RESUMEN
OBJECTIVE: The objective of the study is to examine whether adolescents' road safety perception (RSP) acts as a mediator on the association between the distance from home to the nearest park and the use of the parks for physical activity (PA). STUDY DESIGN: This is a cross-sectional study. METHODS: The evaluation was through a random sample of 1130 adolescents (534 male), corresponding to 47.3%, 14-20 years old, from Porto Alegre, Brazil. RSP was assessed through some questions of the Neighborhood Environment Walkability Scale for Youth. Park use, socioeconomic status, age, and sex were measured using a questionnaire. Distance from home to the nearest park was evaluated through geographic information system. Data analysis was performed using Pearson correlation, and linear regression models were fitted as per the Baron and Kenny procedures for mediation analyses. All analyses were adjusted for sex and socioeconomic status. RESULTS: Road safety perception is independently associated with less distance from home to the nearest park (P = 0.04) and use of the parks for PA (P = 0.02). Road safety perception is a mediator and explains 16% of the association between park use and distance from home to the park (indirect Effect = -40.9966; 95% confidence interval [CI]: 119.3733-2.2455). CONCLUSION: Our findings indicated that RSP is a mediator on the association between the distance from home to the nearest park and the use of the parks for PA. Future studies should take this into consideration frequency and intensity of PA and other environmental characteristics, such as crime, aesthetics, and neighborhood facilities.
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Planificación Ambiental/estadística & datos numéricos , Ejercicio Físico , Parques Recreativos/estadística & datos numéricos , Percepción , Características de la Residencia/estadística & datos numéricos , Seguridad , Adolescente , Brasil , Estudios Transversales , Femenino , Sistemas de Información Geográfica , Humanos , Masculino , Encuestas y Cuestionarios , Adulto JovenRESUMEN
Zymomonas mobilis has long attracted attention owing to its capacity to ferment hexose to ethanol. From a taxonomic viewpoint, Z. mobilis is a unique species of the genus Zymomonas, separated into three subspecies, Z. mobilis subsp. mobilis, Z. mobilis subsp. pomaceae and Z. mobilis subsp. francensis on the basis of physiological tests, which are often unreliable owing to the genetic proximity among these species. Currently, the use of molecular techniques is more appropriate for identification of these bacterial subspecies. In this study, the 32 strains of Z. mobilis present in the UFPEDA bacterial collection were characterized using molecular techniques, such as sequencing of the 16S rDNA gene and its theoretical restriction profile, classifying them as members of the subspecies, Z. mobilis subsp. mobilis. In addition, anaerobic cultivations were performed, which showed the biological diversity of the strains in terms of growth, sugar consumption and ethanol production. From these results, it was possible to identify the strain Z-2-80 as a promising bacterium for use in the fermentation process. SIGNIFICANCE AND IMPACT OF THE STUDY: Zymomonas mobilis is a bacterium of great relevance to biotechnology, owing to its capacity to ferment hexose to ethanol. On a molecular basis, 32 isolates were identified as Z. mobilis subsp. mobilis. However, intraspecific diversity was identified when these were grown under strictly anaerobic conditions. The results obtained from this study suggest a strain of Z. mobilis as an alternative for use in the fermentation process.
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Reactores Biológicos/microbiología , ADN Bacteriano/genética , Etanol/metabolismo , Zymomonas/clasificación , Zymomonas/metabolismo , Anaerobiosis , Brasil , ADN Ribosómico/genética , Fermentación , Hexosas/metabolismo , ARN Ribosómico 16S/genética , Zymomonas/genética , Zymomonas/aislamiento & purificaciónRESUMEN
WHAT IS KNOWN AND OBJECTIVE: Thrombocytopenia, not associated with bone marrow primary disease, is a common clinical problem. The possibility of drug-induced thrombocytopenia must be considered, especially in hospitalized patients. Drugs can cause thrombocytopenia by several mechanisms including direct bone marrow or other organ toxicity, and immune reactions. CASE DESCRIPTION: We describe a patient presenting with thrombocytopenia likely related to bisoprolol. WHAT IS NEW AND CONCLUSION: We report a case of bisoprolol-induced thrombocytopenia which resolved with drug discontinuation and steroid therapy. We review the mechanisms involved in drug-induced immune thrombocytopenia.
