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H Lepidi

Publications and source records attributed to H Lepidi.

At least 37 records · Page 2Linked to original sources
PubMed2000

Repeated pregnancies in BALB/c mice infected with Coxiella burnetii cause disseminated infection, resulting in stillbirth and endocarditis.

Q fever is a widespread zoonosis caused by the obligate intracellular bacterium Coxiella burnetii. Although this highly virulent organism is most concentrated in mammals during parturition, there are few reports on the manifestations of perinatal Q fever in the human and animal host. The affinity of C. burnetii to pregnancy and its abortifacient potential were investigated in a murine animal model. Intraperitoneal infection of female BALB/c mice with C. burnetii, followed by repeated pregnancies over a 2-year period, resulted in persistent infection associated with abortion and perinatal death, with a statistically significant decrease in viable offspring. In addition, endocarditis occurred in 2 of the adult animals, and C. burnetii antigen and DNA were detected in their heart valves. Taken together, these results demonstrate the abortifacient potential of C. burnetii and the increased risk of persistent infection and endocarditis in pregnant mice, probably related to a decline in cellular immunity during pregnancy.

Animals↗
PubMed2000

Quantitative analysis of valvular lesions during Bartonella endocarditis.

Cardiac valve pathology was evaluated in 15 patients with confirmed diagnosis of Bartonella endocarditis. Ten were infected by Bartonella quintana and 5 by Bartonella henselae. Histologic features of these cases, including fibrosis, calcification, vegetation, pattern of inflammation, and vascularization, were compared with those of valves from 25 cases of non-Bartonella endocarditis as controls using a computerized quantitative image analysis. Pathologic and immunohistologic testing for localization of Bartonella species in resected valves included Warthin-Starry stain and polyclonal antibody-based immunodetection. Compared with other cases of infective endocarditis, cases of Bartonella endocarditis are more fibrotic and calcified, less vascularized, with less extensive vegetation and chronic inflammation. These pathologic changes are suggestive of a prolonged infection. Warthin-Starry stain and immunohistologic testing demonstrated the presence of the organism, respectively, in 11 and 10 of the 13 tested valves. Results of both staining methods showed microorganisms in extracellular locations and in regions unaccompanied by inflammation. Pathology and immunohistology may contribute to the etiologic diagnosis of Bartonella endocarditis when serology and molecular techniques are not available.

Adult↗
PubMed2000

Comparative pathology, and immunohistology associated with clinical illness after Ehrlichia phagocytophila-group infections.

The Ehrlichia phagocytophila-group also includes E. equi and the human granulocytic ehrlichiosis (HGE) agent that are probably a single species. Disease is mild to severe illness in ruminants, horses, and humans, but the comparative pathology and ehrlichial distribution in tissues is poorly described. We compared pathology and ehrlichial distribution in humans with HGE, horses with E. equi infection, and a sheep with E. phagocytophila infection. Frequent findings included splenic lymphoid depletion, small macrophage aggregates and apoptoses in liver, and paracortical hyperplasia in lymph nodes. Bone marrow was normocellular or hypercellular. Only the spleen was frequently infected; other organs with infected cells included lung, liver, heart, and kidney, but lesions were present in lung and liver only. Most infected cells were neutrophils. Ehrlichia phagocytophila-group infections are associated with moderate tissue damage. While the pathogenesis of granulocytic ehrlichiosis is not clear, pathologic studies suggest that the process is initiated by ehrlichia-infected cells but may result from host-mediated injury and immunosuppression.

Adult↗
PubMed1999

Local expression of monocyte chemoattractant protein-1 (MCP-1) in idiopathic inflammatory myopathies.

