[Characteristics of electrocardiogram in fulminant myocarditis].

Objective: To investugate the unique electrocardiogram (ECG) characteristics of fulminant myocarditis (FM) patients and provide important clues for the diagnosis of FM. Methods: This was a retrospective study. Patients diagnosed with acute myocarditis at Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology from February 2017 to April 2022 were enrolled and divided into fulminant myocarditis group (FM) and non-fulminant myocarditis group (NFM) according to clinical diagnosis. A total of 246 healthy people who underwent physical examination in the Health examination Center of Tongji Hospital at the same period were selected as the control group. The clinical data and ECG characteristics of the above 3 groups were analyzed and compared. Logistic regression model was used to analyze the influence of ECG parameters on left ventricular ejection fraction in FM patients. Receiver operating curves were constructed to evaluate the predictive value of different ECG parameters for FM. Results: A total of 180 patients were included in this study (FM group: n=123; NFM group: n=57), with an age of (35.0±16.2) years and 106 males (58.89%). Compared with NFM group, ECG was significantly abnormal in FM group, with a higher incidence of sinus tachycardia, ventricular tachycardia or ventricular fibrillation, escape rhythm, right bundle branch block, third degree atrioventricular block, ST-segment elevation, low voltage, prolonged QTc interval, and widened QRS wave in the FM group (all P<0.05). The ECG parameters showed that the amplitude of the full lead QRS wave in FM group was lower than that in NFM group (P<0.01). The average heart rate and QTc interval of FM group were significantly higher than those of NFM and control groups (all P<0.05). Although ST-segment elevation had a higher incidence in the FM group, ECG parameters showed that except for leads Ⅲ and aVF, the ST segment levels in all leads in the FM group were lower than those in the control group (all P<0.05). There was a statistically significant difference in some ST segment changes between FM and NFM groups, while there was no statistical difference between the NFM and control groups. Multivariate regression analysis showed that widened QRS wave and increased heart rate were the influencing factors for left ventricular systolic dysfunction in FM patients (OR=16.914, 95%CI: 1.367-209.224, P=0.028; OR=1.026, 95%CI: 1.010-1.042, P=0.001). Receiver operating curve analysis showed that heart rate>86.90 beat/min, QTc>431.50 ms, and RV5+SV1<1.72 mV had certain predictive value for FM diagnosis. Conclusions: FM patients displayed marked and severe ECG abnormalities, and characteristic changes in ECG can provide important first clues for the diagnosis of FM.

[Chronic non-bacterial osteomyelitis with autoimmune hepatitis: a case report and literature review].

