In vitro effects of lapachol and β-lapachone against Leishmania amazonensis

Leishmaniasis is a neglected disease that affects millions of people worldwide, and special attention should be given to treatment because the available drugs have limitations, which can lead to low therapeutic adherence and parasitic resistance. This study evaluated the activity of the bioactive naphthoquinones, lapachol and β-lapachone, against Leishmania amazonensis. The cell alterations were evaluated in vitro on promastigote and amastigote forms. The lethal dose (LD50) at 24, 48, and 72 h on the promastigote's forms using lapachol was 75.60, 72.82, and 58.85 μg/mL and for β-lapachone was 0.65, 1.24, and 0.71 μg/mL, respectively. The naphthoquinones significantly inhibited the survival rate of L. amazonensis amastigotes at 83.11, 57.59, and 34.95% for lapachol (82.28, 41.14, and 20.57 µg/mL), and 78.49, 83.25, and 80.22% for β-lapachone (3.26, 1.63, and 0.815 µg/mL). The compounds on the promastigote's forms led to the loss of mitochondrial membrane potential, induced changes in the integrity of the membrane, caused damage to cells suggestive of the apoptotic process, and showed inhibition of tumor necrosis factor (TNF)-α and interleukin (IL)-6 production. The results showed that these naphthoquinones are promising candidates for research on new drugs with anti-Leishmania activity derived from natural products.

Larval trematodes hosted by Biomphalaria straminea in the Brazilian semiarid region: implications for schistosomiasis control

@#The present study aimed to identify larval trematodes shed by snails found in water bodies used by urban communities in a former schistosomiasis endemic area in the state of Piauí, in the Brazilian semiarid region. A malacological survey was performed followed by analysis of the cercariae shed by the snails after light exposure. Biomphalaria straminea specimens (n=1,224) were obtained from all seven collection sites. Cercariae shed by snails were i) single tailed, in which one type of cercariae was identified (Echinostoma cercariae), and ii) with bifurcated tail (brevifurcate apharyngeate distome, brevifurcate pharyngeate distome, and longifurcate pharyngeate distome [strigeocercaria]). Brevifurcate apharyngeate distome were further examined and the presence of spikes in swimming membranes enabled the identification of Spirorchiidae cercariae in all individuals, demonstrating the absence of cercariae compatible with Schistosoma mansoni. Nevertheless, the accurate diagnosis of S. mansoni circulation in former endemic areas is still necessary.

Avaliação histomorfométrica do efeito do extrato aquoso de urucum (norbixina) no processo de cicatrização de feridas cutâneas em ratos / Histomorphometric evaluation of the effects of the aqueous extract of annatto (norbixin) on wound skin healing in rats

A norbixina é um carotenóide dicarboxílico hidrofílico presente no pericarpo das sementes do urucuzeiro (Bixa orellana L.). O urucum é comumente utilizado na indústria alimentícia e cosmética como corante natural. O objetivo deste trabalho foi avaliar o processo de reparo cicatricial de feridas cutâneas abertas de ratos tratadas com extrato aquoso de urucum contendo 2,5% de norbixina através de análise histomorfométrica. Para tanto, realizou-se feridas cutâneas no dorso de 32 ratos Wistar machos. Estas foram tratadas com extrato de urucum (grupo experimental, n = 16) e solução salina 0,9% (grupo controle, n = 16). Aos 3, 7, 14 e 21 dias após realização do procedimento cirúrgico, os animais foram sacrificados. Os preparados histológicos obtidos foram submetidos à técnica de coloração pela Hematoxilina-Eosina (H.E.) para contagem de células inflamatórias e de fibroblastos; corados pelo azul de toluidina 1% para contagem dos mastócitos e com picrossirius-red para avaliação das fibras colágenas totais. As imagens histológicas destas lâminas foram capturadas por câmera digital acoplada ao microscópio óptico, sob foco fixo e clareza de campo, obtendo-se 10 campos por lâmina com aumento final de 400X. As fotomicrografias foram avaliadas através do software ImageJ. Os resultados obtidos foram submetidos ao teste t de student sendo o valor de p considerado significativo para p< 0,05. O tratamento tópico com extrato de urucum utilizado aumentou o infiltrado inflamatório durante o 3º, 14º e 21º dia pós-operatório. O grupo tratado apresentou maior densidade vascular quando comparado ao controle a partir do 7º e menor quantidade de fibroblastos até o 14º dia pós-cirúrgico. Conclui-se que o extrato de urucum contendo 2,5% de norbixina não é inócuo aos tecidos cutâneos e possui efeitos pró-inflamatórios e pró-angiogênicos durante o processo de reparo tecidual cutâneo em ratos, interferindo no processo fisiológico de cicatrização.

