52 research outputs found

    Wind energy assessment as a source of power generation in Bangladesh

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    Wind energy has been considered one of the most popular forms of renewable energy. It has been widely considered for the generation of electricity for its low maintenance cost and negligible effect on environmental pollution. The purpose of this research is to evaluate and compare the wind energy potential in seven different districts of Bangladesh including Barisal, Chittagong, Dhaka , Khulna, Rajshahi, Rangpur, and Sylhet. Data had been recorded on daily basis for the consecutive five years from 2015 until 2 019 and analysed using Weibull distribution function various essential parameters such as wind speed, wind energy density and wind power density. Results show that the monthly average wind speed varies between 0.5 m/s to 2.10 m/s for all the divisions except Chittagong where it is in the range between 3 m/s and 4.5 m/s. Similarly, the maximum wind power density and wind energy density were also found in the Chittagong division with annual densities that range between 51.86967 W

    Direct torque control induction motor drives

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    This paper presents an implementation of a direct torque control (DTC) strategies to control the operation induction motor (IM). The aim is to control effectively the torque and flux. Torque control of an induction motor base on DTC strategy has been developed and a comprehensively study in this thesis. Direct torque control is the first technology to control the real motor control variable of torque and flux. This method made the motor more accurate and fast torque control, high dynamic speed response and simple to control. This report presents a principle of the DTC; switching table, and selection of the amplitude of the hysteresis band of torque and flux. The basic dynamic performance of DTC is investigated. The performance is including in when the motor in starting drives and when motor in nominal value. The performance of this control method has been demonstrated by simulation using a versatile simulation package, MATLAB/SIMULINK. The author also present the simulation results related to the theoretical aspects mentioned in the paper. The result shows that the proposed direct torque control is capable to control the operation of the induction moto

    Topical steroid therapy induces pro-tolerogenic changes in Langerhans cells in human skin

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    We have investigated the efficacy of conditioning skin Langerhans cells (LCs) with agents to promote tolerance and reduce inflammation, with the goal of improving the outcomes of antigen-specific immunotherapy. Topical treatments were assessed ex vivo, using excised human breast skin maintained in organ bath cultures, and in vivo in healthy volunteers by analysing skin biopsies and epidermal blister roof samples. Following topical treatment with a corticosteroid, TNF-α levels were reduced in skin biopsy studies and blister fluid samples. Blister fluid concentrations of MCP-1, MIP-1α, MIP-1β and IP-10 were also reduced, while preserving levels of IL-1α, IL-6, IL-8 and IL-10. Steroid pre-treatment of the skin reduced the ability of LCs to induce proliferation, whilst supernatants showed an increase in the IL-10/IFN-γ ratio. Phenotypic changes following topical steroid treatment were also observed, including reduced expression of CD83 and CD86 in blister derived LCs, but preservation of the tolerogenic signalling molecules ILT3 and PD-1. Reduced expression of HLA-DR, CD80 and CD86 were also apparent in LCs derived from excised human skin. Topical therapy with a vitamin D analogue (calcipotriol) and steroid, calcipotriol alone or Vitamin A elicited no significant changes in the parameters studied. These experiments suggest that pre-conditioning the skin with topical corticosteroid can modulate LCs by blunting their pro-inflammatory signals and potentially enhancing tolerance. We suggest that such modulation prior to antigen specific immunotherapy might provide an inexpensive and safe adjunct to current approaches to treat autoimmune diseases

    Prescribing costs of hypoglycaemic agents and associations with metabolic control in Wales; a national analysis of primary care data

