Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 47
Filtrar
1.
Histopathology ; 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38485464

RESUMO

AIMS: Tumour grading is an essential part of the pathologic assessment that promotes patient management. The International Association for the Study of Lung Cancer (IASLC) proposed a grading system for non-mucinous lung adenocarcinoma in 2020. We aimed to validate the prognostic impact of this novel grading system on overall survival (OS) and recurrence-free survival (RFS) based on literature data. METHODS AND RESULTS: The review protocol was registered in PROSPERO (CRD42023396059). We aimed to identify randomized or non-randomized controlled trials published after 2020 comparing different IASLC grade categories in Medline, Embase, and CENTRAL. Hazard ratios (HRs) with 95% confidence intervals (CIs) of OS and RFS were pooled and the Quality In Prognosis Studies (QUIPS) tool was used to assess the risk of bias in the included studies. Ten articles were eligible for this review. Regarding OS estimates, grade 1 lung adenocarcinomas were better than grade 3 both in univariate and multivariate analyses (HROSuni = 0.19, 95% CI: 0.05-0.66, p = 0.009; HROSmulti = 0.21, 95% CI: 0.12-0.38, p < 0.001). Regarding RFS estimates, grade 3 adenocarcinomas had a worse prognosis than grade 1 in multivariate analysis (HRRFSmulti : 0.22, 95% CI: 0.14-0.35, p < 0.001). CONCLUSION: The literature data and the result of our meta-analysis demonstrate the prognostic relevance of the IASLC grading system. This supports the inclusion of this prognostic parameter in daily routine worldwide.

2.
Graefes Arch Clin Exp Ophthalmol ; 262(5): 1591-1598, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38038730

RESUMO

AIM: Migraine is a chronic neurovascular disease that affects the trigeminovascular system. The purpose of this study was to evaluate corneal subbasal nerve fibers, dendritic cells and to measure tear film parameters in migraine. PATIENTS AND METHODS: 87 eyes of 44 patients suffering from migraine with a mean age of 33.23 ± 11.41 years were included in our study. 25 age-matched controls (mean age of 30.16 ± 12.59 years; P = 0.162) were recruited. The corneal subbasal plexus and the dendritic cells (DC) were analyzed using in vivo confocal microscopy (Heidelberg Retina Tomograph II Rostock Cornea Module; Heidelberg Engineering GmbH), and the tear film was imaged using LacryDiag (Quantel Medical, France). RESULTS: Regarding the subbasal nerve fibers of the cornea, none of the examined parameters differed significantly in migraine patients from controls. We found a significant increase in the corneal DC density (P < 0.0001) and DC area (P < 0.0001) in migraine patients compared to healthy volunteers. DC density showed a positive correlation with the monthly attack frequency (r = 0.32, P = 0.041) and the DC area a negative correlation with corneal nerve branch density (r = -0.233, P = 0.039), nerve fiber length (r = -0.232, P = 0.04) and total branch density (r = -0.233, P = 0.039). Using LacryDiag a significant loss of Meibomian gland area could be detected on the superior eyelid (P = 0.005) in migraine. CONCLUSIONS: Our results suggest the presence of neuroinflammation in the cornea of migraine patients affecting the peripheral trigeminal system. Dendritic cells surrounding the subbasal plexus may be involved in the activation and modulation of pain in migraine.

3.
Int J Mol Sci ; 24(20)2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37894987

RESUMO

Type-2 ryanodine receptor (RyR2) is the major Ca2+ release channel of the cardiac sarcoplasmic reticulum (SR) that controls the rhythm and strength of the heartbeat, but its malfunction may generate severe arrhythmia leading to sudden cardiac death or heart failure. S4938F-RyR2 mutation in the carboxyl-terminal was expressed in human induced pluripotent stem cells derived cardiomyocytes (hiPSC-CMs) using CRISPR/Cas9 gene-editing technique. Ca2+ signaling and electrophysiological properties of beating cardiomyocytes carrying the mutation were studied using total internal reflection fluorescence microscopy (TIRF) and patch clamp technique. In mutant cells, L-type Ca2+ currents (ICa), measured either by depolarizations to zero mV or repolarizations from +100 mV to -50 mV, and their activated Ca2+ transients were significantly smaller, despite their larger caffeine-triggered Ca2+ release signals compared to wild type (WT) cells, suggesting ICa-induced Ca2+ release (CICR) was compromised. The larger SR Ca2+ content of S4938F-RyR2 cells may underlie the higher frequency of spontaneously occurring Ca2+ sparks and Ca2+ transients and their arrhythmogenic phenotype.


