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1.
Public Health ; 225: 1-7, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37913609

RESUMO

OBJECTIVE: We estimated the impact of the changes made to the Public Charge Rule on the initiation of prenatal care among uninsured immigrants in the United States. STUDY DESIGN: We used a difference-in-differences approach to analyse the impact of the changes made to the Public Charge Rule (first difference) on initiation of prenatal care between uninsured and privately insured immigrants (second difference). METHODS: We used the natality data by the National Center for Health Statistics as the main data source, which includes all singleton births in a hospital to an immigrant birthing person aged from 15 to 44. The study covers three phases: (1) the period prior to the leaked draft Executive Orders concerning changes made to the public charge policy-from January 2014 to December 2016; (2) the period after the draft Executive Orders were leaked until the proposal of the Public Charge Rule-from January 2017 to September 2018; and (3) post proposal of the Public Charge Rule -from October 2018 to December 2019. RESULTS: After the proposal of the Public Charge Rule in 2018, the odds of initiating prenatal care in the first trimester decreased among uninsured immigrants by 12% (odds ratio [OR]: 0.880; 95% confidence interval [CI]: 0.832, 0.931) compared to privately insured immigrants. The odds of second trimester initiation of prenatal care was also negatively associated with the leak of the draft Executive Orders (OR: 0.942; 95% CI: 0.905, 0.981). CONCLUSION: The results of this study suggest that uninsured immigrants in the United States significantly delayed prenatal care after the changes were made to the Public Charge Rule.


Assuntos
Emigrantes e Imigrantes , Pessoas sem Cobertura de Seguro de Saúde , Gravidez , Feminino , Humanos , Estados Unidos , Cuidado Pré-Natal , Seguro Saúde , Política Pública
2.
Med Biol Eng Comput ; 61(1): 155-177, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36342598

RESUMO

Combining two medical images from different modalities is more helpful for using the resulting image in the healthcare field. Medical image fusion means combining two or more images coming from multiple sensors. This technology obtains an output image that presents more effective and useful information from two images. This paper proposes a multi-modal medical image fusion algorithm based on the nonsubsampled contourlet transform (NSCT) and pulse coupled neural networks (PCNN) methods. The input images are decomposed using the NSCT method into low- and high-frequency subbands. The PCNN is a fusion rule for integrating both low- and high-frequency subbands. The inverse of the NSCT method is to reconstruct the fused image. The results of medical image fusion help doctors with disease diagnosis and patient treatment. The proposed algorithm is tested on six groups of multi-modal medical images using 100 pairs of input images. The proposed algorithm is compared with eight fusion methods. We evaluate the performance of the proposed algorithm using the fusion metrics: peak signal to noise ratio (PSNR), mutual information (MI), entropy (EN), weighted edge information (Q[Formula: see text]), nonlinear correlation information entropy (Q[Formula: see text]), standard deviation (SD), and average gradient (AG). Experimental results show that the proposed algorithm can perform better than other medical image fusion methods and achieve promising results.


Assuntos
Algoritmos , Redes Neurais de Computação , Humanos , Razão Sinal-Ruído , Entropia , Benchmarking , Processamento de Imagem Assistida por Computador/métodos
3.
BioData Min ; 15(1): 24, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36175944

