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Classical congenital adrenal hyperplasia (CAH) is characterized by the defects in cortisol and aldosterone secretion, and accompanied with adrenal hyperandrogenism. It is likely that the impaired adrenocortical function and intermittent treatment-related hypercortisolism may predispose patients to the development of metabolic syndrome in adulthood. Our aim was to assess the impact of hyperandrogenism on metabolic profiles in CAH women without glucocorticosteroid treatment. We evaluated the clinical characteristics and metabolic profiles in 30 untreated Chinese female adults with simple virilizing congenital adrenal hyperplasia (SV-CAH). Mutation analysis was performed by sequencing the entire 21-hydroxylase gene ( CYP21A2). As compared with the controls, CAH patients had higher BMI (BMI, 21.5 ± 2.1 vs. 20.0 ± 1.8 kg/m, P < 0.05), higher 2 h post-load plasma glucose levels (6. 35 ± 1.74 vs. 5. 35 ± 1.17 mmol/l, P < 0.05), higher serum triglycerides (TG) (1.12 ± 0.64 vs. 0.63 ± 0.15 mmol/l, P < 0.01), and lower high-density lipoprotein cholesterol (HDL-c) (1.30 ± 0.39 vs. 1.67 ± 0.29 mmol/l, P < 0.01). Moreover, CAH patients had higher fasting insulin and homeostasis model assessment of insulin resistance (HOMA-IR) (1.81 ± 0.99 vs. 1.24 ± 0.50, P < 0.05), while ΔIns30/ΔGlu30 showed no statistically significant difference in two groups. In addition, a marked reduction of serum adiponectin levels were observed in CAH patients (7.0 ± 3.3 vs. 13.2 ± 4.8 μg/ml, P < 0.001), however, serum CRP levels were not different between patients and the controls. Further regression analysis showed that higher serum testosterone concentrations were associated with metabolic disorder indexes and reduction of serum adiponectin. Our study demonstrates that untreated CAH patients are prone to have metabolic disorders in association with elevated serum testosterone levels and reduced insulin insensitivity. [ABSTRACT FROM AUTHOR]

Abstract  Wolfram syndrome (WFS), also known as DIDMOAD, is an infrequent cause of diabetes mellitus. WFS is an autosomal recessive neurodegenerative disease characterized by various clinical manifestations such as diabetes mellitus, optic atrophy, diabetes insipidus, deafness, neurological symptoms, renal tract abnormalities, psychiatric disorders, and gonadal disorders. The majority of patients with WFS carry the loss of function mutations in the WFS1 gene. The exons 2–8 of the WFS1 gene from one Chinese WFS patient were amplified by the polymerase chain reaction (PCR), subcloning techniques and direct sequence determination was applied to the amplified fragments. The compound heterozygous mutation of a 3-bp (GAC) deletion (V434del) and another compound heterozygous mutation (G→N)(W666X) in exon 8 of WFS1 gene was identified in the patient. Other seventeen members of her family were investigated. Four cases with heterozygotes had been found through screening for the mutation V434del and five cases for the mutation W666X in the whole family. This is the first report of WFS with the mutation V434del and W666X in the WFS1 gene. [ABSTRACT FROM AUTHOR]

Abstract  Human essential hypertension is a complex polygenic trait with underlying genetic components that remain unknown. The spontaneously hypertensive rat (SHR) is a well-characterized experimental model for essential hypertension. By comparative proteomics, we previously identified glutathione S-transferase, mu 2 (GSTM2), a protein involved in detoxification of reactive oxygen species, which had a significant reduction in left ventricles of 16-week-old SHR compared with WKY rats. In parallel, Western blotting and RT-PCR showed a similar reduction of GSTM2 in left ventricles and aortas of 4-, 8-, and 16-week-old SHR, which is before the onset of hypertension. This suggests that differential expression is not attributable to long-term changes in blood pressure. Meanwhile, the activities of GSTM2 were significantly decreased in different ages old SHR. Conversely, there was an enhanced generation of superoxide anion and activation of NADPH oxidase in SHR, which was accompanied by an increase in the protein expression of p47phox, a subunit of NADPH oxidase. These data suggest that it maybe a reduction in antioxidant defenses, evident by a reduced expression and activity of GSTM2, in the left ventricles and aortas of SHR that leads to increased levels of superoxide anion and activation of NADPH oxidase. [ABSTRACT FROM AUTHOR]

