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1.
Semin Dial ; 37(3): 228-233, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38099410

RESUMEN

BACKGROUND: The nutritional status of incident patients on peritoneal dialysis (PD) has been associated with survival outcomes. Bioimpedanciometry (BCM) enables to establish a nutritional diagnosis, the volume status, and correlates these findings with survival. METHODS: This study used a retrospective multicenter historical cohort. RESULTS: In this study, which included 420 incident patients on peritoneal dialysis with a 5-year follow-up, a cumulative incidence of major adverse cardiovascular events (MACE) of 28.8% was found, being higher in the diabetic population at 36.8%. In regard to the nutritional status in this population, it was found that approximately 44% had altered nutritional status; 34% were found to be in sarcopenia; 6.7% sarcopenic obesity; and 2.8% in obesity (p < 0.001). In the survival analysis, a lower probability of survival was found in patients with overhydration (OH) greater than 3 L (p < 0.001) and in patients with altered nutritional status due to sarcopenia, sarcopenic obesity, and obesity (p 0.016). According to survival in the subgroup of the diabetic population, a lower probability of survival was found in this group of patients (p: 0.011). The overall mortality of the study population was 18%, being higher in the first 2 years, with the most important causes of mortality being cardiovascular. Of the deceased population, 51% were diabetic patients (p: 0.012). CONCLUSION: In incident patients on peritoneal dialysis, sarcopenic obesity, sarcopenia, overhydration status determined by BCM, and having a diagnosis of diabetes are related to a lower probability of survival; MACE outcomes are more frequent in the diabetic population.


Asunto(s)
Enfermedades Cardiovasculares , Fallo Renal Crónico , Estado Nutricional , Diálisis Peritoneal , Humanos , Masculino , Femenino , Enfermedades Cardiovasculares/mortalidad , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/etiología , Persona de Mediana Edad , Estudios Retrospectivos , Incidencia , Fallo Renal Crónico/terapia , Fallo Renal Crónico/mortalidad , Fallo Renal Crónico/complicaciones , Colombia/epidemiología , Anciano , Adulto , Tasa de Supervivencia , Sarcopenia/epidemiología , Sarcopenia/diagnóstico , Sarcopenia/mortalidad , Sarcopenia/etiología
2.
J Appl Microbiol ; 135(1)2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38126104

RESUMEN

AIM: To assess the effectiveness of Bacillus subtilis strain LN8B as a biocollector for recovering pyrite (Py) and chalcopyrite (CPy) in both seawater (Sw) and deionized water (Dw), and to explore the underlying adhesion mechanism in these bioflotation experiments. MATERIALS AND METHODS: The bioflotation test utilized B. subtilis strain LN8B as the biocollector through microflotation experiments. Additionally, frother methyl isobutyl carbinol (MIBC) and conventional collector potassium amyl xanthate (PAX) were introduced in some experiments. The zeta potential (ZP) and Fourier-transform infrared spectroscopy (FTIR) was employed to explore the adhesion mechanism of Py and CPy interacting with the biocollector in Sw and Dw. The adaptability of the B. subtilis strain to different water types and salinities was assessed through growth curves measuring optical density. Finally, antibiotic susceptibility tests were conducted to evaluate potential risks of the biocollector. RESULTS: Superior outcomes were observed in Sw where Py and CPy recovery was ∼39.3% ± 7.7% and 41.1% ± 5.8%, respectively, without microorganisms' presence. However, B. subtilis LN8B potentiate Py and CPy recovery, reaching 72.8% ± 4.9% and 84.6% ± 1.5%, respectively. When MIBC was added, only the Py recovery was improved (89.4% ± 3.6%), depicting an adverse effect for CPy (81.8% ± 1.1%). ZP measurements indicated increased mineral surface hydrophobicity when Py and CPy interacted with the biocollector in both Sw and Dw. FTIR revealed the presence of protein-related amide peaks, highlighting the hydrophobic nature of the bacterium. The adaptability of this strain to diverse water types and salinities was assessed, demonstrating remarkable growth versatility. Antibiotic susceptibility tests indicated that B. subtilis LN8B was susceptible to 23 of the 25 antibiotics examined, suggesting it poses minimal environmental risks. CONCLUSIONS: The study substantiates the biotechnological promise of B. subtilis strain LN8B as an efficient sulfide collector for promoting cleaner mineral production. This effectiveness is attributed to its ability to induce mineral surface hydrophobicity, a result of the distinct characteristics of proteins within its cell wall.


