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1.
J Dairy Sci ; 105(12): 9882-9895, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36307243

RESUMEN

The objective of the current study was to develop a predictive model for calf disease detection in the preweaning period using data from automated milk feeders (AMF). A deep convolutional neural network (CNN) architecture for the detection of respiratory disease and diarrhea in dairy calves was developed. German Holstein calves were fed milk replacer either ad libitum (up to 25 L/d; n = 32) or restrictively (6 L/d; n = 32) via AMF from 10 ± 3 d of life on. Concentrate, hay, and water were freely available. Calf health parameters were scored daily. The AMF measured milk replacer (MR) intake, number of rewarded visits, number of unrewarded visits, and drinking speed. A calf was considered sick if its fecal score was 3 or 4 and its respiratory score was 2 or 3. Only data from AMF up to 47 d of age were included in the analysis. This cut in the data was made to avoid data from the weaning period. Data were split in 80:20 ratios for training and testing data sets according to the Pareto principle. A minimum sensitivity of 80% was considered an appropriate requirement for the prediction models. Considering all calves in group housing, cross-validation of the test data set showed a sensitivity of 83% and a specificity of 79%, with a positive predictive value and a negative predictive value of 37 and 97%, respectively. The area under the curve of the receiver operating characteristic for the deep CNN model was 0.81 for all group-housed calves. The CNN model yielded sensitivity and specificity of 83 and 71%, respectively (for ad libitum-fed calves), and 82 and 87%, respectively (for restricted-fed calves), with good area under the curve-receiver operating characteristic (0.77 to 0.87), indicating that the CNN models can predict calf disease in both groups with different MR allowances. The permutation feature importance was measured by the decrease in model accuracy, and features (behaviors) were summarized in descending order of their relative importance to the CNN model. Drinking speed and MR intake were the main factors to predict calf disease in calves fed ad libitum. The number of unrewarded visits to the milk feeder and MR intake were the main factors to predict calf disease in restricted-fed calves. Despite the relatively small sample size, the results provide strong evidence that daily feeding behavior data from AMF can be used to identify calves at risk for disease. In conclusion, despite a very good testing performance of the CNN model, the relatively low daily prevalence of calf disease in the present study resulted in a high proportion of false-positive alarms.


Asunto(s)
Enfermedades de los Bovinos , Enfermedades Respiratorias , Bovinos , Animales , Leche , Alimentación Animal/análisis , Destete , Diarrea/veterinaria , Enfermedades Respiratorias/veterinaria , Redes Neurales de la Computación , Dieta/veterinaria , Peso Corporal
2.
Gynecol Oncol ; 165(2): 223-229, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35287967

RESUMEN

BACKGROUND: Patients with advanced endometrial cancer have a poor prognosis, and treatment options are limited. The investigator-initiated, multicenter, phase II DOMEC trial (NCT03951415) is the first trial to report data on efficacy and safety of combined treatment with PD-L1 and PARP inhibition for advanced endometrial cancer. PATIENTS AND METHODS: Patients with metastatic or recurrent endometrial cancer were enrolled. Patients received durvalumab 1500 mg intravenously q4w and olaparib 300 mg 2dd until disease progression, unacceptable toxicity, or patient withdrawal. Patients with at least 4 weeks of treatment were evaluable for analysis. The primary endpoint was progression-free survival at 6 months. Evidence for efficacy was defined as progression-free survival at 6 months in ≥50% of patients. Secondary endpoints included safety, objective response and overall survival. RESULTS: From July 2019, through November 2020, 55 patients were enrolled. At data cut-off (September 2021), 4 of the 50 evaluable patients were still on treatment. Seventeen patients (34%) were progression-free at 6 months. Objective response rate was 16% (95% CI, 8.3 to 28.5) with 1 complete and 7 partial responses. With a median follow-up of 17.6 months, median progression-free survival was 3.4 months (95% CI, 2.8 to 6.2) and median overall survival was 8.0 months (95% CI, 7.5 to 14.3). Grade 3 treatment-related adverse events occurred in 8 patients (16%), predominantly anemia. There were no grade 4 or 5 treatment-related adverse events. CONCLUSION: The combination of durvalumab and olaparib was well tolerated, but did not meet the prespecified 50% 6-month progression-free survival in this heterogeneous patient population with advanced endometrial cancer.


