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Sample records for cerebral tissue oxygenation

  1. Cerebral Tissue Oxygenation during Immediate Neonatal Transition and Resuscitation

    Science.gov (United States)

    Pichler, Gerhard; Schmölzer, Georg M.; Urlesberger, Berndt

    2017-01-01

    This article provides a review of cerebral tissue oxygenation during immediate transition after birth in human neonates. Recommended routine monitoring, especially if resuscitation is needed, during this period includes arterial oxygen saturation and heart rate measured by pulse oximetry and electrocardiogram. However, there is increasing interest to monitor in addition with near-infrared spectroscopy (NIRS) the oxygenation of the brain. There is a different pattern of increase between cerebral tissue oxygenation and arterial oxygen saturation during the immediate transition, with cerebral tissue oxygenation reaching a plateau faster than arterial oxygen saturation. Differences can be explained, since cerebral tissue oxygenation is not only affected by arterial oxygen saturation but also by cerebral blood flow, hemoglobin content, and cerebral oxygen consumption. Normal values have already been established for different devices, gestational ages, and modes of delivery in neonates without any medical support. Cerebral hypoxia during immediate transition might cause brain damage. In preterm neonates with cerebral hemorrhage evolving in the first week after birth, the cerebral tissue oxygenation is already lower in the first minutes after birth compared to preterm neonates without cerebral hemorrhage. Using cerebral NIRS in combination with intervention guidelines has been shown to reduce the burden of cerebral hypoxia in preterm neonates. Cerebral tissue oxygenation during immediate transition seems to have an impact on outcome, whereby NIRS monitoring is feasible and has the advantage of continuous, non-invasive recording. The impact of NIRS monitoring and interventions on short- and long-term outcomes still need to be evaluated. PMID:28280719

  2. Prognostic value of cerebral tissue oxygen saturation during neonatal extracorporeal membrane oxygenation

    Science.gov (United States)

    Clair, Marie-Philippine; Rambaud, Jérôme; Flahault, Adrien; Guedj, Romain; Guilbert, Julia; Guellec, Isabelle; Durandy, Amélie; Demoulin, Maryne; Jean, Sandrine; Mitanchez, Delphine; Chalard, François; Sileo, Chiara; Carbajal, Ricardo; Renolleau, Sylvain

    2017-01-01

    Objectives Extracorporeal membrane oxygenation support is indicated in severe and refractory respiratory or circulatory failures. Neurological complications are typically represented by acute ischemic or hemorrhagic lesions, which induce higher morbidity and mortality. The primary goal of this study was to assess the prognostic value of cerebral tissue oxygen saturation (StcO2) on mortality in neonates and young infants treated with ECMO. A secondary objective was to evaluate the association between StcO2 and the occurrence of cerebral lesions. Study design This was a prospective study in infants < 3 months of age admitted to a pediatric intensive care unit and requiring ECMO support. Measurements The assessment of cerebral perfusion was made by continuous StcO2 monitoring using near-infrared spectroscopy (NIRS) sensors placed on the two temporo-parietal regions. Neurological lesions were identified by MRI or transfontanellar echography. Results Thirty-four infants <3 months of age were included in the study over a period of 18 months. The ECMO duration was 10±7 days. The survival rate was 50% (17/34 patients), and the proportion of brain injuries was 20% (7/34 patients). The mean StcO2 during ECMO in the non-survivors was reduced in both hemispheres (p = 0.0008 right, p = 0.03 left) compared to the survivors. StcO2 was also reduced in deceased or brain-injured patients compared to the survivors without brain injury (p = 0.002). Conclusion StcO2 appears to be a strong prognostic factor of survival and of the presence of cerebral lesions in young infants during ECMO. PMID:28278259

  3. Precision of measurement of cerebral tissue oxygenation index using near-infrared spectroscopy in preterm neonates

    DEFF Research Database (Denmark)

    Sorensen, Line C; Greisen, Gorm

    2006-01-01

    The use of cerebral tissue oxygenation index (c-TOI) in a clinical setting is limited by doubts concerning the accuracy of the measurements. Since there is no gold standard, validation is difficult. Our modest aim was to quantify the precision of c-TOI doing repeated measurements by reapplying th...

  4. Monitoring Cerebral Oxygenation in Neonates: An Update

    Science.gov (United States)

    Dix, Laura Marie Louise; van Bel, Frank; Lemmers, Petra Maria Anna

    2017-01-01

    Cerebral oxygenation is not always reflected by systemic arterial oxygenation. Therefore, regional cerebral oxygen saturation (rScO2) monitoring with near-infrared spectroscopy (NIRS) is of added value in neonatal intensive care. rScO2 represents oxygen supply to the brain, while cerebral fractional tissue oxygen extraction, which is the ratio between rScO2 and systemic arterial oxygen saturation, reflects cerebral oxygen utilization. The balance between oxygen supply and utilization provides insight in neonatal cerebral (patho-)physiology. This review highlights the potential and limitations of cerebral oxygenation monitoring with NIRS in the neonatal intensive care unit. PMID:28352624

  5. Correlation of brain tissue oxygen tension with cerebral near-infrared spectroscopy and mixed venous oxygen saturation during extracorporeal membrane oxygenation.

    Science.gov (United States)

    Tyree, Kreangkai; Tyree, Melissa; DiGeronimo, Robert

    2009-09-01

    The aim of this prospective, animal study was to compare brain tissue oxygen tension (PbtO(2)) with cerebral near infrared spectroscopy (NIRS) and mixed venous oxygen saturation (SVO(2)) during venoarterial extracorporeal membrane oxygenation (VA ECMO) in a porcine model. This was accomplished using twelve immature piglets with surgically implanted catheters placed in the superficial cerebral cortex to measure brain PbtO(2) and microdialysis metabolites. The NIRS sensor was placed overlying the forehead to measure cerebral regional saturation index (rSO(2)i) while SVO(2) was measured directly from the ECMO circuit. Animals were placed on VA ECMO followed by an initial period of stabilization, after which they were subjected to graded hypoxia and recovery. Our results revealed that rSO(2)i and SVO(2) correlated only marginally with PbtO(2) (R(2)=0.32 and R(2)=0.26, respectively) while the correlation between rSO(2)i and SVO( 2) was significantly stronger (R(2)=0.59). Cerebral metabolites and rSO(2)i were significantly altered during attenuation of PbtO( 2), p<0.05). A subset of animals, following exposure to hypoxia, experienced markedly delayed recovery of both rSO(2)i and PbtO( 2) despite rapid normalization of SVO(2). Upon further analysis, these animals had significantly lower blood pressure (p=0.001), lower serum pH (p=0.01), and higher serum lactate (p=0.02). Additionally, in this subgroup, rSO(2)i correlated better with PbtO(2) (R(2)=0.76). These findings suggest that, in our ECMO model, rSO(2)i and SVO( 2) correlate reasonably well with each other, but not necessarily with brain PbtO(2) and that NIRS-derived rSO(2)i may more accurately reflect cerebral tissue hypoxia in sicker animals.

  6. Real-time changes in brain tissue oxygen during endovascular treatment of cerebral vasospasm

    DEFF Research Database (Denmark)

    Rasmussen, Rune; Bache, Søren; Stavngaard, Trine

    2015-01-01

    minute-by-minute changes in brain tissue oxygen during balloon angioplasty and intraarterial administration of vasodilators in three patients.Our results confirm that endovascular intervention is capable of not only resolving angiographic vasospasm, but also of normalizing values of brain tissue oxygen...

  7. Transient hyperoxia does not affect regional cerebral tissue oxygen saturation in moderately preterm or term newborns

    DEFF Research Database (Denmark)

    Thing, Mira; Sørensen, Line Carøe; Pryds, Ole

    2015-01-01

    oxygen saturation (rStO2 ) and to evaluate whether any observed prolonged cerebral vasoconstriction was related to maturity. METHODS: The study included 30 infants with a postmenstrual age of more than 32 weeks, who were treated with nasal continuous positive airway pressure and a fraction of inspired......, with a mean difference of 1.37% (95% CI 0.15, 2.6). After the second oxygen exposure, rStO2 remained unchanged with a mean difference of -0.4% (95% CI -1.6, 0.78). Differences in rStO2 were not related to gestational age in either of the two hyperoxic episodes. CONCLUSION: We found no evidence to support...... the theory that transient hyperoxia induces prolonged cerebral vasoconstriction in infants with a postmenstrual age above 32 weeks....

  8. Effects of acetazolamide on cerebral blood flow and brain tissue oxygenation

    DEFF Research Database (Denmark)

    Lassen, N A; Friberg, L; Kastrup, J

    1987-01-01

    Oral administration of 1 g of acetazolamide to 8 normal subjects studied at sea level and in normoxia caused an acute increase in cerebral blood flow (CBF). During the subsequent prolonged oral treatment with 1 g of acetazolamide daily, CBF returned to normal within 2 days. The alveolar CO2 tension...... decreased gradually to 70% of the control value, indicating hyperventilation. At sea level hyperventilation will not increase brain oxygenation significantly in normal man, as the arterial oxygen content only increases minimally, while CBF is unchanged. At high altitude the beneficial effects...... of acetazolamide on the symptoms of acute mountain sickness may well be due to an improved oxygen supply to the brain, as hyperventilation will, at the low ambient PO2, cause a significant increase of the arterial oxygen content, while CBF presumably is unaffected by the drug. During hypoxia at high altitude...

  9. Initial clinical experience with near-infrared spectroscopy in assessing cerebral tissue oxygen saturation in cerebral vasospasm before and after intra-arterial verapamil injection.

    Science.gov (United States)

    Meng, Lingzhong; Settecase, Fabio; Xiao, Jifang; Yu, Zhaoxia; Flexman, Alana M; Higashida, Randall T

    2016-04-01

    Cerebral vasospasm is a devastating complication after subarachnoid hemorrhage. The use of cerebral tissue oxygen saturation (SctO2) to non-invasively assess changes in cerebral tissue perfusion induced by intra-arterial (IA) verapamil treatment has not been described to our knowledge. A total of 21 consecutive post-craniotomy patients scheduled for possible IA verapamil treatment of cerebral vasospasm were recruited. The effect of IA verapamil injection on SctO2 being continuously monitored on both the left and right forehead was investigated. Comparisons between changes in SctO2 monitored on the ipsilateral and contralateral forehead in relationship to the side of internal carotid artery (ICA) injection were performed. A total of 47 IA verapamil injections (15 left ICA, 18 right ICA, and 14 vertebral artery injections) during 18 neurointerventional procedures in 13 patients were analyzed. IA verapamil administration led to both increases and decreases in SctO2. Changes in SctO2 ipsilateral to the ICA injection side were more pronounced (p=0.02 and 0.07 for left and right ICA injections, respectively) and favored compared to contralateral SctO2 changes. We were unable to obtain reliable measurements on the side ipsilateral to the craniotomy during four procedures in three patients, presumably secondary to pneumocephalus. The local cerebral vasodilating effect of IA verapamil injection is suggested by the differential changes in SctO2 ipsilateral and contralateral to the ICA injection side. The inconsistent changes in SctO2 and the limitations of applying cerebral oximetry in this patient population needs to be recognized.

  10. Cerebral tissue oxygenation index and superior vena cava blood flow in the very low birth weight infant.

    LENUS (Irish Health Repository)

    Moran, M

    2012-02-01

    BACKGROUND: Superior vena cava (SVC) flow assesses blood flow from the upper body, including the brain. Near infrared spectroscopy (NIRS) provides information on brain perfusion and oxygenation. AIM: To assess the relationship between cerebral tissue oxygenation index (cTOI) and cardiac output measures in the very low birth weight (VLBW) infant in the first day of life. METHODS: A prospective observational cohort study. Neonates with birth weight less than 1500 g (VLBW) were eligible for enrollment. Newborns with congenital heart disease, major congenital malformations and greater than Papile grade1 Intraventricular Haemorrhage on day 1 of life were excluded. Echocardiographic evaluation of SVC flow was performed in the first 24 h of life. Low SVC flow states were defined as a flow less than 40 mL\\/kg\\/min. cTOI was measured using NIRO 200 Hamamatsu. RESULTS: Twenty-seven VLBW neonates had both echocardiography and NIRS performed. The median (range) gestation was 29\\/40 (25 + 3 to 31 + 5 weeks) and median birth weight was 1.2 kg (0.57-1.48 kg). The mean (SD) TOI was 68.1 (7.9)%. The mean (SD) SVC flow was 70.36(39.5) mLs\\/kg\\/min. The correlation coefficient of cerebral tissue oxygenation and SVC flow was r = 0.53, p-value 0.005. There was a poor correlation between right and left ventricular output and cTOI which is not surprising considering the influence of intra- and extracardiac shunts. CONCLUSION: There is a positive relationship between cerebral TOI values and SVC flow in the very low birth infant on day one of life.

  11. Cerebral oxygenation and hyperthermia

    Directory of Open Access Journals (Sweden)

    Anthony Richard Bain

    2014-03-01

    Full Text Available Hyperthermia is associated with marked reductions in cerebral blood flow (CBF. Increased distribution of cardiac output to the periphery, increases in alveolar ventilation and resultant hypocapnia each contribute to the fall in CBF during passive hyperthermia; however, their relative contribution remains a point of contention, and probably depends on the experimental condition (e.g. posture and degree of hyperthermia. The hyperthermia-induced hyperventilatory response reduces arterial CO2 pressure (PaCO2 causing cerebral vasoconstriction and subsequent reductions in flow. During supine passive hyperthermia, the majority of recent data indicate that reductions in PaCO2 may be the primary, if not sole, culprit for reduced CBF. On the other hand, during more dynamic conditions (e.g. hemorrhage or orthostatic challenges, an inability to appropriately decrease peripheral vascular conductance presents a condition whereby adequate cerebral perfusion pressure may be compromised secondary to reductions in systemic blood pressure. Although studies have reported maintenance of pre-frontal cortex oxygenation (assessed by near-infrared spectroscopy during exercise and severe heat stress, the influence of cutaneous blood flow is known to contaminate this measure. This review discusses the governing mechanisms associated with changes in CBF and oxygenation during moderate to severe (i.e. 1.0°C to 2.0°C increase in body core temperature levels of hyperthermia. Future research directions are provided.

  12. The SafeBoosC Phase II Randomised Clinical Trial : A Treatment Guideline for Targeted Near-Infrared-Derived Cerebral Tissue Oxygenation versus Standard Treatment in Extremely Preterm Infants

    NARCIS (Netherlands)

    Pellicer, Adelina; Greisen, Gorm; Benders, Manon; Claris, Olivier; Dempsey, Eugene; Fumagalli, Monica; Gluud, Christian; Hagmann, Cornelia; Hellstroem-Westas, Lena; Hyttel-Sorensen, Simon; Lemmers, Petra; Naulaers, Gunnar; Pichler, Gerhard; Roll, Claudia; van Bel, Frank; van Oeveren, Wim; Skoog, Maria; Wolf, Martin; Austin, Topun

    2013-01-01

    Near-infrared spectroscopy-derived regional tissue oxygen saturation of haemoglobin (rSto(2)) reflects venous oxygen saturation. If cerebral metabolism is stable, rSto(2) can be used as an estimate of cerebral oxygen delivery. The SafeBoosC phase II randomised clinical trial hypothesises that the bu

  13. Improvement of oxygen supply by an artificial carrier in combination with normobaric oxygenation decreases the volume of tissue hypoxia and tissue damage from transient focal cerebral ischemia

    NARCIS (Netherlands)

    Seiffge, David J.; Lapina, Natalia E.; Tsagogiorgas, Charalambos; Theisinger, Bastian; Henning, Robert H.; Schilling, Lothar

    2012-01-01

    Tissue hypoxia may play an important role in the development of ischemic brain damage. In the present study we investigated in a rat model of transient focal brain ischemia the neuroprotective effects of increasing the blood oxygen transport capacity by applying a semifluorinated alkane (SFA)-contai

  14. The effects of different ventilator modes on cerebral tissue oxygen saturation in patients with bidirectional superior cavopulmonary connection

    Directory of Open Access Journals (Sweden)

    Ayda Türköz

    2014-01-01

    Full Text Available Aims and Objectives: We used near-infrared spectroscopy to document changes in cerebral tissue oxygen saturation (SctO 2 in response to ventilation mode alterations after bidirectional Glenn (BDG; superior cavopulmonary connection procedure. We also determined whether spontaneous ventilation have a beneficial effect on hemodynamic status, lactate and SctO 2 when compared with other ventilation modes. Materials and Methods: 20 consecutive patients undergoing BDG were included. We measured SctO 2 during three ventilator modes (intermittent positive-pressure ventilation [IPPV]; synchronized intermittent mandatory ventilation [SIMV]; and continuous positive airway pressure + pressure support ventilation [CPAP + PSV]. We, also, measured mean airway pressure (AWP, arterial blood gases, lactate and systolic arterial pressures (SAP. Results: There was no change in SctO 2 in IPPV and SIMV modes; the SctO 2 measured during CPAP + PSV and after extubation increased significantly (60.5 ± 11, 61 ± 10, 65 ± 10, 66 ± 11 respectively ( P < 0.05. The differences in the SAP measured during IPPV and SIMV modes was insignificant; the SAP increased significantly during CPAP + PSV mode and after extubation compared with IPPV and SIMV (109 ± 11, 110 ± 12, 95 ± 17, 99 ± 13 mmHg, respectively ( P < 0.05. Mean AWP did not change during IPPV and SIMV modes, mean AWP decreased significantly during CPAP + PSV mode (14 ± 4, 14 ± 3, 10 ± 1 mmHg, respectively ( P < 0.01. Conclusions: The SctO 2 was higher during CPAP + PSV ventilation and after extubation compared to IPPV and SIMV modes of ventilation. The mean AWP was lower during CPAP + PSV ventilation compared to IPPV and SIMV modes of ventilation.

  15. Measuring tissue oxygenation

    Science.gov (United States)

    Soyemi, Olusola O. (Inventor); Soller, Babs R. (Inventor); Yang, Ye (Inventor)

    2009-01-01

    Methods and systems for calculating tissue oxygenation, e.g., oxygen saturation, in a target tissue are disclosed. In some embodiments, the methods include: (a) directing incident radiation to a target tissue and determining reflectance spectra of the target tissue by measuring intensities of reflected radiation from the target tissue at a plurality of radiation wavelengths; (b) correcting the measured intensities of the reflectance spectra to reduce contributions thereto from skin and fat layers through which the incident radiation propagates; (c) determining oxygen saturation in the target tissue based on the corrected reflectance spectra; and (d) outputting the determined value of oxygen saturation.

  16. Prenatal tobacco exposure influences cerebral oxygenation in preterm infants

    NARCIS (Netherlands)

    Verhagen, Elise A.; ter Horst, Hendrik J.; Kooi, Elisabeth M. W.; Keating, Paul; van den Berg, Paul P.; Bos, Arend F.

    2011-01-01

    Aim: Our aim was to determine the influence of prenatal tobacco exposure on regional cerebral tissue oxygen saturation (r(c)SO(2)) and fractional tissue oxygen extraction (FTOE) in preterm infants. We hypothesized that as a result of vasoconstriction caused by prenatal tobacco exposure r(c)SO(2) wou

  17. Cerebral oxygen delivery and consumption during evoked neural activity

    Directory of Open Access Journals (Sweden)

    Alberto L Vazquez

    2010-06-01

    Full Text Available Increases in neural activity evoke increases in the delivery and consumption of oxygen. Beyond observations of cerebral tissue and blood oxygen, the role and properties of cerebral oxygen delivery and consumption during changes in brain function are not well understood. This work overviews the current knowledge of functional oxygen delivery and consumption and introduces recent and preliminary findings to explore the mechanisms by which oxygen is delivered to tissue as well as the temporal dynamics of oxygen metabolism. Vascular oxygen tension measurements have shown that a relatively large amount of oxygen exits pial arterioles prior to capillaries. Additionally, increases in cerebral blood flow (CBF induced by evoked neural activation are accompanied by arterial vasodilation and also by increases in arteriolar oxygenation. This increase contributes not only to the down-stream delivery of oxygen to tissue, but also to delivery of additional oxygen to extra-vascular spaces surrounding the arterioles. On the other hand, the changes in tissue oxygen tension due to functional increases in oxygen consumption have been investigated using a method to suppress the evoked CBF response. The functional decreases in tissue oxygen tension induced by increases in oxygen consumption are slow to evoked changes in CBF under control conditions. Preliminary findings obtained using flavoprotein autofluorescence imaging suggest cellular oxidative metabolism changes at a faster rate than the average changes in tissue oxygen. These issues are important in the determination of the dynamic changes in tissue oxygen metabolism from hemoglobin-based imaging techniques such as blood oxygenation-level dependent functional magnetic resonance imaging (fMRI.

  18. Feasibility of mapping the tissue mass corrected bioscale of cerebral metabolic rate of oxygen consumption using 17-oxygen and 23-sodium MR imaging in a human brain at 9.4 T.

    Science.gov (United States)

    Atkinson, Ian C; Thulborn, Keith R

    2010-06-01

    The reduction of molecular oxygen to water is the final step of oxidative phosphorylation that couples adenosine triphosphate production to the reoxidation of reducing equivalents formed during the oxidation of glucose to carbon dioxide. This coupling makes the cerebral metabolic rate of oxygen consumption (CMRO(2)) an excellent reflection of the metabolic health of the brain. A multi-nuclear magnetic resonance (MR) imaging based method for CMRO(2) mapping is proposed. Oxygen consumption is determined by applying a new three-phase metabolic model for water generation and clearance to the changing 17-oxygen ((17)O) labeled water MR signal measured using quantitative (17)O MR imaging during inhalation of (17)O-enriched oxygen gas. These CMRO(2) data are corrected for the regional brain tissue mass computed from quantitative 23-sodium MR imaging of endogenous tissue sodium ions to derive quantitative results of oxygen consumption in micromoles O(2)/g tissue/minute that agree with literature results reported from positron emission tomography. The proposed technique is demonstrated in the human brain using a 9.4 T MR scanner optimized for human brain imaging.

  19. Neonatal cerebral oxygenation is not linked to foetal vasculitis and predicts intraventricular haemorrhage in preterm infants

    DEFF Research Database (Denmark)

    Sorensen, Line C; Maroun, Lisa L; Borch, Klaus;

    2008-01-01

    Aim: The aim of the study was to compare the cerebral tissue oxygenation index (c-TOI) measured by near infrared spectroscopy (NIRS) in infants with and without foetal vasculitis. Methods: Twenty-four infants with placental signs of a foetal inflammatory response (FIR), foetal vasculitis, were.......002). Conclusion: Cerebral oxygenation was not affected in the first day of life in preterm infants born with foetal vasculitis, while cerebral oxygenation in infants that later developed intraventricular haemorrhage was impaired....

  20. Neonatal cerebral oxygenation is not linked to foetal vasculitis and predicts intraventricular haemorrhage in preterm infants

    DEFF Research Database (Denmark)

    Sørensen, Line Carøe; Maroun, Lisa Leth; Borch, K.;

    2008-01-01

    AIM: The aim of the study was to compare the cerebral tissue oxygenation index (c-TOI) measured by near infrared spectroscopy (NIRS) in infants with and without foetal vasculitis. METHODS: Twenty-four infants with placental signs of a foetal inflammatory response (FIR), foetal vasculitis, were.......002). CONCLUSION: Cerebral oxygenation was not affected in the first day of life in preterm infants born with foetal vasculitis, while cerebral oxygenation in infants that later developed intraventricular haemorrhage was impaired Udgivelsesdato: 2008/11...

  1. Effect of balloon atrial septostomy on cerebral oxygenation in neonates with transposition of the great arteries

    NARCIS (Netherlands)

    van der Laan, Michelle E.; Verhagen, Elise A.; Bos, Arend F.; Berger, Rolf M. F.; Kooi, Elisabeth M. W.

    2013-01-01

    BACKGROUND: The aim of this study was to determine the effect of balloon atrial septostomy (BAS) on cerebral oxygenation in neonates with transposition of the great arteries (TGA). METHODS: In term neonates with TGA, regional cerebral tissue oxygen saturation (r(c)SO(2)) was measured using, near-inf

  2. Comparison of cerebral tissue oxygenation values in full term and preterm newborns by the simultaneous use of two near-infrared spectroscopy devices: an absolute and a relative trending oximeter

    Science.gov (United States)

    Szczapa, Tomasz; Karpiński, Łukasz; Moczko, Jerzy; Weindling, Michael; Kornacka, Alicja; Wróblewska, Katarzyna; Adamczak, Aleksandra; Jopek, Aleksandra; Chojnacka, Karolina; Gadzinowski, Janusz

    2013-08-01

    The aim of this study is to compare a two-wavelength light emitting diode-based tissue oximeter (INVOS), which is designed to show trends in tissue oxygenation, with a four-wavelength laser-based oximeter (FORE-SIGHT), designed to deliver absolute values of tissue oxygenation. Simultaneous values of cerebral tissue oxygenation (StO2) are measured using both devices in 15 term and 15 preterm clinically stable newborns on the first and third day of life. Values are recorded simultaneously in two periods between which oximeter sensor positions are switched to the contralateral side. Agreement between StO2 values before and after the change of sensor position is analyzed. We find that mean cerebral StO2 values are similar between devices for term and preterm babies, but INVOS shows StO2 values spread over a wider range, with wider standard deviations than shown by the FORE-SIGHT. There is relatively good agreement with a bias up to 3.5% and limits of agreement up to 11.8%. Measurements from each side of the forehead show better repeatability for the FORE-SIGHT monitor. We conclude that performance of the two devices is probably acceptable for clinical purposes. Both performed sufficiently well, but the use of FORE-SIGHT may be associated with tighter range and better repeatability of data.

  3. Transcranial laser stimulation improves human cerebral oxygenation

    OpenAIRE

    2016-01-01

    Background and Objective Transcranial laser stimulation of the brain with near‐infrared light is a novel form of non‐invasive photobiomodulation or low‐level laser therapy (LLLT) that has shown therapeutic potential in a variety of neurological and psychological conditions. Understanding of its neurophysiological effects is essential for mechanistic study and treatment evaluation. This study investigated how transcranial laser stimulation influences cerebral hemodynamics and oxygenation in th...

  4. Comparison of Cerebral Oxygen Saturation and Cerebral Perfusion Computed Tomography in Cerebral Blood Flow in Patients with Brain Injury.

    Science.gov (United States)

    Trofimov, Alexey O; Kalentiev, George; Voennov, Oleg; Grigoryeva, Vera

    2016-01-01

    The purpose of this study was to determine the relationship between cerebral tissue oxygen saturation and cerebral blood volume in patients with traumatic brain injury. Perfusion computed tomography of the brain was performed in 25 patients with traumatic brain injury together with simultaneous SctO2 level measurement using cerebral near-infrared oxymetry. The mean age of the injured persons was 34.5±15.6 years (range 15-65); 14 men, 11 women. The Injury Severity Score (ISS) values were 44.4±9.7 (range 25-81). The Glasgow Coma Score (GCS) mean value before the study was 10.6±2.1 (range 5-13). SctO2 ranged from 51 to 89%, mean 62±8.2%. Cerebral blood volume (CBV) values were 2.1±0.67 ml/100 g (min 1.1; max 4.3 ml/100 g). Cerebral blood flow (CBF) was 31.99±13.6 ml/100 g×min. Mean transit time (MTT) values were 5.7±4.5 s (min 2.8; max 34.3 s). The time to peak (TTP) was 22.2±3.1 s. A statistically significant correlation was found between SctO2 level and cerebral blood volume (CBV) level (R=0.9; pperfusion.

  5. Impact of Intraoperative Events on Cerebral Tissue Oximetry in Patients Undergoing Cardiopulmonary Bypass.

    Science.gov (United States)

    Ševerdija, Ervin E; Vranken, Nousjka P A; Teerenstra, Steven; Ganushchak, Yuri M; Weerwind, Patrick W

    2015-03-01

    Previous studies showed that decreased cerebral saturation during cardiac surgery is related to adverse postoperative outcome. Therefore, we investigated the influence of intraoperative events on cerebral tissue saturation in patients undergoing cardiac surgery with cardiopulmonary bypass (CPB). A total of 52 adult patients who underwent cardiac surgery using pulsatile CPB were included in this prospective explorative study. Cerebral tissue oxygen saturation (SctO2) was measured in both the left and right cerebral hemisphere. Intraoperative events, involving interventions performed by anesthesiologist, surgeon, and clinical perfusionist, were documented. Simultaneously, in-line hemodynamic parameters (partial oxygen pressure, partial carbon dioxide pressure, hematocrit, arterial blood pressure, and CPB flow rates) were recorded. Cerebral tissue saturation was affected by anesthetic induction (p retractor (p cardiac surgery. Future studies are needed to identify methods of mitigating periods of reduced cerebral saturation.

  6. Relationship Between Cerebral Oxygenation and Hemodynamic and Oxygen Transport Parameters in Surgery for Acquired Heart Diseases

    Directory of Open Access Journals (Sweden)

    A. I. Lenkin

    2012-01-01

    Full Text Available Objective: to evaluate the relationship between cerebral oxygenation and hemodynamic and oxygen transport parameters in surgical correction of concomitant acquired heart diseases. Subjects and methods. Informed consent was received from 40 patients who required surgery because of concomitant (two or more acquired heart defects. During procedure, perioperative monitoring of oxygen transport and cerebral oxygenation was performed with the aid of PiCCO2 monitor (Pulsion Medical Systems, Germany and a Fore-Sight cerebral oximeter (CASMED, USA. Anesthesia was maintained with propofol and fen-tanyl, by monitoring the depth of anesthesia. Early postoperative intensive therapy was based on the protocol for early targeted correction of hemodynamic disorders. Oxygen transport and cerebral oxygenation parameters were estimated intraopera-tively and within 24 postoperative hours. A statistical analysis including evaluation of Spearman correlations was performed with the aid of SPSS 15.0. Results. During perfusion, there was a relationship between cerebral oximetry values and hemat-ocrit levels, and oxygen partial pressure in the venous blood. Furthermore, a negative correlation between cerebral oximetry values and blood lactate levels was found 30 minutes after initiation of extracorporeal circulation (EC. During the study, there was a positive correlation between cerebral oxygenation and values of cardiac index, central venous saturation, and oxygen delivery index. There was a negative relationship between cerebral oxygenation and extravascular lung water at the beginning of surgery and a correlation between cerebral oximetry values and oxygenation index by the end of the first 24 postoperative hours. Conclusion. The cerebral oxygenation values correlate -with the main determinants of oxygen transport during EC and after cardiac surgical procedures. Cerebral oximetry may be used in early targeted therapy for the surgical correction of acquired combined

  7. Lipopolysaccharide infusion enhances dynamic cerebral autoregulation without affecting cerebral oxygen vasoreactivity in healthy volunteers

    DEFF Research Database (Denmark)

    Berg, Ronan Mg; Plovsing, Ronni R; Evans, Kevin A;

    2013-01-01

    Sepsis may be associated with disturbances in cerebral oxygen transport and cerebral haemodynamic function, thus rendering the brain particularly susceptible to hypoxia. The purpose of this study was to assess the impact of isocapnic hypoxia and hyperoxia on dynamic cerebral autoregulation...... in a human-experimental model of the systemic inflammatory response during the early stages of sepsis....

  8. Non-invasive measurement and validation of tissue oxygen saturation covered with overlying tissues

    Institute of Scientific and Technical Information of China (English)

    Yichao Teng; Haishu Ding; Lan Huang; Yue Li; Quanzhong Shan; Datian Ye; Haiyan Ding; Jenchung Chien; Betau Hwang

    2008-01-01

    In this paper,the biological tissue oxygen saturation(rS02)is obtained non-invasively and in real time based on near infrared spec-troscopy(NIRS)using two emitting wavelengths and two detectors,where the tissue is covered with overlying tissues.Our group devel-oped an NIRS oximeter based on the above principle independently,and validated it using liquid tissue model calibrations and animal experiments.The results indicate that(1)in the normal range of tissue oxygen saturation(40-70%),the rS02 measured by NIRS is accu-rate enough and little influenced by the background absorptions(such as the absorption of water)and overlying tissues(such as fat);(2)during cerebral hypoxia and recovery of three piglets,there is excellent correlation(p<0.001)between cerebral rS02 and jugular venous oxygen saturation(Sj02),meaning that the rS02 can be indicated by the Sj02 to a large extent;during the death of the three piglets induced by heart beat stopping,cerebral rS02 decreases continuously to significantly low levels(<25%)because cerebral blood supply does not exist any more.All the above results are of explicit physiological importance.

  9. Modeling of cerebral oxygen transport based on in vivo microscopic imaging of microvascular network structure, blood flow and oxygenation

    Directory of Open Access Journals (Sweden)

    Louis Gagnon

    2016-08-01

    Full Text Available Oxygen is delivered to brain tissue by a dense network of microvessels, which actively control cerebral blood flow (CBF through vasodilation and contraction in response to changing levels of neural activity. Understanding these network-level processes is immediately relevant for (1 interpretation of functional Magnetic Resonance Imaging (fMRI signals, and (2 investigation of neurological diseases in which a deterioration of neurovascular and neuro-metabolic physiology contributes to motor and cognitive decline. Experimental data on the structure, flow and oxygen levels of microvascular networks are needed, together with theoretical methods to integrate this information and predict physiologically relevant properties that are not directly measurable. Recent progress in optical imaging technologies for high-resolution in vivo measurement of the cerebral microvascular architecture, blood flow, and oxygenation enables construction of detailed computational models of cerebral hemodynamics and oxygen transport based on realistic three-dimensional microvascular networks. In this article, we review state-of-the-art optical microscopy technologies for quantitative in vivo imaging of cerebral microvascular structure, blood flow and oxygenation, and theoretical methods that utilize such data to generate spatially resolved models for blood flow and oxygen transport. These bottom-up models are essential for the understanding of the processes governing brain oxygenation in normal and disease states and for eventual translation of the lessons learned from animal studies to humans.

  10. Inadequate cerebral oxygen delivery and central fatigue during strenuous exercise

    DEFF Research Database (Denmark)

    Nybo, Lars; Rasmussen, Peter

    2007-01-01

    Under resting conditions, the brain is protected against hypoxia because cerebral blood flow increases when the arterial oxygen tension becomes low. However, during strenuous exercise, hyperventilation lowers the arterial carbon dioxide tension and blunts the increase in cerebral blood flow, which...

  11. Cerebral aspects of neonatal extracorporeal membrane oxygenation: a review.

    NARCIS (Netherlands)

    Mol, A.C. de; Liem, K.D.; Heijst, A.F.J. van

    2013-01-01

    Background: Neonatal extracorporeal membrane oxygenation (ECMO) is a lifesaving therapeutic approach in newborns suffering from severe, but potentially reversible, respiratory insufficiency, mostly complicated by neonatal persistent pulmonary hypertension. However, cerebral damage, intracerebral hem

  12. Cerebral oxygenation and haemodynamic effects induced by nimodipine in healthy subjects.

    Science.gov (United States)

    Canova, Daniela; Roatta, Silvestro; Micieli, Giuseppe; Bosone, Daniele

    2012-01-01

    The cerebrovascular effects of nimodipine are still poorly understood even in the healthy condition; in particular, its effects on tissue oxygenation have never been investigated. The aim of the present study was to investigate changes in cerebral oxygenation and blood volume upon oral administration of nimodipine (90 mg) in the healthy condition. In eight subjects, changes in cerebral tissue oxygenation and blood volume were determined simultaneously with changes in blood velocity of the middle cerebral artery (VMCA) by using, respectively, near infrared spectroscopy (NIRS) and transcranial Doppler ultrasonography (TCD). The subjects also underwent noninvasive assessment of arterial blood pressure (ABP) and end-tidal CO2. TCD and NIRS CO2 reactivity indices were al-so extracted. Nimodipine significantly reduced ABP (11±13%) and increased heart rate, as well as NIRS oxygenation(6.0±4.8%) and blood volume indices (9.4±10.1%), while V(MCA) was not significantly decreased (2.0±3.5%). Nimodipine slightly but significantly reduced the V(MCA) response to changes in pCO2 whereas the CO2 reactivity of NIRS parameters was improved. The observed changes in cerebral tissue oxygenation and blood volume indicate nimodipine-induced cerebrovascular dilation and increased perfusion, while the effect on V(MCA)possibly results from dilation of the insonated artery. The present results cast doubt on the putative nimodipine-induced impairment of CO2 reactivity.

  13. [Evaluation of cerebral oxygenation in newborns with prematurity apnea: new frequency domain NIR oximeter].

    Science.gov (United States)

    Pratesi, S; Donzelli, G

    2000-01-01

    Near infrared spectroscopy (NIRS) is a non invasive, portable, safe technique for monitoring cerebral oxygenation and haemodynamics. A new frequency-domain tissue oximeter based on a multi-distance measurement protocol is presented. The effects of apneic episodes on cerebral and peripheral arterial oxygen saturation (SatO2) in preterm newborns, as monitored by NIRS and by pulse oximetry, are reported. The study population consist of 5 preterms (26 to 30 weeks of gestational age), in the second week of postnatal age, affected by apnea of prematurity. NIRS and pulse oximetric measurements were made contemporarily for a 40-minutes period for each infant. All monitorized apneic events were associated with bradicardia, and resolved spontaneously or after tactile stimulation. As results: a) there was always cerebral deoxygenation in association with apneic events, b) the mean SatO2 as measured by NIRS was slightly lower than the pulse oximeter readings, c) cerebral SatO2 decreased faster and the absolute value of the cerebral SaO2 decrease was greater than that measured peripherally (mean value of 27 versus 13%), d) increases of cerebral deoxyhemoglobin and total hemoglobin and a decrease of oxyhemoglobin were also observed. These preliminary results show that peripheral oxygen saturation measurements as measured by pulse oximetry could not always reflect brain oxygenation.

  14. Cerebral oxygenation is reduced during hyperthermic exercise in humans

    DEFF Research Database (Denmark)

    Rasmussen, P.; Nybo, Lars; Volianitis, Stefanos;

    2010-01-01

    Abstract Aim: Cerebral mitochondrial oxygen tension (P(mito)O(2)) is elevated during moderate exercise, while it is reduced when exercise becomes strenuous, reflecting an elevated cerebral metabolic rate for oxygen (CMRO(2)) combined with hyperventilation-induced attenuation of cerebral blood flow...... (CBF). Heat stress challenges exercise capacity as expressed by increased rating of perceived exertion (RPE). Methods: This study evaluated the effect of heat stress during exercise on P(mito)O(2) calculated based on a Kety-Schmidt-determined CBF and the arterial-to-jugular venous oxygen differences...... in eight males [27 +/- 6 years (mean +/- SD) and maximal oxygen uptake (VO(2max)) 63 +/- 6 mL kg(-1) min(-1)]. Results: The CBF, CMRO(2) and P(mito)O(2) remained stable during 1 h of moderate cycling (170 +/- 11 W, approximately 50% of VO(2max), RPE 9-12) in normothermia (core temperature of 37.8 +/- 0...

  15. Physiological meaning of cerebral oxygen saturation for piglet with hypoxia-ischemia

    Science.gov (United States)

    Ding, Haishu; Huang, Lan; Jen, Chungchien; Hwang, Betau; Lee, Zhiguang; Teng, Yichao; Zheng, Meizhi

    2005-01-01

    The physiological meaning of cerebral oxygen saturation absolute values and the oxygen metabolism of piglet with hypoxia-ischemia (HIE) were researched. The subjects were two piglets. During the total experiment of hypoxia then recovery, the regional cerebral tissue oxygen (rScO2), pulse oxygen saturation (SpO2) were detected non-invasively and the jugular oxygen saturation (SjO2), arterial oxygen saturation (SaO2) were given invasively. The results show that because SjO2 was equal to or larger than rScO2 and SaO2 > ScO2, rScO2 cannot be determined by the weighted sum of SjO2 and SaO2 which had been presented in some papers. According to above-mentioned analysis, the ecchymoma and pathological changes of the vessels due to HIE may be another contribution of rScO2. SjO2 was correlated with SaO2 (R=0.996 and 0.962 for two piglets) and the values of (SaO2-SjO2) are close to constants (29.3+/-8% and 30.3+/-8%).It means that because the subjects were under anesthesia, the oxygen consumption of cerebral tissue kept constants.

  16. Oxygen, a key factor regulating cell behaviour during neurogenesis and cerebral diseases

    Directory of Open Access Journals (Sweden)

    Kuan eZhang

    2011-04-01

    Full Text Available Oxygen is vital to maintain the normal functions of alomost all the organs, especially for brain which is one of the heaviest oxygen consumers in the body. The important roles of oxygen on the brain are not only reflected in the development, but also showed in the pathological processes of many cerebral diseases. In the current review, we summarized the oxygen levels in brain tissues tested by real-time measurements during the embryonic and adult neurogenesis, the cerebral diseases or in the hyperbaric/hypobaric oxygen environment. Oxygen concentration is low in fetal brain (0.01%- 1% and in adult brain (1.5%-7%, decreased during stroke, and increased in hyperbaric oxygen environment. In addition, we reviewed the effects of oxygen tensions on the behaviors of neural stem cells (NSCs in vitro cultures at different oxygen concentration (2%-20% and in vivo niche during different pathological states and in hyperbaric/hypobaric oxygen environment. Moderate hypoxia (3%-10% is known can promote the proliferation of NSCs and enhance the differentiation of NSCs into the TH-positive neurons. Next, we briefly presented the oxygen-sensitive molecular mechanisms regulating NSCs proliferation and differentiation recently found including the Notch, BMP and Wnt pathways. Finally, the future perspectives about the roles of oxygen on brain and NSCs were given.

  17. Cerebral oxygen metabolism in patients with early Parkinson's disease

    DEFF Research Database (Denmark)

    Borghammer, Per; Cumming, Paul; Østergaard, Karen;

    2012-01-01

    AIM: Decreased activity of the mitochondrial electron transport chain (ETC) has been implicated in the pathogenesis of Parkinson's disease (PD). This model would most likely predict a decrease in the rate of cerebral oxygen consumption (CMRO(2)). To test this hypothesis, we compared CMRO(2...

  18. Effects of propofol versus sevoflurane on cerebral oxygenation and cognitive outcome in patients with impaired cerebral oxygenation

    Directory of Open Access Journals (Sweden)

    Guo JY

    2016-01-01

    Full Text Available Jun-ying Guo,1,* Jie-yu Fang,1,* San-rong Xu,2 Ming Wei,1 Wen-qi Huang1 1Department of Anesthesia, the First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, 2Department of Anesthesia, Zhangzhou Municipal Hospital of Fujian Province, Zhangzhou, Fujian, People’s Republic of China *These authors contributed equally to this work Background: Postoperative neurocognitive dysfunction induced by anesthetics, particularly in elderly patients with impaired oxygenation, is a common complication of surgery and is eliciting increased interest in clinical practice. To investigate the effects of anesthetics on neurocognition, we compared the effects of propofol versus sevoflurane on cerebral oxygenation and cognitive outcome in patients with impaired cerebral oxygenation undergoing general anesthesia. Methods: Sixty-three patients with impaired cerebral oxygenation (jugular venous bulb oxygen saturation [SjvO2] <50% or cerebral blood flow/cerebral metabolic rate of oxygen ([CBF/CMRO2] ≤15% undergoing elective abdominal surgery were randomly allocated into propofol group (group P or sevoflurane group (group S. The clinical parameters and jugular venous bulb blood gas analysis were monitored throughout the surgical procedure. Cognitive function was assessed with the mini-mental state examination and Montreal Cognitive Assessment at day 1 and day 7 following surgery. S100β protein in plasma was measured using enzyme-linked immunosorbent assay. Results: The SjvO2 increased during anesthesia induction and surgery when compared to baseline but had no significant difference between group P and group S. When compared to baseline, the CBF/CMRO2 was increased only at the end of surgery and extubation in group P; however, the CBF/CMRO2 in group S was increased during anesthesia induction at 1 hour, 2 hours, end of surgery, and extubation. Furthermore, the CBF/CMRO2 in group S was significantly higher than that in group P during anesthesia

  19. Cerebral oxygen extraction, oxygen consumption, and regional cerebral blood flow during the aura phase of migraine

    DEFF Research Database (Denmark)

    Friberg, L; Olesen, Jes; Lassen, N A

    1994-01-01

    The aura phase of migraine is associated with focal blood flow changes, but it has been largely unknown whether these changes are correlated to changes in the cerebral metabolism.......The aura phase of migraine is associated with focal blood flow changes, but it has been largely unknown whether these changes are correlated to changes in the cerebral metabolism....

  20. Noninvasive cerebral blood oxygenation monitoring: clinical test of multiwavelength optoacoustic system

    Science.gov (United States)

    Petrov, Y. Y.; Prough, D. S.; Petrova, I.; Patrikeev, I. A.; Cicenaite, I.; Esenaliev, R. O.

    2007-02-01

    Continuous monitoring of cerebral blood oxygenation is critically important for treatment of patients with life-threatening conditions like severe brain injury or during cardiac surgery. We designed and built a novel multiwavelength optoacoustic system for noninvasive, continuous, and accurate monitoring of cerebral blood oxygenation. We use an Optical Parametric Oscillator as a light source. We successfully tested the system in vitro as well as in vivo in large animals (sheep) through thick tissues overlying blood vessels which drain venous blood out of the brain (e.g., superior sagittal sinus or jugular vein). Here we present the results of clinical tests of the system for continuous noninvasive cerebral blood oxygenation monitoring in the internal jugular vein of healthy volunteers. We applied our custom-built optoacoustic probe (which incorporated a wide-band acoustic transducer and an optical fiber) to the neck area overlying the internal jugular vein. We performed measurements with volunteers at 18 wavelengths in the near-infrared spectral range. Despite a thick layer of overlying connective tissue and low energy used in the experiments, we recorded signals with high signal-to-noise ratios for all volunteers. We found that the temporal (independent of signal amplitude) parameters of recorded profiles for different levels of blood oxygenation correlated well with the spectrum of effective attenuation coefficients of blood.

  1. Effects of rapamycin on cerebral oxygen supply and consumption during reperfusion after cerebral ischemia.

    Science.gov (United States)

    Chi, O Z; Barsoum, S; Vega-Cotto, N M; Jacinto, E; Liu, X; Mellender, S J; Weiss, H R

    2016-03-01

    Activation of the mammalian target of rapamycin (mTOR) leads to cell growth and survival. We tested the hypothesis that inhibition of mTOR would increase infarct size and decrease microregional O2 supply/consumption balance after cerebral ischemia-reperfusion. This was tested in isoflurane-anesthetized rats with middle cerebral artery blockade for 1h and reperfusion for 2h with and without rapamycin (20mg/kg once daily for two days prior to ischemia). Regional cerebral blood flow was determined using a C(14)-iodoantipyrine autoradiographic technique. Regional small-vessel arterial and venous oxygen saturations were determined microspectrophotometrically. The control ischemic-reperfused cortex had a similar blood flow and O2 consumption to the contralateral cortex. However, microregional O2 supply/consumption balance was significantly reduced in the ischemic-reperfused cortex. Rapamycin significantly increased cerebral O2 consumption and further reduced O2 supply/consumption balance in the reperfused area. This was associated with an increased cortical infarct size (13.5±0.8% control vs. 21.5±0.9% rapamycin). We also found that ischemia-reperfusion increased AKT and S6K1 phosphorylation, while rapamycin decreased this phosphorylation in both the control and ischemic-reperfused cortex. This suggests that mTOR is important for not only cell survival, but also for the control of oxygen balance after cerebral ischemia-reperfusion.

  2. Cerebral blood flow and oxygen metabolism in the Rett syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Yoshikawa, Hideto; Fueki, Noboru; Suzuki, Hisaharu; Sakuragawa, Norio; Iio, Masaaki (National Central Hospital for Mental, Nervous and Muscular Disorders, Tokyo (Japan))

    1992-05-01

    Positron emission tomography (PET) was performed on six patients with the Rett syndrome and the results were compared with the concurrent clinical status of the patients. The cerebral metabolic rate of oxygen (CMRO{sub 2}) was low in five patients, and oxygen extraction fraction (OEF) was low in four patients; both had a tendency to decline with advancing age. Although the cause is unknown, it is suggested that impaired oxidative metabolism exists in the Rett syndrome. An analysis of the distribution among brain regions showed that the ratios of values for the frontal cortex to those for the temporal cortex for both the cerebral blood flow (CBF) and CMRO{sub 2} were lower than those for the controls, which may indicate the loss of of hyperfrontality in the Rett syndrome. Distribution of brain metabolism may be immature in the Rett syndrome. (author).

  3. Influence of remote ischemic preconditioning on cerebral oxygen metabolism and cerebral blood flow indexes of patients with ischemic cerebrovascular disease

    Institute of Scientific and Technical Information of China (English)

    Hui Lu; Ning-Ning Cui; Bin-Cheng Wang

    2016-01-01

    Objective:To study the influence of remote ischemic preconditioning on cerebral oxygen metabolism and cerebral blood flow indexes of patients with ischemic cerebrovascular disease. Methods:A total of 58 patients with ischemic cerebrovascular disease in our hospital from April 2015 to January 2016 were selected as the study object, and 58 patients were randomly divided into two groups, 29 patients in control group were treated with routine treatment, 29 patients in observation group were treated with remote ischemic preconditioning on the basic treatment of control group, then the cerebral oxygen metabolism and cerebral blood flow indexes of two groups before the treatment and at first, third and sixth month after the treatment were respectively detected and compared.Results:The cerebral oxygen metabolism and cerebral blood flow indexes of two groups before the treatment all showed no significant differences (allP>0.05), while the cerebral oxygen metabolism and cerebral blood flow indexes of observation group at first, third and sixth month after the treatment were all significantly better than those before the treatment, and the results were all significantly better than those of control group at the same time too (allP>0.05).Conclusions: The influence of remote ischemic preconditioning on cerebral oxygen metabolism and cerebral blood flow indexes of patients with ischemic cerebrovascular disease are better, and its application value for the patients with ischemic cerebrovascular disease is higher.

  4. Activated oxygen alters cerebral microvascular responses in newborn pigs

    Energy Technology Data Exchange (ETDEWEB)

    Leffler, C.W.; Busiia, D.W.; Armstead, W.M.; Mirro, R.; Thelin, O. (Univ. of Tennessee, Memphis (United States))

    1990-02-26

    In piglets, cerebral ischemia/reperfusion blocks prostanoid dependent cerebral vasodilation to hypercapnia (CO{sub 2}) and hypotension but not prostanoid independent dilation to isoproterenol (Isu) or constriction to norepinephrine (NE). Ischemia/reperfusion increases activated-O{sub 2} production by piglet brains. Using cranial windows in piglets, the authors investigated the hypothesis that activated oxygen can block prostanoid dependent cerebral vasodilator responses to CO{sub 2} and hypotension without altering responses to Isu and NE. Exposure to an activated oxygen generating system of xanthine oxidase, hypoxanthine, and Fe that made about 3 times the activated-O{sub 2} on the brain surface as ischemia/reperfusion caused reversible pial arteriolar dilation. After exposure, pial arteriolar dilation was reduced to CO{sub 2} and hypotension but not to Isu. NE constrictor responses were also unaltered. H{sub 2}O{sub 2} or H{sub 2}O{sub 2} + Fe caused constriction followed by reversible dilation. After exposure, pial arteriolar dilation in response to CO{sub 2} and hypotension was not altered. However, addition of xanthine oxidase and hypoxanthine with H{sub 2}O{sub 2} and Fe totally eliminated pial arteriolar dilator responses to CO{sub 2} and hypotension but did not decrease dilation caused by Isu or constriction caused by NE. The authors conclude that activated oxygen could produce the altered prostanoid dependent pial arteriolar responses observed following ischemia in piglets.

  5. Oxygen radicals, inflammation, and tissue injury.

    Science.gov (United States)

    Ward, P A; Warren, J S; Johnson, K J

    1988-01-01

    Inflammatory reactions often result in the activation and recruitment of phagocytic cells (e.g., neutrophils and/or tissue macrophages) whose products result in injury to the tissue. In killing of endothelial cells by activated neutrophils as well as in lung injury produced by either activated neutrophils or activated macrophages there is evidence that H2O2 and iron play a role. HO. may be a key oxygen product related to the process of injury. Endothelial cells in some vascular compartments may be susceptible to neutrophil mediated injury in a manner that is independent of oxygen radicals. On the basis of in vitro observations, a synergy exits between platelets and neutrophils, resulting in enhanced oxygen radical formation by the latter. Finally, the cytokines, interleukin 1 and tumor necrosis factor, released from macrophages have both direct stimulatory effects on oxygen radical formation in neutrophils and can "prime" macrophages for enhanced oxygen radical responses to other agonists. Cytokines may also alter endothelial cells rendering them more susceptible to oxygen radical mediated injury by neutrophils. This suggests a complex network of interactions between phagocytic cells and peptide mediators, the result of which is acute, oxygen radical mediated tissue injury.

  6. Cerebral oxygenation and metabolism during exercise following three months of endurance training in healthy overweight males

    DEFF Research Database (Denmark)

    Seifert, T; Rasmussen, P; Brassard, P

    2009-01-01

    Endurance training improves muscular and cardiovascular fitness, but the effect on cerebral oxygenation and metabolism remains unknown. We hypothesized that 3 mo of endurance training would reduce cerebral carbohydrate uptake with maintained cerebral oxygenation during submaximal exercise. Healthy...... with a lower plasma epinephrine concentration (P exercising at 70% of maximal oxygen uptake (approximately 211 W). Before training, both OCI (3.9 +/- 0.9) and DeltaP(Mito)O(2) (-22 mmHg) decreased (P ... attenuates the cerebral metabolic response to submaximal exercise, as reflected in a lower carbohydrate uptake and maintained cerebral oxygenation....

  7. Comparison of cerebral oxygen saturation in premature infants by near-infrared spatially resolved spectroscopy: observations on probe-dependent bias

    DEFF Research Database (Denmark)

    Sorensen, Line C; Leung, Terence S; Greisen, Gorm

    2008-01-01

    Spatially resolved spectroscopy (SRS) allows the estimation of absolute tissue oxygen saturation, the ratio of oxygenated to total hemoglobin concentration, which may facilitate the comparison of results among patients. Eighty-two premature infants were included over two years. The cerebral tissue...

  8. [Raman spectra of monkey cerebral cortex tissue].

    Science.gov (United States)

    Zhu, Ji-chun; Guo, Jian-yu; Cai, Wei-ying; Wang, Zu-geng; Sun, Zhen-rong

    2010-01-01

    Monkey cerebral cortex, an important part in the brain to control action and thought activities, is mainly composed of grey matter and nerve cell. In the present paper, the in situ Raman spectra of the cerebral cortex of the birth, teenage and aged monkeys were achieved for the first time. The results show that the Raman spectra for the different age monkey cerebral cortex exhibit most obvious changes in the regions of 1000-1400 and 2800-3000 cm(-1). With monkey growing up, the relative intensities of the Raman bands at 1313 and 2885 cm(-1) mainly assigned to CH2 chain vibrational mode of lipid become stronger and stronger whereas the relative intensities of the Raman bands at 1338 and 2932 cm(-1) mainly assigned to CH3 chain vibrational mode of protein become weaker and weaker. In addition, the two new Raman bands at 1296 and 2850 cm(-1) are only observed in the aged monkey cerebral cortex, therefore, the two bands can be considered as a character or "marker" to differentiate the caducity degree with monkey growth In order to further explore the changes, the relative intensity ratios of the Raman band at 1313 cm(-1) to that at 1338 cm(-1) and the Raman band at 2885 cm(-1) to that at 2 932 cm(-1), I1313/I1338 and I2885/I2932, which are the lipid-to-protein ratios, are introduced to denote the degree of the lipid content. The results show that the relative intensity ratios increase significantly with monkey growth, namely, the lipid content in the cerebral cortex increases greatly with monkey growth. So, the authors can deduce that the overmuch lipid is an important cause to induce the caducity. Therefore, the results will be a powerful assistance and valuable parameter to study the order of life growth and diagnose diseases.

  9. Cerebral regional oxygen saturation monitoring in pediatric malfunctioning shunt patients☆,☆☆,★

    Science.gov (United States)

    Abramo, Thomas J.; Zhou, Chuan; Estrada, Cristina; Drayna, Patrick C.; Locklair, Matthew R.; Miller, Renee; Pearson, Matthew; Tulipan, Noel; Arnold, Donald H.

    2014-01-01

    Background Shunt malfunction produces increased intracranial pressure causing decreased cerebral regional perfusion and tissue O2sat. Cerebral regional oxygen saturation (rSO2) by near-infrared spectroscopy represents tissue perfusion and oxygen saturation. Cerebral rSO2 is used to detect cerebral ischemia in pediatric clinical settings. Objective The objective of the study was to determine the reliability of cerebral rSO2 in pediatric malfunctioning shunt. Methods A prospective observational study of pediatric patients presented to the pediatric emergency department was conducted. Confirmed malfunctioning shunt subjects had cerebral rSO2 monitoring. Results A total of 131 malfunctioning shunt subjects had cerebral rSO2 monitoring. Patient's central trend and intrasubject variability of cerebral rSO2 readings for left and right probe and malfunction sites (n = 131) are as follows: VariableOverall, mean SO2Distal, mean SO2Proximal, mean rSO2PLeft cerebral rSO2 trend69.1 (10.7)67.7 (9.81)70.0 (11.17).23Right cerebral rSO2 trend71.3 (9.6)70.5 (8.13)71.8 (10.40).42Left cerebral rSO2 variability3.57 (2.04)4.72 (2.55)2.88 (1.24)<.001Right cerebral rSO2 variability3.46 (1.95)3.77 (2.20)3.28 (1.77).19 Intrasubject left and right rSO2 Pearson correlation was −0.46 to 0.98 (mean ± SD, 0.35 ± 0.34; median, 0.34; interquartile range, 0.06–0.61). The correlation coefficients of 99 subjects between left and right rSO2 was significantly different (P < .001), suggesting that intrasubjects' left and right rSO2 are highly correlated. Sample mean difference between left and right rSO2 were −1.7% (95% confidence interval [CI], −1.8 to −1.6; P < .001) supporting overall left lower than right. Intraclass correlation for left rSO2 was 87.4% (95% CI, 87.2%−87.6%), and that for right rSO2 was 83.8% (95% CI, 83.8%−84%), showing intersubject differences accounting for the variation, and relative to intersubject variation, intrasubjects readings are consistent. Intrasubjects

  10. Activation-induced resetting of cerebral oxygen and glucose uptake in the rat

    DEFF Research Database (Denmark)

    Madsen, P L; Linde, R; Hasselbalch, S G;

    1998-01-01

    In the clinical setting it has been shown that activation will increase cerebral glucose uptake in excess of cerebral oxygen uptake. To study this phenomenon further, this study presents an experimental setup that enables precise determination of the ratio between cerebral uptake of glucose...... and oxygen in the awake rat. Global CBF was measured by the Kety-Schmidt technique, and the ratio between cerebral uptake rates for oxygen, glucose, and lactate was calculated from cerebral arterial-venous differences. During baseline conditions, rats were kept in a closed box designed to minimize...

  11. Simple exercises that significantly increase cerebral blood flow and cerebral oxygenation

    CERN Document Server

    Gersten, Alexander; Raz, Amir; Fried, Robert

    2011-01-01

    We tested the hypothesis that simple exercises may significantly increase cerebral blood flow (CBF) and/or cerebral oxygenation. Eighteen subjects ranging in age from nineteen to thirty nine participated in a four-stage study during which measurements of end tidal CO_2 (EtCO2 - by capnometer) and local brain oxygenation (by near-infrared spectroscopy (NIRS) sensor) were taken. The four stages were 1) baseline, 2) breathing exercises, 3) solving an arithmetic problem, and 4) biofeedback. During the breathing exercises there was a significant increase in EtCO2 indicating a significant increase in global CBF. The increase in global CBF was estimated on the basis of a theoretical model. During the arithmetic and biofeedback tasks there was a significant increase in the local (Fp1) oxygenation, but it varied between the different participants. The results may lead to new clinical applications of CBF and brain oxygenation monitoring and behavioral control. We foresee future more detailed investigations in the contr...

  12. Correlation between cerebral oxygen metabolism and cerebral blood flow simultaneously measured before and after acetazolamide administration

    Science.gov (United States)

    Yamaguchi, Hiroichiro; Yamauchi, Hideto; Hazama, Shiro; Hamamoto, Hirotsugu; Inoue, Nobuhiro

    1999-10-01

    The cerebral circulation and metabolism of ten preoperative cardiac surgery patients were assessed. Alterations in regional cerebral blood flow (rCBF), measured by 123I-N- isopropyl-p-iodo-amphetamine single-photon emission computed tomography, and in cerebral oxygen metabolism, simultaneously detected by near-infrared spectroscopy (NIRS) before and after acetazolamide administration, were investigated. The rCBF (ml/min/100 g) increased significantly from 40.21 +/- 7.65 to 56.24 +/- 13.69 (p equals 0.001), and a significant increase in oxyhemoglobin (Oxy-Hb) of 13.9% (p equals 0.0022) and total hemoglobin (Total-Hb) of 5.7% (0.0047) along with a significant decrease in deoxyhemoglobin (Deoxy-Hb) of 8.9% (p equals 0.0414) were observed concomitantly. Thus, the Oxy-Hb/Total- Hb ratio (%Oxy-Hb) rose significantly from 67.26 +/- 9.82% to 72.98 +/- 8.09% (p equals 0.0022). Examination of the relationships between individual parameters showed that the percentage changes in rCBF and Oxy-Hb were significantly correlated (r equals 0.758, p equals 0.011). The percentage changes in rCBF and %Oxy-Hb were also correlated significantly (r equals 0.740, p equals 0.014). In conclusion, this evidence suggested that NIRS is able to detect relative changes in cerebral hemodynamics and reflect luxury perfusion induced by acetazolamide.

  13. Influence of moderate hypothermia on cerebral oxygenation in pigs with intracranial hypertension

    Institute of Scientific and Technical Information of China (English)

    Yinghui Bao; Yumin Liang; Jiyao Jiang; Qizhong Luo; Yicheng Lu

    2007-01-01

    BACKGROUND: Moderate hypothermia is one of the effective therapeutic methods for head injury in recent years, there are many mechanisms of moderate hypothermia for brain protection, and its influence on cerebral oxygenation is also one of them.OBJECTIVE: To observe the influence of moderate hypothermia on cerebral oxygenation of animals with acute intracranial hypertension, and further investigate the protective mechanism of moderate hypothermia. DESIGN: A randomized controlled trial.SETTING: Department of Neurosurgery, Renji Hospital affiliated to the Medical College of Shanghai Jiao Tong University.MATERIALS: Twenty healthy little pigs, either male or female, weighing 4.5 - 5.5 kg, were used. Neurotrend-typed multiparameter monitoring system (Diametrics Company, British); CMA/100micro-injection pump (Carnegie Company, Sweden).METHODS: The experiment was conducted in the Changzheng Hospital affiliated to the Second Military Medical University of Chinese PLA in November, 2001. The pigs were randomized into two groups: the normothermia group (control group, n =10) and moderate hypothermia group (n =10). ①Bilateral femoral arteries were separated, one was connected to pressometer for monitoring mean arterial pressure (MEP), and the other for analysis of blood gases [including peripheral blood Ph value, arterial partial pressure of carbon dioxide (PaCCh), arterial partial pressure of carbon dioxide (PaCO2), HCO3-].②Rectal temperature was monitored with mercurial thermometer.③Intracranial pressure was monitored using Camino optic ICP probe placed in the subdural space. ④Neurotrend multiparameter monitoring sensor was inserted into the white matter for about 4 cm to determine cerebral perfusion pressure (CPP, CPP=MAP(ICP), brain tissue partial oxygen pressure (PO2), partial pressure of carbon dioxide (PCCh), HCO3- and brain temperature. The rectal temperature of animals in the moderate hypothermia group was lowered to 34℃ using ice bags, and the body

  14. Metabolic Prosthesis for Oxygenation of Ischemic Tissue

    Energy Technology Data Exchange (ETDEWEB)

    Greenbaum, Elias [ORNL

    2009-01-01

    This communication discloses new ideas and preliminary results on the development of a "metabolic prosthesis" for local oxygenation of ischemic tissue under physiological neutral conditions. We report for the first time the selective electrolysis of physiological saline by repetitively pulsed charge-limited electrolysis for the production of oxygen and suppression of free chlorine. For example, using 800 A amplitude current pulses and <200 sec pulse durations, we demonstrated prompt oxygen production and delayed chlorine production at the surface of a shiny 0.85 mm diameter spherical platinum electrode. The data, interpreted in terms of the ionic structure of the electric double layer, suggest a strategy for in situ production of metabolic oxygen via a new class of "smart" prosthetic implants for dealing with ischemic disease such as diabetic retinopathy. We also present data indicating that drift of the local pH of the oxygenated environment can be held constant using a feedback-controlled three electrode electrolysis system that chooses anode and cathode pair based on pH data provided by local microsensors. The work is discussed in the context of diabetic retinopathy since surgical techniques for multielectrode prosthetic implants aimed at retinal degenerative diseases have been developed.

  15. Cerebral oxygenation decreases during exercise in humans with beta-adrenergic blockade

    DEFF Research Database (Denmark)

    Seifert, T.; Rasmussen, P.; Secher, Niels H.

    2009-01-01

    AIM: Beta-blockers reduce exercise capacity by attenuated increase in cardiac output, but it remains unknown whether performance also relates to attenuated cerebral oxygenation. METHODS: Acting as their own controls, eight healthy subjects performed a continuous incremental cycle test to exhaustion...... with or without administration of the non-selective beta-blocker propranolol. Changes in cerebral blood flow velocity were measured with transcranial Doppler ultrasound and those in cerebral oxygenation were evaluated using near-infrared spectroscopy and the calculated cerebral mitochondrial oxygen tension...

  16. The effects of sevoflurane and propofol anesthesia on cerebral oxygenation in gynecological laparoscopic surgery

    OpenAIRE

    Kim, Sung-Jin; Kwon, Jae Young; Cho, Ah-Reum; Kim, Hae Kyu; Kim, Tae Kyun

    2011-01-01

    Background Both the Trendelenburg position and pneumoperitoneum with carbon dioxide have been reported to increase intracranial pressure (ICP) and to alter cerebral blood flow or cerebral blood volume. Also anesthetic agents have variable effects on cerebral hemodynamics and ICP. The present study was conducted to determine whether regional cerebral oxygen saturation (rSO2) values differ between propofol and sevoflurane anesthesia during laparoscopic surgery in the Trendelenburg position. Met...

  17. Optical characterization of two-layered turbid media for non-invasive, absolute oximetry in cerebral and extracerebral tissue.

    Directory of Open Access Journals (Sweden)

    Bertan Hallacoglu

    Full Text Available We introduce a multi-distance, frequency-domain, near-infrared spectroscopy (NIRS method to measure the optical coefficients of two-layered media and the thickness of the top layer from diffuse reflectance measurements. This method features a direct solution based on diffusion theory and an inversion procedure based on the Levenberg-Marquardt algorithm. We have validated our method through Monte Carlo simulations, experiments on tissue-like phantoms, and measurements on the forehead of three human subjects. The Monte Carlo simulations and phantom measurements have shown that, in ideal two-layered samples, our method accurately recovers the top layer thickness (L, the absorption coefficient (µ a and the reduced scattering coefficient (µ' s of both layers with deviations that are typically less than 10% for all parameters. Our method is aimed at absolute measurements of hemoglobin concentration and saturation in cerebral and extracerebral tissue of adult human subjects, where the top layer (layer 1 represents extracerebral tissue (scalp, skull, dura mater, subarachnoid space, etc. and the bottom layer (layer 2 represents cerebral tissue. Human subject measurements have shown a significantly greater total hemoglobin concentration in cerebral tissue (82±14 µM with respect to extracerebral tissue (30±7 µM. By contrast, there was no significant difference between the hemoglobin saturation measured in cerebral tissue (56%±10% and extracerebral tissue (62%±6%. To our knowledge, this is the first time that an inversion procedure in the frequency domain with six unknown parameters with no other prior knowledge is used for the retrieval of the optical coefficients and top layer thickness with high accuracy on two-layered media. Our absolute measurements of cerebral hemoglobin concentration and saturation are based on the discrimination of extracerebral and cerebral tissue layers, and they can enhance the impact of NIRS for cerebral hemodynamics and

  18. Effects of transection of cervical sympathetic trunk on cerebral infarct volume and oxygen free radical levels in rats with focal cerebral ischemia/reperfusion injury

    Institute of Scientific and Technical Information of China (English)

    Liangzhi Xiong; Yongxia Shi; Feng Xiao; Qingxiu Wang

    2008-01-01

    BACKGROUND: Stellate ganglion block (SGB) plays a protective role on the brain, but the precise mechanism of action is not clear.OBJECTIVE: To simulate SGB by transection of the cervical sympathetic trunk (TCST) and to investigate the TCST effects on changes in cerebral infarct volume and oxygen free radical levels in rats with focal cerebral ischemia/reperfusion injury.DESIGN, TIME AND SETTING: A complete randomized control animal experiment was performed at the Institute of Neurological Diseases of Taihe Hospital, Yunyang Medical College from February to December 2005.MATERIALS: A total of 101 healthy Wistar rats, weighing 280-320g, of both genders, aged 17-18 weeks, were used in this study. 2,3,5-triphenyltetrazolium chloride (TTC) was purchased from Changsha Hongyuan Biological Company. Superoxide dismutase (SOD), malondialdehyde (MDA) and nitric oxide (NO) assay kits were provided by Nanjing Jiancheng Bioengineering Institute.METHODS: Rats were randomly divided into a TCST group, a model group and a sham operation group. Successful models were included in the final analysis, with at least 20 rats in each group. After TCST, rat models of focal cerebral ischemia/reperfusion injury were established in the TCST group by receiving middle cerebral artery occlusion (MCAO) by the intraluminal suture method for 2 hours, followed by 24 hours of reperfusion. Rat models of focal cerebral ischemia/reperfusion injury were made in the model group. Rats in the sham operation group underwent experimental procedures as for the model group, threading depth of 10mm, and middle cerebral artery was not ligated.MAIN OUTCOME MEASURES: Brain tissue sections of ten rats from each group were used to measure cerebral infarct volume by TTC staining. Brain tissue homogenate of another ten rats from each group was used to detect SOD activities, MDA contents and NO levels. Rat neurological function was assessed by neurobehavioral measures.RESULTS: Cerebral infarct volume was bigger in the

  19. Cerebral blood oxygenation changes induced by visual stimulation in humans

    Science.gov (United States)

    Wenzel, Rudiger; Obrig, Hellmuth; Ruben, Jan; Villringer, Kersten; Thiel, Andreas; Bernarding, Johannes; Dirnagl, Ulrich; Villringer, Arno

    1996-10-01

    We examined local changes of cerebral oxygenation in response to visual stimuli by means of near infrared spectroscopy. A sharply outlined colored moving stimulus which is expected to evoke a broad activation of the striate and prestriate cortex was presented to sixteen healthy subjects. Six of these subjects were also exposed to a colored stationary and a gray stationary stimulus. In two subjects the colored moving stimulus was tested against the colored stationary with an optode position presumably over area V5/MT. As a control condition, subjects performed a simple finger opposition task. Since the calcarine fissure varies greatly with respect to bony landmarks, optodes were positioned individually according to 3D reconstructed magnetic resonance imaging (MRI). Concentration changes in oxyhemoglobin (oxy-Hb) and deoxyhemoglobin (deoxy-Hb) were continuously monitored with a temporal resolution of 1 s, using an NIRO 500. In response to the visual stimulus, the grand average across all sixteen subjects resulted in a significant increase in oxy-Hb of 0.33 +/- 0.09 arbitrary units mirrored by a significant decrease in deoxy-Hb of -0.18 +/- 0.02 arbitrary units, while the motor control condition elicited no significant changes in any parameters. When the near infrared spectroscopy probes were positioned over area V5/MT, the drop of deoxy-Hb associated with the moving stimulus was significantly more pronounced than with the stationary stimulus in both subjects examined. No significant differences between the visual stimuli were observed at the optode position close to the calcarine fissure. The oxygenation changes observed in this study are consistent with the pattern we have reported for motor activation. They are in line with physiological considerations and functional MRI studies relying on blood oxygenation level-dependent contrast.

  20. Cerebral oxygen saturation: graded response to carbon dioxide with isoxia and graded response to oxygen with isocapnia.

    Directory of Open Access Journals (Sweden)

    W Alan C Mutch

    Full Text Available BACKGROUND: Monitoring cerebral saturation is increasingly seen as an aid to management of patients in the operating room and in neurocritical care. How best to manipulate cerebral saturation is not fully known. We examined cerebral saturation with graded changes in carbon dioxide tension while isoxic and with graded changes in oxygen tension while isocapnic. METHODOLOGY/PRINCIPAL FINDINGS: The study was approved by the Research Ethics Board of the University Health Network at the University of Toronto. Thirteen studies were undertaken in healthy adults with cerebral oximetry by near infrared spectroscopy. End-tidal gas concentrations were manipulated using a model-based prospective end-tidal targeting device. End-tidal carbon dioxide was altered ±15 mmHg from baseline in 5 mmHg increments with isoxia (clamped at 110±4 mmHg. End-tidal oxygen was changed to 300, 400, 500, 80, 60 and 50 mmHg under isocapnia (37±2 mmHg. Twelve studies were completed. The end-tidal carbon dioxide versus cerebral saturation fit a linear relationship (R(2 = 0.92±0.06. The end-tidal oxygen versus cerebral saturation followed log-linear behaviour and best fit a hyperbolic relationship (R(2 = 0.85±0.10. Cerebral saturation was maximized in isoxia at end-tidal carbon dioxide of baseline +15 mmHg (77±3 percent. Cerebral saturation was minimal in isocapnia at an end-tidal oxygen tension of 50 mmHg (61±3 percent. The cerebral saturation during normoxic hypocapnia was equivalent to normocapnic hypoxia of 60 mmHg. CONCLUSIONS/SIGNIFICANCE: Hypocapnia reduces cerebral saturation to an extent equivalent to moderate hypoxia.

  1. Higher cerebral oxygen saturation may provide higher urinary output during continuous regional cerebral perfusion

    Directory of Open Access Journals (Sweden)

    Tomoyasu Takahiro

    2008-10-01

    Full Text Available Abstract Objective We examined the hypothesis that higher cerebral oxygen saturation (rSO2 during RCP is correlated with urinary output. Methods Between December 2002 and August 2006, 12 patients aged 3 to 61 days and weighing 2.6 to 3.4 kg underwent aortic arch repair with RCP. Urinary output and rSO2 were analyzed retrospectively. Data were assigned to either of 2 groups according to their corresponding rSO2: Group A (rSO2 ≦ 75% and Group B (rSO2 Results Seven and 5 patients were assigned to Group A and Group B, respectively. Group A was characterized by mean radial arterial pressure (37.9 ± 9.6 vs 45.8 ± 7.8 mmHg; P = 0.14 and femoral arterial pressure (6.7 ± 6.1 vs 20.8 ± 14.6 mmHg; P = 0.09 compared to Group B. However, higher urinary output during CPB (1.03 ± 1.18 vs 0.10 ± 0.15 ml·kg-1·h-1; P = 0.03. Furthermore our results indicate that a higher dose of Chlorpromazine was used in Group A (2.9 ± 1.4 vs 1.7 ± 1.0 mg/kg; P = 0.03. Conclusion Higher cerebral oxygenation may provide higher urinary output due to higher renal blood flow through collateral circulation.

  2. Impact of Intraoperative Events on Cerebral Tissue Oximetry in Patients Undergoing Cardiopulmonary Bypass

    NARCIS (Netherlands)

    Severdija, E.E.; Vranken, N.P.; Teerenstra, S.; Ganushchak, Y.M.; Weerwind, P.W.

    2015-01-01

    Previous studies showed that decreased cerebral saturation during cardiac surgery is related to adverse postoperative outcome. Therefore, we investigated the influence of intraoperative events on cerebral tissue saturation in patients undergoing cardiac surgery with cardiopulmonary bypass (CPB). A t

  3. Extra-cerebral oxygenation influence on near-infrared-spectroscopy-determined frontal lobe oxygenation in healthy volunteers

    DEFF Research Database (Denmark)

    Sørensen, Henrik; Rasmussen, Peter; Siebenmann, Christoph

    2015-01-01

    regression analysis estimated the influence of extra-cerebral oxygenation as exemplified by skin oxygenation (Sskin O2 ) on Sc O2 in 21 healthy subjects exposed to whole-body exercise in hypoxia (Fi O2 = 12%; n = 10) and normoxia (n = 12), whole-body heating, hyperventilation (n = 21), administration...

  4. Simultaneous Monitoring of Vascular Oxygenation and Tissue Oxygen Tension of Breast Tumors Under Hyperbaric Oxygen Exposure

    Science.gov (United States)

    2008-04-01

    biological tissue, and allow for detection of specific light-absorbing chromophores in human in vivo, such as oxygenated and deoxygenated hemoglobin...spectra from tumor tissue. Briefly, continuous wave (CW) light from a 20 W tungsten-halogen light source (HL-2000HP, ocean optics, FL) is coupled...spectrometer (USB2000, Ocean optics, FL). The broadband light diffuse spectrometer provides reflectance spectra from 400 to 900 nm. According to

  5. Effect of propofol and remifentanil on cerebral perfusion and oxygenation in pigs

    DEFF Research Database (Denmark)

    Mikkelsen, Mai Louise Grandsgaard; Ambrus, Rikard; Miles, James Edward;

    2016-01-01

    The objective of this review is to evaluate the existing literature with regard to the influence of propofol and remifentanil total intravenous anaesthesia (TIVA) on cerebral perfusion and oxygenation in healthy pigs. Anaesthesia has influence on cerebral haemodynamics and it is important not onl...

  6. Persistent resetting of the cerebral oxygen/glucose uptake ratio by brain activation

    DEFF Research Database (Denmark)

    Madsen, P L; Hasselbalch, S G; Hagemann, L P;

    1995-01-01

    fraction of the activation-induced excess glucose uptake. These data confirm earlier reports that brain activation can induce resetting of the cerebral oxygen/glucose consumption ratio, and indicate that the resetting persists for a long period after cerebral activation has been terminated and physiologic...

  7. Improved Quantification of Cerebral Vein Oxygenation Using Partial Volume Correction.

    Science.gov (United States)

    Ward, Phillip G D; Fan, Audrey P; Raniga, Parnesh; Barnes, David G; Dowe, David L; Ng, Amanda C L; Egan, Gary F

    2017-01-01

    Purpose: Quantitative susceptibility mapping (QSM) enables cerebral venous characterization and physiological measurements, such as oxygen extraction fraction (OEF). The exquisite sensitivity of QSM to deoxygenated blood makes it possible to image small veins; however partial volume effects must be addressed for accurate quantification. We present a new method, Iterative Cylindrical Fitting (ICF), to estimate voxel-based partial volume effects for susceptibility maps and use it to improve OEF quantification of small veins with diameters between 1.5 and 4 voxels. Materials and Methods: Simulated QSM maps were generated to assess the performance of the ICF method over a range of vein geometries with varying echo times and noise levels. The ICF method was also applied to in vivo human brain data to assess the feasibility and behavior of OEF measurements compared to the maximum intensity voxel (MIV) method. Results: Improved quantification of OEF measurements was achieved for vessels with contrast to noise greater than 3.0 and vein radii greater than 0.75 voxels. The ICF method produced improved quantitative accuracy of OEF measurement compared to the MIV approach (mean OEF error 7.7 vs. 12.4%). The ICF method provided estimates of vein radius (mean error partial volume maps (root mean-squared error partial volume estimates from the ICF method.

