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1.
Environ Health ; 21(1): 106, 2022 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-36336676

RESUMO

BACKGROUND: The interplay between physical activity (PA) and air pollution in relation to type 2 diabetes (T2D) remains largely unknown. Based on a large population-based cohort study, this study aimed to examine whether the benefits of PA with respect to the risk of T2D are moderated by exposure to air pollution. METHODS: UK Biobank participants (n = 359,153) without diabetes at baseline were included. Information on PA was obtained using the International Physical Activity Questionnaire short form. Exposure to air pollution, including PM2.5, PMcoarse (PM2.5-10), PM10, and NO2, was estimated from land use regression models. Cox regression models were used to estimate the hazard ratios (HRs) and 95% confidence intervals (95% CIs). RESULTS: During a median of 8.9 years of follow-up, 13,706 T2D events were recorded. Compared with a low PA level, the HRs for the risk of T2D among individuals with moderate and high PA were 0.82 (95% CI, 0.79-0.86) and 0.73 (95% CI, 0.70-0.77), respectively. Compared with low levels of air pollution, the HRs for risk of T2D for high levels of air pollution (PM2.5, PMcoarse, PM10, and NO2) were 1.19 (1.14-1.24), 1.06 (1.02-1.11), 1.13 (1.08-1.18), and 1.19 (1.14-1.24), respectively. There was no effect modification of the associations between PA and T2D by air pollution (all P-interactions > 0.05). The inverse associations between PA and T2D in each air pollution stratum were generally consistent (all P for trend < 0.05). CONCLUSION: A higher PA and lower air pollution level were independently associated with a lower risk of T2D. The beneficial effects of PA on T2D generally remained stable among participants exposed to different levels of air pollution. Further studies are needed to replicate our findings in moderately and severely polluted areas.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Diabetes Mellitus Tipo 2 , Humanos , Material Particulado/efeitos adversos , Material Particulado/análise , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Estudos de Coortes , Diabetes Mellitus Tipo 2/epidemiologia , Estudos Prospectivos , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Poluição do Ar/análise , Exercício Físico
2.
Plant J ; 102(4): 747-760, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31863495

RESUMO

Mitogen-activated protein kinase (MAPK) cascades play vital roles in regulating plant growth, development, and stress responses. MAPK-like (MPKL) proteins are a group of kinases containing the MAPK signature TxY motif and showing sequence similarity to MAPKs. However, the functions of plant MPKL proteins are currently unknown. The maize (Zea mays) genome contains four genes encoding MPKL proteins, here named ZmMPKL1 to ZmMPKL4. In this study, we show that ZmMPKL1 possesses kinase activity and that drought-induced ZmMPKL1 expression, ZmMPKL1 overexpression and knockout maize seedlings exhibited no visible morphological difference from wild-type B73 seedlings when grown under normal conditions. By contrast, under drought conditions, ZmMPKL1-overexpressing seedlings showed increased stomatal aperture, water loss, and leaf wilting and knockout seedlings showed the opposite phenotypes. Moreover, these drought-sensitive phenotypes in ZmMPKL1-overexpressing seedlings were restored by exogenous abscisic acid (ABA). ZmMPKL1 overexpression reduced drought-induced ABA production in seedlings and the knockout showed enhanced ABA production. Drought-induced transcription of ABA biosynthetic genes were suppressed and ABA catabolic genes were enhanced in ZmMPKL1-overexpressing seedlings, while their transcription were reversely regulated in knockout seedlings. These results suggest that ZmMPKL1 positively regulates seedlings drought sensitivity by altering the transcription of ABA biosynthetic and catabolic genes, and ABA homeostasis.


Assuntos
Ácido Abscísico/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Zea mays/genética , Sequência de Aminoácidos , Secas , Técnicas de Inativação de Genes , Proteínas Quinases Ativadas por Mitógeno/genética , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plântula/genética , Plântula/crescimento & desenvolvimento , Alinhamento de Sequência , Estresse Fisiológico , Água/metabolismo , Zea mays/crescimento & desenvolvimento , Zea mays/fisiologia
3.
Diabetes Obes Metab ; 23(6): 1361-1370, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33620747

