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Leishmaniasis is a complex disease caused by infection with different Leishmania parasites. The number of medications used for its treatment is still limited and the discovery of new drugs is a valuable approach. In this context, here we describe the in vitro leishmanicidal activity and the in silico interaction between trypanothione reductase (TryR) and (-)-5-demethoxygrandisin B from the leaves of Virola surinamensis (Rol.) Warb. The compound (-)-5-demethoxygrandisin B was isolated from V. surinamensis leaves, a plant found in the Brazilian Amazon, and it was characterized as (7R,8S,7'R,8'S)-3,4,5,3',4'-pentamethoxy-7,7'-epoxylignan. In vitro antileishmanial activity was examined against Leishmania amazonensis, covering both promastigote and intracellular amastigote phases. Cytotoxicity and nitrite production were gauged using BALB/c peritoneal macrophages. Moreover, transmission electron microscopy was applied to probe ultrastructural alterations, and flow cytometry assessed the shifts in the mitochondrial membrane potential. In silico methods such as molecular docking and molecular dynamics assessed the interaction between the most stable configuration of (-)-5-demethoxygrandisin B and TryR from L. infantum (PDB ID 2JK6). As a result, the (-)-5-demethoxygrandisin B was active against promastigote (IC50 7.0 µM) and intracellular amastigote (IC50 26.04 µM) forms of L. amazonensis, with acceptable selectivity indexes. (-)-5-demethoxygrandisin B caused ultrastructural changes in promastigotes, including mitochondrial swelling, altered kDNA patterns, vacuoles, vesicular structures, autophagosomes, and enlarged flagellar pockets. It reduced the mitochondria membrane potential and formed bonds with important residues in the TryR enzyme. The molecular dynamics simulations showed stability and favorable interaction with TryR. The compound targets L. amazonensis mitochondria via TryR enzyme inhibition.
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Biotransformations are reactions mediated by microorganisms, such as fungi. These bioreactions have high chemo- and stereoselectivity on organic substrates and can be applied in the search for new bioactive compounds. In this study, acanthoic acid (AA) was biotransformed using the fungus Xylaria sp., giving the novel compound 3ß,7ß-dihydroxyacanthoic acid (S1). Both the AA and the product S1 were tested against Gram-positive and Gram-negative bacteria. To identify and validate possible biological targets as enzymes or proteins involved in the activity observed in vitro, we used the molecular docking method. Hydroxylation at the C-3 and C-7 positions of the biotransformation product enhanced its activity against Escherichia coli as well as its binding affinity and interactions with superoxide dismutase 1 (SOD1; PDB ID 4A7G). Based on our results, the SOD1 enzyme was suggested to be a possible target for the antioxidant activity of product S1.
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Gastric cancer is among the major causes of death from neoplasia leading causes of death worldwide, with high incidence rates and problems related to its treatment. Here, we outline how Geissospermum sericeum exerts antitumor activity on the ACP02 cell line (human gastric adenocarcinoma) and the mechanism of cell death. The ethanol extract and fractions, neutral fraction and alkaloid fraction, were characterized by thin-layer chromatography and HPLC-DAD, yielding an alkaloid (geissoschizoline N4-methylchlorine) identified by NMR. The cytotoxicity activity of the samples (ethanol extract, neutral fraction, alkaloid fraction, and geissoschizoline N4-methylchlorine) in HepG2 and VERO cells was determined by MTT. The ACP02 cell line was used to assess the anticancer potential. Cell death was quantified with the fluorescent dyes Hoechst 33342, propidium iodide, and fluorescein diacetate. The geissoschizoline N4-methylchlorine was evaluated in silico against caspase 3 and 8. In the antitumor evaluation, there was observed a more significant inhibitory effect of the alkaloid fraction (IC50 18.29 µg/mL) and the geissoschizoline N4-methylchlorine (IC50 12.06 µg/mL). However, geissoschizoline N4-methylchlorine showed lower cytotoxicity in the VERO (CC50 476.0 µg/mL) and HepG2 (CC50 503.5 µg/mL) cell lines, with high selectivity against ACP02 cells (SI 39.47 and 41.75, respectively). The alkaloid fraction showed more significant apoptosis and necrosis in 24 h and 48 h, with increased necrosis in higher concentrations and increased exposure time. For the alkaloid, apoptosis and necrosis were concentration- and time-dependent, with a lower necrosis rate. Molecular modeling studies demonstrated that geissoschizoline N4-methylchlorine could occupy the active site of caspases 3 and 8 energetically favorably. The results showed that fractionation contributed to the activity with pronounced selectivity for ACP02 cells, and geissoschizoline N4-methylchlor is a promising candidate for caspase inhibitors of apoptosis in gastric cancer. Thus, this study provides a scientific basis for the biological functions of Geissospermum sericeum, as well as demonstrates the potential of the geissoschizoline N4-methylchlorine in the treatment of gastric cancer.
