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1.
Cell ; 183(4): 890-904.e29, 2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-33157037

RESUMO

The Eastern Eurasian Steppe was home to historic empires of nomadic pastoralists, including the Xiongnu and the Mongols. However, little is known about the region's population history. Here, we reveal its dynamic genetic history by analyzing new genome-wide data for 214 ancient individuals spanning 6,000 years. We identify a pastoralist expansion into Mongolia ca. 3000 BCE, and by the Late Bronze Age, Mongolian populations were biogeographically structured into three distinct groups, all practicing dairy pastoralism regardless of ancestry. The Xiongnu emerged from the mixing of these populations and those from surrounding regions. By comparison, the Mongols exhibit much higher eastern Eurasian ancestry, resembling present-day Mongolic-speaking populations. Our results illuminate the complex interplay between genetic, sociopolitical, and cultural changes on the Eastern Steppe.


Assuntos
Genética Populacional , Pradaria , Arqueologia , Europa (Continente) , Feminino , Frequência do Gene/genética , Pool Gênico , Heterogeneidade Genética , Genoma Humano , Geografia , Haplótipos/genética , História Antiga , Humanos , Masculino , Mongólia , Análise de Componente Principal , Fatores de Tempo
2.
Nat Immunol ; 18(1): 96-103, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27820810

RESUMO

T lymphocytes and B lymphocytes integrate activating signals to control the size of their proliferative response. Here we report that such control was achieved by timed changes in the production rate of cell-cycle-regulating proto-oncoprotein Myc, with division cessation occurring when Myc levels fell below a critical threshold. The changing pattern of the level of Myc was not affected by cell division, which identified the regulating mechanism as a cell-intrinsic, heritable temporal controller. Overexpression of Myc in stimulated T cells and B cells did not sustain cell proliferation indefinitely, as a separate 'time-to-die' mechanism, also heritable, was programmed after lymphocyte activation and led to eventual cell loss. Together the two competing cell-intrinsic timed fates created the canonical T cell and B cell immune-response pattern of rapid growth followed by loss of most cells. Furthermore, small changes in these timed processes by regulatory signals, or by oncogenic transformation, acted in synergy to greatly enhance cell numbers over time.


Assuntos
Linfócitos B/fisiologia , Linfócitos T CD8-Positivos/fisiologia , Divisão Celular , Proliferação de Células/genética , Imunidade Celular , Proteínas Proto-Oncogênicas c-myc/metabolismo , Animais , Morte Celular/genética , Divisão Celular/genética , Células Cultivadas , Regulação da Expressão Gênica , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-myc/genética , Transdução de Sinais , Transgenes/genética
3.
Development ; 149(11)2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35451016

RESUMO

It has been established in the mouse model that during embryogenesis joint cartilage is generated from a specialized progenitor cell type, distinct from that responsible for the formation of growth plate cartilage. We recently found that mesodermal progeny of human pluripotent stem cells gave rise to two types of chondrogenic mesenchymal cells in culture: SOX9+ and GDF5+ cells. The fast-growing SOX9+ cells formed in vitro cartilage that expressed chondrocyte hypertrophy markers and readily underwent mineralization after ectopic transplantation. In contrast, the slowly growing GDF5+ cells derived from SOX9+ cells formed cartilage that tended to express low to undetectable levels of chondrocyte hypertrophy markers, but expressed PRG4, a marker of embryonic articular chondrocytes. The GDF5+-derived cartilage remained largely unmineralized in vivo. Interestingly, chondrocytes derived from the GDF5+ cells seemed to elicit these activities via non-cell-autonomous mechanisms. Genome-wide transcriptomic analyses suggested that GDF5+ cells might contain a teno/ligamento-genic potential, whereas SOX9+ cells resembled neural crest-like progeny-derived chondroprogenitors. Thus, human pluripotent stem cell-derived GDF5+ cells specified to generate permanent-like cartilage seem to emerge coincidentally with the commitment of the SOX9+ progeny to the tendon/ligament lineage.


