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1.
Polymers (Basel) ; 16(9)2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38732758

RESUMO

Biopolymers are biodegradable and renewable and can significantly reduce environmental impacts. For this reason, biocomposites based on a plasticized starch and cross-linker matrix and with a microfibrillated OCC cardboard cellulose reinforcement were developed. Biocomposites were prepared by suspension casting with varied amounts of microfibrillated cellulose: 0, 4, 8, and 12 wt%. Polyethylene glycol diglycidyl ether (PEGDE) was used as a cross-linking, water-soluble, and non-toxic agent. Microfibrillated cellulose (MFC) from OCC cardboard showed appropriate properties and potential for good performance as a reinforcement. In general, microfiber incorporation and matrix cross-linking increased crystallization, reduced water adsorption, and improved the physical and tensile properties of the plasticized starch. Biocomposites cross-linked with PEGDE and reinforced with 12 wt% MFC showed the best properties. The chemical and structural changes induced by the cross-linking of starch chains and MFC reinforcement were confirmed by FTIR, NMR, and XRD. Biodegradation higher than 80% was achieved for most biocomposites in 15 days of laboratory compost.

2.
Minerva Urol Nephrol ; 75(1): 116-123, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34114785

RESUMO

BACKGROUND: The average accepted depth for non-tunneled catheters (NTC) insertion does not guarantee its correct position, so controversy exists. The aim of this study was to assess the effect of two NTC placement depths on the number of NTC complication episodes. METHODS: We designed a triple blind, parallel group, randomized controlled trial in a single Hemodialysis Center in Mexico (Registry: ACTRN12619000774123). We included patients in urgent need of hemodialysis via internal right jugular vein NTC. The length of the NTC tip placement depth was randomized to second intercostal space (2ICS) or fourth intercostal space (4ICS), using physical landmarks. The primary outcome was to compare the composite number of NTC dysfunction, repositioning, and relocation episodes for 48 hours post-procedure. RESULTS: One hundred and sixty-five patients were included, 86 and 79 patients to NTC placement in the 2ICS and 4ICS, respectively. All patients underwent intention-to-treat analysis. The incidence of the composite outcome was lower in the 2ICS group compared to the 4ICS group, 4 (4.6%) and 50 (63%) combined episodes, respectively (P<0.001). Compared to the 4ICS group, the 2ICS group presented a relative risk of 0.06 (CI: 0.02-0.21, P<0.001) and number needed to treat (NNT) of 2.1. No adverse events occurred, derived from the NTC placement. CONCLUSIONS: NTC tip placement in the 2ICS compared to 4ICS decreases the incidence of the combined number of dysfunctions, repositioning and relocation episodes, with a NNT of 2 for its prevention.


Assuntos
Cateterismo Venoso Central , Cateteres Venosos Centrais , Humanos , Cateterismo Venoso Central/efeitos adversos , Cateterismo Venoso Central/métodos , Diálise Renal/efeitos adversos , Cateteres Venosos Centrais/efeitos adversos , Incidência , México
3.
Rev. invest. clín ; 73(4): 216-221, Jul.-Aug. 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1347567

RESUMO

Background: The impact of donor quality on post-kidney transplant survival may vary by candidate condition. Objective: Analyzing the combined use of the Kidney Donor Profile Index (KDPI) and the estimated post-transplant survival (EPTS) scale and their correlation with the estimated glomerular filtration rate (eGFR) decline in deceased-donor kidney recipients (DDKR). Methods: This was a retrospective, observational cohort study. We included DDKRs between 2015 and 2017 at a national third-level hospital. Results: We analyzed 68 DDKR. The mean age at transplant was 41 ± 14 years, 47 (69%) had sensitization events, 18 (26%) had delayed graft function, and 16 (23%) acute rejection. The graft survival at 12 and 36 months was 98.1% (95% CI 94-100) and 83.7% (95% CI 65-100), respectively. The Pearson correlation coefficient between the percentage reduction in the annual eGFR and the sum of EPTS and KDPI scales was r = 0.61, p < 0.001. The correlation coefficient between the percentage reduction in the annual eGFR and the EPTS and KDPI scales separately was r = 0.55, p < 0.001, and r = 0.53, p < 0.001, respectively. Conclusions: The sum of EPTS and KDPI scales can provide a better donor-recipient relationship and has a moderately positive correlation with the decrease in eGFR in DDKR.