Assuntos
Sinalização do Cálcio , Células-Tronco Pluripotentes Induzidas , Humanos , Arritmias Cardíacas/genética , Arritmias Cardíacas/metabolismo , Cálcio/metabolismo , Sinalização do Cálcio/fisiologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Mutação , Miócitos Cardíacos/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Retículo Sarcoplasmático/metabolismo
4.
Virchows Arch ; 483(3): 393-404, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37555982

RESUMO

The prognostic markers of lung squamous cell carcinoma (LSCC) are less investigated. The aim of our study was to evaluate tumour budding (TB), minimal cell nest size, nuclear diameter (ND), and spread through air spaces (STAS) among patients with resected LSCC, semi-quantitatively. Furthermore, we aimed to identify a grading system for the best prognostic stratification of LSCC. Patients who underwent surgical resection at the Department of Surgery, University of Szeged between 2010 and 2016 were included. Follow-up data were collected from medical charts. Morphological characteristics were recorded from histologic revision of slides. Kaplan-Meier analysis, log rank test and Cox proportional-hazards model, ROC curve analysis, and intraclass correlation were utilised. Altogether 220 patients were included. In univariate analysis, higher degree of TB, infiltrative tumour border, larger ND, the presence of single cell invasion (SCI) and STAS were associated with adverse prognosis. Based on our results, we proposed an easily applicable grading scheme focusing on TB, ND, and SCI. In multivariate analysis, the proposed grading system (pOS < 0.001, pRFS < 0.001) and STAS (pOS = 0.008, pRFS < 0.001) were independent prognosticators. Compared to the previously introduced grading systems, ROC curve analysis revealed that the proposed grade had the highest AUC values (AUCOS: 0.83, AUCRFS: 0.78). Each category of the proposed grading system has good (ICC: 0.79-0.88) reproducibility. We validated the prognostic impact of TB, SCI, ND, and STAS in LSCC. We recommend a reproducible grading system combining TB, SCI, and ND for proper prognostic stratification of LSCC patients. Further research is required for validation of this grading scheme.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Carcinoma de Células Escamosas , Neoplasias Pulmonares , Humanos , Prognóstico , Reprodutibilidade dos Testes , Gradação de Tumores , Carcinoma de Células Escamosas/patologia , Neoplasias Pulmonares/patologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Pulmão/patologia , Estudos Retrospectivos , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias
5.
Geroscience ; 45(4): 2179-2193, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36879183

RESUMO

Ivermectin, an antiparasitic drug, has been repurposed for COVID-19 treatment during the SARS-CoV-2 pandemic. Although its antiviral efficacy was confirmed early in vitro and in preclinical studies, its clinical efficacy remained ambiguous. Our purpose was to assess the efficacy of ivermectin in terms of time to viral clearance based on the meta-analysis of available clinical trials at the closing date of the data search period, one year after the start of the pandemic. This meta-analysis was reported by following the PRISMA guidelines and by using the PICO format for formulating the question. The study protocol was registered on PROSPERO. Embase, MEDLINE (via PubMed), Cochrane Central Register of Controlled Trials (CENTRAL), bioRvix, and medRvix were searched for human studies of patients receiving ivermectin therapy with control groups. No language or publication status restrictions were applied. The search ended on 1/31/2021 exactly one year after WHO declared the public health emergency on novel coronavirus. The meta-analysis of three trials involving 382 patients revealed that the mean time to viral clearance was 5.74 days shorter in case of ivermectin treatment compared to the control groups [WMD = -5.74, 95% CI (-11.1, -0.39), p = 0.036]. Ivermectin has significantly reduced the time to viral clearance in mild to moderate COVID-19 diseases compared to control groups. However, more eligible studies are needed for analysis to increase the quality of evidence of ivermectin use in COVID-19.


Assuntos
COVID-19 , Humanos , Ivermectina/uso terapêutico , SARS-CoV-2 , Tratamento Farmacológico da COVID-19 , Resultado do Tratamento
6.
Elife ; 122023 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-36815557

