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A critical constraint impeding the utilization of Mn-based oxide catalysts in NH3 selective catalytic reduction (NH3-SCR) is their inadequate resistance to water and sulfur. This vulnerability primarily arises from the propensity of SO2 to bind to the acidic site in manganese oxide, resulting in the formation of metal sulfate and leading to the irreversible deactivation of the catalyst. Therefore, gaining a comprehensive understanding of the detrimental impact of SO2 on the acidic sites and elucidating the underlying mechanism of this toxicity are of paramount importance for the effective application of Mn-based catalysts in NH3-SCR. Herein, we strategically modulate the acidity of the manganese oxide catalyst surface through the incorporation of Ce and Nb. Comprehensive analyses, including thermogravimetry, NH3 temperature-programmed desorption, in situ diffused reflectance infrared Fourier transform spectroscopy, and density functional theory calculations, reveal that SO2 exhibits a propensity for adsorption at strongly acidic sites. This mechanistic understanding underscores the pivotal role of surface acidity in governing the sulfur resistance of manganese oxide.
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High-entropy oxides (HEOs) exhibit abundant structural diversity due to cationic and anionic sublattices with independence, rendering them superior in catalytic applications compared to monometallic oxides. Nevertheless, the conventional high-temperature calcination approach undermines the porosity and reduces the exposure of active sites (such as oxygen vacancies, OVs) in HEOs, leading to diminished catalytic efficiency. Herein, we fabricate a series of HEOs with a large surface area utilizing a microenvironment modulation strategy (m-NiMgCuZnCo: 86 m2/g, m-MnCuCoNiFe: 67 m2/g, and m-FeCrCoNiMn: 54 m2/g). The enhanced porosity in m-NiMgCuZnCo facilitates the presentation of numerous OVs, exhibiting an exceptional catalytic performance. This tactic creates inspiration for designing HEOs with rich porosity and active species with vast potential applications.
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Hierarchical porosity of carbonates can facilitate their performance in massive applications as compared to their corresponding bulk samples. Traditional solution-based precipitation is typically utilized to fabricate porous carbonates. However, this tactic is generally employed under humid conditions, which demand soluble metal precursors, solvents, and extended dry periods. A salt-assisted mechanochemistry is exploited in contemporary work to settle the shortcomings. Enlighted by solid-state technology, this approach eliminates the utilization of solvents, and the process of ball milling can create pores in 5 min. A range of highly porous carbonates and their derivatives are acquired, with several materials surpassing recording surface areas (e.g., H-CaCO3: 108 m2/g, SrCO3: 125 m2/g, BaCO3: 172 m2/g, Pd/H-CaCO3 catalyst: 101 m2/g). The results display that Pd/H-CaCO3 shows superior catalytic efficiency in the synthesis of aniline (turnover frequency [TON] = 1.33 × 104/h-1, yield ≥ 99%, and recycle stability: 11 cycles) and dye degradation. Combining mechanochemistry and salt-assisted tactic provides a facile and efficient pathway for processing porous materials.
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In this paper, a flexible ultrawideband metamaterial absorber (MMA) with multiple perfect absorption peaks has been proposed and investigated. In this design, we choose the rubber as the dielectric layer to achieve flexibility and select the split square ring to reach multiple perfect absorbing peaks. For the simulation results, the three-layer absorber that reaches 90% absorptivity has achieved 3.87 to 10.84 GHz. Then, we propose a five-layer absorber for easy facilitation, whose absorptivity reaching 90% has achieved 3.78 to 9.85 GHz, and the absorption peak has reached 99.99%, 100%, 100%, and 99.99% at 4, 5.82, 8.46, and 9.71 GHz, respectively.