Asunto(s)
Neoplasias Endometriales , Recurrencia Local de Neoplasia , Anticuerpos Monoclonales , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias Endometriales/tratamiento farmacológico , Neoplasias Endometriales/etiología , Femenino , Humanos , Recurrencia Local de Neoplasia/patología , Ftalazinas , Piperazinas
3.
Oncogene ; 35(49): 6319-6329, 2016 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-27181206

RESUMEN

Radiation therapy is a staple approach for cancer treatment, whereas radioresistance of cancer cells remains a substantial clinical problem. In response to ionizing radiation (IR) induced DNA damage, cancer cells can sustain/activate pro-survival signaling pathways, leading to apoptotic resistance and induction of cell cycle checkpoint/DNA repair. Previous studies show that Rac1 GTPase is overexpressed/hyperactivated in breast cancer cells and is associated with poor prognosis. Studies from our laboratory reveal that Rac1 activity is necessary for G2/M checkpoint activation and cell survival in response to IR exposure of breast and pancreatic cancer cells. In this study, we investigated the effect of Rac1 on the survival of breast cancer cells treated with hyper-fractionated radiation (HFR), which is used clinically for cancer treatment. Results in this report indicate that Rac1 protein expression is increased in the breast cancer cells that survived HFR compared with parental cells. Furthermore, this increase of Rac1 is associated with enhanced activities of extracellular signal-regulated kinases 1 and 2 (ERK1/2) and nuclear factor-κB (NF-κB) signaling pathways and increased levels of anti-apoptotic protein Bcl-xL and Mcl-1, which are downstream targets of ERK1/2 and NF-κB signaling pathways. Using Rac1-specific inhibitor and dominant-negative mutant N17Rac1, here we demonstrate that Rac1 inhibition decreases the phosphorylation of ERK1/2 and inhibitory κBα (IκBα), as well as the levels of Bcl-xL and Mcl-1 protein in the HFR-selected breast cancer cells. Moreover, inhibition of Rac1 using either small molecule inhibitor or dominant-negative N17Rac1 abrogates clonogenic survival of HFR-selected breast cancer cells and decreases the level of intact poly(ADP-ribose) polymerase, which is indicative of apoptosis induction. Collectively, results in this report suggest that Rac1 signaling is essential for the survival of breast cancer cells subjected to HFR and implicate Rac1 in radioresistance of breast cancer cells. These studies also provide the basis to explore Rac1 as a therapeutic target for radioresistant breast cancer cells.


Asunto(s)
Neoplasias de la Mama/enzimología , Neoplasias de la Mama/radioterapia , Proteína de Unión al GTP rac1/metabolismo , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Línea Celular Tumoral , Supervivencia Celular/fisiología , Femenino , Humanos , Tolerancia a Radiación , Transducción de Señal , Proteína de Unión al GTP rac1/genética
4.
Eur J Clin Nutr ; 70(1): 91-6, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26105108

