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Liver stiffness assessed by shear-wave elastography declines in parallel with immunoregulatory proteins in patients with chronic HCV infection during DAA therapy. Clin Hemorheol Microcirc 2021; 79:541-555. [PMID: 34120896 DOI: 10.3233/ch-211193] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
BACKGROUND A rapid decline of liver stiffness (LS) was detected by non-invasive methods in patients with chronic hepatitis C (HCV) infection during treatment with direct-acting antivirals (DAA). OBJECTIVE To investigate the influence of inflammation on LS. METHODS We prospectively examined LS by sonographic shear-wave elastography in 217 patients during DAA therapy from treatment initiation (BL) to 12 weeks after end of therapy (SVR12). Demographic data, laboratory findings and serum levels of cytokines were determined. RESULTS Values of LS decreased from 1.86 m/s to 1.68 m/s (p = 0.01) which was most pronounced in patients who had F4 fibrosis at BL (3.27 m/s to 2.37 m/s; p < 0.001). Initially elevated values of aminotransferases, ferritin, IgG (p < 0.001 each) and international normalized ratio (p < 0.003) declined, thrombocyte count (p = 0.007) increased. Correlations of these laboratory parameters with BL levels of LS measurement (LSM) were most apparent in patients with F1-F3 fibrosis. Tumor necrosis factor (TNF)-α (p = 0.031), interleukin (IL)-10 (p = 0.005) and interferon y inducible protein (IP)-10 (p < 0.001) decreased in parallel with LSM under DAA therapy and corelated with BL values. CONCLUSION Decrease of systemic inflammatory parameters correlated with LSM under DAA therapy. We conclude that regression of LSM is attributable to the decline of inflammation rather than reflecting fibrosis.
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Abstract
Organ donation has reached a new low in Germany. The number of organ donations dropped from 1296 in 2010 to just 797 organ donations in 2017. This represents a decrease of 916 kidney transplants in the last six years. Thus, Germany occupies the penultimate position in the Eurotransplant association with the number of organ donors per million inhabitants. Only Luxembourg has fewer because of foreigners proportion of 47.5% and many of them lives in the neighboring european countries. However, Germany is not only far behind in the Eurotransplant association with the number of organ donors, but Germany is also at the bottom in comparison with other European countries with comparable political, ethical, religious and social structures-are we so different from our European neighbors? Germany is a country with one of the best health care systems in the world, but not in the field of organ donation. In an international comparison of organ donation, even emerging economies are in a far better position than Germany. Thus, we should ask ourselves if a flaw in the system is leading to this organ donor shortage. But what is the cause and how can we change it? There is no single and general solution to this problem. There are many different points to consider and tackle. These include educating the population, indicating of the will to donate organs or its rejection, training physicians to recognize potential organ donors, support for transplant officers, and much more. In particular, however, thought should be given to an opt-out (presumed consent) solution. It is time to question the system of organ donation in Germany and to discuss it objectively.
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Safety of Direct-Acting Antiviral Therapy Regarding Renal Function in Post-Liver Transplant Patients Infected with Hepatitis C Virus and a 100% 12-Week Sustained Virologic Response-A Single-Center Study. Transplant Proc 2018; 50:1444-1450. [PMID: 29880368 DOI: 10.1016/j.transproceed.2018.02.062] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2017] [Revised: 02/20/2018] [Accepted: 02/20/2018] [Indexed: 12/11/2022]
Abstract
BACKGROUND Patients after liver transplantation (LT) with hepatitis C virus (HCV) infection often suffer from renal or hepatic impairment. Treating patients after LT with direct-acting antivirals (DAA) might result in decreasing renal function due to interaction of DAA and immunosuppressive therapy. In this single-center study we analyzed clinical parameters of 18 HCV-infected patients treated with DAA therapy after LT. METHODS The primary end points were change of renal function (glomerular filtration rate) and sustained virologic response 12 weeks after therapy (SVR12). For secondary end points, we investigated the influence of DAA therapy on transaminases, bilirubin, international normalized ratio, noninvasive fibrosis measurement, and Model for End-Stage Liver Disease (MELD) score. RESULTS Five out of 18 patients treated with DAA suffered from renal impairment stage 2, and 7 patients of renal impairment stage 3. Renal function at SVR12 was not influenced by preexisting renal impairment (P > .5), type of immunosuppressant (P > .5), or type of DAA regimen (P > .5). All patients reached SVR12. The levels of transaminases and bilirubin declined rapidly, as expected. Ten out of 18 patients already suffered from cirrhosis or liver fibrosis >F3 according to noninvasive measurement before initiation of treatment. Single-point acoustic radiation force impulse imaging improved in 9 patients (P = .012). In 7 patients, MELD score improved owing to the decrease of bilirubin levels. In 6 patients it worsened. CONCLUSIONS DAA therapy in LT patients was effective and safe in this single-center real-life cohort. Renal function was not influenced by the administered drug combinations, even in patients with preexisting renal impairment.
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Doppler Assessment of Diastolic Function Reflect the Severity of Injury in Rats With Chronic Heart Failure. J Card Fail 2017; 23:753-761. [PMID: 28801075 DOI: 10.1016/j.cardfail.2017.08.446] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 07/20/2017] [Accepted: 08/01/2017] [Indexed: 10/19/2022]
Abstract
OBJECTIVE For chronic heart failure (CHF), more emphasis has been placed on evaluation of systolic as opposed to diastolic function. Within the study of diastology, measurements of left ventricular (LV) longitudinal myocardial relaxation have the most validation. Anterior wall radial myocardial tissue relaxation velocities along with mitral valve inflow (MVI) patterns are applicable diastolic parameters in the differentiation between moderate and severe disease in the ischemic rat model of CHF. Myocardial tissue relaxation velocities correlate with traditional measurements of diastolic function (ie, hemodynamics, Tau, and diastolic pressure-volume relationships). METHODS AND RESULTS Male Sprague-Dawley rats underwent left coronary artery ligation or sham operation. Echocardiography was performed at 3 and 6 weeks after coronary ligation to evaluate LV ejection fraction (EF) and LV diastolic function through MVI patterns (E, A, and E/A) and Doppler imaging of the anterior wall (e' and a'). The rats were categorized into moderate or severe CHF according to their LV EF at 3 weeks postligation. Invasive hemodynamic measurements with solid-state pressure catheters were obtained at the 6-week endpoint. Moderate (N = 20) and severe CHF (N = 22) rats had significantly (P < .05) different EFs, hemodynamics, and diastolic pressure-volume relationships. Early diastolic anterior wall radial relaxation velocities as well as E/e' ratios separated moderate from severe CHF and both diastolic parameters had strong correlations with invasive hemodynamic measurements of diastolic function. CONCLUSION Radial anterior wall e' and E/e' can be used for serial assessment of diastolic function in rats with moderate and severe CHF.
