RESUMEN
Mercury (Hg) is a widespread pollutant across estuarine and coastal areas, raising concern on its potential impact on aquatic organisms. Hg may origin from natural and anthropogenic sources, being persistent and potentially toxic to biota, ultimately representing a serious risk to human health. Hg accumulation and toxicity may also induce reactive oxygen species (ROS) production in marine organisms, responsible for cell and tissue damage. Additionally, the temperature is undoubtedly an important environmental factor to consider regarding accumulation, due to its marked influence on the physiology and ecology of aquatic organisms. This study aimed to investigate the effect of different temperature scenarios (15, 20 and 25 °C) on the Hg accumulation in Pomatoschistus microps (Krøyer, 1838) liver and muscle, as well as on oxidative stress responses and energy metabolism, after short-term exposure to a naturally contaminated sediment with an environmentally relevant [Hg] (1.2 µg g-1). The results showed that Hg accumulation tends to increase along the temperature gradient with higher values of Hg accumulated in liver than in muscle tissue. The action of antioxidant enzymes and stress proteins seems to be effective in combating oxidative stress in the liver. Despite the action of antioxidant defences in the muscle, oxidative damage was observed at the protein level concomitantly with a decrease in aerobic energy production after exposure to Hg at higher temperatures. These findings are ecologically relevant and highlight the importance of further investigation of combined effects of Hg and other stressors, especially in a scenario of a changing climate where events leading to rapid alterations on water parameters are more frequent.
Asunto(s)
Mercurio , Contaminantes Químicos del Agua , Animales , Humanos , Mercurio/toxicidad , Estrés Oxidativo , Temperatura , Agua , Contaminantes Químicos del Agua/toxicidadRESUMEN
Amorphous S-flurbiprofen was obtained by the melt quench/cooling method. Dielectric measurements performed in the isochronal mode, conventional and temperature modulated differential scanning calorimetry (TMDSC) studies showed a glass transition, recrystallization, and melting. The different parameters characterizing the complex molecular dynamics of amorphous S-flurbiprofen that can have influence on crystallization and stability were comprehensively characterized by dielectric relaxation spectroscopy experiments (isothermal mode) covering a wide temperature (183 to 408 K) and frequency range (10(-1) to 10(6) Hz): width of the α-relaxation (ßKWW), temperature dependence of α-relaxation times (τα), fragility index (m), relation of the α-relaxation with the ß-secondary relaxation, and the breakdown of the Debye-Stokes-Einstein (DSE) relationship between the structural relaxation time and dc-conductivity (σdc) at deep undercooling close to Tg. The ß-relaxation, observed in the glassy as well as in the supercooled state was identified as the genuine Johari-Goldstein process, attributed to localized motions and regarded as the precursor of the α-relaxation as suggested in the coupling model. A separation of about 6 decades between the α- and ß-relaxation was observed at Tg; this decoupling decreased on increasing temperature, and both processes merged at Tαß = 295 K. The temperature dependence of the α-relaxation time, τα, was described by two Vogel-Fulcher-Tammann-Hesse equations, which intercept at a crossover temperature, TB = 290 K, close to the splitting temperature between the α- and ß-relaxation. From the low temperature VFTH equation, a Tg(DRS) = 265.2 was estimated (at τα =100 s) in good agreement with the calorimetric value (Tg,onset,TMDSC = 265.6 K), and a fragility or steepness index m = 113 was calculated allowing to classify S-flurbiprofen as a fragile glass former. The α-relaxation spectra were found to be characterized by a relatively large degree of nonexponentiality (ßKWW = 0.52). A breakdown of the DSE log10 σdc - log10 τ relation was observed revealing an enhancement of translational ionic motions in comparison with the orientational molecular motions as the glass transition temperature Tg is approached from above.
Asunto(s)
Flurbiprofeno/química , Vidrio/química , Rastreo Diferencial de Calorimetría , Cristalización , Espectroscopía Dieléctrica , Conductividad Eléctrica , Modelos Moleculares , Simulación de Dinámica Molecular , Transición de Fase , Termogravimetría , Temperatura de TransiciónRESUMEN
We evaluated the effects of recreational football training combined with calorie-restricted diet (football + diet) vs calorie-restricted diet alone (diet) on aerobic fitness, lipid profile, and insulin resistance indicators in type 2 diabetes (T2D) patients. Forty-four T2D patients aged 48-68 years (27 females, 17 males) were randomly allocated to the football + diet group (FDG; n = 22) or to the diet group (DG; n = 22), of whom 19 FDG and 15 DG subjects completed the study. The football training was performed for 3 × 40 min/week for 12 weeks. Dual-energy X-ray absorptiometry scanning, treadmill testing, and fasting blood samplings were performed pre and post-intervention. After 12 weeks, maximal oxygen uptake (VO2max ) was elevated (P < 0.05) by 10 ± 4% in FDG but not in DG (-3 ± 4%, P < 0.05). After 12 weeks, reductions in blood triglycerides (0.4 ± 0.1 mmol/L), total cholesterol (0.6 ± 0.2 mmol/L), low-density lipoprotein, and very low-density lipoprotein levels were observed only in FDG. Fat mass decreased (P < 0.05) by 3.4 ± 0.4 kg in FDG and 3.7 ± 0.4 kg in DG. The lower (P < 0.05) glucagon and homeostatic model assessment of insulin resistance indicated an improvement in insulin sensitivity in FDG. In conclusion, football combined with restricted diet was effective in enhancing VO2max , reducing total cholesterol and triglycerides, and increasing insulin sensitivity, potentially providing better tools for the prevention of T2D complications than diet alone.
