Expression pattern of serum interleukin-7 in elderly septic patients and its prognostic value for predicting short-term mortality.

BACKGROUND: The identification of novel prognostic biomarkers in elderly septic patients are essential for the improvement of mortality in sepsis in the context of precision medicine. The purpose of this study was to explore the expression pattern and prognostic value of serum interleukin-7 (IL-7) in predicting 28-day mortality in elderly patients with sepsis. METHODS: Patients were retrospectively enrolled according to the sepsis-3.0 diagnostic criteria and divided into the survival group and non-survival group based on the clinical outcome at the 28-day interval. The baseline characteristic data, samples for the laboratory tests, and the SOFA, Acute Physiology and Chronic Health Evaluation (APACHE II), as well as Glasgow coma scale (GCS) scores, were recorded within 24 h after admission to the emergency department. Serum levels of IL-7 and TNF-α of the patients were quantified by the Luminex assay. Spearman correlation analysis, logistic regressive analysis and receiver operating characteristic curve (ROC) analysis were performed, respectively. RESULTS: Totally, 220 elderly patients with sepsis were enrolled, 151 of whom died in a 28-day period. Albumin (ALB), high-density lipoprotein (HDL), systolic pressure (SBP), and platelet (PLT) were found to be significantly higher in the survival group (p < 0.05). IL-7 was shown to be correlated with TNF-α in the non-survival group (p = 0.030) but not in the survival group (p = 0.194). No correlation was shown between IL-7 and other factors (p > 0.05). IL-7 and TNF-α were found to be independent risk factors associated with the 28-day mortality (OR = 1.215, 1.420). Combination of IL-7, SOFA and ALB can make an AUROC of 0.874 with the specificity of 90.77 %. Combination of IL-7 and TNF-α can make an AUROC of 0.901 with the sensitivity of 90.41 % while the combination of IL-7, TNF-α, and ALB can make an AUROC of 0.898 with the sensitivity of 94.52 %. CONCLUSIONS: This study highlights the importance of monitoring the serum level of IL-7 and TNF-α in elderly septic patients as well as evaluating the combinations with other routine risk factors which can be potentially used for the identification of elderly septic patients with higher risk of mortality.

Acute recurrent rhabdomyolysis in a Chinese boy associated with a novel compound heterozygous LPIN1 variant: a case report.

BACKGROUND: LPIN1-related acute recurrent rhabdomyolysis (RM), first reported in 2008, is an autosomal recessive inherited metabolic disease. In recent years, LPIN1 gene variants have been identified as one of the main causes of severe RM in children in Western countries. The disease is extremely rare in China, and we report a case of acute recurrent RM caused by a novel compound heterozygous LPIN1 variant. CASE PRESENTATION: A 15-year-old Chinese boy presented with myalgia after strenuous exercise, accompanied by transient increases in serum creatine kinase and myoglobin and persistent hyperuricaemia and hyperbilirubinaemia. Genetic analysis using high-throughput genomic sequencing and Sanger sequencing revealed that there was a compound heterozygous variant in the LPIN1 gene of the proband: the paternal c.2047A > G(p.I683V) was an unreported missense variant, and the maternal c.2107_2108 insAGG(p.Q703delin sQE) was an unreported in-frame variant. CONCLUSIONS: In children with RM, LPIN1 variants should always be considered in the differential diagnosis. The clinical features of our case are atypical, which highlights the importance of an accurate diagnosis by genetic testing. If detected early, the condition may be controlled, and the prognosis may be improved.

Prevalence of noroviruses in children hospitalized for acute gastroenteritis in Hohhot, China, 2012-2017.