RESUMEN

BACKGROUND/OBJECTIVES: The daily dietary intake of selenium (Se), an essential trace element, is still low in Sweden in spite of decades of nutritional information campaigns and the effect of this on the public health is presently not well known. The objective of this study was to determine the serum Se levels in an elderly Swedish population and to analyze whether a low Se status had any influence on mortality. SUBJECTS/METHODS: Six-hundred sixty-eight (n=668) elderly participants were invited from a municipality and evaluated in an observational study. Individuals were followed for 6.8 years and Se levels were re-evaluated in 98 individuals after 48 months. Clinical examination of all individuals included functional classification, echocardiography, electrocardiogram and serum Se measurement. All mortality was registered and endpoints of mortality were assessed by Kaplan-Meier plots, and Cox proportional hazard ratios adjusted for potential confounding factors were calculated. RESULTS: The mean serum Se level of the study population (n=668) was 67.1 µg/l, corresponding to relatively low Se intake. After adjustment for male gender, smoking, ischemic heart disease, diabetes, chronic obstructive pulmonary disease and impaired heart function, persons with serum Se in the lowest quartile had 43% (95% confidence interval (CI): 1.02-2.00) and 56% (95% CI: 1.03-2.36) increased risk for all-cause and cardiovascular mortality, respectively. The result was not driven by inflammatory effects on Se concentration in serum. CONCLUSION: The mean serum Se concentration in an elderly Swedish population was 67.1 µg/l, which is below the physiological saturation level for several selenoprotein enzymes. This result may suggest the value of modest Se supplementation in order to improve the health of the Swedish population.


Asunto(s)
Enfermedades Cardiovasculares/mortalidad , Enfermedades Carenciales/complicaciones , Estado Nutricional , Selenio/sangre , Oligoelementos/sangre , Anciano , Anciano de 80 o más Años , Enfermedades Cardiovasculares/sangre , Causas de Muerte , Enfermedades Carenciales/sangre , Femenino , Humanos , Masculino , Modelos de Riesgos Proporcionales , Riesgo , Suecia/epidemiología
5.
Environ Monit Assess ; 186(11): 7617-30, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25124990

RESUMEN

Monitoring changes in land cover and the subsequent environmental responses are essential for water quality assessment, natural resource planning, management, and policies. Over the last 75 years, the Lake Issaqueena watershed has experienced a drastic shift in land use. This study was conducted to examine the changes in land cover and the implied changes in land use that have occurred and their environmental, water quality impacts. Aerial photography of the watershed (1951, 1956, 1968, 1977, 1989, 1999, 2005, 2006, and 2009) was analyzed and classified using the geographic information system (GIS) software. Seven land cover classes were defined: evergreen, deciduous, bare ground, pasture/grassland, cultivated, and residential/other development. Water quality data, including sampling depth, water temperature, dissolved oxygen content, fecal coliform levels, inorganic nitrogen concentrations, and turbidity, were obtained from the South Carolina (SC) Department of Health and Environmental Control (SCDHEC) for two stations and analyzed for trends as they relate to land cover change. From 1951 to 2009, the watershed experienced an increase of tree cover and bare ground (+17.4 % evergreen, +62.3 % deciduous, +9.8 % bare ground) and a decrease of pasture/grassland and cultivated land (-42.6 % pasture/grassland and -57.1 % cultivated). From 2005 to 2009, there was an increase of 21.5 % in residential/other development. Sampling depth ranged from 0.1 to 0.3 m. Water temperature fluctuated corresponding to changing air temperatures, and dissolved oxygen content fluctuated as a factor of water temperature. Inorganic nitrogen content was higher from December to April possibly due to application of fertilizers prior to the growing season. Turbidity and fecal coliform bacteria levels remained relatively the same from 1962 to 2005, but a slight decline in pH can be observed at both stations. Prior to 1938, the area consisted of single-crop cotton farms; after 1938, the farms were abandoned, leaving large bare areas with highly eroded soil. Starting in 1938, Clemson reforested almost 30 % of the watershed. Currently, three fourths of the watershed is forestland, with a limited coverage of small farms and residential developments. Monitoring water quality is essential in maintaining adequate freshwater supply. Water quality monitoring focuses mainly on the collection of field data, but current water quality conditions depend on the cumulative impacts of land cover change over time.


