Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 28
Filtrar
Más filtros

Tipo del documento
Intervalo de año de publicación
1.
Molecules ; 25(19)2020 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-33003282

RESUMEN

This study evaluates the photosensitizing effectiveness of sodium copper chlorophyllin, a natural green colorant commonly used as a food additive (E-141ii), to inactivate methicillin-sensitive and methicillin-resistant Staphylococcus aureus under red-light illumination. Antimicrobial photodynamic inactivation (aPDI) was tested on a methicillin-sensitive reference strain (ATCC 25923) and a methicillin-resistant Staphylococcus aureus strain (GenBank accession number Mh087437) isolated from a clinical sample. The photoinactivation efficacy was investigated by exposing the bacterial strains to different E-141ii concentrations (0.0, 1.0, 2.5, 5.0, 10.0, and 20.0 µM) and to red light (625 nm) at 30 J cm-2. The results showed that E-141ii itself did not prevent bacterial growth for all tested concentrations when cultures were placed in the dark. By contrast, E-141ii photoinactivated both methicillin-sensitive Staphylococcus aureus (MSSA) and methicillin-resistant Staphylococcus aureus (MRSA) under red-light illumination. However, different dose responses were observed for MSSA and MRSA. Whilst the MSSA growth was inhibited to the detection limit of the method with E-141ii at 2.5 µM, >10 µM concentrations were required to inhibit the growth of MRSA. The data also suggest that E-141ii can produce reactive oxygen species (ROS) via Type I reaction by electron transfer from its first excited singlet state to oxygen molecules. Our findings demonstrate that the tested food colorant has great potential to be used in aPDI of MRSA.


Asunto(s)
Colorantes de Alimentos/farmacología , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Viabilidad Microbiana/efectos de los fármacos , Fotoquimioterapia , Colorantes de Alimentos/química , Staphylococcus aureus Resistente a Meticilina/crecimiento & desarrollo , Pruebas de Sensibilidad Microbiana , Especies Reactivas de Oxígeno/metabolismo , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta
2.
Hepatology ; 59(3): 1043-51, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23907731

RESUMEN

UNLABELLED: Heart failure (HF) is, after cirrhosis, the second-most common cause of ascites. Serum B-type natriuretic peptide (BNP) plays an important role in the diagnosis of HF. Therefore, we hypothesized that BNP would be useful in the differential diagnosis of ascites. Consecutive patients with new onset ascites were prospectively enrolled in this cross-sectional study. All patients had measurements of serum-ascites albumin gradient (SAAG), total protein concentration in ascitic fluid, serum, and ascites BNP. We enrolled 218 consecutive patients with ascites resulting from HF (n = 44), cirrhosis (n = 162), peritoneal disease (n = 10), and constrictive pericarditis (n = 2). Compared to SAAG and/or total protein concentration in ascites, the test that best discriminated HF-related ascites from other causes of ascites was serum BNP. A cutoff of >364 pg/mL (sensitivity 98%, specificity 99%, and diagnostic accuracy 99%) had the highest positive likelihood ratio (168.1); that is, it was the best to rule in HF-related ascites. Conversely, a cutoff ≤ 182 pg/mL had the lowest negative likelihood ratio (0.0) and was the best to rule out HF-related ascites. These findings were confirmed in a 60-patient validation cohort. CONCLUSIONS: Serum BNP is more accurate than ascites analyses in the diagnosis of HF-related ascites. The workup of patients with new onset ascites could be streamlined by obtaining serum BNP as an initial test and could forego the need for diagnostic paracentesis, particularly in cases where the cause of ascites is uncertain and/or could be the result of HF.


Asunto(s)
Ascitis , Insuficiencia Cardíaca , Péptido Natriurético Encefálico/sangre , Adulto , Anciano , Ascitis/diagnóstico , Ascitis/etiología , Ascitis/metabolismo , Estudios Transversales , Diagnóstico Diferencial , Femenino , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/metabolismo , Humanos , Cirrosis Hepática/complicaciones , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/metabolismo , Masculino , Persona de Mediana Edad , Enfermedades Peritoneales/complicaciones , Enfermedades Peritoneales/diagnóstico , Enfermedades Peritoneales/metabolismo , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
3.
Cureus ; 15(1): e33727, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36788827

RESUMEN

Charcot-Marie-Tooth (CMT) is a hereditary motor and sensory neuropathy. The disease consists of a spectrum of inherited disorders caused by pathogenic variants in genes, which lead to multiple different clinical phenotypes. It is one of the most common inherited neuromuscular disorders. This disease most commonly presents with symptoms of distal weakness and muscular atrophy, which then lead to foot drop and pés cavus. In this article, we describe the case of a patient who developed muscle atrophy and distal weakness over the course of his 52 years of life, leading to gait impairment and foot deformities. Subsequent investigation led to the acknowledgment of chronic axonal sensorimotor polyneuropathy and genetic identification of the disease's genotype, CMT type 1. .

