Evaluation of Thiazolidine Derivatives with Potential Anti-ZIKV Activity.

OBJECTIVE: In this study, we have synthesized 19 Thiazolidine (TZD) derivatives to investigate their potential anti-ZIKV effects. METHODS: Nineteen thiazolidine derivatives were synthesized and evaluated for their cytotoxicity and antiviral activity against the ZIKA virus. RESULTS: Among them, six demonstrated remarkable selectivity against the ZIKV virus, exhibiting IC50 values of <5µM, and the other compounds did not demonstrate selectivity for the virus. Interestingly, several derivatives effectively suppressed the replication of ZIKV RNA copies, with derivatives significantly reducing ZIKV mRNA levels at 24 hours post-infection (hpi). Notably, two derivatives (ZKC-4 and -9) stood out by demonstrating a protective effect against ZIKV cell entry. Informed by computational analysis of binding affinity and intermolecular interactions within the NS5 domain's N-7 and O'2 positions, ZKC-4 and FT-39 displayed the highest predicted affinities. Intriguingly, ZKC-4 and ZKC-9 derivatives exhibited the most favorable predicted binding affinities for the ZIKV-E binding site. CONCLUSION: The significance of TZDs as potent antiviral agents is underscored by these findings, suggesting that exploring TZD derivatives holds promise for advancing antiviral therapeutic strategies.

Trypanosoma cruzi killing and immune response boosting by novel phenoxyhydrazine-thiazole against Chagas disease.

Trypanosoma cruzi (T. cruzi) causes Chagas, which is a neglected tropical disease (NTD). WHO estimates that 6 to 7 million people are infected worldwide. Current treatment is done with benznidazole (BZN), which is very toxic and effective only in the acute phase of the disease. In this work, we designed, synthesized, and characterized thirteen new phenoxyhydrazine-thiazole compounds and applied molecular docking and in vitro methods to investigate cell cytotoxicity, trypanocide activity, nitric oxide (NO) production, cell death, and immunomodulation. We observed a higher predicted affinity of the compounds for the squalene synthase and 14-alpha demethylase enzymes of T. cruzi. Moreover, the compounds displayed a higher predicted affinity for human TLR2 and TLR4, were mildly toxic in vitro for most mammalian cell types tested, and LIZ531 (IC50 2.8 µM) was highly toxic for epimastigotes, LIZ311 (IC50 8.6 µM) for trypomastigotes, and LIZ331 (IC50 1.9 µM) for amastigotes. We observed that LIZ311 (IC50 2.5 µM), LIZ431 (IC50 4.1 µM) and LIZ531 (IC50 5 µM) induced 200 µg/mL of NO and JM14 induced NO production in three different concentrations tested. The compound LIZ331 induced the production of TNF and IL-6. LIZ311 induced the secretion of TNF, IFNγ, IL-2, IL-4, IL-10, and IL-17, cell death by apoptosis, decreased acidic compartment formation, and induced changes in the mitochondrial membrane potential. Taken together, LIZ311 is a promising anti-T. cruzi compound is not toxic to mammalian cells and has increased antiparasitic activity and immunomodulatory properties.

In vitro bioevaluation and docking study of dihydrosphingosine and ethambutol analogues against sensitive and multi-drug resistant Mycobacterium tuberculosis.

