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1.
J Dairy Sci ; 100(7): 5922-5927, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28478009

RESUMEN

We developed a reproductive tract size and position score (SPS) system as a reproductive management tool to identify lactating dairy cows with decreased fertility. This system, relying solely on transrectal palpation, considers the size (cervical and uterine) and position of the reproductive tract relative to the pelvis. Cows undergoing pre-breeding exams were identified as having reproductive tracts that were small (SPS1), medium (SPS2), or large (SPS3). Cows designated SPS1 had small and compact uterine horns that rested within the pelvic cavity; SPS2 cows had reproductive tracts that were intermediate in cervical and uterine horn diameter, with longer uterine horns resting partially outside the pelvic cavity; and SPS3 cows had reproductive tracts that were larger and rested mostly outside the pelvic cavity. Cows that were SPS1 had a higher rate of pregnancy per artificial insemination (43.3 ± 3.7%) than cows that were SPS2 (36.9 ± 3.6%) or SPS3 (27.7 ± 4.3%). The percentage of cows with an SPS2 score differed in pregnancies per artificial insemination compared with SPS3 cows. The average days in milk was similar for SPS1, SPS2, and SPS3 cows (104.3 ± 3.5, 98.4 ± 3.4, and 94.7 ± 7.7, respectively). Ultrasound measurements of the uterine horn and cervical diameter, and length measurements of the uterine horns, cervix, and vagina confirmed differences among the SPS groups derived by transrectal palpation. The ease with which transrectal palpation can be used to determine the size and position of the reproductive tract attests to the relevance and usefulness of this scoring system to identify less fertile lactating dairy cows. The ability to do so with ease provides an opportunity to make economically relevant management decisions and maximize reproductive efficiency in a given herd.


Asunto(s)
Bovinos/fisiología , Fertilidad/fisiología , Examen Físico/veterinaria , Reproducción/fisiología , Fenómenos Fisiológicos Reproductivos , Animales , Femenino , Inseminación Artificial , Lactancia/fisiología , Leche , Embarazo
2.
BMJ Mil Health ; 169(1): 84-88, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35042757

RESUMEN

Servicewomen are at increased risk of musculoskeletal injuries compared with their male counterparts, but women are under-represented in sports medicine research. The aim of this review was to assess the representation of women in military musculoskeletal injury studies. PubMed was searched for human original research studies using the terms Military OR Army OR Navy OR 'Air Force' AND 'musculoskeletal injury' Each study was categorised as epidemiology (basic training), epidemiology (trained personnel), risk factors, interventions and other. The number of male and female participants was retrieved from each study. A total of 262 studies were included: 98 (37%) studies only included men, 17 (6%) studies only included women and 147 (56%) studies included both men and women. A total of 8 051 778 participants were included in these studies (men: 6 711 082, 83%; women: 1 340 696, 17%). The study theme with the greatest proportion of women was musculoskeletal injury epidemiology studies in a basic training population (20% of participants) with the lowest proportion of women in intervention trials (6% of participants). These data suggest women are not under-represented in military musculoskeletal injury studies when considering the gender representation of most militaries. Our data are, however, biased by large epidemiological trials and women were under-represented in intervention trials. The under-representation of women in intervention trials could be due to difficulties in controlling for the effects of female sex steroids on musculoskeletal outcomes, or a focus on interventions in the most arduous military roles where injury risk is highest and women have been previously excluded.


Asunto(s)
Personal Militar , Enfermedades Musculoesqueléticas , Humanos , Masculino , Femenino , Enfermedades Musculoesqueléticas/epidemiología , Factores de Riesgo
3.
J Dent Res ; 98(8): 896-903, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31189369

