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1.
Bioprocess Biosyst Eng ; 47(11): 1777-1787, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39090227

RESUMEN

The present study aims to analyze the interaction between Rhodotorula toruloides and magnetic nanoparticles and evaluate their effect on carotenoid production. The manganese ferrite nanoparticles were synthesized without chitosan (MnFe2O4) and chitosan coating (MnFe2O4-CS) by the co-precipitation method assisted by hydrothermal treatment. XRD (X-ray diffraction), Magnetometry, Dynamic Light Scattering (DLS) and FTIR (Fourier-Transform Infrared Spectroscopy), are used to characterize the magnetic nanoparticles. The crystallite size of MnFe2O4 was 16 nm for MnFe2O4 and 20 nm for MnFe2O4-CS. The magnetic saturation of MnFe2O4-CS was lower (39.6 ± 0.6 emu/g) than the same MnFe2O4 nanoparticles (42.7 ± 0.3 emu/g), which was attributed to the chitosan fraction presence. The MnFe2O4-CS FTIR spectra revealed the presence of the characteristic chitosan bands. DLS demonstrated that the average hydrodynamic diameters were 344 nm for MnFe2O4 and 167 nm for MnFe2O4-CS. A kinetic study of cell immobilization performed with their precipitation with a magnet demonstrated that interaction between magnetic nanoparticles and R. toruloides was characterized by an equilibrium time of 2 h. The adsorption isotherm models (Langmuir and Freundlich) were fitted to the experimental values. The trypan blue assay was used for cell viability assessment. The carotenoid production increased to 256.2 ± 6.1 µg/g dry mass at 2.0 mg/mL MnFe2O4-CS. The use of MnFe2O4-CS to stimulate carotenoid yeast production and the magnetic separation of biomass are promising nanobiotechnological alternatives. Magnetic cell immobilization is a perspective technique for obtaining cell metabolites.


Asunto(s)
Carotenoides , Quitosano , Compuestos Férricos , Compuestos de Manganeso , Rhodotorula , Rhodotorula/metabolismo , Quitosano/química , Compuestos de Manganeso/química , Compuestos Férricos/química , Carotenoides/química , Nanopartículas de Magnetita/química , Espectroscopía Infrarroja por Transformada de Fourier
2.
Vet Parasitol Reg Stud Reports ; 44: 100921, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37652638

RESUMEN

The knowledge of lice associated with small ruminants, especially sheep and goats, is scarce. In Mexico, there are historical reports of six species of chewing and sucking lice associated with Capra hircus and Ovis canadensis. However, the reports did not analyze the ecology of the infestations or the presence of potentially pathogenic bacteria. For this reason, the objectives of this study were i) to identify the species of lice associated with sheep and goats in three states of the Mexican Republic, ii) to characterize the infestations, and iii) to identify the presence of bacterial pathogens. From October 2019 to August 2021, six ranches with sheep and goats were sampled in the states of Hidalgo and Veracruz. Hosts were visually inspected, and lice were retrieved with forceps. The specimens were sexed and identified using morphological taxonomic keys. DNA extraction was performed individually, and a fragment of the cytochrome oxidase subunit 1 gene (COI) was amplified for the molecular identification of the specimens. Subsequently, Anaplasma, Bartonella, Ehrlichia, Mycoplasma, and Rickettsia were molecularly detected. Additionally, the infestations were characterized by calculating the prevalence and mean abundances. We collected 563 specimens of three species, Bovicola caprae, Bovicola ovis, and Linognathus africanus. The highest infestation levels were recorded for B. ovis (66.7%; 4.4) from Veracruz. Additionally, two Bartonella species were detected: Bartonella mellophagi in B. ovis and Bartonella capreoli in L. africanus. In contrast, Mycoplasma ovis was detected exclusively in one pool of B. ovis. This study provides new bacterial-ectoparasite associations and highlights the possible role of these neglected ectoparasites as vectors in the populations of sheep and goats from Mexico.


Asunto(s)
Anoplura , Bartonella , Ischnocera , Mycoplasma , Ovinos , Animales , Cabras , México/epidemiología , Bartonella/genética
3.
Saudi J Biol Sci ; 29(4): 1957-1980, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35531194

RESUMEN

The rising need for wholesome, fresh, safe and "minimally-processed" foods has led to pioneering research activities in the emerging non-thermal technology of food processing. Cold plasma is such an innovative and promising technology that offers several potential applications in the food industry. It uses the highly reactive, energetic and charged gas molecules and species to decontaminate the food and package surfaces and preserve the foods without causing thermal damage to the nutritional and quality attributes of food. Cold plasma technology showed promising results about the inactivation of pathogens in the food industry without affecting the food quality. It is highly effective for surface decontamination of fruits and vegetables, but extensive research is required before its commercial utilization. Recent patents are focused on the applications of cold plasma in food processing and preservation. However, further studies are strongly needed to scale up this technology for future commercialization and understand plasma physics for getting better results and expand the applications and benefits. This review summarizes the emerging trends of cold plasma along with its recent applications in the food industry to extend shelf life and improve the quality of food. It also gives an overview of plasma generation and principles including mechanism of action. Further, the patents based on cold plasma technology have also been highlighted comprehensively for the first time.

