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1.
Ultrasound Obstet Gynecol ; 62(5): 660-667, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37289938

RESUMO

OBJECTIVES: To assess whether coexisting fetal growth restriction (FGR) influences pregnancy latency among women with preterm pre-eclampsia undergoing expectant management. Secondary outcomes assessed were indication for delivery, mode of delivery and rate of serious adverse maternal and perinatal outcomes. METHODS: We conducted a secondary analysis of the Pre-eclampsia Intervention (PIE) and the Pre-eclampsia Intervention 2 (PI2) trial data. These randomized controlled trials evaluated whether esomeprazole and metformin could prolong gestation of women diagnosed with pre-eclampsia between 26 and 32 weeks of gestation undergoing expectant management. Delivery indications were deteriorating maternal or fetal status, or reaching 34 weeks' gestation. FGR (defined by Delphi consensus) at the time of pre-eclampsia diagnosis was examined as a predictor of outcome. Only placebo data from PI2 were included, as the trial showed that metformin use was associated with prolonged gestation. All outcome data were collected prospectively from diagnosis of pre-eclampsia to 6 weeks after the expected due date. RESULTS: Of the 202 women included, 92 (45.5%) had FGR at the time of pre-eclampsia diagnosis. Median pregnancy latency was 6.8 days in the FGR group and 15.3 days in the control group (difference 8.5 days; adjusted 0.49-fold change (95% CI, 0.33-0.74); P < 0.001). FGR pregnancies were less likely to reach 34 weeks' gestation (12.0% vs 30.9%; adjusted relative risk (aRR), 0.44 (95% CI, 0.23-0.83)) and more likely to be delivered for suspected fetal compromise (64.1% vs 36.4%; aRR, 1.84 (95% CI, 1.36-2.47)). More women with FGR underwent a prelabor emergency Cesarean section (66.3% vs 43.6%; aRR, 1.56 (95% CI, 1.20-2.03)) and were less likely to have a successful induction of labor (4.3% vs 14.5%; aRR, 0.32 (95% CI, 0.10-1.00)), compared to those without FGR. The rate of maternal complications did not differ significantly between the two groups. FGR was associated with a higher rate of infant death (14.1% vs 4.5%; aRR, 3.26 (95% CI, 1.08-9.81)) and need for intubation and mechanical ventilation (15.2% vs 5.5%; aRR, 2.97 (95% CI, 1.11-7.90)). CONCLUSION: FGR is commonly present in women with early preterm pre-eclampsia and outcome is poorer. FGR is associated with shorter pregnancy latency, more emergency Cesarean deliveries, fewer successful inductions and increased rates of neonatal morbidity and mortality. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Metformina , Pré-Eclâmpsia , Recém-Nascido , Lactente , Gravidez , Feminino , Humanos , Resultado da Gravidez , Cesárea/efeitos adversos , Pré-Eclâmpsia/diagnóstico , Retardo do Crescimento Fetal/etiologia , Conduta Expectante , Metformina/uso terapêutico
2.
Eur J Obstet Gynecol Reprod Biol ; 258: 198-207, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33450711

RESUMO

An accurate prognostic method for preterm birth (PTB) could avoid unnecessary treatment(s) with potentially negative effects. The objective was to explore the prognostic accuracy of commercially available bedside cervicovaginal biomarker tests in combination with cervical length (CL) compared to CL measurement alone and/or a biomarker test alone, for PTB within 7 days after testing symptomatic women at 22-34 weeks. The MEDLINE, Cochrane, Embase and Web of Science databases were searched from inception to August 28th, 2019. Seven hundred and eight articles were identified and screened using Rayyan. Studies reporting on the predictive accuracy of combined tests compared to CL or biomarker alone for the prediction of PTB within 7 days of testing in symptomatic women with intact membranes were included. A piloted data extraction form was used. Direct comparisons of the prognostic accuracy of the combination test with CL measurement or a biomarker alone were done, as well as comparisons of prognostic accuracy of the included combination tests (indirect comparisons). Twelve articles were included (seven on fetal fibronectin, four on phosphorylated insulin-like growth factor binding protein-1, one comparing both). A variety of CL cut-offs was reported. The results could not demonstrate superiority of a combination method compared to single methods. Due to data scarcity and quality, the superiority of either predictive test for PTB, either combination or single, cannot be demonstrated with this systematic review. We recommend further research to compare available biomarkers.


