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2.
Sci Rep ; 12(1): 20113, 2022 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-36418495

RESUMEN

The Standard Cosmological Model has experienced tremendous success at reproducing observational data by assuming a universe dominated by a cosmological constant and dark matter in a flat geometry. However, several studies, based on local measurements, indicate that the universe is expanding too fast, in disagreement with the Cosmic Microwave Background. Taking into account combined data from CMB, Baryon Acoustic Oscillation, and type Ia Supernovae, we show that if the mechanism behind the production of dark matter particles has at least a small non-thermal origin, one can induce larger values of the Hubble rate [Formula: see text], within the [Formula: see text]CDM, to alleviate the trouble with [Formula: see text]. In the presence of non-standard cosmology, however, we can fully reconcile CMB and local measurements and reach [Formula: see text]-74 [Formula: see text].

3.
Domest Anim Endocrinol ; 69: 42-50, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31280025

RESUMEN

Peripheral serotonin has been shown to regulate important physiological functions such as energy homeostasis and immunity, particularly in rodent and humans, but its role is poorly understood in livestock species. Herein, we tested the safety and effectiveness of increasing serotonin bioavailability in preweaned dairy calves by oral supplementation of a serotonin precursor (5-hydroxytryptophan, 5-HTP) or a serotonin reuptake inhibitor (fluoxetine, FLX). Bull Holstein calves (21 ± 2 d old; N = 24) were fed milk replacer (8 L/d) supplemented with either saline as control (CON, 8 mL/d, n = 8), FLX (40 mg/d, approx. 0.8 mg/kg; n = 8), or 5-HTP (90 mg/d, approx. 1.8 mg/kg; n = 8) for 10 consecutive days in a complete randomized block design. Heart rate (HR), respiration rate, rectal temperature, and health scores were recorded daily. Hip height and body weight were measured at d 1, 5, and 10 relative to initiation of supplementation. Blood samples were collected once before the supplementation period (d 1), during the 10-d supplementation period (daily), and during a 14-d withdrawal period (d 2, 3, 4, 7, and 14 relative to initiation of withdrawal). Cerebrospinal fluid and muscle tissue were collected from a subset of calves (n = 12) that were euthanized after the 10-d supplementation or 14-d withdrawal period. Whole blood serotonin concentrations increased in 5-HTP calves and decreased in FLX calves compared with CON (P < 0.001), indicating that serotonin bioavailability was increased in both groups. Whole blood serotonin concentrations of 5-HTP and FLX calves returned to CON levels after 7 d of withdrawal. All calves grew and were considered healthy throughout the study. In fact, calves fed 5-HTP had higher average daily gain compared with CON (0.87 vs 0.66 ± 0.12 kg/d, P = 0.05). Calves fed FLX had lower HR (P = 0.02) and greater red blood cells and hemoglobin counts on d 10 of supplementation compared with CON (P < 0.01). After the 14-d withdrawal period, FLX was not detected in circulation of FLX calves, but was still present in the muscle tissue. Our results demonstrate that manipulation of the serotonin pathway by supplementing FLX or 5-HTP is a feasible and safe approach in preweaned dairy calves; however, it takes more than 14 d for FLX to be completely withdrawn from the body.


Asunto(s)
Conducta Animal/fisiología , Bovinos/crecimiento & desarrollo , Fluoxetina/farmacología , Inhibidores Selectivos de la Recaptación de Serotonina/farmacología , Serotonina/farmacología , Animales , Bovinos/sangre , Bovinos/fisiología , Suplementos Dietéticos , Heces/química , Fluoxetina/sangre , Fluoxetina/líquido cefalorraquídeo , Fluoxetina/farmacocinética , Serotonina/sangre , Serotonina/farmacocinética , Distribución Tisular
4.
J Anal Methods Chem ; 2018: 4869487, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29600112

RESUMEN

A reversed-phase liquid chromatographic separation with pulsed amperometric detection of phenolic acids at a glassy carbon electrode is described. Chromatographic separation was carried out in isocratic conditions using 0.20 mol·L-1 acetic acid (pH 5.0)/water (80 : 20, v/v) as mobile phase under constant working potential mode of 0.80 V. Chromatographic peaks presented high resolution and separation. Calibration curves exhibited excellent correlation coefficients, above 0.995. Linear ranges of the analytes, in mg L-1, were of 0.018-18 (gallic acid), 0.146-19 (vanillic acid), 0.13-17 (caffeic acid), 0.016-16 (ferulic acid), and 0.008-17 (p-coumaric acid), respectively. Limits of detection ranged from 1.6 to 97 µg·L-1 and precision varied in 1.73-3.78% interval. Concentrations of 19 ± 0.51 mg·L-1 and 7.8 ± 2.5 mg·L-1 were found for vanillic and caffeic acids, respectively, in a sugarcane vinasse sample. Gallic, ferulic, and p-coumaric acids were not detected. Recovery results demonstrated that the proposed method is accurate, and it can be used to detect and quantify phenolic acids in sugarcane vinasse without any influence of interferents.

5.
J Fish Biol ; 89(1): 821-46, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27401484

RESUMEN

This study focused on the influence of local-scale environmental factors on key metrics of fish community structure and function at Guanabara Bay, an estuarine system that differs from all other south-western Atlantic estuaries due to the influence of an annual low-intensity upwelling event during late spring and summer, between November and March, when a warm rainy climate prevails. The spatial patterns of the bottom temperature and salinity were more heterogeneous during the rainy season than the dry season, being linked to total precipitation and seasonal oceanographic events. The study identified 130 species and 45 families, placing Guanabara Bay as one of the most species-rich tropical estuarine ecosystems, far exceeding 22 other Brazilian estuaries. These results, in addition to characteristics such as a relatively well-preserved mangrove forest, high productivity and favourable conditions for the growth and reproduction of estuarine species, indicate that Guanabara Bay plays a central role in supporting large populations of fishes, including commercially important species.


Asunto(s)
Ecosistema , Estuarios , Peces , Animales , Bahías , Brasil , Lluvia , Salinidad , Estaciones del Año , Temperatura , Clima Tropical
6.
Braz J Med Biol Res ; 49(5): e5244, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27119429

RESUMEN

Levamisole has been increasingly used as an adulterant of cocaine in recent years, emerging as a public health challenge worldwide. Levamisole-associated toxicity manifests clinically as a systemic vasculitis, consisting of cutaneous, hematological, and renal lesions, among others. Purpura retiform, cutaneous necrosis, intravascular thrombosis, neutropenia, and less commonly crescentic nephritis have been described in association with anti-neutrophil cytoplasmic antibodies (ANCAs) and other autoantibodies. Here we report the case of a 49-year-old male who was a chronic cocaine user, and who presented spontaneous weight loss, arthralgia, and 3 weeks before admission purpuric skin lesions in the earlobes and in the anterior thighs. His laboratory tests on admission showed serum creatinine of 4.56 mg/dL, white blood count 3,800/µL, hemoglobin 7.3 g/dL, urinalysis with 51 white blood cells/µL and 960 red blood cells/µL, and urine protein-to-creatinine ratio 1.20. Serum ANCA testing was positive (>1:320), as well as serum anti-myeloperoxidase and anti-proteinase 3 antibodies. Urine toxicology screen was positive for cocaine and levamisole, with 62.8% of cocaine, 32.2% of levamisole, and 5% of an unidentified substance. Skin and renal biopsies were diagnostic for leukocytoclastic vasculitis and pauci-immune crescentic glomerulonephritis, respectively. The patient showed a good clinical response to cocaine abstinence, and use of corticosteroids and intravenous cyclophosphamide. Last serum creatinine was 1.97 mg/dL, white blood cell count 7,420/µL, and hemoglobin level 10.8 g/dL. In levamisole-induced systemic vasculitis, the early institution of cocaine abstinence, concomitant with the use of immunosuppressive drugs in severe cases, may prevent permanent end organ damage and associate with better clinical outcomes.


Asunto(s)
Cocaína/efectos adversos , Glomerulonefritis/inducido químicamente , Levamisol/efectos adversos , Púrpura/inducido químicamente , Vasculitis Sistémica/inducido químicamente , Glomerulonefritis/patología , Humanos , Masculino , Persona de Mediana Edad , Púrpura/patología , Vasculitis Sistémica/patología
7.
Braz J Med Biol Res ; 49(4): e5176, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27007656

RESUMEN

HIV infection has a broad spectrum of renal manifestations. This study examined the clinical and histological manifestations of HIV-associated renal disease, and predictors of renal outcomes. Sixty-one (64% male, mean age 45 years) HIV patients were retrospectively evaluated. Clinical presentation and renal histopathology were assessed, as well as CD4 T-cell count and viral load. The predictive value of histological lesion, baseline CD4 cell count and viral load for end-stage renal disease (ESRD) or death were determined using the Cox regression model. The outcomes of chronic kidney disease (CKD) and ESRD or death were evaluated by baseline CD4 cell count. The percent distribution at initial clinical presentation was non-nephrotic proteinuria (54%), acute kidney injury (28%), nephrotic syndrome (23%), and chronic kidney disease (22%). Focal segmental glomerulosclerosis (28%), mainly the collapsing form (HIVAN), acute interstitial nephritis (AIN) (26%), and immune complex-mediated glomerulonephritis (ICGN) (25%) were the predominant renal histology. Baseline CD4 cell count ≥ 200 cells/mm3 was a protective factor against CKD (hazard ratio=0.997; 95%CI=0.994-0.999; P=0.012). At last follow-up, 64% of patients with baseline CD4 ≥ 200 cells/mm3 had eGFR >60 mL·min-1·(1.73 m2)-1 compared to the other 35% of patients who presented with CD4 <200 cells/mm3 (log rank=9.043, P=0.003). In conclusion, the main histological lesion of HIV-associated renal disease was HIVAN, followed by AIN and ICGN. These findings reinforce the need to biopsy HIV patients with kidney impairment and/or proteinuria. Baseline CD4 cell count ≥ 200 cells/mm3 was associated with better renal function after 2 years of follow-up.


