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1.
J Craniofac Surg ; 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-32209934

RESUMO

Hemangiomas are relatively rare tumors representing approximately 0.4% of all the salivary gland tumors and occur predominantly in the parotid. Most of the hemangiomas appear during the first year of life; however, are uncommon in adults. Moreover, the rich fat hemangiomas in the parotid are extremely rare. Magnetic resonance imaging is the most important radiologic methods for the diagnosis of the disease as its high resolution of soft tissue which helps to show the relationship with the adjacent structures.

2.
Curr Med Sci ; 40(1): 123-129, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32166674

RESUMO

Albiziae Flos (AF) has been experimentally proven to have an antidepressant effect. However, due to the complexity of botanical ingredients, the exact pharmacological mechanism of action of AF in depression has not been completely deciphered. This study used the network pharmacology method to construct a component-target-pathway network to explore the active components and potential mechanisms of action of AF. The methods included collection and screening of chemical components, prediction of depression-associated targets of the active components, gene enrichment, and network construction and analysis. Quercetin and 4 other active components were found to exert antidepressant effects mainly via monoaminergic neurotransmitters and cAMP signaling and neuroactive ligand-receptor interaction pathways. DRD2, HTR1A, and SLC6A4 were identified as important targets of the studied bioactive components of AF. This network pharmacology analysis provides guidance for further study of the antidepressant mechanism of AF.

3.
Artigo em Inglês | MEDLINE | ID: mdl-32187779

RESUMO

Very recently, hydrovoltaic technology is emerging as a novel renewable energy harvesting method through carefully controlling the interaction between water and solid surface, which dramatically extends the capability to harvest water energy. However, the urgent issue restricting its device performance is poor carrier transport properties of the solid surface if large charged interface is considered simultaneously. Here, a hydrovoltaic device based on silicon nanowire arrays (SiNWs), which provide large charged surface/volume ratio and excellent carrier transport properties simultaneously, yields sustained electricity via carrier concentration gradient induced by evaporation-induced water flow inside nanochannels. And a device can yield direct current with a short-circuit current density of over 55 µA/cm 2 , which is three orders larger than previous reported analogous device (approximately 40 nA/cm 2 ). In addition, this device exhibits a constant output power density of over 6 µW/cm 2 and an open-circuit voltage of up to 400 mV, which enables it to easily drive a commercial light emitting diode. We also demonstrate the potential application of this electrokinetic phenomenon by using it to create a breathing sensor. Through changing ion concentration in water, length and surface charge of SiNWs, we propose the mechanism of harvesting energy through water flow in SiNWs. Our findings reveal that the generated energy should be mainly correlated with Debye screening effect and Coulomb interactions. Our finding may pave a way for developing innovative energy-harvesting devices from ubiquitous evaporation-driven internal water flow in nature with semiconductor material of silicon.

4.
BMC Complement Med Ther ; 20(1): 88, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32178661

RESUMO

BACKGROUND: Sedum sarmentosum is traditionally used to treat various inflammatory diseases in China. It has protective effects against acute liver injury, but the exact mechanism of such effects remains unclear. This study investigated the protective effects of S. sarmentosum extract on lipopolysaccharide (LPS)/D-galactosamine (D-GalN)-induced acute liver injury in mice and the mechanism of such effects. METHODS: Mice were randomly divided into control, treatment, model, and model treatment groups. Acute liver injury was induced in model mice via intraperitoneal injection of LPS and D-GalN with doses of 10 µg/kg of LPS and 500 mg/kg, respectively. The mRNA expression levels of miR-124, Hedgehog, Patched (Ptch), Smoothened (Smo), and glioma-associated oncogene homolog (Gli) in liver tissues were determined through RT-PCR, and the protein levels of Hedgehog, Ptch, Smo, Gli, P13k, Akt, HMGB1, TLR4, IkB-α, p-IkB-α, and NF-kB65 were evaluated via Western blot analysis. The serum levels of IL-6, TNF-α, CRP, IL-12, and ICAM-1 were determined via ELISA. TLR4 and NF-κBp65 activity and the levels of DNA-bound NF-KB65 and TLR4 in LPS/D-GalN-induced liver tissues were also determined. We recorded the time of death, plotted the survival curve, and calculated the liver index. We then observed the pathological changes in liver tissue and detected the levels of liver enzymes (alanine aminotransferase [ALT] and aspartate transaminase [AST]) in the serum and myeloperoxidase (MPO) and plasma inflammatory factors in the liver homogenate. Afterward, we evaluated the protective effects of S. sarmentosum extracts on acute liver injury in mice. RESULTS: Results showed that after S. sarmentosum extract was administered, the expression level of miR-124 increased in liver tissues. However, the protein expression levels of Hedgehog, Ptch, Smo, Gli, P13k, p-Akt, HMGB1, TLR4, p-IκB-α, and NF-κB65 and the mRNA expression levels of Hedgehog, Ptch, Smo, and Gli decreased. The MPO level in the liver, the IL-6, TNF-α, CRP, IL-12, and MMP-9 levels in the plasma, and the serum ALT and AST levels also decreased, thereby reducing LPS/D-GalN-induced liver injury and improving the survival rate of liver-damaged animals within 24 h. CONCLUSIONS: S. sarmentosum extract can alleviate LPS/D-GalN-induced acute liver injury in mice and improve the survival rate of mice. The mechanism may be related to the increase in miR-124 expression, decrease in Hedgehog and HMGB1 signaling pathway activities, and reduction in inflammatory responses in the liver. Hedgehog is a regulatory target for miR-124.

