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1.
BMC Pregnancy Childbirth ; 24(1): 36, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38182970

RESUMO

BACKGROUND: It is unclear whether the effects of abnormal gestational weight gain (GWG) on birth outcomes are differently in women with different maternal ages. This study aimed to investigate maternal age-specific association between GWG and adverse birth weights in Chinese women older than 30. METHODS: 19,854 mother-child dyads were selected from a prospective cohort study in Southwest China between 2019 and 2022. Logistic regression model was used to assess the association between GWG, which defined by the 2009 Institute of Medicine guidelines, and adverse birth weights including large- and small-for-gestational-age (LGA and SGA), stratified by maternal age (31-34 years and ≥ 35 years). RESULTS: In both maternal age groups, excessive and insufficient GWG were associated with increased odds of LGA and SGA, respectively. After women were categorized by pre-pregnancy body mass index, the associations remained significant in women aged 31-34 years, whereas for women aged ≥ 35 years, the association between excessive GWG and the risk of LGA was only significant in normal weight and overweight/obese women, and the significant effect of insufficient GWG on the risk of SGA was only observed in underweight and overweight/obese women. Moreover, among overweight/obese women, the magnitude of the association between insufficient GWG and the risk of SGA was greater in those aged ≥ 35 years (31-34 years: OR 2.08, 95% CI 1.19-3.55; ≥35 years: OR 2.65, 95% CI 1.47-4.74), while the impact of excessive GWG on the risk of LGA was more pronounced in those aged 31-34 years (31-34 years: OR 2.18, 95% CI 1.68-2.88; ≥35 years: OR 1.71, 95% CI 1.30-2.25). CONCLUSIONS: The stronger associations between abnormal GWG and adverse birth weights were mainly observed in women aged 31-34 years, and more attention should be paid to this age group.


Assuntos
Ganho de Peso na Gestação , Estados Unidos , Gravidez , Feminino , Humanos , Peso ao Nascer , Idade Materna , Estudos Prospectivos , Sobrepeso , Obesidade/epidemiologia , China/epidemiologia
2.
BMC Pregnancy Childbirth ; 23(1): 60, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36694176

RESUMO

BACKGROUND: Gestational weight gain (GWG) criteria recommended by the Institute of Medicine may not be appropriate for Asians. Our aims are to investigate the association between GWG and adverse pregnancy outcomes, and to propose optimal total GWG and rates of GWG for Chinese women. METHODS: Prospective data of 51,125 mother-child pairs from 27 hospitals and community health care centers from Guizhou, Yunnan and Sichuan provinces in China between 2014 and 2018 were analyzed. Generalized Additive Models were performed to determine the associations of GWG with the risk of aggregated adverse outcomes (gestational diabetes mellitus, preeclampsia, cesarean delivery, stillbirth, preterm birth, macrosomia, large for gestational age, and small for gestational age). The range that did not exceed a 2.5% increase from the lowest risk of aggregated adverse outcomes was defined as the optimal GWG range. RESULTS: Among all participants, U-shaped prospective association was found between GWG and the risk of aggregated adverse pregnancy outcomes. The optimal GWG range of 8.2-13.0 kg was proposed for underweight, 7.3-12.5 kg for normal weight, and 2.0-9.4 kg for overweight/obese women. Meanwhile, a higher GWG rate in the first two trimesters than that in the last trimester was suggested, except for overweight/obese women. After stratified by maternal age, mothers ≥35 years were suggested to gain less weight compared to younger mothers. CONCLUSIONS: To keep a balance between maternal health and neonatal growth, optimal GWG ranges based on Asia-specific BMI categories was suggested for Chinese women with different pre-gravid BMIs and maternal ages.


Assuntos
Sobrepeso , Nascimento Prematuro , Feminino , Gravidez , Recém-Nascido , Humanos , Adulto , Sobrepeso/complicações , Gestantes , População do Leste Asiático , China/epidemiologia , Nascimento Prematuro/epidemiologia , Aumento de Peso , Obesidade/epidemiologia , Obesidade/complicações , Resultado da Gravidez/epidemiologia , Índice de Massa Corporal
3.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 54(2): 426-431, 2023 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-36949710

