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1.
Chemosphere ; 313: 137431, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36455656

RESUMO

Despite the longstanding evidence on the effect of air pollutants on preterm birth (PTB), few studies have focused on its subtypes, including spontaneous preterm birth (sPTB) and medically indicated preterm birth (miPTB). Most studies evaluated only the short-term or long-term effects of particulate matter (PM) on PTB. Thus, we designed this study, based on a cohort of 179,385 women, to evaluate both short- and long-term effects of PM with diameters ≤2.5 µm and ≤10 µm (PM2.5 and PM10) on PTB, sPTB and miPTB in Shanghai. Generalized additive models (GAMs) were applied to evaluate short-term effects. Lagged effects were identified using different lag structures. Exposure-response correlation curves were plotted using GAMs after adjustment for confounders. ORs and 95% CIs were calculated using logistic regression to estimate the long-term effect after adjustment for confounders. There was 5.67%, 3.70% and 1.98% daily incidence of PTB, sPTB, and miPTB on average. Every 10 µg/m3 increase in PM2.5 and PM10 was positively associated with PTB and sPTB at lag 2 day. The exposure-response curves (lag 2 day) indicated a rapid increase in sPTB for PM2.5 and a linear increase for PM10, in PTB for PM2.5 and PM10 at concentrations over 100 µg/m3. Regarding long-term exposure, positive associations were found between 10 µg/m3 increases in PM2.5 and PM10 in 3rd trimester and greater odds of sPTB (aOR: 1.042, 95% CI: 1.018-1.065, and 1.018, 95% CI:1.002-1.034), and during the 3 months before conception and miPTB (aOR: 1.023, 95% CI: 1.003-1.042, and 1.017, 95% CI: 1.000-1.036). Acute exposure to PM2.5 and PM10 at lag 2 day and chronic exposure in 3rd trimester was significantly associated with sPTB, while miPTB was related to chronic exposure during the 3 months before pregnancy. These findings indicate that susceptibility windows of PM exposure can be influenced by different underlying etiologies of PTB.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Nascimento Prematuro , Gravidez , Recém-Nascido , Humanos , Feminino , Material Particulado/análise , Nascimento Prematuro/epidemiologia , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , China/epidemiologia , Poluentes Atmosféricos/análise , Exposição Materna/efeitos adversos
2.
Dalton Trans ; 51(33): 12494-12501, 2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-35916624

RESUMO

The development of stable, Earth-abundant, and high-activity molecular water oxidation catalysts under acidic and neutral conditions remains a great challenge. Here, the use of N-heterocyclic carbene (NHC)-based iron(III) complex 1 {[phenyl(tris(3-methylimidazol-1-ylidene))borate]2Fe(III)}+ as a catalyst for water oxidation under acidic and neutral conditions was investigated. Two iron(II) carbene complexes, 2 {[2,6-bis(3-methylimidazolium-1-yl)pyridine]2Fe}2+ and 3 {[2,6-bis(3-methylimidazolium-1-yl)pyridine-4-carboxylic acid]2Fe}2+, were also used for comparison. A series of experiments demonstrate that complex 1 has excellent performance in terms of both catalytic activity and stability. In addition, the faradaic efficiency and turnover frequency (TOF) reach 95.0% and 2.8 s-1, respectively. An overpotential of ca. 490 mV is obtained at pH 1.5. Density functional theory (DFT) calculations indicate that dehydrogenation is the potential-determining step (PDS) in water oxidation. Complex 1 has a lower free energy barrier in this process than 2 and 3. High-valent Fe species are further proven in 1 by spectroelectrochemical measurements, which are crucial in promoting water oxidation. This study is expected to contribute to the development of homogeneous water oxidation catalysis under acidic and neutral conditions.

