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1.
Asian-Australas J Anim Sci ; 26(2): 266-74, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25049786

RESUMEN

The effect of different phytogenic feed additives on reducing odorous compounds in swine was investigated using in vitro fermentation and analyzed their microbial communities. Soybean meal (1%) added with 0.1% different phytogenic feed additives (FA) were in vitro fermented using swine fecal slurries and anaerobically incubated for 12 and 24 h. The phytogenic FAs used were red ginseng barn powder (Panax ginseng C. A. Meyer, FA1), persimmon leaf powder (Diospyros virginiana L., FA2), ginkgo leaf powder (Ginkgo biloba L., FA3), and oregano lippia seed oil extract (Lippia graveolens Kunth, OL, FA4). Total gas production, pH, ammonia-nitrogen (NH3-N), hydrogen sulfide (H2S), nitrite-nitrogen (NO2 (-)-N), nitrate-nitrogen (NO3 (-)-N), sulfate (SO4 (--)), volatile fatty acids (VFA) and other metabolites concentration were determined. Microbial communities were also analyzed using 16S rRNA DGGE. Results showed that the pH values on all treatments increased as incubation time became longer except for FA4 where it decreased. Moreover, FA4 incubated for 12 and 24 h was not detected in NH3-N and H2S. Addition of FAs decreased (p<0.05) propionate production but increased (p<0.05) the total VFA production. Ten 16S rRNA DGGE bands were identified which ranged from 96 to 100% identity which were mostly isolated from the intestine. Similarity index showed three clearly different clusters: I (FA2 and FA3), II (Con and FA1), and III (FA4). Dominant bands which were identified closest to Eubacterium limosum (ATCC 8486T), Uncultured bacterium clone PF6641 and Streptococcus lutetiensis (CIP 106849T) were present only in the FA4 treatment group and were not found in other groups. FA4 had a different bacterial diversity compared to control and other treatments and thus explains having lowest odorous compounds. Addition of FA4 to an enriched protein feed source for growing swine may effectively reduce odorous compounds which are typically associated with swine production.

2.
Asian-Australas J Anim Sci ; 25(5): 690-700, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-25049615

RESUMEN

The experiment was conducted by in vitro fermentation and bacterial community analysis to investigate the reduction of odorous compounds in response to the use of feed additives (FA) during carbohydrate overload in growing pigs. Soluble starch at 1% (control) and various FA at 0.1% Ginseng meal (FA1); Persimmon leaf (FA2); Gingko nut (FA3) and Oregano lippia (FA4) were added to fecal slurry and incubated anaerobically for 12 and 24 h. In vitro parameters and microbial diversity of the dominant bacteria following fermentation were analyzed using Denaturing Gradient Gel Electrophoresis (DGGE), band cloning and sequencing of the V3 region. Results showed that total gas production increased with the advancement of incubation (p<0.05). pH values of FAs and control groups were decreased except the FA4 group which increased somewhat from 12 to 24 h (p<0.05). Ammonia nitrogen (NH3-N) and H2S gas concentrations were comparatively lower in both stages in FA4 treatment than in the other groups (p<0.05). Hence, NH3-N concentrations in liquid phases were increased (p<0.05) from 12 to 24 h, but the trend was lowest in FA4 than in the other groups at both stages. The total VFA production was comparatively lower and butyrate levels were moderate in FA4 group than in the the other groups during both stages (p<0.05). Indirect odor-reducing compounds such as NO2, NO3 and SO4 concentrations were higher in the FA4 and FA3 than in the other groups at 24 h (p<0.05). After fermentation, ten dominant bands appeared, six of which appeared in all samples and four in only the FA4 treated group. The total number of DGGE bands and diversity was higher in the FA4-group compared to other groups. Additionally, similarity indices were lowest (71%) in the FA4, which represented a different bacterial community compared with the other groups. These findings indicate that NH3-N, H2S and VFA production was minimal, and pH was also better in the FA4 group than in the other groups. Furthermore, the conversion of odor-reducing indirect compounds or their intermediates was higher in the FA4 group in compared to the other groups. FA4 group generated less odorous products and more indirect products by in vitro fermentation at 24 h, and their microbial pattern appeared to differ from that of the other groups. These findings suggest that this particular FA could change the microbial population, which may have a beneficial effect on odor reduction. It is recommended that the oregano lippia may be supplied to growing pigs as FA along with excess carbohydrate sources to reduce the production of odorous compounds.