Assuntos
Cartilagem Articular , Condrócitos , Células-Tronco Pluripotentes , Animais , Cartilagem Articular/citologia , Cartilagem Articular/metabolismo , Diferenciação Celular , Condrócitos/citologia , Condrócitos/metabolismo , Condrócitos/patologia , Condrogênese , Fator 5 de Diferenciação de Crescimento/metabolismo , Humanos , Hipertrofia , Camundongos , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo
4.
Proc Natl Acad Sci U S A ; 119(6)2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35121663

RESUMO

Predicting and disrupting transmission of human parasites from wildlife hosts or vectors remains challenging because ecological interactions can influence their epidemiological traits. Human schistosomes, parasitic flatworms that cycle between freshwater snails and humans, typify this challenge. Human exposure risk, given water contact, is driven by the production of free-living cercariae by snail populations. Conventional epidemiological models and management focus on the density of infected snails under the assumption that all snails are equally infectious. However, individual-level experiments contradict this assumption, showing increased production of schistosome cercariae with greater access to food resources. We built bioenergetics theory to predict how resource competition among snails drives the temporal dynamics of transmission potential to humans and tested these predictions with experimental epidemics and demonstrated consistency with field observations. This resource-explicit approach predicted an intense pulse of transmission potential when snail populations grow from low densities, i.e., when per capita access to resources is greatest, due to the resource-dependence of cercarial production. The experiment confirmed this prediction, identifying a strong effect of infected host size and the biomass of competitors on per capita cercarial production. A field survey of 109 waterbodies also found that per capita cercarial production decreased as competitor biomass increased. Further quantification of snail densities, sizes, cercarial production, and resources in diverse transmission sites is needed to assess the epidemiological importance of resource competition and support snail-based disruption of schistosome transmission. More broadly, this work illustrates how resource competition can sever the correspondence between infectious host density and transmission potential.


Assuntos
Biomphalaria/parasitologia , Interações Hospedeiro-Parasita/fisiologia , Schistosoma mansoni/patogenicidade , Esquistossomose mansoni/parasitologia , Caramujos/parasitologia , Animais , Humanos
5.
N Engl J Med ; 384(6): 521-532, 2021 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-33567192

RESUMO

BACKGROUND: Bilateral vestibular hypofunction is associated with chronic disequilibrium, postural instability, and unsteady gait owing to failure of vestibular reflexes that stabilize the eyes, head, and body. A vestibular implant may be effective in alleviating symptoms. METHODS: Persons who had had ototoxic (7 participants) or idiopathic (1 participant) bilateral vestibular hypofunction for 2 to 23 years underwent unilateral implantation of a prosthesis that electrically stimulates the three semicircular canal branches of the vestibular nerve. Clinical outcomes included the score on the Bruininks-Oseretsky Test of Motor Proficiency balance subtest (range, 0 to 36, with higher scores indicating better balance), time to failure on the modified Romberg test (range, 0 to 30 seconds), score on the Dynamic Gait Index (range, 0 to 24, with higher scores indicating better gait performance), time needed to complete the Timed Up and Go test, gait speed, pure-tone auditory detection thresholds, speech discrimination scores, and quality of life. We compared participants' results at baseline (before implantation) with those at 6 months (8 participants) and at 1 year (6 participants) with the device set in its usual treatment mode (varying stimulus pulse rate and amplitude to represent rotational head motion) and in a placebo mode (holding pulse rate and amplitude constant). RESULTS: The median scores at baseline and at 6 months on the Bruininks-Oseretsky test were 17.5 and 21.0, respectively (median within-participant difference, 5.5 points; 95% confidence interval [CI], 0 to 10.0); the median times on the modified Romberg test were 3.6 seconds and 8.3 seconds (difference, 5.1; 95% CI, 1.5 to 27.6); the median scores on the Dynamic Gait Index were 12.5 and 22.5 (difference, 10.5 points; 95% CI, 1.5 to 12.0); the median times on the Timed Up and Go test were 11.0 seconds and 8.7 seconds (difference, 2.3; 95% CI, -1.7 to 5.0); and the median speeds on the gait-speed test were 1.03 m per second and 1.10 m per second (difference, 0.13; 95% CI, -0.25 to 0.30). Placebo-mode testing confirmed that improvements were due to treatment-mode stimulation. Among the 6 participants who were also assessed at 1 year, the median within-participant changes from baseline to 1 year were generally consistent with results at 6 months. Implantation caused ipsilateral hearing loss, with the air-conducted pure-tone average detection threshold at 6 months increasing by 3 to 16 dB in 5 participants and by 74 to 104 dB in 3 participants. Changes in participant-reported disability and quality of life paralleled changes in posture and gait. CONCLUSIONS: Six months and 1 year after unilateral implantation of a vestibular prosthesis for bilateral vestibular hypofunction, measures of posture, gait, and quality of life were generally in the direction of improvement from baseline, but hearing was reduced in the ear with the implant in all but 1 participant. (Funded by the National Institutes of Health and others; ClinicalTrials.gov number, NCT02725463.).


