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1.
J Am Chem Soc ; 146(14): 9631-9639, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38530981

RESUMO

The induced structural transformation provides an efficient way to precisely modulate the fine structures and the corresponding performance of gold nanoclusters, thus constituting one of the important research topics in cluster chemistry. However, the driving forces and mechanisms of these processes are still ambiguous in many cases, limiting further applications. In this work, based on the unique coordination mode of the pincer ligand-stabilized gold nanocluster Au8(PNP)4, we revealed the site-recognition mechanism for induced transformations of gold nanoclusters. The "open nitrogen sites" on the surface of the nanocluster interact with different inducers including organic compounds and metals and trigger the conversion of Au8(PNP)4 to Au13 and Au9Ag4 nanoclusters, respectively. Control experiments verified the site-recognition mechanism, and the femtosecond and nanosecond transient absorption spectroscopy revealed the electronic and photoluminescent evolution accompanied by the structural transformation.

2.
Nano Lett ; 23(1): 235-242, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-36574348

RESUMO

The emerging metal nanocluster provides a platform for the investigation of structural features, unique properties, and structure-property correlation of nanomaterials at the atomic level. Construction of open sites on the surface of the metal nanocluster is a long-pursued but challenging goal. Herein, we realized the construction of "open organic sites" in a metal nanocluster for the first time. Specifically, we introduce the PNP (2,6-bis(diphenylphosphinomethyl)pyridine) pincer ligand in the synthesis of the gold nanocluster, enabling the construction of a structurally precise Au8(PNP)4 nanocluster. The rigidity and the unique bonding mode of PNP lead to open nitrogen sites on the surface of the Au8(PNP)4 nanocluster, which have been utilized as multifunctional sites in this work for efficient kinetic resolution and catalysis. The gold pincer nanocluster and the open nitrogen site-induced performance will be enlightening for the construction of multifunctional metal nanoclusters.


Assuntos
Nanopartículas Metálicas , Nanoestruturas , Ouro/química , Nanopartículas Metálicas/química , Nanoestruturas/química , Catálise
3.
J Am Chem Soc ; 145(22): 12164-12172, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37235477

RESUMO

Atomically precise metal nanoclusters have received tremendous attention due to their unique structures and properties. Although synthetic approaches to this kind of nanomaterial have been well developed, methods toward precision functionalization of the as-synthesized metal nanoclusters are extremely limited, hindering their interfacial modification and related performance improvement. Herein, an amidation strategy has been developed for the precision functionalization of the Au11 nanocluster based on preorganized nitrogen sites. The nanocluster amidation did not change the number of gold atoms in the Au11 kernel and their bonding mode to the surface ligands but slightly modified the arrangement of gold atoms with the introduction of functionality and chirality, thus representing a relatively mild method for the modification of metal nanoclusters. The stability and oxidation barrier of the Au11 nanocluster are also improved accordingly. The method developed here would be a generalizable strategy for the precision functionalization of metal nanoclusters.

4.
Int J Qual Health Care ; 35(1)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36527417

RESUMO

BACKGROUND: There is an overall decreasing trend in stroke incidence and an increasing trend in its prevalence. Disease burden of stroke continues to increase with an increase in the absolute number. In-depth analysis of stroke burden trends in remote areas is extremely important. Our aim was to describe the disease burden of and risk factors for stroke in Yunnan, from 1990 to 2017. METHODS: The methodological framework and analytical strategies adopted in the 2017 Global Burden of Disease study were used. RESULTS: Age-standardized mortality associated with stroke decreased from 1.53 per 100 000 in 1990 to 1.14 per 100 000 in 2017. The prevalence of stroke in Yunnan Province increased from 344 per 100 000 in 1990 to 870 per 100 000 in 2017. The age-standardized rates of years of life lost (YLLs), years lived with disability (YLDs) and disability-adjusted life years (DALYs) decreased more significantly for women than for men. The age-standardized rates of DALYs and YLLs of stroke decreased by 24.3 and 28.4%, respectively, from 1990 to 2017, and the rate of YLDs increased by 32.5%. The top three risk factors for stroke were dietary risks, high systolic blood pressure and tobacco consumption, and their percentage contributions to the DALYs of stroke were 67.5, 51.5 and 29.1%, respectively. CONCLUSIONS: The burden of stroke has increased in Yunnan since 1990. The health department should emphasize on the changes of stroke risk factors and advocate healthy diet and living habits for residents.


