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1.
J Sci Food Agric ; 104(5): 2704-2717, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-37997448

RESUMO

BACKGROUND: Developing the stable and healthy emulsion-based food is in accord with the needs of people for health. In the present study, acidification at pH 3.0 of peanut polysaccharide (APPSI) was employed to regulate its conformation and further improve its advantages in preparing oil-in-water emulsion. RESULTS: The results indicated that acidification induced conversion of PPSI aggregates into linear chains. Increasing concentration promoted formation of cross-linked network structure shown in transmission electron microscopy images. Consequently, the viscosity, yield stress, storage modulus and flow activation energy significantly increased, further fabricating gel structure. Moreover, aggregation behavior suggested that more exposed proteins were involved in gel structure, thereby forming many hydrophobic cores as verified by fluorescence spectroscopy of pyrene. Afterwards, emulsion characteristics indicated that APPSI produced strong and thick steric hindrance around oil droplets and the coil-like interweaved chains locked the continuous phase, bringing strong elasticity and resistance to stress and creaming. Meanwhile, the lower fatty acid in APPSI-emulsion was released after simulated gastrointestinal digestion, mainly as a result of the high retention ratio of emulsion droplets. Furthermore, the elastic and viscous Lissajous curves suggested that the structure strength of APPSI-emulsion was similar to that of the salad dressing within the strain 53.22%. CONCLUSION: The conformation of PPSI after acidification at pH 3.0 was suitable for preparing the stable emulsion. The obtained emulsion could resist digestion and maintain a strong structure, comprising a cholesterol-free and low-fat salad dressing substitute. © 2023 Society of Chemical Industry.


Assuntos
Arachis , Polissacarídeos , Humanos , Emulsões/química , Água/química
2.
Crit Rev Food Sci Nutr ; : 1-24, 2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37665605

RESUMO

Pectin is widely spread in nature and it develops an extremely complex structure in terms of monosaccharide composition, glycosidic linkage types, and non-glycosidic substituents. As a non-digestible polysaccharide, pectin exhibits resistance to human digestive enzymes, however, it is easily utilized by gut microbiota in the large intestine. Currently, pectin has been exploited as a novel functional component with numerous physiological benefits, and it shows a promising prospect in promoting human health. In this review, we introduce the regulatory effects of pectin on intestinal inflammation and metabolic syndromes. Subsequently, the digestive behavior of pectin in the upper gastrointestinal tract is summarized, and then it will be focused on pectin's fermentation characteristics in the large intestine. The fermentation selectivity of pectin by gut bacteria and the effects of pectin structure on intestinal microecology were discussed to highlight the interaction between pectin and bacterial community. Meanwhile, we also offer information on how gut bacteria orchestrate enzymes to degrade pectin. All of these findings provide insights into pectin digestion and advance the application of pectin in human health.

3.
BMC Pregnancy Childbirth ; 23(1): 114, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36788485

RESUMO

BACKGROUND: The use of cervical strain elastography for nulliparous women during late-term pregnancy remains unclear. This study assesses the predictive value of late-term cervical strain elastography for successful induction of labor (IOL) in nulliparous women. METHODS: This single-centered, prospective study included 86 patients undergoing IOL between January 2020 and March 2022. Univariate and multivariate analyses were conducted to identify predictive factors for successful IOL. The predictive values were assessed using the area under receiver operating characteristic (ROC) curves. RESULTS: IOL was successful in 58 patients. The hardness ratio and cervical length were significantly associated with successful late-term IOL in nulliparous women. The predictive value of the combination of hardness ratio and cervical length was higher than that of cervical length alone. CONCLUSIONS: The hardness ratio and cervical length assessed by cervical strain elastography during late-term pregnancy are predictors of the success of IOL in nulliparous women. The predictive value of the combination of hardness ratio and cervical length was higher than that of cervical length alone.