RESUMO

BACKGROUND: Machine learning can be used to predict the different onset of human cancers. Highly dimensional data have enormous, complicated problems. One of these is an excessive number of genes plus over-fitting, fitting time, and classification accuracy. Recursive Feature Elimination (RFE) is a wrapper method for selecting the best subset of features that cause the best accuracy. Despite the high performance of RFE, time computation and over-fitting are two disadvantages of this algorithm. Random forest for selection (RFS) proves its effectiveness in selecting the effective features and improving the over-fitting problem. METHOD: This paper proposed a method, namely, positions first bootstrap step (PFBS) random forest selection recursive feature elimination (RFS-RFE) and its abbreviation is PFBS- RFS-RFE to enhance cancer classification performance. It used a bootstrap with many positions included in the outer first bootstrap step (OFBS), inner first bootstrap step (IFBS), and outer/ inner first bootstrap step (O/IFBS). In the first position, OFBS is applied as a resampling method (bootstrap) with replacement before selection step. The RFS is applied with bootstrap = false i.e., the whole datasets are used to build each tree. The importance features are hybrid with RFE to select the most relevant subset of features. In the second position, IFBS is applied as a resampling method (bootstrap) with replacement during applied RFS. The importance features are hybrid with RFE. In the third position, O/IFBS is applied as a hybrid of first and second positions. RFE used logistic regression (LR) as an estimator. The proposed methods are incorporated with four classifiers to solve the feature selection problems and modify the performance of RFE, in which five datasets with different size are used to assess the performance of the PFBS-RFS-RFE. RESULTS: The results showed that the O/IFBS-RFS-RFE achieved the best performance compared with previous work and enhanced the accuracy, variance and ROC area for RNA gene and dermatology erythemato-squamous diseases datasets to become 99.994%, 0.0000004, 1.000 and 100.000%, 0.0 and 1.000, respectively. CONCLUSION: High dimensional datasets and RFE algorithm face many troubles in cancers classification performance. PFBS-RFS-RFE is proposed to fix these troubles with different positions. The importance features which extracted from RFS are used with RFE to obtain the effective features.

4.
ACS Appl Mater Interfaces ; 14(5): 6894-6905, 2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35099176

RESUMO

All-inorganic perovskite solar cells (IPSCs) have gained massive attention due to their less instability against common degradation factors (light, heat, and moisture) than their organic-inorganic hybrid counterparts. Inorganic perovskites bear a general formula of CsPbX3 (X = Cl, I, Br). The mixed halide CsPbIBr2 perovskite possesses an intermediate band gap of 2.03 eV with enhanced stability, which is still available for photovoltaic applications and the research focus of this work. We present a synergistic approach of pre-heated solution dropping with inorganic additive inclusion to deposit the organic-free triple anion CsPbIBr2 PSC. Erbium (Er)-passivated triple-anion CsI(PbBr2)0.97(ErCl3)0.03 IPSCs with inorganic carrier selective layers (CTLs), that is, organic-free, are fabricated with enhanced carrier diffusion length and crystalline grain size while lessening the grain boundaries near perovskite active layer (PAL)-bulk/carrier selective interfaces. As a result, the trap-state densities within the perovskite bulk were suppressed with stabilized CTL/PAL interfaces for smooth and enhanced carrier transportation. Therefore, for the first time, we contradict the common belief of VOC loss due to halide segregation, as a nice VOC of about 1.34 V is achieved for an organic-free IPSC through enriching initial radiative efficiency, even when halide segregation is present. The optimized organic-free IPSC yielded a power conversion efficiency of 11.61% and a stabilized power output of 10.72%, which provides the potential opportunity to integrate into agrivoltaics (AgV) projects.

5.
Opt Quantum Electron ; 53(6): 343, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34188354

RESUMO

Pristine thermally evaporated nickel-(II)-tetraphenyl-21H,23H-porphyrin (NiTPP) thin films are amorphous, but after 4 and 8 h of UV illumination, the films become crystalline with preferred orientations of (112), (103) and (004) and crystallite sizes of (13, 18, 16) and (42, 31, 38) nm after 4 and 8 h, respectively. After UV illumination for 4 and 8 h, the NiTPP thin films are characterized by blueshifted absorption coefficients, increasing the optical and fundamental gap values and decreasing the dispersion parameter values. The dielectric properties display energy storage regions corresponding to the peak values of optical conductivity, which provides an elegant confirmation of the tailoring and tuning of band gaps, energy storage properties and optical conductivity by UV illumination time. Therefore, NiTPP films may be good candidates for environmental and energy storage applications.

