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1.
J Dairy Sci ; 107(7): 4394-4408, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38278300

RESUMO

Our objectives were to determine the effects of reducing dietary CP concentration on nutrient digestibility, rumen function, N balance, and serum AA concentration for dairy cows in late lactation. At the initiation of the experimental period, we stratified Holstein cows (n = 128; mean ± SD 224 ± 54 DIM) by parity and days pregnant (86 ± 25 d) and assigned them to 1 of 16 pens. For 3 wk, all cows received a covariate diet containing 16.9% CP (DM basis). For the subsequent 12 wk, we assigned pens to 1 of 4 treatments containing 16.2%, 14.4%, 13.4%, or 11.9% CP (DM basis) in a randomized complete block design. Diets were fed as a TMR once daily. To reduce dietary CP, we replaced soybean meal with soybean hulls in the concentrate mix (DM basis). Diet evaluations suggested that several EAA, especially His, limited productivity as dietary CP declined. Digestibility of DM and CP decreased linearly with dietary CP reduction. Digestibility of NDF and potentially digestible NDF tended to respond in a quadratic pattern with the greatest digestibility at intermediate treatments. The reduction in dietary CP did not affect ruminal pH, but ruminal ammonia-N and branched-chain VFA concentrations declined linearly. The concentration of milk urea-N and plasma urea-N, secretion of milk N, and excretions of fecal N, urinary N, urinary urea-N, and unaccounted N decreased linearly with the reduction in dietary CP concentration. Urinary N expressed as a percentage of N intake was unaffected by dietary CP. Serum concentrations of total essential AA and NEAA were unaffected by dietary CP concentration. However, the ratio of essential to NEAA decreased with decreasing dietary CP. Serum 3-methylhistidine concentration increased linearly with decreasing dietary CP concentration, indicating greater skeletal muscle breakdown. Although our trial confirmed that reducing dietary CP decreased absolute excretion of urinary N, diet evaluations suggested that milk protein production decreased as certain essential AA became increasingly limited. Thus, reduced-CP diets have the potential to lessen reactive-N outputs of late-lactation cows, but more research is needed to design diets that minimize deleterious effects on productivity.


Assuntos
Ração Animal , Dieta , Proteínas Alimentares , Digestão , Lactação , Nitrogênio , Animais , Bovinos/metabolismo , Feminino , Nitrogênio/metabolismo , Nitrogênio/urina , Dieta/veterinária , Proteínas Alimentares/metabolismo , Rúmen/metabolismo , Leite/metabolismo , Leite/química
2.
J Endocrinol Invest ; 46(2): 381-391, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36057045

RESUMO

PURPOSE: To evaluate the impact of the "Search and rescue" field military training exercise (SR_FTX) on hormonal modulation and identify their possible correlation with physical and cognitive performance. METHODS: An observational (before and after) study was carried out, with male firefighters cadets (n = 42; age = 23[22;27] years) undergoing a nine-day military exercise (SR_FTX). The Countermovement jump (physical performance), the Stroop test (cognitive alertness), and blood tests for testosterone, cortisol, GH, and IGF-1 were applied. Wilcoxon for paired samples and Spearman's correlation tests were used. RESULTS: Testosterone (751.10 [559.10;882.8] vs. 108.40 [80.12;156.40] ng/dL) and IGF-1 (217.5 [180;239.30] vs. 105 [93;129] ng/mL) significantly decreased while GH (0.10 [0.06;0.18] vs. 1.10 [0.58;2.28] ng/mL) and cortisol (9.60 [8.20;11.55] vs. 15.55 [12.28;18.98] ug/dL) significantly increased. Physical performance (31.2 [30.04;35.4] vs. 21.49 [19,02;23,59] cm) and cognitive alertness were significantly worse after SR_FTX (Congruent task: 1,78 (0183) vs. 1,56 (0185) response/s and incongruous task: 1,23 (0191) vs. 1,02 (0207) response/s). The physical performance showed a strong correlation with testosterone (rho = 0.694) and regular correlations with both IGF-1 (rho = 0.598) and cortisol (rho = - 0.580). The Stroop test presented weak correlations with GH (rho = - 0.350) and cortisol (rho = - 0.361). CONCLUSION: SR_FTX negatively impacted hormonal modulation, physical and cognitive performance. These findings could help commanders decide to replace the employed firefighters in a real mission more frequently. Also, if the real scenario allows, they could think about providing better work conditions, such as improving caloric intake and rest periods, to preserve the military performance and health.


Assuntos
Bombeiros , Militares , Humanos , Masculino , Adulto Jovem , Adulto , Fator de Crescimento Insulin-Like I , Hidrocortisona , Exercício Físico , Sono , Testosterona
3.
Microb Pathog ; 144: 104127, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32169485

RESUMO

Despite the main strategy to overcome bacterial resistance has focused on the development of more potent antimicrobial agents, the evolutionary pressure caused by such drugs makes this strategy limited. Molecules that interfere with virulence factors appear as a promising alternative though, as they cause reduced selective pressure. As a matter of fact, staphyloxanthin biosynthesis inhibition (STXBI) has been pursued as promising strategy to reduce S. aureus virulence. Herein, we report the inhibitory profile of 27 tetrangomycin derivatives over staphyloxanthin production. The experimental result showed that naphthoquinone dehydro-α-lapachone (25 - EC50 = 57.29 ± 1.15 µM) and 2-Isopropylnaphtho[2,3-b]furan-4,9-dione (26 EC50 = 82.10 ± 1.09 µM) are the most potent compounds and suggest that hydrogen acceptor groups and lipophilic moieties decorating the naphthoquinone ring are crucial for STXBI. In addition, we present an in situ analysis, through RAMAN spectroscopy, that is inexpensive and might be employed to probe the mechanism of action of staphyloxanthin biosynthesis inhibitors. Therefore, our molecular simplification strategies afforded promising lead compounds for the development of drugs that modulate S. aureus staphyloxanthin biosynthesis.