The idiopathic inflammatory myopathies (IIM), including dermatomyositis (DM), polymyositis (PM), and inclusion body myositis (IBM), are a group of autoimmune diseases characterized by the recruitment of lymphocytes and monocytes to the site of affection. The mechanism for recruitment of these cells likely involves chemokines. The monocyte chemoattractant protein-1 (MCP-1), a chemoattractant to T lymphocytes and monocytes, may play an important role in the pathogenesis of IIM. Frozen muscular tissues were obtained from eight cases of DM, five PM, and four IBM. We investigated the MCP-1 expression by the reverse transcription-PCR technique, immunohistochemistry and in situ hybridization. MCP-1 mRNA was markedly expressed in all the IIM cases. Greater amounts of MCP-1 mRNA were observed in DM, and in situ hybridization showed MCP-1 mRNA accumulation in perivascular mononuclear cells. Immunohistochemistry showed MCP-1 expression in vessels (endothelial cells and walls of veins and arteries) in all IIM cases. Very few mononuclear cells in DM perivascular infiltrates expressed MCP-1, whereas in PM and IBM, it was strongly expressed by mononuclear cells partially invading non-necrotic muscle fibers. These findings suggest that MCP-1 can contribute to the inflammatory response by attracting monocytes and T lymphocytes to sites of cell-mediated immune injury. The morphological characteristics and distribution of positive cells indicate that macrophages, lymphocytes, and endothelial cells previously reported to produce MCP-1, contribute to its production in IIM lesions.

Adult↗
PubMed1999

[Expression of adhesion molecules in idiopathic inflammatory myopathies. Immunohistochemical study of 17 cases].

We investigated the immunohistochemical expression of endothelial cell adhesion molecules in 17 cases of idiopathic inflammatory myopathies. The present study revealed: 1) a constitutive expression of ICAM-1, ICAM-2 and PECAM-1, but not VCAM-1, LFA-3 and E-selectin, on endothelial cells in normal muscles; 2) a modification of cell adhesion molecules expression in idiopathic inflammatory myopathies with an increased expression of the expressed molecules constitutively; an expression of LFA-3 and VCAM-1 on capillary endothelial cells in polymyositis/inclusion body myositis, these molecules being only observed on endothelial cells of some arterioles in dermatomyositis; 3) an expression of all these molecules on inflammatory cells in inflammatory myopathies. In dermatomyositis, the expression of ICAM-1 and VCAM-1, predominated on mononuclear cells located near vessels. In polymyositis/inclusion body myositis, a strong expression of ICAM-1, VCAM-1 and LFA-3 was present on inflammatory cells invading non necrotic muscle fibers; 4) absence of E-selectin on endothelial and inflammatory cells in all cases.

Cell Adhesion Molecules↗
PubMed1998

Bacillary angiomatosis in immunocompromised patients.

OBJECTIVES: To report seven cases of bacillary angiomatosis; to evaluate the most useful diagnostic tools; to analyse the clinical and epidemiological features associated with Bartonella quintana or Bartonella henselae infections. DESIGN: Clinical, diagnostic and epidemiological evaluation of 37 speciated bacillary angiomatosis cases in the literature, including the seven patients in our study. METHODS: Pathological examination of tissue samples, including Warthin-Starry staining and immunohistology; titre of antibodies to Bartonella sp.; detection of Bartonella sp. in blood and biopsy materials by culture or PCR; and statistical analysis of clinical and epidemiological features associated with B. quintana or B. henselae bacillary angiomatosis cases. RESULTS: Seven immunocompromised patients (six with AIDS and one patient with acute leukaemia) had bacillary angiomatosis confirmed by histology. B. quintana was cultured in three patients, whereas B. henselae DNA was amplified by PCR in the remaining four patients. Serum from only one patient reacted with Bartonella antigens. Amongst the 14 B. quintana and 23 B. henselae bacillary angiomatosis cases now reported in the literature, lymphadenopathies were significantly more frequent in B. henselae-infected patients, and neurological disorders of the central nervous system in B. quintana-infected patients. Risk factors were contact with cats, and homelessness or poor socioeconomic status in B. henselae and B. quintana bacillary angiomatosis cases, respectively. CONCLUSIONS: Although diagnosis of bacillary angiomatosis often remains solely based upon histology, culture or PCR-based methods are useful for the detection of Bartonella sp., and allow identification of the species involved, which is necessary to further characterize clinical and epidemiological features associated with B. quintana or B. henselae infections.

AIDS-Related Opportunistic Infections↗
PubMed1998

Hidden chromosome abnormalities in a primary central nervous system lymphoma detected by multicolor spectral karyotyping.