Assuntos
Técnicas de Imagem por Elasticidade , Gravidez , Humanos , Feminino , Estudos Prospectivos , Valor Preditivo dos Testes , Trabalho de Parto Induzido , Paridade , Curva ROC , Colo do Útero/diagnóstico por imagem
4.
J Sci Food Agric ; 103(14): 7006-7020, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37319237

RESUMO

BACKGROUND: Recovery of high-purity tea saponin (TS), a promising non-ionic surfactant with well-documented properties, is one of the major challenges to broadening its industrial applications. In this study, an innovative and sustainable strategy for the highly-efficient purification of TS was developed by using well-designed highly-porous polymeric adsorbents. RESULTS: The prepared Pp-A with controllable macropores (~96 nm) and appropriate surface hydrophobic properties was found more favorable for achieving high adsorption efficiency towards TS/TS-micelles. Kinetic results showed the adsorption follows the pseudo-second-order model (R2 = 0.9800), and the Langmuir model is more qualified to explicate the adsorption isotherms with Qe-TS ~ 675 mg g-1 . Thermodynamic studies revealed the monolayer adsorption of TS was an endothermic process that was conducted spontaneously. Interestingly, ethanol-driven desorption (90% v/v ethanol) of TS was rapidly (< 30 min) complete due to the possible ethanol-mediated disassembling of TS-micelles. A possible mechanism that involves the interactions between the adsorbents and TS/TS-micelles, the formation and disassembling of TS-micelles was proposed to account for the highly efficient purification of TS. Afterwards, Pp-A-based adsorption method was developed to purify TS directly from industrial camellia oil production. Through selective adsorption, pre-washing, and ethanol-driven desorption, the applied Pp-A enabled the direct isolation of high-purity TS (~96%) with a recovery ratio > 90%. Notably, Pp-A exhibited excellent operational stability and is of high potential for long-term industrial application. CONCLUSION: Results ensured the practical feasibility of the prepared porous adsorbents in purifying TS, and the proposed methodology is a promising industrial-scale purification strategy. © 2023 Society of Chemical Industry.


Assuntos
Camellia , Saponinas , Poluentes Químicos da Água , Purificação da Água , Camellia/química , Porosidade , Micelas , Polímeros , Adsorção , Chá/química , Etanol , Cinética , Poluentes Químicos da Água/química , Purificação da Água/métodos
5.
Nat Mater ; 20(6): 841-850, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33479526

RESUMO

Metal fluorides, promising lithium-ion battery cathode materials, have been classified as conversion materials due to the reconstructive phase transitions widely presumed to occur upon lithiation. We challenge this view by studying FeF3 using X-ray total scattering and electron diffraction techniques that measure structure over multiple length scales coupled with density functional theory calculations, and by revisiting prior experimental studies of FeF2 and CuF2. Metal fluoride lithiation is instead dominated by diffusion-controlled displacement mechanisms, and a clear topological relationship between the metal fluoride F- sublattices and that of LiF is established. Initial lithiation of FeF3 forms FeF2 on the particle's surface, along with a cation-ordered and stacking-disordered phase, A-LixFeyF3, which is structurally related to α-/ß-LiMn2+Fe3+F6 and which topotactically transforms to B- and then C-LixFeyF3, before forming LiF and Fe. Lithiation of FeF2 and CuF2 results in a buffer phase between FeF2/CuF2 and LiF. The resulting principles will aid future developments of a wider range of isomorphic metal fluorides.

6.
Depress Anxiety ; 39(12): 881-890, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36321433

RESUMO

INTRODUCTION: Compared to research on adults with depression, relatively little work has examined white matter microstructure differences in depression arising earlier in life. Here we tested hypotheses about disruptions to white matter structure in adolescents with current and past depression, with an a priori focus on the cingulum bundles, uncinate fasciculi, corpus collosum, and superior longitudinal fasciculus. METHODS: One hundred thirty-one children from the Preschool Depression Study were assessed using a Human Connectome Project style diffusion imaging sequence which was processed with HCP pipelines and TRACULA to generate estimates of fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD) and radial diffusivity (RD). RESULTS: We found that reduced FA, reduced AD, and increased RD in the dorsal cingulum bundle were associated with a lifetime diagnosis of major depression and greater cumulative and current depression severity. Reduced FA, reduced AD, and increased RD in the ventral cingulum were associated with greater cumulative depression severity. CONCLUSION: These findings support the emergence of white matter differences detected in adolescence associated with earlier life and concurrent depression. They also highlight the importance of connections of the cingulate to other brain regions in association with depression, potentially relevant to understanding emotion dysregulation and functional connectivity differences in depression.


