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Biomedical subjects

C Rivas

Publications and source records attributed to C Rivas.

At least 73 records · Page 4Linked to original sources
PubMed1996

Evaluation of the international index in the prognosis of high grade gastric malt lymphoma.

The International Prognostic Index identifies four risk groups with different survival rates in aggressive non-Hodgkin's lymphoma. We have studied whether a slight modification of this index has prognostic significance in high grade gastric B-cell MALT lymphoma. In 53 patients with high grade gastric B-cell MALT lymphoma the following survival factors were investigated: age over or under 60 years, sex, B symptoms, more than one extranodal site of involvement other than the stomach, serum LDH levels, performance status, stage I/IIE1/IIE2 v.s. stage III/IV, treatment with surgery, chemotherapy or both modalities together and the four risk groups as defined by the Modified International Prognostic Index (MIPI). A multivariate Cox's test was used to evaluate the independent prognostic significance on survival of all the above variables. Advanced stage (III/IV) and involvement of more than one extranodal site not including stomach were the only variables influencing survival. The MIPI was not sufficient to separate groups with significant differences in survival or to stratify prognostic groups. In this series, the MIPI did not show prognostic significance in high grade gastric B-cell MALT lymphoma.

Adolescent↗
PubMed1996

Metabolic effects of the combination of furosemide and captopril in rat.

Diuretics typically provoke increased serum lipid levels and may provoke increased serum uric acid levels and/or glucose intolerance. Furosemide is widely used as an antihypertensive, but in patients for whom furosemide treatment alone proves insufficient to reduce hypertension, a common procedure is to co-administer the angiotensin-converting-enzyme (ACE) inhibitor captopril. The metabolic effects in rats of joint administration of furosemide (15 mg/kg/day) and captopril (2 mg/kg/day) are evaluated over a two-week period. At the end of this period, the serum levels of lipids, uric acid, bilirubin, proteins and various enzymes were determined as well as the effect of the treatment on intestinal absorption of glucose and calcium. Furosemide/captopril led to an increase in serum albumin and alkaline phosphatase levels, and a decrease in triglyceride levels. The results of this work support the view that this drug combination is suitable for hypertension treatment.

Alanine Transaminase↗
PubMed1996

[Histopathology of bone marrow biopsy in patients with human immunodeficiency virus infection].

PURPOSE: To describe morphology of bone marrow (BM) biopsy in HIV infected patients. To correlate histopathologic findings and clinico-haematological data. To consider the advantages of this method (BM biopsy) in the diagnosis of secondary infectious or tumoural accompanying processes. MATERIAL AND METHODS: One hundred and fourteen BM biopsies of 103 HIV infected patients were retrospectively reviewed. The cases were selected from the records of Pathology Department of Jiménez Díaz-Foundation (from 1984 to 1993). All cases were studied with routine and immunohistochemical (IHQ) techniques against haematopoietic and proliferative markers. Clinico-haematological data were also reviewed. RESULTS: Ninety per cent of biopsies showed morphological abnormalities: hypercellularity, myeloid hyperplasia and dysplasia of erythroid and megacariocytic series. Reticuline myelofibrosis and reactive lymphoplasmacytosis were also present. IHQ confirms the described histopathologic pattern. Twenty-two per cent of cases showed signs of infectious or tumoural diseases: mycobacteriosis (15%) and lymphomas (7%). Clinical manifestations were correlated with significant alterations in the BM: fever with hypercelullarity, constitutional syndrome and myelofibrosis with zidovudine therapy and infections with myelodysplasia. CONCLUSIONS: Cytology, myelofibrosis and abnormal pattern of BM biopsies in HIV infected patients are characteristic: "the so-called AIDS BM pattern" as BM is a target organ in the HIV-related infections. BM biopsies are a good method to demonstrate stage of HIV disease and accompanying infectious or tumoural processes.

Adult↗
PubMed1996

[Clinico-morphologic reconsideration of anaplastic lymphoma. Retrospective study of 60 patients with aggressive clinical course and multiple recurrences].

