First molecular-based detection study of Leishmania infantum in the Tapirapé indigenous population in the Brazilian Amazon.

Species of the genus Leishmania parasitize mammals and have life cycles that alternate between vertebrate and invertebrate hosts. Most species develop in a hematophagous arthropod and infect a specific vertebrate host that may belong to diverse orders and families. Visceral leishmaniasis is a chronic zoonosis with a wide geographic distribution, affecting 350 million people globally, mostly in areas with a high risk of infection. In Brazil, this disease not only has a high incidence but is also expanding to new areas, both in urban centers and rural areas, including territories with tribal communities, due to increasing human intervention. The objective of this study was to perform cathepsin L-like gene-based molecular diagnosis of Leishmania infantum in the indigenous Tapirapé ethnic group in the state of Mato Grosso. From the 372 individuals assessed, only 0.8% (3/372) tested positive for L. infantum, all from the same village (Urubu Branco). Despite the small number of infected individuals, this study demonstrates the first human cases of Leishmania infantum infection in this population, suggesting the need for regular monitoring of visceral leishmaniasis in the area and leading to a broad discussion on the planning and implementation of public health measures for the indigenous population, while respecting their distinctive territories and culture.

First molecular-based detection study of Leishmania infantum in the Tapirapé indigenous population in the Brazilian Amazon

Species of the genus Leishmania parasitize mammals and have life cycles that alternate between vertebrate and invertebrate hosts. Most species develop in a hematophagous arthropod and infect a specific vertebrate host that may belong to diverse orders and families. Visceral leishmaniasis is a chronic zoonosis with a wide geographic distribution, affecting 350 million people globally, mostly in areas with a high risk of infection. In Brazil, this disease not only has a high incidence but is also expanding to new areas, both in urban centers and rural areas, including territories with tribal communities, due to increasing human intervention. The objective of this study was to perform cathepsin L-like gene-based molecular diagnosis of Leishmania infantum in the indigenous Tapirapé ethnic group in the state of Mato Grosso. From the 372 individuals assessed, only 0.8% (3/372) tested positive for L. infantum, all from the same village (Urubu Branco). Despite the small number of infected individuals, this study demonstrates the first human cases of Leishmania infantum infection in this population, suggesting the need for regular monitoring of visceral leishmaniasis in the area and leading to a broad discussion on the planning and implementation of public health measures for the indigenous population, while respecting their distinctive territories and culture.

Deficiency of sex hormones does not affect 17-ß-estradiol-induced coronary vasodilation in the isolated rat heart.

The relaxation of coronary arteries by estrogens in the coronary vascular beds of naive and hypertensive rats has been well described. However, little is known about this action in gonadectomized rats. We investigated the effect of 17-ß-estradiol (E2) in coronary arteries from gonadectomized rats, as well as the contributions of endothelium-derived factors and potassium channels. Eight-week-old female and male Wistar rats weighing 220-300 g were divided into sham-operated and gonadectomized groups (n=9-12 animals per group). The baseline coronary perfusion pressure (CPP) was determined, and the vasoactive effects of 10 µM E2 were assessed by bolus administration before and after endothelium denudation or by perfusion with NG-nitro-L-arginine methyl ester (L-NAME), indomethacin, clotrimazole, L-NAME plus indomethacin, L-NAME plus clotrimazole or tetraethylammonium (TEA). The CPP differed significantly between the female and sham-operated male animals. Gonadectomy reduced the CPP only in female rats. Differences in E2-induced relaxation were observed between the female and male animals, but male castration did not alter this response. For both sexes, the relaxation response to E2 was, at least partly, endothelium-dependent. The response to E2 was reduced only in the sham-operated female rats treated with L-NAME. However, in the presence of indomethacin, clotrimazole, L-NAME plus indomethacin or L-NAME plus clotrimazole, or TEA, the E2 response was significantly reduced in all groups. These results highlight the importance of prostacyclin, endothelium-derived hyperpolarizing factor, and potassium channels in the relaxation response of coronary arteries to E2 in all groups, whereas nitric oxide may have had an important role only in the sham-operated female group.

Role of NO-cGMP pathway in ovine cervical relaxation induced by Erythroxylum caatingae Plowman.