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Historically, Mexico has had an important role in primate conservation research, however, studies have rarely included the human dimensions of primatology. Inclusion of these disciplines should be a priority, considering that human activities are responsible for the current socio-ecological crisis. Mexico is habitat for three primate species, and all are threatened. This urgency demands new approaches and broader perspectives. First, we propose three main research frameworks relevant for conducting PCEPs in Latin America: Participatory Action Research, Arts-based education in PCEPs and Knowledge Coproduction. Furthermore, we aimed to (1) describe a case study about primate conservation education in Southern Mexico based on participatory visual methods under the umbrella of Participatory Action Research (PAR), and (2) to conduct a self-reflective, critical, straightforward, and constructive analysis of the experience. We discuss the various challenges faced during the process (e.g., traditional teaching prevalence at schools, teachers that are not school-based, time and academic constraints). Additionally, we highlight some PAR aspects applicable for researchers and practitioners interested to go further than knowledge transmission (e.g., codesign, arts-based education, placed-based education, critical thinking, and capacity building). To collectively progress in primate conservation education in Mexico and other Latin American countries, projects could greatly benefit from context-specific, people-centered approaches, such as PAR. We encourage researchers to share more of their personal research experiences including both their successes and failures.
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Pesquisa sobre Serviços de Saúde , Primatas , Humanos , Animais , México , EcossistemaRESUMO
The present work reports the isolation and biological evaluation of three dimeric xanthones from Paecilomyces sp. EJC01.1 isolated as endophytic from Schnella splendens, a typical plant of the Amazon. The compounds phomoxanthone A (1), phomoxanthone B (2) and dicerandrol B (3) were isolated by chromatographic procedures and identified by spectroscopic methods of 1D and 2D NMR and MS. The extracts and compound 1 showed antimicrobial activities against Bacillus subtilis, Escherichia coli, Staphylococcus aureus, Salmonella typhimurium and Pseudomonas aeruginosa. The compound phomoxanthone A (1) showed greater inhibitory activity against B. subtilis (MIC of 7.81 µg mL-1); in addition, it also pronounced inhibitory effect against promastigote forms of Leishmania amazonensis (IC50 of 16.38 ± 1.079 µg mL-1) and epimastigote forms Trypanosoma cruzi (IC50 of 28.61 ± 1.071 µg mL-1). To provide more information about the antibacterial activity of compound 1, an unprecedented molecular docking study was performed using S-ribosyl-homocysteine lyase (LuxS) (PDB ID 2FQO), which showed a possible interaction of phomoxanthone A with two of the residues (His58 and Cys126) that are fundamental for the catalysis mechanism in B. subtilis, which may be associated with the higher activity, when compared to other bacteria, observed in experimental studies. Additionally, quantum studies (DFT) were performed, for which a low gap value (5.982 eV) was observed, which corroborates the reactivity of phomoxanthone A. Thus, phomoxanthone A can be a good agent against pathogenic bacteria.
