Vitamin D3 exacerbates steatosis while calcipotriol inhibits inflammation in non-alcoholic fatty liver disease in Sod1 knockout mice: a comparative study of two forms of vitamin D

The role of vitamin D (VD) in non-alcoholic fatty liver disease (NAFLD) remains controversial, possibly due to the differential effects of various forms of VD. In our study, Sod1 gene knockout (SKO) mice were utilized as lean NAFLD models, which were administered 15 000 IU VD3 per kg diet, or intraperitoneally injected with the active VD analog calcipotriol for 12 weeks. We found that VD3 exacerbated hepatic steatosis in SKO mice, with an increase in the levels of Cd36, Fatp2, Dgat2, and CEBPA. However, calcipotriol exerted no significant effect on hepatic steatosis. Calcipotriol inhibited the expression of Il-1a, Il-1b, Il-6, Adgre1, and TNF, with a reduction of NFκB phosphorylation in SKO mice. No effect was observed by either VD3 or calcipotriol on hepatocyte injury and hepatic fibrosis. Co-immunofluorescence stains of CD68, a liver macrophage marker, and VDR showed that calcipotriol reduced CD68 positive cells, and increased the colocalization of VDR with CD68. However, VD3 elevated hepatocyte VDR expression, with no substantial effect on the colocalization of VDR with CD68. Finally, we found that VD3 increased the levels of serum 25(OH)D3 and 24,25(OH)2D3, whereas calcipotriol decreased both. Both VD3 and calcipotriol did not disturb serum calcium and phosphate levels. In summary, our study found that VD3 accentuated hepatic steatosis, while calcipotriol diminished inflammation levels in SKO mice, and the difference might stem from their distinct cellular selectivity in activating VDR. This study provides a reference for the application of VD in the treatment of lean NAFLD.

[Analysis of the efficacy of transnasal endoscopic annulus of zinn area decompression in the treatment of dysthyroid optic neuropathy]

Objective: To evaluate the early efficacy and safety of transnasal endoscopic decompression in the annulus of zinn (AZ) region for refractory dysthyroid optic neuropathy (DON) and to preliminarily analyze the correlated factors of postoperative visual function outcome. Methods: From July 2021 to January 2023, 35 patients (56 eyes) with DON who received AZ area decompression in Peking University Third Hospital were included retrospectively, including 9 males (13 eyes) and 26 females (43 eyes), aging (52.2±12.0) years. Among them, 35 eyes underwent two-wall (medial and inferior) orbital decompression using an endonasal endoscopic approach, while 21 eyes received three-wall (medial, lateral, and inferior) orbital decompression through a combined approach. Key parameters such as best corrected visual acuity (BCVA), visual field (MD value), eyeball prominence, intraocular pressure, and complications were recorded. Postoperative data were collected one month after surgery. The statistical analysis was performed using paired t-test and Spearman correlation analysis. Results: Significant outcomes were observed post surgery in BCVA, visual field, intraocular pressure and proptosis (t value was 8.37, 6.17, 4.50, and 9.20, respectively, all P<0.001). The reduction in proptosis was statistically significant between the 2-wall and 3-wall orbital decompression groups (t=-2.82, P=0.007). Changes in BCVA, visual field, and intraocular pressure before and after surgery was greater in the 3-wall orbital decompression group compared to 2-wall orbital decompression group, although the difference was not statistically significant (all P>0.05). Change in postoperative visual acuity and visual field was significantly positively correlated with preoperative visual acuity and preoperative visual field (all P<0.001). Similarly, change in intraocular pressure and proptosis was positively correlated with preoperative intraocular pressure and preoperative protrusion (all P<0.001). Preoperative diplopia was reported in seven patients (20.0%), and two new cases (5.7%) were noted post-operation, which resolved within 3 months after surgery. Conclusions: Endoscopic endonasal decompression of the AZ area is a safe and effective surgical treatment for DON, with notable improvements in BCVA. Furthermore, three-orbital wall decompression seems to yield better outcomes in terms of eye retraction.

Dissecting the role of cadmium, lead, arsenic, and mercury in non-alcoholic fatty liver disease and non-alcoholic steatohepatitis

The objective of the present study was to review the existing epidemiological and laboratory findings supporting the role of toxic metal exposure in non-alcoholic fatty liver disease (NAFLD). The existing epidemiological studies demonstrate that cadmium (Cd), lead (Pb), arsenic (As), and mercury (Hg) exposure was associated both with an increased risk of NAFLD and altered biochemical markers of liver injury. Laboratory studies demonstrated that metal exposure induces hepatic lipid accumulation resulting from activation of lipogenesis and inhibition of fatty acid β-oxidation due to up-regulation of sterol regulatory element-binding protein 1 (SREBP-1), carbohydrate response element binding protein (ChREBP), peroxisome proliferator-activated receptor γ (PPARγ), and down-regulation of PPARα. Other metabolic pathways involved in this effect may include activation of reactive oxygen species (ROS)/extracellular signal-regulated kinase (ERK) and inhibition of AMP-activated protein kinase (AMPK) signaling. The mechanisms of hepatocyte damage during development of metal-induced hepatic steatosis were shown to involve oxidative stress, endoplasmic reticulum stress, pyroptosis, ferroptosis, and dysregulation of autophagy. Induction of inflammatory response contributing to progression of NAFLD to non-alcoholic steatohepatitis (NASH) upon toxic metal exposure was shown to be mediated by up-regulation of nuclear factor κB (NF-κB) and activation of NRLP3 inflammasome. Moreover, epigenetic effects of the metals, as well as their effect on gut microbiota and gut wall integrity were also shown to mediate their role in NAFLD development. Despite being demonstrated for Cd, Pb, and As, the contribution of these mechanisms into Hg-induced NAFLD is yet to be estimated. Therefore, further studies are required to clarify the intimate mechanisms underlying the relationship between heavy metal and metalloid exposure and NAFLD/NASH to reveal the potential targets for treatment and prevention of metal-induced NAFLD.

Biology and Roles in Diseases of Selenoprotein I Characterized by Ethanolamine Phosphotransferase Activity and Antioxidant Potential

Selenoprotein I (SELENOI) has been demonstrated to be an ethanolamine phosphotransferase (EPT) characterized by a nonselenoenzymatic domain and to be involved in the main synthetic branch of phosphatidylethanolamine (PE) in the endoplasmic reticulum. Therefore, defects of SELENOI may affect the health status through the multiple functions of PE. On the other hand, selenium (Se) is covalently incorporated into SELENOI as selenocysteine (Sec) in its peptide, which forms a Sec-centered domain as in the other members of the selenoprotein family. Unlike other selenoproteins, Sec-containing SELENOI was formed at a later stage of animal evolution, and the high conservation of the structural domain for PE synthesis across a wide range of species suggests the importance of EPT activity in supporting the survival and evolution of organisms. A variety of factors, such as species characteristics (age and sex), diet and nutrition (dietary Se and fat intakes), SELENOI-specific properties (tissue distribution and rank in the selenoproteome), etc., synergistically regulate the expression of SELENOI in a tentatively unclear interaction. The N- and C-terminal domains confer 2 distinct biochemical functions to SELENOI, namely PE regulation and antioxidant potential, which may allow it to be involved in numerous physiological processes, including neurological diseases (especially hereditary spastic paraplegia), T cell activation, tumorigenesis, and adipocyte differentiation. In this review, we summarize advances in the biology and roles of SELENOI, shedding light on the precise regulation of SELENOI expression and PE homeostasis by dietary Se intake and pharmaceutical or transgenic approaches to modulate the corresponding pathological status.

[A case of orbital rhabdomyosarcoma combined with neurofibromatosis type 1 in a child]

This article presents a case of orbital rhabdomyosarcoma (RMS) in a child who also had neurofibromatosis type 1 (NF-1). Although NF-1 is a common neurogenetic disease, there are few reports of its combination with orbital RMS. The patient underwent surgical removal of the tumor at the age of one, but the cancer recurred after five years. Following pathological and genetic diagnosis, the patient was confirmed to have orbital RMS combined with NF-1. After surgical treatment and chemotherapy, the patient's eye condition has stabilized. This article focuses on analyzing the clinical manifestations of this case and reviews relevant literature to improve our understanding of this disease in children.