Assuntos
Substância Branca , Adulto , Criança , Adolescente , Humanos , Pré-Escolar , Substância Branca/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Depressão/diagnóstico por imagem , Rede Nervosa , Encéfalo , Anisotropia
7.
Appl Microbiol Biotechnol ; 106(5-6): 1919-1932, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35179629

RESUMO

Partially hydrolyzed konjac powder (PHKP) can be used to increase the daily intake of dietary fibers of consumers. To produce PHKP by enzymatic hydrolysis, a novel ß-mannanase gene (McMan5B) from Malbranchea cinnamomea was expressed in Pichia pastoris. It showed a low identity of less than 52% with other GH family 5 ß-mannanases. Through high cell density fermentation, the highest ß-mannanase activity of 42200 U mL-1 was obtained. McMan5B showed the maximal activity at pH 7.5 and 75 °C, respectively. It exhibited excellent pH stability and thermostability. Due to the different residues (Phe214, Pro253, and His328) in catalytic groove and the change of ß2-α2 loop, McMan5B showed unique hydrolysis property as compared to other ß-mannanases. The enzyme was employed to hydrolyze konjac powder for controllable production of PHKP with a weight-average molecular weight of 22000 Da (average degree of polymerization 136). Furthermore, the influence of PHKP (1.0%-4.0%) on the qualities of steamed bread was evaluated. The steamed bread adding 3.0% PHKP had the maximum specific volume and the minimum hardness, which showed 11.0% increment and 25.4% decrement as compared to the control, respectively. Thus, a suitable ß-mannanase for PHKP controllable production and a fiber supplement for steamed bread preparation were provided in this study. KEY POINTS: • A novel ß-mannanase gene (McMan5B) was cloned from Malbranchea cinnamomea and expressed in Pichia pastoris at high level. • McMan5B hydrolyzed konjac powder to yield partially hydrolyzed konjac powder (PHKP) instead of manno-oligosaccharides. • PHKP showed more positive effect on the quality of steamed bread than many other dietary fibers including konjac powder.


Assuntos
Amorphophallus , beta-Manosidase , Amorphophallus/genética , Clonagem Molecular , Concentração de Íons de Hidrogênio , Mananas/química , Onygenales , Pichia/genética , Pós , beta-Manosidase/química , beta-Manosidase/genética
8.
Angew Chem Int Ed Engl ; 61(28): e202203792, 2022 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-35460148

RESUMO

Photocaged, activity-based ubiquitin (Ub) probes (Ub-ABPs) have been developed for the time-resolved probing of deubiquitinating enzyme (DUB) activities, but many Ub-ABPs are still challenging to photocage because their warheads (e.g. propargylamide (PA) or dehydroalanine (Dha)) are difficult to temporally block and activate. Here, we describe a new C-terminal backbone modification strategy for the construction of photocaged Ub-ABPs in which a light-sensitive group is placed at the backbone amide bond of the Ub Gly75. This strategy enabled the facile generation of cell-permeable photocaged Ub-PA and Dha probes that could be activated to capture DUBs after photo-irradiation, and were used to profile DUBs in cells under specially designed conditions (e.g. in cells experiencing oxidative stress) or DUBs with isopeptide linkage selectivity. This backbone modification strategy is anticipated to provide a general solution for the development of photocaged Ub ABPs bearing any warheads for DUB profiling.


Assuntos
Ubiquitina , Ubiquitina/química , Ubiquitinação
9.
Chemistry ; 27(52): 13211-13220, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34319601

RESUMO

Direct conversion of methane (CH4 ) to fuels and other high value-added chemicals is an attractive technology in the chemical industry; however, practical challenges to sustainable processes remain. Herein, we report the preparation of a heterostructured Co-doped MgO-based catalyst through topological transformation of a MgCo-layered double hydroxide (LDH) calcination from 200 to 1100 °C. Remarkably, the catalyst can activate CH4 coupling to produce C2 H6 with a selectivity of 41.60 % within 3 h under full-spectrum irradiation through calcination of LDH at 800 °C. Characterization studies and catalytic results suggest that the highly dispersed active sites and large interfaces amongst the Co-doped MgO-based catalysts enable surface activation of CH4 to methyl (CH3 *), in turn promoting coupling of CH3 * to C2 H6 . This study introduces a promising pathway for photodriven CH4 coupling to give high value-added chemicals by using layered double hydroxides as a precursor.

