A new 5-alkylresorcinol glucoside derivative from Cybianthus magnus.

One new 5-alkylresorcinol glucoside (1) was isolated from leaves of Cybianthus magnus, along with 12 known compounds (2-13), isolated from four plants belonging to Myrsinaceae family. Their structures were determined on the basis of spectroscopic analysis and by comparison of their spectral data with those reported in the literature. Among the tested molecules, only compound 2 displayed a strong cytotoxic activity with IC50 values ranging between 22 and 100 µM for all cell lines tested. One new 5-alkylresorcinol glucoside (1) was isolated from leaves of Cybianthus magnus, along with 12 known compounds, isolated from four plants belonging to Myrsinaceae family (2, 3 isolated from C. magnus; 4-7, 10 and 11 isolated from Myrsine latifolia; 4, 8 and 9 isolated from Myrsine sessiflora; 6, 7, 10, 12 and 13 isolated from Myrsine congesta). Their structures were determined on the basis of spectroscopic analysis and by comparison of their spectral data with those reported in the literature. So far, only nine 5-alkylresorcinol glucosides were isolated from leaves of Grevillea robusta. Since resorcinols are known to exhibit strong cytotoxic activity, compounds 1 and 2 were tested against cell lines 3T3, H460, DU145 and MCF-7 for cytotoxicity in vitro and compounds 3-13 were tested for their antileishmanial activity. Compound 2 displayed a strong cytotoxic activity with IC50 values ranging between 22 and 100 µM for all tested cell lines. Compounds 3-13 were not active against Leishmania amazonensis amastigotes.

Spirolactone iridoids might be responsible for the antileishmanial activity of a Peruvian traditional remedy made with Himatanthus sucuuba (Apocynaceae).

Extracts of seven medicinal plants used specifically against cutaneous leishmaniasis in the Madre de Dios region of Peru were evaluated in vitro against promastigote and axenic amastigote forms of Leishmania amazonensis. One of them showed interesting leishmanicidal activities (IC(50)=5 microg/ml in amastigotes). Bio-guided isolation of the stem bark's ethanol extract of Himatanthus sucuuba (Spruce ex Müll. Arg.) Woodson (Apocynaceae) afforded the spirolactone iridoids isoplumericin and plumericin. The latter showed a reduction of macrophage infection similar to that of the reference drug Amphotericin B (IC(50)=0.9 and 1 microM, respectively). These findings validate the traditional use of Himatanthus sucuuba in the treatment of cutaneous leishmaniasis (Uta) in Peru.

A mouse IgG1 monoclonal antibody specific for N-glycolyl GM3 ganglioside recognized breast and melanoma tumors.

14F7 murine monoclonal antibody (MAb) is an IgG1 immunoglobulin that is generated by immunizing Balb/c mice with GM3(NeuGc) ganglioside hydrophobically conjugated with human very-low-density lipoproteins and in the presence of Freund's adjuvants. 14F7 MAb binds specifically to GM3(NeuGc), whereas neither N-glycolyl or N-acetyl gangliosides, nor a sulfated glycolipid, are recognized as assessed by enzyme-linked immunosorbent assay or immunostaining on thin layer chromatograms. Immunohistochemical studies in fresh tumor tissues showed that 14F7 MAb strongly recognized in antigen expressed in human breast and melanoma tumors.

Seasonal changes in photosynthesis of trees in the flooded forest of the Mapire River.

We studied the flood tolerance of five tree species growing in the flooded forest adjacent to the Mapire river, in SW Venezuela. Mean photosynthetic rate and leaf conductance were 11 &mgr;mol m(-2) s(-1) and 700 mmol m(-2) s(-1), respectively. Xylem water potential ranged from -0.08 to -1.15 MPa. Based on leaf gas exchange as a criterion of tolerance to flooding, two response patterns were identified: (1) decreasing photosynthetic rate with increasing flooding and leaf conductance (Psidium ovatifolium Berg. ex Desc., Campsiandra laurifolia Benth., Symmeria paniculata Benth. and Acosmium nitens (Vog.) Benth); and (2) independence of photosynthesis and leaf conductance from flooding (Eschweilera tenuifolia (Berg.) Miers.). In the first response pattern, declining photosynthetic rate with flooding may be interpreted as a sign of reduced flood tolerance, whereas the second response pattern may indicate increased flood tolerance. An increase in xylem water potential with depth of water column was found for all species (with the possible exception of P. ovatifolium), indicating that flooding does not cause water stress in these trees. Submerged leaves that had been under water for between four days and four months generally had photosynthetic rates and leaf conductances similar to those of aerial leaves, indicating maintenance of photosynthetic capacity under water. Daily positive oscillations in glucan content in submerged leaves of P. ovatifolium and C. laurifolia suggest that submerged leaves do not represent a sink for photosynthates produced by aerial leaves.