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Carbon disulfide (CS2) exposure can cause embryo implantation loss but the mechanism remains unclear. Earlier study revealed that the 4th day of gestation (GD4) and GD5 were the most sensitive exposure time on which the number of implanted embryos decreased obviously in mice. Leukemia inhibitory factor (LIF) in maternal uterine tissue is involved in embryo implantation, which is produced by endometrium and Th2 cells that participate in cellular adhesion of maternal-fetal interface. We herein investigated the effect of CS2 on the expression of LIF in uterine tissue and its regulatory mechanism in Kunming mice. Exposure was on GD3, GD4, GD5 and GD6, respectively, single administration (631.4 mg/kg), and the indexes were arranged in time series after exposure. The results showed that LIF gene breakage was captured at the 18th hour after exposure by Comet-FISH and the protein and mRNA of LIF in uterine tissue were down-regulated after exposure through the peri-implantation period. In addition, sex steroid hormones, progesterone (P4) and oestrogen (E2) were detected since they can stimulate synthesis of LIF from endometrial cells. Results showed that P4 and E2 in serum were down-regulated at all the endpoints of CS2 exposure groups. These findings suggested that the down-regulated LIF induced by the decreased P4 and E2 after mice exposure to CS2 might be important reasons for implantation disorders.
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Dissulfeto de Carbono/toxicidade , Perda do Embrião/induzido quimicamente , Fator Inibidor de Leucemia/genética , Fator Inibidor de Leucemia/metabolismo , Útero/efeitos dos fármacos , Útero/metabolismo , Animais , Ensaio Cometa , Dano ao DNA , Regulação para Baixo/efeitos dos fármacos , Implantação do Embrião/efeitos dos fármacos , Implantação do Embrião/genética , Implantação do Embrião/fisiologia , Perda do Embrião/genética , Perda do Embrião/metabolismo , Estradiol/sangue , Feminino , Idade Gestacional , Hibridização in Situ Fluorescente , Camundongos , Gravidez , Progesterona/sangue , RNA Mensageiro/genética , RNA Mensageiro/metabolismoRESUMO
Laser processing is an efficient method for fabricating a superhydrophobic surface and has attracted much attention due to its multifunctionality. However, excessive laser processing, such as laser beam overlap and multiple scans, generates both a thick, brittle recast layer and a thin material thickness, thereby greatly reducing the mechanical strength of the substrate. In addition, there is no report on fabricating a superhydrophobic surface on a superalloy substrate whose application includes a self-cleaning property. This work proposes the fabrication of a superhydrophobic surface on a superalloy substrate with high mechanical strength by optimizing the laser processing parameters including laser power, scanning speed, line spacing, and number of scans. We found that the microstructures required by superhydrophobicity could be constructed with a single laser scan. which could guarantee a minimal loss of the mechanical strength. The fabricated superhydrophobic surface on the superalloy substrate exhibited excellent self-cleaning of carbon deposition, showing good application potential in the aero engine field.
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This work presents an efficient sorbent for plant growth regulators (PGRs) by regulating the defects of a metal-organic framework MIL-101(Cr). Using the regulated MIL-101(Cr), we developed a simple and effective method for the simultaneous determination of eleven PGRs in fresh fruit juice. The extraction conditions were optimized by an orthogonal array design. Under optimal conditions, the method showed a satisfactory limit of detection (0.1-1.2 ng/g), recovery rates (83.4-110.2 %), and precision (2.9-18.0 % for intra-day and 2.7-10.8 % for inter-day), as well as a greatly suppressed matrix effect. Notably, regulating the defects significantly enhanced the desorption of PGRs on MIL-101(Cr). The sorbent didn't need to be destroyed to release the adsorbed PGRs and could be reused at least 6 times. Furthermore, the defects of MIL-101(Cr) and interactions between the sorbent and PGRs were studied by TGA, ATR-IR, XPS, NH3-TPD and UV-Vis DRS.
