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Biomedical subjects

Jun Wang

Publications and source records attributed to Jun Wang.

At least 325 records · Page 18Linked to original sources
PubMed2005

[Experimental study on the DNA damage of NIH/3T3 cells induced by nickel-refining dusts].

OBJECTIVE: To study the effects of nickel-refining dusts on DNA damage in mouse NIH/3T3 cell. METHOD: DNA damage of mouse NIH/3T3 cell induced by two nickel-refining dust samples was determined with single cell gel electrophoresis (SCGE) technique. RESULTS: (1) Under the condition of the same treatment time, the tailed cell (%) of NIH/3T3 cells increased with the increase in doses of nickel-refining dusts (35.5%, 69.7%, 85.2%, 41.3%, 75.7%, 89.2% respectively except for sample 2, 50 microg/ml, 24 h group), and DNA strand breaks reached the peak value at 4 h of exposure; (2) When we treated the NIH/3T3 cells with the same dose of nickel-refining dusts, the tail rate at 4 h was higher than those at 2 h and 24 h of exposure; (3) Both sample 1 and sample 2 with different doses of nickel-refining dusts could induce higher comet tail, DNA%, tail length (except for 12.5 microg/ml), extent of TM (except for sample 1, 12.5 microg/ml) than in control group (P < 0.05). The DNA damage range was significantly increased in different tested doses of nickel-refining dusts and the damage range reached the peak value when the cells were treated for 4 h. CONCLUSION: Nickel-refining dusts could induce different degree DNA damage in NIH/3T3 cells.

Animals↗
PubMed2005

Enhanced induction of prostatic dysplasia and carcinoma in Noble rat model by combination of neonatal estrogen exposure and hormonal treatments at adulthood.

Estrogens have been implicated to play certain but yet undefined roles in the normal and neoplastic growth of prostate gland. Studies of perinatal exposure in rodents demonstrate that effects of perinatal estrogenization are permanent and carcinogenic in prostate gland. In the Noble (Nb) rat model, prostatic dysplasia and neoplastic lesions can be induced by a chronic treatment with both testosterone and estrogen at adulthood. However, by this conventional protocol, neoplastic lesions are mostly confined to the lateral (LP) and ventral (VP) prostates, while gross prostatic tumors are rarely induced. Based on these two experimental models, we developed a modified treatment protocol for the enhancement of prostate cancer induction in Nb rat model by combining neonatal estrogen exposure of male offspring followed by the hormonal treatment at adulthood (NeoE + T-E2). Using this modified protocol, we were able to induce more extensive development of neoplastic lesions in all three prostatic lobes and also gross tumors at relatively high incidence within 6-9 months. Western blottings and immunohistochemistry showed that ERalpha expression was increased in the hypertrophic peri-acinar and -ductal smooth muscle cells while ERbeta and AR expressions are markedly decreased in dysplastic and neoplastic lesions in NeoE + T-E2-treated prostates. Immunohistochemistry showed that expression of three tumor suppressors (BRCA2, PTEN, and Rap1) and tubulin-alpha are markedly decreased in dysplastic and neoplastic lesions. In addition, loss of expression of smooth muscle differentiation markers (desmin, alpha-actin, and vinculin) and defects of basement membranes were also seen in the reactive stroma. These results suggest that exposure to high levels of estrogens, either endogenous or exogenous, in early life could play a role in the development of prostate cancer in later life.

Actins↗
PubMed2005

Degradation of dyestuff wastewater using visible light in the presence of a novel nano TiO2 catalyst doped with upconversion luminescence agent.