BACKGROUND: Noroviruses (NVs) are an important cause of acute gastroenteritis (AGE) worldwide. There are limited data on the prevalence and molecular characterization of NVs in children in Hohhot, China. METHODS: Between January 2012 and December 2017, 1863 stool samples were collected at Maternal and Child Health Hospital in Hohhot. All samples were screened for NVs by real-time reverse transcription polymerase chain reaction (real-time RT-PCR). RESULTS: NVs were detected in 24.15% of these inpatient cases, ranging from 12.78 to 32.92% in different years. NV was detected throughout the year, with a peak in winter. Based on sequence analysis of the partial VP1 gene, the 306 identified NV strains were divided into six genotypes: GII.3 (71.24%), GII.4 (23.53%), and GII.2, GII.5, GII.6, and GII.13 (total 5.23%). Based on further sequence analysis of the RNA-dependent RNA polymerase (RdRp), GII.P12/GII.3, GII.Pe/GII.4, and GII.P4/GII.4 were identified as predominant genotypes, accounting for 92.6% of genotyped strains. The median age of the children with NV infection was 8.0 (range 0-59) months. However, children infected with GII.3 were younger (median 7.0 months) than GII.4-positive patients (median 10.0 months). CONCLUSION: NV contributed greatly to AGE among hospitalized children in Hohhot in China. Continuous surveillance is important for understanding the local prevalence and characterization of NV.

[Recognition and use of Aconitum carmichaeli from the pre-Qin period to Tang Dynasty-Also on rules in evolution of traditional Chinese medicine].

The recognition and use of Aconitum carmichaeli have undergone various changes from the pre-Qin period to Tang dynasty. From "the drug of evil" to "the leader of hundreds of medicine ", people's understanding of A. carmichaeli is more and more deep and specific. The medicinal values of A. Carmichaeli have been excavated, and it is widely used in brewing skill, agricultural production, Taoism, Buddhism and festival customs. Its function is becoming more and more diversified and routinized. By studying it, we can glimpse some rules in the evolution of traditional Chinese medicine, for instance relationships between drugs and poisons, drugs and non-drug; the inheritance and integration of medical books' recording; the generalization and routinization of Chinese medicinal medicines' functions, and so on.

Heterologous expression of methylketone synthase1 and methylketone synthase2 leads to production of methylketones and myristic acid in transgenic plants.

Some plants produce methylketones as potent defense compounds against various insects. Wild tomato (Solanum habrochaites), a relative of the cultivated tomato (Solanum lycopersicum), synthesizes large amounts of 2-methylketones in its glandular trichomes, but cultivated tomato trichomes contain little or no methylketones. Two enzymes, Solanum habrochaites methylketone synthase1 (ShMKS1) and ShMKS2, are required to convert ß-ketoacyl acyl-carrier protein intermediates of the fatty acid biosynthetic pathway to methylketones. ShMKS2 is a thioesterase that hydrolyzes ß-ketoacyl acyl-carrier protein, and ShMKS1 is a decarboxylase that converts the resulting 3-ketoacids to 2-methylketones. We introduced ShMKS2 by itself or together with ShMKS1 to Arabidopsis (Arabidopsis thaliana), tobacco (Nicotiana tabacum), and cultivated tomato under the control of the 35S, Rubisco small subunit, and tomato trichome-specific promoters. Young tobacco and Arabidopsis plants expressing both genes under the control of 35S and Rubisco small subunit promoters produced methylketones in their leaves but had serious growth defects. As plants matured, they ceased to produce methylketones. Tobacco plants but not Arabidopsis or tomato plants expressing only ShMKS2 under the 35S promoter also synthesized methylketones, but at a lower rate. Transgenic cultivated tomato plants expressing ShMKS1 and ShMKS2 under trichome-specific promoters had slightly elevated levels of methylketone. Trace amounts of myristic acid were also detected in transgenic plants constitutively expressing ShMKS2 with or without ShMKS1. These results suggest that increases in methylketone production in plants will require the targeting of the pathway to self-contained structures in the plant and may also require increasing the flux of fatty acid biosynthesis.