Asunto(s)
Bacillus subtilis , Cobre , Hierro , Minerales , Bacillus subtilis/metabolismo , Agua de Mar , Sulfuros/farmacología , Sulfuros/metabolismo , Agua/metabolismo , Antibacterianos/farmacología , Antibacterianos/metabolismo
3.
Dermatol Online J ; 30(1)2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38762866

RESUMEN

Milia en plaque (MEP) is an uncommon skin condition identified as retroauricular confluent milium by Boulzer and Fouqet in 1903 [1]. It can be mistaken for other dermatoses like Favre-Racouchot nodular elastosis, steatocystoma multiplex, and nevus comedonicus. Milia en plaque can either be primary or secondary and is typically benign, often triggered by dermatological procedures like cryotherapy, as reported in this journal. In some cases, MEP can arise as a secondary manifestation of other diseases, including folliculotropic mycosis fungoides (FMF). Despite this association, there are few documented cases in the literature. Herein, we present a patient in whom MEP served as the initial clinical presentation of FMF; the treatment involved oral retinoids and phototherapy. Furthermore, we highlight distinctive features of both conditions. It is important to emphasize that early diagnosis and treatment of FMF are vital for the patient's quality of life. The presence of MEP can serve as a valuable indicator for identifying it.


Asunto(s)
Micosis Fungoide , Neoplasias Cutáneas , Humanos , Micosis Fungoide/patología , Micosis Fungoide/diagnóstico , Micosis Fungoide/complicaciones , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/complicaciones , Hombro , Masculino , Persona de Mediana Edad , Femenino , Retinoides/uso terapéutico , Diagnóstico Diferencial , Queratosis
4.
Mol Biol Rep ; 50(12): 10367-10382, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37817022

RESUMEN

SARS-CoV-2, a novel coronavirus within the Coronaviridae family, is the causative agent behind the respiratory ailment referred to as COVID-19. Operating on a global scale, COVID-19 has led to a substantial number of fatalities, exerting profound effects on both public health and the global economy. The most frequently reported symptoms encompass fever, cough, muscle or body aches, loss of taste or smell, headaches, and fatigue. Furthermore, a subset of individuals may manifest more severe symptoms, including those consistent with viral pneumonitis, which can be so profound as to result in fatalities. Consequently, this situation has spurred the rapid advancement of disease diagnostic technologies worldwide. Predominantly employed in diagnosing COVID-19, the real-time quantitative reverse transcription PCR has been the foremost diagnostic method, effectively detecting SARS-CoV-2 viral RNA. As the pandemic has evolved, antigen and serological tests have emerged as valuable diagnostic tools. Antigen tests pinpoint specific viral proteins of SARS-CoV-2, offering swift results, while serological tests identify the presence of antibodies in blood samples. Additionally, there have been notable strides in sample collection methods, notably with the introduction of saliva-based tests, presenting a non-invasive substitute to nasopharyngeal swabs. Given the ongoing mutations in SARS-CoV-2, there has been a continuous need for genomic surveillance, encompassing full genome sequencing and the identification of new variants through Illumina technology and, more recently, nanopore metagenomic sequencing (SMTN). Consequently, while diagnostic testing methods for COVID-19 have experienced remarkable progress, no test is flawless, and there exist limitations with each technique, including sensitivity, specificity, sample collection, and the minimum viral load necessary for accurate detection. These aspects are comprehensively addressed within this current review.


Asunto(s)
COVID-19 , Neumonía Viral , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , Patología Molecular , Neumonía Viral/diagnóstico , ARN Viral/genética , Sensibilidad y Especificidad , Prueba de COVID-19
5.
Environ Res ; 218: 114904, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36502904

RESUMEN

Operations in copper sulfide flotation plants (CSFP) are complex and governed by several variables such as available technologies, reagents, and environmental conditions. However, few investigations are related to studying the microbial communities. These aspects provide a reason to compare the bacterial communities of two CSFP operated with freshwater (FwFlo) and seawater (SwFlo), and study whether indigenous bacteria could be used as pyrite bioreagents. Analyses were determined through next-generation sequencing by Illumina MiSeq System and conducted throughout the entire process: (i) minerals before and after grinding; (ii) final concentrate and concentrate thickener overflow; (iii) final tailings and tailings thickener overflow; and (iv) intake water. Bacterial strains from both plants were tested as potential bioreagents, given their tendency to adhere to pyrite after 5 min. In both CSFP, Proteobacteria (relative abundance from 45.48% to 79.22%), followed by Bacteroidetes (9.37%-44.7%), were the most abundant phyla. Regarding species, Algoriphagus olei (11.35%-43.52%) was present exclusively in FwFlo samples in contact with process water and absent in the mineral before grinding, where Cupriavidus metallidurans (16.05%) and Pseudomonas_uc (11.79%) predominated. In SwFlo samples, Marinobacter flavimaris (3.47%-41.1%), and GU061212-s (10.92%-27.63%), were the most abundant microorganisms. All of them were also detected in intake seawater. The strains with the highest adhesion rate (from 29.84% ± 0.14-100%) were phylogenetically identified as species of the genera Marinobacter, Pseudomonas, Idiomarina, Halomonas, Bacillus, Aerocuccus, and Peribacillus. Our results reveal that bacterial communities are critically dependent on process waters during mining activities, and our data depicted that indigenous bacteria could be used as potential pyrite bioreagents, evidenced by a high adhesion rate. It is thus possible to propose that different indigenous bacterial strains could be considered as new bioreagents to reduce the impact of conventional flotation reagents on health from an environment friendly perspective.


