139对双生子红细胞钠、钾离子的遗传度分析

利用遗传流行病学方法调查了天津市南开区139对双胞胎,其中单卵双生(MZ)74对,双卵双生(DZ)65对。并用几种不同的遗传度估计方法分析了红细胞Na⁺、K⁺的共同基因和共同环境因素对血压的影响。结果表明遗传因素、共同环境因素及双胞胎各自的环境因素对血压影响近似的是RBC Na⁺,h²=0.32,C²=0.35,u²=0.33。环境因素为主要原因的是RBC K⁺,C²=0.97。     

Sperm Na+, K+-ATPase α4 and plasma membrane Ca2+-ATPase (PMCA) 4 regulation in asthenozoospermia

Asthenozoospermia, which is characterized by reduced motility, is one of the etiologies of male infertility. Its biochemical and functional consequences include altered ATPase activity. This study investigated the activities of Na⁺, K⁺-ATPase and Ca²⁺-ATPase and the expression of Na⁺, K⁺-ATPase α4 and PMCA4 isoforms in human sperm of asthenozoospermic infertile men. Nineteen samples from asthenozoospermic infertile couples were examined in this study. Computerized-assisted semen analysis (CASA) was performed, and the enzyme activity was measured based on the ability of ATPase to release organic phosphate from ATP as a substrate. The Na⁺, K⁺-ATPase α4 and PMCA4 isoform expression levels were measured by western immunoblotting, whereas the protein distribution was examined by immunocytochemistry. This showed that the Na⁺, K⁺-ATPase activity and the Na⁺, K⁺-ATPase α4 isoform expression were lower in the asthenozoospermia group than in the normozoospermia group (8.688±1.161 versus 13.851±1.884 µmol Pi/mg protein/h, respectively; p>0.05). In contrast, the Ca²⁺-ATPase activity was significantly higher in the asthenozoospermia group than in the normozoospermia group (11.154±1.186 versus 2.725±0.545 µmol Pi/mg protein/h, respectively; p<0.05). In comparison, PMCA4 expression in the asthenozoospermia group was lower than in the normozoospermia group (p>0.05). The altered ATPase activity and isoform expression in asthenozoospermia may impair sperm structure and function.     

CD4+CD25+ regulatory T cell-mediated changes in the expression of endocytic receptors and endocytosis process of human dendritic cells

CD4⁺CD25⁺ regulatory T cells (Tregs) are known to inhibit immune responses to antigens. Since, the process of antigen uptake by dendritic cells (DC) is central to induction of immune responses, we analyzed the effect of Tregs on the expression of endocytic receptors on DC and its repercussion on antigen uptake. Our results demonstrate that Tregs down-regulate the expression and uptake of antigens via C-type lectin-like receptors CD206 and DC-SIGN, restrain the pinocytosis process of DC and augment the expression of FcγRIIB, an inhibitory Fcγ receptor the engagement of which by IgG-bound antigens leads to inhibition of DC activation. Our results thus provide an additional insight on the pertinence of strategies aimed at blocking Treg functions towards improved vaccination protocols.     

Alcohol-induced suppression of gluconeogenesis is greater in ethanol fed female rat hepatocytes than males.

The impact of alcohol-induced suppression on hepatic gluconeogenesis (HGN) after chronic ethanol consumption between males and females is unknown. To determine the effects of chronic alcohol consumption (8 weeks) on HGN, the isolated hepatocyte technique was used on 24 h fasted male and female Wistar rats. Livers were initially perfused with collagenase and the hepatocytes were isolated. Aliquots of the cell suspension were placed in Krebs-Henseleit buffer and incubated for 30 min with lactate, [U -14C]lactate, and nine different concentrations of ethanol (EtOH). Dose-effect curves were generated for the determination of maximal and half-maximal alcohol-induced inhibition on HGN. There was no significant difference in HGN (lactate only and no EtOH) between males and females fed the control diet (88.5 +/- 5.1 nmol/mg protein/30 min). Similarly, the HGN (lactate only and no EtOH) in males fed the ethanol diet (ME) were not significantly different (82.8 +/- 3.5 nmol/mg protein/30 min) compared to controls. In contrast, the females chronically fed the ethanol diet (FE) had significantly (P < .05) lower HGN (67.8 +/- 4.6 nmol/mg protein/30 min) compared to both ME and controls. With alcohol in the incubation medium, the HGN significantly (P<.05) declined in all groups. While alcohol suppressed HGN to a larger (P < .05) extent in ME (45.8 +/- 3.7 nmol/mg protein/30 min) compared to controls (64.0 +/- 3.8 nmol/mg protein/30 min), the inhibition was even greater (P < .05) in FE (32.7 +/- 3.2 nmol/mg protein/30 min). The more pronounced effect of chronic alcohol consumption on HGN in the presence of ethanol in female hepatocytes was supported by the concomitant decreases (P < .05) in 14C-lactate incorporation into 14C-glucose, lactate uptake, and 14C-lactate uptake. The results suggest that chronic alcohol consumption elicits a greater reduction on HGN in the presence of ethanol in the hepatocytes of females compared to males.     

