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1.
J Dairy Sci ; 101(5): 4235-4244, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29477524

RESUMEN

This study aimed to investigate the effect of dietary supplementation with leucine and phenylalanine on pancreas development, enzyme activity, and related gene expression in male Holstein calves. Twenty male Holstein calves [1 d of age, 38 ± 3 kg of body weight (BW)] were randomly assigned to 1 of the following 4 treatment groups with 5 calves in each group: control, leucine supplementation (1.435 g/L of milk), phenylalanine supplementation (0.725 g/L of milk), and leucine and phenylalanine (1.435 + 0.725 g/L of milk). The diets were made isonitrogenous with the inclusion of alanine in each respective treatment. The feeding trial lasted for 8 wk, including 1 wk for adaption and 7 wk for the feeding experiment. Leucine tended to increase the concentration of total pancreatic protein (mg/kg of BW). Phenylalanine increased the concentrations of plasma insulin, cholecystokinin, and pancreatic DNA (mg/g) and the expression of trypsin gene but decreased the pancreatic protein:DNA ratio and tended to decrease the pancreas weight (g/kg of BW). No differences were observed in total pancreatic DNA (mg/pancreas and mg/kg of BW), pancreatic protein (mg/pancreas), or activities of α-amylase, trypsin, and lipase. The relative expression levels of the genes encoding α-amylase and lipase did not differ among the 4 groups. The supplementation of both leucine and phenylalanine showed an interaction on the pancreas weight (g and g/kg of BW) and a tendency of an interaction on the pancreatic protein concentration (mg/g of pancreas and mg/kg of BW) and the plasma glucose concentration. Leucine tended to increase the size of the pancreatic cells, whereas phenylalanine tended to increase the number of pancreatic cells. However, neither AA affected the activities of the pancreatic enzymes of the calves. These results indicate that leucine and phenylalanine supplementation in milk-fed Holstein calves differentially affect pancreatic growth and development.


Asunto(s)
Bovinos/genética , Bovinos/metabolismo , Leucina/metabolismo , Leche/metabolismo , Páncreas/crecimiento & desarrollo , Fenilalanina/metabolismo , Alimentación Animal/análisis , Animales , Peso Corporal , Bovinos/crecimiento & desarrollo , Suplementos Dietéticos/análisis , Femenino , Expresión Génica , Masculino , Páncreas/enzimología , alfa-Amilasas
2.
AAPS J ; 20(1): 25, 2017 12 28.
Artículo en Inglés | MEDLINE | ID: mdl-29285735

RESUMEN

The American Association of Pharmaceutical Scientists (AAPS) biosimilar focus group on nonclinical and clinical assays has developed this manuscript to guide the industry on best practices and testing strategies when developing neutralizing antibody (NAb) assays for biosimilar programs. The immunogenicity assessment to biosimilar and originator drug products is one of the key aspects of clinical programs for biosimilars to demonstrate biosimilarity. Establishing that there are no clinically meaningful differences in immune response between a proposed product and the originator product is a key element in the demonstration of biosimilarity. It is critical to collect, evaluate, and compare the safety and immunogenicity data from the clinical pharmacology, safety, and/or efficacy studies especially when the originator drug product is known to have potential for immune-mediated toxicity. This manuscript aims to provide a comprehensive review and recommendations on assay formats, critical reagents, approaches to method development, and validation of the neutralizing antibody assays in extrapolation within the scope of biosimilar drug development programs. Even if there are multiple options on the development and validation of NAb assays for biosimilar programs, the type of drug and its MoA will help determine the assay format and technical platform for NAb assessment (e.g., cell-based or non-cell-based assay). We recommend to always perform a one-assay approach as it is better to confirm the biosimilarity using one-assay for NAb. If a one-assay approach is not feasible, then a two-assay format may be used. This manuscript will provide all the details necessary to develop NAb assays for biosimilars.


