Triglyceride glucose-waist circumference: the optimum index to screen nonalcoholic fatty liver disease in non-obese adults.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is easily neglected in the non-obese population. TyG index (triglyceride glucose Index) and TG/HDL-c (triglyceride to high-density lipoprotein cholesterol) are new indicators to evaluate insulin resistance (IR). Fibroscan is a non-invasive way to assess hepatic steatosis [by control attenuation parameters (CAP)] and fibrosis [by liver stiffness measurement (LSM)].The purpose of this study was to explore the correlation of TyG and its combination with obesity indicators [TyG-waist circumference (WC), TyG-body mass index (BMI)] and TG/HDL-c with CAP and LSM. METHOD: One thousand seven hundred seventy-six adults (age ≥ 20 years, BMI < 30 kg/m2) in the National Health and Nutrition Examination Survey (NHANES) 2017-2018 were included. The correlations of CAP and LSM to the indexes were assessed by generalized linear models.. Receiver operating characteristic (ROC) curve was performed to evaluate the diagnostic capability of the indicators on NAFLD and liver stiffness. RESULTS: Survey-weighted percentage of NAFLD in non-obese was 38.6%. In the fully adjusted models, there were positive associations of TyG, TyG-BMI, TyG-WC and TG/HDL-c to CAP, with the ßs of 24.810, 0.704, 0.29 and 2.983 (all p < 0.05), respectively. There were positive associations of TyG, TyG-BMI, TyG-WC, and TG/HDL-c to NAFLD, with ORs of 3.387, 1.03, 1.010 and 1.281 ((all p < 0.05)).The positive association was detected for TG/HDL-c and TyG-WC and LSM with ßs of 0.057 and 0.004(p = 0.021 and p = 0.003).TyG-WC were positively associated with liver stiffness with OR of 1.006(95%CI = 1.002, 1.012). Furthermore, the TyG-WC had the strongest diagnostic capability (ROC = 0.806; 95%CI: 0.785-0.826) on NAFLD in non-obese participants, with a specificity of 0.737 and sensitivity of 0.746. CONCLUSION: In US non-obese population, the TyG, TyG-BMI, TyG-WC, and TG/HDL-c are positively correlated with CAP and NAFLD. TyG-WC has clinical importance in identifying NAFLD in the non-obese population.

Host trehalose metabolism disruption by validamycin A results in reduced fitness of parasitoid offspring.

The general cutworm, Spodoptera litura (Lepidoptera: Noctuidae) is a worldwide destructive omnivorous pest and the endoparasitoid wasp Meteorus pulchricornis (Hymenoptera: Braconidae) is the dominant endoparasitoid of S. litura larvae. Trehalase is a key enzyme in insect trehalose metabolism and plays an important role in the growth and development of insects. However, the specific function of trehalase in parasitoid and host associations has been less reported. In this study, we obtained two trehalase genes (SlTre1 and SlTre2) from our previously constructed S. litura transcriptome database; they were highly expressed in 3rd instar larvae. SlTre1 was mainly expressed in the midgut, and SlTre2 was expressed highest in the head. SlTre1 and SlTre2 were highly expressed 5 days after parasitization by M. pulchricornis. Treatment with the trehalase inhibitor validamycin A significantly inhibited the expression levels of SlTre1 and SlTre2, and the trehalase activity. Besides, the content of trehalose was increased but the content of glucose was decreased 24 h after validamycin A treatment in parasitized S. litura larvae. In addition, the immune-related genes in phenoloxidase (PO) pathway and fatty acid synthesis-related genes in lipid metabolism were upregulated in parasitized host larvae after validamycin A treatment. Importantly, the emergence rate, proportion of normal adults, and body size of parasitoid offspring was decreased in parasitized S. litura larvae after validamycin A treatment, indicating that validamycin A disrupts the trehalose metabolism of parasitized host and thus reduces the fitness of parasitoid offspring. The present study provides a novel perspective for coordinating the application of biocontrol and antibiotics in agroecosystem.

