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1.
Biomater Sci ; 12(8): 2108-2120, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38450552

RESUMEN

The antioxidant capabilities of nanoparticles are contingent upon various factors, including their shape, size, and chemical composition. Herein, novel Nd-doped CeO2 nanoparticles were synthesized and the neodymium content was varied to investigate the synergistic impact on the antioxidant properties of CeO2 nanoparticles. Incorporating Nd3+ induced changes in lattice parameters and significantly altered the morphology from nanoparticles to nanorods. The biological activity of Nd-doped CeO2 was examined against pathogenic bacterial strains, breast cancer cell lines, and antioxidant models. The antibacterial and anticancer activities of nanoparticles were not observed, which could be associated with the Ce3+/Ce4+ ratio. Notably, the incorporation of neodymium improved the antioxidant capacity of CeO2. Machine learning techniques were employed to forecast the antioxidant activity to enhance understanding and predictive capabilities. Among these models, the random forest model exhibited the highest accuracy at 96.35%, establishing it as a robust computational tool for elucidating the biological behavior of Nd-doped CeO2 nanoparticles. This study presents the first exploration of the influence of Nd3+ on the structural, optical, and biological attributes of CeO2, contributing valuable insights and extending the application of machine learning in predicting the therapeutic efficacy of inorganic nanomaterials.


Asunto(s)
Nanopartículas , Nanoestructuras , Antioxidantes/farmacología , Antioxidantes/química , Neodimio , Nanopartículas/química , Antibacterianos/farmacología , Antibacterianos/química
2.
Antibiotics (Basel) ; 13(3)2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38534655

RESUMEN

The rise in antibiotic-resistant bacteria is a global health challenge. Due to their unique properties, metal oxide nanoparticles show promise in addressing this issue. However, optimizing these properties requires a deep understanding of complex interactions. This study incorporated data-driven machine learning to predict bacterial survival against lanthanum-doped ZnO nanoparticles. The effect of incorporation of lanthanum ions on ZnO was analyzed. Even with high lanthanum concentration, no significant variations in structural, morphological, and optical properties were observed. The antibacterial activity of La-doped ZnO nanoparticles against Gram-positive and Gram-negative bacteria was qualitatively and quantitatively evaluated. Nanoparticles induce 60%, 95%, and 55% bacterial death against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus, respectively. Algorithms such as Multilayer Perceptron, K-Nearest Neighbors, Gradient Boosting, and Extremely Random Trees were used to predict the bacterial survival percentage. Extremely Random Trees performed the best among these models with 95.08% accuracy. A feature relevance analysis extracted the most significant attributes to predict the bacterial survival percentage. Lanthanum content and particle size were irrelevant, despite what can be assumed. This approach offers a promising avenue for developing effective and tailored strategies to reduce the time and cost of developing antimicrobial nanoparticles.

3.
Antioxidants (Basel) ; 13(2)2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38397812

RESUMEN

This study used a sonochemical synthesis method to prepare (La, Sm)-doped ZnO nanoparticles (NPs). The effect of incorporating these lanthanide elements on the structural, optical, and morphological properties of ZnO-NPs was analyzed. The cytotoxicity and the reactive oxygen species (ROS) generation capacity of ZnO-NPs were evaluated against breast (MCF7) and colon (HT29) cancer cell lines. Their antioxidant activity was analyzed using a DPPH assay, and their toxicity towards Artemia salina nauplii was also evaluated. The results revealed that treatment with NPs resulted in the death of 10.559-42.546% and 18.230-38.643% of MCF7 and HT29 cells, respectively. This effect was attributed to the ability of NPs to downregulate ROS formation within the two cell lines in a dose-dependent manner. In the DPPH assay, treatment with (La, Sm)-doped ZnO-NPs inhibited the generation of free radicals at IC50 values ranging from 3.898 to 126.948 µg/mL. Against A. salina nauplii, the synthesized NPs did not cause death nor induce morphological changes at the tested concentrations. A series of machine learning (ML) models were used to predict the biological performance of (La, Sm)-doped ZnO-NPs. Among the designed ML models, the gradient boosting model resulted in the greatest mean absolute error (MAE) (MAE 9.027, R2 = 0.86). The data generated in this work provide innovative insights into the influence of La and Sm on the structural arrangement and chemical features of ZnO-NPs, together with their cytotoxicity, antioxidant activity, and in vivo toxicity.