Assuntos
Vestibulopatia Bilateral/cirurgia , Marcha/fisiologia , Perda Auditiva/etiologia , Neuroestimuladores Implantáveis , Equilíbrio Postural/fisiologia , Qualidade de Vida , Vestíbulo do Labirinto/cirurgia , Idoso , Vestibulopatia Bilateral/induzido quimicamente , Vestibulopatia Bilateral/complicações , Tontura/etiologia , Feminino , Transtornos Neurológicos da Marcha/etiologia , Humanos , Neuroestimuladores Implantáveis/efeitos adversos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Prospectivos , Canais Semicirculares/inervação , Nervo Vestibular/efeitos dos fármacos
6.
Psychol Sci ; 35(3): 250-262, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38289294

RESUMO

Fundamental frequency ( fo) is the most perceptually salient vocal acoustic parameter, yet little is known about how its perceptual influence varies across societies. We examined how fo affects key social perceptions and how socioecological variables modulate these effects in 2,647 adult listeners sampled from 44 locations across 22 nations. Low male fo increased men's perceptions of formidability and prestige, especially in societies with higher homicide rates and greater relational mobility in which male intrasexual competition may be more intense and rapid identification of high-status competitors may be exigent. High female fo increased women's perceptions of flirtatiousness where relational mobility was lower and threats to mating relationships may be greater. These results indicate that the influence of fo on social perceptions depends on socioecological variables, including those related to competition for status and mates.


Assuntos
Voz , Adulto , Humanos , Masculino , Feminino , Homicídio , Percepção Social , Parceiros Sexuais
7.
Neuromodulation ; 27(5): 916-922, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38971583

RESUMO

OBJECTIVES: Although studies have described inequities in spinal cord stimulation (SCS) receipt, there is a lack of information to inform system-level changes to support health care equity. This study evaluated whether Black patients exhaust more treatment options than do White patients, before receiving SCS. MATERIALS AND METHODS: This retrospective cohort study included claims data of Black and non-Latinx White patients who were active-duty service members or military retirees who received a persistent spinal pain syndrome (PSPS) diagnosis associated with back surgery within the US Military Health System, January 2017 to January 2020 (N = 8753). A generalized linear model examined predictors of SCS receipt within two years of diagnosis, including the interaction between race and number of pain-treatment types received. RESULTS: In the generalized linear model, Black patients (10.3% [8.7%, 12.0%]) were less likely to receive SCS than were White patients (13.6% [12.7%, 14.6%]) The interaction term was significant; White patients who received zero to three different types of treatments were more likely to receive SCS than were Black patients who received zero to three treatments, whereas Black and White patients who received >three treatments had similar likelihoods of receiving a SCS. CONCLUSIONS: In a health care system with intended universal access, White patients diagnosed with PSPS tried fewer treatment types before receiving SCS, whereas the number of treatment types tried was not significantly related to SCS receipt in Black patients. Overall, Black patients received SCS less often than did White patients. Findings indicate the need for structured referral pathways, provider evaluation on equity metrics, and top-down support.


