Infecção natural de flebotomíneos em foco enzoótico de leishmaniose tegumentar no Estado de São Paulo, Brasil

Natural infections of Phlebotominae sandflies Pintomyia pessoai and Psychocopygus intermedius in a sylvatic enzootic focus of cutaneous leishmaniasis in S. Paulo State, Brazil, are reported. For both species confirmation was obtained by experimental inoculation in hamsters.Relata-se o encontro de infecções naturais de Pintomyia pessoai e Psychodopygus intermedius em foco enzoótico de leishmaniose tegumentar no Estado de São Paulo, Brasil. A natureza leishmaniótica desses encontros obteve confirmação através da inoculação experimental em hamsters

Aspectos ecológicos da tripanossomíase americana: XIX - desenvolvimento da domiciliação triatomínea regional, em centro de endemismo de Panstrongylus megistus

The results of observations made on triatominae bug domiciliation, after house cleaning using chemicals are reported. The work was carried out in a region beloging to the Tropical Atlantic System of Eastern Brazil considered to be as the dispersal center of the Panstrongyius megistus. The observations were made during the period March 1976 to October 1978, in areas where the original bug domiciliation found before house treatment, was composed by Triatoma infestans and Panstrongylus megistus populations. After desinsectization, surveillance research and the final survey showed the development of a new but reduced and slower domiciliation process, restricted to peridomiciliary dwellings and to the P.megistus species. The dwelling infection rates were well below those initially found. After house cleaning, these values varied from 0.8 to 2.7%, as compared with 23.4% in the initial survey. This situation continued for at least two years and four months, suggesting strongly that the surveillance activities and the selective desinsectization procedure, if necessary, should be started towards the end of the third year after the general house cleaning. It is suggested that in the meantime efforts should be made to induce the local human population to co-operate in reporting new intradomiciliary triatominae foci. Participation of domiciliated or semidomiciliated vertebrates in the transferation mechanisms of trypanosomiasis infection to the home was shown to exist. These were mainly rats (Rattus) and opossums (Didelphis), of ubiquitous behaviour. In this new domiciliation process, the role of P. megistus was practically exclusive, and the appearance of Rhodnius neglectus only sporadic. The failure of T. infestans to reappear must have been due to the low mobility of the local human population. The results of the participation of P. megistus in the reinfestation showed that this latter rapidly reach the level observed for this species in the testimony area, but with no tendency to further increase.São apresentados os resultados obtidos mediante as observações sobre o processo de domiciliação triatomínea em região incluída no domínio paisagístico Tropical Atlântico, considerado como centro de dispersão do Panstrongylus megistus. As observações foram levadas a efeito no período de março de 1976 a outubro de 1978, em áreas onde a domiciliação inicial implicou a participação dessa espécie e do Triatoma infestans. Após a realização do expurgo, as pesquisas de vigilância com ritmo trimestral e o levantamento final evidenciaram a ocorrência de novo processo de domiciliação triatomínea, porém restrita ao P. megistus e limitada ao peridomicílio, com coeficientes de positividade de edifícios acentuadamente inferiores aos registrados quando do levantamento inicial. Tal situação perdurou durante todo o período de observação. Após o expurgo, o valor geral do coeficiente de positividade dos edifícios variou do valor mínimo de 0,8% ao máximo de 2,7%, enquanto que foi de 23,4% o observado por ocasião do primeiro levantamento. Essa situação persistiu pelo tempo mínimo de dois anos e quatro meses, o que permite recomendar que a vigilância e a aplicação do expurgo seletivo, se necessário, sejam iniciadas após cerca de três anos decorridos da desinsetização geral. Recomenda-se que, nesse interim, se proceda à motivação dos habitantes locais objetivando obter-lhes a colaboração para a denúncia de novos focos intradomiciliares. No possível mecanismo de transferência da infecção tripanossômica para o ambiente domiciliar, as evidências sugerem a participação de vertebrados domiciliados, em especial modo ratos (Rattus) e gambás (Didelphis), de hábitos ubiquistas. O papel do P. megistus no processo de evolução da nova domiciliação triatomínea foi praticamente exclusivo, tendo o Rhodnius neglectus ocorrido de maneira esporádica. O não reaparecimento do T. infestans pôde ser atribuído à pouca ou mesmo ausente mobilidade da população humana local. Os resultados da participação de P. megistus na reinfestação domiciliar mostrou que esta rapidamente atingiu os níveis de positividade observados para essa espécie na área testemunha, mas sem tendência ao incremento posterior