Tuberculosis remains a major public health problem and one of the top ten causes of death worldwide. The alarming increase in multidrug-resistant and extensively resistant variants (MDR, pre-XDR, and XDR) makes the disease more difficult to treat and control. New drugs that act against MDR/XDR strains are needed for programs to contain this major epidemic. The present study aimed to evaluate new compounds related to dihydro-sphingosine and ethambutol against sensitive and pre-XDR Mycobacterium strains, as well as to characterize the pharmacological activity through in vitro and in silico approaches in mmpL3 protein. Of the 48 compounds analyzed, 11 demonstrated good to moderate activity on sensitive and MDR Mycobacterium tuberculosis (Mtb), with a Minimum Inhibitory Concentration (MIC) ranging from 1.5 to 8 µM. They presented 2 to 14 times greater potency of activity when compared to ethambutol in pre-XDR strain, and demonstrated a selectivity index varying between 2.21 and 82.17. The substance 12b when combined with rifampicin, showed a synergistic effect (FICI = 0.5) on sensitive and MDR Mtb. It has also been shown to have a concentration-dependent intracellular bactericidal effect, and a time-dependent bactericidal effect in M. smegmatis and pre-XDR M. tuberculosis. The binding mode of the compounds in its cavity was identified through molecular docking and using a predicted structural model of mmpL3. Finally, we observed by transmission electron microscopy the induction of damage to the cell wall integrity of M. tuberculosis treated with the substance 12b. With these findings, we demonstrate the potential of a 2-aminoalkanol derivative to be a prototype substance and candidate for further optimization of molecular structure and anti-tubercular activity in preclinical studies.

1,3-Thiazole derivatives as privileged structures for anti-Trypanosoma cruzi activity: Rational design, synthesis, in silico and in vitro studies.

Chagas disease is a deadly and centenary neglected disease that is recently surging as a potential global threat. Approximately 30% of infected individuals develop chronic Chagas cardiomyopathy and current treatment with the reference benznidazole (BZN) is ineffective for this stage. We presently report the structural planning, synthesis, characterization, molecular docking prediction, cytotoxicity, in vitro bioactivity and mechanistic studies on the anti-T. cruzi activity of a series of 16 novel 1,3-thiazoles (2-17) derived from thiosemicarbazones (1a, 1b) in a two-step and reproducible Hantzsch-based synthesis approach. The anti-T. cruzi activity was evaluated in vitro against the epimastigote, amastigote and trypomastigote forms of the parasite. In the bioactivity assays, all thiazoles were more potent than BZN against epimastigotes. We found that the compounds presented an overall increased anti-tripomastigote selectivity (Cpd 8 was 24-fold more selective) than BZN, and they mostly presented anti-amastigote activity at very low doses (from 3.65 µM, cpd 15). Mechanistic studies on cell death suggested that the series of 1,3-thiazole compounds herein reported cause parasite cell death through apoptosis, but without compromising the mitochondrial membrane potential. In silico prediction of physicochemical properties and pharmacokinetic parameters showed promising drug-like results, being all the reported compounds in compliance with Lipinski and Veber rules. In summary, our work contributes towards a more rational design of potent and selective antitripanosomal drugs, using affordable methodology to yield industrially viable drug candidates.

NPCdc, a synthetic natriuretic peptide, is a substrate to neprilysin and enhances blood pressure-lowering induced by enalapril in 5/6 nephrectomized rats.

NPCdc is a natriuretic peptide synthesized from the amino acid sequence of the Crotalus durissus cascavella snake venom peptide, NP2Casca. NPCdc presents hypotensive and antioxidants effects. This study aimed to investigate in vivo whether angiotensin I-converting enzyme (ACE) inhibition would influence the impact of NPCdc in arterial pressure of rats submitted to 5/6 nephrectomy (Nx). Adult male Wistar rats following a 5/6 Nx were treated with enalapril (NxE group, 10 mg/kg/day, n = 9) or vehicle (Nx group, n = 8) for two weeks. On the 15th day after Nx, rats were anaesthetized and submitted to mean arterial pressure (MAP) determination before and after receiving two intravenous injections of saline (vehicle, n = 9) or NPCdc (0.3 µg/kg dissolved in saline, n = 18) separated by a 20-min interval. The kidneys were submitted to oxidative stress analysis. The basal MAP of the NxE group was nearly 20% lower (P < 0.05) than non-treated rats. NPCdc administration decreased the MAP in both groups; however, in the NxE group, the effects were observed only in the second injection. The peptide also decreased the NADPH oxidase activity in the renal cortex. Additionally, the hydrolysis of NPCdc by recombinant neprilysin (NEP) was monitored by mass spectrometry. NPCdc was cleaved by NEP at different peptides with an inhibition constant (Ki) of 1.5 µM, determined by a competitive assay using the NEP fluorescence resonance energy transfer (FRET) peptide substrate Abz-(d)Arg-Gly-Leu-EDDnp. Docking experiments confirmed the high affinity of NPCdc toward NEP. These findings provide new insights into the antihypertensive and antioxidant mechanism of action of NPCdc. Altogether, the results presented here suggest that NPCdc must be further studied as a potential therapy for cardiorenal syndromes.

