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1.
Proc Natl Acad Sci U S A ; 121(17): e2318596121, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38621142

RESUMO

While there is increasing recognition that social processes in cities like gentrification have ecological consequences, we lack nuanced understanding of the ways gentrification affects urban biodiversity. We analyzed a large camera trap dataset of mammals (>500 g) to evaluate how gentrification impacts species richness and community composition across 23 US cities. After controlling for the negative effect of impervious cover, gentrified parts of cities had the highest mammal species richness. Change in community composition was associated with gentrification in a few cities, which were mostly located along the West Coast. At the species level, roughly half (11 of 21 mammals) had higher occupancy in gentrified parts of a city, especially when impervious cover was low. Our results indicate that the impacts of gentrification extend to nonhuman animals, which provides further evidence that some aspects of nature in cities, such as wildlife, are chronically inaccessible to marginalized human populations.


Assuntos
Biodiversidade , Segregação Residencial , Animais , Humanos , Cidades , Mamíferos , Animais Selvagens , Ecossistema
2.
Glob Chang Biol ; 27(21): 5446-5459, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34405496

RESUMO

Urban biodiversity provides critical ecosystem services and is a key component to environmentally and socially sustainable cities. However, biodiversity varies greatly within and among cities, leading to human communities with changing and unequal experiences with nature. The "luxury effect," a hypothesis that predicts a positive correlation between wealth, typically measured by per capita income, and species richness may be one indication of these inequities. While the luxury effect is well studied for some taxa, it has rarely been investigated for mammals, which provide unique ecosystem services (e.g., biological pest control) and exhibit significant potential for negative human-wildlife interactions (e.g., nuisances or conflicts). We analyzed a large dataset of mammal detections across 20 North American cities to test whether the luxury effect is consistent for medium- to large-sized terrestrial mammals across diverse urban contexts. Overall, support for the luxury effect, as indicated by per capita income, was inconsistent; we found evidence of a luxury effect in approximately half of our study cities. Species richness was, however, highly and negatively correlated with urban intensity in most cities. We thus suggest that economic factors play an important role in shaping urban mammal communities for some cities and species, but that the strongest driver of urban mammal diversity is urban intensity. To better understand the complexity of urban ecosystems, ecologists and social scientists must consider the social and political factors that drive inequitable human experiences with nature in cities.


Assuntos
Ecossistema , Urbanização , Animais , Biodiversidade , Cidades , Humanos , Mamíferos
3.
J Assist Reprod Genet ; 36(1): 5-14, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30232640

RESUMO

Recent publicized events of cryogenic storage tank failures have created nationwide concern among infertility patients and patients storing embryos and gametes for future use. To assure patient confidence, quality management (QM) plans applied by in vitro fertilization (IVF) laboratories need to include a more comprehensive focus on the cryostorage of reproductive specimens. The purpose of this review is to provide best practice guidelines for the cryogenic storage of sperm, oocytes, embryos, and other reproductive tissues (e.g., testicular and ovarian tissue, cord blood cells, and stem cells) and recommend a strategy of thorough and appropriate quality and risk management procedures aimed to alleviate or minimize the consequences from catastrophic events.


Assuntos
Criopreservação/métodos , Guias de Prática Clínica como Assunto/normas , Garantia da Qualidade dos Cuidados de Saúde/normas , Técnicas de Reprodução Assistida/normas , Bancos de Tecidos/normas , Humanos
4.
Nat Ecol Evol ; 7(10): 1654-1666, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37667002

RESUMO

Human-driven environmental changes shape ecological communities from local to global scales. Within cities, landscape-scale patterns and processes and species characteristics generally drive local-scale wildlife diversity. However, cities differ in their structure, species pools, geographies and histories, calling into question the extent to which these drivers of wildlife diversity are predictive at continental scales. In partnership with the Urban Wildlife Information Network, we used occurrence data from 725 sites located across 20 North American cities and a multi-city, multi-species occupancy modelling approach to evaluate the effects of ecoregional characteristics and mammal species traits on the urbanization-diversity relationship. Among 37 native terrestrial mammal species, regional environmental characteristics and species traits influenced within-city effects of urbanization on species occupancy and community composition. Species occupancy and diversity were most negatively related to urbanization in the warmer, less vegetated cities. Additionally, larger-bodied species were most negatively impacted by urbanization across North America. Our results suggest that shifting climate conditions could worsen the effects of urbanization on native wildlife communities, such that conservation strategies should seek to mitigate the combined effects of a warming and urbanizing world.

