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1.
Phys Chem Chem Phys ; 25(35): 23954-23962, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37642559

RESUMO

A broken-gap heterojunction is a bright approach for designing tunneling field-effect transistors (TFETs) due to its distinct quantum tunneling mechanisms. In this study, we investigate the electronic structure and transport characteristics of a SiC/Ti2CO2 heterojunction, as well as the impacts of electric field and strain on the electronic properties via density functional theory. We determine that the interfacial atoms of the heterojunction are covalently bonded, forming a type-III heterojunction with a broken-gap. There exists band-to-band tunneling (BTBT) from the valence band (VB) of SiC to the conduction band (CB) of Ti2CO2. The creation of the heterojunction also enhances the carrier mobility arising from the large elastic modulus and the decrease of deformation potential. The current-voltage (I-V) characteristics of the device demonstrate a pronounced negative differential resistance (NDR) effect, along with a current that is about ten times greater than that of the vdW type-III heterojunction. Moreover, the tunneling window of SiC/Ti2CO2 is only slightly altered when subjected to an external electric field and vertical strain, demonstrating the remarkable stability of its type-III band alignments. Our results indicate that the SiC/Ti2CO2 heterojunction is useful to construct high-performance TFETs, and also introduces new ideas to design TFETs by using type-III covalent-bond heterojunctions.

2.
Arch Toxicol ; 89(1): 33-45, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24838295

RESUMO

How to maintain the genetic integrity of cultured human embryonic stem (hES) cells is raising crucial concerns for future clinical use in regenerative medicine. Mitomycin C(MMC), a DNA damage agent, is widely used for preparation of feeder cells in many laboratories. However, to what extent MMC affects the karyotypic stability of hES cells is not clear. Here, we measured residual MMC using High Performance Liquid Chromatography-Mass Spectrometry/Mass Spectrometry following each step of feeder preparation and found that 2.26 ± 0.77 and 3.50 ± 0.92 ng/ml remained in mouse feeder cells and human feeder cells, respectively. In addition, different amounts of MMC caused different chromosomal aberrations in hES cells. In particular, one abnormality, dup(1)(p32p36), was the same identical to one we previously reported in another hES cell line. Using Affymetrix SNP 6.0 arrays, the copy number variation changes of the hES cells maintained on MMC-inactivated feeders (MMC-feeder) were significantly more than those cultured on γ-inactivated feeder (IR-feeder) cells. Furthermore, DNA damage response (DDR) genes were down-regulated during long-term culture in the MMC-containing system, leading to DDR defect and shortened telomeres of hES cells, a sign of genomic instability. Therefore, MMC-feeder and MMC-induced genomic variation present an important safety problem that would limit such hES from being applied for future clinic use and drug screening.


Assuntos
Técnicas de Cultura de Células/métodos , Dano ao DNA , Células-Tronco Embrionárias/efeitos dos fármacos , Instabilidade Genômica , Mitomicina/toxicidade , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Células-Tronco Embrionárias/patologia , Humanos , Cariotipagem , Mitomicina/análise , Reação em Cadeia da Polimerase , Espectrometria de Massas em Tandem
3.
World J Diabetes ; 15(2): 170-185, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38464370

RESUMO

BACKGROUND: Helicobacter pylori (H. pylori) infection is related to various extragastric diseases including type 2 diabetes mellitus (T2DM). However, the possible mechanisms connecting H. pylori infection and T2DM remain unknown. AIM: To explore potential molecular connections between H. pylori infection and T2DM. METHODS: We extracted gene expression arrays from three online datasets (GSE60427, GSE27411 and GSE115601). Differentially expressed genes (DEGs) commonly present in patients with H. pylori infection and T2DM were identified. Hub genes were validated using human gastric biopsy samples. Correlations between hub genes and immune cell infiltration, miRNAs, and transcription factors (TFs) were further analyzed. RESULTS: A total of 67 DEGs were commonly presented in patients with H. pylori infection and T2DM. Five significantly upregulated hub genes, including TLR4, ITGAM, C5AR1, FCER1G, and FCGR2A, were finally identified, all of which are closely related to immune cell infiltration. The gene-miRNA analysis detected 13 miRNAs with at least two gene cross-links. TF-gene interaction networks showed that TLR4 was coregulated by 26 TFs, the largest number of TFs among the 5 hub genes. CONCLUSION: We identified five hub genes that may have molecular connections between H. pylori infection and T2DM. This study provides new insights into the pathogenesis of H. pylori-induced onset of T2DM.

