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41.

Background:

Chronic hepatitis B is one of the world''s major health concern. The etiological agent of this infection is hepatitis B virus (HBV), which can evade the immune system response. Transforming growth factor beta 1 (TGF-β1) can act against HBV by suppressing the viral replication. The TGF-β1 also plays an important role in preventing liver damage in chronically HBV infected patients.

Objectives:

In this study, the association of TGF-β1 +915G/C and -509C/T gene polymorphisms with chronic hepatitis B was evaluated in Iranian patients.

Materials and Methods:

A population-based case–control study was conducted in Taleghani Hospital, Tehran. A number of 220 patients with chronic hepatitis B and the same number of healthy control subjects were designated the case and the control groups. The PCR-Restriction Fragment Length Polymorphism Method (PCR-RFLP) method was used for genotyping both polymorphisms. Ten percent of the control samples were sequenced to confirm the results.

Results:

No statically significant differences in genotype distribution and allele frequency were observed for both polymorphisms between healthy controls and patients with chronic hepatitis B.

Conclusions:

There was no association between TGF-β1 -509C/T and +915G/C polymorphisms with chronic hepatitis B and it seems that these changes don not play a significant role in increasing the risk of chronic infection in Iranian patients.  相似文献   
42.

Background:

Occult hepatitis C virus infection (OCI) is recognized by finding hepatitis C virus (HCV) RNA in hepatocytes without detectable anti-HCV antibodies and viral RNA in plasma. Autoimmune hepatitis (AIH) is a chronic and generally progressive disease without exactly-identified etiology.

Objectives:

This study aimed to determine the prevalence of OCI among patients with AIH and to evaluate the tests used to rule out HCV infection in diagnosing AIH.

Patients and Methods:

Between July 2012 to February 2013, 35 Iranian patients with AIH who attended Tehran Hepatitis Center were investigated. For identifying OCI, detection of HCV RNA in both ultracentrifuged serum samples and peripheral blood mononuclear cells (PBMCs) was used. Data analysis was performed using SPSS.

Results:

Six males and 29 females with mean disease duration of 77.1 ± 39.5 month and mean age of 43.62 ± 12.67 years were investigated. All cases were negative for anti-HCV antibody and we could not find any HCV RNA in ultracentrifuged serum samples and PBMCs.

Conclusions:

With our laboratory diagnostic method, it seems that there are no cases of OCI in patients with AIH. However, we recommend further studies with more samples and more precise laboratory method.  相似文献   
43.
The macrocyclic ligand calix[4]arene (L1) and its sulphur-containing analogue thia[4]calixarene (L2) are promising precursors for functional molecular materials as they offer rational functionalization with various organic groups. Here, we present the first example of lanthanide-based coordination polymers built from the macrocyclic thiacalix[4]arene backbone bearing four carboxylic moieties, namely, ligand H4L3. The combination of H4L3 with the Tb3+ and Dy3+ cations led to the formation of 1D ladder-type coordination polymers with the formula [LnIIIHL3DMF3]·(DMF) (where DMF = dimethylformamide and Ln = Tb or Dy, denoted as HL3–Tb and HL3–Dy), which resulted from the coordination of the lanthanide cations with the partially deprotonated ligand HL33− that behaved as a T-shape connector. The coordination sphere around the metal was completed by the coordinated DMF solvent molecules. By combining both Tb3+ and Dy3+ cations, isostructural heterobimetallic solid solutions HL3–Tb1−xDyx were also prepared. HL3–Tb and HL3–Dy showed visible light photoluminescence originating from the f–f electronic transitions of pale green emissive Tb3+ and pale yellow emissive Dy3+ with efficient sensitization by the functionalized thia[4]calixarene ligand HL3. In the HL3–Tb1−xDyx solid solutions, the Tb/Dy ratio governed both the emission colour as well as the emission quantum yield, which reached even 28% at room temperature for HL3–Tb. Moreover, HL3–Dy exhibited a slow magnetic relaxation effect related to the magnetic anisotropy of the dodecahedral Dy3+ complexes, which were well isolated in the crystal lattice by expanded organic spacers.

The single crystals of the two isostructural Tb3+- and Dy3+-based coordination polymers (HL3–Tb and HL3–Dy) were structurally characterized, and their photophysical properties were investigated, together with their corresponding solid solutions.  相似文献   
44.
Background: One of the most challenging problems in clinical surgery is management of an extensive duodenal injury. In its management, there are limitations in using jejunal serosal patch and other conventional methods in specific conditions. This study was performed to compare treatment of large duodenal defects by a gallbladder serosal patch and the gallbladder mucosal patch in a dog as an animal model. Methods: A duodenal defect (2 cm, about 50% of the total circumference) was created in the second portion of the duodenum in eight dogs. The animals were divided into two equal groups, with group 1 undergoing serosal patch repair and group 2 undergoing mucosal patch repair. The macroscopic and microscopic healing features of the gallbladder serosal and mucosal patch were compared. Results: None of the dogs died due to surgical complications. The whole grafted area was covered by neomucosa at the end of the third week in all animals with the gallbladder serosal patch (group 1). In this group, the scar was small; no significant narrowing of lumen was noted and serosal healing was uniformly complete. In histological examination, a complete coverage of the gallbladder serosal patch by neomucosa consisting of columnar epithelium with short villous formations was observed. In mucosal patch models (group 2), complete epitheliazation, mild fibrosis, and incomplete repair were visible. In histological examination, severe inflammation was noticed too. Conclusion: In patients with multiple trauma affecting upper gastrointestinal tracts, use of the gallbladder serosal patch method is easy and reliable. So it may be considered in the surgical management of large duodenal defects, which cannot be repaired by available conventional methods.  相似文献   
45.
Neurological Sciences - The prevalence of osteoporosis is reported differently. We designed this systematic review and meta-analysis to estimate pooled prevalence of osteoporosis and osteopenia in...  相似文献   
46.
In the stromal keratitis caused by herpes simplex virus (HSV), the formation of new vessels is the essential step for the pathogenesis of keratitis. Inhibition of angiogenesis diminishes the formation of corneal lesion induced by HSV. Procedures which suppress angiogenesis are proposed as a valuable therapeutic approach to control HSK. The mechanism by which HSV ocular infection results in corneal angiogenesis is not understood. Recent reports identified anti-vascular endothelial growth factor (VEGF) as a molecule that is highly expressed in the HSV infected eye and clearly involved in angiogenesis. The advent of VEGF treatments marks a major advancement in the treatment of angiogenic eye disease. Off-label use of bevacizumab (Avastin), a recombinant humanized monoclonal antibody directed against VEGF, in some neovascular disorders of the eye has been associated with promising short term results. Based on these evidences herein we hypothesize topical application of bevacizumab could inhibit corneal neovascularization and also scarring in HSK. We propose this drug as a novel adjunct to current anti-inflammatory strategies in HSK.  相似文献   
47.
48.
Brain Imaging and Behavior - A higher incidence of cognitive impairment (CI) has previously been reported among orchiectomized testicular cancer patients (TCPs), but little is known about the...  相似文献   
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