Diagnosis of Tuberculosis by an Enzyme-Linked Immunospot Assay for Interferon-γ

*National Taiwan University Hospital, Taipei, Taiwan

Genetic Epidemiological Study on Association between Polymorphisms in Testosterone-Related Genes and Risk of Male Lung Adenocarcinoma in Taiwan

背景：肺癌是台灣癌症的首要死因，本研究探討睪固酮生成和代謝相關基因的基因多形性與台灣男性肺腺癌危險性的相關，包括：CYP17、SRD5A2 和 AR-CAG 重複序列數目的多形性。 方法：本研究是一病例對照研究，自2002年9月至2004年3月，以頻率配對方式選取來自台灣6個醫學中心的男性肺腺癌病例共357名與各醫院健檢中心的健康對照357名。受試者接受問卷訪視和提供血液樣本，以毛細管電泳和TaqMan 即時聚合酵素連鎖反應為基礎的方式分析AR-CAG 重複序列數目和CYP17及SRD5A2 基因的多形性。各基因多形性的危險對比值和95%信賴區間以非條件式羅吉斯迴歸模式進行分析。 結果：調整年齡、教育年數、香菸暴露（吸菸和二手菸暴露）、父親肺癌病史和曾經得過結核病等因子後，CPY17 A1/A1基因型相對於A2/A2和A2/A1基因型有1.46倍的危險性 (95%信賴區間=0.85-2.47)；SRD5A2 Val/Val基因型相對於Val/Leu和Leu/Leu基因型有1.79倍的危險性 (95%信賴區間=1.03-3.10 )；至於AR-CAG 重複序列數目的多形性和肺腺癌，則無相關。 結論：本研究發現睪固酮生成和代謝相關基因CPY17 A1/A1和SRD5A2 Val/Val多形性和男性肺腺癌的發生有關。Background: Lung cancer is the leading cause of cancer death in Taiwan. This study aimed to investigate the association of male lung adenocarcinoma and polymorphism of testosterone biosynthetic and metabolic pathway-related genes, including CYP17 and SRD5A2, and the number of CAG repeat length in the androgen receptor (AG) gene. Methods: A total of 357 male patients with lung adenocarcinoma and 357 healthy hospital controls selected by frequency matching were recruited at 6 medical centers in Taiwan from September 2002 to August 2004. These subjects had been interviewed by questionnaires and provided blood samples for analysis. The number of CAG repeat length in the AR gene and genetic polymorphisms of cytochrome17α (CYP17) and 5α-reductase type II (SRD5A2) were determined by capillary electrophoresis and TaqMan assays. Unconditional multivariate logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for each genotype. Results: After having adjusted for age, schooling year, cigarette smoking exposure, father with lung cancer, and tuberculosis, the ORs of developing lung adenocarcinoma were 1.46 (95% CI=0.85-2.47) for CYP17 A1/A1 genotype compared with A2/A2 and A2/A1 genotype and 1.79 (95% CI=1.03-3.10) for SRD5A2 Val/Val compared with Val/Leu and Leu/Leu genotypes. For AR-CAG repeats length, there was no any association with lung adenocarcinoma. Conclusion: Our result suggest that testosterone-related gene polymorphisms including CYP17 A1/A1 and SRD5A2 Val/Val might contribute to male lung adenocarcinoma in Taiwan.Contents Contents I Chinese Abstract 1 English Abstract 2 Chapter 1. Review of the Literature 3 1.1 Risk factors 4 1.2 Number of CAG repeat length in the AR gene 6 1.3 CYP17 gene polymorphisms 8 1.4 SRD5A2 gene polymorphisms 9 Chapter 2. Materials and Methods 11 2.1 Study subjects 11 2.2 Blood collection and DNA extraction 12 2.3 Analysis for the number of CAG repeat length in the AR gene 12 2.4 Genotyping 13 2.5 Statistical analysis 14 Chapter 3. Results 16 3.1 Demographic characteristics of study subjects 16 3.2 Ambient air pollution exposure of study subjects 16 3.3 Disease status of study subjects 17 3.4 Number of CAG repeat length in the AR gene 18 3.5 SNPs of testosterone biosynthetic and metabolic pathway-related genes 19 3.6 Genetic markers and environmental factor interaction 20 Chapter 4. Discussion 22 References 28 Contents of Tables Table 1.1 Summary of previous studies on associations between AR and prostate cancer risk 37 Table 1.2 Summary of the previous studies on associations between CYP17 and prostate cancer risk 39 Table 1.3 Summary of the previous studies on associations between SRD5A2 and prostate cancer risk 42 Table 2.1 Sequence of primer and probe sets for using TaqMan Technique 48 Table 3.1 Demographic characteristics of study subjects 49 Table 3.2 ORs and 95% CIs of cigarette smoking exposure for developing male lung adenocarcinoma 50 Table 3.3 ORs and 95% CIs of disease status for developing male lung adenocarcinoma among subjects and parents 52 Table 3.4 Distribution of the number of CAG repeat length in the AR gene and ORs and 95% CIs for developing male lung adenocarcinoma 53 Table 3.5 ORs and 95% CIs of SNPs of testosterone biosynthesis and metabolism pathway-related genes for developing male lung adenocarcinoma 54 Table 3.6 Gene-gene interaction between CYP17 and SRD5A2 for developing male lung adenocarcinoma 56 Table 3.7 ORs and 95% CIs of combined cigarette smoking exposure and SNPs of CYP17 and SRD5A2 genes for developing male lung adenocarcinoma 57 Contents of Figures Figure 1.1 Biosynthesis and metabolism pathway of androgen 59 Appendix Questionnaire for risk factors of male lung adenocarcinoma in genetic epidemiological study of pulmonary disease in Taiwan 6

