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1.
Lett Appl Microbiol ; 75(2): 281-292, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35313037

RESUMEN

Essential oils encapsulated in a polymeric matrix can be used as an alternative method to control fungi and mycotoxins. The essential oils were extracted by hydrodistillation and characterized by gas chromatography. The nanofibres were produced from poly (acid lactic) (PLA) containing essential oils by the Solution Blow Spinning method. The antifungal and antimicotoxygenic properties were evaluated against Aspergillus ochraceus and Aspergillus westerdijkiae by the fumigation method. Terpinen-4-ol (20·23%), sabinene (20·18%), 1·8-cineole (16·69%) and γ-terpinene (11·03%) were the principal compounds present in the essential oil from Alpinia speciosa, whereas citral (97·67%) was dominant from Cymbopogon flexuosus. Microscopy images showed that the addition of essential oils caused an increase in the diameter of the nanofibres. The infrared spectroscopy results indicated the presence of essential oils in the PLA nanofibres. Differential scanning calorimetry curves also indicated the existence of interactions between the essential oils and polymeric macromolecules through their plasticizing action. The hydrophobic character of nanofibres was revealed by the contact angle technique. An antifungal effect was observed, the mycelial growths (3·25-100%) and the synthesis of ochratoxin A (25·94-100%) were inhibited by the presence of the nanofibres. The results suggest that bioactive nanofibres hold promise for application to control toxigenic fungi.


Asunto(s)
Alpinia , Cymbopogon , Nanofibras , Aceites Volátiles , Alpinia/química , Antifúngicos/farmacología , Aspergillus , Cymbopogon/química , Hongos , Aceites Volátiles/química , Aceites Volátiles/farmacología , Poliésteres
2.
Lett Appl Microbiol ; 74(5): 741-751, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35122277

RESUMEN

The extraction and characterization of the essential oils (EO) from Satureja montana L., Myristica fragrans H. and Cymbopogon flexuosus and the determination of their antibacterial and antioxidant activities were achieved. The EO were identified by gas chromatography/mass spectrometry and quantified by gas chromatography using a flame ionization detector. The antibacterial potential against Escherichia coli and Staphylococcus aureus was evaluated by cell susceptibility assays and by scanning electron microscopy. The antioxidant activity was evaluated by the 2,2-diphenyl-1-picrylhydrazyl assay, by ß-carotene bleaching and by determining the reducing power. Borneol (36·18%), γ-terpineol (12·66%) and carvacrol (11·07%) were the principal components in the EO from S. montana, and sabinene (49·23%) and α-pinene (13·81%) were found in the EO from M. fragrans. Geranial (59·66%) and neral (38·98%) isomers were the only major components in the EO from C. flexuosus. The EO from S. montana was effective against E. coli, with minimum inhibitory and bactericidal concentrations (MIC and MBC) of 6·25 µl ml-1 , whereas bactericidal potential against both was observed for the EO from M. fragrans; MIC = 6·25 µl ml-1 for S. aureus and MBC = 12·5 µl ml-1 for E. coli. A significant protective role on lipid substrates in the ß-carotene bleaching assay was seen for the EO from S. montana and M. fragrans. Overall, such EO can be promising agents against pathogenic bacteria and for protecting biomolecules during oxidative stress.


Asunto(s)
Antiinfecciosos , Cymbopogon , Myristica , Aceites Volátiles , Satureja , Antibacterianos/química , Antibacterianos/farmacología , Antiinfecciosos/farmacología , Antioxidantes/farmacología , Escherichia coli , Pruebas de Sensibilidad Microbiana , Montana , Aceites Volátiles/química , Aceites Volátiles/farmacología , Satureja/química , Staphylococcus aureus , beta Caroteno/farmacología
3.
J Food Sci Technol ; 59(12): 4685-4694, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36276518

RESUMEN

Canastra's Minas artisanal cheese [QMA (Minas artisanal cheese)] is a protected geographical indication traditional food. The influence of fungi on the cheese ripening process is of great importance. This study aimed to apply culture-dependent and -independent methods to determine the mycobiota of QMA produced in the Canastra region, as well as to determine its physicochemical characteristics. Illumina-based amplicon sequencing and matrix-assisted laser desorption ionization time-of-flight mass spectrometry were the culture-independent methods used. The physicochemical analysis results showed that the QMA has a moisture content ranging 18.4-28.2%, fat content ranging 20.5-40%, sodium chloride percentage of approximately 0.9%, and pH ranging 5.2-5.5. The population of fungi ranged between 6.3 and 8 log colony-forming unit/g. Fusarium spp., Geotrichum candidum, Paecilomyces spp., Trichosporon coremiiforme, Candida catenulata, Aspergillus spp., Trichosporon japonicum, Aspergillus oryzae, Kluyveromyces spp., Torulaspora spp., and Debaryomyces spp. were the most prevalent fungi. The methods used to evaluate the mycobiota provide a better understanding of which species are present in the final product and eventually contribute to the characteristics of QMA. Geotrichum candidum and C. catenulata were identified as promising species for future studies on product quality.