Norbixin is a dicarboxylic water-soluble carotenoid present in the pericarp of the achiote (Bixa orellana L.) seed. Annatto is commonly used by the food and cosmetic industries as a natural pigment. The aim of this study was to evaluate the healing process of open dermal wounds of rats treated with an aqueous solution of annatto containing 2.5% of norbixin carried out by histomorphometric analysis. For this end, cutaneous wounds were made on the back of 32 male Wistar rats. The wounds were treated with annatto solution (experimental group, n = 16) and saline solution 0.9% (control group, n = 16). At 3, 7, 14 and 21 days after the surgical procedure, the animals were sacrificed. After histological preparation, the histological material was submitted to the staining technique with hematoxylin-eosin for the counting of inflammatory cells and fibroblasts, with toluidine blue 1% for mast cell counting and with picrosirius red for the total collagen fibers. The images of those histological slides were captured by a digital camera connected to an optical microscope, with fixed focal length and clear field; 10 fields were captured from each slide with final zoom of 400X. The photomicrographs were analyzed by the ImageJ software. The results were submitted to the Student's t-test and the value of p < 0.05 was considered as relevant. The topical treatment with the annatto solution increased the inflammatory infiltrate during the 3rd, 14th and 21st days after surgery. The experimental group presented increased vascular density compared to the control group after the 7th day and a smaller amount of fibroblasts up to the 14th day after surgery. We concluded that the annatto solution containing 2.5% of norbixin is not innocuous to skin tissues and has proinflammatory and proangiogenic effects during the process of skin wound healing in rats, interfering in the physiological healing process.

Influência do estresse nos níveis sangüíneos de lipídios, de ácido ascórbico, de zinco e de outros parâmetros bioquímicos / Stress' influence on blood levels of lipid, ascorbic acid, zinc and other biochemical parameters

Muitos estudos apontam quanto à possibilidade de que o estresse afete a concentração de lipídeos, de ácido ascórbico, de zinco e de outros parâmetros bioquímicos e que estes elementos devem provocar alterações hormonais e bioquímicas, prejudicando o sistema cardiovascular. Assim, esta pesquisa teve como objetivo verificar o estresse em suas diferentes modalidades: tolerância, tensão, fontes, estado e vulnerabilidade e depois correlacionar as respostas de tais questionários com as alterações bioquímicas propostas em análise. A população examinada foi de 29 pacientes trabalhadores ou estudantes da Universidade federal de Santa Catarina - Brasil. Observou-se que a maioria das pessoas, da comunidade universitária analisada, convive com problemas de estresse e que os indivíduos mais tolerantes ao estresse são os menos vulneráveis. Da mesma forma, foi possível observar que os indivíduos mais tensos foram aqueles com estado de sofrimento ou sofrimento severo. Para correlação das análises bioquímicas o questionário sobre estado de estresse foi o que mais apresentou alterações significativas com os diversos parâmetros bioquímicos analisados. Nesta pesquisa pode-se notar que os problemas de estresse provocam um aumento de colesterol total e LDL-colesterol e uma pequena diminuição da fração HDL-colesterol, cálcio, magnésio, ácido ascórbico e zinco. Contudo, em nenhum dos questionários utilizados observou-se qualquer correlação entre os problemas de estresse e as análises bioquímicas como o fósforo, sódio, potássio e vitamina B12. Conclui-se que os parâmetros bioquímicos são ferramentas importantes na análise do estresse e que este deve acelerar o curso da aterosclerose coronariana.

