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1.
Lett Appl Microbiol ; 71(6): 645-651, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32725897

RESUMEN

Following the appearance of several antimicrobial agents to control the spread of infections, two major challenges have emerged: (i) the occurrence and blowout of multiresistant bacteria and the increase of chronic diseases and (ii) difficult-to-eradicate infections. In this study, we tested five benzoylthiourea derivatives for their ability to inhibit and stop bacterial growth and evaluated the possible influence of 1,2,4-triazolyl-benzoylthiourea derivative 4 on the formation and eradication of Staphylococcus aureus biofilms. Benzoylthiourea derivatives 4, 6, 10, 11 and 13 were obtained in one or two steps with low cost and subjected to tests to identify their minimum inhibitory concentration (MIC) and minimum bactericidal concentration. In vitro tests were also performed to assess their effects on biofilm formation and in preformed biofilms and scanning electron microscopy was used to visualize the effects on biofilm formation. The 1,2,4-triazolyl-benzoylthiourea derivative 4 showed bacteriostatic activity against the S. aureus HU25 clinical strain with an MIC of 16 µg ml-1 , which is below the toxic concentration (at 2500 µg ml-1 , 62·25% of the cells remained viable). Compound 4 also effectively prevented biofilm formation at the three subinhibitory concentrations tested (1/2 MIC, 1/4 MIC and 1/8 MIC) as confirmed by scanning electron microscopy. For breakdown of formed biofilms, the main influence was at a subinhibitory concentration (1/2 MIC). These findings make compound 4 a strong candidate for studies on the development of new antimicrobial and antibiofilm agents.


Asunto(s)
Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Tiourea/farmacología , Antibacterianos/síntesis química , Antibacterianos/química , Humanos , Pruebas de Sensibilidad Microbiana , Plancton/efectos de los fármacos , Plancton/crecimiento & desarrollo , Plancton/fisiología , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/crecimiento & desarrollo , Staphylococcus aureus/fisiología , Tiourea/química
2.
J Dairy Sci ; 103(5): 4100-4108, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32197850

RESUMEN

Staphylococcus aureus is one of the main causative agents of food poisoning. This bacterium is an important component of cheese microbiota and plays an important role in foodborne diseases. Another important component of the microbiota is the lactic acid bacterium, which actively participates in processes that define the physicochemical, sensorial, and microbiological features of cheese. Of the various microbiological interactions in cheese, the interaction between lactic acid bacteria and Staph. aureus is most relevant. To this end, we evaluated the viability of Staph. aureus strains and the expression of their enterotoxins in cheeses produced experimentally, using Weissella paramesenteroides GIR16L4 or Lactobacillus rhamnosus D1 or both as starter cultures. Over 7 d, we observed that the presence of lactic acid bacteria did not impair Staph. aureus growth. However, via qPCR we observed a change in the gene expression of staphylococcal enterotoxins, suggesting that molecular communication exists between Staph. aureus strains and lactic acid bacteria in cheese.


Asunto(s)
Toxinas Bacterianas/metabolismo , Queso/microbiología , Enterotoxinas/metabolismo , Lacticaseibacillus rhamnosus/crecimiento & desarrollo , Staphylococcus aureus/crecimiento & desarrollo , Superantígenos/metabolismo , Weissella/crecimiento & desarrollo , Animales , Toxinas Bacterianas/genética , Queso/análisis , Enterotoxinas/genética , Microbiología de Alimentos , Lactobacillales/metabolismo , Lacticaseibacillus rhamnosus/metabolismo , Leche , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismo , Superantígenos/genética , Transcriptoma , Weissella/metabolismo
3.
J Dairy Sci ; 99(8): 6086-6096, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27289151

RESUMEN

Minas artisanal cheese, produced in the Campo das Vertentes region of Brazil, is made from raw milk and endogenous starter cultures. Although this cheese is of great historical and socioeconomic importance, little information is available about its microbiological and physical-chemical qualities, or about its beneficial microbiota. This work was aimed at evaluating the qualities of the cheese and the components used for its production, comparing samples collected during the dry and rainy seasons. We also conducted molecular identification and isolated 50 samples of lactic acid bacteria from cheese (n=21), water (n=3), raw milk (n=9), and endogenous starter culture (n=17). The microbiological quality of the cheese, water, raw milk, and endogenous starter culture was lower during the rainy period, given the higher counts of coagulase-positive Staphylococcus and total and thermotolerant coliforms. Enterococcus faecalis was the lactic acid bacteria isolated most frequently (42.86%) in cheese samples, followed by Lactococcus lactis (28.57%) and Lactobacillus plantarum (14.29%). Lactobacillus brevis (5.88%), Enterococcus pseudoavium (5.88%), Enterococcus durans (5.88%), and Aerococcus viridans (5.88%) were isolated from endogenous starter cultures and are described for the first time in the literature. The lactic acid bacteria identified in the analyzed cheeses may inhibit undesirable microbiota and contribute to the safety and flavor of the cheese, but this needs to be evaluated in future research.


