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2.
Exp Biol Med (Maywood) ; 245(17): 1552-1559, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32854519

RESUMO

IMPACT STATEMENT: The functional decline of motor activity is a common feature in almost all aging animals that leads to frailty, loss of independence, injury, and even death in the elderly population. Thus, understanding the molecular mechanism that drives the initial stage of this functional decline and developing strategies to increase human healthspan and even lifespan by targeting this process would be of great interests to the field. In this study, we found that by precisely targeting the motor neurons to potentiate its synaptic releases either genetically or pharmacologically, we can not only delay the functional aging at NMJs but also slow the rate of aging at the organismal level. Most importantly, we have demonstrated that a critical window of time, that is the early stage of NMJs functional decline, is required for the beneficial effects. A short-term treatment within this time period is sufficient to extend the animals' lifespan.


Assuntos
Caenorhabditis elegans/fisiologia , Exocitose , Longevidade/fisiologia , Neurônios Motores/fisiologia , Sinapses/fisiologia , Animais , Arecolina/farmacologia , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Exocitose/efeitos dos fármacos , Longevidade/efeitos dos fármacos , Neurônios Motores/efeitos dos fármacos , Receptores Muscarínicos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sinapses/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/genética
3.
Inorg Chem ; 56(14): 7602-7605, 2017 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-28677959

RESUMO

Two new polymorphs of a zinc phosphate incorporating the terephthalate organic ligand 1,4-benzenedicarboxylate (BDC), (H2DA)Zn2(cis-BDC)(HPO4)2 (1) and (H2DA)Zn2(trans-BDC)(HPO4)2 (2), where DA = 1,7-diaminoheptane, were synthesized via a hydro(solvo)thermal method at different reaction temperatures and structurally characterized by single-crystal X-ray diffraction. Interestingly, the BDC ligands, which adopt the bis-monodentate coordination model with a unusual cis type for compound 1 and with a trans linkage for compound 2, bridge the Zn atoms of the inorganic layers in the generation of two polymorphs with structural diversities (one kind of arrangement of the layered zincophosphate layer in 1; the flat and zigzag sheets of inorganic networks in 2). A simple method for tuning the optical luminescence of the title compound from blue, red, green, yellow, and pink to white emission by stirring powdered samples in lanthanide-cation-containing aqueous ethanol solutions at room temperature for 1-2 h is also presented.

4.
PLoS One ; 11(5): e0156059, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27219009

RESUMO

Pigment epithelium-derived factor (PEDF) is a multifunctional protein that exhibits anti-angiogenic, antitumor, anti-inflammatory, antioxidative, anti-atherogenic, and cardioprotective properties. While it was recently shown that PEDF expression is inhibited under low oxygen conditions, the functional role of PEDF in response to hypoxia/reoxygenation (H/R) remains unclear. The goal of this study was to therefore investigate the influence of PEDF on myocardial H/R injury. For these analyses, PEDF-specific small interfering RNA-expressing and PEDF-expressing lentivirus (PEDF-LV) vectors were utilized to knockdown or stably overexpress PEDF, respectively, within human cardiomyocytes (HCM) in vitro. We noted that reactive oxygen species (ROS) play important roles in the induction of cell death pathways, including apoptosis and autophagy in ischemic hearts. Our findings demonstrate that overexpression of PEDF resulted in a significant reduction in ROS production and attenuation of mitochondrial membrane potential depletion under H/R conditions. Furthermore, PEDF inhibited the activation of a two-step apoptotic pathway in which caspase-dependent (caspase-9 and caspase-3) and caspase-independent (apoptosis inducing factor and endonuclease G), which in turn cleaves several crucial substrates including the DNA repair enzyme poly (ADP-ribose) polymerase. Meanwhile, overexpression of PEDF also promoted autophagy, a process that is typically activated in response to H/R. Therefore, these findings suggest that PEDF plays a critical role in preventing H/R injury by modulating anti-oxidant and anti-apoptotic factors and promoting autophagy.