RESUMO

The health benefits of regular physical exercise are well known. Even so, there is increasing evidence that the exercise regimes of elite athletes can evoke cardiac arrhythmias including ventricular fibrillation and even sudden cardiac death (SCD). The mechanism of exercise-induced arrhythmia and SCD is poorly understood. Here, we show that chronic training in a canine model (12 sedentary and 12 trained dogs) that mimics the regime of elite athletes induces electrophysiological remodeling (measured by ECG, patch-clamp, and immunocytochemical techniques) resulting in increases of both the trigger and the substrate for ventricular arrhythmias. Thus, 4 months sustained training lengthened ventricular repolarization (QTc: 237.1±3.4 ms vs. 213.6±2.8 ms, n=12; APD90: 472.8±29.6 ms vs. 370.1±32.7 ms, n=29 vs. 25), decreased transient outward potassium current (6.4±0.5 pA/pF vs. 8.8±0.9 pA/pF at 50 mV, n=54 vs. 42), and increased the short-term variability of repolarization (29.5±3.8 ms vs. 17.5±4.0 ms, n=27 vs. 18). Left ventricular fibrosis and HCN4 protein expression were also enhanced. These changes were associated with enhanced ectopic activity (number of escape beats from 0/hr to 29.7±20.3/hr) in vivo and arrhythmia susceptibility (elicited ventricular fibrillation: 3 of 10 sedentary dogs vs. 6 of 10 trained dogs). Our findings provide in vivo, cellular electrophysiological and molecular biological evidence for the enhanced susceptibility to ventricular arrhythmia in an experimental large animal model of endurance training.


Assuntos
Arritmias Cardíacas , Fibrilação Ventricular , Cães , Animais , Morte Súbita Cardíaca , Ventrículos do Coração , Modelos Animais
7.
Pathobiology ; 90(2): 104-113, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35947971

RESUMO

INTRODUCTION: The extent of spread through air spaces (STAS) is less investigated among patients with lung adenocarcinoma who underwent sublobar resection. Therefore, we aimed to evaluate the extent of STAS semi-quantitatively, to assess its prognostic impact on overall survival (OS) and recurrence-free survival (RFS), and to investigate the reproducibility of this assessment. METHODS: The number of tumour cell clusters and single tumour cells within air spaces was recorded in three different most prominent areas (200x field of view). The extent of STAS was categorized into three groups, and the presence of free tumour cluster (FTC) was recorded. RESULTS: Sixty-one patients were included. Recurrence was more frequent with higher grade (p = 0.003), presence of lymphovascular invasion (p = 0.027), and presence of STAS of any extent (p = 0.007). In multivariate analysis, presence of FTC (HR: 5.89; 95% CI: 1.63-21.26; p = 0.005) and more pronounced STAS (HR: 7.46; 95% CI: 1.60-34.6; p = 0.01) had adverse impact on OS and RFS, respectively. Concerning reproducibility, excellent agreement was found among STAS parameters (ICC range: 0.92-0.94). DISCUSSION: More extensive STAS is an unfavourable prognostic factor in adenocarcinomas treated with sublobar resection. As the evaluation of extent of STAS is reproducible, further investigation is required to gather more evidence.


Assuntos
Adenocarcinoma de Pulmão , Adenocarcinoma , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/cirurgia , Reprodutibilidade dos Testes , Invasividade Neoplásica , Adenocarcinoma de Pulmão/cirurgia , Adenocarcinoma de Pulmão/patologia , Adenocarcinoma/diagnóstico , Adenocarcinoma/cirurgia , Adenocarcinoma/patologia , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/cirurgia , Estadiamento de Neoplasias , Estudos Retrospectivos
8.
Orv Hetil ; 163(52): 2062-2066, 2022 Dec 25.
Artigo em Húngaro | MEDLINE | ID: mdl-36566438

RESUMO

INTRODUCTION: In our study, we aimed to investigate whether the COVID-19 infection itself or the vaccination against it affect the differentiation of T cells in the thymus, and whether the reduction in T cell counts observed in the blood of COVID-19-infected individuals is also observed at the tissue level in the thymus. METHOD: Data from a total of 55 thymectomy patients were processed to create three groups: 1) the pre-COVID-19 (PC) group included 22 patients, 12 women and 10 men, who underwent thymectomy between 2008 and 2013; 2) in the no-COVID-19 (NC) group (patients without verified infection or vaccination), 20 patients, 11 women and 9 men, underwent thymectomy in 2020-2021; 3) the vaccinated or infected COVID-19 (VIC) group included 13 patients, 4 women and 9 men, who underwent thymectomy also in 2020-2021. The pathological samples were immunohistochemically tested for CD4, CD8, CD25 and FOXP3 to verify the helper, cytotoxic and regulatory T cells. RESULTS: The VIC group had significantly lower values for CD4, compared to the PC and NC groups. The FOXP3 value was significantly lower in the VIC and NC groups compared to the PC group. No significant differences were found for CD8 and CD25 between the groups studied. DISCUSSION: The COVID-19 infection or vaccination affects the T cell composition of the thymus. Decreased expression of CD4 has been demonstrated in the VIC group, which confirms a decrease in the T cell counts that also occurs in the thymus. The low FOXP3 levels observed in the NC group during the COVID-19 era, compared to the PC group, may be indicative of a high rate of asymptomatic coronavirus infections and a worsening of immunetolerance. CONCLUSION: First in the world, we have verified that the helper T cell composition of the thymus in COVID-19 infection era is reduced, and in the asymptomatic patients the immune function is decreased as well. Orv Hetil. 2022; 163(52): 2062-2066.