RESUMO

Objective: To compare the pregnancy outcomes of pregnancy outcomes after selective fetal reduction treatment in monochorionic, dichorionic, and trichorionic triplet pregnancies. Methods: We conducted a retrospective analysis of the clinical data of 118 pregnant women carrying triplets. All subjects underwent regular prenatal check-ups and were admitted for delivery at West China Second University Hospital, Sichuan University between January 1, 2012 and January 31, 2021. According to the chorionicity, the subjects were divided into a monochorionic group ( n=13), a dichorionic group ( n=44), and a trichorionic group ( n=61). Within each group, the subjects were further divided into two subgroups, a reduction group and an expectant treatment group, according to whether they underwent fetal reduction or not. The clinical data and pregnancy outcomes were compared between the subgroups within each group. Results: In the monichorionic group, the reduction subgroup had a lower preterm birth rate and higher neonatal birth body mass than those of the expectant management subgroup, but the differences were not statistically significant. In the dichorionic and trichorionic groups, the rates of preterm delivery, neonatal hospitalization, and serious complications of the reduction subgroups were lower than those of the expectant subgroups ( P<0.05), while the neonatal birth body mass was higher in the reduction subgroups than that in the expectant subgroups ( P<0.05). In the dichorionic group, the incidence of intrahepatic cholestasis during pregnancy was lower in the reduction subgroup than that in the expectant treatment subgroup. In all 3 groups, there was no statistically significant difference between the subgroups in the incidence of gestational diabetes, hypertensive disorders of pregnancy, premature rupture of membranes, and postpartum hemorrhage. The survival curve analysis showed that women receiving fetal reduction during the first trimester had a lower risk of pregnancy loss and more significant prolonged of gestational age than those undergoing the procedure during the second trimester. Conclusion: Fetal reduction of triplets can significantly prolong the gestational age and improve the perinatal prognosis. In addition, selective reduction in the first trimester may lead to greater benefits than selective reduction in the second trimester does.


Assuntos
Gravidez de Trigêmeos , Nascimento Prematuro , Gravidez , Feminino , Recém-Nascido , Humanos , Resultado da Gravidez , Redução de Gravidez Multifetal , Estudos Retrospectivos , Nascimento Prematuro/epidemiologia , Idade Gestacional , Gravidez de Gêmeos
4.
BMC Pregnancy Childbirth ; 22(1): 269, 2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35361142

RESUMO

BACKGROUND: Intrahepatic cholestasis of pregnancy is one of the common complications during pregnancy, and ursodeoxycholic acid has been recommended as the first-line drug. However, if the assisted reproductive technology may increase adverse perinatal outcomes of twin pregnancies complicated by intrahepatic cholestasis is disputed, we aimed to investigate perinatal outcomes between twin pregnancies by assisted reproductive technology versus spontaneous conception, based on these women accepted ursodeoxycholic acid treatment. METHODS: From January 2014 to January 2019, we retrospectively analysed the clinical data of twin pregnant women with intrahepatic cholestasis, excluding those who did not receive ursodeoxycholic acid treatment. In total, 864 women were included, among whom 500 conceived by assisted reproductive technology and 364 conceived by spontaneous conception. The primary assessment for perinatal outcomes included premature birth, meconium-stained amniotic fluid, low Apgar score, neonatal intensive care unit and still birth, and secondary indicators were serum bile acid and liver enzymes level during medication, so we also finished subgroup analysis based on different elevated bile acid level and drug usage. The statistical analysis was performed by SPSS 22.0. RESULTS: The study demonstrated that compared to spontaneous conception, assisted reproductive technology conceived twin pregnancies diagnosed as intrahepatic cholestasis earlier (p = 0.003), and lower birth weight (p = 0.001), less incidence of preterm delivery (p = 0.000) and neonatal intensive care unit admission (p = 0.001), but the rate of meconium-stained amniotic fluid, low Apgar score and still birth have no statistic differences. Moreover, the subgroup analysis showed no significant difference in elevated bile acid levels and medication between assisted reproductive technology and spontaneous conception groups. CONCLUSIONS: The assisted reproductive technology may increase the risk of early-onset intrahepatic cholestasis in twin pregnancies, but it does not seem to increase adverse effects on bile acid levels and perinatal outcomes. Regardless of ursodeoxycholic acid used alone or combination, the effect of bile acid reduction and improving perinatal outcomes in twin pregnancies is limited. Our conclusions still need more prospective randomized controlled studies to confirm.