Asunto(s)
Inmunidad Adaptativa/efectos de los fármacos , Anticuerpos Neutralizantes/análisis , Bioensayo/métodos , Biosimilares Farmacéuticos/farmacología , Estudios de Validación como Asunto , Animales , Bioensayo/normas , Línea Celular , Evaluación Preclínica de Medicamentos/métodos , Evaluación Preclínica de Medicamentos/normas , Humanos , Modelos Animales
3.
CPT Pharmacometrics Syst Pharmacol ; 6(3): 177-187, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28294568

RESUMEN

Massive cancer genomics data have facilitated the rapid revolution of a novel oncology drug discovery paradigm through targeting clinically relevant driver genes or mutations for the development of precision oncology. Natural products with polypharmacological profiles have been demonstrated as promising agents for the development of novel cancer therapies. In this study, we developed an integrated systems pharmacology framework that facilitated identifying potential natural products that target mutated genes across 15 cancer types or subtypes in the realm of precision medicine. High performance was achieved for our systems pharmacology framework. In case studies, we computationally identified novel anticancer indications for several US Food and Drug Administration-approved or clinically investigational natural products (e.g., resveratrol, quercetin, genistein, and fisetin) through targeting significantly mutated genes in multiple cancer types. In summary, this study provides a powerful tool for the development of molecularly targeted cancer therapies through targeting the clinically actionable alterations by exploiting the systems pharmacology of natural products.


Asunto(s)
Productos Biológicos/administración & dosificación , Descubrimiento de Drogas/métodos , Terapia Molecular Dirigida/métodos , Mutación/genética , Neoplasias/genética , Medicina de Precisión/métodos , Ensayos Clínicos como Asunto/estadística & datos numéricos , Bases de Datos Factuales/tendencias , Descubrimiento de Drogas/tendencias , Humanos , Medicina Tradicional China/métodos , Medicina Tradicional China/tendencias , Terapia Molecular Dirigida/tendencias , Neoplasias/tratamiento farmacológico , Medicina de Precisión/tendencias
4.
J Endocrinol Invest ; 40(7): 713-719, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28213641

RESUMEN

OBJECTIVE: To explore the underlying mechanism and treatment of myocardial injury caused by hypothyroidism, we evaluated oxidative stress in serum and myocardial tissue of hypothyroid rats. The effect of levothyroxine (LT4) replacement therapy and vitamin E (VitE) supplementation on oxidative stress-induced injury and apoptosis of myocardial tissue is examined. METHODS: Male Sprague-Dawley rats were divided into five groups: normal control group, propylthiouracil group (PTU group), LT4 treatment group (PTU + LT4 group), vitamin E treatment group (PTU + VitE group), and combined treatment group (PTU + LT4 + VitE group). Superoxide dismutase (SOD) activity and malondialdehyde (MDA) expression in serum and myocardium were determined. Myocardial apoptosis index (AI) in each group was determined by TUNEL assay. RESULTS: SOD levels in serum were significantly increased in PTU + VitE and PTU + LT4 + Vit E groups, as compared to that in PTU and PTU + LT4 groups (P < 0.05). MDA levels in serum and myocardial tissue were significantly lower in PTU + LT4, PTU + VitE, and PTU + LT4 + VitE groups, as compared to that in the PTU group (P < 0.05). Myocardial apoptosis was significantly increased in PTU and PTU + VitE groups as compared to that in the normal control group (P < 0.05), while it was significantly lower in PTU + LT4 and PTU + LT4 + VitE groups, as compared to that in the PTU group (P < 0.05). CONCLUSION: In this study, levothyroxine replacement therapy and vitamin E supplementation appeared to ameliorate myocardial apoptosis in hypothyroid rats, the mechanism of which appears to be related to improved thyroid function and reduced oxidative stress.