10.
Chembiochem ; 21(23): 3313-3318, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32621561

RESUMO

Ubiquitin chains with distinct topologies play essential roles in eukaryotic cells. Recently, it was discovered that multiple ubiquitin units can be ligated to more than one lysine residue in the same ubiquitin to form diverse branched ubiquitin chains. Although there is increasing evidence implicating these branched chains in a plethora of biological functions, few mechanistic details have been elucidated. This concept article introduces the function, detection and chemical synthesis of branched ubiquitin chains; and offers some future perspective for this exciting new field.


Assuntos
Ubiquitina , Humanos , Ubiquitina/análise , Ubiquitina/síntese química , Ubiquitina/química , Ubiquitina/metabolismo
11.
Pediatr Res ; 87(5): 946-951, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31785592

RESUMO

BACKGROUND: Retinol-binding protein 4 (RBP-4) is an adipokine involved in regulating insulin sensitivity which would affect fetal growth. It is unclear whether RBP-4 is associated with fetal overgrowth, and unexplored which fetal growth factor(s) may mediate the association. METHODS: In the Shanghai Birth Cohort, we studied 125 pairs of larger-for-gestational-age (LGA, birth weight >90th percentile, an indicator of fetal overgrowth) and optimal-for-gestational-age (OGA, 25-75th percentiles) control infants matched by sex and gestational age. We measured cord blood concentrations of RBP-4, insulin, proinsulin, insulin-like growth factor-I (IGF-I), and IGF-II. RESULTS: Cord blood RBP-4 concentrations were elevated in LGA vs. OGA infants (21.9 ± 6.2 vs. 20.2 ± 5.1 µg/ml, P = 0.011), and positively correlated with birth weight z score (r = 0.19, P = 0.003), cord blood proinsulin (r = 0.21, P < 0.001), IGF-I (r = 0.24, P < 0.001), and IGF-II (r = 0.15, P = 0.016). Adjusting for maternal and neonatal characteristics, each SD increment in cord blood RBP-4 was associated with a 0.28 (0.12-0.45) increase in birth weight z score (P < 0.001). Mediation analyses showed that IGF-I could account for 31.7% of the variation in birth weight z score in association with RBP-4 (P = 0.01), while IGF-II was not an effect mediator. CONCLUSIONS: RBP-4 was positively associated with fetal overgrowth. IGF-I (but not IGF-II) may mediate this association.


Assuntos
Macrossomia Fetal/metabolismo , Fator de Crescimento Insulin-Like II/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Proteínas Plasmáticas de Ligação ao Retinol/metabolismo , Peso ao Nascer , Estudos de Casos e Controles , China , Diabetes Gestacional , Feminino , Sangue Fetal/metabolismo , Idade Gestacional , Humanos , Recém-Nascido , Insulina/sangue , Masculino , Gravidez
12.
Environ Res ; 189: 109900, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32980000

RESUMO

BACKGROUND: Although the effects of seasonal variations and ambient temperature on the incidence of tuberculosis (TB) have been well documented, it is still unknown whether ambient temperature change is an independent risk factor for TB. The aim of this study was to assess the association between ambient temperature change and the risk of TB admissions. METHOD: A distributed lag non-linear model (DLNM) combined with Poisson generalized linear regression model was performed to assess the association between ambient temperature change and the risk of TB admissions from 2014 to 2018 in Hefei, China. Two temperature change metrics including temperature change between neighboring days (TCN) and diurnal temperature range (DTR) were used to assess the effects of temperature change exposure. Subgroup analyses were performed by gender, age and season. Besides, the attributable risk was calculated to evaluated the public health significance. RESULTS: The overall exposure-response curves suggested that there were statistically significant associations between two temperature change metrics and the risk of TB admissions. The maximum lag-specific relative risk (RR) of TB admissions was 1.088 (95%CI: 1.012-1.171, lag 4 day) for exposing to large temperature drop (TCN= -4 °C) in winter. Besides, the overall cumulative risk of TB admissions increased continuously and peaked at a lag of 7 days (RR=1.350, 95%CI: 1.120-1.628). Subgroup analysis suggested that exposure to large temperature drop had an adverse effect on TB admissions among males, females and adults. Similarly, large level of DTR exposure (DTR=15 °C) in spring also increased the risk of TB admissions on lag 0 day (RR=1.039, 95%CI: 1.016-1.063), and the cumulative RRs peaked at a lag of 1 days (RR=1.029, 95%CI: 1.012-1.047). We also found that females and elderly people were more vulnerable to the large level of DTR exposure. Additionally, the assessment of attributable risk suggested that taking target measures for the upcoming large temperature drop (b-AF = 4.17%, 95% eCI: 1.24%, 7.22%, b-AN = 1195) may achieve great public health benefits for TB prevention. CONCLUSION: This study suggests that ambient temperature change is associated with the risk of TB admissions. Besides, TCN may be a better predictor for the TB prevention and public health.