4.
Cureus ; 14(5): e25213, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35747008

RESUMEN

Endocarditis is an inflammation of the endocardium and is characterized by the presence of vegetation, which may occur in the context of infectious or non-infectious diseases. Despite the higher rate of infective endocarditis diagnosis, it may also surge in other non-infectious conditions such as cancer or chronic inflammatory syndromes. Cancer defines a hypercoagulable state, and cancer-associated thrombophilia can have a diverse clinical presentation, most commonly venous thromboembolism and rarely non-bacterial thrombotic endocarditis (NBTE). The diagnosis of NBTE is difficult and requires a high level of suspicion. The treatment relies on anticoagulant therapy, control of underlying disease, and valve replacement when applied. Independently of the etiology, without treatment, endocarditis may lead to valve dysfunction and to the worst prognosis. In this paper, we describe a case of a patient with persistent fever and NBTE of the tricuspid valve, disclosing a rare presentation of gastric cancer.

5.
J Am Soc Echocardiogr ; 35(12): 1226-1237.e7, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35863542

RESUMEN

BACKGROUND: Transthoracic echocardiography is the leading cardiac imaging modality for patients admitted with COVID-19, a condition of high short-term mortality. The aim of this study was to test the hypothesis that artificial intelligence (AI)-based analysis of echocardiographic images could predict mortality more accurately than conventional analysis by a human expert. METHODS: Patients admitted to 13 hospitals for acute COVID-19 who underwent transthoracic echocardiography were included. Left ventricular ejection fraction (LVEF) and left ventricular longitudinal strain (LVLS) were obtained manually by multiple expert readers and by automated AI software. The ability of the manual and AI analyses to predict all-cause mortality was compared. RESULTS: In total, 870 patients were enrolled. The mortality rate was 27.4% after a mean follow-up period of 230 ± 115 days. AI analysis had lower variability than manual analysis for both LVEF (P = .003) and LVLS (P = .005). AI-derived LVEF and LVLS were predictors of mortality in univariable and multivariable regression analysis (odds ratio, 0.974 [95% CI, 0.956-0.991; P = .003] for LVEF; odds ratio, 1.060 [95% CI, 1.019-1.105; P = .004] for LVLS), but LVEF and LVLS obtained by manual analysis were not. Direct comparison of the predictive value of AI versus manual measurements of LVEF and LVLS showed that AI was significantly better (P = .005 and P = .003, respectively). In addition, AI-derived LVEF and LVLS had more significant and stronger correlations to other objective biomarkers of acute disease than manual reads. CONCLUSIONS: AI-based analysis of LVEF and LVLS had similar feasibility as manual analysis, minimized variability, and consequently increased the statistical power to predict mortality. AI-based, but not manual, analyses were a significant predictor of in-hospital and follow-up mortality.


Asunto(s)
COVID-19 , Función Ventricular Izquierda , Humanos , Volumen Sistólico , Inteligencia Artificial , COVID-19/diagnóstico , Ecocardiografía/métodos
6.
Food Res Int ; 157: 111399, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35761653

RESUMEN

Helichrysum italicum (H. italicum) is a halophyte shrub with bright yellow flowers with a strong curry-like aroma. The essential oils of H. italicum have been used in the production of cosmetics and pharmaceuticals, due to their antiallergic and anti-inflammatory properties. In the agri-food sector, H. italicum flowers can be used for seasoning and flavoring food, and as natural food preservatives. Here, we report on the composition, bioactive compounds, and nutritive value of H. italicum flowers. Flowers were mainly composed of carbohydrates (>80 % dry weight), followed by minerals (6.31 ± 0.95 % dw), protein (5.44 ± 0.35 % dw), and lipids (3.59 % ± 0.53 % dw). High percentages of Fe, Zn, Ca, and K were found in the flower material, along with a high content in antioxidants, polyphenols, and carotenoids, as corroborated by the nuclear magnetic resonance (NMR) data. Flowers were mainly composed of saturated fatty acids (SFAs) (54.50 ± 0.95 % of total FA), followed by polyunsaturated fatty acids (PUFAs) (37.73 ± 1.25 % of total FA) and monounsaturated fatty acids (MUFAs) (7.77 ± 0.34 %), as detected by gas chromatography mass spectrometry (GC-MS). The omega-6 PUFA linoleic acid (22.55 ± 0.76 % of total FA) was the most abundant fatty acid found. Flower extracts showed antimicrobial activity against Saccharomyces cerevisiae and Komagataella phaffii, as well as against Gram-negative (Klebsiella pneumoniae) and Gram-positive (Staphylococcus aureus) bacteria. H. italicum flower material was nontoxic to human intestinal Caco-2 model cells at concentrations up to 1.0 % w/v.


