The distribution of agglutinins and lytic activity against Trypanosoma rangeli and erythrocytes in Rhodnius prolixus and Triatoma infestans tissue extracts and haemolymph

Haemolymph, heads, salivary glands, crops, midguts, hindguts, and Malpighian tubules from Rhodnius prolixus and Triatoma infestans were extracted in phosphate or Tris buffer saline with calcium, and tested for agglutination and lytic activities by microtitration against both vertebrateerythrocytes and cultured epimatigote forms of Trypanosoma rangeli. Haemagglutination activity against rabbit erythrocytes was found in the crop, midgut and hindgut extracts of T. infestans but only in the haemolymph of R. prolixus. Higher titres of parasite agglutinins were found in R. prolixus haemolymph than T. infestans, whilst the converse occurred for the tissue extracts. In addition, the extracts of T. infestans salivary glands, but not those of R. prolixus, showed a trypanolytic activity that was heat-inactivated and was not abolished by pre-incubation with any of the sugars or glycoproteins tested. T. infestans, which is refractory to infection by T. rangeli, thus appears to contain a much wider distribution of agglutinating and trypanolytic factors in its tissues than the more susceptible species, R. prolixus

The effect of acidic residues and amphipathicity on the lytic activities of mastoparan peptides studied by fluorescence and CD spectroscopy

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

New Insight into the Mechanism of Action of Wasp Mastoparan Peptides: Lytic Activity and Clustering Observed with Giant Vesicles

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Evaluation of Salmonella-Lytic Properties of Bacteriophages Isolated from Commercial Broiler Houses

Because of recent interest in bacteriophage therapy in poultry, information regarding the interaction of bacteriophages and potential host bacteria in the environment should be collected. The present studies were initiated with a rather typical commercial broiler integrator within the south-central United States to examine environmental Salmonella levels in two broiler complexes, attempt to isolate Salmonella-lytic bacteriophages, and elucidate a possible reason for differing apparent Salmonella prevalence. Significantly ( P<0.05) less Salmonella was isolated from houses in complex 1 ( 15/44 [ 34%] Salmonella-positive drag swabs) as compared to houses in complex 2 ( 22/24 [ 92%]). A total of seven Salmonella-lytic bacteriophages were isolated from Salmonella-positive environments, and two bacteriophages were isolated from a single Salmonella-negative house. During the initial bacteriophage isolation, individual bacteriophages did not replicate in the Salmonella host isolated from the same environment, and lysis of additional Salmonella hosts relied on high numbers of bacteriophage to be present. This suggests that the presence of these bacteriophages in the environment of a commercial broiler house had little to no effect on the presence of Salmonella. This study highlights the need to find additional bacteriophage sources, more effective isolation methods, and more innovative approaches to using bacteriophages to treat enteric disease.

Use of lytic bacteriophage for control of experimental Escherichia coli septicemia and meningitis in chickens and calves

A lytic bacteriophage, which was previously isolated from sewage and which attaches to the K1 capsular antigen, has been used to prevent septicemia and a meningitis-like infection in chickens caused by a K1+ bacteremic strain of Escherichia coli. Protection was obtained even when administration of the phage was delayed until signs of disease appeared. The phage was able to multiply in the blood. In newly borne colostrum-deprived calves given the E. coli orally, intramuscular inoculation of phage delayed appearance of the bacterium in the blood and lengthened life span. With some provisos there is considerable potential for this approach to bacterial-disease therapy.

