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1.
J Nutr ; 154(1): 87-94, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37940004

RESUMO

BACKGROUND: Research suggests omega-3 polyunsaturated fatty acids (PUFAs) exert favorable effects on several biological processes involved in the development and progression of atherosclerotic cardiovascular disease (ASCVD). However, studies examining the relationship between omega-3 PUFAs and peripheral artery disease (PAD) are scarce. OBJECTIVES: We evaluated the associations between omega-3 PUFAs and incident PAD in a meta-analysis of the Multi-Ethnic Study of Atherosclerosis (MESA) and Atherosclerosis Risk in Communities (ARIC) study cohorts. METHODS: Omega-3 PUFAs eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were measured at baseline for all MESA (n = 6495) and Minnesota ARIC participants (n = 3612). Incident clinical PAD events (MESA n = 106; ARIC n = 149) identified primarily through ICD discharge codes were assessed through follow-up of each cohort. Associations between omega-3 PUFAs (EPA, DHA, and EPA+DHA) and incident PAD were modeled in MESA and ARIC as quartiles and continuously using Cox proportional hazards regression, respectively. A fixed-effects meta-analysis was conducted to evaluate associations in the 2 cohorts combined. RESULTS: In the fully adjusted model, in 10,107 participants, no significant associations were observed between EPA, DHA, or EPA+DHA, and incident PAD modeled as quartiles or continuously for either MESA or ARIC cohorts separately or in the meta-analysis after a follow-up of approximately 15 y. CONCLUSION: This study is consistent with previous literature indicating that the beneficial effects of omega-3 PUFAs on the markers of ASCVD may not translate to a clinically meaningful decrease in PAD risk.


Assuntos
Aterosclerose , Ácidos Graxos Ômega-3 , Doença Arterial Periférica , Humanos , Ácido Eicosapentaenoico/farmacologia , Ácidos Docosa-Hexaenoicos/farmacologia , Aterosclerose/prevenção & controle
2.
Nutr Metab Cardiovasc Dis ; 34(6): 1399-1406, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38402001

RESUMO

BACKGROUND AND AIM: Left ventricular hypertrophy (LVH) has been shown to be associated with the occurrence of atrial fibrillation (AF). However, the predictive value of the LVH phenotype for incident AF remains uncertain. This study aimed to investigate the predictive value of LVH phenotype for incident AF. METHODS AND RESULTS: This study utilized the Multi-Ethnic Study of Atherosclerosis (MESA) data. LVH was defined by cardiac magnetic resonance measured LV mass index. Isolated LVH was determined as LVH without elevated cardiac biomarker and malignant LVH was determined as LVH with at least 1 elevated biomarker. Receiver-operating characteristic (ROC) analysis was performed to calculate areas under the curves (AUC) for predicting AF. A total of 4983 community-dwelling participants were included, with a mean age of 61.5 years. 279 (5.6 %) had isolated LVH, and 222 (4.5 %) had malignant LVH. During a median follow-up of 8.5 years, 272 incident AF was observed. Compared to participants without LVH and elevated cardiac biomarkers, those with isolated LVH (HR, 1.82; 95 % CI, 1.03-3.20) and malignant LVH (HR, 4.13; 95 % CI, 2.77-6.16) had a higher risk of incident AF. Malignant LVH carried a 1.5-fold increased risk of AF compared to isolated LVH (HR: 2.48, 95 % CI: 1.30-4.73). Including the LVH phenotype in the CHARGE-AF model improved model discrimination (AUC increase: 0.03, p < 0.001). CONCLUSIONS: The risks of AF incidence varied across LVH phenotypes. Malignant LVH carried the highest risk among LVH phenotypes. LVH phenotype provides incremental predictive value over the variables included in the CHARGE-AF model.


Assuntos
Fibrilação Atrial , Hipertrofia Ventricular Esquerda , Fenótipo , Valor Preditivo dos Testes , Humanos , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/etnologia , Fibrilação Atrial/fisiopatologia , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/epidemiologia , Hipertrofia Ventricular Esquerda/etnologia , Hipertrofia Ventricular Esquerda/fisiopatologia , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Incidência , Medição de Risco , Fatores de Risco , Estados Unidos/epidemiologia , Idoso de 80 Anos ou mais , Prognóstico , Fatores de Tempo , Função Ventricular Esquerda , Biomarcadores/sangue , Estudos Prospectivos
3.
Biol Pharm Bull ; 47(2): 417-426, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38296488