Chromium Tolerance and Reduction Potential of a <Emphasis Type="Italic">Bacillus</Emphasis> sp.ev3 Isolated from Metal Contaminated Wastewater

This study was aimed at assessing the ability of Bacillus sp.ev3 to reduce hexavalent chromium into its trivalent form. Bacillus sp.ev3 could tolerate Cr(6+) (4800 microg/mL), Pb(2+) (800 microg/mL), Cu(2+) (200 microg/mL), Cd(2+) (50 microg/mL), Zn(2+) (400 microg/mL), Ni(2+) (4000 microg/mL) and Hg(2+) (50 microg/mL). Bacillus sp.ev3 showed optimum growth at 37 degrees C and pH at 7. Bacillus sp.ev3 could reduce 91% of chromium from the medium after 96 h and was also capable to reduce 84% chromium from the industrial effluents after 144 h. Cell free extracts of Bacillus sp.ev3 grown in the presence of Cr showed reduction of 70%, 45.6% and 27.4% at concentrations of 10 microg Cr(6+)/mL, 50 microg Cr(6+)/mL and 100 microg Cr(6+)/mL, respectively.     

Subcellular distribution of Cd and Pb in earthworm Eisenia fetida as affected by Ca2+ ions and Cd-Pb interaction

A semi-static solution culture method was used to study the effects of Ca²⁺ supply and interaction of Cd–Pb on the subcellular distribution of Cd and Pb in earthworm Eisenia fetida. The subcellular distribution of Cd and Pb was shown to be metal specific. About 80% of the Cd was distributed in the cytosol (fraction G), and only about 20% of total Cd was found in the tissue and cell membrane (fraction E) and the microsomes (fraction F). Nearly 50% of the Pb was rich in the tissue and cell membrane (fraction E). The supply of Ca²⁺ ions significantly decreased Cd concentration in the cytosol (fraction G) and the whole tissue of the E. fetida. At the subcellular level, the addition of Pb²⁺ ions significantly decreased the Cd percentage associated with fraction G from 83.7% to 58.4% and increased fraction E from 10.7% to 34.0%, respectively.     

Modulation of HIV peptide antigen specific cellular immune response by synthetic α- and β-defensin peptides

Defensin peptides have their direct role in host defense against microbial infection as innate molecules and also thought to contribute to adaptive immunity by recruiting naïve T-cells and immature dendritic cells at the site of infection through CCR6 receptor. The main aim of the present study is to investigate the efficacy of defensins for the induction of cell mediated immune response against the peptide antigen of HIV-1 encapsulated in PLG microparticles through intranasal (IN) route in mice model. To characterized, we have analyzed T-cell proliferation, Th1/Th2 cytokines, β-chemokines production and IFN-γ/perforin secretion from CD4⁺/CD8⁺ T-cells in response to HIV immunogen alone and with defensins at different mucosal site i.e. lamina propria (LP), spleen (SP) and peyer's patches (PP). The cellular immunogenicity of HIV peptide with defensin formulations showed a significantly higher (p < 0.001) proliferation response as compared to individual HIV peptide. The enhanced cytokines measurement profile showed mixed Th1 and Th2 type of peptide specific immune response by the incorporation of defensins. In the continuation, enhancement in MIP-1α and RANTES level was also observed in HIV peptide–defensin formulations. The FACS data had revealed that CD4⁺/CD8⁺ T-cells showed significantly (p < 0.001) higher IFN-γ and perforin secretion in HIV with defensin peptide formulations than HIV antigen alone group. Thus, the study emphasized here that defensin peptides have a potential role as mucosal adjuvant, might be responsible for the induction of cell mediated immunity when administered in mice through IN route with HIV peptide antigen.     