6.
Int J Environ Sci Technol (Tehran) ; 18(2): 393-400, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32837522

RESUMO

Characterization of organic nickel-(II)-tetraphenyl-21H,23H-porphyrin films as a function of substrate type was performed for energy storage applications and consequently environmental enhancement. Nickel-(II)-tetraphenyl-21H,23H-porphyrin films show an amorphous phase. They have a crystallite size of 8-11 nm. Strain caused a shift of different humps' positions. The measured transmittance has high values within the range of 85-91%, and the absorption coefficient values were included within the high-absorption region. Both optical gap and fundamental gap, refractive index, carrier-concentration-to-effective-mass ratio and lattice dielectric constant were calculated, and they were found to be increased, except refractive index and lattice dielectric constant. The obtained data indicated that nickel-(II)-tetraphenyl-21H,23H-porphyrin films are a candidate for energy storage applications.

7.
Neuroimage ; 189: 288-306, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30611874

RESUMO

Diffusion MRI-based probabilistic tractography is a powerful tool for non-invasively investigating normal brain architecture and alterations in structural connectivity associated with disease states. Both voxelwise and region-of-interest methods of analysis are capable of integrating population differences in tract amplitude (streamline count or density), given proper alignment of the tracts of interest. However, quantification of tract differences (between groups, or longitudinally within individuals) has been hampered by two related features of white matter. First, it is unknown to what extent healthy individuals differ in the precise location of white matter tracts, and to what extent experimental factors influence perceived tract location. Second, white matter lacks the gross neuroanatomical features (e.g., gyri, histological subtyping) that make parcellation of grey matter plausible - determining where tracts "should" lie within larger white matter structures is difficult. Accurately quantifying tractographic connectivity between individuals is thus inherently linked to the difficulty of identifying and aligning precise tract location. Tractography is often utilized to study neurological diseases in which the precise structural and connectivity abnormalities are unknown, underscoring the importance of accounting for individual differences in tract location when evaluating the strength of structural connectivity. We set out to quantify spatial variance in tracts aligned through a standard, whole-brain registration method, and to assess the impact of location mismatch on groupwise assessments of tract amplitude. We then developed a method for tract alignment that enhances the existing standard whole brain registration, and then tested whether this method improved the reliability of groupwise contrasts. Specifically, we conducted seed-based probabilistic diffusion tractography from primary motor, supplementary motor, and visual cortices, projecting through the corpus callosum. Streamline counts decreased rapidly with movement from the tract center (-35% per millimeter); tract misalignment of a few millimeters caused substantial compromise of amplitude comparisons. Alignment of tracts "peak-to-peak" is essential for accurate amplitude comparisons. However, for all transcallosal tracts registered through the whole-brain method, the mean separation distance between an individual subject's tract and the average tract (3.2 mm) precluded accurate comparison: at this separation, tract amplitudes were reduced by 74% from peak value. In contrast, alignment of subcortical tracts (thalamo-putaminal, pallido-rubral) was substantially better than alignment for cortical tracts; whole-brain registration was sufficient for these subcortical tracts. We demonstrated that location mismatches in cortical tractography were sufficient to produce false positive and false negative amplitude estimates in both groupwise and longitudinal comparisons. We then showed that our new tract alignment method substantially reduced location mismatch and improved both reliability and statistical power of subsequent quantitative comparisons.


