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61.
To evaluate the mechanism of cyclosporine-induced hyperkalemia, the renin-angiotensin-aldosterone system and renal potassium clearance were compared in ten renal transplant recipients treated with cyclosporine and treated with azathioprine. After stimulation by a low-sodium diet and furosemide, cyclosporine-treated patients demonstrated lower plasma renin activity when supine (1.9 +/- 0.3 v 7.8 +/- 1.4 ng/mL/hr) and after standing (3.0 +/- 0.7 v 12.2 +/- 1.5 ng/mL/hr). Supine plasma aldosterone levels tended to be lower in cyclosporine-treated patients, (4.8 +/- v 10.5 +/- 2.6 ng/dL), although standing plasma aldosterone levels were not different (10.8 +/- 3.0 v 12.3 +/- 2.0 ng/dL). After administration of 0.75 mEq of potassium chloride per kilogram of body weight, cyclosporine-treated patients excreted 52% +/- 7.1% of the potassium load in six hours compared with excretion of 67% +/- 7.0% by the azathioprine-treated patients, although there was no difference in plasma aldosterone levels in response to the potassium load in the two groups. These data suggest that cyclosporine causes suppression of plasma renin activity and a tubular insensitivity to aldosterone, both of which may impair potassium excretion.  相似文献   
62.

Background:

Studies show that immunization among migrant children is poor. India has a dropout rate of 17.7% between Bacillus Calmette-Guιrin (BCG) and measles (District Level Household Survey (DLHS)-3). Haridwar district had the highest dropout rate of 27.4% from BCG to diphtheria, pertussis, and tetanus (DPT) 3 (DLHS-3) in Uttarakhand. We evaluated the Universal Immunization Programme (UIP) among migrants in Haridwar in two blocks.

Materials and Methods:

We developed input, process, and output indicators on infrastructure, human resources, and service delivery. A facility, session site and cross-sectional survey of 180 children were done and proportions for various indicators were estimated. We determined factors associated with not taking vaccination using multivariate analysis.

Results:

We surveyed 11 cold chain centers, 25 subcenters, 14 sessions, and interviewed 180 mothers. Dropouts were supposed to be tracked using vaccination card counterfoils and tracking registers. The dropout rate from BCG to DPT3 was 30%. Lack of knowledge (adjusted odds ratio (AOR) 6.6,95% confidence interval (CI) 2.6–16.7), mother not being decision maker (AOR 4.0,95%CI 1.7–9.2), lack of contact by Accredited Social Health Activist (ASHA; AOR 3.0,95%CI 1.1–7.7), not being given four post-vaccination messages (AOR 7.7, 95% CI 2.9–20.2), and longer duration of stay in Haridwar (AOR 3.0 95% 1.9–7.6) were risk factors for nonimmunization. The reasons stated by mothers included lack of awareness of session site location (67%) and belief that child should only be vaccinated in their resident district (43%).

Conclusions:

There was low immunization coverage among migrants within adequate supervision, poor cold chain maintenance, and improper tracking of dropouts. Mobile immunization teams, prelisting of migrant children, and change in incentives of ASHAs for child tracking were needed. A monitoring plan for sessions and cold chain needed enforcement.  相似文献   
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Background and Purpose

Recently, we have described the use of caerulomycin A (CaeA) as a potent novel immunosuppressive agent. Immunosuppressive drugs are crucial for long-term graft survival following organ transplantation and treatment of autoimmune diseases, inflammatory disorders, hypersensitivity to allergens, etc. The objective of this study was to identify cellular targets of CaeA and decipher its mechanism of action.

Experimental Approach

Jurkat cells were treated with CaeA and cellular iron content, iron uptake/release, DNA content and deoxyribonucleoside triphosphate pool determined. Activation of MAPKs; expression level of transferrin receptor 1, ferritin and cell cycle control molecules; reactive oxygen species (ROS) and cell viability were measured using Western blotting, qRT-PCR or flow cytometry.

Key Results

CaeA caused intracellular iron depletion by reducing its uptake and increasing its release by cells. CaeA caused cell cycle arrest by (i) inhibiting ribonucleotide reductase (RNR) enzyme, which catalyses the rate-limiting step in the synthesis of DNA; (ii) stimulating MAPKs signalling transduction pathways that play an important role in cell growth, proliferation and differentiation; and (iii) by targeting cell cycle control molecules such as cyclin D1, cyclin-dependent kinase 4 and p21CIP1/WAF1. The effect of CaeA on cell proliferation was reversible.

Conclusions and Implications

CaeA exerts its immunosuppressive effect by targeting iron. The effect is reversible, which makes CaeA an attractive candidate for development as a potent immunosuppressive drug, but also indicates that iron chelation can be used as a rationale approach to selectively suppress the immune system, because compared with normal cells, rapidly proliferating cells require a higher utilization of iron.  相似文献   
68.
The development of concise methods for the synthesis of small functionalised spirocyclic molecules is important in the search of new bioactive molecules. To contribute this, here we represent a diastereoselective oxa-hetero-Diels–Alder reaction for the synthesis of novel spiro indanone fused pyrano[3,2-c]chromene derivatives and studied their in vitro anticancer activities. Using previously less explored cyclic ketone i.e. indane-1,3-dione and 3-vinyl-2H-chromene derivatives, we obtained novel spiro-heterocyclic frameworks at the interphase between “drug-like” molecules and natural products. Various spiro indanone fused pyrano[3,2-c]chromene derivatives were synthesized regiospecifically bearing a quaternary stereocenter in high yields (up to 85%) with excellent diastereoselectivity in toluene using 4 Å MS as additive under reflux condition at 120 °C. In vitro cytotoxic studies of these compounds against MCF-7 (breast cancer), HCT-116 (colon cancer), H-357 (oral cancer), MD-MB-231(Breast cancer) cell lines were evaluated by MTT {3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide} assay in vitro. The screening results revealed that many of the compounds are showing moderate to high levels of anticancer activities against the tested cancer cell lines and some displayed potent inhibitory activities in comparison to the commercial anticancer drug 5-fluorouracil (5-FU). Among the series, compound 3′c showed most potent cytotoxicity (15.0–27.5 μM) in three cancer cell lines (MCF-7, HCT-116 and MD-MB-231).

Synthesis of novel spiro indanone fused pyrano[3,2-c]chromene derivatives following hetero-Diels–Alder reaction has been demonstrated and evaluated for their in vitro anticancer activity.  相似文献   
69.
Journal of Thrombosis and Thrombolysis - Thrombotic thrombocytopenic purpura (TTP) which can cause significant mortality is a thrombotic microangiopathy due to deficiency of VWF cleaving protease...  相似文献   
70.
Metabolic Brain Disease - Mild cognitive impairment (MCI) is transition phase between cognitive decline and dementia. The current study aims to investigate altered metabolic pattern in plasma of...  相似文献   
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