PubMed Health⌕ Search

Biomedical subjects

B Huang

Publications and source records attributed to B Huang.

At least 37 records · Page 2Linked to original sources
PubMed2001

Alterations of sodium channel kinetics and gene expression in the postinfarction remodeled myocardium.

INTRODUCTION: After a myocardial infarction (MI), the heart undergoes a remodeling process that includes hypertrophy of noninfarcted left ventricular myocytes. Alterations in the genetic expression, including reexpression of fetal isogene patterns, can result in electrophysiologic changes that contribute to the arrhythmogenicity of post-MI heart. The present study investigated possible alterations in gene expression of Na+ channel subtypes, as well as the kinetics of the Na+ current (I(Na)), in 3- to 4-week-old post-MI rat remodeled left ventricular myocardium. METHODS AND RESULTS: Using a macropatch technique, we showed increased Na+ channel bursting activity during sustained depolarization in post-MI remodeled myocytes resulting in a large slow component of the I(Na) decay. A tetrodotoxin-sensitive current contributed 18% to the prolonged APD90 of isolated post-MI myocytes compared with 6% in control myocytes. Our molecular studies revealed that, in addition to the rat heart I (rH I) subtype, thought to be the predominant subtype that encodes a tetrodotoxin-resistant isoform, the brain subtypes NaCh I and NaCh Ia also are expressed in the rat myocytes. Post-MI remodeled myocardium showed increased expression of NaCh I protein with reversion of the NaCh Ia/NaCh I isoform ratio toward the fetal phenotype. CONCLUSION: Our findings raise the possibility that the increase in the slow component of I(Na) in post-MI remodeled myocytes is secondary to the increased expression of NaCh I. Additional studies are required to address these questions and to characterize the functional role of the NaCh I subtypes in cardiac myocytes.

Animals↗
PubMed2001

Calcineurin inhibition ameliorates structural, contractile, and electrophysiologic consequences of postinfarction remodeling.

INTRODUCTION: After myocardial infarction (MI), the heart undergoes an adaptive remodeling process characterized by hypertrophy of the noninfarcted myocardium. Calcineurin, a Ca2+-calmodulin-regulated phosphatase, has been shown to participate in hypertrophic signal transduction. METHODS AND RESULTS: We investigated the effects of calcineurin inhibition by cyclosporin A on key structural, contractile, and electrophysiologic alterations of post-MI remodeling. Male Sprague-Dawley rats were divided into four groups: (1) sham-operated; (2) sham + cyclosporin A; (3) post-MI (left anterior descending coronary artery ligation); and (4) MI + cyclosporin A. Cyclosporin A (25 mg/kg/day) was initiated 2 days before surgery and continued for 30 days. Hypertrophy was evaluated by echocardiography and by changes in membrane capacitance of isolated myocytes from noninfarcted left ventricle (LV). The effects of cyclosporin A on hemodynamics and cardiac dimensions were investigated, and changes in diastolic function were correlated with changes in protein phosphatase 1 activity and the basal level of phosphorylated phospholamban. The effects of cyclosporin A on Kv4.2/Kv4.3 genes expression and transient outward K+ current (I(to)) density also were evaluated. One of 12 rats in the post-MI group and 2 of 12 rats in the post-MI + cyclosporin A group died within 48 hours after MI. There were no late deaths in either MI group. There was no evidence of heart failure (lung congestion and/or pleural effusion) in the two groups 4 weeks post-MI. Calcineurin phosphatase activity increased 1.9-fold in post-MI remodeled LV myocardium, and cyclosporin A administration resulted in an 86% decrease in activity. There were statistically significant decreases of LV end-diastolic pressure, LV end-diastolic diameter, and LV relative wall thickness in the post-MI + cyclosporin A group compared with the post-MI group. On the other hand, there was no significant difference in LV end-systolic diameter or peak rate of LV pressure increase between the two post-MI groups. Protein phosphatase 1 activity was elevated by 36% in the post-MI group compared with sham, and this correlated with a 79% decrease in basal level of p16-phospholamban. In the post-MI + cyclosporin A group, the increase in protein phosphatase 1 activity was much less (18% vs 36%; P < 0.05), and the decrease in basal level of p16-phospholamban was markedly ameliorated (20% vs 79%; P < 0.01). The decreases in mRNA levels of Kv4.2 and Kv4.3 and I(to) density in the LV of the post-MI + cyclosporin A group were significantly less compared with the post-MI group. CONCLUSION: Our results show that calcineurin inhibition by cyclosporin A partially ameliorated post-MI remodeled hypertrophy, diastolic dysfunction, decrease in basal level of phosphorylated phospholamban, down-regulation of key K+ genes expression, and decrease of K+ current, with no adverse effects on systolic function or mortality in the first 4 weeks after MI.