Primeira evidência de Trypanosoma rangeli no sudeste do Brasil, região endêmica para doença de Chagas / First evidence of Trypanosoma rangeli in the southeast of Brazil, an endemic region for Chagas' disease

Informa-se, pela primeira vez, os achados de Trypanosoma rangeli no Triângulo Mineiro, Sudeste do Brasil, área altamente endêmica para doença de Chagas, assim como a infecção natural da espécie Didelphis albiventris.com este mesmo tripanosoma. Estes foram demonstrados por esfregaços sangüíneos, xenodiagnóstico, hemocultura, microhematócrito e PCR. A PCR foi realizada nas fezes e hemolinfa de Triatoma infestans, usando como controle cepas de T. rangeli provenientes da Colômbia.

This short communication informs the discovery of Trypanosoma rangeli for the first time at Triângulo Mineiro region, South-east of Brazil, a highly endemic area of Chagas' disease and also the natural infection of Didelphis albiventris with the same trypanosome. Both the findings were demonstrated through blood smears, xenodiagnosis, microhematocrit technics and PCR. The last one was realized in faeces and hemolymph of Triatoma infestans utilizing as controls strains of T. rangeli from Colombia.

Plasma clearance and biodistribution of oxidatively modified 99mTc-Beta-VLDL in rabbits

The biodistribution and removal from plasma (measured as fractional clerance rate, FCR, per hour) of native and oxidatively modified (99m)technetium-labeled Beta-very low density lipoprotein ((99m)Tc-Beta-VLDL)) were investigated in hypercholesterolemic (HC) and control (C) three-month old New Zealand rabbits. The intracellular accumulation of Beta-VLDL labeled with (99m)Tc was studied in vitro in THP-1 cells and monocyte-derived macrophages isolated from rabbits. After intravenous injection into C rabbits, copper-oxidized Beta-VLDL ((99m)Tc-ox-Beta-VLDL)) was cleared from the circulation faster (0.362 + 0.070/h) than native Beta-VLDL ((99m)Tc-nat-Beta-VLDL, 0.241 + 0.070/h)). In contrast, the FCR of (99m)Tc-ox-Beta-VLDL in HC rabbits was lower (0.100 + 0.048/h) than that of (99m)Tc-nat-Beta-VLDL (0.163 + 0.043/h). The hepatic uptake of radiolabeled lipoproteins was lower in HC rabbits (0.114 + 0.071 percent injected dose/g tissue for (99m)Tc-nat-Beta-VLDL and 0.116 + 0.057 percent injected dose/g tissue for (99m) Tc-ox-Beta-VLDL) than in C rabbits (0.301 + 0.113 percent injected dose/g tissue for (99m)Tc-nat-Beta-VLDL and 0.305 + 0.149 percent injected dose/g tissue for ((99m)Tc-ox-Beta-VLDL). The uptake of (99m)Tc-nat-Beta-VLDL and (99m)Tc-ox-Beta-VLDL by atherosclerotic aorta lesions isolated from HC rabbits ((99m)Tc-nat-Beta-VLDL:0.033 + 0.012 percent injected dose/g tissue and (99m)Tc-ox-Beta-VLDL: 0.039 + 0.017 percent injected dose/g tissue) was higher in comparison to that of non-atherosclerotic aortas from C rabbits (99m)Tc-nat-Beta-VLDL: 0.023 + 0.010 percent injected dose/g tissue and (99m)Tc-ox-Beta VLDL: 0.019 + 0.010 percent injected dose/g tissue). However, (99m) Tc-nat-Beta-VLDL and (99m)Tc-ox-Beta-VLDL were taken up by atherosclerotic lesions at similar rates. In vitro studies showed that both monocyte-derived macrophages isolated from rabbits and THP-1 macrophages significantly internalized more (99m)Tc-ox-Beta-VLDL than (99m)Tc-nat-Beta-VLDL. These results indicate that in cholesterol-fed rabbits (99m)Tc-ox-Beta-VLDL is slowly cleared from plasma and accumulates in atherosclerotic lesions. However, although the extent of in vitro uptake of (99m)Tc-ox-Beta-VLDL by macrophages was high, the in vivo accumulation of this radiolabeled lipoprotein by atherosclerotic lesions did not differ from that of (99m)Tc-nat-Beta-VLDL.

