Reactivation of precore mutant hepatitis B virus in chemotherapy-treated patients

BACKGROUND

A point mutation from G to A at nucleotide (nt) 1896 of the precore region of hepatitis B virus (HBV) DNA has been shown to be associated with fulminant and severe hepatitis. Further studies have suggested that this point mutation, together with additional mutations in the precore promoter, is probably linked to the reactivation of HBV in patients undergoing cytotoxic chemotherapy. Taiwan is an area with a high prevalence of HBV where hepatitis B flare-up has become a serious problem of HBV carriers who must rely on chemotherapy to treat their diseases. The purpose of this study was to examine if nt 1896 mutation was also present in Chinese patients in Taiwan who developed severe liver disease after chemotherapy. MATERIALS AND METHODS. Thirteen HBV carrier patients, including eight patients with lymphoma, two with germ cell tumors, two with breast carcinomas, and one with acute myeloid leukemia, received chemotherapy in the authors' hospital from February 1994 to May 2000. They all received steroid-containing regimens or antiemetics during chemotherapy. These patients were monitored closely for the development of severe hepatitis during or after chemotherapy. Their sera were harvested at different times for direct sequencing of the polymerase chain reaction products of the precore region of HBV DNA.

RESULTS

Six of the 13 patients developed severe hepatitis with a fulminant course during or after the completion of chemotherapy. A point mutation from G to A at nt 1896 was detected in five of these six patients. Among those five patients, four had additional precore mutations. The other patient did not have the nt 1896 mutation but had mutations at nt 1835 (A to C). None of the other seven patients lacking the precore nt 1896 mutation developed severe hepatitis flare-up. One of those seven patients who developed moderate elevation of alanine aminotransferase (ALT) without hyperbilirubinemia did have precore mutations other than nt 1896. None of the other six patients had mutations over the precore region.

CONCLUSIONS

Nucleotide mutation of the precore region, notably at position 1896, is associated with reactivation of HBV with a fulminant course during or after chemotherapy. The current data, together with other investigators' findings, suggest that patients who are HBV carriers with HBV envelope antigen (HBeAg) (-)/anti-HBV envelope antibody (Anti-HBe)(+) status should be assayed to determine if they carry mutant HBV before chemotherapy. Prophylactic use of lamivudine is strongly recommended for patients who carry mutant HBV at precore region, especially at nt 1896 (G to A), before and during chemotherapy.

Tumor necrosis factor-alpha induces the expression of DR6, a member of the TNF receptor family, through activation of NF-kappaB

The tumor necrosis factor (TNF) receptor family are ligand-regulated transmembrane proteins that mediate apoptosis as well as activation of the transcription factor NF-kappaB. Exogenous expression of DR6, a recently identified member of the TNF receptor family, induced apoptosis in untransformed or tumor-derived cells and the apoptotic function of DR6 was inhibited by co-expression of Bcl-2, Bcl-x(L) or the inhibitor-of-apoptosis (IAP) family member, survivin. Expression of a dominant negative mutant of FADD failed to protect from DR6-mediated apoptosis indicating that unlike TNFR1 and Fas, DR6 induced apoptosis via a FADD-independent mechanism. Despite the ability of exogenous DR6 expression to induce apoptosis, DR6 mRNA and protein were found to be elevated in prostate tumor cell lines and in advanced stages of prostate cancer. Analysis of several anti-apoptotic proteins revealed that Bcl-x(L) levels and serine 32 phosphorylation of IkappaB, the natural inhibitor of NF-kappaB, were similarly elevated in cells expressing high levels of DR6, suggesting that NF-kappaB-regulated survival proteins may protect from DR6-induced apoptosis and that DR6 is a target of NF-kappaB regulation. Treatment of LnCAP cells with TNF-alpha resulted in increases in both DR6 mRNA and protein levels, and this induction was suppressed by inhibitors of NF-kappaB. Similarly, treatment of cells expressing high levels of DR6 with indomethacin and ibuprofen, compounds also known to perturb NF-kappaB function, resulted in a dose-dependent decrease in DR6 protein and mRNA levels. These results demonstrate that TNF-alpha signaling induces the expression of a member of its own receptor family through activation of NF-kappaB.

[The research progress of the association of mitochondrial DNA mutation with cardiomyopathy]

There are some human diseases associated with mitochondrial DNA genome defect. Now many studies think that: oxygen radical resulting from oxidative phosphorylation(OXPHOS) disorder caused by myocardium ischemia and the increased OXPHOS induction damage mitochondrial DNA. Chronic damage accumulations lead to mitochondrial DNA deletion or point mutation in the end which show mitochondrial DNA 5.0 kb or 7.4 kb deletion and point mutation at position C15452A in the cytochrome b gene; the conservative sequence mutation of tRNA gene such as A4300G, C4320T point mutation in the tRNA Ilegene, A3243G point mutation in the tRNA leu gene etc result in defective contractile proteins whose persistent and inefficient contraction may increase the myocardium's metabolic demands for ATP and leads to cardiac hypertrophy. In this article, we review the study on the association of mitochondrial DNA mutation with ischemic cardiomyopathy and hypertrophic cardiomyopathy.

