Peter; Willems, Patrick; De Clercq, Dirk

    2013-01-01

    Literature shows that running on an accelerated motorized treadmill is mechanically different from accelerated running overground. Overground, the subject has to enlarge the net anterior–posterior force impulse proportional to acceleration in order to overcome linear whole body inertia, whereas on a treadmill, this force impulse remains zero, regardless of belt acceleration. Therefore, it can be expected that changes in kinematics and joint kinetics of the human body also are proportional to acceleration overground, whereas no changes according to belt acceleration are expected on a treadmill. This study documents kinematics and joint kinetics of accelerated running overground and running on an accelerated motorized treadmill belt for 10 young healthy subjects. When accelerating overground, ground reaction forces are characterized by less braking and more propulsion, generating a more forward-oriented ground reaction force vector and a more forwardly inclined body compared with steady-state running. This change in body orientation as such is partly responsible for the changed force direction. Besides this, more pronounced hip and knee flexion at initial contact, a larger hip extension velocity, smaller knee flexion velocity and smaller initial plantarflexion velocity are associated with less braking. A larger knee extension and plantarflexion velocity result in larger propulsion. Altogether, during stance, joint moments are not significantly influenced by acceleration overground. Therefore, we suggest that the overall behaviour of the musculoskeletal system (in terms of kinematics and joint moments) during acceleration at a certain speed remains essentially identical to steady-state running at the same speed, yet acting in a different orientation. However, because acceleration implies extra mechanical work to increase the running speed, muscular effort done (in terms of power output) must be larger. This is confirmed by larger joint power generation at the level

  3. Physiological responses of young thoroughbred horses to intermittent high-intensity treadmill training.

    Science.gov (United States)

    Ohmura, Hajime; Matsui, Akira; Hada, Tetsuro; Jones, James H

    2013-08-17

    Training of young Thoroughbred horses must balance development of cardiopulmonary function and aerobic capacity with loading of the musculoskeletal system that can potentially cause structural damage and/or lameness. High-speed equine treadmills are sometimes used to supplement exercise on a track in the training of young Thoroughbreds because the horse can run at high speeds but without the added weight of a rider. We tested the hypothesis that intermittent high-intensity exercise on a treadmill of young Thoroughbred horses entering training can enhance development of aerobic capacity (VO2max) and running performance more than conventional training under saddle, and do so without causing lameness. Twelve yearling Thoroughbreds trained for 8 months with conventional riding (C) only, conventional riding plus a short (2 month, S) interval of once-per-week high-intensity treadmill exercise, or a long (8 month, L) interval of once-per-week high-intensity treadmill exercise. Three treadmill exercise tests evaluated VO2max, oxygen transport and running performance variables in June of the yearling year (only for L), October of the yearling year and April of the 2-year-old year. No horses experienced lameness during the study. Aerobic capacity increased in all groups after training. In both October and April, VO2max in L was higher than in C, but did not differ between L and S or S and C. Running speeds eliciting VO2max also increased in all groups after training, with S (809±3 m/s) and L (804±9 m/s) higher than C (764±27 m/s). Maximum heart rate decreased for all groups after training. Hematocrit and hemoglobin concentration increased for L throughout training. Young Thoroughbred horses can increase aerobic capacity and running performance more than by strictly using track training under saddle with the addition of intermittent high-intensity treadmill exercise, and they can do so without experiencing lameness. This finding suggests that young racehorses might be able

  4. Treadmill training of infants with Down syndrome: evidence-based developmental outcomes.

    Science.gov (United States)

    Ulrich, D A; Ulrich, B D; Angulo-Kinzler, R M; Yun, J

    2001-11-01

    On average, infants with Down syndrome (DS) learn to walk about 1 year later than nondisabled (ND) infants. The purpose of this study was to determine if practice stepping on a motorized treadmill could help reduce the delay in walking onset normally experienced by these infants. Thirty families of infants with DS were randomly assigned to the intervention or control group. All infants were karyotyped trisomy 21 and began participation in the study when they could sit alone for 30 seconds (Bayley Scales of Infant Development, Second Edition 1993, item 34). Infants received traditional physical therapy at least every other week. In addition, intervention infants received practice stepping on a small, motorized treadmill, 5 days per week, for 8 minutes a day, in their own homes. Parents were trained to support their infants on these specially engineered miniature treadmills. Every 2 weeks research staff went into the homes and tested infants' overall motor progress by administering the Bayley Scales of Infant Development, Second Edition, monitored growth status via a battery of 11 anthropometric measures, and checked parents' compliance with physical therapy and treadmill intervention. The primary measures of the intervention's effectiveness were comparisons between the groups on the length of time elapsed between sitting for 30 seconds (entry into the study) and 1) raising self to stand; 2) walking with help; and 3) walking independently. The experimental group learned to walk with help and to walk independently significantly faster (73.8 days and 101 days, respectively) than the control group, both of which also produced large effect size statistics for the group differences. The groups were not statistically different for rate of learning to raise self to stand but there was a moderate effect size statistic suggesting that the groups were meaningfully different in favor of the experimental group. These results provide evidence that, with training and support

  5. Does treadmill running performance, heart rate and breathing rate response during maximal graded exercise improve after volitional respiratory muscle training?

    Science.gov (United States)

    Radhakrishnan, K; Sharma, V K; Subramanian, S K

    2017-05-10

    Maximal physical exertion in sports usually causes fatigue in the exercising muscles, but not in the respiratory muscles due to triggering of the Respiratory muscle metabo-reflex, a sympathetic vasoconstrictor response leading to preferential increment in blood flow to respiratory muscles. 1 We planned to investigate whether a six week yogic pranayama based Volitional Respiratory Muscle Training (VRMT) can improve maximal Graded Exercise Treadmill Test (GXTT) performance in healthy adult recreational sportspersons. Consecutive, consenting healthy adult recreational sportspersons aged 20.56±2.49 years (n=30), volunteered to 'baseline recording' of resting heart rate (HR), blood pressure (BP), respiratory rate (RR), and Bruce ramp protocol maximal GXTT until volitional exhaustion providing total test time (TTT), derived VO2max, Metabolic Equivalent of Task (METs), HR and BP response during maximal GXTT and drop in recovery HR data. After six weeks of observation, they underwent 'pre-intervention recording' followed by supervised VRMT intervention for 6 weeks (30 minutes a day; 5 days a week) and then 'post-intervention recording'. Repeated measures ANOVA with pairwise t statistical comparison was used to analyse the data. After supervised VRMT, we observed significant decrease in their resting supine RR (prespiratory muscle aerobic capacity, attenuation of respiratory muscle metabo-reflex, increase in cardiac stroke volume and autonomic resetting towards parasympatho-dominance. Yogic Pranayama based VRMT can be used in sports conditioning programme of athletes to further improve their maximal exercise performance, and as part of rehabilitation training during return from injury.