RESUMO

Small molecule drugs containing morpholine-based moieties have become crucial candidates in the tumor targeted therapy strategies, but the specific molecular mechanisms of these drugs causing tumor cell death require further investigation. The morpholine derivative N-(4-morpholinomethylene)ethanesulfonamide (MESA) was used to stimulate prostate and ovarian cancer cells and we focused on the ferroptosis effects, including the target molecule and signal pathways mediated by MESA. The results showed that MESA could induce ferroptosis to cause the proliferation inhibition and apoptosis effects of tumor cells according to the identification of ferroptosis inhibitor fer-1 and other cell death inhibitors. Further MESA could significantly increase the intracellular malondialdehyde (MDA), reactive oxygen species (ROS) and Fe2+ levels in tumor cells and mediate the dynamic changes of ferroptosis-relative molecules GPX4, nuclear factor erythroid2-related factor 2 (NRF2), ACSL4, SLC7A11 and P62-Kelch-like ECH-associated protein 1 (KEAP1)-NRF2-antioxidant response element (ARE) signal pathways. Further, NRF2 overexpression could reduce the tumor cell death and ROS levels exposure to MESA. Most importantly, it was confirmed that MESA could bind to NRF2 protein through molecular docking and thermal stability assays and NRF2 was a target molecule of MESA for inducing ferroptosis effects in tumor cells. Collectively, our findings indicated the ferroptosis effects of the morpholine derivative MESA in prostate and ovarian cancer cells and its function mechanism including targeted molecule and signal pathways, which would be helpful for developing MESA as a prospective small molecule drug for cancer therapy based on cell ferroptosis.


Assuntos
Ferroptose , Neoplasias Ovarianas , Masculino , Feminino , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch , Simulação de Acoplamento Molecular , Fator 2 Relacionado a NF-E2 , Estudos Prospectivos , Espécies Reativas de Oxigênio , Morfolinas/farmacologia , Neoplasias Ovarianas/tratamento farmacológico
4.
Proc Natl Acad Sci U S A ; 118(51)2021 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-34903653

RESUMO

We investigated historical redlining, a government-sanctioned discriminatory policy, in relation to cardiovascular health (CVH) and whether associations were modified by present-day neighborhood physical and social environments. Data included 4,779 participants (mean age 62 y; SD = 10) from the baseline sample of the Multi-Ethnic Study of Atherosclerosis (MESA; 2000 to 2002). Ideal CVH was a summary measure of ideal levels of seven CVH risk factors based on established criteria (blood pressure, fasting glucose, cholesterol, body mass index, diet, physical activity, and smoking). We assigned MESA participants' neighborhoods to one of four grades (A: best, B: still desirable, C: declining, and D: hazardous) using the 1930s federal Home Owners' Loan Corporation (HOLC) maps, which guided decisions regarding mortgage financing. Two-level hierarchical linear and logistic models, with a random intercept to account for participants nested within neighborhoods (i.e., census tracts) were used to assess associations within racial/ethnic subgroups (non-Hispanic White, non-Hispanic Black, Hispanic, and non-Hispanic Chinese). We found that Black adults who lived in historically redlined areas had a 0.82 (95% CI -1.54, -0.10) lower CVH score compared to those residing in grade A (best) neighborhoods, in a given neighborhood and adjusting for confounders. We also found that as the current neighborhood social environment improved the association between HOLC score and ideal CVH weakened (P < 0.10). There were no associations between HOLC grade and CVH measures or effect modification by current neighborhood conditions for any other racial/ethnic group. Results suggest that historical redlining has an enduring impact on cardiovascular risk among Black adults in the United States.


Assuntos
Aterosclerose/epidemiologia , Racismo , Características de Residência , Idoso , Idoso de 80 Anos ou mais , Aterosclerose/etnologia , Feminino , Disparidades nos Níveis de Saúde , Fatores de Risco de Doenças Cardíacas , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Grupos Raciais , Meio Social , Estados Unidos/epidemiologia
5.
Conserv Biol ; 37(3): e14052, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36661057

RESUMO

The Common Agricultural Policy (CAP) is the European Union's main instrument for agricultural planning, with a new reform approved for 2023-2027. The CAP intends to align with the European Green Deal (EGD), a set of policy initiatives underpinning sustainable development and climate neutrality in the European Union (EU), but several flaws cast doubts about the compatibility of the objectives of these 2 policies. We reviewed recent literature on the potential of CAP environmental objectives for integration with the EGD: protection of biodiversity, climate change mitigation and adaptation, and sustainable management of natural resources. The CAP lacks appropriate planning measures, furthering instead risks to biodiversity and ecosystem services driven by landscape and biotic homogenization. Funding allocation mechanisms are not tailored to mitigate agricultural emissions, decreasing the efficiency of climate mitigation actions. The legislation subsidies farmers making extensive use of synthetic inputs without adequately supporting organic production, hindering the transition toward sustainable practices. We recommend proper control mechanisms be introduced in CAP Strategic Plans from each member state to ensure the EU is set on a sustainable production and consumption path. These include proportional assignment of funds to each CAP objective, quantitative targets to set goals and evidence-based interventions, and relevant indicators to facilitate effective monitoring of environmental performance. Both the CAP and the EGD should maintain ambitious environmental commitments in the face of crisis to avoid further degradation of the natural resources on which production systems stand.