Animals↗
PubMed2001

Management of heartburn in a large, randomized, community-based study: comparison of four therapeutic strategies.

OBJECTIVE: Our objective was to compare four management strategies for heartburn: therapy with an H2-receptor antagonist (ranitidine), therapy with a proton pump inhibitor (lansoprazole), crossover from ranitidine to lansoprazole ("step-up" therapy), and crossover from lansoprazole to ranitidine ("step-down" therapy). METHODS: This was a controlled, double-blind, multicenter trial comprising 593 adults with heartburn, randomized to one of four groups for 20 wk. Subjects received either ranitidine 150 mg b.i.d. for 20 wk, or lansoprazole 30 mg once daily for 20 wk, or ranitidine 150 mg b.i.d. for 8 wk [corrected] followed by lansoprazole 30 mg once daily for 12 wk ("step-up"), or lansoprazole 30 mg once daily for 8 wk followed by ranitidine 150 mg b.i.d. for 12 wk ("step-down"). Outcome measures were based on self-reports in daily diaries of 24-h heartburn severity, measured by maximum daytime and nighttime severity, and percentage of 24-h heartburn-free days measured by absence of both daytime and nighttime heartburn. RESULTS: Median heartburn severity was significantly lower (p < 0.05) for lansoprazole (0.25) than the other groups (0.46 ranitidine, 0.44 "step-up," 0.35 "step-down"). The lansoprazole group had a significantly higher percentage of 24-h heartburn-free days (median 81.4%, p < 0.01) than other groups (66.6, 66.9, and 73.6%, respectively). In the "step-up" and "step-down" groups, heartburn was less severe, and percentages of 24-h heartburn-free days were higher during lansoprazole treatment regardless of treatment sequence. CONCLUSION: Proton pump inhibitor treatment provides more consistent heartburn relief than an H2-receptor antagonist, or "step-up" or "step-down" therapy.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2001

Comparing lansoprazole and omeprazole in onset of heartburn relief: results of a randomized, controlled trial in erosive esophagitis patients.

OBJECTIVE: This randomized, double-blind, multicenter study was conducted to confirm a previous finding that lansoprazole relieves heartburn faster than omeprazole in patients with erosive esophagitis. METHODS: A total of 3510 patients with erosive esophagitis and at least one episode of moderate to very severe daytime and/or nighttime heartburn during the 3 days immediately before the screening visit were randomized to lansoprazole 30 mg once daily or omeprazole 20 mg once daily for 8 wk. Patients recorded the presence and severity of daytime and nighttime heartburn in daily diaries. On treatment days 1-4, patients were telephoned to confirm the completion of their daily diary. The primary efficacy parameters were the percentage of heartburn-free days and heartburn-free nights, as well as the average severity of daytime and nighttime heartburn. RESULTS: During treatment day I and all evaluation time points including the entire 8-wk treatment period, significantly (p < 0.05) higher percentages of patients treated with lansoprazole than those treated with omeprazole did not experience a single episode of heartburn. Onset of heartburn relief was more rapid in lansoprazole-treated versus omeprazole-treated patients: on day 1, 33% versus 25% of lansoprazole- versus omeprazole-treated patients were heartburn-free. The percentages of heartburn-free days and heartburn-free nights were also significantly (p < 0.01) greater for patients treated with lansoprazole at all evaluation time points. Heartburn severity was significantly less among those treated with lansoprazole compared with omeprazole. Both treatments were safe and well tolerated. CONCLUSIONS: Over 8 wk, lansoprazole 30 mg once daily relieved heartburn symptoms faster and more effectively than omeprazole 20 mg once daily in patients with erosive esophagitis.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2001

The social predictors of adolescent alcohol misuse: a test of the social development model.

