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T Molina

Publications and source records attributed to T Molina.

At least 73 records · Page 4Linked to original sources
PubMed1995

Lymph node involvement revealing a lymphomatous polyposis of the gastrointestinal tract.

The digestive tract is the most frequent site of extranodal malignant lymphomas. Lymphomatous polyposis is one of them, and its prognosis is poor. It corresponds to a digestive localization of mantle cell lymphoma. In most cases it is discovered following digestive symptoms. However, in some cases this digestive malignant lymphoma may be asymptomatic. Thus complete endoscopic exploration of the digestive tract including biopsies is necessary for every patient presented with lymph node mantle cell lymphoma.

Adult↗
PubMed1995

Tat-induced lesions in transgenic mice do not correlate with the HIV-1 LTR transactivation.

The product of the tat gene is the most potent transcriptional trans-activator of the HIV-1 LTR (Human Immunodeficiency Virus type 1 Long Terminal Repeat) and might be predicted to be one of the HIV-1 proteins involved in the pathogenesis of AIDS-associated tumors. Deciphering its role in vivo may imply generation of transgenic mouse models displaying different spectra of tat expression. However, it remains difficult to correlate the mRNA expression, the protein production and the eventual pathological consequences in the animal. Our goal in this work was to elaborate a binary transgenic system allowing such an approach, the correlation of the transgene expression in different tissues and the production of the Tat protein, tested as a trans-activator in vivo, with its pathogenic effects. No direct linkage was evident between the degree of transactivation and pathogenesis. Indeed, only benign lesions were observed in malpighian epithelia, where the production of the Tat protein was clearly evidenced by its transactivating property.

Animals↗
PubMed1994

[Splenoma with accumulation of megakaryocytes during the course of an idiopathic myelofibrosis].

We report a splenoma associated with an important megakaryocyte sequestration in peliotic sinuses. The diagnosis was done on surgical specimen of splenectomy performed for a painful splenomegaly occurring in a 71-year-old man presenting a primary idiopathic myelofibrosis. Histopathological features of these splenic microvascularization disorders, mainly occurring during hemopathy involving the spleen, are discussed. This case seems to confirm the hypothesis that splenoma could be an acquired splenic disease.

Aged↗
PubMed1993

Requirement for tyrosine kinase p56lck for thymic development of transgenic gamma delta T cells.

The Src-related protein tyrosine kinase p56lck is essential for antigen-specific signal transduction and thymic maturation of T cells that have an alpha beta T cell receptor (TCR), presumably by physical association with CD4 or CD8 molecules. To evaluate the requirement for p56lck in the development of T cells that have gamma delta TCRs, which generally do not express CD4 or CD8, p56lck mutant mice were bred with TCR gamma delta transgenic mice. Few peripheral cells that carried the transgenes could be detected in p56lck-/- mice, although 70 percent of thymocytes were transgenic. Development of transgenic gamma delta+ thymocytes was blocked at an early stage, defined by interleukin-2 receptor alpha expression. However, extrathymic development of CD8 alpha alpha+ TCR gamma delta+ intestinal intraepithelial lymphocytes appeared to be normal. Thus, p56lck is crucial for the thymic, but not intestinal, maturation of gamma delta T cells and may function in thymic development independently of CD4 or CD8.

Animals↗
PubMed1992

[Contribution of immunohistochemistry and in situ hybridization techniques in diseases caused by or associated with Epstein-Barr virus].

Epstein-Barr virus is associated with many diseases. Today, the pathologist may study either by immunohistochemistry or in situ hybridization on tissue sections: EBV genome, EBV messenger RNA, EBV latent and replicative proteins. Several technics can be performed on fixed paraffin-embedded tissue to demonstrate the presence of EBV DNA, EBER-1 RNA, LMP-1 protein. Frozen tissues are required for the study of EBNA-2, ZEBRA and replicating proteins expression. The results, obtained during the study of benign and malignant proliferations always or often associated with EBV, such as infectious mononucleosis, Burkitt's lymphomas, AIDS associated lymphomas, lymphoproliferations in immunocompromised patients, Hodgkin's disease, and some epithelial proliferations, are summarized.

Acquired Immunodeficiency Syndrome↗
PubMed1991

Time-course development of differentiated hepatocarcinoma and lung metastasis in transgenic mice.

A precise targeting of the SV40 T early region expression in the liver of transgenic mice was obtained using 700 bp of the antithrombin III regulatory sequences to control oncogene expression. In the strain expressing the highest level of large T antigen (Tag), the incidence of hepatocarcinoma was 100%. The evolution was reproducible and characterized by a marked cytolysis occurring as early as 4 weeks, when no morphological and histological modifications were visible, a preneoplastic state marked by a progression from hyperplasia to proliferative nodules composed of highly differentiated cells exhibiting a high Tag expression, which elicited tumor formation in nude mice and could proliferate in vitro, and hepatocellular carcinoma associated, in 10% of the cases, with lung metastasis. These transgenic mice constituted a useful model for therapeutic assays and fundamental studies on carcinogenesis.