Asunto(s)
Colesterol/sangre , Diabetes Mellitus Tipo 2/terapia , Terapia por Ejercicio/métodos , Resistencia a la Insulina , Aptitud Física , Fútbol/fisiología , Triglicéridos/sangre , Anciano , Biomarcadores/sangre , Glucemia/metabolismo , Brasil , Restricción Calórica , Terapia Combinada , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/fisiopatología , Femenino , Frecuencia Cardíaca , Humanos , Masculino , Persona de Mediana Edad , Consumo de Oxígeno , Resultado del TratamientoRESUMEN
The laboratory diagnosis of rabies is of fundamental importance to the evaluation of suspected cases of rabies virus (RABV) infection. Confirmation of direct fluorescent antibody test (DFAT) results via viral isolation (VI) is recommended, and the mouse inoculation test (MIT) is being replaced by the rabies tissue culture infection (RTCIT) test for ethical reasons. We evaluated 6.514 results from central nervous system (CNS) samples of different animals analyzed at the Pasteur Institute between 2008 and 2016 using the DFAT, RTCIT and MIT techniques and evaluated their concordance, sensitivity, specificity, and accuracy indices. The DFAT technique presented the best sensitivity (93.58 %), specificity (95.90 %), and accuracy (95.67 %) results. The RTCIT values of sensitivity, specificity and accuracy (70.42 %, 86.16 % and 84.62 % respectively) were lower than those of DFAT. The concordance between RTCIT and DFAT was moderate, with a kappa quotient k = 0.341. The MIT values of sensitivity, specificity, and accuracy were 89.58 %, 100 % and 98.97 % respectively. The concordance between MIT and DFAT was substantial, with a k value of 0.720. DFAT, considered the "gold standard", was effective in all animals except horses. Our analyses evidenced that DFAT presents satisfactory results, although RTCIT did not appear favorable as a confirmatory technique.
Asunto(s)
Virus de la Rabia , Rabia , Animales , Técnica del Anticuerpo Fluorescente Directa/métodos , Caballos , Pruebas Inmunológicas , Ratones , Rabia/diagnóstico , Rabia/veterinaria , Sensibilidad y EspecificidadRESUMEN
STATEMENT OF PROBLEM: Customized glass fiber posts using CAD-CAM technology have been suggested for restoring endodontically treated teeth. However, how weakened or non-weakened roots restored with anatomical CAD-CAM posts behave under cyclic fatigue is not clear. OBJECTIVE: To evaluate the load-bearing capacity under fatigue (fatigue failure load [FFL], the number of cycles for failure [CFF], and survival probabilities) and fracture pattern of weakened and non-weakened roots restored with CAD-CAM fiber post and cores, metal cast-post-core, and prefabricated fiber post and resin core. METHODS AND MATERIALS: A total of 60 crack-free bovine incisor roots (13 mm in length) with standard geometry were obtained and randomly allocated considering the factor "root condition" in two levels (weakened and non-weakened). Thus, half of the roots were weakened to obtain a wall thickness of 0.5 mm. After that, the endodontic treatment was executed, all roots embedded with acrylic resin and the specimens randomly allocated (n=10) considering the factor "post system" in three levels (CAD-CAM: CAD-CAM milled glass-fiber post and core; MBC: metallic-based post and core; and FRC: prefabricated glass-fiber post and composite resin core). The posts were luted with a dual-cure self-adhesive luting agent. Then, all teeth received a metallic crown. An initial load of 100 N at 20 Hz for 5000 cycles was applied for the step-stress fatigue test, followed by incremental steps of 50 N for 20,000 cycles each step, up to failure. A fracture pattern analysis was performed. RESULTS: CAD-CAM fiber post (FFL: 865 N; CFF: 311,000 cycles) presented similar fatigue performance (p>0.05) to FRC (FFL: 925 N; CFF: 335,000 cycles), with 100% of repairable fractures for non-weakened roots; however, both groups presented worse performance than MBC (p<0.05; FFL: 1265 N; CFF: 471,000 cycles) which led to 100% of catastrophic failures. No statistical difference was found in fatigue performance among the three systems for weakened roots (p>0.05; FFL: 1035-1170 N; CFF: 379,000-433,000 cycles), with a high rate of catastrophic failures. CONCLUSIONS: CAD-CAM fiber post presented similar fatigue performance to MBC and FRC approaches when restoring weakened roots. CADCAM was similar to FRC when restoring non-weakened roots, while MBC enhanced fatigue properties in this scenario.
