RESUMO
The global aquaculture industry has grown exponentially in recent years using to control of infections and diseases, a variety of veterinary drugs (VMP) are used, including antibiotics, antifungals and antiparasitics, which have different routes of emission, environmental persistence and side effects to aquatic organisms, becoming one of the main concerns in its use of veterinary drugs (VMP) and its potential toxicological impact on the environment, in this context, Chile is considered one of the main salmon producers. Ecological risk assessment of active principles used infreshwater fish farms worldwide and in Chile were investigated. We recollect a physical - chemical properties of active principles used by fish farms and we could estimate the relative hazard a priori. Later active principles grouped as antibiotics (n = 6), antiparasitics (n = 5), anesthetics (n = 3), and disinfectants (n = 7) were assessed using a mass balance model based on fugacity was developed for each active principle under treatments via immersion and food administration in fish, while a volumetric model for disinfectants and sodium chloride was used for estimating the predicted environmental concentration (PEC), under a real smolt farming scenario in fish farms. Ecotoxicological data were collected from open literature to predict the no-effect concentration (PNEC). The ecological risk assessment was characterized using a risk quotient (RQ = PEC/PNEC) based in two assessment tiers. Results revealed that 12 active ingredients showed a high risk (RQ ≥ 1), thus indicating that adverse effects could occur and further investigation with measured concentrations in the field are required to reduce exposure in surface waters.
Assuntos
Poluentes Químicos da Água , Animais , Aquicultura , Chile , Pesqueiros , Água Doce , Medição de Risco , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidadeRESUMO
Easy, economic, precise species authentication is currently necessary in many areas of research and diagnosis in molecular biology applied to conservation studies of endangered species. Here, we present a new method for the identification of three fox species of the Lycalopex genus in Chile. We developed an assay based on high-resolution melt analysis of the mitochondrial cytochrome B gene, allowing a simple, low cost, fast, and accurate species determination. To validate the assay applicability for noninvasive samples, we collected fecal samples in the Atacama Desert, finding unexpectedly one species outside of its known distribution range. We conclude that the assay has a potential to become a valuable tool for a standardized genetic monitoring of the Lycalopex species in Chile.
RESUMO
BACKGROUND: Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, and patients with AF have a significantly increased risk for ischemic stroke. Approximately 15% of all strokes are caused by AF. The molecular basis and underlying mechanisms and pathophysiology of AF remain largely unknown. METHODS AND RESULTS: We have identified a large AF family with an autosomal recessive inheritance pattern. The AF in the family manifests with early onset at the fetal stage and is associated with neonatal sudden death and, in some cases, ventricular tachyarrhythmias and waxing and waning cardiomyopathy. Genome-wide linkage analysis was performed for 36 family members and generated a 2-point logarithm of the odds (LOD) score of 3.05 for marker D5S455. The maximum multipoint LOD score of 4.10 was obtained for 4 markers: D5S426, D5S493, D5S455, and D5S1998. Heterozygous carriers have significant prolongation of P-wave duration on ECGs compared with noncarriers (107 versus 85 ms on average; P=0.000012), but no differences between these 2 groups were detected for the PR interval, QRS complex, ST-segment duration, T-wave duration, QTc, and R-R interval (P>0.05). CONCLUSIONS: Our findings demonstrate that AF can be inherited as an autosomal recessive trait and define a novel genetic locus for AF on chromosome 5p13 (arAF1). A genetic link between AF and prolonged P-wave duration was identified. This study provides a framework for the ultimate cloning of the arAF1 gene, which will increase the understanding of the fundamental molecular mechanisms of atrial fibrillation.
Assuntos
Fibrilação Atrial/genética , Cardiomiopatias/genética , Cromossomos Humanos Par 5/genética , Morte Súbita Cardíaca/epidemiologia , Adolescente , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial/congênito , Fibrilação Atrial/epidemiologia , Cardiomiopatias/patologia , Criança , Pré-Escolar , Consanguinidade , DNA/genética , Feminino , Doenças Fetais/genética , Coração Fetal/fisiopatologia , Genes Recessivos , Genoma Humano , Genótipo , Sistema de Condução Cardíaco/fisiopatologia , Humanos , Lactente , Recém-Nascido , Escore Lod , Masculino , Pessoa de Meia-Idade , Linhagem , Taquicardia Ventricular/genética , Uruguai/epidemiologiaRESUMO
The exact nature of the mechanism of action of intrauterine devices (IUDs) is not known yet, in spite of numerous studies made to ascertain the effects of the devices. The assumption that the foreign body might induce microscopic changes capable of altering the biochemical behavior of the endometrium induced us to study the problem from the morphological viewpoint. thus, a study was performed on 20 yound IUD wearers for periods of 12 to 36 months. The IUDs used were either inert or medicated poliethylene. For this purpose, 2 mm3 samples of endometrium obtained through control biopsies were studied were studied by light microscopy and transmission (TEM) and scanning (SEM) electron microscopy. Controls were obtained from normal endometrium in either the middle or secretory stage of the cycle. The aim was to investigate ephithelial and stromal changes possibli related with the presence of inert or medicated IUDs. Light microscopy and SEM offer similar images: a flat ephithelium devoid of cilia, and areas with exfoliated epithelium, leaving the basal membrane in direct contact with the uterine cavity. An early predecidualization of the stroma is observed. Under TEM, the main changes were located in the cell organelles: decrease of microvilli, degenerative chagnes of mitochondria, vesiculation of citoplasmic membranes. In the stroma, predecidual cells and granulocytes were observed. Based on our observations it may be concluded that IUDs create unfavorable envronmental conditions for blastocystic attachment where apaprently no dislodgement of the implanted ovum occuts. Its action seems to be contraceptive rather than abortifacient in the usual sense
Assuntos
Adulto , Humanos , Feminino , Endométrio/ultraestrutura , Dispositivos Intrauterinos/efeitos adversos , Endométrio/patologiaRESUMO
The proprioceptive receptors are important nerve endings that are found mainly at musculotendinous junctions, ligaments and capsules of the articular joints. Their importance is linked with the fact that they provide the sensory-motor feedback for neurmuscular control. Therefore, more accurate inofrmation on the type, number and regenerative capacity of mechanoreceptors is of great value in traumatology. We studied the neuroanatomical structure of these receptors in cat knee ligaments, by means of metalic impregnation methods. This first communication contains our results with gold chloride. The motor end plates and neuromuscular spindles of tenuissimus muscle of the cat were employed for testing method modifications. This allowed us to reproduce results. The connective septa of collagen bundles show nerves containing 20 to 30 nerve fibers of the myelinic as well as amyelinic type; besides, free endings, branched or elongated structures resembling glomeruli, and corpuscles were observed. Free endings are very rare, and are found only next to blood vessels, whereas branched endings appear as spirals located between fat cells. Some coiled nerve fibres were observed on the surface of collagen fibers. Corpuscles of Ruffini are also presente at the connective septa. In general terms, a great variety in the structure of the receptors was observed. Our description of specific populations of nerve endings in car knee ligaments suggests that they do contribute to the afferent discharge providing information to the initiation of protective reflexs