The role of hypoxia-inducible factor 1 alpha (HIF-1α) modulation in heavy metal toxicity

Hypoxia-inducible factor 1 (HIF-1) is an oxygen-sensing transcriptional regulator orchestrating a complex of adaptive cellular responses to hypoxia. Several studies have demonstrated that toxic metal exposure may also modulate HIF-1α signal transduction pathway, although the existing data are scarce. Therefore, the present review aims to summarize the existing data on the effects of toxic metals on HIF-1 signaling and the potential underlying mechanisms with a special focus on prooxidant effect of the metals. The particular effect of metals was shown to be dependent on cell type, varying from down- to up-regulation of HIF-1 pathway. Inhibition of HIF-1 signaling may contribute to impaired hypoxic tolerance and adaptation, thus promoting hypoxic damage in the cells. In contrast, its metal-induced activation may result in increased tolerance to hypoxia through increased angiogenesis, thus promoting tumor growth and contributing to carcinogenic effect of heavy metals. Up-regulation of HIF-1 signaling is mainly observed upon Cr, As, and Ni exposure, whereas Cd and Hg may both stimulate and inhibit HIF-1 pathway. The mechanisms underlying the influence of toxic metal exposure on HIF-1 signaling involve modulation of prolyl hydroxylases (PHD2) activity, as well as interference with other tightly related pathways including Nrf2, PI3K/Akt, NF-κB, and MAPK signaling. These effects are at least partially mediated by metal-induced ROS generation. Hypothetically, maintenance of adequate HIF-1 signaling upon toxic metal exposure through direct (PHD2 modulation) or indirect (antioxidant) mechanisms may provide an additional strategy for prevention of adverse effects of metal toxicity.

Gpx4, Selenov, and Txnrd3 Are Three Most Testis-Abundant Selenogenes Resistant to Dietary Selenium Concentrations and Actively Expressed During Reproductive Ages in Rats

Almost all selenogenes are expressed in the testis, and those have the highest and constant expressions will be the primary candidates for functional analysis of selenium (Se) in male reproduction. This study aimed to profile the mRNA expressions of the testis-abundant selenogenes of rat models in responses to growth and dietary Se concentrations. Forty-eight weaning SD male rats were fed Se deficient basal diet (BD) for 5 weeks and then randomly grouped (n = 12/group) for being fed BD or BD plus 0.25, 3, or 5 mg Se/kg for 4 more weeks before sacrifice. Abundances of selenogenomic mRNAs in the liver and testis were determined with relative qPCR and those of the testis-abundant selenogenes in 13 kinds of tissues were assayed with a molecular beacon-based qPCR. Spatiotemporal expressions of rat selenogenome were also analyzed with the RNA-Seq transcriptomic data published by NCBI. mRNA abundances of glutathione peroxidase 4 (Gpx4), nuclear Gpx4 (nGpx4), selenoprotein V (Selenov), and thioredoxin reductase 3 (Txnrd3) in the testis were significantly higher than that in any other tissues (P < 0.05). Moreover, testicular mRNA abundances of Gpx4, Selenov, and Txnrd3 were not affected by levels of dietary Se supplementation (P > 0.05), and much higher at 6-21 weeks old than at 2 and 104 weeks old (P < 0.05). The result showed that Gpx4, Selenov, and Txnrd3 were most highly expressed in the testis of rats especially at reproductive ages and resistant to the impact of dietary Se levels, which suggested their specific importance in male reproduction.

[Correlation analysis of age and microbial characteristics in saliva and feces of high-risk population of upper gastrointestinal cancer]

Objective: To explore the correlation between age and diversity and microbial composition in saliva and feces microbiota in high-risk population of upper gastrointestinal cancer. Methods: Based on the national project on early diagnosis and early treatment of upper gastrointestinal cancer, 38 participants were enrolled in Linzhou in Henan province in August 2019. The participant information was collected by questionnaire. Saliva and feces specimens were collected from each participant for 16S rRNA sequencing and bioinformatics analysis. Spearman rank correlation was used to analyze the correlation between age and α diversity (Observed ASVs and Shannon index) and relative abundance of microbiota (phyla, genera, and species) in saliva and feces. Results: The median age (age range) of 38 participants was 54 (43-60) years old, and there were 16 males (42.1%). The Observed ASVs of saliva was negatively correlated with age (r_s=-0.35, P<0.05), but the observed ASVs of feces was not correlated with age. In saliva, the relative abundance of Treponema (r_s=‒0.44, P<0.05), Alloprevotella (r_s=‒0.42, P<0.05), and Porphyromonas (r_s=‒0.41,P<0.05) were significantly negatively correlated with age. At the species level, the relative abundance of Porphyromonas endodontalis, Alloprevotella tannerae, Haemophilus influenza, Moraxella bovoculi, Prevotella sp.oral clone ID019, and Prevotella sp.oral clone ASCG10 in saliva were significantly negatively correlated with age, and the r_s values were -0.50, -0.40, -0.38, -0.35, -0.33 and -0.33 (P<0.05), respectively. In feces, the relative abundance of Enterobacteria (r_s=-0.35, P<0.05), Escherichia (r_s=-0.33, P<0.05), and Bifidobacteria (r_s=0.33, P<0.05) were correlated with age. At the species level, the relative abundance of Romboutsia sedimentorum, Citrobacter murliniae, and bacteroides uniformis in feces were correlated with age, and the r_s values were -0.42, -0.37 and 0.36 (P<0.05), respectively. Conclusion: Age of the high-risk population of upper gastrointestinal cancer is correlated with the relative abundance of microbiota in saliva and feces.

Selenium-Enriched Cardamine violifolia Increases Selenium and Decreases Cholesterol Concentrations in Liver and Pectoral Muscle of Broilers

BACKGROUND

Supernutrition of selenium (Se) in an effort to produce Se-enriched meat may inadvertently cause lipid accumulation. Se-enriched Cardamine violifolia (SeCv) contains >80% of Se in organic forms.

OBJECTIVES

This study was to determine whether feeding chickens a high dose of SeCv could produce Se-biofortified muscle without altering their lipid metabolism.

METHODS

Day-old male broilers were allocated to 4 groups (6 cages/group and 6 chicks/cage) and were fed either a corn-soy base diet (BD, 0.13-0.15 mg Se/kg), the BD plus 0.5 mg Se/kg as sodium selenite (SeNa) or as SeCv, or the BD plus a low-Se Cardamine violifolia (Cv, 0.20-0.21mg Se/kg). At week 6, concentrations of Se and lipid and expression of selenoprotein and lipid metabolism-related genes were determined in the pectoral muscle and liver.

RESULTS

The 4 diets showed no effects on growth performance of broilers. Compared with the other 3 diets, SeCv elevated (P < 0.05) Se concentrations in the pectoral muscle and liver by 14.4-127% and decreased (P < 0.05) total cholesterol concentrations by 12.5-46.7% and/or triglyceride concentrations by 28.8-31.1% in the pectoral muscle and/or liver, respectively. Meanwhile, SeCv enhanced (P < 0.05) muscular α-linolenic acid (80.0%) and hepatic arachidonic acid (58.3%) concentrations compared with SeNa and BD, respectively. SeCv downregulated (P < 0.05) the cholesterol and triglyceride synthesis-related proteins (sterol regulatory element binding transcription factor 2 and diacylglycerol O-acyltransferase 2) and upregulated (P < 0.05) hydrolysis and β-oxidation of fatty acid-related proteins (lipoprotein lipase, fatty acid binding protein 1, and carnitine palmitoyltransferase 1A), as well as selenoprotein P1 and thioredoxin reductase activity in the pectoral muscle and/or liver compared with SeNa.

CONCLUSIONS

Compared with SeNa, SeCv effectively raised Se and reduced lipids in the liver and muscle of broilers. The effect was mediated through the regulation of the cholesterol and triglyceride biosynthesis and utilization-related genes.

[Progress in risk factors and potential biomarkers of esophageal squamous cell carcinoma]

Esophageal cancer is the main malignant cancer in China. In 2015, the incidence and mortality of esophageal cancer were 17.87 per 100 000 and 13.68 per 100 000, respectively, ranking 6th and 4th in the incidence and death. Esophageal squamous cell carcinoma (ESCC) is the main pathological type of esophageal cancer, accounting for 86.3% of new cases. ESCC's pathogenesis is still not clear and its related risk factors remain to be explored. There are no detection biomarkers that can be widely applied in the whole country nowadays. In order to provide a scientific basis for exploring the pathogenesis of ESCC and improve screening technology, this paper summarizes the research status of various risk factors and potential biomarkers of ESCC.