5.
Neuroimage ; 210: 116588, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32004718

RESUMO

An enriched environment (EE) provides multi-dimensional stimuli to the brain. EE exposure for days to months induces functional and structural neuroplasticity. In this study, manganese-enhanced magnetic resonance imaging (MEMRI) was used to map the accumulative whole-brain activities associated with a 7-day EE exposure in freely-moving adult male mice, followed by c-Fos immunochemical assessments. Relative to the mice residing in a standard environment (SE), the mice subjected to EE treatment had significantly enhanced regional MEMRI signal intensities in the prefrontal cortex, somatosensory cortices, basal ganglia, amygdala, motor thalamus, lateral hypothalamus, ventral hippocampus and midbrain dopaminergic areas at the end of the 7-day exposure, likely attributing to enhanced Mn2+ uptake/transport associated with brain activities at both the regional and macroscale network levels. Some of, but not all, the brain regions in the EE-treated mice showing enhanced MEMRI signal intensity had accompanying increases in c-Fos expression. The EE-treated mice were also found to have significantly increased overall amount of food consumption, decreased body weight gain and upregulated tyrosine hydroxylase (TH) expression in the midbrain dopaminergic areas. Taken together, these results demonstrated that the 7-day EE exposure was associated with elevated cumulative activities in the nigrostriatal, mesolimbic and corticostriatal circuits underpinning reward, motivation, cognition, motor control and appetite regulation. Such accumulative activities might have served as the substrate of EE-related neuroplasticity and the beneficial effects of EE treatment on neurological/psychiatric conditions including drug addiction, Parkinson's disease and eating disorder.

6.
Molecules ; 25(3)2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-32012651

RESUMO

Chitin biomass, a rich renewable resource, is the second most abundant natural polysaccharide after cellulose. Conversion of chitin biomass to high value-added chemicals can play a significant role in alleviating the global energy crisis and environmental pollution. In this review, the recent achievements in converting chitin biomass to high-value chemicals, such as 5-hydroxymethylfurfural (HMF), under different conditions using chitin, chitosan, glucosamine, and N-acetylglucosamine as raw materials are summarized. Related research on pretreatment technology of chitin biomass is also discussed. New approaches for transformation of chitin biomass to HMF are also proposed. This review promotes the development of industrial technologies for degradation of chitin biomass and preparation of HMF. It also provides insight into a sustainable future in terms of renewable resources.

7.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 37(1): 129-135, 2020 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-32096386

RESUMO

In order to stimulate the patients' active participation in the process of robot-assisted rehabilitation training of stroke patients, the rehabilitation robots should provide assistant torque to patients according to their rehabilitation needs. This paper proposed an assist-as-needed control strategy for wrist rehabilitation robots. Firstly, the ability evaluation rules were formulated and the patient's ability was evaluated according to the rules. Then the controller was designed. Based on the evaluation results, the controller can calculate the assistant torque needed by the patient to complete the rehabilitation training task and send commands to motor. Finally, the motor is controlled to output the commanded value, which assists the patient to complete the rehabilitation training task. The control strategy was implemented to the wrist function rehabilitation robot, which could achieve the training effect of assist-as-needed and could avoid the surge of assistance torque. In addition, therapists can adjust multiple parameters in the ability evaluation rules online to customize the difficulty of tasks for patients with different rehabilitation status. The method proposed in this paper does not rely on the information from force sensor, which reduces development costs and is easy to implement.