A new upconversion luminescence agent, 40CdF2 x 60BaF2 x 0.8Er2O3, was synthesized and its fluorescent spectra were determined. This upconversion luminescence agent can emit five upconversion fluorescent peaks shown in the fluorescent spectra whose wavelengths are all below 387 nm under the excitation of 488 nm visible light. This upconversion luminescence agent was mixed into nano rutile TiO2 powder by ultrasonic and boiling dispersion and the novel doped nano TiO2 photocatalyst utilizing visible light was firstly prepared. The doped TiO2 powder was charactered by XRD and TEM and its photocatalytic activity was tested through the photocatalytic degradation of methyl orange as a model compound under the visible light irradiation emitted by six three basic color lamps. In order to compare the photocatalytic activities, the same experiment was carried out for undoped TiO2 powder. The degradation ratio of methyl orange in the presence of doped nano TiO2 powder reached 32.5% under visible light irradiation at 20 h which was obviously higher than the corresponding 1.64% in the presence of undoped nano TiO2 powder, which indicate the upconversion luminescence agent prepared as dopant can effectively turn visible lights to ultraviolet lights that are absorbed by nano TiO2 particles to produce the electron-cavity pairs. All the results show that the nano rutile TiO2 powder doped with upconversion luminescence agent is a promising photocatalyst using sunlight for treating the industry dye wastewater in great force.

Azo Compounds↗
PubMed2005

Persistent organochlorine residues in sediments of Haihe River and Dagu Drainage River in Tianjin, China.

Persistent organochlorine compounds were analyzed by means of GC-ECD in surface sediment samples from two selected rivers in Tianjin, Haihe River and Dagu Drainage River. A total of 16 surface sediment sites were selected along the both rivers. The frequency of detection of T-HCH and T-DDT in sediment samples both was up to 100%, which illustrated that the contamination of HCH and DDT was widespread in Haihe and Dagu Drainage Rivers. Results indicated that the concentrations of various pesticides in sediments from Haihe River were in the range of 3.30-75.96 ng/g dw for T-HCH and 1.57-211.57 ng/g dw for T-DDT. Compared with Haihe River, Dagu Drainage River was contaminated by HCHs and DDTs along the all locations and the values of T-HCH and T-DDT residues in sediments ranged from 2.30 to 124.61 ng/g dw and from 11.28 to 237.30 ng/g dw, respectively. The possible pollution sources were analyzed through monitoring results of organochlorine pesticides(OCPs) residues in sediments from the two rivers. The investigation also indicated that HCH was still used as pesticide in Tianjin partial area.

China↗
PubMed2005

[Purging effects of CD3AK/iNOS in vitro on primary leukemic cells from chronic myeloid leukemia patients].

To investigate the purging effect of CD3AK/iNOS on primary leukemic cells from chronic myeloid leukemia patients in vitro, amphotropic packaging cell line PA317 transfected with the whole length of iNOS gene was cultivated, amplified and screened by G418. The viral titer was determined by the NIH3T3 cells. Human peripheral blood mononuclear cells were isolated and activated by anti-CD3 monoclonal antibody in vitro. CD3AK cells were incubated with viral supernatant and selected by G418. Resistant clones were assayed for iNOS gene expression by RT-RCR. The content of nitric oxide and the activity of iNOS in the culture supernatant of CD3AK/iNOS were evaluated by the method of Griess. After BMMNC or PBMNC from CML patients were co-cultured with CD3AK/iNOS, CD3AK/Neo and CD3AK/iNOS respectively, the expression of bcr/abl fusion gene was detected by serial dilution semi-quantitative net RT-PCR assay. The results showed that anti-G418 positive packaging cell line PA317 transfected with the whole length of iNOS gene clones could stably synthesize and excrete recombinant retroviral vectors. The titer of recombinant retroviral vectors was 1.0 x 10(5) CFU/ml. After being transfected by recombinant retroviral supernatant, the iNOS cDNA was expressed in CD3AK/iNOS. The content of NO and activity of iNOS that synthesized and excreted by CD3AK/iNOS were notably increased, compared with those of CD3AK. There were statistically significant differences in NO content and iNOS activity between two groups. After BMMNC or PBMNC from CML patients were co-cultured with CD3AK/iNOS, CD3AK/Neo and CD3AK/iNOS respectively, the expression of bcr/abl fusion gene in all of them was down-regulated by serial dilution semi-quantitative RT-PCR assay. It is concluded that construction of CD3AK/iNOS can markedly increase the content of NO and the activity of iNOS, which can be more efficient in in vitro purging leukemia cells for autologous hematopoietic stem cell transplantation.

