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The aquatic ecosystem is the natural habitat of microorganisms including Vibrio and Aeromonas genus which are pathogenic to human and animals. In the present investigation the frequency of these bacteria and the enzymatic characteristics of 34 Vibrio alginolyticus strains isolated from bivalves harvested in Venice Lagoon (Italy) and Guanabara Bay (Brazil) were carried out from November 2003 to February 2004. The mussels' samples were submitted to enrichment in Alkaline Peptone Water (APW) added with 1% of sodium chloride (NaCl) and APW plus 3% NaCl incubated at 37 degrees C for 18-24 h. Following the samples were streaked onto TCBS Agar (Thiossulfate Citrate Bile Sucrose Agar) and the suspected colonies were submitted to biochemical characterization. Also, the Vibrio alginolyticus strains were evaluated to collagenase, elastase and chondroitinase production. The results showed the isolation of 127 microorganisms distributed as follows: 105 Vibrio strains such as V. alginolyticus (32.4%), V. harveyi (19%) and V. parahaemolyticus (7.6%), 20 Aeromonas strains and two Plesiomonas shigelloides were the main pathogens isolated. We observed the production of the three enzymes from V. alginolyticus strains considered as the main virulence factors of the bacteria, especially in cases of human dermatological infection.  相似文献   
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Clinical Oral Investigations - Vitamin C/Ascorbic acid inhibits tyrosinase enzyme causing melanin biosynthesis suppression. This study aimed to compare the efficacy of intra-mucosal injection...  相似文献   
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Azide-bearing cell-derived extracellular matrices (“clickECMs”) have emerged as a highly exciting new class of biomaterials. They conserve substantial characteristics of the natural extracellular matrix (ECM) and offer simultaneously small abiotic functional groups that enable bioorthogonal bioconjugation reactions. Despite their attractiveness, investigation of their biomolecular composition is very challenging due to the insoluble and highly complex nature of cell-derived matrices (CDMs). Yet, thorough qualitative and quantitative analysis of the overall material composition, organisation, localisation, and distribution of typical ECM-specific biomolecules is essential for consistent advancement of CDMs and the understanding of the prospective functions of the developed biomaterial. In this study, we evaluated frequently used methods for the analysis of complex CDMs. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and (immune)histochemical staining methods in combination with several microscopic techniques were found to be highly eligible. Commercially available colorimetric protein assays turned out to deliver inaccurate information on CDMs. In contrast, we determined the nitrogen content of CDMs by elementary analysis and converted it into total protein content using conversion factors which were calculated from matching amino acid compositions. The amount of insoluble collagens was assessed based on the hydroxyproline content. The Sircol™ assay was identified as a suitable method to quantify soluble collagens while the Blyscan™ assay was found to be well-suited for the quantification of sulphated glycosaminoglycans (sGAGs). Eventually, we propose a series of suitable methods to reliably characterise the biomolecular composition of fibroblast-derived clickECM.

Common characterisation methods for cell-derived extracellular matrices (ECMs) are compared using both unmodified and azide-bearing fibroblast-derived ECM.  相似文献   
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Background and study aims

Central nervous system (CNS) involvement in hepatitis C virus (HCV) infection has different facets such as anxiety, depression, cognitive impairment and vasculitis. We were interested in detecting subclinical CNS involvement in chronic HCV infected subjects with and without systemic vasculitis.

Patients and methods

Nineteen patients (15 females and 4 males) with chronic HCV infection (mean age 46.5?±?7 and mean duration since diagnosis of HCV infection 4.7?±?4?years, including 6 (32%) Child-Pugh class A cirrhotic patients) and 30 age, sex and education matched healthy control subjects were studied. Thirteen patients had associated vasculitis. Patients and control subjects were assessed using the block design and comprehension subtests of Wechsler Bellevue Adult Intelligence Scale, Wechsler Memory scale (WMS), Beck Anxiety Inventory (BAI) and Beck Depression Inventory (BDI). Brain HMPAO Single Photon Emission Computed Tomography (SPECT) was performed for HCV patients.

Results

Patients with HCV had lower scores on the block design test compared to control subjects (8.37?±?1.89 versus 10.37?±?1.47, p?<?0.001), lower total WMS scores (43.15?±?10.49 versus 60.27?±?8.08, p?<?0.001) and higher anxiety and depression scores (16.94?±?10.46 and 37.17?±?10.38 versus 10.3?±?4.67 and 28.9?±?5.99, p?=?0.004 and 0.001, respectively). Total WMS were lower in HCV patients with vasculitis compared to those without vasculitis (39.14?±?9.3 versus 51.17?±?8.3, p?=?0.019) while the block design and comprehension tests, BAI and BDI were not significantly different between both groups. The block design and comprehension tests, WMS, BAI and BDI were not significantly different between cirrhotic and non-cirrhotic patients. Seven patients had different patterns of cerebral hypoperfusion on SPECT, and all of them had associated vasculitis. Abnormal SPECT was associated with lower total WMS scores (35.87?±?10.8 versus 46.79?±?8.6 in those with normal SPECT, p?=?0.049).

Conclusions

Vasculitis may contribute to the development of neuropsychiatric involvement in HCV patients.  相似文献   
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The COVID-19 Pandemic has put enormous pressure on the healthcare system globally, causing many healthcare organizations all over the world to cancel or stop elective procedures in their cardiac catheterization laboratoires. This delay in elective procedures with no doubt has led to a suspension of patient care primarily to those with severe aortic stenosis, which might place them at higher risk for cardiovascular complications like sudden death and heart failure.Health Care Worker are faced with the uncertainty of contracting infections while performing procedures in patients with a confirmed diagnosis of COVID-19 or suspected cases. This unprecedented situation is very challenging for the safety of Health Care Worker. Hence, in this article, we aim to summarize some of the current guidelines as to how to triage patients in need for Trans Catheter Aortic Valve Implantation (TAVI), during this ongoing pandemic, and will address some necessary considerations related to the preparation of catheterization laboratories and personal during the COVID-19 pandemic.  相似文献   
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