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1.
Chem Rev ; 124(13): 8233-8306, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38885684

RESUMEN

Interest in energy-to-X and X-to-energy (where X represents green hydrogen, carbon-based fuels, or ammonia) technologies has expanded the field of electrochemical conversion and storage. Solid oxide electrochemical cells (SOCs) are among the most promising technologies for these processes. Their unmatched conversion efficiencies result from favorable thermodynamics and kinetics at elevated operating temperatures (400-900 °C). These solid-state electrochemical systems exhibit flexibility in reversible operation between fuel cell and electrolysis modes and can efficiently utilize a variety of fuels. However, electrocatalytic materials at SOC electrodes remain nonoptimal for facilitating reversible operation and fuel flexibility. In this Review, we explore the diverse range of electrocatalytic materials utilized in oxygen-ion-conducting SOCs (O-SOCs) and proton-conducting SOCs (H-SOCs). We examine their electrochemical activity as a function of composition and structure across different electrochemical reactions to highlight characteristics that lead to optimal catalytic performance. Catalyst deactivation mechanisms under different operating conditions are discussed to assess the bottlenecks in performance. We conclude by providing guidelines for evaluating the electrochemical performance of electrode catalysts in SOCs and for designing effective catalysts to achieve flexibility in fuel usage and mode of operation.

2.
Angew Chem Int Ed Engl ; 62(24): e202302887, 2023 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-37067387

RESUMEN

Direct air capture (DAC) processes for extraction of CO2 from ambient air are unique among chemical processes in that they operate outdoors with minimal feed pretreatments. Here, the impact of humidity on the oxidative degradation of a prototypical solid supported amine sorbent, poly(ethylenimine) (PEI) supported on Al2 O3 , is explored in detail. By combining CO2 adsorption measurements, oxidative degradation rates, elemental analyses, solid-state NMR and in situ IR spectroscopic analysis in conjunction with 18 O labeling of water, a comprehensive picture of sorbent oxidation is achieved under accelerated conditions. We demonstrated that the presence of water vapor can play an important role in accelerating the degradation reactions. From the study we inferred the identity and kinetics of formation of the major oxidative products, and the role(s) of humidity. Our data are consistent with a radical mediated autooxidative degradation mechanism.

3.
Mol Biol Rep ; 49(10): 9509-9520, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35980532

RESUMEN

BACKGROUND: About 5-10% of breast cancer cases are related to genetic and hereditary factors. The application of Next Generation Sequencing (NGS) in oncology has allowed the identification of genetic variants present in several genes related to the increased risk of breast cancer. This study aimed to determine the frequency of germline genetic variants in patients with a family and/or personal history of breast cancer. METHODS: An analysis of positive reports from NGS panels was carried out in female individuals with a personal and/or family history of breast cancer, present in the database of a private laboratory in Brazil. RESULTS: From about 2000 reports, 183 individuals presented 219 different germline genetic variants. The genes with the highest number of variants were BRCA2 (16.0%), ATM (15.0%) and BRCA1 (12.8%). Among the variants found, 78 were either pathogenic or probably pathogenic, accounting for 35% of all variants discovered. The gene with the highest proportion of pathogenic/probably pathogenic variants was TP53 (80%) and the most frequent pathogenic variant was also reported in this gene (c.1010G > A p.(Arg337His)). Furthermore, the study obtained a high proportion of variants of uncertain significance (VUS) (65%) and approximately 32% of the variants found were in genes of moderate penetrance. CONCLUSIONS: Our results could improve the risk estimation and clinical follow-up of Brazilian patients with a history of breast cancer.


