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131.
Merve Kl Aysel
zpnar Mustafa Serteser Meltem Kilercik Muhittin Serdar 《Journal of Medical Biochemistry》2022,41(1):1
BackgroundIron deficiency anemia (IDA) is the most common type of anemia worldwide and has many adverse effects on life quality. This meta-analysis study aims to show that reticulocyte hemoglobin content (CHr) is more effective than routinely used parameters in the diagnosis of IDA.MethodsComprehensive and systematic research was done using international databases including PubMed, Web of Science, Cochrane Library, Science Direct, and Google Scholar, which contain all articles published on IDA until December 29, 2020. Seventeen articles were included in the meta-analysis.ResultsThe analyses found the Cohen''s deffect size (Standardized Mean Difference) values of the parameters. Accordingly, CHr is 2.84 (95% CI 2.36 to 3.31), mean corpus volume (MCV) is 2.46 (95% CI 1.97 to 2.95), ferritin is 2.37 (95% CI 1.63 to 3.11), and transferrin saturation (TSAT) is 3.76 (95% CI 2.14 to 5.38). To diagnose IDA, the sensitivity value of the CHr concentration was found as 83.5% (95% CI 76.1 to 89.8), specificity value to be 91.8% (95% CI 85.5 to 96.4), and mean cut-off value as 28.2 pg.ConclusionsThe results of our study reveal the findings that CHr is a better biomarker than MCV and ferritin used in determining IDA, and its efficacy is lower than TSAT. It is very important to use it routinely for the pre-diagnosis of IDA, which is very important for public health. The groups in the study are heterogeneous but contain bias. Therefore, meta-analyses of studies with less heterogeneity of CHr are needed. 相似文献
132.
Hande Karpuzoglu Yasemin Ucal Pinar Kumru Murat Muhcu Mustafa Eroglu Muhittin Serdar Mustafa Serteser Aysel Ozpinar 《Journal of Medical Biochemistry》2022,41(2):156
BackgroundSeveral factors may influence newborn thyroid-stimulating hormone (TSH) concentrations and cause subclinical hypothyroidism in a newborn. A sufficient level of leptin signalling is needed for the normal production of TSH and thyroid hormones by the thyroid gland. Our study aimed to investigate the correlation between maternal serum leptin concentration during the third trimester of pregnancy and newborn screening-TSH levels.MethodsThis prospective cross-sectional study was conducted in obstetrics and gynaecology clinics of a state hospital between June and August 2013. Maternal venous blood samples were collected from 270 healthy pregnant women in the third trimester just before delivery. Measurements of maternal fT3, fT4, TSH, anti-thyroid peroxidase (TPO), and anti-thyroglobulin (anti-Tg) antibodies from serum samples were performed by chemiluminescence immunoassay. Maternal serum leptin levels were determined by ELISA. Dried capillary blood spots were used to measure newborn TSH levels.ResultsSubjects were divided into two groups according to the neonatal TSH levels using a cut-point of 5.5 mIU/L. Median maternal serum leptin levels were significantly higher in newborns whose TSH levels were higher than >5.5 mIU/L [13.2 μg/L (1.3 - 46.5) vs 19.7 μg/L (2.4 - 48.5), p<0.05]. Serum leptin levels showed a negative correlation with maternal fT4 (r=0.32, p<0.05), fT3 (r=0.23, p<0.05), and a positive correlation with BMI (r=0.30, p<0.05).ConclusionsOur results suggest that high leptin levels in the third trimester of pregnancy influence maternal thyroid functions and might cause an increase in newborn TSH levels. Detection of high maternal serum leptin levels may be a reason for subclinical hypothyroidism. 相似文献
133.
134.
When plasma proteins leak from circulation into the renal tubular lumen in the proteinuric renal diseases, nephrotoxicity of filtered albumin (and/or molecules bound to it) may be important in the subsequent development of tubulo-interstitial damage which contributes to the progression of the disease. When cultured opossum kidney (OK) proximal tubular cells were exposed to bovine serum albumin for 3 days in vitro, increased cell division ([3H]-thymidine incorporation) and cellular hypertrophy (increased protein/DNA ratio) were observed. Both effects were halved if defatted albumin was used. A trivial explanation for the growth responses is that free fatty acids carried on the albumin, and amino acids generated by intracellular degradation of the albumin, are exerting a non-specific growth effect as metabolic fuels which are oxidized to generate ATP. However, the water-soluble free fatty acid octanoate (1 mmol l(-1)) had no significant effect on protein/DNA ratio and a very variable stimulatory effect on [3H]-thymidine incorporation, whereas an essential amino acid mixture or 1 mmol/l(-1) l-Ala or l-Phe only increased the protein/DNA ratio. Furthermore no carnitine was added to the culture medium. This absence would have impaired mitochondrial transport (and hence oxidation) of long-chain free fatty acids derived from the albumin. l-Phe is also a poor substrate for mitochondrial oxidation in kidney. It is therefore concluded that the growth effects of albumin in OK proximal tubular cells are specific effects of the albumin protein and of the free fatty acids and amino acids derived from it, and not a non-specific effect on metabolic fuel supply. 相似文献
135.
136.