  6. Transient left ventricular apical ballooning and exercise induced hypertension during treadmill exercise testing: is there a common hypersympathetic mechanism?

    Directory of Open Access Journals (Sweden)

    Oh Jae K

    2008-07-01

    Full Text Available Abstract Objective To describe two cases of Takotsubo like myocardial contractile pattern during exercise stress test secondary to hypertensive response. Background Treadmill exercise testing is known to cause sympathetic stimulation, leading to increased levels of catecholamine, resulting in alteration in vascular tone. Hypertensive response during exercise testing can cause abnormal consequences, resulting in false positive results. Cases We present the cases of two patients experiencing apical and basal akinesis during exercise stress echocardiography, in whom normal wall motion response was observed on subsequent pharmacologic stress testing. The first patient developed transient left ventricular (LV apical akinesis during exercise stress echocardiography. Due to high suspicion that this abnormality might be secondary to hypertensive response, pharmacologic stress testing was performed after three days, which was completely normal and showed no such wall motion abnormality. Qualitative assessment of myocardial perfusion using contrast was also performed, which showed good myocardial blood flow, indicating low probability for significant obstructive coronary artery disease. The second patient developed LV basal akinesis as a result of hypertensive response during exercise testing. Coronary angiogram was not performed in either patient due to low suspicion for coronary artery disease, and subsequently negative stress studies. Results Transient stress induced cardiomyopathy can develop secondary to hypertensive response during exercise stress testing. Conclusion These cases provide supporting evidence to the hyper-sympathetic theory of left ventricular ballooning syndrome.

  7. Multistage treadmill exercise testing with a multiple unipolar precordial lead system in the evaluation of effort angina pectoris

    International Nuclear Information System (INIS)

    Shiki, Kazuhito; Tsuzuki, Masato; Kawai, Naoki; Kondo, Teruo; Sotobata, Iwao

    1984-01-01

    Sixty-one patients who had angina pectoris without prior myocardial infarction and 24 healthy men were studied by multistage treadmill exercise testing with 20 unipolar leads covering the left anterolateral hemithorax. Exercise-induced ST- segment changes were compared with the results of stress thallium-201 myocardial images and also with coronary arteriographic fingings. All patients had more than 75% narrowing of at least one major coronary artery. Fifty-one of the 61 patients had diagnostically significant exercise-induced ischemic ST-segment depression (sensitivity 83.6%) and all of the 24 controls showed a negative exercise test (specificity 100%). The exercise-induced ST-segment depressions appeared most often in the area just below V 5 . The number of leads with ST-segment depression and the sum of the depths of ST-segment depressions significantly correlated with the number of regions-of-interest of stress-induced hypoperfusion of myocardial scintigraphy (r = 0.62 and r = 0.61, respectively). These parameters increased as the number of diseased coronary arteries increased, but were not influenced by the presence or absence of coronary collateral circulation. The maximum depth of ST-segment depression was greater in triple vessel disease than in single or double vessel disease (p 5 . (J.P.N.)

  8. Analysis Spectrum of ECG Signal and QRS Detection during Running on Treadmill

    Science.gov (United States)

    Agung Suhendra, M.; Ilham R., M.; Simbolon, Artha I.; Faizal A., M.; Munandar, A.

    2018-03-01

    The heart is an important organ in our metabolism in which it controls circulatory and oxygen. The heart exercise is needed one of them using the treadmill to prevent health. To analysis, it using electrocardiograph (ECG) to investigating and diagnosing anomalies of the heart. In this paper, we would like to analysis ECG signals during running on the treadmill with kinds of speeds. There are two analysis ECG signals i.e. QRS detection and power spectrum density (PSD). The result of PSD showed that subject 3 has highly for all subject and the result of QRS detection using pan Tomkins algorithm that a percentage of failed detection is an approaching to 0 % for all subject.

  9. Treadmill training as an augmentation treatment for Alzheimer?s disease: a pilot randomized controlled study

    Directory of Open Access Journals (Sweden)

    Cynthia Arcoverde

    2014-03-01

    Full Text Available Objective To assess the effect of aerobic exercise on the cognition and functional capacity in Alzheimer’s disease (AD patients. Method Elderly (n=20 with mild dementia (NINCDS-ADRDA/CDR1 were randomly assigned to an exercise group (EG on a treadmill (30 minutes, twice a week and moderate intensity of 60% VO2max and control group (GC 10 patients. The primary outcome measure was the cognitive function using Cambridge Cognitive Examination (CAMCOG. Specifics instruments were also applied to evaluate executive function, memory, attention and concentration, cognitive flexibility, inhibitory control and functional capacity. Results After 16 weeks, the EG showed improvement in cognition CAMCOG whereas the CG declined. Compared to the CG, the EG presented significant improvement on the functional capacity. The analysis of the effect size has shown a favorable response to the physical exercise in all dependent variables. Conclusion Walking on treadmill may be recommended as an augmentation treatment for patients with AD.

  10. Efficacy of Aquatic Treadmill Training on Gait Symmetry and Balance in Subacute Stroke Patients.

    Science.gov (United States)

    Lee, Mi Eun; Jo, Geun Yeol; Do, Hwan Kwon; Choi, Hee Eun; Kim, Woo Jin

    2017-06-01

    To determine the efficacy of aquatic treadmill training (ATT) as a new modality for stroke rehabilitation, by assessing changes in gait symmetry, balance function, and subjective balance confidence for the paretic and non-paretic leg in stroke patients. Twenty-one subacute stroke patients participated in 15 intervention sessions of aquatic treadmill training. The Comfortable 10-Meter Walk Test (CWT), spatiotemporal gait parameters, Berg Balance Scale (BBS), and Activities-specific Balance Confidence scale (ABC) were assessed pre- and post-interventions. From pre- to post-intervention, statistically significant improvements were observed in the CWT (0.471±0.21 to 0.558±0.23, pstroke therapy, with other modalities.

