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1.
J Nutr ; 154(9): 2871-2886, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39069270

RESUMO

BACKGROUND: Multiple studies have demonstrated associations between the early-life gut microbiome and incidence of inflammatory and autoimmune disease in childhood. Although microbial colonization is necessary for proper immune education, it is not well understood at a mechanistic level how specific communities of bacteria promote immune maturation or drive immune dysfunction in infancy. OBJECTIVES: In this study, we aimed to assess whether infant microbial communities with different overall structures differentially influence immune and gastrointestinal development in healthy mice. METHODS: Germ-free mice were inoculated with fecal slurries from Bifidobacterium longum subspecies infantis positive (BIP) or B. longum subspecies infantis negative (BIN) breastfed infants; half of the mice in each group were also supplemented with a pool of human milk oligosaccharides (HMOs) for 14 d. Cecal microbiome composition and metabolite production, systemic and mucosal immune outcomes, and intestinal morphology were assessed at the end of the study. RESULTS: The results showed that inoculation with a BIP microbiome results in a remarkably distinct microbial community characterized by higher relative abundances of cecal Clostridium senu stricto, Ruminococcus gnavus, Cellulosilyticum sp., and Erysipelatoclostridium sp. The BIP microbiome produced 2-fold higher concentrations of cecal butyrate, promoted branched short-chain fatty acid (SCFA) production, and further modulated serotonin, kynurenine, and indole metabolism relative to BIN mice. Further, the BIP microbiome increased the proportions of innate and adaptive immune cells in spleen, while HMO supplementation increased proliferation of mesenteric lymph node cells to phorbol myristate acetate and lipopolysaccharide and increased serum IgA and IgG concentrations. CONCLUSIONS: Different microbiome compositions and HMO supplementation can modulate SCFA and tryptophan metabolism and innate and adaptive immunity in young, healthy mice, with potentially important implications for early childhood health.


Assuntos
Suplementos Nutricionais , Microbioma Gastrointestinal , Leite Humano , Oligossacarídeos , Animais , Leite Humano/química , Oligossacarídeos/farmacologia , Humanos , Camundongos , Microbioma Gastrointestinal/efeitos dos fármacos , Bifidobacterium , Fezes/microbiologia , Feminino , Ceco/microbiologia , Ruminococcus , Ácidos Graxos Voláteis/metabolismo , Lactente , Clostridiales
2.
Parasitol Res ; 123(7): 261, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38967653

RESUMO

Ticks are blood-sucking arthropods that can transmit pathogens to their host. As insular ecosystems can enhance tick-host interactions, this study aimed to understand tick diversity, pathogen presence, and their respective associations in the Azores and Madeira archipelagos. Unfed or partially engorged ticks (n = 120) were collected from 58 cats and dogs in the Azores (n = 41 specimens) and Madeira (n = 79 specimens) from November 2018 to March 2019. Vector identification was based on morphology and molecular criteria. For pathogen sequencing, 18S gene fragment for Babesia/Hepatozoon and gltA for Rickettsia were performed. Sequence data was explored using BLAST and BLAST and phylogenetic inference tools. In the Azores, Ixodes hexagonus, I. ventalloi, and Rhipicephalus sanguineus (n = 6; 14.6%, n = 6; 14.6%, and n = 29; 70.7% respectively) were found and in Madeira I. ricinus and R. sanguineus (n = 78, 98.7%; and n = 1, 1.3%; respectively) were identified. Tick COI markers confirmed species highlighting confirmation of R. sanguineus s.s. and genotype A of I. ventalloi. In the Azores Islands, the detected Rickettsia massiliae was linked to R. sanguineus (dogs and cats) and I. hexagonus (dogs), and in Madeira Island, R. monacensis (dogs) and Hepatozoon silvestris (cats) were found associated with I. ricinus. Further, I. ventalloi presence in the Azores expands west its known range, and Hepatozoon silvestris in Madeira may suggest that I. ricinus could have a role as a potential vector. Finally, as R. massiliae and R. monacensis presence underlines public health risks, surveillance by health authorities is crucial as pathogen-tick interactions may drive disease spread, therefore monitoring remains pivotal for disease prevention.