HBsAg阳性母亲HBeAg和新生儿调节性T淋巴细胞关系及对HBV宫内传播的影响

目的 探讨HBsAg阳性母亲的HBeAg与新生儿CD₄⁺CD₂₅⁺Foxp3⁺调节性T淋巴细胞（Treg）含量的关系以及对增加新生儿HBV宫内传播发生风险的影响。方法 选择太原市第三人民医院妇产科分娩的270对HBsAg阳性母亲及其新生儿,收集一般人口学特征及分娩情况等资料,采用荧光定量聚合酶链式反应（FQ-PCR）和化学发光免疫试验（CLIA）检测母婴外周血HBV DNA及HBV血清学标志物;流式细胞术（FCM）检测新生儿外周血Treg等免疫细胞含量。结果 母亲HBeAg阳性是HBV宫内传播的危险因素（OR=4.08,95% CI：1.89~8.82）;母亲HBeAg阳性者新生儿Treg含量高于阴性者（Z=2.29,P=0.022）;按母亲HBeAg滴度分为5组,各组间新生儿Treg、HBeAg及母亲HBV DNA随母亲HBeAg滴度增高呈上升趋势,差异均有统计学意义（χ²=18.73,P<0.001;χ²=181.60,P<0.001;χ²=183.09,P<0.001）。偏相关分析中控制母亲HBV DNA以及新生儿HBeAg后,母亲HBeAg与新生儿Treg呈正相关（r_s=0.19,P=0.039）。新生儿Treg与浆细胞样树突状细胞（pDC）、CD₄⁺T淋巴细胞含量为负相关（r_s=-0.21,P=0.017;r_s=-0.23,P=0.009）。结论 HBsAg阳性母亲的HBeAg可能通过上调新生儿Treg含量,影响树突状细胞和效应T淋巴细胞的功能及其对HBV的免疫应答,从而增加新生儿发生HBV宫内传播的风险。     

Synthesis and Na+/H+ exchanger inhibitory activity of benzoylguanidine derivatives

Twenty-two compounds of substituted benzoylguanidine derivatives were designed and synthesized as potent NHE1 inhibitors. Twelve compounds showed more potent NHE1 inhibitory activity than cariporide. The activities of compounds 7e, 7h and 7j (IC₅₀ = 0.073 ± 0.021, 0.084 ± 0.012 and 0.068 ± 0.021 nmol/L, respectively) were two orders of magnitude higher than that of cariporide (30.7 ± 2.5 nmol/L). Myocardial cells in vitro screening showed 7j had highlighted protective effect on cardiomyocytes subjected to hypoxia/reoxygenation. Thus it is valuable for further investigation.     

Algo Used by Homecare Nonoccupational Therapists Selecting Bathing Assistive Technology: Enhancing Standardization by Exploring Clinical Reasoning

Algo is a clinical decision algorithm developed to support nonoccupational therapists in establishing assistive technology recommendations to enable physically disabled adults to perform their hygiene at home. This study aimed to explore the in-depth clinical reasoning of nonoccupational therapists using Algo to pinpoint the items leading to disagreements regarding recommendations. A multiple-case study was conducted with eight nonoccupational therapists trained to use Algo and filmed while using it with six standardized clients. Explicitation interviews were conducted for the conflicting recommendations. Identifying the key reasoning skills to develop in Algo users has led to three recommendations to enhance standardization with seniors.     

MF59-adjuvanted influenza vaccine (FLUAD) in children: Safety and immunogenicity following a second year seasonal vaccination

After priming with two intramuscular doses of MF59^®-adjuvanted (Sub/MF59) or split influenza vaccines during the 2006/07 season, 89 healthy children received a third booster dose of the respective vaccine (2007/08 Northern Hemisphere formulation) approximately 1 year later, and were followed up for 6 months post-third injection. Immunogenicity was evaluated on 81 of them by a hemagglutination inhibition (HI) assay before and 3 weeks after vaccination.     