Assuntos
Humanos , Adulto , Pessoa de Meia-Idade , Doadores de Tecidos , Transplante de Rim , Sobrevivência de Enxerto , Análise de Sobrevida , Estudos Retrospectivos , Transplantados , Taxa de Filtração Glomerular , Rim
4.
Rev Invest Clin ; 73(4): 216-221, 2021 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-33758426

RESUMO

BACKGROUND: The impact of donor quality on post-kidney transplant survival may vary by candidate condition. OBJECTIVE: Analyzing the combined use of the Kidney Donor Profile Index (KDPI) and the estimated post-transplant survival (EPTS) scale and their correlation with the estimated glomerular filtration rate (eGFR) decline in deceased-donor kidney recipients (DDKR). METHODS: This was a retrospective, observational cohort study. We included DDKRs between 2015 and 2017 at a national third-level hospital. RESULTS: We analyzed 68 DDKR. The mean age at transplant was 41 ± 14 years, 47 (69%) had sensitization events, 18 (26%) had delayed graft function, and 16 (23%) acute rejection. The graft survival at 12 and 36 months was 98.1% (95% CI 94-100) and 83.7% (95% CI 65-100), respectively. The Pearson correlation coefficient between the percentage reduction in the annual eGFR and the sum of EPTS and KDPI scales was r = 0.61, p < 0.001. The correlation coefficient between the percentage reduction in the annual eGFR and the EPTS and KDPI scales separately was r = 0.55, p < 0.001, and r = 0.53, p < 0.001, respectively. CONCLUSIONS: The sum of EPTS and KDPI scales can provide a better donor-recipient relationship and has a moderately positive correlation with the decrease in eGFR in DDKR.


Assuntos
Sobrevivência de Enxerto , Transplante de Rim , Doadores de Tecidos , Adulto , Taxa de Filtração Glomerular , Humanos , Rim , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de Sobrevida , Transplantados
5.
Medicina (B Aires) ; 79(3): 161-166, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31284249

RESUMO

Rheumatoid arthritis is a clinical autoimmune syndrome that causes joint damage. The positive or negative anti-cyclic citrullinated protein (CCP) antibodies serodiagnosis differentiates two subsets of the disease, each with different genetic background. Previous studies have identified associations between KIR genes and rheumatoid arthritis but not with anti-CCP serodiagnosis. Therefore, we investigated the proportion of patients seropositive and seronegative to anti-CCP and its possible association with KIR (killer cell immunoglobulin-like receptor) genes. We included 100 patients with rheumatoid arthritis from western Mexico, who were determined for anti-CCP serodiagnosis by ELISA, and 16 KIR genes were genotyped by PCR-SSP. The proportion of seropositive anti-CCP patients was 83%, and they presented a higher frequency of KIR2DL2 genes than the seronegative group (73.6% vs. 46.2%, p = 0.044) which, in turn, presented a higher KIR2DL2-/KIR2DL3+ genotype frequency than the first ones (46.2% vs. 17.2%, p = 0.043). These results suggest different KIR genetic backgrounds for each subset of the disease according to anti-CCP serodiagnosis.