4.
Reumatol Clin (Engl Ed) ; 17(8): 440-446, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34625146

RESUMEN

OBJECTIVE: To determine the comorbidities associated with disability in patients with OA in Mexico (2013-2015). MATERIAL AND METHODS: A cross-sectional, retrospective and multicentre IMPACTAR study (n=7703) in Mexican patients (2013-2015). Comorbidities associated with disability were identified in 4971 patients diagnosed with OA from the IMPACTAR registry (n=7073). An adjusted logistic regression analysis was carried out by demographic, economic, clinical and medical variables. RESULTS: Mean age was 63 years; and 75% of the patients were women. Subjects with OA and presence of comorbidities are 42% more likely to develop disabilities than patients without associated comorbidity, considering age, sex, family income, OA diagnosis duration, and education level. The highest rate of people with disability (28.9%) was concentrated in Region 7, which corresponds to Mexico City. There are also significant differences between median family incomes, when the income of persons with disability is under $13 000 (IQR: 9000-16 000) Mexican pesos, compared to patients without disability. Almost half of the subjects (49.6%) reported having at least one comorbidity. Arterial hypertension was the risk factor with a statistically significant difference (32.8%) among those with disability (34.7%). CONCLUSIONS: Programs and interventions for OA patients should take into consideration comorbidity factors, being female, family income, and the region of residence as variables that may increase the possibility of developing an OA-associated disability.


Asunto(s)
Personas con Discapacidad , Osteoartritis , Comorbilidad , Estudios Transversales , Femenino , Humanos , México/epidemiología , Persona de Mediana Edad , Osteoartritis/epidemiología , Sistema de Registros , Estudios Retrospectivos
5.
Plants (Basel) ; 10(7)2021 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-34206859

RESUMEN

In Mexico, mistletoes have several applications in traditional medicine due to the great variety of compounds with biological activities that have not been characterized to date. The goals of the present study are to analyze the composition of minerals and phytochemical compounds in Mexican mistletoes Phoradendron bollanum and Viscum album subs. austriacum qualitatively and quantitatively, identify the compounds using HPLC-MS, and assess the antimicrobial potential in phytopathogenic microorganism control. Mineral content was evaluated with X-ray fluorescence. Three types of extracts were prepared: ethanol, water, and aqueous 150 mM sodium chloride solution. Characterization was carried out using qualitative tests for phytochemical compound groups, analytical methods for proteins, reducing sugars, total phenol, flavonoids quantification, and HPLC-MS for compound identification. The antimicrobial activity of mistletoe's liquid extracts was evaluated by microplate assay. K and Ca minerals were observed in both mistletoes. A qualitative test demonstrated alkaloids, carbohydrates, saponins, flavonoids, tannins, and quinones. Ethanolic extract showed flavonoids, 3845 ± 69 and 3067 ± 17.2 mg QE/g for Phoradendron bollanum and Viscum album subs. austriacum, respectively, while aqueous extracts showed a total phenol content of 65 ± 6.9 and 90 ± 1.19 mg GAE/g Phoradendron bollanum and Viscum album subs. austriacum, respectively. HPLC-MS identified largely hydroxycinnamic acids and methoxycinnamic acids. Clavibacter michiganenses was successfully inhibited by aqueous extract of both mistletoes.

