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61.
62.
Comparative evaluation of the new version of the INNO-LiPA Mycobacteria and genotype Mycobacterium assays for identification of Mycobacterium species from MB/BacT liquid cultures artificially inoculated with Mycobacterial strains 总被引:2,自引:0,他引:2
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Padilla E González V Manterola JM Pérez A Quesada MD Gordillo S Vilaplana C Pallarés MA Molinos S Sánchez MD Ausina V 《Journal of clinical microbiology》2004,42(7):3083-3088
The performance of two DNA line probe assays, a new version of INNO-LiPA Mycobacteria (Innogenetics, Ghent, Belgium) and the GenoType Mycobacterium (Hain Diagnostika, Nehren, Germany), were evaluated for identification of mycobacterial species isolated from liquid cultures. Both tests are based on a PCR technique and designed for simultaneous identification of different mycobacterial species by reverse hybridization and line probe technology. The INNO-LiPA Mycobacteria v2 targeting the 16S-23S rRNA gene spacer region was developed for the simultaneous identification of 16 different mycobacterial species. The GenoType Mycobacterium, which targets the 23S rRNA gene, allows simultaneous identification of 13 mycobacterial species. Both tests were evaluated on 110 mycobacterial strains belonging to 22 different mycobacterial species (20 reference strains, 83 clinical strains, and 4 Mycobacterium kansasii strains isolated from tap water) that were previously inoculated into MB/BacT bottles. The sensitivity of both methods, defined as the number of positive results obtained with the Mycobacterium genus probe together with an interpretable result on the number of samples tested was 110 of 110 (100%) for INNO-LiPA and 102 of 110 (92.7%) for GenoType. For samples with interpretable results, INNO-LiPA was able to correctly identify 109 of 110 samples (99.1%), whereas the GenoType correctly identified 100 of 102 samples (98.0%). Both tests were easy to perform, rapid, and reliable when applied to mycobacterial identification directly from MB/BacT bottles. 相似文献
63.
Lucia MB Rutella S Leone G Larocca LM Vella S Cauda R 《Journal of acquired immune deficiency syndromes (1999)》2002,30(4):369-378
P-glycoprotein (P-gp) transports a wide range of structurally unrelated drugs, such as HIV protease inhibitors (PIs) and cytotoxic compounds such as anthracyclines. Because modification of P-gp phenotype and function is an important underlying mechanism of drug interactions, the current study was conducted in order to evaluate whether highly active antiretroviral therapy (HAART), HIV plasma viral load (VL), or cancer chemotherapy may induce in vivo changes of P-gp phenotype in peripheral blood mononuclear cells (PBMCs) from HIV-infected treatment-naive and -experienced subjects at different stages of HIV infection and/or disease, including patients with HIV-associated Kaposi sarcoma (KS). Our results show that neither HAART nor HIV VL, nor the stage of HIV infection and/or disease, significantly alter P-gp expression on PBMCs. In particular, surface P-gp expression is expressed at low levels by T-cell subsets, B cells, and NK cells, whereas almost all monocytes are double positive and these results are not modified by HIV PI-containing regimens. By contrast, a significant phenotype modification is detected in PBMCs from AIDS/KS patients after challenge with the liposomal formulation of the anthracycline doxorubicin (L-DOX) with the higher expression reached 24 hours after the end of the drug infusion. In addition, accumulation of L-DOX is unaffected by P-gp-mediated drug efflux as documented by in vitro experiments, in sharp contrast to the kinetic of free DOX, based on HIV PI blockade experiments. Finally, P-gp expression was found in KS spindle cells from HIV-infected treatment-naive AIDS/KS patients. We conclude that P-gp phenotype in PBMCs and specific subsets is not altered by HAART and/or HIV, whereas a significant increase is induced by specific anticancer drugs such as L-DOX. Moreover, HIV PIs possess an inhibitory effect on P-gp function that may improve DOX sensitivity in KS spindle cells. 相似文献
64.
Alen Hajnal Sergio Fonseca Jeffrey M. Kinsella-Shaw Paula Silva Claudia Carello M.T. Turvey 《Neuroscience letters》2007
Nonvisual perceptions of a wielded object's spatial properties are based on the quantities expressing the object's mass distribution, quantities that are invariant during the wielding. The mechanoreceptors underlying the kind of haptic perception involved in wielding – referred to as effortful, kinesthetic, or dynamic touch – are those embedded in the muscles, tendons, and ligaments. The present experiment's focus was the selectivity of this muscle-based form of haptic perception. For an occluded rod grasped by the hand at some intermediate position along its length, participants can attend to and report selectively the rod's full length, its partial lengths (fore or aft of the hand), and the position of the grip. The present experiment evaluated whether participants could similarly attend selectively when wielding by foot. For a given rod attached to and wielded by foot or attached to (i.e. grasped) and wielded by hand, participants reported (by magnitude production) the rod's whole length or fractional length leftward of the point of attachment. On measures of mean perceived length, accuracy, and reliability, the degree of differentiation of partial from full extent achieved by means of the foot matched that achieved by means of the hand. Despite their neural, anatomical, and experiential differences, the lower and upper limbs seem to abide by the same principles of selective muscle-based perception and seem to express this perceptual function with equal facility. 相似文献
65.