Assuntos
Benchmarking , Tuberculose , Idoso , China , Feminino , Hospitalização , Humanos , Masculino , Temperatura , Tuberculose/epidemiologia
13.
Environ Res ; 184: 109343, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32192989

RESUMO

BACKGROUND: The current evidence has presented mixed results between air pollutants exposure and the progression of tuberculosis (TB). The purpose of this study was to explore the association between short-term exposure to air pollutants and the risk of TB outpatient visits in Hefei, China. METHODS: Time-series analysis was used to assess the effect of short-term exposure to ambient air pollutants on the risk of TB outpatient visits. A Poisson generalized linear regression model combined with a distributed lag non-linear model (DLNM) was applied to explore the association. The effects of different gender (male, female), age (≤65 years old, >65 years old) and season (cold season, warm season) on the risk of TB were investigated by stratified analysis. Sensitivity analyses were conducted to test the robustness of our findings. RESULTS: A total of 22,749 active TB cases were identified from November 1, 2013 to December 31, 2018 in Hefei. The overall exposure-response curve showed that the concentration of particulate matter with aerodynamic diameter less than 2.5 µm (PM2.5) and nitrogen dioxide (NO2) exposure were positively correlated with the risk of TB outpatient visits, while ozone (O3) and sulfur dioxide (SO2) exposure were negatively correlated with the risk of TB outpatient visits. The maximum lag-specific and cumulative relative risk (RR) of TB outpatient visits were 1.057 [95%CI: 1.002-1.115, lag 3 day] and 1.559 (95%CI: 1.057-2.300, lag 13 days) for each 10 µg/m³ increase in PM2.5; 1.026 (95% CI: 1.008-1.044, lag 0 day) and 1.559 (95%CI: 1.057-2.300, lag 07 days) for each 10 µg/m³ increase in NO2; 0.866 (95% CI: 0.801-0.935, lag 5 day) and 0.852 (95%CI: 1.01-1.11, lag 0-14 days) for each 10 µg/m³ increase in SO2 in the single-pollutant model. There was only a negative association between O3 exposure and the cumulative risk of TB outpatient visits (RR = 0.960, 95%CI: 0.936-0.984, lag 07 days). Stratified analyses showed that the effects of SO2 and O3 exposure were different between warm and cold seasons. The effect of NO2 exposure remained statistically significant in male, younger, and cold season subgroups. Besides, elderly people are more susceptible to PM2.5 exposure. CONCLUSION: This study suggests that exposure to PM2.5, NO2, SO2, and O3 are associated with the risk of TB outpatient visits. Seasonal variation may have a greater impact on the risk of TB outpatient visits compared with gender and age.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Tuberculose , Idoso , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , China/epidemiologia , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Feminino , Humanos , Masculino , Pacientes Ambulatoriais , Material Particulado/análise , Material Particulado/toxicidade , Tuberculose/induzido quimicamente , Tuberculose/epidemiologia
14.
Environ Res ; 180: 108843, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31670082

RESUMO

BACKGROUND: Previous studies have shown that ambient air pollution exposure can increase the risk of type 2 diabetes mellitus (T2DM) significantly. In consideration of the common underlying pathophysiologic mechanisms, exposure to air pollution may also increase the risk of gestational diabetes mellitus (GDM), but the current evidence was inconsistent and has not well been systematically reviewed. Our goal was to perform a systematic review and meta-analysis assessing the association between air pollution exposure and GDM. METHODS: An extensive literature search was conducted in selected electronic databases for related human epidemiological studies published in English language. Summary effect estimates were calculated using random-effect models for a) risk per unit increase in continuous air pollutant concentration and b) risk of high versus low exposure level in individual study if each exposure that had been examined in ≥2 studies. We evaluated the heterogeneity using Cochran's Q test and quantified it by I2 statistic. Publication bias was also evaluated through the funnel plot when sufficient number of studies are available. RESULTS: A total of 11 studies evaluating the association between GDM and exposure to air pollution were identified finally. The summary odds ratio (OR) for incidence of GDM following a 10 µg/m3 increase in PM2.5 exposure during the second trimester was 1.04 (95% Confidence Interval (CI): 1.01, 1.09) and in NOx during the first trimester was 1.03 (95%CI: 1.00, 1.07) per 10 ppb increase, while for high versus low SO2 exposure during the second trimester was 1.25 (95%CI: 1.02, 1.53). High heterogeneity among study-specific results in majority of the analyses were observed, and attributed to different exposure assessment methods, populations, study locations, and covariates adjustment. Publication bias cannot be excluded because of the inclusion of small number of studies. CONCLUSIONS: The present study supports the evidence that air pollution exposure increases the risk the GDM, albeit the existence of high heterogeneity. Further studies are necessary to elaborate the suggestive associations. These results are of public health significance since worsening air pollution in developing countries has been expected to increase the risk of GDM development.


