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91.
Kim NJ Park SJ Choi SH Lee MS Choo EJ Kwak YG Woo JH Ryu J Jeong JY Kim YS 《Microbial drug resistance (Larchmont, N.Y.)》2005,11(3):260-265
To characterize the phenotypes and genotypes of erythromycin-resistant clinical isolates of Streptococcus pneumoniae in Korea and to evaluate the in vitro activity of telithromycin against these erythromycin-resistant isolates, we tested a total of 676 isolates of S. pneumoniae collected from 1997 to 2002 in a tertiary hospital in Seoul, Republic of Korea. MICs for erythromycin and telithromycin were determined by the agar dilution method. The macrolide resistance phenotypes of erythromycin-resistant isolates were determined by the erythromycin- clindamycin-rokitamycin triple disk (ECRTD) and MIC induction tests, whereas their macrolide resistance genotypes were determined by PCR for the erm(B), erm(A), subclass erm(TR), and mef genes. To discriminate between mef(A) and mef(E), PCR-restriction fragment length polymorphism (RFLP) analyses were performed. Of the 676 S. pneumoniae isolates, 459 (67.9%) were resistant to erythromycin. Of the 459 erythromycin-resistant isolates, 343 (74.7%) were assigned to the cMLS phenotype, 48 (10.4%) to the iMcLS phenotype, 4 (0.9%) to the iMLS phenotype, and 64 (14.0%) to the M phenotype. The erm(B) gene was detected in 251 (54.6%) isolates, the mef gene was detected in 64 (14.0%), and both the erm(B) and mef genes were detected in 144 (31.4%) isolates. All of the mef genes detected were identified as mef(E). Of the 459 erythromycin- resistant isolates, all but one were susceptible to telithromycin. The MIC(50)/MIC(90) to telithromycin of isolates carrying erm(B), mef(E), and both genes was 0.06/0.5 microg/ml, 0.03/0.125 microg/ml, and 0.5/1.0 microg/ml, respectively. Although the MICs of telithromycin for the erythromycin-resistant isolates varied according to genotype, telithromycin was very active against these erythromycin-resistant S. pneumoniae. 相似文献
92.
Jang AS Choi IS Lee S Nam HS Kweon SS Son MH Lee JH Park SW Kim DJ Uh ST Kim YH Park CS 《Journal of Korean medical science》2004,19(2):214-217
Passive smoking is a major cause of respiratory morbidity, and is associated with increased bronchial responsiveness in children. To evaluate the effect of smoking by a parent on asthma symptoms, atopy, and airway hyperresponsiveness (AHR), we conducted a cross-sectional survey of 503 schoolchildren that involved questionnaires, spirometry, allergy testing, and a bronchial challenge test. If the PC20 methacholine was less than 16 mg/mL, the subject was considered to have AHR. The prevalence of a parent who smoked was 68.7%. The prevalence of AHR was 45.0%. The sensitization rate to common inhalant allergens was 32.6%. Nasal symptoms such as rhinorrhea, sneezing, nasal itching, and nasal obstruction were present in 42.7%. Asthma symptoms such as cough and wheezing were present in 55.4%. The asthma symptoms were significantly more prevalent in children who had a parent who smoked than in those whose parents did not. The nasal symptoms, atopy, and AHR did not differ according to whether a parent smoked. In a multiple logistic regression model, the asthma symptoms and atopy were independently associated with AHR, when adjusted for confounding variables. Passive smoking contributed to asthma symptoms in schoolchildren and was not an independent risk factor of airway hyperresponsiveness in an epidemiological survey. 相似文献
93.
A discrete-time kinetic model for chemotherapy was developed to deal with the effects of antitumor drugs on the cell cycle
and proliferation kinetics of experimental tumor cell populations in which cell kinetic responses of chemotherapy are represented
in terms of perturbation of cell kinetic parameters—cell age, cell size and DNA content distributions. The time-course behavior
of these cell kinetic parameters was predicted by solving the discrete-time state equations which characterize the dynamics
of tumor-drug interactions. The amount of antitumor drug administered was expressed to be the control function of the state
equations and the transition matrix representing two modes of drug action, namely, cell kill and progression delay or accumulation
of cells due to drug, was derived. The performance of the model, assessed by examining the effects of cell cycle stage-specific
agents such as cytosine arabinoside on spontaneous AKR leukemia, compared favorably with experimental data. Utilizing an optimization
scheme in engineering systems studies, an analytical method is described for optimizing the regimen of drug administration
so as to maximize the effectiveness of drug dosage schedules and minimize the use of toxic amounts of the drug. The superiority
of the schedule designed by an optimization scheme was evident at the termination of therapy, although the schedule designed
by experimental trials reduced the number of surviving tumor cells more effectively than the one designed by an optimization
scheme during the earlier therapy period. In the model, the proposed schedule will function more effectively for the entire
therapy period when additional parameters of drug characteristics, such as the toxicity to the host and drug resistance, are
encompassed. 相似文献
94.