Asunto(s)
Queso/microbiología , Lactobacillales/aislamiento & purificación , Leche/microbiología , Estaciones del Año , Microbiología del Agua , Animales , Brasil , Queso/análisis , Enterococcus/aislamiento & purificación , Microbiología de Alimentos , Ácido Láctico , Lactobacillaceae/aislamiento & purificación , Lactobacillus plantarum/aislamiento & purificación , Lactococcus lactis/aislamiento & purificación , Microbiota , Lluvia , Agua
4.
Clin Exp Obstet Gynecol ; 39(3): 303-6, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23157029

RESUMEN

PURPOSE: The aim of this study was to evaluate the passage of fetal red blood cells to the maternal circulation, after invasive obstetric procedures, through the Kleihauer-Betke test, flow cytometry and by measurement of maternal serum alpha-fetoprotein level. METHODS: This prospective descriptive study with patients submitted to amniocentesis, cordocentesis, chorionic villus sampling (CVS), amnioreduction and ventriculoamniotic shunt was performed for karyotype analysis, treatment of hydrocephalus and polyhydramnios and to assess fetal lung maturity. Maternal blood samples were collected before and 60 minutes after the invasive obstetric procedure to search for fetal erythrocytes using the Kleihauer-Betke test, flow cytometry and serum alpha-fetoprotein measurement. RESULTS: Ten invasive obstetric procedures were performed. The mean age of the patients was 29.2 years and the mean gestational age was 29.6 weeks. The procedures were: five amniocenteses, two cordocenteses, one CVS, one ventriculo-amniotic shunt and one amnioreduction with cephalocentesis. The indications for the procedures were: karyotype analysis in five patients, fetal lung maturity assessment in two patients, amnioreduction in one patient, fetal hydrocephalus shunt in one patient and polyhydramnios related to hydranencephaly in one patient. Regarding the path of puncture, three procedures were accomplished through the placenta and seven apart from it. All punctures were successful at the first attempt. There was no significant increase of fetal erythrocyte quantity in maternal blood samples using the Kleihauer-Betke test. After cordocentesis, a significant increase of fetal erythrocytes was detected by flow cytometry and serum alpha-fetoprotein measurement. CONCLUSION: Invasive obstetric procedures during prenatal care are safe when performed by experienced professionals using adequate techniques, with minimal chance of passage of fetal erythrocytes from the fetal compartment.


Asunto(s)
Transfusión Fetomaterna/diagnóstico , Citometría de Flujo , Diagnóstico Prenatal/efectos adversos , alfa-Fetoproteínas/análisis , Adulto , Amniocentesis , Muestra de la Vellosidad Coriónica , Cordocentesis , Eritrocitos , Femenino , Sangre Fetal/citología , Enfermedades Fetales/cirugía , Hemoglobina Fetal/análisis , Transfusión Fetomaterna/etiología , Humanos , Hidrocefalia/cirugía , Cariotipificación , Embarazo , Estudios Prospectivos
5.
Parasite Immunol ; 32(4): 245-51, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20398224

RESUMEN

The aim of this study was to evaluate a possible synergism between melatonin and meloxicam in up-regulating the immune response in male Wistar rats infected with Trypanosoma cruzi during immunosuppression phenomenon, which characterizes the acute phase of the Chagas' disease. Male Wistar rats were infected with the Y strain of T. cruzi. Experiments were performed on 7, 14 and 21 days post-infection. Several immunological parameters were evaluated including gamma-interferon (IFN-gamma), interleukin-2 (IL-2), nitric oxide (NO) and prostaglandin E(2) (PGE(2)). The combined treatment with melatonin and meloxicam significantly enhanced the release of IL-2 and INF-gamma into animals' serum, when compared with the infected control groups during the course of infection. Furthermore, the blockade of PGE(2) synthesis and the increased release of NO by macrophage cells from T. cruzi-infected animals contributed to regulate the production of Th1 subset cytokines significantly reducing the parasitaemia in animals treated with the combination of both substances. Therefore, our results suggest that the association of melatonin and meloxicam was more effective in protecting animals against the harmful actions of T. cruzi infection as compared with the treatments of meloxicam or melatonin alone.