Oportunidades y retos para la reforma a la Política Agrícola Común que respalden el Pacto Verde Europeo Resumen La Política Agrícola Común (PAC) es el principal instrumento de planificación agraria de la Unión Europea, con una nueva reforma aprobada para 2023-2027. La PAC pretende alinearse con el Pacto Verde Europeo (PVE), un conjunto de iniciativas políticas que apuntan al desarrollo sostenible y la neutralidad climática en la UE, aunque varias fallas han arrojado dudas sobre la compatibilidad de los objetivos de estas dos políticas. Revisamos la bibliografía reciente sobre el potencial de integración de los objetivos medioambientales de la PAC con el PVE en tres categorías: protección de la biodiversidad; mitigación del cambio climático y adaptación al mismo y, gestión sostenible de los recursos naturales. Encontramos que la PAC carece de medidas de planificación adecuadas, lo que agrava los riesgos para la biodiversidad y los servicios ambientales derivados de la homogeneización biótica y paisajística. Los mecanismos de asignación de fondos no están adaptados para mitigar las emisiones agrícolas, lo que disminuye la eficiencia de las acciones de mitigación del cambio climático. La legislación subsidia a los agricultores que hacen un uso extensivo de insumos sintéticos sin apoyar adecuadamente la producción ecológica, obstaculizando la transición hacia prácticas sostenibles. Recomendamos que se introduzcan mecanismos de control adecuados en los Planes Estratégicos de la PAC de cada Estado miembro para garantizar que la UE se encamina hacia una producción y un consumo sostenibles. Estos mecanismos incluyen la asignación proporcional de fondos a cada objetivo de la PAC, objetivos cuantitativos para fijar metas e intervenciones basadas en pruebas, e indicadores pertinentes para facilitar un seguimiento eficaz de los resultados medioambientales. Tanto la PAC como el PVE deben mantener compromisos medioambientales ambiciosos frente a la crisis para evitar una mayor degradación de los recursos naturales sobre los que se asientan los sistemas de producción.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Agricultura , Biodiversidade , Políticas
6.
Sensors (Basel) ; 23(22)2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-38005607

RESUMO

This paper presents the complete design, fabrication, and characterization of a shallow-mesa photodiode for short-wave infra-red (SWIR) sensing. We characterized and demonstrated photodiodes collecting 1.55 µm photons with a pixel pitch as small as 3 µm. For a 5 µm pixel pitch photodiode, we measured the external quantum efficiency reaching as high as 54%. With substrate removal and an ideal anti-reflective coating, we estimated the internal quantum efficiency as achieving 77% at 1.55 µm. The best measured dark current density reached 5 nA/cm2 at -0.1 V and at 23 °C. The main contributors responsible for this dark current were investigated through the study of its evolution with temperature. We also highlight the importance of passivation with a perimetric contribution analysis and the correlation between MIS capacitance characterization and dark current performance.

7.
Am J Respir Crit Care Med ; 203(9): 1173-1182, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33285084

RESUMO

Rationale: Symptoms and morbidities associated with obstructive sleep apnea (OSA) vary across individuals and are not predicted by the apnea-hypopnea index (AHI). Respiratory event duration is a heritable trait associated with mortality that may further characterize OSA.Objectives: We evaluated how hypopnea and apnea durations in non-REM (NREM) sleep vary across demographic groups and quantified their associations with physiological traits (loop gain, arousal threshold, circulatory delay, and pharyngeal collapsibility).Methods: Data were analyzed from 1,546 participants from the Multi-Ethnic Study of Atherosclerosis with an AHI ≥5. Physiological traits were derived using a validated model fit to the polysomnographic airflow signal. Multiple linear regression models were used to evaluate associations of event duration with demographic and physiological factors.Measurements and Main Results: Participants had a mean age ± SD of 68.9 ± 9.2 years, mean NREM hypopnea duration of 21.73 ± 5.60, and mean NREM apnea duration of 23.87 ± 7.44 seconds. In adjusted analyses, shorter events were associated with younger age, female sex, higher body mass index (P < 0.01, all), and Black race (P < 0.05). Longer events were associated with Asian race (P < 0.01). Shorter event durations were associated with lower circulatory delay (2.53 ± 0.13 s, P < 0.01), lower arousal threshold (1.39 ± 0.15 s, P < 0.01), reduced collapsibility (-0.71 ± 0.16 s, P < 0.01), and higher loop gain (-0.27 ± 0.11 s, P < 0.05) per SD change. Adjustment for physiological traits attenuated age, sex, and obesity associations and eliminated racial differences in event duration.Conclusions: Average event duration varies across population groups and provides information on ventilatory features and airway collapsibility not captured by the AHI.