RESUMO

AIMS: To assess the associations of diabetes duration and glycaemic control (defined by plasma glycated haemoglobin [HbA1c] level) with the risks of cardiovascular disease (CVD) and all-cause mortality and to determine whether the addition of either or both to the established CVD risk factors can improve predictions. MATERIALS AND METHODS: A total of 435 679 participants from the UK Biobank without CVD at baseline were included. Cox models adjusting for classic risk factors (sociodemographic and anthropometric characteristics, lipid profiles and medication use) were used, and predictive utility was determined by the C-index and net reclassification improvement (NRI). RESULTS: Compared with participants without diabetes, participants with longer diabetes durations and poorer glycaemic control had a higher risk of fatal/nonfatal CVD. Among participants with diabetes, the fully-adjusted hazard ratios (HRs) for diabetes durations of 5 to <10 years, 10 to <15 years and ≥15 years were 1.15 (95% confidence interval [CI] 0.99, 1.34), 1.50 (95% CI 1.26, 1.79) and 2.22 (95% CI 1.90, 2.58; P-trend <0.01), respectively, compared with participants with diabetes durations <5 years. In addition, those with the longest disease duration (≥15 years) and poorer glycaemic control (HbA1c ≥64 mmol/mol [8%]) had the highest risk of fatal/nonfatal CVD (HR 3.12, 95% CI 2.52, 3.86). Among participants with diabetes, the addition of both diabetes duration and glycaemic control levels significantly improved both the C-index (change in C-index +0.0254; 95% CI 0.0111, 0.0398) and the overall NRI for fatal/nonfatal CVD (0.0992; 95% CI 0.0085, 0.1755) beyond the use of the classic risk factors. CONCLUSIONS: Both longer diabetes duration and poorer glycaemic control were associated with elevated risks of CVD and mortality. Clinicians should consider not only glycaemic control but also diabetes duration in CVD risk assessments for participants with diabetes.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Doenças Cardiovasculares/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Hemoglobinas Glicadas/análise , Controle Glicêmico , Humanos , Fatores de Risco
4.
Plant J ; 96(4): 734-747, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30101424

RESUMO

In Arabidopsis, embryonic development follows a stereotypical pattern of cell division. Although many factors have been reported to participate in establishment of the proper embryonic pattern, the molecular mechanisms underlying pattern formation are unclear. In this study we showed that RAF22 and RAF28, two RAF-like mitogen-activated protein kinase kinase kinases (MAPKKKs) in Arabidopsis, are involved in the regulation of embryogenesis. The double knockout mutant of RAF22 and RAF28 was embryo lethal. A large proportion of the raf22-/- raf28+/- mutant embryos exhibited various defects, including disordered proembryo cell divisions, disruption of the bilaterally symmetrical structure, abnormally formative divisions of hypophysis and exaggerated suspensor growth. Whereas the kinase active form of RAF22 could complement these embryonic aberrant phenotypes, the kinase inactive form could not. The restrictive expression of the basal cell fate marker WOX8 in the abnormally dividing suspensor cells and the apical cell linage marker WOX2 in the abnormal proembryos indicated that apical and basal cell fates were unchanged in the abnormal embryos. The polar distribution of the auxin maxima and the PIN1 and PIN7 auxin transporters was markedly altered in the abnormal embryos. Our results suggest that RAF22 and RAF28 are important components of embryogenesis and that auxin polar transport may be involved in this regulation.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/embriologia , Desenvolvimento Embrionário/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , MAP Quinase Quinase Quinases/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Divisão Celular/genética , Divisão Celular/fisiologia , Desenvolvimento Embrionário/genética , Técnicas de Inativação de Genes , Ácidos Indolacéticos , MAP Quinase Quinase Quinases/genética , Proteínas de Membrana Transportadoras , Fenótipo , Fosfotransferases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Fatores de Transcrição , Transcriptoma
5.
J Exp Bot ; 69(3): 423-439, 2018 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-29244171