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Abstract 86: Mapping and Inducing Ventricular Tachycardia in Cardiomyopathic Animal Models. Circ Res 2017. [DOI: 10.1161/res.121.suppl_1.86] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Introduction:
In the United States, one in three deaths is attributed to cardiovascular disease (CVD). With CVD, sudden cardiac death is a common cause of mortality, specifically by way of ventricular tachycardia (VT) and ventricular fibrillation. We propose the application of our custom software to evaluate the electrophysiologic (EP) properties of animal models of ischemic and non-ischemic dilated cardiomyopathies.
Methods:
Adult male Sprague-Dawley rats with left coronary artery ligation and adult male and female transgenic Fragile X cardiomyopathic mice were sedated with Inactin and Isoflurane, respectively, and underwent hemodynamic measurements and/or EP testing. Using a PowerLab system and LabChart software, three-lead electrocardiograms were recorded. Using a pressure catheter, hemodynamic parameters were calculated. Using a concentric microelectrode (World Precision Inc.), a clinical EP catheter (Bard Inc.), and custom MATLAB software, local epicardial monophasic action potentials (MAP) and local epicardial voltages were recorded. Using custom MATLAB software for programmed electrical stimulation (PES), VT was induced epicardially with a clinically-accepted drivetrain. Animals underwent eight equidistant ‘S1’ stimulations followed by a premature ‘S2’ stimulation. The S2 stimulation was decreased by 5 milliseconds until loss of capture, indicating the effective refractory period. Sustained ventricular tachycardia (sVT) has been defined as more than fifteen consecutive premature ventricular contractions.
Results:
The chronic heart failure (CHF) rats had documented hemodynamic heart failure with elevated LV EDPs, and decreased EFs. Mapping and PES was performed on the two groups of rats, namely CHF and Sham-operated. In the CHF group, 71% (27/39) of the rats exhibited sVT, while 0% (0/10) of the Sham-operated rats exhibited sVT. Mapping was also performed on the two groups of mice, namely Wild-Type and Fragile X.
Conclusions:
We have performed clinically-relevant EP studies in CHF rats and in Fragile X dilated cardiomyopathic mice. These EP studies demonstrate our ability to evaluate and validate the phenotypes of animal models of cardiomyopathies and demonstrate the potential to evaluate the effectiveness of new therapies.
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Abstract
Radiation cystitis (RC) is a common side-effect of radiation to the pelvis. Their clinical appearance as well as their degree of expression is manifold, as are the therapeutic options. However, in the absence of randomized examinations, recommendations are difficult. We differentiate between oral, systemic therapies, intravesical instillations and interventions as well as interventional, radiological and, as an ultima ratio, surgical treatments. This article provides an overview of the different treatment options with particular emphasis on the conservative-interventional therapy options.
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Die Schmelzkurven der Gase A, Kr, X, CH4, CH3D, CD4, C2H4, C2H6, COS and PH3 bis 200 Atm. Druck. Der Volumensprung beim Schmelzen. ACTA ACUST UNITED AC 2017. [DOI: 10.1515/zpch-1940-4602] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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In vivo Electrophysiological Study of Induced Ventricular Tachycardia in Intact Rat Model of Chronic Ischemic Heart Failure. IEEE Trans Biomed Eng 2016; 64:1393-1399. [PMID: 27608446 DOI: 10.1109/tbme.2016.2605578] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE The objective of this study was to define the clinical relevance of in vivo electrophysiologic (EP) studies in a rat model of chronic ischemic heart failure (CHF). METHODS Electrical activation sequences, voltage amplitudes, and monophasic action potentials (MAPs) were recorded from adult male Sprague-Dawley rats six weeks after left coronary artery ligation. Programmed electrical stimulation (PES) sequences were developed to induce sustained ventricular tachycardia (VT). The inducibility of sustained VT was defined by PES and the recorded tissue MAPs. RESULTS Rats in CHF were defined ( 0.05) by elevated left ventricular (LV) end-diastolic pressure (5 ± 1 versus 18 ± 2 mmHg), decreased LV + d P/dt (7496 ± 225 versus 5502 [Formula: see text] s), LV - dP/dt (7723 ± 208 versus 3819 [Formula: see text]), LV ejection fraction (79 ± 3 versus [Formula: see text]), peak developed pressure (176 ± 4 versus 145 ± 9 mmHg), and prolonged time constant of LV relaxation Tau (18 ± 1 versus 29 ± 2 ms). The EP data showed decreased ( 0.05) electrogram amplitude in border and infarct zones (Healthy zone (H): 8.7 ± 2.1 mV, Border zone (B): 5.3 ± 1.6 mV, and Infarct zone (I): 2.3 ± 1.2 mV), decreased MAP amplitude in the border zone (H: [Formula: see text] 1.0 mV, B: 9.7 ± 0.5 mV), and increased repolarization heterogeneity in the border zone (H: 8.1 ± 1.5 ms, B: 20.2 ± 3.1 ms). With PES we induced sustained VT (>15 consecutive PVCs) in rats with CHF (10/14) versus Sham (0/8). CONCLUSIONS These EP studies establish a clinically relevant protocol for studying genesis of VT in CHF. SIGNIFICANCE The in vivo rat model of CHF combined with EP analysis could be used to determine the arrhythmogenic potential of new treatments for CHF.