Evaluation of an Automatic Polymerase Chain Reaction Assay for Identification of Mycobacterium Tuberculosis in Respiratory Specimens

We evaluated the performance of an automatic polymerase chain reaction ( PCR) detection system for identification of Mycobacterium tuberculosis in respiratory specimens. Six hundred and two respiratory specimens, including 557 sputa and 45 bronchial washing samples, were analyzed using the COBAS AMPLICOR Mycobacterium tuberculosis (MTB) test. The results were compared with those obtained from acid-fast microscopy, conventional culture, and clinical history. In cases of discrepancy between the results of the COBAS AMPLICOR MTB test and culture, the medical history of the patient was reviewed, the COBAS AMPLICOR MTB test was repeated, and the gene encoding M. tuberculosis superoxide dismutase was screened using PCR (SOD-PCR). Fourteen samples were excluded because the internal control test result was negative. Of 57 specimens that were culture positive for Mycobacterium species, 40 appeared to have growth of M. tuberculosis and 21 were smear positive for acid-fast bacteria. The sensitivity, specificity, and positive and negative predictive values for the COBAS AMPLICOR MTB test evaluated at our laboratory were 85.0% (34/40), 99.3% ( 544/ 548), 89.5% (34/38), and 98.9% (544/550), respectively. Three specimens that were culture positive for M. tuberculosis but negative by COBAS AMPLICOR MTB test were positive when rechecked by both COBAS AMPLICOR MTB test and SOD-PCR. Among the four specimens with positive reactions on both COBAS AMPLICOR MTB test and SOD-PCR that were culture negative, two were from patients who had been receiving antituberculosis treatment, one was from a patient who had been treated for tuberculosis for 1 year, and the other was from a patient who died of sepsis with adult respiratory distress syndrome. In more than 70% of smear-negative and culture-positive specimens and 86.4% of smear-positive specimens, M. tuberculosis was identified by the COBAS AMPLICOR MTB test within 10 hours after receipt of the specimens. Our data show that the COBAS AMPLICOR MTB test provides rapid and accurate detection of M. tuberculosis in respiratory specimens

鋇鹽中毒病例報告

Barium intoxication, a rare cause of hypokalemia, can sometimes result in respiratory paralysis and ventricular tachyarrhythmia. Herein, we report one such case. A 29-year- old man swallowed barium-contaminated fried flour-coated sweet potatoes. Then, abdominal discomfort, vomiting, diarrhea, progressive muscular weakness, apnea and ventricular tachycardia developed and laboratory data revealed profound hypokalemia. He regained his health after mechanical ventilation, anti-arrhythmic agent and aggressive potassium chloride supplement. Analysis of blood, urine and contaminated flour showed the presence of barium carbonate. Barium intoxication is a medical emergency which requires rapid therapy to prevent mortality