A comparison of methods for yeast identification including CHROMagar Candida, Vitek system YBC and a traditional biochemical method

BACKGROUND

CHROMagar Candida (CAC) is a new chromogenic medium for the presumptive identification of clinically-important yeast isolates. A yeast biochemical card (YBC), a part of the Vitek system is an automatic method for the identification of clinically-important yeast isolates. We conducted a comparison of these two methods with a traditional biochemical method in order to choose a rapid and accurate technique for yeast identification.

METHODS

All yeast isolates were inoculated onto Sabourand dextrose agar (SDA) and CAC, and incubated at 30 degrees C for 48 hours. All isolates were simultaneously tested using traditional biochemical methods and the yeast biochemical card from the Vitek system.

RESULTS

We evaluated 235 yeast isolates from clinical specimens, including 89 Candida albicans, 47 Candida tropicalis, 43 Candida glabrata, six Trichosporon beigelii, and five Candida krusei in addition to 45 isolates of other yeast species. Isolates were presumptively identified on the basis of colony color and appearance on CAC medium. These observations were compared with a traditional biochemical yeast-identification method and also with YBC from the Vitek system. For five commonly-isolated species (Candida albicans, Candida tropicalis, Candida glabrata, Candida krusei and Trichosporon beigelii), agreement among the CAC medium, YBC method and traditional biochemical method were 98.9% (187/189), 96.3% (182/189), 100% (189/189), respectively.

CONCLUSIONS

From our comparison, the CAC medium is a convenient and economic method to identify five commonly-noted yeast species, and the YBC method warrants a greater cost and requires a longer period of time to obtain reliable results.

High prevalence of VanB2 vancomycin-resistant Enterococcus faecium in Taiwan

Thirty-six VanB glycopeptide-resistant Enterococcus faecium isolates were collected from patients in five different hospitals in Taiwan. The vancomycin resistance genes were amplified by the long vanB PCR, which amplifies the 6,373-bp vanB gene cluster including the vanR(B2), vanS(B2), vanY(B2), vanW(B2), vanH(B2), vanB2, and vanX(B2) genes. The deduced amino acid sequences were found to be 95 to 98% homologous to those of the vanB1 gene cluster: VanR(B1), 97%; VanS(B1), 97%; VanY(B1), 96%; VanH(B1), 95%; VanB1, 96%; and VanX(B1), 98%. Restriction enzyme analysis of the long vanB PCR products revealed that all 36 isolates had the same vanB2-specific pattern. DNA sequence analysis of the vanB2 gene, which is a D-Ala-D-Lac ligase gene, revealed that none of the 36 sequences were identical to the previously published vanB2 sequence. Thirty-one isolates had 1 nucleotide different from the published vanB2 sequence. The sequences of the other five isolates differed from the published vanB2 sequence by 2 or 3 nucleotides. Four isolates with a low or moderate resistance to vancomycin (MIC = 4 to 32 microg/ml) were found to have the same leucine-to-methionine change at amino acid position 308 of the vanB2 gene. The genomic DNAs of all 36 isolates were digested with SmaI and then typed by pulsed-field gel electrophoresis (PFGE). Eight different PFGE types (I to VIII) were observed, and type I was found to be prevalent in all hospitals examined in this study. This result suggests that intra- and interhospital dissemination of this E. faecium strain has occurred in Taiwan.

Effects of chromium nicotinate on performance, carcase characteristics and blood chemistry of growing turkeys

1. The objective of this trial was to study the effects of chromium nicotinate (Cr) supplementation on the performance, carcase characteristics and blood constituents of 9 to 22 week-old male turkeys. 2. Fifty-four 8-week-old male turkeys weighing 2.9 +/- 0.28 kg were allocated at random into 9 groups with 3 dietary treatments and 3 replicates. The dietary treatment was different dietary concentrations of chromium in the basal diet, to provide 0 (control), 1 or 3 mg/kg. The feeding trial lasted for 14 weeks. 3. Results showed that 1 mg/kg chromium supplementation significantly improved weight gain and food intake at 9 to 18 weeks of age but did not significantly influence performance at 19 to 22 week of age. The breast and thigh muscle were significantly increased in birds receiving 1 mg/kg chromium supplementation but were decreased by 3 mg/kg of supplementation. 4. Dietary chromium supplementation did not significantly influence other serum constituents, including insulin, HDL, VLDL+LDL, HDL-C, VLDL-C+LDL-C, total protein, albumin, and gamma-globulin at 18 and 22 weeks of age. 5. The serum triacylglycerol (TG) and uric acid contents were significantly increased, while glycerol and alpha-globulin were significantly reduced by 3 mg/kg chromium supplementation. However, 1 mg/kg chromium supplementation significantly reduced serum cholesterol and glycerol at 18-weeks old. At 22 weeks of age, 1 mg/kg chromium supplementation significantly increased serum glucose and decreased the uric acid concentration whereas 3 mg/kg chromium supplementation significantly increased the creatinine concentration and decreased beta-globulin concentration.