[Identification of the feature of immune cells infiltration in inherited renal carcinoma with von Hippel-Lindau syndrome]

Objective: To investigate the feature of immune cells infiltration in inherited renal carcinoma with von Hippel-Lindau (VHL) syndrome and their relationship with clinicopathological characteristics and prognosis. Methods: The samples were collected from patients with VHL syndrome renal carcinoma who were diagnosed and treated surgically at the Department of Urology, Peking University First Hospital from 2010 to 2019. RNA-Seq was performed on 6 pairs of VHL syndrome renal carcinoma and adjacent normal tissues. To identify the specific infiltrated immune cells, RNA-Seq data was converted into the infiltration data of 14 types of immune cells using the TIP tool. Immunohistochemical staining was used to verify the expression of the markers of these specific infiltrated immune cells in the paraffin sections of 54 paired VHL syndrome renal carcinoma and adjacent normal tissues, and to analyze their relationship with clinicopathological characteristics and prognosis. Results: Compared with adjacent normal tissues, CD4 Naive infiltration level was significantly down-regulated (0.289±0.009 vs 0.200±0.012,P<0.001) and CD4 Memory infiltration level was significantly up-regulated (0.123±0.014 vs 0.222±0.016,P<0.001) in VHL syndrome renal carcinoma. Immunohistochemical staining results showed that CD45RA (a CD4 Naive cell marker) expression was significantly reduced (50.9±1.9 vs 15.6±0.9,P<0.001) and CD45RO (a CD4 Memory cell marker) expression was significantly increased (22.2±1.1 vs 80.8±4.3,P<0.001) in VHL syndrome renal carcinoma. Besides, lower CD45RA expression and higher CD45RO expression were associated with higher histological grade, advanced tumor stage and shorter disease-free survival (all P<0.01). In addition, CD45RA expression was positively correlated with VHL expression (r=0.693 3, P<0.000 1) and CD45RO expression was negatively correlated with VHL expression (r=-0.609 0, P<0.000 1). Conclusions: This study found that CD4 Naive and CD4 Memory cells may be differentially infiltrated immune cells in VHL syndrome renal carcinoma, and their infiltration levels were associated with the expression of VHL and the prognosis of patients.

[Clinicopathological and prognostic characteristics of clear cell papillary renal cell carcinoma]

Objective: To analyze the epidemiological, clinicopathological and prognostic characteristics of clear cell papillary renal cell carcinoma (CCPRCC) based on Chinese patient population. Method: Patients with renal cell carcinoma diagnosed at Peking University First Hospital from June 2016 to June 2020 were included in this study based on the inclusion and exclusion criteria. All cases were grouped according to CCPRCC, clear cell renal cell carcinoma (ccRCC), and papillary renal cell carcinoma (pRCC), and the general clinical, postoperative pathological and follow-up data of the patients were retrospectively analyzed. Result: A total of 18 CCPRCC patients were enrolled in this study, accounting for 0.44% (18/4 110) of the postoperative pathologically confirmed renal cell carcinoma cases in our hospital during this time period. The age range of the included patients was 28-86 years old, with a median age of 49.5 years old. There were 11/18 males and 7/18 females. All CCPRCC patients had no family history of renal malignant tumors. Among them, only one patient with CCPRCC had related clinical symptoms, that was intermittent waist and abdomen pain, while the other 17 cases were found by physical examination without any related symptoms. Compared with ccRCC and pRCC, there was no significant difference in their end stage renal disease history(χ²_ccRCC=0.291, χ²_pRCC=1.161,all P>0.05). The maximum diameter of CCPRCC tumor was smaller than pRCC (χ²=-2.280,P =0.027) but not significantly different from ccRCC (χ²=-0.579,P =0.565). The majority of patients with CCPRCC were in pT1, their pathological stage was earlier than the other two types, and their overall survival was better than ccRCC and pRCC (P<0.05). Conclusion: CCPRCC is a type of renal cell carcinoma with unique epidemiology, clinicopathology and prognostic characteristics. Patients with this subtype have an earlier clinical stage and a better prognosis than ccRCC and pRCC.

Adipotropic effects of heavy metals and their potential role in obesity

Epidemiological studies demonstrated an association between heavy metal exposure and the incidence of obesity and metabolic syndrome. However, the particular effects of metal toxicity on adipose tissue functioning are unclear. Therefore, recent findings of direct influence of heavy metals (mercury, cadmium, and lead) and metalloid (arsenic) on adipose tissue physiology are discussed while considering existing gaps and contradictions. Here, we provide a literature review addressing adipose tissue as a potential target of heavy metal toxicity. Experimental in vivo studies demonstrated a significant influence of mercury, cadmium, lead, and arsenic exposure on body adiposity. In turn, in vitro experiments revealed both up- and downregulation of adipogenesis associated with aberrant expression of key adipogenic pathways, namely CCAAT/enhancer-binding protein (C/EBP) and peroxisome proliferator-activated receptor gamma (PPARγ). Comparison of the existing studies on the basis of dose and route of exposure demonstrated that the effects of heavy metal exposure on adipose tissue may be dose-dependent, varying from increased adipogenesis at low-dose exposure to inhibition of adipose tissue differentiation at higher doses. However, direct dose-response data are available in a single study only for arsenic. Nonetheless, both types of these effects, irrespective of their directionality, contribute significantly to metabolic disturbances due to dysregulated adipogenesis. Particularly, inhibition of adipocyte differentiation is known to reduce lipid-storage capacity of adipose tissue, leading to ectopic lipid accumulation. In contrast, metal-associated stimulation of adipogenesis may result in increased adipose tissue accumulation and obesity. However, further studies are required to reveal the particular dose- and species-dependent effects of heavy metal exposure on adipogenesis and adipose tissue functioning.

Associations between metabolic syndrome and four heavy metals: A systematic review and meta-analysis

Four most concerned heavy metal pollutants, arsenic, cadmium, lead, and mercury may share common mechanisms to induce metabolic syndrome (MetS). However, recent studies exploring the relationships between MetS and metal exposure presented inconsistent findings. We aimed to clarify the relationship between heavy metal exposure biomarkers and MetS using a meta-analysis and systematic review approach. Literature search was conducted in international and the Chinese national databases up to June 2020. Of selected studies, we extracted the relevant data and evaluated the quality of each study's methodology. We then calculated the pooled effect sizes (ESs), standardized mean differences (SMDs), and their 95% confidence intervals (CIs) using a random-effect meta-analysis approach followed by stratification analyses for control of potential confounders. Involving 55,536 participants, the included 22 articles covered 52 observational studies reporting ESs and/or metal concentrations on specific metal and gender. Our results show that participants with MetS had significantly higher levels of heavy metal exposure [pooled ES = 1.16, 95% CI: 1.09, 1.23; n = 42, heterogeneity I2 = 75.6%; and SMD = 0.22, 95% CI: 0.15, 0.29; n = 32, I2 = 94.2%] than those without MetS. Pooled ESs in the subgroups stratified by arsenic, cadmium, lead, and mercury were 1.04 (95% CI: 0.97, 1.10; n = 8, I2 = 61.0%), 1.10 (0.95, 1.27; 11, 45.0%), 1.21 (1.00, 1.48; 12, 82.9%), and 1.26 (1.06, 1.48; 11, 67.7%), respectively. Pooled ESs in the subgroups stratified by blood, urine, and the other specimen were 1.22 (95% CI: 1.08, 1.38; n = 26, I2 = 75.8%), 1.06 (1.00, 1.13; 14, 58.1%), and 2.41 (1.30, 4.43; 2, 0.0%), respectively. In conclusion, heavy metal exposure was positively associated with MetS. Further studies are warranted to examine the effects of individual metals and their interaction on the relationship between MetS and heavy metals.

