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991.
Leptospiral antigens in the liver of experimentally infected guinea pig and their relation to the morphogenesis of liver damage. 总被引:3,自引:0,他引:3
V A Alves L C Gayotto T De Brito R T Santos A Wakamatsu M R Vianna E E Sakata 《Experimental and toxicologic pathology》1992,44(7):425-434
In order to investigate the morphogenes of experimental leptospirosis by morphologic and immunohistologic methods, 24 guinea-pigs were inoculated intraperitoneally with L. interrogans serogroup Icterohaemorrhagiae. They were divided in 6 groups, sacrificed from the 1st to the 6th day of infection. Semiquantitative analyses of histopathological liver lesions were performed in 1 micron sections of tissue embedded in glycol-methacrylate. The distribution of leptospiral antigen (L. Ag) and its glycolipoprotein (GLP) was demonstrated by peroxidase-antiperoxidase on paraffin embedded tissue. Significant lesions appeared at the 4th day of infection, progressing to a peak on the 6th day. Inflammation was associated with injury of the portal triad. Liver cells showed either swelling or acidophilic degeneration and necrosis, together with loss of cell cohesion, leading to disarray of liver cell plates. Mitochondria were found progressively enlarged and irregularly distributed. L. Ag expression was parallel to the morphological changes. Portal distribution was significant at the 4th day and on later stages centrilobular localization became predominant. Spiral forms suggestive of intact leptospires were initially found but, chiefly at the 6th day, L. Ag was seen in granules, probably resulting from phagocytosis. GLP staining was similar to granular L. Ag in morphology, and distribution. Cytokeratin condensation was seen in liver cells with acidophilic necrosis and was marked in areas of disorganization of cell plates. Our findings lead us to hypothesize a direct leptospiral cytotoxic effect on endothelial and on liver-cell membranes. At first, leptospires themselves would induce subcellular changes acting mainly on membrane permeability. Afterwards, their granular forms, including GLP, would act as adjuvant factors. These findings demonstrate that the disarray of liver cell plates at the late phase of the disease is genuine. 相似文献
992.
Ferrazzani S Merola A De Carolis S Carducci B Paradisi G Caruso A 《Human reproduction (Oxford, England)》2000,15(1):210-217
The aim of this study was to verify whether twin pregnancies complicated by pre-eclampsia were associated with a higher rate of inter-twin weight discordance or an increased prevalence of small for gestational age (SGA) neonates than in normotensive twin pregnancies. A 17 year retrospective study was undertaken by examining 76 twin pregnancies complicated by pre-eclampsia and comparing them with 400 normotensive twin pregnancies. The case notes were reviewed in reference to birth weight differences, birth order, pregnancy outcome and inter-twin birth weight discordance. Statistical analyses were performed with t-test, contingency tables, regression curves, rank sum test and non-parametric survival plots. Power analysis was also carried out. Pre-eclamptic twin pregnancies were delivered at similar weeks of gestation to normotensive. They resulted in a smaller size for the second twin the earlier the delivery week, while in normotensive twin pregnancies no significant difference occurred at any week. Twin pregnancies complicated by pre-eclampsia showed higher rates of SGA neonates among second twins than those with normal pressure. The >25% discordance was associated with lower gestational age at delivery in each group [mean (range) 33 weeks (27-38) versus 37 (29-41), P < 0.005 pre-eclampsia and 35 weeks (25-41) versus 38 (25-42), P < 0.001 normotensive]. In pre-eclampsia the concomitant occurrence of SGA second twin and the discordance >25% was associated with shorter gestation while the presence of SGA second twin alone was not. 相似文献
993.
La Porta CA 《International journal of molecular medicine》2000,5(5):467-471
Melanoma metastasis is almost uniformly fatal. The identification of signal transduction as crucial effectors for tumorigenesis suggests modalities of gene therapy as well as design of specific drugs. the possible use of nPKCdelta as a therapeutic target is reviewed and discussed. Motivated by recent results, we propose a model in which nPKCdelta modulates melanin synthesis as well as metastasis. 相似文献
994.
