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41.
Background and objectives: The objective of this study was to investigate the effects of desensitization protocols using intravenous Ig with or without plasmapheresis in patients with donor-specific anti-HLA antibodies on prevention of antibody-mediated rejection and downregulation of donor-specific antibodies.Design, setting, participants, & measurements: Thirty-five complement-dependent cytotoxicity T cell cross-match–negative but complement-dependent cytotoxicity B cell and/or flow cytometry cross-match–positive kidney transplant recipients were treated with high-dosage intravenous Ig plus Thymoglobulin induction treatment. Donor-specific antibody strength was stratified as strong, medium, or weak by Luminex flow beads. Group 1 patients had weak/moderate and group 2 strong donor-specific antibodiesResults: Whereas no group 1 patients had acute rejection, 66% of group 2 had acute rejection (44% antibody-mediated rejection, 22% cellular rejection). The protocol was then changed to the addition of peritransplantation plasmapheresis to patients with strong donor-specific antibodies (group 3). This change resulted in a dramatic decrease in the acute rejection rate to 7%. During a median 18 mo of follow-up, patient survival was 100, 100, and 93% and graft survival was 100, 78, and 86% in groups 1, 2, and 3, respectively. During follow-up, 17 (52%) patients lost donor-specific antibodies completely, and 10 (30%) lost some of donor-specific antibodies and/or decreased the strength of existing donor-specific antibodies.Conclusions: These results indicated that in patients with strong donor-specific antibodies, the addition of plasmapheresis to high-dosage intravenous Ig decreases the incidence of acute rejection. The majority of the patients, whether they received intravenous Ig alone or with plasmapheresis, lost their donor-specific antibodies during follow-up.Donor-specific anti-HLA antibodies (DSA) in patients who are sensitized through pregnancy, previous blood transfusions, or organ transplantation is an important obstacle in kidney transplantation. Sensitized patients wait longer on the deceased-donor transplantation list, may not receive a transplant, and may have greater morbidity and mortality. Some sensitized patients may have living donor candidates, but transplantation cannot be performed because of cross-match positivity. Recent desensitization protocols using the combination of plasmapheresis (PP) or immunoadsorption to remove DSA and/or intravenous Ig (IVIG) and rituximab to downregulate antibody-mediated immune responses have made kidney transplantation feasible by abrogating complement-dependent cytotoxicity (CDC) T cell cross-match positivity. In previous studies, two protocols were examined: High-dosage IVIG (2.0 g/kg) (13) and PP with low-dosage IVIG (100 mg/kg after each PP session) (48); however, acute antibody-mediated rejection (AMR) continued to be an important barrier and was still observed in at least 30 to 40% of the recipients included in these desensitization protocols, even when rituximab was added to the protocol.Whereas CDC T cell cross-match positivity is an absolute contraindication to kidney transplantation, the clinical significance of CDC B cell or flow cytometry (FC) T and/or B cell cross-match positivity are less clear. Most studies have demonstrated that CDC T cell cross-match–negative but CDC B or FC T/B cell cross-match–positive patients with DSA are at higher risk for developing acute cellular, antibody-mediated, and chronic rejection and graft loss (9,10). The role of desensitization protocols for these patients has not been studied in a large cohort. We previously reported our initial experience using low-dosage IVIG (300 mg/kg) and Thymoglobulin induction treatment in 15 patients (11,12). Because of early AMR in three patients, the IVIG dosage was increased to a total of 2.0 mg/kg in subsequent patients. Now, we present our experience in CDC T cell–negative but CDC B cell or FC T and/or B cell cross-match–positive kidney transplant recipients with DSA, who were stratified according to mean fluorescence indices of Luminex flow beads. The results showed that patients with strong DSA were at much higher risk for developing acute AMR early after transplantation, and the addition of peritransplantation PP to high-dosage IVIG and Thymoglobulin treatment significantly decreased the incidence of AMR. The majority of the patients, whether they received IVIG alone or with PP, lost DSA during follow-up.  相似文献   
42.
Pasteurella multocida (P. multocida) is an important pathogen of various domestic animals. The outer membrane proteins (OMPs) play a major role in pathogenesis and immunogenicity of P. multocida. The aim of the study was to develop indirect enzyme linked immuno sorbant assay (ELISA) based on OMPs to ascertain the antibody titers in animals post-infection or to gauge the potency of vaccine. The OMPs were extracted and purified from P. multocida P:52 (vaccine strain) and P. multocida B:2 isolated from natural outbreak of Haemorrhagic septicaemia (HS) and analyzed on SDS PAGE and through western blot. The OMPs profile of the vaccine strain and the isolate from the natural outbreak of HS were found to be similar. Optimization of various components viz. coating antigens, anti-species conjugate, etc. were carried out against both anti-P. multocida hyper immune and pre immune serum. Validation of OMP based indirect ELISA assay to measure immune response against P. multocida in bovine revealed 91% diagnostic sensitivity (DSN) and about 100% diagnostic specificity (DSP) at 25% cut off. OMP based indirect ELISA was found to be more specific, but less sensitive as compared to WCL based assay.Key Words: Diagnostic sensitivity, Diagnostic specificity, Indirect ELISA, Outer membrane proteins, Pasteurella multocida  相似文献   
43.
Objectives. We explored the relationship between mental health and type 2 diabetes among women in New Delhi, India, in 2011.Methods. We recruited a convenience sample of 184 diabetic women from 10 public and private clinics. They completed a finger-stick blood test and a questionnaire assessing demographic characteristics, depression and anxiety symptoms, and diabetes-related disabilities restricting their performance of daily tasks. A subsample of 30 women participated in follow-up qualitative interviews at their homes.Results. More than one quarter of our sample of diabetic women reported high levels of anxiety symptoms, whereas 18% reported high levels of depression symptoms. Anxiety symptoms were patterned according to recency of diabetes diagnosis, with 40% of women diagnosed less than 2 years before their interview reporting high anxiety symptom levels, as opposed to 23% of women diagnosed more than 2 years in the past. Depression and anxiety scores differed with respect to their relationship to recency of diagnosis, number of children, blood glucose level, and functional disabilities restricting performance of daily tasks.Conclusions. Screening for anxiety among people with diabetes has been overlooked in the past. Anxiety appears more prevalent than depression, especially during the first 2 years of the disease.Chronic and noncommunicable diseases (CNCDs) are emerging as major research foci in tandem with their increasing global prevalence. In both developed and developing regions of the world, including South Asia, CNCDs are now leading causes of morbidity and mortality.1 With their complicated etiologies, long durations, frequent comorbidities, and lack of “cures,” CNCDs pose unique challenges for global health. In particular, CNCDs can have far-reaching personal and interpersonal effects that are difficult to capture in epidemiological and biomedical studies, yet are crucial to the trajectory of these illnesses. It is therefore necessary to adopt an analytic perspective that embraces the complex natural histories of chronic diseases as well as their potential comorbidities.A particularly well-studied instance of comorbidity is the overlap between type 2 diabetes and depression. This comorbidity has been estimated to affect anywhere from 11% to 71% of individuals with diabetes, depending on the population studied and the diagnostic method used,2–4 and it is strongly associated with physical and mental morbidity and even mortality.2–6 Clinical and epidemiological studies have demonstrated the cyclical nature of diabetes–depression comorbidity,7 and medical social scientists have identified some of the social determinants linking the 2 conditions, including socioeconomic status (SES),8 the social significance of foods and activity patterns,9,10 and gendered social roles.11–13The similarity between depression and anxiety symptoms, etiologies, and methods of diagnosis, as well as their common comorbidity,14 suggests that anxiety should be as great a concern in CNCD comorbidity as depression. Indeed, according to findings from the World Mental Health Survey, diabetes is roughly equally associated with depression and anxiety around the world.15 Yet, with one very recent exception,16 the potential impact of anxiety disorders on diabetes has received much less attention than diabetes–depression comorbidity.Here we detail the findings of an exploratory mixed-method study of type 2 diabetes (hereafter diabetes) and mental health symptoms among women in New Delhi, India, with a special focus on symptoms of anxiety. India is home to the second-largest population of individuals with type 2 diabetes in the world.17 The limited existing evidence suggests that depression and anxiety are also common,18–20 although prevalence studies are few. Little is known about how diabetes and poor mental health co-occur in this setting or about what social determinants might shape their comorbidity.On the basis of the observation that high levels of anxiety symptoms were significantly more prevalent than depression symptoms in our study, we believe that it is important to consider the causes and correlates of anxiety comorbid with diabetes. We propose a socially grounded interpretation of the patterns emerging from our preliminary data and offer suggestions for future research designed to assess the broader applicability of this interpretation for CNCD–anxiety comorbidity in other contexts.  相似文献   
44.
International Journal of Legal Medicine - Age determination of insects collected from vertebrate remains is an essential step in estimating time since colonization as related to the post-mortem...  相似文献   
45.
