Tamoxifen as a potential antileishmanial agent: efficacy in the treatment of Leishmania braziliensis and Leishmania chagasi infections

The aim of this study was to evaluate the efficacy of tamoxifen in vivo in experimental models of cutaneous (CL) and visceral leishmaniasis (VL) caused by Leishmania braziliensis and Leishmania chagasi, respectively. Drug activity was assessed against intracellular amastigotes by treating infected macrophage cultures and evaluating the number of infected cells. In vivo efficacy of tamoxifen was tested in L. braziliensis-infected BALB/c mice and in L. chagasi-infected hamsters. Treatment with 20 mg/kg/day tamoxifen was administered for 15 days by the intraperitoneal route. Efficacy was evaluated through measurements of lesion size, parasite burden at the lesion site or liver and spleen and survival rate. Tamoxifen killed L. braziliensis and L. chagasi intracellular amastigotes with 50% inhibitory concentrations (IC(50)) of 1.9 +/- 0.2 and 2.4 +/- 0.3 mu M, respectively. Treatment of L. braziliensis-infected mice with tamoxifen resulted in significant reductions in lesion size and 99% decrease in parasite burden, compared with mock-treated controls. L. chagasi-infected hamsters treated with tamoxifen showed significant reductions in liver parasite load expressed as Leishman-Donovan units and 95% to 98% reduction in spleen parasite burden. All animals treated with tamoxifen survived while 100% of the mock-treated animals had died by 11 weeks after the interruption of treatment. Tamoxifen is effective in the treatment of CL and VL in rodent models.

Plasmodium vivax: Microsatellite analysis of multiple-clone infections

We used mixtures of genomic DNA from two genetically distinct isolates from Brazil, 42M and 312M, to investigate how accurately 12-locus microsatellite typing describes the overall genetic diversity and characterizes multilocus haplotypes in multiple-clone Plasmodium vivax infections. We found varying PCR amplification efficiencies of microsatellite alleles; for example, from the same 1:1 mixture of 42M and 312M DNA we amplified predominantly 312M-type alleles at 10 loci and 42M-type alleles at 2 loci. All microsatellite alleles were accurately scored in 1:0.5 and 1:0.25 312M:42M DNA mixtures, even when minor peak heights did not meet previously suggested criteria for minor allele detection in multiple-clone infections. Relative proportions of major and minor alleles were unaffected by multiple displacement amplification of template DNA prior to PCR-based microsatellite typing. Although microsatellite typing may detect minor alleles in clone mixtures, amplification biases may lead to inaccurate assignment of predominant haplotypes in multiple-clone P. vivax infections. (C) 2008 Elsevier Inc. All rights reserved.

Molecular characterization of Mycobacterium massiliense and Mycobacterium bolletii in isolates collected from outbreaks of infections after laparoscopic surgeries and cosmetic procedures

An outbreak of infections affecting 311 patients who had undergone different invasive procedures occurred in 2004 and 2005 in the city of Belem, in the northern region of Brazil. Sixty-seven isolates were studied; 58 were from patients who had undergone laparoscopic surgeries, 1 was from a patient with a postinjection abscess, and 8 were from patients who had undergone mesotherapy. All isolates were rapidly growing nonpigmented mycobacteria and presented a pattern by PCR-restriction enzyme analysis of the hsp65 gene with BstEII of bands of 235 and 210 bp and with HaeIII of bands of 200, 70, 60, and 50 bp, which is common to Mycobacterium abscessus type 2, Mycobacterium bolletii, and Mycobacterium massiliense. hsp65 and. rpoB gene sequencing of a subset of 20 isolates was used to discriminate between these three species. hsp65 and rpoB sequences chosen at random from 11 of the 58 isolates from surgical patients and the postinjection abscess isolate presented the highest degrees of similarity with the corresponding sequences of M. massiliense. In the same way, the eight mesotherapy isolates were identified as M. bolletii. Molecular typing by pulsed-field gel electrophoresis (PFGE) grouped all 58 surgical isolates, while the mesotherapy isolates presented three different PFGE patterns and the postinjection abscess isolate showed a unique PFGE pattern. In conclusion, molecular techniques for identification and typing were essential for the discrimination of two concomitant outbreaks and one case, the postinjection abscess, not related to either outbreak all of which were originally attributed to a single strain of M. abscessus.