The tomato cis-prenyltransferase gene family.

cis-prenyltransferases (CPTs) are predicted to be involved in the synthesis of long-chain polyisoprenoids, all with five or more isoprene (C5) units. Recently, we identified a short-chain CPT, neryl diphosphate synthase (NDPS1), in tomato (Solanum lycopersicum). Here, we searched the tomato genome and identified and characterized its entire CPT gene family, which comprises seven members (SlCPT1-7, with NDPS1 designated as SlCPT1). Six of the SlCPT genes encode proteins with N-terminal targeting sequences, which, when fused to GFP, mediated GFP transport to the plastids of Arabidopsis protoplasts. The SlCPT3-GFP fusion protein was localized to the cytosol. Enzymatic characterization of recombinant SlCPT proteins demonstrated that SlCPT6 produces Z,Z-FPP, and SlCPT2 catalyzes the formation of nerylneryl diphosphate while SlCPT4, SlCPT5 and SlCPT7 synthesize longer-chain products (C25-C55). Although no in vitro activity was demonstrated for SlCPT3, its expression in the Saccharomyces cerevisiae dolichol biosynthesis mutant (rer2) complemented the temperature-sensitive growth defect. Transcripts of SlCPT2, SlCPT4, SlCPT5 and SlCPT7 are present at low levels in multiple tissues, SlCPT6 is exclusively expressed in red fruit and roots, and SlCPT1, SlCPT3 and SlCPT7 are highly expressed in trichomes. RNAi-mediated suppression of NDPS1 led to a large decrease in ß-phellandrene (which is produced from neryl diphosphate), with greater reductions achieved with the general 35S promoter compared to the trichome-specific MKS1 promoter. Phylogenetic analysis revealed CPT gene families in both eudicots and monocots, and showed that all the short-chain CPT genes from tomato (SlCPT1, SlCPT2 and SlCPT6) are closely linked to terpene synthase gene clusters.

Prevalence and predictors of metabolic abnormalities in Chinese women with PCOS: a cross- sectional study.

BACKGROUND: Polycystic ovary syndrome (PCOS) is a common condition estimated to affect 5.61% of Chinese women of reproductive age, but little is known about the prevalence and predictors in Chinese PCOS patients. This study aimed to determine the prevalence and predictors of the metabolic abnormalities in Chinese women with and without PCOS. METHODS: A large-scale national epidemiological investigation was conducted in reproductive age women (19 to 45 years) across China. 833 reproductive aged PCOS women, who participated in the healthcare screening, were recruited from ten provinces in China. Clinical history, ultrasonographic exam (ovarian follicle), hormonal and metabolic parameters were the main outcome measures. RESULTS: The prevalence of metabolic syndrome (MetS) as compared in PCOS and non-PCOS women from community were 18.2% vs 14.7%, and IR (insulin resistance) were 14.2% vs 9.3% (p < 0.001) respectively. After adjusting for age, the indicators (central obesity, hypertension, fasting insulin, SHBG, dyslipinaemia) for metabolic disturbances were significantly higher in PCOS than in non-PCOS groups. Using multivariate logistic regression, central obesity and FAI were risk factors, while SHBG was a protective factor on the occurrence of Mets and IR in PCOS women (OR: 1.132, 1.105 and 0.995). CONCLUSIONS: The risk factors of the metabolic syndrome and insulin resistance were BMI and FAI for PCOS women, respectively. The decrease of SHBG level was also a risk factor for insulin resistance in both PCOS and metabolic disturbance.

The effect of iron on growth, lipid accumulation, and gene expression profile of the freshwater microalga Chlorella sorokiniana.

The effects of iron on the growth, lipid accumulation, and gene expression profiles of the limnetic Chlorella sorokiniana CCTCC M209220 under photoautotrophy were investigated. The addition of iron up to 10(-5) mol l(-l) increased final cell densities by nearly 2-fold at 2.3 × 10(7) cells/ml, growth rate by 2-fold, and the length of the exponential phase by 5 days as compared to unsupplemented controls while 10(-3) mol l(-1) iron was toxic. The lipid content increased from 12 % for unsupplemented cultures to 33 % at 10(-4) mol l(-1) iron while the highest overall lipid yield reached 179 mg l(-1). A genefishing and qPCR comparison between the C. sorokiniana at low and high iron levels indicated increases in the expression of several genes, including carbonic anhydrase involved in microalgal cell growth, as well as acc1 and choline transporter related to lipid synthesis. This study provides insights into changes in gene expression and metabolism that accompany iron supplementation to Chlorella as well as potential metabolic engineering targets for improving growth and lipid synthesis in microalgae.