Asunto(s)
Enfermedad de Chagas/tratamiento farmacológico , Enfermedad de Chagas/inmunología , Factores Inmunológicos/uso terapéutico , Melatonina/uso terapéutico , Tiazinas/uso terapéutico , Tiazoles/uso terapéutico , Trypanosoma cruzi/inmunología , Animales , Dinoprostona/metabolismo , Sinergismo Farmacológico , Interferón gamma/sangre , Interleucina-2/sangre , Macrófagos/metabolismo , Masculino , Meloxicam , Óxido Nítrico/metabolismo , Ratas , Ratas Wistar
6.
Case Rep Nephrol ; 2020: 4079098, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32963856

RESUMEN

Introduction. Central pontine myelinolysis is characterized by the occurrence of acute demyelinating lesions of cells in the pons secondary to abrupt oscillations of serum osmolarity. Its exact incidence is not well defined, but studies show a prevalence of 0.25 to 0.5% in the general population, 2.5% in the intensive care unit, and up to 10% in patients with risk factors, such as chronic liver disease and hepatic transplantation, alcoholism, malnutrition, diuretic therapy, electrolyte imbalance, hypoglycemia, and hyperglycemia. Case Report. A 70-year-old white female with extranodal diffuse large B-cell non-Hodgkin's lymphoma (extensive mass on the left anterior chest wall), stage IVA, developed pontine myelinolysis secondary to hypovolemic acute hypernatremia, which occurred due to diarrhea caused by chemotherapy (rituximab, cyclophosphamide, doxorubicin, and vincristine). Discussion. Pontine myelinolysis occurs most often due to the rapid correction of chronic hyponatremia. But here, we describe a case of the disease secondary to the occurrence of hypovolemic acute hypernatremia in a patient with a hematological malignancy under treatment, who was on chronic treatment with thiazide diuretics and who presented with other electrolyte disturbances as risk factors for the development of pontine myelinolysis.

7.
Prev Vet Med ; 182: 105091, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32683190

RESUMEN

This study aimed to measure the impact of productivity and the consequent economic losses related to lung lesions caused by M. hyopneumoniae. Five-hundred 75 days-old pigs were selected and weighed at the beginning and at the end of the finishing phase to assess the average daily gain (ADG). These animals were evaluated at the slaughter, and samples were collected for laboratory analysis to confirm the presence of M. hyopneumoniae DNA. The lungs of each pig were examined and classified into groups based on the extension of macroscopic lung lesions. Four-hundred eighty-six lungs were examined and 68.5% (n = 333) had macroscopic lung lesions. All pigs with lesions were positive for M. hyopneumoniae in qPCR. Linear mixed regression models (proc Glimmix) were performed on SAS to estimate the effect of macroscopic lung lesion scores on the ADG of finishing pigs. All pairwise comparisons among lesion score groups were performed using p < 0.05. For each increase of one percent in the lesion area, there was a decrease of 1.8 g in the daily weight gain. All the groups had a numerically lower ADG when compared to Group 1 (no lesions). The economic analysis was performed by simulation on Excel to estimate and compare the financial performance of the different lung lesion score groups. The negative correlation found between the group with no lung lesions and the group with more than 15.1% of lesions, showed a statistical difference in ADG, which could mean an opportunity to gain up to $ 6.55 per pig at slaughter. The presence of lesions causes the animals to decrease their productive potential, causing financial loss and generating impacts on the production system.


Asunto(s)
Crianza de Animales Domésticos/economía , Pulmón/patología , Mycoplasma hyopneumoniae/fisiología , Neumonía Porcina por Mycoplasma/patología , Sus scrofa/fisiología , Animales , Femenino , Masculino , Neumonía Porcina por Mycoplasma/economía , Neumonía Porcina por Mycoplasma/fisiopatología , Neumonía Porcina por Mycoplasma/virología , Porcinos
8.
Infect Genet Evol ; 85: 104421, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32580027

RESUMEN

Crab-eating (Cerdocyon thous) and Pampas foxes (Lycalopex gymnocercus) are wild canids distributed in South America. Domestic dogs (Canis lupus familiaris) and wild canids may share viral pathogens, including rabies virus (RABV), canine distemper virus (CDV), and canine parvovirus 2 (CPV-2). To characterize the virome of these wild canid species, the present work evaluated the spleen and mesenteric lymph node virome of 17 crab-eating and five Pampas foxes using high-throughput sequencing (HTS). Organ samples were pooled and sequenced using an Illumina MiSeq platform. Additional PCR analyses were performed to identify the frequencies and host origin for each virus detected by HTS. Sequences more closely related to the Paramyxoviridae, Parvoviridae and Anelloviridae families were detected, as well as circular Rep-encoding single-stranded (CRESS) DNA viruses. CDV was found only in crab-eating foxes, whereas CPV-2 was found in both canid species; both viruses were closely related to sequences reported in domestic dogs from southern Brazil. Moreover, the present work reported the detection of canine bocavirus (CBoV) strains that were genetically divergent from CBoV-1 and 2 lineages. Finally, we also characterized CRESS DNA viruses and anelloviruses with marked diversity. The results of this study contribute to the body of knowledge regarding wild canid viruses that can potentially be shared with domestic canids or other species.


