RESUMO

The title complex, [Cu(C8H18NO5)Cl] or [Cu(H4bis-tris-)Cl], was obtained starting from the previously reported [Cu(H5bis-tris-)Cl]Cl compound. The deprotonation of the amino-polyol ligand H5bis-tris {[bis-(2-hy-droxy-eth-yl)amino]-tris-(hy-droxy-meth-yl)methane, C8H19NO5} promotes the formation of a very strong O-H⋯O inter-molecular hydrogen bond, characterized by an H⋯O separation of 1.553 (19) Šand an O-H⋯O angle of 178 (4)°. The remaining hy-droxy groups are also engaged in hydrogen bonds, forming R 2 2(8), R 4 4(16), R 4 4(20) and R 4 4(22) ring motifs, which stabilize the triperiodic supra-molecular network.

RESUMO

This study is aimed at evaluating the effect of different extenders on the cryopreservation of semen from Africanized honeybees (A. mellifera). Semen from honeybee drones from 10 different colonies was obtained by endophallus exposure technique and immediately evaluated for motility, viability using fluorescent probes, functional membrane integrity using the water test, and morphology. Samples from each colony were divided in three aliquots and subjected to a dilution ratio of 12:1 (diluent: semen) using Tris, Tris + egg yolk (Tris+EY), and Collins extender. Samples were cryopreserved and stored in liquid nitrogen for one week and then rewarmed and reevaluated. Immediate dilution provoked no significant effect on sperm motility and functional membrane integrity, regardless of the extender used; however, the greatest values (P < 0.05) for normal sperm morphology were found at the use of isolate Tris (69.3 ± 1.9%). After thawing, there were no significant differences among extenders with relation to the preservation of sperm motility, viability, and functional membrane integrity, but the Tris extender provided the highest post-thawing values (P < 0.05) for sperm normal morphology (49.2 ± 4.9%) while the Collins extender provoked the highest amounts (P < 0.05) of curled tail defects (67.5 ± 3.2%). Moreover, the Tris was the only extender at preserving the proportion of normal sperm after thawing similar to what was verified for fresh samples. In summary, we suggest the use of a Tris-based extender for the cryopreservation of Africanized honeybee semen.

RESUMO

The use of assisted reproductive techniques, such as chilled semen, contributes to the maintenance and genetic improvement of canine breeding. The INRA-96 extender is a commercially available, chemically defined medium that was initially developed for the preservation of equine semen and exhibits preservation potential in the canine species. This research aims to evaluate the INRA-96 extender as an alternative for the short-term preservation of canine semen in terms of sperm quality parameters such as motility and kinetic parameters, integrity and functionality of the plasma membrane in fresh and chilled-rewarmed samples, as well as the sperm-binding ability using the perivitelline membrane of the chicken egg as an indicator of the fertilizing capacity of the preserved semen. A total of 18 ejaculates from 9 French bulldogs (two ejaculates per dog) were collected and divided into two aliquots that were diluted in Tris-egg yolk 20% (control) or INRA-96 to a final concentration of 100 × 106 sperm/mL. Samples were refrigerated in a biological incubator at 5°C and evaluated at 0, 24 and 48 h time points. Comparing the two treatments after 48 h of refrigeration, both extenders showed similar values (p < .5) for the majority of kinetic parameters, with the INRA-96 group promoting a total motility of 88.1 ± 2.9%. In addition, the morphology, integrity and functionality of the plasma membrane were preserved above 70% in this group. Dilution with INRA-96 also provided a significantly higher amount of sperm bound (256.2 ± 21.1) to the perivitelline membrane of the egg yolk compared to the sperm-binding rates (p < .05) achieved at the use of Tris-egg yolk (215.2 ± 21 bound spermatozoa) at 48 h. Our study proved similar functional properties of dog sperm cells treated with INRA-96 in comparison to commonly used home-made Tris-based extender during short-time storage.

