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1.
Exp Eye Res ; 241: 109818, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38422787

RESUMO

Down syndrome (DS) is the most common chromosomal disorder in humans. DS is associated with increased prevalence of several ocular sequelae, including characteristic blue-dot cerulean cataract. DS is accompanied by age-dependent accumulation of Alzheimer's disease (AD) amyloid-ß (Aß) peptides and amyloid pathology in the brain and comorbid early-onset Aß amyloidopathy and colocalizing cataracts in the lens. Quasi-elastic light scattering (QLS) is an established optical technique that noninvasively measures changes in protein size distributions in the human lens in vivo. In this cross-sectional study, lenticular QLS correlation time was decreased in adolescent subjects with DS compared to age-matched control subjects. Clinical QLS was consistent with alterations in relative particle hydrodynamic radius in lenses of adolescents with DS. These correlative results suggest that noninvasive QLS can be used to evaluate molecular changes in the lenses of individuals with DS.


Assuntos
Doença de Alzheimer , Catarata/congênito , Síndrome de Down , Cristalino , Humanos , Adolescente , Síndrome de Down/complicações , Síndrome de Down/patologia , Estudos Transversais , Doença de Alzheimer/metabolismo , Cristalino/metabolismo , Peptídeos beta-Amiloides/metabolismo
2.
Ann Surg ; 273(6): 1042-1048, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33914482

RESUMO

OBJECTIVE: Our goal was to evaluate the relationship between surgeon representation on NIH study sections and success in grant funding. SUMMARY OF BACKGROUND DATA: NIH funding for surgeon-scientists is declining. Prior work has called for increased surgeon participation in the grant review process as a strategy to increase receipt of funding by surgeon-scientists. METHODS: A retrospective review of surgeon (primary department: General, Urology, Orthopedic, Ophthalmology, Otolaryngology, Neurosurgery) representation on NIH study sections and receipt of funding was performed using NIH Research Portfolio Online Reporting Tools Expenditures and Results (RePORTER) and 2019 Blue Ridge Institute for Medical Research data. NIH chartered study section panels and ad hoc reviewers for each 2019 review date were also obtained. RESULTS: In 2019, 9239 individuals reviewed in at least 1 of the 168 study sections [190 (2.1%) surgeons, 64 (0.7%) standing members, 126 (1.4%) ad-hoc]. Most surgeons on study sections were male (65%) professors (63%). Surgeons most commonly served on bioengineering, technology, and surgical sciences (29.6% surgeons), diseases and pathophysiology of the visual system (28.3%), and surgery, anesthesiology and trauma (21%). In 2019, 773 surgeons received 1235 NIH grants (>$580 M) out of a total of 55,012 awards (2.2%). Funded surgeons were predominantly male (79%), White (68%), non-Hispanic (97%), full professors (50%), and 43% had additional advanced degrees (MPH/PhD/MBA). surgery, anesthesiology and trauma, diseases and pathophysiology of the visual system, and bioengineering, technology, and surgical sciences were the most common study sections that reviewed funded grants to surgeon-scientists. Ninety-two surgeons both received grant funding and served on study section. Study sections with higher surgeon representation were more likely to fund surgeon-scientists (P < 0.001). CONCLUSIONS: Surgeon representation on NIH study sections is strongly associated with receipt of funding by surgeon-scientists. Increasing NIH study section representation by surgeons may help to preserve the surgeon-scientist phenotype.