3.
Reprod Biol Endocrinol ; 20(1): 118, 2022 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-35964035

RESUMO

BACKGROUND: Fertility awareness and menses prediction are important for improving fecundability and health management. Previous studies have used physiological parameters, such as basal body temperature (BBT) and heart rate (HR), to predict the fertile window and menses. However, their accuracy is far from satisfactory. Additionally, few researchers have examined irregular menstruators. Thus, we aimed to develop fertile window and menstruation prediction algorithms for both regular and irregular menstruators. METHODS: This was a prospective observational cohort study conducted at the International Peace Maternity and Child Health Hospital in Shanghai, China. Participants were recruited from August 2020 to November 2020 and followed up for at least four menstrual cycles. Participants used an ear thermometer to assess BBT and wore the Huawei Band 5 to record HR. Ovarian ultrasound and serum hormone levels were used to determine the ovulation day. Menstruation was self-reported by women. We used linear mixed models to assess changes in physiological parameters and developed probability function estimation models to predict the fertile window and menses with machine learning. RESULTS: We included data from 305 and 77 qualified cycles with confirmed ovulations from 89 regular menstruators and 25 irregular menstruators, respectively. For regular menstruators, BBT and HR were significantly higher during fertile phase than follicular phase and peaked in the luteal phase (all P < 0.001). The physiological parameters of irregular menstruators followed a similar trend. Based on BBT and HR, we developed algorithms that predicted the fertile window with an accuracy of 87.46%, sensitivity of 69.30%, specificity of 92.00%, and AUC of 0.8993 and menses with an accuracy of 89.60%, sensitivity of 70.70%, and specificity of 94.30%, and AUC of 0.7849 among regular menstruators. For irregular menstruators, the accuracy, sensitivity, specificity and AUC were 72.51%, 21.00%, 82.90%, and 0.5808 respectively, for fertile window prediction and 75.90%, 36.30%, 84.40%, and 0.6759 for menses prediction. CONCLUSIONS: By combining BBT and HR recorded by the Huawei Band 5, our algorithms achieved relatively ideal performance for predicting the fertile window and menses among regular menstruators. For irregular menstruators, the algorithms showed potential feasibility but still need further investigation. TRIAL REGISTRATION: ChiCTR2000036556. Registered 24 August 2020.


Assuntos
Temperatura Corporal , Ciclo Menstrual , Algoritmos , Temperatura Corporal/fisiologia , Criança , China , Feminino , Fertilidade/fisiologia , Frequência Cardíaca , Humanos , Aprendizado de Máquina , Ciclo Menstrual/fisiologia , Gravidez , Estudos Prospectivos
4.
Artigo em Inglês | MEDLINE | ID: mdl-35682093

RESUMO

Chloramine and chloroform are widespread in tap water due to water disinfection processes. This study was designed to explore the associations between trimester-specific exposure to chloramine and chloroform in tap water and adverse outcomes. This retrospective cohort study included 109,182 mother-infant singleton pairs in Shanghai. A logistic regression model was used to evaluate the associations of chloramine and chloroform concentrations averaged over the whole pregnancy and in each trimester with adverse outcomes, including gestational diabetes mellitus (GDM), gestational hypertensive disorders (GHD), low birthweight (LBW), small for gestational age (SGA), preterm birth (PTB) and prelabor rupture of membranes (PROM). The use of tap water with elevated chloramine levels in the first trimester was associated with GDM (OR = 1.06, 95% CI: 1.03, 1.09), while that in the second trimester was related to GHD (OR = 1.13, 95% CI: 1.09, 1.17). Chloroform levels in the third trimester were associated with LBW (OR = 1.13, 95% CI: 1.09, 1.16), PTB (OR = 1.05, 95% CI: 1.01, 1.08) and PROM (OR = 1.01, 95% CI: 1.00, 1.01). However, tap water chloroform exposure in the second trimester was negatively associated with LBW (OR = 0.95, 95% CI: 0.93, 0.98) and PTB (OR = 0.97, 95% CI: 0.94, 0.99). In conclusion, there are probably no casual associations between current tap water chloroform and chloramine levels and perinatal outcomes. However, more research focusing on the effect of chloramine and chloroform on perinatal outcomes are still warranted.


Assuntos
Diabetes Gestacional , Hipertensão Induzida pela Gravidez , Nascimento Prematuro , China/epidemiologia , Cloraminas , Clorofórmio , Feminino , Humanos , Recém-Nascido , Gravidez , Resultado da Gravidez/epidemiologia , Estudos Retrospectivos , Água
5.
Angew Chem Int Ed Engl ; 61(20): e202201430, 2022 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-35253345

RESUMO

Herein, we present a stable water-soluble cobalt complex supported by a dianionic 2,2'-([2,2'-bipyridine]-6,6'-diyl)bis(propan-2-ol) ligand scaffold, which is a rare example of a high-oxidation species, as demonstrated by structural, spectroscopic and theoretical data. Electron paramagnetic resonance (EPR) spectroscopy and magnetic susceptibility measurements revealed that the CoIV center of the mononuclear complex in the solid state resides in the high spin state (sextet, S=5/2). The complex can effectively catalyze water oxidation via a single-site water nucleophilic attack pathway with an overpotential of only 360 mV in a phosphate buffer with a pH of 6. The key intermediate toward water oxidation was speculated based on theoretical calculations and was identified by in situ spectroelectrochemical experiments. The results are important regarding the accessibility of high-oxidation state metal species in synthetic models for achieving robust and reactive oxidation catalysis.


