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101.
102.
Laboratory diagnosis is an essential component in surveillance of meningococcal epidemics, as it can inform decision-makers of the Neisseria meningitidis serogroup(s) involved and the most appropriate vaccine to be selected for mass vaccination. However, countries most affected face real limitations in laboratory diagnostics, due to lack of resources. We describe current diagnostic tools and examine their cost-effectiveness for use in an epidemic context. The conclusion is that current WHO recommendations to use only the latex agglutination assay (Pastorex) at epidemic onset is cost-effective, but recently developed rapid diagnostic tests for the major epidemic-causing meningococcal serogroups may prove a breakthrough for the future. 相似文献
103.
Jeejeebhoy F Keith M Freeman M Barr A McCall M Kurian R Mazer D Errett L 《American heart journal》2002,143(6):1092-1100
Background Congestive heart failure depletes the myocardium of carnitine, coenzyme Q10 (CoQ10), and taurine—substances known to influence mitochondrial function and cell calcium. We hypothesized that feeding patients a nutritional supplement that contained carnitine, CoQ10, and taurine would result in higher myocardial levels of these nutrients and improve left ventricular function. Methods Forty-one patients who underwent aortocoronary artery bypass with an ejection fraction ≤40% at referral were randomly assigned to a double-blind trial of supplement or placebo. Radionuclide ventriculography was performed at randomization and before surgery. Surgical myocardial biopsies, adjusted for protein content, were analyzed for carnitine, CoQ10, and taurine levels. Results The groups were well matched. Minor exceptions were supplement group versus placebo group for digoxin use (7 vs 0, respectively; P = .009) and age (62 ± 11 years vs 69 ± 5 years, respectively; P = .04). There were significantly higher levels in the treated group compared with the placebo group for myocardial levels of CoQ10 (138.17 ± 39.87 nmol/g wet weight and 56.67 ± 23.08 nmol/g wet weight; P = .0006), taurine (13.12 ± 4.00 μmol/g wet weight and 7.91 ± 2.81 μmol/g wet weight; P = .003), and carnitine (1735.4 ± 798.5 nmol/g wet weight and 1237.6 ± 343.1 nmol/g wet weight; P = .06). The left ventricular end-diastolic volume fell by −7.5 ± 21.7 mL in the supplement group and increased by 10.0 ± 19.8 mL in the placebo group (P = .037). Conclusions Supplementation results in higher myocardial CoQ10, taurine, and carnitine levels and is associated with a reduction in left ventricular end-diastolic volume in patients with left ventricular dysfunction before revascularization. Because the risk of death for surgical revascularization is related to preoperative left ventricular end-diastolic volume, supplementation could improve outcomes. (Am Heart J 2002;143:1092-100.) 相似文献
104.
Moura C Hillion Y Daikha-Dahmane F Eydoux P Fallet C Oury JF Azancot A 《Cardiology in the young》2002,12(3):278-283
Isolated non-compaction of the ventricular myocardium is characterized by numerous and prominent trabeculations and deep intertrabecular recesses. This rare disease is due to an arrest of myocardial morphogenesis. Most cases, when seen in children, are associated with obstructive malformations. Isolated non-compaction is even rarer in childhood, and affects predominantly the myocardium of the left ventricle. Morbidity and mortality resulting from cardiovascular complications is high. In most cases, transplantation is the final option. To our knowledge, this rare cardiac malformation has yet to be diagnosed in the fetus. We report here two sporadic cases, one male and one female, and 2 familial cases, both male, which were diagnosed prenatally and followed by fetal echocardiography. Our study indicates that isolated non-compaction is a primary disorder of early fetal development. Our cross-sectional echocardiographic examinations revealed a fetal cardiomyopathy, with prominent and numerous trabeculations and deep intertrabecular recesses of the myocardium at the apex of the ventricles. In contrast with postnatal experience, we found isolated non-compaction mostly in the right ventricle. Systolic dysfunction was found in all cases. The diagnosis was confirmed by histology in 3 fetuses dying with cardiac failure, and by postnatal cross-sectional echocardiography in the fetus who survived. Two male fetuses belonged to a family in which 3 individuals were subsequently found to be affected. We discuss the issues of prenatal diagnosis, natural history, and myocardial histology. 相似文献
105.
