[The effects of exposure to ozone on sperm quality in Wuhan]

Objective: To evaluate the effects of exposure to ozone (O(3)) on sperm quality during different stages of spermatogenesis. Methods: All 1 780 subjects attending to the Reproductive Medicine Center in Renmin Hospital of Wuhan University were recruited from April, 4, 2013 to June, 30, 2015. The subjects were living in Wuhan more than 3 months before attending to the program, aged 20 to 40 years. Semen quality (sperm concentration and sperm count) were measured according to standardized protocols. Corresponding daily 8 hours average concentration of O(3), other polluted concentration, average temperature and relative humidity were collected in different time, including lag 0, 10, 70 and 90 d, and lag 0-9 d, lag 10-14 d, lag 70-90 d and lag 0-90 d. After controlling the age, BMI, education level and other confounders, generalized linear Model was used to investigate the association between O(3) and sperm quality during different stages of spermatogenesis. Results: Average daily concentration of O(3) during the study period was (114.20±74.88) μg/m(3) and the mean values of sperm concentration and count were (76.32±50.17) millions/ml and (164.77 ± 133.05) millions/sample, respectively. Exposure to O(3) was associated with decreasing sperm concentration and count. For every 1 μg/m(3) increase of O(3), the decrease of sperm concentration during lag 10, lag 0-9 and lag 10-14 days exposure windows were 0.040 (95%CI: 0.004-0.077) millions/ml, 0.081 (95% CI: 0.003-0.158) millions/ml and 0.059 (95% CI: 0.001-0.116) millions/ml, respectively. And the decrease of sperm count during lag 10, lag 0-9 days exposure windows were 0.105 (95%CI: 0.008-0.202) millions/sample and 0.221 (95% CI: 0.016-0.426) millions/sample. After stratification, in the ozone concentration <P(50) and ≥P(50) groups, and the number of subjects in each exposure windows (lag 0-9, lag 10-14, lag 70-90, lag 0-90 days) were 887 and 893, 890 and 890, 895 and 885, 889 and 891, respectively. Compared with the high ozone concentration group, the effects of low group were more obvious. Furthermore, the effects of low concentration group was the most obvious during lag 10-14 days, for every 1 μg/m(3) increase of O(3), the decrease of sperm concentration was 0.249 (95% CI: 0.028-0.470) millions/ml. After sensitivity analysis, the effects of exposure to ozone on sperm concentration and sperm count remained relatively unchanged. Conclusion: Our study suggested that exposure to O(3) was significantly associated with decreasing semen quality in Wuhan. Moreover, the effects were more obvious during lag 0-9 and lag 10-14 days.

[Impact of atmospheric particulate matter at different period of gestation on low birth weight: a meta-analysis]

Objective: To analyze the influence of atmospheric particulate matters (PM(2.5) and PM(10)) on low-birth-weight (LBW) infants at different periods of gestation. Methods: We conducted a systematic literature search for 2 471 articles related to particulate matter and LBW published from January 1st 2000 to January 1st 2016 using the PubMed, Cochrane Library, Web of Science, Science Direct, Chinese Web of Knowledge, Wanfang and Weipu, and the keywords were" air pollution" , "adverse birth outcomes" , "adverse pregnancy outcomes" , "low birth weight/LBW" . According to criteria, 27 literatures were selected and included. Metafor package of the R 3.1.1 Software was used to check the heterogeneity and merge the effect value of the selected literatures, and sensitivity analysis and publication bias were detected and adjusted. Results: A total of 2 471 studies selected form the databases, 27 enrolled in this analysis according to the inclusion and exclusion criteria. Each 10 μg/m(3) increase in PM(2.5) was associated with combined OR values of 1st trimester, 2nd trimester, 3rd trimester and entire gestation at 1.02(95% CI: 0.87-1.19), 1.03 (95% CI: 0.91-1.16) , 1.07 (95%CI: 1.04-1.11) and 1.09 (95%CI: 1.04-1.15), respectively. And 10 μg/m(3) increase in PM(10) was associated with combined OR values of 1st trimester, 2nd trimester, 3rd trimester and entire gestation at 1.66 (95%CI: 1.06-2.61), 1.58 (95%CI:1.28-1.95) , 1.38 (95%CI: 1.23-1.56) and 1.04 (95%CI: 0.99-1.09), respectively. After adjusting the bias of publication, each 10 μg/m(3) increase in PM(2.5) was associated with the risk of low birth weight at 1.11 (95%CI: 1.02-1.21). Conclusion: This meta analysis supports an adverse impact of maternal exposure to particulate air pollution on low birth weight, varying in effects by exposure period.