Assuntos
Distinções e Prêmios , Pesquisa Biomédica/economia , National Institutes of Health (U.S.)/economia , Especialidades Cirúrgicas/economia , Estudos Retrospectivos , Estados Unidos
4.
Viruses ; 12(9)2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32947826

RESUMO

There is growing interest in uncovering the viral diversity present in wild animal species. The remote Antarctic region is home to a wealth of uncovered microbial diversity, some of which is associated with its megafauna, including penguin species, the dominant avian biota. Penguins interface with a number of other biota in their roles as marine mesopredators and several species overlap in their ranges and habitats. To characterize the circular single-stranded viruses related to those in the phylum Cressdnaviricota from these environmental sentinel species, cloacal swabs (n = 95) were obtained from King Penguins in South Georgia, and congeneric Adélie Penguins, Chinstrap Penguins, and Gentoo Penguins across the South Shetland Islands and Antarctic Peninsula. Using a combination of high-throughput sequencing, abutting primers-based PCR recovery of circular genomic elements, cloning, and Sanger sequencing, we detected 97 novel sequences comprising 40 ssDNA viral genomes and 57 viral-like circular molecules from 45 individual penguins. We present their detection patterns, with Chinstrap Penguins harboring the highest number of new sequences. The novel Antarctic viruses identified appear to be host-specific, while one circular molecule was shared between sympatric Chinstrap and Gentoo Penguins. We also report viral genotype sharing between three adult-chick pairs, one in each Pygoscelid species. Sequence similarity network approaches coupled with Maximum likelihood phylogenies of the clusters indicate the 40 novel viral genomes do not fall within any known viral families and likely fall within the recently established phylum Cressdnaviricota based on their replication-associated protein sequences. Similarly, 83 capsid protein sequences encoded by the viruses or viral-like circular molecules identified in this study do not cluster with any of those encoded by classified viral groups. Further research is warranted to expand knowledge of the Antarctic virome and would help elucidate the importance of viral-like molecules in vertebrate host evolution.


Assuntos
Filogenia , Spheniscidae/virologia , Vírus/classificação , Vírus/isolamento & purificação , Animais , Regiões Antárticas , Proteínas do Capsídeo/genética , Genoma Viral , Georgia , Sequenciamento de Nucleotídeos em Larga Escala , Ilhas , Vírus/genética
5.
Viruses ; 12(8)2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32781620

RESUMO

Circoviruses infect a variety of animal species and have small (~1.8-2.2 kb) circular single-stranded DNA genomes. Recently a penguin circovirus (PenCV) was identified associated with an Adélie Penguin (Pygoscelis adeliae) with feather disorder and in the cloacal swabs of three asymptomatic Adélie Penguins at Cape Crozier, Antarctica. A total of 75 cloacal swab samples obtained from adults and chicks of three species of penguin (genus: Pygoscelis) from seven Antarctic breeding colonies (South Shetland Islands and Western Antarctic Peninsula) in the 2015-2016 breeding season were screened for PenCV. We identified new variants of PenCV in one Adélie Penguin and one Chinstrap Penguin (Pygoscelis antarcticus) from Port Charcot, Booth Island, Western Antarctic Peninsula, a site home to all three species of Pygoscelid penguins. These two PenCV genomes (length of 1986 nucleotides) share > 99% genome-wide nucleotide identity with each other and share ~87% genome-wide nucleotide identity with the PenCV sequences described from Adélie Penguins at Cape Crozier ~4400 km away in East Antarctica. We did not find any evidence of recombination among PenCV sequences. This is the first report of PenCV in Chinstrap Penguins and the first detection outside of Ross Island, East Antarctica. Given the limited knowledge on Antarctic animal viral diversity, future samples from Antarctic wildlife should be screened for these and other viruses to determine the prevalence and potential impact of viral infections.


Assuntos
Circovirus/genética , Circovirus/isolamento & purificação , Genoma Viral , Spheniscidae/virologia , Animais , Regiões Antárticas , Doenças das Aves/virologia , Circovirus/classificação , Cloaca/virologia , DNA Viral/genética , Filogenia , Spheniscidae/classificação
6.
J Gerontol A Biol Sci Med Sci ; 75(9): e53-e62, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32515825

RESUMO

The absence of clinical tools to evaluate individual variation in the pace of aging represents a major impediment to understanding aging and maximizing health throughout life. The human lens is an ideal tissue for quantitative assessment of molecular aging in vivo. Long-lived proteins in lens fiber cells are expressed during fetal life, do not undergo turnover, accumulate molecular alterations throughout life, and are optically accessible in vivo. We used quasi-elastic light scattering (QLS) to measure age-dependent signals in lenses of healthy human subjects. Age-dependent QLS signal changes detected in vivo recapitulated time-dependent changes in hydrodynamic radius, protein polydispersity, and supramolecular order of human lens proteins during long-term incubation (~1 year) and in response to sustained oxidation (~2.5 months) in vitro. Our findings demonstrate that QLS analysis of human lens proteins provides a practical technique for noninvasive assessment of molecular aging in vivo.