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O uso de diluentes adequados é importante para o sucesso da inseminação artificial. O objetivo deste estudo foi avaliar a eficiência de diluentes em diferentes temperaturas. Foram utilizados os seguintes diluentes: Beltsville Thwaing Solution (BTS); TRIS (Tris-hidroximetil-aminometano - H2NC(CH2OH)3); TRIS + gema de ovo (TGO) e Leite em pó desnatado (LPD). Cinquenta ejaculados foram analisados quanto ao vigor, à motilidade, à funcionalidade de membrana e à atividade mitocondrial. Os diluentes TGO e LPD mantiveram os maiores valores para vigor e motilidade a 10 °C, em comparação aos demais tratamentos (p<0,05). A 17 °C, esses diluentes apresentaram resultados melhores de vigor e motilidade em relação aos demais, somente até D1 (p<0,05). A partir de D2, o BTS mostrou-se como o melhor diluente para a preservação dessas características. Maior percentual de espermatozoides com membrana funcional foi observado no TGO a 10 °C, seguido do LPD, BTS e TRIS (p<0,05). A 17 °C, o BTS manteve essa característica, exceto em D0, em que o TGO e o LPD apresentaram melhores resultados. Quanto a atividade mitocondrial, maiores valores foram observados a 10 °C no TGO em todos os dias de análise e em D0 à temperatura de 17 °C. O diluente TRIS + gema de ovo mostrou-se como uma alternativa para conservação do sêmen suíno a 10 °C, assim como o LPD. Além disso, esses mesmos diluentes constituem alternativas para conservação a curto prazo a 17 °C.

The use of suitable extenders is important to artificial insemination success. Therefore, the objective of this study was to evaluate the efficiency of extenders at different temperatures. The following extenders were used: Beltsville Thawing Solution (BTS); TRIS (Tris-hidroximetil-aminometano - H2NC(CH2OH)3); TRIS + egg yolk (TGO), and skim powdered milk (SPM). Fifty ejaculates were analyzed regarding sperm vigor, motility, membrane functionality, and mitochondrial activity. The TGO and SPM extenders maintained the highest values for vigor and motility at 10 °C, in comparison to the other treatments (p<0.05). At 17 °C, these extenders showed better results of vigor and motility compared to the others, only until D1 (p<0.05). From D2, BTS proved to be the best extender to preserve these characteristics. A higher percentage of sperm with a functional membrane was observed for TGO at 10 °C, followed by SPM, BTS, and TRIS (p<0.05). At 17 °C, BTS maintained this characteristic, except for DO, which showed better results for TGO and SPM. Regarding the mitochondrial activity, higher values were observed at 10 °C for TGO on all days of analysis and D0 at a temperature of 17 °C. The extender TRIS + egg yolk was shown as an alternative for the conservation of swine semen at 10 °C, as well as the SPM. In addition, these same extenders are alternatives for short-term conservation at 17 °C.

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Tris(glycinato)chromium(III) monohydrate [Cr(C2H4NO2)3·H2O] crystals were grown through the slow solvent evaporation method. The crystals were studied by Fourier transform infrared (FTIR) and Raman spectroscopy at room temperature. The assignments of vibration modes were performed using the Density Functional Theory (DFT). Thermal analyses (TGA, DTA, and DSC), X-ray diffraction (XRD), and Raman were used to study the phase changes on the crystals under high- and low-temperature conditions. Temperature-dependent XRPD measurements were carried out in the interval of 473-12 K. Several changes were observed in the patterns, like the appearance of new peaks and the disappearance of peaks occurring within 373-393 K due to water loss. In addition, the Raman measurements were performed in the 423-10 K interval. Several changes on the inter and intramolecular vibration bands during the cooling, such as decreasing bands' intensities, the appearance of vibration modes, and discontinuities on the modes' behavior, were observed. These spectral modifications occurred at about 370 K and within 120-220 K, thus, confirming that the crystals undergo two phase changes, one being structural and the other one conformational, respectively, at high- temperature and low-temperature conditions. Finally, thermal investigations corroborated the structural and vibrational results under high temperatures.

RESUMO

The medicinal uses of Calotropis procera are diverse, yet some of them are based on effects that still lack scientific support. Control of diabetes is one of them. Recently, latex proteins from C. procera latex (LP) have been shown to promote in vivo glycemic control by the inhibition of hepatic glucose production via AMP-activated protein kinase (AMPK). Glycemic control has been attributed to an isolated fraction of LP (CpPII), which is composed of cysteine peptidases (95%) and osmotin (5%) isoforms. Those proteins are extensively characterized in terms of chemistry, biochemistry and structural aspects. Furthermore, we evaluated some aspects of the mitochondrial function and cellular mechanisms involved in CpPII activity. The effect of CpPII on glycemic control was evaluated in fasting mice by glycemic curve and glucose and pyruvate tolerance tests. HepG2 cells was treated with CpPII, and cell viability, oxygen consumption, PPAR activity, production of lactate and reactive oxygen species, mitochondrial density and protein and gene expression were analyzed. CpPII reduced fasting glycemia, improved glucose tolerance and inhibited hepatic glucose production in control animals. Additionally, CpPII increased the consumption of ATP-linked oxygen and mitochondrial uncoupling, reduced lactate concentration, increased protein expression of mitochondrial complexes I, III and V, and activity of peroxisome-proliferator-responsive elements (PPRE), reduced the presence of reactive oxygen species (ROS) and increased mitochondrial density in HepG2 cells by activation of AMPK/PPAR. Our findings strongly support the medicinal use of the plant and suggest that CpPII is a potential therapy for prevention and/or treatment of type-2 diabetes. A common epitope sequence shared among the proteases and osmotin is possibly the responsible for the beneficial effects of CpPII.

RESUMO

Mycobacterium tuberculosis is the major etiological agent for tuberculosis (TB), which is the leading cause of single pathogen infection-related deaths worldwide. The End TB Strategy of the World Health Organization aimed to decrease the incidence of TB by 20% between 2015 and 2020, which was not achieved. Here, the growth-inhibitory effects of tris-(1,10-phenanthroline) iron (II) complex ([Fe(phen)3]2+), a known commercially available cheap chemical substance, were examined. The best in vitro results showed great activity with MIC ranging from 0.77 to 3.06 µM against clinical strains and at low pH (mimicking the granuloma) with MIC of 0.21 µM. Preliminary safety analysis revealed that the complex did not exhibit cytotoxic activity against different cell lines or mutagenic activity in vitro. The complex was orally bioavailable after 2 h of administration in vivo. Additionally, the results of the acute toxicity test revealed that the complex did not exert toxic effects in female BALB/c mice. The mechanism of action was performed using D29 mycobacteriophages where the treatment with different concentrations of the complex inhibited viral protein synthesis, which indicated that the anti-TB mechanisms of the complex involve protein synthesis inhibition. These findings suggested that [Fe(phen)3]2+ is a potential novel therapeutic for TB.

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In this study, we report the first isolation of three antibiotic indole alkaloid compounds from a Pseudomonad bacterium, Pseudomonas aeruginosa UWI-1. The bacterium was batch fermented in a modified Luria Broth medium and compounds were solvent extracted and isolated by bioassay-guided fractionation. The three compounds were identified as (1) tris(1H-indol-3-yl) methylium, (2) bis(indol-3-yl) phenylmethane, and (3) indolo (2, 1b) quinazoline-6, 12 dione. A combination of 1D and 2D NMR, high-resolution mass spectrometry data and comparison from related data from the literature was used to determine the chemical structures of the compounds. Compounds 1-3 were evaluated in vitro for their antimicrobial activities against a wide range of microorganisms using the broth microdilution technique. Compounds 1 and 2 displayed antibacterial activity against only Gram-positive pathogens, although 1 had significantly lower minimum inhibitory concentration (MIC) values than 2. Compound 3 displayed potent broad-spectrum antimicrobial activity against a range of Gram positive and negative bacteria. Several genes identified from the genome of P. aeruginosa UWI-1 were postulated to contribute to the biosynthesis of these compounds and we attempted to outline a possible route for bacterial synthesis. This study demonstrated the extended metabolic capability of Pseudomonas aeruginosa in synthesizing new chemotypes of bioactive compounds.

