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1.
Nature ; 605(7908): 76-83, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35508775

RESUMEN

Living cilia stir, sweep and steer via swirling strokes of complex bending and twisting, paired with distinct reverse arcs1,2. Efforts to mimic such dynamics synthetically rely on multimaterial designs but face limits to programming arbitrary motions or diverse behaviours in one structure3-8. Here we show how diverse, complex, non-reciprocal, stroke-like trajectories emerge in a single-material system through self-regulation. When a micropost composed of photoresponsive liquid crystal elastomer with mesogens aligned oblique to the structure axis is exposed to a static light source, dynamic dances evolve as light initiates a travelling order-to-disorder transition front, transiently turning the structure into a complex evolving bimorph that twists and bends via multilevel opto-chemo-mechanical feedback. As captured by our theoretical model, the travelling front continuously reorients the molecular, geometric and illumination axes relative to each other, yielding pathways composed from series of twisting, bending, photophobic and phototropic motions. Guided by the model, here we choreograph a wide range of trajectories by tailoring parameters, including illumination angle, light intensity, molecular anisotropy, microstructure geometry, temperature and irradiation intervals and duration. We further show how this opto-chemo-mechanical self-regulation serves as a foundation for creating self-organizing deformation patterns in closely spaced microstructure arrays via light-mediated interpost communication, as well as complex motions of jointed microstructures, with broad implications for autonomous multimodal actuators in areas such as soft robotics7,9,10, biomedical devices11,12 and energy transduction materials13, and for fundamental understanding of self-regulated systems14,15.

2.
Nature ; 592(7854): 386-391, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33854248

RESUMEN

The fundamental topology of cellular structures-the location, number and connectivity of nodes and compartments-can profoundly affect their acoustic1-4, electrical5, chemical6,7, mechanical8-10 and optical11 properties, as well as heat1,12, fluid13,14 and particle transport15. Approaches that harness swelling16-18, electromagnetic actuation19,20 and mechanical instabilities21-23 in cellular materials have enabled a variety of interesting wall deformations and compartment shape alterations, but the resulting structures generally preserve the defining connectivity features of the initial topology. Achieving topological transformation presents a distinct challenge for existing strategies: it requires complex reorganization, repacking, and coordinated bending, stretching and folding, particularly around each node, where elastic resistance is highest owing to connectivity. Here we introduce a two-tiered dynamic strategy that achieves systematic reversible transformations of the fundamental topology of cellular microstructures, which can be applied to a wide range of materials and geometries. Our approach requires only exposing the structure to a selected liquid that is able to first infiltrate and plasticize the material at the molecular scale, and then, upon evaporation, form a network of localized capillary forces at the architectural scale that 'zip' the edges of the softened lattice into a new topological structure, which subsequently restiffens and remains kinetically trapped. Reversibility is induced by applying a mixture of liquids that act separately at the molecular and architectural scales (thus offering modular temporal control over the softening-evaporation-stiffening sequence) to restore the original topology or provide access to intermediate modes. Guided by a generalized theoretical model that connects cellular geometries, material stiffness and capillary forces, we demonstrate programmed reversible topological transformations of various lattice geometries and responsive materials that undergo fast global or localized deformations. We then harness dynamic topologies to develop active surfaces with information encryption, selective particle trapping and bubble release, as well as tunable mechanical, chemical and acoustic properties.

3.
Ann Oncol ; 34(9): 813-825, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37330052

RESUMEN

BACKGROUND: The isolation of cell-free DNA (cfDNA) from the bloodstream can be used to detect and analyze somatic alterations in circulating tumor DNA (ctDNA), and multiple cfDNA-targeted sequencing panels are now commercially available for Food and Drug Administration (FDA)-approved biomarker indications to guide treatment. More recently, cfDNA fragmentation patterns have emerged as a tool to infer epigenomic and transcriptomic information. However, most of these analyses used whole-genome sequencing, which is insufficient to identify FDA-approved biomarker indications in a cost-effective manner. PATIENTS AND METHODS: We used machine learning models of fragmentation patterns at the first coding exon in standard targeted cancer gene cfDNA sequencing panels to distinguish between cancer and non-cancer patients, as well as the specific tumor type and subtype. We assessed this approach in two independent cohorts: a published cohort from GRAIL (breast, lung, and prostate cancers, non-cancer, n = 198) and an institutional cohort from the University of Wisconsin (UW; breast, lung, prostate, bladder cancers, n = 320). Each cohort was split 70%/30% into training and validation sets. RESULTS: In the UW cohort, training cross-validated accuracy was 82.1%, and accuracy in the independent validation cohort was 86.6% despite a median ctDNA fraction of only 0.06. In the GRAIL cohort, to assess how this approach performs in very low ctDNA fractions, training and independent validation were split based on ctDNA fraction. Training cross-validated accuracy was 80.6%, and accuracy in the independent validation cohort was 76.3%. In the validation cohort where the ctDNA fractions were all <0.05 and as low as 0.0003, the cancer versus non-cancer area under the curve was 0.99. CONCLUSIONS: To our knowledge, this is the first study to demonstrate that sequencing from targeted cfDNA panels can be utilized to analyze fragmentation patterns to classify cancer types, dramatically expanding the potential capabilities of existing clinically used panels at minimal additional cost.


