4EBP2-regulated protein translation has a critical role in high-fat diet-induced insulin resistance in hepatocytes.

A high-fat diet (HFD) plays a critical role in hepatocyte insulin resistance. Numerous models and factors have been proposed to elucidate the mechanism of palmitic acid (PA)-induced insulin resistance. However, proteomic studies of insulin resistance by HFD stimulation are usually performed under insulin conditions, leading to an unclear understanding of how a HFD alone affects hepatocytes. Here, we mapped the phosphorylation rewiring events in PA-stimulated HepG2 cells and found PA decreased the phosphorylation level of the eukaryotic translation initiation factor 4E-binding protein 2 (4EBP2) at S65/T70. Further experiments identified 4EBP2 as a key node of insulin resistance in either HFD mice or PA-treated cells. Reduced 4EBP2 levels increased glucose uptake and insulin sensitivity, whereas the 4EBP2_S65A/T70A mutation exacerbated PA-induced insulin resistance. Additionally, the nascent proteome revealed many glycolysis-related proteins translationally regulated by 4EBP2 such as hexokinase-2, pyruvate kinase PKM, TBC1 domain family member 4, and glucose-6-phosphate 1-dehydrogenase. In summary, we report the critical role of 4EBP2 in regulating HFD-stimulated insulin resistance in hepatocytes.

Periconceptional polycyclic aromatic hydrocarbon levels in maternal hair and fetal risk for congenital heart defects.

BACKGROUND: Congenital heart defects (CHDs) have a complex etiology, and environmental factors play an important role in their occurrence. Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous chemicals, and some have teratogenic potential. However, few studies have examined PAHs exposure and CHD risk. We investigated the association between PAHs in maternal scalp hair and CHD risk. METHODS: A case-control study involving 170 severe CHD cases and 170 healthy controls was conducted, and the concentrations of 11 PAHs in maternal hair grown during the periconceptional period were quantified. A generalized linear mixed model (GLMM) was used to determine the effects of each PAHs on the risk for CHDs. Weighted quantile sum (WQS) regression and Bayesian kernel machine regression (BKMR) were used to assess the overall effects of the 11-PAHs mixture on the risk for CHDs. RESULTS: The median concentration of chrysene (CHR) was higher in CHD cases (9.75 ng/g) than in controls (6.50 ng/g). In GLMM, higher levels of CHR were associated with a 4.88-fold greater risk for CHDs (95 % confidence interval [CI]: 2.69-8.89). In WQS regression, higher levels of PAHs mixture were associated with a 2.03-fold greater CHD risk (95 % CI: 1.75-2.31), and CHR had the highest weighting (weighted 0.9346). In BKMR, CHD risks increased steadily with the levels of the PAHs mixture. CHR showed a toxic effect when the other PAHs were fixed at their 25th, 50th, or 75th percentile. No interactions among PAHs were found. CONCLUSIONS: When examined individually, a high concentration of CHR in periconceptional maternal hair was associated with an increased risk for CHDs. When considering the 11 PAHs together, higher levels of the PAHs mixture were associated with increased odds of CHD occurrence.

Isolation, Purification, and Application of Protoplasts and Transient Expression Systems in Plants.

Protoplasts, derived from plant cells, exhibit remarkable totipotency and hold significant value across a wide spectrum of biological and biotechnological applications. These versatile applications encompass protein subcellular localization and interaction analysis, gene expression regulation, functional characterization, gene editing techniques, and single-cell sequencing. Protoplasts' usability stems from their inherent accessibility and their ability to efficiently incorporate exogenous genes. In this review, we provide a comprehensive overview, including details on isolation procedures and influencing factors, purification and viability assessment methodologies, and the utilization of the protoplast transient expression system. The aim is to provide a comprehensive overview of current applications and offer valuable insights into protoplast isolation and the establishment of transient expression systems in a diverse range of plant species, thereby serving as a valuable resource for the plant science community.

Maternal exposure to heavy metals and risk for severe congenital heart defects in offspring.