Asunto(s)
Monitoreo del Ambiente , Lagos/química , Análisis Espacio-Temporal , Agricultura/estadística & datos numéricos , Conservación de los Recursos Naturales , Fertilizantes/análisis , Fertilizantes/estadística & datos numéricos , Sistemas de Información Geográfica , Nitrógeno/análisis , South Carolina , Árboles , Calidad del Agua
6.
Br J Cancer ; 109(7): 1867-75, 2013 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-24002602

RESUMEN

BACKGROUND: Anorexia-cachexia is a common and severe cancer-related complication but the underlying mechanisms are largely unknown. Here, using a mouse model for tumour-induced anorexia-cachexia, we screened for proteins that are differentially expressed in the hypothalamus, the brain's metabolic control centre. METHODS: The hypothalamus of tumour-bearing mice with implanted methylcholanthrene-induced sarcoma (MCG 101) displaying anorexia and their sham-implanted pair-fed or free-fed littermates was examined using two-dimensional electrophoresis (2-DE)-based comparative proteomics. Differentially expressed proteins were identified by liquid chromatography-tandem mass spectrometry. RESULTS: The 2-DE data showed an increased expression of dynamin 1, hexokinase, pyruvate carboxylase, oxoglutarate dehydrogenase, and N-ethylmaleimide-sensitive factor in tumour-bearing mice, whereas heat-shock 70 kDa cognate protein, selenium-binding protein 1, and guanine nucleotide-binding protein Gα0 were downregulated. The expression of several of the identified proteins was similarly altered also in the caloric-restricted pair-fed mice, suggesting an involvement of these proteins in brain metabolic adaptation to restricted nutrient availability. However, the expression of dynamin 1, which is required for receptor internalisation, and of hexokinase, and pyruvate carboxylase were specifically changed in tumour-bearing mice with anorexia. CONCLUSION: The identified differentially expressed proteins may be new candidate molecules involved in the pathophysiology of tumour-induced anorexia-cachexia.


Asunto(s)
Anorexia/metabolismo , Caquexia/metabolismo , Regulación Neoplásica de la Expresión Génica , Hipotálamo/metabolismo , Sarcoma Experimental/metabolismo , Animales , Modelos Animales de Enfermedad , Dinamina I/biosíntesis , Subunidades alfa de la Proteína de Unión al GTP Gi-Go/biosíntesis , Proteínas HSP70 de Choque Térmico/biosíntesis , Hexoquinasa/biosíntesis , Complejo Cetoglutarato Deshidrogenasa/biosíntesis , Metilcolantreno , Ratones , Ratones Endogámicos C57BL , Proteínas Sensibles a N-Etilmaleimida/biosíntesis , Biosíntesis de Proteínas , Proteínas/metabolismo , Piruvato Carboxilasa/biosíntesis , Sarcoma Experimental/inducido químicamente , Proteínas de Unión al Selenio/biosíntesis
8.
J Comput Chem ; 30(10): 1545-614, 2009 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-19444816

RESUMEN

CHARMM (Chemistry at HARvard Molecular Mechanics) is a highly versatile and widely used molecular simulation program. It has been developed over the last three decades with a primary focus on molecules of biological interest, including proteins, peptides, lipids, nucleic acids, carbohydrates, and small molecule ligands, as they occur in solution, crystals, and membrane environments. For the study of such systems, the program provides a large suite of computational tools that include numerous conformational and path sampling methods, free energy estimators, molecular minimization, dynamics, and analysis techniques, and model-building capabilities. The CHARMM program is applicable to problems involving a much broader class of many-particle systems. Calculations with CHARMM can be performed using a number of different energy functions and models, from mixed quantum mechanical-molecular mechanical force fields, to all-atom classical potential energy functions with explicit solvent and various boundary conditions, to implicit solvent and membrane models. The program has been ported to numerous platforms in both serial and parallel architectures. This article provides an overview of the program as it exists today with an emphasis on developments since the publication of the original CHARMM article in 1983.