Objective: To summarize the clinical characteristics and treatments of chronic non-bacterial osteomyelitis with autoimmune hepatitis in children. Methods: A child who had chronic non-bacterial osteomyelitis with autoimmune hepatitis was admitted to the Department of Gastroenterology of the Children's Hospital Capital Institute of Pediatrics at April 2022. The clinical data was retrospectively analyzed. Using the keywords of "chronic non-bacterial osteomyelitis""autoimmune hepatitis" in Chinese and English, the literature from database establishment to December 2022 in CNKI, Wanfang, China Biomedical Literature Database and Pubmed was searched. Combined with this case, the clinical characteristics and treatment of chronic non-bacterial osteomyelitis combined with autoimmune hepatitis were analyzed. Results: A 5 years and 3 months girl was admitted to the Department of Gastroenterology of Children's Hospital, Capital Institute of Pediatrics for "transaminase elevated for 1 year and swelling of right maxillofacial area for half a year". The physical examinations at admission found a 4.0 cm × 4.0 cm swelling area with tenderness before the right ear, abdominal distention with visible abdominal wall vein, firm and enlarged liver (10.0 cm below the xiphoid and 4.5 cm below the right ribs), and splenomegaly (Line Ⅰ 10.0 cm, Line Ⅱ 11.5 cm, and Line Ⅲ 25.0 cm). There was no redness, swelling or restriction of the limbs. Laboratory examination found abnormal liver function with alanine aminotransferase 118 U/L, aspartate aminotransferase 227 U/L, γ-glutamyltransferase 360 U/L, and positive direct anti-human globulin test; immunology test found immunoglobulin G 41.60 g/L and a homogeneous type of antinuclear antibody of 1∶1 000; the autoimmune hepatitis antibody test found a positive anti-smooth muscle antibody (1∶100). Liver biopsy showed moderate interfacial inflammation and the patient was diagnosed with autoimmune hepatitis (International Autoimmune Hepatitis Group 19). The imaging findings showed extensive involvement of the bilateral mandible, while the right side was severe. There were expansile bone changes, thinning of the bone cortex, and significant swelling of the surrounding soft tissue in the mandibular body, mandibular angle, and mandibular ramus. After treatment of glucocorticoid, the swelling of the right maxillofacial region disappeared and the transaminase returned to normal. Only one case was reported before in English and none in Chinese. The two cases were both girls whose main clinical features were joint pain and swelling. The previous case started with pain in both knee joints, and developed liver injury during treatment while this case had liver injury as the initial clinical presentation. Besides, the affected sites and degrees of arthritis in the 2 cases were different. After glucocorticoid treatment, the clinical symptoms were alleviated, and transaminases returned to normal. Conclusions: Chronic non bacterial osteomyelitis may involve the liver and manifest as autoimmune hepatitis. Glucocorticoids therapy is effective.

[Factors affecting BK polyomavirus infection after kidney transplantation in post-school children and a predictive infection model].

Objective: To analyze high-risk factors affecting BK polyomavirus (BKPyV) infection and to construct a prediction model for BKPyV infection in children after renal transplantation. Methods: The clinical data of 332 children who received allogeneic kidney transplantation in the First Affiliated Hospital of Zhengzhou University from January 2014 to March 2022 were retrospectively collected. According to the BKPyV load level, the dynamic change process of lymphocytes at different time points were analyzed. The factors that have potential influence on BKPyV infection were screened by Cox regression analysis, and the receiver operating characteristic curve (ROC) was used to evaluate the sensitivity and specificity of the predictive model of infection. Results: Among the 332 children, there were 215 males and 117 females; the age of transplantation was (12.2±3.9) years old; 37 cases were preschool (1-5 years old), and 295 cases were post-school age (6-18 years old). BKPyV load in 224 urine samples and 30 blood samples of children were detected. There were 9 cases of BKPyV-associated viruria and 3 cases of BKPyV associated viremia in pre-school children, 76 cases BKPyV associated viruria and 14 cases of BKPyV associated viremia in post-school children. Multivariate Cox regression analysis showed that higher body mass index (BMI) (HR=1.105, 95%CI: 1.020-1.197), antithyroglobulin (ATG) application (HR=2.196, 95%CI: 1.335-3.613), and higher tacrolimus concentration (HR=2.484, 95%CI: 1.298-4.753), higher natural killer (NK) lymphocyte count (HR=1.193, 95%CI: 1.009-1.411), higher CD14++CD16-cell count (HR=1.096, 95%CI: 1.024-1.173) were independent risk factors for BKPyV associated viruria in post-school children. Delayed graft function (DGF) (HR=4.993, 95%CI: 1.555-16.038), Acute rejection (AR) (HR=6.021, 95%CI: 1.930-18.787), higher CD14++CD16-cell count (HR=1.227, 95%CI: 1.081-1.392) were independent risk factors for BKPyV associated viremia in post-school children. The results of ROC curve analysis showed that combined BMI, immune induction drugs, tacrolimus concentration, NK cell count, and CD14++CD16-cell count predicted the occurrence of BKPyV associated viruria in post-school children after kidney transplantation at 0.5, 1, 2, and 5 years with area under curve (AUC) of 0.712 (95%CI: 0.626-0.798), 0.708 (95%CI: 0.612-0.804), 0.754 (95%CI: 0.668-0.840) and 0.767 (95%CI: 0.685-0.849). The sensitivity and specificity of the model were 64.9%, 61.4%, 61.6%, 55.8% and 70.9%, 72.4%, 76.0%, 84.0%, respectively. Combined with DGF, AR, and CD14++CD16-cell counts predicted the occurrence of BKPyV-associated viremia at 0.5, 1, 2, and 5 years after renal transplantation in post-school children with AUC of 0.791 (95%CI: 0.631-0.951), 0.744 (95%CI: 0.547-0.936), 0.786 (95%CI: 0.629-0.946) and 0.812 (95%CI: 0.672-0.948). The sensitivity and specificity of the model were 76.1%, 67.1%, 75.0%, 77.9% and 88.9%, 89.0%, 89.9%, 88.0%, respectively. Conclusions: The postoperative CD14++CD16-cell level can be used as an independent predictor of BKPyV infection in post-school children after renal transplantation. Combined BMI, immune induction drugs, tacrolimus concentration, NK cell count, CD14++CD16-cell count and combined DGF, AR, CD14++CD16-cell count show good fitting effect in predicting the occurrence of BKPyV-associated viruria and viremia after transplantation in post-school children respectively.