RESUMO

Photomorphogenesis is an important process in which seedlings emerge from soil and begin autotrophic growth. Mechanisms of photomorphogenesis include light signal perception, signal transduction, and the modulation of expression of light-responsive genes, ultimately leading to cellular and developmental changes. Phytochrome-interacting factors (PIFs) play negative regulatory roles in photomorphogenesis. Light-induced activation of phytochromes triggers rapid phosphorylation and degradation of PIFs, but the kinases responsible for the phosphorylation of PIFs are largely unknown. Here, we show that Arabidopsis MPK6 is a kinase involved in phosphorylating PIF3 and regulating red light-induced cotyledon opening, a crucial process during seedling photomorphogenesis. MPK6 was activated by red light, and the cotyledon opening angle in red light was reduced in mpk6 seedlings. MKK10, a MAPKK whose function is currently unclear, appears to act as a kinase upstream of MPK6 in regulating cotyledon opening. Activation of MPK6 by MKK10 led to the phosphorylation of PIF3 and accelerated its turnover in transgenic seedlings. Accordingly, the overexpression of PIF3 suppressed MKK10-induced cotyledon opening. MKK10 and MPK6 function downstream of phyB in regulating seedling cotyledon opening in red light. Therefore, the MKK10-MPK6 cascade appears to mediate the regulation of red-light-controlled seedling photomorphogenesis via a mechanism that might involve the phosphorylation of PIF3.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/genética , Plântula/crescimento & desenvolvimento , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/efeitos da radiação , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Cotilédone/genética , Cotilédone/crescimento & desenvolvimento , Cotilédone/metabolismo , Luz , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosforilação , Plântula/genética , Plântula/metabolismo
6.
Nanotechnology ; 29(28): 284002, 2018 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-29667935

RESUMO

Three-dimensional (3D) SnO hierarchical architectures were synthesized via a one-step dissolution-precipitation route under room temperature using SnCl2 · 2H2O and Na2CO3 as the initial reagents. The morphology and size of the prepared SnO structures could be easily tailored by alternating the solvent from deionized water with absolute ethanol. The SEM observation showed that the prepared 3D SnO hierarchical architectures consisted of nanosheets. The size of the SnO hierarchical architectures could be effectively reduced from 4-10 µm to 1-2 µm when the solvent was changed from water to ethanol while the thickness of the assembling nanosheets was reduced from 200-500 nm to 20-30 nm at the same time. The possible formation mechanism of the 3D SnO hierarchical architectures is proposed in this paper. The photodegradation of methylene blue revealed that the SnO hierarchical structures prepared using ethanol as the solvent exhibit much better photocatalytic activity due to its smaller particle size, larger specific surface area, and appropriate band structure as well.

7.
Plant Cell Environ ; 40(8): 1317-1331, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28102910

RESUMO

Previous physiological and pharmacological studies have suggested that the activity of phosphoinositide-specific phospholipase C (PI-PLC) plays an important role in regulating plant salt stress responses by altering the intracellular Ca2+ concentration. However, the individual members of plant PLCs involved in this process need to be identified. Here, the function of AtPLC4 in the salt stress response of Arabidopsis seedlings was analysed. plc4 mutant seedlings showed hyposensitivity to salt stress compared with Col-0 wild-type seedlings, and the salt hyposensitive phenotype could be complemented by the expression of native promoter-controlled AtPLC4. Transgenic seedlings with AtPLC4 overexpression (AtPLC4 OE) exhibited a salt-hypersensitive phenotype, while transgenic seedlings with its inactive mutant expression (AtPLC4m OE) did not exhibit this phenotype. Using aequorin as a Ca2+ indicator in plc4 mutant and AtPLC4 OE seedlings, AtPLC4 was shown to positively regulate the salt-induced Ca2+ increase. The salt-hypersensitive phenotype of AtPLC4 OE seedlings was partially rescued by EGTA. An analysis of salt-responsive genes revealed that the transcription of RD29B, MYB15 and ZAT10 was inversely regulated in plc4 mutant and AtPLC4 OE seedlings. Our findings suggest that AtPLC4 negatively regulates the salt tolerance of Arabidopsis seedlings, and Ca2+ may be involved in regulating this process.


Assuntos
Arabidopsis/enzimologia , Arabidopsis/fisiologia , Fosfoinositídeo Fosfolipase C/metabolismo , Tolerância ao Sal , Plântula/fisiologia , Sequência de Aminoácidos , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Sinalização do Cálcio/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Modelos Biológicos , Mutação/genética , Fosfoinositídeo Fosfolipase C/química , Tolerância ao Sal/efeitos dos fármacos , Plântula/efeitos dos fármacos , Sódio/metabolismo , Cloreto de Sódio/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Fatores de Tempo , Transcrição Gênica/efeitos dos fármacos
8.
J Integr Plant Biol ; 58(8): 724-36, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26822341