Reciprocal regulation between mRNA and microRNA enables a bistable switch that directs cell fate decisions

Micro RNAs (miRNAs) serve as crucial post-transcriptional regulators in a variety of essential cell fate decisions. However, the contribution of mRNA-miRNA mutual regulation to bistability is not fully understood. In the present study, we built a set of mathematical models of mRNA-miRNA interactions and systematically analyzed the sensitivity of the response curves under various conditions. Our findings indicate that mRNA-miRNA reciprocal regulation could manifest ultrasensitivity to subserve the generation of bistability when equipped with a positive feedback loop. We also find that the region of bistability is expanded by a stronger competing endogenous mRNA. Interestingly, bistability can be generated without a feedback loop if multiple miRNA binding sites exist on a target mRNA. Thus, we demonstrate the importance of simple mRNA-miRNA reciprocal regulation in cell fate decisions.

[Acute impact of cold spells on mortality during 2001-2011 in Jiang'an district of Wuhan, China]

OBJECTIVE

To evaluate the association between cold spells and nonaccidental mortality from 2001 to 2011 in the Jiang'an District of Wuhan, China.

METHODS

We collected mortality data for December 2001 to 2010 and January to March 2002 to 2011 in the study area. According to the International Classification of Diseases, we stratified the mortality data into three cause-specific categories: nonaccidental mortality, cardiovascular mortality, and respiratory mortality. We also obtained meteorological data (from the China Meteorological Administration) and ambient pollution data (from the Wuhan Environmental Monitoring Center) during the same periods. In the present study, a cold spell was defined as 5 or more consecutive days with daily average temperatures below the 5th percentile of daily mean temperatures (2.58 ℃) from January to December in 2001-2011. A distributed lag nonlinear model (DLNM) was applied to assess the acute effect of cold spells on daily nonaccidental mortality.

RESULTS

During the study period, the total number of nonaccidental deaths was 17 119, including 9 403 (75.5%) among individuals aged over 65 years; 7 968 (46.5%) people died of cardiovascular disease. According to this definition, there were a total of 13 cold spell events and 111 days of duration in Wuhan during the study period. Study days were divided into three periods: non-cold spell days, 2008 cold spell days, and cold spell days in other years. Average daily mean temperatures of the above three periods were (8.2±4.5), (-0.7±1.4), and (0.8±1.2) ℃, respectively, corresponding to average daily deaths of 14.0±4.2, 18.2±4.5, and 14.9±4.9 for nonaccidental mortality. After adjusting for long-term trends, seasonal trends, weekdays, holidays, and relative humidity, analysis by the DLNM revealed that cold spells were associated with increased mortality risk, with a cumulative relative risk (RR) of 1.56 (95% CI: 1.36-1.79) at lag 0-27 days in 2008, higher than that in other years with 1.23 (95%CI: 1.08-1.41). Cold spells were not significantly associated with respiratory mortality and people under 65 years of age; however, during the 2008 cold spell RR increased to 1.96 (95% CI: 1.62-2.37) and 1.67 (95% CI: 1.43-1.95) for cardiovascular mortality and older adults (≥65 years old), respectively; both males and females had high mortality risk, with RRs of 1.60 (95%CI:1.33-1.92) and 1.50 (95% CI: 1.23-1.84), respectively. The association between cold spells and mortality remained nearly unchanged with and without adjustment for ambient pollutants (PM10, SO2, and NO2) in the DLNMs.