[Current status and challenges of long-term safety evaluation of using tests of cosmetics on human body].

The use of cosmetics in the crowd has the long-term characteristics. The adverse reactions of cosmetics reported in other country in the world suggest that human patch tests and short-term human using test may not be sufficient to evaluate the safety of high-risk new cosmetic raw ingredients, and long-term human using test should be conducted for evaluation. Therefore, this article reviews the key factors that affect long-term human trial trials, such as site of use, single-use amount, frequency of use, duration of use, and subject conditions, providing supportive evidence for standardized safety evaluation standards for long-term human using test of cosmetics.

WWOX regulates the Elf5/Snail1 pathway to affect epithelial-mesenchymal transition of ovarian carcinoma cells in vitro.

OBJECTIVE: Ovarian cancer is a highly invasive type of cancer. A previous study demonstrated that E-cadherin expression was upregulated in a human ovarian cancer cell line with a high expression of WW domain-containing oxidoreductase (WWOX), which is a tumor suppressor. Also, the migration and invasion ability of these cells was reduced. Snail family members are involved in the epithelial-to-mesenchymal transition (EMT) of ovarian cancer cells, and the expression of Snail family members is regulated by the transcription factor Elf5. The aim of the present research was to elucidate the role of WWOX in EMT of ovarian carcinoma cells through the Elf5/Snail pathway by gain and loss of function approaches in in vitro experiments. MATERIALS AND METHODS: First, a WWOX gene expressing plasmid was transfected into CD133+CD117+ HO8910 ovarian carcinoma cells, and an Elf5 shRNA plasmid was transfected into these cells to assess the changes in EMT-related factors, including Snail1, and the invasive ability of tumor cells ability. Second, the human ovarian carcinoma cell lines HO8910 and SKOV3 were divided into six groups to detect the same indicators. RESULTS: The results demonstrated that the high expression of WWOX resulted in an increased E-cadherin expression, decreased Snail1 activity, and decreased invasion ability in CD133+CD117+ HO8910 cells. Elf5 shRNA transfection did not affect the WWOX expression; however, it decreased the expression of E-cadherin and Elf5 activity, while increasing Snail1 activity and invasion ability in CD133+CD117+ HO8910 cells. It was also observed that WWOX overexpression in HO8910 and SKOV3 cells inhibited the expression of EMT-related proteins and inhibited cell migration and invasion. CONCLUSIONS: Taken together, the results of the present report suggest that WWOX can decrease Snail1 activity by enhancing the activity of Elf5, thus upregulating E-cadherin expression and eventually inhibiting EMT of ovarian carcinoma.

Response of ecosystem CO2 fluxes to grazing intensities - a five-year experiment in the Hulunber meadow steppe of China.

