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1.
Environ Pollut ; 260: 114084, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32041033

RESUMO

Northern China is a significant source of dust source in Central Asia. Thus, high-resolution analysis of dust storms and comparison of dust sources in different regions of northern China are important to clarify the formation mechanism of East Asian dust storms and predict or even prevent such storms. Here, we analyzed spatiotemporal trends in dust storms that occurred in three main dust source regions during 1960-2007: Taklimakan Desert (western region [WR]), Badain Jaran and Tengger Deserts (middle region [MR]), and Otindag Sandy Land (eastern region [ER]). We analyzed daily dust storm frequency (DSF) at the 10-day scale (first [FTDM], middle [MTDM], and last [LTDM] 10 days of a month), and investigated the association of dust storm occurrences with meteorological factors. The 10-day DSF was greatest in the FTDM (accounting for 77.14% of monthly occurrences) in the WR, MTDM (45.85%) in the MR, and LTDM (72.12%) in the ER, showing a clear trend of movement from the WR to the ER. Temporal analysis of DSF revealed trend changes over time at annual and 10-day scales, with mutation points at 1985 and 2000. We applied single-factor and multiple-factor analyses to explore the driving mechanisms of DSF at the 10-day scale. Among single factors, a low wind-speed threshold, high solar radiation, and high evaporation were correlated with a high DSF, effectively explaining the variations in DSF at the 10-day scale; however, temperature, relative humidity, and precipitation poorly explained variations in DSF. Similarly, multiple-factor analysis using a classification and regression tree revealed that maximum wind speed was a major influencing factor of dust storm occurrence at the 10-day scale, followed by relative humidity, evaporation, and solar radiation; temperature and precipitation had weak influences. These findings help clarify the mechanisms of dust storm occurrence in East Asia.

2.
Am J Sports Med ; 48(3): 554-564, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31967861

RESUMO

BACKGROUND: Graft healing within the femoral tunnel after anterior cruciate ligament reconstruction (ACLR) using suspensory fixation could be reflected in graft maturation and tunnel morphological changes. However, the correlation between graft maturation and femoral tunnel changes remains unclear. PURPOSE: To quantitatively evaluate femoral tunnel morphological changes and graft maturation and to analyze their correlation after ACLR using femoral cortical suspension. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Patients who underwent single-bundle ACLR with a hamstring tendon autograft using femoral cortical suspension were included. Preoperative and postoperative (at 6, 12, and 24 months) knee function were evaluated using KT-1000 arthrometer testing, the Lysholm knee scoring scale, and the International Knee Documentation Committee (IKDC) questionnaire. At 1 day, 6 months, 12 months, and 24 months after ACLR, 3-dimensional magnetic resonance imaging was performed to observe the morphology of the femoral tunnel and to evaluate graft maturation using the graft signal/noise quotient (SNQ). The Pearson product moment correlation coefficients (r) of femoral tunnel radii versus clinical outcomes and graft SNQs at last follow-up were analyzed. RESULTS: A total of 22 patients completed full follow-up. KT-1000 arthrometer, Lysholm, and IKDC scores improved over time postoperatively, but no significant improvement was seen after 12 months (P < .05). The radius of the tunnel containing the graft and the SNQs of the femoral intraosseous graft and intra-articular graft were the highest at 6 months, and they decreased by 24 months but remained higher than their 1-day postoperative values (P < .05). Expansion mainly occurred at the anteroinferior wall of the femoral tunnel. The tunnel aperture radius was positively correlated with SNQs of the intraosseous graft (r = 0.591; P < .05) and intra-articular graft (r = 0.359; P < .05) but not with clinical outcomes. CONCLUSION: After ACLR using suspensory fixation, morphological changes of the femoral tunnel were mainly observed in the part of the tunnel containing the graft, which expanded at 6 months and reduced by 24 months. Expansion mainly occurred at the anteroinferior wall of the femoral tunnel. Femoral tunnel expansion was correlated with inferior graft maturation but not with clinical outcomes.