Abstract  Hereditary fructose intolerance (HFI) is an inheritable disorder of fructose metabolism, inherited as an autosomal recessive disorder and caused by catalytic deficiency of aldolase B, which is critical for gluconeogenesis and fructose metabolism. The affected individuals develop severe hypoglycemia after taking foods containing fructose and cognate sugars. The exons 2–9 of the aldolase B (gene symbol ALDOB) gene from one Chinese HFI patient were amplified by the polymerase chain reaction (PCR), and direct sequence determination was applied to the amplified fragments. The mutation of a 4-bp (AACA) deletion (479_482 del) in exon 4 of ALDOB gene was identified in the patient, which had been reported to cause a frameshift at codon 118 and a truncated protein of 132 amino acids in the previous study. Then, the second case with the same homozygote deletion and eight cases with heterozygotes had been found through screening for the mutation c.479_482 del AACA in the whole family. This is the first report of HFI with the mutation c.479_482 del AACA in the ALDOB gene in a Chinese family. [ABSTRACT FROM AUTHOR]

The 1-mm-thick Al to Cu friction stir welding is successfully performed at the tool offsets toward Al side ranging from 0 to 2 mm. With increasing tool offset, the phenomenon of material sticking to tool shoulder surface is restricted and the area of Al–Cu mixing zone is reduced progressively. As the tool offset is increased from 0 to 1 mm, the weld shows a variation of intermetallic phases from CuAl2 + Cu9Al4 to CuAl2 and exhibits a lowering in hardness and tensile properties. The 2-mm-offset weld without intermetallic phases discernible exhibits the highest hardness due to the thinness of Cu lamellar and Al-rich compound layers, and the joint featured by a failure at the relatively soft region adjacent to harder Al–Cu mixing zone in a ductile pattern shows the best tensile strength equivalent to 80% of that of the base material. [ABSTRACT FROM AUTHOR]

High ferrotitanium prepared directly by the thermite method has a disadvantageously high O content (≥ 10 wt%) because of the short slag-metal separation time. In this study, CaO and CaF2 are added to the melt to improve the basicity of the slag and melt separation under heat preservation is performed to strengthen slag-metal separation. The thermodynamics of the step-by-step reduction process of TiO2 in the Ti–Al–Fe–Si–O system whose composition is close to the alloy after melt separation were calculated. Samples of alloys and slags before and after melt separation were systematically analyzed. The result indicates that the reaction that TiO is reduced by Al to Ti is the limited step in the reduction process of TiO2. The O content of the alloys slightly decreases with temperature from 1873 to 2023 K, which agrees with the changes in the law of deoxidation limit. It is mainly attributed to the movement of chemical reactions in the alloy melt at different temperatures and slag-metal interfacial reaction. The addition of Al2O3–CaO–CaF2 slag and high temperature promote the removal of Al2O3 and titanium suboxides. The minimum contents of O and Al in the alloy reach 1.84 wt% and 3.26 wt%, respectively. [ABSTRACT FROM AUTHOR]

Ferrotitanium is used as a deoxidizer and alloying agent during steelmaking process, which has a high demand for sulfur control. Sulfur was introduced from raw materials in the process of producing ferrotitanium by thermite method, where CaO was used as fluxing agent. At the same time, CaO has a great desulfurization capability. Effects of CaO addition on the distribution of sulfur in high titanium ferroalloy prepared by thermite method were studied in this work. The equilibrium diagram of Ti–Al–Fe–S system was calculated by FactSage 6.4 software package with FactPS and FTmisc database. The alloy and slag samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), inductively coupled plasma atomic emission spectrometer (ICP-AES), X-ray fluorescence (XRF) and high-frequency infrared ray carbon sulfur analyzer. The result indicates that the sulfur in the alloy firstly exists in the form of liquid FeS, thereafter TiS (s) and eventually Ti2S (s) during cooling. The sulfur is mainly distributed in the alloy, and only a small amount of sulfur remains in the slag. Moreover, it is noted that the sulfur in the alloy does not distribute homogeneously, and it exists in the form of solid solution phase, (Ti, Al, Fe)S. S content in the slag, the sulfur capacity of the slag and the sulfur distribution ratio (LS) all increase with the increment of CaO addition, while S content in alloys decreases. [ABSTRACT FROM AUTHOR]

Aiming at determining the thermal contact resistance of ball screws, a new analytical method combining the minimum excess principle with the MB fractal theory is proposed to estimate thermal contact resistance of ball screws considering microscopic fractal characteristics of contact surfaces. The minimum excess principle is employed for normal stress analysis. Moreover, the MB fractal theory is adopted for thermal contact resistance. The effectiveness of the proposed method is validated by self-designed experiment. The comparison between theoretical and experimental results demonstrates that thermal contact resistance of ball screws can be obtained by the proposed method. On this basis, effects of fractal parameters on thermal contact resistance of ball screws are discussed. Moreover, effects of the axial load on thermal contact resistance of ball screws are also analyzed. The conclusion can be drawn that the thermal contact resistance decreases along with the fractal dimension D increase and it increases along with the scale parameter G increase, and thermal contact resistance of ball screws is retained almost constant along with axial load increase before the preload of the right nut turns into zero in value. The application of the proposed method is also conducted and validated by the temperature measurement on a self-designed test bed. [ABSTRACT FROM AUTHOR]

Excessive vibration and noise radiation of the track structure can be caused by the operation of high speed trains. Though the track structure is characterized by obvious periodic properties and band gaps, the bandwidth is narrow and the elastic wave attenuation capability within the band gap is weak. In order to effectively control the vibration and noise of track structure, the local resonance mechanism is introduced to broaden the band gap and realize wave propagation control. The locally resonant units are attached periodically on the rail, forming a new locally resonant phononic crystal structure. Then the tuning of the elastic wave band gaps of track structure is discussed, and the formation mechanism of the band gap is explicated. The research results show that a new wide and adjustable locally resonant band gap is formed after the resonant units are introduced. The phenomenon of coupling and transition can be observed between the new locally resonant band gap and the original band gap of the periodic track structure with the band gap width reaching the maximum at the coupling position. The broader band gap can be applied for vibration and noise reduction in high speed railway track structure. [ABSTRACT FROM AUTHOR]

We present a novel methodology for preparing as-cast Ti-Al-V alloy directly from titanium-rich material through a thermite reduction. The new method is shown to be feasible through a thermodynamics and dynamics analysis. The as-cast Ti-Al-V alloys synthesized from titanium dioxide, rutile, and high-titanium slag were analyzed by an x-ray diffractometer, a scanning electron microscope, an inductively coupled plasma emission spectrometer, and an oxygen/nitrogen/hydrogen analyzer. The results indicate that the alloy is composed of a Ti-Al-V matrix and AlO inclusions. The Al and V contents in the matrix are close to the mass ratio of Ti-6Al-4V (Al: 5.5-6.8 wt.%, V: 3.5-4.5 wt.%). The Si and Fe in the alloys synthesized from rutile and high-titanium slag can be used as alloying elements in low-cost titanium alloys. The present method is expected to be useful for preparing Ti-Al-V alloys at a low production cost. [ABSTRACT FROM AUTHOR]

Based on the Padé approximation method, in this paper we determine the coefficients $a_{j}$ and $b_{j}$ ( $1\leq j \leq k$ ) such that where $k\geq 1$ is any given integer. Based on the obtained result, we establish new upper bounds for $( 1+1/x ) ^{x}$ . As an application, we give a generalized Carleman-type inequality. [ABSTRACT FROM AUTHOR]

Background and Aim: Liver enzymes including serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyltransferase (GGT) are well recognized as surrogate makers reflecting non-alcoholic fatty liver disease (NAFLD). However, the associations of serum ALT, AST and GGT with hepatic lipid contents are not well established. The aim of this study was to investigate the relationship between liver enzymes and intrahepatic triglyceride (IHTG) contents, and explore the feasibility in using liver enzymes to reflect accumulation of IHTG in obese subjects. Methods: A cross-sectional analysis was conducted in 475 obese adults aged 40-65 years. Anthropometric parameters and blood biochemical indexes including liver enzymes, glucose and lipid profiles were measured. The liver triglyceride contents of subjects were determined by H-MRS. Results: Serum ALT, AST and GGT were positively correlated with IHTG contents ( p < 0.01). Serum ALT, AST and GGT levels at the highest quartile of IHTG contents were significantly elevated as compared with those in the lowest quartile ( p < 0.01). Multivariate linear regression analysis demonstrated that serum ALT, but not AST or GGT was independently associated with IHTG contents. By logistic regression analysis, the odds ratio for higher IHTG contents was increased by 1.464 times/1 SD increase in serum ALT level after adjusting for multiple confounding factors [OR (95 % CI) 2.464 (1.584-3.834)]. However, these relationships could not be observed between serum AST or GGT with IHTG contents. Conclusions: Serum ALT level is independently correlated with the hepatic triglyceride contents in obese subjects and more appropriate to be used as a predictor for the degree of NAFLD rather than AST and GGT. [ABSTRACT FROM AUTHOR]