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Implantation of an Induced Pluripotent Stem Cell Derived Cardiomyocyte Tissue Engineered Patch Improves Left Ventricular Function and Electro-Mechanical Coupling in Rats with Heart Failure. J Card Fail 2016. [DOI: 10.1016/j.cardfail.2016.06.383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Abstract 71: Model of Induced Ventricular Tachycardia and Cardiac Electrophysiological Mapping. Circ Res 2016. [DOI: 10.1161/res.119.suppl_1.71] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Introduction:
We have developed a computer user interface able to provide prescribed programmed electrical stimulation (PES) to induce sustained-ventricular tachycardia (VT) in rats with chronic heart failure (CHF). We propose this program to examine the cardiac electrophysiology (EP) properties and arrhythmogenic potential in varying disease models and as a method of evaluating drug safety in an intact animal.
Methods:
Using custom MATLAB software developed in our laboratory, we performed monophasic action potential (MAP) recordings and initiated protocols to induce sustained-VT through right ventricular epicardium PES outputs. Studies were performed in adult male Sprague-Dawley rats (N=22) six weeks after left coronary artery ligation under anesthesia and open chest.
Results:
CHF was verified by standard hemodynamic and echocardiographic parameters as is standard in our laboratory. In the CHF group, 71% (10/14) of the rats exhibited sustained-VT in response to PES versus 0% (0/8) of Sham rats. MAP recordings taken prior-to and during VT induction provided examples of localized activity for arrhythmia mechanisms such as delayed afterdepolarizations. Mechanical alternans, electrical alternans, intermittent pulse generations, and pulseless electrical activity were all observed in this model. EP data analysis showed a decreased (p<0.05) electrogram amplitude in border and infarct zones (Healthy (H): 8.7 ±2.1 mV, Border: 5.3±1.6 mV, Infarct (I): 2.3±1.2 mV), a similar trend for MAP amplitudes, and an increased (p<0.05) repolarization heterogeneity in the border zone (H: 8.1±1.5 ms, B: 20.2±3.1 ms).
Conclusions:
We have developed a custom computer user interface capable of performing clinically relevant
in-vivo
EP studies in rats with CHF. This rat model reproduces common clinical prognosis factors such as mechanical alternans, electrical alternans, and pulseless electrical activity. These EP studies demonstrate this program’s ability to test the arrhythmogenic potential of pharmaceutic agents, biologics, and implantables in an intact animal model before clinical advancement. We introduce this program to study an animal model’s EP characteristics before, during, and after treatments for CHF, and potentially other disease states.
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Abstract 360: Implantation of an Induced Pluripotent Stem Cell Derived Cardiomyocyte Tissue Engineered Patch Improves Left Ventricular Function and Electro-mechanical Coupling in Rats With Heart Failure. Circ Res 2016. [DOI: 10.1161/res.119.suppl_1.360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background:
Chronic Heart Failure (CHF) is the leading cause of hospital readmissions and mortality in the US. Here we report the effects of surgically delivering a human bioengineered patch of human induced pluripotent stem cells derived cardiomyocytes (hiPSC-CMs) and fibroblasts on left ventricular (LV) function in rats with CHF. We evaluate improvements in LV systolic and diastolic function, electromechanical coupling and gene expression after patch implantation.
Methods:
Adult male Sprague-Dawley rats underwent left coronary artery ligation and were randomized to Sham (N=8), CHF (N=8-21), and CHF+hiPSC-CM patch (N=20-24). Heterogeneous hiPSC-CMs were seeded and co-cultured onto a vicryl matrix embedded with human dermal fibroblasts. Echocardiography was performed at 3 and 6 weeks post-randomization. Hemodynamic pressure measurements were performed at 6 weeks post-ligation with Millar solid state micromanometer pressure catheters. Open chest Electrophysiologic (EP) mapping was performed at 6 weeks post ligation. Gene expression was evaluated through qRT-PCR.
Results:
48 hours into culture hiPSC-CMs patches displayed synchronized and spontaneous contractions which developed in robustness over time. At maximal robustness, contractions were visualized across the full thickness of the construct. Contractions were recorded at 36
+
5 beats BPM. Three weeks after patch implantation (6 weeks post ligation) the hiPSC-CM patch decreased (P<0.05) LV EDP (45%), Tau (29%), E/e’ (23%) and increased (P<0.05), e’/a’ (36%) with trending improvements in EF (14%) and e’ (20%). EP studies show electro-mechanical coupling between the patch and the native myocardium with normal activation through the patch and increases (P<0.05) voltage amplitude in CHF versus hiPSC-CM patch treated rats (1±0.5 mV vs 6±1.5mV). Rats treated with the hiPSC-CM patch showed significant (P<0.05) fold expression of Cx43 (3.3), ANG-1 (13.63), VEGF (3.8), βMYH7 (6.4) and IGF-1 (22.9) versus control.
Conclusion:
Cardiac patch implantation with hiPSC derived cardiomyocytes is an effective and feasible method of treating CHF with improvements in systolic function, diastolic function, and electro-mechanical coupling in rats with CHF.
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[Expert recommendations: Hepatitis C and transplantation]. ZEITSCHRIFT FUR GASTROENTEROLOGIE 2016; 54:665-84. [PMID: 27429106 DOI: 10.1055/s-0042-107360] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
With the approval of new direct acting antiviral agents (DAA), therapeutic options for patients with chronic hepatitis C virus (HCV) infection are now generally available before and after liver transplantation (LT). Interferon-free DAA regimens are highly effective therapies and provide a good safety profile. However, the body of clinical evidence in this patient population is limited and the best treatment strategies for patients on the waiting list with (de)compensated cirrhosis and after LT are not well defined. The following recommendations for antiviral therapy in the context of LT are based on the currently available literature and clinical experience of experts in the field, and have been discussed in an expert meeting. The aim of this article is to guide clinicians in the decision making when treating patients before and after LT with DAAs.