Identification and functional study of detoxification-related genes in response to tolfenpyrad stress in Glyphodes pyloalis Walker (Lepidoptera: Pyralidae).

Glyphodes pyloalis Walker (G. pyloalis) is a common destructive mulberry pest. Due to the long-term and frequent use of insecticides, it has developed tolerance to commonly used insecticides. Tolfenpyrad (TFP) is a novel pyrazole heterocyclic insecticide. In order to understand the TFP detoxification mechanism of G. pyloalis larvae, we first estimated the LC30 dose of TFP for 3rd instar G. pyloalis larvae. Next, we identified genes that were differentially expressed in 3rd instar G. pyloalis larvae treated with TFP compared to the control group by transcriptome sequencing. In total, 86,949,569 and 67,442,028 clean reads were obtained from TFP-treated and control G. pyloalis larvae, respectively. A total of 5588 differentially expressed genes (DEGs) were identified in TFP-treated and control G. pyloalis larvae, of which 3084 genes were upregulated and 2504 genes were downregulated. We analyzed the expression of 43 candidate detoxification enzyme genes associated with insecticide tolerance using qPCR. According to the spatiotemporal expression pattern of DEGs, we found that CYP6ABE1, CYP333A36 and GST-epsilon8 were highly expressed in the midgut, while CarEs14 was strongly expressed in haemolymph. Furthermore, we successfully knocked down these genes by RNA interference. After silencing CYP6ABE1 and CYP333A36, bioassay showed that the mortality rate of TFP-treated G. pyloalis larvae was significantly higher compared to the control group. This study provides a theoretical foundation for understanding the sensitivity of G. pyloalis to TFP and establish the basis for the effective and green management of this pest.

Visceral fat area and body fat percentage measured by bioelectrical impedance analysis correlate with glycometabolism.

BACKGROUND: Adiposity evaluated by body mass index (BMI) is associated with glycometabolism. The aim of the investigation was to explore the correlation of visceral fat area (VFA), body fat percentage (BFP), BMI and waist circumference (WC) with type 2 diabetes mellitus (T2DM) and pre-diabetes. METHODS: A total of 18,458 participates underwent physical examination in Nanjing Drum Tower Hospital from January 2018 to April 2022 was included in this study. Data were collected retrospectively. Regression analysis was used to evaluate the relationship of VFA, BFP, WC and BMI with diabetes status, fasting blood glucose (FBG) and glycohemoglobin (HbA1c). RESULTS: After fully adjusted for multiple covariates, VFA, BFP, WC and BMI in T2DM and pre-diabetes group exceeded compared with normal group. FBG was positively correlated with VFA, BFP, WC and BMI with ßs of 2.221,0.306,0.606 and 0.175(p < 0.001). HbA1c was also positively correlated with the four indexes with ßs of 2.645, 0.328, 0.685 and 0.255(p < 0.001). Subgroup analysis shown that FBG and HbA1c were positively correlated with VFA, BFP, BMI and WC in normal and pre-diabetes group (p < 0.001). FBG was negatively correlated with BMI in T2DM group (p = 0.023). In T2DM, there were non-linear relationships of HbA1c with VFA, BFP, WC and BMI with the inflection points for about 7%. Before the inflection point, HbA1c was positively correlated with obesity-related indicators, and it was reversed after the inflection point. In the individuals with excessive VFA and normal BMI, the risk for glycometabolism disorder exceed compared with normal VFA and normal BMI. Every per-standard deviation increasing in VFA, BFP, WC and BMI, the corresponding risk increasing of glycometabolism disorder was 16.4, 14.6, 22.6 and 22.2%. CONCLUSION: The study demonstrated that in adults with T2DM or prediabetes, the VFA, BFP, WC and BMI were higher than with normal glycometabolism. In pre-diabetes and normal population, there were positive correlations of HbA1c and FBG with obesity-related indicators. In T2DM with poor glycemic control (HbA1c > 7%), there might be a trend of fat loss. VFA could negatively affect glycometabolism independently from BMI. The optimum to evaluate the risk of glycometabolism disorder was WC.

Waist circumference prediction for epidemiological research using gradient boosted trees.