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Antihipertensivos/efectos adversos , Bisoprolol/efectos adversos , Trombocitopenia/inducido químicamente , Humanos , Masculino , Persona de Mediana EdadRESUMEN
In this study, a recombinant chimeric protein (RCP), which was composed of specific CD4+ and CD8+ T-cell epitopes to murine and human haplotypes, was evaluated as an immunogen against Leishmania infantum infection in a murine model. BALB/c mice received saline were immunized with saponin or with RCP with or without an adjuvant. The results showed that RCP/saponin-vaccinated mice presented significantly higher levels of antileishmanial IFN-γ, IL-12 and GM-CSF before and after challenge, which were associated with the reduction of IL-4 and IL-10 mediated responses. These animals showed significant reductions in the parasite burden in all evaluated organs, when both limiting dilution and quantitative real-time PCR techniques were used. In addition, the protected animals presented higher levels of parasite-specific nitrite, as well as the presence of anti-Leishmania IgG2a isotype antibodies. In conclusion, the RCP/saponin vaccine could be considered as a prophylactic alternative to prevent against VL.
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Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Epítopos de Linfocito T/inmunología , Leishmania infantum , Vacunas contra la Leishmaniasis/inmunología , Leishmaniasis Visceral/prevención & control , Proteínas Recombinantes de Fusión/inmunología , Adyuvantes Inmunológicos/administración & dosificación , Animales , Femenino , Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Humanos , Inmunogenicidad Vacunal , Interleucina-10/metabolismo , Interleucina-12/metabolismo , Interleucina-4/metabolismo , Leishmania infantum/inmunología , Vacunas contra la Leishmaniasis/genética , Ratones , Ratones Endogámicos BALB C , Proteínas Recombinantes de Fusión/genética , Saponinas/inmunología , Vacunas Sintéticas/inmunologíaRESUMEN
Assemblages of roving herbivores were consistently different between eastern, warmer, sheltered sites and western, colder, more wave-exposed sites. At eastern sites, detritivorous-herbivorous species dominated while omnivores had the highest biomass and were dominant at western sites. Macroalgivores did not show any trends related to location. These distributional patterns, at relatively small spatial scales of a few kilometres, mirror large-scale latitudinal patterns observed for the studied species along the entire Brazilian coast, where cold water associated species are abundant on south-eastern rocky reefs (analogous to the western sites of this study), and tropical species are dominant on north-eastern coral reefs (analogous to the eastern sites). Species-level analyses demonstrated that depth was an important factor correlated with biomasses of Diplodus argenteus, Sparisoma axillare and Sparisoma tuiupiranga, probably due to resource availability and interspecific competition. Herbivorous fish assemblages in the study area have been historically affected by fishing, and combined with the variation in assemblage structure, this is likely to have important, spatially variable effects on the dynamics of benthic communities.
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Arrecifes de Coral , Peces , Herbivoria , Animales , Biomasa , BrasilRESUMEN
The formation of nurse cells in host muscle cells during Trichinella spiralis infection is a key step in the infective mechanism. Collagen trimerization is set up via disulphide bond formation, catalysed by protein disulphide isomerase (PDI). In T. spiralis, some PDI family members have been identified but no localization is described and no antibodies specific for T. spiralis PDIs are available. In this work, computational approaches were used to search for non-described PDIs in the T. spiralis genome database and to check the cross-reactivity of commercial anti-human antibodies with T. spiralis orthologues. In addition to a previously described PDI (PDIA2), endoplasmic reticulum protein (ERp57/PDIA3), ERp72/PDIA4, and the molecular chaperones calreticulin (CRT), calnexin (CNX) and immunoglobulin-binding protein/glucose-regulated protein (BIP/GRP78), we identified orthologues of the human thioredoxin-related-transmembrane proteins (TMX1, TMX2 and TMX3) in the genome protein database, as well as ERp44 (PDIA10) and endoplasmic reticulum disulphide reductase (ERdj5/PDIA19). Immunocytochemical staining of paraffin sections of muscle infected by T. spiralis enabled us to localize some orthologues of the human PDIs (PDIA3 and TMX1) and the chaperone GRP78. A theoretical three-dimensional model for T. spiralis PDIA3 was constructed. The localization and characteristics of the predicted linear B-cell epitopes and amino acid sequence of the immunogens used for commercial production of anti-human PDIA3 antibodies validated the use of these antibodies for the immunolocalization of T. spiralis PDIA3 orthologues. These results suggest that further study of the role of the PDIs and chaperones during nurse cell formation is desirable.