3.
Eur Radiol ; 30(3): 1470-1479, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31748853

RESUMO

OBJECTIVES: Antibodies to myelin oligodendrocyte glycoprotein (MOG-ab) and antibodies to aquaporin-4 (AQP4-ab) have been suggested to play roles in commonly separated subsets of patients with neuromyelitis optica spectrum disorder (NMOSD) phenotypes. The aim of this study is to quantitatively delineate and compare the brain lesion distributions of AQP4-ab-positive and MOG-ab-positive patients. METHODS: Fifty-seven and twenty-eight clinical MRI scans were collected from fifty-two AQP4-ab-positive and twenty-four MOG-ab-positive patients, respectively. T2 lesions were segmented manually on each axial FLAIR image. Probabilistic lesion distribution maps were created for each group after spatial normalization. Lobe-wise and voxel-wise quantitative comparisons of the two distributions were performed. A classification model based on the lesion distribution features was constructed to differentiate the two patient groups. RESULTS: Infratentorial and supratentorial brain lesions were found in both AQP4-ab-positive and MOG-ab-positive patients, with large inter-group overlap mainly in deep white matter (WM). In comparison with those in the AQP4 group, the brain lesions of the MOG-ab-positive patients had a larger size, dispersed distribution, and higher probabilities in the cerebellum, pons, midbrain, and GM and juxtacortical WM in temporal, sublobar, frontal, and parietal lobes. The area under the receiver operating characteristic curve of the lesion-distribution-based classification model was 0.951. CONCLUSIONS: MOG-ab-positive and AQP4-ab-positive groups showed similar but quantitatively different brain lesion distributions. These results may help clinicians in considering MOG versus AQP4 in initial diagnosis, and add rationale for sending corresponding serologic testing. KEY POINTS: • Brain lesion distributions of AQP-ab-positive and MOG-ab-positive NMOSD patients • Larger size, dispersed distribution, higher lesion probabilities in the cerebellum, pons, midbrain, and GM and juxtacortical WM in the MOG group • The lesion-distribution-based classification model differentiates the two groups with AUC = 0.951.

4.
Virol J ; 16(1): 136, 2019 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-31727103

RESUMO

BACKGROUND: Goose parvovirus (GPV) is the etiological agent of Derzsy's disease and is fatal for gosling. Research on the molecular basis of GPV pathogenicity has been hampered by the lack of a reliable reverse genetics system. At present, the GPV infectious clone has been rescued by transfection in the goose embryo, but the growth character of it is unclear in vitro. METHODS: In this study, we identified the full-length genome of GPV RC16 from the clinical sample, which was cloned into the pACYC177, generating the pIRC16. The recombinant virus (rGPV RC16) was rescued by the transfection of pIRC16 into goose embryo fibroblasts (GEFs). The rescued virus was characterized by whole genome sequencing, indirect immunofluorescence assays (IFA) and western blot (WB) using rabbit anti-GPV Rep polyclonal antibody as the primary antibody. Previously, we found the 164 K, 165 K, and 167 K residues in the 160YPVVKKPKLTEE171 are required for the nuclear import of VP1 (Chen S, Liu P, He Y, et al. Virology 519:17-22). According to that, the GPV infectious clones with mutated K164A, K165A, or K167A in VP1 were constructed, rescued and passaged. RESULTS: The rGPV RC16 has been successfully rescued by transfection of pIRC16 into the GEFs and can proliferate in vitro. Furthermore, the progeny virus produced by pIRC16 transfected cells was infectious in GEFs. Moreover, mutagenesis experiments showed that the rGPV RC16 with mutated 164 K, 165 K and 167 K in VP1 could not proliferate in GEFs based on the data of IFA and WB in parental virus and progeny virus. CONCLUSIONS: The rGPV RC16 containing genetic maker and the progeny virus are infectious in GEFs. The 164 K, 165 K, and 167 K of VP1 are vital for the proliferation of rGPV RC16 in vitro.

5.
Sci Total Environ ; 697: 134126, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31491630

RESUMO

Heavy metals in agricultural soil receive much attention because they are easily absorbed by crop into the ecosystem. Managing the discharge of heavy metals from the source is an effective way to prevent and control heavy metals pollution. Grouped principal component analysis (GPCA) and Positive Matrix Factorization (PMF) receptor models were utilized in this study to conduct source apportionment, and the former was optimal because of the accuracy of predicting. Based on the source contribution by GPCA/APCS, heavy metals were evaluated by fuzzy synthetic evaluation model and health risk assessment model. The results of source apportionment showed that heavy metals in Zhangye agricultural soil were mainly affected by steel industry, traffic, agrochemicals, manures, mining activities, leather industry and metal processing industry source. Fuzzy synthetic evaluation showed that the pollution levels of Chromium (Cr) derived by leather industry and metal processing industry and Nickel (Ni) derived by steel industry and traffic source were higher. Health risk assessment revealed that the non-carcinogenic and carcinogenic risks of Cr derived by leather industry and metal processing industry and Lead (Pb) derived by steel industry and traffic source were higher.


