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1.
Int J Environ Health Res ; 34(5): 2397-2406, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37660259

RESUMO

To investigate the association between mtDNA genetic information and the risk of SF, individuals were conducted in the drinking water endemic fluorosis area in northern China, sequenced the whole genome of mtDNA, identified the SNPs and SNVs, analyzed the haplogroups, and diagnosed SF, and then, the effect of mtDNA genetic information on the risk of SF was evaluated. We find that, D5 haplogroup and its specific SNPs reduced the risk, while the D4 haplogroup and its specific SNPs increased the risk of SF. The number of SNVs in coding regions of mitochondrial respiratory chain (MRC) is different between the controls and cases. This suggests that D5 haplogroup may play a protective role in the risk of SF, while the opposite is observed for the D4 haplogroup, this may relate to their specific SNPs. And SNVs that encode the MRC complex may also be associated with the risk of SF.


Assuntos
DNA Mitocondrial , Água Potável , Humanos , DNA Mitocondrial/genética , Povo Asiático , Haplótipos , Polimorfismo de Nucleotídeo Único , China/epidemiologia
2.
Int J Environ Health Res ; 34(2): 687-696, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36617395

RESUMO

To investigate the potential association between LRP5 rs648438 polymorphism and the risk of skeletal fluorosis (SF) was evaluated in a cross-sectional case-control study conducted in Shanxi, China, in 2019. A total of 973 individuals were enrolled in this study, in which cases and controls were 346 and 627, respectively. SF was diagnosed according to the standard WS/192-2008 (China). The LRP5 rs648438 was detected by the multiple PCR and sequencing. LRP5 rs648438 was found to follow a dominant genetic model using a web-based SNP-STATS software. Logistic regression analysis found that the TC/CC genotype of LRP5 rs648438 might be a protective factor for SF. When stratified by gender, this protective effect of TC/CC genotype in rs648438 was pronounced in males. There was an interaction between gender and rs648438 on risk of SF. Our study suggested that TC/CC genotype of rs648438 might be a protective factor for water-drinking-type skeletal fluorosis, especially in male participants.


Assuntos
Doenças Ósseas Metabólicas , Polimorfismo Genético , Humanos , Masculino , Doenças Ósseas Metabólicas/genética , Estudos de Casos e Controles , China/epidemiologia , Estudos Transversais , Genótipo , Polimorfismo de Nucleotídeo Único , Receptores de LDL/genética
3.
Arch Toxicol ; 97(11): 2919-2928, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37658865

RESUMO

Arsenic is a toxic metal-like element. The toxic reaction of the body to arsenic is related to the ability of arsenic methylation metabolism. As the rate-limiting enzyme of arsenic methylation metabolism, the genetic single nucleotide polymorphisms (SNPs) of arsenic (+ 3 oxidation state) methyltransferase (AS3MT) gene are related to capacity of arsenic methylation. In this paper, we investigated the association of five SNPs (rs7085104, rs3740390, 3740393, rs10748835, and rs1046778) in AS3MT with arsenic methylation metabolizing using the data and samples from a cross-sectional case-control study of arsenic and Type 2 diabetes mellitus conducted in Shanxi, China. A total of 340 individuals were included in the study. Urinary total arsenic (tAs, µg/L) was detected by liquid chromatography-atomic fluorescence spectrometry (LC-AFS). According to "safety guidance value of urinary arsenic for population" as specified in WS/T665-2019 (China), participants were divided into the control group (tAs ≤ 32 µg/L, n = 172) and arsenic-exposed group (tAs > 32 µg/L, n = 168). iAs%, MMA%, and DMA% are as the indicator of arsenic methylation capacity. The genotypes of AS3MT SNPs were examined by Multiple PCR combined sequencing. Linear regression analysis showed that AG + GG genotype in rs7085104 was associated with decreased iAs% and increased DMA%. Moreover, AG + AA genotype in rs10748835 and TC + CC genotype in rs1046778 were associated with decreased iAs% and MMA% and increased DMA%. The interaction between rs7085104 and arsenic is associated with iAs% and DMA%. The interaction of rs3740390 and rs10748835 with arsenic is associated with iAs%. Haplotype CTAC (rs3740393-rs3740390-rs10748835-rs1046778) was associated with lower iAs% and higher DMA%, but this association disappeared after adjusting for age, gender, drink, smoking, BMI and tAs. Haplotype GCAC was associated with decreased MMA%. Our study provides additional support for revealing the factors influencing the metabolic capacity of arsenic methylation and might be helpful to identify the population susceptible to arsenic exposure through individualized screening in the future.


