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941.
942.
This study was designed to examine the prevalence of stigma and its underlying factors in two large Indian cities. Cross-sectional interview data were collected from 1,076 non-HIV patients in multiple healthcare settings in Mumbai and Bengaluru, India. The vast majority of participants supported mandatory testing for marginalized groups and coercive family policies for PLHA, stating that they “deserved” their infections and “didn’t care” about infecting others. Most participants did not want to be treated at the same clinic or use the same utensils as PLHA and transmission misconceptions were common. Multiple linear regression showed that blame, transmission misconceptions, symbolic stigma and negative feelings toward PLHA were significantly associated with both stigma and discrimination. The results indicate an urgent need for continued stigma reduction efforts to reduce the suffering of PLHA and barriers to prevention and treatment. Given the high levels of blame and endorsement of coercive policies, it is crucial that such programs are shaped within a human rights framework.  相似文献   
943.
944.
Acute kidney injury (AKI) is a frequently encountered complication in decompensated chronic liver disease (CLD) with an estimated prevalence of 20%–50% among hospitalized patients. AKI often heralds the onset of a downhill course in the natural history of CLD. Serum creatinine has several limitations as a stand-alone marker of AKI in patients with decompensated CLD. The concept of hepatorenal syndrome, the prototype of AKI in decompensated CLD, has evolved tremendously over recent years. There is emerging evidence of an additional “structural” component in the pathophysiology of hepatorenal syndrome-AKI, which was previously identified as a purely “functional” form of renal impairment. Lacunae in the existent biochemical arsenal for diagnosis and prognosis of AKI have fueled enthusiastic research in the field of novel biomarkers of kidney injury in patients with cirrhosis. The advent of these biomarkers provides a crucial window of opportunity to improve the diagnosis and clinical outcomes of this vulnerable cohort of patients. This review summarizes the dynamic concept of renal dysfunction in CLD and the available literature on the role of novel biomarkers of AKI in assessing renal function, identifying AKI subtypes, and predicting prognosis. There is special emphasis on the renal tubular injury marker, neutrophil gelatinase-associated lipocalin, the most exhaustively studied biomarker of AKI in the CLD population.  相似文献   
945.
A nulliparous woman aged 45 years was referred to us with painful swelling in left lower limb. She underwent laparoscopic hysterectomy for menorrhagia 12 days prior to the admission. The laparoscopic surgery was completed in 90 min without blood loss and blood transfusion. The size of the uterus was approximately 12 weeks. Duplex scan of the left lower limb confirmed thrombosis of the left external iliac vein, femoral vein, popliteal vein and tibial veins. On examination the laparoscopic puncture wounds healed well. She was hospitalized for initial anticoagulation with low molecular weight heparin (Enoxapain 1 mg/kg body weight twice daily) and compression bandages. Histological examination of the hysterectomy specimen was noted to be benign (Adenomyosis and cervical Leiomyoma). She responded to anticoagulation therapy and was discharged with an advice to attend the follow up clinic for long term anticoagulation advice for the next 6 months to prevent recurrent thromboembolic episodes.  相似文献   
946.
Nanofibers and nanomaterials are potentially recent additions to materials in relation to tissue engineering (TE). TE is the regeneration of biological tissues through the use of cells, with the aid of supporting structures and biomolecules. Mimicking architecture of extracellular matrix is one of the challenges for TE. Biodegradable biopolymer nanofibers with controlled surface and internal molecular structures can be electrospun into mats with specific fiber arrangement and structural integrity for drug delivery and TE applications. The polymeric materials are widely accepted because of their ease of processability and amenability to provide a large variety of cost-effective materials, which help to enhance the comfort and quality of life in modern biomedical and industrial society. Today, nanotechnology and nanoscience approaches to scaffold design and functionalization are beginning to expand the market for drug delivery and TE is forming the basis for highly profitable niche within the industry. This review describes recent advances for fabrication of nanofiber scaffolds and interaction of cells in TE.  相似文献   
947.
