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1.
Front Public Health ; 12: 1336188, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38504684

RESUMO

Background: Individual metal levels are potential risk factors for the development of preeclampsia (PE). However, understanding of relationship between multiple metals and PE remains elusive. Purpose: The purpose of this study was to explore whether eight metals [zinc (Zn), manganese (Mn), copper (Cu), nickel (Ni), lead (Pb), arsenic (As), cadmium (Cd), and mercury (Hg)] in serum had a certain relationship with PE. Methods: A study was conducted in Dongguan, China. The concentrations of metals in maternal serum were assessed using inductively coupled plasma mass spectrometry (ICP-MS). Data on various factors were collected through a face-to-face interview and hospital electronic medical records. The unconditional logistic regression model, principal component analysis (PCA) and Bayesian Kernel Machine Regression (BKMR) were applied in our study. Results: The logistic regression model revealed that the elevated levels of Cu, Pb, and Hg were associated with an increased risk of PE. According to PCA, principal component 1 (PC1) was predominated by Hg, Pb, Mn, Ni, Cu, and As, and PC1 was associated with an increased risk of PE, while PC2 was predominated by Cd and Zn. The results of BKMR indicated a significant positive cumulative effect of serum metals on PE risk, with Ni and Cu exhibiting a significant positive effect. Moreover, BKMR results also revealed the nonlinear effects of Ni and Cd. Conclusion: The investigation suggests a potential positive cumulative impact of serum metals on the occurrence of PE, with a particular emphasis on Cu as a potential risk factor for the onset and exacerbation of PE. These findings offer valuable insights for guiding future studies on this concern.


Assuntos
Arsênio , Mercúrio , Metais Pesados , Pré-Eclâmpsia , Feminino , Humanos , Metais Pesados/análise , Cádmio , Teorema de Bayes , Chumbo , Arsênio/análise , Zinco , Níquel , Manganês
2.
Front Pediatr ; 12: 1336108, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38318453

RESUMO

Background: During the special period of the global spread of COVID-19, pregnant women are sensitive groups to the impacts of COVID-19 epidemic. However, the effects of lockdown measures implemented in response to the COVID-19 on fetal birthweight remain unclear. Objectives: This study investigated the associations of COVID-19 lockdown with birth weight in Chinese population. Methods: We collected 730,153 data of participants from hospitals of five cities in the south of China, we defined the time period of level I response (1/23-2/24/2020) as level I lockdown, and women who were pregnant during level I lockdown as the exposure group. Women who were pregnant during the same calendar month from 2015 to 2019 were defined as the unexposed group. We quantitatively estimate the individual cumulative exposure dose by giving different weights to days with different emergency response levels. Generalized linear regression models were used to estimate the association between COVID-19 lockdown exposure with birth weight and risk of low birth weight (<2,500 g) and macrosomia (>4,000 g). Results: The birth weight of the exposed group is heavier than the unexposed group (3,238.52 vs. 3,224.11 g: adjusted ß = 24.39 g [95% CI: 21.88, 26.91 g]). The exposed group had a higher risk of macrosomia (2.8% vs. 2.6%; adjusted OR = 1.17 [95% CI: 1.12, 1.22]). More obvious associations were found between COVID-19 lockdown and macrosomia in women who experienced the lockdown in their early pregnancy. Women who experienced the lockdown at their 4-7 weeks of pregnancy showed statistically significant heavier birth weight than unexposed group (after adjustment): ß = 1.28 (95% CI: 1.11, 1.46) g. We also observed a positive association between cumulative exposure dose of COVID-19 lockdown in all pregnant women and birth weight, after divided into four groups, Q1: ß = 32.95 (95% CI: 28.16, 37.75) g; Q2: ß = 18.88 (95% CI: 14.12, 23.64) g; Q3: ß = 19.50 (95% CI: 14.73, 24.28) g; Q4: ß = 21.82 (95% CI: 17.08, 26.56) g. However, there was no statistically significant difference in the risk of low birth weight between exposed and unexposed groups. Conclusions: The COVID-19 lockdown measures were associated with a heavier birth weight and a higher risk of macrosomia. Early pregnancy periods may be a more susceptible exposure window for a heavier birth weight and a higher risk of macrosomia. We also observed a positive association between cumulative exposure dose of COVID-19 lockdown and birth weight. The government and health institutions should pay attention to the long-term health of the infants born during the COVID-19 lockdown period, and follow up these mothers and infants is necessary.