Streptomyces hygroscopicus UFPEDA 3370: A valuable source of the potent cytotoxic agent nigericin and its evaluation against human colorectal cancer cells.

Streptomyces hygroscopicus UFPEDA 3370 was fermented in submerged cultivation and the biomass extract was partitioned, obtaining a fraction purified named EB1. After purification of EB1 fraction, nigericin free acid was obtained and identified. Nigericin presented cytotoxic activity against several cancer cell lines, being most active against HL-60 (human leukemia) and HCT-116 (human colon carcinoma) cell lines, presenting IC50 and (IS) values: 0.0014 µM, (30.0) and 0.0138 µM (3.0), respectively. On HCT-116, nigericin caused apoptosis and autophagy. In this study, nigericin was also screened both in vitro and in silico against a panel of cancer-related kinases. Nigericin was able to inhibit both JAK3 and GSK-3ß kinases in vitro and its binding affinities were mapped through the intermolecular interactions with each target in silico.

Efeitos da auriculoterapia na amamentação: uma revisão integrativa / Effects of auriculotherapy on breastfeeding: an integrative review

Introdução: A prática de aleitamento materno é de grande importância para o desenvolvimento e crescimento da criança tanto físico quanto psicológico, propiciar a interação entre mãe e filho, além de reduzir estresse, mau humor, etc. A auriculoterapia, no Brasil, está incluída na PNPIC E compreende a estimulação mecânica de pontos e regiões específicas espalhados pelo pavilhão auricular. Este estudo teve como objetivo resumir e analisar as evidências de pesquisas clínicas sobre a utilização da auriculoterapia no estimulo a amamentação. Métodos: Trata-se de uma revisão integrativa que foi realizada no período de fevereiro de 2021 a outubro de 2021. Foi realizada uma busca de literatura, utilizando a estratégia PICo, sendo P (População): mulheres com dificuldade de lactação, I (Fenômeno de interesse): Auriculoterapia, Co (Contexto): Não se aplica, As bases de dados escolhidas para a busca de literatura foram Science Direct, BVS (MedLine, LILACS, SciELO) e Google Acadêmico. A análise bibliográfica incluiu todos os estudos clínicos utilizando o auriculoterapia e amamentação, restritos aos idiomas inglês, espanhol e português. Foram utilizados os descritores "Auriculoterapia"; "Acupuntura", "orelha"; "Amamentação"; "Leite materno"; "Lactação". Resultados: A busca resultou em 215 publicações, das quais 21 foram removidas, após a triagem, por registros duplicados. Foram avaliados os textos completos dos estudos restantes. Um total de 3 artigos preencheram os critérios de inclusão. Os desfechos principais encontrados foram o aumento da produção de leite, o aumento da permanência da lactação materna e relaxamento. Discussão: Todos os estudos incluídos demonstraram os efeitos positivos da aplicação da auriculoterapia no estímulo à amamentação. Conclusão: Mesmo que os estudos abordados sugiram que a auriculoterapia tem efeitos positivos na amamentação, essa revisão não é suficiente para comprovar a eficácia da técnica, principalmente pela quantidade de estudos investigados e qualidade dos mesmos.