Effects of the basic fibroblast growth factor and its anti-factor in the healing and collagen maturation of infected skin wound

PURPOSE: The infection is one of the main factors that affect the physiological evolution of the surgical wounds. The aim of this work is to evaluate the effects of fibroblast growth factor (FGFâ) and anti-FGFâ in the healing, synthesis and maturation of collagen when topically used on infected skin wounds of rats. METHODS: An experimental study was perfomed in 60 male Wistar rats. All animals were divided in two groups (A and B). Each group was divided in three subgroups A1, B1; A2, B2 and A3, B3. After anesthesia with pentobarbital, two open squared wounds (1cm2), 4cm distant to each other, were done in the dorsal skin of all the rats. In group A (n=30) the wounds were contaminated with multibacterial standard solution, and in group B(n=30) the wounds were maintained sterile. These wounds were named F1 (for inflammation analysis) and F2 (for collagen study). The open wounds of A1 and B1 rats were topically treated with saline solution, A2 and B2 were treated with FGFâ and subgroups A3 and B3 were treated with FGFâ and anti-FGFâ. The rats were observed until complete epitelization of F2 wounds for determination of healing time and the expression of types I and III collagen, using Picro Sirius Red staining. Inflammatory reaction in F1 wounds was studied using hematoxilineosin staining. The three variable was measured by the Image Pro-Plus Média Cybernetics software. The statistical analysis was performed by ANOVA and Tukey test, considering p<0.05 as significant. RESULTS: It was observed that infection retarded significantly (p<0.05) the time of wound scarring and the topical application of FCFb reverted the inhibition of healing caused by bacteria. The inflammatory reaction was greater in the subgroup B2 than in B1 and A3, and the difference was significant (p<0.05). It was observed greater expression of type I collagen in all the subgroups treated with FCFb, when compared with the untreated subgroups. Type III collagen was significantly decreased in wounds of B3 rats, comparing to the other subgroups. CONCLUSIONS: The FCFb accelerated the healing of open infected wounds and contributed with maturation of collagen, enhancing the type I collagen density. The anti-FCFb antibody was able to attenuate the production of both type I and III collagen

Comparative study between the effects of hyaluronic acid and acid galactan purified from eggs of the mollusk Pomacea sp in wound healing

To compare the effect of hyaluronic acid (HA) and of AG on the healing of intestine wounds. Methods: The semi-purified extract of the eggs of the mollusc was obtained by fractionation with ammonium sulfate and purification for ion-exchange chromatography. The obtained galactans were eluted in water (neutral galactan) and in 0.1 and 0.2M NaCl (acidic galactans). The in vivo study was performed with 45 “Wistar” rats, separated in three groups (n=15). Solutions containing HA 1%, GA 1% or saline solution 0,9%, was placed topically on the sutures of wounds in the small intestine of the rats. After 05, 10 and 21 days the animals were sacrificed and biopsy of the healing tissue was done. Results: The hystologic grading was more significant for HA and AG groups when compared to the group C. AG stimulated the appearance of macrophages, giant cells and increase in the concentration of collagen in the area of the wound when compared to HA. Conclusion: The topical use of GA in intestinal wounds promoted the anticipation of events that are important in the wound healing

HEMATOLOGICAL ASSESSMENT IN FOUR BRAZILIAN TELEOST FISH WITH PARASITIC INFECTIONS, COLLECTED IN FEEFISHING FROM FRANCA, São Paulo, BRAZIL

The effects of parasitic infections in condition factor, hematocrit, hemoglobin, mean corpuscular hemoglobin concentration (MCHC), and leucocytes and thrombocytes distribution in Piaractus mesopotamicus, Leporinus macrocephalus, hybrid tambacu (P. mesopotamicus x Colossoma macropomum and Brycon amazonicus collected in feefishing from Franca, São Paulo, Brazil were evaluated. Parasitized tambacu and L. macrocephalus had higher (p<0.05) condition factor than unparasitized fish. However, the contrary occurred in P. mesopotamicus and B. amazonicus. Changes in the hematocrit, hemoglobin and MCHC were not related to parasitism. Parasitic infections did not cause effect on leucocytes and thrombocytes percentage (p>0.05) of tambacu. In P. mesopotamicus parasitized by Monogenea Anacanthorus penilabiatus and dinoflagellate Piscinoodinium pillulare, increase in monocytes and decrease in thrombocytes percentage (p<0.05) were found. However, the same parasitic association in L. macrocephalus caused a decrease in lymphocytes percentage accompanied by increase in neutrophils percentage (p<0.05). In B. amazonicus, infection by Ichthyophthirius multifiliis, P. pillulare and monogeneans caused increase in neutrophils percentage.

Soil CO2 emission and its relation to soil properties in sugarcane areas under Slash-and-burn and Green harvest

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Observations on helminth infections of free-living and captive rheas (Rhea americana) in Brazil

The present work describes helminth infection of eight free-living and 12 captive rheas (Rhea americana) from, respectively, Pantanal of Mato Grosso do Sul State, and Jaboticabal, São Paulo State, Brazil. Captive birds were young and had a high mortality rate, while free-living birds were adult and apparently healthy. Infections were evaluated by post-mortem examination of internal organs and recovery of helminths using standard parasitological procedures. Seven species of nematodes (Sicarius uncinipenis, Torquatoides crotophaga, Deletrocephalus dimidiatus, D. cesarpintoi, Paradeletrocephalus minor, Capillaria venteli and Dicheilonema rheae) and two species of cestodes (Houttuynia struthionis and Chapmania tauricolis) were identified. P. minor, which inhabits the large intestine, was the most common helminth in free-living birds (63.9%). In captive rheas, a mean parasitic load of 173 helminths per host was found. The gizzard of these birds was the most parasitized organ and S. uncinipenis was most common (92.5%). Parasitism of free-living and captive birds and associated pathology are discussed. (c) 2005 Published by Elsevier B. V.

Natural infections with filarioidea nematodes in Hydrochaerus hydrochaeris in the floodplain of Mato Grosso do Sul, Brazil

Foram coletados 570 nematódeos Filaroidea de 36 capivaras, sacrificadas entre 1989 e 1996, onze jovens menores que seis meses e 25 adultas, provenientes da região do pantanal do Mato Grosso do Sul (Paiaguás). Cento e setenta e seis (176) espécimes de Yatesia hydrochoerus foram encontrados nas fáscias dos músculos esqueléticos, principalmente da região do obliquus externus abdominis e na face interna dos membros posteriores e trezentos e noventa e quatro (394) espécimes de Cruorifilaria tuberocauda foram coletados das artérias renais (380) e das artérias pulmonares (14) dos animais.

Neospora caninum infection in birds: experimental infections in chicken and embryonated eggs

Neospora caninum causes economical impact in cattle-raising farms since it is implicated as the major cause of bovine abortions. Although infection by the parasite has been widely described in mammals, the role of birds in its life-cycle is still obscure. Therefore, this work aimed to evaluate the infection by N. caninum in different chicken models. Experimental infections were conducted in 7-day-old chicks, laying hens and embryonated eggs, where samples were analysed for parasite burden, IgG antibodies and lesions promoted. Chickens demonstrated an asymptomatic infection, although with seroconversion and systemic replication of the parasite. In laying hens, no signs of vertical transmission were observed. However, embryonated eggs inoculated by the allantoic cavity route demonstrated susceptibility to infection, with mortality rates around 50% independent of the inoculum dose. Additionally, dogs became infected after ingestion of different amounts of inoculated eggs, producing either oocysts or specific IgG antibodies. The results herein presented demonstrate that chickens may be intermediate hosts of N. caninum and that embryonated eggs could be a useful model to study the parasite's biology.

