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1.
Salud Publica Mex ; 64(3, may-jun): 333-339, 2022 Jun 02.
Artículo en Español | MEDLINE | ID: mdl-36130376

RESUMEN

Desde el comienzo de la pandemia de Covid-19 los servi-cios de prevención de cáncer de mama han sido aplazados gravemente. Esta acción provocó la reducción en el número acumulado de mastografías de detección a nivel mundial e incrementó las disparidades en salud, sobre todo entre las mujeres vulnerables. Si bien la evidencia que respalda las es-trategias para rescatar el tamizaje con mastografía en la fase de resolución de la pandemia no es suficiente, hay algunas consideraciones pragmáticas que pueden guiar su recupera-ción y garantizar su continuidad. Una de estas estrategias es prever los retrasos en el tamizaje y abordarlos a través de programas seguros que se alineen con la situación epidemio-lógica actual. Las acciones planteadas en el presente ensayo están en consonancia con las iniciativas internacionales de garantizar la continuidad de los programas de tamizaje de cáncer de mama en atención a que el cuidado de las mujeres sea una acción prioritaria, continua y permanente.


Asunto(s)
Neoplasias de la Mama , COVID-19 , COVID-19/epidemiología , Detección Precoz del Cáncer , Femenino , Humanos , Pandemias
2.
BMC Infect Dis ; 21(1): 510, 2021 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-34059022

RESUMEN

OBJECTIVE: To determine the prevalence of Latent Tuberculosis in patients with hematological neoplasms at the Instituto Nacional de Cancerología in Mexico City using the Tuberculin skin test (TST). METHODS: This retrospective study included all patients with a recent diagnosis of hematological neoplasms who were admitted for treatment from 2017 to 2018 and who were screened for latent tuberculosis with the TST. The prevalence of latent tuberculosis in this group, tolerance and therapeutic adherence in treated patients are described. RESULTS: The files of 446 patients with hematological malignancy who had a TST were reviewed. The prevalence of latent tuberculosis was 31.2% (n = 139). Ninety-three patients received isoniazid, 15.1% had some adverse reactions, but only 4 (4.3%) had to discontinue treatment. Two patients with latent tuberculosis under treatment with Isoniazid reactivated tuberculosis infection. CONCLUSIONS: The prevalence in our study was within the range of other similar Mexican populations. Isoniazid treatment had an adequate tolerance and adherence. Longer follow-up could offer more information on the risk of reactivation in both groups.


Asunto(s)
Neoplasias Hematológicas/epidemiología , Tuberculosis Latente/epidemiología , Adulto , Antituberculosos/efectos adversos , Antituberculosos/uso terapéutico , Instituciones Oncológicas , Femenino , Neoplasias Hematológicas/microbiología , Humanos , Isoniazida/efectos adversos , Isoniazida/uso terapéutico , Tuberculosis Latente/diagnóstico , Tuberculosis Latente/tratamiento farmacológico , Masculino , México/epidemiología , Persona de Mediana Edad , Mycobacterium tuberculosis/efectos de los fármacos , Prevalencia , Estudios Retrospectivos , Prueba de Tuberculina , Tuberculosis/epidemiología , Tuberculosis/etiología
3.
Biol Res ; 54(1): 21, 2021 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-34289913