4.
J Dairy Sci ; 100(6): 4829-4838, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28434746

RESUMEN

This study compared vaginal temperature, physiologic, and productive parameters in lactating dairy cows supplemented or not with Omnigen-AF (Phibro Animal Health, Teaneck, NJ) during the summer months in a tropical environment. Thirty-two lactating, primiparous (n = 16) and multiparous (n = 16) pregnant Holstein × Gir cows were ranked by parity, days in milk, body weight, and body condition score (BCS), and assigned to receive (SUPP; n = 16) or not (CON; n = 16) Omnigen-AF (Phibro Animal Health, Teaneck, NJ) at 56 g/cow daily (as-fed basis). During the experimental period (d -6 to 56), cows were maintained in a single drylot pen with ad libitum access to water and a total mixed ration, and milked twice daily. Cows received Omnigen-AF mixed with 200 g of corn (as-fed basis) after the daily morning milking through self-locking head gates, whereas CON cows concurrently received 56 g of kaolin mixed with 200 g of corn. For feed intake evaluation, cows from both treatments were randomly divided in 4 groups of 8 cows each, and allocated to 8 individual feeding stations for 3 d. Intake was evaluated 4 times per group from d 1 to 56. From d -6 to 0, d 15 to 28, and d 43 to 56, cow vaginal temperature was recorded hourly. Environmental temperature-humidity index (THI) was also recorded hourly from d 15 to 28 and d 43 to 56. Cows were evaluated for body weight and BCS on d -6 and 56, individual milk production was recorded daily from d -6 to 56, and milk samples were collected on d -6, 0, 7, 14, 21, 28, 35, 42, 49, and 56 for analyses of somatic cell count and milk components. Blood samples were collected on d -6, -3, 0, 9, 15, 18, 21, 24, 27, 36, 45, 48, 51, 54, and 56. Results from samples or observations collected from d -6 to 0 were included as an independent covariate in each respective analysis. Environmental THI was 74.2 ± 0.5 and cows were exposed to THI >68 for 633 h within a total of 672 h of evaluation. Cows assigned to CON had greater vaginal temperature on d 28, 43, 45, and from d 48 to 55 (by 0.38 to 0.52%), as well as greater mean somatic cell count (by 97%) and serum haptoglobin concentrations (by 89%) compared with SUPP cows. Cows assigned to SUPP had greater mean dry matter intake (by 7%), BCS on d 56 (by 11%), and mean serum insulin concentrations (by 35%) compared with CON cows. Hence, SUPP ameliorated hyperthermia, improved nutritional status, and modulated systemic and mammary gland immune parameters in lactating dairy cows exposed to heat stress conditions.


Asunto(s)
Alimentación Animal , Regulación de la Temperatura Corporal/fisiología , Enfermedades de los Bovinos/fisiopatología , Trastornos de Estrés por Calor/veterinaria , Inmunomodulación , Lactancia/fisiología , Animales , Peso Corporal , Bovinos , Enfermedades de los Bovinos/sangre , Enfermedades de los Bovinos/inmunología , Dieta , Suplementos Dietéticos , Femenino , Trastornos de Estrés por Calor/sangre , Trastornos de Estrés por Calor/inmunología , Trastornos de Estrés por Calor/fisiopatología , Calor/efectos adversos , Humedad , Lactancia/inmunología , Leche/metabolismo , Paridad , Embarazo , Vagina/fisiopatología
5.
J Appl Microbiol ; 120(5): 1181-92, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26787003

RESUMEN

AIMS: This study was aimed to identify yeasts and moulds as well as to detect mycotoxin in corn silages in southern Minas Gerais, Brazil. METHODS AND RESULTS: Corn silages from 36 farms were sampled to analyse dry matter, crude protein, ether extract, ash, neutral detergent fibre, nonfibre carbohydrates and mycotoxins contents, yeasts and moulds population, pH and temperature values. The mycotoxins found in high frequency were aflatoxin in 77·7% of analysed samples, ochratoxin (33·3%) and zearalenone (22·2%). There was no significant correlation between the mycotoxin concentration and the presence of moulds. The pH was negatively correlated with ochratoxin concentration. Aspergillus fumigatus was identified in all silages that presented growth of moulds. Ten different yeast species were identified using the culture-dependent method: Candida diversa, Candida ethanolica, Candida rugosa, Issatchenkia orientalis, Kluyveromyces marxianus, Pichia manshurica, Pichia membranifaciens, Saccharomyces cerevisiae, Trichosporon asahii and Trichosporon japonicum. Another six different yeast species were identified using the culture-independent method. CONCLUSIONS: A high mycotoxin contamination rate (91·6% of the analysed silages) was observed. The results indicated that conventional culturing and PCR-DGGE should be combined to optimally describe the microbiota associated with corn silage. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides information about the corn silage fermentation dynamics and our findings are relevant to optimization of this silage fermentation.


Asunto(s)
Hongos/aislamiento & purificación , Micotoxinas/análisis , Ensilaje/análisis , Ensilaje/microbiología , Levaduras/aislamiento & purificación , Zea mays/microbiología , Brasil , Fermentación , Hongos/clasificación , Hongos/crecimiento & desarrollo , Hongos/metabolismo , Micotoxinas/metabolismo , Clima Tropical , Levaduras/genética , Levaduras/crecimiento & desarrollo , Levaduras/metabolismo , Zea mays/química
6.
Genes Immun ; 16(3): 206-12, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25569261

RESUMEN

The large variation in individual response to infection with Rift Valley fever virus (RVFV) suggests that host genetic determinants play a role in determining virus-induced disease outcomes. These genetic factors are still unknown. The systemic inoculation of mice with RVFV reproduces major pathological features of severe human disease, notably the hepatitis and encephalitis. A genome scan performed on 546 (BALB/c × MBT) F2 progeny identified three quantitative trait loci (QTLs), denoted Rvfs-1 to Rvfs-3, that were associated with disease susceptibility in MBT/Pas mice. Non-parametric interval-mapping revealed one significant and two suggestive linkages with survival time on chromosomes 2 (Rvfs-1), 5 (Rvfs-3) and 11 (Rvfs-2) with respective logarithm of odds (LOD) scores of 4.58, 2.95 and 2.99. The two-part model, combining survival time and survival/death, identified one significant linkage to Rvfs-2 and one suggestive linkage to Rvfs-1 with respective LOD scores of 5.12 and 4.55. Under a multiple model, with additive effects and sex as a covariate, the three QTLs explained 8.3% of the phenotypic variance. Sex had the strongest influence on susceptibility. The contribution of Rvfs-1, Rvfs-2 and Rvfs-3 to survival time of RVFV-infected mice was further confirmed in congenic mice.