Assuntos
Monitoramento Ambiental , Poluição Ambiental/estatística & dados numéricos , Metais Pesados/análise , Poluentes do Solo/análise , China , Lógica Fuzzy , Análise Multivariada , Medição de Risco
6.
Mol Biol Evol ; 36(8): 1643-1652, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31112995

RESUMO

A general south-north genetic divergence has been observed among Han Chinese in previous studies. However, these studies, especially those on mitochondrial DNA (mtDNA), are based either on partial mtDNA sequences or on limited samples. Given that Han Chinese comprise the world's largest population and reside around the whole China, whether the north-south divergence can be observed after all regional populations are considered remains unknown. Moreover, factors involved in shaping the genetic landscape of Han Chinese need further investigation. In this study, we dissected the matrilineal landscape of Han Chinese by studying 4,004 mtDNA haplogroup-defining variants in 21,668 Han samples from virtually all provinces in China. Our results confirmed the genetic divergence between southern and northern Han populations. However, we found a significant genetic divergence among populations from the three main river systems, that is, the Yangtze, the Yellow, and the Zhujiang (Pearl) rivers, which largely attributed to the prevalent distribution of haplogroups D4, B4, and M7 in these river valleys. Further analyses based on 4,986 mitogenomes, including 218 newly generated sequences, indicated that this divergence was already established during the early Holocene and may have resulted from population expansion facilitated by ancient agricultures along these rivers. These results imply that the maternal gene pools of the contemporary Han populations have retained the genetic imprint of early Neolithic farmers from different river basins, or that river valleys represented relative migration barriers that facilitated genetic differentiation, thus highlighting the importance of the three ancient agricultures in shaping the genetic landscape of the Han Chinese.


Assuntos
Genoma Humano , Genoma Mitocondrial , Rios , Agricultura , China , Demografia , Humanos , Filogeografia
7.
J Environ Manage ; 243: 137-143, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31096168

RESUMO

With the rapid and extensive development of industry and agriculture, the soil environment inevitably becomes contaminated with heavy metals, thus creating adverse environmental conditions for flora and fauna. The traditional methods for combining field sampling with laboratory analysis of soil heavy metals are limited not only because they are time-consuming and expensive, but also because they are unable to obtain adequate information about the spatial distribution characteristics of heavy metals in soil over a large area. Three hundred and ninety-four soil samples (Gobi and farmland) were collected in an arid area in Jiuquan in Northwest China and analyzed for elements concentrations. Based on these measured concentrations, as well as rapid and environmentally friendly remote sensing (multi-spectral data), stepwise multiple linear regression (SMLR) and partial least-squares regression (PLS) were combined to predict concentrations and distributions of heavy metals in the soils of the study area. Furthermore, laboratory data were used to assess the accuracy of the prediction results. Obtained results suggest that the SMLR and PLS models were able to predict the metals contents in the study area. The concentrations of Cr, Ni, V and Zn could be predicted by two regression models, while those of Cu and Mn were predicted more accurately when they were attached to the SMLR model. The spatial distribution of heavy metals derived from the two models is consistent with measured values, indicating that it is reasonable to predict the concentrations of heavy metals in the soil of the study area using the multi-spectral data.


Assuntos
Metais Pesados , Poluentes do Solo , China , Monitoramento Ambiental , Solo
8.
PeerJ ; 7: e6555, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30886771

RESUMO

Background: Adrenocortical carcinoma (ACC) is a rare and aggressive malignant cancer in the adrenal cortex with poor prognosis. Though previous research has attempted to elucidate the progression of ACC, its molecular mechanism remains poorly understood. Methods: Gene transcripts per million (TPM) data were downloaded from the UCSC Xena database, which included ACC (The Cancer Genome Atlas, n = 77) and normal samples (Genotype Tissue Expression, n = 128). We used weighted gene co-expression network analysis to identify gene connections. Overall survival (OS) was determined using the univariate Cox model. A protein-protein interaction (PPI) network was constructed by the search tool for the retrieval of interacting genes. Results: To determine the critical genes involved in ACC progression, we obtained 2,953 significantly differentially expressed genes and nine modules. Among them, the blue module demonstrated significant correlation with the "Stage" of ACC. Enrichment analysis revealed that genes in the blue module were mainly enriched in cell division, cell cycle, and DNA replication. Combined with the PPI and co-expression networks, we identified four hub genes (i.e., TOP2A, TTK, CHEK1, and CENPA) that were highly expressed in ACC and negatively correlated with OS. Thus, these identified genes may play important roles in the progression of ACC and serve as potential biomarkers for future diagnosis.