Immunocompetent mice 129Sv (129) and C57BL/6 (B6) mice are similarly susceptible to Anaplasma phagocytophilum. We now show that 129 mice lacking interferon-gamma (IFN-gamma) develop more severe infection with A. phagocytophilum than IFN-gamma deficient B6 mice. These data demonstrate that there is an inherent increased susceptibility of 129 mice, compared with B6 mice, to A. phagocytophilum that can only be discerned in the absence of IFN-gamma. 相似文献
137.
Küpeli E Aslan M Gürbüz I Yesilada E 《Zeitschrift für Naturforschung. C, Journal of biosciences》2004,59(11-12):787-790
Anti-nociceptive, anti-inflammatory and gastroprotective activities of the known C-glycosyl flavonoid, isoorientin, were studied in rats and mice. For the anti-nociceptive activity assessment the p-benzoquinone-induced writing test, for the anti-inflammatory activity the carrageenan-induced hind paw edema model in mice, and for the gastroprotective activity the EtOH-induced ulcerogenesis model in rats were used. Isoorientin was shown to possess significant anti-nociceptive and anti-inflammatory activities at 15 mg/kg and 30 mg/kg doses, without inducing any apparent acute toxicity as well as gastric damage. However, the compound did not possess any significant gastroprotective activity against EtOH-induced ulcerogenesis. 相似文献
138.
Yilmaz HR Songur A Ozyurt B Zararsiz I Sarsilmaz M 《Prostaglandins, leukotrienes, and essential fatty acids》2004,71(2):131-135
In this experimental study, the effect of fish n-3 fatty acids was studied on the some important enzymes of carbohydrate metabolism, hexokinase (HK), glucose-6-phosphate dehydrogenase (G6PD), 6-phosphogluconate dehydrogenase (6PGD), lactate dehydrogenase (LDH), and malate dehydrogenase (MDH) in rat liver. Wistar albino rats of experimental group (n= 9) were supplemented fish omega-3 fatty acids (n-3 PUFA) as 0.4 g/kg bw. by gavage for 30 days in addition to their normal diet. Isotonic solution was given to the control group (n= 8) by the same way. At 30th day, the rats were killed by decapitation under ether anesthesia, autopsied and liver was removed. Spectrophotometric methods were used to determine the activities of above-mentioned enzymes in the liver. The n-3 PUFA caused increases in the activities of HK, G6PD, LDH, and MDH in comparison with control. These increases were statistically significant (P < 0.01) except 6PGD activity. As a result, n-3 PUFA may regulate the metabolic function of liver effectively by increasing HK, G6PD, 6PGD, LDH, and MDH enzyme activities of rat liver when added in enough amounts to the regular diet. 相似文献
139.
A biosensor based on mushroom tissue homogenate for detecting some phenolic compounds (PCs) and usage of the biosensor for quantifying certain substances that inhibit the polyphenol oxidase activity in mushroom (Agaricus bisporus) tissue homogenate is described. The mushroom tissue homogenate was immobilized to the top of a Clark-type oxygen electrode with gelatin and glutaraldehyde. Optimization of the experimental parameters was done by buffer system, pH, buffer concentration, and temperature. Besides, the detection range of eight phenolic compounds were obtained with the help of the calibration graphs. Thermal stability, storage stability, and repeatability of the biosensor were also investigated. A linear response was observed from 20 x 10(-3) to 200 x 10(-3) mM phenol. The biosensor retained approximately 74% of its original activity after 25 days of storage at 4 degrees C. In repeatability studies, variation coefficient (C.V.) and standard deviation (S.D.) were calculated as 2.44% and +/-0.002, respectively. Inhibition studies revealed that the proposed biosensor was applicable for monitoring benzoic acid and thiourea in soft drinks and fruit juices. 相似文献
140.
Chung CS Karamanoglu M Kovács SJ 《American journal of physiology. Heart and circulatory physiology》2004,287(5):H2003-H2008
The duration of diastole can be defined in terms of mechanical events. Mechanical diastolic duration (MDD) is comprised by the phases of early rapid filling (E wave), diastasis, and late atrial filling (A wave). The effect of heart rate (HR) on diastolic duration is predictable from kinematic modeling and known cellular physiology. To determine the dependence of MDD of each phase and the velocity time integral (VTI) on HR, simultaneous transmitral Doppler flow velocities and ECG were recorded during supine bicycle exercise in healthy volunteers. Durations, peak values, and VTI using triangular approximation for E- and A-wave shape were measured. MDD, defined as the interval from the start of the E wave to end of the A wave, was fit as an algebraic function of HR by MDD=BMDD + MLMDD.HR + MIMDD/HR, derivable from first principles, where BMDD is a constant, and MLMDD and MIMDD are the constant coefficients of the linear and inverse HR dependent terms. Excellent correlation was observed (r2=0.98). E- and A-wave durations were found to be very nearly independent of HR: 100% increase in HR generated only an 18% decrease in E-wave duration and 16% decrease in A-wave duration. VTI was similarly very nearly independent of HR. Diastasis duration closely tracked MDD as a function of HR. We conclude that the elimination of diastasis and merging of E and A waves of nearly fixed durations primarily govern changes in MDD. These observations support the perspective that E- and A-wave durations are primarily governed by the rules of mechanical oscillation that are minimally HR dependent. 相似文献