Toxic metal exposure as a possible risk factor for COVID-19 and other respiratory infectious diseases

Multiple medical, lifestyle, and environmental conditions, including smoking and particulate pollution, have been considered as risk factors for COronaVIrus Disease 2019 (COVID-19) susceptibility and severity. Taking into account the high level of toxic metals in both particulate matter (PM2.5) and tobacco smoke, the objective of this review is to discuss recent data on the role of heavy metal exposure in development of respiratory dysfunction, immunotoxicity, and severity of viral diseases in epidemiological and experimental studies, as to demonstrate the potential crossroads between heavy metal exposure and COVID-19 severity risk. The existing data demonstrate that As, Cd, Hg, and Pb exposure is associated with respiratory dysfunction and respiratory diseases (COPD, bronchitis). These observations corroborate laboratory findings on the role of heavy metal exposure in impaired mucociliary clearance, reduced barrier function, airway inflammation, oxidative stress, and apoptosis. The association between heavy metal exposure and severity of viral diseases, including influenza and respiratory syncytial virus has been also demonstrated. The latter may be considered a consequence of adverse effects of metal exposure on adaptive immunity. Therefore, reduction of toxic metal exposure may be considered as a potential tool for reducing susceptibility and severity of viral diseases affecting the respiratory system, including COVID-19.

Genetic polymorphisms of superoxide dismutase 1 are associated with the serum lipid profiles of Han Chinese adults in a sexually dimorphic manner

Inspired by the mechanistic correlations between superoxide dismutase 1 (SOD1) and lipid metabolism, the associations of SOD1 single nucleotide polymorphisms (SNPs) with circulating lipid levels were explored. In 2621 Chinese Han adults, randomly recruited from a health examination center without organic diseases, cancers, and pregnancy, three tag SNPs, rs4998557, rs1041740, and rs17880487 selected by Haploview software were genotyped with a probe-based real-time quantitative PCR method. In both genders, most parameters of the dyslipidemia adults were inferior (P < 0.001) to those of the non-dyslipidemia adults, and genotype frequencies of rs4998557 and rs17880487 were significantly different (P < 0.05) between the normal and abnormal subgroups of total cholesterol (TC) or high-density lipoprotein cholesterol (HDLC). Adjusted for confounding factors, logistic regression analyses revealed that in males rs4998557A, rs1041740T, and rs17880487T reduced the risk of high TC and/or LDLC (P < 0.05), and rs4998557A and rs17880487T increased the risk of low HDLC (P < 0.05); but in females, none of the SNPs had associations with any of the lipid parameters (P > 0.05). Conclusively, characterized by a sexual dimorphism, the SOD1 polymorphisms were associated with the lipid disorders in the adult males but not females of the Chinese Han population.

[Introduction of the Prediction model Risk Of Bias ASsessment Tool: a tool to assess risk of bias and applicability of prediction model studies]

This paper introduceds the tool named as "Prediction model Risk Of Bias ASsessment Tool" (PROBAST) to assess the risk of bias and applicability in prediction model studies and the relevant items and steps of assessment. PROBAST is organized into four domains including participants, predictors, outcome and analysis. These domains contain a total of 20 signaling questions to facilitate structured judgment of risk of bias occurring in study design, conduct or analysis. Through comprehensive judgment, the risk of bias and applicability of original study is categorized as high, low or unclear. PROBAST enables a focused and transparent approach to assessing the risk of bias of studies that develop, validate, or update prediction models for individualized predictions. Although PROBAST was designed for systematic reviews, it can be also used more generally in critical appraisal of prediction model studies.

High serum concentration of selenium, but not calcium, cobalt, copper, iron, and magnesium, increased the risk of both hyperglycemia and dyslipidemia in adults: A health examination center based cross-sectional study

BACKGROUND

Metabolic disorders of glucose and lipid were associated with some mineral elements, and data were warranted from various contexts to make the association more explicit.

OBJECTIVE

To investigate the relationships between the serum concentrations of six mineral elements (calcium, cobalt, copper, iron, magnesium, and selenium) and the risk of hyperglycemia and dyslipidemia in adults.

METHODS

The basic information and the over-night fasting serum samples of adults were randomly collected at a health examination center. The serum concentrations of glucose and lipids were measured with an automatic biochemical analyzer, and the mineral elements were measured with an inductively coupled plasma mass spectrometer. Data were analyzed between the hyperglycemia group (HGg) and the normal glucose group (NGg) as well as between the dyslipidemia group (DLg) and the normal lipid group (NLg).

RESULTS

A total of 1466 adults aged 22-81 years (male/female = 1.8) were included, 110 in the HGg and 1356 in the NGg, or 873 in the DLg and 593 in the NLg. The serum element concentration medians [P50 (P25-P75)] significantly different between the HGg and the NGg were 0.83 (0.75-0.94) vs. 0.76 (0.68-0.87) mg/L for copper and 100 (90-110) vs. 94 (87-103) μg/L for selenium (P < 0.001), while those between the DLg and the NLg were 99 (92-110) vs. 97 (90-106) mg/L for calcium, 0.78 (0.69-0.88) vs. 0.75 (0.66-0.85) mg/L for copper, 1.7 (1.4-2.0) vs. 1.6 (1.3-2.0) mg/L for iron, 24 (22-28) vs. 23 (22-27) mg/L for magnesium, and 97 (89-106) vs. 92 (84-100) μg/L for selenium (P < 0.05). When the copper and selenium between the HGg and the NGg were analyzed by logistic regression with age, gender, body mass index, and mineral elements adjusted, only the highest quartile of selenium concentration had association with the increased risk of hyperglycemia [quartile (Q) 4 against Q1: OR = 2.9, 95 % CI = 1.5-5.5, P < 0.001). When the five differed mineral elements between the DLg and the NLg were similarly analyzed, only iron and selenium had associations with the increased risk of dyslipidemia (e.g., Q4 against Q1: OR = 1.4, 95 % CI = 1.1-2.0 for iron and OR = 2.9, 95 % CI = 2.1-4.0 for selenium, P < 0.05).

CONCLUSION

In contrast to those of calcium, cobalt, copper, iron, and magnesium, the higher serum concentration of selenium increased the risk of both hyperglycemia and dyslipidemia in the study population of adult Chinese.

[Status of non-steroidal anti-inflammatory drugs use in areas with a high incidence of upper gastrointestinal cancer in China: a multi-center cross-sectional survey]

Objective: To describe the status of non-steroidal anti-inflammatory drugs (NSAIDs) use in areas with a high incidence of upper gastrointestinal cancer in China. Methods: This study was based on the National Key Research and Development Program of "National Precision Medicine Cohort of Esophageal Cancer" and "Study on Identification and Prevention of High-risk Populations of Gastrointestinal Malignancies (Esophageal cancer, Gastric cancer and Colorectal cancer)" . From January 2017 to August 2018, 212 villages or communities with a high incidence of esophageal cancer or gastric cancer were selected from 12 regions in 6 provinces. A total of 35 910 residents aged between 40 and 69 years old who met the inclusion criteria and signed the informed consent were investigated and enrolled in this study. The use of NSAIDs, demographic characteristics, health-related habits, height, weight, and blood pressure were collected by the questionnaire and physical examination. The status of main NSAIDs (aspirin, acetaminophen and ibuprofen) use with the difference varying in genders, age groups and regions were analyzed by using χ(2) test and Cochran-Armitage trend analysis method. Results: Of 35 910 subjects, the mean age was (54.6±7.1) years old and males accounted for 43.42% (15 591). The overall prevalence of NSAIDs intake was 4.56% (1 638), but it significantly varied in different provinces (P<0.001). The overall prevalence of NSAIDs intake was 4.87% (1 750) in females, which was significantly higher than that in males 4.24% (1 524) (P<0.001). The prevalence of NSAIDs intake increased with age (P for trend <0.001). As the frequency of NSAIDs intake increased, the incidence of gastrointestinal symptoms, gastrointestinal ulcers and black stools increased (P for trend <0.05 for all). Conclusion: The use of NSAIDs is prevalent in some areas with a high incidence of upper gastrointestinal cancer in China. The increased use of NSAIDs may lead to more adverse effects related to the gastrointestinal tract.

[Dentification and correction of the lead-time bias and length bias in cancer screening studies]

Lead-time bias and length bias were common systematic errors in observational screening studies, which might be a common cause of overstating or distorting the true screening effects. One of key concerns in observational screening studies was how to estimate the screening effects based on the consideration of these two biases. This paper illustrated how to identify and correct the lead-time bias using the tumor volume doubling time and the non-homogeneous Poisson process, and how to correct the length bias using a weighted method. The application conditions of each method were also discussed to present several useful toolboxes to correct the lead-time bias and length bias appropriately and evaluate the effectiveness of the cancer screening program accurately.