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Genoma de los Helmintos , Proteínas del Helminto/genética , Isomerasas/genética , Trichinella spiralis/enzimología , Animales , Bases de Datos de Ácidos Nucleicos , Chaperón BiP del Retículo Endoplásmico , Femenino , Humanos , Datos de Secuencia Molecular , Familia de Multigenes , Ratas , Trichinella spiralis/genéticaRESUMEN
The worldwide obesity pandemic requires the use of anti-obesity drugs. Sibutramine is an anti-obesity drug that has been used worldwide but is indiscriminately consumed in Brazil. Several studies have demonstrated that sibutramine promotes weight loss and weight maintenance, but several side effects have been associated with its systematic consumption. For this reason, sibutramine was withdrawn from the European and American markets, but still remains legal for use in Brazil. Studies have shown that a 5-10% reduction in body weight results in outstanding health benefits for obese patients. However, in order to promote significant weight loss, it is necessary to use sibutramine for at least 2 years. This long-term exposure has carcinogenic potential, as sibutramine causes DNA damage. Thus, this study evaluated the in vivo mutagenic potential of sibutramine alone (5, 7, 10, 15, and 20 mg/kg) and in association with Spirulina maxima (150 and 300 mg/kg), a cyanobacterium with antioxidant potential, using the polychromatic erythrocyte micronucleus test. Our results reinforced the mutagenic potential of sibutramine alone, which showed a time-dependent action. Combinatory treatments with S. maxima were not able to reduce the genotoxicity of sibutramine. These results were confirmed in vitro with the cytokinesis-blocked micronucleus test. In conclusion, our data showed that new alternative anti-obesity treatments are needed since the consumption of sibutramine can increase the risk of cancer in overweight patients.
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Depresores del Apetito/farmacocinética , Ciclobutanos/farmacología , Mutágenos/farmacología , Spirulina/fisiología , Adolescente , Adulto , Fármacos Antiobesidad/farmacología , Fármacos Antiobesidad/toxicidad , Depresores del Apetito/administración & dosificación , Depresores del Apetito/toxicidad , Brasil , Ciclobutanos/administración & dosificación , Ciclobutanos/toxicidad , Femenino , Humanos , Linfocitos/efectos de los fármacos , Linfocitos/metabolismo , Masculino , Micronúcleos con Defecto Cromosómico/efectos de los fármacos , Pruebas de Micronúcleos , Mutágenos/administración & dosificación , Mutágenos/toxicidad , Reticulocitos/efectos de los fármacos , Reticulocitos/metabolismo , Adulto JovenRESUMEN
Schistosomiasis is a parasitic disease caused by flatworms of the genus Schistosoma. Among the Schistosoma species known to infect humans, S. mansoni is the most frequent cause of intestinal schistosomiasis in sub-Saharan Africa and South America: the World Health Organization estimates that about 200,000 deaths per year result from schistosomiasis in sub-Saharan Africa alone. The Schistosoma life cycle requires two different hosts: a snail as intermediate host and a mammal as definitive host. People become infected when they come into contact with water contaminated with free-living larvae (e.g. when swimming, fishing, washing). Although S. mansoni has mechanisms for escaping the host immune system, only a minority of infecting larvae develop into adults, suggesting that strain selection occurs at the host level. To test this hypothesis, we compared the Belo Horizonte (BH) strain of S. mansoni recovered from definitive hosts with different immunological backgrounds using random amplification of polymorphic DNA-polymerase chain reaction (RAPD-PCR). Schistosoma mansoni DNA profiles of worms obtained from wild-type (CD1 and C57BL/6J) and mutant (Jα18- / - and TGFßRIIdn) mice were analysed. Four primers produced polymorphic profiles, which can therefore potentially be used as reference biomarkers. All male worms were genetically distinct from females isolated from the same host, with female worms showing more specific fragments than males. Of the four host-derived schistosome populations, female and male adults recovered from TGFßRIIdn mice showed RAPD-PCR profiles that were most similar to each other. Altogether, these data indicate that host immunological backgrounds can influence the genetic diversity of parasite populations.