Asunto(s)
Técnica de Perno Muñón , Fracturas de los Dientes , Diente no Vital , Animales , Bovinos , Cerámica , Resinas Compuestas/uso terapéutico , Diseño Asistido por Computadora , Análisis del Estrés Dental , Vidrio , Ensayo de Materiales , Propiedades de Superficie , Diente no Vital/terapia , Estudios CruzadosRESUMEN
Salivarian trypanosomes pose a substantial threat to livestock, but their full diversity is not known. To survey trypanosomes carried by tsetse in Tanzania, DNA samples from infected proboscides of Glossina pallidipes and G. swynnertoni were identified using fluorescent fragment length barcoding (FFLB), which discriminates species by size polymorphisms in multiple regions of the ribosomal RNA locus. FFLB identified the trypanosomes in 65 of 105 (61.9%) infected proboscides, revealing 9 mixed infections. Of 7 different FFLB profiles, 2 were similar but not identical to reference West African Trypanosoma vivax; 5 other profiles belonged to known species also identified in fly midguts. Phylogenetic analysis of the glycosomal glyceraldehyde phosphate dehydrogenase gene revealed that the Tanzanian T. vivax samples fell into 2 distinct groups, both outside the main clade of African and South American T. vivax. These new T. vivax genotypes were common and widespread in tsetse in Tanzania. The T. brucei-like trypanosome previously described from tsetse midguts was also found in 2 proboscides, demonstrating a salivarian transmission route. Investigation of mammalian host range and pathogenicity will reveal the importance of these new trypanosomes for the epidemiology and control of animal trypanosomiasis in East Africa.
Asunto(s)
Insectos Vectores/parasitología , Trypanosoma vivax/genética , Tripanosomiasis Africana/veterinaria , Moscas Tse-Tse/parasitología , Animales , ADN Protozoario/genética , Fluorescencia , Tracto Gastrointestinal/parasitología , Variación Genética , Gliceraldehído-3-Fosfato Deshidrogenasas/genética , Datos de Secuencia Molecular , Técnicas de Amplificación de Ácido Nucleico , Filogenia , Análisis de Secuencia de Proteína , Tanzanía/epidemiología , Trypanosoma vivax/clasificación , Tripanosomiasis Africana/epidemiología , Tripanosomiasis Africana/parasitologíaRESUMEN
Trypanosoma (Megatrypanum) theileri from cattle and trypanosomes of other artiodactyls form a clade of closely related species in analyses using ribosomal sequences. Analysis of polymorphic sequences of a larger number of trypanosomes from broader geographical origins is required to evaluate the clustering of isolates as suggested by previous studies. Here, we determined the sequences of the spliced leader (SL) genes of 21 isolates from cattle and 2 from water buffalo from distant regions of Brazil. Analysis of SL gene repeats revealed that the 5S rRNA gene is inserted within the intergenic region. Phylogeographical patterns inferred using SL sequences showed at least 5 major genotypes of T. theileri distributed in 2 strongly divergent lineages. Lineage TthI comprises genotypes IA and IB from buffalo and cattle, respectively, from the Southeast and Central regions, whereas genotype IC is restricted to cattle from the Southern region. Lineage TthII includes cattle genotypes IIA, which is restricted to the North and Northeast, and IIB, found in the Centre, West, North and Northeast. PCR-RFLP of SL genes revealed valuable markers for genotyping T. theileri. The results of this study emphasize the genetic complexity and corroborate the geographical structuring of T. theileri genotypes found in cattle.