PURPOSE: To identify anaplastic large cell lymphoma Ki-1+ (ALCL-Ki-1+) among a group of patients with aggressive Hodgkin's disease (HD) and to know the biological behaviour of the neoplasia (ALCL-Ki-1+). PATIENTS AND METHODS: Biopsies and clinical data of sixty patients with previous morphological diagnosis of HD lymphocytic depletion (LD), syncytial variant of nodular esclerosis (NE-II) and other subtypes of HD with aggressive clinical features were reviewed. A morphological, immunohistochemical (IHQ), proliferative and flow cytometric (FCM) studies were performed in lymph node biopsies. RESULTS: Morphological study and IHQ identify three groups: 15 patients (25%) lymphocytic predominance (LP) HD, 36 (60%) ALCL-Ki-1+ and 9 (15%) of non-Hodgkin's lymphoma (NHL) and unclassifiable cases. Nine cases of LP show anaplastic and variable immunophenotype being the rest of B-cell nature. 75% of LP patients showed long survival and frequent second neoplasias (47%). ALCL-Ki-1+ group had good initial response to therapy (84%) and multiple relapses, 67% showed CD15 positive marker (the so-called ALCL-HD related). CONCLUSIONS: A retrospective study of a selected group of patients previously diagnosed of aggressive HD showed different pathological subtypes: LP, LP with anaplastic areas, ALCL-Ki-1+ Hr (Hodgkin's related) and ALCL-Ki-1+ (classical type), all of them were CD30+, which could represent different stages of the same neoplasia.

Adolescent↗
PubMed1996

[Mechanism of phototoxicity induced by drugs].

First of all some general concepts are given on phototoxic activity of pharmaceutical products which full fill the structural characteristics required to decompose by light and to cause biological damage, either themselves, their photoproducts or the products of their metabolism. These considerations are important due to the fact that this field of research is fairly new. Next, a review is given on recent research carried out in this laboratory on the photochemistry and phototoxicity of fibric acid and their derivatives and finally a review is made as well on the photochemistry and phototoxicity of antibacterial quinolones. Mechanisms are postulated for the photochemical decomposition of the substances investigated and possible mechanism for the in vitro activity at cellular level are also presented.

4-Quinolones↗
PubMed1995

[Expression of latent membrane protein (LMP) in large-cell anaplastic lymphomas].

PURPOSE: The presence of Epstein-Barr virus (EBV)-encoded latent membrane protein (LMP) was investigated in 40 cases of lymphoproliferative diseases which include Hodgkin's disease (HD), anaplastic large cell lymphoma (ALCL) and non-Hodgkin's lymphoma (NHL) of B and T-cell nature. MATERIAL AND METHODS: All cases were immunophenotyped in paraffin-embedded lymph node tissues, with a complete panel of monoclonal antibodies against B-cells, T-cells, histiocytes, activation and proliferation markers and classified as: 24 anaplastic large cell lymphoma (ALCL, 8 classical type and 16 ALCL-HD related), 10 lymphocyte predominant HD (LP, 5 classical type and 5 with ALCL areas), 4 NHL (two T-Cell type and 2 T-cell rich B-cell NHL). Immunohistochemistry techniques were performed ABC-complex and phosphatase alkaline anti-phosphatase alkaline (APAAP). RESULTS: LMP was detected in 35% (14/40) of total cases. In LP group one third of cases were LMP+. In ALCL-HD related cases 44% were LMP+ versus 13% in ALCL group. All LMP cases were CD30+ except one NHL-T and a T-cell rich B-cell NHL. The predominant immunophenotype was LMP+/CD20+ (57%) versus LMP+/CD20-. Most cases were of B-cell (36%) lineage. Null ALCL cases were LMP-. CONCLUSIONS: LMP, the most oncogenic EBV protein could play a pathogenic role in lymphoproliferative processes. It is not exclusive of HD and appears in other NHL preferentially of B-cell nature, above all in ALCL cases relating the two neoplasias HD and ALCL, both CD30 positive.

Herpesvirus 4, Human↗
PubMed1995

[Large-cell anaplastic lymphomas: a genetic and immunophenotypic study].