Assuntos
Poluição do Ar/estatística & dados numéricos , Diabetes Mellitus Tipo 2 , Diabetes Gestacional/epidemiologia , Exposição Ambiental/estatística & dados numéricos , Poluentes Atmosféricos , Feminino , Humanos , Material Particulado , Gravidez
15.
J Chem Phys ; 152(10): 104703, 2020 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-32171206

RESUMO

Organic-inorganic perovskites are one of the most promising photovoltaic materials for the design of next generation solar cells. The lead-based perovskite prepared with methylammonium and iodide was the first in demonstrating high power conversion efficiency, and it remains one of the most used materials today. However, perovskites prepared by mixing several halides and several cations systematically yield higher efficiencies than "pure" methylammonium lead iodide (MAPbI3) devices. In this work, we unravel the excited-state properties of a mixed-halide (iodide and bromide) and mixed-cation (methylammonium and formamidinium) perovskite. Combining time-resolved photoluminescence, transient absorption, and optical-pump-terahertz-probe experiments with density functional theory calculations, we show that the population of higher-lying excited states in the mixed material increases the lifetime of photogenerated charge carriers upon well above-bandgap excitation. We suggest that alloying different halides and different cations reduces the structural symmetry of the perovskite, which partly releases the selection rules to populate the higher-energy states upon light absorption. Our investigation thus shows that mixed halide perovskites should be considered as an electronically different material than MAPbI3, paving the way toward further materials optimization and improved power conversion efficiency of perovskite solar cells.

16.
Chemistry ; 25(72): 16668-16675, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31625216

RESUMO

The development of powerful and general methods to acquire ubiquitin (Ub) chains has prompted the deciphering of Ub-mediated processes. Herein, the cysteine-aminoethylation assisted chemical ubiquitination (CAACU) strategy is extended and improved to enable the efficient semi-synthesis of atypical Ub chain analogues and Ub-based probes. Combining the Cys aminoethylation and the auxiliary-mediated protein ligation, several linkage- and length-defined atypical Ub chains including di-Ubs, K27C-linked tri-Ub, K11/K48C-branched tri-Ub, and even the SUMOlated Ub are successfully prepared from recombinantly expressed starting materials at about a 9-20 mg L-1 expression level. In addition, the utility of this strategy is demonstrated with the synthesis of a novel non-hydrolyzable di-Ub PA probe, which may provide a new useful tool for the mechanistic studies of deubiquitinase (DUB) recognition.

17.
Am J Public Health ; 109(11): 1597-1604, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31536409

RESUMO

Objectives. To describe the incidence, risk factors, and potential causes of preterm birth (PTB) in China between 2015 and 2016.Methods. The China Labor and Delivery Survey was a population-based multicenter study conducted from 2015 to 2016. We assigned each birth a weight based on the sampling frame. We calculated the incidence of PTB and the multivariable logistic regression, and we used 2-step cluster analysis to examine the relationships between PTB and maternal, fetal, and placental conditions.Results. The weighted nationwide incidence of PTB was 7.3% of all births and 6.7% of live births at 24 or more weeks of gestation. Of the PTBs, 70.5% were born after 34 weeks and 42.7% were iatrogenic. Nearly two thirds of all preterm births were attributable to maternal, fetal, or placental conditions, and one third had unknown etiology.Conclusions. This study provided information on the incidence of PTB in China and identified several factors associated with PTB. The high frequency of iatrogenic PTB calls for a careful assessment and prudent management of such pregnancies, as PTB has short- and long-term health consequences.