BACKGROUND: Congenital heart defects (CHDs) are the most common congenital malformations with a complex etiology, and environmental factors play an important role. Large epidemiology studies on prenatal exposure to selected heavy metals and their association with risk for CHDs are scarce and joint effects are not well understood. OBJECTIVES: To examine the association between prenatal exposure to selected heavy metals and risk for CHDs. METHODS: Inductively coupled plasma mass spectrometry (ICP-MS) was used to determine the maternal plasma concentrations of arsenic, cadmium, mercury, lead, and manganese were in 303 CHD cases and 303 healthy controls that were recruited in eight hospitals in China. Generalized linear mixed model (GLMM) and Bayesian kernel machine regression (BKMR) were fitted to evaluate the individual and joint effects of metal concentrations on CHDs. RESULTS: In GLMM, two metals were each significantly associated with an increased risk for CHDs [adjusted odds ratio (95% confidence interval): mercury, 2.88 (1.22-6.77); lead, 2.74 (1.00-7.57)]. In BKMR, CHD risk increased with mixture levels of the five metals when their concentrations were at the 40th percentile or higher, compared to when all metals were below their 35th percentile, and mercury was the major metal that contributed to the mixture effect. The interaction between mercury and lead was observed in BKMR. CONCLUSIONS: Using metal concentrations in maternal plasma obtained during the second or third trimester as exposure markers, we found that the risk of CHDs increased with the levels of the mixtures of As, Cd, Hg, Pb, and Mn, with Hg being the most important contributor to the mixture effect.

Bcl2L12 Contributes to Th2-Biased Inflammation in the Intestinal Mucosa by Regulating CD4+ T Cell Activities.

The Th2-biased inflammation and immune deregulation play a critical role in the pathogenesis of ulcerative colitis (UC). Recent studies indicate that the Bcl2-like protein 12 (Bcl2L12) is associated with immune deregulation of UC. This study aims to investigate the role of Bcl2L12 in the induction of aberrant Th2-biased inflammation. In this study, peripheral blood samples were collected from patients with inflammatory bowel disease. The Th2 cell activities were analyzed by flow cytometry, real-time quantitative RT-PCR, and Western blotting. Mice with Bcl2L12-knockout CD4+ T cells were used in the experiments. The results showed that the expression of Bcl2L12 was detected in peripheral CD4+ T cells, which was significantly higher in UC patients than in healthy subjects. A positive correlation between the expression of Bcl2L12 and Th2 cytokines was detected in CD4+ T cells from UC patients. Naive CD4+ T cells with Bcl2L12 overexpression were prone to differentiate into Th2 cells. Mice with Bcl2L12 deficiency failed to induce the Th2-biased inflammation in the intestine. Bcl2L12 bound GATA3 to form a complex to enhance the binding between GATA3 and the Il4 promoter to enhance the expression of IL-4 in CD4+ T cells. CD4+ T cells with Bcl2L12 overexpression were resistant to apoptosis. In conclusion, the Bcl2L12 is a critical factor in the induction of aberrant Th2 polarization by upregulating Th2 responses and downregulating Th2 cell apoptosis. Bcl2L12 may be a novel therapeutic target in the management of the disorders with Th2-biased inflammation.

Urine volatile organic compounds as biomarkers for minimal change type nephrotic syndrome.

Urinary volatile organic compounds (VOCs) profiling has recently received considerable attention because it can be obtained noninvasively and conveniently while it can be successfully used in a variety of diseases and can provide unique biomarkers. The aim of current study was to investigate potential biomarkers between minimal change type nephrotic syndrome (MCNS) and normal. Urinary samples were collected from 38 minimal change type nephrotic syndrome patients and 15 healthy controls. Solid phase microextraction (SPME) and chromatography- mass spectrometry (GC-MS) were used to analysis the urinary metabolites. To deal with the final data, the statistical methods principal component analysis (PCA) and orthogonal partial least-squares discriminant analysis (OPLSDA) were performed. Six specific VOC biomarkers were present at abnormal levels in the urine of MCNS patients. These VOCs included trans-2,2-dimethyl-4-decene; pyrrole; carbamic acid, monoammonium salt; 1-butyne, 3,3-dimethyl-; diisopropylamine; and 4-heptanone. These biomarkers may be useful as a new diagnostic method and for monitoring the prognosis for MCNS patients.

Secondhand smoke during the periconceptional period increases the risk for orofacial clefts in offspring.

