Biomedical subjects

J Hou

Publications and source records attributed to J Hou.

At least 37 records · Page 2Linked to original sources

PubMed2001

Novel HLA-B alleles identified in potential marrow donors: B3917, B1405 and B*3528.

Sequence-specific oligonucleotide probe hybridization and sequence-specific primer polymerase chain reaction (PCR) typing of volunteer bone marrow donors suggested the presence of variants of known HLA-B alleles in five individuals. PCR products encompassing HLA-B locus exons 1 through 3 were prepared and subcloned. Three African-American individuals had a novel HLA-B*39 allele (B*3917), and another African-American was found to have a novel HLA-B*14 allele (B*1405). In a third individual of Hispanic origin, a novel HLA-B*35 allele (B*3528) was identified. These findings further illustrate the substantial genetic variation present at the HLA-B locus within human populations.

Alleles↗

PubMed2001

Prevalence of naturally occurring surface gene variants of hepatitis B virus in nonimmunized surface antigen-negative Chinese carriers.

Previous studies have suggested that hepatitis B virus (HBV) variants may account for the presence of HBV DNA in hepatitis B surface antigen (HBsAg)-negative patients (occult HBV infection). However, it is not known how widespread these variants are and how they influence the course of liver disease. To determine the prevalence of variants within the major hydrophilic region (MHR) of HBsAg, we investigated 2,565 subjects, including subjects with chronic hepatitis, cryptogenic cirrhosis, hemodialysis patients, and blood donors. Fifty-one of them had occult HBV infection. The entire S gene from 46 of these patients was sequenced from amplified serum HBV DNA. Forty-three percent (20 of 46) had mutations in the MHR of HBsAg. Thirty-two amino acid substitutions between positions 100-160 of the MHR of HBsAg were detected in 18 patients, and these ranged from 1 to 4 per patient. These changes involved 11 positions inside and 5 outside of the historical first and second loops of the "a" determinant, and included the following: Q101K, T115A, K122N, T123A, T126N, Q129N, G130R, T131I, M133T, F134L, C138Y, K141E, P142S, G145R, N146S, and C147F/R. Combinations of mutations were detected in 9 patients, and 7 of these have not been described before. Two further patients had insertion mutations immediately before the "a" determinant. Monoclonal antibody binding tests with the Royal Free hepatitis B surface (RFHBs) panel of antibodies revealed decreased immunoreactivity in 6 novel variants of HBsAg. The existence of patients with occult HBV infection caused by HBsAg variants, therefore, has implications for their possible transmission through sexual contact and by blood transfusion.

Alanine Transaminase↗

PubMed2001

Concordant p53 and mdm-2 protein expression in vulvar squamous cell carcinoma and adjacent lichen sclerosus.

To determine if carcinogenic events in vulvar skin precede the onset of morphologic atypia, the authors investigated for derangements in DNA content, cell proliferation, and cell death in vulvar carcinomas and surrounding skin in 140 samples of tumor and surrounding skin collected from 35 consecutive vulvectomy specimen for squamous cell carcinoma (SCC) or vulvar intraepithelial neoplasia (VIN) 3. Vulvar non-cancer excisions were used as controls. Investigations consisted of histologic classification and measurement of 9 variables--epidermal thickness (acanthosis and rete ridge length), immunolabeling index (LI) for 3 proteins (p53 protein, Ki-67, and mdm-2), pattern of p53 expression (dispersed vs. compact), DNA content index, and presence of aneuploidy by image analysis and apoptotic rate by Apotag labeling. Significant positive correlations were found for all nine variables studied versus increasing histologic severity in two proposed histologic stepwise models of vulvar carcinogenesis (lichen sclerosus (LS) and VIN 3 undifferentiated associated SCC groups). High p53 LI (>25) and the compact pattern of p53 expression (suspected oncoprotein) significantly correlated with LS and its associated vulvar samples compared with samples not associated with LS (P < or = 0.001). Furthermore, p53 LI, mdm-2 LI, and pattern of p53 expression were concordant between patient matched samples of LS and SCC. In addition, mdm-2 LI significantly correlated with dispersed pattern p53 LI suggesting a response to wild-type p53 protein accumulation. These findings support the hypothesis that neoplastic transformation occurs in sequential steps and compromises proteins involved in the cell cycle control. Concordance of p53 and mdm-2 protein expression in LS and adjacent SCC provides evidence that LS can act as a precursor lesion in the absence of morphologic atypia. Overexpression of mdm-2 with stabilization and inactivation of p53 protein may provide an alternate pathway for vulvar carcinogenesis.