Assuntos
Córtex Cerebral/diagnóstico por imagem , Corpo Caloso/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Processamento de Imagem Assistida por Computador/métodos , Substância Branca/diagnóstico por imagem , Adolescente , Adulto , Idoso , Imagem de Tensor de Difusão/normas , Feminino , Humanos , Processamento de Imagem Assistida por Computador/normas , Masculino , Pessoa de Meia-Idade , Probabilidade , Adulto Jovem
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 205: 364-375, 2018 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-30036804

RESUMO

In the present paper, a novel dye of 4-methyl-5-(4-acetylphenyldiazenyl)thiazol-2-amine (L) and its corresponding copper complexes are synthesized and characterized using different techniques including elemental analysis, thermal analysis, 1H NMR, Mass, and FT-IR spectra. The thermal behavior of L and its complexes is carried out and discussed using thermogravimetric analysis, and it observed that the type of copper substituent affects the thermal decomposition of complexes. Homogenous thin films of L and its complexes are successfully grown onto quartz substrates using spin coating technique. Optical features and spectral phenomena of the thin films are studied using spectrophotometric measurements of absorbance, transmittance and reflectance. The optical constants such as refractive index, extinction coefficient, optical conductivity and energy loss functions of the thin films of L and its complexes are calculated. The refractive index curves for all films show a normal dispersion behavior in the non-absorbing region of spectra, from which the dispersion parameters can be calculated using Wemple-DiDomenico model. The type of optical transition bands shows indirect allowed. The values of the optical energy gap are calculated in the range from 2.13 to 2.33 eV, depending on the nature of Cu(II) substituent. Indeed, the present results show that the complexes as organic semiconductors acquired good characterizations better than metal free ligand (L) such as more thermal stability, reducing in the optical band gap and increasing in the absorption coefficient that refers to light harvesting capacity.

9.
Aliment Pharmacol Ther ; 45(5): 681-687, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28070899

RESUMO

BACKGROUND: Chronic hepatitis C virus infection is one of the most important health problems in Egypt. The Ministry of Health's National Treatment Programme introduced sofosbuvir-based therapy in October 2014. AIM: To assess the clinical effectiveness and predictors of response to SOF-based treatment regimens, either dual therapy, with SOF/ribavirin (RBV) for 6 months or triple therapy with SOF/peg-IFN-alfa-2a/RBV for 3 months, in a cohort of patients treated in National Treatment Programme affiliated centres in Egypt. METHODS: Between October 2014 and end of 2014, patients who were eligible for treatment were classified according to their eligibility for interferon therapy: Group 1 (interferon eligible) were treated with triple therapy for 12 weeks and Group 2 (interferon ineligible) were treated with dual therapy for 24 weeks. Difficult to treat patients included those with F3-F4 on Metavir score, Fib-4 >3.25, albumin ≤3.5, total Bilirubin >1.2 mg/dL, INR >1.2 and platelet count <150 000 mm3 . RESULTS: Twelve weeks post-treatment data were available on 14 409 patients; 8742 in group 1 and 5667 in group 2. In group 1, the sustained virological response at week 12 (SVR12) was 94% and in group 2 the SVR12 was 78.7%. Multivariate logistic regression analysis in which treatment failure is the dependent variable was done. Male gender, being a difficult to treat patient and previous interferon therapy were significant predictors of nonresponse in both treatment groups. CONCLUSION: Results of sofosbuvir-based therapies in Egypt achieved similar rates of SVR12 as seen in phase III efficacy studies.


Assuntos
Antivirais/administração & dosagem , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Sofosbuvir/administração & dosagem , Adulto , Antivirais/uso terapêutico , Quimioterapia Combinada , Egito , Feminino , Genótipo , Humanos , Interferon-alfa/administração & dosagem , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/administração & dosagem , Proteínas Recombinantes/administração & dosagem , Estudos Retrospectivos , Ribavirina/administração & dosagem , Ribavirina/uso terapêutico
11.
Clin Obes ; 5(6): 333-41, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26434773

RESUMO

The objective of this study was to evaluate health outcomes and costs of pregnancies complicated by extreme maternal obesity (class III obesity, body mass index ≥ 40). We conducted a retrospective case-control descriptive study comparing extremely obese women (cases) and their infants with randomly selected controls. Health outcomes were obtained from the medical records and costs from billing data. Total costs for each mother-infant dyad were calculated. Compared with 85 controls, the 82 cases experienced higher morbidity, higher costs and prolonged hospital stay. However, 26% of cases maintained or lost weight during pregnancy, whereas none of the controls maintained or lost weight during pregnancy. When mother/infant dyads were compared on costs, case subjects who maintained or lost weight experienced lower costs than those who gained weight. Neonatal intensive care consumed 78% of total hospital costs for infants of the obese women who gained weight, but only 48% of costs for infants of obese women who maintained or lost weight. For extremely obese women, weight management during pregnancy was achievable, resulted in healthier neonatal outcomes and reduced perinatal healthcare costs.


