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Biomedical subjects

C F Huang

Publications and source records attributed to C F Huang.

At least 19 recordsLinked to original sources
PubMed2005

Familial aggregation of lung cancer in a high incidence area in China.

To investigate whether lung cancer clusters in families in a high incidence county of China, an analysis was conducted using data on domestic fuel history and tobacco use for family members of 740 deceased lung cancer probands and 740 controls (probands' spouses). Lung cancer prevalence was compared among first-degree relatives of probands and of controls, taking into account various factors using logistic regression and generalised estimating equations. First-degree relatives of probands, compared with those of controls, showed an excess risk of lung cancer (odds ratio (OR)=2.05, 95% confidence interval (CI): 1.68-2.53). Overall, female relatives of probands had a greater risk than did their male counterparts, and the risk was 2.90-fold for parents of probands as compared with parents of spouses. Female relatives of probands had 2.67-fold greater risk than female controls. Lung cancer risk was particularly marked among mothers (OR=3.78, 95% CI: 2.03-7.12). Having two or more affected relatives was associated with a 2.69-5.40-fold risk increase. The risk elevation was also found for other cancers overall. Results confirm previous findings of a genetic predisposition to lung cancer, and also imply that lung cancer may share a genetic background with other cancers.

Adult↗
PubMed2001

Disrupting the transforming activity of shrimp ras(Q(61)K) by deleting the CAAX box at the C-terminus.

BALB/3T3 cells were transformed by transfection with DNA encoding the mutated ras(Q(61)K) from shrimp Penaeus japonicus. Ras transcription and protein levels had increased significantly in the cells transfected with the S-ras plasmid, compared to cells transfected with a control plasmid pcDNA3.1. The bacterially expressed GTP-locked S-Ras(Q(61)K) is successfully prenylated by rat protein geranylgeranyltransferase I (PGGTase I) and then polymerized with tubulin, in agreement with findings for GTP-locked mammalian K(B)-Ras(Q(61)K) in vitro. Shrimp protein farnesyltransferase (PFTase) of shrimp did not prenylate the GTP-locked shrimp S-Ras(Q(61)K) (Lin and Chuang. 1998. J Exp Zool 281:565-573), whereas rat PFTase efficiently catalyzed the farnesylation of GTP-locked S-Ras(Q(61)K). To investigate the effect of geranylgeranylation on cellular transformation, we generated S-ras(Q(61)K) mutants with deletion of the CAAX box [S-ras(Q(61)K)(-caax)] or replacement of the CAAX box [S-ras(Q(61)K)(Kcaax)] or replacement of the arginine-rich domain [S-ras(Q(61)K)(K-Lys)] with corresponding sequences from rat K(B)-ras(Q(61)K). BALB/3T3 cells transfected with DNA encoding S-ras(Q(61)K), S-ras(Q(61)K)(KCAAX), S-ras(Q(61)K)(K-Lys) were transformed successfully, but S-ras(Q(61)K)(-CAAX) was defective in its ability to transform. Thus, prenylation at CAAX is required for transformation. Either the geranylgeranylated or the farnesylated S-Ras(Q(61)K) was endowed with abilities to transform. The arginine-rich region in S-Ras or the lysine-rich clusters from the rat K(B)-Ras appear not essential for activity to transform.

3T3 Cells↗
PubMed2001

A complex duplication created by gene targeting at the imprinted H19 locus results in two classes of methylation and correlated Igf2 expression phenotypes.

Imprinting of the mouse H19 and Igf2 genes is dependent on the presence of an intervening imprinting control region (ICR) situated 2 kb upstream of H19 and approximately 70 kb downstream of Igf2. Several recent studies have provided substantial evidence that the unmethylated maternal ICR acts as an insulator that prevents activation of Igf2 by a suite of enhancers downstream of the H19 gene. The methylated paternal ICR and H19 promoter have no activity, allowing sole activation of Igf2 expression. We have produced mice in which a duplication of the H19/Igf2 ICR produces, in each generation, two classes of methylation levels that correlated with two Igf2 imprinting phenotypes. One hypermethylated class also shows activation of the normally silent Igf2 gene, whereas the other hypomethylated class shows only slight activation of Igf2, in agreement with methylation's role in ICR function. This study describes a rare, possibly unique type of mutation that induces two distinct phenotypes in each generation.