Assuntos
Colestase Intra-Hepática , Gravidez de Gêmeos , Colestase Intra-Hepática/epidemiologia , Feminino , Humanos , Recém-Nascido , Gravidez , Resultado da Gravidez/epidemiologia , Estudos Prospectivos , Técnicas de Reprodução Assistida/efeitos adversos , Estudos Retrospectivos
5.
J Obstet Gynaecol Res ; 48(1): 66-72, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34657360

RESUMO

OBJECTIVE: To provide evidence for the diagnosis of listeriosis through a retrospective study of clinical features and results of pregnant women infected with listeriosis. METHODS: Twenty-nine pregnant women infected with listeriosis visiting West China Second University Hospital affiliated to Sichuan University from July 2010 to February 2019 were included in the retrospective analysis. Data like general information, clinical symptoms, laboratory results, and pathogen detection were analyzed to conclude clinical characteristics. RESULTS: The median age of 29 patients was 28 (18.0-42.0). Nine individuals visited in the second trimester, while 20 in the last trimester. The median course before visiting was 3.4 (0.1-19) days. The main symptoms of the first attendance were fever (21/29), increased white blood cells (26/29), abdominal pain (16/29), and decreased or vanished fetal movements (7/29). Samples where listeria were identified were maternal blood (14 cases), excreta from birth canal (24 cases), placenta (one case), newborn blood (seven cases), newborn sputum (eight cases), newborn excreta from auditory meatus (three cases), cerebrospinal fluid (two cases) and ocular discharge (one case). Inflammation was detected in pathological examination of placenta in all subjects. Among them, three were diagnosed with mild chorioamnionitis; five with moderate chorioamnionitis; nine with moderate-to-severe chorioamnionitis and 12 with severe chorioamnionitis. Among 33 fetuses carried by 29 subjects, fetal outcomes include six miscarriages, nine stillbirths, four newborn deaths immediately after birth and four after treatment discontinuation, nine discharges after successful treatment in hospital, and one death after treatment. As for maternal outcomes, 29 pregnant women all recovered after delivery. CONCLUSION: With the acute onset, high incidence of adverse pregnancy outcomes and low coverage of initial treatment, clinical physicians need to raise the awareness of listeriosis during pregnancy.


Assuntos
Listeria monocytogenes , Listeriose , Complicações Infecciosas na Gravidez , Feminino , Humanos , Listeriose/diagnóstico , Listeriose/epidemiologia , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/epidemiologia , Resultado da Gravidez , Estudos Retrospectivos
6.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 53(1): 137-141, 2022 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-35048614

RESUMO

OBJECTIVE: To study the effect of using ursodeoxycholic acid (UDCA) to treat monochorionic and dichorionic twin pregnancies complicated by intrahepatic cholestasis of pregnancy (ICP) and to examine the differences in perinatal outcomes. METHODS: A total of 406 twin-carrying pregnant women who had ICP and received care at West China Second Hospital, Sichuan University between January 1, 2015 and November 1, 2018 were included in the study. The clinical data of monochorionic diamniotic (MCDA) and dichorionic diamniotic (DCDA) twins with ICP were analyzed. Analysis was done to compare the treatment effect for lowering serum total bile acid (TBA) and the perinatal outcomes with simple UDCA medication or combination medication. RESULTS: There were no statistically significant differences in TBA levels, early-onset ICP, simple UDCA medication or combination medication, neonatal Apgar score, birth weight, length of hospital stay, C-section rate, and perinatal mortality between the MCDA and the DCDA twin groups with ICP. However, maternal age, BMI, scarred uterus, in vitro fertilization-embryo transfer, preeclampsia, twin comorbidity rate of the two groups showed statistical differences. Further comparison between twin pregnancies with mildly-elevated TBA and those with severely-elevated TBA showed significant difference in preterm birth rate ( P<0.05). CONCLUSION: Simple UDCA medication or combination medication may have the same therapeutic effect on MCDA and DCDA twin pregnancies with ICP. Monochorionic twin pregnancy, twin comorbidities and pregnancy complications were still important factors affecting pregnancy outcomes of twin pregnancies with ICP. Twin pregnancies with slightly elevated TBA have been managed as severe ICP, which may be associated with increased iatrogenic preterm births.


Assuntos
Colestase Intra-Hepática , Nascimento Prematuro , Colestase Intra-Hepática/complicações , Colestase Intra-Hepática/tratamento farmacológico , Feminino , Humanos , Recém-Nascido , Gravidez , Complicações na Gravidez , Resultado da Gravidez , Gravidez de Gêmeos , Estudos Retrospectivos , Ácido Ursodesoxicólico/uso terapêutico
7.
Eur J Nutr ; 60(6): 3461-3472, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33661377