Assuntos
Custos Hospitalares , Mães , Obesidade Mórbida/economia , Obesidade Mórbida/terapia , Complicações na Gravidez/economia , Complicações na Gravidez/terapia , Adulto , Índice de Massa Corporal , Feminino , Humanos , Recém-Nascido , Terapia Intensiva Neonatal/economia , Tempo de Internação , Obesidade Mórbida/complicações , Gravidez , Resultado da Gravidez , Estudos Retrospectivos , Estados Unidos , Aumento de Peso , Redução de Peso
12.
Spectrochim Acta A Mol Biomol Spectrosc ; 148: 338-47, 2015 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-25911158

RESUMO

In this work, we report on the effect of γ-ray irradiation and annealing temperature on the optical properties of metal-free tetraphenylporphyrin, H2TPP, and zinc tetraphenylporphyrin, ZnTPP, thin films. Thin films of H2TPP and ZnTPP were successfully prepared by the thermal evaporation technique. The optical properties of H2TPP and ZnTPP films were investigated using spectrophotometric measurements of the transmittance and reflectance at normal incidence of light in the wavelength range from 200 to 2500 nm. The absorption spectra of H2TPP showed four absorption bands, namely the Q, B, N and M bands. The effect of inserting Zn atom into the cavity of porphyrin macrocycle in ZnTPP molecule distorted the Q and B bands, reduced the width of absorption region and influenced the optical constants and dispersion parameters. In all conditions, the type of electron transition is indirect allowed transition. Anomalous dispersion is observed in the absorption region but normal dispersion occurs in the transparent region of spectra. We adopted multi-oscillator model and the single oscillator model to interpret the anomalous and normal dispersion, respectively. We have found that the annealing temperature has mostly the opposite effect of γ-ray irradiation on absorption and dispersion characteristics of these films.

13.
Ophthalmic Res ; 49(4): 177-84, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23306536

RESUMO

To evaluate a possible association between the complement factor H (CFH) Y402H polymorphism and susceptibility to age-related macular degeneration (AMD) in the Tunisian population, as well as the impact of the genotype distribution among different phenotypes and the response to treatment with intravitreal bevacizumab, exon 9 of CFH was analyzed for the Y402H polymorphism by direct sequencing in 135 healthy controls and 127 sporadic unrelated AMD patients classified into the following groups: 12 atrophic AMD (group G1), 115 exudative AMD (G2) and 10 AMD patients who had fibrovascular scarring (G3) that did not allow a precise grading of the phenotype. Seventy patients in G2 were treated with 1.25 mg intravitreal bevacizumab at 6-week intervals until choroidal neovascularization (CNV) was no longer active. The frequency of the CFH 402H allele was significantly higher in AMD patients than in controls (p = 2.62 × 10(-16)). However, subgroup analysis does not reveal any association between the variant allele H and phenotypes of AMD or CNV. Also, there was no significant difference in response to bevacizumab treatment according to Y402H CFH genotype (p = 0.59). A strong association of the 402H allele with susceptibility to AMD in the Tunisian population was confirmed; however, this variant does not appear to be involved in the clinical progression of this disease or in the postintravitreal bevacizumab response.