Alleles↗
PubMed2001

Hiatal hernia size is the dominant determinant of esophagitis presence and severity in gastroesophageal reflux disease.

OBJECTIVE: Although reflux esophagitis is a multifactorial disease, the relative importance of these pathogenetic factors has not been clearly established. In this study, regression analysis was used to model the major determinants of esophagitis in patients with symptomatic gastroesophageal reflux disease (GERD). METHODS: Sixty-six GERD patients and 16 asymptomatic controls were evaluated. All patients underwent upper endoscopy, esophageal manometry, and 24-h pH monitoring. Esophagrams were performed in 38 of the GERD patients and all controls. Stepwise regression was performed using esophagitis severity as the dependent variable. Logistic regression was performed grouping subjects as controls, nonerosive GERD, or erosive esophagitis. RESULTS: Hiatal hernia size, lower esophageal sphincter pressure, esophageal acid exposure, and number of reflux episodes >5 min significantly correlated with esophagitis severity. Stepwise regression identified hiatal hernia size (p = 0.0001) and lower esophageal sphincter pressure (p = 0.0024) as significant predictors of esophagitis. Logistic regression also identified hiatal hernia size (chi2 = 17.07, p < 0.0001) and lower esophageal sphincter pressure (chi2 = 5.97, p = 0.0146) as significant predictors of erosive esophagitis. CONCLUSION: Esophagitis severity is best predicted by hiatal hernia size and lower esophageal sphincter pressure. Of these, hiatal hernia size is the strongest predictor.

Adult↗
PubMed2001

Exposure of workers to airborne microorganisms in open-air swine houses.

This study quantified the levels of airborne microorganisms in six swine farms with more than 10,000 pigs in subtropical Taiwan. We evaluated breeding, growing, and finishing stalls, which were primarily open-air buildings, as well as partially enclosed farrowing and nursery piggeries. Airborne culturable bacteria, gram-negative bacteria, and fungi were placed on appropriate media by using an all-glass impinger or single-stage Andersen microbial sampler. Results showed that mean concentrations of culturable bacteria and gram-negative bacteria were 3.3 x 10(5) and 143.7 CFU/m(3), respectively. The concentration of airborne culturable fungi was about 10(3) CFU/m(3), with Cladosporium the predominant genus. The highest airborne levels of culturable bacteria and gram-negative bacteria were identified in the finishing units. The air of the nursery stalls was the least contaminated with culturable and gram-negative bacteria. Irregular and infrequent cleaning, high pig density, no separation of wastes from pen floors, and accumulation of water as a result of the processes for cleaning and reducing pig temperature possibly compromise the benefits of the open characteristic of the finishing units with respect to airborne bacterial concentration.

Air Microbiology↗
PubMed2001

Increased prevalence of gastroesophageal reflux symptoms in patients with COPD.

STUDY OBJECTIVES: To determine the prevalence of gastroesophageal reflux (GER) symptoms in patients with COPD and the association of GER symptoms with the severity of airways obstruction as assessed by pulmonary function tests (PFTs). DESIGN: Prospective questionnaire-based, cross-sectional analytic survey. SETTING: Outpatient pulmonary and general medicine clinics at a Veterans Administration hospital. PATIENTS: Patients with mild-to-severe COPD (n = 100) were defined based on American Thoracic Society criteria. The control group (n = 51) consisted of patients in the general medicine clinic without respiratory complaints or prior diagnosis of asthma or COPD. INTERVENTION: Both groups completed a modified version of the Mayo Clinic GER questionnaire. RESULTS: Compared to control subjects, a greater proportion of COPD patients had significant GER symptoms defined as heartburn and/or regurgitation once or more per week (19% vs 0%, respectively; p < 0.001), chronic cough (32% vs 16%; p = 0.03), and dysphagia (17% vs 4%; p = 0.02). Among patients with COPD and significant GER symptoms, 26% reported respiratory symptoms associated with reflux events, whereas control subjects denied an association. Significant GER symptoms were more prevalent in COPD patients with FEV(1) < or %, as compared with patients with FEV(1) > 50% of predicted (23% vs 9%, respectively; p = 0.08). In contrast, PFT results were similar among COPD patients with and without GER symptoms. An increased number of patients with COPD utilized antireflux medications, compared to control subjects (50% vs 27%, respectively; p = 0.008). CONCLUSIONS: The questionnaire demonstrated a higher prevalence of weekly GER symptoms in patients with COPD, as compared to control subjects. There was a trend toward higher prevalence of GER symptoms in patients with severe COPD; however, this difference did not reach statistical significance. We speculate that although GER may not worsen pulmonary function, greater expiratory airflow limitation may worsen GER symptoms in patients with COPD.