  11. Evaluation of a Treadmill with Vibration Isolation and Stabilization (TVIS) for Use on the International Space Station

    Science.gov (United States)

    McCrory, Jean L.; Lemmon, David R.; Sommer, H. Joseph; Prout, Brian; Smith, Damon; Korth, Deborah W.; Lucero, Javier; Greenisen, Michael; Moore, Jim

    1999-01-01

    A treadmill with vibration isolation and stabilization designed for the International Space Station (ISS) was evaluated during Shuttle mission STS-81. Three crew members ran and walked on the device, which floats freely in zero gravity. For the majority of the more than 2 hours of locomotion studied, the treadmill showed peak to peak linear and angular displacements of less than 2.5 cm and 2.5 deg, respectively. Vibration transmitted to the vehicle was within the microgravity allocation limits that are defined for the ISS. Refinements to the treadmill and harness system are discussed. This approach to treadmill design offers the possibility of generating 1G-like loads on the lower extremities while preserving the microgravity environment of the ISS for structural safety and vibration free experimental conditions.

  12. Optimal spectral tracking - with application to speed dependent neural modulation of tibialis anterior during human treadmill walking

    DEFF Research Database (Denmark)

    Brittain, John-Stuart; Catton, Celia; Conway, Bernard A.

    2009-01-01

    ) during healthy treadmill locomotion. The approach adopts adaptive filter theory while retaining a spectral focus, thus remaining compatible with much of the current literature. Spectral tracking procedures are evaluated using both surrogate and neurophysiological time-series. Confidence intervals...

  13. Role of adenosine in the regulation of coronary blood flow in swine at rest and during treadmill exercise

    NARCIS (Netherlands)

    D.J.G.M. Duncker (Dirk); R. Stubenitsky (René); P.D. Verdouw (Pieter)

    1998-01-01

    textabstractA pivotal role for adenosine in the regulation of coronary blood flow is still controversial. Consequently, we investigated its role in the regulation of coronary vasomotor tone in swine at rest and during graded treadmill exercise. During exercise,

  14. Fractal fluctuations in spatiotemporal variables when walking on a self-paced treadmill.

    Science.gov (United States)

    Choi, Jin-Seung; Kang, Dong-Won; Seo, Jeong-Woo; Tack, Gye-Rae

    2017-12-08

    This study investigated the fractal dynamic properties of stride time (ST), stride length (SL) and stride speed (SS) during walking on a self-paced treadmill (STM) in which the belt speed is automatically controlled by the walking speed. Twelve healthy young subjects participated in the study. The subjects walked at their preferred walking speed under four conditions: STM, STM with a metronome (STM+met), fixed-speed (conventional) treadmill (FTM), and FTM with a metronome (FTM+met). To compare the fractal dynamics between conditions, the mean, variability, and fractal dynamics of ST, SL, and SS were compared. Moreover, the relationship among the variables was examined under each walking condition using three types of surrogates. The mean values of all variables did not differ between the two treadmills, and the variability of all variables was generally larger for STM than for FTM. The use of a metronome resulted in a decrease in variability in ST and SS for all conditions. The fractal dynamic characteristics of SS were maintained with STM, in contrast to FTM, and only the fractal dynamic characteristics of ST disappeared when using a metronome. In addition, the fractal dynamic patterns of the cross-correlated surrogate results were identical to those of all variables for the two treadmills. In terms of the fractal dynamic properties, STM walking was generally closer to overground walking than FTM walking. Although further research is needed, the present results will be useful in research on gait fractal dynamics and rehabilitation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Peptidoglycan synthesis drives an FtsZ-treadmilling-independent step of cytokinesis.

    Science.gov (United States)

    Monteiro, João M; Pereira, Ana R; Reichmann, Nathalie T; Saraiva, Bruno M; Fernandes, Pedro B; Veiga, Helena; Tavares, Andreia C; Santos, Margarida; Ferreira, Maria T; Macário, Vânia; VanNieuwenhze, Michael S; Filipe, Sérgio R; Pinho, Mariana G

    2018-02-22

    Peptidoglycan is the main component of the bacterial wall and protects cells from the mechanical stress that results from high intracellular turgor. Peptidoglycan biosynthesis is very similar in all bacteria; bacterial shapes are therefore mainly determined by the spatial and temporal regulation of peptidoglycan synthesis rather than by the chemical composition of peptidoglycan. The form of rod-shaped bacteria, such as Bacillus subtilis or Escherichia coli, is generated by the action of two peptidoglycan synthesis machineries that act at the septum and at the lateral wall in processes coordinated by the cytoskeletal proteins FtsZ and MreB, respectively. The tubulin homologue FtsZ is the first protein recruited to the division site, where it assembles in filaments-forming the Z ring-that undergo treadmilling and recruit later divisome proteins. The rate of treadmilling in B. subtilis controls the rates of both peptidoglycan synthesis and cell division. The actin homologue MreB forms discrete patches that move circumferentially around the cell in tracks perpendicular to the long axis of the cell, and organize the insertion of new cell wall during elongation. Cocci such as Staphylococcus aureus possess only one type of peptidoglycan synthesis machinery, which is diverted from the cell periphery to the septum in preparation for division. The molecular cue that coordinates this transition has remained elusive. Here we investigate the localization of S. aureus peptidoglycan biosynthesis proteins and show that the recruitment of the putative lipid II flippase MurJ to the septum, by the DivIB-DivIC-FtsL complex, drives peptidoglycan incorporation to the midcell. MurJ recruitment corresponds to a turning point in cytokinesis, which is slow and dependent on FtsZ treadmilling before MurJ arrival but becomes faster and independent of FtsZ treadmilling after peptidoglycan synthesis activity is directed to the septum, where it provides additional force for cell envelope

  16. The Effects of Combined Treadmill Training and Pharmacological Treatment on Management of Multiple Sclerosis Female Patients

    Directory of Open Access Journals (Sweden)

    Ali Asghar Arastoo

    2013-04-01

    Full Text Available Objectives: To compare the effectiveness of two treatment methods of ‘combination pharmacological treatment and treadmill training’ and ‘pharmacological treatment’ on management of multiple sclerosis (MS female patients. Methods: In this quasi experimental and interventional study a sample of 20 MS patients (mean age: 36.75 years with Expanded Disability Status Scale scores (EDSS 1.0 to 4.0 were randomly assigned to a ‘pharmacologic treatment’ (Ph group and a combination group of ‘pharmacologic treatment& treadmill training’ (PhTT. All these individuals used the drugs of choice ‘Rebif’ and ‘Avonex’. The intervention consisted of 8-weeks (24 sessions of treadmill training (30 minutes each, at 40-75% of age-predicted maximum heart rate for the PhTT group. The Ph group followed their own routine treatment program. Balance, speed and endurance of walking, quality of life and fatigue were measured by Berg Balance Score, 10 meter timed walk test, 2 minute walk test, and Fatigue Severity Scale (FFS. Data were analyzed by paired t test and one way ANOVA. Results: Comparison of results indicated that pre and post intervention led to significant improvements in the balance score (P=0.001, 10m walk time (P=0.001, walking endurance (P=0.007, and FFS (P=0.04 in the PhTT group. In contrast, no significant changes were observed in the Ph group’s balance score, 10m timed walk and fatigue, while there was a significant decrease in the 2min walking distance (P=0.015 in this group. Discussion: These results suggest that treadmill training in combination with pharmacological treatment improve balance and walking capacity and level of fatigue in women with mild to moderate MS.