Asunto(s)
Perros/virología , Zorros/virología , Viroma , Virus/clasificación , Virus/genética , Anelloviridae/clasificación , Anelloviridae/genética , Animales , Bocavirus/clasificación , Bocavirus/genética , Brasil , Virus ADN/clasificación , Virus ADN/genética , ADN Viral , Virus del Moquillo Canino/clasificación , Virus del Moquillo Canino/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Ganglios Linfáticos/virología , Metagenómica , Paramyxoviridae/clasificación , Paramyxoviridae/genética , Parvoviridae/clasificación , Parvoviridae/genética , Parvovirus Canino/clasificación , Parvovirus Canino/genética , Filogenia , ARN Viral , Bazo/virología , Uruguay , Virosis/veterinaria , Virosis/virología , Virus/aislamiento & purificación
9.
J Int Med Res ; 37(6): 1937-51, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-20146894

RESUMEN

Ankle sprains are common acute soft-tissue injuries. This 7-day open-label, multicentre, randomized study compared the efficacy and safety of celecoxib with non-selective non-steroidal anti-inflammatory drugs (NSAIDs) in treating acute ankle sprain with moderate-to-severe ankle pain in 278 patients. Patients received either celecoxib (400 mg loading dose followed by 200 mg twice daily) or standard doses of non-selective NSAIDs. The primary endpoint was a change in the patient's assessment of ankle pain on a 0 mm (no pain) - 100 mm (worst possible pain) visual analogue scale (VAS) at day 3 compared with baseline. From a baseline of 73 mm, mean VAS pain scores decreased to 29 and 32 mm in the celecoxib and non-selective NSAID groups, respectively. The lower limit of the 95% confidence interval for the treatment difference with regard to change from baseline was greater than the pre-established non-inferiority margin of -10 mm. Using an initial loading dose, celecoxib was at least as efficacious as non-selective NSAIDs in treating acute pain due to ankle sprain.


Asunto(s)
Traumatismos del Tobillo/complicaciones , Inhibidores de la Ciclooxigenasa 2/efectos adversos , Dolor/tratamiento farmacológico , Dolor/etiología , Pirazoles/efectos adversos , Pirazoles/uso terapéutico , Esguinces y Distensiones/complicaciones , Sulfonamidas/efectos adversos , Sulfonamidas/uso terapéutico , Enfermedad Aguda , Antiinflamatorios no Esteroideos/administración & dosificación , Antiinflamatorios no Esteroideos/efectos adversos , Antiinflamatorios no Esteroideos/uso terapéutico , Celecoxib , Inhibidores de la Ciclooxigenasa 2/administración & dosificación , Inhibidores de la Ciclooxigenasa 2/uso terapéutico , Demografía , Relación Dosis-Respuesta a Droga , Determinación de Punto Final , Humanos , América Latina , Medio Oriente , Evaluación de Resultado en la Atención de Salud , Pirazoles/administración & dosificación , Sulfonamidas/administración & dosificación , Resultado del Tratamiento
10.
Prev Vet Med ; 171: 104748, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31470290

RESUMEN

A study was conducted on 21 pig herds using one-site production system in the southeast region of Brazil to assess the relationships among serological results for primary pathogens involved in respiratory diseases (Actinobacillus pleuropneumoniae, App; Mycoplasma hyopneumoniae, Mhyo; and swine influenza virus, SIV), cough index, pneumonia index, pleuritis and herd characteristics. The prevalence of antibodies against Mhyo and SIV increased throughout the raising phases, with the highest prevalence in slaughtered pigs (> 40%), while pigs in 65% (14/21) of nurseries demonstrated marked seroprevalence of App that decreased until the day of slaughter. Pleuritis and pulmonary consolidations were recorded in 9.0 and 72.4%, respectively, of the 908 evaluated lungs. Histopathological analysis of the lung lesions revealed suppurative bronchopneumonia in almost half of the lungs (48.9%). Regression analyses were conducted to identify risk factors associated with the cough index; pleuritis; pulmonary consolidation; and App, Mhyo and SIV serological results. All-in-all-out management in nursery buildings reduced the seroprevalence of Mhyo in herds. App seroprevalence was associated with pleuritis, and the presence of cough episodes in growing pigs was associated with SIV seropositivity in nursery pigs.


