WorldWideScience

Sample records for clearance

  1. Security Clearance Tracking System

    Data.gov (United States)

    National Archives and Records Administration — SCTS supports the adjudication process of private background investigations and clearances for potential employees, contractors, interns and student workers.

  2. Generic Clearance Values

    International Nuclear Information System (INIS)

    This paper analyzes the Generic Clearance Values established for natural and artificial radionuclides with the objective of evaluating their degree of conservatism in views of adopting them into the regulatory body. Generic clearance values for natural radionuclides have been chosen by experts judgments as the optimum boundary between, on the one hand, the ubiquitous unmodified soil concentrations and, on the other hand, activity concentrations in ores, mineral sands, industrial residues and wastes. For artificial radionuclides the clearance levels have been derived from the scenarios postulated in the document Safety Reports Series 44 of the IAEA considering quantitative exemption criteria. A set of 8 scenarios were postulated covering external, ingestion and inhalation exposure pathways. For each radionuclide, the generic clearance level was derived as the more restrictive value obtained from the scenarios, that is the lowest ratio between the applicable individual dose and the dose per unit activity concentration (Bq/g). The individual dose was calculated by a formula depending on each scenario and pathway, with different parameters, such as exposure time, dosimetric factors, dilution factor, density of the material, geometric factors, etc. It was concluded that the basis and parameters used for the derivation of the generic clearance levels are quite conservative and therefore its the adoption in Argentina has been recommended. It is expected that their implementation will contribute to optimize the regulatory management system. (authors)

  3. Mucociliary clearance in chronic sinusitis

    OpenAIRE

    Birdi, Surinder Mohan; Singh, Sunder; Singh, Ajit

    1998-01-01

    Mucociliary clearance is an important defence mechanism of upper and lower respiratory tracts. Any disturbance in the mechanism leads to stagnation of secretions and secondary infection with prolonged mucociliary clearance time. The present study was undertaken to establish normal mucociliary clearance time in our region and to evaluate its diagnostic and prognostic potential in chronic sinusitis of variable duration with and without obstructive diseases.

  4. Site clearance working group

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    The Gulf of Mexico and Louisiana continue to be areas with a high level of facility removal, and the pace of removal is projected to increase. Regulations were promulgated for the Gulf of Mexico and Louisiana requiring that abandoned sites be cleared of debris that could interfere with fishing and shrimping activities. The site clearance regulations also required verification that the sites were clear. Additionally, government programs were established to compensate fishermen for losses associated with snagging their equipment on oil and gas related objects that remained on the water bottoms in areas other than active producing sites and sites that had been verified as clear of obstructions and snags. The oil and gas industry funds the compensation programs. This paper reviews the regulations and evolving operating practices in the Gulf of Mexico and Louisiana where site clearance and fisherman`s gear compensation regulations have been in place for a number of years. Although regulations and guidelines may be in place elsewhere in the world, this paper focuses on the Gulf of Mexico and Louisiana. Workshop participants are encouraged to bring up international issues during the course of the workshop. Additionally, this paper raises questions and focuses on issues that are of concern to the various Gulf of Mexico and Louisiana water surface and water bottom stakeholders. This paper does not have answers to the questions or issues. During the workshop participants will debate the questions and issues in an attempt to develop consensus opinions and/or make suggestions that can be provided to the appropriate organizations, both private and government, for possible future research or policy adjustments. Site clearance and facility removal are different activities. Facility removal deals with removal of the structures used to produce oil and gas including platforms, wells, casing, piles, pipelines, well protection structures, etc.

  5. Lithium clearance in chronic nephropathy

    DEFF Research Database (Denmark)

    Kamper, A L; Holstein-Rathlou, N H; Leyssac, P P;

    1989-01-01

    1. Lithium clearance measurements were made in 72 patients with chronic nephropathy of different aetiology and moderate to severely reduced renal function. 2. Lithium clearance was strictly correlated with glomerular filtration rate, and there was no suggestion of distal tubular reabsorption of...... lithium or influence of osmotic diuresis. 3. Fractional reabsorption of lithium was reduced in most patients with glomerular filtration rates below 25 ml/min. 4. Calculated fractional distal reabsorption of sodium was reduced in most patients with glomerular filtration rates below 50 ml/min. 5. Lithium...... lithium clearance may be a measure of the delivery of sodium and water from the renal proximal tubule. With this assumption it was found that adjustment of the sodium excretion in chronic nephropathy initially takes place in the distal parts of the nephron (loop of Henle, distal tubule and collecting duct...

  6. Lactate clearance in cardiorespiratory emergency

    Directory of Open Access Journals (Sweden)

    Serena Greco

    2007-08-01

    Full Text Available Early goal directed therapy has been found to improve prognosis in septic patients, if the therapeutic goal is achieved within the first six hours. The aim of our study is to demonstrate that in patients with acute cardiorespiratory failure, rapid (within 2 hours lactate clearance can help define patients’ prognosis. 67 consecutive patients, admitted to our 16-bed Emergency Medicine ward for acute cardiorespiratory failure (age 75,9 ± 9,8 (APACHE II score 19,0 ± 4,1, were included in the study. Blood lactate concentration was read at admission and after 2, 6 and 24 hours. We evaluated mortality at seven days and the use of orotracheal intubation (patients with negative outcome vs. discharge or transfer to a non-emergency ward with subsequent discharge (patients with negative outcome. Lactate concentration at admission was 4,6 ± 2,5 mmol/l; lactate clearance (% at 2 hours was 40,4 ± 32,1 in patients with a positive outcome and –8,3 ± 5,0 in patients with a negative outcome (p < 0,05. Lactate clearance at 2 hours < 25% is correlated to a negative outcome with an 84,2% sensitivity and a 79,2% specificity. The positive predictive value was 61,5% and the negative predictive value was 92,2%. Systematic lactate clearance monitoring can be used in cases of acute cardiorespiratory insufficiency to identify patients with a high risk of negative outcome. In our study, low clearance at two hours was associated with an increase in mortality and/or the need for orotracheal intubation. Conversely, a clearance at two hours of > 25% in most cases confirms the therapeutic strategy undertaken. Serial evaluation of blood lactate concentration may therefore be useful in guiding treatment strategies.

  7. Noninvasive clearance of airway secretions.

    Science.gov (United States)

    Hardy, K A; Anderson, B D

    1996-06-01

    Airway clearance techniques are indicated for specific diseases that have known clearance abnormalities (Table 2). Murray and others have commented that such techniques are required only for patients with a daily sputum production of greater than 30 mL. The authors have observed that patients with diseases known to cause clearance abnormalities can have sputum clearance with some techniques, such as positive expiratory pressure, autogenic drainage, and active cycle of breathing techniques, when PDPV has not been effective. Hasani et al has shown that use of the forced exhalatory technique in patients with nonproductive cough still resulted in movement of secretions proximally from all regions of the lung in patients with airway obstruction. It is therefore reasonable to consider airway clearance techniques for any patient who has a disease known to alter mucous clearance, including CF, dyskinetic cilia syndromes, and bronchiectasis from any cause. Patients with atelectasis from mucous plugs and hypersecretory states, such as asthma and chronic bronchitis, patients with pain secondary to surgical procedures, and patients with neuromuscular disease, weak cough, and abnormal patency of the airway may also benefit from the application of airway clearance techniques. Infants and children up to 3 years of age with airway clearance problems need to be treated with PDPV. Manual percussion with hands alone or a flexible face mask or cup and small mechanical vibrator/percussors, such as the ultrasonic devices, can be used. The intrapulmonary percussive ventilator shows growing promise in this area. The high-frequency oscillator is not supplied with vests of appropriate sizes for tiny babies and has not been studied in this group. Young patients with neuromuscular disease may require assisted ventilation and airway oscillations can be applied. CPAP alone has been shown to improve achievable flow rates that will increase air-liquid interactions for patients with these diseases

  8. 49 CFR 192.325 - Underground clearance.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Underground clearance. 192.325 Section 192.325... Lines and Mains § 192.325 Underground clearance. (a) Each transmission line must be installed with at least 12 inches (305 millimeters) of clearance from any other underground structure not associated...

  9. 30 CFR 18.24 - Electrical clearances.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electrical clearances. 18.24 Section 18.24... APPROVAL OF MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES Construction and Design Requirements § 18.24 Electrical clearances. Minimum clearances between uninsulated electrical...

  10. 14 CFR 25.925 - Propeller clearance.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Propeller clearance. 25.925 Section 25.925 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant General § 25.925 Propeller clearance. Unless smaller clearances are substantiated,...

  11. 19 CFR 122.77 - Clearance certificate.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Clearance certificate. 122.77 Section 122.77 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY AIR COMMERCE REGULATIONS Documents Required for Clearance and Permission To Depart;...

  12. 14 CFR 23.925 - Propeller clearance.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Propeller clearance. 23.925 Section 23.925 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Powerplant General § 23.925 Propeller clearance. Unless...

  13. SKIN KINETICS AND DERMAL CLEARANCE

    Directory of Open Access Journals (Sweden)

    Prakash Shashi

    2012-08-01

    Full Text Available Availability of several therapeutic and cosmetic formulations for topical application has made the research on skin kinetics as a topic of current interest. Topical formulations are typically meant for local effect although there is always a chance that the low molecular weight chemicals are easily transported across the skin layer and make it available in the systemic circulation. Thus there is a major concern about the transport of chemical moieties following the topical application of cosmetics and therapeutic formulations and the real time measurement of the molecules in the skin layer has become obligatory. It is well known that the properties of both drug and the excipients have identical role in determining the skin permeability of chemical moieties. In the last decade several investigations have been carried out in this filed using several in vitro and in vivo models. This review provides a brief account on the basics of skin kinetics, parameters assessed, various techniques and methods adapted in skin kinetic studies. Moreover, we have also discussed about the micro-environment inside the skin layer and the possible mechanism of drug depot formation, skin metabolism and clearance of molecules from the skin layers.

  14. Nucleotide-mediated airway clearance.

    Science.gov (United States)

    Schmid, Andreas; Clunes, Lucy A; Salathe, Mathias; Verdugo, Pedro; Dietl, Paul; Davis, C William; Tarran, Robert

    2011-01-01

    A thin layer of airway surface liquid (ASL) lines the entire surface of the lung and is the first point of contact between the lung and the environment. Surfactants contained within this layer are secreted in the alveolar region and are required to maintain a low surface tension and to prevent alveolar collapse. Mucins are secreted into the ASL throughout the respiratory tract and serve to intercept inhaled pathogens, allergens and toxins. Their removal by mucociliary clearance (MCC) is facilitated by cilia beating and hydration of the ASL by active ion transport. Throughout the lung, secretion, ion transport and cilia beating are under purinergic control. Pulmonary epithelia release ATP into the ASL which acts in an autocrine fashion on P2Y(2) (ATP) receptors. The enzymatic network describes in Chap. 2 then mounts a secondary wave of signaling by surface conversion of ATP into adenosine (ADO), which induces A(2B) (ADO) receptor-mediated responses. This chapter offers a comprehensive description of MCC and the extensive ramifications of the purinergic signaling network on pulmonary surfaces. PMID:21560046

  15. Deposition of aerosols and bronchial clearance measurements

    International Nuclear Information System (INIS)

    A special inhalative device is described for reproducible deposition patterns of radioactive aerosols to measure mucociliary and tussive clearance and to evaluate the effect of drugs on the bronchial tree is described. Additive actions on mucus transport exist between β2-agonists and theophylline, but not incombination with inhalative quarternary ammonium compounds (ipatropium and oxitropium bromide). Mucolytics are generally less effective on mucociliary clearance than β2-agonists and theophylline, positive, negative and nonresponders are ofter seen due to the different viscoelastic properties of the mucus. Mucus transport is more than mucociliary clearance. Two-phase gas/liquid movement and coughing are also important transport mechanisms for bronchial mucus. Therefore, bronchodilators enhance mucus transport by increasing airway patency, which increases total and regional air flow and improves cough clearance. (orig.)

  16. Plasma Creatinine Clearance in the Dog

    Science.gov (United States)

    Frazier, Loy W.

    1977-01-01

    Lists materials and methods for an experiment that demonstrates the concept of glomerular filtration rate (GFR) using anesthesized dogs. In the dog, GFR is equivalent to the renal plasma clearance of exogenous creatinine. (CS)

  17. 48 CFR 801.602-76 - Business clearance review.

    Science.gov (United States)

    2010-10-01

    ... obtain a business clearance review prior to award of any contract, task or delivery order, or blanket... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Business clearance review... Authority, and Responsibilities 801.602-76 Business clearance review. (a) A business clearance review is...

  18. Lower metabolic clearance of tizanidine in Japanese subjects.

    Science.gov (United States)

    Momo, Kenji; Homma, Masato; Kohda, Yukinao

    2013-12-01

    Our aim was to determine whether metabolic clearance, renal clearance, or both elimination pathways contribute to ethnic differences in tizanidine clearance, which is ~ 2-fold higher in Caucasians than in Asians. The pharmacokinetic parameters of tizanidine in 9 healthy male Japanese subjects were compared with those of Caucasians in previous studies. Metabolic clearance of tizanidine was lower in Japanese than in Caucasian subjects (5.9 vs. 8.1 - 10.9 l/h/kg), although renal clearances were similar (0.040 vs. 0.047 - 0.055 l/h/kg). The results suggest that ethnic differences in tizanidine clearance are due to differences in metabolic clearance.

  19. Pharmacologic agents for mucus clearance in bronchiectasis.

    Science.gov (United States)

    Nair, Girish B; Ilowite, Jonathan S

    2012-06-01

    There are no approved pharmacologic agents to enhance mucus clearance in non-cystic fibrosis (CF) bronchiectasis. Evidence supports the use of hyperosmolar agents in CF, and studies with inhaled mannitol and hypertonic saline are ongoing in bronchiectasis. N-acetylcysteine may act more as an antioxidant than a mucolytic in other lung diseases. Dornase α is beneficial to patients with CF, but is not useful in patients with non-CF bronchiectasis. Mucokinetic agents such as β-agonists have the potential to improve mucociliary clearance in normals and many disease states, but have not been adequately studied in patients with bronchiectasis.

  20. Pharmacologic agents for mucus clearance in bronchiectasis.

    Science.gov (United States)

    Nair, Girish B; Ilowite, Jonathan S

    2012-06-01

    There are no approved pharmacologic agents to enhance mucus clearance in non-cystic fibrosis (CF) bronchiectasis. Evidence supports the use of hyperosmolar agents in CF, and studies with inhaled mannitol and hypertonic saline are ongoing in bronchiectasis. N-acetylcysteine may act more as an antioxidant than a mucolytic in other lung diseases. Dornase α is beneficial to patients with CF, but is not useful in patients with non-CF bronchiectasis. Mucokinetic agents such as β-agonists have the potential to improve mucociliary clearance in normals and many disease states, but have not been adequately studied in patients with bronchiectasis. PMID:22640851

  1. Clinical evaluation of amylase-creatinine clearance ratio and amylase isoenzyme clearance in chronic renal failure.

    Science.gov (United States)

    Maeda, M; Otsuki, M; Okano, K; Yamasaki, T; Baba, S

    1981-01-01

    Amylase-creatinine clearance ratio (ACCR) and amylase isoenzyme clearance were determined simultaneously in patients with chronic renal failure. ACCR in patients with compensated renal failure (3.5 +/- 0.4%) was not significantly different from normals (2.6 +/- 0.2%), while that in patients with non-compensated renal failure (6.7 +/- 0.4%) was significantly higher than that in normals. Clearance ratio of pancreatic isoamylase (Amylase-1) relative to creatinine clearance (CAmy . 1/Ccr) in patients with both compensated (5.9 +/- 1.0%) and non-compensated (6.8 +/- 0.4%) renal failure was as high as that in patients with acute pancreatitis (6.6 +/- 0.5%). On the other hand, clearance ratio of salivary isoamylase (Amylase-3) relative to creatinine clearance (CAmy . 3/CCr) in patients with compensated renal failure (1.5 +/- 0.3%) was almost the same as that in normals (2.1 +/- 0.1%), while that in patients with non-compensated renal failure was 5.9 +/- 0.7%, which was significantly higher than that in normals. The present study revealed that elevated ACCR in patients with severely impaired renal function was due to the increase of the clearance ratio for both pancreatic and salivary amylase. These facts suggested that glomerular permeability and tubular reabsorption for pancreatic and salivary amylase might play an important role on ACCR in patients with severely impaired renal function.

  2. Clinical evaluation of amylase-creatinine clearance ratio and amylase isoenzyme clearance in chronic renal failure.

    Science.gov (United States)

    Maeda, M; Otsuki, M; Okano, K; Yamasaki, T; Baba, S

    1981-01-01

    Amylase-creatinine clearance ratio (ACCR) and amylase isoenzyme clearance were determined simultaneously in patients with chronic renal failure. ACCR in patients with compensated renal failure (3.5 +/- 0.4%) was not significantly different from normals (2.6 +/- 0.2%), while that in patients with non-compensated renal failure (6.7 +/- 0.4%) was significantly higher than that in normals. Clearance ratio of pancreatic isoamylase (Amylase-1) relative to creatinine clearance (CAmy . 1/Ccr) in patients with both compensated (5.9 +/- 1.0%) and non-compensated (6.8 +/- 0.4%) renal failure was as high as that in patients with acute pancreatitis (6.6 +/- 0.5%). On the other hand, clearance ratio of salivary isoamylase (Amylase-3) relative to creatinine clearance (CAmy . 3/CCr) in patients with compensated renal failure (1.5 +/- 0.3%) was almost the same as that in normals (2.1 +/- 0.1%), while that in patients with non-compensated renal failure was 5.9 +/- 0.7%, which was significantly higher than that in normals. The present study revealed that elevated ACCR in patients with severely impaired renal function was due to the increase of the clearance ratio for both pancreatic and salivary amylase. These facts suggested that glomerular permeability and tubular reabsorption for pancreatic and salivary amylase might play an important role on ACCR in patients with severely impaired renal function. PMID:6167484

  3. Uptake and clearance of uranium by misgurnus

    International Nuclear Information System (INIS)

    The author studied the bioconcentration and clearance of uranium in misgurnus and determined bioconcentration factors (BCF) as well as uptake and depuration rate constants. The test was performed under semi-static conditions. The depuration of uranium was best described by a two-compartment first order kinetic model

  4. 32 CFR 154.16 - Security clearance.

    Science.gov (United States)

    2010-07-01

    ... requirements for clearance—(1) Top Secret. (i) Final Clearance: (A) BI. (B) Established billet per § 154.13(e... initiated (D) Favorable review of local personnel, base/military police, medical, and other security records...) Provisions of paragraph § 154.14(e) (1) and (2) have been met regarding civilian personnel. (2) Secret....

  5. Dynamics modeling and simulation of mechanism with joint clearance

    Institute of Scientific and Technical Information of China (English)

    BAI Zheng-feng; TIAN Hao; ZHAO Yang

    2010-01-01

    The existence of clearance in the joints of mechanisms system is inevitable.The movements of the real mechanism are deftection from the ideal mechanism due to the clearances and the motion accuracv is decreased.The effects of the hinge clearance on the crank and rocker mechanism system are studied.The svstem dynamics equation with clearance is presented.The contact dynamics model is established using the nonlinear equivalent spring-damp model and the friction effect is considered by using Coulomb friction model.Then the models are incorporated into ADAMS,and based on the model,large numbers numeric simulations are made.The regularity of contact forces in clearance are studied in detail.And the effects of clearance size.clearance friction on the mechanism dynamics characteristic are analyzed.The simulation resuhs Can predict the effects of clearance on the mechanism dynamics characteristic preferably.

  6. 19 CFR 122.26 - Entry and clearance.

    Science.gov (United States)

    2010-04-01

    ... AIR COMMERCE REGULATIONS Private Aircraft § 122.26 Entry and clearance. Private aircraft, as defined... information as set forth in § 122.22(c), and grants electronic clearance via electronic mail or telephone....

  7. Diminished creatinine clearance in anorexia nervosa: reversal with weight gain.

    OpenAIRE

    Boag, F.; Weerakoon, J; Ginsburg, J; Havard, C W; Dandona, P

    1985-01-01

    To assess whether patients with anorexia nervosa have abnormalities in creatinine clearance, we measured plasma creatinine concentration, urinary creatinine excretion, and creatinine clearance in 10 patients with anorexia nervosa before and during treatment. Urinary creatinine excretion and creatinine clearance were diminished in all patients. Nine patients had significant decreases in their plasma creatinine and creatinine clearance was increased even when corrected for body weight and body ...

  8. Wear analysis of revolute joints with clearance in multibody systems

    Science.gov (United States)

    Bai, ZhengFeng; Zhao, Yang; Wang, XingGui

    2013-08-01

    In this work, the prediction of wear for revolute joint with clearance in multibody systems is investigated using a computational methodology. The contact model in clearance joint is established using a new hybrid nonlinear contact force model and the friction effect is considered by using a modified Coulomb friction model. The dynamics model of multibody system with clearance is established using dynamic segmentation modeling method and the computational process for wear analysis of clearance joint in multibody systems is presented. The main computational process for wear analysis of clearance joint includes two steps, which are dynamics analysis and wear analysis. The dynamics simulation of multibody system with revolute clearance joint is carried out and the contact forces are drawn and used to calculate the wear amount of revolute clearance joint based on the Archard's wear model. Finally, a four-bar multibody mechanical system with revolute clearance joint is used as numerical example application to perform the simulation and show the dynamics responses and wear characteristics of multibody systems with revolute clearance joint. The main results of this work indicate that the contact between the joint elements is wider and more frequent in some specific regions and the wear phenomenon is not regular around the joint surface, which causes the clearance size increase non-regularly after clearance joint wear. This work presents an effective method to predict wear of revolute joint with clearance in multibody systems.

  9. 10 CFR 706.31 - Clearance of conciliators and arbitrators.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Clearance of conciliators and arbitrators. 706.31 Section... RELATIONS Contract Negotiation and Administration § 706.31 Clearance of conciliators and arbitrators. Conciliators and arbitrators who are regularly assigned to DOE cases may be processed for “Q” clearance at...

  10. Guangzhou Customs Guide to Clearance of Import/Export Goods

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    @@ Management of the Enterprises Granted for Convenient and Quick Customs Clearance 1.What is the enterprise granted for convenient and quick customs clearance? Customs General Administration and the Ministry of Foreign Trade and Economic Cooperation jointly issued policy measures to facilitate customs clearance in 2001 to further support the development of hightech industries.The enterprise .

  11. 14 CFR 1260.63 - Customs clearance and visas.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Customs clearance and visas. 1260.63 Section 1260.63 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION GRANTS AND COOPERATIVE AGREEMENTS General Special Conditions § 1260.63 Customs clearance and visas. Customs Clearance and Visas...

  12. 14 CFR 27.661 - Rotor blade clearance.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Rotor blade clearance. 27.661 Section 27... AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Rotors § 27.661 Rotor blade clearance. There must be enough clearance between the rotor blades and other parts of the structure...

  13. 14 CFR 29.661 - Rotor blade clearance.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Rotor blade clearance. 29.661 Section 29... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Rotors § 29.661 Rotor blade clearance. There must be enough clearance between the rotor blades and other parts of the structure...

  14. 32 CFR 644.517 - Clearance of Army lands.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Clearance of Army lands. 644.517 Section 644.517 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL PROPERTY REAL... and Improvements § 644.517 Clearance of Army lands. The responsibility for performing clearance...

  15. Glial K(+) Clearance and Cell Swelling

    DEFF Research Database (Denmark)

    Macaulay, Nanna; Zeuthen, Thomas

    2012-01-01

    An important feature of neuronal signalling is the increased concentration of K(+) in the extracellular space. The K(+) concentration is restored to its original basal level primarily by uptake into nearby glial cells. The molecular mechanisms by which K(+) is transferred from the extracellular...... space into the glial cell are debated. Although spatial buffer currents may occur, their quantitative contribution to K(+) clearance is uncertain. The concept of spatial buffering of K(+) precludes intracellular K(+) accumulation and is therefore (i) difficult to reconcile with the K(+) accumulation...... repeatedly observed in glial cells during K(+) clearance and (ii) incompatible with K(+)-dependent glial cell swelling. K(+) uptake into non-voltage clamped cultured glial cells is carried out by the Na(+)/K(+)-ATPase and the Na(+)/K(+)/Cl(-) cotransporter in combination. In brain slices and intact optic...

  16. ADSORBENTS USED IN THE CLEARANCE OF ENDOTOXIN

    Institute of Scientific and Technical Information of China (English)

    YU Mei; LIU Tao; Hou Guanghui; YUAN Zhi

    2003-01-01

    A series of modified poly (methyl methacrylate, PMMA) resins were prepared and compared their adsorption abilities to endotoxin. The results showed that adsorbents, which were grafted with tertiary amine and long spacing arms, had the best adsorption capacities and good blood compatibility, It is hopeful to be used as adsorbent in hemoperfusion for clinical clearance of endotoxin. The influence of original concentration of endotoxin on adsorption and the adsorption mechanism were also investigated.

  17. Airway Clearance Devices for Cystic Fibrosis

    Science.gov (United States)

    2009-01-01

    Executive Summary Objective The purpose of this evidence-based analysis is to examine the safety and efficacy of airway clearance devices (ACDs) for cystic fibrosis and attempt to differentiate between devices, where possible, on grounds of clinical efficacy, quality of life, safety and/or patient preference. Background Cystic fibrosis (CF) is a common, inherited, life-limiting disease that affects multiple systems of the human body. Respiratory dysfunction is the primary complication and leading cause of death due to CF. CF causes abnormal mucus secretion in the airways, leading to airway obstruction and mucus plugging, which in turn can lead to bacterial infection and further mucous production. Over time, this almost cyclical process contributes to severe airway damage and loss of respiratory function. Removal of airway secretions, termed airway clearance, is thus an integral component of the management of CF. A variety of methods are available for airway clearance, some requiring mechanical devices, others physical manipulation of the body (e.g. physiotherapy). Conventional chest physiotherapy (CCPT), through the assistance of a caregiver, is the current standard of care for achieving airway clearance, particularly in young patients up to the ages of six or seven. CF patients are, however, living much longer now than in decades past. The median age of survival in Canada has risen to 37.0 years for the period of 1998-2002 (5-year window), up from 22.8 years for the 5-year window ending in 1977. The prevalence has also risen accordingly, last recorded as 3,453 in Canada in 2002, up from 1,630 in 1977. With individuals living longer, there is a greater need for independent methods of airway clearance. Airway Clearance Devices There are at least three classes of airway clearance devices: positive expiratory pressure devices (PEP), airway oscillating devices (AOD; either handheld or stationary) and high frequency chest compression (HFCC)/mechanical percussion (MP

  18. [Ratio of amylase clearance and creatinine clearance in the diagnosis of acute pancreatitis].

    Science.gov (United States)

    Haffter, D; Reichlin, B; Gyr, K

    1981-05-30

    In 21 healthy volunteers the ratio of amylase clearance and creatinine clearance (Cam/Ccr) was determined in urine collected at admission, after a 1-hour collection period and after a 2-hour collection period. The normal values were 1.8 +/- 1.6%, 1.9 +/- 2% and 2.0 +/- 1.7% respectively. They were comparable with those published by others. The reproducibility of the method was acceptable (r = 0.62). When compared with serum amylase determinations, Cam/Ccr showed neither better sensitivity in 19 patients suffering an acute episode of proven pancreatitis, nor better specificity in 19 patients with acute abdomen but no evidence of pancreatitis.

  19. Clearance and release from control - An international perspective

    International Nuclear Information System (INIS)

    This paper tries to give an overview of the clearance, or release from regulatory control, on an international scale, including some of those countries where clearance has become or is about to become vital for D and D. The emphasis lies on the impact of clearance, and in particular of differences between clearance levels of various countries, on D and D. Relevance of clearance for D and D of nuclear installations Clearance is an essential part of waste management (or more general, material management) in nuclear installations, and in particular during the decommissioning phase where waste streams continues to arise. Of course, the relevance of clearance in a particular country depends on a number of factors, like: availability of a final repository and its price; prevailing decommissioning strategy; number of nuclear installations reaching decommissioning phase. This small selection of reasons why clearance may be of varying importance for different countries may already suffice to illustrate why up to now clearance has been developed and implemented in quite different ways. If one thinks of additional reasons that may influence clearance, like politics, the public opinion, availability of funds etc., the situation becomes even more complex. It is, however safe to draw the conclusion that countries with a certain number of nuclear installations which have been or will soon be shut down or which are already in the decommissioning phase will need to implement provisions for clearance. This has indeed been the case with countries like the UK, Germany, the USA, Sweden, and a number of others. It is not essential for clearance levels to be exactly equal between various countries. They may differ as long as the difference is not too large, e.g. the values fall into the same order of magnitude. This is the reason why for example Germany has no problems with clearance levels which differ from the EU recommendation RP 122 partially adopted in a number of EU countries

  20. Amylase creatinine clearance ratio after biliary surgery.

    Science.gov (United States)

    Donaldson, L A; McIntosh, W; Joffe, S N

    1977-01-01

    The amylase creatinine clearance ratio (ACCR) is considered to be a more sensitive index of acute pancreatitis than the serum amylase level. Serial ACCR estimations were undertaken in 25 patients undergoing an elective cholecystectomy. Using accepted criteria, 28% of these patients developed, in the postoperative period, biochemical evidence of pancreatic gland damage, although the serum amylase level remained normal. This raised ACCR was particularly noted in patients who had undergone an exploration of the common bile duct. The ACCR would appear to be a more sensitive index of pancreatic gland disruption secondary to biliary surgery than the serum amylase level.

  1. Amylase creatinine clearance ratio after biliary surgery.

    Science.gov (United States)

    Donaldson, L A; McIntosh, W; Joffe, S N

    1977-01-01

    The amylase creatinine clearance ratio (ACCR) is considered to be a more sensitive index of acute pancreatitis than the serum amylase level. Serial ACCR estimations were undertaken in 25 patients undergoing an elective cholecystectomy. Using accepted criteria, 28% of these patients developed, in the postoperative period, biochemical evidence of pancreatic gland damage, although the serum amylase level remained normal. This raised ACCR was particularly noted in patients who had undergone an exploration of the common bile duct. The ACCR would appear to be a more sensitive index of pancreatic gland disruption secondary to biliary surgery than the serum amylase level. PMID:402305

  2. Study of blade clearance effects on centrifugal pumps

    Science.gov (United States)

    Hoshide, R. K.; Nielson, C. E.

    1972-01-01

    A program of analysis, design, fabrication, and testing has been conducted to develop and experimentally verify analytical models to predict the effects of impeller blade clearance on centrifugal pumps. The effect of tip clearance on pump efficiency, and the relationship between the head coefficient and torque loss with tip clearance was established. Analysis were performed to determine the cost variation in design, manufacture, and test that would occur between unshrouded and shrouded impellers. An impeller, representative of typical rocket engine impellers, was modified by removing its front shroud to permit variation of its blade clearances. It was tested in water with special instrumentation to provide measurements of blade surface pressures during operation. Pump performance data were obtained from tests at various impeller tip clearances. Blade pressure data were obtained at the nominal tip clearance. Comparisons of predicted and measured data are given.

  3. Allometric scaling for predicting human clearance of bisphenol A

    Energy Technology Data Exchange (ETDEWEB)

    Collet, Séverine H., E-mail: s.collet@envt.fr; Picard-Hagen, Nicole, E-mail: n.hagen-picard@envt.fr; Lacroix, Marlène Z., E-mail: m.lacroix@envt.fr; Puel, Sylvie, E-mail: s.puel@envt.fr; Viguié, Catherine, E-mail: c.viguie@envt.fr; Bousquet-Melou, Alain, E-mail: a.bousquet-Melou@envt.fr; Toutain, Pierre-Louis, E-mail: pltoutain@wanadoo.fr; Gayrard, Véronique, E-mail: v.gayrard@envt.fr

    2015-05-01

    The investigation of interspecies differences in bisphenol A (BPA) pharmacokinetics (PK) may be useful for translating findings from animal studies to humans, identifying major processes involved in BPA clearance mechanisms, and predicting BPA PK parameters in man. For the first time, a large range of species in terms of body weight, from 0.02 kg (mice) to 495 kg (horses) was used to predict BPA clearance in man by an allometric approach. BPA PK was evaluated after intravenous administration of BPA in horses, sheep, pigs, dogs, rats and mice. A non-compartmental analysis was used to estimate plasma clearance and steady state volume of distribution and predict BPA PK parameters in humans from allometric scaling. In all the species investigated, BPA plasma clearance was high and of the same order of magnitude as their respective hepatic blood flow. By an allometric scaling, the human clearance was estimated to be 1.79 L/min (equivalent to 25.6 mL/kg.min) with a 95% prediction interval of 0.36 to 8.83 L/min. Our results support the hypothesis that there are highly efficient and hepatic mechanisms of BPA clearance in man. - Highlights: • Allometric scaling was used to predict BPA pharmacokinetic parameters in humans. • In all species, BPA plasma clearance approached hepatic blood flow. • Human BPA clearance was estimated to be 1.79 L/min.

  4. Clearance systems in the brain-implications for Alzheimer disease.

    Science.gov (United States)

    Tarasoff-Conway, Jenna M; Carare, Roxana O; Osorio, Ricardo S; Glodzik, Lidia; Butler, Tracy; Fieremans, Els; Axel, Leon; Rusinek, Henry; Nicholson, Charles; Zlokovic, Berislav V; Frangione, Blas; Blennow, Kaj; Ménard, Joël; Zetterberg, Henrik; Wisniewski, Thomas; de Leon, Mony J

    2015-08-01

    Accumulation of toxic protein aggregates-amyloid-β (Aβ) plaques and hyperphosphorylated tau tangles-is the pathological hallmark of Alzheimer disease (AD). Aβ accumulation has been hypothesized to result from an imbalance between Aβ production and clearance; indeed, Aβ clearance seems to be impaired in both early and late forms of AD. To develop efficient strategies to slow down or halt AD, it is critical to understand how Aβ is cleared from the brain. Extracellular Aβ deposits can be removed from the brain by various clearance systems, most importantly, transport across the blood-brain barrier. Findings from the past few years suggest that astroglial-mediated interstitial fluid (ISF) bulk flow, known as the glymphatic system, might contribute to a larger portion of extracellular Aβ (eAβ) clearance than previously thought. The meningeal lymphatic vessels, discovered in 2015, might provide another clearance route. Because these clearance systems act together to drive eAβ from the brain, any alteration to their function could contribute to AD. An understanding of Aβ clearance might provide strategies to reduce excess Aβ deposits and delay, or even prevent, disease onset. In this Review, we describe the clearance systems of the brain as they relate to proteins implicated in AD pathology, with the main focus on Aβ. PMID:26195256

  5. Do dialysate conductivity measurements provide conductivity clearance or ionic dialysance?

    Science.gov (United States)

    Petitclerc, T

    2006-11-01

    Dialysate conductivity measurements allow on-line estimation of urea clearance during hemodialysis session. Conductivity measurements provide a value of 'conductivity clearance' for some authors, but a value of 'ionic dialysance' for others. This paper aims at explaining which term should be the more appropriate. Clearance is a parameter defined for measuring the power of a mechanism, which aims at 'clearing' a solution by depurating some solutes. In hemodialysis, clearance measures the efficacy of patient's depuration. In contrast, dialysance measures the capability of transferring solutes between blood and dialysate. The conventional definition of dialysance, requiring the absence of convective transfer, should be generalized to the case of the usual presence of ultrafiltration during the hemodialysis session. For a solute (as urea) absent from the dialysate delivered to the dialyzer inlet, the clearance is equal to its dialysance. In order to avoid a dramatic fall in ionic concentrations during hemodialysis treatment, the clearance of ions is reduced by adding these ions in the dialysate and becomes lower than their dialysance. Conductivity measurements provide a value of electrolytes dialysance. Thus the term of 'ionic dialysance' is more appropriate than the term of 'conductivity clearance'. Nevertheless ionic dialysance represents a good estimation of urea clearance.

  6. Radioaerosol delivery and clearance in patients with respiratory failure

    International Nuclear Information System (INIS)

    A technique for radioaerosol delivery to patients requiring mechanical ventilation is described. Ventilation images and pulmonary radioaerosol clearance rates were successfully obtained in 35 patients regardless of ventilator type or level of positive end-expiratory pressure (PEEP). Those patients with noncardiogenic pulmonary edema (NPE) had significantly increased clearance rates relative to those patients in whom NPE was not present

  7. 48 CFR 32.502-2 - Contract finance office clearance.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Contract finance office clearance. 32.502-2 Section 32.502-2 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION... finance office clearance. The contracting officer shall obtain the approval of the contract finance...

  8. 48 CFR 1432.502-2 - Contract finance office clearance.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Contract finance office clearance. 1432.502-2 Section 1432.502-2 Federal Acquisition Regulations System DEPARTMENT OF THE INTERIOR... finance office clearance. The CO shall obtain approval of the bureau finance office prior to...

  9. 48 CFR 832.502-2 - Contract finance office clearance.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Contract finance office clearance. 832.502-2 Section 832.502-2 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS... finance office clearance. Contracting officers must obtain approval from the DSPE before taking...

  10. 32 CFR 644.522 - Clearance of military scrap.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Clearance of military scrap. 644.522 Section 644... Excess Land and Improvements § 644.522 Clearance of military scrap. Military scrap can contain or be... determining whether scrap metal will be removed should be the safety of persons coming on the land in...

  11. 14 CFR 29.411 - Ground clearance: tail rotor guard.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Ground clearance: tail rotor guard. 29.411... System Loads § 29.411 Ground clearance: tail rotor guard. (a) It must be impossible for the tail rotor to contact the landing surface during a normal landing. (b) If a tail rotor guard is required to...

  12. 14 CFR 27.411 - Ground clearance: tail rotor guard.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Ground clearance: tail rotor guard. 27.411... System Loads § 27.411 Ground clearance: tail rotor guard. (a) It must be impossible for the tail rotor to contact the landing surface during a normal landing. (b) If a tail rotor guard is required to...

  13. Benefits of Improved HP Turbine Active Clearance Control

    Science.gov (United States)

    Ruiz, Rafael; Albers, Bob; Sak, Wojciech; Seitzer, Ken; Steinetz, Bruce M.

    2007-01-01

    As part of the NASA Propulsion 21 program, GE Aircraft Engines was contracted to develop an improved high pressure turbine(HPT) active clearance control (ACC) system. The system is envisioned to minimize blade tip clearances to improve HPT efficiency throughout the engine operation range simultaneously reducing fuel consumption and emissions.

  14. Allometric scaling for predicting human clearance of bisphenol A

    International Nuclear Information System (INIS)

    The investigation of interspecies differences in bisphenol A (BPA) pharmacokinetics (PK) may be useful for translating findings from animal studies to humans, identifying major processes involved in BPA clearance mechanisms, and predicting BPA PK parameters in man. For the first time, a large range of species in terms of body weight, from 0.02 kg (mice) to 495 kg (horses) was used to predict BPA clearance in man by an allometric approach. BPA PK was evaluated after intravenous administration of BPA in horses, sheep, pigs, dogs, rats and mice. A non-compartmental analysis was used to estimate plasma clearance and steady state volume of distribution and predict BPA PK parameters in humans from allometric scaling. In all the species investigated, BPA plasma clearance was high and of the same order of magnitude as their respective hepatic blood flow. By an allometric scaling, the human clearance was estimated to be 1.79 L/min (equivalent to 25.6 mL/kg.min) with a 95% prediction interval of 0.36 to 8.83 L/min. Our results support the hypothesis that there are highly efficient and hepatic mechanisms of BPA clearance in man. - Highlights: • Allometric scaling was used to predict BPA pharmacokinetic parameters in humans. • In all species, BPA plasma clearance approached hepatic blood flow. • Human BPA clearance was estimated to be 1.79 L/min

  15. Study of global operational needs for mine clearance equipment

    Science.gov (United States)

    Blagden, Paddy M.

    2003-09-01

    The Geneva International Centre for Humanitarian Demining studied the needs of landmine clearance groups for equipment to carry out specific functions of mine clearance. This was done on a global level, and useful results were obtained, which will provide the basis for further analysis.

  16. Predicting clearance in humans from in vitro data.

    Science.gov (United States)

    Obach, R Scott

    2011-01-01

    The use of in vitro metabolism in scaling to predict human clearance of new chemical entities has become a commonplace activity in the research and development of new drugs. The measurement of in vitro lability in human liver microsomes, a rich source of drug metabolizing cytochrome P450 enzymes, has become a high throughput screen in many research organizations which is a testament to its usefulness in drug design. In this chapter, the methods used to scale in vitro clearance data to predict in vivo clearance are described. Importantly, the numerous assumptions that are required in order to use in vitro data in this manner are laid out. These include assumptions regarding the scaling process as well as technical aspects of the generation of the in vitro data. Finally, some other drug clearance processes that have been emerging as important are described with regard to ongoing research efforts to develop clearance prediction methods.

  17. Analysis of conservativity analysis for clearance levels. Final report

    International Nuclear Information System (INIS)

    When deriving clearance levels for material from nuclear installations it is necessary to proceed with a certain degree of conservativity. This can, however, differ between various sets of clearance levels leading to inconsistencies between clearance pathways. The aim of the work therefore is to compare levels of conservativity for the following two sets of clearance levels: clearance levels for disposal as conventional waste and for metallic materials for recycling/reuse. A method was developed to quantify the degree of conservativity and make it comparable. The actual and future situation for disposal of (conventional) wastes in Germany was analysed. In addition, the masses, nuclide vectors, geographical distribution etc. for slightly radioactive material being cleared for conventional disposal was analysed and modelled and the resulting dose distributions were calculated. The values for the clearance levels were taken from the 1995 recommendation by the German Commission on Radiation Protection (SSK). By using realistic scenarios, the exposure was calculated for the personnel on the landfills and for persons of the general public being exposed via groundwater pathways. It could be shown that the trivial dose range will not be exceeded even if the masses of cleared material per landfill site exceed 100 Mg/a. Because of the types and distribution of nuclear installations in Germany and because of the nuclide vectors it is therefore not necessary to limit the masses per landfill sites. Clearance levels that are determined by the exposure pathways external exposure to and the inhalation of dust by the landfill personnel show a similar level of conservativity as those for metal scrap. This means that the clearance levels for gamma emitting nuclides are not overly restrictive. Although radiologically justified, raising the clearance levels would not lead to an increase of the material quantities because other nuclides of the respective nuclide vectors are limiting. In

  18. Nuclear regulation. NRC's security clearance program can be strengthened

    International Nuclear Information System (INIS)

    Because of the national security implications of its programs, the Nuclear Regulatory Commission (NRC) investigates the background of its employees and consultants as well as others to ensure that they are reliable and trustworthy. If the investigation indicates that an employee will not endanger national security, NRC grants a security clearance that allows access to classified information, material, and facilities. NRC also requires periodic checks for some clearance holders to ensure their continued clearance eligibility. The Chairman, Subcommittee on Environment, Energy, and Natural Resources, House Committee on Government Operations, asked GAO to review NRC's personnel security clearance program and assess the procedures that NRC uses to ensure that those who operate nuclear power plants do not pose a threat to the public. The Atomic Energy Act of 1954 requires NRC to conduct background investigations of its employees and consultants as well as others who have access to classified information, material, or facilities. To do this, NRC established a personnel security clearance program. Under NRC policies, a security clearance is granted after the Office of Personnel Management (OPM) or the Federal Bureau of Investigation checks the background of those applying for an NRC clearance. NRC also periodically reassesses the integrity of those holding the highest level clearance. NRC employees, consultants, contractors, and licensees as well as other federal employees hold approximately 10,600 NRC clearances. NRC does not grant clearances to commercial nuclear utility employees unless they require access to classified information or special nuclear material. However, the utilities have voluntarily established screening programs to ensure that their employees do not pose a threat to nuclear plants. NRC faces a dilemma when it hires new employees. Although its policy calls for new hires to be cleared before they start work, the security clearance process takes so long

  19. Effects of drugs on mucus clearance.

    Science.gov (United States)

    Houtmeyers, E; Gosselink, R; Gayan-Ramirez, G; Decramer, M

    1999-08-01

    Mucociliary clearance (MCC), the process in which airway mucus together with substances trapped within are moved out of the lungs, is an important defence mechanism of the human body. Drugs may alter this process, such that it is necessary to know the effect of the drugs on MCC. Indeed, agents stimulating MCC may be used therapeutically in respiratory medicine, especially in patients suspected of having an impairment of their mucociliary transport system. In contrast, caution should be taken with drugs depressing MCC as an undesired side-effect, independently of their therapeutic indication. Since cough clearance (CC) serves as a back-up system when MCC fails, the influence of drugs must be examined not only on MCC but also on CC. Ultimately, the clinical repercussions of alterations in mucus transport induced by drug administration must be studied. Tertiary ammonium compounds (anticholinergics), aspirin, anaesthetic agents and benzodiazepines have been shown to be capable of depressing the mucociliary transport system. Cholinergics, methylxanthines, sodium cromoglycate, hypertonic saline, saline as well as water aerosol have been shown to increase MCC. Adrenergic antagonists, guaifenesin, S-carboxymethylcysteine, sodium 2-mercapto-ethane sulphonate and frusemide have been reported not to alter the mucociliary transport significantly. Amiloride, uridine 5'-triphosphate (UTP), quaternary ammonium compounds (anticholinergics), adrenergic agonists, corticosteroids, recombinant human deoxyribonuclease (rhDNase), N-acetylcysteine, bromhexine and ambroxol have been reported either not to change or to augment MCC. Indirect data suggest that surfactant as well as antibiotics may improve the mucociliary transport system. As for the influence of drugs on CC, amiloride and rhDNase have been demonstrated to increase the effectiveness of cough. A trend towards an improved CC was noted after treatment with adrenergic agonists. The anticholinergic agent ipratropium bromide, which

  20. Analysis of viral clearance unit operations for monoclonal antibodies.

    Science.gov (United States)

    Miesegaes, George; Lute, Scott; Brorson, Kurt

    2010-06-01

    Demonstration of viral clearance is a critical step in assuring the safety of biotechnology products. We generated a viral clearance database that contains product information, unit operation process parameters, and viral clearance data from monoclonal antibody and antibody-related regulatory submissions to FDA. Here we present a broad overview of the database and resulting analyses. We report that the diversity of model viruses tested expands as products transition to late-phase. We also present averages and ranges of viral clearance results by Protein A and ion exchange chromatography steps, low pH chemical inactivation, and virus filtration, focusing on retro- and parvoviruses. For most unit operations, an average log reduction value (LRV, a measure of clearance power) for retrovirus of >4 log(10) were measured. Cases where clearance data fell outside of the anticipated range (i.e., outliers) were rationally explained. Lastly, a historical analysis did not find evidence of any improvement trend in viral clearance over time. The data collectively suggest that many unit operations in general can reliably clear viruses.

  1. Integrated Turbine Tip Clearance and Gas Turbine Engine Simulation

    Science.gov (United States)

    Chapman, Jeffryes W.; Kratz, Jonathan; Guo, Ten-Huei; Litt, Jonathan

    2016-01-01

    Gas turbine compressor and turbine blade tip clearance (i.e., the radial distance between the blade tip of an axial compressor or turbine and the containment structure) is a major contributing factor to gas path sealing, and can significantly affect engine efficiency and operational temperature. This paper details the creation of a generic but realistic high pressure turbine tip clearance model that may be used to facilitate active tip clearance control system research. This model uses a first principles approach to approximate thermal and mechanical deformations of the turbine system, taking into account the rotor, shroud, and blade tip components. Validation of the tip clearance model shows that the results are realistic and reflect values found in literature. In addition, this model has been integrated with a gas turbine engine simulation, creating a platform to explore engine performance as tip clearance is adjusted. Results from the integrated model explore the effects of tip clearance on engine operation and highlight advantages of tip clearance management.

  2. NUMERICAL SIMULATION OF TIP-CLEARANCE FLOW IN CASCADE

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The tip-clearance flow in a cascade was numerically simulated by solving the RANS equations of incompressible fluids. The computational model was based upon the artificial compressibility formulation proposed by Chorin. The Baldwin-Lomax turbulence model was used to make the governing equations closed. For the specific structure of tip-clearance flow, a multi-block grid structure was adopted to facilitate numerical computations. The comparison of numerical results with experimental data indicates that the present method is capable of simulating tip-clearance flows with satisfactory accuracy.

  3. Clearance from the anterior chamber of RBCs from human diabetics

    International Nuclear Information System (INIS)

    Erythrocytes from diabetic patients manifest decreased deformability and increased adherence. These abnormal membrane properties may diminish the ability of erythrocytes (RBCs) from diabetics to undergo deformation in passage through the trabecular meshwork. Using sodium chromate Cr 51-labeled RBCs from type I diabetic patients with proliferative retinopathy and normal control subjects, we studied RBC clearance from the rabbit anterior chamber. The mean time for 50% clearance (T50) of RBCs from diabetics (76 hours) was significantly longer than that for RBCs from normal subjects (19.5 hours). In this model, RBCs from diabetics have a slower clearance from the anterior chamber than do RBCs from normal subjects

  4. The compliance contact model of cylindrical joints with clearances

    Institute of Scientific and Technical Information of China (English)

    Caishan Liu; Ke Zhang; Lei Yang; Keren Wang

    2005-01-01

    This paper is concerned with the determination of the normal force-displacement (NFD) relation for the contact problem of cylindrical joints with clearance. A simple formulation for this contact problem is developed by modeling the pin as a rigid wedge and the elastic plate as a simple Winkler elastic foundation. The numerical results show that the normal displacement relation based on Hertz theory is only valid for the case of large clearance with a small normal load, and the NFD relation based on Persson theory is only effective in the case of very small clearance. The proposed approximate model in this paper gives better results than Hertz theory and Persson theory in a large range of clearances as seen from the comparison with the results of FEM.

  5. Design Optimization of Ground Clearance of Domestic Cars

    Directory of Open Access Journals (Sweden)

    Debojyoti Mitra

    2010-07-01

    Full Text Available Drag and lift forces plays a vital role in the performance and stability of vehicles. Less drag means less fuel consumption and hence less vehicular pollution. Also, lower lift force means higher chance of adhesion of the car body with the ground causing less overturning of the vehicle, which improves the vehicle performance. Both drag and lift forces can be manipulated by varying the ground clearance of the cars. The present study concentrates on studying the effect of ground clearance on these aerodynamic forces experimentally. Wind tunnel studies with a notch-back car model revealed increase in drag and decrease in lift with increase in ground clearance. Therefore, optimization is required for designing the best ground clearance and a preferable value of the same is thus obtained.

  6. 49 CFR 229.71 - Clearance above top of rail.

    Science.gov (United States)

    2010-10-01

    ..., DEPARTMENT OF TRANSPORTATION RAILROAD LOCOMOTIVE SAFETY STANDARDS Safety Requirements Suspension System § 229.71 Clearance above top of rail. No part or appliance of a locomotive except the wheels,...

  7. Enhancement of the amylase-creatinine clearance ratio in pregnancy.

    Science.gov (United States)

    Naeije, R; Neuray, F; Van Melsen, A; Delcourt, A

    1979-01-01

    The renal clearance of amylase, expressed as a proportion of simultaneous creatinine clearance (Cam/-Ccr), was determined in 131 women in various stages of pregnancy. No abnormal serum levels of amylase were found. A moderate but significant increase in Cam/Ccr occurred during the last 15 weeks of pregnancy. Possible causes for this change were investigated in smaller groups of subjects. No increase in rapidly cleared isoamylase could be detected. No modification in renal tubular handling of protein could be evidenced, as assessed by measurements of the renal clearance of beta 2 microglobulin, expressed as a proportion of simultaneous creatinine clearance. An incrased glomerular permeability to amylase probably accounts for elevated Cam/Ccr in pregnancy.

  8. IFNL4 affects clearance of hepatitis C virus

    Science.gov (United States)

    Scientists have discovered a new human interferon gene, Interferon Lambda 4 (IFNL4), that affects clearance of the hepatitis C virus. They also identified an inherited genetic variant within IFNL4 that predicts how people respond to treatment for hepatit

  9. The optimal clearance design of micro-punching die

    Directory of Open Access Journals (Sweden)

    K.S. Lee

    2008-07-01

    Full Text Available Purpose: The purpose of this research paper is focused on the optimal clearance design of micro-punching die by abductive network and SA method.Design/methodology/approach: The punching data (input and wear size (output were collected for a training database. In order to select proper clearance to evaluate the wear of die, the abductive network was used to establish an efficient relationship between input parameters and output result. This can help to predict wear size under any degree of clearance and hence to replace worn punches and dies at the right time. A simulated annealing (SA optimization algorithm with a performance index is then applied to the neural network for searching the optimal clearance parameters, and obtains rather satisfactory result as compared with the corresponding experiment verification.Findings: This study aims to identify the relationship between clearance and service life of micro punches using the Neural Network, and to find relational data involving the service life of punches and punching parameters in non-metal blanking processes. The result can be used to estimate optimal clearance between punch and die for industrial applications.Research limitations/implications: In this study, the practical punching processes with different punching conditions were carried out for a set of training data. A trained model exhibited a relationship between service life and clearance of micro punch and die through an abductive network system. The predicted value of wear by abductive network is very close to the actual experimental value, with an error of less than 8%. This result satisfies the required standard for IC factory production.Originality/value: A good clearance design not only increases the quality of product manufactured, but also reduces product’s burr. As a result, the wear of punches and dies can be greatly reduced and the life expectancy of punching dies increased.

  10. Fluid damping clearance in a control valve of injector

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jianming; ZHANG Weigang; YANG Bing; WANG Yawei

    2007-01-01

    A force model of a control valve of injector is set up, and the changes of the fluid damping clearance are investigated on the basis of the results of the computational fluid dynamics (CFD) and the experiments of control valve of injector. Results indicate that a damping clearance of 0.02-0.03 mm between the poppet and the valve guide is the most sufficient to dampen any excessive control valve poppet bouncing.

  11. Experimental study on fluid flow in arciform clearance

    Institute of Scientific and Technical Information of China (English)

    邵俊鹏; 汤卉; 贾慧娟

    2002-01-01

    The system damping and dynamic characteristics can be further improved by properly increasing thedamping coefficient ξh. For a special hydraulic damping structure, an arciform damping clearance often used inFCS, a mathematical model has been established for fluid flow using the theory of laminar flow in the clearanceof parallel plates. Analytical calculations are made for fluid flow in the arciform clearance and relational expres-sion is deduced for flow rate along the arciform cleaance height, pressure difference, maximum arciform clear-ance height, the flow rate for the fluid flow in arciform clearance as well, and its simplified formula is obtainedby using the theory of hydrodynamics and the curve - fitting method. This paper consists of two sections: the firstsection focuses on the theoretical analysis by using the simplified mathematical model and the second sectionmainly describes experimental analysis. The simplified formula is corrected with experimental results by consid-erig various boundary conditions of the damping clearance. Experimental results show that this study of arciformdamping clearance is reliable and practical.

  12. Model of mucociliary clearance in cystic fibrosis lungs.

    Science.gov (United States)

    Kurbatova, P; Bessonov, N; Volpert, V; Tiddens, H A W M; Cornu, C; Nony, P; Caudri, D

    2015-05-01

    Mucus clearance is a primary innate defense mechanism in the human airways. Cystic fibrosis (CF) is a genetic disease caused by mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR) protein. CF is characterized by dehydration of airway surface liquid and impaired mucociliary clearance. As a result, microorganisms are not efficiently removed from the airways, and patients experience chronic pulmonary infections and inflammation. We propose a new physiologically based mathematical model of muco-ciliary transport consisting of the two major components of the mucociliary clearance system: (i) periciliary liquid layer (PCL) and (ii) mucus layer. We study mucus clearance under normal conditions and in CF patients. Restoring impaired clearance of airway secretions in one of the major goals of therapy in patients with CF. We consider the action of the aerosolized and inhaled medication dornase alfa, which reduces the viscosity of cystic fibrosis mucus, by selectively cleaving the long DNA strands it contains. The results of the model simulations stress the potential relevance of the location of the drug deposition in the central or peripheral airways. Mucus clearance was increased in case the drug was primarily deposited peripherally, i.e. in the small airways. PMID:25746843

  13. Radioactive Aerosols in the Clinical Study of Pulmonary Clearance

    International Nuclear Information System (INIS)

    The study of pulmonary clearance mechanisms has acquired particular importance owing to the growing pollution of the environment and to the increasing incidence and seriousness of cases of pneumoconiosis. Such research is particularly important in radiopathology because of the frequent occurrence of respiratory radioactive contamination. The authors' aim is to tackle this problem and in particular to study long-term clearance mechanisms. Before starting this work, however, they propose to determine the contamination parameters as accurately as possible. For this purpose they plan to study respiratory function in normal subjects by administering labelled aerosols with well-defined physico-chemical characteristics; the first stage of the investigation is then to observe the kinetics of fixation and clearance in the short term. They describe the installations used for this voluntary contamination which must provide a means of producing the aerosols and administering them in controlled amounts and must also ensure efficient protection of the operators against irradiation arid contamination. The choice of the aerosols is also discussed: this is governed mainly by the nature of the vectors, the particle size and the physical characteristics of the tracers. Finally, the authors outline the detection and measuring techniques which they are using to study contamination kinetics, evaluate contamination burdens and follow the short-term clearance. These data constitute a preliminary basis for the study of long-term clearance. (author)

  14. Progress with volunteer studies of nasal deposition and clearance

    International Nuclear Information System (INIS)

    Inhalation is the main route of intake of radioactive material for workers, and can be an important pathway for members of the public following accidental releases of radioactivity to the environment. Much of the inhaled radioactivity initially deposits in the nose, typically over 40% for particles of aerodynamic diameter (dae) greater than 2 μm. However, there is remarkably little information on the clearance from the human nose of particles deposited during inhalation and, until now, none on the clearance of the significant fraction of material that remains in the nasal passage for more than 12 hours. NRPB is conducting a volunteer study to determine the effects of particle size and breathing pattern on particle deposition in, and clearance from, the human nasal passage. This article summarises results obtained to date. (author)

  15. Improving mucociliary clearance in chronic obstructive pulmonary disease.

    Science.gov (United States)

    Bhowmik, Angshu; Chahal, Kamaljeet; Austin, Gillian; Chakravorty, Indranil

    2009-04-01

    Patients with COPD usually experience mucus hypersecretion as a result of airway inflammation and response to noxious stimuli. These in turn lead to worsening airway resistance, impaired airflow, increased work of breathing, dyspnoea and exercise intolerance. Mucus hypersecretion may also lead to increased exacerbations and poor health related quality of life (HRQL). Institution based pulmonary rehabilitation programs incorporating airway clearance techniques have been shown to improve HRQL, reduce dyspnoea and improve exercise tolerance but are often difficult to provide due to restricted accessibility and resource implications. This review examines the current evidence base and best clinical practice in the area of airway clearance. Mechanical devices such as the flutter valves, positive end expiratory pressure and high frequency chest wall oscillation (HFCWO) may be able to provide the benefits of improved airway clearance in the patient's home potentially with reduced demands on healthcare resources.

  16. Pharmacometabonomic Prediction of Busulfan Clearance in Hematopoetic Cell Transplant Recipients.

    Science.gov (United States)

    Navarro, Sandi L; Randolph, Timothy W; Shireman, Laura M; Raftery, Daniel; McCune, Jeannine S

    2016-08-01

    Intravenous (IV) busulfan doses are often personalized to a concentration at steady state (Css) using the patient's clearance, which is estimated with therapeutic drug monitoring. We sought to identify biomarkers of IV busulfan clearance using a targeted pharmacometabonomics approach. A total of 200 metabolites were quantitated in 106 plasma samples, each obtained before IV busulfan administration in hematopoietic cell transplant (HCT) recipients. Both univariate linear regression with false discovery rate (FDR) and pathway enrichment analyses using the Global test were performed. In the univariate analysis, glycine, N-acetylglycine, 2-hydroxyisovaleric acid, creatine, serine, and tyrosine were statistically significantly associated with IV busulfan clearance at P 0.1. Glycine is a component of glutathione, which is conjugated with busulfan via glutathione transferase enzymes. These results demonstrate the potential utility of pharmacometabonomics to inform IV busulfan dosing. Future studies are required to validate these findings. PMID:27350098

  17. Bromosulphophthalein clearance rates in sheep with pyrrolizidine liver damage.

    Science.gov (United States)

    Lanigan, G W; Peterson, J E

    1979-05-01

    Sheep fed a ration containing 50% of dried Heliotropium europaeum showed a marked decline in bromosulphophthalein (BSP) fractional clearance rate during the first 3 months feeding. Thereafter, the response of individual animals varied widely on a time basis, although 3 groups could be identified. In the terminal stages, mean clearance rates were below 20% of initial values, with some sheep showing a decline in excess of 90%. Loss of liver functional capacity was generally much greater than indicated by the degree of damage revealed by histopathology. Thus, a suitably modified test could have considerable prognostic value in the field. In this investigation, all sheep with clearance rates below 0.15 died when exposed to a further period of H. europaeum feeding. PMID:475677

  18. Periodic response of multi-disk rotors with bearing clearances

    Science.gov (United States)

    Kim, Y. B.; Noah, S. T.; Choi, Y. S.

    1991-02-01

    The forced steady state response of a multi-disk rotor system involving a clearance at one of the bearings is determined by using a harmonic balance approach. The impedance method is applied to each of the harmonic steady state components in order to reduce the system to its displacement at the non-linear bearing support. The results reveal the interrelated roles of the bearing clearance, mass eccentricity and side force in producing dangerous subharmonics. The significant effects of the strong non-linearity of a bearing clearance are studied as related to the various system parameters. The results show that the approach developed in this study is computationally superior to numerical integration methods in analyzing multi-disk rotor systems with strong non-linearity.

  19. APPLICATION OF DSM IN OBSTACLE CLEARANCE SURVEYING OF AERODROME

    Directory of Open Access Journals (Sweden)

    X. Qiao

    2016-06-01

    Full Text Available Compared to the wide use of digital elevation model (DEM, digital surface model (DSM receives less attention because that it is composed by not only terrain surface, but also vegetations and man-made objects which are usually regarded as useless information. Nevertheless, these objects are useful for the identification of obstacles around an aerodrome. The primary objective of the study was to determine the applicability of DSM in obstacle clearance surveying of aerodrome. According to the requirements of obstacle clearance surveying at QT airport, aerial and satellite imagery were used to generate DSM, by means of photogrammetry, which was spatially analyzed with the hypothetical 3D obstacle limitation surfaces (OLS to identify the potential obstacles. Field surveying was then carried out to retrieve the accurate horizontal position and height of the obstacles. The results proved that the application of DSM could make considerable improvement in the efficiency of obstacle clearance surveying of aerodrome.