Assuntos
Trabalho de Parto Prematuro , Nascimento Prematuro , Biomarcadores , Medida do Comprimento Cervical , Colo do Útero/diagnóstico por imagem , Feminino , Fibronectinas , Humanos , Recém-Nascido , Valor Preditivo dos Testes , Gravidez , Nascimento Prematuro/diagnóstico
3.
BJOG ; 126(13): 1588-1597, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31529591

RESUMO

OBJECTIVE: To examine the association of prenatal alcohol exposure (PAE) on cognitive abilities and behaviour profiles of 4-year-old children. DESIGN: Prospective cohort study. SETTING: Cape Town, South Africa. POPULATION: A cohort of 500 children. METHODS: Children from the Safe Passage Study, which prospectively collected PAE, were included. Cognition and behavioural profiles were assessed. Children with and without PAE were compared. Mean scores were compared, with P ≤ 0.05 considered significant. Results were adjusted for confounding factors. MAIN OUTCOME MEASURES: The Kaufman Assessment Battery for children measured intellectual and mental ability; the NEPSY-II instrument assessed neurocognitive performance. The caregiver completed the Preschool Child Behaviour checklist to rate the child's problem behaviours and competencies. RESULTS: Two hundred children had no PAE, 117 children had mild to moderate PAE (with no binge episodes), 113 children had heavy PAE (with one or two binge episodes), and 70 children had very heavy PAE (with three or more binge episodes). Women who binge drank had significantly higher rates of smoking, marijuana use, and methamphetamine use. Low to moderate PAE had no effect on cognitive ability and behaviour. Very heavy PAE was associated with problems performing simultaneous as well as sequential functions, lower scores in the language and sensorimotor domain, and more attention and pervasive developmental problems. CONCLUSIONS: Low to moderate PAE was not associated with cognitive processing or developmental problems. Women who had many binge drinking episodes during pregnancy were the most at risk for cognitive processing, neurocognitive, and behaviour problems in their children at 4 years of age. TWEETABLE ABSTRACT: Low to moderate prenatal alcohol use was not associated with cognitive or behavioural problems in 4-year-olds.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Desenvolvimento Infantil/fisiologia , Transtornos do Neurodesenvolvimento/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Pré-Escolar , Feminino , Seguimentos , Inquéritos Epidemiológicos , Humanos , Masculino , Transtornos do Neurodesenvolvimento/epidemiologia , Testes Neuropsicológicos , Gravidez , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Estudos Prospectivos , África do Sul/epidemiologia
4.
PLoS One ; 12(1): e0168977, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28081195

RESUMO

BACKGROUND: The aim of this study was to assess the feasibility and reproducibility of semi-automatic volumetric measurement of retroperitoneal lymph node metastases in testicular cancer (TC) patients treated with chemotherapy versus the standardized manual measurements based on RECIST criteria. METHODS: 21 TC patients with retroperitoneal lymph node metastases of testicular cancer were studied with a CT scan of chest and abdomen before and after cisplatin based chemotherapy. Three readers, a surgical resident, a radiological technician and a radiologist, assessed tumor response independently using computerized volumetric analysis with Vitrea software® and manual measurement according to RECIST criteria (version 1.1). Intra- and inter-rater variability were evaluated with intra class correlations and Bland-Altman analysis. RESULTS: Assessment of intra observer and inter observer variance proved non-significant in both measurement modalities. In particularly all intraclass correlation (ICC) values for the volumetric analysis were > .99 per observer and between observers. There was minimal bias in agreement for manual as well as volumetric analysis. CONCLUSION: In this study volumetric measurement using Vitrea software® appears to be a reliable, reproducible method to measure initial tumor volume of retroperitoneal lymph node metastases of testicular cancer after chemotherapy. Both measurement methods can be performed by experienced non-radiologists as well.