3.
Bone ; 41(6): 973-8, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17931994

RESUMEN

The loss of bone mineral in NASA astronauts during spaceflight has been investigated throughout the more than 40 years of space travel. Consequently, it is a medical requirement at NASA Johnson Space Center (JSC) that changes in bone mass be monitored in crew members by measuring bone mineral density (BMD), with dual-energy X-ray absorptiometry (DXA) before and after flight, of astronauts who serve on long-duration missions (4-6 months). We evaluated this repository of medical data to track whether there is recovery of bone mineral that was lost during spaceflight. Our analysis was supplemented by BMD data from cosmonauts (by convention, a space traveler formally employed by the Russia Aviation and Space Agency or by the previous Soviet Union) who had also flown on long-duration missions. Data from a total of 45 individual crew members - a small number of whom flew on more than one mission - were used in this analysis. Changes in BMD (between 56 different sets of pre- and postflight measurements) were plotted as a function of time (days after landing). Plotted BMD changes were fitted to an exponential mathematical function that estimated: (i) BMD change on landing day (day 0) and (ii) the number of days after landing when 50% of the lost bone would be recovered ("50% recovery time") in the lumbar spine, trochanter, pelvis, femoral neck and calcaneus. In sum, averaged losses of bone mineral after long-duration spaceflight ranged between 2% and 9% across all sites with our recovery model predicting a 50% restoration of bone loss for all sites to be within 9 months.


Asunto(s)
Densidad Ósea/fisiología , Enfermedades Óseas Metabólicas/metabolismo , Enfermedades Óseas Metabólicas/patología , Vuelo Espacial , Adulto , Femenino , Humanos , Masculino , Factores de Tiempo
4.
Bioresour Technol ; 96(11): 1297-303, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15734318

RESUMEN

The effects of germination temperature on the growth of barley seedlings for phytase production were studied at 15, 20 and 25 degrees C for 6-10 days. The growth rate of the barley seedlings was increased as the germination temperature was increased. The initial rate of total protein production was closely coupled to that of the barley growth, and the rate of total protein production tended to increase as the germination temperature was increased. SDS-PAGE analysis of total protein from the barley seedlings showed time-dependent appearance and disappearance of protein bands. Although no significant phytase activity was detected at zero time of germination, a significant increase in phytase activity up to 7.9-fold occurred during the first several days of germination then decreased. Phosphate production (viz. phytate degradation) in the barley seedlings occurred rapidly at the beginning of germination. However, the rate of production continued to decrease with further germination. A time lag of about 1-2 days between the rate of total protein production and that of phytase production was observed. Unlike the extent of total protein production, that of phytase production was similar irrespective of germination temperature. Partial purification of a crude enzyme extract by hydrophobic interaction chromatography resulted in two phytase fractions (PI and PII). Zymogram analysis demonstrated that PI had two bands with molecular masses of about 66 and 123 kDa while PII had one band corresponding to a molecular mass of about 96 kDa. The optimal temperature for PI was found to be 55 degrees C, while it was 50 degrees C for PII. The enzyme fraction PI had a pH optimum at 6.0, whereas the optimum pH for PII was found to be 5.0. Addition of 0.1% (v/v) Tween 80 was found to increase enzyme activity significantly (i.e., 167% for PI and 137% for PII). Phytate in cereals including barley, rice, corn and soybean degraded effectively by the treatment of the barley phytases.


