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1.
Malar J ; 20(1): 124, 2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33653360

RESUMO

BACKGROUND: Thrombospondin-related adhesive protein (TRAP) is a transmembrane protein that plays a crucial role during the invasion of Plasmodium falciparum into liver cells. As a potential malaria vaccine candidate, the genetic diversity and natural selection of PfTRAP was assessed and the global PfTRAP polymorphism pattern was described. METHODS: 153 blood spot samples from Bioko malaria patients were collected during 2016-2018 and the target TRAP gene was amplified. Together with the sequences from database, nucleotide diversity and natural selection analysis, and the structural prediction were preformed using bioinformatical tools. RESULTS: A total of 119 Bioko PfTRAP sequences were amplified successfully. On Bioko Island, PfTRAP shows its high degree of genetic diversity and heterogeneity, with π value for 0.01046 and Hd for 0.99. The value of dN-dS (6.2231, p < 0.05) hinted at natural selection of PfTRAP on Bioko Island. Globally, the African PfTRAPs showed more diverse than the Asian ones, and significant genetic differentiation was discovered by the fixation index between African and Asian countries (Fst > 0.15, p < 0.05). 667 Asian isolates clustered in 136 haplotypes and 739 African isolates clustered in 528 haplotypes by network analysis. The mutations I116T, L221I, Y128F, G228V and P299S were predicted as probably damaging by PolyPhen online service, while mutations L49V, R285G, R285S, P299S and K421N would lead to a significant increase of free energy difference (ΔΔG > 1) indicated a destabilization of protein structure. CONCLUSIONS: Evidences in the present investigation supported that PfTRAP gene from Bioko Island and other malaria endemic countries is highly polymorphic (especially at T cell epitopes), which provided the genetic information background for developing an PfTRAP-based universal effective vaccine. Moreover, some mutations have been shown to be detrimental to the protein structure or function and deserve further study and continuous monitoring.


Assuntos
Malária Falciparum/parasitologia , Plasmodium falciparum/genética , Proteínas de Protozoários/genética , Epitopos , Guiné Equatorial/epidemiologia , Frequência do Gene , Variação Genética , Haplótipos , Humanos , Vacinas Antimaláricas , Malária Falciparum/epidemiologia , Malária Falciparum/imunologia , Plasmodium falciparum/imunologia , Polimorfismo Genético , Proteínas de Protozoários/química , Proteínas de Protozoários/imunologia , Seleção Genética
2.
Malar J ; 19(1): 245, 2020 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-32660484

RESUMO

BACKGROUND: Plasmodium falciparum circumsporozoite protein (PfCSP) is a potential malaria vaccine candidate, but various polymorphisms of the pfcsp gene among global P. falciparum population become the major barrier to the effectiveness of vaccines. This study aimed to investigate the genetic polymorphisms and natural selection of pfcsp in Bioko and the comparison among global P. falciparum population. METHODS: From January 2011 to December 2018, 148 blood samples were collected from P. falciparum infected Bioko patients and 96 monoclonal sequences of them were successfully acquired and analysed with 2200 global pfcsp sequences mined from MalariaGEN Pf3k Database and NCBI. RESULTS: In Bioko, the N-terminus of pfcsp showed limited genetic variations and the numbers of repetitive sequences (NANP/NVDP) were mainly found as 40 (35%) and 41 (34%) in central region. Most polymorphic characters were found in Th2R/Th3R region, where natural selection (p > 0.05) and recombination occurred. The overall pattern of Bioko pfcsp gene had no obvious deviation from African mainland pfcsp (Fst = 0.00878, p < 0.05). The comparative analysis of Bioko and global pfcsp displayed the various mutation patterns and obvious geographic differentiation among populations from four continents (p < 0.05). The global pfcsp C-terminal sequences were clustered into 138 different haplotypes (H_1 to H_138). Only 3.35% of sequences matched 3D7 strain haplotype (H_1). CONCLUSIONS: The genetic polymorphism phenomena of pfcsp were found universal in Bioko and global isolates and the majority mutations located at T cell epitopes. Global genetic polymorphism and geographical characteristics were recommended to be considered for future improvement of malaria vaccine design.


Assuntos
Plasmodium falciparum/genética , Polimorfismo Genético , Proteínas de Protozoários/genética , Guiné Equatorial , Haplótipos , Seleção Genética
3.
Toxicol Appl Pharmacol ; 384: 114775, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31669778

RESUMO

Acute promyelocytic leukemia (APL) is characterized by a reciprocal translocation between chromosomes 15 and 17, t(15;17), resulting in the expression of PML-RARα fusion protein, which disrupts the normal PML nuclear bodies (PML-NBs) to micro-speckled pattern, leading to loss of their original functions. Moreover, reformation of PML-NBs in APL by arsenic is considered as one of the important step for APL treatment. Leptomycin B (LMB), a nuclear export inhibitor, is commonly used to inhibit the proteins exporting from the nucleus to the cytoplasm. In the present study, we found that LMB could induce the reformation of PML-NBs in leukemia NB4 cells as well as in APL blast cells from the patients, implying that nuclear shuttle proteins might be involved in the reformation of PML-NBs. Herein, we further found that LMB totally lost the ability to induce PML-NBs reformation when the endogenous PML gene was knocked out, indicating that endogenous PML protein is probably involved in the reformation of PML-NBs. More interestingly, among all PML isoforms (i.e., seven isoforms), reformation of PML-NBs was only observed when co-transfection of PML-RARα with PML-I after LMB treatment. Similarly, deletion of nuclear export signal (NES) of PML-I could also reform PML-NBs, suggesting that the protein level of endogenous PML-I in nucleus is important for the reformation of PML-NBs that interfered by PML-RARα fusion protein. Additionally, LMB has synergistic effect with iAsIII on enhancing PML-RARα fusion protein degradation, and it might provide new insight into APL treatment at clinical level in the near future.


Assuntos
Antineoplásicos/farmacologia , Leucemia Promielocítica Aguda/tratamento farmacológico , Proteínas de Fusão Oncogênica/metabolismo , Proteína da Leucemia Promielocítica/metabolismo , Antineoplásicos/uso terapêutico , Trióxido de Arsênio/farmacologia , Trióxido de Arsênio/uso terapêutico , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Núcleo Celular/patologia , Ensaios de Seleção de Medicamentos Antitumorais , Sinergismo Farmacológico , Ácidos Graxos Insaturados/farmacologia , Ácidos Graxos Insaturados/uso terapêutico , Humanos , Leucemia Promielocítica Aguda/sangue , Leucemia Promielocítica Aguda/genética , Leucemia Promielocítica Aguda/patologia , Leucócitos Mononucleares , Proteínas de Fusão Oncogênica/genética , Cultura Primária de Células , Isoformas de Proteínas/metabolismo , Proteólise/efeitos dos fármacos
4.
Ecotoxicol Environ Saf ; 150: 251-259, 2018 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-29288906

RESUMO

In this paper, the adsorption behaviors of Cu(II) from the aqueous solution using rape straw powders were studied. The effects of initial Cu(II) concentration, pH range and absorbent dosage on the adsorption efficiency of Cu(II) by rape straw powder were investigated by Box-Behnken Design based on response surface methodology. The values of coefficient constant of the nonlinear models were 0.9997, 0.9984 and 0.9944 for removal Cu(II) from aqueous solution using rape straw shell, seed pods and straw pith core, respectively, which could navigate the design space for various factors on effects of biosorption Cu(II) from aqueous solution. The various factors of pH and biosorbents dosage were the key factors that affecting the removal efficiency of Cu(II) from aqueous solution. The biosorption equilibrium data presented its favorable monolayer adsorption Cu(II) onto shell, seed pods and straw pith core, respectively. The pseudo-second order kinetic model was the proper approach to determine the adsorption kinetics. The biosorption of Cu(II) onto surfaces of rape straw powders were confirmed and ion-exchanged in the adsorption process by energy dispersive spectrometer. The critical groups, -OH, -CH, -NH3+, -CH3, -NH and -C-O, exhibited by the infrared spectra results, changed to suggest that these groups played critical roles, especially -CH3 in the adsorption of copper ions onto rape straw powders. The study provided evidences that rape straw powders can be used for removing Cu(II) from aqueous water.


Assuntos
Brassica/química , Cobre/análise , Modelos Teóricos , Poluentes Químicos da Água/análise , Adsorção , Concentração de Íons de Hidrogênio , Íons , Cinética , Pós , Soluções , Propriedades de Superfície
5.
Anal Chim Acta ; 1315: 342797, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38879209

RESUMO

BACKGROUND: Harmful algal blooms (HABs), caused by the rapid proliferation or aggregation of microorganisms, are catastrophic for the environment. The Prymnesium parvum is a haptophyte algal species that is found worldwide and is responsible for extensive blooms and death of larval amphibians and bivalves, causing serious negative impacts on the ecological environment. For the prevention and management of environmental pollution, it is crucial to explore and develop early detection strategies for HABs on-site using simple methods. The major challenge related to early detection is the accurate and sensitive detection of algae present in low abundance. RESULTS: Herein, recombinase polymerase amplification (RPA) was combined with clustered regularly interspaced short palindromic repeats and Cas12a protein (CRISPR-LbaCas12a) systems, and the lateral flow dipstick (LFD) was used for the first time for early detection of P. parvum. The internal transcribed spacer (ITS) of P. parvum was selected as the target sequence, and the concentration of single-strand DNA reporters, buffer liquid system, reaction time, and amount of gold particles were optimized. The RPA-CRISPR-LbaCas12a-LFD approach demonstrated highly specificity during experimental testing, with no cross-reaction against different microalgae used as controls. In addition, the lowest detection limit was 10,000 times better than the lowest detection limit of the standalone RPA approach. The feasibility and robustness of this approach were further verified by using the different environmental samples. It also observed that P. parvum are widely distributed in Chinese Sea, but the cell density of P. parvum is relatively low (<0.1 cells/mL). SIGNIFICANCE: The developed approach has an excellent specificity and offers 10,000 times better sensitivity than the standalone RPA approach. These advantages make this approach suitable for early warning detection and prevention of HAB events in environmental water. Also, the outcomes of this study could promote a shift from traditional laboratory-based detection to on-site monitoring, facilitating early warning against HABs.


Assuntos
Sistemas CRISPR-Cas , Sistemas CRISPR-Cas/genética , Limite de Detecção , Técnicas de Amplificação de Ácido Nucleico/métodos , Recombinases/metabolismo , Proliferação Nociva de Algas , Ouro/química , Proteínas Associadas a CRISPR/genética , Endodesoxirribonucleases/genética , Proteínas de Bactérias/genética
6.
Inorg Chem ; 50(19): 9345-53, 2011 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-21902231

RESUMO

A series of dendronized-Ru(2) compounds were prepared using the Cu(I)-catalyzed 1,3-dipolar cycloaddition (click reaction) between the terminal azides of azidopoly(benzyl ether) dendrons ([D(n)]-N(3), n = 0-3) and Ru(2) units bearing one or two terminal ethynes, Ru(2)(D(3,5-Cl(2)Ph)F)(4-m)(DMBA-4-C(2)H)(m)Cl with m = 1 and 2, and D(3,5-Cl(2)Ph)F and DMBA-4-C(2)H as N,N'-bis(3,5-dichloro-phenyl)formamidinate and N,N'-dimethyl-4-ethynylbenzamidinate, respectively. The resultant Ru(2)(D(3,5-Cl(2)Ph)F)(4-m)(DMBA-D(n))(m)Cl compounds were further functionalized by the axial ligand displacement of Cl by -C(2)Ph to yield new compounds Ru(2)(D(3,5-Cl(2)Ph)F)(4-m)(DMBA-D(n))(m)(C(2)Ph)(2) (where m = 1 and 2; n = 0 and 1). All Ru(2) compounds reported herein were analyzed via mass spectrometry, voltammetry, and UV-visible and fluorescence spectroscopy. Density-functional theory (DFT) calculations were performed on a model compound to gain more insight into the molecular orbital energy levels possibly associated with the photophysical data obtained and presented herein.

7.
Fa Yi Xue Za Zhi ; 27(2): 139-41, 2011 Apr.
Artigo em Zh | MEDLINE | ID: mdl-21604455

RESUMO

Transcranial magnetic stimulation-motor evoked potential (TMS-MEP) test is one of the electrophysiological examination methods to evaluate the function of central nervous system. The value of the TMS-MEP has been recognized by some clinical forensic workers recently. This article reviews the principle and advantages of TMS-MEP and its application in functional evaluation of central nervous system and clinical treatment. The value of TMS-MEP in forensic medicine, especially in objective assessment of muscle strength after injury of central nervous system is also discussed.


Assuntos
Doenças do Sistema Nervoso Central/fisiopatologia , Potencial Evocado Motor/fisiologia , Medicina Legal/métodos , Estimulação Magnética Transcraniana , Doenças do Sistema Nervoso Central/diagnóstico , Avaliação da Deficiência , Humanos , Monitorização Fisiológica/métodos , Córtex Motor/fisiologia , Córtex Motor/fisiopatologia , Músculo Esquelético/fisiologia , Músculo Esquelético/fisiopatologia , Condução Nervosa/fisiologia , Valor Preditivo dos Testes , Índice de Gravidade de Doença , Traumatismos da Medula Espinal/diagnóstico , Traumatismos da Medula Espinal/fisiopatologia
8.
Cytokine ; 49(2): 194-200, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19819722

RESUMO

The anti-inflammatory effects of high density lipoprotein (HDL) are well described, however, such effects of Apolipoprotein A-I (ApoA-I) are less studied. Building on our previous study, we further explored the mechanism of anti-inflammatory effects of ApoA-I, and focused especially on the interaction between monocyte and endothelial cells and plasma HDL inflammatory index in LPS-challenged rabbits. Our results show that ApoA-I significantly decreased LPS-induced MCP-1 release from THP-1 cells and ox-LDL-induced THP-1 migration ratio (P<0.01, respectively). ApoA-I significantly decreased sL-selectin, sICAM-1 and sVCAM-1 release (P<0.01, P<0.01, P<0.05, respectively) from LPS-stimulated THP-1 cells. Furthermore, ApoA-I significantly inhibited LPS-induced CD11b and VCAM-1 expression on THP-1 cells (P<0.01, P<0.05, respectively). ApoA-I diminished LPS-induced mCD14 expression (P<0.01) and NFkappaB nuclear translocation in THP-1 cells. After single dose treatment of ApoA-I, the value of plasma HDL inflammatory index in LPS-challenged rabbits was improved significantly (P<0.05). These results suggest that ApoA-I can inhibit chemotaxis, adhesion and activation of human monocytes and improve plasma HDL inflammatory index with presenting beneficial anti-inflammatory effects.


Assuntos
Apolipoproteína A-I/farmacologia , Adesão Celular/efeitos dos fármacos , Quimiotaxia/efeitos dos fármacos , Lipoproteínas HDL , Monócitos/efeitos dos fármacos , Monócitos/fisiologia , Animais , Apolipoproteína A-I/metabolismo , Linhagem Celular Tumoral , Humanos , Lipoproteínas HDL/sangue , Lipoproteínas HDL/imunologia , Masculino , Monócitos/citologia , NF-kappa B/metabolismo , Coelhos , Distribuição Aleatória
9.
Zhonghua Gan Zang Bing Za Zhi ; 18(10): 740-4, 2010 Oct.
Artigo em Zh | MEDLINE | ID: mdl-21059289

RESUMO

OBJECTIVE: To study the effects of estrogen receptor (ER) alpha gene polymorphism on the migration of T lymphocyte subsets and related cytokines in the female patients with primary biliary cirrhosis(PBC). METHODS: This study was conducted with sixty female PBC patients without treatment as the study group and fifty-two healthy people wtih sex and age met the requirements of the study as the control group. The polymorphism of restriction enzyme cutting site of Xba I and Pvu II in intron 1 of ERa gene was detected by polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP). CD4+, CD8+, CD4+CD25+ and CD4+CD28- T lymphocytes in peripheral blood were quantitatively detected by flow cytometry. RT-PCR method was used to detect the expression of TNFa, IL-2, IFNgamma, IL-4, IL-6 and IL-10 in peripheral mononuclear cells. RESULTS: The positive rate of Pp in ERa gene Pvu II enzyme gene subtypes of female PBC patients was significantly greater than that of the control group, and the positive rate of pp gene subtype was significantly smaller than that of the control group (X2 = 7.2880, P = 0.0261). The difference of Xba I genotype and allele frequency between the female PBC patients group and the control group was not of statistical significance (X2 = 6.5382, P = 0.5833). The proportion of CD4+ T in T lymphocytes of PBC patients was increased to 45.31%+/-5.26%, compared with 33.81%+/-3.87% in the control group; and the proportion of CD8+ T lymphocytes was decreased to 27.78%+/-1.43 % from 31.83%+/-1.73% in the control group. In comparison with the control group, the proportion of CD4+CD25+ T lymphocytes decreased significantly, while that of CD4+CD28- T lymphocytes rose significantly. The expression levels of TNFa, IL-2 and IFNgamma mRNA were 0.59+/-0.19, 0.71+/-0.29 and 0.67+/-0.21 respectively, which were significantly higher than that in the control group (0.22+/-0.13, 0.31+/-0.14, 0.27+/-0.13) (t = 6.93, 5.07, 7.01, P value less than 0.01); the expression level of IL-6 mRNA was increased to 0.45+/-0.21 from 0.34+/-0.16 in the control group (t = 1.84, P value less than 0.05); and the difference of the expression levels of IL-4 and IL-10 mRNA between two groups was not of statistical significance. CONCLUSION: Pp of gene Pvu II was a genetically susceptible genotype in female PBC patients, and the allele p was a susceptible gene. Th1 cell subsets and related cytokines were dominant in peripheral blood of PBC patients. As a background of genetic susceptibility, ERa gene polymorphism could affect the shift of T lymphocyte subsets and the expression of the related cytokines in PBC patients.


Assuntos
Receptor alfa de Estrogênio/genética , Cirrose Hepática Biliar/genética , Subpopulações de Linfócitos T/metabolismo , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Interferon gama/metabolismo , Interleucina-2/metabolismo , Interleucina-6/metabolismo , Cirrose Hepática Biliar/metabolismo , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Fator de Necrose Tumoral alfa/metabolismo
10.
Zhonghua Gan Zang Bing Za Zhi ; 18(7): 511-5, 2010 Jul.
Artigo em Zh | MEDLINE | ID: mdl-20678441

RESUMO

OBJECTIVES: To investigate the prevalence of hepatitis B virus (HBV) genotypes and the association with hepatocellular carcinoma (HCC) or basal core promoter (BCP) mutation in Qidong, China. METHODS: The whole genome of HBV or X gene sequences were obtained from serum samples of HBV infected patients by using PCR and direct sequencing methods. Phylogenetic tree was constructed to determine the genotypes or subgenotypes of HBV. RESULTS: According to the phylogenetic tree constructed from full-length sequence of HBV, genotype C2 was predominant in Qidong area. It was prevalent in 44 out of the 48 cases (91.7%), whereas genotype B2 only existed in 4 cases (8.3%). No other genotypes or recombinant types were found in Qidong patients. The result of genotyping based on X gene sequence confirmed the above observation. In a total of 182 samples, 169 (92.9%) showed genotype C2 and 10 (5.5%) showed genotype B2. There were 3 (1.6%) patients showed a coinfection with C2 and B2. The infection rate of genotype C in Qidong was significantly higher than that in neighboring city Shanghai (chi(2) = 12.252, P less than 0.01). There was no significant difference of genotype distribution between HCC and chronic hepatitis groups (P is more than 0.05). The frequency of T1762/A1764 double mutation in genotype C2 (70.3%) was significantly higher than that in genotype B2 (30.8%, P less than 0.05). The other two types of point mutation which also occurred in BCP, i.e. T1766 and A1768, were only seen in genotype C2. CONCLUSION: (1) Genotype C2 is the predominant genotype in Qidong, China. (2) There is no association between genotype C and HCC in Qidong. (3) Genotype C has a higher prevalence of BCP mutation than genotype B.


Assuntos
Carcinoma Hepatocelular/virologia , Vírus da Hepatite B/genética , Neoplasias Hepáticas/virologia , Proteínas do Core Viral/genética , Adolescente , Adulto , Idoso , Carcinoma Hepatocelular/epidemiologia , Criança , Pré-Escolar , China/epidemiologia , DNA Viral/genética , Feminino , Genótipo , Hepatite B Crônica/virologia , Humanos , Neoplasias Hepáticas/epidemiologia , Masculino , Pessoa de Meia-Idade , Mutação , Prevalência , Adulto Jovem
11.
IEEE Trans Neural Netw Learn Syst ; 31(12): 5231-5244, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32175875

RESUMO

Recently, the dynamical behaviors of coupled neural networks (CNNs) with and without reaction-diffusion terms have been widely researched due to their successful applications in different fields. This article introduces some important and interesting results on this topic. First, synchronization, passivity, and stability analysis results for various CNNs with and without reaction-diffusion terms are summarized, including the results for impulsive, time-varying, time-invariant, uncertain, fuzzy, and stochastic network models. In addition, some control methods, such as sampled-data control, pinning control, impulsive control, state feedback control, and adaptive control, have been used to realize the desired dynamical behaviors in CNNs with and without reaction-diffusion terms. In this article, these methods are summarized. Finally, some challenging and interesting problems deserving of further investigation are discussed.


Assuntos
Redes Neurais de Computação , Algoritmos , Retroalimentação , Lógica Fuzzy , Processos Estocásticos , Incerteza
12.
Infect Drug Resist ; 13: 1203-1212, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32431521

RESUMO

PURPOSE: Antimalarial drug resistance is one of the major challenges in global efforts to control and eliminate malaria. In 2006, sulfadoxine-pyrimethamine (SP) replaced with artemisinin-based combination therapy (ACT) on Bioko Island, Equatorial Guinea, in response to increasing SP resistance, which is associated with mutations in the dihydrofolate reductase (Pfdhfr) and dihydropteroate synthase (Pfdhps) genes. PATIENTS AND METHODS: To evaluate the trend of molecular markers associated with SP resistance on Bioko Island from 2011 to 2017, 179 samples collected during active case detection were analysed by PCR and DNA sequencing. RESULTS: Pfdhfr and Pfdhps gene sequences were obtained for 90.5% (162/179) and 77.1% (138/179) of the samples, respectively. For Pfdhfr, 97.5% (158/162), 95.7% (155/162) and 98.1% (159/162) of the samples contained N51I, C59R and S108N mutant alleles, respectively. And Pfdhps S436A, A437G, K540E, A581G, and A613S mutations were observed in 25.4% (35/138), 88.4% (122/138), 5.1% (7/138), 1.4% (2/138), and 7.2% (10/138) of the samples, respectively. Two classes of previously described Pfdhfr-Pfdhps haplotypes associated with SP resistance and their frequencies were identified: partial (IRNI-SGKAA, 59.4%) and full (IRNI-SGEAA, 5.5%) resistance. Although no significant difference was observed in different time periods (p>0.05), our study confirmed a slowly increasing trend of the frequencies of these SP-resistance markers in Bioko parasites over the 7 years investigated. CONCLUSION: The findings reveal the general existence of SP-resistance markers on Bioko Island even after the replacement of SP as a first-line treatment for uncomplicated malaria. Continuous molecular monitoring and additional control efforts in the region are urgently needed.

13.
Mol Genet Genomic Med ; 8(2): e1061, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31872983

RESUMO

BACKGROUND: Glucose-6-phosphate dehydrogenase (G6PD) is an essential enzyme that protects red blood cells from oxidative damage. Although G6PD-deficient alleles appear to confer a protective effect of malaria, the link with clinical protection against Plasmodium infection is conflicting. METHODS: A case-control study was conducted on Bioko Island, Equatorial Guinea and further genotyping analysis used to detect natural selection of the G6PD A- allele. RESULTS: Our results showed G6PD A- allele could significantly reduce the risk of Plasmodium falciparum infection in male individuals (adjusted odds ratio [AOR], 0.43; 95% confidence interval [CI], 0.20-0.93; p < .05) and homozygous female individuals (AOR, 0.11; 95% CI, 0.01-0.84; p < .05). Additionally, the parasite densities were significantly different in the individuals with different G6PD A- alleles and individual levels of G6PD enzyme activity. The pattern of linkage disequilibrium and results of the long-range haplotype test revealed a strong selective signature in the region encompassing the G6PD A- allele over the past 6,250 years. The network of inferred haplotypes suggested a single origin of the G6PD A- allele in Africans. CONCLUSION: Our findings demonstrate that glucose-6-phosphate dehydrogenase (G6PD) A- allele could reduce the risk of P. falciparum infection in the African population and indicate that malaria has a recent positive selection on G6PD A- allele.


Assuntos
Alelos , Glucosefosfato Desidrogenase/genética , Malária/genética , População/genética , Seleção Genética , Adolescente , Adulto , População Negra/genética , Criança , Pré-Escolar , Feminino , Guiné , Homozigoto , Humanos , Lactente , Ilhas , Desequilíbrio de Ligação , Masculino , Plasmodium falciparum/patogenicidade , Polimorfismo de Nucleotídeo Único
14.
Metallomics ; 11(12): 2089-2096, 2019 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-31670356

RESUMO

Arsenic trioxide (As2O3) is one of the most effective drugs for the treatment of acute promyelocytic leukemia (APL), and induces the degradation of chimeric oncoprotein PML/RARα (P/R) and APL cell differentiation. Recent evidence has suggested that P/R fusion protein degradation by arsenic occurs through two steps, namely, rapid solubility change/shift of the P/R fusion protein following arsenic treatment (i.e., transfer of P/R protein from the soluble fraction to the insoluble pellet fraction), and subsequent degradation of these insoluble proteins. However, there is little information regarding the reversibility of arsenic induced P/R fusion protein solubility change as well as protein degradation in the insoluble fraction after removing arsenic. In this study, we used APL cell line NB4 or P/R and PML over-expressed 293T cells as well as HeLa cells to reveal the solubility change of P/R and PML by arsenic exposure, and further determined the fate of these insoluble proteins after the removal of arsenic. Here, for the first time, we found that arsenic induced P/R or PML protein solubility change is an irreversible process. Once arsenic induces a P/R or PML protein solubility change, these insoluble proteins could be degraded by the proteasomal pathway even without continuous arsenic treatment. However, PML and P/R proteins can be newly synthesized after the removal of arsenic, suggesting that great caution should be taken in the clinical therapy of APL patients before ending arsenic treatment.


Assuntos
Trióxido de Arsênio/farmacologia , Diferenciação Celular/efeitos dos fármacos , Leucemia Promielocítica Aguda/tratamento farmacológico , Proteínas de Fusão Oncogênica/metabolismo , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Células HEK293 , Células HeLa , Humanos , Leucemia Promielocítica Aguda/metabolismo , Leucemia Promielocítica Aguda/patologia , Proteínas de Fusão Oncogênica/química , Proteínas de Fusão Oncogênica/genética , Solubilidade/efeitos dos fármacos
15.
Liver Int ; 28(10): 1446-57, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18466260

RESUMO

BACKGROUND/AIMS: Platelet-derived growth factor (PDGF) is the strongest stimulator of the proliferation of hepatic stellate cells (HSCs). PDGF receptor beta subunit (PDGFR-beta) is acquired on HSCs proliferation induced by PDGF. In this study, we aim to investigate the effect of PDGFR-beta small interference RNA (siRNA) on experimental hepatic fibrosis. METHODS: We constructed a PDGFR-beta siRNA expression plasmid and investigated its effect on the activation of HSCs. Bromodeoxyuridine incorporation was performed to investigate the effect of PDGFR-beta siRNA on HSCs proliferation. A hydrodynamics-based transfection method was used to deliver PDGFR-beta siRNA to rats with hepatic fibrosis. The distribution of transgenes in the liver was observed by immunofluorescence. The antifibrogenic effect of PDGFR-beta siRNA was investigated pathologically. RESULTS: Platelet-derived growth factor receptor-beta subunit siRNA could significantly downregulate PDGFR-beta expression, suppress HSCs activation, block the mitogen-activated protein kinase signalling pathway and inhibit HSCs proliferation in vitro. PDGFR-beta siRNA expression plasmid could be delivered into activated HSCs by the hydrodynamics-based transfection method, and remarkably improve the liver function of the rat model induced by dimethylnitrosamine and bile duct ligation. Furthermore, the progression of fibrosis in the liver was significantly suppressed by PDGFR-beta siRNA in both animal models. CONCLUSIONS: Platelet-derived growth factor receptor-beta subunit siRNA may be presented as an effective antifibrogenic gene therapeutic method for hepatic fibrosis.


Assuntos
Regulação da Expressão Gênica/genética , Terapia Genética/métodos , Células Estreladas do Fígado/metabolismo , Cirrose Hepática Experimental/terapia , Interferência de RNA , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Animais , Western Blotting , Bromodesoxiuridina , Linhagem Celular , Proliferação de Células , Primers do DNA/genética , Imunofluorescência , Cirrose Hepática Experimental/genética , Cirrose Hepática Experimental/metabolismo , RNA Interferente Pequeno/genética , Ratos , Ratos Sprague-Dawley , Receptor beta de Fator de Crescimento Derivado de Plaquetas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção/métodos
16.
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue ; 20(2): 69-71, 2008 Feb.
Artigo em Zh | MEDLINE | ID: mdl-18279586

RESUMO

OBJECTIVE: To investigate the expression of scavenger receptor class A (SR-A) in lung tissue and alveolar macrophage (AM) in mice with acute lung injury (ALI) induced by lipopolysaccharide (LPS). METHODS: The model of ALI was reproduced by intraperitoneal (ip) injection of LPS (5 mg/kg), and the expression of SR-A was observed in lung tissue and AM, and the expression and distribution of J774 A.1 were also studied by using mouse macrophage line. RESULTS: Partial pressure of oxygen in artery (PaO(2)) of lung tissue in LPS groups was significantly lower while wet/dry weight (W/D) ratio was higher than those in normal saline control group (both P<0.01). SR-A was widely expressed in murine lung, including AM, pulmonary vascular endothelial cells, vascular smooth muscle cells, lung epithelial cells and polymorphonuclear neutrophils. Immunohistochemical staining showed that, during the course of development of ALI in mice, the expression of SR-A was gradually down-regulated with the elapse of time after ip injection of LPS, The same result was seen in the isolated AM, and especially marked in group 4 hours and group 8 hours. In vitro, the expression of SR-A on J774 A.1 cells decreased was also down-regulated when treated with LPS. CONCLUSION: SR-A was widely expressed in murine lung. During the course of ALI, the expression of SR-A in the murine lung and AM is down-regulated, which may be induced by LPS.


Assuntos
Lesão Pulmonar Aguda/metabolismo , Lipopolissacarídeos/toxicidade , Pulmão/metabolismo , Receptores Depuradores Classe A/metabolismo , Animais , Modelos Animais de Doenças , Feminino , Macrófagos Alveolares/metabolismo , Masculino , Camundongos , Distribuição Aleatória
17.
Zhonghua Gan Zang Bing Za Zhi ; 13(1): 9-11, 2005 Jan.
Artigo em Zh | MEDLINE | ID: mdl-15670482

RESUMO

OBJECTIVE: A study on the value of antimitochondrial antibody (AMA) and its subtypes anti-M2, anti-M4, and anti-M9 in diagnosing primary biliary cirrhosis (PBC). METHODS: Antimitochondrial antibody was detected by indirect immunofluorescence and anti-M2, anti-M4 and anti-M9 by Western blotting. AMA and anti-M2 of 78 PBC patients, of 35 non-PBC hepato-biliary disease patients and 20 healthy controls were studied and anti-M2, anti-M4 and anti-M9 were studied in 30 of the 78 PBC patients. RESULTS: 96.2% (75/78) of PBC patients were AMA positive and 94.9% (74/78) of PBC patients were anti-M2 positive. Only three among the 35 non-PBC patients were positive for AMA (one with very low titre). None of the 35 non-PBC patients was anti-M2 positive. AMA and anti-M2 were negative in all the healthy controls. Among the 30 anti-M2 positive patients, 16 patients were anti-M4 positive (16/30, 53.3%) and 4 patients were anti-M9 positive (4/30, 13.3%). CONCLUSION: AMA and its subtypes (special anti-M2) are important sero-immunological markers for the diagnosis of PBC.


Assuntos
Autoanticorpos/sangue , Cirrose Hepática Biliar/diagnóstico , Mitocôndrias Hepáticas/imunologia , Autoanticorpos/classificação , Feminino , Humanos , Cirrose Hepática Biliar/imunologia , Masculino
18.
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue ; 17(9): 515-8, 2005 Sep.
Artigo em Zh | MEDLINE | ID: mdl-16146592

RESUMO

OBJECTIVE: To investigate the role of Fas and FasL expression in apoptosis of pulmonary artery smooth muscle cells (PASMCs) in hypoxia induced by inhibition of Na(+)/H(+) exchanger isoform-1 (NHE-1) in rat. METHODS: The cells were cultured in hypoxia (<1% O(2)) for 2, 6, 12, 24 and 48 hours respectively. Then cell apoptosis was observed with terminal deoxynudeotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL). The changes in fas and fasl mRNA expression in PASMCs were detected by semi-quantitative reverse transcription-polymerase chain reaction (sqRT-PCR) in vitro. The expression of Fas and FasL protein in cells was determined immunohistochemically. RESULTS: No significant changes in the expression of fas/fasL mRNA and protein between cells transfected with NHE-1 ribozyme gene and cells transfected with pLXSN, or non-transfected control in hypoxia. CONCLUSION: Apoptosis of PASMCs induced by NHE-1 inhibition may occur independently of Fas/FasL death pathway.


Assuntos
Apoptose , Proteína Ligante Fas/metabolismo , Miócitos de Músculo Liso/patologia , Trocadores de Sódio-Hidrogênio/metabolismo , Receptor fas/metabolismo , Animais , Hipóxia Celular/fisiologia , Células Cultivadas , Proteína Ligante Fas/genética , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/metabolismo , Artéria Pulmonar/citologia , RNA Mensageiro/genética , Ratos , Transfecção , Receptor fas/genética
19.
J Dig Dis ; 16(11): 665-74, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26474237

RESUMO

OBJECTIVE: To evaluate the efficacy, safety and tolerability of different doses of rifaximin in Chinese patients with liver cirrhosis. METHODS: This random prospective study included a screening visit, a 2-week treatment period and a subsequent 4-week observation phase. Patients with liver cirrhosis were randomly assigned to a low-dose rifaximin group, a high-dose rifaximin group and the control group in a ratio of 1:1:1. The low-dose and high-dose groups received 400 mg or 600 mg rifaximin per 12 h for 2 weeks, respectively. All other therapeutic strategies remained unchanged in the three groups as long as possible. RESULTS: In total, 60 patients with liver cirrhosis were screened and 43 of them met the eligibility criteria. After 2-week treatment serum endotoxin levels in the low-dose (1.1 ± 0.8 EU/mL) and high-dose rifaximin groups (1.0 ± 0.8 EU/mL) were significantly lower than that in the control group (2.5 ± 1.8 EU/mL), while no significant difference was found between the two rifaximin-treated groups. The effect of high-dose rifaximin on endotoxemia lasted for at least 4 weeks after drug withdrawal. A significant reduction in the abundance of the Veillonellaceae taxa and an increase in the abundance of Bacteroidaceae were shown after 2 weeks of rifaximin therapy. The incidence of adverse events and severe adverse events was similar among the three groups. CONCLUSION: Low-dose (800 mg/day) rifaximin could be analogous to high-dose (1200 mg/day) rifaximin to reduce the serum endotoxin level after 2 weeks of treatment.


Assuntos
Antibacterianos/administração & dosagem , Endotoxemia/tratamento farmacológico , Cirrose Hepática/complicações , Rifamicinas/administração & dosagem , Adolescente , Adulto , Idoso , Antibacterianos/efeitos adversos , Antibacterianos/uso terapêutico , Citocinas/sangue , Relação Dose-Resposta a Droga , Endotoxemia/sangue , Endotoxemia/etiologia , Feminino , Humanos , Masculino , Microbiota/efeitos dos fármacos , Pessoa de Meia-Idade , Estudos Prospectivos , Rifamicinas/efeitos adversos , Rifamicinas/uso terapêutico , Rifaximina , Receptores Toll-Like/sangue , Adulto Jovem
20.
Zhonghua Gan Zang Bing Za Zhi ; 11(6): 331-3, 2003 Jun.
Artigo em Zh | MEDLINE | ID: mdl-12837207

RESUMO

OBJECTIVE: To explore the proliferation of primary cultured rats hepatocytes after delivery of exogenous hepatocyte growth factor (HGF) gene which was inserted into the genome of replication-deficient recombinant adenovirus vector. METHODS: The recombinant adenovirus-AdHGF which could express HGF was generated by homologous recombination. After the HGF gene was delivered into the hepatocytes, the expression of both HGF and c-met/HGF receptor mRNA in the cells was detected by RT-PCR and the level of HGF in the culture supernatant was also assayed by ELISA. On the other hand, cell proliferation was compared between before and after delivery of the HGF gene by MTS assay and the percentages of cell cycles were analyzed by flow cytometry. In addition, the expression of proliferating cell nuclear antigen (PCNA) was determined by immunocytofluorescent stain. RESULTS: 4 x 10(10) efu/ml titer of AdHGF was obtained after recombination, RT-PCR indicated that the expression of HGF mRNA in hepatocytes increased on the third day after infected by the viruses and c-met/HGF receptor mRNA was also up-regulated. The HGF level in the culture supernatant assayed by ELISA was (5,939.0+/-414.39) pg/ml, which was much higher than that in the control (208.1pg/ml+/-37.20pg/ml, F=13.661, P<0.01). In addition, the proliferation of hepatocytes infected with AdHGF increased significantly according to MTS method (F>or=15.158, P<0.01) and more hepatocytes in G0/G1 stages changed into S stage (chi2=41.616, P<0.01), accordingly, PCNA index increased from 6.42+/- 1.88 to 14.56+/-2.85 (F=42.122, P<0.01). THE RESULTS: show that HGF gene delivered into hepatocytes by AdHGF can be expressed with high efficiency in the cells, which can stimulate hepatocytes proliferation. It may be an effective tool for hepatocyte transplantation by gene modified donor hepatocytes.


Assuntos
Proliferação de Células/efeitos dos fármacos , Fator de Crescimento de Hepatócito/biossíntese , Fator de Crescimento de Hepatócito/farmacologia , Hepatócitos/efeitos dos fármacos , Adenoviridae/genética , Adenoviridae/metabolismo , Animais , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Vetores Genéticos , Fator de Crescimento de Hepatócito/genética , Hepatócitos/citologia , Hepatócitos/metabolismo , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/farmacologia
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