Asunto(s)
Infecciones por Actinobacillus/veterinaria , Infecciones por Orthomyxoviridae/veterinaria , Pleuresia/veterinaria , Enfermedades de los Porcinos/epidemiología , Enfermedades de los Porcinos/microbiología , Infecciones por Actinobacillus/epidemiología , Infecciones por Actinobacillus/patología , Actinobacillus pleuropneumoniae/aislamiento & purificación , Crianza de Animales Domésticos , Animales , Anticuerpos Antibacterianos/sangre , Anticuerpos Antivirales/sangre , Brasil/epidemiología , Tos/microbiología , Tos/veterinaria , Estudios Transversales , Granjas , Modelos Logísticos , Pulmón/patología , Mycoplasma hyopneumoniae/aislamiento & purificación , Infecciones por Orthomyxoviridae/epidemiología , Pleuresia/epidemiología , Pleuresia/microbiología , Pleuresia/patología , Neumonía Porcina por Mycoplasma/epidemiología , Análisis de Regresión , Factores de Riesgo , Estudios Seroepidemiológicos , Porcinos , Enfermedades de los Porcinos/patología , Enfermedades de los Porcinos/prevención & control
11.
Transbound Emerg Dis ; 65(2): e339-e343, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29144025

RESUMEN

Atypical porcine pestivirus (APPV) has recently been identified as a cause of congenital tremor (CT) in pigs and has been detected in semen and preputial swabs from boars that were known to be clinically affected with CT. Accordingly, the objectives of this study were to 1) detect the presence of APPV in semen, preputial fluids and preputial swabs from adult boars by quantitative reverse transcription PCR (qRT-PCR) and 2) genetically characterize a subset of positive samples to better understand the ecology of APPV in commercial boar studs and the potential risk of transmission of APPV via semen. A total of 597 samples of semen, preputial fluid and preputial swabs each representing a different boar were obtained from four commercial boar studs located in three different states in the United States. Viral RNA was detected by qRT-PCR in 90 samples (15.08%; 90/597), with the greatest per cent positive from preputial swabs (23.81%; 5/21) followed by preputial fluid (22.81%; 26/114) and semen (12.91%; 59/457). The mean cycle quantification (Cq) between sample types was similar while eleven semen samples had Cq values lower than 27.0 corresponding to approximately 2 × 106  copies/ml. Based on phylogenetic analysis of the Npro gene, different viral strains can be on the same farm at the same and different times. This is the first report of detection of APPV in semen from commercial boar studs. Studies investigating the role of semen in the transmission of APPV and production of CT are needed.


Asunto(s)
Infecciones por Pestivirus/veterinaria , Pestivirus/aislamiento & purificación , Semen/virología , Enfermedades de los Porcinos/virología , Animales , Masculino , Infecciones por Pestivirus/diagnóstico , Infecciones por Pestivirus/virología , Filogenia , ARN Viral/genética , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Porcinos , Enfermedades de los Porcinos/diagnóstico , Estados Unidos
12.
Transbound Emerg Dis ; 65(2): 375-380, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29393592

RESUMEN

Atypical porcine pestivirus (APPV) has been detected in piglets with congenital tremor (CT) from three different continents including North America, Europe and Asia. Thirteen piglets from four farms in two different states in Brazil with CT were sampled. Viral RNA was detected by quantitative real-time PCR in the cerebellum or cerebellum and spinal cord in the 100% of the piglets with CT, and APPV was not detected in any tissue sample from clinically non-affected piglets with the exception of the cerebellum of one piglet from Farm A. Piglets with CT had an odds ratio of 99.0 (95% CI 3.4, 2823.8; p = .0072) compared to piglets without CT to test positive for APPV by qRT-PCR. A subset of positive samples was selected for sequencing of the NS3 gene. Phylogenetic analysis revealed that Brazilian sequences of the NS3 formed an independent cluster and had the highest sequence identity with a sequence from the United States. This is the first identification of APPV infection in piglets with CT in South America.


Asunto(s)
Animales Lactantes/virología , Sistema Nervioso Central/virología , Infecciones por Pestivirus/veterinaria , Pestivirus/aislamiento & purificación , Enfermedades de los Porcinos/diagnóstico , Temblor/veterinaria , Animales , Brasil/epidemiología , Femenino , Masculino , Pestivirus/genética , Pestivirus/inmunología , Infecciones por Pestivirus/diagnóstico , Infecciones por Pestivirus/epidemiología , Infecciones por Pestivirus/virología , Filogenia , ARN Viral/genética , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Porcinos , Enfermedades de los Porcinos/epidemiología , Enfermedades de los Porcinos/virología , Temblor/diagnóstico , Temblor/epidemiología , Temblor/virología
13.
Neotrop Entomol ; 46(2): 151-158, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27909952