Generation of a murine monoclonal antibody specific for N-glycolylneuraminic acid-containing gangliosides that also recognizes sulfated glycolipids.

The P3 murine monoclonal antibody (MAb) was generated by immunizing BALB/c mice with NeuGcGM3 included into liposomes. The specificity of this MAb was defined by an enzyme-linked immunosorbent assay and immunostaining on thin-layer chromatograms. P3 MAb binds to NeuGc-containing gangliosides and was shown also to react with sulfated glycolipids. A preliminary immunohistochemical study showed that the P3 MAb was able to recognize antigens expressed in human breast tumors.

Epidemiological study of Hodgkin's disease in Cuba and Sweden.

In this register study the epidemiologic features of Hodgkin's disease (HD) in Cuba and Sweden during 1964-1981 are compared. HD in the adult (greater than or equal to 15 years of age) is more common in Sweden than in Cuba (age-standardized incidence rate 3.6 X 10(5) vs. 3.1 X 10(5) but for childhood HD the opposite is true (2.1 X 10(5) vs. 3.0 X 10(5). In both countries a male predominance is found. A decrease in the incidence of HD is noted only in the Swedish population after 1973. The study reveals a stable bimodal age incidence pattern in Sweden but a shift from a linear increasing to a bimodal incidence pattern in Cuba, which parallels the Cuban development from an agricultural to an industrialized country.

Clinical features of Hodgkin's disease in Cuba and Sweden.

A clinical study of 182 Swedish and 164 Cuban consecutive adult patients with Hodgkin's disease was performed comparing age, sex, histopathology, clinical stage, symptoms, and various laboratory tests. A bimodal age distribution was observed which was more pronounced in the Swedish series. A male/female ratio 1.8/1.0 in both samples was observed. Nodular sclerosis and Stage IA and IIA were more common in Swedish patients while in the Cuban, mixed cellularity and Stage IIIB and IVB dominated in patients below fifty years of age. The Swedish patients exhibited an age distribution similar to that found in other industrialized Western countries, while the Cuban patients had an age distribution pattern typical for countries with an intermediate epidemiological pattern.

Obtención de un anticuerpo monoclonal que identifica timocitos humanos / Obtention of a monoclonal antibody that identifies human thymocytes

El anticuerpo monoclonal (AcM) IOR-T7, del tipo IgM, es secretado por un hibridoma generado por la inmunización de ratones BALB/c con células de la línea de cultivo CEM y la fusión de los linfocitos esplénicos con el mieloma P3/x63.Ag8.6.5.3. Este AcM no reconoce, o lo hace en muy bajo porcentaje, las poblaciones celulares de la sangre periférica, mientras que identifica el 76 y el 79% de timocitos fetales y pediátricos, respectivamente, y las líneas celulares CEM y Molt-4, de origen T. El antígeno reconocido por este AcM parece estar relacionado con estadios tempranos de la ontogenia de los linfocitos humanos

Obtención de un anticuerpo monoclonal que identifica timocitos humanos / Obtention of a monoclonal antibody that identifies human thymocytes

El anticuerpo monoclonal (AcM) IOR-T7, del tipo IgM, es secretado por un hibridoma generado por la inmunización de ratones BALB/c con células de la línea de cultivo CEM y la fusión de los linfocitos esplénicos con el mieloma P3/x63.Ag8.6.5.3. Este AcM no reconoce, o lo hace en muy bajo porcentaje, las poblaciones celulares de la sangre periférica, mientras que identifica el 76 y el 79% de timocitos fetales y pediátricos, respectivamente, y las líneas celulares CEM y Molt-4, de origen T. El antígeno reconocido por este AcM parece estar relacionado con estadios tempranos de la ontogenia de los linfocitos humanos

Anticuerpos monoclonales contra el antígeno carcinoembrionario en ensayos inmunohistoquímico e inmunoquimicos / Monoclonal antibodies against carcinoembryonic antigen in immunohistochemical and immunochemical assays