We evaluated the role of regulatory T cells (CD4(+) CD25(+) Foxp3(+) cells, Tregs) in human Mycobacterium tuberculosis infection. Tregs were expanded in response to M. tuberculosis in healthy tuberculin reactors, but not in tuberculin-negative individuals. The M. tuberculosis mannose-capped lipoarabinomannan (ManLAM) resulted in regulatory T cell expansion, whereas the M. tuberculosis 19-kDa protein and heat shock protein 65 had no effect. Anti-IL-10 and anti-TGF-beta alone or in combination, did not reduce expansion of Tregs. In contrast, the cyclooxygenase enzyme-2 inhibitor NS398 significantly inhibited expansion of Tregs, indicating that prostaglandin E2 (PGE2) contributes to Treg expansion. Monocytes produced PGE2 upon culturing with heat-killed M. tuberculosis or ManLAM, and T cells from healthy tuberculin reactors enhanced PGE2 production by monocytes. Expanded Tregs produced significant amounts of TGF-beta and IL-10 and depletion of Tregs from PBMC of these individuals increased the frequency of M. tuberculosis-responsive CD4(+) IFN-gamma cells. Culturing M. tuberculosis-expanded Tregs with autologous CD8(+) cells decreased the frequency of IFN-gamma(+)cells. Freshly isolated PBMC from tuberculosis patients had increased percentages of Tregs, compared to healthy tuberculin reactors. These findings demonstrate that Tregs expand in response to M. tuberculosis through mechanisms that depend on ManLAM and PGE2.  相似文献   
948.
Ma K  Chan CK  Liao S  Hwang WY  Feng Q  Ramakrishna S 《Biomaterials》2008,29(13):2096-2103
Interactions between bone marrow-derived hematopoietic stem cells (BM-HSCs) and their local microenvironment are an integral part of signaling control of BM-HSCs migration, proliferation and differentiation. We hypothesized that both substrate topographical and biochemical cues promote BM-HSCs adhesive behaviors, which are crucial for BM-HSCs' homing, self-renewal and lineage commitment within their microenvironment. We employed electrospinning technique to fabricate nanofiber scaffolds (NFS) with poly(dl-lactide-co-glycolide) blended with collagen I. NFS was further coated with E-selectin, a critical adhesive biomolecule. Capture efficiency study showed that blended NFS, after coated with E-selectin, significantly increased cell capture percentage from 23.40% to 67.41% within 30 min and from 29.44% to 70.19% within 60 min of incubation at room temperature. This study highlights the potential of using a biomimetic scaffold to design a site-specific niche-like unit for facilitating proliferation or differentiation functions of BM-HSCs.  相似文献   
949.
950.
Flexible fiber membranes for pollutant removal have received increasing attention due to their high adsorption performance and easy recycling characteristics. However, due to the lack of environmentally friendly regeneration, some adsorption membranes have low regeneration efficiency, especially in terms of chemical adsorption, so they lack reusability. This study prepares a series of conducting polymer [PAn (polyaniline) or PPy (polypyrrole) or PTh (polythiophene)] graphene quantum dots (GQDs, the size of GQDs is about 20 nm)/TiO2 ternary fiber membranes via a facile electrospinning method with chemical deposition. Remarkably, this creates an anatase TiO2 and π-conjugated system. The combination is beneficial to the photocatalytic degradation of organic pollutants, showing synergistic promotion in both the degradation rate and the degree of decomposition. The UV-vis test shows that the combination of GQDs broadens the optical response threshold of TiO2, from near ultraviolet region excitation to visible region excitation. At the same time, the conductive polymer load further reduces the energy required for photogenerated electron transfer, which theoretically improves the degradation effect. Photocatalytic degradation tests showed that the PTh/GQDs/TiO2 fiber membrane exhibited significant high photocatalytic activity of visible-light in the methylene blue (MB) and TC degradation. The degradation rate level is 92.90% and 80.58%, respectively and the MB removal is more than 4 times that of bare TiO2 membrane. After photocatalytic regeneration four times, the regeneration efficiency can be maintained above 95%. Notably, various experimental results show that the interface charge transfer mechanism between GQDs/TiO2 and PTh follows the Z-scheme heterojunction, which maximizes the retention of strong reducing electrons and oxidation holes. In the degradation, the active species of ·O2 and ·OH, make different contributions in the photocatalysts, which oxidize and break down the pollutant molecules into small molecules and then to harmless substances. According to the electronegativity difference of the material itself, PTh acts as electron acceptor in the degradation system, and TiO2 fiber membrane doped with GQDs acts as electron donor. The present research, not only offers feasibility of the PTh/GQDs/TiO2 flexible fiber membrane as an environment-friendly catalyst, but also motivates researchers to develop flexible fiber materials for future photocatalytic technology.

Flexible fiber membranes for pollutant removal have received increasing attention due to their high adsorption performance and easy recycling characteristics.  相似文献   
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