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In this work, the use of different solvents and temperatures was explored, aiming to evaluate their influence on the enantioseparation of pesticides by HPLC in polar-organic conditions, employing a column containing immobilized amylose tris(3-chloro-5-methylphenyl-carbamate). The chiral separation of seventeen different pesticides widely used as herbicides, fungicides, insecticides and precursors were studied. The mobile phases included methanol, ethanol, iso-propanol, n-propanol and acetonitrile; either pure or containing additives such as diethylamine, trifluoroacetic acid, formic acid, acetic acid or mixtures thereof. We studied the influence of these eluents on chiral separation of those pesticides in terms of retention factor, enantioselectivity, enantioresolution and peak symmetry. Regarding temperature influence, evaluated within the range 5 - 40 °C, nearly all the compounds decreased their retention and selectivity factors with the increase in temperature, although the effect was dependent on the mobile phase solvent. Moreover, estimation of thermodynamic parameters was performed based on linear van´t Hoff plots.

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Passiflora setacea is a wild species of passion fruit with interesting functional properties. Fruit seasonality demands conservation methods to enable its consumption throughout the year. We evaluated High Temperature Short Time (HTST) and Low Temperature Long Time (LTLT) binomials on physical, chemical, antioxidant and sensory characteristics of Passiflora setacea pulps. In natura (IN) and pasteurized pulps were analysed for DPPH, FRAP, ORAC, total phenolic content (TPC), vitamin C, bioactive amines, flavonoids, color, remaining enzymatic activity (REA), microbiological analyzes, sensory evaluation and physical stability. All binomials reached microbiological standards. Binomials 82 °C/20 s and 82 °C/40 s were selected for providing higher total antioxidant activity (TAA), TPC and lower REA. The highest levels of antioxidant activity, flavonoids, vitamin C were kept by 82 °C/20 s, without difference from IN pulp. LTLT binomial showed higher retention of bioactive amines, but also higher REA. Sensory acceptance was not affected by the binomials but pasteurized-cooked flavor was more checked for 82 °C 40 s than IN pulp.

RESUMO

In this work, we have studied both experimentally and theoretically the praziquantel (PZQ) chiral discrimination. According to the main results, the enantioseparation of PZQ was efficiently optimized by HPLC on the reverse phase from the Chiralpak IB column, which has cellulose tris (3,5-dimethylphenylcarbamate) (CDMPC) as a chiral selector. The thermodynamic and structural parameters obtained via density functional theory (DFT) calculations pointed out the chiral discrimination as well as the enantiomeric elution order of PZQ, thus elucidating the experimental data and validating our proposed method. Finally, the hydrogen bonds and π-π stacking interactions played a key role in the discrimination between the PZQ diastereomeric complexes formed.

RESUMO

Due to the global decrease in jaguar population, conservation strategies are essential and the development of effective semen cryopreservation protocols would contribute to the formation of germplasm banks. Therefore, the objectives were to (1) evaluate the use of TRIS and ACP-117c extenders for jaguar semen freezing, (2) describe the ultrastructural changes in sperm after cryopreservation, and (3) evaluate the binding capacity of the thawed sperm. Eight ejaculates from five mature individuals were collected by electroejaculation, extended in TRIS or a coconut based-extender (ACP-117c), and frozen in liquid nitrogen. Samples were evaluated for sperm motility, vigor, membrane functionality, mitochondrial activity, morphology (using light microscopy, scanning electron microscopy - SEM and transmission electron microscopy - TEM), sperm kinetic parameters (by computerized analysis - CASA), and sperm binding capability using an egg yolk perivitelline membrane assay. Samples preserved in TRIS presented better post-thaw motility (46.0 ±â€¯7.7%) and membrane functionality (60.5 ±â€¯4.2%) and higher mitochondrial activity (21.5 ±â€¯3.7%) than those preserved in ACP-117c (20.9 ±â€¯5.4% motile sperm; 47.1 ±â€¯2.5% functional membrane; 11.8 ±â€¯1.7% mitochondrial activity). Regarding ultrastructural evaluations, SEM showed that both extenders were able to preserve the superficial membrane of the sperm, but TEM revealed the occurrence of nuclear electron lucent points, especially in samples extended in ACP-117c. Additionally, TRIS also provided a higher number of sperm bound to the perivitelline membrane (29.5 ±â€¯3.3%) in comparison to samples diluted in ACP-117c (18.6 ±â€¯1.5%). Overall, we suggest the use of a TRIS-based extender for cryopreservation of jaguar semen.