OBJECTIVE: We have recently shown a decreased expression of Gialpha proteins and associated functions in aorta from short term (5 days) streptozotocin-induced diabetic rats. Since hyperglycemia is one of the underlying causes of diabetes-induced cardiovascular complications, it was of interest to examine if hyperglycemia may play a direct role in down regulating the expression of Gialpha in vascular smooth muscle cells of diabetic subjects. For this, the effect of high glucose treatment on Gialpha protein expression and adenylyl cyclase signaling in intact aorta and vascular smooth muscle cells (A10 cells) was investigated. METHODS: The cells were grown in normal glucose (5.5 mM) medium and were subsequently exposed to high glucose (26 mM) or normal medium for various time periods (24-96 h). Aorta from control rats were exposed to normal and high glucose medium for 72 h. The levels of G-proteins were determined by immunoblotting using specific antibodies. Adenylyl cyclase activity stimulated or inhibited by agonists was determined to examine the functions of G-proteins. RESULTS: The levels of Gialpha-2 and Gialpha-3 proteins in membranes from A10 cells and aorta exposed to high glucose for 3 or 4 days were significantly decreased as compared to control cells and control aorta, respectively, whereas the levels of Gsalpha protein were not altered. In addition, receptor-dependent and -independent functions of Gialpha proteins were attenuated in hyperglycemic cells, as demonstrated by inhibition of forskolin (FSK)-stimulated adenylyl cyclase activity by low concentration of GTPgammaS or by angiotensin II (Ang II), oxotremorine or C-ANP(4-23) (a ring deleted analog of atrial natriuretic peptide). On the other hand, the stimulatory effects of GTPgammaS, glucagon, isoproterenol, FSK and sodium fluoride on adenylyl cyclase were significantly augmented in hyperglycemic cells as compared to control cells, whereas basal adenylyl cyclase activity was significantly lower in hyperglycemic cells as compared to control cells. CONCLUSION: These results indicate that high glucose decreased the levels and functions of Gi proteins in A10 VSMC and aorta. It may thus be suggested that decreased levels and activity of Gi proteins and adenylyl cyclase signaling induced by hyperglycemia may be one of the important mechanisms contributing to the cardiovascular complications associated with diabetes.  相似文献   
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47.
Mitochondrial dysfunctions cause numerous human disorders. A platform technology based on biodegradable polymers for carrying bioactive molecules to the mitochondrial matrix could be of enormous potential benefit in treating mitochondrial diseases. Here we report a rationally designed mitochondria-targeted polymeric nanoparticle (NP) system and its optimization for efficient delivery of various mitochondria-acting therapeutics by blending a targeted poly(d,l-lactic-co-glycolic acid)-block (PLGA-b)-poly(ethylene glycol) (PEG)-triphenylphosphonium (TPP) polymer (PLGA-b-PEG-TPP) with either nontargeted PLGA-b-PEG-OH or PLGA-COOH. An optimized formulation was identified through in vitro screening of a library of charge- and size-varied NPs, and mitochondrial uptake was studied by qualitative and quantitative investigations of cytosolic and mitochondrial fractions of cells treated with blended NPs composed of PLGA-b-PEG-TPP and a triblock copolymer containing a fluorescent quantum dot, PLGA-b-PEG-QD. The versatility of this platform was demonstrated by studying various mitochondria-acting therapeutics for different applications, including the mitochondria-targeting chemotherapeutics lonidamine and α-tocopheryl succinate for cancer, the mitochondrial antioxidant curcumin for Alzheimer’s disease, and the mitochondrial uncoupler 2,4-dinitrophenol for obesity. These biomolecules were loaded into blended NPs with high loading efficiencies. Considering efficacy, the targeted PLGA-b-PEG-TPP NP provides a remarkable improvement in the drug therapeutic index for cancer, Alzheimer’s disease, and obesity compared with the nontargeted construct or the therapeutics in their free form. This work represents the potential of a single, programmable NP platform for the diagnosis and targeted delivery of therapeutics for mitochondrial dysfunction-related diseases.  相似文献   
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50.
ObjectiveTo evaluate the efficacy and complications of lower eyelid suspension with the modified Safdarjung hospital technique using 5:0 polypropylene suture for punctal ectropion.Study designProspective case series.MethodThirty one eyelids in 19 patients with mild and moderate ectropion and all types of laxity including involutional and paralytic were included. All patients underwent lower eyelid suspension with the modified Safdarjung hospital technique. A 5:0 polypropylene suture was passed in the pre-tarsal plane between the attachments of the lateral and medial canthal tendons near their insertion at the orbital rim. Successful outcome was judged by the anatomical restoration of the apposition of the punctum to the globe in the upward gaze and the physiological relief of epiphora. The recurrence of lid laxity, overall lid/globe apposition and complications were also noted.ResultsAt 1 year follow up anatomical success was achieved in 28 (90%) patients and functional success noted in 27 (87%) patients. Recurrence of lid laxity was noted in 2 patients. There was a suture exposure in one case and a suture granuloma in another case. The results did not correlate to the degree of ectropion and type of laxity.ConclusionLower eyelid suspension using 5:0 polypropylene suture is a useful procedure for the treatment of involutional and paralytic punctal ectropion. It is simple and effective with minimal complications. However, the effect on scleral show and the concern related to suture material biodegradation over years needs to be further evaluated.  相似文献   
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