Animals↗
PubMed1990

[Non-Hodgkin's lymphoma in HIV infection. A multicenter retrospective study of 21 cases].

The incidence of non-Hodgkin's malignant lymphoma is known to be increased in patients who are seropositive for the human immunodeficiency virus (HIV). We report here a multicentre retrospective study of 21 HIV-positive patients with non-Hodgkin's lymphoma seen between 1985 and 1987. All phenotype B lymphomas of intermediate or high malignancy grade according to the Working Formulation are difficult to classify histologically. Because of this problem, reexamination of the specimens by several pathologists and perhaps also the use of other morphological prognostic criteria, such as mitotic index, seem to be desirable. In more than one-third of our patients the presence of a lymphoma led to the finding of HIV seropositivity in subjects who were all issued from populations at risk. Median age was 39 years. Spread evaluation showed stage III or IV in most cases with, in 4 out of 5 patients, extranodal sites, notably the neuromeningeal system, liver, gastrointestinal tract and bone marrow. The median overall survival was 5 months, but in April 1989 2 patients had survived for more than 30 months. Obtaining complete remission (11/21 cases) was imperative for a 10 months' survival. Eight of the 11 patients in whom complete remission was obtained had received the heavy induction chemotherapy required by the degree of malignancy, but no death due to drug toxicity was recorded. 17 patients died, with active lymphoma (12 cases) and/or infection (8 cases) being documented at the time of death. The finding of more than 500/sq. mm CD4 lymphocytes in peripheral blood in 10 cases while the lymphoma was developing, and the heterogeneity of the Epstein-Barr virus (EBV) profile in serum raise the question of the role played by T-cell immunodeficiency and by EBV infection in the physiopathogenesis of these lymphomas.

Adult↗
PubMed1989

Functions of polymorphonuclear leukocytes and individuality of Jorge Lobo's disease: absence of the specific leukocyte digestive defect against Paracoccidioides brasiliensis.

Peripheral blood neutrophils (PMNs) from a patient with Jorge Lobo's disease (JLD) digested well phagocytosed Paracoccidioides brasiliensis. We found no circulating antibodies against P. brasiliensis in the patient's serum. Such neutrophils showed myeloperoxidase activity and also digested normally phagocytosed Candida albicans. We had previously reported the presence of a specific digestive deficiency of PMNs from patients with paracoccidioidomycosis (PARA) vis à vis P. brasiliensis. Current findings provide new information about leukocyte functions in JLD and bolster the view that JLD, PARA and their respective causative microorganisms are distinct.

Antibodies, Fungal↗
PubMed1988

Polymorphonuclear leukocyte functions in psoriasis.

Circulating polymorphonuclear leukocyte (CPMN) functions were studied in patients with widespread psoriasis as well as in persons with chronic alcoholic liver disease (CALD), paracoccidioidomycosis, diverse granulomatous diseases, and normal individuals. We were unable to find stimulation or increase in CPMN functions in patients with psoriasis compared to normal individuals. Leukocytes from individuals with CALD had a lowering of their metabolic activation, chemotaxis, random movement, and adherence. CPMNs from patients with paracoccidioidomycosis showed a significant deficiency in their ability to digest Paracoccidioides brasiliensis. Our results are against the concept that functions of circulating PMNs are stimulated in psoriatics.

Adolescent↗
PubMed1987

[Hodgkin's nodular paragranuloma (nodular Hodgkin's disease, with lymphocytic predominance): apropos of 29 cases].

The clinical and morphological features of 29 cases of nodular Hodgkin's disease, lymphocyte predominance type (NLPHD) are reported. This disease must be distinguished from other forms of Hodgkin's disease due to its nodular pattern with predominance of small lymphocytes, without sclerosis. Its main feature is the presence of rare lymphocytic histiocytic type Reed-Sternberg cells (LHRS). From a clinical point of view, we observed that the primary lymph nodes involvement are mostly seen in cervical and axillary sites, with a clinical stage I or II at diagnosis, without biological signs of activity and with a good prognosis and long duration of the disease. Two main aspects may be underlined: the frequent relapses after biopsy in lack of treatment, and a possible transformation into a large B cell lymphoma. Immunohistological stainings suggest that LH-RS cells are transformed B cells. NLPHD is a clinicopathological entity which must be currently considered and treated as Hodgkin' disease.

Adolescent↗
PubMed1985

A novel method for estimating killing ability and digestion of Paracoccidioides brasiliensis by phagocytic cells in vitro.