4.
Molecules ; 29(2)2024 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-38257300

RESUMEN

In 2021, global plastics production was 390.7 Mt; in 2022, it was 400.3 Mt, showing an increase of 2.4%, and this rising tendency will increase yearly. Of this data, less than 2% correspond to bio-based plastics. Currently, polymers, including elastomers, are non-recyclable and come from non-renewable sources. Additionally, most elastomers are thermosets, making them complex to recycle and reuse. It takes hundreds to thousands of years to decompose or biodegrade, contributing to plastic waste accumulation, nano and microplastic formation, and environmental pollution. Due to this, the synthesis of elastomers from natural and renewable resources has attracted the attention of researchers and industries. In this review paper, new methods and strategies are proposed for the preparation of bio-based elastomers. The main goals are the advances and improvements in the synthesis, properties, and applications of bio-based elastomers from natural and industrial rubbers, polyurethanes, polyesters, and polyethers, and an approach to their circular economy and sustainability. Olefin metathesis is proposed as a novel and sustainable method for the synthesis of bio-based elastomers, which allows for the depolymerization or degradation of rubbers with the use of essential oils, terpenes, fatty acids, and fatty alcohols from natural resources such as chain transfer agents (CTA) or donors of the terminal groups in the main chain, which allow for control of the molecular weights and functional groups, obtaining new compounds, oligomers, and bio-based elastomers with an added value for the application of new polymers and materials. This tendency contributes to the development of bio-based elastomers that can reduce carbon emissions, avoid cross-contamination from fossil fuels, and obtain a greener material with biodegradable and/or compostable behavior.


Asunto(s)
Elastómeros , Plásticos , Polímeros , Goma , Poliuretanos
5.
J Leukoc Biol ; 113(1): 1-10, 2023 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-36822163

RESUMEN

Hyperinflammation present in individuals with severe COVID-19 has been associated with an exacerbated cytokine production and hyperactivated immune cells. Endoplasmic reticulum stress leading to the unfolded protein response has been recently reported as an active player in inducing inflammatory responses. Once unfolded protein response is activated, GRP78, an endoplasmic reticulum-resident chaperone, is translocated to the cell surface (sGRP78), where it is considered a cell stress marker; however, its presence has not been evaluated in immune cells during disease. Here we assessed the presence of sGRP78 on different cell subsets in blood samples from severe or convalescent COVID-19 patients. The frequency of CD45+sGRP78+ cells was higher in patients with the disease compared to convalescent patients. The latter showed similar frequencies to healthy controls. In patients with COVID-19, the lymphoid compartment showed the highest presence of sGRP78+ cells versus the myeloid compartment. CCL2, TNF-α, C-reactive protein, and international normalized ratio measurements showed a positive correlation with the frequency of CD45+sGRP78+ cells. Finally, gene expression microarray data showed that activated T and B cells increased the expression of GRP78, and peripheral blood mononuclear cells from healthy donors acquired sGRP78 upon activation with ionomycin and PMA. Thus, our data highlight the association of sGRP78 on immune cells in patients with severe COVID-19.