4.
Nutr Rev ; 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38472140

RESUMO

With increasing attention to diabetes remission, various special dietary patterns have been found to be effective in achieving diabetes remission. The effect of a single dietary pattern on lowering blood glucose is clear, but studies on the synergistic effects of different dietary patterns are limited. This article describes the types of intermittent fasting and ketogenic diets, potential mechanisms, contraindications of combination diets, recommendations for combination diets, and their health outcomes. This paper aims to illustrate the evidence for intermittent fasting combined with a ketogenic diet on outcomes of diabetes remission and effect on blood glucose control. Knowledge of these findings can help doctors and patients determine dietary patterns for achieving diabetes remission and understanding their application.

5.
Fungal Genet Biol ; 56: 33-41, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23591122

RESUMO

Melanized appressoria are highly specialized infection structures formed by germ tubes of the rice blast fungus Magnaporthe oryzae for plant infection. M. oryzae also forms appressorium-like structures on hyphal tips. Whereas appressorium formation by conidial germ tubes has been well characterized, formation of appressorium-like structures by hyphal tips is under-investigated. In a previous study, we found that the chs7 deletion mutant failed to form appressoria on germ tubes but were normal in the development of appressorium-like structures on artificial hydrophobic surfaces. In this study, we compared the differences between the formation of appressoria by germ tubes and appressorium-like structures by hyphal tips in M. oryzae. Structurally, both appressoria and appressorium-like structures had a melanin layer that was absent in the pore region. In general, the latters were 1.4-fold larger in size but had lower turgor pressure than appressoria, which is consistent with its lower efficiency in plant penetration. Treatments with cAMP, IBMX, or a cutin monomer efficiently induced appressorium formation but not the development of appressorium-like structures. In contrast, coating surfaces with waxes stimulated the formation of both infection structures. Studies with various signaling mutants indicate that Osm1 and Mps1 are dispensable but Pmk1 is essential for both appressorium formation and development of appressorium-like structures on hyphal tips. Interestingly, the cpkA mutant was reduced in the differentiation of appressorium-like structures but not appressorium formation. We also observed that the con7 mutant generated in our lab failed to form appressorium-like structures on hyphal tips but still produced appressoria by germ tubes on hydrophobic surfaces. Con7 is a transcription factor regulating the expression of CHS7. Overall, these results indicate that the development of appressorium-like structures by hyphal tips and formation of appressoria by germ tubes are not identical differentiation processes in M. oryzae and may involve different molecular mechanisms.


Assuntos
Hifas/citologia , Magnaporthe/citologia , Regulação Fúngica da Expressão Gênica , Genes Fúngicos , Hifas/química , Magnaporthe/química , Melaninas/análise , Microscopia , Mutação , Oryza/microbiologia , Doenças das Plantas/microbiologia , Transdução de Sinais
6.
BMC Med Genomics ; 16(1): 167, 2023 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-37454083

RESUMO

OBJECTIVES: Epidemiological studies have confirmed that low birth weight (BW) is related to neuroticism and they may have a common genetic mechanism based on phenotypic correlation research. We conducted our study on a European population with 159,208 neuroticism and 289,142 birth weight samples. In this study, we aimed to identify new neuroticism single nucleotide polymorphisms (SNPs) and pleiotropic SNPs associated with neuroticism and BW and to provide more theoretical basis for the pathogenesis of the disease. METHODS: We estimated the pleiotropic enrichment between neuroticism and BW in two independent Genome-wide association studies (GWAS) when the statistical thresholds were Conditional False Discovery Rate (cFDR) < 0.01 and Conjunctional Conditional False Discovery Rate (ccFDR) < 0.05. We performed gene annotation and gene functional analysis on the selected significant SNPs to determine the biological role of gene function and pathogenesis. Two-sample Mendelian Randomization (TSMR) analysis was performed to explore the causal relationship between the neuroticism and BW. RESULTS: The conditional quantile-quantile plots (Q-Q plot) indicated that neuroticism and BW have strong genetic pleiotropy enrichment trends. With the threshold of cFDR < 0.001, we identified 126 SNPs related to neuroticism and 172 SNPs related to BW. With the threshold of ccFDR < 0.05, we identified 62 SNPs related to both neuroticism and BW. Among these SNPs, rs8039305 and rs35755513 have eQTL (expressed quantitative trait loci) and meQTL (methylation quantitative trait loci) effects simultaneously. Through GO enrichment analysis we also found that the two pathways of positive regulation of "mesenchymal cell proliferation" and "DNA-binding transcription factor activity" were significantly enriched in neuroticism and BW. Mendelian randomization analysis results indicate that there is no obvious causal relationship between neuroticism and birth weight. CONCLUSION: We found 126 SNPs related to neuroticism, 172 SNPs related to BW and 62 SNPs associated with both neuroticism and BW, which provided a theoretical basis for their genetic mechanism and novel potential targets for treatment/intervention development.