RESUMO

PURPOSE: Studies regarding the association between dietary fat intake and gestational diabetes mellitus (GDM) are limited and provide conflicting findings. Thus, the study aims to examine the association of dietary fat intake in the year preceding pregnancy and during pregnancy with the risk of GDM, taking the relevance of dietary protein intake on GDM into consideration. METHODS: A prospective study was conducted in 6299 singleton pregnancies, using the data from the Nutrition in Pregnancy and Growth in Southwest China (NPGSC). A validated food frequency questionnaire was used to assess dietary fat intake in the year preceding pregnancy and during the first and second trimesters of pregnancy. Logistic regression analysis was used to assess the prospective associations of dietary fat intake and the type and source of dietary fats in different time windows with GDM risk. RESULTS: Higher intake of total fat [OR (95% CI): 2.21 (1.19-4.20), P = 0.02] during 12-22 weeks of gestation was associated with higher GDM risk. However, adjustment for animal protein intake greatly attenuated this association [OR (95% CI): 1.81 (0.93, 3.64), P = 0.11]. Total fat intake neither in the year preceding pregnancy nor during the early pregnancy was associated with GDM risk. Moreover, insignificant associations were observed between intakes of vegetable fat, animal fat, cholesterol, saturated fatty acid, monounsaturated fatty acid and polyunsaturated fatty acid one year before pregnancy and during the first and second trimesters and GDM risk. CONCLUSION: Our study indicated that dietary fat intake one year before pregnancy and across the two pregnancy trimesters preceding the diagnosis of GDM has no relevance on GDM risk among Chinese women, particularly those with normal BMI, low, or normal calorie intake.


Assuntos
Diabetes Gestacional , Animais , Diabetes Gestacional/epidemiologia , Dieta , Gorduras na Dieta , Proteínas Alimentares , Feminino , Humanos , Gravidez , Estudos Prospectivos , Fatores de Risco
8.
Proc Natl Acad Sci U S A ; 115(15): 3770-3775, 2018 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-29581262

RESUMO

The increasing demands for efficient and clean energy-storage systems have spurred the development of Li metal batteries, which possess attractively high energy densities. For practical application of Li metal batteries, it is vital to resolve the intrinsic problems of Li metal anodes, i.e., the formation of Li dendrites, interfacial instability, and huge volume changes during cycling. Utilization of solid-state electrolytes for Li metal anodes is a promising approach to address those issues. In this study, we use a 3D garnet-type ion-conductive framework as a host for the Li metal anode and study the plating and stripping behaviors of the Li metal anode within the solid ion-conductive host. We show that with a solid-state ion-conductive framework and a planar current collector at the bottom, Li is plated from the bottom and rises during deposition, away from the separator layer and free from electrolyte penetration and short circuit. Owing to the solid-state deposition property, Li grows smoothly in the pores of the garnet host without forming Li dendrites. The dendrite-free deposition and continuous rise/fall of Li metal during plating/stripping in the 3D ion-conductive host promise a safe and durable Li metal anode. The solid-state Li anode shows stable cycling at 0.5 mA cm-2 for 300 h with a small overpotential, showing a significant improvement compared with reported Li anodes with ceramic electrolytes. By fundamentally eliminating the dendrite issue, the solid Li metal anode shows a great potential to build safe and reliable Li metal batteries.

9.
Paediatr Perinat Epidemiol ; 34(6): 724-733, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32597516

RESUMO

BACKGROUND: Pregnancy and birth cohorts addressing maternal nutrition and its impact on health outcomes have been rare in China, especially in Southwest China. OBJECTIVES: To describe the design, implementation, baseline characteristics, and initial results of the Nutrition in Pregnancy and Growth in Southwest China (NPGSC) cohort. POPULATION: Pregnant women with their children in Southwest China. DESIGN: NPGSC participants have been prospectively recruited since 2014. Pregnant women were invited to participate in the study at their first routine ultrasound examination in gestational weeks 9-11. Data were assessed three times during pregnancy (9-11, 20-22, and 33-35 gestation weeks), and eight times in infants and toddlers. METHODS: Pre-pregnancy body weight and height were self-reported; gestational weight gain was measured at regular intervals. Both food frequency questionnaires (FFQ) and 24-hour dietary recalls were used to collect dietary intakes during pregnancy, and FFQ for diet before pregnancy. Information on pregnancy outcomes was extracted from the medical birth registry. Anthropometry of children in the first 3 years of life was measured by trained investigators. Other child outcomes, including feeding practices (self-reported by mothers) and cognitive development (assessed by the Chinese version of Ages and Stages Questionnaire), were recorded. PRELIMINARY RESULTS: Between 2014 and 2018, 12 989 pregnant women were enrolled, and 2296 children completed the 3 years follow-up. Among them, 115 pregnancies ended in stillbirth. Mean maternal pre-pregnancy BMI was 21.1 kg/m2 and mean gestational weight gain was 13.5 kg 18.6% of mothers developed gestational diabetes and 1.5% of mothers were diagnosed with preeclampsia. Mean birthweight and birth length of children were, respectively, 3329 g and 49.4 cm. CONCLUSION: We built a prospective cohort in Southwest China, which can provide valuable data to investigate the relevance of nutrition for the health of mothers and children.