Assuntos
Antibacterianos/farmacologia , Naftoquinonas/farmacologia , Staphylococcus aureus/metabolismo , Xantofilas/metabolismo , Benzo(a)Antracenos/química , Benzo(a)Antracenos/farmacologia , Farmacorresistência Bacteriana Múltipla , Naftalenos/química , Naftalenos/farmacologia , Naftoquinonas/química , Staphylococcus aureus/efeitos dos fármacos , Relação Estrutura-Atividade , Fatores de Virulência/antagonistas & inibidores , Fatores de Virulência/biossíntese
4.
J Dairy Sci ; 102(2): 1601-1607, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30471912

RESUMO

Our objectives were to assess the relationships between milk urea N (MUN), serum urea N (SUN), urine N (UN), and urinary urea N (UUN) in late-lactation cows fed N-limiting diets and compare these relationships with those previously established. Data were from a pen-based study in which 128 Holstein cows had been assigned to 1 of 16 pens in a randomized complete block design to assess the effects of diets containing 16.2, 14.4, 13.1, and 11.8% crude protein (CP, dry matter basis) during a 12-wk period. At least half of the cows in each pen were randomly selected to collect pen-level samples of serum and urine in wk 3, 7, and 11, when wk in lactation averaged 35, 39, and 43, respectively. A mixed model was developed to study the relationship of MUN with SUN, UN, and UUN. Week of lactation did not affect the relation between MUN and SUN across dietary treatments. However, we found a week × MUN interaction, suggesting that between wk 35 and 43 of lactation, UN excretion decreased from 89 to 73 g/d (-17 g/d) when MUN was 6.0 mg/dL (11.8% dietary CP) but increased from 142 to 149 g/d (+7 g/d) when MUN was 13.3 mg/dL (16.2% dietary CP). These effects were essentially due to changes in UUN excretion, which declined from 54 to 37 g/d (-17 g/d) and increased from 112 to 117 g/d (+5 g/d) when MUN was 6.0 and 13.3 mg/dL, respectively. When MUN was 11.2 mg/dL (15% dietary CP), UN and UUN excretions remained constant over time. Based on root mean squared prediction error and the concordance correlation coefficient, these data did not conform to most previously published prediction equations because of both mean and slope biases. The discrepancy could have resulted from difference in study design (cow vs. pen as experimental unit), dietary treatments (energy vs. N-limiting diets), frequency of measurement and duration of adaptation period (single measurement after 1 to 3 wk of adaptation vs. repeated measurements over a 12-wk period), method for determining urine volume (total collection vs. spot sampling), and the assay used to measure MUN. However, our data captured changes in kidney physiology that warrant further studies of long-term renal adaptation to N-limiting diets.


Assuntos
Bovinos/metabolismo , Dieta/veterinária , Leite/química , Nitrogênio/metabolismo , Animais , Nitrogênio da Ureia Sanguínea , Bovinos/urina , Feminino , Lactação , Nitrogênio/urina , Ureia/análise , Ureia/urina
5.
J Dairy Sci ; 100(7): 5434-5448, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28501404

RESUMO

The objectives of this study were to measure performance responses and to evaluate indictors of N utilization in late-lactation cows fed diets with incremental reductions in crude protein (CP) concentration. Holstein cows (n = 128; 224 ± 54 d in milk) were stratified by parity and days pregnant (86 ± 25 d) and randomly assigned to 1 of 16 pens in a randomized complete block design. For 3 wk, all cows received a covariate diet containing 16.9% CP [dry matter (DM) basis]. For the subsequent 12 wk, pens were randomly assigned to 1 of 4 treatments that contained 16.2, 14.4, 13.1, or 11.8% CP (DM basis). Diets were offered once daily and contained 32.5% corn silage, 32.5% alfalfa silage, 13.5% high-moisture corn, and 21.5% concentrate mix. A reduction in dietary CP was achieved by replacing soybean meal with soy hulls in the concentrate mix (DM basis). Dry matter intake, milk urea N (MUN; mg/dL), and the yield of milk urea N (g/d) decreased linearly with dietary CP. Compared with a 16.2% CP diet, a 14.4% CP diet did not alter milk yield throughout the study, but the 13.1 and 11.8% CP diets reduced milk yield after 4 and 1 wk, respectively. Furthermore, milk protein percentage was reduced for all dietary CP less than 16.2%, but this negative effect was temporary and disappeared after 7 wk for the 14.4% CP diet. In contrast, MUN adjusted to a new steady state within 1 wk for all dietary treatments. Modeling quadratic responses with a plateau led to predictions of no reduction in fat- and protein-corrected milk (32.6 kg/d) and yields of fat (1.31 kg/d), lactose (1.49 kg/d), and true protein (1.12 kg/d) until dietary CP decreased below 15.5, 15.3, 15.9, and 16.2%, respectively. In this study, MUN and the yield of MUN were highly correlated with N intake, milk protein yield, and fat- and protein-corrected milk. Surprisingly, N use efficiency (milk protein N/intake N) was not correlated with any variables related to N utilization and reached an apparent upper limit of approximately 30%. Although this observation may be associated with feeding diets deficient in metabolizable protein, late-lactation cows in this study adjusted to low dietary CP concentration better than anticipated as milk production was 2.6, 3.6, 6.4, and 8.0 kg/d higher than National Research Council (2001)-predicted metabolizable protein-allowable milk for dietary CP of 16.2, 14.4, 13.1, and 11.8%, respectively.