Assuntos
Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único , Humanos , Estudo de Associação Genômica Ampla/métodos , Neuroticismo , Peso ao Nascer/genética , Predisposição Genética para Doença
7.
Front Endocrinol (Lausanne) ; 14: 1237832, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37645409

RESUMO

Aims: This study aims to describe the clinical characteristics, laboratory data and complications of hospitalized COVID-19 patients with type 2 diabetes mellitus (T2DM) since epidemic prevention and control optimization was adjusted in December 2022 in China. Methods: This retrospective multicenter study included 298 patients with confirmed type 2 diabetes mellitus with or without COVID-19. We collected data from the first wave of the pandemic in The Fifth Affiliated Hospital of Guangzhou Medical University, Loudi Central Hospital and The First People's Hospital of Xiangtan from December 1, 2022 to February 1, 2023. We extracted baseline data, clinical symptoms, acute complications, laboratory findings, treatment and outcome data of each patient from electronic medical records. Results: For among 298 hospitalized patients with type 2 diabetes, 136 (45.6%) were COVID-19 uninfected, and 162 (54.4%) were COVID-19 infected. We found that the incidence of cough, fatigue, fever, muscle soreness, sore throat, shortness of breath, hyposmia, hypogeusia and polyphagia (all p<0.01) were significantly higher in the exposure group. They showed higher levels of ketone (p=0.04), creatinine (p<0.01), blood potassium (p=0.01) and more diabetic ketoacidosis (p<0.01). Patients with COVID-19 less use of metformin (p<0.01), thiazolidinediones (p<0.01) and SGLT2 (p<0.01) compared with patients without COVID-19. Conclusion: COVID-19 patients with diabetes showed more severe respiratory and constitutional symptoms and an increased proportion of hyposmia and hypogeusia. Moreover, COVID-19 patients with diabetes have a higher incidence of acute complications, are more prone to worsening renal function, and are more cautious about the use of antidiabetic drugs.


Assuntos
Ageusia , COVID-19 , Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Estudos Retrospectivos , Anosmia , COVID-19/complicações , COVID-19/epidemiologia , China/epidemiologia
8.
J Dig Dis ; 23(4): 209-219, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35373467

RESUMO

OBJECTIVE: In this study we aimed to predict the risk factors related to histopathologic upgrade after endoscopic submucosal dissection (ESD) in patients with pre-ESD esophageal squamous low-grade intraepithelial neoplasm (LGIN). METHODS: A training cohort of 201 patients with biopsy-confirmed esophageal squamous LGIN and underwent ESD at a tertiary medical center between January 2017 and July 2019 were included. Risk factors for histological upgrade were identified using the least absolute shrinkage and selection operator (LASSO) regression. A nomogram was then established. Internal validation was evaluated by discrimination, calibration plot, and decision-curve analysis. Another cohort of 48 patients were prospectively collected from July 2019 to June 2021 for external validation of the nomogram. RESULTS: The rate of histological upgrade was 34.8% (70/201) and 27.1% (13/48) in the training and validation sets, respectively. LASSO regression identified that tumor area (mm2 ) per biopsy, Lugol's staining pattern, background coloration, and the circumferential range of the lesion were significantly associated with histological upgrade. The final nomogram attained favorable prediction efficacy in the training cohort (area under the receiver operating curve [AUROC] 0.96, 95% confidence interval [CI] 0.94-0.98) and validation cohort (AUROC 0.92, 95% CI 0.79 -0.99). This model generated well-fitted calibration and clinical-decision curves in both cohorts. CONCLUSIONS: The nomogram may better guide clinical decision on whether performing EDS or follow-up for suspicious lesions in patients with biopsy-confirmed esophageal squamous LGIN.