RESUMEN

The aquatic insect community is an important element for stream functionality and diversity, but the effects of altitude and conservation areas on the aquatic insect community have been poorly explored in neotropical ecozone. The lack of studies about the relative importance of space and environment on community structure is another obstacle within aquatic insect ecology, which precludes the inclusion of these studies in more current frameworks, like the metacommunity dynamics. We evaluated the relationship between the aquatic insect community structure at 19 streams in the Brazilian Cerrado and spatial and environmental variables, namely geographical distance among sites, stream altitude, chemical variables, and environmental protection areas. We partitioned the variance explained by spatial and environmental components using a partial redundancy analysis. The environment exhibited a strong spatial structure for abundance and number of genera, increasing these community parameters with elevated water conductivity. Only community composition had a large unexplained portion of variance, with a small portion constrained by environmental (altitude and conductivity) and spatial factors. A relevant point in the result was the streams with high conductivity were located outside of the conservation areas. These results suggest that the relationship between number of genera and abundance with environmental conditions is always associated with spatial configuration of streams. Our study shows that altitude is an important determinant of community structure, as it exerts indirect influences, and electrical conductivity directly determines community composition, and that some national parks may be inefficient in maintaining the diversity of aquatic insects in the Cerrado region.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Insectos , Ríos , Altitud , Animales , Brasil , Ecosistema
14.
Anim Reprod Sci ; 182: 48-55, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28522314

RESUMEN

The aim of this study was to examine the association between antral follicular blood flow velocity and the response of ewes to hormonal ovarian superstimulation. Ten Santa Inês ewes were subjected to a short- (7days; Group 1) or long-term (13days; Group 2) progesterone (CIDR®; InterAg, Hamilton, New Zealand) priming, and a superovulatory treatment with porcine follicle-stimulating hormone (pFSH; Folltropin®-V; Bioniche Animal Health, Belleville, ON, Canada), given twice daily for four consecutive days in decreasing doses and initiated four or ten days after CIDR insertion, respectively. Embryos were recovered surgically seven days after the last pFSH dose. From one day prior to until the end of the pFSH regimen (Days -1 to 3), all ewes underwent daily transrectal ultrasonography of ovaries. The number of high-velocity pixels (HVPs; 0.055-0.11m/s or upper 50% of recordable velocities) on Day 1 correlated directly with the number of corpora lutea (CL; r=0.92, P=0.0002) and of viable embryos (r=0.77, P=0.01). Correlations were also recorded between the number of HVPs on Day 3 and the recovery rate (r=-0.69, P=0.03), viability rate (r=-0.64, P=0.05), and percentage of degenerated embryos (r=0.65, P=0.04). The percentage of HVPs relative to the total area of ovarian cross section on Day 1 was correlated with the number of CL (r=0.95, P<0.001) and of viable embryos (r=0.85, P=0.002). This parameter on Day 3 was also correlated with the recovery rate (r=-0.69, P=0.03). The percentage of HVPs relative to the total Doppler area on Day 0 was correlated with the recovery rate (r=0.72, P=0.02). It can be concluded that sonographic assessment of high-velocity antral follicular blood flow has the makings of a useful non-invasive method to predict the outcome of the superovulatory treatment in ewes.


Asunto(s)
Velocidad del Flujo Sanguíneo/fisiología , Hormona Folículo Estimulante/farmacología , Folículo Ovárico/irrigación sanguínea , Ovinos/fisiología , Superovulación/efectos de los fármacos , Animales , Relación Dosis-Respuesta a Droga , Embrión de Mamíferos , Sincronización del Estro , Femenino , Hormona Folículo Estimulante/administración & dosificación , Folículo Ovárico/efectos de los fármacos , Progesterona/administración & dosificación , Progesterona/farmacología , Superovulación/fisiología , Recolección de Tejidos y Órganos
15.
Braz J Biol ; 66(2B): 611-22, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16906293

RESUMEN

The influence of environmental factors on the distribution of Ephemeroptera, Plecoptera and Trichoptera (EPT) immatures was investigated in streams of the Brazilian Center-West (Serra do Pireneus, Pirenópolis, State of Goiás). The insects were sampled by lifting the stones in front of a sieve (0.5 mm mesh) and then removing the insects from both the stone and the sieve. Sampling was carried out for 1 h at 5 collection sites over a period of 14 months. Air and water temperature (degrees C), water velocity (m/s), discharge (m(3)/s), electric conductivity (microS/cm), pH, and rainfall (mm) were also recorded. In general, we may state that altitude, hydrologic classification (order) and vegetation cover were the most important factors explaining the distribution of Ephemeroptera, Plecoptera and Trichoptera immatures. The influence of the rainfall on the temporal variation of the abundance of insects was stronger in stream segments of medium order (3rd, 4th order) compared to smaller streams (first order).