Assuntos
Arsênio , Diabetes Mellitus Tipo 2 , Metiltransferases , Humanos , Estudos de Casos e Controles , China , Estudos Transversais , Metilação , Metiltransferases/genética , Polimorfismo de Nucleotídeo Único
4.
Int J Environ Health Res ; 33(3): 284-298, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34974760

RESUMO

Arsenic is an identified carcinogen for humans.In this study, chronic exposure of human hepatocyte L-02 to low-doses of inorganic arsenic caused cell malignant proliferation. Meanwhile, compared with normal L-02 cells, arsenic-transformed malignant cells, L-02-As displayed more ROS and significantly higher Cyclin D1 expression as well as aerobic glycolysis. Moreover, Akt activation is followed by the upregulation of Cyclin D1 and HK2 expression in L-02-As cells, since inhibition of Akt activity by Ly294002 attenuated the colony formation in soft agar and decreased the levels of Cyclin D1 and HK2. In addition, scavenging of ROS by NAC resulted in a decreased expression of phospho-Akt, HK2 and Cyclin D1, and attenuates the ability of anchorage-independent growth ofL-02-As cells, suggested that ROS mediated the Akt activation in L-02-As cells. In summary, our results demonstrated that ROS contributes to the malignant phenotype of arsenic-transformed human hepatocyte L-02-As via the activation of Akt pathway.


Assuntos
Arsênio , Ciclina D1 , Humanos , Ciclina D1/metabolismo , Arsênio/toxicidade , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proliferação de Células
5.
Pharmacol Res ; 185: 106503, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36241000

RESUMO

Acute myeloid leukemia (AML) is featured with poor prognosis and high mortality, because chemo-resistance, nonspecific distribution and dose-limiting toxicity lead to a high rate of relapse and a very low 5-year survival percentage of less than 25%. CXCR4 is a highly expressed chemokine receptor in multiple types of AML cells and closely associated with the drug resistance and relapse. In this work, we integrate a chemically synthesized CXCR4 antagonistic peptide and doxorubicin using DSPE-mPEG2000 micelles (referred to as M-E5-Dox) that is applied to a very challenging refractory AML mouse model as well as human AML cell lines. Results showed that M-E5-Dox can effectively bind to the CXCR4-expressing AML cells, downregulating the signaling proteins mediated by CXCR4/CXCL12 axis and increasing the cellular uptake of Dox. Importantly, M-E5-Dox remarkably decreases the leukemic cells in the peripheral blood and bone marrow, as well as their infiltration in the spleen and liver of the AML mice, which in turn prolongs the survival significantly. Meanwhile, M-E5-Dox did not increase the cardiotoxicity of Dox. In conclusion, M-E5-Dox harnesses the functions of CXCR4 specific binding and CXCR4 antagonism of the peptide and the tumor cell killing capacity of Dox, which displays significant therapeutic effects and promising translational potentials for the treatment of refractory AML.


Assuntos
Leucemia Mieloide Aguda , Humanos , Camundongos , Animais , Leucemia Mieloide Aguda/metabolismo , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Transdução de Sinais , Peptídeos/farmacologia , Recidiva , Receptores CXCR4
6.
Arch Toxicol ; 96(6): 1673-1683, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35420349