Application of the CRISPR/Cas9 Gene Editing Method for Modulating Antibody Fucosylation in CHO Cells.

Genetic engineering plays an essential role in the development of cell lines for biopharmaceutical manufacturing. Advanced gene editing tools can improve both the productivity of recombinant cell lines as well as the quality of therapeutic antibodies. Antibody glycosylation is a critical quality attribute for therapeutic biologics because the glycan patterns on the antibody fragment crystallizable (Fc) region can alter its clinical efficacy and safety as a therapeutic drug. As an example, recombinant antibodies derived from Chinese hamster ovary (CHO) cells are generally highly fucosylated; the absence of α1,6-fucose significantly enhances antibody-dependent cell-mediated cytotoxicity (ADCC) against cancer cells. This chapter describes a protocol applying clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated protein 9 (Cas9) approach with different formats to disrupt the α-1,6-fucosyltransferase (FUT8) gene and subsequently inhibit α-1,6 fucosylation on antibodies expressed in CHO cells.

Numerical study on the characteristics of roadway failure and instability in coal seam with rock parting.

In order to explore the mechanism of rockburst in coal seam with rock parting, a combination of on-site and numerical experiment is used to study the failure and instability process, crack propagation mechanism, and influencing factors. The following four points were addressed: (1) the instability is a process that roadway in coal seam with rock parting go through from stable locking in the initial stress unloading stage to slipping unlocking, and then to spatter ejection in slipping dynamic load disturbance stage. (2) The fracture development caused by unloading excavation of coal seam with rock parting will change from shear crack to tensile crack. In this process, coal-rock contact surface slip and coal-rock fracture are coupled with each other. (3) The greater the mining depth is, the greater the lateral pressure coefficient is, and the higher the rockburst risk is. On the contrary, the lower the risk of rockburst. (4) When choosing the support form of roadway in coal seam with rock parting, the two supporting forms of bolting (cable) and supplementary masonry support should be preferred. The results enrich the theory of the dynamics of surrounding rock fracture in coal mine, further clarify the potential dangers to mining-area roadways and working faces, and provide technical information to ensure the safe and efficient mining of bifurcated coal seam.

Genomic sequence analysis of a new reassortant infectious bursal disease virus from commercial broiler flocks in Central China.

We report the complete nucleotide sequence of a reassortant infectious bursal disease (IBD) virus (IBDV) HN isolate from commercial broiler flocks in central China. The genome consisted of 3,232 and 2,652 nucleotides in the coding regions of segments A and B, respectively. Alignment of both nucleotide and deduced amino acid sequences and phylogenetic analysis revealed that the genome segments A and B of HN were derived from the attenuated strain B87 and the VV strain OKYM. This is a new reassortant IBDV strain that has emerged in nature, involving segment A of a cell-culture-adapted attenuated vaccine strain B87.

Association of Perfusion Lesion Variables With Functional Outcome in Patients With Mild Stroke and Large Vessel Occlusion Managed Medically.