Assuntos
Robótica , Reabilitação do Acidente Vascular Cerebral/instrumentação , Punho/fisiologia , Humanos , Modalidades de Fisioterapia
8.
Artigo em Inglês | MEDLINE | ID: mdl-32058682

RESUMO

Paper-based electrodes are of special interest for the industry due to their degradability, low cost, ion accessibility, and flexibility. However, the poor dispersibility and stability of loading conductive fillers, for example, carbon nanotubes (CNTs), limit their applications. In this study, bacterial cellulose (BC) was embedded within the cellulosic fiber matrix to prepare a paper substrate with a dual fiber matrix structure. BC with its unique nanoporous surface structure assisted the adsorbing, dispersing, and stabilizing of CNTs; cellulosic fibers reduced the cost, enhanced the ion accessibility, and improved the rigidity of the material. The prepared paper electrodes exhibited a high conductivity up to 5.9 × 10-1 S/cm and an extraordinary durability under high bending strain; it can be rolled into a 2 mm radius 800 times while maintaining the conductivity almost constant. The paper electrode had a gravimetric capacitance up to 77.5 F/g, which remained more than 98% after 15,000 charge/discharge cycles. This study suggests that this paper electrode has potential applications in supercapacitors with high performance and durability.

9.
J Craniofac Surg ; 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32028370

RESUMO

BACKGROUND: Nowadays, a sharp, well-defined supratarsal fold and appropriate fullness of the upper eyelid tissue are considered important features of beautiful and youthful eyes. Individuals with thin upper eyelid tissue are at high risk of developing multiple upper eyelid folds and/or sunken appearance after upper blepharoplasty. Innovatively, the authors propose the application of free orbital fat grafting to the postorbicularis oculi space during upper blepharoplasty in order to achieve better aesthetic results. METHODS: Fifty Chinese patients with congenital single eyelids combined with mildly sunken upper eyelid tissue were operated on between June 2017 and October 2018. During blepharoplasty, the lateral portion of the orbital septum was dissected, and appropriate lateral orbital fat was harvested. When the double-eyelid fold was formed and skin was interruptedly sutured, the harvested fat was divided into several pieces each side according to the sunken depth, and they were used to replace a layer on two-thirds of the central region of the supraseptal skin-muscle flap through the zipping gaps. RESULTS: Forty-five patients underwent the follow-up interview for 6 to 18 months with a mean period of 10 months. The satisfaction rate was 82%. No significant asymmetry, irregularities, and sunken upper eyelid and multiple upper eyelid folds occurred. CONCLUSION: The lateral orbital fat grafting to the central region of the supraseptal skin-muscle flap during upper blepharoplasty is an effective and simple method to correct or prevent multiple upper eyelid folds and/or sunken upper eyelid in Asians.

10.
Plant Sci ; 293: 110420, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32081268

RESUMO

Annexin, a multi-gene family in plants, is essential for plant growth and stress responses. Recent studies demonstrated a positive effect of annexin in abiotic stress responses. Interestingly, we found OsANN10, a putative annexin gene in rice, negatively regulated plant responses to osmotic stress. Knocking down OsANN10 significantly decreased the content of H2O2 by increasing Peroxidase (POD) and Catalase (CAT) activities, further reducing oxidative damage in rice leaves, suggesting a negative regulation of OsANN10 in protecting cell membrane against oxidative damage via scavenging ROS under osmotic stress.

