Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 45
Filtrar
Más filtros












Base de datos
Intervalo de año de publicación
1.
Br J Pharmacol ; 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38773354

RESUMEN

BACKGROUND AND PURPOSE: The ryanodine receptor 2 (RyR2) is present in both the heart and kidneys, and plays a crucial role in maintaining intracellular Ca2+ homeostasis in cells in these organs. This study aimed to investigate the impact of M201-A on RyR2, as well as studying its effects on cardiac and renal functions in preclinical and clinical studies. EXPERIMENTAL APPROACH: Following the administration of M201-A (1,4-benzothiazepine-1-oxide derivative), we monitored diastolic Ca2+ leak via RyR2 and intracellular Ca2+ concentration in isolated rat cardiomyocytes and in cardiac and renal function in animals. In a clinical study, M201-A was administered intravenously at doses of 0.2 and 0.4 mg·kg-1 once daily for 20 min for four consecutive days in healthy males, with the assessment of haemodynamic responses. KEY RESULTS: In rat heart cells, M201-A effectively inhibited spontaneous diastolic Ca2+ leakage through RyR2 and exhibited positive lusi-inotropic effects on the rat heart. Additionally, it enhanced natriuresis and improved renal function in dogs. In human clinical studies, when administered intravenously, M201-A demonstrated an increase in natriuresis, glomerular filtration rate and creatinine clearance, while maintaining acceptable levels of drug safety and tolerability. CONCLUSIONS AND IMPLICATIONS: The novel drug M201-A inhibited diastolic Ca2+ leak via RyR2, improved cardiac lusi-inotropic effects in rats, and enhanced natriuresis and renal function in humans. These findings suggest that this drug may offer a potential new treatment option for chronic kidney disease and heart failure.

2.
Cardiovasc Res ; 119(16): 2663-2671, 2023 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-37433039

RESUMEN

AIMS: Myocardial infarction (MI) is a major cause of death worldwide. Effective treatments are required to improve recovery of cardiac function following MI, with the aim of improving patient outcomes and preventing progression to heart failure. The perfused but hypocontractile region bordering an infarct is functionally distinct from the remote surviving myocardium and is a determinant of adverse remodelling and cardiac contractility. Expression of the transcription factor RUNX1 is increased in the border zone 1-day after MI, suggesting potential for targeted therapeutic intervention. OBJECTIVE: This study sought to investigate whether an increase in RUNX1 in the border zone can be therapeutically targeted to preserve contractility following MI. METHODS AND RESULTS: In this work we demonstrate that Runx1 drives reductions in cardiomyocyte contractility, calcium handling, mitochondrial density, and expression of genes important for oxidative phosphorylation. Both tamoxifen-inducible Runx1-deficient and essential co-factor common ß subunit (Cbfß)-deficient cardiomyocyte-specific mouse models demonstrated that antagonizing RUNX1 function preserves the expression of genes important for oxidative phosphorylation following MI. Antagonizing RUNX1 expression via short-hairpin RNA interference preserved contractile function following MI. Equivalent effects were obtained with a small molecule inhibitor (Ro5-3335) that reduces RUNX1 function by blocking its interaction with CBFß. CONCLUSIONS: Our results confirm the translational potential of RUNX1 as a novel therapeutic target in MI, with wider opportunities for use across a range of cardiac diseases where RUNX1 drives adverse cardiac remodelling.


Asunto(s)
Insuficiencia Cardíaca , Infarto del Miocardio , Animales , Ratones , Subunidad alfa 2 del Factor de Unión al Sitio Principal/genética , Subunidad alfa 2 del Factor de Unión al Sitio Principal/metabolismo , Insuficiencia Cardíaca/metabolismo , Infarto del Miocardio/genética , Infarto del Miocardio/prevención & control , Infarto del Miocardio/tratamiento farmacológico , Miocardio/metabolismo , Miocitos Cardíacos/metabolismo , Remodelación Ventricular
3.
Phytother Res ; 37(5): 2119-2143, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37014255