Grazing is the primary land use in the Hulunber meadow steppe. However, the quantitative effects of grazing on ecosystem carbon dioxide (CO2) fluxes in this zone remain unclear. A controlled experiment was conducted from 2010 to 2014 to study the effects of six stocking rates on CO2 flux, and the results showed that there were significant differences in CO2 fluxes by year, treatment, and month. The effects of light and intermediate grazing remained relatively constant with grazing year, whereas the effects of heavy grazing increased substantially with grazing duration. CO2 flux significantly decreased with increasing grazing intensity and duration, and it was significantly positively correlated with rainfall, soil moisture (SM), the carbon to nitrogen ratio (C/N ratio), soil available phosphorus (SAP), soil NH4+-N, soil NO3-N, aboveground biomass (AGB), coverage, height, and litter and negatively correlated with air temperature, total soil N (TN) and microbial biomass N (MBN). A correspondence analysis showed that the main factors influencing changes in CO2 emissions under grazing were AGB, height, coverage, SM, NH4+-N and NO3-N. Increased rainfall and reduced grazing resulted in greater CO2 emissions. Our study provides important information to improve our understanding of the role of livestock grazing in GHG emissions.

[Role of magnetic resonance imaging in the diagnosis of juvenile dermato-myositis and polymyositis in Chinese children].

Objective: To evaluate the utility of magnetic resonance imaging (MRI) in diagnosis of juvenile dermatomyositis and polymyositis (JDM-PM) in children. Method: Fifty-four patients with JDM-PM in the active stage were enrolled in the study group. Twelve patients with benign acute childhood myositis and forty patients with juvenile idiopathic arthritis (JIA) complicated with myositis were enrolled as controls. MRI imaging of thighs was performed in all patients, fast spin echo T1WI, T2WI, and STIR were obtained in all patients.Muscle biopsy was performed in 41/54 patients with JDM-PM. We compared the value of MRI in diagnosis of JDM-PM with muscle biopsy, electromyography and serum aspartate transaminase (AST), alanine transaminase (ALT), creatine kinase (CK), isoenzyme of creatine kinase (CKMB), lactate dehydrogenase (LDH), hydroxybutyrate dehydrogenase (HBDH) levels. Continuous normally distributed variables were reported as means and continuous non-normally distributed variables as median. Chi-square test and Fisher exact test were used to test differences between MRI and other categorical variables. Result: A total of 54 patients were included. Twenty-seven patients were male and the others were female. Average age of the patients was (7.1±3.5) years (2-13 years); 45(83%) paitests were JDM cases and 9(17%) patients had JPM. All patients had MRI examination. Of the 54 patients, 53 had multiple myositis; 10 out of 50 (19%) patients received second MRI after treatment, 6 out of 10 patients had normal findings, 4 patients showed obviously improved images; 41 out of 54 patients underwent muscle biopsy; 22 out of 41 patients had inflammatory cells infiltration and muscle fiber degeneration. The results of the muscle enzyme tests are as follows: 27 (50%) patients had elevated AST, 24 (44%) patients had elevated ALT, 22 (41%) patients had elevated CK, 18(33%) patients had elevated CKMB, and LDH rose in 30 (56%) patients, HBDH rose in 28(52%) patients. These results suggested that muscle MRI was more sensitive than muscle biopsy and muscle enzyme tests in diagnosis of JDM-PM. Conclusion: Patients with JDM-PM showed diffuse patchy hyperintense signals on T2WI of their thighs. MRI may be a sensitive, reliable, and noninvasive tool for clinical diagnosis and theraputic evaluation of JDM-PM.

[The value of brain magnetic resonance imaging in the early diagnosis of neuropsychiatric systemic lupus erythematosus].