11.
Ying Yong Sheng Tai Xue Bao ; 31(1): 17-24, 2020 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-31957376

RESUMO

We investigated the concentrations of carbon (C), nitrogen (N), and phosphorus (P) and C:N:P stoichiometry in soil and litter of Pinus massoniana forest under four different management patterns: inefficient forest transformation, mixture of arbor with shrub and herb, shallow ditch grass planting, and being banned in serious erosion and degradation of red soil in southern China. Our findings could provide scientific basis for soil erosion control and vegetation restoration in this area. The results showed that there were significant differences in soil organic carbon (SOC), TN, TP and litter nutrient content among different management patterns. The nutrient contents in soil and litter under all the four management patterns were significantly higher than that of control, with mixture of arbor with shrub and herb having the highest concentrations. The concentrations of SOC, TN and TP decreased with the increases of soil layer. However, the shallow ditch grass planting mana-gement pattern presented as follows: the concentrations of SOC, TN and TP decreased first and then increased with the increases of soil layer, with the lowest value in 5-20 cm soil layer. There were significant differences in soil C:N, C:P, N:P and litter C:P among different management patterns, and the soil spatial variation was C:N>C:P>N:P. Excepted for mixture of arbor with shrub and herb, C:N was still at a lower level in the other management patterns, and soil C:P and N:P showed higher values overall. Litter C:N, C:P and N:P had opposite change pattern, with inefficient forest transformation and mixture of arbor with shrub and herb being much smaller than the control. Soil C:N and C:P were mainly controlled by SOC content and litter C content, and soil N:P was mainly controlled by soil TP content and litter P content. Soil stoichiometry was affected by soil water content, soil bulk density, pH, and other factors. The relationship between litter and soil nutrients was closely related and showed similar changes.


Assuntos
Pinus , Solo , Carbono , China , Florestas , Nitrogênio
12.
Biochim Biophys Acta Mol Cell Res ; 1867(5): 118659, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31978503

RESUMO

Glycogen synthase kinase-3ß (GSK-3ß) is an evolutionarily conserved serine/threonine kinase, functioning in numerous cellular processes including cell proliferation, DNA repair, cell cycle, signaling and metabolic pathways. GSK-3ß is implicated in different diseases including inflammation, neurodegenerative disease, diabetes and cancers. GSK-3ß is involved in biological processes of tumorigenesis, therefore, it is rational that GSK-3ß inhibitors were employed to target malignant tumors. The effects of GSK-3ß inhibitors in combination of radiation and chemotherapeutic drugs have been reported in various types of cancers, suggesting GSK-3ß would play important roles in cancer treatments. GSK-3ß is involved in multiple signal pathway including Wnt/ß-catenin, PI3K/PTEN/AKT and Notch. GSK-3ß also functions in DNA repair through phosphorylation of DNA repair factors and affecting their binding to chromatin. This review focuses on the molecular mechanism of GSK-3ß in DNA repair, special in base excision repair and double-strands break repair, the roles of GSK-3ß in inhibition of apoptosis through activation of NF-κB, and the effects of GSK-3ß inhibitors on radio- and chemosensitization of various types of cancers. This article is part of a Special Issue entitled: GSK-3 and related kinases in cancer, neurological and other disorders edited by James McCubrey, Agnieszka Gizak and Dariusz Rakus.

13.
Food Chem ; 314: 126098, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31954940

RESUMO

A metabolomics strategy was developed to differentiate strong aroma-type baijiu (SAB) (distilled liquor) from the Sichuan basin (SCB) and Yangtze-Huaihe River Basin (YHRB) through liquid-liquid extraction coupled with GC×GC-TOFMS. PCA effectively separated the samples from these two regions. The PLS-DA training model was excellent, with explained variation and predictive capability values of 0.988 and 0.982, respectively. As a result, the model demonstrated its ability to perfectly differentiate all the unknown SAB samples. Twenty-nine potential markers were located by variable importance in projection values, and twenty-four of them were identified and quantitated. Discrimination ability is closely correlated to the characteristic flavor compounds, such as acid, esters, furans, alcohols, sulfides and pyrazine. Most of the marker compounds were less abundant in the SCB samples than in the YHRB samples. The quantitated markers were further processed using hierarchical cluster analysis for targeted analysis, indicating that the markers had great discrimination power to differentiate the SAB samples.