  20. Effect of Internal Clearance on Load Distribution and Life of Radially Loaded Ball and Roller Bearings

    Science.gov (United States)

    Oswald, Fred B.; Zaretsky, Erwin V.; Poplawski, Joseph V.

    2012-01-01

    The effect of internal clearance on radially loaded deepgroove ball and cylindrical roller bearing load distribution and fatigue life was determined for four clearance groups defined in the bearing standards. The analysis was extended to negative clearance (interference) conditions to produce a curve of life factor versus internal clearance. Rolling-element loads can be optimized and bearing life maximized for a small negative operating clearance. Life declines gradually with positive clearance and rapidly with increasing negative clearance. Relationships were found between bearing life and internal clearance as a function of ball or roller diameter, adjusted for load. Results are presented as life factors for radially loaded bearings independent of bearing size or applied load. In addition, a modified Stribeck Equation is presented that relates the maximum rolling-element load to internal bearing clearance.

  1. Mucociliary clearance, airway inflammation and nasal symptoms in urban motorcyclists

    Directory of Open Access Journals (Sweden)

    Tereza C.S. Brant

    2014-01-01

    Full Text Available OBJECTIVES: There is evidence that outdoor workers exposed to high levels of air pollution exhibit airway inflammation and increased airway symptoms. We hypothesized that these workers would experience increased airway symptoms and decreased nasal mucociliary clearance associated with their exposure to air pollution. METHODS: In total, 25 non-smoking commercial motorcyclists, aged 18-44 years, were included in this study. These drivers work 8-12 hours per day, 5 days per week, driving on urban streets. Nasal mucociliary clearance was measured by the saccharine transit test; airway acidification was measured by assessing the pH of exhaled breath condensate; and airway symptoms were measured by the Sino-nasal Outcome Test-20 questionnaire. To assess personal air pollution exposure, the subjects used a passive-diffusion nitrogen dioxide (NO2 concentration-monitoring system during the 14 days before each assessment. The associations between NO2 and the airway outcomes were analyzed using the Mann-Whitney test and the Chi-Square test. Clinicaltrials.gov: NCT01976039. RESULTS: Compared with clearance in healthy adult males, mucociliary clearance was decreased in 32% of the motorcyclists. Additionally, 64% of the motorcyclists had airway acidification and 92% experienced airway symptoms. The median personal NO2 exposure level was 75 mg/m3 for these subjects and a significant association was observed between NO2 and impaired mucociliary clearance (p = 0.036. CONCLUSION: Non-smoking commercial motorcyclists exhibit increased airway symptoms and airway acidification as well as decreased nasal mucociliary clearance, all of which are significantly associated with the amount of exposure to air pollution.

  2. Effect of oral N-acetylcysteine on mucus clearance.

    Science.gov (United States)

    Millar, A B; Pavia, D; Agnew, J E; Lopez-Vidriero, M T; Lauque, D; Clarke, S W

    1985-07-01

    Oral N-acetylcysteine has been advocated as a mucolytic agent for use in chronic bronchitis. We have investigated the effects of regular use of this drug at a dose of 200 mg thrice daily for 4 weeks in nine patients with chronic bronchitis on lung function, lung mucociliary clearance and sputum viscosity in a controlled, double-blind, crossover study. No significant differences were found in lung function, mucociliary clearance curves or sputum viscosity following treatment with N-acetylcysteine compared to control or placebo measurements.

  3. The influence of body posture on lithium clearance

    DEFF Research Database (Denmark)

    Kamper, A L; Strandgaard, S; Holstein-Rathlou, N H;

    1988-01-01

    fall in the sitting position, and fell significantly to 26 +/- 5 ml/min (p less than 0.025) in walking subjects. Absolute proximal tubular reabsorption rate of fluid correspondingly rose from 83 +/- 16 to 92 +/- 15 ml/min (p less than 0.005) and sodium clearance fell from 1.52 +/- 0.81 to 1.00 +/- 0...... during moderate physical activity. Hence, when renal tubular function is studied with the lithium clearance method, standardization of posture and physical activity is important. In such studies physical activity such as walking should particularly be avoided....

  4. Derivation methods for clearance levels applied to reactors

    Energy Technology Data Exchange (ETDEWEB)

    Okoshi, Minoru; Seki, Takeo [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2001-12-01

    In order to support the discussion by the Nuclear Safety Commission, JAERI derived the unconditional clearance levels for concrete and metal arising from the operation and dismantling of nuclear reactors. The clearance levels of 20 radionuclides were derived from 10 {mu}Sv/y of individual doses by deterministic approach. In this approach, calculation models were established to assess individual doses resulting from 73 exposure pathways related to disposal and recycle/reuse, and realistic parameter values were selected considering Japanese natural and social conditions. The appropriateness of selected parameter values was confirmed by stochastic analyses. (author)

  5. 轴承游隙计算分析%Analysis and calculation of bearing clearance

    Institute of Scientific and Technical Information of China (English)

    郭玉朋

    2014-01-01

    This paper analyzes the original common bearing clearance, installation clearance,clearance work,what used to solve bearing in C0,C3 clearance clearance work group size,select the project for future reference bearing clearance.%本文通过分析常用轴承的原始游隙,安装游隙,工作游隙,来求解一下常用轴承在C0,C3游隙组中的工作游隙的大小,作为以后项目选取轴承游隙的参考。

  6. Mucociliary and cough clearance as a biomarker for therapeutic development

    DEFF Research Database (Denmark)

    Bennett, William D; Daviskas, Evangelia; Hasani, Amir;

    2010-01-01

    A workshop/symposium on “Mucociliary and Cough Clearance (MCC/CC) as a Biomarker for Therapeutic Development” was held on October 21–22, 2008, in Research Triangle Park, NC, to discuss the methods for measurement of MCC/CC and how they may be optimized for assessing new therapies designed...

  7. Highly fluorescent resorcinarene cavitand nanocapsules with efficient renal clearance

    Science.gov (United States)

    Mahadevan, Kalpana; Patthipati, Venkata Suresh; Han, Sangbum; Swanson, R. James; Whelan, Eoin C.; Osgood, Christopher; Balasubramanian, Ramjee

    2016-08-01

    Nanomaterial based imaging approaches hold substantial promise in addressing current diagnostic and therapeutic challenges. One of the key requirements for the successful clinical translation of nanomaterials is their complete clearance from the body within a reasonable time period preferably via the renal filtration route. This article describes the synthesis of highly fluorescent, water soluble, resorcinarene cavitand nanocapsules and demonstrates their effective renal clearance in mice. The synthesis and functionalization of nanocapsules was accomplished in a one-pot operation via thiol-ene reactions without involving self-assembly, sacrificial templates or emulsions. Water soluble resorcinarene cavitand nanocapsules obtained by this approach were covalently functionalized with Alexa Fluor 750. Highly fluorescent nanocapsules with hydrodynamic diameters of 122 nm and 68 nm and extinction coefficients of 1.3 × 109 M-1 cm-1 and 1.5 × 108 M-1 cm-1 respectively were prepared by varying the reaction conditions. The in vivo biodistribution and clearance of these nanocapsules in mice followed by whole-body fluorescence imaging showed that they were both cleared renally within a few hours. Given the inherent encapsulation capabilities of nanocapsules, the renal clearance demonstrated in this work opens up new opportunities for their theranostic applications especially for targeting and treating the urinary tract.

  8. Decreased renal clearance of digoxin in chronic congestive heart failure.

    Science.gov (United States)

    Naafs, M A; van der Hoek, C; van Duin, S; Koorevaar, G; Schopman, W; Silberbusch, J

    1985-01-01

    Renal digoxin clearance was compared in patients suffering from atrial fibrillation with well preserved cardiac function (n = 9; salt intake +/- 170 mmol daily) and patients with chronic congestive heart failure (n = 10; salt intake 50 mmol daily and maintenance treatment with diuretics). There was no difference between the groups concerning digoxin dosage, creatinine clearance, diuresis or sodium excretion in the urine. Digoxin clearance in chronic heart failure proved to be significantly lower than in atrial fibrillation (48 +/- 21 vs 71 +/- 36 ml X min-1, p less than 0.05), and Cdig/Ccreat was similarly reduced at 0.73 +/- 0.15 compared to 1.09 +/- 0.27 (p less than 0.005). Steady state serum digoxin concentration was significantly higher in patients with congestive heart failure (1.44 +/- 0.47 vs 0.87 +/- 0.33 micrograms X 1(-1), p less than 0.01). Chronic congestive heart failure is a state with reduced digoxin clearance by the kidney, which could lead to digoxin intoxication not explicable by overdose, reduced renal function or the effect of interacting drugs. PMID:4007028

  9. In Vivo Renal Clearance, Biodistribution, Toxicity of Gold nanoclusters

    CERN Document Server

    Zhang, Xiao-Dong; Shen, Xiu; Liu, Pei-Xun; Fan, Fei-Yue; Fan, Sai-Jun; 10.1016/j.biomaterials.2012.03.020

    2012-01-01

    Gold nanoparticles have shown great prospective in cancer diagnosis and therapy, but they can not be metabolized and prefer to accumulate in liver and spleen due to their large size. The gold nanoclusters with small size can penetrate kidney tissue and have promise to decrease in vivo toxicity by renal clearance. In this work, we explore the in vivo renal clearance, biodistribution, and toxicity responses of the BSA- and GSH-protected gold nanoclusters for 24 hours and 28 days. The BSA-protected gold nanoclusters have low-efficient renal clearance and only 1% of gold can be cleared, but the GSH-protected gold nanoclusters have high-efficient renal clearance and 36 % of gold can be cleared after 24 hours. The biodistribution further reveals that 94% of gold can be metabolized for the GSH-protected nanoclusters, but only less than 5% of gold can be metabolized for the BSA-protected nanoclusters after 28 days. Both of the GSH- and BSA-protected gold nanoclusters cause acute infection, inflammation, and kidney fu...

  10. Early clearance of Mycobacterium tuberculosis: a new frontier in prevention

    NARCIS (Netherlands)

    Verrall, A.J.; Netea, M.G.; Alisjahbana, B.; Hill, P.C.; Crevel, R. van

    2014-01-01

    Early clearance (EC) is the successful eradication of inhaled Mycobacterium tuberculosis before an adaptive immune response develops. Evidence for EC comes from case contact studies that consistently show that a proportion of heavily exposed individuals do not develop M. tuberculosis infection. Furt

  11. 46 CFR 61.20-23 - Tailshaft clearance; bearing weardown.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Tailshaft clearance; bearing weardown. 61.20-23 Section...; bearing weardown. (a) Water lubricated bearings, other than rubber, must be rebushed as follows: (1) Where the propelling machinery is located amidship, the after stern tube bearing must be rebushed when it...

  12. Spontaneous Clearance of Hepatitis C after Liver and Renal Transplantation

    Directory of Open Access Journals (Sweden)

    CH Dale

    2009-01-01

    Full Text Available Spontaneous clearance of hepatitis C virus (HCV is rare in immunocompromised patients, such as those who have undergone organ transplantation. It has been recognized that patients receiving liver transplantation for HCV-related disease have decreased graft and patient survival compared with those transplanted for other etiologies. There is a growing trend toward treating HCV recurrence aggressively after liver transplantation. For other organ transplant recipients with concurrent HCV, treatment is not often an option, given the high rates of graft rejection and loss secondary to interferon and its immunomodulatory effects. Although spontaneous clearance of HCV has been reported in recipients of solitary liver and renal transplants, a common factor arising in these cases has been previous exposure to interferon. To date, no reports of spontaneous clearance of HCV RNA have been reported in a multiorgan transplant recipient. A case of spontaneous clearance of HCV RNA in an immunocompromised patient, within five months of simultaneous liver and kidney retransplantation is described. Importantly, this patient had no previous exposure to interferon.

  13. Mucociliary clearance, airway inflammation and nasal symptoms in urban motorcyclists

    OpenAIRE

    Brant, Tereza C S; Yoshida, Carolina T; Tomas de S. Carvalho; Nicola, Marina L; Jocimar. A. Martins; Lays M. Braga; Regiani C. de Oliveira; Vilma Leyton; Carmen S. de André; Saldiva, Paulo H. N.; Rubin, Bruce K.; Naomi K. Nakagawa

    2014-01-01

    OBJECTIVES: There is evidence that outdoor workers exposed to high levels of air pollution exhibit airway inflammation and increased airway symptoms. We hypothesized that these workers would experience increased airway symptoms and decreased nasal mucociliary clearance associated with their exposure to air pollution. METHODS:...

  14. Influence of clearance model on numerical simulation of centrifugal pump

    Science.gov (United States)

    Wang, Z.; Gao, B.; Yang, L.; Du, W. Q.

    2016-05-01

    Computing models are always simplified to save the computing resources and time. Particularly, the clearance that between impeller and pump casing is always ignored. But the completer model is, the more precise result of numerical simulation is in theory. This paper study the influence of clearance model on numerical simulation of centrifugal pump. We present such influence via comparing performance, flow characteristic and pressure pulsation of two cases that the one of two cases is the model pump with clearance and the other is not. And the results show that the head decreases and power increases so that efficiency decreases after computing with front and back cavities. Then no-leakage model would improve absolute velocity magnitude in order to reach the rated flow rate. Finally, more disturbance induced by front cavity flow and wear-ring flow would change the pressure pulsation of impeller and volute. The performance of clearance flow is important for the whole pump in performance, flow characteristic, pressure pulsation and other respects.

  15. 19 CFR 4.61 - Requirements for clearance.

    Science.gov (United States)

    2010-04-01

    ... either on the Customs Form 1300 or by approved electronic means. Customs port directors may permit the.... Customs may take local resources into consideration in allowing clearance to be transacted on board... thereto by any means of communication that is satisfactory to the local Customs port director, and...

  16. Modifications of lung clearance mechanisms by acute influenza A infection

    International Nuclear Information System (INIS)

    Four volunteers with naturally acquired, culture-proved influenza A infection inhaled a radiolabeled aerosol to permit investigation of lung mucociliary clearance mechanisms during and after symptomatic illness. Mucus transport in the trachea was undetectable when monitored with an external multidetector probe within 48 hours of the onset of the illness, but was found at a normal velocity by 1 week in three of the four subjects. In two volunteers who coughed 23 to 48 times during the 4.5-hour observation period, whole lung clearance was as fast within the first 48 hours of illness as during health 3 months later in spite of the absence of measurable tracheal mucus transport. Conversely, in spite of the return 1 week later of mucus transport at velocities expected in the trachea, whole lung clearance for the 4.5-hour period was slowed in two volunteers who coughed less than once an hour. The data offer evidence that cough is important in maintaining lung clearance for at least several days after symptomatic influenza A infection when other mechanisms that depend on ciliary function are severely deficient

  17. Effect of lindane on the clearance rate of Daphnia magna

    NARCIS (Netherlands)

    Hartgers, E.M.; Heugens, E.W.; Deneer, J.W.

    1999-01-01

    The impact of the insecticide lindane (%-hexachlorocyclohexane) on the clearance rate (CR) of Daphnia magna was investigated using artificial beads. CR (24-h EC50: 65 7g Lm1) was found to be a more sensitive endpoint than acute lethality for D. magna (48-h LC50: 516 7g Lm1). The onset of the effect

  18. 75 FR 52798 - State-07, Cryptographic Clearance Records

    Science.gov (United States)

    2010-08-27

    ...: Unclassified. SYSTEM LOCATION: Department of State, 301 4th St., SW., Room 750 Washington, DC 20547. CATEGORIES... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF STATE State-07, Cryptographic Clearance Records Summary: Notice is hereby given that the Department of State proposes to...

  19. CLEARANCE OF INDOMETHACIN OCCURS PREDOMINANTLY BY RENAL GLUCURONIDATION

    NARCIS (Netherlands)

    MOOLENAAR, F; CRANCRINUS, S; VISSER, J; DEZEEUW, D; MEIJER, DKF

    1992-01-01

    In this report we describe the conditions of collection, storage and handling of urine samples, collected after oral dosing with indometacin in man, in order to maintain the integrity of the labile glucuronide formed. We found that the body clearance occurs predominantly by renal metabolism, due to

  20. Metabolism of nanomaterials in vivo: blood circulation and organ clearance.

    Science.gov (United States)

    Wang, Bing; He, Xiao; Zhang, Zhiyong; Zhao, Yuliang; Feng, Weiyue

    2013-03-19

    Before researchers apply nanomaterials (NMs) in biomedicine, they need to understand the blood circulation and clearance profile of these materials in vivo. These qualities determine the balance between nanomaterial-induced activity and unwanted toxicity. NMs have heterogeneous characteristics: they combine the bulk properties of solids with the mobility of molecules, and their highly active contact interfaces exhibit diverse functionalities. Any new and unexpected circulation features and clearance patterns are of great concern in toxicological studies and pharmaceutical screens. A number of studies have reported that NMs can enter the bloodstream directly during their application or indirectly via inhalation, ingestion, and dermal exposure. Due to the small size of NMs, the blood can then transport them throughout the circulation and to many organs where they can be stored. In this Account, we discuss the blood circulation and organ clearance patterns of NMs in the lung, liver, and kidney. The circulation of NMs in bloodstream is critical for delivery of inhalable NMs to extrapulmonary organs, the delivery of injectable NMs, the dynamics of tissue redistribution, and the overall targeting of drug carriers to specific cells and organs. The lung, liver, and kidney are the major distribution sites and target organs for NMs exposure, and the clearance patterns of NMs in these organs are critical for understanding the in vivo fate of NMs. Current studies suggest that multiple factors control the circulation and organ clearance of NMs. The size, shape, surface charge, surface functional groups, and aspect ratio of NMs as well as tissue microstructures strongly influence the circulation of NMs in bloodstream, their site-specific extravasation, and their clearance profiles within organs. Therefore structure design and surface modification can improve biocompatibility, regulate the in vivo metabolism, and reduce the toxicity of NMs. The biophysicochemical interactions

  1. 77 FR 19673 - Proposed Collection; Comment Request; Generic Clearance To Conduct Voluntary Customer/Partner...

    Science.gov (United States)

    2012-04-02

    ... HUMAN SERVICES National Institutes of Health Proposed Collection; Comment Request; Generic Clearance To... and Budget (OMB) for review and approval. Proposed Collection: Title: Generic Clearance to Conduct... strategy in ] accomplishing reinvention goals is the ability to periodically receive input and...

  2. A comparison of analytic procedures for measurement of fractional dextran clearances

    NARCIS (Netherlands)

    Hemmelder, MH; de Jong, PE; de Zeeuw, D

    1998-01-01

    Fractional dextran clearances have been extensively used to study glomerular size selectivity. We report on an analysis of different laboratory procedures involved in measuring fractional dextran clearances. The deproteinization of plasma samples by 20% trichloroacetic acid (TCA) revealed a protein

  3. 19 CFR 122.66 - Clearance or permission to depart denied.

    Science.gov (United States)

    2010-04-01

    ...; DEPARTMENT OF THE TREASURY AIR COMMERCE REGULATIONS Clearance of Aircraft and Permission To Depart § 122.66 Clearance or permission to depart denied. If advance electronic air cargo information is not received...

  4. Consumer Response to Seasonal Clearance Sales: Experimental Analysis of Consumer Personality Traits in Self Service Stores

    OpenAIRE

    Rajagopal, MR

    2006-01-01

    Consumer responses to clearance sales, both in terms of consumer satisfaction with the decision process and in terms of subsequent store choice behavior, are explored in the paper through four controlled experiments conducted involving clearance sales in a consumer choice and decision satisfaction context. The results suggest that consumer response to clearance sales is driven to a large extent by two factors: the effect of a clearance sale on the available options of goods and the degree of ...

  5. 77 FR 66794 - Proposed Information Collection; Comment Request; Generic Clearance for Master Address File (MAF...

    Science.gov (United States)

    2012-11-07

    ... of each activity conducted. The generic clearance enables OMB to review our overall strategy for MTdb... Census Bureau Proposed Information Collection; Comment Request; Generic Clearance for Master Address File... ). SUPPLEMENTARY INFORMATION: I. Abstract The Census Bureau presently operates a generic clearance...

  6. 48 CFR 245.7101-4 - DD Form 1640, Request for Plant Clearance.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false DD Form 1640, Request for Plant Clearance. 245.7101-4 Section 245.7101-4 Federal Acquisition Regulations System DEFENSE... Forms 245.7101-4 DD Form 1640, Request for Plant Clearance. Use to request plant clearance assistance...

  7. Whole body and regional clearances of noradrenaline and adrenaline in man

    DEFF Research Database (Denmark)

    Christensen, N J; Galbo, H; Gjerris, A;

    1984-01-01

    we found no correlation between clearance values based on venous and arterial sampling. In other experiments we measured the influence of physical exercise in young healthy subjects on the clearance rate of plasma adrenaline (A). The clearance of A, which at rest averaged 1.9 l/min tended to increase...

  8. 77 FR 28625 - Comment Request for Information Collection for the Agricultural and Food Processing Clearance...

    Science.gov (United States)

    2012-05-15

    ... Food Processing Clearance Order, ETA Form 790, Extension With Revisions, and the Agricultural and Food... employers must use the Agricultural and Food Processing Clearance Order, ETA Form 790, to list the job... Agricultural and Food Processing Clearance Memorandum, ETA Form 795, is used by SWAs to extend job...

  9. The relationship between the renal clearance of creatinine and the apparent renal clearance of beta-2-microglobulin in patients with normal and impaired kidney function.

    Science.gov (United States)

    Vree, T B; Guelen, P J; Jongman-Nix, B; Walenkamp, G H

    1981-07-18

    The renal clearances of creatinine and beta 2-microglobulin of patients with either normal or impaired kidney function were measured. The renal clearance of beta 2-microglobulin depends on the urinary pH and must be considered as an apparent renal clearance because after tubular reabsorption the compound is metabolized in the kidney. Impaired kidney function reduces the percentage of tubular reabsorption of beta 2-microglobulin. PMID:6166414

  10. Nanoparticle clearance from the airways : development and testing of a new in vitro model to investigate mucociliary clearance of aerosol particles

    OpenAIRE

    Henning, Andreas Michael

    2008-01-01

    The current challenge in pulmonary drug delivery is to overcome and to control drug clearance from the lung. Here, the interaction with the mucociliary lung clearance plays a key role for any drug formulation technology. By today many open questions on mucociliary clearance (MC) have to be answered but suffer from limited experimental options. Considering these facts, the central part of this work was to develop a new in vitro test model to investigate the complex mechanism of MC more detaile...

  11. Numerical analysis of bump foil bearings without nominal radial clearance

    Institute of Scientific and Technical Information of China (English)

    LIU Zhan-sheng; XU Huai-jin; ZHANG Guang-hui

    2008-01-01

    Bump foil bearings without nominal radial clearance were analyzed. An air film thickness model and a bearing theoretical analytical model were developed accounting for air compressibility and foil deformation. To analyze hydrodynamic characteristics of bump foil beatings with different operating eccentricities, the air film thickness equation and Reynolds equation were coupled through pressure and solved by Newton-Raphson Method(NRM) and Finite Difference Method (FDM). The characteristics of an bump foil bearing model were dis-cussed including load carrying capacity, film thickness and pressure distributions. The results of simulation show that bump foil beating without nominal radial clearance can provide better stability and greater load capaci-ty. This numerical analytical method also reveals a good convergence in numerical calculation.

  12. Apoptotic cell clearance: basic biology and therapeutic potential.

    Science.gov (United States)

    Poon, Ivan K H; Lucas, Christopher D; Rossi, Adriano G; Ravichandran, Kodi S

    2014-03-01

    The prompt removal of apoptotic cells by phagocytes is important for maintaining tissue homeostasis. The molecular and cellular events that underpin apoptotic cell recognition and uptake, and the subsequent biological responses, are increasingly better defined. The detection and disposal of apoptotic cells generally promote an anti-inflammatory response at the tissue level, as well as immunological tolerance. Consequently, defects in apoptotic cell clearance have been linked with various inflammatory diseases and autoimmunity. Conversely, under certain conditions, such as the killing of tumour cells by specific cell-death inducers, the recognition of apoptotic tumour cells can promote an immunogenic response and antitumour immunity. Here, we review the current understanding of the complex process of apoptotic cell clearance in physiology and pathology, and discuss how this knowledge could be harnessed for new therapeutic strategies.

  13. [Amylase-creatinine clearance ratios in burned patients (author's transl)].

    Science.gov (United States)

    Minaire, Y; Marichy, J; Forichon, J; Motin, J

    1978-09-01

    The amylase/creatinine clearance ratio (ACCR) has been examined every 3 days, in 34 burned patients during the 20 days following the accident. This ratio was often abnormal since it was found increased at least on one occasion, in 75% of these patients, to be compared with 23 and 13% for amylase in serum and urine respectively. In another group of 9 burned patients, the ACCR was monitored for time-period between 10 to 52 days. It was observed that a high frequency in increased ACCR was associated with a fatal outcome. Finally simultaneous measurements of ACCR and of the beta2 microglobulin/creatinine clearance ratio (MCCR) showed that increased ACCR were statistically associated with increased MCCR suggesting a decreased renal tubular reabsorption of low molecular weight proteins in these burned patients.

  14. [Amylase-creatinine clearance ratios in burned patients (author's transl)].

    Science.gov (United States)

    Minaire, Y; Marichy, J; Forichon, J; Motin, J

    1978-09-01

    The amylase/creatinine clearance ratio (ACCR) has been examined every 3 days, in 34 burned patients during the 20 days following the accident. This ratio was often abnormal since it was found increased at least on one occasion, in 75% of these patients, to be compared with 23 and 13% for amylase in serum and urine respectively. In another group of 9 burned patients, the ACCR was monitored for time-period between 10 to 52 days. It was observed that a high frequency in increased ACCR was associated with a fatal outcome. Finally simultaneous measurements of ACCR and of the beta2 microglobulin/creatinine clearance ratio (MCCR) showed that increased ACCR were statistically associated with increased MCCR suggesting a decreased renal tubular reabsorption of low molecular weight proteins in these burned patients. PMID:360162

  15. Guangzhou Customs Guide to "Local Declaration & Port Clearance"

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    @@ Ⅰ.Characteristic of the supervision mode of "Local Declaration & Port Clearance" This new mode means that the consignor,consignee or agent (hereafter referred to as "declarant") could choose any competent customs under the jurisdiction of Guangzhou Customs to make declaration and go through the formalities of document-checking and duty-paying,and then finish the cargo-examination and cargo-release at the customs office of entry or exit.

  16. Surface code—biophysical signals for apoptotic cell clearance

    Science.gov (United States)

    Biermann, Mona; Maueröder, Christian; Brauner, Jan M.; Chaurio, Ricardo; Janko, Christina; Herrmann, Martin; Muñoz, Luis E.

    2013-12-01

    Apoptotic cell death and the clearance of dying cells play an important and physiological role in embryonic development and normal tissue turnover. In contrast to necrosis, apoptosis proceeds in an anti-inflammatory manner. It is orchestrated by the timed release and/or exposure of so-called ‘find-me’, ‘eat me’ and ‘tolerate me’ signals. Mononuclear phagocytes are attracted by various ‘find-me’ signals, including proteins, nucleotides, and phospholipids released by the dying cell, whereas the involvement of granulocytes is prevented via ‘stay away’ signals. The exposure of anionic phospholipids like phosphatidylserine (PS) by apoptotic cells on the outer leaflet of the plasma membrane is one of the main ‘eat me’ signals. PS is recognized by a number of innate receptors as well as by soluble bridging molecules on the surface of phagocytes. Importantly, phagocytes are able to discriminate between viable and apoptotic cells both exposing PS. Due to cytoskeleton remodeling PS has a higher lateral mobility on the surfaces of apoptotic cells thereby promoting receptor clustering on the phagocyte. PS not only plays an important role in the engulfment process, but also acts as ‘tolerate me’ signal inducing the release of anti-inflammatory cytokines by phagocytes. An efficient and fast clearance of apoptotic cells is required to prevent secondary necrosis and leakage of intracellular danger signals into the surrounding tissue. Failure or prolongation of the clearance process leads to the release of intracellular antigens into the periphery provoking inflammation and development of systemic inflammatory autoimmune disease like systemic lupus erythematosus. Here we review the current findings concerning apoptosis-inducing pathways, important players of apoptotic cell recognition and clearance as well as the role of membrane remodeling in the engulfment of apoptotic cells by phagocytes.

  17. Surface code—biophysical signals for apoptotic cell clearance

    International Nuclear Information System (INIS)

    Apoptotic cell death and the clearance of dying cells play an important and physiological role in embryonic development and normal tissue turnover. In contrast to necrosis, apoptosis proceeds in an anti-inflammatory manner. It is orchestrated by the timed release and/or exposure of so-called ‘find-me’, ‘eat me’ and ‘tolerate me’ signals. Mononuclear phagocytes are attracted by various ‘find-me’ signals, including proteins, nucleotides, and phospholipids released by the dying cell, whereas the involvement of granulocytes is prevented via ‘stay away’ signals. The exposure of anionic phospholipids like phosphatidylserine (PS) by apoptotic cells on the outer leaflet of the plasma membrane is one of the main ‘eat me’ signals. PS is recognized by a number of innate receptors as well as by soluble bridging molecules on the surface of phagocytes. Importantly, phagocytes are able to discriminate between viable and apoptotic cells both exposing PS. Due to cytoskeleton remodeling PS has a higher lateral mobility on the surfaces of apoptotic cells thereby promoting receptor clustering on the phagocyte. PS not only plays an important role in the engulfment process, but also acts as ‘tolerate me’ signal inducing the release of anti-inflammatory cytokines by phagocytes. An efficient and fast clearance of apoptotic cells is required to prevent secondary necrosis and leakage of intracellular danger signals into the surrounding tissue. Failure or prolongation of the clearance process leads to the release of intracellular antigens into the periphery provoking inflammation and development of systemic inflammatory autoimmune disease like systemic lupus erythematosus. Here we review the current findings concerning apoptosis-inducing pathways, important players of apoptotic cell recognition and clearance as well as the role of membrane remodeling in the engulfment of apoptotic cells by phagocytes. (paper)

  18. Mathematical modeling and analysis of insulin clearance in vivo

    OpenAIRE

    Koschorreck, Markus; Gilles, Ernst Dieter

    2008-01-01

    Background Analyzing the dynamics of insulin concentration in the blood is necessary for a comprehensive understanding of the effects of insulin in vivo. Insulin removal from the blood has been addressed in many studies. The results are highly variable with respect to insulin clearance and the relative contributions of hepatic and renal insulin degradation. Results We present a dynamic mathematical model of insulin concentration in the blood and of insulin receptor activation in hepatocytes. ...

  19. Mathematical modeling and analysis of insulin clearance in vivo

    OpenAIRE

    Koschorreck, M.; Gilles, E. D.

    2008-01-01

    Background: Analyzing the dynamics of insulin concentration in the blood is necessary for a comprehensive understanding of the effects of insulin in vivo. Insulin removal from the blood has been addressed in many studies. The results are highly variable with respect to insulin clearance and the relative contributions of hepatic and renal insulin degradation. Results: We present a dynamic mathematical model of insulin concentration in the blood and of insulin receptor acti...

  20. Mathematical modeling and analysis of insulin clearance in vivo

    OpenAIRE

    Koschorreck, M.; Gilles, E.

    2008-01-01

    Background: Analyzing the dynamics of insulin concentration in the blood is necessary for a comprehensive understanding of the effects of insulin in vivo. Insulin removal from the blood has been addressed in many studies. The results are highly variable with respect to insulin clearance and the relative contributions of hepatic and renal insulin degradation. Results: We present a dynamic mathematical model of insulin concentration in the blood and of insulin receptor activation in hepatocytes...

  1. Lung Clearance Index bei erwachsenen Patienten mit Mukoviszidose

    OpenAIRE

    Rückel, Helena Sophie

    2011-01-01

    Die Spirometrie mit Bestimmung des forcierten exspiratorischen Volumens in einer Sekunde gilt derzeit als Gold-Standard bei der Beurteilung der Lungenfunktion von Patienten mit Cystischer Fibrose. Da die spirometrische Untersuchung eine aktive Mitarbeit des Patienten erfordert, kann sie jedoch erst etwa ab dem fünften Lebensjahr durchgeführt werden. Im Gegensatz dazu kann der Lung Clearance Index (LCI), der aus Gasdilutionsuntersuchungen abgeleitet wird, in jedem Alter, d.h. auch im Säugl...

  2. Respiratory Protection Program medical clearance for respirator use

    Science.gov (United States)

    1993-01-01

    Background on occupational exposure to various inhalents is discussed including on-site hazard control measures, procedures, physiological effects, and interpretation of results for the medical clearance of employee for use of personal respiratory protection devices. The purpose of the Respiratory Protection Program at LeRC is outlined, and the specifics of the Medical Surveillance Program for Respiratory Protection at LeRC are discussed.

  3. Apoptotic clearance in rabbits with experimental pulmonary emphysema

    OpenAIRE

    Žunić-Božinovski Snežana; Žunić Svetlana; Mladenović-Đorđević Aleksandra; Ruždijić Sabera; Kanazir Selma

    2011-01-01

    In order to better understand pathogenesis of pulmonary emphysema, the model of experimentally induced pulmonary emphysema in Chinchilla rabbits was used for the estimation of apoptotic clearance of pulmonary tissue. Bronchoalveolar lavage was performed in three groups of animals: experimental group-E on hypercholesterolemic diet (4% edible oil solution of crystalline cholesterol), control group-C1 on standard diet for that animal species and animals on oil...

  4. Early clearance of pneumococci from the lungs of decomplemented rats.

    OpenAIRE

    Rehm, S R; Coonrod, J D

    1982-01-01

    Pneumococcal types which exhibited varying degrees of interaction with the complement system in vitro wee aerosolized into normal and decomplemented rats, and the rate of killing of pneumococci was monitored by serial cultures of whole lung homogenates. The clearance of pneumococci from the alveoli did not correlate with the ability of the pneumococci to be opsonized by complement in vitro. Similarly, rats depleted of complement in the serum and the bronchoalveolar lavage fluid maintained the...

  5. Mine clearance industry: background, geography, funding, analysis and future projections

    OpenAIRE

    Donmez, Erkan

    2007-01-01

    MBA Professional Report Approved for public release; distribution is unlimited Contrary to common belief, the problems caused by landmines or other counter mobility devices have been threatening the lives of human beings for thousands of years. However, the actual efforts to remove the buried mines are a comparatively new issue. The mine clearance industry has been growing steadily, mostly because of increasing demand from the mine-afflicted countries, NGOs, international organizati...

  6. Highly Catalytic Nanodots with Renal Clearance for Radiation Protection

    OpenAIRE

    Zhang, Xiao-Dong; Zhang, Jinxuan; Wang, Junying; Yang, Jiang; Chen, Jie; Shen, Xiu; Deng, Jiao; Deng, Dehui; Long, Wei; Sun, Yuan-Ming; Liu, Changlong; Li, Meixian

    2016-01-01

    Ionizing radiation (gamma and x-ray) is widely used in industry and medicine, but it can also pose a significant hazardous effect on health and induce cancer, physical deformity and even death, due to DNA damages and invasion of free radicals. There is therefore an urgent unmet demand in designing highly efficient radioprotectants with synergetic integration of effective renal clearance and low toxicity. In this study, we designed ultrasmall (sub-5 nm) highly catalytically active and cysteine...

  7. Comparison of Two Alternate Methods for Tracking Toe Clearance

    Science.gov (United States)

    Miller, Christopher A.; Feiveson, Alan H.; Bloomberg, Jacob J.

    2007-01-01

    Analyses of toe clearance during the swing phase of locomotion has often been utilized in determining a subject s propensity to trip while either walking or stepping over an obstacle. In the literature, toe clearance has been studied using a marker on the superior aspect of the second toe (rtoe), a marker on the lateral aspect of the fifth metatarsal head (mth5), or a virtual marker positioned at the anterior tip of the toe (vtoe). The purpose of this study was to compute toe clearance and associated parameters using a fifth metatarsal marker and a virtual toe marker, and compare the results with those of the standard toe marker. Subjects walked on a motorized treadmill at five different speeds while performing a visual acuity task at two separate target distances (ten 60-second trials). The minimum vertical height (TCl) was determined for each stride, along with its point of occurence in the gait cycle, and the angles of the foot and ankle at that time. A regression analysis was performed on the vtoe and mth5 results versus rtoe individually. For all TCl parameters, the mth5 marker did not correlate well with rtoe; the vtoe marker showed better agreement. Most importantly, the mth5 marker predicted a later occurence of TCl than rtoe and vtoe - thereby missing the most dangerous point in swing phase for a trip. From this analysis, the vtoe marker proved to be a better analog to rtoe than mth5, especially for determining a subject s propensity to trip.

  8. Effect of Guide Vane Clearance Gap on Francis Turbine Performance

    Directory of Open Access Journals (Sweden)

    Ravi Koirala

    2016-04-01

    Full Text Available Francis turbine guide vanes have pivoted support with external control mechanism, for conversion of pressure to kinetic energy and to direct them to runner vanes. This movement along the support is dependent on variation of load and flow (operating conditions. Small clearance gaps between facing plates and the upper and lower guide vane tips are available to aid this movement, through which leakage flow occurs. This secondary flow disturbs the main flow stream, resulting performance loss. Additionally, these increased horseshoe vortex, in presence of sand, when crosses through the gaps, both the surfaces are eroded. This causes further serious effect on performance and structural property by increasing gaps. This paper discusses the observation of the severity in hydropower plants and effect of clearance gaps on general performance of the Francis turbine through computational methods. It also relates the primary result with the empirical relation for leakage flow prediction. Additionally, a possible method to computationally estimate thickness depletion has also been presented. With increasing clearance gap, leakage increases, which lowers energy conversion and turbine efficiency along with larger secondary vortex.

  9. Dysregulation of Nutrient Sensing and CLEARance in Presenilin Deficiency

    Directory of Open Access Journals (Sweden)

    Kavya Reddy

    2016-03-01

    Full Text Available Attenuated auto-lysosomal system has been associated with Alzheimer disease (AD, yet all underlying molecular mechanisms leading to this impairment are unknown. We show that the amino acid sensing of mechanistic target of rapamycin complex 1 (mTORC1 is dysregulated in cells deficient in presenilin, a protein associated with AD. In these cells, mTORC1 is constitutively tethered to lysosomal membranes, unresponsive to starvation, and inhibitory to TFEB-mediated clearance due to a reduction in Sestrin2 expression. Normalization of Sestrin2 levels through overexpression or elevation of nuclear calcium rescued mTORC1 tethering and initiated clearance. While CLEAR network attenuation in vivo results in buildup of amyloid, phospho-Tau, and neurodegeneration, presenilin-knockout fibroblasts and iPSC-derived AD human neurons fail to effectively initiate autophagy. These results propose an altered mechanism for nutrient sensing in presenilin deficiency and underline an importance of clearance pathways in the onset of AD.

  10. RENAL CLEARANCE AND URINARY EXCRETION OF CIPROFLOXACIN IN GOATS

    Directory of Open Access Journals (Sweden)

    Z. IQBAL, I. JAVED, B. ASLAM, F. MUHAMMAD AND I. U. JAN

    2007-10-01

    Full Text Available The renal clearance and urinary excretion of ciprofloxacin were investigated in eight healthy female goats. In each animal, ciprofloxacin was administered intramuscularly at the rate of 5 mg/kg body weight. Following drug administration, blood and urine samples were collected at different time intervals and analyzed for ciprofloxacin and creatinine. High performance liquid chromatography (HPLC was used to determine the drug concentration in the plasma and urine. The value of diuresis after single administration of ciprofloxacin was 0.073 ± 0.014 ml/min/kg. Mean (± SE values for renal clearance of creatinine and ciprofloxacin were 1.870 ± 0.385 and 0.982 ± 0.166 ml/min/kg, respectively. The ratio between the renal clearance of ciprofloxacin and that of creatinine remained less than one, which was indicative of back diffusion. The mean (± SE value for the cumulative percent of ciprofloxacin dose excreted at 10 hours following its intramuscular administration was 13.03 ± 2.07. Based on these results, it was evident that besides glomerular filtration, renal handling of drug involved back diffusion also. It was concluded that in local goats glomerular filtration rate (GFR was lower than that reported for their foreign counterparts.

  11. Smoking produced mucus and clearance of particulates in the lung

    International Nuclear Information System (INIS)

    Some studies of miners have shown a lesser relative lung-cancer risk for smokers than for nonsmokers. For example, experiments by Cross and associates with dogs have shown an apparent protective effect of cigarette smoke against radon-daughter and dust exposure. One reason for these changes may be the thickened mucus layer in the tracheobronchial region of smokers. Physiological changes in the lung due to smoking may decrease the effects of radioactive particles in cancers in the bronchial region by apparently promoting faster clearance, in that region, of radioactive particles and by decreasing the radiation dose through reduced penetration to the sensitive basal epithelial cells. Because of the short half-life of radon daughters, even if there is possible tobacco-related delay of particle clearance from the alveolar region it cannot affect radon clearance. Therefore, the possible mitigating effect of tobacco on radon-produced cancer appears to be limited to the tracheobronchial region. It would be of value to a number of occupations if the same changes in the lungs due to smoking could be produced in exposed workers in the absence of cigarette-smoking. Beta-carotene and vitamin A, which affect maintenance and secretion of the mucosal lining, appear to thicken mucus, thereby providing protection against radon-induced lung cancers that is similar to smoking-related changes in the lung

  12. Respirable industrial fibres: deposition, clearance and dissolution in animal models.

    Science.gov (United States)

    Jones, A D

    1993-04-01

    This paper examines the available experimental and theoretical results describing deposition and clearance of mineral fibres inhaled by animals and humans in order to define the limits which these mechanisms impose on the relevance of animal experiments in the assessment of potential human health risks. Direct experimental data for deposition of spherical particles are extended by examination of the physical processes and by some limited experimental data for fibres. This shows that alveolar deposition efficiency (in rat and in man) is sufficiently similar for particles and fibres with aerodynamic diameters less that 5 microns for rats to be a relevant model for airborne dusts in this size range. Inter-species differences in mechanical clearance are substantial, with clearance being faster in the rat than in man, and this is a factor which should be considered in interpreting animal toxicity studies. The durability of fibres in the biochemical conditions of the lung may be more important over the longer lifespan of humans. PMID:8317856

  13. Numerical investigation of tip clearance effects on the performance of ducted propeller

    Directory of Open Access Journals (Sweden)

    Yongle Ding

    2015-09-01

    Full Text Available Tip clearance loss is a limitation of the improvement of turbomachine performance. Previous studies show the Tip clearance loss is generated by the leakage flow through the tip clearance, and is roughly linearly proportional to the gap size. This study investigates the tip clearance effects on the performance of ducted propeller. The investigation was carried out by solving the Navier-Stokes equations with the commercial Computational Fluid Dynamic (CFD code CFX14.5. These simulations were carried out to determine the underlying mechanisms of the tip clearance effects. The calculations were performed at three different chosen advance ratios. Simulation results showed that the tip loss slope was not linearly at high advance due to the reversed pressure at the leading edge. Three type of vortical structures were observed in the tip clearance at different clearance size.

  14. SOIL QUALITY CHANGES FOLLOWING FOREST CLEARANCE IN BENGKULU, SUMATRA

    Directory of Open Access Journals (Sweden)

    I.P. HANDAYANI

    2004-01-01

    Full Text Available Intense destruction and degradation of tropical forests is recognized as one of the environmental threats and tragedies. These have increased the need to assess the effects of subsequent land-use following forest extraction on soil quality. Therefore, the objective of this study is to evaluate the impacts of land-use type on soil quality properties in Bengkulu Province, Sumatra. Soil samples were collected from adjacent sites including natural secondary forest, bare land, cultivated land and grassland. The results show that land-use following forest clearance lowered saturated hydraulic conductivity (85%, porosity (10.50%, soil water content at field capacity (34%,C organic (27%, N total (26%, inorganic N (37%, soil microbial biomass C (32%, mineralizable C (22%, and particulate organic matter (50%, but slightly increased water soluble organic C. Specific respiration activi ty rates increased about 14% in cultivated soils compared to natural forest soils, indicating greater C turnover per labile C pool in the form of soil microbial biomass, thus decreased biologically active soil organic matter. Forest conversion tends to reduce the C,ffg/Crer for all deforested sites. All of deforested areas relatively have infertile soil, with the worst case found in cultivated field. The C^g/Crd of cultivated field s was about 24% less than that of remnant fo rest (1.07. Grassland apparently mainta ins only slightly higher soil C levels than the bare land. On average, degradation index of so il following forest clearance was 35% with the highest deterioration occurred in the bare land (38%. Fallowing the fields by naturally growth of Imperata cylindrica for about 15 yr in abandoned land after 3-5 years of cultivation did not improve the soil quality. Moreover, forest clearance has an impact on soil quality as resulted in the loss of a physically protected organic matter and reduction in some labile C pools, thus declined biological activity at disturbed

  15. Upregulation of Phagocytic Clearance of Apoptotic Cells by Autoimmune Regulator

    Institute of Scientific and Technical Information of China (English)

    石亮; 胡丽华; 李一荣

    2010-01-01

    To investigate the effect of autoimmune regulator(AIRE) on phagocytic clearance of apoptotic cells,a recombinant expression vector containing full-length human AIRE cDNA was transfected into 16HBE cells.After incubation with transfected 16HBE cells,engulfment of apoptotic HL-60 cells induced by camptothecin was detected by myeloperoxidase(MPO) staining.The change in the expression of Rac 1 in transfected 16HBE cells was determined by RT-PCR and Western blotting.The results showed that the phagocytosis perce...

  16. Clearance of 99mTc-DTPA and experimentally increased alveolar surfactant content

    International Nuclear Information System (INIS)

    The authors measured clearance of 99mTc-labeled diethylenetriamine pentaacetic acid (99mTc-DTPA) in rabbits with experimentally increased alveolar surfactant content. In one group of animals, surfactant production was increased by treatment with ambroxol, and another group of animals was treated with tracheal instillation of natural surfactant. A group of untreated control animals and animals treated with instillation of saline were also studied. Clearance was measured during standard conditions of mechanical ventilation and during ventilation with large tidal volumes. In ambroxol- and surfactant-treated groups, clearance rate was reduced compared with untreated control animals. In contrast, clearance rate increased after saline instillation. The differences were observed at both modes of ventilation. The findings indicate that the pulmonary surfactant system is a rate-limiting factor for the clearance of 99mTc-DTPA and that the volume dependence of clearance is not explained by stretching of the alveolar wall only. 28 refs., 2 figs., 1 tab

  17. Understanding of the Interaction between Clearance Leakage Flow and Main Passage Flow in a VGT Turbine

    Directory of Open Access Journals (Sweden)

    Ben Zhao

    2015-02-01

    Full Text Available The clearance flow between the nozzle and endwall in a variable geometry turbine (VGT has been numerically investigated to understand the clearance effect on the VGT performance and internal flow. It was found that the flow rate through turbine increases but the turbine efficiency decreases with height of clearance. Detailed flow field analyses indicated that most of the efficiency loss resulting from the leakage flow occurs at the upstream of the rotor area, that is, in the nozzle endwall clearance and between the nozzle vanes. There are two main mechanisms associated with this efficiency loss. One is due to the formation of the local vortex flow structure between the clearance flow and the main flow. The other is due to the impact of the clearance flow on the main flow after the nozzle throat. This impact reduces the span of shockwave with increased shockwave magnitude by changing the trajectory of the main flow.

  18. LRP1 in Brain Vascular Smooth Muscle Cells Mediates Local Clearance of Alzheimer's Amyloid-β

    OpenAIRE

    Kanekiyo, Takahisa; Liu, Chia-Chen; Shinohara, Mitsuru; Li, Jie; Bu, Guojun

    2012-01-01

    Impaired clearance of amyloid-β (Aβ) is a major pathogenic event for Alzheimer’s disease (AD). Aβ depositions in brain parenchyma as senile plaques and along cerebrovasculature as cerebral amyloid angiopathy (CAA) are hallmarks of AD. A major pathway that mediates brain Aβ clearance is the cerebrovascular system where Aβ is eliminated through the blood-brain barrier (BBB) and/or degraded by cerebrovascular cells along the interstitial fluid drainage pathway. An Aβ clearance receptor, the low-...

  19. The screening value of the amylase-creatinine clearance ratio in acute pancreatitis.

    Science.gov (United States)

    Van Hee, R; Hubens, A

    1979-01-01

    The screening value of the amylase creatinine clearance ratio in acute pancreatitis is studied. A series of 28 patients with pancreatic disease is compared with 80 controls and 82 patients with other intra-abdominal disease. The greatest specificity of the amylase creatinine clearance ratio value is reached at the 3.5 level. The amylase creatinine clearance ratio value proves to be of interest, not only in the diagnosis of acute pancreatitis but also in differentiating mild and heavy forms of pancreatitis.

  20. Two-phase deep-lung clearance in man

    International Nuclear Information System (INIS)

    For toxicological as well as physiological considerations, it is important to determine whether the long-term clearance of particles from the lungs of man takes place in more than one temporal subphase. Although long-term retention can be characterized with a single exponential, the existence of two distinct components would significantly alter estimates of overall residence times and hence potential effects of inhaled particulates. Physiological interpretations of the mechanisms of long-term particle clearance depend on the identification and quantification of such temporal subphases. A highly sensitive whole-body counter was used to measure the long-term retention of inhaled particles in man. After inhalation of 85Sr, lung retention was monitored in eight volunteers for periods ranging from 197 to 399 days. Their pulmonary-function values fell within normal limits, and they reported no symptoms of lung disease. Four of the individuals had never smoked, and four had not smoked for a minimum of 5 years. Single exponential representation half-times for the long-term retention were comparable between the two groups and were combined to give a mean half-time of 197 +- 32 days

  1. Reduction in slow intercompartmental clearance of urea during dialysis

    Energy Technology Data Exchange (ETDEWEB)

    Bowsher, D.J.; Krejcie, T.C.; Avram, M.J.; Chow, M.J.; Del Greco, F.; Atkinson, A.J. Jr.

    1985-04-01

    The kinetics of urea and inulin were analyzed in five anesthetized dogs during sequential 2-hour periods before, during, and after hemodialysis. The distribution of both compounds after simultaneous intravenous injection was characterized by three-compartment models, and the total volumes of urea (0.66 +/- 0.05 L/kg) and inulin (0.19 +/- 0.01 L/kg) distribution were similar to expected values for total body water and extravascular space, respectively. Intercompartmental clearances calculated before dialysis were used to estimate blood flows to the fast and slow equilibrating compartments. In agreement with previous results, the sum of these flows was similar to cardiac output, averaging 101% of cardiac output measured before dialysis (range 72% to 135%). Dialysis was accompanied by reductions in the slow intercompartmental clearances of urea (81%) and inulin (47%), which reflected a 90% attenuation in blood flow supplying the slow equilibrating compartments. This was estimated to result in a 10% average reduction in the efficiency with which urea was removed by dialysis (range 2.0% to 16.4%). Mean arterial pressure fell by less than 5% during dialysis, but total peripheral resistance increased by 47% and cardiac output fell by 35%. In the postdialysis period, total peripheral resistance and cardiac output returned toward predialysis values, but blood flow to the slow equilibrating peripheral compartment was still reduced by 80%. These changes parallel activation of the renin-angiotensin system, but further studies are required to establish causality.

  2. Radionuclide quantification of oropharyngeal clearance with and without pharyngitis

    Energy Technology Data Exchange (ETDEWEB)

    Robbins, P.S.; Siegel, J.A.; Maurer, A.H.; Schachtel, B.P.; Malmud, L.S.

    1984-01-01

    The purpose of this study was to evaluate a new radionuclide method for quantifying oropharyngeal clearance (C) in 10 otherwise normal patients with and without pharyngitis (PH). Patients with objective evidence of PH initially swallowed 10 ml of water mixed with 1 mCi Tc-99m sulfur colloid and then performed a dry swallow each 15 seconds. This was repeated 1-4 weeks later when there was no evidence of pharyngitis (NP). Images were acquired using a high sensitivity collimator for 0.1 sec/image for 30 sec and 15 sec/image for an additional 270 sec. Time activity curves generated from a region of interest over the oropharynx were fit to a biexponential function, C = Ae/sup -k/1/sup t/ + Be/sup -k/2/sup t/; where A and B are the percent of activity clearing with fast and slow components, k/sub 1/, and k/sub 2/, respectively, with half times 0.693/k/sub l,2/. The T1/2 for the slow component was reproducible for PH and NP. The fast component was slightly prolonged with PH, but not to statistical significance (p>.2). The authors conclude that a biexponential model of clearance may be used to quantify oropharyngeal function, for patients with normal and abnormal swallowing.

  3. The amylase creatinine clearance ratio in acute pancreatitis.

    Science.gov (United States)

    Murray, W R; Mackay, C

    1977-03-01

    One hundred and twenty-two patients have been studied in order to evaluate the usefulness of the amylase creatinine clearance ratio (ACCR) as a simple diagnostic test for acute pancreatitis. Sixteen out of 17 patients with acute pancreatitis had significant elevations in ACCR; in only 10 of these 17 cases was the serum amylase greater than 1200iu/l. The mean ACCR was within the normal range in control patients, in patients with chronic gastro-intestinal disease and in patients with acute abdominal conditions excluding pancreatitis; however, the mean serum amylase was significantly greater in patients with acute abdominal conditions than in the control group (P less than 0-05). The ACCR remained significantly elevated in patients with acute pancreatitis for longer than either serum or urine amylase values. The findings of the study suggest that the amylase creatinine clearance ratio is a simple yet reliable diagnostic test which could be used when screening patients suspected of having acute pancreatitis.

  4. 123I-IMP clearance of the lung in pneumoconiosis

    International Nuclear Information System (INIS)

    We studied 123I-IMP lung clearance on 10 cases of pneumoconiosis and compared it with the data of 5 non-smoking young adults. After the venous injection of 111 MBq of 123I-IMP we collected the lung dynamic data using 1 frame/10 sec for 10 minutes and 1 frame/min for following 40 minutes. The time activity curve after the injection of 123I-IMP was obtained as follows: C(t)=A1e-k1t+A2e-k2t (k1, k2: slopes of the exponential component at the early and delayed phase). The 123I-IMP clearance was delayed in the patients group especially on the early phase and the k1 was lower than that of the normal group. Our results indicate that the pulmonary blood flow of the patients with pneumoconiosis decreased because of the advanced fibrotic change. This dynamic analysis may prove useful for the evaluation of the pneumoconiosis objectively and quantitatively. (author)

  5. Robotic Mounted Detection System: robotics for route clearance

    Science.gov (United States)

    Hutchison, John; Klager, Gene; McCoy, Edward; Fite, David; Frederick, Brian

    2010-04-01

    Robotic Mounted Detection System (RMDS) is a government program to enable robotic control of a Husky route clearance vehicle with a mine detection sensor payload. The goal is for the operator to control the Husky and mine detection sensor from another vehicle. This program will provide the user with standard tele-operation control of the vehicle as well as semi-autonomous modes including cruise control, precision waypoint navigation with operator error correction and a visual mode allowing the operator to enter waypoints in the current video feed. The use of autonomy will be tailored to give the operator maximum control of the robotic vehicle's path while minimizing the effort required to maintain the desired route. Autonomous alterations of the path would conflict with the goal of route clearance, so waypoint navigation will allow the operator to supply offsets to counteract location errors. While following a waypoint path, the Husky will be capable of controlling its speed to maintain an operator specified distance from the control vehicle. Obstacle avoidance will be limited to protecting the mine detection sensor, leaving any decision to leave the path up to the operator. Video will be the primary navigational sensor feed to the operator, who will use an augmented steering wheel controller and computer display to control the Husky. A LADAR system will be used to detect obstacles that could damage the mine sensor and to maintain the optimal sensor orientation while the vehicle is moving. Practical issues and lessons learned during integration will be presented.

  6. The amylase creatinine clearance ratio in acute pancreatitis.

    Science.gov (United States)

    Murray, W R; Mackay, C

    1977-03-01

    One hundred and twenty-two patients have been studied in order to evaluate the usefulness of the amylase creatinine clearance ratio (ACCR) as a simple diagnostic test for acute pancreatitis. Sixteen out of 17 patients with acute pancreatitis had significant elevations in ACCR; in only 10 of these 17 cases was the serum amylase greater than 1200iu/l. The mean ACCR was within the normal range in control patients, in patients with chronic gastro-intestinal disease and in patients with acute abdominal conditions excluding pancreatitis; however, the mean serum amylase was significantly greater in patients with acute abdominal conditions than in the control group (P less than 0-05). The ACCR remained significantly elevated in patients with acute pancreatitis for longer than either serum or urine amylase values. The findings of the study suggest that the amylase creatinine clearance ratio is a simple yet reliable diagnostic test which could be used when screening patients suspected of having acute pancreatitis. PMID:890263

  7. Beta 2-Microglobulin clearance as measured by radioimmunoassay

    Energy Technology Data Exchange (ETDEWEB)

    Woo, J.; Floyd, M.; Longley, M.A.; Cannon, D.C.

    1980-07-01

    We describe a radioimmunoassay for beta 2-microglobulin (beta 2 mu) in serum and urine. We incubated aliquots of diluted samples at room temperature for 1 h with /sup 125/I-labeled beta 2 mu and a rabbit antiserum monospecific for human beta 2 mu, and separated the phases by the double-antibody technique. The logit-log transformed dose-response curve was linear in the range 2 to 64 ng, equivalent to 0.5 to 16 mg/L of serum and 0.5 to 320 mg/L of urine. Assay sensitivity was 2.4 ng of beta 2 mu. Validation studies included tests of precision, accuracy, antibody specificity, and parallelism of the dose-response curves for standard and unknown. In a study of 25 normal individuals, serum and urine beta 2 mu ranged from 1.1 to 2.3 mg/L and 40 to 360 micrograms/24 h; the clearance of beta 2 mu was 8 to 130 microL/min. In 21 renal allograft recipients tested one to five weeks after transplantation, serum and urine beta 2 mu ranged from 3.9 to 15.6 mg/L and 7.2 to 611 mg/24 h; beta 2 mu clearance was 0.60 to 33.3 mL/min. Values for both serum and urine correlated well with severity of allograft rejection.

  8. Renal clearance of pancreatic and salivary amylase relative to creatinine in patients with chronic renal insufficiency.

    Science.gov (United States)

    Keogh, J B; McGeeney, K F; Drury, M I; Counihan, T B; O'Donnell, M D

    1978-12-01

    Pancreatic and salivary amylase/creatinine clearance ratios in patients with various degrees of renal impairment were compared with those obtained for control subjects. In chronic renal insufficiency (mean GFR 30 ml/min +/- 15 SD; n = 13) the clearance ratios for pancreatic (mean 3.5 +/- 1.85 SD) and salivary (mean 2.3 +/- 1.3 SD) amylase were significantly higher (P less than 0.05) than those in controls. Corresponding control values (n = 26) were 2.64 +/- 0.86 (pancreatic) and 1.64 +/- 0.95 (salivary). Three patients showed values above the normal limit. In the diabetic group (mean GFR 41 ml/min +/- 22 SD; n = 10) salivary amylase/creatinine clearance ratios (mean 2.36 +/- 1.55 SD) were significantly higher than in controls (P less than 0.05). Three patients showed raised values. Pancreatic amylase clearance was raised in only one of these patients. Three patients with terminal disease (mean GFR 10 ml/min) showed markedly raised (two- to threefold) clearance ratios for both salivary and pancreatic amylase. Of a total of 26 patients, eight had increased total amylase/creatinine clearance ratios. Pancreatic amylase/creatinine clearance was increased in seven patients, while nine patients showed raised salivary amylase/creatinine ratios. Patients with raised clearance ratios did not have clinical evidence of pancreatitis. We suggest that, in the presence of impaired renal function, a high amylase/creatinine clearance ratio need not be indicative of pancreatic disease.

  9. Clearance of glucose and sucrose from the saliva of human subjects.

    Science.gov (United States)

    Sreebny, L M; Chatterjee, R; Kleinberg, I

    1985-01-01

    The ability of 20 healthy people to clear test solutions of sucrose (0.73 M) and glucose (1.4 M) from the mouth was examined. Both sugars were cleared within 20 min in a two-step manner. Rapid clearance occurred between 0 and 6 min; much slower clearance occurred thereafter. It took 7.2 min with glucose and 6.3 min with sucrose for the saliva-sugar concentration to fall to 1 mg/ml. Salivary flow, stimulated during sugar exposure, decreased in a two-step pattern similar to sugar clearance. Evidently, clearance was dependent on the rate of flow of saliva which took about 1 h to return to its resting flow level. Comparison of the pattern of sugar clearance to the Stephan curve (the rapid pH fall followed by a slow pH rise seen after rinsing with sugar solutions) indicated that the pH-fall phase of the curve occurs during the initial period of rapid sugar clearance and salivary flow, and the pH-rise phase occurs during the subsequent period of slower clearance and slow saliva flow. Comparison with the data of Swenander-Lanke (1957) [Acta odont. scand. 15, 3-156], indicated that the clearance of sugar solutions also reflects the clearance of sugar-containing solid foods from the mouth. PMID:3857898

  10. Gamma-variate plasma clearance versus urinary plasma clearance of (51) Cr-EDTA in patients with cirrhosis with and without fluid retention

    DEFF Research Database (Denmark)

    Fuglsang, Stefan; Henriksen, Ulrik L; Hansen, Hanne B;

    2016-01-01

    In patients with fluid retention, the plasma clearance of (51) Cr-EDTA (Clexp obtained by multiexponential fit) may overestimate the glomerular filtration rate (GFR). The present study was undertaken to compare a gamma-variate plasma clearance (Clgv) with the urinary plasma clearance of (51) Cr...... the injected dose relative to the plasma concentration-time area, obtained by a gamma-variate iterative fit. Clexp and Clu were determined by standard technique. In patients without fluid retention, Clgv , Clexp and Clu were closely similar. The difference between Clgv and Clu (Clgv - Clu = ΔCl) was mean -0...