[Clinical application and optimization of HEAD-US quantitative ultrasound assessment scale for hemophilic arthropathy]

目的

评价HEAD-US评估量表在血友病性关节病临床应用的可行性，提出优化的超声评估量表HEAD-US-C。

方法

2015年7月至2017年8月期间，91例血友病患者接受1 035例次关节超声检查，分别采用Melchiorre、HEAD-US、HEAD-US-C量表进行评分，分析与血友病关节健康评分量表（HJHS）评分之间的相关性并比较上述量表评价血友病性关节病的敏感性。

结果

91例患者均为男性，中位年龄16（4~55）岁，血友病A 86例，血友病B 5例。1 035例次关节检查Melchiorre、HEAD-US、HEAD-US-C量表的评分[M（P₂₅, P₇₅）]分别为2（0,6）、1（0,5）、2（0,6），均与HJHS评分之间存在相关关系（相关系数分别为0.747、0.762、0.765，P值均<0.001）。Melchiorre、HEAD-US-C、HEAD-US评分量表的阳性率分别为63.0%（95%CI 59.7%~65.9%）、59.5%（95%CI 56.5%~62.4%）、56.6%（95%CI 53.6%~59.6%），差异有统计学意义（P<0.001）。336例次无症状关节（HJHS评分0分）Melchiorre、HEAD-US-C、HEAD-US评分量表的阳性率分别为25.0%（95%CI 20.6%~29.6%）、17.0%（95%CI12.6%~21.1%）、11.9%（95%CI 8.4%~15.7%）（P<0.001）。40例有关节出血症状的血友病患者（107例次）关节出血前、出血后超声评分差异有统计学意义（P<0.05）。HEAD-US-C与HEAD-US评分的变化幅度比较，差异有统计学意义（P<0.001）。

结论

与Melchiorre比较，HEAD-US、HEAD-US-C与HJHS之间具有相似的良好的相关性。HEAD-US-C评分量表较HEAD-US更为敏感，尤其适合亚临床状态血友病性关节病的评估。

[A brief review on studies of the Chinese Red Army medical aid]

The Chinese Red Army medical aid not only has collected and collated existing data but also has studied related contents.With regard to the collection of data and materials, there were both medical-health thematic data and medical-health data covered by the comprehensive data, reprinted and translated of documentary data.With respect to medical aid research, there were both comprehensive and thematic studies. Among thematic studies, included medical institutions, health teams, methodology, role of health work, medical aid with traditional Chinese Medicine, and the research of Red Army medical staff.Looking forward to the future research, we should focus on literature mining and data expansion, innovation of research perspective, integrated application of multidisciplinary research methods, diversity of research subjects and the "normalization" of research results.

The GC2 haplotype of the vitamin D binding protein is a risk factor for a low plasma 25-hydroxyvitamin D concentration in a Han Chinese population

Background

The GC haplotype of the vitamin D binding protein (encoded by the GC gene) might be a risk factor to the vitamin D (VD) nutritional status for many populations, while evidences from the Chinese Han population are sparse. We test the association between vitamin D binding protein genotypes and VD status as well as the metabolic parameters of glucose and lipids in a Han Chinese population.

Methods

In a cross-sectional study conducted at a health examination centre (registered in ClinicalTrials.gov as QLS2013), 2641 adults were included and grouped according to their plasma 25-hydroxyvitamin D (25OHD) concentrations as VD deficient (VDD), insufficient (VDI), or sufficient (VDS). The rs7041 and rs4588 genotypes were analysed with a molecular beacon-based qPCR method using blood samples.

Results

Plasma 25OHD concentrations were lower in the GC2/2, rs7041T/T, and rs4588A/A genotypes than the GC1f/1s, rs7041G/T, and rs4588C/C genotypes (P <  0.05). After adjusting for confounders, the GC2 haplotype increased the risk of low VD status (P <  0.05) in both genders. More genotypic models revealed the negative contributions of rs4588A than rs7041T to low VD status (P <  0.05). The combined rates of VDD and VDI were 80.2% in males and 86.1% in females. Compared with VDI, VDS, or both, VDD showed higher plasma concentrations of fasting blood glucose, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglycerides in males (P <  0.05); however, no significant differences were found with regard to these parameters between the subgroups defined by the GC genotypes (P > 0.05).

Conclusions

In a Han Chinese population, the GC2 haplotype or more exactly rs4588A is a risk factor for low VD status but is not associated with glucose and lipid metabolic disorders, which are inversely correlated with the circulating 25OHD concentration in males.

Trial registration

The study was retrospectively registered in January 2018 as NCT03406234 in the ClinicalTrials.gov online system.

Electronic supplementary material

The online version of this article (10.1186/s12986-019-0332-0) contains supplementary material, which is available to authorized users.

Evolution, regulation, and function of porcine selenogenome

Much less research on regulation and function of selenoproteins has been conducted in domestic pigs than in rodents or humans, although pigs are an excellent model of human nutrition and medicine and pork is a widely consumed meat in the world. Phylogenetically, the 25 identified porcine selenoproteins fell into two primitive groups, and might be further divided into three parallel branches. Despite a high similarity to that of humans and rodents, the porcine selenoproteome exhibited the closest evolutionary relationship with that of sheep and cattle among eight domestic species. Expression (mRNA, protein, and/or enzyme activity) of 2/3 of the 25 porcine selenoproteins in various tissues of pigs was affected by dietary Se intakes, and 14 of them showed responses to a high fat diet. When dietary Se deficiency mainly down-regulated the expression of selected selenoproteins, dietary Se excess exerted rather diverse effects on their expression. Overdosing pigs with dietary Se induced hyperinsulinemia, along with lipid accumulation and protein increase, in the liver and muscle by affecting key genes and(or) proteins involved in the metabolisms of glucose, lipid, and protein. In conclusion, expression of porcine selenoproteins was highly responsive to dietary Se and fat intakes, and was involved in body glucose, lipid, and protein metabolism as those of rodents and humans.

Role of glutathione peroxidase 1 in glucose and lipid metabolism-related diseases

Glutathione peroxidase 1 (GPX1) is a selenium-dependent enzyme that reduces intracellular hydrogen peroxide and lipid peroxides. While past research explored regulations of gene expression and biochemical function of this selenoperoxidase, GPX1 has recently been implicated in the onset and development of chronic diseases. Clinical data have shown associations of human GPX1 gene variants with elevated risks of diabetes. Knockout and overexpression of Gpx1 in mice may induce types 1 and 2 diabetes-like phenotypes, respectively. This review assembles the latest advances in this new field of selenium biology, and attempts to postulate signal and molecular mechanisms mediating the role of GPX1 in glucose and lipid metabolism-related diseases. Potential therapies by harnessing the beneficial effects of this ubiquitous redox-modulating enzyme are briefly discussed.

[An analysis of the new "three tubes" method in the treatment of spontaneous esophageal rupture]

To investigate the clinical efficacy, feasibility and safety of new "three tubes" method in the treatment of spontaneous esophageal rupture. A total of 22 patients with spontaneous esophageal rupture were retrospectively analyzed. Through the new "three tubes" method of treatment, patients achieved leak cured with reduced hospital stay, less medical expenses and early resumption of oral diet. The new "three tubes" method for spontaneous esophageal rupture has the advantages of easy handling, minimal invasion, few complication and exact curative effect.