OBJECTIVE: To investigate the value of brain magnetic resonance imaging (MRI) in evaluating the intracranial injuries in patients with juvenile onset systemic lupus erythematosus (SLE). METHOD: Data of brain MRI, CT, electroencephalogram (EEG), cerebrospinal fluids analysis and clinical features of the central nervous system of 44 patients from March 2007 to March 2015 with juvenile onset SLE who were not treated with glucocorticoids (Gcs) and immunosuppressive agents (Is) were retrospectively analyzed and compared. RESULT: Twenty-seven out of 44 patients demonstrated abnormal signs on brain MRI, including encephalatrophy, cerebral infarction, demyelination, encephalorrhagia, vertebral arteriostenosis and abnormal signals on the brain diffusion-weighted imaging (DWI). Sixteen patients had clinical features of the central nervous system involvement, fifteen had continuous headache, nine had continuous dizziness, seven had convulsions, three had hemiplegia, one had blurred vision. Physical examination of the nervous system: ten patients had abnormal signs, all had cervical rigidity, five showed pyramidal sign, three showed loss of muscle tone, two with cranial neuropathies and one had paresthesia. EEG: Ten patients showed abnormal waves on EEG, all showed diffused slow-waves, and five showed sharp waves and spikes. Cerebrospinal fluids analysis: six patients had abnormal results, five of them had cell count elevation and one had cell count and protein elevation, while there was glucose and chloride degression. Brain CT: Eight patients received CT scan, two showed cerebral infarction. χ(2) test was used to compare the differences among head MRI, EEG, cerebrospinal fluid analysis, physical examination of the nervous system, clinical features of the nervous system, the difference was significant(χ(2)=12.055, P=0.001; χ(2)=19.627, P=0.001; χ(2)=3.859, P=0.049; χ(2)=12.055, P=0.001). CONCLUSION: Brain MRI may be a better method in early diagnosis of intracranial injuries than CT, EEG, cerebrospinal fluid analysis and physical examination of the nervous system. Patients with juvenile onset SLE should receive brain MRI after diagnosis in order to investigate the intracranial injuries. Abnormal signals on the DWI are the signs of active disease.

Association between anti-beta2 glycoprotein I antibodies and renal glomerular C4d deposition in lupus nephritis patients with glomerular microthrombosis: a prospective study of 155 cases.

Glomerular microthrombosis (GMT) is a common vascular change in patients with lupus nephritis (LN). The mechanism underlying GMT is still unknown. In our previous study, we found that the level of IgG anti-beta2 glycoprotein I (beta2GPI) antibodies was higher in the LN-GMT group than in the LN-non-GMT group, which indicated that anti-beta2GPI antibodies may play a role in GMT formation. Many studies have demonstrated that the activation of the classical complement pathway may play a critical role in fetal loss and aPL-induced thrombosis formation. To investigate whether complement activation plays a role in GMT formation and to evaluate its relationship with aPL, we prospectively investigated deposition of C4d in 155 renal biopsy specimens of LN patients. The results revealed a strong relationship between the intensity of glomerular C4d staining and the presence of microthrombi (p < 0.001). The detection rate of IgG anti-beta2GPI antibodies was higher in the LN-GMT group than in the LN-non-GMT group (p < 0.05). Further, the intensity of glomerular C4d staining was significantly related with IgG anti-beta2GPI antibodies (p < 0.05). The results of our study suggest that anti-beta2GPI antibodies may play a role in GMT formation, and this process might involve complement activation.

Biphasic effect of GABA on rat sperm acrosome reaction: involvement of GABA(A) and GABA(B) receptors.