Aged↗
PubMed2001

[Immunologic properties of coli surface antigen 6(CS6) of enterotoxigenic Escherichia coli and cholera toxin subunit B expressed in Shigella flexneri 2a strain T32].

A host-plasmid balancing system composed with a delta asd mutant (FaD) of an avirulent strain (T32) of Shigella flexneri 2a and plasmid harboring asd gene was used to express enterotoxigenic E. coli surface antigen 6(CS6) and V. cholerae toxin subunit B (CTB). The results of Western blotting and ELISA showed that all of recombinant plasmids (pYX201, pYX202 and pYX203) could be maintained stably and expressed CS6 and CTB respectively in T32 without any antibiotic selection. All the recombinant bacterial strains could elicit the corresponding antibodies in rabbits. The antibodies against CTB elicited by both FaD/pYX201 and FaD/pYX203 showed to be high level, and had long prolongation time, in otherwise, the antibodies against CS6 showed to be low level, indicating that higher expression level of foreign antigen may be benefit for construction of genetic multivalent vaccine.

Animals↗
PubMed2001

Chronic granulomatous disease: a case report.

Chronic granulomatous disease is one form of the phagocyte function disorder. Unlike most patients with chronic granulomatous disease who develop signs and symptoms of chronic and recurrent pyogenic infections during the first 2 years of life, patients with mild forms of the disease may not present until the teenage years or even adulthood. Thus, the diagnosis in these mild-form patients is often delayed. This paper describes a patient with the mild form of chronic granulomatous disease. A 7-year-old boy was admitted to our ward with intermittent high fever and a left neck mass present for about 1 week. He had a history of persistent infection in the bilateral lower face lasting for about 1 year during his fourth year of life. Family history was unremarkable except that the patient's elder sister had a history of persistent oral mucosal wound infection for about 1 year during the fifth year of life. On physical examination, there were scars over the patient's bilateral lower face. Bacterial culture of pus drained from the neck mass revealed Burkholderia cepacia, a rare species in patients without immunodeficiency. A series of antibiotics, including oxacillin, clindamycin, and piperacillin, was given, and two incision operations for drainage and debridement were performed. The neck mass resolved completely about 1.5 months later. This history indicated that the patient might have chronic granulomatous disease. A definite absence of superoxide activity in the patient's granulocytes detected by chemiluminescence and nitroblue tetrazolium dye test confirmed this diagnosis.

Child↗
PubMed2001

Exposure assessment to airborne endotoxin, dust, ammonia, hydrogen sulfide and carbon dioxide in open style swine houses.

Information is limited for the exposure levels of airborne hazardous substances in swine feed buildings that are not completely enclosed. Open-style breeding, growing and finishing swine houses in six farms in subtropical Taiwan were studied for the airborne concentrations of endotoxin, dust, ammonia, hydrogen sulfide and carbon dioxide. The air in the farrowing and nursery stalls as partially enclosed was also simultaneously evaluated. Three selected gases and airborne dusts were quantified respectively by using Drager diffusion tubes and a filter-weighing method. Endotoxin was analyzed by the Limulus amoebocyte lysate assay. Average concentration of airborne total endotoxin among piggeries was between 36.8 and 298 EU/m(3), while that for respirable endotoxin was 14.1-129 EU/m(3). Mean concentration of total dust was between 0.15 and 0.34 mg/m(3), with average level of respirable dust of 0.14 mg/m(3). The respective concentrations of NH3, CO2 and H2S were less than 5 ppm, 600-895 ppm and less than 0.2 ppm. Airborne concentrations of total dust and endotoxin in the nursery house were higher than in the other types of swine houses. The finishing house presented the highest exposure risk to NH3, CO2 and H2S. Employees working in the finishing stalls were also exposed to the highest airborne levels of respirable endotoxin and dust. On the other hand, the air of the breeding units was the least contaminated in terms of airborne endotoxin, dust, NH3, CO2 and H2S. The airborne concentrations of substances measured in the present study were all lower than most of published studies conducted in mainly enclosed swine buildings. Distinct characteristics, including maintaining swine houses in an open status and frequent spraying water inside the stalls, significantly reduce accumulation of gases and airborne particulates.