Asunto(s)
Apoptosis/efectos de los fármacos , Cardiomiopatías/tratamiento farmacológico , Suplementos Dietéticos , Hipotiroidismo/fisiopatología , Estrés Oxidativo , Tiroxina/administración & dosificación , Vitamina E/administración & dosificación , Animales , Antioxidantes/administración & dosificación , Cardiomiopatías/etiología , Cardiomiopatías/patología , Hipotiroidismo/complicaciones , Masculino , Ratas , Ratas Sprague-Dawley
5.
J Appl Microbiol ; 114(6): 1582-91, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23480628

RESUMEN

AIMS: To determine the effects of Lactobacillus fermentum I5007 on the redox state of piglets oxidatively stressed with diquat. METHODS AND RESULTS: Twenty-four, 28-day-old barrows were used in a 2 × 2 factorial design experiment with the main effects being Lact. fermentum supplementation and diquat challenge. Half of the pigs (n = 12) were orally administered with 20 ml of a solution containing 10(8 ) CFU ml(-1) of Lact. fermentum each morning of the 21-day trial, while the remainder received saline. On day 8, these two groups were further subdivided so that half of the pigs in each group (n = 6) were intraperitoneally injected with 10 mg kg(-1) BW diquat, while the remainder received saline. The diquat-injected pigs had significantly poorer performance and increased levels of plasma cortisol, adrenaline, carbonyl and malondialdehyde. Lactobacillus fermentum supplementation significantly increased superoxide dismutase and glutathione and increased the ability to inhibit superoxide anion production in liver and muscle. CONCLUSIONS: Lactobacillus fermentum improved the anti-oxidative defence system and alleviated damage caused by diquat. SIGNIFICANCE AND IMPACT OF THE STUDY: Lactobacillus fermentum has the potential to alleviate oxidative stress and improve weaning pig performance.


Asunto(s)
Diquat/toxicidad , Herbicidas/toxicidad , Limosilactobacillus fermentum , Estrés Oxidativo , Animales , Suplementos Dietéticos , Hígado/metabolismo , Malondialdehído/metabolismo , Músculos/metabolismo , Oxidación-Reducción , Superóxido Dismutasa/metabolismo , Porcinos , Destete
6.
Comput Biol Med ; 35(8): 717-24, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16124992

RESUMEN

Text-based search is widely used for biomedical data mining and knowledge discovery. Character errors in literatures affect the accuracy of data mining. Methods for solving this problem are being explored. This work tests the usefulness of the Smith-Waterman algorithm with affine gap penalty as a method for biomedical literature retrieval. Names of medicinal herbs collected from herbal medicine literatures are matched with those from medicinal chemistry literatures by using this algorithm at different string identity levels (80-100%). The optimum performance is at string identity of 88%, at which the recall and precision are 96.9% and 97.3%, respectively. Our study suggests that the Smith-Waterman algorithm is useful for improving the success rate of biomedical text retrieval.


Asunto(s)
Algoritmos , Almacenamiento y Recuperación de la Información/métodos , Procesamiento de Lenguaje Natural , Bases de Datos Bibliográficas , Reconocimiento de Normas Patrones Automatizadas , Plantas Medicinales
7.
Am J Chin Med ; 33(2): 281-97, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15974487

RESUMEN

Traditional Chinese medicine (TCM) has been widely practiced and is considered as an alternative to conventional medicine. TCM herbal prescriptions contain a mixture of herbs that collectively exert therapeutic actions and modulating effects. Traditionally defined herbal properties, related to the pharmacodynamic, pharmacokinetic and toxicological, as well as physicochemical properties of their principal ingredients, have been used as the basis for formulating TCM multi-herb prescriptions. These properties are used in this work to develop a computer program for predicting whether a multi-herb recipe is a valid TCM prescription. This program is based on a statistical learning method, support vector machine (SVM), and it is trained by using 575 well-known TCM prescriptions and 1961 non-TCM recipes generated by random combination of TCM herbs. Testing results by using 72 well-known TCM prescriptions and 5039 non-TCM recipes showed that 73.6% of the TCM prescriptions and 99.9% of non-TCM recipes are correctly classified by this system. A further test by using 48 TCM prescriptions published in recent years found that 68.7% of these are correctly classified. These accuracies are comparable to those of SVM classification of other biological systems. Our study indicates the potential of SVM for facilitating the analysis of TCM prescriptions.


