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1.
J Nanosci Nanotechnol ; 20(2): 1074-1082, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383107

RESUMO

The microcapsule particles were successfully prepared by means of in-situ copolymerization of layered double hydroxides (LDHs) with the melamine resin monomers, improving the compatibility of inorganic flame retardant LDH with polymer. The electron beam irradiation was introduced into the process to enhance the mechanical properties and thermostability of the flame retardant composite material. The flame-retardant composites were prepared by incorporating the microcapsule LDH into ethylene vinyl acetate (EVA). The compatibility of microcapsule particles with EVA, combustion and thermal behaviors were detected in sequence through SEM, TG analyses, LOI, UL-94 level and mechanical tests. It was shown that the irradiated EVA/LDH@MF composite had showed the best performances of flame retardancy and mechanical properties due to microencapsulation and irradiation processes. The uniform dispersion of microencapsulated LDH in the EVA matrix was due to the good compatibility of MF shell with EVA keeping the mechanical properties of EVA matrix. The irradiated EVA/LDH@MF with 200 kGy dose achieved a limiting oxygen index (LOI) of 25.5% and a UL-94 V-1 rating. When the dose rate was 100 kGy, the EVA/LDH@MF composite had the best mechanical properties of EVA composites. The microencapsulation of LDH with MF shell incorporated into EVA three-dimensioned network through electron beam irradiation induced crosslinking to enhance mechanical properties.

2.
J Nanosci Nanotechnol ; 20(3): 1578-1588, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492320

RESUMO

Polyacrylonitrile (PAN) precursors have been polymerized at different radical polymerization temperatures for preparing sulfurized-polyacrylonitrile (S-PAN) composite cathodes in rechargeable lithium sulfur battery. The physical properties of these composites have been investigated using X-ray diffraction, Fourier transform infrared spectrometry, Raman spectroscopy, Brunner-Emmet-Teller measurement and Gel permeation chromatography analysis. The electrochemical performance of the S-PAN composite cathodes made from the PAN precursor was investigated. The results showed that the molecular weight distribution of the PAN precursors affected the electrochemical performance of the S-PAN made from the PAN precursor. S-PAN composites derived from PAN with a narrower molecular weight distribution at 65 °C were exhibit the best electrochemical performance in lithium-sulfur battery.

3.
J Nanosci Nanotechnol ; 20(3): 1822-1831, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492348

RESUMO

Thermal behavior of hydrotalcites, which is a calcination process, is critical to prepare the metal oxide catalysts with high performances in the practical applications. In this paper, the MgFe-LDH with Mg/Fe molar ratio of 3.0 was prepared by urea method and the calcined products are obtained by calcining at different temperatures (473 K, 573 K, 673 K, 773 K, 873 K and 973 K) under a N2 atmosphere for 4 h. The structure, morphology, texture, pyrolysis kinetics and mechanism of the MgFe-LDH were studied in detail. On one hand, based on the TG/DSC curves, Starink, Kissinger and Flynn-Wall-Ozawa (FWO) methods were used to calculate the activation energy, on the other hand, the Satava-Sesták, Achar and Málek methods were used to define the most probable reaction mechanisms of pyrolysis behavior. The results suggested that the thermal decomposition of the LDH experienced two steps, i.e., removal of the interlayer water, followed by dehydroxylation and decarbonation. Moreover the Mákel method was used to define the most probable reaction mechanisms of the pyrolysis behavior.

4.
Nat Chem Biol ; 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31591566

RESUMO

Iron is essential for a broad range of biochemical processes in the brain, but the mechanisms of iron metabolism in the brain remain elusive. Here we show that iron functionally translocates among brain regions along specific axonal projections. We identified two pathways for iron transport in the brain: a pathway from ventral hippocampus (vHip) to medial prefrontal cortex (mPFC) to substantia nigra; and a pathway from thalamus (Tha) to amygdala (AMG) to mPFC. While vHip-mPFC transport modulates anxiety-related behaviors, impairment of Tha-AMG-mPFC transport did not. Moreover, vHip-mPFC iron transport is necessary for the behavioral effects of diazepam, a well-known anxiolytic drug. By contrast, genetic or pharmacological promotion of vHip-mPFC transport produced anxiolytic-like effects and restored anxiety-like behaviors induced by repeated restraint stress. Taken together, these findings provide key insights into iron metabolism in the brain and identify the mechanisms underlying iron transport in the brain as a potential target for development of novel anxiety treatments.