Two new lanthanide coordination polymers formulated as [Ln(BDC)(DMF)(HO)] [Ln = Tb ( 1), Gd ( 2)] [HBDC = 1,4-benzenedicarboxylic acid, DMF = N,N′-dimethylformamide] were synthesized under solvothermal conditions. The coordination polymers were characterized by IR spectroscopy, elemental analysis and X-ray single-crystal diffraction. The two coordination polymers are isostructural and exhibit twofold interpenetrating pcu three-dimensional open frameworks constructed by tetradentate ligand of HBDC. The fluorescence properties of 1 and 2 were investigated at 298 or 77 K both in solid state and in CHCl solvent dispersed as suspensions. Coordination polymer 1 exhibits characteristic Tb ions emission transitions of D → F ( J = 6-2) at 77 or 298 K both in the solid-state and in CHCl solvent. Moreover, the vibrational structure of 1 is more defined at 77 K, which exhibits another two D → F and D → F transitions more than that at 298 K. The lifetimes of 1 are longer at 77 K (915.2 μs in the solid state and 874.11 μs in the CHCl solvent) than that at 298 K (866.31 μs in the solid state and 801.04 μs in the CHCl solvent), which may be caused by the increase of radiative rate and decrease of non-radiative rate at low temperature. The singlet excited state (28,653 cm) and the lowest triplet energy level (23,641 cm) of HBDC ligand were calculated based on the UV-Vis absorbance edges of ligand and the phosphorescence spectrum of Gd coordination polymer ( 2) at 77 K, showing that the effective extent of energy transfer from HBDC ligand to Tb ion. Finally, thermal behaviors of the two coordination polymers were studied by thermogravimetric analysis, which exhibit thermal stability to 250 °C. [ABSTRACT FROM AUTHOR]

We compared food choice and the initial response to deterrent treated diet between fifth instars of Helicoverpa armigera, a polyphagous generalist pest, and Bombyx mori, an oligophagous specialist beneficial. Bombyx mori was more behaviorally sensitive to salicin than to caffeine. The relative sensitivities were reversed for H. armigera, which was tolerant to the highest levels of salicin found in natural sources but sensitive to caffeine. A single gustatory receptor neuron (GRN) in the medial styloconic sensillum of B. mori was highly sensitive to salicin and caffeine. The styloconic sensilla of H. armigera did not respond consistently to either of the bitter compounds. Phagostimulants also were tested. Myo-inositol and sucrose were detected specifically by two GRNs located in B. mori lateral styloconic sensillum, whereas, in H. armigera, sucrose was sensed by a GRN in the lateral sensillum, and myo-inositol by a GRN in the medial sensillum. Myo-inositol responsiveness in both species occurred at or below 10 mM, which is far below the naturally occurring concentration of 1 mM in plants. Larval responses to specific plant secondary compounds appear to have complex determinants that may include host range, metabolic capacity, and gustatory repertoire. [ABSTRACT FROM AUTHOR]

Helicoverpa armigera (Hübner) is one of the most polyphagous and cosmopolitan pest species, the larvae of which feed on numerous important crops. The gustatory system is critical in guiding insect feeding behavior. Here, we identified a gustatory receptor from H. armigera, HaGR9, which shows high levels of identity to DmGR43a from Drosophila melanogaster and BmGR9 from Bombyx mori. Reverse transcriptase PCR (RT-PCR) revealed HaGR9 is highly expressed in larval foregut, with little or no expression in other chemosensory tissues. Membrane topology studies indicated that, like two previously studied B. mori GRs, BmGR8 and BmGR53, HaGR9 has an inverted topology relative to G protein-coupled receptors (GPCRs), an intracellular N-terminus and an extracellular C-terminus. Calcium imaging studies confirmed HaGR9 is a sugar receptor showing dose-dependent responses to D-galactose, D-maltose, and D-fructose. This highly-expressed foregut-specific gustatory receptor may contribute to the regulation of larval feeding behavior. [ABSTRACT FROM AUTHOR]

2017 aluminum alloy plates with an ultrafine grained (UFG) structure were produced by equal channel angular processing (ECAP) and then were joined by underwater friction stir welding (underwater FSW). X-ray diffractometer (XRD), transmission electron microscope (TEM), scanning electron microscope (SEM) and microhardness tester were adopted to investigate the microstructural and mechanical characteristics of the FSW joint. The results indicate that an ultrafine grained microstructure with the mean grain size of ∼0.7 μm is obtained in the weld nugget by using water cooling. However, The FSW joint exhibits softening compared with the ultrafine grained based material and the heat affected zone (HAZ) has the lowest hardness owing to the coarsening of the strengthening precipitates. [ABSTRACT FROM AUTHOR]