Assuntos
Etnicidade/estatística & dados numéricos , Apneia Obstrutiva do Sono/epidemiologia , Apneia Obstrutiva do Sono/fisiopatologia , Sono REM/fisiologia , População Branca/estatística & dados numéricos , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Nível de Alerta , Índice de Massa Corporal , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Faringe/fisiopatologia , Polissonografia , Taxa Respiratória , Fatores de Risco , Fatores Sexuais , Apneia Obstrutiva do Sono/diagnóstico , Fatores de Tempo
8.
BMC Genomics ; 22(1): 790, 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34732130

RESUMO

BACKGROUND: The complexity of physical activity (PA) and DNA methylation interaction in the development of cardiovascular disease (CVD) is rarely simultaneously investigated in one study. We examined the role of DNA methylation on the association between PA and CVD. RESULTS: The Multi-Ethnic Study of Atherosclerosis (MESA) cohort Exam 5 data with 1065 participants free of CVD were used for final analysis. The quartile categorical total PA variable was created by activity intensity (METs/week). During a median follow-up of 4.0 years, 69 participants developed CVD. Illumina HumanMethylation450 BeadChip was used to provide genome-wide DNA methylation profiles in purified human monocytes (CD14+). We identified 23 candidate DNA methylation loci to be associated with both PA and CVD. We used the structural equation modeling (SEM) approach to test the complex relationships among multiple variables and the roles of mediators. Three of the 23 identified loci (corresponding to genes VPS13D, PIK3CD and VPS45) remained as significant mediators in the final SEM model along with other covariates. Bridged by the three genes, the 2nd PA quartile (ß = - 0.959; 95%CI: - 1.554 to - 0.449) and the 3rd PA quartile (ß = - 0.944; 95%CI: - 1.628 to - 0.413) showed the greatest inverse associations with CVD development, while the 4th PA quartile had a relatively weaker inverse association (ß = - 0.355; 95%CI: - 0.713 to - 0.124). CONCLUSIONS: The current study is among the first to simultaneously examine the relationships among PA, DNA methylation, and CVD in a large cohort with long-term exposure. We identified three DNA methylation loci bridged the association between PA and CVD. The function of the identified genes warrants further investigation in the pathogenesis of CVD.


Assuntos
Aterosclerose , Doenças Cardiovasculares , Aterosclerose/genética , Doenças Cardiovasculares/genética , Metilação de DNA , Etnicidade , Exercício Físico , Humanos , Fatores de Risco
9.
Am J Bot ; 108(9): 1808-1815, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34590302

RESUMO

PREMISE: Plant domestication can be detected when transport, use, and manipulation of propagules impact reproductive functionality, especially in species with self-incompatible breeding systems. METHODS: Evidence for human-caused founder effect in the Four Corners potato (Solanum jamesii Torr.) was examined by conducting 526 controlled matings between archaeological and non-archaeological populations from field-collected tubers grown in a greenhouse. Specimens from 24 major herbaria and collection records from >160 populations were examined to determine which produced fruits. RESULTS: Archaeological populations did not produce any fruits when self-crossed or outcrossed between individuals from the same source. A weak ability to self- or outcross within populations was observed in non-archaeological populations. Outcrossing between archaeological and non-archaeological populations, however, produced fully formed, seed-containing fruits, especially with a non-archaeological pollen source. Fruit formation was observed in 51 of 162 occurrences, with minimal evidence of constraint by monsoonal drought, lack of pollinators, or spatial separation of suitable partners. Some archaeological populations (especially those along ancient trade routes) had records of fruit production (Chaco Canyon), while others (those in northern Arizona, western Colorado, and southern Utah) did not. CONCLUSIONS: The present study suggests that archaeological populations could have different origins at different times-some descending directly from large gene pools to the south and others derived from gardens already established around occupations. The latter experienced a chain of founder events, which presumably would further reduce genetic diversity and mating capability. Consequently, some archaeological populations lack the genetic ability to sexually reproduce, likely as the result of human-caused founder effect.