Asunto(s)
Predisposición Genética a la Enfermedad , Fiebre del Valle del Rift/genética , Fiebre del Valle del Rift/virología , Virus de la Fiebre del Valle del Rift , Animales , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Femenino , Marcadores Genéticos , Estudio de Asociación del Genoma Completo , Haplotipos , Escala de Lod , Masculino , Ratones , Fenotipo , Polimorfismo Genético , Sitios de Carácter Cuantitativo , Fiebre del Valle del Rift/mortalidad
7.
Animal ; 18(9): 101260, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39116470

RESUMEN

In Brazil, heifers typically calve at 36-48 months. Due to the high demand for meat and the need to reduce slaughter age, high supplementation has become commonly used in beef cattle farming. However, the literature remains scarce on studies that explore the impact of grazing management during the background phase on the productivity and reproductive efficiency of young Nellore heifers. This study aimed to evaluate the effects of two-herbage allowances (HA) on forage characteristics, performance, physiology and reproductive parameters of replacement Nellore heifers. Ninety weaned heifers [169 ± 19 kg of shrunk body weight (SBW); 210 ± 28 days of age] were blocked by initial BW and randomly assigned to receive different HA: (1) High herbage allowance (HHA: 7.2 kg DM/kg BW) and (2) Low herbage allowance (LHA: 3.3 kg DM/kg BW); and divided into six paddocks, totaling 12 paddocks. The experimental period was divided into the growing phase (D173) and the reproductive season (D83). Continuous stocking with a variable stocking rate was used. The supplement was provided daily with expected intake of around 10 g/kg of BW. The HHA pasture showed greater values of canopy height, greater HA, and lower values of CP and CP: in vitro digestible DM ratio than the LHA pasture over the days of the study (P ≤ 0.05). Herbage mass and the green stem proportion were lower in LHA pasture (P < 0.01), while the green leaf (g/kg DM) and senescent stem proportions (g/kg DM) were higher (P = 0.080) when compared to HHA pasture. Heifers maintained on HHA pasture had a higher average daily gain (P < 0.01), forage intake (P < 0.003), higher SBW (P < 0.01), Longissimus area (P < 0.01), and 12th-rib fat thickness (P < 0.01) than those kept in the LHA pasture. The proportion of heifers that reached the weight at maturity on D173 (P = 0.027) and the proportion of pubertal pregnancy heifers (P = 0.042) were greatest in the HHA treatment. The blood urea nitrogen (P = 0.002) was higher in heifers maintained in the LHA pasture. Heifers maintained in HHA pasture showed higher values of relative abundance of mRNA for UGT1A6 (P = 0.004) and IGFBP3 (P = 0.072). The use of HHA criteria increased forage intake, body gain, and carcass attributes of animals, which led to better reproductive performance of Nellore heifers.


Asunto(s)
Alimentación Animal , Dieta , Suplementos Dietéticos , Reproducción , Animales , Bovinos/fisiología , Femenino , Alimentación Animal/análisis , Suplementos Dietéticos/análisis , Reproducción/efectos de los fármacos , Brasil , Dieta/veterinaria , Crianza de Animales Domésticos/métodos , Fenómenos Fisiológicos Nutricionales de los Animales/efectos de los fármacos , Distribución Aleatoria
8.
Animal ; 18(3): 101084, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38367312

RESUMEN

Procedures such as transport and marketing can subject animals to water and feed deprivation and impair animal health and performance. Maintaining the mineral status of animals under these conditions can bring benefits to health and performance. The use of hydroxychloride mineral sources can improve mineral status, nutrient digestibility and performance. Two studies were conducted to investigate how the supplementation of 02 trace mineral sources of Cu and Zn and 48-hour water/feed deprivation would affect the performance and metabolism of grass-fed beef cattle. In the first study, 20 castrated and rumen-canulated Nellore steers (BW = 350 ±â€¯132 kg; 20 m) were distributed in individual pens, in a 2 × 2 factorial arrangement: supplemental Cu and Zn sources from inorganic vs hydroxychloride (HTM) and 48-hours deprivation (WFD) vs unrestricted (WFU) access to water and feed. The 57d of study was divided into two periods: (1) Adaptation from -21d to -1d and (2) evaluation from 0d to 36d. Interaction between deprivation × period was detected (P < 0.05) for digestibility of DM (DMD), organic matter (OMD), neutral detergent fiber (NDFD), and acid detergent fiber (ADFD). Deprivation increased DMD, OMD, NDFD, and ADFD immediately after the deprivation period (3-5d), but impaired digestibility at longer periods such as 11-13d and 32-34d. DM (DMI) and nutrient intake (P = 0.075), as well as NDFD were higher in HTM. Several ruminal parameters were affected by deprivation: short-chain fatty acids concentration decreased, while rumen pH increased (deprivation × time; P < 0.05); decreased propionate, butyrate and increased isobutyrate, isovalerate, and valerate in WFD (deprivation × time; P < 0.05), respectively. In the second study, eighty-four intact Nellore males (BW = 260 ±â€¯35 kg) were blocked by BW and randomly assigned to Urochloa brizantha cv. Marandu paddocks for 131d in a 2 × 2 factorial arrangement. Liver Cu was higher in WFU/HTM animals (mineral × deprivation; P < 0.05). Interaction between deprivation × period (P < 0.05) was detected for BW and average daily gain (ADG). On 2d and 12d after deprivation, WFD increased ADG and recovered the BW lost. In conclusion, water and feed deprivation imposed in these trials were able to impact several nutrient digestibility and ruminal fermentation parameters in short- and long-term. Performance was not affected by the studied factors. Furthermore, supplementation with sources of Cu and Zn hydroxychloride increased Cu in the liver and tended to increase DMI and NDFD.