Dosimetry of inhaled 219Rn progeny

During prostate cancer treatment with ²²³Ra. ²¹⁹Rn (actinon) occurs and may be exhaled by the patient. Nurses and other hospital employees may inhale this radionuclide and its decay products. The alpha-emitting decay products of actinon deposited within a body will irradiate tissues and organs. Therefore. it is necessary to evaluate organ doses of actinon progeny. The purpose of this study is to set up a dosimetric method to assess dose coefficients for actinon progeny. The effective dose coefficients were calculated separately for three modes. The unattached mode which concerned the activity median thermodynamic diameter (AMTD) of 1 nm. and the nucleation and accumulation modes which are represented by activity median aerodynamic diameters (AMAD) of 60 and 500 nm respectively. The recent biokinetic models of actinon progeny developed in the Occupational Intakes of Radionuclides (OIR) publications series of the International Commission of Radiological Protection (ICRP) were implemented on BIOKMOD (Biokinetic Modeling) to calculate the number of nuclear transformations per activity intake of actinon progeny. The organ equivalent and effective dose coefficients were determined using the dosimetric approach of the ICRP. The inhalation dose coefficients of actinon progeny are dominated by the contribution of lung dose. The calculated dose coefficients of ²¹¹Pb and ²¹¹Bi are 5.78 × 10⁻⁸ and 4.84 × 10⁻⁹ Sv.Bq⁻¹ for unattached particles (AMTD = 1 nm). and 1.4 × 10⁻⁸ and 3.55 × 10⁻⁹ Sv.Bq⁻¹ for attached particles (AMAD = 60 nm). and 7.37 × 10⁻⁹ and 1.91 × 10⁻⁹ Sv.Bq⁻¹ for attached particles (AMAD = 500 nm). These values are much closer to those of the recently published ICRP 137.     

Dose-Response Effect of Arabinoxylooligosaccharides on Gastrointestinal Motility and on Colonic Bacterial Metabolism in Healthy Volunteers

Objective: Arabinoxylooligosaccharides (AXOS) are non-digestible in the upper gastrointestinal tract and have been shown to exert prebiotic effects in animals. The aim of this study was to characterize the influence of AXOS with an average degree of polymerization of 15 and an average degree of arabinose substitution of 0.26 (AXOS-15-0.26) on gastrointestinal motility and colonic bacterial metabolism in healthy human volunteers.

Methods: Twelve healthy volunteers received five test meals, containing different amounts of AXOS-15-0.26, with one week intervals between each test meal. Breath tests were used to measure gastric emptying rate, oro-cecal transit time (OCTT) and hydrogen excretion. Colonic bacterial metabolism was estimated using the biomarkers lactose-[¹⁵N, ¹⁵N′]-ureide (¹⁵N-LU) and p-cresol.

Results: Gastric emptying and OCTT were not influenced by addition of varying amounts of AXOS-15-0.26. Administration of 2.2g or 4.9g AXOS-15-0.26 significantly decreased the urinary ¹⁵N-excretion (respectively p = 0.008 and p = 0.035) as compared to the baseline, whereas fecal ¹⁵N-excretion was significantly increased (respectively p = 0.034 and p = 0.019). This shift from urinary to fecal ¹⁵N-excretion suggests a higher uptake or incorporation by bacteria due to the stimulation of colonic bacterial growth and/or metabolic activity. Furthermore, a significant increase in hydrogen excretion after administration of 2.2g (p = 0.002) and 4.9g (p = 0.004) AXOS-15-0.26 was observed. No influence on urinary p-cresol excretion was observed.

Conclusion: These findings suggest that a minimal dose of 2.2g AXOS-15-0.26 favorably modulates the colonic bacterial metabolism in healthy humans. However, long term studies are required to confirm a possible prebiotic effect.     