  17. Treadmill Exercise Attenuates Retinal Oxidative Stress in Naturally-Aged Mice: An Immunohistochemical Study

    Directory of Open Access Journals (Sweden)

    Chan-Sik Kim

    2015-09-01

    Full Text Available In the retina, a number of degenerative diseases, including glaucoma, diabetic retinopathy, and age-related macular degeneration, may occur as a result of aging. Oxidative damage is believed to contribute to the pathogenesis of aging as well as to age-related retinal disease. Although physiological exercise has been shown to reduce oxidative stress in rats and mice, it is not known whether it has a similar effect in retinal tissues. The aim of this study was to evaluate retinal oxidative stress in naturally-aged mice. In addition, we evaluated the effects of aerobic training on retinal oxidative stress by immunohistochemically evaluating oxidative stress markers. A group of twelve-week-old male mice were not exercised (young control. Two groups of twenty-two-month-old male mice were created: an old control group and a treadmill exercise group. The old control group mice were not exercised. The treadmill exercise group mice ran on a treadmill (5 to 12 m/min, 30 to 60 min/day, 3 days/week for 12 weeks. The retinal thickness and number of cells in the ganglion cell layer of the naturally-aged mice were reduced compared to those in the young control mice. However, treadmill exercise reversed these morphological changes in the retinas. We evaluated retinal expression of carboxymethyllysine (CML, 8-hydroxy-2′-deoxyguanosine (8-OHdG and nitrotyrosine. The retinas from the aged mice showed increased CML, 8-OHdG, and nitrotyrosine immunostaining intensities compared to young control mice. The exercise group exhibited significantly lower CML levels and nitro-oxidative stress than the old control group. These results suggest that regular exercise can reduce retinal oxidative stress and that physiological exercise may be distinctly advantageous in reducing retinal oxidative stress.

  18. Changes in muscle activation patterns in response to enhanced sensory input during treadmill stepping in infants born with myelomeningocele

    OpenAIRE

    Pantall, Annette; Teulier, Caroline; Ulrich, Beverly D.

    2012-01-01

    Infants with myelomeningocele (MMC) increase step frequency in response to modifications to the treadmill surface. The aim was to investigate how these modifications impacted the electromyographic (EMG) patterns. We analyzed EMG from 19 infants aged 2–10 months, with MMC at the lumbosacral level. We supported infants upright on the treadmill for 12 trials, each 30 seconds long. Modifications included visual flow, unloading, weights, Velcro and lcriction. Surface electrodes recorded EMG from t...

  19. External Mechanical Work and Pendular Energy Transduction of Overground and Treadmill Walking in Adolescents with Unilateral Cerebral Palsy

    OpenAIRE

    Zollinger, Marie; Degache, Francis; Currat, Gabriel; Pochon, Ludmila; Peyrot, Nicolas; Newman, Christopher J.; Malatesta, Davide

    2016-01-01

    PURPOSE: Motor impairments affect functional abilities and gait in children and adolescents with cerebral palsy (CP). Improving their walking is an essential objective of treatment, and the use of a treadmill for gait analysis and training could offer several advantages in adolescents with CP. However, there is a controversy regarding the similarity between treadmill and overground walking both for gait analysis and training in children and adolescents. The aim of this study was to compare th...

  20. Cost analysis of negative-pressure wound therapy with instillation for wound bed preparation preceding split-thickness skin grafts for massive (>100 cm(2)) chronic venous leg ulcers.

    Science.gov (United States)

    Yang, C Kevin; Alcantara, Sean; Goss, Selena; Lantis, John C

    2015-04-01

    Massive (≥100 cm(2)) venous leg ulcers (VLUs) demonstrate very low closure rates with standard compression therapy and are costly to manage. Negative-pressure wound therapy (NPWT), followed by a split-thickness skin graft (STSG), can be a cost-effective alternative to this standard care. We performed a cost analysis of these two treatments. A retrospective review was performed of 10 ulcers treated with surgical debridement, 7 days of inpatient NPWT with topical antiseptic instillation (NPWTi), and STSG, with 4 additional days of inpatient NPWT bolster over the graft. Independent medical cost estimators were used to compare the cost of this treatment protocol with standard outpatient compression therapy. The average length of time ulcers were present before patients entered the study was 38 months (range, 3-120 months). Eight of 10 patients had complete VLU closure by 6 months after NPWTi with STSG. The 6-month costs of the proposed treatment protocol and standard twice-weekly compression therapy were estimated to be $27,000 and $28,000, respectively. NPWTi with STSG treatment is more effective for closure of massive VLUs at 6 months than that reported for standard compression therapy. Further, the cost of the proposed treatment protocol is comparable with standard compression therapy. Copyright © 2015 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

  1. Loading Configurations and Ground Reaction Forces During Treadmill Running in Weightlessness

    Science.gov (United States)

    DeWitt, John; Schaffner, Grant; Blazine, Kristi; Bentley, Jason; Laughlin, Mitzi; Loehr, James; Hagan, Donald

    2003-01-01

    Studies have shown losses in bone mineral density of 1-2% per month in critical weight bearing areas such as the proximal femur during long-term space flight (Grigoriev, 1998). The astronauts currently onboard the International Space Station (ISS) use a treadmill as an exercise countermeasure to bone loss that occurs as a result of prolonged exposure to weightlessness. A crewmember exercising on the treadmill is attached by a harness and loading device. Ground reaction forces are obtained through the loading device that pulls the crewn1ember towards the treadmill surface during locomotion. McCrory et al. (2002) found that the magnitude of the peak ground reaction force (pGRF) during horizontal suspension running, or simulated weightlessness, was directly related to the load applied to the subject. It is thought that strain magnitude and strain rate affects osteogenesis, and is a function of the magnitude and rate of change of the ground reaction force. While it is not known if a minimum stimulus exists for osteogenesis, it has been hypothesized that in order to replicate the bone formation occurring in normal gravity (1 G), the exercise in weightlessness should mimic the forces that occur on earth. Specifically, the pGRF obtained in weightlessness should be comparable to that achieved in 1 G.