  11. Bronchoscintigraphy and pulmonary clearance of {sup 99{sup m}}Tc-albumin colloid in study of mucociliary clearance

    Energy Technology Data Exchange (ETDEWEB)

    Mortensen, Jann

    1998-12-31

    A radioaerosol based method for measuring MC was introduced. It included an inhalation protocol that resulted in a predominant deposition of radioaerosol in the central bronchi and two simple procedures of evaluation: 1) a visual semi-quantitative bronchoscintigraphic analysis, and 2) a quantitative analysis of the retention of the radioactivity at different points after the inhalation. The results showed that bronchoscintigraphy was a simple technique that may be used to visualize a stimulation of mucociliary transport in the central airways of individuals that do not suffer from too much mucus hypersecretion. Comparison of the MC between individuals, however, should preferably be performed by the method of quantitative analysis of the radioactivity disappearance. A change of MC was found to be one of the first detectable effects on lung function of tobacco smoking. It could be effectively detected by measurement of radioaerosol clearance both by bronchoscintigraphy and simple quantification of the MC. The MC may be either acutely enhanced, reduced or not changed by smoking. Long-term smoking impairs MC. The enhancement of MC by {beta}{sub 2}-agonists was very limited in most patients with CF. In the hope of increasing mucus transport in patients with CF, these are treated with various chest physiotherapy techniques. The radioaerosol based method of measurement of MC could assess mucus clearance by chest physiotherapy and cough. (au) 141 refs.

  12. Clearance of beta-2-microglobulin and middle molecules in haemodiafiltration.

    Science.gov (United States)

    Tattersall, James

    2007-01-01

    Middle molecules, consisting mostly of peptides and small proteins with molecular weight the range of 500-60,000 Da, accumulate in renal failure and contribute to the uraemic toxic state. Beta2-microglobulin (beta2-MG) with a molecular weight of 11,000 is considered representative of these middle molecules. These solutes are not well cleared by low-flux dialysis. High-flux dialysis will clear middle molecules, partly by internal filtration. This convective component of high-flux dialysis can be enhanced in a predictable way by haemodiafiltration (HDF). The convective and diffusive clearance rates of any middle molecule across any haemodiafilter can be predicted from known or measurable factors such as its sieving coefficient, bound fraction and molecular weight. The removal of middle molecules is also influenced by factors within the patient. Beta2-MG is distributed within the extracellular fluid. During HDF, beta2-MG must transfer into the intravascular compartment across the capillary walls. This transcapillary transfer at a rate of approximately 100 ml/min slows beta2-MG removal from the body. Continuing transfer after the end of a treatment session results in a significant rebound of beta2-MG levels. This intercompartment transfer and its effect on beta2-MG clearance and concentration can be predicted by a 2-compartment model. By extrapolation, the behaviour of other middle molecules can be predicted. The 2-compartment model, which takes non-dialytic beta2-MG clearance at a rate of 3 ml/min and beta2-MG generation at a rate of 0.1 mg/min into account, can predict the effect of any HDF schedule on beta2-MG levels. Low-flux dialysis results in a beta2-MG level of around 40 mg/l. Three times weekly, 4-hour HDF can reduce beta2-MG levels to around 20 mg/l. Long (nocturnal) HDF can reduce beta2-MG levels to around 10 mg/l, compared to physiological levels of less than 5 mg/l.

  13. Shape memory alloy adaptive control of gas turbine engine compressor blade tip clearance

    Science.gov (United States)

    Schetky, Lawrence M.; Steinetz, Bruce M.

    1998-06-01

    The ambient air ingested through the inlet of a gas turbine is first compressed by an axial compressor followed by further compression in a centrifugal compressor and then fed into the combustion chamber where ignition and expansion take place to produce the engine thrust. The axial compressor typically has five or more stages which consist of revolving blades and stators and the overall performance of the turbine is strongly affected by the compressor efficiency. When the turbine is turned on, to accommodate the rapid initial increase in the compressor blade length due to centrifugal force, the cold turbine has a built in clearance between the turbine blade tip and the casing. As the turbine reached its operating temperature there is a further increase in the blade length due to thermal expansion and, at the same time, the diameter of the casing increases. The net result is that when these various components have reached their equilibrium temperatures, the initial cold build clearance is reduced, but there remains a residual clearance. The magnitude of this clearance has a direct effect on the compressor efficiency and can be stated as: Δη/Δ CLR equals 0.5 where η is efficiency and CLR is the tip clearance. The concept of adaptive tip clearance control is based on the ability of a shape memory alloy ring to shrink to a predetermined diameter when heated to the temperature of a particular stage, and thus reducing the tip clearance. The ring is fabricated from a CuAlNi shape memory alloy and is mounted in the casing so as to be coaxial with the rotating blades of the particular stage. When cold, the ring dimensions are such as to provide the required cold build clearance, but when at operating temperature the reduced diameter creates a very small tip clearance. The clearance provided by this concept is much smaller than the clearance normally obtained for a turbine of the size being studied.

  14. NRPB volunteer study: deposition and clearance of inhaled particles

    International Nuclear Information System (INIS)

    At the Board Meeting of the National Radiological Protection Board held on 15 February 1996, approval was given for an experimental study of the deposition and clearance of inhaled particles in the human nasal passage. This is the latest in a series of volunteer biokinetic studies that have been conducted at NRPB since its formation. This article explains the purpose of the study, how ethical approval was obtained, how the study will be performed, what volunteers will be asked to do, and what doses they will receive. Doses will of course be carefully controlled, and will be well below the annual limits set for such experiments. The success of the study is of course crucially dependent on recruitment of a sufficient number of volunteers. The aim of this article is to provide information to anyone who might be interested in volunteering. (UK)

  15. Effect of lindane on the clearance rate of daphnia magna

    Science.gov (United States)

    Hartgers; Heugens; Deneer

    1999-05-01

    The impact of the insecticide lindane (gamma-hexachlorocyclohexane) on the clearance rate (CR) of Daphnia magna was investigated using artificial beads. CR (24-h EC50: 65 &mgr;g L-1) was found to be a more sensitive endpoint than acute lethality for D. magna (48-h LC50: 516 &mgr;g L-1). The onset of the effect was rapid; after 2 h of exposure to approximately 241 &mgr;g L-1 of lindane a significant decrease in CR was observed. Daphnids recovered rapidly after transfer to clean water; after 24 h of exposure to approximately 250 &mgr;g L-1 lindane, transfer into clean water resulted in recovery to 80% of control levels within 2 h and complete recovery within 24 h. PMID:10227859

  16. Biodistribution and clearance of instilled carbon nanotubes in rat lung

    Directory of Open Access Journals (Sweden)

    Rogerieux Françoise

    2008-12-01

    Full Text Available Abstract Background Constituted only by carbon atoms, CNT are hydrophobic and hardly detectable in biological tissues. These properties make biokinetics and toxicology studies more complex. Methods We propose here a method to investigate the biopersistence of CNT in organism, based on detection of nickel, a metal present in the MWCNT we investigated. Results and conclusion Our results in rats that received MWCNT by intratracheal instillation, reveal that MWCNT can be eliminated and do not significantly cross the pulmonary barrier but are still present in lungs 6 months after a unique instillation. MWCNT structure was also showed to be chemically modified and cleaved in the lung. These results provide the first data of CNT biopersistence and clearance at 6 months after respiratory administration.

  17. Dynamic analysis for planar beam with clearance joint

    Science.gov (United States)

    Yao, XiaoGuang; Guo, XiaoSong; Feng, YongBao; Yu, ChuanQiang; Ma, Changlin

    2015-03-01

    An analytical model was presented in this study to describe the dynamic characteristics of a planar rotation beam with clearance joint. The spherical contact model was introduced to calculate the collision forces for the planar revolute joint. Unlike previous research, to acquire an accurate and convergent solution, the second-order coupling term of the beam axial deformation is taken into account. Then, the flexible beam was divided into discrete elements via the finite element method. The dynamic equations of the model were deduced via the Hamilton's principle. Further, the dynamic responses were obtained and analyzed in the non-inertial and inertial coordinates. To prove the validity of the presented methodology, a virtual prototype model with identical conditions was created in ADAMS. A numerical example was simultaneously calculated by the two different approaches. Comparison of the results shows that the two approaches match quite well. Finally, some valuable conclusions describing the inner-joint collision process are extracted and summarized.

  18. Restoration of an endodontically treated premolar with limited interocclusal clearance

    Directory of Open Access Journals (Sweden)

    Sandya K Kini

    2013-01-01

    Full Text Available Endodontically treated teeth with the loss of coronal tooth structure when left untreated for a long period may cause supraeruption, drifting, tipping, and rotation of adjacent and opposing teeth. This may be challenging to the clinician, when fabricating a crown because of inadequate interocclusal space. This case report describes a simple technique to restore an endodontically treated maxillary first premolar with the loss of coronal tooth structure and lack of interocclusal space. The maxillary first premolar had a single root canal and was endodontically treated. The lower premolar had supraerupted reducing the interocclusal space. A minimally invasive and esthetic technique was used to restore the tooth with limited interocclusal clearance. The tooth was restored with a Richmond crown, which had the morphology of a canine instead of a premolar. Thus, the tooth was salvaged by changing the morphology of the crown and the desired functional and esthetic results were obtained.

  19. Clinical use of amylase clearance and isoamylase measurements.

    Science.gov (United States)

    Levitt, M D

    1979-07-01

    Isoamylase determinations and measurements of the ratio of the renal clearance of amylase relative to creatinine (CAm/CCr) were employed in an attempt to improve the diagnostic accuracy of the standard amylase measurement. An elevated CAm/CCr reflects defective proximal tubular reabsorption of amylase which occurs in virtually all patients with clear-cut acute pancreatitis. However, other conditions that apparently are associated with acute defective tubular function, such as burns and diabetic acidosis, may cause an elevated ratio. Thus, elevations of CAm/CCr cannot be considered to be specific for acute pancreatitis. Pancreatic isoamylase represents, on the average, about 33% of the normal serum amylase activity, whereas about 66% is salivary-type isoamylase. Isoamylase measurements are useful in determining whether an elevated value for serum amylase activity is of pancreatic origin. However, this measurement is not useful for determining whether patients with normal serum amylase activity have pancreatitis.

  20. Esophageal clearance scintigraphy in, diabetic patients; A preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Karayalcin, B.; Karayalcin, U.; Aburano, Tamio; Nakajima, Kenichi; Hisada, Kinichi; Morise, Toshio; Okada, Toshihide; Takeda, Ryoyu (Kanazawa Univ. (Japan). School of Medicine)

    1992-05-01

    The aim of this preliminary study was to evaluate the predictive value of esophageal clearance scintigraphy (ECS) in the diagnosis of esophageal autonomic neuropathy in diabetic patients without any esophageal symptoms. A single swallon ECS was performed in 12 diabetic patients and 15 normal volunteers, and esophageal transit time (ETT) and esophageal (Es) T 1/2 values were calculated. ETT and Es 1/2 were found to be significantly prolonged in the diabetic group (p<0.01 and p<0.05, respectively). In this preliminary study, our results strongly suggest that ECS may be an important noninvasive diagnostic tool in the evaluation of diabetic patients with asymptomatic esophageal autonomic neuropathy. (author).

  1. Estimate of clearance levels for metal materials contaminated with uranium

    International Nuclear Information System (INIS)

    Clearance levels for the solid materials contaminated with uranium were estimated based on deterministic dose calculation approach for metal reuse scenario. The activity concentrations for major radionuclides, U-234, U-235 and U-238, were calculated to be 1.5Bq/g, 1.4Bq/g and 1.8Bq/g, respectively. In order to confirm the validity of the calculated concentrations, the authors estimated the uncertainties on scenario description after metal recycling and on parameter values used in the deterministic calculation. The validity of the calculated activity concentrations by the deterministic approach was confirmed from the results of both the analysis for an additional scenario on the landfill disposal of residue of slag after metal recycling and the Monte Carlo-based analysis for parameter uncertainties. (author)

  2. Container scanning to reduce time of customs clearance process

    Directory of Open Access Journals (Sweden)

    Yuri da Cunha Ferreira,

    2015-12-01

    Full Text Available One way to increase customs clearance efficiency and to assure supply chain security is the use of non-intrusive inspection equipment, such as scanners. In Brazil, scanners are new, but their use at port terminals is growing rapidly. Considering the possibility of Brazilian Customs requesting 100% scanning of loads, this study aims to assess the operational impacts of this possible request at a specific port terminal. This is the originality of this research. To do so, this study uses applied simulation methods in a case study. Results show that for the current scenario, scanners do not appear to be an operational bottleneck at this port, but the scanning capacity will be exceeded with the planned port expansion. Hence, scheduling rules for single machines were applied to optimize scanning performance. These heuristics provided good performance, suggesting that scanners can provide benefits to priority cargo handling, and could eventually increase the performance of port terminals throughout the country.

  3. Renal Clearance: Using an Interactive Activity to Visualize a Tricky Concept

    Science.gov (United States)

    Hull, Kerry

    2016-01-01

    Renal clearance, the volume of blood cleared of a substance in a particular time period, is commonly recognized as one of the most difficult concepts in physiology. This difficulty may in part reflect the quantitative nature of renal clearance since many life sciences majors perceive that mathematics is irrelevant to their discipline. Students may…

  4. Development of a modular virus clearance package for anion exchange chromatography operated in weak partitioning mode.

    Science.gov (United States)

    Iskra, Timothy; Sacramo, Ashley; Gallo, Chris; Godavarti, Ranga; Chen, Shuang; Lute, Scott; Brorson, Kurt

    2015-01-01

    Anion exchange chromatography (AEX) operated under weak partitioning mode has been proven to be a powerful polishing step as well as a robust viral clearance step in Pfizer's monoclonal antibody (mAb) platform purification process. A multivariate design of experiment (DoE) study was conducted to understand the impact of operating parameters and feedstream impurity levels on viral clearance by weak partitioning mode AEX. Bacteriophage was used initially as a surrogate for neutral and acidic isoelectric point mammalian viruses (e.g., retrovirus and parvovirus). Five different mAbs were used in the evaluation of process parameters such as load challenge (both product and impurities), load pH, load conductivity, and contact time (bed height and flow-rate). The operating ranges obtained from phage clearance studies and Pfizer's historical data were used to define an appropriate operating range for a subsequent clearance study with model retrovirus and parvovirus. Both phage and virus clearance evaluations included feedstreams containing different levels of impurities such as high molecular mass species (HMMS), host cell proteins (HCPs), and host cell DNA. For all the conditions tested, over 5 log10 of clearance for both retrovirus and parvovirus was achieved. The results demonstrated that weak partitioning mode AEX chromatography is a robust step for viral clearance and has the potential to be included as part of the modular viral clearance approach.

  5. 49 CFR 236.73 - Open-wire transmission line; clearance to other circuits.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Open-wire transmission line; clearance to other... line; clearance to other circuits. Open-wire transmission line operating at voltage of 750 volts or... THE INSTALLATION, INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS,...

  6. Low serum hyaluronic acid levels associated with spontaneous HBsAg clearance

    NARCIS (Netherlands)

    Harkisoen, S.; Arends, J. E.; van den Hoek, A.; van Erpecum, K. J.; Boland, G. J.; Hoepelman, A. I. M.

    2015-01-01

    Purpose The pathophysiological underlying mechanism of spontaneous HBsAg clearance in hepatitis B virus (HBV) infected patients is largely unknown. However, serum hyaluronic acid (sHA) plays a role in liver fibrosis progression and reversely could serve as a potential biomarker for HBsAg clearance.

  7. Relationship of end-expiratory pressure, lung volume, and /sup 99m/Tc-DTPA clearance

    International Nuclear Information System (INIS)

    We investigated the dose-response effect of positive end-expiratory pressure (PEEP) and increased lung volume on the pulmonary clearance rate of aerosolized technetium-99m-labeled diethylenetriaminepentaacetic acid (99mTc-DTPA). Clearance of lung radioactivity was expressed as percent decrease per minute. Base-line clearance was measured while anesthetized sheep (n = 20) were ventilated with 0 cmH2O end-expiratory pressure. Clearance was remeasured during ventilation at 2.5, 5, 10, 15, or 20 cmH2O PEEP. Further studies showed stepwise increases in functional residual capacity (FRC) (P less than 0.05) measured at 0, 2.5, 5, 10, 15, and 20 cmH2O PEEP. At 2.5 cmH2O PEEP, the clearance rate was not different from that at base line (P less than 0.05), although FRC was increased from base line. Clearance rate increased progressively with increasing PEEP at 5, 10, and 15 cmH2O (P less than 0.05). Between 15 and 20 cmH2O PEEP, clearance rate was again unchanged, despite an increase in FRC. The pulmonary clearance of aerosolized /sup 99m/Tc-DTPA shows a sigmoidal response to increasing FRC and PEEP, having both threshold and maximal effects. This relationship is most consistent with the hypothesis that alveolar epithelial permeability is increased by lung inflation

  8. Influence of Renal Failure on Intestinal Clearance of Ciprofloxacin in Rats

    OpenAIRE

    Dautrey, Sophie; Rabbaa, Lydia; Laouari, Denise; Lacour, Bernard; Carbon, Claude; Farinotti, Robert

    1999-01-01

    Following intravenous doses, ciprofloxacin pharmacokinetics in control and nephrectomized rats were studied. There were no differences between control and nephrectomized rats for area under the concentration-time curve in plasma or biliary clearance. The intestinal clearance of ciprofloxacin was increased in nephrectomized rats. Intestinal elimination seems to compensate partially for the decrease in urinary excretion of ciprofloxacin in nephrectomized rats.

  9. Factors Associated with Spontaneous Clearance of Hepatitis C Virus in Chinese Population

    Directory of Open Access Journals (Sweden)

    Fei Kong

    2014-01-01

    Full Text Available Hepatitis C virus (HCV infections spontaneously clear in approximately 15–45% of infected individuals. Factors which influence spontaneous HCV clearance remain to be identified. The purpose of the present study was to identify variables associated with spontaneous HCV clearance in a referred population of Chinese patients. The prevalence of host, viral, and environmental factors known to influence the outcome of HCV infections was compared in 92 HCV spontaneous clearance subjects and 318 HCV persistent infection subjects. Univariate and multivariate analyses were performed to identify those factors associated with spontaneous HCV clearance. In univariate analysis, female gender, a history of icteric hepatitis, serologic evidence of concurrent HBV infection, and rs12979860 CC genotype were positively associated with spontaneous HCV clearance, while alcohol consumption was negatively associated with clearance. In multivariate analysis, female gender, a history of icteric hepatitis, concurrent HBV infection, and rs12979860 CC genotype remained independent variables associated with spontaneous HCV clearance. Spontaneous HCV clearance is more likely to occur in females, subjects with a history of icteric hepatitis, HBV coinfections, and those with the rs12979860 CC genotype.

  10. Effect of prior immobilization on muscular glucose clearance in resting and running rats

    International Nuclear Information System (INIS)

    In vitro studies have shown that prior disuse impairs the glucose clearance of red skeletal muscle because of a developed insensitivity to insulin. We studied whether an impaired glucose clearance is present in vivo in 42-h immobilized muscles of resting rats and, furthermore, whether the exercise-induced increase in glucose clearance of red muscles is affected by prior immobilization. The 2-[3H]deoxy-D-glucose (2DG) bolus injection method was used to determine glucose clearance of individual muscles. At rest, glucose clearance was markedly impaired in rats with previously immobilized red muscles compared with nonimmobilized control rats. During running, glucose clearance did not differ between muscles in previously immobilized and control rats. Insulin levels were always similar in the two groups and decreased during exercise. Intracellular nonphosphorylated 2DG was present in tissues with high glucose clearances. In conclusion, 42 h of immobilization markedly impairs glucose clearance of resting red muscle fibers in vivo. Apparently, physical inactivity in particular affects steps involved in insulin-mediated action that are not part of contraction-induced glucose uptake and metabolism. Presence of intracellular 2DG shows that separate determination of phosphorylated 2DG is necessary for accurate estimates of glucose metabolism and that accumulation of phosphorylated 2DG does not accurately reflect glucose transport

  11. Tube to U-bend support bar in-situ clearance measurement

    International Nuclear Information System (INIS)

    Most recirculating nuclear steam generators throughout the world have some type of flat bar U-bend restraint or anti-vibration bar for the purpose of positioning the long flexible U-bend tubes in their respective planes. These support bars minimize tube response to flow induced vibration forces and mitigate fretting of tubes due to those forces. Steam generators from all sources have experienced some degree of fretting, usually on a relatively small number of tubes. Flow induced vibration response and fretting are influenced by a large number of parameters including the flow velocity, density, the tube diameter and stiffness, the tube and bar material combination and also the magnitude and consistency of the tube to bar clearances. Over the years the nominal tube to bar support clearances have been systematically reduced. Nevertheless some fretting has still persisted. In pursuing the problem, the expectation is that the situation will be avoided by further reducing nominal clearance. On the other hand, there is little data in hand as to the actual local clearances or the distribution of clearances within a U-bend array. Therefore, it is not possible to ascertain from field data what clearance conditions are necessary for fretting to exist; or more importantly what clearance conditions are necessary to avoid fretting. This paper describes the development for eddy current inspection techniques for in-situ measurement of tube to U-bend support bar clearance. (author)

  12. 33 CFR 222.3 - Clearances for power and communication lines over reservoirs.

    Science.gov (United States)

    2010-07-01

    ... be provided when relocating existing or constructing new power and communication lines over waters of... section). (e) Required clearances. Minimum vertical clearances for power and communication lines over... communication lines over reservoirs. 222.3 Section 222.3 Navigation and Navigable Waters CORPS OF...

  13. Active generalized predictive control of turbine tip clearance for aero-engines

    Institute of Scientific and Technical Information of China (English)

    Peng Kai; Fan Ding; Yang Fan; Fu Qiang; Li Yong

    2013-01-01

    Active control of turbine blade tip clearance continues to be a concern in design and con-trol of gas turbines. Ever increasing demands for improved efficiency and higher operating temper-atures require more stringent tolerances on turbine tip clearance. In this paper, a turbine tip clearance control apparatus and a model of turbine tip clearance are proposed;an implicit active generalized predictive control (GPC), with auto-regressive (AR) error modification and fuzzy adjustment on control horizon, is presented, as well as a quantitative analysis method of robust per-turbation radius of the system. The active clearance control (ACC) of aero-engine turbine tip clear-ance is evaluated in a lapse-rate take-off transient, along with the comparative and quantitative analysis of the stability and robustness of the active tip clearance control system. The results show that the resultant active tip clearance control system with the improved GPC has favorable steady-state and dynamic performance and benefits of increased efficiency, reduced specific fuel consump-tion, and additional service life.

  14. Effect of adrenergic stimulation on clearance from small ciliated airways in healthy subjects.

    Science.gov (United States)

    Svartengren, K; Philipson, K; Svartengren, M; Camner, P

    1998-01-01

    Mucociliary transport is an important clearance mechanism of larger airways, but in the smallest ciliated airways (bronchioles) it may be less effective. The present study aimed at investigating whether clearance from the bronchioles in subjects with healthy airways was stimulated by an adrenergic agonist (terbutaline sulphate). Tracheobronchial clearance was studied twice in 10 healthy subjects after inhalation of 6-micron (aerodynamic diameter) monodisperse Teflon particles labeled with 111In. At one exposure, oral treatment with terbutaline sulphate, known to stimulate clearance in large airways, began immediately after inhalation of the particles. The other exposure was a control measurement. The particles were inhaled at an extremely slow flow, 0.05 L/s, which gave deposition mainly in the small ciliated airways (bronchioles). Lung retention was measured at 0, 24, 48, and 72 h. Clearance was significant every 24 h for both exposures (p terbutaline sulphate, the subjects' pulse rates tended to be higher, but clearance rates did not increase. We found, as expected, no significant correlation between lung retention and lung function in either exposure. This study shows that an adrenergic agonist does not significantly influence overall clearance from the bronchiolar region in healthy subjects. This suggests that mucociliary transport does not significantly contribute to clearance from the smallest ciliated airways. Other mechanisms may be more important for the transportation of mucus from these airways. PMID:9555573

  15. Effect of prior immobilization on muscular glucose clearance in resting and running rats

    DEFF Research Database (Denmark)

    Vissing, J; Ohkuwa, T; Ploug, Thorkil;

    1988-01-01

    In vitro studies have shown that prior disuse impairs the glucose clearance of red skeletal muscle because of a developed insensitivity to insulin. We studied whether an impaired glucose clearance is present in vivo in 42-h immobilized muscles of resting rats and, furthermore, whether the exercis...

  16. Regional alterations in long bone produced by internal fixation devices. Part I. 85Sr clearance

    International Nuclear Information System (INIS)

    We examined the effect of rigid plate application on the radiostrontium clearance of the intact canine femur at 6 months. We examined each of the component surgical steps. We calculated the clearance both for the whole bone and for each of the five transverse sections of the whole bone. Screw application, but not drilling, increased the clearance in the segment about the screw holes. Plate application produced an increase in the segment beneath the plate as well as around the screws and in the whole bone. These changes are accomplished not only by an absolute increase in clearance to the middle three segments, but by a relative diminution in clearance by the most proximal and distal segments. The histomorphometric changes in long bones following rigid plating may be accompanied by regional increases in bone blood flow

  17. Vest Chest Physiotherapy Airway Clearance is Associated with Nitric Oxide Metabolism

    Directory of Open Access Journals (Sweden)

    Joseph H. Sisson

    2013-01-01

    Full Text Available Background. Vest chest physiotherapy (VCPT enhances airway clearance in cystic fibrosis (CF by an unknown mechanism. Because cilia are sensitive to nitric oxide (NO, we hypothesized that VCPT enhances clearance by changing NO metabolism. Methods. Both normal subjects and stable CF subjects had pre- and post-VCPT airway clearance assessed using nasal saccharin transit time (NSTT followed by a collection of exhaled breath condensate (EBC analyzed for NO metabolites (. Results. VCPT shorted NSTT by 35% in normal and stable CF subjects with no difference observed between the groups. EBC concentrations decreased 68% in control subjects after VCPT (before = 115 ± 32 μM versus after = 37 ± 17 μM; . CF subjects had a trend toward lower EBC . Conclusion. We found an association between VCPT-stimulated clearance and exhaled levels in human subjects. We speculate that VCPT stimulates clearance via increased NO metabolism.

  18. Study on leakage flow characteristics of radial inflow turbines at rotor tip clearance

    Institute of Scientific and Technical Information of China (English)

    DENG QingHua; NIU JiuFang; FENG ZhenPing

    2008-01-01

    Tip clearance leakage flow in a radial inflow turbine rotor for microturbines under the stage environment is investigated using a three-dimensional viscous flow simulation. The results indicate that the scraping flow caused by relative motion between casing and rotor tip, and the pressure difference between pressure side and suction side at rotor tip, play important roles in tip clearance leakage flow. The more the rotor tip speed increases and tip clearance height decreases, the more the scraping effect acta. Though the leakage velocity of tip clearance at midsection and exducer regions changes less when the rotor rotational speed is changing, the distance between passage vortex and rotor suction side varies in evidence. Main leakage flow rate of tip clearance takes place at region of exducer tip and some seal configurations will be quite effective for cutting leakage flow if these configurations are arranged over midsection and exducer of the radial inflow rotor.

  19. Study on leakage flow characteristics of radial inflow turbines at rotor tip clearance

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Tip clearance leakage flow in a radial inflow turbine rotor for microturbines under the stage environment is investigated using a three-dimensional viscous flow simulation. The results indicate that the scraping flow caused by relative motion between casing and rotor tip, and the pressure difference between pressure side and suction side at rotor tip, play important roles in tip clearance leakage flow. The more the rotor tip speed increases and tip clearance height decreases, the more the scraping effect acts. Though the leakage velocity of tip clearance at midsection and exducer regions changes less when the rotor rotational speed is changing, the distance between passage vortex and rotor suction side varies in evidence. Main leakage flow rate of tip clearance takes place at region of exducer tip and some seal configurations will be quite effective for cutting leakage flow if these configurations are arranged over midsection and exducer of the radial inflow rotor.

  20. Factors contributing to delay in parasite clearance in uncomplicated falciparum malaria in children

    Directory of Open Access Journals (Sweden)

    Sijuade Abayomi

    2010-02-01

    Full Text Available Abstract Background Drug resistance in Plasmodium falciparum is common in many endemic and other settings but there is no clear recommendation on when to change therapy when there is delay in parasite clearance after initiation of therapy in African children. Methods The factors contributing to delay in parasite clearance, defined as a clearance time > 2 d, in falciparum malaria were characterized in 2,752 prospectively studied children treated with anti-malarial drugs between 1996 and 2008. Results 1,237 of 2,752 children (45% had delay in parasite clearance. Overall 211 children (17% with delay in clearance subsequently failed therapy and they constituted 72% of those who had drug failure, i.e., 211 of 291 children. The following were independent risk factors for delay in parasite clearance at enrolment: age less than or equal to 2 years (Adjusted odds ratio [AOR] = 2.13, 95% confidence interval [CI]1.44-3.15, P 50,000/ul (AOR = 2.21, 95% CI = 1.77-2.75, P 20000/μl a day after treatment began, were independent risk factors for delay in clearance. Non-artemisinin monotherapies were associated with delay in clearance and treatment failures, and in those treated with chloroquine or amodiaquine, with pfmdr 1/pfcrt mutants. Delay in clearance significantly increased gametocyte carriage (P Conclusion Delay in parasite clearance is multifactorial, is related to drug resistance and treatment failure in uncomplicated malaria and has implications for malaria control efforts in sub-Saharan Africa.

  1. Can toe-ground footwear margin alter swing-foot ground clearance?

    Science.gov (United States)

    Nagano, Hanatsu; Sparrow, W A; Begg, Rezaul K

    2015-07-01

    Falls are an important healthcare concern in the older population and tripping is the primary cause. Greater swing foot-ground clearance is functional for tripping prevention. Trips frequently occur due to the lowest part of the shoe contacting the walking surface. Shoe design effects on swing foot-ground clearance are, therefore, important considerations. When a shoe is placed on a flat surface, there usually is small vertical margin (VM) between the walking surface and the minimum toe point (MTP). The current study examined the effects of VM on swing foot-ground clearance at a critical gait cycle event, minimum foot clearance (MFC). 3D coordinates of the swing foot (i.e. MTP and heel) were obtained during the swing phase. MTP represented the swing foot-ground clearance and various MTPs were modelled based on a range of VMs. The sagittal orientation of the toe and heel relative to the walking surface was also considered to evaluate effects of VM and swing foot angle on foot-ground clearance. Greater VM increased the swing foot-ground clearance. At MFC, for example, 0.09 cm increase was estimated for every 0.1cm VM. Foot angle throughout the swing phase was typically -30° and 70°. Increasing swing ankle dorsiflexion can maximise VM, which is effective for tripping prevention. Further research will be needed to determine the maximum thresholds of VM to be safely incorporated into a shoe.

  2. Effect of clearance on cartilage tribology in hip hemi-arthroplasty.

    Science.gov (United States)

    Lizhang, Jia; Taylor, Simon D; Jin, Zhongmin; Fisher, John; Williams, Sophie

    2013-12-01

    Hemi-arthroplasty of the hip (an artificial femoral head articulating against the natural acetabulum) is used to treat fractured necks of femur; however, there is evidence that articulation causes erosion of the cartilage, resulting in pain for the patient. Parameters that may influence this cartilage erosion include head material and roughness, clearance between the head and acetabulum and activity levels of the patient. This study has assessed the effect of clearance of hemi-arthroplasty articulations on the contact stress, friction and cartilage deformation in an in vitro tribological simulation of the hemi-arthroplasty joint that applied dynamic loads and motion. It has been demonstrated that peak contact stress increased from 5.6 to 10.6 MPa as radial clearance increased from small (1.8 mm). In all samples, friction factor increased with time and was significantly less with extra-large clearances compared to small (<0.6 mm), medium (0.6-1.2 mm) and large (1.2-1.8 mm) clearances. The cartilage deformation observed was significantly greater in acetabulum samples paired to give small or extra-large clearances compared to those with medium or large clearances.

  3. Numerical Investigation of Pressure Fluctuation Characteristics in a Centrifugal Pump with Variable Axial Clearance

    Directory of Open Access Journals (Sweden)

    Lei Cao

    2016-01-01

    Full Text Available Clearance flows in the sidewall gaps of centrifugal pumps are unsteady as well as main flows in the volute casing and impeller, which may cause vibration and noise, and the corresponding pressure fluctuations are related to the axial clearance size. In this paper, unsteady numerical simulations were conducted to predict the unsteady flows within the entire flow passage of a centrifugal pump operating in the design condition. Pressure fluctuation characteristics in the volute casing, impeller, and sidewall gaps were investigated with three axial clearance sizes. Results show that an axial clearance variation affects the pressure fluctuation characteristics in each flow domain by different degree. The greatest pressure fluctuation occurs at the blade pressure surface and is almost not influenced by the axial clearance variation which has a certainly effect on the pressure fluctuation characteristics around the tongue. The maximum pressure fluctuation amplitude in the sidewall gaps is larger than that in the volute casing, and different spectrum characteristics show up in the three models due to the interaction between the clearance flow and the main flow as well as the rotor-stator interaction. Therefore, clearance flow should be taken into consideration in the hydraulic design of centrifugal pumps.

  4. Modelling of Outer and Inner Film Oil Pressure for Floating Ring Bearing Clearance in Turbochargers

    Science.gov (United States)

    Zhang, Hao; Shi, Zhanqun; Gu, Fengshou; Ball, Andrew

    2011-07-01

    Floating ring bearing is widely used in turbochargers to undertake the extreme condition of high rotating speed and high operating temperature. It is also the most concerned by the designers and users alike due to its high failure rate and high maintenance cost. Any little clearance change may result in oil leakage, which in turn cause blue smoke or black smoke according to leakage types. However, there is no condition monitoring of this bearing because it is almost impossible to measure the clearance especially the inner clearance, in which the inner oil film directly bears the high speed rotation. In stead of measuring clearance directly, this paper has proposed a method that uses film pressure as a measure to monitor the bearing clearance and its variation. A non-linear mathematical model is developed by using Reynolds equations with non-linear oil film pressure. A full description of the outer and inner film is provided along both axial and radial directions. A numerical simulation is immediately carried out. Variable clearance changes are investigated using the mathematical model. Results show the relationship between clearance and film pressure.

  5. Effect of glucagon infusion on the renal clearance of amylase relative to creatinine.

    Science.gov (United States)

    Tedesco, F J; Davila, E; Gardner, L B

    1978-10-01

    Recent data seem to support a tubular defect as the mechanism of the elevated renal clearance of amylase relative to creatinine in acute pancreatitis. Glucagon has been proposed by some to be an important factor in this phenomenon. To examine the role of glucagon as this "tubular dysfunction factor", we investigated the effect of intravenously infused glucagon on the fractional excretion of amylase and the tubular handling of a low molecular weight protein, beta2 microglobulin, in normal, healthy volunteers. At glucagon levels far in excess of those seen in pancreatitis, the clearance ratio of beta2 microglobulin relative to creatinine increased, whereas the clearance ratio of amylase relative to creatinine did not increase above the normal range. The dissociation between beta2 microglobulin clearance and amylase clearance allows one to question the theory that tubular dysfunction is the mechanism of the elevated renal clearance of amylase relative to creatinine in acute pancreatitis. Glucagon does not appear to be the sole factor responsible for the elevation of renal clearance of amylase relative to creatinine in acute pancreatitis.

  6. Clinical application of plasma clearance of iohexol on feline patients.

    Science.gov (United States)

    Miyamoto, K

    2001-09-01

    Glomerular filtration rate (GFR) was estimated by plasma clearance of iohexol (PCio) in 52 conscious cats presented for a variety of reasons to Angel Animal Hospital over a 2-year period. Cats were divided into four groups according to their clinical conditions and reasons for measuring PCio. The median PCio (ml/min/kg) was 3.68 in normal cats (NM), 2.39 in cats with suspected renal disease (SP), 1.35 in cats referred to confirm renal dysfunction (RD), and 0.84 in cats with apparent clinical signs of renal failure (RF). There was a significant difference between the results for each group. The respective medians of blood urea nitrogen (BUN) and plasma creatinine concentration (Pcr) (mg/dl) were 15 and 1.40 in NM cats, 21 and 1.71 in SP cats, 30 and 2.20 in RD cats, and 48 and 3.30 in RF cats. The reference values of BUN and Pcr were 21 +/- 7 mg/dl and 1.5 +/- 0.4 mg/dl (mean +/- SD). Diminished renal function could not be detected in SP cats by either BUN or Pcr, while a marked decrease of GFR was demonstrated before BUN and Pcr increased, indicating the insensitivity of BUN and Pcr in detecting renal dysfunction in cats. PCio can be performed non-invasively in conscious cats, which improves the veterinarian's ability to detect early stages of chronic renal disease. PMID:11876631

  7. A Microwave Blade Tip Clearance Sensor for Propulsion Health Monitoring

    Science.gov (United States)

    Woike, Mark R.; Abdul-Aziz, Ali; Bencic, Timothy J.

    2010-01-01

    Microwave sensor technology is being investigated by the NASA Glenn Research Center as a means of making non-contact structural health measurements in the hot sections of gas turbine engines. This type of sensor technology is beneficial in that it is accurate, it has the ability to operate at extremely high temperatures, and is unaffected by contaminants that are present in turbine engines. It is specifically being targeted for use in the High Pressure Turbine (HPT) and High Pressure Compressor (HPC) sections to monitor the structural health of the rotating components. It is intended to use blade tip clearance to monitor blade growth and wear and blade tip timing to monitor blade vibration and deflection. The use of microwave sensors for this application is an emerging concept. Techniques on their use and calibration needed to be developed. As a means of better understanding the issues associated with the microwave sensors, a series of experiments have been conducted to evaluate their performance for aero engine applications. This paper presents the results of these experiments.

  8. Environmental studies and clearance compliance of Kudankulam Atomic Power Project

    International Nuclear Information System (INIS)

    Full text: Nuclear industry has played a leading role in evolving proper and effective environmental management impact from development practices right form inception thus minimizing the environmental impact from developmental activities of man. In the engineering design of nuclear power plant, safety is further enhanced considerably by providing double back-upped engineered safety systems. Besides the engineered safety, the other factors considered for ensuring environmental impact minimization are siting criteria, conservative rad-waste management, effluent treatment, application of stringent environmental protection standards for limiting waste discharges, an elaborate environmental surveillance program and an on site and off site emergency preparedness plan. Recently, nuclear power industry has taken a drive to develop and implement Environmental Management System (EMS) to all its operating stations in line with ISO-14001 standards. For Kudankulam atomic power project, a number of studies specifically for environmental protection are carried out to meet the requirements of Russian Federation, new guidelines of Ministry of environment and Forests (MOEF) and Atomic Energy Regulatory Board (AERB). In the present paper an attempt has been made to present the environmental management plan and clearance compliance status of the project

  9. Rate of clearance of intrathecal iopamidol in the dog.

    Science.gov (United States)

    Wilcox, J; Evill, C A; Sage, M R

    1986-01-01

    The incidence of post-myelographic side-effects has been significantly reduced since the advent of the new generation of water-soluble, non-ionic, contrast media (CM). One of these CM, iopamidol, has recently been released for clinical intrathecal use in Australia. Clinical evaluations have shown iopamidol to give excellent diagnostic results. However, many adverse side-effects have been cited in the literature. Reactions to iopamidol following myelography are thought to be due to the lack of a physiologic barrier between the extracellular fluid of the brain parenchyma and the CSF, thereby allowing CM to penetrate the brain parenchyma tissue, following subarachnoid injection. This study investigates the rate of clearance of intrathecal iopamidol from the brain in dogs by performing coronal CT scans at intervals over a 48 h, post-injection period. Analysis of similar regions of interest (ROI) for each time period indicate that iopamidol can be detected in canine brains for at least 48 h following intrathecal injection (P less than 0.05). Furthermore, the disappearance of iopamidol from the brain parenchyma is approximately logarithmic in form, with a half-life of approximately 22 h.

  10. Interspecies comparison of lung clearance using monodisperse terbium oxide particles

    International Nuclear Information System (INIS)

    Preliminary results are reported of measurements on human subjects, monkeys, dogs and rats following inhalation of 1.0 μm monodisperse 160Tb-labelled terbium oxide particles. Lung retention at 6 months ranged from about 0.1 of the initial alveolar deposit (IAD) in man, monkey and dog to 0.03 in rats. Most of 160Tb cleared from the lungs was dissolved and absorbed by blood and accumulated at systemic sites, with skeleton, and to a lesser extent liver, being shown as the principal organs of accumulation in the animal species. Neglecting fast particle clearance into faeces during the first days after inhalation, 160Tb was mainly excreted and accumulated in the urine (0.1 IAD). The results from this study, with metabolic data obtained from intravenously injected terbium, will be used with recently developed biokinetic models to derive the kinetics of absorption from the lungs to blood of these particles and the particle transport to the GI tract for each species. The biokinetics of each of the animal species will be compared with those determined for the human. (author)

  11. The amylase-creatinine clearance ratio following cardiopulmonary bypass.

    Science.gov (United States)

    Murray, W R; Mittra, S; Mittra, D; Roberts, L B; Taylor, K M

    1981-08-01

    The incidence of unexplained pancreatitis in patients dying after cardiac operations has been recorded as 16%, with evidence to implicate ischemia in the pathogenesis of the pancreatitis. Increased amylase--to--creatinine clearance ratios (ACCR), suggesting pancreatic dysfunction, have been reported in patients following nonpulsatile cardiopulmonary bypass (CPB). Pulsatile CPB is increasingly recognized to be a more physiological form of perfusion, particularly with respect to capillary blood flow. In this study the ACCR has been determined before, during, and after cardiac operations performed with both nonpulsatile and pulsatile CPB. Twenty patients undergoing elective cardiac operations were studied. Ten patients had nonpulsatile CPB (nonpulsatile group) and 10 had pulsatile CPB (pulsatile group). The two groups were comparable as regards perioperative variables and perfusion parameters. In both groups the ACCR was estimated preoperatively, on three occasions during the operation, and daily on the first 5 postoperative days. A significant elevation in ACCR was observed in nine of 10 patients in the nonpulsatile group but in only one of 10 patients in the pulsatile group (p less than 0.001). The significant improvement of ACCR stability following pulsatile CPB may indicate that this form of perfusion will reduce the risk of pancreatitis following cardiac operations performed with CPB.

  12. The amylase-creatinine clearance ratio following cardiopulmonary bypass.

    Science.gov (United States)

    Murray, W R; Mittra, S; Mittra, D; Roberts, L B; Taylor, K M

    1981-08-01

    The incidence of unexplained pancreatitis in patients dying after cardiac operations has been recorded as 16%, with evidence to implicate ischemia in the pathogenesis of the pancreatitis. Increased amylase--to--creatinine clearance ratios (ACCR), suggesting pancreatic dysfunction, have been reported in patients following nonpulsatile cardiopulmonary bypass (CPB). Pulsatile CPB is increasingly recognized to be a more physiological form of perfusion, particularly with respect to capillary blood flow. In this study the ACCR has been determined before, during, and after cardiac operations performed with both nonpulsatile and pulsatile CPB. Twenty patients undergoing elective cardiac operations were studied. Ten patients had nonpulsatile CPB (nonpulsatile group) and 10 had pulsatile CPB (pulsatile group). The two groups were comparable as regards perioperative variables and perfusion parameters. In both groups the ACCR was estimated preoperatively, on three occasions during the operation, and daily on the first 5 postoperative days. A significant elevation in ACCR was observed in nine of 10 patients in the nonpulsatile group but in only one of 10 patients in the pulsatile group (p less than 0.001). The significant improvement of ACCR stability following pulsatile CPB may indicate that this form of perfusion will reduce the risk of pancreatitis following cardiac operations performed with CPB. PMID:6166815

  13. Highly Catalytic Nanodots with Renal Clearance for Radiation Protection

    CERN Document Server

    Zhang, Xiao-Dong; Wang, Junying; Yang, Jiang; Chen, Jie; Shen, Xiu; Deng, Jiao; Deng, Dehui; Long, Wei; Sun, Yuan-Ming; Liu, Changlong; Li, Meixian

    2016-01-01

    Ionizing radiation (gamma and x-ray) is widely used in industry and medicine, but it can also pose a significant hazardous effect on health and induce cancer, physical deformity and even death, due to DNA damages and invasion of free radicals. There is therefore an urgent unmet demand in designing highly efficient radioprotectants with synergetic integration of effective renal clearance and low toxicity. In this study, we designed ultrasmall (sub-5 nm) highly catalytically active and cysteine-protected MoS2 dots as radioprotectants and investigated their application in protection against ionizing radiation. In vivo preclinical studies showed that the surviving fraction of MoS2-treated mice can appreciably increase to up to 79 % when they were exposed to high-energy ionizing radiation. Furthermore, MoS2 dots can contribute in cleaning up the accumulated free radicals within the body, repairing DNA damages and recovering all vital chemical and biochemical indicators, suggesting their unique role as free radical...

  14. The kidneys play an important role in the clearance of rFVIIa in rats

    DEFF Research Database (Denmark)

    Vestergaard, Bill; Appa, Rupa S.; Lykkesfeldt, Jens;

    2014-01-01

    INTRODUCTION: Previous distribution and histological studies have indicated that the kidneys and renal proximal tubular cells play a role in clearance of rFVIIa. However, the relative importance of the kidneys in clearance of rFVIIa has not previously been addressed. The objective of the present...... study was to evaluate the importance of the kidneys in the clearance process of rFVIIa after iv administration to rats using a nephrectomy model. MATERIALS AND METHODS: A nephrectomized rat model was established and validated using inulin, a compound primarily cleared by the kidneys, as a test substance...

  15. Pressure losses and flow field distortion induced by tip clearance of centrifugal and axial compressors

    Science.gov (United States)

    Senoo, Yasutoshi

    1987-03-01

    The flow field near the tip of compressor rotor blades is distorted by leakage through the tip clearance and the performance of the compressor is deteriorated. The literature regarding the tip clearance of compressor blades consists of computational fluid mechanics and experimental studies on the flow field and the pressure loss. Empirical equations expressing the pressure loss and the efficiency drop are varied. They relate to the lift coefficient in different ways, depending upon the ways of understanding the mechanics of pressure losses. These methods are examined and compared. Also, a brief discussion is made on the optimum value of the tip clearance.

  16. Limitation of amylase creatinine clearance ratio as a diagnostic test for postoperative pancreatitis.

    Science.gov (United States)

    Wapnick, S; Evans, M I; Hadas, N; Grosberg, S J

    1980-05-01

    The mean +/- S.E.M. ratio of amylase to creatinine clearance significantly increased at 24 hours after operations on the stomach and gallbladder but not after operations at sites remote from the abdominal cavity. Clinically, the elevated amylase to creatinine clearance ratio was not accompanied by pancreatitis. In dogs, surgical handling of the pancreas alone caused a significant increase in this measurement. The amylase to creatinine clearance ratio is not likely to be helpful in predicting the rare, but serious, postoperative complication of pancreatitis.

  17. Pressure loss due to the tip clearance of impellar blades in centrifugal and axial blowers

    Science.gov (United States)

    Senoo, Y.

    Equations to evaluate pressure loss based on the tip clearance of impeller blades (pressure loss induced by the leakage flow through the clearance, and pressure loss for supporting fluid against the pressure gradient in the thin annular clearance space between the shroud and the impeller) are derived. The predicted pressure losses are compared with experimental data for two types of centrifugal impellers. The equations are simplified for axial impellers as a special case, and the predicted efficiency-drop is compared with the experimental data for seven cases. Good agreement is demonstrated.

  18. Inhaled adrenergics and anticholinergics in obstructive lung disease: do they enhance mucociliary clearance?

    Science.gov (United States)

    Restrepo, Ruben D

    2007-09-01

    Pulmonary mucociliary clearance is an essential defense mechanism against bacteria and particulate matter. Mucociliary dysfunction is an important feature of obstructive lung diseases such as chronic obstructive pulmonary disease, asthma, cystic fibrosis, and bronchiectasis. This dysfunction in airway clearance is associated with accelerated loss of lung function in patients with obstructive lung disease. The involvement of the cholinergic and adrenergic neural pathways in the pathophysiology of mucus hypersecretion suggests the potential therapeutic role of bronchodilators as mucoactive agents. Although anticholinergics and adrenergic agonist bronchodilators have been routinely used, alone or in combination, to enhance mucociliary clearance in patients with obstructive lung disease, the existing evidence does not consistently show clinical effectiveness.

  19. Sulfadoxine-pyrimethamine monotherapy in Tanzanian children gives rapid parasite clearance but slow fever clearance that is improved by chloroquine in combination therapy

    DEFF Research Database (Denmark)

    Tarimo, D S; Minjas, J N; Bygbjerg, I C

    2002-01-01

    paracetamol (PCM) (n=38) in children with uncomplicated malaria. Over 72 h, there were eight (20.5%) treatment failures in the CQ group but none in the other groups. Although not significant (P > 0.1), irrespective of resistance CQ alone had a shorter median survival time to fever clearance than SP alone (54......Following widespread chloroquine (CQ) resistance, sulfadoxine plus pyrimethamine (SP) is now the first line antimalarial drug in a number of African countries including Tanzania. Unlike CQ, SP has no antipyretic effects, a feature that might delay fever clearance, and by acting on late stage...... vs. 60 h). SP plus CQ had a highly significantly shorter median survival time to fever clearance than SP alone (48 vs. 60 h) (P

  20. Total plasma clearance versus urinary plasma clearance of (51)Cr-EDTA in patients with cirrhosis with and without fluid retention

    DEFF Research Database (Denmark)

    Henriksen, Ulrik Lütken; Hansen, Hanne B; Ring-Larsen, Helmer;

    2015-01-01

    Abstract Background and aim. In patients with fluid retention, the total plasma clearance of (51)Cr-EDTA (ClP) may overestimate the glomerular filtration rate (GFR). The present study was therefore undertaken in order to compare ClP with the urinary plasma clearance of (51)Cr-EDTA (ClU) in patients...... with cirrhosis with and without fluid retention. Material and methods. A total of 136 patients with cirrhosis (24 without fluid retention, 112 with ascites) received a quantitative intravenous injection of (51)Cr-EDTA followed by plasma and quantitative urinary samples for 5 hours. ClP was determined from...

  1. Replication and clearance of respiratory syncytial virus - Apoptosis is an important pathway of virus clearance after experimental infection with bovine respiratory syncytial virus

    DEFF Research Database (Denmark)

    Viuff, B.; Tjørnehøj, Kirsten; Larsen, Lars Erik;

    2002-01-01

    and clearance in a natural target animal. Replication of BRSV was demonstrated in the luminal part of the respiratory epithelial cells and replication in the upper respiratory tract preceded the replication in the lower respiratory tract. Virus excreted to the lumen of the respiratory tract was cleared...... by neutrophils whereas apoptosis was an important way of clearance of BRSV-infected epithelial cells. Neighboring cells, which probably were epithelial cells, phagocytized the BRSV-infected apoptotic cells. The number of both CD4+ and CD8+ T cells increased during the course of infection, but the T cells were...

  2. Esophageal Acid Clearance Is Faster in Patients with Barrett's Esophagus Than in Healthy Controls During Random Swallowing

    DEFF Research Database (Denmark)

    Lottrup, Christian; Krarup, Anne Petas Swane; Gregersen, Hans;

    2016-01-01

    Background/Aims: Impaired esophageal acid clearance may be a contributing factor in the pathogenesis of Barrett's esophagus. However, few studies have measured acid clearance as such in these patients. In this explorative, cross-sectional study, we aimed to compare esophageal acid clearance...... and swallowing rate in patients with Barrett's esophagus to that in healthy controls. Methods: A total of 26 patients with histology-confirmed Barrett's esophagus and 12 healthy controls underwent (1) upper endoscopy, (2) an acid clearance test using a pH-impedance probe under controlled conditions including...... clearance test were not correlated (all P > 0.3). Conclusions: More frequent swallowing and thus faster acid clearance in Barrett's esophagus may constitute a protective reflex due to impaired mucosal integrity and possibly acid hypersensitivity. Despite these reinforced mechanisms, acid clearance ability...

  3. Traffic Incident Clearance Time and Arrival Time Prediction Based on Hazard Models

    Directory of Open Access Journals (Sweden)

    Yang beibei Ji

    2014-01-01

    Full Text Available Accurate prediction of incident duration is not only important information of Traffic Incident Management System, but also an effective input for travel time prediction. In this paper, the hazard based prediction models are developed for both incident clearance time and arrival time. The data are obtained from the Queensland Department of Transport and Main Roads’ STREAMS Incident Management System (SIMS for one year ending in November 2010. The best fitting distributions are drawn for both clearance and arrival time for 3 types of incident: crash, stationary vehicle, and hazard. The results show that Gamma, Log-logistic, and Weibull are the best fit for crash, stationary vehicle, and hazard incident, respectively. The obvious impact factors are given for crash clearance time and arrival time. The quantitative influences for crash and hazard incident are presented for both clearance and arrival. The model accuracy is analyzed at the end.

  4. NONLINEAR STABILITY OF BALANCED ROTOR DUE TO EFFECT OF BALL BEARING INTERNAL CLEARANCE

    Institute of Scientific and Technical Information of China (English)

    BAI Chang-qing; XU Qing-yu; ZHANG Xiao-long

    2006-01-01

    Stability and dynamic characteristics of a ball bearing-rotor system are investigated under the effect of the clearance in the ball bearing. Different clearance values are assumed to calculate the nonlinear stability of periodic solution with the aid of the Floquet theory. Bifurcation and chaos behavior are analyzed with variation of the clearance and rotational speed. It is found that there are three routes to unstable periodic solution.The period-doubling bifurcation and the secondary Hopf bifurcation are two usual routes to instability. The third route is the boundary crisis, a chaotic attractor occurs suddenly as the speed passes through its critical value. At last, the instable ranges for different internal clearance values are described. It is useful to investigate the stability property of ball bearing rotor system.

  5. Dynamics Research of rigid-flexible model of crank-rocker mechanism with Multi Clearance

    Directory of Open Access Journals (Sweden)

    Bo Shao Jun

    2016-01-01

    Full Text Available This paper takes the crank-rocker mechanism as the research object, purposed for the simulation of the motion pair with clearance utilizing the contact force model and the coulomb friction model, we build the virtual prototype of four-bar mechanism with clearance joints in the ADAMS. The article mainly contrasts the influence dynamics characteristics towards the mechanism multi-joint clearance between the rigid rocker and the flexible rocker. Considering the jointed arm’s flexibility, the four, five and six order modal of the rocker, generated by ANSYS as a neutral document, were imported into ADAMS for simulation. The result shows that Mechanism with four joint clearance increased the impact on the speed and the acceleration appeared greater fluctuation, the flexible rod has a buffer effect to the contact-impact forces, and the dynamic characteristics of fluctuations are improved.

  6. Intra-operative colloid administration increases the clearance of a post-operative fluid load

    DEFF Research Database (Denmark)

    Borup, Tine; Hahn, Robert; Holte, K;

    2009-01-01

    BACKGROUND: It is unknown whether an intra-operative colloid infusion alters the dynamics of a crystalloid load administered post-operatively. METHODS: Ten patients received 12.5 ml/kg of Ringer's lactate over 30 min 1-3 days before and 4 h after laparoscopic cholecystectomy, during which 10 ml....../kg of a colloid solution, hydroxyethylstarch (HES 130/0.4), was infused. The total body clearance of the pre- and post-operative test infusions was taken as the ratio between the urinary excretion and the Hb-derived dilution of venous plasma over 150 min. The plasma clearance of the infused fluid was calculated...... using volume kinetics based on the plasma dilution alone. The pre-operative plasma clearance was compared with the post-operative plasma clearance and patients served as their own control. RESULTS: The urinary excretion averaged 350 ml for the pre-operative infusion and 612 ml post-operatively, which...

  7. NUMERICAL SIMULATIONS FOR THE CASE OF RIGID ROTATING KINEMATIC COUPLING WITH BIG CLEARANCE

    Directory of Open Access Journals (Sweden)

    Jan-Cristian GRIGORE

    2010-10-01

    Full Text Available In this paper an algorithm based on [1] [2] are numerical simulations, achieving generalized coordinates of motion, positions, speeds of a rigid rotating kinematic coupling with big clearance in joint, case without friction

  8. 14 CFR 91.123 - Compliance with ATC clearances and instructions.

    Science.gov (United States)

    2010-01-01

    ... obtained, an emergency exists, or the deviation is in response to a traffic alert and collision avoidance... avoidance system resolution advisory, deviates from an ATC clearance or instruction shall notify ATC of...

  9. 78 FR 23627 - Agency Information Collection Activities: Requests for Comments; Clearance of Renewed Approval of...

    Science.gov (United States)

    2013-04-19

    ... aircraft and administer the leasing of the aircraft among the owners. DATES: Written comments should be... Collection Clearance Officer, IT Enterprises Business Services Division, AES-200. BILLING CODE 4910-13-P...

  10. Tramadol and o-desmethyl tramadol clearance maturation and disposition in humans

    DEFF Research Database (Denmark)

    Allegaert, Karel; Holford, Nick; Anderson, Brian J;

    2015-01-01

    BACKGROUND AND OBJECTIVES: We aimed to study the impact of size, maturation and cytochrome P450 2D6 (CYP2D6) genotype activity score as predictors of intravenous tramadol disposition. METHODS: Tramadol and O-desmethyl tramadol (M1) observations in 295 human subjects (postmenstrual age 25 weeks...... to 84.8 years, weight 0.5-186 kg) were pooled. A population pharmacokinetic analysis was performed using a two-compartment model for tramadol and two additional M1 compartments. Covariate analysis included weight, age, sex, disease characteristics (healthy subject or patient) and CYP2D6 genotype...... activity. A sigmoid maturation model was used to describe age-related changes in tramadol clearance (CLPO), M1 formation clearance (CLPM) and M1 elimination clearance (CLMO). A phenotype-based mixture model was used to identify CLPM polymorphism. RESULTS: Differences in clearances were largely accounted...

  11. 77 FR 30318 - Agency Information Collection Activities: 30-Day Notice of Intention To Request Clearance of...

    Science.gov (United States)

    2012-05-22

    ... From the Federal Register Online via the Government Publishing Office ] DEPARTMENT OF THE INTERIOR National Park Service Agency Information Collection Activities: 30-Day Notice of Intention To Request Clearance of Collection of Information; Opportunity for Public Comment AGENCY: National Park...

  12. 77 FR 50157 - Agency Information Collection Activities: 30-Day Notice of Intention To Request Clearance of...

    Science.gov (United States)

    2012-08-20

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE INTERIOR National Park Service Agency Information Collection Activities: 30-Day Notice of Intention To Request Clearance of Collection of Information; Opportunity for Public Comment AGENCY: National Park...

  13. Sensitivity of the amylase-creatinine clearance ratio in acute pancreatitis.

    Science.gov (United States)

    Farrar, W H; Calkins, G

    1978-06-01

    An elevated amylase-creatinine clearance ratio has been established as being highly specific for the diagnosis of acute pancreatitis. In the present study, the sensitivity of this test was compared to that of the serum amylase and the one-hour urinary amylase test in 29 patients with acute pancreatitis. Abnormal elevations of the amylase-creatinine clearance ratio were found less frequently than abnormal elevations of the serum and one-hour urinary amylases. Moreover, abnormal elevations of the amylase-creatinine clearance ratio showed less deviation from normal and values returned to normal sooner than those of the serum and one-hour urinary amylases. When compared to the serum amylase and the one-hour urinary amylase tests, the amylase-creatinine clearance ratio is a relatively insensitive test in patients with acute pancreatitis.

  14. Amylase-creatinine clearance ratios and serum amylase isoenzymes in moderate renal insufficiency.

    Science.gov (United States)

    Banks, P A; Sidi, S; Gelman, M L; Lee, K H; Warshaw, A L

    1979-12-01

    Both the amylase-creatinine clearance ratio (normal 1.55%) and proportion of pancreatic isoamylase in serum (normal 41.0%) increase in acute pancreatitis, and are therefore useful measurements to support that diagnosis. Whether renal insufficiency interferes with the accuracy and specificity of these tests has been debated. Our study indicates that even moderate renal insufficiency (creatinine clearance 30.5 ml/minute) raises the amylase-creatinine clearance ratio (3.23%) close enough to values characteristic of acute pancreatitis (4.41%) to cause potential diagnostic confusion. The fraction of pancreatic isoamylase in serum is also increased (69.9%), but not to the levels of acute pancreatitis (91.0%). We therefore caution against the use of the amylase-creatinine clearance ratio for the diagnosis of acute pancreatitis in patients with moderate renal insufficiency.

  15. Optical Method for Real-Time Turbine Blade Tip Clearance Measurement Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Monitoring and controlling blade tip clearance of high pressure turbines are important for maintaining the integrity of the engine during its operating points and...

  16. Proficiency testing criteria for clearance level in solid waste gamma measurement in Taiwan.

    Science.gov (United States)

    Chen, Chun-Liang; Wang, Jeng-Jong; Chiu, Huang-Sheng

    2013-11-01

    To guarantee the measurement quality for clearance level in solid waste material, the Institute of Nuclear Energy Research (INER) established the criteria for proficiency testing of clearance level measurement. INER and the Taiwan Accreditation Foundation (TAF) organized the Technique Committee Meeting twice to discuss these criteria in 2011. The participating laboratories must completely conform to the ISO/IEC 17025, and they also must meet the requirements of the criteria. According to the criteria, the participating laboratories analyzed the minimum detectable amount (MDA) and that should be less than 20% of the clearance level (AMDA) given in the Atomic Energy Council's (AEC) "Regulations on Clearance Level for Radioactive Waste Management". The testing results should conform to the deviation and traceability requirements. PMID:23591296

  17. Radial Clearance Control and Internal Leakage Analysis of a Tri-Proportion Controller

    Institute of Scientific and Technical Information of China (English)

    LI Dai-jin; ZHANG Yu-wen; TANG Hao; DANG Jian-jun; LUO Kai

    2009-01-01

    The tri-propellant thermal propulsion system is one of the hottest subjects in the.field of underwater vehicles recently. To improve efficiency of underwater vehicles, a method of radial clearance control of the tri-proportion has been proposed. Based on analyzing the factors which influence the pressure decrease and leakage of the tri-proportion controller, a method is used for precision analysis and proportion adjustment by using the median optimizing theory. Analysis results show that accuracy of the proportion controller is dependent on all the leakage, while the leakage is decided by radial clearance and pressure; the leakage can be controlled effectively and the accuracy of the proportion can be improved with the radial clearance control method. The method of accuracy analysis and clearance control has value on the design of various hydraulic motors.