RESUMO

Leaf senescence is the final leaf developmental process that is regulated by both intracellular factors and environmental conditions. The mitogen-activated protein kinase (MAPK) signaling cascades have been shown to play important roles in regulating leaf senescence; however, the component(s) downstream of the MAPK cascades in regulating leaf senescence are not fully understood. Here we showed that the transcriptions of ZmMEK1, ZmSIMK1, and ZmMPK3 were induced during dark-induced maize leaf senescence. Furthermore, in-gel kinase analysis revealed the 42 kDa MAPK was activated. ZmMEK1 interacted with ZmSIMK1 in yeast and maize mesophyll protoplasts and ZmSIMK1 was activated by ZmMEK1 in vitro. Expression of a dominant negative mutant of ZmMEK1 in Arabidopsis transgenic plants induced salicylic acid (SA) accumulation and SA-dependent leaf senescence. ZmMEK1 interacted with Arabidopsis MPK4 in yeast and activated MPK4 in vitro. SA treatment accelerated dark-induced maize leaf senescence. Moreover, blockage of MAPK signaling increased endogenous SA accumulation in maize leaves. These findings suggest that ZmMEK1-ZmSIMK1 cascade and its modulating SA levels play important roles in regulating leaf senescence.


Assuntos
Expressão Gênica , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Ácido Salicílico/metabolismo , Zea mays/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Escuridão , Regulação da Expressão Gênica de Plantas , Sistema de Sinalização das MAP Quinases/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosforilação , Plantas Geneticamente Modificadas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Zea mays/enzimologia , Zea mays/genética
9.
New Phytol ; 203(4): 1146-1160, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24865627

RESUMO

Despite the abundance of phosphorus in soil, very little is available as phosphate (Pi) for plants. Plants often experience low Pi (LP) stress. Intensive studies have been conducted to reveal the mechanism used by plants to deal with LP; however, Pi sensing and signal transduction pathways are not fully understood. Using in-gel kinase assays, we determined the activities of MPK3 and MPK6 in Arabidopsis thaliana seedlings under both LP and Pi-sufficient (Murashige and Skoog, MS) conditions. Using MKK9 mutant transgenic and crossed mutants, we analyzed the functions of MPK3 and MPK6 in regulating Pi responses of seedlings. The regulation of Pi responses by downstream components of MKK9-MPK3/MPK6 was also screened. LP treatment activated MPK3 and MPK6. Under both LP and MS conditions, mpk3 and mpk6 seedlings took up and accumulated less Pi than the wild-type; activation of MKK9-MPK3/MPK6 in transgenic seedlings induced the transcription of Pi acquisition-related genes and enhanced Pi uptake and accumulation, whereas its activation suppressed the transcription of anthocyanin biosynthetic genes and anthocyanin accumulation; WRKY75 was downstream of MKK9-MPK3/MPK6 when regulating the accumulation of Pi and anthocyanin, and the transcription of Pi acquisition-related and anthocyanin biosynthetic genes. These results suggest that the MKK9-MPK3/MPK6 cascade is part of the Pi signaling pathway in plants.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Arabidopsis/metabolismo , Fosfatos/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Ativação Enzimática/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Modelos Biológicos , Proteínas Mutantes/metabolismo , Fosfatos/deficiência , Fosfatos/farmacologia , Plantas Geneticamente Modificadas , Plântula/enzimologia , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética , Transcrição Gênica/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
10.
Plant Cell ; 23(1): 364-80, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21239642

RESUMO

Camalexin, a major phytoalexin in Arabidopsis thaliana, consists of an indole ring and a thiazole ring. The indole ring is produced from Trp, which is converted to indole-3-acetonitrile (IAN) by CYP79B2/CYP79B3 and CYP71A13. Conversion of Cys(IAN) to dihydrocamalexic acid and subsequently to camalexin is catalyzed by CYP71B15. Recent studies proposed that Cys derivative, not Cys itself, is the precursor of the thiazole ring that conjugates with IAN. The nature of the Cys derivative and how it conjugates to IAN and subsequently forms Cys(IAN) remain obscure. We found that protein accumulation of multiple glutathione S-transferases (GSTs), elevation of GST activity, and consumption of glutathione (GSH) coincided with camalexin production. GSTF6 overexpression increased and GSTF6-knockout reduced camalexin production. Arabidopsis GSTF6 expressed in yeast cells catalyzed GSH(IAN) formation. GSH(IAN), (IAN)CysGly, and γGluCys(IAN) were determined to be intermediates within the camalexin biosynthetic pathway. Inhibitor treatments and mutant analyses revealed the involvement of γ-glutamyl transpeptidases (GGTs) and phytochelatin synthase (PCS) in the catabolism of GSH(IAN). The expression of GSTF6, GGT1, GGT2, and PCS1 was coordinately upregulated during camalexin biosynthesis. These results suggest that GSH is the Cys derivative used during camalexin biosynthesis, that the conjugation of GSH with IAN is catalyzed by GSTF6, and that GGTs and PCS are involved in camalexin biosynthesis.


Assuntos
Arabidopsis/metabolismo , Glutationa/metabolismo , Indóis/metabolismo , Tiazóis/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Técnicas de Inativação de Genes , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mutagênese Insercional , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo
11.
Tumour Biol ; 35(3): 1973-83, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24136744

RESUMO

Lymphotoxin-alpha (LTA) polymorphism rs909253 has been reported to be a risk factor for cancers, but some results are inconsistent. To establish a more conclusive association, we performed a meta-analysis of this variant with cancers. A systematic search was performed for informative case-control studies of rs909253 with cancers among literature databases, including PubMed, Web of Science, Embase, China National Knowledge Infrastructure (CNKI), and Wanfang Chinese Periodical Database. After a comprehensive filtration procedure, 36 publications involved with 35,677 participants were selected for the current meta-analysis. Stratified factors, such as cancer type, populations, and source of control, were used for a better interpretation of this variant. Minimal heterogeneity was shown in the current meta-analysis (I (2) = 0.0%, P = 0.48). Our results show a significant association of rs909253 and cancer risk (odds ratio (OR) = 1.12, P (z) < 0.001). In the subgroup analysis, significant association of rs909253 was found in adenocarcinoma (OR = 1.16, P (z) < 0.001) and hematological malignancy (OR = 1.10, P (z) < 0.001). Our meta-analyses established a significant association of rs909253 with cancer risk among multiple populations including North Americans, Asians, and Europeans.


Assuntos
Predisposição Genética para Doença/genética , Linfotoxina-alfa/genética , Neoplasias/genética , Polimorfismo de Nucleotídeo Único/genética , Estudos de Casos e Controles , Genótipo , Humanos , Fatores de Risco
12.
Plant Cell Environ ; 35(8): 1428-39, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22376201

RESUMO

Sucrose was recently demonstrated to function as a molecular signal. However, sucrose-specific sensing and signalling pathways remain largely undefined. Here, we show that Cephalostachyum fuchsianum sucrose-activated protein kinase (CfSAPK) is transiently and specifically activated by sucrose in C. fuchsianum Gamble suspension cells. The result suggested that CfSAPK participates in a sucrose-signalling pathway. CfSAPK was partially purified from sucrose-treated cells and further analysed. Kinase activity assays revealed that CfSAPK preferentially used myelin basic protein (MBP) as substrate in vitro and strongly phosphorylate MBP threonine residue(s) and weakly phosphorylated MBP serine residue(s). Of the divalent cations tested, Mg(2+) was required for CfSAPK activation. Phosphatase treatment of CfSAPK abolished its kinase activity, indicating that phosphorylation is required for CfSAPK activation. Seven internal tryptic peptides identified from CfSAPK matched mitogen-activated protein kinases (MAPKs) in plants. CfSAPK cDNA was cloned using RT-PCR and rapid amplification of cDNA ends (RACE). CfSAPK cDNA encodes a 382-amino acid protein with a calculated molecular mass of 43,466.9 Da. The CfSAPK protein contains all 11 conserved kinase subdomains found in other Ser/Thr kinases. The amino acids sequence of CfSAPK is highly homologous to group A MAPKs in monocotyledon plants.


Assuntos
Bambusa/enzimologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Sequência de Bases , Primers do DNA , Ativação Enzimática , Fosforilação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Especificidade por Substrato
13.
J Gerontol A Biol Sci Med Sci ; 77(1): 180-187, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33674815

RESUMO

BACKGROUND: Evidence regarding the associations of tooth loss and denture use with incident cognitive impairment is inconclusive in older adults, and few prospective studies have examined the potential interaction between tooth loss and denture use in these specific populations. METHODS: Data were assessed from 17 079 cognitively normal older adults aged ≥65 years, participating in the Chinese Longitudinal Healthy Longevity Survey. The outcome of interest was cognitive impairment (assessed by the Chinese version of Mini-Mental State Examination). The number of natural teeth and status of denture use were collected by a structural questionnaire. RESULTS: A total of 6456 cases of cognitive impairment were recorded during 88 627 person-years of follow-up. We found that compared with participants with 20+ teeth, those with 10-19, 1-9, and 0 teeth had increased risks of incident cognitive impairment (p-trend < .001). Participants without dentures also had a higher risk of incident cognitive impairment, compared with those who wore dentures. Effect modification by denture use was observed (p-interaction = .010). Specifically, among those without dentures, the adjusted hazard ratio (95% confidence interval) for participants with 10-19, 1-9, and 0 teeth were 1.19 (1.08, 1.30), 1.28 (1.17, 1.39), and 1.28 (1.16, 1.41), respectively, as compared to those with 20+ teeth. In contrary, among denture users, detrimental effect was only observed among those with 0 teeth (hazard ratio 1.14, 95% confidence interval: 1.16, 1.41). CONCLUSIONS: In Chinese older adults, maintaining 20+ teeth is important for cognitive health; denture use would attenuate the detrimental effects of tooth loss, especially for partial tooth loss, on cognitive impairment.


Assuntos
Disfunção Cognitiva , Perda de Dente , Idoso , China/epidemiologia , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/etiologia , Estudos de Coortes , Dentaduras/efeitos adversos , Humanos , Estudos Prospectivos , Perda de Dente/epidemiologia
14.
Front Public Health ; 10: 824783, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35211447

RESUMO

BACKGROUND: The association between high-sensitivity C-reactive protein (hsCRP) levels and all-cause mortality for the oldest-old (aged 80 years or older) remains unclear. We aimed to investigate the associations between hsCRP concentrations and the risks of all-cause mortality, and further identify the potential modifying factors affecting these associations among the oldest-old. METHODS: This prospective, community-based cohort study included 2,206 participants aged 80 years or older (median age 93.0 years) from the Healthy Aging and Biomarkers Cohort Study. Cox proportional hazards regression models were used to estimate hazard ratios (HRs) with 95% confidential intervals (95% CIs) for all-cause mortality according to hsCRP quartiles and recommendation for relative risk categories of hsCRP levels (< 1.0, 1.0-3.0, and > 3.0 mg/L), with adjustment for sociodemographic information, lifestyle, physical examination, medical history, and other potential confounders. RESULTS: During a median follow-up period of 3.1 years (IQR: 1.6-3.9 years), 1,106 deaths were verified. After full adjustment for potential confounders, a higher hsCRP concentration was positively associated with an increased risk of all-cause mortality (P for trend < 0.001). Compared with the lowest quartile, the fully adjusted HRs of the second, third, and fourth quartiles were 1.17 (95% CI: 0.94, 1.46), 1.28 (95% CI: 1.01, 1.61), and 1.49 (95% CI: 1.20, 1.87), respectively. The association of hsCRP with all-cause mortality was modified by smoking status (P for interaction = 0.011), an increased risk of hsCRP with all-cause mortality showed among non-current smokers (HR: 1.17; 95% CI: 1.07, 1.28), but no significance was observed in current smokers (HR: 0.83; 95% CI: 0.66, 1.18). CONCLUSIONS: Our study indicated that elevated hsCRP concentrations were associated with a higher risk of all-cause mortality among Chinese oldest-old. Future studies investigating additional factors of disease and aging processes are needed to obtain a better understanding of the mechanisms.


Assuntos
Proteína C-Reativa , Idoso de 80 Anos ou mais , China/epidemiologia , Estudos de Coortes , Humanos , Modelos de Riscos Proporcionais , Estudos Prospectivos
16.
Curr Microbiol ; 62(4): 1113-22, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21132569

RESUMO

Plant growth-promoting bacteria (PGPB) refer to the bacteria beneficial to plants, and they may affect the growth and development of plants directly or indirectly. This article studied the activities of nitrogen fixation and colonization of a strain of PGPB, Klebsiella pneumoniae NG14, which was isolated from the rice root surface. The results showed that NG14 harbouring the nifH gene had nitrogenase activity, (15)N(2)-fixing activity, and was able to colonize on the root surface and within the cavity of root vascular tissues of rice. Using proteomics technology to study the differences and changes of membrane proteins (MP) of NG14 bacterial biofilm in non-biological surface, 28 proteins showing significant differences before and after the formation of bacterial biofilm have been identified, in which the precursors of membrane pore protein OmpC relevant to osmotic stress resistance was up-regulated. This study would have positive significance on further understanding of the direct and indirect promotion effects of PGPB and related mechanisms.


Assuntos
Biofilmes , Klebsiella pneumoniae/crescimento & desenvolvimento , Fixação de Nitrogênio , Oryza/microbiologia , Raízes de Plantas/microbiologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Klebsiella pneumoniae/classificação , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/fisiologia , Dados de Sequência Molecular , Filogenia , Microbiologia do Solo
17.
J Gerontol A Biol Sci Med Sci ; 76(11): 2062-2070, 2021 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-34331763

RESUMO

BACKGROUND: To investigate the influence of diabetes duration and glycemic control, assessed by glycated hemoglobin (HbA1c) levels, on risk of incident dementia. METHODS: The present study is a prospective study of 461 563 participants from the UK Biobank. The age at diabetes diagnosis was determined by self-report. Diabetes duration was calculated as baseline age minus age at diagnosis. Cox proportional hazards regression models were used to estimate hazard ratios (HRs) with 95% confidential intervals (CIs). RESULTS: During a median follow-up of 8.1 years, 2 233 dementia cases were recorded. As compared with normoglycemic individuals, individuals with diabetes had higher risk of all-cause dementia, and the risk increased with increasing duration of diabetes; compared with participants with diabetes duration of <5 years, the multivariable-adjusted HRs (95% CIs) were 1.49 (1.12-1.97), 1.71 (1.21-2.41), and 2.15 (1.60-2.90) for those with diabetes durations ≥5 to < 10, ≥10 to <15, and ≥ 15 years, respectively (p for trend < .001). Among participants with diabetes, those with both longer diabetes duration (diabetes duration ≥ 10 years) and poor glycemic control (HbA1c ≥ 8%) had the highest risk of all-cause dementia (multivariable-adjusted HR = 2.07, 95% CI 1.45, 2.94), compared with patients with shorter duration of diabetes and better glycemic control (diabetes duration < 10 years and HbA1c < 8%). CONCLUSIONS: Diabetes duration appeared to be associated with the risk of incident dementia due to factors beyond glycemic control. Clinicians should consider not only glycemic control but also diabetes duration in dementia risk assessments for patients with diabetes.


Assuntos
Demência , Diabetes Mellitus Tipo 2 , Diabetes Mellitus , Glicemia , Estudos de Coortes , Demência/etiologia , Diabetes Mellitus/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Hemoglobinas Glicadas/análise , Controle Glicêmico , Humanos , Estudos Prospectivos , Fatores de Risco
18.
J Alzheimers Dis ; 80(4): 1591-1601, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33720888

RESUMO

BACKGROUND: Wealth and income are potential modifiable risk factors for dementia, but whether wealth status, which is composed of a combination of debt and poverty, and assessed by wealth and income, is associated with cognitive impairment among elderly adults remains unknown. OBJECTIVE: To examine the associations of different combinations of debt and poverty with the incidence of dementia and cognitive impairment without dementia (CIND) and to evaluate the mediating role of depression in these relationships. METHODS: We included 15,565 participants aged 51 years or older from the Health and Retirement Study (1992-2012) who were free of CIND and dementia at baseline. Dementia and CIND were assessed using either the modified Telephone Interview for Cognitive Status (mTICS) or a proxy assessment. Cox models with time-dependent covariates and mediation analysis were used. RESULTS: During a median of 14.4 years of follow-up, 4,484 participants experienced CIND and 1,774 were diagnosed with dementia. Both debt and poverty were independently associated with increased dementia and CIND risks, and the risks were augmented when both debt and poverty were present together (the hazard ratios [95% confidence intervals] were 1.35 [1.08-1.70] and 1.96 [1.48-2.60] for CIND and dementia, respectively). The associations between different wealth statuses and cognition were partially (mediation ratio range: 11.8-29.7%) mediated by depression. CONCLUSION: Debt and poverty were associated with an increased risk of dementia and CIND, and these associations were partially mediated by depression. Alleviating poverty and debt may be effective for improving mental health and therefore curbing the risk of cognitive impairment and dementia.


Assuntos
Disfunção Cognitiva/epidemiologia , Demência/epidemiologia , Depressão/complicações , Depressão/etiologia , Pobreza/psicologia , Idoso , China/epidemiologia , Feminino , Humanos , Incidência , Estudos Longitudinais , Masculino , Análise de Mediação , Testes de Estado Mental e Demência , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Aposentadoria/psicologia , Fatores de Risco
19.
J Hypertens ; 39(8): 1594-1601, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-33560057