Asunto(s)
Helichrysum , Aceites Volátiles , Células CACO-2 , Flores/química , Helichrysum/química , Humanos , Valor Nutritivo , Aceites Volátiles/química
7.
J Am Soc Echocardiogr ; 35(3): 295-304, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34752928

RESUMEN

BACKGROUND: COVID-19 infection is known to cause a wide array of clinical chronic sequelae, but little is known regarding the long-term cardiac complications. We aim to report echocardiographic follow-up findings and describe the changes in left (LV) and right ventricular (RV) function that occur following acute infection. METHODS: Patients enrolled in the World Alliance Societies of Echocardiography-COVID study with acute COVID-19 infection were asked to return for a follow-up transthoracic echocardiogram. Overall, 198 returned at a mean of 129 days of follow-up, of which 153 had paired baseline and follow-up images that were analyzable, including LV volumes, ejection fraction (LVEF), and longitudinal strain (LVLS). Right-sided echocardiographic parameters included RV global longitudinal strain, RV free wall strain, and RV basal diameter. Paired echocardiographic parameters at baseline and follow-up were compared for the entire cohort and for subgroups based on the baseline LV and RV function. RESULTS: For the entire cohort, echocardiographic markers of LV and RV function at follow-up were not significantly different from baseline (all P > .05). Patients with hyperdynamic LVEF at baseline (>70%), had a significant reduction of LVEF at follow-up (74.3% ± 3.1% vs 64.4% ± 8.1%, P < .001), while patients with reduced LVEF at baseline (<50%) had a significant increase (42.5% ± 5.9% vs 49.3% ± 13.4%, P = .02), and those with normal LVEF had no change. Patients with normal LVLS (<-18%) at baseline had a significant reduction of LVLS at follow-up (-21.6% ± 2.6% vs -20.3% ± 4.0%, P = .006), while patients with impaired LVLS at baseline had a significant improvement at follow-up (-14.5% ± 2.9% vs -16.7% ± 5.2%, P < .001). Patients with abnormal RV global longitudinal strain (>-20%) at baseline had significant improvement at follow-up (-15.2% ± 3.4% vs -17.4% ± 4.9%, P = .004). Patients with abnormal RV basal diameter (>4.5 cm) at baseline had significant improvement at follow-up (4.9 ± 0.7 cm vs 4.6 ± 0.6 cm, P = .019). CONCLUSIONS: Overall, there were no significant changes over time in the LV and RV function of patients recovering from COVID-19 infection. However, differences were observed according to baseline LV and RV function, which may reflect recovery from the acute myocardial injury occurring in the acutely ill. Left ventricular and RV function tends to improve in those with impaired baseline function, while it tends to decrease in those with hyperdynamic LV or normal RV function.


Asunto(s)
COVID-19 , COVID-19/complicaciones , Ecocardiografía/métodos , Estudios de Seguimiento , Ventrículos Cardíacos/diagnóstico por imagen , Humanos , SARS-CoV-2 , Volumen Sistólico , Función Ventricular Izquierda , Función Ventricular Derecha
8.
Protoplasma ; 258(5): 963-977, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33651219

RESUMEN

Phytomelanin is a brown to black pigment found in plant tissues, mainly in Asparagales and Asteraceae species. However, few studies deal with the processes of its synthesis, and there are still many questions to be answered regarding the organelles involved in this process and their functions, especially in vegetative organs. In a previous study with stems and leaves of 77 Vernonieae (Asteraceae) species, phytomelanin was demonstrated to always be associated with sclereids, which suggests the involvement of these cells in the pigment synthesis. Thus, we selected another species of tribe Vernonieae, Piptocarpha axillaris (Less.) Baker, which produces abundant phytomelanin secretion in stem tissues, to investigate which cells and organelles are involved in the synthesis and release of this pigment, as well as its distribution in the tissues. To achieve this goal, stems in different developmental phases were analyzed under light and transmission electron microscopy. Anatomical analysis showed that the polymerization of phytomelanin in P. axillaris starts at the second stem node, in the pith region, and occurs simultaneously with sclereid differentiation. The plastids of cells that will differentiate into sclereids actively participate in the phenolic material synthesis, following the "tannosome" and the "pearl necklace" models, giving rise to the main precursor of phytomelanin, which is then polymerized in the intercellular spaces during the sclerification process of sclereids. In stems with an established secondary structure, the pigment can be observed more frequently in the cortex, pericycle, primary phloem, secondary phloem, and pith.