CONCLUSION

In Wuhan, both the 2008 cold spell and cold spells in other years were significantly associated with increased nonaccidental mortality. People with cardiovascular disease and elderly adults may be more susceptible to the impact of cold spells on mortality.

Signal Transduction Pathways of EMT Induced by TGF-β, SHH, and WNT and Their Crosstalks

Epithelial-to-mesenchymal transition (EMT) is a key step in development, wound healing, and cancer development. It involves cooperation of signaling pathways, such as transformation growth factor-β (TGF-β), Sonic Hedgehog (SHH), and WNT pathways. These signaling pathways crosstalk to each other and converge to key transcription factors (e.g., SNAIL1) to initialize and maintain the process of EMT. The functional roles of multi-signaling pathway crosstalks in EMT are sophisticated and, thus, remain to be explored. In this review, we focused on three major signal transduction pathways that promote or regulate EMT in carcinoma. We discussed the network structures, and provided a brief overview of the current therapy strategies and drug development targeted to these three signal transduction pathways. Finally, we highlighted systems biology approaches that can accelerate the process of deconstructing complex networks and drug discovery.

Phloroglucinol protects the urinary bladder via inhibition of oxidative stress and inflammation in a rat model of cyclophosphamide-induced interstitial cystitis

Background:

Phloroglucinol plays an important role in oxidative stress and inflammatory responses. The effects of phloroglucinol have been proven in various disease models. The aim of the present study was to investigate the efficacy and possible mechanisms of phloroglucinol in the treatment of interstitial cystitis (IC).

Methods:

Thirty-two female Sprague-Dawley (SD) rats were used in this study. IC was induced by intraperitoneal injection of cyclophosphamide (CYP). Rats were randomly allocated to one of four groups (n = 8 per group): A control group, which was injected with saline (75 mg/kg; i.p.) instead of CYP on days 1, 4, and 7; a chronic IC group, which was injected with CYP (75 mg/kg; i.p.) on days 1, 4, and 7; a high-dose (30 mg/kg) phloroglucinol-treated group; and a low-dose (15 mg/kg) phloroglucinol-treated group. On day 8, the rats in each group underwent cystometrography (CMG), and the bladders were examined for evidence of oxidative stress and inflammation. Statistical analysis was performed by analysis of variance (ANOVA) followed by least square difference multiple comparison post-hoc test.

Results:

Histological evaluation showed that bladder inflammation in CYP-treated rats was suppressed by phloroglucinol. CMG revealed that the CYP treatment induced overactive bladder in rats that was reversed by phloroglucinol. Up-regulated tumor necrosis factor-α and interleukin-6 expression in the CYP-treated rats were also suppressed in the phloroglucinol treated rats. CYP treatment significantly increased myeloperoxidase activity as well as the decreased activities of catalase of the bladder, which was reversed by treatment with phloroglucinol.

Conclusions:

The application of phloroglucinol suppressed oxidative stress, inflammation, and overactivity in the bladder. This may provide a new treatment strategy for IC.

Berberine ameliorates renal interstitial fibrosis induced by unilateral ureteral obstruction in rats

AIM

To investigate the potential effects of berberine on renal interstitial fibrosis (RIF) of obstructed kidneys in a unilateral ureteral obstruction (UUO) rat model.

METHODS

Forty-eight rats were randomly divided into three groups: sham-operated, vehicle-treated UUO, and berberine-treated UUO. Rats were gavaged with berberine (200 mg/kg per day) or vehicle. Eight randomly chosen rats in each group were kiled and specimens were collected at day 14 after UUO. Physiological parameters and histological changes were assessed, RIF was evaluated using Masson's trichrome and Sirius red staining, oxidative stress and inflammation markers were determined, transforming growth factor β1 (TGF-β1), phosphorylated Smad3 (pSmad3) and α-smooth muscle actin (α-SMA) were measured using immunohistochemistry or western blotting analysis. The obstruction was relieved at day 14 by percutaneous nephrostomy in the remaining UUO rats. The resistive index of left kidneys was undertaken by coloured Doppler flow imaging at day 14 before nephrostomy and day 7 after the relief.

