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N Horschowski

Publications and source records attributed to N Horschowski.

At least 37 records · Page 2Linked to original sources
PubMed1994

The maedi-visna virus Tat protein induces multiorgan lymphoid hyperplasia in transgenic mice.

Sheep infected with maedi-visna virus experience immunological disorders leading to progressive chronic diseases involving the brain, lung, spleen, and lymph nodes. To study the biological activity of the viral transactivating Tat protein, we generated transgenic mice carrying the tat gene. Analysis of the transgenic mouse tissues for tat mRNA revealed that while low at the messenger level, the expression of the transgene correlated with dramatic follicular lymphoproliferative disorders involving the lung, spleen, lymph nodes, and skin. This finding suggests that the viral protein possesses a high pathological potency. Our findings show that the maedi-visna virus tat gene product contributes to the pathogenesis of multiorgan proliferative disorders associated with maedi-visna virus infection.

Animals↗
PubMed1994

Lymphomatoid papulosis and Hodgkin's disease: report of a case.

The authors report the case of a 67-year-old-man who presented with stage IIIAa Hodgkin's disease (HD) almost 17 years after developing CD30+ type A lymphomatoid papulosis (LP). Combination chemotherapy resulted in a complete remission of the HD for 2 years, although the LP continued relentlessly as before. A possible link between HD and LP is discussed in the light of similar cases reported in the literature.

Aged↗
PubMed1992

Acute monocytic leukemia: prevalent cutaneous lesions. Two cases.

The authors report two cases of acute myeloid leukemia with prevalent cutaneous lesions. The positivity of granulo-monocytic antibodies and the exclusive cutaneous site of the lesions drove them previously to the diagnosis of histiocytic sarcoma. These cases stress the problem of the immunological identification of cutaneous lymphomas of "histiocytic" type.

Aged↗
PubMed1991

Cutaneous lymphomas of phenotypically undetermined lineage: contribution of genotypic analysis.

Genotypic analyses were performed in six primary cutaneous lymphomas whose lineage could not be assessed on the basis of histologic and phenotypic data. By immunophenotyping, these neoplasms expressed leukocyte common antigen and HLA-DR but did not show consistent immunostaining for B-cell or T-cell differentiation antigens. Expression of nonspecific histiocytic markers such as lysozyme and alpha 1-antitrypsin was found in three cases. By genotyping, three cases retained a germline configuration and immunoglobulin gene rearrangement was observed in one case, T-cell receptor gene rearrangement was found in one case, and both types of rearrangements in one case. Of the three patients in whom gene rearrangements were noted, two rapidly died and the other patient, with a dual genotype, is still alive 15 years after diagnosis. The three patients without gene rearrangements are alive and well after a mean follow-up of 2.5 years. It appears that cutaneous lymphomas with an uncertain phenotype include at least some cases of authentic B-cell or T-cell lymphomas. The germline configuration that we observed in cases with a chronic course remains difficult to explain. It may be related to a low malignancy form of histiocytic lymphoma, an atypical polyclonal hyperplasia, or even a low-grade lymphoma arising from a primitive cell without established commitment to either B- or T-cell lineage.

Adult↗
PubMed1991

Lymphadenopathic tumor exhibiting intermingled features of Kaposi's sarcoma, malignant lymphoma, and angiofollicular hyperplasia.

A 56-year-old man presented with an inguinal lymph node enlargement. Histologic study of the tumor revealed three intermingled pathologic lesions: a nodular small cell lymphoma, an angiofollicular hyperplasia of vasculohyaline type, and a vascular neoplasia closely resembling Kaposi's sarcoma. The patient was immunocompetent and denied any homosexual relationships, transfusions, or drug use. The serum was negative for the presence of human immunodeficiency virus antibody. Computed tomographic scan and ultrasound examination revealed no other lymphadenopathies. This case shows that both hyperplastic and neoplastic lymphoid proliferations can occur simultaneously with vascular neoplasia. It thereby suggests that the neoplastic populations might interact to favor the tumor growth, the sequence and the nature of the stimulating events remaining unclear.

Castleman Disease↗
PubMed1991

Histological evolution of peripheral T-cell lymphomas. Study of six cases.

The authors report 6 cases of histological transformation in peripheral T-cell lymphomas of low grade of malignancy. The transformation occurs in 75% of the cases, in extra-nodal sites and corresponds to a monomorphic of pleiomorphic large cell type. There is no discordance in the immunologic results between the two phases. The transformation seems to occur earlier than in B lymphomas, with a relative frequency of hematological manifestations and no therapeutic response.

Aged↗
PubMed1991

[Duodenal sarcoidosis with selective IGA deficiency and lymphoid nodular hyperplasia].

Coexistence of IgA deficiency with sarcoidosis has been reported occasionally. Enteropathy occurs exceptionally in this association. We report the case of a 45 year-old woman experiencing disseminated sarcoidosis which involved mediastinum, chest, lymph nodes, liver, bone marrow, and skin. Immunoglobulin deficiency involving essentially IgA was found 15 years later. Digestive investigations showed gastroduodenal specific localizations associated with lymphoid nodular hyperplasia without villi atrophy.