Asunto(s)
Ácidos Nucleicos Libres de Células , ADN Tumoral Circulante , Neoplasias de la Próstata , Masculino , Humanos , ADN Tumoral Circulante/genética , Mutación , Neoplasias de la Próstata/genética , Ácidos Nucleicos Libres de Células/genética , Perfilación de la Expresión Génica , Biomarcadores de Tumor/genética
4.
N Z Vet J ; 68(4): 231-237, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31852374

RESUMEN

Case history: A 2-year-old Rottweiler dog from Perth (WA, Australia) was referred for assessment of a chronic productive cough and weight loss.Clinical findings: Severely enlarged bilateral superficial cervical lymph nodes and severely enlarged abdominal organs were present. The body condition score was poor and there was moderate muscle wasting. Thoracic and abdominal computed tomography images revealed severe diffuse enlargement of thoracic and abdominal lymph nodes, hepatomegaly and diffuse splenomegaly. A diffuse bronchial pattern with severe multifocal saccular bronchiectasis was identified in the lungs.Diagnostic findings: Fungal organisms were seen within macrophages on cytological preparations and on histopathological sections of biopsies of the superficial cervical lymph node. Macrophages contained intracytoplasmic, non-filamentous round-to-ovoid organisms, which varied in size from 5-30 µm in diameter with variable morphology. Budding was not observed, and no hyphae were present. Fungal culture of lymph node tissue resulted in growth of Aspergillus (Phialosimplex) caninus which was confirmed by amplification and sequencing of a segment of the 16S-23S rRNA internal transcribed spacer. Concurrent bacterial bronchitis was diagnosed on culture of broncho-alveolar fluid.Diagnosis: Disseminated aspergillosis caused by Aspergillus caninus.Clinical relevance: This is believed to be the first report of infection caused by A. caninus in a dog in Australasia. The dog was treated with itraconazole for 7 months and was still alive 7 months after the start of treatment.


Asunto(s)
Antifúngicos/uso terapéutico , Aspergilosis/veterinaria , Aspergillus/aislamiento & purificación , Enfermedades de los Perros/microbiología , Itraconazol/uso terapéutico , Animales , Aspergilosis/tratamiento farmacológico , Aspergilosis/epidemiología , Aspergilosis/microbiología , Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Enfermedad Hepática Inducida por Sustancias y Drogas/veterinaria , Enfermedades de los Perros/tratamiento farmacológico , Enfermedades de los Perros/epidemiología , Perros , Itraconazol/administración & dosificación , S-Adenosilmetionina/uso terapéutico , Australia Occidental/epidemiología
5.
J Dairy Sci ; 102(10): 9213-9223, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31351728

RESUMEN

Vascular changes play an important role in the pathogenesis of claw horn disruption lesions in cattle. The aim of the study was to measure arterial blood flow in the hind limbs of German Holstein cows with claw horn disruption lesions. A 10-MHz linear transducer was used to assess blood flow in the interdigital artery in the dorsal pastern region in the hind limbs of 11 non-lame and 33 lame German Holstein cows in which lameness was scored clinically. Qualitative and quantitative blood flow parameters were compared in affected limbs and unaffected contralateral hind limbs in lame cows and in the hind limbs of lame cows and non-lame cows. A pulsed-wave Doppler signal suitable for analysis was obtained in 78 of 88 limbs (33 affected and contralateral limbs, 22 limbs of control cows). Blood flow curve types 1 and 2 were predominant in the hind limbs of lame cows. Vessel diameter, end-diastolic velocity, and blood flow rate were significantly greater in lame cows than in non-lame cows and were numerically greater in moderately lame cows than in mildly lame cows. The differences in the qualitative and quantitative parameters between lame and non-lame cows were most likely caused by inflammation of the pododerm. The role of weight distribution between the paired hind limbs and the existence of claw horn disruption appeared to have an effect on the differences in local circulation in the affected and unaffected contralateral hind limbs in lame cows.


