Burkitt-like lymphoma in an infant: a case report

Childhood non-Hodgkin's lymphomas, including Burkitt and Burkitt-like, are rarely diagnosed in infants. A case of B-cell lymphoma in a 13-month-old girl with extensive abdominal disease, ascites, pleural effusion, and tumor lysis syndrome is reported. Phenotypic analysis showed a germinal center B-cell phenotype, and a B-cell clonality was confirmed by polymerase chain reaction. There was no evidence of Epstein-Barr and HIV infection. The case herein reported emphasizes the need for considering the diagnosis of lymphoma even in very young children.

Junça (Cyperus esculentus Linné), bulbilho consumido no Maranhão e que possui bom valor nutritivo.

Junça (Cyperus esculentus Linné), edible bulb of Maranhão that has good nutritional value. F. Marx, and W. E. Kerr.Bulbs of junça one sold in the streets oF Sao Luis, Ma, Brazil, as a delicacy. It has good nutritional value like: 6-10% protein, 6.95 to 9,32mg/lOOg of alpha-tocoferol, 1.20 to 2.52mg/100 of gama-tocoferol, 424.4mg/100g of K and 3,5mg/100g of Zn.Our samples had 1.4% glicose and 16.0% of saccharose. Literature is revised and this bulb is recommended for human consumption.

Lankesterella alencari n. sp., a toxoplasma-like organism in the central nervous system of Amphibia (Protozoa, Sporozoa)

Lankesterella alencari n. sp. a Sporozoa that occur in the blood and CNS of the South American frog Leptodactylus acellatus is described. Since the tissue forms of this parasite have been previously reported as belonging to the genus Toxoplasma, we attempted in fection of 2 species of amphibia (Bufo marinus an dLeptodactylus ocellatus) with a Toxoplasma strain of human origen; inoculation was by intraperitoneal injection of parasite-containing ascitic fluid from infected mice. Attempt of experimental inoculation of the parasite found in the CNS of L. ocellatus in a highly susceptible host (mice) was unsuccessful. These results suggest that Toxoplasma does not occur naturally in the amphibia; be related to Toxoplasma is excluded. The following genera of haematozoa found in brazilian amphibia have been considered briedfly: Haemobartonella, Cytamoeba, Dactylosoma, Hepatozoon and Trypanosoma.

A medium for inducing conversion of Histoplasma capsulatum var. capsulatum into its yeast-like form

Histoplasma capsulatum var. capsulatum is a dimorphic fungus that, under special conditions, converts from its more common mycelial form to a yeast-like form. Achieving this conversion, however, has been problematical for researchers. The present study tested conversion rates in ten Histoplasma capsulatum var. capsulatum strains using seven culture media, four of wich were conventional and three novel. One of our novel media, MLGema, induced complete conversion, of two strains within five days of incubation at 35 degrees centigrades, and of all strains that eventually converted by the time of the second subculturing transfer, under defined experimental conditions. MLGema is also inexpensive and easy to produce.

Acetylated alpha-tubulin in Trypanosoma cruzi: immunocytochemical localization

We have used monoclonal antibodies specific for acetylated and non-acetylated alpha-tubulin to localize microtubules containing acetylated alpha-tubulin in all developmental forms of the life cycle of Trypanosoma cruzi. This was demonstrated using immunofluorescence and by transmission electron microscopy of thin sections, negative stained cells, and replicas of whole Triton X-100 extracted cells immunolabeled with antibody-gold complex. The antibody specific for acetylated alpha-tubulin (6-11B-1) binds to the flagellar, as well as to the sub-pellicular microtubules. The extent of labeling of the sub-pellicular microtubules with the monoclonal antibody recognized alpha-acetylated tubulin was smaller than that observed with the antibody which recognizes all tubulin isoforms. In relation to the developmental forms, the extent of labeling of the microtubules with antibody 6-11B-1 was larger in epimastigote and trypomastigote than in amastigote forms. Incubation of the parasites for 1 h at 0º C or in the presence of either colchicine or vinblastine did not interfere with the sub-pellicular microtubules. These observations, in agreement with those reported for Trypanosoma brucei brucei (Schneider et al., 1987; Schulze et al., 1987; Sasse per cent Gull, 1988) indicate that the sub-pellicular microtubules of trypanosomatids represent stable microtubules containing acetylated alpha-tubulin (or the alpha 3-tubulin isotype).