Microsatellite alterations in hepatocellular carcinoma and intrahepatic cholangiocarcinoma 总被引:1,自引:0,他引:1
A series of 20 hepatocellular carcinomas and 8 intrahepatic cholangiocarcinomas was screened from the Korean population for microsatellite alterations, including a loss of heterozygosity and replication errors using nine microsatellite markers containing several genes. The microsatellite results and our previous comparative genomic hybridization results of two tumors were compared at each locus, and the correlations between these and clinicopathologic variables were examined. The most characteristic findings were found at 13q. Replication errors were prevalent at D13S160 (13q21.2 approximately q31) and D13S292(13q12). The incidence of loss of heterozygosity, however, was higher at D13S153 (13q14.1 approximately q14.3) and D13S265(13q31 approximately q32). In contrast, there were higher deletion frequencies observed in hepatocellular carcinoma (HCC) and higher amplification frequencies observed in intrahepatic cholangiocarcinoma at 13q in our previous comparative genomic hybridization (CGH) study. Higher frequencies of replication errors were observed at D16S408 (13q12 approximately q21) and D16S504(13q23 approximately q24) in the HCC. This study found that significant differences in the patterns of genetic instability of microsatellites were dependent on the chromosomal loci. It is believed that certain genes at altered CGH regions, which are relevant to the development and/or progression of these cancers, are activated by different mutation mechanisms. 相似文献
95.
Joon Young Song Seok Hoon Ha Sae Yoon Kee Hye Won Jeong Hee Jin Cheong Woo Joo Kim 《Journal of clinical virology》2007,38(2):149-152
BACKGROUND: Influenza vaccination is the primary method for preventing influenza and its severe complications. Healthcare workers (HCWs) are one of the priority groups for the influenza vaccination. OBJECTIVES: To determine whether healthy HCWs, who were vaccinated with the same subtype for the two previous years, could be given less priority for influenza immunization under the vaccine shortage. STUDY DESIGN: We measured hemagglutination-inhibition antibody titers from sequential serum samples in 50 pre-immune subjects and 50 age-matched vaccine-naive subjects: immediately prior to the administration of the vaccine, 4-6 weeks, and 6 months after the vaccination. RESULTS: Prevaccination titers were maintained above protective level and high protection rates were observed for all three strains in pre-immune subjects: A/H1N1, A/H3N2, and B strains. As for the sequential changes, the protection rates for all three strains still remained above 70% until 6 months following the vaccination. CONCLUSION: Skipping influenza vaccination for a year could be considered in healthy pre-immune HCWs under the epidemic of the same subtype as two previous years. 相似文献
96.
Kim CK Kim SW Park CS Kim BI Kang H Koh YY 《The Journal of allergy and clinical immunology》2003,112(1):64-71
BACKGROUND: The pathogenetic basis for the relationship between acute bronchiolitis and asthma has not yet been completely elucidated. OBJECTIVE: The aim of this study was to compare these 2 diseases in terms of their patterns of airway cytokine response (T(H)1 or T(H)2). METHODS: By using a bronchoalveolar lavage (BAL) technique, this study investigated the cytokine levels of BAL fluid in children with acute asthma who had no identifiable respiratory syncytial virus (RSV) infection (n = 18) and in infants with acute bronchiolitis caused by RSV (n = 22). Comparisons were made with normal control subjects (n = 14). IFN-gamma (T(H)1) and IL-4 and IL-5 (T(H)2) levels were measured in concentrated BAL fluids by means of ELISA. RESULTS: The IL-5 level (P <.001) and IL-5/IFN-gamma ratio (P <.001) were significantly increased in the asthmatic group with no identifiable RSV infection and in the RSV-induced bronchiolitis group compared with values in the control group. When infants in the bronchiolitis group were divided into eosinophil-positive and eosinophil-negative subgroups, the eosinophil-positive subgroup had significantly increased IL-5 levels (P <.001) and IL-5/IFN-gamma ratios (P <.01) compared with those in the control group, but similar cytokine responses were not induced in the eosinophil-negative subgroup. The percentage of BAL eosinophils correlated significantly with levels of BAL IL-5 in both the asthma group (r = 0.80, P =.000) and the bronchiolitis group (r = 0.82, P =.000). CONCLUSIONS: These findings suggest that a subgroup of the RSV-induced bronchiolitis group results in a T(H)2-type response, and this could provide a valuable framework to explain the link between RSV-induced bronchiolitis and asthma. 相似文献
97.