Asunto(s)
Diseño de Fármacos , Medicamentos Herbarios Chinos/efectos adversos , Medicamentos Herbarios Chinos/farmacología , Programas Informáticos , Química Farmacéutica , Prescripciones de Medicamentos , Humanos , Medicina Tradicional China
8.
Toxicol Sci ; 79(1): 170-7, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-14976348

RESUMEN

In an effort to facilitate drug discovery, computational methods for facilitating the prediction of various adverse drug reactions (ADRs) have been developed. So far, attention has not been sufficiently paid to the development of methods for the prediction of serious ADRs that occur less frequently. Some of these ADRs, such as torsade de pointes (TdP), are important issues in the approval of drugs for certain diseases. Thus there is a need to develop tools for facilitating the prediction of these ADRs. This work explores the use of a statistical learning method, support vector machine (SVM), for TdP prediction. TdP involves multiple mechanisms and SVM is a method suitable for such a problem. Our SVM classification system used a set of linear solvation energy relationship (LSER) descriptors and was optimized by leave-one-out cross validation procedure. Its prediction accuracy was evaluated by using an independent set of agents and by comparison with results obtained from other commonly used classification methods using the same dataset and optimization procedure. The accuracies for the SVM prediction of TdP-causing agents and non-TdP-causing agents are 97.4 and 84.6% respectively; one is substantially improved against and the other is comparable to the results obtained by other classification methods useful for multiple-mechanism prediction problems. This indicates the potential of SVM in facilitating the prediction of TdP-causing risk of small molecules and perhaps other ADRs that involve multiple mechanisms.


Asunto(s)
Biología Computacional/métodos , Evaluación Preclínica de Medicamentos/métodos , Torsades de Pointes/inducido químicamente , Torsades de Pointes/diagnóstico , Algoritmos , Aminoglicósidos/química , Aminoglicósidos/farmacología , Antibacterianos/química , Antibacterianos/farmacología , Biología Computacional/clasificación , Biología Computacional/estadística & datos numéricos , Interpretación Estadística de Datos , Desamino Arginina Vasopresina/efectos adversos , Desamino Arginina Vasopresina/química , Modelos Teóricos , Octreótido/efectos adversos , Octreótido/química , Torsades de Pointes/fisiopatología
9.
Artículo en Chino | MEDLINE | ID: mdl-21171429

RESUMEN

AIM AND METHODS: To observe the effect of temperature on multi-order open of delayed rectifier K+ channels in hypothalamic-neurons by cell-attached mode of patch-clamp technique. RESULTS: With temperature raising, the probability of open-channel recording increased, multichannel open occurred. The density of open - channel on membrane of 32 degrees C, 37 degrees C and 39 degrees C was 0.71, 1.22 and 1.82 channels/microm2 respectively (P < 0.05). CONCLUSION: More Ik of hypothalamus opened with temperature raising, this benefited to the body temperature regulation of neurons in hypothalamus.


Asunto(s)
Canales de Potasio de Tipo Rectificador Tardío/fisiología , Hipotálamo/citología , Neuronas/fisiología , Temperatura , Animales , Células Cultivadas , Potenciales de la Membrana , Técnicas de Placa-Clamp , Ratas , Ratas Sprague-Dawley
10.
Artículo en Chino | MEDLINE | ID: mdl-21207682

RESUMEN

AIM: To investigate the characteristics of single L-type Ca2+ channels in hypothalamic neurons. METHODS: The cell-attached patch-clamp technique and acute cell isolation technique were used. RESULTS: (1) L-type Ca2+ channels opened throughout an 768 ms long voltage pulse. (2) The averaged open-time constant was 0.28 ms(tau0), two closed-time constants were 2.91 (tau(c1)) and 53.22 ms(tau(c2)). (3) The conductance was (29.5 +/- 3.1) pS and (4) Bay K 8644 increased the open probability by prolonging the mean open time to 1.61 ms. CONCLUSION: L-type Ca2+ channel existed in hypothalamic neurons, with the similar properties to Ca2+ currents as previously reported, but showed its own peculiarity.