Assuntos
Solanum , Efeito Fundador , Geografia , Humanos , Melhoramento Vegetal , Polinização , Reprodução , Solanum/genética
10.
Int J Mol Sci ; 22(6)2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33802058

RESUMO

Citrus Huanglongbing (HLB) disease or citrus greening is caused by Candidatus Liberibacter asiaticus (Las) and is the most devastating disease in the global citrus industry. Salicylic acid (SA) plays a central role in regulating plant defenses against pathogenic attack. SA methyltransferase (SAMT) modulates SA homeostasis by converting SA to methyl salicylate (MeSA). Here, we report on the functions of the citrus SAMT (CsSAMT1) gene from HLB-susceptible Wanjincheng orange (Citrus sinensis (L.) Osbeck) in plant defenses against Las infection. The CsSAMT1 cDNA was expressed in yeast. Using in vitro enzyme assays, yeast expressing CsSAMT1 was confirmed to specifically catalyze the formation of MeSA using SA as a substrate. Transgenic Wanjincheng orange plants overexpressing CsSAMT1 had significantly increased levels of SA and MeSA compared to wild-type controls. HLB resistance was evaluated for two years and showed that transgenic plants displayed significantly alleviated symptoms including a lack of chlorosis, low bacterial counts, reduced hyperplasia of the phloem cells, and lower levels of starch and callose compared to wild-type plants. These data confirmed that CsSAMT1 overexpression confers an enhanced tolerance to Las in citrus fruits. RNA-seq analysis revealed that CsSAMT1 overexpression significantly upregulated the citrus defense response by enhancing the transcription of disease resistance genes. This study provides insight for improving host resistance to HLB by manipulation of SA signaling in citrus fruits.


Assuntos
Citrus sinensis/genética , Resistência à Doença/genética , Metiltransferases/genética , Doenças das Plantas/genética , Proteínas de Plantas/genética , Sequência de Aminoácidos , Citrus sinensis/microbiologia , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Liberibacter/fisiologia , Metiltransferases/metabolismo , Doenças das Plantas/microbiologia , Folhas de Planta/genética , Folhas de Planta/metabolismo , Folhas de Planta/microbiologia , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , RNA-Seq/métodos , Ácido Salicílico/metabolismo , Homologia de Sequência de Aminoácidos
11.
J Clin Microbiol ; 58(8)2020 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-32461285

RESUMO

Several point-of-care (POC) molecular tests have received emergency use authorization (EUA) from the Food and Drug Administration (FDA) for the diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The test performance characteristics of the Accula (Mesa Biotech) SARS-CoV-2 POC test need to be evaluated to inform its optimal use. The aim of this study was to assess the test performance of the Accula SARS-CoV-2 test. The performance of the Accula test was assessed by comparing results of 100 nasopharyngeal swab samples previously characterized by the Stanford Health Care EUA laboratory-developed test (SHC-LDT), targeting the envelope (E) gene. Assay concordance was assessed by overall percent agreement, positive percent agreement (PPA), negative percent agreement (NPA), and Cohen's kappa coefficient. Overall percent agreement between the assays was 84.0% (95% confidence interval [CI], 75.3 to 90.6%), PPA was 68.0% (95% CI, 53.3 to 80.5%), and the kappa coefficient was 0.68 (95% CI, 0.54 to 0.82). Sixteen specimens detected by the SHC-LDT were not detected by the Accula test and showed low viral load burden, with a median cycle threshold value of 37.7. NPA was 100% (95% CI, 94.2 to 100%). Compared to the SHC-LDT, the Accula SARS-CoV-2 test showed excellent negative agreement. However, positive agreement was low for samples with low viral load. The false-negative rate of the Accula POC test calls for a more thorough evaluation of POC test performance characteristics in clinical settings and for confirmatory testing in individuals with moderate to high pretest probability of SARS-CoV-2 who test negative on Accula.


Assuntos
Betacoronavirus/isolamento & purificação , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Pneumonia Viral/diagnóstico , Testes Imediatos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Betacoronavirus/genética , COVID-19 , Teste para COVID-19 , Criança , Pré-Escolar , Infecções por Coronavirus/virologia , Reações Falso-Negativas , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Nasofaringe/virologia , Pandemias , Pneumonia Viral/virologia , RNA Viral/genética , SARS-CoV-2 , Sensibilidade e Especificidade , Adulto Jovem
12.
Arch Biochem Biophys ; 680: 108228, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31843643