Assuntos
Degeneração Macular/genética , Polimorfismo de Nucleotídeo Único , Idoso , Idoso de 80 Anos ou mais , Inibidores da Angiogênese/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Bevacizumab , Estudos de Casos e Controles , Fator H do Complemento/genética , Feminino , Angiofluoresceinografia , Frequência do Gene , Genótipo , Humanos , Injeções Intravítreas , Degeneração Macular/diagnóstico , Degeneração Macular/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Tunísia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Acuidade Visual/fisiologia
15.
Transplant Proc ; 43(2): 433-6, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21440726

RESUMO

As chemokines and adhesion molecules play major roles in the process by which leukocytes are recruited from the bloodstream into sites of inflammation, genetic variations in the production or activity of molecules may influence susceptibility to acute rejection episodes. This study sought to determine the impact of recipient monocyte chemoattractant protein-1 (MCP-1), chemokine receptor (CCR2, CCR5), and adhesion molecule (ICAM-1, PECAM-1 and L/E selectin) polymorphisms on acute rejection after renal transplantation. We selected 169 healthy blood donors and 173 renal transplant recipients for analysis according to the presence or absence of graft rejection in the first 30 days after transplantation. Using molecular methods DNA was genotyped for 11 polymorphisms of these inflammatory molecules genes. Results were stratified by the incidence of rejection episodes and by human leukocyte antigen (HLA) mismatching. No association was detected between adhesion molecule polymorphisms and the incidence of acute rejection episodes. However, a significant risk of acute renal loss was observed among HLA-identical recipients who possessed the CCR2-64I allele (odds ratio 0.24, 95% confidence interval, 0.05 to 1.06; P=.035). In conclusion, the observed association of CCR2-64I with acute rejection episodes should be added to the spectrum of immunogenetic factors known to be involved in renal allograft rejection.


Assuntos
Quimiocinas/metabolismo , Transplante de Rim/métodos , Polimorfismo Genético , Receptores CCR2/genética , Adulto , Alelos , Doadores de Sangue , Feminino , Rejeição de Enxerto , Antígenos HLA/metabolismo , Humanos , Inflamação , Falência Renal Crônica/genética , Falência Renal Crônica/terapia , Masculino , Tunísia
16.
Saudi J Kidney Dis Transpl ; 22(1): 18-23, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21196609

RESUMO

Chemokines play a major role in the process by which leukocytes are recruited from the bloodstream into the sites of inflammation. Genes for the chemokine receptors CCR5, CCR2 and MCP-1 are characterized by functional polymorphisms implicated in transplant rejection. To investigate this association, we analyzed polymorphisms of CCR5-∆32, CCR5-59029-A/G, CCR2-V64I and MCP-1 G/A (-2518) in 173 renal transplant recipients and 169 healthy blood donors. The patients were classified in two groups: Group-1 (G-1) included 33 HLA-identical recipients and Group-2 (G-2) included 140 (one or more) mismatched graft recipients. Forty-two patients had developed acute rejection episodes (ARs): seven in G-1 and 35 in G-2. Thirteen G-2 patients developed chronic allograft dysfunction (CAD). The genotypic and allelic frequencies of all polymorphisms studied did not reveal significant differences between patients and controls and among G-1 and G-2 recipients. However, a significant risk of acute renal transplant rejection was found in G-1 patients who possessed the CCR2-64I allele (odds ratio 0.24, 95% confidence inter-val [CI], 0.05-1.06; P = 0.035). There was no significant association of this polymorphism and CAD. In conclusion, the observed association of CCR2-64I with AR should be added to the spectrum of immunogenetic factors known to be involved in allograft renal loss.