Adult↗

PubMed2001

Inhibition of p38 MAPK alpha/beta reduces ischemic injury and does not block protective effects of preconditioning.

We examined the effect of inhibition of p38 mitogen-activated protein kinase (MAPK) alpha/beta during ischemia and preconditioning by using the inhibitor SB-202190. Isolated rat hearts were perfused with Krebs-Henseleit buffer, while left ventricular developed pressure (LVDP) and (31)P nuclear magnetic resonance spectra were acquired continuously. After 20 min of ischemia and 25 min of reperfusion, recovery of LVDP in untreated hearts was 32 +/- 4%, whereas hearts treated with SB-202190 5 min before ischemia recovered 59 +/- 7% of their pretreatment LVDP. Preconditioning improved functional recovery to 65 +/- 5%, which was unaffected by SB-202190 treatment, added either throughout the preconditioning protocol (56 +/- 5% recovery) or during the final reperfusion period of preconditioning (71 +/- 11% recovery). Necrosis was assessed after 40 min of ischemia and 2 h of reperfusion using 2,3,5-triphenyltetrazolium chloride (TTC) staining and creatine kinase release. The untreated group had 54 +/- 8% necrotic myocardium, whereas the SB-202190-treated group had 32 +/- 7% and the preconditioned group had 21 +/- 4% necrotic tissue by TTC staining.

Animals↗

PubMed2001

A randomized trial of augmented prenatal care for multiple-risk, Medicaid-eligible African American women.

OBJECTIVES: This project investigated whether augmented prenatal care for high-risk African American women would improve pregnancy outcomes and patients' knowledge of risks, satisfaction with care, and behavior. METHODS: The women enrolled were African American, were eligible for Medicaid, had scored 10 or higher on a risk assessment scale, were 16 years or older, and had no major medical complications. They were randomly assigned to augmented care (n = 318) or usual care (n = 301). Augmented care included educationally oriented peer groups, additional appointments, extended time with clinicians, and other supports. RESULTS: Women in augmented care rated their care as more helpful, knew more about their risk conditions, and spent more time with their nurse-providers than did women in usual care. More smokers in augmented care quit smoking. Pregnancy outcomes did not differ significantly between the groups; however, among patients in augmented care, rates of preterm births were lower and cesarean deliveries and stays in neonatal intensive care units occurred in smaller proportions. Both groups had lower-than-predicted rates of low birthweight. CONCLUSIONS: High-quality prenatal care, emphasizing education, health promotion, and social support, significantly increased women's satisfaction, knowledge of risk conditions, and perceived mastery in their lives, but it did not reduce low birthweight.

Adolescent↗

PubMed2001

Genetic mutations of precore region of hepatitis B virus in hepatitis B e antigen-negative patients with fulminant hepatitis B and translation of precore variants in vitro.

OBJECTIVE: To detect mutations in precore region of hepatitis B virus of HBeAg negative- patients with fulminant hepatitis and to determine the effect of T1862 mutants on synthesis of precursor of hepatitis B e antigen. METHODS: The entire precore and core region were amplified from sera of nine HBeAg negative-patients with fulminant hepatitis B by polymerase chain reaction (PCR). PCR products were cloned into plasmid pUC18, and sequencing for analysis of precore mutations. Precore and core sequence of T1862 variant were also cloned into expression plasmid pGEMT for in vitro transcription and translation study on synthesis and procession of e antigen. RESULTS: Three variants, A1896, A1899 and T1862, whose nucleotide mutation led to amino acids substitutions, were detected in patients with fulminant hepatitis. T1862 variant didn't effect the synthesis of precursor of e antigen. Also there was no variant detected in precore region of hepatitis B virus in two patients. CONCLUSIONS: The causes for negative of e antigen in fulminant hepatitis patients may be partially explained by precore mutation of A1896 and T1862, and the latter variant may effect the process of precursor of e antigen, rather than the synthesis of precursor protein.

Base Sequence↗

PubMed2001

[Genotype polymorphism and its implications of mannose-binding protein allele in 5 Chinese nationalities].