6.
Sci Rep ; 11(1): 1831, 2021 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-33469087

RESUMEN

Morphological characteristics and source of adipose tissue as well as adipokines may increase cardiometabolic risk. This study aimed to explore whether adipose tissue characteristics may impact metabolic and atherogenic risks. Subcutaneous Adipose Tissue (SAT), Visceral Adipose Tissue (VAT) and peripheral blood were obtained from obese patients submitted to bariatric surgery. Adipose tissue (morphometry), plasma adiponectin, TNF-α, resistin (multiplexing) and biochemical chemistry were analyzed; as well as endothelial dysfunction (Flow Mediated Dilation, FMD) and atherogenesis (Carotid Intima Media Thickness, CIMT). Subgroups divided by adipocyte size and source were compared; as well as correlation and multivariate analysis. Sixty patients 36.6% males, aged 44 years-old, BMI 46.7 kg/m2 were included. SAT's adipocytes showed a lower range of size expandability than VAT's adipocytes. Independent from their source, larger adipocytes were associated with higher glucose, lower adiponectin and higher CIMT. Particularly, larger adipocytes from SAT were associated with higher blood pressure, lower insulin and HDL-cholesterol; and showed positive correlation with glucose, HbA1c, systolic/diastolic values, and negatively correlated with insulin and adiponectin. VAT's larger adipocytes particularly associated with lower resistin and lower FMD values. Gender and Diabetes Mellitus significantly impacted the relation of adipocyte size/source with the metabolic and atherogenic risk. Multivariable analysis suggested hypertension-resistin-HbA1c interactions associated with SAT's larger adipocytes; whereas potential insulin-adiponectin associations were observed for VAT's larger adipocytes. Adipocyte morphology and source are differentially related with cardiometabolic and atherogenic risk in population with obesity, which are potentially affected by gender and Diabetes Mellitus.


Asunto(s)
Adipocitos/metabolismo , Aterosclerosis/metabolismo , Grasa Intraabdominal/metabolismo , Obesidad/metabolismo , Grasa Subcutánea/metabolismo , Adipocitos/patología , Adulto , Aterosclerosis/patología , Femenino , Humanos , Grasa Intraabdominal/patología , Masculino , Persona de Mediana Edad , Obesidad/patología , Factores de Riesgo , Grasa Subcutánea/patología
7.
Int Microbiol ; 24(1): 37-45, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32705496

RESUMEN

Penicillin acylases (penicillin amidohydrolase, EC 3.5.1.11) are a group of enzymes with many applications within the pharmaceutical industry, and one of them is the production of semi-synthetic beta-lactam antibiotics. This enzyme is mainly produced by bacteria but also by some fungi. In the present study, the filamentous fungus Mucor griseocyanus was used to produce penicillin acylase enzyme (PGA). Its ability to express PGA enzyme in submerged fermentation process was assessed, finding that this fungal strain produces the biocatalyst of interest in an extracellular way at a level of 570 IU/L at 72 h of fermentation; in this case, a saline media using lactose as carbon source and penicillin G as inducer was employed. In addition, a DNA fragment (859 bp) of the pga from a pure Mucor griseocyanus strain was amplified, sequenced, and analyzed in silico. The partial sequence of pga identified in the fungi showed high identity percentage with penicillin G acylase sequences deposited in NCBI through BLAST, especially with the ß subunit of PGA from the Alcaligenes faecalis bacterium¸ which is a region involved in the catalytic function of this protein. Besides, the identification of domains in the penicillin G acylase sequence of Mucor griseocyanus showed three conserved regions of this protein. The bioinformatic results support the identity of the gen as penicillin G acylase. This is the first report that involves sequencing and in silico analysis of Mucor griseocyanus strain gene encoding PGA.


Asunto(s)
Proteínas Fúngicas/metabolismo , Mucor/enzimología , Penicilina Amidasa/genética , Secuencia de Aminoácidos , Secuencia de Bases , Biocatálisis , Fermentación , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Mucor/clasificación , Mucor/genética , Mucor/metabolismo , Penicilina Amidasa/química , Penicilina Amidasa/metabolismo , Filogenia , Dominios Proteicos , Alineación de Secuencia
8.
Artículo en Inglés, Español | MEDLINE | ID: mdl-32563732

RESUMEN

OBJECTIVE: To determine the comorbidities associated with disability in patients with OA in Mexico (2013-2015). MATERIAL AND METHODS: A cross-sectional, retrospective and multicentre IMPACTAR study (n=7703) in Mexican patients (2013-2015). Comorbidities associated with disability were identified in 4971 patients diagnosed with OA from the IMPACTAR registry (n=7073). An adjusted logistic regression analysis was carried out by demographic, economic, clinical and medical variables. RESULTS: Mean age was 63 years; and 75% of the patients were women. Subjects with OA and presence of comorbidities are 42% more likely to develop disabilities than patients without associated comorbidity, considering age, sex, family income, OA diagnosis duration, and education level. The highest rate of people with disability (28.9%) was concentrated in Region 7, which corresponds to Mexico City. There are also significant differences between median family incomes, when the income of persons with disability is under $13 000 (IQR: 9000-16 000) Mexican pesos, compared to patients without disability. Almost half of the subjects (49.6%) reported having at least one comorbidity. Arterial hypertension was the risk factor with a statistically significant difference (32.8%) among those with disability (34.7%). CONCLUSIONS: Programs and interventions for OA patients should take into consideration comorbidity factors, being female, family income, and the region of residence as variables that may increase the possibility of developing an OA-associated disability.