5.
J Med Genet ; 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31501240

RESUMO

BACKGROUND: Male infertility is a prevalent issue worldwide, mostly due to the impaired sperm motility. Multiple morphological abnormalities of the sperm flagella (MMAF) present aberrant spermatozoa with absent, short, coiled, bent and irregular-calibre flagella resulting in severely decreased motility. Previous studies reported several MMAF-associated genes accounting for approximately half of MMAF cases. METHODS AND RESULT: We conducted genetic analysis using whole-exome sequencing in 88 Han Chinese MMAF probands. CFAP65 homozygous mutations were identified in four unrelated consanguineous families, and CFAP65 compound heterozygous mutations were found in two unrelated cases with MMAF. All these CFAP65 mutations were null, including four frameshift mutations (c.1775delC [p.Pro592Leufs*8], c.3072_3079dup [p.Arg1027Profs*41], c.1946delC [p.Pro649Argfs*5] and c.1580delT [p.Leu527Argfs*31]) and three stop-gain mutations (c.4855C>T [p.Arg1619*], c.5270T>A [p.Leu1757*] and c.5341G>T [p.Glu1781*]). Additionally, two homozygous CFAP65 variants likely affecting splicing were identified in two MMAF-affected men of Tunisian and Iranian ancestries, respectively. These biallelic variants of CFAP65 were verified by Sanger sequencing and were absent or very rare in large data sets aggregating sequence information from various human populations. CFAP65, encoding the cilia and flagella associated protein 65, is highly and preferentially expressed in the testis. Here we also generated a frameshift mutation in mouse orthologue Cfap65 using CRISPR-Cas9 technology. Remarkably, the phenotypes of Cfap65-mutated male mice were consistent with human MMAF. CONCLUSIONS: Our experimental observations performed on both human subjects and on Cfap65-mutated mice demonstrate that the presence of biallelic mutations in CFAP65 causes the MMAF phenotype and impairs sperm motility.

6.
Nat Cell Biol ; 21(9): 1152-1163, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31481791

RESUMO

Ca2+/calmodulin-dependent kinase II (CaMKII) is a multifunctional serine/threonine kinase family, and its δ isoform is predominant in the heart. Excessive CaMKII activation plays a pivotal role in the pathogenesis of severe heart conditions, including myocardial infarction, cardiomyopathy and heart failure. However, the identity of CaMKII splice variants and the mechanism(s) underlying CaMKII-mediated cardiac pathology remain elusive. Here, we show that CaMKII-δ9, the most abundant CaMKII-δ splice variant in human heart, potently promotes cardiomyocyte death, cardiomyopathy and heart failure by disrupting cardiomyocyte genome stability. Mechanistically, CaMKII-δ9, but not the previously well-studied CaMKII-δ2 and CaMKII-δ3, targets the ubiquitin-conjugating enzyme E2T (UBE2T) for phosphorylation and degradation, disrupting UBE2T-dependent DNA repair and leading to the accumulation of DNA damage and genome instability. These findings not only reveal a crucial role of CaMKII in the regulation of DNA repair, but also mark the CaMKII-δ9-UBE2T-DNA damage pathway as an important therapeutic target for cardiomyopathy and heart failure.