OBJECTIVE: This study was conducted to investigate the ability of the social development model (SDM) to predict alcohol misuse at age 16 and to investigate the ability of the SDM to mediate the effects of alcohol use at age 14 on alcohol misuse at age 16. METHOD: The sample of 807 (411 males) is from the longitudinal panel of the Seattle Social Development Project which, in 1985, surveyed all consenting fifth-grade students from 18 elementary schools serving high-crime neighborhoods in Seattle, Washington. Alcohol use was measured at age 14, predictors of alcohol misuse were measured at age 15 and alcohol misuse was measured at age 16. Structural equation modeling was used to examine the fit of the model to the data. RESULTS: All factor loadings were highly significant and the measurement model achieved a good fit with the data (Comparative Fit Index [CFI] = 0.93). A second-order structural model fit the data well (CFI = 0.91) and also explained 45% of the variance in alcohol misuse at age 16. The SDM partially and significantly mediated the direct effect of age-14 alcohol use on age-16 alcohol misuse. CONCLUSIONS: The risk and protective processes specified by the SDM serve as potential targets for the prevention or reduction of adolescent alcohol misuse.

Adolescent↗
PubMed2001

Intention to return for papanicolaou smears in adolescent girls and young women.

OBJECTIVE: Sexually active adolescent girls have high rates of abnormal cervical cytology. However, little is known about factors that influence intention to return for Papanicolaou screening or follow-up. The aim of this study was to determine whether a theory-based model that assessed knowledge, attitudes, and behaviors predicted intention to return. METHODS: The study design consisted of a self-administered, cross-sectional survey that assessed knowledge, beliefs, perceived control over follow-up, perceived risk, cues for Papanicolaou smears, impulsivity, risk behaviors, and past compliance with Papanicolaou smear follow-up. Participants were recruited from a hospital-based adolescent clinic that provides primary and subspecialty care, and the study sample consisted of all sexually active girls and young women who were aged 12 to 24 years and had had previous Papanicolaou smears. The main outcome measure was intention to return for Papanicolaou smear screening or follow-up. RESULTS: The enrollment rate was 92% (N = 490), mean age was 18.2 years, 50% were black, and 22% were Hispanic. Eighty-two percent of participants intended to return. Variables that were independently associated with intention to return included positive beliefs about follow-up (odds ratio [OR]: 1.07; 95% confidence interval [CI]: 1.02-1.11), perception that important others believe that the participant should obtain a Papanicolaou smear (OR: 1.93; 95% CI: 1.38-2.74), perceived control over returning (OR: 1.24; 95% CI: 1.06-1.46), and having received cues to obtain a Papanicolaou smear (OR: 1.31; 95% CI: 1.08-1.60). CONCLUSIONS: Analysis of this novel theoretical framework demonstrated that knowledge and previous behaviors were not associated with intention to return for Papanicolaou smear screening and follow-up in this population of young women. However, modifiable attitudinal components, including personal beliefs, perception of others' beliefs, and cues to obtaining Papanicolaou smears, were associated with intention to return.

Adolescent↗
PubMed2001

Adoption as a risk factor for attempted suicide during adolescence.