Asunto(s)
6-Fitasa/biosíntesis , Reactores Biológicos , Germinación/fisiología , Hordeum , Semillas/enzimología , Temperatura , Cromatografía , Electroforesis en Gel de Poliacrilamida , Fosfatos/metabolismo , Polisorbatos , Semillas/crecimiento & desarrollo , Factores de Tiempo
5.
J Anim Sci ; 92(6): 2578-86, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24867936

RESUMEN

The objectives of this study were 1) to evaluate the effects of vaccination against foot-and-mouth disease (FMD) on growth performance, nutrient digestibility, hematological parameters, and behavior in a ruminant animal and 2) to investigate a possible strategy for reducing its adverse effect. A total of 12 Korean native goats (Capra hircus coreanae; 19.8 ± 2.9 kg) were used in a crossover design with 3 experimental periods and 3 treatments, randomized and balanced for counteracting possible carry-over effects. The treatments were 1) control, 2) co-injection with a commercially available dipyrone (CADI), and 3) supplementation with γ-amino butyric acid (GABA) at 10 g/kg in concentrate mix. Each period lasted 4 wk, and the vaccination against FMD was performed at 2 wk after the start of each period. The goats were individually housed in a metabolic cage and fed ad libitum with a diet consisting of bermuda grass and commercial concentrate mix (6:4, wt/wt). Dry matter intake, ADG, nutrients digestibility, hematological parameters, and behavioral activities of the goats were measured before and after vaccination. Although DMI was not decreased (P > 0.05), ADG was decreased by the vaccination to the goats (P < 0.01). The total number of leukocytes was increased while that of erythrocytes was decreased by the FMD vaccination (P < 0.01). The vaccination shortened standing time while extended lying time and the time spent in drinking (P < 0.05). The treatment by CADI reduced the adverse effect of vaccination on ADG and goat behavior compared with control and GABA treatment (P < 0.05). We concluded that the FMD vaccination decreased ADG of the goats without depression of diet intake, and CADI may attenuate the adverse effect of the FMD vaccination.


Asunto(s)
Fiebre Aftosa/prevención & control , Enfermedades de las Cabras/prevención & control , Vacunas Virales/inmunología , Aumento de Peso , Animales , Conducta Animal , Suplementos Dietéticos , Fármacos Gastrointestinales , Cabras , República de Corea , Vacunación , Vacunas Virales/efectos adversos
6.
Stat Med ; 17(14): 1563-80, 1998 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-9699230

RESUMEN

We present some practical extensions and applications of a strategy proposed by Thall, Simon and Estey for designing and monitoring single-arm clinical trials with multiple outcomes. We show by application how the strategy may be applied to construct designs for phase IIA activity trials and phase II equivalence trials. We also show how it may be extended to incorporate the use of mixture priors in settings where a Dirichlet distribution does not adequately quantify prior experience, randomized phase II selection trials involving two or more experimental treatments, and trials with group-sequential monitoring for applications involving multiple institutions.


Asunto(s)
Teorema de Bayes , Ensayos Clínicos Fase II como Asunto/estadística & datos numéricos , Evaluación de Procesos y Resultados en Atención de Salud/estadística & datos numéricos , Ensayos Clínicos Controlados Aleatorios como Asunto/estadística & datos numéricos , Antineoplásicos/efectos adversos , Antineoplásicos/uso terapéutico , Interpretación Estadística de Datos , Humanos , Cómputos Matemáticos , Modelos Estadísticos , Proyectos de Investigación
7.
Stat Med ; 19(8): 1011-28, 2000 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-10790677