  8. High dose Erythropoietin increases Brain Tissue Oxygen Tension in Severe Vasospasm after Subarachnoid Hemorrhage

    Directory of Open Access Journals (Sweden)

    Helbok Raimund

    2012-06-01

    Full Text Available Abstract Background Vasospasm-related delayed cerebral ischemia (DCI significantly impacts on outcome after aneurysmal subarachnoid hemorrhage (SAH. Erythropoietin (EPO may reduce the severity of cerebral vasospasm and improve outcome, however, underlying mechanisms are incompletely understood. In this study, the authors aimed to investigate the effect of EPO on cerebral metabolism and brain tissue oxygen tension (PbtO2. Methods Seven consecutive poor grade SAH patients with multimodal neuromonitoring (MM received systemic EPO therapy (30.000 IU per day for 3 consecutive days for severe cerebral vasospasm. Cerebral perfusion pressure (CPP, mean arterial blood pressure (MAP, intracranial pressure (ICP, PbtO2 and brain metabolic changes were analyzed during the next 24 hours after each dose given. Statistical analysis was performed with a mixed effects model. Results A total of 22 interventions were analyzed. Median age was 47 years (32–68 and 86 % were female. Three patients (38 % developed DCI. MAP decreased 2 hours after intervention (P btO2 significantly increased over time (P  Conclusions EPO increases PbtO2 in poor grade SAH patients with severe cerebral vasospasm. The effect on outcome needs further investigation.

  9. Extracerebral Tissue Damage in the Intraluminal Filament Mouse Model of Middle Cerebral Artery Occlusion

    Science.gov (United States)

    Vaas, Markus; Ni, Ruiqing; Rudin, Markus; Kipar, Anja; Klohs, Jan

    2017-01-01

    Middle cerebral artery occlusion is the most common model of focal cerebral ischemia in the mouse. In the surgical procedure, the external carotid artery (ECA) is ligated; however, its effect on the tissue supplied by the vessel has not been described so far. C57BL/6 mice underwent 1 h of transient MCAO (tMCAO) or sham surgery. Multi-spectral optoacoustic tomography was employed at 30 min after surgery to assess oxygenation in the temporal muscles. Microstructural changes were assessed with magnetic resonance imaging and histological examination at 24 h and 48 h after surgery. Ligation of the ECA resulted in decreased oxygenation of the left temporal muscle in most sham-operated and tMCAO animals. Susceptible mice of both groups exhibited increased T2 relaxation times in the affected muscle with histological evidence of myofibre degeneration, interstitial edema, and neutrophil influx. Ligatures had induced an extensive neutrophil-dominated inflammatory response. ECA ligation leads to distinct hypoxic degenerative changes in the tissue of the ECA territory and to ligature-induced inflammatory processes. An impact on outcome needs to be considered in this stroke model. PMID:28348545

  10. Mapping of cerebral metabolic rate of oxygen using dynamic susceptibility contrast and blood oxygen level dependent MR imaging in acute ischemic stroke

    Energy Technology Data Exchange (ETDEWEB)

    Gersing, Alexandra S.; Schwaiger, Benedikt J. [Technical University Munich, Klinikum rechts der Isar, Department of Neuroradiology, Munich (Germany); University of California, Department of Radiology and Biomedical Imaging, San Francisco, CA (United States); Ankenbrank, Monika; Toth, Vivien; Bauer, Jan S.; Zimmer, Claus [Technical University Munich, Klinikum rechts der Isar, Department of Neuroradiology, Munich (Germany); Janssen, Insa [Technical University Munich, Department of Neurosurgery, Munich (Germany); Kooijman, Hendrik [Philips Healthcare, Hamburg (Germany); Wunderlich, Silke [Technical University Munich, Department of Neurology, Munich (Germany); Preibisch, Christine [Technical University Munich, Klinikum rechts der Isar, Department of Neuroradiology, Munich (Germany); Technical University Munich, Department of Neurology, Munich (Germany)

    2015-12-15

    MR-derived cerebral metabolic rate of oxygen utilization (CMRO{sub 2}) has been suggested to be analogous to PET-derived CMRO{sub 2} and therefore may be used for detection of viable tissue at risk for infarction. The purpose of this study was to evaluate MR-derived CMRO{sub 2} mapping in acute ischemic stroke in relation to established diffusion- and perfusion-weighted imaging. In 23 patients (mean age 63 ± 18.7 years, 11 women) with imaging findings for acute ischemic stroke, relative oxygen extraction fraction was calculated from quantitative transverse relaxation times (T2, T2*) and relative cerebral blood volume using a quantitative blood oxygenation level dependent (BOLD) approach in order to detect a local increase of deoxyhemoglobin. Relative CMRO{sub 2} (rCMRO{sub 2}) maps were calculated by multiplying relative oxygen extraction fraction (rOEF) by cerebral blood flow, derived from PWI. After co-registration, rCMRO{sub 2} maps were evaluated in comparison with apparent diffusion coefficient (ADC) and time-to-peak (TTP) maps. Mean rCMRO{sub 2} values in areas with diffusion-restriction or TTP/ADC mismatch were compared with rCMRO{sub 2} values in the contralateral tissue. In tissue with diffusion restriction, mean rCMRO{sub 2} values were significantly decreased compared to perfusion-impaired (17.9 [95 % confidence interval 10.3, 25.0] vs. 58.1 [95 % confidence interval 50.1, 70.3]; P < 0.001) and tissue in the contralateral hemisphere (68.2 [95 % confidence interval 61.4, 75.0]; P < 0.001). rCMRO{sub 2} in perfusion-impaired tissue showed no significant change compared to tissue in the contralateral hemisphere (58.1 [95 % confidence interval 50.1, 70.3] vs. 66.7 [95 % confidence interval 53.4, 73.4]; P = 0.34). MR-derived CMRO{sub 2} was decreased within diffusion-restricted tissue and stable within perfusion-impaired tissue, suggesting that this technique may be adequate to reveal different pathophysiological stages in acute stroke. (orig.)

  11. Cerebral blood flow and oxygenation in infants after birth asphyxia. Clinically useful information?

    DEFF Research Database (Denmark)

    Greisen, Gorm

    2014-01-01

    The term 'luxury perfusion' was coined nearly 50 years ago after observation of bright-red blood in the cerebral veins of adults with various brain pathologies. The bright-red blood represents decreased oxygen extraction and hence the perfusion is 'luxurious' compared to oxygen needs. Gradual loss...

  12. Quantifying the cerebral metabolic rate of oxygen by combining diffuse correlation spectroscopy and time-resolved near-infrared spectroscopy.

    Science.gov (United States)

    Verdecchia, Kyle; Diop, Mamadou; Lee, Ting-Yim; St Lawrence, Keith

    2013-02-01

    Preterm infants are highly susceptible to ischemic brain injury; consequently, continuous bedside monitoring to detect ischemia before irreversible damage occurs would improve patient outcome. In addition to monitoring cerebral blood flow (CBF), assessing the cerebral metabolic rate of oxygen (CMRO2) would be beneficial considering that metabolic thresholds can be used to evaluate tissue viability. The purpose of this study was to demonstrate that changes in absolute CMRO2 could be measured by combining diffuse correlation spectroscopy (DCS) with time-resolved near-infrared spectroscopy (TR-NIRS). Absolute CBF was determined using bolus-tracking TR-NIRS to calibrate the DCS measurements. Cerebral venous blood oxygenation (SvO2) was determined by multiwavelength TR-NIRS measurements, the accuracy of which was assessed by directly measuring the oxygenation of sagittal sinus blood. In eight newborn piglets, CMRO2 was manipulated by varying the anesthetics and by injecting sodium cyanide. No significant differences were found between the two sets of SvO2 measurements obtained by TR-NIRS or sagittal sinus blood samples and the corresponding CMRO2 measurements. Bland-Altman analysis showed a mean CMRO2 difference of 0.0268 ± 0.8340 mLO2/100 g/min between the two techniques over a range from 0.3 to 4 mL O2/100 g/min.

  13. Time-dependent changes in cerebral blood flow after acetazolamide loading into patients with hemodynamic cerebral ischemia. Relationship to cerebral oxygen metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Masakazu [Iwate Medical Univ., Morioka (Japan). School of Medicine

    2001-10-01

    The aim of this study was to clarify the relationship between time-dependent changes in cerebral blood flow (CBF) after acetazolamide loading and cerebral oxygen metabolism (CMRO{sub 2}). The subjects consisted of 30 patients with severe stenosis or occlusion of either internal carotid, middle cerebral, or vertebro-basilar artery. Regional CBF was measured at the resting state and 6, 16 and 30 minutes after intravenous administration of 1 gram of acetazolamide using the positron emission tomography in combination with the [{sup 15}O] H{sub 2}O bolus-injection method. Prior to CBF study, regional cerebral oxygen extraction fraction (OEF) was measured using the [{sup 15}O] O{sub 2} inhalation method. Regional CMRO{sub 2} was calculated based on CBF and OEF. According to the time-dependent changes in CBF responses to acetazolamide loading, the CBF responses are classified into good response type, paradoxical response type, and poor response type. Good response type (CBF increase rate more than 20% 6 minutes after acetazolamide loading), paradoxical response type (decrease of CBF 6 minutes after acetazolamide loading) and poor response type (CBF increase rate less than 20% 6 minutes after acetazolamide loading) were identified in 39, 11 and 10 areas, respectively. Brain areas with good response type showed normal OEF and normal CMRO{sub 2}. Brain areas with paradoxical response type showed increased OEF and normal CMRO{sub 2}. Brain areas with poor response type showed normal OEF and decreased CMRO{sub 2}. In view of these findings, the writer concludes that sequential measurement of cerebral blood flow (CBF) after acetazolamide loading enables one to know the regional cerebral oxygen metabolic state in patients with hemodynamic ischemia, and CBF should be measured at an early stage after the administration of acetazolamide to accurately detect misery perfusion. (author)

  14. Prone position is associated with mild cerebral oxygen desaturation in elderly surgical patients.

    Directory of Open Access Journals (Sweden)

    Stacie Deiner

    Full Text Available PURPOSE: A variety of hemodynamic and respiratory alterations accompany patients in the prone position; however the effect of the prone position on intraoperative cerebral saturation has not been studied. We sought to examine whether the incidence of cerebral oxygen desaturation in elderly patients (≥68 years of age undergoing spine surgery in the prone position was more common than patients undergoing major surgery in the supine position. METHODS: We performed a retrospective cohort study of 205 patients; 63 patients underwent surgery in the prone position and 142 in the supine position. Patients were evaluated for cerebral desaturation with bilateral cerebral oximetry. The primary predictor was position, secondary were: length of the surgery, incidence and duration of cerebral desaturation episodes at several thresholds, average time of Bispectral index below threshold of 45 in minutes, average electroencephalogram suppression ratio >0, amount of blood transfused, and the incidence of hypotension and hypertension. RESULTS: Elderly spine surgery patients in the prone position were more than twice as likely to experience mild cerebral desaturation as patients in the supine position. Patients in the prone position had longer surgeries; however cerebral desaturation in the prone position was significantly more common even when adjusted for surgery time and the occurrence of intraoperative hypotension. CONCLUSION: Cerebral desaturation is related to the prone position in elderly surgery patients. Future studies are necessary to determine whether this translates to a higher incidence of postoperative cognitive dysfunction and delirium.

  15. Blood flow and oxygenation changes due to low-frequency repetitive transcranial magnetic stimulation of the cerebral cortex

    Science.gov (United States)

    Mesquita, Rickson C.; Faseyitan, Olufunsho K.; Turkeltaub, Peter E.; Buckley, Erin M.; Thomas, Amy; Kim, Meeri N.; Durduran, Turgut; Greenberg, Joel H.; Detre, John A.; Yodh, Arjun G.; Hamilton, Roy H.

    2013-06-01

    Transcranial magnetic stimulation (TMS) modulates processing in the human brain and is therefore of interest as a treatment modality for neurologic conditions. During TMS administration, an electric current passing through a coil on the scalp creates a rapidly varying magnetic field that induces currents in the cerebral cortex. The effects of low-frequency (1 Hz), repetitive TMS (rTMS) on motor cortex cerebral blood flow (CBF) and tissue oxygenation in seven healthy adults, during/after 20 min stimulation, is reported. Noninvasive optical methods are employed: diffuse correlation spectroscopy (DCS) for blood flow and diffuse optical spectroscopy (DOS) for hemoglobin concentrations. A significant increase in median CBF (33%) on the side ipsilateral to stimulation was observed during rTMS and persisted after discontinuation. The measured hemodynamic parameter variations enabled computation of relative changes in cerebral metabolic rate of oxygen consumption during rTMS, which increased significantly (28%) in the stimulated hemisphere. By contrast, hemodynamic changes from baseline were not observed contralateral to rTMS administration (all parameters, p>0.29). In total, these findings provide new information about hemodynamic/metabolic responses to low-frequency rTMS and, importantly, demonstrate the feasibility of DCS/DOS for noninvasive monitoring of TMS-induced physiologic effects.

  16. Intraoperative transfusion threshold and tissue oxygenation

    DEFF Research Database (Denmark)

    Nielsen, K; Dahl, B; Johansson, P I;

    2012-01-01

    Transfusion with allogeneic red blood cells (RBCs) may be needed to maintain oxygen delivery during major surgery, but the appropriate haemoglobin (Hb) concentration threshold has not been well established. We hypothesised that a higher level of Hb would be associated with improved subcutaneous...

  17. Oxygen radical microscopy in living plant tissues

    DEFF Research Database (Denmark)

    Kristiansen, Kim Anker; Møller, Ian Max; Schulz, Alexander

    Reactive oxygen species (ROS) play a crucial role in a wide variety of processes. Initiation of many different cellular pathways, crosstalk between cells, developmental signalling in planta, programmed cell death and hypersensitive response in connection with plant-pathogen interactions are among...

  18. Aerobic fitness influences cerebral oxygenation response to maximal exercise in healthy subjects.

    Science.gov (United States)

    Oussaidene, Kahina; Prieur, Fabrice; Tagougui, Semah; Abaidia, Abdelbasset; Matran, Regis; Mucci, Patrick

    2015-01-01

    The study examined whether the aerobic fitness level modifies the cerebral oxygenation response to incremental ramp exercise, and more specifically the decline in cerebral oxygenation from heavy exercise up to maximal intensities. 11 untrained (VO2max 47.3±4.0 mL min(-1) kg(-1)) and 13 endurance-trained (VO2max 61.2±8.0 mL min(-1) kg(-1)) healthy men performed a maximal ramp cycle exercise. Left prefrontal cortex oxygenation (ΔHbO2) was monitored by near-infrared spectroscopy. A cerebral oxygenation threshold decline (ThCOx) during exercise was determined. ThCox occurred in all subjects but for higher VO2 (mL min(-1) kg(-1)) in endurance-trained than in untrained subjects (Pexercise intensity corresponding to ThCOx, ΔHbO2 was higher in endurance-trained than in untrained subjects (Pexercise intensities in endurance-trained in relation with their higher VO2max than untrained men. These results demonstrated that aerobic fitness influences cerebral oxygenation during exercise.

  19. Reduction in Cerebral Oxygenation due to Patent Ductus Arteriosus Is Pronounced in Small-for-Gestational-Age Neonates

    NARCIS (Netherlands)

    Cohen, Emily; Dix, Laura; Baerts, Willem; Alderliesten, Thomas; Lemmers, Petra; van Bel, Frank

    2016-01-01

    BACKGROUND: A haemodynamically significant patent ductus arteriosus (hsPDA) reduces cerebral oxygenation in appropriate-for-gestational-age (AGA) preterm neonates. Reduced cerebral oxygenation has been associated with brain injury. Preterm small-for-gestational-age (SGA) neonates show higher cerebra

  20. T2’-Imaging to Assess Cerebral Oxygen Extraction Fraction in Carotid Occlusive Disease: Influence of Cerebral Autoregulation and Cerebral Blood Volume

    Science.gov (United States)

    Deichmann, Ralf; Pfeilschifter, Waltraud; Hattingen, Elke; Singer, Oliver C.; Wagner, Marlies

    2016-01-01

    Purpose Quantitative T2'-mapping detects regional changes of the relation of oxygenated and deoxygenated hemoglobin (Hb) by using their different magnetic properties in gradient echo imaging and might therefore be a surrogate marker of increased oxygen extraction fraction (OEF) in cerebral hypoperfusion. Since elevations of cerebral blood volume (CBV) with consecutive accumulation of Hb might also increase the fraction of deoxygenated Hb and, through this, decrease the T2’-values in these patients we evaluated the relationship between T2’-values and CBV in patients with unilateral high-grade large-artery stenosis. Materials and Methods Data from 16 patients (13 male, 3 female; mean age 53 years) with unilateral symptomatic or asymptomatic high-grade internal carotid artery (ICA) or middle cerebral artery (MCA) stenosis/occlusion were analyzed. MRI included perfusion-weighted imaging and high-resolution T2’-mapping. Representative relative (r)CBV-values were analyzed in areas of decreased T2’ with different degrees of perfusion delay and compared to corresponding contralateral areas. Results No significant elevations in cerebral rCBV were detected within areas with significantly decreased T2’-values. In contrast, rCBV was significantly decreased (pperfusion delay and decreased T2’. Furthermore, no significant correlation between T2’- and rCBV-values was found. Conclusions rCBV is not significantly increased in areas of decreased T2’ and in areas of restricted perfusion in patients with unilateral high-grade stenosis. Therefore, T2’ should only be influenced by changes of oxygen metabolism, regarding our patient collective especially by an increase of the OEF. T2’-mapping is suitable to detect altered oxygen consumption in chronic cerebrovascular disease. PMID:27560515

  1. Alveolar gas exchange and tissue oxygenation during incremental treadmill exercise, and their associations with blood O(2) carrying capacity.

    Science.gov (United States)

    Rissanen, Antti-Pekka E; Tikkanen, Heikki O; Koponen, Anne S; Aho, Jyrki M; Hägglund, Harriet; Lindholm, Harri; Peltonen, Juha E

    2012-01-01

    The magnitude and timing of oxygenation responses in highly active leg muscle, less active arm muscle, and cerebral tissue, have not been studied with simultaneous alveolar gas exchange measurement during incremental treadmill exercise. Nor is it known, if blood O(2) carrying capacity affects the tissue-specific oxygenation responses. Thus, we investigated alveolar gas exchange and tissue (m. vastus lateralis, m. biceps brachii, cerebral cortex) oxygenation during incremental treadmill exercise until volitional fatigue, and their associations with blood O(2) carrying capacity in 22 healthy men. Alveolar gas exchange was measured, and near-infrared spectroscopy (NIRS) was used to monitor relative concentration changes in oxy- (Δ[O(2)Hb]), deoxy- (Δ[HHb]) and total hemoglobin (Δ[tHb]), and tissue saturation index (TSI). NIRS inflection points (NIP), reflecting changes in tissue-specific oxygenation, were determined and their coincidence with ventilatory thresholds [anaerobic threshold (AT), respiratory compensation point (RC); V-slope method] was examined. Blood O(2) carrying capacity [total hemoglobin mass (tHb-mass)] was determined with the CO-rebreathing method. In all tissues, NIPs coincided with AT, whereas RC was followed by NIPs. High tHb-mass associated with leg muscle deoxygenation at peak exercise (e.g., Δ[HHb] from baseline walking to peak exercise vs. tHb-mass: r = 0.64, p capacity for blood O(2) carrying was associated with a high level of m. vastus lateralis deoxygenation at peak exercise.

  2. Cerebral blood flow, oxygen and glucose metabolism with PET in progressive supranuclear palsy

    Energy Technology Data Exchange (ETDEWEB)

    Otsuka, Makoto; Ichiya, Yuici; Kuwabara, Yasuo (Kyushu Univ., Fukuoka (Japan). Faculty of Medicine) (and others)

    1989-11-01

    Cerebral blood flow, cerebral oxygen metabolic rate and cerebral glucose metabolic rate were measured with positron emission tomography (PET) in four patients with progressive supranuclear palsy (PSP). Decreased blood flow and hypometabolism of oxygen and glucose were found in both subcortical and cortical regions, particularly in the striatum including the head of the caudate nucleus and the frontal cortex. The coupling between blood flow and metabolism was preserved even in the regions which showed decreased blood flow and hypometabolism. These findings indicated the hypofunction, as revealed by decreased blood flow and hypometablolism on PET, both in the striatum and the frontal cortex, and which may underlie the pathophysiological mechanism of motor and mental disturbance in PSP. (author).

  3. Effect of propofol and remifentanil on cerebral perfusion and oxygenation in pigs

    DEFF Research Database (Denmark)

    Mikkelsen, Mai Louise Grandsgaard; Ambrus, Rikard; Miles, James Edward

    2016-01-01

    in human but also in veterinary anaesthesia to preserve optimal regulation of cerebral haemodynamics. Propofol and remifentanil are widely used in neuroanaesthesia and are increasingly used in experimental animal studies. In translational models, the pig has advantages compared to small laboratory animals......The objective of this review is to evaluate the existing literature with regard to the influence of propofol and remifentanil total intravenous anaesthesia (TIVA) on cerebral perfusion and oxygenation in healthy pigs. Anaesthesia has influence on cerebral haemodynamics and it is important not only...... and oxygenation (CPO). The evidence evaluated in this systematic review is limited, not focused on propofol and remifentanil and possibly influenced by factors of potential importance for CPO assessment. In one study of healthy pigs, CPO measures were within normal ranges following propofol...

  4. Impaired cerebral blood flow and oxygenation during exercise in type 2 diabetic patients

    DEFF Research Database (Denmark)

    Kim, Yu-Sok; Seifert, Thomas; Brassard, Patrice

    2015-01-01

    Endothelial vascular function and capacity to increase cardiac output during exercise are impaired in patients with type 2 diabetes (T2DM). We tested the hypothesis that the increase in cerebral blood flow (CBF) during exercise is also blunted and, therefore, that cerebral oxygenation becomes...... affected and perceived exertion increased in T2DM patients. We quantified cerebrovascular besides systemic hemodynamic responses to incremental ergometer cycling exercise in eight male T2DM and seven control subjects. CBF was assessed from the Fick equation and by transcranial Doppler-determined middle...... at higher workloads in T2DM patients and their work capacity and increase in cardiac output were only ~80% of that established in the control subjects. CBF and cerebral oxygenation were reduced during exercise in T2DM patients (P

  5. Systematic review of near-infrared spectroscopy determined cerebral oxygenation during non-cardiac surgery

    DEFF Research Database (Denmark)

    Nielsen, Henning B

    2014-01-01

    Near-infrared spectroscopy (NIRS) is used to monitor regional cerebral oxygenation (rScO2) during cardiac surgery but is less established during non-cardiac surgery. This systematic review aimed (i) to determine the non-cardiac surgical procedures that provoke a reduction in rScO2 and (ii...

  6. Effects of midazolam and morphine on cerebral oxygenation and hemodynamics in ventilated premature infants.

    NARCIS (Netherlands)

    Velden, A.A.E.M. van der; Hopman, J.C.W.; Klaessens, J.H.G.M.; Feuth, A.B.; Sengers, R.C.A.; Liem, K.D.

    2006-01-01

    BACKGROUND: Midazolam sedation and morphine analgesia are commonly used in ventilated premature infants. OBJECTIVES: To evaluate the effects of midazolam versus morphine infusion on cerebral oxygenation and hemodynamics in ventilated premature infants. METHODS: 11 patients (GA 26.6-33.0 weeks, BW 78

  7. A method for monitoring of oxygen saturation changes in brain tissue using diffuse reflectance spectroscopy.

    Science.gov (United States)

    Rejmstad, Peter; Johansson, Johannes D; Haj-Hosseini, Neda; Wårdell, Karin

    2017-03-01

    Continuous measurement of local brain oxygen saturation (SO2 ) can be used to monitor the status of brain trauma patients in the neurocritical care unit. Currently, micro-oxygen-electrodes are considered as the "gold standard" in measuring cerebral oxygen pressure (pO2 ), which is closely related to SO2 through the oxygen dissociation curve (ODC) of hemoglobin, but with the drawback of slow in response time. The present study suggests estimation of SO2 in brain tissue using diffuse reflectance spectroscopy (DRS) for finding an analytical relation between measured spectra and the SO2 for different blood concentrations. The P3 diffusion approximation is used to generate a set of spectra simulating brain tissue for various levels of blood concentrations in order to estimate SO2 . The algorithm is evaluated on optical phantoms mimicking white brain matter (blood volume of 0.5-2%) where pO2 and temperature is controlled and on clinical data collected during brain surgery. The suggested method is capable of estimating the blood fraction and oxygen saturation changes from the spectroscopic signal and the hemoglobin absorption profile.

  8. Reduced Cerebral Oxygen Content in the DG and SVZ In Situ Promotes Neurogenesis in the Adult Rat Brain In Vivo.

    Directory of Open Access Journals (Sweden)

    Kuan Zhang

    Full Text Available Neurogenesis in the adult brain occurs mainly within two neurogenic structures, the dentate gyrus (DG of the hippocampus and the sub-ventricular zone (SVZ of the forebrain. It has been reported that mild hypoxia promoted the proliferation of Neural Stem Cells (NSCsin vitro. Our previous study further demonstrated that an external hypoxic environment stimulated neurogenesis in the adult rat brain in vivo. However, it remains unknown how external hypoxic environments affect the oxygen content in the brain and result in neurogenesis. Here we use an optical fiber luminescent oxygen sensor to detect the oxygen content in the adult rat brain in situ under normoxia and hypoxia. We found that the distribution of oxygen in cerebral regions is spatiotemporally heterogeneous. The Po2 values in the ventricles (45∼50 Torr and DG (approximately 10 Torr were much higher than those of other parts of the brain, such as the cortex and thalamus (approximately 2 Torr. Interestingly, our in vivo studies showed that an external hypoxic environment could change the intrinsic oxygen content in brain tissues, notably reducing oxygen levels in both the DG and SVZ, the major sites of adult neurogenesis. Furthermore, the hypoxic environment also increased the expression of HIF-1α and VEGF, two factors that have been reported to regulate neurogenesis, within the DG and SVZ. Thus, we have demonstrated that reducing the oxygen content of the external environment decreased Po2 levels in the DG and SVZ. This reduced oxygen level in the DG and SVZ might be the main mechanism triggering neurogenesis in the adult brain. More importantly, we speculate that varying oxygen levels may be the physiological basis of the regionally restricted neurogenesis in the adult brain.

  9. Reduced Cerebral Oxygen Content in the DG and SVZ In Situ Promotes Neurogenesis in the Adult Rat Brain In Vivo.

    Science.gov (United States)

    Zhang, Kuan; Zhou, Yanzhao; Zhao, Tong; Wu, Liying; Huang, Xin; Wu, Kuiwu; Xu, Lun; Li, Dahu; Liu, Shuhong; Zhao, Yongqi; Fan, Ming; Zhu, Lingling

    2015-01-01

    Neurogenesis in the adult brain occurs mainly within two neurogenic structures, the dentate gyrus (DG) of the hippocampus and the sub-ventricular zone (SVZ) of the forebrain. It has been reported that mild hypoxia promoted the proliferation of Neural Stem Cells (NSCs)in vitro. Our previous study further demonstrated that an external hypoxic environment stimulated neurogenesis in the adult rat brain in vivo. However, it remains unknown how external hypoxic environments affect the oxygen content in the brain and result in neurogenesis. Here we use an optical fiber luminescent oxygen sensor to detect the oxygen content in the adult rat brain in situ under normoxia and hypoxia. We found that the distribution of oxygen in cerebral regions is spatiotemporally heterogeneous. The Po2 values in the ventricles (45∼50 Torr) and DG (approximately 10 Torr) were much higher than those of other parts of the brain, such as the cortex and thalamus (approximately 2 Torr). Interestingly, our in vivo studies showed that an external hypoxic environment could change the intrinsic oxygen content in brain tissues, notably reducing oxygen levels in both the DG and SVZ, the major sites of adult neurogenesis. Furthermore, the hypoxic environment also increased the expression of HIF-1α and VEGF, two factors that have been reported to regulate neurogenesis, within the DG and SVZ. Thus, we have demonstrated that reducing the oxygen content of the external environment decreased Po2 levels in the DG and SVZ. This reduced oxygen level in the DG and SVZ might be the main mechanism triggering neurogenesis in the adult brain. More importantly, we speculate that varying oxygen levels may be the physiological basis of the regionally restricted neurogenesis in the adult brain.

  10. Effect of head rotation during surgery in the prone position on regional cerebral oxygen saturation

    DEFF Research Database (Denmark)

    Andersen, Johnny Dohn Holmgren; Baake, Gerben; Wiis, Julie Therese;

    2014-01-01

    BACKGROUND: Near-infrared spectroscopy (NIRS) has been used to study regional cerebral blood oxygen saturation (rScO2) in patients in the prone position. OBJECTIVES: We aimed to test the hypothesis that head rotation more than 45° would affect the rScO2. DESIGN: A prospective, controlled, single......-state anaesthesia with the head in the neutral position, rotated left, rotated right and returned to the neutral position. Each series consisted of three measurements: resting on the head support, during head lift (to relieve pressure on the tissue at the sensors) and returned to rest on the head support. MAIN...... OUTCOME MEASURES: The differences in rScO2 between the neutral and the turned head positions. RESULTS: For both left and right sensors, the median differences in rScO2 between neutral and left or right positions were between 0 and -1 with the head up (P = 0.14 to 0.84). The median differences...

  11. Optimal concentration and time window for proliferation and differentiation of neural stem cells from embryonic cerebral cortex:5% oxygen preconditioning for 72 hours

    Institute of Scientific and Technical Information of China (English)

    Li-li Yuan; Ying-jun Guan; Deng-dian Ma; Hong-mei Du

    2015-01-01

    Hypoxia promotes proliferation and differentiation of neural stem cells from embryonic day 12 rat brain tissue, but the concentration and time of hypoxic preconditioning are controversial. To address this, we cultured neural stem cells isolated from embryonic day 14 rat cerebral cortex in 5% and 10% oxygenin vitro. MTT assay, neurosphere number, and immunolfuorescent staining found that 5% or 10% oxygen preconditioning for 72 hours improved neural stem cell viability and proliferation. With prolonged hypoxic duration (120 hours), the proportion of apoptotic cells increased. Thus, 5% oxygen preconditioning for 72 hours promotes neural stem cell prolif-eration and neuronal differentiation. Our ifndings indicate that the optimal concentration and duration of hypoxic preconditioning for promoting proliferation and differentiation of neural stem cells from the cerebral cortex are 5% oxygen for 72 hours.

  12. Quantitative measurement of cerebral oxygen extraction fraction using MRI in patients with MELAS.

    Directory of Open Access Journals (Sweden)

    Lei Yu

    Full Text Available OBJECTIVE: To quantify the cerebral OEF at different phases of stroke-like episodes in patients with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS by using MRI. METHODS: We recruited 32 patients with MELAS confirmed by gene analysis. Conventional MRI scanning, as well as functional MRI including arterial spin labeling and oxygen extraction fraction imaging, was undertaken to obtain the pathological and metabolic information of the brains at different stages of stroke-like episodes in patients. A total of 16 MRI examinations at the acute and subacute phase and 19 examinations at the interictal phase were performed. In addition, 24 healthy volunteers were recruited for control subjects. Six regions of interest were placed in the anterior, middle, and posterior parts of the bilateral hemispheres to measure the OEF of the brain or the lesions. RESULTS: OEF was reduced significantly in brains of patients at both the acute and subacute phase (0.266 ± 0.026 and at the interictal phase (0.295 ± 0.009, compared with normal controls (0.316 ± 0.025. In the brains at the acute and subacute phase of the episode, 13 ROIs were prescribed on the stroke-like lesions, which showed decreased OEF compared with the contralateral spared brain regions. Increased blood flow was revealed in the stroke-like lesions at the acute and subacute phase, which was confined to the lesions. CONCLUSION: MRI can quantitatively show changes in OEF at different phases of stroke-like episodes. The utilization of oxygen in the brain seems to be reduced more severely after the onset of episodes in MELAS, especially for those brain tissues involved in the episodes.

  13. Hepatic encephalopathy is associated with decreased cerebral oxygen metabolism and blood flow, not increased ammonia uptake

    DEFF Research Database (Denmark)

    Dam, Gitte; Keiding, Susanne; Munk, Ole L

    2013-01-01

    Studies have shown decreased cerebral oxygen metabolism (CMRO(2)) and blood flow (CBF) in patients with cirrhosis with hepatic encephalopathy (HE). It remains unclear, however, whether these disturbances are associated with HE or with cirrhosis itself and how they may relate to arterial blood...... ammonia concentration and cerebral metabolic rate of blood ammonia (CMRA). We addressed these questions in a paired study design by investigating patients with cirrhosis during and after recovery from an acute episode of HE type C. CMRO(2), CBF, and CMRA were measured by dynamic positron emission...

  14. Cerebral perfusion, oxygenation and metabolism during exercise in young and elderly individuals

    DEFF Research Database (Denmark)

    Fisher, James P; Hartwich, Doreen; Seifert, Thomas

    2013-01-01

    artery blood velocity (MCA V(mean)), mean arterial pressure (MAP), cardiac output (CO) and the partial pressure of arterial carbon dioxide (PaCO(2)) were measured. Blood samples were obtained from the right internal jugular vein and brachial artery to determine concentration differences for oxygen (O(2......)), glucose and lactate across the brain. The molar ratio between the cerebral uptake of O(2) versus carbohydrate (O(2)-carbohydrate index; O(2) / [glucose + 0.5 lactate]; OCI), the cerebral metabolic rate of O(2) (CMRO(2)) and changes in mitochondrial O(2) tension (P(mito)O(2)) were calculated. W...

  15. Influence of intranasal and carotid cooling on cerebral temperature balance and oxygenation

    Directory of Open Access Journals (Sweden)

    Lars eNybo

    2014-02-01

    Full Text Available The present study evaluated the influence of intranasal cooling with balloon catheters, increased nasal ventilation, or percutaneous cooling of the carotid arteries on cerebral temperature balance and oxygenation in six healthy male subjects. Aortic arch and internal jugular venous blood temperatures were measured to assess the cerebral heat balance and corresponding paired blood samples were obtained to evaluate cerebral metabolism and oxygenation at rest, following 60 min of intranasal cooling, 5 min of nasal ventilation, and 15 min with carotid cooling. Intranasal cooling induced a parallel drop in jugular venous and arterial blood temperatures by 0.30 ± 0.08 ºC (mean ± SD, whereas nasal ventilation and carotid cooling failed to lower the jugular venous blood temperature. The magnitude of the arterio-venous temperature difference across the brain remained unchanged at - 0.33 ± 0.05 ºC following intranasal and carotid cooling, but increased to - 0.44 ± 0.11 ºC (P< 0.05 following nasal ventilation. Calculated cerebral capillary oxygen tension was 43 ± 3 mmHg at rest and remained unchanged during intranasal and carotid cooling, but decreased to 38 ± 2 mmHg (P< 0.05 following increased nasal ventilation. In conclusion, percutaneous cooling of the carotid arteries and intranasal cooling with balloon catheters are insufficient to influence cerebral oxygenation in normothermic subjects as the cooling rate is only 0.3 ºC per hour and neither intranasal nor carotid cooling is capable of inducing selective brain cooling.

  16. The role of blood flow distribution in the regulation of cerebral oxygen availability in fetal growth restriction.

    Science.gov (United States)

    Luria, Oded; Bar, Jacob; Kovo, Michal; Malinger, Gustavo; Golan, Abraham; Barnea, Ofer

    2012-04-01

    Fetal growth restriction (FGR) elicits hemodynamic compensatory mechanisms in the fetal circulation. These mechanisms are complex and their effect on the cerebral oxygen availability is not fully understood. To quantify the contribution of each compensatory mechanism to the fetal cerebral oxygen availability, a mathematical model of the fetal circulation was developed. The model was based on cardiac-output distribution in the fetal circulation. The compensatory mechanisms of FGR were simulated and their effects on cerebral oxygen availability were analyzed. The mathematical analysis included the effects of cerebral vasodilation, placental resistance to blood flow, degree of blood shunting by the ductus venosus and the effect of maternal-originated placental insufficiency. The model indicated a unimodal dependency between placental blood flow and cerebral oxygen availability. Optimal cerebral oxygen availability was achieved when the placental blood flow was mildly reduced compared to the normal flow. This optimal ratio was found to increase as the hypoxic state of FGR worsens. The model indicated that cerebral oxygen availability is increasingly dependent on the cardiac output distribution as the fetus gains weight.

  17. Systematic review of near-infrared spectroscopy determined cerebral oxygenation during non-cardiac surgery

    Directory of Open Access Journals (Sweden)

    Henning Bay Nielsen

    2014-03-01

    Full Text Available Near-infrared spectroscopy (NIRS is used to monitor regional cerebral oxygenation (rScO2 during cardiac surgery but is less established during non-cardiac surgery. This systematic review aimed i to determine the non-cardiac surgical procedures that provoke a reduction in rScO2 and ii to evaluate whether an intraoperative reduction in rScO2 influences postoperative outcome. The PubMed and Embase database were searched from inception until April 30, 2013 and inclusion criteria were intraoperative NIRS determined rScO2 in adult patients undergoing non-cardiac surgery. The type of surgery and number of patients included were recorded. There was included 113 articles and evidence suggests that rScO2 is reduced during thoracic surgery involving single lung ventilation, major abdominal surgery, hip surgery, and laparascopic surgery with the patient placed in anti-Tredelenburg’s position. Shoulder arthroscopy in the beach chair and carotid endarterectomy with clamped internal carotid artery also cause pronounced cerebral desaturation. A >20% reduction in rScO2 coincides with indices of regional and global cerebral ischemia during carotid endarterectomy. Following thoracic surgery, major orthopedic and abdominal surgery the occurrence of postoperative cognitive dysfunction might be related to intraoperative cerebral desaturation. In conclusion, certain non-cardiac surgical procedures is associated with an increased risk for the occurrence of regional cerebral oxygenation. Evidence for an association between cerebral desaturation and postoperative outcome parameters other than cognitive dysfunction needs to be established.

  18. New Molecular Knowledge Towards the Trigemino-Cardiac Reflex as a Cerebral Oxygen-Conserving Reflex

    Directory of Open Access Journals (Sweden)

    N. Sandu

    2010-01-01

    Full Text Available The trigemino-cardiac reflex (TCR represents the most powerful of the autonomous reflexes and is a subphenomenon in the group of the so-called “oxygen-conserving reflexes”. Within seconds after the initiation of such a reflex, there is a powerful and differentiated activation of the sympathetic system with subsequent elevation in regional cerebral blood flow (CBF, with no changes in the cerebral metabolic rate of oxygen (CMRO2 or in the cerebral metabolic rate of glucose (CMRglc. Such an increase in regional CBF without a change of CMRO2 or CMRglc provides the brain with oxygen rapidly and efficiently. Features of the reflex have been discovered during skull base surgery, mediating reflex protection projects via currently undefined pathways from the rostral ventrolateral medulla oblongata to the upper brainstem and/or thalamus, which finally engage a small population of neurons in the cortex. This cortical center appears to be dedicated to transduce a neuronal signal reflexively into cerebral vasodilatation and synchronization of electrocortical activity; a fact that seems to be unique among autonomous reflexes. Sympathetic excitation is mediated by cortical-spinal projection to spinal preganglionic sympathetic neurons, whereas bradycardia is mediated via projections to cardiovagal motor medullary neurons. The integrated reflex response serves to redistribute blood from viscera to the brain in response to a challenge to cerebral metabolism, but seems also to initiate a preconditioning mechanism. Previous studies showed a great variability in the human TCR response, in special to external stimuli and individual factors. The TCR gives, therefore, not only new insights into novel therapeutic options for a range of disorders characterized by neuronal death, but also into the cortical and molecular organization of the brain.

  19. New molecular knowledge towards the trigemino-cardiac reflex as a cerebral oxygen-conserving reflex.

    Science.gov (United States)

    Sandu, N; Spiriev, T; Lemaitre, F; Filis, A; Schaller, B

    2010-05-04

    The trigemino-cardiac reflex (TCR) represents the most powerful of the autonomous reflexes and is a subphenomenon in the group of the so-called "oxygen-conserving reflexes". Within seconds after the initiation of such a reflex, there is a powerful and differentiated activation of the sympathetic system with subsequent elevation in regional cerebral blood flow (CBF), with no changes in the cerebral metabolic rate of oxygen (CMRO2) or in the cerebral metabolic rate of glucose (CMRglc). Such an increase in regional CBF without a change of CMRO2 or CMRglc provides the brain with oxygen rapidly and efficiently. Features of the reflex have been discovered during skull base surgery, mediating reflex protection projects via currently undefined pathways from the rostral ventrolateral medulla oblongata to the upper brainstem and/or thalamus, which finally engage a small population of neurons in the cortex. This cortical center appears to be dedicated to transduce a neuronal signal reflexively into cerebral vasodilatation and synchronization of electrocortical activity; a fact that seems to be unique among autonomous reflexes. Sympathetic excitation is mediated by cortical-spinal projection to spinal preganglionic sympathetic neurons, whereas bradycardia is mediated via projections to cardiovagal motor medullary neurons. The integrated reflex response serves to redistribute blood from viscera to the brain in response to a challenge to cerebral metabolism, but seems also to initiate a preconditioning mechanism. Previous studies showed a great variability in the human TCR response, in special to external stimuli and individual factors. The TCR gives, therefore, not only new insights into novel therapeutic options for a range of disorders characterized by neuronal death, but also into the cortical and molecular organization of the brain.

  20. PET imaging of cerebral perfusion and oxygen metabolism in stroke

    Energy Technology Data Exchange (ETDEWEB)

    Pointon, O.; Yasaka, M.; Berlangieri, S.U.; Newton, M.R.; Thomas, D.L.; Chan, C.G.; Egan, G.F.; Tochon-Danguy, H.J.; O``Keefe, G.; Donnan, G.A.; McKay, W.J. [Austin Hospital, Melbourne, VIC (Australia). Centre for PET and Depts of Nuclear Medicine and Neurology

    1998-03-01

    Full text: Stroke remains a devastating clinical event with few therapeutic options. In patients with acute stroke, we studied the cerebral perfusion and metabolic patterns with {sup 15}O-CO{sub 2} or H{sub 2}O and {sup 15}O-O{sub 2} positron emission tomography and correlated these findings to the clinical background. Forty three patients underwent 45 studies 0-23 days post-stroke (mean 7 days). Fifteen patients showed luxury perfusion (Group A), 10 had matched low perfusion and metabolism (B) and 3 showed mixed pattern including an area of misery perfusion (C). Seventeen showed no relevant abnormality (D) and there were no examples of isolated misery perfusion. Twelve of the 15 in Group A had either haemorrhagic transformation on CT, re-opening on angiography, or a cardioembolic mechanism. In contrast only 5/10 in Group B, 0/3 in Group C and 2/17 in Group D had these features. Although 7/10 in group B had moderate or large size infarcts on CT the incidence of haemorrhagic transformation was low (2/10) and significant carotid stenoses were more common in those studied (5/8) compared with the other groups. Misery perfusion was not seen beyond five days. Thus, luxury perfusion seems to be related to a cardio-embolic mechanism or reperfusion. Matched low perfusion and metabolism was associated with a low rate of haemorrhagic transformation despite a high incidence of moderate to large size infarcts. Misery perfusion is an early phenomenon in the evolution of ischaemic stroke.

  1. Changes in cerebral blood oxygenation induced by active standing test in children with POTS and NMS.

    Science.gov (United States)

    Endo, Ayumi; Fujita, Yukihiko; Fuchigami, Tatsuo; Takahashi, Shori; Mugishima, Hideo; Skatani, Kaoru

    2014-01-01

    Orthostatic dysregulation (OD) has been classified into subtypes by heart rate and blood pressure; however, the hemodynamics of brains have not yet been revealed. Therefore, we investigated changes in cerebral blood flow and oxygenation during an active standing test to clarify the pathophysiology of two subtypes: postural tachycardia syndrome (POTS) and neurally mediated syncope (NMS). We studied 31 children (15 boys, 16 girls; mean age, 14.0 ± 1.7 years) who presented with OD at the Department of Pediatrics and Child Health, Nihon University School of Medicine between 2009 and 2011. OD was diagnosed using the Japanese clinical guidelines for juvenile orthostatic dysregulation. After a 10-min resting period in the supine position, patients were asked to quickly stand up and keep upright for 10 min. Cerebral blood flow and cerebral oxygenation were measured using transcranial Doppler sonography and near-infrared spectroscopy. POTS showed a significant decrease of oxy-Hb and resistance index (RI), suggesting transient ischemia with maintainable cerebral autoregulation. NMS showed a decrease of oxy-Hb and an increase of RI, suggesting ischemia and impairment of autoregulation.

  2. Effects of autoregulation and CO2 reactivity on cerebral oxygen transport.

    Science.gov (United States)

    Payne, S J; Selb, J; Boas, D A

    2009-11-01

    Both autoregulation and CO(2) reactivity are known to have significant effects on cerebral blood flow and thus on the transport of oxygen through the vasculature. In this paper, a previous model of the autoregulation of blood flow in the cerebral vasculature is expanded to include the dynamic behavior of oxygen transport through binding with hemoglobin. The model is used to predict the transfer functions for both oxyhemoglobin and deoxyhemoglobin in response to fluctuations in arterial blood pressure and arterial CO(2) concentration. It is shown that only six additional nondimensional groups are required in addition to the five that were previously found to characterize the cerebral blood flow response. A resonant frequency in the pressure-oxyhemoglobin transfer function is found to occur in the region of 0.1 Hz, which is a frequency of considerable physiological interest. The model predictions are compared with results from the published literature of phase angle at this frequency, showing that the effects of changes in breathing rate can significantly alter the inferred phase dynamics between blood pressure and hemoglobin. The question of whether dynamic cerebral autoregulation is affected under conditions of stenosis or stroke is then examined.

  3. The Impact of Vasoactive Drugs on Oxygenation and Tissue Perfusion

    Science.gov (United States)

    1992-01-01

    useful in the management of congestive heart failure, cardiogenic pulmonary edema , mitral or aortic regurgitation and persistent chest pain...administration include refractory cardiac failure, cardiogenic shock, septic shock, post cardiac surgery, and acute renal failure (Opie, 1991; Budnv... cardiogenic , anaphylactic, and septic shock, and cardiac arrest (Zaritsky & Eisenberg, 1986). Affect on Oxygenation and Tissue Perfusion Epinephrine, as with

  4. Closed versus open endotracheal suctioning in preterm infants: effects on cerebral oxygenation and blood volume.

    Science.gov (United States)

    Mosca, F A; Colnaghi, M; Lattanzio, M; Bray, M; Pugliese, S; Fumagalli, M

    1997-01-01

    The aim of our study was to compare, using near-infrared spectroscopy (NIRS), the effects on cerebral intracellular oxygenation and cerebral blood volume (CBV) of closed endotracheal suctioning (CS), which permits continuous ventilation of the patient, with open endotracheal suctioning (OS), which requires disconnection from the ventilator. Eleven preterm infants were studied. Each patient underwent one CS, followed, after 60 min, by one OS, or vice versa, three times during the same day. Modifications in CBV and oxidized cytochrome oxidase (CytO2) were continuously detected by NIRS; arterial oxygen saturation (SaO2) heart rate (HR), transcutaneous carbon dioxide tension and mean arterial blood pressure were simultaneously recorded. Significant reductions in HR and SaO2 were observed following OS; the magnitude and duration of these negative effects of suctioning were significantly reduced with CS. In addition, the decrease in CBV was more pronounced than following CS. No changes in CytO2 concentration were seen.

  5. Is cerebral oxygenation negatively affected by infusion of norepinephrine in healthy subjects?

    DEFF Research Database (Denmark)

    Brassard, P.; Seifert, T.; Secher, Niels H.

    2009-01-01

    BACKGROUND: Vasopressor agents are commonly used to increase mean arterial pressure (MAP) in order to secure a pressure gradient to perfuse vital organs. The influence of norepinephrine on cerebral oxygenation is not clear. The aim of this study was to evaluate the impact of the infusion of norep......BACKGROUND: Vasopressor agents are commonly used to increase mean arterial pressure (MAP) in order to secure a pressure gradient to perfuse vital organs. The influence of norepinephrine on cerebral oxygenation is not clear. The aim of this study was to evaluate the impact of the infusion...... infused at 0.1 microg kg(-1) min(-1) [Sc(O2): 78 (75-94) to 69 (61-83)%; P cm s(-1); P

  6. Maternal antihypertensive drugs may influence cerebral oxygen extraction in preterm infants during the first days after birth

    NARCIS (Netherlands)

    Verhagen, Elise A.; Kooi, Elisabeth M. W.; van den Berg, Paul P.; Bos, Arend F.

    2013-01-01

    Objective: To determine whether maternal antihypertensive drugs influenced cerebral oxygenation in preterm infants during the first days after birth. Methods: We included 49 preterm infants (median gestational age 30.3 weeks, (range 26.0-31.9), birth weight 1250 g (560-2250)). Regional cerebral oxyg

  7. Lung vital capacity and oxygen saturation in adults with cerebral palsy

    Directory of Open Access Journals (Sweden)

    Lampe R

    2014-12-01

    Full Text Available Renée Lampe,1,2 Tobias Blumenstein,2 Varvara Turova,2 Ana Alves-Pinto2 1Markus Würth Stiftungsprofessur, Technical University of Munich, Munich, Germany; 2Research Unit for Cerebral Palsy and Children Neuroorthopaedics of the Buhl-Strohmaier Foundation, Orthopedic Department of the Clinic “rechts der Isar” of the Technical University of Munich, Munich, Germany Background: Individuals with infantile cerebral palsy have multiple disabilities. The most conspicuous syndrome being investigated from many aspects is motor movement disorder with a spastic gait pattern. The lung function of adults with spasticity attracts less attention in the literature. This is surprising because decreased thoracic mobility and longstanding scoliosis should have an impact on lung function. With increasing age and the level of disability, individuals become susceptible to lung infections and reflux illness, and these are accompanied by increased aspiration risk. This study examined, with different methods, to what extent adults with congenital cerebral palsy and acquired spastic paresis – following traumatic brain injury – showed restriction of lung function. It also assessed the contribution of disability level on this restriction.Methods: The oxygen saturation of 46 adults with a diagnosis of cerebral palsy was measured with an oximeter. Lung vital capacity was measured with a mobile spirometer and excursion of the thorax was clinically registered. The gross motor function levels and the presence or absence of scoliosis were determined.Results: A significantly positive correlation between lung vital capacity and chest expansion was established. Both the lung vital capacity and the thorax excursion decreased with increases in gross motor function level. Oxygen saturation remained within the normal range in all persons, in spite of reduced values of the measured lung parameters. No statistically significant dependency between lung vital capacity and oxygen

  8. Hyperbaric oxygen combined with drug therapy in the treatment of acute cerebral infarction clinical analysis

    Institute of Scientific and Technical Information of China (English)

    Wen-Cui Lin; Kang Lin; Jing Wang; Shuai Li

    2015-01-01

    Objective:To explore the effects of hyperbaric oxygen combined with edaravone, salviae miltiorrhizae and ligustrazine and sodium ozagrel in the treatment of acute cerebral infarction clinical analysis.Methods: A total of 200 cases of acute cerebral infraction patients were randomly divided into observation group and control group. The control group was treated with edaravone, salvia miltiorrhizae and ligustrazine and sodium ozagrel; on the basis of treatment in control group, the observation group was combined with hyperbaric oxygen therapy. The neurological deficit scores were observed before and after treatment in patients of two groups, meanwhile the activities of daily living (ADL) and clinical effects were compared.Results: The total effective rate in observation group (92%) was significantly higher than control group (79%), the differences were statistically significant; the score of ADL in observation group after treatment was obviously higher than control group [(79.91±5.16)vs (61.62±5.60)], and the differences were statistically significant. The neurological deficit scores after treatment were obviously lower than the control group [(9.55±4.13)vs (15.46±4.92)], the differences were statistically significant.Conclusion: Hyperbaric oxygen combined with edaravone, salvia miltiorrhizae and ligustrazine and sodium ozagrel in the treatment of acute cerebral infarction can improve the symptoms of microcirculation and neurologic impairment, and improve the patient s quality of life.

  9. Erythrocytes Are Oxygen-Sensing Regulators of the Cerebral Microcirculation

    DEFF Research Database (Denmark)

    Wei, Helen Shinru; Kang, Hongyi; Rasheed, Izad-Yar Daniel

    2016-01-01

    and neuronal activity. Since capillaries are embedded in the O2-consuming neuropil, we have here examined whether activity-dependent dips in O2 tension drive capillary hyperemia. In vivo analyses showed that transient dips in tissue O2 tension elicit capillary hyperemia. Ex vivo experiments revealed that red...... blood cells (RBCs) themselves act as O2 sensors that autonomously regulate their own deformability and thereby flow velocity through capillaries in response to physiological decreases in O2 tension. This observation has broad implications for understanding how local changes in blood flow are coupled...

  10. Study on the relationship of cytochrome C expression and cerebral edema in perihematomal brain tissue in patients with hypertensive cerebral hemorrhage

    Institute of Scientific and Technical Information of China (English)

    CAI Heng; LIU Guixiang; XU Chunsheng; LIU Qingxin; XU Xiaobo

    2007-01-01

    Objective To investigate the expression of cytochrome C in perihematomal brain tissue and its relationship with the histopathological change and formation of cerebral edema in patients with hypertensive cerebral hemorrhage. Methods Thirty four patients (23 male, 11 female) of hypertensive cerebral hemorrhage in hospital from Sep. 2001 to Sep. 2002 were selected with a mean age 55.6± 10.2 years (from 35 to 75 years). The mean volume of hemorrhagic blood was 50.4±11.6 ml (from 25 to 85 ml). The perihematomal brain tissue was obtained from the minimally invasive surgery. Histopathological change and expressions of cytochrome C in perihematomal brain tissue was detected by histopathological and immunohistochemical techniques. The volume of perihematomal cerebral edema was determined by computed tomographic scan before operation. The results of staining and the volume of perihematomal cerebral edema were analyzed with double blind fashion. Results Perihematomal cerebral edema were found 12-72h after cerebral hemorrhage. Myelin sheath degeneration, condensation of nucleus and typical apopototic body were observed in perihematomal brain tissue. Expression of cytochrome C in perihematomal brain tissue was observed at 4 h and reached peak around 48-72 h after cerebral hemorrhage. Cytochrome C expressed higher positively in 16 patients and lower positively in 13 patients. Cytochrome C expression was not detected only in 5 patints. There were significant differences in volume of perihematomal cerebral edema with different expression of cytochrome C in perihematomal brain tissue (P<0.01). Conclusions Cytochrome C expression was upregulated in perihematomal brain tissue in patients with hypertensive cerebral hemorrhage. Cytochrome C might involve in the histopathological change and the formation of perihematomal cerebral edema.

  11. Positron emission tomography in cerebrovascular disease: The relationship between regional cerebral blood flow, blood volume and oxygen metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Herold, S.

    1985-03-01

    Positron emission tomography in cerebrovascular disease has demonstrated the importance of the relationship between regional cerebral blood flow and the cerebral metabolic activity. In acute stroke it has been found that within the first hours after the onset of symptoms cerebral blood flow in the affected area is more depressed than cerebral oxygen utilisation. This relative preservation of oxygen utilisation results from an increase in the oxygen extraction ratio far above its normal value. However, the oxygen extraction fraction subsequently falls in the following days indicating the transition from a situation of possibly reversible ischaemia to irreversible infarction. In patients with carotid occlusive disease an increase in the oxygen extraction ratio has been observed only in very few cases. It has been shown, however, that at an earlier stage the relationship between CBF and CBV (as CBF/CBV-ratio) provides a sensitive measure of diminished perfusion pressure which could be helpful for the selection of patients for EC-IC bypass surgery. In patients with sickle cell anaemia it has been found that oxygen delivery to the brain is maintained by an increase in cerebral blood flow, whereas the oxygen extraction ratio is not increased despite the presence of a low oxygen affinity haemoglobin. Preliminary observations in classical migraine suggest an ischaemic situation during the attack.

  12. Long-term existence of cerebral hypoxic tissue in a rat model of cerebral ischemia/reperfusion injury

    Institute of Scientific and Technical Information of China (English)

    Yidong Wang; Jingrui Pan; Yu Qiu; Xiangpen Li; Mei Li; Ying Peng

    2009-01-01

    BACKGROUND: Hypoxic tissue surrounding the ischemic core may represent the ischemic penumbra following cerebral infarction. However, some studies have shown that the duration of ischemic tissue is longer than previously believed.OBJECTIVE: To clarify whether cerebral hypoxic tissue could survive long-term and whether it is altered in rats following cerebral infarction; to establish an ischemia/reperfusion model in which hypoxic tissue exists for extended periods of time.DESIGN, TIME AND SETTING: A completely randomized grouping and controlled experiment was performed at the Experimental Animal Center of Sun Yat-sen University and Medical Research Center, the Second Affiliated Hospital of Sun Yat-sen University between June and December 2008. MATERIALS: 4,9-diaza-3,3,10,10-tetramethyldodecan-2, 11-dione dioxime (BnAO) (HL91), used as the hypoxic marker for autoradiography, was supplied by the Beijing Syncor Star Medicinal, China, and the flesh eluent Na99TcmO4 to mark HL91 was supplied by Guangzhou Medical Isotope Center of the China Institute of Atomic Energy. 2-(2-nitro-1H-imidazole-1-yl)-N-(2,2,3,3,3-pentafluoropropyl) acetamide (EF5) and its antibody ELK3-51, used as a hypoxic marker for immunofluorescence, were supplied by the University of Pennsylvania, USA.METHODS: Male Sprague Dawley rats were randomly divided into four groups: 1.5-hour ischemia/reperfusion group (1.5 h IR), 2-hour ischemia/reperfusion group (2 h IR), 3-hour ischemia/reperfusion group (3 h IR), and permanent ischemia (PI) group, with 21 rats in each group. The middle cerebral artery occlusion model was established using the intraluminal suture method, while reperfusion was performed by removing the suture at each observation time point. However, in the PI group, the suture was left in the artery.MAIN OUTCOME MEASURES: Area and average absorbance of fluorescence, representing hypoxic tissue, were measured by image-analysis.RESULTS: Autoradiography revealed positive hypoxia at days 1 and 14

  13. The Effect of Patient-Specific Cerebral Oxygenation Monitoring on Postoperative Cognitive Function: A Multicenter Randomized Controlled Trial

    Science.gov (United States)

    Ellis, Lucy; Murphy, Gavin J; Culliford, Lucy; Dreyer, Lucy; Clayton, Gemma; Downes, Richard; Nicholson, Eamonn; Stoica, Serban; Reeves, Barnaby C

    2015-01-01

    Background Indices of global tissue oxygen delivery and utilization such as mixed venous oxygen saturation, serum lactate concentration, and arterial hematocrit are commonly used to determine the adequacy of tissue oxygenation during cardiopulmonary bypass (CPB). However, these global measures may not accurately reflect regional tissue oxygenation and ischemic organ injury remains a common and serious complication of CPB. Near-infrared spectroscopy (NIRS) is a noninvasive technology that measures regional tissue oxygenation. NIRS may be used alongside global measures to optimize regional perfusion and reduce organ injury. It may also be used as an indicator of the need for red blood cell transfusion in the presence of anemia and tissue hypoxia. However, the clinical benefits of using NIRS remain unclear and there is a lack of high-quality evidence demonstrating its efficacy and cost effectiveness. Objective The aim of the patient-specific cerebral oxygenation monitoring as part of an algorithm to reduce transfusion during heart valve surgery (PASPORT) trial is to determine whether the addition of NIRS to CPB management algorithms can prevent cognitive decline, postoperative organ injury, unnecessary transfusion, and reduce health care costs. Methods Adults aged 16 years or older undergoing valve or combined coronary artery bypass graft and valve surgery at one of three UK cardiac centers (Bristol, Hull, or Leicester) are randomly allocated in a 1:1 ratio to either a standard algorithm for optimizing tissue oxygenation during CPB that includes a fixed transfusion threshold, or a patient-specific algorithm that incorporates cerebral NIRS monitoring and a restrictive red blood cell transfusion threshold. Allocation concealment, Internet-based randomization stratified by operation type and recruiting center, and blinding of patients, ICU and ward care staff, and outcome assessors reduce the risk of bias. The primary outcomes are cognitive function 3 months after

  14. Cerebral Oxygenation and Oxygen Extraction in the Preterm Infant during Desaturation : Effects of Increasing FiO(2) to Assist Recovery

    NARCIS (Netherlands)

    Baerts, Willem; Lemmers, Petra M. A.; van Bel, Frank

    2011-01-01

    Background: In the clinical setting, episodes of desaturation in newborn infants are often treated by increasing the fraction of inspired oxygen (FiO(2)). Objectives: To study the effect of an increase in FiO(2) on cerebral oxygenation during recovery from desaturation, as measured by near-infrared

  15. Challenges in understanding the impact of blood pressure management on cerebral oxygenation in the preterm brain

    Directory of Open Access Journals (Sweden)

    Aminath eAzhan

    2012-12-01

    Full Text Available Systemic hypotension in preterm infants has been related to increased mortality, cerebrovascular lesions and neurodevelopmental morbidity. Treatment of hypotension with inotropic medications aims at preservation of end organ perfusion and oxygen delivery, especially the brain. The common inotropic medications in preterm infants include dopamine, dobutamine, adrenalin, with adjunctive use of corticosteroids in cases of refractory hypotension. Whether maintenance of mean arterial blood pressure (MAP by use of inotropic medication is neuroprotective or not remains unclear. This review explores the different inotropic agents and their effects on perfusion and oxygenation in the preterm brain, in clinical studies as well as in animal models. Dopamine and adrenalin, because of their -adrenergic vasoconstrictor actions, have raised concerns of reduction in cerebral blood flow (CBF. Several studies in hypotensive preterm infants have shown that dopamine elevates CBF together with increased MAP, in keeping with limited cerebro-autoregulation. Adrenaline is also effective in raising cerebral perfusion together with MAP in preterm infants. Experimental studies in immature animals show no cerebro-vasoconstrictive effects of dopamine or adrenaline, but demonstrate the consistent findings of increased cerebral perfusion and oxygenation with the use of dopamine, dobutamine and adrenaline, alongside with raised MAP. Both clinical and animal studies report the transitory effects of adrenaline in increasing plasma lactate, and blood glucose, which might render its use as a 2nd line therapy. To investigate the cerebral effects of inotropic agents in long-term outcome in hypotensive preterm infants, carefully designed prospective research possibly including preterm infants with permissive hypotension is required. Preterm animal models would be useful in investigating the relationship between the physiological effects of inotropes and histopathology outcomes in

  16. Neuroprotection of hyperbaric oxygen therapy in sub-acute traumatic brain injury:not by immediately improving cerebral oxygen saturation and oxygen partial pressure

    Institute of Scientific and Technical Information of China (English)

    Bao-chun Zhou; Li-jun Liu; Bing Liu

    2016-01-01

    Although hyperbaric oxygen (HBO) therapy can promote the recovery of neural function in patients who have suffered traumatic brain injury (TBI), the underlying mechanism is unclear. We hypothesized that hyperbaric oxygen treatment plays a neuroprotective role in TBI by increasing regional transcranial oxygen saturation (rSO2) and oxygen partial pressure (PaO2). To test this idea, we compared two groups:a control group with 20 healthy people and a treatment group with 40 TBI patients. The 40 patients were given 100% oxygen of HBO for 90 minutes. Changes in rSO2 were measured. The controls were also examined for rSO2 and PaO2, but received no treatment. rSO2 levels in the patients did not differ signiifcantly after treatment, but levels before and after treatment were signiifcantly lower than those in the control group. PaO2 levels were signiifcantly decreased after the 30-minute HBO treatment. Our ifndings suggest that there is a disorder of oxygen metabolism in patients with sub-acute TBI. HBO does not immediately affect cerebral oxygen metabolism, and the underlying mechanism still needs to be studied in depth.

  17. Monitorization of the effects of spinal anaesthesia on cerebral oxygen saturation in elder patients using near-infrared spectroscopy

    Directory of Open Access Journals (Sweden)

    Aysegul Kusku

    2014-07-01

    Full Text Available OBJECTIVE: Central blockage provided by spinal anaesthesia enables realization of many surgical procedures, whereas hemodynamic and respiratory changes influence systemic oxygen delivery leading to the potential development of series of problems such as cerebral ischemia, myocardial infarction and acute renal failure. This study was intended to detect potentially adverse effects of hemodynamic and respiratory changes on systemic oxygen delivery using cerebral oxymetric methods in patients who underwent spinal anaesthesia. METHODS: Twenty-five ASA I-II Group patients aged 65-80 years scheduled for unilateral inguinal hernia repair under spinal anaesthesia were included in the study. Following standard monitorization baseline cerebral oxygen levels were measured using cerebral oximetric methods. Standardized Mini Mental Test (SMMT was applied before and after the operation so as to determine the level of cognitive functioning of the cases. Using a standard technique and equal amounts of a local anaesthetic drug (15 mg bupivacaine 5% intratechal blockade was performed. Mean blood pressure (MBP, maximum heart rate (MHR, peripheral oxygen saturation (SpO2 and cerebral oxygen levels (rSO2 were preoperatively monitored for 60 min. Pre- and postoperative haemoglobin levels were measured. The variations in data obtained and their correlations with the cerebral oxygen levels were investigated. RESULTS: Significant changes in pre- and postoperative measurements of haemoglobin levels and SMMT scores and intraoperative SpO2 levels were not observed. However, significant variations were observed in intraoperative MBP, MHR and rSO2 levels. Besides, a correlation between variations in rSO2, MBP and MHR was determined. CONCLUSION: Evaluation of the data obtained in the study demonstrated that post-spinal decline in blood pressure and also heart rate decreases systemic oxygen delivery and adversely effects cerebral oxygen levels. However, this downward change did

  18. Diagnosis of Compartment Syndrome Based on Tissue Oxygenation

    Science.gov (United States)

    2015-06-01

    was added in our model. Dobutamine is an inotropic agent commonly used in patients with cardiogenic shock to increase heart rate, contractility, and...to soft tissue edema and skin turgor changes after trauma that alter the depth of the muscle to be evaluated and the ability of the probe to maintain...and cardiogenic shock. Infection. 1991;19:317–323. 18. Bylund-Fellenius AC, Walker PM, Elander A, et al. Energy metabolism in relation to oxygen partial

  19. Low Cerebral Oxygen Consumption and Blood Flow in Patients With Cirrhosis and an Acute Episode of Hepatic Encephalopathy

    DEFF Research Database (Denmark)

    Iversen, Peter; Bak, Lasse Kristoffer; Waagepetersen, Helle Sønderby

    2009-01-01

    BACKGROUND & AIMS: It is unclear whether patients with hepatic encephalopathy (HE) have disturbed brain oxygen metabolism and blood flow. METHODS: We measured cerebral oxygen metabolism rate (CMRO(2)) by using (15)O-oxygen positron emission tomography (PET), and cerebral blood flow (CBF) by using....../min in patients with HE, 0.47 +/- 0.02 in patients without HE, and 0.49 +/- 0.03 in healthy subjects. CMRO(2) and CBF were correlated, and both variables correlated negatively with arterial ammonia concentration. Analysis of regional values, using individual magnetic resonance co-registrations, showed...... that the reductions in CMRO(2) and CBF in patients with HE were essentially generalized throughout the brain. CONCLUSIONS: The observations imply that reduced cerebral oxygen consumption and blood flow in cirrhotic patients with an acute episode of overt HE are associated with HE and not cirrhosis as such...

  20. Cerebral blood flow and oxygen metabolism in dementia with Lewy bodies

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Yoshitomo; Takahashi, Satoshi; Yonezawa, Hisashi [Iwate Medical Univ., Morioka (Japan). School of Medicine

    2000-06-01

    Regional cerebral blood flow (rCBF), oxygen metabolism (rCMRO{sub 2}) and the oxygen extraction fraction (rOEF) were measured using the steady-state {sup 15}O technique and positron emission tomography (PET) in six patients with dementia with Lewy bodies (DLB), and compared with ten patients with Alzheimer disease (AD) and six normal controls. In the AD patients, rCBF and rCMRO{sub 2} were significantly decreased in the frontal, parietal, and temporal cortices compared with controls. In DLB patients, rCBF and rCMRO{sub 2} were decreased in the frontal, parietal, temporal, and occipital cortices compared with controls, and were decreased more diffusely than in AD patients. rCBF and rCMRO{sub 2} were significantly decreased in occipital cortex compared with AD patients. rOEF was significantly increased in the parieto-temporal cortex in AD patients compared with controls. In DLB patients, rOEF was significantly increased not only in the parieto-temporal cortex but also in the occipital and frontal cortices compared with controls, and was significantly increased in the occipital cortex compared with AD patients. The diffuse reduction of cerebral blood flow and oxygen metabolism including the occipital cortex may be related to visual hallucination and other visuospatial deficits frequently seen in DLB patients. The increase in rOEF may be mainly due to the reduction in the vascular bed associated with decreased activity in the vasodilatory cholinergic system. (author)

  1. Monitoring microvascular free flaps with tissue oxygen measurement and PET.

    Science.gov (United States)

    Schrey, Aleksi R; Kinnunen, Ilpo A J; Grénman, Reidar A; Minn, Heikki R I; Aitasalo, Kalle M J

    2008-07-01

    Tissue oxygen measurement and positron emission tomography (PET) were evaluated as methods for predicting ischemia in microvascular free flaps of the head and neck. Ten patients with head and neck squamous cell cancer underwent resection of the tumour followed by microvascular reconstruction with a free flap. Tissue oxygenation of the flap (P(ti)O(2)) was continuously monitored for three postoperative (POP) days and the blood flow of the flap was assessed using oxygen-15 labelled water and PET. In three free flaps a perfusion problem was suspected due to a remarkable drop in P(ti)O(2)-values, due to two anastomosis problems and due to POP turgor. No flap losses occurred. During the blood flow measurements with PET [mean 8.5 mL 100 g(-1) min(-1 )(SD 2.5)], the mean P(ti)O(2) of the flaps [46.8 mmHg (SD 17.0)] appeared to correlate with each other in each patient (pmonitoring system of free flaps. The perfusion-study with PET correlates with P(ti)O(2)-measurement.

  2. Effects of aging on cerebral blood flow, oxygen metabolism, and blood oxygenation level dependent responses to visual stimulation.

    Science.gov (United States)

    Ances, Beau M; Liang, Christine L; Leontiev, Oleg; Perthen, Joanna E; Fleisher, Adam S; Lansing, Amy E; Buxton, Richard B

    2009-04-01

    Calibrated functional magnetic resonance imaging (fMRI) provides a noninvasive technique to assess functional metabolic changes associated with normal aging. We simultaneously measured both the magnitude of the blood oxygenation level dependent (BOLD) and cerebral blood flow (CBF) responses in the visual cortex for separate conditions of mild hypercapnia (5% CO(2)) and a simple checkerboard stimulus in healthy younger (n = 10, mean: 28-years-old) and older (n = 10, mean: 53-years-old) adults. From these data we derived baseline CBF, the BOLD scaling parameter M, the fractional change in the cerebral metabolic rate of oxygen consumption (CMRO(2)) with activation, and the coupling ratio n of the fractional changes in CBF and CMRO(2). For the functional activation paradigm, the magnitude of the BOLD response was significantly lower for the older group (0.57 +/- 0.07%) compared to the younger group (0.95 +/- 0.14%), despite the finding that the fractional CBF and CMRO(2) changes were similar for both groups. The weaker BOLD response for the older group was due to a reduction in the parameter M, which was significantly lower for older (4.6 +/- 0.4%) than younger subjects (6.5 +/- 0.8%), most likely reflecting a reduction in baseline CBF for older (41.7 +/- 4.8 mL/100 mL/min) compared to younger (59.6 +/- 9.1 mL/100 mL/min) subjects. In addition to these primary responses, for both groups the BOLD response exhibited a post-stimulus undershoot with no significant difference in this magnitude. However, the post-undershoot period of the CBF response was significantly greater for older compared to younger subjects. We conclude that when comparing two populations, the BOLD response can provide misleading reflections of underlying physiological changes. A calibrated approach provides a more quantitative reflection of underlying metabolic changes than the BOLD response alone.

  3. Effects of incremental exercise on cerebral oxygenation measured by near-infrared spectroscopy: a systematic review.

    Science.gov (United States)

    Rooks, Cherie R; Thom, Nathaniel J; McCully, Kevin K; Dishman, Rod K

    2010-10-01

    We conducted a systematic review and meta-regression analysis to quantify effects of exercise on brain hemodynamics measured by near-infrared spectroscopy (NIRS). The results indicate that acute incremental exercise (categorized relative to aerobic capacity (VO(2)peak) as low - <30% VO(2)peak; moderate - ≥30% VO(2)peak to <60% VO(2)peak; hard - ≥60% VO(2)peak to oxygenated hemoglobin (O(2)Hb) or other measures of oxygen level (O(2)Hbdiff) or saturation (SCO(2)) (0.92±0.67, 1.17), deoxygenated hemoglobin (dHb) (0.87±0.56, 1.19), and blood volume estimated by total hemoglobin (tHb) (1.21±0.84, 1.59). After peaking at hard intensities, cerebral oxygen levels dropped during very hard intensities. People who were aerobically trained attained higher levels of cortical oxygen, dHb, and tHb than untrained people during very hard intensities. Among untrained people, a marked drop in oxygen levels and a small increase in dHb at very hard intensities accompanied declines in tHb, implying reduced blood flow. In 6 studies of 222 patients with heart or lung conditions, oxygenation and dHb were lowered or unchanged during exercise compared to baseline. In conclusion, prefrontal oxygenation measured with NIRS in healthy people showed a quadratic response to incremental exercise, rising between moderate and hard intensities, then falling at very hard intensities. Training status influenced the responses. While methodological improvements in measures of brain oxygen are forthcoming, these results extend the evidence relevant to existing models of central limitations to maximal exercise.

  4. Functional and anatomical evidence of cerebral tissue hypoxia in young sickle cell anemia mice.

    Science.gov (United States)

    Cahill, Lindsay S; Gazdzinski, Lisa M; Tsui, Albert Ky; Zhou, Yu-Qing; Portnoy, Sharon; Liu, Elaine; Mazer, C David; Hare, Gregory Mt; Kassner, Andrea; Sled, John G

    2017-03-01

    Cerebral ischemia is a significant source of morbidity in children with sickle cell anemia; however, the mechanism of injury is poorly understood. Increased cerebral blood flow and low hemoglobin levels in children with sickle cell anemia are associated with increased stroke risk, suggesting that anemia-induced tissue hypoxia may be an important factor contributing to subsequent morbidity. To better understand the pathophysiology of brain injury, brain physiology and morphology were characterized in a transgenic mouse model, the Townes sickle cell model. Relative to age-matched controls, sickle cell anemia mice demonstrated: (1) decreased brain tissue pO2 and increased expression of hypoxia signaling protein in the perivascular regions of the cerebral cortex; (2) elevated basal cerebral blood flow , consistent with adaptation to anemia-induced tissue hypoxia; (3) significant reduction in cerebrovascular blood flow reactivity to a hypercapnic challenge; (4) increased diameter of the carotid artery; and (5) significant volume changes in white and gray matter regions in the brain, as assessed by ex vivo magnetic resonance imaging. Collectively, these findings support the hypothesis that brain tissue hypoxia contributes to adaptive physiological and anatomic changes in Townes sickle cell mice. These findings may help define the pathophysiology for stroke in children with sickle cell anemia.

  5. Effects of diving and oxygen on autonomic nervous system and cerebral blood flow.

    Science.gov (United States)

    Winklewski, Pawel J; Kot, Jacek; Frydrychowski, Andrzej F; Nuckowska, Magdalena K; Tkachenko, Yurii

    2013-09-01

    Recreational scuba diving is a popular leisure activity with the number of divers reaching several millions worldwide. Scuba diving represents a huge challenge for integrative physiology. In mammalian evolution, physiological reflexes developed to deal with lack of oxygen, rather than with an excess, which makes adaptations to scuba diving more difficult to describe and understand than those associated with breath-hold diving. The underwater environment significantly limits the use of equipment to register the organism's functions, so, in most instances, scientific theories are built on experiments that model real diving to some extent, like hyperbaric exposures, dive reflexes or water immersion. The aim of this review is to summarise the current knowledge related to the influence exerted by physiological conditions specific to diving on the autonomic nervous system and cerebral blood flow. The main factors regulating cerebral blood flow during scuba diving are discussed as follows: 1) increased oxygen partial pressure; 2) immersion-related trigemino-cardiac reflexes and 3) exposure to cold, exercise and stress. Also discussed are the potential mechanisms associated with immersion pulmonary oedema.

  6. Cerebral oxygenation monitoring in patients with bilateral carotid stenosis undergoing urgent cardiac surgery: Observational case series

    Directory of Open Access Journals (Sweden)

    Dincer Aktuerk

    2016-01-01

    Full Text Available Background: Patients with significant bilateral carotid artery stenosis requiring urgent cardiac surgery have an increased risk of stroke and death. The optimal management strategy remains inconclusive, and the available evidence does not support the superiority of one strategy over another. Materials and Methods: A number of noninvasive strategies have been developed for minimizing perioperative stroke including continuous real-time monitoring of cerebral oxygenation with near-infrared spectroscopy (NIRS. The number of patients presenting with this combination (bilateral significant carotid stenosis requiring urgent cardiac surgery in any single institution will be small and hence there is a lack of large randomized studies. Results: This case series describes our early experience with NIRS in a select group of patients with significant bilateral carotid stenosis undergoing urgent cardiac surgery (n = 8. In contrast to other studies, this series is a single surgeon, single center study, where the entire surgery (both distal ends and proximal ends was performed during single aortic clamp technique, which effectively removes several confounding variables. NIRS monitoring led to the early recognition of decreased cerebral oxygenation, and corrective steps (increased cardiopulmonary bypass flow, increased pCO 2 , etc., were taken. Conclusion: The study shows good clinical outcome with the use of NIRS. This is our "work in progress," and we aim to conduct a larger study.

  7. Temporal and topographic profiles of tissue hypoxia following transient focal cerebral ischemia in rats.

    Science.gov (United States)

    Noto, Takahisa; Furuichi, Yasuhisa; Ishiye, Masayuki; Matsuoka, Nobuya; Aramori, Ichiro; Mutoh, Seitaro; Yanagihara, Takehiko; Manabe, Noboru

    2006-08-01

    Intravascular accumulation of blood cells after brain ischemia-reperfusion can cause obstruction of cerebral blood flow and tissue hypoxia/ischemia as a consequence. In the present study, we examined temporal and topographic changes of tissue hypoxia/ischemia after occlusion of the middle cerebral artery (MCA) for 60 min in rats with immunohistochemical staining for hypoxia (2-nitroimidazole hypoxia marker: hypoxyprobe-1 adducts). Our results showed that tissue hypoxia expressed as positive staining for hypoxyprobe-1 adducts preceded neuronal degeneration. Platelets and granulocytes were detected close to the hypoxyprobe-1 adducts positive area. These results suggested that the hypoxic environment could persist even after reperfusion of MCA, because of vascular obstruction with accumulation of platelets and granulocytes.

  8. Unruptured Cerebral Aneurysm Detected after Intravenous Tissue Plasminogen Activator for Stroke

    Directory of Open Access Journals (Sweden)

    Yukihiro Yoneda

    2009-06-01

    Full Text Available Therapeutic guidelines of intravenous thrombolysis with tissue plasminogen activator (tPA for hyperacute ischemic stroke are very strict. Because of potential higher risk of bleeding complications, the presence of unruptured cerebral aneurysm is a contraindication for systemic thrombolysis with tPA. According to the standard CT criteria, a 66-year-old woman who suddenly developed aphasia and hemiparesis received intravenous tPA within 3 h after ischemic stroke. Magnetic resonance angiography during tPA infusion was performed and the presence of a small unruptured cerebral aneurysm was suspected at the anterior communicating artery. Delayed cerebral angiography confirmed an aneurysm with a size of 7 mm. The patient did not experience any adverse complications associated with the aneurysm. Clinical experiences of this kind of accidental off-label thrombolysis may contribute to modify the current rigid tPA guidelines for stroke.