  2. The influence of water depth on kinematic and spatiotemporal gait parameters during aquatic treadmill walking.

    Science.gov (United States)

    Jung, Taeyou; Kim, Yumi; Lim, Hyosok; Vrongistinos, Konstantinos

    2018-01-16

    The purpose of this study was to investigate kinematic and spatiotemporal variables of aquatic treadmill walking at three different water depths. A total of 15 healthy individuals completed three two-minute walking trials at three different water depths. The aquatic treadmill walking was conducted at waist-depth, chest-depth and neck-depth, while a customised 3-D underwater motion analysis system captured their walking. Each participant's self-selected walking speed at the waist level was used as a reference speed, which was applied to the remaining two test conditions. A repeated measures ANOVA showed statistically significant differences among the three walking conditions in stride length, cadence, peak hip extension, hip range of motion (ROM), peak ankle plantar flexion and ankle ROM (All p values hip ROM as the water depth rose from waist and chest to the neck level. However, our study found no significant difference between waist and chest level water in all variables. Hydrodynamics, such as buoyancy and drag force, in response to changes in water depths, can affect gait patterns during aquatic treadmill walking.

  3. Antigravity treadmill training during the early rehabilitation phase following unicompartmental knee arthroplasty: A case series.

    Science.gov (United States)

    Huang, Chun-Hao; Schroeder, E Todd; Powers, Christopher

    2018-02-26

    Patients who have undergone unicompartmental knee arthroplasty (UKA) have been reported to exhibit altered gait 19-25 months post-surgery. The most common gait impairment in this population is inadequate knee flexion and a corresponding decrease in the knee extensor moment during loading response (i.e., quadriceps avoidance). The purpose of this case series was to determine whether incorporation of antigravity treadmill training into a standard physical therapy program can eliminate quadriceps avoidance gait during the early rehabilitation phase following UKA. Four females who underwent UKA were recruited for this study. Participants completed antigravity treadmill training three times per week for 12 weeks in addition to their standard physical therapy program. Instrumented gait analysis was performed at baseline (pre-intervention), week 6 (mid-intervention), and week 12 (post-intervention). We found that peak knee flexion and the peak knee extensor moment during the weight acceptance phase of gait increased to normal values following the 12-week intervention period (14.1 ± 6.5° to 20.6 ± 1.5° and 0.4 ± 0.3 to 0.7 ± 0.2 Nm/kg respectively). The findings of this case series suggest that a standard physical therapy program that incorporates early gait training using an antigravity treadmill may be beneficial in eliminating "quadriceps avoidance" during the early rehabilitation phase following UKA.

  4. Influence of treadmill acceleration on actual walk-to-run transition.

    Science.gov (United States)

    Van Caekenberghe, I; Segers, V; De Smet, K; Aerts, P; De Clercq, D

    2010-01-01

    When accelerating continuously, humans spontaneously change from a walking to a running pattern by means of a walk-to-run transition (WRT). Results of previous studies indicate that when higher treadmill accelerations are imposed, higher WRT-speeds can be expected. By studying the kinematics of the WRT at different accelerations, the underlying mechanisms can be unravelled. 19 young, healthy female subjects performed walk-to-run transitions on a constantly accelerating treadmill (0.1, 0.2 and 0.5 m s(-2)). A higher acceleration induced a higher WRT-speed, by effecting the preparation of transition, as well as the actual transition step. Increasing the acceleration caused a higher WRT-speed as a result of a greater step length during the transition step, which was mainly a consequence of a prolonged airborne phase. Besides this effect on the transition step, the direct preparation phase of transition (i.e. the last walking step before transition) appeared to fulfil specific constraints required to execute the transition regardless of the acceleration imposed. This highlights an important role for this step in the debate regarding possible determinants of WRT. In addition spatiotemporal and kinematical data confirmed that WRT remains a discontinuous change of gait pattern in all accelerations imposed. It is concluded that the walk-to-run transition is a discontinuous switch from walking to running which depends on the magnitude of treadmill belt acceleration. Copyright 2009 Elsevier B.V. All rights reserved.

  5. Different Intensities of Treadmill Running Exercise do Not Alter Melatonin Levels in Rats

    Directory of Open Access Journals (Sweden)

    Ionara Rodrigues Siqueira

    2011-04-01

    Full Text Available Background: Regular and moderate exercise has been considered an interesting neuroprotective strategy. Our research group demonstrated that a protocol of moderate exercise on a treadmill reduced, while a protocol of high-intensity exercise increased in vitro ischemic cell damage in Wistar rats. The molecular mechanisms by which physical exercise exerts neuroprotective effects remain unclear. Accumulating evidence suggests that exercise may have short- and long-term effects on melatonin secretion in humans. Melatonin, the main product of the pineal gland, has been shown to have neuroprotective effects in models of brain and spinal cord injury and cerebral ischemia. A dual modulation of melatonin secretion by physical activity has also been demonstrated. This study aimed to investigate the effect of different exercise intensities, moderate- and high-intensity exercise, on serum melatonin levels in rats. Methods: Thirty-five adult male Wistar rats were divided into non-exercised (sedentary and exercised (20- or 60-min sessions groups. The exercise protocols consisted of two weeks of daily treadmill training. Blood samples were collected approximately 16 hours after the last training session (8:00-10:00 and melatonin levels were assayed by ELISA. Results: The exercise protocols, two weeks of 20 min/day or 60 min/day of treadmill running, did not affect serum melatonin levels. Conclusion: Our data demonstrated that melatonin levels may not be directly involved in the exercise-induced, intensity-dependent dual effect on in vitro ischemia.

  6. Matching optical flow to motor speed in virtual reality while running on a treadmill

    Science.gov (United States)

    Lafortuna, Claudio L.; Mugellini, Elena; Abou Khaled, Omar

    2018-01-01

    We investigated how visual and kinaesthetic/efferent information is integrated for speed perception in running. Twelve moderately trained to trained subjects ran on a treadmill at three different speeds (8, 10, 12 km/h) in front of a moving virtual scene. They were asked to match the visual speed of the scene to their running speed–i.e., treadmill’s speed. For each trial, participants indicated whether the scene was moving slower or faster than they were running. Visual speed was adjusted according to their response using a staircase until the Point of Subjective Equality (PSE) was reached, i.e., until visual and running speed were perceived as equivalent. For all three running speeds, participants systematically underestimated the visual speed relative to their actual running speed. Indeed, the speed of the visual scene had to exceed the actual running speed in order to be perceived as equivalent to the treadmill speed. The underestimation of visual speed was speed-dependent, and percentage of underestimation relative to running speed ranged from 15% at 8km/h to 31% at 12km/h. We suggest that this fact should be taken into consideration to improve the design of attractive treadmill-mediated virtual environments enhancing engagement into physical activity for healthier lifestyles and disease prevention and care. PMID:29641564