Antibody response after immunization of Brazilian children with serogroup C meningococcal polysaccharide noncovalently complexed with outer membrane proteins

We have studied the antibody response of Brazilian vaccines to C meningococcal polysaccharide (C-PS) after one or two doses of a vaccine composed of C-PS, outer membrane proteins of B meningococci and aluminum hydroxide. Total IgG, IgG1 and IgG2 as well as bactericidal activity mediated by complement were measured in serum samples from children 3 to 83 months of age (post-vaccination IgG, IgG1 and IgG2 levels of 2.4 to 13.4 µg/ml; less than 18 to 67.8 U/ml and less than 8 to 106.8U/ml, respectively) and from individuals 10 to 14 years of age (post-vaccination IgG, IgG1 and IgG2 levels of 14.6 µg/ml, 23,7 U/ml and 112.0 U/ml, respectively). The antibody response, measured as IgG levels, was age-dependent. Although high antibody levels were demonstrableby enzyme-linked immunosorbent assay (ELISA), bactericidal activity was not demonstrable (less than 1:4) in serum from children aged less than 24 months. A significant bactericidal activity was detected in serum of children older than 49 months of age and in individuals 10 to 14 years of age. A predominance of IgG2 was observed in post-vaccination serum samples from children belonging to those two age groups. The antibody concentration sufficient to confer protection as well as the possible causes of the poor correlation observed between ELISA and bactericidal activity results are discussed

Increased plasma removal of microemulsions resembling the lipid phase of low-density lipoproteins (LDL) in patients with acute myeloid leukemia: a possible new strategy for the treatment of the disease

A microemulsion of lipid composition resembling low-density lipoprotein (LDL), but devoid of apolipoproteins and labeled with [14C]-cholesteryl oleate was injected into 16 healthy subjects and into 15 patients with acute myeloid leukemia (AML). Removal from plasma of the lipid label was higher in the leukemic group compared to healthy subjects in terms of fractional clearance rate (0.185 +/- 0.205 and 0.080 +/- 0.030 h-1, respectively, P < 0.03). When the emulsion was again injected into 10 of the AML patients after complete hematological remission, the fractional clearance rate of cholesteryl ester was reduced to one third of the value observed prior to treatment (0.061 +/- 0.038 h-1) and was not different from that obtained for the healthy subjects. Also, in untreated AML patients, serum LDL-cholesterol levels inversely correlated with the values of fractional clearance rate of the microemulsion. This correlation was no longer observed after treatment. These data suggest that the LDL-like microemulsion was selectively taken up by the neoplastic cells presumably by interaction with LDL receptors. Therefore, microemulsions may function as potential carriers for anticancer drugs that are targeted to tumor cells for patients with acute myeloid leukemia. Unlike native LDL, microemulsions are suitable for utilization in routine clinical practice

Vagotomia gastrica proximal. / Proximal gastric vagotomy

O autor realizou em 127 pacientes selecionados, de abril de 1975 a marco de 1981, vagotomia gastrica proximal para tratamento cirurgico de ulceras duodenais, piloricas e de antro terminal, bem como de ulceras duodenais associadas a ulcera gastrica e como tratamento complementar em herniorrafias diafragmaticas com fundoplicatura de pacientes com graves esofagites de refluxo. A principal indicacao cirurgica foi intratabilidade clinica de ulcera peptica e os resultados podem ser considerados otimos e bons em aproximadamente 90% dos pacientes, alguns ja com seis anos de pos-operatorio. A mortalidade operatoria foi nula e o indice de complicacoes, trans e pos-operatorias, foi muito baixo. Conclui pela excelencia do metodo, observados os criterios tecnicos e de selecao dos pacientes