BACKGROUND AND OBJECTIVES: The best management of patients with mild stroke and large vessel occlusion (LVO) remains unclear. This study aimed to identify perfusion imaging predictors of poor functional outcome in such patients. METHODS: This cohort study retrospectively selected patients enrolled in the International Stroke Perfusion Imaging Registry between August 2011 and April 2022. The registry enrolled patients with acute ischemic stroke and with baseline CT perfusion scanned within 24 hours of stroke onset. This study identified patients with mild symptoms, defined by an NIH Stroke Scale score of ≤5. Patients with LVO of anterior circulation were selected. This study further selected patients who received medical management and excluded patients who received endovascular treatment. The primary outcome was poor functional outcome defined as a modified Rankin Scale of 3-6 at 3 months. Perfusion lesion was defined by delay time > 3 seconds on CTP. Regression analyses were used to identify clinical and imaging variables that predicted poor functional outcome. RESULTS: A total of 139 patients with mild stroke were included, of whom 27 (19%) had poor functional outcome. Patients with poor outcome, compared with those with good outcome, had much larger perfusion lesion volume (median 80 mL vs 41 mL, p < 0.001). Perfusion lesion was a significant predictor of poor outcome in either univariable regression (crude OR = 1.02, 95% CI = [1.01-1.03]) or multivariable regression model (adjusted OR = 1.01, 95% CI = [1.01-1.02]), adjusting for occlusion site, good collaterals, baseline stroke severity, age, IV thrombolysis (IVT), and onset to scan time. A perfusion lesion of 65 mL was the optimal cutpoint to identify poor functional outcome (sensitivity = 59%, specificity = 77%). Patients with perfusion lesion ≥65 mL, compared with patients with perfusion lesion <65 mL, showed a much higher rate of poor functional outcome (38% vs 11%, p < 0.001). Of the 139 patients in this study, 95 received IVT. Patients treated with or without IVT did not influence their outcomes (crude OR = 0.74, 95% CI = [0.31-1.78]). DISCUSSION: A perfusion lesion of ≥65 mL predicted poor functional outcome in mild stroke patients with LVO.

[Direct determination of hyperfine structures and isotope shifts in the 6s5d 3D --> 6p5d 3F transitions of Ba I].

In the present experiments, a new method of atomic spectral measurement using states optical pre-selection was proposed and demonstrated, and the measurement of hyperfine-structures and isotope shifts in the 6s5d 3D --> 6p5d 3F transitions of Ba I was taken as an example. A 791 nm laser was used to excite the different hyperfine transitions 6s6s 1S0 --> 6s6p 3P1 for different isotopes of barium and different hyperfine energy-levels of 6s5d 3D2 for these isotopes were populated by the 6s6p 3P1 --> 6s5d 3D2 spontaneous radiations, then the corresponding fluorescence spectra of 6s5d 3D2 --> 6p5d 3F2 transitions excited by another 778 nm laser were recorded. Comparing of these spectra, 22 lines were recognized and the hyperfine-structure constants of 6s5d 3D2 and 6p5d 3F2 of 135Ba and 137Ba were evaluated consequently while the isotope shifts of these transitions were also determined.

Enzymatic functions of wild tomato methylketone synthases 1 and 2.

The trichomes of the wild tomato species Solanum habrochaites subsp. glabratum synthesize and store high levels of methylketones, primarily 2-tridecanone and 2-undecanone, that protect the plants against various herbivorous insects. Previously, we identified cDNAs encoding two proteins necessary for methylketone biosynthesis, designated methylketone synthase 1 (ShMKS1) and ShMKS2. Here, we report the isolation of genomic sequences encoding ShMKS1 and ShMKS2 as well as the homologous genes from the cultivated tomato, Solanum lycopersicum. We show that a full-length transcript of ShMKS2 encodes a protein that is localized in the plastids. By expressing ShMKS1 and ShMKS2 in Escherichia coli and analyzing the products formed, as well as by performing in vitro assays with both ShMKS1and ShMKS2, we conclude that ShMKS2 acts as a thioesterase hydrolyzing 3-ketoacyl-acyl carrier proteins (plastid-localized intermediates of fatty acid biosynthesis) to release 3-ketoacids and that ShMKS1 subsequently catalyzes the decarboxylation of these liberated 3-ketoacids, forming the methylketone products. Genes encoding proteins with high similarity to ShMKS2, a member of the "hot-dog fold" protein family that is known to include other thioesterases in nonplant organisms, are present in plant species outside the genus Solanum. We show that a related enzyme from Arabidopsis (Arabidopsis thaliana) also produces 3-ketoacids when recombinantly expressed in E. coli. Thus, the thioesterase activity of proteins in this family appears to be ancient. In contrast, the 3-ketoacid decarboxylase activity of ShMKS1, which belongs to the alpha/beta-hydrolase fold superfamily, appears to have emerged more recently, possibly within the genus Solanum.

[Determination of 1, 1-dichloro-l-nitroethane in air of workplaces by gas chromatography].