Assuntos
Resultado da Gravidez , Aumento de Peso , Peso ao Nascer , China/epidemiologia , Feminino , Humanos , Gravidez , Resultado da Gravidez/epidemiologia , Estudos Prospectivos
10.
Nutr J ; 19(1): 95, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32907571

RESUMO

BACKGROUND: Early age at menarche is associated with risk of several chronic diseases. Prospective study on the association between dietary pattern and timing of menarche is sparse. We examined whether dietary patterns prior to the menarche onset were prospectively associated with menarcheal age in Chinese girls. METHODS: One thousand one hundred eighteen girls aged 6-13 y in the China Health and Nutrition Survey (CHNS) with three-day 24-h recalls and information on potential confounders at baseline were included in the study. Dietary patterns were identified using principal component analysis. Age at menarche was self-reported at each survey. Cox proportional hazard regression models were performed to examine the associations of premenarcheal dietary patterns and menarcheal timing. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated. RESULTS: Three major dietary patterns were identified: modern dietary pattern, animal food pattern, and snack food pattern. After adjustment for age at baseline, region, ethnicity, maternal education level, energy intake at baseline, and body mass index Z-score at baseline, girls in the highest quartile of modern dietary pattern score had a 33% higher probability of experiencing menarche at an earlier age than those in the lowest quartile (HR: 1.33, 95% CI: 1.002-1.77, p for trend = 0.03). No significant association was found for the animal food pattern or snack food pattern. CONCLUSIONS: Higher adherence to modern dietary pattern during childhood is associated with an earlier menarcheal age. This association was independent of premenarcheal body size.


Assuntos
Dieta , Menarca , Animais , Índice de Massa Corporal , China/epidemiologia , Feminino , Humanos , Inquéritos Nutricionais , Estudos Prospectivos
11.
Med Sci Monit ; 26: e923959, 2020 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-32740647

RESUMO

Females are highly predisposed to the occurrence of migraine, a recurrent neurovascular headache disorder. Although migraine improves or disappears during pregnancy, a significant association between migraine and hypertension (i.e., pre-eclampsia) or vascular complications (i.e., stroke) during gestation has been determined. Low-dose aspirin exerts an antithrombotic effect and can improve vascular resistance by regulating endothelial function, which are implicated in the pathogenesis of migraine, pre-eclampsia, and other vascular complications during pregnancy. Low-dose aspirin is widely used prophylactically in the general population who are at higher risk of developing stroke or in pregnant women at higher risk of pre-eclampsia. In this paper we discuss the recent trends in research on the relationship between migraine and pre-eclampsia, an issue of paramount importance in obstetric care, and the potential relationship between migraine and vascular complications in pregnant women. In addition, the potential validity of low-dose aspirin prophylaxis in pregnant women with migraine is explored.


Assuntos
Aspirina/uso terapêutico , Transtornos de Enxaqueca/tratamento farmacológico , Inibidores da Agregação Plaquetária/uso terapêutico , Pré-Eclâmpsia/tratamento farmacológico , Complicações Cardiovasculares na Gravidez/tratamento farmacológico , Acidente Vascular Cerebral/prevenção & controle , Esquema de Medicação , Cálculos da Dosagem de Medicamento , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiopatologia , Feminino , Humanos , Transtornos de Enxaqueca/complicações , Transtornos de Enxaqueca/fisiopatologia , Pré-Eclâmpsia/fisiopatologia , Gravidez , Complicações Cardiovasculares na Gravidez/fisiopatologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/fisiopatologia
12.
J Public Health (Oxf) ; 41(2): 250-258, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29924330