Asunto(s)
Bacterias , Cobre , Bacterias/genética , Sulfuros , Minerales , Agua
6.
Opt Lett ; 47(4): 810-813, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-35167531

RESUMEN

Integrated mid-infrared micro-spectrometers have a great potential for applications in environmental monitoring and space exploration. Silicon-on-insulator (SOI) is a promising platform to tackle this integration challenge, owing to its unique capability for large volume and low-cost production of ultra-compact photonic circuits. However, the use of SOI in the mid-infrared is restricted by the strong absorption of the buried oxide layer for wavelengths beyond 4 µm. Here, we overcome this limitation by utilizing metamaterial-cladded suspended silicon waveguides to implement a spatial heterodyne Fourier-transform (SHFT) spectrometer operating at wavelengths near 5.5 µm. The metamaterial-cladded geometry allows removal of the buried oxide layer, yielding measured propagation loss below 2 dB/cm at wavelengths between 5.3 and 5.7 µm. The SHFT spectrometer comprises 19 Mach-Zehnder interferometers with a maximum arm length imbalance of 200 µm, achieving a measured spectral resolution of 13 cm-1 and a free spectral range of 100 cm-1 at wavelengths near 5.5 µm.

7.
Nature ; 534(7606): 267-71, 2016 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-27279226

RESUMEN

Zika virus (ZIKV) is an arbovirus belonging to the genus Flavivirus (family Flaviviridae) and was first described in 1947 in Uganda following blood analyses of sentinel Rhesus monkeys. Until the twentieth century, the African and Asian lineages of the virus did not cause meaningful infections in humans. However, in 2007, vectored by Aedes aegypti mosquitoes, ZIKV caused the first noteworthy epidemic on the Yap Island in Micronesia. Patients experienced fever, skin rash, arthralgia and conjunctivitis. From 2013 to 2015, the Asian lineage of the virus caused further massive outbreaks in New Caledonia and French Polynesia. In 2013, ZIKV reached Brazil, later spreading to other countries in South and Central America. In Brazil, the virus has been linked to congenital malformations, including microcephaly and other severe neurological diseases, such as Guillain-Barré syndrome. Despite clinical evidence, direct experimental proof showing that the Brazilian ZIKV (ZIKV(BR)) strain causes birth defects remains absent. Here we demonstrate that ZIKV(BR) infects fetuses, causing intrauterine growth restriction, including signs of microcephaly, in mice. Moreover, the virus infects human cortical progenitor cells, leading to an increase in cell death. We also report that the infection of human brain organoids results in a reduction of proliferative zones and disrupted cortical layers. These results indicate that ZIKV(BR) crosses the placenta and causes microcephaly by targeting cortical progenitor cells, inducing cell death by apoptosis and autophagy, and impairing neurodevelopment. Our data reinforce the growing body of evidence linking the ZIKV(BR) outbreak to the alarming number of cases of congenital brain malformations. Our model can be used to determine the efficiency of therapeutic approaches to counteracting the harmful impact of ZIKV(BR) in human neurodevelopment.


Asunto(s)
Modelos Animales de Enfermedad , Microcefalia/virología , Virus Zika/patogenicidad , Animales , Apoptosis , Autofagia , Encéfalo/patología , Encéfalo/virología , Brasil/epidemiología , Proliferación Celular , Femenino , Retardo del Crecimiento Fetal/patología , Retardo del Crecimiento Fetal/virología , Feto/virología , Ratones , Microcefalia/epidemiología , Microcefalia/etiología , Microcefalia/patología , Células-Madre Neurales/patología , Células-Madre Neurales/virología , Organoides/patología , Organoides/virología , Placenta/virología , Embarazo , Infección por el Virus Zika/complicaciones , Infección por el Virus Zika/epidemiología , Infección por el Virus Zika/patología , Infección por el Virus Zika/virología
8.
Biol Res ; 55(1): 37, 2022 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-36461078