9.
PeerJ ; 7: e7866, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31637128

RESUMEN

Global climate change is expected to affect temperature and precipitation patterns worldwide, which in turn is likely to affect insect phenology, distribution and diversity. To improve our understanding of such processes, it is important to understand how insects may respond to changes in seasonality, and how these affect their activity, patterns of distribution and species richness. The tropical dry forest (TDF) is a highly seasonal ecosystem, for which two seasons are commonly described (rainy and dry) and there is a lack of information on the combined effect of both precipitation and temperature on the insect communities. In order to evaluate the seasonal patterns in the community of Cerambycidae in a TDF, historical climatic variables were obtained, and an annual sampling of the family was carried out, using three collection techniques. We found that the Cerambycidae family showed a more complex response to climate, than simply the rainy and dry season of the year. The relationship between diversity and composition of cerambycids with changes in temperature and precipitation showed four seasonal communities which were synchronized with phenological processes of the TDF. Climate change could reduce biodiversity, causing seasonal patterns to lose complexity, either because the climatic characteristics of a season disappear and/or because the duration of a season expands, these changes will modify the ecological processes of the TDF, since they would generate changes in the flora and fauna associated with the different seasons.

10.
Med. interna Méx ; 35(3): 389-396, may.-jun. 2019. graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1154812

RESUMEN

Resumen: La adiponectina es una hormona sensibilizadora a la insulina y antiinflamatoria secretada por el tejido adiposo que tiene un inmenso potencial como objetivo terapéutico de una multitud de enfermedades relacionadas con la obesidad, incluida la diabetes tipo 2, la aterosclerosis y las enfermedades cardiovasculares. El gen de la adiponectina se encuentra en el cromosoma 3q27, un locus de susceptibilidad para la diabetes tipo 2 y los trastornos metabólicos. El aumento de las concentraciones circulantes de adiponectina se asocia con reducción del síndrome metabólico y las reducciones son muy predictivas del riesgo de diabetes. Se han hecho grandes esfuerzos para comprender cómo pueden elevarse las concentraciones de adiponectina. El complejo procesamiento postraduccional y la secreción de adiponectina proporciona un área rica en la que puede desarrollarse la manipulación farmacológica para aumentar las concentraciones de adiponectina en humanos. Las concentraciones circulantes de adiponectina se incrementan con muchos fármacos de administración común, como las estatinas, los inhibidores de la enzima convertidora de angiotensina y las tiazolidinedionas, lo que da una oportunidad importante para conocer los mecanismos que subyacen a sus efectos. Esta revisión describe la relación que existe entre la obesidad, la diabetes tipo 2 y la adiponectina, se discuten las funciones específicas en los tejidos y las células de la adiponectina, con insistencia en la regulación de las vías de señalización de adiponectina, así como las posibles vías de señalización implicadas en la regulación metabólica.


Abstract: Adiponectin is an insulin-sensitizing and anti-inflammatory fat cell hormone that has immense potential as a therapeutic target for a multitude of obesity-associated diseases including type 2 diabetes, atherosclerosis and cardiovascular diseases. The adiponectin gene is located in chromosome 3q27, a susceptibility locus for type 2 diabetes and metabolic disorders. Increased circulating levels of adiponectin are associated with improvement in the metabolic syndrome and reductions are strongly predictive of diabetes risk. Extensive efforts have been made to understand how adiponectin levels can be elevated. The complex posttranslational processing and secretion of adiponectin provides a rich area where pharmacologic manipulation may be developed to increase adiponectin levels in humans. Circulating adiponectin levels are increased by many commonly used drugs, such as statins, angiotensin converting enzyme inhibitors, and thiazolidinediones providing an important opportunity to gain insight into the mechanisms underlying their effects. This review describes the relationship among obesity, type 2 diabetes and adiponectin, we discuss the specific functions in tissues and cells of adiponectin, with emphasis on the regulation of adiponectin signaling pathways, as well as possible pathways of signaling involved in metabolic regulation.

11.
Compr Rev Food Sci Food Saf ; 18(4): 1039-1051, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33336997

RESUMEN

Traditional fermented foods where lactic acid bacteria (LAB) are present have been associated with beneficial effects on human health, and some of those benefits are related to protein-derived products. Peptides produced by LAB have attracted the interest of food industries because of their diverse applications. These peptides include ribosomally produced (bacteriocins) and protein hydrolysates by-products (bioactive peptides), which can participate as natural preservatives and nutraceuticals, respectively. It is essential to understand the biochemical pathways and the effect of growth conditions for the production of bioactive peptides and bacteriocins by LAB, in order to suggest strategies for optimization. LAB is an important food-grade expression system that can be used in the simultaneous production of peptide-based products for the food, animal, cosmetic, and pharmaceutical industries. This review describes the multifunctional proteinaceous compounds generated by LAB metabolism and discusses a strategy to use a single-step production process, using an alternative protein-based media. This strategy will provide economic advantages in fermentation processes and will also provide an environmental alternative to industrial waste valorization. New technologies that can be used to improve production and bioactivity of LAB-derived peptides are also analyzed.

12.
Arch. latinoam. nutr ; Arch. latinoam. nutr;68(3): 268-279, sept. 2018. ilus, tab
Artículo en Inglés | LIVECS, LILACS | ID: biblio-1016085

RESUMEN

Lemon balm (Melissa officinalis) is a plant in the family of Lamiaceae. In Mexican traditional medicine it is used to alleviate gastrointestinal and hepatic problems. Studies carried out mainly in ethanolic and methanolic extracts, have revealed the presence of diverse compounds to which those medicinal properties are attributed. The objective of this research work was to extract in aqueous solution the antioxidants present in lemon balm and identify them through HPLC-MS. A Box-Behnken design was applied to determine the physical conditions of antioxidant extraction, where the analyzed variables were time, temperature and sample quantity. The antioxidant activity was determined through methodologies of DPPH*, FRAP and total phenolics. The aqueous solution with the highest antioxidant activity was analyzed through HPLC-MS. The results showed that the interaction temperature-time has a positive influence on the liberation of antioxidants. The best condition for a conventional extraction of antioxidants was 90°C, 15 min and 2 g of sample. Higher correlations were observed at r2>0.6 between determined antioxidant activity by DPPH* (or FRAP) vs Total phenolics; this would indicate that such activity could be attributed to phenolic compounds whose presence was confirmed through an analysis by HPLC-MS(AU)


El toronjil (Melissa officinalis) es una planta de la familia Lamiaceae. En la medicina tradicional mexicana es utilizado para aliviar problemas gastrointestinales y hepáticos. Algunos estudios realizados con extractos etanólicos y metanólicos de dicha planta, han revelado la presencia de diversos compuestos a los que se les atribuye sus propiedades medicinales. El objetivo de esta investigación fue extraer en solución acuosa los antioxidantes presentes en el toronjil e identificarlos a través de HPLC-MS. Para ello, se aplicó un diseño de experimentos Box-Behnken a fin de determinar las condiciones físicas de extracción de antioxidantes; las variables analizadas fueron tiempo, temperatura y cantidad de muestra. La actividad antioxidante fue determinada a través de las metodologías de DPPH*, FRAP y fenoles totales. El extracto acuoso con la mayor actividad antioxidante fue analizado mediante HPLCMS. Los resultados mostraron que la interacción tiempotemperatura tuvo una influencia positiva en la liberación de antioxidantes. La mejor condición para la extracción de antioxidantes presentes en el toronjil fue 90°C, 15 min y 2 g de muestra. Correlaciones superiores a r2>0.6 fueron determinadas entre la actividad antioxidante medida por DPPH* (o FRAP) vs Fenoles totales; esto podría indicar que la actividad antioxidante encontrada podría atribuirse a compuestos de tipo fenólico cuya presencia fue confirmada por el análisis en HPLC-MS(AU)


Asunto(s)
Humanos , Masculino , Femenino , Investigación Homeopática Básica , Melissa , Antioxidantes , Terapéutica , Enfermedades Gastrointestinales
13.
Med. interna Méx ; 34(3): 443-476, may.-jun. 2018. tab, graf
Artículo en Español | LILACS | ID: biblio-976088

RESUMEN

Resumen La osteoartritis es una enfermedad articular crónica degenerativa, es la afección articular observada con más frecuencia en la población adulta y una de las principales causas de discapacidad en todo el mundo, por lo que es de importancia el diagnóstico y tratamiento en las fases tempranas de la enfermedad. En la actualidad los nuevos tratamientos, además de aliviar el dolor, pueden disminuir la limitación funcional y modificar el curso de la enfermedad. El objetivo de este artículo es actualizar la evidencia acerca del diagnóstico y de las nuevas formas de tratamiento de la osteoartritis, así como evaluar los cambios en la evidencia que ha habido en relación con la guía anterior. Para la elaboración de la guía motivo de esta reunión, se contó con la participación de especialistas en Medicina Interna, Reumatología, Ortopedia y Rehabilitación física, un bibliotecario y un experto en metodología; se realizó una búsqueda extensa en PubMed y en otros sitios web especializados. Se estableció una serie de recomendaciones y niveles de evidencia basados en la bibliografía consultada. Se concluye que la osteoartritis es una enfermead compleja que implica múltiples factores de riesgo, por lo que es importante tomar en cuenta que el tratamiento es multidisciplinario y consta de un enfoque no farmacológico y uno farmacológico; sin embargo, es necesario crear una cultura preventiva de la osteoartritis en los médicos tratantes, en la que se eduque y se dé información al paciente para evitar que la enfermedad progrese.