Assuntos
Pessoas com Deficiência , Acidente Vascular Cerebral , Feminino , Humanos , Masculino , China/epidemiologia , Anos de Vida Ajustados por Qualidade de Vida , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Efeitos Psicossociais da Doença
5.
Int J Mol Sci ; 24(19)2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37834012

RESUMO

Triple-negative breast cancer (TNBC) is the most fatal subtype of breast cancer; however, effective treatment strategies for TNBC are lacking. Therefore, it is important to explore the mechanism of TNBC metastasis and identify its therapeutic targets. Dysregulation of ETHE1 leads to ethylmalonic encephalopathy in humans; however, the role of ETHE1 in TNBC remains elusive. Stable cell lines with ETHE1 overexpression or knockdown were constructed to explore the biological functions of ETHE1 during TNBC progression in vitro and in vivo. Mass spectrometry was used to analyze the molecular mechanism through which ETHE1 functions in TNBC progression. ETHE1 had no impact on TNBC cell proliferation and xenograft tumor growth but promoted TNBC cell migration and invasion in vitro and lung metastasis in vivo. The effect of ETHE1 on TNBC cell migratory potential was independent of its enzymatic activity. Mechanistic investigations revealed that ETHE1 interacted with eIF2α and enhanced its phosphorylation by promoting the interaction between eIF2α and GCN2. Phosphorylated eIF2α in turn upregulated the expression of ATF4, a transcriptional activator of genes involved in cell migration and tumor metastasis. Notably, inhibition of eIF2α phosphorylation through ISRIB or ATF4 knockdown partially abolished the tumor-promoting effect of ETHE1 overexpression. ETHE1 has a functional and mechanistic role in TNBC metastasis and offers a new therapeutic strategy for targeting ETHE1-propelled TNBC using ISRIB.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/patologia , Fator de Iniciação 2 em Eucariotos/metabolismo , Linhagem Celular Tumoral , Transdução de Sinais , Proliferação de Células/genética , Movimento Celular/genética , Regulação Neoplásica da Expressão Gênica , Proteínas Mitocondriais/metabolismo , Proteínas de Transporte Nucleocitoplasmático/metabolismo , Fator 4 Ativador da Transcrição/genética , Fator 4 Ativador da Transcrição/metabolismo
6.
Rev Cardiovasc Med ; 23(9): 317, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39077721

RESUMO

Background: The atherosclerotic cardiovascular disease (ASCVD) is a major killer and health care burden worldwide. Atherosclerosis, the common pathological foundation, has been associated with inflammation over the past few years. Some promising results also have emerged suggesting the role of targeting inflammation as a potential therapeutic option to reduce cardiovascular events. In light of the pathogenic role that inflammation plays in ASCVD, we propose to evaluate the worldwide research architecture for ASCVD and inflammation using bibliometric analysis. Methods: A search of the Web of Science Core Collection of Clarivate Analytics was performed for articles in the field published between 2012 and 2022. The number of publications per year has been visualized using GraphPad Prism through time. CiteSpace and VOSviewer were used to generate knowledge maps about the collaboration of countries, institutions, and authors, and to represent the landscape on ASCVD and inflammation research as well as to reveal current foci. Results: There were a total of 19,053 publications examined in this study. The most publications came from China (6232, 32.71%). Capital Med Univ was the most productive institution (410, 2.15%). Christian Weber published the greatest number of articles (75, 0.39%). PloS one was identified as the most prolific journal (706, 3.71%). Circulation was the most co-cited journal (13276, 2.81%). Keywords with the ongoing strong citation bursts were "nucleotide-binding oligomerization (NOD), Leucine-rich repeat (LRR)-containing protein (NLRP3) inflammasome", "intestinal microbiota", "exosome", "lncRNAs", etc. Conclusions: It can be shown that ASCVD and inflammation research benefited from manuscripts that had a high impact on the scientific community. Asian, European and North American countries dominated in the field in terms of quantitative, qualitative and collaborative parameters. The NLRP3 inflammasome, gut microbiota and trimethylamine N-oxide, autophagy, lncRNAs, exosomes, and nuclear factor erythroid 2-related factor 2 were described to be hot themes in the field.