Asunto(s)
COVID-19 , Chaperón BiP del Retículo Endoplásmico , Humanos , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Leucocitos Mononucleares/metabolismo , COVID-19/metabolismo , Chaperonas Moleculares/genética , Retículo Endoplásmico/metabolismo , Estrés del Retículo Endoplásmico
7.
Polymers (Basel) ; 14(22)2022 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-36433100

RESUMEN

Biobased hydroxyl-terminated polybutadiene (HTPB) was successfully synthesized in a one-pot reaction via metathesis degradation of industrial rubbers. Thus, polybutadiene (PB) and poly(styrene-butadiene-styrene) (SBS) were degraded via metathesis with high yields (>94%), using the fatty alcohol 10-undecen-1-ol as a chain transfer agent (CTA) and the second-generation Grubbs−Hoveyda catalyst. The identification of the hydroxyl groups (-OH) and the formation of biobased HTPB were verified by FT-IR and NMR. Likewise, the molecular weight and properties of the HTPB were controlled by changing the molar ratio of rubber to CTA ([C=C]/CTA) from 1:1 to 100:1, considering a constant molar ratio of the catalyst ([C=C]/Ru = 500:1). The number average molecular weight (Mn) ranged between 583 and 6580 g/mol and the decomposition temperatures between 134 and 220 °C. Moreover, the catalyst optimization study showed that at catalyst loadings as low as [C=C]/Ru = 5000:1, the theoretical molecular weight is in good agreement with the experimental molecular weight and the expected diols and polyols are formed. At higher ratios than those, the difference between theoretical and experimental molecular weight is wide, and there is no control over HTPB. Therefore, the rubber/CTA molar ratio and the amount of catalyst play an important role in PB degradation and HTPB synthesis. Biobased HTPB can be used to synthesize engineering design polymers, intermediates, fine chemicals, and in the polyurethane industry, and contribute to the development of environmentally friendly raw materials.

8.
Int J Mol Sci ; 23(9)2022 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-35562910

RESUMEN

Unsaturated copolyesters are of great interest in polymer science due to their broad potential applications and sustainability. Copolyesters were synthesized from the ring-opening metathesis copolymerization of ω-6-hexadecenlactone (HDL) and norbornene (NB) using ruthenium-alkylidene [Ru(Cl2)(=CHPh)(1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene)(PCy3)] (Ru1), [Ru(Cl)2(=CHPh)(PCy3)2] (Ru2), and ruthenium-vinylidene [RuCl2(=C=CH(p-C6H4CF3))(PCy3)2] (Ru3) catalysts, respectively, yielding HDL-NB copolymers with different ratios of the monomer HDL in the feed. The activity of N-heterocyclic-carbene (NHC) (Ru1) and phosphine (Ru2 and Ru3) ligands containing ruthenium-carbene catalysts were evaluated in the synthesis of copolymer HDL-NB. The catalysts Ru1 with an NHC ligand showed superior activity and stability over catalysts Ru2 and Ru3 bearing PCy3 ligands. The incorporation of the monomers in the copolymers determined by 1H-NMR spectroscopy was similar to that of the HDL-NB values in the feed. Experiments, at distinct monomer molar ratios, were carried out using the catalysts Ru1-Ru3 to determine the copolymerization reactivity constants by applying the Mayo-Lewis and Fineman-Ross methods. The copolymer distribution under equilibrium conditions was studied by the 13C NMR spectra, indicating that the copolymer HDL-NB is a gradient copolymer. The main factor determining the decrease in melting temperature is the inclusion of norbornene units, indicating that the PNB units permeate trough the HDL chains. The copolymers with different molar ratios [HDL]/[NB] have good thermal stability up to 411 °C in comparison with the homopolymer PHDL (384 °C). Further, the stress-strain measurements in tension for these copolymers depicted the appreciable increment in stress values as the NB content increases.


Asunto(s)
Rutenio , Cinética , Ligandos , Metano/análogos & derivados , Norbornanos/química , Polímeros/química , Rutenio/química
9.
Polymers (Basel) ; 13(1)2020 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-33396908