OBJECTIVE: Depression, impulsivity, and aggression during adolescence have been associated with both adoption and suicidal behavior. Studies of adopted adults suggest that impulsivity, even more than depression, may be an inherited factor that mediates suicidal behavior. However, the association between adoption and adolescent suicide attempts and the mechanisms that might explain it remain unknown. The objective of this study was to determine the following: 1) whether suicide attempts are more common among adolescents who live with adoptive parents rather than biological parents; 2) whether the association is mediated by impulsivity, and 3) whether family connectedness decreases the risk of suicide attempt regardless of adoptive or biological status. METHODS: A secondary analysis of Wave I data from the National Longitudinal Study of Adolescent Health was conducted, which used a school-based, clustered sampling design to identify a nationally representative sample of 7th- to 12th-grade students, with oversampling of underrepresented groups. Of the 90 118 adolescents who completed the National Longitudinal Study of Adolescent Health in-school survey, 17 125 completed the in-home interview and had parents of identified gender who completed separate in-home questionnaire. The subset of adolescents for this study was drawn from the in-home sampling according to the following criteria: 1) adolescent living with adoptive or biological mother at the time of the interview, 2) adolescent had never been separated from mother for more than 6 months, 3) mother was in first marriage at the time of the interview, and 4) the adoptive mother had never been married to the adolescent's biological father. Of the 6577 adolescents in the final study sample, 214 (3.3%) were living with adoptive mothers and 6363 (96.7%) were living with biological mothers. Variables. The primary outcome measured was adolescent report of suicide attempt(s) in the past year. Other variables included in the analyses were sociodemographics characteristics (gender, age, race/ethnicity, family income, parental education), general health (self-rated health, routine examination in the past year, need for medical care in the past year that was not obtained), mental health (depressive symptoms, self-image, trouble relaxing in the past year, bad temper, psychological or emotional counseling in the past year), risk behaviors (cigarettes, alcohol, marijuana, sexual intercourse ever, delinquency, physical fighting in the past year, impulsive decision making), school-related characteristics (grade point average, school connectedness), and family interaction (family connectedness, parental presence, maternal satisfaction with parent-adolescent relationship). Data Analysis. Univariate analyses were used to compare adoptees versus nonadoptees, suicide attempters versus nonsuicide attempters, and adopted suicide attempters versus nonadopted suicide attempters on all variables. Variables that were associated with attempted suicide were entered into a forward stepwise logistic regression procedure, and variables that were associated with the log odds of attempt were retained in the model. The area under the model's receiver operating characteristic curve was calculated as a measure of its overall performance. After the association of adoption with attempted suicide was demonstrated, the potential mediating effect of impulsivity was explored by adding it to the model. The same procedure was followed for any variable that was associated with adoption in the full sample or the subsample of suicide attempters. To determine whether any variable in the model moderated the association between adoption and suicide attempt, the interaction term for that variable x adoption was forced into the model. RESULTS: Adoptees differed significantly from nonadoptees on 4 of 26 variables. They were more likely to have attempted suicide (7.6% vs 3.1%) and to have received psychological or emotional counseling in the past year (16.9% vs 8.2%), and their mothers reported higher parental education and family income. Attempters differed significantly from nonattempters on all variables except for age, race/ethnicity, parental education, family income, and routine examination in the past year. On logistic regression, 9 variables were independently associated with attempted suicide: depression (adjusted odds ratio [AOR]: 3.41), counseling (AOR: 2.83), female gender (AOR: 2.31), cigarette use (AOR: 2.31), delinquency (AOR: 2.17), adoption (AOR: 1.98), low self-image (AOR: 1.78), aggression (AOR: 1.48), and high family connectedness (AOR: 0.60). The receiver operating characteristic curve for the model had an area of 0.834, indicating performance significantly better than chance. The AOR for adoption did not change when parental education, family income, and impulsivity were forced into the model. (ABSTRACT TRUNCATED)

Achievement↗
PubMed2001

Adolescents' perceptions of social status: development and evaluation of a new indicator.

OBJECTIVE: Eliminating health disparities, including those that are a result of socioeconomic status (SES), is one of the overarching goals of Healthy People 2010. This article reports on the development of a new, adolescent-specific measure of subjective social status (SSS) and on initial exploratory analyses of the relationship of SSS to adolescents' physical and psychological health. METHODS: A cross-sectional study of 10 843 adolescents and a subsample of 166 paired adolescent/mother dyads who participated in the Growing Up Today Study was conducted. The newly developed MacArthur Scale of Subjective Social Status (10-point scale) was used to measure SSS. Paternal education was the measure of SES. Indicators of psychological and physical health included depressive symptoms and obesity, respectively. Linear regression analyses determined the association of SSS to depressive symptoms, and logistic regression determined the association of SSS to overweight and obesity, controlling for sociodemographic factors and SES. RESULTS: Mean society ladder ranking, a subjective measure of SES, was 7.2 +/- 1.3. Mean community ladder ranking, a measure of perceived placement in the school community, was 7.6 +/- 1.7. Reliability of the instrument was excellent: the intraclass correlation coefficient was 0.73 for the society ladder and 0.79 for the community ladder. Adolescents had higher society ladder rankings than their mothers (micro(teen) = 7.2 +/- 1.3 vs micro(mom) = 6.8 +/- 1.2; P =.002). Older adolescents' perceptions of familial placement in society were more closely correlated with maternal subjective perceptions of placement than those of younger adolescents (Spearman's rho(teens <15 years) = 0.31 vs Spearman's rho(teens 15 years) = 0.45; P <.001 for both). SSS explained 9.9% of the variance in depressive symptoms and was independently associated with obesity (odds ratio(society) = 0.89, 95% confidence interval = 0.83, 0.95; odds ratio(community) = 0.91, 95% confidence interval = 0.87, 0.97). For both depressive symptoms and obesity, community ladder rankings were more strongly associated with health than were society ladder rankings in models that controlled for both domains of SSS. CONCLUSIONS: This new instrument can reliably measure SSS among adolescents. Social stratification as reflected by SSS is associated with adolescents' health. The findings suggest that as adolescents mature, SSS may undergo a developmental shift. Determining how these changes in SSS relate to health and how SSS functions prospectively with regard to health outcomes requires additional research.