PURPOSE: To characterize from a genetic point of view a group of non-Hodgkin's anaplastic large-cell lymphomas (ALCL) by Southern blot and PCR methods with different probes (molecular study) and with direct or post 24-78 hours cultures with GTC banding techniques (cytogenetic). To correlate the results to the immunophenotype performed with a complete panel of monoclonal antibodies (MoAb) according to avidin-biotine and alkaline phosphatase (APAAP) methods. MATERIAL AND METHODS: Sixty cases of ALCL were reviewed and only 19 selected (with frozen or fresh material) because a complete immunohistologic and genotypic correlation had been done. According to CD15 expression two groups were considered, CD15+ (the so-called Hodgkin's related or Hodgkin's like) and CD15- or classical type. RESULTS: Only 26.5% of cases showed immuno -genotypic correlation. Immunohistochemistry is an accurate method for activation, proliferation and B-cell nature, but T-cell cases were not stained because T-cell paraffin markers are not completely specific. CD15 group had only 30% rearranged cases with scarce cytogenetic abnormalities, as it occurs in Hodgkin's disease (HD). ALCL classical type showed 66% rearranged cases, and one of the T-cell cases showed an incomplete t (2:5) translocation or polyploid cell lines. CONCLUSIONS: Both groups have different genetic and immunophenotypic behaviour which resembles HD or NHL. CD15 positive cases or ALCL HD-related constitute a borderline entity which has to be recognized because of the different therapy and clinical behaviour.

Hodgkin Disease↗
PubMed1995

[Characterization of mutation of the P53 gene in lymphomas].

PURPOSE: To analyze P53 mutations in a series of NHL and to determine its implication in the inactivation of the tumor suppressor function. MATERIAL AND METHODS: We analyzed 18 lymphomas by SSCP (exons 5 to 9) and subsequent sequencing technics to detect and characterize mutations on this gene. Loss of heterozigosity (LOH) was also studied with a VNTR near the p53 gene and with a intragenic microsatellite, comparing tumor and normal tissue. RESULTS: We found altered bands by SSCP in 5 cases, 4 of them have been described by sequencing analysis. One case was a polymorphism and the others were missense mutations. All mutations appeared in high grade lymphomas. Only one case showed LOH in both VNTR and microsatellite. CONCLUSIONS: This results suggest that p53 mutations may be associated with more malignant lymphomas.

Base Sequence↗
PubMed1995

Genetic instability of microsatellites in hematological neoplasms.

Genetic instability has been recently related to point mutations on genes involved in DNA repair pathway of errors produced during replication. These molecular alterations have been described in hereditary and sporadic colon carcinomas and related tumors. To examine genetic instability on lympho- and myeloproliferative processes, we analyzed the behaviour of 10 microsatellite markers and one VNTR on different chromosomes in 10 patients with non-Hodgkin lymphomas (NHL), one patient with acute lymphoblastic leukemia (ALL) and 10 patients with acute myeloid leukemia (AML). Mobility shifts were found in three of those cases. One of them showed genetic instability for several markers--microsatellites and VNTR- and the other two showed differences for only one marker. As a correlation between point mutations in MSH2 gene and the presence of genetic instability in hereditary non-polyposis colon cancer (HNPCC) and related tumors has been found, we analyzed the sequence of a conversed region of this gene in the cases showing this phenomenon. We only found a polymorphism, previously described, in 669 codon from cDNA.

Burkitt Lymphoma↗
PubMed1995

[Evaluation of specificity of pneumococcal antigen detection in clinical samples by using the polymerase chain reaction as reference method].

BACKGROUND: Sensitivity and specificity of latex agglutination test on samples obtained by transthoracic needle aspiration was evaluated for diagnosis of pneumococcal pneumonia by using the polymerase chain reaction as reference method. METHODS: Samples from 29 patients with community acquired pneumonia were processed for culture, antigen detection and polymerase chain reaction. The latex agglutination test was performed with a reagents kit (Slidex méningite kit, BioMérieux, France) using the procedure recommended by the manufacturer. The polymerase chain reaction was carried out by using two primers: Pn2x up and Pn2x down that amplify the PBP2x gene of Streptococcus pneumoniae. RESULTS: Culture was positive in 5 patients, antigen detection in 15 and polymerase chain reaction in 14 patients. The specificity of latex agglutination test was 93% compared with polymerase chain reaction as reference method. CONCLUSION: The pneumococcal antigen detection by latex agglutination test is as sensitive as the polymerase chain reaction, it seems to be highly specific, and it is rapid and easy to perform.

Antigens, Bacterial↗
PubMed1995

[T-cell-rich B-cell lymphoma: multifactorial study of 4 cases].