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Leberversagen bei einem 65-jährigen Patienten aufgrund eines Influenza B getriggerten Makrophagenaktivierungssyndromes (MAS). ZEITSCHRIFT FUR GASTROENTEROLOGIE 2015. [DOI: 10.1055/s-0035-1559125] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Induced Pluripotent Stem Cell Derived Cardiomyocyte Scaffold Improves Electro-Mechanical Coupling and Left Ventricular Function in Rats With Heart Failure. J Card Fail 2015. [DOI: 10.1016/j.cardfail.2015.06.275] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract 425: Induced Pluripotent Stem Cell Derived Cardiomyocyte Tissue Engineered Scaffold Improves Left Ventricular Function and Electro-Mechanical Coupling in Rats with Heart Failure. Circ Res 2015. [DOI: 10.1161/res.117.suppl_1.425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background:
Chronic Heart Failure (CHF) is the leading cause of hospital readmissions in the United States. It may result from systolic or diastolic dysfunction, which often coexists. Here we report the effects of delivering human induced pluripotent stem cells derived cardiomyocytes (hiPSC-CMs) via a bioengineered patch on left ventricular function in rats with CHF.
Methods:
Adult male Sprague-Dawley rats underwent left coronary artery ligation and were randomized to Sham, CHF, and hiPSC-CM patch. High purity human hiPSC-CMs were obtained from Cellular Dynamics International, seeded and co-cultured onto a vicryl matrix embedded with human dermal fibroblasts. Echocardiography was performed at 3 and 6 weeks post-randomization. Hemodynamic pressure measurements were performed at 6 weeks post-ligation with Millar solid state micromanometer catheters. Open chest Electrophysiologic (EP) mapping was performed at 6 weeks post ligation.
Results:
Patches constructed with hiPSC-CMs displayed synchronized and spontaneous contractions within 48hrs of culture which developed in robustness over time. At maximal robustness, contractions were visualized across the full thickness of the construct. Contractions were recorded at 36+5 beats BPM. Three weeks after implantation, the hiPSC-CM patch decreased LV EDP (45%), Tau (29%), E/e’ (23%) and increased, EF (14%), e’ (20%), and e’/a’ (36%) versus CHF. EP studies show electro-mechanical coupling between the patch and the native myocardium with normal activation through the patch and increases (P<0.05) voltage amplitude in CHF versus hiPSC-CM patch treated rats (1±0.5 mV vs 6±1.5mV).
Conclusion:
Cardiac patch implantation with human iPSC derived cardiomyocytes is an effective and feasible method of treating CHF with improvements in systolic function, diastolic function, and electro-mechanical coupling in rats with CHF.
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Development and Use of a Human Induced Pluripotent Stem Cell Derived Cardiac Construct. J Card Fail 2014. [DOI: 10.1016/j.cardfail.2014.06.237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Abstract 9: Development And Testing Of A Human Induced Pluripotetent Stem Cell Derived Cardiac Scaffold. Circ Res 2014. [DOI: 10.1161/res.115.suppl_1.9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Introduction:
Cell-based regenerative therapies hold promise in providing treatment strategies for heart failure. Previous work from our laboratory has shown that tissue engineered cardiac constructs enhance improvements in cardiac function by providing structural and nutrient support, potentially aiding in transplanted cell survival, integration and re-population of injured tissues. Our current studies focus on the development and testing of second-generation cardiac constructs utilizing high purity human induced pluripotent stem cell derived cardiomyocytes (hiPSC-CMs).
Methods:
High purity hiPSC-CMs were seeded and co-cultured onto a vicryl matrix embedded with biologically active human dermal fibroblasts. The hiPSC-CM constructs were maintained at 37°C and 5% CO2. Patches were constructed maintained as described for both in vitro and in vivo evaluation. Patches for in vivo evaluation were seeded, cultured and implanted onto the rat heart 3 weeks after left coronary artery ligation to assess improvements in LV function. Patches prepared for in vitro evaluation were seeded and cultured 1-10 days.
Results:
Patches constructed with hiPSC-CMs displayed synchronized and spontaneous contractions within 48hrs of culture which developed in robustness over time. At maximal robustness, contractions were visualized across the full thickness of the construct. Contractions were recorded at 36+5 beats BPM. In addition hiPSC-CM constructs respond to electrical stimulation with increased rate of contraction while maintaining their synchrony. Post pacing, the hiPSC-CM constructs return to their intrinsic rhythm.
Conclusion:
These findings show that high purity hiPSC-CMs can be seeded and co-cultured onto a vicryl and fibroblast construct in manner permitting adhesion and electromechanical coupling of the hiPSC-CMs to form a fully contractile construct. This is supported by the observation that the hiPSC-CMs contract spontaneously and in a synchronized manner in a directional fashion.
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Implantation of an Electrically Coupled Cardiomyocyte Scaffold Improves Left Ventricular Ejection Fraction in Rats 18 Weeks after Implantation. J Card Fail 2013. [DOI: 10.1016/j.cardfail.2013.06.196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Transfusionsstrategien: Leitliniengerechte Diagnostik und Therapie. TRANSFUSIONSMEDIZIN 2012. [DOI: 10.1055/s-0031-1283905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Abstract
Little is known about the ability of hepatitis C virus (HCV) to alter early innate immune responses in infected patients. Previous studies have shown that natural killer (NK) cells are functionally impaired after interaction of recombinant HCV glycoprotein E2 with the co-stimulatory CD81 molecule in vitro; however, the functional consequences of a prolonged contact of NK cells with HCV particles have remained unclear. We have examined the phenotypes of purified, interleukin-2-activated NK cells from healthy donors and HCV genotype 1b patients after culture for 5 days with HCV pseudoparticles (HCVpp) and serum samples containing HCV genotype 1b. NK cells from healthy donors and chronic HCV patients were found to up-regulate receptors associated with activation (NKp46, NKp44, NKp30, NKG2D), while NK receptors from the killer cell immunoglobulin-like receptor family (KIR/CD158), predominantly having an inhibitory function, were significantly down-modulated after culture in the presence of HCV particles compared with control cultures of NK cells. HCV-infected sera and HCVpp elicited significantly higher secretion of the NK effector lymphokines interferon-γ and tumour necrosis factor-α. Furthermore, HCV stimulated the cytotoxic potential of NK cells from normal donors and patients. The enhanced activation of NK cells after prolonged culture with HCVpp or HCV-containing sera for 5 days suggests that these innate effector cells may play an important role in viral control during early phases of HCV infection.