La artritis reumatoide es un síndrome clínico autoinmune que causa daño en las articulaciones. El serodiagnóstico positivo o negativo para anticuerpos proteicos anticíclicos citrulinados (CCP) diferencia dos subconjuntos de la enfermedad, cada uno con diferente fondo genético. Estudios previos han identificado asociaciones entre los genes killer cell immunoglobulin- like receptor (KIR) y la artritis reumatoide, pero no con el serodiagnóstico de anti-CCP. Por lo tanto, investigamos la proporción de seropositividad y seronegatividad anti-CCP y su posible asociación con genes KIR. Se incluyeron 100 pacientes con artritis reumatoide del occidente de México, a quienes se les determinó su serodiagnóstico anti-CCP por ELISA y también se les realizó genotipificación de 16 genes KIR por PCR-SSP. La proporción de pacientes seropositivos anti-CCP fue del 83% y presentaron una mayor frecuencia génica KIR2DL2 que el grupo seronegativo (73.6% vs. 46.2%, p = 0.044), estos últimos presentaron mayor frecuencia genotípica KIR2DL2-/KIR2DL3+ que los primeros (46.2% vs. 17.2%, p = 0.043). Los resultados sugieren diferente fondo genético KIR para cada subconjunto de la enfermedad, de acuerdo con el serodiagnóstico anti-CCP.


Assuntos
Artrite Reumatoide/diagnóstico , Autoanticorpos/sangue , Receptores KIR2DL2/genética , Adulto , Idoso , Artrite Reumatoide/sangue , Artrite Reumatoide/genética , Autoanticorpos/genética , Feminino , Genótipo , Humanos , Masculino , México , Pessoa de Meia-Idade , Fator Reumatoide/sangue
6.
Medicina (B.Aires) ; 79(3): 161-166, June 2019. tab
Artigo em Inglês | LILACS | ID: biblio-1020053

RESUMO

Rheumatoid arthritis is a clinical autoimmune syndrome that causes joint damage. The positive or negative anti-cyclic citrullinated protein (CCP) antibodies serodiagnosis differentiates two subsets of the disease, each with different genetic background. Previous studies have identified associations between KIR genes and rheumatoid arthritis but not with anti-CCP serodiagnosis. Therefore, we investigated the proportion of patients seropositive and seronegative to anti-CCP and its possible association with KIR (killer cell immunoglobulin-like receptor) genes. We included 100 patients with rheumatoid arthritis from western Mexico, who were determined for anti-CCP serodiagnosis by ELISA, and 16 KIR genes were genotyped by PCR-SSP. The proportion of seropositive anti-CCP patients was 83%, and they presented a higher frequency of KIR2DL2 genes than the seronegative group (73.6% vs. 46.2%, p = 0.044) which, in turn, presented a higher KIR2DL2-/ KIR2DL3+ genotype frequency than the first ones (46.2% vs. 17.2%, p = 0.043). These results suggest different KIR genetic backgrounds for each subset of the disease according to anti-CCP serodiagnosis.


La artritis reumatoide es un síndrome clínico autoinmune que causa daño en las articulaciones. El serodiagnóstico positivo o negativo para anticuerpos proteicos anti-cíclicos citrulinados (CCP) diferencia dos subconjuntos de la enfermedad, cada uno con diferente fondo genético. Estudios previos han identificado asociaciones entre los genes killer cell immunoglobulin- like receptor (KIR) y la artritis reumatoide, pero no con el serodiagnóstico de anti-CCP. Por lo tanto, investigamos la proporción de seropositividad y seronegatividad anti-CCP y su posible asociación con genes KIR. Se incluyeron 100 pacientes con artritis reumatoide del occidente de México, a quienes se les determinó su serodiagnóstico anti-CCP por ELISA y también se les realizó genotipificación de 16 genes KIR por PCR-SSP. La proporción de pacientes seropositivos anti-CCP fue del 83% y presentaron una mayor frecuencia génica KIR2DL2 que el grupo seronegativo (73.6% vs. 46.2%, p = 0.044), estos últimos presentaron mayor frecuencia genotípica KIR2DL2-/KIR2DL3+ que los primeros (46.2% vs. 17.2%, p = 0.043). Los resultados sugieren diferente fondo genético KIR para cada subconjunto de la enfermedad, de acuerdo con el serodiagnóstico anti-CCP.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Artrite Reumatoide/diagnóstico , Autoanticorpos/sangue , Receptores KIR2DL2/genética , Artrite Reumatoide/genética , Artrite Reumatoide/sangue , Fator Reumatoide/sangue , Autoanticorpos/genética , Genótipo , México
7.
J Magn Reson Imaging ; 46(2): 557-564, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-27869333

