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1.
Zhonghua Yan Ke Za Zhi ; 60(7): 592-600, 2024 Jul 11.
Artigo em Zh | MEDLINE | ID: mdl-38955761

RESUMO

Objective: To explore the characteristics of refractive parameters and retinal and choroidal blood flow in dominant and non-dominant eyes. Methods: A cross-sectional study. Students who were 18 to 32 years old and had emmetropia or myopia but no systemic diseases were recruited from universities in Wuhu, Anhui Province from April 2019 to August 2023. They were divided into 4 groups based on the difference in spherical equivalent between two eyes:<0.50 D (group A), 0.50 to 1.74 D (group B), 1.75 to 2.49 D (group C), and≥2.50 D (group D). The card hole method was used to determine the dominant eye. The refractive parameters of both eyes were recorded, including spherical equivalent, myopia degree, astigmatism degree, axial length, and corneal curvature difference (K2-K1). Optical coherence tomography angiography was performed to measure the blood flow density of the superficial retinal capillaries, deep retinal capillaries (DVC), avascular layer (AC), entire retina, choroidal capillaries, and choroidal vessels, as well as the retina and choroid as a whole. Statistical analysis was conducted using the paired sample t-test, chi square test, and variance analysis. Results: A total of 78 eligible subjects, aged (24.50±2.36) years old, 28 males and 50 females, were included. Fifty subjects had the right eye and 28 had the left eye as the dominant eye. Forty-two subjects had high myopia in the dominant eye, and 30 had high myopia in the non-dominant eye. There were statistically significant differences (all P<0.05) in the spherical equivalent [(-4.588±2.534) D vs. (-4.058±2.453) D], myopic spherical power [(-4.253±2.504) D vs. (-3.779±2.425) D], and axial length [(25.531±1.212) mm vs. (25.256±1.238) mm] between dominant and non-dominant eyes among all subjects, as well as in the astigmatism degree of groups A and C, spherical power of groups B to D, and spherical power and axial length of groups C and D. There were also statistically significant differences (all P<0.05) in the blood flow density of the DVC [(0.291±0.130) vs. (0.257±0.148)], AC [(0.347±0.118) vs. (0.326±0.126)], and overall retina and choroid [(0.385±0.102) vs. (0.349±0.084)] between dominant and non-dominant eyes among all subjects, as well as in the blood flow density of the superficial retinal capillaries, DVC, AC, choroidal capillaries, and overall retina and choroid of groups C and D, density of the choroidal vessels of group C, and density of the entire retina of group D. Conclusions: In young individuals with emmetropia or near vision, the degree of myopia in dominant eyes is higher than that in non-dominant eyes. When the difference in the spherical equivalent between two eyes is ≥1.75 D, the blood flow density of the retina and choroid in the dominant eye is greater than that in the non-dominant eye.


Assuntos
Corioide , Miopia , Refração Ocular , Humanos , Masculino , Feminino , Estudos Transversais , Adulto , Adulto Jovem , Miopia/fisiopatologia , Corioide/irrigação sanguínea , Adolescente , Retina , Vasos Retinianos , Astigmatismo , Fluxo Sanguíneo Regional
2.
Biometrics ; 78(2): 474-486, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-33630311

RESUMO

Motivated by an analysis of single molecular experiments in the study of T-cell signaling, a new model called varying coefficient frailty model with local linear estimation is proposed. Frailty models have been extensively studied, but extensions to nonconstant coefficients are limited to spline-based methods that tend to produce estimation bias near the boundary. To address this problem, we introduce a local polynomial kernel smoothing technique with a modified expectation-maximization algorithm to estimate the unknown parameters. Theoretical properties of the estimators, including their unbiased property near the boundary, are derived along with discussions on the asymptotic bias-variance trade-off. The finite sample performance is examined by simulation studies, and comparisons with existing spline-based approaches are conducted to show the potential advantages of the proposed approach. The proposed method is implemented for the analysis of T-cell signaling. The fitted varying coefficient model provides a rigorous quantification of an early and rapid impact on T-cell signaling from the accumulation of bond lifetime, which can shed new light on the fundamental understanding of how T cells initiate immune responses.


Assuntos
Fragilidade , Modelos Estatísticos , Algoritmos , Simulação por Computador , Humanos , Projetos de Pesquisa
3.
Zhonghua Fu Chan Ke Za Zhi ; 56(3): 161-170, 2021 Mar 25.
Artigo em Zh | MEDLINE | ID: mdl-33874710

RESUMO

Objective: To explore the effects of interpregnancy interval (IPI) on pregnancy outcomes of subsequent pregnancy. Methods: A multicenter retrospective study was conducted in 21 hospitals in China. Information of age, height, pre-pregnancy weight, IPI, history of diseases, complications of pregnancy, gestational age of delivery, delivery mode, and pregnancy outcomes of the participants were collected by consulting medical records of pregnant women who had two consecutive deliveries in the same hospital during 2011 to 2018. The participants were divided into 4 groups according to IPI:<18 months, 18-23 months, 24-59 months and ≥60 months. According to the WHO's recommendation, with the IPI of 24-59 months group as a reference, to the effects of IPI on pregnancy outcomes of subsequent pregnancy were analyzed. Stratified analysis was further carried out based on age, history of gestational diabetes mellitus (GDM), macrosomia, and premature delivery, to explore the differences in the effects of IPI on pregnancy outcomes among women with different characteristics. Results: A total of 8 026 women were included in this study. There were 423, 623, 5 512 and 1 468 participants in <18 months group, 18-23 months group, 24-59 months group and ≥60 months group, respectively. (1) The age, pre-pregnancy body mass index (BMI), history of cesarean section, GDM, gestational hypertension and cesarean section delivery rate of <18 months group, 18-23 months group, 24-59 months group and ≥60 months group were gradually increased, and the differences were statistically significant (P<0.05). (2) After adjusting for potential confounding factors, compared with women in the IPI of 24-59 months group, the risk of premature delivery, premature rupture of membranes, and oligohydramnios were increased by 42% (OR=1.42, 95%CI: 1.07-1.88, P=0.015), 46% (OR=1.46, 95%CI: 1.13-1.88, P=0.004), and 64% (OR=1.64, 95%CI: 1.13-2.38, P=0.009) respectively for women in the IPI≥60 months group. No effects of IPI on other pregnancy outcomes were found in this study (P>0.05). (3) After stratified by age and adjusted for confounding factors, compared with women in the IPI of 24-59 months group, IPI≥60 months would significantly increase the risk of oligohydramnios for women with advanced age (OR=2.87, 95%CI: 1.41-5.83, P=0.004); and <18 months could increase the risk of premature rupture of membranes for women under the age of 35 (OR=1.59, 95%CI: 1.04-2.43, P=0.032). Both the risk of premature rupture of membranes (OR=1.58, 95%CI: 1.18-2.13, P=0.002) and premature delivery (OR=1.52, 95%CI: 1.07-2.17, P=0.020) were significantly increased in the IPI≥60 months group. After stratified by history of GDM and adjusted for confounding factors, compared with women in the IPI of 24-59 months group, IPI≥60 months would lead to an increased risk of postpartum hemorrhage for women with a history of GDM (OR=5.34, 95%CI: 1.45-19.70, P=0.012) and an increased risk of premature rupture of membranes for women without a history of GDM (OR=1.44, 95%CI: 1.10-1.90, P=0.009). After stratified by history of macrosomia and adjusted for confounding factors, compared with women in the IPI of 24-59 months group, IPI≥60 months could increase the proportion of cesarean section for women with a history of macrosomia (OR=4.11, 95%CI: 1.18-14.27, P=0.026) and the risk of premature rupture of membranes for women without a history of macrosomia (OR=1.46, 95%CI: 1.12-1.89, P=0.005). After stratified by history of premature delivery and adjusted for confounding factors, compared with women in the IPI of 24-59 months group, IPI≥60 months would significantly increase the risk of premature rupture of membranes for women without a history of premature delivery (OR=1.47, 95%CI: 1.13-1.92, P=0.004). Conclusions: Both IPI≥60 months and <18 months would increase the risk of adverse pregnancy outcomes in the subsequent pregnancy. Healthcare education and consultation should be conducted for women of reproductive age to maintain an appropriate IPI when they plan to pregnant again, to reduce the risk of adverse pregnancy outcomes in the subsequent pregnancy.


Assuntos
Diabetes Gestacional , Nascimento Prematuro , Intervalo entre Nascimentos , Cesárea , China/epidemiologia , Diabetes Gestacional/epidemiologia , Feminino , Humanos , Lactente , Gravidez , Resultado da Gravidez/epidemiologia , Nascimento Prematuro/epidemiologia , Estudos Retrospectivos
4.
Mol Biol (Mosk) ; 54(2): 252-261, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32392194

RESUMO

PARP10 is an intracellular mono-ADP ribosyltransferase and recent reports suggest that it regulates proliferation of some cell types. However, its effect on the proliferation of colorectal carcinoma cells has not yet been systematically reported. We explored the influence of PARP10 on the proliferation of several colorectal carcinoma cell types and carried out initial studies on the underlying mechanisms. Inhibition of the enzymatic activity of PARP10 led to significantly decreases in proliferative ability in LoVo cells and CT26 cells in vitro and suppressed growth of CT26 tumours in the subaxilliary region in Balb/c mice in vivo. Cell-cycle arrest accompanied these observations. Expression of the nuclear transfer factor ß-catenin and it trans-location to the nucleus were also affected and the expression of its associated signal proteins Axin2 and c-Myb were increased and decreased, respectively. We demonstrate that PARP10 promotes proliferation of those colorectal carcinoma cells which express significant levels of PARP10. This promotion is suppressed when the enzymatic activity is inhibited. ß-Catenin is likely to be the mediator of the antiproliferative effect.


Assuntos
Proliferação de Células , Neoplasias Colorretais/patologia , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Animais , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Humanos , Camundongos , Camundongos Endogâmicos BALB C , beta Catenina/metabolismo
5.
Cryo Letters ; 39(1): 39-44, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29734413

RESUMO

  The survival of porcine oocytes is still very low after cryopreservation. OBJECTIVE: To investigate whether and when the mitochondrial function of vitrified porcine oocytes could be recovered post-thaw. MATERIALS AND METHODS: Mitochondrial potential, ROS level, ATP content, apoptotic rate, caspase activity, and parthenogenetics developmental ability of thawed porcine oocytes were measured after culture in vitro for 0, 1, 2 or 4 h. RESULTS: Mitochondrial potential after 2 h and 4 h post-thaw culture were 1.19 and 1.26, significantly lower than that of fresh oocytes but much higher than the groups cultured for 0 h and 1 h (P<0.05). Cryopreservation increased the ROS level in oocytes considerably, which decreased only after 2 to 4 h incubation following thaw. ATP content increased gradually over time and recovered to the level comparable to that of fresh oocytes after 4 h. Pan caspase levels increased after cryopreservation and reached the highest level at 1 h incubation. Thereafter it decreased to a low value, but still higher than fresh oocytes. Oocytes showing an early apoptotic event decreased upon 2 to 4 h incubation. The parthenogenetic cleavage and blastocyst rates were the highest (19.8% and 5.6%) after 2 h incubation. CONCLUSION: The recovery of mitochondrial function could complete after 2 to 4 h post-thaw incubation. Post-thaw incubation for 2 to 4 h reduced apoptotic events and improved parthenogenetic developmental ability of vitrified porcine MII stage oocytes.


Assuntos
Congelamento , Metáfase , Mitocôndrias/metabolismo , Oócitos/fisiologia , Vitrificação , Trifosfato de Adenosina/metabolismo , Animais , Apoptose , Sobrevivência Celular , Criopreservação , Feminino , Espaço Intracelular/metabolismo , Potencial da Membrana Mitocondrial , Espécies Reativas de Oxigênio/metabolismo , Sus scrofa
6.
Diabet Med ; 33(1): 39-46, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25970380

RESUMO

AIMS: To evaluate the relationship between gestational diabetes (GDM) and incidence of cancer in women within the first decade postpartum. METHODS: This population-based retrospective cohort study compared the risk of cancer in women with GDM with that of a matched control group comprising pregnant women without diabetes. We included women from Ontario, Canada aged 20-50 years with no history of cancer who had given birth between 1995 and 2008 (N = 149 049). Women with GDM (N = 49 684) were matched on age and year of giving birth, in a ratio of 1:2, to pregnant women without diabetes (N = 99 365). RESULTS: Over a median 8-year follow-up, there were a total of 2927 (1.5%) cancers. After adjustment for covariates, we found no significant difference in overall risk of cancer between women with GDM and matched control subjects; however, GDM was associated with a significantly greater risk of thyroid cancer (adjusted hazard ratio 1.24, 95% CI 1.05, 1.46) and a significantly lower risk of premenopausal breast cancer (hazard ratio 0.86, 95% CI 0.75, 0.98) compared with matched control subjects. CONCLUSIONS: This large population-based study did not find a greater risk of cancers among women with GDM during the first decade postpartum; however, GDM was associated with a higher risk of thyroid cancer and a lower risk of premenopausal breast cancer. Further studies are needed to confirm these findings.


Assuntos
Diabetes Gestacional/fisiopatologia , Período Pós-Parto , Gravidez em Diabéticas/fisiopatologia , Pré-Menopausa , Neoplasias da Glândula Tireoide/etiologia , Adulto , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/etiologia , Estudos de Coortes , Feminino , Seguimentos , Humanos , Incidência , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Ontário/epidemiologia , Gravidez , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Neoplasias da Glândula Tireoide/epidemiologia , Cobertura Universal do Seguro de Saúde , Adulto Jovem
7.
Cryo Letters ; 37(2): 129-36, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27224525

RESUMO

BACKGROUND: Oocytes vitrification is widely used for cryopreservation of female genetic resources. OBJECTIVE: In order to illuminate the apoptotic pathways of porcine MII stage oocytes after vitrification. MATERIALS AND METHODS: This study used in situ fluorescence staining and RT-PCR to detect the expression levels of some key molecules from death receptor and mitochondria mediated apoptotic pathways. RESULTS: (1) Early stage apoptosis were detected in both PI staining survival oocytes and PI staining dead oocytes. (2) The fluorescence intensity of caspase 8, caspase 9, caspase 3 and pan caspase from vitrified oocytes were 32.03, 16.56, 16.70 and 8.43 respectively, which were much higher than those from fresh oocytes (4.02, 4.83, 4.23 and 3.08, P < 0.05). (3) Not only the genes from death receptor mediated apoptotic pathway, but also from mitochondrial mediated apoptotic pathway were changed greatly. CONCLUSION: The death of porcine vitrified oocytes could be induced by apoptosis, both death receptor and mitochondria mediated apoptotic pathways participated the occurrence of apoptosis in porcine vitrified MII stage oocytes.


Assuntos
Apoptose , Criopreservação/veterinária , Oócitos , Sus scrofa/fisiologia , Vitrificação , Animais , Criopreservação/métodos , Feminino , Hibridização in Situ Fluorescente/veterinária , Mitocôndrias/metabolismo , Reação em Cadeia da Polimerase/veterinária , Receptores de Morte Celular/genética , Receptores de Morte Celular/metabolismo
8.
Chaos ; 25(10): 103113, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26520079

RESUMO

Rogue waves are unexpectedly large and localized displacements from an equilibrium position or an otherwise calm background. For the nonlinear Schrödinger (NLS) model widely used in fluid mechanics and optics, these waves can occur only when dispersion and nonlinearity are of the same sign, a regime of modulation instability. For coupled NLS equations, rogue waves will arise even if dispersion and nonlinearity are of opposite signs in each component as new regimes of modulation instability will appear in the coupled system. The same phenomenon will be demonstrated here for a coupled "AB" system, a wave-current interaction model describing baroclinic instability processes in geophysical flows. Indeed, the onset of modulation instability correlates precisely with the existence criterion for rogue waves for this system. Transitions from "elevation" rogue waves to "depression" rogue waves are elucidated analytically. The dispersion relation as a polynomial of the fourth order may possess double pairs of complex roots, leading to multiple configurations of rogue waves for a given set of input parameters. For special parameter regimes, the dispersion relation reduces to a cubic polynomial, allowing the existence criterion for rogue waves to be computed explicitly. Numerical tests correlating modulation instability and evolution of rogue waves were conducted.

9.
Genet Mol Res ; 14(4): 13860-7, 2015 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-26535701

RESUMO

The aim of this study was to examine the expression of macrophage migration-inhibitory factor (MIF) in duodenal ulcer epithelial cells and its relation to Helicobacter pylori (Hp) infection, and to discuss the pathogenic roles of MIF expression and Hp infection in duodenal ulcer. MIF protein and mRNA expression was examined in samples from patients with duodenal ulcer with and without Hp infection (N = 40 each, experimental group), and in normal duodenal bulb mucosal tissue (N = 40, control group) using immunohistochemistry and in situ hybridization. Patients without Hp infection received routine treatment, and treatment was provided to the patients positive for Hp to eradicate Hp infection. Hp and MIF expression levels before treatment and after the ulcer had been cured were compared. The positive rates of MIF protein and mRNA in patients with Hp infection before treatment were 67.5 and 65%, respectively, and were 18.9 and 21.6% in the 37 patients from whom Hp was eliminated. These were statistically different both before and after treatment compared with controls (P < 0.05). In the patients without Hp infection, the positive rates of MIF protein and mRNA expression before (45 and 47.5%, respectively) and after (32.5 and 30%) treatment were not significantly different (P > 0.05). The results of this study suggested that MIF is related to the development of duodenal ulcer, and that the presence of Hp is closely related with the expression of MIF in the duodenal mucosa and the development of duodenal ulcer.


Assuntos
Úlcera Duodenal/etiologia , Úlcera Duodenal/metabolismo , Infecções por Helicobacter/complicações , Infecções por Helicobacter/microbiologia , Helicobacter pylori , Fatores Inibidores da Migração de Macrófagos/metabolismo , Adulto , Idoso , Biópsia , Úlcera Duodenal/diagnóstico , Feminino , Expressão Gênica , Infecções por Helicobacter/tratamento farmacológico , Humanos , Imuno-Histoquímica , Hibridização In Situ , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Fatores Inibidores da Migração de Macrófagos/genética , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Adulto Jovem
10.
Int J Cancer ; 134(6): 1346-58, 2014 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-24154944

RESUMO

The chemokine receptor CXCR2 and its ligands CXCL1, CXCL2 and CXCL5 play an important role in homing of tumor-associated neutrophils (TANs) into developing tumors. TANs are known to support the development of blood vessels in growing solid tumors, hence contributing to tumor growth. Here, we show that the migration of neutrophils is influenced by endogenous interferon-beta (IFN-ß) via regulation of such chemokines and their receptor. We could demonstrate that CXCL1 and CXCL2 gradients are formed in tumor-bearing mice, i.e., low chemokine level in bone marrow (BM) and high level in the tumor. This supports migration of neutrophils into the tumor. Moreover, expression of CXCR2 was highest on neutrophils from BM and lowest in TANs. Importantly, although IFN-ß appears to have only a minor influence on the expression of CXCR2, it strongly regulates the CXCR2 ligands. In the absence of endogenous IFN-ß, they were expressed significantly higher in tumor-infiltrating neutrophils. Treatment of such neutrophils from tumor-bearing Ifnb1(-/-) mice with recombinant IFN-ß downregulated CXCR2 ligand expression to wild-type levels. This explains the reduced migration of neutrophils into tumors and the diminished tumor angiogenesis in IFN-ß-sufficient mice. Our results add a novel functional aspect of the type I IFN system as effector molecules of natural cancer surveillance and open interesting possibilities for antineutrophil therapies against cancer.


Assuntos
Fibrossarcoma/patologia , Interferon beta/fisiologia , Melanoma Experimental/patologia , Infiltração de Neutrófilos/imunologia , Neutrófilos/imunologia , Receptores de Interleucina-8B/metabolismo , Sarcoma Experimental/patologia , Animais , Medula Óssea/imunologia , Medula Óssea/metabolismo , Medula Óssea/patologia , Movimento Celular , Quimiocina CXCL1/genética , Quimiocina CXCL1/metabolismo , Quimiocina CXCL2/genética , Quimiocina CXCL2/metabolismo , Quimiocina CXCL5/genética , Quimiocina CXCL5/metabolismo , Feminino , Fibrossarcoma/imunologia , Fibrossarcoma/metabolismo , Citometria de Fluxo , Técnicas Imunoenzimáticas , Melanoma Experimental/imunologia , Melanoma Experimental/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neutrófilos/metabolismo , Neutrófilos/patologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptores de Interleucina-8B/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sarcoma Experimental/imunologia , Sarcoma Experimental/metabolismo
11.
Br J Cancer ; 110(2): 341-52, 2014 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-24300974

RESUMO

BACKGROUND: Gambogic acid (GA) has been reported to have potent anticancer activity and is authorised to be tested in phase II clinical trials for treatment of non-small-cell lung cancer (NSCLC). The present study aims to investigate whether GA would be synergistic with cisplatin (CDDP) against the NSCLC. METHODS: 1-(4,5-Dimethylthiazol-2-yl)-3,5-diphenylformazan (MTT), combination index (CI) isobologram, western blot, quantitative PCR, flow cytometry, electrophoretic mobility shift assay, xenograft tumour models and terminal deoxynucleotide transferase-mediated dUTP nick-end labelling analysis were used in this study. RESULTS: The cell viability results showed that sequential CDDP-GA treatment resulted in a strong synergistic action in A549, NCI-H460, and NCI-H1299 cell lines, whereas the reverse sequence and simultaneous treatments led to a slight synergistic or additive action. Increased sub-G1 phase cells and enhanced PARP cleavage demonstrated that the sequence of CDDP-GA treatment markedly increased apoptosis in comparison with other treatments. Furthermore, the sequential combination could enhance the activation of caspase-3, -8, and 9, increase the expression of Fas and Bax, and decrease the expression of Bcl-2, survivin and X-inhibitor of apoptosis protein (X-IAP) in A549 and NCI-H460 cell lines. In addition, increased apoptosis was correlated with enhanced reactive oxygen species generation. Importantly, it was found that, followed by CDDP treatment, GA could inhibit NF-κB and mitogen-activated protein kinase (MAPK)/heme oxygenase-1 (HO-1) signalling pathways, which have been validated to reduce ROS release and confer CDDP resistance. The roles of NF-κB and MAPK pathways were further confirmed by using specific inhibitors, which significantly increased ROS release and apoptosis induced by the sequential combination of CDDP and GA. Moreover, our results indicated that the combination of CDDP and GA exerted increased antitumour effects on A549 xenograft models through inhibiting NF-κB, HO-1, and subsequently inducing apoptosis. CONCLUSION: Gambogic acid sensitises lung cancer cells to CDDP in vitro and in vivo in NSCLC through inactivation of NF-κB and MAPK/HO-1 signalling pathways, providing a rationale for the combined use of CDDP and GA in lung cancer chemotherapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Cisplatino/farmacologia , Heme Oxigenase-1/antagonistas & inibidores , Neoplasias Pulmonares/tratamento farmacológico , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , NF-kappa B/antagonistas & inibidores , Xantonas/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Carcinoma Pulmonar de Células não Pequenas/enzimologia , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Caspases/genética , Caspases/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Cisplatino/administração & dosagem , Regulação para Baixo/efeitos dos fármacos , Sinergismo Farmacológico , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Humanos , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Xantonas/administração & dosagem
12.
Diabet Med ; 31(11): 1410-7, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24863747

RESUMO

AIMS: To assess the combined impact of socio-economic status and gender on the risk of diabetes-related lower extremity amputation within a universal healthcare system. METHODS: We conducted a population-based cohort study using administrative health databases from Ontario, Canada. Adults with pre-existing or newly diagnosed diabetes (N = 606 494) were included and the incidence of lower extremity amputation was assessed for the period 1 April 2002 to 31 March 2009. Socio-economic status was based on neighbourhood-level income groups, assigned to individuals using the Canadian Census and their postal code of residence. RESULTS: Low socio-economic status was associated with a significantly higher incidence of lower extremity amputation (27.0 vs 19.3 per 10,000 person-years in the lowest (Q1) vs the highest (Q5) socio-economic status quintile. This relationship persisted after adjusting for primary care use, region of residence and comorbidity, and was greater among men (adjusted Q1:Q5 hazard ratio 1.41, 95% CI 1.30-1.54; P < 0.0001 for all male gender-socio-economic status interactions) than women (hazard ratio 1.20, 95% CI 1.06-1.36). Overall, the incidence of lower extremity amputation was higher among men than women (hazard ratio for men vs women: 1.87, 95% CI 1.79-1.96), with the greatest disparity between men in the lowest socio-economic status category and women in the highest (hazard ratio 2.39, 95% CI 2.06-2.77 and hazard ratio 2.30, 95% CI 1.97-2.68, for major and minor amputation, respectively). CONCLUSIONS: Despite universal access to hospital and physician care, we found marked socio-economic status and gender disparities in the risk of lower extremity amputation among patients with diabetes. Men living in low-income neighbourhoods were at greatest risk.


Assuntos
Amputação Cirúrgica , Pé Diabético/cirurgia , Adulto , Amputação Cirúrgica/economia , Estudos de Coortes , Pé Diabético/economia , Pé Diabético/epidemiologia , Pé Diabético/fisiopatologia , Feminino , Seguimentos , Disparidades nos Níveis de Saúde , Humanos , Incidência , Cobertura do Seguro , Reembolso de Seguro de Saúde , Masculino , Ontário/epidemiologia , Áreas de Pobreza , Modelos de Riscos Proporcionais , Sistema de Registros , Fatores de Risco , Índice de Gravidade de Doença , Fatores Sexuais , Medicina Estatal
13.
Nutr Metab Cardiovasc Dis ; 24(3): 236-42, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24361071

RESUMO

BACKGROUND AND AIMS: Abdominal aortic calcification (AC) has been reported to be associated with cardiovascular disease (CVD) in hemodialysis patients but is rarely discussed in peritoneal dialysis (PD) patients. We examined the independent predictors and predictive power for survival of AC in prevalent PD patients. METHODS AND RESULTS: AC was detected by computed tomography (CT) and represented as the percentage of the total aortic cross-section area affected by AC (%AC). The predictors of %AC ≥ 15 were examined by multiple logistic regression analysis. Cox proportional hazard analysis was used to determine the hazard ratios associated with high %AC. A total of 183 PD patients were recruited to receive CT scans and divided into group 1 (%AC < 15, n = 97), group 2 (%AC ≥ 15, n = 41), and group 3 (diabetic patients, n = 45). Group 1 patients had lower osteoprotegerin (OPG) levels than group 2 patients (798 ± 378 vs. 1308 ± 1350 pg/mL, p < 0.05). The independent predictors for %AC ≥ 15 included the atherogenic index, OPG, and C-reactive protein (CRP). The age-adjusted hazard ratios associated with %AC ≥ 15 were 3.46 (p = 0.043) for mortality and 1.90 (p = 0.007) for hospitalization. CONCLUSIONS: %AC can predict mortality and morbidity in non-diabetic PD patients, and 15% is a good cut-off value for such predictions. There are complex associations among mineral metabolism, inflammation, and dyslipidemia in the pathogenesis of AC.


Assuntos
Aorta Abdominal/fisiopatologia , Calcinose/epidemiologia , Dislipidemias/epidemiologia , Inflamação/epidemiologia , Osteoprotegerina/sangue , Diálise Peritoneal/efeitos adversos , Adulto , Idoso , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Doenças Cardiovasculares/epidemiologia , Estudos Transversais , Diabetes Mellitus , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Taiwan , Tomografia Computadorizada por Raios X
14.
Opt Express ; 20(8): 8485-95, 2012 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-22513556

RESUMO

We propose an asymmetric quantum well structure to realize strong interaction between two slow optical pulses. The essential idea is the combination of the advantages of inverted-Y type scheme and resonant tunneling. We analytically demonstrate that giant cross-Kerr nonlinearity can be achieved with vanishing absorptions. Owing to resonant tunneling, the contributions of the probe and signal cross-Kerr nonlinearities to total nonlinear phase shift vary from destructive to constrictive, leading to nonlinear phase shift on order of π at low light level. In this structure, the scheme is inherent symmetric for the probe and signal pulses. Consequently, the condition of group velocity matching can be fulfilled with appropriate initial electron distribution.

15.
Eur J Vasc Endovasc Surg ; 44(1): 82-7, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22531452

RESUMO

OBJECTIVE: To identify the risk factors for catheter migration and demonstrate possible mechanisms of this migration. DESIGN: Retrospective study. SETTING: Chang Gung Memorial Hospital, a tertiary medical centre in Taiwan. PATIENTS: Patients who underwent implantation of intravenous ports via the superior vena cava (SVC). INTERVENTIONS: Procedures involving catheter placement and re-intervention for catheter migration. MAIN OUTCOME MEASURES: The anatomic location of the catheter tip was confirmed by plain chest X-rays (postero-anterior view). From these plain radiographs, the distance (in cm) between the carina and catheter tip and the angle (in degrees) between the locking nut and catheter were measured. METHODS: A total of 1542 procedures related to intravenous port implantation were retrospectively reviewed but only procedures involving implantation via the SVC were included in the analysis. The study group was composed of 31 interventions because of catheter migration, while the control group consisted of 1475 implantation and re-intervention procedures except those involving catheter migrations. RESULTS: Shallow catheter-tip location (p < 0.0001) and the presence of lung cancer (p = 0.006) were risk factors for catheter migration. CONCLUSIONS: Shallow catheter-tip location and the presence of lung cancer are risk factors for catheter migration. Strategies that ensure low catheter-tip location and avoid increased thoracic pressure may be useful preventive measures.


Assuntos
Implante de Prótese Vascular/métodos , Cateterismo Venoso Central/efeitos adversos , Migração de Corpo Estranho/etiologia , Átrios do Coração , Medição de Risco , Veia Cava Superior , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Implante de Prótese Vascular/efeitos adversos , Cateterismo Venoso Central/instrumentação , Criança , Falha de Equipamento , Feminino , Migração de Corpo Estranho/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Taiwan/epidemiologia , Adulto Jovem
16.
Proc Natl Acad Sci U S A ; 106(29): 11845-50, 2009 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-19556542

RESUMO

Quantifying the mechanical properties of nanomaterials is challenged by its small size, difficulty of manipulation, lack of reliable measurement techniques, and grossly varying measurement conditions and environment. A recently proposed approach is to estimate the elastic modulus from a force-deflection physical model based on the continuous bridged-deformation of a nanobelt/nanowire using an atomic force microscope tip under different contact forces. However, the nanobelt may have some initial bending, surface roughness and imperfect physical boundary conditions during measurement, leading to large systematic errors and uncertainty in data quantification. In this article, a statistical modeling technique, sequential profile adjustment by regression (SPAR), is proposed to account for and eliminate the various experimental errors and artifacts. SPAR can automatically detect and remove the systematic errors and therefore gives more precise estimation of the elastic modulus. This research presents an innovative approach that can potentially have a broad impact in quantitative nanomechanics and nanoelectronics.

17.
Indian J Biochem Biophys ; 48(3): 141-7, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21793303

RESUMO

This is the first report of three different fusion proteins with an antitumor-analgesic peptide obtained from Chinese scorpion Buthus martensii Karsch (BmKAGAP). The fusion proteins were constructed in the form of chimeric toxins, aiming to obtain bifunctional analgesic and antitumor activity. The fusion proteins consisted of luteinizing hormone-releasing hormone (LHRH), three different types of flexible linkers (L1, Ser-Ser-His-His-His-His-His-His-Ser-Ser-Gly-Leu-Val-Pro-Arg-Gly-Ser-His-Met; L2, Gly-Gly-Gly-Ser-Gly-Gly-Gly-Ser; L3, Ser-Gly-Gly-Ser-Gly-Gly-Ser-Gly-Gly-Gly-Ser-Ser-Gly-Gly-Ser-Gly-Gly-Gly-Gly-Ser-Gly-Gly-Gly-Gly-Ser), and BmKAGAP. The genes coding three fusion proteins were cloned and expressed in E. coli in soluble form. Following two successive column chromatographic separations, purified fusion proteins were obtained. These fusion proteins exhibited analgesic activity in mice and were cytotoxic to a hepatocellular carcinoma cell line Hep3B.


Assuntos
Analgésicos/isolamento & purificação , Analgésicos/farmacologia , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Venenos de Escorpião/biossíntese , Venenos de Escorpião/farmacologia , Analgésicos/administração & dosagem , Analgésicos/química , Animais , Antineoplásicos/química , Antineoplásicos/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Escherichia coli/genética , Escherichia coli/metabolismo , Humanos , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Camundongos , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/farmacologia , Venenos de Escorpião/administração & dosagem , Venenos de Escorpião/química , Venenos de Escorpião/isolamento & purificação , Escorpiões
18.
Br J Cancer ; 103(6): 852-60, 2010 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-20736946

RESUMO

BACKGROUND: Parvin-beta (ParvB), a potential tumour suppressor gene, is a focal adhesion protein. We evaluated the role of ParvB in the upper urinary tract urothelial cell carcinoma (UUT-UC). METHODS: ParvB mRNA and proteins levels in UUT-UC tissue were investigated by quantitative real-time polymerase chain reaction and western blot analysis, respectively. In addition, the expression of ParvB in tissues from patients with UUT-UC at different stages was evaluated by immunohistochemistry. Furthermore, biological functions of ParvB in urothelial cancer cells were investigated using a doxycycline-inducible overexpression system and siRNA. RESULTS: Western blot and mRNA analysis showed downregulation of ParvB expression in frozen UUT-UC tissue. Immunohistochemistry revealed high staining intensity of ParvB in normal urothelium, which decreased markedly at advanced stages of UUT-UC (P=0.0000). Moreover, ParvB was an independent prognostic indicator for disease-specific survival of patients with UUT-UC. Functional assays indicated that overexpression of ParvB in an urothelial cancer cell line resulted in decreased cell growth rate and ability to migrate. In contrast, knockdown of ParvB expression increased cell migration ability. CONCLUSIONS: Downregulation of ParvB expression significantly increased urothelial cancer cell growth and migration. Downexpression of ParvB level in UUT-UC correlated with tumour stage, and was an independent unfavourable prognostic factor for disease-specific survival of patients with UUT-UC.