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Variación Genética , Ratones/inmunología , Schistosoma mansoni/genética , Esquistosomiasis mansoni/inmunología , Animales , Modelos Animales de Enfermedad , Femenino , Masculino , Ratones/parasitología , Ratones Endogámicos C57BL , Ratones Noqueados , Filogenia , Técnica del ADN Polimorfo Amplificado Aleatorio , Schistosoma mansoni/clasificación , Schistosoma mansoni/aislamiento & purificación , Schistosoma mansoni/fisiología , Esquistosomiasis mansoni/parasitologíaRESUMEN
Proteins containing repetitive amino acid domains are widespread in all life forms. In parasitic organisms, proteins containing repeats play important roles such as cell adhesion and invasion and immune evasion. Therefore, extracellular and intracellular parasites are expected to be under different selective pressures regarding the repetitive content in their genomes. Here, we investigated whether there is a bias in the repetitive content found in the predicted proteomes of 6 exclusively extracellular and 17 obligate intracellular protozoan parasites, as well as 4 free-living protists. We also attempted to correlate the results with the distinct ecological niches they occupy and with distinct protein functions. We found that intracellular parasites have higher repetitive content in their proteomes than do extracellular parasites and free-living protists. In intracellular parasites, these repetitive proteins are located mainly at the parasite surface or are secreted and are enriched in amino acids known to be part of N- and O-glycosylation sites. Furthermore, in intracellular parasites, the developmental stages that are able to invade host cells express a higher proportion of proteins with perfect repeats relative to other life cycle stages, and these proteins have molecular functions associated with cell invasion. In contrast, in extracellular parasites, degenerate repetitive motifs are enriched in proteins that are likely to play roles in evading host immune response. Altogether, our results support the hypothesis that both the ability to invade host cells and to escape the host immune response may have shaped the expansion and maintenance of perfect and degenerate repeats in the genomes of intra- and extracellular parasites.
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Alveolados/genética , Amebozoos/genética , Diplomonadida/genética , Proteínas Protozoarias/genética , Trypanosomatina/genética , Alveolados/inmunología , Amebozoos/inmunología , Animales , Diplomonadida/inmunología , Interacciones Huésped-Parásitos , Humanos , Evasión Inmune/genética , Procesamiento Proteico-Postraduccional , Proteoma/química , Proteoma/genética , Proteoma/metabolismo , Proteínas Protozoarias/química , Proteínas Protozoarias/metabolismo , Secuencias Repetitivas de Aminoácido , Trypanosomatina/inmunologíaRESUMEN
Obesity is one of the most important nutritional disorders, and can be currently considered as an epidemic. Although there are few weight reduction drugs available on the market, some new drug candidates have been proposed, including Cordia ecalyculata, a Brazilian plant with anorectic properties, and Spirulina maxima, a cyanobacterium with antioxidant and anti-genotoxic activity. In this study, we evaluated the mutagenic potential of C. ecalyculata at doses of 150, 300, and 500 mg/kg alone and in association with S. maxima at doses of 75, 150, and 250 mg/kg, respectively, through an in vivo micronucleus test, using mice of both sexes, and an in vitro micronucleus test and comet assay, using human peripheral blood. For all tests, cyclophosphamide was used as a positive control. The results showed that treatment of 300 mg/kg C. ecalyculata and the combination treatment of 500 mg/kg C. ecalyculata with 250 mg/kg S. maxima resulted in anorectic effects. The mutagenic tests did not reveal any clastogenic or genotoxic activity for any treatment, indicating that these candidates could be marketed as weight-reduction drugs. Moreover, the drugs contain chemo-preventive substances that can protect against tumorigenesis, which has been associated with obesity.