Assuntos
COVID-19 , Pandemias , Linfócitos T , Timo , Feminino , Humanos , Masculino , COVID-19/imunologia , COVID-19/prevenção & controle , Fatores de Transcrição Forkhead/metabolismo , Timo/imunologia , Contagem de Linfócitos , Linfócitos T/imunologia , Vacinação
9.
Sci Rep ; 12(1): 21830, 2022 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-36528651

RESUMO

Sinus node (SN) pacemaking is based on a coupling between surface membrane ion-channels and intracellular Ca2+-handling. The fundamental role of the inward Na+/Ca2+ exchanger (NCX) is firmly established. However, little is known about the reverse mode exchange. A simulation study attributed important role to reverse NCX activity, however experimental evidence is still missing. Whole-cell and perforated patch-clamp experiments were performed on rabbit SN cells supplemented with fluorescent Ca2+-tracking. We established 2 and 8 mM pipette NaCl groups to suppress and enable reverse NCX. NCX was assessed by specific block with 1 µM ORM-10962. Mechanistic simulations were performed by Maltsev-Lakatta minimal computational SN model. Active reverse NCX resulted in larger Ca2+-transient amplitude with larger SR Ca2+-content. Spontaneous action potential (AP) frequency increased with 8 mM NaCl. When reverse NCX was facilitated by 1 µM strophantin the Ca2+i and spontaneous rate increased. ORM-10962 applied prior to strophantin prevented Ca2+i and AP cycle change. Computational simulations indicated gradually increasing reverse NCX current, Ca2+i and heart rate with increasing Na+i. Our results provide further evidence for the role of reverse NCX in SN pacemaking. The reverse NCX activity may provide additional Ca2+-influx that could increase SR Ca2+-content, which consequently leads to enhanced pacemaking activity.


Assuntos
Nó Sinoatrial , Trocador de Sódio e Cálcio , Animais , Coelhos , Nó Sinoatrial/metabolismo , Cloreto de Sódio , Miócitos Cardíacos/metabolismo , Cálcio/metabolismo
10.
Int J Mol Sci ; 23(23)2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36498977

RESUMO

Life-long stable heart function requires a critical balance of intracellular Ca2+. Several ion channels and pumps cooperate in a complex machinery that controls the influx, release, and efflux of Ca2+. Probably one of the most interesting and most complex players of this crosstalk is the Na+/Ca2+ exchanger, which represents the main Ca2+ efflux mechanism; however, under some circumstances, it can also bring Ca2+ into the cell. Therefore, the inhibition of the Na+/Ca2+ exchanger has emerged as one of the most promising possible pharmacological targets to increase Ca2+ levels, to decrease arrhythmogenic depolarizations, and to reduce excessive Ca2+ influx. In line with this, as a response to increasing demand, several more or less selective Na+/Ca2+ exchanger inhibitor compounds have been developed. In the past 20 years, several results have been published regarding the effect of Na+/Ca2+ exchanger inhibition under various circumstances, e.g., species, inhibitor compounds, and experimental conditions; however, the results are often controversial. Does selective Na+/Ca2+ exchanger inhibition have any future in clinical pharmacological practice? In this review, the experimental results of Na+/Ca2+ exchanger inhibition are summarized focusing on the data obtained by novel highly selective inhibitors.


Assuntos
Antiarrítmicos , Trocador de Sódio e Cálcio , Humanos , Trocador de Sódio e Cálcio/metabolismo , Antiarrítmicos/farmacologia , Canais Iônicos/metabolismo , Arritmias Cardíacas/tratamento farmacológico , Transporte Biológico/fisiologia , Cálcio/metabolismo
11.
Surg Oncol ; 44: 101824, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35952403