Adolescent↗
PubMed2001

Effects of calcium on antioxidant activities and water relations associated with heat tolerance in two cool-season grasses.

Calcium (Ca2+) may be involved in plant tolerance to heat stress by regulating antioxidant metabolism or/and water relations. This study was designed to examine whether external Ca2+ treatment would improve heat tolerance in two C(3), cool-season grass species, tall fescue (Festuca arundinacea L.) and Kentucky bluegrass (Poa pratensis L.), and to determine the physiological mechanisms of Ca2+ effects on grass tolerance to heat stress. Grasses were treated with CaCl(2) (10 mM) or H(2)O by foliar application and then exposed to heat stress (35/30 degrees C) in growth chambers. Some of the Ca2+ -untreated plants were maintained at 20/15 degrees C as the temperature control. Heat stress reduced grass quality, relative water content (RWC), and chlorophyll (Chl) content of leaves in both species, but Ca2+ treatment increased all three factors under heat stress. The Ca2+ concentration in cell saps increased with heat stress and with external Ca2+ treatment in both species. Osmotic potential increased with heat stress, but external Ca2+ treatment had no effect. Osmotic adjustment increased during short-term heat stress, but then decreased with a prolonged period of stress; it was not influenced by Ca2+ treatment. The activity of superoxide dismutase (SOD) in both species increased transiently at 12 d of heat stress and then remained at a level similar to that of the control. External Ca2+ treatment had no effect on SOD activity. The activities of catalase (CAT), ascorbate peroxidase (AP), and glutathione reductase (GR) of both species decreased during heat stress. Plants treated with Ca2+ under heat stress had higher CAT, GR and AP activities than untreated plants. Lesser amounts of malondialdehyde (MDA) accumulated in Ca2+ -treated plants than in untreated plants during extended periods of heat stress. The results suggested that exogenous Ca2+ treatment enhanced heat tolerance in both tall fescue and Kentucky bluegrass. This enhancement was related to the maintenance of antioxidant activities and a decrease in membrane lipid peroxidation, but not to the regulation of osmotic potential and osmotic adjustment.

Antioxidants↗
PubMed2001

Effects of cultivation on N2O emission and seasonal quantitative variations of related microbes in a temperate grassland soil.

Laboratory and in situ experiments were done to investigate the influences of cultivation on temperate semi-arid grassland (for 17 years spring wheat planted once every two years without fertilisation) on soil N2O emission and quantitative variations of related soil microbes. In the laboratory (25 degrees C and soil moisture 18%), cultivation increased soil transformations of fertilizer nitrogen (100 micrograms N/g as NaNO3, urea, or as urea with dicyandiamide 1 microgram N/g). The N2O emissions from the cultivated and uncultivated soils with or without nitrogen additions were relatively low, and mainly originated from the nitrification. The soil N2O emission due to cultivation decreased somewhat upon no fertilization or NaNO3 addition, but significantly upon urea addition. The role of dicyandiamide as nitrification inhibitor was only considerable in the cultivated soil, and had small influence on decreasing N2O emission in the two soils. The influence of cultivation on soil N2O emission was also reflected by the number variations of microbes related with soil nitrogen transformation in the two soils. Compared to the uncultivated grassland, in situ ammonifiers and denitrifiers in the cultivated grassland quantitatively averagely increased, and aerobic no-symbiotic azotobacters were quantitatively similar, leading to the continued decrease of organic matter content and the decrease of N2O emission from the cultivated grassland soil.