Assuntos
Carcinoma in Situ , Carcinoma de Células Escamosas , Ressecção Endoscópica de Mucosa , Neoplasias Esofágicas , Carcinoma in Situ/patologia , Carcinoma de Células Escamosas/cirurgia , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/cirurgia , Humanos , Nomogramas , Estudos Retrospectivos
9.
Microsc Res Tech ; 84(5): 1003-1011, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33615646

RESUMO

How to correctly and scientifically dispose of medicine residue on the basis of protecting the environment is an urgent problem to be solved due to the continuous generation of a large amount of waste medicine residue. In this paper, the application of waste medicine residue (large volume produced each year) as a precursor in producing a biochar that could adsorb Pb ion was reported. Biochar is a stable, aromatic, porous substance that is rich in carbon and prepared through pyrolysis of waste biomass under anaerobic conditions. In this study, medicine residue was used as raw material, and high-temperature sintering furnace was used to prepare medicine slag biochar at different temperatures of 200°C, 300°C, 400°C, 500°C, and 600°C. The resulting biochar was characterized by elemental analysis, Fourier transform infrared spectroscopy (FTIR), specific surface area analysis, field emission-scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), and Raman spectroscopy (RS). Experimental results showed that with the increase in pyrolysis temperature, the biochar structure was destroyed. The yield decreased as the temperature gradually decreased from 81.69% to 33.90%. With the increase in temperature, the pH, the ash, and the fixed carbon gradually increased, whereas the number of surface functional groups decreased. The quasi second order kinetic equation can better fit the kinetic characteristics of adsorbing Pb ion by biochar. In general, this study provides a valuable method for recycling medicine residue.


Assuntos
Chumbo , Pirólise , Adsorção , Carvão Vegetal , Temperatura
10.
Seizure ; 76: 143-152, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32087549

RESUMO

PURPOSE: Epilepsy affects more than 50 million people worldwide and its management can be complicated by comorbidities such as impaired renal function. To optimize epilepsy control in patients with kidney disease, clinicians need to be aware of how antiepileptic drugs (AEDs) are affected by impaired renal function and how the kidneys are affected by epilepsy management strategies. Herein we present a narrative review with systematic literature search to discuss the use of AEDs in patients with renal impairment, including those undergoing dialysis, as well as the nephrotoxic effects of some AEDs. We finally conclude the article by providing practical tips about our approach to using AEDs in the setting of renal disease. METHODS: A literature search targeting epilepsy management in patients with kidney disease was performed in MEDLINE database (1946 to 7th Jan 2019). RESULTS: A total of 1193 articles were found. After duplicate removal, title and abstract screening followed by full text screening, a total of 110 references were included in this review. Additional information was included from drug product monographs. CONCLUSION: The disposition of AEDs can be altered in patients with impaired renal function, leading to a higher risk of AED toxicity or therapy failure. Renal dosage adjustment and close monitoring is recommended. Although AED-induced nephrotoxicity is rare, it is unpredictable and clinicians need to vigilant about this possibility. In addition, AEDs renal adverse reactions and renal drug interactions should be considered when selecting an AED.

11.
Inflammation ; 43(1): 231-240, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31802382

RESUMO

Ellipticine, a natural product from Ochrosia elliptica, has been broadly investigated for its anticancer effects. Although inflammation has been clearly identified as a key factor in the onset and progression of cancer, the relationship between ellipticine and inflammation remains unknown. Hence, the aims of the present study were to assess the effects of ellipticine on the inflammatory responses to lipopolysaccharide (LPS)-induced macrophages and to potentially identify the underlying mechanisms involved. Viability testing showed that ellipticine was not significantly toxic to Raw264.7 cells and actually conveyed protective effects to LPS-stimulated Raw264.7 cells and human peripheral blood monocytes by decreasing the secretion of inflammatory factors (TNF-α and IL-6). The results of western blot analysis and electrophoretic mobility shift assays showed that ellipticine markedly suppressed LPS-induced activation of the JNK/AP-1 (c-Fos and c-Jun) signaling pathway, but not ERK/p38/NF-κB pathway (p65 and p50) activation. Furthermore, ellipticine reduced the inflammatory response and mortality in a mouse model of LPS-induced endotoxic shock. Collectively, these data indicate that ellipticine may be a potential therapeutic agent for the treatment of inflammation-associated diseases.