RESUMEN

BACKGROUND: Diabetes mellitus (DM) has glucose variability that is of such relevance that the appearance of vascular complications in patients with DM has been attributed to hyperglycemic and dysglycemic events. It is known that T1D patients mainly have glycemic variability with a specific oscillatory pattern with specific circadian characteristics for each patient. However, it has not yet been determined whether an oscillation pattern represents the variability of glycemic in T2D. This is why our objective is to determine the characteristics of glycemic oscillations in T2D and generate a robust predictive model. RESULTS: Showed that glycosylated hemoglobin, glycemia, and body mass index were all higher in patients with T2D than in controls (all p < 0.05). In addition, time in hyperglycemia and euglycemia was markedly higher and lower in the T2D group (p < 0.05), without significant differences for time in hypoglycemia. Standard deviation, coefficient of variation, and total power of glycemia were significantly higher in the T2D group than Control group (all p < 0.05). The oscillatory patterns were significantly different between groups (p = 0.032): the control group was mainly distributed at 2-3 and 6 days, whereas the T2D group showed a more homogeneous distribution across 2-3-to-6 days. CONCLUSIONS: The predictive model of glycemia showed that it is possible to accurately predict hyper- and hypoglycemia events. Thus, T2D patients exhibit specific oscillatory patterns of glycemic control, which are possible to predict. These findings may help to improve the treatment of DM by considering the individual oscillatory patterns of patients.


Asunto(s)
Diabetes Mellitus Tipo 2 , Hipoglucemia , Humanos , Diabetes Mellitus Tipo 2/complicaciones , Glucemia , Glucosa
9.
Sensors (Basel) ; 22(2)2022 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-35062433

RESUMEN

BACKGROUND: This systematic review aimed to assess the effectiveness and safety of aPDT for the treatment of halitosis. METHODS: Search strategies were conducted in October 2021 without language or data restrictions, on the following databases: MEDLINE, EMBASE, CENTRAL, LILACS and BBO, as well as a manual search. Randomized clinical trials (RCTs) with parallel design were considered for inclusion, assessing individuals (adolescents and adults) with a clinical diagnosis of halitosis treated with photodynamic therapy (aPDT). Primary outcomes assessed were halitosis measurements, adverse events and quality of life. The risk of bias for each included study was evaluated with the Cochrane Risk of Bias tool and the certainty of the body of the evidence was assessed with the GRADe approach. RESULTS: Six RCTs (total of 225 participants) were included and due to clinical diversities it was not possible to group the outcome data in meta-analyses. Based on very low-certainty evidence (GRADE) the results showed that, when compared to tongue scraper, aPDT seems to promote a little to no difference in reducing halitosis and in the microbiological analysis. No adverse events were reported. Considering aPDT combined with tongue scraper, better outcome results were observed when compared to tongue scraper alone. CONCLUSIONS: Based on very low-certainty evidence, the findings of this review are uncertain about the effects of aPDT for halitosis control. Further RCTs with higher number of participants and long term assessments need to be conducted to support the use of this intervention. The protocol was registered in the PROSPERO database (number: CRD42020215319) on 19 November 2020-retrospectively registered.


Asunto(s)
Halitosis , Fotoquimioterapia , Adolescente , Adulto , Halitosis/diagnóstico , Halitosis/tratamiento farmacológico , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto
10.
Am J Physiol Heart Circ Physiol ; 320(4): H1498-H1509, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33513085

RESUMEN

Paraquat (PQT) herbicide is widely used in agricultural practices despite being highly toxic to humans. It has been proposed that PQT exposure may promote cardiorespiratory impairment. However, the physiological mechanisms involved in cardiorespiratory dysfunction following PQT exposure are poorly known. We aimed to determine the effects of PQT on ventilatory chemoreflex control, cardiac autonomic control, and cardiac function in rats. Male Sprague-Dawley rats received two injections/week of PQT (5 mg·kg-1 ip) for 4 wk. Cardiac function was assessed through echocardiography and pressure-volume loops. Ventilatory function was evaluated using whole body plethysmography. Autonomic control was indirectly evaluated by heart rate variability (HRV). Cardiac electrophysiology (EKG) and exercise capacity were also measured. Four weeks of PQT administration markedly enlarged the heart as evidenced by increases in ventricular volumes and induced cardiac diastolic dysfunction. Indeed, end-diastolic pressure was significantly higher in PQT rats compared with control (2.42 ± 0.90 vs. 4.01 ± 0.92 mmHg, PQT vs. control, P < 0.05). In addition, PQT significantly reduced both the hypercapnic and hypoxic ventilatory chemoreflex response and induced irregular breathing. Also, PQT induced autonomic imbalance and reductions in the amplitude of EKG waves. Finally, PQT administration impaired exercise capacity in rats as evidenced by a ∼2-fold decrease in times-to-fatigue compared with control rats. Our results showed that 4 wk of PQT treatment induces cardiorespiratory dysfunction in rats and suggests that repetitive exposure to PQT may induce harmful mid/long-term cardiovascular, respiratory, and cardiac consequences.NEW & NOREWORTHY Paraquat herbicide is still employed in agricultural practices in several countries. Here, we showed for the first time that 1 mo paraquat administration results in cardiac adverse remodeling, blunts ventilatory chemoreflex drive, and promotes irregular breathing at rest in previously healthy rats. In addition, paraquat exposure induced cardiac autonomic imbalance and cardiac electrophysiology alterations. Lastly, cardiac diastolic dysfunction was overt in rats following 1 mo of paraquat treatment.