Assuntos
Babesia , Rickettsia , Animais , Açores , Gatos , Rickettsia/isolamento & purificação , Rickettsia/genética , Rickettsia/classificação , Babesia/genética , Babesia/isolamento & purificação , Babesia/classificação , Cães , Doenças do Cão/parasitologia , Doenças do Cão/microbiologia , Filogenia , Doenças do Gato/parasitologia , Doenças do Gato/microbiologia , Ixodes/microbiologia , Ixodes/parasitologia , Infestações por Carrapato/veterinária , Infestações por Carrapato/parasitologia , Rhipicephalus sanguineus/microbiologia , Rhipicephalus sanguineus/parasitologia , Coccídios/genética , Coccídios/isolamento & purificação , Coccídios/classificação , Eucoccidiida/genética , Eucoccidiida/isolamento & purificação , Eucoccidiida/classificação
3.
J Org Chem ; 88(15): 11140-11149, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37463494

RESUMO

An efficient and controlled site-selective annulation of 3,5-diethoxycarbonyl 4-hydrazonyl pyrazoles is described. The relative proportion of the products is affected by hydrazone intermediate configuration, reaction temperature, and Lewis acid employed. At a temperature of 110-120 °C, the reaction preferentially afforded 1H-pyrazolo[3,4-d]pyridazin-7(6H)-ones, whereas using Yb(OTf)3 in MeCN reflux, 2H-pyrazolo[3,4-d]pyridazin-7(6H)-ones were favored. Computational investigations were performed to clarify the mechanism and the origin of the regiodivergence.

4.
J Org Chem ; 87(13): 8544-8550, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35687873

RESUMO

A simple, efficient and highly regioselective method for the preparation of 3,4- and 4,5-disubstituted N-methylpyrazoles in a one-pot procedure is reported. The methodology developed was based on the regiochemical control of the reaction of 4-acyl-1H-pyrrole-2,3-diones and methylhydrazine with an influence of the addition or absence of acid and the substrate structure.


Assuntos
Monometilidrazina , Pirróis , Pirróis/química
5.
Bioorg Med Chem ; 29: 115835, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33214037

RESUMO

A new one-pot two-step sequential methodology for synthesis of novel 3-carboxyethyl 4-[(tert-butylamino)methyl]-N-arylpyrazole derivatives is reported. One-pot transformation of ß-enamino diketones and arylhydrazines generated 4-iminium-N-arylpyrazole salt intermediates in situ, which were easily transformed into 4-[(tert-butylamino)methyl]-N-arylpyrazole derivatives by NaBH3CN. The products could be isolated in the free or hydrochloride salt forms. Also, it was possible to obtain the products in the zwitterionic form by ester group hydrolysis. Furthermore, all synthesised compounds were evaluated in vitro against a panel of eight human tumor cell lines. The 4-[(tert-butylamino)methyl]-N-arylpyrazole derivatives were much more powerful than the hydrochloride and zwitterionic forms. Moreover, the results suggest that the N-aryl group at the pyrazole ring is vital for modulating antiproliferative activity. The 3-carboxyethyl 4-[(tert-butylamino)methyl]-N-phenylpyrazoles 3a-g exhibited higher inhibitory activities against OVCAR-3, with GI50 values of 0.013-8.78 µM, and lower inhibitory activities against normal human cell lines. Molecular docking was performed to evaluate the probable binding mode of 3a into active site of CDK2.


Assuntos
Antineoplásicos/farmacologia , Descoberta de Drogas , Neoplasias Ovarianas/tratamento farmacológico , Pirazóis/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Neoplasias Ovarianas/patologia , Pirazóis/síntese química , Pirazóis/química , Relação Estrutura-Atividade
6.
Bioorg Chem ; 114: 105082, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34147880

RESUMO

Trypanosoma cruzi and Leishmania species are causative agents of Chagas disease and Leishmaniasis, respectively, known as Neglected Tropical Diseases. Up to now, the treatments are inadequate and based on old drugs. Thus, we report herein the discovery of 1,3,4,5-tetrasubstituted pyrazole derivatives that presented potent and selective inhibition against promastigote forms of L. amazonensis, and epimastigote forms of T. cruzi. The structure-activity relationship led to the identification of three compounds (2m, 2n and 2p) with an in vitro IC50 of 7.4 µM (selective index - SI ≥ 133.0), 3.8 µM (SI in the range of 148.4 to 200.8), and 7.3 µM (SI in the range of 87.2 to 122.4) against L. amazonensis, respectively. Also, those compounds exhibited in vitro IC50 of 9.7 µM (SI ≥ 101.5), 4.5 µM (SI in the range of 125.3 to 169.6) and 17.1 µM (SI in the range of 37.2 to 52.2) against T. cruzi, respectively. A preliminary study about the reaction mechanism in promastigotes showed that 2n caused an increase of the production of ROS and of lipid storage bodies. Furthermore, 2n induced abnormalities in the flagellum that may have an impact on the parasite motility.