Assuntos
Dieta/veterinária , Proteínas Alimentares/farmacologia , Lactação , Nitrogênio/metabolismo , Silagem , Fenômenos Fisiológicos da Nutrição Animal , Animais , Bovinos , Proteínas Alimentares/administração & dosagem , Feminino , Leite/química , Paridade , Gravidez , Distribuição Aleatória , Rúmen , Zea mays
6.
Eur J Clin Microbiol Infect Dis ; 31(7): 1647-52, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22278291

RESUMO

To determine the profiles of susceptibility to antifungal and the genotypes of clinical isolates of Cryptococcus in Bahia, Brazil, 62 isolates were collected from cases of meningitis in the period from 2006 to 2010. Their susceptibilities to fluconazole, itraconazole, amphotericin B and 5-flucytosine were determined by the broth microdilution technique described by the Clinical and Laboratory Standards Institute and genotyping of the URA5 gene was accomplished by restriction fragment length polymorphism. C. neoformans accounted for 79% of the identified yeast and C. gattii represented the remaining 21%. Evaluation of the genotypes determined that 100% of the C. gattii isolates belong to the VGII genotype, and 98% of the C. neoformans isolates belong to the VNI genotype. Determination of susceptibility revealed isolates resistant to fluconazole (4.8%), 5-flucytosine (1.6%) and amphotericin B (3.2%); the stratification of sensitivity results for each species showed significant differences in susceptibility to azoles. This study is the first to describe the susceptibility profiles of molecular and clinical isolates of Cryptococcus in Bahia, Brazil. The high percentage of C. gattii isolates belonging to the VGII genotype and its lower susceptibility to antifungal agents highlight the importance of knowing which species are involved in cryptococcal infections in northeastern Brazil.


Assuntos
Antifúngicos/farmacologia , Criptococose/epidemiologia , Criptococose/microbiologia , Cryptococcus gattii/isolamento & purificação , Cryptococcus neoformans/isolamento & purificação , Tipagem Molecular , Técnicas de Tipagem Micológica , Brasil/epidemiologia , Cryptococcus gattii/classificação , Cryptococcus gattii/efeitos dos fármacos , Cryptococcus gattii/genética , Cryptococcus neoformans/classificação , Cryptococcus neoformans/efeitos dos fármacos , Cryptococcus neoformans/genética , DNA Fúngico/genética , Proteínas Fúngicas/genética , Genótipo , Humanos , Testes de Sensibilidade Microbiana , Polimorfismo de Fragmento de Restrição
7.
Avian Dis ; 66(1): 69-73, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35191645

RESUMO

The objectives of this study were to evaluate whether a preinfection of Eimeria adenoeides (EAD) or Eimeria tenella (ET) could affect the severity of subsequent histomoniasis in turkeys (Experiment 1) and if previous exposure to EAD infection, when a single or multiple inoculations of EAD were administered with sufficient time for complete cecal recovery, would affect the severity of HM incidence and lesions (Experiment 2). In Experiment 1, 200 poults were assigned to 1 of 5 groups, as follows: unchallenged negative control, positive challenge control inoculated with 105 HM, EAD at 500 oocysts/bird and Histomonas meleagridis (HM), EAD at 2500 oocysts/bird and HM, or ET at 9 × 106 oocysts/bird and HM. ET and EAD were inoculated on day 15 and HM on day 20. In Experiment 2, the trial consisted of two different challenge ages to evaluate short- or long-term EAD effects before HM challenge. Poults (n = 260) were assigned to either early-HM-challenged groups (HM on day 19 challenge control or EAD at 2500 oocysts/bird on day 14 with HM on day 19) or late-HM-challenged groups (HM on day 35 challenge control, EAD at 2500 oocysts/bird on day 14 and HM on day 35, or EAD at 100 oocysts/bird every 2-3 days during the first 3 weeks and HM on day 35). An unchallenged negative-control group was used for both the early- and late-challenge phases in Experiment 2. Mortalities were recorded, and surviving poults were scored for histomoniasis-related hepatic and cecal lesions. In Experiment 1, preinfection with both doses of EAD reduced the mortality as well as the cecal and hepatic lesions caused by histomoniasis. In Experiment 2, neither short- nor long-term preinfection with EAD had an effect on histomoniasis-related mortality or lesions. Differences between Experiments 1 and 2 may be due to the level of infection caused by the prechallenge with EAD and the resulting destruction of cecal tissue.