RESUMO

Type 2 diabetes mellitus (T2DM) is one of the major public health problems worldwide; both genetic and environmental factors are its risk factors. Arsenic, an environmental pollutant, might be a risk factor for T2DM, but the association of low-to-moderate level arsenic exposure with the risk of T2DM is still inconsistent. Single nucleotide polymorphisms (SNPs) can affect the development of T2DM, but the study on KEAP1 rs11545829 (G>A) SNP is few. In this paper, we explored the effect of KEAP1 rs11545829 (G>A) SNP and low-to-moderate level arsenic exposure on risk of T2DM in a cross-sectional case-control study conducted in Shanxi, China. Total of 938 participants, including 318 T2DM cases and 618 controls, were enrolled. Blood glycosylated haemoglobin (HbA1c) was detected by Automatic Biochemical Analyzer, and participants with HbA1c≧6.5% were diagnosed as T2DM. Urinary total arsenic (tAs, mg/L), as the indicator of arsenic exposure, was detected by liquid chromatography-atomic fluorescence spectrometry (LC-AFS). Genomic DNA was extracted and the genotypes of KEAP1 rs11545829 SNP were examined by multiplex polymerase chain reaction (PCR). The urinary tAs concentration in recruited participants was 0.075 (0.03-0.15) mg/L, and was associated with an increased risk of T2DM (OR = 8.45, 95% CI 2.63-27.17); rs11545829 mutation homozygote AA genotype had a protective effect on risk of T2DM (OR = 0.42, 95 % CI 0.25-0.73). Although this protective effect of AA genotype was found in participants with higher urinary tAs level (>0.032 mg/L) (OR = 0.48, 95% CI 0.26-0.86), there was no interaction effect for arsenic exposure and rs11545829 SNP on risk of T2DM. In addition, BMI modified the association between rs11545829 SNP and the risk of T2DM (RERI = -1.11, 95% CI -2.18-0.04). The present study suggest that low-to-moderate level arsenic exposure may be a risk factor, while KEAP1 rs11545829 SNP mutation homozygote AA genotype may be a protective factor for risk of T2DM, especially for T2DM patients with urinary tAs level>0.032 mg/L.


Assuntos
Arsênio , Diabetes Mellitus Tipo 2 , Proteína 1 Associada a ECH Semelhante a Kelch , Arsênio/toxicidade , Arsênio/urina , Estudos de Casos e Controles , China/epidemiologia , Estudos Transversais , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/genética , Predisposição Genética para Doença , Genótipo , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Polimorfismo de Nucleotídeo Único
7.
Int J Environ Health Res ; : 1-16, 2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36264688

RESUMO

Arsenic has been identified as a carcinogen, although the molecular mechanism underlying itscarcinogenesis has not been fully elucidated. To date, only a few studies have attempted to confirm a direct link between oxidative stress and the Warburg effect . This study demonstrated that 0.2 µmol/L As3+ induced the Warburg effect to contribute to abnormal proliferation of L-02 cells, that was mediated by upregulation of hexokinase 2 (HK2), a key enzyme in glycolysis. Further study indicated that arsenic-induced accumulation of reactive oxygen species (ROS) activated the nuclear factor kappa B (NF-κB) signaling pathway by phosphorylation of p65 at the Ser536 and Ser276 sites, leading to upregulated expression of HK2. We therefore concluded that the ROS/NF-κB/HK2 axis contributes to the Warburg effect and cell proliferation induced by low doses of arsenic.AbbreviationsROS, Reactive oxygen species; NAC, N-acetyl-L-cysteine; 2-DG, 2-deoxy-D-glucose; 2-NBDG, 2-Deoxy-2-[(7-nitro-2,1,3-benzoxadiazol-4-yl)amino]-D-glucose.