Introduction: The practice of breastfeeding is of great importance for the development and growth of the child, both physical and psychological, provide interaction between mother and child, in addition to reducing stress, bad mood, etc. A auriculotherapy, in Brazil, is included in the PNPIC and includes stimulation mechanics of specific points and regions spread across the ear. This one study aimed to summarize and analyze clinical research evidence on the use of auriculotherapy to encourage breastfeeding. Methods: This is of an integrative review that was carried out from February 2021 to October 2021. A literature search was carried out, using the PICo strategy, with P (Population): women with lactation difficulties, I (Phenomenon of interest): Auriculoterapia, Co (Context): Not applicable, The databases chosen for the literature search were Science Direct, VHL (MedLine, LILACS, SciELO) and Google Academic. The bibliographic analysis included all clinical studies using the auriculotherapy and breastfeeding, restricted to English, Spanish and Portuguese. The descriptors "Auriculotherapy" were used; "Acupuncture", "ear"; "Breast-feeding"; "Breast milk"; "Lactation". Results: The search resulted in 215 publications, of which 21 were removed, after screening, due to duplicate records. The full texts of the remaining studies were evaluated. A total of 3 articles met the inclusion criteria. The main outcomes found were the increased milk production, increased duration of maternal lactation and relaxation. Discussion: All included studies demonstrated the effects positive aspects of applying auriculotherapy to encourage breastfeeding. Conclusion: Even though the studies discussed suggest that auriculotherapy has positive effects in breastfeeding, this review is not sufficient to prove the effectiveness of the technique, mainly due to the quantity of studies investigated and their quality.

Healthcare system capacity of the municipalities in the State of Rio de Janeiro: infrastructure to confront COVID-19 / Capacidad del sistema de salud en los municipios del estado de Río de Janeiro: infraestructura para enfrentar la COVID-19 / Capacidade do sistema de saúde nos municípios do Rio de Janeiro: infraestrutura para enfrentar a COVID-19

Abstract Considering the growing number of cases requiring emergency care as a result of SARS-CoV-2 in the Brazilian State of Rio de Janeiro, this study focuses on mapping the health infrastructure of the municipalities of the state, comparing the Structure Efficiency Index (IEE) before (2016) and after the COVID-19 pandemic. The article fills a gap in the academic literature, informing public health policies specialists and technicians, as well as policy and decision-makers, about the capacity of municipalities to face the problem. We calculated the Structure Efficiency Index (IEE) of the states' 92 municipalities and positioned them on the pandemic curve. It was possible to verify that the government of the State of Rio de Janeiro needs to start acting to suppress COVID-19, maintaining the policy of providing more hospital beds, and purchasing equipment. However, it is also necessary to consider the particularities and deficiencies of each region, as the policy to transfer patients to places with available beds can contribute to the spread of the disease.

Resumen Considerando el número creciente de casos de atención de emergencia procedentes del SARS-CoV-2, en el estado de Río de Janeiro, este estudio se centra en el mapeo de la infraestructura de salud en los municipios de dicho estado, con el fin de informar a los especialistas, técnicos, formuladores y tomadores de decisiones de políticas de salud pública sobre la capacidad de cada localidad para enfrentar el problema. Para esto, calculamos el índice de eficiencia de estructura (IEE) colocando los 92 municipios del estado en la curva de la pandemia. Se pudo verificar que el Gobierno del Estado de Río de Janeiro debe comenzar a actuar para suprimir la COVID-19 manteniendo la política de apertura o reapertura de camas y adquisición de equipos. Sin embargo, también se deben considerar las particularidades y deficiencias de cada región, ya que la política de traslado de pacientes postrados a otras regiones con camas disponibles puede propagar la enfermedad.