BACKGROUND: Waist circumference is becoming recognized as a useful predictor of health risks in clinical research. However, clinical datasets tend to lack this measurement and self-reported values tend to be inaccurate. Predicting waist circumference from standard physical features could be a viable method for generating this information when it is missing or mitigating the impact of inaccurate self-reports. This study determined the degree to which the XGBoost advanced machine learning algorithm could build models that predict waist circumference from height, weight, calculated Body Mass Index, age, race/ethnicity and sex, whether they perform better than current models based on linear regression, and the relative importance of each feature in this prediction. METHODS: We trained tree-based models (via XGBoost gradient boosting) and linear models (via regression) to predict waist circumference from height, weight, Body Mass Index, age, race/ethnicity and sex (n = 60,740 participants). We created 10 iterations of each model, each using 90% of the dataset for training and the remaining 10% for testing performance (this group was different for each iteration). We calculated model performance and feature importance as an average across 10 iterations. We then externally validated the ensembled version of the top model. RESULTS: The XGBoost model predicted waist circumference with a mean bias ± standard deviation of 0.0 ± 0.04 cm and a root mean squared error of 4.7 ± 0.05 cm, with performance varying slightly by sex and race/ethnicity. The XGBoost model showed varying degrees of improvement over linear regression models. The top 3 predictors were Body Mass Index, weight and race (Asian). External validation found that on average this model overestimated waist circumference by 4.65 cm in the United Kingdom population (mainly due to overprediction in females) and underestimated waist circumference by 1.7 cm in the Chinese population. The respective root mean squared errors were 7.7 cm and 7.1 cm. CONCLUSIONS: XGBoost-based models accurately predict waist circumference from standard physical features. Waist circumference prediction using this approach would be valuable for epidemiological research and beyond.

Importance of general adiposity, visceral adiposity and vital signs in predicting blood biomarkers using machine learning.

INTRODUCTION: Blood biomarkers are measured for their ability to characterise physiological and disease states. Much is known about linear relations between blood biomarker concentrations and individual vital signs or adiposity indexes (eg, BMI). Comparatively little is known about non-linear relations with these easily accessible features, particularly when they are modelled in combination and can potentially interact with one another. METHODS: In this study, we used advanced machine learning algorithms to create non-linear computational models for predicting blood biomarkers (cells, lipids, metabolic factors) from age, general adiposity (BMI), visceral adiposity (Waist-to-Height Ratio, a Body Shape Index) and vital signs (systolic blood pressure, diastolic blood pressure, pulse). We determined the predictive power of the overall feature set. We further calculated feature importance in our models to identify the features with the strongest relations with each blood biomarker. Data were collected in 2018 and 2019 and analysed in 2020. RESULTS: Our findings characterise previously unknown relations between these predictors and blood biomarkers; in many instances the importance of certain features or feature classes (general adiposity, visceral adiposity or vital signs) differed from their expected contribution based on simplistic linear modelling techniques. CONCLUSIONS: This work could lead to the formation of new hypotheses for explaining complex biological systems and informs the creation of predictive models for potential clinical applications.

Structures of Mycobacterium tuberculosis Penicillin-Binding Protein 3 in Complex with Five ß-Lactam Antibiotics Reveal Mechanism of Inactivation.

Because of ß-lactamase-mediated resistance, ß-lactam antibiotics were long considered ineffective drugs for tuberculosis (TB) treatment. However, some ß-lactams, including meropenem and faropenem, are being re-evaluated in patients infected with TB. Penicillin-binding protein (PBP) 3, or ftsI, is an essential transpeptidase in Mycobacterium tuberculosis (Mtb) required for cell division, and thus it is an important drug target. Structures of apo MtbPBP3 and of complexes with five ß-lactams, including meropenem and faropenem, reveal how they cause inactivation via formation of hydrolytically stable acyl-enzyme complexes. The structures reveal unique features of the antibiotic interactions, both in terms of differences in their binding to MtbPBP3 and in comparison with structures of other PBPs and serine ß-lactamases, including the tautomerization status of the carbapenem-derived acyl-enzyme complexes. The results suggest that rather than hoping PBP inhibitors developed for other infections will work against TB, work should focus on developing PBP inhibitors specialized for treating TB. SIGNIFICANCE STATEMENT: The structures of Mycobacterium tuberculosis penicillin-binding protein 3, an essential protein in M. tuberculosis, in complex with a number of widely used ß-lactam antibiotics (e.g., meropenem, aztreonam, and amoxicillin) were solved. These data provide new insights for next-generation rational approaches to design tuberculosis (TB)-specific ß-lactam or nonlactam antibiotics. This manuscript is a seminal article in the field of anti-TB drug discovery and suitable for the broad readership.