  18. Using radioaerosols to monitor physiotherapy-enhanced mucus clearance at different levels of the bronchial tree

    Energy Technology Data Exchange (ETDEWEB)

    Hasani, A.; Pavia, D.; Clarke, S.W.; Agnew, J.E. (Royal Free Hospital, London (United Kingdom))

    1993-01-01

    Patients with airways obstruction often find it difficult to clear excess lung secretions. Frequent coughing can clear the larger airways but may itself further damage the airways ciliated epithelium. Various physiotherapy regimes have been proposed yet objective evidence of their efficacy is sparse. Deposited aerosol particles - with an appropriate label for gamma imaging - can track clearance from different lung regions. Published reports have however tended to be equivocal in respect of clearance from the more distal conducting airways. Questions also arise as to coordination of transport rates at different levels of the bronchial tree. We therefore sought to re-assess requirements for effective analysis of physiotherapy-enhanced clearance to yield data on both peripheral and central airways clearance. (author).

  19. Increased hepatic insulin clearance after Roux-en-Y gastric bypass

    DEFF Research Database (Denmark)

    Bojsen-Møller, Kirstine N; Dirksen, Carsten; Jørgensen, Nils B;

    2013-01-01

    Context:Roux-en-Y gastric bypass (RYGB) improves glucose tolerance and ameliorates fasting hyperinsulinemia within days after surgery. Improvements in hepatic insulin sensitivity and insulin clearance could contribute importantly to these effects.Objective:The objective of the investigation...

  20. The Swedish nuclear industry way to approach higher demands on characterisation prior to clearance

    International Nuclear Information System (INIS)

    The Swedish Radiation Safety Authority (SSM) has introduced new regulations for clearance SSMFS 2011:2 'Regulations concerning clearance of material, rooms, buildings and soil from activities with ionizing radiation'. The new regulations came into force January 1, 2012. Compared to the previous regulations these new regulations have a broader scope and have introduced new conditions such as nuclide specific clearance levels. Clearance is practiced to reduce the amount of radioactive waste generated. Cleared material can be reused, recycled or if these two possibilities are not available, disposed of as conventional waste. To be able to meet the requirements for clearance the Swedish nuclear industry has jointly developed guidance for clearance in the form of a handbook and a training course covering the competence requirements in the new regulations. The handbook was developed by a team of representatives from the Swedish nuclear license holders managed by Studsvik on behalf of Swedish Nuclear Fuel and Waste Management Company (SKB). The training program was developed in co-operation between Nuclear Safety and training Company (KSU) and Studsvik on behalf of the Swedish nuclear license holders. A major challenge in the adoption to the new regulations is how to provide robust yet cost effective characterisation data. This is especially difficult for mobile materials and equipment which cannot be fully tracked but also for other materials and areas where the nuclide fingerprint has varied over the years. To be able to deal with these issues a lot of attention has to be paid to the historical inventory records and traceability in the clearance process. Materials, rooms and buildings have been divided in four categories with different requirements on frequency and requirements of measurements. The categories are named 'extremely small risk', 'small risk', 'risk' and 'known contamination above clearance levels'. The two day training course is dived into seven parts

  1. Rapid clearance of xanthines from airway and pulmonary tissues

    International Nuclear Information System (INIS)

    The airway and pulmonary fate of two antiasthma xanthines was examined in a guinea pig perfused lung preparation where the airway mechanics and airway microvascular perfusion are maintained at near normal values. 14C-theophylline or 14C-enprofylline was infused for 10, 30, and 300 s into the pulmonary artery of the guinea pig isolated lung. The radioactivity increased rapidly (within 10 s) in tracheobronchial as well as in lung tissue, confirming that the large airway microcirculation was well supplied also by the perfusion. The effluent concentrations of total 3H and 14C radioactivity at the onset, during, and after intrapulmonary infusion of 14C-labeled xanthines and 3H-sucrose were closely associated, suggesting that the xanthines, like sucrose, largely distributed in extracellular fluid and were not taken up by the tissues. No metabolites of enprofylline or theophylline could be detected in the lung tissue or lung effluent, suggesting that xanthines are not biotransformed by the guinea pig lung. After intratracheal instillation of 14C-theophylline, the peak radioactivity in the lung effluent appeared in the second 15-s fraction after instillation, and after 10 and 60 min, 68.1 +/- 4.7% and 86.9 +/- 8.4%, respectively, of the given dose had appeared in the lung effluent. The present data suggest a mainly extracellular distribution and a rapid clearance of xanthines from the lung and airway tissues. The rapid disappearance of topical theophylline may explain the lack of success of inhalation therapy with this drug

  2. Clearance of BWR steam piping by off line chemical decontamination

    International Nuclear Information System (INIS)

    This paper deals with laboratory tests that analyze the acid attack of metallic samples, contaminated by Co60 in the Caorso nuclear power plant in Italy. The main aim was to establish the working parameters of the decontamination plant for metallic components. The study took into consideration the steam piping, located in the turbine building, that is, piping from the main header to the high pressure turbine stage, as well as other steam piping, connecting different turbine stages or that had other functions. The Co60 is produced in the reactor vessel by neutron capture in the iron nuclei of the materials located in the pressure vessel. The coolant erodes the steel surfaces and deposits these products along the piping. In the first phase of the activity the chemical decontamination process was simulated in the laboratory, in particular the acid attack and the subsequent high pressure water washing. For the various parts of the piping (straight lines, bends, intersections) smear tests enabled the radioactivity distribution to be determined. Metallographic analyses of the samples, core bored by the piping, determined the composition of the deposit (crud) on the internal surface of the components and the radioactivity along the thickness of the crud, and consequently the time of the acid attack in order to obtain the Clearance. Numerical simulations of the Co60 deposition by means of CFD codes are currently being carried out in order to compare the results to those obtained experimentally. This will enable us to classify the systems from a radiological point of view by estimating ‘a priori’ the time required for decontamination

  3. Clearance of BWR steam piping by off line chemical decontamination

    Energy Technology Data Exchange (ETDEWEB)

    Pilo, F. [Department of Mechanical Nuclear and Production Engineering, University of Pisa (Italy); Fontani, E. [Sogin Spa, Caorso Nuclear Power Plant (Italy); Aquaro, D., E-mail: aquaro@ing.unipi.it [Department of Mechanical Nuclear and Production Engineering, University of Pisa (Italy)

    2014-04-01

    This paper deals with laboratory tests that analyze the acid attack of metallic samples, contaminated by Co{sup 60} in the Caorso nuclear power plant in Italy. The main aim was to establish the working parameters of the decontamination plant for metallic components. The study took into consideration the steam piping, located in the turbine building, that is, piping from the main header to the high pressure turbine stage, as well as other steam piping, connecting different turbine stages or that had other functions. The Co{sup 60} is produced in the reactor vessel by neutron capture in the iron nuclei of the materials located in the pressure vessel. The coolant erodes the steel surfaces and deposits these products along the piping. In the first phase of the activity the chemical decontamination process was simulated in the laboratory, in particular the acid attack and the subsequent high pressure water washing. For the various parts of the piping (straight lines, bends, intersections) smear tests enabled the radioactivity distribution to be determined. Metallographic analyses of the samples, core bored by the piping, determined the composition of the deposit (crud) on the internal surface of the components and the radioactivity along the thickness of the crud, and consequently the time of the acid attack in order to obtain the Clearance. Numerical simulations of the Co{sup 60} deposition by means of CFD codes are currently being carried out in order to compare the results to those obtained experimentally. This will enable us to classify the systems from a radiological point of view by estimating ‘a priori’ the time required for decontamination.

  4. Relationship of Insulin Sensitivity, Insulin Secretion, and Adiposity With Insulin Clearance in a Multiethnic Population

    OpenAIRE

    Lorenzo, Carlos; Hanley, Anthony J.G.; Wagenknecht, Lynne E; Rewers, Marian J.; Stefanovski, Darko; Goodarzi, Mark O.; Haffner, Steven M

    2012-01-01

    OBJECTIVE We aimed to examine insulin clearance, a compensatory mechanism to changes in insulin sensitivity, across sex, race/ethnicity populations, and varying states of glucose tolerance. RESEARCH DESIGN AND METHODS We measured insulin sensitivity index (S I), acute insulin response (AIR), and metabolic clearance rate of insulin (MCRI) by the frequently sampled intravenous glucose tolerance test in 1,295 participants in the Insulin Resistance Atherosclerosis Study. RESULTS MCRI was positive...

  5. Clearance from the mouse brain by convection of interstitial fluid towards the ventricular system

    OpenAIRE

    Bedussi, Beatrice; van Lier, Monique G. J. T. B.; Bartstra, Jonas W.; de Vos, Judith; Siebes, Maria; VanBavel, Ed; Bakker, Erik N.T.P.

    2015-01-01

    Background In the absence of a true lymphatic system in the brain parenchyma, alternative clearance pathways for excess fluid and waste products have been proposed. Suggested mechanisms for clearance implicate a role for brain interstitial and cerebrospinal fluids. However, the proposed direction of flow, the anatomical structures involved, and the driving forces are controversial. Methods To trace the distribution of interstitial and cerebrospinal fluid in the brain, and to identify the anat...

  6. Flutter clearance of the horizontal tail of the Bellanca Skyrocket II airplane

    Science.gov (United States)

    Ricketts, R. H.; Cazier, F. W., Jr.; Farmer, M. G.

    1982-01-01

    The Skyrocket II is an all composite constructed experimental prototype airplane. A flutter clearance program was conducted on the horizontal tail so that the airplane could be safely flown to acquire natural laminar flow aerodynamic data. Ground vibration test data were used in a lifting surface flutter analysis to predict symmetric and antisymmetric flutter boundaries. Subcritical response data which were acquired during flight tests are compared with the analytical results. The final flutter clearance placard speed was based on flight test data.

  7. Error Modelling and Experimental Validation of a Planar 3-PPR Parallel Manipulator with Joint Clearances

    OpenAIRE

    Wu, Guanglei; Shaoping, Bai; Jørgen A., Kepler; Caro, Stéphane

    2012-01-01

    This paper deals with the error modelling and analysis of a 3-\\underline{P}PR planar parallel manipulator with joint clearances. The kinematics and the Cartesian workspace of the manipulator are analyzed. An error model is established with considerations of both configuration errors and joint clearances. Using this model, the upper bounds and distributions of the pose errors for this manipulator are established. The results are compared with experimental measurements and show the effectivenes...

  8. Analysis of grease contamination influence on the internal radial clearance of ball bearings by thermographic inspection

    OpenAIRE

    Mišković Žarko Z.; Mitrović Radivoje M.; Stamenić Zoran V.

    2016-01-01

    One of the most important factors influencing ball bearings service life is its internal radial clearance. However, this parameter is also very complex because it depends on applied radial load and ball bearings dimensions, surface finish and manufacturing materials. Thermal condition of ball bearings also significantly affects internal radial clearance. Despite many researches performed in order to find out relevant facts about different aspects of ball be...

  9. Whole body clearance of norepinephrine. The significance of arterial sampling and of surgical stress

    DEFF Research Database (Denmark)

    Hilsted, J; Christensen, N J; Madsbad, S

    1983-01-01

    The whole body clearance of norepinephrine (NE) was measured in seven patients pre- and postoperatively. L[(3)H]NE was infused intravenously for 90 min and steady-state concentrations of L[(3)H]NE were measured at 75 and 90 min in both arterial and peripheral venous blood. Preoperatively, in the ......, in the resting supine position, the clearance values based on arterial and venous sampling averaged 1.4 and 2.5 liter/min, respectively (P...

  10. Lung clearance of 99mTc-DTPA in systemic lupus erythematosus

    Directory of Open Access Journals (Sweden)

    P.T.R. Dalcin

    2002-06-01

    Full Text Available The early demonstration of lung involvement in systemic lupus erythematosus (SLE patients is a difficult but important task. In the present study we attempted to identify abnormalities in pulmonary clearance of 99mTc-DTPA in SLE, correlating their clearance data with clinical findings and disease activity. Forty-six consecutive SLE patients with and without active disease (LACC score and 30 normal volunteers were studied. All subjects were submitted to pulmonary scintigraphy with 99mTc-DTPA to evaluate the pulmonary clearance, and to a chest X-ray, and SLE patients were submitted to tests of disease activity, spirometry, arterial blood gases and tests to assess acute-phase proteins. Pulmonary clearance was faster in SLE patients with active disease when compared to normal controls [half-life of 67.04 min (51.52-82.55 min in active SLE versus 85.87 min (78.85-92.87 min in controls, P<0.05] and there was a higher frequency of abnormal clearance rates in patients with active disease (11 of 26 patients, 42.3% when compared with SLE patients without disease activity (2 of 20 patients, 10% (P = 0.04. A significant correlation was observed between the clearance rates and cough (P<0.05, but not between the clearance rates and dyspnea symptoms or radiological findings, duration of SLE disease, antinuclear antibody titers and patterns, C-reactive protein or anti-double stranded DNA antibodies. We conclude that the pulmonary clearance of 99mTc-DTPA is increased in SLE patients with active disease.

  11. Lung clearance of 99m Tc- DTPA in systemic lupus erythematous

    International Nuclear Information System (INIS)

    The early demonstration of lung involvement in systemic lupus erythematosus (SLE) patients is a difficult but important task. In the present study we attempted to identify abnormalities in pulmonary clearance of 99 mTc-DTPA in SLE, correlating their clearance data with clinical findings and disease activity. Forty-six consecutive SLE patients with and without active disease (LACC score) and 30 normal volunteers were studied. All subjects were submitted to pulmonary scintigraphy with 99 mTc-DTPA to evaluate the pulmonary clearance, and to a chest X-ray, and SLE patients were submitted to tests of disease activity, spirometry, arterial blood gases and tests to assess acute-phase proteins. Pulmonary clearance was faster in SLE patients with active disease when compared to normal controls [half-life of 67.04 min (51.52-82.55 min) in active SLE versus 85.87 min (78.85-92.87 min) in controls, P<0.05] and there was a higher frequency of abnormal clearance rates in patients with active disease (11 of 26 patients, 42.3%) when compared with SLE patients without disease activity (2 of 20 patients, 10%) (P = 0.04). A significant correlation was observed between the clearance rates and cough (P<0.05), but not between the clearance rates and dyspnoea symptoms or radiological findings, duration of SLE disease, antinuclear antibody titers and patterns, C-reactive protein or anti-double stranded DNA antibodies. We conclude that the pulmonary clearance of 99 m Tc-DTPA is increased in SLE patients with active disease. (author)

  12. Effect of surface-active substance on nasal mucociliary clearance time

    DEFF Research Database (Denmark)

    Outzen, K E; Svane-Knudsen, V

    1993-01-01

    Mucociliary clearance measured by saccharin clearance time is depending on ciliary function and on the physiological characteristics of mucus. The aim of this study was to determine whether the application of surface-active substances changed the mucociliary transport time. Twenty healthy persons...... with surface-active substances. This difference was not found 2 h later. Our assay indicates that surfactant increases the rate of mucociliary transport in the upper respiratory tract....

  13. Error modelling and experimental validation of a planar 3-PPR parallel manipulator with joint clearances

    DEFF Research Database (Denmark)

    Wu, Guanglei; Bai, Shaoping; Kepler, Jørgen Asbøl;

    2012-01-01

    This paper deals with the error modelling and analysis of a 3-PPR planar parallel manipulator with joint clearances. The kinematics and the Cartesian workspace of the manipulator are analyzed. An error model is established with considerations of both configuration errors and joint clearances. Using...... this model, the upper bounds and distributions of the pose errors for this manipulator are established. The results are compared with experimental measurements and show the effectiveness of the error prediction model....

  14. Effects of Floating Ring Bearing Manufacturing Tolerance Clearances on the Dynamic Characteristics for Turbocharger

    Institute of Scientific and Technical Information of China (English)

    WANG Longkai; BIN Guangfu; LI Xuejun; ZHANG Xuefeng

    2015-01-01

    The inner and outer oil film dynamic characteristic coefficients of floating ring bearings(FRBs) change due to the manufacturing tolerance of the floating ring, journal and intermediate, which leads to high-speed turbocharger’s vibration too large and even causes nonlinear vibration accident. However, the investigation of floating ring bearing manufacturing tolerance clearance on the rotordynamic characteristics is less at present. In order to study the influence law of inner and outer clearance on turbocharger vibration, the rotor dynamic motion equations of turbocharger supported in FRBs are derived by analyzing the size relations between floating ring, journal and intermediate for the inner and outer oil film clearances, the time transient response analysis for combination of FRBs clearance are developed. A realistic turbocharger is taken as a research object, the FE model of the turbocharger with FRBs is modeled. Under the conditions of four kinds of limit state bearing clearances for inner and outer oil film, the nonlinear transient analyses are performed based on the established FE dynamic models of the nonlinear rotor-FRBs system applied incentive combinations of gravity and unbalance force, respectively. From the waterfall, the simulation results show that the speed for the appearance of fractional frequency is not identical and the amplitude magnitude is different under the four kinds of bearing manufacturing tolerance limit clearances, and fractional frequency does not appear in the turbocharger and the amplitude is minimum under the ODMin/IDMax bearing manufacturing tolerance clearances. The turbocharger vibration is reduced by controlling the manufacturing tolerance clearance combinations of FRBs, which is helpful for the dynamic design and production-manufacturing of high-speed turbocharger.

  15. Metabolic clearance of recombinant human growth hormone in health and chronic renal failure.

    OpenAIRE

    D. Haffner; Schaefer, F.; Girard, J.; Ritz, E.; Mehls, O

    1994-01-01

    Despite the increasing therapeutic use of recombinant human growth hormone (rhGH), its metabolic clearance has not been investigated in detail. To evaluate the kinetics of rhGH as a possible function of GH plasma concentration and glomerular filtration rate (GFR), we investigated the steady state metabolic clearance rate (MCR), disappearance half-life, and apparent volume of distribution of rhGH at low and high physiological as well as supraphysiological plasma GH levels during pharmacologica...

  16. The value of the amylase/creatinine clearance ratio in the diagnosis of acute pancreatitis.

    Science.gov (United States)

    Solomon, A R

    1978-01-01

    Acute pancreatitis usually confronts the clinician with a difficult diagnostic task. For years, the primary laboratory diagnostic tests were the serum and urine amylase and the serum lipase determinations. Recent studies have introduced the concept of the amylase/creatinine clearance ratio as a means of increasing the specificity of the laboratory diagnosis. This paper reviews the laboratory evaluation of acute pancreatitis with emphasis on the rationale, derivation, and specificity of the amylase/creatinine clearance ratio.

  17. Decreased insulin clearance in individuals with elevated 1-h post-load plasma glucose levels.

    Directory of Open Access Journals (Sweden)

    Maria Adelaide Marini

    Full Text Available Reduced insulin clearance has been shown to predict the development of type 2 diabetes. Recently, it has been suggested that plasma glucose concentrations ≥ 8.6 mmol/l (155 mg/dl at 1 h during an oral glucose tolerance test (OGTT can identify individuals at high risk for type 2 diabetes among those who have normal glucose tolerance (NGT 1 h-high. The aim of this study was to examine whether NGT 1 h-high have a decrease in insulin clearance, as compared with NGT individuals with 1-h post-load glucose <8.6 mmol/l (l (155 mg/dl, NGT 1 h-low. To this end, 438 non-diabetic White individuals were subjected to OGTT and euglycemic-hyperinsulinemic clamp to evaluate insulin clearance and insulin sensitivity. As compared with NGT 1 h-low individuals, NGT 1 h-high had significantly higher 1-h and 2-h post-load plasma glucose and 2-h insulin levels as well as higher fasting glucose and insulin levels. NGT 1 h-high exhibited also a significant decrease in both insulin sensitivity (P<0.0001 and insulin clearance (P = 0.006 after adjusting for age, gender, adiposity measures, and insulin sensitivity. The differences in insulin clearance remained significant after adjustment for fasting glucose (P = 0.02 in addition to gender, age, and BMI. In univariate analyses adjusted for gender and age, insulin clearance was inversely correlated with body weight, body mass index, waist, fat mass, 1-h and 2-h post-load glucose levels, fasting, 1-h and 2-h post-load insulin levels, and insulin-stimulated glucose disposal. In conclusion, our data show that NGT 1 h-high have a reduction in insulin clearance as compared with NGT 1 h-low individuals; this suggests that impaired insulin clearance may contribute to sustained fasting and post-meal hyperinsulinemia.

  18. Exercise increases the lung clearance of inhaled Tc-99m DTPA

    International Nuclear Information System (INIS)

    It has been suggested that blood flow have little effect on the lung clearance of Tc-99m DTPA which depends on the alveolar distension. However an increase of pulmonary blood flow, induces a recruitment of new vascular areas which can enhance this clearance. To assess this hypothesis the pulmonary apical and basal clearances of a sumicronic aerosol of Tc-99m DTPA were studied at rest and at exercise in seven non smoking volunteers in upright posture. As a matter of fact exercising upright is known to increase primarily the apical blood flow. After inhalation the subjects were seated on a bicycle their back against a gamma camera which was linked to a computer. The lung radioactivity was registered successively during a resting and an exercising period. At rest there was a gradient of clearance from the apex to the base of the lung, the apical clearance being significantly higher. At exercise (50 Watts, 60 c. min /sup -1/, 7 min.) this regional gradient was enhanced by a large and significant increase of the apical clearances (0.0340 min /sup -1/ +-0.0063 SD versus 0.00183 min /sup -1/ +- 0.074 SD at rest, n = 7, p < 0.01). By contrast the changes of the basal clearances were slight and unsignificant (0.0146 min /sup -1/ +- 0.0062 SD versus 0.0140 min /sup -1/ +- 0.0082 SD). Since exercise induces little distension of the apical alveoli but drastically enhances the apical blood flow, the observed increase of the apical lung clearance could be primarily attributed to the recruitment of new capillaries induced by exercise in the apices. This led to an increase of the surface area permeability product

  19. Solute clearance measurement in the assessment of dialysis adequacy among African continuous ambulatory peritoneal dialysis patients

    Directory of Open Access Journals (Sweden)

    Aliyu Abdu

    2015-01-01

    Full Text Available Solute clearance measurement is an objective means of quantifying the dose of peritoneal dialysis (PD. Despite continued debate on the interpretation and precise prognostic value of small solute clearance in PD patients, guidelines based on solute clearance values are common in clinical practice. There is limited information on the solute clearance indices and PD adequacy parameters among this predominantly low socioeconomic status PD population. We investigated the solute clearance among continuous ambulatory peritoneal dialysis (CAPD patients at the Charlotte Maxeke Johannesburg Academic Hospital and its relationship with other parameters of PD adequacy. Seventy patients on CAPD were studied in this cross-sectional study. Solute clearance was assessed using urea clearance (Kt/V. Linear regression analysis was used to determine factors associated with solute clearance, while analysis of variance was used to test the influence of weekly Kt/V on blood pressure (BP, hemoglobin (Hb and other biochemical parameters. The mean age of the study population was 37.9 ± 12.4 years, 43% were females and 86% were black Africans. The mean duration on CAPD was 19.7 ± 20.8 months. Mean systolic and diastolic BP were 144 ± 28 and 92 ± 17 mm Hg, respectively. The mean Hb was 11.1 ± 2.2 g/dL and the mean weekly Kt/V was 1.7 ± 0.3. Factors like systolic BP, Hb level, serum levels of cholesterol, calcium, phosphate, parathyroid hormone and albumin were not significantly associated with the weekly Kt/V. We conclude that the dose of PD received by the majority of our patients in terms of the weekly Kt/V is within the recommended values and that this finding is significant considering the low socioeconomic background of our patients. There is no significant association between Kt/V and other indices of dialysis adequacy.

  20. Lung clearance of {sup 99m} Tc- DTPA in systemic lupus erythematous

    Energy Technology Data Exchange (ETDEWEB)

    Dalcin, P.T.R; Barreto, S.S.M.; Xavier, R.M.; Brenol, J.C.T. [Rio Grande do Sul Univ., Porto Alegre, RS (Brazil). Hospital de Clinicas. Dept. de Medicina Interna; Cunha, R.D.; Marroni, B.J. [Rio Grande do Sul Univ., Porto Alegre, RS (Brazil). Hospital de Clinicas. Servico de Medicina Nuclear]. E-mail: rxavier@hcpa.ufrgs.br

    2002-06-01

    The early demonstration of lung involvement in systemic lupus erythematosus (SLE) patients is a difficult but important task. In the present study we attempted to identify abnormalities in pulmonary clearance of 99 mTc-DTPA in SLE, correlating their clearance data with clinical findings and disease activity. Forty-six consecutive SLE patients with and without active disease (LACC score) and 30 normal volunteers were studied. All subjects were submitted to pulmonary scintigraphy with 99 mTc-DTPA to evaluate the pulmonary clearance, and to a chest X-ray, and SLE patients were submitted to tests of disease activity, spirometry, arterial blood gases and tests to assess acute-phase proteins. Pulmonary clearance was faster in SLE patients with active disease when compared to normal controls [half-life of 67.04 min (51.52-82.55 min) in active SLE versus 85.87 min (78.85-92.87 min) in controls, P<0.05] and there was a higher frequency of abnormal clearance rates in patients with active disease (11 of 26 patients, 42.3%) when compared with SLE patients without disease activity (2 of 20 patients, 10%) (P = 0.04). A significant correlation was observed between the clearance rates and cough (P<0.05), but not between the clearance rates and dyspnoea symptoms or radiological findings, duration of SLE disease, antinuclear antibody titers and patterns, C-reactive protein or anti-double stranded DNA antibodies. We conclude that the pulmonary clearance of 99 m Tc-DTPA is increased in SLE patients with active disease. (author)

  1. Effects of lung volume on clearance of solutes from the air spaces of lungs

    International Nuclear Information System (INIS)

    Several investigators have shown that the clearance rate of aerosolized 99mTc-labeled diethylenetriamine pentaacetate (DTPA, mol wt = 492, radius = 0.6 nm) from the air spaces of the lungs of humans and experimental animals increases with lung volume. To further investigate this phenomenon we performed a compartmental analysis of the 2-h clearance of DTPA from the lungs of anesthetized sheep using a new method to more accurately correct for the effects of DTPA recirculation. This analysis showed that the DTPA clearance in eight sheep ventilated with zero end-expired pressure was best described by a one-compartment model with a clearance rate of 0.42 +/- 0.15%/min. Ventilating eight sheep with an end-expired pressure of 10 cmH2O throughout the study increased the end-expired volume 0.4 +/- 0.1 liter BTPS and created a clearance curve that was best described by a two-compartment model. In these sheep 56 +/- 16% of the DTPA cleared from the lungs at a rate of 7.9 +/- 2.9%/min. The remainder cleared at a rate similar to that measured in the sheep ventilated with zero end-expired pressure (0.35 +/- 0.18%/min). Additional control and lung inflation experiments were performed using /sup 99m/Tc-labeled human serum albumin (mol wt = 66,000, radius = 3.6 nm). In six control sheep ventilated with zero end-expired pressure the albumin clearance was best described by a one-compartment model with a clearance rate of 0.06 +/- 0.02%/min. The clearance rate in six sheep with increased lung volume was slightly larger (0.09 +/- 0.02, P less than 0.05) but was well described by a one-compartment model

  2. Chylous leakage post mastectomy and axillary clearance: clinical aspect, causes and review of literature.

    Science.gov (United States)

    Chan, A C; Sarojah, A

    2013-06-01

    Chylous leakage after mastectomy & axillary clearance is a rare complication. The incidence is less than 0.5%. Anatomical variations in the termination of thoracic duct can occur, rendering it susceptible to injury during axillary dissection. Most chyle leaks in the axilla are managed through conservative measures. Surgical intervention is required in high output chylous leaks. We encountered a case of chylous leak post mastectomy with axillary clearance, which was successfully treated conservatively.

  3. Effect of high mannose glycan pairing on IgG antibody clearance.

    Science.gov (United States)

    Liu, Yaoqing Diana; Flynn, Gregory C

    2016-05-01

    IgG antibodies contain N-linked glycans on the Fc portion of each heavy chain. The glycan on one heavy chain can either match the glycan on the other heavy chain (symmetrical pairing) or be different (asymmetrical pairing). These Fc glycans influence effector functions and can alter clearance rates. Previous studies showing that high mannose forms result in faster mAb clearance in humans were incapable of differentiating the impact of symmetrically vs. asymmetrically paired HM forms, and, therefore, the effect of pairing on clearance was not clear. Traditional analytical methods, which are used to measure glycans in such studies, do not determine the number of HM glycans per antibody. With a sensitive method designed to measure HM pairing, we followed the levels of symmetrically and asymmetrically paired HM on antibodies in human pharmacokinetic serum samples to determine the impact of Fc HM glycan pairing on therapeutic human IgG clearance in humans. The two HM paired forms cleared at the same rate, indicating that the effect on clearance was not proportional to the degree of modification. Since both forms can exist on therapeutic antibodies and the ratio can differ between products, measuring their relative levels is necessary to properly estimate effects on clearance. PMID:26992607

  4. Implications of human nasal clearance studies for the interpretation of nose blow and bioassay sample measurements

    International Nuclear Information System (INIS)

    The Smith-Etherington extrathoracic (ET) clearance model has been developed to describe clearance from the human nasal passage as observed for 1.5, 3 and 6-μm monodisperse particles inhaled by participants while sitting or at light exercise. Model parameter values have been determined for 22 sets of nasal clearance data, from which typical nasal clearance parameter values have been derived. In this investigation, the faecal excretion of 5 μm activity median aerodynamic diameter (AMAD) Type S 239Pu was calculated for three sets of model parameter values i.e. typical values and those determined for two experiments that respectively exhibited particularly rapid and slow clearance. The study has shown that a greater fraction of material deposited in ET is cleared to the GI tract, and that this clearance takes place over a longer period than assumed by the Human Respiratory Tract Model for Radiological Protection. The study has also shown that deliberate nose blow sampling might potentially be developed to determine the order of magnitude of intakes. (author)

  5. The effects of tangential radiotherapy on lung clearance in breast cancer patients

    International Nuclear Information System (INIS)

    Purpose: The aim of this study was to investigate the effects of tangential radiotherapy (RT) on lung clearance in the patients with breast cancer by using 99mTc-DTPA aerosol scintigraphy. Material and methods: Thirty-three female patients [non-smoker: 20, ex-smoker: 13] performed surgery and systemic chemotherapy for breast carcinoma [47±13 years] were included in the study. All patients underwent 99mTc-DTPA aerosol scintigraphy prior to RT (preRT), midway through RT (midRT) and after RT (postRT). Total dose was 50 Gy in modified radical mastectomy and 60 Gy in lumpectomy (2 Gy/fraction). Posterior dynamic images of lungs were obtained immediately after the inhalation of 99mTc-DTPA aerosol. Results: Pulmonary function tests were normal in three measurements for all cases. In the ex-smokers, there was no significant difference among preRT, midRT and postRT clearance values in both lungs. PreRT lung clearance in non-smoker group did not differ from that in ex-smokers. However, the lung clearance for non-smoker group showed significantly increase following RT. Conclusion: In this study, we observed that tangential radiotherapy caused an increase in the lung clearance in the cases of non-smokers even in non-irradiated lung, and that the effect of RT on lung clearance was closely depended on smoking habit before RT

  6. When a Cleared Rape Is Not Cleared: A Multilevel Study of Arrest and Exceptional Clearance.

    Science.gov (United States)

    Walfield, Scott M

    2016-05-01

    As rape remains one of the most underreported and least likely to be cleared of the violent crimes, it is of paramount importance to understand the factors associated with the likelihood of a case being cleared by law enforcement. This study uses data from the National Incident-Based Reporting System (NIBRS) and the Law Enforcement Management and Administrative Statistics (LEMAS), and a multilevel modeling approach to examine the relationship between victim, offender, incident, and police department characteristics contrasting the two types of clearance: arrest and exceptional clearance. The latter occurs due to reasons outside of law enforcement's control and despite being considered cleared, the offender is not arrested, charged, nor turned over for prosecution. Of the 16,231 cleared rapes in 238 departments, nearly half (47%) results in exceptional clearance when the victim refuses to cooperate or when prosecution is declined. Incident-level variables have a greater effect on the likelihood of exceptional clearance than victim and offender variables. The department explained a nontrivial amount of variation in the dependent variable, as 37% of the variance in type of clearance was between-department variation. Implications for future research on exceptional clearance and NIBRS are discussed. PMID:25646164

  7. AARC Clinical Practice Guideline: Effectiveness of Pharmacologic Airway Clearance Therapies in Hospitalized Patients.

    Science.gov (United States)

    Strickland, Shawna L; Rubin, Bruce K; Haas, Carl F; Volsko, Teresa A; Drescher, Gail S; O'Malley, Catherine A

    2015-07-01

    Aerosolized medications are used as airway clearance therapy to treat a variety of airway diseases. These guidelines were developed from a systematic review with the purpose of determining whether the use of these medications to promote airway clearance improves oxygenation and respiratory mechanics, reduces ventilator time and ICU stay, and/or resolves atelectasis/consolidation compared with usual care. Recombinant human dornase alfa should not be used in hospitalized adult and pediatric patients without cystic fibrosis. The routine use of bronchodilators to aid in secretion clearance is not recommended. The routine use of aerosolized N-acetylcysteine to improve airway clearance is not recommended. Aerosolized agents to change mucus biophysical properties or promote airway clearance are not recommended for adult or pediatric patients with neuromuscular disease, respiratory muscle weakness, or impaired cough. Mucolytics are not recommended to treat atelectasis in postoperative adult or pediatric patients, and the routine administration of bronchodilators to postoperative patients is not recommended. There is no high-level evidence related to the use of bronchodilators, mucolytics, mucokinetics, and novel therapy to promote airway clearance in these populations. PMID:26113566

  8. Effects of sustained exercise on pulmonary clearance of aerosolized 99mTc-DTPA

    International Nuclear Information System (INIS)

    The effects of intensive prolonged exercise on the pulmonary clearance rate of aerosolized 99mTc-labeled diethylenetriaminepentaacetate (99mTc-DTPA) and pulmonary mechanics were studied in seven healthy nonsmoking volunteers. 99mTc-DTPA clearance and pulmonary mechanics (lung volumes and compliance) were assessed before and after 75 min of constant-load exercise performed on a treadmill, corresponding to 75% of maximal O2 uptake. Because both clearance measurements were made in similar conditions of pulmonary blood flow, respiratory rate, and tidal volume, changes in clearance rate can be assumed to represent changes of alveolar epithelial permeability. After exercise, total, apical, and basal clearance were significantly increased (P less than 0.01, 0.05, and 0.05, respectively) and the increases in total clearance and tidal volume observed during exercise were significantly correlated (P less than 0.05). In contrast, no significant change was found in pulmonary mechanics. These results show that prolonged intensive exercise induces an increase in epithelial permeability, which appears to be related to the mechanical effects of sustained increased ventilation. Because no change was evidenced in pulmonary volumes or in lung elasticity, our results suggest that this increase may result from alteration of the intercellular tight junctions rather than from a surfactant deficiency

  9. Experimental Investigation of Factors Influencing Operating Rotor Tip Clearance in Multistage Compressors

    Directory of Open Access Journals (Sweden)

    Reid A. Berdanier

    2015-01-01

    Full Text Available An analysis of compressor rotor tip clearance measurements using capacitance probe instrumentation is discussed for a three-stage axial compressor. Thermal variations and centrifugal effects related to rotational speed changes affect clearance heights relative to the assembled configuration. These two primary contributions to measured changes are discussed both independently and in combination. Emphasis is given to tip clearance changes due to changing loading condition and at several compressor operating speeds. Measurements show a tip clearance change approaching 0.1 mm (0.2% rotor span when comparing a near-choke operating condition to a near-stall operating condition for the third stage. Additional consideration is given to environmental contributions such as ambient temperature, for which changes in tip clearance height on the order of 0.05 mm (0.1% rotor span were noted for temperature variations of 15°C. Experimental compressor operating clearances are presented for several temperatures, operating speeds, and loading conditions, and comparisons are drawn between these measured variations and predicted changes under the same conditions.

  10. Dynamic analysis of planar mechanical systems with clearance joints using a new nonlinear contact force model

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xupeng; Liu, Geng; Ma, Shangjun [Northwestern Polytechnical University, Xi' an (China)

    2016-04-15

    We investigated the dynamic behavior of planar mechanical systems with clearance joints. First, the contact effect in clearance joint was studied using a new nonlinear contact force model, and the rationality of this model was verified by the results of numerical simulations, which are based on a journal and bearing contact model. Then, the dynamic characteristics of a planar slider-crank mechanism with clearance were analyzed based on the new nonlinear contact force model, and the friction effect of clearance joint was also considered using modified Coulomb friction model. Finally, the numerical results of the influence of clearance size on the acceleration of slider are presented, and compared with the published experimental results. The numerical and experimental results show that the new nonlinear contact force model presented in this paper is an effective method to predict the dynamic behavior of planar mechanical system with clearance joints, and appears to be suitable for a wide range of impact situations, especially with low coefficient of restitution.

  11. Effects of semi-floating ring bearing outer clearance on the subsynchronous oscillation of turbocharger rotor

    Science.gov (United States)

    Liang, Feng; Zhou, Ming; Xu, Quanyong

    2016-06-01

    Semi-floating ring bearing(SFRB) is developed to control the vibration of turbocharger rotor. The outer clearance of SFRB affects the magnitude and frequency of nonlinear whirl motion, which is significant for the design of turbocharger. In order to explore the effects of outer clearance, a transient finite element analysis program for rotor and oil film bearing is built and validated by a published experimental case. The nonlinear dynamic behaviors of rotor-SFRB system are simulated. According to the simulation results, two representative subsynchronous oscillations excited by the two bearings respectively are discovered. As the outer clearance of SFRB increases from 24 μm to 60 μm, the low-frequency subsynchronous oscillation experiences three steps, including a strong start, a gradual recession and a combination with the other one. At the same time, the high-frequency subsynchronous oscillation starts to appear gradually, then strengthens, and finally combines. If gravity and unbalance are neglected, the combination will start starts from high rotor speed and extents to low rotor speed, just like a "zipper". It is found from the quantitative analysis that when the outer clearance increases, the vibration amplitude experiences large value firstly, then reduction, and suddenly increasing after combination. A useful design principle of SFRB outer clearance for minimum vibration amplitude is proposed: the outer clearance value should be chosen to keep the frequency of two subsynchronous oscillations clearly separated and their amplitudes close.

  12. Development of a Novel System to Measure a Clearance of a Passenger Platform

    Science.gov (United States)

    Shimizu, M.; Oizumi, J.; Matsuoka, R.; Takeda, H.; Okukura, H.; Ooya, A.; Koike, A.

    2016-06-01

    Clearances of a passenger platform at a railway station should be appropriately maintained for safety of both trains and passengers. In most Japanese railways clearances between a platform and a train car is measured precisely once or twice a year. Because current measurement systems operate on a track, the closure of the track is unavoidable. Since the procedure of the closure of a track is time-consuming and bothersome, we decided to develop a new system to measure clearances without the closure of a track. A new system is required to work on a platform and the required measurement accuracy is less than several millimetres. We have adopted a 3D laser scanner and stop-and-go operation for a new system. The current systems on a track measure clearances continuously at walking speed, while our system on a platform measures clearances at approximately ten metres intervals. The scanner controlled by a PC acquires a set of point data at each measuring station. Edge points of the platform, top and side points of two rails are detected from the acquired point data. Finally clearances of the platform are calculated by using the detected feature points of the platform and the rails. The results of an experiment using a prototype of our system show that the measurement accuracy by our system would be satisfactory, but our system would take more time than the current systems. Since our system requires no closure of a track, we conclude that our system would be convenient and effective.

  13. The mechanism of increased renal clearance of amylase in acute pancreatitis.

    Science.gov (United States)

    Warshaw, A L; Lee, K H

    1976-09-01

    Amylase isoenzymes, separated by polyacrylamide gel electrophoresis, were measures in 25 normal persons (mean amylase to creatinine clearance ratio 3.0%), 15 patients with acute pancreatitis (mean clearance ratio 9.5%, P less than 0.0001), and 6 patients with hyperamylasemia due to common duct stones (mean clearance ratio 4.1%). Two isoamylases (P1, P2) resembling pancreatic isoenzymes and three isoamylases (S1, S2, S3) resembling salivary isoenzymes appeared regularly in normal serum and urine. Salivary amylases predominated in serum, but pancreatic amylases predominated in urine. This finding is consistent with renal clearance of pancreatic amylases exceeding that of salivary amylases under normal conditions. In patients with pancreatitis or common duct stones, essentially all of the increased amylase activity in serum and urine was due to pancreatic isoamylases (P1 and P2) in their normal proportions. No new or altered amylase isoenzymes were detected. The fraction of pancreatic amylases in the serum or urine was identical for the two diseases. Whereas the difference in amylase to creatinine clearance ratios observed between the two groups of patients is not a function of different amylase isoenzymes presented to the kidney, we conclude that the increased amylase clearance in acute pancreatitis is caused by an alteration of renal transfer of amylase, either at the glomerulus or tubule.

  14. Characterizing clearance of helper adenovirus by a clinical rAAV1 manufacturing process.

    Science.gov (United States)

    Thorne, Barbara A; Quigley, Paulene; Nichols, Gina; Moore, Christine; Pastor, Eric; Price, David; Ament, Jon W; Takeya, Ryan K; Peluso, Richard W

    2008-01-01

    Recombinant adeno-associated viral vectors (rAAV) are being developed as gene therapy delivery vehicles and as genetic vaccines, and some of the most scaleable manufacturing methods for rAAV use live adenovirus to induce production. One aspect of establishing safety of rAAV products is therefore demonstrating adequate and reliable clearance of this helper virus by the vector purification process. The ICH Q5A regulatory guidance on viral safety provides recommendations for process design and characterization of viral clearance for recombinant proteins, and these principles were adapted to a rAAV serotype 1 purification process for clinical vectors. Specific objectives were to achieve overall adenovirus clearance factors significantly greater than input levels by using orthogonal separation and inactivation methods, and to segregate adenovirus from downstream operations by positioning a robust clearance step early in the process. Analytical tools for process development and characterization addressed problematic in-process samples, and a viral clearance validation study was performed using adenovirus and two non-specific model viruses. Overall clearance factors determined were >23 LRV for adenovirus, 11 LRV for BVDV, and >23 LRV for AMuLV.

  15. Pulmonary clearance of radiotracers after positive end-expiratory pressure or acute lung injury

    International Nuclear Information System (INIS)

    In anesthetized rabbits we measured clearance from lung to blood of eight aerosolized technetium-99m-labeled compounds: diethylenetriaminepentaacetate (99mTc-DTPA); cytochrome c; myoglobin; a myoglobin polymer; albumin; and anionic, cationic, and neutral dextrans of equivalent molecular size. We investigated the effect of applying positive end-expiratory pressure (PEEP) and, on a subsequent occasion, of injecting oleic acid intravenously to produce acute lung injury on the pulmonary clearance rate. Base-line clearance rates were monoexponential and varied with the molecular weights of the radiotracers. For each tracer the rate of clearance was increased a similar degree by either PEEP or oleic acid. However, with PEEP, clearance remained monoexponential, whereas after oleic acid, smaller molecular-weight radiotracers had multiexponential clearance curves. This suggests that after oleic acid the alveolar epithelium breaks down in a nonuniform fashion. We conclude that differentiation of the effect of PEEP from that of severe lung injury caused by oleic acid is not readily accomplished by either increasing the size of the tracer molecule or by varying the molecular charge

  16. Importance of different clearance options for the dismantling of the NPP Stade (KKS); Bedeutung verschiedener Freigabeoptionen fuer den Rueckbau des KKS

    Energy Technology Data Exchange (ETDEWEB)

    Bacmeister, G.U. [E.ON Kernkraftwerk Stade (Germany)

    2013-07-01

    As a consequence of the IAEA-Safety Guide RS-G 1.7 is an adaption of the clearance level in European and national German law in preparation. This paper analyse the effect of the different clearance levels of the realisation of the clearance, especially if some conditioned clearance according to German law will not exist further more. (orig.)

  17. Changes in glomerular filtration rate, lithium clearance and plasma protein clearances in the early phase after unilateral nephrectomy in living healthy renal transplant donors

    DEFF Research Database (Denmark)

    Strandgaard, S; Kamper, A; Skaarup, P;

    1988-01-01

    1. Glomerular and tubular function was studied before and 2 months after unilateral nephrectomy in 14 healthy kidney donors by measurement of the clearances of 51Cr-labelled ethylenediaminetetra-acetate, lithium, beta 2-microglobulin, albumin and immunoglobulin G. 2. The glomerular filtration rate...

  18. Hepatic clearance of 6 polyaromatic aromatic hydrocarbons by isolated trout livers: Prediction from in vitro clearance by liver S9 fractions

    Science.gov (United States)

    An isolated perfused trout liver preparation was used to evaluate in vitro-to-in vivo metabolism extrapolation procedures for fish. Hepatic clearance (CLH) studies were conducted with six polyaromatic hydrocarbons (PAH) using an experimental design wherein each liver acted as it...

  19. Conventional measurements of GFR using 51Cr-EDTA overestimate true renal clearance by 10 percent

    International Nuclear Information System (INIS)

    It is widely believed that measurement of the area under the plasma clearance curve (AUC) following a single intravenous injection of chromium-51 labelled ethylene diamine tetra-acetic acid (51Cr-EDTA) is a gold standard method for determining glomerular filtration rate (GFR). However, there are reports that 51Cr-EDTA may have a significant extrarenal clearance. The aim of this study was to identify the non-renal component of 51Cr-EDTA plasma clearance contributing to the AUC measurement of GFR. Seventy healthy postmenopausal women (mean age 60 years, range 45-79 years) were injected with 3 MBq 51Cr-EDTA and 0.25 MBq iodine-125 labelled human serum albumin and 11 blood samples taken between 0 and 4 h through an indwelling venous cannula. For the first 21 subjects, two complete urine collections were made 0-2 h and 2-4 h after injection, and for the final 49 patients, four 1-h urine collections were made. The mean 51Cr-EDTA total plasma clearance was 84 ml/min (range 50-132 ml/min). The mean ratio (SEM) of urine to total clearance determined from the cumulative 1-, 2-, 3- and 4-h data was 0.903 (0.018), 0.891 (0.013), 0.898 (0.011) and 0.899 (0.010) respectively and remained constant despite the mean urine concentration decreasing from 122% to 15%/litre during this period. A least squares fit to data from the 238 individual urine collections was used to determine the fraction of the total plasma clearance attributable to renal clearance, α0, and the residual urine volume, ΔV. The results were α0=0.910 (95% CI: 0.889-0.932) and ΔV=14 ml (95% CI: -4 to +34 ml). The overestimation of the true renal clearance of 51Cr-EDTA by the AUC method is believed to be due to the failure of the plasma clearance curve to reach the true terminal exponential by 2 h after injection as usually assumed. As a result, conventional measurements of GFR using 51Cr-EDTA overestimate the true renal clearance of tracer by approximately 10%. (orig.)

  20. Four decades of forest persistence, clearance and logging on Borneo.

    Directory of Open Access Journals (Sweden)

    David L A Gaveau

    Full Text Available The native forests of Borneo have been impacted by selective logging, fire, and conversion to plantations at unprecedented scales since industrial-scale extractive industries began in the early 1970s. There is no island-wide documentation of forest clearance or logging since the 1970s. This creates an information gap for conservation planning, especially with regard to selectively logged forests that maintain high conservation potential. Analysing LANDSAT images, we estimate that 75.7% (558,060 km2 of Borneo's area (737,188 km2 was forested around 1973. Based upon a forest cover map for 2010 derived using ALOS-PALSAR and visually reviewing LANDSAT images, we estimate that the 1973 forest area had declined by 168,493 km2 (30.2% in 2010. The highest losses were recorded in Sabah and Kalimantan with 39.5% and 30.7% of their total forest area in 1973 becoming non-forest in 2010, and the lowest in Brunei and Sarawak (8.4%, and 23.1%. We estimate that the combined area planted in industrial oil palm and timber plantations in 2010 was 75,480 km2, representing 10% of Borneo. We mapped 271,819 km of primary logging roads that were created between 1973 and 2010. The greatest density of logging roads was found in Sarawak, at 0.89 km km-2, and the lowest density in Brunei, at 0.18 km km-2. Analyzing MODIS-based tree cover maps, we estimate that logging operated within 700 m of primary logging roads. Using this distance, we estimate that 266,257 km2 of 1973 forest cover has been logged. With 389,566 km2 (52.8% of the island remaining forested, of which 209,649 km2 remains intact. There is still hope for biodiversity conservation in Borneo. Protecting logged forests from fire and conversion to plantations is an urgent priority for reducing rates of deforestation in Borneo.

  1. Analyses toward factors influencing sealing clearance of a metal rubber seal and derivation of a calculation formula

    Institute of Scientific and Technical Information of China (English)

    Yan Hui; Zhao Yalei; Liu Jianguo; Jiang Hongyuan

    2016-01-01

    Sealing clearance is a key factor for a metal rubber seal’s sealability. The expansion coef-ficient and expansion deformation in the radial direction of metal rubber have been obtained through a thermal expansion experiment of metal rubber. The influence of the elastic modulus to the sealing clearance has been analyzed theoretically. By combining the temperature and elasticity factors of metal rubber with the elastic mechanics theory, the calculation formula of the sealing clearance has been derived, and the values of the sealing clearance and the leakage rate in certain working conditions have been calculated. Experimental results are consistent with calculation results in a high degree. The calculation formula of the sealing clearance can explain the influences of the temperature and elastic modulus factors of metal rubber on the sealing clearance. It can pro-vide guidance for the study of sealing mechanism of metal rubber seals.

  2. Role of membrane-bound IgM in Trypanosoma cruzi evasion from immune clearance.

    Science.gov (United States)

    Garcia, I E; Lima, M R; Marinho, C R; Kipnis, T L; Furtado, G C; Alvarez, J M

    1997-04-01

    We have recently described that Trypanosoma cruzi parasites of the reticulotropic Y strain increase their resistance to antibody-induced clearance during their interaction with the vertebrate host immune system. In the present study, we observed that trypomastigotes of the myotropic CL strain isolated from normal host also display an increased resistance to immune clearance when compared to parasites obtained from immunosuppressed donors. Through fluorescence-activated cell sorting analysis, we have observed that the high expression of membrane-bound IgM antibodies on Y and CL trypomastigotes correlates with their enhanced resistance to Ig-induced clearance. Trypomastigotes from normal mice were essentially refractory to the in vitro binding of immunoglobulins, showing that their membrane structures were completely covered by IgM antibodies. These findings suggest that this isotype does not efficiently mediate immune clearance. Moreover, membrane-bound IgM antibodies limited the amount of IgG attached to the parasite and, as a consequence, impaired efficient immune clearance. Through this mechanism, trypomastigotes of T. cruzi could increase their persistence in the bloodstream thus favoring parasite transmission to its hematophagous host vector in the early acute phase of the disease.

  3. Long-term clearance from small airways in subjects with ciliary dysfunction

    Directory of Open Access Journals (Sweden)

    Hjelte Lena

    2006-05-01

    Full Text Available Abstract The objective of this study was to investigate if long-term clearance from small airways is dependent on normal ciliary function. Six young adults with primary ciliary dyskinesia (PCD inhaled 111 Indium labelled Teflon particles of 4.2 μm geometric and 6.2 μm aerodynamic diameter with an extremely slow inhalation flow, 0.05 L/s. The inhalation method deposits particles mainly in the small conducting airways. Lung retention was measured immediately after inhalation and at four occasions up to 21 days after inhalation. Results were compared with data from ten healthy controls. For additional comparison three of the PCD subjects also inhaled the test particles with normal inhalation flow, 0.5 L/s, providing a more central deposition. The lung retention at 24 h in % of lung deposition (Ret24 was higher (p 24 with slow inhalation flow was 73.9 ± 1.9 % compared to 68.9 ± 7.5 % with normal inhalation flow in the three PCD subjects exposed twice. During day 7–21 the three PCD subjects exposed twice cleared 9 % with normal flow, probably representing predominantly alveolar clearance, compared to 19 % with slow inhalation flow, probably representing mainly small airway clearance. This study shows that despite ciliary dysfunction, clearance continues in the small airways beyond 24 h. There are apparently additional clearance mechanisms present in the small airways.

  4. Interspecies allometric scaling: prediction of clearance in large animal species: part II: mathematical considerations.

    Science.gov (United States)

    Martinez, M; Mahmood, I; Hunter, R P

    2006-10-01

    Interspecies scaling is a useful tool for the prediction of pharmacokinetic parameters from animals to humans, and it is often used for estimating a first-time in human dose. However, it is important to appreciate the mathematical underpinnings of this scaling procedure when using it to predict pharmacokinetic parameter values across animal species. When cautiously applied, allometry can be a tool for estimating clearance in veterinary species for the purpose of dosage selection. It is particularly valuable during the selection of dosages in large zoo animal species, such as elephants, large cats and camels, for which pharmacokinetic data are scant. In Part I, allometric predictions of clearance in large animal species were found to pose substantially greater risks of inaccuracies when compared with that observed for humans. In this report, we examine the factors influencing the accuracy of our clearance estimates from the perspective of the relationship between prediction error and such variables as the distribution of body weight values used in the regression analysis, the influence of a particular observation on the clearance estimate, and the 'goodness of fit' (R(2)) of the regression line. Ultimately, these considerations are used to generate recommendations regarding the data to be included in the allometric prediction of clearance in large animal species. PMID:16958788

  5. Studi Karakteristik Aliran Tiga Dimensi Dan Perpindahan Panas Pada Cascade Airfoil Dengan Pengaruh Clearance

    Directory of Open Access Journals (Sweden)

    Yusuf Wibisono

    2013-03-01

    Full Text Available Dalam dunia teknik khususunya mekanika fluida, aliran tiga dimensi merupakan hal yang sangat penting guna untuk mengetahui fenomena aliran dan perpindahan panas yang terjadi pada bluffbody cascade airfoil. Error atau loses yang terjadi pada cascade airfoil disebabkan oleh adanya aliran sekunder. Error atau loses tersebut menurut penilitian yang terlah dilakukan dapat dikurang dengan aspek clearance. Tujuan dari penilitian ini adalah untuk menganalisa karaktersistik aliran tiga dimensi serta perpindahan panas akibat adanya perubahan jarak antara leading edge antara cascade dan sudut serang serta bentuk geometri. hasil dari simulasi divisualisasikan dalam bentuk velocity dan pressure coefficient. Pada cascade airfoil dengan sudut serang 20° terjadi fenomena pada dinding clearance yaitu tip clearance flow di mana ketika aliran udara melewati dinding akan mengalami up stream yang mengakibatkan arah aliran menuju ke atas, sedangkan pada dinding airfoil ditemukan aliran sekunder berupa curl flow yang akhirnya membentuk spiral point pada trailing edge. Perubahan sudut serang menjadi -20° membuat perbedaan tekanan antara lower side dan upper side semakin lemah, begitu juga tip clearance flow yang terjadi pada wall clearance mengalami perubahan arah menjadi down stream yang mengakibatkan arah aliran menjuu kebawah. Perubahan sudut juga berpengaruh terhadap pressure coeficient pada boundary layer airfoil dan mengakibatkan blockage effect serta terjadinya vortex yang berbeda.

  6. The use of lithium clearance measurements as an estimate of glomerulo-tubular function.

    Science.gov (United States)

    Whiting, P H

    1999-01-01

    Lithium clearance measurements are based on the observation that lithium undergoes isoosmotic reabsorption in the proximal renal tubule to the same extent as salt and water, but undergoes neither reabsorption nor secretion elsewhere in the nephron. Consequently, lithium clearance values estimate the delivery of isoosmotic fluid to the loop of Henle and hence provide an assessment of proximal tubular reabsorption of isoosmotic fluid. If sodium clearance and urinary flow rate are also measured, then this allows the derivation of a number of parameters relating to both the absolute and relative renal handling of isoosmotic fluid in the proximal and distal regions of the kidney. Consequently, lithium clearance techniques can be used in both experimental and clinical studies to evaluate glomerulo-tubular function and provide information regarding the handling of sodium and water by the proximal and distal nephron in both health and disease. The use of lithium clearance measurements in the assessment of glomerulo-tubular function in patients treated with rIL2 for colorectal cancer is described and its application to both drug-induced toxicity and other disease states discussed.

  7. A model of metabolism and clearance of organic compounds from the respiratory tract

    International Nuclear Information System (INIS)

    In cases where inhalants induce toxicity in the airway epithelium, the mechanism of absorption is an important determinant of target dose. Absorption of organic solutes in the lungs occurs mainly by two consecutive mechanisms; molecular diffusion drives the chemicals into the tissues, and blood perfusion of the tissues removes the chemicals into the systemic circulation. Solutes having lipophilicities ranging from equally soluble in lipids and water to moderately more lipid-soluble are limited by the perfusion during clearance from the lungs. The perfusion-limited solute enters the blood circulation from all regions of the lungs within minutes and is distributed to other organs via the systemic circulation. In contrast, clearance of highly lipophilic toxicants, such as benzo(a)pyrene, from the lungs is diffusion-limited. The limiting process refers to the slowest transport mechanism of either perfusion or diffusion. Because of the short distance from the surface of the alveolar region to the capillary network, diffusion-limited clearance of highly lipophilic solutes occurs within minutes. In the thicker epithelium of the conducting airways, however, clearance may take hours. The purpose of the current modeling effort was to encompass both mechanisms of clearance in a single model in order to explore the influence of toxicant lipophilicity and local metabolism on the dosimetry at the airway portal-of-entry

  8. Effect of increases in lung volume on clearance of aerosolized solute from human lungs

    Energy Technology Data Exchange (ETDEWEB)

    Marks, J.D.; Luce, J.M.; Lazar, N.M.; Wu, J.N.; Lipavsky, A.; Murray, J.F.

    1985-10-01

    To study the effect of increases in lung volume on solute uptake, we measured clearance of /sup 99m/Tc-diethylenetriaminepentaacetic acid (Tc-DTPA) at different lung volumes in 19 healthy humans. Seven subjects inhaled aerosols (1 micron activity median aerodynamic diam) at ambient pressure; clearance and functional residual capacity (FRC) were measured at ambient pressure (control) and at increased lung volume produced by positive pressure (12 cmH2O continuous positive airway pressure (CPAP)) or negative pressure (voluntary breathing). Six different subjects inhaled aerosol at ambient pressure; clearance and FRC were measured at ambient pressure and CPAP of 6, 12, and 18 cmH2O pressure. Six additional subjects inhaled aerosol at ambient pressure or at CPAP of 12 cmH2O; clearance and FRC were determined at CPAP of 12 cmH2O. According to the results, Tc-DTPA clearance from human lungs is accelerated exponentially by increases in lung volume, this effect occurs whether lung volume is increased by positive or negative pressure breathing, and the effect is the same whether lung volume is increased during or after aerosol administration. The effect of lung volume must be recognized when interpreting the results of this method.

  9. HPV prophylactic vaccination in males improves the clearance of semen infection.

    Science.gov (United States)

    Foresta, Carlo; Garolla, Andrea; Parisi, Saverio; Ghezzi, Marco; Bertoldo, Alessandro; Di Nisio, Andrea; De Toni, Luca

    2015-10-01

    •We evaluated whether seroconversion in males influences HPV semen infection.•Naturally seroconverted patients showed reduced prevalence of HPV semen infection.•Naturally seroconverted patients also showed virtual absence of HPV multiple infection.•Prophylactic HPV vaccination induced clearance within 12 months from recruitment.•Seroconversion represents a key process involved in the clearance of the HPV.Available prophylactic vaccinations are considered of protective value for genital condyloma and precancerous lesions in female, but cost-effectiveness of the use of HPV vaccine in males is largely underinvestigated. HPV detection in semen is also an emerging problem in couples eligible for assisted reproduction techniques, since persistent infections are not compatible with repeated 6-months counselling-cycles to allow any spontaneous clearance of the virus in older infertile couples.In this study, we provide evidence that the development of seroconversion in human males affected by HPV infection in the genito-urinary tract, detected by HPV-DNA presence in the semen, has beneficial effects on the clearance of a viral load. Moreover, administration of prophylactic vaccination to HPV infected-seronegative patients induced seroconversion within 6 months from the first dosage administration, achieving 10 folds-higher antibody titre compared to natural seroconversion. If vaccine administration ameliorates the clearance of HPV semen infection, this could be a potential benefit to overcome fertility problems related to persistent HPV infections in males, after an obvious cost-effectiveness analysis.

  10. Effect of Inlet Clearance on the Aerodynamic Performance of a Centrifugal Blower

    Science.gov (United States)

    Hariharan, C.; Govardhan, M.

    2016-09-01

    The present work reports the effect of inlet clearance on the performance of a centrifugal blower, with parallel wall volute, over its full operating range. For a particular impeller configuration, four volutes based on constant angular momentum principle, have been designed and analysed numerically for varying inlet clearances ranging from 0 mm (ideal clearance) to 5 mm. The computational methodology is validated using experimental data. The results indicate that as the clearance increases, the impeller performance in terms of both static and total pressure rise deteriorate. Further, the stage performances deteriorate in terms of efficiency and specific work for all mass flow rates. However, the performance of volute improves at lower mass flow rates compared to the Best Efficiency Point (BEP). A set of correlations have been developed to predict the change in stage performance as a function of clearance ratio. The non-dimensional values of change in specific work, isentropic efficiency and static pressure are found to be same irrespective of the shape of the volute.