BACKGROUND: To examine whether exposure to secondhand smoke (SHS) during the periconceptional period among nonsmoking women is associated with an increased risk for orofacial clefts (OFCs) in offspring in a population with low rates of maternal active smoking but high rates of SHS exposure. METHODS: We recruited 240 women with OFC-affected pregnancies and 1420 women who delivered healthy infants from a population-based case-control study in northern China during 2002 and 2016. Data including self-reported SHS exposure were collected by trained health care workers through face-to-face interviews. Odds ratios (ORs) with 95% confidence intervals (95% CIs) were used to estimate the association between SHS exposure and OFC risk. RESULTS: The unadjusted ORs for OFCs and cleft lip with or without cleft palate (CL±P) in association with SHS exposure were both 1.6 (95% CI 1.2, 2.1). After adjusting for maternal fever or flu, farming occupation, infant sex, and history of pregnancy affected by birth defects, the adjusted ORs were both 1.6 (95% CI 1.2, 2.2). Frequent SHS exposure (>6 times/week) was associated with an even higher risk for OFCs (adjusted OR 2.6, 95% CI 1.8, 3.8) and for CL±P (adjusted OR 2.5, 95% CI 1.7, 3.7). CONCLUSIONS: Maternal SHS exposure during the periconceptional period increases the risk for OFCs in offspring among nonsmoking mothers.

The draft genome, transcriptome, and microbiome of Dermatophagoides farinae reveal a broad spectrum of dust mite allergens.

BACKGROUND: A sequenced house dust mite (HDM) genome would advance our understanding of HDM allergens, a common cause of human allergies. OBJECTIVE: We sought to produce an annotated Dermatophagoides farinae draft genome and develop a combined genomic-transcriptomic-proteomic approach for elucidation of HDM allergens. METHODS: A D farinae draft genome and transcriptome were assembled with high-throughput sequencing, accommodating microbiome sequences. The allergen gene structures were validated by means of Sanger sequencing. The mite's microbiome composition was determined, and the predominant genus was validated immunohistochemically. The allergenicity of a ubiquinol-cytochrome c reductase binding protein homologue was evaluated with immunoblotting, immunosorbent assays, and skin prick tests. RESULTS: The full gene structures of 20 canonical allergens and 7 noncanonical allergen homologues were produced. A novel major allergen, ubiquinol-cytochrome c reductase binding protein-like protein, was found and designated Der f 24. All 40 sera samples from patients with mite allergy had IgE antibodies against rDer f 24. Of 10 patients tested, 5 had positive skin reactions. The predominant bacterial genus among 100 identified species was Enterobacter (63.4%). An intron was found in the 13.8-kDa D farinae bacteriolytic enzyme gene, indicating that it is of HDM origin. The Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed a phototransduction pathway in D farinae, as well as thiamine and amino acid synthesis pathways, which is suggestive of an endosymbiotic relationship between D farinae and its microbiome. CONCLUSION: An HDM genome draft produced from genomic, transcriptomic, and proteomic experiments revealed allergen genes and a diverse endosymbiotic microbiome, providing a tool for further identification and characterization of HDM allergens and development of diagnostics and immunotherapeutic vaccines.

Unveiling the toxic effects, physiological responses and molecular mechanisms of tobacco (Nicotiana tabacum) in exposure to organic ultraviolet filters.

Exposure to organic ultraviolet (UV) filters has raised concerns due to their potential adverse effects on environments. However, their toxic mechanisms on plants remain elusive. In this study, using integrative physiological and transcriptomic approaches we investigated the physiological and molecular responses to three representative UV filters, namely oxybenzone (OBZ), avobenzone (AVB), and octinoxate (OMC), in an agricultural model plant tobacco. The exposure to UV filters disrupts the functionality of photosystem reaction centers and the light-harvesting apparatus. Concurrently, UV filters exert a suppressive effect on the expression of genes encoding Rubisco and Calvin-Benson cycle enzymes, resulting in a decreased efficiency of the Calvin-Benson cycle and consequently hampering the process of photosynthesis. Exposure to UV filters leads to significant generation of reactive oxygen species within tobacco leaves and downregulation of oxidoreductase activities. Moreover, UV filters promote abscisic acid (ABA) accumulation by inducing the expression of ABA biosynthesis genes whereas repress indole-3-acetic acid (IAA) biosynthesis gene expression, which induce leaf yellowing and slow plant growth. In summary, the organic UV filters exert toxic effects on tobacco growth by inhibiting chlorophyll synthesis, photosynthesis, and the Calvin-Benson cycle, while generating excessive reactive oxygen species. This study sheds light on the toxic and tolerance mechanisms of UV filters in agricultural crops.