De Carlo A Roda R Rossi MR Ceruti S Ghinelli F Libanore M 《Le infezioni in medicina : rivista periodica di eziologia, epidemiologia, diagnostica, clinica e terapia delle patologie infettive》2000,8(3):167-172
Objectives: To study etiological, epidemiological and clinical features of 97 cases of acute meningitis. Methods: Ninety-seven cases of acute meningitis were examined in adult HIV-negative patients admitted to the Infectious Diseases Unit of the Azienda Ospedale-Universita S. Anna in Ferrara. Demographic, etiological, epidemiological and clinical data were analyzed. Results: All cases were divided into two groups according to the macroscopic aspect of cerebrospinal fluid (CSF): purulent CSF (50 cases) or non-purulent CSF (47 cases). Purulent CSF meningitis more frequently affected male patients (64% vs 47%) and older patients (average 52 vs 44 years). The main epidemiological features in both groups were underlying bacterial diseases (i.e. otomastoiditis and/or sinusitis in 50% of pneumococcal meningitis) and iatrogenic immunodeficiency. From a clinical point of view the following alterations in the state of consciousness (stupor, confusion and coma) were most frequently found in purulent meningitis. The following non purulent forms of meningitis were diagnosed: 5 tubercular, 3 viral infections, 2 by Listeria monocytogenes, 1 by Entoameba histolytica, 1 by Cryptococcus neoformans and 35 (74,4%) unknown causes. Purulent meningitis were: 20 (40%) Streptococcus pneumoniae, 10 Neisseria meningitidis, 3 Staphylococcus aureus, 2 Escherichia coli, 1 Haemophilus influenzae and 1 Pseudomonas aeruginosa; 13 cases were unidentified. From 1989 to 1993 and from 1994-98 both groups of meningitis increased; respectively from 17 to 30 cases for non-purulent meningitis and from 18 to 32 cases for purulent meningitis. Meningitis due to Streptococcus pneumoniae increased from 27.7% to 46.8% during the period 1994-98. Conclusions: The study shows the high incidence of pneumococcal meningitis, during 1994-98, because a large number of patients with sinusitis and otomastoiditis were observed. The incidence of meningococcal meningitis appears stable. These data confirm the importance of timely diagnosis and correct therapy for such infections with reserved prognosis. 相似文献
995.
In October 1992, a new disease characterised by acute death in racing pigeons of all ages was noted among the Belgian pigeon population. Clinical symptoms were minimal since affected birds usually died within 24 h. Mortality in pigeon lofts usually amounted to 30%. The most typical necropsy finding was a yellow, pale and swollen liver. Histological and cytological examinations revealed extensive focal or diffuse hepatic necrosis and the presence of eosinophilic or amphophilic nuclear inclusion bodies. This hepatic necrosis of viral origin was diagnosed in 151 (15%) of 988 submissions of pigeons at our Institute in 1993 and 1994. Oral and intramuscular inoculation of pigeons with a bacteria-free homogenate prepared from the liver of pigeons that died from the disease did not result in clinical signs. However, when similar inoculations were done in pigeons previously treated orally with dexamethasone, pigeons died very suddenly within 4-5 days of inoculation. Necropsy findings in experimentally infected pigeons were identical to those observed in naturally occurring cases. Electron microscopic examination of the liver of inoculated pigeons showed the presence of numerous adenovirus-like particles inside nuclei of hepatocytes. The virus could not be cultured in the allantoic cavity or on the chorioallantoic membrane of embryonated chicken eggs. Clinical signs and lesions described here are clearly different from adenovirus enteritis in young pigeons abundantly described since 1976. 相似文献
996.
A. Kentos S. Motte C. Nonhoff F. Jacobs J. M. De Smet E. Serruys J. P. Thys 《European journal of clinical microbiology & infectious diseases》1994,13(2):142-145
A case of monomicrobial endocarditis due toPrevotella bivia in a 60-year-old man without previous cardiac lesions is reported. The extremely indolent course with multiple systemic emboli as the only clinical manifestation occurring at least seven months before diagnosis and the persistently negative blood cultures were remarkable features of this case. The incidence, clinical characteristics, treatment and outcome of published cases of infective endocarditis due to anaerobic bacteria are briefly reviewed. 相似文献
997.