RESUMO

OBJECTIVE: The 2017 American College of Cardiology/American Heart Association blood pressure (BP) guidelines lowered the hypertension threshold from a SBP/DBP level of at least 140/90 mmHg to at least 130/80 mmHg. The cardiovascular impact of isolated systolic hypertension (ISH) and isolated diastolic hypertension (IDH) under the new definition remains unclear. METHODS: We used data from the UK Biobank study, which is a prospective population-based cohort study. Participants were categorized into five groups: normal BP, normal high BP, ISH, IDH and systolic and diastolic hypertension. The primary endpoint for this study was the composite of nonfatal myocardial infarction (MI), nonfatal ischaemic stroke, nonfatal haemorrhagic stroke and cardiovascular disease (CVD) death. We also explored the results for the above-mentioned CVD outcomes separately. Baseline BP measurements were obtained twice after the participant had been at rest for at least 5 min in a seated position. RESULTS: We included 385 955 participants who were not taking antihypertensive medications, were free of CVD at baseline and had available data on BP measurements. During a median follow-up of 8.1 years, 8959 CVD events were recorded, including 4729 nonfatal MIs, 2287 nonfatal ischaemic strokes, 813 nonfatal haemorrhagic strokes, and 1826 CVD deaths. According to the hypertension threshold of at least 130/80 mmHg by the American College of Cardiology/American Heart Association guidelines, both ISH (hazard ratio 1.39; 95% confidence interval 1.27, 1.15) and IDH (hazard ratio 1.28; 95% confidence interval 1.15, 1.43) were significantly associated with a higher overall CVD risk than normal BP. ISH was associated with most CVD risk, except for ischaemic stroke, while the excess CVD risk associated with IDH appeared to be driven mainly by MI and CVD death. We found heterogeneity by sex and age regarding the effects of IDH on overall CVD risk, with significant associations in younger adults (age <60 years) and women and null associations in men and older adults (age ≥60 years). CONCLUSION: ISH was associated with the risk of most CVD events, while the association between IDH and CVD risk was mainly driven by MI incidence and CVD death. Further research is needed to identify participants with IDH who have a particular risk for developing CVD.


Assuntos
Isquemia Encefálica , Cardiologia , Doenças Cardiovasculares , Hipertensão , Acidente Vascular Cerebral , Idoso , American Heart Association , Pressão Sanguínea , Doenças Cardiovasculares/epidemiologia , Estudos de Coortes , Feminino , Humanos , Hipertensão/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Estados Unidos/epidemiologia
20.
J Am Med Dir Assoc ; 22(9): 1946-1952.e3, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33249058

RESUMO

OBJECTIVES: A few studies of Western populations have found inconsistent results regarding the associations between vitamin D status and physical function. We explored the association between circulating vitamin D status [plasma 25-hydroxyvitamin D, 25(OH)D] and incident activities of daily living (ADL) disability among Chinese older adults. DESIGN: Community-based longitudinal cohort study. SETTING AND PARTICIPANTS: A total of 2453 men and women (median age 84.0 years) in 7 Chinese longevity areas were included. MEASURES: Cox proportional hazards regression models were used to estimate hazard ratios (HRs) with 95% confidence intervals (CIs) for incident ADL, with adjustments for potential sociodemographic, and lifestyle confounders and biomarkers. Because there was a statistically significant interaction between plasma 25(OH)D and sex in relation to incident ADL, men and women were analyzed separately. RESULTS: The median concentrations of plasma 25(OH)D were 46.6 nmol/L and 36.4 nmol/L for men and women, respectively. Compared with the lowest quartile in the fully adjusted model, the HR for incident ADL disability for the highest quartile was 0.55 (95% CI 0.36-0.85) for women; for men, a null association was indicated (HRhighest vs lowest 0.61, 95% CI 0.37-1.00). However, when using the recommended circulating 25(OH)D thresholds by the US Institute of Medicine, those with vitamin D sufficiency (≥50 nmol/L) had better ADL disability prognoses than those with vitamin D deficiency (<30 nmol/L) in both sexes (men HR 0.45, 95% CI 0.28-0.72; women HR 0.58, 95% CI 0.37-0.90). CONCLUSIONS AND IMPLICATIONS: The relationship between plasma 25(OH)D concentration and incident ADL disability was sex-specific among Chinese older adults. However, participants with recommended vitamin D sufficiency may have better disability prognoses in both sexes, suggesting that the recommended 25(OH)D concentration for bone health may extend to functional outcomes such as ADL disability in Chinese older adults.


Assuntos
Atividades Cotidianas , Deficiência de Vitamina D , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Estudos Longitudinais , Masculino , Vitamina D/análogos & derivados , Deficiência de Vitamina D/diagnóstico , Deficiência de Vitamina D/epidemiologia
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