Asunto(s)
Ecosistema , Insectos/clasificación , Animales , Brasil , Densidad de Población , Dinámica Poblacional , Ríos , Estaciones del Año
16.
Neotrop Entomol ; 45(2): 159-69, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26830433

RESUMEN

Stream ecology studies see to understand ecological dynamics in lotic systems. The characterization of streams into Functional Process Zones (FPZ) has been currently debated in stream ecology because aquatic communities respond to functional processes of river segments. Therefore, we tested if different functional process zones have different number of genera and trophic structure using the aquatic insect community of Neotropical streams. We also assessed whether using physical and chemical variables may complement the approach of using FPZ to model communities of aquatic insects in Cerrado streams. This study was conducted in 101 streams or rivers from the central region of the state of Goiás, Brazil. We grouped the streams into six FPZ associated to size of the river system, presence of riparian forest, and riverbed heterogeneity. We used Bayesian models to compare number of genera and relative frequency of the feeding groups between FPZs. Streams classified in different FPZs had a different number of genera, and the largest and best preserved rivers had an average of four additional genera. Trophic structure exhibited low variability among FPZs, with little difference both in the number of genera and in abundance. Using functional process zones in Cerrado streams yielded good results for Ephemeroptera, Plecoptera, and Trichoptera communities. Thus, species distribution and community structure in the river basin account for functional processes and not necessarily for the position of the community along a longitudinal dimension of the lotic system.


Asunto(s)
Ecosistema , Insectos/clasificación , Ríos , Animales , Teorema de Bayes , Brasil , Ephemeroptera , Clima Tropical
17.
Anim Reprod Sci ; 174: 80-86, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27765297

RESUMEN

This study was conducted to document the pattern of antral follicular wave emergence throughout the 14-day, progesterone (P4)-based estrous synchronization protocol in ewes that were maintained in subtropical conditions, during the period of increasing day lengths (ID), decreasing day lengths (DD), and the transitional period (TP). In addition, the influence of ovarian status (i.e., size of ovarian antral follicles and the presence of corpora lutea) at the outset of P4 treatment on ensuing ovarian follicular wave development was examined. Sexually mature Santa Inês ewes (n=70) were subjected to one of the two estrous synchronization protocols in the three seasons. On Day 0, the ewes received an i.m. injection of prostaglandin F2α and an intravaginal P4-releasing device that remained in place for 14days (G-1CIDR) or was replaced on Day 7 (G-2CIDR). Daily ultrasonography of ovaries was conducted from Days 0 to 15. Mean (±SEM) numbers of follicular waves per ewe were 3.7±0.1 and 3.6±0.1 for G-1CIDR and G-2CIDR (P>0.05). The number of emerging follicular waves was greater (P<0.05) during the ID period than during the TP and DD periods (4.0±0.1, 3.4±0.1 and 3.6±0.1, respectively). The presence of medium-sized antral follicles (4.0 to 5.75mm) in the absence of corpora lutea at the time of CIDR insertion tended to advance follicular wave emergence. Although the long-term P4 treatment was not originally designed to synchronize follicular waves, there was a distinctive pattern of follicular wave dynamics during the period of application of CIDRs that was affected mainly by the number of emerging follicular waves and ovarian status at CIDR insertion.


Asunto(s)
Sincronización del Estro/efectos de los fármacos , Folículo Ovárico/efectos de los fármacos , Folículo Ovárico/fisiología , Ovinos/fisiología , Animales , Femenino , Fotoperiodo , Progesterona/sangre , Estaciones del Año
18.
Theriogenology ; 85(3): 452-60, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26474683

RESUMEN

This study set out to investigate the efficiency of long-term estrus synchronization protocols and ovulatory follicle dynamics in ultrasonographically monitored Santa Inês ewes during lengthening (LD; September-October) and shortening photoperiods (SD; April-May), and the transitional period (TP; January). In addition, the influence of ovarian status (e.g., size of antral follicles and/or presence of corpora lutea) at the outset of the estrus synchronization protocols on the ensuing development of ovulatory follicles was examined. Seventy sexually mature Santa Inês ewes were subjected to one of the two estrus synchronization regimens; on Day 0 (random day of the estrous cycle or anovulatory period), the ewes were fitted with an intravaginal progesterone (P4)-releasing (controlled intrauterine drug release [CIDR]) device, which was left in place for 14 days (G-1CIDR, n = 35) or replaced on Day 7 (G-2CIDR, n = 35), and received an intramuscular injection of 10 mg of PGF2α. The ewes allocated to the G-1CIDR group had mean serum P4 concentrations less than 2 ng/mL during the last 4 days of the synchronization protocol. There were no differences (P > 0.05) in mean ovulation rates between the two protocols tested nor among the ewes varying in ovarian status or studied at different times of the year, but ovulations occurred ∼ 12 hours later in the TP compared with the SD period (P < 0.05). Ovulatory follicles emerged earlier (P < 0.05) in the G-1CIDR group than in the G-2CIDR group (Day 8.3 ± 0.5 vs. 9.2 ± 0.4) and during LD (Day 7.1 ± 0.6) compared with the TP (Day 9.1 ± 0.6) and SD (Day 9.9 ± 0.5 of the protocol). In conclusion, the replacement of CIDR devices prevented the occurrence of lower-than-normal luteal phase levels of P4 at the end of the 14-day estrus synchronization protocol. However, although this procedure and seasonal influences altered certain growth characteristics of ovulatory follicles, there were no effects of these factors on the mean ovulation rate.