  11. Subcellular clearance and accumulation of Huntington disease protein: A mini-review

    Directory of Open Access Journals (Sweden)

    Ting eZhao

    2016-04-01

    Full Text Available Huntington’s disease (HD is an autosomal dominant, progressive neurodegenerative disease caused by an expanded polyglutamine (polyQ tract in the N-terminal region of mutant huntingtin (mHtt. As a result, mHtt forms aggregates that are abundant in the nuclei and processes of neuronal cells. Although the roles of mHtt aggregates are still debated, the formation of aggregates points to deficient clearance of mHtt in brain cells. Since the accumulation of mHtt is a prerequisite for its neurotoxicity, exploring the mechanisms for mHtt accumulation and clearance would advance our understanding of HD pathogenesis and help us develop treatments for HD. We know that the ubiquitin-proteasome system and autophagy play important roles in clearing mHtt; however, how mHtt preferentially accumulates in neuronal nuclei and processes remains unclear. Studying the clearance of mHtt in neuronal cells is a challenge because neurons are morphologically and functionally polarized, which means the turnover of mHtt may be distinct in different cellular compartments. In this review, we discuss our current knowledge about the clearance and accumulation of mHtt and strategies of examining mHtt clearance and accumulation in different subcellular regions

  12. Thickness and clearance visualization based on distance field of 3D objects

    Directory of Open Access Journals (Sweden)

    Masatomo Inui

    2015-07-01

    Full Text Available This paper proposes a novel method for visualizing the thickness and clearance of 3D objects in a polyhedral representation. The proposed method uses the distance field of the objects in the visualization. A parallel algorithm is developed for constructing the distance field of polyhedral objects using the GPU. The distance between a voxel and the surface polygons of the model is computed many times in the distance field construction. Similar sets of polygons are usually selected as close polygons for close voxels. By using this spatial coherence, a parallel algorithm is designed to compute the distances between a cluster of close voxels and the polygons selected by the culling operation so that the fast shared memory mechanism of the GPU can be fully utilized. The thickness/clearance of the objects is visualized by distributing points on the visible surfaces of the objects and painting them with a unique color corresponding to the thickness/clearance values at those points. A modified ray casting method is developed for computing the thickness/clearance using the distance field of the objects. A system based on these algorithms can compute the distance field of complex objects within a few minutes for most cases. After the distance field construction, thickness/clearance visualization at a near interactive rate is achieved.

  13. Measurement of cerebral blood flow in the pig by the Xe-133 clearance technique

    International Nuclear Information System (INIS)

    The Xe-133 clearance technique is used to measure cerebral blood flow in the pig, which often serves as an experimental animal for cardiovascular research. The clearance curves are fitted by a two-exponential model. However, the fitted parameters are incompatible with a two-compartmental model: the values found for the parameters depend on the length of the clearance curve analysed. The discrepancies are thought to be consequences of the heterogeneity of cerebral blood flow and of mathematical problems of parameter identification. The non-validity of the relative weight of the fast clearance component as an anatomical or functional parameter is demonstrated. The use of the mean time constant, mean transit time, mean decay constant and initial slope for determination of cerebral blood flow rates is discussed. The mean cerebral blood flow of the anaesthetized pig measured by the clearance technique is found to be lower than the blood flow measured by means of a flow probe around the common carotid artery (with the external carotid artery tied off). The existence of a significant arteriovenous shunt flow is postulated. (orig.)

  14. Dynamic responses of space solar arrays considering joint clearance and structural flexibility

    Directory of Open Access Journals (Sweden)

    Yuanyuan Li

    2016-06-01

    Full Text Available This article numerically investigates the effects of revolute joint clearance and structural flexibility on the overall dynamic characteristics of a deployable solar array system. Considering torque spring, close cable loop configuration, and lock mechanism, a typical mechanism composed of a main body with a yoke and two panels is used as a demonstration case to study the effects of clearance and flexibility on the dynamic response of the deployable solar array system in the deployment and lock process. The normal contact force model and tangential friction model in clearance joint are established using Lankarani Nikravesh model and modified Coulomb friction model, respectively. The numerical simulation results reveal that the coupling of clearance and flexibility makes different effects on the dynamic characteristics of the deployable space solar arrays for different operation stages. Besides, the clearance and flexibility of a mechanical system play crucial roles in predicting accurately the dynamic response of the system, which is the foundation of mechanism design, precision analysis, and control system design.

  15. Numerical Simulation of Tip Clearance Flow Passive Control in Axial Turbine

    Institute of Scientific and Technical Information of China (English)

    LI Wei; QIAO Wei-yang; XU Kai-fu; LUO Hua-ling

    2008-01-01

    This paper focuses on the effects of five different passive turbine tip clearance flow control methods on the tip clearance flow physics, which consists of a partial suction side squealer tip, a double squealer tip, a pressure side tip shelf with inclined squealer tip on a double squealer tip, a tip platform extension edge in pressure side and in suction side respectively. A pressure-correction based, 3D Reynolds-averaged Navier-Stokes equations CFD code with Reynolds Stress Model was adopted. The variable specific heat was considered. The detailed tip clearance flow field with different squealer rims was described with the streamline and the velocity vector. Accordingly, the mechanisms of five passive controls were elucidated; the effects of the passive controls on turbine efficiency and tip clearance flow field were illuminated. The results showed that the secondary flow loss near the outer casing including the tip leakage losses and the passage vortex losses could be reduced in all the five passive control methods. The turbine efficiency could be increased via the rational passive turbine tip clearance flow control. The Improved PS Squealer had the best effect on turbine efficiency, and the efficiency increased by 0.215%.

  16. 5-DOF Dynamic Model of Vehicle Shimmy System with Clearance at Universal Joint in Steering Handling Mechanism

    OpenAIRE

    Jianwei Lu; Yi Xu; Chen Hu; Vakakis, Alexander F.; Bergman, Lawrence A.

    2013-01-01

    5-DOF dynamic model of vehicle shimmy system with clearance in universal joint of steering handling mechanism is presented. The sub model of cross shaft universal joint with clearance is built based on Hertz' theory, and two-state model is applied to describe the contact force. The sub model of the universal joint is combined with the simplified dynamic model of steering system, and a 5-DOF dynamic model of vehicle shimmy system with consideration of assembling clearance in universal joint of...

  17. Effects and outcome of Tamsulosin more than just stone clearance after extracorporeal shock wave lithotripsy for renal calculi

    International Nuclear Information System (INIS)

    Objective: To determine the effect of Tamsulosin, as adjunctive medical therapy after Extracorporeal Shock Wave Lithotripsy for renal stones on rate of stone clearance, clearance time, pain intensity during stone clearance, steinstrasse formation and auxiliary surgical intervention required. Method: A prospective randomized controlled study was carried out in 120 patients who underwent ESWL for renal stones of 0.5-2.0 cm. They were randomized into study and control group in which Tamsulosin 0.4mg/day was given in former as an adjunctive medical therapy. All patients underwent ESWL every 2 weeks until complete stone clearance for 8 weeks. The parameters assessed were stone clearance, clearance time, pain intensity and effect on steinstrasse. Results: Of the 120 patients 60 were in each group. The stone clearance rate was greater in study than in control group, 58(96.7%) vs. 48(80%) respectively, (p<0.004). The mean stone clearance time was observed earlier in study group as compared to control group with significant statistical difference in stone size between 0.6-1.5 cm. The mean intensity of pain patients experienced according to Visual analogue scale (VAS) was significantly less in study group (p<0.002). The rate of steinstrasse formation was observed to be higher in control than in study group 15(25%) vs 6(10%) respectively(p<0.003), while its spontaneous clearance was higher in study group than in control group 83.3% vs 33.3% (p<0.03). Conclusion: Tamsulosin significantly increases stone clearance after shock wave lithotripsy for renal stones. It also appeared to facilitate earlier stone clearance, reduces severity of pain, reduces the incidence of steinstrasse formation and tends to facilitate its spontaneous clearance. (author)

  18. A parameters optimization method for planar joint clearance model and its application for dynamics simulation of reciprocating compressor

    Science.gov (United States)

    Hai-yang, Zhao; Min-qiang, Xu; Jin-dong, Wang; Yong-bo, Li

    2015-05-01

    In order to improve the accuracy of dynamics response simulation for mechanism with joint clearance, a parameter optimization method for planar joint clearance contact force model was presented in this paper, and the optimized parameters were applied to the dynamics response simulation for mechanism with oversized joint clearance fault. By studying the effect of increased clearance on the parameters of joint clearance contact force model, the relation of model parameters between different clearances was concluded. Then the dynamic equation of a two-stage reciprocating compressor with four joint clearances was developed using Lagrange method, and a multi-body dynamic model built in ADAMS software was used to solve this equation. To obtain a simulated dynamic response much closer to that of experimental tests, the parameters of joint clearance model, instead of using the designed values, were optimized by genetic algorithms approach. Finally, the optimized parameters were applied to simulate the dynamics response of model with oversized joint clearance fault according to the concluded parameter relation. The dynamics response of experimental test verified the effectiveness of this application.

  19. Viral clearance by flow-through mode ion exchange columns and membrane adsorbers.

    Science.gov (United States)

    Miesegaes, G R; Lute, S C; Read, E K; Brorson, K A

    2014-01-01

    Anion exchange (AEX) is a common downstream purification operation for biotechnology products manufactured in cell culture such as therapeutic monoclonal antibodies (mAbs) and Fc-fusion proteins. We present a head-to-head comparison of the viral clearance efficiency of AEX adsorbers and column chromatography using the same process fluids and comparable run conditions. We also present overall trends from the CDER viral clearance database. In our comparison of multiple brands of resins and adsorbers, clearance of three model viruses (PPV, X-MuLV, and PR772) was largely comparable, with some exceptions which may reflect run conditions that had not been optimized on a resin/membrane specific basis.

  20. Respiratory tract clearance model for dosimetry and bioassay of inhaled radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Bailey, M.R.; Birchall, A. (National Radiological Protection Board, Chilton (UK)); Cuddihy, R.G. (Inhalation Toxicology Research Inst., Albuquerque, NM (USA)); James, A.C. (Pacific Northwest Lab., Richland, WA (USA)); Roy, M. (CEA Centre d' Etudes Nucleaires de Fontenay-aux-Roses, 92 (France). Inst. de Protection et de Surete Nucleaire)

    1990-07-01

    The ICRP Task Group on Respiratory Tract Models is developing a model to describe the retention and clearance of deposited radionuclides for dose-intake calculations and interpretation of bioassay data. Clearance from each region is treated as competition between mechanical transport, which moves particles to the gastro-intestinal tract and lymph nodes, and the translocation of material to blood. It is assumed that mechanical transport rates are the same for all materials, and that rates of translocation to blood are the same in all regions. Time-dependent clearance is represented by combinations of compartments. Representative values of parameters to describe mechanical transport from the human respiratory tract have been estimated, and guidance is given on the determination of translocation rates. It is emphasized that the current version of the model described here is still provisional. 30 refs.

  1. Reverse lung clearance of Tc-99m DTPA induced by postural changes

    International Nuclear Information System (INIS)

    The lung clearance of Tc 99m DTPA is generally attributed to the degree of distension of the interepithelial junctions and thus of the alveoli. To assess this hypothesis a submicronic aerosol of Tc 99m DTPA (0.5 μ mass median diameter) was inhaled by eight non smoking volunteers placed in left lateral decubitus (LLD) where the alveoli of the left lung are compressed and those of the right lung expanded. The lung radioactivity was followed with a gamma camera 15 minutes in LLD, then 15 minutes in right lateral decubitus (RLD) to reverse the relative distension of the alveoli. Regional clearances were computed on each lung divided in three horizontal slices. These results suggest that alveolar distension has a major role in the DTPA clearance which is relatively independent of the initial deposition of the aerosol

  2. Effect of N-acetylcysteine in subjects with slow pulmonary mucociliary clearance.

    Science.gov (United States)

    Todisco, T; Polidori, R; Rossi, F; Iannacci, L; Bruni, B; Fedeli, L; Palumbo, R

    1985-01-01

    There is significant evidence that in the general population there are subjects either with fast or slow pulmonary mucociliary clearance rates. At the moment we do not know the physiological importance of such finding. Slow clearers should be regarded as a subpopulation at risk for bronchopulmonary diseases. Therefore, it would be of considerable interest if their mucociliary function could be stimulated by drugs for preventive purposes. Twelve apparently healthy subjects with slow mucociliary clearance rate, selected in an epidemiologic survey in a non-smokers population were given 0.6 g oral N-acetylcysteine/day/60 days in a double-blind cross-over randomized study. After treatment their mucociliary clearance rates increased by about 35% as compared with baseline values, and returned to pre-treatment values after the washout period. Subjects were unresponsive to placebo treatment. It would seem that slow clearers are protected against lung aggressions by prevention and/or mucus-active drugs.

  3. The Development and Implementation of the Kennedy Space Center Umbilical Clearance Tool

    Science.gov (United States)

    Chesnutt, David

    2016-01-01

    In preparation for NASAs upcoming Space Launch System program, the Kennedy Space Center is currently developing subsystems to provide fuel, purges and communications to the flight vehicle, known as umbilicals. It is vital to the crew and mission that these umbilicals release at T-0 without re-contacting the vehicle as it is accelerating from the launch pad. To help ensure this requirement is met by the program, a methodology of evaluating the moving bodies was developed and implemented into a tool using MATLAB. The tool, known as the KSC Umbilical Clearance Tool, takes a given elevation of interest and an umbilical retract profile within the plane to evaluate the clearance between the umbilical arm and thousands of independent flight vehicle drift profiles from a Monte Carlo analysis. The presentation will delve into the challenges associated with developing and implementing the tool framed in the context of evaluating the clearance for one of the SLS umbilicals.

  4. NONLINEAR DYNAMIC SIMULATION OF AN AXIALLY SLIDE-SPIN ROCKET FLEXIBLE SYSTEM WITH CLEARANCE

    Institute of Scientific and Technical Information of China (English)

    Zhu Huailiang; Zhang Fuxiang

    2005-01-01

    A hybrid approach is presented to investigate the dynamic behavior of an axially slide-spin flexible rocket with nonlinear clearance. The equations of motion of the flexible rocket are derived based upon Euler-Bernoulli beam theory and Hamilton principle and the finite element method. The characteristics of clearance between the spinning rocket and launcher are considered to be piecewise linear. Numerical solution is developed by direct integration method and demonstrates the validity of the method. The coupled dynamic behavior of axial motion and transverse vibrations of rocket are analyzed, and the influences of axially moving acceleration, spin speed, linking stiffness of elastic "shoes", and the nonlinearity of clearance on the motion attitude of rocket are studied.

  5. Radioactive waste management: Review on clearance levels and acceptance criteria legislation, requirements and standards

    International Nuclear Information System (INIS)

    In 2011 the joint research project Metrology for Radioactive Waste Management (MetroRWM) of the European Metrology Research Programme (EMRP) started with a total duration of three years. Within this project, new metrological resources for the assessment of radioactive waste, including their calibration with new reference materials traceable to national standards will be developed. This paper gives a review on national, European and international strategies as basis for science-based metrological requirements in clearance and acceptance of radioactive waste. - Highlights: • Legislation, requirements and standards in radioactive waste management. • Strategies and methods to maintain the relevant clearance levels and acceptance criteria. • International, European and national activity levels and limits for exemption and clearance of radioactive waste. • Requirements for acceptance for storage and final disposal of radioactive waste. • Metrological requirements for radioactive waste characterisation

  6. Pulmonary clearance rate of two chemically different forms of inhaled pertechnetate.

    Science.gov (United States)

    Walker, P S; Conway, J H; Fleming, J S; Bondesson, E; Borgström, L

    2001-01-01

    Attempts to image the pulmonary deposition site of radiolabeled aerosols delivered by dry powder inhalers (DPIs) and pressurized metered-dose inhalers (pMDIs) using single photon emission computed tomography (SPECT) have been limited by the rapid pulmonary clearance of radiolabel. To determine whether aqueous solubility of the radiolabel is a significant factor, the pulmonary clearance rates of two chemically different forms of 99mTc were calculated. A dry powder formulation of terbutaline sulphate was radiolabeled for inhalation by Turbuhaler (AstraZeneca) using the water-soluble salt sodium pertechnetate and the water-insoluble salt tetraphenylarsonium pertechnetate. A pilot study was conducted during which two control subjects each inhaled the two radiolabeled aerosols on separate days. Intrasubject clearance rates for the two species were very similar. It was therefore concluded that water insolubility of the pertechnetate salt alone was not enough to extend the lung residency time of the radiolabel. PMID:11681652

  7. Effect of blade tip configuration on tip clearance loss of a centrifugal impeller

    Science.gov (United States)

    Ishida, Masahiro; Ueki, Hironobu; Senoo, Yasutoshi

    1989-06-01

    The effect of blade tip configuration on the tip clearance loss was examined experimentally using an unshrouded centrifugal impeller with backward-leaning blades. Tips with rounded edges, sharp square edges, and edges with end plates were tested. The observed tip clearance effects could be theoretically predicted by assuming reasonable values of the contraction coefficent alpha = 0.91 for the round edge, 0.73 for the sharp square edge, and 0.53 for the end-plate edge. The impeller efficiency was improved by about 1.5 point by reducing the contraction coefficient from 0.91 to 0.53. The effect of contraction coefficient on impeller efficiency depends on the ratio of leakage loss to the tip clearance loss. Improved efficiency for impellers with highly loaded blades is expected from reducing the contraction coefficient.

  8. Optimization Based Clearance of Flight Control Laws A Civil Aircraft Application

    CERN Document Server

    Hansson, Anders; Puyou, Guilhem

    2012-01-01

    This book summarizes the main achievements of the EC funded 6th Framework Program project COFCLUO – Clearance of Flight Control Laws Using Optimization. This project successfully contributed to the achievement of a top-level objective to meet society’s needs for a more efficient, safer and environmentally friendly air transport by providing new techniques and tools for the clearance of flight control laws. This is an important part of the certification and qualification process of an aircraft – a costly and time-consuming process for the aeronautical industry.   The overall objective of the COFCLUO project was to develop and apply optimization techniques to the clearance of flight control laws in order to improve efficiency and reliability. In the book, the new techniques are explained and benchmarked against traditional techniques currently used by the industry. The new techniques build on mathematical criteria derived from the certification and qualification requirements together with suitable models...

  9. Long-term clearance of [57Co]cyanocobalamin in vegans and pernicious anaemia.

    Science.gov (United States)

    Amin, S; Spinks, T; Ranicar, A; Short, M D; Hoffbrand, A V

    1980-01-01

    1. Whole-body counting has been used to monitor the clearance of [57Co]cyanocobalamin in normal subjects, vegans and patients with pernicious anaemia. After oral administration of 57Co-labelled cyanocobalamin (1 microgram/1 muCi), subjects were counted for radioactivity monthly for a maximum period of 1 year. 2. The results obtained were consistent with a monoexponential clearance model and a least squares fit showed that there was no significant difference between the mean clearance rates for the vegans and normal subjects. 3. The patients with pernicious anaemia cleared the vitamin significantly more quickly than the normal control subjects. 4. This may be due to failure to reabsorb biliary vitamin B12 in pernicious anaemia because of the absence of intrinsic factor.

  10. Kinetics of the Clearance of Radioactive Colloids from Blood and the Physicochemical Characteristics of Their Morphology

    International Nuclear Information System (INIS)

    We are familiar with the differences to be found in the literature as regards the clearance of radioactive colloids from blood: in some cases clearance efficiency is equal to unity and hepatic flow can be measured with 131I-C. A., while in other cases the efficiency is highly variable and the flow cannot be measured externally with 198Au. The purpose of the present study was to obtain a better understanding of the differences that have been encountered in blood clearance of the following Saclay colloidal solutions: 198Au S2 and S3 solutions, which differ only in the dilution technique, technetium-99m T-cK1 and indium-113m InK1, For this purpose clearance curves were recorded in the same subject with different isotopes. Healthy subjects showed only slight differences, cirrhosis patients much larger ones. The authors have also attempted to relate the differences encountered to the physico-chemical characteristics of the morphology of the colloidal particles involved. For this purpose we used - apart from electron microscopy, which could not resolve the dimensions of the actual kinetic particle (including solvation) - techniques which caused a minimum of perturbation in the state of the product under study, such as optical methods of analysis. Lastly, an attempt has been made to investigate how one could use such clearance kinetics in routine functional studies while minimizing the influence of the nature of the product. For this purpose we have compared fractional clearance, already a standard technique, with the extra-hepatic fixation index which has been used at the Service Hospitalier Frédéric Joliot since 1966. (author)

  11. Immune modulation with sulfasalazine attenuates immunopathogenesis but enhances macrophage-mediated fungal clearance during Pneumocystis pneumonia.

    Directory of Open Access Journals (Sweden)

    Jing Wang

    Full Text Available Although T cells are critical for host defense against respiratory fungal infections, they also contribute to the immunopathogenesis of Pneumocystis pneumonia (PcP. However, the precise downstream effector mechanisms by which T cells mediate these diverse processes are undefined. In the current study the effects of immune modulation with sulfasalazine were evaluated in a mouse model of PcP-related Immune Reconstitution Inflammatory Syndrome (PcP-IRIS. Recovery of T cell-mediated immunity in Pneumocystis-infected immunodeficient mice restored host defense, but also initiated the marked pulmonary inflammation and severe pulmonary function deficits characteristic of IRIS. Sulfasalazine produced a profound attenuation of IRIS, with the unexpected consequence of accelerated fungal clearance. To determine whether macrophage phagocytosis is an effector mechanism of T cell-mediated Pneumocystis clearance and whether sulfasalazine enhances clearance by altering alveolar macrophage phagocytic activity, a novel multispectral imaging flow cytometer-based method was developed to quantify the phagocytosis of Pneumocystis in vivo. Following immune reconstitution, alveolar macrophages from PcP-IRIS mice exhibited a dramatic increase in their ability to actively phagocytose Pneumocystis. Increased phagocytosis correlated temporally with fungal clearance, and required the presence of CD4(+ T cells. Sulfasalazine accelerated the onset of the CD4(+ T cell-dependent alveolar macrophage phagocytic response in PcP-IRIS mice, resulting in enhanced fungal clearance. Furthermore, sulfasalazine promoted a TH2-polarized cytokine environment in the lung, and sulfasalazine-enhanced phagocytosis of Pneumocystis was associated with an alternatively activated alveolar macrophage phenotype. These results provide evidence that macrophage phagocytosis is an important in vivo effector mechanism for T cell-mediated Pneumocystis clearance, and that macrophage phenotype can be altered

  12. Comparative study of conventional PAH and inulin clearance and slope clearance of 131I-o-hippuric acid and 51Cr-EDTA

    International Nuclear Information System (INIS)

    ''Classic'' PAH and inulin clearance were determined in 81 patients with renal anomalies or renal diseases of different genesis and severity. In addition, radioisotope nephrography was carried out after administration of I-131-o-hippuric acid, followed by administration of Cr-51-EDTA. The activity decrease was recorded by a sensor located over the patient's right shoulder; the activities of a serum sample and of the urine excreted after 21 or 31 min were measured, and the findings were compared with those of the classic method. The clearance data calculated on the basis of the soulder measurements were hardly compatible with those of the conventional method in the case of 131I-o-hippuric acid (r=0.54) and totally incompatible in the case of 51Cr-EDTA. This means that the method described by Oberhausen is the only accurate method available for a quantitative assessment of the renal function on the basis of measurements of the activity decrease in the body. The activity of urine excreted after 31 min (131I-hippuric acid:r=0.992, 51Cr-EDTA:r=0.79) is a sufficiently accurate parameter although it is inaccurate at PAH clearance, values > 130 ml/min and inulin clearance values > 30 ml/min. Of the many parameters of radioisotope nephrogram curves, in the case of 131I-o-hippuric acid only the parameters related to the ascent between 48 and 120 sec or to the secant ascent yield sufficient quantitative information for certain functional regions (r=0.9 resp. r=0.93). In the case of 51Cr-EDTA, semiquantitative information on the renal function can be obtained by constructing secants on the nephrogram curves (r=0.7 resp. r=0.72). Here as in the case of 131I-hippuric acid, the contribution of each kidney can be determined individually from the functional analysis of both kidneys. (orig.)

  13. Robust Foot Clearance Estimation Based on the Integration of Foot-Mounted IMU Acceleration Data.

    Science.gov (United States)

    Benoussaad, Mourad; Sijobert, Benoît; Mombaur, Katja; Coste, Christine Azevedo

    2015-01-01

    This paper introduces a method for the robust estimation of foot clearance during walking, using a single inertial measurement unit (IMU) placed on the subject's foot. The proposed solution is based on double integration and drift cancellation of foot acceleration signals. The method is insensitive to misalignment of IMU axes with respect to foot axes. Details are provided regarding calibration and signal processing procedures. Experimental validation was performed on 10 healthy subjects under three walking conditions: normal, fast and with obstacles. Foot clearance estimation results were compared to measurements from an optical motion capture system. The mean error between them is significantly less than 15 % under the various walking conditions. PMID:26703622

  14. Application of the concepts of exclusion, exemption and clearance. Safety guide

    International Nuclear Information System (INIS)

    The objective of this Safety Guide is to provide guidance to national authorities, including regulatory bodies, and operating organizations on the application of the concepts of exclusion, exemption and clearance as established in the International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources (BSS). The Safety Guide includes specific values of activity concentration for both radionuclides of natural origin and those of artificial origin that may be used for bulk amounts of material for the purpose of applying exclusion or exemption. It also elaborates on the possible application of these values to clearance

  15. 51Cr-EDTA plasma clearance in severe renal failure determined by one plasma sample

    DEFF Research Database (Denmark)

    Kamper, A L; Nielsen, S L

    1989-01-01

    Two hundred and thirty-four measurements of standard 51Cr-EDTA plasma clearance were made in 50 patients with severe chronic renal failure. Based on these data two calculation methods were attempted using one plasma sample drawn 24 h after injection of 51Cr-EDTA. One of the methods used the 'one...... renal dysfunction (estimated clearance values below 21 ml/min) may be determined with adequate precision by one plasma sample drawn at 24 h after injection of the tracer without sampling at 5 h. This appears to be a very practical simplification....

  16. The choice of speed and clearance for RAS on 3D method

    Institute of Scientific and Technical Information of China (English)

    WANG Jian-fang; LI Ji-de; CAI Xin-gong

    2003-01-01

    In this paper, a 3D source distribution technique is used to calculate the coupled motions between two ships which advance in the wave with the same speed. The numerical results of coupled motions for a frigate and a supply ship have a good agreement with the experimental results. Based on the 3D coupled motions of two ships, a spectral analysis is employed to clearly observe the effect of speed, clearance and wave heading on the significant relative motion amplitude (SRMA) of two ships. The method presented in this paper will be helpful to select suitable clearance, speed and wave heading for underway replenishment at sea(RAS).

  17. Determination of renal clearances of amylase/creatinine with chromogenic and enzymatic methods.

    Science.gov (United States)

    Hohenwallner, W; Wimmer, E; Sommer, R

    1979-12-01

    Urinary amylase was estimated by chromogenic (amylochrome Roche) as well as enzymatic methods (SKI and Beckman: substrate starch and substrate maltotetraose respectively). Random and timed urines (24 hour collections) were analysed. Clearances of amylase gave different results dependent upon the amylase-test used and the glomerular filtration rate. Correlation between chromogenic and enzymatic methods (starch as substrate) was poor. The ratio of amylase and creatinine clearance was used to test different methods. Reference values for this ratio for the amylochrome method (N = 106) were 2.85 +/- 0.99% and for the Beckman-DS method (N = 60) 2.82 +/- 0.87%.

  18. Peripheral Amyloid-β Levels Regulate Amyloid-β Clearance from the Central Nervous System

    OpenAIRE

    Marques, Marcos A.; Kulstad, J. Jacob; Savard, Christopher E.; Green, Pattie S.; Lee, Sum P.; Craft, Suzanne; Watson, G. Stennis; Cook, David G.

    2009-01-01

    Amyloid-β (Aβ) is cleared from the brain by both proteolytic digestion and transport across the blood-brain-barrier into the peripheral circulatory system. To investigate the role peripheral Aβ levels play in regulating Aβ brain clearance, we measured the clearance of [125I]-Aβ-{1-40 injected into the brains of liver-ligated rats that allowed peripheral Aβ levels to be maintained at elevated levels for approximately one hour with/without a single peripheral bolus of unlabeled Aβ-{1-40. We fou...

  19. Mechanism of antibody-mediated viral clearance in immunotherapy of respiratory syncytial virus infection of cotton rats.

    OpenAIRE

    Prince, G A; Hemming, V G; Horswood, R L; Baron, P A; Murphy, B R; Chanock, R M

    1990-01-01

    Antibody-mediated clearance of respiratory syncytial virus from cotton rat pulmonary tissues occurs in the absence of complement and in the absence of the Fc portion of the immunoglobulin G molecule, suggesting that complement-independent, cell-independent neutralization is the major mechanism of clearance.

  20. DEVELOPMENT OF ANTI-PERSONNEL MINE CLEARANCE ROBOT WITH HIGH SERVICEABILITY AND MANOEUVRABILITY FOR DETECTION AND DISACTIVATION OF EXPLOSIVE OBJECTS

    Directory of Open Access Journals (Sweden)

    D. Mironov

    2012-01-01

    Full Text Available A team of the BNTU researchers has developed an anti-personnel mine clearance robot that makes it possible to detect, disactivate or transport explosive objects to safe places excluding any danger to  human life. Performance characteristics of the anti-personnel mine clearance robot  surpass foreign analogues. 

  1. Initial deposition and early clearance of inhaled 239Pu(NO3)4 aerosols in beagle dogs

    International Nuclear Information System (INIS)

    Data from exposures of 113 beagle dogs to 239Pu(NO3)4 aerosols were analyzed for effects of aerosol properties on deposition and early clearance. The percent of inhaled aerosols deposited was not significantly dependent on particle size or aerosol concentration. The early clearance rate was significantly slower at the highest exposure levels than at medium and low levels

  2. The influence of clearance on friction, lubrication and squeaking in large diameter metal-on-metal hip replacements.

    Science.gov (United States)

    Brockett, Claire L; Harper, Phil; Williams, Sophie; Isaac, Graham H; Dwyer-Joyce, Rob S; Jin, Zhongmin; Fisher, John

    2008-04-01

    Large diameter metal-on-metal bearings (MOM) are becoming increasingly popular, addressing the needs of young and more active patients. Clinical data has shown excellent short-to-mid-term results, though incidences of transient squeaking have been noted between implantation and up to 2 years post-operative. Geometric design features, such as clearance, have been significant in influencing the performance of the bearings. Sets of MOM bearings with different clearances were investigated in this study using a hip friction simulator to examine the influence of clearance on friction, lubrication and squeaking. The friction factor was found to be highest in the largest clearance bearings under all test conditions. The incidence of squeaking was also highest in the large clearance bearings, with all bearings in this group squeaking throughout the study. A very low incidence of squeaking was observed in the other two clearance groups. The measured lubricating film was found to be lowest in the large clearance bearings. This study suggests that increasing the bearing clearance results in reduced lubricant film thickness, increased friction and an increased incidence of squeaking.

  3. Some problems on measurements of low level activity close to clearance level in metal waste and the solutions

    CERN Document Server

    Hattori, T

    2002-01-01

    On March 1999, Nuclear Safety Commission reported clearance levels, which can classify solid wastes in decommissioning and operation as a non-radioactive material and also represented a basic concept on confirmation of the clearance level on July 2001. In this paper, some problem to confirm the radioactivity level of metal wastes are arranged and a solution is described. (author)

  4. The clearance concept with special reference to determination of glomerular filtration rate in patients with fluid retention

    DEFF Research Database (Denmark)

    Henriksen, Ulrik L; Henriksen, Jens H

    2014-01-01

    In subjects without fluid retention, the total plasma clearance of a renal filtration indicator (inulin, (99m) Tc-DTPA, (51) Cr-EDTA) is close to the urinary plasma clearance. Conversely, in patients with fluid retention (oedema, pleural effusions, ascites), there is a substantial discrepancy...

  5. 75 FR 62444 - 60-Day Notice of Proposed Information Collection: Form DS-3057, Medical Clearance Update, OMB...

    Science.gov (United States)

    2010-10-08

    ... OMB control number in the subject line of your message. Mail (paper, disk, or CD-ROM submissions): Department of State, Office of Medical Clearances, SA-15 Room 400, 1800 North Kent St., Rosslyn, VA. 22209... of Medical Clearances, SA-15 Room 400, 1800 North Kent St., Rosslyn, VA. 22209. FAX...

  6. Reduced IFNλ4 activity is associated with improved HCV clearance and reduced expression of interferon-stimulated genes

    DEFF Research Database (Denmark)

    Terczynska-Dyla, Ewa; Bibert, Stephanie; Duong, Francois H T;

    2014-01-01

    Hepatitis C virus (HCV) infections are the major cause of chronic liver disease, cirrhosis and hepatocellular carcinoma worldwide. Both spontaneous and treatment-induced clearance of HCV depend on genetic variation within the interferon-lambda locus, but until now no clear causal relationship has...... of poor HCV clearance....

  7. Liver volume, portal vein flow, and clearance of indocyanine green and antipyrine in hyperthyroidism before and after antithyroid treatment

    DEFF Research Database (Denmark)

    Andersen, Vibeke; Sonne, J; Court-Payen, M;

    1999-01-01

    The aim of the study was to examine liver volume, portal vein flow, and indocyanine green (ICG) and antipyrine clearance in hyperthyroidism before and after antithyroid drug treatment.......The aim of the study was to examine liver volume, portal vein flow, and indocyanine green (ICG) and antipyrine clearance in hyperthyroidism before and after antithyroid drug treatment....

  8. Itch and scratching as predictors of time to clearance of psoriasis with narrow-band ultraviolet B therapy.

    NARCIS (Netherlands)

    Evers, A.W.M.; Kleinpenning, M.M.; Smits, T.; Boezeman, J.B.M.; Kerkhof, P.C.M. van de; Kraaimaat, F.W.; Gerritsen, M.J.P.

    2009-01-01

    BACKGROUND: Narrow-band ultraviolet (UV) B phototherapy is an effective treatment for psoriasis. However, there is considerable variability in the number of treatment sessions needed to achieve psoriasis clearance. While several clinical and treatment-related factors predict time to clearance, the e

  9. 77 FR 34391 - Submission for OMB Review; Comment Request Generic Clearance to Conduct Voluntary Customer...

    Science.gov (United States)

    2012-06-11

    ... HUMAN SERVICES National Institutes of Health Submission for OMB Review; Comment Request Generic... Collection: Title: Generic Clearance to Conduct Voluntary Customer/Partner Surveys; Type of Information... delivering information to the public. An essential strategy in accomplishing reinvention goals is the...

  10. Evaluation of a Microwave Blade Tip Clearance Sensor for Propulsion Health Monitoring

    Science.gov (United States)

    Woike, Mark R.

    2013-01-01

    The NASA Glenn Research Center has investigated a microwave blade tip clearance system for the structural health monitoring of gas turbine engines. This presentation describes the sensors and the experiments that have been conducted to evaluate their performance along with future plans for their use on an engine ground test.

  11. Allometric Scaling of Clearance in Paediatric Patients : When Does the Magic of 0.75 Fade?

    NARCIS (Netherlands)

    Calvier, E.A.M.; Krekels, E.H.J.; Välitalo, P.A.J.; Rostami-Hodjegan, A.; Tibboel, D.; Danhof, M.; Knibbe, C.A.J.

    2016-01-01

    Allometric scaling on the basis of bodyweight raised to the power of 0.75 (AS0.75) is frequently used to scale size-related changes in plasma clearance (CLp) from adults to children. A systematic assessment of its applicability is undertaken for scenarios considering size-related changes with and wi

  12. Coca and Colonists: Quantifying and Explaining Forest Clearance under Coca and Anti-Narcotics Policy Regimes

    Directory of Open Access Journals (Sweden)

    Andrew C. Millington

    2008-06-01

    Full Text Available The impacts of coca cultivation and coca eradication on rates of humid tropical forest clearance were examined in the agricultural colonization zone of Chapare, Bolivia. Using satellite image-derived land-use maps, interviews with farmers, and analyses of economic data and policy documents, forest clearance rates were analyzed in three contrasting communities from 1963 to 2003. Deforestation rates were very low from the late 1970s to the early 1990s when coca cultivation was widespread and anti-coca policies were weakly enforced. Before and after this period, deforestation rates were significantly higher. This study provides the first detailed quantitative analysis of deforestation rates under different policy regimes in a coca source region. It provides weak support for the argument that labor constraints lead to a reduction in forest clearance rates during periods of coca cultivation advanced by Kaimowitz (1997; but stronger support for Henkel's (1995 hypothesis that farmers would clear large areas of forest after abandoning coca to maintain household incomes. However, economic arguments based on household data alone are inadequate in explaining forest clearance in this region, and a political ecological approach that analyses economic drivers in a policy framework provides better explains deforestation dynamics.

  13. CD8+ T cells induce platelet clearance in the liver via platelet desialylation in immune thrombocytopenia

    Science.gov (United States)

    Qiu, Jihua; Liu, Xuena; Li, Xiaoqing; Zhang, Xu; Han, Panpan; Zhou, Hai; Shao, Linlin; Hou, Yu; Min, Yanan; Kong, Zhangyuan; Wang, Yawen; Wei, Yu; Liu, Xinguang; Ni, Heyu; Peng, Jun; Hou, Ming

    2016-01-01

    In addition to antiplatelet autoantibodies, CD8+ cytotoxic T lymphocytes (CTLs) play an important role in the increased platelet destruction in immune thrombocytopenia (ITP). Recent studies have highlighted that platelet desialylation leads to platelet clearance via hepatocyte asialoglycoprotein receptors (ASGPRs). Whether CD8+ T cells induce platelet desialylation in ITP remains unclear. Here, we investigated the cytotoxicity of CD8+ T cells towards platelets and platelet desialylation in ITP. We found that the desialylation of fresh platelets was significantly higher in ITP patients with positive cytotoxicity of CD8+ T cells than those without cytotoxicity and controls. In vitro, CD8+ T cells from ITP patients with positive cytotoxicity induced significant platelet desialylation, neuraminidase-1 expression on the platelet surface, and platelet phagocytosis by hepatocytes. To study platelet survival and clearance in vivo, CD61 knockout mice were immunized and their CD8+ splenocytes were used. Platelets co-cultured with these CD8+ splenocytes demonstrated decreased survival in the circulation and increased phagocytosis in the liver. Both neuraminidase inhibitor and ASGPRs competitor significantly improved platelet survival and abrogated platelet clearance caused by CD8+ splenocytes. These findings suggest that CD8+ T cells induce platelet desialylation and platelet clearance in the liver in ITP, which may be a novel mechanism of ITP. PMID:27321376

  14. Effect of esophageal emptying and saliva on clearance of acid from the esophagus

    International Nuclear Information System (INIS)

    The clearance of acid from the esophagus and esophageal emptying in normal subjects was studied. A 15-ml bolus of 0.1 N hydrochloric acid (pH 1.2) radiolabeled with [/sup 99m/Tc]sulfur colloid was injected into the esophagus, and the subject swallowed every 30 seconds. Concurrent manometry and radionuclide imaging showed nearly complete emptying of acid from the esophagus by an immediate secondary peristaltic sequence, although esophageal pH did not rise until the first swallow 30 seconds later. Esophageal pH then returned to normal by a series of step increases, each associated with a swallow-induced peristaltic sequence. Saliva stimulation by an oral lozenge shortened the time required for acid clearance, whereas aspiration of saliva from the mouth abolished acid clearance. Saliva stimulation or aspiration did not affect the virtually complete emptying of acid volume by the initial peristaltic sequence. It was concluded that esophageal acid clearance normally occurs as a two-step process: (1) Virtually all acid volume is emptied from the esophagus by one or two peristaltic sequences, leaving a minimal residual amount that sustains a low pH, and (2) residual acid is neutralized by swallowed saliva

  15. Mucociliary clearance in the rat lung and the effect of age

    International Nuclear Information System (INIS)

    Mucociliary clearance rate was measured in groups of rats (n = 25) at 2, 5, 8 and 12 months of age. Animals inhaled an aerosol of indium-111 labeled iron oxide particles (median dia. 1.95 u) for a period of 5 min. and thoracic activity was monitored externally during the next 48 hours. Clearance curves, generated as loss of initial activity versus time, were found to be biphasic and represented the sum of 2 exponential curves with separate rate constants (slopes). The first phase lasted 6 +/- 1.5 hours whereas the second was much slower and continued into the second day. Comparison of individual values obtained for the first phase at 2 months showed considerable variation among animals ranging +/- 20% from the mean. These variations were not due to experimental error or sex and persisted in each animal with aging. Absolute clearance rates, however, progressively decreased with age. This phenomenon was at least in part the result of a greater penetration of aerosol within the airways as the animal ages. Percent of initial radioactivity remaining within the lungs 48 hours following aerosol inhalation was 15.1 +/- 0.82% at 2 months and progressively increased to 28.4 + 0.60% at 12 months. The authors conclude that in rats mucociliary clearance is in part genetically determined and regional deposition patterns of particulates within the airways varies with age

  16. Clinical assessment of tumor clearance during radiotherapy as a prognostic factor of early glottic carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, Takehiro (Osaka Teishin Hospital (Japan). Dept. of Radiology); Inoue, T.; Ikeda, H. (Osaka Univ. Medical School (Japan). Dept. of Radiation Oncology); Teshima, T.; Murayama, S. (Osaka Univ. Medical School (Japan). Dept. of Radiology)

    1992-10-01

    From 1967 through 1985, 358 cases of early glottic carcinoma were treated with telecobalt therapy at the Department of Radiology, Osaka University Medical School. Among 278 cases treated with 2 Gy a day, the tumor response of 262 cases at 40, 50 and 60 Gy were evaluated by direct or indirect laryngoscope. The five-year local control rates of these evaluable cases of T1 and T2 glottic carcinoma were 79% and 70%, respectively. The local control rates of T1 glottic carcinoma with tumor clearance and persistence at 40 Gy were 83% (119/143) and 64% (43/67), and those of T2 cases were 86% (18/21) and 58% (18/31), respectively. The local control rates of the cases with tumor clearance and persistence at 40 Gy were same between T1 and T2 cases. The tumor clearance rates of T1 cases were significantly higher than those of T2 cases (p<0.005). T2 glottic carcinoma had larger tumor volumes and slower tumor regression and resulted in lower control rates compared with T1 glottic carcinoma. The difference in the radiation dose of T1 and T2 glottic carcinoma with the same clearance rate was estimated as 15 Gy using logit analysis. (orig.).

  17. 77 FR 43228 - Agency Information Collection Activities; Proposed Collection; Comment Request-Generic Clearance...

    Science.gov (United States)

    2012-07-24

    ... food and human nutrition research and extension program, including the development of techniques to...--Generic Clearance for the Development of Nutrition Education Messages and Products for the General Public AGENCY: Center for Nutrition Policy and Promotion, USDA. ACTION: Notice. SUMMARY: In accordance with...

  18. Whole body and regional clearances of noradrenaline and adrenaline in man

    DEFF Research Database (Denmark)

    Christensen, N J; Galbo, H; Gjerris, Anne Cathrine Roslev;

    1984-01-01

    The whole body clearance of noradrenaline (NA) was measured in seven patients pre- and postoperatively. L-3H-NA was infused intravenously for 90 min and steady-state concentrations of L-3H-NA were measured in both arterial and peripheral venous blood. Preoperatively, in the resting supine position...

  19. CD8(+) T cells induce platelet clearance in the liver via platelet desialylation in immune thrombocytopenia.

    Science.gov (United States)

    Qiu, Jihua; Liu, Xuena; Li, Xiaoqing; Zhang, Xu; Han, Panpan; Zhou, Hai; Shao, Linlin; Hou, Yu; Min, Yanan; Kong, Zhangyuan; Wang, Yawen; Wei, Yu; Liu, Xinguang; Ni, Heyu; Peng, Jun; Hou, Ming

    2016-01-01

    In addition to antiplatelet autoantibodies, CD8(+) cytotoxic T lymphocytes (CTLs) play an important role in the increased platelet destruction in immune thrombocytopenia (ITP). Recent studies have highlighted that platelet desialylation leads to platelet clearance via hepatocyte asialoglycoprotein receptors (ASGPRs). Whether CD8(+) T cells induce platelet desialylation in ITP remains unclear. Here, we investigated the cytotoxicity of CD8(+) T cells towards platelets and platelet desialylation in ITP. We found that the desialylation of fresh platelets was significantly higher in ITP patients with positive cytotoxicity of CD8(+) T cells than those without cytotoxicity and controls. In vitro, CD8(+) T cells from ITP patients with positive cytotoxicity induced significant platelet desialylation, neuraminidase-1 expression on the platelet surface, and platelet phagocytosis by hepatocytes. To study platelet survival and clearance in vivo, CD61 knockout mice were immunized and their CD8(+) splenocytes were used. Platelets co-cultured with these CD8(+) splenocytes demonstrated decreased survival in the circulation and increased phagocytosis in the liver. Both neuraminidase inhibitor and ASGPRs competitor significantly improved platelet survival and abrogated platelet clearance caused by CD8(+) splenocytes. These findings suggest that CD8(+) T cells induce platelet desialylation and platelet clearance in the liver in ITP, which may be a novel mechanism of ITP. PMID:27321376

  20. Reprocessed uranium influence on clearance application in uranium fuel fabrication plant

    International Nuclear Information System (INIS)

    Clearance levels for uranium isotopes have been recently authorized in Japan. The measurement of those elements can be disregarded when the nominal of the element (D/C), expressed as (D/C)*, is less than 10-3, where D is the specific radioactivity concentration of nuclides, C is the clearance level of nuclides, and (D/C)* is defined as (D/C) divided by the highest value of (D/C)'s in the element constitutions of uranium waste. In this study, the concentration of nuclides in reprocessed uranium was evaluated using ORIGEN2 burnup analyses and the most appropriate decontamination factors for determining the (D/C)* values and their influence on clearance application in the uranium fuel fabrication plant. It was concluded that nuclides other than five isotopes, 232U, 234U, 235U, 236U, and 238U, can be disregarded with regards to clearance application in the uranium fabrication plant, regardless of operation conditions, whether the fuel is fabricated by receiving reprocessed uranium or not. (author)

  1. 19 CFR 10.41b - Clearance of serially numbered substantial holders or outer containers.

    Science.gov (United States)

    2010-04-01

    ... such requirement pursuant to an application approved under 19 CFR 10.41b(b).” Also, pallets and other... the admissibility of such devices as regards plant pest risk, as provided for in 7 CFR 319.40-3. (1... 19 Customs Duties 1 2010-04-01 2010-04-01 false Clearance of serially numbered substantial...

  2. Dual roles for hepatic lectin receptors in the clearance of chilled platelets

    DEFF Research Database (Denmark)

    Rumjantseva, Viktoria; Grewal, Prabhjit K; Wandall, Hans H;

    2009-01-01

    Rapid chilling causes glycoprotein-Ib (GPIb) receptors to cluster on blood platelets. Hepatic macrophage beta(2) integrin binding to beta-N-acetylglucosamine (beta-GlcNAc) residues in the clusters leads to rapid clearance of acutely chilled platelets after transfusion. Although capping the beta-G...

  3. Effect of raised thoracic pressure and volume on 99mTc-DTPA clearance in humans

    Energy Technology Data Exchange (ETDEWEB)

    Nolop, K.B.; Maxwell, D.L.; Royston, D.; Hughes, J.M.

    1986-05-01

    Although positive airway pressure is often used to treat acute pulmonary edema, the effects on epithelial solute flux are not well known. We measured independently the effect of 1) positive pressure and 2) voluntary hyperinflation on the clearance of inhaled technetium-99m-labeled diethylenetriaminepentaacetic acid (/sup 99m/Tc-DTPA) in six nonsmokers and six smokers. Lung volumes were monitored by inductance plethysmography. Each subject was studied in four situations: 1) low end-expiratory volume (LO-), 2) low volume plus 9 cmH2O continuous positive airway pressure (LO+), 3) high end-expiratory volume (HI-), and 4) high volume plus continuous positive airway pressure (HI+). The clearance half time of 99mTc-DTPA for the nonsmokers decreased from 64.8 +/- 7.0 min (mean +/- SE) at LO- to 23.2 +/- 5.3 min at HI- (P less than 0.05). Positive pressure had no synergistic effect. The mean clearance half time for the smokers was faster than nonsmokers at base line but unaffected by similar changes in thoracic volume and pressure. We conclude that, in nonsmokers, positive airway pressure increases /sup 99m/Tc-DTPA clearance primarily through an increase in lung volume and that smokers are immune to these effects.

  4. Site of deposition and factors affecting clearance of aerosolized solute from canine lungs

    International Nuclear Information System (INIS)

    The influence of several factors on lung solute clearance using aerosolized /sup 99m/Tc-diethylenetriaminepentaacetate was determined. The authors used a jet nebulizer-plate separator-balloon system to generate particles with an activity median aerodynamic diameter of 1.1 μm, administered the aerosol in a standard fashion, and determined clearance half times (t/sub 1/2/) with a gamma-scintillation camera. The following serial studies were performed in five anesthetized, paralyzed, intubated, mechanically ventilated dogs: (1) control, with ventilatory frequency (f) = 15 breaths/min and tidal volume (V/sub T/) = 15 ml/kg during solute clearance; (2) repeat control, for reproducibility; (3) increased frequency, with f = 25 breaths/min and V/sub T/ = 10 ml/kg; (4) positive end-expiratory pressure (PEEP) of 10 cmH2O; (5) unilateral pulmonary arterial occlusion (PAO); and (6) bronchial arterial occlusion (BAO). Control t/sub 1/2/ was 25 +/- 5 min and did not change in the repeat control, increased frequency, or BAO experiments. PEEP markedly decreased t/sub 1/2/ to 13 +/- 3 min (P < 0.01), and PAO increased it to 37 +/- 6 min (P < 0.05). We conclude that clearance from the lungs by our method is uninfluenced by increased frequency, increases markedly with PEEP, and depends on pulmonary, not bronchial, blood flow

  5. Megalin and cubilin are endocytic receptors involved in renal clearance of hemoglobin

    DEFF Research Database (Denmark)

    Gburek, Jakub; Verroust, Pierre J; Willnow, Thomas E;

    2002-01-01

    The kidney is the main site of hemoglobin clearance and degradation in conditions of severe hemolysis. Herein it is reported that megalin and cubilin, two epithelial endocytic receptors, mediate the uptake of hemoglobin in renal proximal tubules. Both receptors were purified by use of hemoglobin-...

  6. 78 FR 23743 - Proposed Information Collection; Comment Request; Generic Clearance for Questionnaire Pretesting...

    Science.gov (United States)

    2013-04-22

    ... Questionnaire Pretesting Research AGENCY: Census Bureau, Commerce. ACTION: Notice. SUMMARY: The Department of... of small-scale questionnaire pretesting activities under this generic clearance. A block of hours... research program will be used by the Census Bureau and survey sponsors to improve questionnaires...

  7. 75 FR 16737 - Proposed Information Collection; Comment Request; Generic Clearance for Questionnaire Pretesting...

    Science.gov (United States)

    2010-04-02

    ... Questionnaire Pretesting Research AGENCY: U.S. Census Bureau. ACTION: Notice. SUMMARY: The Department of...-scale questionnaire pretesting activities under this generic clearance. A block of hours will be... will be used by the Census Bureau and survey sponsors to improve questionnaires and procedures,...

  8. Effects of hyperventilation and hypocapnic/normocapnic hypoxemia on renal function and lithium clearance in humans

    DEFF Research Database (Denmark)

    Christensen, H; Klausen, T; Fogh-Andersen, N;

    1998-01-01

    Using the renal clearance of lithium as an index of proximal tubular outflow, this study tested the hypothesis that acute hypocapnic hypoxemia decreases proximal tubular reabsorption to the same extent as hypocapnic normoxemia (hyperventilation) and that this response is blunted during normocapnic...

  9. Measurement of glomerular filtration rate in adults: accuracy of five single-sample plasma clearance methods

    DEFF Research Database (Denmark)

    Rehling, M; Rabøl, A

    1989-01-01

    After an intravenous injection of a tracer that is removed from the body solely by filtration in the kidneys, the glomerular filtration rate (GFR) can be determined from its plasma clearance. The method requires a great number of blood samples but collection of urine is not needed. In the present...

  10. 77 FR 1697 - Agency Information Collection Activities: Fast Track Generic Clearance for the Collection of...

    Science.gov (United States)

    2012-01-11

    ... on Agency Service Delivery: IHS Web site Customer Service Satisfaction Survey. Abstract: The... response Total hours respondents respondent (in hours) \\2\\ Web site Customer satisfaction survey (web- 500... Clearance for the Collection of Qualitative Feedback on Agency Service Delivery: IHS Web Site...

  11. Analysis of grease contamination influence on the internal radial clearance of ball bearings by thermographic inspection

    Directory of Open Access Journals (Sweden)

    Mišković Žarko Z.

    2016-01-01

    Full Text Available One of the most important factors influencing ball bearings service life is its internal radial clearance. However, this parameter is also very complex because it depends on applied radial load and ball bearings dimensions, surface finish and manufacturing materials. Thermal condition of ball bearings also significantly affects internal radial clearance. Despite many researches performed in order to find out relevant facts about different aspects of ball bearings thermal behaviour, only few of them are dealing with the real working conditions, where high concentration of solid contaminant particles is present. That’s why the main goal of research presented in this paper was to establish statistically significant correlation between ball bearings temperatures, their working time and concentration of contaminant particles in their grease. Because of especially difficult working conditions, the typical conveyor idlers bearings were selected as representative test samples and appropriate solid particles from open pit coal mines were used as artificial contaminants. Applied experimental methodology included thermographic inspection, as well as usage of custom designed test rig for ball bearings service life testing. Finally, by obtained experimental data processing in advanced software, statistically significant mathematical correlation between mentioned bearings characteristics was determined and applied in commonly used internal radial clearance equation. That is the most important contribution of performed research - the new equation and methodology for ball bearings internal clearance determination which could be used for eventual improvement of existing bearings service life equations. [Projekat Ministarstva nauke Republike Srbije, br. TR35029 i br. TR14033

  12. Clearance and binding of radiolabeled glycoproteins by cells of the murine mononuclear phagocyte system

    International Nuclear Information System (INIS)

    The clearance and binding of radiolabeled lactoferrin and fast α2-macroglobulin were studied. Both glycoproteins cleared rapidly following intravenous injection in mice, and both bound specifically to discrete receptors on murine peritoneal macrophages. The simultaneous presence of excess, unlabeled ligands specific for receptors recognizing terminal fucose, mannose, N-acetylglucosamine or galactose residues did not inhibit the clearance or binding of either lactoferrin or fast-α2M. The clearance and binding of enzymatically defucosylated lactoferrin was indistinguishable from native lactoferrin, indicating that terminal α(1-3)-linked fucose on lactoferrin is not necessary for receptor recognition. The clearance and binding of two fast -α2M forms, α2M-trypsin and α2M-MeNH2 cross compete with each other. Saturation binding studies indicated that the total binding of mannosyl -BSA, fusocyl-BSA, and N-acetylglucosaminyl-BSA to macrophages activated by BCG was approximately 15% of the levels observed with inflammatory macrophages elicited by thioglycollate broth. Cross-competition binding studies demonstrated a common surface receptor mediated binding of all three neoglycoprotein ligands and was identical to the receptor on mononuclear phagocytes that binds mannosyl- and N-acetylglucosaminyl-terminated glycoproteins. These results suggest that difference between discrete states of macrophage function may be correlated with selective changes in levels of the surface receptor for mannose-containing glycoproteins

  13. 78 FR 37783 - Proposed Information Collection; Comment Request; Generic Clearance for Internet Nonprobability...

    Science.gov (United States)

    2013-06-24

    .... Bureau of the Census Proposed Information Collection; Comment Request; Generic Clearance for Internet... the Internet at jjessup@doc.gov ). FOR FURTHER INFORMATION CONTACT: Requests for additional...-4827 (or via the Internet at jennifer.hunter.childs@ census.gov ). SUPPLEMENTARY INFORMATION:...

  14. 75 FR 68829 - Agency Information Collection Activities: Comment Request; Generic Survey Clearance for the...

    Science.gov (United States)

    2010-11-09

    ... of Education and Human Resources (EHR) AGENCY: National Science Foundation. ACTION: Notice. SUMMARY... INFORMATION: Title of Collection: EHR Generic Clearance. OMB Approval Number: 3145-0136. Expiration Date of.... The Directorate for Education and Human Resources (EHR), a unit within NSF, promotes rigor...

  15. Time-dependent clearance of mycophenolic acid in renal transplant recipients

    NARCIS (Netherlands)

    R.M. van Hest (Reinier); T. van Gelder (Teun); R. Bouw (René); T. Goggin (Timothy); R. Gordon (Robert); R. Mamelok (Richard); R.A. Mathot (Ron)

    2007-01-01

    textabstractAims: Pharmacokinetic studies of the immunosuppressive compound mycophenolic acid (MPA) have shown a structural decrease in clearance (CL) over time after renal transplantation. The aim of this study was to characterize the time-dependent CL of MPA by means of a population pharmacokineti

  16. Association of Continuous-Equivalent Urea Clearances with Death Risk in Intermittent Hemodialysis

    Directory of Open Access Journals (Sweden)

    Aarne Vartia

    2016-01-01

    Full Text Available Background. Several reports describe favorable results from frequent hemodialysis, but due to the lack of unequivocal dose measures it is not clear whether the benefits are due to more efficient toxin removal or other factors. Methods. The associations with death risk of six continuous-equivalent urea clearance measures were compared in 57 conventional in-center hemodialysis treatment periods of 51 patients, together 114 patient years. The double pool dose measures were calculated with the Solute-Solver program and separately scaled to urea distribution volume or normalized with body surface area. Results. Mortality associated significantly with equivalent renal urea clearance (EKR scaled to urea distribution volume (V (p=0.033 and with EKR normalized with body surface area (BSA (p=0.044 but not with V-scaled (p=0.059 nor BSA-normalized (p=0.183 standard clearance (stdK. Women had significantly higher normalized protein catabolic rate (nPCR, EKR/V, and stdK/V than men but slightly lower BSA-normalized dose measures and lower mortality. Protein catabolic rate and dialysis dose correlated positively with each other and with survival. Conclusions. The prognostically most valid continuous-equivalent clearance in the present material was EKR/V, calculated from double pool urea generation rate, distribution volume, and time-averaged concentration.

  17. E-Reserves Permissions and the Copyright Clearance Center: Process, Efficiency, and Cost

    Science.gov (United States)

    Holobar, J. Christopher; Marshall, Andrew

    2011-01-01

    This study examines the process of requesting copyright permissions through the Copyright Clearance Center's (CCC) pay-per-use service for electronic course reserves at the Penn State University Libraries in 2008. The authors investigate the efficiency of this process as a function of the percentage of permission requests successfully mediated by…

  18. Effectively Managing Copyright Clearance: Electronic Reserves in a Large Distance Education University

    Science.gov (United States)

    Wang, Yu-Hsiu; Baker, Megan

    2013-01-01

    This paper describes the automated copyright clearance process for electronic reserves materials by the electronic reserves staff at the Information and Library Services (ILS), at the University of Maryland University College (UMUC). Besides the standard practice to handle and post required course readings in digital format for UMUC's…

  19. Formation, Clearance and Mouthfeel Perception of Oral Coatings Formed by Emulsion-Filled Gels

    NARCIS (Netherlands)

    Camacho, Sara; Liu, Kun; Linden, Van Der Anoek; Stieger, Markus; De Velde, Van Fred

    2015-01-01

    Four emulsion-filled gelatin gels varying in fat content (5 and 15%) and type of emulsifier (whey protein isolate: fat droplets bound to matrix; Tween 20: fat droplets unbound to matrix) were studied. We investigated (1) the formation and clearance dynamics of fat deposition on the tongue using in v

  20. Antipyrine, oxazepam, and indocyanine green clearance in patients with chronic pancreatitis and healthy subjects

    DEFF Research Database (Denmark)

    Andersen, Vibeke; Sonne, J; Larsen, S

    1999-01-01

    Hepatic drug metabolism was examined in patients with chronic pancreatitis and healthy controls by using a cocktail design with three different model compounds: antipyrine to express phase-I oxidation, oxazepam to express phase-II conjugation, and indocyanine green (ICG), a high-clearance compound....

  1. Chronic Liver Disease Impairs Bacterial Clearance in a Human Model of Induced Bacteremia

    OpenAIRE

    Ashare, Alix; Stanford, Clark; Hancock, Patricia; Stark, Donna; Lilli, Kathleen; Birrer, Emily; Nymon, Amanda; Doerschug, Kevin C.; Hunninghake, Gary W.

    2009-01-01

    Sepsis often causes impaired hepatic function. Patients with liver disease have an increased risk of bacteremia. This is thought to be secondary to impaired reticuloendothelial system function. However, this has not been demonstrated clinically. Since transient bacteremia occurs following toothbrushing, we hypothesized that subjects with cirrhosis would have impaired bacterial clearance following toothbrushing compared with subjects with pulmonary disease and healthy controls. After baseline ...

  2. Method and system for measuring gate valve clearances and seating force

    Science.gov (United States)

    Casada, Donald A.; Haynes, Howard D.; Moyers, John C.; Stewart, Brian K.

    1996-01-01

    Valve clearances and seating force, as well as other valve operational parameters, are determined by measuring valve stem rotation during opening and closing operations of a translatable gate valve. The magnitude of the stem rotation, and the relative difference between the stem rotation on opening and closing provides valuable data on the valve internals in a non-intrusive manner.

  3. 77 FR 14807 - Emergency Clearance: Public Information Collection Requirements Submitted to the Office of...

    Science.gov (United States)

    2012-03-13

    ... section 1862(a)(1)(A) of the Social Security Act. We cannot reasonably comply with the normal clearance...: Private Sector (Business or other for-profit and Not-for-profit institutions); Number of Respondents: 2....gov/PaperworkReductionActof1995/PRAL/list.asp or Email your request, including your address,...

  4. [Evaluation of the renal function in type 2 diabetes: clearance calculation or cystatin C?].

    Science.gov (United States)

    Dhia, Rym Ben; Hellara, Ilhem; Harzallah, Olfa; Neffati, Fadoua; Khochtali, Ines; Mahjoub, Sylvia; Najjar, Mohamed Fadhel

    2012-01-01

    Screening for diabetic nephropathy is usually done by albuminuria/24h and the use of creatinine clearance. The objective of this study was to evaluate the renal function in Type 2 diabetes by using different formulas of creatinine clearance and to assess the contribution of cystatin C; 83 adults with type 2 diabetes (23 men and 60 women) and 83 adult controls (40 men and 43 women) were studied. Biochemical parameters were determinated on Coba 6000™ (Roche diagnostics). Diabetics showed a significant increase in blood glucose, cholesterol, triglycerides, LDLc, the ApoB, Lp(a), urea, uric acid, creatinine and cystatin C and lower HDLc. Cystatin was increased in patients with degenerative complications and in hypertensive patients. We found strong correlations of cystatin C with creatinine (r = 0.9454), urea (r = 0.8999) and uric acid (r = 0.8325). We found a significant exponentially increase of creatinine and cystatin C from one stage to another. Cystatin C has a strong association with MDRD (r = 0.8086) and CG (r = 0.7915) and a low one with creatinine clearance (r = 0.1044). In conclusion, the use of cystatin C for screening and early treatment of incipient diabetic nephropathy appears to be adequate. CG and MDRD formulas still hold their place, in regards to the classical determination of creatinine clearance, to monitor patients. PMID:22565176

  5. A case of delayed methotrexate clearance following administration of a complementary medication containing chlorophyll.

