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81.
82.
A 50 year old male was admitted in our hospital with anemia and impaired renal function. He was subsequently found to have extremely elevated serum phosphate level (24 mg/dL, reference interval: 2.5–4.5 mg/dL) with normal serum calcium when assayed on a Beckman Coulter AU 480® analyser. Clinico-biochemical discrepancy led to the suspicion of spurious hyperphosphatemia. Serum total protein was grossly elevated with gross reversal of albumin to globulin ratio. Serum electrophoresis revealed a large M band and was confirmed as Ig G-Kappa type on immunofixation. Subsequently a bone marrow aspiration biopsy confirmed the diagnosis of multiple myeloma. The patient serum was then reassayed for phosphate on a Vitros® 250 Dry Chemistry platform and the result was within normal reference interval. Paraproteinemias are a common cause of analytical interference in clinical biochemistry laboratories and as multilayered film technology platforms like Vitros® assay most routine analytes on a protein free filtrate they are unaffected by paraprotein interference. Clinically discordant patient results should always be interpreted keeping such interferences in mind.  相似文献   
83.
An on-chip lectin microarray based glycomic approach is employed to identify glyco markers for different gastritis and gastric cancer. Changes in protein glycosylation have impact on biological function and carcinogenesis. These altered glycosylation patterns in serum proteins and membrane proteins of tumor cells can be unique markers of cancer progression and hence have been exploited to diagnose various stages of cancer through lectin microarray technology. In the present work, we aimed to study the alteration of glycan structure itself in different stages of gastritis and gastric cancer thoroughly. In order to perform the study from both serum and tissue glycoproteins in an efficient and high-throughput manner, we indigenously developed and employed lectin microarray integrated on a microfluidic lab-on-a-chip platform. We analyzed serum and gastric biopsy samples from 8 normal, 15 chronic Type-B gastritis, 10 chronic Type-C gastritis, and 6 gastric adenocarcinoma patients and found that the glycoprofile obtained from tissue samples was more distinctive than that of the sera samples. We were able to establish signature glycoprofile for the three disease groups, that were absent in healthy normal individuals. In addition, our findings elucidated certain novel signature glycan expression in chronic gastritis and gastric cancer. In silico analysis showed that glycoprofile of chronic gastritis and gastric adenocarcinoma formed close clusters, confirming the previously hypothesized linkage between them. This signature can be explored further as gastric cancer marker to develop novel analytical tools and obtain in-depth understanding of the disease prognosis.  相似文献   
84.
Machining of micro holes with micro electro- chemical machining (micro ECM) process has been carried out with an indigenously developed set up. This paper describes relevant problems and solutions for the circular micro holes machining process on 304 stainless steel sheets with 60 μm thickness using high speed steel cylindrical tool of diameter 500 ~tm and using dilute I-I2SO4 as elec- trolyte. The taper angle variation of the machined hole is analyzed and reported for different experimental setting parameters. The minimum value of the taper angle of machined holes is achieved at the parameter setting of 0.4 mol/L H2504, 700 kHz, 600 ns and 21 V, for stainless steel sheets and HSS tool.  相似文献   
85.
A number of factors are linked with non-alcoholic fatty liver diseases (NAFLD), a condition that ranges from clinically benign fatty liver to its more severe form, non alcoholic steatohepatitis (NASH). In this study, we evaluated the role of cytokines secreted from adipose tissue in the pathogenesis and progression of NAFLD. We also compared anthropometric profile, lipid profile and insulin resistance data in 105 NAFLD patients with 77 normal subjects. These subjects showed a normal serum albumin level, prothrombin time and renal function but elevated aminotransferases. Predisposing factors were diabetes mellitus (35%), overweight (56%) and hyperlipidemia (44%). Insulin resistance (IR), determined by homeostasis model assessment (HOMA) was confirmed in 70% patients with NAFLD and 42% patients fulfilled the minimum criteria for insulin resistance syndrome (IRS). NAFLD patients showed elevated levels of pro-inflammatory cytokines tumor necrosis factor (TNF)-α, and interleukin (IL)-6, while anti-inflammatory cytokines IL-4 level decreased and IL-10 level remain unchanged; however, TGF-β1 level elevated significantly compared to normal subjects. While insulin level and HOMA-IR both were significantly positively correlated with BMI, waist-to-hip ratio, total cholesterol, VLDL-cholesterol, triglyceride and TGF-β1; glucose, IL-6 and TNF-α levels were significantly positively correlated with HOMA-IR only. In conclusion, pro-inflammatory cytokines play an important link between metabolic and liver disorders in the fat accumulation, and thereby cause IR, inflammation and liver fibrosis.  相似文献   
86.