RESUMEN

The future availability of synthetic polymers is compromised due to the continuous depletion of fossil reserves; thus, the quest for sustainable and eco-friendly specialty polymers is of the utmost importance to ensure our lifestyle. In this regard, this study reports on the use of oleic acid as a renewable source to develop new ionomers intended for proton exchange membranes. Firstly, the cross-metathesis of oleic acid was conducted to yield a renewable and unsaturated long-chain aliphatic dicarboxylic acid, which was further subjected to polycondensation reactions with two aromatic diamines, 4,4'-(hexafluoroisopropylidene)bis(p-phenyleneoxy)dianiline and 4,4'-diamino-2,2'-stilbenedisulfonic acid, as comonomers for the synthesis of a series of partially renewable aromatic-aliphatic polyamides with an increasing degree of sulfonation (DS). The polymer chemical structures were confirmed by Fourier transform infrared (FTIR) and nuclear magnetic resonance (1H, 13C, and 19F NMR) spectroscopy, which revealed that the DS was effectively tailored by adjusting the feed molar ratio of the diamines. Next, we performed a study involving the ion exchange capacity, the water uptake, and the proton conductivity in membranes prepared from these partially renewable long-chain polyamides, along with a thorough characterization of the thermomechanical and physical properties. The highest value of the proton conductivity determined by electrochemical impedance spectroscopy (EIS) was found to be 1.55 mS cm-1 at 30 °C after activation of the polymer membrane.

10.
J Comp Eff Res ; 6(3): 195-204, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28485691

RESUMEN

BACKGROUND: The human papillomavirus (HPV) vaccine has recently attracted considerable attention in emerging countries, due to its potential to reduce the impact of HPV-related diseases. This case study sheds new light about the variety of HTA arrangements, methods and processes involved in the adoption and use of HPV vaccines in a selected sample of central, eastern and southern Europe and Latin America and the Caribbean, all of them emerging in the use of HTA. MATERIALS & METHODS: A multi-country case study was designed. Mixed methods, document review, semi-structured surveys and personal communication with experts, were used for data collection and triangulation. RESULTS: This study shows that common elements of good practice exist in the processes and methods used, with all countries arriving at the same appraisal recommendations. However, the influence of socio-politico-economic factors appears to be determinant on the final decisions and restrictions to access made. CONCLUSION: This case study intends to draw useful lessons for policymakers in emerging settings interested in the adoption of the HPV vaccine supported by evidence-informed processes, such as those offered by institutionalized HTA. Future studies are also recommended to elucidate the specific roles that social values and uncertainties play in vaccine decision-making across different societies.


Asunto(s)
Infecciones por Papillomavirus/prevención & control , Vacunas contra Papillomavirus/uso terapéutico , Brasil , Región del Caribe , Colombia , Países en Desarrollo , Europa (Continente) , Humanos , América Latina , Polonia
11.
Artículo en Inglés | MEDLINE | ID: mdl-27783925

RESUMEN

In this work, we studied the characteristics of recovery from desensitization of the light-elicited current of crayfish. Applying a two-flash protocol, we found that the first flash triggers a current that activates with a noticeable latency, reaches a peak value, and thereafter decays along a single exponential time course. In comparison with the first-elicited current, the current elicited by the second flash not only presents an expected smaller peak current, depending on the time between flashes, but it also displays a different latency and decay time constant. Recovery of the first flash values of these current parameters depends on the circadian time at which the experiments are conducted, and on the presence of pigment-dispersing hormone. Our data also suggest the existence of distinctive desensitized states, whose induction depends on circadian time and the presence of pigment-dispersing hormone.


Asunto(s)
Astacoidea/fisiología , Ritmo Circadiano , Hormonas de Invertebrados/metabolismo , Células Fotorreceptoras de Invertebrados/fisiología , Algoritmos , Animales , Acuicultura , Astacoidea/crecimiento & desarrollo , Fenómenos Electrofisiológicos , Ojo , Técnicas In Vitro/veterinaria , Cinética , Muda , Tiempo de Reacción
12.
Cienc. enferm ; 21(1): 103-113, abr. 2015. tab, graf
Artículo en Español | LILACS, BDENF - Enfermería | ID: lil-748765

