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Rapid evaluation of the toxicity of metals using fish embryo acute toxicity is facilitative to ecological risk assessment of aquatic organisms. However, this approach has seldom been utilized for the comparative study on the effects of different metals to fish. In this study, acute and sub-chronic tests were used to compare the toxicity of Se(IV) and Cd in the embryos and larvae of Japanese medaka (Oryzias latipes). The embryos with different levels of dechorionation and/or pre-exposure were also exposed to Se(IV) and Cd at various concentrations. The results showed that the LC50-144 h of Cd was 1.3-5.2 folds higher than that of Se(IV) for the embryos. In contrast, LC50-96 h of Se(IV) were 200-400 folds higher than that of Cd for the larvae. Meanwhile, dechorionated embryos were more sensitive to both Se and Cd than the intact embryos. At elevated concentrations, both Se and Cd caused mortality and deformity in the embryos and larvae. In addition, pre-exposure to Cd at the embryonic stages enhanced the resistance to Cd in the larvae. However, pre-exposure to Se(IV) at the embryonic stages did not affect the toxicity of Se(IV) to the larvae. This study has distinguished the nuance differences in effects between Se(IV) and Cd after acute and sub-chronic exposures with/without chorion. The approach might have a potential in the comparative toxicology of metals (or other pollutants) and in the assessment of their risks to aquatic ecosystems.
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Embrión no Mamífero , Larva , Oryzias , Contaminantes Químicos del Agua , Animales , Oryzias/embriología , Contaminantes Químicos del Agua/toxicidad , Larva/efectos de los fármacos , Embrión no Mamífero/efectos de los fármacos , Cadmio/toxicidad , Pruebas de Toxicidad AgudaRESUMEN
Phasing down fossil fuels is crucial for climate mitigation. Even though 80-90% of fossil fuels are used to provide energy, their use as feedstock to produce plastics, fertilizers, and chemicals, is associated with substantial CO2 emissions. However, our understanding of hard-to-abate chemical production remains limited. Here we developed a chemical process-based material flow model to investigate the non-energy use of fossil fuels and CO2 emissions in China. Results show in 2017, the chemical industry used 0.18 Gt of coal, 88.8 Mt of crude oil, and 12.9 Mt of natural gas as feedstock, constituting 5%, 15%, and 7% of China's respective total use. Coal-fed production of methanol, ammonia, and PVCs contributes to 0.27 Gt CO2 emissions ( ~ 3% of China's emissions). As China seeks to balance high CO2 emissions of coal-fed production with import dependence on oil and gas, improving energy efficiency and coupling green hydrogen emerges as attractive alternatives for decarbonization.
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Objective: To evaluate the effects of different delivery modes on pelvic floor function in parturients 6-8 weeks after delivery using transperineal four-dimensional ultrasound. Methods: Pelvic floor function 6-8 weeks after delivery in 40 vaginal delivery parturients between November 2018 and December 2020 was assessed by four-dimensional ultrasound, with 40 selective cesarean section delivery parturients as a control group. The imaging results of the two groups were compared. Results: The levels of clinical indexes such as UVJ-M, A r , A v , θ, D r , D v , and ARJ-VDv in the selective cesarean section group were significantly lower than those in the vaginal delivery group 6-8 weeks after delivery (P < 0.05). However, no significant difference in CV-VD was observed under Valsalva action and at rest between the two groups (P > 0.05). No significant difference in ARJ-VD was found at rest between the two groups (P > 0.05). The incidence of pelvic organ prolapse in the selective cesarean section group (40.0%) was significantly lower than that in the vaginal delivery group (62.5%) (P < 0.05). No significant difference in the parameters of pelvic diaphragm hiatus at rest was observed between the two groups (P > 0.05). The parameters of pelvic diaphragm hiatus under maximum Valsalva action in the vaginal delivery group were significantly higher than those in the selective cesarean section group (P < 0.05). Whether the patient was complicated with diabetes had no significant effect on the functional injury of pelvic floor muscle (P > 0.05). Conclusion: The pelvic floor function 6-8 weeks after delivery was significantly more affected in vaginal delivery than in selective cesarean section. Selective cesarean section had certain but limited protective effect on maternal pelvic floor tissue.
