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101.
Rajiv Gandhi David Wasserstein Fahad Razak J. Roderick Davey Nizar N. Mahomed 《Obesity (Silver Spring, Md.)》2010,18(12):2362-2366
Obesity has been identified as a risk factor for the development of hip and knee osteoarthritis (OA) and may play a role in exacerbating existing disease. Therefore, we hypothesized that obese patients would present for hip and knee replacement surgery at a younger age than nonobese patients. From our registry, we performed a cross‐sectional study of 841 hip and 804 knee replacement patients. Patients were categorized by BMI ≤25 kg/m2, 25.1–29.9 kg/m2, 30–34.9 kg/m2, and ≥35 kg/m2. Linear regression modeling was used to examine the relationship between BMI and age at surgery. Hip and knee replacement patients' mean age at surgery was 7.1 and 7.9 years younger, respectively, if their BMI was ≥35 kg/m2 when compared to patients with a BMI ≤25 kg/m2 (P = 0.002). BMI was a significant independent (of gender, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, surgeon, and comorbidity) predictor of age at knee replacement (P < 0.05). WOMAC scores were significantly worse preoperatively in patients with a BMI ≥35 kg/m2 compared to those with a BMI ≤25 kg/m2 (P < 0.05). Our study indicates that obese patients, especially those with a BMI ≥35 kg/m2, presented for and underwent joint replacement surgery at a younger age as compared to nonobese patients. 相似文献
102.
Rajiv Kumar Vikas Sharma Silvia Bua 《Journal of enzyme inhibition and medicinal chemistry》2017,32(1):1187-1194
A library of benzenesulphonamides incorporating 1,2,3-triazole rings functionalised with ester, carboxylic acid, carboxamide, carboxyhydrazide, and hydroxymethyl moieties were synthesised. The carbonic anhydrase (CAs, EC 4.2.1.1) inhibitory activity of the new compounds was assessed against four human (h) isoforms, hCA I, hCA II, hCA IV, and hCA IX. Among them, hCA II and IV are anti-glaucoma drug targets, being involved in aqueous humour secretion within the eye. hCA I was inhibited with Ki’s ranging between 8.3?nM and 0.8737?µM. hCA II, the physiologically dominant cytosolic isoform, was excellently inhibited by these compounds, with Ki’s in the range of 1.6–9.4?nM, whereas hCA IV was effectively inhibited by most of them, with Ki’s in the range of 1.4–55.3?nM. Thirteen of the twenty sulphonamides were found to be excellent inhibitors of tumour associated hCA IX with Ki’s?≤?9.5?nM. Many of the new compounds reported here showed low nM inhibitory action against hCA II, IV, and IX, isoforms involved in glaucoma and some tumours, making them interesting candidates for further medicinal chemistry/pharmacologic studies. 相似文献
103.
Lasing transition at 1.06 μm emission in Nd3+‐doped borate‐based tellurium calcium zinc niobium oxide glasses for high‐power solid‐state lasers
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O. Ravi K. Prasad Rajiv Jain M. Venkataswamy Shivanand Chaurasia B. Deva Prasad Raju 《Luminescence》2017,32(5):688-694
The spectroscopic properties of Tellurium Calcium Zinc Niobium oxide Borate (TCZNB) glasses of composition (in mol%) 10TeO2 + 15CaO + 5ZnO + 10 Nb2O5 + (60 – x)B2O3 + Nd2O3 (x = 0.1, 0.5, 1.0 or 1.5 mol%) have been investigated experimentally. The three phenomenological intensity parameters Ω2, Ω4, Ω6 have been calculated using the Judd–Ofelt theory and in turn radiative properties such as radiative transition probabilities, emission cross‐sections, branching ratios and radiative lifetimes have been estimated. The trend found in the JO intensity parameter is Ω2 > Ω6 > Ω4 If Ω6 > Ω4, the glass system is favourable for the laser emission 4F3/2 → 4I11/2 in the infrared (IR) wavelength. The experimental values of branching ratio of 4F3/2 → 4I11/2 transition indicate favourable lasing action with low threshold power. The evaluated total radiative transition probabilities (AT), stimulated emission cross‐section (σe) and gain bandwidth parameters (σe × Δλp) were compared with earlier reports. An energy level analysis has been carried out considering the experimental energy positions of the absorption and emission bands. 相似文献
104.
105.