RESUMO

BACKGROUND: Complete surgical removal is currently considered to be the best treatment option for pulmonary sarcomatoid carcinoma (PSC) especially in early stage operable disease; however, the reported recurrence-free survival is low. Benefits of adjuvant chemotherapy in PSC patients are still controversial, and there is no obvious agreement on the optimal treatment modalities of this disease. Therefore, we aimed to investigate the prognosis in terms of overall survival (OS) in patients with PSC who received adjuvant chemotherapy. METHODS: The review protocol was registered in PROSPERO (CRD42022306084). Patients with PSC who underwent surgical therapy with or without adjuvant chemotherapy were included into the meta-analysis. Hazard ratios (HR) with 95% confidence intervals (CIs) for OS were pooled and ROBINS-I tool was used to assess risk of bias of the included studies. RESULTS: We identified four retrospective cohort studies with 6768 records from MEDLINE, Embase, and CENTRAL databases up to 9th September 2021, and altogether 1835 patients were included to the analysis. The present meta-analysis shows that patients receiving adjuvant chemotherapy had a significantly longer OS than patients who underwent surgical treatment alone (HR = 0.5657, 95%CI: 0.4391-0.7290, p < 0.0001). CONCLUSIONS: Despite the limited information on the chemotherapy regimens in the included studies, patients with PSC may benefit from adjuvant chemotherapy. More publications are required to evaluate and compare efficient adjuvant chemotherapy protocols in PSC cases.


Assuntos
Carcinoma , Protocolos de Quimioterapia Combinada Antineoplásica , Carcinoma/cirurgia , Quimioterapia Adjuvante/métodos , Humanos , Estudos Retrospectivos
12.
Front Surg ; 9: 883322, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35669251

RESUMO

Systemic inflammation (SI) is a response of the immune system to infectious or non-infectious injuries that defends the body homeostasis. Every surgical intervention triggers SI, the level of which depends on the extent of damage caused by the surgery. During the first few hours after the damage, the innate or natural immunity, involving neutrophils, macrophages, and natural killer cells, plays a main role in the defense mechanism, but thereafter the adaptive immune response ensues. The number of leukocytes is elevated, the levels of lymphocytes and natural killer cells are reduced, and the cytokines released after surgery correlate with surgical damage. Minimally invasive thoracic surgery procedures induce less inflammatory response and reduce the immune defense in patients to a more moderate level compared with the open surgery procedures; this immunosuppression can be further diminished in spontaneous ventilation cases. The normal functioning of the immune defense is important in controlling the perioperative circulatory tumor cells. Moreover, elevated levels of inflammatory cytokines before immune therapy have a negative impact on the response, and significantly shorten the progression-free survival. Clinically, the lower are the levels of cytokines released during lung surgery, the lesser is the postoperative morbidity, especially pneumonia and wound infection. The return to normal levels of lymphocytes and cytokines occurs faster after spontaneous ventilation surgery. The use of locoregional anesthesia can also reduce SI. Herein, we review the current knowledge on the effects of different operative factors on postoperative SI and defense mechanism in lung cancer surgery.

13.
Int J Mol Sci ; 23(9)2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35562924

RESUMO

Metabolomics strategies are widely used to examine obesity and type 2 diabetes (T2D). Patients with obesity (n = 31) or T2D (n = 26) and sex- and age-matched controls (n = 28) were recruited, and serum and tear samples were collected. The concentration of 23 amino acids and 10 biogenic amines in serum and tear samples was analyzed. Statistical analysis and Pearson correlation analysis along with network analysis were carried out. Compared to controls, changes in the level of 6 analytes in the obese group and of 10 analytes in the T2D group were statistically significant. For obesity, the energy generation, while for T2D, the involvement of NO synthesis and its relation to insulin signaling and inflammation, were characteristic. We found that BCAA and glutamine metabolism, urea cycle, and beta-oxidation make up crucial parts of the metabolic changes in T2D. According to our data, the retromer-mediated retrograde transport, the ethanolamine metabolism, and, consequently, the endocannabinoid signaling and phospholipid metabolism were characteristic of both conditions and can be relevant pathways to understanding and treating insulin resistance. By providing potential therapeutic targets and new starting points for mechanistic studies, our results emphasize the importance of complex data analysis procedures to better understand the pathomechanism of obesity and diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Diabetes Mellitus Tipo 2/metabolismo , Humanos , Insulina , Metabolômica , Obesidade
14.
Pharmaceuticals (Basel) ; 15(3)2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35337111

RESUMO

Sinus pacemaking is based on tight cooperation of intracellular Ca2+ handling and surface membrane ion channels. An important player of this synergistic crosstalk could be the small-conductance Ca2+-activated K+-channel (ISK) that could contribute to the sinoatrial node (SAN) pacemaking driven by the intracellular Ca2+ changes under normal conditions and beta-adrenergic activation, however, the exact role is not fully clarified. SK2 channel expression was verified by immunoblot technique in rabbit SAN cells. Ionic currents and action potentials were measured by patch-clamp technique. The ECG R-R intervals were obtained by Langendorff-perfusion method on a rabbit heart. Apamin, a selective inhibitor of SK channels, was used during the experiments. Patch-clamp experiments revealed an apamin-sensitive current. When 100 nM apamin was applied, we found no change in the action potential nor in the ECG R-R interval. In experiments where isoproterenol was employed, apamin increased the cycle length of the SAN action potentials and enhanced the ECG R-R interval. Apamin did not amplify the cycle length variability or ECG R-R interval variability. Our data indicate that ISK has no role under normal condition, however, it moderately contributes to the SAN automaticity under beta-adrenergic activation.