China↗
PubMed2001

[Decomposition interaction of mixed litter between Chinese fir and various accompanying plant species].

Studies on the decomposition of mixed litter between Chinese fir and 8 accompanying plant species showed that the decomposition of Chinese fir litter was promoted to different degrees by 8 mixed plant species, in which Angiopteris fokiensis had the greatest effect, while Schima superba had certain promotion first, but then, weak inhibition. The order of promotion was Angiopteris fokiensis > Maesa japonica > Ficus simplicissima > Woodwardia japonica > Boehmeria nivea > Castanopsis fargesii > Castanopsis fissa > Dicranopteris dicotoma. Chinese fir litter had a certain inhibition to litter decomposition of Schima superba and Castanopsis fissa, and certain promotion to litter decomposition of Castanopsis fargesii, but the interactions were not significant. There existed an interaction between Chinese fir and some plant species in the course of mixed decomposition. Therefore, rational protection and restoration of understory plant was important to fasten nutrient cycling of Chinese fir plantation ecosystem and to maintain soil fertility.

Abies↗
PubMed2001

[Age-structure dynamics and genetic consequences of Hippophea rhamnoides L. subsp sinensis clone population in Mu Su sandland].

Based on the measurement of all individuals of population at different successional stage, the investigation on edge dispersal effect and the following excavation of clones, the dynamics of age structure and genetic consequences of Hippophea rhamnoides L. subsp sinensis clone population in Mu Su sandland were examined. The results showed that the age structure of the clone population was characterized by a transformation from an increasing type in the early period starting from the initial colonization through a stable type to a declining type. The clone population could maintain or recover its stability by edge dispersal and gap regeneration with clonal growth. As the population self-thinned, the composition of clone population changed from more clones with less ramets to less clones with more ramets and the genetic diversity of clone population decreased.

Age Factors↗
PubMed2001

[Study of loss of heterozygosity at chromosome 11q13 in nasopharyngeal carcinoma].

OBJECTIVE: To analyze the loss of heterozygosity (LOH) from STS sites at 11q13 in nasopharyngeal carcinoma(NPC). METHODS: Relatively pure tumor tissues were obtained by microdissetion. PCR was used to perform microsatellite analysis of NPC samples using D11S4946, PYGM, D11S449 and INT-2 as primers, which span the MEN-1 gene. RESULTS: Thirty-six of 38 cases studied showed LOH in at least one of the loci analyzed. Among the primers used, D11S4946 had the highest frequency of LOH, (78.8%). The LOH frequency was 51.5% for INT-2, 45.5% for PYGM and 45.7% for D11S449, respectively. CONCLUSION: The high frequency of loss of heterozygosity at 11q13 in NPC implies that there may be some tumor suppressor gene(s) involved in NPC tumorigenesis.

Chromosomes, Human, Pair 11↗
PubMed2001

[Fine mapping of the loss of heterozygosity for chromosome 1pter-p36.11 in nasopharyngeal carcinoma].

OBJECTIVE: To construct a detailed mapping of the Chromosome 1pter-p36.11 deleted region (63.4 cM) in nasopharyngeal carcinoma (NPC) by polymerase chain reaction-loss of heterozygosity (PCR-LOH) analysis for the further research of NPC-related gene(s). METHODS: Biopsies from 47 cases of NPC patients were studied. DNA extracted from separated cancer cells and their corresponding non-cancer lymphocytes were amplified with PCR, followed by the analysis of LOH and microsatellite instability (MI) for 20 loci spanning Chromosome 1pter-p36.11 region with an average interval of 3.0 cM. RESULTS: 82.2% of NPC cases (37/47) showed at least one loci of LOH. The highest frequency of LOH was found at loci D1S234 on 1p36.13 (50.0%), with the LOH at loci D1S2644 on 1p36.22 slightly less (37.5%). The occurrence of LOH at D1S234 showed no significant difference for the cases at early stage and at advanced stage [60% (9/15) vs 50.0% (8/16) respectively, P > 0.05]. High frequencies of MI were detected at D1S243 on 1p36.33 (37.5%) and D1S199 on 1p36.21 (30.2%). CONCLUSIONS: There are two common deletion regions: one localized at 1p36.13 (D1S234, 2.0 cM) and the other at 1p36.22 (D1S436-D1S2644, 6.3 cM), with a MI loci at D1S199 between them. This suggests that one or more putative tumor suppressor gene(s) related to the early stage of NPC tumorigenesis may be encompassed in this zone.