OBJECTIVE: To establish a gas chromatography method for detecting the concentration of 1,1-dichloro-1-nitroethane in air of workplaces. METHOD: 1,1-dichloro-1-nitroethane in air of workplaces was collected by activated charcoal tube, absorbed using carbon disulfide and analyzed by Gas Chromatography (FID) with FFAP capillary column. RESULTS: The linear rang of 1,1-dichloro-1-nitroethane in this method was 4.0-858.2 microg/ml, the linear regression formula was Y = 283X-1076, the correlation coefficient was 0.9999, the lowest detection concentration was 0.4 mg/m3 (3L sampling air), the relative standard deviation (RSD) was 1.8%-4.1%, the desorption efficiency was 88.5%-90.6%, the breakthrough volume was > 0.7 mg, the sampling efficiency was 100%, the samples could be kept at ambient temperature for at least 7 days. CONCLUSION: The indicators of this method were conformed to the requirements of "Guide for establishing occupational health standards--Determination methods of air chemicals in workplace". This method could be used to detect 1,1-dichloro-1-nitroethane in air of workplaces.

Prevalence of post-traumatic stress disorder after earthquakes among the elderly in China: A meta-analysis.

BACKGROUND: The study aims to investigate the occurrence of post-traumatic stress disorder (PTSD) after earthquakes among the elderly. METHODS: Data from cross-sectional studies focusing on the prevalence of PTSD after earthquakes among the elderly were collected from PubMed, EMBASE, Cochrane Library, and China National Knowledge Infrastructure in December 2019. The search terms included post-traumatic stress disorder, earthquake, and elderly. This study used Review Manager 5.0 to evaluate the impact of the results. In addition, forest plots, sensitivity analysis, and bias analysis were carried out on the included articles. The combined estimate of the risk ratio and the standard deviation of the 95% confidence interval (95% CI) were measurements of the size of the effect. RESULTS: There were 4,834 patients included from 10 eligible studies. The sample sizes of PTSD group and non-PTSD group were 1,277 and 3,557, respectively. The meta-analysis showed that the overall occurrence of PTSD after earthquakes among the elderly was 0.25; the occurrence in females was higher than that in males, and the occurrence in the same province indicated little difference (Wenchuan city 0.25 and Ya'an city 0.24). CONCLUSIONS: After earthquakes, the occurrence of PTSD is higher among the elderly than among other age groups, and higher among the females than among the males, while there is little difference among different areas within the same province. This indicated that prioritized specific psychological interventions should be provided to the aged and the females.

Changed epidemiology of anthrax and molecular characteristics of Bacillus anthracis in Inner Mongolia Autonomous Region, China.

Anthrax is a natural foci disease in Inner Mongolia, which poses a severe threat to public health. In this study, the incidence number, rate and constituent ratio were used to describe the epidemiological characteristics of anthrax in the region from 1956-2018. The molecular correlation and genetic characteristics of the strains were investigated using canonical single nucleotide polymorphisms (CanSNP), multiple-locus variable-number tandem repeat analysis (MLVA-15) and whole genome sequencing (WGS). The epidemiological characteristics of anthrax in Inner Mongolia have altered significantly. The incidence of anthrax has decreased annually without vaccination, and the regional distribution of anthrax gradually transferred from central and western regions to the eastern. Moreover, the occupation distribution evolved from multiple early occupations to predominated by farmers and herdsmen. This change is closely related to policy factors and to changes in the means of production and the living habits of the local population. This indicates that reformulating the control and prevention strategies is essential. Both A. Br. Ames and A. Br. 001/002 subgroups were the predominant CanSNP genotypes of Bacillus anthracis in Inner Mongolia. A total of 36 strains constituted six shared MLVA-15 genotypes, suggesting an epidemiological link between the strains of each shared genotype. The six shared genotypes ([GT1, 9, 11 and 15] and [GT8 and 12]) consisting of 2-7 strains confirmed the occurrence of multiple point outbreaks and cross-regional transmission caused by multiple common sources of infection. Phylogenetic analysis based on the WGS core genome showed that strains from this study formed an independent clade (C.V.), and they were positioned close to each other, suggesting a common origin. Further comparison analysis should be performed to ascertain the geographic origin of these strains.