Evaluación de la preinfección por Eimeria adenoeides sobre la severidad de la histomoniasis en pavos. Los objetivos de este estudio fueron evaluar si una preinfección por Eimeria adenoeides (EAD) o Eimeria tenella (ET) podría afectar la severidad de la histomoniasis subsequente en pavos (Experimento 1); y si la exposición previa a la infección por E. adenoeides, cuando se administraron una o varias inoculaciones de E. adenoeides con tiempo suficiente para la completa recuperación cecal, afectaría la gravedad de la incidencia y las lesiones de Histomonas meleagridis (Experimento 2). En el Experimento 1, se asignaron 200 pavipollos en cinco grupos, de la siguiente manera: control negativo no desafiado, control de desafío positivo inoculado con 105 de H. meleagridis, un grupo con E. adenoeides a 500 ooquistes/ave e H. meleagridis (HM), otro grupo con E. adenoeides a 2500 ooquistes/ave y H. meleagridis, o E. tenella a 9×106 ooquistes/ave y H. meleagridis. Se inocularon E. tenella y E. adenoeides el día 15 y H. meleagridis el día 20. En el Experimento 2, el ensayo consistió en dos edades de exposición diferentes para evaluar los efectos de E. adenoeides a corto o largo plazo antes del desafío con H. meleagridis. Los pavipollos (n = 260) se asignaron a los grupos de desafío temprano con H. meleagridis (H. meleagridis en el día 19 en el grupo control de desafío o E. adenoeides con 2500 ooquistes/ave el día 14 y con H. meleagridis en el día 19) o los grupos de desafío tardío con H. meleagridis (H. meleagridis en el día 35 del control de desafío, E. adenoeides a 2,500 ooquistes/ave el día 14 y H. meleagridis en el día 35, o E. adenoeides con 100 ooquistes/ave cada 2-3 días durante las primeras 3 semanas y H. meleagridis en el día 35). En el Experimento 2, se utilizó un grupo de control negativo no desafiado para ambas fases de exposición temprana y tardía. Se registraron la mortalidad y los pavipollos supervivientes se asignaron puntuaciones en cuanto a lesiones hepáticas y cecales relacionadas con histomoniasis. En el Experimento 1, la preinfección con ambas dosis de E. adenoeides redujo la mortalidad, así como las lesiones cecales y hepáticas causadas por histomoniasis. En el Experimento 2, ni la preinfección a corto ni a largo plazo con E. adenoeides tuvo un efecto sobre la mortalidad o las lesiones relacionadas con la histomoniasis. Las diferencias entre los Experimentos 1 y 2 pueden deberse al nivel de infección causado por el desafío previo con E. adenoeides y la destrucción resultante del tejido cecal.


Assuntos
Coccidiose , Eimeria tenella , Eimeria , Doenças das Aves Domésticas , Infecções por Protozoários , Trichomonadida , Animais , Coccidiose/veterinária , Oocistos , Perus
8.
Poult Sci ; 101(3): 101656, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35016048

RESUMO

Repeated serial in vitro passage of Histomonas meleagridis, the etiological agent of histomoniasis (blackhead) of turkeys, was demonstrated to markedly achieve attenuation and reduction of virulence as compared to the original wild-type isolate. Four experiments were performed to evaluate the route (oral vs. intracloacal) and age (day-of-hatch vs. d 14) for administration of attenuated H. meleagridis isolates as vaccine candidates against homologous or heterologous wild-type challenge. Attenuated H. meleagridis were developed from 2 different strains (Buford strain originating in Georgia; PHL2017 strain originating in Northwest Arkansas). Buford P80a (passage 80, assigned as isolate lineage "a" following repeated passage) was selected as the primary vaccine candidate and was evaluated in Experiments 1-3. Experiment 4 evaluated selected candidates of attenuated PHL2017 (P67, P129) and Buford (P80a, P200a, P138b, P198c) strains against Buford wild-type challenge. As has been demonstrated previously, wild-type H. meleagridis cultures administered orally after 1 day of age were not infective in the current studies, but infection with wild-type cultures could be induced orally at day-of-hatch. Infection was effectively achieved via the intracloacal route at day-of-hatch and in older turkeys (d 21, d 28-29, d 35). Intracloacal inoculation of turkeys with the attenuated passaged isolates as vaccine candidates at d 14 was shown to produce significant (P < 0.05) protection from mortality, reduction in body weight gain, as well as reduction in hepatic and cecal lesions in these experiments following challenge with either the homologous wild-type isolate or from a wild-type strain obtained years later from a geographically disparate area of the United States. Inoculation with the attenuated H. meleagridis isolates at day-of-hatch, either orally or cloacally, did not produce significant protection against subsequent wild-type challenge. While offering significant protection with minimal vaccine-related negative effects, the protection from cloacal vaccine administration was neither significantly robust nor encouraging for industry application using the methods evaluated in the present manuscript since mortalities and lesions were not completely reduced which could thereby potentially allow transmission from residual infection and shedding within a flock.


Assuntos
Doenças das Aves Domésticas , Infecções Protozoárias em Animais , Vacinas Protozoárias , Trichomonadida , Animais , Galinhas , Doenças das Aves Domésticas/prevenção & controle , Infecções Protozoárias em Animais/prevenção & controle , Perus
9.
Poult Sci ; 99(4): 1978-1982, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32241479

RESUMO

Histomoniasis, caused by the protozoan parasite Histomonas meleagridis, is a disease to which turkeys are especially susceptible. Currently, no chemoprophylaxis compounds are available to mitigate this disease. Boric acid (BA) exhibits antifungal, antiseptic, and antiviral properties and has been used in the treatment of yeast infections. Based on these characteristics, an experiment was conducted to evaluate whether BA might be an efficacious prophylaxis against challenge with wild-type H. meleagridis (WTH). On day-of-hatch, poults were randomly assigned to either a basal control diet or a BA diet (basal diet + 0.2% BA). Groups consisted of a nonchallenged control (NC; basal diet), 0.2% BA + challenge (BA; 0.2% BA diet), and a positive-challenged control (PC; basal diet). On day 21, challenged groups were intracloacally inoculated with 2 × 105 WTH cells/turkey, and lesions were evaluated on day 14 postchallenge. Individual body weights were recorded on day 0, 21, and 35 to calculate the prechallenge and postchallenge body weight gain (BWG). The BA group resulted in lower prechallenge day 0 to day 21 BWG (P = 0.0001) than the NC group. Postchallenge day 21 to day 35, BWG was also lower (P = 0.0503) in the BA group than the PC group. No differences between the BA and PC groups were detected for mortalities associated with histomoniasis. Moreover, liver and cecal lesions were not statistically different between the BA and PC groups. Taken together, these data suggest that BA was not efficacious in the prevention or reduction of histomoniasis disease severity when provided at 0.2% dietary concentration under these experimental conditions.