7.
Endocr Pract ; 27(9): 874-880, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33705973

RESUMO

OBJECTIVE: The clinical significance of the YY1 gene mutation and expression in pancreatic neuroendocrine tumors (PNETs) remains unknown. Therefore, this study aimed to comprehensively analyze the somatic mutation of YY1 in the different subtypes of PNETs. METHODS: A total of 143 PNETs were assessed by Sanger sequencing to identify the somatic mutation of YY1 gene in various subtypes of PNETs. YY1 protein expression was examined in 103 PNETs by immunohistochemical staining and western blot. Gene mutation and its protein expression were correlated with clinicopathologic features. RESULTS: A recurrent mutation (chr14:100743807C>G) in the YY1 gene was identified in 15 of 83 insulinomas (18%) and in only 1 of 60 noninsulinoma PNETs (1.7%) (P = .0045). The YY1 mutation was not found in MEN1-associated insulinomas. The YY1 mutation in insulinomas was correlated with older age and lower serum glucose levels (age, 57 vs 42.5 years, P = .006; blood glucose, 25.2 vs 33.6 mg/dL, P = .008). YY1 protein expression was found in 100 of 103 PNETs, although expression was weaker in metastases than in localized tumors (P = .036). The stronger expression of YY1 protein was associated with favorable disease-free survival of patients with PNETs (log-rank, P = .011; n = 70). Multivariable statistical analysis showed that YY1 protein expression could be an independent predictor of prognosis. CONCLUSION: The hotspot YY1 mutation mostly occurred in insulinomas and rarely in noninsulinoma PNETs. The stronger YY1 protein expression was correlated with the better prognosis of PNETs patients.


Assuntos
Insulinoma , Tumores Neuroendócrinos , Neoplasias Pancreáticas , Fator de Transcrição YY1 , Idoso , Humanos , Pessoa de Meia-Idade , Mutação , Tumores Neuroendócrinos/genética , Neoplasias Pancreáticas/genética , Prognóstico , Fator de Transcrição YY1/genética
8.
Mol Hum Reprod ; 26(5): 327-339, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32186736

RESUMO

The study explores the role of neddylation in early trophoblast development and its alteration during the pathogenesis of recurrent spontaneous abortion (RSA). Immunofluorescence and western blot were conducted to evaluate the expression pattern of NEDD8 protein in the first-trimester placentas of healthy control and RSA patients. Neddylated-cullins, especially neddylated-cullin1, were downregulated and their substrate, p21, was accumulated in RSA samples. NEDD8 cytoplasmic recruitment was observed in extravillous trophoblast (EVT) progenitors of RSA placentas. Consistent with the results of clinical samples, neddylation inhibition using MLN4924 in trophoblast cell lines caused obvious p21 accumulation and free NEDD8 cytoplasmic recruitment. Further in vitro study demonstrated neddylation inhibition attenuated proliferation of Jeg-3 cells via p21 accumulation. Moreover, when trophoblast stem (TS) cells derived from first-trimester placentas were cultured for differentiation analyses. MLN4924 impaired the differentiation of TS cells towards EVTs by downregulating HLA-G and GATA3. p21 knockdown could partly rescue MLN4924-suppressed HLA-G and GATA3 expression. In conclusion, cullin1 neddylation-mediated p21 degradation is required for trophoblast proliferation and can affect trophoblast plasticity by affecting HLA-G and GATA3 expression. The results provide insights into the pathological mechanism of RSA and the biological regulation of trophoblast development.


Assuntos
Aborto Habitual/patologia , Proteínas Culina/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Proteína NEDD8/metabolismo , Trofoblastos/fisiologia , Aborto Habitual/genética , Aborto Habitual/metabolismo , Estudos de Casos e Controles , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Células Cultivadas , Proteínas Culina/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , Ciclopentanos/farmacologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Proteína NEDD8/antagonistas & inibidores , Proteína NEDD8/genética , Gravidez , Pirimidinas/farmacologia , RNA Interferente Pequeno/farmacologia , Trofoblastos/efeitos dos fármacos , Trofoblastos/patologia , Ubiquitinação/efeitos dos fármacos , Ubiquitinação/genética
9.
BMC Surg ; 20(1): 265, 2020 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-33129308