Detection and typing of vancomycin-resistance genes of enterococci from clinical and nosocomial surveillance specimens by multiplex PCR

Ninety-three clinical isolates of vancomycin-resistant enterococci (VRE) collected from nine hospitals in Taiwan were examined for the presence of vanA, vanB, vanC1, or vanC2/vanC3 genes by a multiplex PCR. Forty-seven of these VRE isolates were vanA positive, 1 contained both vanC1 and vanA, 40 harboured vanB, 2 were vanC1, and 3 were identified to be vanC2/vanC3. Twenty-four vanA isolates were sensitive to teicoplanin and thus did not have a typical VanA phenotype. Five isolates with the VanC phenotype harboured vanB. None of the 40 clinically isolated vancomycin-susceptible E. faecium or E. faecalis and the vancomycin-resistant Leuconostoc and Pediococcus isolates were positive for any of the van genes. While performing nosocomial surveillance, VRE were isolated from 47 of 467 rectal swabs by culture. Compared with the conventional culture method, the sensitivity and specificity of the multiplex PCR for detecting and identifying vancomycin-resistance genes in enterococci directly from culture-positive broth were 97.9% and 100%, respectively. The results suggest that genotypic characterization of vancomycin-resistance is necessary for all clinical VRE isolates and that the multiplex PCR assay can be an alternative method for this purpose.

Quinupristin-dalfopristin resistance among gram-positive bacteria in Taiwan

To understand quinupristin-dalfopristin resistance among clinical isolates of gram-positive bacteria in Taiwan, where this agent is not yet available for clinical use, we evaluated 1,287 nonduplicate isolates recovered from January 1996 to December 1999 for in vitro susceptibility to quinupristin-dalfopristin and other newer antimicrobial agents. All methicillin-susceptible Staphylococcus aureus (MSSA) isolates were susceptible to quinupristin-dalfopristin. High rates of nonsusceptibility to quinupristin-dalfopristin (MICs, >/=2 microg/ml) were demonstrated for the following organisms: methicillin-resistant S. aureus (MRSA) (31%), coagulase-negative staphylococci (CoNS) (16%), Streptococcus pneumoniae (8%), viridans group streptococci (51%), vancomycin-susceptible enterococci (85%), vancomycin-resistant Enterococcus faecalis (100%), vancomycin-resistant Enterococcus faecium (66%), Leuconostoc spp. (100%), Lactobacillus spp. (50%), and Pediococcus spp. (87%). All isolates of MSSA, MRSA, S. pneumoniae, and viridans group streptococci were susceptible to vancomycin and teicoplanin. The rates of nonsusceptibility to vancomycin and teicoplanin were 5 and 7%, respectively, for CoNS, ranging from 12 and 18% for S. simulans to 0 and 0% for S. cohnii and S. auricularis. Moxifloxacin and trovafloxacin had good activities against these isolates except for ciprofloxacin-resistant vancomycin-resistant enterococci and methicillin-resistant staphylococci. In Taiwan, virginiamycin has been used in animal husbandry for more than 20 years, which may contribute to the high rates of quinupristin-dalfopristin resistance.

Apoptosis may be an early event of progestin therapy for endometrial hyperplasia

OBJECTIVE

The aim of this study was to investigate the role of apoptosis during progestin therapy for the treatment of endometrial hyperplasia.

METHODS

Pre- and posttreatment paraffin-embedded endometrial tissue samples from 19 women with endometrial hyperplasia were examined for changes in glandular cellularity and apoptotic activity related to the administration of progestins. Twelve patients were successfully treated with progestin therapy and 7 patients failed treatment. Glandular cellularity was assessed based on calculating the average number of cells per gland obtained on histologic examination of hematoxylin and eosin stained tissue sections. Apoptotic activity was assessed on the same tissue sections by counting the average number of apoptotic cells per 10 high power fields (hpf) using the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling (TUNEL) assay. The effects of progesterone on apoptotic activity in a low-grade endometrial adenocarcinoma cell line (Ishikawa cells) was also examined using an ELISA cell death detection kit.

RESULTS

Glandular cellularity significantly decreased with progestin therapy in both treatment outcome groups. The reduction in cells per gland was significantly greater in the group of successfully treated cases compared to the treatment failures (P = 0.005). However, within the successfully treated group, in situ detection of apoptotic cells using the TUNEL assay showed no statistical difference between pre- and posttreatment endometrial samples. Interestingly, a significant decrease in apoptosis was found in posttreatment samples of the group with persistent hyperplasia. The average number of apoptotic cells detected in 10 hpf was reduced from 7.9 prior to treatment to 3.1 after progestin therapy (P = 0.03). In the progesterone-treated Ishikawa cell line, an increase in apoptotic activity started at 24 h, reached a peak at 48 h, and continued up to 72 h of hormone treatment. At 48 h, apoptotic activity was 42.6% greater than in the untreated control (P = 0.04). By 72 h of progesterone treatment, apoptosis was 37.2% greater in the treated cells compared to the noninoculated cells (P = 0.04).