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Cytomegalovirus Infection After Liver Transplantation Incidence, Risks, and Benefits of Prophylaxis. Transplant Proc 2010; 42:2634-41. [DOI: 10.1016/j.transproceed.2010.04.025] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2009] [Revised: 10/16/2009] [Accepted: 04/21/2010] [Indexed: 01/08/2023]
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Chronic anemia masking a primary large B-cell lymphoma of the small intestine, finally diagnosed by double-balloon enteroscopy. Endoscopy 2008; 40 Suppl 2:E149. [PMID: 18633862 DOI: 10.1055/s-2007-995772] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
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Transperitoneal, Hand-Assisted Laparoscopic Donor Nephrectomy: Surveillance of Renal Function by Immune Monitoring. Transplant Proc 2008; 40:895-901. [DOI: 10.1016/j.transproceed.2008.03.079] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Esophagitis in an adolescent patient with Crohn's disease after changing treatment from prednisolone to budesonide. ZEITSCHRIFT FUR GASTROENTEROLOGIE 2005; 42:1179-81. [PMID: 15508059 DOI: 10.1055/s-2004-813548] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Studies have demonstrated that budesonide is effective in the treatment of active Crohn's disease. Due to its extensive hepatic metabolism, budesonide has much lower adverse events compared to prednisolone. Consequently, the low systemic availability restricts its application to Crohn's disease of the terminal ileum and the colon. Esophageal ulceration is a rare complication of Crohn's disease. This article describes the case of a young lady who presented at the age of 16 with active Crohn's disease of the terminal ileum and the colon without dysphagia or pain in the chest. Her disease was successfully treated with prednisolone for almost two years. Because of weight gain, acne, and moon face she was switched to budesonide. A few days later she presented with intractable pain of the esophagus, dysphagia, and inability to eat. Endoscopy demonstrated aphthous ulcerations of the esophagus and the histology was compatible with Crohn's disease. After two weeks of treatment with prednisolone all symptoms resolved and at follow-up gastroscopy ulcers had disappeared.
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A cart cage for transferring macaques, capuchins, and small dogs. Lab Anim (NY) 2001; 30:45-6. [PMID: 11385727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
A novel mobile monkey transport cart cage allows ease of handling, safety, secure holding, good visual access to the monkeys, room for large macaques, and ease of assembly, all at a modest cost.
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Pankreaspseudozysten: ein Beitrag zur Differentialtherapie. Visc Med 1999. [DOI: 10.1159/000012599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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[Application possibilities of laser surgery in veterinary medicine. 3: Literature review and some case reports]. TIERARZTLICHE PRAXIS 1997; 25:289-302. [PMID: 9312886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The transmission of the laser beam trough flexible fibers enables an endoscopic application. Since this technique is minimal invasive and often does not require general anaesthesia there is an increasing interest in the use of laser techniques-for example in equine upper respiratory tract surgery. This paper gives a review about reported laser application in the different fields of veterinary surgery with emphasis on laser practice in dermatology, ophthalmology and endoscopic laser application.
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[Possibilities for the us of laser surgery in veterinary medicine. Part 2: Effects of laser beams on tissue]. TIERARZTLICHE PRAXIS 1996; 24:331-6. [PMID: 9012015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The effect of a certain laser beam on tissue is dependent on the different properties of the tissue. The various kinds of laser radiation are absorbed from different components of an organ. Only where absorption takes place there will be a transformation of the energy of radiation to other forms of energy and changes in tissue will occur. The arising thermal energy not only heats the area exposed to the laser beam but the surrounding tissue. The extent of the heating effect on tissue is due to properties of the tissue, e.g. the degree of blood supply and with it the draining of heat, and the parameters of the laser system, e.g. time of exposition and power of radiation. By increasing power of radiation the effect will be an unspecific heat stimulation, coagulation of tissue up to vaporization of tissue. By using different ways of transmission the effects produced by laser will change and can be adapted to various medical and anatomical requirements.
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[Application of laser surgery in veterinary medicine. 1. Fundamentals]. TIERARZTLICHE PRAXIS 1995; 23:432-6. [PMID: 8585052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
This article will outline the key words of laser physics. Albert Einstein set the basics of laser physics by characterizing the principles of stimulated emission of radiation in 1914. An excited atom can change from these excited energy level to a lower level by emitting energy in form of photons. If this photon strikes another excited atom, it will stimulate emission of another photon. By these action two identical photons will emerge. An optical resonator is used to amplify the stimulated light emission coming from a laser medium. Laser differs from other light sources in three important properties: coherence, collimation, and monochromasia.
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Abstract
The stereoselectivity of the in vitro conversion of isoprene by liver enzymes of rats and mice was determined. Isoprene was epoxidized by cytochrome P450 of rats and mice to 2-isopropenyloxirane and 2-methyl-2-vinyloxirane with slight but different product enantioselectivity. Only with mouse liver microsomes was a distinct regioselectivity observed. Both monooxiranes were further epoxidized to 2-methyl-2,2'-bioxirane with substrate enantioselectivity, product diastereoselectivity, and with product enantioselectivity. The epoxide hydrolase-catalyzed hydrolysis with rat and mouse liver microsomes occurs with substrate enantioselectivity. A better kinetic resolution was found for 2-isopropenyloxirane than for 2-methyl-2-vinyloxirane. While 2(R)-isopropenyloxirane was conjugated preferentially with glutathione, catalyzed by glutathione S-transferase, no enantiomer differentiation takes place in the case of 2-methyl-2-vinyloxirane.
