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1.
Nature ; 616(7957): 448-451, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36858072

RESUMEN

The Double Asteroid Redirection Test (DART) spacecraft successfully performed the first test of a kinetic impactor for asteroid deflection by impacting Dimorphos, the secondary of near-Earth binary asteroid (65803) Didymos, and changing the orbital period of Dimorphos. A change in orbital period of approximately 7 min was expected if the incident momentum from the DART spacecraft was directly transferred to the asteroid target in a perfectly inelastic collision1, but studies of the probable impact conditions and asteroid properties indicated that a considerable momentum enhancement (ß) was possible2,3. In the years before impact, we used lightcurve observations to accurately determine the pre-impact orbit parameters of Dimorphos with respect to Didymos4-6. Here we report the change in the orbital period of Dimorphos as a result of the DART kinetic impact to be -33.0 ± 1.0 (3σ) min. Using new Earth-based lightcurve and radar observations, two independent approaches determined identical values for the change in the orbital period. This large orbit period change suggests that ejecta contributed a substantial amount of momentum to the asteroid beyond what the DART spacecraft carried.

2.
J Strength Cond Res ; 38(5): 951-956, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38662887

RESUMEN

ABSTRACT: González-Cano, H, Martín-Olmedo, JJ, Baz-Valle, E, Contreras, C, Schoenfeld, BJ, García-Ramos, A, Jiménez-Martínez, P, and Alix-Fages, C. Do muscle mass and body fat differ between elite and amateur natural physique athletes on competition day? A preliminary, cross-sectional, anthropometric study. J Strength Cond Res 38(5): 951-956, 2024-Natural physique athletes strive to achieve low body fat levels while promoting muscle mass hypertrophy for competition day. This study aimed to compare the anthropometric characteristics of natural amateur (AMA) and professional (PRO) World Natural Bodybuilding Federation (WNBF) competitors. Eleven male natural physique athletes (6 PRO and 5 AMA; age = 24.8 ± 2.3 years) underwent a comprehensive anthropometric evaluation following the International Society for the Advancement of Kinanthropometry protocol within a 24-hour time frame surrounding the competition. The 5-component fractionation method was used to obtain the body composition profile of the muscle, adipose, bone, skin, and residual tissues. Five physique athletes exceeded the 5.2 cutoff point of muscle-to-bone ratio (MBR) for natural athletes. Professional physique athletes were older than AMA physique athletes (p = 0.05), and they also presented larger thigh girths (p = 0.005) and bone mass (p = 0.019) compared with AMA physique athletes. Although no statistically significant between-group differences were observed in body mass, height, or body fat levels, PRO physique athletes exhibited a higher body mass index (BMI; AMA: 24.45 ± 0.12; PRO: 25.52 ± 1.01; p = 0.048), lean body mass (LBM; AMA: 64.49 ± 2.35; PRO: 69.80 ± 3.78; p = 0.024), fat-free mass (FFM; AMA: 71.23 ± 3.21; PRO: 76.52 ± 4.31; p = 0.05), LBM index (LBMI; AMA: 20.65 ± 0.52; PRO: 21.74 ± 0.85; p = 0.034), and fat-free mass index index (FFMI; AMA: 22.80 ± 0.22; PRO: 23.83 ± 0.90; p = 0.037) compared with AMA physique athletes. These findings highlight the unique characteristics and anthropometric differences between PRO and AMA natural physique athletes on competition day, emphasizing the significance of age, thigh girth, bone mass, BMI, LBM, FFM, and FFMI in distinguishing these 2 groups. Based on our findings, the established boundaries for muscle mass in natural physique athletes, based on FFMI and MBR, warrant reconsideration.


Asunto(s)
Tejido Adiposo , Antropometría , Atletas , Composición Corporal , Músculo Esquelético , Humanos , Masculino , Estudios Transversales , Adulto Joven , Tejido Adiposo/anatomía & histología , Tejido Adiposo/fisiología , Músculo Esquelético/fisiología , Músculo Esquelético/anatomía & histología , Adulto , Composición Corporal/fisiología , Levantamiento de Peso/fisiología
3.
Neuropsychobiology ; 82(1): 33-39, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36577389

RESUMEN

INTRODUCTION: Research in humans has identified a link between hypoglycemia and anxiety. The present study examined anxiety-like behaviors in rats that were subjected to hypoglycemia that was produced by an acute injection of insulin. Healthy female Wistar rats were subjected to a battery of tests to explore anxiety (elevated plus maze) and locomotion (open field test). METHODS: The control (CT) group received 0.9% saline (3 mL/kg, p.o.). Three other groups received 50% glucose (3 mL/kg, p.o.), insulin (0.1 UI, s.c.), or insulin + glucose (normalized glycemia [NG] group). RESULTS: Normal glycemic values were found in the CT and NG groups. Therefore, a single control (CT-NG) group was formed for statistical comparisons. The highest glycemic value was found in the glucose-induced hyperglycemia group. The lowest glycemic value was found in the insulin-induced hypoglycemia group. In the open field test, the most significant change was a higher number of rearings in the hypoglycemia group. In the elevated plus maze test, the CT-NG group and hyperglycemia groups exhibited similar behavior, whereas the hypoglycemia group spent a shorter time on the open arms and a longer time on the closed arms and had the highest Anxiety Index. Hyperglycemia is a typical characteristic of diabetes. Insulin normalizes glycemia. In the present study, insulin produced anxiety only when it produced hypoglycemia. CONCLUSION: The main effect of acute hypoglycemia is anxiety, which may be considered an early sign of hypoglycemia in an allostatic process.