Asunto(s)
Simulación por Computador , Modelos Químicos , Modelos Moleculares , Teoría Cuántica , Programas Informáticos , Carbohidratos/química , Biología Computacional , Lípidos/química , Ácidos Nucleicos/química , Péptidos/química , Proteínas/química
9.
Vet Comp Orthop Traumatol ; 21(5): 440-5, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19011708

RESUMEN

This study describes the appearance of 'joint mice' in the sheath of the deep digital flexor muscle tendon (DDFT) due to osteochondritis dissecans (OCD) lesions in the talocrural joint of 12 dogs. Surgical excision of all free fragments in the DDFT sheath was performed in five dogs, and their clinical progression was documented. The excision of free fragments from the DDFT sheath, but not arthro-tomy, proved clinically beneficial despite the presence of degenerative joint disease. The anatomical communication between the talocrural joint and the DDFT sheath and its dimensions are further illustrated with the use of contrast media and dissection of cadaver limbs.


Asunto(s)
Ligamentos Colaterales/patología , Enfermedades de los Perros/patología , Enfermedades de los Perros/cirugía , Osteocondritis Disecante/veterinaria , Tendones/patología , Animales , Cadáver , Ligamentos Colaterales/cirugía , Medios de Contraste , Perros , Femenino , Cojera Animal/etiología , Cojera Animal/patología , Masculino , Osteocondritis Disecante/complicaciones , Osteocondritis Disecante/patología , Osteocondritis Disecante/cirugía , Dolor/etiología , Dolor/patología , Dolor/veterinaria , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
10.
Cell Biol Int ; 32(12): 1559-66, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18852058

RESUMEN

Efficient transformation of primary human amniocytes by E1 gene functions of human adenovirus serotype 5 (Ad5) yield in stable cell lines, which exhibit morphological features of epithelial like cells. A thorough investigation using immunocytochemistry confirmed the expression of epithelial cell markers. The analysis also revealed the expression of neuronal and glial marker proteins, such as nestin, vimentin, A2B5 and GFAP. Using RT-PCR, transcripts of the neurotrophic factors nerve growth factor (NGF), brain derived neurotrophic factor (BDNF), glial cell line derived neurotrophic factor (GDNF), and neurotrophin 3 (NT-3) could be detected. Neurotrophic factors could also be detected in the cell culture supernatants of transformed amniocytes. In line with previous experimental data on a human Ad5 E1-transformed embryonal kidney cell line (HEK-293), the results suggest a co-expression of epithelial and neuronal marker proteins in E1-transformed human amniotic fluid derived cells and thus a preferential transformation into neuronal-like cells.


Asunto(s)
Adenoviridae/genética , Amnios/citología , Células Epiteliales/citología , Neuronas/citología , Transformación Genética , Proteínas E1 de Adenovirus/genética , Amnios/metabolismo , Biomarcadores/análisis , Biomarcadores/metabolismo , Diferenciación Celular/genética , Línea Celular Transformada , Células Cultivadas , Células Epiteliales/metabolismo , Vectores Genéticos/genética , Células HeLa , Humanos , Factores de Crecimiento Nervioso/genética , Proteínas del Tejido Nervioso/análisis , Proteínas del Tejido Nervioso/metabolismo , Neuronas/metabolismo , ARN Mensajero/análisis , ARN Mensajero/metabolismo , Células Madre/citología , Células Madre/metabolismo
11.
Vet Comp Orthop Traumatol ; 21(2): 166-70, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18545722

RESUMEN

This report describes the temporary fixation of a traumatic shoulder luxation in a large-breed dog using a 3.5-mm Locking Round-Hole Reconstruction Plate (LRHRP) to provide stable internal splinting, allowing healing of the injured ligaments, joint capsule, glenohumeral ligaments, tendons, and muscles for restoration of joint stability. The use of a temporary plate with a locking system should be considered as an option in the treatment of canine shoulder joint luxations with severe tissue damage.