Hematological indices were determined in a group of 427 elderly Chinese subjects over 60 years old; reference ranges were established after excluding subjects with hemoglobinopathies or diseases giving rise to anemia and those with values less or greater than 3 SD from the mean. The values were similar to those for elderly Caucasians. All the red cell indices were significantly higher in men than women, possibly reflecting the influence of androgens on bone marrow function. Previously reported age-related decline in hemoglobin, red cell count and hematocrit from studies of all age groups was not seen in men or women above age 60 years, but a fall in platelet count with age, which had not been previously reported, was observed. There were no age-related changes in any other indices. Reference ranges were lower for Hb, MCV, and MCH in men and women, compared to those derived from a study of Chinese of all age groups. The prevalence of anemia due to disease and hemoglobinpathies in this population was 6.4% in men and 6.3% in women. 相似文献
98.
Eduardo C. Salido Merry B. Passage Pauline H. Yen Larry J. Shapiro T. K. Mohandas 《Somatic Cell and Molecular Genetics》1993,19(1):65-71
The expression of mouseZfx, Rps4, Ube1x, andXist was evaluated in hamstermouse somatic cell hybrids containing either an active or an inactive mouse X chromosome using polymerase chain reaction of reverse transcribed RNA (RT-PCR). The results showed thatZfx, Rps4, andUbe1x are expressed exclusively from the active mouse X, whileXist is expressed exclusively from the inactive X. These findings confirm the pattern of X inactivation for these mouse genes reported previously based on expression in somatic tissues of F1 females from interspecific crosses. These results demonstrate the existence of differences between human and mouse X inactivation, as the corresponding human genes,ZFX, RPS4X, andUBE1 escape X inactivation. 相似文献
99.
No recombinant protein is available for serodiagnosis or skin test in the diagnosis of melioidosis. This report describes the cloning of the malE gene, which encodes an immunogenic protein of Burkholderia pseudomallei. Bi-directional DNA sequencing of malE revealed that the gene contained a single open reading frame encoding 416 amino acid residues with a predicted molecular mass of 44.4 kDa. BLAST analysis showed that the putative protein encoded by malE is homologous to the maltose-binding protein (MBP) of other bacteria. It has 48% and 63% amino acid identity and similarity with the MBP of Brucella abortus, and malE complementation assay showed that it partially complemented the function of the MBP of Escherichia coli. Several highly conserved regions among the MBP of B. pseudomallei, Br. abortus, Salmonella enterica serotype Typhimurium, E. coli and Enterobacter aerogenes were observed. These regions represent signatures A, B, C, D and F identified in the MBP of E. coli. Further sequence analysis revealed that the first 24 amino acid residues of the MBP of B. pseudomallei probably represent the N-terminal signal peptide of the protein. Similar to the signal peptide of the MBP of E. coli, Ent. aerogenes and S. Typhimurium, the MBP of B. pseudomallei contains two basic residues in the first eight amino acids, followed by a hydrophobic core, with the last three amino acids in the signal peptide being Ala-Gln-Ala, conforming to the consensus sequence Ala-X-Ala at positions -3 to -1 relative to the site of proteolytic cleavage for recognition by signal peptidase I. Further studies on serodiagnosis of melioidosis with recombinant MBP should be performed. 相似文献
100.
alpha(v)beta(3) Integrin in central nervous system tumors 总被引:1,自引:0,他引:1
Lim M Guccione S Haddix T Sims L Cheshier S Chu P Vogel H Harsh G 《Human pathology》2005,36(6):665-669
alpha(v)beta(3) Is an integrin specifically expressed in endothelial cells of newly forming blood vessels. Integrin-mediated angiogenesis is hypothesized to play a central role in the development and the progression of central nervous system neoplasms. Accordingly, it is considered a potential target for antiangiogenic therapy. In the current study, we compare the expression of alpha(v)beta(3) in ependymomas, oligodendrogliomas, pilocytic astrocytomas, medulloblastomas, and vestibular schwannomas (acoustic neuromas). Samples of 5 tumors of each of the 5 tumor types were harvested surgically and frozen. After the pathological diagnosis was confirmed, immunohistochemistry was performed using an anti- alpha(v)beta(3) monoclonal antibody (LM609). The expression of alpha(v)beta(3) was assessed using a 4-tiered (0-3) grading scheme reflecting the percentage of positively staining vessels. All vestibular schwannomas demonstrated strong (grade 3) alpha(v)beta(3) expression. The expression was uniformly prominent in Antoni B regions of the tumors. Of 5 ependymomas, 4 demonstrated uniformly strong alpha(v)beta(3). Oligodendrogliomas, medulloblastomas, and pilocytic astrocytomas demonstrated more variable alpha(v)beta(3). alpha(v)beta(3) may contribute significantly to angiogenesis in vestibular schwannomas and ependymomas. Despite the high vascular density of oligodendrogliomas, pilocytic astrocytomas, and medulloblastomas, these tumors had variable moderate alpha(v)beta(3) expression. This discrepancy suggests temporal and/or regional variability in the angiogenesis in these types of tumor. This study provides the first demonstration of alpha(v)beta(3) expression in vestibular schwannomas, medulloblastomas, and pilocytic astrocytomas. 相似文献