Asunto(s)
Cobre , Zinc , Masculino , Bovinos , Animales , Suplementos Dietéticos , Dieta/veterinaria , Agua/metabolismo , Detergentes/metabolismo , Digestión , Minerales/metabolismo , Fermentación , Alimentación Animal/análisis , Rumen/metabolismo
9.
Animal ; 17(4): 100770, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37031589

RESUMEN

Feedlot diets are often enriched with additives to mitigate health disorders and promote cattle performance, including the feed-grade antimicrobials monensin and tylosin. However, alternative feeding strategies are warranted given the increasing regulations regarding the use of antimicrobials in feedlot diets. This study evaluated the performance, physiological, and health responses of feedlot cattle offered a synbiotic supplement (yeast-derived prebiotic + Bacillus subtilis probiotic), which replaced or was fed in conjunction with monensin and tylosin. Angus-influenced steers (n = 192) from four different cowherds were weaned on day -1 and transported (800 km) to the feedlot. Steers were allocated to 1 of 24 pens (eight steers/pen) upon arrival on day 0. Pens were assigned to receive (n = 8/treatment) a total-mixed ration (TMR) containing: (1) monensin and tylosin (RT; 360 mg/steer daily from Rumensin and 90 mg/steer daily from Tylan; Elanco Animal Health, Greenfield, IN, USA), (2) yeast-derived ingredient and B. subtilis probiotic (CC; 18 g/steer daily of Celmanax and 28 g/steer daily of Certillus; Church and Dwight Co., Inc., Princeton, NJ, USA), or (3) a combination of RT and CC (RTCC). Steers were slaughtered according to BW in four groups balanced by treatment and pens and received treatments for 252 ± 4 days. No treatment effects were detected (P ≥ 0.17) for steer BW gain and morbidity responses. Mean TMR intake was greater and gain:feed ratio was less (P ≤ 0.01) in CC compared with RT and RTCC steers. Mean plasma leptin concentration was greater (P ≤ 0.05) in CC compared with RT and RTCC steers. Steers receiving CC had greater (P ≤ 0.04) concentrations of plasma cortisol, haptoglobin, glucose, and beta-hydroxybutyrate, and less (P ≤ 0.05) concentration of non-esterified fatty acids compared with RT and RTCC steers on day 14 of the experiment. Carcass marbling was greater (P = 0.01) in CC compared with RT steers and tended to be greater (P = 0.07) in RTCC compared with RT steers. Proportion of carcasses that graded Choice or better and Longissimus muscle area were greater (P ≤ 0.05) in CC and RTCC compared with RT steers. Incidence of liver abscesses was less (P = 0.01) in RTCC compared with CC steers and tended to be less (P = 0.09) in RT compared with CC steers. Results from this experiment indicate that the synbiotic supplement may replace monensin and tylosin without reducing steer BW gain, with potential improvements to carcass quality traits.


Asunto(s)
Antiinfecciosos , Probióticos , Bovinos , Animales , Tilosina/farmacología , Monensina/farmacología , Saccharomyces cerevisiae , Alimentación Animal/análisis , Dieta/veterinaria , Probióticos/farmacología
10.
Eur J Clin Microbiol Infect Dis ; 31(7): 1311-8, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22006011

RESUMEN

This study investigated a large population of individuals positive for A. actinomycetemcomitans and performed a two way analysis assessing the relation between the different serotypes of the bacterium and periodontal conditions. The serotypes analysis (serotypes a, b, c, d, e, f) showed that out of the 204 selected individuals positive for A. actinomycetemcomitans, 152 were positive for a single serotype, 27 showed a variable mixed infection and 25 individuals were not positive for any of the serotypes tested. Serotypes a, b and c were largely found (98%), and serotype c was the most prevalent. Serotypes d, e, and f were either not detected or relatively rare. It was also verified that in non-periodontitis individuals, serotypes a and c were more prevalent (p<0.05); in individuals with mild or moderate/severe chronic periodontitis serotype c was also more common (p<0.05); and aggressive periodontitis subjects showed high prevalence of both serotypes b and c (p<0.05). In conclusion, our study showed that serotype c was the most prevalent in both diseased and healthy subjects. Aggressive periodontitis subjects were not exclusively associated with A. actinomycetemcomitans serotype b. Non-typeable strains were either not detected or were relatively infrequent, and serotypes d and f were not detected in the examined Brazilian population.


Asunto(s)
Infecciones por Pasteurellaceae/microbiología , Infecciones por Pasteurellaceae/patología , Pasteurellaceae/clasificación , Pasteurellaceae/aislamiento & purificación , Periodontitis/microbiología , Periodontitis/patología , Adolescente , Adulto , Brasil/epidemiología , Niño , Coinfección/epidemiología , Coinfección/microbiología , Coinfección/patología , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infecciones por Pasteurellaceae/epidemiología , Periodontitis/epidemiología , Prevalencia , Serotipificación , Adulto Joven
11.
Braz J Biol ; 82: e236354, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34105666

RESUMEN

Cladocera represent an important zooplankton group because of their seasonal prominence in terms of abundance and their contribution in controlling primary production (phytoplankton). On a global scale, there are few studies on Cladocera in hypersaline environments. The present work aims to evaluate the spatio-temporal variation of the Cladocera assemblage across a salinity gradient in the habitats of the Araruama Lagoon. Samples were collected in random months over a period of four years at 12 fixed stations in the Araruama Lagoon using a WP2 plankton net equipped with a flow meter. Our results do not reveal significant influence of the tide and seasonal variation as factors affecting the Cladocera assemblage. Five Cladocera species were found in the Araruama Lagoon, only in stations 11 and 12 where they reached an average of 1,799 ± 3,103 ind. m-3. The mean of the Shannon Diversity Index was 0.45 ± 0.2. The species that stood out in terms of frequency and abundance were: Penilia avirostris (frequency of occurrence: 71%), followed by Pseudevadne tergestina (41%). The same species also stood out in terms of relative abundance, Penilia avirostris (87%) and Pseudevadne tergestina (11%). The absence of Cladocera in the innermost parts of the lagoon suggests that their entrance to these locations is possibly inhibited by the salinity and temperature gradient of the lagoon, being the main factors influencing the dynamics of the Cladocera assemblages.