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RESUMO

Dinotefuran is a low-cost agrochemical considered a highly toxic product. In this sense, there is a need for its constant environmental, biological, and food control, aiming to ensure its use to humans as well as to preserve biodiversity and ecosystems. In the present work, we developed an experimental and theoretical method for dinotefuran chiral discrimination. According to the main results, the dinotefuran enantioselective separation was efficiently optimized by high-performance liquid chromatography evaluating the influence of different percentage compositions in the mobile phase to improve the resolution of the peaks in the chromatogram. The novelty of this work was the proposition of a reduced molecular model for the chiral selector amylose-Tris-(3,5-dimethylphenylcarbamate) polysaccharide that was able to adequately describe at the molecular level its interaction with the dinotefuran enantiomers. Besides, the thermodynamic and structural parameters obtained via density functional theory calculations pointed out the chiral discrimination as well as the enantiomeric elution order of the analyte studied, confirming the experimental data, thus validating our proposed method. Finally, hydrogen bonds and repulsive interactions played a key role in the discrimination between the diastereomeric complexes, and consequently, for the dinotefuran enantioselective separation.

RESUMO

This study aimed to determine the effects of resveratrol in the trisaminomethane (TRIS)-egg yolk extender and its optimal inclusion level for goat semen cryopreservation. Five ejaculates of three Anglo Nubian goats were used, each divided into four 200 µL aliquots for use in four treatments: 0.00 (control), 0.04, 0.08 and 0.12 mg mL-¹ resveratrol in the TRIS-egg yolk extender. We evaluated progressive sperm motility and sperm vigor post-dilution, post-cooling, and post thawing; membrane integrity (HOST); and acrosomal integrity and performed a slow thermoresistance test (STT). The data were submitted to a regression analysis at a 5% probability. There was no difference in progressive motility or sperm vigor in the post-dilution (89.5, 89.0, 88.7 and 88.3, and 4.9, 5.0, 4.9, and 4.9) or post-cooling (81.0, 82.0, 83.0, and 78.3; and 4.3, 4.3, 4.2, and 4.2) experiments (P > 0.05), or in the complementary acrosomal integrity test (42.0, 47.4, 42.2 and 38.2) (P > 0.05). However, the motility and vigor parameters decreased linearly in the post-thaw phase, as well as during the 2 hours of incubation on STT (P < 0.05). These factors increased quadratically when resveratrol was added to HOST, to an optimal level of 0.039 mg mL-¹ resveratrol for a plasma membrane integrity of 52.55% (P < 0.05). The inclusion of resveratrol was effective in maintaining sperm viability; in particular, it was effective in maintaining plasmatic membrane integrity during the cryopreservation process up to 0.039 mg mL-1, meaning that it could be an alternative to conventionally used seminal extenders in goats.