Asunto(s)
Enfermedades de los Bovinos/epidemiología , Bovinos/parasitología , Filogenia , ARN Lider Empalmado/genética , Trypanosoma/clasificación , Trypanosoma/genética , Tripanosomiasis , Animales , Secuencia de Bases , Brasil/epidemiología , Búfalos/parasitología , Enfermedades de los Bovinos/parasitología , ADN Protozoario/análisis , ADN Protozoario/genética , ADN Ribosómico/análisis , ADN Ribosómico/genética , ADN Espaciador Ribosómico/análisis , ADN Espaciador Ribosómico/genética , Evolución Molecular , Genotipo , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , ARN Ribosómico/genética , ARN Ribosómico 5S/genética , Análisis de Secuencia de ADN , Trypanosoma/aislamiento & purificación , Tripanosomiasis/epidemiología , Tripanosomiasis/parasitología , Tripanosomiasis/veterinariaRESUMEN
In the implantation of forests, soil tillage can affect the soil fauna, but over the years, it is possible that forest development can recompose the biological indicators of soil quality. So, the aim of this study was to evaluate the influence of different periods of eucalyptus development on community of edaphic fauna. The experiment was carried out in forest areas in the municipality of Ametista do Sul, RS. The Experimental design was completely randomized with 6 treatments, once 4 of the treatments were with different ages of the Eucalyptus grandis (two, four, six and eight years after trasnplant - YAT); plus 2 control treatments: Native Forest and Soil Naked, with 7 collection points. To sample the edaphic fauna, it was used traps such as PROVID. Also, the edaphic fauna was sampled at the depth of 0-5 cm for the quantification of mites. It was carried out the counting of individuals at the level of order and family for the mites, the means of the groups were submitted to the Tukey test and comparisons by Orthogonal Contrasts and calculated indices of Biodiversity: Margalef Richness, Simpson dominance, Shannon diversity and Pielou uniformity. The results showed lower abundance of individuals in Naked soil, while the Native Forest presented the best Biodiversity indices. With eight years of implantation of eucalyptus there was recovered the biological quality of the soil expressed by the population of springtails. The population of oribatídeos mites increased expressively from the six years of implantation of eucalyptus.
Asunto(s)
Eucalyptus , Ácaros , Animales , Biodiversidad , Bosques , SueloRESUMEN
Microplastics (1 µm-5 mm), a ubiquitous and persistent marine pollutant, pose a severe threat to coral reefs when recently associated with physiological distress and increased diseases on corals. Studies conducted so far have only reported effects on scleractinian species. Knowledge about its effects on other corals (e.g. Order Zoantharia) remains uncovered, and responses at biochemical levels remain poorly documented. This study aimed to assess the potential effects induced by the presence of microplastics (1 and 10 mg L-1 low-density polyethylene, LDPE MP, or polyvinyl chloride, PVC MP) in the tropical and subtropical cosmopolitan species Zoanthus sociatus (order Zoantharia. Anthozoa: Hexacorallia), at organism level (survival and behaviour), endosymbionts (photosynthetic efficiency) and the cellular level (oxidative stress, detoxification capacity and energy metabolism). In a short-term exposure (96 h), this species was more sensitive to PVC MP. The presence of this polymer at a concentration of 10 mg L-1 caused a ten-fold higher adhesion to the coral epidermis, increased photosynthetic efficiency, lipid peroxidation, and antioxidant defences; without, however, inducing energetic costs. Although the observed physiological and biochemical effects did not compromise Z. sociatus survival in the short term, it does not rule out potential long-term (cumulative) effects that could endanger this and other physiologically similar species that underlie coral reefs.
Asunto(s)
Antozoos , Animales , Arrecifes de Coral , MicroplásticosRESUMEN
In this study, using a combined data set of SSU rDNA and gGAPDH gene sequences, we provide phylogenetic evidence that supports clustering of crocodilian trypanosomes from the Brazilian Caiman yacare (Alligatoridae) and Trypanosoma grayi, a species that circulates between African crocodiles (Crocodilydae) and tsetse flies. In a survey of trypanosomes in Caiman yacare from the Brazilian Pantanal, the prevalence of trypanosome infection was 35% as determined by microhaematocrit and haemoculture, and 9 cultures were obtained. The morphology of trypomastigotes from caiman blood and tissue imprints was compared with those described for other crocodilian trypanosomes. Differences in morphology and growth behaviour of caiman trypanosomes were corroborated by molecular polymorphism that revealed 2 genotypes. Eight isolates were ascribed to genotype Cay01 and 1 to genotype Cay02. Phylogenetic inferences based on concatenated SSU rDNA and gGAPDH sequences showed that caiman isolates are closely related to T. grayi, constituting a well-supported monophyletic assemblage (clade T. grayi). Divergence time estimates based on clade composition, and biogeographical and geological events were used to discuss the relationships between the evolutionary histories of crocodilian trypanosomes and their hosts.