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[Post-cholestatic hypercholeresis in a patient with malignant obstruction of the bile ducts]. SCHWEIZERISCHE MEDIZINISCHE WOCHENSCHRIFT 1993; 123:1351-3. [PMID: 8342004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Increased choleresis of up to 4950 ml per day was observed after positioning of a PTCD in a patient with complete biliary obstruction due to a malignant tumor. Bile secretion could be temporarily reduced to 15% of the initial flow rate by intravenous administration of somatostatin. Simultaneously, the concentration of bile acids increased from 1.2 to 6.2 mmol/l, whereas the concentrations of electrolytes remained constant. Cholic acid had no influence on bile secretion. To safeguard the patient from excessive loss of fluid and electrolytes, the drained bile was reinfused into the duodenum via a PEG.
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[Meat from the nutritional medicine viewpoint]. ZEITSCHRIFT FUR DIE GESAMTE INNERE MEDIZIN UND IHRE GRENZGEBIETE 1993; 48:29-34. [PMID: 8442376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
As in all forms of food, contaminants can also be present in meat. Because of the growing awareness of ecological and health issue, more tests with sophisticated equipment are now being implemented, thus reducing the risk of consuming contaminated meat. Meat has become the most heavily inspected form of food. In contrast to vegetable matter, animals can discharge many contaminants. Meat, with the exception of the liver and kidneys, is therefore less likely to be contaminated than vegetables. Facts show that meat is a highly nutritious food which, if consumed moderately, can contribute to our well-being. Meat contains the right combination of amino acids for protein synthesis in the human body, and especially it contains plenty of essential amino acids. Above all, meat contains many vitamins, trace elements, and iron. Large amounts of these substances are particularly necessary for growing children and people who are doing hard physical work. A reduction of meat consumption is only necessary in the case of a few illnesses. Some other illnesses actually require an increase in protein, and thus an increase in meat in the diet.
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Demonstration of sensitized lymphocytes to trimethoprim/sulfamethoxazole and ofloxacin in a patient with cholestatic hepatitis. J Hepatol 1992; 15:262-3. [PMID: 1506646 DOI: 10.1016/0168-8278(92)90045-q] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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[Fatal shock following metamizole]. Dtsch Med Wochenschr 1989; 114:443. [PMID: 2707128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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[Dorso-cranial liver resection with hepato-atrial anastomosis. An alternative to liver transplantation or the surgical procedure of choice in Budd-Chiari syndrome?]. Dtsch Med Wochenschr 1988; 113:1022-4. [PMID: 3289876 DOI: 10.1055/s-2008-1067761] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Surgery was required for a 23-year-old woman with rapidly progressive reduction in liver function and treatment-resistant ascites due to Budd-Chiari syndrome. A dorsocranial liver resection with hepatoatrial anastomosis was performed. The postoperative course has been satisfactory, demonstrating that this method should be seriously considered in the treatment of Budd-Chiari syndrome.
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Is albumin synthesis regulated by the colloid osmotic pressure? Effect of albumin and dextran on albumin and total protein synthesis in isolated rat hepatocytes. KLINISCHE WOCHENSCHRIFT 1986; 64:23-8. [PMID: 2419634 DOI: 10.1007/bf01721577] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
In order to study the influence of the colloid osmotic pressure on albumin and total liver protein synthesis, rat hepatocytes were isolated by collagenase perfusion and incubated in Krebs-Ringer-buffer for 4 h. The colloid osmotic pressure produced by different bovine serum albumin (BSA) or dextran 60 concentrations varied from 3 to 80 mm Hg. A physiological colloid osmotic pressure of 20 mm Hg was obtained with 5.7 g BSA or 3.7 g dextran 60 per 100 ml of buffer. Albumin synthesis was measured by Laurell rocket immunoelectrophoresis. Total liver protein and total secretory protein synthesis were determined by the measurement of 1-14C-leucine incorporation. Albumin synthesis was not primarily regulated by the colloid osmotic pressure as was demonstrated by a lack of inhibition after addition of BSA. There was no significant influence of the oncotic pressure on the incorporation of 14C-leucine into total liver proteins. The incorporation into total secretory proteins was inhibited by an increasing colloid osmotic pressure, mediated either by BSA or dextran, suggesting an inhibition of the secretion of plasma proteins other than albumin.
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Treatment of cystic echinococcosis (Echinococcus granulosus) with mebendazole: assessment of bound and free drug levels in cyst fluid and of parasite vitality in operative specimens. Eur J Clin Pharmacol 1985; 28:279-85. [PMID: 4007032 DOI: 10.1007/bf00543324] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Chemotherapy of the larval stage of Echinococcus granulosus in man with high oral doses of mebendazole has only been partly successful. In order to improve effective pharmacotherapy of this disease with mebendazole, the optimal time for blood sampling has been assessed and the mebendazole concentrations acting on the parasite have been compared with their viability. The optimal time for blood sampling was analysed in 14 patients during longterm treatment with mebendazole. The plasma level 4 h after the morning dose exhibited the best correlation with the average 24-h concentration, suggesting that the plasma level should be monitored 4 h after the morning dose. In 22 patients undergoing surgery for hydatid disease, the mebendazole concentration in cyst fluid was significantly correlated with its plasma level 4 h after the morning dose. In 13 of them the free drug concentration was determined by equilibrium dialysis and it was almost identical with the free mebendazole concentration in plasma. Results of viability tests in 12 cases revealed viable cysts in 6 cases and possibly viable cysts in 6 other cases. Even patients treated for more than 12 months still had viable cysts.
