FUNCTIONAL HETEROGENEITY OF FIBROBLASTS IN DERMAL WOUND HEALING

Impaired wound healing can lead to excessive scarring, dehiscence, chronic ulcers, and infection, which have adverse impact on the quality of life and pose a significant economic burden on the health care system. Thus, new therapeutic approaches are critically important. Dermal fibroblasts are critical players in cutaneous wound healing, possibly lending their contractile properties and extracellular matrix (ECM) remodeling functions to promote effective tissue repair. Dermal fibroblasts are also postulated to orchestrate tissue repair by interacting with and controlling other cell types in the wound microenvironment. It has become increasingly clear that the generic term “fibroblast” encompasses a diverse cell population with distinct origins and heterogeneous functions. Fibroblast heterogeneity is in part exemplified by the numerous expression markers used to distinguish them. The overarching goal of this study is to precisely define the heterogeneity of dermal fibroblasts and unravel their functional roles during cutaneous wound healing process. In order to decipher the dynamics of fibroblast marker composition during the wound repair process we utilized multiplexed immunolabeling platforms in order to quantify the expression of multiple fibroblast markers within a single tissue. Using this approach, along with lineage tracing studies, we observed that a population of resident dermal fibroblasts in normal skin, labeled with FSP1/S100A4, acquire the myofibroblast phenotype associated with acquisition of ⍺SMA expression. Importantly, not all ⍺SMA+ cells arose from FSP1/S100A4+ progenitors, indicating that there exist at least two populations of fibroblasts which contribute to the pool of activated myofibroblasts during tissue repair. Further experimentation was carried using transgenic mouse models which allow selective depletion based on expression of fibroblast markers such as ⍺SMA, FSP1/S100A4, FAP, and Collagen1⍺1. Using these models, we were able to identify unique phenotypes associated with depletion of these populations in the context of wound repair. While depletion of ⍺SMA+ cells resulted in a complete inability to re-epithelialize, results from other depletion models were more nuanced, affecting collagen deposition, revascularization, and dermal thickness. The work presented here offers novel insights on the dynamic nature of wound healing fibroblasts and proposes new avenues for the treatment of chronic wounds

Recurrent Henoch-Schönlein purpura in familial mediterranean fever

Familial Mediterranean fever (FMF) is a relatively rare disorder, characterized by recurrent self-limited attacks of fever and polyserositis. Diagnosis is made by clinical features, gene identification on chromosome 16 and clinical response to specific treatment. Different types of vasculitis have been reported in FMF. Henoch-Schönlein purpura (HSP) is one of them, usually with a benign clinical course. Repeated attacks of HSP have been rarely reported in FMF. This is the report of a 7-year-old girl who presented initially with recurrent fever and abdominal pain. After the primary diagnosis of FMF and appropriate treatment, she experienced two documented repeated attacks of HSP with severe renal involvement (crescentic glomerulonephritis) and protracted abdominal pain in the second one. Glomerulonephritis was controlled by methyl-prednisolone pulse therapy plus oral corticosteroid and azathioprine, but abdominal pain was resistant to steroids and revealed completely by intravenous immunoglobulin (IVIg) administration. In conclusion, it is suggested to consider the recurrence of HSP in cases with FMF to prevent irreversible renal complications. IVIg seems to be a good choice for the management of intractable abdominal pain of HSP. © 2008 Tehran University of Medical Sciences. All rights reserved

Correlation of sacral ratio and urinary tract infection in children

Introduction: The sacral bone anomalies have an important effect on urinary and gastrointestinal tract and sacral ratio was defined as an indicator for estimating the anorectal abnormalities in children. This study was carried out for determining the association between sacral ratio and Urinary Tract Infections (UTI) among children. Material and Methods: In a cross sectional study, 100 children under 15 years with proven febrile UTI were referred to a referral children center considering the presence and grading of VUR according to VCUG enrolled in this study. Sacral ratio was measured for all cases and the data were compared by student T test, Chi 2 and Mann Whitney tests. SPSS 16.0 software was used for data analysis. P values less than 0.05 were considered significant. Results: 41 boys and 59 girls with mean age 4.8 years were enrolled in this study. The average range of sacral ratio was 0.82. There was no staistical difference between two different genders and ages (p > 0.05). The values of SR in patients with VUR were lower than patients without VUR(P�0.05) but there was no statistically significant difference between both bilateral and unilateral VUR and SR (p > 0.05). Conclusion: The risk of sacral bone abnormality in patients with VUR is more than patients without VUR. Therefore, in patients with UTI and low SR simultaneously, tighter evaluation for VUR and treatment should be considered. © 2018 Kandarini et al

Serum magnesium levels in neonatal jaundice: Is there any correlation between hypermagnesemia and moderate to severe hyperbilirubinemia in term newborns?