Asunto(s)
Depresores del Apetito/farmacología , Peso Corporal/efectos de los fármacos , Cordia/química , Extractos Vegetales/farmacología , Spirulina/química , Adolescente , Adulto , Animales , Ensayo Cometa , Ciclofosfamida/farmacología , Fragmentación del ADN/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Leucocitos Mononucleares/citología , Leucocitos Mononucleares/efectos de los fármacos , Masculino , Ratones , Pruebas de Micronúcleos , Pruebas de MutagenicidadRESUMEN
AIM: Strenuous exercise can enhance plasma levels of pro- and anti-inflammatory cytokines. Increases in plasma tumor necrosis factor-alpha (TNF-α) are followed rapidly by a rise in its natural inhibitors, soluble TNF receptors (sTNFRs). These inhibitors likely prevent an over-response to the cytokine. Aims of the present study were: 1) analyze plasma sTNFR1 at different time-points in response to a strenuous off-road cycling competition; 2) evaluate whether plasma levels of sTNFR1 correlate to increased blood lactate levels on completion of the exercise. METHODS: Eight trained off-road cyclists took part in this study and the data collection occurred during an official off-road race. Blood samples were collected pre-race, immediately post-race, and 1 h, 2 h and 24 h during the recovery period, for plasma sTNFR1 and blood lactate determination. RESULTS: Increase in sTNFR1 plasma levels were observed immediately post-race, 1 h and 2 h post-race (P<0.01), returning to baseline levels at the end of the recovery period (24 h). Significant correlation between plasma levels of sTNFR1 and blood lactate concentration were observed at the end of the race (r=0.925; P<0.001). CONCLUSION: An off-road cycling race stimulated an increase in plasma sTNFR1 and this anti-inflammatory molecule was positively correlated to blood lactate concentration. This result reinforces the view that exercise intensity influences the increase in plasma anti-inflammatory molecules.
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Ciclismo/fisiología , Conducta Competitiva , Esfuerzo Físico/fisiología , Receptores Tipo I de Factores de Necrosis Tumoral/sangre , Humanos , Lactatos/sangre , Masculino , Volumen Plasmático , Encuestas y Cuestionarios , Adulto JovenRESUMEN
AIM: Physical exercise and soybean intake reduced oxidative stress and atherosclerosis. However, the associated effects of both interventions have not been yet investigated. Thus, we aimed to evaluate the combined effects of swimming and soybean intake on lipid profile, oxidative stress and atherogenesis. METHODS: Ten-week-old male Low-Density Lipoprotein Receptor Knockout mice were divided into 4 groups (N.=8 for each group): control diet without swimming; control diet with swimming; soybean rich diet without swimming and soybean rich diet with swimming. Diets were based on American Institute of Nutrition 93 Growth. The diet of soybean groups was made by soybean extract contained isoflavones. The animals in the exercise groups underwent a 6-week swimming program five times per week. Plasma lipid profile was determined using enzymatic kits. Oxidative stress was measured by thiobarbituric acid reactive substances, hydroperoxide and the lipid oxidation resistance determinations. Atherosclerotic lesions were calculated by morphometry. RESULTS: Soybean intake increased high density lipoprotein cholesterol. Moreover, soybean and exercise individually reduced hepatic oxidative stress and atherogenesis in aortic valve. No additional effect was seen in soybean+exercise group. However, the association of soybean and exercise reduced the percentage of lesion area in arch, thoracic and abdominal aorta and increased serum antioxidant potential. CONCLUSION: Soybean intake and swimming are beneficial in reducing atherosclerosis besides improving lipid profile and reducing lipid peroxidation. The association of soybean and swimming aggregates beneficial effects in serum antioxidant potential and in aorta lesion.