OBJECTIVE: To detect the genotypes and sequences of the exon 1 of human mannose-binding protein (MBP) allele in 5 Chinese nationalities. METHODS: The genotypes of MBP gene of 5 Chinese nationalities were detected by polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP). The exon 1 of the MBP gene of 22 Chinese Hans was analyzed by using ABI 310 genetic analyzer. RESULTS: The DNA sequences of exon 1 of Chinese MBP gene were acquired. The allele frequencies of the codon 54 of the MBP gene (MBP-54) of 5 Chinese nationalities were 0.181(Hans), 0.128(Uygurs), 0.181(Mongols), 0.179(Tibetans) and 0.181(Yis). The allele distribution for MBP-54 mutation of 5 Chinese nationalities was in good agreement with Hardy-Weinberg equilibrium. Compared with the Hans, Uygurs had a lower MBP-54 mutation rate. There were no differences in the allele frequencies between the chronic hepatitis B patients and health controls in Chinese Hans. The mutations of the codons 52 and 57 were not detected in this study. CONCLUSION: A higher prevalence of MBP-54 mutation was found in 5 Chinese nationalities, MBP-54 mutation was not associated with the persistence of hepatitis B.

Adolescent↗

PubMed2001

[High expression of rabbit sperm membrane protein rSP10 in Escherichia coli and preparation of its specific antisera].

To study the position and immunogenicity of rSP10, the rabbit rsp10 gene which did not include sequences coding for signal peptides was inserted into expression vector pET30a. An in-frame fusion protein was made such that a His6 stretch was produced at the N terminus of re-rSP10. High expression was obtained, the amount of re-rSP10 up to 67% in the total bacterial protein. The re-rSP10 was purified by DEAE chromatography and the yield of purified re-rSP10 was approximately 50 micrograms/mL of culture. Western blotting analysis of re-rSP10 with rabbit polyclonal sera raised against rabbit sperm membrane protein showed that the synthesized antigen possessed immunogenicity of rSP10. Specific antisera against re-rSP10 was induced using purified re-rSP10 as an antigen. The motility of capacitated sperms were affected but no aggregation was observed.

Animals↗

PubMed2001

[Purification feasibility of malodorous waste gas contained H2S and CS2 by DBD technique].

Dielectric barrier discharge(DBD) technique was applied to remove H2S and CS2 in industrial waste gas. In the research of laboratory, when the voltage between two electrodes was 12 kV, 4 x 10(3) Pa H2S was discharged in air for 5 seconds, about 100% of H2S was transformed into H2O and SO2; 1.33 x 10(3) Pa CS2 was discharged in air for 15 seconds, about 80% of CS2 was transformed into CO2, CO and SO2. When the concentration of H2S and CS2 increased, the decomposition of them decreased. Based on the results, a DBD purification apparatus which can dispose 420 m3/h, 10 m/s waste gas was designed and manufactured, the removal rate of H2S can reach 89% and the energy consumption was 5.2 W.h/m3. It was concluded that the DBD technique is worth disposing malodorous industrial waste gases contained H2S and CS2.

Carbon Disulfide↗

PubMed2001

[A preliminary study on translocation of the immunoglobulin heavy chain gene in KM3 myeloma cell line].

OBJECTIVE: To identify the IgH translocation in KM3 myeloma cell line established from a Chinese patients. METHODS: Southern blotting was performed with dig-labeled probes specific for IgH switch regions to identify and distinguish IgH switch recombination events. RESULTS: Besides a 10.0 kb Hind III fragment being able to hybridize with both 5' S mu and 3' S mu probes as that in placenta genome DNA. There was a 5.6 kb Hind III fragment in KM3 genome DNA could only hybridize with the 3' S mu probe. CONCLUSION: There was an illegitimate switch recombination fragment containing 3' S mu region in the KM3 myeloma cell line, which was caused by the IgH translocation involving the IgH S mu region.

Blotting, Southern↗

PubMed2001

Th1/Th2 type cytokines in hepatitis B patients treated with interferon-alpha.

OBJECTIVE: To investigate the relationship between the expression of Th1/Th2 type cytokines and the effect of interferon-alpha therapy. METHODS: Th1/Th2 type cytokines were assayed by enzyme-linked immunosorbent assay (ELISA) and reverse transcription polymerase chain reaction (RT-PCR) on 23 patients with chronic hepatitis B who were treated with interferon-alpha. RESULTS: Levels of IFN-gamma in the supernatant of peripheral blood mononuclear cells (PBMC) cultures from the patients with hepatitis B were slightly lower than those of controls (P = 0.07). However, the levels of IL-4 were higher than those of controls (P = 0.01). Cytokines measurements during IFN-alpha treatment showed a trend to decreasing levels of IL-4 at 4, 12, and 24 weeks. Levels of IFN-gamma were slightly increased following IFN-alpha treatment (P = 0.09). In patients with a complete response to IFN-alpha, the levels of IFN-gamma were higher at 24 weeks following IFN-alpha treatment than that of pre-treatment (P = 0.04), and the levels of IL-4 decreased markedly at 12 and 24 weeks (P = 0.02, 0.03, respectively). mRNA expression positively correlated with the level of Th1/Th2 type cytokines in the supernatant. CONCLUSION: The expression of Th2 type cytokines is predominant in patients with chronic hepatitis B. Interferon-alpha therapy can modulate the balance of Th1/Th2 type cytokines, and this is related to its clinical effect. Levels of Th1/Th2 type cytokines could be a predictor of clinical response during Interferon-alpha treatment.