Asunto(s)
Cladóceros , Animales , Fitoplancton , Plancton , Estaciones del Año , Zooplancton
12.
J Neurol Sci ; 278(1-2): 96-101, 2009 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-19162278

RESUMEN

BACKGROUND: Chagas disease cardiomyopathy is a common form of dilated cardiomyopathy worldwide, and an important cause of stroke in Latin America. The long-term cumulative risk of ischemic cerebrovascular event (ICE) and its relation to left ventricular (LV) dysfunction have not been determined. The aims of this study were to describe the incidence and to evaluate the effect of LV ejection fraction on the risk for ICE in patients with Chagas cardiomyopathy. METHODS: A total of 213 consecutive patients with Chagas disease and LV systolic dysfunction, 131 males, mean age 48+/-12 years, were prospectively enrolled. The use of anticoagulation was based on clinical indications. The end point was ICE, which included fatal or nonfatal stroke and transient ischemic attack. Risk factors for events were assessed by Cox proportional-hazards analysis. RESULTS: Mean follow-up was 36 months; 69 patients died and seven underwent cardiac transplantation. The overall incidence of ICE was 2.67 events per 100 patient/years. Independent risk factors for ICE included LV ejection fraction (HR 0.95, 95% CI 0.91 to 0.99, p=0.009) and left atrial volume corrected for body surface area (HR 1.04, 95% CI 1.01 to 1.07, p=0.007), which persisted after adjustment for anticoagulation use. Patients with ejection fractions

Asunto(s)
Isquemia Encefálica/etiología , Isquemia Encefálica/fisiopatología , Cardiomiopatía Chagásica/complicaciones , Cardiomiopatía Chagásica/fisiopatología , Factores de Edad , Cardiomiopatía Chagásica/mortalidad , Ecocardiografía , Femenino , Estudios de Seguimiento , Ventrículos Cardíacos/fisiopatología , Humanos , Estimación de Kaplan-Meier , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estudios Prospectivos , Factores de Riesgo
13.
Animal ; 13(6): 1208-1213, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30355369

RESUMEN

Excitable temperament disrupts physiological events required for reproductive development in cattle, but no research has investigated the impacts of temperament on growth and puberty attainment in Bos indicus females. Hence, this experiment evaluated the effects of temperament on growth, plasma cortisol concentrations and puberty attainment in B. indicus heifers. A total of 170 Nelore heifers, weaned 4 months before the beginning of this experiment (days 0 to 91), were managed in two groups of 82 and 88 heifers each (mean ± SE; initial BW=238±2 kg, initial age=369±1 days across groups). Heifer temperament was evaluated via exit velocity on day 0. Individual exit score was calculated within each group by dividing exit velocity into quintiles and assigning heifers with a score from 1 to 5 (1=slowest; 5=fastest heifer). Heifers were classified according to exit score as adequate (ADQ, n=96; exit score⩽3) or excitable temperament (EXC, n=74; exit score>3). Heifer BW, body condition score (BCS) and blood samples were obtained on days 0, 31, 60 and 91. Heifer exit velocity and score were recorded again on days 31, 60 and 91. Ovarian transrectal ultrasonography was performed on days 0 and 10, 31 and 41, 60 and 70, 81 and 91 for puberty evaluation. Heifer was declared pubertal at the first 10-day interval in which a corpus luteum was detected. Exit velocity and exit score obtained on day 0 were correlated (r⩾0.64, P<0.01) with evaluations on days 31, 60 and 91. During the experiment, ADQ had greater (P<0.01) mean BCS and BW gain, and less (P<0.01) mean plasma cortisol concentration compared with EXC heifers. Temperament × time interactions were detected (P<0.01) for exit velocity and exit score, which were always greater (P<0.01) in EXC v. ADQ heifers. A temperament × time interaction was also detected (P=0.03) for puberty attainment, which was delayed in EXC v. ADQ heifers. At the end of the experiment, a greater (P<0.01) proportion of ADQ were pubertal compared with EXC heifers. In summary, B. indicus heifers classified as EXC had reduced growth, increased plasma cortisol concentrations and hindered puberty attainment compared to ADQ heifers. Moreover, exit velocity may serve as temperament selection criteria to optimize development of B. indicus replacement heifers.


Asunto(s)
Bovinos/psicología , Hidrocortisona/sangre , Temperamento , Animales , Brasil , Bovinos/sangre , Bovinos/crecimiento & desarrollo , Femenino
14.
Oncogene ; 26(2): 186-97, 2007 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-16819506

RESUMEN

Methylating drugs such as temozolomide (TMZ) are widely used in the treatment of brain tumours (malignant gliomas). The mechanism of TMZ-induced glioma cell death is unknown. Here, we show that malignant glioma cells undergo apoptosis following treatment with the methylating agents N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and TMZ. Cell death determined by colony formation and apoptosis following methylation is greatly stimulated by p53. Transfection experiments with O(6)-methylguanine-DNA methyltransferase (MGMT) and depletion of MGMT by O(6)-benzylguanine showed that, in gliomas, the apoptotic signal originates from O(6)-methylguanine (O(6)MeG) and that repair of O(6)MeG by MGMT prevents apoptosis. We further demonstrate that O(6)MeG-triggered apoptosis requires Fas/CD95/Apo-1 receptor activation in p53 non-mutated glioma cells, whereas in p53 mutated gliomas the same DNA lesion triggers the mitochondrial apoptotic pathway. This occurs less effectively via Bcl-2 degradation and caspase-9, -2, -7 and -3 activation. O(6)MeG-triggered apoptosis in gliomas is a late response (occurring >120 h after treatment) that requires extensive cell proliferation. Stimulation of cell cycle progression by the Pasteurella multocida toxin promoted apoptosis whereas serum starvation attenuated it. O(6)MeG-induced apoptosis in glioma cells was preceded by the formation of DNA double-strand breaks (DSBs), as measured by gammaH2AX formation. Glioma cells mutated in DNA-PK(cs), which is involved in non-homologous end-joining, were more sensitive to TMZ-induced apoptosis, supporting the involvement of DSBs as a downstream apoptosis triggering lesion. Overall, the data demonstrate that cell death induced by TMZ in gliomas is due to apoptosis and that determinants of sensitivity of gliomas to TMZ are MGMT, p53, proliferation rate and DSB repair.


Asunto(s)
Antineoplásicos Alquilantes/farmacología , Apoptosis/efectos de los fármacos , Neoplasias Encefálicas/patología , Daño del ADN/efectos de los fármacos , Dacarbazina/análogos & derivados , Glioma/patología , Guanina/análogos & derivados , Western Blotting , Neoplasias Encefálicas/metabolismo , Caspasas/metabolismo , Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Roturas del ADN de Doble Cadena , Dacarbazina/farmacología , Proteína Ligando Fas/metabolismo , Proteína de Dominio de Muerte Asociada a Fas/metabolismo , Citometría de Flujo , Glioma/metabolismo , Guanina/metabolismo , Humanos , Metilnitronitrosoguanidina/farmacología , O(6)-Metilguanina-ADN Metiltransferasa/genética , O(6)-Metilguanina-ADN Metiltransferasa/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , ARN Interferente Pequeño/farmacología , Temozolomida , Células Tumorales Cultivadas , Ensayo de Tumor de Célula Madre , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo
15.
Braz. j. biol ; 82: e236354, 2022. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1249288

RESUMEN

Cladocera represent an important zooplankton group because of their seasonal prominence in terms of abundance and their contribution in controlling primary production (phytoplankton). On a global scale, there are few studies on Cladocera in hypersaline environments. The present work aims to evaluate the spatio-temporal variation of the Cladocera assemblage across a salinity gradient in the habitats of the Araruama Lagoon. Samples were collected in random months over a period of four years at 12 fixed stations in the Araruama Lagoon using a WP2 plankton net equipped with a flow meter. Our results do not reveal significant influence of the tide and seasonal variation as factors affecting the Cladocera assemblage. Five Cladocera species were found in the Araruama Lagoon, only in stations 11 and 12 where they reached an average of 1,799 ± 3,103 ind. m-3. The mean of the Shannon Diversity Index was 0.45 ± 0.2. The species that stood out in terms of frequency and abundance were: Penilia avirostris (frequency of occurrence: 71%), followed by Pseudevadne tergestina (41%). The same species also stood out in terms of relative abundance, Penilia avirostris (87%) and Pseudevadne tergestina (11%). The absence of Cladocera in the innermost parts of the lagoon suggests that their entrance to these locations is possibly inhibited by the salinity and temperature gradient of the lagoon, being the main factors influencing the dynamics of the Cladocera assemblages.


Os cladóceros representam um importante grupo de zooplâncton, devido ao seu destaque sazonal em termos de abundância e à sua contribuição no controlo da produção primária (fitoplâncton). Em escala global, há poucos estudos com Cladocera em ambientes hipersalinos. O presente trabalho tem como objetivo avaliar a variação espaço-temporal da assembleia de Cladocera em um gradiente de salinidades da Lagoa de Araruama. As amostras foram coletadas em meses aleatórios, durante um período de quatro anos, em 12 estações fixas na Lagoa de Araruama, utilizando uma rede de plâncton WP2 equipada com um fluxômetro. Os nossos resultados não revelam uma influência significativa da maré e da variação sazonal como fatores que afetam a assembleia de Cladocera. Cinco espécies de Cladocera foram encontradas na Lagoa de Araruama. A assembleia apresentou maior densidade absoluta estações 12 e 11, atingindo uma a média de 1.799 ± 3.103 inds-3. A média do Índice de Diversidade de Shannon foi de 0,45 ± 0,2. As espécies que se destacaram em termos de frequência e abundância foram: Penilia avirostris (frequência de ocorrência: 71%), seguida de Pseudevadne tergestina (41%). As mesmas espécies também se destacaram em termos de abundância relativa Penilia avirostris (87%) e Pseudevadne tergestina (11%). A ausência de Cladocera nas partes mais interiores da lagoa sugere que a sua entrada nestes locais é possivelmente inibida pela salinidade e gradiente de temperatura da lagoa, sendo os principais fatores que influenciam a dinâmica da assembleia de Cladocera.


Asunto(s)
Animales , Cladóceros , Fitoplancton , Plancton , Estaciones del Año , Zooplancton
16.
Braz. j. biol ; 82: 1-9, 2022. map, tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1468487

RESUMEN

Cladocera represent an important zooplankton group because of their seasonal prominence in terms of abundance and their contribution in controlling primary production (phytoplankton). On a global scale, there are few studies on Cladocera in hypersaline environments. The present work aims to evaluate the spatio-temporal variation of the Cladocera assemblage across a salinity gradient in the habitats of the Araruama Lagoon. Samples were collected in random months over a period of four years at 12 fixed stations in the Araruama Lagoon using a WP2 plankton net equipped with a flow meter. Our results do not reveal significant influence of the tide and seasonal variation as factors affecting the Cladocera assemblage. Five Cladocera species were found in the Araruama Lagoon, only in stations 11 and 12 where they reached an average of 1,799 ± 3,103 ind. m-³. The mean of the Shannon Diversity Index was 0.45 ± 0.2. The species that stood out in terms of frequency and abundance were: Penilia avirostris (frequency of occurrence: 71%), followed by Pseudevadne tergestina (41%). The same species also stood out in terms of relative abundance, Penilia avirostris (87%) and Pseudevadne tergestina (11%). The absence of Cladocera in the innermost parts of the lagoon suggests that their entrance to these locations is possibly inhibited by the salinity and temperature gradient of the lagoon, being the main factors influencing the dynamics of the Cladocera assemblages.