Asunto(s)
Caimanes y Cocodrilos/parasitología , Evolución Biológica , ADN Ribosómico/genética , Gliceraldehído-3-Fosfato Deshidrogenasa (Fosforilante)/genética , Filogenia , Trypanosomatina/clasificación , África , Animales , América del Sur , Trypanosomatina/citología , Trypanosomatina/aislamiento & purificaciónRESUMEN
Microbial populations are primarily responsible for the decomposition of organic residues, the nutrients cycle, and the flow of energy inside of soil. The present study was undertaken to link soil microbiological and soil biochemical parameters with soil- and litter-quality conditions in the surface layer from 5 sites differing in plant cover, in stand age, and in land-use history. The aim was to see how strongly these differences affect the soil microbial attributes and to identify how microbiological processes and structures can be influenced by soil and litter quality. Soil and litter samples were collected from 5 sites according to different land use: preserved forest, nonpreserved forest, secondary forest, pasture, and eucalyptus plantation. Soil and litter microbial biomass and activity were analysed and DNA was extracted from soil. The DNA concentrations and soil microbial C and N correlated positively and significantly, suggesting that these are decisive nutrients for microbial growth and time required for microbial biomass renewal. The litter microbial biomass represented a source of C and N higher than soil microbial biomass and can be an important layer to contribute to tropical soil with low C and N availability. The litter quality influenced the litter and soil microbial biomass and activity and the soil bacterial diversity. The chemical and nutritional quality of the litter influenced the structure and microbial community composition in the eucalyptus plantation.
Asunto(s)
Biodiversidad , Desarrollo de la Planta , Microbiología del Suelo , Suelo/análisis , Biomasa , Brasil , Carbono/análisis , Dermatoglifia del ADN , ADN Bacteriano/aislamiento & purificación , Electroforesis en Gel de Poliacrilamida , Metagenoma , Nitrógeno/análisis , Desnaturalización de Ácido NucleicoRESUMEN
The development of anthelmintic resistance has made the search for alternatives to control gastrointestinal nematodes of small ruminants imperative. Among these alternatives are several medicinal plants traditionally used as anthelmintics. This work evaluated the efficacy of Cocos nucifera fruit on sheep gastrointestinal parasites. The ethyl acetate extract obtained from the liquid of green coconut husk fiber (LGCHF) was submitted to in vitro and in vivo tests. The in vitro assay was based on egg hatching (EHT) and larval development tests (LDT) with Haemonchus contortus. The concentrations tested in the EHT were 0.31, 0.62, 1.25, 2.5 and 5 mg ml(-1), while in the LDT they were 5, 10, 20, 40 and 80 mg ml(-1). The in vivo assay was a controlled test. In this experiment, 18 sheep infected with gastrointestinal nematodes were divided into three groups (n=6), with the following doses administered: G1-400 mg kg(-1) LGCHF ethyl acetate extract, G2-0.2 mg kg(-1) moxidectin (Cydectin) and G3-3% DMSO. The worm burden was analyzed. The results of the in vitro and in vivo tests were submitted to ANOVA and analyzed by the Tukey and Kruskal-Wallis tests, respectively. The extract efficacy in the EHT and LDT, at the highest concentrations tested, was 100% on egg hatching and 99.77% on larval development. The parameters evaluated in the controlled test were not statistically different, showing that despite the significant results of the in vitro tests, the LGCHF ethyl acetate extract showed no activity against sheep gastrointestinal nematodes.
Asunto(s)
Antihelmínticos/farmacología , Cocos/química , Hemoncosis/tratamiento farmacológico , Haemonchus/efectos de los fármacos , Fitoterapia/veterinaria , Extractos Vegetales/farmacología , Enfermedades de las Ovejas/tratamiento farmacológico , Análisis de Varianza , Animales , Antihelmínticos/uso terapéutico , Relación Dosis-Respuesta a Droga , Hemoncosis/parasitología , Hemoncosis/veterinaria , Haemonchus/crecimiento & desarrollo , Parasitosis Intestinales/tratamiento farmacológico , Parasitosis Intestinales/veterinaria , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Recuento de Huevos de Parásitos/veterinaria , Pruebas de Sensibilidad Parasitaria , Extractos Vegetales/uso terapéutico , Plantas Medicinales/química , Ovinos , Enfermedades de las Ovejas/parasitología , Estadísticas no ParamétricasRESUMEN
The objective of this study was to compare the results of an on-farm test, named Somaticell, with results of electronic cell counting and for milk somatic cell count (SCC) among readers. The Somaticell test correctly determined the SCC in fresh quarter milk samples. Correlation between Somaticell and electronic enumeration of somatic cells was 0.92 and kappa coefficient 0.82. Using a threshold of 205,000 cells/mL, the sensitivity and specificity for determination of intramammary infections were 91.3 and 96.0%, respectively. The SCC was greater for milk samples from which major mastitis pathogens were recovered. Minor variation among readers was observed and most likely associated with the mixing procedure. However, the final analysis indicated that this variation was not significant and did not affect the amount of samples classified as having subclinical mastitis. The on-farm test evaluated in this study showed adequate capacity of determining SCC on quarter milk samples and may be considered as an alternative for on-farm detection of subclinical mastitis.