Assuntos
Quimiocinas/genética , Rejeição de Enxerto/genética , Transplante de Rim/imunologia , Polimorfismo Genético , Doença Aguda , Adulto , Estudos de Casos e Controles , Quimiocina CCL2/genética , Doença Crônica , Feminino , Frequência do Gene , Predisposição Genética para Doença , Rejeição de Enxerto/imunologia , Humanos , Masculino , Razão de Chances , Fenótipo , Receptores CCR2/genética , Receptores CCR5/genética , Medição de Risco , Fatores de Risco , Transplante Homólogo , Resultado do Tratamento , Tunísia , Adulto Jovem
17.
Arch Inst Pasteur Tunis ; 88(1-4): 47-58, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-23461143

RESUMO

Crohn's disease (CD) and ulcerative colitis (UC) have complex genetic background that is characterised by more than one susceptibility locus. To detect a possible association between the functional polymorphisms of the chemokine receptors CCR5, CCR2 and MCP-1 genes and susceptibility to CD and UC in Tunisian population, polymorphisms of CCR5-delta32, CCR5-59029-A/G, CCR2-V641 and MCP-1-2518-G/A were analysed in 194 Inflammatory bowel disease (IBD) patients and 169 healthy blood donors using PCR-RFLP and PCR-SSP methods. The patients were classified in 126 patients with CD and 68 patients with UC. The genotypic and allelic frequencies of all polymorphisms studied, did not reveal significant differences between patients and conrols and among CD and UC patients. However, analysis of CD patients revealed that those without homozygosous G/G genotype are more frequently in remission compared to those with this genotype (OR: 0.4, 95% CI: [0.174-0.928]; p = 0.03). Also, the frequency of the CCR2-641 muted allele was statistically higher in CD patients in remission disease than those in active form (OR: 0.267 95% CI: [0.09-0.78]; p = 0.01). Adjustment for known covariates factors (age, gender and immunosuppressive regimen) confirmed these univariate findings and revealed that the CCR5-59029-A/G and CCR2-V64I genotype were associated to remission form of CD (OR: 263; 95% CI: [1.01-6.80]; p = 0.047 and OR: 4.64; 95% CI: [1.01-21.31]; p = 0.049 respectively). In conclusion, the present study supports the involvement of chemokine receptor (CCR2 and CCR5) polymorphisms in activity degree of the IBD disease in Tunisian patients.


Assuntos
Quimiocinas/genética , Doenças Inflamatórias Intestinais/genética , Polimorfismo Genético , Receptores de Quimiocinas/genética , Adulto , Feminino , Humanos , Masculino , Tunísia
18.
Transplant Proc ; 42(10): 4314-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21168689

RESUMO

Allograft rejection is an immune response relying on the proliferation and the differentiation of T cells. CTLA-4 is a co-stimulatory molecule, expressed on activated T lymphocytes, which has been shown to play a crucial role in the down-regulation of T-cell activation. Herein, we have examined the impart of a genetic marker in the CTLA-4 gene on renal transplant outcomes. A cohort of 144 renal recipients and 100 healthy subjects were genotyped by the fragments analysis method using an automated sequencer. Patients were classified into two groups: Group I included 31 HLA-identical haplotype allograft recipients and Group II, 113 showing one or more HLA haplotype mismatches. Forty patients (27.78%) developed at least one acute rejection episode (ARE): 9 in Group I and 31 in Group II. Before transplantation, 20 patients were lymphocytotoxic antibodies (LCT) positive: 4 Group I, 2 of whom developed an ARE, and sixty in Group II, including 8 with an ARE. The occurrence of an ARE was associated with the presence of LCT before transplantation among the entire cohort of patients (P = .032) and among Group II (P = .037). The allelic frequencies of (AT)n polymorphism did not reveal significant differences between patients and controls. The most prevalent alleles were the 88 bp (51% in controls and 44.44% in patients) and the 106 bp (8% and 10.76%, respectively). We noticed an increase of the 120 bp allele frequency among patients who had undergone an ARE compared with those who did not display this complication (8.75% vs 3.85%). Likewise, among LCT-negative Group I, recipients the incidence of the 120 bp allele was higher in ARE than non-ARE patients. Although the differences were not statistically significant, we propose that the 120 bp allele of the CTLA-4 gene (AT)n microsatellite a predisposes to acute rejection episodes in renal transplantation.


