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101.
102.
Abstract Hyperdynamic circulation and portal hypertension characterize acute on chronic liver failure (AoCLF), partially because of circulating mediators. Molecular Absorbents Recirculating System (MARS) may remove some of these substances. The objective of this study was to evaluate the effect of MARS on portal pressure, systemic haemodynamic and endogenous vasoactive systems. MARS treatment was performed in four patients with AoCLF (mean age 36.2 ± 3.1 years; Child–Pugh C 11 ± 1.8 points; three AAH and one NASH). Systemic and splanchnic haemodynamic measurements were performed before and after each session. Plasmatic renin activity (PRA) and NE were measured at baseline, at the end of the sessions and 10 days after MARS. All patients had severe portal hypertension (HVPG = 23 ± 7 mmHg) and pronounced hyperdynamic circulation (MAP 77.8 ± 11.7 mmHg; CO 11.2 ± 1.6 L/min; SVRI 478.5 ± 105 dyne s/cm5). HVPG decreased at the end of the first session in all patients (23 ± 7 mmHg vs 17.3 ± 9.9 mmHg; P = 0.05; mean decrease 32 ± 24%) because of a decrease in WHVP (40.7 ± 5.6 mmHg vs 34 ± 9.6 mmHg; P = 0.025; mean decrease 18 ± 19%). MARS significantly attenuated hyperdynamic circulation as shown by a decrease in CO (11.2 ± 1.6 L/min vs 9.4 ± 2.1 L/min; mean decrease 12.3%), with an increase in MAP (77.8 ± 11.7 mmHg vs 84.2 ± 8 mmHg; mean increase 9.2%) and in SVRI (478.5 ± 105 dyne s/cm5 vs 622 ± 198 dyne s/cm5; mean increase 41%). PRA and NE decreased significantly (14.2 ± 17.2 ng/mL/h vs 3.7 ± 3.4 ng/mL/h; 1319 ± 1002 pg/mL vs 617 ± 260 pg/mL, respectively). The NE decrease was correlated to HVPG decrease (r = 1, P = 0.01). MARS decreases portal hypertension and ameliorates hyperdynamic circulation in patients with AoCLF, probably mediated by clearance of vasoactive substances. Further studies are necessary to confirm these results.  相似文献   
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104.
We summarize the clinical history and laboratory results following the introduction of tenofovir among 6 patients coinfected with human immunodeficiency virus (HIV) and hepatitis B virus (HBV) who presented with severe liver disease while receiving lamivudine-based highly active antiretroviral therapy. In all cases, the introduction of tenofovir led to a sustained undetectable HBV and HIV loads, with marked clinical and laboratory improvement in liver function. We provide supporting evidence for the role of tenofovir in the management of advanced HBV infection in HIV-positive patients after the development of lamivudine resistance.  相似文献   
105.
There is evidence that following the recommendations on screening and treatment of tuberculosis infection does not completely prevent the onset of tuberculosis in patients with inflammatory bowel disease. This fact, and the increasing use of new biologics and immunomodulators, has led the Spanish Group Working on Crohn's Disease and Ulcerative Colitis to update their recommendations for the prevention of tuberculosis in patients with inflammatory bowel disease. Diagnostic methods for latent tuberculosis infection, different scenarios in which screening is to be performed, strategies to reduce the risk of tuberculosis once biological treatment is initiated and chemoprophylaxis guidelines for latent tuberculosis infection are reviewed, as well as the management of active tuberculosis during biological treatment. Finally, there is a summary of the current recommendations within the paper and in an algorithm.  相似文献   
106.
107.
Summary Anticardiolipin antibodies (ACA) frequently appear in patients with autoimmune disorders such as systemic lupus erythematosus, and have also been detected in infections, neoplasia, the primary antiphospholipid syndrome, in association with certain medications and also in subjects without apparent disease. Recently, anticardiolipin antibodies have been described in the acquired immunodeficiency syndrome. Eighty-four human immunodeficiency virus (HIV)-infected patients were studied to assess the influence of risk factors for HIV infection and of the stage of HIV-1 infection on the prevalence of IgG-ACA in HIV-seropositive patients. Patients were divided in two groups, one composed of 38 asymptomatic HIV-infected individuals and the other of 46 AIDS patients. A control group of 42 healthy HIV-negative blood donors was also studied. All subjects of the control group were IgG-ACA-negative. Of the 84 HIV-positive patients, 50 were IgG-ACA positive (59.5%) and 34 IgG-ACA negative (40.5%). None of the HIV-positive patients presented any thromboembolic phenomena. No significant differences were found with respect to sex, risk factors and stage of disease when the presence of IgG-ACA in HIV-positive patients was considered. ACA does not appear to be a pronostic marker in HIV-1-infected subjects. The presence of IgG-ACA is probably related to HIV-1-infection itself, and is indicative of impaired humoral immunity in these patients.
Anticardiolipin-Antikörper und erworbenes Immunschwächesyndrom: Prognostischer Marker oder Assoziation mit HIV-Infektion?
Zusammenfassung Anticardiolipin-Antikörper (ACA) treten häufig bei Patienten mit Autoimmunkrankheiten wie Lupus erythematodes auf, wurden aber auch im Zusammenhang mit Infektionen, Neoplasien, dem primären Antiphospholipid-Syndrom und bestimmten Medikamenten beobachtet oder bei Personen ohne jegliche erkennbare Erkrankung. Kürzlich wurden Anticardiolipin-Antikörper bei erworbener Immunschwäche beschrieben. Um den Einfluß von Risikofaktoren für eine HIV-Infektion und des Krankheitsstadiums auf die Prävalenz von IgG- ACA zu ermitteln, wurden 84 HIV-infizierte Patienten untersucht. Sie wurden in zwei Gruppen, 38 asymptomatische HIV-Infizierte und 46 AIDS-Patienten unterteilt und mit einer Kontrollgruppe von 42 gesunden, HIV-negativen Blutspendern verglichen. Die Kontrollpersonen waren alle ACA-negativ. Aus der Gesamtgruppe der 84 HIV-positiven Patienten wiesen 50 ACA-IgG auf (59,5%), 34 waren negativ (40,5%). Thromboembolische Phänomene waren bei keinem dieser HIV-positiven Personen zu beobachten. Es bestand keine signifikante Differenz zwischen positiven und negativen ACA-Befunden hinsichtlich Geschlecht der Patienten, Risikofaktoren und Krankheitsstadium der HIV- Infektion. Bei HIV-1-Infizierten scheint der Nachweis von ACA keine prognostische Bedeutung zu haben. Die Antikörper sind wahrscheinlich mit der HIV-Infektion selbst assoziiert und ein Zeichen für die gestörten humoralen Immunfunktionen dieser Patienten.
  相似文献   
108.
To determine whether fish have an insulin-like growth factor II/mannose 6-phosphate (IGF-II/M6-P) receptor similar to that of mammals, we have performed binding, cross-linking, and immunoprecipitation experiments with wheat-germ-agglutinin- and mannose 6-phosphate (M6-P)-affinity-purified receptor preparations from fish embryos. In both receptor preparations, IGF-II binding was specific, because labeled IGF-II could only be completely displaced by cold IGF-II but not by IGF-I or insulin. Labeled IGF-II bound to a protein with a molecular mass of approximately 250 kDa, which could be immunoprecipitated with an antibody against the rat IGF-II receptor. IGF-II stimulated tyrosine kinase activity in wheat germ agglutinin preparations and was more potent than insulin or IGF-I, but neither peptide stimulated tyrosine kinase activity in M6-P preparations. Two fish cell lines (CHSE-214 and EPC) were used to confirm the IGF-II binding data obtained in the receptor preparations, revealing the presence of highly specific IGF-II binding and the absence of insulin binding. Furthermore, a decrease of the IGF-I receptors on the cell surface did not alter IGF-II binding in EPC cells. In conclusion, we have detected the presence of IGF-II/M6-P receptors in fish embryos that are similar in structure and specificity for their ligand to those found in mammals.  相似文献   
109.