Asunto(s)
Placas Óseas/veterinaria , Perros , Inestabilidad de la Articulación/veterinaria , Luxación del Hombro/veterinaria , Lesiones del Hombro , Articulación del Hombro/cirugía , Animales , Fenómenos Biomecánicos , Perros/lesiones , Perros/cirugía , Inestabilidad de la Articulación/cirugía , Ligamentos Articulares/lesiones , Ligamentos Articulares/cirugía , Masculino , Luxación del Hombro/cirugía , Traumatismos de los Tendones/cirugía , Traumatismos de los Tendones/veterinaria , Resultado del Tratamiento , Soporte de Peso/fisiología
12.
Clin Microbiol Infect ; 12(4): 331-7, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16524409

RESUMEN

Cerebrospinal fluid (CSF) shunts carry a high risk of complications. Infections represent a major cause of shunt failure. Diagnosis and therapy of such infections are complicated by the formation of bacterial biofilms attached to shunt surfaces. This study correlated the pathophysiology and clinical course of biofilm infections with microscopical findings on the respective shunts. Surface irregularities, an important risk-factor for shunt colonisation with bacteria, were found to increase over time because of silicone degradation. Scanning electron-microscopy (SEM) documented residual biological material (dead biofilm), which can further promote extant bacterial adhesion, on newly manufactured shunts. Clinical course and SEM both documented bacterial dissemination against CSF flow and the monodirectional valve. In all cases, biofilms grew on both the inner and outer surfaces of the shunts. Microscopy and conventional culture detected all bacterial shunt infections. Analyses of 16S rDNA sequences using conserved primers identified bacteria in only one of three cases, probably because of previous formalin fixation of the samples.


Asunto(s)
Infecciones Bacterianas/diagnóstico , Biopelículas , Derivaciones del Líquido Cefalorraquídeo , Adolescente , Adulto , Bacterias/genética , Bacterias/aislamiento & purificación , Infecciones Bacterianas/microbiología , ADN Bacteriano/análisis , ADN Ribosómico/análisis , Femenino , Humanos , Masculino , Microscopía Electrónica de Rastreo , ARN Ribosómico 16S/genética
13.
Ann N Y Acad Sci ; 994: 84-9, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12851301

RESUMEN

Melanocortin receptor-based drug discovery is particularly active in the field of neuroendocrine systems and is mostly related to food intake and novel obesity therapies. The immunomodulatory and anti-inflammatory effects of nonpeptidic, low molecular weight compounds activating the melanocortin-1 receptor (MC1R) provide a new principle for treating various types of inflammation, such as dermal, joint, and gastrointestinal, probably by virtue of the effects acting through modulation of proinflammatory and anti-inflammatory cytokines. Several reports demonstrate that alpha-MSH, for example, has anti-inflammatory effects in different models. The aim of our study was to design, synthesize, and characterize compounds that bind to and activate the MC1R in vitro. The binding affinities are submicromolar to this receptor, and activation of the receptor (cAMP assay) varies from full agonists to partial agonists as well as antagonists. In vivo, the compounds exert prominent anti-inflammatory effects, with efficacy in the same range as that of dexamethasone, for example. The potential advantages of MC1R-based anti-inflammatory effects versus glucocorticosteroids, for example, are that the latter, albeit exerting prominent anti-inflammatory effects, also have many side effects that most likely will not characterize an MC1R-based anti-inflammatory drug.


Asunto(s)
Antiinflamatorios/metabolismo , Diseño de Fármacos , Receptores de Corticotropina/metabolismo , Animales , Antiinflamatorios/uso terapéutico , Línea Celular , Dexametasona/farmacología , Dinitrofluorobenceno/toxicidad , Edema/inducido químicamente , Edema/tratamiento farmacológico , Femenino , Glucocorticoides/farmacología , Humanos , Ligandos , Ratones , Ratones Endogámicos BALB C , Peso Molecular , Análisis Multivariante , Prednisolona/farmacología , Receptores de Corticotropina/agonistas , Receptores de Melanocortina , alfa-MSH/química , alfa-MSH/metabolismo
14.
Acta Neurochir Suppl ; 86: 399-405, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14753476