Erythroxylum caatingae Plowman has a myorelaxing effect on smooth muscle tissue. We investigated the effect of the crude ethanolic extract of E. caatingae Plowman (Ec-EtOH) on the contractility of the ovine cervix. In an isometric system, circular strips were subjected to 90mM potassium (K(+)) or 30µM carbamylcholine (CCh)-induced contraction. We then exposed the tissue to cumulative concentrations of Ec-EtOH (1-729 µg/ml). In other bath solutions, the tissues were exposed to l-NG-nitroarginine methyl ester (l-NAME; 100µM), l-NAME (100µM)+l-arginine (300µM), 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, ODQ; 5µM), 4-aminopyridine (4-AP; 3mM), tetraethylammonium (TEA; 0.3mM), glybenclamide (1µM), atosiban (10µM) or verapamil (3µM), followed by the addition of Ec-EtOH (1-729 µg/ml). We also evaluated the effect of cervical Ec-EtOH infusion (2mg) on cervical contractility in vivo. Ec-EtOH decreased cervical contractility induced by K(+) or CCh, and 729 µg/ml Ec-EtOH decreased 85.4±5.1% the amplitude of basal contractility in vitro, with an EC50 of 17.9±3.7 µg/ml. This effect of Ec-EtOH was prevented by l-NAME or ODQ. l-arginine impaired the blunting effect of l-NAME on cervical relaxation caused by Ec-EtOH. However, the potassium channel blockers 4-AP, TEA, and glybenclamide did not modify this myorelaxation triggered by Ec-EtOH. Ec-EtOH also decreased acetylcholine-induced contractions in tissue preincubated with verapamil. In addition, Ec-EtOH decreased ovine cervical contractions in vivo. Thus, Ec-EtOH had a relaxant effect on ovine cervical contractions. This may involve the nitric oxide signal, mediated by cGMP cellular transduction, and be related to intracellular calcium sequestration.

Deficiency of sex hormones does not affect 17-ß-estradiol-induced coronary vasodilation in the isolated rat heart

The relaxation of coronary arteries by estrogens in the coronary vascular beds of naive and hypertensive rats has been well described. However, little is known about this action in gonadectomized rats. We investigated the effect of 17-ß-estradiol (E2) in coronary arteries from gonadectomized rats, as well as the contributions of endothelium-derived factors and potassium channels. Eight-week-old female and male Wistar rats weighing 220-300 g were divided into sham-operated and gonadectomized groups (n=9−12 animals per group). The baseline coronary perfusion pressure (CPP) was determined, and the vasoactive effects of 10 μM E2 were assessed by bolus administration before and after endothelium denudation or by perfusion with NG-nitro-L-arginine methyl ester (L-NAME), indomethacin, clotrimazole, L-NAME plus indomethacin, L-NAME plus clotrimazole or tetraethylammonium (TEA). The CPP differed significantly between the female and sham-operated male animals. Gonadectomy reduced the CPP only in female rats. Differences in E2-induced relaxation were observed between the female and male animals, but male castration did not alter this response. For both sexes, the relaxation response to E2 was, at least partly, endothelium-dependent. The response to E2 was reduced only in the sham-operated female rats treated with L-NAME. However, in the presence of indomethacin, clotrimazole, L-NAME plus indomethacin or L-NAME plus clotrimazole, or TEA, the E2 response was significantly reduced in all groups. These results highlight the importance of prostacyclin, endothelium-derived hyperpolarizing factor, and potassium channels in the relaxation response of coronary arteries to E2 in all groups, whereas nitric oxide may have had an important role only in the sham-operated female group.

Rehydration After Water Stress in Forager Workers of Coptotermes gestroi (Wasmann) (Blattaria: Rhinotermitidae).

Water maintenance is vital for termite survival under dry conditions, hence environment humidity is one of the most important factors that controls the distribution of Isoptera. To understand the dynamics of termite rehydration after water loss, two bioassays were performed with forager workers of Coptotermes gestroi (Wasmann) submitted to water stress. Insects were weighed and placed into Petri dishes without water and food for periods of 3, 15, and 30 h. For each period of water stress, 10 replicates were performed in the treatment and control groups, totalling 120 experimental units. Forager workers lost body mass across all periods of water stress and tested with the highest reduction for the 30 h exposure period. Subsequent access to water resulted in termite rehydration, and final weight values were near to initial body mass values. These results demonstrate that workers of C. gestroi experienced large reductions of body mass under water stress, but these reductions were not severe enough to cause mortality. Additionally, termites were able to rehydrate after water stress conditions. This is a potential risk factor to be considered in cases of new infestations because C. gestroi workers will be able to cause economic damage in their new locations even when deprived of water during their transportation by humans.

Foraging in subterranean termites (Isoptera: Rhinotermitidae): how do Heterotermes tenuis and Coptotermes gestroi behave when they locate equivalent food resources?