Assuntos
Envelhecimento/fisiologia , Cristalinas/fisiologia , Difusão Dinâmica da Luz , Cristalino/fisiologia , Adolescente , Adulto , Criança , Pré-Escolar , Estudos Transversais , Cristalinas/química , Difusão Dinâmica da Luz/métodos , Eletroforese em Gel de Poliacrilamida , Feminino , Humanos , Masculino , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Oxirredução , Adulto Jovem
8.
Front Zool ; 16: 14, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31114625

RESUMO

BACKGROUND: Researchers often document wildlife surveys using images. These images contain data that can be used to understand alterative research objectives, even years after they were originally captured. We have developed a method to measure age and morphology (body size measurements and tusk size) from survey image databases and future surveys, without the availability of a known subject distance or a scale in each image. African savanna elephants (Loxodonta africana) serve as an ideal model species to develop a non-invasive, image-based morphometric methodology: as handling these animals is particularly invasive and expensive, involving anaesthesia and because of their IUCN 'vulnerable' status. We compare in situ measurements, taken during collaring events, to tusk-to-body-size ratios, measured from the images. RESULTS: We provide evidence that relative morphological measurements, musth timing, and age of male African savanna elephants can accurately be obtained from a survey image database of over 30,000 images, taken over an 18-year period. Of the 11 tusk to body size ratios calculated, we recommend the use of two in particular for future measurement in African elephants to determine size and age: 1) tusk length to tusk diameter and 2) tusk length to body height. CONCLUSIONS: We present a practical, non-invasive measure to estimate morphometrics, including both age and tusk size from photographs, which has conservation applications to the protection of elephants and is relevant to a range of other taxa.

9.
Ecol Evol ; 8(16): 8286-8296, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30250703

RESUMO

Variation in the phenology of avian taxa has long been studied to understand how a species reacts to environmental changes over both space and time. Penguins (Sphenicidae) serve as an important example of how biotic and abiotic factors influence certain stages of seabird phenology because of their large ranges and the extreme, dynamic conditions present in their Southern Ocean habitats. Here, we examined the phenology of gentoo (Pygoscelis papua) and chinstrap penguins (Pygoscelis antarctica) at 17 sites across the Scotia arc, including the first documented monitoring of phenology on the South Sandwich Islands, to determine which breeding phases are intrinsic, or rather vary across a species range and between years. We used a novel method to measure seabird breeding phenology and egg and chick survival: time-lapse cameras. Contrary to the long-standing theory that these phases are consistent between colonies, we found that latitude and season had a predominant influence on the length of the nest establishment, incubation, and guard durations. We observe a trend toward longer incubation times occurring farther south, where ambient temperatures are colder, which may indicate that exposure to cold slows embryo growth. Across species, in colonies located farther south, parents abandoned nests later when eggs were lost or chicks died and the latest record of eggs or chicks in the nest occurred earlier during the breeding period. The variation in both space and time observed in penguin phenology provides evidence that the duration of phases within the annual cycle of birds is not fundamental, or genetic, as previously understood. Additionally, the recorded phenology dates should inform field researchers on the best timing to count colonies at the peak of breeding, which is poorly understood.