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Leishmaniasis represents a serious world health problem, with 1 billion people being exposed to infection and a broad spectrum of clinical manifestations with a potentially fatal outcome. Based on the limitations observed in the treatment of leishmaniasis, such as high cost, significant adverse effects, and the potential for drug resistance, the aim of the present study was to evaluate the leishmanicidal activity of the compounds pseurotin A and monomethylsulochrin isolated from the biomass extract of Aspergillus sp. The chromatographic profiles of the extract were determined by high-performance liquid chromatography coupled with a diode-array UV-Vis detector (HPLC-DAD-UV), and the molecular identification of the pseurotin A and monomethylsulochrin were carried out by electrospray ionization mass spectrometry in tandem (LC-ESI-MS-MS) and nuclear magnetic resonance (NMR). Antileishmanial activity was assayed against promastigote and intracellular amastigote of Leishmania amazonensis. As a control, cytotoxicity assays were performed in non-infected BALB/c peritoneal macrophages. Ultrastructural alterations in parasites were evaluated by transmission electron microscopy. Changes in mitochondrial membrane potential were determined by flow cytometry. Only monomethylsulochrin inhibited the promastigote growth (IC50 18.04 ± 1.11 µM), with cytotoxicity to peritoneal macrophages (CC50 5.09 91.63 ± 1.28 µM). Activity against intracellular amastigote forms (IC50 5.09 ± 1.06 µM) revealed an increase in antileishmanial activity when compared with promastigotes. In addition to a statistically significant reduction in the evaluated infection parameters, monomethylsulochrin altered the ultrastructure of the promastigote forms with atypical vacuoles, electron-dense corpuscles in the cytoplasm, changes at the mitochondria outer membrane and abnormal disposition around the kinetoplast. It was showed that monomethylsulochrin leads to a decrease in the mitochondrial membrane potential (25.9%, p = 0.0286). Molecular modeling studies revealed that monomethylsulochrin can act as inhibitor of sterol 14-alpha-demethylase (CYP51), a therapeutic target for human trypanosomiasis and leishmaniasis. Assessed for its drug likeness, monomethylsulochrin follows the Lipinski Rule of five and Ghose, Veber, Egan, and Muegge criteria. Furthermore, monomethylsulochrin can be used as a reference in the development of novel and therapeutically useful antileishmanial agents.
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Antiprotozoários , Leishmania mexicana , Leishmania , Leishmaniose , Animais , Antiprotozoários/química , Aspergillus , Biomassa , Humanos , Leishmaniose/tratamento farmacológico , Camundongos , Camundongos Endogâmicos BALB C , Simulação de Acoplamento Molecular , Extratos Vegetais/farmacologiaRESUMO
Carajurin is the main constituent of Arrabidaea chica species with reported anti-Leishmania activity. However, its mechanism of action has not been described. This study investigated the mechanisms of action of carajurin against promastigote forms of Leishmania amazonensis. Carajurin was effective against promastigotes with IC50 of 7.96 ± 1.23 µg.mL-1 (26.4 µM), and the cytotoxic concentration for peritoneal macrophages was 258.2 ± 1.20 µg.mL-1 (856.9 µM) after 24 h of treatment. Ultrastructural evaluation highlighted pronounced swelling of the kinetoplast with loss of electron-density in L. amazonensis promastigotes induced by carajurin treatment. It was observed that carajurin leads to a decrease in the mitochondrial membrane potential (p = 0.0286), an increase in reactive oxygen species production (p = 0.0286), and cell death by late apoptosis (p = 0.0095) in parasites. Pretreatment with the antioxidant NAC prevented ROS production and significantly reduced carajurin-induced cell death. The electrochemical and density functional theory (DFT) data contributed to support the molecular mechanism of action of carajurin associated with the ROS generation, for which it is possible to observe a correlation between the LUMO energy and the electroactivity of carajurin in the presence of molecular oxygen. All these results suggest that carajurin targets the mitochondria in L. amazonensis. In addition, when assessed for its drug-likeness, carajurin follows Lipinski''s rule of five, and the Ghose, Veber, Egan, and Muegge criteria.
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Acknowledging the need of identifying new compounds for the treatment of leishmaniasis, this study aimed to evaluate, from in vitro trials, the activity of flavones from Arrabidaea chica against L. amazonensis. The chromatographic profiles of the hydroethanolic extract and a flavone-rich fraction (ACFF) from A. chica were determined by high-performance liquid chromatography coupled with a diode-array UV-Vis detector (HPLC-DAD-UV) and electrospray ionization mass spectrometry in tandem (LC-ESI-MS-MS). The flavones luteolin (1) and apigenin (2), isolated from chromatographic techniques and identified by Nuclear Magnetic Resonance of 1H and 13C, were also quantified in ACFF, showing 190.7 mg/g and apigenin 12.4 mg/g, respectively. The other flavones were identified by comparing their spectroscopic data with those of the literature. The in vitro activity was assayed against promastigotes and intramacrophagic amastigote forms of L. amazonensis. Cytotoxicity tests were performed with peritoneal macrophages of BALB/c mice. Nitrite quantification was performed with Griess reagent. Ultrastructural investigations were obtained by transmission electron microscopy. Anti-Leishmania assays indicated that the IC50 values for ACFF, apigenin, and luteolin were obtained at 40.42 ± 0.10 and 31.51 ± 1.13 µg/mL against promastigotes, respectively. ACFF and luteolin have concentration-dependent cytotoxicity. ACFF and luteolin also inhibited the intra-macrophagic parasite (IC50 3.575 ± 1.13 and 11.78 ± 1.24 µg/mL, respectively), with a selectivity index of 11.44 for ACFF. Promastigotes exposed to ACFF and luteolin exhibited ultrastructural changes, such as intense cytoplasm vacuolization and mitochondrial swelling. These findings data evidence the antileishmanial action of flavone-rich fractions of A. chica against L. amazonensis, encouraging further studies.