14.
Postgrad Med J ; 96(1133): 128-133, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31611267

RESUMO

BACKGROUND: Although hyperlipidaemia was a well-known risk factor for ischaemic stroke, the association between triglyceride and first ischaemic stroke remains uncertain. OBJECTIVES: The present study attempted to explore the relationship between triglyceride and first ischaemic stroke in a Chinese community elderly patients with hypertension. METHODS AND RESULTS: This was a retrospective cohort study. We enrolled 3249 consecutive elderly patients with hypertension from a community in China between January 2010 and December 2011. Patients were divided into four groups based on the quartiles of triglyceride. Multivariate Cox regression analysis, subgroup and interaction test were performed to evaluate the relationship between triglyceride and first ischaemic stroke. There were a total of 3249 participants including 1455 male and 1794 female, with a mean age of 71.36±7.18 years. At an average follow-up of 5.5 years, 205 patients were identified to have first ischaemic stroke. After adjustment for potential confounders, using the lowest quartiles of triglyceride as the reference, multivariable HR (95% CI) for first ischaemic stroke increased in parallel with the quartiles of triglyceride (HRs were 1.56 (95% CI 1.07 to 2.51), 1.74 (95% CI 1.07 to 2.84) and 1.85 (95% CI 1.05 to 2.89)) from the second to the fourth quartiles, respectively (p=0.002 for trend). Subgroup and interaction analysis showed that there was no interactive effect on triglyceride and first ischaemic stroke. CONCLUSION: Triglyceride was an independent risk factor for first ischaemic stroke among Chinese elderly patients with hypertension.

15.
Cereb Cortex ; 30(1): 283-295, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31041986

RESUMO

Combat-related mild traumatic brain injury (mTBI) is a leading cause of sustained impairments in military service members and veterans. Recent animal studies show that GABA-ergic parvalbumin-positive interneurons are susceptible to brain injury, with damage causing abnormal increases in spontaneous gamma-band (30-80 Hz) activity. We investigated spontaneous gamma activity in individuals with mTBI using high-resolution resting-state magnetoencephalography source imaging. Participants included 25 symptomatic individuals with chronic combat-related blast mTBI and 35 healthy controls with similar combat experiences. Compared with controls, gamma activity was markedly elevated in mTBI participants throughout frontal, parietal, temporal, and occipital cortices, whereas gamma activity was reduced in ventromedial prefrontal cortex. Across groups, greater gamma activity correlated with poorer performances on tests of executive functioning and visuospatial processing. Many neurocognitive associations, however, were partly driven by the higher incidence of mTBI participants with both higher gamma activity and poorer cognition, suggesting that expansive upregulation of gamma has negative repercussions for cognition particularly in mTBI. This is the first human study to demonstrate abnormal resting-state gamma activity in mTBI. These novel findings suggest the possibility that abnormal gamma activities may be a proxy for GABA-ergic interneuron dysfunction and a promising neuroimaging marker of insidious mild head injuries.

16.
Huan Jing Ke Xue ; 41(1): 438-448, 2020 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854947

RESUMO

We use 3487 surface soil samples, 35 soil profile samples, and 93 agricultural products and root soil samples obtained from the southeastern Tarim basin, Xinjiang, northwestern China (Ruoqiang County and Qiemo County, Bayingguo Mongolia Autonomous Prefecture, and Minfeng County and Yutian County, Hetian Prefecture) to assess As contamination. Multivariate statistical analysis, geostatistics, and global information system (GIS) techniques are used to study:the spatial distribution characteristics of soil As, the effects of various agricultural products on As enrichment, and to compare the characteristics of the As content of agricultural products and root soils in spatially significantly and non-significantly autocorrelated regions. The As content of soil samples were relatively low, and the average As contents determined for agricultural land and non-agricultural land were 9.81 mg·kg-1 and 7.94 mg·kg-1, respectively. We found that 568 surface soil samples (16.3% of all samples) had an As content that exceeded Xinjiang soil background values (11.2 mg·kg-1) and that five samples exceeded the risk screening values (25 mg·kg-1). The Moran's indexes of spatial autocorrelation were>0, and the main aggregation types of spatial autocorrelation of soil As were high-high and low-low types, with the zone of the high-high type being mainly located in the agricultural land of each county. A GIS spatial distribution map showed that the high value area of soil As content presented a flaky or island-like scattered distribution. The standard deviation ellipses showed that the trend direction of soil As content in:Ruoqiang County was from north to south, Qiemo County and Minfeng County were both from southwest to northeast, and Yutian County was from northwest to southeast. The As content of the vertical profiles of the agricultural land in Ruoqiang County fluctuated from the surface to depth, whereas those of other counties were relatively stable. The As enrichment ability of crops was ranked as:root vegetables > walnuts > wheat > corn > red dates. The As contents of corn and red dates showed a significant positive correlation with that of the root soil. There was no significant difference in the As content of agricultural products between significant autocorrelation zones and non-significant autocorrelation zones, whereas there was a significant difference in the As content of root soils.