RESUMO

BACKGROUND: Little is known about the relationships between diet cost, dietary intake and obesity in Chinese populations. This study explored how diet cost was related to diet quality and obesity among school-aged children in Southwest China. METHODS: Data from a cross-sectional study was analysed. Diet cost was estimated based on dietary intake assessed with 24-h dietary recalls and retail food prices. Diet quality was measured using the Chinese Children Dietary Index. Body height, weight, waist circumference and skinfold thicknesses were measured, and their body mass index standard deviation score (BMISDS), waist-to-height ratio (WHtR), fat mass index (FMI) and fat-free mass index (FFMI) were calculated. Multivariate regression models were used to explore the relevance of diet cost to diet quality and obesity. RESULTS: After adjustment for potential confounders, a positive association was observed between diet quality and energy-adjusted diet cost (ß = 0.143, 95% confidence interval, CI: 0.014-0.285, Pfor-trend = 0.0006). Energy-adjusted diet cost also showed a positive association with FMI (ß = 0.0354, 95% CI: 0.0001-0.0709, Pfor-trend = 0.01), BMISDS (ß = 0.0200, 95% CI: 0.0006-0.0394, Pfor-trend = 0.002) and WHtR (ß = 0.0010, 95% CI: 0.0003-0.0017, Pfor-trend = 0.02). CONCLUSIONS: Energy-adjusted diet cost was independently and positively associated with diet quality and obesity among Chinese school-aged children.


Assuntos
Dieta Saudável/economia , Alimentos/economia , Obesidade Infantil/epidemiologia , Adolescente , Criança , China/epidemiologia , Custos e Análise de Custo , Estudos Transversais , Dieta/economia , Dieta/estatística & dados numéricos , Dieta Saudável/estatística & dados numéricos , Feminino , Humanos , Masculino , Obesidade Infantil/economia
13.
Proc Natl Acad Sci U S A ; 113(26): 7094-9, 2016 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-27307440

RESUMO

Beyond state-of-the-art lithium-ion battery (LIB) technology with metallic lithium anodes to replace conventional ion intercalation anode materials is highly desirable because of lithium's highest specific capacity (3,860 mA/g) and lowest negative electrochemical potential (∼3.040 V vs. the standard hydrogen electrode). In this work, we report for the first time, to our knowledge, a 3D lithium-ion-conducting ceramic network based on garnet-type Li6.4La3Zr2Al0.2O12 (LLZO) lithium-ion conductor to provide continuous Li(+) transfer channels in a polyethylene oxide (PEO)-based composite. This composite structure further provides structural reinforcement to enhance the mechanical properties of the polymer matrix. The flexible solid-state electrolyte composite membrane exhibited an ionic conductivity of 2.5 × 10(-4) S/cm at room temperature. The membrane can effectively block dendrites in a symmetric Li | electrolyte | Li cell during repeated lithium stripping/plating at room temperature, with a current density of 0.2 mA/cm(2) for around 500 h and a current density of 0.5 mA/cm(2) for over 300 h. These results provide an all solid ion-conducting membrane that can be applied to flexible LIBs and other electrochemical energy storage systems, such as lithium-sulfur batteries.

14.
Nano Lett ; 18(6): 3926-3933, 2018 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-29787678

RESUMO

Solid-state electrolytes (SSEs) have been widely considered as enabling materials for the practical application of lithium metal anodes. However, many problems inhibit the widespread application of solid state batteries, including the growth of lithium dendrites, high interfacial resistance, and the inability to operate at high current density. In this study, we report a three-dimensional (3D) mixed electron/ion conducting framework (3D-MCF) based on a porous-dense-porous trilayer garnet electrolyte structure created via tape casting to facilitate the use of a 3D solid state lithium metal anode. The 3D-MCF was achieved by a conformal coating of carbon nanotubes (CNTs) on the porous garnet structure, creating a composite mixed electron/ion conductor that acts as a 3D host for the lithium metal. The lithium metal was introduced into the 3D-MCF via slow electrochemical deposition, forming a 3D lithium metal anode. The slow lithiation leads to improved contact between the lithium metal anode and garnet electrolyte, resulting in a low resistance of 25 Ω cm2. Additionally, due to the continuous CNT coating and its seamless contact with the garnet we observed highly uniform lithium deposition behavior in the porous garnet structure. With the same local current density, the high surface area of the porous garnet framework leads to a higher overall areal current density for stable lithium deposition. An elevated current density of 1 mA/cm2 based on the geometric area of the cell was demonstrated for continuous lithium cycling in symmetric lithium cells. For battery operation of the trilayer structure, the lithium can be cycled between the 3D-MCF on one side and the cathode infused into the porous structure on the opposite side. The 3D-MCF created by the porous garnet structure and conformal CNT coating provides a promising direction toward new designs in solid-state lithium metal batteries.

