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排序方式: 共有3697条查询结果,搜索用时 15 毫秒
71.
Roos M Lutz J Salmhofer H Luppa P Knauss A Braun S Martinof S Schömig A Heemann U Kastrati A Hausleiter J 《Clinical endocrinology》2008,68(4):660-665
Objective To examine the correlation of plasma fibroblast growth factor (FGF)‐23 and serum fetuin A levels with the coronary artery calcification score (CACS) in patients with normal kidney function. Background Vascular calcification is an active process that may be aggravated by hyperphosphataemia and hypercalcaemia. FGF‐23 and human fetuin‐A have been associated with calcifying arteriosclerosis in renal failure. Plasma FGF‐23 was identified as an independent factor negatively associated with peripheral vascular calcification. Fetuin‐A acts as a systemic inhibitor of ectopic calcification in dialysis patients and can be correlated to the survival of these patients. Very few data exists on the role of FGF‐23 and fetuin‐A in coronary calcification of patients without impaired kidney function. Materials and methods Sixty‐four patients, 21 females and 43 males, were subjected to 64‐slice coronary computed tomography (CT) to evaluate coronary artery calcification (CAC). Plasma intact FGF‐23 was determined by ELISA. Serum fetuin‐A concentration were evaluated nephelometrically. Results Mean plasma FGF‐23 level was 20·4 ± 9·1 pg/ml and serum fetuin‐A was 0·46 ± 0·09 g/l. There was no correlation between FGF‐23 (P = 0·777) and fetuin‐A (P = 0·767) levels and the CACS. No correlation was found between the presence of noncalcified plaques and coronary artery stenosis (CAS) ≥ 50%, and FGF‐23 (P = 0·313 and P = 0·775) and fetuin‐A levels (P = 0·601 and P = 0·659). Conclusion Plasma intact FGF‐23 and serum fetuin‐A concentration do not correlate with the CACS, the grade of stenosis or presence of noncalcified plaques of the coronary arteries in patients with normal kidney function. 相似文献
72.
BACKGROUND: Patent foramen ovale (PFO) with or without atrial septal aneurysm (ASA) is highly associated with cerebral ischemic events in young patients. The prevalence of PFO and ASA in elderly patients with cerebral ischemic events is not well described. OBJECTIVE: Our study is to evaluate the frequencies of PFO with right-to-left shunt (RLS) and ASA in elderly patients and to determine whether age is a predictor of flow-reversed PFO with RLS in cerebral ischemic events. METHODS: A prospective registry for all consecutive patients with cerebral ischemic events who were evaluated by transesophageal echocardiography (TEE) for the detection of possible cardiac source of embolization was established and maintained in a university hospital. Patients' demographics including age, gender, ethnic origin, cerebrovascular risk factors, and all positive TEE data were collected from July 2000 to August 2001 for statistical analysis. A univariate and multivariate stepwise logistic regression analysis was performed. RESULTS: In older patients the prevalence of PFO with RLS, PFO, and ASA was 25/118 (20%), 28/118 (24%), and 38/118 (32%), respectively, as opposed to younger patients, in whom it was 35/119 (30%), 39/119 (33%), and 38/119 (32%), respectively. Older patients had higher frequencies of hypertension (59; 69%), CAD (25; 21%), and prior history of stroke (23; 20%) as opposed to younger patients. Younger age (<60 years), gender, smoking history, hypertension, hyperlipidemia, CAD, and prior history of stroke were not associated with higher prevalence of PFO with RLS. Patent foramen ovale was associated with ASA (P < 0.001) and LVH (P < 0.019) in patients with TIA and stroke. In multivariate analysis only ASA (P < 0.001) remained significant with PFO, with RLS controlling for age, gender, and LVH. CONCLUSIONS: PFO with RLS and ASA are frequently present in elderly stroke and/or TIA patients and age is not a predictor for PFO. Transesophageal echocardiography should be considered for all stroke and/or TIA patients irrespective of their age. 相似文献
73.