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Aterosclerosis/dietoterapia , Terapia por Ejercicio , Glycine max/metabolismo , Estrés Oxidativo , Animales , Aterosclerosis/metabolismo , Aterosclerosis/patología , Aterosclerosis/terapia , Terapia Combinada , Humanos , Masculino , Ratones , Ratones Noqueados , Glycine max/química , NataciónRESUMEN
Persistence, defined as the probability that a signal has not reached a threshold up to a given observation time, plays a crucial role in the theory of random processes. Often, persistence decays algebraically with time with non trivial exponents. However, general analytical methods to calculate persistence exponents cannot be applied to the ubiquitous case of non-Markovian systems relaxing transiently after an imposed initial perturbation. Here, we introduce a theoretical framework that enables the non-perturbative determination of persistence exponents of Gaussian non-Markovian processes with non stationary dynamics relaxing to a steady state after an initial perturbation. Two situations are analyzed: either the system is subjected to a temperature quench at initial time, or its past trajectory is assumed to have been observed and thus known. Our theory covers the case of spatial dimension higher than one, opening the way to characterize non-trivial reaction kinetics for complex systems with non-equilibrium initial conditions.
RESUMEN
The aim of this study was to compare the maximal lactate steady state (MLSS) and ventilatory threshold (VT) under different environments (TEMP: 22°C; and HOT: 40°C; 50% RH). 8 male subjects (age 23.9±2.4 years, body mass 75.9±7.3 kg and VO2(max) 47.8±4.9 mL·kg(-1)·min(-1)) performed a series of tests to determine the peak workload (W(peak)), VT and MLSS on a cycle ergometer. W(peak) was higher in the TEMP as compared to the HOT condition (225±9 W vs. 195±8 W, respectively; p<0.05). The workload at MLSS was higher at 22°C (180±11 W) than 40°C (148±11 W; p<0.05), as well as VT at 22°C (156±9 W) was higher than 40°C (128±6 W). Likewise, the blood lactate concentration at MLSS was higher at 22°C (5.60±0.26 mM) than 40°C (4.22±0.48 mM; p<0.05). The mean of heart rate (HR) was not statistically different between TEMP (168±3 bpm) and HOT (173±3 bpm) at MLSS, despite being different at trials between the 25(th) and the 30(th) min of exercise. The HR at VT was significantly higher in HOT (153±4 bpm) as compared to the TEMP (145±2 bpm). Our results suggest that environmental conditions may influence the determination of MLSS and VT. Moreover, VT was appropriate for estimation of the workload at MLSS in the HOT.
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Ciclismo/fisiología , Calor , Ácido Láctico/sangre , Consumo de Oxígeno/fisiología , Adulto , Prueba de Esfuerzo , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Esfuerzo Físico , Temperatura , Factores de Tiempo , Adulto JovenRESUMEN
Hemophagocytic Syndrome is a clinical condition characterized by the activation of either macrophages or histiocytes with a prominent hemophagocytosis feature in the bone marrow and other reticuloendothelial systems. It leads to the phagocytosis of erythrocytes, leukocytes, platelets and their precursors. The presence of hemophagocytosis can be associated to infections, malignancies, autoimmune diseases, drugs and a variety of other medical conditions. We report a case of a previously healthy 36 year-old woman that developed hemophagocytosis at the same time that fulfilled diagnostic criteria for systemic lupus erythematosus. Lupus related hemophagocytic syndrome is a rare and potentially fatal entity. It offers significant differential diagnosis challenges and requires urgent therapeutic intervention. There are only few cases reported in the literature. However, much is still needed in order to better understand its causes, all the immunopathogenic mechanisms, as well as its clinical and therapeutic aspects.