Microsurgical scleral drainage and trabeculectomy-scleral flap adjustable suture combination technique in the treatment of primary glaucoma.

OBJECTIVE: To investigate the clinical effect of microsurgical scleral drainage and trabeculectomy combined with scleral flap adjustable suture technique in the treatment of primary glaucoma. METHODS: One hundred primary glaucoma patients (120 eyes) in Xinyu People's Hospital of Jiangxi province were selected from July 2014 to June 2016. The patients were randomly divided into control group and study group. The control group was treated with compound trabeculectomy, while the study group was treated with microsurgical scleral drainage and trabeculectomy combined with scleral flap adjustable suture technique. In both groups of patients, intraocular pressure, functional filtering bleb formation, and complications before and after surgery were monitored for three days, one week, one month, three months, six months and one year, while anterior chamber depth was determined one week after operation. The extent of success of operation was compared between the two groups. RESULTS: At three days, one week, one month, three months, six months and one year after surgery, intraocular pressure of study group was significantly lower than that of the control group (P<0.05). There was 93.33% formation of functional filtering blebs in the study group, which was significantly higher than that in the control group (60.00%, P<0.001). Moreover, normal anterior chamber formation was significantly higher in the study group (91.67%) than in the control group (71.67%, P<0.01). There was 95.00% operation success in the study group, relative to 68.33% success in the control group (P<0.001). CONCLUSION: Microsurgical scleral drainage and trabeculectomy combined with scleral flap adjustable suture technique has better curative effect on primary glaucoma than compound trabeculectomy. Moreover, it does not exacerbate complications. Therefore, the combination treatment technique merits clinical application.

The crystal structure of the phosphotriesterase from M. tuberculosis, another member of phosphotriesterase-like lactonase family.

Organophosphates (OPs) have been used widely as insecticides for protecting the agricultural crops from the pests. These compounds are highly toxic because they can cause the irreversible damage to human nervous system. Phosphotriesterases (PTEs), widely exist in many different kinds of bacteria, insects and mammals, can hydrolyze phosphotriesters (one major kind of OP) sufficiently. The phosphotriesterase-activities of PTEs are considered to derive from the lactonase-activities during the evolution, and phosphotriesterase-like lactonase family (PLL), is the closest protein family to PTE family based on protein-protein blast results. But members of PLL family exhibit higher lactonase activities than the phosphotriesterase activities, while the best substrates for PTEs are phosphotriesters. In this paper, the X-ray crystal structure of phosphotriesterase from M. tuberculosis (mPHP) was solved at a resolution of 2.3 Å. The structure reveals that the mPHP is a dimer with a typical distorted (ß/α)8 barrel structure like other structures of PLL family and PTE family. The architecture of active pocket of mPHP coordinates with 2 metal ions which is also similar to other PLLs and PTEs. The activity assay proved the mPHP is biological active form and the Atomic Absorption Spectroscopy assay gave the evidence that the two metal ions bound to the active pocket were Zinc cations. The structural comparison between mPHP and other homologues concluded that the mPHP should belong to PLL family, not PTE family.

Structural analysis of molybdopterin synthases from two mycobacterial pathogens.

