Characterization of erythromycin-resistant Streptococcus pneumoniae in Korea, and In Vitro activity of telithromycin against erythromycin-resistant Streptococcus pneumoniae

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.     

PD-1-Expressing SARS-CoV-2-Specific CD8+ T Cells Are Not Exhausted,but Functional in Patients with COVID-19

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TGFβ1基因对血管内皮细胞细胞外基质表达及与基质黏附的影响

了解TGFβ1基因对血管内皮细胞表达细胞外基质蛋白及与基质黏附力的影响。用DOTAP脂质体转染p MAMneo TGFβ1于原代培养的脐静脉内皮细胞,经G4 18筛选,TGFβ1表达经免疫荧光鉴定。Western blot确定 型胶原、纤黏连蛋白的表达,微管吸吮系统确定内皮细胞与基质的黏附力。结果表明生理情况下的内皮细胞能表达少量的TGFβ1及胶原、纤黏连蛋白。经G4 18筛选,外源性TGFβ1在血管内皮细胞中稳定表达,能显著提高胶原、纤黏连蛋白纤维的表达及细胞与基质的黏附。说明TGFβ1在血管组织工程中促进内皮细胞的黏附具有一定的应用价值。     

多发性骨髓瘤的个体型阳性细胞检查及意义

近年来抗个体型抗体(antiidiotypeantibodies,抗Id抗体)的理论研究及应用有了迅速地发展,已成为免疫学研究中活跃领域之一。个体型是指在同一个体内,不同的抗体形成细胞所产生的免疫球蛋白(Ig)有各自不同的抗原特异性。决定个体型抗原特异性的部位在抗体可变区的超可变区,是针对超可变区某些抗原决定簇的抗体。在     

NF-κB的活性和iNOS基因表达在低氧性肺动脉高压中的变化

目的：探讨NF-κB的活性及iNOS基因表达在低氧性肺动脉高压（HPH）发病过程中的变化。方法：复制低氧性肺动脉高压大鼠模型，用免疫组化、原位杂交、半定量逆转录-聚合酶链式反应（RT-PCR）和Western blot等方法进行检测。结果：iNOS mRNA在腺泡内肺动脉（IAPA）的表达，低氧28 d（H28d）组染色强于正常（N）组、低氧5 d（H5d）组和低氧14 d（H14d）组。半定量RT-PCR证实低氧肺组织iNOS mRNA含量在H28d组分别是N组、H5d组和H14d组的2.1倍、1.9倍和1.8倍。H28d组肺组织NF-κB的核染色增多，I-κBα的含量在N组、H5d组和H14d组分别是H28d组的2.7倍、2.8倍和2.5倍。结论：在HPH中NF-κB的激活可能与低氧肺血管构建及iNOS mRNA的表达有关。     

The ultrastructure of hybrid acute leukemia: a study of 15 cases

The objective of this study was to investigate the ultrastructural characteristics of hybrid acute leukemia (HAL). Fifteen cases of HAL were studied by transmission electron microscopy (TEM), focusing on organelles and myeloperoxidase (MPO) reaction of leukemic cells. By TEM, 5 out 15 cases of HAL were consistent with immunophenotyping (3 cases of biphenotypic type, and 2 cases of biclonal type with granulocytes and lymphocytes); 2 cases were suspected as HAL. On other hand, 5 cases of HAL were assigned to ALL, and 2 cases were misinterpreted as M5a and 1 as M4b. Most of the blast cells of biphenotypic HAL showed lymphoid features, except some cases containing MPO positive granules in blasts, while a few cases exhibited monocytic or nonspecific features. TEM offers advantages in the diagnosis of biclonal type HAL and biphenotypic HAL positive for MPO. However, it is difficult to differentiate MPO-negative cases of biphenotypic HAL from ALL and a few cases may be misinterpreted as M5 by TEM.     

Effect of ketamine on apoptosis by energy deprivation in astroglioma cells using flow cytometry system

Apoptosis is a programmed, physiologic mode of cell death that plays an important role in tissue homeostasis. As for the central nervous system, ischemic insults can induce pathophysiologic cascade of apoptosis in neurophils. Impairment of astrocyte functions during brain ischemia can critically influence neuron survival by neuronglia interactions. We aimed to elucidate the protective effect of ketamine on apoptosis by energy deprivation in astrocytes. Ischemic insults was induced with iodoacetate/ carbonylcyanide m-chlorophenylhydrazone (IAA/CCCP) 1.5 mM/20 microm or 150 microm/2 microm for 1 hr in the HTB-15 and CRL-1690 astrocytoma cells. Then these cells were reperfused with normal media or ketamine (0.1 mM) containing media for 1 hr or 24 hr. FITC-annexin-V staining and propidium iodide binding were determined by using flow cytometry. Cell size and granularity were measured by forward and side light scattering properties of flow cytometry system, respectively. An addition of ketamine during reperfusion increased the proportion of viable cells. Ketamine alleviated cell shrinkage and increased granularity during the early period, and ameliorated cell swelling during the late reperfusion period. Ketamine may have a valuable effect on amelioration of early and late apoptosis in the astrocytoma cells, even though the exact mechanism remains to be verified.     

