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991.
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993.
BackgroundVaginal stenosis (VS) is a common side effect of pelvic radiotherapy for gynecological cancer in women. It has a high incidence variability, likely due to unstandardized and subjective assessment methods. Furthermore, even though the worldwide standard treatment for VS is vaginal dilation, low compliance rates have been noted.AimTo evaluate the parameters used to diagnose VS and to assess whether the lack of an objective measure of VS hampers vaginal dilator use.MethodsA systematic review in accordance with the PRISMA reporting guidelines was conducted. PubMed, EMBASE, and Web of Science databases were searched. Randomized trials and prospective, retrospective, and cross-sectional studies published from January 2011 to February 2020 were included.OutcomesThe main outcome of this study was a review of the published literature on assessment methods for VS and compliance to vaginal dilator use.ResultsOf the 28 articles obtained, only 7 used objective methods to measure the vaginal volume. 3 studies have demonstrated patient's concern with VS development and showed a high compliance to dilator use, whereas others reported several barriers to dilator use.Clinical ImplicationsLack of an objective assessment method can be a predisposing factor for uncertain VS incidence rates and impair compliance to vaginal dilator therapy, leading to long-term VS and sexual dysfunction.Strengths & LimitationsThis is the first systematic review on the heterogeneity of VS evaluation methods and compliance to vaginal dilator use. All studies were comprehensively evaluated by 2 reviewers. The limitations included the heterogeneity of the study designs and the unstandardized criteria used to classify stenosis or to evaluate compliance to dilator use. Although 3 well-known databases were used, the inclusion of more data sources could have increased the number of publications included in this review.ConclusionVS is frequently diagnosed using subjective parameters. Few unstandardized objective methods are used to evaluate this condition. Regarding compliance to vaginal dilator use, there was a high dropout rate during follow-up and no consensus on starting time or ideal usage.Haddad NC, Soares Brollo LC, Pinho Oliveira MA, et al. Diagnostic Methods for Vaginal Stenosis and Compliance to Vaginal Dilator Use: A Systematic Review. J Sex Med 2021;18:493–514.  相似文献   
994.
Hepatitis C virus (HCV) is a frequent cause of acute and chronic hepatitis and a leading cause for cirrhosis of the liver and hepatocellular carcinoma. HCV is classified in six major genotypes and more than 70 subtypes. In Colombian blood banks, serum samples were tested for anti‐HCV antibodies using a third‐generation ELISA. The aim of this study was to characterize the viral sequences in plasma of 184 volunteer blood donors who attended the “Banco Nacional de Sangre de la Cruz Roja Colombiana,” Bogotá, Colombia. Three different HCV genomic regions were amplified by nested PCR. The first of these was a segment of 180 bp of the 5′UTR region to confirm the previous diagnosis by ELISA. From those that were positive to the 5′UTR region, two further segments were amplified for genotyping and subtyping by phylogenetic analysis: a segment of 380 bp from the NS5B region; and a segment of 391 bp from the E1 region. The distribution of HCV subtypes was: 1b (82.8%), 1a (5.7%), 2a (5.7%), 2b (2.8%), and 3a (2.8%). By applying Bayesian Markov chain Monte Carlo simulation, it was estimated that HCV‐1b was introduced into Bogotá around 1950. Also, this subtype spread at an exponential rate between about 1970 to about 1990, after which transmission of HCV was reduced by anti‐HCV testing of this population. Among Colombian blood donors, HCV genotype 1b is the most frequent genotype, especially in large urban conglomerates such as Bogotá, as is the case in other South American countries. J. Med. Virol. 82:1889–1898, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
995.
The aim of this work was to develop novel electrospun nanofiber meshes coated with a biomimetic calcium phosphate (BCP) layer that mimics the extracellular microenvironment found in the human bone structure. Poly (epsilon-caprolactone) (PCL) was selected because of its well-known medical applications, its biodegradability, biocompatibility and its susceptibility to partial hydrolysis by a straightforward alkaline treatment. The deposition of a calcium phosphate layer, similar to the inorganic phase of bone, on PCL nanofiber meshes was achieved by means of a surface modification. This initial surface modification was followed by treatment with solutions containing calcium and phosphate ions. The process was finished by a posterior immersion in a simulated body fluid (SBF) with nearly 1.5 x the inorganic concentration of the human blood plasma ions. After some optimization work, the best conditions were chosen to perform the biological assays. The influence of the bone-like BCP layer on the viability and adhesion, as well as on the proliferation of human osteoblast-like cells, was assessed. It was shown that PCL nanofiber meshes coated with a BCP layer support and enhance the proliferation of osteoblasts for long culture periods. The attractive properties of the coated structures produced in the present work demonstrated that those materials have potential to be used for applications in bone tissue engineering. This is the first time that nanofiber meshes could be coated with a biomimetic bone-like calcium phosphate layer produced in a way that the original mesh architecture can be fully maintained.  相似文献   
996.