Asunto(s)
Neoplasias de la Mama , Proteína BRCA1/genética , Brasil/epidemiología , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Femenino , Genes BRCA2 , Predisposición Genética a la Enfermedad , Células Germinativas , Mutación de Línea Germinal/genética , Humanos
4.
J Am Chem Soc ; 140(26): 8128-8137, 2018 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-29847727

RESUMEN

Oxygen electrocatalysis plays a critical role in the efficiency of important energy conversion and storage systems. While many efforts have focused on designing efficient electrocatalysts for these processes, optimal catalysts that are inexpensive, active, selective, and stable are still being searched. Nonstoichiometric, mixed-metal oxides present a promising group of electrocatalysts for these processes due to the versatility of the surface composition and fast oxygen conducting properties. Herein, we demonstrate, using a combination of theoretical and experimental studies, the ability to develop design principles that can be used to engineer oxygen electrocatalysis activity of layered, mixed ionic-electronic conducting Ruddlesden-Popper (R-P) oxides. We show that a density function theory (DFT) derived descriptor, O2 binding energy on a surface oxygen vacancy, can be effective in identifying efficient R-P oxide structures for oxygen reduction reaction (ORR). Using a controlled synthesis method, well-defined nanostructures of R-P oxides are obtained, which along with thermochemical and electrochemical activity studies are used to validate the design principles. This has led to the identification of a highly active ORR electrocatalyst, nanostructured Co-doped lanthanum nickelate oxide, which when incorporated in solid oxide fuel cell cathodes significantly enhances the performance at intermediate temperatures (∼550 °C), while maintaining long-term stability. The reported findings demonstrate the effectiveness of the developed design principles to engineer mixed ionic-electronic conducting oxides for efficient oxygen electrocatalysis, and the potential of nanostructured Co-doped lanthanum nickelate oxides as promising catalysts for oxygen electrocatalysis.

5.
J Transl Med ; 16(1): 240, 2018 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-30165858

RESUMEN

BACKGROUND: Individuals with arterial hypertension often have an autonomic nervous system (ANS) imbalance with predominance of sympathetic ANS. This predominance can lead to injury of several organs affecting its functioning. There is evidence that performing high intensity resistance training (RT) with heavier loads and a lower number of repetitions results in lower cardiovascular stress when compared with lighter loads and a higher number of repetitions. However, the effects of different protocols of RT in autonomic modulation are not known. Therefore, the aim of the study was to analyze and compare the effects of different protocols of high intensity of effort RT on autonomic cardiac modulation of hypertensive women. METHODS: A randomized crossover design clinical trial was conducted with 15 postmenopausal hypertensive women who underwent a control session and two high intensity RT protocols involving 6 and 15 repetition maximum (RM). Heart rate variability (HRV), systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR) and double product (DP) were collected pre, immediately post, 1 h post, and 24 h post each protocol. Repeated-measures ANOVA were used. RESULTS: SBP was higher for 6RM than control immediately after session (p < 0.05). There were no differences for DBP among protocols (p ≥ 0.05). HR was higher for 15RM than 6RM and control immediately after and 1 h after session (p ≤ 0.05). DP values for 15RM were significantly higher than 6RM and control immediately after the session and remained higher than control 1 h after session (p ≤ 0.05). The indices that compose HRV (rMSSD) were lower after 15RM than 6RM and control (p ≥ 0.05). The parameters of parasympathetic activity (HF) were decreased and sympathetic (LF) activity was increased for 15RM when compared to the 6RM and control session immediately after the exercise session (p ≤ 0.05). CONCLUSION: Performing high intensity RT with lower loads and a higher number of repetitions seems to promote acute increases in sympathetic ANS activity, which may be related to cardiovascular stress. On the other hand, heavier load and lower repetition RT did not significantly impact upon autonomic modulation when compared to a control session.


Asunto(s)
Sistema Nervioso Autónomo , Enfermedades Cardiovasculares/terapia , Ejercicio Físico/fisiología , Hipertensión/terapia , Posmenopausia , Entrenamiento de Fuerza , Anciano , Antropometría , Presión Sanguínea , Sistema Cardiovascular , Estudios Cruzados , Diástole , Femenino , Corazón/fisiología , Frecuencia Cardíaca , Humanos , Persona de Mediana Edad , Sístole
6.
Eur J Appl Physiol ; 117(6): 1257-1265, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28424870