17.
Vasc Endovascular Surg ; 54(1): 12-16, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31522622

RESUMO

PURPOSE: To investigate the clinical outcomes of endovascular bare stenting in patients with symptomatic isolated superior mesenteric artery (SMA) dissection (ISMAD). METHODS: This study was a retrospective analysis which included a total of 9 patients with symptomatic ISMAD (7 males and 2 females, age range: 48-67 years) who were treated with endovascular bare stenting. Data regarding basic patient clinical characteristics, e-technical success of the operation, and long-term patient outcomes were assessed. RESULTS: Endovascular bare stenting was found to be technically successful in all patients. A total of 9 stents were inserted in these 9 patients. Five patients presented with stable false lumen and 4 patients presented with shrinking of false lumen after stenting. Both the trunk and branches of the SMA remained patent in all patients after stent insertion. There was no incidence of procedure-related complications, with all patients experiencing progressive symptom relief and subsequent symptom abatement within 1 week of the operation. Over a median 24 month follow-up period (range: 12-36 months), abdominal computed tomographic angiography revealed that all patients had obliterated dissections. In addition, there were no instances of stent obstruction, intestinal necrosis, or antiplatelet related bleeding during the follow-up period. CONCLUSIONS: Endovascular bare stenting was found to be a safe and effective treatment for patients with ISMAD.


Assuntos
Aneurisma Dissecante/cirurgia , Procedimentos Endovasculares/instrumentação , Artéria Mesentérica Superior/cirurgia , Stents Metálicos Autoexpansíveis , Idoso , Aneurisma Dissecante/diagnóstico por imagem , Aneurisma Dissecante/fisiopatologia , Procedimentos Endovasculares/efeitos adversos , Feminino , Humanos , Masculino , Artéria Mesentérica Superior/diagnóstico por imagem , Artéria Mesentérica Superior/fisiopatologia , Pessoa de Meia-Idade , Desenho de Prótese , Estudos Retrospectivos , Resultado do Tratamento
18.
Environ Int ; 134: 105283, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31743806

RESUMO

In the last decade, North China (NC) has been one of the most populated and polluted regions in the world. The regional air pollution has had a serious impact on people's health; thus, all levels of government have implemented various pollution prevention measures since 2013. Based on multi-city in situ environmental and meteorological data, as well as the meteorological reanalysis dataset from 2013 to 2017, regional pollution characteristics and meteorological formation mechanisms were analyzed to provide a more comprehensive understanding of the evolution of PM2.5 in NC. The domain-averaged PM2.5 was 79 ±â€¯17 µg m-3 from 2013 to 2017, with a decreasing rate of 10 µg m-3 yr-1. Two automatic computer algorithms were established to identify 6 daily regional pollution types (DRPTs) and 48 persistent regional pollution events (PRPEs) over NC during 2014-2017. The average PM2.5 concentration for the Large-Region-Pollution type (including the Large-Moderate-Region-Pollution and Large-Severe-Region-Pollution types) was 113 ±â€¯40 µg m-3, and more than half of Large-Region-Pollution days and PRPEs occurred in winter. The PRPEs in NC mainly developed from the area south of Hebei. The number of Large-Region-Pollution days decreased notably from 2014 to 2017, the annual number of days varying between 194 and 97 days, whereas a slight decline was observed in winter. In addition, the averaged PM2.5 concentrations and the numbers and durations of the PRPEs decreased. Lamb-Jenkinson weather typing was used to reveal the impact of synoptic circulations on PM2.5 across NC. Generally, the contributions of the variations in circulation to the reduction in PM2.5 levels over NC between 2013 and 2017 were 64% and 45% in summer and winter, respectively. The three most highly polluted weather types were types C, S and E, with an average PM2.5 concentration of 137 ±â€¯40 µg m-3 in winter. Furthermore, three typical circulation dynamics were categorized in the peak stage of the PRPEs, namely, the southerly airflow pattern, the northerly airflow pattern and anticyclone pattern; the averaged relative humidity, recirculation index, wind speed and boundary layer height were 63%, 0.33, 2.0 m s-1 and 493 m, respectively. Our results imply that additional emission reduction measures should be implemented under unfavorable meteorological situations to attain ambient air quality standards in the future.

