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11.
12.
Temperature-mediated heteroduplex analysis for detection of pncA mutations associated with pyrazinamide resistance and differentiation between Mycobacterium tuberculosis and Mycobacterium bovis by denaturing high- performance liquid chromatography
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Mohamed AM Bastola DR Morlock GP Cooksey RC Hinrichs SH 《Journal of clinical microbiology》2004,42(3):1016-1023
The goal of this study was to apply temperature-mediated heteroduplex analysis using denaturing high-performance liquid chromatography to identify pyrazinamide (PZA) resistance in Mycobacterium tuberculosis isolates and simultaneously differentiate between M. tuberculosis and Mycobacterium bovis. Features that contributed to an optimal assay included the use of two different reference probes for the pncA gene targets from wild-type M. tuberculosis and wild-type M. bovis, optimization of the column temperature, increasing the starting concentration of the elution buffer, and reducing the rate of elution buffer increase (slope). A total of 69 strains were studied, including 48 wild-type M. tuberculosis strains (13 were PZA-resistant strains) and 21 M. bovis strains (8 were BCG strains). In all isolates tested, wild-type M. tuberculosis generated a single-peak pattern when mixed with the M. tuberculosis probe and a double-peak pattern with the M. bovis probe. In contrast, all M. bovis isolates generated a double-peak pattern when mixed with the M. tuberculosis probe and a single-peak pattern with the M. bovis probe. PZA-resistant mutant M. tuberculosis isolates generated characteristic patterns that were easily distinguishable from both wild-type M. tuberculosis and M. bovis isolates. Chromatographic patterns generated by the two reference probes allowed the rapid detection of PZA resistance with the simultaneous ability to distinguish between M. tuberculosis and M. bovis. This approach may allow the detection of drug resistance-associated mutations, with potential application to clinical and epidemiological aspects of tuberculosis control. 相似文献
13.
Identification of Aspergillus species using internal transcribed spacer regions 1 and 2 总被引:15,自引:0,他引:15
Aspergillus species are the most frequent cause of invasive mold infections in immunocompromised patients. Although over 180 species are found within the genus, 3 species, Aspergillus flavus, A. fumigatus, and A. terreus, account for most cases of invasive aspergillosis (IA), with A. nidulans, A. niger, and A. ustus being rare causes of IA. The ability to distinguish between the various clinically relevant Aspergillus species may have diagnostic value, as certain species are associated with higher mortality and increased virulence and vary in their resistance to antifungal therapy. A method to identify Aspergillus at the species level and differentiate it from other true pathogenic and opportunistic molds was developed using the 18S and 28S rRNA genes for primer binding sites. The contiguous internal transcribed spacer (ITS) region, ITS 1-5.8S-ITS 2, from referenced strains and clinical isolates of aspergilli and other fungi were amplified, sequenced, and compared with non-reference strain sequences in GenBank. ITS amplicons from Aspergillus species ranged in size from 565 to 613 bp. Comparison of reference strains and GenBank sequences demonstrated that both ITS 1 and ITS 2 regions were needed for accurate identification of Aspergillus at the species level. Intraspecies variation among clinical isolates and reference strains was minimal. Sixteen other pathogenic molds demonstrated less than 89% similarity with Aspergillus ITS 1 and 2 sequences. A blind study of 11 clinical isolates was performed, and each was correctly identified. Clinical application of this approach may allow for earlier diagnosis and selection of effective antifungal agents for patients with IA. 相似文献
14.
Fugger EF; Black SH; Keyvanfar K; Schulman JD 《Human reproduction (Oxford, England)》1998,13(9):2367-2370
The world's first deliveries of normal babies after use of flow cytometric
separated human sperm cells (MicroSort) for preconception gender selection
are reported. Offspring were of the desired female gender in 92.9% of the
pregnancies. Most of these pregnancies and births were achieved after
simple intrauterine insemination.
相似文献
15.
Bedside to bench and back again: how animal models are guiding the development of new immunotherapies for cancer 总被引:3,自引:0,他引:3
Finkelstein SE Heimann DM Klebanoff CA Antony PA Gattinoni L Hinrichs CS Hwang LN Palmer DC Spiess PJ Surman DR Wrzesiniski C Yu Z Rosenberg SA Restifo NP 《Journal of leukocyte biology》2004,76(2):333-337
Immunotherapy using adoptive cell transfer is a promising approach that can result in the regression of bulky, invasive cancer in some patients. However, currently available therapies remain less successful than desired. To study the mechanisms of action and possible improvements in cell-transfer therapies, we use a murine model system with analogous components to the treatment of patients. T cell receptor transgenic CD8+ T cells (pmel-1) specifically recognizing the melanocyte differentiation antigen gp100 are adoptively transferred into lympho-depleted mice bearing large, established, 14-day subcutaneous B16 melanoma (0.5-1 cm in diameter) on the day of treatment. Adoptive cell transfer in combination with interleukin interleukin-2 or interleukin-15 cytokine administration and vaccination using an altered form of the target antigen, gp100, can result in the complete and durable regression of large tumor burdens. Complete responders frequently develop autoimmunity with vitiligo at the former tumor site that often spreads to involve the whole coat. These findings have important implications for the design of immunotherapy trials in humans. 相似文献
16.