7.
Math Biosci Eng ; 16(5): 4645-4659, 2019 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-31499682

RESUMO

OBJECTIVE: The aim of this article is to compare the oncological outcomes of laparoscopic and open resection for colon cancer. METHOD: Search the publications on comparison the efficacy of laparoscopic surgery comparison with open surgery in treatment outcomes of colon cancer to May, 2018. After rigorous reviewing on quality, the data was extracted from eligible trials. All trials analyzed the summary hazard ratios (HRs) of the endpoints of interest, including intraoperative and postoperative outcomes. RESULTS: A total of 13 trials were met our inclusion criteria. With the pooled result of duration of surgery indicate that laparoscopic surgery was associated with a trend longer operate time (SMD = 0.58, 95% CI 0.17-0.99; P=0.005) , shorter length of hospital stay (SMD = -0.57, 95% CI -1.00--0.15; P = 0.008) and postoperative hospital stay (SMD = -0.66, 95% CI -0.99--0.33; P = 0.0001) , less blood loss (SMD = -0.68, 95% CI -1.12--0.24; P = 0.002), shorter incision length (SMD = -4.61, 95% CI -5.79--3.43; P<=0.00001 and less wound infection (OR = 0.30, 95% CI 0.13-0.67; P = 0.004). However, there were no differences in the number of lymph nodes harvested (P = 0.17), ileus (P = 0.91), pulmonary infection (P = 0.22) and postoperative complications (P = 0.24) between the 2 groups. CONCLUSION: Laparoscopic surgery had similar intraoperative and postoperative recovery parameters to those of the patients in the open group. The patients treated with laparoscopic had a trend longer operate time, shorter hospital stays, less intra-operative blood loss, faster recovery and lower incidence of wound infection. Whether it can be expected to be a standardization operation method for colon carcinoma still need more random clinical trials to be verified.

8.
Artigo em Inglês | MEDLINE | ID: mdl-31562207

RESUMO

BACKGROUND: To explore the relationship between family history of esophageal cancer, SNPs, and the risk of esophageal squamous cell carcinoma (ESCC), we performed a population-based case-control study and developed a Genetic Family-history-related Risk (GFR) and non-Family-history-related Risk (GnFR) score to quantify the cumulative genetic risk. METHODS: We genotyped 87 genetic variants and constructed GFR and GnFR scores for 1041 patients and 1,764 controls. RESULTS: ESCC risk increased with higher GFR score (P-value for trend = 0.0096). Among the subgroup with a positive family history, we observed a nearly seven-fold (95% confidence interval (CI): 1.92-24.77) higher risk of ESCC in the highest GFR score group. The corresponding estimate was only two-fold (95% CI: 1.41-3.93), in the stratum without a family history. Certain cell signaling pathways and immune-related pathways were enriched specifically in familiar ESCC. A reconstructed cohort analysis showed that cumulative risk of esophageal cancer at age 75 was 13.3%, 10.2%, 8.2% and 5.1%, respectively, in four subgroups as defined by first-degree relatives of cases or controls with high or low genetic risk score. The cohort of relative of ESCC cases with low genetic risk score exhibit a higher cumulative risk than the cohort of relative of controls with high genetic risk score, demonstrating the major role of environmental factors. CONCLUSIONS: Future studies are needed to understand the mechanisms of shared genetic susceptibility and environmental exposures contributing to ESCC. IMPACT: We highlight the need of preventive strategies to screen certain genetic polymorphisms, especially in individuals with a family history.

9.
Ann Hum Genet ; 2019 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-31495922

RESUMO

Intellectual disability (ID) describes a wide range of serious human diseases caused by defects in central nervous system development and function. Some mutant genes have been found to be associated with these diseases, but not all cases can be explained, thus suggesting that other disease-causing genes have not yet been discovered. Sialic acid is involved in a number of key biological processes, including embryo formation, nerve cell growth, and cancer cell metastasis, and very recently it has been suggested that N-acetylneuraminic acid synthase-mediated synthesis of sialic acid is required for brain and skeletal development. CMP-sialic acid synthetase (CMAS) is one of four enzymes involved in NeuNAc metabolism, as it catalyzes the formation of CMP-NeuNAc. Before the present study, no links between mutations in CMAS and incidences of human ID had been reported. In the current study, we recruited a recessive nonsyndromic ID pedigree with consanguineous marriage in which all patients have typical clinical manifestations of ID. We identified the NM_018686.3:c.563G > A (p.Arg188His) substitution in CMAS as being responsible for the disease in this family. Conservation analysis, structural prediction, and enzyme activity experiments demonstrated that (p.Arg188His) influences protein dimerization and alters CMAS enzyme activity. Our results offer a new orientation for future research and clinical diagnosis.