Os cladóceros representam um importante grupo de zooplâncton, devido ao seu destaque sazonal em termos de abundância e à sua contribuição no controlo da produção primária (fitoplâncton). Em escala global, há poucos estudos com Cladocera em ambientes hipersalinos. O presente trabalho tem como objetivo avaliar a variação espaço-temporal da assembleia de Cladocera em um gradiente de salinidades da Lagoa de Araruama. As amostras foram coletadas em meses aleatórios, durante um período de quatro anos, em 12 estações fixas na Lagoa de Araruama, utilizando uma rede de plâncton WP2 equipada com um fluxômetro. Os nossos resultados não revelam uma influência significativa da maré e da variação sazonal como fatores que afetam a assembleia de Cladocera. Cinco espécies de Cladocera foram encontradas na Lagoa de Araruama. A assembleia apresentou maior densidade absoluta estações 12 e 11, atingindo uma a média de 1.799 ± 3.103 inds-³. A média do Índice de Diversidade de Shannon foi de 0,45 ± 0,2. As espécies que se destacaram em termos de frequência e abundância foram: Penilia avirostris (frequência de ocorrência: 71%), seguida de Pseudevadne tergestina (41%). As mesmas espécies também se destacaram em termos de abundância relativa Penilia avirostris (87%) e Pseudevadne tergestina (11%). A ausência de Cladocera nas partes mais interiores da lagoa sugere que a sua entrada nestes locais é possivelmente inibida pela salinidade e gradiente de temperatura da lagoa, sendo os principais fatores que influenciam a dinâmica da assembleia de Cladocera.


Asunto(s)
Animales , Cladóceros/crecimiento & desarrollo , Agua de Mar , Análisis Espacio-Temporal
17.
Braz. j. biol ; 822022.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468674

RESUMEN

Abstract Cladocera represent an important zooplankton group because of their seasonal prominence in terms of abundance and their contribution in controlling primary production (phytoplankton). On a global scale, there are few studies on Cladocera in hypersaline environments. The present work aims to evaluate the spatio-temporal variation of the Cladocera assemblage across a salinity gradient in the habitats of the Araruama Lagoon. Samples were collected in random months over a period of four years at 12 fixed stations in the Araruama Lagoon using a WP2 plankton net equipped with a flow meter. Our results do not reveal significant influence of the tide and seasonal variation as factors affecting the Cladocera assemblage. Five Cladocera species were found in the Araruama Lagoon, only in stations 11 and 12 where they reached an average of 1,799 ± 3,103 ind. m-3. The mean of the Shannon Diversity Index was 0.45 ± 0.2. The species that stood out in terms of frequency and abundance were: Penilia avirostris (frequency of occurrence: 71%), followed by Pseudevadne tergestina (41%). The same species also stood out in terms of relative abundance, Penilia avirostris (87%) and Pseudevadne tergestina (11%). The absence of Cladocera in the innermost parts of the lagoon suggests that their entrance to these locations is possibly inhibited by the salinity and temperature gradient of the lagoon, being the main factors influencing the dynamics of the Cladocera assemblages.


Resumo Os cladóceros representam um importante grupo de zooplâncton, devido ao seu destaque sazonal em termos de abundância e à sua contribuição no controlo da produção primária (fitoplâncton). Em escala global, há poucos estudos com Cladocera em ambientes hipersalinos. O presente trabalho tem como objetivo avaliar a variação espaço-temporal da assembleia de Cladocera em um gradiente de salinidades da Lagoa de Araruama. As amostras foram coletadas em meses aleatórios, durante um período de quatro anos, em 12 estações fixas na Lagoa de Araruama, utilizando uma rede de plâncton WP2 equipada com um fluxômetro. Os nossos resultados não revelam uma influência significativa da maré e da variação sazonal como fatores que afetam a assembleia de Cladocera. Cinco espécies de Cladocera foram encontradas na Lagoa de Araruama. A assembleia apresentou maior densidade absoluta estações 12 e 11, atingindo uma a média de 1.799 ± 3.103 inds-3. A média do Índice de Diversidade de Shannon foi de 0,45 ± 0,2. As espécies que se destacaram em termos de frequência e abundância foram: Penilia avirostris (frequência de ocorrência: 71%), seguida de Pseudevadne tergestina (41%). As mesmas espécies também se destacaram em termos de abundância relativa Penilia avirostris (87%) e Pseudevadne tergestina (11%). A ausência de Cladocera nas partes mais interiores da lagoa sugere que a sua entrada nestes locais é possivelmente inibida pela salinidade e gradiente de temperatura da lagoa, sendo os principais fatores que influenciam a dinâmica da assembleia de Cladocera.

18.
Transplant Proc ; 49(4): 906-912, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28457423

RESUMEN

BACKGROUND: Vascular complications after kidney transplantation may cause allograft loss. Here, we describe 2 patients with extrarenal mycotic pseudoaneurysm after kidney transplantation. PATIENTS: Patient 1 was a 54-year-old man who developed pseudoaneurysm 60 days after transplantation, and patient 2 was a 48-year-old woman who was diagnosed with a pseudoaneurysm 5 months after transplantation. RESULTS: Patient 1 had a deceased-donor kidney transplant with end-to-side external iliac arterial anastomosis that was reconstructed 8 days after transplantation owing to rupture and major bleeding. At 60 days after transplantation, he had high serum creatinine level and Doppler ultrasonography showed a pseudoaneurysm of the arterial graft anastomosis and postanastomotic renal artery stenosis. Treatment included surgical excision of the pseudoaneurysm, vascular reconstruction, and fluconazole, with mycologic culture of the resected pseudoaneurysm showing Candida albicans. Patient 2 developed nondisabling intermittent claudication at 5 months after kidney transplantation, with a pseudoaneurysm subsequently observed on Doppler ultrasonography and computerized tomographic angiography. Treatment included renal artery thrombectomy and common iliac bypass to the hilar donor renal artery with inverted ipsilateral long saphenous vein. Operative samples showed C albicans, and she was treated with fluconazole. Both patients had satisfactory outcomes, and both kidney allografts were preserved. CONCLUSIONS: Extrarenal mycotic pseudoaneurysms after kidney transplantation require a high index of suspicion for early diagnosis, and preservation of the kidney graft may be achieved with the use of surgical treatment and antifungal therapy.