Distinct toxic effects, gene expression profiles, and phytohormone responses of Polygonatum cyrtonema exposed to two different antibiotics.

The excessive usage of veterinary antibiotics has raised significant concerns regarding their environmental hazard and agricultural impact when entering surface water and soil. Animal waste serves as a primary source of organic fertilizer for intensive large-scale agricultural cultivation, including the widely utilized medicinal and edible plant, Polygonatum cyrtonem. In this study, we employed a novel plant stress tissue culture technology to investigate the toxic effects of tetracycline hydrochloride (TCH) and sulfadiazine (SDZ) on P. cyrtonema. TCH and SDZ exhibited varying degrees of influence on plant growth, photosynthesis, and the reactive oxygen species (ROS) scavenging system. Flavonoid levels increased following exposure to TCH and SDZ. The biosynthesis and signaling pathways of the growth hormones auxin and gibberellic acid were suppressed by both antibiotics, while the salicylic acid-mediated plant stress response was specifically induced in the case of SDZ. Overall, the study unveiled both common and unique responses at physiological, biochemical, and molecular levels in P. cyrtonema following exposure to two distinct types of antibiotics, providing a foundational framework for comprehensively elucidating the precise toxic effects of antibiotics and the versatile adaptive mechanisms in plants.

[The prevalence and risk factors of bronchiectasis in residents aged 40 years old and above in seven cities in China].

OBJECTIVE: To investigate the prevalence and risk factors of bronchiectasis in urban city of China. METHODS: A cross-sectional survey was conducted in 17 urban areas in Beijing, Shanghai, Tianjin, Chongqing cities, and Guangdong, Liaoning, Shanxi provinces. In this study, urban population-based cluster samples were randomly selected from each city/province. In the selected city communities, all residents at least 40 years old were recruited, interviewed with questionnaires and tested with spirometry. Each participant was asked whether he/she was ever diagnosed as bronchiectasis by physician, whether had symptoms of respiratory diseases and possible risk factors, etc. RESULT: Data of 10 811 participants was enrolled for analysis, with a response rate of 75.4% (10 811/14 337). The overall prevalence of physician-diagnosed bronchiectasis was 1.2% (135/10 811), with 1.5% (65/4382) in male and 1.1% (70/6429) in female, without statistical difference in gender (χ² = 3.289, P = 0.070). Prevalence of bronchiectasis increased with age (χ² = 31.029, P < 0.001). There were no statistical significances in crude prevalences of bronchiectasis among cities (χ² = 10.572, P = 0.103), while there was a significant difference among cities after adjustment with confounders (Wald value = 22.116, P = 0.001), by using logistic regression analysis. Logistic regression analysis showed, bronchiectasis was significantly associated with elder ( ≥ 70 years vs 40-49 years; OR = 4.11, 95% CI 2.29-7.36), the family history of respiratory diseases (having two subjects with respiratory diseases in family vs no suffered relatives; OR = 2.04, 95% CI 1.06-3.94), respiratory infection during childhood (suffering two kinds of respiratory diseases vs never; OR = 4.89, 95% CI 2.03-11.81), exposure to coal (OR = 2.30, 95% CI 1.17-4.52), chronic pharyngitis (OR = 3.96, 95% CI 1.38-11.40) and pulmonary tuberculosis (OR = 3.07, 95% CI 1.89-4.98), heart diseases (OR = 1.64, 95% CI 1.11-2.42) and lung cancer(OR = 18.61, 95% CI 7.67-45.18). CONCLUSION: The prevalence of bronchiectasis in population aged 40 years old and above in urban area in China is high and associated with multiple factors such as age, family history of respiratory diseases, respiratory infection during childhood, exposure to coal, chronic pharyngitis, pulmonary tuberculosis, heart diseases, lung cancer and so on.

[Wood smoke condensate had weak proliferation and strong necrotic effects on human airway smooth muscle cells].