15.
Br J Pharmacol ; 179(13): 3382-3402, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35106755

RESUMO

BACKGROUND AND PURPOSE: The aim of the present study was to study the antiarrhythmic effects and cellular mechanisms of desethylamiodarone (DEA), the main metabolite of amiodarone (AMIO), following acute and chronic 4-week oral treatments (25-50 mg·kg-1 ·day-1 ). EXPERIMENTAL APPROACH: The antiarrhythmic effects of acute iv. (10 mg·kg-1 ) and chronic oral (4 weeks, 25 mg·kg-1 ·day-1 ) administration of DEA were assessed in carbachol and tachypacing-induced dog atrial fibrillation models. Action potentials were recorded from atrial and right ventricular tissue following acute (10 µM) and chronic (p.o. 4 weeks, 50 mg·kg-1 ·day-1 ) DEA application using the conventional microelectrode technique. Ionic currents were measured by the whole cell configuration of the patch clamp technique in isolated left ventricular myocytes. Pharmacokinetic studies were performed following a single intravenous dose (25 mg·kg-1 ) of AMIO and DEA intravenously and orally. In chronic (91-day) toxicological investigations, DEA and AMIO were administered in the oral dose of 25 mg·kg-1 ·day-1 ). KEY RESULTS: DEA exerted marked antiarrhythmic effects in both canine atrial fibrillation models. Both acute and chronic DEA administration prolonged action potential duration in atrial and ventricular muscle without any changes detected in Purkinje fibres. DEA decreased the amplitude of several outward potassium currents such as IKr , IKs , IK1 , Ito , and IKACh , while the ICaL and late INa inward currents were also significantly depressed. Better drug bioavailability and higher volume of distribution for DEA were observed compared to AMIO. No neutropenia and less severe pulmonary fibrosis was found following DEA compared to that of AMIO administration. CONCLUSION AND IMPLICATIONS: Chronic DEA treatment in animal experiments has marked antiarrhythmic and electrophysiological effects with better pharmacokinetics and lower toxicity than its parent compound. These results suggest that the active metabolite, DEA, should be considered for clinical trials as a possible new, more favourable option for the treatment of cardiac arrhythmias including atrial fibrillation.


Assuntos
Amiodarona , Fibrilação Atrial , Potenciais de Ação , Amiodarona/análogos & derivados , Amiodarona/farmacologia , Animais , Antiarrítmicos/farmacologia , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/metabolismo , Cães , Átrios do Coração , Miócitos Cardíacos
16.
Biomedicines ; 10(2)2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-35203454

RESUMO

Vagal nerve stimulation (VNS) has a meaningful basis as a potentially effective treatment for heart failure with reduced ejection fraction. There is an ongoing VNS randomized study, and four studies are completed. However, relatively little is known about the effect of acetylcholine (ACh) on repolarization in human ventricular cardiomyocytes, as well as the effect of ACh on the rapid component of the delayed rectifier K+ current (IKr). Here, we investigated the effect of ACh on the action potential parameters in human ventricular preparations and on IKr in human induced pluripotent stem-cell-derived cardiomyocytes (hiPSC-CMs). Using standard microelectrode technique, we demonstrated that ACh (5 µM) significantly increased the action potential duration in human left ventricular myocardial slices. ACh (5 µM) also prolonged repolarization in a human Purkinje fiber and a papillary muscle. Optical mapping revealed that ACh increased the action potential duration in human left ventricular myocardial slices and that the effect was dose-dependent. Perforated patch clamp experiments demonstrated action potential prolongation and a significant decrease in IKr by ACh (5 µM) in hiPSC-CMs. Computer simulations of the electrical activity of a human ventricular cardiomyocyte showed an increase in action potential duration upon implementation of the experimentally observed ACh-induced changes in the fully activated conductance and steady-state activation of IKr. Our findings support the hypothesis that ACh can influence the repolarization in human ventricular cardiomyocytes by at least changes in IKr.