RESUMO

Myosin II molecules in the thick filaments of striated muscle form a structure in which the heads interact with each other and fold back onto the tail. This structure, the "interacting heads motif" (IHM), provides a mechanistic basis for the auto-inhibition of myosin in relaxed thick filaments. Similar IHM interactions occur in single myosin molecules of smooth and nonmuscle cells in the switched-off state. In addition to the interaction between the two heads, which inhibits their activity, the IHM also contains an interaction between the motor domain of one head and the initial part (subfragment 2, S2) of the tail. This is thought to be a crucial anchoring interaction that holds the IHM in place on the thick filament. S2 appears to cross the head at a specific location within a broader region of the motor domain known as the myosin mesa. Here, we show that the positive and negative charge distribution in this part of the mesa is complementary to the charge distribution on S2. We have designated this the "mesa trail" owing to its linear path across the mesa. We studied the structural sequence alignment, the location of charged residues on the surface of myosin head atomic models, and the distribution of surface charge potential along the mesa trail in different types of myosin II and in different species. The charge distribution in both the mesa trail and the adjacent S2 is relatively conserved. This suggests a common basis for IHM formation across different myosin IIs, dependent on attraction between complementary charged patches on S2 and the myosin head. Conservation from mammals to insects suggests that the mesa trail/S2 interaction plays a key role in the inhibitory function of the IHM.


Assuntos
Miosina Tipo II/metabolismo , Animais , Aracnídeos/química , Aracnídeos/metabolismo , Proteínas de Artrópodes/química , Proteínas de Artrópodes/metabolismo , Dictyostelium/química , Dictyostelium/metabolismo , Insetos , Mamíferos , Modelos Moleculares , Miosina Tipo II/química , Domínios e Motivos de Interação entre Proteínas , Proteínas de Protozoários/química , Proteínas de Protozoários/metabolismo , Especificidade da Espécie
13.
Biol Lett ; 16(11): 20200631, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33142088

RESUMO

The Upper Triassic tetrapod fossil record of North America features a pronounced discrepancy between the assemblages of present-day Virginia and North Carolina relative to those of the American Southwest. While both are typified by large-bodied archosaurian reptiles like phytosaurs and aetosaurs, the latter notably lacks substantial representation of mammal relatives, including cynodonts. Recently collected non-mammalian eucynodontian jaws from the middle Norian Blue Mesa Member of the Chinle Formation in northeastern Arizona shed light on the Triassic cynodont record from western equatorial Pangaea. Importantly, they reveal new biogeographic connections to eastern equatorial Pangaea as well as southern portions of the supercontinent. This discovery indicates that the faunal dissimilarity previously recognized between the western and eastern portions of equatorial Pangaea is overstated and possibly reflects longstanding sampling biases, rather than a true biogeographic pattern.


Assuntos
Fósseis , Mamíferos , Animais , América do Norte , North Carolina , Virginia
14.
Br J Nutr ; 121(11): 1294-1302, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30375292

RESUMO

A growing number of studies suggest that diet and renal function are related. However, little is known about the link between both whole grain (WG) and refined grain (RG) consumption and kidney function parameters. Thus, we investigated the association of WG and RG with urinary albumin to creatinine ratio (ACR) and prevalent chronic kidney disease (CKD). Data from participants of the National Health and Nutrition Examination Surveys (NHANES) from 2005 to 2010 were collected. Estimated glomerular filtration rate (eGFR) was calculated by the CKD Epidemiology Collaboration equation. Survey design and sample weights were taken into consideration for statistical analyses. Finally, we included 16 325 participants from NHANES, 6·9 % of whom had prevalent CKD. In models adjusted for age, sex, race, fasting blood glucose, blood pressure, adiposity, hypertension and diabetes status, mean eGFR significantly increased across increasing quartiles of WG (Q1: 88·2 v. Q4: 95·4 ml/min per 1·73 m2, P<0·001), whereas it significantly decreased across increasing quartiles of RG (Q1: 97·2 v. Q4: 88·4 ml/min per 1·73 m2, P<0·001). Furthermore, serum uric acid levels and ACR significantly decreased across quartiles of WG (both P<0·001). In multivariable-adjusted logistic regression models, the likelihood of prevalent CKD was 21 % lower in the highest WG quartile compared with the lowest one. In conclusion, our results shed light on the beneficial impact of WG on kidney function and CKD, whereas RG is adversely associated with eGFR.