Assuntos
Nascimento Prematuro/epidemiologia , Adulto , China/epidemiologia , Estudos Transversais , Feminino , Idade Gestacional , Humanos , Idade Materna , Saúde Materna , Gravidez , Características de Residência , Fatores de Risco , Adulto Jovem
18.
Environ Res ; 168: 448-459, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30391837

RESUMO

Air pollution has been evaluated as a possible risk factor for Parkinson's disease (PD), but, the present results are inconsistent and have not been combined. We performed a systematic review and meta-analysis to estimate the association between long-term exposure to ambient air pollution and PD, given the nature of disease etiology. A total of 10 studies were identified by searching Web of Science, Science Direct, and PubMed before October 2017. We found a significantly increased risk of PD with 10 parts per billion (ppb) increase in nitrogen oxides (NOx) exposure (relative risk (RR) = 1.06; 95% confidence interval (CI): 1.04, 1.09). The pooled RR for the association between carbon monoxide (CO) exposure, 1 parts per million (ppm) increment, and the risk of PD was 1.65 (95% CI: 1.10, 2.48). The pooled RRs for the association between nitrogen dioxide (NO2) and ozone (O3) exposure per 1 ppb increment, and the risk of PD were 1.01 (95% CI: 1.00, 1.03) and 1.01 (95% CI: 1.00, 1.02), respectively. There was a significant heterogeneity in the meta-analysis for fine particulate matter (PM2.5), NO2, sulfur dioxide (SO2), and CO. We concluded that NO2, NOx, CO and O3 exposure were associated with an increased risk of PD, although there is high risk of bias. The dose-response effects evaluated by high-quality studies are needed. Researches should be expanded to low- and/or middle- income countries where indoor and outdoor air pollution are high. CAPSULE: Long-term exposure to ambient NO2, NOx, CO and O3 can increase the risk of Parkinson's disease.


Assuntos
Poluição do Ar/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Doença de Parkinson/epidemiologia , Poluentes Atmosféricos , Humanos , Material Particulado
19.
Andrologia ; 51(7): e13304, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31090230

RESUMO

Over the past decades, there is an increasing number of association studies of telomere length (TL) and the risk and recurrence of prostate cancer (PCa), but the results are inconsistent. Hence, we identify the relevant studies published in English on or before 10 January 2019 conducting a literature review in the electronic databases including PubMed, EMBASE and Cochrane Library. Twelve studies (with 19 data sets) were included in this meta-analysis, five of which were associated with risk assessment, six of which reported recurrence of PCa and one of which included them. Our meta-analysis demonstrated a positive association of shorter telomeres in patients with PCa, but without statistical significance (OR, 1.23; 95% CI: 0.91-1.66). Shorter telomeres in stroma (OR, 2.40; 95% CI: 1.61-3.56) and epithelium (OR, 1.70; 95% CI: 1.33-2.16) were positively correlated with PCa, but in leucocyte (OR, 0.81; 95% CI: 0.73-0.91) had negative association with PCa. Furthermore, two studies combined yielded a pooled OR of 2.87 (95% CI: 1.22-6.76) for the association between shorter TL and metastasis. These results are novel and give further strength to formulate eligible individualising treatment and surveillance strategies.


Assuntos
Recidiva Local de Neoplasia/genética , Neoplasias da Próstata/genética , Encurtamento do Telômero , Telômero/genética , Conjuntos de Dados como Assunto , Humanos , Masculino , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/patologia , Próstata/patologia , Neoplasias da Próstata/patologia , Medição de Risco
20.
Small ; 14(46): e1802295, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30176111

RESUMO

Malaria is caused by Plasmodium sp. parasites transmitted by infected female Anopheles sp. mosquitoes. The survival of the parasites in the host relies on detoxifying free heme by biocrystallization into insoluble crystals called hemozoin. This mechanism of self-preservation is targeted by a certain class of antimalarial drugs, which are screened and selected based on their capacity to inhibit the formation of hemozoin crystals. Therefore, experimental techniques capable of accurately characterizing the kinetics of crystal formation are valuable. Relying on the optical anisotropy of hemozoin, the kinetics of ß-hematin crystal formation through the statistical analysis of photon counts of dynamic depolarized light scattering (DDLS), in the absence and presence of an antimalarial drug (chloroquine, CQ), is described. It is found that CQ has an impact on both the nucleation and growth of the crystals.

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