  9. Database of normal human cerebral blood flow, cerebral blood volume, cerebral oxygen extraction fraction and cerebral metabolic rate of oxygen measured by positron emission tomography with {sup 15}O-labelled carbon dioxide or water, carbon monoxide and oxygen: a multicentre study in Japan

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Hiroshi [Department of Radiology and Nuclear Medicine, Akita Research Institute of Brain and Blood Vessels, Akita (Japan); Department of Nuclear Medicine and Radiology, Division of Brain Sciences, Institute of Development, Aging and Cancer, Tohoku University, 4-1 Seiryo-Machi, 980-8575, Aoba-Ku, Sendai (Japan); Kanno, Iwao [Department of Radiology and Nuclear Medicine, Akita Research Institute of Brain and Blood Vessels, Akita (Japan); Kato, Chietsugu [Department of Nuclear Medicine, Hokkaido University School of Medicine, Sapporo (Japan); Sasaki, Toshiaki [Cyclotoron Research Center, Iwate Medical University, Morioka (Japan); Ishii, Kenji [Positron Medical Center, Tokyo Metropolitan Institute of Gerontology, Tokyo (Japan); Ouchi, Yasuomi [Positron Medical Center, Hamamatsu Medical Center, Hamakita (Japan); Iida, Akihiko [Nagoya City Rehabilitation Center, Nagoya (Japan); Okazawa, Hidehiko [PET Unit, Research Institute, Shiga Medical Center, Moriyama (Japan); Hayashida, Kohei [Department of Radiology, National Cardiovascular Center, Suita, Osaka (Japan); Tsuyuguchi, Naohiro [Department of Neurosurgery, Osaka City University Medical School, Osaka (Japan); Ishii, Kazunari [Division of Imaging Research, Hyogo Institute for Aging Brain and Cognitive Disorders, Himeji, Hyogo (Japan); Kuwabara, Yasuo [Department of Radiology, Faculty of Medicine, Kyushu University, Fukuoka (Japan); Senda, Michio [Department of Image-based Medicine, Institute of Biomedical Research and Innovation, Kobe (Japan)

    2004-05-01

    Measurement of cerebral blood flow (CBF), cerebral blood volume (CBV), cerebral oxygen extraction fraction (OEF) and cerebral metabolic rate of oxygen (CMRO{sub 2}) by positron emission tomography (PET) with oxygen-15 labelled carbon dioxide (C{sup 15}O{sub 2}) or {sup 15}O-labelled water (H{sub 2}{sup 15}O), {sup 15}O-labelled carbon monoxide (C{sup 15}O) and {sup 15}O-labelled oxygen ({sup 15}O{sub 2}) is useful for diagnosis and treatment planning in cases of cerebrovascular disease. The measured values theoretically depend on various factors, which may differ between PET centres. This study explored the applicability of a database of {sup 15}O-PET by examining between-centre and within-centre variation in values. Eleven PET centres participated in this multicentre study; seven used the steady-state inhalation method, one used build-up inhalation and three used bolus administration of C{sup 15}O{sub 2} (or H{sub 2}{sup 15}O) and {sup 15}O{sub 2}. All used C{sup 15}O for measurement of CBV. Subjects comprised 70 healthy volunteers (43 men and 27 women; mean age 51.8{+-}15.1 years). Overall mean{+-}SD values for cerebral cortical regions were: CBF=44.4{+-}6.5 ml 100 ml{sup -1} min{sup -1}; CBV=3.8{+-}0.7 ml 100 ml{sup -1}; OEF=0.44{+-}0.06; CMRO{sub 2}=3.3{+-}0.5 ml 100 ml{sup -1} min{sup -1}. Significant between-centre variation was observed in CBV, OEF and CMRO{sub 2} by one-way analysis of variance. However, the overall inter-individual variation in CBF, CBV, OEF and CMRO{sub 2} was acceptably small. Building a database of normal cerebral haemodynamics obtained by the{sup 15}O-PET methods may be practicable. (orig.)

  10. Cerebral energy metabolism during induced mitochondrial dysfunction

    DEFF Research Database (Denmark)

    Nielsen, T H; Bindslev, TT; Pedersen, S M

    2013-01-01

    In patients with traumatic brain injury as well as stroke, impaired cerebral oxidative energy metabolism may be an important factor contributing to the ultimate degree of tissue damage. We hypothesize that mitochondrial dysfunction can be diagnosed bedside by comparing the simultaneous changes in...... in brain tissue oxygen tension (PbtO(2)) and cerebral cytoplasmatic redox state. The study describes cerebral energy metabolism during mitochondrial dysfunction induced by sevoflurane in piglets....

  11. Imaging Evidence for Cerebral Hyperperfusion Syndrome after Intravenous Tissue Plasminogen Activator for Acute Ischemic Stroke

    Directory of Open Access Journals (Sweden)

    Yi Zhang

    2016-01-01

    Full Text Available Background. Cerebral hyperperfusion syndrome (CHS, a rare complication after cerebral revascularization, is a well-described phenomenon after carotid endarterectomy or carotid artery stenting. However, the imaging evidence of CHS after intravenous tissue plasminogen activator (iv tPA for acute ischemic stroke (AIS has not been reported. Case Report. Four patients were determined to have manifestations of CHS with clinical deterioration after treatment with iv tPA, including one patient who developed seizure, one patient who had a deviation of the eyes toward lesion with worsened mental status, and two patients who developed worsened hemiparesis. In all four patients, postthrombolysis head CT examinations were negative for hemorrhage; CT angiogram showed patent cervical and intracranial arterial vasculature; CT perfusion imaging revealed hyperperfusion with increased relative cerebral blood flow and relative cerebral blood volume and decreased mean transit time along with decreased time to peak in the clinically related artery territory. Vascular dilation was also noted in three of these four cases. Conclusions. CHS should be considered in patients with clinical deterioration after iv tPA and imaging negative for hemorrhage. Cerebral angiogram and perfusion studies can be useful in diagnosing CHS thereby helping with further management.

  12. Effects of pH management during deep hypothermic bypass on cerebral oxygenation:alpha-stat versus pH-stat

    Institute of Scientific and Technical Information of China (English)

    郦志军; 尹小妹; 叶箭

    2004-01-01

    Objective: There is a remarkable lack of scientific evidence to support the option to use alpha-stat or pH-stat management, as to which is more beneficial to brain protection during deep hypothermic CPB. This study examined cortical blood flow (CBF), cerebral oxygenation, and brain oxygen consumption in relation to deep hypothermic CPB with alpha-stat or pH-stat management. Methods: Twenty-two pigs were cooled with alpha-stat or pH-stat during CPB to 15℃ esophageal temperature. CBF and cerebral oxygenation were measured continuously with a laser flowmeter and near-infrared spectroscopy, respectively. Brain oxygen consumption was measured with standard laboratory techniques. Results: During CPB cooling, CBF was significantly decreased, about 52.2%±6.3% (P<0.01 vs 92.6%±6.5% of pH-stat) at 15℃ in alpha-stat,whereas there were no significant changes in CBF in pH-stat. While cooling down, brain oxygen extraction (OER) progressively decreased, about 9.5%±0.9% and 10.9%±1.5% at 15 ℃ in alpha-stat and pH-stat, respectively. At 31℃ the decreased value in pH-stat was lower than in alpha-stat (29.9%±2.7% vs 22.5%±1.9%; P<0.05). The ratio of CBF/OER were 2.0±0.3 in alpha-stat and pH-stat, respectively; it was kept in constant level in alpha-stat, and significantly increased by 19℃ to 15℃ in pH-stat (4.9±0.9 vs 2.3±0.4; P<0.01). In mild hypothermia, cerebral oxyhemoglobin and oxygen saturation in alpha-stat were greater than that in pH-stat (102.5%±1.4% vs 99.1%±0.7%; P<0.05). In deep hypothermia, brain oxygen saturation in pH-stat was greater than that in alpha-stat (99.2%±1.0% vs 93.8%±1.0%; P<0.01), and deoxyhemoglobin in pH-stat decreased more greatly than that in alpha-stat (28.7%±6.8% vs 54.1%±4.7%; P<0.05). Conclusions: In mild hypothermic CPB, brain tissue oxygen saturation was greater in alpha-stat than in pH-stat. However, cerebral oxygenation and brain tissue oxygen saturation were better in pH-stat than in alpha-stat during

  13. Investigation of tissue oxygenation by in vivo laser-induced photodissociation of cutaneous arterial blood oxyhemoglobin

    Science.gov (United States)

    Asimov, M. M.; Korolevich, A. N.

    2008-06-01

    A novel method of direct control of local tissue oxygenation based on laser-induced photodissociation of oxyhemoglobin in cutaneous blood vessels is discussed. New technology in selective and local increase of the concentration of free molecular oxygen in tissue that enhances metabolism of cells is demonstrated. Direct in vivo measurements of the tissue oxygen tension are carried out on human skin. Kinetics of oxygen tension in tissue is investigated under the effect of He-Ne laser radiation at the power of 1mW relatively to initial value of tissue oxygen tension. The results of experimental study the kinetics of oxygen distribution into tissue from arterial blood is presented. Biomedical applications of proposed new technology in laser therapy of pathologies where elimination of local tissue hypoxia is critical are discussed.

  14. Higher temporal resolution is necessary for continuous-wave near -infrared spectrophotometric monitors in both cerebral and muscular tissue oximetry

    Science.gov (United States)

    Chihara, Eiichi; Shiga, Toshikazu; Tanabe, Kazuhisa; Tanaka, Yoshifumi

    1998-01-01

    Conventional near infrared spectrophotometric monitors have temporal resolution of less than about 1 Hz. However, physiological Hb signals such as pulsation and muscle contraction have higher frequency than 1 Hz. Insufficient sampling rates inevitably lead aliasing of the recorded signals in tissue oximetry for both brain and muscle. Cerebral Hb signals (57 y.o. female artificially ventilated under general anesthesia) and thigh muscle (22 y.o. male with 20 W - 240 W exercise at 1 Hz cycling in semirecumbent ergometer) were measured with NIRS monitor with temporal resolution of 10 Hz (OMRON Co. Ltd., Japan). The detail of physiological fluctuations such as pulsation, ventilation, and muscle pumping was clearly recognized with a 10 Hz sampling. The comparison with recalculated waveforms at slower sampling rate (0.5 Hz, 1 Hz, 2 Hz) revealed that with slower sampling than 1 Hz cerebral respiratory waves were deformed by pulsation, and that magnitudes of muscle pumping could not be properly evaluated in dynamic exercise. In both pulsatile and muscle contractile cycle a phase delay between oxygenated component and deoxygenated one was also detected, which has been overlooked by conventional NIRS monitoring.

  15. Liposome-encapsulated hemoglobin reduces the size of cerebral infarction in rats: effect of oxygen affinity.

    Science.gov (United States)

    Fukumoto, Dai; Kawaguchi, Akira T; Haida, Munetaka; Yamano, Mariko; Ogata, Yoshitaka; Tsukada, Hideo

    2009-02-01

    Liposome-encapsulated hemoglobin (LEH) with a low oxygen affinity (l-LEH, P(50) = 45 mm Hg) was found to be protective in the rodent and primate models of ischemic stroke. This study investigated the role of LEH with a high O(2) affinity (h-LEH, P(50) = 10 mm Hg) in its protective effect on brain ischemia. The extent of cerebral infarction was determined 24 h after photochemically induced thrombosis of the middle cerebral artery from the integrated area of infarction detected by triphenyltetrazolium chloride staining in rats receiving various doses of h-LEH as well as l-LEH. Both h-LEH and l-LEH significantly reduced the extent of cortical infarction. h-LEH remained protective at a lower concentration (minimal effective dose [MED]: 0.08 mL/kg) than l-LEH (MED: 2 mL/kg) in the cortex. h-LEH reduced the infarction extent in basal ganglia as well (MED: 0.4 mL/kg), whereas l-LEH provided no significant protection. h-LEH provided better protection than l-LEH. The protective effect of both high- and low-affinity LEH may suggest the importance of its small particle size (230 nm) as compared to red blood cells. The superiority of h-LEH over l-LEH supports an optimal O(2) delivery to the ischemic penumbra as the mechanism of action in protecting against brain ischemia and reperfusion.

  16. Smoking normalizes cerebral blood flow and oxygen consumption after 12-hour abstention

    DEFF Research Database (Denmark)

    Seyedi Vafaee, Manouchehr; Gjedde, Albert; Imamirad, Nasrin

    2015-01-01

    measurements of cerebral blood flow (CBF) and metabolic rate of oxygen (CMRO2) in 12 smokers who had refrained from smoking overnight, and in a historical group of nonsmokers, testing the prediction that overnight abstinence results in widespread, coupled reductions of CBF and CMRO2. At the end......Acute nicotine administration stimulates [14C]deoxyglucose trapping in thalamus and other regions of rat brain, but acute effects of nicotine and smoking on energy metabolism have rarely been investigated in human brain by positron emission tomography (PET). We obtained quantitative PET...... of the abstention period, global grey-matter CBF and CMRO2 were both reduced by 17% relative to nonsmokers. At 15 minutes after renewed smoking, global CBF had increased insignificantly, while global CMRO2 had increased by 11%. Regional analysis showed that CMRO2 had increased in the left putamen and thalamus...

  17. Optical measurement of cerebral hemodynamics and oxygen metabolism in neonates with congenital heart defects

    Science.gov (United States)

    Durduran, Turgut; Zhou, Chao; Buckley, Erin M.; Kim, Meeri N.; Yu, Guoqiang; Choe, Regine; Gaynor, J. William; Spray, Thomas L.; Durning, Suzanne M.; Mason, Stefanie E.; Montenegro, Lisa M.; Nicolson, Susan C.; Zimmerman, Robert A.; Putt, Mary E.; Wang, Jiongjiong; Greenberg, Joel H.; Detre, John A.; Yodh, Arjun G.; Licht, Daniel J.

    2010-05-01

    We employ a hybrid diffuse correlation spectroscopy (DCS) and near-infrared spectroscopy (NIRS) monitor for neonates with congenital heart disease (n=33). The NIRS-DCS device measured changes during hypercapnia of oxyhemoglobin, deoxyhemoglobin, and total hemoglobin concentrations; cerebral blood flow (rCBFDCS); and oxygen metabolism (rCMRO2). Concurrent measurements with arterial spin-labeled magnetic resonance imaging (rCBFASL-MRI, n=12) cross-validate rCBFDCS against rCBFASL-MRI, showing good agreement (R=0.7, p=0.01). The study demonstrates use of NIRS-DCS on a critically ill neonatal population, and the results indicate that the optical technology is a promising clinical method for monitoring this population.

  18. Cerebral misery perfusion diagnosed using hypercapnic blood-oxygenation-level-dependent contrast functional magnetic resonance imaging: a case report

    Directory of Open Access Journals (Sweden)

    D'Souza Olympio

    2010-02-01

    Full Text Available Abstract Introduction Cerebral misery perfusion represents a failure of cerebral autoregulation. It is an important differential diagnosis in post-stroke patients presenting with collapses in the presence of haemodynamically significant cerebrovascular stenosis. This is particularly the case when cortical or internal watershed infarcts are present. When this condition occurs, further investigation should be done immediately. Case presentation A 50-year-old Caucasian man presented with a stroke secondary to complete occlusion of his left internal carotid artery. He went on to suffer recurrent seizures. Neuroimaging demonstrated numerous new watershed-territory cerebral infarcts. No source of arterial thromboembolism was demonstrable. Hypercapnic blood-oxygenation-level-dependent-contrast functional magnetic resonance imaging was used to measure his cerebrovascular reserve capacity. The findings were suggestive of cerebral misery perfusion. Conclusions Blood-oxygenation-level-dependent-contrast functional magnetic resonance imaging allows the inference of cerebral misery perfusion. This procedure is cheaper and more readily available than positron emission tomography imaging, which is the current gold standard diagnostic test. The most evaluated treatment for cerebral misery perfusion is extracranial-intracranial bypass. Although previous trials of this have been unfavourable, the results of new studies involving extracranial-intracranial bypass in high-risk patients identified during cerebral perfusion imaging are awaited. Cerebral misery perfusion is an important and under-recognized condition in which emerging imaging and treatment modalities present the possibility of practical and evidence-based management in the near future. Physicians should thus be aware of this disorder and of recent developments in diagnostic tests that allow its detection.

  19. ADRB2 gly16gly Genotype, Cardiac Output, and Cerebral Oxygenation in Patients Undergoing Anesthesia for Abdominal Aortic Aneurysm Surgery

    DEFF Research Database (Denmark)

    Staalso, Jonatan Myrup; Rokamp, Kim Zillo; Olesen, Niels D.

    2016-01-01

    BACKGROUND: Gly16arg polymorphism of the adrenergic [beta]2-receptor is associated with the elevated cardiac output (Q) in healthy gly16-homozygotic subjects. We questioned whether this polymorphism also affects Q and regional cerebral oxygen saturation (SCO2) during anesthesia in vascular surgic...

  20. Hyperbaric oxygen therapy for cerebral blood flow and electroencephalogram in patients with acute cerebral infarction Choice for therapeutic occasion

    Institute of Scientific and Technical Information of China (English)

    Lei Chen; Fei Li; Dexiang Gu

    2007-01-01

    BACKGROUND: Hyperbaric oxygen (HBO) therapy increases blood oxygen content, changes cerebral blood flow (CBF) and cerebral metabolism. Its therapeutic effects on cerebrovascular disease have been fully confirmed, but the occasion for HBO therapy is still unclear.OBJECTIVE: To observe the therapeutic effects of HBO therapy at different time on CBF and electroencephalogram (EEG) in patients with acute cerebral infarction (CI).DESIGN: Randomized controlled trial.SETTING: Department of Neurology, Shidong Hospital, Yangpu District of Shanghai.PARTICIPANTS: Ninety-six inpatients with acute CI, admitted to Department of Neurology, Shidong Hospital, Yangpu District of Shanghai from January 2001 to December 2006, were involved in this experiment. The involved participants met the diagnosis criteria of acute CI and confirmed by skull CT or MRI. They all were patients with moderate CI (16- 30 points) according to neurologic deficit score formulated by Chinese Medical Association. Informed consents of detected items and therapeutic regimen were obtained from all the involved participants. They were randomized into two groups with 48 in each:early-stage treatment group and advanced-stage treatment group. Among the 48 patients in the early-stage treatment group, 21 male and 27 female, aged 53 -68 years, 22 patients were found with basal ganglia infarction, 10 with brain lobe infarction, 16 with multiple infarction, 27 accompanied with hypertension and 2 accompanied with diabetes mellitus. Among the 48 patients in the advanced-stage treatment group, 23 male and 25 female, aged 52 - 71 years, 25 patients were found with basal ganglia infarction, 10 with brain lobe infarction, 12 with multiple infarction, 1 with brain stem infarction, 28 accompanied with hypertension and 1 accompanied with diabetes mellitus.METHODS: After admission, patients of two groups received routine drug treatment. ① Patients in the early-stage treatment group and advanced-stage treatment group began to

  1. Cerebral oxygenation and processed EEG response to clamping and shunting during carotid endarterectomy under general anesthesia.

    Science.gov (United States)

    Perez, William; Dukatz, Christopher; El-Dalati, Sami; Duncan, James; Abdel-Rasoul, Mahmoud; Springer, Andrew; Go, Michael R; Dzwonczyk, Roger

    2015-12-01

    Clamping and shunting during carotid endarterectomy (CEA) surgery causes changes in cerebral blood flow. The purpose of this study was to assess and compare, side by side, the cerebral oxygenation (rSO2) and processed electroencephalogram (EEG) response bilaterally to carotid artery clamping and shunting in patients undergoing CEA under general anesthesia. With institutional approval and written informed consent, patients undergoing CEA under general anesthesia and routine carotid artery shunting were recorded bilaterally, simultaneously and continuously with an rSO2 and processed EEG monitor. The response of the monitors during carotid artery clamping and shunting were assessed and compared between monitors and bilaterally within each monitor. Sixty-nine patients were included in the study. At clamping the surgical-side and contralateral-side rSO2 dropped significantly below the baseline incision value (-17.6 and -9.4% respectively). After shunting, the contralateral-side rSO2 returned to baseline while the surgical-side rSO2 remained significantly below baseline (-9.0%) until the shunt was removed following surgery. At clamping the surgical-side and contralateral-side processed EEG also dropped below baseline (-19.9 and -20.6% respectively). However, following shunt activation, the processed EEG returned bilaterally to baseline. During the course of this research, we found the rSO2 monitor to be clinically more robust (4.4% failure rate) than the processed EEG monitor (20.0% failure rate). There was no correlation between the rSO2 or processed EEG changes that occurred immediately after clamping and the degree of surgical side stenosis measured pre-operatively. Both rSO2 and processed EEG respond to clamping and shunting during CEA. Cerebral oximetry discriminates between the surgical and contralateral side during surgery. The rSO2 monitor is more reliable in the real-world clinical setting. Future studies should focus on developing algorithms based on these

  2. Tissue characterization in cerebral ischemia using multiparameter MRI

    Science.gov (United States)

    Soltanian-Zadeh, Hamid; Hammoud, Rabih; Jacobs, Michael A.; Patel, Suresh C.; Mitsias, Panayiotis D.; Pasnoor, Mamatha; Knight, Robert; Zheng, Zhang G.; Lu, Mei; Chopp, Michael

    2001-05-01

    After pre-processing and segmentation, the proposed method scores tissue regions between 1 and N. Score 1 is assigned to normal white matter and score N to CSF. Lesion zones are assigned a score based on their relative levels of similarities to white matter and CSF. To evaluate the method, 15 rats were imaged by a 7T MRI system at one of the three time points (acute, sub-acute, chronic) after MCA occlusion. Then, they were sacrificed and their brains were sliced and prepared for histological studies. MRI of 2 or 3 slices of each rat brain, using 2 DWI (b equals 400, b equals 800), 1 PDWI, 1 T2WI, and 1 T1WI, was used and an MRI score between 1 and 100 (N equals 100) was found for each region. Segmented regions were mapped onto the histology images and were scored by an experienced pathologist, from 1 to 10. MRI scores were validated using histology scores. To this end, correlation coefficients between the two scores (MRI and histology) were found. The results showed excellent correlations between MRI and histology scores at different time points.

  3. Depressed cerebral oxygen metabolism in patients with chronic renal failure. A positron emission tomography study

    Energy Technology Data Exchange (ETDEWEB)

    Hirakata, Hideki; Kanai, Hidetoshi; Nakane, Hiroshi; Fujii, Ken-ichiro; Hirakata, Eriko; Ibayashi, Setsuro; Kuwabara, Yasuo; Deenitchna, S.S.; Fujishima, Masatoshi [Kyushu Univ., Fukuoka (Japan). Graduate School of Medical Sciences

    2001-07-01

    In order to elucidate brain oxygen metabolism in uremic patients, the regional cerebral blood flow (rCBF), oxygen extraction (rOEF) and oxygen metabolism (rCMRO{sub 2}) were measured by positron emission tomography (PET) in both 10 hemodialysis patients (HD: male [m]/female [f]=2/8, age of 49{+-}3 [SEM] years old, HD duration of 113{+-}26 months) and 13 pre-dialysis renal failure patients (CRF: m/f=10/3, age of 61{+-}2 years old, serum creatinine (SCr) of 6.3{+-}1.0 mg/dl). Data were compared with 20 non-uremic subjects (Control: m/f=7/13, age of 62{+-}2 years old, SCr of 0.9{+-}0.1 mg/dl). They had no neurological abnormalities, congestive heart failure, history of cerebrovascular accident, diabetes mellitus, or symptomatic brain lesion on magnetic resonance imaging. The age of HD was significantly younger than the other groups (p<0.02) and the hemoglobin (Hb) levels in both HD (10.5{+-}0.5 g/dl) and CRF (9.8{+-}0.9) were significantly lower than that in Control (13.3{+-}0.3) (p<0.02). In the hemisphere, rCMRO{sub 2} in both HD (1.82{+-}0.10 ml/min/100 g) and CRF (1.95{+-}0.09) showed significantly lower values as compared to Control (2.23{+-}0.05) (p<0.01, respectively). Hemispheric rCBF in HD (35.6{+-}2.1 ml/100 g/min) and in CRF (36.1{+-}2.1) were not different from that in Control (31.8{+-}1.4). Hemispheric rOEF in CRF (45.7{+-}1.6%) was significantly higher than that in Control (40.5{+-}1.2%) (p<0.02), but that in HD (43.7{+-}1.9%) did not increase significantly. These tendencies were similar in all regions of interest, especially in the cerebral cortices, but not in the cerebellum. All PET parameters in the frontal cortices tended to show the lowest value in renal failure patients. For all HD patients, rCBF in both the frontal cortex and the white matter correlated inversely with HD duration (frontal cortex: r=-0.649, p<0.05; white matter: r=-0.706, p<0.02). Based on these data, it is concluded that brain oxygen metabolism is depressed in renal failure

  4. Brain tissue partial pressure of oxygen predicts the outcome of severe traumatic brain injury under mild hypothermia treatment

    Directory of Open Access Journals (Sweden)

    Sun H

    2016-08-01

    Full Text Available Hongtao Sun,1,* Maohua Zheng,2,* Yanmin Wang,1 Yunfeng Diao,1 Wanyong Zhao,1 Zhengjun Wei1 1Sixth Department of Neurosurgery, Affiliated Hospital of Logistics University of People’s Armed Police Force, Tianjin, 2Department of Neurosurgery, The First Hospital of Lanzhou University, Lanzhou, People’s Republic of China *These authors contributed equally to this work Objective: The aim of this study was to investigate the clinical significance and changes of brain tissue partial pressure of oxygen (PbtO2 in the course of mild hypothermia treatment (MHT for treating severe traumatic brain injury (sTBI. Methods: There were 68 cases with sTBI undergoing MHT. PbtO2, intracranial pressure (ICP, jugular venous oxygen saturation (SjvO2, and cerebral perfusion pressure (CPP were continuously monitored, and clinical outcomes were evaluated using the Glasgow Outcome Scale score. Results: Of 68 patients with sTBI, PbtO2, SjvO2, and CPP were obviously increased, but decreased ICP level was observed throughout the MHT. PbtO2 and ICP were negatively linearly correlated, while there was a positive linear correlation between PbtO2 and SjvO2. Monitoring CPP and SjvO2 was performed under normal circumstances, and a large proportion of patients were detected with low PbtO2. Decreased PbtO2 was also found after MHT. Conclusion: Continuous PbtO2 monitoring could be introduced to evaluate the condition of regional cerebral oxygen metabolism, thereby guiding the clinical treatment and predicting the outcome. Keywords: severe traumatic brain injury, hypothermia, brain tissue partial pressure of oxygen, therapy

  5. The cerebral metabolic ratio is not affected by oxygen availability during maximal exercise in humans

    DEFF Research Database (Denmark)

    Volianitis, S.; Fabricius-Bjerre, A.; Overgaard, A.;

    2008-01-01

    .2% during exercise with an inspired O(2) fraction of 0.17 and 0.30, respectively. Whilst the increase in a-v lactate difference was attenuated by manipulation of cerebral O(2) availability, the cerebral metabolic ratio was not affected significantly. During maximal rowing, the cerebral metabolic ratio...

  6. Improved light collection and wavelet de-noising enable quantification of cerebral blood flow and oxygen metabolism by a low-cost, off-the-shelf spectrometer

    Science.gov (United States)

    Diop, Mamadou; Wright, Eric; Toronov, Vladislav; Lee, Ting-Yim; St. Lawrence, Keith

    2014-05-01

    Broadband continuous-wave near-infrared spectroscopy (CW-NIRS) is an attractive alternative to time-resolved and frequency-domain techniques for quantifying cerebral blood flow (CBF) and oxygen metabolism in newborns. However, efficient light collection is critical to broadband CW-NIRS since only a small fraction of the injected light emerges from any given area of the scalp. Light collection is typically improved by optimizing the contact area between the detection system and the skin by means of light guides with large detection surface. Since the form-factor of these light guides do not match the entrance of commercial spectrometers, which are usually equipped with a narrow slit to improve their spectral resolution, broadband NIRS spectrometers are typically custom-built. Nonetheless, off-the-shelf spectrometers have attractive advantages compared to custom-made units, such as low cost, small footprint, and wide availability. We demonstrate that off-the-shelf spectrometers can be easily converted into suitable instruments for deep tissue spectroscopy by improving light collection, while maintaining good spectral resolution, and reducing measurement noise. The ability of this approach to provide reliable cerebral hemodynamics was illustrated in a piglet by measuring CBF and oxygen metabolism under different anesthetic regimens.

  7. Matrix metalloproteinase-9 and tissue inhibitor of metalloproteinase-1 expression in early focal cerebral infarction following urokinase thrombolysis in rats

    Institute of Scientific and Technical Information of China (English)

    Yuqiang Song; Hongli Zou; Guofeng Wang; Hongxia Yang; Zhaohong Xie; Jianzhong Bi

    2012-01-01

    Activity of matrix metalloproteinase-9 increases following cerebral ischemia/reperfusion, and is associated with cerebral microvascular permeability, blood-brain barrier destruction, inflammatory cell infiltration and brain edema. Matrix metalloproteinase-9 also likely participates in thrombolysis. A rat model of middle cerebral artery infarction was established by injecting autologous blood clots into the internal carotid artery. At 3 hours following model induction, urokinase was injected into the caudal vein. Decreased neurological severity score, reduced infarct volume, and increased expression of matrix metalloproteinase-9 and tissue inhibitor of metalloproteinase-1 were observed in the cerebral cortex 24 hours after urokinase thrombolysis. These results suggest that urokinase can suppress damage in the acute-early stage of cerebral infarction.

  8. Effects of race and sex on cerebral hemodynamics, oxygen delivery and blood flow distribution in response to high altitude

    Science.gov (United States)

    Liu, Jie; Liu, Yang; Ren, Li-Hua; Li, Li; Wang, Zhen; Liu, Shan-Shan; Li, Su-Zhi; Cao, Tie-Sheng

    2016-08-01

    To assess racial, sexual, and regional differences in cerebral hemodynamic response to high altitude (HA, 3658 m). We performed cross-sectional comparisons on total cerebral blood flow (TCBF = sum of bilateral internal carotid and vertebral arterial blood flows = QICA + QVA), total cerebrovascular resistance (TCVR), total cerebral oxygen delivery (TCOD) and QVA/TCBF (%), among six groups of young healthy subjects: Tibetans (2-year staying) and Han (Han Chinese) at sea level, Han (2-day, 1-year and 5-year) and Tibetans at HA. Bilateral ICA and VA diameters and flow velocities were derived from duplex ultrasonography; and simultaneous measurements of arterial pressure, oxygen saturation, and hemoglobin concentration were conducted. Neither acute (2-day) nor chronic (>1 year) responses showed sex differences in Han, except that women showed lower TCOD compared with men. Tibetans and Han exhibited different chronic responses (percentage alteration relative to the sea-level counterpart value) in TCBF (‑17% vs. 0%), TCVR (22% vs. 12%), TCOD (0% vs. 10%) and QVA/TCBF (0% vs. 2.4%, absolute increase), with lower resting TCOD found in SL- and HA-Tibetans. Our findings indicate racial but not sex differences in cerebral hemodynamic adaptations to HA, with Tibetans (but not Han) demonstrating an altitude-related change of CBF distribution.

  9. Reduced cerebral blood flow and oxygen metabolism in extremely preterm neonates with low-grade germinal matrix- intraventricular hemorrhage

    Science.gov (United States)

    Lin, Pei-Yi; Hagan, Katherine; Fenoglio, Angela; Grant, P. Ellen; Franceschini, Maria Angela

    2016-05-01

    Low-grade germinal matrix-intraventricular hemorrhage (GM-IVH) is the most common complication in extremely premature neonates. The occurrence of GM-IVH is highly associated with hemodynamic instability in the premature brain, yet the long-term impact of low-grade GM-IVH on cerebral blood flow and neuronal health have not been fully investigated. We used an innovative combination of frequency-domain near infrared spectroscopy and diffuse correlation spectroscopy (FDNIRS-DCS) to measure cerebral oxygen saturation (SO2) and an index of cerebral blood flow (CBFi) at the infant’s bedside and compute an index of cerebral oxygen metabolism (CMRO2i). We enrolled twenty extremely low gestational age (ELGA) neonates (seven with low-grade GM-IVH) and monitored them weekly until they reached full-term equivalent age. During their hospital stay, we observed consistently lower CBFi and CMRO2i in ELGA neonates with low-grade GM-IVH compared to neonates without hemorrhages. Furthermore, lower CBFi and CMRO2i in the former group persists even after the resolution of the hemorrhage. In contrast, SO2 does not differ between groups. Thus, CBFi and CMRO2i may have better sensitivity than SO2 in detecting GM-IVH-related effects on infant brain development. FDNIRS-DCS methods may have clinical benefit for monitoring the evolution of GM-IVH, evaluating treatment response, and potentially predicting neurodevelopmental outcome.

  10. 置氧法治疗对老年慢性硬膜下血肿患者脑组织结构和功能的保护作用%Protective effect of oxygen-exchange therapy on cerebral tissue structure and function in the elderly with chronic subdural hematoma

    Institute of Scientific and Technical Information of China (English)

    董欣明; 袁玉会; 潘蔚然; 王成林

    2005-01-01

    into the needle guard to cause the blood discharged from hematom again. Oxygen was perfused repetitively, once for 10 mL, till there was no blood flow. Finally, 10 mL oxygen was perfused following moving of trochar and bandaging.Oxygen volume used in each case was recorded. After operation,the volume of normal saline infusion could be increased as large as possible. The duration of infusion was 2 weeks.MAIN OUTCOME MEASURES: Improvement in limb function.RESULTS: All the patients were involved in the result analysis.①Within 24 hours, volume of hematomwas decreased obviously detected with CT, and hematom completely disappeared in 3 cases,which was replaced by oxygen. Three weeks later, all the oxygen was absorbed, the structure of midline was symmetrical and the form of brain ventricles was normal. No pain was found and 5 casesof limb asthenia were also recovered. ②Advantage and disadvantage of foramen-vertebrate oxygen-exchange operation: Advantages were listed as follows: It was simple and spent shorter time,there were few complications, and patients had no limitation in movement after operation. The operation avoided the occurrence of thrombosis of lower limbs. Cranial pressure could not lower quickly. As the pressure resident in envelope, cerebraospinal fluid could not move into the envelope. Along with the absorption of oxygen,hematom was decreased gradually till completely disappeared. Occurrence of clinical symptoms resulting from cerebral blood perfusion was decreased so as to draw rein. The disadvantage of this operation was that it was not suitable for heart disease patients to undertake this operation at bedside, and headache or limb asthenia could not be alleviated immediately.CONCLUSION: The new operation-method of cranial foramen-vertebrate oxygen-exchange to treat chronic subdural hemtoma in the elderly is safe, reliable and feasible through preoperative CT localization.%背景:老年慢性硬膜下血肿以往均采用传统的颅骨钻孔冲洗引

  11. Brazilein inhibits neuronal inflammation induced by cerebral ischemia and oxygen-glucose deprivation through targeting NOD2 expression.

    Science.gov (United States)

    Yan, Xiao-Jin; Chai, Yu-Shuang; Yuan, Zhi-Yi; Wang, Xin-Pei; Jiang, Jing-Fei; Lei, Fan; Xing, Dong-Ming; DU, Li-Jun

    2016-05-01

    Brazilein is reported to have immunosuppressive effect on cardiovascular and cerebral-vascular diseases. The essential roles of innate immunity in cerebral ischemia are increasingly identified, but no studies concerning the influence of brazilein on the innate immunity receptors have been reported. The present study was designed to investigate the regulation of NOD2 (Nucleotide-binding oligomerization domain-containing protein 2) by brazilein for its protection of neuron in cerebral ischemia in vivo and oxygen-glucose deprivation in vitro. The results showed that brazilein could reverse the elevated expression of NOD2 and TNFα (tumor necrosis factor alpha) elicited by cerebral ischemia and reperfusion. This reduction could also be detected in normal mice and C17.2 cells, indicating that this suppressive effect of brazilein was correlated with NOD2. The results from GFP reporter plasmid assay suggested brazilein inhibited NOD2 gene transcription. In conclusion, brazilein could attenuate NOD2 and TNFα expression in cerebral ischemia and NOD2 may be one possible target of brazilein for its immune suppressive effect in neuro-inflammation.

  12. 高压氧治疗脑梗死疗效观察%Observation of therapeutic effect of hyperbaric oxygen on cerebral infarction

    Institute of Scientific and Technical Information of China (English)

    马维艳; 杨丽

    2002-01-01

    Background:Hypoxia and ischemia resulting from cerebral infarction can further cause a series of pathological changes such as hydrocephallus.Drug therapy can improve cerebral blood circulation and enhance flow volume and decrease infarction area.If hyperbaric oxygen is added,pathophysiological changes such as ischemia and hypoxia can be improved and normal metabolism of brain cells be restored.

  13. Wavelet analysis of cerebral oxygenation oscillations in the screening of Moyamoya disease.

    Science.gov (United States)

    He, Ying; Jiang, Pengjun; Han, Shanshan; Wang, Rong; Li, Yue; Teng, Yichao; Gao, Tianxin

    2014-01-01

    Near-infrared spectroscopy (NIRS) was used to investigate the cerebral oxygenation of Moyamoya and healthy subjects. Continuous recordings of NIRS signals for 20 min (20 min signals) were obtained from 17 healthy subjects (age: 37.4 ± 11.3) and 17 Moyamoya subjects (age: 40.1 ± 11.2). Spectral analysis based on wavelet transformation identified five frequency intervals (I, 0.0095 Hz to 0.02 Hz; II, 0.02 Hz to 0.06 Hz; III, 0.06 Hz to 0.15 Hz; IV, 0.15 Hz to 0.40 Hz; and V, 0.40 Hz to 2.00 Hz) in the 20 min signals and three frequency intervals (III, 0.06 Hz to 0.15 Hz; IV, 0.15 Hz to 0.40 Hz; and V, 0.40 Hz to 2.00 Hz) in the 3 min signals (the first 3 min signals were continuously extracted from the 20 min signals). Significant differences (p Moyamoya disease. As a potential screening method for Moyamoya disease, the simple threshold method exhibited 73.5% accuracy.

  14. Neurotrophin-3 promotes cell death induced in cerebral ischemia, oxygen-glucose deprivation, and oxidative stress: possible involvement of oxygen free radicals.

    Science.gov (United States)

    Bates, Brian; Hirt, Lorenz; Thomas, Sunu S; Akbarian, Schahram; Le, Dean; Amin-Hanjani, Sepideh; Whalen, Michael; Jaenisch, Rudolf; Moskowitz, Michael A

    2002-02-01

    To explore the role of neurotrophin-3 (NT-3) during cerebral ischemia, NT-3-deficient brains were subjected to transient focal ischemia. Conditional mutant brains produced undetectable amounts of NT-3 mRNA, whereas the expression of the neurotrophin, BDNF, the NT-3 receptor, TrkC, and the nonselective, low-affinity neurotrophin receptor p75NTR, were comparable to wild-type. Baseline absolute blood flow, vascular and neuroanatomical features, as well as physiological measurements were also indistinguishable from wild-type. Interestingly, the absence of NT-3 led to a significantly decreased infarct volume 23 h after middle cerebral artery occlusion. Consistent with this, the addition of NT-3 to primary cortical cell cultures exacerbated neuronal death caused by oxygen-glucose deprivation. Coincubation with the oxygen free radical chelator, trolox, diminished potentiation of neuronal death. NT-3 also enhanced neuronal cell death and the production of reactive oxygen species caused by oxidative damage inducing agents. We conclude that endogenous NT-3 enhanced neuronal injury during acute stroke, possible by increasing oxygen-radical mediated cell death.

  15. Implementing oxygen control in chip-based cell and tissue culture systems.

    Science.gov (United States)

    Oomen, Pieter E; Skolimowski, Maciej D; Verpoorte, Elisabeth

    2016-09-21

    Oxygen is essential in the energy metabolism of cells, as well as being an important regulatory parameter influencing cell differentiation and function. Interest in precise oxygen control for in vitro cultures of tissues and cells continues to grow, especially with the emergence of the organ-on-a-chip and the desire to emulate in vivo conditions. This was recently discussed in this journal in a Critical Review by Brennan et al. (Lab Chip (2014). DOI: ). Microfluidics can be used to introduce flow to facilitate nutrient supply to and waste removal from in vitro culture systems. Well-defined oxygen gradients can also be established. However, cells can quickly alter the oxygen balance in their vicinity. In this Tutorial Review, we expand on the Brennan paper to focus on the implementation of oxygen analysis in these systems to achieve continuous monitoring. Both electrochemical and optical approaches for the integration of oxygen monitoring in microfluidic tissue and cell culture systems will be discussed. Differences in oxygen requirements from one organ to the next are a challenging problem, as oxygen delivery is limited by its uptake into medium. Hence, we discuss the factors determining oxygen concentrations in solutions and consider the possible use of artificial oxygen carriers to increase dissolved oxygen concentrations. The selection of device material for applications requiring precise oxygen control is discussed in detail, focusing on oxygen permeability. Lastly, a variety of devices is presented, showing the diversity of approaches that can be employed to control and monitor oxygen concentrations in in vitro experiments.

  16. Variations of brain edema and neurological function of rat models of cerebral infarction after hyperbaric oxygen therapy%高压氧干预脑梗死模型大鼠脑水肿及神经功能变化

    Institute of Scientific and Technical Information of China (English)

    田烜

    2015-01-01

    背景:研究认为,高压氧有较好保护脑神经和脑细胞的作用,应用高压氧可使氧分压快速弥撒到相对缺氧的脑组织中,增加脑组织的血氧含量,促进脑水肿及脑神经功能的恢复。目的:观察大脑中动脉阻塞造模后高压氧干预对大鼠脑梗死组织水肿的影响,并探讨其对脑梗死大鼠神经功能保护的可能作用机制。方法:成年雌性SD大鼠65只,造模成功60只,随机区组法分为假手术组、脑梗死组、高压氧组,每组20只,按照线栓线法建立大鼠大脑中动脉阻塞脑梗死模型。造模后3 d,通过TUNEL法检测各实验组大鼠脑梗死区神经细胞的凋亡情况。伤后72 h通过RT-PCR、Western blot检测脑梗死区周围AQP4/9、基质金属蛋白酶9/2基因转录和蛋白的表达,通过苏木精-伊红染色观察脑梗死区病理组织形态学变化,通过免疫组织化学法检测胶质纤维酸性蛋白的表达量,高压氧干预后24 h,3 d及伤后1、2周行Longa行为学评分,检测神经功能的损伤情况。结果与结论:①高压氧组Longa行为学评分在治疗后1,2 d均较脑梗死组显著降低(P <0.05)。②造模后3 d高压氧组细胞凋亡指数均明显低于脑梗死组(P<0.05)。③造模后72 h,与脑梗死组相比高压氧组AQP4/9、基质金属蛋白酶9/2基因和蛋白表达均较显著降低(P<0.05)。结果提示高压氧治疗通过减少大鼠脑梗死区神经细胞的凋亡和降低脑组织水肿,对脑梗死起到保护作用。%BACKGROUND:Several studies have suggested that hyperbaric oxygen could better protect cranial nerve and brain cels. Hyperbaric oxygen therapy can make oxygen partial pressure rapidly diffusing toward relatively hypoxic brain tissue, so as to increase blood oxygen content in the brain tissue, reduce brain edema and promote the recovery of brain function. OBJECTIVE: To observe the effects of hyperbaric oxygen therapy on brain tissue

  17. Can the cerebral metabolic rate of oxygen be estimated with near-infrared spectroscopy?

    Science.gov (United States)

    Boas, D. A.; Strangman, G.; Culver, J. P.; Hoge, R. D.; Jasdzewski, G.; Poldrack, R. A.; Rosen, B. R.; Mandeville, J. B.

    2003-08-01

    We have measured the changes in oxy-haemoglobin and deoxy-haemoglobin in the adult human brain during a brief finger tapping exercise using near-infrared spectroscopy (NIRS). The cerebral metabolic rate of oxygen (CMRO2) can be estimated from these NIRS data provided certain model assumptions. The change in CMRO2 is related to changes in the total haemoglobin concentration, deoxy-haemoglobin concentration and blood flow. As NIRS does not provide a measure of dynamic changes in blood flow during brain activation, we relied on a Windkessel model that relates dynamic blood volume and flow changes, which has been used previously for estimating CMRO2 from functional magnetic resonance imaging (fMRI) data. Because of the partial volume effect we are unable to quantify the absolute changes in the local brain haemoglobin concentrations with NIRS and thus are unable to obtain an estimate of the absolute CMRO2 change. An absolute estimate is also confounded by uncertainty in the flow-volume relationship. However, the ratio of the flow change to the CMRO2 change is relatively insensitive to these uncertainties. For the finger tapping task, we estimate a most probable flow-consumption ratio ranging from 1.5 to 3 in agreement with previous findings presented in the literature, although we cannot exclude the possibility that there is no CMRO2 change. The large range in the ratio arises from the large number of model parameters that must be estimated from the data. A more precise estimate of the flow-consumption ratio will require better estimates of the model parameters or flow information, as can be provided by combining NIRS with fMRI.

  18. Protective effects of l-glutamine against toxicity of deltamethrin in the cerebral tissue

    Science.gov (United States)

    Varol, Sefer; Özdemir, Hasan Hüseyin; Çevik, Mehmet Uğur; Altun, Yaşar; Ibiloğlu, Ibrahim; Ekinci, Aysun; Ibiloğlu, Aslıhan Okan; Balduz, Metin; Arslan, Demet; Tekin, Recep; Aktar, Fesih; Aluçlu, Mehmet Ufuk

    2016-01-01

    Background Deltamethrin (DLM) is a broad-spectrum synthetic dibromo-pyrethroid pesticide that is widely used for agricultural and veterinary purposes. However, human exposure to the pesticide leads to neurotoxicity. Glutamine is one of the principal, free intracellular amino acids and may also be an antioxidant. This study was undertaken in order to examine the neuroprotective and antioxidant potential of l-glutamine against DLM toxicity in female Wistar albino rats. Materials and methods The rats were divided into the following groups (n=10): Group I: control (distilled water; 10 mL/kg, po one dose), Group II: l-glutamine (1.5 g/kg, po one dose), Group III: DLM (35 mg/kg, po one dose), and Group IV: DLM (35 mg/kg, po one dose) and l-glutamine (1.5 g/kg, po one dose after 4 hours). Total oxidant status (TOS), total antioxidant status (TAS), tumor necrosis factor-α, interleukin (IL)-1β, and IL-6 levels and apoptosis were evaluated in brain tissue. Results DLM-treated animals had a significant increase in brain biochemical parameters, as well as TOS and TAS. Furthermore, the histopathological examination showed neuronal cell degeneration in the cerebral tissue. l-Glutamine treatment decreased the elevated brain levels of TOS and neuronal cell degeneration. There was no difference in tumor necrosis factor-α, IL-1β, and IL-6 levels between the groups. Conclusion l-Glutamine may reduce the toxic effects of DLM in the cerebral tissue through antioxidant properties. PMID:27143900

  19. Effects of angiopoietin-1 on hemorrhagic transformation and cerebral edema after tissue plasminogen activator treatment for ischemic stroke in rats.

    Science.gov (United States)

    Kawamura, Kunio; Takahashi, Tetsuya; Kanazawa, Masato; Igarashi, Hironaka; Nakada, Tsutomu; Nishizawa, Masatoyo; Shimohata, Takayoshi

    2014-01-01

    An angiogenesis factor, angiopoietin-1 (Ang1), is associated with the blood-brain barrier (BBB) disruption after focal cerebral ischemia. However, whether hemorrhagic transformation and cerebral edema after tissue plasminogen activator (tPA) treatment are related to the decrease in Ang1 expression in the BBB remains unknown. We hypothesized that administering Ang1 might attenuate hemorrhagic transformation and cerebral edema after tPA treatment by stabilizing blood vessels and inhibiting hyperpermeability. Sprague-Dawley rats subjected to thromboembolic focal cerebral ischemia were assigned to a permanent ischemia group (permanent middle cerebral artery occlusion; PMCAO) and groups treated with tPA at 1 h or 4 h after ischemia. Endogenous Ang1 expression was observed in pericytes, astrocytes, and neuronal cells. Western blot analyses revealed that Ang1 expression levels on the ischemic side of the cerebral cortex were decreased in the tPA-1h, tPA-4h, and PMCAO groups as compared to those in the control group (P = 0.014, 0.003, and 0.014, respectively). Ang1-positive vessel densities in the tPA-4h and PMCAO groups were less than that in the control group (p = 0.002 and cerebral homogenate (p = 0.007) and cerebral edema due to BBB damage (p = 0.038), as compared to administering COMP protein alone. In conclusion, Ang1 might be a promising target molecule for developing vasoprotective therapies for controlling hemorrhagic transformation and cerebral edema after tPA treatment.

  20. Expression of IL-1 β and TNF-α in edematous cerebral tissues of rats after traumatic brain injury and the effect of hyperbaric oxygen on its expression%白细胞介素-1β和肿瘤坏死因子-α在脑外伤大鼠脑水肿组织中的表达及高压氧对其影响的研究

    Institute of Scientific and Technical Information of China (English)

    何俊德; 谢泽宇; 陈葆; 瞿文军

    2012-01-01

    目的 探讨脑外伤大鼠脑水肿组织中白细胞介-素-1β(IL-1β)和肿瘤坏死因子-α(TNF-α)的表达变化及不同时间窗高压氧(HBO)治疗对其表达的影响.方法 将96只大鼠随机分为:正常对照组(A组)、液压冲击脑外伤模型组(B组)、液压冲击脑外伤模型+常规治疗组(C组)、液压冲击脑外伤模型+常规治疗+ HBO 治疗组(D组),每组24只:D组模型建立后根据进行HBO治疗的时间点(3、12、24、72 h),分为4亚组(D-3 h组、D-12 h组、D-24h组和D-72 h组,每亚组6只),其中B、C、D组分别按照采用大鼠侧位液压冲击构建脑损伤动物模型后进行不同治疗.RT-PCR和免疫组化分别检测脑组织中IL-1β和TNF-a的mRNA表达和蛋白表达情况.结果 IL-1β3和TNF-α mRNA表达及蛋白表达方面A组<D-3 h组<D-12 h组<D-24 h组<D-72 b组<C组<B组(P均< 0.05).结论 IL-1β和TNF-α与脑外伤大鼠脑水肿组织的形成密切相关,HBO可以下调IL-β3和TNF-α的表达,减轻脑水肿,从而改善颅脑损伤大鼠的学习能力,而且这种高压氧治疗的时间宜尽早实施.%Objective To study the changes of expression of IL-1β and TNF-αt in edematous cerebral tissues of rats after traumatic brain injury and the effect of hyperbaric oxygen(HBO)on the expression.Methods The traumatic brain injury model was established by use of graded lateral fluid percussion in rats.Minty-six rats were randomly divided into 4 groups:control group(group A),traumatic brain injury group(group B),traumatic brain injury and conventional therapy group(group C),traumatic brain injury and conventional therapy and HBO therapy group(group D)(n =24).And group D were sub divided into 4 groups:group D-3 h,group D-12 h,group D-24 h and groups D-72 h that HBO therapy was administered at 3,12,24,72 h after traumatic brain injury(n =6).Cerebral IL-1β and TNF-α protein expression and mRNA expression were tested by immunohistochemistry and RT-PCR in each group after

  1. In vivo EPR oximetry using an isotopically-substituted nitroxide: Potential for quantitative measurement of tissue oxygen

    Science.gov (United States)

    Weaver, John; Burks, Scott R.; Liu, Ke Jian; Kao, Joseph P. Y.; Rosen, Gerald M.

    2016-10-01

    Variations in brain oxygen (O2) concentration can have profound effects on brain physiology. Thus, the ability to quantitate local O2 concentrations noninvasively in vivo could significantly enhance understanding of several brain pathologies. However, quantitative O2 mapping in the brain has proven difficult. The electron paramagnetic resonance (EPR) spectra of nitroxides are sensitive to molecular O2 and can be used to estimate O2 concentrations in aqueous media. We recently synthesized labile-ester-containing nitroxides, such as 3-acetoxymethoxycarbonyl-2,2,5,5-tetramethyl-1-pyrrolidinyloxyl (nitroxide 4), which accumulate in cerebral tissue after in situ hydrolysis, and thus enable spatial mapping of O2 concentrations in the mouse brain by EPR imaging. In an effort to improve O2 quantitation, we prepared 3-acetoxymethoxycarbonyl-2,2,5,5-tetra(2H3)methyl-1-(3,4,4-2H3,1-15N)pyrrolidinyloxyl (nitroxide 2), which proved to be a more sensitive probe than its normo-isotopic version for quantifying O2 in aqueous solutions of various O2 concentrations. We now demonstrate that this isotopically substituted nitroxide is ∼2-fold more sensitive in vivo than the normo-isotopic nitroxide 4. Moreover, in vitro and in vivo EPR spectral-spatial imaging results with nitroxide 2 demonstrate significant improvement in resolution, reconstruction and spectral response to local O2 concentrations in cerebral tissue. Thus, isotopic-substituted nitroxides, such as 2, are excellent sensors for in vivo O2 quantitation in tissues, such as the brain.

  2. Determination of oxygen tension in the subcutaneous tissue of cosmonauts during the Salyut-6 mission

    Science.gov (United States)

    Baranski, S.; Bloszczynski, R.; Hermaszewski, M.; Kubiczkowa, J.; Piorko, A.; Saganiak, R.; Sarol, Z.; Skibniewsky, F.; Stendera, J.; Walichnowski, W.

    1982-01-01

    A polarographic technique was used to measure the oxygen tension in subcutaneous tissue of the forearm of a cosmonaut prior to, after, and on the fourth day of a space mission performed by Salut-6. A drop in the oxygen exchange rate in the peripheral tissues during weightlessness was observed. The mechanisms of this change are studied, taking into consideration the blood distribution in the organism and microcirculation disorders reflected by a decreased blood flow rate in arterial-venous junctions.

  3. Implementing oxygen control in chip-based cell and tissue culture systems

    NARCIS (Netherlands)

    Oomen, Pieter; Skolimowski, Maciej; Verpoorte, Elisabeth

    2016-01-01

    Oxygen is essential in the energy metabolism of cells, as well as being an important regulatory parameter influencing cell differentiation and function. Interest in precise oxygen control for in vitro cultures of tissues and cells continues to grow, especially with the emergence of the organ-on-a-ch

  4. Monitoring tissue oxygen availability with near infrared spectroscopy (NIRS) in health and disease

    DEFF Research Database (Denmark)

    Boushel, R; Langberg, Henning; Olesen, J

    2001-01-01

    Near infrared spectroscopy (NIRS) is becoming a widely used research instrument to measure tissue oxygen (O2) status non-invasively. Continuous-wave spectrometers are the most commonly used devices, which provide semi-quantitative changes in oxygenated and deoxygenated hemoglobin in small blood v...

  5. LOCALISED MUSCLE TISSUE OXYGENATION DURING DYNAMIC EXERCISE WITH WHOLE BODY VIBRATION

    Directory of Open Access Journals (Sweden)

    Daniel Robbins

    2012-06-01

    Full Text Available Despite increasing use of whole body vibration during exercise an understanding of the exact role of vibration and the supporting physiological mechanisms is still limited. An important aspect of exercise analysis is the utilisation of oxygen, however, there have been limited studies considering tissue oxygenation parameters, particularly during dynamic whole body vibration (WBV exercise. The aim of this study was to determine the effect of adding WBV during heel raise exercises and assessing changes in tissue oxygenation parameters of the lateral gastrocnemius using Near Infra Red Spectroscopy (NIRS. Twenty healthy subjects completed ten alternating sets of 15 heel raises (vibration vs. no vibration. Synchronous oxygenation and motion data were captured prior to exercise to determine baseline levels, for the duration of the exercise and 20 sec post exercise for the recovery period. Both vibration and no vibration conditions elicited a characteristic increase in deoxyhaemoglobin and decreases in oxyhaemoglobin, total haemoglobin, tissue oxygenation index and normalised tissue haemoglobin index which are indicative of local tissue hypoxia. However, the addition of vibration elicited significantly lower (p < 0. 001 depletions in oxyhaemoglobin, total haemoglobin, normalised tissue haemoglobin index but no significant differences in deoxyhaemoglobin. These findings suggest that addition of vibration to exercise does not increase the cost of the exercise for the lateral gastrocnemius muscle, but does decrease the reduction in local muscle oxygenation parameters, potentially resulting from increased blood flow to the calf or a vasospastic response in the feet. However, further studies are needed to establish the mechanisms underlying these findings

  6. Effect of oxygen breathing on micro oxygen bubbles in nitrogen-depleted rat adipose tissue at sea level and 25 kPa altitude exposures

    DEFF Research Database (Denmark)

    Randsoe, Thomas; Hyldegaard, Ole

    2012-01-01

    The standard treatment of altitude decompression sickness (aDCS) caused by nitrogen bubble formation is oxygen breathing and recompression. However, micro air bubbles (containing 79% nitrogen), injected into adipose tissue, grow and stabilize at 25 kPa regardless of continued oxygen breathing...... and the tissue nitrogen pressure. To quantify the contribution of oxygen to bubble growth at altitude, micro oxygen bubbles (containing 0% nitrogen) were injected into the adipose tissue of rats depleted from nitrogen by means of preoxygenation (fraction of inspired oxygen = 1.0; 100%) and the bubbles studied...... prebreathing at 101.3 kPa (sea level). Micro oxygen bubbles of 500-800 nl were then injected into the exposed abdominal adipose tissue. The oxygen bubbles were studied for up to 3.5 h during continued oxygen breathing at either 101.3 or 25 kPa ambient pressures. At 101.3 kPa, all bubbles shrank consistently...

  7. Coupling of cerebral blood flow and oxygen metabolism is conserved for chromatic and luminance stimuli in human visual cortex.

    Science.gov (United States)

    Leontiev, Oleg; Buracas, Giedrius T; Liang, Christine; Ances, Beau M; Perthen, Joanna E; Shmuel, Amir; Buxton, Richard B

    2013-03-01

    The ratio of the changes in cerebral blood flow (CBF) and cerebral metabolic rate of oxygen (CMRO(2)) during brain activation is a critical determinant of the magnitude of the blood oxygenation level dependent (BOLD) response measured with functional magnetic resonance imaging (fMRI). Cytochrome oxidase (CO), a key component of oxidative metabolism in the mitochondria, is non-uniformly distributed in visual area V1 in distinct blob and interblob regions, suggesting significant spatial variation in the capacity for oxygen metabolism. The goal of this study was to test whether CBF/CMRO(2) coupling differed when these subpopulations of neurons were preferentially stimulated, using chromatic and luminance stimuli to preferentially stimulate either the blob or interblob regions. A dual-echo spiral arterial spin labeling (ASL) technique was used to measure CBF and BOLD responses simultaneously in 7 healthy human subjects. When the stimulus contrast levels were adjusted to evoke similar CBF responses (mean 65.4% ± 19.0% and 64.6% ± 19.9%, respectively for chromatic and luminance contrast), the BOLD responses were remarkably similar (1.57% ± 0.39% and 1.59% ± 0.35%) for both types of stimuli. We conclude that CBF-CMRO(2) coupling is conserved for the chromatic and luminance stimuli used, suggesting a consistent coupling for blob and inter-blob neuronal populations despite the difference in CO concentration.

  8. The Effect of Equal Ratio Ventilation on Oxygenation, Respiratory Mechanics, and Cerebral Perfusion Pressure During Laparoscopy in the Trendelenburg Position.

    Science.gov (United States)

    Jo, Youn Yi; Kim, Ji Young; Chang, Young Jin; Lee, Sehwan; Kwak, Hyun Jeong

    2016-06-01

    The aim of this study was to investigate the effects of equal ratio ventilation (ERV) on oxygenation, respiratory mechanics, and the cerebral perfusion pressure during pneumoperitoneum in the Trendelenburg position. Thirty patients undergoing laparoscopic low anterior resection (25 to 65 y) were enrolled. Mechanical ventilator was set to volume-controlled mode at an inspiratory to expiratory (I:E) ratio of 1:2 with a tidal volume of 8 mL/kg of ideal body weight with a 5 cm H2O positive end-expiratory pressure. Twenty minutes after pneumoperitoneum in the Trendelenburg position, the I:E ratio was changed to 1:1 for 20 minutes and then restored to 1:2. No significant changes in arterial oxygen tension and respiratory compliance after adopting ERV. Mean arterial pressure and cerebral perfusion pressure decreased significantly over time after adopting the Trendelenburg position during pneumoperitoneum (P=0.014 and 0.005, respectively). In conclusion, there was no improvement in oxygenation or respiratory mechanics with ERV.

  9. Eigenspectra optoacoustic tomography achieves quantitative blood oxygenation imaging deep in tissues

    CERN Document Server

    Tzoumas, Stratis; Olefir, Ivan; Stangl, Stefan; Symvoulidis, Panagiotis; Glasl, Sarah; Bayer, Christine; Multhoff, Gabriele; Ntziachristos, Vasilis

    2015-01-01

    Light propagating in tissue attains a spectrum that varies with location due to wavelength-dependent fluence attenuation by tissue optical properties, an effect that causes spectral corruption. Predictions of the spectral variations of light fluence in tissue are challenging since the spatial distribution of optical properties in tissue cannot be resolved in high resolution or with high accuracy by current methods. Spectral corruption has fundamentally limited the quantification accuracy of optical and optoacoustic methods and impeded the long sought-after goal of imaging blood oxygen saturation (sO2) deep in tissues; a critical but still unattainable target for the assessment of oxygenation in physiological processes and disease. We discover a new principle underlying light fluence in tissues, which describes the wavelength dependence of light fluence as an affine function of a few reference base spectra, independently of the specific distribution of tissue optical properties. This finding enables the introd...

  10. Effect of sevoflurane and propofol on cerebral oxygen metabolism in cardiopulmonary bypass and postoperative neurological function injury

    Institute of Scientific and Technical Information of China (English)

    Zhu Zhu; Wei-Wei Li

    2016-01-01

    Objective:To study the effect of sevoflurane and propofol on cerebral oxygen metabolism in cardiopulmonary bypass (CPB) and postoperative neurological function injury.Methods:A total of 48 cases of patients who received mitral valve replacement under CPB in our hospital were selected and randomly divided into sevoflurane group (S group) and propofol group (P group) who received sevoflurane-based intravenous inhalational anesthesia and propofol-based total intravenous anesthesia respectively, cerebral oxygen metabolism indexes were determined before CPB started (T0), when nasopharyngeal temperature fell to a constant low temperature (T1), when CPB ended (T2) and 1 h after CPB ended (T3) respectively during operation, and serum neurological function, cardiac function and liver function injury molecules were determined after operation.Results: Intraoperative SjvO2, AVDO2, O2ER and rSO2 were not significantly different between two groups, SjvO2 at T1 significantly increased, AVDO2 and O2ER significantly decreased and rSO2 didn’t change significantly, SjvO2 at T2 significantly decreased, AVDO2 and O2ER significantly increased and rSO2 didn’t change significantly; postoperative serum NSE, S100β, Aβ, Glu, Asp and Gly levels of S group were significantly lower than those of P group, and CK-MB, LDH, cTnI, ALT and AST levels were not significantly different from those of P group.Conclusion:Both sevoflurane and propofol can maintain the balance of cerebral oxygen metabolism in mitral valve replacement under CPB and protect the cardiac function and liver function, but sevoflurane has more ideal protective effect on postoperative neurological function.

  11. Experimental Study on the Expression of HIF-1α and Its Relationship to Apoptosis in Tissues around Cerebral Bleeding Loci

    Institute of Scientific and Technical Information of China (English)

    朱遂强; 唐洲平; 郭守刚; 彭岚; 方思羽; 张苏明

    2004-01-01

    The expression of hypoxia inducible factor-1 alpha (HIF-1α) and its relationship to apoptosis in tissues around cerebral bleeding loci was studied. The expression of HIF-1α and apoptosis in 37 samples of tissues around cerebral bleeding loci and 9 samples of normal cerebral tissues was assessed by immunohistochemical straining and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling methods. In 37 tissue samples around cerebral bleeding loci, the positive rate of the HIF-1α expression was 40.6 %. Especially in the patients with amount of bleeding>60 ml, the positive rate (88.9 %) of the HIF-1α expression was significantly higher than those with the amount of bleeding ranging from 30-45 ml or 45-60 ml (P<0.05). The expression of HIF-1α was increased as the amount of bleeding and operative time increased (P<0.05). There existed a positive correlation between HIF-1α labeling index and apoptosis index (n= 12, r= 0.56, P<0.01). These results suggested that the expression of HIF-1α was closely related with the time of hemorrhage and the amount of bleeding, and could induce the apoptosis of neurons.

  12. Monitoring tissue oxygen availability with near infrared spectroscopy (NIRS) in health and disease

    DEFF Research Database (Denmark)

    Boushel, Robert Christopher; Langberg, H; Olesen, J

    2001-01-01

    Near infrared spectroscopy (NIRS) is becoming a widely used research instrument to measure tissue oxygen (O2) status non-invasively. Continuous-wave spectrometers are the most commonly used devices, which provide semi-quantitative changes in oxygenated and deoxygenated hemoglobin in small blood...... vessels (arterioles, capillaries and venules). Refinement of NIRS hardware and the algorithms used to deconvolute the light absorption signal have improved the resolution and validity of cytochrome oxidase measurements. NIRS has been applied to measure oxygenation in a variety of tissues including muscle...

  13. Evaluation of Hypoxic Tissue Dynamics with F-18-FMISO PET in a Rat Model of Permanent Cerebral Ischemia

    OpenAIRE

    Rojas, Santiago; Herance, José Raul; Abad, Sergio; Jiménez, Xavier; Pareto, Deborah; Ruiz, Alba; Torrent, Èlia; Figueiras, Francisca P.; Popota, Foteini; Fernández-Soriano, Francisco J.; Planas, Anna M; Gispert, Juan D.

    2011-01-01

    Purpose: [18F]Fluoromisonidazole (18F-FMISO) is a nitroimidazole derivative that has been proposed as a positron emission tomography (PET) radiotracer to detect hypoxic tissue in vivo. This compound accumulates in hypoxic but viable tissue and may be a good candidate for evaluating the ischemic penumbra. We evaluated the time course of 18F-FMISO uptake using PET in a rat model of permanent cerebral ischemia and the correlation with histological changes. Procedures: Rats (n = 14) were subjecte...

  14. Dissolution of emboli in rats with experimental cerebral thromboembolism by recombinant human tissue plasminogen activator (TD-2061)

    Energy Technology Data Exchange (ETDEWEB)

    Hara, T.; Iwamoto, M.; Ogawa, H.; Yamamoto, A.; Tomikawa, M. (Research Institute, Daiichi Pharmaceutical Co., Ltd., Tokyo, (Japan))

    1990-08-15

    Tissue plasminogen activator (t-PA) is frequently administered clinically as thrombolytic therapy. We injected recombinant t-PA into rats with cerebral {sup 125}I-labeled blood clot emboli to evaluate the dissolutive effect of recombinant human single-chain t-PA (rt-PA; TD-2061) on such emboli and to examine the possibility of improving neurological damage in patients with cerebral thrombosis. When rt-PA was given intravenously at a dose of 350,000 IU/kg 2 minutes before embolization, radioactivity in the affected cerebral hemisphere decreased to 20% of that in the vehicle control 2 hours after embolization. A significant decrease in radioactivity in the cerebral hemisphere was also found on the administration of 700,000 IU/kg of rt-PA 30 or 60 minutes after embolization, but not when rt-PA was administered 2 minutes after embolization. Marked inhibition of abnormal behavior such as hemiplegia was seen on treatment with rt-PA 2 minutes before embolization, but not at all when rt-PA treatment was given 30 or 60 minutes after embolization. The findings suggest that rt-PA can dissolve blood clot emboli in cerebral vessels and that prompt thrombolytic therapy is important to minimize neurological dysfunction in cases of cerebral thromboembolism.

  15. Diastolic myocardial dysfunction by tissue Doppler imaging predicts mortality in patients with cerebral infarction

    DEFF Research Database (Denmark)

    Olsen, Flemming J; Jørgensen, Peter G; Møgelvang, Rasmus;

    2015-01-01

    with cerebral infarction. Two hundred forty-four patients with cerebral infarction and subsequent echocardiographic examination in sinus rhythm were identified. Using TDI in three apical projections, longitudinal mitral annular velocities were obtained in six segments. Cox regression models, C...

  16. Ultrastructure of focal cerebral cortex tissue from rats with focal cortical dysplasia

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    BACKGROUND:Developing a model of focal cortical dysplasia in microgyrus and observing the ultrastructure of focal tissue is of important significance for analyzing the pathology of cortical developmental disorder and the factors of structural changes. OBJECTIVE:This study was to observe the pathological characteristics of focal tissue around the microgyrus of rats with cortical developmental disorder using an electron microscope,so as to analyze the causes associated with cerebral cortical developmental disorder. DESIGN:A randomized controlled animal experiment. SETTING:The First Affiliated Hospital of Chongqing Medical University. MATERIALS:This study was carried out in the Chongqing Key Laboratory of Neurology,Room for Electron Microscope of Chongqing Medical University,and Laboratory Animal Center,Research Institute of Surgery,Daping Hospital,Third Military Medical University of Chinese PLA between January 2004 and August 2006.Eighteen healthy newborn male Wistar rats,weighing 3.0 - 6.0 g,provided by the Laboratory Animal Center,Daping Hospital,Third Military Medical University of Chinese PLA,were involved in this study.The protocol was carried out in accordance with animal ethics guidelines for the use and care of animals.Probes (Chongqing Wire & Cable Factory,China) were made of copper core wire with diameter of 1 mm.METHODS:The rats were randomly divided into 3 groups with 6 in each:normal control group,liquid nitrogen injured group and sham-operation group.①In the liquid nitrogen injured group,a blunt probe frozen by liquid nitrogen was placed on fronto-parietal crinial bone of rats for 8 s.A 3 - 5 cm of microgyrus was induced in the unilateral cerebral sensory cortical area.In the sham-operation group,probe was placed at the room temperature.In the normal control group,rats were untouched.② The conscious state and electrical activity of brain of rats in each group were observed.③ 2-3 mm thickness of hippocampal tissue with coronary section was taken

  17. Tissue Oxygenation Monitoring using Resonance Raman Spectroscopy during Hemorrhage

    Science.gov (United States)

    2013-12-27

    by the fact that young swine are highly susceptible to iron-deficient anemia secondary to low tissue stores at birth and extremely rapid growth.40 The...venous oximetry and shock index in the emergency department: use in the evaluation of clinical shock. Am J Emerg Med. 1992;10:538 541. 38. Rivers EP

  18. Quasi-simultaneous multimodal imaging of cutaneous tissue oxygenation and perfusion

    Science.gov (United States)

    Ren, Wenqi; Gan, Qi; Wu, Qiang; Zhang, Shiwu; Xu, Ronald

    2015-12-01

    Simultaneous and quantitative assessment of multiple tissue parameters may facilitate more effective diagnosis and therapy in many clinical applications, such as wound healing. However, existing wound assessment methods are typically subjective and qualitative, with the need for sequential data acquisition and coregistration between modalities, and lack of reliable standards for performance evaluation or calibration. To overcome these limitations, we developed a multimodal imaging system for quasi-simultaneous assessment of cutaneous tissue oxygenation and perfusion in a quantitative and noninvasive fashion. The system integrated multispectral and laser speckle imaging technologies into one experimental setup. Tissue oxygenation and perfusion were reconstructed by advanced algorithms. The accuracy and reliability of the imaging system were quantitatively validated in calibration experiments and a tissue-simulating phantom test. The experimental results were compared with a commercial oxygenation and perfusion monitor. Dynamic detection of cutaneous tissue oxygenation and perfusion was also demonstrated in vivo by a postocclusion reactive hyperemia procedure in a human subject and a wound healing process in a wounded mouse model. Our in vivo experiments not only validated the performance of the multimodal imaging system for cutaneous tissue oxygenation and perfusion imaging but also demonstrated its technical potential for wound healing assessment in clinical practice.

  19. Protective effects of L-glutamine against toxicity of deltamethrin in the cerebral tissue

    Directory of Open Access Journals (Sweden)

    Varol S

    2016-04-01

    Full Text Available Sefer Varol, Hasan Hüseyin Özdemir, Mehmet Uğur Çevik, Yaşar Altun, Ibrahim Ibiloğlu, Aysun Ekinci, Aslıhan Okan Ibiloğlu, Metin Balduz, Demet Arslan, Recep Tekin, Fesih Aktar, Mehmet Ufuk Aluçlu Department of Neurology, Faculty of Medicine, Dicle University, Diyarbakir, Turkey Background: Deltamethrin (DLM is a broad-spectrum synthetic dibromo-pyrethroid pesticide that is widely used for agricultural and veterinary purposes. However, human exposure to the pesticide leads to neurotoxicity. Glutamine is one of the principal, free intracellular amino acids and may also be an antioxidant. This study was undertaken in order to examine the neuroprotective and antioxidant potential of L-glutamine against DLM toxicity in female Wistar albino rats. Materials and methods: The rats were divided into the following groups (n=10: Group I: control (distilled water; 10 mL/kg, po one dose, Group II: L-glutamine (1.5 g/kg, po one dose, Group III: DLM (35 mg/kg, po one dose, and Group IV: DLM (35 mg/kg, po one dose and L-glutamine (1.5 g/kg, po one dose after 4 hours. Total oxidant status (TOS, total antioxidant status (TAS, tumor necrosis factor-α, interleukin (IL-1β, and IL-6 levels and apoptosis were evaluated in brain tissue. Results: DLM-treated animals had a significant increase in brain biochemical parameters, as well as TOS and TAS. Furthermore, the histopathological examination showed neuronal cell degeneration in the cerebral tissue. L-Glutamine treatment decreased the elevated brain levels of TOS and neuronal cell degeneration. There was no difference in tumor necrosis factor-α, IL-1β, and IL-6 levels between the groups. Conclusion: L-Glutamine may reduce the toxic effects of DLM in the cerebral tissue through antioxidant properties. Keywords: deltamethrin, L-glutamine, rat

  20. The preliminary study of Ultraviolet-Irradiated and Oxygenated Blood Transfusion Therapy(UOBT) for Experimental Cerebral Infarction of Animal Brain Model

    Institute of Scientific and Technical Information of China (English)

    Su Xiu-Chu; Feng You-Qi; Zhou gang; Wu jun-yi

    2000-01-01

    In this presented study, we have developed a photochemical model of cerebral in farction in rabbit with stable and reproducible infarct size and extent. This model is similar to the pathological changes in human cerebral infarction. Using this model, therapeutic effects and mechanisms of UOBT on brain ischemic injury were invetigated in rabbits following the photochemical infarcnon The results showed that UOBT could significantly reduce the mtarcted size, and improve the cerebral blood flow compared with the control animals treated with non-u-radiated ad non-oxygenated blood transfusion. These data suggest that the UOBT may have a therapeutic potential for clinical rehabilitation effect in stroke treatment

  1. Oxygen supply to the fetal cerebral circulation in hypoplastic left heart syndrome: a simulation study based on the theoretical models of fetal circulation.

    Science.gov (United States)

    Sakazaki, Sayaka; Masutani, Satoshi; Sugimoto, Masaya; Tamura, Masanori; Kuwata, Seiko; Kurishima, Clara; Saiki, Hirofumi; Iwamoto, Yoichi; Ishido, Hirotaka; Senzaki, Hideaki

    2015-03-01

    Hypoxia due to congenital heart diseases (CHDs) adversely affects brain development during the fetal period. Head circumference at birth is closely associated with neuropsychiatric development, and it is considerably smaller in newborns with hypoplastic left heart syndrome (HLHS) than in normal newborns. We performed simulation studies on newborns with CHD to evaluate the cerebral circulation during the fetal period. The oxygen saturation of cerebral blood flow in newborns with CHD was simulated according to a model for normal fetal circulation in late pregnancy. We compared the oxygen saturation of cerebral blood flow between newborns with tricuspid atresia (TA; a disease showing univentricular circulation and hypoplasia of the right ventricle), those with transposition of the great arteries (TGA; a disease showing abnormal mixing of arterial and venous blood), and those with HLHS. The oxygen saturation of cerebral blood flow in newborns with normal circulation was 75.7 %, whereas it was low (49.5 %) in both newborns with HLHS and those with TA. Although the oxygen level is affected by the blood flow through the foramen ovale, the oxygen saturation in newborns with TGA was even lower (43.2 %). These data, together with previous reports, suggest that the cerebral blood flow rate is decreased in newborns with HLHS, and the main cause was strongly suspected to be retrograde cerebral perfusion through a patent ductus arteriosus. This study provides important information about the neurodevelopmental prognosis of newborns with HLHS and suggests the need to identify strategies to resolve this unfavorable cerebral circulatory state in utero.

  2. Restoration of Normal Cerebral Oxygen Consumption with Rapamycin Treatment in a Rat Model of Autism-Tuberous Sclerosis.

    Science.gov (United States)

    Chi, Oak Z; Wu, Chang-Chih; Liu, Xia; Rah, Kang H; Jacinto, Estela; Weiss, Harvey R

    2015-09-01

    Tuberous sclerosis (TSC) is associated with autism spectrum disorders and has been linked to metabolic dysfunction and unrestrained signaling of the mammalian target of rapamycin (mTOR). Inhibition of mTOR by rapamycin can mitigate some of the phenotypic abnormalities associated with TSC and autism, but whether this is due to the mTOR-related function in energy metabolism remains to be elucidated. In young Eker rats, an animal model of TSC and autism, which harbors a germ line heterozygous Tsc2 mutation, we previously reported that cerebral oxygen consumption was pronouncedly elevated. Young (4 weeks) male control Long-Evans and Eker rats were divided into control and rapamycin-treated (20 mg/kg once daily for 2 days) animals. Cerebral regional blood flow ((14)C-iodoantipyrine) and O2 consumption (cryomicrospectrophotometry) were determined in isoflurane-anesthetized rats. We found significantly increased basal O2 consumption in the cortex (8.7 ± 1.5 ml O2/min/100 g Eker vs. 2.7 ± 0.2 control), hippocampus, pons and cerebellum. Regional cerebral blood flow and cerebral O2 extractions were also elevated in all brain regions. Rapamycin had no significant effect on O2 consumption in any brain region of the control rats, but significantly reduced consumption in the cortex (4.1 ± 0.3) and all other examined regions of the Eker rats. Phosphorylation of mTOR and S6K1 was similar in the two groups and equally reduced by rapamycin. Thus, a rapamycin-sensitive, mTOR-dependent but S6K1-independent, signal led to enhanced oxidative metabolism in the Eker brain. We found decreased Akt phosphorylation in Eker but not Long-Evans rat brains, suggesting that this may be related to the increased cerebral O2 consumption in the Eker rat. Our findings suggest that rapamycin targeting of Akt to restore normal cerebral metabolism could have therapeutic potential in tuberous sclerosis and autism.