Asunto(s)
Aneurisma Falso/microbiología , Aneurisma Infectado/microbiología , Trasplante de Riñón/efectos adversos , Complicaciones Posoperatorias/microbiología , Hemorragia Posoperatoria/microbiología , Aneurisma Falso/cirugía , Aneurisma Infectado/cirugía , Candida albicans , Femenino , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/cirugía , Hemorragia Posoperatoria/cirugía , Arteria Renal/microbiología , Arteria Renal/cirugía , Trombectomía/métodos
19.
Arq. bras. med. vet. zootec. (Online) ; 73(1): 62-72, Jan.-Feb. 2021. tab
Artículo en Portugués | LILACS, VETINDEX | ID: biblio-1153037

RESUMEN

Objetivou-se com este estudo comparar a associação de detomidina e cetamina ou dextrocetamina, por via intravenosa contínua, em oito cadelas submetidas a dois protocolos: GCD - indução anestésica com 5mg/kg e infusão intravenosa contínua de 20mg/kg/h de cetamina; e GDD - indução com 3,5mg/kg e infusão de 14mg/kg/h de dextrocetamina. Associou-se detomidina, 30µg/kg/h, em ambos os grupos. Registraram-se frequência cardíaca (FC), pressão arterial (PA), frequência respiratória (f), temperatura (TC), miorrelaxamento, analgesia, hemogasometria e eletrocardiograma, antes e 15 minutos após a MPA (Mbasal e Mmpa); após o início da infusão (Mic); a cada 10 minutos até 90 minutos (M10, M20, M30, M40, M50, M60, M70, M80 e M90); e 30 minutos após o fim da infusão (M120). Foi observada bradicardia em Mmpa no GCD e de Mmpa a M10 no GDD. Ocorreu hipotensão em Mmpa e hipertensão a partir de Mic. A f diminuiu de M10 a M30. Foram observados: onda T de alta amplitude, bloqueios atrioventriculares e parada sinusal. Ocorreu acidose respiratória. O período de recuperação foi de 219,6±72,3 minutos no GCD e de 234,1±96,8 minutos no GDD. A cetamina e a dextrocetamina, associadas à detomidina por infusão contínua, causam efeitos cardiorrespiratórios e anestésicos similares.(AU)


The combination of detomidine and ketamine or dextrocetamine for continuous intravenous infusion was compared in eight female dogs submitted to two protocols: GCD - 5mg/kg of anesthetic induction and continuous intravenous infusion of ketamine 20mg/kg/h; and GDD - induction with 3.5mg/kg and infusion of 14mg/kg/h of dextrocetamine. Detomidine, 30µg/kg/h was associated in both groups. Heart rate (HR), blood pressure (BP), respiratory rate (RR), temperature (CT), myorelaxation, analgesia, blood gas analysis and electrocardiogram were recorded before and 15 minutes after MPA (Mbasal and Mmpa); after the start of infusion (Mic); every 10 minutes to 90 minutes (M10, M20, M30, M40, M50, M60, M70, M80 and M90); and 30 minutes after the end of infusion (M120). Bradycardia was observed in Mmpa in GCD and from Mmpa to M10 in GDD. There was hypotension in Mmpa and hypertension from Mic. The RR decreased from M10 to M30. High amplitude T wave, atrioventricular blocks and sinus arrest were observed. Respiratory acidosis occurred. The recovery period was 219.6±72.3 minutes in GCD and 234.1±96.8 minutes in GDD. Ketamine and S+ ketamine associated with detomidine for continuous infusion cause cardiorespiratory and similar anesthetic effects.(AU)


Asunto(s)
Animales , Femenino , Perros , N-Metilaspartato/agonistas , Agonistas alfa-Adrenérgicos/análisis , Anestésicos Combinados/análisis , Ketamina/uso terapéutico , Acidosis Respiratoria/veterinaria , Frecuencia Respiratoria , Frecuencia Cardíaca , Anestesia Intravenosa/veterinaria
20.
Cell Death Differ ; 9(10): 1099-107, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12232798

RESUMEN

Cyclobutane pyrimidine dimers (CPDs) are directly involved in signaling for UV-induced apoptosis in mammalian cells. Failure to remove these lesions, specially those located at actively expressing genes, is critical, as cells defective in transcription coupled repair have increased apoptotic levels. Thus, the blockage of RNA synthesis by lesions is an important candidate event triggering off active cell death. In this work, wild-type and XPB mutated Chinese hamster ovary (CHO) cells expressing a marsupial photolyase, that removes specifically CPDs from the damaged DNA, were generated, in order to investigate the importance of this lesion in both RNA transcription blockage and apoptotic induction. Photorepair strongly recovers RNA synthesis in wild-type CHO cell line, although the resumption of transcription is decreased in XPB deficient cells. This recovery is accompanied by the prevention of cells entering into apoptosis. These results demonstrate that marsupial photolyase has access to CPDs blocking RNA synthesis in vivo, and this may be affected by the presence of a mutated XPB protein.


Asunto(s)
Apoptosis/fisiología , Reparación del ADN/fisiología , Proteínas de Unión al ADN/deficiencia , ARN Polimerasas Dirigidas por ADN/metabolismo , Células Eucariotas/enzimología , Dímeros de Pirimidina/metabolismo , ARN/biosíntesis , Animales , Apoptosis/efectos de la radiación , Células CHO , Cricetinae , ADN Helicasas , Reparación del ADN/efectos de la radiación , Proteínas de Unión al ADN/genética , ARN Polimerasas Dirigidas por ADN/efectos de la radiación , Desoxirribodipirimidina Fotoliasa/genética , Relación Dosis-Respuesta en la Radiación , Células Eucariotas/efectos de la radiación , Mutación/genética , Dímeros de Pirimidina/antagonistas & inhibidores , ARN/genética , Rayos Ultravioleta
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