11.
J Hazard Mater ; 381: 121208, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31563672

RESUMO

Contaminated mining sites require ecological restoration work, of which phytoremediation using appropriate plant species is an attractive option. Our present study is focused on one typical contaminated mine site with indigenous plant cover. The X-ray absorption near edge structure (XANES) analysis indicated that Cu (the major contaminant) was primarily associated with goethite (adsorbed fraction), with a small amount of Cu oxalate-like species (organic fraction) in mine affected soil. With growth of plant species like Miscanthus floridulus and Stenoloma chusanum, the Cu-oxalate like organic species in rhizosphere soil significantly increased, with corresponding decrease in Cu-goethite. In the root cross-section of Miscanthus floridulus, synchrotron-based micro-X-ray fluorescence (µ-XRF) microscopy and micro-XANES results indicated that most Cu was sequestered around the root surface/epidermis, primarily forming Cu alginate-like species as a Cu-tolerance mechanism. From the root epidermis to the cortex and vascular bundle, more Cu(I)-glutathione was observed, suggesting reductive detoxification ability of Cu(II) to Cu(I) during the transport of Cu in the root. The observation of Cu-histidine in root internal cell layers showed another Cu detoxification pathway based on coordinating amino ligands. Miscanthus floridulus showed ability to accumulate phosphorous and nitrogen nutrients in rhizosphere and may be an option for in situ phytostabilization of metals in contaminated mining area.

12.
Diabetes Res Clin Pract ; 156: 107865, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31545979

RESUMO

AIMS: We investigated whether serum haptoglobin (Hp) levels play a role in the development and progression of diabetic kidney disease (DKD) in type 2 diabetes mellitus (T2DM) patients in a Chinese Han population, which has not been previously investigated. METHODS: We recruited 233 participants who had suffered from T2DM for more than 10 years, including 118 subjects with DKD (case) and 115 subjects without DKD (control). Serum Hp levels were measured by an enzyme-linked immunosorbent assay. RESULTS: Serum Hp levels were significantly higher (P = 0.0258) in case group (2.74 (1.77, 3.48) g/L) than control (2.29 (0.98, 3.48) g/L). The serum Hp level was significantly positively associated with both logarithmically transformed (log-transformed) serum creatinine (r = 0.1663, P = 0.011) and albuminuria levels (r = 0.1793, P = 0.0062) and was negatively associated with the log-transformed estimated glomerular filtration rate (r = -0.1482, P = 0.0237). Multiple linear regression analysis revealed that serum Hp levels were significantly correlated with serum creatinine levels (P = 0.0088) after adjusting for confounding risk factors. CONCLUSIONS: Our findings suggest that serum Hp levels may be used as a potential biomarker for the early diagnosis and monitoring of DKD in T2DM patients.

13.
Braz J Infect Dis ; 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31542378

RESUMO

OBJECTIVE: The clinical significance of coexistence of HBsAg/anti-HBs in chronic hepatitis B (CHB) patients remains controversial. This study was aimed to assess the association of this serological pattern with hepatocellular carcinoma (HCC) in patients with CHB. METHODS: In this cross-section study, 206 CHB patients with coexistence of HBsAg/anti-HBs and 206 CHB patients with HBsAg alone were included to evaluate the risk of HCC development by logistic regression analysis. In addition, a retrospective cohort of 260 patients with CHB was recruited to estimate the cumulative incidence of HCC by Kaplan-Meier analysis. RESULTS: The serological pattern of coexistence of HBsAg/anti-HBs, with high levels of ("High") HBsAg/low levels of ("Low") anti-HBs, were considered as independent risk factors for HCC. In particular, patients with "High" HBsAg/"High" anti-HBs [odds ratio (OR), 4.295; 95% confidence interval (CI), 1.104-16.699; p = 0.035] and "Low" HBsAg/ "High" anti-HBs (OR, 3.207; 95%CI, 1.299-7.919; p = 0.012) exhibited significantly higher risk for HCC development. However, only "Low" HBsAg /"High" anti-HBs might increase risk of HCC in CHB patients with high HBV load (logrank p < 0.001) in our cohort study. CONCLUSION: The coexistence of "Low" HBsAg /"High" anti-HBs might increase the risk of HCC development in CHB patients with high HBV load, which reflected that the long-term interaction between immune response and virus might lead to the development of HCC. The identification of the patients with poor prognosis will help clinicians to refine the therapeutic decisions and individualize follow-up strategies.