Dietary Selenium Deficiency or Excess Reduces Sperm Quality and Testicular mRNA Abundance of Nuclear Glutathione Peroxidase 4 in Rats

Background: Glutathione peroxidase (GPX) 4 and selenoprotein P (SELENOP) are abundant, and several variants are expressed in the testis.Objective: We determined the effects of dietary selenium deficiency or excess on sperm quality and expressions of GPX4 and SELENOP variants in rat testis and liver.Methods: After weaning, male Sprague-Dawley rats were fed a Se-deficient basal diet (BD) for 5 wk until they were 9 wk old [mean ± SEM body weight (BW) = 256 ± 5 g]. They were then fed the BD diet alone (deficient) or with 0.25 (adequate), 3 (excess), or 5 (excess) mg Se/kg for 4 wk. Testis, liver, blood, and semen were collected to assay for selenoprotein mRNA and protein abundances, selenium concentration, GPX activity, 8-hydroxy-deoxyguanosine concentration, and sperm quality.Results: Dietary selenium supplementations elevated (P < 0.05) tissue selenium concentrations and GPX activities. Compared with those fed BD + 0.25 mg Se/kg, rats fed BD showed lower (P < 0.05) BW gain (86%) and sperm density (57%) but higher (P < 0.05) plasma 8-hydroxy-deoxyguanosine concentrations (189%), and nonprogressive sperm motility (4.4-fold). Likewise, rats fed BD + 5 mg Se/kg had (P = 0.06) lower BW gain and higher (1.9-fold) sperm deformity rates than those in the selenium-adequate group. Compared with the selenium-adequate group, dietary selenium deficiency (BD) or excess (BD + 3 or 5 mg Se/kg) resulted in 45-77% lower (P < 0.05) nuclear Gpx4 (nGpx4) mRNA abundance in the testis. Rats fed BD had lower (P < 0.05) mRNA levels of 2 Selenop variants in both testis and liver than those in the other groups. Testicular SELENOP was 155-170% higher (P < 0.05) in rats fed BD + 5 mg Se/kg and hepatic c/mGPX4 was 13-15% lower (P < 0.05) in rats fed BD than in the other groups.Conclusions: The mRNA abundance of rat testicular nGPX4 responded to dietary selenium concentrations in similar ways to sperm parameters and may be used as a sensitive marker to assess appropriate Se status for male function.

[Effectiveness of unilateral selective laser trabeculoplasty for primary open angle glaucoma]

OBJECTIVE

To study the effectiveness of unilateral selective laser trabeculoplasty (SLT) on the both eyes of patients with primary open-angle glaucoma (POAG).

METHODS

This was a self-controlled clinical study. Thirty-two patients of 32 eyes with OAG who used same anti-glaucoma medications for both eyes were included aat the Department of Ophthalmology Peking University third Hospital from February 2010 to April 2014. SLT was performed for the poorly controlled eye for each patient. Patients were examined before operation and 1 hour, 1 week, 1 month, 3 months and 6 months after operation. The intraocular pressure was examined after 1 hour of SLT. The rest time points were examined by visual acuity, intraocular pressure (IOP), slit lamp microscope, fundus ophthalmoscope and visual field. The paired t test (Bonferroni) was used to compare the IOP at each time point after SLT with the baseline IOP before SLT. Single factor analysis of variance was used to compare the percentage of IOP drop. Linear correlation analysis was used to analyze the amplitude of the decrease of IOP between treated eyes and untreated eyes at 6-month post-operatively and analyze the IOP between preoperative eyes and 6-month post-operative eyes. The magnitude of the decrease of IOP in patients with glaucoma medication and 6 months after surgery was analyzed. We also analyzed the types of antiglaucoma medications and IOP reductions range for 6 month after SLT.

RESULTS

The preoperative mean IOP was (18.9±2.5) mmHg (1 mmHg=0.133 kPa) in the treated eye of patients with OAG. Mean IOP reduction for 1 week, 1, 3, and 6 months after SLT were (1.7±2.9) mmHg, (2.5±2.5) mmHg, (3.5±2.8) mmHg, (3.4±2.5) mmHg and the percentage of IOP reduction were (8±16) %, (13±13) % (18±14) %, (18±12) % respectively (compared with the baseline, P< 0.05) . With the success criteria of IOP reduction ≥3.0 mmHg or ≥20%, the success rate of SLT in the treated eye after 1 week, 1, 3, 6 months was 38%, 52%, 50% and 60% respectively. For the untreated fellow eyes, the preoperative mean IOP was (17.3±2.4) mmHg. Mean IOP reduction for 1 week, 1month, 3 month, and 6 month after SLT were (1.1±2.0) mmHg, (1.0±2.7) mmHg, (2.6±2.2) mmHg and (2.5±2.2) mmHg respectively (compared with the baseline, P<0.05) . There was a positive correlation between preoperative IOP and IOP reduction either in the treated or in the untreated eyes at 6-month post-SLT (R=0.63, P<0.01; R=0.60, P<0.01) . There was a positive correlation in IOP reduction between treated eyes and untreated eyes at 6-month post-operative (R=0.66, P<0.01). All patients didn't need further treatment such as another laser treatment or surgery. Anti-glaucoma medications were remained unchanged after SLT.

CONCLUSIONS

In poorly anti-glaucoma medication controlled Chinese POAG eyes with mean IOP about 18.0 mmHg, unilateral STL can reduce the IOP about 18% at 6-month post-operative for the treated eyes. There was also a continuous IOP reduction effects for the fellow eyes.(Chin J Ophthalmol, 2016, 52: 410-415).

Expression of Selenoprotein Genes Is Affected by Obesity of Pigs Fed a High-Fat Diet

BACKGROUND

Relations of the 25 mammalian selenoprotein genes with obesity and the associated inflammation remain unclear.

OBJECTIVE

This study explored impacts of high-fat diet-induced obesity on inflammation and expressions of selenoprotein and obesity-related genes in 10 tissues of pigs.

METHODS

Plasma and 10 tissues were collected from pigs (n = 10) fed a corn-soy-based control diet or that diet containing 3-7% lard from weanling to finishing (180 d). Plasma concentrations (n = 8) of cytokines and thyroid hormones and tissue mRNA abundance (n = 4) of 25 selenoprotein genes and 16 obesity-related genes were compared between the pigs fed the control and high-fat diets. Stepwise regression was applied to analyze correlations among all these measures, including the previously reported body physical and plasma biochemical variables.

RESULTS

The high-fat diet elevated (P < 0.05) plasma concentrations of tumor necrosis factor α, interleukin-6, leptin, and leptin receptor by 29-42% and affected (P < 0.05-0.1) tissue mRNA levels of the selenoprotein and obesity-related genes in 3 patterns. Specifically, the high-fat diet up-regulated 12 selenoprotein genes in 6 tissues, down-regulated 13 selenoprotein genes in 7 tissues, and exerted no effect on 5 genes in any tissue. Body weights and plasma triglyceride concentrations of pigs showed the strongest regressions to tissue mRNA abundances of selenoprotein and obesity-related genes. Among the selenoprotein genes, selenoprotein V and I were ranked as the strongest independent variables for the regression of phenotypic and plasma measures. Meanwhile, agouti signaling protein, adiponectin, and resistin genes represented the strongest independent variables of the obesity-related genes for the regression of tissue selenoprotein mRNA.

CONCLUSIONS

The high-fat diet induced inflammation in pigs and affected their gene expression of selenoproteins associated with thioredoxin and oxidoreductase systems, local tissue thyroid hormone activity, endoplasmic reticulum protein degradation, and phosphorylation of lipids. This porcine model may be used to study interactive mechanisms between excess fat intake and selenoprotein function.

Prevention of Aflatoxin B1 Hepatoxicity by Dietary Selenium Is Associated with Inhibition of Cytochrome P450 Isozymes and Up-Regulation of 6 Selenoprotein Genes in Chick Liver

BACKGROUND

The involvement of cytochrome P450 (CYP450) isozymes and the selenogenome in selenium-mediated protection against aflatoxin B1 (AFB1)-induced adverse effects in broilers remains unclear.

OBJECTIVE

This study was designed first to determine whether selenium could reduce AFB1-induced hepatotoxic effects and then to determine whether these effects were due to changes in the CYP450 isozymes and selenogenome expression in the liver of chicks.

METHODS

Male avian broilers (aged 120 d) were allocated to 4 groups with 5 replicates of 6 birds to be included in a 2-by-2 factorial trial in which the main factors included supplementation of AFB1 (<5 compared with 100 μg/kg) and selenium (0.2 compared with 0.5 mg/kg) in a corn/soybean-based diet for 4 wk. Serum biochemistry, hepatic histology, and mRNA and/or activities of hepatic antioxidant enzymes, CYP450 isozymes, and 26 selenoproteins were analyzed at week 2 and/or 4.