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Lupus Eritematoso Sistémico/complicaciones , Linfohistiocitosis Hemofagocítica/etiología , Enfermedad Aguda , Adulto , Autoanticuerpos/sangre , Médula Ósea/patología , Ciclofosfamida/uso terapéutico , Femenino , Ferritinas/análisis , Histiocitos/patología , Humanos , Inmunosupresores/uso terapéutico , Riñón/patología , Lupus Eritematoso Sistémico/sangre , Lupus Eritematoso Sistémico/diagnóstico , Lupus Eritematoso Sistémico/tratamiento farmacológico , Nefritis Lúpica/etiología , Nefritis Lúpica/patología , Linfohistiocitosis Hemofagocítica/sangre , Linfohistiocitosis Hemofagocítica/diagnóstico , Linfohistiocitosis Hemofagocítica/tratamiento farmacológico , Células Mesangiales/patología , Metilprednisolona/uso terapéuticoRESUMEN
The goals of the present study were to investigate the feeding rates of Scartella cristata, accounting for different water temperature regimes, and to analyse spatial and seasonal variations in its diet. The feeding rate of S. cristata was higher in warmer waters and was not correlated with season. A typical herbivorous diel feeding pattern was observed, with a steady increase in bite rate throughout the morning until a plateau in the early afternoon, followed by an abrupt decrease until the end of the daylight period. The gut contents of S. cristata included at least 41 different items. Detritus and algae (mainly filamentous) comprised most of the bulk of S. cristata's diet. Scartella cristata also exhibited significant seasonal and spatial variability in its diet. This study highlights the importance of detritus within the epilithic algal matrix in the diet of S. cristata and pinpoints that, as in coral reefs, the detrital pathway exerts an important role in the trophodynamics of subtropical rocky shores where these fish are abundant.
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Dieta , Ecosistema , Conducta Alimentaria/fisiología , Perciformes/fisiología , Estaciones del Año , Animales , Densidad de PoblaciónRESUMEN
Scorpion stings are a public health problem in Brazil, with most incidents involving the species Tityus serrulatus. Some T. serrulatus toxins may act as immunogens for the production of a specific anti-venom, but many of the component toxins remain poorly characterized. Here, we describe the immunological characteristics of the toxin Ts1 (also known as TsVII and Ts-gamma) and evaluate production of neutralizing antibodies against the crude venom of T. serrulatus. Recombinant Ts1 with one copy (Ts1(1)) or two copies in tandem (Ts1(2)) was expressed in BL21 (DE3) cells. Rabbits and mice were immunized with the recombinant proteins (inclusion bodies) and then tested for production of neutralizing antibodies. Neutralization assays showed that anti-Ts1(1) and anti-Ts1(2) protected animals challenged with T. serrulatus crude venom and native Ts1. Thus, Ts1 could be used in a mixed "cocktail" of immunogens for T. serrulatus anti-venom production.
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Antivenenos/biosíntesis , Proteínas de Insectos/inmunología , Venenos de Escorpión/antagonistas & inhibidores , Animales , Formación de Anticuerpos , Antivenenos/inmunología , Antivenenos/aislamiento & purificación , Secuencia de Bases , Femenino , Proteínas de Insectos/química , Proteínas de Insectos/genética , Dosificación Letal Mediana , Masculino , Ratones , Datos de Secuencia Molecular , Conejos , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/metabolismo , Venenos de Escorpión/química , Venenos de Escorpión/genética , Venenos de Escorpión/inmunología , Venenos de Escorpión/toxicidadRESUMEN
Three glycosilated flavonoids (diosmin, hesperidin and naringin) and respective aglycones were characterized in terms of their apparent ionisation constants and bidirectional permeability using the cellular model Caco-2 as well as the artificial membrane model PAMPA. Ionisation curves were established by capillary electrophoresis. It was confirmed that significant amounts of the aglycones are ionised at physiological pH whereas the glycosides are in the neutral form. Permeation was not detected for the glycosides in either the apical-to-basolateral or basolateral-to-apical directions confirming the need for metabolism before absorption through the intestinal membrane. The aglycones permeated in both directions with apparent permeabilities (P(app)) in the range of 1-8x10(-5) cm/s. The results from both in vitro methods correlated providing some evidence of passive transport; however, the hypothesis of active transport cannot be excluded particularly in the case of diosmetin. Metabolism of the aglycones was detected with the cell model, more extensively when loading in the apical side. Some of the metabolites were identified as glucuronide conjugates by enzymatic hydrolysis.