RESUMEN

BACKGROUND: Chagas disease is considered important and presents intense inflammatory and fibrotic processes induced by the perpetuation of the parasite in the affected tissues and organs. Therefore, it is necessary to inquire about the host defense and attack mechanisms to have a more detailed knowledge about Chagas disease. MicroRNAs are found in blood, tissues and extracellular vesicles. These small regulators of gene expression are involved in physiological and pathological processes in both mammals and parasites. Several microRNAs have deregulated expression in chagasic heart disease, although little is known about their extracellular expression. Our main objective was to evaluate the involvement of miR-21, miR-146a and miR-155 in several samples from mice infected with the TcI Ninoa strain from the acute and indeterminate phases. We also explored a potential functional association of the selected microRNAs using STRING software. This software identified 23 pathways associated with Trypanosoma cruzi infection. In addition, eleven genes were identified through bioinformatics analysis, and we found that SMAD family member 5 was downregulated in both phases. This gene serves as a mediator in the TGF-ß signaling pathway. Thus, forty female mice of the CD1 strain were distributed into 4 groups and the expression levels of miR-21, miR-146a and miR-155 were measured in samples of heart tissue, total plasma and plasma extracellular vesicles by quantitative real-time polymerase chain reaction. RESULTS: Overexpression of miR-21, miR-146a and miR-155 was observed in heart and plasma in both phases. Moreover, in extracellular vesicles miR-21 and miR-146a were also overexpressed in the acute phase, whereas in the indeterminate chronic phase we found only miR-146a up-regulated. CONCLUSIONS: The expression of inflammatory microRNAs miR-21, miR-146a and miR-155 were up-regulated in each of the samples from acutely and chronically infected mice. The relevant finding was that miR-146a was up-regulated in each sample in both phases; therefore, this miRNA could be a possible candidate biomarker in Chagas disease.


Asunto(s)
Enfermedad de Chagas , MicroARNs , Animales , Biomarcadores , Enfermedad de Chagas/genética , Biología Computacional , Femenino , Fibrosis , Ratones , MicroARNs/genética
4.
Environ Sci Technol ; 54(4): 2103-2111, 2020 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-31909600

RESUMEN

Amid climate change and public health concerns, world economies are seeking to reduce the greenhouse gas emissions and local air pollution from transportation. Population growth in cities worldwide will further increase demand for clean and affordable transportation. We propose a city-specific environmental justice mapping index, inspired by a similar index used in California, that highlights promising areas for clean transportation interventions in Greater Mexico City to reduce greenhouse gas emissions and local pollution. This novel approach leverages highly spatially resolved population, pollution, and transportation data. The proposed index score is designed as an open source, updateable point of orientation for decisionmakers as they consider investment in transportation electrification from the standpoint of overlapping atmospheric pollution and social vulnerability.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , California , Ciudades , México , Marginación Social , Transportes
5.
Molecules ; 25(24)2020 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-33302377

RESUMEN

Due to the emergence of multidrug-resistant pathogens, it is necessary to develop options to fight infections caused by these agents. Lactoferrin (Lf) is a cationic nonheme multifunctional glycoprotein of the innate immune system of mammals that provides numerous benefits. Lf is bacteriostatic and/or bactericidal, can stimulate cell proliferation and differentiation, facilitate iron absorption, improve neural development and cognition, promote bone growth, prevent cancer and exert anti-inflammatory and immunoregulatory effects. Lactoferrin is present in colostrum and milk and is also produced by the secondary granules of polymorphonuclear leukocytes, which store this glycoprotein and release it at sites of infection. Lf is also present in many fluids and exocrine secretions, on the surfaces of the digestive, respiratory and reproductive systems that are commonly exposed to pathogens. Apo-Lf (an iron-free molecule) can be microbiostatic due to its ability to capture ferric iron, blocking the availability of host iron to pathogens. However, apo-Lf is mostly microbicidal via its interaction with the microbial surface, causing membrane damage and altering its permeability function. Lf can inhibit viral entry by binding to cell receptors or viral particles. Lf is also able to counter different important mechanisms evolved by microbial pathogens to infect and invade the host, such as adherence, colonization, invasion, production of biofilms and production of virulence factors such as proteases and toxins. Lf can also cause mitochondrial and caspase-dependent regulated cell death and apoptosis-like in pathogenic yeasts. All of these mechanisms are important targets for treatment with Lf. Holo-Lf (the iron-saturated molecule) can contain up to two ferric ions and can also be microbicidal against some pathogens. On the other hand, lactoferricins (Lfcins) are peptides derived from the N-terminus of Lf that are produced by proteolysis with pepsin under acidic conditions, and they cause similar effects on pathogens to those caused by the parental Lf. Synthetic analog peptides comprising the N-terminus Lf region similarly exhibit potent antimicrobial properties. Importantly, there are no reported pathogens that are resistant to Lf and Lfcins; in addition, Lf and Lfcins have shown a synergistic effect with antimicrobial and antiviral drugs. Due to the Lf properties being microbiostatic, microbicidal, anti-inflammatory and an immune modulator, it represents an excellent natural alternative either alone or as adjuvant in the combat to antibiotic multidrug-resistant bacteria and other pathogens. This review aimed to evaluate the data that appeared in the literature about the effects of Lf and its derived peptides on pathogenic bacteria, protozoa, fungi and viruses and how Lf and Lfcins inhibit the mechanisms developed by these pathogens to cause disease.