RESUMEN

Objetivo: Determinar la agencia de autocuidado en los estudiantes de nuevo ingreso en la Unidad Académica Multidisciplinaria Zona Media. Material y método: Estudio descriptivo, correlacional, de corte transversal. Muestra de 281 alumnos de nuevo ingreso de la Unidad Académica Multidisciplinaria Zona Media de México, de las diferentes carreras. Resultados: El cuestionario fue contestado por un total de 315 estudiantes, quedando 34 excluidos, de acuerdo a los criterios de inclusión y exclusión antes mencionados. Por lo tanto, se consiguió un total de participación de 281 alumnos. Encontramos que el 54% de la población en estudio maneja un nivel de autocuidado medio, el 42% un alto nivel de autocuidado y solo el 4% un nivel bajo. Conclusión: El 100% de los estudiantes conocían el concepto de autocuidado, por lo que se podría deducir que el conocimiento específico acerca de autocuidado no influye en la realización de menores o mayores prácticas de autocuidado; la Universidad en sí no constituyó una gran enseñanza de autocuidado, por lo que en este aspecto le corresponde fortalecer en sus alumnos el conocimiento y las habilidades para que puedan tomar decisiones acerca de su salud, a través de una mejor promoción.


Objective: Determine the self-care agency in the freshmen in Multidisciplinary Academic Unit Zona Media. Design: Provide information making them partners for a proper personal care to each of them, counting with the support of teachers and advisers to carry out previous interventions of self-care using didactic and practical material. Methodology: Descriptive, study Correlacional, non-Experimental and transversal cutting. It shows again of 281 student's entrance of the Unidad Académica Multidisciplinaria Zona Media of the different careers. Results: The questionnaire was answered by a total of 315 students, being excluded 34, according to the afore mentioned criteria of inclusion and exclusion. Therefore, it got a total of 281 student participation. We found that 54% of the population under study manage a level of self-management, 42% a high level of self-care and only 4% a low level. Conclusion: 100% of the students knew the concept of self-care, so it could deduce that specific knowledge about self-care has no influence on the realization of juvenile or older practice of self-care; the University itself, did not constitute a great teaching of self-care, so here is strengthen in students the knowledge and skills so they can make decisions about your health, through a better promotion.


Asunto(s)
Humanos , Autocuidado , Estudiantes de Enfermería , Epidemiología Descriptiva , Encuestas y Cuestionarios , México
13.
Molecules ; 17(5): 6001-10, 2012 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-22609789

RESUMEN

This study reports on the degradation of natural rubber (NR) via crossmetathesis with mandarin oil and d-limonene, an abundant compound in essential oils; that were used as chain transfer agents (CTAs) and green solvents. Reactions were performed in the presence of the ruthenium-alkylidene catalysts (PCy3)2(Cl)2Ru=CHPh (I) and (1,3-dimesityl-4,5-dihydroimidazol-2-ylidene) (PCy3)Cl2Ru=CHPh (II), respectively. Catalyst II bears an N-heterocyclic carbene ligand (NHC) bounded to the ruthenium atom, which has a strong basic character; therefore it is more active toward trisubstituted olefins in comparison with catalyst I. In both cases, isolated monoterpene-terminated isoprene oligomers were obtained as products of the cross-metathesis degradation of NR. In the presence of catalyst II molecular weight values around M(n) × 10² and yields of 80% were obtained; whereas with catalyst I, the molecular weights of products were about M(n) × 104 with yields ranging 70 to 74%. The composition and yield of NR degradation products were determined by GC/MS (EI) analysis and it was found that the oligomers obtained have primarily one vinyl group and one terpene-monocyclic group at the chain end, with isoprene units A(m) = 2, 3 y 4.


Asunto(s)
Ciclohexenos/química , Aceites de Plantas/química , Goma/química , Rutenio/química , Terpenos/química , Catálisis , Citrus/química , Cromatografía de Gases y Espectrometría de Masas , Limoneno , Resonancia Magnética Nuclear Biomolecular
14.
Transfusion ; 51(2): 328-32, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21309778