Assuntos
Antiparasitários/farmacologia , Ácidos Bóricos/farmacologia , Doenças das Aves Domésticas/prevenção & controle , Infecções Protozoárias em Animais/prevenção & controle , Trichomonadida/efeitos dos fármacos , Perus , Animais , Quimioprevenção/veterinária , Feminino , Doenças das Aves Domésticas/parasitologia , Infecções Protozoárias em Animais/parasitologia
10.
Poult Sci ; 99(4): 1983-1987, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32241480

RESUMO

Histomoniasis is currently a re-emerging disease of major significance for many commercial turkey and broiler breeder production companies because of the unavailability of drugs or vaccines. The protozoa Histomonas meleagridis (HM) requires the presence of enteric microflora to promote the disease. The objectives of this research note were to evaluate the effect of dietary administration of sodium chlorate (SC) and sodium nitrate (SN) in vitro and in vivo for HM prophylaxis in poults. A total of 128 day-of-hatch female poults obtained from a commercial hatchery were wing-tagged and randomly assigned into 1 of 4 experimental groups: negative control (NC), positive control, dietary inclusion of SC (3,200 ppm) and SN (500 ppm). Poults from groups SC and SN started on their respective diets on day 12. All groups, except the NC, were challenged with 2 × 105 HM on day 19. Controls were fed a basal diet, identical to the treatment diets but not supplemented with SC or SN. Body weight gain (BWG) was determined weekly, starting on day 1 until day 28, and postchallenge morbidity and mortality were recorded. On day 28 of age, all surviving poults were lesion scored for hepatic and cecal lesions. Ceca and distal ileum were collected on day 28 for bacterial recovery on selective media for total aerobic, lactic acid bacteria, or gram-negative bacteria. The addition of SC and SN in the in vitro growth of HM greatly reduced the growth of the protozoa after 20 h of incubation when compared with the control nontreated group (P < 0.05). However, dietary supplementation of SC and SN had no effect against HM in vivo, as was demonstrated by BWG, the severity of lesions in the liver and ceca or bacterial recovery of treated poults when compared with the positive control group.


Assuntos
Antibioticoprofilaxia/veterinária , Antiprotozoários/metabolismo , Cloratos/metabolismo , Nitratos/metabolismo , Doenças das Aves Domésticas/prevenção & controle , Infecções Protozoárias em Animais/prevenção & controle , Perus , Ração Animal/análise , Animais , Antiprotozoários/administração & dosagem , Cloratos/administração & dosagem , Dieta/veterinária , Suplementos Nutricionais/análise , Nitratos/administração & dosagem , Doenças das Aves Domésticas/parasitologia , Infecções Protozoárias em Animais/parasitologia , Trichomonadida/efeitos dos fármacos
11.
J Microencapsul ; 26(8): 684-91, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19888877

RESUMO

Zanthoxylum tingoassuiba essential oil (EO) is a complex mixture of organic compounds among which methyl-N-methylanthranilate and sesquiterpene alcohol alpha-bisabolol represent the main compounds. The essential oil antimicrobial activity was studied against bacteria and fungi cells by diffusion disk method and significant activity was observed against S. aureus, S. aureus isolated multi-resistant and the dermathophyte fungi. Essential oil from Zanthoxylum tingoassuiba loaded into DPPC multilamellar liposomes (MLV) was successfully produced through a thin film hydration method with mean diameter of 9.37 +/- 4.69 microm. The EO-loaded liposomes showed adequate sphericity and narrower size distribution than empty liposomes. Results also showed that Zanthoxylum tingoassuiba essential oil can be incorporated in appreciable amounts (43.7 +/- 6.0%) in the prepared vesicular dispersions. A strong interaction between essential oil and lipid bilayer was indicated by a significant decrease in T(m) of the EO-loaded liposomes related to empty vesicles. Essential oil showed incomplete release profile from liposomes, suggesting that EO-loaded liposomes will be useful in pharmaceutical applications to enhance essential oil targeting to cells.