    Science.gov (United States)

    Brooks, Sally L; Sanders, Julie; Seymour, John F; Mellor, James D

    2014-06-01

    A 54-year-old male with relapsed primary cerebral lymphoma and normal renal function was treated with methotrexate (MTX) 3 g/m(2) monthly by intravenous infusion. Throughout treatment the patient self-administered a complementary medicine (Jason Winter's chlorophyll®), which he was advised to cease during methotrexate treatment due to the potential for unknown interactions. For the first four cycles, chlorophyll was ceased two days prior to commencement of methotrexate and withheld until clearance. These cycles were administered without complication, and the methotrexate level reduced to chlorophyll was not ceased and there were no changes to concomitant medications. A literature search found no documented interactions between methotrexate and chlorophyll and the chemotherapy was administered without a delay in treatment. The methotrexate level three days post-administration was 0.36 µmol/L and did not reduce to chlorophyll 48 h prior to methotrexate administration until clearance. There were no further episodes of delayed methotrexate clearance. No impurities were detected in a sample of Jason Winter's chlorophyll®. It is therefore likely that the patient's delayed methotrexate clearance was due to an interaction with chlorophyll. It is recommended that such chlorophyll containing preparations be avoided in patients treated with methotrexate.

  6. 77 FR 37706 - Agency Information Collection Activities: 30-Day Notice of Intention To Request Clearance of...

    Science.gov (United States)

    2012-06-22

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE INTERIOR National Park Service Agency Information Collection Activities: 30-Day Notice of Intention To Request Clearance of Collection of Information; Opportunity for Public Comment AGENCY: National Park Service,...

  7. 76 FR 56214 - 60-Day Notice of Intention To Request Clearance for Information Collection: Opportunity for...

    Science.gov (United States)

    2011-09-12

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE INTERIOR Office of the Secretary 60-Day Notice of Intention To Request Clearance for Information Collection: Opportunity for Public Comment AGENCY: Office of Youth in the Great Outdoors, Interior. ACTION: Notice...

  8. 77 FR 75110 - Agency Information Collection Activities: Proposed Collection; Comment Request-Generic Clearance...

    Science.gov (United States)

    2012-12-19

    ... other forms of information technology. Comments may be sent to Judy F. Wilson, Senior Nutrition Advisor... Food and Nutrition Service Agency Information Collection Activities: Proposed Collection; Comment Request--Generic Clearance To Conduct Formative Research AGENCY: Food and Nutrition Service (FNS),...

  9. Macroamylasemia with a markedly increased amylase clearance ratio in a patient with renal cell carcinoma.

    Science.gov (United States)

    Kazmierczak, S C; Van Lente, F; McHugh, A M; Katzin, W E

    1988-02-01

    We report hyperamylasemia, macroamylasemia, and a markedly increased amylase clearance/creatinine clearance ratio in a patient with renal cell carcinoma. Serum amylase activity was characterized as macroamylase by gel exclusion chromatography. Electrophoretic separation revealed an atypical band of amylase, migrating anodal to the S2 control fraction. Electrophoresis of urine revealed the presence of both S1 and S2 fractions, but not the atypical band found in serum. Quantification of the salivary- and pancreatic-type amylase fractions showed amylase in urine to be 100% salivary. Immunofixation disclosed the macroamylase to consist of an immune complex between amylase and IgA-lambda antibody. Binding-capacity studies showed that the serum immunoglobulin was present in excess and could bind 46% and 49% additional S-type amylase activity derived from saliva and the patient's urine, respectively. The amylase clearance/creatinine clearance ratio was markedly supranormal (0.134), unexpected in a patient with macroamylasemia. A biopsy specimen of the renal cell tumor was found to contain significant salivary-type amylase activity. These results suggest production of amylase by tumor tissue in the renal carcinoma and secretion of S-type amylase into the patient's urine. Evidently, macroamylase should be confirmed by gel exclusion chromatography.

  10. Specificity of increased amylase to creatinine clearance ratio in acute pancreatitis.

    Science.gov (United States)

    Lankisch, P G; Koop, H; Otto, J; Oberdieck, U; Winckler, K; Wolfrum, D I

    1977-01-01

    The amylase to creatinine clearance ratio was found to be normal in 11 of 33 patients with acute pancreatitis. The ratio was elevated in 10 of 19 patients with renal insufficiency. Thus, it does not seem to be a specific index in the diagnosis of acute pancreatitis.

  11. HLA Preferences for Conserved Epitopes: A Potential Mechanism for Hepatitis C Clearance

    NARCIS (Netherlands)

    Rao, X.; Hoof, I.; Baarle, D. van; Kesmir, C.; Textor, J.C.

    2015-01-01

    Hepatitis C virus (HCV) infections affect more than 170 million people worldwide. Most of these individuals are chronically infected, but some clear the infection rapidly. Host factors seem to play a key role in HCV clearance, among them are the human leukocyte antigen (HLA) class I molecules. Certa

  12. Determining deposition sites of inhaled lung particles and their effect on clearance

    International Nuclear Information System (INIS)

    An essential component of lung defense is clearance of particulates and infectious vectors from the mucus membrane of the tracheobronchial tree and the alveolar regions of the lung. To partition clearance between these areas we determined the bronchial branching pattern, the anatomical sites of particle deposition, and subsequent clearance in the same animal. Using a 2.85-microns particle tagged with 57Co for inhalation and deposition in the sheep lung, we followed clearance via a series of computer-stored gamma-scintillation lung images. The same sheep was reinhaled, and the particle distributions for both inhalations were compared. After the animals were killed, the bronchial branching pattern and length of the bronchial tree were documented. The number of particles depositing in all bronchi down to 1 mm diam was determined by scintillation counting, and the number in respiratory bronchioles and alveoli was microscopically counted. We conclude that particles deposited in bronchi greater than or equal to 1 mm diam clear in 2-4 h postdeposition. Bronchi distal to 1-mm-diam bronchi and alveoli clear evenly over 72 h, and the number of particles equal to the tracheobronchial deposition cleared after 45 h

  13. Clearance of senescent cells by ABT263 rejuvenates aged hematopoietic stem cells in mice

    NARCIS (Netherlands)

    Chang, Jianhui; Wang, Yingying; Shao, Lijian; Laberge, Remi-Martin; Demaria, Marco; Campisi, Judith; Janakiraman, Krishnamurthy; Sharpless, Norman E; Ding, Sheng; Feng, Wei; Luo, Yi; Wang, Xiaoyan; Aykin-Burns, Nukhet; Krager, Kimberly; Ponnappan, Usha; Hauer-Jensen, Martin; Meng, Aimin; Zhou, Daohong

    2015-01-01

    Senescent cells (SCs) accumulate with age and after genotoxic stress, such as total-body irradiation (TBI). Clearance of SCs in a progeroid mouse model using a transgenic approach delays several age-associated disorders, suggesting that SCs play a causative role in certain age-related pathologies. T

  14. Patients with ovarian cancer have elevated (51)Cr-EDTA plasma clearance early post-operatively

    DEFF Research Database (Denmark)

    Nielsen, S S; Havsteen, H; Petersen, L K;

    2002-01-01

    Plasma clearance of (51)Cr-EDTA (Clp(EDTA)) is widely used to determine glomerular filtration rate prior to carboplatin based chemotherapy. We have observed that many patients with ovarian cancer have elevated Clp in the early post-operative phase compared to later phases. The purpose of this stu...

  15. Glucose clearance in aged trained skeletal muscle during maximal insulin with superimposed exercise

    DEFF Research Database (Denmark)

    Dela, Flemming; Mikines, K J; Larsen, J J;

    1999-01-01

    Insulin and muscle contractions are major stimuli for glucose uptake in skeletal muscle and have in young healthy people been shown to be additive. We studied the effect of superimposed exercise during a maximal insulin stimulus on glucose uptake and clearance in trained (T) (1-legged bicycle tra...

  16. Effect of glycation of albumin on its renal clearance in normal and diabetic rats

    International Nuclear Information System (INIS)

    Two independent techniques have been used to study the renal clearances of nonenzymatically glycated albumin and nonglycated albumin in normal and streptozotocin-induced diabetic rats, 16 to 24 weeks after the onset of diabetes. In the first technique, serum and urinary endogenous glycated and nonglycated albumin were separated using m-aminophenylboronate affinity chromatography and subsequently quantified by radioimmunoassay. Endogenous glycated albumin was cleared approximately twofold faster than nonglycated albumin in normal and diabetic rats. However, no difference was observed in the glycated albumin/nonglycated albumin clearance ratios (Cga/Calb) in normal and diabetic rats, respectively (2.18 +/- 0.39 vs 1.83 +/- 0.22, P greater than 0.05). The second technique measured the renal clearance of injected 125I-labelled glycated albumin and 125I-labelled albumin. The endogenous results were supported by the finding that 125I-labelled glycated albumin was cleared more rapidly than 125I-labelled albumin in normal (P less than 0.01) and diabetic (P less than 0.05) rats. The Cga/Calb ratio calculated for the radiolabelled albumins was 1.4 and 2.0 in normal and diabetic rats, respectively. This evidence suggests that nonenzymatic glycation of albumin increases its renal clearance to a similar degree in normal and diabetic rats

  17. Reduced erythrocyte susceptibility and increased host clearance of young parasites slows Plasmodium growth in a murine model of severe malaria

    Science.gov (United States)

    Khoury, David S.; Cromer, Deborah; Best, Shannon E.; James, Kylie R.; Sebina, Ismail; Haque, Ashraful; Davenport, Miles P.

    2015-05-01

    The best correlate of malaria severity in human Plasmodium falciparum (Pf) infection is the total parasite load. Pf-infected humans could control parasite loads by two mechanisms, either decreasing parasite multiplication, or increasing parasite clearance. However, few studies have directly measured these two mechanisms in vivo. Here, we have directly quantified host clearance of parasites during Plasmodium infection in mice. We transferred labelled red blood cells (RBCs) from Plasmodium infected donors into uninfected and infected recipients, and tracked the fate of donor parasites by frequent blood sampling. We then applied age-based mathematical models to characterise parasite clearance in the recipient mice. Our analyses revealed an increased clearance of parasites in infected animals, particularly parasites of a younger developmental stage. However, the major decrease in parasite multiplication in infected mice was not mediated by increased clearance alone, but was accompanied by a significant reduction in the susceptibility of RBCs to parasitisation.

  18. A multi-compartment model for slow bronchial clearance of insoluble particles - Extension of the ICRP human respiratory tract models

    International Nuclear Information System (INIS)

    To incorporate the various mechanisms that are presently assumed to be responsible for the experimentally observed slow bronchial clearance into the HRTM, a multi-compartment model was developed to simulate the clearance of insoluble particles in the tracheobronchial tree of the human lung. The new model considers specific mass transfer paths that may play an important role for slow bronchial clearance. These include the accumulation of particulate mass in the peri-ciliary sol layer, phagocytosis of stored particles by airway macrophages and uptake of deposited mass by epithelial cells. Besides the gel layer representing fast mucociliary clearance, all cellular and non-cellular units involved in the slow clearance process are described by respective compartments that are connected by specific transfer rates. The gastrointestinal tract and lymph nodes are included into the model as final accumulation compartments, to which mass is transferred via the airway route and the transepithelial path. Predicted retention curves correspond well with previously published data. (authors)

  19. Correlates of spontaneous clearance of hepatitis C virus in a Danish human immunodeficiency virus type 1 cohort

    DEFF Research Database (Denmark)

    Clausen, Louise Nygaard; Weis, Nina; Schønning, Kristian;

    2011-01-01

    Abstract Background: Around a quarter of individuals infected with hepatitis C virus (HCV) are spontaneously able to clear the virus. Correlates of spontaneous HCV clearance are not well established and the aim of this study was to characterize factors associated with spontaneous HCV clearance...... in a human immunodeficiency virus (HIV)-co-infected cohort. Methods: We analyzed 327 anti-HCV-positive HIV-1-infected patients using multivariate logistic regression. HCV clearance was defined as the presence of anti-HCV with undetectable HCV RNA from at least 2 measurements more than 6 months apart. Results......) 18-28) had cleared their HCV infection and 251 (77%; 95% CI 72-82) had a chronic infection. The clearance rate in HBsAg-positive individuals was 65%. Being female, HBsAg-positive, or belonging to HIV exposure groups IDU and MSM predicted higher HCV clearance rates (adjusted odds ratio (aOR) 1.8, 95...

  20. 5-DOF Dynamic Model of Vehicle Shimmy System with Clearance at Universal Joint in Steering Handling Mechanism

    Directory of Open Access Journals (Sweden)

    Jianwei Lu

    2013-01-01

    Full Text Available 5-DOF dynamic model of vehicle shimmy system with clearance in universal joint of steering handling mechanism is presented. The sub model of cross shaft universal joint with clearance is built based on Hertz' theory, and two-state model is applied to describe the contact force. The sub model of the universal joint is combined with the simplified dynamic model of steering system, and a 5-DOF dynamic model of vehicle shimmy system with consideration of assembling clearance in universal joint of steering handling mechanism is presented. Based on this model, numerical analysis is carried out to evaluate the influence of clearance in universal joint on the dynamic behavior of the vehicle shimmy system. The results show that the clearance and some other parameters, such as vehicle speed, have coupled contribution to the dynamic behavior of the vehicle shimmy system. The conclusions provide theoretical basis for effective attenuation of vehicle shimmy, especially for those in-service vehicles.

  1. The value of level III clearance in patients with axillary and sentinel node positive breast cancer.

    LENUS (Irish Health Repository)

    Dillon, Mary F

    2012-02-01

    BACKGROUND: The value of level III axillary clearance is contentious, with great variance worldwide in the extent and levels of clearance performed. OBJECTIVE: To determine rates of level III positivity in patients undergoing level I-III axillary clearance, and identify which patients are at highest risk of involved level III nodes. METHODS: From a database of 2850 patients derived from symptomatic and population-based screening service, 1179 patients who underwent level I-III clearance between the years 1999-2007 were identified. The pathology, surgical details, and prior sentinel nodes biopsies of patients were recorded. RESULTS: Eleven hundred seventy nine patients had level I-III axillary clearance. Of the patients, 63% (n = 747) were node positive. Of patients with node positive disease, 23% (n = 168) were level II positive and 19% (n = 141) were level III positive. Two hundred fifty patients had positive sentinel node biopsies prior to axillary clearance. Of these, 12% (n = 30) and 9% (n = 22) were level II and level III positive, respectively. On multivariate analysis, factors predictive of level III involvement in patients with node positive disease were tumor size (P < 0.001, OR = 1.36; 95% CI: 1.2-1.5), invasive lobular disease (P < 0.001, OR = 3.6; 95% CI: 1.9-6.95), extranodal extension (P < 0.001, OR = 0.27; 95% CI: 0.18-0.4), and lymphovascular invasion (P = 0.04, OR = 0.58; 95% CI: 0.35-1). Lobular invasive disease (P = 0.049, OR = 4.1; 95% CI: 1-16.8), extranodal spread (P = 0.003, OR = 0.18; 95% CI: 0.06-0.57), and having more than one positive sentinel node (P = 0.009, OR = 4.9; 95% CI: 1.5-16.1) were predictive of level III involvement in patients with sentinel node positive disease. CONCLUSION: Level III clearance has a selective but definite role to play in patients who have node positive breast carcinoma. Pathological characteristics of the primary tumor are of particular use in identifying those who are at various risk of level III nodal

  2. Tip-Clearance Vortex Characterized With Three-Dimensional Digital Particle Image Velocimetry

    Science.gov (United States)

    John, W. Trevor

    2002-01-01

    An optical measurement technique known as Three-Dimensional Digital Particle Image Velocimetry (3-D DPIV) was used to characterize the tip clearance flow in NASA Glenn Research Center's low-speed axial compressor. 3-D DPIV is a technique in which a stereoscopic imaging system consisting of two cross-correlation cameras is used to record particles entrained in a flow as a laser light sheet is pulsed at two instances in time. Although 3-D DPIV has been used elsewhere, this is the first time it has been used to measure compressor tip clearance flows. In-house modifications of the DPIV system include the use of effective seeding technology and a novel system to perform a priori calibrations at all five measurement planes, greatly reducing facility run time. Computational fluid dynamics predictions, which are used to guide design changes toward improving the efficiency and operating range of turbomachinery, can be verified and improved by comparison with 3-D DPIV measurements of the actual tip clearance flow. This measurement campaign dealt with the characterization of the tip clearance vortex in the first stage of a four-stage axial compressor. The tip clearance vortex is formed in compressors operating with a clearance gap between the moving rotor blade tips and the stationary casing when a leakage flow, forced from the pressure side of the blade over the blade tip, forms a vortical structure on the suction side of the blade. 3-D DPIV is ideally suited to measure the clearance vortex for two reasons: (1) this technique captures the entire blade passage flow at one instant in time, so that wandering of the vortex during the measurement does not smear out velocity gradients in the flow field, and (2) the spanwise component of velocity changes sign across the vortex core, providing a more accurate measurement of the vortex location than was available with previous two-dimensional measurement approaches. These two attributes of the data will enable computational fluid

  3. Effect of increased surface tension and assisted ventilation on /sup 99m/Tc-DTPA clearance

    International Nuclear Information System (INIS)

    Experiments were performed to determine the effects of conventional mechanical ventilation (CMV) and high-frequency oscillation (HFO) on the clearance of technetium-99m-labeled diethylenetriamine pentaacetate (/sup 99m/Tc-DTPA) from lungs with altered surface tension properties. A submicronic aerosol of /sup 99m/Tc-DTPA was insufflated into the lungs of anesthetized, tracheotomized rabbits before and 1 h after the administration of the aerosolized detergent dioctyl sodium sulfosuccinate (OT). Rabbits were ventilated by one of four methods: 1) spontaneous breathing; 2) CMV at 12 cmH2O mean airway pressure (MAP); 3) HFO at 12 cmH2O MAP; 4) HFO at 16 cmH2O MAP. Administration of OT resulted in decreased arterial PO2 (PaO2), increased lung wet-to-dry weight ratios, and abnormal lung pressure-volume relationships, compatible with increased surface tension. /sup 99m/Tc-DTPA clearance was accelerated after OT in all groups. The post-OT rate of clearance (k) was significantly faster (P less than 0.05) in the CMV at 12 cmH2O MAP [k = 7.57 +/- 0.71%/min (SE)] and HFO at 16 cmH2O MAP (k = 6.92 +/- 0.61%/min) groups than in the spontaneously breathing (k = 4.32 +/- 0.55%/min) and HFO at 12 cmH2O MAP (4.68 +/- 0.63%/min) groups. The clearance curves were biexponential in the former two groups. We conclude that pulmonary clearance of /sup 99m/Tc-DTPA is accelerated in high surface tension pulmonary edema, and this effect is enhanced by both conventional ventilation and HFO at high mean airway pressure

  4. Clearance of extractables and leachables from single-use technologies via ultrafiltration/diafiltration operations.

    Science.gov (United States)

    Magarian, Nicholas; Lee, Kate; Nagpal, Kunal; Skidmore, Ken; Mahajan, Ekta

    2016-05-01

    Quantifying the clearance of extractables and leachables (E/L) throughout ultrafiltration/diafiltration (UFDF) operations allows for greater flexibility in the implementation of single-use technologies in steps upstream of the UFDF process. A proof-of-concept study was completed in which the clearance of 7 E/L from single-use technologies (trimethylsilanol, hexanoic acid, butyrolactone, t-butyl alcohol, caprolactam, acetonitrile, and benzyl alcohol) in four representative proteins were measured and monitored during the UFDF process using quantitative NMR. This study demonstrated that the defined E/L spiked into a variety of protein solutions can be cleared to 1 ppm, which is explained in detail. The overall clearance trend observed for both buffer control and protein-containing solutions resembled the ideal clearance trend where no apparent interactions were observed between E/L with the protein, UFDF system, or with other defined E/L which may be present in the system. Additionally, the UFDF system is capable of clearing these potential E/L from single-use technologies below 1 ppm irrespective of initial concentrations in the load (1,000 or 100 ppm), independently from the type of protein. In general, mass recoveries were within ±15% of each spiked compound in protein solutions and their respective buffer controls, suggesting spiked E/L do not interact strongly with protein. By demonstrating the product independent clearance trends of the spiked E/L across UFDF, these results will contribute to the simplification of the E/L toxicology assessment and allow modular manufacturing approach for single-use technologies in biopharmaceutical manufacturing. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:718-724, 2016. PMID:27071939

  5. Interspecies allometric scaling. Part I: prediction of clearance in large animals.

    Science.gov (United States)

    Mahmood, I; Martinez, M; Hunter, R P

    2006-10-01

    Interspecies scaling is a useful tool for the prediction of pharmacokinetic parameters from animals to humans, and it is often used for estimating a first-time in human dose. The knowledge of pharmacokinetics in veterinary species is important for dosage selection, particularly in the treatment of large zoo animal species, such as elephants, giant cats and camels, for which pharmacokinetic data are scant. Therefore, the accuracy in clearance predictions in large animal species, with and without the use of correction factors (rule of exponents), and the impact of species selection in the prediction of clearance in large animal species was examined. Based upon this analysis, it was determined that there is a much larger risk of inaccuracies in the clearance estimates in large animal species when compared with that observed for humans. Unlike in humans, for large animal species, correction factors could not be applied because there was no trend between the exponents of simple allometry and the appropriate correction factor for improving our predictions. Nevertheless, we did see an indication that the exponents of simple allometry may alert us as to when the predicted clearance in the large animal may be underestimated or overpredicted. For example, if a large animal is included in the scaling, the predicted clearance in a large animal should be considered overestimated if the exponent of simple allometry is >1.3. Despite the potential for extrapolation error, the reality is that allometric scaling is needed across many veterinary practice situations, and therefore will be used. For this reason, it is important to consider mechanisms for reducing the risk of extrapolation errors that can seriously affect target animal safety, therapeutic response, or the accuracy of withdrawal time predictions. PMID:16958787

  6. The metabolic clearance rate of corticosterone in lean and obese male Zucker rats

    International Nuclear Information System (INIS)

    The obese Zucker rat is an animal model of human juvenile-onset obesity. These rats exhibit numerous endocrine and metabolic abnormalities. Adrenalectomy of obese rats has been shown to reduce or reverse several of these abnormalities, thereby implying that corticosterone may contribute to the expression of obesity in this animal. Furthermore, it has been shown that the circadian rhythm of plasma corticosterone is disturbed in obese Zucker rats resulting in elevated morning plasma corticosterone concentrations in obese rats as compared to lean rats. In a effort to better elucidate the mechanism of the elevated morning levels of plasma corticosterone, the metabolic clearance rate of corticosterone was determined in the morning for lean and obese male Zucker rats (12 to 20 weeks). Additionally, the biliary and urinary excretion of labeled corticosterone and/or its metabolites were determined. The metabolic clearance rate of corticosterone was significantly greater in obese rats than in their lean counterparts. Both the metabolic clearance rate and the volume of compartments significantly correlated with body weight. No correlation was found between body weight and the elimination rate constant. The increased metabolic clearance rate of obese rats appeared to be due to an increase in the physiologic distribution of corticosterone and not to an alteration in the enzymes responsible for corticosterone metabolism. It appears that the metabolic clearance rate of corticosterone in obese Zucker rats does not contribute to elevated morning concentrations of plasma corticosterone previously observed in these animals. It suggests that the adrenal corticosterone secretion rate must actually be greater than one would expect from the plasma corticosterone concentrations alone

  7. 99mTc-HEPIDA hepatic clearance as a diagnostic tool: usefulness of plasma and hepatic clearance for assessment of hepatic parenchyma performance.

    Science.gov (United States)

    Frieske, Izabela; Surma, Marian J; Bieńkiewicz, Małgorzata; Białkowska-Warzecha, Jolanta; Liniecki, Julian; Kuydowicz, Jan; Kuśmierek, Jacek

    2003-01-01

    Plasma clearance of (99m)Tc-HEPIDA (Cl(Pl)) has been used for two decades for assessment of liver function in patients with diseases of this organ. A specific determination of (99m)Tc-HEPIDA liver clearance (Cl(Hp)) has been developed that provides more direct possibility to evaluate performance of liver parenchyma. Both tests have been studied in healthy volunteers of varying age (48 individuals) and in 83 patients with varying degree of liver damage. The liver damage has been evaluated on the basis of 5 biochemical tests (AspAT, ALAT, GGTP, bilirubine serum concentration, proteinogram) and a score system used for total impairment, which was calculated for each patient. Normal range of Cl(Pl) and Cl(Hp) was determined from a study on healthy individuals (volunteers). The results seem independent of age, but show sex differences. The following values (mean +/- SD) of Cl(Hp) were found in males and females of: (181 +/- 31) ml//min/1.73 m(2) and (158 +/- 22) ml/min/1.73m(2), and of Cl(Pl) were (224 +/- 33) ml/min/1.73 m(2) and (202 +/- 25) ml/min/1.73 m(2) respectively. Accepted lower boundaries of both quantities (mean -2SD) are 115 ml/min/1.73 m(2) and 150 ml/min/1.73 m(2) correspondingly. Negative correlation of individual values of both clearances in all patients with individual score of liver damage were highly significant and correlation coefficients obtained were higher for Cl(Hp) (r = -0.63) than those for Cl(Pl) (r= -0.56). Factorial analysis was performed with the intention of seeing which of the studied factors had the highest factor loading for parenchyma performance that was assumed as the common factor responsible for correlations. The highest value was obtained for hepatic clearance (Cl(Hp)) of (99m)Tc-HEPIDA. In conclusion this quantity seems highly promising as a clinically useful test for assessment of liver performance, both in screening for liver damage and for monitoring of organ conditions during therapy and follow-up of patients.

  8. The clearance concept with special reference to determination of glomerular filtration rate in patients with fluid retention.

    Science.gov (United States)

    Henriksen, Ulrik L; Henriksen, Jens H

    2015-01-01

    In subjects without fluid retention, the total plasma clearance of a renal filtration indicator (inulin, (99m) Tc-DTPA, (51) Cr-EDTA) is close to the urinary plasma clearance. Conversely, in patients with fluid retention (oedema, pleural effusions, ascites), there is a substantial discrepancy between the total plasma clearance and the urinary plasma clearance. This is owing to delayed indicator distribution to smaller or larger parts of the interstitial space, which in patients with ascites may simulate a peritoneal dialysator. In patients with fluid retention, urinary plasma clearance should be assessed to obtain a correct measurement of the glomerular filtration rate (GFR). In theory, total plasma clearance with late samples (24-h, 48-h) may be applied in patients with fluid retention, but validation hereof has not been performed. Until such studies are completed, it is recommended that patients with fluid retention have their GFR measured by a urinary plasma clearance technique with controlled quantitative urinary sampling within a few hours after indicator injection.

  9. Effects of a Nonuniform Tip Clearance Profile on the Performance and Flow Field in a Centrifugal Compressor

    Directory of Open Access Journals (Sweden)

    Yohan Jung

    2012-01-01

    Full Text Available This paper presents a numerical investigation of the effects of a nonuniform tip clearance profile on the performance and flow field in a centrifugal compressor with a vaneless diffuser. This study focuses in particular on the magnitude and location of the wake. Six impellers with different tip clearance profiles were tested in the flow simulations. The accuracy of the numerical simulations was assessed by comparing the experimental data with the computational results for a system characterized by the original tip clearance. Although the performance improved for low tip clearances, a low tip clearance at the trailing edge improved the compressor performance more significantly than a low tip clearance at the leading edge. The flow field calculated for a system characterized by a low tip clearance at the trailing edge produced a more uniform velocity distribution both in the circumferential and in the axial directions at the impeller exit because the wake magnitude was reduced. As a consequence, this impeller provided a better potential for diffusion processes inside a vaneless diffuser.

  10. Dual-Track Clearance of Circulating Bacteria Balances Rapid Restoration of Blood Sterility with Induction of Adaptive Immunity.

    Science.gov (United States)

    Broadley, Steven P; Plaumann, Ann; Coletti, Raffaele; Lehmann, Christin; Wanisch, Andreas; Seidlmeier, Amelie; Esser, Knud; Luo, Shanshan; Rämer, Patrick C; Massberg, Steffen; Busch, Dirk H; van Lookeren Campagne, Menno; Verschoor, Admar

    2016-07-13

    Efficient clearance of bacteremia prevents life-threatening disease. Platelet binding to intravascular bacteria, a process involving platelet glycoprotein GPIb and bacterial opsonization with activated complement C3, influences blood clearance and anti-infective immunity. Using intravital microscopy of the bloodstream of mice infected with Listeria monocytogenes, we show that bacterial clearance is not a uniform process but a "dual-track" mechanism consisting of parallel "fast" and "slow" pathways. "Slow clearance" is regulated by time-dependent bacterial opsonization, stochastic platelet binding, and capture of bacteria-platelet-complexes via the complement receptor of the immunoglobulin superfamily, CRIg. The mechanism spares some bacteria from "fast clearance" and rapid destruction in the liver via Kupffer cell scavenger receptors, keeping them available for adaptive immunity induction by splenic CD8α(+) dendritic cells. We consistently find "fast" and "slow" clearance patterns for a broad panel of other Gram+ and Gram- bacteria. Thus, dual-track clearance balances rapid restoration of blood sterility with induction of specific antibacterial immunity. PMID:27345696

  11. Esophageal Acid Clearance During Random Swallowing Is Faster in Patients with Barrett’s Esophagus Than in Healthy Controls

    Science.gov (United States)

    Lottrup, Christian; Krarup, Anne L; Gregersen, Hans; Ejstrud, Per; Drewes, Asbjørn M

    2016-01-01

    Background/Aims Impaired esophageal acid clearance may be a contributing factor in the pathogenesis of Barrett’s esophagus. However, few studies have measured acid clearance as such in these patients. In this explorative, cross-sectional study, we aimed to compare esophageal acid clearance and swallowing rate in patients with Barrett’s esophagus to that in healthy controls. Methods A total of 26 patients with histology-confirmed Barrett’s esophagus and 12 healthy controls underwent (1) upper endoscopy, (2) an acid clearance test using a pH-impedance probe under controlled conditions including controlled and random swallowing, and (3) an ambulatory pH-impedance measurement. Results Compared with controls and when swallowing randomly, patients cleared acid 46% faster (P = 0.008). Furthermore, patients swallowed 60% more frequently (mean swallows/minute: 1.90 ± 0.74 vs 1.19 ± 0.58; P = 0.005), and acid clearance time decreased with greater random swallowing rate (P 0.3). Conclusions More frequent swallowing and thus faster acid clearance in Barrett’s esophagus may constitute a protective reflex due to impaired mucosal integrity and possibly acid hypersensitivity. Despite these reinforced mechanisms, acid clearance ability seems to be overthrown by repeated, retrograde acid reflux, thus resulting in increased esophageal acid exposure and consequently mucosal changes. PMID:27557545

  12. Hepatic clearance of {sup 99m}Tc-GSA in cases of postoperative biliary atresia. A retrospective comparison with hepatic clearance of {sup 99m}Tc-PMT

    Energy Technology Data Exchange (ETDEWEB)

    Yamazaki, Tetsuro; Yamada, Shogo [Tohoku Univ., Sendai (Japan). School of Medicine; Maruoka, Shin

    1998-11-01

    There are a few reports about usefulness of {sup 99m}Tc-GSA liver scintigraphy (GSA imaging) for the evaluation of postoperative state of biliary atresia. However, comparison of significance for the disease between GSA imaging and {sup 99m}Tc-PMT hepatobiliary imaging have not been reported. Fifty-six GSA imagings for 41 postoperative biliary atresia patients were reviewed and their scintigraphic findings and the functional parameters were compared with those obtained from {sup 99m}Tc-PMT hepatobiliary imaging. In quantitative analysis, although the hepatic clearance of both tracers calculated by graphical analysis (Patlak plot) were well correlated in most cases, a discrepancy was observed in several cases with jaundice. The authors conclude that the hepatic clearance of {sup 99m}Tc-GSA is a more accurate index of the hepatic reserve than that of {sup 99m}Tc-PMT which can be influenced by hyperbilirubinemia and that the combination of both examinations is helpful to evaluate development of liver injury in postoperative biliary atresia patients. (author)

  13. [Hepatic clearance of 99mTc-GSA in cases of postoperative biliary atresia--a retrospective comparison with hepatic clearance of 99mTc-PMT].

    Science.gov (United States)

    Yamazaki, T; Maruoka, S; Yamada, S

    1998-11-01

    There are a few reports about usefulness of 99mTc-GSA liver scintigraphy (GSA imaging) for the evaluation of postoperative state of biliary atresia. However, comparison of significance for the disease between GSA imaging and 99mTc-PMT hepatobiliary imaging have not been reported. Fifty-six GSA imagings for 41 postoperative biliary atresia patients were reviewed and their scintigraphic findings and the functional parameters were compared with those obtained from 99mTc-PMT hepatobiliary imaging. In quantitative analysis, although the hepatic clearance of both tracers calculated by graphical analysis (Patlak plot) were well correlated in most cases, a discrepancy was observed in several cases with jaundice. The authors conclude that the hepatic clearance of 99mTc-GSA is a more accurate index of the hepatic reserve than that of 99mTc-PMT which can be influenced by hyperbilirubinemia and that the combination of both examinations is helpful to evaluate development of liver injury in postoperative biliary atresia patients. PMID:9916401

  14. Interscapular brown adipose tissue blood flow in the rat. Determination with 133xenon clearance compared to the microsphere method

    DEFF Research Database (Denmark)

    Astrup, A; Bülow, J; Madsen, J

    1984-01-01

    a close correlation to the blood flow values determined with microspheres. Y = 0.98. X + 0.15 (r = 0.96, P less than 0.001). The Xe clearance method has the advantages compared to the microsphere technique that it permits continuous monitoring of the blood flow and does not require the sacrifice......The xenon clearance method was adapted to continuous measurement of interscapular brown adipose tissue (ISBAT) blood flow in anesthetized rats. The ISBAT-blood partition coefficient for xenon was determined to 3.6 ml X g-1. The blood flow values obtained by Xe clearance were compared with flow...

  15. Robust Foot Clearance Estimation Based on the Integration of Foot-Mounted IMU Acceleration Data

    Directory of Open Access Journals (Sweden)

    Mourad Benoussaad

    2015-12-01

    Full Text Available This paper introduces a method for the robust estimation of foot clearance during walking, using a single inertial measurement unit (IMU placed on the subject’s foot. The proposed solution is based on double integration and drift cancellation of foot acceleration signals. The method is insensitive to misalignment of IMU axes with respect to foot axes. Details are provided regarding calibration and signal processing procedures. Experimental validation was performed on 10 healthy subjects under three walking conditions: normal, fast and with obstacles. Foot clearance estimation results were compared to measurements from an optical motion capture system. The mean error between them is significantly less than 15 % under the various walking conditions.

  16. Stochastic model of ultrafine particle deposition and clearance in the human respiratory tract

    International Nuclear Information System (INIS)

    Deposition and clearance of insoluble ultrafine particles, ranging from 1 to 100 nm, were simulated by stochastic models using Monte Carlo methods. Brownian motion is the dominant mode of deposition in human airways. The additional effects of convective diffusion in bifurcations and axial diffusion (convective mixing) primarily affect particle transport and deposition of particles in the 1-10 nm range. Regarding total deposition, the effects of both convective mechanisms are practically compensated by the concomitant effect of molecular radial diffusion (Brownian motion). During the first hours following inhalation, 1 nm particles are predicted to be cleared much faster than particles in the size range from 10 to 100 nm, with a retained fraction of about 80% after 24 h. For 1-10 nm particles, extracellular transfer to blood is the most likely mode of clearance, while uptake and subsequent accumulation in epithelial cells are assumed to be the preferential mechanisms for 10-100 nm particles. (author)

  17. Effects of the impeller inlet tip clearance on the flow and performance of airfoil fans

    Energy Technology Data Exchange (ETDEWEB)

    Kang, S.H. [Seoul National University, Seoul (Korea); Kim, Y.J. [Seoul National University Graduate School, Seoul (Korea)

    1999-08-01

    Performance tests of an airfoil fan and measurement of flow fields at the impeller exit are carried out to investigate the effects of the tip clearance between the rotor and inlet casing on the impeller performance. The impeller is twelve bladed of NACA 65-810 airfoils and tested with 3 different size of gap; 1, 2, 4{sup mm}. The relative decrease of pressure rising performance of the fan is 15 percent for the design flow rate when the gap size is 1 percent of the impeller diameter. The reduction of performance becomes large as the flow rate increases. The leakage flow through the clearance affects the through flow of the impeller, which results in decrease of the slip factor as well as the impeller efficiency. The data base obtained in the present study can be used for the design and flow analysis of the airfoil fans. (author). 4 refs., 19 figs., 1 tab.

  18. Effects of Long-duration Space Flight on Toe Clearance During Treadmill Walking

    Science.gov (United States)

    Miller, Chris; Peters, Brian; Brady, Rachel; Mulavara, Ajitkumar; Richards, Jason; Hayat, Matthew; Bloomberg, Jacob

    2008-01-01

    Upon returning from long-duration space flight, astronauts and cosmonauts must overcome physiologic and sensorimotor changes induced by prolonged exposure to microgravity as they readapt to a gravitational environment. Their compromised balance and coordination lead to an altered and more variable walking pattern (Bloomberg & Mulavara, 2003; McDonald, et al., 1996). Toe trajectory during the swing phase of locomotion has been identified as a precise motor control task (Karst, et al., 1999), thus providing an indication of the coordination of the lower limbs (Winter, 1992). Failure to achieve sufficient toe clearance may put the crew member at a greater risk of tripping and falling, especially if an emergency egress from the vehicle should be necessary upon landing. The purpose of this study was to determine the pre- to post-flight changes in toe clearance in crew members returning from long-duration missions and the recovery thereafter.

  19. The role of tip clearance in high-speed fan stall

    Science.gov (United States)

    Adamczyk, J. J.; Celestina, M. L.; Greitzer, E. M.

    1991-01-01

    A numerical experiment has been carried out to define the near-stall casing endwall flowfield of a high-speed fan rotor. The experiment used a simulation code incorporating a simple clearance model, whose calibration is presented. The results of the simulation show that the interaction of the tip leakage vortex and the in-pasage shock plays a major role in determining the fan flow range. More specifically, the computations imply that it is the area increase of this vortex as it passes through the in-passage shock, which is the source of the blockage associated with stall. In addition, for fans of this type, it is the clearance over the forward portion of the fan blade which controls the flow processes leading to stall.

  20. Long-term clearance of accidentally inhaled 60Co aerosols in humans

    International Nuclear Information System (INIS)

    Long-term body retention was measured on six workers inhaling 60Co aerosols incidentally during manipulation with a high activity 60Co source. An improved whole body counter technique and calibration provided good conditions to follow the body clearance over 4 years. A two-detector profile scanning arrangement was used to measure the activity distribution 'in vivo' over the lung region. The observed whole body retention followed a two-exponential time function between 10-1500 days. The consistency of the measured retention pattern with ICRP inhalation model was investigated assuming different aerosol size distributions. A possible extension of ICRP lung model is proposed to take into account the actual pulmonary lung clearance determined individually. (R.P.) 29 refs.; 15 figs.; 6 tabs

  1. CD47 in Erythrocyte Ageing and Clearance - the Dutch Point of View.

    Science.gov (United States)

    Burger, Patrick; de Korte, Dirk; van den Berg, Timo K; van Bruggen, Robin

    2012-10-01

    Recently, an important role for CD47, a well-known 'don't eat me' signal, in the clearance of aged erythrocytes was revealed. Experimental data support the conversion of CD47 from a 'don't eat me' to an 'eat me' signal through a conformational change in CD47. Intriguingly, erythrocyte phagocytosis after this switch seems to be mediated by the same receptor that normally signals inhibition of phagocytosis, SIRPα. In this review, the possible molecular mechanisms leading to this conformational change in CD47 as well as the possible signal transduction events leading to phagocytosis after this switch are discussed. Lastly, the consequences of this newly identified mode of erythrocyte phagocytosis for the clearance of aged erythrocytes during normal turnover and after erythrocyte transfusion are addressed. PMID:23801927

  2. Combination of Aβ clearance and neurotrophic factors as a potential treatment for Alzheimer's disease

    Institute of Scientific and Technical Information of China (English)

    Lian-Feng Lin; Min-Jing Liao; Xiao-Yan Xue; Wei Zhang; Li Yan; Liang Cai; Xiao-Wen Zhou

    2013-01-01

    There is no effective drug to treat Alzheimer's disease (AD),a neurodegenerative disease affecting an estimated 30 million people around the world.Strongly supported by preclinical and clinical studies,amyloid-beta (Aβ) may be a target for developing drugs against AD.Meanwhile,the fact that localized neuronal death/loss and synaptic impairment occur in AD should also be considered.Neuronal regeneration,which does not occur normally in the mammalian central nervous system,can be promoted by neurotrophic factors (NTFs).Evidence from clinical trials has shown that both Aβ clearance and NTFs are potentially effective in treating AD,thus a new approach combining Aβ clearance and administration of NTFs may be an effective therapeutic strategy.

  3. Estimation of hurdle clearance parameters using a monocular human motion tracking method.

    Science.gov (United States)

    Krzeszowski, Tomasz; Przednowek, Krzysztof; Wiktorowicz, Krzysztof; Iskra, Janusz

    2016-09-01

    This paper presents a method of monocular human motion tracking for estimation of hurdle clearance kinematic parameters. The analysis involved 10 image sequences of five hurdlers at various training levels. Recording of the sequences was carried out under simulated starting conditions of a 110 m hurdle race. The parameters were estimated using the particle swarm optimization algorithm and they are based on analysis of the images recorded with a 100 Hz camera. The proposed method does not involve using any special clothes, markers, inertial sensors, etc. As the quality criteria, the mean absolute error and mean relative error were used. The level of computed errors justifies the use of this method to estimate hurdle clearance parameters. PMID:26838547

  4. Serum amylase determinations and amylase to creatinine clearance ratios in patients with chronic renal insufficiency.

    Science.gov (United States)

    Tedesco, F J; Harter, H R; Alpers, D H

    1976-10-01

    Patients with severe chronic renal failure may have significant hyperamylasemia in the absence of clinical symptoms or signs of acute pancreatitis. Amylase to creatinine clearance (CA/CC) ratios were usually elevated in patients with chronic renal failure and were not helpful in evaluating the possibility of acute pancreatitis. The mean amylase to creatinine clearance ratio for the controls with normal renal function was 1.24 +/- 0.13. In patients with chronic renal failure, it was 3.17 +/- 0.42 (P less than 0.001). Serum amylase isoenzyme patterns revealed no difference in salivary to pancreatic isoenzyme ratios between normals (1.04 +/- 0.12) and patients with severe renal insufficiency without evidence of pancreatic disease (1.07 +/- 0.13). The isoenzymes were helpful in excluding the diagnosis of pancreatic in 1 renal failure patient whose hyperamylasemia was primarily salivary in origin and in confirming the diagnosis in another who had only a pancreatic band.

  5. Trypsin/creatinine clearance ratio and serum immunoreactive trypsin in digestive and pancreatic diseases.

    Science.gov (United States)

    Del Favero, G; Fabris, C; Bonvicini, P; Piccoli, A; Baccaglini, U; Pedrazzoli, S; Burlina, A; Naccarato, R

    1985-01-01

    The behavior of trypsin/creatinine clearance ratio (Ctr/Ccr) and serum immunoreactive trypsin (IRT) was evaluated in a total of 168 subjects with pancreatic cancer, chronic pancreatitis and non-pancreatic digestive diseases. Amylase/creatinine clearance ratio (Cam/Ccr) and serum amylase levels were also evaluated in order to establish their possible relationship with Ctr/Ccr and IRT values. Elevated Ctr/Ccr and IRT values were observed in several patients with pancreatic cancer and chronic pancreatitis. Abnormal IRT and Ctr/Ccr values were found in 28.2 and 4% of non-pancreatic digestive diseases, respectively. IRT and amylase serum levels showed consensual modifications, while Ctr/Ccr showed a behavior different from that of Cam/Ccr. Liver damage seems to play a role in increasing serum IRT levels of patients without pancreatic involvement, while the increased Ctr/Ccr seems to depend on other factors, for instance renal tubular dysfunction.

  6. Dynamic load sharing behavior of transverse-torsional coupled planetary gear train with multiple clearances

    Institute of Scientific and Technical Information of China (English)

    盛冬平; 朱如鹏; 靳广虎; 陆凤霞; 鲍和云

    2015-01-01

    A new nonlinear transverse-torsional coupled model with backlash and bearing clearance was proposed for planetary gear set. Meanwhile, sun gear and planet’s eccentricity errors, static transmission error, and time-varying meshing stiffness were taken into consideration. The differential governing equations of motion were solved by employing variable step-size Rung-Kutta numerical integration method. The behavior of dynamic load sharing characteristics affected by the system parameters including input rate, sun gear’s supporting stiffness and eccentricity error, planet’s eccentricity error, sun gear’s bearing clearance, backlashes of sun-planet and planet-ring meshes were investigated qualitatively and systematically. Some theoretical results are summarized at last which extend the current understanding of the dynamic load sharing behavior of planet gear train, enrich the related literature and provide references for the design of planetary gear train.

  7. Performance verification test on wet-blast type decontamination for the clearance

    International Nuclear Information System (INIS)

    The decontamination test was carried out to verify its performance of the wet blast decontamination device which is placed in Fugen Decommissioning Engineering Center, Japan Atomic Energy Agency and to determine the optimal conditions for decontamination using test specimens gathered from pipes of facilities which are going to be applied for the clearance. According to the test result, the contamination on inner surface of the pipes can be removed easily by more than 100 of decontamination factor with rust and its coating and can be decontaminated in less than clearance level in relatively short period of blasting process. Besides, it was proved that the optimal condition for decontamination is 0.4 MPa in blast pressure and 100 mm in blast distance, which is the basic specification of the device. (author)

  8. Diagnostics of automatic compensators of valve clearance in combustion engine with the use of vibration signal

    Science.gov (United States)

    Szymański, Grzegorz M.; Tomaszewski, Franciszek

    2016-02-01

    Dynamic development of internal combustion engines creates a need to adopt a strategy concerning operational use of these driving units based on the knowledge of their technical condition. The assessment of technical condition belongs to tasks of technical diagnostics. This article presents an analysis of issues concerning vibration diagnostics of automatic compensators of clearances in piston valves of combustion engine. Scientific experiments focused on delivering information necessary to create (and also to validate) diagnostic models enabling assessment of technical condition of those elements of combustion engine that are essential taking into account effectiveness and durability that were carried out and described here. On the basis of the worked out diagnostic model, the algorithm for assessment of the technical condition of automatic compensators of valve clearance was created.

  9. Lung inflammation does not affect the clearance kinetics of lipid nanocapsules following pulmonary administration.

    Science.gov (United States)

    Patel, Aateka; Woods, A; Riffo-Vasquez, Yanira; Babin-Morgan, Anna; Jones, Marie-Christine; Jones, Stuart; Sunassee, Kavitha; Clark, Stephen; T M de Rosales, Rafael; Page, Clive; Spina, Domenico; Forbes, Ben; Dailey, Lea Ann

    2016-08-10

    Lipid nanocapsules (LNCs) are semi-rigid spherical capsules with a triglyceride core that present a promising formulation option for the pulmonary delivery of drugs with poor aqueous solubility. Whilst the biodistribution of LNCs of different size has been studied following intravenous administration, the fate of LNCs following pulmonary delivery has not been reported. We investigated quantitatively whether lung inflammation affects the clearance of 50nm lipid nanocapsules, or is exacerbated by their pulmonary administration. Studies were conducted in mice with lipopolysaccharide-induced lung inflammation compared to healthy controls. Particle deposition and nanocapsule clearance kinetics were measured by single photon emission computed tomography/computed tomography (SPECT/CT) imaging over 48 h. A significantly lower lung dose of (111)In-LNC50 was achieved in the lipopolysaccharide (LPS)-treated animals compared with healthy controls (p<0.001). When normalised to the delivered lung dose, the clearance kinetics of (111)In-LNC50 from the lungs fit a first order model with an elimination half-life of 10.5±0.9h (R(2)=0.995) and 10.6±0.3h (R(2)=1.000) for healthy and inflamed lungs respectively (n=3). In contrast, (111)In-diethylene triamine pentaacetic acid (DTPA), a small hydrophilic molecule, was cleared rapidly from the lungs with the majority of the dose absorbed within 20min of administration. Biodistribution to lungs, stomach-intestine, liver, trachea-throat and blood at the end of the imaging period was unaltered by lung inflammation. This study demonstrated that lung clearance and whole body distribution of lipid nanocapsules were unaffected by the presence of acute lung inflammation. PMID:27180635

  10. Exclusion, exemption and clearance in the mining and minerals industry: Practical application to South African operations

    International Nuclear Information System (INIS)

    Although South Africa has no primary uranium mines, a major portion of its very large mining industry involves minerals with moderately elevated levels of naturally-occurring radionuclides, typical of elevated levels found in similar mineral deposits worldwide. Evidence both locally and internationally suggests that, where radioactive elements are not concentrated or extracted, such operations cannot normally give rise to undue radiological risks. The concept of exclusion should therefore play the major role in establishing which minerals-related operations should be subject to regulatory control, but exclusion criteria, which tend to be numerical rather than descriptive, vary widely between countries - in South Africa, very little is excluded and opportunities for granting exemptions are limited. The need for exemptions and clearance would be reduced if more extensive use of the exclusion concept were made, but it is nevertheless important to have better guidance on determining appropriate numerical exemption and clearance criteria - again, there are currently wide variations between countries, one example being the surface activity clearance levels for the reuse or recycling of uranium-contaminated items. Two examples, relating to gold mining tailings disposal and recycling of contaminated scrap steel respectively, are used to illustrate the difficulties that have arisen in South Africa on the clearance of low activity materials from the mining and minerals industry. Radon is identified as requiring separate consideration, and is the one area where more specific international guidance, based on action levels for intervention, is available. The action level for workplaces recommended by the IAEA would appear to represent a common basis for exclusion and exemption with respect to radon exposures from mining and minerals operations. For public exposures, the corresponding action level for homes, although not specifically intended for dealing with radon from nearby

  11. Accelerated clearance of human red blood cells in a rat transfusion model

    OpenAIRE

    Straat, M.; Klei, TRL; de Korte, D; van Bruggen, R.; Juffermans, NP

    2015-01-01

    Background Animal models are valuable in transfusion research. Use of human red blood cells (RBCs) in animal models facilitates extrapolation of the impact of storage conditions to the human condition but may be hampered by the use of cross species. Methods Investigation of clearance and posttransfusion recovery in a rat model using fresh and stored human RBCs. Results Directly following transfusion, human RBCs could be detected in the circulation of all recipients, with higher recovery rates...

  12. Insulin Clearance and the Incidence of Type 2 Diabetes in Hispanics and African Americans

    OpenAIRE

    Lee, C. Christine; Haffner, Steven M.; Wagenknecht, Lynne E.; Lorenzo, Carlos; Norris, Jill M.; Bergman, Richard N.; Stefanovski, Darko; Anderson, Andrea M.; Jerome I Rotter; Goodarzi, Mark O; Hanley, Anthony J.

    2013-01-01

    OBJECTIVE We aimed to identify factors that are independently associated with the metabolic clearance rate of insulin (MCRI) and to examine the association of MCRI with incident type 2 diabetes in nondiabetic Hispanics and African Americans. RESEARCH DESIGN AND METHODS We investigated 1,116 participants in the Insulin Resistance Atherosclerosis Study (IRAS) Family Study with baseline examinations from 2000 to 2002 and follow-up examinations from 2005 to 2006. Insulin sensitivity (SI), acute i...

  13. Insulin Sensitivity and Insulin Clearance are Heritable and Have Strong Genetic Correlation in Mexican Americans

    OpenAIRE

    Goodarzi, Mark O; Langefeld, Carl D.; Xiang, Anny H.; Chen, Yii-Der I.; Guo, Xiuqing; Hanley, Anthony J. G.; Raffel, Leslie J.; Kandeel, Fouad; Thomas A Buchanan; Norris, Jill M.; Fingerlin, Tasha E.; Lorenzo, Carlos; Rewers, Marian J; Haffner, Steven M.; Donald W Bowden

    2014-01-01

    Objective We describe the GUARDIAN (Genetics UndeRlying DIAbetes in HispaNics) consortium, along with heritability estimates and genetic and environmental correlations of insulin sensitivity and metabolic clearance rate of insulin (MCRI). Design and Methods GUARDIAN is comprised of seven cohorts, consisting of 4336 Mexican-American individuals in 1346 pedigrees. Insulin sensitivity (SI), MCRI, and acute insulin response (AIRg) were measured by frequently sampled intravenous glucose tolerance ...

  14. Design analysis and development of a high temperature actuaror for gas turbine blade tip clearance control

    OpenAIRE

    Coşkun, Mustafa Bulut; Coskun, Mustafa Bulut

    2011-01-01

    During a typical startup cycle industrial gas turbine blades experience rapid radial thermal expansion while bulky shroud structure with larger thermal inertia requires much longer period to reach its operating temperature. Turbine designers have to leave a safe radial distance in order to prevent contact of blades to the surrounding annular casing. However, when thermal steady state in the turbine stage is achieved, shroud and casing grow and excessive amount of blade-shroud clearance remain...

  15. Mathematical modeling and analysis of insulin clearance in vivo

    OpenAIRE

    Gilles Ernst; Koschorreck Markus

    2008-01-01

    Abstract Background Analyzing the dynamics of insulin concentration in the blood is necessary for a comprehensive understanding of the effects of insulin in vivo. Insulin removal from the blood has been addressed in many studies. The results are highly variable with respect to insulin clearance and the relative contributions of hepatic and renal insulin degradation. Results We present a dynamic mathematical model of insulin concentration in the blood and of insulin receptor activation in hepa...

  16. Modeling and simulation of wear in revolute clearance joints in multibody systems

    OpenAIRE

    Flores, Paulo

    2009-01-01

    The main goal of this work is to develop a methodology for studying and quantifying the wear phenomenon in revolute clearance joints. In the process, a simple model for a revolute joint in the framework of multibody systems formulation is presented. The evaluation of the contact forces developed is based on a continuous contact force model that accounts for the geometrical and materials properties of the colliding bodies. The friction effects due to the contact in the joints are also represen...

  17. Effects of PM2 5 exposure on Klebsiella pneumoniae clearance in the lungs of rats

    Institute of Scientific and Technical Information of China (English)

    段争

    2014-01-01

    Objective To investigate the effects of PM2.5 exposure on susceptibility to Klebsiella infection and bacterial clearance,and to discuss its possible mechanisms.Methods Eighty-six healthy male SD rats were randomly divided into 4 groups:a control group,a Klebsiella pneumoniae infection group(infection group),a PM2.5 group and a PM2.5

  18. Measurements of the Flow in Backshroud/Casing Clearance of Precessing Centrifugal Impeller

    OpenAIRE

    Yoshiki Yoshida; Yoshinobu Tsujimoto; Hideo Ohashi; Akira Saito; Shin Ishizaki

    1997-01-01

    Detailed flow measurements have been made to clarify the unsteady flow in the backshroud/ casing clearance of a precessing centrifugal impeller. The unsteady pressure was integrated to obtain the fluid force moment on the precessing impeller shroud for various precessing frequencies. It was shown that the fluid force moment can become rotordynamically destabilizing for small forward precessing motion as originally found by Ohashi et al. The effects of leakage flow in the backshroud/casing cle...

  19. Numerical error evaluation for tip clearance flow calculations in a centrifugal compressor

    OpenAIRE

    Dufour, Guillaume; CARBONNEAU, Xavier; Arbez, Pierre; Cazalbou, Jean-Bernard; Chassaing, Patrick

    2004-01-01

    Since globally mesh independent solution are still beyond available computer resources for industrial cases, a method to quantify locally the numerical error is proposed. The design of experiments method helps selecting mesh parameters that influence the tip clearance solution, so that additional meshes are computed to evaluate the numerical error on the shroud friction coefficient. In the field of CFD applied to turbomachinery, this study results from a partnership between ENSICA, Liebher...

  20. Modeling and Vibration Suppression for Telescopic Systems of Structural Members with Clearance

    OpenAIRE

    Arnold, Dieter; Mittwollen, Martin; Schönung, Frank; Wauer, Jörg; Barthels, Pierre

    2006-01-01

    Telescopic systems of structural members with clearance are found in many applications, e.g., mobile cranes, rack feeders, fork lifters, stacker cranes (see Figure 1). Operating these machines, undesirable vibrations may reduce the performance and increase safety problems. Therefore, this contribution has the aim to reduce these harmful vibrations. For a better understanding, the dynamic behaviour of these constructions is analysed. The main interest is the overlapping area of each two sectio...

  1. Manual hyperinflation in airway clearance in pediatric patients: a systematic review

    OpenAIRE

    de Godoy, Vanessa Cristina Waetge Pires; Zanetti, Nathalia Mendonça; Johnston, Cíntia

    2013-01-01

    Objective To perform an assessment of the available literature on manual hyperinflation as a respiratory physical therapy technique used in pediatric patients, with the main outcome of achieving airway clearance. Methods We reviewed articles included in the Lilacs (Latin American and Caribbean Literature on Health Sciences/Literatura Latino Americana e do Caribe em Ciências da Saúde), Cochrane Library, Medline (via Virtual Health Library and PubMed), SciELO (Scientific Electronic Library), an...

  2. [Plasma clearance of ethanol and its excretion in the milk of rural women who consume pulque].

    Science.gov (United States)

    Argote-Espinosa, R M; Flores-Huerta, S; Hernández-Montes, H; Villalpando-Hernández, S

    1992-01-01

    Women from rural areas of the central plateau of Mexico drink during pregnancy and lactation a mild alcoholic beverage called pulque as a galactogogue. Ethanol present in milk could have a harmful effect on growth and development of breast-fed children. The purpose of this study was to quantify the ethanol consumed as pulque by eleven lactating rural women as well as its clearance rate in blood and milk. Mothers were separated in two groups depending upon the ethanol ingested in a single dose of pulque 0.21 +/- 0.08 g/kg of body weight (group A) and 0.44 +/- 0.11 g/kg (group B). Maximal concentration of ethanol was reached in milk at 60 minutes and almost equaled that in plasma. Both groups showed a similar clearance pattern regardless of the volume of pulque ingested. Clearance rates between groups were different: ethanol concentration in milk at 60 min were 8.4 +/- 3.0 mg/dL for group A and 26.2 +/- 7.0 mg/dL for group B. Two hours later ethanol levels were 3.6 +/- 3.4 mg/dL and 23.3 +/- 9.4 mg/dL respectively. Clearance rates were slower in mothers showing the highest concentration of ethanol in milk. The present data demonstrate that there is no differential elimination of ethanol in maternal blood and milk following ingestion of a moderate amount of pulque during lactation. The amount of ethanol received by infants through milk is relatively low and therefore it is unlikely to have harmful effects on them. Pulque consumption adds about 350 kcal/day to the customary dietary intake of these lactating women.

  3. Lung cinescintigraphy in the dynamic assessment of ventilation and mucociliary clearance of asbestos cement workers.

    OpenAIRE

    Di Lorenzo, L; Mele, M; Pegorari, M M; Fratello, A; Zocchetti, C; Capozzi, D.

    1996-01-01

    OBJECTIVES: To verify in vivo whether lung cinescintigraphy confirms the effect of asbestos on the patency of the smallest airways and on the efficiency of mucociliary clearance in asbestos cement workers. METHODS: 39 male subjects were examined: 30 asbestos cement workers and nine workers never exposed to occupational respiratory irritants. All subjects had a chest radiograph (International Labour Organisation (ILO) 1980); standard questionnaire on chronic bronchitis; spirometry; arterial bl...

  4. IL-10 Neutralization Promotes Parasite Clearance in Splenic Aspirate Cells From Patients With Visceral Leishmaniasis

    OpenAIRE

    Gautam, Shalini; Kumar, Rajiv; Maurya, Radheshyam; Nylén, Susanne; Ansari, Nasim; Rai, Madhukar; Sundar, Shyam; Sacks, David

    2011-01-01

    The mechanisms underlying the failure to contain the growth of Leishmania parasites in human visceral leishmaniasis (VL) are not understood. L donovani amastigotes were quantified in cultured splenic aspirate cells to assess the function of IL-10 in lesional tissue ex vivo. In 67 patients with active VL, IL-10 neutralization promoted parasite killing in 73% and complete clearance in 30%, while 18% had more parasites and 9% did not change. The splenic cells secreted increased levels of both tu...