Resumo Considerando um número crescente de casos de atendimento de emergência, provenientes do SARS-CoV-2, no Estado do Rio de Janeiro, o presente estudo se concentra no mapeamento da infraestrutura de saúde nos municípios do Estado, comparando o Índice de Eficiência em Estrutura antes (2016) e após a pandemia da COVID-19. O artigo preenche uma lacuna acadêmica ao informar aos especialistas, técnicos, formuladores e tomadores de decisão de políticas públicas de saúde, sobre a capacidade de cada localidade para enfrentar o problema. Para isso, calculamos o Índice de Eficiência da Estrutura (IEE), alocando os 92 municípios do Estado na curva de pandemia. Foi possível verificar que o Governo do Estado do Rio de Janeiro precisa começar a atuar na supressão da COVID-19, mantendo a política de abertura, ou reabertura, de leitos e aquisição de equipamentos. No entanto, também é necessário considerar as particularidades e deficiências de cada região, pois a política de transferência dos acamados para outras regiões com leitos disponíveis pode espalhar a doença.

A docking-based structural analysis of geldanamycin-derived inhibitor binding to human or Leishmania Hsp90.

Leishmaniasis is a neglected disease that affects millions of individuals around the world. Regardless of clinical form, treatment is based primarily on the use of pentavalent antimonials. However, such treatments are prolonged and present intense side effects, which lead to patient abandonment in many cases. The search for chemotherapeutic alternatives has become a priority. Heat Shock Protein 90 (Hsp90) inhibitors have recently come under investigation due to antiparasitic activity in Plasmodium sp., Trypanosoma sp. and Leishmania sp. Some of these inhibitors, such as geldanamycin and its analogs, 17-AAG and 17-DMAG, bind directly to Hsp90, thereby inhibiting its activity. Previous studies have demonstrated that different parasite species are more susceptible to some of these inhibitors than host cells. We hypothesized that this increased susceptibility may be due to differences in binding of Hsp90 inhibitors to Leishmania protein compared to host protein. Based on the results of the in silico approach used in the present study, we propose that geldanamycin, 17-AAG and 17-DMAG present an increased tendency to bind to the N-terminal domain of Leishmania amazonensis Hsp83 in comparison to human Hsp90. This could be partially explained by differences in intermolecular interactions between each of these inhibitors and Hsp83 or Hsp90. The present findings demonstrate potential for the use of these inhibitors in the context of anti-Leishmania therapy.

Immunogenicity of Potential CD4+ and CD8+ T Cell Epitopes Derived From the Proteome of Leishmania braziliensis.

Background: A safe and effective vaccine against human leishmaniasis still requires the identification of better antigens for immunization and adequate models to evaluate the immune response. To support vaccine development, this work tested the immunogenicity of 10 different peptides derived from the proteome of Leishmania braziliensis, which were selected by their in silico affinity to MHC complexes. Research design and Methods: Comparative cell proliferation assays were performed by culturing, in the presence of each peptide, PBMC cells from subclinical subjects (SC), cutaneous leishmaniasis patients with active disease (AD), post-treatment (PT) individuals, and healthy controls. Culture supernatants were then used for Th1, Th2, and Th17 cytokine measurements. Cells from selected PT samples were also used to assess the expression, by T cells, of the T-bet Th1 transcription factor. Results: A robust cell proliferation was observed for the SC group, for all the tested peptides. The levels of Th1 cytokines were peptide-dependent and had substantial variations between groups, where, for instance, IFN-γ and TNF levels were some of the highest, particularly on PT cultures, when compared to IL-2. On the other hand, Th2 cytokines displayed much less variation. IL-6 was the most abundant among all the evaluated cytokines while IL-4 and IL-10 could be found at much lower concentrations. IL-17 was also detected with variations in SC and AD groups. T-bet was up-regulated in CD4+ and CD8+ T cells from the PT group after stimulation with all peptides. Conclusions: The peptide epitopes can differentially stimulate cells from SC, AD, and PT individuals, leading to distinct immune responses.

Anti-hypersensitivity effects of the phthalimide derivative N-(4methyl-phenyl)-4-methylphthalimide in different pain models in mice.