17.
Can J Physiol Pharmacol ; 99(11): 1159-1174, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34636643

RESUMO

In clinical trials of heart failure reduced ejection fraction (HFrEF), ivabradine seemed to be an effective heart rate lowering agent associated with lower risk of cardiovascular death. In contrast, ivabradine failed to improve cardiovascular outcomes in heart failure preserved ejection fraction (HFpEF) despite the significant effect on heart rate. This meta-analysis is the first to compare the effects of ivabradine on heart rate and mortality parameters in HFpEF versus HFrEF. We screened three databases: PubMed, Embase, and Cochrane Library. The outcomes of these studies were mortality, reduction in heart rate, and left ventricular function improvement. We compared the efficacy of ivabradine treatment in HFpEF versus HFrEF. Heart rate analysis of pooled data showed decrease in both HFrEF (-17.646 beats/min) and HFpEF (-11.434 beats/min), and a tendency to have stronger bradycardic effect in HFrEF (p = 0.094) in randomized clinical trials. Left ventricular ejection fraction analysis revealed significant improvement in HFrEF (5.936, 95% CI: [4.199-7.672], p < 0.001) when compared with placebo (p < 0.001). We found that ivabradine significantly improves left ventricular performance in HFrEF, at the same time it exerts a tendency to have improved bradycardic effect in HFrEF. These disparate effects of ivabradine and the higher prevalence of non-cardiac comorbidities in HFpEF may explain the observed beneficial effects in HFrEF and the unchanged outcomes in HFpEF patients after ivabradine treatment.


Assuntos
Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/fisiopatologia , Ivabradina/farmacologia , Ivabradina/uso terapêutico , Volume Sistólico , Função Ventricular Esquerda , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Insuficiência Cardíaca/mortalidade , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
18.
Orv Hetil ; 162(38): 1541-1547, 2021 09 19.
Artigo em Húngaro | MEDLINE | ID: mdl-34537719

RESUMO

Összefoglaló. A nekrotizáló sarcoid granulomatosis a granulomatosus pulmonalis angitisek közé tartozó, ritka kórkép. Egyesek a sarcoidosis variánsának, mások primer pulmonalis vasculitisnek tartják. A kórkép klinikai és patológiai jellegzetességeit két eset bemutatásával ismertetjük. A 20 éves nobeteg sürgosséggel került pulmonológiai osztályra száraz köhögés, jobb oldali, mély belégzéssel összefüggo mellkasi fájdalom és láz miatt, a 63 éves férfi beteget pedig pneumoniát követo kontroll-mellkasröntgenfelvételen látott elváltozás kivizsgálása során észlelték. Az autoimmun panel vizsgálata, a mikrobiológiai tesztek mindkét betegnél negatívnak bizonyultak, a légzésfunkciós vizsgálat és a bronchoszkópos vizsgálat nem talált eltérést. A mellkas-CT-felvételen lágyrész-denzitású nodulusok látszottak egyoldali dominanciával, a folyamatot nem kísérte a hilusi nyirokcsomók szimmetrikus megnagyobbodása. A nodulusok szövettani vizsgálata vált indokolttá, melyet videoasszisztált torakoszkópos tüdoreszekciós mintavétellel biztosítottak. Mikroszkóposan a tüdoparenchymában gócos nekrózisokat, a környezetükben el nem sajtosodó epitheloid sejtes granulomatosus gócokat, az átfutó artériákban pedig granulomatosus arteritist láttak; a klinikai adatok figyelembevételével a tüdo nekrotizáló sarcoid granulomatosisa diagnózisát állították fel. A tüdobetegség mindkét betegnél egy év alatt spontán regrediált. Az irodalom adatait és az eseteket összegezve, a tüdo nekrotizáló sarcoid granulomatosisában mikrobiológiai vizsgálatokkal nem igazolható tüdofertozés, és az immunológiai kivizsgálás sem tár fel szisztémás autoimmun betegséget; a diagnózis a klinikai kép és a képalkotó vizsgálatok alapján indikált szövettani vizsgálattal állítható fel. A betegség szteroidkezelésre jól reagál, de elofordul spontán regresszió is, az utóbbira láttunk példát. Bár az entitás átmenetet képez a nekrotizáló vasculitisek és a sarcoidosis között, egyre több érv szól amellett, hogy a sarcoidosis spektrumába tartozik. Orv Hetil. 2021; 162(38): 1541-1547. Summary. Necrotizing sarcoid granulomatosis is a rare entity currently classified as a subtype of granulomatous pulmonary angiitis. It is considered to be either a variant of sarcoidosis or a primary pulmonary angiitis. Two cases are demonstrated to present its clinical and pathological features. A 20-year-old female patient was admitted to the department of pulmonology with dry cough, right-sided chest pain during hyperventilation and fever. A 63-year-old male patient was observed with a right-sided lesion on chest X-ray after pneumonia. In both cases, autoimmune panel examination, microbiology tests, spirometry function test and bronchoscopy were unremarkable. Chest CT scans have revealed nodules with soft-tissue density without bilateral hilar lymphadenopathy. In order to clarify the diagnosis, video-assisted thoracoscopic resection (biopsy) was performed. Microscopically, parenchymal focal necrosis with adjacent to non-caseating granulomas and granulomatous angiitis were detected. In both cases, spontaneous remission occurred within a year. Histological examination - integrated with clinical data and radiological tests' results - is the gold standard form of evaluation to confirm necrotizing sarcoid granulomatosis; furthermore, exclusion of pneumonia and autoimmune diseases are also required. The disease responds well to corticosteroids; moreover, spontaneous remission is often reported, as it happened in both cases. Necrotizing sarcoid granulomatosis is a transition between necrotizing vasculitides and sarcoidosis; although more and more evidence appears supporting the fact that necrotizing sarcoid granulomatosis may belong to the spectrum of sarcoidosis. Orv Hetil. 2021; 162(38): 1541-1547.