RESUMEN

PURPOSE: To compare the increases in upper- and lower-body muscle strength in premenopausal women performing resistance training (RT) alone or alongside concurrent high-intensity interval training (CT). METHODS: Sixteen women (26-40 years) were randomly assigned into two groups that performed either RT or CT. Both groups performed the same RT program; however, CT performed additional high-intensity interval training (HIIT) on a bicycle ergometer before RT. The study lasted 8 weeks and the participants were tested for ten repetition maximum (10RM) load in elbow flexion (barbell biceps curl) and knee extension exercises pre- and post-intervention. RT was performed with 10-12 repetitions to self-determined repetition maximum in the first four weeks and then progressed to 8-10. During CT, HIIT was performed before RT with six 1-min bouts at 7-8 of perceived subjective exertion (RPE) and then progressed to eight bouts at 9-10 RPE. RESULTS: Analysis of variance revealed significant increases in upper and lower body strength for both the RT and CT groups. Biceps barbell curl 10RM load increased from 12.9 ± 3.2 kg to 14 ± 1.5 kg in CT (p < 0.05) and from 13 ± 1.8 kg to 15.9 ± 2.5 kg in RT (p < 0.05), with no significant between-groups differences. Knee extension 10RM increase from 31.9 ± 11.6 kg to 37.5 ± 8.5 kg for CT (p < 0.05) and from 30.6 ± 8.6 kg to 41.2 ± 7.4 kg for RT (p < 0.05). CONCLUSION: In conclusion, performing HIIT on a cycle ergometer before resistance training does not seem to impair muscle strength increases in the knee extensors or elbow flexors of pre-menopausal women. This information should be considered when prescribing exercise sessions, since both activities may be combined without negative effects in muscle strength.


Asunto(s)
Entrenamiento de Intervalos de Alta Intensidad/métodos , Fuerza Muscular , Entrenamiento de Fuerza/métodos , Adulto , Femenino , Entrenamiento de Intervalos de Alta Intensidad/efectos adversos , Humanos , Músculo Esquelético/fisiología , Premenopausia/fisiología , Entrenamiento de Fuerza/efectos adversos
7.
J Cardiovasc Electrophysiol ; 26(12): 1364-9, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26331943

RESUMEN

INTRODUCTION: The anti-atrial fibrillation (AF) effects of GS-458967 (GS-967), a selective, potent inhibitor of cardiac late Na(+) current (I(Na)), were evaluated in a novel model of AF induction that does not require electrical stimuli. METHODS AND RESULTS: In 6 closed-chest anesthetized pigs, AF was induced by intrapericardial acetylcholine (1 mL of 100 mM solution) followed within 1 minute by epinephrine (20 µg/kg, i.v., bolus over 1 min). Effects of GS-967 (0.4 mg/kg, i.v., infused over 30 min) on inducibility and duration of AF were analyzed. Administration of acetylcholine followed by epinephrine elicited spontaneous AF that persisted for 12.03 ± 1.22 minutes (mean ± SEM) in all 6 pigs. Following GS-967, AF did not occur in 5 of 6 pigs when plasma concentration was 383 ± 150 nM. In the single animal in which AF could still be induced, the arrhythmia lasted 6.3 minutes. Partial return of AF inducibility occurred in 2 of 6 animals at 90 minutes, when plasma concentration of GS-967 was 228 ± 35 nM. GS-967 reduced the QT interval (P = 0.004), consistent with cardiac late I(Na) inhibition, but did not affect heart rate, mean arterial pressure, QRS duration, or PR interval. Epinephrine infusion alone, tested in a separate group (N = 6), did not provoke AF. CONCLUSION: Selective cardiac late I(Na) inhibition with GS-967 suppresses spontaneous induction of AF in a novel model that does not require provocative electrical stimuli. Because this mode of action has only a mild on effect on contractility, it offers an advantage over contemporary anti-AF agents, which can have negative inotropic actions.