  3. Tissue-type plasminogen activator induces synaptic vesicle endocytosis in cerebral cortical neurons.

    Science.gov (United States)

    Yepes, M; Wu, F; Torre, E; Cuellar-Giraldo, D; Jia, D; Cheng, L

    2016-04-05

    The release of the serine proteinase tissue-type plasminogen activator (tPA) from the presynaptic terminal of cerebral cortical neurons plays a central role in the development of synaptic plasticity, adaptation to metabolic stress and neuronal survival. Our earlier studies indicate that by inducing the recruitment of the cytoskeletal protein βII-spectrin and voltage-gated calcium channels to the active zone, tPA promotes Ca(2+)-dependent translocation of synaptic vesicles (SVs) to the synaptic release site where they release their load of neurotransmitters into the synaptic cleft. Here we used a combination of in vivo and in vitro experiments to investigate whether this effect leads to depletion of SVs in the presynaptic terminal. Our data indicate that tPA promotes SV endocytosis via a mechanism that does not require the conversion of plasminogen into plasmin. Instead, we show that tPA induces calcineurin-mediated dynamin I dephosphorylation, which is followed by dynamin I-induced recruitment of the actin-binding protein profilin II to the presynaptic membrane, and profilin II-induced F-actin formation. We report that this tPA-induced sequence of events leads to the association of newly formed SVs with F-actin clusters in the endocytic zone. In summary, the data presented here indicate that following the exocytotic release of neurotransmitters tPA activates the mechanism whereby SVs are retrieved from the presynaptic membrane and endocytosed to replenish the pool of vesicles available for a new cycle of exocytosis. Together, these results indicate that in murine cerebral cortical neurons tPA plays a central role coupling SVs exocytosis and endocytosis.

  4. Tissue transglutaminase colocalizes with extracellular matrix proteins in cerebral amyloid angiopathy.

    Science.gov (United States)

    de Jager, Mieke; van der Wildt, Berend; Schul, Emma; Bol, John G J M; van Duinen, Sjoerd G; Drukarch, Benjamin; Wilhelmus, Micha M M

    2013-04-01

    Cerebral amyloid angiopathy (CAA) is a key histopathological hallmark of Alzheimer's disease (AD) and hereditary cerebral hemorrhage with amyloidosis of the Dutch type (HCHWA-D). CAA is characterized by amyloid-beta (Aβ) depositions and remodeling of the extracellular matrix (ECM) in brain vessels and plays an important role in the development and progression of both AD and HCHWA-D. Tissue transglutaminase (tTG) modulates the ECM by molecular cross-linking of ECM proteins. Here, we investigated the distribution pattern, cellular source, and activity of tTG in CAA in control, AD, and HCHWA-D cases. We observed increased tTG immunoreactivity and colocalization with Aβ in the vessel wall in early stage CAA, whereas in later CAA stages, tTG and its cross-links were present in halos enclosing the Aβ deposition. In CAA, tTG and its cross-links at the abluminal side of the vessel were demonstrated to be either of astrocytic origin in parenchymal vessels, of fibroblastic origin in leptomeningeal vessels, and of endothelial origin at the luminal side of the deposited Aβ. Furthermore, the ECM proteins fibronectin and laminin colocalized with the tTG-positive halos surrounding the deposited Aβ in CAA. However, we observed that in situ tTG activity was present throughout the vessel wall in late stage CAA. Together, our data suggest that tTG and its activity might play a differential role in the development and progression of CAA, possibly evolving from direct modulation of Aβ aggregation to cross-linking of ECM proteins resulting in ECM restructuring.

  5. 高压氧对急性脑梗死临床应用分析%CLINICAL APPLICATION OF HYPERBARIC OXYGENATION TO ACUTE CEREBRAL INFARCTION

    Institute of Scientific and Technical Information of China (English)

    邵伟波

    2002-01-01

    Objective:To determine the effect of hyperbaric oxygenation(HBO) on treating acute cerebral infarction(ACI). Methods: We randomly divided 60 patients with acute cerebral infarction into the treatment group and the control group. Hyperbaric oxygenation treatment was applied in the treatment group as routine drug therapy was used. The neurological function, living ability, clinical therapeutic effectiveness and hemorrheology changes of pa tients in the two groups before and after treatment were observed and evaluated. Results: The indexes of treatment were obviously improved one month after treatment (P < 0.05 ). Clinical effective rate was 93.3 % in this group,which was obviously higher than that of the control group(P < 0.05). Conclusion: Hyperbaric oxygenation can accelerate the recovery of neurological function of patients with acute cerebral infarction.

  6. Effect of hypertensive reperfusion on the changes between cerebral oxygen delivery and uptake after cardiac arrest and resuscitation in dogs

    Institute of Scientific and Technical Information of China (English)

    杜权; 马永达; 葛衡江; 刘怀琼; 李阳

    2004-01-01

    Objective: To study the changes between cerebral oxygen (O2) delivery and uptake in dogs resuscitated under normotension or hypertension for 4 h. Methods: The model of ventricular fibrillation of 8 min in 12 dogs was made,followed by open cardiopulmonary resuscitation, reperfnsion with normal or high mean arterial pressure (MAP), and controlled ventilation to 4 h. Animals were randomly assigned into Group NT (normotensive reperfusion, n = 6) and Group HT(hypertensive reperfusion, n = 6). Cerebral arteriovenous (sagittal sinus) O2 content difference (Ca-ssO2) and venous(sagittal sinus) PO2(PssO2) were determined before cardiac arrest (CA) and 30, 60, 120, and 240 min after CA. Results: In Group NT, Ca-ssO2 was lower at 30 min ( P < 0.05) but higher at 240 min ( P < 0.01 ) after CA than that before CA. In Group HT, Ca-ssO2 was not significantly different from that in Group NT before CA but was lower than that in Group NT at 30 min after CA ( P < 0.01 ). Ca-ssO2 was not significantly different in Group NT and HT thereafter. In both groups,PssO2 was both higher at 30 min after reperfnsion ( P < 0.01 ) and at 240 min after reperfnsion lower ( P < 0.05) than those before CA .At 30 min after reperfusion, PssO2 was higher (P<0.01) in Group HT than that in Group NT, with insignificant difference between two groups. Conclusion: Cerebral O2 delivery and uptake are mismatched after CA and resuscitation. Hypertensive reperfusion improves oxygen delivery to the brain early after CA.

  7. Hyperbaric oxygen in the treatment of hypertension- induced cerebral hemorrhage on 34 cases%高血压脑出血术后高压氧治疗34例

    Institute of Scientific and Technical Information of China (English)

    程晋成; 沈月萍; 王水平; 吴杨

    2003-01-01

    @@ INTRODUCTION In this study,we investigated effect of hyperbaric oxygen(HBO) on the hypertension- induced basio- cerebral hemorrhage.The affected patients often showed signs of cerebral circulation disorder,spasm of vessels,insufficiency of cerebral blood supply and intracranial hypertension.

  8. Puerarin protects brain tissue against cerebral ischemia/reperfusion injur y by inhibiting the inlfammator y response

    Institute of Scientific and Technical Information of China (English)

    Feng Zhou; Liang Wang; Panpan Liu; Weiwei Hu; Xiangdong Zhu; Hong Shen; Yuanyuan Yao

    2014-01-01

    Puerarin, a traditional Chinese medicine, exerts a powerful neuroprotective effect in cerebral isch-emia/reperfusion injury, but its mechanism is unknown. Here, we established rat models of middle cerebral artery ischemia/reperfusion injury using the suture method. Puerarin (100 mg/kg) was administered intraperitoneally 30 minutes before middle cerebral artery occlusion and 8 hours after reperfusion. Twenty-four hours after reperfusion, we found that puerarin signiifcantly im-proved neurological deifcit, reduced infarct size and brain water content, and notably diminished the expression of Toll-like receptor-4, myeloid differentiation factor 88, nuclear factor kappa B and tumor necrosis factor-αin the ischemic region. These data indicate that puerarin exerts an anti-inlfammatory protective effect on brain tissue with ischemia/reperfusion damage by down-regulating the expression of multiple inlfammatory factors.

  9. Effects of Acute Bleeding Followed by Hydroxyethyl Starch 130/0.4 or a Crystalloid on Propofol Concentrations, Cerebral Oxygenation, and Electroencephalographic and Haemodynamic Variables in Pigs

    Directory of Open Access Journals (Sweden)

    Aura Silva

    2014-01-01

    Full Text Available Bleeding changes the haemodynamics, compromising organ perfusion. In this study, the effects of bleeding followed by replacement with hydroxyethyl starch 130/0.4 (HES or lactated Ringer’s (LR on cerebral oxygenation and electroencephalogram-derived parameters were investigated. Twelve young pigs under propofol-remifentanil anaesthesia were bled 30 mL/kg and, after a 20-minute waiting period, volume replacement was performed with HES (GHES; N=6 or LR (GRL; N=6. Bleeding caused a decrease of more than 50% in mean arterial pressure (P<0.01 and a decrease in cerebral oximetry (P=0.039, bispectral index, and electroencephalogram total power (P=0.04 and P<0.01, resp., while propofol plasma concentrations increased (P<0.01. Both solutions restored the haemodynamics and cerebral oxygenation similarly and were accompanied by an increase in electroencephalogram total power. No differences between groups were found. However, one hour after the end of the volume replacement, the cardiac output (P=0.03 and the cerebral oxygenation (P=0.008 decreased in the GLR and were significantly lower than in GHES (P=0.02. Volume replacement with HES 130/0.4 was capable of maintaining the cardiac output and cerebral oxygenation during a longer period than LR and caused a decrease in the propofol plasma concentrations.

  10. Effects of Acute Bleeding Followed by Hydroxyethyl Starch 130/0.4 or a Crystalloid on Propofol Concentrations, Cerebral Oxygenation, and Electroencephalographic and Haemodynamic Variables in Pigs

    Science.gov (United States)

    Venâncio, Carlos; Souza, Almir P.; Ferreira, Luísa Maria; Branco, Paula Sério; de Pinho, Paula Guedes; Amorim, Pedro; Ferreira, David A.

    2014-01-01

    Bleeding changes the haemodynamics, compromising organ perfusion. In this study, the effects of bleeding followed by replacement with hydroxyethyl starch 130/0.4 (HES) or lactated Ringer's (LR) on cerebral oxygenation and electroencephalogram-derived parameters were investigated. Twelve young pigs under propofol-remifentanil anaesthesia were bled 30 mL/kg and, after a 20-minute waiting period, volume replacement was performed with HES (GHES; N = 6) or LR (GRL; N = 6). Bleeding caused a decrease of more than 50% in mean arterial pressure (P < 0.01) and a decrease in cerebral oximetry (P = 0.039), bispectral index, and electroencephalogram total power (P = 0.04 and P < 0.01, resp.), while propofol plasma concentrations increased (P < 0.01). Both solutions restored the haemodynamics and cerebral oxygenation similarly and were accompanied by an increase in electroencephalogram total power. No differences between groups were found. However, one hour after the end of the volume replacement, the cardiac output (P = 0.03) and the cerebral oxygenation (P = 0.008) decreased in the GLR and were significantly lower than in GHES (P = 0.02). Volume replacement with HES 130/0.4 was capable of maintaining the cardiac output and cerebral oxygenation during a longer period than LR and caused a decrease in the propofol plasma concentrations. PMID:24971192

  11. Molecular and histological changes in cerebral cortex and lung tissues under the effect of tramadol treatment.

    Science.gov (United States)

    Awadalla, Eatemad A; Salah-Eldin, Alaa-Eldin

    2016-08-01

    Tramadol abuse is one of the most frequent health problems in Egypt and worldwide. In most cases, tramadol abused by men face a problem with premature ejaculation. Tramadol like other opioids induces a decrease in plasma antioxidant levels, which may reflect a failure of the antioxidant defense mechanism against oxidative damage. The present work aimed to study the possible deleterious effects of oral administration of tramadol on brain and lung tissues in rats. Twenty adult male albino rats were divided into two groups; a control administered with normal saline and tramadol-treated (40mg/kg b.w.) group for 20 successive days. At the end of experimental period, blood was collected and specimens from brains and lungs were taken for histopathological and molecular studies. Malondialdehyde (MDA), reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) activities were measured in serum of control and tramadol-treated groups. Brain and lung specimens were histopathological evaluated using light microscopy. The expression levels of apoptotic related genes; Bcl-2, Bax and Caspase-3 were study in brain and lung tissues using RT-PCR analysis. We recorded a significant increase MDA level, while antioxidant enzymes; GSH, SOD and CAT were significantly decreased after tramadol-treatment. The obtained results revealed that tramadol induced a remarkable histomorphological changes in rats' brains (cerebral cortex and hippocampus) and severe histopathological changes in rats' lung when compared to that of control. On molecular level, the expression of the pro-apoptotic Bax and Caspase-3 showed a significant increase whereas the anti-apoptotic Bcl-2 decreased markedly indicating that tramadol is harmful at cellular level and can induce apoptotic changes in brain tissues. Our data confirmed the risk of increased oxidative stress, neuronal and pulmonary damage due to tramadol abuse. Although tramadol is reported to be effective in pain management, its toxicity should

  12. Near-infrared spectroscopy determined cerebral oxygenation with eliminated skin blood flow in young males

    DEFF Research Database (Denmark)

    Hirasawa, Ai; Kaneko, Takahito; Tanaka, Naoki;

    2016-01-01

    was applied to the temporal artery, estimated O2Hb was not affected by elimination of SkBF during handgrip exercise (P = 0.666) or the cognitive task (P = 0.105). These findings suggest that the algorithm with the individual correction factor allows for evaluation of changes in an accurate cerebral...

  13. Brain Tissue Oxygen: In Vivo Monitoring with Carbon Paste Electrodes

    Directory of Open Access Journals (Sweden)

    John P. Lowry

    2005-11-01

    Full Text Available In this communication we review selected experiments involving the use ofcarbon paste electrodes (CPEs to monitor and measure brain tissue O2 levels in awakefreely-moving animals. Simultaneous measurements of rCBF were performed using the H2clearance technique. Voltammetric techniques used include both differential pulse (O2 andconstant potential amperometry (rCBF. Mild hypoxia and hyperoxia produced rapidchanges (decrease and increase respectively in the in vivo O2 signal. Neuronal activation(tail pinch and stimulated grooming produced similar increases in both O2 and rCBFindicating that CPE O2 currents provide an index of increases in rCBF when such increasesexceed O2 utilization. Saline injection produced a transient increase in the O2 signal whilechloral hydrate produced slower more long-lasting changes that accompanied the behavioralchanges associated with anaesthesia. Acetazolamide increased O2 levels through an increasein rCBF.

  14. Elevated global cerebral blood flow, oxygen extraction fraction and unchanged metabolic rate of oxygen in young adults with end-stage renal disease: an MRI study

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Gang; Lou, Yaxian; Pan, Zhiying; Liu, Ya [Medical School of Nanjing University, Department of Medical Imaging, Jinling Hospital, Nanjing, Jiangsu (China); Nanjing University of Aeronautics and Astronautics, College of Aivil Aviation, Nanjing, Jiangsu (China); Wen, Jiqiu; Li, Xue; Zhang, Zhe [Medical School of Nanjing University, National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing, Jiangsu (China); Lu, Hanzhang [University of Texas Southwestern Medical Center, Advanced Imaging Research Center, Dallas, TX (United States); Liu, Wei [Siemens Shenzhen Magnetic Resonance Ltd., Shenzhen, Guangdong (China); Liu, Hui [Siemens MR NEA Collaboration, Siemens Ltd., Shanghai (China); Chen, Huijuan; Kong, Xiang; Luo, Song; Jiang, Xiaolu; Zhang, Zongjun; Zhang, Long Jiang; Lu, Guang Ming [Medical School of Nanjing University, Department of Medical Imaging, Jinling Hospital, Nanjing, Jiangsu (China)

    2016-06-15

    To noninvasively assess global cerebral blood flow (CBF), oxygen extraction fraction (OEF) and cerebral metabolic rate of oxygen (CMRO{sub 2}) in young adults with end-stage renal disease (ESRD). Thirty-six patients and 38 healthy volunteers were included and took part in MR examinations, blood and neuropsychological tests. CBF and OEF were measured by phase-contrast and T2-relaxation-under-spin-tagging MRI techniques, respectively. CMRO{sub 2} was computed from CBF, OEF and hematocrit according to Fick's principle. Correlations were performed between MR measurements, blood biochemistry measurements and neuropsychological test scores. Compared with controls, ESRD patients had elevated CBF (72.9 ± 12.5 vs. 63.8 ± 8.5 ml min{sup -1} 100 g{sup -1}, P < 0.001), elevated OEF (47.2 ± 10.2 vs. 35.8 ± 5.4 %, P < 0.001), but unaffected CMRO{sub 2} (199.5 ± 36.4 vs. 193.8 ± 28.6 μmol O{sub 2} min{sup -1} 100 g{sup -1}, P = 0.879). Hematocrit negatively correlated with CBF (r = -0.640, P < 0.001) and OEF (r = -0.701, P < 0.001), but not with CMRO{sub 2}. Altered neuropsychological test scores of ESRD patients were associated with OEF and CBF, but not with CMRO{sub 2}. There were weak relationships between eGFR and hematocrit (r = 0.308, P = 0.068) or CBF (r = 0.318, P = 0.059). Our findings suggested that anaemic young adults with ESRD may afford higher CBF and OEF to maintain a normal CMRO{sub 2}. Despite this compensatory process, however, cognitive function was still impaired and its severity was correlated with their CBF and OEF abnormality. (orig.)

  15. Dynamics of cerebral tissue injury and perfusion after temporary hypoxia-ischemia in the rat - Evidence for region-specific sensitivity and delayed damage

    NARCIS (Netherlands)

    Dijkhuizen, RM; Knollema, S; van der Worp, H. Bart; Ter Horst, GJ; De Wildt, DJ; van der Sprenkel, JWB; Tulleken, KAF; Nicolay, K

    1998-01-01

    Background and Purpose-Selective regional sensitivity and delayed damage in cerebral ischemia provide opportunities for directed and late therapy for stroke. Our aim was to characterize the spatial and temporal profile of ischemia-induced changes in cerebral perfusion and tissue status, with the use

  16. Tissue at risk in the deep middle cerebral artery territory is critical to stroke outcome

    Energy Technology Data Exchange (ETDEWEB)

    Rosso, Charlotte; Samson, Yves [Pitie-Salpetriere Hospital, AP-HP, Urgences Cerebro-Vasculaires, Paris (France); UPMC, Univ Paris 06, Paris (France); Centre de Recherche de l' Institut du Cerveau et de la Moelle epiniere, ICM, UPMC Paris 6, Inserm, U975, CNRS, UMR 7225, COGIMAGE, Paris (France); Colliot, Olivier [UPMC, Univ Paris 06, Paris (France); Centre de Recherche de l' Institut du Cerveau et de la Moelle epiniere, ICM, UPMC Paris 6, Inserm, U975, CNRS, UMR 7225, COGIMAGE, Paris (France); Valabregue, Romain [UPMC, Univ Paris 06, Paris (France); Centre de Recherche de l' Institut du Cerveau et de la Moelle epiniere, ICM, UPMC Paris 6, Inserm, U975, CNRS, UMR 7225, Centre for NeuroImaging Research (CENIR), Paris (France); Crozier, Sophie [Pitie-Salpetriere Hospital, AP-HP, Urgences Cerebro-Vasculaires, Paris (France); Dormont, Didier [UPMC, Univ Paris 06, Paris (France); Centre de Recherche de l' Institut du Cerveau et de la Moelle epiniere, ICM, UPMC Paris 6, Inserm, U975, CNRS, UMR 7225, COGIMAGE, Paris (France); Pitie-Salpetriere Hospital, AP-HP, Department of Neuroradiology, Paris (France); Lehericy, Stephane [UPMC, Univ Paris 06, Paris (France); Centre de Recherche de l' Institut du Cerveau et de la Moelle epiniere, ICM, UPMC Paris 6, Inserm, U975, CNRS, UMR 7225, Centre for NeuroImaging Research (CENIR), Paris (France); Pitie-Salpetriere Hospital, AP-HP, Department of Neuroradiology, Paris (France)

    2011-10-15

    The clinical efficacy of thrombolysis in stroke patients is explained by the increased rate of recanalization, which limits infarct growth. However, the efficacy could also be explained by the protection of specific sites of the brain. Here, we investigate where is this outcome-related tissue at risk using voxel-based analysis. We included 68 acute stroke patients with middle cerebral artery (MCA) occlusion on the admission MRI performed within 6 h of symptoms onset (H6) and 16 controls. MCA recanalization was assessed using the magnetic resonance angiography performed at day 1 (D1). Apparent diffusion coefficient (ADC) changes were analyzed using a voxel-based method between patients vs. controls group at admission (H6) in non-recanalized vs. recanalized and in 3-month poor vs. good outcome patients at D1. Complete or partial MCA recanalization was observed in 52 of 68 patients. Good outcome at 3 months occurred in 40 patients (59%). In non-recanalized patients, ADC was decreased in the deep MCA and watershed arterial territory (the lenticular nucleus, internal capsule, and the overlying periventricular white matter). This decrease was not observed in recanalized patients at D1 or patients at H6. Fiber tracking suggested that the area is crossed by the cortico-spinal, cerebellar, and intra-hemispheric association tracts. Finally, this area almost co-localized with the area associated with poor outcome. A clinically relevant area of tissue at risk may occur in patients with MCA infarcts at the level of deep white matter fiber tracts. These findings suggest that neuroprotection research should be refocused on white matter. (orig.)

  17. Eigenspectra optoacoustic tomography achieves quantitative blood oxygenation imaging deep in tissues

    Science.gov (United States)

    Tzoumas, Stratis; Nunes, Antonio; Olefir, Ivan; Stangl, Stefan; Symvoulidis, Panagiotis; Glasl, Sarah; Bayer, Christine; Multhoff, Gabriele; Ntziachristos, Vasilis

    2016-06-01

    Light propagating in tissue attains a spectrum that varies with location due to wavelength-dependent fluence attenuation, an effect that causes spectral corruption. Spectral corruption has limited the quantification accuracy of optical and optoacoustic spectroscopic methods, and impeded the goal of imaging blood oxygen saturation (sO2) deep in tissues; a critical goal for the assessment of oxygenation in physiological processes and disease. Here we describe light fluence in the spectral domain and introduce eigenspectra multispectral optoacoustic tomography (eMSOT) to account for wavelength-dependent light attenuation, and estimate blood sO2 within deep tissue. We validate eMSOT in simulations, phantoms and animal measurements and spatially resolve sO2 in muscle and tumours, validating our measurements with histology data. eMSOT shows substantial sO2 accuracy enhancement over previous optoacoustic methods, potentially serving as a valuable tool for imaging tissue pathophysiology.

  18. Eigenspectra optoacoustic tomography achieves quantitative blood oxygenation imaging deep in tissues

    Science.gov (United States)

    Tzoumas, Stratis; Nunes, Antonio; Olefir, Ivan; Stangl, Stefan; Symvoulidis, Panagiotis; Glasl, Sarah; Bayer, Christine; Multhoff, Gabriele; Ntziachristos, Vasilis

    2016-01-01

    Light propagating in tissue attains a spectrum that varies with location due to wavelength-dependent fluence attenuation, an effect that causes spectral corruption. Spectral corruption has limited the quantification accuracy of optical and optoacoustic spectroscopic methods, and impeded the goal of imaging blood oxygen saturation (sO2) deep in tissues; a critical goal for the assessment of oxygenation in physiological processes and disease. Here we describe light fluence in the spectral domain and introduce eigenspectra multispectral optoacoustic tomography (eMSOT) to account for wavelength-dependent light attenuation, and estimate blood sO2 within deep tissue. We validate eMSOT in simulations, phantoms and animal measurements and spatially resolve sO2 in muscle and tumours, validating our measurements with histology data. eMSOT shows substantial sO2 accuracy enhancement over previous optoacoustic methods, potentially serving as a valuable tool for imaging tissue pathophysiology. PMID:27358000

  19. Cerebral cortical tissue damage after hemorrhagic hypotension in near-term born lambs.

    NARCIS (Netherlands)

    Os, S.H.G. van; Tweel, E. van den; Egberts, H.; Hopman, J.; Ruitenbeek, W.; Bel, F. van; Groenendaal, F.; Bor, M. van de

    2006-01-01

    Hypotension reduces cerebral O(2) supply, which may result in brain cell damage and loss of brain cell function in the near-term neonate. The aim is to elucidate 1) to what extent the functional disturbance of the cerebral cortex, as measured with electrocortical brain activity (ECBA), is related to

  20. Peritumoral Tissue Compression is Predictive of Exudate Flux in a Rat Model of Cerebral Tumor: an MRI Study in an Embedded Tumor

    OpenAIRE

    Ewing, James R; Nagaraja, Tavarekere N.; Aryal, Madhava P.; Keenan, Kelly A.; Elmghirbi, Rasha; Bagher-Ebadian, Hassan; Panda, Swayamprava; Lu, Mei; Mikkelsen, Tom; Cabral, Glauber; Brown, Stephen L.

    2015-01-01

    MRI estimates of extracellular volume and tumor exudate flux in peritumoral tissue are demonstrated in an experimental model of cerebral tumor. Peritumoral extracellular volume predicted the tumor exudate flux.

  1. Effects of various anesthetic techniques and PaCO2 levels on cerebral oxygen balance in neurosurgical patients

    Institute of Scientific and Technical Information of China (English)

    陈绍洋; 王强; 熊利泽; 胡胜; 曾祥龙

    2003-01-01

    Objective: To assess the effects of various anesthetic techniques and PaCO2 levels on cerebral oxygen supply/consumption balance during craniotomy for removal of tumors, and to explore an anesthetic technique for neurosurgery and an appropriate degree of PaCO2 during neuroanesthesia. Methods: One hundred and fourteen patients with supratentorial tumors for elective craniotomy, ASA grade Ⅰ-Ⅱ, were randomly allocated to six groups. Patients were anesthetized with continuous intravenous infusion of 2% procaine 1.0 mg*kg-1*min-1 in Group Ⅰ, inhalation of 1.0%-1.5% isoflurane in Group Ⅱ, and infusion of 2% procaine 0.5 mg*kg-1*min-1 combined with inhalation of 0.5%-0.7% isoflurane in Group Ⅲ during the period of study. The end-tidal pressure of CO2 (PET CO2 )was maintained at 4.0 kPa in these 3 groups. In Group Ⅳ, Ⅴ and Ⅵ, the anesthetic technique was the same as that in Group Ⅰ but the PETCO2 was adjusted to 3.5, 4.0 and 4.5 kPa respectively for 60 min during which the study was performed. The radial arterial and retrograde jugular venous blood samples were obtained at the onset and the end of this study for determining jugular venous bulb oxygen saturation (SjvO2), arteriovenous oxygen content difference (AVDO2) and cerebral extraction of oxygen (CEO2). Results: In Group Ⅰ and Ⅲ SjvO2, AVDO2 and CEO2 remained stable. Although SjvO2 kept constant, AVDO2 and CEO2 decreased significantly (P<0.05) in Group Ⅱ. Moreover, AVDO2 and CEO2 in Group Ⅱ were significantly lower than those of Group Ⅲ (P<0.05). In Group Ⅳ, 60 min after hyperventilation, SjvO2 and jugular venous oxygen content(CjvO2) decreased markedly (P<0.01) while CEO2 increased significantly (P<0.01). In addition, SjvO2, CjvO2 and CEO2 in Group Ⅳ were significantly different from the corresponding parameters in Group Ⅴ and Group Ⅵ (P<0.05). In view of sustained excessive hyperventilation, SjvO2 was less than 50% in 37.5% patients of Group Ⅳ. Conclusion: Anesthesia with

  2. Changes in cerebral haemodynamics, regional oxygen saturation and amplitude-integrated continuous EEG during hypoxia-ischaemia and reperfusion in newborn piglets

    NARCIS (Netherlands)

    Ioroi, T; Peeters-Scholte, C; Post, [No Value; Groenendaal, F; van Bel, F

    2002-01-01

    Perinatal asphyxia models are necessary to obtain knowledge of the pathophysiology of hypoxia-ischaemia (HI) and to test potential neuroprotective strategies. The present study was performed in newborn piglets to obtain information about simultaneous changes in cerebral oxygenation and haemodynamics

  3. In vivo imaging of hemodynamics and oxygen metabolism in acute focal cerebral ischemic rats with laser speckle imaging and functional photoacoustic microscopy

    Science.gov (United States)

    Deng, Zilin; Wang, Zhen; Yang, Xiaoquan; Luo, Qingming; Gong, Hui

    2012-08-01

    Stroke is a devastating disease. The changes in cerebral hemodynamics and oxygen metabolism associated with stroke play an important role in pathophysiology study. But the changes were difficult to describe with a single imaging modality. Here the changes in cerebral blood flow (CBF), cerebral blood volume (CBV), and oxygen saturation (SO2) were yielded with laser speckle imaging (LSI) and photoacoustic microscopy (PAM) during and after 3-h acute focal ischemic rats. These hemodynamic measures were further synthesized to deduce the changes in oxygen extraction fraction (OEF). The results indicate that all the hemodynamics except CBV had rapid declines within 40-min occlusion of middle cerebral artery (MCAO). CBV in arteries and veins first increased to the maximum value of 112.42±36.69% and 130.58±31.01% by 15 min MCAO; then all the hemodynamics had a persistent reduction with small fluctuations during the ischemic. When ischemia lasted for 3 h, CBF in arteries, veins decreased to 17±14.65%, 24.52±20.66%, respectively, CBV dropped to 62±18.56% and 59±18.48%. And the absolute SO2 decreased by 40.52±22.42% and 54.24±11.77%. After 180-min MCAO, the changes in hemodynamics and oxygen metabolism were also quantified. The study suggested that combining LSI and PAM provides an attractive approach for stroke detection in small animal studies.

  4. How to Get Hyperbaric Oxygen Therapy for Children with Cerebral Palsy or Brain Injury: Navigating Insurance Denials, Red Tape, and Other Challenges

    Science.gov (United States)

    Console, Richard P., Jr.

    2010-01-01

    Medical professionals who use hyperbaric oxygen therapy (HBOT) say that recent studies, as well as anecdotal evidence, indicate that this treatment significantly improves the lives of many children with cerebral palsy and other types of chronic brain injury. So why do many children with these diagnoses not have access to this treatment? Simply…

  5. Cerebral hypoperfusion detected by SPECT in patients with systemic lupus erythematosus is related to clinical activity and cumulative tissue damage.

    Science.gov (United States)

    López-Longo, F J; Carol, N; Almoguera, M I; Olazarán, J; Alonso-Farto, J C; Ortega, A; Monteagudo, I; González, C Manuel; Carreño, L

    2003-01-01

    Cerebral single-photon emission computed tomography (SPECT) is a sensitive technique for the detection of central nervous system (CNS) involvement in systemic lupus erythematosus (SLE). The objective was to determine whether a relationship exists between cerebral hypoperfusion as detected by cerebral SPECT, cumulative tissue damage and the clinical activity of SLE. Cerebral technetium-99m-L,L-ethyl cysteinate dimer (99mTc-ECD) SPECT was performed in two groups of patients: 10 women with SLE (Group A) who had no previous history of major neuropsychiatric (NPS) manifestations and no minor NPS symptoms in the last six months, and 57 unselected women with SLE (Group B). In the same week that SPECT was performed, the SLE disease activity index (SLEDAI), SLICC/ACR damage index, native anti-DNA antibodies (ELISA) and erythrocyte sedimentation rate (ESR) were determined. In Group A, cerebral SPECT showed moderate or severe hypoperfusion (abnormal SPECT) in five patients without NPS symptoms, unrelated to age (mean 24.8 versus 27.8 years) or disease duration (mean 6.8 versus 9 years). Patients with significant cerebral hypoperfusion had greater clinical disease activity (mean SLEDAI 13.6 versus 7.6) (SLEDAI > 7 in 5/5 versus 1/5; Fisher: 0.023; OR: 33; 95% CI: 2.3-469.8) and ESR (mean 43.6 versus 9.8; P < 0.05). In Group B, the mean age of the 57 unselected women with SLE was 37 years (SD 6.3) and the mean duration of the disease was 9.7 years (SD 6.3). Cerebral SPECT revealed normal perfusion or mild hypoperfusion (normal SPECT) in 30 patients (52.6%), and moderate or severe hypoperfusion in 27 (47.4%). Hypoperfusion was unrelated to age, duration of SLE or concentrations of anti-DNA antibodies and C3 and C4 fractions. Patients with significant cerebral hypoperfusion had more active clinical disease (mean SLEDAI 13.92; SD 8.44 versus 4.56; SD 4.15) (Mann-Whitney, P < 0.005), more cumulative tissue damage (mean SLICC 2.66; SD 2.84 versus 1.03; SD 1.51) (Mann-Whitney, P = 0

  6. Non-invasive monitoring of tissue oxygenation during laparoscopic donor nephrectomy

    Directory of Open Access Journals (Sweden)

    Kirk Allan D

    2008-04-01

    Full Text Available Abstract Background Standard methods for assessment of organ viability during surgery are typically limited to visual cues and tactile feedback in open surgery. However, during laparoscopic surgery, these processes are impaired. This is of particular relevance during laparoscopic renal donation, where the condition of the kidney must be optimized despite considerable manipulation. However, there is no in vivo methodology to monitor renal parenchymal oxygenation during laparoscopic surgery. Methods We have developed a method for the real time, in vivo, whole organ assessment of tissue oxygenation during laparoscopic nephrectomy to convey meaningful biological data to the surgeon during laparoscopic surgery. We apply the 3-CCD (charge coupled device camera to monitor qualitatively renal parenchymal oxygenation with potential real-time video capability. Results We have validated this methodology in a porcine model across a range of hypoxic conditions, and have then applied the method during clinical laparoscopic donor nephrectomies during clinically relevant pneumoperitoneum. 3-CCD image enhancement produces mean region of interest (ROI intensity values that can be directly correlated with blood oxygen saturation measurements (R2 > 0.96. The calculated mean ROI intensity values obtained at the beginning of the laparoscopic nephrectomy do not differ significantly from mean ROI intensity values calculated immediately before kidney removal (p > 0.05. Conclusion Here, using the 3-CCD camera, we qualitatively monitor tissue oxygenation. This means of assessing intraoperative tissue oxygenation may be a useful method to avoid unintended ischemic injury during laparoscopic surgery. Preliminary results indicate that no significant changes in renal oxygenation occur as a result of pneumoperitoneum.

  7. Endothelin receptor blockade improves oxygenation in contralateral TRAM flap tissue in pigs.

    Science.gov (United States)

    Erni, D; Wessendorf, R; Wettstein, R; Schilling, M K; Banic, A

    2001-07-01

    Partial skin and fat necrosis is the most common complication occurring in TRAM flaps. It is related to disturbances of the microcirculation and oxygenation in the contralateral part of the flap. It may be hypothesised that the development of necrosis is promoted by the vasoconstrictor endothelin, the production of which is enhanced in ischaemic flap tissues. The purpose of this study was to evaluate the effect of tezosentan, a new endothelin receptor blocker, on microcirculation and oxygenation in experimental TRAM flaps. The administration of tezosentan began preoperatively (3 mg/kg body weight) and then continued at a rate of 1.5 mg/kg/h. A TRAM flap with a skin island measuring 16 x 8 cm was raised in the middle of the epigastrium in minipigs. The flap was pedicled on the right superior epigastric vessels. Microcirculatory blood flow was measured with laser Doppler flowmetry and tissue oxygen tension was measured with a Clark-type microprobe. Dominant subcutaneous veins were cannulated in both the ipsilateral and the contralateral parts of the flap. Subdermal tissue oxygen tension in the contralateral part of the flap was significantly reduced 4h after surgery to 5 mmHg (ca. 48 mmHg in normal tissue) in the control group, but to only 12 mmHg in the group that had been administered tezosentan (Peffluent of the contralateral part of the flap, although microcirculatory blood flow remained virtually unchanged. Our findings suggest that tezosentan improves oxygenation and metabolism in the jeopardised contralateral flap tissue, probably as a result of a decrease in venous vascular resistance and fluid extravasation.

  8. The effect of Sub-maximal exercise-rehabilitation program on cardio-respiratory endurance indexes and oxygen pulse in patients with spastic cerebral palsy

    Directory of Open Access Journals (Sweden)

    M Izadi

    2006-05-01

    Full Text Available Background: Physical or cardio-respiratory fitness are of the best important physiological variables in children with cerebral palsy (CP, but the researches on exercise response of individuals with CP are limited. Our aim was to determine the effect of sub-maximal rehabilitation program (aerobic exercise on maximal oxygen uptake, oxygen pulse and cardio- respiratory physiological variables of children with moderate to severe spastic cerebral palsy diplegia and compare with able-bodied children. Methods: In a controlled clinical trial study, 15 children with diplegia spastic cerebral palsy, were recruited on a voluntarily basis (experimental group and 18 subjects without neurological impairments selected as control group. In CP group, aerobic exercise program performed on the average of exercise intensity (144 beat per minute of heart rate, 3 times a week for 3 months. The time of each exercise session was 20-25 minutes. Dependent variables were measured in before (pretest and after (post test of rehabilitation program through Mac Master Protocol on Tantories cycle ergometer in CP group and compared with the control group. Results: The oxygen pulse (VO2/HR during ergometery protocol was significantly lower in CP group than normal group (P<0.05. No significant statistical difference in maximal oxygen uptake (VO2 max was found between groups. The rehabilitation program leads to little increase of this variable in CP group. After sub-maximal exercise in pretest and post test, the heart rate of patient group was greater than control group, and aerobic exercise leads to significant decrease in heart rate in CP patients(P<0.05. Conclusion: The patients with spastic cerebral palsy, because of high muscle tone, severe spasticity and involuntarily movements have higher energy cost and lower aerobic fitness than normal people. The rehabilitation exercise program can improve physiological function of muscle and cardio-respiratory endurance in these

  9. Rate of change in cerebral oxygenation and blood pressure in response to passive changes in posture: a comparison between pure autonomic failure patients and controls.

    Science.gov (United States)

    Tachtsidis, Ilias; Elwell, Clare E; Leung, Terence S; Bleasdale-Barr, Katharine; Hunt, Katharine; Toms, Nathan; Smith, Martin; Mathias, Christopher J; Delpy, David T

    2005-01-01

    The cardiovascular and cerebrovascular responses to head-up postural change are compromised in pure autonomic failure (PAF) patients because of sympathetic denervation. The aim of this study was to characterize the rate of change of systemic mean blood pressure (MBP) and cerebral haemodynamics in response to passive posture changes. Nine PAF patients and 9 age-matched controls took part in this study. MBP and oxy- (O2Hb), deoxy-haemoglobin (HHb), and tissue oxygenation index (TOI) on the forehead were continuously monitored non-invasively using the Portapres and near-infrared spectroscopy (NIRS), respectively. From visual inspection of the haemoglobin difference signal (Hb(diff) = O2Hb-HHb), seven distinct phases were marked (1: supine, 2: start passive tilt, 3: head up to 60 degrees degrees, 4: end of tilt, 5: tilt reversal, 6: return to supine, 7: rest); the same time points were used for all of the other signals. For each phase, the slope was calculated using a linear regression algorithm. Significant differences were found between PAF patients and controls in the Hb(diff) slope magnitudes for phases 3 (P rate of change suggest differences in blood vessel resistance related to sympathetic activation.

  10. Episodes of apnea and bradycardia in the preterm newborn: impact on cerebral oxygenation measured by near-infrared spectrophotometry

    Science.gov (United States)

    Van Huffel, Sabine; Craemers, Johan; Lenaerts, Bart; Daniels, Hans; Naulaers, Gunnar; Casaer, Paul

    1998-12-01

    The objective of this study is to evaluate the effect of episodes of apneas and/or mild bradycardia (heart rate decreases of 10 to 20% or more) on cerebral oxyhemoglobin (HbO2) and reduced hemoglobin (Hb) concentration as measured by Near Infrared Spectrophotometry (NIRS). Measurements were carried out on 7 preterm infants who experienced apneic and bradycardiac events. It is shown how to characterize these events using time-frequency analysis. In addition to NIRS (performed with a NIRO-500 from Hamamatsu, Japan), the heart rate, ECG, peripheral arterial oxygen saturation (measured at the foot) and respiration (abdominal and thoracic pressure, and nasal airflow) were continuously recorded. The impact of apneic events and periodic breathing on these measurements reveals the clinical relevance of NIRS. In particular, we investigate whether these changes in heart rate and respiration also influence HbO2 and reduced Hb concentration in neonatal brain. These changes are characterized, as well as their relationships with the other simultaneously recorded signals such as peripheral arterial oxygen saturation.

  11. Comparable cerebral oxygenation patterns in younger and older adults during dual-task walking with increasing load

    Directory of Open Access Journals (Sweden)

    Sarah A. Fraser

    2016-10-01

    Full Text Available The neuroimaging literature on dual-task gait clearly demonstrates increased prefrontal cortex (PFC involvement when performing a cognitive task while walking. However, findings from direct comparisons of the cerebral oxygenation patterns of younger (YA and older (OA adults during dual-task walking are mixed and it is unclear how YA and OA respond to increasing cognitive load (difficulty while walking. This functional near infra-red (fNIRS study examined cerebral oxygenation of YA and OA during self-paced dual-task treadmill walking at two different levels of cognitive load (auditory n-back. Changes in accuracy (% as well as oxygenated (HbO and deoxygenated (HbR hemoglobin were examined. For the HbO and HbR measures, eight regions of interest (ROIs were assessed: the anterior and posterior dorsolateral and ventrolateral PFC (aDLPFC, pDLPFC, aVLPFC, pVLPFC in each hemisphere. Nineteen YA (M = 21.83 yrs and 14 OA (M = 66.85 yrs walked at a self-selected pace while performing auditory 1-back and 2-back tasks. Walking alone (single motor: SM and performing the cognitive tasks alone (single cognitive: SC were compared to dual-task walking (DT = SM + SC. In the behavioural data, participants were more accurate in the lowest level of load (1-back compared to the highest (2-back; p ˂ .001. YA were more accurate than OA overall (p = .009, and particularly in the 2-back task (p = .048. In the fNIRS data, both younger and older adults had task effects (SM < DT in specific ROIs for ∆HbO (3 YA, 1 OA and ∆HbR (7 YA, 8 OA. After controlling for walk speed differences, direct comparisons between YA and OA did not reveal significant age differences, but did reveal a difficulty effect in HbO in the left aDLPFC (p = .028 and significant task effects (SM < DT in HbR for 6 of the 8 ROIs. Findings suggest that YA and OA respond similarly to manipulations of cognitive load when walking on a treadmill at a self-selected pace.

  12. Oxygen regulation of uricase and sucrose synthase synthesis in soybean callus tissue is exerted at the mRNA level

    DEFF Research Database (Denmark)

    Xue, Z T; Larsen, K; Jochimsen, B U

    1991-01-01

    The effect of lowering oxygen concentration on the expression of nodulin genes in soybean callus tissue devoid of the microsymbiont has been examined. Poly(A)+ RNA was isolated from tissue cultivated in 4% oxygen and in normal atmosphere. Quantitative mRNA hybridization experiments using nodule...

  13. Effect of oxygen breathing and perfluorocarbon emulsion treatment on air bubbles in adipose tissue during decompression sickness

    DEFF Research Database (Denmark)

    Randsoe, T; Hyldegaard, O

    2009-01-01

    for nitrogen causing faster nitrogen tissue desaturation. In anesthetized rats decompressed from a 60-min hyperbaric exposure breathing air at 385 kPa, we visually followed the resolution of micro-air bubbles injected into abdominal adipose tissue while the rats breathed either air, oxygen, or oxygen breathing...

  14. CEREBRAL SINUS THROMBOSIS IN A CASE OF ANTI-PHOSPHOLIPID ANTIBODY SYNDROME WITHOUT ASSOCIATED CONNECTIVE TISSUE INVOLVEMENT

    Directory of Open Access Journals (Sweden)

    Biswarup

    2014-12-01

    Full Text Available : The association of antiphospholipid antibodies with vascular thrombotic episodes is well established. In absence of other connective tissue disease such an association is very rare & known as the primary antiphospholipid antibody syndrome. Cerebral venous sinus thrombosis is associated with hypercoaguable states and a number of immune-mediated conditions. However the report of cerebral venous sinus thrombosis with antiphospholipid antibodies alone is limited. Here a case presenting with painful bilateral ophthalmoplegia with bilateral optic disc edema (due to raised intra cranial tension showing positive lupus anticoagulant in serum and right central venous sinus (transverse and sigmoid thrombosis on MRI and MR venogram is reported which showed clinical improvement with anticoagulant therapy

  15. Artificial membrane-binding proteins stimulate oxygenation of stem cells during engineering of large cartilage tissue

    Science.gov (United States)

    Armstrong, James P. K.; Shakur, Rameen; Horne, Joseph P.; Dickinson, Sally C.; Armstrong, Craig T.; Lau, Katherine; Kadiwala, Juned; Lowe, Robert; Seddon, Annela; Mann, Stephen; Anderson, J. L. Ross; Perriman, Adam W.; Hollander, Anthony P.

    2015-06-01

    Restricted oxygen diffusion can result in central cell necrosis in engineered tissue, a problem that is exacerbated when engineering large tissue constructs for clinical application. Here we show that pre-treating human mesenchymal stem cells (hMSCs) with synthetic membrane-active myoglobin-polymer-surfactant complexes can provide a reservoir of oxygen capable of alleviating necrosis at the centre of hyaline cartilage. This is achieved through the development of a new cell functionalization methodology based on polymer-surfactant conjugation, which allows the delivery of functional proteins to the hMSC membrane. This new approach circumvents the need for cell surface engineering using protein chimerization or genetic transfection, and we demonstrate that the surface-modified hMSCs retain their ability to proliferate and to undergo multilineage differentiation. The functionalization technology is facile, versatile and non-disruptive, and in addition to tissue oxygenation, it should have far-reaching application in a host of tissue engineering and cell-based therapies.

  16. Tissue oxygen regime and factors guaranteeing it in vibration disease of miners

    Energy Technology Data Exchange (ETDEWEB)

    Filin, A.P.; Dudinskii, A.M.; Amanbekov, U.A.

    1985-09-01

    Trophic function of microcirculatory system during vibration disease (VD) is examined. Oxygen regime of soft tissues of upper extremities of 198 drillers with various stages of VD and 38 healthy miners as control group was studied by combined use of chronoamperography and ischemic test. Hemodynamics of microcirculatory system was studied by rheovasography and radioisotope (/sup 133/X) clearance technique. Miners with VD showed reliable decrease in the oxygen supply to soft tissues of fingers, wrist and forearms relative to clinical manifestations of VD. Symptoms increase with limitation of oxygen supply to tissues due to decrease of volume of blood flow in microcirculatory channels and metabolic activity of tissues. Method of chronoamperography and ischemic test used by the authors has broad application for diagnosis. It forms the basis of selecting optimum methods of effectively treating and controling VD such as massage (number of treatments depends on status of patient) combined with electrophoresis with sulfide of calcium chloride on cervical and thoracic portions of spine and on wrists. 2 references.

  17. Near-infrared spectroscopy assessed cerebral oxygenation during open abdominal aortic aneurysm repair

    DEFF Research Database (Denmark)

    Sørensen, H.; Nielsen, H. B.; Secher, N H

    2016-01-01

    intend to adjust ventilation according end-tidal CO2 tension (EtCO2) and here evaluated to what extent that strategy maintains frontal lobe oxygenation (ScO2) as determined by near infrared spectroscopy. For 44 patients [5 women, aged 70 (48-83) years] ScO2, mean arterial pressure (MAP), EtCO2...

  18. Increased cerebral oxygen extraction capacity in patients with Alzheimer’s disease

    DEFF Research Database (Denmark)

    Eskildsen, Simon Fristed; Gyldensted, Louise; Nagenthiraja, Kartheeban;

    Vascular risk factors are suspected to play a role in the etiology of Alzheimer’s disease. Recently, a model that relates capillary dysfunction to the development of AD was proposed [1]. The model predicts that increased capillary dysfunction leads to increased oxygen extraction in order to support...

  19. Inspired Carbon Dioxide During Hypoxia: Effects on Task Performance and Cerebral Oxygen Saturation

    NARCIS (Netherlands)

    Dorp, E. van; Los, M.; Dirven, P.; Sarton, E.; Valk, P.; Teppema, L.; Stienstra, R.; Dahan, A.

    2007-01-01

    Introduction: Exposure to a hypoxic environment has a deleterious effect on physiological and mental functions. We studied the effect of added inspired CO2 during artificially induced hypoxic normobaric hypoxia (oxygen saturation ∼80%) on complex task performance. Methods: In random order, 22 health

  20. Combined administration of hyperbaric oxygen and hydroxocobalamin improves cerebral metabolism after acute cyanide poisoning in rats

    DEFF Research Database (Denmark)

    Hansen, M B; Olsen, Niels Vidiendal; Hyldegaard, O

    2013-01-01

    Hyperbaric oxygen therapy (HBOT) or intravenous hydroxocobalamin (OHCob) both abolish cyanide (CN)-induced surges in interstitial brain lactate and glucose concentrations. HBOT has been shown to induce a delayed increase in whole blood CN concentrations, whereas OHCob may act as an intravascular CN...

  1. [Effect of hyperbaric oxygenation on local tissue blood flow to a small intestine transplant intended for esophagoplasty].

    Science.gov (United States)

    Vinnitskiĭ, L I; Piuskiulian, L I; Zhidkov, I L; Demurov, E A

    1981-04-01

    The time course of the local tissue blood flow in the small intestinal graft used for esophagoplasty was studied in 54 acute experiments on rabbits exposed to hyperbaric oxygenation (1 hour, 2 ata). It has been shown that hyperbaric oxygenation prevents alterations in the local tissue blood flow in the small intestine. This fact provides evidence in favour of hyperbaric oxygenation application under clinical conditions.

  2. A novel method of combining blood oxygenation and blood flow sensitive magnetic resonance imaging techniques to measure the cerebral blood flow and oxygen metabolism responses to an unknown neural stimulus.

    Directory of Open Access Journals (Sweden)

    Aaron B Simon

    Full Text Available Simultaneous implementation of magnetic resonance imaging methods for Arterial Spin Labeling (ASL and Blood Oxygenation Level Dependent (BOLD imaging makes it possible to quantitatively measure the changes in cerebral blood flow (CBF and cerebral oxygen metabolism (CMRO(2 that occur in response to neural stimuli. To date, however, the range of neural stimuli amenable to quantitative analysis is limited to those that may be presented in a simple block or event related design such that measurements may be repeated and averaged to improve precision. Here we examined the feasibility of using the relationship between cerebral blood flow and the BOLD signal to improve dynamic estimates of blood flow fluctuations as well as to estimate metabolic-hemodynamic coupling under conditions where a stimulus pattern is unknown. We found that by combining the information contained in simultaneously acquired BOLD and ASL signals through a method we term BOLD Constrained Perfusion (BCP estimation, we could significantly improve the precision of our estimates of the hemodynamic response to a visual stimulus and, under the conditions of a calibrated BOLD experiment, accurately determine the ratio of the oxygen metabolic response to the hemodynamic response. Importantly we were able to accomplish this without utilizing a priori knowledge of the temporal nature of the neural stimulus, suggesting that BOLD Constrained Perfusion estimation may make it feasible to quantitatively study the cerebral metabolic and hemodynamic responses to more natural stimuli that cannot be easily repeated or averaged.

  3. A novel method of combining blood oxygenation and blood flow sensitive magnetic resonance imaging techniques to measure the cerebral blood flow and oxygen metabolism responses to an unknown neural stimulus.

    Science.gov (United States)

    Simon, Aaron B; Griffeth, Valerie E M; Wong, Eric C; Buxton, Richard B

    2013-01-01

    Simultaneous implementation of magnetic resonance imaging methods for Arterial Spin Labeling (ASL) and Blood Oxygenation Level Dependent (BOLD) imaging makes it possible to quantitatively measure the changes in cerebral blood flow (CBF) and cerebral oxygen metabolism (CMRO(2)) that occur in response to neural stimuli. To date, however, the range of neural stimuli amenable to quantitative analysis is limited to those that may be presented in a simple block or event related design such that measurements may be repeated and averaged to improve precision. Here we examined the feasibility of using the relationship between cerebral blood flow and the BOLD signal to improve dynamic estimates of blood flow fluctuations as well as to estimate metabolic-hemodynamic coupling under conditions where a stimulus pattern is unknown. We found that by combining the information contained in simultaneously acquired BOLD and ASL signals through a method we term BOLD Constrained Perfusion (BCP) estimation, we could significantly improve the precision of our estimates of the hemodynamic response to a visual stimulus and, under the conditions of a calibrated BOLD experiment, accurately determine the ratio of the oxygen metabolic response to the hemodynamic response. Importantly we were able to accomplish this without utilizing a priori knowledge of the temporal nature of the neural stimulus, suggesting that BOLD Constrained Perfusion estimation may make it feasible to quantitatively study the cerebral metabolic and hemodynamic responses to more natural stimuli that cannot be easily repeated or averaged.

  4. Tissue oxygen monitoring by photoacoustic lifetime imaging (PALI) and its application to image-guided photodynamic therapy (PDT)

    Science.gov (United States)

    Shao, Qi; Morgounova, Ekaterina; Ashkenazi, Shai

    2015-03-01

    The oxygen partial pressure (pO2), which results from the balance between oxygen delivery and its consumption, is a key component of the physiological state of a tissue. Images of oxygen distribution can provide essential information for identifying hypoxic tissue and optimizing cancer treatment. Previously, we have reported a noninvasive in vivo imaging modality based on photoacoustic lifetime. The technique maps the excited triplet state of oxygen-sensitive dye, thus reflects the spatial and temporal distribution of tissue oxygen. We have applied PALI on tumor on small animals to identify hypoxia area. We also showed that PALI is able monitor changes of tissue oxygen, in an acute ischemia and breathing modulation model. Here we present our work on developing a treatment/imaging modality (PDT-PALI) that integrates PDT and a combined ultrasound/photoacoustic imaging system. The system provides real-time feedback of three essential parameters namely: tissue oxygen, light penetration in tumor location, and distribution of photosensitizer. Tissue oxygen imaging is performed by applying PALI, which relies on photoacoustic probing of oxygen-dependent, excitation lifetime of Methylene Blue (MB) photosensitizer. Lifetime information can also be used to generate image showing the distribution of photosensitizer. The level and penetration depth of PDT illumination can be deduced from photoacoustic imaging at the same wavelength. All images will be combined with ultrasound B-mode images for anatomical reference.

  5. The dual roles of red blood cells in tissue oxygen delivery

    DEFF Research Database (Denmark)

    Jensen, Frank Bo

    2009-01-01

    Vertebrate red blood cells (RBCs) seem to serve tissue oxygen delivery in two distinct ways. Firstly, RBCs enable the adequate transport of O2 between respiratory surfaces and metabolizing tissues by means of their high intracellular concentration of hemoglobin (Hb), appropriate allosteric...... that enhance blood flow in hypoxic tissues. This latter function could be important in matching tissue O2 delivery with local O2 demand. Three main mechanisms by which RBCs can regulate their own distribution in the microcirculation have been proposed. These are: (1) deoxygenation-dependent release of ATP from...... with regard to their mechanisms, experimental evidence in their support and details that remain unresolved. The prime focus is on human/mammalian models, where most evidence for a role of erythrocyte ATP and NO release in blood flow regulation have accumulated. Information from other vertebrate groups...

  6. Localized increase of tissue oxygen tension by magnetic targeted drug delivery

    Science.gov (United States)

    Liong, Celine; Ortiz, Daniel; Ao-ieong, Eilleen; Navati, Mahantesh S.; Friedman, Joel M.; Cabrales, Pedro

    2014-07-01

    Hypoxia is the major hindrance to successful radiation therapy of tumors. Attempts to increase the oxygen (O2) tension (PO2) of tissue by delivering more O2 have been clinically disappointing, largely due to the way O2 is transported and released by the hemoglobin (Hb) within the red blood cells (RBCs). Systemic manipulation of O2 transport increases vascular resistance due to metabolic autoregulation of blood flow to prevent over oxygenation. This study investigates a new technology to increase O2 delivery to a target tissue by decreasing the Hb-O2 affinity of the blood circulating within the targeted tissue. As the Hb-O2 affinity decreases, the tissue PO2 to satisfy tissue O2 metabolic needs increases without increasing O2 delivery or extraction. Paramagnetic nanoparticles (PMNPs), synthetized using gadolinium oxide, were coated with the cell permeable Hb allosteric effector L35 (3,5-trichlorophenylureido-phenoxy-methylpropionic acid). L35 decreases Hb affinity for O2 and favors the release of O2. The L35-coated PMNPs (L35-PMNPs) were intravenously infused (10 mg kg-1) to hamsters instrumented with the dorsal window chamber model. A magnetic field of 3 mT was applied to localize the effects of the L35-PMNPs to the window chamber. Systemic O2 transport characteristics and microvascular tissue oxygenation were measured after administration of L35-PMNPs with and without magnetic field. The tissue PO2 in untreated control animals was 25.2 mmHg. L35-PMNPs without magnetic field decreased tissue PO2 to 23.4 mmHg, increased blood pressure, and reduced blood flow, largely due to systemic modification of Hb-O2 affinity. L35-PMNPs with magnetic field increased tissue PO2 to 27.9 mmHg, without systemic or microhemodynamic changes. These results indicate that localized modification of Hb-O2 affinity can increase PO2 of target tissue without affecting systemic O2 delivery or triggering O2 autoregulation mechanisms. This technology can be used to treat local hypoxia and to

  7. Measurement of characteristic prompt gamma rays emitted from oxygen and carbon in tissue-equivalent samples during proton beam irradiation

    OpenAIRE

    Polf, Jerimy C.; Panthi, Rajesh; Mackin, Dennis S; McCleskey, Matt; Saastamoinen, Antti; Roeder, Brian T; Beddar, Sam

    2013-01-01

    The purpose of this work was to characterize how prompt gamma (PG) emission from tissue changes as a function of carbon and oxygen concentration, and to assess the feasibility of determining elemental concentration in tissues irradiated with proton beams. For this study, four tissue-equivalent water-sucrose samples with differing densities and concentrations of carbon, hydrogen, and oxygen were irradiated with a 48 MeV proton pencil beam. The PG spectrum emitted from each sample was measured ...

  8. Tissue plasminogen activator and plasminogen activator inhibitor 1 contribute to sonic hedgehog-induced in vitro cerebral angiogenesis.

    Directory of Open Access Journals (Sweden)

    Hua Teng

    Full Text Available The molecular mechanisms underlying cerebral angiogenesis have not been fully investigated. Using primary mouse brain endothelial cells (MBECs and a capillary-like tube formation assay, we investigated whether the sonic hedgehog (Shh signaling pathway is coupled with the plasminogen/plasmin system in mediating cerebral angiogenesis. We found that incubation of MBECs with recombinant human Shh (rhShh substantially increased the tube formation in naïve MBECs. This was associated with increases in tissue plasminogen activator (tPA activation and reduction of plasminogen activator inhibitor 1 (PAI-1. Blockage of the Shh pathway with cyclopamine abolished the induction of tube formation and the effect of rhShh on tPA and PAI-1. Addition of PAI-1 reduced rhShh-augmented tube formation. Genetic ablation of tPA in MBECs impaired tube formation and downregulated of vascular endothelial growth factor (VEGF and angiopoietin 1 (Ang1. Addition of rhShh to tPA-/- MBECs only partially restored the tube formation and upregulated Ang1, but not VEGF, although rhShh increased VEGF and Ang1 expression on wild-type MBECs. Complete restoration of tube formation in tPA-/- MBECs was observed only when both exogenous Shh and tPA were added. The present study provides evidence that tPA and PAI-1 contribute to Shh-induced in vitro cerebral angiogenesis.

  9. Post-hypoxic and ischemic neuroprotection of BMP-7 in the cerebral cortex and caudate-putamen tissue of rat.

    Science.gov (United States)

    Luan, Liju; Yang, Xiaomei; Zhou, Changman; Wang, Ke; Qin, Lihua

    2015-03-01

    Previous reports have indicated that exogenous bone morphogenetic protein-7 (BMP-7) has a neuroprotective effect after cerebral ischemia injury and promotes motor function recovery, but the appropriate BMP-7 concentration and time course are unclear. Here, we assessed endogenous BMP-7 expression in hypoxia and ischemia-damaged brain tissues and investigated the effects of different BMP-7 concentrations in pre- and post-hypoxic primary rat neurons. The results showed that BMP-7 expression was significantly higher in the ischemic hemisphere. The expressions of BMP-7 and caspase-3 were localized in the cytoplasm of the primary cerebral cortical and caudate-putamen neurons 24h after hypoxia/reoxygenation. After BMP-7 treatment, the number of caspase-3 positive neurons began to decrease with increasing BMP-7 concentrations up to 80ng/ml, but not beyond. Although the numbers of caspase-3-positive neurons between pre- and post-hypoxia/reoxygenation were not significantly different, more dendrites were observed in the groups treated prior to hypoxia/reoxygenation. These results suggest that increased BMP-7 expression can be induced in the cerebral cortex and caudate-putamen both in vivo and in vitro in hypoxic-ischemic states. The neuroprotective mechanism of BMP-7 may include apoptosis suppression, and its effect was enhanced from 40 to 80ng/ml. Pre-hypoxic BMP-7 treatment may be useful to stimulate dendrite sprouting in non-injured neurons.

  10. Carbogen inhalation increases oxygen transport to hypoperfused brain tissue in patients with occlusive carotid artery disease Increased oxygen transport to hypoperfused brain

    DEFF Research Database (Denmark)

    Ashkanian, Mahmoud; Gjedde, Albert; Mouridsen, Kim

    2009-01-01

    comparisons by an additive ANOVA model showed that carbogen significantly increased CBF by 7.51 + or - 1.62 ml/100 g/min while oxygen tended to reduce it by -3.22 + or - 1.62 ml/100 g/min. A separate analysis of the hemisphere contralateral to the hypoperfused hemisphere showed that carbogen significantly...... and Sa(O2) are readily obtained with carbogen, while oxygen increases only Sa(O2). Thus, carbogen improves oxygen transport to brain tissue more efficiently than oxygen alone. Further studies with more subjects are, however, needed to investigate the applicability of carbogen for long-term inhalation...

  11. Erythropoietin reduces apoptosis of brain tissue cells in rats after cerebral ischemia/reperfusion injury: a characteristic analysis using magnetic resonance imaging

    Directory of Open Access Journals (Sweden)

    Chun-juan Jiang

    2016-01-01

    Full Text Available Some in vitro experiments have shown that erythropoietin (EPO increases resistance to apoptosis and facilitates neuronal survival following cerebral ischemia. However, results from in vivo studies are rarely reported. Perfusion-weighted imaging (PWI and diffusion-weighted imaging (DWI have been applied successfully to distinguish acute cerebral ischemic necrosis and penumbra in living animals; therefore, we hypothesized that PWI and DWI could be used to provide imaging evidence in vivo for the conclusion that EPO could reduce apoptosis in brain areas injured by cerebral ischemia/reperfusion. To validate this hypothesis, we established a rat model of focal cerebral ischemia/reperfusion injury, and treated with intra-cerebroventricular injection of EPO (5,000 U/kg 20 minutes before injury. Brain tissue in the ischemic injury zone was sampled using MRI-guided localization. The relative area of abnormal tissue, changes in PWI and DWI in the ischemic injury zone, and the number of apoptotic cells based on TdT-mediated dUTP-biotin nick end-labeling (TUNEL were assessed. Our findings demonstrate that EPO reduces the relative area of abnormally high signal in PWI and DWI, increases cerebral blood volume, and decreases the number of apoptotic cells positive for TUNEL in the area injured by cerebral ischemia/reperfusion. The experiment provides imaging evidence in vivo for EPO treating cerebral ischemia/reperfusion injury.

  12. Erythropoietin reduces apoptosis of brain tissue cells in rats after cerebral ischemia/reperfusion injury:a characteristic analysis using magnetic resonance imaging

    Institute of Scientific and Technical Information of China (English)

    Chun-juan Jiang; Zhong-juan Wang; Yan-jun Zhao; Zhui-yang Zhang; Jing-jing Tao; Jian-yong Ma

    2016-01-01

    Somein vitro experiments have shown that erythropoietin (EPO) increases resistance to apoptosis and facilitates neuronal survival follow-ing cerebral ischemia. However, results fromin vivo studies are rarely reported. Perfusion-weighted imaging (PWI) and diffusion-weighted imaging (DWI) have been applied successfully to distinguish acute cerebral ischemic necrosis and penumbra in living animals; therefore, we hypothesized that PWI and DWI could be used to provide imaging evidencein vivo for the conclusion that EPO could reduce apoptosis in brain areas injured by cerebral ischemia/reperfusion. To validate this hypothesis, we established a rat model of focal cerebral ischemia/reperfusion injury, and treated with intra-cerebroventricular injection of EPO (5,000 U/kg) 20 minutes before injury. Brain tissue in the ischemic injury zone was sampled using MRI-guided localization. The relative area of abnormal tissue, changes in PWI and DWI in the ischemic injury zone, and the number of apoptotic cells based on TdT-mediated dUTP-biotin nick end-labeling (TUNEL) were assessed. Our ifndings demonstrate that EPO reduces the relative area of abnormally high signal in PWI and DWI, increases cerebral blood volume, and decreases the number of apoptotic cells positive for TUNEL in the area injured by cerebral ischemia/reperfusion. The experiment pro-vides imaging evidencein vivo for EPO treating cerebral ischemia/reperfusion injury.

  13. Erythropoietin reduces apoptosis of brain tissue cells in rats after cerebral ischemia/reperfusion injury: a characteristic analysis using magnetic resonance imaging.

    Science.gov (United States)

    Jiang, Chun-Juan; Wang, Zhong-Juan; Zhao, Yan-Jun; Zhang, Zhui-Yang; Tao, Jing-Jing; Ma, Jian-Yong

    2016-09-01

    Some in vitro experiments have shown that erythropoietin (EPO) increases resistance to apoptosis and facilitates neuronal survival following cerebral ischemia. However, results from in vivo studies are rarely reported. Perfusion-weighted imaging (PWI) and diffusion-weighted imaging (DWI) have been applied successfully to distinguish acute cerebral ischemic necrosis and penumbra in living animals; therefore, we hypothesized that PWI and DWI could be used to provide imaging evidence in vivo for the conclusion that EPO could reduce apoptosis in brain areas injured by cerebral ischemia/reperfusion. To validate this hypothesis, we established a rat model of focal cerebral ischemia/reperfusion injury, and treated with intra-cerebroventricular injection of EPO (5,000 U/kg) 20 minutes before injury. Brain tissue in the ischemic injury zone was sampled using MRI-guided localization. The relative area of abnormal tissue, changes in PWI and DWI in the ischemic injury zone, and the number of apoptotic cells based on TdT-mediated dUTP-biotin nick end-labeling (TUNEL) were assessed. Our findings demonstrate that EPO reduces the relative area of abnormally high signal in PWI and DWI, increases cerebral blood volume, and decreases the number of apoptotic cells positive for TUNEL in the area injured by cerebral ischemia/reperfusion. The experiment provides imaging evidence in vivo for EPO treating cerebral ischemia/reperfusion injury.

  14. The therapeutic effect and prognosis of acute cerebral infarction patients with atrial fibrillation treated by intravenous thrombolysis with recombinant tissue plasminogen activator

    Institute of Scientific and Technical Information of China (English)

    尤寿江

    2013-01-01

    Objective To investigate the efficacy and safety of intravenous thrombolysis with recombinant tissue plasminogen activator (rt-PA) in acute cerebral infarct patients with atrial fibrillation (AF) and the predicting factors of poor prognosis.Methods Totally 162 patients with acute cerebral infarct were treated with rt-PA within 4.5hours from the onset.According to past history and the electrocardiogram,the patients was classified into AF

  15. Reduced blood flow response to acetazolamide reflects pre-existing vasodilation and decreased oxygen metabolism in major cerebral arterial occlusive disease

    Energy Technology Data Exchange (ETDEWEB)

    Yamauchi, Hiroshi; Okazawa, Hidehiko; Kishibe, Yoshihiko; Sugimoto, Kanji; Takahashi, Masaaki [Research Institute, Shiga Medical Center, 5-4-30 Moriyama, Moriyama-city, Shiga 524-8524 (Japan)

    2002-10-01

    A decrease in the cerebral blood flow (CBF) response to acetazolamide may indicate an increase in cerebral blood volume (CBV) caused by reduced perfusion pressure in patients with major cerebral artery steno-occlusive lesions. However, a decrease in cerebral metabolic rate of oxygen (CMRO{sub 2}) caused by ischemic changes may also decrease the CBF response to acetazolamide by decreasing the production of carbon dioxide. The purpose of this study was to determine whether the values of CBV and CMRO{sub 2} are independent predictors of the CBF response to acetazolamide in major cerebral arterial occlusive disease. We used positron emission tomography to study 30 patients with major cerebral artery steno-occlusive lesions. The CBF response to acetazolamide was assessed by measuring baseline CBF and CBF 10 min after an intravenous injection of 1 g of acetazolamide. Multivariate analysis was used to test the independent predictive value of the CBV and CMRO{sub 2} at baseline with respect to the percent change in CBF during acetazolamide administration. Both increased CBV and decreased CMRO{sub 2} were significant and independent predictors of the reduced CBF response to acetazolamide. CBV accounted for 25% of the variance in the absolute change in CBF during acetazolamide administration and 42% of the variance in the percent change in CBF, whereas CMRO{sub 2} accounted for 19% and 4% of the variance, respectively. In patients with major cerebral arterial occlusive disease, a decrease in CMRO{sub 2} may contribute to the reduced CBF response to acetazolamide, although an increase in CBV appears to be the major contributing factor. (orig.)

  16. Effect of oxygen breathing on micro oxygen bubbles in nitrogen-depleted rat adipose tissue at sea level and 25 kPa altitude exposures.

    Science.gov (United States)

    Randsoe, Thomas; Hyldegaard, Ole

    2012-08-01

    The standard treatment of altitude decompression sickness (aDCS) caused by nitrogen bubble formation is oxygen breathing and recompression. However, micro air bubbles (containing 79% nitrogen), injected into adipose tissue, grow and stabilize at 25 kPa regardless of continued oxygen breathing and the tissue nitrogen pressure. To quantify the contribution of oxygen to bubble growth at altitude, micro oxygen bubbles (containing 0% nitrogen) were injected into the adipose tissue of rats depleted from nitrogen by means of preoxygenation (fraction of inspired oxygen = 1.0; 100%) and the bubbles studied at 101.3 kPa (sea level) or at 25 kPa altitude exposures during continued oxygen breathing. In keeping with previous observations and bubble kinetic models, we hypothesize that oxygen breathing may contribute to oxygen bubble growth at altitude. Anesthetized rats were exposed to 3 h of oxygen prebreathing at 101.3 kPa (sea level). Micro oxygen bubbles of 500-800 nl were then injected into the exposed abdominal adipose tissue. The oxygen bubbles were studied for up to 3.5 h during continued oxygen breathing at either 101.3 or 25 kPa ambient pressures. At 101.3 kPa, all bubbles shrank consistently until they disappeared from view at a net disappearance rate (0.02 mm(2) × min(-1)) significantly faster than for similar bubbles at 25 kPa altitude (0.01 mm(2) × min(-1)). At 25 kPa, most bubbles initially grew for 2-40 min, after which they shrank and disappeared. Four bubbles did not disappear while at 25 kPa. The results support bubble kinetic models based on Fick's first law of diffusion, Boyles law, and the oxygen window effect, predicting that oxygen contributes more to bubble volume and growth during hypobaric conditions. As the effect of oxygen increases, the lower the ambient pressure. The results indicate that recompression is instrumental in the treatment of aDCS.

  17. Evaluation of tissue oxygen measurements for flap monitoring in an animal model

    DEFF Research Database (Denmark)

    Bonde, Christian; Elberg, Jens; Holstein-Rathlou, N.-H.

    2008-01-01

    Tissue oxygen tension (p(ti)O(2)) measurements are common in neurosurgery but uncommon in plastic surgery. We examined this technique as a monitoring method with probe placement in the subcutaneous tissue and addressed the importance of probe placement. Myocutaneous flaps were raised in an animal...... model and p(ti)O(2) measurements performed at different levels in the subcutaneous fat. Flap artery and vein were occluded until a 50% p(ti)O(2) reduction had occurred (T(1/2)). We found no significant effect of depth (P>0.10) on the level of p(ti)O(2). T(1/2)(arterial) was 7.2 minutes and T(1/2)(venous...... in the subcutaneous tissue and is highly sensitive to changes in both arterial and venous blood flow....

  18. Single-photon emission computed tomography and positron-emission tomography assays for tissue oxygenation.

    Science.gov (United States)

    Chapman, J D; Schneider, R F; Urbain, J L; Hanks, G E

    2001-01-01

    Radiotherapy prescription can now be customized to target the major mechanism(s) of resistance of individual tumors. In that regard, functional imaging techniques should be exploited to identify the dominant mechanism(s). Tumor biology research has identified several mechanisms of tumor resistance that may be unique to radiation treatments. These fall into 3 broad areas associated with (1) tumor hypoxic fraction, (2) tumor growth rate, (3) and the intrinsic radiosensitivity of tumor clonogens. Imaging research has markers in various stages of development for quantifying relevant information about each of these mechanisms, and those that measure tumor oxygenation and predict for radioresistance are the most advanced. Positron-emission tomography (PET) measurement of oxygen 15 has yielded important information, particularly about brain tissue perfusion, metabolism, and function. Indirect markers of tumor hypoxia have exploited the covalent binding of bioreductive intermediates of azomycin-containing compounds whose uptakes are inversely proportional to intracellular oxygen concentrations. Pilot clinical studies with single-photon emission computed tomography (SPECT) and PET detection of radiolabeled markers to tumor hypoxia have been reported. Recently, other studies have attempted to exploit the reduction properties of both technetium and copper chelates for the selective deposition of radioactive metals in hypoxic tissues. A growing number of potentially useful isotopes are now available for labeling several novel chemicals that could have the appropriate specificity and sensitivity. Preclinical studies with "microSPECT" and "microPET" will be important to define the optimal radiodiagnostic(s) for measuring tissue oxygenation and for determining the time after their administration for optimal hypoxic signal acquisition. Radiolabeled markers of growth kinetics and intrinsic radiosensitivity of cells in solid tumors are also being developed. We conclude that

  19. Tissue gas and blood analyses of human subjects breathing 80% argon and 20% oxygen

    Science.gov (United States)

    Horrigan, D. J.; Wells, C. H.; Guest, M. M.; Hart, G. B.; Goodpasture, J. E.

    1979-01-01

    Eight human volunteers, individually studied in a hyperbaric chamber, breathed: (1) air at 1 ATA; (2) 80% argon and 20% oxygen at 1 ATA for 30 min; (3) air at 1 ATA for 30 min; (4) 100% O2 at 1 ATA for 30 min; (5) air at 1 ATA for 30 min; (6) 100% O2 at 2 ATA for 60 min; and (7) 80% argon and 20% oxygen at 1 ATA for 30 min. Oxygen, carbon dioxide, nitrogen, and argon tensions were measured in muscle and subcutaneous tissue by mass spectroscopic analyses. Venous blood obtained at regular intervals was analyzed for coagulation and fibrinolytic factors. Inert gas narcosis was not observed. After breathing argon for 30 min, muscle argon tensions were almost three times the subcutaneous tensions. Argon wash-in mirrored nitrogen wash-out. Argon wash-in and wash-out had no effect on tissue PO2 or PCO2. Coagulation and fibrinolytic changes usually associated with vascular bubbles were absent.

  20. Effects of Repetitive Hyperbaric Oxygen Treatment in Patients with Acute Cerebral Infarction: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Cheng-Hsin Chen

    2012-01-01

    Full Text Available The role of hyperbaric oxygen therapy (HBOT in the treatment of acute ischemic stroke is controversial. This prospective study assessed the efficacy and safety of HBOT as adjuvant treatment on 46 acute ischemic stroke in patients who did not receive thrombolytic therapy. The HBOT group (n=16 received conventional medical treatment with 10 sessions of adjunctive HBOT within 3–5 days after stroke onset, while the control group (n=30 received the same treatment but without HBOT. Early (around two weeks after onset and late (one month after onset outcomes (National Institutes of Health Stroke Scale, NIHSS scores and efficacy (changes of NIHSS scores of HBOT were evaluated. The baseline clinical characteristics were similar in both groups. Both early and late outcomes of the HBOT group showed significant difference (P≤0.001. In the control group, there was only significant difference in early outcome (P=0.004. For early efficacy, there was no difference when comparing changes of NIHSS scores between the two groups (P=0.140 but there was statistically significant difference when comparing changes of NIHSS scores at one month (P≤0.001. The HBOT used in this study may be effective for patients with acute ischemic stroke and is a safe and harmless adjunctive treatment.

  1. Effect of oxygen and heliox breathing on air bubbles in adipose tissue during 25-kPa altitude exposures

    DEFF Research Database (Denmark)

    Randsoe, T.; Kvist, T.M.; Hyldegaard, O.

    2008-01-01

    and heliox breathing. Preoxygenation enhanced bubble disappearance compared with oxygen and heliox breathing but did not prevent bubble growth. The results indicate that oxygen breathing at 25 kPa promotes air bubble growth in adipose tissue regardless of the tissue nitrogen pressure Udgivelsesdato: 2008/11......At altitude, bubbles are known to form and grow in blood and tissues causing altitude decompression sickness. Previous reports indicate that treatment of decompression sickness by means of oxygen breathing at altitude may cause unwanted bubble growth. In this report we visually followed the in vivo.......7) after which they started shrinking or remained stable throughout the observation period. Bubble growth time was significantly longer during oxygen breathing compared with heliox breathing and preoxygenated animals. Significantly more bubbles disappeared in preoxygenated animals compared with oxygen...

  2. Gadd45b prevents autophagy and apoptosis against rat cerebral neuron oxygen-glucose deprivation/reperfusion injury.

    Science.gov (United States)

    He, Guoqian; Xu, Wenming; Tong, Linyan; Li, Shuaishuai; Su, Shiceng; Tan, Xiaodan; Li, Changqing

    2016-04-01

    Autophagic (type II) cell death has been suggested to play pathogenetic roles in cerebral ischemia. Growth arrest and DNA damage response 45b (Gadd45b) has been shown to protect against rat brain ischemia injury through inhibiting apoptosis. However, the relationship between Gadd45b and autophagy in cerebral ischemia/reperfusion (I/R) injury remains uncertain. The aim of this study is to investigate the effect of Gadd45b on autophagy. We adopt the oxygen-glucose deprivation and reperfusion (OGD/R) model of rat primary cortex neurons, and lentivirus interference used to silence Gadd45b expression. Cell viability and injury assay were performed using CCK-8 and LDH kit. Autophagy activation was monitored by expression of ATG5, LC3, Beclin-1, ATG7 and ATG3. Neuron apoptosis was monitored by expression of Bcl-2, Bax, cleaved caspase3, p53 and TUNEL assay. Neuron neurites were assayed by double immunofluorescent labeling with Tuj1 and LC3B. Here, we demonstrated that the expression of Gadd45b was strongly up-regulated at 24 h after 3 h OGD treatment. ShRNA-Gadd45b increased the expression of autophagy related proteins, aggravated OGD/R-induced neuron cell apoptosis and neurites injury. ShRNA-Gadd45b co-treatment with autophagy inhibitor 3-methyladenine (3-MA) or Wortmannin partly inhibited the ratio of LC3II/LC3I, and slightly ameliorated neuron cell apoptosis under OGD/R. Furthermore, shRNA-Gadd45b inhibited the p-p38 level involved in autophagy, but increased the p-JNK level involved in apoptosis. ShRNA-Gadd45b co-treatment with p38 inhibitor obviously induced autophagy. ShRNA-Gadd45b co-treatment with JNK inhibitor alleviated neuron cell apoptosis. In conclusion, our data suggested that Gadd45b inhibited autophagy and apoptosis under OGD/R. Gadd45b may be a common regulatory protein to control autophagy and apoptosis.