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Estruturas Metalorgânicas , Reguladores de Crescimento de Plantas/análise , Sucos de Frutas e Vegetais , Cromatografia Líquida de Alta Pressão/métodos , Extração em Fase Sólida/métodosRESUMO
Carbon disulfide (CS2) may lead to spontaneous abortion and very early pregnancy loss in women exposed in the workplace, but the mechanism remains unclear. We designed an animal model in which gestating Kunming strain mice were exposed to CS2 via i.p. on gestational day 4 (GD4). We found that the number of implanted blastocysts on GD8 was significantly reduced by each dose of 0.1 LD50 (157.85 mg/kg), 0.2 LD50 (315.7 mg/kg) and 0.4 LD50 (631.4 mg/kg). In addition, both the level of DNA damage and apoptosis rates of endometrial cells on GD4.5 were increased, showed definite dose-response relationships, and inversely related to the number of implanted blastocysts. The expressions of mRNA and protein for the Bax and caspase-3 genes in the uterine tissues on GD4.5 were up-regulated, while the expressions of mRNA and protein for the Bcl-2 gene were dose-dependently down-regulated. Our results indicated that DNA damage and apoptosis of endometrial cells were important reasons for the loss of implanted blastocysts induced by CS2.
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Apoptose/fisiologia , Dissulfeto de Carbono/toxicidade , Dano ao DNA/fisiologia , Perda do Embrião/induzido quimicamente , Perda do Embrião/patologia , Endométrio/patologia , Animais , Apoptose/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Endométrio/efeitos dos fármacos , Feminino , Camundongos , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/patologia , Distribuição AleatóriaRESUMO
OBJECTIVE: To evaluate the effects of carbon disulfide (CS(2)) exposure during peri-implantation on the estrogen receptor-α (ER-α) expression in the uterus and serum level of estradiol (E(2)) in pregnant mice, and to explore the mechanism of embryotoxicity of CS(2). METHODS: Healthy female mice were exposed to a single dose of CS(2) (631.4 mg/kg) or olive oil (solvent control) on gestational day (GD)3, GD4, GD5, or GD6. At different time points after exposure, the serum E(2) levels of the pregnant mice were measured by enzyme-linked immunosorbent assay, and the expression levels of ER-α in the uterus were measured by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blot. RESULTS: Compared with the control group, the GD3, GD4, GD5, and GD6 exposure groups showed significantly decreased serum E(2) levels on day 7 of gestation (P < 0.05); the GD3 and GD5 exposure groups showed significantly decreased serum E(2) levels on day 6 of gestation (P < 0.05). The expression level of ER-α in the GD 4 exposure group was 23.6% lower than that in the control group on day 5 of gestation, and the expression level of ER-α in the GD 5 exposure group was 72.9% lower than that in the control group on day 6 of gestation (P < 0.05); the GD 3 and GD 6 exposure groups showed lower expression levels of ER-α than the control group at any time point, but no significant difference was found (P > 0.05). CONCLUSION: CS(2) exposure during peri-implantation can reduce the ER-α expression in the uterus and the serum level of E(2) in pregnant mice, which may be one of the mechanisms of embryotoxicity of CS(2).
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Dissulfeto de Carbono/toxicidade , Implantação do Embrião , Estradiol/sangue , Receptor alfa de Estrogênio/metabolismo , Útero/metabolismo , Animais , Feminino , Camundongos , Camundongos Endogâmicos , Gravidez , Útero/efeitos dos fármacosRESUMO
OBJECTIVE: To investigate the DNA damage of splenic lymphocytes in pregnant mice exposed to carbon disulfide (CS2) in the implantation phase and to explore the mechanism of abnormal implantation induced by CS2 from the perspective of immune injury. METHODS: Mice were exposed to CS2 at different doses or at different time points in the implantation phase to establish model 1 and model 2. For model 1, mice were assigned to four groups to receive a single intraperitoneal injection of low-dose CS2 (0.1 LD50, 157.8 mg/kg), middle-dose CS2 (0.2 LD50, 315.7 mg/kg), and high-dose CS2 (0.4 LD50, 631.4 mg/kg) as well as an equal volume of olive oil (control) on gestational day (GD) 4. For model 2, mice were assigned to four groups to receive a single intraperitoneal injection of CS2 (0.4 LD50, 631.4 mg/kg) or an equal volume of olive oil (control) on GD3, GD4, GD5, and GD6. At the end, single cell suspension of splenic lymphocytes was prepared. Cell viability was measured by trypan blue staining, and the DNA damage of splenic lymphocytes was evaluated by alkaline single cell gel electrophoresis assay. RESULTS: The middle-dose and high-dose exposure groups showed significantly more DNA damage of splenic lymphocytes than the control group (P < 0.01); there was significant regression relationship between indicators of DNA damage and exposure doses (P < 0.01). The GD3, GD4, GD5, and GD 6 exposure groups showed significantly more DNA damage of splenic lymphocytes than the control group (P < 0.01), and the GD 4 exposure group had the most DNA damage. CONCLUSION: Exposure to CS2 in the implantation phase can induce DNA damage of splenic lymphocytes in pregnant mice, and the DNA damage was aggravated with the increase in CS2 concentration. GD4 may be the sensitive time point for DNA damage of splenic lymphocytes induced by CS2 in pregnant mice.