A randomized case control hospital based study was conducted over 12 months time on 31 asphyxiated and 31 normal newborn to see whether urinary uric acid can be used as a marker of perinatal asphyxia and can be correlated with the clinical diagnosis by Apgar score. Uric acid and creatinine were estimated in spot urine within 24 hours after birth in both cases and controls. A ratio between concentrations of uric acid to creatinine was estimated and compared between cases and controls. It was found that the ratios were significantly higher in cases than controls (3.1± 1.3 vs 0.96± 0.54; P < 0.001) and among asphyxia patients, a significant negative linear correlation was found between the uric acid to creatinine ratio and the Apgar score (r = −0.857, P < 0.001). So urinary uric acid to creatinine ratio can be used as an additional non-invasive dispace, easy and at the same time early biochemical marker of birth asphyxia which biochemically supports the clinical diagnosis and severity grading of asphyxia by Apgar score.  相似文献   
87.
88.
TB as the cause of uveitis varies from 0.5 to 10.5%; low sensitivity of confirmatory laboratory investigations and inconsistency of diagnostic criteria leads to paucity of data. Diagnosis requires a high level of suspicion and is often presumptive based on indirect evidences. Interferon gamma, Interleukin-2 and Neopterin are key biomarkers in immuno-regulation of Mycobacterium tuberculosis infection. The relative shift from Interleukin-2 towards Interferon gamma (Interferon gamma/Interleukin-2) is more discriminatory for active tuberculosis. Protein carbonyl and Malondialdehyde, as oxidative stress markers, characterize active tuberculosis. A case of disseminated TB presenting with acute uveitis had a recurrent tubercular lymphadenitis after completing category I treatment under revised national tuberculosis control programme. The present study evaluates the potential utility of above mentioned biomarkers to predict atypical presentation in difficult cases of tuberculosis. Though tuberculous uveitis is amenable to treatment in early course of disease, the delay in diagnosis can have serious consequences for the patient.  相似文献   
89.
Low density lipoprotein (LDL) was isolated from normal rabbits and was modified with acetic anhydride. Blood monocyte derived macrophages from normal and hypercholesterolemic (HC) rabbits were cultured, and on the 8th day the cells were incubated with native and modified LDL to study their binding and degradation. Macrophages from both normal and hypercholesterolemic rabbits express a limited number of receptors for normal plasma LDL whereas they exhibit a large number of receptors for acetyl LDL. There was no significant difference between binding and degradation of acetyl LDL by normal or hypercholesterolemic cells. However, binding and degradation of native LDL by monocytes of hypercholesterolemic cells were significantly less (p<0.0001) in comparison to binding and degradation of native LDL by normal cells indicating that there is a feedback inhibitory pathway in the cell that inhibits the synthesis of LDL receptors in the presence of excess LDL.  相似文献   
90.
Simple and sensitive Liquid Chromatography-Tandem Mass Spectrometry (LCMS/MS) method was developed and validated, then was implicated on hypertensive human subjects to study drug interaction of atorvastatin (ATVS) and Olmesartan (OLM) on status of Angiotensin-II (ANG-II). The ANG-II in plasma was extracted with 5 mL methanol containing 5 % formic acid through C18 (cartridges) liquid–liquid extraction, dried and reconstituted with 1 mL of 16 % acetonitrile in 0.1 % formic acid in water. The chromatographic separation of ANG-II with a Agilent technology 6410 Triple quadrupole was carried multiple reaction monitoring scan mode with a Agilent 1290 Infinity LC system for UHPLC. The sample were separated on a (Thermo Scientific) Hy-Purity advance (50 × 4.6 mm, 5 μm) using Mobile Phase A: 16 % acetonitrile in 0.1 % formic acid in water and Mobile Phase B: 0.1 % formic acid in methanol at a flow rate of 0.3 mL/min, performed at ambient temperature. The mobile phase gradient of 16 % acetonitrile in water was linearly increased to 38 % acetonitrile over 10 min and subsequently the mobile-phase was increased to 100 % acetonitrile over 15 min. The developed method was validated for specificity, accuracy, precision, stability, linearity, sensitivity and recovery. The method was linear between peak area ratio of standard and internal standard over the range of 50–800 ng/mL. The method was successfully applied for the drug interaction study revealed levels of ANG-II were significantly higher in ATVS + OLM treatment condition as compared to individual treatment of OLM. This reflects the reason of low effectiveness of ATVS + OLM in combination instead of synergistic activity.

Electronic supplementary material

The online version of this article (doi:10.1007/s12291-014-0457-x) contains supplementary material, which is available to authorized users.  相似文献   
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