Assuntos
Tomografia Computadorizada de Feixe Cônico/métodos , Processamento de Imagem Assistida por Computador/métodos , Neoplasias Retroperitoneais/diagnóstico por imagem , Neoplasias Retroperitoneais/secundário , Software , Neoplasias Testiculares/diagnóstico por imagem , Adulto , Idoso , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador
5.
Nonlinear Dyn ; 87(1): 169-190, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-32669757

RESUMO

The new generations of compact high output power-to-weight ratio internal combustion engines generate broadband torsional oscillations, transmitted to lightly damped drivetrain systems. A novel approach to mitigate these untoward vibrations can be the use of nonlinear absorbers. These act as Nonlinear Energy Sinks (NESs). The NES is coupled to the primary (drivetrain) structure, inducing passive irreversible targeted energy transfer (TET) from the drivetrain system to the NES. During this process, the vibration energy is directed from the lower-frequency modes of the structure to the higher ones. Thereafter, vibrations can be either dissipated through structural damping or consumed by the NES. This paper uses a lumped parameter model of an automotive driveline to simulate the effect of TET and the assumed modal energy redistribution. Significant redistribution of vibratory energy is observed through TET. Furthermore, the integrated optimization process highlights the most effective configuration and parametric evaluation for use of NES.

6.
Horm Metab Res ; 48(12): 834-839, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27813049

RESUMO

The aim of this study was to map the genetic expression of the vitamin D metabolizing enzymes CYP27A, CYP27B1, CYP2R1, and CYP24A1 in the first trimester in different human fetal tissues. In addition, the gene expression was correlated with fetal age, season, and presence of single nucleotide polymorphisms (SNPs) in the genes encoding CYP27A1 (rs4674344), CYP2R1 (rs2060793), and CYP24A1 (rs6013897). Fetal samples from livers (n=60), kidneys (n=43), lungs (n=37), and intestines (n=14) were analyzed by quantitative PCR. In addition, the expression of the enzymes was also analyzed in adult livers (n=20). The highest expression of CYP2R1 and CYP24A1 was found in fetal kidney and lung. CYP27A1 was expressed at the highest levels in the liver and kidney and CYP27B1 had the highest levels in the kidney. The expression of fetal hepatic CYP2R1 and CYP27A1 was increased during summertime. Carriers of the G-allele of the rs2060793 SNP in the CYP2R1 gene, a genotype previously associated with rickets, had lower levels of CYP2R1 mRNA.In conclusion, this study suggest that the kidneys rather than the liver, may be of importance for fetal vitamin D metabolism, even for the 25-hydroxylation, during the first trimester. The results also suggest that the lungs and intestines are important for vitamin D metabolism in the fetus. Finally, GG- carriers of the rs2060793 SNP had significantly lower CYP2R1 expression and might be at risk for 25-hydroxyvitamin D deficiency.


Assuntos
Feto/enzimologia , Perfilação da Expressão Gênica , Primeiro Trimestre da Gravidez/genética , Vitamina D/metabolismo , Adolescente , Adulto , Idoso , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Feminino , Regulação Enzimológica da Expressão Gênica , Frequência do Gene/genética , Genótipo , Idade Gestacional , Humanos , Hidroxilação , Fígado/embriologia , Fígado/enzimologia , Masculino , Pessoa de Meia-Idade , Especificidade de Órgãos/genética , Polimorfismo de Nucleotídeo Único/genética , Gravidez , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Estações do Ano , Adulto Jovem
7.
Phys Rev E ; 94(3-1): 032214, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27739799

