Collagen V α1 Chain Decrease in Papillary Dermis from Early Systemic Sclerosis: A New Proposal in Cutaneous Fibrosis Molecular Structure.

Cutaneous fibrosis is one of the main features of systemic sclerosis (SSc). Recent findings correlated abnormal collagen V (Col V) deposition in dermis with skin thickening and disease activity in SSc. Considering that Col V is an important regulator of collagen fibrillogenesis, understanding the role of Col V in the first two years of the skin fibrosis in SSc (early SSc) can help to determine new targets for future treatments. In this study, we analyzed the morphological, ultrastructural and molecular features of α1(V) and α2(V) chains and the expression of their coding genes COL5A1 and COL5A2 in collagen fibrillogenesis in early-SSc. Skin biopsies were obtained from seven consecutive treatment-naïve patients with SSc-related fibrosis and four healthy controls. Our data showed increased α1(V) and α2(V) chain expression in the reticular dermis of early-SSc patients; however, immunofluorescence and ultrastructural immunogold staining determined a significant decreased expression of the α1(V) chain along the dermoepidermal junction in the papillary dermis from early-SSc-patients in relation to the control (12.77 ± 1.34 vs. 66.84 ± 3.36; p < 0.0001). The immunoblot confirmed the decreased expression of the α1(V) chain by the cutaneous fibroblasts of early-SSc, despite the increased COL5A1 and COL5A2 gene expression. In contrast, the α2(V) chain was overexpressed in the small vessels (63.18 ± 3.56 vs. 12.16 ± 0.81; p < 0.0001) and capillaries (60.88 ± 5.82 vs. 15.11 ± 3.80; p < 0.0001) in the reticular dermis of early-SSc patients. Furthermore, COLVA2 siRNA in SSc cutaneous fibroblasts resulted in a decreased α1(V) chain expression. These results highlight an intense decrease in the α1(V) chain along the dermoepidermal junction, suggesting an altered molecular histoarchitecture in the SSc papillary dermis, with a possible decrease in the expression of the α1(V)3 homotrimeric isoform, which could interfere with the thickening and cutaneous fibrosis related to SSc.

Microbiological identification and resistance profile of microorganisms in pressure injuries after the use of polyhexamethylene biguanide: a series of fourteen cases.

INTRODUCTION: Colonization of a pressure injury with microorganisms can negatively affect wound healing. Thus, it is necessary to evaluate which products best facilitate wound healing. OBJECTIVE: This case series evaluated the effectiveness of the antimicrobial polyhexamethylene biguanide (PHMB) on microorganisms in pressure injuries. MATERIALS AND METHODS: Fourteen patients (14 wounds) were treated with PHMB in the hospital setting after collection of a wound swab sample for microbiological analysis and determination of the risk profile using the disk diffusion method. RESULTS: Thirteen lesions (92.9%) were positive for 1 or more bacterial strains, the most prevalent of which were Staphylococcus aureus and Pseudomonas aeruginosa. Two strains of methicillin-resistant S aureus (MRSA) were also identified. Klebsiella pneumoniae demonstrated 100% resistance to the tested antibiotics, with Acinetobacter demonstrating 90% resistance, P aeruginosa 88.9%, Citrobacter freundii 87.5%, S aureus 66.7%, and MRSA 57.1%. Only Serratia marcescens demonstrated no resistance to any antibiotic tested. Polyhexamethylene biguanide was effective only against strains of S marcescens, which were not present in the second wound swab sample collected (after the application of PHMB); other microorganisms were present in the second wound swab sample collected. CONCLUSIONS: Polyhexamethylene biguanide has an immediate antimicrobial effect on S marcescens. However, it had no qualitative effect on the other microorganisms. Studies with larger populations and randomized clinical trial methodologies are necessary to elucidate additional findings concerning the effectiveness of PHMB in managing microorganisms in pressure injuries.

Caesarean section to prevent transmission of hepatitis B: a meta-analysis.

BACKGROUND: Vertical transmission of hepatitis B virus (HBV) occurs in up to 10% to 20% of births. OBJECTIVE: To assess whether Caesarean section, compared with vaginal delivery, prevents HBV transmission. METHODS: A systematic review and meta-analysis was conducted. Two investigators independently searched PubMed, EMBASE and other databases for relevant studies published between 1988 and 2013. A manual search of relevant topics and major conferences for abstracts was also conducted. Randomized trials, cohort and case-control studies assessing the effect of delivery mode on vertical transmission of HBV were included. Studies assessing antiviral therapy and patients with coinfection were excluded. The primary outcome was HBV transmission rates according to delivery method. RESULTS: Of the 430 studies identified, 10 were included. Caesarean section decreased the odds of HBV transmission by 38% compared with vaginal delivery (OR 0.62 [95% CI 0.40 to 0.98]; P=0.04) based on a random-effects model. Significant heterogeneity among studies was found (I²=63%; P=0.003), which was largely explained by variation in hepatitis B immune globulin (HBIG) administration. Meta-regression showed a significant linear association between the percentage of infants receiving HBIG per study and the log OR (P=0.005), with the least benefit observed in studies with 100% HBIG administration. Subgroup analysis of hepatitis B e-antigen-positive women who underwent Caesarean section did not show a significant reduction in vertical transmission. DISCUSSION: Caesarean section may protect against HBV transmission; however, convincing benefit could not be demonstrated due to significant study heterogeneity from variable HBIG administration, highlighting the importance of HBIG in HBV prevention. CONCLUSION: More high-quality studies are needed before any recommendations can be made.

Experimental diabetes modulates collagen remodelling of joints in rats.

UNLABELLED: The aim of this study was to evaluate extracellular matrix components in articular cartilage, ligaments and synovia in an experimental model of diabetes. Young Wistar rats were divided into a streptozotocin-induced (STZ; 35 mg/kg) diabetic group (DG; n=15) and a control group (CG; n=15). Weight, blood glucose and plasma anti-carboxymethyllysine were measured 70 days after STZ infusions. Knee joints, patellar ligaments, and lateral and medial collateral ligaments were isolated and stained with hematoxylin-eosin and Picrosirius. The total collagen content was determined by morphometry. Immunofluorescence was employed to evaluate types I, III, and V collagen in ligaments and synovial tissues and types II and XI collagen in cartilage. RESULTS: Higher blood glucose levels and plasma anti-carboxymethyllysine were observed in DG rats when compared to those in CG rats. The final weight was significantly lower in the DG rats than in the CG rats. Histomorphometric evaluation depicted a small quantity of collagen fibers in ligaments and articular cartilage in DG rats, as well as increased collagen in synovial tissue. There was a decrease in cartilage proteoglycans in DG rats when compared with CG rats. Immunofluorescence staining revealed an increase of collagen III and V in ligaments, collagen XI in cartilage, and collagen I in synovial tissue of DG rats compared with CG rats. CONCLUSION: The ligaments, cartilage and synovia are highly affected following STZ-induced diabetes in rats, due the remodeling of collagen types in these tissues. This process may promote the degradation of the extracellular matrix, thus compromising joint function. Our data may help to better understand the pathogenesis of joint involvement related to diabetes.

Eficácia do hCG em baixa dose para completar a estimulação ovariana iniciada com FSH recombinante / Efficacy of low dose hCG alone following recombinant FSH for controlled ovarian stimulation

O objetivo da presente comunicação é o de relatar os resultados de ciclos de FIV/ICSI com o emprego de FSH recombinante (r-FSH) durante todo o ciclo de estimulação e o uso de baixa dose de hCG isoladamente para completar a estimulação iniciada com r-FSH.