Assuntos
Actinina/metabolismo , Biomarcadores Tumorais/metabolismo , Neoplasias da Bexiga Urinária/metabolismo , Urotélio/patologia , Actinina/química , Actinina/genética , Sequência de Bases , Western Blotting , Divisão Celular/fisiologia , Movimento Celular/fisiologia , Primers do DNA , Técnicas de Silenciamento de Genes , Humanos , Imuno-Histoquímica , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sobrevida , Neoplasias da Bexiga Urinária/patologia
19.
J Sports Med Phys Fitness ; 50(1): 32-6, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20308969

RESUMO

AIM: This study evaluated the reliability and validity of a proposed 10 min running speed variance test (RSVHRC) in assessing aerobic power at which the intensity was controlled at 80% of age-predicted maximal heart rate (HR). METHODS: Forty-four college students (21 men and 23 women, age: 21+/-3 years, height: 166.6+/-7.9 cm, weight: 61.7+/-9.3 kg) were recruited to undergo 2 RSVHRC test trials, and a maximal exercise test at least 24 hours apart. The test consisted of a 3-min warm-up at 1.67 km/h, followed by adjusting speed up to either at 2.5 m/s or 2.78 m/s immediately depending upon onset HR after the warm-up. HR was monitored every 30 seconds and running speed was adjusted accordingly to maintain HR (+/-5bpm) for 10 minutes. RSVHRC was determined by the slope of distance/time relationship from 3rd to 10th min. RESULTS: Pair t-test showed that there was no significant difference between 1st (2.38+/-0.58 m/s) and 2nd trial (2.40+/-0.63 m/s). Intraclass correlation coefficient (ICC) score showed that RSVHRC was highly reliable (ICC=0.98, 95% CI=0.97-0.99). Coefficient of variation, standard error of measurement (SEM), and %SEM were 4.8%, 0.12 m/s, 5.02% respectively. Additionally, a Pearson product-moment correlation coefficient demonstrated 2 trials were correlated with maximal oxygen uptake (46.6+/-8.1 mL/kg/min) at r=0.74, 0.71 (P<0.05). CONCLUSION: In conclusion, 80%HRmax RSVHRC is an easy and highly reliable submaximal exercise test that provides good validity to assess aerobic power in young and healthy population, which can be applied on treadmill setting.


Assuntos
Exercício Físico/fisiologia , Frequência Cardíaca/fisiologia , Aptidão Física/fisiologia , Corrida/fisiologia , Análise de Variância , Intervalos de Confiança , Teste de Esforço , Feminino , Humanos , Modelos Lineares , Masculino , Consumo de Oxigênio , Reprodutibilidade dos Testes , Estatística como Assunto , Adulto Jovem
20.
Zhonghua Liu Xing Bing Xue Za Zhi ; 41(2): 249-260, 2020 Feb 10.
Artigo em Zh | MEDLINE | ID: mdl-32164138

RESUMO

Objective: To evaluate the relative safety of different ventilation methods regarding mortality and rates of complication, on neonatal respiratory distress syndrome (NRDS). Methods: Network Meta-analysis was used to collect data on randomized controlled trials of pulmonary ventilation strategies in preterm infants with a mean gestational age of less than 32 weeks. Diagnostic criteria on NRDS were published in the PubMed, Cochrane, Web of Science, EBSCO, and Springer Link databases from January 1986 to June 2018. Revman 5.3 software was used to evaluate the quality of studies, based on the Cochrane quality assessment tool. Data were analyzed by Bayesian and frequency methods, using both Win BUGS 1.4.3 and STATA 13.0 software. Safety of different ventilation strategies for NRDS mortality and complications would include intraventricular hemorrhage (IVH), patent ductus arteriosus (PDA) and retinopathy of prematurity (ROP) and were evaluated. Counted data was displayed by OR and 95%CI. Results: A total of 31 RCTs were included in this paper, including 5 827 preterm infants and 11 ventilation strategies. There were no statistically significant differences appearing in 11 ventilation strategies on mortality, PDA or ROP. IVH results were reported in 28 studies. Compared with nasal intermittent positive pressure ventilation (NIPPV), both high- frequency oscillation ventilation (HFOV) (OR=3.33, 95%CI: 1.08-16.67, P<0.05) and synchronized intermittent mechanical ventilation (SIMV) (OR=8.22, 95%CI: 1.25-29.44, P<0.05) schemes seemed to have increased the risk of IVH in preterm infants with NRDS. NIPPV appeared the optimal ventilation strategy in the rankings of cumulative probability. Results on clustering showed that NIPPV was probably the best ventilation strategy for children with NRDS after considering the orders of IVH, PDA and ROP on mortality, respectively. However, HFOV, IMV, and SIMV did not seem to be the ideal ventilated strategies. Conclusions: Most of the clinical decision makers might prefer using NIPPV in the treatment of children with NRDS through mechanical ventilation systems to reduce both the incidence and death caused by IVH, PDA and ROP. It was not recommended to use HFOV, SIMV and IMV in treating NRDS with gestational less than 32 weeks. We suggested that larger numbers of multi-center RCTs ba carried out to make the above conclusions more convincing.


Assuntos
Respiração Artificial/efeitos adversos , Respiração Artificial/métodos , Síndrome do Desconforto Respiratório do Recém-Nascido/terapia , Teorema de Bayes , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Ventilação com Pressão Positiva Intermitente/efeitos adversos , Ventilação com Pressão Positiva Intermitente/métodos , Metanálise em Rede , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
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