RESULTS

Administration of AFB1 induced liver injury, decreasing (P < 0.05) total protein and albumin concentrations by 33.3-43.8% and increasing (P < 0.05) alanine aminotransferase and aspartate aminotransferase activities by 26.0-33.8% in serum, and induced hepatic necrosis and bile duct hyperplasia at week 2. AFB1 also decreased (P < 0.05) hepatic activities of glutathione peroxidase (GPX), thioredoxin reductase (TXNRD), and catalase, and the glutathione concentration by 13.1-59.9% and increased (P < 0.05) malondialdehyde, 8-hydroxydeoxyguanosine and exo-AFB1-8,9-epoxide (AFBO) DNA concentrations by 17.9-1200%. In addition, the mRNA and activity of enzymes responsible for the bioactivation of AFB1 into AFBO, which included CYP450 A1, 1A2, 2A6, and 3A4, were significantly induced (P < 0.05) by 29.2-271% in liver microsomes after 2-wk exposure to AFB1. These alterations induced by AFB1 were prevented by selenium supplementation. Dietary selenium supplementation increased (P < 0.05) mRNA and/or activities of 6 selenoprotein genes (Gpx3, Txnrd1, Txnrd2, Txnrd3, iodothyronine deiodinase 2, and selenoprotein N) in the liver of AFB1-treated groups at week 2.

CONCLUSIONS

Dietary selenium protected chicks from AFB1-induced liver injury, potentially through the synergistic actions of inhibition of the pivotal CYP450 isozyme-mediated activation of AFB1 to toxic AFBO, and increased antioxidant capacities by upregulation of selenoprotein genes coding for antioxidant proteins.

Alteration of lipid profile in subclinical hypothyroidism: a meta-analysis

BACKGROUND

Previous studies yielded controversial results about the alteration of lipid profiles in patients with subclinical hypothyroidism. We performed a meta-analysis to investigate the association between subclinical hypothyroidism and lipid profiles.

MATERIAL AND METHODS

We searched PubMed, Cochrane Library, and China National Knowledge Infrastructure articles published January 1990 through January 2014. Dissertation databases (PQDT and CDMD) were searched for additional unpublished articles. We included articles reporting the relationship between subclinical hypothyroidism and at least 1 parameter of lipid profiles, and calculated the overall weighted mean difference (WMD) with a random effects model. Meta-regression was used to explore the source of heterogeneity among studies, and the Egger test, Begg test, and the trim and fill method were used to assess potential publication bias.

RESULTS

Sixteen observational studies were included in our analysis. Meta-analysis suggested that the serum total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and total triglyceride levels were significantly increased in patients with subclinical hypothyroidism compared with euthyroidism individuals; the WMD were 12.17 mg/dl, 7.01 mg/dl, and 13.19 mg/dl, respectively (P<0.001 for all). No significant difference was observed for serum high-density lipoprotein cholesterol (HDL-C). Match strategy was the main source of heterogeneity among studies in TC and LDL-C analysis. Potential publication bias was found in TC and LDL-C analysis by the Egger test or Begg test and was not confirmed by the trim and fill method.

CONCLUSIONS

Subclinical hypothyroidism may correlate with altered lipid profile. Previous studies had limitations in the control of potential confounding factors and further studies should consider those factors.

A high-selenium diet induces insulin resistance in gestating rats and their offspring

Although supranutrition of selenium (Se) is considered a promising anti-cancer strategy, recent human studies have shown an intriguing association between high body Se status and diabetic risk. This study was done to determine if a prolonged high intake of dietary Se actually induced gestational diabetes in rat dams and insulin resistance in their offspring. Forty-five 67-day-old female Wistar rats (n=15/diet) were fed a Se-deficient (0.01 mg/kg) corn-soy basal diet (BD) or BD+Se (as Se-yeast) at 0.3 or 3.0mg/kg from 5 weeks before breeding to day 14 postpartum. Offspring (n=8/diet) of the 0.3 and 3.0mg Se/kg dams were fed with the same respective diet until age 112 days. Compared with the 0.3mg Se/kg diet, the 3.0mg/kg diet induced hyperinsulinemia (P<0.01), insulin resistance (P<0.01), and glucose intolerance (P<0.01) in the dams at late gestation and/or day 14 postpartum and in the offspring at age 112 days. These impairments concurred with decreased (P<0.05) mRNA and/or protein levels of six insulin signal proteins in liver and muscle of dams and/or pups. Dietary Se produced dose-dependent increases in Gpx1 mRNA or GPX1 activity in pancreas, liver, and erythrocytes of dams. The 3.0mg Se/kg diet decreased Selh (P<0.01), Sepp1 (P=0.06), and Sepw1 (P<0.01), but increased Sels (P<0.05) mRNA levels in the liver of the offspring, compared with the 0.3mg Se/kg diet. In conclusion, supranutrition of Se as a Se-enriched yeast in rats induced gestational diabetes and insulin resistance. Expression of six selenoprotein genes, in particular Gpx1, was linked to this metabolic disorder.

Effects of microwave radiation and conductive heating on Tribolium castaneum microstructure

Microwave radiation and conductive heating were used to completely kill adult Tribolium castaneum (Coleoptera: Tenebrionidae) in wheat flour to protect the flour during storage without significantly effecting its quality. The microstructure of T. castaneum was analyzed to reveal the mechanisms leading to death under microwave and heat treatments. Microwave radiation and conductive heating had different effects on the microstructure of the cuticle of adult T. castaneum and on the ultrastructure of the cells of the epidermis, fat body, and midgut. Both treatments caused a large cavity to appear in the nucleus and the disappearance of mitochondria and the Golgi apparatus. After microwave treatment, there was little change in the surface microstructure but the epidermis was of uneven thickness and the four outer layers of the cuticle were thinner. Nuclear size was essentially unchanged, but fat body cells were fewer and coalesced together. In contrast, conductive heating led to a disordered arrangement of cells on the surface of T. castaneum and indistinct boundaries between layers of the cuticle. The nuclei were enlarged and the fat body cells noticeably fewer and indistinct with a scattered distribution. Thus, microwave treatment produced less severe effects on the surface microstructure and cellular ultrastructure of T. castaneum than did conductive heating. It is concluded that these cellular and surface changes were responsible for the death of T. castaneum.

Enhanced water-holding capacity of meat was associated with increased Sepw1 gene expression in pigs fed selenium-enriched yeast

To study the effect of selenium-enriched yeast (SeY) level on selenoprotein genes expression and the relation between gene expression and antioxidant status and meat quality, 30 selenium (Se)-depleted pigs (7-week old, 10.30±0.68 kg) were randomly divided into 3 groups and fed a basal diet plus 0, 0.3 and 3.0 mg Se/kg as SeY for 8 weeks. Results showed that dietary SeY supplementation improved the antioxidant status in muscle. The increased levels of SeY decreased (P<0.05) the drip loss and the concentration of thiobarbituric acid reactive substances in the muscle and meat. However, increased dietary SeY intake quadratically increased (P<0.01) the mRNA level of Sepw1 gene among the 12 selenoprotein genes examined in muscle. Statistical analysis showed drip loss was negatively correlated with the mRNA level of Sepw1 gene. These suggested that the enhanced water-holding capacity of meat was associated with the increased expression of Sepw1 gene.

Selenoprotein gene expression in thyroid and pituitary of young pigs is not affected by dietary selenium deficiency or excess

Expression and function of selenoproteins in endocrine tissues remain unclear, largely due to limited sample availability. Pigs have a greater metabolic similarity and tissue size than rodents as a model of humans for that purpose. We conducted 2 experiments: 1) we cloned 5 novel porcine selenoprotein genes; and 2) we compared the effects of dietary selenium (Se) on mRNA levels of 12 selenoproteins, activities of 4 antioxidant enzymes, and Se concentrations in testis, thyroid, and pituitary with those in liver of pigs. In Experiment 1, porcine Gpx2, Sephs2, Sep15, Sepn1, and Sepp1 were cloned and demonstrated 84-94% of coding sequence homology to human genes. In Experiment 2, weanling male pigs (n = 30) were fed a Se-deficient (0.02 mg Se/kg) diet added with 0, 0.3, or 3.0 mg Se/kg as Se-enriched yeast for 8 wk. Although dietary Se resulted in dose-dependent increases (P < 0.05) in Se concentrations and GPX activities in all 4 tissues, it did not affect the mRNA levels of any selenoprotein gene in thyroid or pituitary. Testis mRNA levels of Txnrd1 and Sep15 were decreased (P < 0.05) by increasing dietary Se from 0.3 to 3.0 mg/kg. Comparatively, expressions of Gpx2, Gpx4, Dio3, and Sep15 were high in pituitary and Dio1, Sepp1, Sephs2, and Gpx1 were high in liver. In conclusion, the mRNA abundances of the 12 selenoprotein genes in thyroid and pituitary of young pigs were resistant to dietary Se deficiency or excess.