3.
Environ Toxicol ; 39(4): 2123-2137, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38108539

RESUMO

Patrinia scabiosaefolia Fisch (PS), a perennial herb belonging to the genus Pinus in the family Pinnacle Sauce, has been previously known for its analgesic, anti-inflammatory, antibacterial, and antitumor properties. However, the specific mechanism behind its antileukemic effect remains unknown. This study focused on the cytotoxicity and potential modes of action of the dichloromethane extract from PS (DEPS) in acute myeloid leukemia (AML) cells. Our results demonstrated that DEPS reduced cell viability, arrested the cell cycle in the G2/M phase, disrupted the mitochondrial membrane potential, increased reactive oxygen species (ROS) production, and upregulated the expression of Bax/Bcl-2 and Cleaved caspase-3. However, the impact of DEPS on cell viability and the expression of apoptosis-associated proteins was reversed upon pretreatment with the caspase-3 inhibitor (Z-DEVD-FMK) in HL-60 cells, which demonstrated that DEPS could induce apoptosis through the mitochondria-associated apoptotic pathway. Interestingly, DEPS also influenced autophagy by upregulating the expression of LC3II/I, P62, and Beclin-1 proteins, and the autophagy inhibition chloroquine(CQ) could attenuate the apoptotic effects of DEPS in HL-60 cells. Furthermore, SMART 2.0 analysis predicted that the main components present in DEPS were likely terpenoids. In conclusion, DEPS possibly exerts antileukemic effects by downregulating the PI3K/AKT and ERK pathways, thereby promoting intracellular ROS production, activating the mitochondrial apoptotic pathway, and affecting autophagy, providing valuable insights for the potential future application of PS in the treatment of AML.


Assuntos
Leucemia Mieloide Aguda , Patrinia , Humanos , Caspase 3/metabolismo , Linhagem Celular Tumoral , Patrinia/metabolismo , Cloreto de Metileno/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Fosfatidilinositol 3-Quinases , Apoptose , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/patologia , Autofagia
4.
J Adv Res ; 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37625570

RESUMO

INTRODUCTION: The health effects of ambient ozone have been investigated in many previous studies. However, the effects of long-term exposure to ambient ozone on the incidence of cardiovascular disease (CVD) remain inconclusive. OBJECTIVES: To estimate the associations of long-term exposure to maximum daily 8-hours average ozone (MDA8 O3) with the incidence of total CVD, heart disease, hypertension, and stroke. METHODS: This was a prospective cohort study, and the data was obtained from the China Health and Retirement Longitudinal Survey (CHARLS) implemented during 2011-2018 and the China Family Panel Studies (CFPS) implemented during 2010-2018. We applied a Cox proportional hazards regression model to evaluate the associations of MDA8 O3 with total CVD, heart disease, hypertension, and stroke risks, and the corresponding population-attributable fractions (PAF) attributable to MDA8 O3 were also calculated. All analyses were conducted by R software. RESULTS: The mean MDA8 O3 concertation of all included participants in the CHARLS and CFPS were 51.03 part per billion (ppb) and 51.15 ppb, respectively. In the CHARLS including 18,177 participants, each 10 ppb increment in MDA8 O3 concentration was associated with a 31% increase [hazard ratio (HR) = 1.31, 95% confidence interval (CI): 1.22-1.42] in the risk of incident heart disease, and the corresponding population-attributable fractions (PAF) was 13.79% [10.12%-17.32%]. In the CFPS including 30,226 participants, each 10 ppb increment in MDA8 O3 concentration was associated with an increase in the risk of incident total CVD (1.07 [1.02-1.13]), and hypertension (1.10 [1.03-1.18]). The PAFs of total CVD, and hypertension attributable to MDA8 O3 were 3.53% [0.82%-6.16%], and 5.11% [1.73%-8.38%], respectively. Stratified analyses showed greater associations in males, urban areas, and Southern China. CONCLUSIONS: Long-term exposure to MDA8 O3 may increase the incidence of CVD. Therefore, the policies that control O3 and related precursors are persistently needed.