Asunto(s)
Antiinfecciosos/química , Antiinfecciosos/farmacología , Lactoferrina/química , Lactoferrina/farmacología , Péptidos/química , Péptidos/farmacología , Animales , Antiinfecciosos/síntesis química , Antiparasitarios/síntesis química , Antiparasitarios/química , Antiparasitarios/farmacología , Bacterias/efectos de los fármacos , Adhesión Bacteriana/efectos de los fármacos , Pared Celular/efectos de los fármacos , Técnicas de Química Sintética , Hongos/efectos de los fármacos , Interacciones Huésped-Patógeno , Humanos , Péptidos/síntesis química , Proteolisis/efectos de los fármacos , Relación Estructura-Actividad , Virulencia/efectos de los fármacos , Factores de Virulencia , Virus/efectos de los fármacos
6.
Ethn Health ; 23(7): 797-812, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-28277017

RESUMEN

OBJECTIVES: Latinos have poorer health outcomes among certain conditions (e.g. diabetes, obesity, mental health) compared to non-Latino Whites in the U.S., in part due to difference in the amount of physical activity, which are heavily influenced by sociocultural factors such as educational attainment and acculturation. Vigorous-intensity leisure time physical activity (VLTPA) may provide health benefits with a shorter amount of time than moderate-to-light physical activity. However, VLTPA has been significantly understudied compared to LTPA in general. The purpose of this study is to examine the associations between educational attainment, acculturation, and VLTPA by gender among Latino adults in the U.S. DESIGN: Nationally representative samples of Latino adults aged 25 years and older (n = 4393) from the 2010 National Health Interview Survey were analyzed. VLTPA was measured as the number of hours per week of VLTPA consisting of heavy sweating or large increases in breathing and heart rate. Acculturation was measured as the degree to which the English language versus the Spanish language was spoken most often. The zero-inflated Poisson regression model was constructed using the full information maximum likelihood estimation and controlling for a series of sociodemographic characteristics and relevant health behaviors. RESULTS: Educational attainment was positively associated with VLTPA among Latino adults [exp(b) = 1.09, p < 0.05)]. Similarly, greater acculturation was associated with greater hours/week of VLTPA [exp(b) = 1.10, p < 0.05)]. Lastly, the effect of educational attainment on VLTPA significantly varied by gender. CONCLUSIONS: Education had a positive association and acculturation had negative association with the hours/week of VLTPA among Latinos. Also, the association between education and VLTPA was significantly stronger among women than men. These findings inform culturally and socially sensitive approaches to improve the health of Latinos, in hopes to address health disparities by race/ethnicity the U.S.


Asunto(s)
Aculturación , Escolaridad , Ejercicio Físico/fisiología , Hispánicos o Latinos/estadística & datos numéricos , Actividades Recreativas , Adulto , Femenino , Encuestas Epidemiológicas , Humanos , Masculino , Persona de Mediana Edad , Obesidad , Factores Sexuales , Estados Unidos
7.
Polymers (Basel) ; 15(20)2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37896407