RESULTS

Berberine treatment significantly attenuated RIF induced by UUO. The UUO-induced reduction in kidney superoxide dismutase and catalase activities increased, whereas elevated kidney malondialdehyde level markedly decreased. Berberine treatment significantly ameliorated UUO-induced inflammation, and decreased TGF-β1, pSmad3 and α-SMA expression of UUO kidneys. Moreover, berberine treatment significantly suppressed the increase of resistive index compared with UUO group at day 14 after UUO as well as day 7 after the relief of obstruction.

CONCLUSION

Berberine treatment ameliorates RIF in a UUO rat model by inhibition of oxidative stress, inflammatory responses, and TGF-β1/pSmad3 signalling.

Development of novel and polymorphic microsatellite DNA loci from Haliotis ovina

Twelve microsatellite loci were developed from Haliotis ovina by the magnetic bead hybridization method. Genetic variability was assessed using 30 individuals from 3 wild populations. The number of alleles per locus ranged from 2 to 5, and the polymorphism information content ranged from 0.1228 to 0.6542. Observed and expected heterozygosities ranged from 0.0000 to 0.7778 and 0.1288 to 0.6310, respectively. These loci should provide useful information for genetic studies such as genetic diversity, pedigree analysis, construction of genetic linkage maps, and marker-assisted selection breeding in H. ovina.

Epigenetic state network approach for describing cell phenotypic transitions

Recent breakthroughs of cell phenotype reprogramming impose theoretical challenges on unravelling the complexity of large circuits maintaining cell phenotypes coupled at many different epigenetic and gene regulation levels, and quantitatively describing the phenotypic transition dynamics. A popular picture proposed by Waddington views cell differentiation as a ball sliding down a landscape with valleys corresponding to different cell types separated by ridges. Based on theories of dynamical systems, we establish a novel 'epigenetic state network' framework that captures the global architecture of cell phenotypes, which allows us to translate the metaphorical low-dimensional Waddington epigenetic landscape concept into a simple-yet-predictive rigorous mathematical framework of cell phenotypic transitions. Specifically, we simplify a high-dimensional epigenetic landscape into a collection of discrete states corresponding to stable cell phenotypes connected by optimal transition pathways among them. We then apply the approach to the phenotypic transition processes among fibroblasts (FBs), pluripotent stem cells (PSCs) and cardiomyocytes (CMs). The epigenetic state network for this case predicts three major transition pathways connecting FBs and CMs. One goes by way of PSCs. The other two pathways involve transdifferentiation either indirectly through cardiac progenitor cells or directly from FB to CM. The predicted pathways and multiple intermediate states are supported by existing microarray data and other experiments. Our approach provides a theoretical framework for studying cell phenotypic transitions. Future studies at single-cell levels can directly test the model predictions.

Coupled reversible and irreversible bistable switches underlying TGFβ-induced epithelial to mesenchymal transition

Epithelial to mesenchymal transition (EMT) plays an important role in embryonic development, tissue regeneration, and cancer metastasis. Whereas several feedback loops have been shown to regulate EMT, it remains elusive how they coordinately modulate EMT response to TGF-β treatment. We construct a mathematical model for the core regulatory network controlling TGF-β-induced EMT. Through deterministic analyses and stochastic simulations, we show that EMT is a sequential two-step program in which an epithelial cell first is converted to partial EMT then to the mesenchymal state, depending on the strength and duration of TGF-β stimulation. Mechanistically the system is governed by coupled reversible and irreversible bistable switches. The SNAIL1/miR-34 double-negative feedback loop is responsible for the reversible switch and regulates the initiation of EMT, whereas the ZEB/miR-200 feedback loop is accountable for the irreversible switch and controls the establishment of the mesenchymal state. Furthermore, an autocrine TGF-β/miR-200 feedback loop makes the second switch irreversible, modulating the maintenance of EMT. Such coupled bistable switches are robust to parameter variation and molecular noise. We provide a mechanistic explanation on multiple experimental observations. The model makes several explicit predictions on hysteretic dynamic behaviors, system response to pulsed stimulation, and various perturbations, which can be straightforwardly tested.