CONCLUSIONS

Progestin-induced apoptosis may occur during the early period of treatment for endometrial hyperplasia. Compared to the fully responsive group, persistent endometrial hyperplasia may have intrinsically different molecular mechanisms in response to progestin therapy.

Decreased luteinizing hormone receptor mRNA expression in human ovarian epithelial cancer

OBJECTIVES

The objective of this study was to examine the distribution and cellular localization of luteinizing hormone receptor (LHR) in ovarian epithelial tumors (OETs) and their presumed precursor lesions-ovarian epithelial inclusions (OEIs). The clinicopathologic correlation of the receptor expression in OET was also examined.

METHODS

Fifteen microdissected samples of ovarian surface epithelium (OSE), 20 OEIs from benign ovaries, and 141 OETs, including 48 cystadenomas, 33 borderline tumors, 60 carcinomas, and 5 metastatic cancers, were examined for LHR expression by using reverse transcription polymerase chain reaction and in situ hybridization. LHR expression in tumor epithelium and tumor stroma was analyzed separately. The clinicopathologic correlation data were analyzed by standard analysis of variance and contingency table methods.

RESULTS

LHR expression was identified in the majority of OSE and OEI samples. In OETs, LHR positivity was found in the epithelial cells in 27% of cases and in the stromal compartment in 37% of cases. LHR-positive stromal cells were mainly luteinized cells. Within the tumor epithelium, LHR expression was detected in 42% of benign, 24% of borderline, and 17% of malignant OETs. LHR expression in tumor stroma showed a similar trend of reduction from benign to malignant OETs. Within the 17 carcinomas, LHR was expressed in the epithelium in 47% of grade 1, 12% of grade 2, and only 5% of grade 3 cancers. The mean age of the LHR-positive group was younger than that of the receptor-negative patients. Compared with mucinous and other types of OETs, serous OETs showed higher LHR expression in the epithelium. Compared with the OETs removed in the different menstrual phases, OETs in the secretory phase showed higher LHR in the tumor stroma than in the proliferative phase. No receptor mRNA was detected in the epithelium of five carcinomas metastatic to the ovary. LHR transcription splicing variants from a single previous report were confirmed in this study.

CONCLUSIONS

Malignant OETs have significant reduction of LHR expression compared with precursor lesions and benign and borderline OETs. LHR expression shows a steady decline from low-grade to high-grade ovarian cancer. The presence of LHR receptor in tumor epithelium suggests that luteinizing hormone in serum may have direct influence on tumor growth, whereas the receptor in tumor stroma may be indicative of a paracrine function of LH in the development of OETs.

Detection of circulating cancer cells by reverse transcription-polymerase chain reaction for uroplakin II in peripheral blood of patients with urothelial cancer

Few attempts have been made at the molecular detection of urothelial cancer cells in the blood or lymph nodes mainly because of an absence of good candidate molecular or genetic changes specific to urothelial cancer or urothelium. In 1990, however, genes that encode urothelium-specific transmembrane proteins, uroplakins (UPs), were cloned. We have established a method of detecting circulating cancer cells in peripheral blood of patients with transitional cell carcinoma by nested reverse transcription-PCR assay for UP II. UP II mRNA-positive cells were detected in 3 (10.3%) of 29 patients with superficial cancers (pTa-1N0M0), 4 (28.6%) of 14 patients with muscularly invasive cancers (pT2-4N0M0), 2 (40.0%) of 5 loco-regional node-positive patients (pN1-2M0), and 6 (75.0%) of 8 patients with distant metastases. Positive rates, therefore, increased with tumor extension (P = 0.0033, Kruskal-Wallis test). Furthermore, sequential blood sampling was performed in three patients with metastases during and after systemic chemotherapy, and UP-II-positive cells were found to have disappeared in two patients who responded well to the systemic chemotherapy. These results suggest that our nested reverse transcription-PCR assay for UP II is highly specific and might be used as a tumor marker for molecular staging of urothelial cancers, although the sensitivity is not so optimal.

Tumor stroma as the main source of inhibin production in ovarian epithelial tumors

PROBLEM

Elevated serum inhibin levels have been found in ovarian cancer patients; however, the source of the elevated inhibin is uncertain. Previous studies of activin in human ovarian cancer suggest that activin may promote the growth of the tumor. The aims of this study were to examine the source of elevated inhibin from ovarian epithelial tumors (OETs) and to preliminarily investigate the role of the gonadotropin-inhibin/activin relationship in the development of OET.