O objetivo deste estudo foi determinar os efeitos e o melhor nível de inclusão de resveratrol em meio diluidor TRIS gema de ovo para criopreservação de sêmen caprino. Foram utilizados cinco ejaculados de três bodes da raça Anglo Nubiana. Cada ejaculado foi dividido em quatro alíquotas de 200 µL, compondo quatro tratamentos: 0,00 (controle); 0,04; 0,08 e 0,12mg mL-¹ de resveratrol no diluidor TRIS gema de ovo. Foram avaliadas a motilidade espermática progressiva e o vigor espermático pós diluição, pós-resfriamento e pós-descongelamento; integridade de membrana (HOST); integridade acrossomal e teste de termorresistência lento (TTR). Os dados foram submetidos à análise de regressão a 5% de probabilidade. Não houve diferença para a motilidade progressiva e o vigor espermático, respectivamente, na pós-diluição (89,5; 89,0; 88,7 e 88,3) e (4,9; 5,0; 4,9 e 4,9) e pós-resfriamento (81,0; 82,0; 83,0 e 78,3) e (4,3; 4,3; 4,2 e 4,2) (P 0,05). No entanto, os parâmetros motilidade e vigor reduziram linearmente no pós-descongelamento, assim como durante as 2 horas de incubação no TTR (P < 0,05). Houve efeito quadrático com a inclusão de resveratrol para HOST, apresentando um nível ótimo de 0,039mg mL-¹ de resveratrol para integridade de membrana plasmática de 52,55% (P <0,05). A inclusão de resveratrol foi eficiente na manutenção da viabilidade espermática; em especial, foi eficiente na manutenção da integridade da membrana plasmática durante o processo de criopreservação até o nível de 0,039mg mL-¹, podendo ser uma alternativa na composição dos diluidores seminais de caprinos.

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RESUMO

This study aimed to determine the effects of resveratrol in the trisaminomethane (TRIS)-egg yolk extender and its optimal inclusion level for goat semen cryopreservation. Five ejaculates of three Anglo Nubian goats were used, each divided into four 200 µL aliquots for use in four treatments: 0.00 (control), 0.04, 0.08 and 0.12 mg mL-¹ resveratrol in the TRIS-egg yolk extender. We evaluated progressive sperm motility and sperm vigor post-dilution, post-cooling, and post thawing; membrane integrity (HOST); and acrosomal integrity and performed a slow thermoresistance test (STT). The data were submitted to a regression analysis at a 5% probability. There was no difference in progressive motility or sperm vigor in the post-dilution (89.5, 89.0, 88.7 and 88.3, and 4.9, 5.0, 4.9, and 4.9) or post-cooling (81.0, 82.0, 83.0, and 78.3; and 4.3, 4.3, 4.2, and 4.2) experiments (P > 0.05), or in the complementary acrosomal integrity test (42.0, 47.4, 42.2 and 38.2) (P > 0.05). However, the motility and vigor parameters decreased linearly in the post-thaw phase, as well as during the 2 hours of incubation on STT (P < 0.05). These factors increased quadratically when resveratrol was added to HOST, to an optimal level of 0.039 mg mL-¹ resveratrol for a plasma membrane integrity of 52.55% (P < 0.05). The inclusion of resveratrol was effective in maintaining sperm viability; in particular, it was effective in maintaining plasmatic membrane integrity during the cryopreservation process up to 0.039 mg mL-1, meaning that it could be an alternative to conventionally used seminal extenders in goats.(AU)