RESUMEN

Rosmarinic acid (RA) is a natural phenolic compound present in culinary herbs of the Boraginaceae, Lamiaceae/Labiatae, and Nepetoideae families. While the medicinal applications of these plants have been known for ages, RA has only been relatively recently established as an effective ameliorative agent against various disorders including cardiac diseases, cancer, and neuropathologies. In particular, several studies have confirmed the neuroprotective potential of RA in multiple cellular and animal models, as well as in clinical studies. The neuroprotective effects mediated by RA stem from its multimodal actions on a plethora of cellular and molecular pathways; including oxidative, bioenergetic, neuroinflammatory, and synaptic signaling. In recent years, RA has garnered tremendous interest as an ideal therapeutic candidate for treating neurodegenerative diseases. This review first briefly discusses the pharmacokinetics of RA and then proceeds to detail the neuroprotective mechanisms of RA at the molecular levels. Finally, the authors focus on the ameliorative potential of RA against several central nervous system (CNS) disorders, ranging from neuropsychological stress and epilepsy to neurodegenerative diseases such as Alzheimer's disease, Huntington's disease, Parkinson's disease, Lewy body dementia, and amyotrophic lateral sclerosis.


Asunto(s)
Enfermedad de Alzheimer , Enfermedades Neurodegenerativas , Fármacos Neuroprotectores , Animales , Enfermedades Neurodegenerativas/tratamiento farmacológico , Enfermedad de Alzheimer/tratamiento farmacológico , Neuroprotección , Cinamatos/farmacología , Cinamatos/uso terapéutico , Cinamatos/metabolismo , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Ácido Rosmarínico
4.
Pflugers Arch ; 474(12): 1311-1321, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36131146

RESUMEN

Atrial fibrillation (AF) from elevated adrenergic activity may involve increased atrial L-type Ca2+ current (ICaL) by noradrenaline (NA). However, the contribution of the adrenoceptor (AR) sub-types to such ICaL-increase is poorly understood, particularly in human. We therefore investigated effects of various broad-action and sub-type-specific α- and ß-AR antagonists on NA-stimulated atrial ICaL. ICaL was recorded by whole-cell-patch clamp at 37 °C in myocytes isolated enzymatically from atrial tissues from consenting patients undergoing elective cardiac surgery and from rabbits. NA markedly increased human atrial ICaL, maximally by ~ 2.5-fold, with EC75 310 nM. Propranolol (ß1 + ß2-AR antagonist, 0.2 microM) substantially decreased NA (310 nM)-stimulated ICaL, in human and rabbit. Phentolamine (α1 + α2-AR antagonist, 1 microM) also decreased NA-stimulated ICaL. CGP20712A (ß1-AR antagonist, 0.3 microM) and prazosin (α1-AR antagonist, 0.5 microM) each decreased NA-stimulated ICaL in both species. ICI118551 (ß2-AR antagonist, 0.1 microM), in the presence of NA + CGP20712A, had no significant effect on ICaL in human atrial myocytes, but increased it in rabbit. Yohimbine (α2-AR antagonist, 10 microM), with NA + prazosin, had no significant effect on human or rabbit ICaL. Stimulation of atrial ICaL by NA is mediated, based on AR sub-type antagonist responses, mainly by activating ß1- and α1-ARs in both human and rabbit, with a ß2-inhibitory contribution evident in rabbit, and negligible α2 involvement in either species. This improved understanding of AR sub-type contributions to noradrenergic activation of atrial ICaL could help inform future potential optimisation of pharmacological AR-antagonism strategies for inhibiting adrenergic AF.


Asunto(s)
Canales de Calcio Tipo L , Miocitos Cardíacos , Norepinefrina , Receptores Adrenérgicos alfa , Receptores Adrenérgicos beta , Animales , Humanos , Conejos , Fibrilación Atrial/fisiopatología , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/fisiología , Norepinefrina/farmacología , Norepinefrina/fisiología , Prazosina/farmacología , Receptores Adrenérgicos alfa 2 , Atrios Cardíacos/citología , Receptores Adrenérgicos beta/fisiología , Receptores Adrenérgicos alfa/fisiología , Antagonistas Adrenérgicos alfa/farmacología , Antagonistas Adrenérgicos beta/farmacología , Canales de Calcio Tipo L/fisiología
5.
Environ Sci Pollut Res Int ; 29(12): 17892-17918, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34686959