METHOD OF STUDY

The protein and mRNA expression of alpha and betaA subunits of inhibin/activin were examined by immunohistochemistry (IHC) and reverse transcription polymerase chain reaction (RT-PCR) in 120 OETs, including 30 benign cystadenomas, 30 borderline tumors, and 60 carcinomas. Stromal and epithelial cells were microdissected from 23 OETs to further examine the expression of alpha and betaA subunits by RT-PCR. Dimeric inhibin A and activin A production were measured by using the two-site ELISA from three OET cell lines in culture under treatment of follicle-stimulating hormone (FSH) and luteinizing hormone (LH).

RESULTS

betaA subunit was expressed in the epithelial component of 100% of the cystadenomas, in 80% of borderline tumors, and in 75% of the carcinomas, but not in tumor stroma. Inhibin alpha expression was not found in the epithelium of all OETs studied, but focal inhibin alpha immunoreactivity was seen in the tumor stroma (mainly luteinized stromal cells) in the majority of cases. Dimeric activin A was produced by all of the three OET cell lines with a 1.5-1.9-fold increment after FSH stimulation. However, activin A production was not augmented by LH treatment. No inhibin A was produced by the three OET cell lines with or without gonadotropin stimulation.

CONCLUSIONS

The stroma of OET is the major source in the production of inhibin alpha (monomer). Dimeric inhibin A production may be the result of combined efforts of the tumor stroma (alpha subunit) and epithelium (betaA subunit). Cellular, compartmental expression of inhibin and activin subunits may play a role in the development of OET, although the mechanism remains undefined. The unopposed activin A production stimulated by FSH in OET cell lines suggests that activin production may represent one of the cellular mechanisms of growth promotion by FSH.

Use of PCR with universal primers and restriction endonuclease digestions for detection and identification of common bacterial pathogens in cerebrospinal fluid

We have designed a universal PCR capable of amplifying a portion of the 16S rRNA gene of eubacteria, including Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pyogenes, Streptococcus agalactiae, Streptococcus pneumoniae, Enterococcus faecium, Enterococcus faecalis, Mycobacterium tuberculosis, Legionella pneumophila, Escherichia coli, Klebsiella pneumoniae, Serratia marcescens, Enterobacter cloacae, Pseudomonas aeruginosa, Acinetobacter baumannii, Proteus mirabilis, Haemophilus influenzae, and Neisseria meningitidis. The sizes of the amplified products from various bacteria were the same (996 bp), but the restriction patterns of most PCR products generated by HaeIII digestion were different. PCR products from S. aureus and S. epidermidis could not be digested by HaeIII but yielded different patterns when they were digested with MnlI. PCR products from S. pneumoniae, E. faecium, and E. faecalis yielded the same HaeIII digestion pattern but could be differentiated by AluI digestion. PCR products from E. coli, K. pneumoniae, S. marcescens, and E. cloacae also had the same HaeIII digestion pattern but had different patterns when digested with DdeI or BstBI. This universal PCR could detect as few as 10 E. coli or 250 S. aureus organisms. Compared with culture, the sensitivity of this universal PCR for detection and identification of bacteria directly from 150 cerebrospinal fluids was 92.3%. These results suggest that this universal PCR coupled with restriction enzyme analysis can be used to detect and identify bacterial pathogens in clinical specimens.

Characterization of a highly glycopeptide-resistant Enterococcus gallinarum isolate

BACKGROUND AND PURPOSE

Adequate treatment of emergency infection involving antibiotic-resistant bacteria such as vancomycin-resistant Enterococcus requires a convergence of clinical and bacteriologic techniques. An isolate of Enterococcus gallinarum, designated as TSGH63, is known to be uncommonly vancomycin-resistant. This study investigated the genetic determinant for this unique characteristic.

METHODS

After completing the conventional identification and sensitivity tests, the genomic content of E. gallinarum TSGH63 was extracted and analyzed by pulse-field electrophoresis. A set of specific primers for vanA, vanB, vanC1, and vanC2/C3 genes was then applied in a multiplex polymerase chain reaction (PCR) to differentiate its genetic content. To locate the determinant for high vancomycin resistance, the electrophoresis profile was further analyzed by Southern blot using the digoxigenin (DIG)-labeled vanA gene probe. Finally, interspecies transfer of the vancomycin-resistance determinant of E. gallinarum TSGH63 was tested by a conjugation experiment in vitro.

RESULTS

A 50-kb plasmid was identified in the analysis of the genomic extract of E. gallinarum TSGH63 by pulse field electrophoresis. Using multiplex PCR, we demonstrated that E. gallinarum TSGH63 harbors a vanA gene in addition to a vanC1 gene. The DIG-labeled vanA gene-specific probe bound to the plasmid exclusively on the Southern blot. The plasmid-carried vanA gene, but not the vanC1 gene, was found to be transferable from TSGH63 to E. faecalis JH2-2 by conjugation in vitro.

CONCLUSIONS

This is the first report of isolation of E. gallinarum with a high level of resistance to glycopeptides in Taiwan. The demonstrated interspecies transfer of the vancomycin-resistance gene highlights the importance of stringent control of the use of vancomycin.