Assuntos
Anti-Inflamatórios/farmacologia , Elipticinas/farmacologia , Inflamação/prevenção & controle , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Choque Séptico/prevenção & controle , Fator de Transcrição AP-1/metabolismo , Adulto , Animais , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Humanos , Inflamação/induzido quimicamente , Inflamação/enzimologia , Inflamação/imunologia , Interleucina-6/metabolismo , Lipopolissacarídeos , Macrófagos/enzimologia , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células RAW 264.7 , Choque Séptico/induzido quimicamente , Choque Séptico/enzimologia , Choque Séptico/imunologia , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo
12.
Genes Chromosomes Cancer ; 47(8): 665-79, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18470900

RESUMO

Human embryonic stem cells (hESCs) during long-term culture acquire chromosomal changes similar to those occurring in tumorigenesis. This was raised concerns about the progression from hESCs to malignant cells. This study aimed to investigate the changes in chromosomes, cell phenotype, and genes in culture-adapted hESCs to ascertain whether tumorigenic transformation occurred. By cytogenetic analysis we found progressive karyotypic changes from simple to complex in chHES-3, one of the hESC lines established in our laboratory, during a long-term suboptimal culture. We further compared chHES-3 cells at different karyotypic stages in cell surface markers, in vivo differentiation, cell cycle, apoptosis, and gene expression profiles. We found that the karyotypically aberrant chHES-3 had higher S-phase fraction in cell cycle distributions and antiapoptosis ability. In vivo differentiation of karyotypically normal chHES-3 resulted in relatively mature teratoma, whereas karyotypically aberrant chHES-3 formed immature teratoma (grade III), in which more primary neural epithelium was revealed by pathological analysis. The microarray analysis and real-time PCR results showed that some oncogenes were upregulated in karyotypically aberrant chHES-3 cells, whereas the genes related to differentiation were downregulated, and that Wnt signal pathway was activated. In conclusion, chHES-3 cells underwent deregulation of self-renewal and dysfunction of related genes in long-term culture adaptation, leading to malignant transformation.


Assuntos
Transformação Celular Neoplásica , Células-Tronco Embrionárias/patologia , Técnicas de Cultura de Células , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Células Cultivadas , Análise Citogenética , Perfilação da Expressão Gênica , Humanos , Processos Neoplásicos , Fase S/genética
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(11): 3147-9, 2009 Nov.
Artigo em Zh | MEDLINE | ID: mdl-20102006

RESUMO

Hollyhock powder was digested by microwave digestion before determination. The eight trace elements, Fe, Cu, Zn, Mn, K, Ni, Ca and Mg, in hollyhock were determined by microwave FAAS. Standard curves method was used for the determination. The samples were digested with HNO3. The conditions of digestion were optimized. The effect of different microwave digestion conditions on the analysis results was reviewed, and the optimal condition for using atomic absorption spectrophotometry was determined. The experiments indicated that the content of trace elements of human needs, Mg, Ca, Fe, K etc. are highly enriched, the content of Mn and Zn is middling, and the content of Cu and Ni is low. The method is highly sensitive, convenient and speedy. The recovery (n = 6) is 92.25%-110.50%, and the RSDs (n = 6) are lower than 5%. The results are satisfactory.


Assuntos
Malvaceae/química , Espectrofotometria Atômica , Oligoelementos/análise , Micro-Ondas
14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(12): 3412-5, 2009 Dec.
Artigo em Zh | MEDLINE | ID: mdl-20210183

RESUMO

The Cichorium glandulosum Boiss et Huet is a traditional Uighur natural herbal medicine, but has not been analyzed and studied in terms of its metal elements. In the experiment, the Cichorium glandulosum Boiss et Huet powder was digested with HNO3 by microwave digestion before determination. The eight metal elements, potassium, nickel, calcium, magnesium, iron, manganese, copper and zinc, in Cichorium glandulosum Boiss et Huet were determined by FAAS. The working conditions, accuracy and precision of the method were studied. The linear correlations of standard curves are good (r = 0.999 1-0.999 9). The recovery (n = 6) is 92.25%-110.5%, and the RSD (n = 6) is 0.7%-3.88%. The results showed that there were comparatively rich metal elements, among which are comparatively high calcium (65.84 mg x g(-1)), iron (24.38 mg x g(-1)), magnesium (278.17 mg x g(-1)) and potassium (18.50 mg x g(-1)), in Cichorium glandulosum Boiss et Huet, and the contents of other elements are nickel of 0.004 38 mg x g(-1), manganese of 0.52 mg x g(-1), copper of 0.016 5 mg x g(-1) and zinc of 0.18 mg x g(-1). This provided useful data for discussing the relationship between the content of the metal elements in Cichorium glandulosum Boiss et Huet and its clinical application in cardiovascular and osteoporosis disease.