14.
Exp Dermatol ; 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31505074

RESUMO

Systemic sclerosis (SSc) is an autoimmune disease mainly characterized by persistent inflammation and fibrosis. The receptor tyrosine kinase (RTK) signal pathway plays an important role in the process of SSc, and Grb2 associated binding protein (GAB) is crucial in activating RTK signaling. A previous study found elevated levels of GAB1 in bleomycin (BLM)-induced fibrotic lungs, but the effects of GAB1 in SSc remain unclear. Our aim was to investigate whether GAB1 was dysregulated and its potential role in SSc. Compared with healthy donors, we found GAB1 expression was 1.6-fold higher in peripheral blood mononuclear cells (PBMC), 2.5-fold higher in CD4+ T cells, and 2-fold higher in skin from of SSc patients (P < 0.01). At the same time, the levels of type one collagen (COLI) were also significantly increased (1.8-fold higher) in SSc skin. Additionally, BLM-induced SSc mice showed mRNA levels of Gab1 2-fold higher than saline-treated controls, and Gab1 expression correlated positively with collagen content. A further in vitro study showed silencing of GAB1 suppressed inflammatory gene expression in TNF-α induced fibroblasts. Additionally, GAB1 deficiency prominently inhibited cell proliferation and reduced COLI protein levels in TGF-ß induced fibroblasts. Taken together, these data suggest that GAB1 has a relatively high expression rate in SSc, and knockdown of GAB1 may attenuate SSc by stimulating inflammatory and fibrotic processes.

15.
Reproduction ; 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31505459

RESUMO

Fertilization failure often occurs during in vitro fertilization (IVF) cycles despite apparently normal sperm and oocytes. Accumulating evidence suggests that mitochondria play crucial roles in the regulation of sperm function and male fertility. 3-Nitrophthalic acid (3-NPA) can induce oxidative stress in mitochondria, and melatonin, as an antioxidant, can improve mitochondrial function by reducing mitochondrial oxidative stress. The role of sperm mitochondrial dysfunction in fertilization failure during in vitro fertilization (IVF) is unclear. The present study revealed that spermatozoa with low, or poor, fertilization rates had swollen mitochondria, increased mitochondria-derived ROS, and attenuated mitochondrial respiratory capacity. 3-NPA treatment enhanced mitochondrial dysfunction in sperm. Spermatozoa with poor fertilization rates, and spermatozoa treated with 3-NPA, had reduced penetration ability. The concentration of melatonin was decreased in semen samples with low and poor fertilization rates. Melatonin, not only decreased excessive mitochondria-derived ROS, but also "rescued" the reduced penetration capacity of spermatozoa treated with 3-NPA. Taken together, the study suggested that mitochondria-derived ROS and mitochondrial respiratory capacity are independent bio-markers for sperm dysfunction, and melatonin may be useful in improving sperm quality and overall male fertility.

16.
Artigo em Inglês | MEDLINE | ID: mdl-31556594

RESUMO

Intervertebral disc degeneration associated back pain is the most common cause of disability worldwide; however, no safe and effective treatments have been available. Here, we report a new functionalized nanofullerene conjugated with a peptide that binds specifically to a formyl peptide receptor-1 (FPR-1) expressed on activated macrophages. The new nanoparticle (aka FT-C60) was synthesized by conjugating carboxyl-C60 with the primary amine group of the peptide with a fluorescence dye for easy detection. The new nanoparticle was characterized by X-ray photoelectron spectroscopy, mass spectroscopy, and gel electrophoresis. It possessed effective radical (hydroxyl and superoxide anions) scavenging capabilities in electron paramagnetic resonance spectroscopy. In cultured cells, the nanoparticle FT-C60 demonstrated preferential binding to FPR-1 on activated macrophages and significantly attenuated mRNA expressions of proinflammatory factors including interleukin-6, interleukin-1, tumor necrosis factor-alpha, and cyclooxygenase-2. In vivo animal studies exhibited that a single intravenous injection of FT-C60 effectively alleviated pain in an established mouse model of radiculopathy for up to post-operation day (POD) 12. Ex vivo near-infrared fluorescence imaging of the mouse spine confirmed the targeting property of FT-C60 toward the injured disc on POD 14. Quantitative analysis of histological staining on spine sections showed that nanoparticle FT-C60 dramatically reduced inflammation at the local injury site compared to injury only on POD 7. In summary, we developed a novel targeted nanoparticle for treatment of lumbar radiculopathy by systemic delivery. This is a first-of-its-kind study for developing a novel class of targeted and systemic nanoparticle therapeutics to treat degenerative disc diseases.

17.
J Dermatol Sci ; 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31522824

RESUMO

BACKGROUND: The progression of human skin aging has a strong genetic basis. However, recent studies have mainly focused on Caucasian populations and we have thus performed a genetic association study on skin aging signs in Han Chinese population. OBJECTIVE: To investigate genetic risk factors in skin aging in Han Chinese female, we performed a genome-wide association study. METHODS: We collected genotype data from 1534 Han Chinese female from Taizhou cohort and evaluated 15 skin aging phenotypes by using the validated skin aging SCINEXA™ score. Genetic associations were tested by linear and logistic regression analyses and adjusted for potential confounders. RESULTS: Six genomic regions significantly associated with a risk for skin aging were revealed : 6q24.2 (rs3804540, P = 4.6 × 10-9, additive model) with size of pigmented spots on forehead, 10q26.13 (rs4962295, P = 1.9  × 10-8, additive model) with wrinkles under eyes, 15q21.1 (rs28392847, P = 1.6 × 10-8, additive model) with crow's feet, 2p25.1 (rs191497052, P = 5.5 × 10-9, dominant model) with telangiectasia, 13q34 (rs3825460, P = 3.7 × 10-8, dominant model) with size of pigmented spots on cheeks and 16p13.11(rs76053540, P = 5.0 × 10-9, dominant model) with nasolabialfold. The signal on 15q21.1 was replicated in the meta-analysis with two independent Caucasian cohorts (P = 8.6 × 10-10). We have also successfully replicated in our cohort an association between SNP rs1048943 of gene CYP1A1 (P = 7.1 × 10-4) and pigmented spots on cheeks previously described in Caucasian cohort. CONCLUSIONS: Our study has identified new genetic risk factors for signs of skin aging in the Han Chinese. This study suggests there are differences in genetic susceptibility to skin aging between Caucasians and the Han Chinese.

18.
Hum Genet ; 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31535215

RESUMO

Premature ovarian insufficiency (POI) is a major cause of reduced female fertility and affects approximately 1% women under 40 years of age. Recent advances emphasize the genetic heterogeneity of POI. Fanconi anemia (FA) genes, traditionally known for their essential roles in DNA repair and cytogenetic instability, have been demonstrated to be involved in meiosis and germ cell development. Here, we conducted whole-exome sequencing (WES) in 50 Han Chinese female patients with POI. Rare missense variants were identified in FANCA (Fanconi anemia complementation group A): c.1772G > A (p.R591Q) and c.3887A > G (p.E1296G). Both variants are heterozygous in the patients and very rare in the human population. In vitro functional studies further demonstrated that these two missense variants of FANCA exhibited reduced protein expression levels compared with the wild type, suggesting the partial loss of function. Moreover, mono-ubiquitination levels of FANCD2 upon mitomycin C stimulation were significantly reduced in cells overexpressing FANCA variants. Furthermore, a loss-of-function mutation of Fanca was generated in C57BL/6 mice for in vivo functional assay. Consistently, heterozygous mutated female mice (Fanca+/-) showed reduced fertility and declined numbers of follicles with aging when compared with the wild-type female mice. Collectively, our results suggest that heterozygous pathogenic variants in FANCA are implicated in non-syndromic POI in Han Chinese women, provide new insights into the molecular mechanisms of POI and highlight the contribution of FANCA variants in female subfertility.