Asunto(s)
Antiarrítmicos/uso terapéutico , Fibrilación Atrial/prevención & control , Enfermedades del Sistema Nervioso Autónomo/prevención & control , Piridinas/uso terapéutico , Bloqueadores de los Canales de Sodio/uso terapéutico , Triazoles/uso terapéutico , Acetilcolina , Animales , Antiarrítmicos/farmacocinética , Presión Arterial/efectos de los fármacos , Fibrilación Atrial/inducido químicamente , Fibrilación Atrial/fisiopatología , Enfermedades del Sistema Nervioso Autónomo/complicaciones , Enfermedades del Sistema Nervioso Autónomo/fisiopatología , Estimulación Eléctrica , Electrocardiografía/efectos de los fármacos , Epinefrina , Frecuencia Cardíaca/efectos de los fármacos , Masculino , Piridinas/farmacocinética , Bloqueadores de los Canales de Sodio/farmacocinética , Sus scrofa , Porcinos , Triazoles/farmacocinética
8.
Genet Res (Camb) ; 96: e002, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24594201

RESUMEN

Lung cancer is the leading global cause of cancer-related mortality. Inter-individual variability in treatment response and prognosis has been associated with genetic polymorphisms in specific genes: EGFR, KRAS, BRAF, PTEN and TTF-1. Somatic mutations in EGFR and KRAS genes are reported at rates of 15-40% in non-small cell lung cancer (NSCLC) in ethnically diverse populations. BRAF and PTEN are commonly mutated genes in various cancer types, including NSCLC, with PTEN mutations exerting an effect on the therapeutic response of EGFR/AKT/PI3K pathway inhibitors. TTF-1 is expressed in approximately 80% of lung adenocarcinomas and its positivity correlates with higher prevalence of EGFR mutation in this cancer type. To determine molecular markers for lung cancer in Brazilian patients, the rate of the predominant EGFR, KRAS, BRAF and PTEN mutations, as well as TTF-1 expression, was assessed in 88 Brazilian NSCLC patients. EGFR exon 19 deletions (del746-750) were detected in 3/88 (3·4%) patients. Activating KRAS mutations in codons 12 and 61 were noted in five (5·7%) and two (2·3%) patients, respectively. None of the common somatic mutations were detected in either the BRAF or PTEN genes. TTF-1 was overexpressed in 40·7% of squamous-cell carcinoma (SCC). Our findings add to a growing body of data that highlights the genetic heterogeneity of the abnormal EGFR pathway in lung cancer among ethnically diverse populations.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Receptores ErbB/genética , Neoplasias Pulmonares/genética , Mutación/genética , Fosfohidrolasa PTEN/genética , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas/genética , Proteínas ras/genética , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patología , Adulto , Anciano , Anciano de 80 o más Años , Brasil , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Estudios de Casos y Controles , Femenino , Predisposición Genética a la Enfermedad , Humanos , Técnicas para Inmunoenzimas , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Reacción en Cadena de la Polimerasa , Pronóstico , Proteínas Proto-Oncogénicas p21(ras) , Factores de Transcripción
9.
Clin Nutr ; 43(1): 95-110, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38016244

RESUMEN

AIMS: This scoping review aimed to identify, explore, and map the objectives, methodological aspects, and results of studies that used ultrasound (US) to assess skeletal muscle (SM) in critically ill patients. METHODS: A scoping review was conducted according to the Joanna Briggs Institute's methodology. All studies that evaluated SM parameters from the US in patients admitted to the intensive care unit (ICU) were considered eligible. We categorized muscle thickness and cross-sectional area as parameters for assessing SM quantity, while echogenicity, fascicle length, and pennation angle analysis were used to evaluate muscle "quality" (composition/architecture). A literature search was conducted using four databases for articles published until December 2022. Independent reviewers selected the studies and extracted data. Descriptive statistics were calculated to present the results. RESULTS: A total of 107 studies were included, the majority of which were prospective cohort studies (59.8 %) conducted in general ICUs (49.5 %). The most frequent objective of the studies was to evaluate SM quantity depletion during the ICU stay (25.2 %), followed by determining whether a specific intervention would modify SM (21.5 %). Most studies performed serial SM evaluations (76.1 %). The rectus femoris muscle thickness was evaluated in most studies (67.9 %), followed by the rectus femoris cross-sectional area (54.3 %) and the vastus intermedius muscle thickness (40.2 %). The studies demonstrated the feasibility and reproducibility of US for SM evaluation, especially related to quantitative parameters. Most studies (70.3 %) reported significant SM quantity depletion during hospitalization. However, the accuracy of the US in measuring SM varied across the studies. CONCLUSIONS: The lack of detailed description and standardization in the protocols adopted by the studies included in this scoping review precludes the translation of the evidence related to US for SM assessment into clinical practice.