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The natural compound ravenelin was isolated from the biomass extracts of Exserohilum rostratum fungus, and its antimicrobial, antiplasmodial, and trypanocidal activities were evaluated. Ravenelin was isolated by column chromatography and HPLC and identified by NMR and MS. The susceptibility of Gram-positive and Gram-negative bacteria strains to ravenelin was determined by microbroth dilution assay. Cytotoxicity was evaluated in hepatocarcinoma cells (HepG2) and BALB/c peritoneal macrophages by using MTT. SYBR Green I-based assay was used in the asexual stages of Plasmodium falciparum. Trypanocidal activity was tested against the epimastigote and intracellular amastigote forms of Trypanosoma cruzi. Ravenelin was active against Gram-positive bacteria strains, with emphasis on Bacillus subtilis (MIC value of 7.5 µM). Ravenelin's antiparasitic activities were assessed against both the epimastigote (IC50 value of 5 ± 1 µM) and the intracellular amastigote forms of T. cruzi (IC50 value of 9 ± 2 µM), as well as against P. falciparum (IC50 value of 3.4 ± 0.4 µM). Ravenelin showed low cytotoxic effects on both HepG2 (CC50 > 50 µM) and peritoneal macrophage (CC50 = 185 ± 1 µM) cells with attractive selectivity for the parasites (SI values > 15). These findings indicate that ravenelin is a natural compound with both antibacterial and antiparasitic activities, and considerable selectivity indexes. Therefore, ravenelin is an attractive candidate for hit-to-lead development.
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Antibacterianos/farmacologia , Antiprotozoários/farmacologia , Ascomicetos/química , Macrófagos Peritoneais/citologia , Xantonas/farmacologia , Animais , Antibacterianos/química , Antiprotozoários/química , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Biomassa , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Células Hep G2 , Humanos , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/parasitologia , Espectroscopia de Ressonância Magnética , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Estrutura Molecular , Plasmodium falciparum/efeitos dos fármacos , Trypanosoma cruzi/efeitos dos fármacos , Xantonas/químicaRESUMO
Syzygium aromaticum has a diversity of biological activities due to the chemical compounds found in its plant products such as total phenolic compounds and flavonoids. The present work describes the chemical analysis and antimicrobial, antioxidant, and antitrypanosomal activity of the essential oil of S. aromaticum. Eugenol (53.23%) as the major compound was verified by gas chromatography-mass spectrometry. S. aromaticum essential oil was more effective against S. aureus (MIC 50 µg/mL) than eugenol (MIC 250 µg/mL). Eugenol presented higher antioxidant activity than S. aromaticum essential oil, with an EC50 of 12.66 and 78.98 µg/mL, respectively. S. aromaticum essential oil and eugenol exhibited Trypanosoma cruzi inhibitory activity, with IC50 of 28.68 ± 1.073 and 31.97 ± 1.061 µg/mL against epimastigotes and IC50 of 64.51 ± 1.658 and 45.73 ± 1.252 µg/mL against intracellular amastigotes, respectively. Both compounds presented low cytotoxicity, with S. aromaticum essential oil displaying 15.5-fold greater selectivity for the parasite than the cells. Nitrite levels in T. cruzi-stimulated cells were reduced by essential oil (47.01%; p = 0.002) and eugenol (48.05%; p = 0.003) treatment. The trypanocidal activity of S. aromaticum essential oil showed that it is reasonable to use it in future research in the search for new therapeutic alternatives for trypanosomiasis.