Multiple biochemical and morphological factors underlie the production of methylketones in tomato trichomes.

Genetic analysis of interspecific populations derived from crosses between the wild tomato species Solanum habrochaites f. sp. glabratum, which synthesizes and accumulates insecticidal methylketones (MK), mostly 2-undecanone and 2-tridecanone, in glandular trichomes, and cultivated tomato (Solanum lycopersicum), which does not, demonstrated that several genetic loci contribute to MK metabolism in the wild species. A strong correlation was found between the shape of the glandular trichomes and their MK content, and significant associations were seen between allelic states of three genes and the amount of MK produced by the plant. Two genes belong to the fatty acid biosynthetic pathway, and the third is the previously identified Methylketone Synthase1 (MKS1) that mediates conversion to MK of beta-ketoacyl intermediates. Comparative transcriptome analysis of the glandular trichomes of F2 progeny grouped into low- and high-MK-containing plants identified several additional genes whose transcripts were either more or less abundant in the high-MK bulk. In particular, a wild species-specific transcript for a gene that we named MKS2, encoding a protein with some similarity to a well-characterized bacterial thioesterase, was approximately 300-fold more highly expressed in F2 plants with high MK content than in those with low MK content. Genetic analysis in the segregating population showed that MKS2's significant contribution to MK accumulation is mediated by an epistatic relationship with MKS1. Furthermore, heterologous expression of MKS2 in Escherichia coli resulted in the production of methylketones in this host.

[Interaction among peroxisome proliferators-activated receptor alpha, cytochrome P450 oxysterol 7α-hydroxylase and estrogen receptor and its association with intrahepatic cholestasis in pregnant rats].

OBJECTIVE: To investigate the relationship between interaction of peroxisome proliferators-activated receptor alpha (PPARα), cytochrome P450 oxysterol 7α-hydroxylase (CYP7B1) and estrogen receptor (ER) and intrahepatic cholestasis in pregnant rats. METHODS: Eighty clean SD pregnant rats were selected and divided into four groups randomly with 20 in each. Since the 13th day of pregnancy, rats in the control group was injected subcutaneously with refined vegetable oil 2.0 ml×kg(-1)×d(-1), those in the low-dose, moderate-dose and high-dose groups received 17-α-ethynylestradiol (EE) 1.0 mg×kg(-1)×d(-1), 1.25 mg×kg(-1)×d(-1) and 1.5 mg×kg(-1)×d(-1), respectively. All rats were sacrificed at the 21(st) day of pregnancy and maternal hepatic tissues were collected. The serum levels of alanine aminotransferase (ALT), aspartate transaminase (AST), total bile acid (TBA) and bilirubin (BIL) were determined by enzyme linked immunosorbent assay (ELISA). The mRNA expressions of PPARα, CYP7B1, ERα and ERß in maternal rat livers were examined by real-time PCR. RESULTS: (1) Biochemical indicators: the serum levels of ALT, AST, TBA and BIL were significantly lower in the control group than in the rest 3 groups, respectively [control group: (41.1 ± 2.8) U/L, (44.4 ± 3.6) U/L, (26.4 ± 5.6) µmol/L and (2.8 ± 0.2) U/L; low-dose group: (48.2 ± 3.4) U/L, (47.9 ± 3.7) U/L, (36.4 ± 4.2) µmol/L and (4.2 ± 0.2) U/L; moderate-dose group: (70.4 ± 5.3) U/L, (68.4 ± 5.6) U/L, (64.3 ± 3.8) µmol/L and (6.2 ± 1.2) U/L; high-dose group: (72.4 ± 7.6) U/L, (70.2 ± 3.8) U/L, (72.4 ± 7.8) µmol/L and (8.2 ± 2.2) U/L, P < 0.05], and those in the moderate or high-dose groups were higher than in the low-dose group (P < 0.05). (2) mRNA expression of ERα and ERß: the mRNA expression of ERα in pregnant rat livers increased in a dose-dependent manner, which were all significantly higher than that in the control group, respectively (low-dose group: 0.76 ± 0.02); moderate-dose group: (0.99 ± 0.04; high-dose group: 1.21 ± 0.01; control group: 0.65 ± 0.01, P < 0.05), but no difference was found among the 4 groups in the mRNA expression of ERß (P > 0.05). (3) mRNA expression of CYP7B1 and PPARα: the mRNA expression of CYP7B1 in pregnant rat livers increased from the low-dose group to the high-dose group, and were all higher than that of the control group (low-dose group: 0.93 ± 0.01; moderate-dose group: 0.99 ± 0.06; high-dose group: 1.22 ± 0.04; control group: 0.75 ± 0.02, P < 0.05). However, the mRNA expression of PPARα decreased from the low-dose group to the high-dose group, and were all lower than that of the control group (low-dose group: 0.83 ± 0.05; moderate-dose group: 0.71 ± 0.02; high-dose group: 0.64 ± 0.03; control group: 1.35 ± 0.05; P < 0.05). CONCLUSIONS: The down regulated mRNA expression of PPARα, caused by higher dose of estrogen, may increase the expression of CYP7B1 due to the ineffectiveness of the inhibition of PPARα on CYP7B1, which may further stimulate the ERα activity and then induce intrahepatic cholestasis. Abnormal expression of PPARα, CYP7B1 and ER may play a role in the pathogenesis of estrogen-induced intrahepatic cholestasis.