RESUMEN

BACKGROUND: In January 2005, the Cord Blood Bank (CBB) at the Mexican Institute of Social Security initiated activities. Herein, we describe the experience generated during this period (January 1, 2005-December 31, 2009). STUDY DESIGN AND METHODS: Good manufacturing practices and standard operating procedures were used to address donor selection, as well as umbilical cord blood (UCB) collection, processing, and cryopreservation. Based mainly on HLA and nucleated cell content, specific UCB units were thawed, processed, and released for transplantation. RESULTS: A total of 589 UCB units were stored, representing 54% of the total number of units collected. Forty-eight units (8.14% of the stored units) were released for transplantation of 36 patients. Twenty-six patients (72% of cases) corresponded to patients with acute leukemia, five (14%) to patients with marrow failure, and the rest (five; 14%) to patients with hemoglobinopathies and other syndromes. The median number of nucleated cells infused per patient was 6.71 × 10(7) /kg and the median number of CD34+ cells was 4.8 × 10(5) /kg. Current engraftment data indicate that engraftment occurred in 56%, and no engraftment in 44%, of cases. Engraftment was more frequent (59%) in patients that received more than 3 × 10(7) total nucleated cells (TNCs)/kg body weight, than in those receiving fewer than 3 × 10(7) TNCs/kg (40%). Myeloid engraftment was observed 7 to 54 days posttransplant (median, 23 days), whereas platelet engraftment was detected on Days 12 to 87 posttransplant (median, 38 days). To date, the disease-free survival rate was 41% and the overall survival was 47%, with survival periods of 126 to 1654 days. CONCLUSION: Although the experience presented herein is still limited and the period of analysis is still short, the results obtained during these 5 years are encouraging.


Asunto(s)
Bancos de Sangre/estadística & datos numéricos , Trasplante de Células Madre de Sangre del Cordón Umbilical/estadística & datos numéricos , Sangre Fetal , Anemia Aplásica/terapia , Recuento de Células Sanguíneas , Núcleo Celular , Supervivencia sin Enfermedad , Supervivencia de Injerto , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/ultraestructura , Hemoglobinopatías/terapia , Humanos , Recién Nacido , Leucemia/terapia , México , Estudios Retrospectivos , Seguridad Social , Resultado del Tratamiento
15.
Rev Med Inst Mex Seguro Soc ; 48(2): 117-9, 2010.
Artículo en Español | MEDLINE | ID: mdl-20929612

RESUMEN

The World Health Organization considers to the American trypanosomiasis a disease with priority attention that cause 45 000 deaths annually. We are celebrating a century of the disease description and the identification of etiologic agent and the transmitter. The universal screen strategy had diminished the risk of transmission by blood transfusion. In this number, Novelo Garza ET AL. described the national prevalence in Mexico through a screen test that led us watch the first geographical image of the disease in the country.


Asunto(s)
Transfusión Sanguínea/normas , Enfermedad de Chagas/prevención & control , Enfermedad de Chagas/transmisión , Humanos , México
16.
J Clin Periodontol ; 33(10): 743-8, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16899025

RESUMEN

AIM: To determine the proportion of bacteria resistant to amoxicillin and doxycycline in subgingival plaque samples from Mexican subjects. MATERIALS AND METHODS: Two subgingival plaque samples were taken from 20 Mexican subjects. Samples were dispersed, diluted and plated on non-antibiotic agar plates and on plates containing 0.5, 1, 2, 4, 8 and 16 microg/ml of either amoxicillin or doxycycline. The proportion of resistant bacteria was calculated based on the total number of colony-forming units present in the non-antibiotic containing plates. RESULTS: On average, 0.4-13.4% and 0.9-20.4% of the total cultivable subgingival microbiota was resistant to the concentrations tested of amoxicillin and doxycycline, respectively. The differences between antibiotics were statistically significant for the 0.5, 2 and 4 mug/ml concentrations (p < 0.05, Wilcoxon's test). CONCLUSIONS: Our findings revealed that a relatively small proportion of the total cultivable subgingival microbiota from Mexican subjects was resistant to amoxicillin and doxycycline.