RESUMEN

Oral cancers, primarily squamous cell carcinomas (SCCs), progress either slowly or aggressively. Here we assessed the role of macrophages in SCC behavior. We used mouse SCC cells derived from tumors harboring a KrasG12D activation mutation and Smad4 deletion in keratin 15-positive stem cells and a human oral SCC cell line, FaDu, which has NRAS amplification and SMAD4 deletion. SCC cells were transplanted into immune-compromised or immune-competent (syngeneic) recipients. After tumors were established, we used clodronate liposomes to ablate macrophages. We found that the number of tumor-associated macrophages (TAMs) was not affected by the presence of T cells but differed considerably among tumors derived from different SCC lines. Clodronate significantly reduced TAMs and splenic macrophages, resulting in reduced SCC volumes. Tumors with clodronate treatment did not show decreased proliferation but did exhibit increased apoptosis and reduced vascular density. FLIP (Fas-associated via death domain-like interleukin 1ß-converting enzyme inhibitory protein), an apoptosis inhibitor abundantly produced in tumor cells and TAMs, was reduced in tumor cells of clodronate-treated mice. Reduced FLIP levels correlated with reductions in phosphorylated nuclear NFκB p65 and NFκB inhibitor attenuated FLIP protein levels in SCC cells. Furthermore, TGFß1 serum levels and pSmad3 were reduced in clodronate-treated mice, but their reductions were insufficient to reverse epithelial-mesenchymal transition or TGFß-mediated angiogenesis in endothelial cells. Consequently, metastasis was not significantly reduced by macrophage reduction. However, reduced pSmad3 correlated with reduction of its transcriptional target, vascular endothelial growth factor A, in clodronate-treated tumor cells, which correlated with reduced vascular density in clodronate-treated tumors. Taken together, our study revealed that macrophages contribute to SCC expansion through interactions with tumor cells but are dispensable for SCC metastasis. Our study provides novel insights into understanding the contributions and limitations of TAMs in SCC progression.


Asunto(s)
Carcinoma de Células Escamosas/inmunología , Macrófagos/inmunología , Linfocitos T/inmunología , Animales , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , Ácido Clodrónico/farmacología , Femenino , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Desnudos
4.
J Dent Res ; 97(6): 683-690, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29649368

RESUMEN

Model systems for oral cancer research have progressed from tumor epithelial cell cultures to in vivo systems that mimic oral cancer genetics, pathological characteristics, and tumor-stroma interactions of oral cancer patients. In the era of cancer immunotherapy, it is imperative to use model systems to test oral cancer prevention and therapeutic interventions in the presence of an immune system and to discover mechanisms of stromal contributions to oral cancer carcinogenesis. Here, we review in vivo mouse model systems commonly used for studying oral cancer and discuss the impact these models are having in advancing basic mechanisms, chemoprevention, and therapeutic intervention of oral cancer while highlighting recent discoveries concerning the role of immune cells in oral cancer. Improvements to in vivo model systems that highly recapitulate human oral cancer hold the key to identifying features of oral cancer initiation, progression, and invasion as well as molecular and cellular targets for prevention, therapeutic response, and immunotherapy development.


Asunto(s)
Modelos Animales de Enfermedad , Inmunoterapia , Neoplasias de la Boca/terapia , Animales , Ratones , Neoplasias de la Boca/inmunología
5.
J Colloid Interface Sci ; 509: 94-101, 2018 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-28886373

RESUMEN

HYPOTHESIS: The ability to identify the stress-strain relations correctly is critical to understanding and modeling any rheological responses of an interface. Langmuir-Pockels (LP) trough is one of the most commonly used tools for studying an interface. Most, if not all, existing studies assume a 1D uniaxial compression during a LP-trough compression experiment. It is hypothesized that the deformation field is far more complex than what is typically assumed. EXPERIMENTS: To examine this hypothesis, we custom-built a glass-bottomed LP trough equipped with a camera to capture a series of optical images asa carbon nanotube (CNT)-laden interface is compressed. A digital image correlation (DIC) technique was then applied to the images to evaluate the global strain field during compression of the CNT laden interface. The DIC-corrected strain data were subsequently analyzed with the surface stress data to quantify the surface shear and dilatational moduli of the CNT-laden interface. FINDINGS: Our experimental findings clearly show, for the first time, the development of a non-uniform and complex 2D strain field during compression. The local strains were further quantified and compared with the usual assumption of 1D uniaxial compression. Although the compressive strain averaged over the whole trough area closely resembles the 1D uniaxial compression strain, the 1D compression assumption underestimates the local strain by about 36% at the center of the trough, where the surface stresses are measured. This is the first study in applying the DIC technique to map out the global strain field asa particle-laden interface is compressed. The method may also be applicable to other systems with similar optical texture, allowing the correct identification of stress-strain relationship of an interface.