Adult↗
PubMed2005

[Induction of immune tolerance for allogenic recipient mice by non-myeloablative bone marrow transplantation].

This study was aimed to explore the effects and mechanisms of transplantation tolerance induced by "TBI + cyclophosphamide (CTX)" regimen combined with intra-bone marrow injection of allogenic BMCs. On day 0 C57BL/6 (H-2(b), B6) mice received sublethal dose of total body irradiation (TBI) ((60)Co gamma-ray) followed by intrabone marrow-bone marrow transplantation (IBM-BMT) of 3 x 10(7) cells/30 microl BMCs from BALB/c (H-2(d)) mice. The recipient mice were given CTX intraperitoneally 2 days after IBM-BMT. On day 7 skin grafting was performed and the skin survival was observed. The tolerance mechanism was investigated by mixed lymphocyte reaction (MLR), IL-2 reverse test, adoptive transfer assay in vitro. The results showed that the mean survival time (MST) of skin allografts in group treated with TBI + CTX + BMT was significantly longer, compared with that of other groups (P < 0.01). On day 90 after IBM-BMT, the phenotypic character of the recipient mice (black color) began to convert to that of the donor mice (white color). The MLR demonstrated that the immune responses of recipient mice were donor-specific tolerance. Suppressive activity in the spleen cells of tolerant B6 mice was observed in adoptive transfer assay in vitro. IL-2 reversal and the phenotypic conversion showed that the tolerance mechanisms were involved in clonal anergy and the development of chimerism. It is concluded that the nonmyeloablative regimen combined with IBM-BMT can induce a long-term tolerance, and the multiple mechanisms including clonal anergy, suppressor cells and chimerism were involved in transplantation immune tolerance.

Animals↗
PubMed2005

[Enzymatic degradation of organophosphorus insecticide chlorpyrifos by fungus WZ-I].

Degradation characteristics of chlorpyrifos insecticides was determined by the crude enzyme extracted from the isolated strain WZ-I ( Fusarium LK. ex Fx). The best separating condition and the degrading characteristic of chlorpyrifos were studied. Rate of degradation for chlorpyrifos by its intracellular enzyme, extracellular enzyme and cell fragment was 60.8%, 11.3% and 48%, respectively. The degrading enzyme was extracted after this fungus was incubated for 8 generations in the condition of noninducement, and its enzymic activity lost less, the results show that this enzyme is an intracellular and connatural enzyme. The solubility protein of the crude enzyme was determined with Albumin (bovine serum) as standard protein and the solubility protein of the crude enzyme was 3.36 mg x mL(-1). The pH optimum for crude enzyme was 6.8 for enzymatic degradation of chlorpyrifos, and it had comparatively high activity in the range of pH 6.0 - 9.0. The optimum temperature for enzymatic activity was at 40 degrees C, it still had comparatively high activity in the range of temperature 20-50 degrees C, the activity of enzyme rapidly reduced at 55 degrees C, its activity was 41% of the maximal activity. The crude enzyme showed Km value for chlorpyrifos of 1.049 26 mmol x L(-1), and the maximal enzymatic degradation rate was 0.253 5 micromol x (mg x min)(-1). Additional experimental evidence suggests that the enzyme had the stability of endure for temperature and pH, the crude enzyme of fungus WZ-I could effectively degrade chlorpyrifos.

Biodegradation, Environmental↗
PubMed2005

[A study on the sero-epidemiology of hepatitis B in Chinese population aged over 3-years old].