9.
Sci Total Environ ; 660: 947-958, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30743979

RESUMO

Four main dust sources and dust events that affected the Hexi Corridor were defined, and the HYSPLIT model was used to trace the dust that originated during the dust episodes of 2015-2017 and to quantify the contributions of dust sources to PM10. On this basis, an algorithm that quantified the contribution of dust sources to PM10 was proposed in this study. The results showed that the main dust sources affecting the Hexi Corridor are generally located in the northern part of Xinjiang, which is mainly dominated by the Gurbantunggut Desert (source A); the Taklimakan and Kumtag Deserts and their surrounding areas (source B); both Qaidam Basins (source C); and the Badain Jaran Desert, Tengger Desert, Hobq Desert, Ulan Buh Desert, and Mu Us Sandy Land and their surrounding areas (source D). The occurrence time of dust and the frequency of PM10 exceeded the daily concentration standards and showed significant characteristics of being high in the spring and low in the autumn. The higher concentration of PM10 in the winter was mainly due to anthropogenic sources from heating process. The contribution of source area D to PM10 concentration was the greatest (42%). Source area B was one of the main dust sources (with a contribution rate of 23%); however, approximately 63% of the dust in this area originates from the Kumtag Desert. The contribution of source area A is lower than that of the study area due to greater precipitation and higher vegetation coverage (22% contribution rate). Source area C has the lowest contribution to the research area due to obstruction by the Qilian Mountain (13% contribution rate).

10.
Parkinsonism Relat Disord ; 62: 134-140, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30635245

RESUMO

INTRODUCTION: The pathophysiologic mechanism of paroxysmal kinesigenic dyskinesia (PKD) is largely unclear. Basal ganglia-thalamo-cortical circuit involvement is thought to underlie PKD pathophysiology. However, microstructural alternations in the motor circuit of PKD require further elucidation. METHODS: Diffusion tensor imaging and high-resolution T1-weighted imaging were performed on 30 PKD patients (15 PRRT2 carriers, 15 PRRT2 non-carriers) and 15 matched healthy controls. Tract-based spatial statistics were conducted on diffusion indices to examine microstructural integrity of white matter. Voxel-based morphometry analysis was used to examine volumetric changes of gray matter. Multiple regression was employed to test the contribution of demography, disease duration, and PRRT2 status to pathological changes in brain structure. RESULTS: Six (including two novel) PRRT2 mutations were identified in PKD patients who exhibited significantly reduced mean diffusivity mainly along the left corticospinal tract, and reduced gray matter volume in pre-supplementary motor area (preSMA) and right opercular part of inferior frontal gyrus (IFGoperc), compared to healthy controls. Both gray matter volume reductions in preSMA and diffusion indices of abnormal white matter negatively correlated with disease duration. Genotype-phenotype analysis revealed that PRRT2 mutation carriers had earlier onset age, longer attacks, and a larger proportion of bilateral symptoms than non-carriers. CONCLUSIONS: We observed that PRRT2 mutations were associated with disease severity, while neuroanatomical abnormality was associated with disease duration in patients with PKD. Aberrant microstructural changes in preSMA and IFG areas, independent of mutation status, point to dysregulated motor inhibition in patients and provide new insights into neurobiological mechanisms underlying motor symptoms of PKD.

11.
Clin Neuroradiol ; 29(2): 321-329, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29464268

RESUMO

PURPOSE: To investigate the cerebral macrovascular changes as well as the relationship of large vessels and cerebral blood flow (CBF) in mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (MELAS) using magnetic resonance angiography (MRA) and arterial spin labeling (ASL) perfusion MR imaging (MRI). METHODS: A total of 20 patients diagnosed with MELAS (12 males, 8 females; mean age, 23.3 years) underwent conventional MRI, time-of-flight (TOF) MRA and three dimensional ASL. Follow-up scans were performed in 10 patients. The changes of cerebral arteries and branches on MRA images from both acute and recovery patients were independently evaluated by two radiologists. Lesion distribution and CBF were observed on the integrated maps of MRA and ASL. RESULTS: In 14 patients with clinical onsets, increased CBF was observed in all stroke-like lesions. Dilations of a single artery (four middle cerebral arteries, two posterior cerebral arteries) were found in six patients. Dilations of multiple arteries (two anterior cerebral arteries, seven middle cerebral arteries, six posterior cerebral arteries) were found in seven patients. Normal angiography was shown in one acute patient. Cortical terminal branches feeding the lesion areas were more obviously dilated than the main trunks. The dilated vessels returned to normal on follow-up scans concurrently with decreased CBF in nine patients who were resuscitated from episode attacks. Vasodilation was even seen in one preclinical patient who suffered a recurrent episode 50 days later. CONCLUSION: Reversible dilation of cerebral macrovascular changes could be a new feature of MELAS and a presumed reason for fluctuant CBF. It would shed new light on the mitochondrial angiopathy.