Annamária Nádor Rajiv Sinha Árpád Magyari Sampat K. Tandon Zsófia Medzihradszky Edit Babinszki Edit Thamó-Bozsó Zoltán Unger Ashish Singh 《Palaeogeography, Palaeoclimatology, Palaeoecology》2011,299(1-2):1-14
Four drill cores and a clay pit section have been examined in the southern part of the Körös plain to understand the history and controls on alluvial sedimentation for the last ~ 40 ka. Four facies groups were identified, such as channel, channel margin, floodplain and floodbasin with seven distinctive facies. Magnetic susceptibility and mineralogy have further characterized the sedimentary facies indicating shifts in humidity conditions, variations in sediment flux and pedogenesis. Detailed pollen analysis of a 7.5 m thick clayey succession indicated climatic variability within the MIS 3 period. The spatial distribution of the different facies allowed outlining alluvial architecture of the study area. Three depositional units composed of various facies were identified based on OSL and radiocarbon data. These packages correspond to three major phases of channel activity: (F-I) pre-LGM period (> 30 ka to 24 ka), (F-II) post-LGM interstadial (18–16 ka), and (F-III) Late Glacial < 15 ka to ~ 10 ka). The pre-LGM and post-LGM “interstadial” phases are characterized by meandering river patterns, while the Late Glacial fluvial activity is characterized by a braided system in the area. Higher sediment supply feeding this braided river was probably caused by neotectonic uplift of the southern margin of the basin, documented by a significant stratigraphic gap between 25 and 14 ka. 相似文献
106.
Liver failure: basis of benefit of therapy with the molecular adsorbents recirculating system 总被引:6,自引:0,他引:6
Sen S Jalan R Williams R 《The international journal of biochemistry & cell biology》2003,35(9):1306-1311
Accumulation of albumin-bound toxins is known to occur in liver failure, and to variable extents is responsible for the associated end-organ dysfunctions (kidney, circulation, brain). The toxin-binding and scavenging functions of albumin are exploited in albumin dialysis for removal of these toxins. The extracorporeal liver support device known as molecular adsorbents recirculating system (MARS) is based on dialysis across an albumin-impregnated membrane, using 20% albumin as dialysate. Charcoal and anion exchange resin columns in the circuit help cleanse and regenerate the dialysate. Clinical studies over the last few years have demonstrated proven reduction in hyperbilirubinaemia, along with an improvement in encephalopathy, systemic haemodynamics and renal function in liver failure patients, as well as apparent improvement in survival. The results of larger controlled clinical trials, as well as studies investigating the pathophysiological basis of its effect, are awaited. 相似文献
107.
Rajiv C. McCoy Nandita R. Garud Joanna L. Kelley Carol L. Boggs Dmitri A. Petrov 《Molecular ecology》2014,23(1):136-150
The analysis of molecular data from natural populations has allowed researchers to answer diverse ecological questions that were previously intractable. In particular, ecologists are often interested in the demographic history of populations, information that is rarely available from historical records. Methods have been developed to infer demographic parameters from genomic data, but it is not well understood how inferred parameters compare to true population history or depend on aspects of experimental design. Here, we present and evaluate a method of SNP discovery using RNA sequencing and demographic inference using the program δaδi, which uses a diffusion approximation to the allele frequency spectrum to fit demographic models. We test these methods in a population of the checkerspot butterfly Euphydryas gillettii. This population was intentionally introduced to Gothic, Colorado in 1977 and has as experienced extreme fluctuations including bottlenecks of fewer than 25 adults, as documented by nearly annual field surveys. Using RNA sequencing of eight individuals from Colorado and eight individuals from a native population in Wyoming, we generate the first genomic resources for this system. While demographic inference is commonly used to examine ancient demography, our study demonstrates that our inexpensive, all‐in‐one approach to marker discovery and genotyping provides sufficient data to accurately infer the timing of a recent bottleneck. This demographic scenario is relevant for many species of conservation concern, few of which have sequenced genomes. Our results are remarkably insensitive to sample size or number of genomic markers, which has important implications for applying this method to other nonmodel systems. 相似文献
108.
109.
Daniela Cretu Ioannis Prassas Punit Saraon Ihor Batruch Rajiv Gandhi Eleftherios P Diamandis Vinod Chandran 《Clinical proteomics》2014,11(1):27
Background
Synovial fluid (SF) is a dynamic reservoir for proteins originating from the synovial membrane, cartilage, and plasma, and may therefore reflect the pathophysiological conditions that give rise to arthritis. Our goal was to identify and quantify protein mediators of psoriatic arthritis (PsA) in SF.Methods
Age and gender-matched pooled SF samples from 10 PsA and 10 controls [early osteoarthritis (OA)], were subjected to label-free quantitative proteomics using liquid chromatography coupled to mass spectrometry (LC-MS/MS), to identify differentially expressed proteins based on the ratios of the extracted ion current of each protein between the two groups. Pathway analysis and public database searches were conducted to ensure these proteins held relevance to PsA. Multiplexed selected reaction monitoring (SRM) assays were then utilized to confirm the elevated proteins in the discovery samples and in an independent set of samples from patients with PsA and controls.Results
We determined that 137 proteins were differentially expressed between PsA and control SF, and 44 were upregulated. The pathways associated with these proteins were acute-phase response signalling, granulocyte adhesion and diapedesis, and production of nitric oxide and reactive oxygen species in macrophages. The expression of 12 proteins was subsequently quantified using SRM assays.Conclusions
Our in-depth proteomic analysis of the PSA SF proteome identified 12 proteins which were significantly elevated in PsA SF compared to early OA SF. These proteins may be linked to the pathogenesis of PsA, as well serve as putative biomarkers and/or therapeutic targets for this disease. 相似文献110.