Purpose

To analyze the influence of adding gentamicin to a regimen consisting of β-lactam or vancomycin plus rifampicin on survival in patients suffering from Staphylococcal prosthetic valve endocarditis (SPVE).

Methods

From January 2008 to September 2016, 334 patients with definite SPVE were attended in the participating hospitals. Ninety-four patients (28.1%) received treatment based on β-lactam or vancomycin plus rifampicin and were included in the study. Variables were analyzed which related to patient survival during admission, including having received treatment with gentamicin.

Results

Seventy-seven (81.9%) were treated with cloxacillin (or vancomycin) plus rifampicin plus gentamicin, and 17 patients (18.1%) received the same regimen without gentamicin. The causative microorganism was Staphylococcus aureus in 40 cases (42.6%) and coagulase-negative staphylococci in 54 cases (57.4%). Overall, 40 patients (42.6%) died during hospital admission, 33 patients (42.9%) in the group receiving gentamicin and 7 patients in the group that did not (41.2%, P = 0.899). Worsening renal function was observed in 42 patients (54.5%) who received gentamicin and in 9 patients (52.9%) who did not (p = 0.904). Heart failure as a complication of endocarditis (OR: 4.58; CI 95%: 1.84–11.42) and not performing surgery when indicated (OR: 2.68; CI 95%: 1.03–6.94) increased mortality. Gentamicin administration remained unrelated to mortality (OR: 1.001; CI 95%: 0.29–3.38) in the multivariable analysis.

Conclusions

The addition of gentamicin to a regimen containing vancomycin or cloxacillin plus rifampicin in SPVE was not associated to better outcome.  相似文献   
110.
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