  5. Direct measurement of first-pass ileal clearance of a bile acid in humans

    International Nuclear Information System (INIS)

    The purpose of this study was to develop and validate a method of directly measuring ileal bile acid absorption efficiency during a single enterohepatic cycle (first-pass ileal clearance). This has become feasible for the first time because of the availability of the synthetic gamma-labeled bile acid 75Selena-homocholic acid-taurine (75SeHCAT). Together with the corresponding natural bile acid cholic acid-taurine (labeled with 14C), SeHCAT was infused distal to an occluding balloon situated beyond the ampulla of Vater in six healthy subjects. Completion of a single enterohepatic cycle was assessed by obtaining a plateau for 75SeHCAT activity proximal to the occluding balloon, which prevented further cycles. Unabsorbed 75SeHCAT was collected after total gut washout, which was administered distal to the occluding balloon. 75SeHCAT activity in the rectal effluent measured by gamma counter was compared with that of absorbed 75SeHCAT level measured by gamma camera and was used to calculate first-pass ileal clearance. This was very efficient (mean value, 96%) and showed very little variation in the six subjects studied (range, 95%-97%). A parallel time-activity course in hepatic bile for 14C and 75Se during a single enterohepatic cycle, together with a ratio of unity for 14C/75Se in samples obtained at different time intervals, suggests that 75SeHCAT is handled by the ileum like the natural bile acid cholic acid-taurine. Extrapolation of 75SeHCAT first-pass ileal clearance to that of the natural bile acid therefore seems justifiable. In a subsidiary experiment, ileal absorption efficiency per day for 75SeHCAT was also measured by scanning the gallbladder area on 5 successive days after the measurement of first-pass ileal clearance. In contrast with absorption efficiency per cycle, absorption efficiency per day varied widely (49%-86%)

  6. THE EFFECT OF NORMAL SALINE AND 3.5% HYPERTONIC SALINE ON MUCOCILIARY CLEARANCE IN SINUSITIS

    Directory of Open Access Journals (Sweden)

    Mahesh

    2014-10-01

    Full Text Available Introduction: Sinusitis is usually treated with antibiotics, decongestants, mucolytics and steroids. Long term use of these drugs has many side effects. This has led to the use of other modalities of treatment such as saline nasal irrigation. Saline nasal irrigation helps in clearance of secretions, debris and crusts, thus improving the mucociliary clearance. OBJECTIVE: This randomized comparative study was undertaken to assess the ciliary function by performing saccharine test and to evaluate the effect of 3.5% hypertonic saline nasal drops against normal saline nasal drops on mucociliary transit time of saccharine. MATERIALS AND METHODS: Fifty patients diagnosed as chronic sinusitis in the age group of 18 to 45 years were randomized into two groups; Group A treated with 0.9% normal saline and Group B with 3.5% hypertonic saline for a period of 4 weeks. Mucociliary transit time was recorded by performing saccharine test before and after treatment. RESULTS: Significant improvement was seen in both the groups but when compared to normal saline, hypertonic saline significantly improved the mucociliary clearance. The mean mucociliary transit time of saccharine in Group A patients before treatment was 19.860 minutes and after treatment was 17.634 minutes (t=14.012, p=0.0001. The mean mucociliary transit time of saccharine in Group B patients before treatment was 21.881 minutes and after treatment was 16.689 minutes (t=14.662, p=0.0001. All the patients reported relief of symptoms, but relief was much earlier in Group B when compared to Group A. Mild burning sensation in the nose and throat was reported by 4% of patients in Group A and 8% in Group B. CONCLUSION: Both 0.9% normal saline and 3.5% hypertonic saline significantly improved the mucociliary clearance. Hypertonic saline is more efficacious than normal saline in the treatment of chronic sinusitis

  7. The influence of propranolol on the cardiovascular effects and plasma clearance of epinephrine.

    OpenAIRE

    Ichinohe, T; IGARASHI, O.; Kaneko, Y.

    1991-01-01

    The purpose of the present study was to determine how propranolol modifies the circulatory effects of epinephrine infused to produce plasma concentrations achieved during dental local anesthesia and to evaluate the effects of propranolol on the plasma clearance of epinephrine. The study was performed on six healthy male volunteers ranging in age from 25 to 34 yr. Five measurement series were performed on each of these subjects at the following times: pretreatment control, 15 min after the beg...

  8. Role of plaque in the clearance of salivary sucrose and its influence on salivary ph

    OpenAIRE

    Kumar, A; R Hedge; U Dixit

    2011-01-01

    Background: The prevalence of dental caries in children, in India, is higher than many of the industrialized countries. The sugar most commonly associated with dental caries is sucrose, as the microorganisms in the dental plaque have the ability to convert this dietary constituent into various organic acids. Aims and Objectives: This study was conducted to study the effect of the presence of plaque on the salivary clearance of sucrose and to study the effect of the presence of plaque on saliv...

  9. Serum and Glucocorticoid-Regulated Kinase 1 Regulates Neutrophil Clearance during Inflammation Resolution

    OpenAIRE

    Burgon, Joseph; Robertson, Anne L.; Sadiku, Pranvera; Wang, Xingang; Hooper-Greenhill, Edward; Prince, Lynne R.; Walker, Paul; Hoggett, Emily E.; Ward, Jonathan R.; Farrow, Stuart N.; William J Zuercher; Jeffrey, Philip; Savage, Caroline O.; Ingham, Philip W.; Hurlstone, Adam F.

    2014-01-01

    The inflammatory response is integral to maintaining health by functioning to resist microbial infection and repair tissue damage. Large numbers of neutrophils are recruited to inflammatory sites to neutralize invading bacteria through phagocytosis and the release of proteases and reactive oxygen species into the extracellular environment. Removal of the original inflammatory stimulus must be accompanied by resolution of the inflammatory response, including neutrophil clearance, to prevent in...

  10. Serum and Glucocorticoid Regulated Kinase 1 (SGK1) Regulates Neutrophil Clearance During Inflammation Resolution

    OpenAIRE

    Burgon, Joseph; Robertson, Anne L.; Sadiku, Pranvera; Wang, Xingang; Hooper-Greenhill, Edward; Prince, Lynne R.; Walker, Paul; Hoggett, Emily E.; Ward, Jonathan R.; Farrow, Stuart N.; William J Zuercher; Jeffrey, Philip; Savage, Caroline O.; Ingham, Philip W.; Hurlstone, Adam F.

    2014-01-01

    The inflammatory response is integral to maintaining health, by functioning to resist microbial infection and repair tissue damage. Large numbers of neutrophils are recruited to inflammatory sites to neutralise invading bacteria through phagocytosis and the release of proteases and reactive oxygen species into the extracellular environment. Removal of the original inflammatory stimulus must be accompanied by resolution of the inflammatory response, including neutrophil clearance, to prevent i...

  11. Lower Pole Calyceal Stone and Lithotripsy are Issues with Clearance Fact or Reality?

    Directory of Open Access Journals (Sweden)

    M. Hammad Ather

    2013-12-01

    Full Text Available The lower pole calyceal (LPC stone continues to be an enigma. The complex anatomy of the lower pole collecting system, along with other factors like acute pelvi calyceal angle and narrow and long infundibulum, are some of the complicating factors affecting stone clearance. There have been many studies assessing the impact of collecting system anatomy and most conclude that the complex anatomy of the lower pole collecting system does impact the overall stone-free rate.

  12. Effects on water quality from mud clearance operations in the Pezze' hydropower basin (Trentino, Italy)

    International Nuclear Information System (INIS)

    The present paper describes dynamic concentration for various parameters, that have been monitored through both continuous and instant samplings, during maintenance operations (mud deposit clearance) in a hydropower basin along Torrent Avisio in Trentino region, Italy. Aim of the work is to demonstrate that, during such operations, an organic water pollution occur besides turbidity. The former is well expressed by a marked value increment of different parameters, as total phosphorus, ammonium and organic matter

  13. Effect of inspiratory resistance and PEEP on /sup 99m/Tc-DTPA clearance

    International Nuclear Information System (INIS)

    Experiments were performed to determine the effect of markedly negative pleural pressure (Ppl) or positive end-expiratory pressure (PEEP) on the pulmonary clearance (k) of technetium-99m-labeled diethylenetriaminepentaacetic acid (/sup 99m/Tc-DTPA). A submicronic aerosol containing /sup 99m/Tc-DTPA was insufflated into the lungs of anesthetized intubated sheep. In six experiments k was 0.44 +/- 0.46% (SD)/min during the initial 30 min and was unchanged during the subsequent 30-min interval [k = 0.21 +/- 12%/min] when there was markedly increased inspiratory resistance. A 3-mm-diam orifice in the inspiratory tubing created the resistance. It resulted on average in a 13-cmH2O decrease in inspiratory Ppl. In eight additional experiments sheep were exposed to 2, 10, and 15 cmH2O PEEP (20 min at each level). During 2 cmH2O PEEP k = 0.47 +/- 0.15%/min, and clearance increased slightly at 10 cmH2O PEEP [0.76 +/- 0.28%/min, P less than 0.01]. When PEEP was increased to 15 cmH2O a marked increase in clearance occurred [k = 1.95 +/- 1.08%/min, P less than 0.001]. The experiments demonstrate that markedly negative inspiratory pressures do not accelerate the clearance of /sup 99m/Tc-DTPA from normal lungs. The effect of PEEP on k is nonlinear, with large effects being seen only with very large increases in PEEP

  14. Solute clearance effect of citrate anticoagulation hemodialysate for hemodialysis in patients with high risk of bleeding

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Objective To study the solute clearance effect of the new concentrated anticoagulation hemodialysate of citrate for hemodialysis in patients with high risk of bleeding. Methods Forty-two kidney failure patients with high risk of bleeding were divided into two groups (Group A and Group B) according to their hemodialysis manners. Patients in Group A were hemodialyzed with bicarbonate hemodialysate with low-molecular-weight heparin (dalteparin) anticoagulation and those in Group B with the new citrate anticoag...

  15. Determination of the rates of clearance of insoluble compounds of plutonium from the lung

    International Nuclear Information System (INIS)

    There are indications that the process of clearance of inhaled insoluble plutonium compounds from the lung may be represented by a model consisting of three exponential phases. A survey of published data on 'in vivo' and bioassay measurements made after 239PuO2 inhalation by men and dogs has been carried out, and the half times of the three exponential phases determined as approximately 1 day, 30 days and 500 days. (author)

  16. Storage of Gold Nanoclusters in Muscle Leads to their Biphasic in Vivo Clearance

    OpenAIRE

    Zhang, Xiao-Dong; Luo, Zhentao; Chen, Jie; Wang, Hao; Song, Sha Sha; Shen, Xiu; Long, Wei; Sun, Yuan-Ming; Fan, Saijun; Zheng, Kaiyuan; Leong, David Tai; Xie, Jianping

    2014-01-01

    Ultrasmall gold nanoclusters show great potential in biomedical applications. Long term biodistribution, retention, toxicity, and pharmacokinetics profiles are prerequisites in their potential clinical applications. Here we systematically investigated the biodistribution, clearance, and toxicity of one widely used Au NC species glutathione protected Au NCs or GSH Au NCs, over a relatively long period of 90 days in mice. We observed that most of the Au NCs were cleared at 30 days post injectio...

  17. Structural Health Monitoring on Turbine Engines Using Microwave Blade Tip Clearance Sensors

    Science.gov (United States)

    Woike, Mark; Abdul-Aziz, Ali; Clem, Michelle

    2014-01-01

    The ability to monitor the structural health of the rotating components, especially in the hot sections of turbine engines, is of major interest to aero community in improving engine safety and reliability. The use of instrumentation for these applications remains very challenging. It requires sensors and techniques that are highly accurate, are able to operate in a high temperature environment, and can detect minute changes and hidden flaws before catastrophic events occur. The National Aeronautics and Space Administration (NASA) has taken a lead role in the investigation of new sensor technologies and techniques for the in situ structural health monitoring of gas turbine engines. As part of this effort, microwave sensor technology has been investigated as a means of making high temperature non-contact blade tip clearance, blade tip timing, and blade vibration measurements for use in gas turbine engines. This paper presents a summary of key results and findings obtained from the evaluation of two different types of microwave sensors that have been investigated for use possible in structural health monitoring applications. The first is a microwave blade tip clearance sensor that has been evaluated on a large scale Axial Vane Fan, a subscale Turbofan, and more recently on sub-scale turbine engine like disks. The second is a novel microwave based blade vibration sensor that was also used in parallel with the microwave blade tip clearance sensors on the experiments with the sub-scale turbine engine disks.

  18. Sidestream smoke inhalation decreases respiratory clearance of 99mTc-DTPA acutely

    International Nuclear Information System (INIS)

    The permeability of the alveolar-capillary barrier to an inhaled aerosol of technetium 99m labelled diethylenetriamine penta-acetate (99mTc-DTPA is used as an index of alveolar epithelial injury. Permeability is greatly increased in active smokers. The aim of this study was to determine the effect of sidestream smoke inhalation on permeability as this has not been described previously. Lung clearance of inhaled 99mTc-DTPA aerosol was measured in 20 normal non-smoking subjects before and after exposure to one hours sidestream smoke inhalation. Measured carbon monoxide (CO) levels rose to a maximum of 23.5 ±6.2 ppm from baseline values of 0.6±1.3 (p99mTc-DTPA clearance rose from baseline 69.1± 15.6 (mean ± to 77.4 ±17.8) after smoke exposure. No effect of 99mTc-DTPA scanning of sidestream smoke was demonstrated on lung function. It was concluded that low level sidestream smoke inhalation decreases 99mTc-DTPA clearance acutely in humans. The mechanism of this unexpected result is not established but may include differences in constituents between sidestream and mainstream smoke, alterations in pulmonary microvascular blood flow, or changes in surfactant due to an acute phase irritant response. 34 refs., 2 figs

  19. A novel approach to achieving modular retrovirus clearance for a parvovirus filter.

    Science.gov (United States)

    Stuckey, Juliana; Strauss, Daniel; Venkiteshwaran, Adith; Gao, Jinxin; Luo, Wen; Quertinmont, Michelle; O'Donnell, Sean; Chen, Dayue

    2014-01-01

    Viral filtration is routinely incorporated into the downstream purification processes for the production of biologics produced in mammalian cell cultures (MCC) to remove potential viral contaminants. In recent years, the use of retentive filters designed for retaining parvovirus (~20 nm) has become an industry standard in a conscious effort to further improve product safety. Since retentive filters remove viruses primarily by the size exclusion mechanism, it is expected that filters designed for parvovirus removal can effectively clear larger viruses such as retroviruses (~100 nm). In an attempt to reduce the number of viral clearance studies, we have taken a novel approach to demonstrate the feasibility of claiming modular retrovirus clearance for Asahi Planova 20N filters. Porcine parvovirus (PPV) and xenotropic murine leukemia virus (XMuLV) were co-spiked into six different feedstreams and then subjected to laboratory scale Planova 20N filtration. Our results indicate that Planova 20N filters consistently retain retroviruses and no retrovirus has ever been detected in the filtrates even when significant PPV breakthrough is observed. Based on the data from multiple in-house viral validation studies and the results from the co-spiking experiments, we have successfully claimed a modular retrovirus clearance of greater than 6 log10 reduction factors (LRF) to support clinical trial applications in both USA and Europe.

  20. Renal Drug Dosage Adjustment According to Estimated Creatinine Clearance in Hospitalized Patients With Heart Failure.

    Science.gov (United States)

    Altunbas, Gokhan; Yazc, Mehmet; Solak, Yalcin; Gul, Enes E; Kayrak, Mehmet; Kaya, Zeynettin; Akilli, Hakan; Aribas, Alpay; Gaipov, Abduzhappar; Yazc, Raziye; Ozdemir, Kurtulus

    2016-01-01

    It is of clinical importance to determine creatinine clearance and adjust doses of prescribed drugs accordingly in patients with heart failure to prevent untoward effects. There is a scarcity of studies in the literature investigating this issue particularly in patients with heart failure, in whom many have impaired kidney function. The purpose of this study was to determine the degree of awareness of medication prescription as to creatinine clearance in patients hospitalized with heart failure. Patients hospitalized with a diagnosis of heart failure were retrospectively evaluated. Among screened charts, patients with left ventricular ejection fraction renal dose adjustment were determined and evaluated for appropriate dosing according to eGFR. A total of 388 patients with concomitant heart failure and renal dysfunction were included in the study. The total number of prescribed medications was 2808 and 48.3% (1357 medications) required renal dose adjustment. Of the 1357 medications, 12.6% (171 medications) were found to be inappropriately prescribed according to eGFR. The most common inappropriately prescribed medications were famotidine, metformin, perindopril, and ramipril. A significant portion of medications used in heart failure requires dose adjustment. Our results showed that in a typical cohort of patients with heart failure, many drugs are prescribed at inappropriately high doses according to creatinine clearance. Awareness should be increased among physicians caring for patients with heart failure to prevent adverse events related to medications.

  1. Study on the leakage flow through a clearance gap between two stationary walls

    Science.gov (United States)

    Zhao, W.; Billdal, J. T.; Nielsen, T. K.; Brekke, H.

    2012-11-01

    In the present paper, the leakage flow in the clearance gap between stationary walls was studied experimentally, theoretically and numerically by the computational fluid dynamics (CFD) in order to find the relationship between leakage flow, pressure difference and clearance gap. The experimental set-up of the clearance gap between two stationary walls is the simplification of the gap between the guide vane faces and facing plates in Francis turbines. This model was built in the Waterpower laboratory at Norwegian University of Science and Technology (NTNU). The empirical formula for calculating the leakage flow rate between the two stationary walls was derived from the empirical study. The experimental model is simulated by computational fluid dynamics employing the ANSYS CFX commercial software in order to study the flow structure. Both numerical simulation results and empirical formula results are in good agreement with the experimental results. The correction of the empirical formula is verified by experimental data and has been proven to be very useful in terms of quickly predicting the leakage flow rate in the guide vanes for hydraulic turbines.

  2. Mechanistic studies of antibody mediated clearance of tau aggregates using an ex vivo brain slice model

    Directory of Open Access Journals (Sweden)

    Pavan eKrishnamurthy

    2011-10-01

    Full Text Available Recent studies have shown that immunotherapy clears amyloid beta (A plaques and reduces A levels in mouse models of Alzheimer’s disease (AD, as well as in AD patients. Tangle pathology is also relevant for the neurodegeneration in AD, and our studies have shown that active immunization with an AD related phospho-tau peptide reduces aggregated tau within the brain and slows the progression of tauopathy-induced behavioural impairments. Thus, clearance of neurofibrillary tangles and/or their precursors may reduce synaptic and neuronal loss associated with AD and other tauopathies. So far the mechanisms involved in antibody-mediated clearance of tau pathology are yet to be elucidated. In this study we have used a mouse brain slice model to examine the uptake and localization of FITC labeled anti-tau antibodies. Confocal microscopy analysis showed that the FITC labelled anti-tau antibody co-stained with phosphorylated tau, had a perinuclear appearance and co-localised with markers of the endosomal/lysosomal pathway. Additionally, tau and FITC IgG were found together in an enriched lysosome fraction. In summary, antibody-mediated clearance of intracellular tau aggregates appears to occur via the lysosomal pathway.

  3. Loss of Acetylcholine Signaling Reduces Cell Clearance Deficiencies in Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    Sérgio M Pinto

    Full Text Available The ability to eliminate undesired cells by apoptosis is a key mechanism to maintain organismal health and homeostasis. Failure to clear apoptotic cells efficiently can cause autoimmune diseases in mammals. Genetic studies in Caenorhabditis elegans have greatly helped to decipher the regulation of apoptotic cell clearance. In this study, we show that the loss of levamisole-sensitive acetylcholine receptor, but not of a typical neuronal acetylcholine receptor causes a reduction in the number of persistent cell corpses in worms suffering from an engulfment deficiency. This reduction is not caused by impaired or delayed cell death but rather by a partial restoration of the cell clearance capacity. Mutants in acetylcholine turn-over elicit a similar phenotype, implying that acetylcholine signaling is the process responsible for these observations. Surprisingly, tissue specific RNAi suggests that UNC-38, a major component of the levamisole-sensitive receptor, functions in the dying germ cell to influence engulfment efficiency. Animals with loss of acetylcholine receptor exhibit a higher fraction of cell corpses positive for the "eat-me" signal phosphatidylserine. Our results suggest that modulation by ion channels of ion flow across plasma membrane in dying cells can influence the dynamics of phosphatidylserine exposure and thus clearance efficiency.

  4. An Optical Fiber Bundle Sensor for Tip Clearance and Tip Timing Measurements in a Turbine Rig

    Science.gov (United States)

    García, Iker; Beloki, Josu; Zubia, Joseba; Aldabaldetreku, Gotzon; Illarramendi, María Asunción; Jiménez, Felipe

    2013-01-01

    When it comes to measuring blade-tip clearance or blade-tip timing in turbines, reflective intensity-modulated optical fiber sensors overcome several traditional limitations of capacitive, inductive or discharging probe sensors. This paper presents the signals and results corresponding to the third stage of a multistage turbine rig, obtained from a transonic wind-tunnel test. The probe is based on a trifurcated bundle of optical fibers that is mounted on the turbine casing. To eliminate the influence of light source intensity variations and blade surface reflectivity, the sensing principle is based on the quotient of the voltages obtained from the two receiving bundle legs. A discrepancy lower than 3% with respect to a commercial sensor was observed in tip clearance measurements. Regarding tip timing measurements, the travel wave spectrum was obtained, which provides the average vibration amplitude for all blades at a particular nodal diameter. With this approach, both blade-tip timing and tip clearance measurements can be carried out simultaneously. The results obtained on the test turbine rig demonstrate the suitability and reliability of the type of sensor used, and suggest the possibility of performing these measurements in real turbines under real working conditions. PMID:23739163

  5. Effects of sulfuric acid aerosol on respiratory mechanics and mucociliary particle clearance in healthy nonsmoking adults

    International Nuclear Information System (INIS)

    Ten healthy nonsmokers inhaled H2SO4 at 0 (control), 110, 330, and 980 μg/m3 for one hour via nasal mask in random sequence on four separate days. Respiratory mechanical function was assessed before and after the H2SO4 exposure. A /sup 99m/Tc tagged Fe2O3 aerosol was inhaled approx. 10 min before each H2SO4 exposure. Thoracic retention of the deposited radioactivity was monitored using collimated scintillation detectors. A tracheal probe was used to determine the tracheal mucociliary trnsport rates (TMTR's) of local concentrations of activity. Bronchial mucociliary clearance was markedly altered in a dose dependent pattern in six of the individuals and in the group as a whole. The four individuals whose clearance times were not significantly affected by these H2SO4 exposures were each given an additional test with a 1000 μg/m3 H2SO4 exposure preceding the tagged Fe2O3 aerosol. Three of them responded. Thus, 9 of 10 subjects had substantial changes in bronchial clearance times following H2SO4 exposures

  6. Performance prediction and flow field calculation for airfoil fan with impeller inlet clearance

    International Nuclear Information System (INIS)

    The performance prediction of an airfoil fan using a commercial code, STAR/CD, is verified by comparing the calculated results with measured performance data and velocity fields of an airfoil fan. The effects of inlet tip clearance on performance are investigated. The calculations overestimate the pressure rise performance by about 10-25 percent. However, the performance reduction due to tip clearance is well predicted by numerical simulations. Main source of performance decrease is not only the slip factor but also impeller efficiency. The reduction in performance is 12-16 percent for 1 percent gap of the diameter. The calculated reductions in impeller efficiency and slip factor are also linearly proportional to the gap size. The span-wise distributions of phase averaged velocity and pressure at the impeller exit are strongly influenced by the radial gap size. The radial component of velocity and the flow angle increase over the passage as the gap increases. The slip factor decreases and the loss increases with the gap size. The high velocity of leakage jet affects the impeller inlet and passage flows. With a larger clearance, the main stream moves to the impeller hub side and high loss region extends from the shroud to the hub

  7. Mechanisms tagging senescent red blood cells for clearance in healthy humans

    Directory of Open Access Journals (Sweden)

    Anna eBogdanova

    2013-12-01

    Full Text Available This review focuses on the analysis and evaluation of the diverse senescence markers suggested to prime red blood cells (RBC for clearance in humans. These tags develop in the course of biochemical and structural alterations accompanying RBC aging, as the decrease of activities of multiple enzymes, the gradual accumulation of oxidative damage, the loss of membrane in form of microvesicles, the redistribution of ions and alterations in cell volume, density and deformability. The actual tags represent the penultimate galactosyl residues, revealed by desialylation of glycophorins, or the aggregates of the anion exchanger (band 3 protein to which anti-galactose antibodies bind in the first and anti-band 3 naturally occurring antibodies (NAbs in the second case. While anti-band 3 NAbs bind to the carbohydrate-free portion of band 3 aggreates in healthy humans, induced anti-lactoferrin antibodies bind to the carbohydrate-containing portion of band 3 and along with anti-band 3 NAbs may accelerated clearance of senescent RBC in patients with anti-neutrophil cytoplasmic antibodies. Exoplasmically accessible phosphatidylserine and the alterations in the interplay between CD47 on RBC and its receptor on macrophages, signal regulatory protein alpha (SIRPalpha protein, were also reported to induce erythrocyte clearance. We discuss the relevance of each mechanism and analyze the strength of the data.

  8. A Novel Approach for Reducing Rotor Tip-Clearance Induced Noise in Turbofan Engines

    Science.gov (United States)

    Khorrami, Mehdi R.; Li, Fei; Choudhari, Meelan

    2001-01-01

    Rotor tip-clearance induced noise, both in the form of rotor self noise and rotor-stator interaction noise , constitutes a significant component of total fan noise. Innovative yet cost effective techniques to suppress rotor-generated noise are, therefore, of foremost importance for improving the noise signature of turbofan engines. To that end, the feasibility of a passive porous treatment strategy to positively modify the tip-clearance flow field is addressed. The present study is focused on accurate viscous flow calculations of the baseline and the treated rotor flow fields. Detailed comparison between the computed baseline solution and experimental measurements shows excellent agreement. Tip-vortex structure, trajectory, strength, and other relevant aerodynamic quantities are extracted from the computed database. Extensive comparison between the untreated and treated tip-clearance flow fields is performed. The effectiveness of the porous treatment for altering the rotor-tip vortex flow field in general and reducing the intensity of the tip vortex, in particular, is demonstrated. In addition, the simulated flow field for the treated tip clearly shows that substantial reduction in the intensity of both the shear layer roll-up and boundary layer separation on the wall is achieved.

  9. Sensing and Identification of Nonlinear Dynamics of Slider with Clearance in Sub-5 Nanometer Regime

    Directory of Open Access Journals (Sweden)

    Gang Sheng

    2011-01-01

    Full Text Available This paper provides an overview of the problems pertaining to the sensing and identification of nonlinear dynamics of slider with clearance in sub-5 nanometer regime. This problem is complex in nature because the nonlinear dynamics of slider in sub-5 nanometer clearance regime involves different sources of nonlinear, nonstationary, and uncertainty characteristics. For example, the involved forces such as air-bearing force, intermolecular force, and contact forces are all nonlinear. The complex interface interaction with mobile lubricant makes the slider response be nonstationary. Furthermore, the interfacial parameters are available only by assumptions in the sense of statistics. Most of the reported studies either focused on physics-based simulations by using assumed interfacial parameters or focused on experimental characterization. The issues of the sensing and identification of the nonlinear dynamic properties of slider in nanometer clearance regime will be discussed with an aim at illustrating the promising approaches for improving the correlation between test data and physics-based simulations.

  10. Serum IgE clearance is facilitated by human FcεRI internalization

    Science.gov (United States)

    Greer, Alexandra M.; Wu, Nan; Putnam, Amy L.; Woodruff, Prescott G.; Wolters, Paul; Kinet, Jean-Pierre; Shin, Jeoung-Sook

    2014-01-01

    The high-affinity IgE receptor FcεRI is constitutively expressed in mast cells and basophils and is required for transmitting stimulatory signals upon engagement of IgE-bound allergens. FcεRI is also constitutively expressed in dendritic cells (DCs) and monocytes in humans; however, the specific functions of the FcεRI expressed by these cells are not completely understood. Here, we found that FcεRI expressed by human blood DC antigen 1–positive (BDCA1+) DCs and monocytes, but not basophils, traffics to endolysosomal compartments under steady-state conditions. Furthermore, IgE bound to FcεRI on BDCA1+ DCs was rapidly endocytosed, transported to the lysosomes, and degraded in vitro. IgE injected into mice expressing human FcεRIα (FCER1A-Tg mice) was endocytosed by conventional DCs and monocytes, and endocytosis was associated with rapid clearance of circulating IgE from these mice. Importantly, this rapid IgE clearance was dependent on monocytes or DCs but not basophils. These findings strongly suggest that constitutive internalization of human FcεRI by DCs and monocytes distinctively contributes to serum IgE clearance. PMID:24569373

  11. Role of plaque in the clearance of salivary sucrose and its influence on salivary ph

    Directory of Open Access Journals (Sweden)

    A Kumar

    2011-01-01

    Full Text Available Background: The prevalence of dental caries in children, in India, is higher than many of the industrialized countries. The sugar most commonly associated with dental caries is sucrose, as the microorganisms in the dental plaque have the ability to convert this dietary constituent into various organic acids. Aims and Objectives: This study was conducted to study the effect of the presence of plaque on the salivary clearance of sucrose and to study the effect of the presence of plaque on salivary pH, following sucrose clearance. Materials and Methods: Salivary sucrose determination was done by using the anthrone technique. A Digital MHOS pH meter estimated the salivary pH. Results: Presence of plaque increased the salivary sucrose clearance time and decreased the salivary pH at various time intervals. Conclusions: The microbial etiology of dental caries is the dynamic relationship among the dental plaque microbiota, dietary carbohydrates, saliva and pH lowering, and the cariogenic potential of the dental plaque. Caries occur preferentially in the dentition sites characterized by high exposure to carbohydrate and diminished salivary effect.

  12. Insulin resistance and delayed clearance of peptide hormones in cirrhotic rat liver

    International Nuclear Information System (INIS)

    Clearance of porcine insulin, glucagon, and human growth hormone was measured in intact perfused cirrhotic and normal rat livers. Binding and degradation of 125I-insulin by hepatocytes isolated from cirrhotic and normal livers were also studied. The half-lives (t/sub 1/2/) of immunoreactive insulin and glucagon were 14.0 +/- 3.1 and 9.6 +/- 2.1 min in normal livers and 26.0 +/- 6.1 and 25.0 +/- 7.1 min in cirrhotic livers. Insulin binding and degradation by hepatocytes from control and cirrhotic livers showed no significant differences. Intraportal insulin infusion in perfusion studies suppressed glucagon-stimulated increases in glucose output from control livers but failed to suppress glucose production by cirrhotic livers, suggesting the presence of hepatic insulin resistance in cirrhosis. Impaired clearance of insulin and glucagon by the intact cirrhotic liver and normal binding and degradation of insulin by isolated hepatocytes suggest that factors such as intrahepatic fibrosis and shunting and postbinding defects may be responsible for the impaired hormone clearance and hepatic insulin resistance

  13. Hyperglycemia Impairs Neutrophil-Mediated Bacterial Clearance in Mice Infected with the Lyme Disease Pathogen.

    Directory of Open Access Journals (Sweden)

    Ashkan Javid

    Full Text Available Insulin-insufficient type 1 diabetes is associated with attenuated bactericidal function of neutrophils, which are key mediators of innate immune responses to microbes as well as pathological inflammatory processes. Neutrophils are central to immune responses to the Lyme pathogen Borrelia burgdorferi. The effect of hyperglycemia on host susceptibility to and outcomes of B. burgdorferi infection has not been examined. The present study investigated the impact of sustained obesity-independent hyperglycemia in mice on bacterial clearance, inflammatory pathology and neutrophil responses to B. burgdorferi. Hyperglycemia was associated with reduced arthritis incidence but more widespread tissue colonization and reduced clearance of bacterial DNA in multiple tissues including brain, heart, liver, lung and knee joint. B. burgdorferi uptake and killing were impaired in neutrophils isolated from hyperglycemic mice. Thus, attenuated neutrophil function in insulin-insufficient hyperglycemia was associated with reduced B. burgdorferi clearance in target organs. These data suggest that investigating the effects of comorbid conditions such as diabetes on outcomes of B. burgdorferi infections in humans may be warranted.

  14. Repressed Ca(2+) clearance in parthenolide-treated murine brain bEND.3 endothelial cells.

    Science.gov (United States)

    Tsai, Tien-Yao; Lou, Shyh-Liang; Cheng, Ka-Shun; Wong, Kar-Lok; Wang, Mei-Ling; Su, Tzu-Hui; Chan, Paul; Leung, Yuk-Man

    2015-12-15

    Parthenolide is a sesquiterpene lactone compound isolated from the leaves and flowerheads of the plant feverfew (Tanacetum parthenium). The anticancer effects of parthenolide have been well studied and this lactone compound is currently under clinical trials. Parthenolide is also a protective agent in cardiac reperfusion injury via its inhibition of nuclear factor-κB (NF-κB). Not much is known if this compound affects signal transduction in non-tumor cells. We investigated whether parthenolide affected Ca(2+) signaling in endothelial cells, key components in regulating the vascular tone. In this work using mouse cortical microvascular bEND.3 endothelial cells, we found that a 15-h treatment with parthenolide resulted in amplified ATP-triggered Ca(2+) signal; the latter had a very slow decay rate suggesting suppression of Ca(2+) clearance. Evidence suggests parthenolide suppressed Ca(2+) clearance by inhibiting the plasmalemmal Ca(2+) pump; such suppression did not result from decreased expression of the plasmalemmal Ca(2+) pump protein. Rather, such suppression was possibly a consequence of endoplasmic reticulum (ER) stress, since salubrinal (an ER stress protector) was able to alleviate parthenolide-induced Ca(2+) clearance suppression. Given the current deployment of parthenolide as an anti-cancer drug in clinical trials and the potential usage of this lactone as a cardioprotectant, it is important to examine in details the perturbing effects of parthenolide on Ca(2+) homeostasis in endothelial cells and neighboring vascular smooth muscle cells, activities of which exert profound effects on hemodynamics. PMID:26607466

  15. Stall Characteristics and Tip Clearance Effects in Forward Swept Axial Compressor Rotors

    Institute of Scientific and Technical Information of China (English)

    Ramakrishna PV; Govardhan M

    2009-01-01

    Tilting the blade sections to the flow direction (blade sweep) would increase the operating range of an axial com-pressor due to modifications in the pressure and velocity fields on the suction surface. On the other hand, blade tip gap, though finite, has great influence on the performance of a turbomachine. The present paper investigates the combined effect of these two factors on various flow characteristics in'a low speed axial flow compressor. For this present study, nine computational domains were modeled; three rotor sweep configurations (0°, 20° and 30°) and for three different clearance levels for each rotor. Commercial CFD solver ANSYS CFX 11.0 is used for the simulations. Results indicated that tip chordline sweep is found to improve the stall margin of the compressor by modifying the suction surface boundary layer migration phenomenon. Diffusion Factor (DF) contours showed the severity of stalling with unswept rotor. For the swept rotors, the zones of high probable stall are less severe and they become less in size with increasing sweep. Increment in the tip gap is found to gradually affect the perform-ance of unswept rotor, while the effect is very high for the two swept rotors for the earlier increments. As a mini-mum clearance is unavoidable, swept rotors suffer relatively higher deviation from the idealistic behavior than the unswept rotor due to tip clearance.

  16. Clearance of low levels of HCV viremia in the absence of a strong adaptive immune response

    Directory of Open Access Journals (Sweden)

    Manns Michael P

    2007-06-01

    Full Text Available Abstract Spontaneous clearance of hepatitis C virus (HCV has frequently been associated with the presence of HCV-specific cellular immunity. However, there had been also reports in chimpanzees demonstrating clearance of HCV-viremia in the absence of significant levels of detectable HCV-specific cellular immune responses. We here report seven asymptomatic acute hepatitis C cases with peak HCV-RNA levels between 300 and 100.000 copies/ml who all cleared HCV-RNA spontaneously. Patients were identified by a systematic screening of 1176 consecutive new incoming offenders in a German young offender institution. Four of the seven patients never developed anti-HCV antibodies and had normal ALT levels throughout follow-up. Transient weak HCV-specific CD4+ T cell responses were detectable in five individuals which did not differ in strength and breadth from age- and sex-matched patients with chronic hepatitis C and long-term recovered patients. In contrast, HCV-specific MHC-class-I-tetramer-positive cells were found in 3 of 4 HLA-A2-positive patients. Thus, these cases highlight that clearance of low levels of HCV viremia is possible in the absence of a strong adaptive immune response which might explain the low seroconversion rate after occupational exposure to HCV.

  17. Low-cost FM oscillator for capacitance type of blade tip clearance measurement system

    Science.gov (United States)

    Barranger, John P.

    1987-01-01

    The frequency-modulated (FM) oscillator described is part of a blade tip clearance measurement system that meets the needs of a wide class of fans, compressors, and turbines. As a result of advancements in the technology of ultra-high-frequency operational amplifiers, the FM oscillator requires only a single low-cost integrated circuit. Its carrier frequency is 42.8 MHz when it is used with an integrated probe and connecting cable assembly consisting of a 0.81 cm diameter engine-mounted capacitance probe and a 61 cm long hermetically sealed coaxial cable. A complete circuit analysis is given, including amplifier negative resistance characteristics. An error analysis of environmentally induced effects is also derived, and an error-correcting technique is proposed. The oscillator can be calibrated in the static mode and has a negative peak frequency deviation of 400 kHz for a rotor blade thickness of 1.2 mm. High-temperature performance tests of the probe and 13 cm of the adjacent cable show good accuracy up to 600 C, the maximum permissible seal temperature. The major source of error is the residual FM oscillator noise, which produces a clearance error of + or - 10 microns at a clearance of 0.5 mm. The oscillator electronics accommodates the high rotor speeds associated with small engines, the signals from which may have frequency components as high as 1 MHz.

  18. Preliminary Diffusive Clearance of Silicon Nanopore Membranes in a Parallel Plate Configuration for Renal Replacement Therapy.

    Science.gov (United States)

    Kim, Steven; Heller, James; Iqbal, Zohora; Kant, Rishi; Kim, Eun Jung; Durack, Jeremy; Saeed, Maythem; Do, Loi; Hetts, Steven; Wilson, Mark; Brakeman, Paul; Fissell, William H; Roy, Shuvo

    2016-01-01

    Silicon nanopore membranes (SNMs) with compact geometry and uniform pore size distribution have demonstrated a remarkable capacity for hemofiltration. These advantages could potentially be used for hemodialysis. Here, we present an initial evaluation of the SNM's mechanical robustness, diffusive clearance, and hemocompatibility in a parallel plate configuration. Mechanical robustness of the SNM was demonstrated by exposing membranes to high flows (200 ml/min) and pressures (1,448 mm Hg). Diffusive clearance was performed in an albumin solution and whole blood with blood and dialysate flow rates of 25 ml/min. Hemocompatibility was evaluated using scanning electron microscopy and immunohistochemistry after 4 hours in an extracorporeal porcine model. The pressure drop across the flow cell was 4.6 mm Hg at 200 ml/min. Mechanical testing showed that SNM could withstand up to 775.7 mm Hg without fracture. Urea clearance did not show an appreciable decline in blood versus albumin solution. Extracorporeal studies showed blood was successfully driven via the arterial-venous pressure differential without thrombus formation. Bare silicon showed increased cell adhesion with a 4.1-fold increase and 1.8-fold increase over polyethylene glycol (PEG)-coated surfaces for tissue plasminogen factor (t-PA) and platelet adhesion (CD41), respectively. These initial results warrant further design and development of a fully scaled SNM-based parallel plate dialyzer for renal replacement therapy.

  19. Influence of initial lung deposit on pulmonary clearance after plutonium oxide inhalation in rat

    International Nuclear Information System (INIS)

    Alveolar macrophages are a key element in the clearance of inhaled particles after phagocytosis, and thus participate actively in lung dose distribution and in the risk of tumour formation. We studied the influence of initial lung deposit (ILD) on lung clearance and distribution of activity from 3 d to 3 months after inhalation of two forms of PuO2 (97% 239Pu and 70% 239Pu) in rats. ILDs ranging from 2.1 to 17 kBq were used. The total activity measured using X-ray spectrometry 3 months post-inhalation, relative to the ILD, showed a similar decrease in all groups, with the remaining activity representing ∼30% of the ILD. The total activity recovered in bronchoalveolar lavages represented ∼60% of the total lung activity. This ratio remained stable over time for the lowest ILD tested but decreased for higher ILD. In addition, the percentage of macrophages associated with particles decreased faster with time in rats with the highest ILD. Under our experimental conditions, there were no marked differences in lung clearance between groups. However, the distribution of the activity seems to vary with the time post-exposure between low and high ILD. (authors)

  20. Non-cytolytic antigen clearance in DNA-vaccinated mice with electropotation

    Institute of Scientific and Technical Information of China (English)

    Jin-liang PENG; Yong-gang ZHAO; Jun-hua MAI; Wen-ka PANG; Wei GUO; Guang-ming CHEN; Guo-yu MO; Gui-rong RAO; Yu-hong XU

    2007-01-01

    Aim: To explore the potential of electroporation (EP)-mediated hepatitis B virus (HBV) DNA vaccination for the treatment of chronic HBV infection. Methods: BALB/c mice were vaccinated with HBV DNA vaccine encoding for the HBV preS2-S antigen, combined with or without EP. HBV surface antigen expression plasmid was administered into mice liver via a hydrodynamic injection to mimic HBV infection. The clearance of antigen in the serum and liver was detected by ELISA assay and immunohistochemical staining. The histopathology of the liver tissues was examined by HE staining and serum alanine aminotransferase assay.Results: The immunogenicity ofHBV DNA vaccine encoding for the HBV preS2-S antigen can be improved by EP-mediated vaccine delivery. The elicited immune responses can indeed reduce the expression of HBV surface antigen (HBsAg) in hepatocytes of the mouse model that was transfected to express HBsAg using the hydrodynamic injection method. The antigen clearance process did not cause significant toxicity to liver tissue, suggesting a non-cytolytic mechanism. Conclusion: The EP-aided DNA vaccination may have potential in mediating viral clearance in chronic hepatitis B patients.

  1. Loss of Acetylcholine Signaling Reduces Cell Clearance Deficiencies in Caenorhabditis elegans.

    Science.gov (United States)

    Pinto, Sérgio M; Almendinger, Johann; Cabello, Juan; Hengartner, Michael O

    2016-01-01

    The ability to eliminate undesired cells by apoptosis is a key mechanism to maintain organismal health and homeostasis. Failure to clear apoptotic cells efficiently can cause autoimmune diseases in mammals. Genetic studies in Caenorhabditis elegans have greatly helped to decipher the regulation of apoptotic cell clearance. In this study, we show that the loss of levamisole-sensitive acetylcholine receptor, but not of a typical neuronal acetylcholine receptor causes a reduction in the number of persistent cell corpses in worms suffering from an engulfment deficiency. This reduction is not caused by impaired or delayed cell death but rather by a partial restoration of the cell clearance capacity. Mutants in acetylcholine turn-over elicit a similar phenotype, implying that acetylcholine signaling is the process responsible for these observations. Surprisingly, tissue specific RNAi suggests that UNC-38, a major component of the levamisole-sensitive receptor, functions in the dying germ cell to influence engulfment efficiency. Animals with loss of acetylcholine receptor exhibit a higher fraction of cell corpses positive for the "eat-me" signal phosphatidylserine. Our results suggest that modulation by ion channels of ion flow across plasma membrane in dying cells can influence the dynamics of phosphatidylserine exposure and thus clearance efficiency.

  2. Passing through the renal clearance barrier: toward ultrasmall sizes with stable ligands for potential clinical applications

    Directory of Open Access Journals (Sweden)

    Zhang XD

    2014-04-01

    Full Text Available Xiao-Dong Zhang,1 Jiang Yang,2 Sha-Sha Song,1 Wei Long,1 Jie Chen,1 Xiu Shen,1 Hao Wang,1 Yuan-Ming Sun,1 Pei-Xun Liu,1 Saijun Fan11Tianjin Key Laboratory of Molecular Nuclear Medicine, Institute of Radiation Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, People's Republic of China; 2Department of Biological Systems Engineering, University of Wisconsin-Madison, Madison, WI, USAAbstract: The use of nanoparticles holds promise for medical applications, such as X-ray imaging, photothermal therapy and radiotherapy. However, the in vivo toxicity of inorganic nanoparticles raises some concern regarding undesirable side effects which prevent their further medical application. Ultrasmall sub-5.5 nm particles can pass through the barrier for renal clearance, minimizing their toxicity. In this letter we address some recent interesting work regarding in vivo toxicity and renal clearance, and discuss the possible strategy of utilizing ultrasmall nanomaterials. We propose that small hydrodynamic sized nanoclusters can achieve both nontoxic and therapeutic clinical features.Keywords: in vivo clearance, gold nanoparticles, small size

  3. Nonlinear Dynamics Behaviors of a Rotor Roller Bearing System with Radial Clearances and Waviness Considered

    Institute of Scientific and Technical Information of China (English)

    Wang Liqin; Cui Li; Zheng Dezhi; Gu Le

    2008-01-01

    A rotor system supported by roller bearings displays very complicated nonlinear behaviors due to nonlinear Hertzian contact forces, radial clearances and bearing waviness. This paper presents nonlinear bearing forces of a roller bearing under four-dimensional loads and establishes 4-DOF dynamics equations of a rotor roller bearing system. The methods of Newmark-β and of Newton-Laphson are used to solve the nonlinear equations. The dynamics behaviors of a rigid rotor system are studied through the bifurcation, the Poincar bility caused by the quasi-periodic bifurcation, the periodic-doubling bifurcation and chaos routes as the rotational speed increases.Clearances, outer race waviness, inner race waviness, roller waviness, damping, radial forces and unbalanced forces-all these bring a significant influence to bear on the system stability. As the clearance increases, the dynamics behaviors become complicated with the number and the scale of instable regions becoming larger. The vibration frequencies induced by the roller bearing waviness and the orders of the waviness might cause severe vibrations. The system is able to eliminate non-periodic vibration by reasonable choice and optimization of the parameters.

  4. Preliminary Diffusive Clearance of Silicon Nanopore Membranes in a Parallel Plate Configuration for Renal Replacement Therapy.

    Science.gov (United States)

    Kim, Steven; Heller, James; Iqbal, Zohora; Kant, Rishi; Kim, Eun Jung; Durack, Jeremy; Saeed, Maythem; Do, Loi; Hetts, Steven; Wilson, Mark; Brakeman, Paul; Fissell, William H; Roy, Shuvo

    2016-01-01

    Silicon nanopore membranes (SNMs) with compact geometry and uniform pore size distribution have demonstrated a remarkable capacity for hemofiltration. These advantages could potentially be used for hemodialysis. Here, we present an initial evaluation of the SNM's mechanical robustness, diffusive clearance, and hemocompatibility in a parallel plate configuration. Mechanical robustness of the SNM was demonstrated by exposing membranes to high flows (200 ml/min) and pressures (1,448 mm Hg). Diffusive clearance was performed in an albumin solution and whole blood with blood and dialysate flow rates of 25 ml/min. Hemocompatibility was evaluated using scanning electron microscopy and immunohistochemistry after 4 hours in an extracorporeal porcine model. The pressure drop across the flow cell was 4.6 mm Hg at 200 ml/min. Mechanical testing showed that SNM could withstand up to 775.7 mm Hg without fracture. Urea clearance did not show an appreciable decline in blood versus albumin solution. Extracorporeal studies showed blood was successfully driven via the arterial-venous pressure differential without thrombus formation. Bare silicon showed increased cell adhesion with a 4.1-fold increase and 1.8-fold increase over polyethylene glycol (PEG)-coated surfaces for tissue plasminogen factor (t-PA) and platelet adhesion (CD41), respectively. These initial results warrant further design and development of a fully scaled SNM-based parallel plate dialyzer for renal replacement therapy. PMID:26692401

  5. In vivo biocompatibility, clearance, and biodistribution of albumin vehicles for pulmonary drug delivery.

    Science.gov (United States)

    Woods, A; Patel, A; Spina, D; Riffo-Vasquez, Y; Babin-Morgan, A; de Rosales, R T M; Sunassee, K; Clark, S; Collins, H; Bruce, K; Dailey, L A; Forbes, B

    2015-07-28

    The development of clinically acceptable albumin-based nanoparticle formulations for use in pulmonary drug delivery has been hindered by concerns about the toxicity of nanomaterials in the lungs combined with a lack of information on albumin nanoparticle clearance kinetics and biodistribution. In this study, the in vivo biocompatibility of albumin nanoparticles was investigated following a single administration of 2, 20, and 390μg/mouse, showing no inflammatory response (TNF-α and IL-6, cellular infiltration and protein concentration) compared to vehicle controls at the two lower doses, but elevated mononucleocytes and a mild inflammatory effect at the highest dose tested. The biodistribution and clearance of (111)In labelled albumin solution and nanoparticles over 48h following a single pulmonary administration to mice was investigated by single photon emission computed tomography and X-ray computed tomography imaging and terminal biodistribution studies. (111)In labelled albumin nanoparticles were cleared more slowly from the mouse lung than (111)In albumin solution (64.1±8.5% vs 40.6±3.3% at t=48h, respectively), with significantly higher (P24h indicating that small amounts of activity were cleared from the lungs both by translocation across the lung mucosal barrier, as well as mucociliary clearance. This study provides important information on the fate of albumin vehicles in the lungs, which may be used to direct future formulation design of inhaled nanomedicines.

  6. Hyperglycemia Impairs Neutrophil-Mediated Bacterial Clearance in Mice Infected with the Lyme Disease Pathogen

    Science.gov (United States)

    Javid, Ashkan; Zlotnikov, Nataliya; Pětrošová, Helena; Tang, Tian Tian; Zhang, Yang; Bansal, Anil K.; Ebady, Rhodaba; Parikh, Maitry; Ahmed, Mijhgan; Sun, Chunxiang; Newbigging, Susan; Kim, Yae Ram; Santana Sosa, Marianna; Glogauer, Michael

    2016-01-01

    Insulin-insufficient type 1 diabetes is associated with attenuated bactericidal function of neutrophils, which are key mediators of innate immune responses to microbes as well as pathological inflammatory processes. Neutrophils are central to immune responses to the Lyme pathogen Borrelia burgdorferi. The effect of hyperglycemia on host susceptibility to and outcomes of B. burgdorferi infection has not been examined. The present study investigated the impact of sustained obesity-independent hyperglycemia in mice on bacterial clearance, inflammatory pathology and neutrophil responses to B. burgdorferi. Hyperglycemia was associated with reduced arthritis incidence but more widespread tissue colonization and reduced clearance of bacterial DNA in multiple tissues including brain, heart, liver, lung and knee joint. B. burgdorferi uptake and killing were impaired in neutrophils isolated from hyperglycemic mice. Thus, attenuated neutrophil function in insulin-insufficient hyperglycemia was associated with reduced B. burgdorferi clearance in target organs. These data suggest that investigating the effects of comorbid conditions such as diabetes on outcomes of B. burgdorferi infections in humans may be warranted. PMID:27340827

  7. Repetitive,Low—dose Tissue Plasminogen Activator for Clearance of Experimental Vitreous Hemorrhage

    Institute of Scientific and Technical Information of China (English)

    PeiquanZhao; WenjiWang

    1995-01-01

    Purpose:To investigate the effectiveness of repetitve,low-dose tPA for clearance of experimental vitreous hemorhage,Methods:The model vitreous hemorrhage was produced by intravitreal injection of 0.05ml of autologous citrated whole blood in 14rabbits(28eyes).One week after the creation of vitreous hemorrhage,the eyes were randomly separated into 3groups.Groups 1and 2received two injections of 5or 25μg of tPA,respective-ly,with one injection in a7-day interval.Group 3reeived two injections of PS in thesame way.Results;The clearance of vitreous hemorrhage in rPA-treated groups was signifi-cantly faster than that in the control group(P<0.05,orP<0.01).However,there was no statistically significant difference between the two tPA-treated groups.Not any retinal toxicity was detected by ERG,light microscopy,and transmission electron microscopy examinations.Conclusions:repetitive injections of low-dose tPA were effective in the treatment of experimental vitreous hemorrhage.Whether it is effective on the clearance of vitreous hemorrhage in human eyes needs further investigation.

  8. FGF21-Mediated Improvements in Glucose Clearance Require Uncoupling Protein 1

    Directory of Open Access Journals (Sweden)

    Michelle M. Kwon

    2015-11-01

    Full Text Available Fibroblast growth factor 21 (FGF21-mediated weight loss and improvements in glucose metabolism correlate with increased uncoupling protein 1 (Ucp1 levels in adipose tissues, suggesting that UCP1-dependent thermogenesis may drive FGF21 action. It was reported that FGF21 is equally effective at reducing body weight and improving glucose homeostasis without UCP1. We find while FGF21 can lower body weight in both wild-type and Ucp1 knockout mice, rapid clearance of glucose by FGF21 is defective in the absence of UCP1. Furthermore, in obese wild-type mice there is a fall in brown adipose tissue (BAT temperature during glucose excursion, and FGF21 improves glucose clearance while preventing the fall in BAT temperature. In Ucp1 knockout mice, the fall in BAT temperature during glucose excursion and FGF21-mediated changes in BAT temperature are lost. We conclude FGF21-mediated improvements in clearance of a glucose challenge require UCP1 and evoke UCP1-dependent thermogenesis as a method to increase glucose disposal.

  9. Influence of saw blade clearance over the workpiece on tool-wear

    Directory of Open Access Journals (Sweden)

    Mikuláš Siklienka

    2008-12-01

    Full Text Available This paper presents the results of experimental measurement of tool-wear in the cutting process with circular saw of oak wood depending on the upper clearance of 5mmand 50 mm, respectively. The circular saw blade made of HSS by Pilana was used for the experiment. The measurement was carried out by the experimental equipment designed by the Department of Woodworking, Technical University of Zvolen and DMMA–36 circular saw made by Reszelski Zaklad Przemyslu Leoenictwa in Reszel. The tool-wear was evaluated by two parameters and namely by the radius of the cutting edge rn and by the cutting edge recession SV. The results of tool-wear are presented in dependence on the indicated chip length and cutting material length. With the change of the clearance from 5 mm to 50 mm and with the thickness of the test specimen h = 30 mm almost double amount of sawn wood is required to attain the same chip length. The results have shown that in dependence on the length of the cutting material, the tool wear is smaller at a higher clearance of saw blade over the workpiece.

  10. Impairment of exogenous lactate clearance in experimental hyperdynamic septic shock is not related to total liver hypoperfusion

    NARCIS (Netherlands)

    P. Tapia (Pablo); D. Soto (Dagoberto); A. Bruhn (Alejandro); L. Alegría (Leyla); N. Jarufe (Nicolás); C. Luengo (Cecilia); E. Kattan (Eduardo); T. Regueira (Tomas); A. Meissner (Arturo); R. Menchaca (Rodrigo); M.I. Vives (María Ignacia); N. Echeverría (Nicolas); G.A. Ospina-Tascon (Gustavo A); J. Bakker (Jan); G. Hernandez (Glenn)

    2015-01-01

    textabstractIntroduction: Although the prognostic value of persistent hyperlactatemia in septic shock is unequivocal, its physiological determinants are controversial. Particularly, the role of impaired hepatic clearance has been underestimated and is only considered relevant in patients with liver

  11. Lithium clearance and renal tubular sodium handling during acute and long-term nifedipine treatment in essential hypertension

    DEFF Research Database (Denmark)

    Bruun, N E; Ibsen, H; Skøtt, P;

    1988-01-01

    1. In two separate studies the lithium clearance method was used to evaluate the influence of acute and long-term nifedipine treatment on renal tubular sodium reabsorption. 2. In the acute study, after a 4 week placebo period two doses of 20 mg of nifedipine decreased supine blood pressure from 155...... of nifedipine treatment. As compared with placebo, mean supine blood pressure decreased significantly. The glomerular filtration rate did not change but lithium clearance fell by 30%. Consequently, the absolute and the fractional proximal sodium reabsorption increased significantly. The fractional distal sodium...... reabsorption did not change. Sodium clearance, fractional sodium excretion, potassium clearance, plasma volume and extracellular fluid volume were also unchanged. 4. In conclusion, we found no changes of renal tubular sodium reabsorption during acute nifedipine treatment, whereas long-term nifedipine treatment...

  12. A STUDY ON EGFR, CREATININE CLEARANCE & URINARY PROTEIN TO CREATININE RATIO IN CKD

    Directory of Open Access Journals (Sweden)

    Ganga Bhavani

    2014-05-01

    Full Text Available There was a good correlation between Glomerular Filtration Rate (GFR values estimated by any of the 3 methods. Crcl correlated better with Cockcroft-Gault (CG eGFR than Modification of Diet in Renal Disease (MDRD eGFR and there was also a very good correlation between CG eGFR and MDRD eGFR. Based on this result we feel that in advanced CKD all 3 methods give similar GFR estimates but in earlier stages of Chronic Kidney Disease (CKD Creatinine clearance (Crcl gives higher estimate of GFR. Thus use of Crcl may wrongly classify patients into less severe stages of CKD which might lead to delay in initiation of proper treatment. MATERIALS AND METHODS: CKD patients were selected on the basis of serum creatinine levels. S.C > 2.5 mg/dl values were considered to be having CKD. 75 Samples were tested. Both males & females patients are taken in this study. Serum Creatinine & Urinary Creatinine by Jaffe’s method, Blood Urea by Urease method, Urinary Protein by Pyrogallol red method, estimation of GFR by three methods. Creatinine Clearance &eGFR by using Cockcroft- Gault& MDRD equations. RESULT: A total of 75 patients attending the nephrology department (P.E.S Medical College, Kuppamfor treatment and monitoring for chronic kidney disease where included in the present study. Serum creatinine, serum urea and creatinine clearance were measured in all these patients as per methods described under materials and methods. Estimated GFR (eGFR using CG (Cock croft and MDRD (Modification of Diet in renal disease formulae were calculated. Majority of the cases were complications due to long standing diabetes mellitus or hypertension. CONCLUSION: Creatinine Clearance over estimates GFR in early stages of CKD. Use of Crcl to assess GFR may not be proper to classify CKD into different stages. Any of the 3 methods (Crcl, CG eGFR and MDRD eGFR can be used as markers of GFR in advanced stages of CKD. MDRD eGFR is a better indicator of eGFR for staging CKD in early stages

  13. Plasma clearance of cadmium and zinc in non-acclimated and metal-acclimated trout

    Energy Technology Data Exchange (ETDEWEB)

    Chowdhury, M. Jasim; Grosell, M.; McDonald, D.G.; Wood, C.M

    2003-08-20

    Adult rainbow trout were pre-exposed to a sublethal concentration of waterborne cadmium (Cd, 26.7 nmol/l) or waterborne zinc (Zn, 2294 nmol/l) for 30 days to induce acclimation. A single dose of radiolabeled Cd (64.4 nmol/kg) or Zn (183.8 nmol/kg) was injected into the vascular system of non-acclimated and Cd- or Zn-acclimated trout through indwelling arterial catheters. Subsequently, repetitive blood samples over 10 h and terminal tissue samples (liver, heart, bile, stomach, intestine, kidney, gills, muscle, and spleen) were taken to characterize the effect of metal acclimation on clearance kinetics in vivo. Plasma clearance of Cd in Cd-acclimated fish (0.726{+-}0.015 and 0.477{+-}0.012 ml/min per kg for total and newly accumulated Cd, respectively), was faster than that in non-acclimated trout (0.493{+-}0.013 and 0.394{+-}0.009 ml/min per kg). Unlike plasma Cd, the levels of Cd in red blood cells (RBCs) were 1.2-2.2 times higher in Cd-acclimated fish than in non-acclimated fish. At 10 h post-injection, the liver accumulated the highest proportion ({approx}22%) of the injected Cd dose in both non-acclimated and Cd-acclimated fish but did not account for the difference in plasma levels of Cd between two groups. Plasma clearance of Zn ({approx}0.23 ml/min per kg for new Zn) was substantially lower than Cd clearance. Pre-acclimation to waterborne Zn reduced the new Zn levels in RBCs, but did not affect the clearance of Zn from blood plasma or tissue burdens of Zn in fish. Bile concentrations of both Cd and Zn were elevated in acclimated fish, but total bile burden accounted for <1% of the injected metal dose. The results suggest that the detoxification process of injected plasma Cd is stimulated by pre-acclimation to waterborne Cd, and that Zn levels are homeostatically controlled in both non-acclimated and acclimated trout.

  14. Evaluation of circulating levels and renal clearance of natural amino acids in patients with Cushing's disease.

    Science.gov (United States)

    Faggiano, A; Pivonello, R; Melis, D; Alfieri, R; Filippella, M; Spagnuolo, G; Salvatore, F; Lombardi, G; Colao, A

    2002-02-01

    Although the hypercortisolism-induced impairment of protein homeostasis is object of several studies, a detailed evaluation of the complete amino acid profile of patients with Cushing's syndrome (CS) has never been performed. The aim of the current open transversal controlled study was to evaluate serum and urinary concentrations as well as renal clearance of the complete series of natural amino acids and their relationship with glucose tolerance in patients with Cushing's disease (CD). Twenty patients with CD (10 active and 10 cured) and 20 sex- and age-matched healthy controls entered the study. Measurement of serum and urinary levels of the complete series of natural amino acids was performed in all patients analyzed by cationic exchange high performance liquid cromatography (HPLC) after 2 weeks of a standardized protein intake regimen. The renal clearance (renal excretion rate) of each amino acid was calculated on the basis of the serum and urinary concentrations of creatinine and the specific amino acid. Fasting glucose and insulin levels, glucose and insulin response to standard glucose load, insulinogenic and homeostasis model insulin resistance (Homa-R) indexes were also evaluated and correlated to the circulating levels and renal clearances of each amino acid. Significantly higher serum (p<0.01) and urinary (p<0.05) levels of alanine and cystine, lower serum and higher urinary levels of leucine, isoleucine and valine (p<0.05) and higher renal excretion rates of leucine, isoleucine and valine (p<0.01) were found in patients with active CD than in patients cured from the disease and in controls. No difference was found between cured patients and controls. Creatinine clearance was similar in active and cured patients and in controls. In patients with active CD, urinary cortisol levels were significantly correlated to urinary cystine levels (r=0.85; p<0.01) and renal excretion rate of leucine (r=-0.76; p<0.05), isoleucine (r=-0.76; p<0.05) and valine (r=-0

  15. The influence of clearance on friction, lubrication and squeaking in large diameter metal-on-metal hip replacements

    OpenAIRE

    Brockett, CL; Harper, P; Williams, S.; Isaac, GH; Dwyer-Joyce, RS; Jin, Z; Fisher, J

    2008-01-01

    Large diameter metal-on-metal bearings (MOM) are becoming increasingly popular, addressing the needs of young and more active patients. Clinical data has shown excellent short-to-mid-term results, though incidences of transient squeaking have been noted between implantation and up to 2 years post-operative. Geometric design features, such as clearance, have been significant in influencing the performance of the bearings. Sets of MOM bearings with different clearances were investigated in this...

  16. Effects of a Nonuniform Tip Clearance Profile on the Performance and Flow Field in a Centrifugal Compressor

    OpenAIRE

    Yohan Jung; Minsuk Choi; Seonghwan Oh; Jehyun Baek

    2012-01-01

    This paper presents a numerical investigation of the effects of a nonuniform tip clearance profile on the performance and flow field in a centrifugal compressor with a vaneless diffuser. This study focuses in particular on the magnitude and location of the wake. Six impellers with different tip clearance profiles were tested in the flow simulations. The accuracy of the numerical simulations was assessed by comparing the experimental data with the computational results for a system characteriz...