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    Aims: There has been a dramatic increase in hypoglycaemic agent expenditure. We assessed the variability in prescribing costs at the practice level and the relationship between expenditure and the proportion of patients achieving target glycaemic control. Methods: We utilized national prescribing data from 406 general practices in Wales. This was compared against glycaemic control (percentage of patients achieving a HbA1c level < 59 mmol/mol in the preceding 12 months). Analyses were adjusted for the number of patients with diabetes in each general practice and the Welsh Index of Multiple Deprivation. Results: There was considerable heterogeneity in hypoglycaemic agent spend per patient with diabetes, Median = £289 (IQR 247–343) range £31.1–£1713. Higher total expenditure was not associated with improved glycaemic control B(std) = −0.01 (95%CI –0.01, 0.002) p = 0.13. High‐spend practices spent more on SGLT2 inhibitors (16 vs. 9% p < 0.001) and GLP‐1 agonists (13 vs. 11% p < 0.001) and less on insulin (34 vs. 42% p < 0.001), biguanides (9 vs. 11% p = 0.001) and sulphonylureas (2 vs. 3% p < 0.001) than low spend practices. There were no differences in the pattern of drug prescribing between high spend practices with better glycaemic control (mean 68% of patients HbA1c <59 mmol/mol) and those with less good metabolic control (mean 58% of patients HbA1c <59 mmol/mol). Conclusions: Spend on hypoglycaemic agents is highly variable between practices and increased expenditure per patient is not associated with better glycaemic control. Whilst newer, more expensive agents have additional benefits, in individuals where these advantages are more marginal widespread use of these agents has important cost implications

    First-in-human, double-blind, randomized phase 1b study of peptide immunotherapy IMCY-0098 in new-onset type 1 diabetes

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    : Background : Type 1 diabetes (T1D) is a CD4+ T cell-driven autoimmune disease characterized by the destruction of insulin-producing pancreatic β-cells by CD8+ T cells. Achieving glycemic targets in T1D remains challenging in clinical practice; new treatments aim to halt autoimmunity and prolong β-cell survival. IMCY-0098 is a peptide derived from human proinsulin that contains a thiol-disulfide oxidoreductase motif at the N-terminus and was developed to halt disease progression by promoting the specific elimination of pathogenic T cells. Methods: This first-in-human, 24-week, double-blind phase 1b study evaluated the safety of three dosages of IMCY-0098 in adults diagnosed with T1D < 6 months before study start. Forty-one participants were randomized to receive four bi-weekly injections of placebo or increasing doses of IMCY-0098 (dose groups A/B/C received 50/150/450 μg for priming followed by three further administrations of 25/75/225 μg, respectively). Multiple T1D-related clinical parameters were also assessed to monitor disease progression and inform future development. Long-term follow-up to 48 weeks was also conducted in a subset of patients. Results: Treatment with IMCY-0098 was well tolerated with no systemic reactions; a total of 315 adverse events (AEs) were reported in 40 patients (97.6%) and were related to study treatment in 29 patients (68.3%). AEs were generally mild; no AE led to discontinuation of the study or death. No significant decline in C-peptide was noted from baseline to Week 24 for dose A, B, C, or placebo (mean change − 0.108, − 0.041, − 0.040, and − 0.012, respectively), suggesting no disease progression. Conclusions: Promising safety profile and preliminary clinical response data support the design of a phase 2 study of IMCY-0098 in patients with recent-onset T1D. Trial registration: IMCY-T1D-001: ClinicalTrials.gov NCT03272269; EudraCT: 2016–003514-27; and IMCY-T1D-002: ClinicalTrials.gov NCT04190693; EudraCT: 2018–003728-35

    Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

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    Background The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population. Methods EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110. Findings Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5–2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62–0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16–1·59), representing a 50% (42–58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1). Interpretation In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease. Funding Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council

    Phenotypic Analysis of Human Lymph Nodes in Subjects With New-Onset Type 1 Diabetes and Healthy Individuals by Flow Cytometry.