The molybdenum cofactor, composed of molybdopterin and molybdenum, is a necessary compound for the catalytic activity of molybdenum enzymes. Molybdenum cofactor biosynthesis is a conserved multi-step process involving several enzymes. Molybdopterin synthase, a hetero-tetrameric enzyme composed of a pair of MoaE-MoaD subunits, catalyzes the generation of the cis-dithiolene group of molybdopterin in the second step of the process. The cis-dithiolene group can covalently bind molybdenum. Most mycobacterial species possess several genes encoding the full pathway of molybdenum cofactor biosynthesis. In M. smegmatis, the moaD2 and moaE2 genes encode the functional molybdopterin synthase. However, M. tuberculosis has genes encoding several molybdopterin synthase subunit homologs, including moaD1, moaD2, moaE1, moaE2, and moaX, which encodes a MoaD-MoaE fusion protein. Previous studies have shown that moaD2 and moaE2 encode functional molybdopterin synthase. Here, we report the crystal structures of two substrate-free molybdopterin synthases from two different mycobacterial pathogens, M. tuberculosis and M. smegmatis, at 2.1 Šand 2.6 Šresolutions, respectively. The overall structure of both molybdopterin synthases was hetero-tetrameric, consisting of a MoaE2 dimer flanked on either side by single MoaD2 subunits. The carboxyl-terminal domain of MoaD2 inserted into MoaE2, forming the active pocket. A comparison with previously reported molybdopterin synthase structures showed that substrate-binding and catalytic residues were conserved, despite low sequence similarity among these enzymes. The low sequence identity at the MoaE-MoaD heterodimer interface may provide the structural basis to explore mycobacterial inhibitors.

Crystal structure and biochemical study on argininosuccinate lyase from Mycobacterium tuberculosis.

Argininosuccinate lyase (ASL) participates in arginine synthesis through catalysing a reversible reaction in which argininosuccinate (AS) converts into arginine and fumarate. ASL from Mycobacterium tuberculosis is essential for its growth. In this work, the crystal structure of the apo form of MtbASL was determined and reveals a tetrameric structure that is essential for its activity since the active sites are formed by residues from three different monomers. Subsequently, we determined the crystal structure of MtbASL-sulfate complex, and the ligand mimics the negatively charged intermediate. The complex structure and mutagenesis studies indicate that residues S282 and H161 might act as a catalytic dyad. A major conformational change in the MtbASL-SO4 complex structure could be observed upon sulfate binding, and this movement facilitates the interaction between substrate and the residues involved in catalysis. A different conformational change in the C-terminal domain could be observed in the MtbASL-SO4 complex compared with that in other homologues. This difference may be responsible for the lower activity of MtbASL, which is related to the slow growth rate of M. tuberculosis. The C-terminal domain is a potential allosteric site upon inhibitor binding. The various conformational changes and the diversity of the sequence of the potential allosteric site across the homologues might provide clues for designing selective inhibitors against M. tuberculosis.

Infection Is Not Required for Mucoinflammatory Lung Disease in CFTR-Knockout Ferrets.

RATIONALE: Classical interpretation of cystic fibrosis (CF) lung disease pathogenesis suggests that infection initiates disease progression, leading to an exuberant inflammatory response, excessive mucus, and ultimately bronchiectasis. Although symptomatic antibiotic treatment controls lung infections early in disease, lifelong bacterial residence typically ensues. Processes that control the establishment of persistent bacteria in the CF lung, and the contribution of noninfectious components to disease pathogenesis, are poorly understood. OBJECTIVES: To evaluate whether continuous antibiotic therapy protects the CF lung from disease using a ferret model that rapidly acquires lethal bacterial lung infections in the absence of antibiotics. METHODS: CFTR (cystic fibrosis transmembrane conductance regulator)-knockout ferrets were treated with three antibiotics from birth to several years of age and lung disease was followed by quantitative computed tomography, BAL, and histopathology. Lung disease was compared with CFTR-knockout ferrets treated symptomatically with antibiotics. MEASUREMENTS AND MAIN RESULTS: Bronchiectasis was quantified from computed tomography images. BAL was evaluated for cellular differential and features of inflammatory cellular activation, bacteria, fungi, and quantitative proteomics. Semiquantitative histopathology was compared across experimental groups. We demonstrate that lifelong antibiotics can protect the CF ferret lung from infections for several years. Surprisingly, CF animals still developed hallmarks of structural bronchiectasis, neutrophil-mediated inflammation, and mucus accumulation, despite the lack of infection. Quantitative proteomics of BAL from CF and non-CF pairs demonstrated a mucoinflammatory signature in the CF lung dominated by Muc5B and neutrophil chemoattractants and products. CONCLUSIONS: These findings implicate mucoinflammatory processes in the CF lung as pathogenic in the absence of clinically apparent bacterial and fungal infections.