A previous research suggests that when subterranean termites locate equivalent food they consume the initial food resource. However, little is known about the movement of foragers among these food sources. For this reason, this study analyzed the feeding behavior of Heterotermes tenuis and Coptotermes gestroi in the presence of equivalent foods. The experimental arenas were composed of a release chamber connected to food chambers. The consumption of each wood block and percentage of the foraging individuals recruited for the food chambers were observed in relation to the total survival rate. The results showed that in the multiple-choice tests, wood block consumptions and the recruitment of individuals did not differ between replicates of each termite species. However, in different tests of tenacity, the chambers with the first food presented higher feeding rates by both H. tenuis and C. gestroi and resulted in a higher recruitment of workers and soldiers. In these conditions, it may be concluded that foragers of either species do not concentrate their efforts on the consumption of only one food resource when they are able to reach multiple cellulosic sources simultaneously. Additionally, the data concerning tenacity tests suggest that there is a chronologic priority of consumption in relation to the discovery of available food sources. Knowledge about the foraging biology of subterranean termites is important for future studies of their feeding behavior, and it is indispensable for improving control strategies.

A note on the infection of Scomberomorus brasiliensis (Osteichthyes, Scombridae) by Kudoa sp. (Myxozoa: Multivalvulida).

The infection of Scomberomorus brasiliensis by the myxozoan Kudoa sp. is reported. The parasites formed plasmodiae inside the skeletal muscle fibres. The spores were quadrate in apical view and bell-like shaped in lateral view, containing four equally sized more or less rounded polar capsules. No detrimental effects were observed in the host, namely muscle liquefaction. The importance of these parasites is discussed.

Antinociceptive activity of discretamine isolated from Duguetia moricandiana.

The phytochemical study of Duguetia moricandiana Mart. (Annonaceae) yielded the isolation of the alkaloid which was identified by spectral analysis as discretamine. The evaluation of antinociceptive activity carried out by the acetic acid-induced writhing, formalin and hot plate tests in mice, suggests a potent antinociceptive effect. Discretamine (5, 10 and 20 mg kg⁻¹, i.p.) significantly reduced the number of writhes similarly at all doses tested and the number of paw licks during the first phase of formalin test when compared to control. The effect of discretamine on hot plate response provides a confirmation of its central effect. These results indicate antinociceptive properties of this alkaloid.

Ocorrência de doença infundibular, sobremordida e ganchos em equinos de cavalaria militar / Infundibular disease, over-bite, and dental hooks occurrence in military horse

Avaliou-se a ocorrência da doença infundibular (DI) e a associação entre sobremordida (SM) e ganchos dentários rostral e caudal da maxila e mandíbula. Utilizaram-se 88 equinos - 52 machos e 36 fêmeas -, entre três e 27 anos. Para os exames odontológicos, os animais foram contidos em brete e sedados com xilazina 10 por cento a 0,5mg/kg IV e utilizaram-se abridor de boca, fotóforo elétrico e sonda odontológica de aço inox. Agruparam-se os equinos por idade. O grupo 1 foi formado por animais até nove anos; o G2 de 10 a 14 e G3 de 15 a 27 anos. Foi diagnosticada DI em (37,5 por cento) animais, nos dentes molares e pré-molares. A incidência maior de DI foi nos dentes 109 (11,4 por cento) e 209 (12,5 por cento). Houve correlação positiva entre a idade e o número de dentes acometidos (r=0,26; P<0,02). A maior ocorrência de DI no grupo mais acometido (G3) foi nos dentes 108 e 208. Verificaram-se 66 por cento de SM e 65 por cento de ganchos. Observou-se correlação entre SM e presença total de ganchos (r=0,26, P=0,016), entre SM e ganchos rostrais maxilares e mandibulares (r=0,25,P=0,016) e ganchos rostrais maxilares(r=0,24, P=0,02). Animais com ganchos pré-molares maxilares tiveram 2,8 vezes mais chance de apresentarem SM (IC 95 por cento = 1,1 a 7,1).

The occurrence of infundibular disease (ID) and the association between over-bite (OB) and rostral and caudal hooks on teeth of the maxilla and jaw were evaluated in 88 horses - 52 males and 36 females - aging from between 3 and 27 years old. The horses were restrained in stocks, sedated with xylazine and examined using a mouth-speculum and a stainless steel pick. The data were recorded on individual charts. The animals were grouped by age: group 1: 3 to 9, group 2: 10 to 14, and group 3: 15 to 27 years old. ID was identified on the premolar and molar teeth in 37.5 percent of horses. There was a positive correlation between age and number of affected teeth (r=0.26, P<0.02). The most affected teeth were the 109 (11.4 percent) and 209 (12.5 percent). The highest occurrence of ID in the most affected group (G3) was on the 108 and 208 teeth. There were 66 percent of OB and 65 percent of hooks. There was a correlation between OB and the presence of total (r=0.26, P=0.016), maxillary and mandibular (r=0.25, P=0.016), and maxillary rostral hooks (r=0.24, P=0.02). Only the association between OB and maxillary rostral hooks was significant. Animals with maxillary pre-molars hooks were 2.8 times predisposed to have OB (CI 95 percent=1.1 to 7.1).