  7. Evaluation of a workplace treadmill desk intervention: a randomized controlled trial.

    Science.gov (United States)

    Schuna, John M; Swift, Damon L; Hendrick, Chelsea A; Duet, Megan T; Johnson, William D; Martin, Corby K; Church, Timothy S; Tudor-Locke, Catrine

    2014-12-01

    To evaluate the effectiveness of a 3-month treadmill desk intervention in eliciting changes in physical activity and sedentary behavior among overweight/obese office workers. A randomized controlled trial was conducted among overweight/obese office workers (n = 41; mean age = 40.1 ± 10.1 years) at a private workplace. Participants were randomly assigned to a shared-treadmill desk intervention (n = 21) or a usual working condition control group (n = 20). Accelerometer-determined physical activity and sedentary behavior were measured before and after the intervention. Compared with the control group, the intervention group increased daily steps (1622 steps/day; P = 0.013) and light physical activity (1.6 minutes/hour; P = 0.008), and decreased sedentary time (-3.6 minutes/hour; P = 0.047) during working hours. Shared-treadmill desks in the workplace can be effective at promoting favorable changes in light physical activity (specifically 40 to 99 steps/minute) and sedentary behavior among overweight/obese office workers.

  8. Habituation of 10-year-old hockey players to treadmill skating.

    Science.gov (United States)

    Lockwood, Kelly L; Frost, Gail

    2007-05-01

    This study assessed changes in selected physiological and kinematic variables over 6 weeks of treadmill skating in an effort to understand the process of habituation to this novel training modality. Seven male, Atom-A hockey players who were injury-free and had no previous treadmill skating experience participated in the study. Players performed four 1-min skating bouts at progressively increasing speeds, each week, for 6 weeks. One speed (10.5 km/h) was repeated weekly to allow for assessment of the habituation process. Our criteria for habituation were: a decrease in stride rate, heart rate and rating of perceived exertion, and an increase in stride length, trunk angle and vertical movement of the centre of mass, leading to a plateau, over the course of the 6-week study. Significant decreases were seen in stride rate, heart rate and ratings of perceived exertion, and significant increases were found in stride length. Some of these changes were evident after only one week of training and all were present by week 4. After 6 weeks (24 min) of exposure to treadmill skating, all participants displayed a visibly more efficient skating style.

  9. A physiological and biomechanical comparison of over-ground, treadmill and ergometer wheelchair propulsion.

    Science.gov (United States)

    Mason, Barry; Lenton, John; Leicht, Christof; Goosey-Tolfrey, Victoria

    2014-01-01

    The purpose of the study was to determine which laboratory-based modality provides the most valid physiological and biomechanical representation of over-ground sports wheelchair propulsion. Fifteen able-bodied participants with previous experience of wheelchair propulsion performed a 3-minute exercise trial at three speeds (4, 6 and 8 km ∙ h(-1)) in three testing modalities over separate sessions: (i) over-ground propulsion on a wooden sprung surface; (ii) wheelchair ergometer propulsion; (iii) treadmill propulsion at four different gradients (0%, 0.7%, 1.0% and 1,3%). A 0.7% treadmill gradient was shown to best reflect the oxygen uptake (7.3 to 9.1% coefficient of variation (CV)) and heart rate responses (4.9 to 6.4% CV) of over-ground propulsion at 4 and 6 km ∙ h(-1). A 1.0% treadmill gradient provided a more valid representation of oxygen uptake during over-ground propulsion at 8 km ∙ h(-1) (8.6% CV). Physiological demand was significantly underestimated in the 0% gradient and overestimated in the 1.3% gradient and wheelchair ergometer trials compared to over-ground trials (Ppropulsion at lower speeds (4 and 6 km ∙ h(-1)) whereas a 1.0% gradient may be more suitable at 8 km ∙ h(-1).

  10. Generalization of improved step length symmetry from treadmill to overground walking in persons with stroke and hemiparesis†

    Science.gov (United States)

    Savin, Douglas N.; Morton, Susanne M.; Whitall, Jill

    2013-01-01

    Objectives Determine whether adaptation to a swing phase perturbation during gait transferred from treadmill to overground walking, the rate of overground deadaptation, and whether overground aftereffects improved step length asymmetry in persons with hemiparetic stroke and gait asymmetry. Methods Ten participants with stroke and hemiparesis and 10 controls walked overground on an instrumented gait mat, adapted gait to a swing phase perturbation on a treadmill, then walked overground on the gait mat again. Outcome measures, primary: overground step length symmetry, rates of treadmill step length symmetry adaptation and overground step length symmetry deadaptation; secondary: overground gait velocity, stride length, and stride cycle duration. Results Step length symmetry aftereffects generalized to overground walking and adapted at a similar rate on the treadmill in both groups. Aftereffects decayed at a slower rate overground in participants with stroke and temporarily improved overground step length asymmetry. Both groups’ overground gait velocity increased post adaptation due to increased stride length and decreased stride duration. Conclusions Stroke and hemiparesis do not impair generalization of step length symmetry changes from adapted treadmill to overground walking, but prolong overground aftereffects. Significance Motor adaptation during treadmill walking may be an effective treatment for improving overground gait asymmetries post-stroke. PMID:24286858

  11. Duration-dependence of the effect of treadmill exercise on hyperactivity in attention deficit hyperactivity disorder rats.

    Science.gov (United States)

    Ji, Eun-Sang; Kim, Chang-Ju; Park, Jun Heon; Bahn, Geon Ho

    2014-04-01

    Attention-deficit hyperactivity disorder (ADHD) is a common neurobehavioral disorder, and its symptoms are hyperactivity and deficits in learning and memory. Physical exercise increases dopamine synthesis and neuronal activity in various brain regions. In the present study, we investigate the duration-dependence of the treadmill exercise on hyperactivity in relation with dopamine expression in ADHD. Spontaneously hypertensive rats were used for the ADHD rats and Wistar-Kyoto rats were used for the control rats. The rats in the exercise groups were forced to run on a treadmill for 10 min, 30 min, and 60 min once daily for 28 consecutive days. For this experiment, open field test and immunohistochemistry for tyrosine hydroxylase were conducted. The present results revealed that ADHD rats showed hyperactivity, and tyrosine hydroxylase expression in the striatum and substantia nigra were decreased in ADHD rats. Treadmill exercise alleviated hyperactivity and also increased TH expression in ADHD rats. Treadmill exercise for 30 min per day showed most potent suppressing effect on hyperactivity, and this dose of treadmill exercise also most potently inhibited tyrosine hydroxylase expression. The present study suggests that treadmill exercise for 30 min once a day is the most effective therapeutic intervention for ADHD patients.