8.
Ecotoxicol Environ Saf ; 225: 112735, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34478979

RESUMO

BACKGROUND: The kidney toxicity of fluoride exposure has been demonstrated in animal studies, and a few studies have reported kidney function injury in children with fluoride exposure. However, epidemiological information for the effects of long-term fluoride exposure on adult kidney function remains limited. METHODS: We conducted a cross-sectional investigation in Wenshui County, Shanxi Province to examine the association between fluoride exposure and kidney function in adults, and a total of 1070 adults were included in our study. Urinary fluoride concentrations were measured using the national standardized ion selective electrode method. And markers of kidney function injury (urinary NAG, serum RBP, serum Urea, serum C3, serum UA and serum αl-MG) were measured using automatic biochemical analyzer. Multivariate linear regression analysis and binary logistic regression model were used to assess the relationship between urinary fluoride and markers of kidney function injury. RESULTS: Urinary fluoride was positively correlated with urinary NAG and serum Urea, negatively correlated with serum C3. In multivariate linear regression models, every 1 mg/L increment of urinary fluoride was associated with 1.583 U/L increase in urinary NAG, 0.199 mmol/L increase in serum Urea, 0.037 g/L decrease in serum C3 after adjusting for potential confounding factors. In the binary logistic regression model, higher levels of urinary fluoride were associated with an increased risk of kidney function injury. Determination of kidney function based on urinary NAG, every 1 mg/L increment in the urinary fluoride concentrations was associated with significant increases of 22.8% in the risk of kidney function injury after adjusting for potential confounding factors. Sensitivity analysis for the association between urinary fluoride concentrations and markers of kidney function (urinary NAG, serum Urea, and serum C3) by adjusting for the covariates, it is consistent with the primary analysis. CONCLUSIONS: Our study suggests that long-term fluoride exposure is associated with kidney function in adults, and urinary NAG is a sensitive and robust marker of kidney dysfunction caused by fluoride exposure, which could be considered for the identification of early kidney injury in endemic fluorosis areas.


Assuntos
Fluoretos , Rim , Animais , China/epidemiologia , Estudos Transversais , Fluoretos/análise , Fluoretos/toxicidade , Rim/química , Análise Multivariada
9.
Int J Environ Health Res ; 31(4): 421-432, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31565963

RESUMO

To evaluate the association between ALOX15 gene polymorphism and skeletal fluorosis (SF), a case-control study was conducted. A total of 1023 individuals, including 308 Tibetans, 290 Kazaks and 425 Han, were enrolled in this study, in which cases and controls were 278 and 745, respectively. SF was diagnosed by X-ray absorptiometry. SNPs were genotyped using the Sequenom Mass ARRAY system. The genotypes of ALOX15 rs7220870, rs2664593 and rs1107852 were not associated with the risk of SF. After reconstructing the haplotype of rs7220870 and rs11078528, the risk effect of haplotype CA was found in Han participants aged ≤45 years or with moderate fluoride intake. Diplotype of CC/CC had a protective effect on SF risk in Han participants; whereas, CA/CC diplotype showed a risk effect on SF risk in participants aged ≥65; Our results provide the first evidence of an association between ALOX15 gene polymorphism and SF risk in Han participants.Abbreviation: SF: Skeletal fluorosis; SNP: Single Nucleotide polymorphism.


Assuntos
Araquidonato 15-Lipoxigenase/genética , Doenças Ósseas Metabólicas/epidemiologia , Polimorfismo Genético , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Ósseas Metabólicas/genética , Estudos de Casos e Controles , China/epidemiologia , China/etnologia , Estudos Transversais , Feminino , Humanos , Cazaquistão/etnologia , Masculino , Pessoa de Meia-Idade , Tibet/etnologia , Adulto Jovem
10.
J Headache Pain ; 22(1): 107, 2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34503441

RESUMO

BACKGROUND: Medication-overuse headache (MOH) is a relatively frequently occurring secondary headache caused by overuse of analgesics and/or acute migraine medications. It is believed that MOH is associated with dependence behaviors and substance addiction, in which the salience network (SN) and the habenula may play an important role. This study aims to investigate the resting-state (RS) functional connectivity between the habenula and the SN in patients with MOH complicating chronic migraine (CM) compared with those with episodic migraine (EM) and healthy controls (HC). METHODS: RS-fMRI and 3-dimensional T1-weighted images of 17 patients with MOH + CM, 18 patients with EM and 30 matched healthy HC were obtained. The RS-fMRI data were analyzed using the independent component analysis (ICA) method to investigate the group differences of functional connectivity between the habenula and the SN in three groups. Correlation analysis was performed thereafter with all clinical variables by Pearson correlation. RESULTS: Increased functional connectivity between bilateral habenula and SN was detected in patients with MOH + CM compared with patients with EM and HC respectively. Correlation analysis showed significant correlation between medication overuse duration and habenula-SN connectivity in MOH + CM patients. CONCLUSIONS: The current study supported MOH to be lying within a spectrum of dependence and addiction disorder. The enhanced functional connectivity of the habenula with SN may correlate to the development or chronification of MOH. Furthermore, the habenula may be an indicator or treatment target for MOH for its integrative role involved in multiple aspects of MOH.