5.
Phys Rev Lett ; 128(19): 195001, 2022 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-35622043

RESUMO

The new hohlraum experimental platform and the quasi-3D simulation model are developed to enable the study of the indirect drive experiment using the six-cylinder-port hohlraum for the first time. It is also the first implosion experiment for the six laser-entrance-hole hohlraum to effectively use all the laser beams of the laser facility that is primarily designed for the cylindrical hohlraum. The experiments performed at the 100 kJ Laser Facility produce a peak hohlraum radiation temperature of ∼222 eV for ∼80 kJ and 2 ns square laser pulse. The inferred x-ray conversion efficiency η∼87% is similar to the cylindrical hohlraum and higher than the octahedral spherical hohlraum at the same laser facility, while the low laser backscatter is similar to the outer cone of the cylindrical hohlraum. The hohlraum radiation temperature and M-band (>1.6 keV) flux can be well reproduced by the quasi-3D simulation. The variations of the yield-over-clean and the hot spot shape can also be semiquantitatively explained by the calculated major radiation asymmetry of the quasi-3D simulation. Our work demonstrates the capability for the study of the indirect drive with the six-cylinder-port hohlraum at the cylindrically configured laser facility, which is essential for numerically assessing the laser energy required by the ignition-scale six-cylinder-port hohlraum.

6.
Clin Chim Acta ; 531: 361-367, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35483441

RESUMO

BACKGROUND: Mercury (Hg) is a highly toxic substance, and its harmful effects on maternal and infant health have been reported. Yet, the associations of Hg exposure with preeclampsia (PE) and adverse birth outcomes are not well understood. OBJECTIVE: The aim of this study was to investigate the potential effects of maternal Hg exposure on PE and birth outcomes. METHODS: We conducted a case-control study with 84 participants in China. Logistic models were used to estimate odds ratios for PE risk and birth outcomes according to maternal blood Hg levels, adjusting for potential confounding factors. RESULTS: Elevated blood Hg levels were associated with increased risks of mild PE (aOR, 7.03; 95% CI, 1.61, 30.62; P < 0.01) and severe PE (aOR, 47.55; 95% CI, 5.27, 429.05; P < 0.05). We also found that increased blood Hg levels were associated with low birth weight (aOR, 1.12; 95% CI, 1.00, 1.25; P < 0.05) and preterm birth (PTB) (aOR, 1.22; 95% CI, 1.08, 1.38; P < 0.05). CONCLUSIONS: Our study provided evidence that elevated blood Hg levels were significantly associated with an increased risk of PE. In addition, our findings support that increased blood Hg levels might be associated with low birth weight and PTB.


Assuntos
Mercúrio , Pré-Eclâmpsia , Nascimento Prematuro , Estudos de Casos e Controles , Feminino , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Gravidez
7.
Front Endocrinol (Lausanne) ; 13: 824245, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35432191

RESUMO

Importance: The ongoing pandemic of COVID-19 is still affecting our life, but the effects of lockdown measures on gestational diabetes mellitus (GDM) in pregnant women remain unclear. Aim: To investigate the association between COVID-19 lockdown and GDM. Subjects and Methods: Medical records of 140844 pregnant women during 2015-2020 were extracted from 5 hospitals in Guangdong Province, China. Pregnant women who underwent the COVID-19 Level I lockdown (1/23 - 2/24/2020) during pregnancy were defined as the exposed group (N=20472) and pregnant women who underwent the same calendar months during 2015-2019 (1/23 - 2/24) were defined as the unexposed group (N=120372). Subgroup analyses were used to explore the potential susceptible exposure window of COVID-19 lockdown on GDM. Cumulative exposure is quantitatively estimated by assigning different weights to response periods with different exposure intensities. A logistic regression model was used to estimate the association between COVID-19 lockdown exposure and GDM. Results: The rates of GDM in the exposed and unexposed groups were 15.2% and 12.4%, respectively. The overall analyses showed positive associations (odds ratio, OR=1.22, 95%CI: 1.17, 1.27) between lockdown exposure and GDM risk in all pregnant women. More pronounced associations were found in women who underwent the COVID-19 lockdown in their first four months of pregnancy, and the adjusted OR values ranged from 1.24 (95%CI: 1.10, 1.39) in women with 5-8 gestational weeks (GWs) to 1.35 (95%CI: 1.20, 1.52) with < 5 GWs. In addition, we found a positive exposure-response association of cumulative lockdown exposure with the risk of GDM. Conclusions: The COVID-19 lockdown was associated with an increased risk of GDM, and the first four months of pregnancy may be the window for sensitive exposure.


Assuntos
COVID-19 , Diabetes Gestacional , COVID-19/epidemiologia , China/epidemiologia , Controle de Doenças Transmissíveis , Diabetes Gestacional/epidemiologia , Feminino , Humanos , Gravidez , Gestantes
8.
Biol Trace Elem Res ; 200(9): 3965-3974, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34993909

RESUMO

Preeclampsia (PE) is a pregnancy-specific disorder, which is one of the leading causes of maternal, fetal, and neonatal death, particularly in developing countries. Arsenic (As), which is commonly found in soil and groundwater, has been associated with various complications of pregnancy, such as spontaneous abortion, hypertension, and stillbirth. Hence, the study was used to explore the relationship between PE and blood concentration of As in this study. Blood concentration of As during pregnancy was measured by inductively coupled plasma mass spectrometry (ICP-MS). The results shown that the mean blood concentration of As was gradually increased from the control group to the severe PE group (P < 0.0001). Elevated blood concentration of As was associated with the prevalence of PE (OR = 12.81, 95% CI: 2.43-67.39 and 27.55, 1.75-433.43 for middle and high vs. low). Furthermore, elevated blood concentration of As was associated with the severity of PE. Additionally, we observed that blood concentration of As was associated with the hypoproteinemia (P = 0.001, rs = 0.37). Blood concentration of As was negatively corelated with the mean corpuscular volume (MCV) (P = 0.040, rs = - 0.23) and positively corelated with the mean corpuscular hemoglobin concentration (MCHC) (P = 0.044, rs = 0.23). Overall, our results indicated that the blood concentration of As can significantly predict the occurrence of PE. Additionally, we provided evidence that blood concentration of As may affect the occurrence of hypoproteinemia. These findings may provide some ideas for the prevention of PE and pregnancy complications.


Assuntos
Aborto Espontâneo , Arsênio , Hipoproteinemia , Pré-Eclâmpsia , Feminino , Sangue Fetal , Humanos , Recém-Nascido , Gravidez
9.
Phys Rev Lett ; 127(24): 245001, 2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34951808

RESUMO

In inertial confinement approaches to fusion, the asymmetry of target implosion is a major obstacle to achieving high gain in the laboratory. A recently proposed octahedral spherical hohlraum makes it possible to naturally create spherical target irradiation without supplementary symmetry control. Before any decision is made to pursue an ignition-scale laser system based on the octahedral hohlraum, one needs to test the concept with the existing facilities. Here, we report a proof-of-concept experiment for the novel octahedral hohlraum geometry on the cylindrically configured SGIII laser facility without a symmetry control. All polar and equatorial self-emission images of the compressed target show a near round shape of convergence ratio 15 under both square and shaped laser pulses. The observed implosion performances agree well with the ideal spherical implosion simulation. It also shows limitations with using the existing facilities and adds further weight to the need to move to a spherical port geometry for future ignition laser facilities.

10.
BMC Pregnancy Childbirth ; 21(1): 795, 2021 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-34837991

RESUMO

BACKGROUND: The effects of COVID-19 lockdown measures on maternal and fetal health remain unclear. We examined the associations of COVID-19 lockdown with gestational length and preterm birth (PTB) in a Chinese population. METHODS: We obtained medical records of 595,396 singleton live infants born between 2015 and 2020 in 5 cities in Guangdong Province, South China. The exposed group (N = 101,900) included women who experienced the COVID-19 Level I lockdown (1/23-2/24/2020) during pregnancy, while the unexposed group (N = 493,496) included women who were pregnant during the same calendar months in 2015-2019. Cumulative exposure was calculated based on days exposed to different levels of emergency responses with different weighting. Generalized linear regression models were applied to estimate the associations of lockdown exposure with gestational length and risk of PTB (< 37 weeks). RESULTS: The exposed group had a shorter mean gestational length than the unexposed group (38.66 vs 38.74 weeks: adjusted ß = - 0.06 week [95%CI, - 0.07, - 0.05 week]). The exposed group also had a higher risk of PTB (5.7% vs 5.3%; adjusted OR = 1.08 [95%CI, 1.05, 1.11]). These associations seemed to be stronger when exposure occurred before or during the 23rd gestational week (GW) than during or after the 24th GW. Similarly, higher cumulative lockdown exposure was associated with a shorter gestational length and a higher risk of PTB. CONCLUSIONS: The COVID-19 lockdown measures were associated with a slightly shorter gestational length and a moderately higher risk of PTB. Early and middle pregnancy periods may be a more susceptible exposure window.