[Evaluation on the dietary iron absorption by young Tibetan men using stable isotopic tracer]

OBJECTIVE

The study was aimed to evaluate the iron absorption in the Tibetan man's diet using the stable isotopic iron, and present a reference to improve the dietary iron absorption for Chinese.

METHODS

In the study conducted on the spot of high altitude (> 3500m), the iron tracer (FeSO4 enriched with 57Fe) and the recovery indicator dysprosium (Dy) were orally administrated to 16 young Tibetan men, and their feces were sampled. The ratios of 57Fe/56Fe in fecal samples was determined by inductively coupled plasma mass spectrometry, and then the iron absorption was calculated based on the principle of isotope dilution.

RESULTS

The rate of dietary iron absorption in young Tibetan men was 13.4% +/- 6.4% with good linear correlation between daily fecal excretions of iron tracer and Dy.

CONCLUSION

Dy had the same behavior as non-absorbed iron tracer in the digestive tract and the recovery of Dy may indicate the completeness of fecal collection. Dietary iron absorption in the adult Tibetan man was relatively high.

[Cloning and characterization of three novel genes encoding transmembrane proteins of Schistosoma japonicum]

OBJECTIVE

To clone and analyze novel antigen molecules of Schistosoma japonicum (Sj), and to provide effective vaccine candidate antigens against schistosomiasis japonica.

METHODS

Sj adult cDNA library was screened using sera of mice infected with Trichinella spiralis (Ts) and the inserts of positive clones were specifically amplified by PCR. The positive clones were sequenced and the sequence data were analyzed using Nucleotide BLAST software of NCBI and Expert Protein Analysis System of Swiss Institute of Bioinformatics.

RESULTS

Nine positive clones were obtained after three rounds of immunoscreening. The size of these inserts ranged from 0.6 kb to 2.1 kb. Among five novel genes, Sj-Ts1, Sj-Ts3 and Sj-Ts5 (GenBank accession number: AY005816, AF299080 and AY024352, respectively) encode trans-membrane proteins with 83, 83 and 233 amino acids, respectively. Sj-Ts1 protein predicted contains one possible trans-membrance helix, one N-myristoylation site, two phosphorylation sites for protein kinase C and one for tyrosine kinase, Sj-Ts3 protein contains two possible transmembrance helices and one casein kinase II phosphorylation site, whereas Sj-Ts5 protein has five possible transmembrance helices, one N-glycosylation site, one N-myristoylation site, two phosphorylation sites for cAMP- and cGMP-dependent protein kinase and four for protein kinase C and one for casein kinase II.

CONCLUSION

Three novel genes encoding three transmembrane proteins might be developed as new vaccine candidates against Sj infection.

[Evaluation of Schistosoma japonicum tegumental membrane antigen (SjMAg) in immunodiagnosis and efficacy assessment]

OBJECTIVE

To evaluate the specificity and sensitivity of SjMAg in detecting specific antibodies in sera of patients with schistosomiasis japonica and in assessing therapeutic efficacy.

METHODS

SjMAg-ELISA was used to determine the specific IgG and IgG4 in sera of patients with schistosomiasis japonica at different time points after chemotherapy.

RESULTS

SjMAg-ELISA was as sensitive and specific as SEA-ELISA. The negative conversion rate of IgG detected by SjMAg-ELISA 12 months after treatment was 80.0%, being significantly higher than 43.3% by SEA-ELISA. The negative conversion rate of IgG4 detected by SjMAg-ELISA 12 months after treatment was 93.3%, being significantly higher than 60.0% by SEA-ELISA. The negative conversion rates of IgG and IgG4 2 yr after treatment were 92.9% and 97.6% respectively.

CONCLUSION

SjMAg-ELISA is comparable to SEA-ELISA in diagnosing schistosomiasis japonica and is more effective in assessing therapeutic efficacy.

A catalogue of molecular, physiological and symbiotic properties of soybean-nodulating rhizobial strains from different soybean cropping areas of China

We have analysed 198 fast-growing soybean-nodulating rhizobial strains from four different regions of China for the following characteristics: generation time; number of plasmids; lipopolysaccharide (LPS), nodulation factors (LCOs) and PCR profiles; acidification of growth medium; capacity to grow at acid, neutral, and alkaline pH; growth on LC medium; growth at 28 and 37 degrees C; melanin production capacity; Congo red absorption and symbiotic characteristics. These unbiased analyses of a total subset of strains isolated from specific soybean-cropping areas (an approach which could be called "strainomics") can be used to answer various biological questions. We illustrate this by a comparison of the molecular characteristics of five strains with interesting symbiotic properties. From this comparison we conclude, for instance, that differences in the efficiency of nitrogen fixation or competitiveness for nodulation of these strains are not apparently related to differences in Nod factor structure.

[Immunoscreening of Schistosoma japonicum adult worm cDNA library by sera from rabbits vaccinated with ultraviolet-attenuated cercariae]

OBJECTIVE

To find out the major antigenic molecules of radiation-attenuated cercariae, and provide some useful candidate antigens for developing schistosomiasis vaccine.

METHODS

Schistosoma japonicum (Sj) adult worm cDNA library was screened by sera of rabbits vaccinated with ultraviolet-attenuated cercariae, and the inserts of positive clones were specifically amplified by PCR and sequenced.

RESULTS

Ten positive clones were obtained after three rounds of screening, and the size of Sj cDNA fragments of the positive clones ranged from 1.5 kb to 1.8 kb. Five partial sequences were got after preliminary sequencing. Two of them had significantly homology with Sj dynein light chain 5(DLC 5) gene and Sj mitochondrial gene, respectively, and the others were identified as partial sequences of novel genes for they showed only partial homology with non-schistosome genes or other organism in the database.

CONCLUSIONS

The positive clones may be the genes encoding the antigens that can elicit protective immunity against Sj.

[Experimental study on immunization of mice with nucleic acid vaccine Sj31BIN combining IL-12 against Schistosoma japonicum]

Based on the anti-fecundity effect of Schistosoma japonicum nucleic acid vaccine Sj31BIN, we combined Sj31BIN with IL-12 in vaccination of mice to explore the role of IL-12 as an adjuvant. The result showed that immunization of the mice with Sj31BIN + IL-12 led to a significant decrease in adult worm recovery, a liver egg count reduction of 59.74%, an intestine egg count reduction of 59.60% and a liver surface egg granuloma reduction of 71.3%. In addition, vaccination of the mice with IL-12 alone also led to some but not significant decrease in adult worm recovery and the egg counts. It is concluded that Sj31BIN plus IL-12 induces significant anti-fecundity immunity.

[Preliminary report on immunoscreening of Schistosoma japonicum adult worm cDNA library by sera from infected Microtus fortis]

Microtus fortis (Mf) is resistant to Schistosoma japonicum (Sj) infection. To explore if Mf responses to special Sj antigens after infection, Sj adult worm cDNA library was screened with sera from infected Mf. Twelve positive clones were obtained after rescreening. After automatically excised with the helper phage, positive clones were further identified by PCR. The size of Sj cDNA fragments in positive clones ranged from 300 bp to 1.8 kb. Six of these fragments were 300 bp, one was 1 kb, and five were 1.8 kb in size. The results indicate that the infected Mf serum could recognize Sj specific antigens. It is valuable to further study the immune protection of these cloned molecules.

[Expression and purification of recombinant Schistosoma japonicum paramyosin]

Paramyosin of Schistosoma japonicum was expressed at a high level in E. coli. The recombinant protein could be easily purified from bacteria lysate by fast protein liquid chromatography(FLPC) on a TALON resin column, due to the protein being expressed with a tag of six histidine residue fused to the N-terminus. The protein was completely soluble and could be eluted under non-denaturing condition using imidazole. To eliminate imidazole and residue of E. coli, the elution was further purified by ion-exchange chromatography. The purified protein will be used in water buffaloes in the study on protective immunity against Schistosoma japonicum.