Assuntos
Doenças Arteriais Cerebrais/patologia , Síndrome MELAS/patologia , Doença Aguda , Doenças Arteriais Cerebrais/fisiopatologia , Circulação Cerebrovascular/fisiologia , Constrição Patológica/patologia , Constrição Patológica/fisiopatologia , Feminino , Humanos , Síndrome MELAS/fisiopatologia , Angiografia por Ressonância Magnética/métodos , Masculino , Artéria Cerebral Média/patologia , Artéria Cerebral Média/fisiologia , Artéria Cerebral Posterior/patologia , Artéria Cerebral Posterior/fisiologia , Estudos Prospectivos , Vasodilatação/fisiologia , Adulto Jovem
12.
Neuroscience ; 397: 12-17, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30500612

RESUMO

This study aimed to investigate the cortical functional alterations in patients with unilateral facial synkinesis using the task-designed functional magnetic resonance imaging. Fourteen unilateral synkinesis followed by peripheral facial nerve palsy patients and eighteen healthy adults were recruited in this study. Four facial motor tasks, i.e. left/right blinking and left/right smiling, were performed by each subject during the scans. Based on the activation maps, the spatial distance between the representation sites in the contralateral pre-/post-central gyrus of left or right blinking and smiling tasks (i.e. left/right B-S-distance) were calculated. Patients with unilateral facial synkinesis showed decreased B-S-distances during blinking and smiling tasks on the affected half face (9.68 ±â€¯3.92 mm) compared to both average distances in healthy controls (14.95 ±â€¯5.55 mm; p = 0.002) and unaffected half face tasks in patients (16.19 ±â€¯7.87 mm; p = 0.011). These findings demonstrated cortical reorganization in facial synkinesis and suggested a conceivable mechanism corresponding to the simultaneous facial movement. This potentially provides a new modulation target for preventive, therapeutic and rehabilitative maneuver of this disease.


Assuntos
Piscadela/fisiologia , Encéfalo/fisiopatologia , Doenças do Nervo Facial/fisiopatologia , Sorriso/fisiologia , Sincinesia/fisiopatologia , Adulto , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Doenças do Nervo Facial/diagnóstico por imagem , Feminino , Lateralidade Funcional , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Sincinesia/diagnóstico por imagem
13.
Genome Res ; 28(11): 1601-1610, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30352807

RESUMO

Centenarians (CENs) are excellent subjects to study the mechanisms of human longevity and healthy aging. Here, we analyzed the transcriptomes of 76 centenarians, 54 centenarian-children, and 41 spouses of centenarian-children by RNA sequencing and found that, among the significantly differentially expressed genes (SDEGs) exhibited by CENs, the autophagy-lysosomal pathway is significantly up-regulated. Overexpression of several genes from this pathway, CTSB, ATP6V0C, ATG4D, and WIPI1, could promote autophagy and delay senescence in cultured IMR-90 cells, while overexpression of the Drosophila homolog of WIPI1, Atg18a, extended the life span in transgenic flies. Interestingly, the enhanced autophagy-lysosomal activity could be partially passed on to their offspring, as manifested by their higher levels of both autophagy-encoding genes and serum beclin 1 (BECN1). In light of the normal age-related decline of autophagy-lysosomal functions, these findings provide a compelling explanation for achieving longevity in, at least, female CENs, given the gender bias in our collected samples, and suggest that the enhanced waste-cleaning activity via autophagy may serve as a conserved mechanism to prolong the life span from Drosophila to humans.