Asunto(s)
Hiperglucemia , Hipoglucemia , Humanos , Ratas , Femenino , Animales , Ratas Wistar , Ansiedad , Hipoglucemia/complicaciones , Hipoglucemia/inducido químicamente , Insulina , Hiperglucemia/inducido químicamente , Hiperglucemia/complicaciones , Glucosa/efectos adversos
4.
Ecotoxicol Environ Saf ; 245: 114090, 2022 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-36162350

RESUMEN

Air pollution includes polycyclic aromatic hydrocarbons (PAHs), which have been correlated to endocrine disruptor pathways during early pregnancy. PAHs have been found in the placenta and cord blood, which may affect the hormones involved in placental development. We studied the effects of some airborne PAHs on beta human chorionic gonadotropin (ß-hCG) and progesterone production by using a syncytial BeWo cell line as a placental model. PAH congeners were spiked in silicon rubber membrane (SRMs) and were then introduced into the cell medium by the passive dosing method to reach a freely dissolved concentration for BeWo cell exposure. Ultrahigh-performance liquid chromatography coupled with a diode array detector was used to analyze the PAHs, and electrochemiluminescence was used to test the hormone levels. Our results showed that passive dosing can deliver low levels of PAH congeners in the cell medium, which allowed us to calculate the individual release constants at equilibrium and to estimate their effects. Benzo[a]pyrene was released quickly from the SRMs to the cell medium, which can be attributed to its lipophilic properties. The PAHs were shown to decrease the ß-hCG level in the short term and progesterone level in the long term, so they may serve as a pathway for endocrine disorder in trophoblastic cells. This approximation may explain observations of impaired endometrium receptivity and placental dysfunction, which enhance adverse pregnancy outcomes such as embryonic mortality and intrauterine growth restriction.


Asunto(s)
Disruptores Endocrinos , Hidrocarburos Policíclicos Aromáticos , Benzo(a)pireno/análisis , Línea Celular , Gonadotropina Coriónica/análisis , Gonadotropina Coriónica/metabolismo , Gonadotropina Coriónica/farmacología , Disruptores Endocrinos/análisis , Femenino , Humanos , Técnicas In Vitro , Placenta/metabolismo , Hidrocarburos Policíclicos Aromáticos/análisis , Embarazo , Progesterona/metabolismo , Goma , Silicio/farmacología
5.
Clin Transplant ; 35(4): e14227, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33484027

RESUMEN

The absence of afferent nerves for heart rate (HR) regulation leaves the transplanted heart under the influence of its internal and hormonal control. The HR of heart transplantation (HTx) recipients varies from to 90-110 bpm, indicating a lack of vagal parasympathetic tone. We hypothesized that the reduction in mean HR using an If-channel antagonist (ivabradine) could be effective and safe in HTx recipients. The primary objective of this open-label randomized clinical trial was to compare the mean HR at 3, 6, 12, 18, 24, 30, and 36 months after randomization between an ivabradine plus conventional treatment group (IG) and conventional treatment alone group (CG). The secondary objectives were reduction in mortality, graft dysfunction, and ventricular mass. All patients were randomized between 1 and 12 months after HTx. Ivabradine started at randomization. Of the 35 patients, 54.28% were in the CG and 45.72% in the IG. There were no significant between-group differences in demographics. Over time, the HR differences between the groups became significant (P < .01). There were no significant between-group differences in mortality, graft dysfunction, and ventricular mass. We conclude that ivabradine could effectively and consistently reduce the HR in HTx recipients.


Asunto(s)
Benzazepinas , Trasplante de Corazón , Benzazepinas/uso terapéutico , Corazón , Frecuencia Cardíaca , Humanos , Ivabradina/uso terapéutico , Resultado del Tratamiento
6.
Neuropsychobiology ; 80(6): 483-492, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33827082

RESUMEN

BACKGROUND/AIMS: Anti-immobility actions of insulin in diabetic rats that are subjected to the forced swim test (FST) have been reported. In this test, low doses of antidepressants exert actions after long-term treatment, without affecting locomotor activity in healthy rats. Few studies have compared acute and chronic actions of insulin with antidepressants in healthy rats. METHODS: We hypothesized that if insulin exerts a true anti-immobility action, then its effects must be comparable to fluoxetine in both a 1-day treatment regimen and a 21-day treatment regimen in healthy, gonadally intact female Wistar rats. RESULTS: The results showed that low levels of glycemia were produced by all treatments, including fluoxetine, and glycemia was lower in proestrus-estrus than in diestrus-metestrus. None of the treatments or regimens produced actions on indicators of anxiety in the elevated plus maze. Insulin in the 1-day regimen increased the number of crossings and rearings in the open field test and caused a low cumulative immobility time in the FST. These actions disappeared in the 21-day regimen. Compared with the other treatments, fluoxetine treatment alone or combined with insulin produced a longer latency to the first period of immobility and a shorter immobility time in the chronic regimen in the FST, without affecting locomotor activity, and more pronounced actions were observed in proestrus-estrus (i.e., a true anti-immobility effect). CONCLUSION: These results indicate that insulin does not produce a true antidepressant action in healthy rats. The purported antidepressant effects that were observed were instead attributable to an increase in locomotor activity only in the 1-day regimen.


Asunto(s)
Diabetes Mellitus Experimental , Insulina , Animales , Antidepresivos/farmacología , Femenino , Ratas , Ratas Wistar , Natación
7.
Microb Pathog ; 141: 103987, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31962184

RESUMEN

Sporotrichosis is an emergent subcutaneous mycosis that is a threat to both humans and other animals. Sporotrichosis is acquired by the traumatic implantation of species of the Sporothrix genus. Added to the detoxification systems, pathogenic fungi possess different mechanisms that allow them to survive within the phagocytic cells of their human host during the oxidative burst. These mechanisms greatly depend from the cell wall (CW) since phagocytic cells recognize pathogens through specific receptors associated to the structure. To date, there are no studies addressing the modulation of the expression of S. schenckii CW proteins (CWP) in response to reactive oxygen species (ROS). Therefore, in this work, a proteomic analysis of the CW of S. schenckii in response to the oxidative agent menadione (O2•-) was performed. Proteins that modulate their expression were identified which can be related to the fungal survival mechanisms within the phagocyte. Among the up-regulated CWP in response to the oxidative agent, 13 proteins that could be involved in the mechanisms of oxidative stress response in S. schenckii were identified. The proteins identified were thioredoxin1 (Trx1), superoxide dismutase (Sod), GPI-anchored cell wall protein, ß-1,3-endoglucanase EglC, glycoside hydrolase (Gh), chitinase, CFEM domain protein, glycosidase crf1, covalently-linked cell wall protein (Ccw), 30 kDa heat shock protein (Hsp30), lipase, trehalase (Treh), fructose-bisphosphate aldolase (Fba1) and citrate synthase (Cs). The identification of CWP that modulates their expression in response to superoxide ion (O2•-) in S. schenckii is a useful approach to understand how the fungus defends itself against ROS, in order to evade the phagocytic cells from the host and cause the infection.


Asunto(s)
Pared Celular/metabolismo , Estrés Oxidativo/efectos de los fármacos , Sporothrix , Vitamina K 3/farmacología , Animales , Pared Celular/química , Enfermedades Transmisibles Emergentes/inmunología , Enfermedades Transmisibles Emergentes/microbiología , Proteínas Fúngicas/análisis , Proteínas Fúngicas/metabolismo , Regulación Fúngica de la Expresión Génica/efectos de los fármacos , Genoma Fúngico , Evasión Inmune , Oxidantes/farmacología , Estrés Oxidativo/fisiología , Fagocitos/inmunología , Fagocitos/microbiología , Proteómica , Sporothrix/efectos de los fármacos , Sporothrix/genética , Sporothrix/metabolismo , Esporotricosis/inmunología
8.
Clin Transplant ; 33(10): e13693, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31403724

RESUMEN

INTRODUCTION: Primary graft failure (PGF) is an important contributor to early mortality, accounting for 41% of deaths within the first 30 days after heart transplantation (HT). Donor hypernatremia has been associated with PGF development. However, controversial data exist regarding the impact of sodium deregulation in patient survival after HT. This study aimed to assess the influence of donor hypernatremia on PGF development and to determine the serum sodium level threshold to assist in decision-making for organ procurement. METHODS: The medical record from 200 HT patients and organ donors were retrospectively assessed and categorized by PGF occurrence. Donor sodium levels were compared and cut-off points obtained by receiver operating characteristic (ROC) curve. A multiple logistic regression model was applied to assess the effects of factors and covariates that influence PGF development. RESULTS: Sodium levels of donors were significantly higher in recipients who developed PGF than those who did not develop PGF (162 vs. 153 mmol/L, P = .001). The sodium cut-off value determined by the ROC curve was 159 mmol/L. The group who received organs from donors with a serum sodium concentration ≥159 mmol/L had a higher incidence of PGF (63.3% vs 32.4%, P < .001). Furthermore, donor sodium levels ≥159 mmol/L increased the likelihood of recipients developing PGF by 3.4 times. It is also observed that the incidence of donor smoking addiction was significantly higher in the PGF group (28.6% vs. 11.5%, P = .004) and donor smoking addiction increased the risk of developing PGF by 2.8 times. CONCLUSION: Smoking addiction and the application of suboptimal organs from donors with hypernatremia contribute to primary graft failure in heart transplantation.


Asunto(s)
Rechazo de Injerto/etiología , Trasplante de Corazón/efectos adversos , Hipernatremia/fisiopatología , Complicaciones Posoperatorias/etiología , Fumar/fisiopatología , Donantes de Tejidos/provisión & distribución , Adulto , Femenino , Estudios de Seguimiento , Rechazo de Injerto/patología , Supervivencia de Injerto , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/patología , Pronóstico , Estudios Retrospectivos , Factores de Riesgo
9.
Bull Math Biol ; 81(10): 3998-4021, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31392576

RESUMEN

We develop a mathematical model to study the immediate effect of low-dose radiation on the G2 checkpoint and the G2/M transition of the cell cycle via a radiation pathway (the ATM-Chk2 pathway) of an individual mammalian cell. The model consists of a system of nonlinear differential equations describing the dynamics of a network of regulatory proteins that play key roles in the G2/M transition, cell cycle oscillations, and the radiation pathway. We simulate the application of a single pulse of low-dose radiation at different intensities ([Formula: see text] 0-0.4 Gy) and times during the latter part of the G2-phase. We use bifurcation analysis to characterize the effect of radiation on the G2/M transition via the ATM-Chk2 pathway. We show that radiation between 0.1 and 0.3 Gy can delay the G2/M transition, and radiation higher than 0.3 Gy can fully activate the G2 checkpoint. Also, our results show that radiation can be low enough to neither delay the G2/M transition nor activate the G2 checkpoint ([Formula: see text] 0.1 Gy). Our model supports the idea that the cell response to radiation during G2-phase explains hyper-radiosensitivity and increased radioresistance (HRS/IRR) observed at low dose.


Asunto(s)
Puntos de Control de la Fase G2 del Ciclo Celular/efectos de la radiación , Modelos Biológicos , Animales , Proteínas de la Ataxia Telangiectasia Mutada/metabolismo , Proliferación Celular/fisiología , Proliferación Celular/efectos de la radiación , Supervivencia Celular/fisiología , Supervivencia Celular/efectos de la radiación , Quinasa de Punto de Control 2/metabolismo , Relación Dosis-Respuesta en la Radiación , Puntos de Control de la Fase G2 del Ciclo Celular/fisiología , Humanos , Conceptos Matemáticos , Dinámicas no Lineales , Tolerancia a Radiación/fisiología
10.
Pharm Biol ; 53(12): 1741-51, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25853961

RESUMEN

CONTEXT: Asclepias subulata Decne. (Apocynaceae) is a shrub used in the Mexican traditional medicine for the treatment of cancer. OBJECTIVE: The objective of this study was to evaluate the antiproliferative activity of methanol extract of aerial parts of A. subulata and its fractions against different cancer cell lines. Additionally, we analyzed the mechanism of action of the active fractions. MATERIALS AND METHODS: Methanol extract fractions were prepared by serial extraction with n-hexane, ethyl acetate, and ethanol. The antiproliferative activity of methanol extract and its fractions was evaluated, against several murine (M12.C3.F6, RAW 264.7, and L929) and human (HeLa, A549, PC-3, LS 180, and ARPE-19) cell lines by the MTT assay, using concentrations of 0.4-400 µg/mL for 48 h. Ethanol and residual fractions were separated using silica gel column. Apoptosis induction of cancer cells was evaluated by Annexin and JC-1 staining using flow cytometry. RESULTS: Methanol extract and its fractions showed antiproliferative activity against all human cancer cell lines tested. Methanol extract had the highest antiproliferative activity on A549 and HeLa cells (IC50 values < 0.4 and 8.7 µg/mL, respectively). Ethanol and residual fractions exerted significant antiproliferative effect on A549 (IC50 < 0.4 µg/mL) and PC3 cells (IC50 1.4 and 5.1 µg/mL). Apoptotic assays showed that CEF7, CEF9, CRF6, and CRF5 fractions induced mitochondrial depolarization in A549 cells, 70, 73, 77, and 80%, respectively. Those fractions triggered the apoptosis mitochondrial pathway. CONCLUSION: Our data show that A. subulata extracts have potent antiproliferative properties on human cancer cell lines. This plant should be considered an important source of potent anticancer compounds.


Asunto(s)
Apoptosis/efectos de los fármacos , Asclepias , Proliferación Celular/efectos de los fármacos , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Animales , Apoptosis/fisiología , Proliferación Celular/fisiología , Relación Dosis-Respuesta a Droga , Flores , Células HeLa , Humanos , Ratones , Tallos de la Planta
11.
Invest Clin ; 56(2): 123-36, 2015 Jun.
Artículo en Español | MEDLINE | ID: mdl-26299054

RESUMEN

Numerous studies report adverse effects of pesticides on male reproductive health. The objectives of this study were to investigate whether there is a relationship between occupational exposure to pesticides and semen quality, and to determine whether chronic exposure to pesticides differentially affects semen quality in men of different ages. A comparative study of 64 farmers and 64 control men was performed. The farmers were interviewed to determine their occupational history and particularly, activities that may involve exposure to pesticides. Semen parameters were evaluated and a comparative analysis of semen variables between exposed and control groups, as well as between age groups: 18-29, 30-37 and 38-60 years was done. Significant alterations of some semen parameters in the exposed group were found, such as: decreases in sperm concentration, slow progressive motility and sperm membrane integrity; at the same time, increases in eosin Y positive and sperm DNA fragmentation index. The results obtained by age groups showed significant differences between exposed and control groups for the parameters of membrane integrity, eosin Y positive and sperm DNA fragmentation index, being the exposed group between 18-29 years that showed the highest altered cases of these parameters. Our results prove that occupational pesticide exposure is associated with alterations in sperm quality, creating a risk to farm workers in their reproductive capacity.


Asunto(s)
Exposición Profesional/efectos adversos , Plaguicidas/toxicidad , Semen/efectos de los fármacos , Espermatozoides/efectos de los fármacos , Adolescente , Adulto , Factores de Edad , Agricultura , Estudios de Casos y Controles , Humanos , Masculino , Persona de Mediana Edad , Análisis de Semen , Recuento de Espermatozoides , Motilidad Espermática/efectos de los fármacos , Venezuela , Adulto Joven
12.
Eur J Nutr ; 53(2): 567-74, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-23892521

RESUMEN

PURPOSE: Our objective was to compare the absorption of microencapsulated ferric saccharate (MFS) and ferrous sulfate (FS) in a fortified milk product, using a crossover design. METHODS: Seventeen non-iron-deficient healthy adults from both sexes participated in the study. On each intervention day (days 1 and 8), after an overnight fast, the volunteers consumed one type of product (test or control) and blood sampling was carried out at different times. The interventions days were separated by 7-day washout periods. This study was double blinded, crossover and randomized for nature of the test meals. The primary outcomes of the study were total serum iron and transferrin saturation. RESULTS: No significant differences could be observed in serum iron concentration during the 6-h postprandial study due to the type of milk product consumed, and there was neither an effect of time nor an interaction between the type of milk product and time. Transferrin saturation significantly increased after the intake of both products (P < 0.005), reaching a peak value between hours 2 and 4. No significant differences were detected between MFS and FS, indicating that iron absorption from MFS is equivalent to absorption from FS. CONCLUSIONS: MFS is a new ingredient that allows the fortification of a wide range of food products, including heat-processed and non-acidic products with similar absorption to FS, designed to produce neither organoleptic changes nor off-color development during storage of fortified food.


Asunto(s)
Compuestos Férricos/farmacocinética , Compuestos Ferrosos/farmacocinética , Ácido Glucárico/farmacocinética , Boca/metabolismo , Absorción , Adulto , Animales , Índice de Masa Corporal , Estudios Cruzados , Método Doble Ciego , Composición de Medicamentos , Femenino , Compuestos Férricos/administración & dosificación , Sacarato de Óxido Férrico , Ferritinas/sangre , Compuestos Ferrosos/administración & dosificación , Alimentos Fortificados , Ácido Glucárico/administración & dosificación , Humanos , Hierro/sangre , Masculino , Leche , Periodo Posprandial
13.
Exp Parasitol ; 145 Suppl: S57-61, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25076486

RESUMEN

Since the first report of Balamuthia mandrillaris as a causative agent of granulomatous amoebic encephalitis in humans, the environmental niche of this amoeba was assumed to be restricted to soil and dust. A single isolation from water was recently made independently by us from Northern Mexico. Now we report the isolation of 8 new strains of B. mandrillaris from Mexico. This continues the pattern of an excess of isolates from North America, compared to other parts of the world. All of the new isolates are environmental isolates, 7 from water samples and one from soil. The identity of each isolate was confirmed by PCR and by examining the sequences of the mitochondrial 16S-like rRNA gene. Success in amplification was determined using comparisons of amplifications of DNA from the strain CDC: V039 and the water strain (ITSON-BM1) as positive controls. The DNA sequences of the new isolates were compared to older strains from clinical cases using phylogenetic analysis, showing very high sequence similarity. The similarity among the new isolates and with previous clinical and environmental isolates of B. mandrillaris was also examined using biochemical and immunological studies. High homogeneity of total protein products, and similarity in antigenic moiety among the eight new isolates and two controls was found. Taken together, the molecular and biochemical studies indicate very low levels of genetic variation within B. mandrillaris.


Asunto(s)
Balamuthia mandrillaris/genética , Agua Dulce/parasitología , Proteínas Protozoarias/química , Suelo/parasitología , Balamuthia mandrillaris/clasificación , Balamuthia mandrillaris/aislamiento & purificación , Western Blotting , Medios de Cultivo , Electroforesis en Gel de Poliacrilamida , México , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN
14.
Behav Brain Res ; 459: 114795, 2024 02 29.
Artículo en Inglés | MEDLINE | ID: mdl-38048910

RESUMEN

Gonadal hormones may influence sexual activity by reducing anxiety. The basolateral amygdala (BLA) and prelimbic (PL) and infralimbic (IL) cortical regions comprise a loop that is related to fear, anxiety, and social behavior. In female ovariectomized rats, actions of estradiol, progesterone, and sequential estradiol and progesterone administration were explored in the open field test (OFT) and plus maze test (PMT) to evaluate signs of anxiety-like behavior. The three hormonal treatments reduced indicators of anxiety in the PMT but did not influence behavior in the OFT. In the same behaviorally tested rats under urethane anesthesia, single-unit extracellular recordings were obtained from the PL and IL during electrical stimulation of the BLA. The analysis of 250 ms peristimulus histograms showed that BLA stimulation produced two kinds of response. A small group of neurons increased their firing rate after BLA stimulation. Most neurons exhibited a reduction of spiking. Neurons that increased their firing rate after BLA stimulation did not show any difference with the hormonal treatments. In neurons that were inhibited by BLA stimulation, estradiol reduced the neuronal firing rate in the PL and IL, and progesterone alone and the sequential administration of estradiol followed by progesterone administration 24 h later (priming) increased the firing rate during the 240 ms before BLA stimulation. Analyses of responsivity of the PL and IL during electrical stimulation of the BLA indicated that estradiol, progesterone, and estradiol followed by progesterone administration 24 h later (priming) reduced inhibitory actions of the BLA on the PL but not IL. In the BLA-IL connection, progesterone exacerbated the inhibitory response. These findings indicate that anxiolytic actions of estradiol, progesterone, and estradiol followed by progesterone administration 24 h later (priming) correspond to lower BLA-PL responsivity. Actions of progesterone on BLA-IL responsivity appear to contribute to sexual activity by interacting with other forebrain structures that are also related to sexual receptivity.


Asunto(s)
Corteza Prefrontal , Progesterona , Ratas , Femenino , Animales , Progesterona/farmacología , Corteza Prefrontal/fisiología , Amígdala del Cerebelo/fisiología , Ansiedad/tratamiento farmacológico , Estradiol/farmacología
15.
Neurosci Lett ; 834: 137848, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38823510

RESUMEN

Ketamine is a dissociative anesthetic that has been proposed to be a useful alternative in cases of a poor response to other treatments in patients with depression. Remarkably, beneficial clinical actions of ketamine are detected once its psychotropic actions disappear. Therefore, clinical actions may occur independently of dose. Most current studies focus on actions of ketamine on neurotrophic factors, but few studies have investigated actions of ketamine on neural structures for which actions of antidepressants have been previously explored. Lateral septal nucleus (LSN) stimulation reduces neural activity in the prelimbic cortex (PL) and infralimbic cortex (IL) subregions of the medial prefrontal cortex (mPFC). Fluoxetine increases inhibitory responsivity of the LSN-IL connection. In the present study, actions of an anesthetic dose of ketamine were compared with a high dose of fluoxetine on behavior and neural responsivity 24 h after drug administration. Fluoxetine reduced immobility in the forced swim test without changing locomotor activity in the open field test. Ketamine strongly decreased locomotor activity and did not produce changes in immobility. In another set of Wistar rats that received similar drug treatment regimens, the results indicated that LSN stimulation in saline-treated animals produced a long-lasting inhibitory afterdischarge in these mPFC subregions. Actions of ketamine on the LSN-mPFC connection reproduced actions of fluoxetine, consisting of accentuated inhibition of the LSN action on the mPFC. These findings suggest that independent of different actions on neurotransmission, the common final pathway of antidepressants lies in their actions on forebrain structures that are related to emotional regulation.


Asunto(s)
Fluoxetina , Ketamina , Corteza Prefrontal , Ratas Wistar , Núcleos Septales , Animales , Ketamina/farmacología , Fluoxetina/farmacología , Masculino , Corteza Prefrontal/efectos de los fármacos , Ratas , Núcleos Septales/efectos de los fármacos , Estimulación Eléctrica
16.
PLoS One ; 19(2): e0296851, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38330074