A Structural Model of a P450-Ferredoxin Complex from Orientation-Selective Double Electron-Electron Resonance Spectroscopy.

Cytochrome P450 (CYP) monooxygenases catalyze the oxidation of chemically inert carbon-hydrogen bonds in diverse endogenous and exogenous organic compounds by atmospheric oxygen. This C-H bond oxy-functionalization activity has huge potential in biotechnological applications. Class I CYPs receive the two electrons required for oxygen activation from NAD(P)H via a ferredoxin reductase and ferredoxin. The interaction of Class I CYPs with their cognate ferredoxin is specific. In order to reconstitute the activity of diverse CYPs, structural characterization of CYP-ferredoxin complexes is necessary, but little structural information is available. Here we report a structural model of such a complex (CYP199A2-HaPux) in frozen solution derived from distance and orientation restraints gathered by the EPR technique of orientation-selective double electron-electron resonance (os-DEER). The long-lived oscillations in the os-DEER spectra were well modeled by a single orientation of the CYP199A2-HaPux complex. The structure is different from the two known Class I CYP-Fdx structures: CYP11A1-Adx and CYP101A1-Pdx. At the protein interface, HaPux residues in the [Fe2S2] cluster-binding loop and the α3 helix and the C-terminus residue interact with CYP199A2 residues in the proximal loop and the C helix. These residue contacts are consistent with biochemical data on CYP199A2-ferredoxin binding and electron transfer. Electron-tunneling calculations indicate an efficient electron-transfer pathway from the [Fe2S2] cluster to the heme. This new structural model of a CYP-Fdx complex provides the basis for tailoring CYP enzymes for which the cognate ferredoxin is not known, to accept electrons from HaPux and display monooxygenase activity.

Structural characterization of the HCoV-229E fusion core.

HCoV-229E spike (S) protein mediates virion attachment to cells and subsequent fusion of the viral and cellular membranes. This protein is composed of an N-terminal receptor-binding domain (S1) and a C-terminal trans-membrane fusion domain (S2). S2 contains a highly conserved heptad repeat 1 and 2 (HR1 and HR2). In this study, the HRs sequences were designed and connected with a flexible linker. The recombinant fusion core protein was crystallized and its structure was solved at a resolution of 2.45 Å. Then we characterized the binding of HR1s and HR2s via both sequence alignment and structural analysis. The overall structures, especially the residues in some positions of HR2 are highly conserved. Fourteen hydrophobic and three polar residues from each HR1 peptide are packed in layers at the coiled-coil interface. These core amino acids can be grouped into seven heptad repeats. Analysis of hydrophobic and hydrophilic interactions between HR2 helix and HR1 helices, shows that the HR1 and HR2 polypeptides are highly complementary in both shape and chemical properties. Furthermore, the available knowledge concerning HCoV-229E fusion core may make it possible to design small molecule or polypeptide drugs targeting membrane fusion, a crucial step of HCoV-229E infection.

Crystal structure of the apurinic/apyrimidinic endonuclease IV from Mycobacterium tuberculosis.