  3. Brain tissue oxygen-based therapy and outcome after severe traumatic brain injury: a systematic literature review.

    Science.gov (United States)

    Nangunoori, Raj; Maloney-Wilensky, Eileen; Stiefel, Michael; Park, Soojin; Andrew Kofke, W; Levine, Joshua M; Yang, Wei; Le Roux, Peter D

    2012-08-01

    Observational clinical studies demonstrate that brain hypoxia is associated with poor outcome after severe traumatic brain injury (TBI). In this study, available medical literature was reviewed to examine whether brain tissue oxygen (PbtO2)-based therapy is associated with improved patient outcome after severe TBI. Clinical studies published between 1993 and 2010 that compared PbtO2-based therapy combined with intracranial and cerebral perfusion pressure (ICP/CPP)-based therapy to ICP/CPP-based therapy alone were identified from electronic databases, Index Medicus, bibliographies of pertinent articles, and expert consultation. For analysis, each selected paper had to have adequate data to determine odds ratios (ORs) and confidence intervals (CIs) of outcome described by the Glasgow outcome score (GOS). Seven studies that compared ICP/CPP and PbtO2- to ICP/CPP-based therapy were identified. There were no randomized studies and no comparison studies in children. Four studies, published in 2003, 2009, and 2010 that included 491 evaluable patients were used in the final analysis. Among patients who received PbtO2-based therapy, 121(38.8%) had unfavorable and 191 (61.2%) had a favorable outcome. Among the patients who received ICP/CPP-based therapy 104 (58.1%) had unfavorable and 75 (41.9%) had a favorable outcome. Overall PbtO2-based therapy was associated with favorable outcome (OR 2.1; 95% CI 1.4-3.1). Summary results suggest that combined ICP/CPP- and PbtO2-based therapy is associated with better outcome after severe TBI than ICP/CPP-based therapy alone. Cross-organizational practice variances cannot be controlled for in this type of review and so we cannot answer whether PbtO2-based therapy improves outcome. However, the potentially large incremental value of PbtO2-based therapy provides justification for a randomized clinical trial.

  4. Influence of oxygen tension on myocardial performance. Evaluation by tissue Doppler imaging

    Directory of Open Access Journals (Sweden)

    Poulsen Steen

    2004-11-01

    Full Text Available Abstract Background Low O2 tension dilates coronary arteries and high O2 tension is a coronary vasoconstrictor but reports on O2-dependent effects on ventricular performance diverge. Yet oxygen supplementation remains first line treatment in cardiovascular disease. We hypothesized that hypoxia improves and hyperoxia worsens myocardial performance. Methods Seven male volunteers (mean age 38 ± 3 years were examined with echocardiography at respiratory equilibrium during: 1 normoxia (≈21% O2, 79% N2, 2 while inhaling a hypoxic gas mixture (≈11% O2, 89% N2, and 3 while inhaling 100% O2. Tissue Doppler recordings were acquired in the apical 4-chamber, 2-chamber, and long-axis views. Strain rate and tissue tracking displacement analyses were carried out in each segment of the 16-segment left ventricular model and in the basal, middle and apical portions of the right ventricle. Results Heart rate increased with hypoxia (68 ± 4 bpm at normoxia vs. 79 ± 5 bpm, P Conclusion Hypoxia improves and hyperoxia worsens systolic myocardial performance in healthy male volunteers. Tissue Doppler measures of diastolic function are unaffected by hypoxia/hyperoxia which support that the changes in myocardial performance are secondary to changes in vascular tone. It remains to be settled whether oxygen therapy to patients with heart disease is a consistent rational treatment.

  5. The use of visible light spectroscopy to measure tissue oxygenation in free flap reconstruction.

    Science.gov (United States)

    Cornejo, Agustin; Rodriguez, Thomas; Steigelman, Megan; Stephenson, Stacy; Sahar, David; Cohn, Stephen M; Michalek, Joel E; Wang, Howard T

    2011-09-01

    The loss of a free flap is a feared complication for both the surgeon and the patient. Early recognition of vascular compromise has been shown to provide the best chance for flap salvage. The ideal monitoring technique for perioperative free flap ischemia would be noninvasive, continuous, and reliable. Visible light spectroscopy (VLS) was evaluated as a new method for predicting ischemia in microvascular cutaneous soft tissue free flaps. In an Institutional Review Board-approved prospective trial, 12 patients were monitored after free flap reconstructions. The tissue hemoglobin oxygen saturation (StO (2)) and total hemoglobin concentration (THB) of 12 flaps were continuously monitored using VLS for 72 hours postoperatively. Out of these 12 flaps 11 were transplanted successfully and 1 flap loss occurred. The StO (2 )was 48.99% and the THB was 46.74% for the 12 flaps. There was no significant difference in these values among the flaps. For the single flap loss, the device accurately reflected the ischemic drop in StO (2) indicating drastic tissue ischemia at 6 hours postoperatively before the disappearance of implantable Doppler signals or clinical signs of flap compromise. VLS, a continuous, noninvasive, and localized method to monitor oxygenation, appeared to predict early ischemic complications after free flap reconstruction.

  6. Acute effects of nicotine and smoking on blood flow, tissue oxygen, and aerobe metabolism of the skin and subcutis

    DEFF Research Database (Denmark)

    Sørensen, Lars Tue; Jørgensen, Stig; Petersen, Lars J

    2009-01-01

    and subcutaneous blood flow (QBF, SqBF) was assessed by Laser Doppler and 133Xe clearance. Tissue oxygen tension (TO(2)) was measured by a LICOX O(2)-electrode. Tissue glucose and lactate (Tgluc, Tlact) were assessed by microdialysis. The parameters were studied after intravenous infusion of 1.0 mg nicotine......, smoking of one cigarette, arterial occlusion, and reperfusion. RESULTS: Nicotine infusion decreased SqBF from 4.2 +/- 2.0 to 3.1 +/- 1.2 mL/100 g tissue/min (P ... by smoking, which distinctly decreases tissue blood flow, oxygen tension, and aerobe metabolism independent of smoking status....

  7. Blood flow and oxygenation in peritendinous tissue and calf muscle during dynamic exercise in humans

    DEFF Research Database (Denmark)

    Boushel, R; Langberg, Henning; Green, Stefan Mathias;

    2000-01-01

    1. Circulation around tendons may act as a shunt for muscle during exercise. The perfusion and oxygenation of Achilles' peritendinous tissue was measured in parallel with that of calf muscle during exercise to determine (1) whether blood flow is restricted in peritendinous tissue during exercise......, and (2) whether blood flow is coupled to oxidative metabolism. 2. Seven individuals performed dynamic plantar flexion from 1 to 9 W. Radial artery and popliteal venous blood were sampled for O2, peritendinous blood flow was determined by 133Xe-washout, calf blood flow by plethysmography, cardiac output...... by dye dilution, arterial pressure by an arterial catheter-transducer, and muscle and peritendinous O2 saturation by spatially resolved spectroscopy (SRS). 3. Calf blood flow rose 20-fold with exercise, reaching 44 +/- 7 ml (100 g)-1 min-1 (mean +/- s.e.m. ) at 9 W, while Achilles' peritendinous flow...

  8. Multi-modal assessment of neurovascular coupling during cerebral ischaemia and reperfusion using remote middle cerebral artery occlusion

    DEFF Research Database (Denmark)

    Sutherland, Brad A; Fordsmann, Jonas C; Martin, Chris;

    2016-01-01

    how neurovascular coupling is affected hyperacutely during cerebral ischaemia and reperfusion. We have developed a remote middle cerebral artery occlusion model in the rat, which enables multi-modal assessment of neurovascular coupling immediately prior to, during and immediately following reperfusion....... Male Wistar rats were subjected to remote middle cerebral artery occlusion, where a long filament was advanced intraluminally through a guide cannula in the common carotid artery. Transcallosal stimulation evoked increases in blood flow, tissue oxygenation and neuronal activity, which were diminished...... by middle cerebral artery occlusion and partially restored during reperfusion. These evoked responses were not affected by administration of the thrombolytic alteplase at clinically used doses. Evoked cerebral blood flow responses were fully restored at 24 h post-middle cerebral artery occlusion indicating...

  9. Effects of oxygen and glucose deprivation on the expression and distribution of neuronal and inducible nitric oxide synthases and on protein nitration in rat cerebral cortex.

    Science.gov (United States)

    Alonso, David; Serrano, Julia; Rodríguez, Ignacio; Ruíz-Cabello, Jesús; Fernández, Ana Patricia; Encinas, Juan Manuel; Castro-Blanco, Susana; Bentura, María Luisa; Santacana, María; Richart, Ana; Fernández-Vizarra, Paula; Uttenthal, Lars Otto; Rodrigo, José

    2002-02-04

    Changes in the nitric oxide (NO) system of the rat cerebral cortex were investigated by immunohistochemistry, immunoblotting, NO synthase (NOS) activity assay, and magnetic resonance imaging (MRI) in an experimental model of global cerebral ischemia and reperfusion. Brains were perfused transcardially with an oxygenated plasma substitute and subjected to 30 minutes of oxygen and glucose deprivation, followed by reperfusion for up to 12 hours with oxygenated medium containing glucose. A sham group was perfused without oxygen or glucose deprivation, and a further group was treated with the NOS inhibitor N(omega)-nitro-L-arginine methyl ester (L-NAME) before and during perfusion. Global ischemia led to cerebrocortical injury as shown by diffusion MRI. This was accompanied by increasing morphologic changes in the large type I interneurons expressing neuronal NOS (nNOS) and the appearance of nNOS immunoreactivity in small type II neurons. The nNOS-immunoreactive band and calcium-dependent NOS activity showed an initial increase, followed by a fall after 6 hours of reperfusion. Inducible NOS immunoreactivity appeared in neurons, especially pyramidal cells of layers IV-V, after 4 hours of reperfusion, with corresponding changes on immunoblotting and in calcium-independent NOS activity. Immunoreactive protein nitrotyrosine, present in the nuclear area of neurons in nonperfused controls and sham-perfused animals, showed changes in intensity and distribution, appearing in the neuronal processes during the reperfusion period. Prior and concurrent L-NAME administration blocked the changes on diffusion MRI and attenuated the morphologic changes, suggesting that NO and consequent peroxynitrite formation during ischemia-reperfusion contributes to cerebral injury.

  10. In vivo evidence of methamphetamine induced attenuation of brain tissue oxygenation as measured by EPR oximetry

    Energy Technology Data Exchange (ETDEWEB)

    Weaver, John, E-mail: jmweaver@salud.unm.edu [Center of Biomedical Research Excellence, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Yang, Yirong [Center of Biomedical Research Excellence, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Purvis, Rebecca [Center of Biomedical Research Excellence, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Department of Neurology, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Weatherwax, Theodore [Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Rosen, Gerald M. [Center for Biomedical Engineering and Technology, University of Maryland, Baltimore, MD 21201 (United States); Center for EPR Imaging In Vivo Physiology, University of Maryland, Baltimore, MD 21201 (United States); Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, MD 21201 (United States); Liu, Ke Jian [Center of Biomedical Research Excellence, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Department of Neurology, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States)

    2014-03-01

    Abuse of methamphetamine (METH) is a major and significant societal problem in the US, as a number of studies have suggested that METH is associated with increased cerebrovascular events, hemorrhage or vasospasm. Although cellular and molecular mechanisms involved in METH-induced toxicity are not completely understood, changes in brain O{sub 2} may play an important role and contribute to METH-induced neurotoxicity including dopaminergic receptor degradation. Given that O{sub 2} is the terminal electron acceptor for many enzymes that are important in brain function, the impact of METH on brain tissue pO{sub 2}in vivo remains largely uncharacterized. This study investigated striatal tissue pO{sub 2} changes in male C57BL/6 mice (16–20 g) following METH administration using EPR oximetry, a highly sensitive modality to measure pO{sub 2}in vivo, in situ and in real time. We demonstrate that 20 min after a single injection of METH (8 mg/kg i.v.), the striatal pO{sub 2} was reduced to 81% of the pretreatment level and exposure to METH for 3 consecutive days further attenuated striatal pO{sub 2} to 64%. More importantly, pO{sub 2} did not recover fully to control levels even 24 h after administration of a single dose of METH and continual exposure to METH exacerbates the condition. We also show a reduction in cerebral blood flow associated with a decreased brain pO{sub 2} indicating an ischemic condition. Our findings suggests that administration of METH can attenuate brain tissue pO{sub 2}, which may lead to hypoxic insult, thus a risk factor for METH-induced brain injury and the development of stroke in young adults. - Highlights: • Explored striatal tissue pO{sub 2}in vivo after METH administration by EPR oximetry. • pO{sub 2} was reduced by 81% after a single dose and 64% after 3 consecutive daily doses. • pO{sub 2} did not recover fully to control levels even 24 h after a single dose. • Decrease in brain tissue pO{sub 2} may be associated with a decrease in

  11. Neuroprotective effects of the AMPA antagonist PNQX in oxygen-glucose deprivation in mouse hippocampal slice cultures and global cerebral ischemia in gerbils

    DEFF Research Database (Denmark)

    Montero, Maria; Nielsen, Marianne; Rønn, Lars Christian B;

    2007-01-01

    PNQX (9-methyl-amino-6-nitro-hexahydro-benzo(F)quinoxalinedione) is a selective AMPA antagonist with demonstrated neuroprotective effects in focal ischemia in rats. Here we report corresponding effects in mouse hippocampal slice cultures subjected to oxygen and glucose deprivation (OGD......) and in transient global cerebral ischemia in gerbils. For in vitro studies, hippocampal slice cultures derived from 7-day-old mice and grown for 14 days, were submersed in oxygen-glucose deprived medium for 30 min and exposed to PNQX for 24 h, starting together with OGD, immediately after OGD, or 2 h after OGD...... ischemia in gerbils in vivo and oxygen-glucose deprivation in mouse hippocampal slice cultures....

  12. Nanoparticle-enhanced spectral photoacoustic tomography: effect of oxygen saturation and tissue heterogeneity

    Science.gov (United States)

    Vogt, William C.; Jia, Congxian; Wear, Keith A.; Garra, Brian S.; Pfefer, T. Joshua

    2016-03-01

    Molecular imaging for breast cancer detection, infectious disease diagnostics and preclinical animal research may be achievable through combined use of targeted exogenous agents - such as nanoparticles - and spectral Photoacoustic Tomography (PAT). However, tissue heterogeneity can alter fluence distributions and acoustic propagation, corrupting measured PAT absorption spectra and complicating in vivo nanoparticle detection and quantitation. Highly absorptive vascular structures represent a common confounding factor, and variations in vessel hemoglobin saturation (SO2) may alter spectral content of signals from adjacent/deeper regions. To evaluate the impact of this effect on PAT nanoparticle detectability, we constructed heterogeneous phantoms with well-characterized channel-inclusion geometries and biologically relevant optical and acoustic properties. Phantoms contained an array of tubes at several depths filled with hemoglobin solutions doped with varying concentrations of gold nanorods with an absorption peak at 780 nm. Both overlying and target network SO2 was tuned using sodium dithionite. Phantoms were imaged from 700 to 900 nm using a custom PAT system comprised of a tunable pulsed laser and a research-grade ultrasound system. Recovered nanoparticle spectra were analyzed and compared with results from both spectrophotometry and PAT data from waterimmersed tubes containing blood and nanoparticle solutions. Results suggested that nanoparticle selection for a given PAT application should take into account expected oxygenation states of both target blood vessel and background tissue oxygenation to achieve optimal performance.

  13. Multichannel near infrared spectroscopy indicates regional variations in cerebral autoregulation in infants supported on extracorporeal membrane oxygenation

    Science.gov (United States)

    Papademetriou, Maria D.; Tachtsidis, Ilias; Elliot, Martin J.; Hoskote, Aparna; Elwell, Clare E.

    2012-06-01

    Assessing noninvasively cerebral autoregulation, the protective mechanism of the brain to maintain constant cerebral blood flow despite changes in blood pressure, is challenging. Infants on life support system (ECMO) for cardiorespiratory failure are at risk of cerebral autoregulation impairment and consequent neurological problems. We measured oxyhaemoglobin concentration (HbO2) by multichannel (12 channels) near-infrared spectroscopy (NIRS) in six infants during sequential changes in ECMO flow. Wavelet cross-correlation (WCC) between mean arterial pressure (MAP) and HbO2 was used to construct a time-frequency representation of the concordance between the two signals to assess the nonstationary aspect of cerebral autoregulation and investigate regional variations. Group data showed that WCC increases with decreasing ECMO flow indicating higher concordance between MAP and HbO2 and demonstrating loss of cerebral autoregulation at low ECMO flows. Statistically significant differences in WCC were observed between channels placed on the right and left scalp with channels on the right exhibiting higher values of WCC suggesting that the right hemisphere was more susceptible to disruption of cerebral autoregulation. Multichannel NIRS in conjunction with wavelet analysis methods can be used to assess regional variations in dynamic cerebral autoregulation with important clinical application in the management of critically ill children on life support systems.

  14. Enhanced cerebrovascular expression of matrix metalloproteinase-9 and tissue inhibitor of metalloproteinase-1 via the MEK/ERK pathway during cerebral ischemia in the rat

    DEFF Research Database (Denmark)

    Maddahi, Aida; Chen, Qingwen; Edvinsson, Lars

    2009-01-01

    of metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinase-1 (TIMP-1). RESULTS: Here, we found an infarct volume of 24.8 +/- 2% and a reduced neurological function after two hours of middle cerebral artery occlusion (MCAO), followed by 48 hours of recirculation in rat. Immunocytochemistry and confocal...

  15. Multisite Tissue Oxygenation Monitoring Indicates Organ-Specific Flow Distribution and Oxygen Delivery Related to Low Cardiac Output in Preterm Infants With Clinical Sepsis

    NARCIS (Netherlands)

    van der Laan, Michelle E.; Roofthooft, Marcus T. R.; Fries, Marian W. A.; Schat, Trijntje E.; Bos, Arend F.; Berger, Rolf M. F.; Kooi, Elisabeth M. W.

    2016-01-01

    Objectives: Cardiac output may be compromised in preterm infants with sepsis. Whether low cardiac output is associated with low tissue oxygen supply in these patients is unclear. The aim of the current study was to assess the association between cardiac output, assessed by echocardiography, and tiss

  16. Effects of the Oxygen-Carrying Solution OxyVita C on the Cerebral Microcirculation and Systemic Blood Pressures in Healthy Rats

    Directory of Open Access Journals (Sweden)

    Rania Abutarboush

    2014-11-01

    Full Text Available The use of hemoglobin-based oxygen carriers (HBOC as oxygen delivering therapies during hypoxic states has been hindered by vasoconstrictive side effects caused by depletion of nitric oxide (NO. OxyVita C is a promising oxygen-carrying solution that consists of a zero-linked hemoglobin polymer with a high molecular weight (~17 MDa. The large molecular weight is believed to prevent extravasation and limit NO scavenging and vasoconstriction. The aim of this study was to assess vasoactive effects of OxyVita C on systemic blood pressures and cerebral pial arteriole diameters. Anesthetized healthy rats received four intravenous (IV infusions of an increasing dose of OxyVita C (2, 25, 50, 100 mg/kg and hemodynamic parameters and pial arteriolar diameters were measured pre- and post-infusion. Normal saline was used as a volume-matched control. Systemic blood pressures increased (P ≤ 0.05 with increasing doses of OxyVita C, but not with saline. There was no vasoconstriction in small (<50 µm and medium-sized (50–100 µm pial arterioles in the OxyVita C group. In contrast, small and medium-sized pial arterioles vasoconstricted in the control group. Compared to saline, OxyVita C showed no cerebral vasoconstriction after any of the four doses evaluated in this rat model despite increases in blood pressure.

  17. Neuroprotective effect of high-dose hyperbaric oxygenation on rats with acute cerebral infarction in super-early stage Curative comparison between 9-hour and 18-hour therapeutic protocols

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    BACKGROUND: Previously, only single short-time low-dose hyperbaric oxygenation (HBO) protocol was administrated to treat acute ischemic stroke in early stage and the conflicting results were obtained. There are few studies to report the outcome of administering long-time (can cover all the natural pathologic progression period) high-dose HBO to treat the disease.OBJECTIVE: To evaluate the therapeutic effect between two kinds of high-dose hyperbaric oxygenation on super-early stage of acute permanent middle cerebral artery occlusion (MCAO) in rats.DESIGN: A randomized controlled experimental study.SETTING: Beijing Tiantan Hospital, Capital Medical University; Beijing Research Institute of Neurosurgery.MATERIALS: Seventy-four male SD rats, aged 2.5 months old, weighing (280±20) g, were provided by the Animal Institute, Chinese Academy of Medical Sciences. Hyperbaric oxygenation device was hyperbaric air cabin in which there was a self-made pure oxygen animal experimental cabin (made in China).METHODS: This experiment was carried out in the municipal laboratory of Beijing Tiantan Hospital affiliated to Capital Medical University and Beijing Research Institute of Neurosurgery. ① Experimental intervention: All the rats were developed into models of permanent MCAO by suture embolism. Then, they were randomly divided into two HBO groups (9hours and 18 hours) and control group, with 24 rats in each as well as 3-hour ultrastructure control group, with 2 rats. After being modeled for 3 hours, rats in the two HBO groups stayed in the hyperbaric cabin for 9 hours and 18 hours,separately. Rats in the 9-hour HBO group inhaled pure oxygen at hours 1, 3, 5, 7 and 9, and hyperbaric air at hours 2, 4, 6 and 8. Rats in the 18-hour HBO group inhaled pure oxygen at hours 1, 3, 5, 7, 9, 11, 13, 15 and 17, and hyperbaric air at hours 2, 4, 6, 8, 10 12, 14, 16 and 18. After being created into models, rats in the control group and 3-hour ultrastructure control group breathed room air.

  18. Cerebral oxygenation after birth

    DEFF Research Database (Denmark)

    Hessel, Trine W; Hyttel-Sorensen, Simon; Greisen, Gorm

    2014-01-01

    .19 p = 86.2% (CI 85.0-87.4%) for INVOS and FORE-SIGHT, respectively. The within-subject standard deviation during steady-state repeated measurements was 4.8% ± 0.86 for INVOS and 2.8% ± 0.5 for FORE-SIGHT. CONCLUSION...

  19. Non-Invasive, Simultaneous Quantification of Vascular Oxygenation and Glucose Uptake in Tissue

    Science.gov (United States)

    Rajaram, Narasimhan; Reesor, Andrew F.; Mulvey, Christine S.; Frees, Amy E.; Ramanujam, Nirmala

    2015-01-01

    We report the development of non-invasive, fiber-based diffuse optical spectroscopy for simultaneously quantifying vascular oxygenation (SO2) and glucose uptake in solid tumors in vivo. Glucose uptake was measured using a fluorescent glucose analog, 2-[N-(7-nitrobenz-2-oxa-1,3-diaxol-4-yl)amino]-2-deoxyglucose (2-NBDG). Quantification of label-free SO2 and 2-NBDG-fluorescence-based glucose uptake 60 minutes after administration of the tracer (2-NBDG60) was performed using computational models of light-tissue interaction. This study was carried out on normal tissue and 4T1 and 4T07 murine mammary tumor xenografts in vivo. Injection of 2-NBDG did not cause a significant change in optical measurements of SO2, demonstrating its suitability as a functional reporter of tumor glucose uptake. Correction of measured 2-NBDG-fluorescence for the effects of absorption and scattering significantly improved contrast between tumor and normal tissue. The 4T1 and 4T07 tumors showed significantly decreased SO2, and 4T1 tumors demonstrated increased 2-NBDG60 compared with normal tissue (60 minutes after the administration of 2-NBDG when perfusion-mediated effects have cleared). 2-NBDG-fluorescence was found to be highly sensitive to food deprivation-induced reduction in blood glucose levels, demonstrating that this endpoint is indeed sensitive to glycolytic demand. 2-NBDG60 was also found to be linearly related to dose, underscoring the importance of calibrating for dose when comparing across animals or experiments. 4T1 tumors demonstrated an inverse relationship between 2-NBDG60 and SO2 that was consistent with the Pasteur effect, particularly when exposed to hypoxic gas breathing. Our results illustrate the potential of optical spectroscopy to provide valuable information about the metabolic status of tumors, with important implications for cancer prognosis. PMID:25635865

  20. Non-invasive, simultaneous quantification of vascular oxygenation and glucose uptake in tissue.

    Directory of Open Access Journals (Sweden)

    Narasimhan Rajaram

    Full Text Available We report the development of non-invasive, fiber-based diffuse optical spectroscopy for simultaneously quantifying vascular oxygenation (SO2 and glucose uptake in solid tumors in vivo. Glucose uptake was measured using a fluorescent glucose analog, 2-[N-(7-nitrobenz-2-oxa-1,3-diaxol-4-ylamino]-2-deoxyglucose (2-NBDG. Quantification of label-free SO2 and 2-NBDG-fluorescence-based glucose uptake 60 minutes after administration of the tracer (2-NBDG60 was performed using computational models of light-tissue interaction. This study was carried out on normal tissue and 4T1 and 4T07 murine mammary tumor xenografts in vivo. Injection of 2-NBDG did not cause a significant change in optical measurements of SO2, demonstrating its suitability as a functional reporter of tumor glucose uptake. Correction of measured 2-NBDG-fluorescence for the effects of absorption and scattering significantly improved contrast between tumor and normal tissue. The 4T1 and 4T07 tumors showed significantly decreased SO2, and 4T1 tumors demonstrated increased 2-NBDG60 compared with normal tissue (60 minutes after the administration of 2-NBDG when perfusion-mediated effects have cleared. 2-NBDG-fluorescence was found to be highly sensitive to food deprivation-induced reduction in blood glucose levels, demonstrating that this endpoint is indeed sensitive to glycolytic demand. 2-NBDG60 was also found to be linearly related to dose, underscoring the importance of calibrating for dose when comparing across animals or experiments. 4T1 tumors demonstrated an inverse relationship between 2-NBDG60 and SO2 that was consistent with the Pasteur effect, particularly when exposed to hypoxic gas breathing. Our results illustrate the potential of optical spectroscopy to provide valuable information about the metabolic status of tumors, with important implications for cancer prognosis.

  1. A pilot study of a new spectrophotometry device to measure tissue oxygen saturation.

    Science.gov (United States)

    Abel, Gemma; Allen, John; Drinnan, Michael

    2014-09-01

    Tissue oxygen saturation (SO2) measurements have the potential for far wider use than at present but are limited by device availability and portability for many potential applications. A device based on a small, low-cost general-purpose spectrophotometer (the Harrison device) might facilitate wider use. The aim of this study was to compare the Harrison device with a commercial instrument, the LEA O2C.Measurements were carried out on the forearm and finger of 20 healthy volunteers, using a blood pressure cuff on the upper arm to induce different levels of oxygenation. Repeatability of both devices was assessed, and the Bland-Altman method was used to assess agreement between them.The devices showed agreement in overall tracking of changes in SO2. Test-retest agreement for the Harrison device was worse than for O2C, with SD repeatability of 10.6% (forearm) or 18.6% (finger). There was no overall bias between devices, but mean (SD) difference of 1.2 (11.8%) (forearm) or 4.4 (11.5%) (finger) were outside of a clinically acceptable range.Disagreements were attributed to the stability of the Harrison probe and the natural SO2 variations across the skin surface increasing the random error. Therefore, though not equivalent to the LEA O2C, a probe redesign and averaged measurements may help establish the Harrison device as a low cost alternative.

  2. Influence of mild hypothermia on vascular endothelial growth factor and infarct volume in brain tissues after cerebral ischemia in rats

    Institute of Scientific and Technical Information of China (English)

    Fei Ye; Gangming Xi; Biyong Qin; Shifeng Wang; Chengyan Li

    2006-01-01

    BACKGROUND: It has been demonstrated that mild hypothermia has obvious protective effect on both whole and local cerebral ischemia. However, the definite mechanism is still unclear for the brain protection of mild hypothermia on cerebral edema, inhibiting inflammatory reaction, stabilizing blood brain barrier, etc.OBJECTIVE: To investigate the effect of mild hypothermia on the expression of vascular endothelial growth factor and the infarct volume after cerebral ischemia in rats, and analyze the brain protective mechanism of mild hypothermia.DESIGN: A randomized grouping and controlled animal trial.SETTING: Department of Neurology, People's Hospital of Yunyang Medical College.MATERIALS: Twenty adult male SD rats of clean degree, weighing (250±30) g, were provided by the animal experimental center, School of Medicine, Wuhan University. The kits for SP immunohistochemistry were purchased from Beijing Zhongshan Golden Bridge Biotechnology Co., Ltd.METHODS: The experiments were carried out in the laboratory of Department of Neurology, Renmen Hospital of Wuhan University from May to July 2005. ① The 20 rats were divided randomly into normal temperature group (n =10) and mild hypothermia group (n =10). Models of permanent middle cerebral artery occlusion were established with modified nylon suture embolization. The rats were assessed with the Longa standards: O point for without nerve dysfunction; 1 for mild neurological deficit (fore claws could no extend completely); 2 for moderate neurological deficit (circling towards the affected side); 3 for severe neurological deficit (tilting towards the affected side); 4 for coma and unconscious; 1 -3 points represented that models were successfully established. The rats of the normal temperature group were fed at room temperature, and those in the mild hypothermia group were induced by hypothermia from 2 hours postoperatively, and the rectal temperature was kept at 34-35 ℃ for 72 hours. ② Measurement of infarct volume

  3. Effects of Electroacupuncture plus Intra-carotid Drug Injection on Rheoencephalogram in Patients with Cerebral Infarction

    Institute of Scientific and Technical Information of China (English)

    李江明; 胡永均; 童利民; 王大军; 张道敬

    2004-01-01

    Purpose: To investigate the mechanism of electroacupuncture (EA) plus intra-carotid drug injection for treating cerebral infarction. Methods: Rheoencephalogram was recorded with a RG-2B type of bridge rheoencephalograph and findings were compared before and after the treatment. Results: After the treatment, the prolonged rising time was shortened, and the decreased amplitude obviously elevated. Conclusion: The therapy can dilate cerebral blood vessels, increase the cerebral blood flow, and improve the elasticity of cerebral blood vessels, leading to sufficient blood and oxygen supply in the ischemic brain tissues and to restoration of their functions.

  4. Regional differences in the coupling of cerebral blood flow and oxygen metabolism changes in response to activation: implications for BOLD-fMRI.

    Science.gov (United States)

    Ances, Beau M; Leontiev, Oleg; Perthen, Joanna E; Liang, Christine; Lansing, Amy E; Buxton, Richard B

    2008-02-15

    Functional magnetic resonance imaging (fMRI) based on blood oxygenation level dependent (BOLD) signal changes is a sensitive tool for mapping brain activation, but quantitative interpretation of the BOLD response is problematic. The BOLD response is primarily driven by cerebral blood flow (CBF) changes, but is moderated by M, a scaling parameter reflecting baseline deoxyhemoglobin, and n, the ratio of fractional changes in CBF to cerebral metabolic rate of oxygen consumption (CMRO(2)). We compared M and n between cortical (visual cortex, VC) and subcortical (lentiform nuclei, LN) regions using a quantitative approach based on calibrating the BOLD response with a hypercapnia experiment. Although M was similar in both regions (~5.8%), differences in n (2.21+/-0.03 in VC and 1.58+/-0.03 in LN; Cohen d=1.71) produced substantially weaker (~3.7x) subcortical than cortical BOLD responses relative to CMRO(2) changes. Because of this strong sensitivity to n, BOLD response amplitudes cannot be interpreted as a quantitative reflection of underlying metabolic changes, particularly when comparing cortical and subcortical regions.

  5. Cerebral blood flow and oxygen metabolism in patients with dementia of the Alzheimer's type by position emission tomography using 0-15 steady state technique

    Energy Technology Data Exchange (ETDEWEB)

    Sakamoto, Shizuki; Kitamura, Shin; Ujike, Takashi; Terashi, Akiro; Iio, Masaaki.

    1988-07-01

    In 12 patients with dementia of the Alzheimer's type (DAT) and 5 age-matched healthy subjects, regional cerebral blood flow (rCBF), oxygen extraction fraction (rOEF), and cerebral oxygen consumption (rCMRO/sub 2/) were determined using positron emission tomography (PET) with 0-15 labeled CO/sub 2/ and O/sub 2/ inhalation method. There was a significant reduction in CMRO/sub 2/ of the temporal cortex in the group of mild DAT compared with the control group. In the group of moderate DAT, CBF of the temporal cortex and CMRO/sub 2/ of the temporal and parietal cortices were significantly reduced. The group of severe DAT showed a significantly reduced CBF and CMRO/sub 2/ in the frontal cortex, and a relatively spared occipital cortex in all stages. The results indicated that metabolic reduction in the temporal cortex first occurs, and that metabolic dysfunction in the parietal and frontal cortices results in blood flow reduction and deterioration of DAT. Right/left metabolic asymmetry in the temporal and parietal cortices was correlated with language and visuospatial functions. (Namekawa, K).

  6. Repetitive Transcranial Magnetic Stimulation Changes Cerebral Oxygenation on the Left Dorsolateral Prefrontal Cortex in Bulimia Nervosa: A Near-Infrared Spectroscopy Pilot Study.

    Science.gov (United States)

    Sutoh, Chihiro; Koga, Yasuko; Kimura, Hiroshi; Kanahara, Nobuhisa; Numata, Noriko; Hirano, Yoshiyuki; Matsuzawa, Daisuke; Iyo, Masaomi; Nakazato, Michiko; Shimizu, Eiji

    2016-01-01

    Previous studies showed that food craving in eating disorders can be weakened with high-frequency repetitive transcranial magnetic stimulation (rTMS) on the left dorsolateral prefrontal cortex (DLPFC). The aims of this study were to assess cerebral oxygenation change induced with rTMS and to assess the short-term impact of rTMS on food craving and other bulimic symptoms in patients with bulimia nervosa (BN). Eight women diagnosed with BN according to Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision criteria participated in this study. We measured haemoglobin concentration changes in the DLPFC with near-infrared spectroscopy during cognitive tasks measuring self-regulatory control in response to food photo stimuli, both at baseline and after a single session of rTMS. Subjective ratings for food cravings demonstrated significant reduction. A significant decrease in cerebral oxygenation of the left DLPFC was also observed after a single session of rTMS. Measurement with NIRS after rTMS intervention may be applicable for discussing the mechanisms underlying rTMS modulation in patients with BN.

  7. Advanced cerebral monitoring in neurocritical care

    Directory of Open Access Journals (Sweden)

    Barazangi Nobl

    2008-01-01

    Full Text Available New cerebral monitoring techniques allow direct measurement of brain oxygenation and metabolism. Investigation using these new tools has provided additional insight into the understanding of the pathophysiology of acute brain injury and suggested new ways to guide management of secondary brain injury. Studies of focal brain tissue oxygen monitoring have suggested ischemic thresholds in focal regions of brain injury and demonstrated the interrelationship between brain tissue oxygen tension (P bt O 2 and other cerebral physiologic and metabolic parameters. Jugular venous oxygen saturation (SjVO 2 monitoring may evaluate global brain oxygen delivery and consumption, providing thresholds for detecting brain hypoperfusion and hyperperfusion. Furthermore, critically low values of P bt O 2 and SjVO 2 have also been predictive of mortality and worsened functional outcome, especially after head trauma. Cerebral microdialysis measures the concentrations of extracellular metabolites which may be relevant to cerebral metabolism or ischemia in focal areas of injury. Cerebral blood flow may be measured in the neurointensive care unit using continuous methods such as thermal diffusion and laser Doppler flowmetry. Initial studies have also attempted to correlate findings from advanced neuromonitoring with neuroimaging using dynamic perfusion computed tomography, positron emission tomography, and Xenon computed tomography. Additionally, new methods of data acquisition, storage, and analysis are being developed to address the increasing burden of patient data from neuromonitoring. Advanced informatics techniques such as hierarchical data clustering, generalized linear models, and heat map dendrograms are now being applied to multivariable patient data in order to better develop physiologic patient profiles to improve diagnosis and treatment.

  8. Arterial spin labeling perfusion MRI in cerebral ischaemia

    NARCIS (Netherlands)

    Bokkers, R.P.H.

    2011-01-01

    Cerebral perfusion is the basis for the delivery of oxygen and nutrients to the brain. Brain tissue can become damaged when there is a shortage in the blood supply. Basic physiological functions such as synaptic transmission, the membrane ion pump and energy metabolism are disrupted and within minut

  9. Dose-Dependent Hemodynamic, Biochemical, and Tissue Oxygen Effects of OC99 following Severe Oxygen Debt Produced by Hemorrhagic Shock in Dogs

    Directory of Open Access Journals (Sweden)

    William W. Muir

    2014-01-01

    Full Text Available We determined the dose-dependent effects of OC99, a novel, stabilized hemoglobin-based oxygen-carrier, on hemodynamics, systemic and pulmonary artery pressures, surrogates of tissue oxygen debt (arterial lactate 7.2±0.1 mM/L and arterial base excess −17.9 ± 0.5 mM/L, and tissue oxygen tension (tPO2 in a dog model of controlled severe oxygen-debt from hemorrhagic shock. The dose/rate for OC99 was established from a pilot study conducted in six bled dogs. Subsequently twenty-four dogs were randomly assigned to one of four groups (n=6 per group and administered: 0.0, 0.065, 0.325, or 0.65 g/kg of OC99 combined with 10 mL/kg lactated Ringers solution administered in conjunction with 20 mL/kg Hextend IV over 60 minutes. The administration of 0.325 g/kg and 0.65 g/kg OC99 produced plasma hemoglobin concentrations of 0.63±0.01 and 1.11±0.02 g/dL, respectively, improved systemic hemodynamics, enhanced tPO2, and restored lactate and base excess values compared to 0.0 and 0.065 g/kg OC99. The administration of 0.65 g/kg OC99 significantly elevated pulmonary artery pressure. Plasma hemoglobin concentrations of OC99 ranging from 0.3 to 1.1 g/dL, in conjunction with colloid based fluid resuscitation, normalized clinical surrogates of tissue oxygen debt, improved tPO2, and avoided clinically relevant increases in pulmonary artery pressure.

  10. Dose-Dependent Hemodynamic, Biochemical, and Tissue Oxygen Effects of OC99 following Severe Oxygen Debt Produced by Hemorrhagic Shock in Dogs.

    Science.gov (United States)

    Muir, William W; Del Rio, Carlos L; Ueyama, Yukie; Youngblood, Bradley L; George, Robert S; Rausch, Carl W; Lau, Billy S H; Hamlin, Robert L

    2014-01-01

    We determined the dose-dependent effects of OC99, a novel, stabilized hemoglobin-based oxygen-carrier, on hemodynamics, systemic and pulmonary artery pressures, surrogates of tissue oxygen debt (arterial lactate 7.2 ± 0.1 mM/L and arterial base excess -17.9 ± 0.5 mM/L), and tissue oxygen tension (tPO2) in a dog model of controlled severe oxygen-debt from hemorrhagic shock. The dose/rate for OC99 was established from a pilot study conducted in six bled dogs. Subsequently twenty-four dogs were randomly assigned to one of four groups (n = 6 per group) and administered: 0.0, 0.065, 0.325, or 0.65 g/kg of OC99 combined with 10 mL/kg lactated Ringers solution administered in conjunction with 20 mL/kg Hextend IV over 60 minutes. The administration of 0.325 g/kg and 0.65 g/kg OC99 produced plasma hemoglobin concentrations of 0.63 ± 0.01 and 1.11 ± 0.02 g/dL, respectively, improved systemic hemodynamics, enhanced tPO2, and restored lactate and base excess values compared to 0.0 and 0.065 g/kg OC99. The administration of 0.65 g/kg OC99 significantly elevated pulmonary artery pressure. Plasma hemoglobin concentrations of OC99 ranging from 0.3 to 1.1 g/dL, in conjunction with colloid based fluid resuscitation, normalized clinical surrogates of tissue oxygen debt, improved tPO2, and avoided clinically relevant increases in pulmonary artery pressure.

  11. Análise da respiração mitocondrial em tecido cerebral de gato após isquemia e reperfusão Analysis of mitochondrial respiration in brain cerebral tissue of cats after ischemia and reperfusion

    Directory of Open Access Journals (Sweden)

    Hiroshi Nakano

    2002-01-01

    perfomed aiming the better understanding of these phenomena. This study aimed to analyse the precocious effects of focal isquemia and reperfusion uppon the brain of cats. METHODS: Focal brain ischemia was performed by temporary clipping of the middle cerebral artery for determined times followed by reperfusion during 10 minutes. The effects of isquemia were assessed through mitochondrial respiration analysis in the ischemic tissue. RESULTS: The results showed a significant decrease in O2 consumption in samples of brain tissue submitted to 60 minutes of ischemia and 10 minutes of reperfusion when compared with not ischemic brain tissue, indicating compromising of the mitocondrial function. CONCLUSION: Based on the results we can conclude that time of ischemia was a determinant factor in the mitochondrial respiration alterations in brain tissue of cats submitted to ischemia and reperfusion of short duration (significant alterations observed only after 60 minutes of ischemia followed by 10 minutes of reperfusion.

  12. Cerebral Paragonimiasis.

    Science.gov (United States)

    Miyazaki, I

    1975-01-01

    The first case of cerebral paragonimiasis was reported by Otani in Japan in 1887. This was nine years after Kerbert's discovery of the fluke in the lungs of Bengal tigers and seven years after a human pulmonary infection by the fluke was demonstrated by Baelz and Manson. The first case was a 26-year-old man who had been suffering from cough and hemosputum for one year. The patient developed convulsive seizures with subsequent coma and died. The postmortem examination showed cystic lesions in the right frontal and occipital lobes. An adult fluke was found in the occipital lesion and another was seen in a gross specimen of normal brain tissue around the affected occipital lobe. Two years after Otani's discovery, at autopsy a 29-year-old man with a history of Jacksonian seizure was reported as having cerebral paragonimiasis. Some time later, however, it was confirmed that the case was actually cerebral schistosomiasis japonica. Subsequently, cases of cerebral paragonimiasis were reported. However, the majority of these cases were not confirmed histologically. It was pointed out that some of these early cases were probably not Paragonimus infection. After World War II, reviews as well as case reports were published. Recently, investigations have been reported from Korea, with a clinicla study on 62 cases of cerebral paragonimiasis seen at the Neurology Department of the National Medical Center, Seoul, between 1958 and 1964. In 1971 Higashi described a statistical study on 105 cases of cerebral paragonimiasis that had been treated surgically in Japan.

  13. NIRS-Derived Tissue Oxygen Saturation and Hydrogen Ion Concentration Following Bed Rest

    Science.gov (United States)

    Lee, S. M. C.; Everett, M. E.; Crowell, J. B.; Westby, C. M.; Soller, B. R.

    2010-01-01

    Long-term bed rest (BR), a model of spaceflight, results in a decrease in aerobic capacity and altered submaximal exercise responses. The strongest BR-induced effects on exercise appear to be centrally-mediated, but longer BR durations may result in peripheral adaptations (e.g., decreased mitochondrial and capillary density) which are likely to influence exercise responses. PURPOSE: To measure tissue oxygen saturation (SO2) and hydrogen ion concentration ([H+]) in the vastus lateralis (VL) using near infrared spectroscopy (NIRS) during cycle ergometry before and after . 30 d of BR. METHODS: Eight subjects performed a graded exercise test on a cycle ergometer to volitional fatigue 7 d before (pre-BR) and at the end or 1 day after BR (post-BR). NIRS spectra were collected from a sensor adhered to the skin overlying the VL. Oxygen consumption (VO2) was measured by open circuit spirometry. Blood volume (BV) was measured before and after BR using the carbon monoxide rebreathing technique. Changes in pre- and post-BR SO2 and [H+] data were compared using mixed model analyses. BV and peak exercise data were compared using paired t-tests. RESULTS: BV (pre-BR: 4.3+/-0.3, post-BR: 3.7+/-0.2 L, mean+/-SE, p=.01) and peak VO2 (pre-BR: 1.98+/-0.24, post-BR: 1.48 +/-0.21 L/min, padaptations which contribute to cardiovascular and muscular deconditioning as measured by NIRS-derived SO2 and [H+] in the VL and may contribute to lower post-BR exercise tolerance. Supported by the National Space Biomedical Research Institute through NASA NCC 9-58

  14. Influence of acetyl-carnitine on some mitochondrial enzymic activities in the human cerebral tissue in conditions of acute hypoxia.

    Science.gov (United States)

    Corbucci, G G; Melis, A; Piga, M; Marchionni, A; Calvani, M

    1992-01-01

    Following previous research on human tissue in conditions of acute and massive hypoxia, in the present work the authors compared the cellular enzymic response to oxidative stress in normoxic (perifocal) and hypoxic (focal) areas in human brain affected by regional acute vasculopathies. Two homogeneous groups of patients were selected following strict clinical inclusion/exclusion criteria. The groups of patients were treated with a placebo or acetyl-carnitine at same doses and following randomized, double-blind procedures. The focal areas showed a significant functional damage in lactate, pyruvate and succinate dehydrogenases and in the cytochrome oxidase activity when compared with the enzymic capacities of perifocal areas (normoxic as controls). The pretreatment with acetyl-carnitine antagonized the above-mentioned enzymic damage by a protective action linked to the endocellular energy restoration. In accordance with these data, the therapeutic role played by acetyl-carnitine in the cerebral focal hypoxia appeared to be a determinant for the cell survival mainly in the reversible phase of oxidative damage.

  15. Dual role of cerebral blood flow in regional brain temperature control in the healthy newborn infant.

    Science.gov (United States)

    Iwata, Sachiko; Tachtsidis, Ilias; Takashima, Sachio; Matsuishi, Toyojiro; Robertson, Nicola J; Iwata, Osuke

    2014-10-01

    Small shifts in brain temperature after hypoxia-ischaemia affect cell viability. The main determinants of brain temperature are cerebral metabolism, which contributes to local heat production, and brain perfusion, which removes heat. However, few studies have addressed the effect of cerebral metabolism and perfusion on regional brain temperature in human neonates because of the lack of non-invasive cot-side monitors. This study aimed (i) to determine non-invasive monitoring tools of cerebral metabolism and perfusion by combining near-infrared spectroscopy and echocardiography, and (ii) to investigate the dependence of brain temperature on cerebral metabolism and perfusion in unsedated newborn infants. Thirty-two healthy newborn infants were recruited. They were studied with cerebral near-infrared spectroscopy, echocardiography, and a zero-heat flux tissue thermometer. A surrogate of cerebral blood flow (CBF) was measured using superior vena cava flow adjusted for cerebral volume (rSVC flow). The tissue oxygenation index, fractional oxygen extraction (FOE), and the cerebral metabolic rate of oxygen relative to rSVC flow (CMRO₂ index) were also estimated. A greater rSVC flow was positively associated with higher brain temperatures, particularly for superficial structures. The CMRO₂ index and rSVC flow were positively coupled. However, brain temperature was independent of FOE and the CMRO₂ index. A cooler ambient temperature was associated with a greater temperature gradient between the scalp surface and the body core. Cerebral oxygen metabolism and perfusion were monitored in newborn infants without using tracers. In these healthy newborn infants, cerebral perfusion and ambient temperature were significant independent variables of brain temperature. CBF has primarily been associated with heat removal from the brain. However, our results suggest that CBF is likely to deliver heat specifically to the superficial brain. Further studies are required to assess the

  16. Dehydration affects cerebral blood flow but not its metabolic rate for oxygen during maximal exercise in trained humans

    DEFF Research Database (Denmark)

    Trangmar, Steven J; Chiesa, Scott T; Stock, Christopher G

    2014-01-01

    venous noradrenaline, and falling arterial carbon dioxide tension (P aCO 2) (R(2) ≥ 0.41, P ≤ 0.01) whereas CCA flow and conductance were related to elevated blood temperature. In conclusion, dehydration accelerated the decline in CBF by decreasing P aCO 2 and enhancing vasoconstrictor activity. However......Intense exercise is associated with a reduction in cerebral blood flow (CBF), but regulation of CBF during strenuous exercise in the heat with dehydration is unclear. We assessed internal (ICA) and common carotid artery (CCA) haemodynamics (indicative of CBF and extra-cranial blood flow), middle...... cerebral artery velocity (MCA Vmean), arterial-venous differences and blood temperature in 10 trained males during incremental cycling to exhaustion in the heat (35°C) in control, dehydrated and rehydrated states. Dehydration reduced body mass (75.8 ± 3 vs. 78.2 ± 3 kg), increased internal temperature (38...

  17. Cerebral Metabolic Profiling of Hypothermic Circulatory Arrest with and Without Antegrade Selective Cerebral Perfusion: Evidence from Nontargeted Tissue Metabolomics in a Rabbit Model

    Institute of Scientific and Technical Information of China (English)

    Li-Hua Zou; Jin-Ping Liu; Hao Zhang; Shu-Bin Wu; Bing-Yang Ji

    2016-01-01

    Background:Antegrade selective cerebral perfusion (ASCP) is regarded to perform cerebral protection during the thoracic aorta surgery as an adjunctive technique to deep hypothermic circulatory arrest (DHCA).However,brain metabolism profile after ASCP has not been systematically investigated by metabolomics technology.Methods:To clarify the metabolomics profiling of ASCP,12 New Zealand white rabbits were randomly assigned into 60 min DHCA with (DHCA+ASCP [DA] group,n =6) and without (DHCA [D] group,n =6) ASCP according to the random number table.ASCP was conducted by cannulation on the right subclavian artery and cross-clamping of the innominate artery.Rabbits were sacrificed 60 min after weaning off cardiopulmonary bypass.The metabolic features of the cerebral cortex were analyzed by a nontargeted metabolic profiling strategy based on gas chromatography-mass spectrometry.Variable importance projection values exceeding 1.0 were selected as potentially changed metabolites,and then Student's t-test was applied to test for statistical significance between the two groups.Results:Metabolic profiling of brain was distinctive significantly between the two groups (Q2y =0.88 for partial least squares-DA model).In comparing to group D,62 definable metabolites were varied significantly after ASCP,which were mainly related to amino acid metabolism,carbohydrate metabolism,and lipid metabolism.Kyoto Encyclopedia of Genes and Genomes analysis revealed that metabolic pathways after DHCA with ASCP were mainly involved in the activated glycolytic pathway,subdued anaerobic metabolism,and oxidative stress.In addition,L-kynurenine (P =0.0019),5-methoxyindole-3-acetic acid (P =0.0499),and 5-hydroxyindole-3-acetic acid (P =0.0495) in tryptophan metabolism pathways were decreased,and citrulline (P =0.0158) in urea cycle was increased in group DA comparing to group D.Conclusions:The present study applied metabolomics analysis to identify the cerebral metabolic profiling in rabbits with ASCP

  18. Characterization of positron emission tomography hypoxia tracer uptake and tissue oxygenation via electrochemical modeling

    Energy Technology Data Exchange (ETDEWEB)

    Bowen, Stephen R., E-mail: srbowen@wisc.edu [University of Wisconsin School of Medicine and Public Health, Department of Medical Physics, Madison, WI 53706 (United States); Kogel, Albert J. van der [University Medical Centre St. Radboud, Nijmegen (Netherlands); Nordsmark, Marianne [Aarhus University Hospital, Department of Experimental Clinical Oncology, Aarhus (Denmark); Bentzen, Soren M. [University of Wisconsin School of Medicine and Public Health, Department of Medical Physics, Madison, WI 53706 (United States); University of Wisconsin School of Medicine and Public Health, Department of Human Oncology, Clinical Sciences Center, Madison, WI 53792 (United States); Jeraj, Robert [University of Wisconsin School of Medicine and Public Health, Department of Medical Physics, Madison, WI 53706 (United States); University of Wisconsin School of Medicine and Public Health, Department of Human Oncology, Clinical Sciences Center, Madison, WI 53792 (United States); Jozef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia)

    2011-08-15

    Purpose: Unique uptake and retention mechanisms of positron emission tomography (PET) hypoxia tracers make in vivo comparison between them challenging. Differences in imaged uptake of two common hypoxia radiotracers, [{sup 61}Cu]Cu-ATSM and [{sup 18}F]FMISO, were characterized via computational modeling to address these challenges. Materials and Methods: An electrochemical formalism describing bioreductive retention mechanisms of these tracers under steady-state conditions was adopted to relate time-averaged activity concentration to tissue partial oxygen tension (PO{sub 2}), a common metric of hypoxia. Chemical equilibrium constants of product concentration to reactant concentration ratios were determined from free energy changes and reduction potentials of pertinent reactions reported in the literature. Resulting transformation functions between tracer uptake and PO{sub 2} were compared against measured values in preclinical models. Additionally, calculated PO{sub 2} distributions from imaged Cu-ATSM tracer activity concentrations of 12 head and neck squamous cell carcinoma (HNSCC) patients were validated against microelectrode PO{sub 2} measurements in 69 HNSCC patients. Results: Both Cu-ASTM- and FMISO-modeled PO{sub 2} transformation functions were in agreement with preclinical measured values within single-deviation confidence intervals. High correlation (r{sup 2}=0.94, P<.05) was achieved between modeled PO{sub 2} distributions and measured distributions in the patient populations. On average, microelectrode hypoxia thresholds (2.5 and 5.0 mmHg) corresponded to higher Cu-ATSM uptake [2.5 and 2.0 standardized uptake value (SUV)] and lower FMISO uptake (2.0 and 1.4 SUV). Uncertainties in the models were dominated by variations in the estimated specific activity and intracellular acidity. Conclusions: Results indicated that the high dynamic range of Cu-ATSM uptake was representative of a narrow range of low oxygen tension whose values were dependent on

  19. Electroacupuncture at the Renzhong (DU 26) and Neiguan (PC 6) acupoints repairs the DNA of nervous tissue supplied by the middle cerebral artery in rats

    Institute of Scientific and Technical Information of China (English)

    Xiaorong Chang; Mi Liu; Jie Yan; Ling Fan; Wenjin Li; Chao Wang; Jianqiao Fang

    2011-01-01

    This study compares the changes of DNA repair in brain tissue dominated by the middle cerebral artery after electroacupuncture at the acupoints of Renzhong (DU 26), Neiguan (PC 6), Quchi (LI 11) and Zusanli (ST 36) in rats. In the apurinic/apyrimidinic endonuclease DNA basic group reparative excision experiments, the apurinic/apyrimidinic endonuclease activity of brain tissue increased slightly after electroacupuncture in rats. In the DNA polymerase β (Pol β)experiments, the Pol β activity of brain tissue increased after electroacupuncture, especially at DU 26 and PC 6. In the DNA ligase experiments, the expression of DNA ligase 1 in brain tissue increased significantly after electroacupuncture. These findings demonstrate increased activity of apurinic/apyrimidinic endonuclease, Pol β and DNA ligase 1 after electroacupuncture at DU 26 and PC 6. Also, DNA repair in brain tissue supplied by the middle cerebral artery is promoted after electroacupuncture at DU 26 and PC 6, which are more effective than the LI 11 and ST 36 acupoints

  20. Substrate stiffness and oxygen as regulators of stem cell differentiation during skeletal tissue regeneration: a mechanobiological model.

    Directory of Open Access Journals (Sweden)

    Darren Paul Burke

    Full Text Available Extrinsic mechanical signals have been implicated as key regulators of mesenchymal stem cell (MSC differentiation. It has been possible to test different hypotheses for mechano-regulated MSC differentiation by attempting to simulate regenerative events such as bone fracture repair, where repeatable spatial and temporal patterns of tissue differentiation occur. More recently, in vitro studies have identified other environmental cues such as substrate stiffness and oxygen tension as key regulators of MSC differentiation; however it remains unclear if and how such cues determine stem cell fate in vivo. As part of this study, a computational model was developed to test the hypothesis that substrate stiffness and oxygen tension regulate stem cell differentiation during fracture healing. Rather than assuming mechanical signals act directly on stem cells to determine their differentiation pathway, it is postulated that they act indirectly to regulate angiogenesis and hence partially determine the local oxygen environment within a regenerating tissue. Chondrogenesis of MSCs was hypothesized to occur in low oxygen regions, while in well vascularised regions of the regenerating tissue a soft local substrate was hypothesised to facilitate adipogenesis while a stiff substrate facilitated osteogenesis. Predictions from the model were compared to both experimental data and to predictions of a well established computational mechanobiological model where tissue differentiation is assumed to be regulated directly by the local mechanical environment. The model predicted all the major events of fracture repair, including cartilaginous bridging, endosteal and periosteal bony bridging and bone remodelling. It therefore provides support for the hypothesis that substrate stiffness and oxygen play a key role in regulating MSC fate during regenerative events such as fracture healing.

  1. Near-infrared spectroscopy assessed cerebral oxygenation during open abdominal aortic aneurysm repair: relation to end-tidal CO2 tension.

    Science.gov (United States)

    Sørensen, H; Nielsen, H B; Secher, N H

    2016-08-01

    During open abdominal aortic aneurism (AAA) repair cerebral blood flow is challenged. Clamping of the aorta may lead to unintended hyperventilation as metabolism is reduced by perfusion of a smaller part of the body and reperfusion of the aorta releases vasodilatory substances including CO2. We intend to adjust ventilation according end-tidal CO2 tension (EtCO2) and here evaluated to what extent that strategy maintains frontal lobe oxygenation (ScO2) as determined by near infrared spectroscopy. For 44 patients [5 women, aged 70 (48-83) years] ScO2, mean arterial pressure (MAP), EtCO2, and ventilation were obtained retrospectively from the anesthetic charts. By clamping the aorta, ScO2 and EtCO2 were kept stable by reducing ventilation (median, -0.8 l min(-1); interquartile range, -1.1 to -0.4; P body is reperfused.

  2. The significance of changes in cerebral oxygen and glucose metabolism in patients with cerebral hemorrhage caused by acute hypertension%急性高血压脑出血患者脑糖氧代谢变化及意义

    Institute of Scientific and Technical Information of China (English)

    马骏; 陈锷峰; 屠传建; 钱辉; 骆明; 顾志伟; 张建民

    2014-01-01

    Objective To study the clinical significance of early changes in cerebral oxygen and glucose metabolism in patients with cerebral hemorrhage and with Glasgow coma score (GCS) of 5-8 caused by acute hypertension in order to find relationship between those changes and prognosis.Methods From January 1,2011 to June 30,2012,a cohort of 43 patients with cerebral hemorrhage caused by acute hypertension were enrolled for retrospective study.Radial artery and internal jugular vein were separately cannulated retrogradely for collecting blood for blood gas analysis and blood glucose tests carried out 24 hours after the onset of the cerebral hemorrhage and then every 6-8 hours and as any major changes in physical signs of patients occurred.And this monitoring kept for consecutive 3 days.The data of these laboratory findings were analyzed and calculated to determine internal jugular vein oxygen saturation (SjVO2),cerebral oxygen utilization rate (CEO2),cerebral arterio-venous oxygen difference (AVDO2),arterio-venous blood glucose difference (V-Aglu),arterio-venous lactic acid difference (V-Alac) and absolute value of carbon dioxide pressure difference between jugular vein and artery (V-APCO2).All patients met the diagnostic criteria of hypertensive cerebral hemorrhage revised by the 4th National Academic Conference on cerebrovascular disease in 1995 requiring diagnosis confirmed by brain CT,admitted within 24 hours of onset,Glasgow coma score (GCS) 5-8 and a history of hypertension.Exclusion criteria were:cerebral hemorrhage caused by traumatic intracranial hematoma,spontaneous subarachnoid hemorrhage,arteriovenous malformation and Moyamoya disease,intracranial tumor apoplexy,cerebral bleeding derived from the disturbance of blood coagulation system,and cerebral hemorrhagic infarction.According to the short-term prognosis,the patients were divided into the death group and the survival group.Then the differences in biomarkers mentioned above between two groups were compared to

  3. Expression of the urokinase plasminogen activator receptor (uPAR) and its ligand (uPA) in brain tissues of human immunodeficiency virus patients with opportunistic cerebral diseases.

    Science.gov (United States)

    Nebuloni, Manuela; Cinque, Paola; Sidenius, Nicolai; Ferri, Angelita; Lauri, Eleonora; Omodeo-Zorini, Elisabetta; Zerbi, Pietro; Vago, Luca

    2009-01-01

    The urokinase plasminogen activator receptor (uPAR) and its ligand (uPA) play an important role in cell migration and extracellular proteolysis. We previously described uPAR/uPA overexpression in the cerebrospinal fluid (CSF) and brain tissues of patients with human immunodeficiency virus (HIV)-related cerebral diseases. In this study, we examined uPAR/uPA expression by immunohistochemistry (IHC) in brains of HIV patients with opportunistic cerebral lesions and in HIV-positive/negative controls. uPAR was found in macrophages/microglia with the highest levels in cytomegalovirus (CMV) encephalitis, toxoplasmosis, and lymphomas; in cryptococcosis and progressive multifocal leukoencephalopathy (PML) cases, only a few positive cells were found and no positivity was observed in controls. uPA expression was demonstrated only in a few macrophages/microglia and lymphocytes in all the cases and HIV-positive controls without different pattern of distribution; no uPA immunostaining was found in cryptococcosis and HIV-negative controls. The higher expression of uPAR/uPA in most of the opportunistic cerebral lesions supports their role in these diseases, suggesting their contribution to tissue injury.

  4. Cerebral oximetry and cerebral blood flow monitoring in 2 pediatric survivors with out-of-hospital cardiac arrest.

    Science.gov (United States)

    Abramo, Thomas; Aggarwal, Nitin; Kane, Ian; Crossman, Kristen; Meredith, Mark

    2014-04-01

    In pediatric out-of-hospital cardiac arrest (POHCA), cardiovascular monitoring tools have improved resuscitative endeavors and cardiovascular outcomes but with still poor neurologic outcomes. Regarding cardiac arrest in patients with congenital heart disease during surgery, the application of cerebral oximetry with blood volume index (BVI) during the resuscitation has shown significant results and prognostic significance. We present 2 POHCA patients who had cerebral oximetry with BVI monitoring during their arrest and postarrest phase in the emergency department and its potential prognostic aspect.Basic procedures include left and right cerebral oximetry with BVI monitoring at every 5-second interval during cardiac arrest, resuscitation, and postarrest in 2 POHCA patients in the pediatric emergency department.Regional cerebral tissue oxygen saturation (rSo2) with BVI readings in these 2 POHCA survivors demonstrated interesting cerebral physiology, blood flow, and potential prognostic outcome. In 1 patient, the reference range of cerebral rSo2 with positive blood flow during arrest and postarrest phases consistently occurred. This neurologic monitoring had its significance when the resuscitation effectiveness was used and end-tidal CO2 changes were lost. The other patient's cerebral rSo2 with simultaneous BVI readings and trending showed the effectiveness of the emergency medical services (EMS) resuscitation.Cerebral oximetry with cerebral blood flow index monitoring in these POHCA survivors demonstrates compelling periarrest and postarrest cerebral physiology information and prognostication. Cerebral oximetry with cerebral BVI monitoring during these arrest phases has potential as a neurologic monitor for the resuscitative intervention's effectiveness and its possible neurologic prognostic application in the pediatric OCHA patients.

  5. Effects of Neural Stem Cell and Olfactory Ensheathing Cell Co-transplants on Tissue Remodelling After Transient Focal Cerebral Ischemia in the Adult Rat.

    Science.gov (United States)

    Augestad, Ingrid Lovise; Nyman, Axel Karl Gottfrid; Costa, Alex Ignatius; Barnett, Susan Carol; Sandvig, Axel; Håberg, Asta Kristine; Sandvig, Ioanna

    2017-01-24

    Effective transplant-mediated repair of ischemic brain lesions entails extensive tissue remodeling, especially in the ischemic core. Neural stem cells (NSCs) are promising reparative candidates for stroke induced lesions, however, their survival and integration with the host-tissue post-transplantation is poor. In this study, we address this challenge by testing whether co-grafting of NSCs with olfactory ensheathing cells (OECs), a special type of glia with proven neuroprotective, immunomodulatory, and angiogenic effects, can promote graft survival and host tissue remodelling. Transient focal cerebral ischemia was induced in adult rats by a 60-min middle cerebral artery occlusion (MCAo) followed by reperfusion. Ischemic lesions were verified by neurological testing and magnetic resonance imaging. Transplantation into the globus pallidus of NSCs alone or in combination with OECs was performed at two weeks post-MCAo, followed by histological analyses at three weeks post-transplantation. We found evidence of extensive vascular remodelling in the ischemic core as well as evidence of NSC motility away from the graft and into the infarct border in severely lesioned animals co-grafted with OECs. These findings support a possible role of OECs as part of an in situ tissue engineering paradigm for transplant mediated repair of ischemic brain lesions.

  6. Tempol, an intracellular antioxidant, inhibits tissue factor expression, attenuates dendritic cell function, and is partially protective in a murine model of cerebral malaria.

    Directory of Open Access Journals (Sweden)

    Ivo M B Francischetti

    Full Text Available BACKGROUND: The role of intracellular radical oxygen species (ROS in pathogenesis of cerebral malaria (CM remains incompletely understood. METHODS AND FINDINGS: We undertook testing Tempol--a superoxide dismutase (SOD mimetic and pleiotropic intracellular antioxidant--in cells relevant to malaria pathogenesis in the context of coagulation and inflammation. Tempol was also tested in a murine model of CM induced by Plasmodium berghei Anka infection. Tempol was found to prevent transcription and functional expression of procoagulant tissue factor in endothelial cells (ECs stimulated by lipopolysaccharide (LPS. This effect was accompanied by inhibition of IL-6, IL-8, and monocyte chemoattractant protein (MCP-1 production. Tempol also attenuated platelet aggregation and human promyelocytic leukemia HL60 cells oxidative burst. In dendritic cells, Tempol inhibited LPS-induced production of TNF-α, IL-6, and IL-12p70, downregulated expression of co-stimulatory molecules, and prevented antigen-dependent lymphocyte proliferation. Notably, Tempol (20 mg/kg partially increased the survival of mice with CM. Mechanistically, treated mice had lowered plasma levels of MCP-1, suggesting that Tempol downmodulates EC function and vascular inflammation. Tempol also diminished blood brain barrier permeability associated with CM when started at day 4 post infection but not at day 1, suggesting that ROS production is tightly regulated. Other antioxidants-such as α-phenyl N-tertiary-butyl nitrone (PBN; a spin trap, MnTe-2-PyP and MnTBAP (Mn-phorphyrin, Mitoquinone (MitoQ and Mitotempo (mitochondrial antioxidants, M30 (an iron chelator, and epigallocatechin gallate (EGCG; polyphenol from green tea did not improve survival. By contrast, these compounds (except PBN inhibited Plasmodium falciparum growth in culture with different IC50s. Knockout mice for SOD1 or phagocyte nicotinamide adenine dinucleotide phosphate (NADPH oxidase (gp91(phox-/- or mice treated with

  7. Downstream signaling of reactive oxygen species, protein kinase C epsilon translocation and delayed neuroprotection in sevoflurane preconditioned rats following cerebral ischemia/reperfusion

    Institute of Scientific and Technical Information of China (English)

    Zhi Ye; Qulian Guo; E Wang; Yundan Pan; Qing Li; Honghao Zhou

    2009-01-01

    BACKGROUND: Brief exposure to the anesthetic sevoflurane results in delayed neuroprotection.However, few studies have addressed delayed neuroprotection after preconditioning with a single administration of sevoflurane.OBJECTIVE: To explore the relationship between a single preconditioning administration of sevoflurane and reactive oxygen species production and protein kinase C-epsilon (PKC- ε ) translocation.DESIGN, TIME, AND SETTING: The randomized, controlled, animal experiment was conducted at the Central Laboratory, Xiangya Hospital, Central South University, China from November 2007 to April 2008.MATERIALS: A total of 120 healthy, male, Sprague Dawley rats were equally and randomly assigned into five groups: sham operation, ischemia/reperfusion, sevoflurane, 2-mercaptopropionylglycine (2-MPG, a selective reactive oxygen species scavenger) + sevoflurane (MPG + sevoflurane), and MPG. Sevoflurane (Baxter, USA) and MPG (Sigma, USA) were used in this study.METHODS: Intervention consisted of three procedures. (1) MPG injection: a selective reactive oxygen species scavenger, MPG (20 mg/kg), was infused into the rat caudal vein in the MPG and MPG + sevoflurane groups. (2) Sevoflurane preconditioning: 30 minutes following MPG injection,rats in the sevoflurane and MPG + sevoflurane groups breathed a mixed gas of 2.4% sevoflurane and 97.6% oxygen for 60 minutes. Rats in the sham operation, ischemia/reperfusion, and MPG groups breathed 100% pure oxygen for 60 minutes. (3) Ischemia/reperfusion: 24 hours after sevoflurane or pure oxygen preconditioning, middle cerebral artery occlusion models were established in the ischemia/reperfusion, sevoflurane, MPG + sevoflurane, and MPG groups.Following 2 hours ischemia/6 hours and 24 hours reperfusion, the carotid artery was separated, but the middle cerebral artery was not occluded, in the sham operation group.MAIN OUTCOME MEASURES: In the ischemic hemisphere, PKC-ε translocation in the rat parietal cortex was measured by Western

  8. Cerebral microcirculation during experimental normovolaemic anaemia

    Directory of Open Access Journals (Sweden)

    Judith eBellapart

    2016-02-01

    Full Text Available Anaemia is accepted amongst critically ill patients as an alternative to elective blood transfusion. This practice has been extrapolated to head injury patients with only one study comparing the effects of mild anaemia on neurological outcome. There are no studies quantifying microcirculation during anaemia. Experimental studies suggest that anaemia leads to cerebral hypoxia and increased rates of infarction, but the lack of clinical equipoise when testing the cerebral effects of transfusion amongst critically injured patients, supports the need of experimental studies. The aim of this study was to quantify cerebral microcirculation and the potential presence of axonal damage in an experimental model exposed to normovolaemic anaemia, with the intention of describing possible limitations within management practices in critically ill patients. Under non-recovered anaesthesia, six Merino sheep were instrumented using an intracardiac transeptal catheter to inject coded microspheres into the left atrium to ensure systemic and non-chaotic distribution. Cytometric analyses quantified cerebral microcirculation at specific regions of the brain. Amyloid precursor protein staining was used as an indicator of axonal damage. Animals were exposed to normovolaemic anaemia by blood extractions from the indwelling arterial catheter with simultaneous fluid replacement through a venous central catheter. Simultaneous data recording from cerebral tissue oxygenation, intracranial pressure and cardiac output was monitored. A regression model was used to examine the effects of anaemia on microcirculation with a mixed model to control for repeated measures. Homogeneous and normal cerebral microcirculation with no evidence of axonal damage was present in all cerebral regions, with no temporal variability, concluding that acute normovolaemic anaemia does not result in short term effects on cerebral microcirculation in the ovine brain.

  9. Bilobalide inhibits the expression of aquaporin 1, 4 and glial fibrillary acidic protein in rat brain tissue after permanent focal cerebral ischemia

    Institute of Scientific and Technical Information of China (English)

    Haiming Qin; Fulin Song; Hongguang Han; Hong Qu; Xingwen Zhai; Bin Qin; Song You

    2011-01-01

    The present results demonstrated that in an adult rat model of permanent middle cerebral artery occlusion (pMCAO), pretreatment with bilobalide reduced brain water content and infarct area, down-regulated aquaporin 1, 4 mRNA expression in brain edema tissue, then inhibited their synthesis in the striatum, in particular at the early stage of ischemia (at 8 hours after pMCAO), inhibited glial fibrillary acidic protein expression, and lightened reactive gliosis. These data sug-gest that bilobalide attenuates brain edema formation due to reduced expression of aquaporins.

  10. Blood-Oxygenation-Level-Dependent-(BOLD- Based R2′ MRI Study in Monkey Model of Reversible Middle Cerebral Artery Occlusion

    Directory of Open Access Journals (Sweden)

    Jing Zhang

    2011-01-01

    Full Text Available Objective. To investigate the value of BOLD-based reversible transverse relaxation rate (R2′ MRI in detecting ischemic penumbra (IP in a monkey model of reversible middle cerebral artery occlusion (MCAO and time evolution of relative R2′ (rR2′ in infarcted core, IP, and oligemia. Materials and Methods. 6 monkeys were used to make MCAO by the microcatheter method. MR scans were performed at 0 h (1 h after MCAO, 1 h, 3 h, 6 h, 12 h, 24 h, and 48 h after reperfusion. R2′ was calculated using quantitative T2 and T2∗ maps. Ischemic area was subdivided into infracted core, IP and oligemia. rR2′ was calculated respectively. Results. Reversible MCAO model for 4/6 monkeys was made successfully. rR2′ values were significantly different at each time point, being highest in oligemia followed by IP and infarcted core (<.05. With reperfusion time evolution, rR2′ in infarcted core showed a decreased trend: sharply decreased within 6 hours and maintained at 0 during 6–48 hours (<.05. rR2′ values in IP and oligemia showed similar increased trend: sharply increased within 6 hours, maintained a plateau during 6–24 hours, and slightly increased until 48 hours. Conclusion. BOLD-based R2′ MRI can be used to describe changes of cerebral oxygen extract in acute ischemic stroke, and it can provide additional information in detecting IP. The time evolution rR2′ in infarcted core, IP, and oligemia is in accordance with the underlying pathophysiology.

  11. Changes in serum cellular adhesion molecule and matrix metalloproteinase-9 levels in patients with cerebral infarction following hyperbaric oxygen therapy A case and intergroup control study

    Institute of Scientific and Technical Information of China (English)

    Renliang Zhao; Chunxia Wang; Yongjun Wang

    2008-01-01

    BACKGROUND: Animal studies have confirmed that hyperbaric oxygen (HBO) therapy can reduce matrix metalloproteinase activity and blood brain barrier permeability, thereby exhibiting neuroprotective effects. However, at present, consensus does not exist in terms of its clinical efficacy. OBJECTIVE: To validate the significance of changes in serum cellular adhesion molecule and MMP-9 levels in patients with cerebral infarction following HBO therapy. DESIGN, TIME AND SETTING: This randomized, controlled, neurobiochemical study was performed at the Department of Neurology, Affiliated Hospital of Qingdao University Medical College between December 2002 and March 2006. PARTICIPANTS: A total of 112 patients with acute cerebral infarction of internal carotid artery, comprising 64 males and 48 females, averaging (67 ± 11) years, were recruited and randomized to a HBO group (n = 50) and a routine treatment group (n = 62). An additional 30 gender- and age-matched normal subjects, consisting of 17 males and 13 females, averaging (63 ± 9) years, were enrolled as control subjects. METHODS: The routine treatment group received routine drug treatment and rehabilitation exercise. HBO treatment was additionally performed in the HBO group, once a day, for a total of 10 days. MAIN OUTCOME MEASURES: Serum levels of soluble intercellular adhesion molecule, soluble vascular cell adhesion molecule, soluble E-selectin, and matrix metalloproteinase-9 were detected by enzyme linked immunosorbent assay. RESULTS: Upon admission, serum levels of soluble intercellular adhesion molecule, soluble vascular cell adhesion molecule, soluble E-selectin, and matrix metalloproteinase-9 were significantly increased in patients with cerebral infarction, compared with control subjects (P < 0.01). Following HBO and routine treatments, serum levels of the above-mentioned indices were significantly reduced in the HBO and routine treatment groups (P < 0.01). Moreover, greater efficacy was observed in the HBO

  12. An upgraded camera-based imaging system for mapping venous blood oxygenation in human skin tissue

    Science.gov (United States)

    Li, Jun; Zhang, Xiao; Qiu, Lina; Leotta, Daniel F.

    2016-07-01

    A camera-based imaging system was previously developed for mapping venous blood oxygenation in human skin. However, several limitations were realized in later applications, which could lead to either significant bias in the estimated oxygen saturation value or poor spatial resolution in the map of the oxygen saturation. To overcome these issues, an upgraded system was developed using improved modeling and image processing algorithms. In the modeling, Monte Carlo (MC) simulation was used to verify the effectiveness of the ratio-to-ratio method for semi-infinite and two-layer skin models, and then the relationship between the venous oxygen saturation and the ratio-to-ratio was determined. The improved image processing algorithms included surface curvature correction and motion compensation. The curvature correction is necessary when the imaged skin surface is uneven. The motion compensation is critical for the imaging system because surface motion is inevitable when the venous volume alteration is induced by cuff inflation. In addition to the modeling and image processing algorithms in the upgraded system, a ring light guide was used to achieve perpendicular and uniform incidence of light. Cross-polarization detection was also adopted to suppress surface specular reflection. The upgraded system was applied to mapping of venous oxygen saturation in the palm, opisthenar and forearm of human subjects. The spatial resolution of the oxygenation map achieved is much better than that of the original system. In addition, the mean values of the venous oxygen saturation for the three locations were verified with a commercial near-infrared spectroscopy system and were consistent with previously published data.

  13. Deriving concentrations of oxygen and carbon in human tissues using single- and dual-energy CT for ion therapy applications

    Science.gov (United States)

    Landry, Guillaume; Parodi, Katia; Wildberger, Joachim E.; Verhaegen, Frank

    2013-08-01

    Dedicated methods of in-vivo verification of ion treatment based on the detection of secondary emitted radiation, such as positron-emission-tomography and prompt gamma detection require high accuracy in the assignment of the elemental composition. This especially concerns the content in carbon and oxygen, which are the most abundant elements of human tissue. The standard single-energy computed tomography (SECT) approach to carbon and oxygen concentration determination has been shown to introduce significant discrepancies in the carbon and oxygen content of tissues. We propose a dual-energy CT (DECT)-based approach for carbon and oxygen content assignment and investigate the accuracy gains of the method. SECT and DECT Hounsfield units (HU) were calculated using the stoichiometric calibration procedure for a comprehensive set of human tissues. Fit parameters for the stoichiometric calibration were obtained from phantom scans. Gaussian distributions with standard deviations equal to those derived from phantom scans were subsequently generated for each tissue for several values of the computed tomography dose index (CTDIvol). The assignment of %weight carbon and oxygen (%wC,%wO) was performed based on SECT and DECT. The SECT scheme employed a HU versus %wC,O approach while for DECT we explored a Zeff versus %wC,O approach and a (Zeff, ρe) space approach. The accuracy of each scheme was estimated by calculating the root mean square (RMS) error on %wC,O derived from the input Gaussian distribution of HU for each tissue and also for the noiseless case as a limiting case. The (Zeff, ρe) space approach was also compared to SECT by comparing RMS error for hydrogen and nitrogen (%wH,%wN). Systematic shifts were applied to the tissue HU distributions to assess the robustness of the method against systematic uncertainties in the stoichiometric calibration procedure. In the absence of noise the (Zeff, ρe) space approach showed more accurate %wC,O assignment (largest error of

  14. The early life history of tissue oxygenation in crustaceans: the strategy of the myodocopid ostracod Cylindroleberis mariae.

    Science.gov (United States)

    Corbari, Laure; Carbonel, Pierre; Massabuau, Jean-Charles

    2005-02-01

    We studied basic principles of respiratory physiology in Cylindroleberididae, Cylindroleberis mariae Baird 1850, which are millimetre-sized crustaceans (myodocop ostracod) having a fossil record dating back to about 425 millions years ago. Facing experimental changes of O2 partial pressures in the range 2-40 kPa (normoxia is 21 kPa), C. mariae lack any regulatory mechanism to adapt their ventilatory and circulatory activity. Thus, the oxygenation status of their internal milieu must follow, as a dependent variable, the ambient oxygenation. Freely behaving C. mariae exhibit a marked diurnal activity rhythm. They are actively swimming in the water column during night, where they inspire in normoxic-normocapnic water. They are resting in self-made nests during daytime, where they are rebreathing in a confined and hypoxic environment. By analogy to extensive previous literature data, we suggest that these changes of respiratory gas content, and the associated tissue gas status, participate to the shaping of their metabolic activity and behaviour. To conclude, as Cylindroleberididae are early crustaceans exhibiting a remarkable stasis since the Palaeozoic, present data illustrates how principles of tissue oxygenation strategy can cover an impressive time scale.