RESUMEN

BACKGROUND: At the beginning of the COVID-19 pandemic, non-pharmaceutical interventions (NPIs) of unprecedented scope and duration were implemented to limit community spread of COVID-19. There remains limited evidence about how these measures impacted the lived experience of affected communities. This study captured the early impacts and coping strategies implemented in King County, Washington, one of the first U.S. communities impacted by COVID-19. METHODS: We conducted a cross-sectional web-based survey of 793 English- and Spanish-speaking adult King County residents from March 18, 2020 -May 30, 2020, using voluntary response sampling. The survey included close- and open-ended questions on participant demographics, wellbeing, protective actions, and COVID-19-related concerns, including a freeform narrative response to describe the pandemic's individual-, family- and community-level impacts and associated coping strategies. Descriptive statistics were used to analyze close-ended questions, and qualitative content analysis methods were used to analyze free-form narrative responses. RESULTS: The median age of participants was 45 years old, and 74% were female, 82% were White, and 6% were Hispanic/Latinx; 474 (60%) provided a qualitative narrative. Quantitative findings demonstrated that higher percentages of participants engaged in most types of COVID-19 protective behaviors after the stay-at-home order was implemented and schools and community spaces were closed, relative to before, and that participants tended to report greater concern about the pandemic's physical health or healthcare access impacts than the financial or social impacts. Qualitative data analysis described employment or financial impacts (56%) and vitality coping strategies (65%), intended to support health or positive functioning. CONCLUSIONS: This study documented early impacts of the COVID-19 pandemic and the NPIs implemented in response, as well as strategies employed to cope with those impacts, which can inform early-stage policy formation and intervention strategies to mitigate the negative impacts. Future research should explore the endurance and evolution of the early impacts and coping strategies throughout the multiyear pandemic.


Asunto(s)
COVID-19 , Adulto , Humanos , Femenino , Persona de Mediana Edad , Masculino , COVID-19/epidemiología , COVID-19/prevención & control , Estudios Transversales , Pandemias/prevención & control , Cuarentena , Washingtón/epidemiología
17.
Arq Bras Cardiol ; 121(1): e20230537, 2024.
Artículo en Portugués, Inglés | MEDLINE | ID: mdl-38511808

RESUMEN

This case report describes the exercise program on a hospitalized 54-year-old male patient with cardiogenic shock waiting for a heart transplant assisted by an intra-aortic balloon pump, a temporary mechanical circulatory support device. The temporary mechanical circulatory support device, an intra-aortic balloon pump, was placed in the left subclavian artery, enabling the exercise protocol. Measurements and values from Swan-Ganz catheter, blood sample, brain natriuretic peptide (NT-proBNP), and high-sensitivity C-reactive protein (hs-CRP), as well as the six-minute walk test (6MWT) and venous oxygen saturation (SvO2) were obtained before and after an exercise protocol. The exercise training protocol involved the use of an unloaded bed cycle ergometer once a day, for a maximum of 30 minutes, to the tolerance limit. No adverse events or events related to the dislocation of the intra-aortic balloon pump were observed during the exercise protocol. The exercise program resulted in higher SvO2 levels, with an increased 6MWT with lower Borg dyspnea scores (312 meters vs. 488 meters and five points vs. three points, respectively). After completing the ten-day exercise protocol, the patient underwent a non-complicated heart transplant surgery and a full recovery in the ICU. This study showed that exercise is a feasible option for patients with cardiogenic shock who are using an intra-aortic balloon pump and that it is well-tolerated with no reported adverse events.


O presente relato de caso descreve o programa de exercícios aplicado a um paciente do sexo masculino, de 54 anos, internado com choque cardiogênico, aguardando transplante cardíaco e assistido por balão intra-aórtico, um dispositivo de suporte circulatório mecânico temporário. O dispositivo de suporte circulatório mecânico temporário, um balão intra-aórtico, foi colocado na artéria subclávia esquerda, possibilitando o protocolo de exercícios. Antes e após um protocolo de exercícios, foram obtidos dados a partir de cateter de Swan-Ganz, amostra de sangue, peptídeo natriurético cerebral (NT-proBNP), proteína C reativa de alta sensibilidade (PCR-as), teste de caminhada de seis minutos (TC6min) e medição da saturação venosa de oxigênio (SvO2). O protocolo de treinamento físico envolveu a utilização de um cicloergômetro adaptado ao leito, sem carga, uma vez ao dia, por no máximo 30 minutos, até o limite da tolerância. Não foram observados eventos adversos tampouco relacionados ao deslocamento do balão intra-aórtico durante o protocolo de exercícios. O programa de exercícios resultou em maior SvO2 com aumento do TC6min e menores escores de dispneia de Borg (312 metros vs. 488 metros e cinco pontos vs. três pontos, respectivamente). Após completar o protocolo de exercícios de dez dias, o paciente foi submetido a uma cirurgia de transplante cardíaco sem complicações e recuperação total na UTI. O presente estudo demonstrou que o exercício é uma opção viável para pacientes com choque cardiogênico em uso de balão intra-aórtico e que é bem tolerado, além de não haver relatos de eventos adversos.


Asunto(s)
Trasplante de Corazón , Corazón Auxiliar , Masculino , Humanos , Persona de Mediana Edad , Choque Cardiogénico/terapia , Choque Cardiogénico/etiología , Trasplante de Corazón/efectos adversos , Caminata , Contrapulsador Intraaórtico/efectos adversos , Contrapulsador Intraaórtico/métodos , Corazón Auxiliar/efectos adversos , Resultado del Tratamiento
18.
Behav Pharmacol ; 24(8): 693-8, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24196028

RESUMEN

The defensive burying test is an experimental model that is used to explore anxiety-like behavior in adult rats. Because the expression of anxiety-like behavior may differ between infant and adult rats, we tested the impact of chambers with different sizes and shapes on defensive burying in 28-day-old Wistar rats. The first two chambers had base areas of 560 cm, but one was rectangular and the other round. The base areas of the other two chambers were 282 cm, also with one rectangular and one round. We examined the effects of vehicle and 1 mg/kg diazepam on defensive burying in the various chambers. Locomotor activity was also measured to identify or exclude any sedative effects. Independent of the treatments used, the infant rats showed a shorter burying latency in the three modified chambers and a longer cumulative burying time compared with the original apparatus. The effects of diazepam (i.e. increased latency and decreased burying time) were only significant in the small round chamber, without significant effects on general motor activity. These results suggest that a small round chamber that is used to test burying behavior is sensitive to the anxiolytic actions of diazepam when the experimental subjects are very young rats.


Asunto(s)
Envejecimiento/fisiología , Conducta Animal/efectos de los fármacos , Diazepam/farmacología , Animales , Ansiolíticos/farmacología , Ansiedad/psicología , Modelos Animales de Enfermedad , Femenino , Masculino , Actividad Motora/efectos de los fármacos , Ratas , Ratas Wistar , Destete
19.
Dev Psychobiol ; 55(3): 221-31, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22315200

RESUMEN

In humans, maternal cues guide newborns to the maternal breast, and transitional cues may be present in maternal-fetal fluids. The aim of the present study was to determine the consistent presence of sensorial cues in three maternal-fetal fluids--amniotic fluid, colostrum, and milk--and test the ability of these cues to produce appetitive responses in newborns. In the analytical study, gas chromatography-mass spectrometry (GC-MS) detected eight fatty acids consistently present in the amniotic fluid, colostrum, and milk from 12 healthy volunteers, but we do not find a mammalian pheromone, identified in another mammalian species (rabbits), in another 30 volunteers. In the behavioral study, we explored the ability of amniotic fluid or its fatty acids to produce appetitive responses in 19 human newborns <24 hr after birth. Exposure to swabs impregnated with amniotic fluid or an artificial fatty acid mixture produced a longer duration of facial reactions that suggested appetitive (sucking) movements compared with respective vehicles (i.e., propylene glycol or centrifuged amniotic fluid with a low fatty acid content verified by GC-MS). We conclude that the fatty acids contained in amniotic fluid may constitute a transitional sensorial cue that guides newborns to the maternal breast.


Asunto(s)
Líquido Amniótico/química , Conducta Apetitiva/fisiología , Calostro/química , Ácidos Grasos/análisis , Recién Nacido/fisiología , Leche Humana/química , Feromonas Humanas/análisis , Adolescente , Adulto , Análisis de Varianza , Ácidos Grasos/fisiología , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos , Recién Nacido/psicología , Percepción Olfatoria/fisiología , Embarazo
20.
BMC Complement Altern Med ; 13: 329, 2013 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-24267469

RESUMEN

BACKGROUND: Sonoran ethnic groups (Yaquis, Mayos, Seris, Guarijíos, Pimas, Kikapúes and Pápagos) use mainly herbal based preparations as their first line of medicinal treatment. Among the plants used are those with anti-tuberculosis properties; however, no formal research is available. METHODS: Organic extracts were obtained from nine medicinal plants traditionally used by Sonoran ethnic groups to treat different kinds of diseases; three of them are mainly used to treat tuberculosis. All of the extracts were tested against Mycobacterium tuberculosis H37Rv using the Alamar Blue redox bioassay. RESULTS: Methanolic extracts from Ambrosia confertiflora, Ambrosia ambrosioides and Guaiacum coulteri showed minimal inhibitory concentration (MIC) values of 200, 790 and 1000 µg/mL, respectively, whereas no effect was observed with the rest of the methanolic extracts at the concentrations tested. Chloroform, dichloromethane, and ethyl acetate extracts from Ambrosia confertiflora showed a MIC of 90, 120 and 160 µg/mL, respectively. CONCLUSIONS: A. confertiflora and A. ambrosioides showed the best anti-mycobacterial activity in vitro. The activity of Guaiacum coulteri is consistent with the traditional use by Sonoran ethnic groups as anti-tuberculosis agent.For these reasons, it is important to investigate a broader spectrum of medicinal plants in order to find compounds active against Mycobacterium tuberculosis.


Asunto(s)
Antituberculosos/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Extractos Vegetales/farmacología , Plantas Medicinales/química , Medicina Tradicional , México , Pruebas de Sensibilidad Microbiana
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