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Cesárea , Diafragma Pélvico , Parto Obstétrico/efectos adversos , Parto Obstétrico/métodos , Femenino , Humanos , Diafragma Pélvico/diagnóstico por imagen , Diafragma Pélvico/fisiología , Periodo Posparto , Embarazo , UltrasonografíaRESUMEN
Whether chronic exposure to environmental doses of polycyclic aromatic hydrocarbons (PAHs) can lead to neurotoxic effects is still unclear. Hence, the neurotoxic effects of perinatal and juvenile exposure to 16 priority-controlled PAHs were investigated. The mice were treated with 0, 0.5, 18.75, 50, 1875 µg/kg/day of PAHs corresponding to various population exposure concentrations from gestation to postnatal day 60. Urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) and hippocampal and cortical neurotransmitter levels were determined using liquid chromatography-tandem mass spectrometry. Typical indicators or outcome of neurotoxicity, including, spatial learning and memory ability, hippocampal long-term potentiation (LTP) and dendritic spine density were evaluated via Morris water maze tests, electrophysiological experiments and Golgi-Cox assays, respectively. The results showed that exposure to different levels of PAH could not increase oxidative DNA damage level. Mice exposed to 0.5, 50 and 1875 µg/kg/day PAHs had significantly longer escape latency than the control group only on the 1st day (p < 0.05). The number of platform crossings and the time spent in target quadrant were similar between the control and the PAHs-exposed mice. Compared with the control mice, only those exposed to 50 µg/kg/day PAHs had significantly lower LTP in hippocampal CA1 region and dendritic spine density in hippocampal DG region (p < 0.05). Except for serotonin, no significant difference in hippocampal and cortical neurotransmitter concentrations was observed between the control and PAHs-exposed groups. Taken together, perinatal and juvenile exposure to environmental doses of PAHs had no profound effect on spatial learning and memory abilities, hippocampal LTP, dendritic spines density, and neurotransmitter levels. These unexpected findings were quite different from previous in vivo studies which commonly used 2-3 orders of magnitude higher PAHs doses to treat animals. Thus, the environmental dose is a crucial reference for future toxicological research to reveal the actual toxic mechanisms and human health effects of PAHs exposure.
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Venenos , Hidrocarburos Policíclicos Aromáticos , 8-Hidroxi-2'-Desoxicoguanosina , Animales , Femenino , Ratones , Neurotransmisores , Estrés Oxidativo , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/toxicidad , EmbarazoRESUMEN
The variation of and the interrelation between different energy markets significantly affect the competitiveness of various energy technologies, therefore complicate the decision-making problem for a complex energy system consisting of multiple competing technologies, especially in a long-term time frame. The interrelations between these markets have not been accounted for in the existing energy system modelling efforts, leading to a distortion of understanding of the market impact on the technological choices and operations in the real world. This study investigates the strategic and operational decision-making problem for such an energy system characterized by three competing technologies from crude oil, natural gas, and coal. A stochastic programming model is constructed by incorporating multiple volatile energy prices interrelated with each other. Oil price is modelled by the mean-reverting Ornstein-Uhlenbeck process and serves as the exogenous variable in the ARIMAX models for natural gas and downstream plastic prices. The K-means clustering method is employed to extract a handful of distinctive patterns from a large number of simulated price projections to enhance the computing efficiency without losing retaining critical information and insights from the price co-movement. The model results suggest that the high volatility of the energy market weakens the possibility of selecting the corresponding technology. The oil-based route, for example, gradually loses its market share to the coal approach, attributed to a higher volatile oil market. The proposed method is applicable to other problems of the same kind with high-dimensional stochastic variables. Supplementary Information: The online version contains supplementary material available at 10.1007/s10479-021-04229-3.