7.
Genetics ; 156(4): 1573-84, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11102358

RESUMEN

The Aspergillus nidulans NIMX(CDC2) protein kinase has been shown to be required for both the G(2)/M and G(1)/S transitions, and recent evidence has implicated a role for NIMX(CDC2) in septation and conidiation. While much is understood of its G(2)/M function, little is known about the functions of NIMX(CDC2) during G(1)/S, septation, and conidiophore development. In an attempt to better understand how NIMX(CDC2) is involved in these processes, we have isolated four extragenic suppressors of the A. nidulans nimX2(cdc2) temperature-sensitive mutation. Mutation of these suppressor genes, designated snxA-snxD for suppressor of nimX, affects nuclear division, septation, and conidiation. The cold-sensitive snxA1 mutation leads to arrest of nuclear division during G(1) or early S. snxB1 causes hyperseptation in the hyphae and sensitivity to hydroxyurea, while snxC1 causes septation in the conidiophore stalk and aberrant conidiophore structure. snxD1 leads to slight septation defects and hydroxyurea sensitivity. The additional phenotypes that result from the suppressor mutations provide genetic evidence that NIMX(CDC2) affects septation and conidiation in addition to nuclear division, and cloning and biochemical analysis of these will allow a better understanding of the role of NIMX(CDC2) in these processes.


Asunto(s)
Aspergillus nidulans/genética , Ciclinas/genética , Proteínas Fúngicas/genética , Genes Fúngicos , Genes Supresores , Aspergillus nidulans/citología , Aspergillus nidulans/enzimología , Ciclinas/fisiología , Proteínas Fúngicas/fisiología
8.
J Biol Rhythms ; 8(2): 107-24, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8369548

RESUMEN

The electroretinogram (ERG) was recorded from free-moving Anolis lizards once per hour for 5 days. As in our previous work, the b-wave, but not the a-wave, showed a reliable circadian rhythm (CR) in amplitude, with an acrophase near projected noon. Both the a- and b-waves showed a CR in peak time (implicit time, or IT), with the a-wave IT being longest near midnight, and the b-wave IT at midday. Acrophases were shifted when animals were housed on a phase-shifted light-dark cycle. The ERG CR was unaffected by removal of the parietal organ, but it was virtually abolished by removal of the pineal gland, thus suggesting that pineal output (probably melatonin) modulates retinal responses. In addition to the ERG, the tectal light-evoked potential exhibited a CR--a finding compatible with a circadian variation in retinal output. Lastly, the amplitude of the ERG component waveforms showed a seasonal variation, but the ERG CR was constant across the year.


Asunto(s)
Ritmo Circadiano/fisiología , Lagartos/fisiología , Glándula Pineal/fisiología , Retina/fisiología , Animales , Electrorretinografía , Potenciales Evocados , Lóbulo Parietal/fisiología , Lóbulo Parietal/cirugía , Glándula Pineal/cirugía , Estaciones del Año , Techo del Mesencéfalo/fisiología
9.
Neuropsychopharmacology ; 19(1): 99-103, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9608582

RESUMEN

Several products of the hepatic metabolism of clozapine are found in high concentrations in the plasma of schizophrenic patients treated with this atypical antipsychotic drug. One of these metabolites, N-desmethylclozapine, has substantially different affinities for dopamine and serotonin metabolites than does the parent compound. However, it is not known if this metabolite is active in vivo. We examined the effect of acute administration of desmethylclozapine to rats on forebrain Fos protein expression. Clozapine induces expression of this immediate-early gene in a distinct regional pattern in the brain. Desmethylclozapine significantly increased Fos protein expression in the medial prefrontal cortex and nucleus accumbens, but not in the dorsolateral striatum, thus mirroring the effects of the parent compound. These data indicate that the desmethyl metabolite of clozapine has in vivo biological activity.