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    Background: Ultrasound guided sampling of human lymph node (LN) combined with advanced flow cytometry allows phenotypic analysis of multiple immune cell subsets. These may provide insights into immune processes and responses to immunotherapies not apparent from analysis of the blood. Methods: Ultrasound guided inguinal LN samples were obtained by both fine needle aspiration (FNA) and core needle biopsy in 10 adults within 8 weeks of diagnosis of type 1 diabetes (T1D) and 12 age-matched healthy controls at two study centers. Peripheral blood mononuclear cells (PBMC) were obtained on the same occasion. Samples were transported same day to the central laboratory and analyzed by multicolour flow cytometry. Results: LN sampling was well-tolerated and yielded sufficient cells for analysis in 95% of cases. We confirmed the segregation of CD69+ cells into LN and the predominance of CD8+ Temra cells in blood previously reported. In addition, we demonstrated clear enrichment of CD8+ naïve, FOXP3+ Treg, class-switched B cells, CD56bright NK cells and plasmacytoid dendritic cells (DC) in LNs as well as CD4+ T cells of the Th2 phenotype and those expressing Helios and Ki67. Conventional NK cells were virtually absent from LNs as were Th22 and Th1Th17 cells. Paired correlation analysis of blood and LN in the same individuals indicated that for many cell subsets, especially those associated with activation: such as CD25+ and proliferating (Ki67+) T cells, activated follicular helper T cells and class-switched B cells, levels in the LN compartment could not be predicted by analysis of blood. We also observed an increase in Th1-like Treg and less proliferating (Ki67+) CD4+ T cells in LN from T1D compared to control LNs, changes which were not reflected in the blood. Conclusions: LN sampling in humans is well-tolerated. We provide the first detailed "roadmap" comparing immune subsets in LN vs. blood emphasizing a role for differentiated effector T cells in the blood and T cell regulation, B cell activation and memory in the LN. For many subsets, frequencies in blood, did not correlate with LN, suggesting that LN sampling would be valuable for monitoring immuno-therapies where these subsets may be impacted

    Safety of the use of gold nanoparticles conjugated with proinsulin peptide and administered by hollow microneedles as an immunotherapy in Type 1 diabetes

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    Antigen-specific immunotherapy is immunomodulatory strategy for autoimmune diseases, such as Type 1 diabetes, in which patients are treated with autoantigens to promote immune tolerance, stop autoimmune beta-cell destruction and prevent permanent dependence on exogenous insulin. In this study, human proinsulin peptide C19-A3 (known for its positive safety profile) was conjugated to ultrasmall gold nanoparticles (GNP), an attractive drug delivery platform due to the potential anti-inflammatory properties of gold. We hypothesised that microneedle intradermal delivery of C19-A3 GNP may improve peptide pharmacokinetics and induce tolerogenic immunomodulation and proceeded to evaluate its safety and feasibility in a first-in-human trial. Allowing for the limitation of the small number of participants, intradermal administration of C19-A3 GNP appears safe and well-tolerated in participants with Type 1 diabetes. The associated prolonged skin retention of C19-A3 GNP after intradermal administration offers a number of possibilities to enhance its tolerogenic potential, which should be explored in future studies

    Metabolic and immune effects of immunotherapy with proinsulin peptide in human new-onset type 1 diabetes*

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    Immunotherapy using short immunogenic peptides of disease-related autoantigens restores immune tolerance in preclinical disease models. We studied safety and mechanistic effects of injecting human leukocyte antigen–DR4(DRB1*0401)–restricted immunodominant proinsulin peptide intradermally every 2 or 4 weeks for 6 months in newly diagnosed type 1 diabetes patients. Treatment was well tolerated with no systemic or local hypersensitivity. Placebo subjects showed a significant decline in stimulated C-peptide (measuring insulin reserve) at 3, 6, 9, and 12 months versus baseline, whereas no significant change was seen in the 4-weekly peptide group at these time points or the 2-weekly group at 3, 6, and 9 months. The placebo group’s daily insulin use increased by 50% over 12 months but remained unchanged in the intervention groups. C-peptide retention in treated subjects was associated with proinsulin-stimulated interleukin-10 production, increased FoxP3 expression by regulatory T cells, low baseline levels of activated β cell–specific CD8 T cells, and favorable β cell stress markers (proinsulin/C-peptide ratio). Thus, proinsulin peptide immunotherapy is safe, does not accelerate decline in β cell function, and is associated with antigen-specific and nonspecific immune modulation
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