RESUMO

PURPOSE: To improve the conspicuity of white matter lesions (WMLs) in multiple sclerosis (MS) using patient-specific optimization of single-slab 3D fluid-attenuated inversion recovery (FLAIR) magnetic resonance imaging (MRI). MATERIALS AND METHODS: Sixteen MS patients were enrolled in a prospective 3.0T MRI study. FLAIR inversion time and echo time were automatically optimized for each patient during the same scan session based on measurements of the relative proton density and relaxation times of the brain tissues. The optimization criterion was to maximize the contrast between gray matter (GM) and white matter (WM), while suppressing cerebrospinal fluid. This criterion also helps increase the contrast between WMLs and WM. The performance of the patient-specific 3D FLAIR protocol relative to the fixed-parameter protocol was assessed both qualitatively and quantitatively. RESULTS: Patient-specific optimization achieved a statistically significant 41% increase in the GM-WM contrast ratio (P < 0.05) and 32% increase in the WML-WM contrast ratio (P < 0.01) compared with fixed-parameter FLAIR. The increase in WML-WM contrast ratio correlated strongly with echo time (P < 10-11 ). Two experienced neuroradiologists indicated substantially higher lesion conspicuity on the patient-specific FLAIR images over conventional FLAIR in 3-4 cases (intrarater correlation coefficient ICC = 0.72). In no case was the image quality of patient-specific FLAIR considered inferior to conventional FLAIR by any of the raters (ICC = 0.32). CONCLUSION: Changes in proton density and relaxation times render fixed-parameter FLAIR suboptimal in terms of lesion contrast. Patient-specific optimization of 3D FLAIR increases lesion conspicuity without scan time penalty, and has potential to enhance the detection of subtle and small lesions in MS. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 1 J. MAGN. RESON. IMAGING 2017;46:557-564.


Assuntos
Imageamento Tridimensional , Imageamento por Ressonância Magnética , Esclerose Múltipla/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Adulto , Encéfalo/diagnóstico por imagem , Líquido Cefalorraquidiano , Meios de Contraste/química , Feminino , Substância Cinzenta/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes
8.
J Hum Genet ; 55(10): 697-700, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20668460

RESUMO

Coding variants in both myocilin (MYOC) and optineurin (OPTN) are reported risk factors for primary open-angle glaucoma (POAG) in many populations. This study investigated the contribution of MYOC and OPTN coding variants in Hispanics of Mexican descent with and without POAG. We conducted a case-control study of unrelated POAG cases and nonglaucomatous controls in a population of Hispanics of Mexican descent. Ascertainment criteria for POAG included the presence of glaucomatous optic neuropathy with associated visual field loss and the absence of secondary causes of glaucoma. Controls had normal optic nerves, visual fields and intraocular pressure. All coding exons of MYOC and OPTN were sequenced. The data set consisted of 88 POAG cases and 93 controls. A novel nonsynonymous coding variant (R7H) in the first exon of MYOC was identified. Other identified variants in MYOC and OPTN have been previously described and do not seem to contribute to POAG risk. This is the first comprehensive study of MYOC and OPTN in Hispanics of Mexican descent with POAG. Neither MYOC nor OPTN sequence variants seem to have a major role in the etiology of POAG in this population.


Assuntos
Proteínas do Citoesqueleto/genética , Proteínas do Olho/genética , Variação Genética , Glaucoma de Ângulo Aberto/genética , Glicoproteínas/genética , Hispânico ou Latino/genética , Americanos Mexicanos/estatística & dados numéricos , Fator de Transcrição TFIIIA/genética , Estudos de Casos e Controles , Proteínas de Ciclo Celular , Feminino , Humanos , Masculino , Proteínas de Membrana Transportadoras , México/etnologia
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