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Arrabidaea chica Verlot (crajiru) is a plant used in folk medicine as an astringent, anti-inflammatory, wound healing and to treat fungal and viral diseases such as measles chickenpox and herpes. Arrabidaea chica has several morphotypes recognized but little is known about its chemical variability. In the present study the anthocyanidin profile of A. chica morphotypes collected in two seasons (summer and winter) have been examined and their activity against Leishmania infection compared. High-performance liquid chromatography coupled to a diode-array detector (HPLC-DAD-UV) and by tandem mass spectrometry with electrospray ionization (ESI-MS/MS) were used for anthocyanidin separation and identification. Antileishmanial activity was measured against promastigote forms of Leishmania amazonensis. Multivariate analysis, principal component analysis (PCA) and Pearson's correlation were performed to classify morphotypes accordingly to their anthocyanidin profile. The presence of 6,7,3',4'-tetrahydroxy-5-methoxyflavylium (3'-hydroxy-carajurone) (1), carajurone (2), 6,7,3'-trihydroxy-5,4'-dimethoxy-flavylium (3'-hydroxy-carajurin) (3) and carajurin (4), and three unidentified anthocyanidins were detected. Two different groups were recognized: group I containing 3'-hydroxy-carajurone; and group II with high content of carajurin. Among anthocyanidins identified in the extracts, only carajurin showed significant statistical correlation (p = 0.030) with activity against L. amazonensis. Carajurin could thus be considered as a pharmacological marker for the antileishmanial potential of the species.
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Antocianinas/química , Antiprotozoários/farmacologia , Bignoniaceae/química , Leishmania mexicana/efeitos dos fármacos , Antocianinas/isolamento & purificação , Antocianinas/farmacologia , Antiprotozoários/química , Antiprotozoários/isolamento & purificação , Bignoniaceae/metabolismo , Cromatografia Líquida de Alta Pressão , Extratos Vegetais/química , Análise de Componente Principal , Proantocianidinas/química , Proantocianidinas/isolamento & purificação , Proantocianidinas/farmacologia , Estações do Ano , Espectrofotometria , Espectrometria de Massas em TandemRESUMO
Resumen Este artículo es producto de una investigación de mixta donde predominó el énfasis en la descripción de los resultados, con características cuantitativas de la información obtenida a través del cuestionario aplicado. El diseño descriptivo permitió observar y reflexionar sobre las mediaciones pedagógicas que se dan en los contextos familiares frente a la recepción y consumo de productos y servicios ofertados por la televisión, internet y las redes sociales on line. Los participantes fueron estudiantes universitarios (16 y 24 años de edad) a los que se les aplicó un cuestionario y un diario de observación. Se realizó una triangulación de los resultados de la observación participante y de los cuestionarios aplicados. Se encontró que existía un tipo de mediación familiar frente a los contenidos televisivos. Sin embargo, no se encontró un indicador que aclare si las familias están mediando los contenidos que circulan en internet. Esto permite una oportunidad para plantear estrategias de comunicación familiar, que posibiliten una injerencia de los padres / cuidadores o acompañantes sobre estos contenidos, teniendo en cuenta el ciclo vital individual y familiar.
Abstract This article was based on a mixed methods research where the predominant emphasis was placed on the description of the results, with quantitative characteristics obtained through the applied questionnaire. The descriptive design made it possible to observe and reflect on the pedagogical mediations that occur in family contexts with regard to the reception and consumption of products and services offered by television, the internet, and online social networks. The participants were university students (16 and 24-year-old) who responded the questionnaire and kept an observational diary. A triangulation of the results of both the participants' observations and the questionnaires was used. We found that there is a type of family mediation with regard to television contents. However, no indicator was found to clarify if the families are mediating the contents and information circulating on the internet. This opens up an opportunity to propose family communication strategies that allow for a more direct influence of the parents/caregivers or companions on these contents, taking into account the individual and family life cycles.