RESUMEN

In the present study, total suspended particulate matter (TSP) samples were collected at 47 different sites (47 grids of 5 × 5 km2 area) of Delhi during winter (January-February 2019) in campaign mode. To understand the spatial variation of sources, TSP samples were analyzed for chemical compositions including carbonaceous species [organic carbon (OC), elemental carbon (EC), and water-soluble organic carbon (WSOC)], water-soluble total nitrogen (WSTN), water-soluble inorganic nitrogen (WSIN), polycyclic aromatic hydrocarbons (16 PAHs), water-soluble inorganic species (WSIS) (F-, Cl-, SO42-, NO2-, NO3-, PO43-, NH4+, Ca2+, Mg2+, Na+, and K+), and major and minor trace elements (B, Na, Mg, Al, P, S, Cl, K, Ca, Ti, Fe, Zn, Cr, Mn, Cu, As, Pd, F, and Ag). During the campaign, the maximum concentration of several components of TSP (996 µg/m3) was recorded at the Rana Pratap Bagh area, representing a pollution hotspot of Delhi. The maximum concentrations of PAHs were recorded at Udhyog Nagar, a region close to heavily loaded diesel vehicles, small rubber factories, and waste burning areas. Higher content of Cl- and Cl-/Na+ ratio (>1.7) suggests the presence of nonmarine anthropogenic sources of Cl- over Delhi. Minimum concentrations of OC, EC, WSOC, PAHs, and WSIS in TSP were observed at Kalkaji, representing the least polluted area in Delhi. Enrichment factor <5.0 at several locations and a significant correlation of Al with Mg, Fe, Ti, and Ca and C/N ratio indicated the abundance of mineral/crustal dust in TSP over Delhi. Principal component analysis (PCA) was also performed for the source apportionment of TSP, and extracted soil dust was found to be the major contributor to TSP, followed by biomass burning, open waste burning, secondary aerosol, and vehicular emissions.


Asunto(s)
Contaminantes Atmosféricos , Material Particulado , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , India , Tamaño de la Partícula , Material Particulado/análisis , Estaciones del Año , Emisiones de Vehículos/análisis
6.
Biotechnol Lett ; 44(1): 1-22, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34734354

RESUMEN

Reactive oxygen species (ROS) is consistently recognized as a threat to living organisms, especially for human beings. For proper working of cellular signaling, functioning, and survival, a strict and balanced level of ROS is necessary. Superoxide dismutase (SOD); a group of metalloenzymes provides an important antioxidant defense mechanism, required to preserve the level of ROS in the body. The enzyme reveals the therapeutic potential against various diseases due to a deficiency in the ROS level. The review illustrates the numerous clinical aspects of SOD in various physiological and pathological conditions such as cancer, diabetes, arthritis, cardiovascular, neurodegenerative diseases, etc., with the mechanism of action. Despite limitations, the SOD enzyme has proved as a powerful tool against diseases, and various forms of conjugates and mimetics have been developed and reported to make it more efficient. Extensive studies need in this direction for use of natural SOD-based therapeutics for the prevention and cure of diseases.


Asunto(s)
Neoplasias , Enfermedades Neurodegenerativas , Antioxidantes , Humanos , Neoplasias/tratamiento farmacológico , Enfermedades Neurodegenerativas/tratamiento farmacológico , Especies Reactivas de Oxígeno , Superóxido Dismutasa
7.
J Virol Methods ; 301: 114418, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34919979

RESUMEN

The coronavirus pandemic has lasted for more than a year now and still remains the leading cause of concern, worldwide. The causal agent; SARS- CoV-2, leads to the development of respiratory distress in the lower respiratory tract, sometimes leading to fatalities. Keeping in mind the discovery of mutant strains across the world, as well as the delay in vaccinations across vast populations, most people speculate boosting their immune systems as a preventive and precautionary measure. One of the most commonly observed conditions that hamper immunity; Vitamin D deficiency has been linked to the onset and the alteration of course of the disease in patients and is also being explored as a potential drug supplement. These surmises make it essential to study deep into the speculations. This review aims to overview the possible correlations between Vitamin D and COVID-19.


Asunto(s)
COVID-19 , Deficiencia de Vitamina D , Humanos , Pandemias , SARS-CoV-2 , Vitamina D , Deficiencia de Vitamina D/epidemiología
8.
Heart Rhythm ; 18(7): 1212-1220, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33737232