Abstract Osteoarthritis, a chronic degenerative joint disease, is the joint condition most frequently observed in the adult population; is one of the leading causes of disability worldwide. Therefore, it is important the diagnosis and treatment in the early stages of the disease. Currently new therapies, in addition to relieving pain, can reduce functional limitation and modify the course of the disease. The objective of this article is to update the evidence on diagnosis and new forms of osteoarthritis treatment, as well as to evaluate the changes in the evidence that has been in relation to the previous guide. For the elaboration of the guide, there was participation of specialists (Internal Medicine, Rheumatology, Orthopedics and Physical Rehabilitation), a librarian and an expert in methodology; an extensive search was carried out in PubMed and other specialized websites. A series of recommendations and levels of evidence were established based on the bibliography consulted. Concluding that osteoarthritis is a complex pathology involving multiple risk factors, it is important to consider that the treatment is multidisciplinary and consists of a non-pharmacological approach and a pharmacological treatment; however, it is necessary to create a preventive culture on osteoarthritis in treating doctors, in which the patient is educated and given information to prevent the disease from progressing.

14.
Bioresour Technol ; 239: 430-436, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28538199

RESUMEN

Three alternatives for bioethanol production from pretreated mango stem bark after maceration (MSBAM) were evaluated as a biorefinery component for the mango agroindustry. These included separate hydrolysis and fermentation (SHF), simultaneous saccharification and fermentation (SSF), and pre-saccharification followed by simultaneous saccharification and fermentation (PSSF). The effects on ethanol concentration, yield and productivity of pretreated MSBAM solids loading, Tween 20 addition, and temperature were used for process comparisons. The highest yields for the SHF, SSF, and PSSF process alternatives were 58.8, 81.6, and 84.5%, respectively. Since saccharification and fermentation are carried out in the same vessel in the SSF alternative, and no significant SSF and PSSF differences in ethanol concentration were observed, SSF is recommended as the best process configuration.


Asunto(s)
Biocombustibles , Mangifera , Etanol , Fermentación , Hidrólisis , Temperatura
15.
Bioprocess Biosyst Eng ; 40(1): 9-22, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27534411

RESUMEN

In the present study, Trichoderma reesei cellulase was covalently immobilized on chitosan-coated magnetic nanoparticles using glutaraldehyde as a coupling agent. The average diameter of magnetic nanoparticles before and after enzyme immobilization was about 8 and 10 nm, respectively. The immobilized enzyme retained about 37 % of its initial activity, and also showed better thermal and storage stability than free enzyme. Immobilized cellulase retained about 80 % of its activity after 15 cycles of carboxymethylcellulose hydrolysis and was easily separated with the application of an external magnetic field. However, in this reaction, K m was increased eight times. The immobilized enzyme was able to hydrolyze lignocellulosic material from Agave atrovirens leaves with yield close to the amount detected with free enzyme and it was re-used in vegetal material conversion up to four cycles with 50 % of activity decrease. This provides an opportunity to reduce the enzyme consumption during lignocellulosic material saccharification for bioethanol production.


Asunto(s)
Agave/química , Biomasa , Celulasas/química , Quitosano/química , Proteínas Fúngicas/química , Lignina/química , Nanopartículas de Magnetita/química , Trichoderma/enzimología , Enzimas Inmovilizadas/química , Hidrólisis
16.
Zootaxa ; 4208(1): zootaxa.4208.1.5, 2016 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-27988540

RESUMEN

Two new species of the genus Phaea Newman are described from Mexico. Phaea chemsaki sp. nov. from Chiapas, and P. parallela sp. nov. from Morelos. The descriptions are supplemented with photographs.


Asunto(s)
Escarabajos/anatomía & histología , Escarabajos/clasificación , Animales , Femenino , Masculino , México , Especificidad de la Especie
17.
Med Sci Monit ; 21: 1194-9, 2015 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-25913248

RESUMEN

BACKGROUND: Alpha1 anti-trypsin (α1-AT), a serine protease inhibitor synthesized in the liver, is a major circulating antiprotease that provides defense against proteolytic damage in several tissues. Its deficiency is associated with airflow obstruction. The present study aimed to explore the role of α1-AT as a biomarker of airflow performance in chronic liver disease (CLD). MATERIAL/METHODS: Serum α1-AT levels and lung function (spirometry) were evaluated in non-primary α1-AT-deficient, alcoholic CLD patients without evident respiratory limitations. RESULTS: Thirty-four patients with airflow obstruction (n=11), airflow restriction (n=12), and normal airflow (n=11, age-matched controls) were eligible. α1-AT was decreased in the airflow obstruction group. ROC-cutoff α1-AT=24 mg/dL effectively discriminated airflow obstruction (AUC=0.687) and was associated with a 10-fold higher risk (p=0.0007). CONCLUSIONS: Lower α1-AT increased the risk of airflow obstruction in CLD patients without primary α1-AT deficiency.