RESUMO

We study the dynamics and acoustics of a nonlinear lattice with fixed boundary conditions composed of a finite number of particles coupled by linear springs, undergoing in-plane oscillations. The source of the strongly nonlinearity of this lattice is geometric effects generated by the in-plane stretching of the coupling linear springs. It has been shown that in the limit of low energy the lattice gives rise to a strongly nonlinear acoustic vacuum, which is a medium with zero speed of sound as defined in classical acoustics. The acoustic vacuum possesses strongly nonlocal coupling effects and an orthogonal set of nonlinear standing waves [or nonlinear normal modes (NNMs)] with mode shapes identical to those of the corresponding linear lattice; in contrast to the linear case, however, all NNMs except the one with the highest wavelength are unstable. In addition, the lattice supports two types of waves, namely, nearly linear sound waves (termed "L waves") corresponding to predominantly axial oscillations of the particles and strongly nonlinear localized propagating pulses (termed "NL pulses") corresponding to predominantly transverse oscillating wave packets of the particles with localized envelopes. We show the existence of nonlinear nonreciprocity phenomena in the dynamics and acoustics of the lattice. Two opposite cases are examined in the limit of low energy. The first gives rise to nonreciprocal dynamics and corresponds to collective, spatially extended transverse loading of the lattice leading to the excitation of individual, predominantly transverse NNMs, whereas the second case gives rise to nonreciprocal acoutics by considering the response of the lattice to spatially localized, transverse impulse or displacement excitations. We demonstrate intense and recurring energy exchanges between a directly excited NNM and other NNMs with higher wave numbers, so that nonreciprocal energy exchanges from small-to-large wave numbers are established. Moreover, we show the existence of nonreciprocal wave interaction phenomena in the form of irreversible targeted energy transfers from L waves to NL pulses during collisions of these two types of waves. Additional nonreciprocal acoustics are found in the form of complex "cascading processes, as well as nonreciprocal interactions between L waves and stationary discrete breathers. The computational studies confirm the theoretically predicted transition of the lattice dynamics to a low-energy state of nonlinear acoustic vacum with strong nonlocality.

8.
J Environ Radioact ; 162-163: 379-387, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27359098

RESUMO

Concern from northern communities following the Fukushima Daiichi nuclear accident of March 2011 has prompted a reassessment of the safety of their traditional foods with respect to radioactivity levels. To this end, a study was conducted to measure the levels of radionuclides in Arctic caribou (Rangifer tarandus) and beluga (Delphinapterus leucas). The main radionuclide of concern is cesium-137, which is easily transferred through the lichen-caribou food chain. Previous studies have been conducted on the cesium-137 levels in Canadian caribou herds from 1958 to 2000, allowing researchers to determine the amount of cesium-137 in caribou specifically attributable to atmospheric weapons testing and the Chernobyl nuclear accident in 1986. In this study, samples of lichens, mushrooms, caribou, beluga and beluga prey collected before and after the Fukushima accident were analyzed for radioactivity levels. Samples were processed and measured using gamma ray spectroscopy to identify the radionuclides present and determine the radioactivity concentration. Both calibration standards and Monte Carlo simulations were used to determine the efficiency of the detectors for the samples, taking into account differences in individual sample sizes as well as matrices. In particular, a careful analysis of the atomic composition of lichens and mushrooms was performed to ensure the efficiencies for these sample types were correct. A comparison of the concentrations from before and after the accident indicated that there was no increase in radioactivity as a result of the atmospheric plume from the Fukushima accident. Some cesium-137, likely attributable to fallout from atmospheric weapons testing of the 1950s and 1960s (since there was no cesium-134 measured in the samples), was measured in the post Fukushima caribou and beluga whale samples; however, this amount was determined to be insignificant for any radiological concern (9.1 ± 1.8 and 0.63 ± 0.23 Bq kg-1 ww respectively). The activity concentrations of cesium-137 was about 200 times smaller than that of natural radioactive potassium in the beluga samples. Both the caribou and beluga results showed that these foods continue to be a healthy food choice for northern Canadians with respect to radioactivity, and this result has been communicated to the nearby northern communities and stakeholders.


Assuntos
Beluga , Césio/análise , Acidente Nuclear de Fukushima , Monitoramento de Radiação , Rena , Animais , Radioisótopos de Césio/análise
9.
Phys Rev E ; 93(3): 032216, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27078353

RESUMO

We describe and explore accelerating oscillatory fronts in sonic vacua with nonlocal interactions. As an example, a chain of particles oscillating in the plane and coupled by linear springs, with fixed ends, is considered. When one end of this system is harmonically excited in the transverse direction, one observes accelerated propagation of the excitation front, accompanied by an almost monochromatic oscillatory tail. Position of the front obeys the scaling law l(t) ∼ t(4/3). The frequency of the oscillatory tail remains constant, and the wavelength scales as λ ∼ t(1/3). These scaling laws result from the nonlocal effects; we derive them analytically (including the scaling coefficients) from a continuum approximation. Moreover, a certain threshold excitation amplitude is required in order to initiate the front propagation. The initiation threshold is evaluated on the basis of a simplified discrete model, further reduced to a completely integrable nonlinear system. Given their simplicity, nonlinear sonic vacua of the type considered herein should be common in periodic lattices.

10.
Nanoscale ; 7(42): 17889-901, 2015 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-26462719

RESUMO

Targeting nanoparticles to desired intracellular compartments is a major challenge. Integrin-type adhesion receptors are connected to different endocytosis routes in a receptor-specific manner. According to our previous observations, the internalization of an α2ß1-integrin-echovirus-1 complex takes place via a macropinocytosis-like mechanism, suggesting that the receptor could be used to target nanoparticles to this specific entry route. Here, silica-based nanoparticles, carrying monoclonal antibodies against the α2ß1 integrin as address labels, were synthesized. Studies with flow cytometry, atomic force microscopy and confocal microscopy showed the particles to attach to the cell surface via the α2ß1 integrin. Furthermore, quantitative analysis of nanoparticle trafficking inside the cell performed with the BioImageXD software indicated that the particles enter cells via a macropinocytosis-like process and end up in caveolin-1 positive structures. Thus, we suggest that different integrins can guide particles to distinct endocytosis routes and, subsequently, also to specific intracellular compartments. In addition, we show that with the BioImageXD software it is possible to conduct sensitive and complex analyses of the behavior of small fluorescent particles inside cells, using basic confocal microscopy images.


Assuntos
Integrina alfa2beta1/química , Nanopartículas/química , Anticorpos Imobilizados/química , Anticorpos Imobilizados/metabolismo , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Caveolina 1/metabolismo , Linhagem Celular Tumoral , Endocitose , Enterovirus Humano B/genética , Enterovirus Humano B/metabolismo , Humanos , Imuno-Histoquímica , Integrina alfa2beta1/imunologia , Integrina alfa2beta1/metabolismo , Microscopia de Força Atômica , Microscopia Confocal , Dióxido de Silício/química
11.
Chaos ; 25(5): 053109, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26026321

RESUMO

The low-energy dynamics of a two-dof system composed of a grounded linear oscillator coupled to a lightweight mass by means of a spring with both cubic nonlinear and negative linear components is investigated. The mechanisms leading to intense energy exchanges between the linear oscillator, excited by a low-energy impulse, and the nonlinear attachment are addressed. For lightly damped systems, it is shown that two main mechanisms arise: Aperiodic alternating in-well and cross-well oscillations of the nonlinear attachment, and secondary nonlinear beats occurring once the dynamics evolves solely in-well. The description of the former dissipative phenomenon is provided in a two-dimensional projection of the phase space, where transitions between in-well and cross-well oscillations are associated with sequences of crossings across a pseudo-separatrix. Whereas the second mechanism is described in terms of secondary limiting phase trajectories of the nonlinear attachment under certain resonance conditions. The analytical treatment of the two aformentioned low-energy transfer mechanisms relies on the reduction of the nonlinear dynamics and consequent analysis of the reduced dynamics by asymptotic techniques. Direct numerical simulations fully validate our analytical predictions.

12.
World J Urol ; 32(4): 1015-9, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24096433

RESUMO

PURPOSE: To evaluate the value of chest X-ray in the follow-up of surgically treated T1-3N0M0 renal cell carcinoma. METHODS: We performed retrospective analysis of patients that underwent surgical treatment of a localized renal cell carcinoma (T1-3N0M0) between January 1993 and July 2010. Data on frequency and results of performed chest X-rays were collected from patients' records. RESULTS: In 17.5 years, 249 patients with a T1-3N0M0 renal cell carcinoma underwent a radical or partial nephrectomy. In 221 patients, 823 chest X-rays were performed during a median follow-up of 3.3 years (range 0.5-17 years). In 19 patients, a pulmonary recurrence occurred, of which 10 were not detected by the regular follow-up. Of the 9 patients that were diagnosed with a pulmonary recurrence with a chest X-ray during follow-up, 7 were asymptomatic at the time of diagnosis, and the chest X-ray has led to the detection; 0.85 % of the performed chest X-rays (7/823) have led to the detection of asymptomatic lung metastases. CONCLUSIONS: Due to the low yield of chest X-ray for detection of asymptomatic pulmonary recurrences, it has very low clinical value in the follow-up after nephrectomy for T1-3N0M0 renal cell carcinoma.