Susana Camacho Maria Del Valle Ostos José Ignacio Llorente Ana Sanz Manuel García Alberto Domezain Ramón Carmona 《Anatomical record (Hoboken, N.J. : 2007)》2007,290(9):1178-1189
Ampullary organs of Acipenser naccarii sturgeons were examined by optical and electronic microscopy (transmission electron microscopy and scanning electron microscopy) from hatching until 1 month later when the juvenile phase is completely established. It was observed that, when A. naccarii begins to feed actively, the ultrastructural characteristics of ampullary organs already correspond to those of adult animals. These organs may, therefore, be functional and, together with taste buds, facilitate food search after exhaustion of yolk sac food reserves. Mature ampullary organs of A. naccarii are formed by an ampulla that communicates with the exterior by means of a short channel. These ampullae correspond to the sensory portion of these receptors and are formed by two cell types: receptor cells and support cells. Receptor cells present a kinocilium on their free surface and establish ribbon synapses with axon nerve endings that arise from the underlying conjunctive tissue. Support cells enclose receptor cells, bear stereocilia and occasional cilia, and are of a secretory nature. The mucus associated with ampullary organs mainly comprises neutral mucopolysaccharides, whereas mucopolysaccharides are usually acid in other fish groups. Anat Rec, 290:1178–1189, 2007. © 2007 Wiley‐Liss, Inc. 相似文献
998.
Anna Gillio-Tos Laura De Marco Valeria Ghisetti Peter J F Snijders Nereo Segnan Guglielmo Ronco Franco Merletti 《Journal of clinical virology》2006,36(2):126-132
BACKGROUND: Infection with human papillomavirus (HPV) is a necessary step in the progression to cervical cancer. Many methods for HPV testing are currently available, most developed to detect pools of HPV types. OBJECTIVES: To evaluate the HPV typing by molecular methods and to compare commercial kits with an established laboratory method. STUDY DESIGN: Eighty-four cervical samples found to be positive for HPV DNA by GP5+/6+-polymerase chain reaction-enzyme immunoassay-reverse line blotting (PCR-EIA-RLB) were re-tested with two commercial methods, INNO-LiPA and Amplisense HPV typing, able to identify the HPV type predicted by PCR-EIA-RLB in 76 and 67 samples, respectively. RESULTS: The INNO-LiPA assay revealed HPV DNA in 75/76 samples (98.7%; 95% CI, 0.93-0.99) that would contain HPV types identifiable by this assay. The Amplisense HPV assay revealed HPV DNA in 58/67 samples (86.6%; 95% CI, 0.76-0.93) containing HPV types detectable by this assay. For samples with a single infection, the unweighted kappa for concordance of HPV typing was 0.87 (95% CI, 0.78-0.97) for PCR-EIA-RLB versus INNO-LiPA, 0.94 (95% CI, 0.87-0.99) for INNO-LiPA versus Amplisense HPV, and 0.82 (95% CI, 0.70-0.94) for PCR-EIA-RLB versus Amplisense HPV typing. PCR-EIA-RLB revealed 12 multiple infections, INNO-LiPA revealed 14, and Amplisense HPV revealed 5. The agreement among tests for samples with multiple infections was lower, giving kappa values of 0.44 (95% CI, 0.18-0.70) for PCR-EIA-RLB versus INNO-LiPA, 0.52 (95% CI, 0.19-0.85) for PCR-EIA-RLB versus Amplisense HPV and 0.43 (95% CI, 0.12-0.74) for INNO-LiPA versus Amplisense HPV. CONCLUSIONS: In HPV-positive samples, the agreement among tests for HPV typing was high for single infections but markedly lower for infections with multiple HPV types. 相似文献
999.
Philippe Hup Cline Rouveirol Isabel Brito Pierre Neuvial Philippe La Rosa Eric Viara Nicolas Stransky Gaëlle Pierron Elodie Mani Caroline Brennetot Isabelle Jannoueix Nadge Gruel Alain Aurias Olivier Delattre Franois Radvanyi Emmanuel Barillot 《European journal of medical genetics》2005,48(4):467-468