Asunto(s)
Arritmias Cardíacas/inducido químicamente , Sistema Nervioso Autónomo/efectos de los fármacos , Células Quimiorreceptoras/efectos de los fármacos , Frecuencia Cardíaca/efectos de los fármacos , Corazón/inervación , Herbicidas/toxicidad , Hipertrofia Ventricular Izquierda/inducido químicamente , Pulmón/inervación , Paraquat/toxicidad , Ventilación Pulmonar/efectos de los fármacos , Reflejo/efectos de los fármacos , Animales , Arritmias Cardíacas/metabolismo , Arritmias Cardíacas/fisiopatología , Sistema Nervioso Autónomo/fisiopatología , Células Quimiorreceptoras/metabolismo , Tolerancia al Ejercicio/efectos de los fármacos , Hipertrofia Ventricular Izquierda/metabolismo , Hipertrofia Ventricular Izquierda/fisiopatología , Masculino , Ratas Sprague-Dawley , Función Ventricular Izquierda/efectos de los fármacos , Remodelación Ventricular/efectos de los fármacos
11.
Opt Lett ; 46(16): 4021-4024, 2021 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-34388801

RESUMEN

Integrated microspectrometers implemented in silicon photonic chips have gathered a great interest for diverse applications such as biological analysis, environmental monitoring, and remote sensing. These applications often demand high spectral resolution, broad operational bandwidth, and large optical throughput. Spatial heterodyne Fourier-transform (SHFT) spectrometers have been proposed to overcome the limited optical throughput of dispersive and speckle-based on-chip spectrometers. However, state-of-the-art SHFT spectrometers in near-infrared achieve large optical throughput only within a narrow operational bandwidth. Here we demonstrate for the first time, to the best of our knowledge, a broadband silicon nitride SHFT spectrometer with the largest light collecting multiaperture input (320×410µm2) ever implemented in an SHFT on-chip spectrometer. The device was fabricated using 248 nm deep-ultraviolet lithography, exhibiting over 13 dB of optical throughput improvement compared to a single-aperture device. The measured resolution varies between 29 and 49 pm within the 1260-1600 nm wavelength range.

12.
Opt Lett ; 46(6): 1341-1344, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33720182

RESUMEN

Silicon photonics on-chip spectrometers are finding important applications in medical diagnostics, pollution monitoring, and astrophysics. Spatial heterodyne Fourier transform spectrometers (SHFTSs) provide a particularly interesting architecture with a powerful passive error correction capability and high spectral resolution. Despite having an intrinsically large optical throughput (étendue, also referred to as Jacquinot's advantage), state-of-the-art silicon SHFTSs have not exploited this advantage yet. Here, we propose and experimentally demonstrate for the first time, to the best of our knowledge, an SHFTS implementing a wide-area light collection system simultaneously feeding an array of 16 interferometers, with an input aperture as large as 90µm×60µm formed by a two-way-fed grating coupler. We experimentally demonstrate 85 pm spectral resolution, 600 pm bandwidth, and 13 dB étendue increase, compared with a device with a conventional grating coupler input. The SHFTS was fabricated using 193 nm deep-UV optical lithography and integrates a large-size input aperture with an interferometer array and monolithic Ge photodetectors, in a 4.5mm2 footprint.

13.
Opt Lett ; 46(3): 617-620, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33528423

RESUMEN

Surface grating couplers are fundamental building blocks for coupling the light between optical fibers and integrated photonic devices. However, the operational bandwidth of conventional grating couplers is intrinsically limited by their wavelength-dependent radiation angle. The few dual-band grating couplers that have been experimentally demonstrated exhibit low coupling efficiencies and rely on complex fabrication processes. Here we demonstrate for the first time, to the best of our knowledge, the realization of an efficient dual-band grating coupler fabricated using 193 nm deep-ultraviolet lithography for 10 Gbit symmetric passive optical networks. The footprint of the device is 17×10µm2. We measured coupling efficiencies of -4.9 and -5.2dB with a 3-dB bandwidth of 27 and 56 nm at the wavelengths of 1270 and 1577 nm, corresponding to the upstream and downstream channels, respectively.