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Dissulfeto de Carbono/toxicidade , Dano ao DNA/efeitos dos fármacos , Implantação do Embrião , Linfócitos/efeitos dos fármacos , Animais , Feminino , Camundongos , Gravidez , Baço/citologiaRESUMO
High-entropy oxides (HEOs) are crucial in various fields (power storage/conversion, electronic devices, and catalysis) owing to their adjustable structural characteristics, fabulous stability, and massive components. However, the current strategies for synthesizing HEOs suffer from low surface area and limited active sites. Herein, we present a salt-assisted strategy with remarkable universality for the preparation of HEOs with high surface area [e.g., HP-(FeCrCoNiCu)xOy: 59 m2/g, HP-(ZnMgNiCuCo)xOy: 49 m2/g, and HP-(CrMnFeNiZn)xOy: 11 m2/g], where HP means high porosity. Especially, HP-(FeCrCoNiCu)xOy with rich-oxygen vacancies promotes catalytic efficiency for hydrocarbon and alcohol oxidation owing to its hierarchical texture and massive oxygen vacancies. Furthermore, density functional theory is utilized to well illustrate the relationship of the structure and catalytic efficiency within the catalysts. This work offers realistic pathway for the large-scale application of HEOs in catalytic areas.
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The existence of the blood-brain barrier (BBB) and the complex inflammatory environment in the brain are two major obstacles in the treatment of Parkinson's disease (PD). As a target group, we modified the red blood cell membrane (RBCM) on the surface of upconversion nanoparticles (UCNPs) in this study to effectively target the brain. Mesoporous silicon, coated with UCNPs (UCM), was loaded with S-nitrosoglutathione (GSNO) as the nitric oxide (NO) donor. Then, UCNPs were excited to emit green light (540 nm) by 980 nm near-infrared (NIR). In addition, it produced a light-responsive anti-inflammatory effect by promoting the release of NO from GSNO and lowering the brain's level of proinflammatory factors. A series of experiments demonstrated that this strategy could effectively mitigate the inflammatory response damage of neurons in the brain.
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Nanopartículas , Doença de Parkinson , Humanos , Fármacos Fotossensibilizantes , Óxido Nítrico , Doença de Parkinson/tratamento farmacológico , Biomimética , Doadores de Óxido Nítrico/farmacologia , Doadores de Óxido Nítrico/uso terapêuticoRESUMO
OBJECTIVE: To conduct a systematic review with meta-analysis of studies assessing the association of vitamin A (retinol, carotene and other carotenoids) intake or blood (serum or plasma) levels of vitamin A (retinol and carotene) with risk of cervical cancer. METHODS: We evaluated the studies published in English and Chinese on diet or blood vitamin A for the risk of cervical cancer. We also reviewed reference lists from retrieved articles. Meta-analysis was applied to calculate the combined effect values and their 95% confidence intervals. The risk of bias was assessed by the Egger regression asymmetry test. RESULTS: As many as 11 articles on dietary vitamin A and 4 articles on blood vitamin A were selected according to the eligibility criteria and were included in the meta-analysis, for a total of 12,136 participants. The pooled odds ratios (ORs) of cervical cancer were 0.59 (95% CI, 0.49-0.72) for total vitamin A intake and 0.60 (95% CI, 0.41-0.89) for blood vitamin A levels. The combined ORs of cervical cancer were 0.80 (95% CI, 0.64-1.00), 0.51 (95% CI, 0.35-0.73) and 0.60 (95% CI, 0.43-0.84) for retinol, carotene and other carotenoid intake, and 1.14 (95% CI, 0.83-1.56) and 0.48 (95% CI, 0.30-0.77) for blood retinol and carotene. CONCLUSIONS: Vitamin A intake and blood vitamin A levels were inversely associated with the risk of cervical cancer in this meta-analysis.