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Aniba rosaeodora is one of the most widely used plants in the perfumery industry, being used as medicinal plant in the Brazilian Amazon. This work aimed to evaluate the chemical composition of A. rosaeodora essential oil and its biological activities. A. rosaeodora essential oil presented linalool (93.60%) as its major compound. The A. rosaeodora essential oil and linalool showed activity against all the bacteria strains tested, standard strains and marine environment bacteria, with the lower minimum inhibitory concentration being observed for S. aureus. An efficient antioxidant activity of A. rosaeodora essential oil and linalool (EC50: 15.46 and 6.78 µg/mL, respectively) was evidenced by the inhibition of the 2,2-azinobis- (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical. The antitrypanosomal activity of A. rosaeodora essential oil and linalool was observed at high concentrations against epimatigote forms (inhibitory concentration for 50% of parasites (IC50): 150.5 ± 1.08 and 198.6 ± 1.12 µg/mL, respectively), and even higher against intracellular amastigotes of T. cruzi (IC50: 911.6 ± 1.15 and 249.6 ± 1.18 µg/mL, respectively). Both A. rosaeodora essential oil and linalool did not exhibit a cytotoxic effect in BALB/c peritoneal macrophages, and both reduced nitrite levels in unstimulated cells revealing a potential effect in NO production. These data revealed the pharmacological potential of A. rosaeodora essential oil and linalool, encouraging further studies.
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PURPOSE OF REVIEW: This article reviewed very recent papers (2016) discussing or bringing clinical evidences of the possible common pathways leading to diabetic foot syndrome (DFS) and increased mortality rates. RECENT FINDINGS: Diabetic patients with diabetic foot syndrome have a mortality rate greater than twofold when compared with non-ulcerated diabetics. In addition, the 5-year mortality rate following amputation is estimated at 39-68%, a life expectancy comparable to aggressive types of cancer or advanced congestive heart failure. The majority of patients with diabetic foot ulcer also present insulin resistance, central obesity, dyslipidemia, and hypertension that characterize the metabolic syndrome that, in turn, is associated with an elevated risk of major cardiovascular events. Sensory neuropathy is the primary cause of more the 60% of diabetic foot ulcer. Diabetic peripheral neuropathy is a microvascular complication of diabetes mellitus and in type 2 diabetes, not only hyperglycemia but also other metabolic alterations and persistent inflammatory status due to adiposity play a major role in axon injury. Elevated triglycerides have been showed to be an independent risk factor for lower extremity amputation in diabetic patients. Also, toxic adiposity, oxidative stress, mitochondrial dysfunction, activation of the polyol pathway, accumulation of advanced glycation end products (AGEs), and elevation of inflammatory markers are also implicated in diabetic vascular disease and neuropathy. The hypotheses that the association between DFS and increased rates of mortality reflects the progression of micro- and macrovascular complications are reinforced by the additional association of DFU to renal failure and retinopathy.
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Doenças Cardiovasculares/mortalidade , Pé Diabético/mortalidade , Amputação Cirúrgica , Angiopatias Diabéticas/complicações , Angiopatias Diabéticas/mortalidade , Pé Diabético/etiologia , Pé Diabético/cirurgia , Neuropatias Diabéticas/complicações , Neuropatias Diabéticas/mortalidade , Progressão da Doença , Humanos , Fatores de RiscoRESUMO
Objetivo: Determinar si los cambios de temperatura afectan a la resistencia flexural de los acrílicos de termocurado para la base de dentaduras con y sin insertos metálicos Materiales y métodos: Se elaboraron 80 muestras de acrílico de termocurado marca Veracril® según la especificación Nº12 de la American Dental Association (ADA) (10×65×25 mm); se conformaron cuatro gru-pos de 20 probetas, organizándolas de la siguiente manera Grupo 1: muestras sin realizar termociclado y sin inserto metálico. Grupo 2: muestras sometidas a termociclado y sin inserto metálico. Grupo 3: muestras sin realizar termociclado y con inserto metálico. Grupo 4 muestras sometidas a termociclado y con inserto metálico. Se realizaron 1000 ciclos termales mediante un procedimiento manual de 2 minutos por cada ciclo térmico, correspondiendo 1 minuto en temperatura de 5 ± 2 oC y 1 minuto a 55 ± 2 oC a un ciclo. La resistencia flexural se evaluó con una prueba de tres puntos a una velocidad de 1mm/min. El análisis estadístico fue a través de la prueba t de Student para muestras relacionadas con un nivel de significancia del 5%. Resultados: La media de resistencia flexural fue de 73.51, 65.65, 71.14 y 73.08 Megapascales (MPa)., para los grupos 1,2,3 y 4 respectivamente. Se observó que el G1 fue mayor que el G2 (p=0.002) y el G3 con el G4 no obtuvo valores con diferencia estadística significativa (p=0.554). Conclusión: Los cambios térmicos como procesos de envejecimiento del material influyen de forma negativa en la resistencia flexural de las muestras que en su estructura no presentaban inserto metálico, mientras que las muestras que poseían los insertos mejoraron la resistencia del material siendo esto estadísticamente comprobable.