RESUMEN

The possibility that five new low molecular weight compounds with varying affinity and selectivity to the melanocortin receptors will exert neuroprotective effects in the spinal cord injury (SCI) induced edema formation and cell damage was examined in a rat model. A focal trauma of the rat spinal cord made by an incision into the right dorsal horn (T10-11) resulted in profound edema formation, leakage of Evans blue albumin and cell injury of the T9 segment at 5 h. Topical application of the Melacure compound ME10501 in high doses (10 microg in 10 microl) given 5 min after SCI resulted in most significant neuroprotection of the T9 segment of the cord compared to other compounds. Thus, marked reduction in water content, leakage of Evans blue albumin, and cell injury were observed in ME10501 treated traumatised rats. These observations suggest that the non-peptide compound ME10501 with affinity to the melanocortin receptor MC4 is capable to induce neuroprotection in the spinal cord following trauma not reported earlier.


Asunto(s)
Fármacos Neuroprotectores/farmacología , Receptores de Melanocortina/metabolismo , Traumatismos de la Médula Espinal/patología , Animales , Unión Competitiva , Agua Corporal/metabolismo , Permeabilidad Capilar/efectos de los fármacos , Edema/etiología , Masculino , Peso Molecular , Ratas , Ratas Sprague-Dawley , Médula Espinal/irrigación sanguínea , Médula Espinal/efectos de los fármacos , Médula Espinal/patología , Médula Espinal/fisiopatología , Enfermedades de la Médula Espinal/etiología , Traumatismos de la Médula Espinal/complicaciones
15.
J Wildl Dis ; 38(3): 621-4, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12238384

RESUMEN

A juvenile woodchuck (Marmota monax) with vestibular signs was found in Woodbridge, Ontario (Canada) and later euthanized. At necropsy there was marked distortion of the right side of the skull, where a large, fluctuant, subcutaneous mass extended under the zygomatic arch and caudally from the right eye towards the right ear. The mass was multiloculated and contained a large number of tapeworm cysticerci, each about 1 to 2 mm in diameter. The third and lateral ventricles of the brain were dilated and contained large numbers of similar cysticerci. Based on the exogenous budding of cysts and the morphology of the scolex in each cyst, they were identified as cysticerci of Taenia crassiceps. This is the first report of cerebral cysticercosis in a woodchuck.


Asunto(s)
Marmota/parasitología , Neurocisticercosis/veterinaria , Animales , Encéfalo/parasitología , Encéfalo/patología , Cysticercus/anatomía & histología , Cysticercus/clasificación , Cysticercus/aislamiento & purificación , Resultado Fatal , Femenino , Neurocisticercosis/diagnóstico por imagen , Neurocisticercosis/patología , Radiografía , Cráneo/diagnóstico por imagen
16.
Peptides ; 23(1): 143-9, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11814629

RESUMEN

The effects of intraperitoneal (i.p.) administration of kainic acid (KA) and alpha-melanocyte-stimulating hormone (alpha-MSH) alone or in combination, on core temperature of freely moving rats were examined. KA or saline was administered once (10 mg/kg) and alpha-MSH or saline was given repeatedly i.e. 10 min before and 10, 30 and 60 min after the administration of saline or KA. Two doses of alpha-MSH were used: 0.5 and 2.5 mg/kg. KA alone produced a biphasic effect on core temperature, i.e. an initial short-lasting hypothermia followed by hyperthermia that lasted about 6 h. The higher dose of alpha-MSH had a potentiating effect on KA-induced hypothermia, while the lower dose of alpha-MSH increased the hyperthermia produced by KA. alpha-MSH administered alone produced a late (3 h), dose-dependent increase in core temperature. It is conceivable that repeated administration of alpha-MSH in the doses used in our study may cause a cumulative effect in raising body temperature for a limited period of time. The previously described interactions between KA and alpha-MSH, respectively, with dopaminergic and serotoninergic systems may account for the effects on core temperature in rats observed in our study.