19.
Postgrad Med J ; 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31806734

RESUMO

BACKGROUND: It is uncertain how diastolic blood pressure (DBP) may associate with ischaemic stroke in elder patients with hypertension. We aimed to explore this relationship in a Chinese community. METHODS: A total of 3315 participants aged ≥60 years with essential hypertension were enrolled between January 2010 and December 2011, and being followed up until 31 December 2016. DBP levels were categorised into five groups (<60, 60-70, 70-80, 80-90 and ≥90 mm Hg), using 70-80 mm Hg as referent. We performed Cox regression analysis and subgroup analyses to evaluate the relationship between DBP and the incidence of ischaemic stroke. RESULTS: Among the 3315 participants, 44.49% were men and they were 71.4 years old on average. During a median follow-up period of 5.5 years, there were 206 onset cases of ischaemic stroke. The HRs for the first ischaemic stroke in the fully adjusted model were 1.32 (95% CI 0.73 to 2.40) for DBP <70 mm Hg, 1.50 (95% CI 1.13 to 2.73) for DBP between 80 and 89.9 mm Hg and 2.31 (95% CI 1.14 to 4.68) for DBP ≥90 mm Hg compared with DBP between 70 and 79.9 mm Hg (p=0.020 for trend). Subgroup and interaction analysis showed no significant findings. CONCLUSIONS: DBP had a non-linear association with the risk of ischaemic stroke among Chinese elderly patients with hypertension. DBP between 70 and 80 mm Hg may be an appropriate indicator for a lower stroke risk.

20.
World J Surg Oncol ; 17(1): 199, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31785609

RESUMO

BACKGROUND: Colorectal cancer is the fourth most common cancer globally and neoadjuvant concurrent chemoradiotherapy (nCRT) and surgery are the standard treatments for locally advanced colorectal carcinoma. This study investigated the association between dynamic changes in absolute lymphocyte counts (ALCs) and disease-free survival (DFS) in rectal cancer patients receiving nCRT and identified factors associated with these changes. METHODS: We retrospectively examined 34 patients with locally advanced rectal cancer who received nCRT followed by surgery and adjuvant chemotherapy. The association between ALCs and DFS and that between ALCs and downstaging were analyzed and potential clinical- and treatment-related factors related to dynamic changes in ALCs were subsequently evaluated. The patient eligibility criteria were as follows: pathologically confirmed rectal adenocarcinoma, clinical stages II-III, ≥ 18 years of age, and so on. Pre-RTL was defined as ALCs obtained before the initiation of nCRT and pre-SL was defined as ALCs obtained before surgery. We measured pre-SL to pre-RTL ratio (pre-SLR), DFS, and ALCs. RESULTS: The median ALC declined significantly during nCRT. A lower pre-SLR was associated with poorer DFS with statistical significance in Kaplan-Meier (p = 0.007), univariate regression (hazard ratio [HR] = 6.287, 95% confidence interval [CI] 1.374-28.781, p = 0.018), and multivariable regression (HR = 7.347, 95% CI 1.595-33.850, p = 0.011) analyses. Neither patient characteristics nor treatment-related factors were related to downstaging. The pelvic bone marrow (PBM) volume receiving at least 30 Gy (V30) was significantly associated with pre-SLR in the univariate (HR = 5.760, 95% CI 1.317-25.187, p = 0.020) and multivariable (HR = 5.760, 95% CI 1.317-25.187, p = 0.020) regression analyses. LIMITATIONS: Our study had several limitations. The sample size was small and the study was performed in a selected population, which may limit the generalization of the findings. CONCLUSIONS: Radiotherapy had a profound impact on the change in ALCs. A lower pre-SLR was significantly associated with poorer DFS in rectal cancer patients receiving nCRT. The V30 of PBM was a predictor of pre-SLR.

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