Asunto(s)
Asteraceae , Floema , Hojas de la Planta , Tallos de la Planta , Plantas , Plastidios
9.
J Am Soc Echocardiogr ; 34(8): 819-830, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34023454

RESUMEN

BACKGROUND: The novel severe acute respiratory syndrome coronavirus-2 virus, which has led to the global coronavirus disease-2019 (COVID-19) pandemic is known to adversely affect the cardiovascular system through multiple mechanisms. In this international, multicenter study conducted by the World Alliance Societies of Echocardiography, we aim to determine the clinical and echocardiographic phenotype of acute cardiac disease in COVID-19 patients, to explore phenotypic differences in different geographic regions across the world, and to identify parameters associated with in-hospital mortality. METHODS: We studied 870 patients with acute COVID-19 infection from 13 medical centers in four world regions (Asia, Europe, United States, Latin America) who had undergone transthoracic echocardiograms. Clinical and laboratory data were collected, including patient outcomes. Anonymized echocardiograms were analyzed with automated, machine learning-derived algorithms to calculate left ventricular (LV) volumes, ejection fraction, and LV longitudinal strain (LS). Right-sided echocardiographic parameters that were measured included right ventricular (RV) LS, RV free-wall strain (FWS), and RV basal diameter. Multivariate regression analysis was performed to identify clinical and echocardiographic parameters associated with in-hospital mortality. RESULTS: Significant regional differences were noted in terms of patient comorbidities, severity of illness, clinical biomarkers, and LV and RV echocardiographic metrics. Overall in-hospital mortality was 21.6%. Parameters associated with mortality in a multivariate analysis were age (odds ratio [OR] = 1.12 [1.05, 1.22], P = .003), previous lung disease (OR = 7.32 [1.56, 42.2], P = .015), LVLS (OR = 1.18 [1.05, 1.36], P = .012), lactic dehydrogenase (OR = 6.17 [1.74, 28.7], P = .009), and RVFWS (OR = 1.14 [1.04, 1.26], P = .007). CONCLUSIONS: Left ventricular dysfunction is noted in approximately 20% and RV dysfunction in approximately 30% of patients with acute COVID-19 illness and portend a poor prognosis. Age at presentation, previous lung disease, lactic dehydrogenase, LVLS, and RVFWS were independently associated with in-hospital mortality. Regional differences in cardiac phenotype highlight the significant differences in patient acuity as well as echocardiographic utilization in different parts of the world.


Asunto(s)
COVID-19/epidemiología , Ecocardiografía/métodos , Cardiopatías/diagnóstico , Cardiopatías/mortalidad , Ventrículos Cardíacos/diagnóstico por imagen , Pandemias , Anciano , COVID-19/diagnóstico , Comorbilidad , Europa (Continente)/epidemiología , Femenino , Estudios de Seguimiento , Mortalidad Hospitalaria/tendencias , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Tasa de Supervivencia/tendencias
10.
ACS Appl Mater Interfaces ; 12(12): 13914-13922, 2020 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-32109040

RESUMEN

In this study, we synthesize glass-ceramics of the new Na1+xGe2(SiO4)x(PO4)3-x NASICON (Na super-ionic conductor) series to evaluate the effect of Si4+/P5+ substitution on the structural, microstructural, and electrical properties of the NaGe2(PO4)3 system. From X-ray diffraction, the presence of the NASICON phase is confirmed in all glass-ceramics. An expansion of the unit cell volume suggesting an increase in the bottleneck of the NASICON structure is also observed. Impedance spectroscopy allowed the separation of grain and grain boundary contributions. We observe that the grain conductivity is higher than the specific grain boundary conductivity in all of the investigated compositions (0 ≤ x ≤ 0.8). The Si4+/P5+ substitution causes an enhancement of about 2 and 3 orders of magnitude in the grain and specific grain boundary conductivities, respectively. This behavior is attributable to the introduction of new charge carriers (Na+) in the NASICON structure and a decrease in the activation energy. Finally, the lowest activation energy for grain (0.586 eV) is observed in the x = 0.6 sample, which indicates the easiest displacement of ions in the investigated series, suggesting that this composition presents the most suitable bottleneck size for (Na+) sodium ion conduction.