OBJECTIVE: To investigate the effect of wood smoke condensate (WSC) on proliferation and necrosis of human airway smooth muscle cells (HASMCs). METHODS: Primary cultured HASMCs between passage 2 and 8 were divided into 3 groups: a control group, a WSC group and a cigarette smoke condensate (CSC) group. The viability of cells was examined by the CCK8 assays. The ratio of cellular proliferative stage (S phase) and cell cycle index were examined by fluorescent-labeled thymidine analogue uptake assays and flow cytometry. The expression of cyclin D1 was detected by quantitative reverse transcriptase polymerase chain reaction (Q-PCR) and Western blot. Cell apoptosis and necrosis were observed by the annexin-V and PI staining. Statistical analysis was performed by using the One-way ANOVA and LSD-t test. RESULTS: Cell viability reached peak at WSC 1 mg/L[(126 ± 12)%] and at CSC 10 mg/L exposure level [(142 ± 11) %] respectively. While at WSC 10 mg/L and CSC 60 mg/L exposure levels, cell viability decreased significantly to 86% and 76%, respectively, as compared with that of the blank control group[(100 ± 0)%] (q = 3.63- 9.33, P < 0.05). In the WSC 1 mg/L group, the cell proliferation ratio and the expression of cyclin D1 protein were (124 ± 20)% and 1.31 ± 0.64, respectively, the differences being significant as compared with the blank control group [(100 ± 0)%, 1.0 ± 0.0] (q = 5.85, 5.91, P < 0.05), while the expression of cyclin D1 mRNA and the percentage of S+G2M phase were 1.18 ± 0.21 and (103 ± 4)%, respectively, not significantly different as compared to the control group [(100 ± 0)%, 1.0 ± 0.0], (q = 1.16, 2.05, P > 0.05). In the CSC 10 mg/L group, the above-mentioned values were (204 ± 45)%, 1.80 ± 0.25, (140 ± 6)%, 1.48 ± 0.2, respectively, which were significantly higher than those in the blank control group (q = 5.38-16.51, P < 0.05) and in the WSC group (q = 3.33-15.35, P < 0.05). However, when HASMCs were exposed to WSC 10 mg/L, the cell death ratio was (13.39 ± 0.15)%, higher than that of the blank control group [(1.57 ± 0.41)%] and the CSC group [(6.61 ± 1.91)%] (q = 18.03, 10.34, P < 0.05). Apoptosis ratio in the CSC 40 mg/L group was [(61.8 ± 10.6)%], higher than that of the blank control group [(0.0 ± 0.0)%] and the WSC group [(1.7 ± 0.4)%] (q = 17.44, 16.95, P < 0.05). CONCLUSIONS: Exposure to WSC caused a weak proliferation of HASMCs, but resulted in cell necrosis instead of apoptosis at high doses. There was a slight difference in cell effects between the WSC group and the CSC group.

Prenatal exposure to silver is associated with an elevated risk for neural tube defects: a case-control study.

Exposure to copper, silver, and titanium has been reported to be associated with a variety of adverse effects on humans, but it is little focused on the fetus. We investigated the associations between prenatal exposure to the three metals (copper, silver, and titanium) and risk for fetal neural tube defects (NTDs). Placental samples from 408 women with pregnancies affected by NTDs and 593 women with normal pregnancies were collected from 2003 to 2016 in Pingding, Xiyang, Shouyang, Taigu, and Zezhou counties of China. Multilevel mixed-effects logistic regression and Bayesian kernel machine regression (BKMR) were used to evaluate the single and joint effects of the metals on NTDs. Silver was associated with an increased risk for NTDs in a dose-response fashion in single-metal logistic regression, with adjusted odds ratios (95% confidence intervals) of 1.78 (1.04-3.06) and 1.92 (1.11-3.32) in the second and third tertiles, respectively, compared to the lowest tertile. BKMR revealed toxic effects of silver on NTDs and the association appeared to be linear. No interaction of silver with any of the other two metals was observed. Besides, silver concentration was positively correlated with maternal certain dietary intakes. Placental high silver concentrations are associated with an elevated risk for NTDs. Maternal diet may be a source of silver exposure.

[Effects of shadow boxing training on exercise endurance and quality of life of patients with chronic obstructive pulmonary disease].