Asunto(s)
Enfermedades de los Bovinos/fisiopatología , Enfermedades del Pie/veterinaria , Pezuñas y Garras/irrigación sanguínea , Cojera Animal/fisiopatología , Ultrasonografía Doppler/veterinaria , Animales , Arterias , Bovinos , Femenino , Enfermedades del Pie/fisiopatología , Miembro Posterior/irrigación sanguínea , Flujo Sanguíneo Regional
6.
Reprod Domest Anim ; 53(3): 784-792, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29603438

RESUMEN

Increased concentrations of Anti-Muellerian hormone (AMH) can indicate a granulosa cell tumour as shown in women, mares and cows. To investigate AMH to differentiate canine granulosa cell tumour from other ovarian pathologies, we evaluated the ovaries of 63 bitches. Blood serum samples were collected before surgery for AMH analysis. Ovaries were submitted for histopathological examination. Fourteen bitches showed normal ovaries. These bitches had AMH values between 0.12 and 0.99 ng/ml. In 20 bitches ovarian cysts i.e., follicular cysts (n = 8), corpora lutea cysts (n = 7), subsurface cysts (n = 5) were diagnosed. These dogs had AMH values of 0.11-2.09 ng/ml. Bitches with small luteinized follicular cysts had slightly higher AMH values than those without ovarian alteration. In 29 cases ovarian neoplasms i.e., granulosa cell tumour (n = 9), epithelial tumours (n = 16), dysgerminomas (n = 3) and one sarcoma were identified. Anti-Muellerian hormone values of bitches with an ovarian neoplasm except granulosa cell tumour ranged from 0.18 to 1.18 ng/ml. The AMH values of bitches with granulosa cell tumour ranged from 1.12 to ≤23 ng/ml and were significantly higher (p < .05) than in all of the other bitches. The cut-off of 0.99 ng/ml gave a sensitivity of 100% and a specificity of 94.44% to diagnose granulosa cell tumour. In conclusion, markedly elevated AMH concentrations in bitches are indicative for a granulosa cell tumour. However, negative testing does not rule out the existence of small one. Differentiation of GCT from luteinized follicular cysts may especially be difficult.


Asunto(s)
Hormona Antimülleriana/sangre , Enfermedades de los Perros/sangre , Quistes Ováricos/veterinaria , Neoplasias Ováricas/veterinaria , Animales , Carcinoma/sangre , Carcinoma/veterinaria , Perros , Disgerminoma/sangre , Disgerminoma/veterinaria , Femenino , Tumor de Células de la Granulosa/sangre , Tumor de Células de la Granulosa/diagnóstico , Tumor de Células de la Granulosa/veterinaria , Quistes Ováricos/sangre , Neoplasias Ováricas/sangre , Sarcoma/sangre , Sarcoma/veterinaria
7.
J Anim Physiol Anim Nutr (Berl) ; 102 Suppl 1: 16-23, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29623685

RESUMEN

The aim of the study was to evaluate the clinical efficacy of specific bioactive collagen peptides (BCP), here administered orally as PETAGILE® , on horses with mild to moderate, naturally occurring osteoarthritis. Data from a two-centred pilot study were used for the meta-analysis. Thirty-eight privately owned horses of various breeds were available. In one centre, 18 of these patients (6 ± 3 years; 519 ± 100 kg BW) received either 25 g (n = 6) or 50 g (n = 12) BCP/day orally for 12 weeks. In the second centre, 20 horses (18 ± 4 years; 413 ± 94 kg BW) received either a placebo (control; n = 10) or 25 g BCP/day. The attending veterinarians performed an orthopaedic examination including flexion tests and evaluated the degree of lameness, rotation pain, step length and arc of foot flight during trot (8 parameters) at the beginning and after 6 and 12 weeks. The horse owners answered a weekly questionnaire about their perception of lameness, mobility and the horses' willingness to run. In the 50 g BCP group, in six of eight parameters, a strong effect (Cohen's r > .5) was detected with two parameters (lameness and flexion pain) significantly improved already after 6 weeks. In the 25 g BCP group, a moderate effect (Cohen's r = .3-0.5) was seen in six parameters, with three parameters improved already after 6 weeks. The owners reported a strong effect for mobility and willingness to run (Cohen's r = .69 and .62, respectively) and a moderate effect (Cohen's r = .49 and 0.41) for the development of lameness in the 50 g and 25 g BCP group in comparison with the placebo treatment. This study revealed promising effects of the safe oral-specific BCP supplementation on symptoms of osteoarthritis in horses already after 3 months. The higher dosage of 50 g BCP/day had superior impact. Further long-term investigations on specific BCP efficacy in horses with osteoarthritis, preferably in blinded and placebo-controlled studies, should be performed to confirm these first positive results.