Assuntos
Anti-Infecciosos/administração & dosagem , Portadores de Fármacos/química , Lipossomos/química , Óleos Voláteis/administração & dosagem , Zanthoxylum/química , 1,2-Dipalmitoilfosfatidilcolina , Óleos Voláteis/farmacologia , Staphylococcaceae/efeitos dos fármacos
12.
Br J Pharmacol ; 154(7): 1400-13, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18552866

RESUMO

The zebrafish is a well-established model organism used in developmental biology. In the last decade, this technology has been extended to the generation of high-value knowledge on safety risks of novel drugs. Indeed, the larval zebrafish appear to combine advantages of whole organism phenotypic assays and those (rapid production of results with minimal resource engagement) of in vitro high-throughput screening techniques. Thus, if appropriately evaluated, it can offer undeniable advantages in drug discovery for identification of target and off-target effects. Here, we review some applications of zebrafish to identify potential safety liabilities, particularly before lead/candidate selection. For instance, zebrafish cardiovascular system can be used to reveal decreases in heart rate and atrial-ventricular dissociation, which may signal human ether-a-go-go-related gene (hERG) channel blockade. Another main area of interest is the CNS, where zebrafish behavioural assays have been and are further being developed into screening platforms for assessment of locomotor activity, convulsant and proconvulsant liability, cognitive impairment, drug dependence potential and impaired visual and auditory functions. Zebrafish also offer interesting possibilities for evaluating effects on bone density and gastrointestinal function. Furthermore, available knowledge of the renal system in larval zebrafish can allow identification of potential safety issues of drug candidates on this often neglected area in early development platforms. Although additional validation is certainly needed, the zebrafish is emerging as a versatile in vivo animal model to identify off-target effects that need investigation and further clarification early in the drug discovery process to reduce the current, high degree of attrition in development.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Modelos Animais , Peixe-Zebra , Animais , Sistemas de Liberação de Medicamentos , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos/métodos , Larva/metabolismo , Farmacologia/métodos
13.
Int J Cardiol ; 37(1): 7-13, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1428291

RESUMO

Seven female patients (age 27 to 53 yr) with significant mitral stenosis performed continuous, incremental, maximal treadmill exercise tests the day before and within 3-5 days after catheter-balloon valvuloplasty. Mitral valve area determined by the echo-Doppler method increased from 0.9 +/- 0.3 cm2 to 1.9 +/- 0.7 cm2 (p < 0.02). Mean left atrial pressure was reduced from 24 +/- 8 to 13 +/- 7 mmHg (p < 0.01) and mean pulmonary artery pressure from 36 +/- 13 to 28 +/- 10 mmHg (p < 0.02) with a non-significant increase in cardiac output from 3.6 +/- 1.2 to 4.0 +/- 1.7 l/min. After catheter-balloon valvuloplasty all patients reached a higher maximal workload during exercise, and mean value of oxygen consumption and pulmonary ventilation were significantly lower in submaximal workloads. The calculated ventilatory equivalent for oxygen was significantly reduced in submaximal and in maximal workloads after catheter-balloon valvuloplasty. Peak oxygen consumption and the ventilatory anaerobic threshold were not changed after catheter-balloon valvuloplasty (pre 15.59 +/- 2.72 vs post 16.90 +/- 3.44 and pre 12.10 +/- 2.55 vs post 12.62 +/- 2.71 ml/kg/min, respectively). We concluded that after catheter-balloon valvuloplasty the cost of breathing was reduced and the oxygen consumed was more effectively utilized during exercise. Increases in peak oxygen consumption and in ventilatory anaerobic threshold would require circulatory and metabolic adaptations in response to increased physical activity and were not observed when cardiopulmonary tests were performed early after catheter-balloon valvuloplasty.


Assuntos
Cateterismo , Teste de Esforço , Estenose da Valva Mitral/terapia , Adulto , Insuficiência da Valva Aórtica/fisiopatologia , Ecocardiografia , Ecocardiografia Doppler , Feminino , Hemodinâmica/fisiologia , Humanos , Pessoa de Meia-Idade , Valva Mitral/fisiopatologia , Insuficiência da Valva Mitral/fisiopatologia , Estenose da Valva Mitral/fisiopatologia , Oxigênio/fisiologia
14.
Early Hum Dev ; 12(3): 309-21, 1985 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-4092641

RESUMO

The Golgi-Cox method was used to study the maturation of the large pyramidal cells of the Vth cortical layer in two groups of adult rats, one subjected to early postnatal malnutrition and another malnourished only during the second month of life. The main alterations were observed in the pyramidal cells of cortical layer V of rats malnourished during the first month of life. They consist of a decrease in the number and span of dendritic basilar processes. In animals malnourished during the second month of life, the number and span of basilar dendritic processes in pyramidal cells of layer V, were normal. It is postulated that early postnatal malnutrition induced immediately after birth, profoundly disturbs the process of neuronal maturation in the neocortex of the rat brain, probably with permanent effects.


Assuntos
Animais Recém-Nascidos/fisiologia , Córtex Cerebral/crescimento & desenvolvimento , Dendritos/citologia , Distúrbios Nutricionais/patologia , Fatores Etários , Animais , Peso Corporal , Córtex Cerebral/patologia , Masculino , Ratos , Ratos Endogâmicos
15.
Early Hum Dev ; 14(3-4): 245-58, 1986 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3803270

RESUMO

The Golgi-Cox method was used to study the maturation of the large pyramidal cells of the Vth cortical layer in three groups of adult rats: one subjected to undernutrition during the first month of life, another throughout the first 2 mth of life, and the last one during gestation and the suckling period. The main alterations consist of a decrease in the number and span of dendritic basilar processes of large pyramidal cells. In animals malnourished during prenatal life and the suckling period the reduction of the basal dendritic arborization was more apparent. It is postulated that the vulnerable period for the basal dendritic development occupies the period from the end of pregnancy until the first 3 wk of postnatal life in the rat (suckling period). Noxious influences acting during this phase induce sequelae that cannot be reversed by subsequent refeeding. A maintained nutritional insult during prenatal and early postnatal life induces the most severe changes in dendritic arborizations, compared to those resulting from a prolonged postnatal malnutrition.