The functional relationship between GABA(A) and GABA(B) receptors in regulating acrosome reaction (AR) of rat spermatozoa was demonstrated by studying the differential effects of a GABA(B) agonist and an antagonist on the process. AR rates were determined using the chlortetracycline staining assay. The induction of AR in rat sperm by GABA was found to be a biphasic phenomenon; i.e., AR rates increased with increasing GABA concentrations up to <5 micro M and at higher concentrations of the neurotransmitter (>5 micro M), there was a reductionin the AR rates. This biphasic phenomenon is apparently due to the differential interaction of the neurotransmitter with GABA receptor subtypes in a dose-dependent manner; i.e., GABA(A) receptors (stimulatory) are primarily activated at low concentration of GABA, while GABA(B) receptors (inhibitory) become activated at higher concentrations. This hypothesis is supported by the present findings that treatment with saclofen, a GABA(B) receptor antagonist, did not influence the AR rates effected by GABA at low concentrations; while the AR rates were maintained at the maximum level at higher concentrations of GABA, resulting in the elimination of the biphasic phenomenon. Baclofen, a GABA(B) receptor agonist, blocks the AR activating action of GABA at both low and high concentrations. It would appear that the induction of AR in rat sperm by GABA is regulated by the proportionality of activated GABA(A) and GABA(B) receptors acting as a yin-yang control.

Identification of GABA(B) receptor in rat testis and sperm.

gamma-Aminobutyric acid (GABA) can mimic and potentiate the action of progesterone in initiating the acrosome reaction (AR) of mammalian sperm, indicating that sperm contain receptors for GABA. This contention was validated by identifying the receptor (R) subtype, GABA(A)R, in mammalian sperm. In the present study a second subtype, GABA(B)R, was identified in rat testis and sperm. Total RNAs of rat testis and sperm were prepared and used as template to synthesize the respective cDNAs by the RT-PCR method. Two splice variants of the cDNA coding GABA(B)R1 (GABA(B)R1a and GABA(B)R1c) and GABA(B)R2 were identified. Extracts of rat testis, spermatogenic cells and sperm contained two proteins with estimated molecular sizes of 130 and 100 kDa, corresponding to GABA(B)R1a and GABA(B)R1c/lb, respectively, determined by Western blot using polyclonal anti-GABA(B)R1 antibody. By an indirect immunofluorescence technique, GABA(B)R1 was located on the head of rat sperm. The present finding is the first direct demonstration that mammalian sperm contain GABA(B)R.

Human sperm membrane protein (hSMP-1): a developmental testis-specific component during germ cell differentiation.

Serum was obtained from an infertile woman having antibodies with sperm agglutinating activity. The antibodies interacted with a human sperm membrane protein (hSMP-1) with an estimated Mr of 55 kD. The gene (HSD-1) coding hSMP-1 was isolated from a human testis cDNA expression library and assigned the accession number U12978. The cDNA was conjugated to a prokaryotic expression vector to construct the recombinant vector, pRSET-HSD-I, which was expressed in Escherichia coli. The recombinant hSMP-1 was isolated and used to immunize rabbits to raise polyclonal antibodies. Usingan immunocytochemical technique, hSMP-1 protein was immunolocalized in germ cells of human testis at all stages of spermatogenesis. mRNAs were prepared from 16 different human tissues and analyzed by Northern blot using HSD-1 as probe. A positive reaction was elicited only with testis mRNA. The present findings suggest that the expression of hSMP-1 gene is testis-specific and occurs during the early stages of germ cell differentiation. In a comparative study, the location of the hSMP-I protein in sperm and in germ cells of the seminiferous tubules of rats was determined. The target antigen was immunolocated on the head and tail of rat sperm and in late spermatids and spermatozoa of rat testis. These results suggest that, in the rat, the HSD-1 gene is expressed during spermiogenesis.

Immune responses in rats following oral immunization with attenuated Salmonella typhimurium expressing human sperm antigen.

The HSD-I gene codes a human sperm membrane protein (hSMP-1) and has been assigned the accession number U12978. The gene is located on human chromosome 9, region p12-p13. When the 1.7-kb cDNA of HSD-I was digested sequentially with EcoRI, BamHI, and HindIII, a 550-bp cDNA fragment was formed, which codes for the extracellular domain. This fragment was cloned into the asd+ vector pYA3149 to construct pYA3149R. The recombinant plasmid was used to transform an avirulent deltacva, deltacrp, deltaasd vaccine strain of Salmonella typhimurium chi4550. The hSMP-1 component was localized on the surface of the head of mature rat spermatozoa by an immunofluorescence technique using polyclonal anti-hSMP-1 antibodies. Since rat sperm contain hSMP-1, this rodent can be used to assay the immunogenicity of pYA3149R. Female Wistar rats were immunized by oral administration of the recombinant Salmonella. Anti-hSMP-1 antibodies in blood and vaginal washes of immunized animals were determined. Both body fluids contained significant amounts of the antibodies, showing that the recombinant Salmonella is an effective oral immunogen in rats.