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As the world's largest inland shipping channel, the Yangtze River Economic Belt (YREB) is strategic to China's sustainable development where policymakers are increasingly emphasizing not only this region's economic development but also its CO2 emission reduction targets. To achieve emission targets in the YREB region, it is essential to identify the driving forces of its CO2 emissions. However, existing studies are not very refined and only examine the overall effects of drivers on CO2 emission changes, while neglecting the sub-regional and sectoral level effects across China. More refined research, therefore, will provide better-targeted policies for emission reduction relevant to regional levels such as the YREB region. Towards this end, this paper integrates the methods of structural decomposition analysis and attribution analysis to demonstrate the driving forces, at both sub-regional and sectoral levels, for YREB's emission changes from 2002 to 2012. Our results reveal the following: (1) Jiangsu Province has always been the main regional source of increasing CO2 emissions in the YREB, accounting for more than 20% of total CO2 emission growth. (2) The Electricity and Heat Production and Supply sector is responsible for most of the increases in CO2 emissions, both in 2002-2007 (609.8 Mt, 54.8%) and 2007-2012 (287.6 Mt, 34%). (3) During the period of 2007-2012, changes in per capita final demand were the primary driving force for the increases in CO2 emissions, while changes in CO2 emission intensity were the largest driving force for decreasing CO2 emissions, respectively accounting for 179.9% and -119.4% of total emission changes in the YREB region. (4) Moreover, the effect of emission intensity mainly exists in the Electricity and Heat Production and Supply sector in the Jiangsu and Zhejiang provinces, accounting for respectively, 10% and 10.4% of the total effects across all economic sectors. Considering the diverse impacts of driving forces in different sub-regions and economic sectors, policymakers should apply more refined measures to utilize varying driving forces in different sub-regions and economic sectors towards sustainable development.
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Dióxido de Carbono , Ríos , Dióxido de Carbono/análisis , China , Desarrollo Económico , Factores SocioeconómicosRESUMEN
Exposure to benzo[a]pyrene (B[a]P) may be a risk factor for pulmonary diseases. To investigate the correlations among B[a]P exposure level, DNA strand breaks and pulmonary inflammation, we recruited 83 children diagnosed with pulmonary diseases and 63 healthy children from Guangzhou, China. Results showed that the levels of Benzo[a]pyrene diol epoxide (BPDE) DNA adduct in blood and IL-8 in serum in case group were significantly higher than those in control group (p < 0.01). Moreover, levels of atmospheric B[a]P in case group was about twice of those in control group, which was consistent with the levels of BPDE-DNA adduct in blood. Significant positive correlations were observed among the levels of BPDE-DNA adduct, IL-8 and DNA strand breaks (p < 0.05). Our findings indicate that environmental air is an important exposure source of B[a]P and higher B[a]P exposure may contribute to the occurrence of pulmonary inflammation and lead to high health risks.
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Aductos de ADN/sangre , Interleucina-8/sangre , Enfermedades Pulmonares/sangre , 7,8-Dihidro-7,8-dihidroxibenzo(a)pireno 9,10-óxido , Adolescente , Contaminantes Atmosféricos/análisis , Contaminantes Atmosféricos/orina , Monitoreo Biológico , Niño , Preescolar , China , Ensayo Cometa , Roturas del ADN , Femenino , Humanos , Enfermedades Pulmonares/genética , Linfocitos , Masculino , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/orina , Medición de RiesgoRESUMEN
As previous studies found that the direct associations between urinary polycyclic aromatic hydrocarbon (PAH), benzene and toluene (BT) metabolites and the decreased lung function were not conclusive, we further investigated relationship of oxidative damage and airway inflammation induced by PAHs and BTs exposure with lung function. A total of 262 children diagnosed with asthma and 72 heathy children were recruited. Results showed that asthmatic children had higher levels of PAHs and BTs exposure, as well as Malonaldehyde (MDA) and 8-hydroxy-2'-deoxyguanosine (8-OHdG) compared with healthy children. Furthermore, binary logistic regression showed that each unit increases in level of urinary 2-&3-hydroxyfluorene (2-&3-OHF), 2-hydroxyphenanthrene (2-OHPhe), 1-hydroxyphenanthrene (1-OHP) and S-phenylmercapturic acid (S-PMA) were significantly associated with an elevated risk of asthma in children with odds ratios of 1.5, 2.3, 1.7 and 1.4, respectively, suggesting that PAHs and BTs exposure could increase the risk of asthma for children. Neither PAH nor BT metabolite could comprehensively indicate the decreased lung function as only 2-&3-OHF and 1-OHP were significantly and negatively correlated with forced vital capacity (FVC). Moreover, levels of most individual PAH and BT metabolite were significantly correlated to MDA and 8-OHdG. Further hierarchical regression analysis indicated that MDA and 8-OHdG levels did not show significant effects on the decreased lung function, suggesting that they are not the suitable biomarkers to indirectly indicate the altered lung function induced by PAHs and BTs. Urinary 2-OHPhe and 1-&9-hydroxyphenanthrene (1-&9-OHPhe) were significantly correlated with fractional exhaled nitric oxide (FeNO). Moreover, FeNO significantly contributed to decreased lung function and explained 7.7% of variance in ratio of forced expiratory volume in 1 s (FEV1) and FVC (FEV1/FVC%). Hence, FeNO, rather than oxidative damage indicators or any urinary PAH and BT metabolite, is more sensitive to indirectly reflect the decreased lung function induced by PAHs and BTs exposure for asthmatic children.