Asunto(s)
Bacterias/clasificación , Placa Dental/microbiología , Farmacorresistencia Bacteriana , Adulto , Amoxicilina/farmacología , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Técnicas Bacteriológicas , Recuento de Colonia Microbiana , Doxiciclina/farmacología , Femenino , Bacterias Gramnegativas/clasificación , Bacterias Gramnegativas/efectos de los fármacos , Humanos , Masculino , México , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Resistencia a las Penicilinas , Resistencia a la Tetraciclina
17.
Rev Med Inst Mex Seguro Soc ; 44(3): 227-33, 2006.
Artículo en Español | MEDLINE | ID: mdl-16870116

RESUMEN

INTRODUCTION: There are no records on the prevalence of infection by HCV in Mexican population. The central area of Mexico is a highly dense demographic zone and is the influence area of the second blood bank in Latin America in terms of affluence. MATERIAL AND METHODS: We prospectively studied the prevalence and genotypes of HCV infection in 5105 individuals attending the Central Blood Bank of Centro Médico Nacional La Raza regardless if they were accepted or rejected as donors. We applied a quimiolumiscence assay as a screening test. A recombinant immunoassay (RIBA) and a qualitative polymerase chain reaction (PCR) were performed as confirmatory tests and to detect viremia, respectively. Virus genotype was identified by means of a Line Immuno Probe Assay in PCR positive samples. RESULTS: The overall prevalence of HCV infection was 0.195% (10/5105). Viremia was detected in 90% of the subjects. The prevalence of accepted donors (0.087%) was significantly lower (p = 0.017) than that of the rejected ones (0.421%). Among viremic subjects, 60 % were infected with genotype 2 and 40% with a subtype combination (a/b) of genotype 1. DISCUSSION: The prevalence of HCV infection in our population was significantly lower than the world mean prevalence estimated in 3 %. A higher prevalence of genotype 2 in asymptomatic individuals contrasts with previous studies with a selected population where genotype 1 prevailed.


Asunto(s)
Bancos de Sangre , Hepacivirus/aislamiento & purificación , Hepatitis C/epidemiología , Hepatitis C/virología , Adulto , Femenino , Humanos , Masculino , México/epidemiología , Prevalencia
18.
J Autoimmun ; 21(3): 273-6, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14599852

RESUMEN

CD4+ T cells that constitutively express CD25 exhibit powerful suppressive properties. Such cells have been denominated regulatory T cells (T(R)). Alterations in T(R)cells are known to cause organ-specific autoimmune disease in animal models. The aim of this work was to quantify CD4+CD25+ T cells in patients with systemic lupus erythematosus (SLE). Thirty untreated patients (ten with active disease) and ten healthy volunteers were studied. Flow cytometry was used to quantify cell populations. CD4+CD69+, CD4+CD25+ and CD4+CD25(bright) cells were considered. Peripheral blood mononuclear cell cultures were performed and supernatants collected for IL-10 and 12 measurement. CD4+CD25+ cells were significantly decreased in patients with active disease when compared to control subjects and patients without disease activity (P<0.001). CD4+CD69+ cells were increased in patients with active disease when compared to controls (P=0.041). Accordingly, CD4+CD25(bright) cells were decreased in patients with active disease compared to healthy subjects (P<0.001). IL-12 production was hampered in cells from patients during periods of active disease when compared to healthy controls and patients during remission (P<0.001). We observed a correlation between decreased T(R)number and reduced IL-12 mononuclear cell production (r=0.362, P=0.05). This work demonstrates that CD4+CD25+ T cells are decreased in patients with clinically active SLE.


Asunto(s)
Lupus Eritematoso Sistémico/inmunología , Linfocitos T/fisiología , Antígenos CD/análisis , Antígenos de Diferenciación de Linfocitos T/análisis , Antígenos CD4/análisis , Interpretación Estadística de Datos , Citometría de Flujo , Humanos , Interleucina-10/metabolismo , Interleucina-12/metabolismo , Lectinas Tipo C , Leucocitos Mononucleares/química , Lupus Eritematoso Sistémico/sangre , Recuento de Linfocitos , Receptores de Interleucina-2/análisis , Linfocitos T/química
19.
Cir. & cir ; Cir. & cir;67(3): 112-8, mayo-jun. 1999. ilus
Artículo en Español | LILACS | ID: lil-254553

