Maternal serum interlukin-6 level in preterm labor

Objective: The aim of this study was to measure interleukin-6 (IL-6) levels in maternal serum of women undergoing preterm labor without a clear infection. Materials and Methods: Twenty two pregnant women with diagnosis of preterm labor who presented to the outpatient clinic of 19 Mayıs University Faculty of Medicine from July 2011 through December 2011 were enrolled in the study group. Twenty two healthy pregnant women who were at the same gestational age as the study group were selected as the control group. Results: Gestational age in the study and control groups varied from 24 weeks and 4 days to 34 weeks and 6 days. In the study group, 11 patients (50%) underwent preterm birth. Pregnant women in preterm labor were compared to healthy pregnant women with regards to serum IL-6 levels. No significant difference was found in the IL-6 levels of maternal serum between the 2 groups. Conclusion: In this study, we have shown that there is no increase in IL-6 levels in patients undergoing preterm labor without clinical or biochemical infection signs

Hemoglobin is inversely related to flow-mediated dilatation in chronic kidney disease

The microcirculation is regulated by oxygen gradients and by endothelial release of nitric oxide, which can react with hemoglobin to form S-nitroso derivatives. Here we induced flow-mediated dilatation of the brachial artery in response to ischemia in 141 non-diabetic patients with stage 3–4 chronic kidney disease who had no history of smoking, cardiovascular events or use of erythropoietin-based agents. Patients with hemoglobin concentrations above the cohort median of 11.6 g/dl were found to have significant reductions in flow-mediated dilatation compared to those below the median. This inverse relationship remained significant after adjustment for potential confounders, including insulin sensitivity, glomerular filtration rate, proteinuria, body mass index, serum urate, etiology of underlying renal disease, treatment with anti-hypertensive drugs, and traditional Framingham risk factors. Given that hemoglobin can act as an important nitric oxide carrier and buffer, our studies suggest that the mechanism by which hemoglobin influences the endothelium-dependent microcirculation requires its nitrosylation; however, more direct studies need to be performed

FGF-23 and vascular dysfunction in patients with stage 3 and 4 chronic kidney disease

Studies in animals show that fibroblast growth factor (FGF)-23 interferes with vascular reactivity induced by the nitric oxide (NO) system. To investigate the relationship between circulating FGF-23 levels and the response of forearm blood flow to ischemia (flow-mediated vasodilatation, FMD) and nitroglycerin, we tested 183 patients with stage 3-4 chronic kidney disease (CKD). None of them had cardiovascular complications or were taking drugs interfering with vascular function. Patients with FGF-23 levels above the median had significantly lower glomerular filtration rate, FMD, and fetuin-A levels (an anti-inflammatory molecule and potent inhibitor of calcification). They also had higher proteinuria and phosphate levels when compared to patients whose FGF-23 levels were below the median. The response to nitroglycerin was not different between the two groups. Multiple regression analysis showed that the relationship between FGF-23 and FMD was only modestly sensitive to adjustment for classical risk factors, biomarkers of bone mineral metabolism, high-sensitivity C-reactive protein, and homeostatic model assessment index. Adjustment for asymmetrical dimethyl arginine (ADMA) weakened the strength of this link; however, it remained highly significant. There was no independent association between FGF-23 and nitroglycerin. Thus, attenuation of FMD by ADMA suggests that this endogenous inhibitor of NO synthase may, in part, mediate the vascular effects of FGF-23 in patients with CKD. © 2010 International Society of Nephrology

Endothelial function in patients with familial Mediterranean fever-related amyloidosis and association with cardiovascular events

Objectives. Secondary amyloidosis is the most important complication of FMF and endothelial function is more severely impaired. Elevated asymmetric dimethyl arginine (ADMA) may mediate the excess cardiovascular disease (CVD) risk of this group. We aimed to compare endothelial function characteristics, including ADMA, in patients with FMF-related amyloidosis and primary glomerulopathies and to define risk factors for a CVD event. Methods. We undertook a cross-sectional study with prospective follow-up including consecutive patients with FMF-related amyloidosis (n = 98) or other non-diabetic glomerulopathies (n = 102). All patients had nephrotic-range proteinuria and normal glomerular filtration rate. Flow-mediated dilatation (FMD) was assessedand ADMA levels, CRP and pentraxin 3 (PTX3) were determined. Patients were followed for cardiovascular events. Results. Amyloidosis patients secondary to FMF showed higher levels of ADMA, CRP and PTX3 and lower FMD as compared with patients with other glomerulopathies. Cardiovascular events (n = 54) were registered during 3 years of follow-up. Increased ADMA levels and lower FMD were observed in patients with cardiovascular risk in both groups, but especially in individuals with amyloidosis.Conclusion. Patients with FMF-related amyloidosis have increased CVD event risk, probably related to the high ADMA levels, elevated inflammatory markers and decreased FMD measures observed in these patients

The genetic structure of the Turkish population reveals high levels of variation and admixture