OBJECTIVE: To better understand and measure the impact from immunization activities over the last 10-years, we conducted a sero-epidemiological study using the remaining blood samples of a nationwide survey on Nutrition and Health in Chinese residents, in 2002. METHODS: HBsAg, anti-HBs and anti-HBc in blood samples were tested using enzyme-linked immunosorbent assay(ELISA) reagents and revised by solid phase radioimmunoassay and Abbott ELISA reagents. RESULTS: Among population older than 3 years, the prevalence rates of HBsAg, anti-HBs and hepatitis B virus(HBV) infection were 9.09%, 37.48% and 50.04% but for children between 3 and 12 year olds, they were 5.03%, 45.33% and 29.10% respectively. Among population older than 3 years, the rates of HBsAg and HBV infection in urban area were 4.61% and 43.51%, but the rates in rural area were 9.41% and 56.77% respectively while for children from 3-years to 12-years old, they rates were 2.10%, 20.45% in urban area and 8.25%, 39.22% in rural areas, respectively. CONCLUSION: Results revealed that since the hepatitis B vaccine was introduced into the expanded program on immunization(EPI) from 1992, the prevalence rates of HBsAg and HBV infection, especially in the children from 3 to 12 years of age, had obviously declined, suggesting that some changes had happened in the epidemic characters of hepatitis B in China.

Adolescent↗
PubMed2005

[Study on a monitoring program regarding leptospirosis in some fore-and-after flood-affected along large rivers in Anhui province].

OBJECTIVE: The study was designed to find out the epidemic characteristics of leptospriosis and to develop effective intervention measures. The effects of floods on leptospriosis in some areas along Yangzi river and Huai river in Anhui province was also analysed. METHODS: Study on serum epidemiology of leptospriosis was carried out from serous samples collected from native residents and animal hosts including isolation of pathogens at different phases (before,middle and after) and different monitoring spots,during the floods. RESULTS: Infection rate with leptospriosis pathogen among native residents was 13.49% during the flood-period,much higher than 2.18% at post-flood (chi2 = 22.78, P < 0.01) stage, in the flood-affected areas along Yangzi river in 1998. The average rates of infection were 2.48% and 5.35% in affected and unaffected areas along Huai river respectively, in 2003. CONCLUSIONS: There was full evidence that floods causing the epidemics of leptospriosis. However, the transmission of leptospriosis among people would depend on affecting factors as scales of floods, lasting time, coincidence between flood happening and epidemic season, immuno-protection level against leptospriosis among people and so on to a great extent. Factors as the magnitude of pathogens carried by various kinds of infectious sources were also important determinants affecting the nature, being epidemic or pandemic of leptospriosis. It was suggested that active surveillance network on the sources of infection and risk factors of leptospriosis should be developed for the control and prevention of the disease, in the flood-hit areas.

Adolescent↗
PubMed2005

[Application of microdebritor in the treatment of the juvenile onset recurrent respiratory papillomatosis].

OBJECTIVE: To evaluate the treatment methods and improve the curative effects of the juvenile onset recurrent respiratory papillomatosis. METHOD: Fourteen patients with juvenile onset recurrent respiratory papillomatosis were treated from 2002 to 2003 by using microdebritor. RESULT: Among the 14 cases, eight cases had no recurrence after three to six operations within six month follow up and were decannulated,the other six cases had recurrence postoperatively. CONCLUSION: It is demonstrated that microdebritor surgery is an ideal therapy for the treatment of juvenile onset recurrent respiratory papillomatosis.

Child↗
PubMed2004

Cloning and characterization of a novel human zinc finger gene, hKid3, from a C2H2-ZNF enriched human embryonic cDNA library.