Halimatus Sakdiah Minhat Hazwan Mat Din Raja Nurzatul Efah Raja Adnan 《International Journal of Mental Health Promotion, The》2021,23(3):409-416
Population ageing puts pressure on the workforce and increase the demands for aged workforce. The demographic shifts have made the issue of healthier workers, especially those of advanced age and physically related
job scopes, a fundamental aspect to employing older workers. Hence, this study aimed to explore the best practices to employ older adults into the social care sector. The social care sector was chosen in view of the nature of
job and declining demand among younger workers. A qualitative study was conducted involving series of focus
group discussions (FGD) with social care workers of long-term care centers in the peninsular Malaysia. Data was
collected using a validated and pre-tested semi-structured interview protocol. Each focus group discussions and
in-depth interviews were lasted between 45 min to 1 h. A total of 57 workers were consented for the study which
was divided into young and old workers based on the mean age of 41.43 [SD ± 9.97] years old. The content of the
interviews was transcribed verbatim and thematic analysis was performed to inductively identify the coding and
themes within the data related to the challenges employing older workers into the social care sector. Three categories of coding were identified (individual, environmental and management factors), leading to the identification
of two important themes which are healthy workplace and work autonomy. The findings indicate the needs for
work culture transformations to cultivate healthy working environment and freedom of speech particularly
among the older workers. 相似文献
74.
75.
Mariacristina Scoto Thomas Cullup Sebahattin Cirak Shu Yau Adnan Y Manzur Lucy Feng Thomas S Jacques Glenn Anderson Stephen Abbs Caroline Sewry Heinz Jungbluth Francesco Muntoni 《European journal of human genetics : EJHG》2013,21(11):1249-1252
Recessive nebulin (NEB) mutations are a common cause of nemaline myopathy (NM), typically characterized by generalized weakness of early-onset and nemaline rods on muscle biopsy. Exceptional adult cases with additional cores and an isolated distal weakness have been reported. The large NEB gene with 183 exons has been an obstacle for the genetic work-up. Here we report a childhood-onset case with distal weakness and a core-rod myopathy, associated with recessive NEB mutations identified by next generation sequencing (NGS). This 6-year-old boy presented with a history of gross-motor difficulties following a normal early development. He had distal leg weakness with bilateral foot drop, as well as axial muscle weakness, scoliosis and spinal rigidity; additionally he required nocturnal respiratory support. Muscle magnetic resonance (MR) imaging showed distal involvement in the medial and anterior compartment of the lower leg. A muscle biopsy featured both rods and cores. Initial targeted testing identified a heterozygous Nebulin exon 55 deletion. Further analysis using NGS revealed a frameshifting 4 bp duplication, c.24372_24375dup (P.Val8126fs), on the opposite allele. This case illustrates that NEB mutations can cause childhood onset distal NM, with additional cores on muscle biopsy and proves the diagnostic utility of NGS for myopathies, particularly when large genes are implicated. 相似文献
76.
Haiyan Zhou Ori Rokach Lucy Feng Iulia Munteanu Kamel Mamchaoui Jo M. Wilmshurst Caroline Sewry Adnan Y. Manzur Komala Pillay Vincent Mouly Michael Duchen Heinz Jungbluth Susan Treves Francesco Muntoni 《Human mutation》2013,34(7):986-996
In skeletal muscle, excitation–contraction (EC) coupling is the process whereby the voltage‐gated dihydropyridine receptor (DHPR) located on the transverse tubules activates calcium release from the sarcoplasmic reticulum by activating ryanodine receptor (RyR1) Ca2+ channels located on the terminal cisternae. This subcellular membrane specialization is necessary for proper intracellular signaling and any alterations in its architecture may lead to neuromuscular disorders. In this study, we present evidence that patients with recessive RYR1‐related congenital myopathies due to primary RyR1 deficiency also exhibit downregulation of the alfa 1 subunit of the DHPR and show disruption of the spatial organization of the EC coupling machinery. We created a cellular RyR1 knockdown model using immortalized human myoblasts transfected with RyR1 siRNA and confirm that knocking down RyR1 concomitantly downregulates not only the DHPR but also the expression of other proteins involved in EC coupling. Unexpectedly, this was paralleled by the upregulation of inositol‐1,4,5‐triphosphate receptors; functionally however, upregulation of the latter Ca2+ channels did not compensate for the lack of RyR1‐mediated Ca2+ release. These results indicate that in some patients, RyR1 deficiency concomitantly alters the expression pattern of several proteins involved in calcium homeostasis and that this may influence the manifestation of these diseases. 相似文献
77.