Reduction of BRCA1 expression in sporadic ovarian cancer

OBJECTIVE

The purpose of this study was to examine BRCA1 expression and its relationship to cell proliferation in sporadic ovarian epithelial tumors (OETs).

METHODS

We investigated BRCA1 expression and cell proliferative activity in 72 unselected OETs. They comprised 16 benign cystadenomas, 18 borderline (low malignant potential) tumors, and 38 carcinomas (OECs). These patients had no known family history of breast and/or ovarian cancer. BRCA1 and the cell proliferation marker, MIB-1, expressions in fixed tissue were investigated in all 72 cases by immunohistochemistry (IHC). BRCA1 mRNA in fresh frozen tissue samples from 20 of these cases was measured by a semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) method.

RESULTS

The average percentage of BRCA1-positive cells was 5.6% in cystadenomas, 29.7% in borderline tumors, and 6.6% in OECs. The average decreased steadily with increasing grade of OECs: grade 1 (21.4%), grade 2 (1.1%), and grade 3 (0%). The average percentage of MIB-1-positive cells increased steadily from cystadenomas (7.5%) to borderline tumors (22.6%) to carcinomas (41.2%). BRCA1 expression was highly correlated with MIB-1 expression in cystadenomas and borderline tumors. Six of seven OECs negative for BRCA1 by IHC showed low levels of BRCA1 mRNA by RT-PCR.

CONCLUSIONS

BRCA1 expression paralleled cell proliferation in benign and borderline OETs, but not in OECs. Sporadic OECs showed significantly reduced levels, rather than complete loss, of BRCA1 expression. The reduction was closely related to tumor grade. Reduction of BRCA1 expression may be of etiologic significance in the occurrence and progression of sporadic ovarian cancer.

Tuberculosis of skeletal muscle in a case of polymyositis

We describe a patient with polymyositis receiving corticosteroid therapy, who presented with persistent fever and mass lesion at the left thigh. Surgical exploration and mycobacterial culture proved to be Mycobacterium Tuberculosis infection involving the semitendinous muscle of the left thigh. Suitable surgical debridement, anti-TB medications, and sufficient corticosteroid administration resulted in a good control of both polymyositis and the tuberculous infection.

Characterization of the first clinical isolate of vancomycin-resistant Enterococcus faecalis, AH803, in Taiwan

We previously isolated a vancomycin-resistant strain of Enterococcus faecalis, designated AH803, from the sputum of a patient with pneumonia and bacteremia in Taiwan. AH803 was resistant to vancomycin (minimal inhibitory concentration, MIC = 512 micrograms/mL) but susceptible to teicoplanin (MIC = 8 micrograms/mL), and harbored the vanA gene but not the vanB gene. In this study, we further characterized E. faecalis AH803 and the plasmid it was found to contain. DNA from AH803 was analyzed for the presence of vanA and vanB resistance genes by polymerase chain reaction. The vancomycin resistant phenotype was transferable from AH803 to E. faecalis JH2-2, at a frequency of 4.8 x 10(-2). AH803 was also resistant to gentamicin and chloramphenicol, and these antibiotic resistance phenotypes cotransferred with vancomycin resistance. The genes responsible for resistance to all three antibiotics were located on a 42-kb conjugative plasmid (pBL101). This plasmid had the same restriction enzyme digestion patterns as Tn1546, found in pIP816 of E. faecalis BM4147. Epidemiologic studies of glycopeptide resistance should perhaps combine phenotypic and genotypic methods, rather than using phenotypic methods alone.

Ovarian epithelial tumor growth promotion by follicle-stimulating hormone and inhibition of the effect by luteinizing hormone

OBJECTIVES

The role of gonadotropins in ovarian epithelial cancer development is still controversial. Follicle-stimulating hormone receptor (FSHR) status in ovarian epithelial tumors (OETs) and their presumed precursor lesions has never been studied in detail. The objective of this study was to examine whether FSHR is expressed in OETs and to investigate the possible different roles of the gonadotropins in ovarian cancer development.

METHODS

Twenty ovarian epithelial inclusions (entrapments or invaginations of ovarian surface epithelium) from benign ovaries and 60 OETs including 12 cystadenomas, 18 borderline tumors, and 30 carcinomas were examined for FSHR expression by using reverse transcription polymerase chain reaction (RT-PCR), in situ hybridization (ISH), and immunohistochemistry (IHC). We also studied the mitogenic activity of FSH on two FSH and luteinizing hormone (LH) receptor-positive ovarian epithelial carcinoma cell lines (AO and 3AO) and on the modifying effect of LH on this activity. Growth-stimulating effects of the gonadotropins were tested in vitro with measurement of cell numbers, S-phase by flow cytometry, and changes in the cellular proliferative marker Ki-67.