14.
Biol Res ; 54(1): 32, 2021 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-34565477

RESUMEN

BACKGROUND: Deep breathing (DB) and handgrip (HG) exercise -with and without circulatory occlusion (OC) in muscle-, have been shown to have beneficial effects on cardiovascular function; however, the combination of these maneuvers on heart rate (HR) and cardiac sympathovagal balance have not been previously investigated. Therefore, the aim of the present study was to evaluate the effect of simultaneous DB, HG, and OC maneuvers on the sympathovagal balance in healthy women and men subjects. METHODS AND RESULTS: Electrocardiogram and ventilation were measured in 20 healthy subjects (Women: n = 10; age = 27 ± 4 years; weight = 67.1 ± 8.4 kg; and height = 1.6 ± 0.1 m. Men: n = 10; age = 27 ± 3 years; weight = 77.5 ± 10.1 kg; and height = 1.7 ± 0.1 m) at baseline and during DB, DB + HG, or DB + HG + OC protocols. Heart rate (HR) and respiratory rate were continuously recorded, and spectral analysis of heart rate variability (HRV) were calculated to indirectly estimate cardiac autonomic function. Men and women showed similar HR responses to DB, DB + HG and DB + HG + OC. Men exhibited a significant HR decrease following DB + HG + OC protocol which was accompanied by an improvement in cardiac autonomic control evidenced by spectral changes in HRV towards parasympathetic predominance (HRV High frequency: 83.95 ± 1.45 vs. 81.87 ± 1.50 n.u., DB + HG + OC vs. baseline; p < 0.05). In women, there was a marked decrease in HR after completion of both DB + HG and DB + HG + OC tests which was accompanied by a significant increase in cardiac vagal tone (HRV High frequency: 85.29 ± 1.19 vs. 77.93 ± 0.92 n.u., DB + HG vs. baseline; p < 0.05). No adverse effects or discomfort were reported by men or women during experimental procedures. Independent of sex, combination of DB, HG, and OC was tolerable and resulted in decreases in resting HR and elevations in cardiac parasympathetic tone. CONCLUSIONS: These data indicate that combined DB, HG and OC are effective in altering cardiac sympathovagal balance and reducing resting HR in healthy men and women.


Asunto(s)
Sistema Nervioso Autónomo , Fuerza de la Mano , Adulto , Femenino , Frecuencia Cardíaca , Humanos , Masculino , Adulto Joven
15.
Biol Res ; 54(1): 43, 2021 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-34952651

RESUMEN

BACKGROUND: Chronic heart failure (CHF) is a global health problem. Increased sympathetic outflow, cardiac arrhythmogenesis and irregular breathing patterns have all been associated with poor outcomes in CHF. Several studies showed that activation of the renin-angiotensin system (RAS) play a key role in CHF pathophysiology. Interestingly, potassium (K+) supplemented diets showed promising results in normalizing RAS axis and autonomic dysfunction in vascular diseases, lowering cardiovascular risk. Whether subtle increases in dietary K+ consumption may exert similar effects in CHF has not been previously tested. Accordingly, we aimed to evaluate the effects of dietary K+ supplementation on cardiorespiratory alterations in rats with CHF. METHODS: Adult male Sprague-Dawley rats underwent volume overload to induce non-ischemic CHF. Animals were randomly allocated to normal chow diet (CHF group) or supplemented K+ diet (CHF+K+ group) for 6 weeks. Cardiac arrhythmogenesis, sympathetic outflow, baroreflex sensitivity, breathing disorders, chemoreflex function, respiratory-cardiovascular coupling and cardiac function were evaluated. RESULTS: Compared to normal chow diet, K+ supplemented diet in CHF significantly reduced arrhythmia incidence (67.8 ± 15.1 vs. 31.0 ± 3.7 events/hour, CHF vs. CHF+K+), decreased cardiac sympathetic tone (ΔHR to propranolol: - 97.4 ± 9.4 vs. - 60.8 ± 8.3 bpm, CHF vs. CHF+K+), restored baroreflex function and attenuated irregular breathing patterns. Additionally, supplementation of the diet with K+ restores normal central respiratory chemoreflex drive and abrogates pathological cardio-respiratory coupling in CHF rats being the outcome an improved cardiac function. CONCLUSION: Our findings support that dietary K+ supplementation in non-ischemic CHF alleviate cardiorespiratory dysfunction.


Asunto(s)
Insuficiencia Cardíaca , Animales , Dieta , Corazón , Masculino , Potasio , Ratas , Ratas Sprague-Dawley
16.
J Sports Sci ; 39(18): 2030-2050, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33956587

RESUMEN

This systematic review and meta-analysis aimed to assess the effects of jump training (JT) on measures of physical fitness and athletic performances in endurance runners. Controlled studies which involved healthy endurance runners, of any age and sex, were considered. A random-effects model was used to calculate effect sizes (ES; Hedge's g). Means and standard deviations of outcomes were converted to ES with alongside 95% confidence intervals (95%CI). Twenty-one moderate-to-high quality studies were included in the meta-analysis, and these included 511 participants. The main analyses revealed a significant moderate improvement in time-trial performance (i.e. distances between 2.0 and 5.0 km; ES = 0.88), without enhancements in maximal oxygen consumption (VO2max), velocity at VO2max, velocity at submaximal lactate levels, heart rate at submaximal velocities, stride rate at submaximal velocities, stiffness, total body mass or maximal strength performance. However, significant small-to-moderate improvements were noted for jump performance, rate of force development, sprint performance, reactive strength, and running economy (ES = 0.36-0.73; p < 0.001 to 0.031; I2 = 0.0% to 49.3%). JT is effective in improving physical fitness and athletic performance in endurance runners. Improvements in time-trial performance after JT may be mediated through improvements in force generating capabilities and running economy.


Asunto(s)
Rendimiento Atlético/fisiología , Resistencia Física/fisiología , Aptitud Física/fisiología , Ejercicio Pliométrico/métodos , Carrera/fisiología , Humanos
17.
J Physiol ; 598(1): 33-59, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31671478

RESUMEN

Heart failure (HF) is a complex clinical syndrome affecting roughly 26 million people worldwide. Increased sympathetic drive is a hallmark of HF and is associated with disease progression and higher mortality risk. Several mechanisms contribute to enhanced sympathetic activity in HF, but these pathways are still incompletely understood. Previous work suggests that inflammation and activation of the renin-angiotensin system (RAS) increases sympathetic drive. Importantly, chronic inflammation in several brain regions is commonly observed in aged populations, and a growing body of evidence suggests neuroinflammation plays a crucial role in HF. In animal models of HF, central inhibition of RAS and pro-inflammatory cytokines normalizes sympathetic drive and improves cardiac function. The precise molecular and cellular mechanisms that lead to neuroinflammation and its effect on HF progression remain undetermined. This review summarizes the most recent advances in the field of neuroinflammation and autonomic control in HF. In addition, it focuses on cellular and molecular mediators of neuroinflammation in HF and in particular on brain regions involved in sympathetic control. Finally, we will comment on what is known about neuroinflammation in the context of preserved vs. reduced ejection fraction HF.


Asunto(s)
Sistema Nervioso Autónomo/fisiopatología , Insuficiencia Cardíaca/fisiopatología , Inflamación/fisiopatología , Anciano , Animales , Humanos , Sistema Renina-Angiotensina , Disfunción Ventricular Izquierda
18.
Am J Physiol Lung Cell Mol Physiol ; 318(1): L27-L40, 2020 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-31617729

RESUMEN

Enhanced central chemoreflex (CC) gain is observed in volume overload heart failure (HF) and is correlated with autonomic dysfunction and breathing disorders. The aim of this study was to determine the role of the CC in the development of respiratory and autonomic dysfunction in HF. Volume overload was surgically created to induce HF in male Sprague-Dawley rats. Radiotelemetry transmitters were implanted for continuous monitoring of blood pressure and heart rate. After recovering from surgery, conscious unrestrained rats were exposed to episodic hypercapnic stimulation [EHS; 10 cycles/5 min, inspiratory fraction of carbon dioxide (FICO2) 7%] in a whole body plethysmograph for recording of cardiorespiratory function. To determine the contribution of CC to cardiorespiratory variables, selective ablation of chemoreceptor neurons within the retrotrapezoid nucleus (RTN) was performed via injection of saporin toxin conjugated to substance P (SSP-SAP). Vehicle-treated rats (HF+Veh and Sham+Veh) were used as controls for SSP-SAP experiments. Sixty minutes post-EHS, minute ventilation was depressed in sham animals relative to HF animals (ΔV̇e: -5.55 ± 2.10 vs. 1.24 ± 1.35 mL/min 100 g, P < 0.05; Sham+Veh vs. HF+Veh). Furthermore, EHS resulted in autonomic imbalance, cardiorespiratory entrainment, and ventilatory disturbances in HF+Veh but not Sham+Veh rats, and these effects were significantly attenuated by SSP-SAP treatment. Also, the apnea-hypopnea index (AHI) was significantly lower in HF+SSP-SAP rats compared with HF+Veh rats (AHI: 5.5 ± 0.8 vs. 14.4 ± 1.3 events/h, HF+SSP-SAP vs. HF+Veh, respectively, P < 0.05). Finally, EHS-induced respiratory-cardiovascular coupling in HF rats depends on RTN chemoreceptor neurons because it was reduced by SSP-SAP treatment. Overall, EHS triggers ventilatory plasticity and elicits cardiorespiratory abnormalities in HF that are largely dependent on RTN chemoreceptor neurons.


Asunto(s)
Enfermedades del Sistema Nervioso Autónomo/fisiopatología , Sistema Nervioso Central/fisiopatología , Células Quimiorreceptoras/metabolismo , Insuficiencia Cardíaca/fisiopatología , Neuronas/fisiología , Trastornos Respiratorios/fisiopatología , Animales , Enfermedades del Sistema Nervioso Autónomo/metabolismo , Presión Sanguínea/fisiología , Sistema Nervioso Central/metabolismo , Insuficiencia Cardíaca/metabolismo , Frecuencia Cardíaca/fisiología , Hipercapnia/metabolismo , Hipercapnia/fisiopatología , Masculino , Neuronas/metabolismo , Ratas , Ratas Sprague-Dawley , Respiración , Trastornos Respiratorios/metabolismo
19.
J Strength Cond Res ; 34(12): 3395-3402, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28820857