  15. Study on changes of partial pressure of brain tissue oxygen and brain temperature in acute phase of severe head injury during mild hypothermia therapy

    Institute of Scientific and Technical Information of China (English)

    朱岩湘; 姚杰; 卢尚坤; 章更生; 周关仁

    2003-01-01

    Objective: To study the changes of partial pressure of brain tissue oxygen (PbtO2) and brain temperature in acute phase of severe head injury during mild hypothermia therapy and the clinical significance.Methods: One hundred and sixteen patients with severe head injury were selected and divided into a mild hypothermia group (n=58), and a control group (n=58) according to odd and even numbers of hospitalization. While mild hypothermia therapy was performed PbtO2 and brain temperature were monitored for 1-7 days (mean=86 hours), simultaneously, the intracranial pressure, rectum temperature, cerebral perfusion pressure, PaO2 and PaCO2 were also monitored. The patients were followed up for 6 months and the prognosis was evaluated with GOS (Glasgow outcome scale).Results: The mean value of PbtO2 within 24 hour monitoring in the 116 patients was 13.7 mm Hg±4.94 mm Hg, lower than the normal value (16 mm Hg±40 mm Hg) The time of PbtO2 recovering to the normal value in the mild hypothermia group was shortened by 10±4.15 hours compared with the control group (P<0.05). The survival rate of the mild hypothermia group was 60.43%, higher than that of the control group (46.55%). After the recovery of the brain temperature, PbtO2 increased with the rise of the brain temperature. Conclusions: Mild hypothermia can improve the survival rate of severe head injury. The technique of monitoring PbtO2 and the brain temperature is safe and reliable, and has important clinical significance in judging disease condition and instructing clinical therapy.

  16. Perfluorocarbon-loaded lipid nanocapsules as oxygen sensors for tumor tissue pO₂ assessment.

    Science.gov (United States)

    Lemaire, L; Bastiat, G; Franconi, F; Lautram, N; Duong Thi Dan, T; Garcion, E; Saulnier, P; Benoit, J P

    2013-08-01

    The assessment of tumor oxygenation is a crucial factor in cancer therapy and may be carried out using fluorine MRI once fluorine probes have been distributed within the tumor. However, the deposit of those highly fluorinated compounds often jeopardizes anatomical image quality and requires emulsification of the probes. Due to the high density and the high lipophilicity of perfluorocarbons, nanoemulsion of these molecules usually requires high-energy processes. In the present work, we discuss the synthesis and the physico-chemical characterization of perfluorocarbon nanocapsules using a low-energy phase-inversion process. The nanocapsules were tested on a mouse tumor brain model to assess oxygenation.

  17. Correlation of a novel noninvasive tissue oxygen saturation monitor to serum central venous oxygen saturation in pediatric patients with postoperative congenital cyanotic heart disease.

    Science.gov (United States)

    Yadlapati, Ajay; Grogan, Tristan; Elashoff, David; Kelly, Robert B

    2013-03-01

    Using a novel noninvasive, visible-light optical diffusion oximeter (T-Stat VLS Tissue Oximeter; Spectros Corporation, Portola Valley, CA) to measure the tissue oxygen saturation (StO2) of the buccal mucosa, the correlation between StOz and central venous oxygen saturation (ScvO2) was examined in children with congenital cyanotic heart disease undergoing a cardiac surgical procedure. Paired StO2 and serum ScvO2 measurements were obtained postoperatively and statistically analyzed for agreement and association. Thirteen children (nine male) participated in the study (age range, 4 days to 18 months). Surgeries included Glenn shunt procedures, Norwood procedures, unifocalization procedures with Blalock-Taussig shunt placement, a Kawashima/ Glenn shunt procedure, a Blalock-Taussig shunt placement, and a modified Norwood procedure. A total of 45 paired StO2-ScvO2 measurements was obtained. Linear regression demonstrated a Pearson's correlation of .58 (95% confidence interval [CI], .35-.75; p < .0001). The regression slope coefficient estimate was .95 (95% CI, .54-1.36) with an interclass correlation coefficient of .48 (95% CI, .22-.68). Below a clinically relevant average ScvO2 value, a receiver operator characteristic analysis yielded an area under the curve of .78. Statistical methods to control for repeatedly measuring the same subjects produced similar results. This study shows a moderate relationship and agreement between StO2 and ScvO2 measurements in pediatric patients with a history of congenital cyanotic heart disease undergoing a cardiac surgical procedure. This real-time monitoring device can act as a valuable adjunct to standard noninvasive monitoring in which serum SyvO2 sampling currently assists in the diagnosis of low cardiac output after pediatric cardiac surgery.

  18. Analyzing Ph value, energy and phospholipid metabolism of various cerebral tumors and normal brain tissue with 31P magnetic resonance spectroscopy

    Institute of Scientific and Technical Information of China (English)

    Wei Tan; Guangyao Wu; Junmo Sun

    2006-01-01

    BACKGROUND: 31P magnetic resonance spectroscopy (31P MRS) can be used to non-injuredly and dynamicly detect various metabolites including phosphorus in organis and reflect changes of phospholipid metabolism and energy metabolism in tissue and pH value in cells.OBJECTIVE: To observe changes of pH value, phospholipid metabolism and energy metabolism of various cerebral tumors and normal brain tissue with 31P MRS.DESIGN: Semi-quantitative contrast observation.PARTICIPANTS: A total of 44 patients with cerebral tumor diagnosed with surgery operation were selected from the Department of Magnetic Resonance, Central South Hospital, Wuhan University from September 2004 to June 2006. All the subjects had complete 31P MRS data before steroid and operation. Among them,16 patients had glioma of grade Ⅱ-Ⅲ, 12 spongioblastoma and 16 meningioma. The mean age was (45±6)years. Another 36 subjects without focus on cerebral MRI were regarded as normal group, including 19 males and 18 females, and the mean age was (41±4) years. Included subjects were consent.METHODS: Eclipse1.5T MRS (Philips Company) was used to collect wave spectrum; jMRUI(1.3) was used to analyze experimental data and calculate pH value in voxel and ratios of phosphocreatine (PCr)/inorganic phosphate (Pi), PCr/phosphodiesterase (PDE) and phosphomonoesterase (PME)/β-adenosine triphosphate (β-ATP) of various metabolites. 31P MRS results were compared with t test between tumor patients and normal subjects.MAIN OUTCOME MEASURES: Changes of phospholipid metabolism (PME/PDE), energy metabolism (PCr/ATP) and pH value of various cerebral tumors and normal brain tissues.RESULTS: A total of 44 cases with cerebral tumor and 36 normal subjects were involved in the final analysis. pH value and semi-quantitative measurements of normal brain tissues and various cerebral tumors: ① pH value at top occipital region and temple occipital region of normal brain tissue was 7.04±0.02;PCt/β-ATP was 1.51 ±0.03; PCt/Pi was 2.85

  19. Spontaneous calcium waves in Bergman glia increase with age and hypoxia and may reduce tissue oxygen

    DEFF Research Database (Denmark)

    Mathiesen, Claus; Brazhe, Alexey; Thomsen, Kirsten Joan;

    2013-01-01

    Glial calcium (Ca(2+)) waves constitute a means to spread signals between glial cells and to neighboring neurons and blood vessels. These waves occur spontaneously in Bergmann glia (BG) of the mouse cerebellar cortex in vivo. Here, we tested three hypotheses: (1) aging and reduced blood oxygen sa...

  20. Oxygen saturation, red blood cell tissue fraction and speed resolved perfusion - A new optical method for microcirculatory assessment.

    Science.gov (United States)

    Jonasson, Hanna; Fredriksson, Ingemar; Pettersson, Anders; Larsson, Marcus; Strömberg, Tomas

    2015-11-01

    We have developed a new fiber-optic system that combines diffuse reflectance spectroscopy (DRS) and laser Doppler Flowmetry (LDF) for a multi-modal assessment of the microcirculation. Quantitative data is achieved with an inverse Monte Carlo algorithm based on an individually adaptive skin model. The output parameters are calculated from the model and given in absolute units: hemoglobin oxygen saturation (%), red blood cell (RBC) tissue fraction (%), and the speed resolved RBC perfusion separated into three speed regions; 0-1mm/s, 1-10mm/s and above 10mm/s (% mm/s). The aim was to explore microcirculatory parameters using the new optical method, integrating DRS and LDF in a joint skin model, during local heating of the dorsal foot and venous and arterial occlusion of the forearm in 23 healthy subjects (age 20-28years). There were differences in the three speed regions in regard to blood flow changes due to local heating, where perfusion for high speeds increased the most. There was also a high correlation between changes in oxygenation and changes in perfusion for higher speeds. Oxygen saturation at baseline was 44% on foot, increasing to 83% at plateau after heating. The larger increase in perfusion for higher speeds than for lower speeds together with the oxygenation increase during thermal provocation, shows a local thermoregulatory blood flow in presumably arteriolar dermal vessels. In conclusion, there are improved possibilities to assess microcirculation using integrated DRS and LDF in a joint skin model by enabling both oxygenation and speed resolved blood flow assessment simultaneously and in the same skin site. Output parameters in absolute units may also yield new insights about the microcirculatory system.

  1. Total Flavone of Hawthorn Leaf inhibits neuronal apoptosis in brain tissue of rat models of chronic cerebral ischemia

    Institute of Scientific and Technical Information of China (English)

    Tan Rong-fang; Xia Ai-hua; Wu Xiao-guang; Cao Na-na; Li Meng-meng; Zhang Tian-ge; Wang Yi-ru; Yue Zhi-ling

    2014-01-01

    BACKGROUND: Cerebrovascular disease often causes dysfunction of the brain nerve, and nerve cel apoptosis is the important factor of cerebral nerve dysfunction. The excessive expression of c-fos can block the transduction of intracelular signal so that producing some apoptosis-promoting factors, which involve in nerve cel apoptosis process after ischemia injury of brain. Bcl-2 is an inhibited factor. It might to be the key to treat ischemic cerebrovascular disease by inhibiting or reducing the apoptosis of nerve cels after ischemia injury. OBJECTIVE: To investigate the therapeutic effect and mechanism of the Total Flavone of Hawthorn Leaf on chronic cerebral ischemia rats. METHODS: A total of 72 healthy male Sprague-Dawley rats were randomly divided into sham surgery group, model group, Total Flavone of Hawthorn Leaf group and ginkgo leaf group. Permanent bilateral carotid artery ligation was used to prepare chronic cerebral ischemia model in the model group, Total Flavone of Hawthorn Leaf group and ginkgo leaf group. Total Flavone of Hawthorn Leaf group and ginkgo leaf group respectively received 140 mg/kg Total Flavone of Hawthorn Leaf and 12.3 mg/kg ginkgo leaf intragastricaly for 36 days from 36 days after model induction. Model group and sham surgery group received 3.5 mL/kg physiological saline intragastricaly. RESULTS AND CONCLUSION: Compared with the model group, the expression of c-fos protein significantly deceased in the Total Flavone of Hawthorn Leaf group (P 0.05). These data indicated that the protective effect of Total Flavone of Hawthorn Leaf on chronic cerebral ischemia was associated with its inhibition of neuronal apoptosis. Its mechanism of anti-apoptosis might be associated with up-regulating expression of Bcl-2, down-regulating expression of c-fos and decreasing Ca2+ content in brain.

  2. Effect of mild hypothermia on partial pressure of oxygen in brain tissue and brain temperature in patients with severe head injury

    Institute of Scientific and Technical Information of China (English)

    张赛; 只达石; 林欣; 尚彦国; 牛玉德

    2002-01-01

    Objective: To study the changes of partial pressure of oxygen in brain tissue (PbtO2) and brain temperature (BT) in patients in acute phase of severe head injury, and to study the effect of mild hypothermia on PbtO2 and BT.   Methods: The PbtO2 and the BT of 18 patients with severe head injury were monitored, and the patients were treated with mild hypothermia within 20 hours after injury. The rectal temperature (RT) of the patients was kept on 31.5-34.9℃ for 1-7 days (57.7 hours±28.4 hours averagely), simultaneously, the indexes of PbtO2 and BT were monitored for 1-5 days (with an average of 54.8 hours±27.0 hours). According to Glasgow Outcome Scale (GOS), the prognosis of the patients was evaluated at 6 months after injury.   Results: Within 24 hours after severe head injury, the PbtO2 was significantly lower (9.6 mm Hg±6.8 mm Hg, 1 mm Hg=0.133 kPa) than the normal value (16-40 mm Hg). After treatment of mild hypothermia, the mean PbtO2 increased to 28.7 mm Hg±8.8 mm Hg during the first 24 hours, and the PbtO2 was still maintained within the range of normal value at 3 days after injury. The BT was higher than the RT in the patients in acute phase of severe head injury, and the difference between the BT and the RT significantly increased after treatment of mild hypothermia. Hyperventilation (the partial pressure of carbon dioxide in artery (PaCO2)≈25 mm Hg) decreased the high intracranial pressure (ICP) and significantly decreased the PbtO2.   Conclusions: This study demonstrates that PptO2 and BT monitoring is a safe, reliable and sensitive diagnostic method to follow cerebral oxygenation. It might become an important tool in our treatment regime for patients in the acute phase of severe head injury requiring hypothermia and hyperventilation.

  3. Evidence of a Heterogeneous Tissue Oxygenation: Renal Ischemia/Reperfusion Injury in a Large Animal Model

    Science.gov (United States)

    2013-03-01

    administered before vessel occlusion (via vessel loops). Pigs were subjected to normothermic (33°C, n ¼ 2) and hypothermic (5°C, n ¼ 3) ischemia. For...of the hypother- mic kidneys after 30 min of ischemia is approximately 70% of the baseline oxy-hemoglobin concentration, whereas the normo- thermic...normothermic kidneys (−71%, n ¼ 2) after hilar clamping, but that both normothermic and hypother- mic kidneys returned to renal oxygenation levels near 80

  4. Pilot study to visualise and measure skin tissue oxygenation, erythema, total haemoglobin and melanin content using index maps in healthy controls

    Science.gov (United States)

    Poxon, Ian; Wilkinson, Jack; Herrick, Ariane; Dickinson, Mark; Murray, Andrea

    2014-02-01

    We report on a method for analysing multispectral images of skin in vivo for the measurement and visualisation of skin characteristics. Four different indices were used to characterise skin tissue oxygenation, erythema, total haemoglobin and melanin content. Index values were calculated pixel-wise and combined to create index maps to visualise skin properties. Quantitative measurement of tissue oxygenation saturation was possible by calibrating the oxygenation index using a commercial, calibrated oximeter. Index maps were tested by arterial occlusion of the index finger with multispectral images taken before, during and after occlusion in a pilot study with 10 healthy controls.

  5. Gene interference regulates aquaporin-4 expression in swollen tissue of rats with cerebral ischemic edema Correlation with variation in apparent diffusion coefficient

    Institute of Scientific and Technical Information of China (English)

    Hui Hu; Hong Lu; Zhanping He; Xiangjun Han; Jing Chen; Rong Tu

    2012-01-01

    To investigate the effects of mRNA interference on aquaporin-4 expression in swollen tissue of rats with ischemic cerebral edema, and diagnose the significance of diffusion-weighted MRI, we injected 5 μL shRNA- aquaporin-4 (control group) or siRNA- aquaporin-4 solution (1:800) (RNA interference group) into the rat right basal ganglia immediately before occlusion of the middle cerebral artery. At 0.25 hours after occlusion of the middle cerebral artery, diffusion-weighted MRI displayed a high signal; within 2 hours, the relative apparent diffusion coefficient decreased markedly, aquaporin-4 expression increased rapidly, and intracellular edema was obviously aggravated; at 4 and 6 hours, the relative apparent diffusion coefficient slowly returned to control levels, aquaporin-4 expression slightly increased, and angioedema was observed. In the RNA interference group, during 0.25- 6 hours after injection of siRNA- aquaporin-4 solution, the relative apparent diffusion coefficient slightly fluctuated and aquaporin-4 expression was upregulated; during 0.5-4 hours, the relative apparent diffusion coefficient was significantly higher, while aquaporin-4 expression was significantly lower when compared with the control group, and intracellular edema was markedly reduced; at 0.25 and 6 hours, the relative apparent diffusion coefficient and aquaporin-4 expression were similar when compared with the control group; obvious angioedema remained at 6 hours. Pearson's correlation test results showed that aquaporin-4 expression was negatively correlated with the apparent diffusion coefficient (r = -0.806, P < 0.01). These findings suggest that upregulated aquaporin-4 expression is likely to be the main molecular mechanism of intracellular edema and may be the molecular basis for decreased relative apparent diffusion coefficient. Aquaporin-4 gene interference can effectively inhibit the upregulation of aquaporin-4 expression during the stage of intracellular edema with time

  6. Cerebral effects of commonly used vasopressor-inotropes: a study in newborn piglets.

    Directory of Open Access Journals (Sweden)

    Gitte H Hahn

    Full Text Available BACKGROUND: Despite widespread use in sick infants, it is still debated whether vasopressor-inotropes have direct cerebral effects that might affect neurological outcome. We aimed to test direct cerebrovascular effects of three commonly used vasopressor-inotropes (adrenaline, dopamine and noradrenaline by comparing the responses to those of nonpharmacologically induced increases in blood pressure. We also searched for reasons for a mismatch between the response in perfusion and oxygenation. METHODS: Twenty-four piglets had long and short infusions of the three vasopressor-inotropes titrated to raise mean arterial blood pressure (MAP 10 mmHg in random order. Nonpharmacological increases in MAP were induced by inflation of a balloon in the descending aorta. We measured cerebral oxygenation (near-infrared spectroscopy, perfusion (laser-Doppler, oxygen consumption (co-oximetry of arterial and superior sagittal sinus blood, and microvascular heterogeneity (side stream dark field video microscopy. RESULTS: Vasopressor-inotropes increased cerebral oxygenation significantly less (p≤0.01 compared to non-pharmacological MAP increases, whereas perfusion was similar. Furthermore, cerebral total hemoglobin concentration increased significantly less during vasopressor-inotrope infusions (p = 0.001. These physiologic responses were identical between the three vasopressor-inotropes (p>0.05. Furthermore, they induced a mild, although insignificant increase in cerebral metabolism and microvascular heterogeneity (p>0.05. Removal of the scalp tissue did not influence the mismatch (p>0.05. CONCLUSION: We demonstrated a moderate vasopressor-inotrope induced mismatch between cerebral perfusion and oxygenation. Scalp removal did not affect this mismatch, why vasopressor-inotropes appear to have direct cerebral actions. The statistically nonsignificant increases in cerebral metabolism and/or microvascular heterogeneity may explain the mismatch. Alternatively, it

  7. Electro-acupuncture for STAT3 expression and nuclear translocation in hippocampal tissues of rats following cerebral ischemia/reperfusion

    Institute of Scientific and Technical Information of China (English)

    Lihong Kong; Xiaoling Zeng; Guojie Sun; Shenghong Liu

    2006-01-01

    BACKGROUND: It has been found in recent years that STATS widely distributes in nervous system, including hippocampal CA1-3 region, dentate gyrus and cerebral neocortex, etc. Ischemic brain injury can cause the release of some cytokines and growth factors, while electro-acupuncture may have multi-level, multi-channel and multi-target protective and interventional effects on ischemic brain injury.OBJ ECTIVE: To observe the effects of electro-acupuncture on STAT3 expression and nuclear translocation in hippocampal CA1 region of rat models of brain ischemia/reperfusion.DESIGN: Randomized and controlled observation.SETTING: Staff Room of Acupuncture and Moxibustion, Department of Acupuncture and Bone Injury,Hubei College of Traditional Chinese Medicine; Tongji Medical College, Huazhong University of Science and Technology.MATERTALS: Seventy-two healthy SD rats, of clean degree and either gender, weighing (200±20) g, were provided by the Experimental Animal Center of Hubei College of Traditional Chinese Medicine. STAT3monoclonal antibody was purchased from Santa Cruz Company, USA, and G-6805 electro-acupuncture instrument was purchased from Shanghai Medical Electronic Instruments Factory.METHODS: This experiment was carried out in the comprehensive laboratory of Department of Acupuncture and Bone Injury, Hubei College of Traditional Chinese Medicine between September 2005 and February 2006.Seventy-two rats were randomly divided into 4 groups: ① control group(n =6): Untouched. ② Sham-operation group (n =18): Artery was isolated, but without inserting thread bolt.③ Model group (n =24): Rat models of local brain ischemia/reperfusion were established with modified suture occlusion. ④Electro-acupuncture group (n =24): Dazhui and bilateral Neiguan points were selected for electro-acupuncture treatment. No. 28acupuncture needle of 3.33 cm was used in the treatment A G-6085 electro-acupuncture instrument with continuous wave, frequency of 120 times/min, intensity of 1 m

  8. Effects of normobaric versus hyperbaric oxygen on cell injury induced by oxygen and glucose deprivation in acute brain slices.

    Science.gov (United States)

    Chazalviel, Laurent; Blatteau, Jean-Eric; Vallée, Nicolas; Risso, Jean-Jacques; Besnard, Stéphane; Abraini, Jacques H

    2016-01-01

    Normobaric oxygen (NBO) and hyperbaric oxygen (HBO) are emerging as a possible co-treatment of acute ischemic stroke. Both have been shown to reduce infarct volume, to improve neurologic outcome, to promote endogenous tissue plasminogen activator-induced thrombolysis and cerebral blood flow, and to improve tissue oxygenation through oxygen diffusion in the ischemic areas, thereby questioning the interest of HBO compared to NBO. In the present study, in order to investigate and compare the oxygen diffusion effects of NBO and HBO on acute ischemic stroke independently of their effects at the vascular level, we used acute brain slices exposed to oxygen and glucose deprivation, an ex vivo model of brain ischemia that allows investigating the acute effects of NBO (partial pressure of oxygen (pO2) = 1 atmospheres absolute (ATA) = 0.1 MPa) and HBO (pO2 = 2.5 ATA = 0.25 MPa) through tissue oxygenation on ischemia-induced cell injury as measured by the release of lactate dehydrogenase. We found that HBO, but not NBO, reduced oxygen and glucose deprivation-induced cell injury, indicating that passive tissue oxygenation (i.e. without vascular support) of the brain parenchyma requires oxygen partial pressure higher than 1 ATA.

  9. Effect of ultraviolet blood irradiation and oxygenation on nerve function and function of the red blood cell membrane pump in patients with acute cerebral infarction

    Institute of Scientific and Technical Information of China (English)

    Jiaquan Wang; Chun Mao; Kaifu Ma; Shiqing Wang

    2006-01-01

    BACKGROUND: Ultraviolet blood irradiation and oxygenation (UBIO) has obtained better clinical effect in treating acute cerebral infarction, but the mechanism underlying this effect remains unclear.OBJECTIVE: To observe the effect of UBIO on the nerve function and activities of K+-Na+-ATPase and Ca2+-Mg2+-ATPase activities on the red blood cell (RBC) membrane of patients with acute cerebral infarction.DESIGN: A randomized and controlled study.SETTING: Department of Neurology, Xiangfan Central Hospital.PARTICIPANTS: From January 2000 to December 2001, excluding those above 70 years old, 58 cases of 700 patients with acute cerebral infarction admitted in the Department of Neurology, Xiangfan Central Hospital, were recruited and divided into two groups according to the random number table: UBIO treated group (n=28), including 17 males and 11 females, aged 40-68 years; and control group (n=30), including 20males and 10 females, aged 44-69 years. All the patients agreed to participate in the therapeutic program and detected items. The general informations were comparable without obvious differences between the two groups (P > 0.05).METHODS: ① The patients in both groups received routine treatments, besides, those in the UBIO treated group were given UBIO treatment by using the XL-200 type therapeutic apparatus produced in Shijiazhuang, whose ultraviolet wave was set at 253.7 nm with the energy density of 0.568 J/m2 per second, UBIO treatment started from the second day after admission, once every other day, with a single course consisting of 5-7 treatments. ② In the UBIO treated group, the venous blood was sampled before and after the first, third and the completion of the treatment course respectively, the venous blood was taken at each corresponding time point in the control group. After centrifugation of the blood at 10 000 rounds per minute,the RBC membrane was separated and then the activities of K+-Na+-ATPase and Ca2+-Mg2+-ATPase were detected by means of

  10. Cerebral tissue O2 saturation during prolonged robotic surgery in the steep Trendelenburg position: an observational case series in a diverse surgical population.

    Science.gov (United States)

    Lahaye, Laura; Grasso, Mario; Green, Jeffrey; Biddle, C J

    2015-03-01

    Demands associated with the Trendelenburg position (TP) are well known yet there is little attention given to regional cerebral tissue O2 saturation (SctO2) in those undergoing robotic surgery in the TP with CO2 insufflation (C-INSF). This is the first study to report on SctO2 in a wide range of patients undergoing lengthy TP and robotic surgery. We measured SctO2 during robotic surgery in patients in the TP with C-INSF, as well as a control robotic thyroid surgery group who were supine with no C-INSF. We recorded relevant variables and periods of cerebral desaturation (CD). We studied 42 patients in 25°-45° of TP for ≥125 min. Management was at the providers' discretion. The INVOS(®) 5100C Cerebral Oximeter (Covidien, Boulder, CO) recorded SctO2. CD was defined as a >20 % decrease from baseline SctO2 or a value ≤55 % for ≥10 min. Patients were assessed for adverse outcome. The sample consisted of 13 males and 29 females aged 22-73, BMI 22-36 had general (N = 3), urological (N = 14) and gynecological (N = 25) surgery; two patients had CD lasting 150 and 190 min and two had episodic CD lasting 10-35 min. The four were female aged 22-60 in 38°-45° of TP. Eleven cases had multiple episodic CD for ≤15 min, 27 TP cases had no CD. Other observations included a consistent fall in SctO2 with phenylephrine; an increased SctO2 with ephedrine; and FiO2 and EtCO2 being generally strong, direct modifiers of SctO2. High MAP was inconsistently associated with high SctO2. BMI had no observed effect on SctO2. Pulse oximetry was ≥97 % in all cases. We observed no adverse cerebral events on follow-up. Additional clinical studies are warranted.

  11. Improved cerebral oxygenation response and executive performance as a function of cardiorespiratory fitness in older women: a fNIRS study

    Directory of Open Access Journals (Sweden)

    Cédric T Albinet

    2014-10-01

    Full Text Available Cardiorespiratory fitness has been shown to protect and enhance cognitive and brain functions, but little is known about the cortical mechanisms that underlie these changes in older adults. In this study, functional NIRS was used to investigate variations in oxyhemoglobin ([HbO2] and in deoxyhemoglobin ([HHb] in the dorsolateral prefrontal cortex (DLPFC during the performance of an executive control task in older women with different levels of cardiorespiratory fitness (VO2max. Thirty-four women aged 60-77 years were classified as high-fit and low-fit based on VO2max measures. They all performed a control counting task and the Random Number Generation (RNG task at two different paces (1 number / 1 s and 1 number / 1.5 s, allowing to manipulate task difficulty, while hemodynamic responses in the bilateral DLPFCs were recorded using continuous-wave NIRS. The behavioral data revealed that the high-fit women showed significantly better performance on the RNG tasks compared with the low-fit women. The high-fit women showed significant increases in [HbO2] responses in both left and right DLPFCs during the RNG task, while the low-fit women showed significantly less activation in the right DLPFC compared with the right DLPFC of the high-fit women and compared with their own left DLPFC. At the level of the whole sample, increases in the [HbO2] responses in the right DLPFC were found to mediate in part the relationship between VO2max level and executive performance during the RNG task at 1.5 s but not at 1 s. These results provide support for the cardiorespiratory fitness hypothesis and suggest that higher levels of aerobic fitness in older women are related to increased cerebral oxygen supply to the DLPFC, sustaining better cognitive performance.

  12. Clinical Neuroimaging of cerebral ischemia

    Energy Technology Data Exchange (ETDEWEB)

    Nakagawara, Jyoji [Nakamura Memorial Hospital, Sapporo (Japan)

    1999-06-01

    Notice points in clinical imaging of cerebral ischemia are reviewed. When cerebral blood flow is determined in acute stage of cerebral embolism (cerebral blood flow SPECT), it is important to find area of ischemic core and ischemic penumbra. When large cortex area is assigned to ischemic penumbra, thrombolytic therapy is positively adapted, but cautious correspondence is necessary when ischemic core is recognized. DWI is superior in the detection of area equivalent to ischemic core of early stage, but, in imaging of area equivalent to ischemic penumbra, perfusion image or distribution image of cerebral blood volume (CBV) by MRI need to be combined. Luxury perfusion detected by cerebral blood flow SPECT in the cases of acute cerebral embolism suggests vascular recanalization, but a comparison with CT/MRI and continuous assessment of cerebral circulation dynamics were necessary in order to predict brain tissue disease (metabolic abnormality). In hemodynamic cerebral ischemia, it is important to find stage 2 equivalent to misery perfusion by quantification of cerebral blood flow SPECT. Degree of diaschisis can indicate seriousness of brain dysfunction for lacuna infarct. Because cerebral circulation reserve ability (perfusion pressure) is normal in all areas of the low cerebral blood flow by diaschisis mechanism, their areas are easily distinguished from those of hemodynamic cerebral ischemia. (K.H.)

  13. METOVITAN PREVENTS ACCUMULATION OF THIAMIN DIPHOSPHATE OXYGENIZED FORM IN RAT TISSUES UNDER IRRADIATION

    OpenAIRE

    Yu. M. Parkhomenko; G. V. Donchenko; L. I. Chehovskaya; S. P. Stepanenko; O. A. Mejenskaya; E. N. Gorban

    2015-01-01

    The aim of the research was to test the ability of the drug “Metovitan” to prevent the redox balance disturbance in the tissues and thiamine diphosphate irreversible oxidation upon exposure of ionizing radiation on the body. The rats were undergo to a single exposure of the X-ray therapeutic instrument RUM-17 to create a dose of 0.5, 1.0 and 5.0 Gy. Preparation “Metovitan” were administered at a dose of 25 mg per 1 kg body weight for 22–24 h before irradiation. Contents of thiamin...

  14. Simultaneous host and parasite expression profiling identifies tissue-specific transcriptional programs associated with susceptibility or resistance to experimental cerebral malaria

    Directory of Open Access Journals (Sweden)

    Liles W Conrad

    2006-11-01

    Full Text Available Abstract Background The development and outcome of cerebral malaria (CM reflects a complex interplay between parasite-expressed virulence factors and host response to infection. The murine CM model, Plasmodium berghei ANKA (PbA, which simulates many of the features of human CM, provides an excellent system to study this host/parasite interface. We designed "combination" microarrays that concurrently detect genome-wide transcripts of both PbA and mouse, and examined parasite and host transcriptional programs during infection of CM-susceptible (C57BL/6 and CM-resistant (BALB/c mice. Results Analysis of expression data from brain, lung, liver, and spleen of PbA infected mice showed that both host and parasite gene expression can be examined using a single microarray, and parasite transcripts can be detected within whole organs at a time when peripheral blood parasitemia is low. Parasites display a unique transcriptional signature in each tissue, and lung appears to be a large reservoir for metabolically active parasites. In comparisons of susceptible versus resistant animals, both host and parasite display distinct, organ-specific transcriptional profiles. Differentially expressed mouse genes were related to humoral immune response, complement activation, or cell-cell interactions. PbA displayed differential expression of genes related to biosynthetic activities. Conclusion These data show that host and parasite gene expression profiles can be simultaneously analysed using a single "combination" microarray, and that both the mouse and malaria parasite display distinct tissue- and strain-specific responses during infection. This technology facilitates the dissection of host-pathogen interactions in experimental cerebral malaria and could be extended to other disease models.

  15. Recombinant Tissue Plasminogen Activator Induces Neurological Side Effects Independent on Thrombolysis in Mechanical Animal Models of Focal Cerebral Infarction: A Systematic Review and Meta-Analysis.

    Directory of Open Access Journals (Sweden)

    Mei-Xue Dong

    Full Text Available Recombinant tissue plasminogen activator (rtPA is the only effective drug approved by US FDA to treat ischemic stroke, and it contains pleiotropic effects besides thrombolysis. We performed a meta-analysis to clarify effect of tissue plasminogen activator (tPA on cerebral infarction besides its thrombolysis property in mechanical animal stroke.Relevant studies were identified by two reviewers after searching online databases, including Pubmed, Embase, and ScienceDirect, from 1979 to 2016. We identified 6, 65, 17, 12, 16, 12 and 13 comparisons reporting effect of endogenous tPA on infarction volume and effects of rtPA on infarction volume, blood-brain barrier, brain edema, intracerebral hemorrhage, neurological function and mortality rate in all 47 included studies. Standardized mean differences for continuous measures and risk ratio for dichotomous measures were calculated to assess the effects of endogenous tPA and rtPA on cerebral infarction in animals. The quality of included studies was assessed using the Stroke Therapy Academic Industry Roundtable score. Subgroup analysis, meta-regression and sensitivity analysis were performed to explore sources of heterogeneity. Funnel plot, Trim and Fill method and Egger's test were obtained to detect publication bias.We found that both endogenous tPA and rtPA had not enlarged infarction volume, or deteriorated neurological function. However, rtPA would disrupt blood-brain barrier, aggravate brain edema, induce intracerebral hemorrhage and increase mortality rate.This meta-analysis reveals rtPA can lead to neurological side effects besides thrombolysis in mechanical animal stroke, which may account for clinical exacerbation for stroke patients that do not achieve vascular recanalization with rtPA.

  16. Recombinant Tissue Plasminogen Activator Induces Neurological Side Effects Independent on Thrombolysis in Mechanical Animal Models of Focal Cerebral Infarction: A Systematic Review and Meta-Analysis

    Science.gov (United States)

    Wei, You-Dong; Liu, Yi-Yun; Ren, Yi-Fei; Liang, Zi-Hong; Wang, Hai-Yang; Zhao, Li-Bo; Xie, Peng

    2016-01-01

    Background and Purpose Recombinant tissue plasminogen activator (rtPA) is the only effective drug approved by US FDA to treat ischemic stroke, and it contains pleiotropic effects besides thrombolysis. We performed a meta-analysis to clarify effect of tissue plasminogen activator (tPA) on cerebral infarction besides its thrombolysis property in mechanical animal stroke. Methods Relevant studies were identified by two reviewers after searching online databases, including Pubmed, Embase, and ScienceDirect, from 1979 to 2016. We identified 6, 65, 17, 12, 16, 12 and 13 comparisons reporting effect of endogenous tPA on infarction volume and effects of rtPA on infarction volume, blood-brain barrier, brain edema, intracerebral hemorrhage, neurological function and mortality rate in all 47 included studies. Standardized mean differences for continuous measures and risk ratio for dichotomous measures were calculated to assess the effects of endogenous tPA and rtPA on cerebral infarction in animals. The quality of included studies was assessed using the Stroke Therapy Academic Industry Roundtable score. Subgroup analysis, meta-regression and sensitivity analysis were performed to explore sources of heterogeneity. Funnel plot, Trim and Fill method and Egger’s test were obtained to detect publication bias. Results We found that both endogenous tPA and rtPA had not enlarged infarction volume, or deteriorated neurological function. However, rtPA would disrupt blood-brain barrier, aggravate brain edema, induce intracerebral hemorrhage and increase mortality rate. Conclusions This meta-analysis reveals rtPA can lead to neurological side effects besides thrombolysis in mechanical animal stroke, which may account for clinical exacerbation for stroke patients that do not achieve vascular recanalization with rtPA. PMID:27387385

  17. Hyperventilation, cerebral perfusion, and syncope

    DEFF Research Database (Denmark)

    Immink, R V; Pott, F C; Secher, N H

    2014-01-01

    dioxide (PaCO2) and oxygen (PaO2) partial pressures so that hypercapnia/hypoxia increases and hypocapnia/hyperoxia reduces global cerebral blood flow. Cerebral hypoperfusion and TLOC have been associated with hypocapnia related to HV. Notwithstanding pronounced cerebrovascular effects of PaCO2...

  18. Fluctuation of Brain Tissue Oxygen Partial Pressure: A Biochemical Landmark in the Arctic Ground Squirrel's Spontaneous Arousal

    Directory of Open Access Journals (Sweden)

    Yi L. Ma

    2011-01-01

    Full Text Available Hibernation in the Arctic ground Squirrel (AGS is a regulated, adaptive response to arctic environmental conditions. Problem statement: Regional brain Blood Flow (rCBF has been observed to increase dramatically during arousal in hibernators. However, the real time dynamic change in PtO2 during arousal has not been studied, we hypothesized that PtO2 is Interdependent of Tbrain and a key component in the arousal process. Approach: Simultaneous in vivo measurements of PtO2 and brain temperature (Tbrain in conjunction with oxygen consumption (V02 were conducted in the striatum of non-sedated, non-anesthetized Arctic ground squirrels during spontaneous arousal from hibernation. Results: A dramatic fluctuation of brain tissue oxygen partial pressure (PtO2 is associated with the complex phenomena of spontaneous arousal. In this study, we observed that: (1 a PtO2 elevation precedes changes in Tbrain and V02; (2 PtO2 changes do not correlate with changes in V02 during arousal and (3, endogenous O2 shift from O2 enriched blood to brain in hibernating AGS induces an arousal with the pharmaceutical chemical, efaproxiral (RSR-13. Conclusion: The four turning points of PtO2 appearing at different Tbrain during arousal suggest that changes in PtO2 are Tbrain interdependent and support the concept that arousal from hibernation is complex process invoking different feedbacks.

  19. Conservative surgical management of necrotic tissues following meningococcal sepsis: case report of a child treated with hyperbaric oxygen.

    Science.gov (United States)

    Takac, Ines; Kvolik, Slavica; Divkovic, Dalibor; Kalajdzic-Candrlic, Jasenka; Puseljic, Silvija; Izakovic, Senka

    2010-01-01

    This article presents the case of a 5-month-old infant, who survived a fulminant meningococcal sepsis with purpura fulminans, septic shock and severe DIC with gastrointestinal bleeding. Amputation and reconstructive surgery were considered to treat the multiple skin and limb necroses at high risk of superinfection, but the surgical intervention was delayed due to the extremely doubtful outcome. On Day 10 after the onset of the disease, a hemodynamic improvement was achieved. The baby overcame early critical period, but was still in poor general condition. The hyperbaric oxygenation (HBO2) as adjuvant therapy was started in the monoplace chamber using the following protocol: from first through fifth day 45 minutes twice a day on 1.5 atmosphere absolute (ATA); after a two-day break, once a day on 1.8 ATA for 60 minutes. During 52 HBO2 treatments multiple areas of necrotic skin and subcutaneous tissue, together with fingertips and toes, detached spontaneously. All wounds healed without reinfections. An increased oxygen concentration during HBO2 therapy promoted spontaneous wound healing. Bacterial superinfection was not observed in numerous low-perfused lesions. Since repeated anesthesia and surgical interventions were not needed, a final invalidity was minimized. To the best of our knowledge, this is the first report on the successful conservative surgical treatment of this mutilating disease without aggressive reconstructive surgery in an infant with the help of HBO2.

  20. Model-based cell number quantification using online single-oxygen sensor data for tissue engineering perfusion bioreactors.

    Science.gov (United States)

    Lambrechts, T; Papantoniou, I; Sonnaert, M; Schrooten, J; Aerts, J-M

    2014-10-01

    Online and non-invasive quantification of critical tissue engineering (TE) construct quality attributes in TE bioreactors is indispensable for the cost-effective up-scaling and automation of cellular construct manufacturing. However, appropriate monitoring techniques for cellular constructs in bioreactors are still lacking. This study presents a generic and robust approach to determine cell number and metabolic activity of cell-based TE constructs in perfusion bioreactors based on single oxygen sensor data in dynamic perfusion conditions. A data-based mechanistic modeling technique was used that is able to correlate the number of cells within the scaffold (R(2)  = 0.80) and the metabolic activity of the cells (R(2)  = 0.82) to the dynamics of the oxygen response to step changes in the perfusion rate. This generic non-destructive measurement technique is effective for a large range of cells, from as low as 1.0 × 10(5) cells to potentially multiple millions of cells, and can open-up new possibilities for effective bioprocess monitoring.

  1. Clinical study of early hyperbaric oxygen therapy for cerebral resuscitation%早期应用高压氧进行脑复苏的临床研究

    Institute of Scientific and Technical Information of China (English)

    潘树义; 孟祥恩; 李铭鑫; 张禹; 吕艳; 杨晨; 张良; 刘文成

    2011-01-01

    Objective To observe the effect of early hyperbaric oxygen (HBO) therapy on cerebral resuscitation and to provide good evidence and method for the treatment of cerebral resuscitation.Methods The patients responded to cardiac pulmonary resuscitation (CPR) were divided into 2 groups,the early HBO group( within one week of onset) and the delayed HBO group (after 1 week of onset).All the patients were given routine medicinal treatment coupled with HBO therapy.The exposure pressure of HBO and the course of treatment were all the same,only the time point of HBO intervention was different.Evaluation was made by using "the Revised 2001 PVS Criteria for Diagnosis and Treatment" ( the Nanjing Criteria).Consciousness of the patients was evaluated both before HBO therapy and 6 months after onset.Results Of the 18 patients who received early HBO therapy,4 patients recovered and returned to normal life (effective),5 patients became fully conscious,but with minor disability (effective),and 9 patients became vegetable (ineffective),with a total effective rate of 50.0%.Of the 53 patients with delayed HBO therapy,9 patients recovered and returned to normal life (effective),15 patients became fully conscious,but with minor disability (effective),and 29 patients became vegetable (ineffective),with a total effective rate of 45.3%.No significant differences could be seen in effective rates between the 2 groups (P >0.05).However,statistical significance could be noted,when effective rates of the 2 groups were compared with those presented in domestic and international reports (2%-10% ) ( P < 0.05 ).Conclusions In-time HBO therapy could improve prognosis of some patients following cardiac resuscitation,protect neural cells,and improve the intelligence of patients,however,early and ultra-early HBO therapy could not increase the effective rate of cerebral resuscitation.%目的 观察早期高压氧( hyperbaric oxygen,HBO)治疗对脑复苏成功率的影响,为临床脑复苏

  2. Crew Cerebral Oxygen Monitor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This Phase II SBIR proposal is aimed at developing a non-invasive, optical method for monitoring crew member state of awareness in operational environments. All...

  3. Crew Cerebral Oxygen Monitor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This Phase I SBIR proposal is aimed at developing a non-invasive, optical method for monitoring the state of consciousness of crew members in operational...

  4. 组织细胞氧合障碍的机制及其对策%Mechanism and strategy of oxygenation dysfunction in tissue and cell levels

    Institute of Scientific and Technical Information of China (English)

    赵良

    2013-01-01

    According to theory of oxygen transport, mechanism of oxygenation dysfunction in tissue and cell levels can be divided into five types: low oxygen supply, high oxygen consumption, decreased oxygen extraction, oxygen utilization dysfunction and mixed pattern. Up to now, clinically corresponding strategy have been taken. Oxygen supply in global levels can be increased by blood transfusion, use of positive inotropic drugs, elevation of inspired oxygen fraction. Oxygen supply in tissue levels can be elevated by regulation of blood vessel tension, improvement of blood hemorheology. Oxygen consumption can be decreased by anesthesia, sedation, muscle relaxation, hypothermia and mechanical ventilation. Improvement of capillary permeability can increase oxygen uptake by enlargement in diffusion area of oxygen. On basis of osmotic pressure elevation, the edema eliminated by diuresis or dehydration can facilitate oxygen extraction through shortening diffusion distance of oxygen.%依据氧输送原理可以将组织细胞氧合障碍的机制划分为五种类型:①低氧供;②高氧耗;③氧摄取能力减退;④氧利用障碍;⑤混合型.迄今为止,临床上能够采取的相应对策有输血、应用正性肌力药物、提高吸氧浓度以增加系统水平氧供给,调节血管张力、改善血液流变学来增加组织水平氧供给.麻醉、镇静、肌肉松弛、降温和机械通气等措施降低氧耗;改善毛细血管通透性,通过扩大氧弥散面积,增加组织水平氧摄取;在提高胶体渗透压基础上利尿、脱水消除水肿,通过缩短氧弥散距离,易化组织水平氧摄取.

  5. Ataque cerebral

    OpenAIRE

    Takeuchi Tan, Yuri; Fundación Valle de Lili

    1998-01-01

    ¿Qué es un ataque cerebral?/¿Qué tipos de ataque cerebral existen?/¿Cuáles son los síntomas de un ataque cerebral?/Factores de riesgo para un ataque cerebral/Tratamiento médico del ataque cerebral/¿por qué es importante acudir temprano cuando se presentan las señales de alarma?/ Manejo preventivo del ataque cerebral isquémico/Tratamiento quirúrgico del ataque cerebral/Enfermedad vascular cerebral hemorrágica/¿Cómo está constituido el grupo de ataque cerebral de la fundación Clínica Valle d...

  6. Light-Addressable Measurement of in Vivo Tissue Oxygenation in an Unanesthetized Zebrafish Embryo via Phase-Based Phosphorescence Lifetime Detection

    Directory of Open Access Journals (Sweden)

    Shih-Hao Huang

    2015-04-01

    Full Text Available We have developed a digital light modulation system that utilizes a modified commercial projector equipped with a laser diode as a light source for quantitative measurements of in vivo tissue oxygenation in an unanesthetized zebrafish embryo via phase-based phosphorescence lifetime detection. The oxygen-sensitive phosphorescent probe (Oxyphor G4 was first inoculated into the bloodstream of 48 h post-fertilization (48 hpf zebrafish embryos via the circulation valley to rapidly disperse probes throughout the embryo. The unanesthetized zebrafish embryo was introduced into the microfluidic device and immobilized on its lateral side by using a pneumatically actuated membrane. By controlling the illumination pattern on the digital micromirror device in the projector, the modulated excitation light can be spatially projected to illuminate arbitrarily-shaped regions of tissue of interest for in vivo oxygen measurements. We have successfully measured in vivo oxygen changes in the cardiac region and cardinal vein of a 48 hpf zebrafish embryo that experience hypoxia and subsequent normoxic conditions. Our proposed platform provides the potential for the real-time investigation of oxygen distribution in tissue microvasculature that relates to physiological stimulation and diseases in a developing organism.

  7. Cerebral energy metabolism during mitochondrial dysfunction induced by cyanide in piglets

    DEFF Research Database (Denmark)

    Nielsen, Troels Halfeld; Olsen, N.V.; Toft, P;

    2013-01-01

    variables related to energy metabolism. METHODS: Mitochondrial dysfunction was induced in piglets and evaluated by monitoring brain tissue oxygen tension (PbtO2 ) and cerebral levels of glucose, lactate, pyruvate, glutamate, and glycerol bilaterally. The biochemical variables were obtained by microdialysis...... metabolism and degradation of cellular membranes, respectively. CONCLUSION: Mitochondrial dysfunction is characterised by an increased LP ratio signifying a shift in cytoplasmatic redox state at normal or elevated PbtO2 . The condition is biochemically characterised by a marked increase in cerebral lactate...... with a normal or elevated pyruvate level. The metabolic pattern is different from cerebral ischemia, which is characterised by simultaneous decreases in intracerebral pyruvate and PbtO2 . The study supports the hypothesis that cerebral ischemia and mitochondrial dysfunction may be identified and separated...

  8. Cerebral Palsy. Fact Sheet = La Paralisis Cerebral. Hojas Informativas Sobre Discapacidades.

    Science.gov (United States)

    National Information Center for Children and Youth with Disabilities, Washington, DC.

    This fact sheet on cerebral palsy is written in both English and Spanish. First, it provides a definition of cerebral palsy and considers various causes (e.g., an insufficient amount of oxygen reaching the fetal or newborn brain). The fact sheet then offers incidence figures and explains characteristics of the three main types of cerebral palsy:…

  9. Carbon dioxide, oxygen, and pH detection in animal adipose tissue by means of extracorporeal microdialysis

    Science.gov (United States)

    Baldini, F.; Bizzarri, A.; Cajlakovic, M.; Feichtner, F.; Gianesello, L.; Giannetti, A.; Gori, G.; Konrad, C.; Mencaglia, A. A.; Mori, E.; Pavoni, V.; Perna, A. M.; Trono, C.

    2007-05-01

    Atypical physiological symptoms can be developed in healthy people under critically ill conditions. pH, pO II and pCO II are informative indicators of the conditions of a living system and can be valuable in determining the physiologic status of the critically ill patients. The continuous monitoring of these small molecules into the interstitial fluid (ISF) is a promising approach to reduce diagnostic blood loss and painful stress associated with blood sampling. Microdialysis is the approach followed for the extraction of the sample from the subcutaneous adipose tissue; the drawn interstitial fluid flows through a microfluidic circuit formed by the microdialysis catheter in series with a glass capillary on the internal wall of which the appropriate chemistry for sensing is immobilised. Absorption changes for pH sensor and modulation of the fluorescence lifetime for pO II and pCO II are the working principle. Phenol red covalently bound into the internal wall of a glass capillary by means of the Mannich reaction and platinum(II) tetrakis-pentafluorophenyl-porphyrine entrapped within a polymerised polystyrene layer are the chemical transducers used for pH and oxygen detection; the ion pair 8- hydroxypyrene-1,3,6-trisulfonic acid trisodium salt/ tetraoctylammonium hydroxide, dissolved in a silicon-based polymeric matrix, is used for the carbon dioxide detection. A suitable hemorrhagic shock model was developed in order to validate clinically the developed sensors in the condition of extreme stress and the obtained results show that the adipose tissue can become an alternative site for the continuous oitoring of pH, pO II and pCO II.

  10. Treadmill exercise induces neutrophil recruitment into muscle tissue in a reactive oxygen species-dependent manner. An intravital microscopy study.

    Directory of Open Access Journals (Sweden)

    Albená Nunes-Silva

    Full Text Available Intense exercise is a physiological stress capable of inducing the interaction of neutrophils with muscle endothelial cells and their transmigration into tissue. Mechanisms driving this physiological inflammatory response are not known. Here, we investigate whether production of reactive oxygen species is relevant for neutrophil interaction with endothelial cells and recruitment into the quadriceps muscle in mice subjected to the treadmill fatiguing exercise protocol. Mice exercised until fatigue by running for 56.3±6.8 min on an electric treadmill. Skeletal muscle was evaluated by intravital microscopy at different time points after exercise, and then removed to assess local oxidative stress and histopathological analysis. We observed an increase in plasma lactate and creatine kinase (CK concentrations after exercise. The numbers of monocytes, neutrophils, and lymphocytes in blood increased 12 and 24 hours after the exercise. Numbers of rolling and adherent leukocytes increased 3, 6, 12, and 24 hours post-exercise, as assessed by intravital microscopy. Using LysM-eGFP mice and confocal intravital microscopy technology, we show that the number of transmigrating neutrophils increased 12 hours post-exercise. Mutant gp91phox-/- (non-functional NADPH oxidase mice and mice treated with apocynin showed diminished neutrophil recruitment. SOD treatment promoted further adhesion and transmigration of leukocytes 12 hours after the exercise. These findings confirm our hypothesis that treadmill exercise increases the recruitment of leukocytes to the postcapillary venules, and NADPH oxidase-induced ROS plays an important role in this process.

  11. Increasing mean arterial pressure in cardiogenic shock secondary to myocardial infarction: effects on hemodynamics and tissue oxygenation.

    Science.gov (United States)

    Perez, Pierre; Kimmoun, Antoine; Blime, Vincent; Levy, Bruno

    2014-04-01

    There are very few data regarding the effects of norepinephrine uptitration on global and regional hemodynamics in cardiogenic shock. We studied 25 patients with shock secondary to myocardial infarction successfully treated with percutaneous coronary intervention. Before the inclusion, 16 of 25 patients presented a cardiac arrest in the presence of medical staff. Norepinephrine was titrated to increase mean arterial pressure (MAP) from 65 to 85 mmHg during 1 h. Swan-Ganz variables, arterial and mixed venous blood gases, lactate, and thenar near-infrared spectroscopy variables (muscle tissue oxygen saturation [StO2] and its changes during a vascular occlusion test) were measured before, 1 h after norepinephrine uptitration, and 1 h after norepinephrine downtitration. To obtain a MAP at 85 mmHg, norepinephrine was increased from 0.6 (0.28-1.2) to 1.53 µg · kg · min (0.76-2.6 µg · kg · min) (P cardiogenic shock complicated by postreperfusion disease is associated with better cardiac performance and improved microcirculatory variables.

  12. A stereotaxic, population-averaged T1w ovine brain atlas including cerebral morphology and tissue volumes.

    Science.gov (United States)

    Nitzsche, Björn; Frey, Stephen; Collins, Louis D; Seeger, Johannes; Lobsien, Donald; Dreyer, Antje; Kirsten, Holger; Stoffel, Michael H; Fonov, Vladimir S; Boltze, Johannes

    2015-01-01

    Standard stereotaxic reference systems play a key role in human brain studies. Stereotaxic coordinate systems have also been developed for experimental animals including non-human primates, dogs, and rodents. However, they are lacking for other species being relevant in experimental neuroscience including sheep. Here, we present a spatial, unbiased ovine brain template with tissue probability maps (TPM) that offer a detailed stereotaxic reference frame for anatomical features and localization of brain areas, thereby enabling inter-individual and cross-study comparability. Three-dimensional data sets from healthy adult Merino sheep (Ovis orientalis aries, 12 ewes and 26 neutered rams) were acquired on a 1.5 T Philips MRI using a T1w sequence. Data were averaged by linear and non-linear registration algorithms. Moreover, animals were subjected to detailed brain volume analysis including examinations with respect to body weight (BW), age, and sex. The created T1w brain template provides an appropriate population-averaged ovine brain anatomy in a spatial standard coordinate system. Additionally, TPM for gray (GM) and white (WM) matter as well as cerebrospinal fluid (CSF) classification enabled automatic prior-based tissue segmentation using statistical parametric mapping (SPM). Overall, a positive correlation of GM volume and BW explained about 15% of the variance of GM while a positive correlation between WM and age was found. Absolute tissue volume differences were not detected, indeed ewes showed significantly more GM per bodyweight as compared to neutered rams. The created framework including spatial brain template and TPM represent a useful tool for unbiased automatic image preprocessing and morphological characterization in sheep. Therefore, the reported results may serve as a starting point for further experimental and/or translational research aiming at in vivo analysis in this species.

  13. A stereotaxic, population-averaged T1w ovine brain atlas including cerebral morphology and tissue volumes

    Directory of Open Access Journals (Sweden)

    Björn eNitzsche

    2015-06-01

    Full Text Available Standard stereotaxic reference systems play a key role in human brain studies. Stereotaxic coordinate systems have also been developed for experimental animals including non-human primates, dogs and rodents. However, they are lacking for other species being relevant in experimental neuroscience including sheep. Here, we present a spatial, unbiased ovine brain template with tissue probability maps (TPM that offer a detailed stereotaxic reference frame for anatomical features and localization of brain areas, thereby enabling inter-individual and cross-study comparability. Three-dimensional data sets from healthy adult Merino sheep (Ovis orientalis aries, 12 ewes and 26 neutered rams were acquired on a 1.5T Philips MRI using a T1w sequence. Data were averaged by linear and non-linear registration algorithms. Moreover, animals were subjected to detailed brain volume analysis including examinations with respect to body weight, age and sex. The created T1w brain template provides an appropriate population-averaged ovine brain anatomy in a spatial standard coordinate system. Additionally, TPM for gray (GM and white (WM matter as well as cerebrospinal fluid (CSF classification enabled automatic prior-based tissue segmentation using statistical parametric mapping (SPM. Overall, a positive correlation of GM volume and body weight explained about 15% of the variance of GM while a positive correlation between WM and age was found. Absolute tissue volume differences were not detected, indeed ewes showed significantly more GM per bodyweight as compared to neutered rams. The created framework including spatial brain template and TPM represent a useful tool for unbiased automatic image preprocessing and morphological characterization in sheep. Therefore, the reported results may serve as a starting point for further experimental and/or translational research aiming at in vivo analysis in this species.

  14. Non-invasive assessment of cerebral microcirculation with diffuse optics and coherent hemodynamics spectroscopy

    Science.gov (United States)

    Fantini, Sergio; Sassaroli, Angelo; Kainerstorfer, Jana M.; Tgavalekos, Kristen T.; Zang, Xuan

    2016-03-01

    We describe the general principles and initial results of coherent hemodynamics spectroscopy (CHS), which is a new technique for the quantitative assessment of cerebral hemodynamics on the basis of dynamic near-infrared spectroscopy (NIRS) measurements. The two components of CHS are (1) dynamic measurements of coherent cerebral hemodynamics in the form of oscillations at multiple frequencies (frequency domain) or temporal transients (time domain), and (2) their quantitative analysis with a dynamic mathematical model that relates the concentration and oxygen saturation of hemoglobin in tissue to cerebral blood volume (CBV), cerebral blood flow (CBF), and cerebral metabolic rate of oxygen (CMRO2). In particular, CHS can provide absolute measurements and dynamic monitoring of CBF, and quantitative measures of cerebral autoregulation. We report initial results of CBF measurements in hemodialysis patients, where we found a lower CBF (54 +/- 16 ml/(100 g-min)) compared to a group of healthy controls (95 +/- 11 ml/(100 g-min)). We also report CHS measurements of cerebral autoregulation, where a quantitative index of autoregulation (its cutoff frequency) was found to be significantly greater in healthy subjects during hyperventilation (0.034 +/- 0.005 Hz) than during normal breathing (0.017 +/- 0.002 Hz). We also present our approach to depth resolved CHS, based on multi-distance, frequency-domain NIRS data and a two-layer diffusion model, to enhance sensitivity to cerebral tissue. CHS offers a potentially powerful approach to the quantitative assessment and continuous monitoring of local brain perfusion at the microcirculation level, with prospective brain mapping capabilities of research and clinical significance.

  15. Cerebral near infrared spectroscopy oximetry in extremely preterm infants

    DEFF Research Database (Denmark)

    Hyttel-Sorensen, Simon; Pellicer, Adelina; Alderliesten, Thomas;

    2015-01-01

    OBJECTIVE: To determine if it is possible to stabilise the cerebral oxygenation of extremely preterm infants monitored by cerebral near infrared spectroscopy (NIRS) oximetry. DESIGN: Phase II randomised, single blinded, parallel clinical trial. SETTING: Eight tertiary neonatal intensive care units...

  16. Cerebral Palsy

    Science.gov (United States)

    Cerebral palsy is a group of disorders that affect a person's ability to move and to maintain balance ... do not get worse over time. People with cerebral palsy may have difficulty walking. They may also have ...

  17. Cytochrome c oxidase response to changes in cerebral oxygen delivery in the adult brain shows higher brain-specificity than haemoglobin ☆

    OpenAIRE

    Kolyva, Christina; Ghosh, Arnab; Tachtsidis, Ilias; Highton, David; Chris E Cooper; Smith, Martin; Elwell, Clare E.

    2014-01-01

    The redox state of cerebral mitochondrial cytochrome c oxidase monitored with near-infrared spectroscopy (Δ[oxCCO]) is a signal with strong potential as a non-invasive, bedside biomarker of cerebral metabolic status. We hypothesised that the higher mitochondrial density of brain compared to skin and skull would lead to evidence of brain-specificity of the Δ[oxCCO] signal when measured with a multi-distance near-infrared spectroscopy (NIRS) system. Measurements of Δ[oxCCO] as well as of concen...

  18. Brain tissue oxygen tension and its response to physiological manipulations: influence of distance from injury site in a swine model of traumatic brain injury.

    Science.gov (United States)

    Hawryluk, Gregory W J; Phan, Nicolas; Ferguson, Adam R; Morabito, Diane; Derugin, Nikita; Stewart, Campbell L; Knudson, M Margaret; Manley, Geoffrey; Rosenthal, Guy

    2016-11-01

    OBJECTIVE The optimal site for placement of tissue oxygen probes following traumatic brain injury (TBI) remains unresolved. The authors used a previously described swine model of focal TBI and studied brain tissue oxygen tension (PbtO2) at the sites of contusion, proximal and distal to contusion, and in the contralateral hemisphere to determine the effect of probe location on PbtO2 and to assess the effects of physiological interventions on PbtO2 at these different sites. METHODS A controlled cortical impact device was used to generate a focal lesion in the right frontal lobe in 12 anesthetized swine. PbtO2 was measured using Licox brain tissue oxygen probes placed at the site of contusion, in pericontusional tissue (proximal probe), in the right parietal region (distal probe), and in the contralateral hemisphere. PbtO2 was measured during normoxia, hyperoxia, hypoventilation, and hyperventilation. RESULTS Physiological interventions led to expected changes, including a large increase in partial pressure of oxygen in arterial blood with hyperoxia, increased intracranial pressure (ICP) with hypoventilation, and decreased ICP with hyperventilation. Importantly, PbtO2 decreased substantially with proximity to the focal injury (contusion and proximal probes), and this difference was maintained at different levels of fraction of inspired oxygen and partial pressure of carbon dioxide in arterial blood. In the distal and contralateral probes, hypoventilation and hyperventilation were associated with expected increased and decreased PbtO2 values, respectively. However, in the contusion and proximal probes, these effects were diminished, consistent with loss of cerebrovascular CO2 reactivity at and near the injury site. Similarly, hyperoxia led to the expected rise in PbtO2 only in the distal and contralateral probes, with little or no effect in the proximal and contusion probes, respectively. CONCLUSIONS PbtO2 measurements are strongly influenced by the distance from the

  19. RBC-coupled tPA prevents cerebrovasodilatory impairment and tissue injury in pediatric cerebral hypoxia/ischemia through inhibition of ERK MAPK unregulation

    Energy Technology Data Exchange (ETDEWEB)

    Ganguly, Kumkum [Los Alamos National Laboratory; Armstead, William M [U PENNSYLVANIA; Kiessling, J W [U PENNSYLVANIA; Chen, Xiao - Han [U PENNSYLVANIA; Smith, Douglas H [U PENNSYLVANA; Higazi, Abd Ar [U PENNSYLVANIA; Cines, Douglas B [U PENNSYLVANIA; Bdeir, Khalil [U PENNSYLVANIA; Zaitsev, Sergei [U PENNSYLVANIA; Muzykantov, Vladimir R [U PENNSYLVANIA

    2008-01-01

    Babies experience hypoxia (H) and ischemia (I) from stroke. The only approved treatment for stroke is fibrinolytic therapy with tissue-type plasminogen activator (tPA). However, tPA potentiates H/I-induced impairment of responses to cerebrovasodilators such as hypercapnia and hypotension, and blockade of tPA-mediated vasoactivity prevents this deleterious effect. Coupling tPA to RBCs reduces its CNS toxicity through spatially confining the drug to the vasculature. Mitogen activated protein kinase (MAPK), a family of at least 3 kinases, is upregulated after H/I. In this study we determined if RBC-tPA given before or after cerebral H/I would preserve responses to cerebrovasodilators and prevent neuronal injury mediated through the ERK MAPK pathway. Animals given RBC-tPA maintained responses to cerebrovasodilators at levels equivalent to pre-H/I values. CSF and brain parenchymal ERK MAPK was elevated by H/I and this upregulation was potentiated by tPA, but blunted by RBC-tPA. U 0126, an ERK MAPK antagonist, also maintained cerebrovasodilation post H/I. Neuronal degeneration in CA1 hippocampus and parietal cortex after H/I was exacerbated by tPA, but ameliorated by RBC-tPA and U 0126. These data suggest that coupling tPA to RBCs may offer a novel approach towards increasing the benefit/risk ratio of thrombolytic therapy for CNS disorders associated with H/I.

  20. Single-stage multilevel soft-tissue surgery in the lower limbs with spastic cerebral palsy: Experience from a rehabilitation unit

    Directory of Open Access Journals (Sweden)

    Gupta Anupam

    2008-01-01

    Full Text Available Background: To assess the effect of single-stage multilevel soft-tissue surgery (Single Event Multiple Level Resections, SEMLR on deformities and locomotion in patients with cerebral palsy (CP with static contracture(s in lower limbs. Patients and Methods: Study included 34 patients (M:F, 23:11 with mean age of 9.53 ± 3.92 years (4-16 years. Among them 22 had diplegia and four each had quadriplegia and right and left hemiplegia. Fourteen patients (41.2% had their intelligence quotient (IQ in the normal range (IQ ≥ 80, while others had mental retardation (MR of varying severity: borderline MR (IQ = 70-79 in 12, mild MR (IQ = 50-69 in 5, and moderate MR (IQ = 35-49 in patients 3. All patients underwent surgery (total number of procedures 153, average 4.5 procedures/patient over a period of 30 months (April 2005 to September 2007. Improvement in functional abilities and locomotion was assessed using Gross Motor Functional Classification Scale (GMFCS scores and by physical examination. Results: Significant improvement in function was observed ( P = 0.000 after surgery when comparing the preoperative and postoperative GMFCS scores. All patients were maintaining ambulation at a mean follow-up duration of 13.12 ± 6.07 months (3-24 months, with five patients using knee-ankle-foot orthoses (KAFO, 22 using ankle-foot orthoses (AFO, and six patients using knee gaiters. Sixteen patients were using walker, and two were using crutches as assistive devices. Conclusion: This study suggests that CP patients with good trunk control and static contractures at multiple joints in the lower limbs can be made ambulant with single-stage multilevel soft-tissue surgery. It has to be a team effort of the surgeon and the rehabilitation team in the postoperative period for the attainment of satisfactory goal.

  1. Cerebral malaria Malaria cerebral

    Directory of Open Access Journals (Sweden)

    Silvia Blair Trujillo

    2003-03-01

    Full Text Available Is the most common complication of P. falciparum malaria; nearly 90% of people who have suffered CM can recover without neurological problems. Currently there are four hypotheses that explain pathogenesis of CM: cytoadherence and sequestering of parasitized red blood cells to cerebral capillaries; rosette formation and parasitized red blood cells agglutination; production of cytokines and activation of second messengers and opening of the blood-brain barrier. However the main question remains to be answered; how the host-parasite interaction in the vascular space interferes transiently with cerebral function? Recently, the beta amyloid precursor peptide has been employed as marker of neural injury in CM. It is expected that the beta amyloid precursor peptide will help to understand the pathogenesis of CM in complicated patients of endemic areas of Colombia. La malaria Cerebral (MC es la complicación más frecuente de la malaria por P. falciparum; aproximadamente el 90% de las personas que la han padecido se recuperan completamente sin secuelas neurológicas. Aún no se conoce con claridad su patogénesis pero se han postulado cuatro hipótesis o mecanismos posibles: 1 citoadherencia y secuestro de glóbulos rojos parasitados en la microvasculatura cerebral; 2 formación de rosetas y aglutinación de glóbulos rojos parasitados; 3 producción de citoquinas y activación de segundos mensajeros y, 4 apertura de la barrera hematoencefálica. Sin embargo, queda un interrogante sin resolver aún: ¿qué proceso se lleva a cabo para que el parásito, desde el espacio microvascular, pueda interferir transitoriamente con la función cerebral? Recientemente se ha utilizado el precursor de la proteína b-Amiloide como un marcador de daño neuronal en MC; este precursor será de gran ayuda en futuras investigaciones realizadas en nuestro medio que aporten información para comprender la patogénesis de la MC.

  2. Absolute measurement of cerebral optical coefficients, hemoglobin concentration and oxygen saturation in old and young adults with near-infrared spectroscopy

    Science.gov (United States)

    We present near-infrared spectroscopy measurement of absolute cerebral hemoglobin concentration and saturation in a large sample of 36 healthy elderly (mean age, 85 ± 6 years) and 19 young adults (mean age, 28 ± 4 years). Non-invasive measurements were obtained on the forehead using a commercially a...

  3. Effect of chronic usage of tramadol on motor cerebral cortex and testicular tissues of adult male albino rats and the effect of its withdrawal: histological, immunohistochemical and biochemical study

    Science.gov (United States)

    Ghoneim, Fatma M; Khalaf, Hanaa A; Elsamanoudy, Ayman Z; Helaly, Ahmed N

    2014-01-01

    This study was designed to demonstrate the histopathological and biochemical changes in rat cerebral cortex and testicles due to chronic usage of tramadol and the effect of withdrawal. Thirty adult male rats weighing 180-200 gm were classified into three groups; group I (control group) group II (10 rats received 50 mg/kg/day of tramadol intraperitoneally for 4 weeks) and group III (10 rats received the same dose as group II then kept 4 weeks later to study the effect of withdrawal). Histological and immunohistochemical examination of cerebral cortex and testicular specimens for Bax (apoptotic marker) were carried out. Testicular specimens were examined by electron microscopy. RT-PCR after RNA extraction from both specimens was done for the genes of some antioxidant enzymes .Also, malondialdehyde (MDA) was measured colourimetrically in tissues homogenizate. The results of this study demonstrated histological changes in testicular and brain tissues in group II compared to group I with increased apoptotic index proved by increased Bax expression. Moreover in this group increased MDA level with decreased gene expression of the antioxidant enzymes revealed oxidative stress. Group III showed signs of improvement but not returned completely normal. It could be concluded that administration of tramadol have histological abnormalities on both cerebral cortex and testicular tissues associated with oxidative stress in these organs. Also, there is increased apoptosis in both organs which regresses with withdrawal. These findings may provide a possible explanation for delayed fertility and psychological changes associated with tramadol abuse. PMID:25550769

  4. Comparative analysis of lower extremities tissue perfusion by the use of perfusion scintigraphy method after hyperbaric oxygenation and lumbar sympathectomy

    Directory of Open Access Journals (Sweden)

    Zoranović Uroš

    2009-01-01

    Full Text Available Background/Aim. Lumbar syphatectomy (LS increases pheripheral blood flow primarily by the arteriolar vasodilatation within the skin vascular net. Increase in tissue nutrition takes place only in the distal blood vessels of the skin. Nevertheless, in some patients sympathectomy brings about improvement in ischemic ulcerations healing. Hyperbaric oxigenation (HBO is a medical treatment in which a patient breathes 100% oxygen under pressure higher than atmospheric implemented in special units allowing the whole body be in a chamber. The aim of the study was to determine efficacy of the applied therapies for the treatment of inoperable occlusive lower extremities (LE arteries diseases according to the obtained results. Methods. The study included 30 patients divided into two groups (15 patients each in which stenosis level of the lower extremities arteries had been determined using aortography due to further treatment with HBO and LS. All the patients were clinically examined, their objective condition evaluation based on claudication distance, pain in rest, skin and skin adnexa atrophy, and temperature and LE functionality, as well as exposed to perfusion scintigraphy prior to the treatment and within 30 days after the treatment finishing. Results. Analyzing patients' status prior to and after the treatments applied the number of patients with obvious improvement was higher in those treated by HBO than those treated by LS. Measuring claudication distance revealed significantly greater changes in patients treated by HBO (from 178.57 m to 754.76 m than in those treated by LS (from 229 m to 253 m. Other clinical symptoms, such as parasthesia, status of the skin adnexes (hair, nails, skin colour and temperature were also improved after the treatment by HBO. Conclusion. The results obatined in this study confirm the advantages of HBO over LS in therapy of inoperable occlusive LE disease, so LS could be definitely abandoned as a choice for treating such

  5. Relationship between level of forage intake, blood flow and oxygen consumption by splanchnic tissues of sheep fed a tropical grass forage.

    Science.gov (United States)

    Hentz, F; Kozloski, G V; Zeni, D; Brun, M V; Stefanello, S

    2017-02-01

    Four Polwarth castrated male sheep (42 ± 4.4 kg live weight (LW) surgically implanted with chronic indwelling catheters into the mesenteric, portal and hepatic veins, housed in metabolism cages and offered Cynodon sp. hay at rates (g of dry matter (DM)/kg LW) of 7, 14, 21 or ad libitum, were used in a 4 × 4 Latin square experiment to evaluate the effect of the level of forage intake on blood flow and oxygen consumption by the portal-drained viscera (PDV), liver and total splanchnic tissues (ST). The portal blood flow and the oxygen consumption by PDV linearly increased at increased organic matter (OM) intake. No effect of level of OM intake was obtained for the hepatic artery blood flow and oxygen consumption by liver. As a consequence, the level of OM intake only tended to directly affect hepatic blood flow and oxygen consumption by total ST. Oxygen consumption was linearly and positively related to blood flow across PDV, liver and total ST. The heat production by PDV and total ST, as proportion of metabolizable energy (ME) intake, decreased curvilinearly at increased ME intake. In conclusion, the oxygen consumption by PDV, but not by liver, was directly related to the level of forage intake by sheep. Moreover, when ingested at levels below maintenance, most of ME was spent as heat produced by ST.

  6. Neuroprotective effects of daidzein on focal cerebral ischemia injury in rats

    Directory of Open Access Journals (Sweden)

    Adem Bozkurt Aras

    2015-01-01

    Full Text Available Daidzein, a plant extract, has antioxidant activity. It is hypothesized, in this study, that daidzein exhibits neuroprotective effects on cerebral ischemia. Rat models of middle cerebral artery occlusion were intraperitoneally administered daidzein. Biochemical and immunohistochemical tests showed that superoxide dismutase and nuclear respiratory factor 1 expression levels in the brain tissue decreased after ischemia and they increased obviously after daidzein administration; malondialdehyde level and apoptosis-related cysteine peptidase caspase-3 and caspase-9 immunoreactivity in the brain tissue increased after ischemia and they decreased obviously after daidzein administration. Hematoxylin-eosin staining and luxol fast blue staining results showed that intraperitoneal administration of daidzein markedly alleviated neuronal damage in the ischemic brain tissue. These findings suggest that daidzein exhibits neuroprotective effects on ischemic brain tissue by decreasing oxygen free radical production, which validates the aforementioned hypothesis

  7. Neuroprotective effects of daidzein on focal cerebral ischemia injury in rats

    Institute of Scientific and Technical Information of China (English)

    Adem Bozkurt Aras; Mustafa Guven; Tark Akman; Adile Ozkan; Halil Murat Sen; Ugur Duz; Yldray Kalkan; Coskun Silan; Murat Cosar

    2015-01-01

    Daidzein, a plant extract, has antioxidant activity. It is hypothesized, in this study, that daidzein exhibits neuroprotective effects on cerebral ischemia. Rat models of middle cerebral artery oc-clusion were intraperitoneally administered daidzein. Biochemical and immunohistochemical tests showed that superoxide dismutase and nuclear respiratory factor 1 expression levels in the brain tissue decreased after ischemia and they increased obviously after daidzein administra-tion; malondialdehyde level and apoptosis-related cysteine peptidase caspase-3 and caspase-9 immunoreactivity in the brain tissue increased after ischemia and they decreased obviously after daidzein administration. Hematoxylin-eosin staining and luxol fast blue staining results showed that intraperitoneal administration of daidzein markedly alleviated neuronal damage in the ischemic brain tissue. These ifndings suggest that daidzein exhibits neuroprotective effects on ischemic brain tissue by decreasing oxygen free radical production, which validates the afore-mentioned hypothesis.

  8. Effects of exposing rats to 100% oxygen at 450 and 600 mm Hg on in vitro liver and adipose tissue lipid synthesis.

    Science.gov (United States)

    Feller, D. D.; Neville, E. D.; Talarico, K. S.

    1972-01-01

    Male rats (260-285 gm) were exposed to 100% oxygen at 450 or 600 mm Hg for 1 to 4 days. Rats maintained at 450 mm Hg ate 92% the amount of food eaten by ad libitum controls maintained at sea level conditions. At 600 mm Hg, the food intake was 77% of the ad libitum controls. No difference was found in the plasma level of glucose, free fatty acids, and corticosterone between oxygen exposed rats and their respective pair-fed controls. The in vitro conversion of acetate into fatty acids by adipose tissue from rats exposed at 450 mm Hg for 2, 3, or 4 days was significantly increased above pair-fed controls and ad libitum controls. Increasing the oxygen pressure to 600 mm Hg abolished this increase, and in fact, reversed the increased synthesis to a significant decrease for the 4-day exposure.

  9. 早期脓毒症大鼠脑氧代谢与乳酸的变化%Preliminary study of cerebral oxygen metabolism and change of blood lactate in early stage of sepsis in rats

    Institute of Scientific and Technical Information of China (English)

    钱欣; 郑峥; 汤罗嘉; 陈锋

    2011-01-01

    Objective To observe the change of cerebral oxygen metablism and the level of blood lactate in early stage of sepsis in rats.Method Sixty-four SD rats were randomly(random number)divided into septic group and control group.The sepsis model of rat was made by lipopolysaccharide (LPS,10 mg/kg)injected intra-abdominally,and rats of control group were treated with the same amount of physiological saline instead.And each group was further divided into 4 sub-groups of4 h,6 h,12 h and 24 h after treatment.At each interval,blood samples were obtained via jugular vein for detecting blood oxygen saturation (Sjv02)and blood lactate(LA).The blood oxygen saturation(Sa02)of ventral aorta was also measured.Arteriovenous oxygen content difference (AVD02) and oxygen extraction fraction (OEF) were studied.These four variables were analyzed and compared between two groups.Results The AVD02 and OEF in sepsis group were higher than those in control groups of 3 h,6 h and 12 h (P0.05).LA in sepsis group was higher than that in control group in each interval (P0.05).脓毒症组各时间点LA含量与对照组相比均有不同程度升高,差异具有统计学意义(P<0.05).结论 脓毒症早期可出现脑贯注及脑氧摄取的增强;Sjv02,AVDO2,OEF结合LA水平的监测,能更准确的评估脓毒症早期脑供氧、耗氧和脑贯注状态.

  10. HMG-CoA Reductase Inhibition Promotes Neurological Recovery, Peri-Lesional Tissue Remodeling, and Contralesional Pyramidal Tract Plasticity after Focal Cerebral Ischemia

    Science.gov (United States)

    Kilic, Ertugrul; Reitmeir, Raluca; Kilic, Ülkan; Caglayan, Ahmet Burak; Beker, Mustafa Caglar; Kelestemur, Taha; Ethemoglu, Muhsine Sinem; Ozturk, Gurkan; Hermann, Dirk M.

    2014-01-01

    3-Hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors are widely used for secondary stroke prevention. Besides their lipid-lowering activity, pleiotropic effects on neuronal survival, angiogenesis, and neurogenesis have been described. In view of these observations, we were interested whether HMG-CoA reductase inhibition in the post-acute stroke phase promotes neurological recovery, peri-lesional, and contralesional neuronal plasticity. We examined effects of the HMG-CoA reductase inhibitor rosuvastatin (0.2 or 2.0 mg/kg/day i.c.v.), administered starting 3 days after 30 min of middle cerebral artery occlusion for 30 days. Here, we show that rosuvastatin treatment significantly increased the grip strength and motor coordination of animals, promoted exploration behavior, and reduced anxiety. It was associated with structural remodeling of peri-lesional brain tissue, reflected by increased neuronal survival, enhanced capillary density, and reduced striatal and corpus callosum atrophy. Increased sprouting of contralesional pyramidal tract fibers crossing the midline in order to innervate the ipsilesional red nucleus was noticed in rosuvastatin compared with vehicle-treated mice, as shown by anterograde tract tracing experiments. Western blot analysis revealed that the abundance of HMG-CoA reductase was increased in the contralesional hemisphere at 14 and 28 days post-ischemia. Our data support the idea that HMG-CoA reductase inhibition promotes brain remodeling and plasticity far beyond the acute stroke phase, resulting in neurological recovery. PMID:25565957

  11. Using NIR spatial illumination for detection and mapping chromophore changes during cerebral edema

    Science.gov (United States)

    Abookasis, David; Mathews, Marlon S.; Owen, Christopher M.; Binder, Devin K.; Linskey, Mark E.; Frostig, Ron D.; Tromberg, Bruce J.