11.
PLoS One ; 15(5): e0232467, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32357194

RESUMEN

Basidiomata of Phallales have a diversified morphology with adhesive gleba that exudes an odor, usually unpleasant that attracts mainly insects, which disperse the basidiospores. The genus Blumenavia belongs to the family Clathraceae and, based on morphological features, only two species are currently recognized: B. rhacodes and B. angolensis. However, the morphological characters adopted in species delimitations within this genus are inconsistent, and molecular data are scarce. The present study aimed to review and identify informative characters that contribute to the delimitation of Blumenavia species. Exsiccates from America and Africa were analyzed morphologically, and molecularly, using ITS, LSU, ATP6, RPB2 and TEF-1α markers for Maximum Parsimony, Bayesian and Maximum likelihood analyses, and also for coalescent based species delimitations (BP&P), as well as for bPTP, PhyloMap, Topo-phylogenetic and Geophylogenetic reconstructions. According to our studies, seven species can be considered in the genus: B. rhacodes and B. angolensis are maintained, B. usambarensis and B. toribiotalpaensis are reassessed, and three new species are proposed, B. baturitensis Melanda, M.P. Martín & Baseia, sp. nov., B. crucis-hellenicae G. Coelho, Sulzbacher, Grebenc & Cortez, sp. nov., and B. heroica Melanda, Baseia & M.P. Martín, sp. nov. Blumenavia rhacodes is typified by selecting a lectotype and an epitype. Macromorphological characters considered informative to segregate and delimit the species through integrative taxonomy include length of the basidiomata, color, width and presence of grooves on each arm as well as the glebifer position and shape. These must be clearly observed while the basidiomata are still fresh. Since most materials are usually analyzed after dehydration and deposit in collections, field techniques and protocols to describe fugacious characters from fresh specimen are demanded, as well as the use of molecular analysis, in order to better assess recognition and delimitation of species in Blumenavia.


Asunto(s)
Basidiomycota/clasificación , Basidiomycota/citología , Basidiomycota/genética , Teorema de Bayes , Brasil , ADN de Hongos/genética , México , Filogenia , Especificidad de la Especie , Esporas Fúngicas/citología , Tanzanía
12.
J Prosthodont Res ; 64(3): 301-306, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31718959

RESUMEN

PURPOSE: To compare the effect of different surface treatments (pre-treatments and bonding agents) on the bond strength between glass-fiber post and composite resin, and the topographic alterations of the treated post surface. METHODS: Thirty-six glass-fiber blocks (12mm×10mm×8mm) were specifically manufactured for this study and randomly assigned into 12 groups considering two factors: 'pre-treatments' (-cleaning with 70% alcohol; air-abrasion with silica-coated aluminum oxide particles; 35% hydrogen peroxide) and type of 'bonding agent' (no bonding agent; application of Monobond Plus; RelyX Ceramic Primer; Single Bond Universal). After that, 6 cylindrical templates (1mm high×1mm Ø) were fixed on each block, filled with composite resin (n=18) and light-cured. Specimens were stored under 37°C for 24h and microshear tests (wire loop Ø=0.2mm) were performed. Topographic, roughness and failure analyses were also performed. RESULTS: Different surface pre-treatments led to different topographic and roughness alterations; a higher surface alteration was noted after silica particles air-abrasion, while a slight surface alteration in the hydrogen peroxide group and a smooth pattern were observed in the cleaning group. The factors 'pre-treatments' (p<0.05), 'bonding agent' (p<0.05) and their interaction (p<0.05) influenced the bond strength. Silica coating, apart from bonding agent application, or Single Bond Universal application without pre-treatment promoted the highest bond values. The main failure type was adhesive at the resin-post interface. CONCLUSIONS: In terms of pre-treatments, silica coating promotes the best bonding performance, but pre-treatments can be dispensable when applying Single Bond Universal.