5.
PLoS One ; 17(3): e0265666, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35324968

RESUMO

As anthropogenic changes continue to ecologically stress wildlife, obtaining measures of gene flow and genetic diversity are crucial for evaluating population trends and considering management and conservation strategies for small, imperiled populations. In our study, we conducted a molecular assessment to expand on previous work to elucidate patterns of diversity and connectivity in the remaining disjunct Eastern Massasauga Rattlesnake (Sistrurus catenatus) hibernacula in Illinois. We assayed genetic data for 327 samples collected during 1999-2015 from the Carlyle Lake study area across 21 microsatellite loci. We found hibernacula formed distinct genetic clusters corresponding to the three main study areas (Dam Recreation Areas, Eldon Hazlet State Park, and South Shore State Park). Genetic structuring and low estimates of dispersal indicated that connectivity among these study areas is limited and each is demographically independent. Hibernacula exhibited moderate levels of heterozygosity (0.60-0.73), but estimates of effective population size (5.2-41.0) were low and track census sizes generated via long-term mark-recapture data. Hibernacula at Carlyle Lake, which represent the only Eastern Massasauga remaining in Illinois, are vulnerable to future loss of genetic diversity through lack of gene flow as well as demographic and environmental stochastic processes. Our work highlights the need to include population-level genetic data in recovery planning and suggests that recovery efforts should focus on managing the three major study areas as separate conservation units in order to preserve and maintain long-term adaptive potential of these populations. Specific management goals should include improving connectivity among hibernacula, maintaining existing wet grassland habitat, and minimizing anthropogenic sources of mortality caused by habitat management (e.g., mowing, prescribed fire) and recreational activities. Our molecular study provides additional details about demographic parameters and connectivity at Carlyle Lake that can be used to guide recovery of Eastern Massasauga in Illinois and throughout its range.


Assuntos
Crotalinae , Fluxo Gênico , Animais , Crotalus , Variação Genética , Genética Populacional , Pradaria , Illinois
6.
PLoS One ; 16(12): e0260344, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34882713

RESUMO

Ecological restoration can promote biodiversity conservation in anthropogenically fragmented habitats, but effectiveness of these management efforts need to be statistically validated to determine 'success.' One such approach is to gauge the extent of recolonization as a measure of landscape permeability and, in turn, population connectivity. In this context, we estimated dispersal and population connectivity in prairie vole (Microtus ochrogaster; N = 231) and meadow vole (M. pennsylvanicus; N = 83) within five tall-grass prairie restoration sites embedded within the agricultural matrix of midwestern North America. We predicted that vole dispersal would be constrained by the extent of agricultural land surrounding restored habitat patches, spatially isolating vole populations and resulting in significant genetic structure. We first employed genetic assignment tests based on 15 microsatellite DNA loci to validate field-derived species-designations, then tested reclassified samples with multivariate and Bayesian clustering to assay for spatial and temporal genetic structure. Population connectivity was further evaluated by calculating pairwise FST, then potential demographic effects explored by computing migration rates, effective population size (Ne), and average relatedness (r). Genetic species assignments reclassified 25% of initial field identifications (N = 11 M. ochrogaster; N = 67 M. pennsylvanicus). In M. ochrogaster population connectivity was high across the study area, reflected in little to no spatial or temporal genetic structure. In M. pennsylvanicus genetic structure was detected, but relatedness estimates identified it as kin-clustering instead, underscoring social behavior among populations rather than spatial isolation as the cause. Estimates of Ne and r were stable across years, reflecting high dispersal and demographic resilience. Combined, these metrics suggest the agricultural matrix is highly permeable for voles and does not impede dispersal. High connectivity observed confirms that the restored landscape is productive and permeable for specific management targets such as voles and also demonstrates population genetic assays as a tool to statistically evaluate effectiveness of conservation initiatives.