Sergio Daga Chiara Fallerini Margherita Baldassarri Francesca Fava Floriana Valentino Gabriella Doddato Elisa Benetti Simone Furini Annarita Giliberti Rossella Tita Sara Amitrano Mirella Bruttini Ilaria Meloni Anna Maria Pinto Francesco Raimondi Alessandra Stella Filippo Biscarini Nicola Picchiotti Marco Gori Pietro Pinoli Stefano Ceri Maurizio Sanarico Francis P. Crawley Giovanni Birolo GEN-COVID Multicenter Study Alessandra Renieri Francesca Mari Elisa Frullanti 《European journal of human genetics : EJHG》2021,29(5):745
Within the GEN-COVID Multicenter Study, biospecimens from more than 1000 SARS-CoV-2 positive individuals have thus far been collected in the GEN-COVID Biobank (GCB). Sample types include whole blood, plasma, serum, leukocytes, and DNA. The GCB links samples to detailed clinical data available in the GEN-COVID Patient Registry (GCPR). It includes hospitalized patients (74.25%), broken down into intubated, treated by CPAP-biPAP, treated with O2 supplementation, and without respiratory support (9.5%, 18.4%, 31.55% and 14.8, respectively); and non-hospitalized subjects (25.75%), either pauci- or asymptomatic. More than 150 clinical patient-level data fields have been collected and binarized for further statistics according to the organs/systems primarily affected by COVID-19: heart, liver, pancreas, kidney, chemosensors, innate or adaptive immunity, and clotting system. Hierarchical clustering analysis identified five main clinical categories: (1) severe multisystemic failure with either thromboembolic or pancreatic variant; (2) cytokine storm type, either severe with liver involvement or moderate; (3) moderate heart type, either with or without liver damage; (4) moderate multisystemic involvement, either with or without liver damage; (5) mild, either with or without hyposmia. GCB and GCPR are further linked to the GCGDR, which includes data from whole-exome sequencing and high-density SNP genotyping. The data are available for sharing through the Network for Italian Genomes, found within the COVID-19 dedicated section. The study objective is to systematize this comprehensive data collection and begin identifying multi-organ involvement in COVID-19, defining genetic parameters for infection susceptibility within the population, and mapping genetically COVID-19 severity and clinical complexity among patients.Subject terms: Genetics research, Viral infection 相似文献
66.
Bruna Velasques Sergio Machado Cláudio Elidio Portella Julio Guilherme Silva Luis F.H. Basile Mauricio Cagy Roberto Piedade Pedro Ribeiro 《Neuroscience letters》2007
The present experiment aimed at investigating electrophysiologic changes observed as beta band asymmetry, by Quantitative Electroencephalography (qEEG), when individuals performed a reaching motor task (catching a ball in free fall). The sample was composed of 23 healthy individuals, of both sexes, with ages varying between 25 and 40 years old. All the subjects were right handed. A two-way ANOVA was applied for the statistical analysis, to verify the interaction between task moment (i.e., 2 s before and 2 s after ball's fall) and electrode (i.e., frontal, central and temporal regions). The first analysis compared electrodes placed over the somatosensory cortex. Central sites (C3–C4) were compared with temporal regions (T3–T4). The results showed a main effect for moment and position. The second analysis was focused over the premotor cortex, which was represented by the electrodes placed on the frontal sites (F3–F4 versus F7–F8), and a main effect was observed for position. Taken together, these results show a pattern of asymmetry in the somatosensory cortex, associated with a preparatory mechanism when individuals have to catch an object during free fall. With respect to task moment, after the ball's fall, the asymmetry was reduced. Moreover, the difference in asymmetry between the observed regions were related to a supposed specialization of areas (i.e., temporal and central). The temporal region was associated with cognitive processes involved in the motor action (i.e., explicit knowledge). On the other hand, the central sites were related to the motor control mechanisms per se (i.e., implicit knowledge). The premotor cortex, represented by two frontal regions (i.e., F3–F4 versus F7–F8), showed a decrease on neural activity in the contralateral hemisphere (i.e., to the right hand). This result is in agreement with other experiments suggesting a participation of the frontal cortex in the planning of the apprehension task. This sensorimotor paradigm may contribute to the repertoire of tasks used to study clinical conditions such as depression, alzheimer and Parkinson diseases. 相似文献
67.