RESUMEN

Se presentan cinco casos con duplicación del intestino delgado, dos con hemorragia abundante del tubo digestivo, sindrome anémico, vómito y distensión abdominal generalizada, dos casos presentaron signos de obstrucción intestinal, con masa abdominal y otro presentó masa abdominal móvil, quística y no dolorosa. Ninguno tuvo otra malformación agregada. El ultrasonido (US) prenatal demostró en un caso, la presencia de imagen quística en el abdomen fetal, que se confirmó al nacimiento, las radiografías simples del abdomen (RxSA) mostraron opacidad total o parcial del abdomen y dilatación de las asas intestinales. La tomografía axial computada (TAC) presentó en un caso tumoración abdominal. A dos casos se les realizó estudio con TC 99m para descartar divertículo de Meckel y mucosa gástrica ectópica y fue negativo. Se realizó laparotomía de urgencia a dos casos y en tres fue pogramada. En los cinco casos se encontró duplicación de íleon, que se resecó y se realizó entero-entero anastomosis término-terminal en un plano. El estudio histopatológico demostró la presencia de mucosa intestinal normal. En un caso hubo dos duplicaciones de tipo sacular sobre el borde mesentérico del intestino sano del íleon


Asunto(s)
Humanos , Masculino , Femenino , Recién Nacido , Lactante , Hemorragia Gastrointestinal/etiología , Íleon/anomalías , Íleon/cirugía , Enfermedades Intestinales/congénito , Enfermedades Intestinales/diagnóstico , Intestino Delgado/anomalías , Intestino Delgado/cirugía , Laparotomía
20.
Cir. & cir ; Cir. & cir;65(2): 33-8, 1997. tab, ilus
Artículo en Español | LILACS | ID: lil-217435

RESUMEN

Se analizan los casos de dilatación quística congénita del colédoco (DQCC) tratados en el Servicio de Cirugía Pediátrica del Hospital Juárez de México, SSA de 1974 a 1996. La DQCC es poco frecuente en los niños mexicanos y el tratamiento fue la derivación interna, la excisión total del quiste con hepáticoyeyunoanastomosis en Y de Roux y actualmente con un segmento aislado de yeyuno del hepático a la mitad inferior de la segunda porción del duodeno; con la creación de una válvula a la mitad del yeyuno aislado. Se realizó un estudio retrospectivo de 17 expedientes de pacientes pediátricos con DQCC operados entre 1974 y 1996. Se presenta su evaluación clínica, frecuencia, cirugía, complicaciones y seguimiento. El primer paciente fue tratado con cistoyeyunoanastomosis en Y de Roux y colecistectomía, presentó estenosis de la anastomosis y colangitis de repetición, que requirió excisión total del quiste. Cuatro de 13 pacientes tratados con excisión del quiste, hepáticoyeyunoanastomosis en Y de Roux y colecistectomía fueron reoperados, dos por biliperitoneo, uno por hemorragia y uno por absceso intraperitoneal. A los tres últimos pacientes se les realizó excisión total del quiste e interposición de un segmento de yeyuno con la creación de una válvula antirreflujo y están asintomáticos. Ningún paciente tiene el riesgo de cáncer ni falleció. La DQCC puede diagnosticarse desde la etapa fetal hasta la vejez. El tratamiento quirúrgico actual es la excisción total del quiste con Y de Roux y colecistectomía, desde 1981 con interposición de un segmento de yeyuno con válvula antirreflujo, que va del hepático al duodeno, con excelentes resultados, que evitan el reflujo, la colangitis y disminuye el riesgo de presentar colangiocarcinoma


Asunto(s)
Humanos , Masculino , Femenino , Lactante , Preescolar , Adolescente , Dilatación , Yeyuno/cirugía , Complicaciones Posoperatorias , Quiste del Colédoco/cirugía , Quiste del Colédoco/diagnóstico , Reoperación
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