We describe a novel method by which phagocytosis, digestion and killing of Paracoccidioides brasiliensis yeast cells by polymorphonuclear leukocytes or other phagocytic cells may be estimated simultaneously. Suspensions of P. brasiliensis (yeast-like phase) were sonicated, counted and incubated at 37 degrees C with known numbers of phagocytes. Control preparations contained no phagocytic cells. At given intervals samples were incorporated into gelatin nutrient medium and droplets of the mixtures were incubated at room temperature. Live yeast-like P. brasiliensis germinate in vitro and produce filaments. After incubation, droplets may be melted and examined under phase contrast optics, or the cells may be washed and stained by a variation of Papanicolaou's method. Digested P. brasiliensis, intact but non-germinating yeasts and filamented (viable) yeasts may be identified and counted. Killing and digestive abilities of phagocytes may be estimated by the difference between values obtained from phagocyte-containing and control preparations.

Cells, Cultured↗
PubMed1980

Studies on plating efficiency and estimation of viability of suspensions of Paracoccidioides brasiliensis yeast cells.

Mild sonication was used to obtain single cell suspensions of Paracoccidioides brasiliensis. These cells were intact by microscopic criteria. Direct cell counts in a given inoculum and colony formation on various media were used to determine plating efficiency. Sonicated and nonsonicated cell suspensions were used to study plating efficiency and to estimated viability by means of vital dyes. Methylene blue Erythrosin B, and Janus green were unreliable when used with P. brasiliensis, but vital dyes were accurate when tested with Candida albicans. Acridine orange gave more meaningful results of viability. Estimates of viability, however, changed significantly as a result of relatively minor alterations in the composition of the suspending medium. In initial experiments, the plating efficiency of P. brasiliensis was dismally low. It descended abruptly with increasing dilution of inoculum. Efficiency was much improved if horse serum was added to brain heart infusion plates or if glucose glycine yeast extract (GGY) plates were incubated at room temperature and mycelial colonies were counted. With the technique we report, current plating efficiency of sonicated suspensions is of the order of 25%. Our results and procedures have an important bearing upon those studies concerned with in vitro killing of P. brasiliensis in suspensions or with isolating this fungus from clinical or environmental specimens.

Acridine Orange↗
PubMedDate not supplied

[Plasma cell leukaemia].

We report a case of primary plasma cell leukaemia, with an absolute count of plasma cells of 53 Giga/L, diagnosed in a 83-year-old woman. The patient's condition improved, with no circulating plasma cells after 3 weeks of treatment, in response to the combination of thalidomide and dexamethasone administered for 5 days followed by thalidomide alone. The clinical presentation, the morphological, flow cytometric and pathophysiological characteristics of the plasma cell leukaemia and the treatment are summarised in this paper.

Aged, 80 and over↗
PubMedDate not supplied

Initial lesions of classical Hodgkin's lymphoma of the nodular sclerosis type.

The necessity of correct diagnostics of initial lesions of Hodgkin's lymphoma is underlined. The correct assessment may relate of more than 90% of such observation to 90% of noduler sclerosis. The criteria similar to those of WHO are suggested for the differentiation with mixed-cell or lymphoid preponderance.

Hodgkin Disease↗
PubMedDate not supplied

[Use of ticlopidine in primary care].

OBJECTIVES: To find the reasons for prescription of Ticlopidine, which acts against the aggregation of platelets and is catalogued as "with hospital diagnosis", and to evaluate the criteria for its correct use and whether it is actually used in Spain to treat authorised symptoms. DESIGN: A descriptive, crossover and retrospective study. SETTING: Primary Care districts in the catchment area of the Virgen del Rocío hospital in Sevilla. PATIENTS: Those who requested permits for Ticlopidine prescriptions, documented by the clinical report. MEASUREMENTS AND MAIN RESULTS: The following data were recorded from the clinical reports presented when the Ticlopidine prescription permits were requested: patient's identification, diagnosis, pharmaceutical speciality, dosage, length of treatment and recommendation of haematological check-ups. Out of 407 reports available, the diagnosis corresponded to one of the authorised symptoms in 50.6% of cases. In a third of the patients the recommended dose was half that endorsed by the published clinical trials. Only in 2.7% of cases was mention made of the desirability of having haematological check-ups to forestall possible adverse reactions. The possibility of a counter-indication to Acetylsalicylic acid was only rarely mentioned. CONCLUSIONS: Ticlopidine is recommended in 50% of cases for symptoms for which it is not authorised in our country: moreover, in 35% of cases, at doses lower than those established as effective. The information given by the doctor who initiates the treatment is usually insufficient. There is a need to reassess whether cataloguing a medicine as "with hospital diagnosis" aids its rational use.

Aged↗