Assuntos
Descoberta de Drogas , Leishmania/efeitos dos fármacos , Pirazóis/farmacologia , Tripanossomicidas/farmacologia , Relação Dose-Resposta a Droga , Estrutura Molecular , Testes de Sensibilidade Parasitária , Pirazóis/síntese química , Pirazóis/química , Relação Estrutura-Atividade , Tripanossomicidas/síntese química , Tripanossomicidas/química
7.
Drug Dev Res ; 82(2): 230-240, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32996619

RESUMO

In this article, a series of 29 new pyrimidine N-acylhydrazone hybrids were synthesized and evaluated in vitro against Leishmania amazonensis and Trypanosoma cruzi protozoa that cause the neglected diseases cutaneous leishmaniasis and Chagas disease, respectively. Eight of the target compounds showed significant antiprotozoal activities with IC50 values in 4.3-33.6 µM range. The more active compound 4f exhibited selectivity index greater than 15 and drug-like properties based on Lipinski's rule.


Assuntos
Antiparasitários/farmacologia , Hidrazonas/farmacologia , Leishmania braziliensis/efeitos dos fármacos , Pirimidinas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Antiparasitários/química , Humanos , Hidrazonas/química , Leishmania braziliensis/fisiologia , Pirimidinas/química , Trypanosoma cruzi/fisiologia
8.
Clin Otolaryngol ; 46(3): 570-576, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33449440

RESUMO

OBJECTIVE: To describe and compare the findings of endoscopic sensory assessment in COPD patients and healthy controls. DESIGN: A prospective cross-sectional study. SETTING: Otorhinolaryngology outpatient clinic at a university hospital. PARTICIPANTS: 27 adults with COPD and 11 age-matched healthy controls. MAIN OUTCOME MEASURES: Group differences in light touch endoscopic tests of pharyngeal and laryngeal sensation, controlling for pooled salivary secretions in the pharynx and laryngo-pharyngeal reflux as measured by the Reflux Finding Score (RFS). RESULTS: A significant difference in laryngeal sensation was found between the study groups (P = .047), with reduced laryngeal sensation in the COPD patients. Additionally, a significant relationship was found between impaired oropharyngeal sensation and the presence of pooled salivary secretions in the pharynx (P = .018), especially in the pyriform sinuses (P = .012). No differences in the frequency of abnormal RFSs were found between groups. CONCLUSION: Individuals with COPD were significantly more likely to present with impaired laryngeal sensation. Additionally, impaired sensation in the oropharynx was associated with pooled salivary secretions in the pharynx.


Assuntos
Laringe/fisiopatologia , Faringe/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Transtornos de Sensação/fisiopatologia , Idoso , Estudos Transversais , Feminino , Refluxo Gastroesofágico/fisiopatologia , Humanos , Laringoscopia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Saliva/metabolismo
9.
Bioorg Med Chem Lett ; 30(14): 127244, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32527546

RESUMO

Paracoccidioidomycosis is an endemic mycosis in Latin America for which there is a high mortality rate and limited treatment options. There are no specific drugs to treat the systemic disease. Thus, there is a need for further studies focused on the development of specific drugs. In this work we synthesized new hybrids pyrimido[4,5-d]pyridazinone-N-acylhydrazone (5a-p) by simple methodologies with good yields. The antifungal activity of compounds was evaluated against P. brasiliensis (Pb18) and Candida spp. Compounds 5a, 5f, 5i, 5 k, 5m and 5n showed significant inhibition against Pb18 with MIC of 0.125 to 64 µg mL-1. Compound 5a is the most promising, showing potent fungicidal profile with MFC of 0.5 µg mL-1, synergic effect with amphotericin B, besides showing no toxicity against HeLa and Vero cells.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Hidrazonas/farmacologia , Paracoccidioides/efeitos dos fármacos , Piridazinas/farmacologia , Animais , Antifúngicos/síntese química , Antifúngicos/química , Chlorocebus aethiops , Relação Dose-Resposta a Droga , Células HeLa , Humanos , Hidrazonas/síntese química , Hidrazonas/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Piridazinas/síntese química , Piridazinas/química , Relação Estrutura-Atividade , Células Vero
10.
Org Biomol Chem ; 18(13): 2524-2537, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32196053