Assuntos
Córtex Cerebral/crescimento & desenvolvimento , Dendritos/ultraestrutura , Efeitos Tardios da Exposição Pré-Natal , Deficiência de Proteína/patologia , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Animais Lactentes/crescimento & desenvolvimento , Córtex Cerebral/ultraestrutura , Feminino , Masculino , Lobo Occipital/ultraestrutura , Gravidez , Ratos , Ratos Endogâmicos
16.
Rev Inst Med Trop Sao Paulo ; 41(6): 343-50, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10671287

RESUMO

Antigenic preparations (saline, methylic, metabolic and exoantigens) of four agents of chromoblastomycosis, Fonsecaea pedrosoi, Phialophora verrucosa, Cladophialophora (Cladosporium) carrionii and Rhinocladiella aquaspersa were obtained. Partial chemical characterization of these antigenic preparations was obtained by determination of the levels of total lipids, protein, and carbohydrates, and identification of the main sterols and carbohydrates. Methylic antigens presented the highest lipid contents, whereas metabolic antigens showed the highest carbohydrate content. Total lipid, protein, and carbohydrate levels were in the range of 2.33 to 2.00 mg/ml, 0.04 to 0.02 mg/ml and 0.10 to 0.02 mg/ml, respectively, in the methylic antigens and in the range of 0. 53 to 0.18 mg/ml, 0.44 to 0.26 mg/ml, and 1.82 to 1.02 mg/ml, respectively, in saline antigens. Total lipid, protein, and carbohydrate contents were in the range of 0.55 to 0.20 mg/ml, 0.69 to 0.57 mg/ml and 10.73 to 5.93 mg/ml, respectively, in the metabolic antigens, and in the range of 0.55 to 0.15 mg/ml, 0.62 to 0.20 mg/ml and 3.55 to 0.42 mg/ml, respectively, in the exoantigens. Phospholipids were not detected in the preparations. Saline and metabolic antigens and exoantigens presented hexose and the methylic antigen revealed additional pentose units in their composition. The UV light absorption spectra of the sterols revealed squalene and an ergosterol fraction in the antigens. The characterization of these antigenic preparations may be useful for serological evaluation of patients of chromoblastomycosis.


Assuntos
Antígenos de Fungos/química , Proteínas de Bactérias/análise , Carboidratos/análise , Cromoblastomicose/imunologia , Lipídeos/análise , Fungos Mitospóricos/imunologia , Esteróis/análise
17.
Plant Biol (Stuttg) ; 16(1): 215-26, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23574349

RESUMO

Scent glands, or osmophores, are predominantly floral secretory structures that secrete volatile substances during anthesis, and therefore act in interactions with pollinators. The Leguminosae family, despite being the third largest angiosperm family, with a wide geographical distribution and diversity of habits, morphology and pollinators, has been ignored with respect to these glands. Thus, we localised and characterised the sites of fragrance production and release in flowers of legumes, in which scent plays an important role in pollination, and also tested whether there are relationships between the structure of the scent gland and the pollinator habit: diurnal or nocturnal. Flowers in pre-anthesis and anthesis of 12 legume species were collected and analysed using immersion in neutral red, olfactory tests and anatomical studies (light and scanning electron microscopy). The main production site of floral scent is the perianth, especially the petals. The scent glands are distributed in a restricted way in Caesalpinia pulcherrima, Anadenanthera peregrina, Inga edulis and Parkia pendula, constituting mesophilic osmophores, and in a diffuse way in Bauhinia rufa, Hymenaea courbaril, Erythrostemon gilliesii, Poincianella pluviosa, Pterodon pubescens, Platycyamus regnellii, Mucuna urens and Tipuana tipu. The glands are comprised of cells of the epidermis and mesophyll that secrete mainly terpenes, nitrogen compounds and phenols. Relationships between the presence of osmophores and type of anthesis (diurnal and nocturnal) and the pollinator were not found. Our data on scent glands in Leguminosae are original and detail the type of diffuse release, which has been very poorly studied.


Assuntos
Fabaceae/anatomia & histologia , Flores , Odorantes , Polinização
18.
Arq. bras. med. vet. zootec. (Online) ; 71(4): 1187-1192, jul.-ago. 2019. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1038639

RESUMO

A dislipidemia é um achado comum, porém não determinante, na síndrome metabólica equina (SME). O objetivo do presente trabalho foi caracterizar a dislipidemia em animais obesos com risco de SME. Para isso, 18 éguas foram alocadas em grupos, de acordo com escore corporal (EC) de 1 a 9: no grupo ideal, animais com EC de 4,5 a 5,5 (n= 6), no grupo sobrepeso, com EC de 6 a 7 (n= 6) e no grupo obeso, animais com EC de 7,5 a 9 (n= 6). Coletaram-se amostras de sangue em jejum de concentrado para determinação de triglicerídeos, colesterol total, glicemia e concentração de insulina. Valores preditivos de sensibilidade à insulina (RISQI) e de secreção ß-pancreática (MIRG) foram calculados. O grupo obeso apresentou níveis maiores em relação aos outros grupos de triglicerídeos (P=0,001) e acima do ideal em concentrações de colesterol (P=0,012). Não foi observada diferença nas concentrações plasmáticas de glicose (P=0,53), de insulina (P=0,10) ou de RISQI (P=0,46). Houve diferença entre os grupos nos valores de MIRG (P=0,048), tendo o grupo obeso obtido resultados maiores quando comparado com o grupo ideal. O aumento do EC foi associado ao aumento das concentrações plasmáticas de colesterol e triglicerídeos, o que caracteriza um estado de dislipidemia e de elevação da secreção das células ß-pancreáticas.(AU)