    2008-02-01

    We used spatially modulated near-infrared (NIR) light to detect and map chromophore changes during cerebral edema in the rat neocortex. Cerebral edema was induced by intraperitoneal injections of free water (35% of body weight). Intracranial pressure (ICP) was measured with an optical fiber based Fabry-Perot interferometer sensor inserted into the parenchyma of the right frontal lobe during water administration. Increase in ICP from a baseline value of 10 cm-water to 145 cm-water was observed. Following induction of cerebral edema, there was a 26+/-1.7% increase in tissue concentration of deoxyhemoglobin and a 47+/-4.7%, 17+/-3% and 37+/-3.7% decrease in oxyhemoglobin, total hemoglobin concentration and cerebral tissue oxygen saturation levels, respectively. To the best of our knowledge, this is the first report describing the use of NIR spatial modulation of light for detecting and mapping changes in tissue concentrations of physiologic chromophores over time in response to cerebral edema.

  12. Research on the effect of remifentanil on cerebral oxygen metabolism and cerebral blood flow of patients with severe brain injury%瑞芬太尼对重型颅脑损伤患者脑氧代谢及脑血流的影响

    Institute of Scientific and Technical Information of China (English)

    王言武

    2014-01-01

    Objective To investigate the effect of remifentanil on cerebral oxygen metabolism and cerebral blood flow of patients with severe brain injury.Methods Retrospective analysis of the clinical data of the 64 cases with severe head injury ad-mitted to our hospital was processed. According to the anesthetic drugs ,64 cases were divided into treatment group and control group ,the control group was treated with fentanyl for anesthesia ,the treatment group was treated with remifentanil for anes-thesia. Cerebral oxygen metabolism and hemodynamic indexes of the two groups before anesthesia and after anesthesia for 10min were compared.Results Before anesthesia ,brain oxygen metabolism and hemodynamic parameters of the two groups were not significantly different ,P>0.05 ;10 min after anesthesia ,CERO2 of the treatment group was significantly higher than that of the control group ,CjvO2 ,Da-jvO2 are significantly lower than that of the control group ,P<0.05;Qmean ,Wv of the treatment group were significantly higher than those of the control group ;DR was significantly lower than that of the control group ,P<0.05.Conclusion Remifentanil anesthesia for patients with severe head injury surgery can improve cerebral oxygen metabolism and cerebral blood flow ,has high security.%目的:探讨瑞芬太尼对重型颅脑损伤患者脑氧代谢的影响。方法回顾性分析我院收治的64例重型颅脑损伤患者的临床资料,根据麻醉药物不同分为治疗组和对照组,对照组采用芬太尼麻醉,治疗组采用瑞芬太尼麻醉,比较2组患者麻醉前、麻醉后10 min时脑氧代谢指标和血流动力学指标。结果麻醉前2组患者的脑氧代谢指标和血流动力学指标比较均无显著性差异(P>0.05);麻醉后10 min治疗组CERO2显著高于对照组,CjvO2、Da-jvO2均显著低于对照组(P<0.05);治疗组Qmean、Wv显著高于对照组,DR显著低于对照组(P<0.05)。结论瑞芬太尼在重型颅脑损

  13. Engineering zonal cartilaginous tissue by modulating oxygen levels and mechanical cues through the depth of infrapatellar fat pad stem cell laden hydrogels.

    Science.gov (United States)

    Luo, Lu; O'Reilly, Adam R; Thorpe, Stephen D; Buckley, Conor T; Kelly, Daniel J

    2016-05-03

    Engineering tissues with a structure and spatial composition mimicking those of native articular cartilage (AC) remains a challenge. This study examined if infrapatellar fat pad-derived stem cells (FPSCs) can be used to engineer cartilage grafts with a bulk composition and a spatial distribution of matrix similar to the native tissue. In an attempt to mimic the oxygen gradients and mechanical environment within AC, FPSC-laden hydrogels (either 2 mm or 4 mm in height) were confined to half of their thickness and/or subjected to dynamic compression (DC). Confining FPSC-laden hydrogels was predicted to accentuate the gradient in oxygen tension through the depth of the constructs (higher in the top and lower in the bottom), leading to enhanced glycosaminoglycan (GAG) and collagen synthesis in 2 mm high tissues. When subjected to DC alone, both GAG and collagen accumulation increased within 2 mm high unconfined constructs. Furthermore, the dynamic modulus of constructs increased from 0.96 MPa to 1.45 MPa following the application of DC. There was no synergistic benefit of coupling confinement and DC on overall levels of matrix accumulation; however in all constructs, irrespective of their height, the combination of these boundary conditions led to the development of engineered tissues that spatially best resembled native AC. The superficial region of these constructs mimicked that of native tissue, staining weakly for GAG, strongly for type II collagen, and in 4 mm high tissues more intensely for proteoglycan 4 (lubricin). This study demonstrated that FPSCs respond to joint-like environmental conditions by producing cartilage tissues mimicking native AC. Copyright © 2016 John Wiley & Sons, Ltd.

  14. Low-oxygen tensions found in Salmonella-infected gut tissue boost Salmonella replication in macrophages by impairing antimicrobial activity and augmenting Salmonella virulence.

    Science.gov (United States)

    Jennewein, Jonas; Matuszak, Jasmin; Walter, Steffi; Felmy, Boas; Gendera, Kathrin; Schatz, Valentin; Nowottny, Monika; Liebsch, Gregor; Hensel, Michael; Hardt, Wolf-Dietrich; Gerlach, Roman G; Jantsch, Jonathan

    2015-12-01

    In Salmonella infection, the Salmonella pathogenicity island-2 (SPI-2)-encoded type three secretion system (T3SS2) is of key importance for systemic disease and survival in host cells. For instance, in the streptomycin-pretreated mouse model SPI-2-dependent Salmonella replication in lamina propria CD11c(-)CXCR1(-) monocytic phagocytes/macrophages (MΦ) is required for the development of colitis. In addition, containment of intracellular Salmonella in the gut critically depends on the antimicrobial effects of the phagocyte NADPH oxidase (PHOX), and possibly type 2 nitric oxide synthase (NOS2). For both antimicrobial enzyme complexes, oxygen is an essential substrate. However, the amount of available oxygen upon enteroinvasive Salmonella infection in the gut tissue and its impact on Salmonella-MΦ interactions was unknown. Therefore, we measured the gut tissue oxygen levels in a model of Salmonella enterocolitis using luminescence two-dimensional in vivo oxygen imaging. We found that gut tissue oxygen levels dropped from ∼78 Torr (∼11% O2) to values of ∼16 Torr (∼2% O2) during infection. Because in vivo virulence of Salmonella depends on the Salmonella survival in MΦ, Salmonella-MΦ interaction was analysed under such low oxygen values. These experiments revealed an increased intracellular replication and survival of wild-type and t3ss2 non-expressing Salmonella. These findings were paralleled by blunted nitric oxide and reactive oxygen species (ROS) production and reduced Salmonella ROS perception. In addition, hypoxia enhanced SPI-2 transcription and translocation of SPI-2-encoded virulence protein. Neither pharmacological blockade of PHOX and NOS2 nor impairment of T3SS2 virulence function alone mimicked the effect of hypoxia on Salmonella replication under normoxic conditions. However, if t3ss2 non-expressing Salmonella were used, hypoxia did not further enhance Salmonella recovery in a PHOX and NOS2-deficient situation. Hence, these data suggest that

  15. Brain tissue aspiration neural tube defect Aspiração de tecido cerebral em casos de defeitos de fechamento do tubo neural

    Directory of Open Access Journals (Sweden)

    Luiz Cesar Peres

    2005-09-01

    Full Text Available The study aimed to find out how frequent is brain tissue aspiration and if brain tissue heterotopia could be found in the lung of human neural tube defect cases. Histological sections of each lobe of both lungs of 22 fetuses and newborn with neural tube defect were immunostained for glial fibrillary acidic protein (GFAP. There were 15 (68.2% females and 7 (31.8% males. Age ranged from 18 to 40 weeks of gestation (mean= 31.8. Ten (45.5% were stillborn, the same newborn, and 2 (9.1% were abortuses. Diagnosis were: craniorrhachischisis (9 cases, 40.9%, anencephaly (8 cases, 36,4%, ruptured occipital encephalocele and rachischisis (2 cases, 9.1% each, and early amniotic band disruption sequence (1 case, 4.5%. Only one case (4.5% exhibited GFAP positive cells inside bronchioles and alveoli admixed to epithelial amniotic squames. No heterotopic tissue was observed in the lung interstitium. We concluded that aspiration of brain tissue from the amniotic fluid in neural tube defect cases may happen but it is infrequent and heterotopia was not observed.O objetivo do estudo foi identificar qual a freqüência de aspiração de tecido cerebral e a existência de heterotopia nos pulmões de casos humanos de defeito de fechamento do tubo neural através da reação imuno-histoquímica para proteína fibrilar glial ácida (GFAP em cortes histológicos de todos os lobos de ambos os pulmões de 22 casos de fetos e neonatos com defeito de fechamento do tubo neural. Havia 15 casos femininos (68,2% e 7 masculinos (31,8%, com idade gestacional variando de 18 a 40 semanas (média= 31,8, sendo natimortos e neomortos 10 (45,5% cada e 2 (9,1% abortos. Os diagnósticos foram: Craniorraquisquise (9 casos, 40,9%, anencefalia (8 casos, 36,4%, encefalocele occipital rota e raquisquise (2 casos, 9,1% e 1 (4,5%caso de seqüência de disruptura amniótica precoce. Somente 1 caso (4,5% apresentou células positivas dentro de bronquíolos e alvéolos em meio a células epiteliais

  16. In vitro study of 3D PLGA/n-HAp/β-TCP composite scaffolds with etched oxygen plasma surface modification in bone tissue engineering

    Science.gov (United States)

    Roh, Hee-Sang; Jung, Sang-Chul; Kook, Min-Suk; Kim, Byung-Hoon

    2016-12-01

    Three-dimensional (3D) scaffolds have many advantageous properties for bone tissue engineering application, due to its controllable properties such as pore size, structural shape and interconnectivity. In this study, effects on oxygen plasma surface modification and adding of nano-hydroxyapatite (n-HAp) and β-tricalcium phosphate (β-TCP) on the 3D PLGA/n-HAp/β-TCP scaffolds for improving preosteoblast cell (MC3T3-E1) adhesion, proliferation and differentiation were investigated. The 3D PLGA/n-HAp/β-TCP scaffolds were fabricated by 3D Bio-Extruder equipment. The 3D scaffolds were prepared with 0°/90° architecture and pore size of approximately 300 μm. In addition 3D scaffolds surface were etched by oxygen plasma to enhance the hydrophilic property and surface roughness. After oxygen plasma treatment, the surface chemistry and morphology were investigated by Fourier transform infrared spectroscopy, scanning electron microscopy, and atomic force microscopy. And also hydrophilic property was measured by contact angle. The MC3T3-E1 cell proliferation and differentiation were investigated by MTT assay and ALP activity. In present work, the 3D PLGA/HAp/beta-TCP composite scaffold with suitable structure for the growth of osteoblast cells was successfully fabricated by 3D rapid prototyping technique. The surface hydrophilicity and roughness of 3D scaffold increased by oxygen plasma treatment had a positive effect on cell adhesion, proliferation, and differentiation. Furthermore, the differentiation of MC3T3-E1 cell was significantly enhanced by adding of n-HAp and β-TCP on 3D PLGA scaffold. As a result, combination of bioceramics and oxygen plasma treatment showed a synergistic effect on biocompatibility of 3D scaffolds. This result confirms that this technique was useful tool for improving the biocompatibility in bone tissue engineering application.

  17. Role of Aquaporin-4 in Cerebral Edema and Stroke

    OpenAIRE

    Zador, Zsolt; Stiver, Shirley; Wang, Vincent; MANLEY, GEOFFREY T.

    2009-01-01

    Cerebral edema plays a central role in the pathophysiology of many diseases of the central nervous system (CNS) including ischemia, trauma, tumors, inflammation, and metabolic disturbances. The formation of cerebral edema results in an increase in tissue water content and brain swelling which, if unchecked, can lead to elevated intracranial pressure (ICP), reduced cerebral blood flow, and ultimately cerebral herniation and death. Despite the clinical significance of cerebral edema, the mechan...

  18. Cerebral blood flow response to functional activation

    DEFF Research Database (Denmark)

    Paulson, Olaf B; Hasselbalch, Steen G; Rostrup, Egill

    2010-01-01

    Cerebral blood flow (CBF) and cerebral metabolic rate are normally coupled, that is an increase in metabolic demand will lead to an increase in flow. However, during functional activation, CBF and glucose metabolism remain coupled as they increase in proportion, whereas oxygen metabolism only...

  19. Head position change is not associated with acute changes in bilateral cerebral oxygenation in stable preterm infants during the first three days of life

    Science.gov (United States)

    Liao, Steve Ming-Che; Rao, Rakesh; Mathur, Amit M.

    2015-01-01

    Objective Several recent intraventricular hemorrhage prevention bundles include midline head positioning to prevent potential disturbances in cerebral hemodynamics. We aimed to study the impact of head position change on regional cerebral saturations (SctO2) in preterm infants (< 30 weeks GA) during the first three days of life. Study Design Bilateral SctO2 was measured by near infrared spectroscopy. The infant's head was turned sequentially to each side from midline (baseline) in thirty-minute intervals while keeping the body supine. Bilateral SctO2 before and after each position change were compared using paired t-test. Results In relatively stable preterm infants (gestational age 26.5±1.7 weeks, birth weight 930±220g; n=20), bilateral SctO2 remained within normal range (71.1% - 75.3%) when the head was turned from midline position to either side. Conclusion Stable preterm infants tolerated brief changes in head position from midline without significant alternation in bilateral SctO2; the impact on critically ill infants needs further evaluation. PMID:25282608

  20. Improved cerebral energetics and ketone body metabolism in db/db mice.

    Science.gov (United States)

    Andersen, Jens V; Christensen, Sofie K; Nissen, Jakob D; Waagepetersen, Helle S

    2017-03-01

    It is becoming evident that type 2 diabetes mellitus is affecting brain energy metabolism. The importance of alternative substrates for the brain in type 2 diabetes mellitus is poorly understood. The aim of this study was to investigate whether ketone bodies are relevant candidates to compensate for cerebral glucose hypometabolism and unravel the functionality of cerebral mitochondria in type 2 diabetes mellitus. Acutely isolated cerebral cortical and hippocampal slices of db/db mice were incubated in media containing [U-(13)C]glucose, [1,2-(13)C]acetate or [U-(13)C]β-hydroxybutyrate and tissue extracts were analysed by mass spectrometry. Oxygen consumption and ATP synthesis of brain mitochondria of db/db mice were assessed by Seahorse XFe96 and luciferin-luciferase assay, respectively. Glucose hypometabolism was observed for both cerebral cortical and hippocampal slices of db/db mice. Significant increased metabolism of [1,2-(13)C]acetate and [U-(13)C]β-hydroxybutyrate was observed for hippocampal slices of db/db mice. Furthermore, brain mitochondria of db/db mice exhibited elevated oxygen consumption and ATP synthesis rate. This study provides evidence of several changes in brain energy metabolism in type 2 diabetes mellitus. The increased hippocampal ketone body utilization and improved mitochondrial function in db/db mice, may act as adaptive mechanisms in order to maintain cerebral energetics during hampered glucose metabolism.

  1. A Prospective Randomized Study of Brain Tissue Oxygen Pressure-Guided Management in Moderate and Severe Traumatic Brain Injury Patients

    Directory of Open Access Journals (Sweden)

    Chien-Min Lin

    2015-01-01

    Full Text Available The purpose of this study was to compare the effect of PbtO2-guided therapy with traditional intracranial pressure- (ICP- guided treatment on the management of cerebral variables, therapeutic interventions, survival rates, and neurological outcomes of moderate and severe traumatic brain injury (TBI patients. From 2009 to 2010, TBI patients with a Glasgow coma scale 20 mmHg, and 27 patients were treated with ICP-guided therapy (ICP 60 mmHg in the neurosurgical intensive care unit (NICU; demographic characteristics were similar across groups. The survival rate in the PbtO2-guided group was also significantly increased at 3 and 6 months after injury. Moreover, there was a significant correlation between the PbtO2 signal and Glasgow outcome scale-extended in patients from 1 to 6 months after injury. This finding demonstrates that therapy directed by PbtO2 monitoring is valuable for the treatment of patients with moderate and severe TBI and that increasing PaO2 to 150 mmHg may be efficacious for preventing cerebral hypoxic events after brain trauma.

  2. 通气程度对颅脑损伤患者脑氧供需平衡的影响%Effect of hyperventilation on cerebral oxygen supply-demand balance in patients with traumatic brain injury

    Institute of Scientific and Technical Information of China (English)

    程明华; 许映娜

    2005-01-01

    BACKGROUND: Inadequate hyperventilation may trigger cerebrovascular contraction and lead to lowered cerebral perfusion and oxygen supply-demand imbalance.OBJECTIVE: To investigate the influence of hyperventilation on oxygen saturation in the internal jugular vein, difference in oxygen and lactic acid contents between the cerebral arteries and veins in patients with serious traumatic brain injury.DESIGN: Case analysis.SETTING: Department of Anesthesiology, First Hospital Affiliated to Shantou University.PARTICIPANTS: Sixteen patients who received emergency operations in the First Hospital Affiliated to Shantou University between January and July 2002.METHODS: Patients with traumatic brain injury underwent operation under general anesthesia, and the PaCO2 was maintained at 30 mm Hg for 15 minutes by regulating the respiration rate, followed by decrease to 25 mm Hg, maintained for 15 minutes before restoration to 30 mm Hg for 15 minutes. The fractional concentration of inspired oxygen was adjusted to maintain blood PaO2 at around 100-150 mm Hg, and the blood sample was collected from the artery and internal jugular vein 15 minutes after adjustment of PaCO2 for blood gas analysis. The PaO2 was then increased to 200-250 mm Hg by increasing the fractional concentration of inspired oxygen, and the PaCO2 was adjusted from 30 to 25 and then back to 30 mm Hg in the described manner, and the oxygen saturation in the internal jugular vein, difference in oxygen and lactic acid contents between the arteries and the veins were measured.MAIN OUTCOME MEASURES: Influence of blood PaO2 and PaCO2 on oxygen saturation in the internal jugular vein, difference in oxygen and lactic acid contents between the arteries and the veins.RESULTS: Sixteen patients met the diagnostic criteria and completed data collection. The arterial PaCO2 decreased from 30 to 25 mm Hg when arterial blood oxygen pressure increased from 100-150 to 200-250 mm Hg, which leads to obvious decrease of oxygen saturation

  3. Tracking of In-111-labeled human umbilical tissue-derived cells (hUTC in a rat model of cerebral ischemia using SPECT imaging

    Directory of Open Access Journals (Sweden)

    Arbab Ali S

    2012-12-01

    Full Text Available Abstract Background In order to increase understanding of how infused cells work, it becomes important to track their initial movement, localization, and engraftment efficiency following transplantation. However, the available in vivo cell tracking techniques are suboptimal. The study objective was to determine the biodistribution of intravenously administered Indium-111 (In-111 oxine labeled human umbilical tissue-derived cells (hUTC in a rat model of transient middle cerebral occlusion (tMCAo using single photon emission computed tomography (SPECT. Methods Rats received 3 million In-111 labeled hUTC (i.v. 48 hrs after tMCAo. Following the administration of either hUTC or equivalent dose of In-111-oxine (18.5 MBq, animals underwent SPECT imaging on days 0, 1, and 3. Radioactivity in various organs as well as in the stroke area and contralateral hemisphere was determined, decay corrected and normalized to the total (whole body including head radioactivity on day 0. Immunohistochemical analysis was also performed to confirm the beneficial effects of hUTC on vascular and synaptic density, and apoptosis. Results Most of the radioactivity (43.36±23.07% on day 0 trafficked to the lungs immediately following IV administration of In-111 labeled hUTC (day 0 and decreased drastically to 8.81±7.75 and 4.01±4.52% on days 1 and 3 post-injection, respectively. In contrast, radioactivity measured in the lung of animals that received In-111-oxine alone remained relatively unchanged from day 0 to day 1 (18.38±5.45% at day 0 to 12.59±5.94% and decreased to 8.34±4.25% on day 3. Significantly higher radioactivity was observed in stroke areas of animals that received In-111 labeled hUTC indicating the presence of cells at the site of injury representing approximately 1% of total administered dose. In addition, there was significant increase in vascular and synaptophysin immunoreactivity in stroke areas of rats that received In-111 labeled h

  4. Oxygen Saturation Determined from Deep Muscle, Not Thenar Tissue, Is an Early Indicator of Central Hypovolemia in Humans

    Science.gov (United States)

    2008-01-01

    21). Removal of spectral interference from skin pigmentation and fat is critical to deter- mining absolute chemical concentrations from muscle...from skin pigment and fat is removed, the spectra describe capillary absorbance from the muscle alone. A Taylor series expansion attenuation method (22...oxygen saturation (Smo2) is defined by Equation 1: SmO2 C HbO2 MbO2 C HbO2 MbO2 C Hb Mb [1] where CHbO2 MbO2 is the oxygenated heme concentration

  5. Detection of cerebral autoregulation by near-infrared spectroscopy in neonates: performance analysis of measurement methods

    Science.gov (United States)

    Caicedo, Alexander; Naulaers, Gunnar; Lemmers, Petra; van Bel, Frank; Wolf, Martin; Van Huffel, Sabine

    2012-11-01

    Cerebral Autoregulation, in clinical practice, is assessed by means of correlation or coherence analysis between mean arterial blood pressure (MABP) and cerebral blood flow (CBF). However, even though there is evidence linking cerebral autoregulation assessment with clinical outcome in preterm infants, available methods lack precision for clinical use. Classical methods, used for cerebral autoregulation, are influenced by the choice of parameters such as the length of the epoch under analysis and the choice of suitable frequency bands. The influence of these parameters, in the derived measurements for cerebral autoregulation, has not yet been evaluated. In this study, cerebral autoregulation was assessed using correlation, coherence, a modified version of coherence and transfer function gain, and phase. The influence of the extra-parameters on the final scores was evaluated by means of sensitivity analysis. The methods were applied to a database of 18 neonates with measurements of MABP and tissue oxygenation index (TOI). TOI reflects changes in CBF and was measured by means of near-infrared spectroscopy.

  6. Wavelet coherence analysis of dynamic cerebral autoregulation in neonatal hypoxic–ischemic encephalopathy

    Directory of Open Access Journals (Sweden)

    Fenghua Tian

    2016-01-01

    Full Text Available Cerebral autoregulation represents the physiological mechanisms that keep brain perfusion relatively constant in the face of changes in blood pressure and thus plays an essential role in normal brain function. This study assessed cerebral autoregulation in nine newborns with moderate-to-severe hypoxic–ischemic encephalopathy (HIE. These neonates received hypothermic therapy during the first 72 h of life while mean arterial pressure (MAP and cerebral tissue oxygenation saturation (SctO2 were continuously recorded. Wavelet coherence analysis, which is a time-frequency domain approach, was used to characterize the dynamic relationship between spontaneous oscillations in MAP and SctO2. Wavelet-based metrics of phase, coherence and gain were derived for quantitative evaluation of cerebral autoregulation. We found cerebral autoregulation in neonates with HIE was time-scale-dependent in nature. Specifically, the spontaneous changes in MAP and SctO2 had in-phase coherence at time scales of less than 80 min (<0.0002 Hz in frequency, whereas they showed anti-phase coherence at time scales of around 2.5 h (~0.0001 Hz in frequency. Both the in-phase and anti-phase coherence appeared to be related to worse clinical outcomes. These findings suggest the potential clinical use of wavelet coherence analysis to assess dynamic cerebral autoregulation in neonatal HIE during hypothermia.

  7. Existence of vimentin and GFAP protein expressions as a result of 2-Methoxyethanol administration in cerebral cortex tissue of Swiss Webster mice (Mus musculus): an immunohistochemical analysis.

    Science.gov (United States)

    Irnidayanti, Yulia

    2014-07-01

    Une of the plastic-based materials widely used in the plastics industry in various countries is ester phthalate. This compound will be oxidized in the body into 2-methoxyethanol (2-ME). The effect of 2-ME on human health and environment depends on the number, duration and the frequency of exposure. Recently, the incidence of brain damage tends to increase. In the last decade, it has been widely reported the negative effects of chemical pollutants to the environment. The aim of this study were to know the existence of the expression of Vimentin and GFAP proteins caused by 2-ME on the histological structure of the cerebral cortex of mice fetal during the prenatal period on gestation day 14 (GD 14) and day 18 (GD 18). The 2-ME compound was injected intraperitoneally with a dose of 7.5 mmol kg(-1) of body weight at GD-10. The result showed that there is a change in existence Vimentin protein in the cerebral cortex fetal of treated mice at GD 14, which is very conspicuous. Meanwhile, a change in existence of GFAP protein in cerebral cortex fetal of treated mice at GD 14, have relatively no difference from controls and no impact on histological structure changes of the cerebral corteks at GD 14. The change in existence of Vimentin protein in the cerebral cortex fetal of treated mice at GD 14 have an impact on histological structure of the cerebral cortex of mice treated at GD 18. It is believed that the impact is due to the effects of 2-methoxyethanol.

  8. Photochemical studies of a fluorescent chlorophyll catabolite--source of bright blue fluorescence in plant tissue and efficient sensitizer of singlet oxygen.

    Science.gov (United States)

    Jockusch, Steffen; Turro, Nicholas J; Banala, Srinivas; Kräutler, Bernhard

    2014-02-01

    Fluorescent chlorophyll catabolites (FCCs) are fleeting intermediates of chlorophyll breakdown, which is seen as an enzyme controlled detoxification process of the chlorophylls in plants. However, some plants accumulate large amounts of persistent FCCs, such as in senescent leaves and in peels of yellow bananas. The photophysical properties of such a persistent FCC (Me-sFCC) were investigated in detail. FCCs absorb in the near UV spectral region and show blue fluorescence (max at 437 nm). The Me-sFCC fluorescence had a quantum yield of 0.21 (lifetime 1.6 ns). Photoexcited Me-sFCC intersystem crosses into the triplet state (quantum yield 0.6) and generates efficiently singlet oxygen (quantum yield 0.59). The efficient generation of singlet oxygen makes fluorescent chlorophyll catabolites phototoxic, but might also be useful as a (stress) signal and for defense of the plant tissue against infection by pathogens.

  9. Protective Effect of Extract of Folium Ginkgo on Repeated Cerebral Ischemia-Reperfusion Injury

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective: To study the protective effect of extract of Folium Ginkgo (FGE) on repeated cerebral ischemia-reperfusion injury. Methods: The model in waking mice induced by repeated cerebral ischemia-reperfusion were used in the experiment to observe the effect of FGE on behavior, oxygen free radical metabolism and prostaglandin E2 (PGE2) content by step-through experiment, diving stand and colorimetric method. Results: FGE could obviously improve the learning ability and memory of model animals, and could lower obviously the content of malonyldialdehyde, nitric oxide and PGE2, restore the lowered activity of superoxide dismutase and catalase in cerebral tissue. Conclusion: FGE has highly protective effect against repeated ischemia-reperfusion injury, the mechanism might be related with its action on anti-lipid oxidatin, improve the activity of antioxidase and inhibit the producing of PGE2.

  10. Unchanged cerebral blood flow and oxidative metabolism after acclimatization to high altitude

    DEFF Research Database (Denmark)

    Møller, Kirsten; Paulson, Olaf B; Hornbein, Thomas F.

    2002-01-01

    . At high altitude at rest, arterial carbon dioxide tension, oxygen saturation, and oxygen tension were significantly reduced, and arterial oxygen content was increased because of an increase in hemoglobin concentration. Global cerebral blood flow was similar in the four conditions. Cerebral oxygen delivery...

  11. The role of tissue oxygen tension in the control of local blood flow in the microcirculation of skeletal muscles

    DEFF Research Database (Denmark)

    Ngo, Thuc Anh

    2010-01-01

    /or NO in response to hypoxia, which acts on the vascular wall causing vasodilatation. In cremaster arterioles devoid of RBCs, achieved by buffer perfusion via a cannula in the abdominal aorta of the animals, the cremaster arterioles showed the same degree of dilatation and constriction to low and high oxygen...

  12. Effects of high-frequency oscillatory ventilation and conventional mechanical ventilation on oxygen metabolism and tissue perfusion in sheep models of acute respiratory distress syndrome

    Institute of Scientific and Technical Information of China (English)

    Liu Songqiao; Huang Yingzi; Wang Maohua; Chen Qiuhua; Liu Ling; Xie Jianfeng; Tan Li

    2014-01-01

    Background High-frequency oscillatory ventilation (HFOV) allows for small tidal volumes at mean airway pressures (mPaw) above that of conventional mechanical ventilation (CMV),but the effect of HFOV on hemodynamics,oxygen metabolism,and tissue perfusion in acute respiratory distress syndrome (ARDS) remains unclear.We investigated the effects of HFOV and CMV in sheep models with ARDS.Methods After inducing ARDS by repeated lavage,twelve adult sheep were randomly divided into a HFOV or CMV group.After stabilization,standard lung recruitments (40 cmH2O × 40 seconds) were performed.The optimal mPaw or positive end-expiratory pressure was obtained by lung recruitment and decremental positive end-expiratory pressure titration.The animals were then ventilated for 4 hours.The hemodynamics,tissue perfusion (superior mesenteric artery blood flow,pHi,and Pg-aCO2),oxygen metabolism and respiratory mechanics were examined at baseline before saline lavage,in the ARDS model,after model stabilization,and during hourly mechanical ventilation for up to 4 hours.A two-way repeated measures analysis of variance was applied to evaluate differences between the groups.Results The titrated mPaw was higher and the tidal volumes lower in the HFOV group than the positive end-expiratory pressure in the CMV group.There was no significant difference in hemodynamic parameters between the HFOV and CMV groups.There was no difference in the mean alveolar pressure between the two groups.After lung recruitment,both groups showed an improvement in the oxygenation,oxygen delivery,and DO2.Lactate levels increased in both groups after inducing the ARDS model.Compared with the CMV group,the superior mesenteric artery blood flow and pHi were significantly higher in the HFOV group,but the Pg-aCO2 decreased in the HFOV group.Conclusion Compared with CMV,HFOV with optimal mPaw has no significant side effect on hemodynamics or oxygen metabolism,and increases gastric tissue blood perfusion.

  13. Early biomarkers of brain injury and cerebral hypo- and hyperoxia in the SafeBoosC II trial

    DEFF Research Database (Denmark)

    Plomgaard, Anne M; Alderliesten, Thomas; Austin, Topun

    2017-01-01

    BACKGROUND: The randomized clinical trial, SafeBoosC II, examined the effect of monitoring of cerebral oxygenation by near-infrared spectroscopy combined with a guideline on treatment when cerebral oxygenation was out of the target range. Data on cerebral oxygenation was collected in both the int...

  14. Which blood oxygen can sensitively indicate shock severity?

    Science.gov (United States)

    Pan, Boan; Li, Kai; Gao, Yuan; Ruan, Zhengshang; Li, Ting

    2016-03-01

    Clinical shock-monitoring mainly depends on measuring oxygen saturations from SVC blood samples invasively. The golden standard indicator is the central internal jugular vein oxygenation (SjvO2). Using near-infrared spectroscopy (NIRS) also can monitor shock in some papers published, but there is no discussion about which oxygen saturation (cerebral venous oxygen saturation, ScvO2; tissue oxygen saturation of internal jugular area; tissue oxygen saturation of extremities areas) can monitor shock patient more sensitively and accurately. The purpose of this paper is to examine which one is most effective. In order to discuss the problem, we continuously detected 56 critical patients who may be into shock state using NIRS oximeter at prefrontal, internal jugular vein area and forearm, and chose 24 patients who were into shock and then out of shock from the 56 critical patients. Combined with the patients' condition, the pulse oxygen saturation is most sensitively to monitoring shock than the others, and the internal jugular vein area oxygen saturation is most effective.

  15. Non-invasive optical measurement of cerebral metabolism and hemodynamics in infants.

    Science.gov (United States)

    Lin, Pei-Yi; Roche-Labarbe, Nadege; Dehaes, Mathieu; Carp, Stefan; Fenoglio, Angela; Barbieri, Beniamino; Hagan, Katherine; Grant, P Ellen; Franceschini, Maria Angela

    2013-03-14

    Perinatal brain injury remains a significant cause of infant mortality and morbidity, but there is not yet an effective bedside tool that can accurately screen for brain injury, monitor injury evolution, or assess response to therapy. The energy used by neurons is derived largely from tissue oxidative metabolism, and neural hyperactivity and cell death are reflected by corresponding changes in cerebral oxygen metabolism (CMRO₂). Thus, measures of CMRO₂ are reflective of neuronal viability and provide critical diagnostic information, making CMRO₂ an ideal target for bedside measurement of brain health. Brain-imaging techniques such as positron emission tomography (PET) and single-photon emission computed tomography (SPECT) yield measures of cerebral glucose and oxygen metabolism, but these techniques require the administration of radionucleotides, so they are used in only the most acute cases. Continuous-wave near-infrared spectroscopy (CWNIRS) provides non-invasive and non-ionizing radiation measures of hemoglobin oxygen saturation (SO₂) as a surrogate for cerebral oxygen consumption. However, SO₂ is less than ideal as a surrogate for cerebral oxygen metabolism as it is influenced by both oxygen delivery and consumption. Furthermore, measurements of SO₂ are not sensitive enough to detect brain injury hours after the insult, because oxygen consumption and delivery reach equilibrium after acute transients. We investigated the possibility of using more sophisticated NIRS optical methods to quantify cerebral oxygen metabolism at the bedside in healthy and brain-injured newborns. More specifically, we combined the frequency-domain NIRS (FDNIRS) measure of SO2 with the diffuse correlation spectroscopy (DCS) measure of blood flow index (CBFi) to yield an index of CMRO₂ (CMRO₂i). With the combined FDNIRS/DCS system we are able to quantify cerebral metabolism and hemodynamics. This represents an improvement over CWNIRS for detecting brain health, brain

  16. Medida da diferença artério-venosa de oxigênio na monitorização de pacientes com hemorragia subaracnóidea por aneurisma cerebral Measurement of arteriovenous oxygen difference in the monitoring of patients with subarachnoid haemorrhage due to cerebral aneurysm

    Directory of Open Access Journals (Sweden)

    Ronaldo Sérgio Santana Pereira

    1997-01-01

    Full Text Available A diferença artério-venosa de oxigênio (DAVO2, pelo fato de estar relacionada com o metabolismo cerebral, reflete alterações que ocorrem em determinadas situações patológicas, entre elas as causadas pela hemorragia subaracnóidea espontânea (HSAE. Com a finalidade de avaliar a relação entre alterações na DAVO2 com o quadro clínico e a evolução de pacientes com HSAE, devido à ruptura de aneurisma cerebral, este método foi utilizado em 30 pacientes portadores desta patologia, admitidos na Unidade de Neurocirurgia do HBDF. A HSAE foi confirmada por CT de crânio em 17 pacientes e por punção lombar em 13. Dezoito pacientes foram admitidos com Hunt & Hess (H&H I ou II, sete com H&H III e cinco com H&H IV ou V. A medida da DAVO2 baseou-se na equação de Fick e os resultados clínicos foram avaliados pela escala de seqüelas de Glasgow. Dezenove pacientes apresentaram DAVO2 normais (inicialmente e durante a evolução, sendo que três faleceram; cinco tiveram valores de DAVO2 sempre baixos e três faleceram; os restantes seis pacientes tiveram valores da DAVO2 sempre elevados e dois faleceram. Os pacientes com DAVO2 normais tiveram melhor evolução clínica e índice de mortalidade menor, quando comparados com os pacientes com valores anormais da DAVO2 (pThe arterious venous oxygen difference (AVDO2 due to the close relationship with cerebral metabolic rate of oxygen and cerebral blood flow shows metabolic alterations that occur in some pathological situations in the brain including subarachnoid haemorrhage. The AVDO2 was calculated by the Fick equation and the results evaluated by the Glasgow outcome scale. Measurements of arteriojugular oxygen difference were carried out in 30 patients with subarachnoid haemorrhage due to rupture of intracranial aneurysms, as an attempt to monitor the relationship between changes in AVDO2, clinical picture, and evolution of the patients. The subarachnoid haemorrhage was diagnosed by CT scan in

  17. Observation of postoperative rehabilitation efficacy of hyperbaric oxygen on brain tumors, cerebral aneurysms%高压氧对脑肿瘤、脑动脉瘤术后康复疗效的观察

    Institute of Scientific and Technical Information of China (English)

    江坤

    2014-01-01

    Objective To investigate the clinical effect of hyperbaric oxygen (HBO) in the treatment of brain tumors and cerebral aneurysms. Methods 200 patients with brain tumors or cerebral aneurysms in our hospital from 2009 December to 2013 December were selected, they were divided into two groups according to the different treatments. 100 cases with brain tumors or cerebral aneurysms were as the observation group that treated by HBO. 100 cases with similar disease were as the control group that treated without HBO. The two groups were both given conventional drug treatment .Checked cerebral vasospasm (CVS) by head color Doppler ultrasound, evaluated clinical recovery by neurological function and activities of daily living assessment, the clinical efficacy were compared and analyzed. Results The NF score and Barthel score of the two groups had no significant difference before the treatment (P>0.05);the NF score and Barthel score of the two groups had significant difference after the treatment (P 0.05), Middle cerebral artery flow velocity and CVS of the two groups had significant difference after the treatment(P<0.05). Conclusion HBO comprehensive treatment effect is remarkable, it can reduce neurological deficits, improve the quality of patients' life, it should be introduced.%目的:探讨高压氧(HBO)治疗脑肿瘤、脑动脉瘤术后康复的临床疗效。方法选取我院2009年12月~2013年12月收治的脑肿瘤、脑动脉瘤术后患者200例,根据治疗方法不同分为两组,将100例HBO治疗的脑肿瘤、脑动脉瘤术后患者设为观察组,将病情相似未作HBO治疗的100例患者设为对照组,两组均常规药物治疗。采用头颅彩色多普勒超声检查患者脑血管痉挛(CVS)情况,并采用神经功能缺损评分和日常生活活动能力评定评判患者临床恢复情况,并对临床疗效进行对比分析。结果两组患者治疗前NF评分和Barthel评分比较差异无统计学意义(P>0.05

  18. Vasoespasmo cerebral

    Directory of Open Access Journals (Sweden)

    Antonio A. F. de Salles

    1987-09-01

    Full Text Available Vasoespasmo cerebral ocorre em patologias como enxaqueca, hemorragia subaracnóidea, trauma de crânio, após isquemia e/ou hipoxia. A fisiopatologia do vasoespasmo cerebral nestas patologias não está completamente desvendada. Neste artigo são analisados os fatores neuroquímicos e morfológicos responsáveis pelo controle circulatório cerebral. As alterações circulatórias que seguem a hemorragia subaracnóidea são utilizadas como exemplo. Conclui-se que fatores bioquímicos, fisiológicos e morfológicos são responsáveis pelas manifestações vasculares que ocorrem após a hemorragia subaracnóidea. Alternativas de tratamento do vasoespasmo cerebral são discutidas.

  19. Intra-operative tissue oxygen tension is increased by local insufflation of humidified-warm CO2 during open abdominal surgery in a rat model.

    Directory of Open Access Journals (Sweden)

    Jean K Marshall

    Full Text Available Maintenance of high tissue oxygenation (PtO2 is recommended during surgery because PtO2 is highly predictive of surgical site infection and colonic anastomotic leakage. However, surgical site perfusion is often sub-optimal, creating an obstructive hurdle for traditional, systemically applied therapies to maintain or increase surgical site PtO2. This research tested the hypothesis that insufflation of humidified-warm CO2 into the abdominal cavity would increase sub-peritoneal PtO2 during open abdominal surgery.15 Wistar rats underwent laparotomy under general anesthesia. Three sets of randomized cross-over experiments were conducted in which the abdominal cavity was subjected to alternating exposure to 1 humidified-warm CO2 & ambient air; 2 humidified-warm CO2 & dry-cold CO2; and 3 dry-cold CO2 & ambient air. Sub-peritoneal PtO2 and tissue temperature were measured with a polarographic oxygen probe.Upon insufflation of humidified-warm CO2, PtO2 increased by 29.8 mmHg (SD 13.3; p<0.001, or 96.6% (SD 51.9, and tissue temperature by 3.0°C (SD 1.7 p<0.001, in comparison with exposure to ambient air. Smaller, but significant, increases in PtO2 were seen in experiments 2 and 3. Tissue temperature decreased upon exposure to dry-cold CO2 compared with ambient air (-1.4°C, SD 0.5, p = 0.001.In a rat model, insufflation of humidified-warm CO2 into the abdominal cavity during open abdominal surgery causes an immediate and potentially clinically significant increase in PtO2. The effect is an additive result of the delivery of CO2 and avoidance of evaporative cooling via the delivery of the CO2 gas humidified at body temperature.

  20. 高压氧辅助药物治疗动脉粥样硬化脑血管痉挛随机对照研究%Effect of hyperbaric oxygen combined with drug on patients with atherosclerotic cerebral vasospasm

    Institute of Scientific and Technical Information of China (English)

    辜忠灵

    2014-01-01

    目的:分析高压氧辅助药物治疗动脉粥样硬化脑血管痉挛的效果。方法选择在本院接受住院治疗的动脉粥样硬化脑血管痉挛患者作为研究对象,分别给予单纯药物治疗及高压氧辅助药物治疗,比较有效率、血液学指标、基底动脉管径及NO、NOS、Ca2+含量等。结果观察组有效率(97.06%)、基底动脉管径[(4.98±1.35)mm]、NO [(59.43±11.48)μmol/L]、NOS[(98.43±14.38)kU/L]均明显高于对照组;胆固醇[(3.12±0.72)mmol/L]、甘油三酯[(1.27±0.41)mmol/L]、血小板计数[(112.74±13.36)×109/L]、血黏度[(1.21±0.37) mPa · s]、[Ca2+(17.07±1.65)g/μmol]明显低于对照组( P<0.05)。结论高压氧辅助药物可有效提高动脉粥样硬化脑血管痉挛患者的临床疗效,优化血液学指标,升高基底动脉管径、NO及NOS ,减少Ca2+含量,具有积极的临床意义。%Objective To analyze the efficacy of hyperbaric oxygen combined with drug on patients with atherosclerotic cerebral vasospasm. Methods Patients with atherosclerotic cerebral vasospasm admitted to our hospital were chosen as re-search subjects ,and divided into observation group and control group. The control group was given drug therapy alone and the observation group was given hyperbaric oxygen combined with drug therapy. The efficiency of treatment ,hematological index , and basilar artery diameter ,NO ,NOS ,Ca2+ level of the two groups were compared. Results The efficacy rate (97.06% ) ,bas-al artery diameter(4.98 ± 4.98) mm ,NO(59.43 ± 11.48)μmol/L ,NO (98.43 ± 14.38) kU/L of observation group were sig-nificantly higher than those of the control group ;Cholesterol(3.12 ± 0.72) mmol/L ,triglycerides(1.27 ± 0.41) mmol/L , platelet count(112.74 ± 13.36)109/L ,blood viscosity(1.21 ± 0.37 )mPa · s ,Ca2+ (17.07 ± 1.65) g/μmol were significantly lower than those of the control group(P<0.05).Conclusion Hyperbaric oxygen

  1. Oxygen consumption and blood flow coupling in human motor cortex during intense finger tapping

    DEFF Research Database (Denmark)

    Seyedi Vafaee, Manouchehr; Vang, Kim; Bergersen, Linda H

    2012-01-01

    Rates of cerebral blood flow (CBF) and glucose consumption (CMR(glc)) rise in cerebral cortex during continuous stimulation, while the oxygen-glucose index (OGI) declines as an index of mismatched coupling of oxygen consumption (cerebral metabolic rate of oxygen-CMRO(2)) to CBF and CMR...

  2. Wearable wireless cerebral oximeter (Conference Presentation)

    Science.gov (United States)

    Zhang, Xin; Jiang, Tianzi

    2016-03-01

    Cerebral oximeters measure continuous cerebral oxygen saturation using near-infrared spectroscopy (NIRS) technology noninvasively. It has been involved into operating room setting to monitor oxygenation within patient's brain when surgeons are concerned that a patient's levels might drop. Recently, cerebral oxygen saturation has also been related with chronic cerebral vascular insufficiency (CCVI). Patients with CCVI would be benefited if there would be a wearable system to measure their cerebral oxygen saturation in need. However, there has yet to be a wearable wireless cerebral oximeter to measure the saturation in 24 hours. So we proposed to develop the wearable wireless cerebral oximeter. The mechanism of the system follows the NIRS technology. Emitted light at wavelengths of 740nm and 860nm are sent from the light source penetrating the skull and cerebrum, and the light detector(s) receives the light not absorbed during the light pathway through the skull and cerebrum. The amount of oxygen absorbed within the brain is the difference between the amount of light sent out and received by the probe, which can be used to calculate the percentage of oxygen saturation. In the system, it has one source and four detectors. The source, located in the middle of forehead, can emit two near infrared light, 740nm and 860nm. Two detectors are arranged in one side in 2 centimeters and 3 centimeters from the source. Their measurements are used to calculate the saturation in the cerebral cortex. The system has included the rechargeable lithium battery and Bluetooth smart wireless micro-computer unit.

  3. Effects of Acupuncture on mRNA Levels of Apoptotic Factors in Perihematomal Brain Tissue During the Acute Phase of Cerebral Hemorrhage.

    Science.gov (United States)

    Li, Zuowei; Zheng, Xiaonan; Li, Ping; Itoua, Eudes Saturnin Régis; Moukassa, Donatien; Ndinga Andely, Françoise

    2017-03-30

    BACKGROUND To explore the time-dependent effects of acupuncture on mRNA levels of the apoptotic factors BCL-2 and BAX in a rat cerebral hemorrhage model, slow injection of autologous blood to the caudate nucleus was used to generate the cerebral hemorrhage model. MATERIAL AND METHODS A sham surgery control group, groups with acupuncture applied 3, 9, 24, and 48 hours after model induction, and time-matched model-only control groups were used. In situ hybridization was used to detect BCL-2 and BAX mRNA expression, and semi-quantitative RT-PCR was used to measure the expression. RESULTS The number of BCL-2 and BAX mRNA-positive cells significantly increased during the acute phase of cerebral hemorrhage. BCL-2 mRNA was significantly upregulated in acupuncture groups compared to other groups, whereas BAX mRNA levels in the acupuncture groups were lower in the other groups, except for the sham surgery group. Additionally, earlier acupuncture intervention was associated with a lower ratio of expression between the two genes. Changes in BCL-2 and BAX mRNA expression were consistent with changes in the number of cells positive for BCL-2 and BAX mRNA; however, the change in the expression ratio was consistent with the change in the number of cells positive for BCL-2 mRNA, but opposite to the change in the number of cells positive for BAX mRNA. CONCLUSIONS Acupuncture ameliorated changes in expression of apoptotic factors in the brain induced by acute cerebral hemorrhage and may thus protect the brain, with greater efficacy when the delay before acupuncture was minimized.

  4. Effects of Acupuncture on mRNA Levels of Apoptotic Factors in Perihematomal Brain Tissue During the Acute Phase of Cerebral Hemorrhage

    Science.gov (United States)

    Li, Zuowei; Zheng, Xiaonan; Li, Ping; Itoua, Eudes Saturnin Régis; Moukassa, Donatien; Andely, Françoise Ndinga

    2017-01-01

    Background To explore the time-dependent effects of acupuncture on mRNA levels of the apoptotic factors BCL-2 and BAX in a rat cerebral hemorrhage model, slow injection of autologous blood to the caudate nucleus was used to generate the cerebral hemorrhage model. Material/Methods A sham surgery control group, groups with acupuncture applied 3, 9, 24, and 48 hours after model induction, and time-matched model-only control groups were used. In situ hybridization was used to detect BCL-2 and BAX mRNA expression, and semi-quantitative RT-PCR was used to measure the expression. Results The number of BCL-2 and BAX mRNA-positive cells significantly increased during the acute phase of cerebral hemorrhage. BCL-2 mRNA was significantly upregulated in acupuncture groups compared to other groups, whereas BAX mRNA levels in the acupuncture groups were lower in the other groups, except for the sham surgery group. Additionally, earlier acupuncture intervention was associated with a lower ratio of expression between the two genes. Changes in BCL-2 and BAX mRNA expression were consistent with changes in the number of cells positive for BCL-2 and BAX mRNA; however, the change in the expression ratio was consistent with the change in the number of cells positive for BCL-2 mRNA, but opposite to the change in the number of cells positive for BAX mRNA. Conclusions Acupuncture ameliorated changes in expression of apoptotic factors in the brain induced by acute cerebral hemorrhage and may thus protect the brain, with greater efficacy when the delay before acupuncture was minimized. PMID:28357997

  5. Effects of Hyperoxia on Brain Tissue Oxygen Tension in Non-Sedated, Non- Anesthetized Arctic Ground Squirrels: An Animal Model of Hyperoxic Stress

    Directory of Open Access Journals (Sweden)

    Y. Ma

    2011-01-01

    Full Text Available Arctic Ground Squirrels (AGS are classic hibernators known for their tolerance to hypoxia. AGS have been studied as a model of hypoxia with potential as a medical research model. Problem statement: Their unique resistance to the stressors of low oxygen led us to hypothesize that AGS might also be adaptable to hyperoxia. Approach: This study examined the physiological pattern associated with hyperoxia in response to brain tissue oxygen partial pressure (PtO2, brain temperature (Tbrain, global oxygen consumption (VO2 and respiratory frequency (fR using non-sedated and nonanesthetized Arctic Ground Squirrels (AGS and rats. Results: We found that 1 100% inspired oxygen (FiO2 increased the baseline values of brain PtO2 significantly in both summer euthermic AGS (24.4 ± 3.6-87.3 ± 3.6 mmHg, n=6 and in rats (18.2 ± 5.2-73.3 ± 5.2 mmHg, n = 3; PtO2 was significantly higher in AGS than in rats during hyperoxic exposure; 2 hyperoxic exposure had no effect on brain temperature in either AGS or rats, with the brain temperatures maintaining constancy before, during and after 100% O2 exposure; 3 systemic metabolic rates increased significantly during hyperoxic exposure in both euthermic AGS and rats; moreover, VO2 were significantly lower in AGS than in rats during hyperoxic exposure; 4 the respiratory rates for rats were maintained before, during and after 100% O2 exposure, while the respiratory responding patterns to hyperoxic exposure changed after exposure in AGS. AGS fR was significantly lower after hyperoxic exposure than before the exposure. Conclusion: These results suggest that hyperoxic ventilation induced PtO2 and VO2 differences between AGS and rats and led to altered respiratory patterns between these species. AGS and the rat serves as an excellent comparative model for hypoxic and hyperoxic stress studies of the brain.

  6. The Effect of Active versus Passive Recovery Periods during High Intensity Intermittent Exercise on Local Tissue Oxygenation in 18 – 30 Year Old Sedentary Men

    Science.gov (United States)

    Kerhervé, Hugo A.; Askew, Christopher D.; Solomon, Colin

    2016-01-01

    Purpose High intensity interval training (HIIT) has been proposed as a time-efficient format of exercise to reduce the chronic disease burden associated with sedentary behaviour. Changes in oxygen utilisation at the local tissue level during an acute session of HIIT could be the primary stimulus for the health benefits associated with this format of exercise. The recovery periods of HIIT effect the physiological responses that occur during the session. It was hypothesised that in sedentary individuals, local and systemic oxygen utilisation would be higher during HIIT interspersed with active recovery periods, when compared to passive recovery periods. Methods Twelve sedentary males (mean ± SD; age 23 ± 3 yr) completed three conditions on a cycle ergometer: 1) HIIT with passive recovery periods between four bouts (HIITPASS) 2) HIIT with active recovery periods between four bouts (HIITACT) 3) HIITACT with four HIIT bouts replaced with passive periods (REC). Deoxygenated haemoglobin (HHb) in the vastus lateralis (VL) and gastrocnemius (GN) muscles and the pre-frontal cortex (FH), oxygen consumption (VO2), power output and heart rate (HR) were measured continuously during the three conditions. Results There was a significant increase in HHb at VL during bouts 2 (p = 0.017), 3 (p = 0.035) and 4 (p = 0.035) in HIITACT, compared to HIITPASS. Mean power output was significantly lower in HIITACT, compared to HIITPASS (p < 0.001). There was a significant main effect for site in both HIITPASS (p = 0.029) and HIITACT (p = 0.005). There were no significant differences in VO2 and HR between HIITPASS and HIITACT. Conclusions The increase in HHb at VL and the lower mean power output during HIITACT could indicate that a higher level of deoxygenation contributes to decreased mechanical power in sedentary participants. The significant differences in HHb between sites indicates the specificity of oxygen utilisation. PMID:27677081

  7. The coupling of cerebral blood flow and oxygen metabolism with brain activation is similar for simple and complex stimuli in human primary visual cortex.

    Science.gov (United States)

    Griffeth, Valerie E M; Simon, Aaron B; Buxton, Richard B

    2015-01-01

    Quantitative functional MRI (fMRI) experiments to measure blood flow and oxygen metabolism coupling in the brain typically rely on simple repetitive stimuli. Here we compared such stimuli with a more naturalistic stimulus. Previous work on the primary visual cortex showed that direct attentional modulation evokes a blood flow (CBF) response with a relatively large oxygen metabolism (CMRO2) response in comparison to an unattended stimulus, which evokes a much smaller metabolic response relative to the flow response. We hypothesized that a similar effect would be associated with a more engaging stimulus, and tested this by measuring the primary human visual cortex response to two contrast levels of a radial flickering checkerboard in comparison to the response to free viewing of brief movie clips. We did not find a significant difference in the blood flow-metabolism coupling (n=%ΔCBF/%ΔCMRO2) between the movie stimulus and the flickering checkerboards employing two different analysis methods: a standard analysis using the Davis model and a new analysis using a heuristic model dependent only on measured quantities. This finding suggests that in the primary visual cortex a naturalistic stimulus (in comparison to a simple repetitive stimulus) is either not sufficient to provoke a change in flow-metabolism coupling by attentional modulation as hypothesized, that the experimental design disrupted the cognitive processes underlying the response to a more natural stimulus, or that the technique used is not sensitive enough to detect a small difference.

  8. Effects of Yunnan Baiyao through inner layer of cerebral dura mater on cerebral perfusion and oxygen metabolism in rabbits with severe traumatic brain injury%硬脑膜夹层导入云南白药对兔重型颅脑创伤后脑灌注和氧代谢的影响

    Institute of Scientific and Technical Information of China (English)

    徐震; 吕晓皑; 尹利明; 竺国充; 张昕; 李徐; 陈祖鹏

    2012-01-01

    Objective: To explore the effects of Yunnan Baiyao through inner layer of cerebral dura mater on cerebral perfusion and oxygen metabolism in rabbits with severe traumatic brain injury. Methods: 40 New Zealand white rabbits were divided into cerebral dura mater Yunnan Baiyao group(A group), intravenous Mannitol group(B group), oral Yunnan Baiyao group (C group) and control group(D group). Record ICP, CPP and MABP. TCD measured cerebral blood flow volume. Monitor blood gas analysis in femora) artery and internal jugular venous bulb, accounting the CEO2 and D-values of glucose and lactic acid between artery and venous bulb. Results: From 12 to 36 hour after therapy: the ICP of A was highter than B, the CPP and CBFV were lower than B (P<0.05). At 48 hour: the ICP of A was highter than B and lower than C and D, the CPP was lower than B and highter than Cand D, while the CBFV of A was highter than C and D(P<0.05). From 60 to 96 hour: the ICP of A was lower than C and D, the CPP of A was highter than C and D, the CBFV of A was highter than B, C and D(P<0.05). From 36 to 96: The Glua-jv and CEO2 of A were highter than B, C and D, while the Lacjv-a was lower than B, C and D(P<0.05). Conclusion: Yunnan Baiyao through cerebral dura mater can reach effective treatment concentration in brain. By increasing the efficiency of oxygen metabolism of brain it can ameliorate brain cell hypoxia and energy metabolism handicap, adjust cerebral microcirculation, thus improves cytotoxic brain edema, decreases cerebral blood flow resistance, reduces ICP and increase the CPP and CBFV.%目的:探讨硬脑膜夹层应用云南白药对兔重型颅脑创伤后颅内压、脑血流量和脑代谢的影响.方法:将40只雄性新西兰大白兔分为硬脑膜夹层云南白药组(A组)、静脉甘露醇组(B组)、口服云南白药组(C组)和空白组(D组),制作重型颅脑创伤模型,行颅内压(ICP)监测,记录平均动脉压(MABP),计算脑灌注压(CPP),经颅多普勒(TCD)测定脑

  9. Recirculation usually precedes malignant edema in middle cerebral artery infarcts

    DEFF Research Database (Denmark)

    Nielsen, T H; Ståhl, N; Schalén, W;

    2012-01-01

    In patients with large middle cerebral artery (MCA) infarcts, maximum brain swelling leading to cerebral herniation and death usually occurs 2-5 days after onset of stroke. The study aimed at exploring the pattern of compounds related to cerebral energy metabolism in infarcted brain tissue....

  10. 早期高压氧治疗对急性颅脑外伤患者失语症的疗效观察%Effects of early hyperbaric oxygen therapy on alogia in acute cerebral injury

    Institute of Scientific and Technical Information of China (English)

    林瑛; 李泉清; 刘代娣; 杨静; 张其清

    2009-01-01

    目的 研究早期高压氧(HBO)治疗对急性颅脑外伤患者失语症的疗效.方法 将2004年1月至2007年8月在我院住院的62例急性颅脑外伤患者分为HBO治疔组和常规治疗组,常规治疗组采用临床常规治疗,HBO治疗组在常规治疗的基础上,实施24~48次HBO治疗,并且在治疗结束后1年内每3个月进行1次随访.在治疗前、后分别采用西方失语成套测试法(western aphasia,WAB)检测并进行CT检查,对他们的语言功能和恢复情况进行评价和比较.结果 HBO治疗组显效率(83.8%)显著高于常规治疗组(54.8%),经x2检验P<0.05;CT检查证实患者病变部位阻塞的血管已经恢复冉通或已获得重建.结论 早期HBO治疗有利于促进或恢复患者的语言功能.%Objective To investigate the effects of early hyperbaric oxygen therapy on aphasia in acute cerebral injury. Methods Sixty-two patients with acute cerebral injury were admitted into the hospital from January 2004 to August 2007. They were randomly divided into the hyperbaric oxygen (HBO) group and the control group. The control group was administered with routine treatment other than HBO, while the HBO group was given 24-48 sessions of HBO treatment in addition to routine treatment. To know how they recovered, clinical follow-ups were made every 3 months, one year after the patients terminated treatment. The linguistic function of the patients was evaluated and compared by using Western Aphasia Battery (WAB) and CT before and after HBO therapy. Results Results showed that the HBO exposure group had obviously better results when it was compared with the control group ( 83. 8% : 54. 8% ). And test showed that P < 0, 05. CT examination demonstrated that the blocked vessels in the affected area were either recovered or repaired. Conclusions Early HBO therapy will help to improve or recover the linguistic function of patients with acute cerebral injury.

  11. Insulin improves in vitro survival of equine preantral follicles enclosed in ovarian tissue and reduces reactive oxygen species production after culture.

    Science.gov (United States)

    Aguiar, F L N; Lunardi, F O; Lima, L F; Rocha, R M P; Bruno, J B; Magalhães-Padilha, D M; Cibin, F W S; Rodrigues, A P R; Gastal, M O; Gastal, E L; Figueiredo, J R

    2016-04-01

    This study investigated the effect of insulin concentration on the in vitro culture of equine preantral follicles enclosed in ovarian tissue. Ovarian tissue samples were immediately fixed (noncultured control) or cultured for 1 or 7 days in α-MEM(+) supplemented with 0 ng/mL, 10 ng/mL, or 10 μg/mL insulin. Ovarian tissues were processed and analyzed by classical histology. Culture medium samples were collected after 1 and 7 days of culture for steroid and reactive oxygen species (ROS) analyses. The percentage of morphologically normal follicles was greater (P culture; likewise, more (P culture in medium supplemented with 10-ng/mL insulin. Furthermore, an increase (P culture was observed only with the 10-ng/mL insulin treatment. ROS production after 1 or 7 days of culture was lower (P culture; however, treatments did not differ in steroid production. In conclusion, the use of a physiological concentration (10 ng/mL) of insulin rather than the previously reported concentration (10 μg/mL) for in vitro culture of equine preantral follicles improved follicular survival and growth and lowered oxidative stress. Results from this study shed light on new perspectives for producing an appropriate medium to improve equine preantral follicle in vitro survival and growth.

  12. Effects of reactive oxygen species on metabolism monitored by longitudinal {sup 1}H single voxel MRS follow-up in patients with mitochondrial disease or cerebral tumors

    Energy Technology Data Exchange (ETDEWEB)

    Constans, J M; Collet, S; Hossu, G; Courtheoux, P [MRI Unit, Caen University Hospital, Caen, Normandy (France); Guillamo, J S; Lechapt-Zalcman, E; Valable, S [CERVOxy Group, CI-NAPS, UMR 6232 CI-NAPS, Cyceron, Caen, Normandy (France); Lacombe, S; Houee Levin, C [Paris-Sud 11 University-CNRS, Orsay (France); Gauduel, Y A [LOA, Ecole Polytechnique - ENSTA ParisTech, Palaiseau (France); Dou, W [Tsinghua University, Beijing (China); Ruan, S [CReSTIC EA 3804, IUT Troyes, Troyes (France); Barre, L [GDMTEP, Group CI-NAPS, UMR 6232 CI-NAPS, Cyceron, Caen (France); Rioult, F [CNRS UMR 6072, GREYC, Caen, Normandy (France); Derlon, J M [Neurosurgery and Neurology, Caen University Hospital, Caen, Normandy (France); Chapon, F [Pathology, Caen University Hospital, Caen, Normandy (France); Fong, V [Caen University (France); Kauffmann, F, E-mail: constans-jm@chu-caen.fr [Mathematics LMNO CNRS UMR 6139, Caen University, Caen, Normandy (France)

    2011-01-01

    Free radicals, or Reactive Oxygen Species (ROS), have an effect on energy and glycolytic metabolism, mitochondrial function, lipid metabolism, necrosis and apoptosis, cell proliferation, and infiltration. These changes could be monitored longitudinally (every 4 months over 6 years) in humans with glial brain tumors (low and high grade) after therapy, using conventional magnetic resonance imaging (MRI) and spectroscopy (MRS) and MR perfusion. Some examples of early clinical data from longitudinal follow-up monitoring in humans of energy and glycolytic metabolism, lipid metabolism, necrosis, proliferation, and infiltration measured by conventional MRI, MRS and perfusion, and positron emission tomography (PET) are shown in glial brain tumors after therapy. Despite the difficulty, the variability and unknown factors, these repeated measurements give us a better insight into the nature of the different processes, tumor progression and therapeutic response.

  13. Vasoespasmo cerebral

    OpenAIRE

    1987-01-01

    Vasoespasmo cerebral ocorre em patologias como enxaqueca, hemorragia subaracnóidea, trauma de crânio, após isquemia e/ou hipoxia. A fisiopatologia do vasoespasmo cerebral nestas patologias não está completamente desvendada. Neste artigo são analisados os fatores neuroquímicos e morfológicos responsáveis pelo controle circulatório cerebral. As alterações circulatórias que seguem a hemorragia subaracnóidea são utilizadas como exemplo. Conclui-se que fatores bioquímicos, fisiológicos e morfológi...

  14. Effect of Indomethacin Infused over 30 Minutes on Cerebral Fractional Tissue Oxygen Extraction in Preterm Newborns with a Patent Ductus Arteriosus

    NARCIS (Netherlands)

    Keating, Paul; Verhagen, Elise; van Hoften, Jacorina; ter Horst, Henk; Bos, Arend F.

    2010-01-01

    Background: A significant patent ductus arteriosus (PDA) is a common finding in the first days of life and, if persistent, is associated with an increased morbidity and mortality in the preterm newborn. Objectives: Our aim was to investigate, using near-infrared spectroscopy, the effect of indometha

  15. Application of extracorporeal membrane oxygenation to cardiopulmonary cerebral resuscitation%体外膜肺氧合在心肺脑复苏中的应用

    Institute of Scientific and Technical Information of China (English)

    蒋崇慧; 黄子通; 谢钢; 李斌飞; 宁晔; 吴美英; 郑伟华; 尹刚; 赵双彪

    2008-01-01

    Objective To investigate the effects and values of extracorporeal membrane oxygenation (EC-MO) used in patients after cardiac arrest. Method During five years period from June 2002 to June 2007,fifteen cases taken for cardiopulmonary resuscitation were treated by using ECMO in the emergency department and ICU. All the measures for disgnosis and treatment were observed to the guidelines for cardiopulmonary resuscitation and emergency cardiovasculat care set by the American Heart Association in 2005, and ECMO was applied in addition. The study was a self-comparison trial. The biomarkers including heart rate (HR), mean arterial pressure (MAP), central venous pressure( CVP) , arterial partial oxygen pressure (PaO2), arterial partial pressure of carbon dioxide ( PCQ2), oxygen saturation (SaO2), hydrogen power (PH), and concentration of lactic acid were taken and assayed before and 10 min, 1 h,6 h, 12 h, and 24 h after treatment. Differences between the results of measurements were analysed by t -test for matched pairs using SPSS version 10.0 software package. Neurological sequelae was also observed and described. Results Ten minutes after ECMO treatment, MAP rose dramatically (P 的标准诊治方案进行救治,同时行体外膜肺氧合(ECMO)治疗.采用治疗前后自身对照的方法,监测ECMO治疗前、ECMO治疗后10 min、1 h、6 h、12 h、24 h,患者的心率、平均动脉压、中心静脉压(eve);并抽取桡动脉血检测动脉血氧分压、二氧化碳分压、血氧饱和度、酸碱度、动脉血乳酸含量等指标;统计数据以((x)±s)表示,采用SPSS 10.0统计软件包进行t检验,以P<0.05为差异具有统计学意义;同时就患者的神经性后遗症进行了观察和描述.结果 平均动脉压在ECMO治疗后10min比ECMO治疗前明显升高(P<0.01),ECMO治疗后1 h比ECMO治疗后10 min有所升高(P<0.05);CVP在ECMO治疗后10 min比ECMO治疗前,ECMO治疗后1 h比ECMO治疗后10 min有所降低(P<0.05);经ECMO治疗后10

  16. Paragonimus westermani possesses aerobic and anaerobic mitochondria in different tissues, adapting to fluctuating oxygen tension in microaerobic habitats.

    Science.gov (United States)

    Takamiya, Shinzaburo; Fukuda, Koich; Nakamura, Takeshi; Aoki, Takashi; Sugiyama, Hiromu

    2010-12-01

    We previously showed that adult Paragonimus westermani, the causative agent of paragonimiasis and whose habitat is the host lung, possesses both aerobic and anaerobic respiratory chains, i.e., cyanide-sensitive succinate oxidase and NADH-fumarate reductase systems, in isolated mitochondria (Takamiya et al., 1994). This finding raises the intriguing question as to whether adult Paragonimus worms possess two different populations of mitochondria, one having an aerobic succinate oxidase system and the other an anaerobic fumarate reductase system, or whether the worms possess a single population of mitochondria possessing both respiratory chains (i.e., mixed-functional mitochondria). Staining of trematode tissues for cytochrome c oxidase activity showed three types of mitochondrial populations: small, strongly stained mitochondria with many cristae, localised in the tegument and tegumental cells; and two larger parenchymal cell mitochondria, one with developed cristae and the other with few cristae. The tegumental and parenchymal mitochondria could be separated by isopycnic density-gradient centrifugation and showed different morphological characteristics and respiratory activities, with low-density tegumental mitochondria having cytochrome c oxidase activity and high-density parenchymal mitochondria having fumarate reductase activity. These results indicate that Paragonimus worms possess three different populations of mitochondria, which are distributed throughout trematode tissues and function facultatively, rather than having mixed-functional mitochondria.

  17. Oxygen deprivation and the cellular response to hypoxia in adipocytes - perspectives on white and brown adipose tissues in obesity.

    Science.gov (United States)

    Trayhurn, Paul; Alomar, Suliman Yousef

    2015-01-01

    Relative hypoxia has been shown to develop in white adipose tissue depots of different types of obese mouse (genetic, dietary), and this leads to substantial changes in white adipocyte function. These changes include increased production of inflammation-related adipokines (such as IL-6, leptin, Angptl4, and VEGF), an increase in glucose utilization and lactate production, and the induction of fibrosis and insulin resistance. Whether hypoxia also occurs in brown adipose tissue depots in obesity has been little considered. However, a recent study has reported low pO2 in brown fat of obese mice, this involving mitochondrial loss and dysfunction. We suggest that obesity-linked hypoxia may lead to similar alterations in brown adipocytes as in white fat cells - particularly changes in adipokine production, increased glucose uptake and lactate release, and insulin resistance. This would be expected to compromise thermogenic activity and the role of brown fat in glucose homeostasis and triglyceride clearance, underpinning the development of the metabolic syndrome. Hypoxia-induced augmentation of lactate production may also stimulate the "browning" of white fat depots through recruitment of UCP1 and the development of brite adipocytes.

  18. Quantitative spatially resolved measurement of tissue chromophore concentrations using photoacoustic spectroscopy: application to the measurement of blood oxygenation and haemoglobin concentration

    Energy Technology Data Exchange (ETDEWEB)

    Laufer, Jan; Delpy, Dave; Elwell, Clare; Beard, Paul [Department of Medical Physics and Bioengineering, University College London, Malet Place Engineering Building, London WC1E 6BT (United Kingdom)

    2007-01-07

    A new approach based on pulsed photoacoustic spectroscopy for non-invasively quantifying tissue chromophore concentrations with high spatial resolution has been developed. The technique is applicable to the quantification of tissue chromophores such as oxyhaemoglobin (HbO{sub 2}) and deoxyhaemoglobin (HHb) for the measurement of physiological parameters such as blood oxygen saturation (SO{sub 2}) and total haemoglobin concentration. It can also be used to quantify the local accumulation of targeted contrast agents used in photoacoustic molecular imaging. The technique employs a model-based inversion scheme to recover the chromophore concentrations from photoacoustic measurements. This comprises a numerical forward model of the detected time-dependent photoacoustic signal that incorporates a multiwavelength diffusion-based finite element light propagation model to describe the light transport and a time-domain acoustic model to describe the generation, propagation and detection of the photoacoustic wave. The forward model is then inverted by iteratively fitting it to measurements of photoacoustic signals acquired at different wavelengths to recover the chromophore concentrations. To validate this approach, photoacoustic signals were generated in a tissue phantom using nanosecond laser pulses between 740 nm and 1040 nm. The tissue phantom comprised a suspension of intralipid, blood and a near-infrared dye in which three tubes were immersed. Blood at physiological haemoglobin concentrations and oxygen saturation levels ranging from 2% to 100% was circulated through the tubes. The signal amplitude from different temporal sections of the detected photoacoustic waveforms was plotted as a function of wavelength and the forward model fitted to these data to recover the concentrations of HbO{sub 2} and HHb, total haemoglobin concentration and SO{sub 2}. The performance was found to compare favourably to that of a laboratory CO-oximeter with measurement resolutions of {+-}3

  19. Near-Infrared Spectroscopy for Objectifying Cerebral Effects of Laser Acupuncture in Term and Preterm Neonates

    Directory of Open Access Journals (Sweden)

    Wolfgang Raith

    2013-01-01

    Full Text Available Laser acupuncture (LA becomes more and more relevant in neonates and infants. With near-infrared spectroscopy (NIRS, a continuous and noninvasive measurement of tissue oxygenation is possible. Aim was to investigate, whether the application of LA was associated with any changes in regional cerebral oxygen saturation (rcSO2 in term and preterm neonates. The study included 20 neonates (12 males, 8 females. The Large Intestine 4 acupuncture point (LI 4, Hegu was stimulated by a microlaser needle (10 mW, 685 nm laser needle EG GmbH, Germany for 5 minutes, bilaterally. All neonates underwent polygraphic recording during undisturbed daytime sleep, including heart rate (HR, peripheral oxygen saturation (SpO2, and measurement of nasal flow. Using NIRS, rcSO2 was measured continuously. Cerebral fractional tissue oxygen extraction (cFTOE was calculated. We did not observe any significant changes in SpO2 and HR values during the whole observation period. However, there was a significant decrease in rcSO2 (P=0.003 within postintervention period, accompanied by a significant increase in cFTOE (P=0.010 in postintervention period.

  20. Dynamic oxygen-enhanced MRI of cerebrospinal fluid.

    Directory of Open Access Journals (Sweden)

    Taha M Mehemed

    Full Text Available Oxygen causes an increase in the longitudinal relaxation rate of tissues through its T1-shortening effect owing to its paramagnetic properties. Due to such effects, MRI has been used to study oxygen-related signal intensity changes in various body parts including cerebrospinal fluid (CSF space. Oxygen enhancement of CSF has been mainly studied using MRI sequences with relatively longer time resolution such as FLAIR, and T1 value calculation. In this study, fifteen healthy volunteers were scanned using fast advanced spin echo MRI sequence with and without inversion recovery pulse in order to dynamically track oxygen enhancement of CSF. We also focused on the differences of oxygen enhancement at sulcal and ventricular CSF. Our results revealed that CSF signal after administration of oxygen shows rapid signal increase in both sulcal CSF and ventricular CSF on both sequences, with statistically significant predominant increase in sulcal CSF compared with ventricular CSF. CSF is traditionally thought to mainly form from the choroid plexus in the ventricles and is absorbed at the arachnoid villi, however, it is also believed that cerebral arterioles contribute to the production and absorption of CSF, and controversy remains in terms of the precise mechanism. Our results demonstrated rapid oxygen enhancement in sulcal CSF, which may suggest inhaled oxygen may diffuse into sulcal CSF space rapidly probably due to the abundance of pial arterioles on the brain sulci.

  1. A prospective, randomized, controlled study of hyperbaric oxygen therapy: effects on healing and oxidative stress of ulcer tissue in patients with a diabetic foot ulcer.

    Science.gov (United States)

    Ma, Le; Li, Pingsong; Shi, Zehong; Hou, Tuanjie; Chen, Xiao; Du, Jin

    2013-03-01

    Although hyperbaric oxygen (HBO) therapy has been reported to help heal chronic foot ulcers in patients with diabetes mellitus (DM), production of HBO-related oxidative stress is a concern. To assess the therapeutic effect and oxidative stress of HBO, a 2-week, prospective, randomized, controlled clinical study was conducted from January 1, 2010 to January1, 2012 among 36 consecutively admitted patients with diabetic foot ulcers (DFU). Average patient age was 60.08 ± 5.97 years and average DM duration was 16.4 ± 11.3 years; 86.1% had type 2 DM, and 47.2% had Wagner grade-III foot ulcers. Patients randomized to the control group (n = 18) received standard care including offloading, wound debridement, and glucose control. HBO treatment group patients (n = 18) received standard care and twice-daily HBO sessions for 90 minutes at 2.5 atmospheres absolute (ATA) 5 days a week for 2 weeks. Transcutaneous oxygen pressure (TcPo2) at the edge of the ulcer and wound size were measured at baseline and after 7 and 14 days of treatment. Ulcer tissues were harvested on days 7 and 14 to determine oxidative stress by measuring malondialdehyde (MDA) and antioxidant enzyme (superoxide dismutase [SOD], catalase [CAT], and glutathione peroxidase [GPx]) levels. Compared to baseline, TcPo2 in the HBO group increased on day 7 (477.8 ± 118.2 mm Hg versus 37.06 ± 5.23 mm Hg, P Ulcer size reduction in the HBO group was greater than that of the control group (42.4% ± 20.0% versus 18.1% ± 6.5%, P ulcer tissue may offset this effect long-term. Until needed additional research has been conducted, prolonged and/or inappropriate HBO treatment should be avoided.

  2. Changes of regional cerebral blood oxygenation in recognizing Chinese characters in children with Chinese dyslexia%汉语阅读障碍儿童汉字识别过程中脑血氧的变化

    Institute of Scientific and Technical Information of China (English)

    宋然然; 吴汉荣

    2006-01-01

    化量明显高于对照组(0.073 0,-0.072 1,F=15.59,P<0.01).结论:汉字认知过程阅读障碍儿童左前额叶皮层虽然激活,但相对正常儿童,激活的程度和激活模式均有差异,提示特定脑区功能异常可能是阅读障碍发生的生物学基础.%BACKGROUND: Dyslexia is the most common in the study of learning disabilities, it can affect various aspects of children, including behaviors,cognition, emotion, social adaptation, etc., and seriously block their obtaining of knowledge and improvement of ability in children.OBJECTIVE: To study the changing law of regional cerebral blood oxygenation in children with Chinese dyslexia in the process of recognizing Chinese characters, and investigate the neurophysiological basis of dyslexia in children.DESIGN: A case-control study.SETTING: Department of Child and Adolescent Health and Maternal Care, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology.PARTICIPANTS: The study was carried out in Huazhong University of Science and Technology from June to September in 2003. Forty-five primary students of 8 to 12 years old, who were grade 3 to 5 in Wuhan city,were enrolled in this study, including 26 dyslexic children (dyslexia group)and 19 normal readers (control group). All the enrolled children were righthanded. Informed consents were obtained from all the participants and their parents (guardians) after explanation of aims and steps of this study.METHODS: The functional near-infrared imager (fNIRI) was applied to detect the changes of cerebral blood oxygenation in left prefrontal lobe of dyslexic children and normal children in the primary processing (viewing passively, reading aloud, producing an action word) and secondary processing of Chinese characters (outputting task, action words association) of Chinese characters.MAIN OUTCOME MEASURES: The changes of cerebral blood oxygenation in the primary processing and secondary processing of Chinese characters were observed in both

  3. Propofol prevents autophagic cell death following oxygen and glucose deprivation in PC12 cells and cerebral ischemia-reperfusion injury in rats.

    Directory of Open Access Journals (Sweden)

    Derong Cui

    Full Text Available BACKGROUND: Propofol exerts protective effects on neuronal cells, in part through the inhibition of programmed cell death. Autophagic cell death is a type of programmed cell death that plays elusive roles in controlling neuronal damage and metabolic homeostasis. We therefore studied whether propofol could attenuate the formation of autophagosomes, and if so, whether the inhibition of autophagic cell death mediates the neuroprotective effects observed with propofol. METHODOLOGY/PRINCIPAL FINDINGS: The cell model was established by depriving the cells of oxygen and glucose (OGD for 6 hours, and the rat model of ischemia was introduced by a transient two-vessel occlusion for 10 minutes. Transmission electron microscopy (TEM revealed that the formation of autophagosomes and autolysosomes in both neuronal PC12 cells and pyramidal rat hippocampal neurons after respective OGD and ischemia/reperfusion (I/R insults. A western blot analysis revealed that the autophagy-related proteins, such as microtubule-associated protein 1 light chain 3 (LC3-II, Beclin-1 and class III PI3K, were also increased accordingly, but cytoprotective Bcl-2 protein was decreased. The negative effects of OGD and I/R, including the formation of autophagosomes and autolysosomes, the increase in LC3-II, Beclin-1 and class III PI3K expression and the decline in Bcl-2 production were all inhibited by propofol and specific inhibitors of autophagy, such as 3-methyladenine (3-MA, LY294002 and Bafilomycin A1 (Baf,. Furthermore, in vitro OGD cultures and in vivo I/R rats showed an increase in cell survival following the administration of propofol, as assessed by an MTT assay or histochemical analyses. CONCLUSIONS/SIGNIFICANCE: Our data suggest that propofol can markedly attenuate autophagic processes via the decreased expression of autophagy-related proteins in vitro and in vivo. This inhibition improves cell survival, which provides a novel explanation for the pleiotropic effects of

  4. Deletion of TRPC6 Attenuates NMDA Receptor-Mediated Ca2+ Entry and Ca2+-Induced Neurotoxicity Following Cerebral Ischemia and Oxygen-Glucose Deprivation

    Science.gov (United States)

    Chen, Jin; Li, Zhaozhong; Hatcher, Jeffery T.; Chen, Qing-Hui; Chen, Li; Wurster, Robert D.; Chan, Sic L.; Cheng, Zixi

    2017-01-01

    Transient receptor potential canonical 6 (TRPC6) channels are permeable to Na+ and Ca2+ and are widely expressed in the brain. In this study, the role of TRPC6 was investigated following ischemia/reperfusion (I/R) and oxygen-glucose deprivation (OGD). We found that TRPC6 expression was increased in wild-type (WT) mice cortical neurons following I/R and in primary neurons with OGD, and that deletion of TRPC6 reduced the I/R-induced brain infarct in mice and the OGD- /neurotoxin-induced neuronal death. Using live-cell imaging to examine intracellular Ca2+ levels ([Ca2+]i), we found that OGD induced a significant higher increase in glutamate-evoked Ca2+ influx compared to untreated control and such an increase was reduced by TRPC6 deletion. Enhancement of TRPC6 expression using AdCMV-TRPC6-GFP infection in WT neurons increased [Ca2+]i in response to glutamate application compared to AdCMV-GFP control. Inhibition of N-methyl-d-aspartic acid receptor (NMDAR) with MK801 decreased TRPC6-dependent increase of [Ca2+]i in TRPC6 infected cells, indicating that such a Ca2+ influx was NMDAR dependent. Furthermore, TRPC6-dependent Ca2+ influx was blunted by blockade of Na+ entry in TRPC6 infected cells. Finally, OGD-enhanced Ca2+ influx was reduced, but not completely blocked, in the presence of voltage-dependent Na+ channel blocker tetrodotoxin (TTX) and dl-α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) blocker CNQX. Altogether, we concluded that I/R-induced brain damage was, in part, due to upregulation of TRPC6 in cortical neurons. We postulate that overexpression of TRPC6 following I/R may induce neuronal death partially through TRPC6-dependent Na+ entry which activated NMDAR, thus leading to a damaging Ca2+ overload. These findings may provide a potential target for future intervention in stroke-induced brain damage.