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[Analgesics and antiphlogistics in dentistry]. SCHWEIZERISCHE MONATSSCHRIFT FUR ZAHNMEDIZIN = REVUE MENSUELLE SUISSE D'ODONTO-STOMATOLOGIE = RIVISTA MENSILE SVIZZERA DI ODONTOLOGIA E STOMATOLOGIA 1984; 94 Spec No:971-8. [PMID: 6334889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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The N-terminal propeptide of collagen type III in serum reflects activity and degree of fibrosis in patients with chronic liver disease. Hepatology 1984; 4:830-4. [PMID: 6479851 DOI: 10.1002/hep.1840040505] [Citation(s) in RCA: 140] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
To evaluate the diagnostic significance of the collagen Type III (Col 1-3) N-terminal propeptide of procollagen Type III, with respect to activity and degree of liver fibrosis, Col 1-3 serum concentrations were measured in 111 patients with chronic liver diseases and in 60 patients were correlated with liver histology and morphometry. Col 1-3 was measured by a specific radioimmunoassay. Biopsies were read without knowledge of diagnosis. Periportal and intralobular lesions were assessed semiquantitatively by allocating 1 of 4 severity grades to each parameter. All portal areas were measured morphometrically. Compared to 27 normal controls, Col 1-3 concentrations were significantly elevated in patients with untreated chronic active hepatitis, cirrhosis and primary biliary cirrhosis, but not in chronic persistent hepatitis or fatty liver. Morphometrically measured portal tract area significantly correlated with Col 1-3 plasma levels. Among the semiquantitatively measured periportal lesions, the number of fibroblasts exhibited the closest relationship with Col 1-3 levels; there was no relationship between Col 1-3 levels and intralobular lesions. These data suggest that Col 1-3 serum levels reliably reflect the activity and degree of liver fibrosis and are useful along with liver biopsy in follow-up of patients with chronic liver disease.
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Long-term follow-up of serum N-terminal propeptide of collagen type III levels in patients with chronic liver disease. Hepatology 1984; 4:835-8. [PMID: 6479852 DOI: 10.1002/hep.1840040506] [Citation(s) in RCA: 62] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
To evaluate the diagnostic and prognostic significance of the N-terminal propeptide of collagen Type III (Col 1-3) in chronic liver disease, the peptide level was measured in the serum of 4 patients with primary biliary cirrhosis, 5 with chronic persistent hepatitis, 12 with chronic active hepatitis, and 1 with autoimmune hepatitis, for a period of 2 to 10 years and compared with liver function and histology. In primary biliary cirrhosis, Col 1-3 peptide levels were always elevated, regardless of medical therapy; however, after liver transplantation in one patient, the Col 1-3 peptide level decreased. In chronic persistent hepatitis, the peptide level fluctuated around the upper limit of normal. Among patients with chronic active hepatitis, the Col 1-3 peptide level normalized in 2 patients during remission, but was elevated in 7 patients who developed cirrhosis. Only in a patient with autoimmune hepatitis was the Col 1-3 peptide level normal, although the patient developed cirrhosis during prednisone therapy. When prednisone was withdrawn, the Col 1-3 peptide level increased. The data suggest that the serum Col 1-3 peptide may estimate the course of liver fibrosis in chronic liver disease and has prognostic value, particularly in chronic active hepatitis. Persistent elevation suggests ongoing fibrosis and development of cirrhosis; normalization suggests remission.
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Quasi-elastic light scattering studies of native hepatic bile from the dog: comparison with aggregative behavior of model biliary lipid systems. Biochemistry 1984; 23:1994-2005. [PMID: 6722132 DOI: 10.1021/bi00304a018] [Citation(s) in RCA: 83] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Using quasi-elastic light scattering ( QLS ), we have characterized the macromolecular components in hepatic bile obtained from the dog and compared these results with data from model bile solutions containing the bile salt (BS) sodium taurocholate (TC), egg lecithin (L), and cholesterol (Ch). Native bile samples were obtained by direct catheterization of the common bile duct in a previously cholecystectomized dog fitted with a Thomas duodenal cannula. Hepatic bile was sampled during three secretory states: (A) unstimulated "fasting" bile, (B) "stimulated" secretion during an intravenous TC infusion, and (C) "secretin-stimulated" secretion. All three samples had comparable molar ratios of L/BS (0.21 +/- 0.03) and Ch/L (0.027 +/- 0.006) but differed in the total lipid concentration (BS + L + Ch): (A) 13.1 +/- 0.8, (B) 6.7 +/- 0.8, and (C) 3.0 +/- 0.4 g/dL. From the QLS autocorrelation functions measured on samples B and C, three macromolecular components (denoted 1 alpha, 1 beta, and 2) were resolved. Component 1 alpha (hydrodynamic radius R1 alpha = 10 +/- 2 A) is comparable in size to the micellar aggregates of model systems. Component 1 beta (R1 beta = 67 +/- 7 A) appears to reflect an average of biliary proteins. Component 2 (R2 = 650 +/- 15 A) is a trace component whose size and sedimentation behavior are compatible with those of the canalicular membrane vesicles postulated to be present in bile [ Godfrey , P. P., Warner, M. J., & Coleman , R. (1981) Biochem. J. 196, 11]. Serial dilution of the B and C bile samples with Tris buffer (0.15 M NaCl, pH 8.0) showed a remarkable similarity in the behavior of the 1 alpha component as compared to the mean hydrodynamic radius Rh of similarly diluted model bile solutions. When a critical dilution factor, d gamma, is reached, Rh increases abruptly from approximately 30 to approximately 400 A. Above a second dilution factor, d alpha, it then decreases to a value of approximately 150 A. Similar results were obtained on sample A but were shifted to higher dilutions. Such behavior is consistent with the presence of "mixed disk" micelles [ Mazer , N. A., Benedek , G. B., & Carey, M. C. (1980) Biochemistry 19, 601] in native bile which undergo a micelle-to-vesicle transition upon dilution. From the d gamma and d alpha values, estimates of the intermicellar bile salt concentrations were made for all three samples (range 1.4-6.2 mM) which agree well with previous experimental results on model and native bile. These studies offer compelling evidence for the existence of micellar aggregates in native bile whose size, structure, and equilibria are similar to those found in model bile solutions.