Assuntos
Sarcoidose , Adulto , Feminino , Febre , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Adulto Jovem
19.
Sci Rep ; 11(1): 16652, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34404848

RESUMO

Cardiac alternans have crucial importance in the onset of ventricular fibrillation. The early explanation for alternans development was the voltage-driven mechanism, where the action potential (AP) restitution steepness was considered as crucial determining factor. Recent results suggest that restitution slope is an inadequate predictor for alternans development, but several studies still claim the role of membrane potential as underlying mechanism of alternans. These controversial data indicate that the relationship of restitution and alternans development is not completely understood. APs were measured by conventional microelectrode technique from canine right ventricular papillary muscles. Ionic currents combined with fluorescent measurements were recorded by patch-clamp technique. APs combined with fluorescent measurements were monitored by sharp microelectrodes. Rapid pacing evoked restitution-independent AP duration (APD) alternans. When non-alternating AP voltage command was used, Ca2+i-transient (CaT) alternans were not observed. When alternating rectangular voltage pulses were applied, CaT alternans were proportional to ICaL amplitude alternans. Selective ICaL inhibition did not influence the fast phase of APD restitution. In this study we found that ICaL has minor contribution in shaping the fast phase of restitution curve suggesting that ICaL-if it plays important role in the alternans mechanism-could be an additional factor that attenuates the reliability of APD restitution slope to predict alternans.


Assuntos
Potenciais de Ação , Cálcio/metabolismo , Ventrículos do Coração/fisiopatologia , Fibrilação Ventricular/fisiopatologia , Animais , Sinalização do Cálcio , Cães , Feminino , Ventrículos do Coração/metabolismo , Ventrículos do Coração/patologia , Masculino , Miocárdio/patologia , Fibrilação Ventricular/metabolismo , Fibrilação Ventricular/patologia
20.
Graefes Arch Clin Exp Ophthalmol ; 259(11): 3339-3350, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34283292

RESUMO

PURPOSES: To examine corneal nerve and retinal nerve characteristics of participants with type 2 diabetes mellitus (T2DM) compared with obese participants without diabetes to discover potential nerve vulnerabilities. METHODS: All participants underwent a complete medical examination including a physical examination and blood sample tests. The ophthalmologic examination included best-corrected visual acuity, intraocular pressure, Schirmer test, tear film breakup time, slit-lamp examination, dilated fundus photography, in vivo corneal confocal microscopy (IVCCM), and optical coherence tomography (OCT). RESULTS: The study cohort consisted of 83 eyes of 83 individuals: a group of 44 participants with T2DM, and a control group of 39 obese participants with no history of diabetes. Comparing measurements on the two groups, participants with T2DM had lower values with statistical significance for retinal nerve fiber layer (RNFL) nasal superior thickness (p = 0.010) and three corneal nerve (CN) parameters: fiber length (p = 0.025), total branch density (p = 0.013), and fiber area (p = 0.009). There was a borderline significant difference in CN fiber width (p = 0.051) and RNFL nasal inferior thickness (p = 0.056). No other significant differences were observed in the IVCCM and OCT parameters. No statistically significant correlation was found between CN and RNFL parameters. CONCLUSIONS: Progression from a pre-diabetic obese state to a T2DM condition might entail a loss or diminishment of certain corneal nerve fibers or retinal nerve fibers, but not necessarily a loss of both corneal and retinal nerve fibers simultaneously. Using IVCCM and OCT together enables monitoring of both corneal and retinal health of the eye.


Assuntos
Diabetes Mellitus Tipo 2 , Tomografia de Coerência Óptica , Estudos Transversais , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Humanos , Microscopia Confocal , Obesidade/complicações , Obesidade/diagnóstico , Células Ganglionares da Retina
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...