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Recuento de Células/veterinaria , Industria Lechera/métodos , Leche/citología , Animales , Bovinos , Recuento de Células/métodos , Femenino , Mastitis Bovina/microbiología , Mastitis Bovina/patología , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
In this study, we addressed the phylogenetic and taxonomic relationships of Trypanosoma vivax and related trypanosomes nested in the subgenus Duttonella through combined morphological and phylogeographical analyses. We previously demonstrated that the clade T. vivax harbours a homogeneous clade comprising West African/South American isolates and the heterogeneous East African isolates. Herein we characterized a trypanosome isolated from a nyala antelope (Tragelaphus angasi) wild-caught in Mozambique (East Africa) and diagnosed as T. vivax-like based on biological, morphological and molecular data. Phylogenetic relationships, phylogeographical patterns and estimates of genetic divergence were based on SSU and ITS rDNA sequences of T. vivax from Brazil and Venezuela (South America), Nigeria (West Africa), and from T. vivax-like trypanosomes from Mozambique, Kenya and Tanzania (East Africa). Despite being well-supported within the T. vivax clade, the nyala trypanosome was highly divergent from all other T. vivax and T. vivax-like trypanosomes, even those from East Africa. Considering its host origin, morphological features, behaviour in experimentally infected goats, phylogenetic placement, and genetic divergence this isolate represents a new genotype of trypanosome closely phylogenetically related to T. vivax. This study corroborated the high complexity and the existence of distinct genotypes yet undescribed within the subgenus Duttonella.
Asunto(s)
Antílopes/parasitología , Filogenia , Trypanosoma vivax/clasificación , Trypanosoma vivax/genética , Tripanosomiasis Africana/veterinaria , África Oriental , África Occidental , Animales , Bovinos , ADN Protozoario/análisis , ADN Espaciador Ribosómico/análisis , Genotipo , Enfermedades de las Cabras/parasitología , Cabras , Análisis de Secuencia de ADN , América del Sur , Trypanosoma vivax/aislamiento & purificación , Tripanosomiasis Africana/parasitología , Tripanosomiasis Bovina/parasitologíaRESUMEN
Blood examination by microhaematocrit and haemoculture of 459 snakes belonging to 37 species revealed 2.4% trypanosome prevalence in species of Viperidae (Crotalus durissus and Bothrops jararaca) and Colubridae (Pseudoboa nigra). Trypanosome cultures from C. durissus and P. nigra were behaviourally and morphologically indistinguishable. In addition, the growth and morphological features of a trypanosome from the sand fly Viannamyia tuberculata were similar to those of snake isolates. Cross-infection experiments revealed a lack of host restriction, as snakes of 3 species were infected with the trypanosome from C. durissus. Phylogeny based on ribosomal sequences revealed that snake trypanosomes clustered together with the sand fly trypanosome, forming a new phylogenetic lineage within Trypanosoma closest to a clade of lizard trypanosomes transmitted by sand flies. The clade of trypanosomes from snakes and lizards suggests an association between the evolutionary histories of these trypanosomes and their squamate hosts. Moreover, data strongly indicated that these trypanosomes are transmitted by sand flies. The flaws of the current taxonomy of snake trypanosomes are discussed, and the need for molecular parameters to be adopted is emphasized. To our knowledge, this is the first molecular phylogenetic study of snake trypanosomes.
Asunto(s)
Colubridae/parasitología , Filogenia , Trypanosoma/clasificación , Trypanosoma/genética , Tripanosomiasis/veterinaria , Viperidae/parasitología , Animales , Bothrops/clasificación , Bothrops/parasitología , Colubridae/clasificación , Crotalus/clasificación , Crotalus/parasitología , ADN Protozoario/análisis , ADN Ribosómico/análisis , Evolución Molecular , Interacciones Huésped-Parásitos , Datos de Secuencia Molecular , Psychodidae/parasitología , Análisis de Secuencia de ADN , Trypanosoma/fisiología , Trypanosoma/ultraestructura , Tripanosomiasis/parasitología , Tripanosomiasis/transmisión , Viperidae/clasificaciónRESUMEN
The traditional techniques to measure heat production (HP) are calorimetry (direct and indirect) and comparative slaughter. Both methods are expensive and require extensive amounts of time and infrastructure. Infrared thermography (IRT) could be a faster and less expensive alternative to estimate cattle HP. The objective of this project was to evaluate the use of the IRT technique as an indicator of HP in cattle. A total of 24 bulls (12 Nellore and 12 Black Angus) with initial BW of 380 ± 7 kg were used. Initially, 4 animals of each breed were harvested (baseline animals) and simple regressions were developed for each breed from these baseline animals to estimate the initial chemical composition of the remaining bulls. Eight animals of each breed were fed a silage/concentrate diet for ad libitum intake in individual stalls. On the 25th, 50th, and 75th experimental day, infrared thermal images (Fluke Ti 55ft; Fluke Corporation) were taken of each animal's face to access skin and ocular surface temperatures. A metabolism trial was conducted to estimate the ME intake (MEI). After 84 experimental days, the cattle were harvested and retained energy (RE) and HP were calculated. The data were analyzed using the MIXED and REG procedures of SAS adopting a significance level of 0.05. Angus cattle had a greater daily MEI, HP, and skin and eye temperatures than Nellore. We found significant correlations ( ≤ 0.005) between daily HP and maximum ( = 0.65) and average skin temperatures ( = 0.65) and maximum ( = 0.65) and average ocular surface ( = 0.69) temperatures recorded on d 50. Infrared thermography has potential to be used to evaluate HP in cattle.