RESUMEN

Nowadays, solving the problems associated with environmental pollution is of special interest. Therefore, in this work, the morphology and thermal and mechanical properties of extruded fibers based on polylactic acid (PLA) and poly(butylene adipate-co-terephthalate) (PBAT) added to prickly pear flour (PPF) under composting for 3 and 6 months were evaluated. The highest weight loss percentage (92 ± 7%) was obtained after 6-month degradation of the PLA/PBAT/PPF/CO/AA blend, in which PPF, canola oil (CO), and adipic acid (AA) were added. Optical and scanning electron microscopy (SEM) revealed structural changes in the fibers as composting time increased. The main changes in the absorption bands observed by Fourier transform infrared spectroscopy (FTIR) were related to the decrease in -C=O (1740 cm-1) and -C-O (1100 cm-1) groups and at 1269 cm-1, associated with hemicellulose in the blends with PPF. Differential scanning calorimetry (DSC) showed an increase in the cold crystallization and melting point with degradation time, being more evident in the fibers with PPF, as well as a decrease in the mechanical properties, especially Young's modulus. The obtained results suggest that PPF residues could promote the biodegradability of PLA/PBAT-based fiber composites.

8.
Proc (Bayl Univ Med Cent) ; 35(2): 199-201, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35256820

RESUMEN

The novel coronavirus (COVID-19) pandemic has caused many deaths worldwide. Managing and diagnosing dermatological conditions has become difficult during this era, especially with the widespread administration of vaccines. We report a 58-year-old man with a history of psoriasis and multiple comorbidities who presented with a worsening pruritic rash 1 week after receiving the COVID-19 Pfizer vaccine. He was treated with triamcinolone-based wet wraps, triamcinolone ointment, and hydroxyzine, which improved his rash significantly after 6 days of hospitalization.

9.
Cardiovasc Revasc Med ; 39: 73-83, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34607787

RESUMEN

BACKGROUND: Spontaneous hemopericardium, associated with direct oral anticoagulant (DOAC) use, is one of the uncommon complications with high morbidity that has not been extensively studied We aimed to determine demographic characteristics, clinical features, lab evaluation, management, and outcomes of the studies focusing on hemopericardium as a DOAC use. METHODS: PubMed, Web of Science, Google Scholar, and CINAHL databases were searched for relevant articles using MeSH key-words and imported into referencing/review software. The data regarding demographics, clinical characteristics, cardiac investigations, and management were analyzed in IBM Statistics SPSS 21. t-Test and Chi-square test were used. A P score of <0.05 was considered statistically significant. RESULTS: After literature search, a total of 41 articles were selected for analysis. The mean age of the patients was 70.09 ± 11.06 years (p < 0.05); the majority of them were males (58.5%). Most of the patients presented with shortness of breath (75.2%) and had more than 3 co-morbid conditions (43.9%). The most frequently used anticoagulant was rivaroxaban (15/41; 36.6%); the common indication being arrhythmia (78.0%). CYP4503A4/P-Gp inhibitors (22.2%) were commonly used by the patients. Majority of the cases had a favorable outcome (95.1%). Pericardial tamponade was noted in 31/41 cases. Pericardiocentesis was performed in 37/41 cases. CONCLUSIONS: Hemopericardium from DOAC use has a favorable outcome but requires urgent pericardiocentesis. However, long term mortality, monitoring of DOAC activity, and drug-drug interactions have not been widely studied.


Asunto(s)
Anticoagulantes , Derrame Pericárdico , Administración Oral , Anciano , Anciano de 80 o más Años , Anticoagulantes/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Derrame Pericárdico/inducido químicamente , Derrame Pericárdico/diagnóstico por imagen , Derrame Pericárdico/terapia , Pericardiocentesis , Rivaroxabán
10.
Pan Afr Med J ; 43: 38, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36505013

RESUMEN

The novel coronavirus (COVID-19) has become a cause for global concern. Apart from a multitude of symptoms, the virus is known for its ability to cause loss of taste and smell that can be irreversible in a few cases. In fact, even after recovery, post-covid syndrome can still lead to devastating outcomes, specifically with reference to loss of smell and taste. A number of mechanisms that have been postulated include receptor-mediated uptake, increased inflammation, transneuronal migration, and direct damage to the olfactory pathway. Considering how important these two senses are, many psychological, social, and emotional repercussions can be expected. These repercussions include lowering of self-esteem and developmental of mental health issues. Long-term altered taste sensation can also lead to the development of unhealthy eating habits that can result in increasing risk for diabetes and hypertension. A few solutions have been investigated for treating these chemosensory dysfunctions, such as olfactory training, corticosteroids, theophylline and acupuncture. Although the results have been promising but a new modality, virtual reality, requires more in-depth exploration because it targets not only the dysfunction but also the mental health issues being experienced. It is important that affected individuals be provided with strong emotional and family support. Additionally, physicians can help the patients through support groups, cognitive behavioural therapy, olfactory, and virtual reality training.