Asunto(s)
Alimentación Animal/análisis , Colágeno/administración & dosificación , Colágeno/química , Suplementos Dietéticos , Enfermedades de los Caballos/dietoterapia , Osteoartritis/veterinaria , Animales , Dieta/veterinaria , Femenino , Caballos , Cojera Animal , Masculino , Osteoartritis/dietoterapia , Proyectos Piloto
8.
Schweiz Arch Tierheilkd ; 160(9): 525-532, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30206048

RESUMEN

INTRODUCTION: The aim of the study was to evaluate the molecular and histological effects of negative pressure wound therapy (NPWT) on vascularisation in clinical cases of open wound treatment in dogs. Open wounds (n=10) were randomly assigned to one of two groups: NPWT treatment (n=5) or foam treatment (polyurethane-foam dressing, n=5). Wounds were matched based on age and underlying cause and analysed with respect to neovascularisation (CD31) and matrix proteinase changes (MMP-9). Histological slides were blinded and analysis was performed using automated histomorphometric software. Values determined at day zero after debridement were used as a reference and wound development at day six was evaluated using linear mixed models. Signalment, pre-treatment time and underlying cause were similar between groups. NPWT resulted in a highly significant increase of vascularisation (p.


INTRODUCTION: Le but de ce travail était de relever les effets moléculaires et histologiques de la thérapie des plaies par pression négative (NPWT) au cours du traitement de plaies ouvertes en clinique chez le chien. Des plaies ouvertes (n=10) ont été répartie de manière randomisée en deux groupes : NPWT (n=5) ou recouvrement au moyen d'un pansement en polyuréthane (n=5). Les plaies ont été appariées en tenant compte de leur âge ainsi que de leur cause et examinées quant à leur néo vascularisation (CD31) et aux variations de l'activité des métalloprotéases matricielles (MMP-9). L'appréciation des divers échantillons histologiques a été faite à l'aveugle, au moyen d'un logiciel d'histomorphométrie automatisé. Les valeurs obtenues au jour 0 après débridement servaient de référence pour l'évolution des plaies au jour 6, évolution analysée avec un modèle mixte. Le signalement, la durée du traitement préalable ainsi que les causes étaient comparables entre les groupes. La NPWT amenait, comparativement au contrôle, à une augmentation significative de la vascularisation (p.


Asunto(s)
Perros/lesiones , Metaloproteinasa 9 de la Matriz/metabolismo , Terapia de Presión Negativa para Heridas/veterinaria , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/metabolismo , Cicatrización de Heridas/fisiología , Animales , Histocitoquímica
9.
BMC Vet Res ; 13(1): 162, 2017 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-28587605

RESUMEN

BACKGROUND: Local circulatory disturbances have been implicated in the development of foot disorders in cattle. The goals of this study were to evaluate the suitability of the interdigital artery in the pastern region in both hind limbs using pulsed-wave (PW) Doppler ultrasonography and to investigate quantitative arterial blood flow variables at that site in dairy cows. An Esaote MyLabOne ultrasound machine with a 10-MHz linear transducer was used to assess blood flow in the interdigital artery in the pastern region in both hind limbs of 22 healthy German Holstein cows. The cows originated from three commercial farms and were restrained in a standing hoof trimming chute without sedation. RESULTS: A PW Doppler signal suitable for analysis was obtained in 17 of 22 cows. The blood flow profiles were categorised into four curve types, and the following quantitative variables were measured in three uniform cardiac cycles: vessel diameter, pulse rate, maximum systolic velocity, maximum diastolic velocity, end-diastolic velocity, reverse velocity, maximum time-averaged mean velocity, blood flow rate, resistance index and persistence index. The measurements did not differ among cows from the three farms. Maximum systolic velocity, vessel diameter and pulse rate did not differ but other variables differed significantly among blood flow profiles. CONCLUSIONS: Differences in weight-bearing are thought to be responsible for the normal variability of blood flow profiles in healthy cows. The scanning technique used in this report for evaluation of blood flow in the interdigital artery appears suitable for further investigations in healthy and in lame cows.


Asunto(s)
Arterias , Miembro Posterior/irrigación sanguínea , Ultrasonografía Doppler de Pulso/veterinaria , Animales , Bovinos , Femenino , Pie/irrigación sanguínea , Flujo Sanguíneo Regional
10.
J Anim Physiol Anim Nutr (Berl) ; 100(3): 464-70, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26344575

RESUMEN

The aim of this study was to establish heart rate as a measure of energy expenditure in large active kennel dogs (28 ± 3 kg bw). Therefore, the heart rate (HR)-oxygen consumption (V˙O2) relationship was analysed in Foxhound-Boxer-Ingelheim-Labrador cross-breds (FBI dogs) at rest and graded levels of exercise on a treadmill up to 60-65% of maximal aerobic capacity. To test for effects of training, HR and V˙O2 were measured in female dogs, before and after a training period, and after an adjacent training pause to test for reversibility of potential effects. Least squares regression was applied to describe the relationship between HR and V˙O2. The applied training had no statistically significant effect on the HR-V˙O2 regression. A general regression line from all data collected was prepared to establish a general predictive equation for energy expenditure from HR in FBI dogs. The regression equation established in this study enables fast estimation of energy requirement for running activity. The equation is valid for large dogs weighing around 30 kg that run at ground level up to 15 km/h with a heart rate maximum of 190 bpm irrespective of the training level.


Asunto(s)
Tamaño Corporal/fisiología , Perros/fisiología , Metabolismo Energético/fisiología , Frecuencia Cardíaca/fisiología , Animales , Femenino
11.
Am J Transplant ; 15(11): 2888-99, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26104383

RESUMEN

Delayed graft function (DGF) results from ischemia-reperfusion injury (IRI) and the generation of reactive oxygen species. We hypothesized that NADPH oxidase 2 (Nox2) plays an important role in pathways leading to DGF. We tested this hypothesis in vitro, in an animal model of IRI using wild type and Nox2(-/-) mice, and in patients with DGF. Under hypoxic conditions, primary tubular epithelial cells from Nox2(-/-) mice had reduced expression of MMP2, vimentin, and HSP27. BUN and creatinine levels were significantly increased in both Nox2(-/-) and WT mice at 4 weeks and 6 months after IRI, suggesting the development of acute and chronic kidney injury. At 4 weeks, kidney fibrosis (α-SMA, picrosirius) and oxidative stress (dihydroethidine, HNE) were significantly reduced in Nox2(-/-) mice, confirming the oxidative and pro-fibrotic effects of Nox2. The molecular signature of IRI using genomic analyses demonstrated a significant decline in hypoxia reponse, oxidative stress, fibrosis, and inflammation in Nox2(-/-) mice. Immunohistochemical analyses of pre-implanatation kidney allograft biopsies from patients with subsequent DGF showed significantly greater Nox2 levels and vascular injury compared with patients without DGF. These studies demonstrate that Nox2 is a modulator of IRI and its absence is associated with reduced inflammation, OS, and fibrosis.


Asunto(s)
Funcionamiento Retardado del Injerto/metabolismo , Trasplante de Riñón/efectos adversos , Glicoproteínas de Membrana/metabolismo , NADPH Oxidasas/metabolismo , ARN Interferente Pequeño/metabolismo , Daño por Reperfusión/metabolismo , Análisis de Varianza , Animales , Biomarcadores/metabolismo , Estudios de Casos y Controles , Funcionamiento Retardado del Injerto/patología , Modelos Animales de Enfermedad , Femenino , Fibrosis/patología , Humanos , Immunoblotting , Inmunohistoquímica , Pruebas de Función Renal , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , NADPH Oxidasa 2 , Nefrectomía/efectos adversos , Nefrectomía/métodos , Estrés Oxidativo/fisiología , Distribución Aleatoria , Especies Reactivas de Oxígeno/metabolismo , Daño por Reperfusión/patología , Estadísticas no Paramétricas
12.
Am J Transplant ; 14(5): 1061-72, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24708533

RESUMEN

Animal models of antibody-mediated rejection (ABMR) may provide important evidence supporting proof of concept. We elicited donor-specific antibodies (DSA) by transfusion of donor blood (Brown Norway RT1(n) ) into a complete mismatch recipient (Lewis RT1(l) ) 3 weeks prior to kidney transplantation. Sensitized recipients had increased anti-donor splenocyte IgG1, IgG2b and IgG2c DSA 1 week after transplantation. Histopathology was consistent with ABMR characterized by diffuse peritubular capillary C4d and moderate microvascular inflammation with peritubular capillaritis + glomerulitis > 2. Immunofluorescence studies of kidney allograft tissue demonstrated a greater CD68/CD3 ratio in sensitized animals, primarily of the M1 (pro-inflammatory) phenotype, consistent with cytokine gene analyses that demonstrated a predominant T helper (TH )1 (interferon-γ, IL-2) profile. Immunoblot analyses confirmed the activation of the M1 macrophage phenotype as interferon regulatory factor 5, inducible nitric oxide synthase and phagocytic NADPH oxidase 2 were significantly up-regulated. Clinical biopsy samples in sensitized patients with acute ABMR confirmed the dominance of M1 macrophage phenotype in humans. Despite the absence of tubulitis, we were unable to exclude the effects of T cell-mediated rejection. These studies suggest that M1 macrophages and TH 1 cytokines play an important role in the pathogenesis of acute mixed rejection in sensitized allograft recipients.


Asunto(s)
Complemento C4b/inmunología , Modelos Animales de Enfermedad , Rechazo de Injerto/etiología , Inflamación/etiología , Isoanticuerpos/inmunología , Trasplante de Riñón , Fragmentos de Péptidos/inmunología , Reacción a la Transfusión , Animales , Western Blotting , Citocinas/genética , Citocinas/metabolismo , Rechazo de Injerto/patología , Humanos , Inflamación/patología , Masculino , ARN Mensajero/genética , Ratas , Ratas Endogámicas BN , Ratas Endogámicas Lew , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Donantes de Tejidos , Trasplante Homólogo
13.
J Anim Physiol Anim Nutr (Berl) ; 98(5): 894-900, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24329611

RESUMEN

Hyperflexion, that is the strong deflection of the horse's head, poll and neck, is a prevalent training technique in equitation. Hyperflexion has come under criticism in recent years for being suspected of affecting the horses' well-being contrary to animal welfare. The goal of the present study is a comparison between the impacts of different poll-neck positions on findings in the upper respiratory tract of ridden horses. For this purpose, video recordings of the larynges of 14 horses were taken using an overground endoscope. The videos were recorded at rest and during three different riding phases: firstly, in a stretching posture, secondly, in a working position and, thirdly, in hyperflexion. A comparison between the analyses of the working position and hyperflexion phases revealed a significant reduction in the laryngeal opening area (p = 0.001) with a value of 8.2 ± 5.0%. Furthermore, other parameters of the larynx evaluated also showed a significant diminishment. These changes did not correlate with the age of the horses or their level of education, and they were independent of the individual anatomical conditions of the poll-neck region. In summary, it can be stated that hyperflexion causes a considerable compression of the larynx.


Asunto(s)
Caballos/anatomía & histología , Caballos/fisiología , Laringe/anatomía & histología , Laringe/fisiología , Estrés Fisiológico/fisiología , Animales , Endoscopía , Femenino , Caballos/psicología , Masculino , Grabación en Video
14.
J Anim Physiol Anim Nutr (Berl) ; 98(5): 901-7, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24329719

RESUMEN

Different head-neck positions (HNPs) are used in equestrian sports and are regarded as desirable for training and competition by riders, judges and trainers. Even though some studies have been indicative of hyperflexion having negative effects on horses, this unnatural position is frequently used. In the present study, the influence of different HNPs on physical and psychological stress parameters in the ridden horse was investigated. Heart rate (HR), heart rate variability (HRV) and blood cortisol levels were measured in 18 horses. Low frequency (LF) and high frequency (HF) are power components in the frequency domain measurement of HRV which show the activity of the sympathetic and parasympathetic nervous system. Values were recorded at rest, while riding with a working HNP and while riding with hyperflexion of the horse's head, neck and poll. In addition, rideability and behaviour during the different investigation stages were evaluated by the rider and by an observer. Neither the HR nor the HRV showed a significant difference between working HNP (HR = 105 ± 22/min; LF/HF = 3.89 ± 5.68; LF = 37.28 ± 10.77%) and hyperflexion (HR = 110 ± 18; LF/HF = 1.94 ± 2.21; LF = 38.39 ± 13.01%). Blood cortisol levels revealed a significant increase comparing working HNP (158 ± 60 nm) and hyperflexion (176 ± 64 nm, p = 0.01). The evaluation of rider and observer resulted in clear changes of rideability and behavioural changes for the worse in all parameters collected between a working HNP and hyperflexion. In conclusion, changes of the cortisol blood level as a physical parameter led to the assumption that hyperflexion of head, neck and poll effects a stress reaction in the horse, and observation of the behaviour illustrates adverse effects on the well-being of horses during hyperflexion.


Asunto(s)
Caballos/anatomía & histología , Caballos/fisiología , Laringe/anatomía & histología , Laringe/fisiología , Estrés Fisiológico/fisiología , Estrés Psicológico , Bienestar del Animal , Animales , Femenino , Caballos/sangre , Caballos/psicología , Hidrocortisona/sangre , Masculino
15.
J Anim Physiol Anim Nutr (Berl) ; 98(3): 497-503, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24033508

RESUMEN

The welfare of an animal is ensured if it is able to fully satisfy its essential species-typical needs in all functional aspects of behaviour. In mink, stereotypies and apathy, internal and/or external injuries as well as increased susceptibility to disease have been known to occur as a result of chronic stress. The non-invasive method of analysing faecal cortisol metabolites (FCM) allows conclusions to be drawn about the stress level in the respective housing system. The objective of this study is to find out how the cortisol metabolites content in the faecal changes with increasing age of the mink under semi-natural housing conditions. Thus, 40 American mink (Neovison vison) were housed in two outdoor enclosures imitating natural conditions. Throughout the entire study (13th to 32nd week of life), faecal samples were collected to measure cortisol metabolites. No differences in FCM concentrations between the two outdoor enclosures were found. In the young mink lower, less fluctuating FCM levels were found than in older animals. After the first faecal collection in the 13th/14th week of life, the level of metabolites decreased slightly (p = 0.032; 17th/18th week). From the 22nd/23rd week onwards until the 30th/31st week, shortly before the animals were pelted, continuously increasing concentrations were then measured. Increasing FCM levels with advancing age of the animals are probably attributable to the onset of sexual maturity and/or the respective season. This has to be taken into account in future studies using this method for assessing welfare and when comparing different mink housing systems.