15.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 50(1): 83-87, 2019 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-31037910

RESUMO

OBJECTIVE: To determine the associations of pre-pregnancy body mass index (BMI) and gestational weight gain (GWG) with gestational diabetes mellitus (GDM). METHODS: A prospective cohort of pregnant women were screened for GDM at 24-28 weeks of gestation between 2013 and 2015, resulting in a sample of 3 593 with GDM and 15 346 without GDM. The body mass, plasma glucose, and height data of the participants were collected by the local medical workers. Multivariate logistic regression analyses were performed to determine the associations of pre pregnancy body mass index and weight gain during pregnancy with GDM. RESULTS: The participants with pre pregnancy overweight [odds ratio(OR)=2.44, 95% cofidence interval(CI)1.98-2.99] and obesity (OR=4.98, 95%CI 2.52-9.91) were more likely to develop GDM. According to the Institute of Medicine (IOM) criteria, excessive GWG in the first trimester occurred in 8.46% of the women, compared with 55.07% in the second trimester. After adjustment for age at delivery and pre pregnancy BMI, high GWG in the first trimesters in advanced maternal age (age at delivery≥35 yr.) group (OR=1.42, 95%CI 1.02-2.28) was a risk factor for GDM while the OR value of the non-advanced maternal age (age at delivery≤35 yr.) group was not statistically significant. In second trimesters, both advanced maternal age group (OR=1.59, 95%CI 1.14-1.88) and non-advanced maternal age group (OR=1.49, 95%CI 1.20-1.72) in high GWG were associated with high risk of GDM. CONCLUSION: Pre pregnancy overweight and obesity and excessive GWG during early and second trimesters of pregnancy may increase the risk of GDM in women in Southwestern China.


Assuntos
Diabetes Gestacional , Índice de Massa Corporal , China , Feminino , Ganho de Peso na Gestação , Humanos , Gravidez , Estudos Prospectivos
16.
Nat Mater ; 16(5): 572-579, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27992420

RESUMO

Garnet-type solid-state electrolytes have attracted extensive attention due to their high ionic conductivity, approaching 1 mS cm-1, excellent environmental stability, and wide electrochemical stability window, from lithium metal to ∼6 V. However, to date, there has been little success in the development of high-performance solid-state batteries using these exceptional materials, the major challenge being the high solid-solid interfacial impedance between the garnet electrolyte and electrode materials. In this work, we effectively address the large interfacial impedance between a lithium metal anode and the garnet electrolyte using ultrathin aluminium oxide (Al2O3) by atomic layer deposition. Li7La2.75Ca0.25Zr1.75Nb0.25O12 (LLCZN) is the garnet composition of choice in this work due to its reduced sintering temperature and increased lithium ion conductivity. A significant decrease of interfacial impedance, from 1,710 Ω cm2 to 1 Ω cm2, was observed at room temperature, effectively negating the lithium metal/garnet interfacial impedance. Experimental and computational results reveal that the oxide coating enables wetting of metallic lithium in contact with the garnet electrolyte surface and the lithiated-alumina interface allows effective lithium ion transport between the lithium metal anode and garnet electrolyte. We also demonstrate a working cell with a lithium metal anode, garnet electrolyte and a high-voltage cathode by applying the newly developed interface chemistry.

17.
BMC Endocr Disord ; 18(1): 25, 2018 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-29739382

RESUMO

BACKGROUND: Recent epidemiological studies have suggested inverse associations between vitamin D status and metabolic diseases including type 2 diabetes (T2DM). The aim of this study was to examine whether a higher serum 25-hydroxyvitamin D (25(OH)D) was associated with a more favorable glucose homeostasis among adults without diabetes in Southwest China. METHODS: Serum 25(OH)D concentration was measured in a cross-sectional sample of 1514 adults without diabetes aged 25-65 years recruited from Southwest China. Indices describing glucose homeostasis included fasting plasma glucose (FPG), fasting insulin, glycated hemoglobin (HbA1c), the homeostatic model assessment 2-insulin resistance (HOMA2-IR) and odds of pre-diabetes. Data were analyzed by multivariable-adjusted regression models. RESULTS: The average serum 25(OH)D was 22.66 ng/ml, and percentages of vitamin D deficiency [25(OH)D < 20 ng/ml], insufficiency [20 ≤ 25(OH)D ≤ 30 ng/ml] were 47.6 and 32.2%, respectively. Serum 25(OH)D was inversely associated with fasting insulin (P = 0.0007), HbA1c (P = 0.0001) and HOMA2-IR (P = 0.0007), but not with FPG, after adjusting for age, gender, monthly personal income, smoking status, energy intake, moderate-to-vigorous physical activity (MVPA) and waist circumference (WC). Compared with the lowest 25(OH)D tertile, the odds ratio for pre-diabetes in the highest tertile was 0.68 (95%CI: 0.47-0.99) after adjustment for cofounders. In the following stratified analyses according to weight status, we only observed this inverse association between serum 25(OH)D and pre-diabetes in overweight or obese adults (n = 629, P = 0.047), but not in their counterparts with BMI < 24 kg/m2. CONCLUSIONS: Our results advocate that a higher serum 25(OH)D level is associated with decreased risk of impairment of glucose homeostasis among adults without diabetes in Southwest China. Further studies are warranted to determine the role of vitamin D in glucose homeostasis.