OBJECTIVE: To evaluate the effects of shadow boxing training on the exercise endurance and quality of life of Chinese patients with COPD (chronic obstructive pulmonary disease). METHODS: From May 2010 to March 2011, a total of 70 COPD patients in stable phases were recruited from Liwan, Yuexiu and Haizhu districts of Guangzhou. There were 35 patients in the shadow boxing exercise group and 35 patients in the control group. And they were matched by gender and age. The patients in the shadow boxing group exercised for 3 months while those in the control group received the conventional out-hospital management only. Their demographic, medical history, smoking status, medicinal use, spirometric data, clinical COPD questionnaire (CCQ) scores, 6-minute walking distance and Borg scores were collected before and after trial. RESULTS: A total of 63 COPD patients (33 in shadow boxing group vs. 30 in control group) completed the study. There was an average dropout rate of 5.7% (2/35) in shadow boxing group and 14.3% (5/35) in control group. No differences existed between two groups in age (67 ± 8 vs 69 ± 9 yr), male proportion (84.8% vs 86.7%), body mass index (22.8 ± 2.6 vs 22.7 ± 3.0), usage proportion of medicine (42.4% vs 33.3%), duration of disease (4.0 ± 7.5 vs 5.5 ± 7.3), percentage of smokers (78.8% vs 80.0%), 6-minute walking distance (447 ± 94 vs 414 ± 100), CCQ total score (15.0 ± 9.4 vs 14.1 ± 8.8), CCQ symptom score (9.2 ± 5.6 vs 8.3 ± 5.0) and activity score (5.8 ± 4.5 vs 5.8 ± 4.4) at baseline (all P > 0.05). At the end of study, the 6-minute walking distance of patients had statistical differences between two groups (P < 0.01). The shadow boxing group increased by (51 ± 55) m while the control dropped by (19 ± 58) m. The total score, symptom score and activity score of clinical COPD questionnaire had statistical differences between two groups. They decreased significantly in the shadow boxing group as compared with the baseline data while there was no significant change in the control group. No statistical differences existed between two groups in the changes of forced vital capacity (FVC), forced expiratory volume in one second (FEV(1)), FEV(1)% pred, Borg score and dyspnea scales. CONCLUSION: Capable of improving the exercise endurance and life quality of COPD patients, shadow boxing exercise may become one of effective rehabilitation programs for COPD patients in stable phases in communities.

[The effects of nicotine on human airway epithelial cells].

OBJECTIVE: To investigate the genome changes of primary human airway epithelial cells exposed to nicotine in vitro, and therefore to understand the effect of nicotine on the cellular physiological process and phenotypes. METHODS: The primary human airway epithelial cells were divided into 4 groups: 4 h experimental group and control group, 48 h experimental group and control group, with 1×10(8)/L cells in each culture. Total RNA was extracted from cells after incubated with nicotine (1×10(-5) mol/L) for 4 h or 48 h respectively. The genes expressed differentially were detected by a gene chip, and those related to epithelial mesenchymal transition were selected to undergo real-time PCR for verification. RESULTS: Sixty-three up-regulated genes and 44 down-regulated genes were detected in the experimental group incubated with nicotine for 4 h, which were mainly involved in the stress response. There were 860 up-regulated genes and 582 down-regulated genes found in the cells treated with 1×10(-5) mol/L nicotine for 48 h, compared with the control. These genes were mainly involved in some important physiological processes and pathways with transdifferentiation, including embryonic development, cell polarity maintaining, cell adhesion, etc. Further analysis revealed that some epithelial markers such as epithelial keratin and epithelial mucin protein were down-regulated, while mesenchymal cell markers including fiber connecting protein 1 and N-cadherin were up-regulated. The results by real-time PCR showed consistency with those by gene chip examination. CONCLUSION: Nicotine could promote a series of changes in genes related to epithelial mesenchymal transdifferentiation process in human airway epithelial cells.

[An in vitro study on the pharmacological ascorbate treatment of influenza virus].