Cytogenetic analysis provides important information for diagnosis and prognosis in some tumors. But karyotype analysis can be difficult in some cases, because metaphase chromosomes are contracted. New techniques, such as fluorescence in situ hybridization and, more recently, spectral karyotyping, or SKY, based on the hybridization of 24 fluorescently labeled chromosome painting probes, allow the detection and identification of complex chromosomal rearrangements. We report here a case of primary central nervous system lymphoma in which chromosomal rearrangements and marker chromosomes not identified by a routine cytogenetic technique were clarified by SKY. This shows the value of the SKY technique in the cytogenetic diagnosis of tumors.

Aged↗
PubMed1998

Local expression of cytokines in idiopathic inflammatory myopathies.

The idiopathic inflammatory myopathies (IIM), including dermatomyositis (DM), polymyositis (PM), and inclusion body myositis (IBM), are regarded as autoimmune diseases. They are characterized by chronic lymphocytic and macrophagic infiltration in muscle tissue. Of particular importance in understanding the immune response to IIM is the specific pattern of locally produced cytokines. Frozen muscle tissues from IIM (5 DM, 3 PM, and 1 IBM) were used to investigate the cytokine responses. The RT-PCR technique was instrumental to determine the pattern of expression of pro-inflammatory (IL-1 beta, IL-6, TNF-alpha), Th1 (IFN-gamma IL-2), and Th2 (IL-4) cytokines. Immunohistochemistry was also used to localize morphologically IFN-gamma and IL-4. Our results show that pro-inflammatory cytokines and Th1 cytokines are mainly expressed in IIM. The accumulation of mononuclear inflammatory cells and the inflammatory syndrome in IIM are probably related in part to the production of pro-inflammatory cytokines. Moreover, the pattern of local cytokine expression is consistent with a Th1 immune response related to autoimmune diseases.

Cytokines↗
PubMed1998

A guinea pig model for Q fever endocarditis.

A new model of experimental endocarditis, using electrocoagulation of native aortic valves, was used for the study of Q fever endocarditis. In the 20 guinea pigs electrocoagulated and inoculated with Coxiella burnetii Nine Mile phase I strain, 10 presented with infective endocarditis. Of these, 7 died spontaneously. All guinea pigs with endocarditis presented with blood cultures positive for C. burnetii, and C. burnetii antigen was found in their cardiac valves. Positive blood cultures or valvular immunopositive cells were not identified in either nonelectrocoagulated or noninoculated controls. This experimental model demonstrates that Q fever in an animal with previously damaged valves results in endocarditis. It could provide a new tool for the investigation of pathophysiology and antibiotic therapy for Q fever endocarditis.

Animals↗
PubMed1997

Guinea pig model for Staphylococcus aureus native valve endocarditis.

We present a new experimental model of Staphylococcus aureus infective endocarditis in guinea pigs. Permanent aortic valve damage was produced by electrocoagulation after catheterization of the right carotid artery, which allowed avoidance of the intracardiac catheter to produce cardiac vegetations. Our model closely mimics pathological mechanisms of native valve endocarditis.

Animals↗
PubMed1997

Pathologic changes during acute Q fever: influence of the route of infection and inoculum size in infected guinea pigs.

As assessed by both standard histological staining and immunochemistry, intraperitoneal inoculation of C. burnetii in guinea pigs led to pathologic changes mainly in the liver, whereas intranasal inoculation led to pathologic changes mainly in the lungs. Myocarditis and positive blood cultures were observed only in those animals which received the highest inoculum. We therefore conclude that both the route of infection and the size of the inoculum influence clinical expression in acute Q fever.

Acute Disease↗
PubMed1996

Familial desmin myopathies and cytoplasmic body myopathies.

Clinicopathological, immunohistochemical and biochemical studies were performed on seven patients from five families showing an abnormal accumulation of desmin in the muscle fibers. Late onset myopathy was observed in all the cases studied. The clinical features were heterogeneous and usually nonspecific. However, some patients presented with dysphonia, dysphagia or cardiomyopathy. These features are highly suggestive of desmin myopathy. Using electron microscopy, desmin myopathy is characterized by an accumulation of granulofilamentous material. Depending on the distribution of the material, however, three different patterns of desmin accumulation can be observed: (1) large circumscribed inclusions, (2) intermyofibrillar areas of diffusely distributed material, and (3) deposits around large spheroid bodies. The second pattern is characterized by a rubbed-out appearance using oxidative enzyme reactions. For all the patients studied here, the immunohistochemical data showed that the desmin accumulation fitted these three patterns of distribution. For six patients, immunoblot analysis confirmed the desmin accumulation patterns and showed that an increase in the expression of the 53-kDa protein had occurred. The third pattern of desmin accumulation confirms the pathological heterogeneity of cytoplasmic and spheroid bodies. Desmin does not accumulate in all cytoplasmic and spheroid body myopathies, as observed in two other familial cases presented here.