Assuntos
COVID-19/epidemiologia , Exposição Materna/estatística & dados numéricos , Complicações Infecciosas na Gravidez/epidemiologia , Resultado da Gravidez/epidemiologia , Nascimento Prematuro/epidemiologia , Adulto , China/epidemiologia , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Gravidez , Quarentena , Adulto Jovem
11.
Front Public Health ; 9: 679406, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34277546

RESUMO

Background: Previous studies have demonstrated the embryotoxicity and fetotoxicity of thallium (Tl). However, the effects of prenatal exposure to Tl on birth weight and placental weight and the mediating role of placental weight in the association of Tl with birth weight remain unclear. Methods: We recruited 2,748 participants from the ongoing Prenatal Environment and Offspring Health Cohort (PEOH Cohort) study, which was initiated in 2016 in Guangzhou, China. The Tl concentrations in maternal urine samples collected during the first and third trimester were determined by inductively coupled plasma mass spectrometry. Birth weight and placental weight were extracted from maternal medical records. Results: Pregnant women exposed to the highest tertile of Tl in the first trimester (ß = -42.7 g, 95% CI: -82.3, -3.1 g) and third trimester (ß = -50.6 g, 95% CI: -99.0, -2.3 g) had babies with lower birth weights than those exposed to the lowest tertile. We also found significant negative associations of exposure to Tl concentrations in the first and third trimester with placental weight. Mediation analyses showed that 50.3% (95% CI: 15.9, 79.2%) and 33.5% (95% CI: 1.3, 80.3%) of the effects of Tl exposure in the first and third trimester on birth weight were mediated by decreased placental weight. Conclusion: Our results suggest that prenatal exposure to Tl is negatively associated with birth weight and that this association may be mediated by decreased placental weight.


Assuntos
Efeitos Tardios da Exposição Pré-Natal , Tálio , Peso ao Nascer , China/epidemiologia , Estudos de Coortes , Feminino , Humanos , Lactente , Exposição Materna/efeitos adversos , Placenta , Gravidez , Estudos Prospectivos
12.
Sci Rep ; 11(1): 14492, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34262058

RESUMO

In inertial confinement fusion, quantitative and high-spatial resolution ([Formula: see text]m) measurements of the X-rays self-emitted by the hotspot are critical for studying the physical processes of the implosion stagnation stage. Herein, the 8 ± 0.39-keV monochromatic X-ray distribution from the entire hotspot is quantitatively observed in 5-[Formula: see text]m spatial resolution using a Kirkpatrick-Baez microscope, with impacts from the responses of the diagnosis system removed, for the first time, in implosion experiments at the 100 kJ laser facility in China. Two-dimensional calculations along with 2.5% P2 drive asymmetry and 0.3 ablator self-emission are congruent with the experimental results, especially for the photon number distribution, hotspot profile, and neutron yield. Theoretical calculations enabled a better understanding of the experimental results. Furthermore, the origins of the 17.81% contour profile of the deuterium-deuterium hotspot and the accurate Gaussian source approximation of the core emission area in the implosion capsule are clarified in detail. This work is significant for quantitatively exploring the physical conditions of the hotspot and updating the theoretical model of capsule implosion.

13.
Opt Express ; 29(4): 6133-6146, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33726140

RESUMO

The motion law of complex fluids under extreme conditions is an important aspect of high energy density physics research. It has been demonstrated that using multi-channel curved crystals and a framing camera to observe the laser-produced target pellets doped with tracer elements is an appropriate method for investigating this law. This paper presents a feasible design scheme for a multi-channel toroidal imager, with the ray trace model used to verify the rationality of the evaluation method and the aberration of single toroidal crystal imaging. We demonstrate that the field of view (FOV) consistency of the four-channel Ge(400) toroidal crystal imager is less than 50 µm, while the best spatial resolution is ∼4 µm and the FOV of each channel is >2.2 mm.