Immunogenicity assay validation for an HIV vaccine trial: high IFNγ+/IL-2+ CD8+ T cells background in healthy Thais

In a vaccine trial, assays for vaccine immunogenicity if performed locally will strengthen local site, can save costs and avoid hurdles associated with specimen transport. Here we report the optimization and validation of an Intracellular Cytokine Staining (ICS) assay which was undertaken in preparation for a phase I HIV vaccine trial conducted in Thailand. Intra-, and inter-operator variability were easily established. However, while attempting to set population cut offs for a positive response we found 4/36 (11%) high background responses of IFNγ⁺ and/or IL-2⁺ CD8⁺ T cells (>1%) in normal healthy volunteers. The determinates of these unexpected responses were explored and minimized.     

Effects of Magnesium on Cardiac Excitation-Contraction Coupling

Objective: Magnesium regulates a large number of cellular processes. Small changes in intracellular free Mg²⁺ ([Mg²⁺]_i) may have important effects on cardiac excitability and contractility. We investigated the effects of [Mg²⁺]_i on cardiac excitation-contraction coupling.

Methods: We used our ionic-metabolic model that incorporates equations for Ca²⁺ and Mg²⁺ buffering and transport by ATP and ADP and equations for MgATP regulation of ion transporters (Na⁺-K⁺ pump, sarcolemmal and sarcoplasmic Ca²⁺ pumps).

Results: Model results indicate that variations in cytosolic Mg²⁺ level might sensitively affect diastolic and systolic Ca²⁺, sarcoplasmic Ca²⁺ content, Ca²⁺ influx through L-type channels, efficiency of the Na⁺/Ca²⁺ exchanger and action potential shape. The analysis suggests that the most important reason for the observed effects is a modified normal function of sarcoplasmic Ca²⁺-ATPase pump by altered diastolic MgATP levels.

Conclusion: The model is able to reproduce qualitatively a sequence of events that correspond well with experimental observations during cardiac excitation-contraction coupling in mammalian ventricular myocytes.     

Preliminary assessment of ecological exposure of adult residents in Fukushima Prefecture to radioactive cesium through ingestion and inhalation

Objective

This study aims to estimate the ecological exposure of adult residents of Fukushima Prefecture to ¹³⁴cesium (Cs) and ¹³⁷Cs through ingestion and inhalation between July 2 and July 8, 2011.

Methods

Fifty-five sets of meals with tap water, each representing one person’s daily intake, were purchased in local towns in Fukushima Prefecture. Locally produced cow’s milk (21 samples) and vegetables (43 samples) were also purchased. In parallel, air sampling was conducted at 12 different sites using a high-volume sampler. Nineteen sets of control meals were collected in Kyoto in July 2011. ¹³⁴Cs and ¹³⁷Cs levels in the samples were measured using a germanium detector.

Results

Radioactivity was detected in 36 of the 55 sample meals from Fukushima, compared with one of 19 controls from Kyoto. The median estimated dose level (μSv/year) was 3.0, ranging from not detectable to 83.1. None of the cow’s milk (21) or vegetable (49) samples showed levels of contamination above the current recommended limits (Bq/kg) of 200 for milk and 500 for vegetables. The total effective dose levels by inhalation were estimated to be <3 μSv/year at nine locations, but samples at three other locations close to the edge of the 20-km radius from the crippled nuclear power plant showed higher levels of contamination (μSv/year): 14.7 at Iitate, 76.9 at Namie, and 27.7 at Katsurao.

Conclusions

Levels of exposure to ¹³⁴Cs and ¹³⁷Cs in Fukushima by ingestion and inhalation are discernible, but generally within recommended limits.

Electronic supplementary material

The online version of this article (doi:10.1007/s12199-011-0251-9) contains supplementary material, which is available to authorized users.     