Adult↗
PubMed2001

[Clinical significance of c-myc oncogene amplification in primary hepatocellular carcinoma by interphase fluorescence in situ hybridization].

OBJECTIVE: To investigate the relationships between c-myc oncogene amplification in primary hepatocellular carcinoma (HCC) and its clinical prognosis. METHODS: To detect c-myc oncogene amplification in 100 cases with primary HCC and in 6 cases with satellite nodes by interphase fluorescence in situ hybridization (FISH). RESULTS: c-myc amplification was detected in 92 of 100 (92%) cases with HCC, 37 of which (37%) showed high copy amplification (HC), 55 (55%) low copy amplification (LC) and 8 (8%) single copy or no amplification (SC). There wasn't statistically different significance between the frequency of c-myc amplification and clinical stage and tumor size, and pathological types (P > 0.05), however, in the 90 follow-up resected cases, the one-year rates of recurrence in HC, LC and SC were 70.6% (24/34), 39.6% (19/48) and 12.5% (1/8) respectively (P < 0.05) but the recurrence rates after more than one year were 14.70% (5/34), 14.6% (7/48) and 0 (0/8) respectively (P > 0.05). Meanwhile, two-year survival rate of patients with HC was significantly lower in comparison with those with LC and SC (P = 0.001). CONCLUSIONS: There is a high frequency of c-myc oncogene amplification in primary HCC and the fact that the patients with HC showed poorer prognosis indicates that the level of c-myc oncogene amplification may be a sensitive index in the prognosis of HCC.

Adult↗
PubMed2001

[Construction of cDNA library of Eimeria tenella sporulated oocysts].

A lambda ZAP express cDNA library was constructed using mRNA from Eimeria tenella sporulated oocysts. Total RNA was isolated by the TRIzol from Eimeria tenella sporulated oocysts, mRNA was further purified through oligo(dT)-cellulose columns. The first-strand cDNA was synthesized by using MMLV reverse transcriptase with oligo(dT)18 primers containing Xho I restriction site. After the second strand cDNA replacement synthesized, the uneven termini of the double-stranded cDNA were filled in with cloned Pfu DNA polymerase and EcoR I adapters were ligated to the blunt ends. Then the double-strand cDNA was digested with Xho I restriction enzyme. The fragments of 0.5 kb-4 kb were collected by agarose gel fraction method. After ligation of the cDNA with the lambda ZAP Express vector, the cDNA library was packaged using Gigapack III Gold Packaging extract. According to the phage plaques bright selection, the cDNA library contained 6 x 10(6) clones and the titer of the amplified library was 1 x 10(11) pfu/mL. By using PCR identification, the cDNA library contained approximately 96% recombinant phages.

Animals↗
PubMed2001

[Chinese Hans population study of fluorescent labelled 8 STR multiplex system].

OBJECTIVE: Chinese Hans population study of 8 STR loci was carried out in 350 unrelated individuals. METHODS: The 8 STR loci(vWA, TH01, TPOX, CSF1PO, D5S818, D13S317, D7S820, D16S539) and a sexual distinction locus Amelogenin, were amplified simultaneously in one PCR reaction tube, the products were separated by electrophoresis with PE-377 DNA sequencer, and analyzed by Genescan analysis software, then the accurate PCR fragment length and designation of genotypes were finished automatically by the sequencer. RESULTS: 63 alleles and 2 sex determination alleles were found in Hans population altogether; the minimum allele frequency in Chinese Hans population at these loci was 0.17%, the maximum was 50.17%; the fragments were 119-327 base pairs long; the TDP of this system reached 99.99999998%; this system inherited steadily, and was accord with Mandel inheritance rule, no gene mutation was found, all loci met Hardy-Weinberg equilibrium, but the frequencies of Hans population differed from those of African-Americans, Caucasion-Americans and Hispanic-Americans. CONCLUSION: This method is good for identification of little amount and degraded DNA samples from blood stain, semen stain mixed with vaginal excretion, hair root, cigarette root, muscle tissue and ancient bone. It can also make a foundation of establishing the National DNA Database.

Alleles↗