Assuntos
Habenula , Transtornos da Cefaleia Secundários , Transtornos de Enxaqueca , Cefaleia , Transtornos da Cefaleia Secundários/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Transtornos de Enxaqueca/complicações , Transtornos de Enxaqueca/diagnóstico por imagem
11.
Cephalalgia ; 39(11): 1382-1395, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31053037

RESUMO

BACKGROUND: ATP1A2 has been identified as the genetic cause of familial hemiplegic migraine type 2. Over 80 ATP1A2 mutations have been reported, but no data from Chinese family studies has been included. Here, we report the first familial hemiplegic migraine type 2 Chinese family with a novel missense mutation. METHODS: Clinical manifestations in the family were recorded. Blood samples from patients and the unaffected members were collected for whole-exome sequencing to identify the pathogenic mutation. Seven online softwares (SIFT, PolyPhen-2, PROVEAN, PANTHER, MutationTaster2, MutationAssessor and PMut) were used for predicting the pathogenic potential of the mutation. PredictProtein, Jpred 4 and PyMOL were used to analyze structural changes of the protein. The mutation function was further tested by Methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay. RESULTS: All patients in the family had typical hemiplegic migraine attacks. Co-segregation of the mutation with the migraine phenotype in four generations, with 10 patients, was completed. The identified novel mutation, G762S in ATP1A2, exhibited the disease-causing feature by all the predictive softwares. The mutation impaired the local structure of the protein and decreased cell viability. CONCLUSION: G762S in ATP1A2 is a novel pathogenic mutation identified in a Chinese family with familial hemiplegic migraine, which causes loss of function by changing the protein structure of the Na+/K+-ATPase α2 subunit.


Assuntos
Enxaqueca com Aura/genética , ATPase Trocadora de Sódio-Potássio/genética , Povo Asiático/genética , Feminino , Humanos , Masculino , Mutação de Sentido Incorreto , Linhagem , Adulto Jovem
12.
Eur Neurol ; 82(4-6): 68-74, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31825923

RESUMO

OBJECTIVE: This study aims to further assess the rates and risk factors for relapse in medication overuse headache (MOH) patients in China. METHODS: The patients were admitted to neurology outpatient clinics at Chinese PLA General Hospital (primarily for headache) and diagnosed with MOH. They responded well to 2 months of preventive treatment and completed a 1-year consultation. General information was collected, including demographic characteristics (age, height, weight, and education level), the clinical features of the headache and the use of pain relievers (type, frequency and duration). Differences in each factor between the group with relapse and the group without relapse were analyzed by the chi-square test or Wilcoxon test. Variables with a p < 0.05 were included as independent variables in nonconditional logistic regression analysis. RESULTS: In total, 129 patients were recruited for this retrospective study. The relapse rate of the MOH patients at the 1-year follow-up was 24.8%. The relapse rate was significantly higher in the patients with migraine (29/97, 29.9%) than in the patients with tension-type headache (3/32, 9.4%) and in the patients with low education levels (middle school or lower; 24/77, 31.6%) than in those with high education levels (high school or higher; 8/52, 15.4%). Nonconditional logistic regression analysis showed that the type of primary headache was an independent risk factor for MOH relapse (OR 3.719, p = 0.044). CONCLUSIONS: The relapse rate of MOH patients at the 1-year follow-up was 24.8% in China. The type of primary headache is an independent risk factor for MOH relapse, and patients with migraine as the primary headache are more prone to relapse.