Asunto(s)
Envejecimiento/fisiología , Heces/química , Vivienda para Animales , Hidrocortisona/química , Visón/fisiología , Bienestar del Animal , Animales , Hidrocortisona/fisiología , Estrés Fisiológico
16.
Res Psychother ; 27(1)2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38497293

RESUMEN

Internationally, there is ongoing concern about accessibility to mental health care and training. The goal of this study was to explore commonalities and differences within models of clinical psychology and psychotherapy in Ontario, Canada, and Lombardia, Italy, respectively, to inform improvements to the accessibility of mental health care and training. Using key informant sampling, we recruited ten students and professionals in Italy and Canada who study or work in psychology for semi-structured interviews. We analyzed the interview content using an inductive approach for thematic analysis within countries and meta-theme analysis across countries. The findings indicated three cross-national meta-themes: the need to integrate evidence with practice, the limited accessibility of training for students and treatment for patients, and the importance of the quality of training programs. Despite some differences regarding the amount of scientific training, personal therapy for trainees, and the prominence of cultural diversity training, Canadian and Italian psychology professionals and students shared experiences of psychotherapy practice and clinical psychology training. The three cross-national meta-themes indicate which issues in training and practice may be relevant worldwide and where to focus resources. The findings can inform international collaborations regarding training model structures that may increase access to psychology training and may increase consensus on professional recognition standards to improve mobility for professionals. These changes could reduce barriers to mental healthcare services for patients.

17.
Am J Transplant ; 12(8): 1997-2007, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22568654

RESUMEN

We hypothesized that Nox2, the classical phagocytic NADPH oxidase, plays an important role in calcineurin inhibitor (CNI)-induced renal fibrosis. We tested this hypothesis in vitro, in animal and in human studies. Cyclosporine A (CsA) and tacrolimus (TAC) were associated with greater levels of Nox2 mRNA and epithelial to mesenchymal transition (EMT) in NRK52E cells. CsA increased Nox2, α-SMA and phosphorylated-p38MAPK, Smad3 and NFκB proteins. Nox2 upregulation and EMT were inhibited in TGF-ß1 knockout cells suggesting that TGF-ß1 is required for Nox2 activation. Fisher344 rats treated with high dose CsA showed increased Nox2 in the tubulointerstitium and greater Nox2, α-SMA, phosphorylated Smad3 and nitrotyrosine by immunoblot analyses. Inhibition of Nox2 by coadministration of apocynin or diphenyleneiodonium was associated with reduced fibrogenesis. We validated these findings by treating wild type and Nox2 null (B6.129S-Cybb(Tm1Din)/J) mice with high dose CsA. Western blot analyses confirmed the absence of Nox2 and significantly lower levels of α-SMA and 4-hydroxynonenal (HNE) in CsA-treated knockout mice. These findings were clinically relevant since Nox2 and α-SMA were increased in the tubulointerstitium of kidneys from 15 liver transplant recipients with biopsy-confirmed chronic CsA or TAC nephrotoxicity. In conclusion, specific Nox2 inhibition strategies may improve chronic CNI nephrotoxicity in solid organ transplantation.


Asunto(s)
Ciclosporina/efectos adversos , Inmunosupresores/efectos adversos , Riñón/efectos de los fármacos , Glicoproteínas de Membrana/fisiología , NADPH Oxidasas/fisiología , Animales , Inhibidores de la Calcineurina , Enfermedad Crónica , Transición Epitelial-Mesenquimal , Humanos , Riñón/metabolismo , Trasplante de Hígado , Masculino , Glicoproteínas de Membrana/genética , NADPH Oxidasa 2 , NADPH Oxidasas/genética , ARN Mensajero/genética , Ratas , Ratas Endogámicas F344 , Reacción en Cadena en Tiempo Real de la Polimerasa , Tacrolimus/farmacología , Factor de Crecimiento Transformador beta1/fisiología
18.
Chem Res Toxicol ; 25(8): 1643-51, 2012 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-22799741