Air Pollution, Indoor↗
PubMed2001

A comparison of clinical use of fluticasone propionate and beclomethasone dipropionate in pediatric asthma.

Inhaled steroids play a very important role in the prevention and treatment of asthma. Previous studies indicated that fluticasone propionate (FP) had low bioavailability and high local potency. However, the laboratory data in these studies were not obtained among Taiwan population. It is very important that native data should be established. Thus a 12-week research program was designed, involving 77 patients, 51 for FP group and 26 for beclomethasone dipropionate (BD) group. The objects were victims of moderate to severe asthma and their age ranged from 4 to 14 years old. An open, comparative and randomized method was adopted. Except for the 4-week-later daytime symptom score(P = 0.033, BD group was better), no other significant differences were found between the two groups in the symptom score improvement(P > 0.05). All the P-values for the daytime & night-time scores were lower than 0.001, which means obvious improvement after treatment in both groups. P-value for PEF improvement was 0.003 after 4 weeks (BD group was better) and 0.943 after 8 weeks; for FEV1 improvement, it was 0.005 after 4 weeks(BD group was better) and 0.252 after 8 weeks; and for FEV1/FVC improvements, it was 0.067 after 4 weeks and 0.097 after 8 weeks. There was no statistic significance in total eosinophil count (TEC), IgE, eosinophil cationic protein (ECP) serum level changes after 4 or 8 weeks. Adverse effects were all anticipated and no statistic significance showed up, either, between the two groups or in the cortisol levels (P > 0.05). In conclusion, native data indicated that the potency of 100 micrograms of FP was equal to that of 200 micrograms of BD and that few side effects were noted in FP group. It is recommended that this drug be introduced for clinical use.

Adolescent↗
PubMed2001

Construction of a novel display vector deriving from CS3 fimbriae of human enterotoxigenic Escherichia coli.

Based on the prediction of the hydrophilicity, epitopes, secondary structure and flexibility of the CS3 subunit, a novel vector pCSX72 which permits the insertion of foreign epitopes into CS3 at the position of 72nd aa was constructed. Two epitopes, the VP1 of FMDV and a ten-peptides epitope of C-myc, were displayed with it respectively. Compared with the two previously-constructed vectors, the vector pCSX72 expressed the hybrid fimbriae in higher level. Mice produced dual immune response against the CS3 and the inserted epitopes when they were immunized by injecting the live recombinant bacteria intraperitoneally.

Animals↗
PubMed2001

[Expression of C3 epitope of poliovirus and a ten-peptides epitope of C-myc on the surface of recombinant bacteria].

To confirm the possibility of pCSB136 and pCSX72 as vectors for displaying heterologous epitopes, the gene fragments coding for C3 epitope of poliovirus and a ten-peptides epitope of C-myc were synthesized and inserted into pCSB136 and pCSX72 respectively. The recombinants were screened by whole-strain PCR. The expression of recombinant proteins were detected by whole-cell ELISA and electronic microscopy. The results indicated the recombinant proteins were expressed as hybrid fimbriae, and the antigenicity of both CS3 and inserted epitopes kept. All results above showed vectors pCSB136 and pCSX72 could be used to display the foreign epitopes.

Capsid↗
PubMed2001

Unruptured aneurysm of sinus of Valsalva with right ventricular outflow tract obstruction.

Aneurysm of the sinus of Valsalva (ASV) is a rare anomaly. It may be congenital or acquired basis. In pediatric patients, most are congenital in origin. It is frequently associated with other congenital disease, most frequently ventricular septal defect (VSD). Pathologically, this is due to the total absence of normal elastic fibers. Patients with ASV are generally asymptomatic unless aneurysm rupture occurs. Unruptured ASV with right ventricular outflow tract (RVOT) obstruction is very rare. Herein we describe an unusual ASV with RVOT obstruction associated with VSD in a 14-year-old boy. He had experienced heart failure and exertional dyspnea for 2 months. The diagnosis was made by echocardiography, angiography and surgery. After surgical repair of the VSD and resection of the ASV, dyspnea and heart failure were relieved. The patient remained well during the 3 years of follow-up.