與肺炎球菌菌血症有關之低血糖

OBJECTIVES: To evaluate the prevalence and associated presentations of hypoglycemia in bacteremic pneumococcal infections, and serotypes of the isolates. METHODS: This was a retrospective study of 70 episodes of pneumococcal bacteremia that occurred in 2004 and 2005. RESULTS: We found hypoglycemia (plasma glucose<3.05 mmol/l)) in six (8.6%) episodes. The patients were three children (mean age 3 years 1 month; range 1 year 5 months-4 years 5 months) and three adults (mean age 73.3 years; range 63-84 years). One child with asplenia and cyanotic heart disease had primary pneumococcal bacteremia. Of the other two children, one had meningitis and the other pneumonia. All the adults had cancer with previous chemotherapy and multilobar pneumonia, which progressed rapidly to respiratory failure. All patients developed their first hypoglycemic episode within two hours after presentation. The average plasma glucose during hypoglycemia was 1.78+/-0.78 mmol/l (range 0.33-2.94 mmol/l). One child and all of the adults died. Serotypes of isolates were those usually associated with severe pneumococcal infection: 6B and 19F in the children; 3, 14, and 23F in the adults. Only the asplenic child had received pneumococcal vaccine. CONCLUSIONS: Hypoglycemia occurred in 8.6% of bacteremic pneumococcal infections and was associated with high mortality and serotypes that cause severe invasive disease. All patients suspected of having septicemia should have their glucose checked to avoid missing hypoglycemia leading to a worsening of their already poor condition

Antimicrobial Susceptibility Testing for Klebsiella Pneumoniae Isolates Resistant to Extended-Spectrum -Lactam Antibiotics

Detection of Klebsiella pneumoniae strains with extended- spectrum beta- lactamase (ESBL)-related resistance phenotypes is becoming important in clinical microbiology laboratories . In this study, we investigated the usefulness of three screening methods, the Etest ESBL screen, the double- disk synergy test, and the ceftazidime disk test, for identifying ESBL- producing K. pneumoniae strains. The agar dilution method was used as the standard. We also determined the in vitro activity of several new antimicrobial agents against these organisms. Strains that exhibited an increase in the minimum inhibitory concentration (MIC) to the third- generation cephalosporins or aztreonam of 2 micrograms/mL or more, but were susceptible to the three cephamycins tested, were considered to have ESBL-related resistance phenotypes. The frequency of ESBL-producing K. pneumoniae isolates ( according to the disk-diffusion method) has increased markedly in recent years, from 3.4% in 1993 to 10.3% in 1997 . A total of 93 preserved isolates of K. pneumoniae collected from December 1995 through March 1997 were found to be resistant to at least one of the third-generation cephalosporins (cefotaxime and ceftazidime) or aztreonam using the routine disk diffusion method. Among these isolates, 35 were classified as having an ESBL phenotype using the agar dilution method. The remaining 58 isolates were classified as cephamycin resistant, which indicated resistance to both cephamycins and third-generation cephalosporins or aztreonam. The susceptibility rates of the ESBL- producing isolates were 11% for cefotaxime, 14% for ceftazidime, and 6% for aztreonam. The susceptibility rates of these 35 isolates to imipenem, ciprofloxacin, and ofloxacin were 100%, 80%, and 86%, respectively. Both the MIC50 and MIC90 of meropenem were 0.06 microgram/mL, while the MIC50 and MIC90 of BAY 12-8039 were 0.125 and 2 micrograms/mL, respectively. Thirty-two (91%) of the 35 isolates of K. pneumoniae with the ESBL-related resistance phenotype were detected by the Etest ESBL screen, while the ceftazidime disk screen test detected 77% of these isolates, and the double-disk synergy test detected 74%. The Etest ESBL screen appears to be an acceptable, convenient, and sensitive method for the detection of ESBL -producing isolates in the clinical microbiology laboratory