Assuntos
Dieta/efeitos adversos , Grão Comestível , Insuficiência Renal Crônica/epidemiologia , Grãos Integrais , Adulto , Idoso , Albuminas/análise , Albuminúria/urina , Creatinina/urina , Estudos Transversais , Dieta/métodos , Feminino , Taxa de Filtração Glomerular , Humanos , Testes de Função Renal , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Prevalência , Insuficiência Renal Crônica/etiologia , Fatores de Risco , Ácido Úrico/sangue
15.
Cryobiology ; 90: 100-102, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31419408

RESUMO

Data of cryoprotectant-free vitrification of human testicular and epididymal spermatozoa are limited. The aim of this investigation was to compare two aseptic technologies of TESE (testicular) and MESA (epididymal) spermatozoa cryopreservation: standard conventional freezing with the use of cryoprotectants and cryoprotectant-free vitrification. Sperm motility, capacitation-like changes, acrosome reaction and the mitochondrial membrane potential of frozen (5% glycerol, -10 °C/min) and vitrified (Human Tubal Fluid + 1% Human Serum Albumin+0.25 M sucrose, plunging into liquid nitrogen of capillaries with spermatozoa isolated from liquid nitrogen (aseptic method) were compared. The quality of the cryoprotectant-free vitrified MESA- and TESE-spermatozoa was higher than that of spermatozoa conventionally frozen with permeable cryoprotectants. Intracellular sperm injection (ICSI) was performed with vitrified spermatozoa. We report the birth of three healthy babies from two women following ICSI with motile MESA- and TESE-spermatozoa vitrified without cryoprotectants. This is the first report of full-term pregnancies and babies born after ICSI with epididymal and testicular spermatozoa vitrified without cryoprotectants. In conclusion, cryoprotectant-free vitrification can be successfully applied for the cryopreservation of motile TESE- and MESA-spermatozoa.


Assuntos
Crioprotetores/farmacologia , Epididimo/citologia , Preservação do Sêmen/métodos , Testículo/citologia , Vitrificação/efeitos dos fármacos , Reação Acrossômica/fisiologia , Adulto , Criopreservação/métodos , Transferência Embrionária , Feminino , Congelamento , Humanos , Nascido Vivo , Masculino , Potencial da Membrana Mitocondrial/fisiologia , Gravidez , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/fisiologia , Sacarose
16.
Andrologia ; 51(4): e13217, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30569603

RESUMO

Low sperm quality has negative effects on fertilisation and embryo development. The males with azoospermia apply for testicular sperm extraction (TESE) or microsurgical epididymal sperm aspiration (MESA) in order to retrieve sperm. To date, there have not been any reports investigating morphokinetic parameters of pre-implantation embryos using testicular and epididymal spermatozoa. Therefore, we aimed to correlate embryo development and assess morphogenetic parameters in embryos obtained by TESE and MESA using time-lapse imaging. A total of 60 patients undergoing IVF treatments were included in this study. Twenty men with normal semen parameters were selected as control group. Twenty men undergoing TESE and 20 men undergoing MESA were also included in this study. The morphokinetic parameters of time intervals between the second polar body (PB2) extrusion, pronuclei formation and disappearance and cleavage divisions showed significant variations in TESE, MESA and control groups. Furthermore, the pregnancy rates (positive beta-hCG) were shown to be similar in both TESE and the control group (55% in each group), whereas for the MESA group, this rate was significantly lower (39%, p = 0.049). Further extrapolation of these results may implicate that the obstructive azoospermia patients should undergo TESE instead of MESA for better blastocyst development and higher pregnancy rates.


Assuntos
Azoospermia/terapia , Desenvolvimento Embrionário/fisiologia , Injeções de Esperma Intracitoplásmicas/métodos , Recuperação Espermática , Imagem com Lapso de Tempo , Adulto , Blastocisto/fisiologia , Epididimo/cirurgia , Feminino , Humanos , Masculino , Microcirurgia/métodos , Gravidez , Taxa de Gravidez , Estudos Retrospectivos , Espermatozoides/fisiologia , Testículo/cirurgia , Resultado do Tratamento
18.
J Sci Food Agric ; 99(10): 4816-4824, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30980406

RESUMO

BACKGROUND: In some cultivars, yellowing resulting from chlorophyll breakdown has a direct and negative effect on food supply and health. The 'Zaosu' pear (Pyrus bretschneideri Rehd.), a commercial Asian pear cultivar in China, rapidly turns yellow when stored at room temperature after harvest. To develop techniques that delay or suppress chlorophyll degradation, the effects of methyl salicylate (MeSA) on yellowing in 'Zaosu' pear fruit during storage were evaluated. RESULTS: Compared with the untreated fruit, the application of 0.05 mmol L-1 MeSA delayed the decline of the total chlorophyll, chlorophyll a and chlorophyll b content, and maintained more intact chloroplasts with fewer and smaller plastoglobuli. Methyl salicylate suppressed enzyme activities, including chlorophyllase, chlorophyll-degrading peroxidase, Mg dechelatase, and pheophytinase, and the expression levels of NYC, NOL, CLH, SGR, PPH, PAO and RCCR in treated fruit. CONCLUSION: Methyl salicylate could delay chlorophyll breakdown in the fruit. The results also suggested that the conversion from chlorophyll a to pheophorbide a could proceed via two pathways, and that alternative pathways for the breakdown of chlorophyll a exist in 'Zaosu' pears. © 2019 Society of Chemical Industry.


Assuntos
Clorofila A/metabolismo , Clorofila/metabolismo , Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Pyrus/efeitos dos fármacos , Salicilatos/farmacologia , Clorofila/análise , Clorofila A/análise , Cloroplastos/efeitos dos fármacos , Cloroplastos/metabolismo , Cloroplastos/ultraestrutura , Armazenamento de Alimentos , Frutas/efeitos dos fármacos , Frutas/metabolismo , Frutas/ultraestrutura , Pyrus/metabolismo , Pyrus/ultraestrutura
19.
Br J Nutr ; 120(10): 1159-1170, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30205856

RESUMO

The role that vitamin D plays in pulmonary function remains uncertain. Epidemiological studies reported mixed findings for serum 25-hydroxyvitamin D (25(OH)D)-pulmonary function association. We conducted the largest cross-sectional meta-analysis of the 25(OH)D-pulmonary function association to date, based on nine European ancestry (EA) cohorts (n 22 838) and five African ancestry (AA) cohorts (n 4290) in the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium. Data were analysed using linear models by cohort and ancestry. Effect modification by smoking status (current/former/never) was tested. Results were combined using fixed-effects meta-analysis. Mean serum 25(OH)D was 68 (sd 29) nmol/l for EA and 49 (sd 21) nmol/l for AA. For each 1 nmol/l higher 25(OH)D, forced expiratory volume in the 1st second (FEV1) was higher by 1·1 ml in EA (95 % CI 0·9, 1·3; P<0·0001) and 1·8 ml (95 % CI 1·1, 2·5; P<0·0001) in AA (P race difference=0·06), and forced vital capacity (FVC) was higher by 1·3 ml in EA (95 % CI 1·0, 1·6; P<0·0001) and 1·5 ml (95 % CI 0·8, 2·3; P=0·0001) in AA (P race difference=0·56). Among EA, the 25(OH)D-FVC association was stronger in smokers: per 1 nmol/l higher 25(OH)D, FVC was higher by 1·7 ml (95 % CI 1·1, 2·3) for current smokers and 1·7 ml (95 % CI 1·2, 2·1) for former smokers, compared with 0·8 ml (95 % CI 0·4, 1·2) for never smokers. In summary, the 25(OH)D associations with FEV1 and FVC were positive in both ancestries. In EA, a stronger association was observed for smokers compared with never smokers, which supports the importance of vitamin D in vulnerable populations.


Assuntos
Envelhecimento , Cardiopatias/genética , Coração/fisiologia , Pneumopatias/genética , Pulmão/fisiologia , Testes de Função Respiratória , Vitamina D/sangue , Adulto , Idoso , População Negra , Estudos Transversais , Feminino , Volume Expiratório Forçado , Genoma Humano , Cardiopatias/prevenção & controle , Humanos , Pneumopatias/prevenção & controle , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Estudos Prospectivos , Análise de Regressão , Fumar , Capacidade Vital , Vitamina D/análogos & derivados , População Branca
20.
Int J Mol Sci ; 19(7)2018 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-29997361

RESUMO

The discovery that mutations in myosin and actin genes, together with mutations in the other components of the muscle sarcomere, are responsible for a range of inherited muscle diseases (myopathies) has revolutionized the study of muscle, converting it from a subject of basic science to a relevant subject for clinical study and has been responsible for a great increase of interest in muscle studies. Myopathies are linked to mutations in five of the myosin heavy chain genes, three of the myosin light chain genes, and three of the actin genes. This review aims to determine to what extent we can explain disease phenotype from the mutant genotype. To optimise our chances of finding the right mechanism we must study a myopathy where there are a large number of different mutations that cause a common phenotype and so are likely to have a common mechanism: a corollary to this criterion is that if any mutation causes the disease phenotype but does not correspond to the proposed mechanism, then the whole mechanism is suspect. Using these criteria, we consider two cases where plausible genotype-phenotype mechanisms have been proposed: the actin "A-triad" and the myosin "mesa/IHD" models.


Assuntos
Actinas/genética , Doenças Musculares/genética , Mutação , Miosinas/genética , Idade de Início , Regulação da Expressão Gênica , Humanos , Músculo Esquelético/fisiopatologia , Doenças Musculares/fisiopatologia , Fenótipo
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