Increased indicators of fat metabolites are found in Equine Metabolic Syndrome (EMS) subjects, although these parameters are not included in the EMS definition described in the literature and in its diagnosis. The objective of this study was to characterize dyslipidemia in obese insulin resistant mares. 18 mares were allocated in three groups according to body condition score (BCS) in a 1 to 9 scale. In the Ideal group there were animals with BCS 4.5 to 5.5 (n= 6), in the Overweight group, the BCS were 6 to 7 (n= 6), and in the Obese group (n= 6), BCS 7.5 to 9. Concentrate fasting blood samples were taken to determine triglycerides, total cholesterol, glucose, and insulin concentrations in plasma. Insulin sensitivity proxy (RISQI) and ß-pancreatic secretion proxy (MIRG) were calculated from glucose and insulin data. The Obese group had higher triglyceride levels (P= 0.001), compared to other groups, and higher total cholesterol compared to the Ideal Group (P= 0.012). No differences in plasma glucose (P= 0.53), insulin (P= 0.10) concentrations and insulin sensitivity (RISQI: P= 0.463) were seen among groups. The Obese Group had a higher ß-pancreatic secretion (MIRG: P= 0.048) compared to the Ideal Group. The increased BCS was related to the plasma fat metabolites a higher ß-pancreatic secretion.(AU)


Assuntos
Animais , Feminino , Síndrome Metabólica/veterinária , Dislipidemias/veterinária , Cavalos/sangue , Obesidade/veterinária , Triglicerídeos/sangue , Glicemia/análise , Colesterol/sangue , Insulina/sangue
19.
Rev. bras. plantas med ; 17(4,supl.2): 875-880, 2015. graf
Artigo em Português | LILACS | ID: lil-771157

RESUMO

RESUMO O objetivo deste estudo foi analisar o efeito do óleo de pequi no processo cicatricial de lesões cutâneas em ratos. A pesquisa foi iniciada após a provação da CEUA- FACID sob o nº de protocolo 005/12 e obedeceu aos princípios éticos da experimentação animal de acordo com a Lei Federal nº 11.794/2008. Foram utilizados 20 ratos machos, Wistar (Rattusnorvegicus), peso corpóreo de 300-350g, divididos aleatoriamente em dois grupos iguais: GI- controle (C); GII- tratado com óleo de pequi (T). Cada grupo foi dividido em dois subgrupos, de cinco animais cada, conforme os tempos experimentais estudados de 7(A) e 14(B) dias. Após anestesia e antissepsia foi produzida cirurgicamente ferida circular de 2,5 cm de diâmetro na região dorso lombar do animal. Os animais do Grupo II foram tratados com aplicação tópica diária de 1 ml do óleo de pequi, respeitando os tempos experimentais descritos. Concomitante à mensuração da área da lesão, os ratos foram eutanasiados para realização do processamento histológico e análise do percentual de regressão das lesões. No grupo GII nos diferentes tempos experimentais de 7 e 14 dias foi observado maior percentual de regressão das lesões em relação ao GI (p < 0,05). A partir da análise histológica foi possível detectar que no GII houve menor número de células inflamatórias e maior número de fibroblastos em relação ao GI nos diferentes tempos experimentais (p < 0,001). Conclui-se que o uso do óleo de pequi apresentou influência positiva no processo de reparo de lesões cutâneas em ratos, por promover maior velocidade do reparo tecidual, fato evidenciado pelo fechamento mais rápido das feridas e observação de características inflamatórias reduzidas no grupo tratado em relação ao grupo controle, sugerindo que a inflamação pode já ter regredido no grupo tratado.


ABSTRACT The aim of this study was to analyze the effect of pequi oil in the healing process of skin lesions in rats. The research was initiated after the ordeal of CEUA- FACID with protocol No. 005/12 and following the ethical principles of animal experimentation according to the Federal Law No. 11,794 / 2008. 20 Wistar rats were used (Rattus norvegicus), with body weight ranging from 300-350g. They were randomly divided into two groups: GI control (C) and GII treated with pequi oil (T). Each group was divided into two subgroups of five animals each, according to the experimental study of 7 days (A) and 14 (B) days. After anesthesia and antisepsis, a circular wound of 2.5 cm of diameter was surgically inflicted in the lumbar dorsal region of the animal. The animals in Group II were treated with daily topical application of 1 ml of pequi oil, respecting the described experimental times. Concomitantly with the measurement of the injury area, the rats were euthanized so that a histological processing and a regression analysis of the percentage of injuries could be performed. In GII, at different experimental times of 7 and 14 days, there were a higher percentage of lesions regression compared to GI (p <0.05). From the histological examination it was possible to detect that, at GII, there were a lower number of inflammatory cells and increased number of fibroblasts compared to IM at different time of the trial (P <0.001). It is concluded that the use of pequi oil presented positive influence on the healing process of skin lesions in rats by promoting quicker tissue repair, as indicated by the faster closure of the wounds and the observation of reduced inflammatory characteristics in the group treated compared to the control group, suggesting that the inflammation could have already receded in the treated group.


Assuntos
Masculino , Ratos , Ratos/classificação , Cicatrização , Óleos Voláteis/análise , Ericales/classificação , Avulsões Cutâneas/classificação , Ferimentos e Lesões/diagnóstico , Inflamação/diagnóstico
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