RESUMEN

BACKGROUND: Although atrial fibrillation ablation is increasingly used for rhythm control therapy, antiarrhythmic drugs (AADs) are commonly used, either alone or in combination with ablation. The effectiveness of AADs is highly variable. Previous work from our group suggests that alterations in atrial resting membrane potential (RMP) induced by low Pitx2 expression could explain the variable effect of flecainide. OBJECTIVE: The purpose of this study was to assess whether alterations in atrial/cardiac RMP modify the effectiveness of multiple clinically used AADs. METHODS: The sodium channel blocking effects of propafenone (300 nM, 1 µM), flecainide (1 µM), and dronedarone (5 µM, 10 µM) were measured in human stem cell-derived cardiac myocytes, HEK293 expressing human NaV1.5, primary murine atrial cardiac myocytes, and murine hearts with reduced Pitx2c. RESULTS: A more positive atrial RMP delayed INa recovery, slowed channel inactivation, and decreased peak action potential (AP) upstroke velocity. All 3 AADs displayed enhanced sodium channel block at more positive atrial RMPs. Dronedarone was the most sensitive to changes in atrial RMP. Dronedarone caused greater reductions in AP amplitude and peak AP upstroke velocity at more positive RMPs. Dronedarone evoked greater prolongation of the atrial effective refractory period and postrepolarization refractoriness in murine Langendorff-perfused Pitx2c+/- hearts, which have a more positive RMP compared to wild type. CONCLUSION: Atrial RMP modifies the effectiveness of several clinically used AADs. Dronedarone is more sensitive to changes in atrial RMP than flecainide or propafenone. Identifying and modifying atrial RMP may offer a novel approach to enhancing the effectiveness of AADs or personalizing AAD selection.


Asunto(s)
Fibrilación Atrial/metabolismo , Dronedarona/uso terapéutico , Flecainida/uso terapéutico , Atrios Cardíacos/metabolismo , Potenciales de la Membrana/efectos de los fármacos , Propafenona/uso terapéutico , Sodio/metabolismo , Potenciales de Acción/efectos de los fármacos , Animales , Antiarrítmicos/uso terapéutico , Fibrilación Atrial/tratamiento farmacológico , Fibrilación Atrial/fisiopatología , Modelos Animales de Enfermedad , Femenino , Atrios Cardíacos/fisiopatología , Masculino , Ratones , Bloqueadores del Canal de Sodio Activado por Voltaje/uso terapéutico
9.
Clin Gastroenterol Hepatol ; 18(2): 486-495.e3, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31077821

RESUMEN

BACKGROUND & AIMS: Endogenous heparinoids or heparin-like effects (HLEs) can cause coagulation failure in patients with cirrhosis and sepsis. We performed a prospective study of the association between HLE and bleeding events, sepsis, and outcomes of patients with severe alcohol-associated hepatitis. METHODS: Our final analysis comprised 78 patients with severe alcohol-associated hepatitis (44.3 ± 11.7 years; all male; discriminant function >32) who presented without sepsis at a single center in India from August 2015 through August 2016. Blood samples were collected at days 0, 3, and 7 after presentation and assessed by a global coagulation assay; by SONOCLOT (global and heparinase treated); and in assays for factor VIII, von Willebrand factor, protein C, and antithrombin. Patients were followed for sepsis, bleeding and outcome. The primary outcome was association of HLE with survival 28 days after presentation. RESULTS: HLEs were observed in 32 patients (41%) at day 0, 27 patients (34.6%) at day 3, and 28 patients (35.9%) patients at day 7. Factors associated with mortality at day 0 were factor VIII activity >160% (hazard ratio [HR], 3.1; 95% CI, 1.4-9.5; P = .026), level of protein C <34% (HR, 0.7; 95% CI, 0.5-0.8; P = .037), antithrombin activity <28% (HR, 0.7; 95% CI, 0.3-1.1; P = .008) and international normalized ratio >2.6 (HR, 2.3; 95% CI, 1.8-9.7; P = .010). In multivariate analyses, only factor VIII activity (HR, 2.3; 95% CI, 1.6-7.8; P = .046), international normalized ratio (1.9; 95% CI, 1.2-4.3; P = .039), level of protein C (HR, 0.9; 95% CI, 0.7-1.1; P = .052) and model for end-stage liver disease score (HR, 3.2; 95% CI, 1.9-10.2; P = .042) were associated with mortality. Episodes of epistaxis, hemorrhoid bleeding, hemoperitoneum, and pulmonary hemorrhage occurred in 10.2%, 12.3%, 3.4%, and 4.5% of patients respectively. The presence of HLE at day 0 increased the risk of sepsis (HR, 2.5; 95% CI, 2.2-4.3; P = .002), bleeding (HR, 1.4; 95% CI, 1.2-5.3; P = .004) and death (HR, 1.2; 95% CI, 1.4-1.7; P = .044). CONCLUSIONS: In a prospective study of patients with severe alcohol-associated hepatitis, we associated HLE with coagulation abnormalities, risk of sepsis, and mortality. Clinicaltrials.govNCT02307409.


Asunto(s)
Enfermedad Hepática en Estado Terminal , Hepatitis Alcohólica , Sepsis , Adulto , Hemorragia Gastrointestinal , Heparina/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sepsis/complicaciones , Sepsis/epidemiología , Índice de Severidad de la Enfermedad
10.
J Physiol ; 597(14): 3619-3638, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31093979

RESUMEN

KEY POINTS: Early-afterdepolarizations (EADs) are abnormal action potential oscillations and a known cause of cardiac arrhythmias. Ventricular EADs involve reactivation of a Ca2+ current (ICaL ) in its 'window region' voltage range. However, electrical mechanisms of atrial EADs, a potential cause of atrial fibrillation, are poorly understood. Atrial cells were obtained from consenting patients undergoing heart surgery, as well as from rabbits. ICaL was blocked with nifedipine and then a hybrid patch clamp/mathematical-modelling technique, 'dynamic clamping', was used to record action potentials at the same time as injecting an artificial, modifiable, ICaL (ICaL,D-C ). Progressively widening the ICaL,D-C window region produced EADs of various types, dependent on window width. EAD production was strongest upon moving the activation (vs. inactivation) side of the window. EADs were then induced by a different method: increasing ICaL,D-C amplitude and/or K+ channel-blockade (4-aminopyridine). Narrowing of the ICaL,D-C window by ∼10 mV abolished these EADs. Atrial ICaL window narrowing is worthy of further testing as a potential anti-atrial fibrillation drug mechanism. ABSTRACT: Atrial early-afterdepolarizations (EADs) may contribute to atrial fibrillation (AF), perhaps involving reactivation of L-type Ca2+ current (ICaL ) in its window region voltage range. The present study aimed (i) to validate the dynamic clamp technique for modifying the ICaL contribution to atrial action potential (AP) waveform; (ii) to investigate the effects of widening the window ICaL on EAD-propensity; and (iii) to test whether EADs from increased ICaL and AP duration are supressed by narrowing the window ICaL . ICaL and APs were recorded from rabbit and human atrial myocytes by whole-cell-patch clamp. During AP recording, ICaL was inhibited (3 µm nifedipine) and replaced by a dynamic clamp model current, ICaL,D-C (tuned to native ICaL characteristics), computed in real-time (every 50 µs) based on myocyte membrane potential. ICaL,D-C -injection restored the nifedipine-suppressed AP plateau. Widening the window ICaL,D-C , symmetrically by stepwise simultaneous equal shifts of half-voltages (V0.5 ) of ICaL,D-C activation (negatively) and inactivation (positively), generated EADs (single, multiple or preceding repolarization failure) in a window width-dependent manner, as well as AP alternans. A stronger EAD-generating effect resulted from independently shifting activation V0.5 (asymmetrical widening) than inactivation V0.5 ; for example, a 15 mV activation shift produced EADs in nine of 17 (53%) human atrial myocytes vs. 0 of 18 from inactivation shift (P < 0.05). In 11 rabbit atrial myocytes in which EADs were generated either by increasing the conductance of normal window width ICaL,D-C or subsequent 4-aminopyridine (2 mm), window ICaL,D-C narrowing (10 mV) abolished EADs of all types (P < 0.05). The present study validated the dynamic clamp for ICaL , which is novel in atrial cardiomyocytes, and showed that EADs of various types are generated by widening (particularly asymmetrically) the window ICaL , as well as abolished by narrowing it. Window ICaL narrowing is a potential therapeutic mechanism worth pursuing in the search for improved anti-AF drugs.


Asunto(s)
Potenciales de Acción/fisiología , Calcio/metabolismo , Anciano , Animales , Fibrilación Atrial/metabolismo , Canales de Calcio Tipo L/metabolismo , Células Cultivadas , Femenino , Atrios Cardíacos/metabolismo , Humanos , Masculino , Miocitos Cardíacos/metabolismo , Técnicas de Placa-Clamp/métodos , Conejos
11.
Liver Int ; 39(4): 694-704, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30589495

RESUMEN

BACKGROUND: Patients with acute-on-chronic liver failure (ACLF) have coagulation failure in the setting of systemic inflammatory syndrome (SIRS), sepsis and extra-hepatic organ failures. METHODS: Consecutive ACLF patients without sepsis at baseline were assessed at days 0, 3 and 7 with thromboelastography (TEG) and specific assays (Factor VIII, von Willebrand factor [vWF], protein C and antithrombin III [ATIII]) and followed for development of sepsis, bleeding and outcome. RESULTS: Of 243 patients, 114 (63% ethanol related; mean age 44.3 ± 11.7 years; 90% male) were recruited. SIRS was noted in 39 (34.2%), 45 (39.5%) and 46 (40%) patients at days 0, 3 and 7 and sepsis in 28 (24%) and 52 (56.1%) patients at days 3 and 7 respectively. The 28- and 90-day survivals were 62% and 51% respectively. A hypocoagulable TEG at baseline was a predictor of bleeding (hazard ratio [HR] 2.1; CI 1.6-4.9; P = 0.050) and mortality (HR 1.9; CI 1.3-7.9; P = 0.043). ACLF patients had increased Factor VIII, vWF, tissue factor levels and tissue plasminogen activator (tPA) activity with reduced protein C and ATIII. Coagulation parameters like Coagulation Index (HR 2.1; CI 1.1-4.5; P = 0.044),clot lysis (HR 3.2; CI 1.9-3.4; P = 0.033), low protein C < 30% (HR 2.1; CI 1.5-2.8; P = 0.017), ATIII (HR 1.4; CI 1.7-3.1; P = 0.052) and tPA (HR 1.5; CI 1.1-2.4; P = 0.052) were predictors of mortality at day 28. Protein C activity <30% (HR 1.3; CI 1.0-2.9; P = 0.042) and tPA >20 ng/mL (HR 1.2; CI 1.1-2.1; P = 0.040) predicted mortality when adjusted for age, gender and baseline MELD. CONCLUSIONS: Dynamic coagulation derangements, measured by TEG, determine the likelihood of bleeding and mortality in ACLF.


Asunto(s)
Insuficiencia Hepática Crónica Agudizada/complicaciones , Hemorragia/etiología , Hemorragia/mortalidad , Sepsis/etiología , Síndrome de Respuesta Inflamatoria Sistémica/etiología , Insuficiencia Hepática Crónica Agudizada/fisiopatología , Adulto , Coagulación Sanguínea , Pruebas de Coagulación Sanguínea , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Sepsis/epidemiología , Índice de Severidad de la Enfermedad , Síndrome de Respuesta Inflamatoria Sistémica/epidemiología , Factores de Tiempo
12.
Indian J Pathol Microbiol ; 61(4): 604-606, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30303163

RESUMEN

Synovial hemangioma is a rare, benign, vascular tumor of synovium leading to joint pain and swelling. The most common site is the knee joint, but rare cases involving other sites have also been reported. We report two rare cases of synovial hemangioma, one involving the ankle joint and other involving the wrist joint. Histopathology is the gold standard for diagnosis of these cases. Early treatment is warranted to prevent the risk of permanent joint damage.


Asunto(s)
Articulación del Tobillo , Hemangioma/patología , Membrana Sinovial/fisiología , Articulación de la Muñeca , Adolescente , Femenino , Humanos , Masculino , Persona de Mediana Edad
13.
Front Physiol ; 9: 1211, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30245635

RESUMEN

Introduction: The development of improved diagnosis, management, and treatment strategies for human atrial fibrillation (AF) is a significant and important challenge in order to improve quality of life for millions and reduce the substantial social-economic costs of the condition. As a complex condition demonstrating high variability and relation to other cardiac conditions, the study of AF requires approaches from multiple disciplines including single-cell experimental electrophysiology and computational modeling. Models of human atrial cells are less well parameterized than those of the human ventricle or other mammal species, largely due to the inherent challenges in patch clamping human atrial cells. Such challenges include, frequently, unphysiologically depolarized resting potentials and thus injection of a compensatory hyperpolarizing current, as well as detecting certain ion currents which may be disrupted by the cell isolation process. The aim of this study was to develop a laboratory specific model of human atrial electrophysiology which reproduces exactly the conditions of isolated-cell experiments, including testing of multiple experimental interventions. Methods: Formulations for the primary ion currents characterized by isolated-cell experiments in the Workman laboratory were fit directly to voltage-clamp data; the fast sodium-current was parameterized based on experiments relating resting membrane potential to maximal action potential upstroke velocity; compensatory hyperpolarizing current was included as a constant applied current. These formulations were integrated with three independent human atrial cell models to provide a family of novel models. Extrapolated intact-cell models were developed through removal of the hyperpolarizing current and introduction of terminal repolarization potassium currents. Results: The isolated-cell models quantitatively reproduced experimentally measured properties of excitation in both control and pharmacological and dynamic-clamp interventions. Comparison of isolated and intact-cell models highlighted the importance of reproducing this cellular environment when comparing experimental and simulation data. Conclusion: We have developed a laboratory specific model of the human atrial cell which directly reproduces the experimental isolated-cell conditions and captures human atrial excitation properties. The model may be particularly useful for directly relating model to experiment, and offers a complementary tool to the available set of human atrial cell models with specific advantages resulting from the congruent input data source.

14.
Pharmacol Res ; 131: 150-163, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29477480

RESUMEN

Evodiae fructus is a widely used herbal drug in traditional Chinese medicine. Evodia extract was found to inhibit hERG channels. The aim of the current study was to identify hERG inhibitors in Evodia extract and to investigate their potential proarrhythmic effects. Dehydroevodiamine (DHE) and hortiamine were identified as IKr (rapid delayed rectifier current) inhibitors in Evodia extract by HPLC-microfractionation and subsequent patch clamp studies on human embryonic kidney cells. DHE and hortiamine inhibited IKr with IC50s of 253.2±26.3nM and 144.8±35.1nM, respectively. In dog ventricular cardiomyocytes, DHE dose-dependently prolonged the action potential duration (APD). Early afterdepolarizations (EADs) were seen in 14, 67, 100, and 67% of cells after 0.01, 0.1, 1 and 10µM DHE, respectively. The proarrhythmic potential of DHE was evaluated in 8 anesthetized rabbits and in 8 chronic atrioventricular block (cAVB) dogs. In rabbits, DHE increased the QT interval significantly by 12±10% (0.05mg/kg/5min) and 60±26% (0.5mg/kg/5min), and induced Torsade de Pointes arrhythmias (TdP, 0.5mg/kg/5min) in 2 rabbits. In cAVB dogs, 0.33mg/kg/5min DHE increased QT duration by 48±10% (P<0.05*) and induced TdP in 2/4 dogs. A higher dose did not induce TdP. In human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs), methanolic extracts of Evodia, DHE and hortiamine dose-dependently prolonged APD. At 3µM DHE and hortiamine induced EADs. hERG inhibition at submicromolar concentrations, APD prolongation and EADs in hiPSC-CMs and dose-dependent proarrhythmic effects of DHE at micromolar plasma concentrations in cAVB dogs should increase awareness regarding proarrhythmic effects of widely used Evodia extracts.


Asunto(s)
Potenciales de Acción/efectos de los fármacos , Alcaloides/efectos adversos , Arritmias Cardíacas/inducido químicamente , Medicamentos Herbarios Chinos/efectos adversos , Canales de Potasio Éter-A-Go-Go/antagonistas & inhibidores , Evodia , Alcaloides/química , Alcaloides/farmacología , Animales , Arritmias Cardíacas/metabolismo , Perros , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Canales de Potasio Éter-A-Go-Go/metabolismo , Evodia/química , Femenino , Células HEK293 , Humanos , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Conejos , Torsades de Pointes/inducido químicamente , Torsades de Pointes/metabolismo , Xenopus
15.
J Midlife Health ; 8(3): 142-144, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28983162

RESUMEN

Periductal stromal sarcoma is a rare low-grade biphasic malignancy arising from periductal breast stroma. This tumor is distinct from phyllodes as it lacks the characteristic leaf-like architecture. Tuberculous mastitis is an uncommon infection seen rarely in the breast parenchyma. We present a rare association between the two diseases, which to the best of our knowledge is the first case reported so far.

18.
Hepatology ; 64(4): 1273-88, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27486864

RESUMEN

UNLABELLED: Bone marrow (BM) is a reservoir for immune and hematopoietic cells and critical for tissue repair and regeneration. All of these functions are severely altered in cirrhosis. We investigated the cellular and functional state of BM in cirrhosis patients. We studied the histological, cellular, and molecular changes in BM of cirrhosis patients (n = 168) and controls (n = 44). Hematopoietic stem cells (HSCs) and associated niche cells, mesenchymal stem cells, Schwann cells, neural fibers, and endothelial cells were evaluated by immunohistochemistry. Cytokines and growth factors were analyzed in peripheral blood and BM plasma. Cirrhotic BM showed an inverse correlation between cluster of differentiation 34+HSCs and Model of End-Stage Liver Disease (ρ = -0.582, P < 0.001) and Child's scores (P < 0.038). BMs of cirrhosis patients with higher Model of End-Stage Liver Disease (>15) showed significantly decreased HSCs, mesenchymal stem cells, Schwann cells, and neural fibers; increased interleukin-1ß (P = 0.004), tumor necrosis factor-α (P = 0.040), and interferon-γ (P = 0.03); and decreased oncostatin M (P = 0.04), stem cell factor (P = 0.05), and stromal cell-derived factor 1 (P = 0.03) compared to those with lower Model of End-Stage Liver Disease scores (≤15). The cluster of differentiation 34+ cell population was a predictor for the development of sepsis (P < 0.001), and per unit loss increased the probability of sepsis by 16%. Cirrhosis patients with fewer HSCs had lower hemoglobin (P = 0.05) and platelet counts (P = 0.05) and showed early graft dysfunction. CONCLUSIONS: Increasing severity of cirrhosis causes derangement of the hematopoietic niche and loss of HSCs, contributing to the hematological and immunological dysfunctions and reduced potential for regeneration; restoring BM functions could provide new therapeutic options in cirrhosis. (Hepatology 2016;64:1273-1288).


Asunto(s)
Células de la Médula Ósea/patología , Células Madre Hematopoyéticas/patología , Cirrosis Hepática/patología , Nicho de Células Madre , Células Madre/patología , Adulto , Enfermedad Hepática en Estado Terminal , Femenino , Humanos , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad
19.
Planta Med ; 82(11-12): 1009-15, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27145237

RESUMEN

Human ether-a-go-go-related gene channel blocking is associated with QT interval prolongation and increased risk of potentially fatal arrhythmias. As natural products keep increasing in popularity, there is an urgent need for studies assessing human ether-a-go-go-related gene channel-related cardiotoxic risks. We selected 49 plant species based on the results of a pharmacophore-based virtual screening campaign, in parallel with a literature data survey concerning highly consumed herbal medicines with reported cardiac liabilities. Lead-like enhanced extracts were prepared, an initial in vitro screening was performed at 100 µg/mL by voltage clamp on Xenopus oocytes, and five human ether-a-go-go-related gene channel blocking extracts were identified. In accordance to the six virtually predicted alkaloids, the root extract of Carapichea ipecacuanha inhibited human ether-a-go-go-related gene channel currents by 32.5 %. A phytochemical workflow resulted in the isolation and identification of five out of the six virtually predicted alkaloids. All isolates blocked human ether-a-go-go-related gene channel currents to different extents. The major ipecac constituents emetine (1) and cephaeline (2) showed IC50 values of 21.4 and 5.3 µM, respectively, measured by whole-cell patch clamp in HEK293 cells. This is the first report on human ether-a-go-go-related gene channel blockers from C. ipecacuanha. Its roots and rhizomes are used to produce different pharmacopeial ipecac preparations that are mainly used as emetics for poisoning treatment. Our findings raise further questions regarding the safety and over-the-counter appropriateness of these herbal products.


Asunto(s)
Alcaloides/farmacología , Cephaelis/química , Canales de Potasio Éter-A-Go-Go/antagonistas & inhibidores , Ipeca/farmacología , Alcaloides/química , Alcaloides/aislamiento & purificación , Animales , Simulación por Computador , Humanos , Ipeca/química , Estructura Molecular , Xenopus laevis
20.
PLoS One ; 11(3): e0150957, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26975046

RESUMEN

Ultraviolet (UV) irradiation is advantageous as a sterilization technique in the biopharmaceutical industry since it is capable of targeting non-enveloped viruses that are typically challenging to destroy, as well as smaller viruses that can be difficult to remove via conventional separation techniques. In this work, we investigated the influence of oxygen in the media during UV irradiation and characterized the effect on chemical composition using NMR and LC-MS, as well as the ability of the irradiated media to support cell culture. Chemically defined Chinese hamster ovary cell growth media was irradiated at high fluences in a continuous-flow UV reactor. UV-irradiation caused the depletion of pyridoxamine, pyridoxine, pyruvate, riboflavin, tryptophan, and tyrosine; and accumulation of acetate, formate, kynurenine, lumichrome, and sarcosine. Pyridoxamine was the only compound to undergo complete degradation within the fluences considered; complete depletion of pyridoxamine was observed at 200 mJ/cm2. Although in both oxygen- and nitrogen-saturated media, the cell culture performance was affected at fluences above 200 mJ/cm2, there was less of an impact on cell culture performance in the nitrogen-saturated media. Based on these results, minimization of oxygen in cell culture media prior to UV treatment is recommended to minimize the negative impact on sensitive media.


Asunto(s)
Medios de Cultivo/química , Oxígeno/química , Rayos Ultravioleta , Animales , Células CHO , Cricetinae , Cricetulus
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...