Antiviral Agents↗

PubMed2001

[Study on structure change and hypermethylation of p16 gene in multiple myeloma].

OBJECTIVE: To illustrate the role of structure and hypermethylation of p16 gene in the pathogenesis of multiple myeloma(MM). METHODS: By using PCR-single strand conformation polymorphisms(PCR-SSCP) and methylation-specific PCR(MSP) techniques, the structure and hypermethylation status of p16 gene in MM cell lines and patients were analysed. RESULTS: Homozygous deletion of p16 exon 2 was found in KM3 cells. The completely methylated p16 gene and hypermethylation of CPG island were observed in U266, LP1 cell lines and 55.56% of MM patients. CONCLUSION: Methylation of p16 gene is important in the pathogenesis of MM and may provide a new drug target for the treatment of MM.

Aged↗

PubMed2001

[Exploration of high expressions of retroviral vectors containing hFIX minigene in murine myoblast cells].

OBJECTIVE: To explore the effect of different vector structure on hF IX protein expression in murine myoblasts in order to construct more efficient expression vector for my oblast-mediated gene therapy for hemophilia B. METHODS: Three types of retroviral vectors pLMe2 IX m(2)SN (forward Me2: Me2 inserted into enhancer region of 3'LTR in forward orientation), pLMe2 IX m(2)SN (reversed Me2) and pL IX m(2)SN which contained intron m(2) and two copies of MCK enhancer (Me2) were transferred into packaging cell line PA317. The hFIX expression level in selected single and mixed clones of stably transfected myoblasts were determined by ELISA and PCR. RESULTS: There was statistically significant difference in hFIX expression levels among the four vectors tested. The expression order was LMe2 IX m(2)SN (forward) > LMe2 IX m(2)SN (reversed) > L IXm(2)SN > L IX SN. The hF IX expression level of forward Me2 vector was higher than that of reversed one, because of one or two copies of reversed Me in the 5'LTR being deleted in the genome of myoblasts, but the orientation of Me or Me2 remained unchanged. CONCLUSIONS: To select a tissue-specific enhancer and optimize FIX minigene construction are effective methods for increasing the expression level. Forward Me2 vector can express hFIX more stably than the reversed one.

Animals↗

PubMed2001

[Antigen sandwiched ELISA for detection of total HIV antibodies].

OBJECTIVE: To establish a sensitive antigen sandwiched ELISA(AS) for detection of the total antibodies to HIV-1/2. METHODS: Based on the gene sequence of HIV-1/2 type and its coded amino acid structure, 5 polypeptides were synthesized as coated antigens using solid-phase method. These polypeptides were labelled with horseradish peroxidase. And the total antibodies of HIV-1/2 were detected with the same method. RESULTS: These reagents were detected by three batches of HIV panel from The National Institute for the Control of Pharmaceutical and Biological Products (NICPBP). The results indicated that the corresponding rate was 100%. The variant coefficient rate was less than 10%. A comparison of antigen sandwiched ELISA with indirect ELISA in detection of a panel(20 positive sera and 20 negative sera) from the NICPBP showed that the general coincident rate of indirect ELISA was 92.5% and the sandwiched system was 100%. The HIV-AS diagnostic reagent kits have passed the quality examination of NICPBP. A comparison of antigen sandwiched ELISA with Yapei reagents in detection of 90 normal sera and 88 positive sera for HIV-1/2 showed that the coincident rate was 100%. The reagents were stable at 37 degrees C for 4 days. This indicated that our reagents were highly specific, sensitive and stable. CONCLUSION: Our antigen sandwiched ELISA reagent for total antibodies of HIV has a merit of sensitivity specificity and stability. It can be clinically used for detection of HIV-1/2 infection and in blood bank for the screening of blood donors.

Adult↗

PubMed2001

[Influences of rearing style on the intellectual development of infants].