Assuntos
Transtornos da Cefaleia Secundários/tratamento farmacológico , Transtornos da Cefaleia Secundários/epidemiologia , Adulto , Analgésicos/uso terapêutico , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Fatores de Risco
13.
Cephalalgia ; 38(3): 600-603, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28376658

RESUMO

Background Primary cough headache (PCH) is precipitated by coughing or the Valsalva manoeuver (VM), and its underlying pathophysiology remains unclear. Case report We report a case of recurrent cough headaches precipitated by VM with transient increase of intracranial pressure (ICP) diagnosed by measuring left sigmoid sinus pressure. Bilateral internal jugular vein valve incompetence (IJVVI) was also diagnosed by Doppler ultrasonography during a VM. Indomethacin was administered for over four months, and the headache had completely disappeared at the four-month follow-up. Conclusions Cough headache might be associated with a transient increase of ICP induced by IJVVI, which might partially explain the pathophysiology of VM-induced headache. Detecting the internal jugular vein during a VM might be used as diagnostic procedure for patients who have PCH during resting and VM. If it is necessary, monitoring the ICP could be considered.


Assuntos
Transtornos da Cefaleia Primários/etiologia , Hipertensão Intracraniana/complicações , Veias Jugulares/patologia , Válvulas Venosas/patologia , Adulto , Humanos , Veias Jugulares/diagnóstico por imagem , Masculino , Ultrassonografia Doppler em Cores , Manobra de Valsalva , Válvulas Venosas/diagnóstico por imagem
14.
Headache ; 57(10): 1498-1506, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28925506

RESUMO

BACKGROUND: Laughing is a rare precipitating factor for headaches, and the pathogenesis underlying laugh-induced headache (LH) remains unclear. METHODS: Two cases of headache triggered predominantly by laughing were presented in this article. We also reviewed the published English literature regarding LH, summarized the clinical characteristics of LH, and discussed the probable pathophysiological mechanisms. RESULTS: In the first patient, magnetic resonance imaging of the brain revealed cerebellar tonsillar herniation through the foramen magnum. In the second patient, we did not find any evidence of intracranial disease. The literature review showed that LH is a mild to severe, non-pulsating headache. In most cases, the duration of each attack was limited to a few minutes. The headache usually bursts after laughing and reaches its peak almost immediately. In some cases, the headache can only be induced by mirthful laughing rather than by fake laughing. CONCLUSION: LH can be categorized as primary LH and secondary LH. Changes in the spatial structure in the posterior cranial fossa and cerebrospinal fluid circulation may contribute to the development of secondary LH. Primary LH, primary cough headache, and primary exercise headache may share some common pathogenesis. And we speculate that the regions of the brain associated with the expression of mirth might be associated with LH.


Assuntos
Cefaleia/etiologia , Cefaleia/fisiopatologia , Riso , Adulto , Encéfalo/diagnóstico por imagem , Feminino , Cefaleia/diagnóstico por imagem , Humanos , Riso/fisiologia , Masculino , Adulto Jovem
15.
Sci Rep ; 14(1): 9438, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658609

RESUMO

The cutting and crushing of coal and rock containing gangue is the result of the coupling effect of multiple factors. The geometric parameters of the working mechanism, the kinematic parameters of the shearer, and the physical and mechanical properties of the coal and rock to be cut all affect the cutting and crushing process of the shearer. To study the coal falling trajectory of cutting coal and rock using a spiral drum, optimal cutting parameters were obtained, efficient cutting using a spiral drum was achieved, and analysis of the coal falling trajectory and strength of the drum of a shearer based on bidirectional coupling technology was proposed based on particle discrete element contact theory and virtual prototype technology. The discrete element method multi-flexible body dynamics two-way coupling method was used to obtain cutting and interactive information about the spiral drum for a complex coal seam with gangue. The cutting conditions of the spiral drum under different cutting depths, rotational speeds, and traction speeds were determined. The movement status of coal and rock particles was monitored under different working conditions. Coal falling trajectory equations for the coal and rock particles were compiled under different working conditions, and the coal falling trajectory curve was drawn. The optimal coal loading rate was used as the measurement standard for the coal falling trajectory, and the optimal coal falling trajectory of the drum was obtained through full factor experiments. The load of the drum and pick was extracted, their stress and deformation were analyzed, and fatigue life analysis was performed on the pick with the highest stress. The results indicate that the maximum deformation occurs on the cutting teeth that are cutting hard gangue. The stress of the tooth seat is mainly concentrated at the root of the tooth seat, and its maximum equivalent stress is less than the yield limit value of the selected material. Therefore, the material selection and structural design of the drum are safe and reliable. By building a coal mining machine cutting coal and rock experimental platform and monitoring the working status of the designed spiral drum, it meets the usage requirements. Based on industrial experiments conducted underground, the measured average coal loading rate of the shearer drum was 46.31%, achieving stable operation and verifying that the designed drum of the shearer has an efficient cutting ability.