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Flavanonas/metabolismo , Flavanonas/farmacología , Flavonas/metabolismo , Flavonas/farmacología , Absorción Intestinal/efectos de los fármacos , Células CACO-2 , Electroforesis Capilar , Flavanonas/química , Flavonas/química , Humanos , Concentración de Iones de Hidrógeno , Membranas Artificiales , Estructura Molecular , Peso MolecularRESUMEN
This study investigated the effects of environmental variation on assemblages of dragonfly larvae (Odonata). We hypothesize that there is a significant correlation between species richness, species composition, and abundance of Odonata individuals, and habitat integrity and abiotic variables. To test this hypothesis, we sampled odonate larvae at 12 streams in the Suiá-Miçú River basin in Mato Grosso, Brazil, during three different periods of the year. Local physical and chemical variables (temperature, pH, turbidity, electrical conductivity (EC), dissolved oxygen (DO), total dissolved solids (TDS), and oxidation reduction potential (ORP)) were measured at each site using a multi-parameter probe, and integrity was assessed using the Habitat Integrity Index (HII). The variation in richness, abundance, and composition of Odonata species was related to the environmental variables analyzed, primarily by the abiotic factors pH, electrical conductivity, dissolved oxygen, total dissolved solids, and oxidation reduction potential. Our hypothesis was corroborated for the suborder Anisoptera, which showed a significant relationship with these variables, whereas Zygoptera was only related to pH. Our results show the importance of physical and chemical conditions in ecological studies using Odonata larvae as tools for the management and conservation of freshwater ecosystems.
Asunto(s)
Distribución Animal , Ecosistema , Odonata , Ríos , Animales , Brasil , Conservación de los Recursos Naturales , LarvaRESUMEN
Doxorubicin has been largely used in anticancer therapy in adults, adolescents, and children. The efficacy of l-carnitine as an antioxidant substance has been confirmed both in humans and rats. Carnitine, present in testis and epididymis, is involved in sperm maturation. It is also effective in infertility treatment. As a continuation of a previous study, we evaluated whether some spermatic qualitative parameters, DNA integrity, chromatin structure, and fertility status, could be ameliorated by the carnitine treatment in adult rats, which were subsequently exposed to doxorubicin at pre-puberty. Pre-pubertal male rats were distributed into four groups: Sham Control; Doxorubicin; l-carnitine; l-carnitine + Doxorubicin (l-carnitine injected 1 h before doxorubicin). At 100 days of age, all groups were reassigned into two sets: One set was submitted to the evaluation of sperm motility, acrosome integrity, mitochondrial activity, sperm chromatin structure analysis (SCSA), and evaluation of the oxidative stress. The other set of rats was destined to the evaluation of reproductive competence. The percentage of spermatozoa with intact acrosome integrity was higher in the Carnitine+Doxorubicin group when compared with the Doxorubicin group. However, sperm motility and mitochondrial activity were not improved by carnitine pre-treatment. Both values of malondialdehyde and nitrite (indirect measurement of nitric oxide) concentrations were statistically higher in the only doxorubicin-treated group when compared to the Carnitine + Doxorubicin group. Fertility index and implantation rate were lower in Doxorubicin group, when compared to Carnitine + Doxorubicin group. Moreover, the percentage of spermatozoa with damaged DNA was higher in the Doxorubicin-treated group when compared to the Carnitine+Doxorubicin group. l-carnitine, when administered before doxorubicin, partially preserved the acrosome integrity, an important feature related to sperm fertilization ability that positively correlated with the reproductive competence and sperm DNA integrity at adulthood. In conclusion, l-carnitine attenuated the long-term alterations caused by doxorubicin in the germ cells and improved male reproductive capacity in adulthood.