Asunto(s)
Enfermedad Crítica , Unidades de Cuidados Intensivos , Humanos , Estudios Prospectivos , Reproducibilidad de los Resultados , Músculo Esquelético/diagnóstico por imagen , Ultrasonografía
10.
ACS Appl Mater Interfaces ; 15(40): 46790-46802, 2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37774150

RESUMEN

Aminopolymer-based sorbents are preferred materials for extraction of CO2 from ambient air [direct air capture (DAC) of CO2] owing to their high CO2 adsorption capacity and selectivity at ultra-dilute conditions. While those adsorptive properties are important, the stability of a sorbent is a key element in developing high-performing, cost-effective, and long-lasting sorbents that can be deployed at scale. Along with process upsets, environmental components such as CO2, O2, and H2O may contribute to long-term sorbent instability. As such, unraveling the complex effects of such atmospheric components on the sorbent lifetime as they appear in the environment is a critical step to understanding sorbent deactivation mechanisms and designing more effective sorbents and processes. Here, a poly(ethylenimine) (PEI)/Al2O3 sorbent is assessed over continuous and cyclic dry and humid conditions to determine the effect of the copresence of CO2 and O2 on stability at an intermediate temperature of 70 °C. Thermogravimetric and elemental analyses in combination with in situ horizontal attenuated total reflection infrared (HATR-IR) spectroscopy are performed to measure the extent of deactivation, elemental content, and molecular level changes in the sorbent due to deactivation. The thermal/thermogravimetric analysis results reveal that incorporating CO2 with O2 accelerates sorbent deactivation using these sorbents in dry and humid conditions compared to that using CO2-free air in similar conditions. The in situ HATR-IR spectroscopy results of PEI/Al2O3 sorbent deactivation under a CO2-air environment show the formation of primary amine species in higher quantity (compared to that in conditions without O2 or CO2), which arises due to the C-N bond cleavage at secondary amines due to oxidative degradation. We hypothesize that the formation of bound CO2 species such as carbamic acids catalyzes C-N cleavage reactions in the oxidative degradation pathway by shuttling protons, resulting in a low activation energy barrier for degradation, as probed by metadynamics simulations. In the cyclic experiment after 30 cycles, results show a gradual loss in stability (dry: 29%, humid: 52%) under CO2-containing air (0.04% CO2/21% O2 balance N2). However, the loss in capacity during cyclic studies is significantly less than that during continuous deactivation, as expected.

11.
Nutrients ; 15(9)2023 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-37432223

RESUMEN

(1) Background: Adolescence is characterized by changes in eating habits, with increased consumption of ultra-processed foods and reduced intake of unprocessed or minimally processed foods, which can affect body image satisfaction. Thus, this study aims to verify the association of food consumption according to the degree of processing with body image (dis)satisfaction in adolescents from the 1997/1998 birth cohort of São Luís, Maranhão. (2) Methods: A cross-sectional study was conducted with 2515 adolescents aged between 18 and 19. Food consumption was stratified based on the NOVA classification in culinary preparations, processed foods, and ultra-processed foods, categorized into tertiles. Body image (dis)satisfaction was evaluated based on the Stunkard Body Scale and was classified as satisfaction, dissatisfaction with thinness, and dissatisfaction with excess weight. Multinomial logistic regression was used for associations. (3) Results: Among the adolescents, 77% considered themselves dissatisfied with their body image, with 42.8% dissatisfied with being thin and 34.2% dissatisfied with excess weight. However, food consumption, according to the degree of processing, was not associated with body image (dis)satisfaction. (4) Conclusion: This work highlighted the prevalence of body image dissatisfaction among adolescents but found no association between body (dis)satisfaction and food consumption according to the degree of processing.


Asunto(s)
Insatisfacción Corporal , Imagen Corporal , Adolescente , Humanos , Adulto Joven , Adulto , Estudios Transversales , Cohorte de Nacimiento , Aumento de Peso , Satisfacción Personal
12.
Nutrients ; 14(23)2022 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-36501210

RESUMEN

(1) Background: During adolescence, there are significant changes in food consumption, such as reducing the consumption of in natura or minimally processed foods and increasing the consumption of ultra-processed foods. Thus, eating habits can influence sleep duration and, consequently, affect the quality of life of young people. This study thus aims to estimate the association of consumption of in natura or minimally processed, processed, and ultra-processed foods with sleep durations in adolescents. (2) Methods: This is a cross-sectional study including 964 adolescents (18 to 19 years old) from the 1997 to 1998 birth cohort in São Luís, Maranhão. Food consumption was assessed using the food frequency questionnaire (FFQ) and stratified based on the NOVA classification. Sleep duration was verified using accelerometry in hours. The analysis of the association between the consumption of in natura or minimally processed, processedand ultra-processed foods with sleep durations in adolescents used crude and adjusted linear regression (by gender, age, skin color, education, economic class, work, consumption of alcohol, smoking, screen time, physical activity, use of illicit drugs, anxiety, depressive symptoms, and lean and fat mass). A directed acyclic graph (DAG) was used to determine the minimum set of adjustment factors. (3) Results: Of the 964 individuals evaluated, 52.0% were female. The mean sleep duration was 6 h (± 0.95). In the crude and adjusted analyses, no association was observed between food consumption according to the degree of processing and adolescent sleep durations. (4) Conclusion: There was no association between the consumption of in natura or minimally processed, processed, and ultra-processed foods with sleep durations.


Asunto(s)
Comida Rápida , Duración del Sueño , Adolescente , Humanos , Femenino , Adulto Joven , Adulto , Masculino , Estudios Transversales , Calidad de Vida , Brasil , Ingestión de Alimentos , Manipulación de Alimentos , Ingestión de Energía , Dieta
13.
Animals (Basel) ; 11(12)2021 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-34944213

RESUMEN

The objectives of this study were: (1) to evaluate feed efficiency indexes and their relationships with body measurements and blood and ruminal metabolites in the pre-weaning period; (2) to determine if such measurements can be used as feed-efficiency markers during the pre-weaning period. Holstein-Gyr heifer calves (n = 36), enrolled between 4 and 12 weeks of age, were classified into two residual feed intake (RFI) and residual body weight gain (RG) groups: high efficiency (HE; RFI, n = 10; and RG, n = 9), and low efficiency (LE; RFI, n = 10; and RG, n = 8). Calves were fed whole milk (6 L/day) and solid feed ad libitum. Body developments were measured weekly and feed intake (milk and solid feed) daily during the whole period. Blood samples were collected at 12 weeks of age and analyzed for glucose, insulin and ß-hydroxybutyrate (BHB). Samples of ruminal content were collected on the same day and analyzed for pH, NH3-N, and volatile fatty acids (VFA). Among the growth characteristics, only the initial hip width differed between the RFI groups, and withers height differed between the RG groups. Concentration of BHB was greater and glucose: insulin ratios tended to be greater in LE-RG animals. Butyric acid proportions were similar among RFI groups, but tended to be greater for HE-RG than for LE-RG. Overall, correlation coefficients between RFI or RG and blood, rumen, or morphometric markers were low. Thus, it is unlikely that measurements of metabolic indicators, per se, will be useful in the early identification of more efficient animals. Understanding the underlying physiological basis for improved feed efficiency in dairy heifers requires further investigation.

14.
Heliyon ; 6(7): e04446, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32695917

RESUMEN

The Artisan Minas Cheese (AMC) is the oldest and most traditional Brazilian cheese, it is produced in several regions of the state of Minas Gerais, such as the Serro region. The most striking features of the AMC-Serro are the use of raw milk and natural bacteria from the whey, popularly known as pingo, as well as the use of the rind washing process. The aim of the present study was to evaluate the proteolysis of the AMC-Serro from three different producers, during 60 days of maturation, and to relate the proteolysis to the producing farms, the production season and the rind washing during ripening. For this purpose, TRICINE-SDS-PAGE, proteolysis extension and depth indices, moisture, and texture (firmness) were evaluated. It was concluded that the temperature and moisture of the cheeses, that were determined by the location of the ripening room, the production season and the rind washing, were the most important factors. The degree of proteolysis also had an impact on the water loss during ripening, with effect on cheese safety. The results obtained in this study may be used to better understand the transformations during ripening of AMC-Serro and help the small traditional farmers to improve their product's quality and stability.

15.
Int J Mol Med ; 23(3): 429-35, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19212663

RESUMEN

The aim of this study was to investigate the CCR5 gene and p53 codon 72 polymorphisms in a Brazilian population with breast cancer compared with healthy control subjects and to associate the clinical stage with these genotypes. No differences were detected for the D32 allele between breast cancer patients and the normal healthy donors (p=0.270), although this allele was more often present in blood donors. For p53 genotype analysis, breast cancer patients presented a significant (p<0.05) over-representation of p53 Arg homozygosity (55.5%) compared with the healthy control group (33.3%). Although no statistical difference occurred, a very strong tendency in breast cancer patients in stage III (p=0.0503) presenting homozygous genotype for Arg was verified. Five breast cancer patients were D32 deletion carriers and two patients presenting metastasis showed homozygous genotype for Arg. It is possible that p53 Arg homozygosity is associated with breast cancer and may represent a potential risk factor for breast tumorigenesis. In the present study, a higher percentage of breast cancer patients presented homozygous genotype for Arg and wild-type for CCR5 than the control subjects.


Asunto(s)
Alelos , Neoplasias de la Mama/genética , Polimorfismo Genético , Receptores CCR5/genética , Proteína p53 Supresora de Tumor/genética , Adulto , Anciano , Anciano de 80 o más Años , Brasil , Codón , Femenino , Genotipo , Humanos , Persona de Mediana Edad , Estadificación de Neoplasias , Factores de Riesgo
16.
Folia Biol (Krakow) ; 57(3-4): 165-9, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19777960

RESUMEN

In the present study 25 specimens of Rhamdia quelen from four different localities were analyzed cytogenetically. All showed a diploid number of 58 chromosomes, with a karyotypic formula of 36m + 16sm + 6st and FN = 116. Metacentric B chromosomes showing inter- and intraindividual variation were observed in all populations. C-banding revealed differences in the heterochromatin distribution pattern, with evidence of completely heterochromatic B chromosomes in three populations: Agua das Pedras, Agua dos Patos and Taquari rivers, and partially heterochromatic B chromosomes in the population at the fish farm station in Timbó/SC. The occurrence of B chromosomes in such distinct populations suggests that they could have arisen from the same ancestral state, before the geographic dispersal of this species.


Asunto(s)
Bagres/genética , Cromosomas/genética , Animales , Brasil , Femenino , Cariotipificación , Masculino
17.
Annu Rev Chem Biomol Eng ; 10: 85-104, 2019 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-31173521

RESUMEN

Dwindling fossil fuel resources and substantial release of CO2 from their processing have increased the appeal to use biomass as a sustainable platform for synthesis of chemicals and fuels. Steps toward this will require selective upgrading of biomass to suitable intermediates. Traditionally, biomass upgrading has involved thermochemical processes that require excessive amounts of petrochemical-derived H2 and suffer from poor product selectivity. Electrochemical routes have emerged as promising alternatives because of (a) the replacement of petrochemical-derived H2 by protons generated in situ, (b) mild operating temperatures and pressures, and (c) the use of electrode potential to tune reaction rates and product selectivity. In this review, we highlight the advances in the electrocatalytic hydrogenation and oxidation of biomass-derived platform molecules. The effects of important reaction parameters on electrochemical efficiency and catalytic activity/selectivity are thoroughly discussed. We conclude by summarizing current challenges and discussing future research directions.


Asunto(s)
Biomasa , Técnicas Electroquímicas/métodos , Oxígeno/química , Catálisis , Hidrogenación , Oxidación-Reducción , Protones
19.
New Microbiol ; 31(2): 195-201, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18623984

