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1.
Vet Pathol ; 59(2): 310-318, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34974772

RESUMEN

Twelve cases of adult-onset blindness were identified in a flock of 130 polled Wiltshire sheep in New Zealand over a 3-year period. Affected sheep developed night blindness between 2 and 3 years of age, which progressed to complete blindness by 4 to 5 years of age. Fundic examination findings included progressive tapetal hyperreflectivity and attenuation of retinal blood vessels. Histologically, the retinas had a selective loss of rod photoreceptors with initial preservation of cone photoreceptors. Retinal degeneration was not accompanied by any other ocular or central nervous system abnormalities, and pedigree analysis suggested an inherited basis for the disease. Mating an affected Wiltshire ram to 2 affected Wiltshire ewes resulted in 6 progeny that all developed retinal degeneration by 2 years of age, while mating of the same affected ram to 6 unaffected ewes resulted in 8 unaffected progeny, consistent with autosomal recessive inheritance. Homozygosity mapping of 5 affected Wiltshire sheep and 1 unaffected Wiltshire sheep using an OvineSNP50 Genotyping BeadChip revealed an identical-by-descent region on chromosome 5, but none of the genes within this region were considered plausible candidate genes. Whole-genome sequencing of 2 affected sheep did not reveal any significant mutations in any of the genes associated with retinitis pigmentosa in humans or progressive retinal atrophy in dogs. Inherited progressive retinal degeneration affecting rod photoreceptors has not been previously reported in sheep, but this disease has several similarities to inherited retinal dystrophies in other species.


Asunto(s)
Ceguera Nocturna , Degeneración Retiniana , Retinitis Pigmentosa , Enfermedades de las Ovejas , Animales , Perros , Femenino , Masculino , Ceguera Nocturna/genética , Ceguera Nocturna/patología , Ceguera Nocturna/veterinaria , Linaje , Retina/patología , Degeneración Retiniana/genética , Degeneración Retiniana/patología , Degeneración Retiniana/veterinaria , Retinitis Pigmentosa/genética , Retinitis Pigmentosa/patología , Retinitis Pigmentosa/veterinaria , Ovinos , Enfermedades de las Ovejas/genética , Enfermedades de las Ovejas/patología
2.
Exp Eye Res ; 207: 108600, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33930398

RESUMEN

Neuronal ceroid lipofuscinoses (NCL; Batten disease) are a group of inherited neurodegenerative diseases primarily affecting children. A common feature across most NCLs is the progressive loss of vision. We performed intravitreal injections of self-complementary AAV9 vectors packaged with either ovine CLN5 or CLN6 into one eye of 3-month-old CLN5-/- or CLN6-/- animals, respectively. Electroretinography (ERG) was performed every month following treatment, and retinal histology was assessed post-mortem in the treated compared to untreated eye. In CLN5-/- animals, ERG amplitudes were normalised in the treated eye whilst the untreated eye declined in a similar manner to CLN5 affected controls. In CLN6-/- animals, ERG amplitudes in both eyes declined over time although the treated eye showed a slower decline. Post-mortem examination revealed significant attenuation of retinal atrophy and lysosomal storage body accumulation in the treated eye compared with the untreated eye in CLN5-/- animals. This proof-of-concept study provides the first observation of efficacious intravitreal gene therapy in a large animal model of NCL. In particular, the single administration of AAV9-mediated intravitreal gene therapy can successfully ameliorate retinal deficits in CLN5-/- sheep. Combining ocular gene therapy with brain-directed therapy presents a promising treatment strategy to be used in future sheep trials aiming to halt neurological and retinal disease in CLN5 Batten disease.


Asunto(s)
Terapia Genética/métodos , Proteínas de Membrana de los Lisosomas/genética , Lipofuscinosis Ceroideas Neuronales/terapia , Degeneración Retiniana/terapia , Animales , Dependovirus/genética , Modelos Animales de Enfermedad , Electrorretinografía , Femenino , Vectores Genéticos , Proteína Ácida Fibrilar de la Glía/metabolismo , Inyecciones Intravítreas , Proteína 1 de la Membrana Asociada a los Lisosomas/metabolismo , Lipofuscinosis Ceroideas Neuronales/metabolismo , Lipofuscinosis Ceroideas Neuronales/fisiopatología , Retina/metabolismo , Retina/fisiopatología , Degeneración Retiniana/metabolismo , Degeneración Retiniana/fisiopatología , Ovinos
3.
Evol Anthropol ; 28(2): 86-99, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30869833

RESUMEN

Humans frequently perform extravagant and seemingly costly behaviors, such as widely sharing hunted resources, erecting conspicuous monumental structures, and performing dramatic acts of religious devotion. Evolutionary anthropologists and archeologists have used signaling theory to explain the function of such displays, drawing inspiration from behavioral ecology, economics, and the social sciences. While signaling theory is broadly aimed at explaining honest communication, it has come to be strongly associated with the handicap principle, which proposes that such costly extravagance is in fact an adaptation for signal reliability. Most empirical studies of signaling theory have focused on obviously costly acts, and consequently anthropologists have likely overlooked a wide range of signals that also promote reliable communication. Here, we build on recent developments in signaling theory and animal communication, developing an updated framework that highlights the diversity of signal contents, costs, contexts, and reliability mechanisms present within human signaling systems. By broadening the perspective of signaling theory in human systems, we strive to identify promising areas for further empirical and theoretical work.