Objective: The aim of this study was to determine if the different temperature changes affect in the flexural strength of the heat-cured acrylic for the base of dentures with and without metallic inserts by means of thermal cycling and flexion tests.Ma-terials and Methods: Eightysamples were prepared of a heat-cure acrylic Veracril® marque according to the specification no. Nº12 de la American Dental Association (ADA) (10×65×25 mm); Four groups of 20 buretteswere formed, each being Group 1: samples without realizing thermo cycling and without metallic insert. Group 2 for samples submitted to thermo cycling and wi-thout metallic insert. Group 3 for samples without thermo cycling and metallic insert in this structure. Group 4 samples submitted to thermo cycling and with metallic insert.1000 thermal cycles were realized by means of a manual procedure of 2 minutes by every thermal cycle, corresponding 1 minute in temperature of 5 ± 2 oC and 1 minute to 55 ± 2 oC to a cycle. The flexural resis-tance was evaluated by a test of three points at a speed of 1mm/min.The statistical analysis was through the Student t-test with a level of significance of 5%.Results: The mean flexural resistance was 73.51, 65.65, 71.14 and 73.08 MPa. For the groups 1,2,3 and 4 respectively. It was observed that G1 was greater than G2 (p = 0.002) and G3 with G4 did not obtain values with significant statistical difference (p = 0.554). Conclusion: The thermal changes as aging processes of the material negatively influence the flexural resistance of the samples which in their structure did not have a metallic insert improving the resistance of the material.
Objetivo: Determinar se a mudança de temperatura afeta, à resistência de flexão dos acrílicos de termo curvos para a base de den-taduras com e sem inserções metálicas. Materiais e métodos: elaboraram 80 amostras de acrílico curvo marca Veracril® segundo a especificação Nº12 da American Dental Association (ADA) (10×65×25 mm); conformaram-se quatro grupos de 20 provetas, organizando da seguinte maneira Grupo 1: amostras sem realizar termo ciclagem e sem inserção metálica. Grupo 2: amostras submetidas a termo ciclagem e sem inserção metálica. Grupo 3: amostras sem realizar termo ciclagem e com inserção metálica. Grupo 4 amostras submetidas a termo ciclagem e com inserção metálica. Realizaram-se 1000 ciclos termais mediante um procedi-mento manual de 2 minutos em cada ciclo térmico, correspondendo 1 minuto em temperatura de 5 ± 2 C e 1 minuto a 55 ± 2 C a um ciclo. A resistência de flexão se avaliou com uma prova de três pontos a uma velocidade de 1mm/min. A análise estadística foi através da prova t de Student para amostras relacionadas com um nível de significância de 5%. Resultados: A média de resistência de flexão foi de 73.51, 65.65, 71.14 e 73.08 Megapascales (MPa)., para os grupos 1,2,3 e 4 respetivamente. Observou-se que o G1 foi maior que e o G2 (p=0.002) e o G3 com o G4 não teve valores com diferença estadística significante (p=0.554). Conclusão: As mudanças térmicas como processos de envelhecimento do material influência de forma negativa na resistência de flexão das amostras que na sua estrutura não apresentavam inserção metálica, enquanto que as amostras que possuíam as inserções melho-raram a resistência do material sendo isto estatisticamente comprovável.
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Prostodontia , Manejo de Espécimes , Resinas Acrílicas , Planejamento de Prótese Dentária , Prótese Dentária , Polimetil Metacrilato , Falha de Prótese , Ajuste de Prótese , Análise Diferencial Térmica , Má Oclusão , BocaAssuntos
Anti-Hipertensivos/administração & dosagem , Hipertensão/diagnóstico , Hipertensão/tratamento farmacológico , Adolescente , Distribuição por Idade , Pressão Sanguínea , Determinação da Pressão Arterial , Estatura , Brasil , Criança , Vias de Administração de Medicamentos , Esquema de Medicação , Feminino , Humanos , Hipertensão/etiologia , Masculino , Exame Físico , Distribuição por SexoRESUMO
El síndrome de Noonan es una enfermedad genética, poco conocida, producida por una mutación en el cromosoma 12q22. En Cuba existen pocos datos sobre esta afección, ya que no se han realizado estudios con una muestra significativa que demuestren la frecuencia real de la afección. Se presenta un paciente de ocho años de edad, natural de Banes, Holguín, al cual se le diagnosticó el síndrome a través de la técnica comparativa o de patrón, y considerando las características clínicas y radiológicas. Se tuvo en cuenta el consentimiento de los padres para realizar y divulgar este informe. El interés de este caso radica en la baja frecuencia de aparición del Síndrome de Noonan, de hecho, es el primero que se ha diagnosticado en el municipio.