Statistical mechanics model for the dynamics of collective epigenetic histone modification

Epigenetic histone modifications play an important role in the maintenance of different cell phenotypes. The exact molecular mechanism for inheritance of the modification patterns over cell generations remains elusive. We construct a Potts-type model based on experimentally observed nearest-neighbor enzyme lateral interactions and nucleosome covalent modification state biased enzyme recruitment. The model can lead to effective nonlocal interactions among nucleosomes suggested in previous theoretical studies, and epigenetic memory is robustly inheritable against stochastic cellular processes.

Reduced expression of Slit2 in renal cell carcinoma

Slit2, initially identified as an important axon guidance molecule in the nervous system, was suggested to be involved in multiple cellular processes. Recently, Slit2 was reported to function as a potential tumor suppressor in diverse tumors. In this study, we systematically analyzed the expression level of Slit2 in renal cell carcinoma. Compared to paired adjacent non-malignant tissues, both Slit2 mRNA and protein expression were significantly down-regulated in renal cell carcinoma (RCC). Methylation-specific PCR showed that Slit2 promoter was methylated in two renal carcinoma cell lines. Pharmacologic demethylation dramatically induced Slit2 expression in cancer cell lines with weak expression of Slit2. Besides, bisulfite genomic sequencing confirmed that dense methylation existed in Slit2 promoter. Furthermore, in paired RCC samples, Slit2 methylation was observed in 8 out of 38 patients (21.1 %), which was well correlated with the down-regulation of Slit2 in RCC. Therefore, Slit2 may also be a potential tumor suppressor in RCC, which is down-regulated in RCC partially due to promoter methylation.

The tumor-suppressive function of UNC5D and its repressed expression in renal cell carcinoma

PURPOSE

As a newly added member of the UNC5H receptors, the function of UNC5D/H4 in tumorigenesis remains poorly defined. The aim of this study was to examine the expression of UNC5D in primary renal cell carcinomas (RCC), analyze the mechanisms responsible for its downregulation in RCC, and assess its functional relevance to tumor growth and migration.

EXPERIMENTAL DESIGN

Forty-four paired primary RCCs and corresponding adjacent noncancerous tissues were collected. The mRNA and protein expression level of UNC5D was assessed by reverse transcriptase-PCR, real-time PCR, or immunohistochemistry. Epigenetic alterations in UNC5D promoter and LOH in the UNC5D locus were also analyzed. Ectopic expression of UNC5D in renal cancer cells with silenced expression of UNC5D was used for analysis of the biologic functions of UNC5D.

RESULTS

UNC5D expression was attenuated in multiple carcinoma cell lines including renal cancer cells. Similar reduction was also observed in primary RCC tissues as compared with paired adjacent noncancerous tissues. Methylation-specific PCR showed hypermethylation in UNC5D promoter in a significant proportion (18 of 44) of tumor tissue (40.9%). LOH of UNC5D was observed in 13 of 44 patients with RCCs (29.5%). Restoration of UNC5D expression in renal cancer cells significantly inhibited cell proliferation, anchorage-dependent and -independent growth, as well as migration and invasion, whereas knockdown of UNC5D promoted cell growth. Furthermore, ectopic expression of UNC5D induced G2-M cell-cycle arrest.

CONCLUSIONS

UNC5D is a functional tumor suppressor that is frequently downregulated in RCCs due to promoter hypermethylation and LOH.

