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31.
32.
Bilateral abscessed orchiepididymitis associated with sepsis caused by Veillonella parvula and Clostridium perfringens: case report and review of the literature. 下载免费PDF全文
P M Arrosagaray C Salas M Morales M Correas J M Barros M L Cordon 《Journal of clinical microbiology》1987,25(8):1579-1580
Veillonella species is a gram-negative coccus which is part of the anaerobic normal flora in the oral cavity, small intestine, upper respiratory tract, vagina, and urinary tract. The role that this organism plays in infection is not well known, and it is generally associated with other bacteria. We present a case of bilateral abscessed orchiepididymitis associated with septicemia due to Veillonella parvula and, later, to Clostridium perfringens, with the development of severe renal insufficiency and septic shock, which resolved favorably with antibiotic therapy, treatment of shock, and hyperbaric oxygen therapy. In reviewing the literature, we have not found any other case of sepsis due to Veillonella sp. associated with urological disorders. 相似文献
33.
A M Yamamoto C Mura M G Morales O Bernard R Krishnamoorthy F Alvarez 《Clinical and experimental immunology》1992,87(2):251-255
Cytochrome P450 IID6 is an autoantigen recognized by the sera of children affected with a subtype of autoimmune hepatitis. It was hypothesized that a mutation in the CYP2D6 gene could explain the autoimmune response in these patients. To examine this question, genomic DNA from peripheral lymphocytes (n = 9) and liver (n = 1) of 10 patients with anti-LKM-1 antibody was analysed by Southern blot for genetic association studies between a particular CYP2D6 haplotype and autoimmune hepatitis. In addition, a region of CYP2D6, from the same genomic DNA, was amplified by polymerase chain reaction (PCR) and digested by BstNI, in a search for the most prevalent 29B mutation, described in subjects who do not express the P450 IID6. Total RNA and proteins, prepared from the liver of an anti-LKM-1+ patient, were analysed by Northern and Western (immunoblot) blots respectively. Our results do not reveal any major structural change in the DNA of this patient at the CYP2D6 locus that could explain their autoimmune response. Corroborating this observation, no changes were noted either in P450 IID6 mRNA size or in the corresponding protein. However, these data do not exclude the possibility of subtle changes in the protein due to point mutations in critical regions that might trigger an autoimmune response. 相似文献
34.
35.
Septal unit activity and hippocampal EEG during the sleep-wakefulness cycle of the rat 总被引:1,自引:0,他引:1
The functional relationship between septal unit activity and hippocampal EEG was studied during the sleep-wakefulness cycle in chronically implanted unrestrained rats. Results were statistically analyzed in order to obtain the time interval and auto and crosscorrelation histograms. During REM sleep and restless wakefulness the hippocampal EEG showed a theta rhythm of 4–8 cps and the septal unit activity was characterized by the presence of rhythmic bursts with a frequency in every single instance similar to that of the hippocampus. The septal units showed a bimodal time interval histogram. Their autocorrelation histogram exhibited a sinusoidal pattern of decreasing amplitude. The crosscorrelation histogram of septal units and the hippocampal EEG also showed a sinusoidal pattern suggestive of the functional relationship between both neural structures. During slow wave sleep and quiet wakefulness there was a disappearance of the hippocampal theta rhythm and rhythmic septal unit bursts. The second mode was missing in the time interval histogram and the auto and crosscorrelation histograms showed an irregular pattern. It is concluded that medial septal nucleus and hippocampal temporal patterns of activity are similar during REM sleep and restless wakefulness. 相似文献
36.
Comparison of BACTEC MYCO/F LYTIC and WAMPOLE ISOLATOR 10 (lysis-centrifugation) systems for detection of bacteremia, mycobacteremia, and fungemia in a developing country 总被引:2,自引:0,他引:2 下载免费PDF全文
Archibald LK McDonald LC Addison RM McKnight C Byrne T Dobbie H Nwanyanwu O Kazembe P Reller LB Jarvis WR 《Journal of clinical microbiology》2000,38(8):2994-2997
In less-developed countries, studies of bloodstream infections (BSI) have been hindered because of the difficulty and costs of culturing blood for bacteria, mycobacteria, and fungi. During two study periods (study period I [1997] and study period II [1998]), we cultured blood from patients in Malawi by using the BACTEC MYCO/F LYTIC (MFL), ISOLATOR 10 (Isolator), Septi-Chek AFB (SC-AFB), and Septi-Chek bacterial (SC-B) systems. During study period I, blood was inoculated at 5 ml into an MFL bottle, 10 ml into an Isolator tube for lysis and centrifugation, and 10 ml into an SC-B bottle. Next, 0.5-ml aliquots of Isolator concentrate were inoculated into an SC-AFB bottle and onto Middlebrook 7H11 agar slants, chocolate agar slants, and Inhibitory Mold Agar (IMA) slants. During study period II, the SC-B and chocolate agar cultures were discontinued. MFL growth was detected by fluorescence caused by shining UV light (lambda = 365 nm) onto the indicator on the bottom of the bottle. During study period I, 251 blood cultures yielded 44 bacterial isolates. For bacteremia, the MFL was similar to the Isolator concentrate on chocolate agar (34 of 44 versus 27 of 44; P, not significant [NS]), but more sensitive than the SC-B bottle (34 of 44 versus 24 of 44; P = 0.05). For both study periods combined, 486 blood cultures yielded 37 mycobacterial and 13 fungal isolates. For mycobacteremia, the sensitivities of the MFL and Isolator concentrate in the SC-AFB bottle were similar (30 of 37 versus 29 of 37; P, NS); the MFL bottle was more sensitive than the concentrate on Middlebrook agar (30 of 37 versus 15 of 37; P = 0.002). For fungemia, the MFL bottle was as sensitive as the SC-B bottle or Isolator concentrate on chocolate agar or IMA slants. We conclude that the MFL bottle, inoculated with just 5 ml of blood and examined under UV light, provides a sensitive and uncomplicated method for comprehensive detection of BSI in less-developed countries. 相似文献
37.