16.
Biol Trace Elem Res ; 202(2): 493-503, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37237135

RESUMO

This study aimed to investigate the potential role of pyruvate kinase M2 (PKM2) and extracellular regulated protein kinase (ERK) in arsenic-induced cell proliferation. L-02 cells were treated with 0.2 and 0.4 µmol/L As3+, glycolysis inhibitor (2-deoxy-D-glucose,2-DG), ERK inhibitor [1,4-diamino-2,3-dicyano-1,4-bis(2-aminophenylthio)-butadiene, U0126] or transfected with PKM2 plasmid. Cell viability, proliferation, lactate acid production, and glucose intake capacity were determined by CCK-8 assay, EdU assay, lactic acid kit and 2-deoxy-2-[(7-nitro-2,1,3-benzoxadiazol-4-yl) amino]-D-glucose (2-NBDG) uptake kit, respectively. Also, levels of PKM2, phospho-PKM2S37, glucose transporter protein 1 (GLUT1), lactate dehydrogenase A (LDHA), ERK, and phospho-ERK were detected using Western blot and the subcellular localization of PKM2 in L-02 cells was detected by immunocytochemistry (ICC). Treatment with 0.2 and 0.4 µmol/L As3+ for 48 h increased the viability and proliferation of L-02 cells, the proportion of 2-NBDG+ cell and lactic acid in the culture medium, and GLUT1, LDHA, PKM2, phospho-PKM2S37, and phospho-ERK levels and PKM2 in nucleus. Compared with the 0.2 µmol/L As3+ treatment group, the lactic acid in the culture medium, cell proliferation and cell viability, and the expression of GLUT1 and LDHA were reduced in the group co-treated with siRNA-PKM2 and arsenic or in the group co-treated with U0126. Moreover, the arsenic-increased phospho-PKM2S37/PKM2 was decreased by U0126. Therefore, ERK/PKM2 plays a key role in the Warburg effect and proliferation of L-02 cells induced by arsenic, and also might be involved in arsenic-induced upregulation of GLUT1 and LDHA. This study provides a theoretical basis for further elucidating the carcinogenic mechanism of arsenic.


Assuntos
Arsênio , Humanos , Arsênio/toxicidade , Arsênio/metabolismo , Proteínas Quinases/metabolismo , Transportador de Glucose Tipo 1 , Proliferação de Células , Hepatócitos/metabolismo , Glucose/farmacologia , Glucose/metabolismo , Ácido Láctico , Linhagem Celular Tumoral
17.
Chem Commun (Camb) ; 60(40): 5318-5321, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38666525

RESUMO

A novel poly(dibenzofuran isatin) (PBFI) with π conjugated structure was synthesized. Through the facile ring-opening reaction, flexible and hydrophilic side chains with hydroxyl and quaternary ammounium groups were grafted into PBFI. Obtained PBFI-x%GTA membranes with twisted polymer structure and multiple hydrogen bonding sites displayed high HT-PEMFC performance.