Asunto(s)
Sincronización del Estro/métodos , Folículo Ovárico/crecimiento & desarrollo , Ovario/fisiología , Progesterona/administración & dosificación , Estaciones del Año , Ovinos/fisiología , Administración Intravaginal , Animales , Clima , Cuerpo Lúteo/diagnóstico por imagen , Dinoprost/administración & dosificación , Ciclo Estral , Femenino , Ovario/diagnóstico por imagen , Fotoperiodo , Progesterona/sangre , Factores de Tiempo , Ultrasonografía
19.
J Am Coll Cardiol ; 22(2): 376-80, 1993 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8335807

RESUMEN

OBJECTIVES: The objective of this study was to obtain preliminary data on the relative clinical utility of direct coronary angioplasty compared with that of intravenous thrombolytic therapy for patients with acute myocardial infarction. BACKGROUND: The relative merits of intravenous thrombolytic therapy and direct coronary angioplasty as treatment for acute myocardial infarction are incompletely understood, and randomized trials of these treatments have been extremely limited. METHODS: One hundred patients with ST segment elevation presenting to a single high volume interventional center within 6 h of the onset of chest pain were randomized to receive either streptokinase (1.2 million U intravenously over 1 h) or immediate catheterization and direct coronary angioplasty. Patients were excluded for age > or = 75 years, prior bypass surgery, Q wave infarction in the region of ischemia or excessive risk of bleeding. All patients were then treated with aspirin (325 mg orally/day) and heparin (1,000 U intravenously/h) for 48 h until catheterization was performed to determine the primary study end point, namely, infarct-related artery patency at 48 h. Secondary end points were in-hospital death, left ventricular ejection fraction at 48 h and time to treatment. RESULTS: There was no difference in the baseline characteristics of the two treatment groups. Overall patient age was 56 +/- 10 years, 83% of patients were male, 11% had prior infarction, 40% had anterior infarction and 97% were in Killip class I or II. Although time to treatment was delayed in the angioplasty group (238 +/- 112 vs. 179 +/- 98 min, p = 0.005), there was no difference in 48-h infarct-related artery patency or left ventricular ejection fraction (patency 74% vs. 80%; ejection fraction 59 +/- 13% vs. 57 +/- 13%; angioplasty vs. streptokinase, p = NS for both). There were no major bleeding events, and the mortality rate with angioplasty (6%) and streptokinase (2%) did not differ (p = NS). CONCLUSIONS: These results suggest that intravenous thrombolytic therapy might be preferred over coronary angioplasty for most patients because of the often shorter time to treatment.


Asunto(s)
Angioplastia Coronaria con Balón , Infarto del Miocardio/terapia , Estreptoquinasa/uso terapéutico , Terapia Trombolítica , Anciano , Femenino , Humanos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Infarto del Miocardio/tratamiento farmacológico , Infarto del Miocardio/fisiopatología , Recurrencia , Estreptoquinasa/administración & dosificación , Volumen Sistólico , Resultado del Tratamiento , Grado de Desobstrucción Vascular
20.
Braz J Biol ; 65(1): 19-24, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16025899

RESUMEN

The relationship between the aquatic macrophyte cover in upper segments of tributaries and this cover in these tributaries but near the reservoir's main body was tested. Sixteen taxa belonging to 12 families of aquatic macrophytes were recorded in Cachoeira Dourada Reservoir. The most frequent species were Eichhornia azurea (frequency of occurrence=92%; n=37 sites) and E. crassipes (44%). Upper segments of the tributaries were the main areas colonized by these aquatic macrophytes. The positive relationship between the aquatic macrophyte cover between the upper and lower segments of tributaries indicates the importance of dispersion in the colonization of the arms and the reservoir's main body.


Asunto(s)
Agua Dulce , Plantas/clasificación , Biomasa , Brasil
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