RESUMO

A simple and efficient methodology for highly regioselective synthesis of azomethine pyrazoles and isoxazoles containing a trifluoromethyl group is reported. The cyclocondensation of trifluoromethylated ß-enamino diketones (TBED) with phenylhydrazine and hydroxylamine hydrochloride, in the presence of BF3, provided 5-aryl-4-[(tert-butyl)iminomethyl]-3-trifluoromethylazoles by aza-Michael-type 1,2-addition. The scope of the reaction was expanded by transimination with arylamines in a one-pot method starting from TBED. Thus, 83 novel 4-[(alkyl/aryl)iminomethyl]-3-trifluoromethylazoles were obtained with high regioselectivity and in yields of 51 to 89%.

11.
Bioorg Med Chem ; 28(12): 115549, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32503692

RESUMO

The inflammatory response is the reaction of living tissue to an injury of a foreign nature, such as infection and irritants, and occurs as part of the body's natural defence response. Compounds capable of inhibiting cyclooxygenase (COX) enzymes, especially COX-2, have great potential as anti-inflammatory agents. Herein we present the regioselective synthesis of 49 novel compounds based on the 2-pyridone nucleus. The topical anti-inflammatory activity of seventeen compounds was evaluated in mice by croton oil (CO) induced ear edema assay. Most of the compounds exhibited a high level of in vivo anti-inflammatory activity, reducing ear edema and myeloperoxidase (MPO) activity. The most active compounds (2a and 7a) were inhibitors of COX enzymes. Compound 2a selectively inhibited the COX-2, while 7a was nonselective. Further, the compound 2a showed effective binding at the active site of COX-2 co-crystal by docking molecular study.


Assuntos
Anti-Inflamatórios/síntese química , Piridonas/química , Animais , Anti-Inflamatórios/metabolismo , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Sítios de Ligação , Domínio Catalítico , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ciclo-Oxigenase 2/química , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase 2/síntese química , Inibidores de Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase 2/farmacologia , Inibidores de Ciclo-Oxigenase 2/uso terapêutico , Edema/induzido quimicamente , Edema/tratamento farmacológico , Humanos , Camundongos , Conformação Molecular , Simulação de Acoplamento Molecular , Peroxidase/metabolismo , Piridonas/metabolismo , Piridonas/uso terapêutico , Estereoisomerismo , Relação Estrutura-Atividade
12.
J Dairy Res ; 87(4): 416-423, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33168108

RESUMO

The study included two experiments. In the first, 24 lactating Saanen dairy goats received low-energy diet without vitamin supplements. Twelve goats received a daily IV injection of 2,4- thiazolidinedione (TZD), others received saline injection. A week later, 6 goats from each treatment were challenged with intramammary infusion (IMI) of saline (CTRL) or Streptococcus uberis. In the second experiment, 12 Saanen lactating dairy goats received supplemental vitamins to reach NRC recommendation level. Six goats in each group were injected with TZD or saline daily, and 14 d later received Streptococcus uberis IMI in the right half of the udder. The hypotheses were (1) TZD does not affect the level of retinol in blood, and (2) the fatty acid profile is affected by the interaction between mammary infection and TZD in dairy goats. In the first experiment blood samples were collected on d -7, -2, 1, 2, 12 and milk samples were collected on d -8, 1, 4, 7, and 12, both relative to IMI. In the second experiment, blood samples were collected on d -15, 0, 1, and 10 relative to IMI. Milk and serum samples were analyzed for retinol, α-tocopherol and fatty acid profile. Serum retinol and ß-carotene concentrations were higher in the second experiment compared to the first. Serum ß-carotene and α-tocopherol were greater in TZD than CTRL and there was a TZD × time interaction in the first experiment. In addition, the TZD × time interaction showed that the milk fatty acid were reduced in C16 : 0 while C18 : 3 n3 while total omega 3 fatty acids were increased, as well as with minor effect on preventing a transient increase in α-tocopherol in milk. Overall, the TZD may affect the lipid-soluble vitamins and fatty acid profile, potentially altering immune responses, during mastitis in dairy goats.