BACKGROUND: Mite allergens have been involved in airway sensitization and allergic diseases. Immunoassays for the identification and quantifiction of house dust mite (HDM) allergens are useful to improve the knowledge of regional mite fauna and the remediation of mite allergens in allergic diseases. The present study analyzed the association between levels of HDM allergen and results of mite identification or skin prick test (SPT) in two different areas of Bahia, Brazil. METHODS: Forty-two asthmatic subjects from a rural area (group I; n = 21) and a slum (group II; n = 21) were evaluated through SPT with HDM allergens and had dust samples collected at their homes for mite identification and allergen measurements. RESULTS: Positive SPT to Dermatophagoides pteronyssinus, Dermatophagoides farinae and Blomia tropicalis allergens were observed in 42.9, 38.0 and 42.9% subjects from group I and in 47.6, 19.0 and 33.3% subjects from group II, respectively. D. pteronyssinus and B. tropicalis were identified in approximately 76 and 50% of samples from both groups, respectively. D. farinae was identified in 38.0 and 9.5% of samples from groups I and II, respectively (p < 0.005). Der p 1, Der f 1 and Blo t 5 detection were associated with mite identification (p < 0.05). Association between HDM allergen levels over 2 microg/g of dust and positive SPT occurred only with D. pteronyssinus (p < 0.0001). CONCLUSIONS: D. pteronyssinus was the most prevalent mite species in this study followed by B. tropicalis and D. farinae. Immunoassays done to measure mite allergens were associated with mite-species identification. We conclude that these three mite species must be included on panels for the diagnosis of allergic airway diseases in subjects living in such regions.  相似文献   
997.
Leishmania (Viannia) braziliensis is the major causative agent of American tegumentary leishmaniasis, a disease that has a wide geographical distribution and is a severe public health problem. The cysteine proteinase B (CPB) from Leishmania spp. represents an important virulence factor. In this study, we characterized and localized cysteine proteinases in L. (V.) braziliensis promastigotes. By a combination of triton X-114 extraction, concanavalin A-affinity, and ion exchange chromatographies, we obtained an enriched fraction of hydrophobic proteins rich in mannose residues. This fraction contained two proteinases of 63 and 43 kDa, which were recognized by a CPB antiserum, and were partially sensitive to E-64 in enzymatic assays with the peptide Glu-Phe-Leu. In confocal microscopy, the CPB homologues localized in the peripheral region of the parasite. This data together with direct agglutination and flow cytometry assays suggest a surface localization of the CPB homologues. The incubation of intact promastigotes with phospholipase C reduced the number of CPB-positive cells, while anti-cross-reacting determinant and anti-CPB antisera recognized two polypeptides (63 and 43 kDa) derived from phospholipase C treatment, suggesting that some CPB isoforms may be glycosylphosphatidylinositol-anchored. Collectively, our results suggest the presence of CPB homologues in L. braziliensis surface and highlight the need for further studies on L. braziliensis cysteine proteinases, which require enrichment methods for enzymatic detection.  相似文献   
998.
The atypical chemokine receptor D6 is a decoy and scavenger receptor for most inflammatory CC chemokines and prevents the development of exacerbated inflammatory reactions. Here we report that mice lacking D6 expression in the nonhematopoietic compartment have a selective increase in the number of Ly6C(high) monocytes in the circulation and in secondary lymphoid tissues. Under inflammatory conditions, Ly6C(high) monocytes accumulate in increased number in secondary lymphoid organs of D6(-/-) mice in a CCR2-dependent manner. Ly6C(high) monocytes derived from D6(-/-) mice have enhanced immunosuppressive activity, inhibit the development of adaptive immune responses, and partially protect mice from the development of GVHD. Thus, control of CCR2 ligands by D6 regulates the traffic of Ly6C(high) monocytes and controls their immunosuppressive potential.  相似文献   
999.
Hypertension is a major public health problem due to its high prevalence andcardiovascular complications. Its treatment is aimed at reducing cardiovascularmorbidity and mortality, its goal being to maintain blood pressure levels below140/90 mm Hg. Hypertension control in Brazil is low, and nationwide rates areunknown. The objective of this review was to provide an overview on hypertensioncontrol in Brazil from publications in a database. We identified 45 publications. Inpopulation-based studies, the highest control rate (57.6%) was reported in amulticenter study in 100 municipalities and the city of São José do RioPreto, São Paulo state (52.4%), while the lowest rates (around 10%) wereidentified in microregions of the Rio Grande do Sul state and in the city ofTubarão, Santa Catarina state. In conclusion, the studies assessed showed awide variation in hypertension control rates. It is worth noting that the comparisonbetween studies was a major limiting factor, because of the different methodsused.  相似文献   
1000.
Pancreatic acinar cells accumulate amino acids against a marked concentration gradient to synthesize digestive enzymes. Thus, the function of acinar cells depends on amino acid uptake mediated by active transport. Despite the importance of this process, pancreatic amino acid transporter expression and cellular localization is still unclear. We screened mouse pancreas for the expression of genes encoding amino acid transporters. We showed that the most highly expressed transporters, namely sodium dependent SNAT3 (Slc38a3) and SNAT5 (Slc38a5) and sodium independent neutral amino acids transporters LAT1 (Slc7a5) and LAT2 (Slc7a8), are expressed in the basolateral membrane of acinar cells. SNAT3 and SNAT5, LAT1 and LAT2 are expressed in acinar cells. Additional evidence that these transporters are expressed in mature acinar cells was gained using acinar cell culture and acute pancreatitis models. In the acute phase of pancreatic injury, when acinar cell loss occurs, and in an acinar cell culture model, which mimics changes occurring during pancreatitis, SNAT3 and SNAT5 are strongly down-regulated. LAT1 and LAT2 were down-regulated only in the in vitro model. At protein level, SNAT3 and SNAT5 expression was also reduced during pancreatitis. Expression of other amino acid transporters was also modified in both models of pancreatitis. The subset of transporters with differential expression patterns during acute pancreatitis might be involved in the injury/regeneration phases. Further expression, localization and functional studies will follow to better understand changes occurring during acute pancreatitis. These findings provide insight into pancreatic amino acid transport in healthy pancreas and during acute pancreatitis injury.  相似文献   
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