Assuntos
Autofagia/genética , Longevidade/genética , Transcriptoma , Idoso , Idoso de 80 Anos ou mais , Proteínas Relacionadas à Autofagia/genética , Proteínas Relacionadas à Autofagia/metabolismo , Proteína Beclina-1/genética , Proteína Beclina-1/metabolismo , Catepsina B/genética , Catepsina B/metabolismo , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/metabolismo , Feminino , Humanos , Lisossomos/metabolismo , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Pessoa de Meia-Idade , ATPases Vacuolares Próton-Translocadoras/genética , ATPases Vacuolares Próton-Translocadoras/metabolismo
14.
Ann Bot ; 122(7): 1245-1262, 2018 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-30084909

RESUMO

Background and Aims: The role played by the Qinghai-Tibet Plateau (QTP) in the organismal diversification and biogeography of plants in the Northern Hemisphere has attracted much attention from evolutionary biologists. Here we use tribe Lilieae (Liliaceae), including primarily temperate and alpine lineages with disjunct distributions in the North Temperate Zone, as a case study to shed light upon these processes. Methods: Using 191 taxa (five outgroup taxa) comprising more than 60 % of extant Lilieae species across the entire geographical range, we analyse phylogenetic relationships based on three plastid markers (matK, rbcL, rpl16) and nuclear ITS. Divergence time estimation and ancestral range reconstruction were further inferred. Key Results: The results support a monophyletic Lilieae divided into four clades. Lilium is nested within Fritillaria, which is paraphyletic and partitioned into two clades, New World and Old World, in the chloroplast DNA (cpDNA) analysis. Incongruences between the ITS and cpDNA trees may be explained by divergent ITS paralogues and hybridization. Lilieae originated around 40-49 (28-67) Mya and probably diversified in the QTP region with four major clades that were established during the Oligocene and the Early Miocene. Uplift of the QTP and climatic changes probably drove early diversification of Lilieae in the QTP region. A rapid radiation occurred during the Late Miocene and the Pleistocene, coinciding temporally with recent orogenic process in the QTP region and climatic oscillations. Several lineages dispersed out of the QTP. Conclusions: Lineage persistence and explosive radiation were important processes for establishing high species diversity of Lilieae in the QTP region. Both long-distance dispersal and migration across Beringia probably contributed to the modern distribution range of Lilieae. Our study shows that biotic interchanges between the QTP region and Irano-Turanian region and the Mediterranean Basin were bi-directional, suggesting the latter was a secondary centre of diversity.


Assuntos
Biodiversidade , Liliaceae/classificação , Liliaceae/fisiologia , Filogenia , Dispersão Vegetal , Evolução Biológica , DNA de Cloroplastos/análise , Liliaceae/genética , Filogeografia
15.
Eur Radiol ; 28(12): 4940-4948, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29948064

RESUMO

OBJECTIVES: To explore the sensitivity of potential DTI-based biomarkers in detecting microstructural changes for whole-brain white matter in early stage amyotrophic lateral sclerosis (ALS), analyze the relationship between the DTI indices and disease status, and further clarify potential brain regions for disease monitoring and clinical assessment. METHODS: Thirty-three non-demented ALS patients and 32 age- and gender-matched subjects participated in this study. DTI data were acquired via 3.0T MRI scanner. Maps of diffusion-related indices including fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) were obtained. Tract-based spatial statistics (TBSS) were used to investigate whole-brain white matter changes of each index. Correlation analyses between both brain-wide and volume-of-interest (VOI)-wide white matter alterations and clinical factors including ALSFRS-R scores, disease duration, and progression rate were performed. RESULTS: Compared to healthy subjects, ALS patients showed significantly increased RD, MD and reduced FA, mainly along the corticospinal tract (CST) and the body of corpus callosum (CC). Increases in RD were broader than decreases in FA, in CST of both hemispheres. Meanwhile, involvement of several extra-motor regions was also revealed by RD. Significant positive correlation between ALSFRS-R scores and FA, negative correlation between ALSFRS-R and RD were found in left CST. CONCLUSIONS: RD may be the most sensitive biomarker for the detection of early demyelination of white matter. Both RD and FA may serve as objective biomarkers for disease severity assessment. CST may be the most affected brain region in non-demented ALS. KEY POINTS: • Changes in RD were broader than those in FA in bilateral CST. • Involvement of extra-motor regions was uncovered by RD. • FA and RD in CST were related to ALSFRS-R scores.