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Asma , Hidrocarburos Policíclicos Aromáticos , Benceno , Biomarcadores , Niño , Humanos , Inflamación , Estrés Oxidativo , ToluenoRESUMEN
High-income countries often outsource material demands to poorer countries along with the associated environmental damage. This phenomenon can also occur within (large) countries, such as China, which was responsible for 24 to 30% of the global material footprint (MF) between 2007 and 2010. Understanding the distribution and development of China's MF is hence critical for resource efficiency and circular economy ambitions globally. Here we present a comprehensive analysis of China's MF at the provincial and sectoral levels. We combine provincial-level input-output data with sector- and province-specific trade data, detailed material extraction data, and the global input-output database EXIOBASE. We find that some provinces have MFs equivalent to medium-sized, high-income countries and limited evidence of material decoupling. Lower-income regions with high levels of material extraction can have an MF per capita as large as developed provinces due to much higher material intensities. The higher-income south-coastal provinces have lower MF per capita than equally developed provinces. This finding relates partly to differences in economic structure but indicates the potential for improvement across provinces. Investment via capital formation is up to 4 times more resource-intensive than consumption and drives 49 to 86% of provincial-level MFs (the Organisation for Economic Co-operation and Development average is 37%). Resource-efficient production, efficient use of capital goods/infrastructure, and circular design are essential for reductions in China's MF. Policy efforts to shift to a high-quality development model may reduce material intensities, preferably while avoiding the further outsourcing of high-intensity activities to other provinces or lower-income countries.
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OBJECTIVE: To compare the clinical efficacy of nasal intermittent positive pressure ventilation (NIPPV) and heated humidified high flow nasal cannula (HHHFNC) in the treatment of respiratory distress syndrome (RDS) among very low birth weight (VLBW) preterm infants. METHODS: A total of 89 very low birth weight premature infants with respiratory distress syndrome (RDS) who were randomly administered with NIPPV (n=46) and HHHFNC (n=43) as an initial respiratory support. The incidence of initial treatment failure, the usage of pulmonary surfactant (PS), the parameters of respiratory support treatment and the incidence of complications were compared between the two groups. RESULTS: There were no significant differences between the NIPPV and HHHFNC groups in the following items: the rate of intubation within 72 hours, rate of PS use, duration of invasive or non-invasive mechanical ventilation, duration of oxygen therapy, and incidence rates of severe apnea and pneumonia (P>0.05). There were also no significant differences in the incidence rates of bronchopulmonary dysplasia, necrotizing enterocolitis, retinopathy of prematurity, patent ductus arteriosus, intracranial hemorrhage, and air leak between the two group (P>0.05). The incidence rate of nose injury in the NIPPV group was higher than that in the HHHFNC group (P<0.05). CONCLUSIONS: As an initial respiratory support for very low birth weight preterm infants with RDS, HHHFNC has a similar clinical effect as NIPPV, suggesting that HHHFNC is a safe and effective clinical option as a non-invasive ventilation treatment.
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Ventilación con Presión Positiva Intermitente/métodos , Ventilación no Invasiva/métodos , Síndrome de Dificultad Respiratoria del Recién Nacido/terapia , Femenino , Humanos , Recién Nacido , Recién Nacido de muy Bajo Peso , Ventilación con Presión Positiva Intermitente/efectos adversos , Masculino , Ventilación no Invasiva/efectos adversos , Terapia RespiratoriaRESUMEN
BACKGROUND: Amnestic mild cognitive impairment (aMCI) is characterized by cognitive functional decline, especially in memory. Resting-state functional magnetic resonance imaging (fMRI) has been widely used in neuroimaging studies that explore alterations between patients and normal individuals to elucidate the pathological mechanisms of different diseases. The current study was performed to investigate alterations in the functional connectivity of the default mode network (DMN) in aMCI patients compared to healthy elderly controls, as well as further define the association between neurological alterations and memory function. METHODS: Twenty-five aMCI patients and 25 healthy individuals were recruited and underwent both fMRI and neuropsychological examinations. fMRI data was analyzed by independent component analysis. RESULTS: Compared to healthy individuals, aMCI patients exhibited a significant increase in functional connectivity between the DMN and right-middle and right-superior frontal gyri, left-middle occipital gyrus, and left-middle temporal gyrus, but reduced functional connectivity between the DMN and left-middle and left-inferior frontal gyri and left insula. These alterations were found to be associated with reduced memory function. CONCLUSIONS: aMCI patients exhibited abnormal functional connectivity between the DMN and certain brain regions which is associated with changes in memory function associated with aMCI.
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Amnesia/diagnóstico por imagen , Disfunción Cognitiva/diagnóstico por imagen , Neuroimagen Funcional/métodos , Imagen por Resonancia Magnética/métodos , Anciano , Amnesia/psicología , Estudios de Casos y Controles , Disfunción Cognitiva/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas NeuropsicológicasRESUMEN
BACKGROUND: Cognitive impairments are highly prevalent in stroke survivors and can substantially affect their physical rehabilitation and quality of life. The management of these impairments currently remains limited, but increasing studies reported the effect of aerobic exercise on cognitive performance in patients suffering from stroke. The purpose of this review was to assess the effects of aerobic exercise on cognitive function following stroke. METHODS: Seven electronic databases (China National Knowledge Infrastructure [CNKI], Chinese Science and Technology Periodical Database [VIP], Wanfang, China Biology Medicine disc [CBM], Science Citation Index [SCI], EMBASE, and PubMed) were searched from their inception to May 31, 2015, for the effects of aerobic exercise on cognitive ability compared to usual physical activity in stroke survivors. RevMan V5.3 (The Nordic Cochrane Centre) was used to analyze the data and to evaluate the methodological quality of the included studies. RESULTS: Ten eligible studies including 394 participants were identified. Six studies showed that aerobic exercise significantly improved global cognitive ability in stroke survivors. Four studies reported aerobic exercise to be beneficial in improving memory, but only one showed statistical significance. Two studies investigated the effects of aerobic exercise on attention, and one showed a significant improvement. One study reported a significant benefit of aerobic exercise on visuospatial ability in stroke survivors. No adverse events were reported in the included studies. CONCLUSIONS: Aerobic exercise may have a positive effect on improving global cognitive ability and a potential benefit on memory, attention, and the visuospatial domain of cognition in stroke survivors. However, further large, rigorously designed trials are needed to confirm these findings.