Asunto(s)
Recubrimiento Dental Adhesivo , Cementos de Resina , Óxido de Aluminio , Resinas Compuestas , Análisis del Estrés Dental , Ensayo de Materiales , Silanos , Propiedades de Superficie
13.
Sleep ; 32(5): 637-47, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19480231

RESUMEN

STUDY OBJECTIVES: To test the effects of exercise training on sleep and neurovascular control in patients with systolic heart failure with and without sleep disordered breathing. DESIGN: Prospective interventional study. SETTING: Cardiac rehabilitation and exercise physiology unit and sleep laboratory. PATIENTS: Twenty-five patients with heart failure, aged 42 to 70 years, and New York Heart Association Functional Class I-III were divided into 1 of 3 groups: obstructive sleep apnea (n=8), central sleep apnea (n=9) and no sleep apnea (n=7). INTERVENTIONS Four months of no-training (control) followed by 4 months of an exercise training program (three 60-minute, supervised, exercise sessions per week). MEASURES AND RESULTS: Sleep (polysomnography), microneurography, forearm blood flow (plethysmography), peak VO2, and quality of life were evaluated at baseline and at the end of the control and trained periods. No significant changes occurred in the control period. Exercise training reduced muscle sympathetic nerve activity (P < 0.001) and increased forearm blood flow (P < 0.01), peak VO2( P < 0.01), and quality of life (P < 0.01) in all groups, independent of the presence of sleep apnea. Exercise training improved the apnea-hypopnea index, minimum 0O saturation, and amount stage 3-4 sleep (P < 0.05) in patients with obstructive sleep apnea but had no significant effects in patients with central sleep apnea. CONCLUSIONS: The beneficial effects of exercise training on neurovascular function, functional capacity, and quality of life in patients with systolic dysfunction and heart failure occurs independently of sleep disordered breathing. Exercise training lessens the severity of obstructive sleep apnea but does not affect central sleep apnea in patients with heart failure and sleep disordered breathing.


Asunto(s)
Ejercicio Físico , Insuficiencia Cardíaca/rehabilitación , Apnea Central del Sueño/rehabilitación , Apnea Obstructiva del Sueño/rehabilitación , Adulto , Anciano , Velocidad del Flujo Sanguíneo/fisiología , Ejercicio Físico/fisiología , Femenino , Antebrazo/irrigación sanguínea , Insuficiencia Cardíaca/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Músculo Esquelético/inervación , Oxígeno/sangre , Pletismografía , Polisomnografía , Estudios Prospectivos , Calidad de Vida , Apnea Central del Sueño/fisiopatología , Apnea Obstructiva del Sueño/fisiopatología , Sistema Nervioso Simpático/fisiopatología
14.
Echocardiography ; 26(6): 675-83, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19392841

RESUMEN

BACKGROUND: There is a paucity of information concerning left ventricular (LV) dyssynchrony assessment by real time three-dimensional (3D) echocardiography (RT3DE) versus tissue Doppler imaging (TDI). AIMS: To compare RT3DE and TDI LV dyssynchrony assessment. METHODS: A prospective study of 92 individuals (56 men, age 47 +/- 10 years), 32 with dilated cardiomyopathy (CMP), and 60 healthy individuals. By RT3DE, we measured the LV% dyssynchrony index (DI) of 6, 12, and 16 segments (SDI). By pulsed-wave TDI, we measured the QS electromechanical interval in the basal segments of the mitral valve annulus of the septum, the lateral, anterior and inferior walls, and the TDI% DI. RESULTS: In the normal group, the 3D DI was 1.1 +/- 0.8%, 1.4 +/- 1.3%, 1.8 +/- 1.7%, for 6 segments, 12 segments, and SDI, respectively. The correlation coefficient (Pearson's r) for the TDI DI and SDI was r = 0.2381 (P = 0.0470). In CMP group, the 3D DI was 4.6 +/- 5.4%, 7.9 +/- 7.1%, 11.1 +/- 7.1%, for 6 segments, 12 segments, and SDI, respectively. The correlation coefficient for TDI DI and SDI was r = 0.7838 (P < 0.0001). CONCLUSIONS: We observed a good correlation between RT3DE and tissue Doppler LV dyssynchrony assessment in patients with advanced heart failure.


Asunto(s)
Ecocardiografía Tridimensional/métodos , Diagnóstico por Imagen de Elasticidad/métodos , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/diagnóstico por imagen , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/etiología , Sistemas de Computación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
16.
Eur J Gastroenterol Hepatol ; 30(8): 930-937, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29979644