Asunto(s)
Ageusia , COVID-19 , Terapia Cognitivo-Conductual , Médicos , Humanos , COVID-19/complicaciones , SARS-CoV-2
11.
Curr Probl Cardiol ; 47(11): 101331, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35870547

RESUMEN

Approximately 25% of patients with staphylococcus aureus bacteremia (SAB) develop infective endocarditis (IE), which has a consequent mortality of 25-46%. Current guidelines recommend routine transthoracic echocardiography (TTE) for patients with SAB; transesophageal echocardiogram (TEE) is reserved for those in whom initial TTE is negative and clinical suspicion for IE remains high. We sought to elucidate high risk features of SAB associated with the development of IE that warrant a TEE after a negative TTE. This retrospective study included 213 patients who were diagnosed with SAB at the University of New Mexico Hospital between 2010-2020. A pre-determined list of clinical risk factors along with TTE and TEE status was extracted from the electronic medical record. The primary outcome was development of IE in patients with SAB. Multivariate logistic regression analysis was used to identify clinical risk factors for IE. Moreover, sensitivity and specificity of TTE and TEE was calculated. Out of 213 patients with SAB, 68 patients met diagnostic criteria for IE. Most patients (n = 209) underwent TTE and 171 patients underwent subsequent TEE. The overall sensitivity of TTE was 63% and overall sensitivity of TEE was 88%. Multivariate analysis showed significantly increased risk of IE in patients who had implanted permanent pacemaker (aOR 32.3, CI 5.23 - 281, p < 0.001) and persistent fever (aOR 6.97, CI 2.42 - 21.0 P < 0.001). Based on our analysis, we recommend that TEE should be strongly considered after negative TTE in SAB patients with intracardiac prosthetics or persistent fever despite appropriate antibiotic therapy.


Asunto(s)
Bacteriemia , Endocarditis , Infecciones Estafilocócicas , Antibacterianos , Bacteriemia/complicaciones , Bacteriemia/diagnóstico , Bacteriemia/epidemiología , Ecocardiografía Transesofágica , Endocarditis/diagnóstico , Endocarditis/diagnóstico por imagen , Humanos , Estudios Retrospectivos , Factores de Riesgo , Infecciones Estafilocócicas/complicaciones , Infecciones Estafilocócicas/diagnóstico , Staphylococcus aureus
12.
Pulse (Basel) ; 9(3-4): 57-63, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35083171

RESUMEN

Sickle cell disease is an inherited hemoglobinopathy leading to the synthesis of hemoglobin S. Hemoglobin S results in the formation of abnormal sickle-shaped erythrocytes that lead to hematologic abnormalities such as hemolytic anemia and increased risks of thrombosis. Another particular problem encountered with the disease is pulmonary hypertension. The objective of this narrative review is to discuss the prevalence, pathophysiology mechanisms, diagnostic techniques, treatment options, and prognostic indicators in the setting of sickle cell disease with pulmonary hypertension. Additionally, the review also highlights other advancements that are being investigated. Considering the significant morbidity, mortality, and prevalence of pulmonary hypertension in patients with sickle cell disease, it is important to account for the aforementioned domains in the future guidelines to provide optimal and individualized care to the high-risk individuals as well as reduce the progression of disease, morbidity, and mortality rates.