[Cloning and expression of the detoxifying gene in cyanobacteria].

Plasmid pRL-B1 was constructed from detoxifying gene(called B1) of pesticide resistant Culex and from plasmid pRL-439 containing the strong promoter PpsbA. E. coli-cyanobacteria shuttle expression plasmid pDC-B1 was constructed from shuttle vector pDC-8 and from recombinant plasmid pRL-B1, then it was transferred into Synechococcus sp. PCC7942 by triparental conjugative transfer. The existence of B1 was detected by Southern analysis, and the expression of B1 was confirmed by enzyme activity analysis of detoxification of transgenic cyanobacteria. Experimental results indicated that the transgenic cyanobacteria could degrade beta-naphthyl acetate(beta-NA), a specific substrate of esterase. The enzyme activity of transgenic strain was higher than that of the wild type. It may be the first report on transformation of detoxify gene of pesticide resistant culex into Synechococcus strain.

Identification of gamma-aminobutyric acid transporter (GAT1) on the rat sperm.

Some recent studies indicated that GABAergic system is involved in mammalian sperm acrosome reaction (AR), but direct evidence pertaining to the expression of gat1 in mammalian sperm is not yet demonstrated. In this study, we evaluated the presence of 67kDa GAT1 protein and mRNA in rat testis by Western blotting and reverse transcription-polymerase chain reaction. Meanwhile, immunohistochemical and immunofluorescent analyses also identified GAT1 protein on the elongated spermatid and sperm. These results indicated that rat testis is a novel site of gat1 expression. Further studies should be taken to explore the role of GAT1 protein on sperm acrosome reaction.

Modulation of the Ca(2+)-activated Cl(-) channel by 14-3-3epsilon.

We have previously reported an association of 14-3-3epsilon isoform with calmodulin. Using the voltage-clamp technique, the present study investigated the potential role of 14-3-3 in modulating the Ca(2+)-activated Cl(-) channel (CaCC) endogenously expressed in Xenopus oocytes. Injection of 14-3-3epsilon antisense oligodeoxynucleotides resulted in potentiation of the ionomycin-induced Cl(-) current, while 14-3-3 peptide and calmodulin inhibitor, W13, suppressed the antisense-potentiated current. The data suggest that 14-3-3epsilon plays an inhibitory role in modulating the CaCC by interacting with the calmodulin-dependent pathway. The potential role of 14-3-3epsilon in other tissues and its therapeutic potential for cystic fibrosis are discussed.

The developmental fate of green fluorescent mouse embryonic germ cells in chimeric embryos.

Primordial germ cells (PGCs), as precursors of mammalian germ lineage, have been gaining more attention as a new resource of pluripotent stem cells, which bring a great possibility to study developmental events of germ cell in vitro and at animal level. EG4 cells derived from 10.5 days post coitum (dpc) PGCs of 129/svJ strain mouse were established and maintained in an undifferentiated state. With an attempt to study the differentiation capability of EG4 cells with a reporter protein: green fluorescence protein, and the possible application of EG4 cells in the research of germ cell development, we have generated several EG4-GFP cell lines expressing enhanced green fluorescence protein (EGFP) and still maintaining typical characteristics of pluripotent stem cells. Then, the differentiation of EG4-GFP cells in vitro as well as their developmental fate in chimeric embryos which were produced by aggregating EG4-GFP cells to 8-cell stage embryos were studied. The results showed that EG4 cells carrying green fluorescence have a potential use in the research of germ cell development and other related studies.