RESUMEN

BACKGROUND: Cirrhotic cardiomyopathy is characterized by an attenuated contractile response to stress. Long-term exposure of ß-adrenergic receptors to persistently high levels of catecholamines has been implicated in its pathogenesis. We hypothesized that ß-blockade with metoprolol could reverse the changes in heart function and morphology in cirrhotic cardiomyopathy. PATIENTS AND METHODS: In this prospective randomized trial, we included 78 patients aged between 18 and 60 years with abnormal cardiac output response under dobutamine stress echocardiography, without primary cardiac disease or a history of alcohol intake. Patients were assigned randomly to receive metoprolol or placebo for 6 months. The primary endpoint was the improvement in cardiac output response to stress, measured by an increase in the left ventricle stroke volume more than 30%. RESULTS: Three (7.3%) patients in the metoprolol group and nine (24.3%) patients in the placebo group showed improved stroke volume (P=0.057). Diastolic dysfunction was found in two (4.8%) patients before and in five (15.6%) patients after therapy in the metoprolol group, and in 10 (27%) patients before and nine (31%) patients after therapy in the placebo group (P=0.67). After treatment, no echocardiography parameter of morphology was significantly different between metoprolol or placebo groups. No significant differences were observed in noradrenaline, plasma renin activity, and troponin levels between groups. Cirrhosis-related clinical events, including hospitalizations and mortality, were not significantly different between the two groups. Six months of therapy with ß-blocker did not ameliorate heart function and morphology in patients with cirrhotic cardiomyopathy.


Asunto(s)
Antagonistas de Receptores Adrenérgicos beta 1/uso terapéutico , Cardiomiopatías/tratamiento farmacológico , Cirrosis Hepática/tratamiento farmacológico , Metoprolol/uso terapéutico , Adolescente , Antagonistas de Receptores Adrenérgicos beta 1/efectos adversos , Adulto , Biomarcadores/sangre , Brasil , Gasto Cardíaco/efectos de los fármacos , Cardiomiopatías/diagnóstico por imagen , Cardiomiopatías/etiología , Cardiomiopatías/fisiopatología , Ecocardiografía de Estrés , Femenino , Humanos , Cirrosis Hepática/complicaciones , Cirrosis Hepática/diagnóstico , Masculino , Metoprolol/efectos adversos , Persona de Mediana Edad , Contracción Miocárdica/efectos de los fármacos , Norepinefrina/sangre , Estudios Prospectivos , Recuperación de la Función , Renina/sangre , Factores de Tiempo , Resultado del Tratamiento , Troponina/sangre , Función Ventricular Izquierda/efectos de los fármacos , Remodelación Ventricular/efectos de los fármacos , Adulto Joven
17.
Protoplasma ; 252(1): 3-20, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24893589

RESUMEN

Seagrasses, which form an integral part of the worldwide coastal habitat, are considered highly relevant from an ecological point of view. Due to the scarcity of anatomical information, the present study analyzed the morphoanatomy, histochemistry, and ultrastructure of Halophila decipiens, Halodule wrightii, and Ruppia maritima leaves, discussing their adaptations to the marine environments observed throughout the southwestern tropical and subtropical Atlantic coast. The leaves of these three species feature a uniseriate epidermis with the presence of chloroplasts in large quantities and absence of stomata. The vascular system consists of a central vascular bundle with sieve tube elements of the phloem and protoxylem lacunae, as well as small vascular bundles near the leaf margins. The leaves of H. decipiens possess trichomes, but no mesophyll in the leaf margins. The mesophyll of H. wrightii and R. maritima is homogeneous with chlorenchyma cells and air lacunae scattered throughout the leaf. The histochemistry analysis revealed the absence of amyloplasts and the presence of proteins in the outer periclinal walls of ordinary epidermal cells of the three species. It was also possible to detect the presence of idioblasts containing phenolic compounds in H. decipiens and R. maritima. The ultrastructural analysis of the three species revealed many elliptical chloroplasts, with organized thylakoids, expansion of the epidermal cell wall into the cytoplasm, and a thin cuticle. Hydropoten were also observed in the three specimens. The results show that the species analyzed have important adaptations which enable their survival in the marine environment.


Asunto(s)
Hojas de la Planta/ultraestructura , Poaceae/ultraestructura , Aclimatación , Océano Atlántico , Monitoreo del Ambiente
18.
J Phys Chem B ; 118(51): 14942-8, 2014 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-25496494

RESUMEN

Transition metal containing glasses have unique electrical properties and are therefore often used for electrochemical applications, such as in batteries. Among oxide glasses, vanadium tellurite glasses exhibit the highest electronic conductivity and thus the high potential for applications. In this work, we investigate how the dynamic and physical properties vary with composition in the vanadium tellurite system. The results show that there exists a critical V(2)O(5) concentration of 45 mol %, above which the local structure is subjected to a drastic change with increasing V(2)O(5), leading to abrupt changes in both hardness and liquid fragility. Electronic conductivity does not follow the expected correlation to the valence state of the vanadium as predicted by the Mott-Austin equation but shows a linear correlation to the mean distance between vanadium ions. These findings could contribute to designing optimum vanadium tellurite compositions for electrochemical devices. The work gives insight into the mechanism of electron conduction in the vanadium tellurite systems.

