Cutaneous Resistance to Evaporative Water Loss in Brazilian Rhinella (Anura: Bufonidae) from Contrasting Environments

Influenced by taxonomic position. For example, bufonids are regarded as exhibiting a permeable skin that seems typical for terrestrial anurans. However, this assumption is supported by information on only four bufonid species; therefore, the enormous ecological diversity of the family remains poorly Investigated. To assess whether variation in R(s) within related bufonids correlates with environmental aridity, we measured area-specific rates of EWL of two Brazilian populations of Rhinella granulosa (previously Bufo granulosus), one from the Atlantic Forest and other from the semi-arid Caatinga, and compared both with the forest species R. ornato. Rhinella granulosa from the Atlantic Forest had higher cutaneous resistance than conspecifics from Caatinga and R. ornata. Rhinella ornato presented the lowest cutaneous resistance values. However, Rs were very close to zero In all three populations. We conclude that enhanced Rs is not part of the suite of traits allowing R. granulosa to exploit the Caatinga, and that variation in R(s) within bufonids may relate to traits other than water conservation. Some Information on microhabitat occupation and ventral skin morphology supports the idea that exceptional abilities for detecting and taking up water may be the key factors enhancing the survival of R. granulosa, and possibly other bufonids, in xeric environments.

Genetic and Functional Evidence Implicating DLL1 as the Gene That Influences Susceptibility to Visceral Leishmaniasis at Chromosome 6q27

Background. Visceral leishmaniasis (VL) is caused by Leishmania donovani and Leishmania infantum chagasi. Genome-wide linkage studies from Sudan and Brazil identified a putative susceptibility locus on chromosome 6q27. Methods. Twenty-two single-nucleotide polymorphisms (SNPs) at genes PHF10, C6orf70, DLL1, FAM120B, PSMB1, and TBP were genotyped in 193 VL cases from 85 Sudanese families, and 8 SNPs at genes PHF10, C6orf70, DLL1, PSMB1, and TBP were genotyped in 194 VL cases from 80 Brazilian families. Family-based association, haplotype, and linkage disequilibrium analyses were performed. Multispecies comparative sequence analysis was used to identify conserved noncoding sequences carrying putative regulatory elements. Quantitative reverse-transcription polymerase chain reaction measured expression of candidate genes in splenic aspirates from Indian patients with VL compared with that in the control spleen sample. Results. Positive associations were observed at PHF10, C6orf70, DLL1, PSMB1, and TBP in Sudan, but only at DLL1 in Brazil (combined P = 3 x 10(-4) at DLL1 across Sudan and Brazil). No functional coding region variants were observed in resequencing of 22 Sudanese VL cases. DLL1 expression was significantly (P = 2 x 10(-7)) reduced (mean fold change, 3.5 [SEM, 0.7]) in splenic aspirates from patients with VL, whereas other 6q27 genes showed higher levels (1.27 x 10(-6) < P < .01) than did the control spleen sample. A cluster of conserved noncoding sequences with putative regulatory variants was identified in the distal promoter of DLL1. Conclusions. DLL1, which encodes Delta-like 1, the ligand for Notch3, is strongly implicated as the chromosome 6q27 VL susceptibility gene.

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.

COM-Poisson cure rate survival models and an application to a cutaneous melanoma data

In this paper, we develop a flexible cure rate survival model by assuming the number of competing causes of the event of interest to follow the Conway-Maxwell Poisson distribution. This model includes as special cases some of the well-known cure rate models discussed in the literature. Next, we discuss the maximum likelihood estimation of the parameters of this cure rate survival model. Finally, we illustrate the usefulness of this model by applying it to a real cutaneous melanoma data. (C) 2009 Elsevier B.V. All rights reserved.

Hematoporphyrin-based photodynamic therapy for cutaneous squamous cell carcinoma in cats

Photodynamic therapy (PDT) using a haematoporphyrin derivative (Photogem (R), General Physics Institute and clustes Ltda) as photosensitizer and light emitting diodes (LEDs) as the light source was evaluated in 12 cats with cutaneous squamous cell carcinoma. Lesions were illuminated with LEDs, (300 J/cm for 30 min) 24 h after the administration of the photosensitizer. Clinical responses were classified as complete disappearance of the tumour with total re-epithelialization; partial response (a reduction greater than 50%); and no response (less than 50% reduction). Tumours localized to the pinna treated with one (n = 3) or two (n = 4) applications of PDT yielded no response. Highly invasive tumours of the nose and nasal planum also showed no response, after two treatments (n = 2). A combination of PDT and surgery was performed in three cases. Two cats showed partial response and one complete response with one application of therapy 30 days after nasal surgery. Small and noninfiltrative lesions (n = 3) of the nasal planum showed a PR with one application (n = 2) and a CR with two applications (n = 1). This study shows that PDT using Photogem (R) and LEDs can provide local control of low-grade feline squamous cell carcinoma. The addition of PDT to surgery in more invasive cases may help prevent recurrence.

Density of sand flies (diptera: psychodidae) in domestic and wild animal shelters in an area of visceral leishmaniasis in the state of Rio Grande do Norte, Brazil

XIMENES, Maria de Fátima Freire de Melo; SOUZA, Maria de Fátima de; CASTELLON, Eloy Guilhermo. Density of sand flies (Diptera: Psychodidae) in domestic and wild animal shelters in an area of visceral Leishmaniasis in the State of Rio Grande do Norte, Brazil. Memorias do Instituto Oswaldo Cruz, Rio de Janeiro, v.94, n.4, p.427-432, jul./ago. 1999. Disponivel em: Acesso em: 4 out. 2010.

Estudo clínico-laboratorial e histopatológico de cães naturalmente infectados por Leishmania chagasi com diferentes graus de manifestação física

Canine Visceral Leishmania (CVL) is an important zoonotic disease that has a world wide distribution and has a large impact on public health on the American Continent, especially in Brazil, where the nature of endemic diseases in humans affects a large part of the nation. The influence of the prevalence of CVL in the increased rate of human cases in endemic areas and in the unleashing of epidemic outbreaks shows the need for a more profound understanding, that would generate significant advances in the current measures used to control the reservoirs of sickness that are practiced by the Programa Nacional de Vigilância e Controle da Leishmaniose Visceral. The present work describes and compares the clinical-laboratorial and histopathological findings of twenty-three dogs that were naturally infected by Leishmania chagasi, from endemic areas in metropolitan Natal, Rio Grande do Norte, Brazil. These animals, that were selected and given physical and serological exams (IFI and ELISA rK-39), were classified according to the degree of clinical severity and had blood samples drawn (whole blood and serum) for a complete hemogram and a coagulogram to be done as well as biochemical tests for kidney and liver function. The confirmation of infection by L. chagasi was done after the euthanasia of the animals, through the direct demonstration of the parasite in the impression of the spleen and liver crowned with GIEMSA and through a cultivation by means of NNN/Schneider. According to the clinical evaluation, the animals were classified as asymptomatic (7), oligosymptomatic (7) and polysymptomatic (9). Among the animals that were chosen to be autopsied, there were 2 asymptomatic, 3 oligosymptomatic and 3 polysymptomatic, for the purpose of studying their histopathology, having collected fragments of the spleen, liver, kidneys and skin and were fixed in 10% tamponed formol. The comparison between the average parameters of the clinical-laboratory tested animals in the groups was done through the Student t test (a<0.05). The main clinical signals observed were lymphadenomegaly, alopecy, dermatitis, exfoliation, cutaneous ulcers, onicogriphosis and emaciation. The main clinical-laboratorial alterations established, mainly in the polysymptomatic group, were anemia, hyperproteinemia, hyperglobulinemia, alterations in the albumin/globulin ratio and increased ALT activity. Renal alterations were not verified (urea and creatinine levels were normal). Thrombocytopenia was observed in three clinical groups. However, the other indicators of coagulation function (TAP and TTPA) did not have abnormal variations. There were inflammatory infiltrations and leishmania amastigotes in the skin of polysymptomatic dogs, however, they were not found in the skin of asymptomatic animals. Hypertrophy and hyperplasia of the phagocyte mononuclear system, leishmania amastigote parasites were found in the macrophages, extramedullary hematopoiesis and degenerative alterations were detected in the spleen and liver of 8 of the animals submitted to histopathological exams. In accord with these results, it was demonstrated that the expected alterations in the hematological and biochemical parameters in function of their viscerotropic nature of CVL are mainly observed in the more advanced stages of the disease. The absence of inflammatory infiltration and parasite load in the skin suggest that infected animals without symptoms may have an importance irrelevant to the infectiousness of the vector

Cutaneous Basophilia in the Resistance of Goats to Amblyomma cajennense Nymphs after Repeated Infestations

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Guinea Pigs Develop Cutaneous Basophilia after Repeated Infestations by Nymphs of the Tick Amblyomma triste

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

Immune response pattern of the popliteal lymph nodes of dogs with visceral leishmaniasis

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

VISCERAL LEISHMANIASIS IN A CAPTIVE CRAB-EATING FOX CERDOCYON THOUS

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

Sandfly fauna in an area endemic for visceral leishmaniasis in Aracaju, State of Sergipe, Northeast Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influence of extracts of Stryphnodendron polyphyllum Mart. and Stryphnodendron obovatum Benth. on the cicatrisation of cutaneous wounds in rats

Stem bark of the two species Stryphnodendron polyphyllum Mart. and Stryphnodendron obovatum Benth., Leguminosae, was investigated for wound healing, antibacterial and antioxidant activity. These plants contain 12 and 19% tannins in their stem bark, respectively, and are widely used in traditional medicine in Brazil. The total content of phenolics of the crude extract (CE) of Stryphnodendron obovatum was 76.95 +/- 2.98% (CV = 3.87%) and of the ethyl-acetate fraction (EAF) was 89.13 +/- 0.34% (CV = 0.38%); whereas in Stryphnodendron polyphyllum the CE phenolics content was 51.62 +/- 1.53% (CV = 2.96%) and the EAF phenolics content was 59.00 +/- 1.91% (CV = 3.24%). The tannin content of CE from Stryphnodendron obovatum [36.58 +/- 0.35% (CV = 0.98%)] was about 11% higher than in CE from Stryphnodendron polyphyllum [25.43 +/- 0.96% (CV = 3.77%)]. The difference between the species was even greater in the EAF: in Stryphnodendron obovatum the EAF phenolics content was 55.01 +/- 0.36% (CV = 0.65%), whereas in Stryphnodendron polyphyllum the content was 36.16 +/- 0.42% (CV = 1.16%). The healing effect of ointments containing 2.5% crude lyophilised extract (PCE) and 2.5% ethyl-acetate lyophilised fraction (PEA) of the stem bark of Stryphnodendron polyphyllum and Stryphnodendron obovatum was studied in cutaneous wounds of Wistar((R)) rats after 4, 7 and 10 days of treatment. Epithelial cell proliferation in the area of re-epithelialisation of the wounds was evaluated by counting the metaphases blocked by vincristine sulfate. With PCE an increase in epidermal growth was observed after 4 and 7 days of treatment with Stryphnodendron polyphyllum, and after 7 and 10 days of treatment with Stryphnodendron obovatum. Wounds treated with PEA of Stryphnodendron obovatum showed increased epidermal growth only 4 days after the treatment, for Stryphnodendron polyphyllum, epidermal growth was observed after 4 and 7 days of treatment. Both the CE and the EAF fractions of Stryphnodendron polyphyllum and Stryphnodendron obovatum showed antibacterial activity against Staphylococcus aureus with MIC values of 125 and 250 mu g/ml, respectively. Gram-negative bacteria tested were not inhibited by extracts and fractions at concentrations > 1000 mu g/ml. The antioxidant activity through reduction of the DPPH radical in TLC, confirmed the anti-radical properties of these extracts in both species. CE and EAF of both species showed a radical scavenging activity (RSA) and protected DPPH from discolouration, already at 0.032 mu g/ml. The extract from Stryphnodendron polyphyllum were more effective than those Stryphnodendron obovatum, although the former had a lower tannin content. (c) 2005 Elsevier B.V.. All rights reserved.

In Vitro Ultrasound Influence on Cutaneous Permeation of Hyaluronidase

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)