Assuntos
Cobalto , Água , Catálise , Cobalto/química , Espectroscopia de Ressonância de Spin Eletrônica , Oxirredução , Água/química
6.
Gynecol Endocrinol ; 36(10): 890-894, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32208782

RESUMO

We design this study to detect levels of Elabela (ELA) and Apelin (APLN) in women with and without gestational diabetes mellitus (GDM) in the second and third trimesters, and to identify whether there is any association between ELA, APLN, and metabolic parameters. Seventy-nine GDM and 80 control subjects in the second trimester and 87 GDM and 88 healthy subjects in the third trimester were included. In the second trimester, lower ELA levels [(14.1 versus 16.9) ng/ml, p = .025] and higher APLN levels [(1021.8 versus 923.5) pg/ml, p = .046] were observed in GDM patients compared to controls. ELA levels were positively correlated with fasting plasma glucose (FPG) (r = 0.423, p < .001) in the control group, and APLN levels were negatively correlated with triglycerides (TG) (r = -0.251, p = .025) in the control group and total cholesterol (TC) (r = -0.227, p = .044) in the GDM group. ELA appeared to be related to glucose metabolism and APLN is involved in lipid metabolism during pregnancy. The expression of ELA is significantly downregulated from the second trimester to the third trimester.


Assuntos
Apelina/sangue , Diabetes Gestacional/sangue , Hormônios Peptídicos/sangue , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Gravidez , Segundo Trimestre da Gravidez/sangue , Terceiro Trimestre da Gravidez/sangue
7.
Thromb Res ; 187: 63-71, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31958688

RESUMO

INTRODUCTION: Assisted reproductive technology (ART) treatment is a risk factor for pregnancy-related venous thromboembolism (VTE). This study aims to explore the risk factors for elevated fibrin (fibrinogen) degradation products (FDPs), an indicator of hypercoagulability, in late pregnancy among women who underwent ART treatment. MATERIALS AND METHODS: This retrospective case-control study recruited 227 women who spontaneously conceived and 214 women who underwent ART treatment and gave birth. A subgroup analysis of the 214 pregnant women after ART treatment was performed. 156 women with elevated FDP levels and 58 women with normal FDP levels were designated as the case and control groups, respectively. RESULTS: We found that ART treatment was a risk factor for higher FDP. After adjustments were made for confounders in the group of 214 women after ART treatment, fresh embryo transfer (adjusted odds ratio (aOR) = 3.33, 95% confidence interval (CI), 1.57-7.03) and >10 oocytes retrieved (aOR = 2.09, 95% CI, 1.10-3.99) were associated with elevated FDP in late pregnancy. Serum estradiol (E2) levels on human chorionic gonadotropin (hCG) trigger day were higher in the high-FDP group. A positive correlation between E2 on hCG trigger day and FDP was found for both fresh embryo transfer (r = 0.67, p < 0.001) and frozen embryo transfer (FET) (r = 0.53, p < 0.001). CONCLUSIONS: A higher E2 level on hCG trigger day is closely associated with dysfunction of coagulation and fibrinolysis in late pregnancy. When performing the thromboprophylaxis assessment during pregnancy, clinicians should pay more attention to patients who had previous ART treatment and had a high E2 level on hCG trigger day.


Assuntos
Produtos de Degradação da Fibrina e do Fibrinogênio , Tromboembolia Venosa , Anticoagulantes , Estudos de Casos e Controles , Estradiol , Feminino , Fertilização in vitro , Humanos , Indução da Ovulação , Gravidez , Técnicas de Reprodução Assistida , Estudos Retrospectivos
8.
J Dev Orig Health Dis ; 11(4): 392-402, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31679538