RESUMEN

In oncology, a patient's treatment often involves multiple courses of chemotherapy. The most common medical practice in choosing treatments for successive courses is to repeat a treatment that is successful in a given course and otherwise switch to a different treatment. Patient outcome thus consists of a sequence of dependent response variables and corresponding treatments. Despite the widespread use of such adaptive 'play-the-winner-and-drop-the-loser' algorithms in medical settings involving multiple treatment courses, most statistical methods for treatment evaluation characterize early patient outcome as a single response to a single treatment, resulting in a substantial loss of information. In this paper, we provide a statistical framework for multi-course clinical trials involving some variant of the play-the-winner-and-drop-the-loser strategy. The aim is to design and conduct the trial to more closely reflect actual clinical practice, and thus increase the amount of information per patient. The proposed design is similar to a multi-stage cross-over trial, with the essential difference that here all treatments after the first course are assigned adaptively. We illustrate the method by application to a randomized phase II trial for androgen independent prostate cancer. We consider the goals of selecting one best treatment, or selecting a best ordered pair of treatments with the second given if the first fails to achieve a patient success. A simulation study is reported, and extensions to trials involving toxicity or regimen-related death are discussed.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Ensayos Clínicos Fase II como Asunto , Simulación por Computador , Modelos Estadísticos , Neoplasias de la Próstata/tratamiento farmacológico , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Cruzados , Humanos , Masculino , Antígeno Prostático Específico/sangre , Resultado del Tratamiento , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico
8.
Invest New Drugs ; 17(2): 155-67, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10638486

RESUMEN

Most statistical methods for dose-finding in phase I clinical trials determine a maximum tolerable dose based on toxicity while ignoring efficacy. Most phase II designs assume that an acceptable dose has been determined and aim to estimate treatment efficacy, possibly with early stopping rules for safety monitoring. The purpose of this paper is to describe a new statistical strategy for dose-finding in single-arm clinical trials where patient outcome is characterized in terms of both response and toxicity. The strategy, which may be considered a phase I/II hybrid, was first proposed by Thall and Russell [1] and subsequently modified by Thall [2]. The underlying mathematical model expresses the probabilities of response and toxicity as interdependent functions of dose. The method is based on fixed standards for the minimum probability of response and the maximum probability of toxicity appropriate for the particular trial. The best acceptable dose is chosen for each successive patient cohort adaptively, based on the fixed standards and the dose-outcome data from patients treated previously in the trial. The scientific goals are to select one best acceptable dose for future patients and to estimate the response and toxicity probabilities at that dose, or to stop the trial early if it becomes sufficiently unlikely that any dose is both safe and efficacious. An application of the method to a trial of donor lymphocyte infusion as salvage therapy for chemo-refractory AML/MDS patients is described. To illustrate the method's flexibility and potential breadth of application, two additional examples are provided, including a hypothetical trial in which a 5% response rate is of interest.


Asunto(s)
Evaluación de Medicamentos/normas , Modelos Estadísticos , Ensayos Clínicos como Asunto , Ensayos Clínicos Fase I como Asunto , Ensayos Clínicos Fase II como Asunto , Relación Dosis-Respuesta a Droga , Humanos , Resultado del Tratamiento
9.
Biometrics ; 57(3): 914-21, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11550945

RESUMEN

A new modality for treatment of cancer involves the ex vivo growth of cancer-specific T-cells for subsequent infusion into the patient. The therapeutic aim is selective destruction of cancer cells by the activated infused cells. An important problem in the early phase of developing such a treatment is to determine a maximal tolerated dose (MTD) for use in a subsequent phase II clinical trial. Dose may be quantified by the number of cells infused per unit body weight, and determination of an MTD may be based on the probability of infusional toxicity as a function of dose. As in a phase I trial of a new chemotherapeutic agent, this may be done by treating successive cohorts of patients at different dose levels, with each new level chosen adaptively based on the toxicity data of the patients previously treated. Such a dose-finding strategy is inadequate in T-cell infusion trials because the number of cells grown ex vivo for a given patient may be insufficient for infusing the patient at the current targeted dose. To address this problem, we propose an algorithm for trial conduct that determines a feasible MTD based on the probabilities of both infusibility and toxicity as functions of dose. The method is illustrated by application to a dendritic cell activated lymphocyte infusion trial in the treatment of acute leukemia. A simulation study indicates that the proposed methodology is both safe and reliable.


Asunto(s)
Biometría , Ensayos Clínicos como Asunto/estadística & datos numéricos , Linfocitos T/trasplante , Algoritmos , Humanos , Leucemia Mieloide Aguda/inmunología , Leucemia Mieloide Aguda/terapia , Modelos Estadísticos , Linfocitos T/inmunología , Trasplante Autólogo
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