Assuntos
Disparidades em Assistência à Saúde , Estimulação da Medula Espinal , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Negro ou Afro-Americano/estatística & dados numéricos , Dor Crônica/terapia , Estudos de Coortes , Serviços de Saúde Militar/estatística & dados numéricos , Militares/estatística & dados numéricos , Estudos Retrospectivos , Estimulação da Medula Espinal/métodos , Estimulação da Medula Espinal/estatística & dados numéricos , Estados Unidos/epidemiologia , Brancos/estatística & dados numéricos
8.
Am J Physiol Renal Physiol ; 325(2): F235-F247, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37348026

RESUMO

Renal nerves have been an attractive target for interventions aimed at lowering blood pressure; however, the specific roles of renal afferent (sensory) versus efferent sympathetic nerves in mediating hypertension are poorly characterized. A number of studies have suggested that a sympathoexcitatory signal conveyed by renal afferents elicits increases in blood pressure, whereas other studies identified sympathoinhibitory afferent pathways. These sympathoinhibitory pathways have been identified as protective against salt-sensitive increases in blood pressure through endothelin B (ETB) receptor activation. We hypothesized that ETB-deficient (ETB-def) rats, which are devoid of functional ETB receptors except in adrenergic tissues, lack appropriate sympathoinhibition and have lower renal afferent nerve activity following a high-salt diet compared with transgenic controls. We found that isolated renal pelvises from high salt-fed ETB-def animals lack a response to a physiological stimulus, prostaglandin E2, compared with transgenic controls but respond equally to a noxious stimulus, capsaicin. Surprisingly, we observed elevated renal afferent nerve activity in intact ETB-def rats compared with transgenic controls under both normal- and high-salt diets. ETB-def rats have been previously shown to have heightened global sympathetic tone, and we also observed higher total renal sympathetic nerve activity in ETB-def rats compared with transgenic controls under both normal- and high-salt diets. These data indicate that ETB receptors are integral mediators of the sympathoinhibitory renal afferent reflex (renorenal reflex), and, in a genetic rat model of ETB deficiency, the preponderance of sympathoexcitatory renal afferent nerve activity prevails and may contribute to hypertension.NEW & NOTEWORTHY Here, we found that endothelin B receptors are an important contributor to renal afferent nerve responsiveness to a high-salt diet. Rats lacking endothelin B receptors have increased afferent nerve activity that is not responsive to a high-salt diet.


Assuntos
Hipertensão , Rim , Ratos , Animais , Receptor de Endotelina B/genética , Receptor de Endotelina B/metabolismo , Rim/metabolismo , Pressão Sanguínea/fisiologia , Vias Aferentes/metabolismo , Cloreto de Sódio na Dieta/metabolismo , Endotelina-1/metabolismo , Receptor de Endotelina A/metabolismo
9.
Hum Genet ; 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37580609

RESUMO

Non-coding RNAs (ncRNAs) are emerging as biomarkers, molecular signatures, and therapeutic tools and targets for diseases. In this review, we focus specifically on skin diseases to highlight how two classes of ncRNAs-microRNAs and long noncoding RNAs-are being used to diagnose medical conditions of unclear etiology, improve our ability to guide treatment response, and predict disease prognosis. Furthermore, we explore how ncRNAs are being used as both as drug targets and associated therapies have unique benefits, risks, and challenges to development, but offer a distinctive promise for improving patient care and outcomes.

10.
Genome Res ; 30(1): 22-34, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31804951

RESUMO

Genome-wide association studies indicate that many disease susceptibility regions reside in non-protein-coding regions of the genome. Long noncoding RNAs (lncRNAs) are a major component of the noncoding genome, but their biological impacts are not fully understood. Here, we performed a CRISPR interference (CRISPRi) screen on 2263 epidermis-expressed lncRNAs and identified nine novel candidate lncRNAs regulating keratinocyte proliferation. We further characterized a top hit from the screen, progenitor renewal associated non-coding RNA (PRANCR), using RNA interference-mediated knockdown and phenotypic analysis in organotypic human tissue. PRANCR regulates keratinocyte proliferation, cell cycle progression, and clonogenicity. PRANCR-deficient epidermis displayed impaired stratification with reduced expression of differentiation genes that are altered in human skin diseases, including keratins 1 and 10, filaggrin, and loricrin. Transcriptome analysis showed that PRANCR controls the expression of 1136 genes, with strong enrichment for late cell cycle genes containing a CHR promoter element. In addition, PRANCR depletion led to increased levels of both total and nuclear CDKN1A (also known as p21), which is known to govern both keratinocyte proliferation and differentiation. Collectively, these data show that PRANCR is a novel lncRNA regulating epidermal homeostasis and identify other lncRNA candidates that may have roles in this process as well.


Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Epiderme/metabolismo , Regulação da Expressão Gênica , Estudo de Associação Genômica Ampla , Homeostase , Interferência de RNA , RNA Longo não Codificante/genética , Animais , Biomarcadores , Sistemas CRISPR-Cas , Ciclo Celular/genética , Linhagem Celular , Proteínas Filagrinas , Perfilação da Expressão Gênica , Técnicas de Silenciamento de Genes , Estudo de Associação Genômica Ampla/métodos , Humanos , Queratinócitos/metabolismo , Sistema de Sinalização das MAP Quinases , Camundongos , Organogênese/genética , Regiões Promotoras Genéticas , Transcriptoma
11.
Psychol Sci ; 34(11): 1271-1280, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37870245

RESUMO

In established relationships, are couples who are funny more satisfied with each other, or are satisfied couples more able to see the funny side of their partners? Much research has examined the evolutionary function of humor in relationship initiation, but not in relationship maintenance. Using a dyadic daily-diary study composed of college students from Singapore, results showed that relationship quality was positively associated with same-day humor production and perception. Importantly, and consistent with an interest-indicator perspective in which humor exchanges communicate relationship interest, relationship quality was also positively associated with next-day humor production and perception, and across both sexes. Results also indicated some support for a sexual-selection perspective in which humor exchanges predicted only same- and next-day satisfaction, but not commitment. Our findings suggest that humor can ultimately function as a strategy to monitor and maintain established relationships.


Assuntos
Cognição , Comportamento Sexual , Masculino , Feminino , Humanos , Satisfação Pessoal , Evolução Biológica , Percepção , Parceiros Sexuais
12.
Br J Dermatol ; 190(1): 10-19, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-37658835

RESUMO

Regulatory elements, particularly enhancers, play a crucial role in disease susceptibility and progression. Enhancers are DNA sequences that activate gene expression and can be affected by epigenetic modifications, interactions with transcription factors (TFs) or changes to the enhancer DNA sequence itself. Altered enhancer activity impacts gene expression and contributes to disease. In this review, we define enhancers and the experimental techniques used to identify and characterize them. We also discuss recent studies that examine how enhancers contribute to atopic dermatitis (AD) and psoriasis. Articles in the PubMed database were identified (from 1 January 2010 to 28 February 2023) that were relevant to enhancer variants, enhancer-associated TFs and enhancer histone modifications in psoriasis or AD. Most enhancers associated with these conditions regulate genes affecting epidermal homeostasis or immune function. These discoveries present potential therapeutic targets to complement existing treatment options for AD and psoriasis.


Assuntos
Dermatite Atópica , Psoríase , Humanos , Dermatite Atópica/genética , Elementos Facilitadores Genéticos/genética , Fatores de Transcrição/genética , Psoríase/genética , Epigênese Genética/genética
13.
J Org Chem ; 88(22): 15562-15568, 2023 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-37909857

RESUMO

ABBV-467 is a highly potent and selective MCL-1 inhibitor that was advanced to a phase I clinical trial for the treatment of multiple myeloma. Due to its large size and structural complexity, ABBV-467 is a challenging synthetic target. Herein, we describe the synthesis of ABBV-467 on a decagram scale, which enabled preclinical characterization. The strategy is convergent and stereoselective, featuring a hindered biaryl cross coupling, enantioselective hydrogenation, and conformationally preorganized macrocyclization by C-O bond formation as key steps.