19.
Sci Total Environ ; 695: 133596, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31421330

RESUMO

Trace metal contamination prevails in various compartments of the urban environment. Understanding the roles of various anthropogenic sources in urban trace metal contamination is critical for pollution control and city development. In this study, the source contribution from various contamination sources to trace metal contamination (e.g., Cu, Pb, Zn, Co, Cr and Ni) in different environmental compartments in a typical megacity, Guangzhou, southern China, was investigated using the receptor model (Absolute Principal Component Scores-Multiple Linear Regression, APCS-MLR) coupled with the Kriging technique. Lead isotopic data and APCS-MLR analysis identified industrial and traffic emissions as the major sources of trace metals in surface soil, road dust, and foliar dust in Guangzhou. Lead isotopic compositions of road dust and foliar dust exhibited similar ranges, implying their similar sources and potential metal exchange between them. Re-suspended soil contributed to 0-38% and 25-58% of the trace metals in the road dust and foliar dust, respectively, indicating the transport of the different terrestrial dust. Spatial distribution patterns implied that Cu in the road dust was a good indicator of traffic contamination, particularly with traffic volume and vehicle speed. Lead and Zn in foliar dust indicated mainly industrial contamination, which decreased from the emission source (e.g., a power plant and steel factory) to the surrounding environment. The spatial influence of industry and traffic on the contamination status of road dust/foliar dust was successfully separated from that of other anthropogenic sources. This study demonstrated that anthropogenic inputs of trace metals in various environmental compartments (e.g., urban soil, road dust, and foliar dust) can be evaluated using a combined APCS-MLR receptor model and geostatistical analysis at a megacity scale. The coupled use of APCS-MLR analysis, geostatistics, and Pb isotopes successfully deciphered the spatial influence of the contamination sources in the urban environment matrix, providing some important information for further land remediation and health risk assessment.

20.
Ying Yong Sheng Tai Xue Bao ; 30(7): 2181-2190, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31418220

RESUMO

We used the mean annual temperature and mean annual precipitation data during 1961 and 2017 of 101 national meteorological stations in Yunnan Province to calculate three climate-induced potential productivity in Yunnan Province by Miami model and the Thornthwaite Memorial model. The abrupt test was carried out by Mann-Kendell method. The spatial and temporal distribution characteristics and future trends of the three climate-induced potential productivities were analyzed. Results showed that the average values of the temperature potential productivity (Yt), precipitation potential productivity (Yr) and evapotranspiration potential productivity (Ye) during the study period was 1968, 1477 and 1434 g·m-2·a-1, respectively. The value of Yt was rising in Yunnan Province. For the value of Yr /Yt, there was a large difference in water-heat ratio among regions, as well as the binding conditions. There was an abrupt change in climate-induced potential productivity, with Yt began to abrupt change significantly in 2001. There was no abrupt change in Yr, but Ye had abrupt change in 2002-2004. The spatial distribution of climate production potential and climate tendency were uneven. The annual average value of Yt, Yr and Ye was 1030-2465, 927-2341 and 832-1995 g·m-2·a-1, respectively. The climate-induced potential productivity was the lowest in the northwestern and northeastern Yunnan and the highest in the southwestern and southern Yunnan. Most of the climatic propensity rates of Yt, Yr and Ye showed increase, decrease and increase trends respectively. Eight schemes simulating future climate change (i.e., temperature increased by 1 ℃, precipitation increased by 10%, temperature decreased by 1 ℃, precipitation decreased by 10%, temperature increased by 1 ℃ and precipitation decreased by 10%, temperature increased by 1 ℃ and precipitation increased by 10%, the temperature decrease by 1 ℃ and the precipitation increased by 10%, the temperature decrease by 1 ℃ and precipitation decreased by 10%) would lead to Ye changes of 6-45, 13-77.2, 15-67, -87 to -17, -74-46, 58-96, -54-57, -101 to -59 g·m-2·a-1, respectively. On the whole, if the climate tends to be "warm and wet" in the future, it will be beneficial for crop production. However, if it tends to be "cold and dry", it will be unfavorable to crop production in the study area.


Assuntos
Mudança Climática , Ecossistema , China , Temperatura Ambiente , Água
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