To investigate the zinc finger genes involved in human embryonic development, we constructed a C(2)H(2)-ZNF enriched human embryonic cDNA library, from which a novel human gene named hKid3 was identified. The hKid3 cDNA encodes a 554 amino acid protein with an amino-terminal KRAB domain and 11 carboxyl-terminal C(2)H(2) zinc finger motifs. Northern blot analysis indicates that two hKid3 transcripts of 6 and 8.5kb express in human fetal brain and kidney. The 6kb transcript can also be detected in human adult brain, heart, and skeletal muscle while the 8.5kb transcript appears to be embryo-specific. GFP-fused hKid3 protein is localized to nuclei and the ZF domain is necessary and sufficient for nuclear localization. To explore the DNA-binding specificity of hKid3, an oligonucleotide library was selected by GST fusion protein of hKid3 ZF domain, and the consensus core sequence 5'-CCAC-3' was evaluated by competitive electrophoretic mobility shift assay. Moreover, The KRAB domain of hKid3 exhibits transcription repressor activity when tested in GAL4 fusion protein assay. These results indicate that hKid3 may function as a transcription repressor with regulated expression pattern during human development of brain and kidney.

Animals↗
PubMed2004

ZNF322, a novel human C2H2 Kruppel-like zinc-finger protein, regulates transcriptional activation in MAPK signaling pathways.

Cardiac differentiation involves a cascade of coordinated gene expression that regulates cell proliferation and matrix protein formation in a defined temporal-spatial manner. The C(2)H(2) zinc finger-containing transcription factors have been implicated as critical regulators of multiple cardiac-expressed genes and are important for human heart development and diseases. Here we have identified and characterized a novel zinc-finger gene named ZNF322 using degenerated primers from a human embryo heart cDNA library. The gene contains four exons and spans 23.2kb in chromosome 6p22.1 region, and transcribes a 2.7kb mRNA that encodes a protein with 402 amino acid residues. The predicted protein contains 9 tandem C(2)H(2)-type zinc-finger motifs. Northern blot analysis shows that ZNF322 is expressed in every human tissue examined at adult stage and during embryonic developmental stages from 80 days to 24 weeks. When overexpressed in COS-7 cells, ZNF322-EGFP fusion protein is detected in the nucleus and cytoplasm. Reporter gene assays show that ZNF322 is a transcriptional activator. Furthermore, overexpression of ZNF322 in COS-7 cells activates the transcriptional activity of SRE and AP-1. Together, these results suggest that ZNF322 is a member of the zinc-finger transcription factor family and may act as a positive regulator in gene transcription mediated by the MAPK signaling pathways.

Amino Acid Sequence↗
PubMed2004

A draft sequence for the genome of the domesticated silkworm (Bombyx mori).

We report a draft sequence for the genome of the domesticated silkworm (Bombyx mori), covering 90.9% of all known silkworm genes. Our estimated gene count is 18,510, which exceeds the 13,379 genes reported for Drosophila melanogaster. Comparative analyses to fruitfly, mosquito, spider, and butterfly reveal both similarities and differences in gene content.

Algorithms↗
PubMed2004

A genetic variation map for chicken with 2.8 million single-nucleotide polymorphisms.

We describe a genetic variation map for the chicken genome containing 2.8 million single-nucleotide polymorphisms (SNPs). This map is based on a comparison of the sequences of three domestic chicken breeds (a broiler, a layer and a Chinese silkie) with that of their wild ancestor, red jungle fowl. Subsequent experiments indicate that at least 90% of the variant sites are true SNPs, and at least 70% are common SNPs that segregate in many domestic breeds. Mean nucleotide diversity is about five SNPs per kilobase for almost every possible comparison between red jungle fowl and domestic lines, between two different domestic lines, and within domestic lines--in contrast to the notion that domestic animals are highly inbred relative to their wild ancestors. In fact, most of the SNPs originated before domestication, and there is little evidence of selective sweeps for adaptive alleles on length scales greater than 100 kilobases.

Alleles↗
PubMed2004

The analysis of large-scale gene expression correlated to the phase changes of the migratory locust.