The treatment of chronic pain remains a challenge for clinicians worldwide, independent of its pathogenesis. It motivates several studies attempting to discover strategies to treat the disease. The in silico analysis using molecular docking approach demonstrated that the phthalimide N-(4methyl-phenyl)-4-methylphthalimide (MPMPH-1) presented high affinity to adenylyl-cyclase enzyme (AC). It also prominently reduced the mechanical hypersensitivity of mice challenged by Forskolin, an AC activator. This effect lasted for up to 48h after Forskolin injection, presenting activity longer than MDL-12330A (AC inhibitor). MPMPH-1 was also effective in reducing the hypersensitivity induced by IL-1ß, bradykinin, prostaglandin E2 or epinephrine, chemical mediators that have, among others, AC as pivotal protein in their signalling cascade to induce mechanical-pain behaviour. The compound presented marked inhibition in inflammatory-pain models induced by carrageenan, lipopolysaccharide or complete Freund's adjuvant, including neutrophil migration inhibition. Furthermore, it also seems to act in both peripheral and pain central-control pathways, being also effective in reducing the persistent cancer-pain behaviour induced by melanoma cells in mice. MPMPH-1 could represent a promising pharmacological tool to treat acute and chronic painful diseases, with good bioavailability, local activity, and lack of locomotor-activity interference. Further studies are necessary to determine the exact mechanism of action but it seems to involve AC enzyme as possible target.

Efeito midriático da fenilefrina a 10% na comparação entre a autoinstilação de gota em olhos abertos e a vaporização em olhos fechados / Phenylephrine 10% mydriatic effect: comparison between self instillation of eye drop in open eyes and spray in closed eyes

RESUMO Objetivo: Comparar a eficácia fenilefrina a 10% aplicada pelo próprio paciente por vaporização em olho fechado em relação à instilação de gota em olho aberto em indivíduos que irão realizar exame de fundoscopia e avaliar o nível de dificuldade e a adequação técnica entre os métodos de administração. Métodos: Ensaio clínico controlado, randomizado e pareado realizado em 2014 envolvendo 100 olhos de 50 pacientes na Policlínica Ronaldo Gazolla - RJ, sem doenças oculares ou sistêmicas que comprometiam a dilatação pupilar. Os pacientes foram submetidos à instilação de 1 gota de fenilefrina a 10% e aplicação de vaporizador do mesmo midriático no olho contralateral. O olho em que se instilou o colírio permaneceu aberto, enquanto o olho vaporizado ficou fechado durante as aplicações da medicação. O diâmetro pupilar foi medido antes da aplicação, 10, 20 e 30 minutos após. O processo de instilação ou vaporização foi observado quanto a sua adequação técnica por um dos autores. Após o processo foi perguntado ao paciente questões pré-formuladas sobre a praticidade de ambos os métodos. Resultados: A diferença de midríase média entre os grupos de olhos avaliados em um determinado tempo foi no máximo 0,3 mm , o que não foi clinicamente ou estatisticamente significativo (ANOVA: F = 1,97 e p = 0,163609) . Porém, ao longo do tempo, a diferença entre o diâmetro da pupila no tempo inicial e no tempo de 30 minutos foi 1,15 mm para os olhos vaporizados e 1,58 mm para os olhos instilados com gotas (ANOVA: F = 129,22 e p ≤ 0,0001). Percentual de 60% dos pacientes tocaram a ponta do frasco de colírio nos olhos, enquanto que 12% tocaram o orifício na ponta do vaporizador com os dedos (p < 0,000001). Setenta de dois por cento (72%) consideraram a instilação de gotas fácil ou muito fácil enquanto 62% consideraram a vaporização em olho fechado fácil ou muito fácil (p = 0,238). Conclusão: A instilação de gotas em olhos abertos e a vaporização de olhos fechados da fenilefrina a 10% apresentou eficácia clínica semelhante. A vaporização foi mais segura e apresentou nível de dificuldade um pouco maior do que a instilação, apesar dos pacientes serem experientes para instilar gotas e inexperientes para vaporizar a medicação em olho fechado.