Assuntos
Asteraceae/química , Medicamentos de Ervas Chinesas/química , Metais/análise , Micro-Ondas
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(7): 1993-6, 2009 Jul.
Artigo em Zh | MEDLINE | ID: mdl-19798990

RESUMO

Comprehensive utilization of traditional Uighur medicine has been increasingly emphasized, and the relationship between metal elements and traditional Uighur medicine has attracted great attention, so it is quite important to determine the contents of traditional Uighur medicine. The Ziziphora clinopodioides Lam powder was digested with HNO3 by microwave digestion before determination. Ten metal elements in Ziziphora clinopodioides Lam were determined by FAAS. The work conditions, accuracy and precision of the method were studied. The linear correlations of standard curves are good (r = 0.999 0-0.999 8). The recovery (n = 6) is 95%-108%, and the RSD(n = 6) is 0.45%-1.53%. The results showed that there were comparatively rich metal elements, among which are comparatively high calcium, magnesium and potassium in Ziziphora clinopodioides Lam. The method offers traits of low detection limit, high sensitivity, speediness and exactness, and wasapplied to the determination of metal elements in samples with satisfactory results. It provided useful data for discussing the relationship between the content of the metal elements in Ziziphora clinopodioides Lam and clinical application of the Uighur medicine.


Assuntos
Lamiaceae/química , Metais/análise , Metais/química , Micro-Ondas , Calibragem , Lamiaceae/efeitos da radiação , Limite de Detecção , Ácido Nítrico/química , Soluções , Espectrofotometria Atômica
17.
Stem Cells Dev ; 16(2): 243-52, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17521236

RESUMO

Recently, the research of recombinant thrombopoietin (TPO) and its subsequent use in treating thrombocytopenia following radiation therapy and chemotherapy have become more important in clinics. Our study was to determine the feasibility of recombinant adeno-associated virus (rAAV)-mediated TPO gene transfer into bone marrow-derived mesenchymal stem cells (MSCs) and to evaluate the conditioned medium (CM) obtained from TPO-transduced human (h) hMSCs for promoting the process of megakaryocytopoiesis. We constructed recombinant adeno-associated viruses expressing TPO successfully, and TPO mRNA and protein were both strongly expressed in TPO-transduced hMSCs. There was no decrease in green fluorescent protein (GFP) fluorescence expression of the transduced cells with continuous passaged culturing in vitro. The CM of TPO-transduced hMSCs has been shown to enhance the number of CD41(+) cells and megakaryocytic progenitors (colony-forming unit-megakaryocyte) significantly as compared to the nontransduced control. In this study, a novel safe and efficient method of promoting the megakaryocytopoiesis was established following the TPO-transduced hMSCs. These results provide a basis for the future studies on hematopoietic regulation by hMSCs transfected with TPO.


Assuntos
Células da Medula Óssea/fisiologia , Dependovirus/metabolismo , Hematopoese/fisiologia , Megacariócitos/fisiologia , Células-Tronco Mesenquimais/fisiologia , Trombopoetina/metabolismo , Células da Medula Óssea/citologia , Células Cultivadas , Meios de Cultivo Condicionados/química , Dependovirus/genética , Humanos , Megacariócitos/citologia , Células-Tronco Mesenquimais/citologia , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Trombopoetina/genética
18.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 32(5): 742-6, 2007 Oct.
Artigo em Zh | MEDLINE | ID: mdl-18007063