RESUMEN

Andrade, DC, Manzo, O, Beltrán, AR, Álvarez, C, Del Rio, R, Toledo, C, Moran, J, and Ramirez-Campillo, R. Kinematic and neuromuscular measures of intensity during plyometric jumps. J Strength Cond Res 34(12): 3395-3402, 2020-The aim of this study was to assess jumping performance and neuromuscular activity in lower limb muscles after drop jumps (DJs) from different drop heights (intensity) and during continuous jumping (fatigue), using markers such as reactive strength, jump height, mechanical power and surface electromyography (sEMG). The eccentric (EC) and concentric (CON) sEMG from the medial gastrocnemius (MG), biceps femoris (BF), and rectus (R) muscles were assessed during all tests. In a cross-sectional, randomized study, 11 volleyball players (age 24.4 ± 3.2 years) completed 20-90-cm (DJ20 to DJ90) DJs and a 60-second continuous jump test. A 1-way analysis of variance test was used for comparisons, with Sidak post hoc. The α level was <0.05. Reactive strength was greater for DJ40 compared with DJ90 (p ≤ 0.05; effect size (ES): 1.27). In addition, jump height was greater for DJ40 and DJ60 compared with DJ20 (p ≤ 0.05; ES: 1.26 and 1.27, respectively). No clear pattern of neuromuscular activity appeared during DJ20 to DJ90: some muscles showed greater, lower, or no change with increasing heights for both agonist and antagonist muscles, as well as for EC and CON activity. Mechanical power, but not reactive strength, was reduced in the 60-second jump test (p ≤ 0.05; ES: 3.46). No changes were observed in sEMG for any muscle during the EC phase nor for the R muscle during the CON phase of the 60-second jump test. However, for both MG and BF, CON sEMG was reduced during the 60-second jump test (p ≤ 0.05; ES: 5.10 and 4.61, respectively). In conclusion, jumping performance and neuromuscular markers are sensitive to DJ height (intensity), although not in a clear dose-response fashion. In addition, markers such as mechanical power and sEMG are, especially sensitive to the effects of continuous jumping (fatigue). Therefore, increasing the drop height during DJ does not ensure a greater training intensity and a combination of different drop heights may be required to elicit adaptations.


Asunto(s)
Extremidad Inferior/fisiología , Fuerza Muscular/fisiología , Músculo Esquelético/fisiología , Ejercicio Pliométrico/métodos , Adaptación Fisiológica , Adulto , Fenómenos Biomecánicos , Estudios Transversales , Electromiografía , Humanos , Masculino , Fatiga Muscular/fisiología , Adulto Joven
20.
J Sports Sci Med ; 19(3): 489-499, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32874101

RESUMEN

This meta-analysis aimed to assess the effects of plyometric jump training (PJT) on volleyball players' vertical jump height (VJH), comparing changes with those observed in a matched control group. A literature search in the databases of PubMed, MEDLINE, Web of Science, and SCOPUS was conducted. Only randomized-controlled trials and studies that included a pre-to-post intervention assessment of VJH were included. They involved only healthy volleyball players with no restrictions on age or sex. Data were independently extracted from the included studies by two authors. The Physiotherapy Evidence Database scale was used to assess the risk of bias, and methodological quality, of eligible studies included in the review. From 7,081 records, 14 studies were meta-analysed. A moderate Cohen's d effect size (ES = 0.82, p <0.001) was observed for VJH, with moderate heterogeneity (I2 = 34.4%, p = 0.09) and no publication bias (Egger's test, p = 0.59). Analyses of moderator variables revealed no significant differences for PJT program duration (≤8 vs. >8 weeks, ES = 0.79 vs. 0.87, respectively), frequency (≤2 vs. >2 sessions/week, ES = 0.83 vs. 0.78, respectively), total number of sessions (≤16 vs. >16 sessions, ES = 0.73 vs. 0.92, respectively), sex (female vs. male, ES = 1.3 vs. 0.5, respectively), age (≥19 vs. <19 years of age, ES = 0.89 vs. 0.70, respectively), and volume (>2,000 vs. <2,000 jumps, ES = 0.76 vs. 0.79, respectively). In conclusion, PJT appears to be effective in inducing improvements in volleyball players' VJH. Improvements in VJH may be achieved by both male and female volleyball players, in different age groups, with programs of relatively low volume and frequency. Though PJT seems to be safe for volleyball players, it is recommended that an individualized approach, according to player position, is adopted with some players (e.g. libero) less prepared to sustain PJT loads.


Asunto(s)
Rendimiento Atlético/fisiología , Ejercicio Pliométrico , Voleibol/fisiología , Femenino , Humanos , Masculino , Ejercicio Pliométrico/métodos , Ensayos Clínicos Controlados Aleatorios como Asunto , Factores Sexuales
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