  12. Pre-Ischemic Treadmill Training for Prevention of Ischemic Brain Injury via Regulation of Glutamate and Its Transporter GLT-1

    Directory of Open Access Journals (Sweden)

    Jingchun Guo

    2012-07-01

    Full Text Available Pre-ischemic treadmill training exerts cerebral protection in the prevention of cerebral ischemia by alleviating neurotoxicity induced by excessive glutamate release following ischemic stroke. However, the underlying mechanism of this process remains unclear. Cerebral ischemia-reperfusion injury was observed in a rat model after 2 weeks of pre-ischemic treadmill training. Cerebrospinal fluid was collected using the microdialysis sampling method, and the concentration of glutamate was determined every 40 min from the beginning of ischemia to 4 h after reperfusion with high-performance liquid chromatography (HPLC-fluorescence detection. At 3, 12, 24, and 48 h after ischemia, the expression of the glutamate transporter-1 (GLT-1 protein in brain tissues was determined by Western blot respectively. The effect of pre-ischemic treadmill training on glutamate concentration and GLT-1 expression after cerebral ischemia in rats along with changes in neurobehavioral score and cerebral infarct volume after 24 h ischemia yields critical information necessary to understand the protection mechanism exhibited by pre-ischemic treadmill training. The results demonstrated that pre-ischemic treadmill training up-regulates GLT-1 expression, decreases extracellular glutamate concentration, reduces cerebral infarct volume, and improves neurobehavioral score. Pre-ischemic treadmill training is likely to induce neuroprotection after cerebral ischemia by regulating GLT-1 expression, which results in re-uptake of excessive glutamate.

  13. Recovery of heart rate variability after treadmill exercise analyzed by lagged Poincaré plot and spectral characteristics.

    Science.gov (United States)

    Shi, Ping; Hu, Sijung; Yu, Hongliu

    2018-02-01

    The aim of this study was to analyze the recovery of heart rate variability (HRV) after treadmill exercise and to investigate the autonomic nervous system response after exercise. Frequency domain indices, i.e., LF(ms 2 ), HF(ms 2 ), LF(n.u.), HF(n.u.) and LF/HF, and lagged Poincaré plot width (SD1 m ) and length (SD2 m ) were introduced for comparison between the baseline period (Pre-E) before treadmill running and two periods after treadmill running (Post-E1 and Post-E2). The correlations between lagged Poincaré plot indices and frequency domain indices were applied to reveal the long-range correlation between linear and nonlinear indices during the recovery of HRV. The results suggested entirely attenuated autonomic nervous activity to the heart following the treadmill exercise. After the treadmill running, the sympathetic nerves achieved dominance and the parasympathetic activity was suppressed, which lasted for more than 4 min. The correlation coefficients between lagged Poincaré plot indices and spectral power indices could separate not only Pre-E and two sessions after the treadmill running, but also the two sessions in recovery periods, i.e., Post-E1 and Post-E2. Lagged Poincaré plot as an innovative nonlinear method showed a better performance over linear frequency domain analysis and conventional nonlinear Poincaré plot.

  14. Attention demanding tasks during treadmill walking reduce step width variability in young adults

    Directory of Open Access Journals (Sweden)

    Troy Karen L

    2005-08-01

    Full Text Available Abstract Background The variability of step time and step width is associated with falls by older adults. Further, step time is significantly influenced when performing attention demanding tasks while walking. Without exception, step time variability has been reported to increase in normal and pathologically aging older adults. Because of the role of step width in managing frontal plane dynamic stability, documenting the influence of attention-demanding tasks on step width variability may provide insight to events that can disturb dynamic stability during locomotion and increase fall risk. Preliminary evidence suggests performance of an attention demanding task significantly decreases step width variability of young adults walking on a treadmill. The purpose of the present study was to confirm or refute this finding by characterizing the extent and direction of the effects of a widely used attention demanding task (Stroop test on the step width variability of young adults walking on a motorized treadmill. Methods Fifteen healthy young adults walked on a motorized treadmill at a self-selected velocity for 10 minutes under two conditions; without performing an attention demanding task and while performing the Stroop test. Step width of continuous and consecutive steps during the collection was derived from the data recorded using a motion capture system. Step width variability was computed as the standard deviation of all recorded steps. Results Step width decreased four percent during performance of the Stroop test but the effect was not significant (p = 0.10. In contrast, the 16 percent decrease in step width variability during the Stroop test condition was significant (p = 0.029. Conclusion The results support those of our previous work in which a different attention demanding task also decreased step width variability of young subjects while walking on a treadmill. The decreased step width variability observed while performing an attention

  15. Pressure induced insulator–metal transition and giant negative piezoresistance in Pr{sub 0.6}Ca{sub 0.4}Mn{sub 0.96}Al{sub 0.04}O{sub 3} polycrystal

    Energy Technology Data Exchange (ETDEWEB)

    Arumugam, S., E-mail: sarumugam1963@yahoo.com [Centre for High Pressure Research, School of Physics, Bharathidasan University, Tiruchirapalli 620024, Tamil Nadu (India); Thiyagarajan, R. [Center for High Pressure Science and Technology Advanced Research (HPSTAR), Shanghai 201203 (China); Kalaiselvan, G.; Sivaprakash, P. [Centre for High Pressure Research, School of Physics, Bharathidasan University, Tiruchirapalli 620024, Tamil Nadu (India)