RESUMO

OBJECTIVE: To investigate the transfection condition of Type 2 recombinant adeno-associated virus ( rAAV2) in human dendritic cells(DCs) which were induced from the bone marrow CD34+ hematopoietic stem /progenitor cells. METHODS: CD34+ hematopoietic stem /progenitor cells were purified from the bone marrow mononuclear cells by immunomagnetic beads, and the cells were cultured with IL-4 and GM-CSF and maturated by TNF-alpha on the 5th day. The rAAV2 /GFP was transfected into the induced cells at different time.The DCs were identified by electronic microscope. The expression of GFP was evaluated by flow cytometry and fluorescence microscope. RESULTS: The DCs were induced successfully. The typical morphologic characteristics of DCs were observed under the light microscope and transmission electronic microscope, and the typical phenotypes of DCs could be detected by flow cytometry. The expression rate of GFP gene on the 3rd day, the 5th day and after adding TNF-alpha was 0.45%, 13.54%, and 0.25%, respectively. CONCLUSION: DCs can be induced from the human bone marrow CD34+ hematopoietic stem /progenitor cells, and infected with the rAAV2 /GFP successfully. The longer the induction time of DCs, the higher the transfection efficiency of DC. The transfection efficiency of immature DC is higher than that of mature DC.


Assuntos
Células da Medula Óssea/citologia , Células Dendríticas/citologia , Proteínas de Fluorescência Verde/genética , Células-Tronco Hematopoéticas/citologia , Antígenos CD34 , Diferenciação Celular , Dependovirus/genética , Vetores Genéticos , Humanos , Transfecção
19.
Front Microbiol ; 7: 1622, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27799924

RESUMO

The gut microbiota is an important contributor to host health and fitness. Given its importance, microbiota composition should not be left to chance. However, what determines this composition is far from clear, with results supporting contributions of both environmental factors and host genetics. To gauge the relative contributions of host genetics and environment, specifically the microbial diversity, we characterized the gut microbiotas of Caenorhabditis species spanning 200-300 million years of evolution, and raised on different composted soil environments. Comparisons were based on 16S rDNA deep sequencing data, as well as on functional evaluation of gut isolates. Worm microbiotas were distinct from those in their respective soil environment, and included bacteria previously identified as part of the C. elegans core microbiota. Microbiotas differed between experiments initiated with different soil communities, but within each experiment, worm microbiotas clustered according to host identity, demonstrating a dominant contribution of environmental diversity, but also a significant contribution of host genetics. The dominance of environmental contributions hindered identification of host-associated microbial taxa from 16S data. Characterization of gut isolates from C. elegans and C. briggsae, focusing on the core family Enterobacteriaceae, were also unable to expose phylogenetic distinctions between microbiotas of the two species. However, functional evaluation of the isolates revealed host-specific contributions, wherein gut commensals protected their own host from infection, but not a non-host. Identification of commensal host-specificity at the functional level, otherwise overlooked in standard sequence-based analyses, suggests that the contribution of host genetics to shaping of gut microbiotas may be greater than previously realized.

20.
Infect Dis (Lond) ; 48(4): 303-309, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26585858

RESUMO

Background Alcohol intake has been suggested to have an impact on the development of many chronic diseases. How alcohol intake may modulate risk of Helicobacter pylori (H. pylori) infection, however, remains a subject open for investigation. A dose-response meta-analysis was performed of epidemiological studies to better quantify this relationship. Materials and methods Twelve observational articles were identified. The summary odds ratio (OR) and confidence intervals (CI) were calculated for alcohol drinkers vs non-drinkers. The summary OR estimates were obtained using the random-effects model and dose-response meta-analysis. Sub-group and sensitivity analysis were also conducted. Results The summary OR was 0.78 (95% CI = 0.69-0.89). The dose-response analysis demonstrated that for drinkers of 10, 15, 30, 60 and 96 g/day alcohol intake, the estimated ORs were 0.80 (95% CI = 0.76-0.85), 0.79 (95% CI = 0.75-0.84), 0.83 (95% CI = 0.78-0.87), 0.85 (95% CI = 0.78-0.93) and 0.87 (95% CI = 0.70-1.06), respectively, compared to non-drinkers. The inverse relationship between alcohol intake and H. pylori infection was consistent, regardless of sex, age, geographic areas, detection methods or beverage types. CONCLUSION: Evidence from these observational studies suggests that moderate alcohol intake is associated with a reduction in H. pylori infection of ∼ 22% and may facilitate elimination of H. pylori.


Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Infecções por Helicobacter/epidemiologia , Helicobacter pylori/isolamento & purificação , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Observacionais como Assunto , Razão de Chances , Fatores de Risco
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