ABSTRACT Objective: To compare the effectiveness of phenylephrine 10% applied by a spray onto the eye closed over drop instillation onto an open eye on patients who will perform ophthalmoscopy and assess the level of difficulty and technical adequacy of the administration methods. Methods: The study was a clinical trial, controlled, randomized and paired, performed in 2014, involving 100 eyes of 50 patients in the Polyclinic Ronaldo Gazolla - RJ, with no ocular or systemic diseases that compromised the pupillary dilation. Patients underwent 10% phenylephrine eye drop instillation onto one open eye and spray application onto the other eye, which was closed. Pupillary diameter was measured before application and 10, 20, 30 minutes after. The process of instillation or vaporization was observed for its technical correctness by one of the authors. A questionnaire was asked to the patient about the difficulty of both methods after topical administration. Results: The average mydriasis difference between the eye groups assessed at a given time was at most 0.3 mm, which was not clinically or statistically significant (ANOVA: F = 1.97 and p = 0.163609). However, over time, the difference between the average pupil diameter before application and after 30 minutes was 1.15 mm to vaporized eyes and to 1.58 mm in eyes instilled with drops (ANOVA: F = 129, 22 and p ≤ 0.0001). Sixty per cent of patients touched the tip of the eye drop bottle onto the eye, while 12% touched the tip of the vaporizer with their fingers (p <0.000001). Seventy two percent (72%) considered the drops instillation easy or very easy, while 62% considered vaporization in a closed eye easy or very easy (p = 0.238). Conclusion: The instillation of drops phenylephrine 10% in open eyes and the vaporization onto closed eyes showed similar clinical efficacy. Vaporization was safer and a little more difficult than instillation, despite the patients being experienced for instilling drops and inexperienced to vaporize the medication in a closed eye.

Combination of In Silico Methods in the Search for Potential CD4(+) and CD8(+) T Cell Epitopes in the Proteome of Leishmania braziliensis.

The leishmaniases are neglected tropical diseases widespread throughout the globe, which are caused by protozoans from the genus Leishmania and are transmitted by infected phlebotomine flies. The development of a safe and effective vaccine against these diseases has been seen as the best alternative to control and reduce the number of cases. To support vaccine development, this work has applied an in silico approach to search for high potential peptide epitopes able to bind to different major histocompatibility complex Class I and Class II (MHC I and MHC II) molecules from different human populations. First, the predicted proteome of Leishmania braziliensis was compared and analyzed by modern linear programs to find epitopes with the capacity to trigger an immune response. This approach resulted in thousands of epitopes derived from 8,000 proteins conserved among different Leishmania species. Epitopes from proteins similar to those found in host species were excluded, and epitopes from proteins conserved between different Leishmania species and belonging to surface proteins were preferentially selected. The resulting epitopes were then clustered, to avoid redundancies, resulting in a total of 230 individual epitopes for MHC I and 2,319 for MHC II. These were used for molecular modeling and docking with MHC structures retrieved from the Protein Data Bank. Molecular docking then ranked epitopes based on their predicted binding affinity to both MHC I and II. Peptides corresponding to the top 10 ranked epitopes were synthesized and evaluated in vitro for their capacity to stimulate peripheral blood mononuclear cells (PBMC) from post-treated cutaneous leishmaniasis patients, with PBMC from healthy donors used as control. From the 10 peptides tested, 50% showed to be immunogenic and capable to stimulate the proliferation of lymphocytes from recovered individuals.

Structural design, synthesis and pharmacological evaluation of 4-thiazolidinones against Trypanosoma cruzi.