Assuntos
Carcinoma de Células Renais/diagnóstico , Carcinoma de Células Renais/secundário , Neoplasias Renais/cirurgia , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/secundário , Radiografia Torácica , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Renais/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Incidência , Neoplasias Renais/patologia , Neoplasias Pulmonares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Metástase Neoplásica/diagnóstico , Metástase Neoplásica/diagnóstico por imagem , Estadiamento de Neoplasias , Nefrectomia , Exame Físico , Estudos Retrospectivos , Sensibilidade e Especificidade
13.
Chaos ; 22(1): 013118, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22462994

RESUMO

We show that nonlinear inertial coupling between a linear oscillator and an eccentric rotator can lead to very interesting interchanges between regular and chaotic dynamical behavior. Indeed, we show that this model demonstrates rather unusual behavior from the viewpoint of nonlinear dynamics. Specifically, at a discrete set of values of the total energy, the Hamiltonian system exhibits non-conventional nonlinear normal modes, whose shape is determined by phase locking of rotatory and oscillatory motions of the rotator at integer ratios of characteristic frequencies. Considering the weakly damped system, resonance capture of the dynamics into the vicinity of these modes brings about regular motion of the system. For energy levels far from these discrete values, the motion of the system is chaotic. Thus, the succession of resonance captures and escapes by a discrete set of the normal modes causes a sequence of transitions between regular and chaotic behavior, provided that the damping is sufficiently small. We begin from the Hamiltonian system and present a series of Poincaré sections manifesting the complex structure of the phase space of the considered system with inertial nonlinear coupling. Then an approximate analytical description is presented for the non-conventional nonlinear normal modes. We confirm the analytical results by numerical simulation and demonstrate the alternate transitions between regular and chaotic dynamics mentioned above. The origin of the chaotic behavior is also discussed.


Assuntos
Algoritmos , Retroalimentação , Dinâmica não Linear , Oscilometria/métodos , Simulação por Computador
14.
Nanotechnology ; 22(42): 425706, 2011 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-21941034

RESUMO

The effects of Mg concentration and annealing temperature on the characteristics of nanocrystalline Mg(x)Zn(1 - x)O thin films (where x = 0-0.4) were studied using electron microscopy and photoluminescence. The films were prepared by a sol-gel method. The solid solubility limit of MgO in ZnO for the sol-gel-derived Mg(x)Zn(1 - x)O films in the present study was determined to be ∼ 20 at.%. Microstructural characterization of the films showed that the wurtzite crystallites decrease in size with increase in Mg concentration up to the solubility limit. Increasing Mg concentration beyond the solubility limit resulted in a decrease in crystallinity of the films. The bandgap energy was found to increase with Mg concentration whereas the linewidth first increased and then decreased when the Mg concentration was increased beyond the solubility limit. Photoluminescence properties have been correlated to the microstructure of the films. A growth mechanism for Mg(x)Zn(1 - x)O nanocrystalline films under the present processing conditions has also been proposed.

15.
Oncogene ; 30(11): 1272-80, 2011 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-21057548

RESUMO

CtBPs form NADH-sensitive chromatin-modifying complexes, which link cellular metabolism to gene transcription. They also function in the cytoplasm to regulate Golgi fissioning; their inhibition can consequently cause a Golgi-dependent checkpoint in G(2). We have recently identified a novel role of CtBPs in the maintenance of mitotic fidelity; inhibition of CtBP synthesis resulting in reduced association of aurora B with mitotic chromatin and aberrant segregation of chromosomes. Here, we demonstrate that it is the interaction of CtBPs with transcriptional regulators and/or chromatin-modifying enzymes in the cell nucleus, rather than their role in Golgi fission, which is critical for the maintenance of mitotic fidelity.