RESUMEN

This work analyzes the prevalence of TTV DNA in peripheral blood cells from patients with hepatic alterations and healthy blood donors and measures levels of sodium, potassium, urea, creatinine, phosphatase alkaline, total and direct bilirubin, gamma glutamyl transferase (GGT), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in certain randomly selected patients. DNA samples from 111 individuals were evaluated. They were divided into two groups, "A" (study) and "B" (control), including 54 patients with liver enzyme alterations (ALT/AST) presenting non-B-non-C hepatitis and 57 blood donors, respectively. TTV DNA was determined by nested PCR. Certain products of the second-round PCR were sequenced. Serum biochemical assay was performed and disclosed TTV in 31.48% (17/54) of patients in group A and 5.26% (3/57) in the control group B. TTV prevalence was significantly higher in patients with liver disease than in healthy donors. In group A, sodium, potassium, urea, creatinine, phosphatase alkaline, total and direct bilirubin, gamma glutamyl transferase (GGT), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were analyzed in certain randomly selected patients and no significant difference in biochemical levels (p>0.05) was found when TTV infected and noninfected individuals were compared. Knowledge related to TTV has rapidly increased, but many fundamental aspects remain unclear. This led us to question the role of TTV and doubt remains as to whether or not it is just a commensal virus. Further studies are necessary to confirm and extend these findings.


Asunto(s)
Alanina Transaminasa/sangre , Aspartato Aminotransferasas/sangre , Células Sanguíneas/virología , Infecciones por Virus ADN/virología , Torque teno virus/aislamiento & purificación , Análisis Químico de la Sangre , Infecciones por Virus ADN/epidemiología , Hepatitis Viral Humana/virología , Humanos , Reacción en Cadena de la Polimerasa/métodos , Prevalencia
20.
Heart Rhythm ; 14(3): 448-454, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27777148

RESUMEN

BACKGROUND: The capacity of catecholamines to induce ventricular tachycardia (VT) is well documented. OBJECTIVE: The effectiveness of the novel cardiac late sodium inhibitor eleclazine in suppressing catecholamine-induced VT in a large animal model was compared with that of flecainide. METHODS: In 13 closed-chest anesthetized Yorkshire pigs, spontaneous VT and surges in T-wave alternans (TWA) level measured using the Modified Moving Average method were induced by epinephrine (2.0 µg/kg, i.v., bolus over 1 minute). Effects of eleclazine (0.3 mg/kg, i.v., infused over 15 minutes; n = 6) or flecainide (1 mg/kg, i.v., bolus over 2 minutes followed by 1 mg/kg/hr, i.v., for 1 hour; n = 7) on VT incidence and TWA level were measured from right intraventricular electrogram recordings. RESULTS: Epinephrine reproducibly elicited hemodynamically significant spontaneous VT in all 13 pigs and increased TWA level by 33-fold compared to baseline (P < .001). Eleclazine reduced the incidence of epinephrine-induced ventricular premature beats and couplets by 51% (from 31.3 ± 1.91 to 15.2 ± 5.08 episodes; P = .038) and the incidence of 3- to 7-beat VT by 56% (from 10.8 ± 3.45 to 4.7 ± 3.12 episodes; P = .004). Concurrently, the drug reduced the peak epinephrine-induced TWA level by 64% (from 217 ± 22.2 to 78 ± 15.3 µV; P < .001). Flecainide also reduced the incidence of epinephrine-induced ventricular premature beats and couplets by 53% (from 40.4 ± 6.37 to 19.0 ± 2.73 episodes; P = .024) but did not affect the incidence of VT (from 15.0 ± 3.08 to 11.6 ± 2.93 episodes; P = .29) or the peak TWA level (from 207 ± 30.6 to 172 ± 26.2 µV; P = .34). CONCLUSION: Selective inhibition of cardiac late sodium current with eleclazine is more effective than flecainide in reducing catecholamine-induced VT and TWA in an intact porcine model.


Asunto(s)
Catecolaminas/metabolismo , Flecainida/farmacología , Oxazepinas/farmacología , Taquicardia Ventricular , Administración Intravenosa , Animales , Modelos Animales de Enfermedad , Monitoreo de Drogas/métodos , Electrocardiografía/métodos , Hemodinámica/efectos de los fármacos , Porcinos , Taquicardia Ventricular/tratamiento farmacológico , Taquicardia Ventricular/metabolismo , Taquicardia Ventricular/fisiopatología , Resultado del Tratamiento , Bloqueadores del Canal de Sodio Activado por Voltaje/farmacología
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