Infestation of sand lizards (<Emphasis Type="Italic">Lacerta agilis</Emphasis>) resident in the Northeastern Poland by <Emphasis Type="Italic">Ixodes ricinus</Emphasis> (L.) ticks and their infection with <Emphasis Type="Italic">Borrelia burgdorferi</Emphasis> sensu lato

Sand lizards (Lacerta agilis) were trapped and examined for ticks from May to September in 2002 and 2003 in Northeastern Poland. A total of 233 Ixodes ricinus (L.) ticks (76 larvae and 157 nymphs) was found on 31 of 235 captured lizards (13.2%). The tick infestation is relatively low compared to that of mammals and passerine birds from the same area (Siński et al. 2006, Gryczyńska et al. 2002). Tick infestation depended on the month of capture, being the highest in spring. In autumn no ticks were recorded on any of the captured lizards. The oldest lizards carried the highest number of ticks but no differences related to sex of the host were found. All the collected ticks were analysed by PCR for the presence of Borrelia burgdorferi sensu lato, the etiological agents of Lyme disease. Spirochetes were detected in 11 out of 233 (4.7%) ticks tested. Genetic analysis confirmed that the spirochetes are members of the Borrelia afzelii, B. garinii and B. burgdorferi sensu stricto genospecies. Mixed infection were not detected. The prevalence of infection was analysed in relation to months of the capture, age and sex of the lizards, but differences were not statistically significant. The obtained results suggest that lizards are probably not B. burgdorferi reservoirs, but further studies are required to confirm this.     

Wilms tumor in patients with osteopathia striata with cranial sclerosis

Germline pathogenic variants in AMER1 cause osteopathia striata with cranial sclerosis (OSCS: OMIM 300373), an X-linked sclerosing bone disorder. Female heterozygotes exhibit metaphyseal striations in long bones, macrocephaly, cleft palate, and, occasionally, learning disability. Male hemizygotes typically manifest the condition as fetal or neonatal death. Somatically acquired variants in AMER1 are found in neoplastic tissue in 15–30% of patients with Wilms tumor; however, to date, only one individual with OSCS has been reported with a Wilms tumor. Here we present four cases of Wilms tumor in unrelated individuals with OSCS, including the single previously published case. We also report the first case of bilateral Wilms tumor in a patient with OSCS. Tumor tissue analysis showed no clear pattern of histological subtypes. In Beckwith–Wiedemann syndrome, which has a known predisposition to Wilms tumor development, clinical protocols have been developed for tumor surveillance. In the absence of further evidence, we propose a similar protocol for patients with OSCS to be instituted as an initial precautionary approach to tumor surveillance. Further evidence is needed to refine this protocol and to evaluate the possibility of development of other neoplasms later in life, in patients with OSCS.Subject terms: Genetics, Clinical genetics, Disease genetics     

Interaction between KIR3DL1 and HLA-B*57 supertype alleles influences the progression of HIV-1 infection in a Zambian population

KIR and HLA loci are both highly polymorphic, and some HLA class 1 products bind and trigger cell-surface receptors specified by KIR genes. We examined whether KIR genes act in concert with HLA-B locus to control HIV-1 infection in a sample of Zambian patients. DNA samples from 88 Zambian patients with HIV-1 were examined. Patients were classified as either slow progressors (SP; n = 54) or rapid progressors (RP; n = 34) to AIDS. All were typed for HLA-B and KIR genes. Our results reveal an association between B*57 supertype (B*57s, which includes B*57 and B*58 alleles) and delayed progression to AIDS (p = 0.0007 by pc = 0.015; OR = 5.25). We also observed an increase incidence of Bw4-I80 in patients with slow progression (p = 0.001 by pc = 0.003, OR = 5). This increase was found to be secondary to B*57s. The presence of both KIR3DL1 and B*57S has a significant effect on progression to AIDS (p = 0.0008; OR = 5.61). B*57s genotypes with another HLA-B allele different from those in the trans position, which also had a specificity different to Bw4-I80 (Bw4-T80 or Bw6), was also greater in the SP than in the RP group (p = 0.00003; OR = 10.11). The presence of the inhibitory allele KIR3DL1 in combination with the HLA-B*57s alleles that contain the Bw4-I80 epitope, has a highly protective effect against progression to AIDS in Zambian patients.