Assuntos
Regiões 3' não Traduzidas , Antígenos CD/genética , Rejeição de Enxerto/genética , Transplante de Rim , Sequências Repetitivas de Ácido Nucleico , Adulto , Alelos , Antígeno CTLA-4 , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Haplótipos , Humanos , Masculino , Polimorfismo Genético , Transplante Homólogo , Tunísia
19.
Arch Inst Pasteur Tunis ; 87(1-2): 53-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21598828

RESUMO

This study aimed to investigate HLA-DRB1 alleles in rheumatoid arthritis (RA) patients from Tunisia and to examine the effect of these alleles on disease severity. HLA-DRBI alleles and sub-typing of DRBI*04 and *01 were determined in 90 patients and 100 healthy controls, by PCR-SSP. HLA-DRB1*04 was significantly higher in patients (51.1%) than in controls (27%) [OR=2.83, p=0.00066]. DRBJ*0405 was found to be the unique DR4 allele associated with RA (28.88% vs 6%) [OR=6.36, p=0.000059]. A significant decrease in the frequency of HLA-DRB1*0701 was observed in RA patients (16.66%) compared to controls (36%) [p=0.0026]. However, the frequency of patients carrying the shared epitope (SE) QRRAA, was slightly increased compared with controls (37.8% vs 23%) [OR=2.03, p=0.039]. We found that the presence of rheumatoid factor, HLA-DR4 and HLA-DRBI*0405 were not significantly associated with bone erosions or the presence of extra-joint involvement. In our population, the SE (QRRAA) expressed in DRBI*04 alleles is related to the susceptibility to RA but it is not involved in RA severity in Tunisia, while DRBI*0701 might protect against this disease.


Assuntos
Artrite Reumatoide/genética , Antígenos HLA-DR/genética , Adulto , Alelos , Sequência de Aminoácidos , Feminino , Cadeias HLA-DRB1 , Humanos , Masculino , Tunísia
20.
Transplant Proc ; 41(8): 3305-7, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19857736

RESUMO

CTLA-4 and CD28 are T lymphocyte receptors involved in the regulation of T-cell activation. Allograft rejection is an alloimune response which is strongly dependent on T-cell proliferation. Thus, we examined the relationship between CTLA-4 and CD28 gene polymorphisms and renal transplant outcomes. We genotyped 141 renal recipients and 229 healthy controls using PCR-SSP methods for the (-318) C/T polymorphism in the promoter region of the CTLA-4 gene and IVS3 (+17) T/C on intron 3 of the CD28 gene, and by PCR-RFLP method for exon 1 (+49) A/G and CT60 G/A within the 3'-untranslated region (UTR) of the CTLA-4 gene. Patients were classified into two groups: Group I included 23 HLA-identical haplotype allograft recipients and group II, 118 recipients with one or more mismatches in HLA haplotypes. Thirty-six patients developed at least one acute rejection episode (ARE). No significant differences were observed between the genotypes or the allele distribution between ARE and non-ARE patients. However, in group I, (+49) A and CT60 (G) allele frequencies were lower in patients with ARE than those without ARE (0.100 and 0.400 vs 0.361 and 0.722 respectively). However, the difference was not significant. Our study suggested that these alleles may confer protection against renal allograft loss.


Assuntos
Antígenos CD/genética , Antígenos CD28/genética , Rejeição de Enxerto/genética , Transplante de Rim/fisiologia , Polimorfismo Genético , Polimorfismo de Nucleotídeo Único , Regiões 3' não Traduzidas/genética , Doença Aguda , Adulto , Substituição de Aminoácidos , Antígeno CTLA-4 , Éxons , Feminino , Genótipo , Rejeição de Enxerto/epidemiologia , Rejeição de Enxerto/imunologia , Antígenos HLA/genética , Humanos , Transplante de Rim/imunologia , Masculino , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples/genética
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