Biodegradation of 3-nitrotoluene by Rhodococcus sp. strain ZWL3NT

A pure bacterial culture was isolated by its ability to utilize 3-nitrotoluene (3NT) as the sole source of carbon, nitrogen, and energy for growth. Analysis of its 16S rRNA gene showed that the organism (strain ZWL3NT) belongs to the genus Rhodococcus. A rapid disappearance of 3NT with concomitant release of nitrite was observed when strain ZWL3NT was grown on 3NT. The isolate also grew on 2-nitrotoluene, 3-methylcatechol and catechol. Two metabolites, 3-methylcatechol and 2-methyl-cis,cis-muconate, in the reaction mixture were detected after incubation of cells of strain ZWL3NT with 3NT. Enzyme assays showed the presence of both catechol 1,2-dioxygenase and catechol 2,3-dioxygenase in strain ZWL3NT. In addition, a catechol degradation gene cluster (catRABC cluster) for catechol ortho-cleavage pathway was cloned from this strain and cell extracts of Escherichia coli expressing CatA and CatB exhibited catechol 1,2-dioxygenase activity and cis,cis-muconate cycloisomerase activity, respectively. These experimental evidences suggest a novel pathway for 3NT degradation with 3-methylcatechol as a key metabolite by Rhodococcus sp. strain ZWL3NT.

A two-step mechanism for cell fate decision by coordination of nuclear and mitochondrial p53 activities

The tumor suppressor p53 has a crucial role in the DNA damage response. Here, we proposed an integrated model of the p53 network and explored how the nuclear and mitochondrial p53 pathways are coordinated to determine cell fates after -irradiation in radiosensitive tissues. Using numerical simulations, we found that depending on the extent of DNA damage, cells may survive, commit apoptosis after cell cycle arrest, or undergo apoptosis soon after irradiation. There exists a large cell-to-cell variability in outcome because of stochasticity in the generation and repair of DNA damage as well as cellular heterogeneity. At the cell population level, there occur two waves of apoptosis: a fast wave mediated by mitochondrial p53 within three hours postirradiation, and a slow wave mediated by nuclear p53 after eight hours postirradiation. Thus, we propose a two-step mechanism for cell fate decision. The first step is to decide whether DNA damage is severe enough to trigger apoptosis directly through the mitochondrial p53 pathway, while the second step is to determine whether the damage is fixed after cell cycle arrest. Such a mechanism may represent an efficient and reliable control mode, avoiding unnecessary death or greatly promoting the execution of apoptosis. It was also demonstrated that nuclear p53 can inhibit the pro-apoptotic activity of mitochondrial p53 by transactivating p21, and Mdm2 can facilitate apoptosis by promoting the mono-ubiquitination of p53. These results are either in good agreement with experimental observations or experimentally testable. Our work suggests that both the transcription-independent and -dependent p53 activities are indispensable for a reliable choice of cell fate and also provides clues to therapeutic manipulation of the p53 pathway in cancer treatment.

Genetic and epigenetic control of UNC5C expression in human renal cell carcinoma

Inappropriate gene silencing and subsequent promiscuous activity define the transformation of many solid tumours including renal cell carcinoma (RCC). Here, we report that UNC5C, one of the Netrin-1 receptors, was frequently inactivated in RCC cell lines and primary tumours. UNC5C protein was expressed in the proximal convoluted tubules of the human kidney, the presumed origin of clear cell RCC (ccRCC) and papillary RCC (pRCC). Compared to paired adjacent non-malignant tissues, both UNC5C mRNA and protein expression were significantly down-regulated in RCC. Immunohistochemical analysis showed that UNC5C was inactivated in 94.3% of the samples and the loss of UNC5C occurred at the early stage of RCC. Methylation specific PCR showed that UNC5C promoter was methylated in two renal carcinoma cell lines. Pharmacologic demethylation alone or in combination with inhibition of deacetylation dramatically induced UNC5C expression. Furthermore, bisulfite genomic sequencing (BGS) confirmed that dense methylation existed in UNC5C promoter. In paired tumour samples, UNC5C methylation was observed in 12 out of 44 patients (27.3%). Moreover, we analysed the loss of heterozygosity (LOH) of UNC5C in renal cell carcinoma, the LOH was observed in 27 out of 44 patients (61.4%). Finally, restoration of UNC5C expression suppressed the colony formation of renal carcinoma cells. In addition, UNC5C inhibited tumour cell proliferation, migration and enhanced chemosensitivity to cisplatin and etoposide. Therefore, UNC5C acts as a tumour suppressor in RCC and is down-regulated in RCC. Loss of heterozygosity and DNA methylation contribute to the inactivation of UNC5C in renal cell carcinoma.