Assuntos
Doenças das Cabras/microbiologia , Mastite/veterinária , Infecções Estreptocócicas/veterinária , Streptococcus , Tiazolidinedionas/farmacologia , Vitamina A/sangue , Animais , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Feminino , Cabras , Hipoglicemiantes/farmacologia , Mastite/microbiologia , Leite/química , Infecções Estreptocócicas/microbiologia , Vitamina A/administração & dosagem , Vitamina A/farmacologia , alfa-Tocoferol/sangue , beta Caroteno/sangue
13.
Eur J Neurosci ; 49(12): 1673-1683, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30667546

RESUMO

Attention deficit and hyperactivity disorder (ADHD) is characterized by impaired levels of hyperactivity, impulsivity, and inattention. Adenosine and endocannabinoid systems tightly interact in the modulation of dopamine signaling, involved in the neurobiology of ADHD. In this study, we evaluated the modulating effects of the cannabinoid and adenosine systems in a tolerance to delay of reward task using the most widely used animal model of ADHD. Spontaneous Hypertensive Rats (SHR) and Wistar-Kyoto rats were treated chronically or acutely with caffeine, a non-selective adenosine receptor antagonist, or acutely with a cannabinoid agonist (WIN55212-2, WIN) or antagonist (AM251). Subsequently, animals were tested in the tolerance to delay of reward task, in which they had to choose between a small, but immediate, or a large, but delayed, reward. Treatment with WIN decreased, whereas treatment with AM251 increased the choices of the large reward, selectively in SHR rats, indicating a CB1 receptor-mediated increase in impulsive behavior. An acute pre-treatment with caffeine blocked WIN effects. Conversely, a chronic treatment with caffeine increased the impulsive phenotype and potentiated the WIN effects. The results indicate that both cannabinoid and adenosine receptors modulate impulsive behavior in SHR: the antagonism of cannabinoid receptors might be effective in reducing impulsive symptoms present in ADHD; in addition, caffeine showed the opposite effects on impulsive behavior depending on the length of treatment. These observations are of particular importance to consider when therapeutic manipulation of CB1 receptors is applied to ADHD patients who consume coffee.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Cafeína/farmacologia , Agonistas de Receptores de Canabinoides/farmacologia , Antagonistas de Receptores de Canabinoides/farmacologia , Comportamento Impulsivo/efeitos dos fármacos , Psicotrópicos/farmacologia , Animais , Benzoxazinas/farmacologia , Modelos Animais de Doenças , Masculino , Morfolinas/farmacologia , Naftalenos/farmacologia , Piperidinas/farmacologia , Antagonistas de Receptores Purinérgicos P1/farmacologia , Pirazóis/farmacologia , Distribuição Aleatória , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY
14.
Exp Appl Acarol ; 75(1): 107-128, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29605833

RESUMO

A multigene phylogeny including 24 Rhipicephalus species from the Afrotropical and Mediterranean regions, based on mitochondrial DNA genes (COI, 12S and 16S), was constructed based on Bayesian inference and maximum likelihood estimations. The phylogenetic reconstruction revealed 31 Rhipicephalus clades, which include the first molecular records of Rhipicephalus duttoni (Neumann), and Rhipicephalus senegalensis (Koch). Our results support the R. pulchellus, R. evertsi and R. pravus complexes as more phylogenetically close to Rhipicephalus (Boophilus) than to the remaining Rhipicephalus clades, suggesting two main monophyletic groups within the genus. Additionally, the phenotypic resembling R. sanguineus s.l. and Rhipicephalus turanicus (Pomerantsev) are here represented by nine clades, of which none of the R. turanicus assemblages appeared as distributed in the Iberian Peninsula. These results not only indicate that both species include more cryptic diversity than the already reported, but also suggest that R. turanicus distribution is less extended than previously anticipated. This analysis allowed to improve species identification by exposing cryptic species and reinforced mtDNA markers suitability for intra/inter-species clarification analyses. Incorporating new species molecular records to improve phylogenetic clarification can significantly improve ticks' identification methods which will have epidemiologic implications on public health.