Noonan’s syndrome is a genetic, little-known disease, produced for a mutation in the 12q22 chromosome. Few data on this affection exists in Cuba; since studies with a significant sample have not been conducted that demonstrate the real frequency of the affection. An eight year old patient’s case from Banes, Holguín, is presented, to whom the syndrome through comparative technique was diagnosed, and considering the clinics and radiological characteristics. The consent of parents to do and to divulge this report was taken into account. The interest of this case consists on the low frequency of appearing of Noonan’s syndrome, in fact, the first one that has been diagnosed at the municipality.
RESUMO
En este artículo se hace una revisión fundamentada en investigaciones a nivel local, nacional e internacional sobre los cambios que en la contemporaneidad han afectado la estructura familiar y han contribuido a nuevos tipos de familia. En este caso, el interés ha sido analizar las conclusiones de los investigadores sobre las familias monoparentales con hijos adolescentes encontrando diferencias en los resultados. Algunos investigadores señalan que este tipo de familia coloca en riesgo a los hijos adolescentes en temas de drogadicción, delincuencia; otros expresan que no se puede generalizar a todas las familias monoparentales, por esto es importante estudiar la función que desempeña el padre o la madre que lidera la familia, para favorecer el desarrollo psicológico de los hijos. Por lo anterior, se pretende estudiar en las familias monoparentales que se encuentran en la etapa vital de la adolescencia, su dinámica, especialmente los límites, reglas y comunicación interaccional como aspectos que organizan la convivencia en pro del desarrollo de sus integrantes, en especial de los adolescentes que están en la tarea vital de forjar su identidad.
This article reviews local, national and international research on the changes that have affected the contemporary family structure and have contributed to new types of family. In this case, interest has centered in know the conclusions of the researchers on single-parent families with teenagers because they have found differences in the outcomes. Some researchers point out that this type of family place the children at risk for substance abuse, crime, etc., while others say that cannot be generalized to all single- parent families. So it is important to study the role of the father leading the family, the role exerted to promote the psychological development of children. Thus we wish to study in single-parent families that are in the life stage of adolescence, its dynamics, especially limits, rules and interactional communication as aspects that organize coexistence favoring the development of its members especially teenagers in the vital task of forging their identity.
RESUMO
Neoplasias hemolinfáticas em cavalos são relativamente incomuns, porém o linfoma é o mais frequente, sendo relatado desdea fase neonatal a animais com idade avançada. O linfoma em cavalos é uma doença que apresenta diferenças entre indivíduosincluindo sinais clínicos, curso da doença, resultados laboratoriais e achados patológicos. Os sinais clínicos variam de acordocom a localização da neoplasia, porém os mais comuns são depressão, perda de peso progressiva e linfadenopatia, podem estarassociados com edema ventral, angústia respiratória, febre, anemia, cólica branda ou diarréia. Os linfomas são classificadosanatomicamente em generalizado ou multicêntrico, alimentar ou intestinal, mediastinal ou tímica e cutânea. Podem ocorrersíndromes paraneoplásicas e geralmente é realizada a eutanásia devido à debilidade em que o animal se encontra. Este estudo éum relato de caso sobre um cavalo macho encaminhado para o Setor de Grandes Animais do Hospital Veterinário da UniversidadeFederal do Paraná com histórico e sinais de pneumonia, anorexia e emagrecimento progressivo. Ao exame físico foram observadasalterações clínicas como taquicardia, taquipnéia, linfadenopatia de linfonodos submandibular e pré-escapulares e edema ventral;o perfil hematológico mostrou hiperfibrinogenemia, neutrofilia e linfopenia e a biópsia aspirativa dos linfonodos alterados não foiconclusiva, porém sugestivo a li