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Bovinos/fisiología , Metabolismo Energético/fisiología , Termogénesis , Termografía , Animales , MasculinoRESUMEN
We aimed to evaluate the expression of genes related to the regulation of muscle protein turnover in the longissimus dorsi (LD) muscle of Angus and Nellore bulls and to estimate the within-breed correlations of gene expression and performance traits. Thirteen genes related to the IGF-1 and myostatin pathways were studied. Thirteen animals, with an initial average BW of 381.2 ± 11.8 kg, from each breed were used in a completely randomized 2 × 2 factorial design (2 breeds and 2 feeding levels). The diet consisted of corn silage and a corn-soybean meal concentrate in a roughage-to-concentrate ratio of 30:70. Cattle were fed ad libitum (with 9 animals from each breed) or feed restricted (a 55% restriction of total DMI of ad libitum-fed animals, calculated as percentage of metabolic BW, with 4 animals of each breed). The experimental period lasted for 82 d and it was preceded by a 28-d adaptation period. The performance traits evaluated were slaughter body weight, total ADG (from d 1 to 82 of the trial), initial ADG (from d 1 to 41 of the trial), final ADG (from d 42 to 82 of the trial), total DMI (from d 1 to 82 of the trial), initial DMI (from d 1 to 41 of the trial), final DMI (from d 42 to 82 of the trial), HCW, LD weight (LDW), and rib eye area (REA). After slaughter, samples were taken from the LD muscle between the 12th and 13th ribs for gene expression analysis by quantitative reverse transcription PCR. There was no difference ( > 0.05) in the expression of any of the genes studied between ad libitum-fed Angus and ad libitum-fed Nellore, whereas feed restriction increased the expression of (; < 0.001), (; = 0.05), and (; = 0.04) and decreased the expression of ( < 0.01). The REA was negatively correlated to (; = 0.01), (; = 0.02), and ( = 0.05). The HCW was negatively correlated to ( = 0.01) and ( = 0.01) and tended to be negatively correlated to ( = 0.07), whereas the LDW tended to be negatively correlated to ( = 0.08). The genes , , and seem to be important for muscle growth and may be worthy of further investigation as future strategies for increasing muscle in livestock.
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Composición Corporal/fisiología , Bovinos/genética , Regulación de la Expresión Génica/fisiología , Proteínas Musculares/metabolismo , Alimentación Animal/análisis , Animales , Composición Corporal/genética , Peso Corporal , Bovinos/fisiología , Dieta/veterinaria , Fibras de la Dieta/metabolismo , Conducta Alimentaria/fisiología , Factor I del Crecimiento Similar a la Insulina/metabolismo , Masculino , Proteínas Musculares/genética , Ensilaje/análisisRESUMEN
OBJECTIVES: This study evaluated both the relation between dobutamine-induced wall motion abnormalities and the physiologic and morphologic features of epicardial coronary artery stenoses and the impact of the extent of the area at risk on the sensitivity of dobutamine echocardiography. BACKGROUND: The accuracy of dobutamine echocardiography has traditionally been assessed by comparing results with stenosis geometry. Myocardial fractional flow reserve is a functional index of coronary stenosis severity that takes into account both antero-grade and collateral flow and may therefore be a more appropriate standard for comparison. METHODS: Seventy-five patients with normal left ventricular function, good echocardiographic images and an isolated coronary stenosis underwent, within 6 h, dobutamine echocardiography, quantitative coronary angiography and intracoronary pressure measurements. Myocardial fractional flow reserve was calculated as the ratio of mean hyperemic distal coronary to aortic pressure. RESULTS: The degree of dobutamine-induced dyssynergy correlated significantly with percent diameter stenosis (r = 0.68), area stenosis (r = 0.68) and minimal lumen diameter (r = -0.60) and markedly better with myocardial fractional flow reserve (r = -0.77). However, marked dispersion of the individual data was observed. The sensitivity of dobutamine echocardiography in detecting lesions with a minimal lumen diameter < or = 1 mm and diameter stenosis > or = 50% was 83% and 80%, respectively. All but one patient with a myocardial fractional flow reserve >0.75 had a normal stress test result. Among patients with a myocardial fractional flow reserve < or = 0.75, the sensitivity of dobutamine echocardiography was significantly lower for lesions in vessels with a reference diameter < or = 2.6 mm than for lesions in larger vessels (58% vs. 90%, p = 0.008). CONCLUSIONS: 1) The magnitude of wall motion abnormalities induced by dobutamine infusion correlates with angiographic and, more closely, with functional indexes of stenosis severity, even though a wide scatter is observed. 2) In patients with a functionally significant stenosis, the amount of myocardium at risk is a critical determinant of the accuracy of dobutamine echocardiography.