En el presente trabajo se reporta la obtención de cinco clones de hibridomas de ratón, secretores de anticuerpos monoclonales que reconocen una preparación de antígeno carcinoembrionario (CEA). Durante el proceso de tamizaje y selección de estos clones, se empleó fundamentalmente un sistema de radioinmunoensayo, donde se compararon los sobrenadantes de cultivo o los ascitis tumorales con un antisuero policlonal de referencia, con respecto a su enlazamiento y especificidad por 125I-CEA. Los anticuerpos monoclonales seleccionados pertenecen a las clases G y M de inmunoglobulinas de ratón, y dos de ellos manifestaron bajo o ningún reconocimiento del antígeno de reactividad cruzada no específico (NCA). Los anticuerpos IOR-CEA 3 (IgM) e IOR-CEA 5 (IgG1) se estudiaron para su reconocimiento de tejidos fetales humanos, lesiones benignas de la mama, y cánceres de mama, pulmón y colon. El IOR-CEA 3 puede ser utilizado para estudios de confirmación histológica diagnóstica por técnica de inmunofluorescencia indirecta en tejido fresco. Los anticuerpos IOR-CEA 1 (IgG1) e IOR-CEA 2 (IgM) se ensayaron mediante diferentes combinaciones en un sistema ELISA para conocer su capacidad de detectar CEA purificado. Los resultados preliminares indican un adecuado nivel de reconocimiento cuando se utiliza como primer anticuerpo el antisuero policlonal anti-CEA de referencia y el monoclonal IOR-CEA 1 como segundo anticuerpo

Anticuerpos monoclonales contra el antígeno carcinoembrionario en ensayos inmunohistoquímico e inmunoquimicos / Monoclonal antibodies against carcinoembryonic antigen in immunohistochemical and immunochemical assays

En el presente trabajo se reporta la obtención de cinco clones de hibridomas de ratón, secretores de anticuerpos monoclonales que reconocen una preparación de antígeno carcinoembrionario (CEA). Durante el proceso de tamizaje y selección de estos clones, se empleó fundamentalmente un sistema de radioinmunoensayo, donde se compararon los sobrenadantes de cultivo o los ascitis tumorales con un antisuero policlonal de referencia, con respecto a su enlazamiento y especificidad por 125I-CEA. Los anticuerpos monoclonales seleccionados pertenecen a las clases G y M de inmunoglobulinas de ratón, y dos de ellos manifestaron bajo o ningún reconocimiento del antígeno de reactividad cruzada no específico (NCA). Los anticuerpos IOR-CEA 3 (IgM) e IOR-CEA 5 (IgG1) se estudiaron para su reconocimiento de tejidos fetales humanos, lesiones benignas de la mama, y cánceres de mama, pulmón y colon. El IOR-CEA 3 puede ser utilizado para estudios de confirmación histológica diagnóstica por técnica de inmunofluorescencia indirecta en tejido fresco. Los anticuerpos IOR-CEA 1 (IgG1) e IOR-CEA 2 (IgM) se ensayaron mediante diferentes combinaciones en un sistema ELISA para conocer su capacidad de detectar CEA purificado. Los resultados preliminares indican un adecuado nivel de reconocimiento cuando se utiliza como primer anticuerpo el antisuero policlonal anti-CEA de referencia y el monoclonal IOR-CEA 1 como segundo anticuerpo

Histochemical and ultrastructural study of human colon preneoplastic stages.

Fine structure and function are closely related in the cells of the different tissues. For this reason a comparative study combining histochemical techniques and scanning electron microscopy can result a potentially useful tool in the search for cell markers of preneoplastic stages of the colon mucosa. With this purpose, samples of normal colon mucosa, adenomatous polyps and adenocarcinomas obtained by colonoscopy were studied by histochemical techniques for the detection of epithelial mucosubstances and by scanning electron microscopy. Differences were shown in the architectural arrangement of the colon epithelium between the normal mucosa, the adenocarcinoma and the polyps studied, while between tubular an tubulovillous adenomas no marked differential ultrastructural features were found. Acid mucosubstances distribution pattern showed that sialomucin predominated in the colon mucosa harboring a carcinoma and in the tubulo-villous polyps as well as in the mucosa remote from adenocarcinoma and from the two cases of familial polyposis coli histologically considered as tubulo-villous adenomas. On the other hand tubular adenomas and normal mucosa showed a predominance of sulfomucin.

