Direct Immunofluorescence Results of the Skin Biopsy and Frequency of Systemic Involvement in Children with Henoch-Schonlein Purpura.

OBJECTIVE: Henoch-Schonlein purpura (HSP) is a common vasculitis in children that can present with multi-organ involvement. The aim of this study is to investigate the correlation between direct immunofluorescence (DIF) results and the systemic involvements of the HSP in pediatric patients. MATERIAL AND METHODS: Those HSP patients with leukocytoclastic vasculitis on their biopsies who also had documented immunoglobulin/complement deposition by DIF were included in our study. Their demographic and laboratory data and clinical manifestations were recorded and analyzed. RESULTS: Medical records of 95 patients (1.5-15 years old) were studied. 26.3% of the patients showed renal, 86.3% articular, and 70.3% gastrointestinal involvement. The risk of renal involvement was significantly higher in those with C3 deposition in their skin DIF. IgM deposition was mostly associated with articular involvement. CONCLUSION: Pediatric HSP patients who had C3 deposition in their skin DIF should be selected for further evaluation regarding HSP nephritis.

Investigating the potential of sustainable use of green silica in the green tire industry: a review.

Undoubtedly, with the increasing emission of greenhouse gases and non-biodegradable wastes as the consequence of over energy and material consumption, the demands for environmentally friendly products are of significant importance. Green tires, a superb alternative to traditional tires, could play a substantial part in environmental protection owing to lower toxic and harmful substances in their construction and their higher decomposition rate. Furthermore, manufacturing green tires using green silica as reinforcement has a high capacity to save energy and reduce carbon dioxide emissions, pollution, and raw material consumption. Nevertheless, their production costs are expensive in comparison with conventional tires. In this review article, by studying green tires, the improvement of silica-rubber mixing, as well as the production of green silica from agricultural wastes, were investigated. Not only does the consumption of agricultural wastes save resources considerably, but it also could eventually lead to the reduction of silica production expenses. The cost of producing green silica is about 50% lower than producing conventional silica, and since it weighs about 17% of green silica tires, it can reduce the cost of producing green rubber. Accordingly, we claim that green silica has provided acceptable properties of silica in tires. Apart from the technical aspect, environmental and economic challenges are also discussed, which can ultimately be seen as a promising prospect for the use of green silica in the green tire industry.

Complement deficiency in pediatric-onset systemic lupus erythematosus.

BACKGROUND: Pediatric-onset systemic lupus erythematosus (pSLE) accounts for about 10%-20% of all patients with SLE. Deficiencies in early complement components of the classical pathway are the strong genetic risk factor for the development of SLE. In this study, clinical and laboratory manifestations of both complement-deficient and normal complement pSLE patients were compared. MATERIALS AND METHODS: To investigate clinical and immunological manifestations of pSLE in Iran, 36 consecutive pSLE patients (onset before 18 years) who were followed up over a period of 2 years, were studied. Complement C1q and C2 levels were measured using radial immunodifusion assay and complement C3 and C4 levels were measured using nephelometry. Medical records were retrospectively evaluated from patient database of Children Medical Center Hospital. Data were assessed through descriptive analysis (confidence interval = 95%), paired t-test, and Pearson correlation test. RESULTS: Twenty-one patients (58%) had at least one component of complement deficiency. Ten patients (27%) had low C1q level, 11 patients (30.5%) had low C2, nine patients (25%) had low C3, and four patients (11%) had low C4 level. Serum level of complement in pSLE was significantly lower than the control group, except C4 (P = 0.005). The low C1q patients had an earlier age of onset of disease (P < 0.0001). The cutaneous manifestations were more frequent and much more severe in pSLE with low complement (100% vs. 73%). The frequency of renal and musculoskeletal symptoms was equal, but renal morbidity was more common in pSLE with low complement. Positivity for anti-ds-DNA was less common in pSLE with low complement (71% vs. 86%). CONCLUSION: In pSLE patients with early disease onset and more aggressive SLE manifestations and negative anti-ds-DNA test, complement deficiency should be considered.

An established rat model of inducing reversible acute tubular necrosis.

INTRODUCTION: Acute tubular necrosis (ATN) is a challenging problem that still requires to be studied in animal models. Our aim was to prepare an established experimental model of inducing reversible ATN in rats by determining the optimum duration of ischemia induction to the kidney. MATERIALS AND METHODS: Twenty-four hour after nephrectomy of the right kidney and clamping the pedicle of the left kidney for durations ranging from 10 to 55 minutes, the kidney function and the histologic changes were evaluated. Accordingly, the optimum duration of clamping was determined and in the next step, it was considered for induction of reversible ATN in another group of rats. This group was followed up for 14 days and the pathologic course and function of the kidney were observed. RESULTS: Reversible ATN developed by 47-minute clamping of the renal pedicle. Blood urea nitrogen and serum creatinine levels were elevated up to threefold within 24 hours after the induction of ischemia and they decreased to their reference ranges after 12 and 6 days, respectively. In the histologic study of the kidneys, the least extend of injury was noted by the 14th day following the ATN induction. Even on the 14th day of the follow-up, some signs of ATN remained indicating that the tissue regeneration was not complete yet. CONCLUSIONS: To integrate the experimental models of ATN, a rat model with 47-minute clamping of the renal pedicle for induction of ischemia seems appropriate. The resultant ATN remains for a long duration, while kidney function is alleviated.