Assuntos
Esclerose Amiotrófica Lateral/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Substância Branca/diagnóstico por imagem , Adulto , Idoso , Anisotropia , Biomarcadores , Estudos de Casos e Controles , Doenças Desmielinizantes/diagnóstico por imagem , Difusão , Diagnóstico Precoce , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
16.
J Environ Manage ; 222: 95-103, 2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-29804037

RESUMO

PM10 and PM2.5 concentration data were collected from five air-quality monitoring sites in Lanzhou from October 2014 to October 2015, revealing the spatial-temporal behavior of local particulate matter (PM). The Hybrid Single Particle Lagrangian Integrated Trajectory Model (HYSPLIT) and the PM2.5-to-PM10 ratio model were used to investigate the primary transport path, potential source areas and contributions of the East Asian sandstorm to PM in Lanzhou. The analysis in three functional areas of the city indicated that the monthly variation in PM2.5 displayed a unimodal U pattern (the highest value was during the heating period), whereas that of PM10 displayed a bimodal pattern (the primary peak appeared in the spring, and the secondary peak appeared in the winter). These two patterns originated from different PM sources. The PM2.5 was primarily affected by human activities, and the PM10 was influenced by both natural and anthropogenic activities, but the relative contributions of these activities were associated with spatial-temporal variations. The daily PM10 and PM2.5 concentration variations displayed a bimodal pattern in the three functional areas: the peak values appeared at 11:00-13:00 and 22:00-1:00, respectively, and the lowest values appeared at 4:00-6:00 and 16:00-18:00, respectively. On the monthly, seasonal and daily scales, the PM concentrations exhibited similar patterns in the industrial, urban and rural areas, indicating that they were partly controlled by the regional natural environment. Meanwhile, due to anthropogenic factors, considerable PM amounts were discharged into the external environment, leading to maximum and minimum concentrations of PM appearing in the industrial and rural areas, respectively. The HYSPLIT model showed that dust storms from the northwest desert and Gobi regions affected Lanzhou three times in March 2015 and contributed 68% and 40% of the total mass of PM10 and PM2.5, respectively.


Assuntos
Poluentes Atmosféricos , Cidades , Monitoramento Ambiental , China , Poeira , Humanos , Minerais , Tamanho da Partícula , Material Particulado , Estações do Ano
17.
Environ Sci Pollut Res Int ; 25(23): 22606-22618, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29845550

RESUMO

Rapid and extensive social and economic development has caused severe soil contamination by heavy metals in China. The spatial distribution, pollution levels, and health risks of metals were identified in an oasis-desert zone of northwest China. The mean concentrations of six heavy metals exceeded their corresponding background contents, and each metal concentration in farmland samples was higher than that in Gobi samples. Moreover, these heavy metals followed a similar spatial pattern and showed significant positive correlations with each other, indicating that they have the same sources. The contamination features of heavy metals and ecological risks were calculated using several quality indicators, and their health risks for population groups were quantified. The results showed that the Gobi and farmland soils were uncontaminated to moderately contaminated by heavy metals, and that farmland pollution was more serious than that of Gobi. The Gobi and farmland soils posed low ecological risks. As a whole, the non-carcinogenic risk which was caused by heavy metals was low for local residents, and the carcinogenic risk was within an acceptable level. Comparatively speaking, children were the more vulnerable population to health risks. The Zn and Cu pollution was relatively serious, and Cr and V were major contributors to health risks. Graphical abstract ᅟ.


Assuntos
Monitoramento Ambiental , Metais Pesados/análise , Poluentes do Solo/análise , Criança , China , Clima Desértico , Exposição Ambiental , Humanos , Medição de Risco
18.
Environ Pollut ; 230: 189-198, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28651090

RESUMO

To investigate the spatial and temporal behaviors of particulate matter in Lanzhou, Jinchang and Jiayuguan during 2014, the hourly concentrations of PM2.5 and PM10 were collected from the Ministry of Environmental Protection (MEP) in this study. The analysis indicated that the mean annual PM10 (PM2.5) concentrations during 2014 were 115 ± 52 µg/m3 (57 ± 28 µg/m3), 104 ± 75 µg/m3 (38 ± 22 µg/m3) and 114 ± 72 µg/m3 (32 ± 17 µg/m3) in Lanzhou, Jinchang and Jiayuguan, respectively, all of which exceeded the Chinese national ambient air quality II standards for PM. Higher values for both PM fractions were generally observed in spring and winter, and lower concentrations were found in summer and autumn. Besides, the trend of seasonal variation of particulate matter (PM) in each city monitoring site is consistent with the average of the corresponding cities. Anthropogenic activities along with the boundary layer height and wind scale contributed to diurnal variations in PM that varied bimodally (Lanzhou and Jinchang) or unimodally (Jiayuguan). With the arrival of dust events, the PM10 concentrations changed dramatically, and the PM10 concentrations during dust storm events were, respectively, 19, 43 and 17 times higher than the levels before dust events in Lanzhou, Jinchang and Jiayuguan. The ratios (PM2.5/PM10) were lowest, while the correlations were highest, indicating that dust events contributed more coarse than fine particles, and the sources of PM are similar during dust storms. The relationships between local meteorological parameters and PM concentrations suggest a clear association between the highest PM concentrations, with T ≤ 7 °C, and strong winds (3-4 scale). However, the effect of relative humidity is complicated, with more PM10 and PM2.5 exceedances being registered with a relative humidity of less than 40% and 40-60% in Lanzhou, while higher exceedances in Jinchang appeared at a relative humidity of 80-100%.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Monitoramento Ambiental , Material Particulado/análise , China , Cidades , Poeira/análise , Meteorologia , Estações do Ano , Vento
19.
Ann Bot ; 119(1): 59-72, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27941092