Asunto(s)
Hepatopatías Alcohólicas/sangre , Hepatopatías Alcohólicas/fisiopatología , Enfermedad Pulmonar Obstructiva Crónica/etiología , Deficiencia de alfa 1-Antitripsina/sangre , Deficiencia de alfa 1-Antitripsina/fisiopatología , alfa 1-Antitripsina/sangre , Adulto , Anciano , Biomarcadores/sangre , Estudios de Casos y Controles , Estudios Transversales , Femenino , Humanos , Hepatopatías Alcohólicas/complicaciones , Enfermedades Pulmonares Obstructivas/sangre , Enfermedades Pulmonares Obstructivas/etiología , Enfermedades Pulmonares Obstructivas/fisiopatología , Masculino , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/sangre , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Factores de Riesgo , Espirometría , Deficiencia de alfa 1-Antitripsina/complicaciones
18.
Cir Cir ; 82(1): 109-18, 2014.
Artículo en Español | MEDLINE | ID: mdl-25510798

RESUMEN

Increase in the incidence of invasive aspergillosis has represented a difficult problem for management of patients with this infection due to its high rate of mortality, limited knowledge concerning its diagnosis, and therapeutic practice. The difficulty in management of patients with aspergillosis initiates with detection of the fungus in the specimens of immunosuppressed patients infected with Aspergillus fumigatus; in addition, difficulty exists in terms of the development of resistance to antifungals as a consequence of their indiscriminate use in prophylactic and therapeutic practice and to ignorance concerning the epidemiological data of aspergillosis. With the aim of resolving these problems, molecular markers is employed at present with specific and accurate results. However, in Mexico, the use of molecular markers has not yet been implemented in the routine of intrahospital laboratories; despite the fact that these molecular markers has been widely referred in the literature, it is necessary for it to validated and standardized to ensure that the results obtained in any laboratory would be reliable and comparable. In the present review, we present an update on the usefulness of molecular markers in accurate identification of A. fumigatus, detection of resistance to antifugal triazoles, and epidemiological studies for establishing the necessary measures for prevention and control of aspergillosis.


El incremento en la incidencia de la aspergilosis invasora representa un grave problema para el tratamiento de pacientes con esta micosis, debido a su elevada tasa de mortalidad por deficiencias diagnósticas y terapéuticas. Éstas se han atribuido a la dificultad para detectar Aspergillus fumigatus, principal agente etiológico de esta micosis, en las muestras biológicas de pacientes inmunosuprimidos, que son los principales afectados por el hongo; además por la resistencia a los antifúngicos como consecuencia del uso incontrolado de éstos, a nivel profiláctico y terapéutico, y el desconocimiento de aspectos epidemiológicos de la aspergilosis. En la actualidad, para superar estas limitaciones se han empleado marcadores moleculares. En México su uso aún no está implementado en la rutina de los laboratorios intrahospitalarios, porque a pesar de que se han reportado ampliamente en la bibliografía, hace falta validarlos y estandarizarlos para asegurar que los resultados que se obtengan en cualquier laboratorio sean confiables y comparables. En este trabajo se presenta una revisión actualizada de la utilidad de los marcadores moleculares en la identificación certera de A. fumigatus en la detección de resistencia a los antifúngicos triazólicos y en estudios epidemiológicos para establecer las medidas necesarias en la prevención y control de la aspergilosis.


Asunto(s)
Aspergilosis/sangre , ADN de Hongos/sangre , Fungemia/sangre , Técnicas de Diagnóstico Molecular/métodos , Animales , Antifúngicos/uso terapéutico , Aspergilosis/diagnóstico , Aspergilosis/tratamiento farmacológico , Aspergilosis/epidemiología , Aspergillus fumigatus/efectos de los fármacos , Aspergillus fumigatus/genética , Aspergillus fumigatus/inmunología , Monitoreo de Drogas , Farmacorresistencia Fúngica Múltiple/genética , Fungemia/diagnóstico , Fungemia/tratamiento farmacológico , Amplificación de Genes , Genes Fúngicos , Infecciones por VIH/complicaciones , Infecciones por VIH/inmunología , Humanos , México/epidemiología , Ratones , Técnicas de Tipificación Micológica , Neoplasias/complicaciones , Neoplasias/inmunología , Infecciones Oportunistas/sangre , Infecciones Oportunistas/diagnóstico , Infecciones Oportunistas/tratamiento farmacológico
19.
Nutr Hosp ; 29(3): 513-8, 2014 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-24558992