Assuntos
Antineoplásicos , Proteína de Sequência 1 de Leucemia de Células Mieloides , Antineoplásicos/farmacologia , Hidrogenação , Proteína de Sequência 1 de Leucemia de Células Mieloides/antagonistas & inibidores
14.
Environ Sci Technol ; 57(48): 19508-19518, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37934657

RESUMO

The role of hydrogen in energy system decarbonization is being actively examined by the research and policy communities. We evaluate the potential "hydrogen economy" in global climate change mitigation scenarios using the Global Change Analysis Model (GCAM). We consider major hydrogen production methods in conjunction with delivery options to understand how hydrogen infrastructure affects its deployment. We also consider a rich set of hydrogen end-use technologies and vary their costs to understand how demand technologies affect deployment. We find that the availability of hydrogen transmission and distribution infrastructure primarily affects the hydrogen production mix, particularly the share produced centrally versus on-site, whereas assumptions about end-use technology primarily affect the scale of hydrogen deployment. In effect, hydrogen can be a source of distributed energy, enabled by on-site renewable electrolysis and, to a lesser extent, by on-site production at industrial facilities using natural gas with carbon capture and storage (CCS). While the share of hydrogen in final energy is small relative to the share of other major energy carriers in our scenarios, hydrogen enables decarbonization in difficult-to-electrify end uses, such as industrial high-temperature heat. Hydrogen deployment, and in turn its contribution to greenhouse gas mitigation, increases as the climate objective is tightened.


Assuntos
Gases de Efeito Estufa , Mudança Climática , Indústrias
15.
J Immunol ; 207(5): 1322-1332, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34341171

RESUMO

MicroRNA-21 (miR-21) inhibits IL-12 expression and impairs the Th1 response necessary for control of Leishmania infection. Recent studies have shown that Leishmania infection induces miR-21 expression in dendritic cells and macrophages, and inhibition of miR-21 restores IL-12 expression. Because miR-21 is known to be expressed due to inflammatory stimuli in a wide range of hematopoietic cells, we investigated the role of miR-21 in regulating immune responses during visceral leishmaniasis (VL) caused by Leishmania donovani infection. We found that miR-21 expression was significantly elevated in dendritic cells, macrophages, inflammatory monocytes, polymorphonuclear neutrophils, and in the spleen and liver tissues after L. donovani infection, concomitant with an increased expression of disease exacerbating IL-6 and STAT3. Bone marrow dendritic cells from miR-21 knockout (miR-21KO) mice showed increased IL-12 production and decreased production of IL-10. On L. donovani infection, miR-21KO mice exhibited significantly greater numbers of IFN-γ- and TNF-α-producing CD4+ and CD8+ T cells in their organs that was associated with increased production of Th1-associated IFN-γ, TNF-α, and NO from the splenocytes. Finally, miR-21KO mice displayed significantly more developing and mature hepatic granulomas leading to reduction in organ parasitic loads compared with wild type counterparts. Similar results were noted in L. donovani-infected wild type mice after transient miR-21 depletion. These observations indicate that miR-21 plays a critical role in pathogenesis of VL by suppressing IL-12- and Th1-associated IFN-γ and also inducing disease-promoting induction of the IL-6 and STAT-3 signaling pathway. miR-21 could therefore be used as a potential target for developing host-directed treatment for VL.


Assuntos
Células Dendríticas/imunologia , Leishmania donovani/fisiologia , Leishmaniose Visceral/imunologia , MicroRNAs/genética , Monócitos/imunologia , Neutrófilos/imunologia , Células Th1/imunologia , Animais , Células Cultivadas , Modelos Animais de Doenças , Resistência à Doença , Imunidade Celular , Interleucina-6/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator de Transcrição STAT3/metabolismo , Regulação para Cima
16.
Cell ; 135(7): 1213-23, 2008 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-19109893