Asunto(s)
Canales de Calcio Tipo L/fisiología , Hipotálamo/citología , Neuronas/fisiología , Animales , Animales Recién Nacidos , Hipotálamo/fisiología , Técnicas de Placa-Clamp , Ratas , Ratas Sprague-Dawley
11.
Zhongguo Yao Li Xue Bao ; 18(3): 286-8, 1997 May.
Artículo en Chino | MEDLINE | ID: mdl-10072954

RESUMEN

AIM: To compare the total coumarins from dried fruits of Cnidium monnieri (TCCM) and nilestriol (Nil) against osteoporosis. METHODS: SD rats (40, female, 3-month-old) were randomly divided into basal control, age control, ovariectomized (Ova), Ova + TCCM 67 mg.kg-1, Ova + TCCM 200 mg.kg-1, 6 times a week, and Ova + Nil 1 mg.kg-1, i.g. once a week. After 12 wk, sections (20 microns) of proximal tibiae were examined histologically. RESULTS: Ova reduced markedly the trabecular bone mass due to bone resorption excessed bone formation (% Tb. Ar -59%). Treatment with TCCM 67 mg.kg-1 partly suppressed bone turnover, but did not inhibit bone loss in Ova rats (% Tb.Ar -43%). Treatment with TCCM 200 mg.kg-1 and Nil 1 mg.kg-1 increased the trabecular area (% Tb. Ar +100% and +274%). CONCLUSION: Nil was more potent than TCCM in protecting against osteoporosis in Ova rats via supression of bone turnover.


Asunto(s)
Apiaceae , Cumarinas/uso terapéutico , Osteoporosis Posmenopáusica/prevención & control , Quinestrol/análogos & derivados , Animales , Apiaceae/química , Resorción Ósea/prevención & control , Cumarinas/aislamiento & purificación , Femenino , Humanos , Ovariectomía , Quinestrol/uso terapéutico , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Tibia
12.
J Biol Chem ; 272(19): 12831-9, 1997 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-9139744

RESUMEN

Previously, we generated monoclonal antibodies against chicken corneal cells (Zak, N. B., and Linsenmayer, T. F. (1983) Dev. Biol. 99, 373). We have now observed that one group of these antibodies reacts with a developmentally regulated component of corneal epithelial cell nuclei. This component is the heavy chain of ferritin, as determined by analyses of immunoisolated cDNA clones and immunoblotting of the protein. Immunoblotting also suggests that the nuclear ferritin may be in a supramolecular form that is similar to the iron-binding ferritin complex found in the cytoplasm of many cells. In vitro cultures and transfection studies show that the nuclear localization depends predominantly on cell type but can be altered by the in vitro environment. The appearance of nuclear ferritin is at least partially under translational regulation, as is known to be true for the cytoplasmic form of the molecule. The tissue and developmental distributions of the mRNA for the molecule are much more extensive than the protein itself, and the removal of iron from cultures of corneal epithelial cells with the iron chelator deferoxamine prevents the appearance of nuclear ferritin. At present the functional role(s) of nuclear ferritin remain unknown, but previous studies on cytoplasmic ferritin raise the possibility that it prevents damage due to free radical generation ("oxidative stress") by sequestering iron. Although it remains to be tested whether nuclear ferritin prevents oxidative damage, we find this an attractive possibility. Since the corneal epithelium is transparent and is constantly exposed to free radical-generating UV light, it is possible that the cells of this tissue have evolved a specialized mechanism to prevent oxidative damage to their nuclear components.


Asunto(s)
Córnea/metabolismo , Ferritinas/metabolismo , Proteínas Nucleares/metabolismo , Animales , Anticuerpos Monoclonales , Pollos , Córnea/citología , ADN Complementario/química , Epitelio/metabolismo , Ferritinas/genética , Microscopía Fluorescente , Conformación Proteica , Especies Reactivas de Oxígeno/metabolismo , Rayos Ultravioleta
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