RESUMO

BACKGROUND: The clinical outcomes of patients who received distal pancreatectomy with splenectomy (DPS) and spleen-preserving distal pancreatectomy (SPDP) have been generally investigated. However, postoperative hematological changes after distal pancreatectomy with or without splenectomy are poorly understood. METHODS: Information from patients undergoing distal pancreatectomy (DP) between January 2014 and June 2019 at a single institution was reviewed. A linear mixed-effects model was used to compare dynamic hematological changes between different groups. RESULTS: A total of 302 patients who underwent DP were enrolled. In the long term, most postoperative hematological parameters remained significantly higher than preoperative levels in the DPS group, while postoperative lymphocyte, monocyte, basophil, and platelet levels returned to preoperative levels in the SPDP group. All postoperative hematological parameters except for red blood cell count and serum hemoglobulin level were significantly higher in the DPS group than in the SPDP group. There were no significant differences in hematological changes between the splenic vessel preservation (SVP) and Warshaw technique (WT) groups. CONCLUSIONS: Postoperative hematological changes were significantly different between the DPS and SPDP groups. Compared to DPS, SPDP reduced abnormal hematological changes caused by splenectomy. SVP and WT were comparable in terms of postoperative hematological changes.


Assuntos
Pancreatectomia , Neoplasias Pancreáticas , Esplenectomia , Estudos de Coortes , Feminino , Doenças Hematológicas/sangue , Doenças Hematológicas/diagnóstico , Doenças Hematológicas/etiologia , Testes Hematológicos , Humanos , Laparoscopia , Masculino , Pancreatectomia/efeitos adversos , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/cirurgia , Esplenectomia/efeitos adversos , Resultado do Tratamento
10.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 42(2): 270-274, 2020 Apr 28.
Artigo em Zh | MEDLINE | ID: mdl-32385037

RESUMO

Endometrial receptivity has become the main cause of in vitro fertilization and pregnancy outcomes in infertile patients,bringing large psychological damage and economic loss to the patients and their family. In recent years,the role of non-coding RNA has increasingly been recognized. The relationship between non-coding RNA and endometrial receptivity is reviewed in this article.


Assuntos
Endométrio/fisiologia , RNA não Traduzido/genética , Implantação do Embrião , Feminino , Fertilização in vitro , Humanos , Gravidez , Resultado da Gravidez
11.
Zhonghua Nan Ke Xue ; 26(1): 24-30, 2020 Jan.
Artigo em Zh | MEDLINE | ID: mdl-33345473

RESUMO

OBJECTIVE: To investigate the role of the pannexin-1 (Panx1) protein in the invasion and migration of testicular cancer Tcam-2 cells and its possible action mechanism. METHODS: Tcam-2 cells were treated with carbenoxolone (CBX) at 100 µmol/L and probenecid (PBN) 200 µmol/L. Then the intercellular fluorescence transmission was assessed by real-time fluorescence assay, the extracellular ATP concentration measured by chemi-luminescence immunoassay, the invasive and migratory abilities of the Tcam-2 cells detected by Transwell assay, and the expressions of the proteins Panx1, p-ERK1/2, ERK1/2, vimentin, MMP-9 and E-cadherin in the TM3 Leydig cells and testicular cancer Tcam-2 cells determined by Western blot. RESULTS: Western blot showed that the expression of the Panx1 protein was significantly higher in the testicular cancer Tcam-2 cells than in the TM3 Leydig cells (2.79 ± 0.17 vs 1.00 ± 0.06, P<0.05). The rates of intercellular fluorescence transmission in the Tcam-2 cells treated with CBX and PBN were markedly decreased as compared with the blank control group (ï¼»61.54 ± 3.30ï¼½% and ï¼»68.06 ± 4.03ï¼½% vs ï¼»99.50 ± 3.12ï¼½%, P<0.01), and so were the extracellular ATP concentrations (ï¼»57.06 ± 5.80ï¼½% and ï¼»56.42 ± 7.70ï¼½% vs ï¼»110 ± 8.16ï¼½%, P<0.01). The numbers of migrated Tcam-2 cells in the CBX and PBN groups were significantly reduced in comparison with that in the control (11.5 ± 1.11 and 8.25 ± 1.23 vs 331.00 ± 30.80, P<0.05), and so were those of the invaded ones (11.75 ± 3.77 and 11.5 ± 3.5 vs 89.00 ± 13.09, P<0.01). CBX and PBN significantly down-regulated the expression of p-ERK1/2 as compared with that in the blank control group (0.538 ± 0.05 and 0.476 ± 0.02 vs 0.98 ± 0.03, P<0.05), as well as those of vimentin (0.541 ± 0.09 and 0.705 ± 0.07, P<0.01) and MMP-9 (0.439 ± 0.08 and 0.557 ± 0.065, P<0.01) but up-regulated that of E-cadherin (3.896 ± 0.06 and 3.551 ± 0.04, P<0.01). CONCLUSIONS: The Panx1 protein is highly expressed in testicular cancer Tcam-2 cells. CBX and PBN can inhibit the function of the panneixn1 channel and reduce the invasive and migratory abilities of the Tcam-2 cells, which is associated with the decreased expression of the p-ERK1/2 protein.