Pericytes are involved in the pathogenesis of cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy 下载免费PDF全文
106.
ETV transcriptional upregulation is more reliable than RNA sequencing algorithms and FISH in diagnosing round cell sarcomas with CIC gene rearrangements 下载免费PDF全文
107.
Farida H. Aidoudi Alessandro Sinopoli Muthumeenal Arunachalam Belabbes Merzougui Brahim Aïssa 《Materials》2021,14(12)
Introducing redox-active moieties into an ionic liquid (IL) structure is an exciting and attractive approach that has received increasing interest over recent years for a various range of energy applications. The so-called redox-active ionic liquids (RAILs) provide a highly versatile platform to potentially create multifunctional electroactive materials. Ionic liquids are molten salts consisting of ionic species, often having a melting point lower than 100 °C. Such liquids are obtained by combining a bulky asymmetric organic cation and a small anion. Here, we report on the synthesis of a novel RAIL, namely 1-butyl-3-methylimidazolium hydroquinone sulfonate ((BMIM)(HQS)). (BMIM)(HQS) was synthesized in a two-step procedure, starting by the quaternization of methylimidazole using butylchloride to produce 1-butyl-3-methylimidazolium chloride ((BMIM)(Cl)), and followed by the anion exchange reaction, where the chloride anion is exchanged with hydroquinone sulfonate. The resulting product was characterized by 1H NMR, 13C NMR, FT-IR spectroscopy, themogravimetric analysis, and differential scanning calorimetry, and shows a high stability up to 340 °C. Its electrochemical behavior was investigated using cyclic voltammetry at different temperatures and its viscosity analysis was also performed at variable temperatures. The electrochemical response of the presented RAIL was found to be temperature dependent and diffusion controlled. Overall, our results demonstrated that (BMIM)(mix of HQS and HSQ) is redox active and possesses high stability and low volatility, leading to the employment of this RAIL without any additional supporting electrolyte or additives. 相似文献
108.
Anton A. Muravev Svetlana E. Solovieva Farida B. Galieva Olga B. Bazanova Ildar Kh. Rizvanov Kamil A. Ivshin Olga
N. Kataeva Susan E. Matthews Igor S. Antipin 《RSC advances》2018,8(57):32765
Late stage diversification of calix[4]arenes and thiacalix[4]arenes with heterocycles remains a significant synthetic challenge and hampers further exploitation of the scaffolds. Here we describe the development of a short and facile synthetic route to conformationally diverse novel calix[4]arene and thiacalix[4]arene ynones using a palladium cross coupling approach (5% Pd(ii) + 10% Cu(i)) with benzoyl chloride. Their successful conversion to heterocycles to afford pyrazoles was demonstrated through treatment with hydrazine. Functionalisation is calixarene conformation and linker independent enabling access to a library of structures.Late stage diversification of calix[4]arenes and thiacalix[4]arenes with heterocycles remains a significant synthetic challenge and hampers further exploitation of the scaffolds. 相似文献
109.
Recognition of coincidence of cerebral vascular disease is of importance in patients with coronary artery disease. One hundred and seventy-three patients who underwent coronary angiography were also studied by angiography of subclavian arteries and abdominal aorta. The majority of the patients (128/173; 74%) were men. Risk factors of hypertension, diabetes, and hypercholesterolemia were present in a high percentage of patients. Disease of the proximal part of the vertebral artery was seen in 41.6% (72/173). Presence of vertebral artery disease was significantly correlated with diabetes (p = 0.02), renal artery stenosis (p = 0.003), coronary artery disease (p = 0.05), and iliac artery disease (p = 0.05). The proximal part of the vertebral artery was found to be affected in a high percentage (41.6%) of patients undergoing coronary angiography. 相似文献
110.