Assuntos
Proteínas do Olho/genética , Proteínas do Olho/metabolismo , Mitocôndrias/fisiologia , Miócitos Cardíacos/citologia , Fatores de Crescimento Neural/genética , Fatores de Crescimento Neural/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Serpinas/genética , Serpinas/metabolismo , Apoptose , Autofagia , Caspases/metabolismo , Hipóxia Celular , Sobrevivência Celular , Células Cultivadas , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Potencial da Membrana Mitocondrial , Modelos Biológicos , Miócitos Cardíacos/metabolismo
5.
Cancer Nurs ; 39(6): E36-E44, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26713500

RESUMO

BACKGROUND: In Taiwan, breast cancer is the most common cancer in women. Most breast cancer patients are willing to receive chemotherapy and experience adverse effects and suffering during the process of chemotherapy. OBJECTIVES: The aim of this study was to explore patients' psychological process when receiving initial chemotherapy for breast cancer. METHODS: A qualitative grounded theory approach was used. Data were collected through semistructured interviews of 20 patients who were from 1 district teaching hospital during 2012 to 2013. RESULTS: A substantive theory was generated to describe the psychological process experienced by breast cancer patients in their initial treatment. The core category was "rising from the ashes." Four categories emerged and represented 4 stages of the psychological process experienced by breast cancer patients. They were (1) fear stage: patients are frightened about permanent separation from family, chemotherapy, and the disease getting worse; (2) hardship stage: patients experience physical suffering and mental torment; (3) adjustment stage: patients fight against the disease, find methods for adjustment, and get assistance from supporting systems; (4) relaxation stage: patients were released from both the physical and mental sufferings, and patients accepted the disease-related change in their lives. CONCLUSION: Each stage is closely related to the other stages, and each is likely to occur repeatedly. It is important to help patients achieve the relaxation stage. IMPLICATIONS FOR PRACTICE: The results of this study may enhance nurses' understanding of the psychological process of patients receiving initial chemotherapy for breast cancer, thereby helping nurses to provide appropriate assistance to improve the quality of patient care.


Assuntos
Adaptação Psicológica , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/psicologia , Adulto , Medo/psicologia , Feminino , Teoria Fundamentada , Humanos , Pessoa de Meia-Idade , Teoria Psicológica , Pesquisa Qualitativa , Estresse Psicológico/psicologia , Taiwan
6.
Chemistry ; 21(5): 1878-81, 2015 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-25469917

RESUMO

An organic-inorganic hybrid zinc phosphate with 28-ring channels was synthesized by use of an organic ligand instead of organic amine template under a hydro(solvo)thermal condition. This crystalline zinc phosphate contains large channels constructed from 28 zinc and phosphate tetrahedral units. The walls of the channels consist of two types of zincophosphate chains, in which the Zn atoms are coordinated by 2,4,5-tri(4-pyridyl)-imidazole ligands as pendent groups. This compound exhibits yellow emission and interesting properties of removing cobalt, cadmium, and mercury cations from aqueous solution. A new two-dimensional organic-inorganic hybrid zincophosphate was also obtained by changing the solvent mixture ratios in the synthesis.

7.
Cancer Genet Cytogenet ; 201(2): 94-101, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20682393

RESUMO

The objective of this study was to investigate whether somatic mutations in the mitochondrial DNA (mtDNA) D-loop region correlate with known prognostic factors, namely, age, tumor size, lymph node status, metastasis, tumor-node-metastasis stage, lymphovascular invasion, and status of the progesterone receptor, estrogen receptor, ERBB2 (alias HER2/neu), and TP53 proteins (as determined by immunohistochemistry) and to investigate their relationship, if any, to TP53 mutations in human breast cancer. Thirty breast tumors without BRCA mutation, along with adjacent nontumorous tissues, were genotyped for the mtDNA D-loop region and for the promoter as well as the coding region of the TP53 gene. Clinicopathological parameters were recorded and assessed. In all, 17 somatic mtDNA D-loop mutations were identified, in 13 of 30 tumor samples (43%); two mutations were novel: 544C>T and 16510A>C. Four TP53 mutations were found in six tumor samples (20%), and two (c.437G>A and c.706T>C) were novel. Only progesterone receptor status correlated with the number of somatic mtDNA D-loop mutations (likelihood chi-square test; P < 0.05). Somatic mutations in the mtDNA D-loop and in TP53 were independent of each other (Fisher's exact test; P > 0.05). These results suggest that the number of somatic mtDNA D-loop mutations may be an indicator of poor prognosis through a mechanism independent of TP53.


Assuntos
Neoplasias da Mama/genética , Análise Mutacional de DNA/métodos , DNA Mitocondrial/genética , Proteína Supressora de Tumor p53/genética , Distribuição de Qui-Quadrado , Metilação de DNA , DNA Mitocondrial/metabolismo , Feminino , Humanos , Pessoa de Meia-Idade , Mutação , Prognóstico , Análise de Sobrevida , Proteína Supressora de Tumor p53/metabolismo
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