Assuntos
Movimento Celular , Conexinas/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neoplasias Testiculares/patologia , Carbenoxolona/farmacologia , Linhagem Celular Tumoral , Humanos , Sistema de Sinalização das MAP Quinases , Masculino , Metaloproteinase 9 da Matriz , Probenecid/farmacologia
12.
Cell Commun Signal ; 17(1): 160, 2019 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31796101

RESUMO

Decondesation of the highly compacted chromatin architecture is essential for efficient DNA repair, but how this is achieved remains largely unknown. Here, we report that microrchidia family CW-type zinc finger protein 2 (MORC2), a newly identified ATPase-dependent chromatin remodeling enzyme, is required for nucleosome destabilization after DNA damage through loosening the histone-DNA interaction. Depletion of MORC2 attenuates phosphorylated histone H2AX (γH2AX) focal formation, compromises the recruitment of DNA repair proteins, BRCA1, 53BP1, and Rad51, to sites of DNA damage, and consequently reduces cell survival following treatment with DNA-damaging chemotherapeutic drug camptothecin (CPT). Furthermore, we demonstrate that MORC2 can form a homodimer through its C-terminal coiled-coil (CC) domain, a process that is enhanced in response to CPT-induced DNA damage. Deletion of the C-terminal CC domain in MORC2 disrupts its homodimer formation and impairs its ability to destabilize histone-DNA interaction after DNA damage. Consistently, expression of dimerization-defective MORC2 mutant results in impaired the recruitment of DNA repair proteins to damaged chromatin and decreased cell survival after CPT treatment. Together, these findings uncover a new mechanism for MORC2 in modulating chromatin dynamics and DDR signaling through its c-terminal dimerization.


Assuntos
Cromatina/metabolismo , Fatores de Transcrição/metabolismo , Antineoplásicos Fitogênicos/farmacologia , Camptotecina/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Dano ao DNA , Reparo do DNA , Dimerização , Células HEK293 , Células HeLa , Humanos , Células MCF-7 , Domínios Proteicos , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/deficiência , Fatores de Transcrição/genética
13.
Environ Sci Technol ; 53(3): 1471-1481, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30605315

RESUMO

This work reports the in vivo uptake and translocation of PNPs in the one-year grown terrestrial plant, Murraya exotica ( M. exotica), as investigated by two-photon excitation and time-resolved (TPE-TR) optical imaging with a large field of view (FOV, 32 × 32 mm2) in a noninvasive and real-time manner. The PNPs (⟨ Rh⟩ = 12 ± 4.5 nm) synthesized from poly(styrene- co-maleic anhydride) (SMA) were Eu-luminescence labeled (λL ≈ 617 nm). On exposing the roots of living M. exotica plants to the colloidal suspension of SMA PNPs at different concentrations, the spatiotemporal evolution of SMA PNPs along plant stems (60 mm in length) were monitored by TPE-TR imaging, which rendered rich information on the uptake and translocation of PNPs without any interference from the autofluorescence of the plant tissues. The TPE-TR imaging combined with the high-resolution anatomy revealed an intercell-wall route in the lignified epidermis of M. exotica plants for SMA PNP uptake and translocation, as well as the similar accumulation kinetics at different positions along the plant stems. We modeled the accumulation kinetics with Gaussian distribution to account for the trapping probability of a SMA PNP by the lignified cell walls, allowing the statistical parameters, the average trapping time ( tm) and its variance (σ), to be derived for the quantification of the PNP accumulation in individual plants. The TPE-TR imaging and the analysis protocols established herein will be helpful in exploring the mechanism of plant-PNP interaction under physiological condition.


Assuntos
Murraya , Nanopartículas , Anidridos Maleicos , Imagem Óptica , Estireno
14.
Med Sci Monit ; 25: 3739-3749, 2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-31105262

RESUMO

BACKGROUND Photoaging is the main cause of extrinsic skin aging. Daily exposure to ultraviolet A (UVA) accelerates the process of photoaging. The present study aimed to understand the role of concentrated growth factors (CGF) on UVA irradiated human skin cells. MATERIAL AND METHODS We isolated and subcultured normal human dermal fibroblasts (NHDFs) from 6 different human dorsal skins and established photoaging models of NHDFs irradiated by UVA to detect the influence of CGF on fibroblasts in vitro. Three groups were examined: normal, cellular photoaging model (total dosages of 18J·cm--⁻²-), and cellular photoaging model plus CGF. In our study, we used the MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay method to measure the cell viability. We also used reactive oxygen species (ROS) assay and superoxide dismutase (SOD) assay to measure respectively the amount of oxygen free radicals and antioxidative enzymes. We compared the migration rates among the photoaging model groups, the control groups, and the CGF-treated culture medium groups that were irradiated. RESULTS Our study results indicated that 5% CGF can reduce UVA-induced human skin fibroblasts damage significantly, improve the viability of NHDFs significantly, and largely decrease the UVA irradiation effect (P<0.05). The migration rates of the normal group and the UVA-irradiated NHDFs in the 5% CGF group had significantly increased migration rates (P<0.05), compared to the control medium group. The migration rates of the UVA-irradiated NHDFs in 5% CGF exceed those of the normal group. These results showed that 5% CGF could greatly promote cellular proliferation, migration, and SOD at the same time that the amounts of ROS were markedly decreased. CONCLUSIONS These experimental findings offer some important insights into CGF's capacity for scavenging ROS, improving SOD, and increasing migration rates in NHDFs irradiated by UVA.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Envelhecimento da Pele/patologia , Raios Ultravioleta/efeitos adversos , Antioxidantes/farmacologia , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , China , Derme/efeitos dos fármacos , Fibroblastos/efeitos da radiação , Radicais Livres/metabolismo , Humanos , Cultura Primária de Células , Espécies Reativas de Oxigênio/metabolismo , Pele/efeitos dos fármacos , Superóxido Dismutase/metabolismo
15.
Ecotoxicology ; 27(5): 517-526, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29556939

RESUMO

Seagrasses play an important role in coastal marine ecosystems, but they have been increasingly threatened by human activities. In recent years, seagrass communities have rapidly degenerated in the coastal marine ecosystems of China. To identify the reasons for the decline in seagrasses, the phytotoxic effects of trace metals (Cu, Cd and Zn) on the seagrass Thalassia hemprichii were investigated, and the environmental contents of the metals were analyzed where the seagrass grows. The results showed that leaf necrosis in T. hemprichii exposed to 0.01-0.1 mg L-1 of Cu2+ for 5 days was more serious than that in plants exposed to the same concentrations of Cd2+ and Zn2+. The chlorophyll content in T. hemprichii declined in a concentration-dependent manner after 5 days of exposure to Cu2+, Cd2+ and Zn2+. The evident reduction in ΔF/Fm' in T. hemprichii leaves was observed at day 1 of exposure to 0.01-1.0 mg L-1 of Cu2+ and at day 3 of exposure to 0.1-1.0 mg L-1 of Cd2+. The antioxidant enzyme activities (SOD, POD and CAT) in T. hemprichii leaves exposed to the three metal ions also showed significant changes. In seawater from Xincun Bay (Hainan, China), where T. hemprichii grows, Cu had reached a concentration (i.e., 0.01 mg L-1) that could significantly reduce chlorophyll content and ΔF/Fm' in T. hemprichii leaves. Our results indicate that Cu influences the deterioration of seagrasses in Xincun Bay.


Assuntos
Clorofila/metabolismo , Hydrocharitaceae/efeitos dos fármacos , Fotossíntese , Proteínas de Plantas/metabolismo , Poluentes Químicos da Água/toxicidade , Cádmio/toxicidade , China , Cobre/toxicidade , Monitoramento Ambiental , Fluorescência , Sedimentos Geológicos/análise , Hydrocharitaceae/crescimento & desenvolvimento , Espectrometria de Massas , Fotossíntese/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Dinâmica Populacional , Água do Mar/análise , Zinco/toxicidade
16.
Yi Chuan ; 40(1): 44-56, 2018 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-29367192

RESUMO

As a new branch of genomics, plant paleogenomics reconstructs ancestral genomes from actual modern species and infers palaeohistory, evolutionary and/or speciation events that have shaped the modern species. Advances in high-throughput sequencing technologies yield accurate long reads, promote the progress of plant genome sequence assembly, and thereby offer paleogenomics a large collection of valuable reference genomes from modern species. Whole-genome duplication (WGD) and polyploidization cause rapid genomic reorganization, massive gene losses and structural variations. WGD events are therefore central to plant evolution. In this review, we summarize recent progress in sequencing and assembly of plant genomes, principles of plant paleogenomics, WGD events in plant genomes, and the most likely evolutionary scenario in plants. Furthermore, we highlight some of the challenges as well as future directions.


Assuntos
Genoma de Planta , Evolução Molecular , Duplicação Gênica , Sequenciamento de Nucleotídeos em Larga Escala
17.
BMC Health Serv Res ; 17(1): 395, 2017 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-28599648

RESUMO

BACKGROUND: Pancreatic cancer is rare but highly malignant. Studies have shown that surgeons' knowledge closely links to the correct diagnosis and treatment outcomes of pancreatic cancer. The purpose of this study was to survey current surgeons' knowledge regarding pancreatic cancer. METHODS: A cross-sectional study was conducted among 705 surgeons who attended the 2011 China Surgical Week's meeting in Beijing. A questionnaire regarding the risk factors, clinical manifestations, diagnosis, and treatment of pancreatic cancer was used. Surgeons' answers were analyzed and compared among different regions, levels of hospital, and professional ranks. RESULTS: Most surgeons had a correct knowledge toward the risk factors, diagnosis, and management of pancreatic cancer. However, several knowledge gaps were identified. They include "The association between type 2 diabetes and pancreatic cancer", "The most common histologic type of pancreatic neoplasm", "the typical clinical symptoms of pancreatic cancer", "The accuracy of ultrasound in screening pancreatic cancer", "Enhanced CT in the diagnosis of pancreatic cancer", and "Which is more superior between MRI and CT in the diagnosis of pancreatic cancer". We also found that overall surgeons' responses did not depend on their geographic locations, but on hospital levels and professional ranks. Surgeons working at level three hospitals had better knowledge than others in certain areas and resident surgeons had fewer correct answers in some areas. CONCLUSIONS: Although most surgeons have a good knowledge in most areas related to the diagnosis and treatment of pancreatic cancer in China, certain knowledge gaps exist, particularly among trainees and those from low level hospitals. Continuing medical education programs to improve these knowledge gaps should be implemented.


Assuntos
Competência Clínica/estatística & dados numéricos , Neoplasias Pancreáticas , Cirurgiões , China , Estudos Transversais , Hospitais , Humanos , Internato e Residência , Corpo Clínico Hospitalar , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/etiologia , Neoplasias Pancreáticas/terapia , Fatores de Risco , Inquéritos e Questionários
18.
Health Qual Life Outcomes ; 14: 98, 2016 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-27356505

RESUMO

BACKGROUND: This study aimed to assess ethnic differences in health-related quality of life (HRQoL) among the rural elderly, and to examine the influence of ethnic culture, residential segregation and socioeconomic development on HRQoL. METHODS: A total of 6,511 rural elderly aged 60 years and older from 5,541 households in 116 villages across eight ethnic groups in Guangxi Zhuang Autonomous region were selected and assessed for HRQoL. The EQ-5D index values were calculated based on the Chinese Time Trade-Off values set. The EQ-5D descriptive system scores, visual analogue scale scores, and index values were described by ethnic group. The EQ-5D index was modeled against ethnic culture, residential segregation and socioeconomic development using villages as random effects. RESULTS: The median (IQR) of HRQoL among all the ethnic groups was 0.88 (0.80, 0.96). Pain/discomfort was the most prevalent problem, followed by anxiety/depression. After controlling for sociodemographic characteristics, a significant difference in HRQoL among ethnic groups persisted, but this was not true for residential segregation. CONCLUSION: Social welfare and health policies designed to improve the health of the rural elderly should focus more on older, female, less-educated, Yao minority individuals as well as lower-income households.


Assuntos
Cultura , Nível de Saúde , Qualidade de Vida , População Rural/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , China , Estudos Transversais , Feminino , Humanos , Renda , Masculino , Pessoa de Meia-Idade , Características de Residência , Fatores Socioeconômicos , Inquéritos e Questionários
19.
Phys Chem Chem Phys ; 18(27): 18112-8, 2016 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-27327514

RESUMO

Organolead halide perovskites exhibit superior photoelectric properties, which have given rise to the perovskite-based solar cells whose power conversion efficiency has rapidly reached above 20% in the past few years. However, perovskite-based solar cells have also encountered problems such as current-voltage hysteresis and degradation under practical working conditions. Yet investigations into the intrinsic chemical nature of the perovskite material and its role on the performance of the solar cells are relatively rare. In this work, Raman spectroscopy is employed together with CASTEP calculations to investigate the organic-inorganic interactions in CH3NH3PbI3 and CH3NH3PbBr3-xClx perovskite single crystals with comparison to those having ammonic acid as the cations. For Raman measurements of CH3NH3PbI3, a low energy line of 1030 nm is used to avoid excitation of strong photoluminescence of CH3NH3PbI3. Raman spectra covering a wide range of wavenumbers are obtained, and the restricted rotation modes of CH3-NH3(+) embedded in CH3NH3PbBr3 (325 cm(-1)) are overwhelmingly stronger over the other vibrational bands of the cations. However, the band intensity diminishes dramatically in CH3NH3PbBr3-xClx and most of the bands shift towards high frequency, indicating the interaction with the halides. The details of such an interaction are further revealed by inspecting the band shift of the restricted rotation mode as well as the C-N, NH3(+) and CH3 stretching of the CH3NH3(+) as a function of Cl composition and length of the cationic ammonic acids. The results show that the CH3NH3(+) interacts with the PbX3(-) octahedral framework via the NH3(+) end through N(+)-HX hydrogen bonding whose strength can be tuned by the composition of halides but is insensitive to the size of the organic cations. Moreover, an increase of the Cl content strengthens the hydrogen bonding and thus blueshifts the C-N stretching bands. This is due to the fact that Cl is more electronegative than Br and an increase of the Cl content decreases the lattice constant of the perovskite. The findings of the present work are valuable in understanding the role of cations and halides in the performance of MAPbX3-based perovskite solar cells.

20.
Hepatobiliary Pancreat Dis Int ; 15(1): 30-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26818541

RESUMO

BACKGROUND: Renal cell carcinoma (RCC) is a common cancer, but pancreatic metastasis of RCC is unusual. Because of the rarity and peculiarity, pancreatic lesions from RCC metastasis were described mostly in case reports which highlight the importance of a systematic analysis of this clinical condition. DATA SOURCES: Data of 7 patients with pancreatic metastasis of RCC treated in the Peking Union Medical College Hospital were extracted and 193 similar patients reported in the past 10 years from the literature were analyzed. Epidemiological, pathological and follow-up information were investigated. Potential prognostic factors were compared with corresponding data reported 10 years ago. RESULTS: Multivariate Cox regression showed that asymptomatic metastasis and surgical procedure were independent factors associated with better survival. Compared with the data reported 10 years ago, follow-up of RCC patients has been emphasized in recent years, and atypical surgery is frequently used since it has similar effect as typical surgery on tumor resection while it is able to preserve more pancreatic function. CONCLUSION: Surgical treatment should be an option as long as the pancreatic metastasis of RCC is resectable.


Assuntos
Carcinoma de Células Renais/secundário , Neoplasias Renais/patologia , Neoplasias Pancreáticas/secundário , Idoso , Carcinoma de Células Renais/mortalidade , Carcinoma de Células Renais/cirurgia , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Pancreatectomia , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/cirurgia , Modelos de Riscos Proporcionais , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
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