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Angiografía Coronaria , Enfermedad Coronaria/fisiopatología , Dobutamina , Ecocardiografía , Circulación Coronaria , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y EspecificidadRESUMEN
The MDR1 gene encodes the P-glycoprotein, an efflux transporter with broad substrate specificity. P-glycoprotein has raised great interest in pharmacogenetics because it transports a variety of structurally divergent drugs, including lipid-lowering drugs. The synonymous single-nucleotide polymorphism C3435T and the nonsynonymous single-nucleotide polymorphism G2677T/A in MDR1 have been indicated as potential determinants of variability in drug disposition and efficacy. In order to evaluate the effect of G2677T/A and C3435T MDR1 polymorphisms on serum levels of lipids before and after atorvastatin administration, 69 unrelated hypercholesterolemic individuals from São Paulo city, Brazil, were selected and treated with 10 mg atorvastatin orally once daily for four weeks. MDR1 polymorphisms were analyzed by PCR-RFLP. C3435T and G2677T polymorphisms were found to be linked. The allelic frequencies for C3435T polymorphism were 0.536 and 0.464 for the 3435C and 3435T alleles, respectively, while for G2677T/A polymorphism allele frequencies were 0.580 for the 2677G allele, 0.384 for the 2677T allele and 0.036 for the 2677A allele. There was no significant relation between atorvastatin response and MDR1 polymorphisms (repeated measures ANOVA; P > 0.05). However, haplotype analysis revealed an association between T/T carriers and higher basal serum total (TC) and LDL cholesterol levels (TC: 303 +/- 56, LDL-C: 216 +/- 57 mg/dl, respectively) compared with non-T/T carriers (TC: 278 +/- 28, LDL-C: 189 +/- 24 mg/dl; repeated measures ANOVA/Tukey test; P < 0.05). These data indicate that MDR1 polymorphism may have an important contribution to the control of basal serum cholesterol levels in Brazilian hypercholesterolemic individuals of European descent.
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Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , LDL-Colesterol/sangre , Genes MDR/genética , Haplotipos/genética , Hipercolesterolemia/genética , Adulto , Anciano , Anticolesterolemiantes/uso terapéutico , Atorvastatina , Brasil , LDL-Colesterol/genética , Femenino , Frecuencia de los Genes , Ácidos Heptanoicos/uso terapéutico , Humanos , Hipercolesterolemia/sangre , Hipercolesterolemia/tratamiento farmacológico , Hipercolesterolemia/etnología , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , Polimorfismo de Longitud del Fragmento de Restricción , Polimorfismo de Nucleótido Simple , Pirroles/uso terapéutico , Población BlancaRESUMEN
Actions and outcomes of Wisconsin dairy farms (n = 113) that completed a team-based milk quality improvement program were assessed. Selection of milk quality goals and adoption of management actions were evaluated. Management and financial data related to milk quality were compared between the beginning and end of the milk quality program. Milk quality premiums were reported to be the largest financial opportunity related to milk quality and reduction of bulk milk somatic cell count (SCC) was the most commonly listed goal. Recommended management practices were highly adopted upon completion of the program. Operators of herds housed in freestalls that were not using a recommended management practice at the beginning of the program were more likely to adopt it during the program than were operators of herds housed in stallbarns. Use of written protocols for treatment of clinical mastitis, microbiological analysis of milk obtained from cows having clinical mastitis, frequent training of milking personnel, and scheduled milking system analysis occurred more often in herds housed in freestalls. In general, herds completing the milk quality program reported significant reductions in measures of clinical and subclinical mastitis, reduced bacterial counts in bulk milk, and reduced culling of cows because of mastitis. At the end of the program, increased milk quality premiums and decreased losses attributable to mastitis resulted in improved estimates of financial performance. Herds beginning the program having high bulk milk SCC had greater improvements in milk quality during the program, including a greater reduction in bulk milk SCC and fewer losses attributable to mastitis. The majority of the herds considered themselves successful in achieving their goals for milk quality and intended to continue meeting with their teams.