RESUMEN

OBJECTIVE: To assess the adequacy of predictive equations for estimation of energy expenditure (EE), compared with the EE using indirect calorimetry in a sample of Brazilian and Spanish women with excess body weight. METHODS: It is a cross-sectional study with 92 obese adult women [26 Brazilian -G1- and 66 Spanish - G2- (aged 20-50)]. Weight and height were evaluated during fasting for the calculation of body mass index and predictive equations. EE was evaluated using the open-circuit indirect calorimetry with respiratory hood. RESULTS: In G1 and G2, it was found that the estimates obtained by Harris-Benedict, Shofield, FAO/WHO/ ONU and Henry & Rees did not differ from EE using indirect calorimetry, which presented higher values than the equations proposed by Owen, Mifflin-St Jeor and Oxford. For G1 and G2 the predictive equation closest to the value obtained by the indirect calorimetry was the FAO/WHO/ONU (7.9% and 0.46% underestimation, respectively), followed by Harris-Benedict (8.6% and 1.5% underestimation, respectively). CONCLUSION: The equations proposed by FAO/WHO/ ONU, Harris-Benedict, Shofield and Henry & Rees were adequate to estimate the EE in a sample of Brazilian and Spanish women with excess body weight. The other equations underestimated the EE.


Objetivo: Evaluar la adecuación de las ecuaciones de predicción para la estimación del gasto energético (GE), en comparación con el GE medido por calorimetría indirecta en una muestra de mujeres brasileñas y españolas con exceso de peso corporal. Métodos: Se trata de un estudio transversal con 92 mujeres adultas obesas [26 brasileñas ­G1­ y 66 españolas ­G2­ (20-50 años)]. Se evaluó el peso y la talla durante el ayuno para el cálculo del índice de masa corporal y las ecuaciones de predicción. Se evaluó el GE usando la calorimetría indirecta de circuito abierto con campana respiratoria. Resultados: En G1 y G2, se encontró que las estimaciones obtenidas por Harris-Benedict, Shofield, FAO/OMS/ ONU y Henry y Rees no difieren del GE estimado por calorimetría indirecta, la cual presentó valores más altos que las ecuaciones propuestas por Owen Mifflin -St Jeor y Oxford. Para G1 y G2 la ecuación predictiva que presentó valores más cercanos al valor obtenido por la calorimetría indirecta fue la FAO/OMS/ONU (7,9% y 0,46% subestimación, respectivamente), seguido por Harris-Benedict (8,6% y 1,5% subestimación, respectivamente). Conclusión: Las ecuaciones propuestas por la FAO/ OMS/ONU, Harris-Benedict, Shofield y Henry & Rees fueron adecuadas para estimar el GE en una muestra de mujeres brasileñas y españolas con exceso de peso corporal. Las otras ecuaciones subestimaron el GE.


Asunto(s)
Algoritmos , Metabolismo Energético , Obesidad/fisiopatología , Sobrepeso/fisiopatología , Adulto , Brasil , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , España , Adulto Joven
20.
J Biophys ; 2013: 913792, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23533398

RESUMEN

Ghrelin is a growth hormone (GH) secretagogue (GHS) and GHRP-6 is a synthetic peptide analogue; both act through the GHS receptor. GH secretion depends directly on the intracellular concentration of Ca(2+); this is determined from the intracellular reserves and by the entrance of Ca(2+) through the voltage-dependent calcium channels, which are activated by the membrane depolarization. Membrane potential is mainly determined by K(+) channels. In the present work, we investigated the effect of ghrelin (10 nM) or GHRP-6 (100 nM) for 96 h on functional expression of voltage-dependent K(+) channels in rat somatotropes: GC cell line. Physiological patch-clamp whole-cell recording was used to register the K(+) currents. With Cd(2+) (1 mM) and tetrodotoxin (1 µ m) in the bath solution recording, three types of currents were characterized on the basis of their biophysical and pharmacological properties. GC cells showed a K(+) current with a transitory component (I A) sensitive to 4-aminopyridine, which represents ~40% of the total outgoing current; a sustained component named delayed rectifier (I K), sensitive to tetraethylammonium; and a third type of K(+) current was recorded at potentials more negative than -80 mV, permitting the entrance of K(+) named inward rectifier (KIR). Chronic treatment with ghrelin or GHRP-6 did not modify the functional expression of K(+) channels, without significant changes (P < 0.05) in the amplitudes of the three currents observed; in addition, there were no modifications in their biophysical properties and kinetic activation or inactivation.

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