Chagas disease is an infection caused by protozoan Trypanosoma cruzi, which affects approximately 8-10million people worldwide. Benznidazole is the only drug approved for treatment during the acute and asymptomatic chronic phases of Chagas disease; however, it has poor efficacy during the symptomatic chronic phase. Therefore, the development of new pharmaceuticals is needed. Here, we employed the bioisosterism to modify a potent antiparasitic and cruzain-inhibitor aryl thiosemicarbazone (4) into 4-thiazolidinones (7-21). Compounds (7-21) were prepared by using a straightforward synthesis and enabled good to excellent yields. As a chemical elucidation tool, X-ray diffraction of compound (10) revealed the geometry and conformation of this class compounds. The screening against cruzain showed that 4-thiazolidinones were less active than thiosemicarbazone (4). However, the antiparasitic activity in Y strain trypomastigotes and host cell cytotoxicity in J774 macrophages revealed that compounds (10 and 18-21) are stronger and more selective antiparasitic agents than thiosemicarbazone (4). Specifically, compounds (18-20), which carry a phenyl at position N3 of heterocyclic ring, were the most active ones, suggesting that this is a structural determinant for activity. In infected macrophages, compounds (18-20) reduced intracellular amastigotes, whereas Benznidazole did not. In T. cruzi-infected mice treated orally with 100mg/kg of compound (20), a decreased of parasitemia was observed. In conclusion, we demonstrated that the conversation of thiosemicarbazones into 4-thiazolidinones retains pharmacological property while enhances selectivity.

An expression of uncertainty and its application to positioning: a quality-metric and optimal ranges for the identification of cells with RFID.

Here we devise an approach to model error and its propagation. Without approximations, we define the uncertainty of a measurement as its maximum possible error (maper). Thus, we propose and solve analytically two optimization problems. The one designed to determine the uncertainty of a measurement, the other specifically designed to optimize the accuracy of a RFID location system. The usefulness of this general approach is shown by applying it to the particular instance of estimating the coordinates of a person in real-time using RFID devices. This way, exact formulae to evaluate the quality of this measurement are mathematically deduced, which is useful, for example, to predict whether an inexpensive RFID location technology can meet a desired quality standard or not. The second optimization problem proposed here defines an optimal range (orange) for the RFID devices employed. Again, analytically, its exact formulae were derived. We propose an approach to distribute RFID tags for a positioning system based solely on RFID technology. In the light of the formulae, its quality is good enough as to locate emergency phone calls in real time. We found that key to an optimal performance is the range used and the distance between consecutive tags.

Trypanosoma cruzi transmission in a captive primate unit, Rio de Janeiro, Brazil.

A breeding in captivity program of neotropical primates for subsequent reintroduction in nature is in progress at the Primatology Center of Rio de Janeiro (CPRJ). Almost 200 animals of 20 species that include both wild captured animals and specimens born in captivity are maintained in CPRJ. Here, we examined 198 primates of CPRJ for infection with the protozoan parasite Trypanosoma cruzi. The animals included 18 species of eight genera. We also performed an "ad lib" search for triatomines that could be incriminated as putative transmitters of the protozoan in this scenario. Anti-T. cruzi antibodies were observed (by indirect immunofluorescence assay-IFA) in 40 monkeys (26.5%). Four Panstrongylus megistus were collected in the monkey's food storage room near the cages and in human dwellings in the proximity to CPRJ. T. cruzi were isolated from nine primates of two genera (Leontopithecus and Saguinus) and from two individuals of the vector P. megistus. The transmission inside the cages could be attested by the isolation of the T. cruzi from primates born in captivity. Multi-locus enzyme electrophoresis (MLEE) demonstrated that the two isolates from Saguinus bicolor bicolor displayed a zymodeme 1 profile in four out of five tested enzymes, while all isolates derived from Leontopithecus showed zymodeme 2 for four out of the five tested enzymes. Mini-exon gene analysis genotyped all isolates as T. cruzi II, which is associated with human disease in Brazil. A wild primate unit such as CPRJ, located inside the forest and near to human dwellings and with T. cruzi II infected animals, deserves a careful surveillance in order to prevent expansion of the infection.