Assuntos
Oxirredutases do Álcool/metabolismo , Núcleo Celular/metabolismo , Proteínas de Ligação a DNA/metabolismo , Mitose , Proteínas do Tecido Nervoso/metabolismo , Oxirredutases do Álcool/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Núcleo Celular/genética , Proteínas Correpressoras , Proteínas de Ligação a DNA/genética , Feminino , Humanos , Proteínas do Tecido Nervoso/genética
16.
Poult Sci ; 89(11): 2370-9, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20952699

RESUMO

Attenuated Salmonella Enteriditis (ΔSE) recombinant vaccine vectors incorporating a Salmonella flagellar filament protein (fliC) subunit, a putative cell-mediated epitope, for expression of the lamB gene (encoding a maltose outer membrane porin), with or without co-expression of a putative immune-enhancing CD154 oligopeptide, were developed and compared with wild-type Salmonella Enteriditis (experiments 1 and 2) or the attenuated ΔSE empty vector (experiment 3) as initial vaccine candidates against Salmonella infection. A total of 3 experiments were performed to assess the infection and clearance rate of each of these constructs. Each construct or Salmonella Enteriditis was orally administered to broiler chicks at day of hatch by oral gavage (~10(8) cfu/chick). In experiments 1 to 3, liver-spleen and cecal tonsils were removed aseptically for recovery of wild-type Salmonella Enteriditis or ΔSE mutants. These experiments suggested that cell surface expression of fliC alone markedly increased the clearance rate of the vector at or before 21d postvaccination in all 3 experiments. In a fourth experiment, broilers were vaccinated with one of the vaccine constructs or the ΔSE empty vector and then challenged with wild-type Salmonella Typhimurium. At 19 d posthatch, 16 d postinfection, neither candidate protected against challenge significantly better than the ΔSE empty vector, although there was significantly less Salmonella recovered from vaccinated chickens as compared with nonvaccinated controls. These experiments indicate that these experimental vaccines did not protect against heterologous challenge or enhance clearance after Salmonella Typhimurium challenge; as such, their value as vaccines is limited. The increased clearance of the candidate vaccines, particularly the vector expressing fliC alone, may have value in that the fliC epitope may decrease the clearance time of other recombinant vectored Salmonella vaccines.


Assuntos
Salmonelose Animal/imunologia , Vacinas contra Salmonella/genética , Animais , Enterite/epidemiologia , Enterite/veterinária , Vetores Genéticos , Hipersensibilidade Tardia/imunologia , Hipersensibilidade Tardia/veterinária , Proteínas Recombinantes/imunologia , Salmonella/imunologia , Salmonella/isolamento & purificação , Salmonelose Animal/epidemiologia , Salmonella typhimurium/imunologia , Salmonella typhimurium/isolamento & purificação , Estados Unidos/epidemiologia
17.
Br J Ophthalmol ; 93(11): 1524-8, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19628487

RESUMO

AIM: To study time trends in the incidence of conjunctival melanoma in Sweden. METHODS: All patients with conjunctival melanoma from 1960 to 2005 in Sweden were identified through the Swedish Cancer Registry, cross-checked against hospital files, and validated by histopathological review (97.5%) or detailed hospital records (2.5%). The crude and age-standardised incidences were estimated separately for each sex and the annual change in incidence over time was estimated using a regression model with logarithmic incidence numbers. Time trends for the largest diameter, thickness and location of the tumour when diagnosed were analysed. RESULTS: The age-standardised incidence of conjunctival melanoma increased significantly in men (n = 89) from 0.10 cases/million to 0.74 cases/million (p = 0.001) and in women (n = 81) from 0.06 cases/million to 0.45 cases/million (p = 0.007). The annual relative change in age-standardised incidence was 16.9% (95% confidence interval (CI) 12.2 to 21.6) in men and 19.5% (95% CI 9.3 to 29.7) in women. The age-specific incidence was higher in men and women > or = 65 years (1.48 and 1.39 cases/million, respectively) than in younger men and women (0.3 and 0.2 cases/million, respectively). During the period of study, tumours became smaller (p = 0.005) and thinner (p = 0.002) at the time of diagnosis and increasingly arose from parts of the conjunctiva exposed to ultraviolet radiation (p = 0.001). CONCLUSION: The incidence of conjunctival melanoma increased in Sweden during the period 1960 to 2005.