10.
Sci Data ; 5: 180124, 2018 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-29944146

RESUMO

Automated time-lapse cameras can facilitate reliable and consistent monitoring of wild animal populations. In this report, data from 73,802 images taken by 15 different Penguin Watch cameras are presented, capturing the dynamics of penguin (Spheniscidae; Pygoscelis spp.) breeding colonies across the Antarctic Peninsula, South Shetland Islands and South Georgia (03/2012 to 01/2014). Citizen science provides a means by which large and otherwise intractable photographic data sets can be processed, and here we describe the methodology associated with the Zooniverse project Penguin Watch, and provide validation of the method. We present anonymised volunteer classifications for the 73,802 images, alongside the associated metadata (including date/time and temperature information). In addition to the benefits for ecological monitoring, such as easy detection of animal attendance patterns, this type of annotated time-lapse imagery can be employed as a training tool for machine learning algorithms to automate data extraction, and we encourage the use of this data set for computer vision development.


Assuntos
Spheniscidae , Imagem com Lapso de Tempo/métodos , Animais , Regiões Antárticas , Monitorização de Parâmetros Ecológicos/métodos , Dinâmica Populacional
11.
PLoS One ; 13(3): e0193532, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29561876

RESUMO

Polar seabirds adopt different over-wintering strategies to survive and build condition during the critical winter period. Penguin species either reside at the colony during the winter months or migrate long distances. Tracking studies and survey methods have revealed differences in winter migration routes among penguin species and colonies, dependent on both biotic and abiotic factors present. However, scan sampling methods are rarely used to reveal non-breeding behaviors during winter and little is known about presence at the colony site over this period. Here we show that Adélie penguins on the Yalour Islands in the Western Antarctic Peninsula (WAP) are present year-round at the colony and undergo a mid-winter peak in abundance during winter. We found a negative relationship between daylight hours and penguin abundance when either open water or compact ice conditions were present, suggesting that penguins return to the breeding colony when visibility is lowest for at-sea foraging and when either extreme low or high levels of sea ice exist offshore. In contrast, Adélie penguins breeding in East Antarctica were not observed at the colonies during winter, suggesting that Adélie penguins undergo differential winter strategies in the marginal ice zone on the WAP compared to those in East Antarctica. These results demonstrate that cameras can successfully monitor wildlife year-round in areas that are largely inaccessible during winter.


Assuntos
Migração Animal , Cruzamento , Camada de Gelo , Dinâmica Populacional , Estações do Ano , Spheniscidae/fisiologia , Animais , Mudança Climática , Ecossistema
12.
PLoS One ; 11(2): e0145676, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26840252

RESUMO

Aggregations of young animals are common in a range of endothermic and ectothermic species, yet the adaptive behavior may depend on social circumstance and local conditions. In penguins, many species form aggregations (aka. crèches) for a variety of purposes, whilst others have never been observed exhibiting this behavior. Those that do form aggregations do so for three known benefits: 1) reduced thermoregulatory requirements, 2) avoidance of unrelated-adult aggression, and 3) lower predation risk. In gentoo penguins, Pygoscelis papua, chick aggregations are known to form during the post-guard period, yet the cause of these aggregations is poorly understood. Here, for the first time, we study aggregation behavior in gentoo penguins, examining four study sites along a latitudinal gradient using time-lapse cameras to examine the adaptive benefit of aggregations to chicks. Our results support the idea that aggregations of gentoo chicks decrease an individual's energetic expenditure when wet, cold conditions are present. However, we found significant differences in aggregation behavior between the lowest latitude site, Maiviken, South Georgia, and two of the higher latitude sites on the Antarctic Peninsula, suggesting this behavior may be colony specific. We provide strong evidence that more chicks aggregate and a larger number of aggregations occur on South Georgia, while the opposite occurs at Petermann Island in Antarctica. Future studies should evaluate multiple seabird colonies within one species before generalizing behaviors based on one location, and past studies may need to be re-evaluated to determine whether chick aggregation and other behaviors are in fact exhibited species-wide.