Phenotypical characterization and adhesin identification in Escherichia coli strains isolated from dogs with urinary tract infections

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

The hamster cheek pouch: an immunologically privileged site suitable to the study of granulomatous infections

A bolsa jugal do hamster (BJH) é uma invaginação da mucosa oral, caracterizada histologicamente como semelhante a pele. Nesse estudo nós descrevemos algumas de suas características anatômicas, histológicas e embriológicas e comentamos sobre sua propriedade como local imunologicamente privilegiado, considerando a ausência de drenagem linfática e o reduzido número de células de Langerhans. Apresentamos também os resultados obtidos quando da inoculação de micobacterias (BCG, Mycobacterium tuberculosis e Mycobacterium leprae) e do fungo Paracoccidioides brasiliensis na bolsa jugal. Comparada com as lesões provocadas em outras localizações e, à exceção do BCG, as lesões induzidas na bolsa são menores e de maior duração e, mesmo quando granulomatosas, incapazes de controlar a multiplicação do agente; nos casos em que houve o desenvolvimento da resposta imune, ele se fez tardiamente e foi acompanhado pela redução do número de parasitas nas lesões. Essas observações apontam a bolsa jugal do hamster como um local de escolha para o estudo sobre a participação da resposta imune no desenvolvimento e modulação das doenças infecciosas e dos granulomas.

Forest natural regeneration and biomass production after slash and burn in a seasonally dry forest in the Southern Brazilian Amazon

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

Intestinal healing in rats submitted to ethanol ingestion

OBJETIVO: Estudar o efeito do alcoolismo no processo de cicatrização intestinal e suas complicações pós-operatórias em ratos. MÉTODOS: Cento e sessenta ratos foram divididos em dois grupos: tratado e controle. O controle recebeu água, enquanto o tratado etanol a 30%. Após 180 dias foram realizadas colotomia, seguida de anastomose. Após os animais foram divididos em quatro subgrupos de 20 ratos para estudo nos seguintes momentos: 4º, 7º, 14º e 21º pós-operatório. Os parâmetros analisados foram: ganho de peso, força de ruptura, hidroxiprolina tecidual, complicações pós-operatórias e estudo histopatológico. RESULTADOS: O ganho de peso foi superior no grupo controle (p<0,05). Após agrupamento dos momentos a força de ruptura foi superior no controle (p<0,05). Não houve diferença quanto à histopatologia e hidroxiprolina. Houve cinco infecções de incisão no grupo tratado, enquanto no controle ocorreram duas (p>0,05). Houve nove fístulas no grupo tratado, enquanto no controle duas (p<0,05). Ocorreram sete mortes no grupo tratado e apenas três no controle (p>0,05). CONCLUSÕES: No grupo tratado ocorreu um processo de subnutrição evidenciado pelo menor ganho de peso. Piora na cicatrização intestinal, indicada pela menor força de ruptura. Ocorreu um maior número de complicações pós-operatórias no grupo tratado.

Fungal infections of the mucous membrane

A clinical review of three potentially severe fungal diseases, which are characterized in many cases by mucosal involvement, is presented. They are paracoccidioidomycosis, histoplasmosis, and mucormycosis. Mucosal involvement for paracoccidioidomycosis and rhinocerebral mucormycosis is frequent. Thus, oral involvement may provide early clue for diagnosis. In paracoccidioidomycosis, the mucosal lesion classically shows superficial ulcers with granular appearance and hemorrhagic points, usually on lips, palate, and jugal mucosa. In mucormycosis, necrosis of the palate followed for purulent discharge is a hallmark of rhinocerebral disease. Treatment with amphotericin B desoxycholate or the new second-generation triazoles is highly efficacious.