RESUMEN

Metabolic profiling of macrophage metabolic response upon exposure to 4-hydroxynonenal (HNE) demonstrates that HNE does not simply inactivate superoxide-generating enzymes but also could be responsible for the impairment of downfield signaling pathways. Multianalyte microphysiometry (MAMP) was employed to simultaneously measure perturbations in extracellular acidification, lactate production, and oxygen consumption for the examination of aerobic and anaerobic pathways. Combining the activation of oxidative burst with phorbol myristate acetate (PMA) and the immunosuppression with HNE, the complex nature of HNE toxicity was determined to be concentration- and time-dependent. Further analysis was utilized to assess the temporal effect of HNE on reactive oxygen species (ROS) production and on protein kinase C (PKC). Increased levels of HNE with decreasing PKC activity suggest that PKC is a target for HNE adductation prior to oxidative burst. Additionally, localization of PKC to the cell membrane was prevented with the introduction of HNE, demonstrating a consequence of HNE adductation on NADPH activation. The impairment of ROS by HNE suggests that HNE has a greater role in foam cell formation and tissue damage than is already known. Although work has been performed to understand the effect of HNE's regulation of specific signaling pathways, details regarding its involvement in cellular metabolism as a whole are generally unknown. This study examines the impact of HNE on macrophage oxidative burst and identifies PKC as a key protein for HNE suppression and eventual metabolic response.


Asunto(s)
Aldehídos/metabolismo , Aldehídos/química , Aldehídos/toxicidad , Animales , Línea Celular , Técnicas Electroquímicas , Electrodos , Luminol/farmacología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Microscopía Confocal , NADP/química , Proteína Quinasa C/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/efectos de los fármacos , Acetato de Tetradecanoilforbol/farmacología
19.
Biomech Model Mechanobiol ; 21(2): 627-645, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35044525

RESUMEN

The simulation of growth processes within soft biological tissues is of utmost importance for many applications in the medical sector. Within this contribution, we propose a new macroscopic approach for modelling stress-driven volumetric growth occurring in soft tissues. Instead of using the standard approach of a-priori defining the structure of the growth tensor, we postulate the existence of a general growth potential. Such a potential describes all eligible homeostatic stress states that can ultimately be reached as a result of the growth process. Making use of well-established methods from visco-plasticity, the evolution of the growth-related right Cauchy-Green tensor is subsequently defined as a time-dependent associative evolution law with respect to the introduced potential. This approach naturally leads to a formulation that is able to cover both, isotropic and anisotropic growth-related changes in geometry. It furthermore allows the model to flexibly adapt to changing boundary and loading conditions. Besides the theoretical development, we also describe the algorithmic implementation and furthermore compare the newly derived model with a standard formulation of isotropic growth.


Asunto(s)
Modelos Biológicos , Anisotropía , Simulación por Computador , Elasticidad , Análisis de Elementos Finitos , Matemática , Estrés Mecánico
20.
Domest Anim Endocrinol ; 78: 106654, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34509739

RESUMEN

Disorders of sexual development (DSD) may have their origin in alterations of the chromosomal, gonadal or phenotypic sex. Affected animals are usually presented because of ambiguous external genitalia, seldom because of reproductive disorders. Anti-Müllerian hormone (AMH) is secreted in the gonads with higher amounts in males than in females and can be used to identify gonadal tissue in sexually normally developed dogs. The aim of this study was to examine the diagnostic potential of serum AMH to identify testicular tissue in 11 dogs with DSD. The diagnostic procedures applied were: determination of the phenotypic sex (n = 11), genital ultrasound (n = 9), determination of the SRY gene (n = 11), karyogram (n = 6), gonadectomy (n = 11), pathohistology of the gonads (n = 10), serum AMH measurement (n = 11). 39 female dogs described in a previous study and 19 male dogs with a normal spermiogram served as controls for the AMH serum concentrations in sexually intact dogs. The 11 dogs with DSD were classified as 7 XY DSD and 4 XX DSD. Presumptive testes were obtained in 10 dogs and 1 dog had an ovotestis combined with a testis. Mean serum AMH values of the dogs with DSD were significantly higher (P < 0.001) than in male and female controls. The upper limit of the AMH test (≥ 23ng/ml) was reached in 6 dogs. High AMH concentrations have been described previously in cryptorchid dogs. 1 dog with a male phenotype and 2 with a female phenotype had AMH values within the range of the male controls, although all of them had cryptorchid testes. A Poodle, in which epididymis were identified but no definitive gonads, had an AMH concentration of the lower limit of the test (≤ 0.01 ng/ml), comparable to previously described castrated dogs. This study indicates that serum AMH levels are a useful diagnostic tool to identify testicular tissue in dogs with DSD and suggests the possible use of AMH to diagnose testicular dysgenesis.


Asunto(s)
Trastornos del Desarrollo Sexual , Enfermedades de los Perros , Animales , Hormona Antimülleriana , Trastornos del Desarrollo Sexual/diagnóstico , Trastornos del Desarrollo Sexual/genética , Trastornos del Desarrollo Sexual/veterinaria , Enfermedades de los Perros/diagnóstico , Perros , Femenino , Masculino , Testículo
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