Efeito embriotóxico, teratogênico e abortivo de plantas medicinais / Embryotoxic, teratogenic and abortive effects of medicinal plants

O uso milenar de plantas medicinais mostrou ao longo dos anos, que determinadas plantas apresentam substâncias potencialmente perigosas. Do ponto de vista científico, algumas pesquisas mostraram que muitas dessas plantas possuem substâncias agressivas e por essa razão devem ser utilizadas com cuidado, respeitando seus riscos toxicológicos. Os efeitos mais preocupantes do uso indiscriminado de plantas medicinais são embriotóxico, teratogênico e abortivo, uma vez, que os constituintes da planta podem atravessar a placenta, chegar ao feto e gerar um desses efeitos. Este estudo objetiva fornecer uma listagem das principais plantas medicinais que tenham efeitos embriotóxicos, teratogênicos e abortivos comprovados, conhecendo as partes da planta utilizadas e seus respectivos nomes científicos, com a finalidade de alertar gestantes quanto aos riscos de seu uso. Realizou-se buscas nas bases eletrônicas de dados SciELO, PubMed, MEDLINE, LILACS, CAPES e Google acadêmico. Nos resultados encontrados, plantas como Arnica (Arnica montana), Artemísia (Artemisia vulgaris), Arruda (Ruta chalepensis/ Ruta graveolens), Barbatimão (Stryphnodendron polyphyllum), Boldo (Vernonia condensata) dentre outras, podem vir a gerar um desses efeitos. A partir deste estudo comprova-se que para a maioria das plantas medicinais não há dados a respeito da segurança de seu uso durante a gravidez.

The ancient use of medicinal plants has shown over the years that certain plants have potentially dangerous substances. From a scientific point of view, some studies have shown that many of these plants contain aggressive substances and therefore should be used with caution, respecting their toxicological risks. The most important effects of the indiscriminate use of medicinal plants are embryotoxic, teratogenic and abortifacient since the plant constituents can cross the placenta, reaching the fetus and leading to one of these effects. This study aimed to provide a list of the major medicinal plants that have proven embryotoxic, teratogenic and abortifacient effects, including the used plant parts and their respective scientific names, in order to warn pregnant women about the risks of its use. Searches were carried out in the electronic databases SciELO, PubMed, MEDLINE, LILACS, CAPES and Google Scholar. Results indicated that plants such as mountain arnica (Arnica montana), mugwort (Artemisia vulgaris), fringed rue (Ruta chalepensis / Ruta graveolens), "Barbatimão" (Stryphnodendron polyphyllum) and "Boldo" (Vernonia condensata) are likely to generate such an effect. This study shows that for most medicinal plants there are not data regarding the safety of their use during pregnancy.

Antinociceptive effect of citronellal in mice.

Citronellal is a monoterpene reported to be a major component of the essential oils in various aromatic species of plants. The present study evaluated the central nervous system depressant and antinociceptive properties of citronellal through behavioral experimental models. Following intraperitoneal injection, citronellal induced the reduction of spontaneous activity, ataxia, analgesia, and sedation. In pentobarbital-induced hypnosis, CTL (citronellal) at 50, 100, and 200 mg/kg (i.p.) significantly increased sleeping time (88.0 +/- 11.4, 100.2 +/- 16.4, and 119.5 +/- 20.9 min) when compared to vehicle solution injections (43.0 +/- 6.1). Citronellal (100 and 200 mg/kg, i.p.) significantly reduced the number of writhes (66.4 and 81.9%) in a writhing test and the number of paw licks during phase 1 (47.0 and 66.8%) and phase 2 (71.1 and 79.2%) of a formalin test when compared to control group animals. In addition, the results of a hot plate test showed central analgesic properties for citronellal (p < 0.05). These results indicate depressant, hypnotic, and antinociceptive properties of this monoterpene.

Ovarian development and spawning of Serra Spanish mackerel in coastal waters of Northeastern Brazil.

The Serra Spanish mackerel, Scomberomorus brasiliensis is an important fishery resource of the Atlantic Ocean and is a major component of artisanal fisheries in northern and northeastern Brazil. Ovarian development and spawning period of S. brasiliensis were investigated using both macroscopic and histological techniques. Mean monthly values of GSI and ovarian maturation indicate that the main spawning period occurs during the rainy season.