Assuntos
Distribuição Animal , DNA Mitocondrial/genética , Filogenia , Rhipicephalus/classificação , África Subsaariana , Animais , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , Masculino , Região do Mediterrâneo , RNA Ribossômico/genética , RNA Ribossômico 16S/genética , Rhipicephalus/anatomia & histologia , Rhipicephalus/genética
15.
J Org Chem ; 82(23): 12590-12602, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29094945

RESUMO

An alternative highly regioselective synthetic method for the preparation of 3,5-disubstituted 4-formyl-N-arylpyrazoles in a one-pot procedure is reported. The methodology developed was based on the regiochemical control of the cyclocondensation reaction of ß-enamino diketones with arylhydrazines. Structural modifications in the ß-enamino diketone system allied to the Lewis acid carbonyl activator BF3 were strategically employed for this control. Also a one-pot method for the preparation of 3,5-disubstituted 4-hydroxymethyl-N-arylpyrazole derivatives from the ß-enamino diketone and arylhydrazine substrates is described.

16.
Beilstein J Org Chem ; 13: 257-266, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28326135

RESUMO

The syntheses of several polyazaheterocycles are demonstrated. The cyclocondensation reactions between ß-enaminodiketones [CCl3C(O)C(=CNMe2)C(O)-CO2Et] and aromatic amidines resulted in glyoxalate-substituted pyrido[1,2-a]pyrimidinone, thiazolo[3,2-a]pyrimidinone and pyrimido[1,2-a]benzimidazole. Pyrazinones and quinoxalinones were obtained through the reaction of these glyoxalates with ethylenediamine and 1,2-phenylenediamine derivatives. On the other hand, the reaction of glyoxalates with amidines did not lead to the formation of imidazolones, but rather N-acylated products were obtained. All the products were isolated in good yields. DFT-B3LYP calculations provided HOMO/LUMO coefficients, charge densities, and the stability energies of the intermediates, and from these data it was possible to explain the regiochemistry of the products obtained. Additionally, the data were a useful tool for elucidating the reaction mechanisms.

17.
Parasitol Res ; 115(4): 1567-72, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26755362

RESUMO

Schistosomiasis is the major neglected tropical helminthic disease worldwide. Current knowledge on the epidemiology of schistosomiasis in Guinea-Bissau is scarce and regarding to the absence of Schistosoma haematobium (S.h.). Therefore, a pilot study was undertaken to assess the prevalence and morbidity due to S.h. infection in randomly selected 90 children and adolescents aged 6 to 15 years. Prevalence of S.h. infection was 20.00 % (18/90). Microhematuria was observed in 61.11 % (11/18) of S.h.-egg-excreting vs. 37.50 % (27/72) of non-S.h.-egg-excreting children p ≤ 0.01. Body mass index (BMI) was less than 15 kg/m(2) in 52/90 (57.78 %) of all children and adolescents, but this proportion increased to 66.67 % (12/18) in S.h.-infected children who were more frequently stunted and wasted than in non-infected children. The mean weight-for-age Z score (WAZ) was reduced in S.h. infected as compared to non-infected children (-1.48 ± 1.08 SD vs. -0.80 ± 1.11 SD; p ≤ 0.01). To our knowledge, this is the first epidemiologic report on S. haematobium infection in Guinea-Bissau since 22 years. Even in this relatively small study sample, it appears that S. haematobium, besides the well-known symptoms such as hematuria, leads to significant, albeit commonly unacknowledged morbidity such as stunting and wasting. These observations underscore the notion that this vulnerable but neglected population urgently needs to be targeted for implementation of measures for treatment and control.