An inhibition ELISA to determine alpha macroglobulin levels in mouse plasma

A sensitive method for quantifying mouse plasma alpha-macroglobulins (AM) using an inhibition ELISA is described. AM are important plasmaproteinase inhibitors that possibly act also as immunomodulatory molecules. The standard protocol develope in our experiments involves coating well with 10 µg/ml A2M in carbonate buffer, followed by incubation with a 1:1 (v/v) mixture of the plasma to be tested (diluted 1/1000) and goat anti-AM (diluted 1/1250). This is followed by further incubation, first with the enzyme-conjugated antibody and with the substrate prior to the reading of absorbance levels of the reaction products. Standard curve samples must be included in each plate, employing known amounts of the purified Murine Alpha-2-Macroglobulin (MuA2M) used for coating, with concentrations ranging from 0.001 to 10 µg/ml. Using test samples in triplicates and a 6-point standard curve in a single ELISA plate, 25 plasma samples can be tested accurately. The method offers an useful tool for establishing AM levelsin small samples of mouse plasma.

The cave-like sense organ in the antennae of Triatominae bugs

In the second segment of the antennae of haematophagous reduviids an unusual cave-like organ is found the function os which was investigated in Triatoma infestans. the morphology of the organ makes it difficult to ascribe it to a mechno- or chemoreceptive function, but shows some characteristics shared with thermoreceptors of other animals. The electrical activity of sense cells was recorded in the presence of stimuli that evoke behavioural responses in this species, i.e. warm, CO2, lactic and butyric acids at different concentrations. The three compounds tested failed to evoke a response at all concentrations assayed. Only thermal stimulation evinced a clear modification in the electrical activity of the sense cells.Both the morphological and electrophysiological findings support a thermoreceptive finding, habitat selection and circadian synchronization.

Transfer of toxin genes to alternate bacterial hosts for mosquito control

Mosquitoes are vector of serious human and animal diseases, such as malaria, dengue, yellow fever, among others. The use of biological control agents has provide an environmentally safe and highly specific alternative to the use of chemical insecticides in the control of vector borne diseases. Bacillus thuringiensis and B. sphaericus produce toxic proteins to mosquito larvae. Great progress has been made on the biochemical and molecular characterization of such proteins and the genes encoding them. Nevertheless, the low residuality of these biological insecticides is one of the major drawbacks. This article present some interesting aspects of the mosquito larvae feeding habits and review the attempts that have been made to genetically engineer microorganisms that while are used by mosquito larvae as a food source should express the Bacillus toxin genes in order to improve the residuality and stability in the mosquito breeding ponds.

Cloning, Expression and Toxicity of a Mosquitocidal Toxin Gene of Bacillus thuringiensis subsp. medellin

Bacillus thuringiensis (Bt) subsp. medellin (Btmed) produces parasporal crystalline inclusions which are toxic to mosquito larvae. It has been shown that the inclusions of this bacterium contain mainly proteins of 94, 68 and 28-30 kDa. EcoRI partially digested total DNA of Btmed was cloned by using the Lambda Zap II cloning kit. Recombinant plaques were screened with a mouse policlonal antibody raised against the 94 kDa crystal protein of Btmed. One of the positive plaques was selected, and by in vivo excision, a recombinant pBluescript SK(-) was obtained. The gene encoding the 94 kDa toxin of Btmed DNA was cloned in a 4.4 kb DNA fragment. Btmed DNA was then subcloned as a EcoRI/EcoRI fragment into the shuttle vector pBU4 producing the recombinant plasmid pBTM3 and used to transform by electroporation Bt subsp. israelensis (Bti) crystal negative strain 4Q2-81. Toxicity to mosquito larvae was estimated by using first instar laboratory reared Aedes aegypti, and Culex quinquefasciatus larvae challenged with whole crystals. Toxicity results indicate that the purified inclusions from the recombinant Bti strain were toxic to all mosquito species tested, although the toxicity was not as high as the one produced by the crystal of the Btmed wild type strain. Poliacrylamide gel electrophoresis indicate that the inclusions produced by the recombinant strain Bti (pBTM3) were mainly composed of the 94 kDa protein of Btmed, as it was determined by Western blot