O objetivo deste estudo foi determinar os efeitos e o melhor nível de inclusão de resveratrol em meio diluidor TRIS gema de ovo para criopreservação de sêmen caprino. Foram utilizados cinco ejaculados de três bodes da raça Anglo Nubiana. Cada ejaculado foi dividido em quatro alíquotas de 200 µL, compondo quatro tratamentos: 0,00 (controle); 0,04; 0,08 e 0,12mg mL-¹ de resveratrol no diluidor TRIS gema de ovo. Foram avaliadas a motilidade espermática progressiva e o vigor espermático pós diluição, pós-resfriamento e pós-descongelamento; integridade de membrana (HOST); integridade acrossomal e teste de termorresistência lento (TTR). Os dados foram submetidos à análise de regressão a 5% de probabilidade. Não houve diferença para a motilidade progressiva e o vigor espermático, respectivamente, na pós-diluição (89,5; 89,0; 88,7 e 88,3) e (4,9; 5,0; 4,9 e 4,9) e pós-resfriamento (81,0; 82,0; 83,0 e 78,3) e (4,3; 4,3; 4,2 e 4,2) (P < 0,05), assim como para o teste complementar integridade acrossomal (42,0; 47,4; 42,2 e 38,2) (P > 0,05). No entanto, os parâmetros motilidade e vigor reduziram linearmente no pós-descongelamento, assim como durante as 2 horas de incubação no TTR (P < 0,05). Houve efeito quadrático com a inclusão de resveratrol para HOST, apresentando um nível ótimo de 0,039mg mL-¹ de resveratrol para integridade de membrana plasmática de 52,55% (P <0,05). A inclusão de resveratrol foi eficiente na manutenção da viabilidade espermática; em especial, foi eficiente na manutenção da integridade da membrana plasmática durante o processo de criopreservação até o nível de 0,039mg mL-¹, podendo ser uma alternativa na composição dos diluidores seminais de caprinos.(AU)

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6-Triazolylmethyl-pyrrolo[3,4-b]pyridin-5-one tris-heterocycles were synthesized in 43-57% overall yields. The two-stage synthesis involved a cascade process (Ugi-3CR/aza Diels-Alder/N-acylation/aromatization) followed by a copper-assisted alkyne-azide [3+2] cycloaddition (CuAAC). This efficient and convergent strategy proceeded via complex terminal alkynes functionalized with a fused bis-heterocycle at the α-position. The final products are ideal candidates for SAR studies as they possess two privileged scaffolds in medicinal chemistry: 4-substituted or 1,4-substituted 1H-1,2,3-triazoles and pyrrolo[3,4-b]pyridin-5-ones.

RESUMO

In this study, Schiff bases of chitosan (CS) were synthesized using citronellal, citral, and their derivatives containing selenium and sulfur. Organoselenium and organosulfur compounds show attractive biological and pharmaceutical activities, which can be beneficial to CS-based materials. From the characterization analyses, it was found that the CS-derivatives containing organoselenium and organosulfur compounds exhibited the highest conversion degrees (23 and 28%). Biological assays were conducted using films prepared by the blending of CS-derivatives and poly(vinyl alcohol). The antimicrobial evaluation indicated that the film prepared with the sulfur-containing CS was the most active against the tested pathogens (Escherichia coli, Staphylococcus aureus, and Candida albicans) since it reduced considerably their counts (42.5%, 17.4%, and 18.7%). Finally, in vivo assays revealed that this film attenuates atopic dermatitis-like symptoms in mice by suppressing the increase of myeloperoxidase (MPO) activity and reactive species (RS) levels induced by 2,4-dinitrochlorobenzene (DNCB). In summary, CS-derivatives containing chalcogens, mainly organosulfur, are potential candidates for biomedical applications such as for the treatment of chronic skin diseases.

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A series of giant tris(heteroaryl)methanes are easily assembled by one-pot three-component synthesis by simple reflux in ethanol without catalyst or additives. Diversely substituted indoles (Ar1) react with quinoline aldehydes, quinolone aldehydes, chromone aldehydes, and fluorene aldehydes (Ar2CHO) and coumarins (Ar3) in 1:1:1 ratio to form the corresponding tris(heteroaryl)methanes (Ar1Ar2Ar3)CH along with (Ar1Ar1Ar2)CH triads. A series of new 2:1 triads were also synthesized by coupling substituted indoles with Ar2CHO. The coupling reactions could also be carried out in water (at circa 80 °C) but with chemoselectivity favoring (Ar1Ar1Ar2)CH over (Ar1Ar2Ar3)CH. The molecular structure of a representative (Ar1Ar2Ar3)CH triad was confirmed by X-ray analysis. Model tris(heteroaryl/aryl)methylium salts were generated by reaction with DDQ/HPF6 and studied by NMR and by DFT and GIAO-DFT.