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Neoplasias do Colo do Útero/sangue , Vitamina A/administração & dosagem , Vitamina A/sangue , Feminino , Humanos , Fatores de RiscoRESUMO
The development of efficient heterogeneous catalysts for one-pot tandem/cascade synthesis of imines remains meaningful and challenging. Herein, we constructed an Au/MOF catalyst featured hollow and double MOF shell nanostructure. Owing to its structural merits and acid-basic nature, the as-synthesized Void|(Au)ZIF-8|ZIF-8 catalyst exhibited an enhanced synergistically catalytic performance for tandem catalytic synthesis of imines from benzyl alcohol and aniline under air atmosphere and solvent-free condition. Its 170.16 h-1 of turnover frequency (TOF) was 2.5 times higher than that of the reported catalyst with the highest TOF value.
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OBJECTIVE: This study aimed to assess the association of breastfeeding and maternal hypertension and diabetes in Beijing, China. SUBJECTS AND METHODS: A cross-sectional study was conducted in four urban communities of Beijing, China, with 9,128 parous women 40-81 years of age who had had only one lifetime birth. Each participant completed a detailed survey and accepted blood pressure measurement and blood glucose testing. Moreover, self-reported hypertension and diabetes were confirmed by review of medical records. RESULTS: After the analysis was adjusted for the potential confounders, including age, body mass index (BMI), waist to hip ratio (WHR), working status, educational level, drinking, smoking, family history of hypertension, age of menarche, menopause, oral contraceptive use, age of child-bearing, and postpartum BMI, the odd ratio (OR) of hypertension was 1.18 (95% confidence interval [CI], 1.05-1.32) for women who did not breastfeed, compared with women who did. In addition, the ORs for >0 to 6 months, >6 to 12 months, and >12 months of breastfeeding were 0.87 (95% CI, 0.76-0.99), 0.83 (95% CI, 0.68-1.00), and 0.79 (95% CI, 0.65-0.97), respectively, compared with women who did not breastfeed. With adjustment for age, WHR, working status, educational level, family history of diabetes, and postpartum BMI, women who did not breastfeed increased the risk of diabetes (OR=1.30; 95% CI, 1.11-1.53) compared with women who did. Moreover, women who breastfed for >0 to 6 months (OR=0.81; 95% CI, 0.67-0.98) and >6 to 12 months (OR=0.46; 95% CI, 0.26-0.84) had a lower risk of diabetes, compared with women who did not breastfeed. CONCLUSIONS: Chinese mothers who did not breastfeed were more likely to develop hypertension and diabetes in later life.
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Aleitamento Materno/estatística & dados numéricos , Diabetes Mellitus Tipo 2/epidemiologia , Hipertensão/epidemiologia , Mães/estatística & dados numéricos , Adulto , Idoso , Pressão Sanguínea , China/epidemiologia , Estudos Transversais , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/etiologia , Feminino , Teste de Tolerância a Glucose , Inquéritos Epidemiológicos , Humanos , Hipertensão/sangue , Hipertensão/etiologia , Pessoa de Meia-Idade , Paridade , Gravidez , Prevalência , Inquéritos e Questionários , Fatores de Tempo , Saúde da MulherRESUMO
Endothelial NO, which is synthesized by endothelial nitric oxide synthase (eNOS), has been reported to be related with the occurrence of pre-eclampsia (PE). However, the polymorphisms of eNOS (-786 T>C, 4b/a and G894T), the level of nitric oxide and the risk of PE remain unclear. Thus we performed this meta-analysis to determine the associations between them in order to predict the risk for PE and interference with PE development in the early period of antenatal care. All studies investigating the associations between PE risk and polymorphisms of eNOS, or PE risk and serum concentration of NO were reviewed. Finally, 29 studies were included, involving 11 for -786 T>C, 11 for 4b/a, and 22 for G894T polymorphisms and PE risk. In the overall analysis, -786 T>C polymorphism was found to be related with increased PE risk in the dominant model (OR=1.17, 95% CI=1.02-1.35). a allele for 4b/a suffers the high risk of PE (OR=1.46, 95% CI=1.01-2.10). In the subgroup analysis, significantly increased risk was detected among Europeans for -786 T>C polymorphism (OR=1.40, 95%CI=1.14-1.73).However, no significant association was detected for G894T polymorphism in the overall and subgroup analysis. The comprehensive evaluation of 9 available studies indicated that serum NO level was significantly decreased in case group (SMD=-0.96 umol/mL, 95%CI=-1.80, -0.12 umol/mL).Hence, we concluded that eNOS gene -786 T>C and 4b/a except for G894T polymorphisms were contributed significantly to PE risk, especially for Europeans, and a low NO concentration in serum increased the risk for PE.