Low-molecular-weight-chitosan ameliorates cadmium-induced toxicity in the freshwater crab, Sinopotamon yangtsekiense

Cadmium (Cd) has been shown to induce oxidative stress. Low-molecular-weight-chitosan (LMWC) has been demonstrated to exhibit potent antioxidant effects. We investigated the regulation role in Cd²⁺-induced oxidative damage in the hepatopancreas of the freshwater crab Sinopotamon yangtsekiense and the protective effect of LMWC. The results showed that Cd²⁺ significantly increased the hepatopancreatic metallothionein (MT) mRNA levels and protein kinase C (PKC) activity while decreasing the activities of Na⁺,K⁺-ATPase and Ca²⁺-ATPase in crabs relative to the control group. Co-treatment with LMWC suppressed the levels of MT and PKC but raised the activities of Na⁺,K+-ATPase and Ca²⁺-ATPase in hepatopancreatic tissues compared with the crabs exposed to Cd²⁺ alone. We postulate that LMWC may exert its protective effect through regulating the expressions of MT, PKC, Na⁺,K⁺-ATPase and Ca²⁺-ATPase, thereby enhancing antioxidant defense. These observations suggest that LMWC may be beneficial because of its ability to alleviate the Cd²⁺-induced damages to the crabs.     

Seasonal Variation in TP53 R249S-Mutated Serum DNA with Aflatoxin Exposure and Hepatitis B Virus Infection

Background: Chronic hepatitis B virus (HBV) infection and dietary aflatoxin B₁ (AFB₁) exposure are etiological factors for hepatocellular carcinoma (HCC) in countries with hot, humid climates. HCC often harbors a TP53 (tumor protein p53) mutation at codon 249 (R249S). In chronic carriers, 1762^T/1764^A mutations in the HBV X gene are associated with increased HCC risk. Both mutations have been detected in circulating cell-free DNA (CFDNA) from asymptomatic HBV carriers.Objective: We evaluated seasonal variation in R249S and HBV in relation to AFB₁ exposure.Methods: R249S was quantitated by mass spectrometry in CFDNA in a cross-sectional survey of 473 asymptomatic subjects (237 HBV carriers and 236 noncarriers) recruited in three villages in the Gambia over a 10-month period. 1762^T/1764^A HBV mutations were detected by quantitative polymerase chain reaction. In addition, the HBV S gene was sequenced in 99 subjects positive for HBV surface antigen (HBsAg).Results: We observed a seasonal variation of serum R249S levels. Positivity for R249S and average concentration were significantly higher in HBsAg-positive subjects surveyed during April–July (61%; 5,690 ± 11,300 R249S copies/mL serum) than in those surveyed October–March [32% and 480 ± 1,030 copies/mL serum (odds ratio = 3.59; 95% confidence interval: 2.05, 6.30; p < 0.001)]. Positivity for HBV e antigen (HBeAg) (a marker of HBV replication) and viral DNA load also varied seasonally, with 15–30% of subjects surveyed between April and June HBeAg positive, compared with < 10% surveyed during other months. We detected 1762^T/1764^A mutations in 8% of carriers, half of whom were positive for R249S. We found HBV genotype E in 95 of 99 HBsAg-positive subjects.Conclusion: R249S is detectable in CFDNA of asymptomatic subjects. Evidence of temporal and quantitative variations suggests an interaction among AFB₁ exposure, HBV positivity, and replication on TP53 mutation formation or persistence.     

Mercury concentrations are low in commercial fish species of Lake Ziway, Ethiopia, but stable isotope data indicated biomagnification

Stable isotope ratios of nitrogen (δ¹⁵N) and carbon (δ¹³C), complemented by stomach content data, were used to assess the food web structure and trophic transfer of mercury (Hg) in four commercial fish species of Lake Ziway, Ethiopia: Nile tilapia (Oreochromis niloticus), catfish (Clarias gariepinus), Tilapia zillii, and golden carp (Carassius auratus). Total mercury (THg in mg kg⁻¹, ww) concentrations were low, with mean values of 0.033, 0.034, 0.025, and 0.011, in C. gariepinus, T. zillii, C. auratus, and O. niloticus, respectively. The relationships between mercury concentrations against total length (TL) and total weight (TW) were positive and significant in T. zillii, C. auratus, and C. gariepinus (P<0.01), but not in O. niloticus, which even showed a decreasing tendency with increase in TL and TW. Regression of log THg vs. δ¹⁵N among all fish species showed a significant correlation, indicating that mercury is biomagnifying along the food web of Lake Ziway. Isotope ratios indicated that C. gariepinus occupied the highest trophic level of the food web of Lake Ziway; but contained similar THg concentrations as T. zillii, which is located at a lower trophic level, probably due to a faster growth rate of C. gariepinus, and thus an example of biodilution.