Cryptosporidium parvum-specific CD4 Th1 cells from sensitized donors responding to both fractionated and recombinant antigenic proteins 总被引:1,自引:0,他引:1 下载免费PDF全文
Gomez Morales MA Mele R Ludovisi A Bruschi F Tosini F Riganò R Pozio E 《Infection and immunity》2004,72(3):1306-1310
T-cell-mediated immunity plays a central role in the host response to Cryptosporidium parvum. Human T-cell clones (TCC) were isolated from peripheral blood mononuclear cells of five healthy donors with prior cryptosporidiosis by use of a C. parvum crude extract, two antigen fractions obtained by ion-exchange chromatography (IEC1 and IEC2), and two recombinant peptides (SA35 and SA40) from C. parvum sporozoites. The T-cell lines derived from the one recently infected donor had a higher proportion (26 to 38%) of T cells exhibiting the gamma/delta T-cell receptor (gamma/delta-TCR) than those from donors who had recovered from cryptosporidiosis several years earlier, suggesting that the gamma/delta T-cell population is involved in the early stage of the infection. The specific TCC had the alpha/beta-TCR, had the phenotype CD45RO(+) CD4(+) CD8(-), and were characterized by either hyperproduction of gamma interferon (IFN-gamma) alone, with a Th1 profile, or IFN-gamma hyperproduction together with interleukin-4 (IL-4) or IL-5 production, with a Th0 profile. SA35, SA40, IEC1, and IEC2 may be considered good targets of the cellular response against C. parvum and may play a role in maintaining the T-cell-mediated memory response to this parasite. Furthermore, the SA35 and SA40 peptides may be regarded as immunodominant antigens involved in the maintenance of the T-cell response in healthy C. parvum-sensitized persons. 相似文献
38.
39.
Enhanced inhibitory avoidance learning prevents the memory-impairing effects of post-training hippocampal inactivation 总被引:1,自引:0,他引:1
Quiroz C Martínez I Quirarte GL Morales T Díaz-Cintra S Prado-Alcalá RA 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2003,153(3):400-402
Rats were trained on an inhibitory avoidance task to study the effects of post-training administration of tetrodotoxin (TTX, which temporarily inactivates neural activity) on memory consolidation. During training, independent groups of rats received either a mild foot shock (0.8 mA) or a stronger (1.0 mA) foot shock. TTX was administered bilaterally into the dorsal hippocampus immediately after training, and memory of the task was measured 48 h later. We corroborated the typical amnesic effect of intrahippocampal infusions of TTX in those rats trained with the mild-intensity foot shock. More importantly, with the stronger foot shock, the same treatment was ineffective in producing amnesia. These results suggest that, after an enhanced learning experience, other brain regions are also activated, which may compensate for the amnesic effect of TTX infusions into the hippocampus.Due to an error in the citation line, this revised PDF (published in December 2003) deviates from the printed version, and is the correct and authoritative version of the paper. 相似文献
40.
J R Regueiro P Perez-Aeiego P Aparicio C Martinez P Morales A Arnaiz-Villena 《European journal of immunology》1990,20(11):2411-2416
B lymphocytes require appropriate T lymphocyte cooperation to synthesize immunoglobulins (Ig). Such interaction presumably takes place after engagement of the T cell receptor (TcR) by antigen. The present work addresses B lymphocyte function (and phenotype) in a novel type of immunodeficiency which is characterized by a TcR expression defect. In contrast to expectations, the two affected siblings that were studied displayed normal in vivo antibody responses to both endogenous and exogenous protein antigens. However, they showed impaired responses to certain polysaccharide antigens together with a selective IgG2 deficiency. These results suggest that some polysaccharide responses may be more T cell dependent than previously suspected, and support the notion that T cell dysfunctions (of this or other kind), rather than Ig gene deletions, may be the molecular basis of certain IgG2 deficiencies. To rule out a concomitant gross B cell dysfunction in these individuals, B lymphocyte phenotype and function were assayed in vitro, and found to be normal. A T cell line derived from one of the siblings displayed an abnormal TcR on the cell surface, but it showed several normal TcR-mediated functions. This suggests that the low number of peripheral T lymphocytes that have been found to express low TcR levels in these immunodeficiencies may be operational, and supplying sufficient "help" for the observed normal antibody responses to all tested protein, but not polysaccharide, antigens. 相似文献