The factors causing the imbalance on intellectual development of infants in the early period after birth were studied and some better styles of rearing infants were found. The developmental quotient in 68 infants of 3-months-old was tested with Gesell Developmental Schedules and the style for rearing infants was obtained by inquiring their parents. The results showed that: (1) the development of adaptive behavior, language and personal--social behavior was better than that of gross motor and fine motor; (2) giving infants opportunity to move could make the development of adaptive behavior, gross motor and fine motor better. The development of fine motor could be hampered if a pair of mitten was put on hands to avoid scratching infant own face. Out doors activities were more important on the development of adaptive behavior, gross motor, fine motor and personal--social behavior; (3) in addition to the mother, with the cooperation of grandparents or father to look after infants was better. The higher education level of parents always associated with a better mental development of infants; (4) the complex structure with more people in a family make the development of language better. It is suggested that if parents have more knowledge on caring infants, give infants more opportunity to move and communicate with other people, it would be beneficial to the development of infants.

Child Development↗

PubMed2001

[The trends and preventive strategies of esophageal cancer in high-risk areas of Taihang Mountains, China].

OBJECTIVE: To analyze and predict the trends of incidence and mortality rates of esophageal cancer in areas of Taihang Mountains, and explore the strategies for facilitating the reduction of the incidence and mortality of esophageal cancer. METHODS: The data were collected from Linxian and Cixian Counties registries between 1988-1997. The trends of the incidence and mortality rates for esophageal cancer had been fitted and predicted by the model of BP (Back Propagation) Neural Networks. Then Linqi Xiang in Linxian County was taken as an example, to determine the power for reducing incidence and mortality of esophageal cancer using endoscopic technology as an early detection and treatment method. RESULTS: There were slowly declining trends for both incidence and mortality rates during past 10 years in Taihang Mountains. The predicting rates of the esophageal cancer incidence in 2,002 are 115. 70/100,000 for male and 79.88/100,000 for female; mortality rates are 94.00/100,000 and 56.29/100,000 respectively. Both incidence and mortality rates a still in high level. But when using endoscopic technology as an early detection and treatment method, the incidence rate is nearly 1/3 of a control group and the power is 88.30% at the end of eight years. The mortality rate is 1/4 of the control group and power is 89.44% after five years intervention (both powers based on 0.05 significant levels). CONCLUSIONS: The incidence and mortality rates for esophageal cancer are still on high levels in Taihang Mountains. We should continue to enhance our preventive effort there. After using endoscopic technology as an early detection and treatment method, the incidence and mortality rates will be decreased markedly during 5 to 8 years. It is recommended to implement a large-scale secondary prevention strategy in these areas.

China↗

PubMed2001

[Simultaneous determination of trace cadmium and arsenic in grains using atomic absorption spectrophotometry].

Simultaneous determination of two components in single wavelength using interferencing effect and atomic absorption spectrophotometry assisted by simulated annealing-back propagation of error-artificial neural networks algorithm was realized, and simultaneous determination of trace cadmium and arsenic in grains was studied. The results obtained are satisfactory. The recoveries found by standard addition method are 91%-98% and 87%-92% respectively. Relative standard deviations for 7 times of determinations are all less than 4%. This method is fast and simple.

Arsenic↗

PubMed2000

Nitric oxide induces oxidative stress and apoptosis in neuronal cells.

Within the central nervous system and under normal conditions, nitric oxide (NO) is an important physiological signaling molecule. When produced in large excess, NO also displays neurotoxicity. In our previous report, we have demonstrated that the exposure of neuronal cells to NO donors induced apoptotic cell death, while pretreatment with free radical scavengers L-ascorbic acid 2-[3, 4-dihydro-2,5,7,8-tetramethyl-2-(4,8, 12-trimethyltridecyl)-2H-1-benzopyran-6-yl-hydrogen phosphate] potassium salt (EPC-K1) or superoxide dismutase attenuated apoptosis effectively, suggesting that reactive oxygen species (ROS) may be involved in the cascade of events leading to apoptosis. In the present investigation, we directly studied the kinetic generation of ROS in NO-treated neuronal cells by flow cytometry using 2', 7'-dichloro-fluorescein diacetate and dihydrorhodamine 123 as redox-sensitive fluorescence probes. The results indicated that exposure of cerebellar granule cells to the NO donor S-nitroso-N-acetylpenicillamine (SNAP) induced oxidative stress, which was characterized by the accumulation of cytosolic and mitochondrial ROS, the increase in the extracellular hydrogen peroxide level, and the formation of lipid peroxidation products. SNAP treatment also induced apoptotic cell death as confirmed by the formation of cytosolic mono- and oligonucleosomes. Pretreating cells with the novel antioxidant EPC-K1 effectively prevented oxidative stress induced by SNAP, and attenuated cells from apoptosis.

Animals↗