The construction of population-based variomes has contributed substantially to our understanding of the genetic basis of human inherited disease. Here, we investigated the genetic structure of Turkey from 3,362 unrelated subjects whose whole exomes (n = 2,589) or whole genomes (n = 773) were sequenced to generate a Turkish (TR) Variome that should serve to facilitate disease gene discovery in Turkey. Consistent with the history of present-day Turkey as a crossroads between Europe and Asia, we found extensive admixture between Balkan, Caucasus, Middle Eastern, and European populations with a closer genetic relationship of the TR population to Europeans than hitherto appreciated. We determined that 50% of TR individuals had high inbreeding coefficients (≥0.0156) with runs of homozygosity longer than 4 Mb being found exclusively in the TR population when compared to 1000 Genomes Project populations. We also found that 28% of exome and 49% of genome variants in the very rare range (allele frequency < 0.005) are unique to the modern TR population. We annotated these variants based on their functional consequences to establish a TR Variome containing alleles of potential medical relevance, a repository of homozygous loss-of-function variants and a TR reference panel for genotype imputation using high-quality haplotypes, to facilitate genome-wide association studies. In addition to providing information on the genetic structure of the modern TR population, these data provide an invaluable resource for future studies to identify variants that are associated with specific phenotypes as well as establishing the phenotypic consequences of mutations in specific genes

The genetic history of the Southern Arc: a bridge between West Asia and Europe

By sequencing 727 ancient individuals from the Southern Arc (Anatolia and its neighbors in Southeastern Europe and West Asia) over 10,000 years, we contextualize its Chalcolithic period and Bronze Age (about 5000 to 1000 BCE), when extensive gene flow entangled it with the Eurasian steppe. Two streams of migration transmitted Caucasus and Anatolian/Levantine ancestry northward, and the Yamnaya pastoralists, formed on the steppe, then spread southward into the Balkans and across the Caucasus into Armenia, where they left numerous patrilineal descendants. Anatolia was transformed by intra–West Asian gene flow, with negligible impact of the later Yamnaya migrations. This contrasts with all other regions where Indo-European languages were spoken, suggesting that the homeland of the Indo-Anatolian language family was in West Asia, with only secondary dispersals of non-Anatolian Indo-Europeans from the steppe

Symmetrical and decoupled nickel microgyroscope on insulating substrate

This paper presents a symmetrical and decoupled surface micromachined gyroscope fabricated by electroforming thick nickel on a glass substrate. The symmetric structure allows matched resonant frequencies for the drive and sense vibration modes for improved sensitivity, while the decoupled drive and sense oscillation modes prevents unstable operation due to mechanical coupling, resulting in a low zero-rate output drift. The use of a glass substrate instead of a silicon substrate reduces noise due to the parasitic signal coupling by two orders of magnitude, according to both simulation results in CoventorWare and measured results on fabricated devices. A capacitive interface circuit which is fabricated in a 0.8 mum CMOS process is hybrid connected to the gyroscope, where the circuit has an input capacitance lower than 50 fF and a sensitivity of 33 mV/fF, which are currently limited by the parasitic capacitances due to hybrid wirebonding. It has been identified that the amount of parasitic capacitances must be lower than or at least in the same order with the electrical equivalent capacitance of the gyroscope for clear mechanical resonance characteristics to be obtained. Fabricated gyroscopes have close resonant frequencies for the drive and sense modes, as 37.2 and 38.3 kHz, respectively. Calculations on measured resonance values suggest that the fabricated gyroscope with 16 mum-thick structural layer provides a Brownian noise floor of 7.3degrees/h/Hz(1/2) at vacuum. Currently, the overall rate sensitivity of the gyroscope is limited to 96degrees/h in 50 Hz bandwidth for matched-frequency operation, and it can be decreased down to 56degrees/h in 50 Hz bandwidth, by improving the quality of the electrodeposited nickel

A single-crystal silicon symmetrical and decoupled gyroscope on insulating substrate

This paper presents a single-crystal silicon symmetrical and decoupled (SYMDEC) gyroscope implemented using dissolved wafer process on an insulating substrate. The symmetric structure allows matched resonant frequencies for the drive and sense vibration modes for high rate sensitivity and low temperature-dependent drift, while the decoupled drive and sense modes prevents unstable operation due to mechanical coupling, achieving a low bias drift. The 12-15mum-thick single-crystal silicon structural layer with an aspect ratio about 10 using DRIE patterning provides a high sense capacitance of 130fF, while the insulating substrate provides a low parasitic capacitance of only 20fF. Drive and sense mode resonance frequencies of the gyroscope are measured to be 39,010Hz and 38,570Hz, respectively. Measurement results reveal that the gyroscope provides a rate sensitivity of 0.01 deg/sec in 50Hz bandwidth at vacuum

A symmetric surface micromachined gyroscope with decoupled oscillation modes

This paper reports a new symmetric gyroscope structure that allows not only matched resonant frequencies for the drive and sense vibration modes for better resolution, but also decoupled drive and sense oscillation modes for preventing unstable operation due to mechanical coupling. The symmetry and decoupling features are achieved at the same time with a new suspension beam design. The gyroscope structure is designed using a standard three-layer polysilicon surface micromachining process (MUMPs) and simulated using the MEMCAD software. Measured results show that the drive and sense mode resonant frequencies are 28,535Hz and 30,306Hz, respectively, which are in agreement with the finite element simulations. The small mismatch can be reduced further by applying different DC bias voltages to the drive and sense electrodes, improving the performance. The performance of the fabricated sensor is limited due to large parasitic capacitance between the proof mass and the substrate, nevertheless, measurements and calculations show that the sensor can sense angular rates as small as 0.37 deg/sec even in atmospheric pressure. A capacitive readout circuit for the sensor was also developed in a 0.8mm CMOS process, and the fabricated circuit detects capacitance changes smaller than 0.1fF with a sensitivity of 45mV/fF