Assuntos
Arvicolinae/classificação , Arvicolinae/fisiologia , Repetições de Microssatélites , Animais , Arvicolinae/genética , Teorema de Bayes , Recuperação e Remediação Ambiental , Feminino , Fluxo Gênico , Variação Genética , Genética Populacional , Pradaria , América do Norte , Densidade Demográfica , Dinâmica Populacional
7.
Eur J Med Genet ; 63(2): 103731, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31362121

RESUMO

The clinical application of a PGT-A program implementing single euploid embryo transfer is evaluated over a 6.5 year period, beginning with its early validation phases. Euploidy embryo status is inversely correlated to oocyte source age and positively correlated to blastocyst quality grades. However, once a single euploid embryo is transferred, high levels of implantation and live birth success are attained independent of patient age and embryo quality, with only AA blastocysts exhibiting improved implantation. Factors influencing successful outcomes are discussed, including the management of mosaic NGS profiles. Overall, distinct advantages to a dedicated PGT-A/single euploid embryo transfer program are clearly evident in per cycle start comparisons to control cycles and national average statistics by age groups.


Assuntos
Aneuploidia , Implantação do Embrião/genética , Fertilização in vitro , Testes Genéticos/métodos , Diagnóstico Pré-Implantação/métodos , Adulto , Blastocisto/citologia , Blastocisto/fisiologia , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Nascido Vivo , Mosaicismo , Oócitos/citologia , Oócitos/fisiologia , Gravidez
8.
PLoS One ; 15(4): e0230735, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32339176

RESUMO

Despite its imperative, biodiversity conservation is chronically underfunded, a deficiency that often forces management agencies to prioritize. Single-species recovery thus becomes a focus (often with socio-political implications), whereas a more economical approach would be the transition to multi-targeted management (= MTM). This challenge is best represented in Midwestern North America where biodiversity has been impacted by 300+ years of chronic anthropogenic disturbance such that native tall-grass prairie is now supplanted by an agroecosystem. Here, we develop an MTM with a population genetic metric to collaboratively manage three Illinois upland gamebirds: common pheasant (Phasianus colchicus; pheasant), northern bobwhite quail (Colinus virginianus; quail), and threatened-endangered (T&E) greater prairie chicken (Tympanuchus cupido pinnatus; prairie chicken). We first genotyped our study pheasant at 19 microsatellite DNA loci and identified three captive breeding stocks (N = 143; IL Department of Natural Resources) as being significantly bottlenecked, with relatedness >1st-cousin (µR = 0.158). 'Wild' (non-stocked) pheasant [N = 543; 14 Pheasant-Habitat-Areas (PHAs)] were also bottlenecked, significantly interrelated (µR = 0.150) and differentiated (µFST = 0.047), yet distinct from propagation stock. PHAs that encompassed significantly with larger areas also reflected greater effective population sizes (µNE = 43; P<0.007). We juxtaposed these data against previously published results for prairie chicken and quail, and found population genetic structure driven by drift, habitat/climate impacts, and gender-biased selection via hunter-harvest. Each species (hunter-harvested or T&E) is independently managed, yet their composite population genetic baseline provides the quantitative criteria needed for an upland game bird MTM. Its implementation would require agricultural plots to be rehabilitated/reclaimed using a land-sharing/sparing portfolio that differs markedly from the Conservation Reserve Program (CRP), where sequestered land decreases as agricultural prices escalate. Cost-savings for an MTM would accrue by synchronizing single-species management with a dwindling hunter-harvest program, and by eliminating propagation/stocking programs. This would sustain not only native grasslands and their resident species, but also accelerate conservation at the wildlife-agroecosystem interface.