RESUMO

Maternal supraphysiological estradiol (E2) environment during pregnancy leads to adverse perinatal outcomes. However, the influence of oocyte exposure to high E2 levels on perinatal outcomes remains unknown. Thus, a retrospective cohort study was conducted to explore the effect of high E2 level induced by controlled ovarian stimulation (COH) on further outcomes after frozen embryo transfer (FET). The study included all FET cycles (n = 10,581) between 2014 and 2017. All cycles were categorized into three groups according to the E2 level on the day of the human Chorionic Gonadotropin trigger. Odds ratios (ORs) and their confidence intervals (CIs) were calculated to evaluate the association between E2 level during COH and pregnancy outcomes and subsequent neonatal outcomes. From our findings, higher E2 level was associated with lower percentage of chemical pregnancy, clinical pregnancy, ongoing pregnancy, and live birth as well as increased frequency of early miscarriage. Preterm births were more common among singletons in women with higher E2 level during COH (aOR1 = 1.93, 95% CI: 1.22-3.06; aOR2 = 2.05, 95% CI: 1.33-3.06). Incidence of small for gestational age (SGA) was more common in both singletons (aOR1 = 2.01, 95% CI: 1.30-3.11; aOR2 = 2.51, 95% CI: 1.69-3.74) and multiples (aOR1 = 1.58, 95% CI: 1.03-2.45; aOR2 = 1.99, 95% CI: 1.05-3.84) among women with relatively higher E2 level. No association was found between high E2 level during COH and the percentage of macrosomia or large for gestational age. In summary, oocyte exposure to high E2 level during COH should be brought to our attention, since the pregnancy rate decreasing and the risk of preterm birth and SGA increasing following FET.


Assuntos
Peso ao Nascer , Estradiol/efeitos adversos , Macrossomia Fetal/epidemiologia , Recém-Nascido Pequeno para a Idade Gestacional/crescimento & desenvolvimento , Oócitos/efeitos dos fármacos , Indução da Ovulação/métodos , Nascimento Prematuro/epidemiologia , Adulto , China/epidemiologia , Transferência Embrionária , Estradiol/administração & dosagem , Estrogênios/administração & dosagem , Estrogênios/efeitos adversos , Feminino , Macrossomia Fetal/induzido quimicamente , Idade Gestacional , Humanos , Recém-Nascido , Nascido Vivo/epidemiologia , Masculino , Oócitos/patologia , Gravidez , Resultado da Gravidez , Nascimento Prematuro/induzido quimicamente , Estudos Retrospectivos
9.
BMC Med ; 16(1): 96, 2018 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-29914496

RESUMO

BACKGROUND: Despite limited information on neonatal safety, the transfer of frozen-thawed cleavage-stage embryos with blastomere loss is common in women undergoing in vitro fertilization. We aimed to evaluate the pregnancy outcomes and safety of frozen-thawed cleavage-stage embryos with blastomere loss. METHODS: This prospective, multicenter, cohort study included all frozen-thawed cleavage-stage embryo transfer (FET) cycles between 2002 and 2012. Pregnancy outcomes and subsequent neonatal outcomes were compared between FET cycles with intact embryos and those with blastomere loss. RESULTS: A total of 12,105 FET cycles were included in the analysis (2259 cycles in the blastomere loss group and 9846 cycles in the intact embryo group). The blastomere loss group showed significantly poorer outcomes with respect to implantation, pregnancy, and live birth rates than the intact embryo group. However, following embryo implantation, the two groups were similar with respect to live birth rates per clinical pregnancy. Among multiple pregnancies (4229 neonates), neonates from the blastomere loss group were at an increased risk of being small for gestational age (aOR = 1.50, 95% CI 1.00-2.25) compared to those from the intact group. A similar trend was observed among singletons (aOR = 1.84, 95% CI 0.99-3.37). No associations were found between blastomere loss and the subsequent occurrence of congenital anomalies or neonatal mortality. However, neonates from the blastomere loss group were at an increased risk of transient tachypnea of the newborn (aOR = 5.21, 95% CI 2.42-11.22). CONCLUSIONS: The transfer of embryos with blastomere loss is associated with reduced conception rates. Once the damaged embryos have implanted, pregnancies appear to have the same probability of progressing to live birth but with an increased risk of small for gestational age neonates and transient tachypnea of the newborn. STUDY REGISTRATION: This study was retrospectively registered at Chinese Clinical Trial Registry. Registration number: ChiCTR-OOC-16007753 . Registration date: 13 January 2016.


Assuntos
Blastômeros/metabolismo , Implantação do Embrião/fisiologia , Transferência Embrionária/métodos , Fertilização in vitro/métodos , Adulto , Blastômeros/citologia , Estudos de Coortes , Feminino , Humanos , Recém-Nascido , Gravidez , Resultado da Gravidez , Estudos Prospectivos
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