PURPOSE: With the correlational study of four cases in several areas (clinic, morphoimmunologycal, ultrastructural and genetic) we try to valorate the still controversial entity known as T-cell rich B-cell lymphoma (TRBL), and stablish some useful clues in order to settle down the differential diagnosis between TRBL, Hodgkin's disease (HD), and T-cell non-Hodgkin's lymphomas (TNHL). PATIENTS AND METHODS: Cases proceeded from Oncology Department, and had been firstly misdiagnosed either as HD (3 cases) or as TNHL (1 case). Biopsies were processed and stained in routine way, H&E, Giemsa and Wilder. Immunohystological study, using monoclonal antibodies against B-cells, T-cells, histiocytes, activation and proliferation markers, was also performed with avidin biotine peroxidase (ABC) method. Ultrastructural study was performed in three of the cases; two patients were studied by PCR and Southern blot. RESULTS: All of the cases showed a diffuse hystological pattern, with variable fibrosis, and proliferation of venules and capillaries. Small lymphoid cells, being positive for CD3, were dominant. Large blastic cells, positive for CD20, some of them with a Sternberg-like appearance, could be found, in a spitty pattern. Histiocytes were abundant and positive to CD68. Proliferation index (Ki-67) ranged between 13 and 24.5% being the stain mainly positive for B-cells and in a certain extent, also for T-cells. Ultrastructural features were closer to those of the NHL than to the ones found in HD. Molecular study failed to prove any rearrangement. CONCLUSIONS: TRBL is a rare entity between B-cell NHL group. Diagnosis and differential diagnosis (mostly with HD and T-cell NHL) have to be properly made, because of the very distinct prognosis and therapy.

Adult↗
PubMed1994

Chemical and spectroscopic studies of Cercidium praecox gum exudate.

The structure of the polysaccharide from Cercidium praecox (R&P) Harms gum exudate has been studied by Smith degradation, by sugar and methylation analyses, and by 13C NMR spectroscopy. The results showed a (1-->4)-xylan core. Some xylose residues are substituted at O-2 by alpha-D-glucuronic acid and 4-O-methyl-alpha-D-glucuronic acid residues. beta-D-Glucuronic acid is present, probably as terminal residues. The arabinose is present as alpha-L-furanose and beta-L-pyranose.

Arabinose↗
PubMed1994

Chronic recurrent multifocal osteomyelitis after acute lymphoblastic leukaemia.

We describe an 8 year old girl who developed chronic recurrent multifocal osteomyelitis (CRMO) in the ilium and clavicle. Treatment for an acute lymphoblastic leukaemia had been finished two months before. After antibiotic therapy, the clinical symptoms improved and no fresh lesions appeared. The aetiology of CRMO is unknown, but we feel that infection may precipitate an immunological reaction.

Anti-Bacterial Agents↗
PubMed1994

Chemical and 13C NMR studies of Enterolobium cyclocarpum gum and its degradation products.

A structural study of the gum exudate from Enterolobium cyclocarpum has been carried out using chemical methods and 13C NMR spectroscopy. The results reveal that the structure of this gum is essentially a beta-(1-->3)-galactan. Some galactoses are 6-O-linked and others also occur as terminal residues. There is evidence that supports the presence of alpha-L-arabinofuranose and beta-L-arabinopyranose. beta-D-Glucuronic acid may be present as terminal and internal residues, while the 4-O-methyl-alpha-D-glucuronic acid residues exist predominantly in internal positions.

Arabinose↗
PubMed1994

Efficacy of Chemical Disinfectants against Turbot Aquareovirus.

The susceptibility of turbot aquareovirus to five chemical agents was examined. Treatment with 5 mg of malachite green per liter or 500 mg of iodine per liter resulted in a 90% reduction in virus titer within 1 h. Complete inactivation within 5 min was obtained with 2% formalin, 42.5% isopropanol, or 15 mg of free available chlorine per liter. Lower concentrations of chlorine were ineffective.

Journal Article↗
PubMed1994

DNA content in non-Hodgkin's lymphoma. Comparison between flow cytometry and cytogenetics in fresh and paraffin-embedded tissue.

DNA content of 36-non-Hodgkin's lymphomas was analyzed by flow cytometry (FCM) and cytogenetics (CG), 21 in fresh and 15 in paraffin-embedded tissue. The results of both techniques were coincident in 60% of the fresh tissue samples and in 45% of the paraffin-embedded ones, the reason for this difference could be the poor resolution of DNA histograms from paraffin-embedded tissue. All samples judged as aneuploid by FCM were aneuploid also by CG. Some samples with a hyperdiploid population by CG gave a diploid population by FCM with a 'false' high DNA-synthesis (S) fraction. From a technical point of view, CG and FCM have to be performed on the same fresh tissue.

Cell Cycle↗