Assuntos
Aves , Conservação dos Recursos Naturais , Ecossistema , Agricultura , Animais , Aves/genética , Variação Genética , Técnicas de Genotipagem , América do Norte
10.
Mol Cell Biol ; 5(7): 1784-6, 1985 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2991750

RESUMO

A fragment of the human gene for c-erb-B was used to map homologous sequences in mice. Analysis of somatic cell hybrids and recombinant inbred and congenic mouse strains indicated that this gene, designated Erbb, is closely linked to the gene for alpha-globin on mouse chromosome 11. Several genes controlling hematopoietic differentiation map to mouse chromosome 11.


Assuntos
Globinas/genética , Oncogenes , Animais , Mapeamento Cromossômico , Receptores ErbB , Ligação Genética , Hematopoese , Células Híbridas , Camundongos , Receptores de Superfície Celular/genética
11.
J Invest Dermatol ; 93(5): 589-94, 1989 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2507645

RESUMO

Using a human tyrosinase cDNA probe, we have isolated mouse tyrosinase genomic clones and used them to map the mouse tyrosinase locus and to analyze the promoter sequence of the tyrosinase gene. Southern blot analyses of DNA from somatic cell hybrids, interspecies backcross mice, and albino deletion mice have revealed that the locus for mouse tyrosinase resides at or near the albino locus on mouse chromosome 7. There were three TATA-elements, but only one CAT-element, and the CAT-element appeared to be paired with the third TATA-element, located at the position farthest upstream. Mouse tyrosinase mRNA is approximately 2.4 Kb in size. The amount of tyrosinase mRNA reflects the levels of tyrosinase activity in normal melanocytes and Cloudman S-91 melanoma cell line.


Assuntos
Catecol Oxidase/genética , Monofenol Mono-Oxigenase/genética , Albinismo/genética , Animais , Sequência de Bases , Northern Blotting , Southern Blotting , Mapeamento Cromossômico , Sondas de DNA , Regulação Enzimológica da Expressão Gênica , Genes , Melanócitos/fisiologia , Melanoma Experimental/genética , Camundongos , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Mapeamento por Restrição
13.
Physiol Behav ; 17(6): 1019-21, 1976 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14677599

RESUMO

Sprague-Dawley rats were exposed to the stress of restraint, heat and bright lights three times daily from Days 14 to 22 of gestation. Because prepartal stress did not markedly disturb the mother's retrieving and crouching behavior, disturbances in postpartal nursing behavior do not seem to account for the abnormal sexual behavior of male offspring as adults. The most significant finding was that litter weights were reduced, not only at birth, but for 3 weeks thereafter, suggesting that prepartal stress not only altered the pups in utero but also affected postpartal milk synthesis. The possibility emerges that prepartal stress may alter adult sexual behavior in males by modifications in fetal and/or maternal pituitary glands.


Assuntos
Efeitos Tardios da Exposição Pré-Natal , Comportamento Sexual Animal/fisiologia , Estresse Psicológico/fisiopatologia , Animais , Animais Recém-Nascidos , Animais Lactentes , Peso Corporal/fisiologia , Feminino , Lactação/fisiologia , Masculino , Comportamento Materno/fisiologia , Gravidez , Ratos , Restrição Física , Caracteres Sexuais
14.
Physiol Behav ; 19(1): 167-9, 1977 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11803682

RESUMO

Sprague-Dawley females were exposed to the stress of heat, restraint and bright lights during the third trimester of gestation. Virtually all male offspring tested for masculine sexual behavior as adults ejaculated and copulated with lure females. Also prenatally-stressed males exhibited two to three times as many lordotic responses as did males from nonstressed mothers. Because animals were crossfostered, an in utero action of prenatal stress is supported. Anterior hypothalamic (AHA) lesions significantly reduced the number of lordotic responses observed in prenatally-stressed male rats compared to those observed in prenatally-stressed males bearing sham lesions of the AHA. The possibility is presented that prenatal stress may influence the developing male brain.