AbstractThere are many useful medical treatment devices today, which are indispensable in health care. However, in some emergency situations and in prehospital care mobile, easy-to-use devices could further improve the patient-centred care. For example, a mobile, easy-to-use home-monitoring EEG-system would be useful for monitoring diseases like epilepsy and for treating diseases like attention deficit disorder (ADHD) using biofeedback. Such a device should be equipped with the ability to start self-performed by user recordings and provide high signal quality, while having an affordable price. Here, we used in-ear-EEG technology and state of the art electronic components to develop such a system. This paper presents a portable, all-in-one EEG-system, capable to record biosignals on the external ear. An amplifier was developed with ADS1299 and optimised to be coupled with a smartphone. The system has a low price and at the same time provides high signal quality, has very effective common-mode-rejection, performs a fast cold start and shows low power consumptions which ensures a long time of operation. The system is easy to use and could be self-mounted and controlled by unskilled users as well. Results of test measurements are compared to a conventional EEG-System and show comparable records results quality. 相似文献
17.
The differentiation of basic emotions by means of EEG power spectra has been discussed extensively by Machleidt et al. (1989). The present contribution concentrates on the interhemispheric coupling of different EEG-signals as depending on the modulation of these emotions. In the first part the estimation and interpretation of squared coherence spectra is outlined. Results from this technique are presented in the following section. Intention, Aggression and Joy are mainly characterized by an increase of alpha-coherence, whereas a decrease is seen for Anxiety and Sorrow. These effects showed a widespread distribution. 相似文献
18.
Mahadevaiah SK; Odorisio T; Elliott DJ; Rattigan A; Szot M; Laval SH; Washburn LL; McCarrey JR; Cattanach BM; Lovell-Badge R; Burgoyne PS 《Human molecular genetics》1998,7(4):715-727
An RNA-binding motif (RBM) gene family has been identified on the human Y
chromosome that maps to the same deletion interval as the 'azoospermia
factor' (AZF). We have identified the homologous gene family (Rbm) on the
mouse Y with a view to investigating the proposal that this gene family
plays a role in spermatogenesis. At least 25 and probably >50 copies of
Rbm are present on the mouse Y chromosome short arm located between Sry and
the centromere. As in the human, a role in spermatogenesis is indicated by
a germ cell-specific pattern of expression in the testis, but there are
distinct differences in the pattern of expression between the two species.
Mice carrying the deletion Yd1, that maps to the proximal Y short arm, are
female due to a position effect resulting in non-expression of Sry ;
sex-reversing such mice with an Sry transgene produces males with a high
incidence of abnormal sperm, making this the third deletion interval on the
mouse Y that affects some aspect of spermatogenesis. Most of the copies of
Rbm map to this deletion interval, and the Yd1males have markedly reduced
Rbm expression, suggesting that RBM deficiency may be responsible for, or
contribute to, the abnormal sperm development. In man, deletion of the
functional copies of RBM is associated with meiotic arrest rather than
sperm anomalies; however, the different effects of deletion are consistent
with the differences in expression between the two species.
相似文献
19.
The psychomotor, cognitive, and mood effects of orally administered diazepam and placebo were measured over 3.5 h. A total of 120 volunteers were assigned to 12 groups of 10 each, representing the combination of four treatments (placebo, 0.1, 0.2, and 0.3 mg/kg diazepam) and three testing sessions (7 AM, 1 PM, and 7 PM). A variety of cognitive tasks, tapping and postural stability tests, and a mood evaluation scale were used. Psychomotor and cognitive functions showed consistent dose-response effects, while for subjective evaluations, the only effect of dose level was in the duration of sedation. The pattern of impairment of cognitive functions suggests that the drug affects speed rather than accuracy, and it primarily blocks acquisition of new information or skills. Use of repeated testing may therefore be necessary to detect subtle drug effects. Subjects reported no tranquilization, which suggests that the anxiolytic action of the drug cannot be studied in healthy volunteers. There was no circadian influence on the actions of the drug. 相似文献
20.
Objective To construct a eukaryotic expression system with pcDNA3-PfCSP/Hela for the Circ umsporozoite protein (CSP) gene of Plasmodium falciparum (P.falciparum), t o observe the immune responses in BALB/c mice induced by the expressed proteins .Methods The recombinant plasmid pcDNA3-PfCSP was transformed into the Hela cell line. The expressed protein was isolated and analyzed by using SDS-PAGE and used for immunization of BALB/c mice by subcutaneous, intravenous, and intraperitone al adminstration.Enzyme-linked immunosorbent assay(ELISA), Dot-ELISA, Wester n blot, T lymphocyte proliferation test, natural killer cell(NKC) activity assay , and CD4(+) and CD8(+) T cell detection were used for observation of humoral an d cellular immune responses.Results Immune sera strongly reacted with the expressed protein, antibody titer was up to 1∶6400 as detected by ELISA.Western blot analysis revealed a specific b and at 38.3 Kda.When the spleen cells of normal and immunized BALB/c mice we re specifically stimulated with expressed protein, the optical densities were 0 .12±0.03 and 0.34±0.04, respectively.The latter were significantly highe r than the former (P<0.01).We used the MTT colorimetric assay to measure NKC activity of mice spleen.The results showed that the NKC activity of immuni zed BALB/c mice was remarkably higher than that of the controls (P<0.05). CD4(+) and CD8(+) T cells were detected by using monoclonal antibody immunofluor escence methods.The results showed that the percentage of CD4(+) and CD8(+) T cells of immunized group were significantly higher than that of control group ( P<0.05).Conclusions The humoral and cell-mediated immune responses and elevated NKC activity to pr oducts made with a eukaryotic expression system could be specifically detected i n BALB/c mice.These findings indicate that the expressed protein could enhance the immune function in mice. 相似文献