13.
Sci Rep ; 11(1): 911, 2021 01 13.
Artículo en Inglés | MEDLINE | ID: mdl-33441581

RESUMEN

Worldwide, improper disposal of plastics is instigating environmental initiatives to combat plastics accumulation of in the environment and the world's oceans. Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) biocomposites with Miscanthus (Misc) fibres and distillers' dried grains with solubles (DDGS) were studied to ascertain if natural fibres and proteinaceous fillers can improve polyhydroxyalkanoate marine biodegradability. Using ASTM standard D7991-15, the biodegradation of PHBV, PHBV with Misc (15 and 25 wt%) and PHBV with DDGS (15 and 25 wt%) was performed in a simulated marine environment for the first time, as indicated by a literature survey. PHBV/Misc (85/15) and (75/25) biocomposites showed 15 and 25% more biodegradation compared to PHBV, respectively. Proteinaceous PHBV/DDGS (85/15) and (75/25) biocomposites showed 17 and 40% more biodegradation compared to PHBV, respectively. Furthermore, PHBV/Misc (75/25) and PHBV/DDGS (75/25) biocomposites were marine biodegraded in 412 and 295 days, respectively. In conclusion, proteinaceous fillers (DDGS) biocomposites have better marine biodegradability than miscanthus.

14.
Materials (Basel) ; 14(11)2021 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-34198954

RESUMEN

In order to provide a second economic life to agave fibers, an important waste material from the production of tequila, filaments based on polylactic acid (PLA) were filled with agave fibers (0, 3, 5, 10 wt%), and further utilized to produce biocomposites by fused deposition modeling (FDM)-based 3D printing at two raster angles (-45°/45° and 0°/90°). Differential scanning calorimetry, water uptake, density variation, morphology, and composting of the biocomposites were studied. The mechanical properties of the biocomposites (tensile, flexural, and Charpy impact properties) were determined following ASTM international norms. The addition of agave fibers to the filaments increased the crystallinity value from 23.7 to 44.1%. However, the fibers generated porous structures with a higher content of open cells and lower apparent densities than neat PLA pieces. The printing angle had a low significant effect on flexural and tensile properties, but directly affected the morphology of the printed biocomposites, positively influenced the impact strength, and slightly improved the absorption values for biocomposites printed at -45°/45°. Overall, increasing the concentrations of agave fibers had a detrimental effect on the mechanical properties of the biocomposites. The disintegration of the biocomposites under simulated composting conditions was slowed 1.6-fold with the addition of agave fibers, compared to neat PLA.

15.
Front Microbiol ; 12: 656996, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34149645

RESUMEN

The CRISPR-Cas [clustered regularly interspaced short palindromic repeats and the CRISPR-associated genes (Cas)] system provides defense mechanisms in bacteria and archaea vs. mobile genetic elements (MGEs), such as plasmids and bacteriophages, which can either be harmful or add sequences that can provide virulence or antibiotic resistance. Staphylococcus aureus is a Gram-positive bacterium that could be the etiological agent of important soft tissue infections that can lead to bacteremia and sepsis. The role of the CRISPR-Cas system in S. aureus is not completely understood since there is a lack of knowledge about it. We analyzed 716 genomes and 1 genomic island from GENOMES-NCBI and ENA-EMBL searching for the CRISPR-Cas systems and their spacer sequences (SSs). Our bioinformatic analysis shows that only 0.83% (6/716) of the analyzed genomes harbored the CRISPR-Cas system, all of them were subtype III-A, which is characterized by the presence of the cas10/csm1 gene. Analysis of SSs showed that 91% (40/44) had no match to annotated MGEs and 9% of SSs corresponded to plasmids and bacteriophages, indicating that those phages had infected those S. aureus strains. Some of those phages have been proposed as an alternative therapy in biofilm-forming or infection with S. aureus strains, but these findings indicate that such antibiotic phage strategy would be ineffective. More research about the CRISPR/Cas system is necessary for a bigger number of S. aureus strains from different sources, so additional features can be studied.