Asunto(s)
Clozapina/análogos & derivados , Prosencéfalo/efectos de los fármacos , Proteínas Proto-Oncogénicas c-fos/biosíntesis , Animales , Western Blotting , Clozapina/farmacología , Masculino , Prosencéfalo/metabolismo , Ratas , Ratas Sprague-Dawley
10.
Hum Pathol ; 15(2): 193-4, 1984 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-6321321

RESUMEN

Granular cell myoblastoma is an uncommon benign tumor. Most cases of endobronchial involvement are detected as they become symptomatic. Multiple tumors of the bronchial tree are quite rare, having been reported infrequently in the English literature. The authors report a case with two-year follow-up, which is unique in that the tumors were asymptomatic and were discovered incidentally at bronchoscopy.


Asunto(s)
Neoplasias de los Bronquios/diagnóstico , Neoplasias de Tejido Muscular/diagnóstico , Neoplasias de los Bronquios/patología , Broncoscopía , Núcleo Celular/patología , Citoplasma/patología , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de Tejido Muscular/patología
11.
Biomaterials ; 19(19): 1745-52, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9856585

RESUMEN

Membranes of pHEMA-based composites were manufactured by adding various kinds of weaved and knitted fabrics and fibers into a deionized water solution of HEMA monomer, EGDMA cross-linker and BIE initiator, and followed by polymerization under ultraviolet radiation. By varying the amount of initial water addition (IWA), the dimensional change of pHEMA matrix from the newly fabricated state to the eventually swollen state could be adjusted to reduce the swellability mismatch with the fabrics and the possibility of the swollen membranes becoming folded and curled was avoided. Mechanical properties of the fiber-reinforced pHEMA composites, including yielding strength, maximum strength, Young's modulus and elongation at break, are improved evidently depending on the mechanical characteristics of additives applied. The involvement of fabrics and fibers in the soft pHEMA matrix also provides an alternative of making the ultra-thin membranes to overcome the problem of easily being torn during handling. In addition, some of these membranes also exhibit an improvement in water transmission rate.


Asunto(s)
Materiales Biocompatibles , Polihidroxietil Metacrilato , Piel Artificial , Fenómenos Biomecánicos , Hidrogeles , Membranas Artificiales
12.
Psychopharmacology (Berl) ; 144(3): 255-63, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10435392

RESUMEN

RATIONALE: Acute administration of typical antipsychotic drugs, such as haloperidol, results in the induction of the immediate-early gene c-fos in the dorsolateral striatum. In contrast, the atypical antipsychotic drug clozapine, which lacks significant extrapyramidal side effect liability, does not induce Fos protein in the dorsal striatum. Several studies have attempted to define the mechanisms through which typical antipsychotic drugs induce striatal Fos, often by pretreating animals with specific receptor antagonists. Despite the broad receptor profile of clozapine, there has been no study of the effect of clozapine pretreatment on haloperidol-elicited striatal Fos expression. METHODS: We examined the effects of clozapine pretreatment of rats on haloperidol-elicited forebrain Fos expression, using both immunoblot and immunohistochemical methods. The effects of clozapine pretreatment were assessed in the dorsal striatum and in the different nucleus accumbens compartments, the septum, and the prefrontal cortex. RESULTS: Clozapine pretreatment markedly decreased haloperidol-elicited striatal Fos induction and blocked haloperidol-induced catalepsy. Clozapine also attenuated haloperidol-elicited Fos expression in the nucleus accumbens, but in the prefrontal cortex and ventrolateral septum the effects of haloperidol and clozapine were additive. CONCLUSIONS: An emerging body of literature suggests a high incidence of rapid relapse in schizophrenic patients when clozapine treatment is discontinued. This psychosis is relatively resistant to haloperidol and other neuroleptics, even in patients who had previously responded well to neuroleptics. The present data may shed light on the central sites associated with and perhaps model certain aspects of the relapse associated with clozapine discontinuation.