Assuntos
Biomarcadores/metabolismo , Diabetes Mellitus Tipo 2/prevenção & controle , Glucose/metabolismo , Homeostase , Deficiência de Vitamina D/complicações , Vitamina D/análogos & derivados , Adulto , Idoso , Estudos Transversais , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/etiologia , Feminino , Seguimentos , Humanos , Resistência à Insulina , Masculino , Pessoa de Meia-Idade , Prognóstico , Vitamina D/sangue
18.
Public Health Nutr ; 21(10): 1827-1834, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29458444

RESUMO

OBJECTIVE: Dietary energy density (ED) might have influences on body composition. We therefore examined whether ED is associated with body composition among Chinese adults. DESIGN: We collected dietary data through validated two-day 24 h recalls. ED, defined as the amount of energy per unit weight of food consumed, was calculated based on five methods. Multiple linear regression analyses were performed to explore the associations between ED and body composition parameters, including BMI, fat mass index (FMI), fat-free mass index (FFMI), percentage body fat (%BF) and waist circumference (WC). SETTING: Southwest China. SUBJECTS: Chinese adults (n 1933) in 2013. RESULTS: After adjusting the covariates, all ED definitions were positively associated with BMI, FMI, FFMI, %BF and WC among women (P<0·01). In men, however, ED with foods only was positively associated with BMI, FMI, FFMI and %BF (P<0·05), but not with WC (P=0·07); we also found null associations between ED with foods and all beverages and body composition among men. Additionally, ED contributed to higher increases of body composition in women than in men (P<0·01). CONCLUSIONS: The present study supports the positive association between ED and body composition among adults in Southwest China, in which beverages may play an important role.


Assuntos
Composição Corporal/fisiologia , Dieta/estatística & dados numéricos , Ingestão de Alimentos/fisiologia , Adulto , China/epidemiologia , Estudos Transversais , Registros de Dieta , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
Nano Lett ; 17(1): 565-571, 2017 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-27936780

RESUMO

Solid-state electrolytes are known for nonflammability, dendrite blocking, and stability over large potential windows. Garnet-based solid-state electrolytes have attracted much attention for their high ionic conductivities and stability with lithium metal anodes. However, high-interface resistance with lithium anodes hinders their application to lithium metal batteries. Here, we demonstrate an ultrathin, conformal ZnO surface coating by atomic layer deposition for improved wettability of garnet solid-state electrolytes to molten lithium that significantly decreases the interface resistance to as low as ∼20 Ω·cm2. The ZnO coating demonstrates a high reactivity with lithium metal, which is systematically characterized. As a proof-of-concept, we successfully infiltrated lithium metal into porous garnet electrolyte, which can potentially serve as a self-supported lithium metal composite anode having both high ionic and electrical conductivity for solid-state lithium metal batteries. The facile surface treatment method offers a simple strategy to solve the interface problem in solid-state lithium metal batteries with garnet solid electrolytes.

20.
Nano Lett ; 17(8): 4917-4923, 2017 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-28714694

RESUMO

High-temperature batteries require the battery components to be thermally stable and function properly at high temperatures. Conventional batteries have high-temperature safety issues such as thermal runaway, which are mainly attributed to the properties of liquid organic electrolytes such as low boiling points and high flammability. In this work, we demonstrate a truly all-solid-state high-temperature battery using a thermally stable garnet solid-state electrolyte, a lithium metal anode, and a V2O5 cathode, which can operate well at 100 °C. To address the high interfacial resistance between the solid electrolyte and cathode, a rapid thermal annealing method was developed to melt the cathode and form a continuous contact. The resulting interfacial resistance of the solid electrolyte and V2O5 cathode was significantly decreased from 2.5 × 104 to 71 Ω·cm2 at room temperature and from 170 to 31 Ω·cm2 at 100 °C. Additionally, the diffusion resistance in the V2O5 cathode significantly decreased as well. The demonstrated high-temperature solid-state full cell has an interfacial resistance of 45 Ω·cm2 and 97% Coulombic efficiency cycling at 100 °C. This work provides a strategy to develop high-temperature all-solid-state batteries using garnet solid electrolytes and successfully addresses the high contact resistance between the V2O5 cathode and garnet solid electrolyte without compromising battery safety or performance.

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