RESUMO

BACKGROUND AND AIMS: The patterns of evolutionary assembly in the Sino-Japanese floristic region (SJFR) remain largely unknown due to a lack of integrative multidimensional studies throughout the region. To address this issue, we elucidated the evolutionary history of Cardiocrinum (Liliaceae), a genus containing four taxa distributed across the SJFR. METHODS: Fifty-four populations were sampled throughout the geographical range of Cardiocrinum to assess genetic structure, analyse phylogenetic relationships and reconstruct ancestral area based on six chloroplast DNA (cpDNA) fragments and three low copy nuclear genes (LCNG). Ecological niche modelling was used to examine the potential range shifts of Cardiocrinum in response to climatic change. KEY RESULTS: The molecular data showed high genetic similarity in the cpDNA (98·37 %) and LCNG (94·53 %) sequences. The biogeographical analyses revealed that the ancestor of Cardiocrinum diversified during the late Miocene (approx. 7·32 Mya) in Central China. The ancestor of the C. giganteum lineage dispersed westward to the Himalayas and south-west China with the split between C. giganteum and C. giganteum var. yunnanense occurring around 4·11 Mya consistent with the period of orogeny of the Hengduan Mountains. Some populations of the C. cathayanum lineage dispersed eastward to south Japan via the land bridge approx. 4·97 Mya, providing opportunities for allopatric speciation of C. cordatum The predicted suitable habitats of Cardiocrinum have become smaller and more fragmented since the Last Glacial Maximum. CONCLUSIONS: Our study provides evidence of a biogeographical pattern of dispersal from Central China to the Himalayas in the west and Japan in the east for genera distributed across the SJFR, and highlights that the orogeny of the Hengduan Mountains and fluctuations of the sea level of the East China Sea played important roles in promoting species divergence.


Assuntos
Liliaceae/genética , Evolução Biológica , China , DNA de Plantas/genética , Ecossistema , Variação Genética/genética , Japão , Filogenia , Filogeografia , Análise de Sequência de DNA
20.
Sci Rep ; 6: 21962, 2016 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-26911903

RESUMO

Centenarians are a good healthy aging model. Interestingly, centenarians' offspring are prone to achieve longevity. Here we recruited 60 longevity families and investigated the blood biochemical indexes of family members to seek candidate factors associated with familial longevity. First, associations of blood indexes with age were tested. Second, associations of blood parameters in centenarians (CEN) with their first generation of offspring (F1) and F1 spouses (F1SP) were analyzed. Third, genes involved in regulating target factors were investigated. We found that total cholesterol (TC) and triglyceride (TG) increased with age (20-80 years), but decreased in CEN. Similarly, blood urea nitrogen (BUN) and blood creatinine (BCr) increased with age (20-80 years), but were maintained on a plateau in CEN. Importantly, we first revealed dual changes in blood pressure, i.e., decreased diastolic blood pressure but increased systolic blood pressure in CEN, which associated with altered CST3 expression. Genetic analysis revealed a significant association of blood uric acid (BUA) and BCr in CEN with F1 but not with F1SP, suggesting they may be heritable traits. Taken together, our results suggest serum lipids, kidney function and especially diastolic pressure rather than systolic pressure were improved in CEN or their offspring, suggesting these factors may play an important role in familial longevity.


Assuntos
Pressão Sanguínea/fisiologia , Rim/metabolismo , Lipídeos/sangue , Longevidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Grupo com Ancestrais do Continente Asiático , Nitrogênio da Ureia Sanguínea , China , Colesterol/sangue , Creatinina/sangue , Cistatina C/metabolismo , Humanos , Testes de Função Renal , Metabolismo dos Lipídeos/genética , Masculino , Pessoa de Meia-Idade , Transcriptoma , Triglicerídeos/sangue , Ácido Úrico/sangue
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