Background: Neonatal jaundice is a common major problem; on the other hand, it is suggested that there is a correlation between plasma magnesium concentrations and hyperbilirubinemia during the neonatal period. Objectives: The study aims to validate a previously reported risk index for predicting the magnesium level of plasma for moderate to severe hyperbilirubinemia in infant neonates. Methods: A cross-sectional correlation study was performed on 93 term newborns with indirect hyperbilirubinemia admitted in neonatology unit of a children hospital and plasma magnesium level of moderate to severe Neonatal hyperbilirubinemia were determined, and statistical analysis was performed. Results: Authors did not find any statistically meaningful positive or negative correlation between plasma Mg level and bilirubin in patients studied; however, comparison of Mg level in two groups of severe and moderate hyperbilirubinemia showed decreased dispersion of medium Mg level in the severe group. Conclusions: Serum magnesium concentration is not useful in anticipation of which newborn infant will develop hyperbilirubinemia. Copyright © 2020, Journal of Comprehensive Pediatrics

Comparison of clinical findings and rapid streptococcal antigen detection test in the diagnosis of group a Streptococcal (GAS) pharyngitis

Background: Group A β-hemolytic Streptococcal (GAS) pharyngitis is a common illness in children. Diagnosis and proper treatment of group A streptococcal sore throat is important particularly to prevent non-superlative sequel. Clinical findings continue to be used in differentiating streptococcal infection from viral sore throat. Objectives: The aim of this study was to evaluate the accuracy of clinical findings and rapid test in comparison with culture in the diagnosis of group A Streptococcal (GAS) pharyngitis. Patients and Methods: Ninety-four children between 3 to 16 years, who were referred to the pediatric clinic of Rasoul-e-Akram hospital with clinical findings of fever or sore throat were evaluated from October 2006 to May 2007. Clinical findings were recorded and swabs were taken for group A streptococcal cultures and streptococcal rapid antigen detection test. Analysis of statistical significance was performed using the chi-square method. The accuracy of clinical findings and rapid test was compared with the culture method as the gold standard, and sensitivity, specificity, positive predictive values, negative predictive value, positive likelihood ratio (LR+) and negative likelihood ratio (LR-) were calculated. Results: The culture was positive in 38 (40.4) of the 94 evaluated children. The mean age of children was 8 ± 3.7 years. The presence of petechiae, exudate and Lymphadenopathy (LAP) was more likely in children with positive streptococcus culture and rapid test (P value < 0.05). Lymphadenopathy was known to feature the most sensitivity (100), specificity (76.8), and positive predictive value (74.5), negative predictive value (100) and positive likelihood ratio (LR) (4.3) among clinical findings. The results of rapid test showed sensitivity of 89.4, specificity of 100, positive predictive value of 100, and negative predictive value of 93.3 in comparison with culture as the gold standard. In general, the accuracy of rapid test was found higher than subjective clinical findings (P = 0.001) Conclusions: Although LAP had good performance in early diagnosis of GAS, a combination of clinical findings, including tonsillar exudates, petechiae with results of rapid antigen test or culture is necessary for clinician judgment. Throat culture is the gold standard test for detecting group A Streptococcal infection, but rapid test is a good replacement for culture. © 2016, Infectious Diseases and Tropical Medicine Research Center

Seroepidemiology of Varicella and value of self-reported history of Varicella infection in Iranian medical students

Objectives: We conducted this study to assess the seroprevalence of Varicella zoster virus (VZV) antibodies in a group of Iranian medical sciences students that were at risk of Varicella and the value of self-reported history as a predictor of immunity. Material and Methods: 255 medical, nursing and obstetrics students who had not entered as a student or worked in a hospital from 3 different schools were enrolled in the study in 2012 (Qazvin province, Iran). Demographics and other information as well as the history of Varicella were obtained through a self-administered questionnaire. Blood samples were collected to determine the Varicella IgG levels via an enzyme-linked immunosorbent assay. A statistical analysis was performed by calculating prevalences and their 95% confidence intervals. Sensitivity, specificity, positive and negative predictive values, Cohen's kappa and positive and negative likelihood ratios of recalled history were determined. p < 0.05 was considered statistically significant. Results: The mean age of participants was 21.3±4.3 years. Seropositivity rate was 74.5%. The relationships between marital status, number of family members, and acquired VZV history with immunity against the virus were statistically significant. The overall rate of reported history was 57%. The positive and negative predictive values of self-reported history of Varicella were 91% and 47.3%, respectively. Conclusions: Immunization of students of Iranian medical sciences seems logical in the near future. Also, they should be tested for Varicella immunity regardless of the history of previous infection

Bioconversion of lignocellulosic hydrolysate to acetic acid using Moorella thermoacetica

Thesis (Master's)--University of Washington, 2015A systematic study of bioconversion of lignocellulosic sugars to acetic acid by Moorella thermoacetica strain ATCC 39073 was conducted. Four different hydrolysates obtained after steam pretreatment of lignocellulosic biomass were selected and fermented to acetic acid in batch fermentations. The bacterial strain (ATCC 39073) can effectively ferment xylose and glucose in steam exploded hydrolysates from wheat straw, forest residues, switchgrass, and sugarcane straw to acetic acid. This homoacetogen prefers xylose over glucose. The highest acetic acid yield obtained was in steam pretreated sugarcane straw hydrolysate and the lowest in forest residues hydrolysate (71% and 39% of theoretical respectively based on total sugars). This acetogen can partially consume arabinose, galactose and mannose within 72 h of fermentation. Acetic acid yield in forest residues was adversely affected by high concentration of arabinose, galactose and mannose. Glucose to xylose ratio has a direct effect on production yield. It was also observed that M. thermoacetica can tolerate process derived inhibitory compounds from steam explosion pretreatment (total phenolics up to 3 g/L and furans up to 0.5 g/L)