Endonuclease IV is a typical endonuclease of the apurinic-apyrimidinic (AP) or abasic endonuclease superfamily. It repairs damaged DNA through base excision repair by cleaving the DNA backbone immediately 5' of an AP site. In Mycobacterium tuberculosis, endonuclease IV is the major AP endonuclease. This enzyme is absent from mammalian cells, making it an attractive target for anti-tuberculosis drug development. In this study, the structure of the recombinant endonuclease IV from M. tuberculosis (MtbEndo IV) was determined at a high resolution of 1.18 Å. MtbEndo IV was found to have a classical α8ß8-fold TIM barrel with loops on its surface connecting the α-helices and ß-strands that constitute a groove for DNA binding. Three zinc ions were identified at the active site. A comparison between the structures of MtbEndo IV and Escherichia coli End IV suggested that Gln32 of MtbEndo IV may plays a role in regulating substrate binding.

Age-related change in thyroid-stimulating hormone: a cross-sectional study in healthy euthyroid population.

This cross-sectional study aimed to examine changes in thyroid-stimulating hormone (TSH) concentration over age in China and investigate relationship between TSH and risk factors for cardiovascular disease (CVD) among euthyroid subjects. TSH, free triiodothyronine (FT3), free thyroxine (FT4), blood lipid, and glucose were measured. 7,693 individuals were subdivided into different age groups. Associations between TSH and CVD risk factors [age, body mass index (BMI), systolic and diastolic blood pressure, total cholesterol (TC), triglycerides, low density lipoprotein-cholesterol (LDL-C) and high density lipoprotein-cholesterol (HDL-C) and fasting plasma glucose (FPG)] were evaluated with Pearson correlation analysis. Results showed that 2.5th percentile for TSH was consistent across age groups, whereas 97.5th percentile increased in subjects older than 40 years with upper limit being 6.83 mIU/L in subjects aged 60-69 years and 8.07 mIU/L in those older than 70 years. The age-specific upper limits reclassification rate was higher in all age bands as compared to the common cut-off value. TSH was positively associated with age, SBP, DBP, TC and LDL-C and negatively with FT3 and FT4. Serum TSH within new reference range had a linear correlation with SBP, TC and LDL-C in subjects aged <60 years. There were no significant differences in BMI, blood pressure, lipid profile or FPG among subjects 60-69 and older than or equal to 70 years. Elevated TSH within new reference range is associated with risk factors for CVD in subjects aged <60 years. Thus, there might be age-related difference in the relationship between CVD risk factors and elevated serum TSH.

Ultrasound-assisted temperature-controlled ionic liquid emulsification microextraction coupled with capillary electrophoresis for the determination of parabens in personal care products.

We developed a CE and ultrasound-assisted temperature-controlled ionic liquid emulsification microextraction method for the determination of four parabens (methyl paraben, ethyl paraben, propyl paraben, and butyl paraben) in personal care products including mouthwash and toning lotion. In the proposed extraction procedure, ionic liquid (IL, 1-octyl-3-methylimidazolium hexafluorophosphate) was used as extraction solvent, moreover, no disperser solvent was needed. Parameters affecting the extraction efficiency including volume of IL, heating temperature, ultrasonic time, extraction time, sample pH, ionic strength, and centrifugation time were optimized. Under the optimized conditions, the method was found to be linear over the range of 3-500 ng/mL with coefficient of determination (R(2) ) in the range of 0.9990-0.9998. The LODs and LOQs for the four parabens were 0.45-0.72 ng/mL and 1.50-2.40 ng/mL, respectively. Intraday and interday precisions (RSDs, n = 5) were in the range of 5.4-6.8% and 7.0-8.7%, respectively. The recoveries of parabens at different spiked levels ranged from 71.9 to 119.2% with RSDs less than 9.5%.

Preparation of porous aromatic framework/ionic liquid hybrid composite coated solid-phase microextraction fibers and their application in the determination of organochlorine pesticides combined with GC-ECD detection.

A novel hybrid material incorporating porous aromatic frameworks and an ionic liquid, 1-(triethoxy silyl)propyl-3-aminopropyl imidazole hexafluorophosphate, was prepared as solid-phase microextraction coating and employed for the extraction of organochlorine pesticides. Combining the advantages of porous aromatic frameworks and an ionic liquid, the fiber exhibited a high adsorption capacity for organochlorine pesticides. Under optimized experimental conditions, enhancement factors of 247-1696 were obtained with good linearity in the range of 1-500 µg L(-1). The detection limits and quantification limits were determined to be in the range of 0.11-0.29 µg L(-1) and 0.35-0.93 µg L(-1). The relative standard deviations for six replicates of organochlorine pesticides were in the range of 4.4%-7.2% and 5.7%-10.1% for one fiber and fiber-to-fiber, respectively. By coupling with a gas chromatography-electron capture detector, the novel fiber was successfully used for the determination of organochlorine pesticides in juice and milk samples with recoveries of 76.1%-121.3%.

Defective innate immunity and hyperinflammation in newborn cystic fibrosis transmembrane conductance regulator-knockout ferret lungs.

Mucociliary clearance (MCC) and submucosal glands are major components of airway innate immunity that have impaired function in cystic fibrosis (CF). Although both of these defense systems develop postnatally in the ferret, the lungs of newborn ferrets remain sterile in the presence of a functioning cystic fibrosis transmembrane conductance regulator gene. We evaluated several components of airway innate immunity and inflammation in the early CF ferret lung. At birth, the rates of MCC did not differ between CF and non-CF animals, but the height of the airway surface liquid was significantly reduced in CF newborn ferrets. CF ferrets had impaired MCC after 7 days of age, despite normal rates of ciliogenesis. Only non-CF ferrets eradicated Pseudomonas directly introduced into the lung after birth, whereas both genotypes could eradicate Staphylococcus. CF bronchoalveolar lavage fluid (BALF) had significantly lower antimicrobial activity selectively against Pseudomonas than non-CF BALF, which was insensitive to changes in pH and bicarbonate. Liquid chromatography-tandem mass spectrometry and cytokine analysis of BALF from sterile Caesarean-sectioned and nonsterile naturally born animals demonstrated CF-associated disturbances in IL-8, TNF-α, and IL-ß, and pathways that control immunity and inflammation, including the complement system, macrophage functions, mammalian target of rapamycin signaling, and eukaryotic initiation factor 2 signaling. Interestingly, during the birth transition, IL-8 was selectively induced in CF BALF, despite no genotypic difference in bacterial load shortly after birth. These results suggest that newborn CF ferrets have defects in both innate immunity and inflammatory signaling that may be important in the early onset and progression of lung disease in these animals.

Mechanism of dephosphorylation of glucosyl-3-phosphoglycerate by a histidine phosphatase.

Mycobacterium tuberculosis (Mtb) synthesizes polymethylated polysaccharides that form complexes with long chain fatty acids. These complexes, referred to as methylglucose lipopolysaccharides (MGLPs), regulate fatty acid biosynthesis in vivo, including biosynthesis of mycolic acids that are essential for building the cell wall. Glucosyl-3-phosphoglycerate phosphatase (GpgP, EC 5.4.2.1), encoded by Rv2419c gene, catalyzes the second step of the pathway for the biosynthesis of MGLPs. The molecular basis for this dephosphorylation is currently not understood. Here, we describe the crystal structures of apo-, vanadate-bound, and phosphate-bound MtbGpgP, depicting unliganded, reaction intermediate mimic, and product-bound views of MtbGpgP, respectively. The enzyme consists of a single domain made up of a central ß-sheet flanked by α-helices on either side. The active site is located in a positively charged cleft situated above the central ß-sheet. Unambiguous electron density for vanadate covalently bound to His(11), mimicking the phosphohistidine intermediate, was observed. The role of residues interacting with the ligands in catalysis was probed by site-directed mutagenesis. Arg(10), His(11), Asn(17), Gln(23), Arg(60), Glu(84), His(159), and Leu(209) are important for enzymatic activity. Comparison of the structures of MtbGpgP revealed conformational changes in a key loop region connecting ß1 with α1. This loop regulates access to the active site. MtbGpgP functions as dimer. L209E mutation resulted in monomeric GpgP, rendering the enzyme incapable of dephosphorylation. The structures of GpgP reported here are the first crystal structures for histidine-phosphatase-type GpgPs. These structures shed light on a key step in biosynthesis of MGLPs that could be targeted for development of anti-tuberculosis therapeutics.