Assuntos
Neoplasias da Túnica Conjuntiva/epidemiologia , Melanoma/epidemiologia , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Distribuição por Sexo , Suécia/epidemiologia , Fatores de Tempo , Adulto Jovem
18.
Radiat Prot Dosimetry ; 131(3): 385-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18640998

RESUMO

Radon has been identified as the second leading cause of lung cancer after tobacco smoking. Information on indoor radon concentrations is required to assess the lung cancer burden due to radon exposure. However, radon data in highly populated southern Ontario are very limited. Since radon in soil is believed to be the main source of radon in homes, measurements of soil gas radon concentrations can be used to estimate variations in radon potential of indoor environments. This study reports a transect survey of natural background variation in soil radon levels across southern Ontario. The results indicate that radon risk could be high in some areas of southern Ontario.


Assuntos
Poluentes Radioativos do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Radônio/análise , Poluentes Radioativos do Solo/análise , Radiação de Fundo , Canadá , Humanos
19.
J Epidemiol Community Health ; 62(8): 722-7, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18621958

RESUMO

BACKGROUND: An inverse association of IQ with mortality has been observed in previous studies. Analyses of associations between offspring's IQ and parental mortality in biological and non-biological family relations may shed light on genetic and environmental influences. METHODS: In a target cohort of 1,235,375 Swedish men, 931,825 (75%) men had complete data on all variables used. IQ of offspring was measured at age 18 and mothers and father were followed, on average, for 21.2 years and 19.7 years, respectively, with respect to all-cause and cause-specific mortality (cardiovascular disease, coronary heart disease, stroke and diabetes). The analyses were conducted by proportional hazards regression with adjustment for parental occupation, education and income. RESULTS: In adjusted analyses using IQ as a continuous variable over a standard nine-point scale, hazards ratio (HR) for all-cause mortality was 0.96 (95% CI 0.96 to 0.96) for fathers and 0.95 (0.95 to 0.95) for mothers. The corresponding HRs were 0.99 (0.97 to 1.00) for step-fathers and 0.97 (0.95 to 0.99) for step-mothers. In adjusted analyses, HRs for CVD mortality among fathers and mothers were 0.97 (0.96 to 0.97) and 0.94 (0.93 to 0.94) respectively. The corresponding HRs for diabetes mortality were 0.91 (0.89 to 0.92) among fathers and 0.85 (0.83 to 0.87) among mothers. CONCLUSIONS: The associations found in non-biological family relationships suggest shared environmental influences and/or assortative mating. Stronger IQ-mortality associations in biological than non-biological relationships suggest genetic influences. Stronger inverse offspring IQ-parental mortality associations in mothers than in fathers might be due to environmental factors or epigenetic mechanisms.


Assuntos
Inteligência/genética , Mortalidade , Pais , Adolescente , Métodos Epidemiológicos , Pai/estatística & dados numéricos , Feminino , Humanos , Masculino , Mães/estatística & dados numéricos , Meio Social , Suécia/epidemiologia
20.
Indoor Air ; 18(4): 346-8, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18503537

RESUMO

UNLABELLED: With the announcement of the Government of Canada's Radon Guideline and increased public awareness of radon risk, more and more Canadians wish to test their homes for radon. Radon service providers available on the Internet have attracted many homeowners' attention. These services provide an easy and less expensive way for homeowners to test radon levels in their homes. However, a question has frequently been asked, 'How reliable are the radon testing services available on the Internet?' To answer this question, we ordered 36 radon testing kits from 10 service providers on the Internet. The test results showed that online radon testing services could collectively meet the performance requirement. However, the quality of a few service providers needs to be improved. PRACTICAL IMPLICATIONS: Indoor radon tests were performed with detectors ordered from 10 service providers available on the Internet. The results showed that online radon testing services could collectively meet the performance requirement. However, the quality of a few service providers needs to be improved.


Assuntos
Comércio , Monitoramento Ambiental/instrumentação , Internet , Radônio/análise , Canadá , Monitoramento Ambiental/normas , Desenho de Equipamento , Habitação , Controle de Qualidade , Sensibilidade e Especificidade
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