Adrenal Cortex Hormones↗
PubMed1990

What's new in primary central nervous system lymphomas?

Primary central nervous system lymphomas (CNSL) are uncommon neoplasms accounting for about 1% of primary brain tumors. Patients with congenital or acquired immunodeficiencies including AIDS patients and transplant recipients represent the main high-risk population for CNSL occurrence. An important point emerging from the literature is that CNSL incidence has dramatically increased during the last years not only in HIV infected patients by virtue of the AIDS epidemic spread, but also for unclear reasons in immunologically normal persons. Although c-myc oncogene activation and Epstein-Barr virus infection are considered to play a role in CNSL development, the peculiar tendency of these lymphomas to occur and remain inside the CNS is not well understood and may involve putative CNS binding molecules carried by lymphocytes. The clinical presentation is characterized by a great variety of neurological disorders. Radiological features consist of hyperdense homogeneous deposits within the subcortical white matter with a pattern of marked enhancement after injection of contrast material. The tumor masses are usually ill-defined and multicentric. Although all cytological types can be observed, the most common types belong to the high-grade category of non-Hodgkin's lymphoma. Monoclonal antibodies reactive with formalin-fixed, paraffin-embedded sections can be used in conjunction with stereotactic needle biopsy to provide accurate immunological characterization of CNSL. The large majority of CNSL is of B-cell origin but T-cell lymphomas seem at the present time less exceptional than previously thought. Although radiotherapy and chemotherapy can increase length of survival, the prognosis of CNS remains dramatically poor, the shortest survival being observed in AIDS patients.

Humans↗
PubMed1990

Genotypic analysis in large cell lymphomas expressing a restricted set of differentiation antigens.

Immunophenotyping and immunogenotyping were performed in a series of 8 large cell lymphomas exhibiting anaplastic or "histiocytic" morphology and displaying an uncertain phenotype due to a restricted number of differentiation antigens. 6 cases expressed the Ki-1 antigen. 4 cases expressed one or two B-cell markers and contained rearrangements of the immunoglobulin genes. One of them also exhibited a T-cell receptor (TCR) beta gene rearrangement. 3 cases expressed a single T-cell differentiation antigen. Among them, only 1 displayed both gamma and beta TCR gene rearrangement; 1 only contained a gamma TCR gene rearrangement and 1 completely lacked clonal rearrangements. The eight cases expressed an inconclusive immunophenotype due to an abundant population of reactive cells but showed an immunoglobulin gene rearrangement. In conclusion, 5 out of the 8 unusual lymphomas studied here could be characterized by immunogenotyping. This approach was, however, inconclusive in the 3 remaining cases, whose lineage and differentiation stage remain poorly defined.

Adult↗
PubMed1990

Rearrangement of the beta T-cell receptor gene in a monocytoid B-cell lymphoma.

We describe an unusual case of monocytoid lymphoma displaying a rearrangement of the T-cell receptor beta-chain gene associated with a rearrangement of the immunoglobulin heavy-chain gene, and of the lambda light-chain gene. This lymphoma was morphologically similar to previous cases in the literature, and was clinically of low grade. The lymphoma expressed the lambda light chain, HLA-DR, CD21, and CD22. Though the B-cell lineage of this lymphoma seems very likely, the genotypic profile raises a cautionary note regarding the supposed high stage of differentiation of monocytoid lymphomas.

B-Lymphocytes↗
PubMed1990

[Multicentric bone chloroma disclosed by pleural cytology].

We report a case of granulocytic sarcoma of the bone with pleural involvement diagnosed upon cytologic analysis of the pleural fluid (centrifugation spots stained by May-Grunwald-Giemsa) and confirmed by more complex investigations, i.e., demonstration of granulomonocytic membrane antigens by immunohistochemical monoclonal antibody techniques on frozen sections of the tumor. This case draws attention to the value of cytologic studies in granulocytic sarcomas whose histologic features are suggestive of lymphoma.

Adult↗
PubMed1990

[Contribution of the analysis of genotype to the diagnosis of malignant lymphoma with abundant epithelioid reaction. Apropos of a case].

The authors describe the case of a 67 year-old woman bearing a malignant lymphoma displaying two different histological patterns: a Lennert's lymphoma pattern in a cervical lymph node and a diffuse centroblastic lymphoma pattern in an axillary node. Immunophenotyping on frozen and paraffin sections showed a predominant positivity of T-cell markers in the cervical node, while the axillary lymphadenopathy exhibited a major positivity of B-cell markers and a restricted expression of the lambda light chain. However, genotyping provided the evidence of a single neoplastic B-cell clone proliferating in both cervical and axillary nodes. These findings suggest that histological pattern of Lennert's lymphoma is devoid of absolute specificity. Thus, genotypic analysis is a useful tool for the diagnosis of so-called "lymphoepithelioid lymphomas".

Aged↗