  5. Cerebral hemodynamics: concepts of clinical importance

    Directory of Open Access Journals (Sweden)

    Edson Bor-Seng-Shu

    2012-05-01

    Full Text Available Cerebral hemodynamics and metabolism are frequently impaired in a wide range of neurological diseases, including traumatic brain injury and stroke, with several pathophysiological mechanisms of injury. The resultant uncoupling of cerebral blood flow and metabolism can trigger secondary brain lesions, particularly in early phases, consequently worsening the patient's outcome. Cerebral blood flow regulation is influenced by blood gas content, blood viscosity, body temperature, cardiac output, altitude, cerebrovascular autoregulation, and neurovascular coupling, mediated by chemical agents such as nitric oxide (NO, carbon monoxide (CO, eicosanoid products, oxygen-derived free radicals, endothelins, K+, H+, and adenosine. A better understanding of these factors is valuable for the management of neurocritical care patients. The assessment of both cerebral hemodynamics and metabolism in the acute phase of neurocritical care conditions may contribute to a more effective planning of therapeutic strategies for reducing secondary brain lesions. In this review, the authors have discussed concepts of cerebral hemodynamics, considering aspects of clinical importance.

  6. 七氟醚-瑞芬太尼麻醉对缺血型烟雾病脑血管重建术患者脑氧供需平衡的影响%Effects of sevoflurane-remifentanil anesthesia on the balance between cerebral oxygen supply and demand during cerebral revascularization for ischemic moyamoya disease

    Institute of Scientific and Technical Information of China (English)

    梁发; 崔伟华; 何颖; 焦希平; 王嵘; 张东; 韩如泉

    2013-01-01

    目的 评价七氟醚-瑞芬太尼麻醉对缺血型烟雾病脑血管重建术患者脑氧供需平衡的影响.方法 择期行颞浅动脉-大脑中动脉分支吻合术的缺血型烟雾病患者40例,性别不限,年龄19~ 59岁,BMI 19~ 25 kg/m2,ASA分级Ⅰ或Ⅱ级,Suzuki分期≥3.采用随机数字表法,将患者随机分为2组(n=20):异丙酚-瑞芬太尼组(PR组)和七氟醚-瑞芬太尼组(SR组).麻醉诱导:靶控输注异丙酚,血浆靶浓度5 μg/ml,静脉注射芬太尼3 μg/kg和罗库溴铵0.6 mg/kg.气管插管后行机械通气,麻醉维持:SR组吸入七氟醚(呼气末浓度1.0% ~ 1.7%),PR组TCI异丙酚,血浆靶浓度3~4 μg/ml,2组均TCI瑞芬太尼,血浆靶浓度3.5 ng/ml,维持BIS值40 ~ 60,间断静脉注射罗库溴铵0.3 mg/kg.分别于麻醉诱导前(T0)、血管阻断前10 min (T1)、血管阻断后10 min (T2)、血管吻合-开放后10 min (T3)时记录局部脑氧饱和度(rSO2).结果 与T0时比较,PR组T3时术侧rSO2升高,SR组T1-3时术侧和非术侧rSO2升高(P<0.05或0.01);与PR组比较,SR组T1时术侧rSO2升高(P<0.05),非术侧rSO2差异无统计学意义(P>0.05).结论 对于缺血型烟雾病脑血管重建术患者,七氟醚复合瑞芬太尼麻醉可维持良好的脑氧供需平衡状态,且与异丙酚复合瑞芬太尼麻醉的效果相似.%Objective To evaluate the effects of sevoflurane-remifentanil anesthesia on the balance between cerebral oxygen supply and demand during cerebral revascularization for ischemic moyamoya disease by monitoring regional cerebral O2 saturation (rSO2) with near infrared spectroscopy.Methods Forty patients of both sexes aged 19-59 yr with a body mass index of 19-25 kg/m2 undergoing superficial temporal artery-middle cerebral artery anastomosis were randomly allocated into 2 groups (n =20 each):propofol-remifentanil group (group PR) and sevoflurane-remifentanil group (group SR).Radial artery was cannulated for direct BP monitoring and blood sampling

  7. Effects of blockade of cerebral lymphatic dra inage on oxide free radical in brain tissue after middle cerebral artery occlu sion in rats%脑淋巴引流阻滞对大脑中动脉阻塞鼠缺血性脑组织氧自由基的影响

    Institute of Scientific and Technical Information of China (English)

    夏作理; 孙保亮; 闫振文; 杨明峰; 陈玉社

    2001-01-01

    Objective To investigate the effects of blo c kade of cerebrallymphatic drainage on oxide free radicals in ischemic brain tis sue.Methods Seventy six Wistar rats were divided randomly int o two groups,the middle cerebral artery occlusion(MCAO) group and MCAO plus cere bral lymphatic blockade(MCAO+CLB)group.Activity of SOD and content of MDA in the ischemic brain tissu es were detected at 24 hours,48 hours and 72 hours respectively after operation.Results In MCAO group,SOD activity in the ischemic brain tissue was significantly decreased while MDA content was increased markedly.In M CAO+CLB group,alterations of above parameters were more obvious.Conclusions Obstruction of cerebral lymphatic drainage may deteriorate ischemic brain damage by increasing oxide free radicals.%目的 探讨脑淋巴引流阻滞对脑缺血后脑组织氧自由基的影响。方法 将76只Wistar大鼠随机分为大脑中动脉阻塞(MCAO)组和MCAO加脑淋巴引流阻断(MCAO+CLB)组,在术后24h、48h和72h分别检测SOD活性和MDA含量的变化。结果 在手术后各时间点,MCAO大鼠缺血区脑组织SOD活力显著降低而MDA含量明显增多,在MCAO+CLB大鼠上述指标的变化更加严重。结论 脑淋巴引流障碍能通过增加缺血区脑组织的氧自由基含而加重MCAO后缺血性脑损伤。

  8. Oxygen sensing and signaling.

    Science.gov (United States)

    van Dongen, Joost T; Licausi, Francesco

    2015-01-01

    Oxygen is an indispensable substrate for many biochemical reactions in plants, including energy metabolism (respiration). Despite its importance, plants lack an active transport mechanism to distribute oxygen to all cells. Therefore, steep oxygen gradients occur within most plant tissues, which can be exacerbated by environmental perturbations that further reduce oxygen availability. Plants possess various responses to cope with spatial and temporal variations in oxygen availability, many of which involve metabolic adaptations to deal with energy crises induced by low oxygen. Responses are induced gradually when oxygen concentrations decrease and are rapidly reversed upon reoxygenation. A direct effect of the oxygen level can be observed in the stability, and thus activity, of various transcription factors that control the expression of hypoxia-induced genes. Additional signaling pathways are activated by the impact of oxygen deficiency on mitochondrial and chloroplast functioning. Here, we describe the molecular components of the oxygen-sensing pathway.

  9. Aerobic training in children with cerebral palsy.

    Science.gov (United States)

    Nsenga, A L; Shephard, R J; Ahmaidi, S; Ahmadi, S

    2013-06-01

    Rehabilitation is a major goal for children with cerebral palsy, although the potential to enhance cardio-respiratory fitness in such individuals remains unclear. This study thus compared current cardio-respiratory status between children with cerebral palsy and able-bodied children, and examined the ability to enhance the cardio-respiratory fitness of children with cerebral palsy by cycle ergometer training. 10 children with cerebral palsy (Gross Motor Function Classification System levels I and II) participated in thrice-weekly 30 min cycle ergometer training sessions for 8 weeks (mean age: 14.2±1.9 yrs). 10 additional subjects with cerebral palsy (mean age: 14.2±1.8 yrs) and 10 able-bodied subjects (mean age: 14.1±2.1 yrs) served as controls, undertaking no training. All subjects undertook a progressive cycle ergometer test of cardio-respiratory fitness at the beginning and end of the 8-week period. Cardio-respiratory parameters [oxygen intake V˙O2), ventilation V ˙ E) and heart rate (HR)] during testing were measured by Cosmed K4 b gas analyzer. The children with cerebral palsy who engaged in aerobic training improved their peak oxygen consumption, heart rate and ventilation significantly (pchildren with cerebral palsy can benefit significantly from cardio-respiratory training, and such training should be included in rehabilitation programs.

  10. Cerebral blood flow in the neonate.

    Science.gov (United States)

    Vutskits, Laszlo

    2014-01-01

    Ensuring adequate oxygenation of the developing brain is the cornerstone of neonatal critical care. Despite decades of clinical research dedicated to this issue of paramount importance, our knowledge and understanding regarding the physiology and pathophysiology of neonatal cerebral blood flow are still rudimentary. This review primarily focuses on currently available human clinical and experimental data on cerebral blood flow and autoregulation in the preterm and term infant. Limitations of systemic blood pressure values as surrogates for monitoring adequate cerebral oxygen delivery are discussed. Particular emphasis is placed on the high interindividual variability in cerebral blood flow values, vasoreactivity, and autoregulatory thresholds making the applications of normative values highly questionable. Technical and ethical difficulties to conduct such trials leave us with a near complete lack of knowledge on how pharmacological and surgical interventions impact on cerebral autoregulation. The ensemble of these works argues for the necessity of highly individualized care by taking advantage of continuous bedside monitoring of cerebral circulation. They also point to the urgent need for further studies addressing the exciting but difficult issue of cerebral blood flow autoregulation in the neonate.

  11. Speech therapy changes blood circulation and oxygenation in the brain and muscle: a near-infrared spectrophotometry study.

    Science.gov (United States)

    Wolf, Martin; von Bonin, Dietrich; Wolf, Ursula

    2011-01-01

    Recently it has been shown that artistic speech therapy (AST) has effects on heart rate variability. The aim of this pilot study was to investigate whether AST also affects hemodynamics and tissue oxygenation in the brain and skeletal muscle measured by near infrared spectrophotometry(NIRS). The results show that ATS has effects on important physiological parameters, i.e., it leads to a decrease in cerebral blood flow during recitation and to brain activation thereafter.

  12. Cerebral oximetry in cardiac anesthesia

    Science.gov (United States)

    Vretzakis, George; Georgopoulou, Stauroula; Stamoulis, Konstantinos; Stamatiou, Georgia; Tsakiridis, Kosmas; Katsikogianis, Nikolaos; Kougioumtzi, Ioanna; Machairiotis, Nikolaos; Tsiouda, Theodora; Mpakas, Andreas; Beleveslis, Thomas; Koletas, Alexander; Siminelakis, Stavros N.; Zarogoulidis, Konstantinos

    2014-01-01

    Cerebral oximetry based on near-infrared spectroscopy (NIRS) is increasingly used during the perioperative period of cardiovascular operations. It is a noninvasive technology that can monitor the regional oxygen saturation of the frontal cortex. Current literature indicates that it can stratify patients preoperatively according their risk. Intraoperatively, it provides continuous information about brain oxygenation and allows the use of brain as sentinel organ indexing overall organ perfusion and injury. This review focuses on the clinical validity and applicability of this monitor for cardiac surgical patients. PMID:24672700

  13. Cerebral blood flow and metabolism during isoflurane-induced hypotension in patients subjected to surgery for cerebral aneurysms

    DEFF Research Database (Denmark)

    Madsen, J B; Cold, G E; Hansen, E S;

    1987-01-01

    Cerebral blood flow and cerebral metabolic rate for oxygen were measured during isoflurane-induced hypotension in 10 patients subjected to craniotomy for clipping of a cerebral aneurysm. Flow and metabolism were measured 5-13 days after the subarachnoid haemorrhage by a modification of the classi......Cerebral blood flow and cerebral metabolic rate for oxygen were measured during isoflurane-induced hypotension in 10 patients subjected to craniotomy for clipping of a cerebral aneurysm. Flow and metabolism were measured 5-13 days after the subarachnoid haemorrhage by a modification......). Controlled hypotension to an average MAP of 50-55 mm Hg was induced by increasing the dose of isoflurane, and maintained at an inspired concentration of 2.2 +/- 0.2%. This resulted in a significant decrease in CMRO2 (to 1.73 +/- 0.16 ml/100 g min-1), while CBF was unchanged. After the clipping...

  14. Persistent increase in oxygen consumption and impaired neurovascular coupling after spreading depression in rat neocortex

    DEFF Research Database (Denmark)

    Hansen, Henning Piilgaard; Lauritzen, Martin

    2009-01-01

    Cortical spreading depression (CSD) is associated with a dramatic failure of brain ion homeostasis and increased energy metabolism. There is strong clinical and experimental evidence to suggest that CSD is the mechanism of migraine, and involved in progressive neuronal injury in stroke and head...... trauma. Here we tested the hypothesis that single episodes of CSD induced acute hypoxia, and prolonged impairment of neurovascular and neurometabolic coupling. Cortical spreading depression was induced in rat frontal cortex, whereas cortical electrical activity and local field potentials (LFPs) were...... recorded by glass microelectrodes, cerebral blood flow (CBF) by laser-Doppler flowmetry, and tissue oxygen tension (tpO(2)) with polarographic microelectrodes. Cortical spreading depression increased cerebral metabolic rate of oxygen (CMRO(2)) by 71%+/-6.7% and CBF by 238%+/-48.1% for 1 to 2 mins...

  15. Early oxygen-utilization and brain activity in preterm infants.

    Directory of Open Access Journals (Sweden)

    Maria Luisa Tataranno

    Full Text Available The combined monitoring of oxygen supply and delivery using Near-InfraRed spectroscopy (NIRS and cerebral activity using amplitude-integrated EEG (aEEG could yield new insights into brain metabolism and detect potentially vulnerable conditions soon after birth. The relationship between NIRS and quantitative aEEG/EEG parameters has not yet been investigated. Our aim was to study the association between oxygen utilization during the first 6 h after birth and simultaneously continuously monitored brain activity measured by aEEG/EEG. Forty-four hemodynamically stable babies with a GA < 28 weeks, with good quality NIRS and aEEG/EEG data available and who did not receive morphine were included in the study. aEEG and NIRS monitoring started at NICU admission. The relation between regional cerebral oxygen saturation (rScO2 and cerebral fractional tissue oxygen extraction (cFTOE, and quantitative measurements of brain activity such as number of spontaneous activity transients (SAT per minute (SAT rate, the interval in seconds (i.e. time between SATs (ISI and the minimum amplitude of the EEG in μV (min aEEG were evaluated. rScO2 was negatively associated with SAT rate (β=-3.45 [CI=-5.76- -1.15], p=0.004 and positively associated with ISI (β=1.45 [CI=0.44-2.45], p=0.006. cFTOE was positively associated with SAT rate (β=0.034 [CI=0.009-0.059], p=0.008 and negatively associated with ISI (β=-0.015 [CI=-0.026- -0.004], p=0.007. Oxygen delivery and utilization, as indicated by rScO2 and cFTOE, are directly related to functional brain activity, expressed by SAT rate and ISI during the first hours after birth, showing an increase in oxygen extraction in preterm infants with increased early electro-cerebral activity. NIRS monitored oxygenation may be a useful biomarker of brain vulnerability in high-risk infants.

  16. Light scattering change precedes loss of cerebral adenosine triphosphate in a rat global ischemic brain model.

    Science.gov (United States)

    Kawauchi, Satoko; Sato, Shunichi; Ooigawa, Hidetoshi; Nawashiro, Hiroshi; Ishihara, Miya; Kikuchi, Makoto

    2009-08-14

    Measurement of intrinsic optical signals (IOSs) is an attractive technique for monitoring tissue viability in brains since it enables noninvasive, real-time monitoring of morphological characteristics as well as physiological and biochemical characteristics of tissue. We previously showed that light scattering signals reflecting cellular morphological characteristics were closely related to the IOSs associated with the redox states of cytochrome c oxidase in the mitochondrial respiratory chain. In the present study, we examined the relationship between light scattering and energy metabolism. Light scattering signals were transcranially measured in rat brains after oxygen and glucose deprivation, and the results were compared with concentrations of cerebral adenosine triphosphate (ATP) measured by luciferin-luciferase bioluminescence assay. Electrophysiological signal was also recorded simultaneously. After starting saline infusion, EEG activity ceased at 108+/-17s, even after which both the light scattering signal and ATP concentration remained at initial levels. However, light scattering started to change in three phases at 236+/-15s and then cerebral ATP concentration started to decrease at about 260s. ATP concentration significantly decreased during the triphasic scattering change, indicating that the start of scattering change preceded the loss of cerebral ATP. The mean time difference between the start of triphasic scattering change and the onset of ATP loss was about 24s in the present model. DC potential measurement showed that the triphasic scattering change was associated with anoxic depolarization. These findings suggest that light scattering signal can be used as an indicator of loss of tissue viability in brains.

  17. Heart tissue of harlequin (hq)/Big Blue mice has elevated reactive oxygen species without significant impact on the frequency and nature of point mutations in nuclear DNA

    Energy Technology Data Exchange (ETDEWEB)

    Crabbe, Rory A. [Department of Biology, University of Western Ontario, London, Ontario, N6A 5B7 (Canada); Hill, Kathleen A., E-mail: khill22@uwo.ca [Department of Biology, University of Western Ontario, London, Ontario, N6A 5B7 (Canada)

    2010-09-10

    Age is a major risk factor for heart disease, and cardiac aging is characterized by elevated mitochondrial reactive oxygen species (ROS) with compromised mitochondrial and nuclear DNA integrity. To assess links between increased ROS levels and mutations, we examined in situ levels of ROS and cII mutation frequency, pattern and spectrum in the heart of harlequin (hq)/Big Blue mice. The hq mouse is a model of premature aging with mitochondrial dysfunction and increased risk of oxidative stress-induced heart disease with the means for in vivo mutation detection. The hq mutation produces a significant downregulation in the X-linked apoptosis-inducing factor gene (Aif) impairing both the antioxidant and oxidative phosphorylation functions of AIF. Brain and skin of hq disease mice have elevated frequencies of point mutations in nuclear DNA and histopathology characterized by cell loss. Reports of associated elevations in ROS in brain and skin have mixed results. Herein, heart in situ ROS levels were elevated in hq disease compared to AIF-proficient mice (p < 0.0001) yet, mutation frequency and pattern were similar in hq disease, hq carrier and AIF-proficient mice. Heart cII mutations were also assessed 15 days following an acute exposure to an exogenous ROS inducer (10 mg paraquat/kg). Acute paraquat exposure with a short mutant manifestation period was insufficient to elevate mutation frequency or alter mutation pattern in the post-mitotic heart tissue of AIF-proficient mice. Paraquat induction of ROS requires mitochondrial complex I and thus is likely compromised in hq mice. Results of this preliminary survey and the context of recent literature suggest that determining causal links between AIF deficiency and the premature aging phenotypes of specific tissues is better addressed with assay of mitochondrial ROS and large-scale changes in mitochondrial DNA in specific cell types.

  18. Fulminant cerebral infarction of anterior and posterior cerebral circulation after ascending type of facial necrotizing fasciitis.

    Science.gov (United States)

    Lee, Jun Ho; Choi, Hui-Chul; Kim, Chulho; Sohn, Jong Hee; Kim, Heung Cheol

    2014-01-01

    Necrotizing fasciitis is a soft tissue infection that is characterized by extensive necrosis of the subcutaneous fat, neurovascular structures, and fascia. Cerebral infarction after facial necrotizing fasciitis has been rarely reported. A 61-year-old woman with diabetes was admitted with painful swelling of her right cheek. One day later, she was stuporous and quadriplegic. A computed tomographic scan of her face revealed right facial infection in the periorbital soft tissue, parotid, buccal muscle, and maxillary sinusitis. A computed tomographic scan of the brain revealed cerebral infarction in the right hemisphere, left frontal area, and both cerebellum. Four days later, she died from cerebral edema and septic shock. Involvement of the cerebral vasculature, such as the carotid or vertebral artery by necrotizing fasciitis, can cause cerebral infarction. Facial necrotizing fasciitis should be treated early with surgical treatment and the appropriate antibiotic therapy.

  19. The effect of herbs on cerebral energy metabolism in cerebral ischemia-reperfusion mice

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@Vascular dementia is one of the most familiar types of senile dementia. Over the past few years, the research on the damage of cerebral tissues after ischemia has become a focus. The factors and mechanism of cerebral tissue damage after ischemia are very complex. The handicap of energy metabolism is regarded as the beginning factor which leads to the damage of neurons, but its dynamic changes in ischemic area and its role during the process of neuronal damage are not very clear. There are few civil reports on using 31 P nuclear magnetic resonance instrument to explore the changes of cerebral energy metabolism in intravital animals. After exploring the influence of herbs on cerebral energy metabolism in ischemia-reperfusion mice, we came to the conclusion that herbs can improve the cerebral energy metabolism in ischemia-reperfusion mice.

  20. 不同麻醉方法对重症颅脑损伤患者脑氧代谢的影响%Effect of different anesthesia methods on cerebral oxygen metabolism in patients with severe traumatic brain injury

    Institute of Scientific and Technical Information of China (English)

    邹斌

    2013-01-01

    Objective To investigate the effects of different anesthesia methods on cerebral oxygen metabolism in patients with severe traumatic brain injury.Methods Forty-five patients with severe traumatic brain injury from March 2011 to March 2013 were divided into propofol intravenous anesthesia group(group A),sevoflurane inhalation anesthesia group(group B) and intravenous inhalational anesthesia group (group C) by random digits table method with 15 cases each.The mean artery pressure (MAP),heart rate (HR) before anesthesia,immediately after tracheal intubation,2 minutes after intubation,10 min and 30 min after operation set and operation end were observed.The oxygen content of jugular venous (SjvO2),jugular bulb venous oxygen content (Da-jvO2) and cerebral metabolic rate for oxygen (CERO2) before anesthesia induction,immediately finish anesthesia induction,30 min and 1 h after operation set and operatin end were calculated.Results The SjvO2 values in three groups were at 30 min,1 h after operation set and operation end was higher than that before anesthesia induction (group A:0.662 ±0.077,0.689 ±0.067,0.685 ±0.066 vs.0.623 ±0.083; group B:0.661 ±0.074,0.681 ±0.072,0.661 ±0.069 vs.0.598 ±0.092; group C:0.715 ± 0.072,0.743 ± 0.070,0.713 ± 0.075 vs.0.631 ± 0.078),and there was significant difference (P < 0.05).The Da-jvO2 values,CERO2 at 30 min,1 h after operation set and operation end was lower than that before anesthesia induction in three groups [group A:Da-jvO2:(41.2 ± 6.3),(41.6 ± 8.1),(44.2 ± 6.3) ml/L vs.(49.2 ± 9.2) ml/L,CERO2:(33.0 ± 1.9)%,(32.7 ± 2.0)%,(32.3 ± 1.9)% vs.(36.0 ±2.3)%; group B:Da-jvO2:(41.8 ± 5.6),(40.2 ± 6.9),(41.8 ± 5.6) ml/L vs.(51.3 ± 8.6) ml/L,CERO2:(33.2 ±2.1)%,(33.0 ±2.6)%,(32.8 ±2.1)% vs.(34.7 ±3.1)% ; group C:Da-jvO2:(39.5 ±6.8),(38.7 ±7.0),(40.2 ±6.8) ml/L vs.(48.8 ±9.7) ml/L,CERO2:(31.8 ±2.9)%,(31.5 ±3.1)%,(32.9 ±2.3)% vs.(35.1 ± 2.9)%],and there was significant difference (P

  1. Cerebral hemodynamics in patients with obstructive sleep apnea syndrome monitored with near-infrared spectroscopy (NIRS) during positive airways pressure (CPAP) therapy: a pilot study

    Science.gov (United States)

    Zhang, Zhongxing; Schneider, Maja; Laures, Marco; Fritschi, Ursula; Lehner, Isabella; Qi, Ming; Khatami, Ramin

    2014-03-01

    In obstructive sleep apnea syndrome (OSA) the periodic reduction or cessation of breathing due to narrowing or occlusion of the upper airway during sleep leads to daytime symptoms and increased cardiovascular risk, including stroke. The higher risk of stroke is related to the impairment in cerebral vascular autoregulation. Continuous positive airways pressure (CPAP) therapy at night is the most effective treatment for OSA. However, there is no suitable bedside monitoring method evaluating the treatment efficacy of CPAP therapy, especially to monitor the recovery of cerebral hemodynamics. NIRS is ideally suited for non-invasive monitoring the cerebral hemodynamics during sleep. In this study, we will for first time assess dynamic changes of cerebral hemodynamics during nocturnal CPAP therapy in 3 patients with OSA using NIRS. We found periodic oscillations in HbO2, HHb, tissue oxygenation index (TOI) and blood volume associated with periodic apnea events without CPAP in all OSA patients. These oscillations were gradually attenuated and finally eliminated with the stepwise increments of CPAP pressures. The oscillations were totally eliminated in blood volume earlier than in other hemodynamic parameters. These results suggested that 1) the cerebral hemodynamic oscillations induced by OSA events can effectively be attenuated by CPAP therapy, and 2) blood flow and blood volume recovered first during CPAP therapy, followed by the recovery of oxygen consumption. Our study suggested that NIRS is a useful tool to evaluate the efficacy of CPAP therapy in patients with OSA bedside and in real time.

  2. Effects of fluid restriction in combination with small dose of norepinephrine on cerebral oxygen metabolism in elderly patients undergoing gastrointestinal surgery%限制性输液复合小剂量去甲肾上腺素对胃肠道手术老年患者脑氧代谢的影响

    Institute of Scientific and Technical Information of China (English)

    邱晓东; 居斌华; 叶卉; 陆新健; 景亮; 汤文浩

    2015-01-01

    Objective To evaluate the effects of fluid restriction in combination with small dose of norepinephrine on cerebral oxygen metabolism in elderly patients undergoing gastrointestinal surgery.Methods Forty elderly patients of both sexes,aged 65-80 yr,with body mass index of 18-24 kg/m2,of ASA physical status Ⅰ or Ⅱ (NYHA Ⅰ or Ⅱ),with left ventricular ejection fraction≥50%,undergoing elective gastrointestinal surgery,were randomly divided into 2 groups (n =20 each) using a random number table:routine fluid administration group (group S) and restricted fluid administration + small dose of norepinephrine group (group RN).In group S,lactated Ringer's solution was given routinely,ephedrine 5 mg (per time) was injected intravenously,and MAP was maintained ≥ 65 mmHg during operation.In group RN,lactated Ringer's solution was infused intravenously at 5 ml · kg-1 · h-1 starting from 30 min before anesthesia,norepinephrine was infused intravenously at 0.01-0.03 μg · kg-1 · min-1 after induction of anesthesia,and MAP was maintained ≥ 65 mmHg.Intraoperative blood loss was replaced with the equal volume of 6% hydroxyethyl starch 130/0.4 sodium chloride injection in both groups.At 5 min before skin incision,1 and 2 h after skin incision and postanesthesia care unit discharge time,arterial and jugular bulb venous blood samples were obtained for blood gas analysis,and arterial oxygen content,jugular bulb venous oxygen content,arteriovenous oxygen content difference,cerebral oxygen extraction rate,and the ratio of cerebral blood flow to cerebral oxygen metabolic rate were calculated.Results There were no significant differences between the two groups in arterial oxygen content,jugular bulb venous oxygen content,arteriovenous oxygen content difference,cerebral oxygen extraction rate,and the ratio of cerebral blood flow to cerebral oxygen metabolic rate.Conclusion Fluid restriction combined with small dose of norepinephrine produces no effects on cerebral oxygen

  3. Magnetic resonance imaging-based cerebral tissue classification reveals distinct spatiotemporal patterns of changes after stroke in non-human primates

    NARCIS (Netherlands)

    Bouts, Mark. J. R. J.; Westmoreland, Susan. V.; de Crespigny, Alex J.; Liu, Yutong; Vangel, Mark; Dijkhuizen, Rick M.; Wu, Ona; D'Arceuil, Helen E.

    2015-01-01

    Background: Spatial and temporal changes in brain tissue after acute ischemic stroke are still poorly understood. Aims of this study were three-fold: (1) to determine unique temporal magnetic resonance imaging (MRI) patterns at the acute, subacute and chronic stages after stroke in macaques by combi

  4. Brown adipose tissue mitochondria oxidizing fatty acids generate high levels of reactive oxygen species irrespective of the uncoupling protein-1 activity state.

    Science.gov (United States)

    Schönfeld, Peter; Wojtczak, Lech

    2012-03-01

    Mitochondria from brown adipose tissue (BATM) have a high enzymatic capacity for fatty acid oxidation and therefore are an ideal model to examine the sites of reactive oxygen species (ROS) generation during fatty acid oxidation. ROS generation by BATM (isolated from 3-week-old rats) was measured during acylcarnitine oxidation as release of H(2)O(2) into the medium and as inactivation of the matrix enzyme aconitase. The following results were obtained: (1) BATM release large amounts of H(2)O(2) in the coupled as well as in the uncoupled states, several times more than skeletal muscle mitochondria. (2) H(2)O(2) release is especially large with acylcarnitines of medium-chain fatty acids (e.g. octanoylcarnitine). (3) Reverse electron transport does not contribute in a significant extent to the overall ROS generation. (4) Despite the large release of H(2)O(2), the ROS-sensitive matrix enzyme aconitase is not inactivated during acylcarnitine oxidation. (5) In contrast to acylcarnitines, oxidation of α-glycerophosphate by BATM is characterized by large H(2)O(2) release and a pronounced aconitase inactivation. We hypothesize that acylcarnitine-supported ROS generation in BATM may be mainly associated with acyl-CoA dehydrogenase and electron transferring flavoprotein-ubiquinone reductase rather than with complexes of the respiratory chain.

  5. Critical Evaluation of the Changes in Glutamine Synthetase Activity in Models of Cerebral Stroke.

    Science.gov (United States)

    Jeitner, Thomas M; Battaile, Kevin; Cooper, Arthur J L

    2015-12-01

    The following article addresses some seemingly paradoxical observations concerning cerebral glutamine synthetase in ischemia-reperfusion injury. In the brain, this enzyme is predominantly found in astrocytes and catalyzes part of the glutamine-glutamate cycle. Glutamine synthetase is also thought to be especially sensitive to inactivation by the oxygen- and nitrogen-centered radicals generated during strokes. Despite this apparent sensitivity, glutamine synthetase specific activity is elevated in the affected tissues during reperfusion. Given the central role of the glutamine-glutamate cycle in the brain, we sought to resolve these conflicting observations with the view of providing an alternative perspective for therapeutic intervention in stroke.

  6. Perioperative use of cerebral and renal near-infrared spectroscopy in neonates

    DEFF Research Database (Denmark)

    Koch, Henrik W; Hansen, Tom G

    2016-01-01

    BACKGROUND: Neonates undergoing surgery and intensive care still carry a significant morbidity and mortality often related to hypoxic/ischemic events; some of which may go undetected by conventional monitoring. Near-infrared spectroscopy (NIRS) is a noninvasive, continuous method of measuring...... specific regional cerebral and renal monitoring. Despite some practical and economical limitations, NIRS may be considered a useful supplement to perinatal perioperative intensive care....... regional tissue oxygen saturation, and may be used to supplement conventional monitoring to improve neonatal perioperative care. However, high costs and lack of evidence regarding improved outcomes have minimized wider perinatal use of NIRS. The aim of this study was to investigate the applicability...

  7. Cerebral hemodynamic changes of mild traumatic brain injury at the acute stage.

    Directory of Open Access Journals (Sweden)

    Hardik Doshi

    Full Text Available Mild traumatic brain injury (mTBI is a significant public health care burden in the United States. However, we lack a detailed understanding of the pathophysiology following mTBI and its relation to symptoms and recovery. With advanced magnetic resonance imaging (MRI, we can investigate brain perfusion and oxygenation in regions known to be implicated in symptoms, including cortical gray matter and subcortical structures. In this study, we assessed 14 mTBI patients and 18 controls with susceptibility weighted imaging and mapping (SWIM for blood oxygenation quantification. In addition to SWIM, 7 patients and 12 controls had cerebral perfusion measured with arterial spin labeling (ASL. We found increases in regional cerebral blood flow (CBF in the left striatum, and in frontal and occipital lobes in patients as compared to controls (p = 0.01, 0.03, 0.03 respectively. We also found decreases in venous susceptibility, indicating increases in venous oxygenation, in the left thalamostriate vein and right basal vein of Rosenthal (p = 0.04 in both. mTBI patients had significantly lower delayed recall scores on the standardized assessment of concussion, but neither susceptibility nor CBF measures were found to correlate with symptoms as assessed by neuropsychological testing. The increased CBF combined with increased venous oxygenation suggests an increase in cerebral blood flow that exceeds the oxygen demand of the tissue, in contrast to the regional hypoxia seen in more severe TBI. This may represent a neuroprotective response following mTBI, which warrants further investigation.

  8. Cerebral near infrared spectroscopy oximetry in extremely preterm infants

    DEFF Research Database (Denmark)

    Hyttel-Sørensen, Simon; Pellicer, Adelina; Alderliesten, Thomas

    2015-01-01

    in eight European countries. PARTICIPANTS: 166 extremely preterm infants born before 28 weeks of gestation: 86 were randomised to cerebral NIRS monitoring and 80 to blinded NIRS monitoring. The only exclusion criterion was a decision not to provide life support. INTERVENTIONS: Monitoring of cerebral...... oxygenation using NIRS in combination with a dedicated treatment guideline during the first 72 hours of life (experimental) compared with blinded NIRS oxygenation monitoring with standard care (control). MAIN OUTCOME MEASURES: The primary outcome measure was the time spent outside the target range of 55......-85% for cerebral oxygenation multiplied by the mean absolute deviation, expressed in %hours (burden of hypoxia and hyperoxia). One hour with an oxygenation of 50% gives 5%hours of hypoxia. Secondary outcomes were all cause mortality at term equivalent age and a brain injury score assessed by cerebral...

  9. Cerebral autoregulation in the preterm newborn using near-infrared spectroscopy

    DEFF Research Database (Denmark)

    Eriksen, Vibeke R; Hahn, Gitte H; Greisen, Gorm

    2015-01-01

    The aim was to compare two conventional methods used to describe cerebral autoregulation (CA): frequency-domain analysis and time-domain analysis. We measured cerebral oxygenation (as a surrogate for cerebral blood flow) and mean arterial blood pressure (MAP) in 60 preterm infants. In the frequency...

  10. Cerebral Palsy: General Information. Fact Sheet Number 2 = La Paralisis Cerebral: Informacion General. Fact Sheet Number 18.

    Science.gov (United States)

    Interstate Research Associates, McLean, VA.

    This fact sheet on cerebral palsy is offered in both English and Spanish. First, it provides a definition and considers various causes (e.g., an insufficient amount of oxygen reaching the fetal or newborn brain). The fact sheet then offers incidence figures and explains characteristics of the three main types of cerebral palsy: spastic, athetoid,…

  11. Oxygen Transport to Human Tissues.

    Science.gov (United States)

    1981-06-01

    by Bio-Tech, Inc., the New Mexico Lung Association, and the Maria Teresa Restaurant was also most helpful. We are also indebted to individuals who...pH was somehow better regulated than was blood pH. Kellogg introduced us to the White Mountain Laboratory, east of the Sierras , which was built in

  12. Continuous Selective Intra-Arterial Application of Nimodipine in Refractory Cerebral Vasospasm due to Aneurysmal Subarachnoid Hemorrhage

    Directory of Open Access Journals (Sweden)

    Stephanie Ott

    2014-01-01

    Full Text Available Background. Cerebral vasospasm is one of the leading courses for disability in aneurysmal subarachnoid hemorrhage. Effective treatment of vasospasm is therefore one of the main priorities for these patients. We report about a case series of continuous intra-arterial infusion of the calcium channel antagonist nimodipine for 1–5 days on the intensive care unit. Methods. In thirty patients with aneurysmal subarachnoid hemorrhage and refractory vasospasm continuous infusion of nimodipine was started on the neurosurgical intensive care unit. The effect of nimodipine on brain perfusion, cerebral blood flow, brain tissue oxygenation, and blood flow velocity in cerebral arteries was monitored. Results. Based on Hunt & Hess grades on admission, 83% survived in a good clinical condition and 23% recovered without an apparent neurological deficit. Persistent ischemic areas were seen in 100% of patients with GOS 1–3 and in 69% of GOS 4-5 patients. Regional cerebral blood flow and computed tomography perfusion scanning showed adequate correlation with nimodipine application and angiographic vasospasm. Transcranial Doppler turned out to be unreliable with interexaminer variance and failure of detecting vasospasm or missing the improvement. Conclusion. Local continuous intra-arterial nimodipine treatment for refractory cerebral vasospasm after aSAH can be recommended as a low-risk treatment in addition to established endovascular therapies.

  13. Sympathetic influence on cerebral blood flow and metabolism during exercise in humans

    DEFF Research Database (Denmark)

    Seifert, Thomas; Secher, Niels H

    2011-01-01

    This review focuses on the possibility that autonomic activity influences cerebral blood flow (CBF) and metabolism during exercise in humans. Apart from cerebral autoregulation, the arterial carbon dioxide tension, and neuronal activation, it may be that the autonomic nervous system influences CBF......, but increases during cycling exercise. The increase in CMRO(2) is unaffected by beta-adrenergic blockade even though CBF is reduced suggesting that cerebral oxygenation becomes critical and a limited cerebral mitochondrial oxygen tension may induce fatigue. Also, sympathetic activity may drive cerebral non...

  14. Inconsistent detection of changes in cerebral blood volume by near infrared spectroscopy in standard clinical tests.

    Science.gov (United States)

    Canova, D; Roatta, S; Bosone, D; Micieli, G

    2011-06-01

    The attractive possibility of near infrared spectroscopy (NIRS) to noninvasively assess cerebral blood volume and oxygenation is challenged by the possible interference from extracranial tissues. However, to what extent this may affect cerebral NIRS monitoring during standard clinical tests is ignored. To address this issue, 29 healthy subjects underwent a randomized sequence of three maneuvers that differently affect intra- and extracranial circulation: Valsalva maneuver (VM), hyperventilation (HV), and head-up tilt (HUT). Putative intracranial ("i") and extracranial ("e") NIRS signals were collected from the forehead and from the cheek, respectively, and acquired together with cutaneous plethysmography at the forehead (PPG), cerebral blood velocity from the middle cerebral artery, and arterial blood pressure. Extracranial contribution to cerebral NIRS monitoring was investigated by comparing Beer-Lambert (BL) and spatially resolved spectroscopy (SRS) blood volume indicators [the total hemoglobin concentration (tHb) and the total hemoglobin index, (THI)] and by correlating their changes with changes in extracranial circulation. While THIe and tHbe generally provided concordant indications, tHbi and THIi exhibited opposite-sign changes in a high percentage of cases (VM: 46%; HV: 31%; HUT: 40%). Moreover, tHbi was correlated with THIi only during HV (P < 0.05), not during VM and HUT, while it correlated with PPG in all three maneuvers (P < 0.01). These results evidence that extracranial circulation may markedly affect BL parameters in a high percentage of cases, even during standard clinical tests. Surface plethysmography at the forehead is suggested as complementary monitoring helpful in the interpretation of cerebral NIRS parameters.

  15. In vivo determination of cerebral hemodynamics and bioenergetics using spin-echo magnetic resonance imaging

    Science.gov (United States)

    Oja, Joni Marcus Eric

    1999-08-01

    It is well known that the transverse relaxation time, T 2, is dependent on the oxygenation state of blood. Two biophysical mechanisms have been proposed to explain this interdependency. In the diffusion model, oxygenation effects are accounted for by water diffusion through field gradients inside and outside, of the erythrocytes, whereas in the exchange model, the oxygenation effect is thought to be due to the exchange of water between erythrocytes and plasma. Careful in vitro studies with blood have shown that the exchange model fits best to the obtained data in preference to the diffusion model. During brain activation, local increases in blood flow exceed the oxygen demand, resulting in less deoxygenated blood in the capillary and venous compartments. Due to this, blood is less paramagnetic in these activated brain regions, lengthening T2, which in turn increases the signal intensities of the corresponding voxels in the MR image. Thus the measured blood-oxygen-level-dependent (BOLD) image contrast is a complex function of many physiological parameters, such as tissue morphometry, blood volume, blood flow, oxygenation and oxygen metabolism. All of these parameters contribute to the tissue magnetization influencing the transverse relaxation rate. Until now, no exact equations have been available which would relate these hemodynamic variables to a single MRI observable parameter, namely T 2, in a manner in which absolute units can be used. A fundamental theory was developed to explain measured spin-echo BOLD effects, and it was tested in animals and humans. In animal studies, blood oxygenation was altered by regulating arterial oxygen or carbon dioxide tension. This resulted in changes in blood volume, flow and blood magnetization, which in turn was reflected in T2. Using analytical expressions derived from the theory, the transverse relaxation rate was related to the oxygen saturation and extraction and quantification of microvascular cerebral blood volume was

  16. Effects of ketamine, midazolam, thiopental, and propofol on brain ischemia injury in rat cerebral cortical slices

    Institute of Scientific and Technical Information of China (English)

    Qing-shengXUE; Bu-weiYU; Ze-jianWANG; Hong-zhuanCHEN

    2004-01-01

    AIM: To compare the effects of ketamine, midazolam, thiopental, and propofol on brain ischemia by the model of oxygen-glucose deprivation (OGD) in rat cerebral cortical slices. METHODS: Cerebral cortical slices were incu-bated in 2 % 2,3,5-triphenyltetrazolium chloride (TTC) solution after OGD, the damages and effects of ketamine,midazolam, thiopental, and propofol were quantitativlye evaluated by ELISA reader of absorbance (A) at 490 nm,which indicated the red formazan extracted from slices, lactic dehydrogenase (LDH) releases in the incubated supernate were also measured. RESULTS: Progressive prolongation of OGD resulted in decreases of TTC staining.The percentage of tissue injury had a positive correlation with LDH releases, r=0.9609, P<0.01. Two hours of reincubation aggravated the decrease of TTC staining compared with those slices stained immediately after OGD(P<0.01). These four anesthetics had no effects on the TTC staining of slices. Ketamine completely inhibited thedecrease of A value induced by 10 min of OGD injury. High concentrations of midazolam (10 μmol/L) and thiopental (400μmol/L) partly attenuated this decrease. Propofol at high concentration (100 μmol/L) enhanced the decrease of A value induced by 10 min of OGD injury (P<0.01). CONCLUSION; Ketamine, high concentration of midazolam and thiopental have neuroprotective effects against OGD injury in rat cerebral cortical slices, while high concentration of propofol augments OGD injury in rat cerebral cortical slices.

  17. The Effects of Acupuncture on Cerebral and Muscular Microcirculation: A Systematic Review of Near-Infrared Spectroscopy Studies

    Directory of Open Access Journals (Sweden)

    Ming-Yu Lo

    2015-01-01

    Full Text Available Acupuncture produces physiological effects via stimulating acupoints, proximal or distal to the region of effect. Near-infrared spectroscopy (NIRS noninvasively measures tissue-level hemodynamics in real time. We review the literature investigating the effect of acupuncture on muscular and/or cerebral microcirculation. As the basis, we queried PubMed in June 2014 for articles mentioning both acupuncture and NIRS in title/abstract. The reviewed papers investigated either cerebral (n = 11 or muscular hemodynamics (n = 5 and, based on STRICTA for reporting acupuncture methodology, were overall poor in quality. Acupuncture was found to influence regional oxygen saturation in cerebral and muscular tissue. The cortical response in healthy subjects varied across studies. For subjects with stroke or cerebrovascular dementia, findings suggest that acupuncture may modulate dysfunction in cerebral autoregulation. The muscular response to pressure techniques was more intense than that to needling or laser. Probe proximity could impact measurement sensitivity. No one study simultaneously investigated the direct and remote responses. Research utilizing NIRS to investigate the hemodynamics of acupuncture presently lacks in scope and quality. Improved designs, for example, placebo-controlled, randomized trials, and standardized intervention reporting will raise study quality. Exploiting NIRS in clinical settings, such as stroke, migraine, or other pain conditions, is worthwhile.

  18. Glycopyrrolate abolishes the exercise-induced increase in cerebral perfusion in humans

    DEFF Research Database (Denmark)

    Seifert, Thomas; Fisher, James P; Young, Colin N;

    2010-01-01

    Brain blood vessels contain muscarinic receptors that are important for cerebral blood flow (CBF) regulation, but whether a cholinergic receptor mechanism is involved in the exercise-induced increase in cerebral perfusion or affects cerebral metabolism remains unknown. We evaluated CBF and cerebral...... metabolism (from arterial and internal jugular venous O(2), glucose and lactate differences), as well as the middle cerebral artery mean blood velocity (MCA V(mean); transcranial Doppler ultrasound) during a sustained static handgrip contraction at 40% of maximal voluntary contraction (n = 9) and the MCA V...... abolished by glycopyrrolate (P perfusion without affecting the cerebral metabolic rate for oxygen....

  19. [Nitrous compound content in the tissues of the cerebral hemispheres and cerebellum of rats after a flight on the Kosmos-1129 biosatellite].

    Science.gov (United States)

    Kurkina, L M; Tigranian, R A

    1982-01-01

    The content of ammonia, glutamine, urea, glutamic acid, aspartic acid, and GABA was measured to study nitrogen metabolism. Soon after recovery (6-10 hours after recovery) the content of the above compounds in brain tissues increased, except for GABA whose content decreased. Similar but more marked changes were seen in the brain of control rats exposed to a repeated immobilization stress-effect. These changes were still greater in the flight rats exposed to a repeated immobilization stress-effect postflight. It is suggested that the postflight changes of the above parameters of nitrogen metabolism are induced by stress-agents inherent in space flight and recovery.

  20. Mitochondrial Targeted Antioxidant in Cerebral Ischemia.

    Science.gov (United States)

    Ahmed, Ejaz; Donovan, Tucker; Yujiao, Lu; Zhang, Quanguang

    There has been much evidence suggesting that reactive oxygen species (ROS) generated in mitochondria during cerebral ischemia play a major role in programming the senescence of organism. Antioxidants dealing with mitochondria slow down the appearance and progression of symptoms in cerebral ischemia and increase the life span of organisms. The mechanisms of mitochondrial targeted antioxidants, such as SKQ1, Coenzyme Q10, MitoQ, and Methylene blue, include increasing adenosine triphosphate (ATP) production, decreasing production of ROS and increasing antioxidant defenses, providing benefits in neuroprotection following cerebral ischemia. A number of studies have shown the neuroprotective role of these mitochondrial targeted antioxidants in cerebral ischemia. Here in this short review we have compiled the literature supporting consequences of mitochondrial dysfunction, and the protective role of mitochondrial targeted antioxidants.

  1. Oxygen-enhanced MRI for patients with connective tissue diseases: Comparison with thin-section CT of capability for pulmonary functional and disease severity assessment

    Energy Technology Data Exchange (ETDEWEB)

    Ohno, Yoshiharu, E-mail: yosirad@kobe-u.ac.jp [Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Nishio, Mizuho [Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Koyama, Hisanobu [Division of Radiology, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Yoshikawa, Takeshi; Matsumoto, Sumiaki [Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Seki, Shinichiro [Division of Radiology, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Tsubakimoto, Maho [Division of Radiology, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Department of Radiology, Graduate School of Medical Science, University of the Ryukyus, Nakagami-Gun, Okinawa (Japan); Sugimura, Kazuro [Division of Radiology, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan)

    2014-02-15

    Purpose: To prospectively and directly compare oxygen-enhanced (O{sub 2}-enhanced) MRI with thin-section CT for pulmonary functional loss and disease severity assessment in connective tissue disease (CTD) patients with interstitial lung disease (ILD). Materials and methods: Thin-section CT, O{sub 2}-enhanced MRI, pulmonary function test and serum KL-6 were administered to 36 CTD patients with ILD (23 men, 13 women; mean age: 63.9 years) and nine CTD patients without ILD (six men, and three women; mean age: 62.0 years). A relative-enhancement ratio (RER) map was generated from O{sub 2}-enhanced MRI and mean relative enhancement ratio (MRER) for each subject was calculated from all ROI measurements. CT-assessed disease severity was evaluated with a visual scoring system from each of the thin-section CT data. MRER and CT-assessed disease severities of CTD patients with and without ILD were then statistically compared. To assess capability for pulmonary functional loss and disease severity assessment in CTD patients, correlations of MRER and CT-assessed disease severity with pulmonary functional parameters and serum KL-6 in all subjects were statistically determined. Results: MRER and CT-assessed disease severity showed significant differences between CTD patients with (MRER: 0.15 ± 0.08, CT-assessed disease severity: 13.0 ± 7.4%) and without ILD (MRER: 0.25 ± 0.06, p = 0.0011; CT-assessed disease severity: 1.6 ± 1.6%, p < 0.0001). MRER and CT-assessed disease severity correlated significantly with pulmonary functional parameters and serum KL-6 in all subjects (0.61 ≤ r ≤ 0.79, p < 0.05). Conclusion: O{sub 2}-enhanced MRI was found to be as useful as thin-section CT for pulmonary functional loss and disease severity assessment of CTD patients with ILD.

  2. The effect of NMDA-R antagonism on simultaneously acquired local field potentials and tissue oxygen levels in the brains of freely-moving rats.

    Science.gov (United States)

    Kealy, John; Commins, Sean; Lowry, John P

    2017-01-11

    Non-competitive NMDA receptor antagonists are known to induce psychosis-like symptoms in rodents. Administration of such compounds cause behavioural effects such as memory impairment and hyperlocomotion. Additionally, drugs such as phencyclidine (PCP), ketamine and MK-801 all cause distinctive increases in striatal local field potential (LFP) in the high frequency oscillation (HFO) band in the power spectrum (140-180 Hz). Amperometric sensors provide a means to measure tissue oxygen (tO2; a BOLD-like signal) in the brains of freely-moving rats while simultaneously acquiring LFP using the same electrode. Carbon paste electrodes were implanted into the striatum and hippocampus of male Wistar rats. Rats were administered with saline, ketamine (10 mg/kg), MK-801 (0.1 mg/kg) and PCP (2.5 mg/kg) and recordings were made at 1 kHz using three different potentials (-650 mV to measure tO2; 0 mV and +700 mV as control conditions). NMDA receptor antagonism caused significant increases in tO2 in both the striatum and the hippocampus. Power spectrum analysis showed significant increases in HFO power in the striatum but not in the hippocampus. Conversely, there were significant decreases in delta and alpha power along with increases in theta and gamma power in the hippocampus that were absent in the striatum. This supports findings that LFP can be obtained from an amperometric sensor signal; allowing simultaneous acquisition of two translational biomarkers of neuronal activity (LFP and tO2).

  3. Cerebral angiography

    Science.gov (United States)

    ... highlight any blockages in blood flow. Sometimes, a computer removes the bones and tissues on the images ... M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health ...

  4. Fiber-based hybrid probe for non-invasive cerebral monitoring in neonatology

    Science.gov (United States)

    Rehberger, Matthias; Giovannella, Martina; Pagliazzi, Marco; Weigel, Udo; Durduran, Turgut; Contini, Davide; Spinelli, Lorenzo; Pifferi, Antonio; Torricelli, Alessandro; Schmitt, Robert

    2015-07-01

    Improved cerebral monitoring systems are needed to prevent preterm infants from long-term cognitive and motor restrictions. Combining advanced near-infrared diffuse spectroscopy measurement technologies, time-resolved spectroscopy (TRS) and diffuse correlation spectroscopy (DCS) will introduce novel indicators of cerebral oxygen metabolism and blood flow for neonatology. For non-invasive sensing a fiber-optical probe is used to send and receive light from the infant head. In this study we introduce a new fiber-based hybrid probe that is designed for volume production. The probe supports TRS and DCS measurements in a cross geometry, thus both technologies gain information on the same region inside the tissue. The probe is highly miniaturized to perform cerebral measurements on heads of extreme preterm infants down to head diameters of 6cm. Considerations concerning probe production focus on a reproducible accuracy in shape and precise optical alignment. In this way deviations in measurement data within a series of probes should be minimized. In addition to that, requirements for clinical use like robustness and hygiene are considered. An additional soft-touching sleeve made of FDA compatible silicone allows for a flexible attachment with respect to the individual anatomy of each patient. We present the technical concept of the hybrid probe and corresponding manufacturing methods. A prototype of the probe is shown and tested on tissue phantoms as well as in vivo to verify its operational reliability.

  5. Effect of cerebral lymphatic block on cerebral morphology and cortical evoked potential in rats

    Institute of Scientific and Technical Information of China (English)

    Zuoli Xia; Baoling Sun; Mingfeng Yang; Dongmei Hu; Tong Zhao; Jingzhong Niu

    2006-01-01

    BACKGROUND: It has been shown that although brain does not contain lining endothelial lymphatic vessel,it has lymphatic drain.Anterior lymphatic vessel in brain tissue plays a key role in introducing brain interstitial fluid to lymphatic system;however,the significance of lymphatic drain and the affect on cerebral edema remains unclear.OBJECTIVE: To investigate the effect of cerebral lymphatic block on cerebral morphology and cortical evoked potential in rats.DESIGN: Randomized controlled animal study.SETTING: Institute of Cerebral Microcirulation of Taishan Medical College and Department of Neurology of Affiliated Hospital.MATERIALS:A total of 63 healthy adult male Wistar rats weighing 300-350 g were selected in this study.Forty-seven rats were used for the morphological observation induced by lymphatic drain and randomly divided into three groups:general observation group(n=12),light microscopic observation group(n=21)and electronic microscopic observation group(n=14).The rats in each group were divided into cerebral lymphatic block subgroup and sham-operation control subgroup.Sixteen rats were divided into cerebral the effect of cerebral lymphatic block on cortical evoked potential,in which the animals were randomly divided into sham-operation group(n=6)and cerebral lymphatic block group(n=10).METHODS:The experiment was carried out in the Institute of Cerebral Microcirculation of Taishan Medical College from January to August 2003.Rats in cerebral lymphatic block group were anesthetized and separated bilateral superficial and deep cervical lymph nodes under sterile condition. Superior and inferior boarders of lymph nodes were ligated the inputting and outputting channels, respectively, and then lymph node was removed so as to establish cerebral lymphatic drain disorder models. Rats in sham-operation control group were not ligated the lymphatic vessel and removed lymph nodes.and other operations were as the same as those in cerebral lymphatic block group

  6. Cerebral toxoplasmosis in AIDS

    Energy Technology Data Exchange (ETDEWEB)

    Christ, F.; Steudel, H.; Klotz, D.

    1986-02-01

    Since 1982 (Hauser and co-workers), literature has reported focal cerebral tissue charges in AIDS patients whose diagnosis was unclear at first but which could be identified finally as florid toxoplasmosis encephalitis by biopsy and autopsy. It was found that the value of otherwise reliable serological tests (KBR, Sabin-Feldmann tests, etc.) is questionable in patients with severely impaired or incompetent immune systems, and, in particular, that a negative or uncharacteristic test result may not preclude any opportunistic infection process. Furthermore, isolation of Toxoplasma gondii or specific antibodies from the cerebrospinal fluid will be successful in exceptional cases only. In patients with AIDS or lymphadenopathy syndrome, the differential diagnosis will have to include - first and foremost - reactivated toxoplasma infection (not newly acquired, as a rule) if central neurological symptoms occur.

  7. Brain oxygen saturation assessment in neonates using T2-prepared blood imaging of oxygen saturation and near-infrared spectroscopy.

    Science.gov (United States)

    Alderliesten, Thomas; De Vis, Jill B; Lemmers, Petra Ma; Hendrikse, Jeroen; Groenendaal, Floris; van Bel, Frank; Benders, Manon Jnl; Petersen, Esben T

    2017-03-01

    Although near-infrared spectroscopy is increasingly being used to monitor cerebral oxygenation in neonates, it has a limited penetration depth. The T2-prepared Blood Imaging of Oxygen Saturation (T2-BIOS) magnetic resonance sequence provides an oxygen saturation estimate on a voxel-by-voxel basis, without needing a respiratory calibration experiment. In 15 neonates, oxygen saturation measured by T2-prepared blood imaging of oxygen saturation and near-infrared spectroscopy were compared. In addition, these measures were compared to cerebral blood flow and venous oxygen saturation in the sagittal sinus. A strong linear relation was found between the oxygen saturation measured by magnetic resonance imaging and the oxygen saturation measured by near-infrared spectroscopy ( R(2 )= 0.64, p infrared spectroscopy oxygen saturation, and magnetic resonance imaging measures of frontal cerebral blood flow, whole brain cerebral blood flow and venous oxygen saturation in the sagittal sinus ( R(2 )= 0.71, 0.50, 0.65; p infrared spectroscopy and T2-prepared blood imaging of oxygen saturation, confirming the validity of using of these techniques for determining cerebral oxygenation.

  8. Oxygen Therapy

    Science.gov (United States)

    Oxygen therapy is a treatment that provides you with extra oxygen. Oxygen is a gas that your body needs to function. Normally, your lungs absorb oxygen from the air you breathe. But some conditions ...

  9. The Clinical Study on Relation between Regional Cerebral Oxygen Saturation and Postoperative Delirium in Patients during Cardiopulmonary Bypass%体外循环术中局部脑氧饱和度与术后谵妄的关系

    Institute of Scientific and Technical Information of China (English)

    刘威; 齐娟; 于荣国; 姚祖武; 龚书榕; 顾恩郁

    2011-01-01

    Objective To study the relation between regional cerebral oxygen saturation (rScO2)and postoperative delirium in patients underwent cardiopulmonary bypass (CPB) of cardiac surgery.Methods Twenty-eight patients underwent elective cardiac surgery were enrolled in the study. Postoperative delirium was assessed by the CAM-ICU everyday during 7 days after operation. All of the patients were divided into two groups (delirium group and non-delirium group) based on the postoperative delirium. The rScO2 of all patients was monitored during operation. The value of the mean rScO2 in the 7 periods (preoperatiion, preinducement, from inducement to the beginning of CPB, from the beginning of CPB to the end of nose temperature cooling, from the end of nose temperature cooling to the beginning of warming, from the beginning of warming to the end of CPB, the 30 minutes after CPB) during the operation period were calculated. The area under the curve of the rScO2 was calculated. Results The AUC-rScO2 of the patients in delirium group was significantly larger than the non-delirium group (P<0.05).Conclusions The low rScO2 increases the postoperative delirium in patients who underwent cardiopulmonary bypass of cardiac surgery. Hence we should monitor the rScO2 during operation.%目的 探讨体外循环(CPB)心血管外科手术期间患者脑氧代谢与术后谵妄的关系.方法 收集择期行CPB下心内直视手术患者28例,术后7 d内,每日以ICU精神错乱评估量表(CAM-ICU)评估患者的精神状态,以是否发生谵妄分为谵妄组和非谵妄组.2组术中均以近红外光谱仪动态监测监测局部脑氧饱和度(rScO2),计算围手术期中7个时段(术前、诱导前、诱导至CPB前、CPB开始至鼻咽温降温末、鼻咽温降温末至复温初、复温初至CPB结束、CPB结束后30 min)rScO2均值;计算rScO2曲线下面积(AUC-rScO2).结果 谵妄组AUC-rScO2较非谵妄组增大(P<0.05).结论 心血管外科手术CPB期间患者出现低rScO2

  10. Different routes of administration of human umbilical tissue-derived cells improve functional recovery in the rat after focal cerebral ischemia.

    Science.gov (United States)

    Zhang, Li; Li, Yi; Romanko, Michael; Kramer, Brian C; Gosiewska, Anna; Chopp, Michael; Hong, Klaudyne

    2012-12-13

    Human umbilical tissue-derived cells (hUTC) are a potential neurorestorative candidate for stroke treatment. Here, we test the effects of hUTC treatment in a rat model of stroke via various routes of administration. Rats were treated with hUTC or phosphate-buffered saline (PBS) via different routes including intraarterial (IA), intravenous (IV), intra-cisterna magna (ICM), lumber intrathecal (IT), or intracerebral injection (IC) at 24h after stroke onset. Treatment with hUTC via IV and IC route led to significant functional improvements starting at day 14, which persisted to day 60 compared with respective PBS-treated rats. HUTC administered via IA, ICM, and IT significantly improved neurological functional recovery starting at day 14 and persisted up to day 49 compared with PBS-treated rats. Although IA administration resulted in the highest donor cell number detected within the ischemic brain compared to the other routes, hUTC treatments significantly increased ipsilateral bromodeoxyuridine incorporating subventricular zone (SVZ) cells and vascular density in the ischemic boundary compared with PBS-treated rats regardless of the route of administration. While rats received hUTC treatment via IA, IV, IC, and ICM routes showed greater synaptophysin immunoreactivity, significant reductions in TUNEL-positive cells in the ipsilateral hemisphere were observed in IA, IV, and IC routes compared with PBS-treated rats. hUTC treatments did not reduce infarct volume when compared to the PBS groups. Our data indicate that hUTC administered via multiple routes provide therapeutic benefit after stroke. The enhancement of neurorestorative events in the host brain may contribute to the therapeutic benefits of hUTC in the treatment of stroke.

  11. Uptake of gamma-aminobutyric acid and L-glutamic acid by synaptosomes from postmortem human cerebral cortex: multiple sites, sodium dependence and effect of tissue preparation.

    Science.gov (United States)

    Dodd, P R; Watson, W E; Morrison, M M; Johnston, G A; Bird, E D; Cowburn, R F; Hardy, J A

    1989-06-26

    The uptake of gamma-aminobutyric acid (GABA) and L-glutamic acid by synaptosomes prepared from frozen postmortem human brain was shown to be effected via distinct high and low affinity sites. At approximately 17 h postmortem delay, the kinetic parameters for GABA uptake were: high affinity site, Km 7.1 +/- 2.5 microM, Vmax 18.7 +/- 4.8 nmol.min-1 per 100 mg protein; low affinity site, Km 2 +/- 1 mM, Vmax 425 +/- 250 nmol.min-1 per 100 mg protein (means +/- S.E.M., n = 13). Kinetic parameters for L-glutamate uptake were: high affinity site, Km 7.5 +/- 1.0 microM, Vmax 85 +/- 8 nmol.min-1 per 100 mg protein; low affinity site, Km 1.8 +/- 1.2 mM. Vmax 780 +/- 175 nmol.min-1 per 100 mg protein (n = 11). A detailed kinetic analysis of high affinity GABA uptake was performed over a range of sodium ion concentrations. The results were consistent with a coupling ratio of one Na+ ion to one GABA molecule; a similar result was found with rat brain synaptosomes. However, rat and human synaptosomes differed in the degree to which the substrate affinity of the high affinity GABA uptake site varied with decreasing Na+ ion concentration. High affinity GABA uptake was markedly affected by the method used to freeze and divide the tissue, but did not vary greatly in different cortical regions. There was some decline of high affinity GABA uptake activity with postmortem delay, apparently due to a loss of sites rather than a change in site affinity.

  12. Employees with Cerebral Palsy

    Science.gov (United States)

    ... problems in the muscles or nerves. Instead, faulty development or damage to motor areas in the brain disrupt the brain's ability to adequately control movement and posture (United Cerebral Palsy, 2010). "Cerebral" refers to the ...

  13. United Cerebral Palsy

    Science.gov (United States)

    ... be sure to follow us on Twitter . United Cerebral Palsy UCP educates, advocates and provides support services to ... Partners Merz Logo Sprint Relay Copyright © 2015 United Cerebral Palsy 1825 K Street NW Suite 600 Washington, DC ...

  14. Case Report: Emergency awake craniotomy for cerebral abscess in a patient with unrepaired cyanotic congenital heart disease

    Science.gov (United States)

    Fassl, Jens; Tobler, Daniel; Zumofen, Daniel; Steiner, Luzius A.; Goettel, Nicolai

    2017-01-01

    We report the case of a 39-year-old male with complex cyanotic congenital heart disease undergoing emergency craniotomy for a cerebral abscess. Maintenance of intraoperative hemodynamic stability and adequate tissue oxygenation during anesthesia may be challenging in patients with cyanotic congenital heart disease. In this case, we decided to perform the surgery as an awake craniotomy after interdisciplinary consensus. We discuss general aspects of anesthetic management during awake craniotomy and specific concerns in the perioperative care of patients with congenital heart disease. PMID:27928498

  15. AQP4 expression of the cerebral ischemic tissue following its mRNA silence in rat%基因沉默对缺血脑组织水通道蛋白4表达的影响

    Institute of Scientific and Technical Information of China (English)

    鲁宏; 胡惠; 何占平; 涂蓉; 舒庆杰

    2012-01-01

    To investigate the effect of RNA interference targeting AQP4 on its expression in the cerebral ischemic tissues. Methods: Total 108 Wistar rats were divided into three groups randomly: ischemic groups (MCAO), control group (shRNA-AQP4 + MCAO) and interference groups (siRNA-AQP4 + MCAO). Each group was subdivided into six sub groups according to the different interval of time points: 0. 25 h, 0. 5 h, 1 h, 2 h, 4 h and 6 h (n = 6 for each group). The right middle cerebral artery of rats was unilaterally occluded (MCAO) in ischemic groups. The reagent including nonsense short hairpin (shRNA) liposomes and short interference (siRNA)-AQP4 liposomes were injected to the right basal ganglia of the rats of MCAO served as a control group and an interference group, respectively. The animals were sacrificed and per fused with the mixture solution consisting formalin. The right basal ganglia tissues were examined with pathology, immuno histochemistry, real time fluorescence quantitative reverse transcript polymerase chain reaction (RT-PCR) and Western blot ting. Results: There was no significant change in AQP4 expression between the control group and the ischemic group. The expression of AQP4 increased rapidly within 2 h, and then increased slowly during 4-6 h. Whereas, there was no significant change in AQP4 expression between the control group and the interference group at 0. 25 h and 6 h after MCAO. But there was significant change in AQP4 expression between the control group and the interference group during 0. 5-4 h. The AQP4 expression could be inhibited efficiently by RNA silencing technique during 0. 5-4 h, but it became unconspicuous during 4-6 h. The corresponding histological changes within 4 h were intracellular edema in the ischemic group and the control group, but this pathological change was obviously mitigated in the interference group during the same period of time. With the pro gress of the time (4-6 h), The vasogenic brain edema was mostly observed in

  16. Blood oxygenation level dependent effect of cerebral ischemic penumbra in monkey reversible middle cerebral artery occlusion model%猴可复性大脑中动脉闭塞模型脑缺血半暗带的血氧水平依赖效应

    Institute of Scientific and Technical Information of China (English)

    张敬; 陈英敏; 张云亭

    2010-01-01

    Objective To investigate the value of blood oxygenation level dependent (BOLD) MRI in detecting monkey cerebral ischemic penumbra (IP). Methods Six monkeys were used to make reversible middle cerebral artery occlusion (MCAO) model by an interventional microcatheter method. MR DWI, PWI mean transit time (MTT), T_2WI and quantitative T_2 map, T_2~* map were performed at MCAO (0 h) and 1,3,6,12,24,48 h after reperfusion. Reversible transverse relaxation rate (R_2') BOLD imaging was calculated using quantitative T_2 and T_2~* maps. Lesion volume percentage (lesion volume/bilateral hemispheres volume) were measured on 0 h DWI,48 h T_2WI and TTC staining. Ischemic area was subdivided into infracted core (high signal area on both 0 h DWI and 48 h T_2 WI), IP (high signal on 0 h DWI, iso on 48 h T_2 WI) and oligemia (0 h delayed MTT, iso signal on both 0 h DWI and 48 h T_2 WI). Relative R_2' (rR_2') was calculated to get ratio between the lesion and mirror area in contralateral healthyhemisphere. Paired t test and correlation analysis were used for comparison of lesion volume percentage. rR_2' values at each time point were compared by ANOVA. Results Reversible MCAO models were made successfully in 4 of 6 monkeys. Lesion volume porcentage on 48 h T_2 WI was reduced compared to that on Oh DWI [ (8.16±0.55)% vs (11.37±1.41)% ,t=6.472,P0.05], which showed significant positive correlation (r=0.98, P0.05),两者呈明显正相关(r=0.98,P<0.05).梗死核心、IP、低灌注区rR_2'在各时间点差异均有统计学意义,梗死核心低于IP,IP低于低灌注区(P<0.05),三者rR_2'值:0 h时分别为1.129±0.108、1.329±0.081、1.584±0.103(F=36.19,P<0.05).1 h分别为0.668±0.082、1.237±0.072、1.435±0.066(F=134.09,P<0.05).3 h分别为0.536±0.075、1.453±0.081、1.770±0.141(F=256.30,P<0.05).6 h分别为0.259±0.050、2.435±0.131、2.957±0.177(F=803.25,P<0.05).12 h分别为0.385±0.054、2.447±0.148、3.254±0.184(F=743.74,P<0.05).24 h分别为0.083±0.026、1

  17. Effect of hyperbaric oxygen preconditioning on expression of neuroplasticity after acute global cerebral ischemia-reperfusion in aged rats%高压氧预处理对老龄大鼠全脑缺血再灌注损伤后神经可塑性的影响

    Institute of Scientific and Technical Information of China (English)

    邹磊; 刘丹彦; 殷薇; 宋云

    2014-01-01

    Objective To investigate the effect of hyperbaric oxygen preconditioning (HOP)on expression of Nogo mRNA,No-go-A and Ng R protein in the cerebral cortex after acute global cerebral ischemia-reperfusion (I/R)in aged rats and to study its mechanism affecting neuroplasticity.Methods Forty-two aged male SD rats were randomly divided into 4 groups:control group (C group,n=6),hyperbaric oxygen group (H group,n=12),cerebral I/R injury group (I/R group,n=12)and HOP group (n=12). The H group and the HOP group were placed in the hyperbaric oxygen cabin for 1 h per day with a oxygen pressure of 0.2 Mpa for successive 5 d,at 24 h after last time of hyperbaric oxygen preconditioning the I/R group and the HOP group adopted the modified Pulsinelli vessel occlusion method for preparing the rat I/R injury model,with global cerebral ischemia for 10 min and reperfusion for 24 h,each 6 rats were randomly taken from the the H group,I/R group and HOP group and their heads were cut off for taking the brain and isolating the cerebral cortex.The real time fluorescence quantification PCR was adopted to detect the expression level of Nogo mRNA and the Nogo-A protein level was detected by Western blot.The rats in various groups were performed the T1 WI and T2WI scanning in the transection position and the coronal positions.Results There were no obvious ischemic brain infarction in the normal control group and the H group,the arc-shaped bilateral cortex ischemic infarct area was clearly seen in the ischemic group,the ischemic infarct area was also seen in the HOP ischemia group,but its area was smaller than which in the ischemic group.Compared with the C group,the expression of Nogo mRNA and the Nogo-A protein in the HOP group was up-regulated(P<0.05);compared with the I/R group,the expression of Nogo mRNA and the Nogo-A protein was down-regulated(P<0.05). Conclusion HOP increases the neuroplasticity and can reduce the cerebral ischemic infarction area in the exceed acute stage of rat acute

  18. Cerebral blood flow during cardiopulmonary bypass in pediatric cardiac surgery: the role of transcranial Doppler – a systematic review of the literature

    Directory of Open Access Journals (Sweden)

    Sanders Stephen P

    2006-12-01

    Full Text Available Abstract Background Transcranial Doppler Ultrasound (TCD is a sensitive, real time tool for monitoring cerebral blood flow velocity (CBFV. This technique is fast, accurate, reproducible and noninvasive. In the setting of congenital heart surgery, TCD finds application in the evaluation of cerebral blood flow variations during cardiopulmonary bypass (CPB. Methodology We performed a search on human studies published on the MEDLINE using the keyword "trans cranial Doppler" crossed with "pediatric cardiac surgery" AND "cardio pulmonary by pass", OR deep hypothermic cardiac arrest", OR "neurological monitoring". Discussion Current scientific evidence suggests a good correlation between changes in cbral blood flow and mean cerebral artery (MCA blood flow velocity. The introduction of Doppler technology has allowed an accurate monitorization of cerebral blood flow (CBF during circulatory arrest and low-flow CPB. TCD has also been utilized in detecting cerebral emboli, improper cannulation or cross clamping of aortic arch vessels. Limitations of TCD routine utilization are represented by the need of a learning curve and some experience by the operators, as well as the need of implementing CBF informations with, for example, data on brain tissue oxygen delivery and consumption. Conclusion In this light, TCD plays an essential role in multimodal neurological monitorization during CPB (Near Infrared Spectroscopy, TCD, processed electro encephalography that, according to recent studies, can help to significantly improve neurological outcome after cardiac surgery in neonates and pediatric patients.

  19. RELATIONS OF THE CEREBRAL OXYGEN METABOLISM AND THE COGNITIVE FUNCTION AFTER COMBINED DEXMEDETOMIDINE ANESTHESIA OPERATION IN ELDERLY PATIENTS%右美托咪定联合全麻下老年患者术后认知功能与脑氧代谢的关系

    Institute of Scientific and Technical Information of China (English)

    吕安庆; 陈文迪

    2012-01-01

    目的 探讨右美托咪定联合全麻下老年患者术后认知功能与脑氧代谢的关系.方法 选取2009年12月-2011年6月期间在全身麻醉下行手术的老年患者100例,美国麻醉医师协会分级Ⅰ~Ⅲ级.随机分为2组,治疗组和对照组,各50例,采用简易智力状态检查表(mini-mental state examination,MMSE)对比评估2组患者术后6h,1、3d的认知功能.2组于麻醉诱导后即刻(T0 )、麻醉后60min(T1) 和麻醉恢复时(T2) 同步采集桡动脉和颈内静脉球部血样行血气分析,根据血红蛋白(hemoglobin,Hb)、动脉血氧饱和度(arterial oxygen saturation,SaO2)、颈内静脉血氧饱和度(jugular venous oxygen saturation,SjvO2)、动脉血氧分压(arterial partial prussure of oxygen,PaO2) 和颈内静脉血氧分压(jugular venous oxygen partial pressure,PjvO2),计算脑血流量/脑氧代谢率比值(cerebral blood flow to cerebral metabolic rate for oxygen,CBF/CMRO2).结果 手术后6h、1d各组MMSE评分均有不同程度的降低(P<0.05);手术后6h、1d A组MMSE评分明显低于B组(P<0.05);A组T0和T1时,CBF/CMR02异常发生率明显降低,差异有统计学意义(P<0.05); Logistic逐步回归分析显示T1时CBF/CMRO2异常与老年患者术后认知功能障碍的发生有关(β=3.413,P<0.05).结论 全麻下老年患者脑氧代谢异常可能是认知功能障碍的诱导原因之一,右美托咪定可能通过调节脑氧代谢功能来改善术后认知功能.%Objective To investigate the relations of the cerebral oxygen metabolism and the cognitive function after combined dexmedetomidine anesthesia operation in elderly patients. Methods One hundred patients aged over 60 years old were randomly divided into two groups: treatment group ( n = 50 ) and control group ( n = 50 ). A battery of mini - mental state examination ( MMSE ) and neuropsychological tests were administered 6 hours, 1 day and 7 days after surgery. Blood samples were taken from artery and internal jugular

  20. Cerebral microangiopathies; Zerebrale Mikroangiopathien

    Energy Technology Data Exchange (ETDEWEB)

    Linn, Jennifer [Klinikum der Universitaet Muenchen (Germany). Abt. fuer Neuroradiologie

    2011-03-15

    Cerebral microangiopathies are a very heterogenous group of diseases characterized by pathological changes of the small cerebral vessels. They account for 20 - 30 % of all ischemic strokes. Degenerative microangiopathy and sporadic cerebral amyloid angiography represent the typical acquired cerebral microangiopathies, which are found in over 90 % of cases. Besides, a wide variety of rare, hereditary microangiopathy exists, as e.g. CADASIL (Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy), Fabrys disease and MELAS syndrome (Mitochondrial myopathy, Encephalopathy, Lactic Acidosis, and Stroke-like episodes). (orig.)

  1. Sesamin attenuates behavioral, biochemical and histological alterations induced by reversible middle cerebral artery occlusion in the rats.

    Science.gov (United States)

    Khan, Mohd Moshahid; Ishrat, Tauheed; Ahmad, Ajmal; Hoda, Md Nasrul; Khan, M Badruzzaman; Khuwaja, Gulrana; Srivastava, Pallavi; Raza, Syed Shadab; Islam, Fakhrul; Ahmad, Saif

    2010-01-05

    Restoration of blood flow to an ischemic brain region is associated with generation of reactive oxygen species (ROS) with consequent reperfusion injury. ROS cause lipid peroxidation, protein oxidation, and DNA damage, all of which are deleterious to cells. So diminishing the production of free radicals and scavenging them may be a successful therapeutic strategy for the protection of brain tissue in cerebral stroke. The present study investigated the neuroprotective effect of sesamin (Sn) to reduce brain injury after middle cerebral artery occlusion (MCAO). The middle cerebral artery (MCA) of adult male Wistar rat was occluded for 2h and reperfused for 22h. Sesamin is the most abundant lignan in sesame seed oil is a potent antioxidant. Sesamin (30 mg/kg) was given orally twice, 30 min before the onset of ischemia and 12h after reperfusion. The initial investigations revealed that sesamin reduced the neurological deficits in terms of behavior and reduced the level of thiobarbituric acid reactive species (TBARS), and protein carbonyl (PC) in the different areas of the brain when compared with the MCAO group. A significantly depleted level of glutathione and its dependent enzymes (glutathione peroxidase [GPx] and glutathione reductase [GR]) in MCAO group were protected significantly in MCAO group treated with sesamin. The present study suggests that sesamin may be able to attenuate the ischemic cell death and plays a crucial role as a neuroprotectant in regulating levels of reactive oxygen species in the rat brain. Thus, sesamin may be a potential compound in stroke therapy.

  2. Monitoring the oxygenation of the preterm brain : What is there to gain?

    NARCIS (Netherlands)

    Alderliesten, T.

    2016-01-01

    Despite advances in perinatal care, preterm birth is still associated with adverse neurodevelopmental outcome, often caused by cerebral injury. The most common forms of cerebral injury are all associated with disturbances in cerebral oxygen and blood supply. Traditionally, infant wellbeing is evalua