18.
Toxics ; 12(1)2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38251038

RESUMO

Limited studies have demonstrated that inorganic arsenic exposure is positively associated with serum vitamin D levels, although the correlation between urinary arsenic species and serum vitamin D has not been investigated in areas of water-borne arsenicosis. A cross-sectional study of 762 participants was conducted in Wenshui Country, Shanxi Province, a water-borne arsenicosis area. The results showed a positive relationship between urinary arsenic species (inorganic arsenic (iAs), methylarsonic acid (MMAV), dimethylarsinic acid (DMAV) and serum 25(OH)D. Log-binomial regression analysis indicated a 0.4% increase in the risk of vitamin D excess for every 1-unit increment in the Box-Cox transformed urinary DMAV after adjustment for covariates. After stratifying populations by inorganic arsenic methylation metabolic capacity, serum 25(OH)D levels in the populations with iAs% above the median and primary methylation index (PMI) below the median increased by 0.064 ng/mL (95% CI: 0.032 to 0.096) for every one-unit increase in the Box-Cox transformed total arsenic (tAs) levels. Serum 25(OH)D levels increased by 0.592 ng/mL (95% CI: 0.041 to 1.143) for every one-unit rise in the Box-Cox transformed iAs levels in people with skin hyperkeratosis. Overall, our findings support a positive relationship between urinary arsenic species and serum 25(OH)D. It was recommended that those residing in regions with water-borne arsenicosis should take moderate vitamin D supplements to avoid vitamin D poisoning.

19.
Front Chem ; 11: 1115495, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36762192

RESUMO

Tumor cells and corrupt stromal cells in the tumor microenvironment usually overexpress cancer-specific markers that are absent or barely detectable in normal cells, providing available targets for inhibiting the occurrence and development of cancers. It is noticeable that therapeutic peptides are emerging in cancer therapies and playing more and more important roles. Moreover, the peptides can be self-assembled and/or incorporated with polymeric molecules to form nanoparticles via non-covalent bond, which have presented appealing as well as enhanced capacities of recognizing targeted cells, responding to microenvironments, mediating internalization, and achieving therapeutic effects. In this review, we will introduce the peptide-based nanoparticles and their application advances in targeting tumor cells and stromal cells, including suppressive immune cells, fibrosis-related cells, and angiogenic vascular cells, for cancer therapy.

20.
Sci Rep ; 13(1): 3489, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36859439

RESUMO

The recognition of cutting state of coal-rock is the key technology to realize "unmanned" mining in coal face. In order to realized real-time perception and accurate judgment of coal-rock cutting state information, this paper combined the field test sampling, construction technology of complex coal seam, virtual prototype technology, bidirectional coupling technology, data processing theory, image fusion method, and deep learning theory to carry out multi domain deep fusion experimental research on multi-source heterogeneous data of coal and rock cutting state. The typical complex coal seam containing gangue, inclusion, and minor fault in Yangcun mine of Yanzhou mining area was taken as the engineering object. The high-precision three-dimensional simulation model of the complex coal seam that can update and replace particles was constructed. Based on the simulation results of Discrete Element Method-Multi Flexible Body Dynamics (DEM-MFBD), the one-dimensional original vibration acceleration signals of the key components of the shearer cutting part were determined, including spiral drum, rocker arm shell, and square head. After transforming one-dimensional original signal data into two-dimensional time-frequency images by Short-time Fourier Transform, morphological wavelet image fusion technology was used to realize the effective fusion of characteristic information of spiral drum, rocker arm shell, and square head under different working conditions. Based on the deep learning theory, the DCGAN-RFCNN (Deep Convolutional Generative Adversarial Networks-Random Forest Convolutional Neural Networks) coal and rock cutting state recognition network model was constructed. Combining convolution neural network with random forest recognition classifier, RFCNN coal and rock cutting state recognition classification model was constructed, and the recognition network model was trained to obtain the model recognition results. Through the comparative experimental analysis of the RFCNN network model with different recognition network models and different synthetic sample numbers in the recognition network, the effectiveness of the recognition network model was verified. The results show that: When synthetic samples are not included in each working condition in the RFCNN model, the average recognition rate is 90.641%. With the increase of the number of synthetic samples, the recognition rate of coal and rock cutting state increases. When the number of synthetic samples added to each working condition reaches 5000, the recognition effect is the best, and the average recognition rate reaches 98.344%, which verifies the superiority of enriching the data set by using the improved DCGAN network. Also, the RFCNN outperformed the other variants: it obtained higher recognition accuracy by 25.085, 21.925 and 19.337%, respectively, over SVW, CNN, and AlexNet. Also, the experimental platform of shearer cutting coal and rock was built, where the coal and rock cutting state recognition network was trained and tested based on the migration learning theory. Through the statistical test results, the accuracy of coal and rock cutting state recognition is 98.64%, which realizes the accurate recognition of coal and rock cutting state.

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