  17. COMPARISON OF TWO METHODS TO INCREASE TIP CLEARANCE AND ITS EFFECT ON PERFORMANCE OF TURBOCHARGER CENTRIFUGAL COMPRESSOR STAGE

    Institute of Scientific and Technical Information of China (English)

    SYED Noman Danish; MA Chaochen; YANG Ce; L(U) Wei

    2007-01-01

    Tip clearance between the blade tip and casing of a centrifugal compressor can be varied through two methods: by changing the blade height (M1) or by changing the casing diameter (M2). Numerical simulations are carried out to compare these two methods and their effect on the stage and impeller performance. The impeller and diffuser are connected through rotor Stator boundary using frozen rotor approach. Overall stage performance and the flow configuration have been investigated for nine tip clearance levels from no gap to 1 mm. Impeller and diffuser performances are also presented separately. It has been found that the overall and impeller performance are comparatively better for Ml below tip clearance of 0.5 mm whereas M2 is found advantageous above 0.5 mm of tip clearance. Both M1 and M2 show performance degradation with the increase in tip clearance. Two models have been proposed for the stage total pressure ratio and efficiency, which are found to be in agreement with experimental results. The impeller efficiency and the pressure ratio are found to be maximum at tip clearance of 0.1 mm for both the cases however minimum diffuser effectiveness is also observed at the same clearance level. Diffuser effectiveness is found to be maximum at zero gap for both cases. As it is practically impossible to have zero gap for unshrouded impellers so it is concluded that the Optimum thickness is 0.5 mm onwards for Ml and 0.5 mm for M2 in terms of diffuser effectiveness. Mass averaged flow parameters, entropy, blade loading diagram and relative pressure fields are presented, showing the loss production within the impeller passage with tip clearance.

  18. Effects of terbutaline sulphate aerosol on bronchodilator response and lung mucociliary clearance in patients with mild stable asthma.

    OpenAIRE

    Bateman, J. R.; Pavia, D; Sheahan, N F; Newman, S P; Clarke, S W

    1983-01-01

    Ventilatory function and whole lung mucociliary clearance have been assessed in 10 patients with mild stable asthma following inhalation of 1 mg of the beta-adrenergic receptor agonist terbutaline sulphate (Bricanyl, Astra Pharmaceuticals) from a metered dose inhaler (MDI). Compared to placebo inhalation, terbutaline produced marked bronchodilatation (mean percentage increase in FEV1 14%, P less than 0.01). Mucociliary clearance (measured by the in vivo radioaerosol technique) was assessed on...

  19. Intravascular clearance of disseminating Cryptococcus neoformans in the brain can be improved by enhancing neutrophil recruitment in mice.

    Science.gov (United States)

    Sun, Donglei; Zhang, Mingshun; Liu, Gongguan; Wu, Hui; Li, Chang; Zhou, Hong; Zhang, Xiquan; Shi, Meiqing

    2016-07-01

    Extrapulmonary dissemination of Cryptococcus neoformans (C. neoformans) is one of the most critical steps in the development of meningoencephalitis. Here, we report that clearance of the disseminating C. neoformans occurs within the brain microvasculature. Interestingly, the efficiency of the intravascular clearance in the brain is reduced compared to that in the lung. Intravascular clearance is mainly mediated by neutrophils, and complement C5a receptor signaling is crucial for mediating neutrophil recruitment in the vasculature. C. neoformans stimulated actin polymerization of neutrophils is critically involved in their recruitment to the lung, which is associated with the unique vascular structure detected in the lung. The relatively lower efficiency of fungal clearance in the brain vasculature correlates with less efficient recruitment of neutrophils. Accordingly, intravascular clearance of C. neoformans in the brain could be remarkably improved by increasing the recruitment of neutrophils. We conclude that neutrophils have the ability to eliminate C. neoformans arrested in the vasculature. However, insufficient recruitment of neutrophils limited the optimal clearance of this microorganism in the brain. These results imply that a therapeutic strategy aimed at enhancing the accumulation of neutrophils could help prevent cryptococcal meningoencephalitis. PMID:27109176

  20. The measurement of skin lymph flow by isotope clearance--reliability, reproducibility, injection dynamics, and the effect of massage

    International Nuclear Information System (INIS)

    The measurement of skin lymph flow was investigated using an isotope clearance technique (ICT). Multiple lymph flow determinations were undertaken in the skin of anaesthetized large white pigs to test for reproducibility, ascertain the most suitable tracer, study the influence of injection dynamics, and observe the effect of massage as a stimulus to lymph flow. Blood clearance of tracer was also investigated. Results demonstrated that lymphatic clearance is a monoexponential function with good reproducibility under controlled laboratory conditions. 99mTc-colloid (TCK17 Cis) compared favorably with 131I-human serum albumin as a tracer and both performed better than colloid gold (198Au). Lymph flow was significantly faster in one pig than in the other. No difference existed between left and right sides or between caudal and rostral sites on each flank, but clearance was significantly slower in thigh than flank skin. Sub-epidermal injections cleared faster and more consistently than either deep or subcutaneous injections. Neither injection volume nor needle tract backflow of tracer influenced results, but local massage significantly enhanced clearance. Escape of 99mTc-colloid by the blood was negligible. These results indicate that skin lymph flow can be reliably measured when conditions are controlled. Extrinsic factors such as massage strongly influence lymph flow. Greater sensitivity in detecting degrees of lymphatic insufficiency may be achieved if a standardized stimulus to lymph flow is administered during isotope clearance measurement

  1. Research on the effect of wear-ring clearances to the axial and radial force of a centrifugal pump

    Science.gov (United States)

    Zhao, W. G.; Y He, M.; Qi, C. X.; Li, Y. B.

    2013-12-01

    Varying of the wear-ring clearance not only has a distinct effect on the volumetric loss of the centrifugal pump, but also on the performance of the centrifugal pump including the axial and radial forces. Comparing with the experimental studies, numerical simulation methods have some special advantages, such as the low cost, fast and high efficiency, and convenient to get the detailed structure of the internal flow characteristics, so it has been widely used in the fluid machinery study in recent years. In order to study the effect of wear-ring clearance on the force performance of the centrifugal pump, based on the Reynolds Time-Averaged N-S equations and RNG k-ε turbulence model, a centrifugal pump with three variable styles of the wear-rings was simulated: Only the clearance of the front wear-ring was changed, only the clearance of the back wear-ring was changed and both were changed. Comparing with the experiment, numerical results show a good agreement. In the three changing styles of the clearance, the variable of the clearance of front wear-ring has the most influence on the axial force of the centrifugal pump, while has tiny effect on the radial force for all the conditions.

  2. Snow clearance

    CERN Multimedia

    Mauro Nonis

    2005-01-01

    In reply to the numerous questions received, we should like to inform you of the actions and measures taken in an effort to maintain the movements of vehicles and pedestrians since the heavy snow fall on Sunday 23 January. Our contractor's employees began clearing the snow during the morning of Sunday 23 January on the main CERN sites (Meyrin, Prévessin), but an accident prevented them from continuing. The vehicle in question was repaired by Monday morning when two other vehicles joined it to resume snow clearing; priority was given to access points to the main sites and the LHC sites, as well as to the main roads inside the sites. The salt sprinklers were also brought into action that same day; the very low temperature during the night from Monday to Tuesday prevented the snow from melting and compacted the ice; the continuing cold during the day on Tuesday (-6°C at 10:00 on the Meyrin site) meant that all efforts to remove the ice were doomed to failure. In order to ensure more efficie...

  3. Conventional measurements of GFR using {sup 51}Cr-EDTA overestimate true renal clearance by 10 percent

    Energy Technology Data Exchange (ETDEWEB)

    Moore, Amelia E.B.; Park-Holohan, So-Jin; Blake, Glen M.; Fogelman, Ignac [Department of Nuclear Medicine, Guy' s Hospital, St Thomas Street, London, SE1 9RT (United Kingdom)

    2003-01-01

    It is widely believed that measurement of the area under the plasma clearance curve (AUC) following a single intravenous injection of chromium-51 labelled ethylene diamine tetra-acetic acid ({sup 51}Cr-EDTA) is a gold standard method for determining glomerular filtration rate (GFR). However, there are reports that {sup 51}Cr-EDTA may have a significant extrarenal clearance. The aim of this study was to identify the non-renal component of {sup 51}Cr-EDTA plasma clearance contributing to the AUC measurement of GFR. Seventy healthy postmenopausal women (mean age 60 years, range 45-79 years) were injected with 3 MBq {sup 51}Cr-EDTA and 0.25 MBq iodine-125 labelled human serum albumin and 11 blood samples taken between 0 and 4 h through an indwelling venous cannula. For the first 21 subjects, two complete urine collections were made 0-2 h and 2-4 h after injection, and for the final 49 patients, four 1-h urine collections were made. The mean {sup 51}Cr-EDTA total plasma clearance was 84 ml/min (range 50-132 ml/min). The mean ratio (SEM) of urine to total clearance determined from the cumulative 1-, 2-, 3- and 4-h data was 0.903 (0.018), 0.891 (0.013), 0.898 (0.011) and 0.899 (0.010) respectively and remained constant despite the mean urine concentration decreasing from 122% to 15%/litre during this period. A least squares fit to data from the 238 individual urine collections was used to determine the fraction of the total plasma clearance attributable to renal clearance, {alpha}{sub 0}, and the residual urine volume, {delta}V. The results were {alpha}{sub 0}=0.910 (95% CI: 0.889-0.932) and {delta}V=14 ml (95% CI: -4 to +34 ml). The overestimation of the true renal clearance of {sup 51}Cr-EDTA by the AUC method is believed to be due to the failure of the plasma clearance curve to reach the true terminal exponential by 2 h after injection as usually assumed. As a result, conventional measurements of GFR using {sup 51}Cr-EDTA overestimate the true renal clearance of tracer

  4. Delayed parasite clearance after treatment with dihydroartemisinin-piperaquine in Plasmodium falciparum malaria patients in central Vietnam.

    Science.gov (United States)

    Thriemer, Kamala; Hong, Nguyen Van; Rosanas-Urgell, Anna; Phuc, Bui Quang; Ha, Do Manh; Pockele, Evi; Guetens, Pieter; Van, Nguyen Van; Duong, Tran Thanh; Amambua-Ngwa, Alfred; D'Alessandro, Umberto; Erhart, Annette

    2014-12-01

    Reduced susceptibility of Plasmodium falciparum toward artemisinin derivatives has been reported from the Thai-Cambodian and Thai-Myanmar borders. Following increasing reports from central Vietnam of delayed parasite clearance after treatment with dihydroartemisinin-piperaquine (DHA-PPQ), the current first-line treatment, we carried out a study on the efficacy of this treatment. Between September 2012 and February 2013, we conducted a 42-day in vivo and in vitro efficacy study in Quang Nam Province. Treatment was directly observed, and blood samples were collected twice daily until parasite clearance. In addition, genotyping, quantitative PCR (qPCR), and in vitro sensitivity testing of isolates was performed. The primary endpoints were parasite clearance rate and time. The secondary endpoints included PCR-corrected and uncorrected cure rates, qPCR clearance profiles, in vitro sensitivity results (for chloroquine, dihydroartemisinin, and piperaquine), and genotyping for mutations in the Kelch 13 propeller domain. Out of 672 screened patients, 95 were recruited and 89 available for primary endpoint analyses. The median parasite clearance time (PCT) was 61.7 h (interquartile range [IQR], 47.6 to 83.2 h), and the median parasite clearance rate had a slope half-life of 6.2 h (IQR, 4.4 to 7.5 h). The PCR-corrected efficacy rates were estimated at 100% at day 28 and 97.7% (95% confidence interval, 91.2% to 99.4%) at day 42. At day 3, the P. falciparum prevalence by qPCR was 2.5 times higher than that by microscopy. The 50% inhibitory concentrations (IC50s) of isolates with delayed clearance times (≥ 72 h) were significantly higher than those with normal clearance times for all three drugs. Delayed parasite clearance (PCT, ≥ 72 h) was significantly higher among day 0 samples carrying the 543 mutant allele (47.8%) than those carrying the wild-type allele (1.8%; P = 0.048). In central Vietnam, the efficacy of DHA-PPQ is still satisfactory, but the parasite clearance time

  5. Stress analysis method for clearance-fit joints with bearing-bypass loads

    Science.gov (United States)

    Naik, R. A.; Crews, J. H., Jr.

    1989-01-01

    Within a multi-fastener joint, fastener holes may be subjected to the combined effects of bearing loads and loads that bypass the hole to be reacted elsewhere in the joint. The analysis of a joint subjected to search combined bearing and bypass loads is complicated by the usual clearance between the hole and the fastener. A simple analysis method for such clearance-fit joints subjected to bearing-bypass loading has been developed in the present study. It uses an inverse formulation with a linear elastic finite-element analysis. Conditions along the bolt-hole contact arc are specified by displacement constraint equations. The present method is simple to apply and can be implemented with most general purpose finite-element programs since it does not use complicated iterative-incremental procedures. The method was used to study the effects of bearing-bypass loading on bolt-hole contact angles and local stresses. In this study, a rigid, frictionless bolt was used with a plate having the properties of a quasi-isotropic graphite/epoxy laminate. Results showed that the contact angle as well as the peak stresses around the hole and their locations were strongly influenced by the ratio of bearing and bypass loads. For single contact, tension and compression bearing-bypass loading had opposite effects on the contact angle. For some compressive bearing-bypass loads, the hole tended to close on the fastener leading to dual contact. It was shown that dual contact reduces the stress concentration at the fastener and would, therefore, increase joint strength in compression. The results illustrate the general importance of accounting for bolt-hole clearance and contact to accurately compute local bolt-hole stresses for combined bearings and bypass loading.

  6. Antibody response following Hepatitis B vaccination in peritoneal dialysis patients: does normalized urea clearance matter?

    Directory of Open Access Journals (Sweden)

    Erkan Dervisoglu

    2011-01-01

    Full Text Available OBJECTIVES: Data on the factors that contribute to the antibody response to hepatitis B virus vaccination in peritoneal dialysis patients are scarce. The current study was conducted on a group of peritoneal dialysis patients to learn how the response to hepatitis B virus vaccination varies according to the patient's clearance of urea normalized to total body water (Kt/V. METHODS: A convenience sample of 33 peritoneal dialysis patients (13 women and 20 men, with a mean age of 49¡12 years was administered double doses (20 μg IM in each deltoid muscle of recombinant hepatitis B vaccine at 0, 1, 2, and 6 months. Response to immunization was measured at one to three months after the final dose of vaccine. The subjects were divided into groups according to the level of antibodies to hepatitis B surface antigen (anti-HBs, including non-responders ( 100 IU/L. RESULTS: Among non-responders, weak responders, and good responders, significant differences were found in age (54 ± 12 vs. 56 ± 9 vs. 45¡12 years, respectively; p = 0.049 and recombinant human erythropoietin use (20 vs. 29 vs. 76%, respectively; p = 0.016. No significant differences in weekly total Kt/V (p = 0.704, weekly peritoneal Kt/V (p = 0.064 and residual glomerular filtration rate (p = 0.355 were found across the three groups. CONCLUSIONS: Delivered clearance measured by weekly peritoneal Kt/V and total clearance measured by weekly total Kt/V did not predict the response to hepatitis B virus vaccination in patients on peritoneal dialysis.

  7. Impact of variable domain glycosylation on antibody clearance: an LC/MS characterization.

    Science.gov (United States)

    Huang, Lihua; Biolsi, Susan; Bales, Kelly R; Kuchibhotla, Uma

    2006-02-15

    Variable (Fv) domain N-glycosylation sites are found in approximately 20% of human immunoglobulin Gs (IgGs) in addition to the conserved N-glycosylation sites in the C(H)2 domains. The carbohydrate structures of the Fv glycans and their impact on in vivo half-life are not well characterized. Oligosaccharide structures in a humanized anti-Abeta IgG1 monoclonal antibody (Mab) with an N-glycosylation site in the complementary determining region (CDR2) of the heavy chain variable region were elucidated by LC/MS analysis following sequential exoglycosidase treatments of the endoproteinase Lys-C digest. Results showed that the major N-linked oligosaccharide structures in the Fv region have three characteristics (core-fucosylated biantennary oligosaccharides with one or two N-glycolylneuraminic acid [NeuGc] residues, zero or one alpha-linked Gal residue, and zero or one beta-linked GalNAc residue), whereas N-linked oligosaccharides in the Fc region contained typical Fc glycans (core-fucosylated, biantennary oligosaccharides with zero to two Gal residues). To elucidate the contribution of Fv glycans to the half-life of the antibody, a method that allows capture of the Mab and determination of its glycan structures at various time points after administration to mice was developed. Anti-Abeta antibody in mouse serum was immunocaptured by immobilized goat anti-human immunoglobulin Fc(gamma) antibody resin, and the captured material was treated with papain to generate Fab and Fc for LC/MS analysis. Different glycans in the Fc region showed the same clearance rate as demonstrated previously. In contrast to many other non-antibody glycosylated therapeutics, there is no strong correlation between oligosaccharide structures in the Fv region and their clearance rates in vivo. Our data indicated that biantennary oligosaccharides lacking galactosylation had slightly faster clearance rates than other structures in the Fv domain. PMID:16360109

  8. Is the new GFR equation using inulin clearance a more accurate method for Asian patients?

    Science.gov (United States)

    Kim, Beom Seok; Lee, Yong Kyu; Choi, Hoon Young; Choi, Seung Ok; Shin, Sug Kyun; Ha, Sung Kyu; Lee, Kang Wook; Kim, Yang Wook; Kim, Yong Lim; Yasuda, Yoshinari; Imai, Enyu; Horio, Masaru; Tomino, Yasuhiko; Matsuo, Seiichi; Lee, Ho Yung

    2015-12-01

    Recently, a new glomerular filtration rate (GFR) equation for the Japanese population was proposed using measured inulin clearance. To expand its applicability to other Asian populations, we performed a comparative study in the Korean population. Inulin clearance was measured in 166 patients from seven participating medical centers in Korea. Patient's sera and urine were collected, and baseline clinical characteristics were measured to provide an estimated GFR (eGFR) by the Japanese GFR equation using inulin clearance (Japanese-GFR equation), the Modification of Diet in Renal Disease (MDRD) study equation, and the Chronic Kidney Disease - Epidemiology Collaboration (CKD-EPI) equation. We compared the results to determine which equation best estimated the measured GFR (mGFR). Accuracy (95% CI) within 30% of mGFR by the Japanese-GFR equation, the CKD-EPI equation and the MDRD study equation were 66 (58 - 72), 51 (43 - 58), and 55 (47 - 62)%, respectively. Bias (mGFR minus eGFR) were 3.4 ± 22.4, -12.0 ± 22.1, and -9.7 ± 23.8 mL/min/1.73 m2, respectively. The accuracy of the Japanese-GFR equation was significantly better than MDRD study equation in subjects with mGFR < 60 mL/min/1.73 m2 and in total subjects. The bias of the Japanese-GFR equation was significantly smaller compared with other two equations in total subjects. The Japanese-GFR equation has a higher accuracy with less bias than the other equations in estimating GFR in Korean populations. Further studies are required to determine if the current Japanese-GFR equation could represent the standard eGFR for other Asian populations.

  9. Clearance of the mutant androgen receptor in motoneuronal models of spinal and bulbar muscular atrophy.

    Science.gov (United States)

    Rusmini, Paola; Crippa, Valeria; Giorgetti, Elisa; Boncoraglio, Alessandra; Cristofani, Riccardo; Carra, Serena; Poletti, Angelo

    2013-11-01

    Spinal and bulbar muscular atrophy (SBMA) is an X-linked motoneuron disease caused by an abnormal expansion of a tandem CAG repeat in exon 1 of the androgen receptor (AR) gene that results in an abnormally long polyglutamine tract (polyQ) in the AR protein. As a result, the mutant AR (ARpolyQ) misfolds, forming cytoplasmic and nuclear aggregates in the affected neurons. Neurotoxicity only appears to be associated with the formation of nuclear aggregates. Thus, improved ARpolyQ cytoplasmic clearance, which indirectly decreases ARpolyQ nuclear accumulation, has beneficial effects on affected motoneurons. In addition, increased ARpolyQ clearance contributes to maintenance of motoneuron proteostasis and viability, preventing the blockage of the proteasome and autophagy pathways that might play a role in the neuropathy in SBMA. The expression of heat shock protein B8 (HspB8), a member of the small heat shock protein family, is highly induced in surviving motoneurons of patients affected by motoneuron diseases, where it seems to participate in the stress response aimed at cell protection. We report here that HspB8 facilitates the autophagic removal of misfolded aggregating species of ARpolyQ. In addition, though HspB8 does not influence p62 and LC3 (two key autophagic molecules) expression, it does prevent p62 bodies formation, and restores the normal autophagic flux in these cells. Interestingly, trehalose, a well-known autophagy stimulator, induces HspB8 expression, suggesting that HspB8 might act as one of the molecular mediators of the proautophagic activity of trehalose. Collectively, these data support the hypothesis that treatments aimed at restoring a normal autophagic flux that result in the more efficient clearance of mutant ARpolyQ might produce beneficial effects in SBMA patients.

  10. Glandular Proteome Identifies Antiprotease Cystatin C as a Critical Modulator of Airway Hydration and Clearance.

    Science.gov (United States)

    Evans, T Idil Apak; Joo, Nam Soo; Keiser, Nicholas W; Yan, Ziying; Tyler, Scott R; Xie, Weiliang; Zhang, Yulong; Hsiao, Jordy J; Cho, Hyung-Ju; Wright, Michael E; Wine, Jeffrey J; Engelhardt, John F

    2016-04-01

    Defects in the cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel lead to viscous secretions from submucosal glands that cannot be properly hydrated and cleared by beating cilia in cystic fibrosis (CF) airways. The mechanisms by which CFTR, and the predominant epithelial sodium channel (ENaC), control the hydration and clearance of glandular secretions remain unclear. We used a proteomics approach to characterize the proteins contained in CF and non-CF submucosal gland fluid droplets and found that differentially regulated proteases (cathepsin S and H) and their antiprotease (cystatin C) influenced the equilibration of fluid on the airway surface and tracheal mucociliary clearance (MCC). Contrary to prevailing models of airway hydration and clearance, cystatin C, or raising the airway surface liquid (ASL) pH, inhibited cathepsin-dependent ENaC-mediated fluid absorption and raised the height of ASL, and yet decreased MCC velocity. Importantly, coupling of both CFTR and ENaC activities were required for effective MCC and for effective ASL height equilibration after volume challenge. Cystatin C-inhibitable cathepsins controlled initial phases of ENaC-mediated fluid absorption, whereas CFTR activity was required to prevent ASL dehydration. Interestingly, CF airway epithelia absorbed fluid more slowly owing to reduced cysteine protease activity in the ASL but became abnormally dehydrated with time. Our findings demonstrate that, after volume challenge, pH-dependent protease-mediated coupling of CFTR and ENaC activities are required for rapid fluid equilibration at the airway surface and for effective MCC. These findings provide new insights into how glandular fluid secretions may be equilibrated at the airway surface and how this process may be impaired in CF. PMID:26334941

  11. RENAL CLEARANCE AND URINARY EXCRETION OF KANAMYCIN IN DOMESTIC RUMINANT SPECIES

    Directory of Open Access Journals (Sweden)

    I. JAVED, Z. U. RAHMAN, F. H. KHAN, F. MUHAMMAD, Z. IQBAL AND B. ASLAM

    2006-01-01

    Full Text Available Species dependent geonetical differences in renal clearance and urinary excretion of kanamycin were investigated in adult female buffaloes, cows, sheep and goats. The drug was administered as a single intravenous dose (5 mg/kg b.wt. Blood and urine samples were collected at various time intervals after drug administration. The plasma and urine concentrations of the drug were determined using the microbiological assay. The mean (± SE values for endogenous creatinine clearance (an index of glomerular filtration rate were 0.77 ± 0.05, 0.49 ± 0.07, 0.81 ± 0.07 and 0.98 ± 0.13 ml/min.kg in buffaloes, cows, sheep and goats, respectively. Experiments regarding kidney handling of kanamycin in these ruminant species revealed respective values of renal clearance as 0.08 ± 0.01, 0.07 ± 0.01, 0.19 ± 0.02 and 0.23 ± 0.04 ml/min.kg. Besides glomerular filtration, kanamycin was reabsorbed from the renal tubules of all ruminant species and actively secreted into the renal tubules of buffaloes and goats. The cumulative percentages of intravenous dose of kanamycin excreted through urine during 12 hours in buffaloes, cows, sheep and goats were 4.31 ± 0.37, 2.53 ± 0.30, 11.0 ± 1.04 and 15.8 ± 2.22, respectively. This species variation in the percentage of urinary excretion in these domestic ruminants coincides with their respective glomerular filtration rates, being the highest in goats, lowest in cows and intermediate in sheep and buffaloes.

  12. Amylase-creatinine clearance ratio. A simple test to predict gentamicin nephrotoxicity.

    Science.gov (United States)

    Aderka, D; Tene, M; Graff, E; Levo, Y

    1988-05-01

    The initial target of aminoglycoside nephrotoxicity is the proximal tubule. Yet, no simple test is available to predict such toxicity. Taking advantage of the fact that amylase is filtered in the glomerulus and reabsorbed by the proximal tubules, we prospectively examined in 23 patients if changes in renal amylase creatinine clearance ratio (ACCR) can predict gentamicin nephrotoxicity. Eighteen of these patients had an initial creatinine clearance (rCcr) above 30 mL/min. Eleven of them (group A) had an ACCR above 3.5% (control 3% +/- 1.03%) and all exhibited an average reduction of 32.2% +/- 11.6% in rCcr following one week of gentamicin therapy. In contrast, only one of seven patients (group B) with an initial ACCR below 3.5% had a reduction, albeit transient, in rCcr. During gentamicin therapy, group A patients had a further increase in ACCR which was proportional to the reduction observed in rCcr (r = -.54). Our preliminary data suggest that ACCR may prove a simple and possibly a reliable predictor of kidney function deterioration during gentamicin therapy in patients with rCcr above 30 mL/min: patients with pretherapy ACCR above 3.5% may exhibit a deterioration in the creatinine clearance during the first week of therapy. For patients with pretherapy renal failure (rCcr less than 30 mL/min) the creatinine levels (but not the ACCR) seem to retain their significance in predicting and monitoring further renal function deterioration during aminoglycoside therapy.

  13. The amylase-to-creatinine clearance ratio--a non-specific response to acute illness?

    Science.gov (United States)

    McMahon, M J; Playforth, M J; Rashid, S A; Cooper, E H

    1982-01-01

    It was felt that the apparent specificity of the amylase-to-creatine clearance ratio (ACCR) in several previous studies of pancreatitis might reflect a failure to utilize adequately ill control subjects. The ACCR and the renal clearances of beta 2-microglobulin (B2-m), similarly related to creatinine (BCCR) as well as the urinary concentration of albumin, were compared in 27 patients with acute pancreatitis, 8 with a perforated peptic ulcer and 7 with mild biliary colic, during the first 5 days in hospital. Acute pancreatitis was graded as mild (6), moderate (14) or severe (7), using a combination of clinical data, diagnostic peritoneal lavage and multiple criteria. Further assessment of the severity of the acute illness was obtained from measurement of C-reactive protein (C-RP). Lowest C-RP levels were found in the patients with mild pancreatitis and biliary colic, and highest levels in the patients with severe pancreatitis and perforated ulcer (P less than 0.002). Similarly, ACCR and BCCR levels were significantly lower in the two mild groups than in the two severe ones (P less than 0.01 and less than 0.002 respectively), although plasma amylase was raised only in patients with pancreatitis and plasma B2-m was similar in all groups. Electrophoresis of urine showed dense bands of tubuloprotein in patients from both severe groups. Urine albumin was higher in severe pancreatitis than in perforated ulcer (P less than 0.1), perhaps indicating a more specific glomerular lesion in pancreatitis. Thus a rise in amylase clearance appeared to be related to the severity of the acute illness, and may be a component of a non-specific tubuloproteinuria. In this study patients with a perforated peptic ulcer had increases in ACCR similar to those seen in patients with severe pancreatitis, and we are therefore doubtful whether ACCR has any role in the clinical diagnosis of pancreatic disease.

  14. Effect of needle puncture and electro-acupuncture on mucociliary clearance in anesthetized quails

    Directory of Open Access Journals (Sweden)

    Wang Tianshan

    2006-02-01

    Full Text Available Abstract Background Acupuncture therapy for obstructive respiratory diseases has been effectively used in clinical practice and the acupuncture points or acupoints of Zhongfu and Tiantu are commonly-used acupoints to treat patients with the diseases. Since the impaired mucociliary clearance is among the most important features of airway inflammation in most obstructive respiratory diseases, the effect of needle puncture and electro-acupuncture at the specific acupoints on tracheal mucociliary clearance was investigated in anesthetized quails. Methods Mucociliary transport velocity on tracheal mucosa was measured through observing the optimal pathway, and fucose and protein contents in tracheal lavages were determined with biochemical methods. In the therapeutic group, needle puncture or electro-acupuncture stimulation to the acupoints was applied without or with constant current output in 2 mA and at frequency of 100 Hz for 60 minutes. In the sham group, electro-acupuncture stimulation to Liangmen was applied. Results Our present experiments demonstrated that the electro-acupuncture stimulation to Zhongfu and Tiantu significantly increased tracheal mucociliary transport velocity and decreased the content of protein in the tracheal lavage, compared with the control group. Moreover, either needle puncture or electro-acupuncture stimulation to Zhongfu and Tiantu significantly reverted the human neutrophil elastase-induced decrease in tracheal mucociliary transport velocity and human neutrophil elastase -induced increase in the contents of fucose and protein in the tracheal lavage, compared with the control group. Conclusion These results suggest that either needle puncture or electro-acupuncture stimulation to the effective acupoints significantly improves both airway mucociliary clearance and the airway surface liquid and that the improvements maybe ascribed to both the special function of the points and the substantial stimulation of electricity.

  15. Microhaemodynamics within the blade tip clearance of a centrifugal turbodynamic blood pump.

    Science.gov (United States)

    Antaki, J F; Diao, C-G; Shu, F-J; Wu, J-C; Zhao, R; Kameneva, M V

    2008-05-01

    A persistent challenge facing the quantitative design of turbodynamic blood pumps is the great disparity of spatial scales between the primary and auxiliary flow paths. Fluid passages within journals and adjacent to the blade tips are often on the scale of several blood cells, confounding the application of macroscopic continuum models. Yet, precisely in these regions there exists the highest shear stress, which is most likely to cause cellular trauma. This disparity has motivated these microscopic studies to visualize the kinematics of the blood cells within the small clearances of a miniature turbodynamic blood pump. A transparent model of a miniature centrifugal pump having an adjustable tip clearance (50-200 microm) was prepared for direct optical visualization of the region between the impeller blade tip and the stationary housing. Synchronized images of the blood cells were obtained by a microscopic visualization system, consisting of an inverted microscope fitted with long-working-distance objective lens (40x), mercury lamp, and high-resolution charge-coupled device camera electronically triggered by the rotation of the impeller. Experiments with 7 microm fluorescent particles revealed the influence of the gap dimension on the trajectory across the blade thickness. The lateral component of velocity (perpendicular to the blade) was dramatically enhanced in the 50 microm gap compared with the 200 microm gap, thereby reducing the exposure time. Studies with diluted bovine blood (Ht = 0.5 per cent) showed that the concentration of cells traversing the gap is also reduced dramatically (30 per cent) as the blade tip clearance is reduced from 200 microm to 50 microm. These results motivate further investigation into the microfluidic phenomena responsible for cellular trauma within turbodynamic blood pumps. PMID:18595366

  16. Amylase-creatinine clearance ratio. A simple test to predict gentamicin nephrotoxicity.

    Science.gov (United States)

    Aderka, D; Tene, M; Graff, E; Levo, Y

    1988-05-01

    The initial target of aminoglycoside nephrotoxicity is the proximal tubule. Yet, no simple test is available to predict such toxicity. Taking advantage of the fact that amylase is filtered in the glomerulus and reabsorbed by the proximal tubules, we prospectively examined in 23 patients if changes in renal amylase creatinine clearance ratio (ACCR) can predict gentamicin nephrotoxicity. Eighteen of these patients had an initial creatinine clearance (rCcr) above 30 mL/min. Eleven of them (group A) had an ACCR above 3.5% (control 3% +/- 1.03%) and all exhibited an average reduction of 32.2% +/- 11.6% in rCcr following one week of gentamicin therapy. In contrast, only one of seven patients (group B) with an initial ACCR below 3.5% had a reduction, albeit transient, in rCcr. During gentamicin therapy, group A patients had a further increase in ACCR which was proportional to the reduction observed in rCcr (r = -.54). Our preliminary data suggest that ACCR may prove a simple and possibly a reliable predictor of kidney function deterioration during gentamicin therapy in patients with rCcr above 30 mL/min: patients with pretherapy ACCR above 3.5% may exhibit a deterioration in the creatinine clearance during the first week of therapy. For patients with pretherapy renal failure (rCcr less than 30 mL/min) the creatinine levels (but not the ACCR) seem to retain their significance in predicting and monitoring further renal function deterioration during aminoglycoside therapy. PMID:2452611

  17. The amylase-to-creatinine clearance ratio--a non-specific response to acute illness?

    Science.gov (United States)

    McMahon, M J; Playforth, M J; Rashid, S A; Cooper, E H

    1982-01-01

    It was felt that the apparent specificity of the amylase-to-creatine clearance ratio (ACCR) in several previous studies of pancreatitis might reflect a failure to utilize adequately ill control subjects. The ACCR and the renal clearances of beta 2-microglobulin (B2-m), similarly related to creatinine (BCCR) as well as the urinary concentration of albumin, were compared in 27 patients with acute pancreatitis, 8 with a perforated peptic ulcer and 7 with mild biliary colic, during the first 5 days in hospital. Acute pancreatitis was graded as mild (6), moderate (14) or severe (7), using a combination of clinical data, diagnostic peritoneal lavage and multiple criteria. Further assessment of the severity of the acute illness was obtained from measurement of C-reactive protein (C-RP). Lowest C-RP levels were found in the patients with mild pancreatitis and biliary colic, and highest levels in the patients with severe pancreatitis and perforated ulcer (P less than 0.002). Similarly, ACCR and BCCR levels were significantly lower in the two mild groups than in the two severe ones (P less than 0.01 and less than 0.002 respectively), although plasma amylase was raised only in patients with pancreatitis and plasma B2-m was similar in all groups. Electrophoresis of urine showed dense bands of tubuloprotein in patients from both severe groups. Urine albumin was higher in severe pancreatitis than in perforated ulcer (P less than 0.1), perhaps indicating a more specific glomerular lesion in pancreatitis. Thus a rise in amylase clearance appeared to be related to the severity of the acute illness, and may be a component of a non-specific tubuloproteinuria. In this study patients with a perforated peptic ulcer had increases in ACCR similar to those seen in patients with severe pancreatitis, and we are therefore doubtful whether ACCR has any role in the clinical diagnosis of pancreatic disease. PMID:6172175

  18. Determination of pulmonary deposition, translocation and clearance using neutron activation techniques

    International Nuclear Information System (INIS)

    Neutron activation provides a sensitive technique to estimate pulmonary deposition, translocation and clearance of inhaled particles. Talc and fly ash were irradiated in an integrated neutron flux of approximately 1016 n/cm2. Radionuclides were induced by (n, γ) reactions on major and minor elements in the dusts. Hamsters received a single nose-only exposure to the dusts. Groups of 4 to 6 animals were then serially sacrificed at intervals up to 4 months postexposure. Lungs, other tissues of interest and excreta were collected for γ-ray analysis. Limit of detection for the isotopes 60Co or 46Sc was approximately 0.1 dpm, facilitating detection of 10-11 quantities of these elements. Analyzing for more than one radionuclide and comparing their ratios in the bulk dust to those in the tissues or excreta indicated whether a radionuclide leached from the dust particle or represented particles in the tissue samples. Six to 8% of the inhaled talc were deposited in the alveoli; its biological half-life in the lung was 7 to 10 days. Alveolar clearance was essentially complete 4 months postexposure. No translocation of talc to liver, kidneys, ovaries of other parts of the body was found. Picogram quantities of 60Co found in the urine probably respresented leached 60Co, absorbed in the gastrointestinal tract. Two to 3% of the inhaled fly ash were initially retained in the respiratory tract. Estimated biological half-lives were 3 and 35 days for airways and alveoli, resp. After 99 days the mean lung burden had decreased to about 10% of its initial value; extrapolation suggests near-complete pulmonary clearance at about 200 days postexposure. (author)

  19. Minimum toe clearance adaptations to floor surface irregularity and gait speed.

    Science.gov (United States)

    Schulz, Brian W

    2011-04-29

    Toe speed during gait generally nears its maximum while its height reaches a local minima approximately halfway through swing phase. Trips are thought to frequently occur at these local minima (minimum toe clearance or MTC events) and trip risk has been quantified using the minimum distance between the toe and ground here (MTC). This study investigated MTC on floor surfaces with and without multiple small obstacles. After shoes and floor surfaces were digitized, 14 unimpaired subjects (half women) each traversed a 4.88 m walkway 4 times at slow, preferred, and fast speeds across surfaces with no obstacles, visible obstacles, and hidden obstacles. Both surfaces with obstacles had the same random obstacle configuration. Shoe and body segment motions were tracked using passive markers and MTC and joint kinematics calculated. All MTC and kinematic variables tested significantly increased with faster instructed gait speed except the likelihood of MTC event occurrence (local minima in minimum toe clearance trajectory when foot is in upper quartile of speed). MTC events were less frequent for swing phases on surfaces with obstacles (80% vs. 98% for no obstacles). MTC values, when present, were doubled by the presence of visible obstacles (22.2 ± 7.3mm vs. 11.1 ± 5.7 mm) and further increased to 26.8 ± 7.1mm when these obstacles were hidden from view (all comparisons p ≤ 0.0003). These substantial floor surface-related changes in MTC event occurrences and values resulted from alterations in toe- and heel-clearance trajectories caused by subtle but significant changes in joint kinematics that did not exceed 10% each joint's swing phase range of motion.

  20. Clearance of depot vaccine SPIO-labeled antigen and substrate visualized using MRI.

    Science.gov (United States)

    Brewer, Kimberly D; Lake, Kerry; Pelot, Nicole; Stanford, Marianne M; DeBay, Drew R; Penwell, Andrea; Weir, Genevieve M; Karkada, Mohan; Mansour, Marc; Bowen, Chris V

    2014-12-01

    Immunotherapies, including peptide-based vaccines, are a growing area of cancer research, and understanding their mechanism of action is crucial for their continued development and clinical application. Exploring the biodistribution of vaccine components may be key to understanding this action. This work used magnetic resonance imaging (MRI) to characterize the in vivo biodistribution of the antigen and oil substrate of the vaccine delivery system known as DepoVax(TM). DepoVax uses a novel adjuvanted lipid-in-oil based formulation to solubilise antigens and promote a depot effect. In this study, antigen or oil were tagged with superparamagnetic iron oxide (SPIO), making them visible on MR images. This enables tracking of individual vaccine components to determine changes in biodistribution. Mice were injected with SPIO-labeled antigen or SPIO-labeled oil, and imaged to examine clearance of labeled components from the vaccine site. The SPIO-antigen was steadily cleared, with nearly half cleared within two months post-vaccination. In contrast, the SPIO-oil remained relatively unchanged. The biodistribution of the SPIO-antigen component within the vaccine site was heterogeneous, indicating the presence of active clearance mechanisms, rather than passive diffusion or drainage. Mice injected with SPIO-antigen also showed MRI contrast for several weeks post-vaccination in the draining inguinal lymph node. These results indicate that MRI can visualize the in vivo longitudinal biodistribution of vaccine components. The sustained clearance is consistent with antigen up-take and trafficking by immune cells, leading to accumulation in the draining lymph node, which corresponds to the sustained immune responses and reduced tumor burden observed in vaccinated mice. PMID:25444822

  1. EMS Adherence to a Pre-hospital Cervical Spine Clearance Protocol

    Directory of Open Access Journals (Sweden)

    Johnson, David

    2001-10-01

    Full Text Available Purpose: To determine the degree of adherence to a cervical spine (c-spine clearance protocol by pre-hospital Emergency Medical Services (EMS personnel by both self-assessment and receiving hospital assessment, to describe deviations from the protocol, and to determine if the rate of compliance by paramedic self-assessment differed from receiving hospital assessment. Methods: A retrospective sample of pre-hospital (consecutive series and receiving hospital (convenience sample assessments of the compliance with and appropriateness of c-spine immobilization. The c-spine clearance protocol was implemented for Orange County EMS just prior to the April-November 1999 data collection period. Results: We collected 396 pre-hospital and 162 receiving hospital data forms. From the pre-hospital data sheet. the percentage deviation from the protocol was 4.096 (16/396. Only one out of 16 cases that did not comply with the protocol was due to over immobilization (0.2%. The remaining 15 cases were under immobilized, according to protocol. Nine of the under immobilized cases (66% that should have been placed in c-spine precautions met physical assessment criteria in the protocol, while the other five cases met mechanism of injury criteria. The rate of deviations from protocol did not differ over time. The receiving hospital identified 8.0% (13/162; 6/16 over immobilized, 7/16 under immobilized of patients with deviations from the protocol; none was determined to have actual c-spine injury. Conclusion: The implementation of a pre-hospital c-spine clearance protocol in Orange County was associated with a moderate overall adherence rate (96% from the pre-hospital perspective, and 92% from the hospital perspective, p=.08 for the two evaluation methods. Most patients who deviated from protocol were under immobilized, but no c-spine injuries were missed. The rate of over immobilization was better than previously reported, implying a saving of resources.

  2. Abnormal norepinephrine clearance and adrenergic receptor sensitivity in idiopathic orthostatic intolerance

    Science.gov (United States)

    Jacob, G.; Shannon, J. R.; Costa, F.; Furlan, R.; Biaggioni, I.; Mosqueda-Garcia, R.; Robertson, R. M.; Robertson, D.

    1999-01-01

    BACKGROUND: Chronic orthostatic intolerance (OI) is characterized by symptoms of inadequate cerebral perfusion with standing, in the absence of significant orthostatic hypotension. A heart rate increase of >/=30 bpm is typical. Possible underlying pathophysiologies include hypovolemia, partial dysautonomia, or a primary hyperadrenergic state. We tested the hypothesis that patients with OI have functional abnormalities in autonomic neurons regulating cardiovascular responses. METHODS AND RESULTS: Thirteen patients with chronic OI and 10 control subjects underwent a battery of autonomic tests. Systemic norepinephrine (NE) kinetics were determined with the patients supine and standing before and after tyramine administration. In addition, baroreflex sensitivity, hemodynamic responses to bolus injections of adrenergic agonists, and intrinsic heart rate were determined. Resting supine NE spillover and clearance were similar in both groups. With standing, patients had a greater decrease in NE clearance than control subjects (55+/-5% versus 30+/-7%, P<0.02). After tyramine, NE spillover did not change significantly in patients but increased 50+/-10% in control subjects (P<0.001). The dose of isoproterenol required to increase heart rate 25 bpm was lower in patients than in control subjects (0.5+/-0.05 versus 1.0+/-0.1 microg, P<0.005), and the dose of phenylephrine required to increase systolic blood pressure 25 mm Hg was lower in patients than control subjects (105+/-11 versus 210+/-12 microg, P<0.001). Baroreflex sensitivity was lower in patients (12+/-1 versus 18+/-2 ms/mm Hg, P<0.02), but the intrinsic heart rate was similar in both groups. CONCLUSIONS: The decreased NE clearance with standing, resistance to the NE-releasing effect of tyramine, and increased sensitivity to adrenergic agonists demonstrate dramatically disordered sympathetic cardiovascular regulation in patients with chronic OI.

  3. Mapping soil magnetic properties in Bosnia and Herzegovina for landmine clearance operations

    Science.gov (United States)

    Hannam, J. A.; Dearing, J. A.

    2008-10-01

    Electromagnetic properties of soils have negative impacts on metal detector performance during landmine clearance operations. In particular, topsoils with high concentrations of pedogenic viscous superparamagnetic minerals (magnetite/maghemite) as shown by high values of magnetic susceptibility and frequency dependent susceptibility limit the detector capability of identifying buried landmines. Thus a priori knowledge of the spatial extent of soils that may be problematic for landmine detection would aid strategic planning of clearance operations and ensure appropriate equipment is deployed. Here, we compare two approaches for estimating the broad magnetic properties of soils in Bosnia and Herzegovina: 1) an analogue approach, using data for magnetic susceptibility and frequency dependent susceptibility available for soil types from other temperate and Mediterranean regions; 2) magnetic measurements of a stratified sample of soil samples taken from the Bosnian National Soil Archive. The national soil magnetic maps produced estimate that the area of land inferred as problematic for metal detectors is 4% and 30% according to the analogue and measurement methods respectively. Combining soil type with soil parent material and climate explains the spatial variability of soil magnetic properties in terms of mechanisms of secondary ferrimagnetic mineral production and accumulation. The resulting maps indicate that the magnetic properties of dominant soils in northern Bosnia tend to be unproblematic for detectors, while in central Bosnia there is likely to be moderate detector interference. However, there is a high likelihood of dominant soils affecting detectors in southern and western Bosnia and Herzegovina, equivalent to ~ 30% of the total land area. The mapped outputs of susceptibility and frequency dependent susceptibility provide demining end-users with an indication of the likelihood of encountering problem soils in areas selected for clearance operations.

  4. The role of blood lactate clearance as a predictor of mortality in children undergoing surgery for tetralogy of Fallot

    Directory of Open Access Journals (Sweden)

    Suruchi Ladha

    2016-01-01

    Full Text Available Background: The identification of biomarkers for predicting morbidity and mortality, particularly in pediatric population undergoing cardiac surgery will contribute toward improving the patient outcome. There is an increasing body of literature establishing the clinical utility of hyperlactatemia and lactate clearance as prognostic indicator in adult cardiac surgical patients. However, the relationship between lactate clearance and mortality risk in the pediatric population remains to be established. Objective: To assess the role of lactate clearance in determining the outcome in children undergoing corrective surgery for tetralogy of Fallot (TOF. Methods and Study Design: A prospective, observational study. Setting: A tertiary care center. Study Population: Two hundred children undergoing elective surgery for TOF. Study Method: Blood lactate levels were obtained as baseline before operation (T0, postoperatively at admission to the cardiac intensive care unit after surgery (T1, and then at every 6 h for the first 24 h of Intensive Care Unit (ICU stay (T6, T12, T18, and T24, respectively. The lactate clearance in the study is defined by the equation ([lactate initial - lactate delayed]/lactate initial ×100%. Lactate clearance was determined at T1-T6, T1-T12, T1-T18, and T1-T24 time interval, respectively. The primary outcome measured was mortality. Secondary outcomes measured were the duration of mechanical ventilation, duration of inotropic requirement, and duration of ICU stay. Results: Eleven out of the two hundred patients enrolled in the study died. Nonsurvivors had higher postoperative lactate concentration (P 10%, relative to patients with a lactate clearance 10% after 6 h have improved outcome compared with those with lower lactate clearance.

  5. Interferon lambda 4 (IFNL4) gene polymorphism is associated with spontaneous clearance of HCV in HIV-1 positive patients

    Science.gov (United States)

    Alves, Camila Fernanda da Silveira; Grott, Camila Schultz; Lunge, Vagner Ricardo; Béria, Jorge Umberto; Tietzmann, Daniela Cardoso; Stein, Airton Tetelbom; Simon, Daniel

    2016-01-01

    Abstract Approximately one-third of the individuals infected with human immunodeficiency virus type 1 (HIV-1) are co-infected with hepatitis C virus (HCV). Co-infected patients have an increased risk for developing end-stage liver diseases. Variants upstream of the IFNL3 gene have been associated with spontaneous and treatment-induced clearance of HCV infection. Recently, a novel polymorphism was discovered, denoted IFNL4 ΔG > TT (rs368234815), which seems to be a better predictor of spontaneous clearance than the IFNL4 rs12979860 polymorphism. We aimed to determine the prevalence of the IFNL4 ΔG > TT variants and to evaluate the association with spontaneous clearance of HCV infection in Brazilian HIV-1 patients. The IFNL4 ΔG > TT genotypes were analyzed by polymerase chain reaction followed by restriction digestion in 138 HIV-1 positive patients who had an anti-HCV positive result. Spontaneous clearance of HCV was observed in 34 individuals (24.6%). IFNL4 genotype distribution was significantly different between individuals who had spontaneous clearance and chronic HCV patients (p=0.002). The probability of spontaneous clearance of HCV infection for patients with the IFNL4 TT/TT genotype was 3.6 times higher than for patients carrying the IFNL4 ΔG allele (OR=3.63, 95% CI:1.51-8.89, p=0.001). The IFNL4 ΔG > TT polymorphism seems to be better than IFNL4 rs12979860 to predict spontaneous clearance of the HCV in Brazilian HIV-1 positive patients. PMID:27560987

  6. Factors influencing the clearance rates of colloidal particles from the rabbit knee joint

    International Nuclear Information System (INIS)

    Three aspects of colloidal drug delivery are examined. (a) Interaction of liposomes, containing the anti-inflammatory agent chloroquine with sinovial fluid. Changes in the surface charge of particles in the presence of sinovial fluid, and changes in viscosity are examined. (b) Influence of liposome concentration, drug concentration and surface change on the rate of macrophage uptake. (c) Use of gamma scintigraphy to determine clearance kinetics of various types of particles, influence of particle size, charge and chemical composition on uptake. (U.K.)

  7. Slow recovery from disturbance: a 20 year study of Ascophyllum canopy clearances

    OpenAIRE

    A. Ingólfsson; Hawkins, S.J.

    2008-01-01

    We describe an experiment where Ascophyllym nodosum was removed from two 1 x 1 m plots in south-western Iceland in August 1985. The plots were studied regularly until 2005. Recovery of the Ascophyllum canopy took 7–8 years. The understorey algae in one of the plots consisted mostly of extensive growth of Cladophora rupestris, which died within a year of Ascophyllum clearance. No Cladophora had reappeared by 2005, although it was healthy and abundant in control plots throughout the study perio...

  8. Regulatory issues associated with exclusion, exemption, and clearance related to the mining and minerals processing industries

    International Nuclear Information System (INIS)

    The concepts of exclusion, exemption and clearance have been established in international recommendations and, standards for radiation protection and the management of radioactive waste in recent years. The consistent application of these concepts has given rise to various problems in different spheres of use. This is particularly the case in the mining and minerals processing industries dealing with materials exhibiting elevated concentrations of naturally occurring radionuclides. This paper takes the South African mining industry as an example and highlights some of the issues that have arisen in applying these concepts within a regulatory control regime. (author)

  9. RESEARCH IN STABILITY OF PERIODIC MOTION, BIFURCATION AND CHAOS IN A VIBRATORY SYSTEM WITH A CLEARANCE

    Institute of Scientific and Technical Information of China (English)

    LuoGuanwei; XieJianhua

    2003-01-01

    A two-degrees-of-freedom vibratory system with a clearance or gap is under consideration based on the Poincard map. Stability and local bifurcation of the period-one doubleimpact symmetrical motion of the system are analyzed by using the equation of map. The routes from periodic impact motions to chaos, via pitchfork bifurcation, period-doubling bifurcation and grazing bifurcation, are studied by numerical simulation. Under suitable system parameter conditions, Neimark-Sacker bifurcations associated with periodic impact motion can occur in the two-degrees-of-freedom vibro-impact system.

  10. /sup 131/I-Orthoiodohippurate clearance in the detection of cisplatin nephrotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    Hengst, W.; Wieler, H.; Rabs, U.; Buerger, R.A.

    1985-06-01

    In this study, 26 patients were treated with 20 mg cisplatin (CP)/m/sup 2/ body surface daily for 5 days as part of a combination therapy for testicular cancer. Simultaneously a vigorous hyperhydration (3000 ml daily) was applied to reduce the nephrotoxic effect induced by the drug. sup(/sup 131/I)-orthoiodophippurate clearance values obtained by the modified method of Oberhausen did not show any significant evidence of tubular dysfunction after therapy. These results may have been due to the vigorous hydration as well as to the youth of the patients.

  11. 131I-orthoiodohippurate clearance in the detection of cisplatin nephrotoxicity

    International Nuclear Information System (INIS)

    In this study, 26 patients were treated with 20 mg cisplatin (CP)/m2 body surface daily for 5 days as part of a combination therapy for testicular cancer. Simultaneously a vigorous hyperhydration (3000 ml daily) was applied to reduce the nephrotoxic effect induced by the drug. sup(131I)-orthoiodophippurate clearance values obtained by the modified method of Oberhausen did not show any significant evidence of tubular dysfunction after therapy. These results may have been due to the vigorous hydration as well as to the youth of the patients. (orig.)

  12. Antibody response following Hepatitis B vaccination in peritoneal dialysis patients: does normalized urea clearance matter?

    OpenAIRE

    Erkan Dervisoglu; Melih Simsek; Ahmet Yilmaz

    2011-01-01

    OBJECTIVES: Data on the factors that contribute to the antibody response to hepatitis B virus vaccination in peritoneal dialysis patients are scarce. The current study was conducted on a group of peritoneal dialysis patients to learn how the response to hepatitis B virus vaccination varies according to the patient's clearance of urea normalized to total body water (Kt/V). METHODS: A convenience sample of 33 peritoneal dialysis patients (13 women and 20 men, with a mean age of 49¡12 years) was...

  13. In situ method for measurements of community clearance rate on shallow water bivalve populations

    DEFF Research Database (Denmark)

    Hansen, Benni W.; Dolmer, Per; Vismann, Bent

    2011-01-01

    An open-top chamber was designed for measuring ambient community clearance rate on undisturbed bivalve populations in the field. The chamber was pressed 5-10 cm down in the sediment on the mussel bed. It holds approximately 30-40 cm water column equal to a volume of 43-77 L. It was provided...... with an air lift connected to a SCUBA diver pressure tank generating a continuous and gentle water circulation. This ensures a complete mixture of suspended particles, and thereby, a maximum filtration by the bivalves. An in situ fluorometer was mounted to record plant pigment reduction due to mussel...

  14. IL-10 neutralization promotes parasite clearance in splenic aspirate cells from patients with visceral leishmaniasis.

    Science.gov (United States)

    Gautam, Shalini; Kumar, Rajiv; Maurya, Radheshyam; Nylén, Susanne; Ansari, Nasim; Rai, Madhukar; Sundar, Shyam; Sacks, David

    2011-10-01

    The mechanisms underlying the failure to contain the growth of Leishmania parasites in human visceral leishmaniasis (VL) are not understood. L donovani amastigotes were quantified in cultured splenic aspirate cells to assess the function of IL-10 in lesional tissue ex vivo. In 67 patients with active VL, IL-10 neutralization promoted parasite killing in 73% and complete clearance in 30%, while 18% had more parasites and 9% did not change. The splenic cells secreted increased levels of both tumor necrosis factor α (TNFα) and interferon γ (IFNγ) under IL-10-neutralizing conditions. These findings provide direct support for targeting IL-10 as an approach to therapy in human VL. PMID:21881130

  15. A Pathological Fracture of the Mandible due to Osteomyelitis following a Full Dental Clearance.

    Science.gov (United States)

    Jauhar, Preeti; Handley, Thomas; Hammersley, Nicholas

    2016-03-01

    Orofacial infections following dental extractions are a common referral to an oral and maxillofacial department as an emergency, especially when combined with swelling and limited mouth opening. The case presented demonstrates a rare complication of chronic suppurative osteomyelitis with bilateral pathological fractures of the mandible, which occurred following a staged dental clearance. CPD/Clinical Relevance: Dental extractions are one of the most common treatments carried out by oral surgeons and general dental practitioners. This case highlights a rare but encountered complication of routine oral surgery and demonstrates when it is necessary to make an immediate referral to the local oral and maxillofacial surgery unit. PMID:27188132

  16. The microbiota mediates pathogen clearance from the gut lumen after non-typhoidal Salmonella diarrhea.

    Directory of Open Access Journals (Sweden)

    Kathrin Endt

    Full Text Available Many enteropathogenic bacteria target the mammalian gut. The mechanisms protecting the host from infection are poorly understood. We have studied the protective functions of secretory antibodies (sIgA and the microbiota, using a mouse model for S. typhimurium diarrhea. This pathogen is a common cause of diarrhea in humans world-wide. S. typhimurium (S. tm(att, sseD causes a self-limiting gut infection in streptomycin-treated mice. After 40 days, all animals had overcome the disease, developed a sIgA response, and most had cleared the pathogen from the gut lumen. sIgA limited pathogen access to the mucosal surface and protected from gut inflammation in challenge infections. This protection was O-antigen specific, as demonstrated with pathogens lacking the S. typhimurium O-antigen (wbaP, S. enteritidis and sIgA-deficient mice (TCRβ(-/-δ(-/-, J(H (-/-, IgA(-/-, pIgR(-/-. Surprisingly, sIgA-deficiency did not affect the kinetics of pathogen clearance from the gut lumen. Instead, this was mediated by the microbiota. This was confirmed using 'L-mice' which harbor a low complexity gut flora, lack colonization resistance and develop a normal sIgA response, but fail to clear S. tm(att from the gut lumen. In these mice, pathogen clearance was achieved by transferring a normal complex microbiota. Thus, besides colonization resistance ( = pathogen blockage by an intact microbiota, the microbiota mediates a second, novel protective function, i.e. pathogen clearance. Here, the normal microbiota re-grows from a state of depletion and disturbed composition and gradually clears even very high pathogen loads from the gut lumen, a site inaccessible to most "classical" immune effector mechanisms. In conclusion, sIgA and microbiota serve complementary protective functions. The microbiota confers colonization resistance and mediates pathogen clearance in primary infections, while sIgA protects from disease if the host re-encounters the same pathogen. This has

  17. Amylase/creatinine clearance ratio and tubular proteinuria in acute pancreatitis.

    Science.gov (United States)

    Lankisch, P G; Wolfrum, D I; Koop, H; Winckler, K

    1979-01-01

    Amylase/creatinine clearance ratio (CAm/CCr), urinary protein concentration and urinary protein pattern were studied in 102 samples from 27 patients with acute pancreatitis and in 46 controls. Raised CAm/CCr, proteinuria and a tubular protein pattern were present in 74, 56 and 96% of the patients, respectively. However, CAm/CCr and proteinuria and CAm/CCr and tubular protein pattern were not correlated. These results do not support the suggestion that an elevated CAm/CCr in acute pancreatitis is due to generalized tubular protein reabsorption failure presenting with tubular proteinuria.

  18. Amylase: creatinine clearance ratio and urinary excretion of lysozyme in acute pancreatitis and acute duodenal perforation.

    Science.gov (United States)

    Berger, G M; Cowlin, J; Turner, T J

    1976-09-18

    The amylase:creatinine clearance ratio in patients suffering from acute pancreatitis or acute duodenal perforation was higher than normal in both groups of patients. These findings cast doubt on the value of this parameter as a specific index of acute pancreatitis. The mechanism or mechanisms underlying the increased amylase excretion have not been determined. However, the markedly elevated urinary excretion of lysozyme observed in some patients suggests, by analogy, that diminished tubular reabsorption of amylase may contribute towards the elevated amylase:creatinine ratio.

  19. Tip clearance flow interaction with circumferential groove casing treatment in a transonic axial compressor

    Science.gov (United States)

    Ross, Mark Hamilton

    Experimental and computational studies were conducted to study the role of the tip leakage flow in axial compressor stall and the relationship between the tip clearance flow flow field and surge margin extension from circumferential groove casing treatment. The CFD results were used to identify the existence of an interface between the approach ow and the tip-leakage flow. The experiments used a surface streaking visualization method to identify the time-averaged location of this interface as a line of zero axial shear stress at the casing. The axial position of this line, denoted xzs, moved upstream with decreasing ow coefficient in both the experiments and computations. The line was consistently located at the rotor leading edge plane at the stalling flow coefficient, regardless of in flow boundary condition. These results were successfully modeled using a control volume approach that balanced the reverse axial momentum ux of the tip-leakage flow with the momentum flux of the approach fluid. Non-uniform tip clearance measurements demonstrated that movement of the interface upstream of the rotor leading edge plane leads to the generation of short length scale rotating disturbances. Therefore, stall was interpreted as a critical point in the momentum flux balance of the approach ow and the reverse axial momentum flux of the tip-leakage flow. Experimental measurements of surge margin extension from seven CGCT configurations with a fixed groove geometry demonstrated that the contribution of individual grooves in a multi-groove casing to surge margin extension is an (a) additive and (b) linear function of the smooth wall tip clearance axial momentum ux at the location of a each groove. Extending the axial momentum model to include the in uence of a CGCT showed that circumferential grooves reduce the tip leakage flow axial momentum through radial transport. The equivalent force due to a circumferential groove was demonstrated to be related to the smooth wall tip

  20. Pregnancy does not alter the metabolic clearance of 1,25-dihydroxyvitamin D in rats

    International Nuclear Information System (INIS)

    Increased circulating levels of 1,25-dihydroxyvitamin D [1,25(OH)2D] during pregnancy could be due to an increase in production or decrease in the metabolic clearance rate of 1,25(OH)2D. To answer this question an isotope dilution method was used to determine the clearance rate of 1,25(OH)2D in pregnant and aged-matched nonpregnant female rats. A bolus of 0.146 muCi 1,25(OH)2[3H]D3 was given to 60 pregnant and 60 aged-matched nonpregnant rats and the disappearance of the isotope was followed in these animals over the next 48 h. In 12 pregnant rats vs. 14 nonpregnant controls not injected with tracer, plasma calcium (9.6 +/- 0.41 vs. 10.7 +/- 0.17 mg/ml) and 25(OH)D (17.1 +/- 1.15 vs. 25.4 +/- 1.58 ng/ml) levels were significantly lower (P less than 0.01 and P less than 0.001), whereas plasma 1,25(OH)2D levels (110 +/- 16.1 pg/ml vs. 77 +/- 6.0 pg/ml) were significantly higher (P less than 0.05). Clearance rates of 1,25(OH)2D of 25.8 +/- 1.31 microliters/min in pregnant rats and 20.2 20.2 +/- 1.38 microliters/min in nonpregnant aged-matched rats were not significantly different. Similarly, the apparent volume of distribution of 1,25(OH)2D in the pregnant rats (15 +/- 1.0 ml) was not significantly different from that in the nonpregnant control animals (18 +/- 2.1 ml). Production rates of.1,25(OH)2D were elevated in the pregnant rats (2.83 pg/min) compared with the nonpregnant controls (1.55 pg/min). In conclusion, the elevated maternal plasma 1,25(OH)2D level during pregnancy is a result of increased production and is not due to a decreased clearance