Assuntos
Nível de Alerta/fisiologia , Hipotálamo Anterior/fisiologia , Efeitos Tardios da Exposição Pré-Natal , Comportamento Sexual Animal/fisiologia , Animais , Feminino , Masculino , Gravidez , Ratos , Diferenciação Sexual/fisiologia , Maturidade Sexual/fisiologia
19.
J Virol ; 80(17): 8729-38, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16912320

RESUMO

Human immunodeficiency virus type 1 (HIV-1) clade C causes >50% of all HIV infections worldwide, and an estimated 90% of all transmissions occur mucosally with R5 strains. A pathogenic R5 simian-human immunodeficiency virus (SHIV) encoding HIV clade C env is highly desirable to evaluate candidate AIDS vaccines in nonhuman primates. To this end, we generated SHIV-1157i, a molecular clone from a Zambian infant isolate that carries HIV clade C env. SHIV-1157i was adapted by serial passage in five monkeys, three of which developed peripheral CD4(+) T-cell depletion. After the first inoculated monkey developed AIDS at week 137 postinoculation, transfer of its infected blood to a naïve animal induced memory T-cell depletion and thrombocytopenia within 3 months in the recipient. In parallel, genomic DNA from the blood donor was amplified to generate the late proviral clone SHIV-1157ipd3. To increase the replicative capacity of SHIV-1157ipd3, an extra NF-kappaB binding site was engineered into its 3' long terminal repeat, giving rise to SHIV-1157ipd3N4. This virus was exclusively R5 tropic and replicated more potently in rhesus peripheral blood mononuclear cells than SHIV-1157ipd3 in the presence of tumor necrosis factor alpha. Rhesus macaques of Indian and Chinese origin were next inoculated intrarectally with SHIV-1157ipd3N4; this virus replicated vigorously in both sets of monkeys. We conclude that SHIV-1157ipd3N4 is a highly replication-competent, mucosally transmissible R5 SHIV that represents a valuable tool to test candidate AIDS vaccines targeting HIV-1 clade C Env.


Assuntos
Infecções por HIV/transmissão , HIV-1/classificação , HIV-1/patogenicidade , Receptores de Citocinas/metabolismo , Síndrome de Imunodeficiência Adquirida dos Símios/transmissão , Vírus da Imunodeficiência Símia/patogenicidade , Administração Retal , Sequência de Aminoácidos , Animais , Quimera , Clonagem Molecular , Produtos do Gene env/genética , Infecções por HIV/virologia , HIV-1/genética , Humanos , Lactente , Macaca mulatta , Dados de Sequência Molecular , Receptores CXCR5 , Receptores de Quimiocinas , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/genética , Replicação Viral
20.
Biochem Genet ; 22(9-10): 913-22, 1984 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6440531

RESUMO

A unique electrophoretic form of carbonic anhydrase is characteristic of some laboratory-maintained mice of the wild mouse species Mus spretus. This isozyme has been characterized by cellulose acetate electrophoresis and by isoelectric focusing. It is proposed that this isozyme be called CAR-2C and that its encoding allele be designated Car-2c. Fertile hybrids of Mus spretus and C57BL/6J (Car-2a) show both CAR-2A and CAR-2C bands of approximately equal intensity. The CAR-2C isozyme is readily identified by electrophoresis on 75-mm cellulose acetate strips because it migrates significantly faster than the isozymes of inbred mice, the CAR-2A and CAR-2B that do not separate from one another under standard conditions. Isoelectric focusing cleanly resolves all three of these CAR-2 forms. Mus hortulanus, although closely related to Mus spretus in other biochemical-genetic characteristics, has a CAR-2-homologous isozyme that is distinctly different from the CAR-2C of Mus spretus and from the isozymes of the common inbred strains.


Assuntos
Anidrases Carbônicas/genética , Muridae/genética , Alelos , Animais , Anidrases Carbônicas/sangue , Hibridização Genética , Ponto Isoelétrico
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