Fazal E. Subhan Aimal Daud Khan Adnan Daud Khan Najeeb Ullah Muhammad Imran Muhammad Noman 《RSC advances》2020,10(45):26631
Tandem configuration-containing perovskite and silicon solar cells are promising candidates for realizing a high power conversion efficiency of 30% at reasonable costs. Silicon solar cells with planar front surfaces used in tandem devices cause high optical losses, which significantly affects their efficiency. Moreover, some studies have explored the fabrication of perovskites on textured silicon cells. However, due to improper texturing, light trapping is not ideal in these devices, which reduces the efficiency. In this work, we optimized the pyramid height of textured silicon cells and efficiently characterized them to achieve enhanced light trapping. Two different kinds of perovskites, namely, Cs0.17FA0.6Pb(Br0.17I0.7)3 and Cs0.25FA0.6Pb(Br0.20I0.7)3 with wide bandgaps were conformally deposited on textured silicon cells, and the performance of these flat and fully textured tandem devices was numerically analyzed. The thickness of each layer in the tandem cell was optimized in a way to ensure a perfect current match between the top perovskite and bottom silicon subcells. The results indicated that the textured tandem configuration enhances light absorption over a broad spectral range due to the optimized pyramid height compared to flat surfaces. Eventually, the photovoltaic parameters of the proposed tandem cell were compared with the already existing structures, and our design supports large values of open circuit voltage (Voc) = 1.78 V, short circuit current density (Jsc) = 20.09 mA cm−2, fill factor (FF) = 79.01%, and efficiency (η) = 28.20% compared to other kinds of tandem solar cells.Tandem configuration-containing perovskite and silicon solar cells are promising candidates for realizing a high power conversion efficiency of 30% at reasonable costs. 相似文献
78.
Saidjafarzoda Ilhom Adnan Mohammad Deepa Shukla John Grasso Brian G. Willis Ali K. Okyay Necmi Biyikli 《RSC advances》2020,10(46):27357
In this work, we have studied the role varying nitrogen plasma compositions play in the low-temperature plasma-assisted growth of indium nitride (InN) thin films. Films were deposited on Si (100) substrates using a plasma-enhanced atomic layer deposition (PE-ALD) reactor featuring a capacitively-coupled hollow-cathode plasma source. Trimethylindium (TMI) and variants of nitrogen plasma (N2-only, Ar/N2, and Ar/N2/H2) were used as the metal precursor and nitrogen co-reactant, respectively. In situ ellipsometry was employed to observe individual ligand exchange and plasma-assisted ligand removal events in real-time during the growth process. Only the samples grown under hydrogen-free nitrogen plasmas (Ar/N2 or N2-only) resulted in nearly stoichiometric single-phase crystalline hexagonal InN (h-InN) films at substrate temperatures higher than 200 °C under 100 W rf-plasma power. Varying the plasma gas composition by adding H2 led to rather drastic microstructural changes resulting in a cubic phase oxide (c-In2O3) film. Combining the in situ measured growth evolution with ex situ materials characterization, we propose a simplified model describing the possible surface reactions/groups during a unit PE-ALD cycle, which depicts the highly efficient oxygen incorporation in the presence of hydrogen radicals. Further structural, chemical, and optical characterization have been carried out on the optimal InN films grown with Ar/N2 plasma to extract film properties. Samples grown at lower substrate temperature (160 °C) and reduced/elevated rf-plasma power levels (50/150 W) displayed similar amorphous character, which is attributed to either insufficient surface energy or plasma-induced crystal damage. InN samples grown at 240 °C under 100 W rf-plasma showed clear polycrystalline h-InN layers with ∼20 nm average-sized single crystal domains exhibiting hexagonal symmetry.Hollow-cathode plasma-generated hydrogen radicals induce crystal phase transformation from h-InN to c-In2O3 during plasma-enhanced atomic layer deposition using trimethyl-indium and Ar/N2 plasma. 相似文献
79.