16.
Micromachines (Basel) ; 12(3)2021 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-33802204

RESUMEN

Photopolymerized microparticles are made of biocompatible hydrogels like Polyethylene Glycol Diacrylate (PEGDA) by using microfluidic devices are a good option for encapsulation, transport and retention of biological or toxic agents. Due to the different applications of these microparticles, it is important to investigate the formulation and the mechanical properties of the material of which they are made of. Therefore, in the present study, mechanical tests were carried out to determine the swelling, drying, soluble fraction, compression, cross-linking density (Mc) and mesh size (ξ) properties of different hydrogel formulations. Tests provided sufficient data to select the best formulation for the future generation of microparticles using microfluidic devices. The initial gelation times of the hydrogels formulations were estimated for their use in the photopolymerization process inside a microfluidic device. Obtained results showed a close relationship between the amount of PEGDA used in the hydrogel and its mechanical properties as well as its initial gelation time. Consequently, it is of considerable importance to know the mechanical properties of the hydrogels made in this research for their proper manipulation and application. On the other hand, the initial gelation time is crucial in photopolymerizable hydrogels and their use in continuous systems such as microfluidic devices.

17.
Polymers (Basel) ; 12(3)2020 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-32106484

RESUMEN

In this work, the suitability for the production of sustainable and lightweight materials with specific mechanical properties and potentially lower costs was studied. Agave fiber (AF), an agro-industrial waste, was used as a reinforcement and azodicarbonamide (ACA) as a chemical blowing agent (CBA) in the production of bilayer materials via rotational molding. The external layer was a composite of linear medium density polyethylene (LMDPE) with different AF contents (0-15 wt %), while the internal layer was foamed LMDPE (using 0-0.75 wt % ACA). The samples were characterized in terms of thermal, morphological and mechanical properties to obtain a complete understanding of the structure-properties relationships. Increases in the thicknesses of the parts (up to 127%) and a bulk density reduction were obtained by using ACA (0.75 wt %) and AF (15 wt %). Further, the addition of AF increased the tensile (23%) and flexural (29%) moduli compared to the neat LMDPE, but when ACA was used, lower values (75% and 56% for the tensile and flexural moduli, respectively) were obtained. Based on these results, a balance between mechanical properties and lightweight can be achieved by selecting the AF and ACA contents, as well as the performance and aesthetics properties of the rotomolded parts.

18.
Rev Med Inst Mex Seguro Soc ; 47(3): 237-42, 2009.
Artículo en Español | MEDLINE | ID: mdl-20141651

RESUMEN

In this text, we described a case of mycetoma (an osteophylic mycotic disease) found in the Tlatilco skeletal collection. The osseous lesions presented the characteristic features for the diagnosis of mycetoma. It had clinical similarities with the actual prevalence features. The topic Tlatilco culture included ecosystem characteristics and daily activities proper for this culture, showing and comparing the uncertainty of this disease nowadays.


Asunto(s)
Indígenas Norteamericanos/historia , Micetoma/historia , Historia Antigua , Humanos , México , Micetoma/patología
19.
J Immigr Minor Health ; 19(1): 155-161, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-26514152

RESUMEN

This study examined whether household income mediates the relationship between acculturation and vegetable consumption among Latino adults in the U.S. Data from the 2009 to 2010 National Health and Nutrition Examination Survey were analyzed. Vegetable consumption index was created based on the frequencies of five kinds of vegetables intake. Acculturation was measured with the degree of English language use at home. Path model with bootstrapping technique was employed for mediation analysis. A significant partial mediation relationship was identified. Greater acculturation [95 % bias corrected bootstrap confident interval (BCBCI) = (0.02, 0.33)] was associated with the higher income and in turn, greater vegetable consumption. At the same time, greater acculturation was associated with lower vegetable consumption [95 % BCBCI = (-0.88, -0.07)]. Findings regarding the income as a mediator of the acculturation-dietary behavior relationship inform unique intervention programs and policy changes to address health disparities by race/ethnicity.


Asunto(s)
Aculturación , Hispánicos o Latinos/estadística & datos numéricos , Renta/estadística & datos numéricos , Verduras , Adulto , Factores de Edad , Anciano , Dieta , Femenino , Encuestas Epidemiológicas , Humanos , Masculino , Persona de Mediana Edad , Sexo , Factores Socioeconómicos
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