Assuntos
Comportamento Animal , Spheniscidae/fisiologia , Adaptação Fisiológica , Envelhecimento/fisiologia , Animais , Regiões Antárticas , Regulação da Temperatura Corporal , Temperatura Baixa , Ecologia , Spheniscidae/crescimento & desenvolvimento
13.
J Mol Cell Cardiol ; 78: 54-61, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25451168

RESUMO

Mitochondrial proteins carry out diverse cellular functions including ATP synthesis, ion homeostasis, cell death signaling, and fatty acid metabolism and biogenesis. Compromised mitochondrial quality control is implicated in various human disorders including cardiac diseases. Recently it has emerged that mitochondrial protein turnover can serve as an informative cellular parameter to characterize mitochondrial quality and uncover disease mechanisms. The turnover rate of a mitochondrial protein reflects its homeostasis and dynamics under the quality control systems acting on mitochondria at a particular cell state. This review article summarizes some recent advances and outstanding challenges for measuring the turnover rates of mitochondrial proteins in health and disease. This article is part of a Special Issue entitled "Mitochondria: From Basic Mitochondrial Biology to Cardiovascular Disease".


Assuntos
Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Proteoma , Proteômica , Animais , Humanos , Proteômica/métodos
14.
Front Zool ; 11(1): 83, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25426158

RESUMO

INTRODUCTION: Urbanization can considerably impact animal ecology, evolution, and behavior. Among the new conditions that animals experience in cities is anthropogenic noise, which can limit the sound space available for animals to communicate using acoustic signals. Some urban bird species increase their song frequencies so that they can be heard above low-frequency background city noise. However, the ability to make such song modifications may be constrained by several morphological factors, including bill gape, size, and shape, thereby limiting the degree to which certain species can vocally adapt to urban settings. We examined the relationship between song characteristics and bill morphology in a species (the house finch, Haemorhous mexicanus) where both vocal performance and bill size are known to differ between city and rural animals. RESULTS: We found that bills were longer and narrower in more disturbed, urban areas. We observed an increase in minimum song frequency of urban birds, and we also found that the upper frequency limit of songs decreased in direct relation to bill morphology. CONCLUSIONS: These findings are consistent with the hypothesis that birds with longer beaks and therefore longer vocal tracts sing songs with lower maximum frequencies because longer tubes have lower-frequency resonances. Thus, for the first time, we reveal dual constraints (one biotic, one abiotic) on the song frequency range of urban animals. Urban foraging pressures may additionally interact with the acoustic environment to shape bill traits and vocal performance.

15.
J Proteome Res ; 13(2): 433-46, 2014 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-24070373

RESUMO

Mitochondria are a common energy source for organs and organisms; their diverse functions are specialized according to the unique phenotypes of their hosting environment. Perturbation of mitochondrial homeostasis accompanies significant pathological phenotypes. However, the connections between mitochondrial proteome properties and function remain to be experimentally established on a systematic level. This uncertainty impedes the contextualization and translation of proteomic data to the molecular derivations of mitochondrial diseases. We present a collection of mitochondrial features and functions from four model systems, including two cardiac mitochondrial proteomes from distinct genomes (human and mouse), two unique organ mitochondrial proteomes from identical genetic codons (mouse heart and mouse liver), as well as a relevant metazoan out-group (drosophila). The data, composed of mitochondrial protein abundance and their biochemical activities, capture the core functionalities of these mitochondria. This investigation allowed us to redefine the core mitochondrial proteome from organs and organisms, as well as the relevant contributions from genetic information and hosting milieu. Our study has identified significant enrichment of disease-associated genes and their products. Furthermore, correlational analyses suggest that mitochondrial proteome design is primarily driven by cellular environment. Taken together, these results connect proteome feature with mitochondrial function, providing a prospective resource for mitochondrial pathophysiology and developing novel therapeutic targets in medicine.


Assuntos
Proteínas Mitocondriais/metabolismo , Proteoma , Animais , Cromatografia Líquida , Drosophila melanogaster , Eletroforese em Gel de Poliacrilamida , Humanos , Camundongos , Espectrometria de Massas em Tandem
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