RESUMO

BACKGROUND: The common marmoset (Callithrix jacchus) is one of the most studied Neotropical primates regarding reproduction. However, little has been reported on the black-tufted-ear marmoset (Callithrix penicillata), which may produce fertile hybrids with other Callithrix. This is the first study to evaluate sperm freezing from black-tufted-ear marmoset. METHODS: Testicles from all animals were measured, and semen was collected by penile vibrostimulation. Samples were analyzed after collection, after chilling and addition of glycerol, and after thawing. RESULTS AND CONCLUSIONS: Fresh semen from both species was similar in many aspects. Additionally, there is a relationship between total motility, plasma membrane integrity, and acrosome integrity observed in sperm samples from both species. We managed to evaluate fresh and thawed sperm with suitable methods for use under zoo or field conditions. However, TEST egg yolk with glycerol at 4% and 6% concentration was not effective for sperm protection in both species during cryopreservation.

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RESUMO

O objetivo deste trabalho foi avaliar a relação entre a concentração de proteínas no plasma seminal ovino com parâmetros de qualidade do sêmen criopreservado em diluentes TRIS e em Água de Coco em Pó (ACP102c). Um total de 12 coletas/animal em ovinos Santa Inês (n=2) e Dorper (n=2) foram realizadas para obtenção do plasma seminal e para criopreservação nos diluentes de trabalho. Foi utilizado o método de Bradford para determinação da concentração de proteína. Para avaliação do sêmen fresco e criopreservado foram utilizados os testes de viabilidade por eosina-nigrosina e teste hiposmótico (HOST), além dos parâmetros de motilidade em sistema de análise de sêmen auxiliada por computador (CASA). Baseado no valor médio da concentração de proteína, os ejaculados foram agrupados em alta (AP) e baixa (BP) concentração proteica. Correlações significativamente positivas foram encontradas entre a concentração de proteína com os parâmetros motilidade progressiva (PROG) e congelabilidade (CONGEL), e negativa para deslocamento lateral de cabeça (ALH) nas amostras criopreservadas em ambos os diluentes, além de correlação positiva para motilidade total (MOT) em TRIS. Sêmen de ejaculados do grupo AP criopreservados em TRIS apresentaram MOT, PROG e CONGEL significativamente superior ao grupo BP e inferiores para ALH. Quando criopreservado em ACP102c, sêmen do grupo AP foi superior ao BP para PROG e CONGEL. Variações na qualidade do sêmen criopreservado entre ejaculados podem estar associados à concentração de proteínas do plasma seminal, e estas podem atuar na manutenção da progressividade de espermatozoides ovinos criopreservados em diluentes TRIS e ACP102c.

The objective of this study was to evaluate the relation between the protein concentration in ram seminal plasma and quality parameters of the semen cryopreserved in TRIS and Coconut Water Powder (ACP102c) extenders. A total of 12 semen collections/animal of Santa Ines (n=2) and Dorper (n=2) rams were performed to obtain seminal plasma and semen cryopreservation in work extenders. The protein content was determined using the Bradford ́s method. The eosin-nigrosin and hyposmotic (HOST) viable tests and motility parameters obtained by computer assisted semen analysis were evaluated for fresh and cryopreserved semen. The ejaculates were grouped in high (AP) and low (BP) protein content, based on the mean value of protein concentration. Significantly positive correlations were found between the protein content and progressive motility (PROG), freezability (CONGEL) and negative for lateral head displacement (ALH) in the semen cryopreserved in both extenders. Therefore, positive correlation was found for total motility (MOT) in TRIS. Semen samples from AP group cryopreserved in TRIS extender were significantly better than BP group for MOT, PROG and CONGEL, and inferior for ALH. When criopreserved in ACP102c extender, the AP group were better than BP group for PROG and CONGEL. Variations in the quality of cryopreserved semen from different ejaculates may be associated with the concentration of seminal plasma proteins and may act to maintain the progressiveness of ram sperm cryopreserved in TRIS and ACP102c extenders.

Assuntos