Detection of Leishmania causing visceral leishmaniasis in the Old and New Worlds by a polymerase chain reaction assay based on telomeric sequences.

We present a new polymerase chain reaction assay based on telomeric sequences of Leishmania donovani. When this assay was used in dilutions of purified L. donovani DNA, a strong amplification signal was observed with 1 fg of DNA. In a specificity test that used purified DNA from Old World and New World Leishmania, the assay recognized all parasites isolated from patients with visceral leishmaniasis, except for 2 isolates of Leishmania colombiensis from Venezuela and 1 isolate from Brazil. All Leishmania major and Leishmania tropica isolates tested were negative, except for one isolate in each species. We also used the assay on fresh and archive bone marrow samples recovered from Giemsa-stained slides and from dried blood stains.

Carcinoma hepato-celular en los Andes Venezolanos / Hepatocellular carcinoma in the Venezuelan Andes

Se estudian 31 casos de carcinoma hepatocelular (CHC), edad promedio de 56.9 años, 21 hombres y 10 mujeres. El grupo control edad promedio 52.7 años, 25 hombres y 6 mujeres. Las formas de presentación clínica fueron: franca 61.29 porciento; febril 12.90 porciento; metastásico 9.67 porciento; cirrótico 6,45 porciento incidental 3.22 porciento; hepatitis aguda 3.22 porciento; colestásico 3.22 porciento. Las pruebas hepáticas no reportaron diferencias estadísticamente significativas. El único test que demostró diferencias estadísticamente significativas fue la FA P<0.01 y las GO Vs TGP en CHC; apreciamos que las TGO tuvieron valores mayores que las TGP y esa diferencia es significativa P<0.001. De los CHC 77.41 porciento están sobre hígado no cirróticoy 22.59 porciento asociados a CH. En la serie los CHC sin cirrrosiis 57.14 porciento son HbsAg negativos y 17.85 porciento son positivos. En los CHC en hígado cirrótico, 21.42 porciento son HsbAg positivos y 3.57 porciento negativos. El total CHC HbsAg positivo es 39.28 porciento y 60.71 porciento son negativos, esta diferencia es 9X2 Yates) estadísticamente significativa P<0.02. La clasificación histológica demostró: trabeculares 21 (67.74 porciento), glandulares 8 (25.80 porciento), celulas claras 1 (3.23 porciento) y fibrolaminar 1 (3.23 porciento). La tasa de sobrevida global a 3meses 0.72 porciento. En nuestra región el CHC predomina en hígado no cirrótico, el HbsAg y cirrosis no son un factor esencial en su etiología

Formation of mouse red cell rosettes by "hairy" cells.

Rosette formation with mouse red cells was observed in the "hairy" cells of four cases of leukaemic reticuloendotheliosis. A similar observation was made on B-lymphocytes from chronic lymphoid leukaemia but the monocytes in monocytoid leukaemia did not form rosettes. This finding provides new evidence for the B-cell nature of the "hairy" cell.

Cytochemical profile of B and T leukaemic lymphocytes with special reference to acute lymphoblastic leukaemia.

The PAS and acid phosphatase reactions showed a different pattern of positivity in the cells of lymphoproliferative disorders according to their B or T cell nature. In B-cell leukaemias (chronic lymphocytic and prolymphocytic) a low proportion of lymphocytes gave a positive result with the acid phosphatase reaction, while the majority were PAS positive in granular form. In contrast, in the T-prolymphocytic and T-lymphoblastic leukaemias the acid phosphatase reaction was positive in the majority of cells, while the PAS reaction was only positive in a minority. The significance of these findings, particularly for the recognition of a distinct T-cell variant of acute lymphoblastic leukaemia, is discussed.