Interlinking positive and negative feedback loops creates a tunable motif in gene regulatory networks

Positive and negative feedback loops are often coupled to perform various functions in gene regulatory networks, acting as bistable switches, oscillators, and excitable devices. It is implied that such a system with interlinked positive and negative feedback loops is a flexible motif that can modulate itself among various functions. Here, we developed a minimal model for the system and systematically explored its dynamics and performance advantage in response to stimuli in a unifying framework. The system indeed displays diverse behaviors when the strength of feedback loops is changed. First, the system can be tunable from monostability to bistability by increasing the strength of positive feedback, and the bistability regime is modulated by the strength of negative feedback. Second, the system undergoes transitions from bistability to excitability and to oscillation with increasing the strength of negative feedback, and the reverse conversion occurs by enhancing the strength of positive feedback. Third, the system is more flexible than a single feedback loop; it can produce robust larger-amplitude oscillations over a wider stimulus regime compared with a single time-delayed negative feedback loop. Furthermore, the tunability of the system depends mainly on the topology of coupled feedback loops but less on the exact parameter values or the mode of interactions between model components. Thus, our results interpret why such a system represents a tunable motif and can accomplish various functions. These also suggest that coupled feedback loops can act as toolboxes for engineering diverse functional circuits in synthetic biology.

[Gene cloning, sequence analysis and tissue expression of estrogen-related receptor alpha (Erralpha) in Japanese medaka and its transcriptional responses after differential EDCs exposure]

Endocrine disrupting chemicals (EDCs) can bind or block nuclear receptors in the body and subsequently affect growth, development and reproduction of fish. Estrogen-related receptors (ERRs), belonging to the nuclear receptor superfamily, have been implicated in diverse physiological processes in estrogen signal pathway in mammals, while little is known about them in fishes. Complete mRNA sequence of ERRalpha from medaka (Oryzias latipes) was cloned, and the sequence is similar to those of other vertebrates, especially that the DNA-binding domain (DBD) of ERRalpha is highly conserved among the vertebrates (97.4%-100% sequence identities) and the ligand-binding domain (LBD) of medaka ERRalpha is 66.4%-67.0% sequence identities with those of mammals. The DBD of medaka ERRalpha is of the same length and has high sequence identity with those of estrogen receptor (ERalpha and ERbeta) and androgen receptor (ARalpha and ARbeta) of medaka, but much difference was found between the LBD of medaka ERRalpha with those of ERalpha, ERbeta, ARalpha and ARbeta. ERRalpha gene is located in chromosome 14 and is consisted of 5 exons. The expressions of ERRalpha in different tissues and the transcriptional responses of ERRalpha in testis of medaka exposed differential EDCs were studied by quantitative real-time RT-PCR. ERRalpha is expressed at apparently high levels in gonad, brain, eye, spleen and intestine, though it was broadly expressed in tissues. Significant transcriptional difference was found between testis and ovary, implying ERRalpha would be involved in sex differentiation and gonad development in fish. After 3 weeks exposure of medaka to 200 ng/L ethynylestradiol (EE2), 200 ng/L estrone (E1), 200 ng/L diethylstilbestrol (DES), 100 microg/L atrazine (AT) and 200 ng/L 17beta-estradiol (E2), transcripts of ERRalpha were significantly decreased to 0.54, 0.56, 0.61, 0.63 and 0.65 of control (p < 0.05) in the testes, respectively. And those in the 1 microg/L tributyltin (TBT) and 1 microg/L triphenyltin (TPT) exposure groups were up-regulated to 1.34 and 1.35 folds of control (p > 0.05), respectively. These results suggested that ERRalpha would take actions in the disruption of sex differentiation and gonad development in fish by EDCs. In addition, no multiple steroid hormone-response element half-sites was found in medaka, which were reported in the upstream of ERRalpha gene in mammals, indicating there would be different regulation patters of ERRalpha between teleost and mammal.