RESUMO

Ultraviolet (UV) light-induced pyrimidine photodimers are repaired by the nucleotide excision repair pathway. Photolesions have biophysical parameters closely resembling undamaged DNA, impeding discovery through damage surveillance proteins. The DDB1-DDB2 complex serves in the initial detection of UV lesions in vivo. Here we present the structures of the DDB1-DDB2 complex alone and bound to DNA containing either a 6-4 pyrimidine-pyrimidone photodimer (6-4PP) lesion or an abasic site. The structure shows that the lesion is held exclusively by the WD40 domain of DDB2. A DDB2 hairpin inserts into the minor groove, extrudes the photodimer into a binding pocket, and kinks the duplex by approximately 40 degrees. The tightly localized probing of the photolesions, combined with proofreading in the photodimer pocket, enables DDB2 to detect lesions refractory to detection by other damage surveillance proteins. The structure provides insights into damage recognition in chromatin and suggests a mechanism by which the DDB1-associated CUL4 ubiquitin ligase targets proteins surrounding the site of damage.


Assuntos
Reparo do DNA , Proteínas de Ligação a DNA/metabolismo , Raios Ultravioleta , Animais , Dano ao DNA , Proteínas de Ligação a DNA/química , Humanos , Modelos Moleculares , Dímeros de Pirimidina/química , Dímeros de Pirimidina/metabolismo , Xeroderma Pigmentoso/genética , Xeroderma Pigmentoso/metabolismo , Peixe-Zebra , Proteínas de Peixe-Zebra/metabolismo
17.
Ear Hear ; 44(4): 661-669, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36763469

RESUMO

OBJECTIVES: The author's objective was to evaluate sex and race representation in temporal bone histopathology studies. DESIGN: PubMed, Embase, Cochrane, Web of Science, and Scopus were searched for studies written in English examining temporal bone histopathology specimens from U.S.-based institutions from January 1, 1947, to September 1, 2021. Two authors then performed "snowballing" by reviewing references from the initial search and included the studies that fulfilled the inclusion criteria. For each study, the following information was collected: publication details, study design, funding, institution from where temporal bone specimens were procured, number of study specimens, and donor demographical information. RESULTS: The authors found that out of 300 studies, 166 (55%) report sex while only 15 (5%) reported race information. Over the past 70 years, the ratio of studies reporting sex to those that do not has increased from 1.00 to 2.19 and the number of female temporal bone histopathology subjects relative to male has increased from 0.67 to 0.75. Over 90% of studies that do report this information feature participant racial compositions that do not reflect the diversity of the U.S. population. CONCLUSIONS: Studies of temporal bone histopathology often do not report participant sex or race. The reporting of participant sex and the inclusion of specimens from female donors have both increased over time. However, temporal bone histopathology study cohorts are not representative of the racial diversity of the U.S. population. The otolaryngology community must strive to build temporal bone histopathology libraries that are representative of the diverse U.S. population.


Assuntos
Osso Temporal , Feminino , Humanos , Masculino , Projetos de Pesquisa , Estados Unidos , Osso Temporal/patologia , Grupos Raciais , Sexo
18.
J Pers ; 91(2): 383-399, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-35567542

RESUMO

OBJECTIVE: Evolved mate preferences have taken center stage in evolutionary psychology research, yet this literature has been fairly muted on mate preferences for extrapair partners. Here, we examined the mate preferences for mistress relationships (the traits that men prioritize in a mistress and mistresses prioritize in their male partners) and compared these preferences to those of short- and long-term relationships. METHOD: In two studies (NStudy 1a  = 104, NStudy 1b  = 191), we derived dimensions of mate preferences through exploratory factor analyses. In subsequent studies (NStudy 2  = 219, NStudy 3  = 101), we employed a budget allocation paradigm, where participants designed their ideal mates for different relationship types (short-term, long-term, and mistress relationships). RESULTS: Whereas men focused on fulfilling short-term mating ideals (by prioritizing physical attractiveness) in a mistress relationship, women focused on fulfilling long-term (but also some short-term) mating ideals (prioritizing both physical attractiveness and social status) for a mistress relationship. CONCLUSION: Findings indicate that mistress relationships reflect a compromise of men's and women's (conflicting) mating ideals and contribute to an understanding of relationships that are neither completely short- nor long-term in nature.