Design of Antibacterial Agents:Alkyl Dihydroxybenzoates against Xanthomonas citri subsp. citri

Xanthomonas citri subsp. citri (Xcc) causes citrus canker, affecting sweet orange-producing areas around the world. The current chemical treatment available for this disease is based on cupric compounds. For this reason, the objective of this study was to design antibacterial agents. In order to do this, we analyzed the anti-Xcc activity of 36 alkyl dihydroxybenzoates and we found 14 active compounds. Among them, three esters with the lowest minimum inhibitory concentration values were selected; compounds 4 (52 μM), 16 (80 μM) and 28 (88 μM). Our study demonstrated that alkyl dihydroxybenzoates cause a delay in the exponential phase. The permeability capacity of alkyl dihydroxybenzoates in a quarter of MIC was compared to nisin (positive control). Compound 28 was the most effective (93.8), compared to compound 16 (41.3) and compound 4 (13.9) by percentage values. Finally, all three compounds showed inhibition of FtsZ GTPase activity, and promoted changes in protofilaments, leading to depolymerization, which prevents bacterial cell division. In conclusion, heptyl dihydroxybenzoates (compounds 4, 16 and 28) are promising anti-Xcc agents which may serve as an alternative for the control of citrus canker

Evaluation of an Antimicrobial L-Amino Acid Oxidase and Peptide Derivatives from Bothropoides mattogrosensis Pitviper Venom

Healthcare-associated infections (HAIs) are causes of mortality and morbidity worldwide. The prevalence of bacterial resistance to common antibiotics has increased in recent years, highlighting the need to develop novel alternatives for controlling these pathogens. Pitviper venoms are composed of a multifaceted mixture of peptides, proteins and inorganic components. L-amino oxidase (LAO) is a multifunctional enzyme that is able to develop different activities including antibacterial activity. In this study a novel LAO from Bothrops mattogrosensis (BmLAO) was isolated and biochemically characterized. Partial enzyme sequence showed full identity to Bothrops pauloensis LAO. Moreover, LAO here isolated showed remarkable antibacterial activity against Gram-positive and -negative bacteria, clearly suggesting a secondary protective function. Otherwise, no cytotoxic activities against macrophages and erythrocytes were observed. Finally, some LAO fragments (BmLAO-f1, BmLAO-f2 and BmLAO-f3) were synthesized and further evaluated, also showing enhanced antimicrobial activity. Peptide fragments, which are the key residues involved in antimicrobial activity, were also structurally studied by using theoretical models. The fragments reported here may be promising candidates in the rational design of new antibiotics that could be used to control resistant microorganisms

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

A reatividade negativa oriunda da poliquimioterapia imposta na Hanseníase

Introdução: A hanseníase é uma doença infectocontagiosa, que devido às repercussões clínicas e aos dados epidemiológicos é considerada de notificação compulsória. Contudo, esse transtorno quando é precocemente identificado e adequadamente manejado, evita consideravelmente o círculo vicioso de contágio e as manifestações clínicas que tornam a doença tão alvo de estigma. Objetivo: Descrever a reação negativa oriunda da poliquimioterapia imposta na hanseníase. Metodologia: Trata-se de uma revisão narrativa de literatura, fundamentada nas plataformas do Scielo, Pubmed, Lilacs e demais literaturas pertinentes ao tema, utilizando-se os seguintes descritores: Reação Hansênica, Efeitos Adversos e Poliquimioterapia, no período de janeiro de 2023. Resultados e Discussão:  Atualmente, o protocolo terapêutico voltado para a Hanseníase é a poliquimioterapia e possui boa eficácia e tolerância pela maioria dos pacientes.  No advém, a minoria destes apresenta reações adversas que variam de leve a exacerbadas e que devem ser devidamente classificados e orientados para outras opções farmacológica, objetivando impedir que o paciente abandone o tratamento, junto às enormes repercussões oriundas deste, e propiciar melhor qualidade de vida. Conclusão: Estima-se que o tratamento da Hanseníase é algo importante e indispensável para evitar problemas de saúde pública, mas este se baseia em uma alta carga associada de remédios potentes, a qual alguns portadores possuem sensibilidade e se orientados, podem continuar o tratamento até o alcance da cura.&nbsp

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost