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1.
Sci Rep ; 11(1): 17193, 2021 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-34433834

RESUMO

This paper addresses the development of predictive models for distinguishing pre-symptomatic infections from uninfected individuals. Our machine learning experiments are conducted on publicly available challenge studies that collected whole-blood transcriptomics data from individuals infected with HRV, RSV, H1N1, and H3N2. We address the problem of identifying discriminatory biomarkers between controls and eventual shedders in the first 32 h post-infection. Our exploratory analysis shows that the most discriminatory biomarkers exhibit a strong dependence on time over the course of the human response to infection. We visualize the feature sets to provide evidence of the rapid evolution of the gene expression profiles. To quantify this observation, we partition the data in the first 32 h into four equal time windows of 8 h each and identify all discriminatory biomarkers using sparsity-promoting classifiers and Iterated Feature Removal. We then perform a comparative machine learning classification analysis using linear support vector machines, artificial neural networks and Centroid-Encoder. We present a range of experiments on different groupings of the diseases to demonstrate the robustness of the resulting models.


Assuntos
Simulação por Computador , Influenza Humana/virologia , Infecções por Picornaviridae/virologia , Infecções por Vírus Respiratório Sincicial/virologia , Transcriptoma , Eliminação de Partículas Virais , Biomarcadores/metabolismo , Redes Reguladoras de Genes , Humanos , Influenza Humana/genética , Influenza Humana/metabolismo , Aprendizado de Máquina , Orthomyxoviridae/patogenicidade , Orthomyxoviridae/fisiologia , Infecções por Picornaviridae/genética , Infecções por Picornaviridae/metabolismo , Infecções por Vírus Respiratório Sincicial/genética , Infecções por Vírus Respiratório Sincicial/metabolismo , Vírus Sinciciais Respiratórios/patogenicidade , Vírus Sinciciais Respiratórios/fisiologia , Rhinovirus/patogenicidade , Rhinovirus/fisiologia
2.
Mol Biol Rep ; 39(3): 2723-31, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21681430

RESUMO

We have previously shown that angiotensin-converting enzyme (ACE) gene D allele is an independent risk factor for early onset coronary artery disease (CAD). Little is known about the concomitant presence of the ACE gene D allele and paraoxonase (PON1) codon 192 arginine (Arg) on the severity of CAD. Regarding the high rate of CAD among Iranians the aim of present study was to examine the hypothesis of synergistic effects between ACE-D and PON1-Arg alleles on predisposition and the severity of CAD in our population. The PON1 192 and ACE insertion/deletion (I/D) genotypes were detected by PCR-RFLP and PCR, respectively in 414 individuals undergoing their first coronary angiography. Patients were placed into one of two groups: CAD and control without CAD or diabetes. We mentioned the synergistic effects of both genes and not ACE gene alone is a risk factor for CAD. We found that PON1 Arg 192 and ACE D allele act synergistically to increase the risk of CAD (OR 1.3, P = 0.044). Our results showed a significant correlation between the possession of both PON1 192 Arg and the ACE D allele and the extent of CAD in CAD patients and CAD subjects without diabetes, represented by the increased frequency of three-vessel disease with OR 2.7, P = 0.046; χ(2) = 4, P = 0.046 and OR 2.4, P = 0.051; χ(2) = 3.8, P = 0.051, respectively. We found that PON1 Arg 192 and ACE D alleles act synergistically to increase the risk of CAD in CAD patients and CAD subjects without diabetes from west of Iran, who have high frequency of three-vessel disease. Our data suggest that PON1 192 Arg and the ACE D allele in combination with each other can be important independent risk factor for severity of CAD in patients carrying both PON1 192 Arg and the ACE D allele in a west population of Iran.


Assuntos
Arildialquilfosfatase/metabolismo , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/genética , Predisposição Genética para Doença/genética , Peptidil Dipeptidase A/metabolismo , Polimorfismo Genético/genética , Alelos , Arginina/metabolismo , Arildialquilfosfatase/genética , Feminino , Estudos de Associação Genética , Genótipo , Humanos , Mutação INDEL , Irã (Geográfico)/epidemiologia , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Razão de Chances , Peptidil Dipeptidase A/genética , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Fatores de Risco
3.
Environ Technol ; 30(3): 233-9, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19438055

RESUMO

The photocatalytic degradation of Reactive Blue 19 (RB19) dye has been studied using TiO2 nanofibre as the photocatalyst in aqueous solution under UV irradiation. Titanium dioxide nanofibre was prepared using a templating method with tetraisopropylorthotitanate as a precursor. The experiments were carried out in the presence of the TiO2 nanofibre, and the effects of pH and electron acceptors on the degradation process were investigated. In order to observe the quality of the aqueous solution, chemical oxygen demand (COD) measurements were also carried out before and after the treatments. The photocatalytic decomposition of RB19 was most efficient in acidic solution. With the addition of hydrogen peroxide and potassium persulphate, as electron acceptors, into illuminated TiO2 nanofibre suspensions, a synergistic effect was observed leading to an enhancement of the decolorization. From experimental results, under the condition of 1 g TiO2 nanofibre l(-1), pH 3, and UVC light irradiation, decolorization would be complete in two hours. A significant decrease in the COD values was observed, which clearly indicates that the photocatalytic method offers good potential for the removal of RB19 from aqueous solution. The kinetic of photocatalytic removal of RB19 followed the Langmuir-Hinshelwood model. These results suggest that TiO2 nanofibres with UV photocatalysis can be envisaged as a method for the treatment of coloured wastewaters, in particular in textile industries.


Assuntos
Corantes/química , Nanoestruturas/química , Processos Fotoquímicos , Titânio/química , Água/química , Adsorção , Cor , Concentração de Íons de Hidrogênio , Cinética , Nanoestruturas/ultraestrutura , Reprodutibilidade dos Testes , Fatores de Tempo , Raios Ultravioleta , Eliminação de Resíduos Líquidos/métodos
4.
Br J Haematol ; 113(4): 878-85, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11442478

RESUMO

Thromboxane A2 (TXA2), synthesized in platelets, is a powerful aggregating agent and vasoconstrictor. To induce platelet aggregation, the platelets' enzyme, prostaglandin endoperoxide H synthase-1 (PGHS-1), first converts arachidonic acid (AA) into prostaglandin H2 (PGH2). PGH2 is then converted by the enzyme thromboxane synthase into TXA2. Finally, TXA2 is secreted and can activate the TXA2 receptor on the platelet surface. The importance of TXA2 in haemostasis has been demonstrated by the presence of a bleeding tendency in patients showing an inherited defect in the TXA2 production pathway. We studied an 18-year-old woman with a lifelong bleeding disorder, moderate thrombocytopenia (55-71 x 109/l) and a prolonged bleeding time (12.5 min). Her platelets aggregated in the presence of both PGH2 and a stable TXA2 analogue, but did not aggregate in the presence of AA. The activity of PGHS-1 in platelets, measured using thin-layer chromatography and radioactive counting of TXA2 formation from [14C]-AA, was reduced to 13% of the activity measured in control subjects. PGHS-1 protein levels, measured using Western blot analysis, were also markedly reduced to 10% of control values. Such levels of PGHS-1 enzyme were too low to sustain platelet aggregation in the patient, even if the enzyme was active. The PGHS-1 protein level was also reduced in the patient's immortalized B lymphocytes, suggesting a systemic expression defect. Northern blot analysis was then carried out with poly (A)+ RNA extracted from the patient's immortalized B lymphocytes. PGHS-1 mRNA was detected as a 2.8-kb band in both the patient and control. The intensity of the band representing the patient's PGHS-1 mRNA was similar to that of the control subject. The Northern blot result suggests a normal transcriptional rate of the PGHS-1 gene for the patient. Therefore, the defect responsible for the reduced levels of PGHS-1 protein is probably post-transcriptional.


Assuntos
Transtornos da Coagulação Sanguínea/enzimologia , Prostaglandina-Endoperóxido Sintases/deficiência , Adulto , Ácido Araquidônico/metabolismo , Autorradiografia , Linfócitos B/enzimologia , Plaquetas/enzimologia , Northern Blotting , Western Blotting , Estudos de Casos e Controles , Linhagem Celular , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Agregação Plaquetária , Prostaglandina-Endoperóxido Sintases/genética , Prostaglandina-Endoperóxido Sintases/metabolismo , RNA Mensageiro/análise , Tromboxano A2/biossíntese , Tromboxano B2/metabolismo
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