Assuntos
Schistosoma haematobium/isolamento & purificação , Esquistossomose Urinária/epidemiologia , Adolescente , Animais , Criança , Feminino , Geografia , Guiné-Bissau/epidemiologia , Humanos , Masculino , Morbidade , Doenças Negligenciadas , Estado Nutricional , Projetos Piloto , Prevalência , Esquistossomose Urinária/parasitologia
18.
Exp Appl Acarol ; 70(4): 455-468, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27812830

RESUMO

Although some studies have already been performed on Rhipicephalus sanguineus (Latreille) populations, there is still much disarray around its taxonomic classification. Rhipicephalus sanguineus, which is also known as " (brown dog tick) is a three-host tick that parasitizes many vertebrates, including occasional human hosts. It presents a worldwide distribution and is a vector of zoonosis with acknowledged public health importance. In Western Europe, R. turanicus (Pomerantsev) share many phenotypic features and is genetically closely related to R. sanguineus. Additionally, as these species are sympatric, they can be easily misidentified. However, by means of a thorough morphological traits analysis, it is possible to distinguish both species, especially resorting to scanning electron microscopy. This study was conducted using stereoscopic and SEM analyses, both associated with morphometric analysis, in order to help clarify the taxonomic status of this species complex. For that purpose, specimens resembling R. sanguineus were collected from dogs of the Midwestern Iberian Peninsula. Identification was performed based on taxonomical key characteristics. The obtained results allowed the authors to agree that a great morphological variability is found within R. sanguineus-like Iberian populations. Nevertheless, R. turanicus is easily identified by morphologic analysis, especially using reference specimens, and its presence in Portugal is suggested.


Assuntos
Rhipicephalus sanguineus/anatomia & histologia , Rhipicephalus sanguineus/classificação , Animais , Feminino , Masculino , Microscopia Eletrônica de Varredura , Portugal , Rhipicephalus sanguineus/ultraestrutura
19.
J Phys Chem A ; 119(10): 2111-21, 2015 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-25679501

RESUMO

This study reports the results of ab initio and density functional theory (DFT) electronic structure calculations as well as (3)J(HH) experimental and calculated coupling constant data obtained in the investigation of the conformational equilibrium of 3-halo-derivatives of 1-methylpyrrolidin-2-one. The five-membered ring assumes an envelope conformation owing to the plane of formation of the O═C-N-R bond, with C4 forming the "envelope lid". When the conformation changes, the "lid" alternates between positions above and below the amide plane. The α-carbonyl halogen assumes two positions: a pseudo-axial and a pseudo-equatorial. In the gaseous phase, the calculations indicate that the pseudo-axial conformer is more stable and preferable going down the halogen family. Natural bond orbital analysis showed that electronic delocalization is significant only for the iodo derivative. In the other derivatives, the electrostatic repulsion between oxygen and the halogen determines the conformational equilibrium. When the solvated molecule was taken into account, the pseudo-equatorial conformer population increased with the relative permittivity of the solvent. This variation was strong in the fluoro derivative, and the preference was inverted. In the chlorine derivative, the two populations became closer in methanol and acetonitrile. In the bromine and iodine derivatives, the percentage of pseudo-equatorial conformer increased only slightly owing to the dipole moment of the conformation: the pseudo-equatorial conformation has a greater dipole moment and thus is stable in media with high relative permittivity.

20.
BMC Evol Biol ; 14: 213, 2014 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-25301477

RESUMO

BACKGROUND: Glaciations were recurrent throughout the Quaternary and potentially shaped species genetic structure worldwide by affecting population dynamics. Here, we implemented a multi-model inference approach to recover the distribution dynamics and demographic history of a Neotropical savanna tree, Tabebuia aurea (Bignoniaceae). Exploring different algorithms and paleoclimatic simulations, we used ecological niche modelling to generate alternative hypotheses of potential demographic changes through the last glacial cycle and estimated genetic parameters using coalescent modelling. RESULTS: Comparing predictions from demographic hypotheses with genetic parameters of modern populations, our findings revealed a likely scenario of population decline, with spatial displacement towards Northeast Brazil from the last glacial maximum to the mid-Holocene. Subsequently, populations expanded in response to the return of the climatically suitable conditions in Central-West Brazil. Nevertheless, a wide historical refugium across Central Brazil likely maintained large populations connected throughout time. The expected genetic signatures from such predicted distribution dynamics are also corroborated by spatial genetic structure observed in modern populations. CONCLUSION: By exploring uncertainties inherent in multiple working hypotheses, we have shown that multi-model inference is a fruitful and efficient approach to recover the nature, timing and geographical context of the Tabebuia aurea population dynamic in response to the Quaternary climate changes.


Assuntos
Bignoniaceae/classificação , Bignoniaceae/genética , Brasil , Mudança Climática , Variação Genética , Pradaria , Árvores
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