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Predisposição Genética para Doença , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico/sangue , Polimorfismo Genético , Pré-Eclâmpsia/genética , População Branca/genética , Alelos , Feminino , Humanos , Óxido Nítrico Sintase Tipo III/metabolismo , Gravidez , Fatores de RiscoRESUMO
Tumor necrosis factor-α (TNF-α) gene promoter polymorphisms (-308G/A, -238G/A) have been associated with increased recurrent spontaneous abortion (RSA) risk, but the results of published articles are controversial. Hence, a meta-analysis was performed to assess the effect of TNF-α -308G/A, -238G/A polymorphisms on RSA risk. Heterogeneity testing and sensitivity analysis were performed using RevMan 5.0 software. Publication bias was assessed by the funnel plot method and modified Egger's linear regression test. In 12 studies for the TNF-α -308G/A polymorphism, the summary odds ratio (OR) with the corresponding 95% confidence interval (95% CI) was 1.04 (95% CI: 0.86, 1.26) under a fixed-effect model in the overall population. In 5 studies for the TNF-α -238G/A polymorphism, the summary OR with the corresponding 95% CI was 1.11 (95% CI: 0.60, 2.03) under a random-effect model in the overall population. We could not identify the sources of heterogeneity for TNF-α -238G/A. In addition, no evidence of publication bias was detected. The results of this meta-analysis indicate that TNF-α -308G/A, -238G/A polymorphisms are not significantly associated with the risk of RSA in the overall population. However, more convincing evidence is required to draw a solid conclusion on the relation between the TNF-α -238G/A polymorphism and the risk of RSA.
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Aborto Habitual/genética , Polimorfismo de Nucleotídeo Único , Software , Fator de Necrose Tumoral alfa/genética , Adulto , Alelos , Estudos de Casos e Controles , Feminino , Frequência do Gene , Genótipo , Humanos , Razão de Chances , Gravidez , Regiões Promotoras Genéticas , RiscoRESUMO
To evaluate the association between vascular endothelial growth factor (VEGF) gene polymorphisms and the risk of recurrent spontaneous abortion (RSA), a meta-analysis of published case-control studies for the VEGF gene polymorphisms (gene polymorphisms reported more than three times were selected) and the risk of RSA. Odds ratios (ORs) and 95% confidence intervals (CIs) for codominant, dominant and recessive genetic models were assessed by RevMan software. Eight studies with 2813 cases and 2830 controls were included in this meta-analysis. The pooled analysis showed that -2578C/A, -1154G/A polymorphisms of VEGF were not significantly associated with the risk of RSA neither under codominant model nor under dominant model, nor under recessive model. Whereas, for -634G/C polymorphism, the pooled OR and 95% CI were 1.23 (1.01-1.49) under recessive model; and for 936C/T polymorphism, the pooled OR and 95% CI were 1.34 (1.07-1.67) and 1.40 (1.09-1.80) under codominant and dominant models, respectively. This meta-analysis suggested that VEGF gene -2578C/A, -1154G/A polymorphisms were not significantly associated with the risk of RSA, whereas, -634G/C and +936C/T polymorphisms were associated with the risk of RSA under specific genetic models.