[Investigation of the H2S contamination in cabin causing fishermen's eye burns].

OBJECTIVE: To investigate the H(2)S pollution in cabins which caused the fishermen's eye burns. METHODS: Fifty-six fishing boats' H(2)S concentration was surveyed and 56 fishermen's eyes were inspected. The air samples were collected from 21 fishing boats' cabins, where the eye burns took place and the monitoring conditions met the inspection requirement, in order to confirm the concentration of H(2)S when eye burns and the systemic poisoning happened. Thirty fishing boats were divided into two groups: one was using air ventilating and spraying, the other was using naturally ventilation to find out the effective method of dispersing H(2)S. Five fishing boats were surveyed in which the fishermen had slight symptom of bulbar conjunctiva hyperemia and cough to find out the minimum concentration of H(2)S which caused the eye burns and respiratory mucosa. RESULTS: Among 56 fishermen who were surveyed, 46 fishermen's eyes (92 eyes) burnt and they were from 21 vessels, 10 of them (20 eyes) were moderate, 36 of them (72 eyes) were light. The concentration of H(2)S in the 21 fishing boats' cabins which caused eye burns was (99 ± 38) mg/m(3). The first measuring of the concentration of H(2)S in the 30 fishing boats in which fish were not discharged yet was (219 ± 31) mg/m(3). Air ventilating and spraying group's concentration of H(2)S was (213 ± 24) mg/m(3), while that of naturally ventilation group's was (225 ± 36) mg/m(3). Dispersing after 1 hour, the concentration of H(2)S of air ventilating and spraying group was (21 ± 3) mg/m(3), the decreased concentration was (192 ± 21) mg/m(3), fell 90%; the concentration of naturally ventilation group was (184 ± 36) mg/m(3), the decreased concentration was (41 ± 8) mg/m(3), fell 18%. The difference between the two groups' decreased concentration was significant (t = 25.627, P < 0.05). The threshold value of H(2)S concentration that could cause the eye burns was 38 mg/m(3)(exposure time 120 min). In 7 vessels, the concentration of H(2)S in the cabins was (123 ± 9) mg/m(3) where 10 fishermen's moderate eye burns happened. In other 7 vessels, the concentration of H(2)S in the cabins was (54 ± 7) mg/m(3) where 19 fishermen's light eye burns happened. The difference of H(2)S concentration between the two groups was significant (t = 14.236, P < 0.05). CONCLUSION: High H(2)S concentration and long exposure time in cabin can cause serious eye burns. The bilge air ventilation and inner cabin spraying are the effective method to clear the H(2)S in cabin within short time.