Ultrastructural study of glycogen containing cells in colonic adenocarcinomas and precancerous polypoid lesions.

A previous report of members of our group demonstrated, in most adenocarcinomas and some adenomatous polyps with areas of malignant transformation, the presence of glycogen in cells that failed to show the synthesis of ordinary mucosubstances. The presence of glycogen in non-differentiated epithelium of the digestive tract of embryos, where it precedes ordinary mucus secretion, has lead some authors to suggest that the changes to glycogen secretion that occurs in malignant colonic cells, reflects the general regression to a less differentiated level of structure and function. It is well established that patients with carcinomas of the colon classified as less differentiated or higher grade tumors have significantly less chance of cure and consequently a worse prognosis than patients with lower grade tumors. The present ultrastructural study of the morphological differentiation characteristics of the glycogen containing cells previously encountered, revealed a strong association of glycogen to undifferentiated cells of the colonic adenocarcinomas and precancerous polypoid lesions studied. This undoubtedly seems to encourage the testing for the presence of glycogen in routine procedures as a possible marker of diagnostic and prognostic significance.

Ammoniacal silver staining of lymph node cells. II. Reactive follicular hyperplasia and its relationship with Hodgkin's disease.

Lymph node biopsy specimens from 150 cases of reactive follicular hyperplasia, 52 cases of Hodgkin's disease and 30 cases of chronic lymphadenitis were studied. Clinical follow-up of cases for a period of two years at least was also considered. Formalin fixed and paraffin embedded tissues were stained with hematoxylin and eosin, and ammoniacal silver. Cytoplasmic accumulations of basic proteins were evidence in 30 out of 150 cases, but only 27 of these cases presented new lymph nodes with histological setting of Hodgkin's disease. The data suggest possible relationship between reactive follicular hyperplasia and Hodgkin's disease. However this relationship is not absolute as documented by two cases that being negative for the ammoniacal silver staining, were later diagnosed as Hodgkin's disease. Different types of atypical cells occurring in lymph nodes of reactive follicular hyperplasia were also studied. The potential use of ammoniacal silver staining in the early diagnosis of Hodgkin's disease is discussed.

Burkitt's lymphoma in Cuba. I. Clinical and morphological features and EBV association.

The first 7 cases of histologically and cytochemically confirmed Burkitt's lymphoma have recently been studied in Cuba. Some of them presented with facial bone involvement and high anti-Epstein-Barr virus (EBV) antibody titers characteristic of endemic African cases. Others showed features of nonendemic cases. The distribution of patients in these two groups may be in relation to the behavior of the healthy Cuban population with respect to the EBV virus.

Morphologic and cytochemical study of L929 cell variants with different metastasizing ability in C3HA/Hab mice.

A morphologic (phase-contrast, TEM and SEM) and cytochemical study was performed on L929 cell variants that show different malignant behavior and lung colonization ability in C3HA/Hab mice. The paper presents and discusses the correlation between enhanced lung colonization ability and the expression in culture of rounded, risen, less attached morphologies. Also, a diminution in the activity of mitochondrial enzymes and number of these cell organelles was found for the cell variant selected for enhanced lung colonization ability.

Ammoniacal silver staining of lymph node cells. I. its potential value for the diagnosis of Hodgkin's disease.

Lymph node biopsy specimens from 76 cases of Hodgkin's disease, 23 non-Hodgkin's lymphomas and 19 reactive affections of lymph nodes were studied. Formalin-fixed and paraffin embedded tissues were stained with hematoxylin and eosin, and post-formalin ammoniacal silver staining was used after BLACK and ANSLEY. The presence of basic protein accumulation in the cytoplasm of both Sternberg and Hodgkin cells was confirmed. To our knowledge it is the first report concerning the presence of these accumulations in the cytoplasma of atypical reticulum cells in Hodgkin's disease and in 3 of 7 cases of reactive follicular hyperplasia, in foreign body giant cells and in some lymphoblasts from 5 cases of Hodgkin's disease. The possibility of using the ammoniacal silver staining for identifying Sternberg cells is discussed. Also, it is proposed that when Sternberg cells are absent, the ammoniacal silver staining pattern of Hodgkin cells in an appropriate histological setting may be very indicative of Hodgkin's disease.