Asunto(s)
Clozapina/farmacología , Haloperidol/farmacología , Proteínas Oncogénicas v-fos/biosíntesis , Prosencéfalo/efectos de los fármacos , Antagonistas de la Serotonina/farmacología , Animales , Catalepsia/inducido químicamente , Interacciones Farmacológicas , Haloperidol/efectos adversos , Immunoblotting , Inmunohistoquímica , Prosencéfalo/metabolismo , Ratas , Ratas Sprague-Dawley , Antagonistas de la Serotonina/efectos adversos
13.
Pharmacol Biochem Behav ; 60(3): 753-8, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9678661

RESUMEN

The brain circuitry that subserves the augmented locomotor response to repeated psychostimulant administration has been the subject of intense scrutiny. The dopaminergic innervation of the nucleus accumbens is critically involved in psychostimulant-elicited behavioral sensitization, and recent studies suggest that lesions of structures that send glutamatergic projections to the nucleus accumbens alter the acquisition or expression of psychostimulant-elicited sensitization. Although certain thalamic nuclei provide a major glutamatergic input to the striatum, the involvement of the thalamus in psychostimulant-elicited sensitization has not been investigated. We therefore examined the effects of lesions of the thalamic paraventricular nucleus, which projects to the shell of the nucleus accumbens, on cocaine-elicited locomotor sensitization. Lesions of the paraventricular nucleus did not alter basal locomotor activity, but significantly enhanced the acute locomotor response to cocaine. In contrast, repeated cocaine administration did not progressively augment locomotor activity in lesioned rats, but did so in sham-lesioned animals. The thalamic lesions also blocked the conditioned locomotor response to the environment in which the cocaine injections took place. These data suggest that the thalamic paraventricular nucleus may be an integral part of extended circuitry that subserves both the conditioned and nonconditioned components of psychostimulant-induced behavioral sensitization.


Asunto(s)
Cocaína/farmacología , Actividad Motora/efectos de los fármacos , Narcóticos/farmacología , Núcleos Talámicos/fisiología , Animales , Condicionamiento Psicológico/efectos de los fármacos , Masculino , Ratas , Ratas Sprague-Dawley
14.
J Pharm Biomed Anal ; 15(8): 1197-205, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9215973

RESUMEN

A simple, rapid and accurate method for simultaneous determination of amoxycillin and clavulanic acid using HPLC with beta-cyclodextrin stationary phase was developed. It involves the use of tetraethylammonium acetate (TEAA) as an additive reagent, methanol-buffer solution (pH 4.5) (35:65; v/v) as the mobile phase, detection at 225 mm and chromatogram within 12 min. Linearity and precision of the internal standard method have been obtained. Recoveries ranged from 99.25 to 105.63% for amoxycillin in the synthetic mixture. For clavulanic acid it was from 99.50 to 101.64%. This method is convenient and reproducible for analyses of these two components in different dosage forms.


Asunto(s)
Quimioterapia Combinada/análisis , beta-Ciclodextrinas , Amoxicilina/análisis , Combinación Amoxicilina-Clavulanato de Potasio , Tampones (Química) , Cromatografía Líquida de Alta Presión , Ácidos Clavulánicos/análisis , Ciclodextrinas , Formas de Dosificación , Concentración de Iones de Hidrógeno , Espectrofotometría Ultravioleta
15.
J Gen Psychol ; 120(1): 73-81, 1993 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8340787

RESUMEN

We address inconsistencies in two areas concerning who was first to electrically stimulate a human's brain. First, Boring (1950) and others attributed priority to Eduard Hitzig based on information mentioned somewhat incidentally in Fritsch and Hitzig's (1870) classic work using dogs. Others cited Fritsch and Hitzig but attributed priority to Roberts Bartholow (1874). Second, our examination of translations of Fritsch and Hitzig, especially of footnote 16 in Hitzig's report (1870) of a human case, revealed errors, omissions, and inconsistencies. To aid our inquiry, we requested and received new translations of footnote 16 and of Hitzig's report.


Asunto(s)
Encéfalo/fisiología , Estimulación Eléctrica , Corteza Cerebral/fisiología , Femenino , Historia del Siglo XIX , Historia del Siglo XX , Humanos , Masculino , Neurofisiología/historia
16.
BJA Educ ; 19(7): 232-237, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33456896
18.
Vet Rec ; 105(25-26): 581-2, 1979.
Artículo en Inglés | MEDLINE | ID: mdl-532079
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