RESULTS

Positive FSHR mRNA expression by RT-PCR (the most sensitive method) was found in 100% of epithelial inclusions, 100% of cystadenomas, 94% of borderline tumors, and 60% of carcinomas. There was a nonstatistically significant trend of decreasing positivity with increasing carcinoma grade. ISH and IHC gave similar, but somewhat less sensitive, results. A dose-response effect was seen with FSH, with a 1.6-fold increase in cell numbers with a maximally stimulating FSH concentration of 40 IU/L for a period of 48 h. These proliferative cellular effects were not observed when the cells were stimulated by LH in the range 1 to 100 IU/L. Most significantly, the growth stimulating effects of FSH could be blocked by the simultaneous administration of LH.

CONCLUSIONS

FSHR is present in the majority of ovarian epithelial inclusions and OETs. The steady decline of FSHR expression from benign cystadenoma to borderline tumor to carcinoma suggests that FSH may be needed in early ovarian cancer development. Gonadotropins, FSH and LH, may have different roles in ovarian cancer cell proliferation. FSH, not LH, may be an important ovarian epithelial cell growth-promoting factor. The "opposing" effect of LH on FSH stimulation may explain why high FSH levels at postmenopausal ages are not associated with great increases in ovarian cancer risk.

Alcohol metabolism and cardiovascular response in an alcoholic patient homozygous for the ALDH2*2 variant gene allele

BACKGROUND

Alcohol metabolism is one of the biological determinants that can influence drinking behavior. Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) are the principal enzymes involved in ethanol metabolism. Allelic variation of the ADH and ALDH genes can significantly affect vulnerability for the development of alcoholism. Homozygosity of the variant ALDH2*2 allele previously was believed to fully protect East Asian populations against the development of alcoholism.

METHODS

Eighty Han Chinese alcoholics who met DSM-III-R criteria for alcohol dependence and 144 nonalcohol-dependent subjects were recruited and their data combined with data from 340 alcohol-dependent and 545 nonalcohol-dependent subjects described in an earlier report (Chen et al., 1999) to assess risk for alcoholism by logistic regression analysis. Genotypes of ADH2, ADH3, and ALDH2 were determined by polymerase chain reaction and restriction fragment length polymorphism. The ALDH2 genotype was confirmed by direct nucleotide sequencing. Blood ethanol concentration was determined by headspace gas chromatography and acetaldehyde concentration by high-performance liquid chromatography with fluorescence detection of the derivatized product. Cardiovascular hemodynamic parameters were measured by two-dimensional Doppler echocardiography and sphygmomanometry. Extracranial arterial blood flow was measured by Doppler ultrasonography.

RESULTS

An alcohol-dependent patient was identified to be ALDH2*2/*2, ADH2*2/*2, and ADH3*1/*2. Following challenge with a moderate oral dose of ethanol (0.5 g/kg of body weight), the patient exhibited peak concentrations for ethanol (55.7 mg/dl) and acetaldehyde (125 microM). During 130 min postingestion, the patient generally displayed similar or even less intense cardiovascular hemodynamic alterations when compared to a previously published study of nonalcoholic individuals with ALDH2*2/*2 who had received a lower dose of ethanol (0.2 g/kg). Logistic regression analysis of the combinatorial genotypes of ADH2 and ALDH2 in 420 alcohol-dependent and 689 nonalcohol-dependent subjects indicated that risk for alcoholism was 100-fold lower for the ADH2*2/*2-ALDH2*2/*2 individuals than the ADH2*1/*1-ALDH2*1/*1 individuals.

CONCLUSIONS

The gene status of ALDH2*2/*2 alone can tremendously but not completely (as thought previously) protect against development of alcohol dependence. Individuals carrying the combinatorial genotype of ADH2*2/*2-ALDH2*2/*2 are at the least risk for the disease in East Asians. Physiological tolerance or innate insensitivity to the accumulation of blood acetaldehyde following alcohol ingestion may be crucial for the development of alcoholism in individuals homozygous for ALDH2*2.

Tuberculous meningitis in a Filipino maid

Tuberculous meningitis, while not uncommon in Taiwan, has not been reported among foreign workers. We report the first case of tuberculous meningitis in a 37-year-old Filipino maid in Taiwan, who presented with headache, fever and vomiting. She had been well before this episode and the small screening films of the chest radiograph obtained on her arrival in Taiwan 15 months previously, and every 6 months thereafter showed no evidence of tuberculosis. The suspicion of tuberculous meningitis was delayed until disturbance of consciousness manifested and a standard chest radiograph showed a diffuse miliary pattern in both lung fields. A cerebrospinal fluid sample that was sent for a polymerase chain reaction-based assay specific for Mycobacterium tuberculosis showed a positive result. The patient recovered with sequelae of mildly incoherent speech and urinary incontinence after antituberculous medication and short-course steroid treatment. Clinicians should be aware of the possibility of tuberculous meningitis in foreign workers with complaints of fever and headache. Because high-quality chest radiographs are a prerequisite for early detection of pulmonary tuberculosis, we recommended that standard posterior-anterior chest radiographs should be obtained as part of the routine health examination for foreign workers.