Adolescent↗
PubMed2001

Perinatal cytomegalovirus infection complicated with pneumonitis and adrenalitis in a premature infant.

Cytomegalovirus causes pneumonia, hepatitis, thrombocytopenia, and hemolytic anemia. Cytomegalovirus adrenalitis in premature infants, however, is rare. This report described a premature newborn who had progressively worsening hyperbilirubinemia, pancytopenia, and hepatosplenomegaly at the age of 4 days. The baby's mother had prolonged rupture of amniotic membrane for about 8 weeks. The infant received exchange blood transfusion, empiric antibiotics treatment, and mechanical ventilation. Pneumonia and sepsis developed at the age of 18 days. Serum anticytomegalovirus immunoglobulin M and urine virus culture were positive for cytomegalovirus. The baby died at the age of 22 days. Autopsy showed cytomegalovirus infection complicated with interstitial pneumonitis and pulmonary edema, subacute bronchopulmonary dysplasia with interstitial fibrosis, and adrenalitis. We concluded that the functional status of the adrenal glands in cytomegalovirus-infected premature newborns who have unexplained electrolytes imbalance, fever, diarrhea, weight loss, or hypotension should be closely followed because of the possible involvement of adrenal glands.

Adrenal Gland Diseases↗
PubMed2000

ARL4, an ARF-like protein that is developmentally regulated and localized to nuclei and nucleoli.

ADP-ribosylation factors (ARFs) are highly conserved approximately 20-kDa guanine nucleotide-binding proteins that participate in both exocytic and endocytic vesicular transport pathways via mechanisms that are only partially understood. Although several ARF-like proteins (ARLs) are known, their biological functions remain unclear. To characterize its molecular properties, we cloned mouse and human ARL4 (mARL4 and hARL4) cDNA. The appearance of mouse ARL4 mRNA during embryonic development coincided temporally with the sequential formation of somites and the establishment of brain compartmentation. Using ARL4-specific antibody for immunofluorescence microscopy, we observed that endogenous mARL4 in cultured Sertoli and neuroblastoma cells was mainly concentrated in nuclei. When expressed in COS7 cells, ARL4-T34N mutant, predicted to exist with GDP bound, was concentrated in nucleoli. Yeast two-hybrid screening and in vitro protein-interaction assays showed that hARL4 interacted with importin-alpha through its C-terminal NLS region and that the interaction was not nucleotide-dependent. Like ARL2 and -3, recombinant hARL4 did not enhance cholera toxin-catalyzed auto-ADP-ribosylation. Its binding of guanosine 5'-O-(thiotriphosphate) was modified by phospholipid and detergent, and the N terminus of hARL4, like that of ARF, was myristoylated. Our findings suggest that ARL4, with its distinctive nuclear/nucleolar localization and pattern of developmental expression, may play a unique role(s) in neurogenesis and somitogenesis during embryonic development and in the early stages of spermatogenesis in adults.

ADP-Ribosylation Factors↗
PubMed2000

Induction of mitosis-mediated apoptosis by sodium arsenite in HeLa S3 cells.

Arsenic has been used effectively as a chemotherapeutic drug for the treatment of acute promyelocytic leukemia patients. Numerous studies have demonstrated that arsenic induces apoptosis in various cell types. In the present study, we showed that approximately 35% of arsenite-treated HeLa S3 cells arrested in mitosis. After release from arsenite treatment, more than 80% of arsenite-arrested mitotic cells subsequently underwent apoptosis, as indicated by anachronistic nuclear envelope reformation, DNA ladder occurrence, chromatin condensation, and activation of caspases 3 and 9. In exploring how these cells entered apoptosis mechanistically, we found an inverse correlation between mitotic indexes and apoptotic frequencies. As shown by using Percoll density gradient fractionation and flow cytometric analysis, the mitosis-mediated apoptosis induced by arsenite was accompanied by delayed cyclin B degradation and altered mitotic exit. Furthermore, treatment of arsenite-arrested mitotic cells with staurosporine or 2-aminopurine resulted in a rapid degradation of cyclin B, moved these cells forward to interphase without cell division, and abrogated apoptosis. These results suggest that apoptosis occurs in arsenite-arrested mitotic cells that exit mitosis abnormally.

Apoptosis↗