[Establishment of two-dimensional differential gel electrophoresis using cerebrospinal fluid from neurocysticercosis patients]

OBJECTIVE

To establish the method of two-dimensional differential gel electrophoresis and obtain high resolution 2D images from cerebrospinal fluid (CSF) of patients with neurocysticercosis.

METHODS

CSF samples were collected from four patients diagnosed as neurocysticercosis clinically and by ELISA, computed tomography (CT) or magnetic resonance imaging (MRI), and from four healthy subjects without neurological disorders. The CSF samples were precipitated with cold acetone, then pooled by equal amount as patients and controls. The internal standard comprised equal amounts of proteins extracted from both groups. Internal standard, and proteins from the two groups were labeled prior to electrophoresis with spectrally resolvable fluorescent dyes, cyanein dye2 (Cy2), Cy3 and Cy5. Sodium dodecylsulfonate polyacrylamide gel chromatography (SDS-PAGE) and two-dimensional differential in-gel electrophoresis (2-D DIGE) of labeled samples were then run. The differential expressed proteins showed in the images of SDS-PAGE and 2-D DIGE gels scanned with 488 nm, 532 nm and 633 nm wavelength laser were analyzed by ImageQuant and DeCyde 5.0 respectively. Spot detection and quantification was performed for the differential in-gel analysis (DIA) module of DeCyder. Biological variation analysis (BVA) module of DeCyder was matched gel 1 and gel 2 images to provide data on differential protein expression levels between the two groups.

RESULTS

The ImageQuant result displayed that the CSF protein was compatible with the dye, and the difference of protein amount was revealed by the difference of fluorescence intensity. DIA indicated that there were 896 and 894 protein dots on gel 1 and gel 2 respectively, and 90% of them were matched each other. BVA showed that there were 55 protein spots with different expressional level between neurocysticercosis and control groups. Protein spots with two-fold increase or decrease were 47 and 8 respectively in neurocysticercosis patients compared with healthy controls.

CONCLUSION

The method of 2-D DIGE has been established with high-resolution images for the examination of cerebrospinal fluid, providing a foundation for further study of neurocysticercosis comparative proteomics.

[Production of transgenic lamb integrated with modified human anti-trypsin gene]

This experiment is to produce the human mAAT(modified anti-trypsin) which cures the emphysema specifically through mammalian galactophore of transgenic goat. 56 goats were selected as donor for superovulation by FSF + LH microinjection in this experiment. The pronucleic embryos were injected with human mAAT gene after fertilization in vivo, and transferred to the donors or receptors directly. The superovulation was better in March and May than in December with the number of ovulation of 19.50, 21.70 and 16.06, and number of fertilized embryos of 4.31, 6.48 and 3.57 per-animal respectively. The pregnant rates were 18.18% and 25% respectively after transferred to donors and receptors with natural estrus. The donors also can be used as the embryo receptor with no remarkable decrease of pregnant rate. 29 lamb were labored. 4 positive transgenic lamb were checked by PCR, PCR-Southern and Southern analysis. The integrated efficiency of foreign DNA was 13.79% with microinjection of high copy number of foreign DNA fragment.