OBJECTIVE: To investigate the effects and mechanism of pharmacological ascorbate against Influenza A/CA/7/09 (H1N12009). METHODS: NHBE cells (≈ 95% confluent monolayer) in 12-well plates (Corning) were kept at 37°C at all times. NHBE cells were exposed to A/CA/7/09 (H1N12009) influenza virus at MOI of 0.01 for 1 h, rinsed with NHBE medium, and incubated with NHBE medium containing 20 mmol/L ascorbate or 20 mmol/L ascorbate +600 IU/ml Catalase. The cells were then incubated for an additional 4 - 12 h and the culture medium was harvested for titration. Viral titers were determined as log(10) 50% tissue culture infective doses (TCID50) assay in MDCK cells. Ascorbate in NHBE medium was determined using HPLC separation coupled with coulometric electrochemical detection. Hydrogen peroxide was detected indirectly by Clark-type oxygen electrode. RESULTS: In vitro experiments showed that pharmacological ascorbate killed not only isolated viruses, but also viruses from normal human bronchial epithelial cells. The antiviral effect of ascorbic acid appeared to be dose-dependent. 2.5 mmol/L ascorbic acid was able to eliminate 90% of the viruses and 20 mmol/L ascorbic acid totally blocked viral replication in vitro. The antiviral effect of pharmacological ascorbate varied at different phases of infection. Pharmacological ascorbate eliminated viral infectivity with treatment times as short as 4 hours at early stage of infection. But the effect was reversed by catalase. CONCLUSION: Pharmacological ascorbate (vitamin C) as a pro-drug eliminates or kills influenza virus, probable by producing steady-state concentrations of hydrogen peroxide (H2O2) in extracellular fluid.

Placental concentrations of alkali metals and their associations with neural tube defects in offspring.

INTRODUCTION: The role of alkali metals in the development of neural tube defects (NTDs) is little known. We examined the associations between placental concentrations of lithium (Li), sodium (Na), potassium (K), rubidium (Rb), and cesium (Cs), and the occurrence of NTDs in fetuses. METHODS: 408 women who had NTD-affected pregnancies and 593 women who delivered healthy infants were included. Logistic regression, weight quantile sum regression (WQSR), and Bayesian kernel machine regression (BKMR) were applied to assess whether these metals are associated with the occurrence of NTDs. RESULTS: Cs showed an inverse association with the odds of NTDs [adjusted odds ratio (aOR): 0.58, 95% confidence interval (CI): 0.36-0.91] in single-metal logistic model. Estimates did not change much in the multiple-metal logistic model. In WQSR, the WQS index was inversely associated with the odds of NTDs (aOR: 0.62, 95%CI: 0.51-0.75), in which Cs (weighted 0.45) had the highest weight. In BKMR, the odds of NTDs decreased with the levels of the five-metal mixtures. Cs was associated with decreased odds of NTDs when the remaining four metals were fixed at their 25th and 50th percentiles, while Na was associated with increased odds of NTDs when setting other metals at the 25th, 50th, or 75th percentile. DISCUSSION: A high concentration of Cs and Na in placental tissue was respectively associated with decreased and increased odds of NTDs. In addition, the occurrence of NTDs decreased with the levels of the five-metal mixtures.

Prenatal uranium exposure and risk for fetal neural tube defects: A case-control study in women living in a rural area of northern China.

The adverse effects of uranium exposure on human health are well-known; less is known, however, regarding its association with congenital malformations. We conducted a case-control study to examine the association between prenatal exposure to uranium and risk for fetal neural tube defects (NTDs) using the concentration of uranium in placental tissue as an exposure marker in 408 NTD cases and 593 healthy controls. Uranium concentration was quantified with an inductively coupled plasma mass spectrometer. The odds ratios of NTDs for uranium exposure levels, categorized into quartiles, were estimated using logistic regression. The median concentration of uranium in the NTD group (0.409 ng/g) was significantly higher than that in the control group (0.218 ng/g). The risk for NTDs increased 2.52-fold (95% CI, 1.85-3.45) for concentrations of uranium above the median value for all participants. After adjusting for confounders, the risk for NTDs increased 1.36-fold (95% CI, 1.25-6.17), 1.77-fold (95% CI, 1.09-2.85), and 3.60-fold (95% CI, 2.30-5.64) for the second, third, and fourth quartiles of uranium concentrations compared to the lowest quartile, respectively. Prenatal exposure to uranium is a risk factor for NTDs in this population. Prospective studies are needed to further validate this finding.