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The hexa- and pentapeptide extension of proalbumin: lack of peptide-induced histamine-releasing activity by this hexapeptide in rat mast cells and human leucocytes. Immunol Lett 1984; 8:23-5. [PMID: 6204936 DOI: 10.1016/0165-2478(84)90099-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
It is well documented that small basic peptides with lipophilic counterparts induce non-cytolytic histamine release particularly from rat peritoneal mast cells, and to a lesser extent from human leukocytes. Since pro-albumin hexapeptide with its lipophilic core also exhibits a high percentage of basic amino acid residues, it was thought valid to investigate its potential histamine releasing activity using the above-mentioned cell systems. Results show that the peptide failed in both cell types to induce histamine release, or to inhibit IgE mediated or anaphylatoxin induced histamine release up to concentrations of 10(-4) M.
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Abstract
The human serum albumin gene was analyzed by restriction endonuclease mapping of chromosomal DNA isolated from a patient with congenital analbuminemia. Following digestion with a variety of restriction endonucleases, the DNA from this individual produced the same fragments with homology to a serum albumin cDNA probe as did a control DNA specimen. Therefore, the genetic condition of congenital analbuminemia is not caused by any gross structural rearrangement or deletion of the gene itself, but may result from an abnormality in the gene's fine structure, perhaps affecting regulation or processing of the primary RNA transcript.
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Abstract
Analbuminemia (idiopathic hypoalbuminemia) is a rare congenital anomaly of albumin characterised by very low levels of this protein. Only 21 cases have been reported in the literature. The lack of albumin is "compensated" by increased amounts of various circulating plasma proteins. Other not well understood regulatory mechanisms are responsible for the absence of severe clinical consequences. Clinical aspects, genetics and pathophysiology of this disease are discussed.
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Turnover of autologous alpha 1-antitrypsin in a patient with congenital analbuminemia. KLINISCHE WOCHENSCHRIFT 1983; 61:547-52. [PMID: 6603561 DOI: 10.1007/bf01486844] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Despite very low amounts of albumin (1.7 mg/100 ml) the total plasma protein concentration of a patient with congenital analbuminemia was only slightly reduced to 6.3 g/100 ml. The lack of albumin is compensated by high concentrations of many other plasma proteins. Among the plasma proteins measured, alpha 1-antitrypsin showed a particularly high level. To investigate the underlying mechanism of this increase we purified plasma alpha 1-antitrypsin from the patient, labelled it with 125I, and studied its turnover in the analbuminemic patient and two normal volunteers. A half-life of 15 days in the patient compared with 7.5 and 8 days in the normal volunteers was found. The calculated synthesis rate of alpha 1-antitrypsin was about twice as high in the patient as in the controls. Therefore, both a longer half-life and an increased synthesis rate contribute to the high level of alpha 1-antitrypsin in the plasma of the analbuminemic patient.
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Comparison of gastrointestinal loss of alpha-1-antitrypsin and chromium-51-albumin in Ménétrier's disease and the influence of ranitidine. Digestion 1983; 26:192-6. [PMID: 6307792 DOI: 10.1159/000198889] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
In a 37-year-old patient with Ménétrier's disease, 51Cr-albumin and alpha 1-antitrypsin (alpha 1-AT) output was measured simultaneously in gastric juice and feces. While the 51Cr-albumin studies demonstrated a threefold increase in gastrointestinal protein loss, alpha 1-AT was found in normal quantities in gastric juice and feces. The histamine H2 antagonist, ranitidine, led to a marked reduction in gastric protein loss, as evidenced by decreased 51Cr activity in the stomach. Studies of protein loss in the gastric juice during pentagastrin stimulation (6 micrograms/kg/h) showed that the 51Cr-albumin output paralleled the volume secreted, whereas alpha 1-AT decreased with lower pH values, not being detectable below pH 3. This probably results from peptic degradation of alpha 1-AT at low pH. We conclude that fecal alpha 1-AT determination cannot be used for the assessment of protein-losing gastropathy in patients who are not achlorhydric.
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Carbonyldiimidazole/1-hydroxybenzotriazole activation in polymer phase synthesis of the arginine rich proalbumin hexapeptide extension. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1983; 21:100-6. [PMID: 6826277 DOI: 10.1111/j.1399-3011.1983.tb03083.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The synthesis on different polymer phases of Arg-Gly-Val-Phe-Arg-Arg, the proalbumin extension, is reported. The peptide was prepared both on a 0.5% cross-linked polystyrene gel containing 2-oxoethyl bromide anchor functions and on a 1% cross-linked chloromethyl polystyrene. For temporary blocking of the amino groups we utilized the 2-(3,5-dimethoxyphenyl) propyl-(2)-oxycarbonyl (Ddz). The guanidino groups of the three arginine moieties were protected by the 4-toluenesulfonyl (Tos) group. As coupling procedure we used 1 equiv. carbonyldiimidazole (CDI)/2 equiv. 1-hydroxybenzotriazole (HOBt). The C-terminal activation of the Ddz-amino acids with CDI/HOBt made it possible to recover the excess Ddz-amino acids in 60-80% yield. We also investigated different procedures to cleave the 2-oxoethyl ester bond between the peptide and the polymer. This bond was completely stable against trifluoromethanesulfonic acid and was split by 1 N triethylamine in methanol/dioxane 1:1 (v/v) + 1 vol% 1 N NaOH. The optical rotation and HPLC properties of Arg-Gly-Val-Phe-Arg-Arg from this synthesis are identical to the product from a different synthesis published earlier.
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