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Trastornos del Conocimiento/terapia , Cognición , Terapia por Ejercicio , Rehabilitación de Accidente Cerebrovascular/métodos , Accidente Cerebrovascular/terapia , Atención , Trastornos del Conocimiento/diagnóstico , Trastornos del Conocimiento/fisiopatología , Trastornos del Conocimiento/psicología , Humanos , Memoria , Recuperación de la Función , Percepción Espacial , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/fisiopatología , Accidente Cerebrovascular/psicología , Resultado del Tratamiento , Percepción VisualRESUMEN
INTRODUCTION: Mild cognitive impairment (MCI) is an intermediate stage between the cognitive changes of normal aging and dementia characterised by a reduction in memory and/or other cognitive processes. An increasing number of studies have indicated that regular physical activity/exercise may have beneficial association with cognitive function of older adults with or without cognitive impairment. As a traditional Chinese Qigong exercise, Baduanjin may be even more beneficial in promoting cognitive ability in older adults with MCI, but the evidence is still insufficient. The main purpose of this study is to investigate the effect of Baduanjin exercise on neuropsychological outcomes of community-dwelling older adults with MCI, and to explore its mechanism of action from neuroimaging based on functional MRI (fMRI) and cerebrovascular function. METHODS AND ANALYSIS: The design of this study is a randomised, controlled trial with three parallel groups in a 1:1:1 allocation ratio with allocation concealment and assessor blinding. A total of 135 participants will be enrolled and randomised to the 24-week Baduanjin exercise intervention, 24-week brisk walking intervention and 24-week usual physical activity control group. Global cognitive function and the specific domains of cognition (memory, processing speed, executive function, attention and verbal learning and memory) will be assessed at baseline and 9, 17, 25 and 37â weeks after randomisation, while the structure and function of brain regions related to cognitive function and haemodynamic variables of the brain will be measured by fMRI and transcranial Doppler, respectively, at baseline and 25 and 37â weeks after randomisation. ETHICS AND DISSEMINATION: Ethics approval was given by the Medical Ethics Committee of the Second People's Hospital of Fujian Province (approval number 2014-KL045-02). The findings will be disseminated through peer-reviewed publications and at scientific conferences. TRIAL REGISTRATION NUMBER: ChiCTR-ICR-15005795; Pre-results.
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Circulación Cerebrovascular/fisiología , Disfunción Cognitiva/prevención & control , Función Ejecutiva/fisiología , Terapia por Ejercicio , Imagen por Resonancia Magnética , Prevención Primaria , Factores de Edad , Anciano , Protocolos Clínicos , Disfunción Cognitiva/fisiopatología , Femenino , Humanos , Masculino , Salud Mental , Persona de Mediana Edad , Pruebas Neuropsicológicas , Aptitud Física/fisiología , Prevención Primaria/métodos , Resultado del TratamientoRESUMEN
OBJECTIVE: To evaluate the effect of aerobic exercise on cognitive function in people with mild cognitive impairment (MCI). DESIGN: Systematic review and meta-analysis of aerobic exercise intervention for cognitive function in older adults with MCI. DATA SOURCES: PubMed, EMBASE, SinoMed, China National Knowledge Infrastructure (CNKI), Wanfang and Chinese Science and Technology Periodical (VIP) databases from their inception to 31 January 2015, the Cochrane Central Register of Controlled Trials (Cochrane Library, 2015, Issue 3) and the reference lists of all retrieved articles. ELIGIBILITY CRITERIA: Randomised controlled trials, older adults with MCI, aerobic exercises compared with no specific exercise intervention for global cognitive ability and any specific domains of cognition. DATA SYNTHESIS: Meta-analysis was conducted with RevMan V.5.3 software using the fixed-effect model for the available data without significant heterogeneity, or the random-effect model was used if appropriate. RESULTS: 11 studies were identified involving 1497 participants. Meta-analysis showed that aerobic exercise significantly improved global cognitive ability (Mini-Mental State Examination (MMSE) scores: MD=0.98, 95% CI 0.5 to 1.45, p<0.0001; Montreal Cognitive Assessment (MoCA) scores: MD=2.7, 95% CI 1.11 to 4.29, p=0.0009); weakly, positively improve memory (immediately recall: SMD=0.29, 95% CI 0.13 to 0.46, p=0.0005; delay recall: SMD=0.22, 95% CI 0.09 to 0.34, p=0.0005). No significant improvement was found in other domains of cognition. CONCLUSIONS: Aerobic exercise led to an improvement in global cognitive ability and had a positive effect with a small effect size on memory in people with MCI. However, owing to the limitations of the included studies, these findings should be interpreted cautiously.