15 research outputs found

    Relationship of primary immune thrombocytopenic purpura and atopia among children: a case control study

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    Atopic dermatitis (AD) is a chronic disease affecting 10�30 of children and 2�10 of adults worldwide. It is manifested by the pruritus eczema lesions on the skin. Immune thrombocytopenic purpura (ITP) is the most common cause of acute onset of thrombocytopenia in childhood. The aim of this study was association of primary immune thrombocytopenic purpura and atopia among children. This case control study was performed on patients with acute and chronic ITP who were confirmed by a hematologist. The control group was also selected from the siblings of the patients who were healthy and almost matched by age and sex with the patient group. Data were entered into a questionnaire under the SPSS-20 program, and demographic data were analyzed descriptively. In the present study, 120 patients were enrolled, 60 of whom were in the patient group and 60 in the control group. Mean age was 95 and 98 months for patients and control. This study showed a significant association of ITP with allergic rhinitis (P = 0.02), atopic dermatitis (P = 0.004), itching (P = 0.042), and dry skin (P = 0.015). However, no significant relationship was found between ITP and asthma (P-value = 0.18). This study does not reveal the causality between atopy and ITP but clearly shows the association between atopy and ITP disease, so the prevalence of atopy in ITP patients is higher than the normal population. According to the results of this study, it is necessary to investigate the cause of atopy and ITP and to find other immunological and possibly genetic commonalities. © 2020, The Author(s)

    Fouling of a microfiltration membrane by humic-like substances:A mathematical approach to modelling permeate flux and membrane retention

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    Abstract Membrane retention of the humic-like substances present in a soluble microbial products (SMP) suspension was studied by using a dead-end filtration system. The SMP suspension was extracted from the sludge of an enhanced biological phosphorus removal-membrane bioreactor. Our results showed that both adsorption and steric retention of the humic-like substances governed their transport through the membrane during the filtration. The adsorption, which followed pseudo-first order kinetics, did not cause substantial decline of permeate flux. The steric retention, on the other hand, formed a gel layer, which in turn led to a major decrease in the flux. The reduction of permeate flux was well predicted by cake filtration theory. Based on the adsorption and the steric retention, a new model was developed for predicting the overall membrane retention of the humic-like substances. The general trend of the modelled overall retention was in partial agreement with the experimental results.</jats:p

    Irreversible fouling of membrane bioreactors due to formation of a non-biofilm gel layer

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    Extra-cellular polymeric substances (EPS), known to contribute to fouling in membrane bio-reactors (MBRs), are generally divided into bound and free EPS. The free EPS are able to form a gel layer on the membrane active surface. The mechanisms involved in formation of such layer and its effects on performance of the MBR membranes were studied. The free EPS, extracted by centrifugation and microfiltration, contained a significant amount of humic-like substances. Under static contact to the membrane, adsorption of humic-like substances to the membrane occurred and could be explained by conventional adsorption kinetics. Due to static adsorption, surface roughness of the membrane declined significantly, indicating that adsorbed matters to the membrane filled the cavities of the membrane surface. Filtration of the free EPS caused 50% water flux decline. The fouling resistance linearly increased with the amount of the humic-like substances retained during filtration as predicted by gel growth theory. A low pressure backwash could re-establish the water flux only up to 70%.</jats:p
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