The migratory locust is one of the most notorious agricultural pests that undergo a well known reversible, density-dependent phase transition from the solitary to the gregarious. To demonstrate the underlying molecular mechanisms of the phase change, we generated 76,012 ESTs from the whole body and dissected organs in the two phases. Comparing 12,161 unigene clusters, we identified 532 genes as phase-related (P < 0.01). Comprehensive assessment of the phase-related expression revealed that, whereas most of the genes in various categories from hind legs and the midgut are down-regulated in the gregarious phase, several gene classes in the head are impressively up-regulated, including those with peptidase, receptor, and oxygen-binding activities and those related to development, cell growth, and responses to external stimuli. Among them, a superfamily of proteins, the JHPH super-family, which includes juvenile hormone-binding protein, hexamerins, prophenoloxidase, and hemocyanins, were highly expressed in the heads of the gregarious hoppers and hind legs of the solitary hoppers. Quantitative PCR experiments confirmed in part the EST results. These differentially regulated genes have strong functional implications that numerous molecular activities are involved in phase plasticity. This study provides ample molecular markers and genomic information on hemimetabolous insects and insights into the genetic and molecular mechanisms of phase changes in locusts.

Animals↗
PubMed2004

Development of miniaturized competitive immunoassays on a protein chip as a screening tool for drugs.

BACKGROUND: Doping in sports has become a serious problem. Gas chromatography-mass spectrometry (GC-MS) serves as an effective reference method, but it is limited by low throughput and is therefore not suitable for large-scale screening. Use of protein chips for high-throughput screening of all athletes for prohibited substances could become an important complementary tool to GC-MS. METHODS: We developed a protein chip based on an aldehyde-activated glass slide containing 10 physically isolated arrays. The chip was used to screen urine from 1347 athletes for prohibited substances and to screen a negative control group consisting of 200 females and 120 males. Urine samples from 66 individuals known to be abusers, provided by the China Doping Control Center (CDCC), and 129 standard prohibited substances were tested as positive controls. RESULTS: All 1347 urine samples screened by means of the protein chips were also subjected to reference analysis by GC-MS at the CDCC. There was no qualitative difference between the results obtained with the two methods. The correlation coefficient (r(2)) for the quantitative results obtained with the protein chip and GC-MS was 0.991. CONCLUSIONS: The protein chip could be used to screen for a series of 16 prohibited drugs in urine samples. This system has the potential to become an effective screening method to test substances prohibited by the International Olympic Committee.

Doping in Sports↗
PubMed2004

Single mucosal, but not parenteral, immunization with recombinant adenoviral-based vaccine provides potent protection from pulmonary tuberculosis.

Bacillus Calmette-Guerin (BCG) vaccine has failed to control the global tuberculosis (TB) epidemic, and there is a lack of safe and effective mucosal vaccines capable of potent protection against pulmonary TB. A recombinant replication-deficient adenoviral-based vaccine expressing an immunogenic Mycobacterium tuberculosis Ag Ag85A (AdAg85A) was engineered and evaluated for its potential to be used as a respiratory mucosal TB vaccine in a murine model of pulmonary TB. A single intranasal, but not i.m., immunization with AdAg85A provided potent protection against airway Mycobacterium tuberculosis challenge at an improved level over that by cutaneous BCG vaccination. Systemic priming with an Ag85A DNA vaccine and mucosal boosting with AdAg85A conferred a further enhanced immune protection which was remarkably better than BCG vaccination. Such superior protection triggered by AdAg85 mucosal immunization was correlated with much greater retention of Ag-specific T cells, particularly CD4 T cells, in the lung and was shown to be mediated by both CD4 and CD8 T cells. Thus, adenoviral TB vaccine represents a promising novel vaccine platform capable of potent mucosal immune protection against TB. Our study also lends strong evidence that respiratory mucosal vaccination is critically advantageous over systemic routes of vaccination against TB.

Acyltransferases↗