Taenia crassiceps can naturally and experimentally infect rodents in which they reproduce by budding. Differences in the susceptibility to T. crassiceps cysticercosis were found between two BALB/c substrains: BALB/cAnN (susceptible) and BALB/cJ (resistant). In chimeric mice, resistance was transferred to susceptible mice with bone marrow cells from the resistant mice, which argues in favor of an immune mediation of the resistant phenotype. To further explore the immune response that could underlie these differences in susceptibility, the specific cellular immune response elicited by the parasite was explored in both substrains. An increased proliferative response and IL-2 levels were induced by cysticercal antigens only in splenocytes from resistant mice. A decrease in the percentage of CD4(+) (11.1%), CD8(+) (17.5%) was found in splenocytes from susceptible BALB/cAnN mice. A study of the TCRV beta repertoire revealed a significant decrease in V beta 2 in both CD4(+) and CD8(+) splenocytes only in the susceptible BALB/cAnN strain. 相似文献
68.
Barbaro G Grisorio B Fruttaldo L Bacca D Babudieri S Torre D Francavilla R Rizzo G Belloni G Lucchini A Annese M Matarazzo F Hazra C Barbarini G 《BioDrugs : clinical immunotherapeutics, biopharmaceuticals and gene therapy》2003,17(6):433-439
Background: The differential tolerability profile of various interferon (IFN)-α preparations used in combination with ribavirin for the treatment of chronic hepatitis C needs to be elucidated. Approximately 8% of patients receiving recombinant IFNα-2b plus ribavirin discontinue treatment because of adverse events. Human leucocyte IFNα is deemed to have a better safety profile than recombinant IFNα. We therefore compared the safety profile and efficacy of ribavirin combined with leucocyte IFNα or with recombinant IFNα-2b in treatment-naive patients with chronic hepatitis C. Study design: We randomised 423 patients to either leucocyte IFNα 3MU three times weekly plus ribavirin (210 patients) or the same dose of recombinant IFNα-2b plus ribavirin (213 patients). Patients were treated for 24 weeks and followed-up for a further 48 weeks. The primary endpoint was the safety profile of the two therapies; the secondary endpoint was the rate of sustained response. Results: In patients receiving leucocyte IFNα, the total number of adverse events was lower than in the group receiving recombinant IFNα (259 vs 441 patients), and the percentage of patients discontinuing treatment because of adverse events or laboratory abnormalities was significantly reduced (4% vs 11%; p = 0.013). Sustained response was observed in 47% of patients receiving leucocyte IFNα plus ribavirin and in 44% of patients receiving IFNα-2b plus ribavirin. Conclusions: Both therapeutic regimens were effective in inducing a sustained response in naive patients. However, the safety profile of leucocyte IFNα plus ribavirin was more favourable than that observed with the administration of recombinant IFNα-2b plus ribavirin, suggesting that leucocyte IFNα may be an alternative option in patients with reduced tolerability to other IFNs. 相似文献
69.
Arancha C Ruíz-Llorente S Cascón A Osorio A Martínez-Delgado B Benítez J Robledo M 《Journal of human genetics》2002,47(4):190-195
Until now, the study of the multiple endocrine neoplasia type 1 (MEN1) gene in patients suspected of having the disease was expensive and laborious due to the large size of the gene. We have
optimized the conformation-sensitive gel electrophoresis (CSGE) technique to analyze by four rather simple multiplex PCR reactions,
and a single electrophoresis run, the entire coding region of the MEN1 gene, plus the exon–intron boundaries. This improvement of the CSGE technique was confirmed as an effective procedure for
screening for the MEN1 gene by detecting ten previously known MEN1 gene mutations and four polymorphisms. The MEN1 gene of 12 patients with unknown mutations was then screened, and an abnormal CSGE profile was identified in 10/12 cases.
Subsequent DNA sequencing demonstrated 3 of them to be novel mutations (E45K, 4479delACAG, 6073insC) and 7 to have been previously
reported; in the remaining 2 patients, we confirmed the absence of any alteration of the coding sequence of MEN1. Mutation screening of the MEN1 gene using CSGE was demonstrated to be a fast, simple, and inexpensive method to study patients suspected of having MEN1
disease.
Received: November 29, 2001 / Accepted: January 28, 2002 相似文献
70.
The pituitary-adrenal responsiveness to a mild stressor was assessed in rats that were deprived of paradoxical sleep (PS) and in controls that were not deprived. Animals were either individually- or group-deprived for 96 h and hormone levels were assessed at 0, 5, 20 or 60 min after a saline injection+novelty and compared with rats which were not deprived. Both types of PS deprivation resulted in elevated adrenocorticotropin levels at 0 min, which peaked at 5 min in all animals. Individually-deprived rats exhibited the highest corticosterone (CORT) levels at 0 min. Peak levels were higher and occurred earlier in PS-deprived than in control rats (5 vs. 20 min, respectively). At 20 min, CORT levels had already returned to unstressed levels in PS-deprived rats, but not in control rats. These data indicate that PS deprivation induces facilitation of the adrenocortical response to a mild stressor, but do not suggest that PS deprivation changes the negative feedback sensitivity to CORT. 相似文献