14.
Genes Genomics ; 43(4): 361-369, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33555507

RESUMO

BACKGROUND: Recurrent pregnancy loss (RPL) refers to two or more consecutive spontaneous abortion before 24 weeks of gestation, representing 1% of couples of childbearing age. Epigenetic factors including dysregulation of DNA methylation of some genes may play a role in RPL. OBJECTIVE: To identify RPL related genes modulated by DNA methylation expressed in decidua and blood. METHODS: Three decidua samples each from RPL patients and normal controls were recruited to perform genome-wide bisulfite sequencing (GWBS) and transcriptome sequencing. Based on the above results, 22.52 kb of differential methylation regions (DMRs) from 17 genes were verified by bisulfite sequencing PCR at specific region (Hi-MethylSeq) in another 15 decidua (7RPL vs. 8 Controls) and 13 blood (5RPL vs. 8 Controls) samples. RESULTS: 23 genes showed significantly differential cytosine methylation status and distinct expression level between PRL patients and healthy controls synergistically. Three signaling pathways were found to be shared between genes with both hypomethylated differential methylation regions (DMR) and upregulated differential gene expression (DGE). The results from Hi-MethylSeq showed that the hypermethylation of SGK1 in both blood and decidua samples in RPL patients, which was consistent to its lower expression in endometrium reported earlier. SGK3 and CREB5 also showed modulated methylation level in RPL decidua. CONCLUSION: Our finding supported that aberrant methylation of SGK1 and CREB5 could be a cause of the dysregulation of these gens in the endometrium, which is one of cause of reproductive failure. The function of SGK3 in reproduction system deserves further investigation.


Assuntos
Aborto Habitual/genética , Metilação de DNA , Aborto Habitual/metabolismo , Adulto , Proteína A de Ligação a Elemento de Resposta do AMP Cíclico/genética , Decídua/metabolismo , Feminino , Genoma Humano , Humanos , Proteínas Imediatamente Precoces/genética , Gravidez , Proteínas Serina-Treonina Quinases/genética , RNA-Seq , Adulto Jovem
15.
Phys Rev E ; 102(2-1): 023204, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32942472

RESUMO

To study the effects of chunk mixing, the implosion experiments using capsules filled with deuterated foam (CDF capsule) were carried out on the Shenguang laser facility. Three types of the CDF capsules, namely the capsules without Au dopant, with micrometer Au dopant, and with atomic Au dopant, were used in the experiments. The neutron yields, the size, and the emission intensity of the hotspots were measured. The CDF capsules without Au dopant produced the highest neutron yield and the largest hotspot size at the time of peak emission. The capsules with micrometer or atomic Au dopant showed similar reduced neutron yield and hotspot size. The time-resolved hotspot emissions showed different behaviors between different capsules. One-dimensional simulations were carried out to understand the implosion dynamics of the CDF capsule without Au dopant, and to provide the thermodynamic conditions that the Au dopant would experience during the implosion. The effects of Au dopant were then discussed qualitatively.

16.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(4): 1220-1226, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31418383

RESUMO

OBJECTIVE: To evaluate the diagnostic value of high-throughput sequencing (NGS) in screening the thalassemia genes. METHODS: The peripheral blood of 2 858 cases of pre-pregnancy and pregnancy from October 2014 to October 2016 randomly were collected in department of obstetrics, the third people's hospital in Dongguan city. Peripheral blood was used for the blood routine examination, hemoglobin electrophoresis, traditional thalassaemia gene screening and NGS. RESULTS: The rate of missed diagnosis for α-thalassemia and ß-thalassemia using NGS was 0.87% and 1.59%, respectively. Meanwhile, the missed rate of screening for α-thalassemia and ß-thalassemia by traditional screening models was 26.77% and 2.38%, respectively. The area under the ROC curve of α-thalassemia and ß-thalassemia screened by NGS was 0.994 and 0.991, respectively, however, the area under the ROC curve of screening for α-thalassemia and ß-thalassemia by the traditional screening model was 0.866 and 0.988, respectively. The sensitivity, rate of missed diagnosis, Youden index and negative predictive value of screening for α-thalassemia and ß-thalassemia using NGS all were superior to those using traditional screening. CONCLUSION: Compared with the traditional screening model, the NGS screening for thalassemia genes shows a high accuracy, moreover can avoid missed diagnosis resulted from screening by conventional method, suggesting that the NCS possesses the accurate and diagnostic value for screening of thalassemia and can widely apply to clinical practise so as to provid the guarantee for early diagnosis of thalassemia.