19.
Protoplasma ; 250(6): 1303-13, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23708376

RESUMEN

Ultraviolet-B radiation (UVBR) affects plants in many important ways, including reduction of growth rate and primary productivity, and changes in ultrastructures. Rice (Oryza sativa) is one of the most cultivated cereals in the world, along with corn and wheat, representing over 50% of agricultural production. In this study, we examined O. sativa plants exposed to ambient outdoor radiation and laboratory-controlled photosynthetically active radiation (PAR) and PAR + UVBR conditions for 2 h/day during 30 days of cultivation. The samples were studied for morphological and ultrastructural characteristics, and physiological parameters. PAR + UVBR caused changes in the ultrastructure of leaf of O. sativa and leaf morphology (leaf index, leaf area and specific leaf area, trichomes, and papillae), plant biomass (dry and fresh weight), photosynthetic pigments, phenolic compounds, and protein content. As a photoprotective acclimation strategy against PAR + UVBR damage, an increase of 66.24% in phenolic compounds was observed. Furthermore, PAR + UVBR treatment altering the levels of chlorophylls a and b, and total chlorophyll. In addition, total carotenoid contents decreased after PAR + UVBR treatment. The results strongly suggested that PAR + UVBR negatively affects the ultrastructure, morphology, photosynthetic pigments, and growth rates of leaf of O. sativa and, in the long term, it could affect the viability of this economically important plant.


Asunto(s)
Oryza/fisiología , Oryza/ultraestructura , Rayos Ultravioleta , Oryza/efectos de la radiación , Fotosíntesis/efectos de la radiación , Pigmentos Biológicos/metabolismo , Epidermis de la Planta/citología , Epidermis de la Planta/efectos de la radiación , Epidermis de la Planta/ultraestructura , Hojas de la Planta/anatomía & histología , Hojas de la Planta/efectos de la radiación , Proteínas de Plantas/metabolismo , Polifenoles/metabolismo , Solubilidad
20.
Am J Vet Res ; 72(10): 1361-8, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21962279

RESUMEN

OBJECTIVE: To evaluate enterotoxin production, enterotoxin gene distribution, and genetic diversity of Staphylococcus aureus in milk obtained from cows with subclinical mastitis. SAMPLE: Milk samples obtained from 350 cows (1,354 mammary glands) on 11 Wisconsin dairy farms. PROCEDURES: Of 252 S aureus isolates obtained from 146 cows, 83 isolates (from 66 cows with subclinical mastitis) were compared genotypically by use of pulsed-field gel electrophoresis and via PCR identification of toxic shock syndrome toxin 1 (TSST-1) and classical S aureus enterotoxin genes (sea, seb, sec, sed, and see). RESULTS: Among the 83 S aureus isolates, ≥ 1 enterotoxin genes were identified in 8 (9.6%). Enterotoxin gene distribution was as follows: TSST-1, 7 isolates (8.4%); sec, 5 isolates (6.0%); and sed, 2 isolates (2.4%). Enterotoxin genes sea, seb, and see were not identified. Twelve pulsotypes and 5 subtypes were identified among the 83 isolates; 5 of the 12 pulsotypes were represented by only 1 isolate. In cows of 1 herd, only a single S aureus pulsotype was detected; in cows on most other farms, a variety of pulsotypes were identified. One pulsotype was recovered from 4 farms (n = 23 cows) and another from 5 other farms (16). Isolates with an enterotoxin gene were represented by 6 pulsotypes. CONCLUSIONS AND CLINICAL RELEVANCE: S aureus classical enterotoxins and TSST-1 were rarely recovered from milk samples obtained from cows with subclinical mastitis in Wisconsin. Diverse pulsotypes of S aureus were detected within and among farms, indicating that different strains of S aureus cause subclinical mastitis in dairy cows.


Asunto(s)
Toxinas Bacterianas/genética , Enfermedades de los Bovinos/microbiología , Enterotoxinas/genética , Variación Genética , Mastitis/veterinaria , Leche/microbiología , Staphylococcus aureus/genética , Superantígenos/genética , Animales , Bovinos , Electroforesis en Gel de Campo Pulsado/veterinaria , Femenino , Mastitis/microbiología , Reacción en Cadena de la Polimerasa/veterinaria , Especificidad de la Especie , Staphylococcus aureus/metabolismo , Wisconsin
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA