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241.

Background:

The hepatitis B virus is an important healthcare problem. According to current clinical practice, a liver biopsy is required for the diagnosis and treatment of chronic liver disease. However, a liver biopsy is an invasive, inconvenient procedure, which requires an expert pathologist opinion. Therefore requirement of biochemical tests, which are considered to indicate hepatic fibrosis and may be repeated easily, increases gradually today.

Objectives:

This study evaluated the correlation between hepatic fibrosis and routine laboratory values in patients with chronic hepatitis B.

Patients and Methods:

The files of 456 patients with CHB (chronic hepatitis B) who were referred to the infectious diseases and clinical microbiology clinic between January 2009 and March 2012 were screened retrospectively. Liver biopsy samples were examined according to Ishak scoring. Laboratory parameters and histopathology reports were recorded, and correlations between the fibrosis grade and laboratory parameters were analyzed.

Results:

There were 320 male and 136 female patients, with a mean age 36.7 ± 12.1 years. According to liver biopsy results, a low fibrosis score (stage 0-2) was detected in 281 patients (61.6%), and a high fibrosis score (stage 3-5) was detected in 175 patients (38.4%). Patients with a high fibrosis score had significantly higher ALT (alanine amino transferase), AST (aspartate aminotransferase), and HBV-DNA values and a significantly lower platelet count compared with those with a low fibrosis score (P = 0.001, 0.001, 0.025, and 0.001, respectively). A positive correlation was detected between the fibrosis score and age, BMI, HAI, ALT, and AST values, and a negative correlation was detected between the fibrosis score and albumin and platelet counts. In the regression analysis performed to evaluate the factors associated with high-stage fibrosis, fibrosis was determined to be associated with thrombosis, ALT, and gender. The results of the regression analysis demonstrated that the risk of fibrosis was 4.6 fold higher in men.

Conclusions:

According to the results obtained in our study, advanced age, higher BMI, AST, ALT, and HBV-DNA levels, and low albumin and platelet levels are correlated with advanced fibrosis in patients with CHB.  相似文献   
242.

Background:

Rate of coinfection with human immunodeficiency virus (HIV) and hepatitis C virus (HCV) varies in different countries. This may be attributable to common transmission routes as well as social, economic, and cultural factors.

Objectives:

The purpose of this study was to investigate the prevalence and risk factors of HCV infection among HIV-positive patients in Istanbul, Turkey.

Patients and Methods:

Since January 2006 to November 2013, 949 HIV-positive patients that were enrolled in this study by ACTHIV-IST (Action Against HIV in Istanbul) Study Group, which consists of five centers to follow up HIV-positive patients in Istanbul. Epidemiologic and clinical data were collected retrospectively from medical records and were transferred to an HIV database system.

Results:

Among 949 patients, 84% were men and the mean age was 37.92 ± 11.54 years (range, 17-79). The most frequent route of transmission was heterosexual intercourse (48.8%), followed by men having sex with men (30.5%). Only nine patients (0.9%) had history of injection drug use (IDU). The prevalence of HIV/HCV coinfection was 0.9% (9:949). The IDU rate was 44.4% (4:9) in patients with HIV/HCV coinfection (three of them were not Turkish citizens), whereas this rate was only 0.6% (5:881) in patients with only HIV infection (P < 0.01). Genotypes 1b, 2a/2c, and 3 were determined in five, one, and two patients, respectively. Genotype could not be determined in one patient. History of residence in a foreign country (P < 0.01) and imprisonment (P < 0.01) were also considered as risk factors in terms of HIV/HCV coinfection.

Conclusions:

Prevalence of HIV/HCV coinfection is considerably low in Turkey. The extremely rare prevalence of IDU might have a role in this low prevalence.  相似文献   
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Background: The exact etiology of irritable bowel syndrome (IBS) remains unclear. Curative treatment is not available and current treatment modalities are mainly directed against the predominant symptoms. There are a few studies reporting the beneficial effects of transcutaneous electrical stimulation in patients with chronic constipation, gastroparesis, and functional dyspepsia. Aim: To investigate whether transcutaneous electrical stimulation is an effective procedure in IBS patients. Methods: IBS patients were randomly placed in vacuum interferential current (IFC) and placebo groups. Both treatments consisted of 12 sessions administered over 4 weeks. Symptoms due to IBS were documented via questionnaires, including the IBS Global Assessment of Improvement Scale, numeric rating scales, visual analogue scale, and IBS Quality of Life Scale at the beginning of, end of, and 1 month after the treatment. Results: Patients in the therapy (29 cases) and placebo (29 cases) groups were homogeneous with respect to demographic data and gastrointestinal system symptoms. When compared to the beginning scores, severity of abdominal discomfort, bloating, and abdominal distension and rumbling improved significantly in either interference or placebo groups at both the end of treatment and 1 month after treatment. In the IFC group, severity of symptoms continued to decrease significantly at 1 month after treatment when compared to scores at just the end of treatment, whereas in the placebo group severity of these symptoms did not change significantly on numeric severity scales. Also, the visual analogue scale of the first month after treatment continued to decrease significantly when compared to the level at the end of treatment in the IFC group. Total quality score increased significantly in the IFC group. Conclusions: Vacuum IFC therapy can significantly improve symptoms and quality of life in patients with IBS. It may represent a novel treatment modality for drug-refractory IBS patients.  相似文献   
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Spontaneous degradation of bottlebrush macromolecules on aqueous substrates was monitored by atomic force microscopy. Scission of C─C covalent bonds in the brush backbone occurred due to steric repulsion between the adsorbed side chains, which generated bond tension on the order of several nano-Newtons. Unlike conventional chemical reactions, the rate of bond scission was shown to decrease with temperature. This apparent anti-Arrhenius behavior was caused by a decrease in the surface energy of the underlying substrate upon heating, which results in a corresponding decrease of bond tension in the adsorbed macromolecules. Even though the tension dropped minimally from 2.16 to 1.89 nN, this was sufficient to overpower the increase in the thermal energy (kBT) in the Arrhenius equation. The rate constant of the bond-scission reaction was measured as a function of temperature and surface energy. Fitting the experimental data by a perturbed Morse potential V = V0(1 - e-βx)2 - fx, we determined the depth and width of the potential to be V0 = 141 ± 19 kJ/mol and β-1 = 0.18 ± 0.03 , respectively. Whereas the V0 value is in reasonable agreement with the activation energy Ea = 80–220 kJ/mol of mechanical and thermal degradation of organic polymers, it is significantly lower than the dissociation energy of a C─C bond De = 350 kJ/mol. Moreover, the force constant Kx = 2β2V0 = 1.45 ± 0.36 kN/m of a strained bottlebrush along its backbone is markedly larger than the force constant of a C─C bond Kl = 0.44 kN/m, which is attributed to additional stiffness due to deformation of the side chains.  相似文献   
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