Asunto(s)
Evolución Biológica , Comunicación , Animales , Antropología Física , Conducta Apetitiva/fisiología , Conducta Ceremonial , Etnicidad , Humanos , Religión
4.
Am Nat ; 183(2): 199-213, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24464195

RESUMEN

Limited resources lead animals into conflicts of interest, which are resolved when an individual withdraws from a direct contest. Current theory suggests that the decision to withdraw can be based on a threshold derived from an individual's own state (self-assessment) or on a comparison between their own state and their opponent's (mutual assessment). The observed variation between these assessment strategies in nature does not conform to theory. Thus, we require theoretical developments that explain the functional significance of different assessment strategies. We consider a hawk-dove game with two discrete classes that differ in fighting ability, in which the players strategically decide on their investment toward mutual assessment. Analysis of the model indicates that there are simultaneous trade-offs relating to assessment strategies. First, weak individuals in a population must decide on whether to acquire information about their opponents at the cost of providing opponents with information about themselves. Secondly, all individuals must decide between investing in mutual assessment and being persistent in contests. Our analysis suggests that the potential for individuals to make errors during contests and differences in the consequences of sharing information within a population may serve as fundamental concepts for explaining variation in assessment strategy.


Asunto(s)
Conducta Animal , Conducta Competitiva , Modelos Biológicos , Comunicación Animal , Animales , Evolución Biológica
5.
J Clin Med ; 12(5)2023 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-36902800

RESUMEN

Middle segment-preserving pancreatectomy (MPP) can treat multilocular diseases in the pancreatic head and tail while avoiding impairments caused by total pancreatectomy (TP). We conducted a systematic literature review of MPP cases and collected individual patient data (IPD). MPP patients (N = 29) were analyzed and compared to a group of TP patients (N = 14) in terms of clinical baseline characteristics, intraoperative course, and postoperative outcomes. We also conducted a limited survival analysis following MPP. Pancreatic functionality was better preserved following MPP than TP, as new-onset diabetes and exocrine insufficiency each occurred in 29% of MPP patients compared to near-ubiquitous prevalence among TP patients. Nevertheless, POPF Grade B occurred in 54% of MPP patients, a complication avoidable with TP. Longer pancreatic remnants were a prognostic indicator for shorter and less eventful hospital stays with fewer complications, whereas complications of endocrine functionality were associated with older patients. Long-term survival prospects after MPP appeared strong (median up to 110 months), but survival was lower in cases with recurring malignancies and metastases (median < 40 months). This study demonstrates MPP is a feasible treatment alternative to TP for selected cases because it can avoid pancreoprivic impairments, but at the risk of perioperative morbidity.

6.
Cancers (Basel) ; 14(1)2021 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-35008223

RESUMEN

Guidelines do not recommend resection surgery for oligometastatic pancreatic ductal adenocarcinoma (PDAC). However, reports in small samples of selected patients suggest that surgery extends survival. Thus, this study aims to gather evidence for the benefits of cancer-directed surgery (CDS) by analyzing a national cohort and identifying prognostic factors that aid the selection of candidates for CDS or recruitment into experimental trials. Data for patients with PDAC and hepatic metastasis were extracted from the population-based Surveillance, Epidemiology, and End Results database (SEER). The bias between CDS and non-CDS groups was minimized with Propensity Score Matching (PSM), and the prognostic role of CDS was investigated by comparing Kaplan-Meier estimators and Cox proportional hazard models. A total of 12,018 patients were extracted from the database, including 259 patients who underwent CDS that were 1:1 propensity score-matched with patients who did not receive CDS. CDS appeared to significantly prolong median overall survival from 5 to 10 months. Multivariate analysis revealed chemotherapy as a protective prognostic, whilst survival was impaired by old age and tumors that were poorly differentiated (Grades III-IV). These factors can be used to select patients likely to benefit from CDS treatment, which may facilitate recruitment into randomized controlled trials.

7.
PLoS One ; 13(5): e0197280, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29847591

RESUMEN

Research shows that gender inequality is still a major issue in academic science, yet academic societies may serve as underappreciated and effective avenues for promoting female leadership. That is, society membership is often self-selective, and board positions are elected (with a high turnover compared to institutions)-these characteristics, among others, may thus create an environment conducive to gender equality. We therefore investigate this potential using an information-theoretic approach to quantify gender equality (male:female ratios) in zoology society boards around the world. We compare alternative models to analyze how society characteristics might predict or correlate with the proportion of female leaders, and find that a cultural model, including society age, size of board and whether or not a society had an outward commitment or statement of equality, was the most informative predictor for the gender ratio of society boards and leadership positions. This model was more informative than alternatives that considered, for instance, geographic location, discipline of study or taxonomic focus. While women were more highly represented in society leadership than in institutional academic leadership, this representation was still far short of equal (~30%): we thus also provide a checklist and recommendations for societies to contribute to global gender equality in science.


Asunto(s)
Liderazgo , Sociedades Científicas , Cultura , Femenino , Humanos , Teoría de la Información , Masculino , Sexismo , Zoología
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