Conformation and lytic activity of eumenine mastoparan: A new antimicrobial peptide from wasp venom

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

A conjugate of the lytic peptide Hecate and gallic acid: structure, activity against cervical cancer, and toxicity

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Construção de uma biblioteca de fragmentos de anticorpos monoclonais de galinhas com cadeia única (scFv) por phage display com reatividade cruzada para estirpes heterólogas do vírus da bronquite infecciosa aviária

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Lipid Peroxidation Is Associated with the Severity of Periodontal Disease and Local Inflammatory Markers in Patients with Type 2 Diabetes

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Anatomy and ontogeny of the pericarp of Pterodon emarginatus Vogel (Fabaceae, Faboideae), with emphasis on secretory ducts

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Structural and functional characterization of BnSP-7, a Lys49 myotoxic phospholipase A(2) homologue from Bothrops neuwiedi pauloensis Venom

BnSP-7, a Lys49 myotoxic phospholipase A, homologue from Bothrops neuwiedi pauloensis venom, was structurally and functionally characterized. Several biological activities were assayed and compared with those of the chemically modified toxin involving specific amino acid residues, the cDNA produced from the total RNA by RT-PCR contained approximately 400 bp which codified its 121 amino acid residues with a calculated pi and molecular weight of 8.9 and 13,727, respectively. Its amino acid sequence showed strong similarities with several Lys49 phospholipase A, homologues from other Bothrops sp, venoms. By affinity chromatography and gel diffusion, it was demonstrated that heparin formed a complex with BnSP-7, held at least in part by electrostatic interactions. BnSP-7 displayed bactericidal activity and promoted the blockage of the neuromuscular contraction of the chick, biventer cervicis muscle. In addition to its in vivo myotoxic and edema-inducing activity, it disrupted artificial membranes, Both BnSP-7 and the crude venom released creatine kinase from the mouse gastrocnemius muscle and induced the development of a dose-dependent edema. His, Tyr, and Lys residues of the toxin were chemically modified by 4-bromophhenacyl bromide (BPB), 2-nitrobenzenesulfonyl fluoride (NBSF), and acetic anhydride (AA), respectively. Cleavage of its N-terminal octapeptide was achieved with cyanogen bromide (CNBr), the bactericidal action of BnSP-7 on Escherichia coli was almost completely abolished by acetylation or cleavage of the N-terminal octapeptide, the neuromuscular effect induced by BnSP-7 was completely inhibited by heparin, BPB, acetylation, and CNBr treatment. The creatine kinase releasing and edema-inducing effects were partially inhibited by heparin or modification by BPB and almost completely abolished by acetylation or cleavage of the N-terminal octapeptide, the rupture of liposomes by BnSP-7 and crude venom was dose and temperature dependent. Incubation of BnSP-7 with EDTA did not change this effect, suggesting a Ca2+-independent membrane lytic activity. BnSP-7 cross-reacted with antibodies raised against B. moojeni (MjTX-II), B. jararacussu (BthTX-I), and B. asper (Basp-II) myotoxins as well as against the C-terminal peptide (residues 115-129) from Basp-II. (C) 2000 Academic Press.

Propolis and the immune system: a review

Propolis has been used empirically for centuries and it was always mentioned as an immunomodulatory agent. In recent years, in vitro and in vivo assays provided new information concerning its mechanisms of action, thus a review dealing with propolis and the immune system became imperative. This review compiles data from our laboratory as well as from other researchers, focusing on its chemical composition and botanical sources, the seasonal effect on its composition and biological properties, its immunomodulatory and antitumor properties, considering its effects on antibody production and on different cells of the immune system, involving the innate and adaptive immune response. In vitro and in vivo assays demonstrated the modulatory action of propolis on murine peritoneal macrophages, increasing their microbicidal activity. Its stimulant action on the lytic activity of natural killer cells against tumor cells, and on antibody production was demonstrated. Propolis inhibitory effects on lymphoproliferation may be associated to its anti-inflammatory property. In immunological assays, the best results were observed when propolis was administered over a short-term to animals. Propolis antitumor property and its anticarcinogenic and antimutagenic potential are discussed. Since humans have used propolis for different purposes and propolis-containing products have been marketed, the knowledge of its properties with scientific basis is not only of academic interest but also of those who use propolis as well. This review opens a new perspective on the investigation of propolis biological properties, mainly with respect to the immune system. (c) 2007 Elsevier B.V.. All rights reserved.

A synthetic peptide selectively kills only virulent Paracoccidioides brasiliensis yeasts

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Structural and functional characterization of two novel peptide toxins isolated from the venom of the social wasp Polybia paulista

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)