Adult↗
PubMed1996

Acquired multifocal myofibrillar disruption selective of type II fibres.

We report three cases of patients who complained of myalgia showing histological features similar to tubular aggregates in their muscle biopsies. All had an elevated erythrocyte sedimentation rate without any evidence of infectious or autoimmune disease. On electron microscopy, small areas of myofibrillar degeneration, selectively in type II fibres, were found in all patients, but no tubular aggregates were seen. Although the pathogenesis of these lesions is unclear, it does seem that this condition is acquired and transient.

Adult↗
PubMed1996

Upregulation of tumor necrosis factor alpha and interleukin-1 beta in Q fever endocarditis.

The occurrence of Q fever endocarditis likely involves some alterations in the responses of monocytes, the in vivo targets of Coxiella burnetii. To test this hypothesis, the production of the inflammatory cytokines tumor necrosis factor alpha, interleukin-1 beta, and interleukin-6 was assessed in monocytes from patients with Q fever endocarditis. Spontaneous transcription and secretion of tumor necrosis factor and interleukin-1 were significantly higher in patient monocytes than in healthy controls. The interleukin-6 transcripts were also upregulated in patient cells. Moreover, in patients with recent endocarditis exhibiting high titers of immunoglobulin G directed to C. burnetii in phase I, monocytes released significantly higher levels of tumor necrosis factor and interleukin-1 than in patients with stabilized endocarditis. Immunoglobulin G titers and the overproduction of tumor necrosis factor and interleukin-1 were significantly correlated. Hence, the overproduction of inflammatory cytokines might be a marker of disease activity.

Adult↗
PubMed1996

[Urachal adenocarcinoma associated with urothelial tumor of the bladder. Report of a case].

The authors report a rare association of adenocarcinoma of the urachus and urothelial bladder carcinoma. Treatment consisted of cystoprostatectomy with removal of the urachus and cutaneous ureterostomy. A review of the literature indicates that adjuvant treatment has yet to be defined. This is a chance association whose prognosis depends on the invasive nature of the urothelial tumour.

Adenocarcinoma↗
PubMed1995

Differential expression of cell adhesion molecules (CAM), neural CAM and epithelial cadherin in ependymomas and choroid plexus tumors.

A series of frozen specimens of 18 ependymomas and 7 choroid plexus tumors were examined for their expression of cell adhesion molecules, such as neural cell adhesion molecule (NCAM), its polysialylated isoforms (PSA NCAM), and epithelial (E-) cadherin, and of intermediate filament proteins, such as glial fibrillary acidic protein (GFAP) and cytokeratin, using various monoclonal and polyclonal antibodies. Normal choroid plexus and ependyma were taken as controls. Anti-E-cadherin immunoreactivity was observed on the basolateral part of most adult choroid plexus and benign choroid plexus papilloma cells. However, a small number of atypical papillomas and carcinoma cells showed anti- E-cadherin immunoreactivity throughout their cell surface membrane. NCAM were not expressed by adult choroid plexus and benign papilloma cells. Only a few cells expressed NCAM and PSA NCAM in developing choroid plexus, atypical papillomas and carcinomas. Cytokeratin expression was always observed in choroid plexus and their tumors; GFAP expression was variable from case to case. In contrast, ependymal cells and their tumors never expressed E-cadherin but strongly expressed NCAM. PSA NCAM was found in ependymomas exhibiting anaplastic features. All ependymomas strongly expressed GFAP and a few demonstrated slight expression of cytokeratin. These data suggest that, besides GFAP and cytokeratin, NCAM and E-cadherin are of potential diagnostic value in distinguishing choroid plexus tumors from ependymomas. E-cadherin and NCAM may play a role in the functional organization of normal choroid plexus and ependyma, respectively. In particular, incomplete or irregular anti-E-cadherin expression in choroid plexus tumors and PSA NCAM immunoreativity in ependymomas and choroid plexus tumors correlates with the emergence of anaplastic histological features.

Adolescent↗