Assuntos
Comportamento de Escolha , Parceiros Sexuais , Humanos , Masculino , Feminino , Parceiros Sexuais/psicologia , Evolução Biológica , Comportamento Sexual
19.
Aging Clin Exp Res ; 35(11): 2491-2498, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37535311

RESUMO

BACKGROUND: Recently developed absolute and body size normalized handgrip strength (HGS) cut-points could be used individually and collectively to predict mobility problems and falls. AIMS: We examined the associations of (1) each absolute and normalized weakness cut-point, (2) collective weakness categories, and (3) changes in weakness status on future falls in older Americans. METHODS: The analytic sample included 11,675 participants from the 2006-2018 waves of the Health and Retirement Study. Falls were self-reported. Men were classified as weak if their HGS was < 35.5-kg (absolute), < 0.45 kg/kg (body mass normalized), or < 1.05 kg/kg/m2 (body mass index normalized). While, women were considered weak if their HGS was < 20.0-kg, < 0.337 kg/kg, or < 0.79 kg/kg/m2. Collective weakness categorized those below 1, 2, or all 3 cut-points. The collective weakness categories were also used to observe changes in weakness status over time. RESULTS: Older Americans below each absolute and normalized cut-point had greater odds for future falls: 1.23 (95% confidence interval (CI): 1.15-1.32) for absolute weakness, 1.20 (CI 1.11-1.29) for body mass index normalized weakness, and 1.26 (CI 1.17-1.34) for body mass normalized weakness. Persons below 1, 2, or all 3 weakness cut-points had 1.17 (CI 1.07-1.27), 1.29 (CI 1.18-1.40), and 1.36 (CI 1.24-1.48) greater odds for future falls, respectively. Those in some changing weakness categories had greater odds for future falls: 1.26 (CI 1.08-1.48) for persistent and 1.31 (CI 1.11-1.55) for progressive. DISCUSSION: Collectively using these weakness cut-points may improve their predictive value. CONCLUSION: We recommend HGS be evaluated in mobility and fall risk assessments.


Assuntos
Acidentes por Quedas , Força da Mão , Masculino , Humanos , Feminino , Idoso , Aposentadoria , Autorrelato , Índice de Massa Corporal
20.
Arch Gynecol Obstet ; 307(4): 1015-1019, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36477274

RESUMO

OBJECTIVE: To evaluate whether the use of an atraumatic Allis clamp will result in less bleeding than the standard single-tooth tenaculum for cervical stabilization during intrauterine device (IUD) placement. METHODS: A single-blinded randomized controlled trial was conducted during insertions of IUDs between March 2017 and March 2018. University of Kentucky Institutional Review Board (IRB 16-1110-P3K) approval was obtained. Physicians were randomized to use either an Allis clamp or a single-tooth tenaculum for cervical stabilization. A post-procedure questionnaire was used to collect outcome measures as well as demographic and obstetric-related factors. RESULTS: Of the ninety-five participants, there was no difference in age, self-identified race/ethnicity, or the evaluated obstetric factors between the groups. Bleeding was present after clamp removal in 3 (6.3%) insertions using an Allis clamp and 26 (55.3%) insertions using a single-tooth tenaculum (RR = 0.113, CI = [0.037, 0.3481], p < 0.0001). There was no difference in IUD insertion success rates between the two clamps. There was no difference in the number of interventions needed to obtain hemostasis including indirect pressure, silver nitrate, monsel's solution, or stitch for hemostasis. Pain scores did not differ based on clamp type or age of patient, but were significantly different based on parity (p < 0.001) and IUD type (p < 0.003). CONCLUSION: Decreased incidence of bleeding from cervical stabilization device, with unchanged insertion success using the Allis clamp can be an alternative to the single tooth tenaculum in the procedure of IUD insertion. TRIAL REGISTRATION NUMBER: The trial was retrospectively registered on 1/11/22 (trial registration number NCT05187078).


Assuntos
Dispositivos Intrauterinos , Dor , Gravidez , Feminino , Humanos , Dor/etiologia , Anestésicos Locais , Dispositivos Intrauterinos/efeitos adversos , Hemorragia , Instrumentos Cirúrgicos/efeitos adversos
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