Asunto(s)
Temperatura Corporal/efectos de los fármacos , Ácido Kaínico/metabolismo , alfa-MSH/farmacología , Animales , Relación Dosis-Respuesta a Droga , Hipotermia , Masculino , Ratas , Ratas Sprague-Dawley , Factores de Tiempo
19.
Biochim Biophys Acta ; 1544(1-2): 350-7, 2001 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-11341944

RESUMEN

A novel method has been developed for the analysis of ligand-receptor interactions. The method utilizes binding data generated from the analysis of chimeric proteins with chimeric peptides. To each chimeric part of the peptide and receptor are assigned descriptors, thus creating a matrix of X descriptors. These descriptors are then correlated with the experimentally determined interaction binding affinities for each chimeric receptor/peptide pair by use of partial least-squares projection to latent structures (PLS). The method was applied to analyze the interactions of chimeric MSH-peptides with wild-type MC1 and MC3 receptors, and MC1/MC3 receptor chimeras (in total 40 peptide-receptor combinations). Two types of PLS models could be created, one that revealed the relationships between receptor and peptide structure and peptide binding pK(i) values (i.e., affinity) (R2 and Q2 being 0.71 and 0.62, respectively), and another that revealed the relationships between peptide and receptor structure and peptide-receptor selectivity (R2 and Q2 being 0.64 and 0.57, respectively). After addition of cross-terms these models improved significantly; the R2 and Q2 being 0.93 and 0.75 for affinity, and 0.92 and 0.72 for selectivity, respectively. The analysis shows that the high affinity of the MSH-peptides is primarily achieved by interactions of the peptides' C-terminal amino acids with TM2 and TM3 of the receptor, and, to a lesser extent, by the interaction of the N-terminus with TM1, TM2 and TM3 of the receptor. However, in contrast, the MC1 receptor selectivity is primarily determined by an interaction of the peptides' N-termini with TM2/3 of the receptor. Moreover, the cross-terms of the PLS model revealed the existence of a strong interaction between TM6/7 and TM2/3 of the receptors.


Asunto(s)
Hormonas Estimuladoras de los Melanocitos/metabolismo , Péptidos/metabolismo , Isoformas de Proteínas/metabolismo , Receptores de Corticotropina/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , Secuencia de Aminoácidos , Ligandos , Hormonas Estimuladoras de los Melanocitos/química , Datos de Secuencia Molecular , Unión Proteica , Receptores de Melanocortina , Homología de Secuencia de Aminoácido
20.
Diabetes ; 50(5): 980-4, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11334441

RESUMEN

The early three (E3) region of the adenovirus (Ad) encodes a number of immunomodulatory proteins that interfere with class I major histocompatibility-mediated antigen presentation and confer resistance to cytokine-induced apoptosis in cells infected by the virus. Transgenic expression of Ad E3 genes under the rat insulin II promoter (RIP-E3) in beta-cells in nonobese diabetic (NOD) mice decreases the incidence and delays the onset of autoimmune diabetes. The immune effector cells of RIP-E3/NOD mice maintain the ability to infiltrate the islets and transfer diabetes into NOD-scid recipients, although at a significantly reduced rate compared with wild-type littermates. The islets of RIP-E3/ NOD mice can be destroyed by adoptive transfer of splenocytes from wild-type NOD mice; however, the time to onset of hyperglycemia is delayed significantly, and 40% of these recipients were not diabetic at the end of the experiment. These findings suggest that expression of E3 genes in beta-cells affects both the activation of immune effector cells and the intrinsic resistance of beta-cells to autoimmune destruction.


Asunto(s)
Adenoviridae/genética , Proteínas E3 de Adenovirus/genética , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/inmunología , Proteínas E3 de Adenovirus/inmunología , Traslado Adoptivo , Envejecimiento , Animales , Cruzamientos Genéticos , Diabetes Mellitus Tipo 1/epidemiología , Femenino , Incidencia , Insulina/genética , Islotes Pancreáticos/inmunología , Islotes Pancreáticos/patología , Transfusión de Linfocitos , Ratones , Ratones Endogámicos NOD , Ratones Endogámicos , Ratones SCID , Ratones Transgénicos , Regiones Promotoras Genéticas , Ratas , Bazo/inmunología
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