Assuntos
Talassemia alfa , Talassemia beta , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Programas de Rastreamento , Gravidez , Curva ROC
17.
Opt Express ; 27(6): 8348-8360, 2019 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-31052654

RESUMO

The development of a polar-view Kirkpatrick-Baez microscope, fielded in the upper polar zone of the Shenguang-III laser fusion facility, is presented. With this microscope, the resolving power of polar-direction X-ray imaging diagnostics is improved, to the 3 ~5 µm scale. The microscope is designed for implosion asymmetry studies, with response energy points at 1.2 keV, 3.5 keV, and 8 keV. A biperiodic multilayer scheme is adopted to accommodate multiple implosion stages. We present the overall optical system design, target aiming scheme, characteristic composite imaging diagnostic experiments and initial results. The inertial-driven quasi-one-dimensional spherical implosions were observed from orthogonal directions with a convergence ratio of ~14.4. Fine features of the stagnating hot spot core are also resolved.

18.
Rev Sci Instrum ; 89(2): 023504, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29495861

RESUMO

The accuracy of the determination of the burn-averaged ion temperature of inertial confinement fusion implosions depends on the unfold process, including deconvolution and convolution methods, and the function, i.e., the detector response, used to fit the signals measured by neutron time-of-flight (nToF) detectors. The function given by Murphy et al. [Rev. Sci. Instrum. 68(1), 610-613 (1997)] has been widely used in Nova, Omega, and NIF. There are two components, i.e., fast and slow, and the contribution of scattered neutrons has not been dedicatedly considered. In this work, a new function, based on Murphy's function has been employed to unfold nToF signals. The contribution of scattered neutrons is easily included by the convolution of a Gaussian response function and an exponential decay. The ion temperature is measured by nToF with the new function. Good agreement with the ion temperature determined by the deconvolution method has been achieved.

19.
Hemoglobin ; 41(4-6): 243-247, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29124980

RESUMO

α-Thalassemia (α-thal) is a very common single gene hereditary disease caused by large deletions or point mutations of the α-globin gene cluster in tropical and subtropical regions of the world. Here, we report for the first time, a novel large α-thal deletion in a Chinese family from Jiangsu Province, People's Republic of China (PRC), which removes almost the entire α2 and α1 genes from the α-globin gene cluster. Thus, it was named the Jiangsu deletion (- -JS) on the α-globin gene cluster causing α0-thal. Heterozygotes for this deletion showed an α-thal trait phenotype with reduced mean corpuscular volume (MCV) and mean corpuscular hemoglobin (Hb) (MCH) levels. The sequencing results showed that a 2538 bp deletion (NG_000006.1: g.35801_38338) existed in this novel genotype on the basis of -α4.2 (leftward), indicating a deletion of about 6.8 kb from the α-globin cluster. In addition, a 29 bp sequence was inserted into the deletion during the recombination events that led to this deletion. Through pedigree analysis, we knew that the proband inherited the novel allele from his mother.


Assuntos
Sequência de Bases , Diagnóstico Pré-Natal , Deleção de Sequência , alfa-Globinas/genética , Talassemia alfa , Feminino , Humanos , Masculino , Gravidez , Talassemia alfa/diagnóstico , Talassemia alfa/genética
20.
Rev Sci Instrum ; 88(6): 063506, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28667965

RESUMO

A coaxial, high performance diamond detector has been developed for neutron diagnostics of inertial confinement fusion at ShenGuangIII laser facility. A Φ10 mm × 1 mm "optical grade" chemical-vapor deposition diamond wafer is assembled in coaxial-designing housing, and the signal is linked to a SubMiniature A connector by the cathode cone. The coaxial diamond detector performs excellently for neutron measurement with the full width at half maximum of response time to be 444 ps for a 50 Ω measurement system. The average sensitivity is 0.677 µV ns/n for 14 MeV (DT fusion) neutrons at an electric field of 1000 V/mm, and the linear dynamic range is beyond three orders of magnitude. The ion temperature results fluctuate widely from the neutron time-of-flight scintillator detector results because of the short flight length. These characteristics of small size, large linear dynamic range, and insensitive to x-ray make the diamond detector suitable to measure the neutron yield, ion temperature, and neutron emission time.

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