Usman Arshad Adnan Mujahid Peter Lieberzeit Adeel Afzal Sadia Zafar Bajwa Naseer Iqbal Sumaira Roshan 《RSC advances》2020,10(57):34355
Monitoring antimalarial drugs is necessary for clinical assays, human health, and routine quality control practices in pharmaceutical industries. Herein, we present the development of sensor coatings based on molecularly imprinted polymers (MIPs) combined with quartz crystal microbalance (QCM) for sensitive and selective gravimetric detection of an antimalarial drug: artemether. The MIP coatings are synthesized by using artemether as the template in a poly(methacrylic acid-co-ethylene glycol dimethacrylate) matrix. Artemether-MIP and the non-imprinted polymer (NIP) control or reference layers are deposited on 10 MHz dual-electrode QCM by spin coating (187 ± 9 nm layer thickness after optimization). The coatings are characterized by FTIR spectroscopy and atomic force microscopy that reveal marked differences among the MIP and NIP. The MIP-QCM sensor exhibits high sensitivity (0.51 Hz ppm−1) with sub-10 ppm detection and quantification limits. The MIP-QCM sensor also exhibits a 6-fold higher sensitivity compared to the NIP-QCM, and a dynamic working range of 30–100 ppm. The response time of MIP-QCM devices for a single cycle of analyte adsorption, signal saturation, and MIP regeneration is less than 2.5 min. The sensor also demonstrates selectivity factors of artemether-MIP of 2.2 and 4.1 compared to artemisinin and lumefantrine, respectively. Reversibility tests reveal less than 5% variation in sensor responses over three cycles of measurements at each tested concentration. The MIP-QCM showed lower detection limits than conventional HPLC-UV, and faster response time compared to HPLC-UV and liquid chromatography-mass spectrometry (LC-MS).Chemical structures of the antimalarial drugs: artemisinin, artemether (a methyl ether derivative of artemisinin), and lumefantrine. 相似文献
80.
Malvi Surti Mitesh Patel Mohd Adnan Afrasim Moin Syed Amir Ashraf Arif Jamal Siddiqui Mejdi Snoussi Sumukh Deshpande Mandadi Narsimha Reddy 《RSC advances》2020,10(62):37707
The outbreak of novel coronavirus, SARS-CoV-2, has infected more than 36 million people and caused approximately 1 million deaths around the globe as of 9 October 2020. The escalating outspread of the virus and rapid rise in the number of cases require the instantaneous development of effectual drugs and vaccines. Presently, there are no approved drugs or vaccine available to treat the infection. In such scenario, one of the propitious therapeutic approaches against viral infection is to explore enzyme inhibitors amidst natural compounds, utilizing computational approaches aiming to get products with negligible side effects. In the present study, the inhibitory prospects of ilimaquinone (marine sponge metabolite) were assessed in comparison with hydroxychloroquine, azithromycin, favipiravir, ivermectin and remdesivir at the active binding pockets of nine different vital SARS-CoV-2 target proteins (spike receptor binding domain, RNA-dependent RNA polymerase, Nsp10, Nsp13, Nsp14, Nsp15, Nsp16, main protease, and papain-like-protease), employing an in silico molecular interaction based approach. In addition, molecular dynamics (MD) simulations of the SARS-CoV-2 papain-like protease (PLpro)–ilimaquinone complex were also carried out to calculate various structural parameters including root mean square fluctuation (RMSF), root mean square deviation (RMSD), radius of gyration (Rg) and hydrogen bond interactions. PLpro is a promising drug target, due to its imperative role in viral replication and additional function of stripping ubiquitin and interferon-stimulated gene 15 (ISG15) from host-cell proteins. In light of the possible inhibition of all vital SARS-CoV-2 target proteins, our study has emphasized the importance to study in depth ilimaquinone actions in vivo.Inhibitory potential of ilimaquinone (marine sponge metabolite) against nine essential SARS-CoV-2 target proteins, employing a molecular interaction and dynamics simulation approach. 相似文献