Asunto(s)
Infecciones por VIH/complicaciones , Insuficiencia Renal Crónica/virología , Nefropatía Asociada a SIDA/patología , Biopsia , Recuento de Linfocito CD4 , Progresión de la Enfermedad , Femenino , Tasa de Filtración Glomerular , Glomerulonefritis/patología , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Modelos de Riesgos Proporcionales , Proteinuria/sangre , Insuficiencia Renal Crónica/patología , Estudios Retrospectivos , Albúmina Sérica , Estadísticas no Paramétricas , Factores de Tiempo , Carga Viral
8.
Int J Sports Med ; 37(6): 464-9, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26990721

RESUMEN

This study compared variation in size, function and sport-specific technical skills of youth soccer players associated with differences in biological maturity status. 60 male soccer players of under-14 (U14) and under-17 (U17) categories were submitted to anthropometric and body composition measurements as well as motor and soccer-specific technical skill tests. Skeletal maturity was determined by skeletal age. Athletes of both categories were classified as early, on-time or late-maturing, according to the difference between chronological age and skeletal age. Body mass and height were lower in the late athletes, independent of category (P<0.01). Differences in adiposity were found only between athletes of the U14 (late

Asunto(s)
Determinación de la Edad por el Esqueleto , Rendimiento Atlético/fisiología , Fútbol , Adiposidad , Adolescente , Desarrollo del Adolescente , Factores de Edad , Antropometría , Atletas , Estatura , Tamaño Corporal , Capacidad Cardiovascular , Niño , Humanos , Masculino , Destreza Motora , Fuerza Muscular
9.
Braz. j. med. biol. res ; 49(4): e5176, 2016. tab, graf
Artículo en Inglés | LILACS | ID: biblio-951666

RESUMEN

HIV infection has a broad spectrum of renal manifestations. This study examined the clinical and histological manifestations of HIV-associated renal disease, and predictors of renal outcomes. Sixty-one (64% male, mean age 45 years) HIV patients were retrospectively evaluated. Clinical presentation and renal histopathology were assessed, as well as CD4 T-cell count and viral load. The predictive value of histological lesion, baseline CD4 cell count and viral load for end-stage renal disease (ESRD) or death were determined using the Cox regression model. The outcomes of chronic kidney disease (CKD) and ESRD or death were evaluated by baseline CD4 cell count. The percent distribution at initial clinical presentation was non-nephrotic proteinuria (54%), acute kidney injury (28%), nephrotic syndrome (23%), and chronic kidney disease (22%). Focal segmental glomerulosclerosis (28%), mainly the collapsing form (HIVAN), acute interstitial nephritis (AIN) (26%), and immune complex-mediated glomerulonephritis (ICGN) (25%) were the predominant renal histology. Baseline CD4 cell count ≥200 cells/mm3 was a protective factor against CKD (hazard ratio=0.997; 95%CI=0.994-0.999; P=0.012). At last follow-up, 64% of patients with baseline CD4 ≥200 cells/mm3 had eGFR >60 mL·min-1·(1.73 m2)-1 compared to the other 35% of patients who presented with CD4 <200 cells/mm3 (log rank=9.043, P=0.003). In conclusion, the main histological lesion of HIV-associated renal disease was HIVAN, followed by AIN and ICGN. These findings reinforce the need to biopsy HIV patients with kidney impairment and/or proteinuria. Baseline CD4 cell count ≥200 cells/mm3 was associated with better renal function after 2 years of follow-up.


Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Infecciones por VIH/complicaciones , Insuficiencia Renal Crónica/virología , Proteinuria/sangre , Factores de Tiempo , Biopsia , Albúmina Sérica , Modelos de Riesgos Proporcionales , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Nefropatía Asociada a SIDA/patología , Estadísticas no Paramétricas , Progresión de la Enfermedad , Recuento de Linfocito CD4 , Carga Viral , Insuficiencia Renal Crónica/patología , Tasa de Filtración Glomerular , Glomerulonefritis/patología
10.
Carbohydr Res ; 344(18): 2591-5, 2009 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-19853840

RESUMEN

Chitosan is a polysaccharide used in a broad range of applications. Many of its unique properties come from the presence of amino groups in its structure. A proper quantification of these amino groups is very important, in order to specify if a given chitosan sample can be used in a particular application. In this work, a comparison between the determination of chitosan degree of deacetylation by conductometry and CHN elemental analysis was carried out, using a rigorous error analysis. Accurate expressions relating CHN composition, conductometric titration, and degree of deacetylation, in conjunction with their associated errors, were developed and reported in this note. Error analysis showed conductometric analysis as an inexpensive and secure method for the determination of the degree of deacetylation of chitosan.


Asunto(s)
Quitosano/química , Acetilación , Aminas/análisis , Conductometría
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