    2016-11-01

    The effect of external hydrostatic pressure (P) on the magnetization (M) and resistivity (ρ) properties of charge-orbital (CO) ordered-insulating phase-separated manganite Pr{sub 0.6}Ca{sub 0.4}Mn{sub 0.96}Al{sub 0.04}O{sub 3} system is reported here. At ambient P, CO ordering transition and spin-canting in the AFM are observed at 223 K and 55 K respectively in M(T) and ρ(T) measurements. Application of P increases simultaneously the magnitude of magnetization (M) and transition temperature, and weakens the CO ordering in M(T) measurements up to 0.98 GPa. During ρ(T) measurements, P induces an insulator–metallic transition (T{sub IM}) at 1.02 GPa, and further increase of P up to 2.84 GPa leads to increase of T{sub IM} (dT{sub IM}/dP =21.6 K/GPa). ρ at T{sub IM} is reduced about three orders of magnitude at 2.84 GPa, and leads to the giant negative piezoresistance (~98%). These results are analyzed separately in two temperature regions i.e., below and above T{sub IM} by power function equation and small polaronic hopping model respectively. It is understood from these analyses that the application of P suppresses the Jahn–Teller distortions, electron–electron and electron–magnon scattering factors, and induces the insulator–metal transition in Pr{sub 0.6}Ca{sub 0.4}Mn{sub 0.96}Al{sub 0.04}O{sub 3} system. - Highlights: • Application of P on Pr{sub 0.6}Ca{sub 0.4}Mn{sub 0.96}Al{sub 0.04}O{sub 3} reduces resistivity (ρ) remarkably at low-temperatures, and exhibits an insulator to metallic transition at 1.02 GPa. • The reduction in ρ by P is about three orders of magnitude at 2.84 GPa, leads to the giant negative piezoresistance about 98%. • The effect of the suppression of Jahn–Teller distortions, electron–electron and electron–magnon scattering under an applied P exhibits to the metal-Insulator transition. • The phase-separation in this system has been tuned by both internal and external perturbations.

  16. Effect of Negative Pressure Wound Therapy vs Standard Wound Management on 12-Month Disability Among Adults With Severe Open Fracture of the Lower Limb: The WOLLF Randomized Clinical Trial.

    Science.gov (United States)

    Costa, Matthew L; Achten, Juul; Bruce, Julie; Tutton, Elizabeth; Petrou, Stavros; Lamb, Sarah E; Parsons, Nick R

    2018-06-12

    Open fractures of the lower limb occur when a broken bone penetrates the skin. There can be major complications from these fractures, which can be life-changing. To assess the disability, rate of deep infection, and quality of life in patients with severe open fracture of the lower limb treated with negative pressure wound therapy (NPWT) vs standard wound management after the first surgical debridement of the wound. Multicenter randomized trial performed in the UK Major Trauma Network, recruiting 460 patients aged 16 years or older with a severe open fracture of the lower limb from July 2012 through December 2015. Final outcome data were collected through November 2016. Exclusions were presentation more than 72 hours after injury and inability to complete questionnaires. NPWT (n = 226) in which an open-cell solid foam or gauze was placed over the surface of the wound and connected to a suction pump, creating a partial vacuum over the dressing, vs standard dressings not involving application of negative pressure (n = 234). Disability Rating Index score (range, 0 [no disability] to 100 [completely disabled]) at 12 months was the primary outcome measure, with a minimal clinically important difference of 8 points. Secondary outcomes were complications including deep infection and quality of life (score ranged from 1 [best possible] to -0.59 [worst possible]; minimal clinically important difference, 0.08) collected at 3, 6, 9, and 12 months. Among 460 patients who were randomized (mean age, 45.3 years; 74% men), 88% (374/427) of available study participants completed the trial. There were no statistically significant differences in the patients' Disability Rating Index score at 12 months (mean score, 45.5 in the NPWT group vs 42.4 in the standard dressing group; mean difference, -3.9 [95% CI, -8.9 to 1.2]; P = .13), in the number of deep surgical site infections (16 [7.1%] in the NPWT group vs 19 [8.1%] in the standard dressing group; difference, 1.0% [95

  17. Modelamiento del Ambiente Térmico y Aéreo de un Galpón de Presión Negativa Tipo Túnel para Pollitos / Modeling of the Thermal Environments in Shed Negative Pressure Tunnel Type of Chicks

    Directory of Open Access Journals (Sweden)

    Robinson Osorio Hernández

    2013-12-01

    Full Text Available La optimización de los procesos productivos tiene granimportancia en el mundo actual debido al continuo desarrollo y avance. Con la finalidad de evaluar el desempeño productivo en el sector avícola, se hace necesaria la adecuación del ambiente interno de las instalaciones avícolas con técnicas que atiendan las exigencias de confort térmico con mayor eficiencia energética. En este trabajo, se evaluó el ambiente térmico interno de un galpón de presión negativa tipo túnel durante la primera fase de crecimiento de pollos de engorde. La evaluación de comportamiento térmico en este período fue realizada utilizando la dinámica de fluidos computacionales (CFD. El modelo computacional demostró ser una herramienta eficaz para el entendimiento y mejora de diseños bioclimáticos de ambientes internos de galpones avícolas. / The optimization of production processes hasgreat importance in the world due to the development andadvancement. In order to evaluate the productive performance in poultry production, it becomes necessary the indoor environmental adequacy of the poultry buildings by technologies that attend the requirements of thermal comfort with major energy efficiency. This study evaluated the thermal environment of a domestic shed of negative pressure tunnel type, during the first growth phase of broilers. The evaluation of the thermal behavior model during this period was made using the computational fluid dynamics (CFD. The computational model proved to be an effective tool forunderstanding and improving of bioclimatic designs of indoorenvironments to create this kind of sheds.

  18. Treadmill exercise alleviates stress-induced impairment of social interaction through 5-hydroxytryptamine 1A receptor activation in rats.

    Science.gov (United States)

    Kim, Tae-Woon; Lim, Baek-Vin; Kim, Kijeong; Seo, Jin-Hee; Kim, Chang-Ju

    2015-08-01

    Brain-derived neurotrophic factor (BDNF) and its receptors tyrosine kinase B (trkB), and cyclic adenosine monophosphate response element binding protein (CREB) have been suggested as the neurobiological risk factors causing depressive disorder. Serotonin (5-hydroxytryptamine, 5-HT) plays an important role in the pathogenesis of depression. We in-vestigated the effect of treadmill exercise on social interaction in relation with BDNF and 5-HT expressions following stress in rats. Stress was induced by applying inescapable 0.2 mA electric foot shock to the rats for 7 days. The rats in the exercise groups were forced to run on a motorized treadmill for 30 min once a day for 4 weeks. Social interaction test and western blot for BDNF, TrkB, pCREB, and 5-HT1A in the hippocampus were performed. The results indicate that the spend time with unfamiliar partner was decreased by stress, in contrast, treadmill exercise increased the spending time in the stress-induced rats. Expressions of BDNF, TrkB, and pCREB were decreased by stress, in contrast, treadmill exercise enhanced expressions of BDNF, TrkB, and pCREB in the stress-induced rats. In addition, 5-HT1A receptor expression was de-creased by stress, in contrast, treadmill exercise enhanced 5-HT1A expression in the stress-induced rats. In the present study, treadmill exercise alleviated stress-induced social interaction impairment through enhancing hippocampal plasticity and serotonergic function in the hippocampus. These effects of treadmill exercise are achieved through 5-HT1A receptor activation.