Varicella arthritis diagnosed by polymerase chain reaction

We report a 2-year-old girl who developed acute arthritis of the left knee 4 days after the onset of a typical varicella infection. She was first thought to have pyogenic arthritis caused by Staphylococcus aureus. Accordingly, oxacillin was administered upon hospitalization. On the third day after hospitalization, bacterial cultures of the synovial fluid and blood showed no growth and oxacillin was discontinued. Although a viral culture of the synovial fluid for varicella-zoster virus (VZV) was negative, varicella DNA was identified by means of polymerase chain reaction (PCR) with VZV-specific primers. The patient recovered spontaneously. To differentiate this condition from septic arthritis is important. PCR is a sensitive technique that can demonstrate the presence of VZV DNA in synovial fluid, even if viral cultures are negative.

Antimicrobial susceptibility of Clostridium difficile by E test

The in vitro inhibitory activity of 11 antimicrobials against 44 clinical isolates of Clostridium difficile was investigated. Minimum inhibitory concentrations (MICs) were determined using E test. Metronidazole (MIC90 0.38 microg/mL), teicoplanin (MIC90 0.75 microg/mL) and vancomycin (MIC90 1.0 microg/mL) were very active against the isolates examined, whereas, resistance to imipenem, cefoxitin, clindamycin and ciprofloxacin was found in most of the tested strains. We concluded that teicoplanin warrants clinical trials to determine its adequate dosage to treat C. difficile infection. The commonly used regimens to treat intra-abdominal and/or anaerobic infections (eg. imipenem, cefoxitin, clindamycin or ciprofloxacin) need special attention, while considering the side effects of C. difficile-associated diarrhea.

Comparison of five PCR methods for detection of Helicobacter pylori DNA in gastric tissues

Five different PCR methods for the detection of Helicobacter pylori were evaluated. The results of this study indicate that of the five PCR methods examined, the ureC (glmM) gene PCR is the most sensitive and specific for the detection of H. pylori in gastric biopsy specimens.

Antimicrobial susceptibilities of clinical isolates of vancomycin-resistant enterococci in Taiwan

To understand the antimicrobial resistance patterns of vancomycin-resistant enterococci in Taiwan, we tested the in vitro activities of 10 antimicrobial agents against 71 clinical isolates (39 of Enterococcus faecalis and 32 of Enterococcus faecium) by means of the agar dilution method. Resistance was determined on the basis of the minimum inhibitory concentration (MIC) of each antimicrobial agent--MIC50 and MIC90 (minimum concentrations required to inhibit growth of 50% and 90% of isolates, respectively) were determined. No beta-lactamase producers were identified with the cefinase test. All E. faecalis isolates were susceptible to penicillin and ampicillin, and 97% of these isolates were resistant to teicoplanin (vanA phenotype). Of the E. faecium isolates, 75% were susceptible to teicoplanin (vanB phenotype) and most were resistant to penicillin (94%) and ampicillin (94%). Quinupristin/dalfopristin was markedly less active against E. faecalis than E. faecium isolates (MIC50, 64 vs 2 micrograms/mL; MIC90, 128 vs 8 micrograms/mL; susceptibility rates, 3% vs 81%). Five of the eight vanA phenotype E. faecium isolates and one of the 24 vanB phenotype E. faecium isolates were resistant to quinupristin/dalfopristin. The activity of rifampin was also species-specific, with E. faecium being markedly less susceptible to this agent than E. faecalis (MIC50, 16 vs 1 microgram/mL; MIC90, 64 vs 4 micrograms/mL). Our data suggest the potential of teicoplanin and quinupristin/dalfopristin as appropriate antimicrobial agents in the treatment of infections caused by vanB phenotype E. faecium. Penicillin, ampicillin, and rifampin alone, or preferably in combination with other agents, appear to be the most appropriate agents for the treatment of vancomycin-resistant E. faecalis infections in Taiwan.

Determination of copy number of rRNA genes in Pneumocystis carinii f. sp. hominis

Differential PCR was performed to determine the copy number of rRNA genes in Pneumocystis carinii f. sp. hominis. Two different reference genes, thymidylate synthase (TS) and beta-tubulin (BTU) genes, were used. Primers for the internal transcribed spacer (ITS) region of nuclear rRNA genes and either the TS or BTU gene were mixed together to perform PCR on seven different bronchoalveolar lavage specimens from patients with P. carinii pneumonia. The radioactivity derived from the incorporated radioactive nucleotides of each PCR product band was then used to calculate the copy number of the ITS relative to that of the TS or BTU gene. The copy number ratio between the ITS and the TS gene was determined to be 0.8, and that between the ITS and the BTU gene was also 0.8. These results suggest that the ITS has the same copy number as the TS or BTU gene. Since the copy number of the TS or BTU gene is presumed to be 1, the results also suggest that P. carinii f. sp. hominis has only one copy of the ITS and thus one copy of the nuclear rRNA genes. Therefore, two types of ITS sequences derived from a specimen would indicate that the patient is infected by two types of P. carinii f. sp. hominis.