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1.
AIDS Care ; 35(8): 1215-1223, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-33745403

RESUMO

Chronic pain is a common comorbidity in people with HIV (PWH), with prevalence estimates of 25-85%. Research in this area is growing, but significant gaps remain. A Global Task Force of HIV experts was organized to brainstorm a scientific agenda and identify measurement domains critical to advancing research in this field. Experts were identified through literature searches and snowball sampling. Two online questionnaires were developed by Task Force members. Questionnaire 1 asked participants to identify knowledge gaps in the field of HIV and chronic pain and identify measurement domains in studies of chronic pain in PWH. Responses were ranked in order of importance in Questionnaire 2, which was followed by a group discussion. 29 experts completed Questionnaire 1, 25 completed Questionnaire 2, and 21 participated in the group. Many important clinical and research priorities emerged, including the need to examine etiologies of chronic pain in PWH. Pain-related measurement domains were discussed, with a primary focus on domains that could be assessed in a standardized manner across various cohorts that include PWH in different countries. We collaboratively identified clinical and research priorities, as well as gaps in standardization of measurement domains, that can be used to move the field forward.


Assuntos
Dor Crônica , Infecções por HIV , Humanos , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Dor Crônica/epidemiologia , Comorbidade
2.
J Physiol Pharmacol ; 70(1)2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-31019121

RESUMO

The Lambeth Conventions (LC I), a landmark guidance document for arrhythmia research was updated and arrhythmia definitions were changed in the new Lambeth Conventions II (LC II). This study examined whether the arrhythmia definitions of LC I and LC II yield the same qualitative results and whether LC II improves inter-observer agreement. Two independent investigators performed blinded arrhythmia analysis of the electrocardiograms of isolated, Langendorff rat hearts subjected to regional ischemia and perfused with Class I antiarrhythmics with 3 or 5 mM K+ in the perfusate. Data obtained with arrhythmia definitions of LC I and LC II were compared within and between observers. Applying ventricular fibrillation (VF) definition of LC II significantly increased VF incidence and reduced VF onset time irrespective of treatment by detecting 'de novo' VF episodes not found by LC I. LC II reduced the number of ventricular tachycardia (VT) episodes and simultaneously increased the number of VF episodes as compared with the respective values obtained according to LC I. Using VF definition of LC II masked the significant antifibrillatory effects of flecainide and the high K+ concentration identified with the VF definition of LC I. When VF incidence was tested, a very strong inter-observer agreement was found according to LC I, whereas using VF definition of LC II reduced inter-observer agreement. It is concluded that LC II shifts some tachyarrhythmias from VT to VF class, and thus results obtained by arrhythmia definitions of LC I and LC II are not compatible; VF definition of LC II may change the conclusion of pharmacological, physiological and pathophysiological arrhythmia investigations and may reduce inter-observer agreement. Thus, VT and VF definitions of LC II should be amended in order to increase compatibility and inter-observer agreement.


Assuntos
Taquicardia Ventricular/fisiopatologia , Fibrilação Ventricular/fisiopatologia , Animais , Eletrocardiografia , Humanos , Masculino , Isquemia Miocárdica/fisiopatologia , Variações Dependentes do Observador , Ratos
3.
Epidemiol Infect ; 147: e18, 2018 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-30284525

RESUMO

Chlamydia trachomatis (CT) infections remain highly prevalent. CT reinfection occurs frequently within months after treatment, likely contributing to sustaining the high CT infection prevalence. Sparse studies have suggested CT reinfection is associated with a lower organism load, but it is unclear whether CT load at the time of treatment influences CT reinfection risk. In this study, women presenting for treatment of a positive CT screening test were enrolled, treated and returned for 3- and 6-month follow-up visits. CT organism loads were quantified at each visit. We evaluated for an association of CT bacterial load at initial infection with reinfection risk and investigated factors influencing the CT load at baseline and follow-up in those with CT reinfection. We found no association of initial CT load with reinfection risk. We found a significant decrease in the median log10 CT load from baseline to follow-up in those with reinfection (5.6 CT/ml vs. 4.5 CT/ml; P = 0.015). Upon stratification of reinfected subjects based upon presence or absence of a history of CT infections prior to their infection at the baseline visit, we found a significant decline in the CT load from baseline to follow-up (5.7 CT/ml vs. 4.3 CT/ml; P = 0.021) exclusively in patients with a history of CT infections prior to our study. Our findings suggest repeated CT infections may lead to possible development of partial immunity against CT.

4.
J Physiol Pharmacol ; 67(5): 731-737, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28011953

RESUMO

Hyperventilation reduces partial pressure of CO2 (PCO2) in the blood, which results in hypokalaemia. Hypokalaemia helps the development of the life-threatening torsades de pointes type ventricular arrhythmia (TdP) evoked by repolarization delaying drugs. This implies that hyperventilation may assist the development of proarrhythmic events. Therefore, this study experimentally investigated the effect of hyperventilation on proarrhythmia development during delayed repolarization. Phenylephrine (an α1-adrenoceptor agonist) and clofilium (as a representative repolarization delaying agent inhibiting the rapid component of the delayed rectifier potassium current, IKr) were administered intravenously to pentobarbital-anaesthetized, mechanically ventilated, open chest rabbits. ECG was recorded, and the onset times and incidences of the arrhythmias were determined. Serum K+, pH and PCO2 were measured in arterial blood samples. Clofilium prolonged the rate corrected QT interval. TdP occurred in 15 animals (TdP+ group), and did not occur in 14 animals (TdP- group). We found a strong, positive, linear correlation between serum K+ and PCO2. There was no relationship between the occurrence of TdP and the baseline K+ and PCO2 values. However, a positive, linear correlation was found between the onset time of the first arrhythmias and the K+ and PCO2 values. The regression lines describing the relationship between PCO2 and onset time of first arrhythmias were parallel in the TdP+ and TdP- groups, but the same PCO2 resulted in earlier arrhythmia onset in the TdP+ group than in the TdP- group. We conclude that hyperventilation and hypocapnia with the resultant hypokalaemia assist the multifactorial process of proarrhythmia development during delayed repolarization. This implies that PCO2 and serum K+ should be controlled tightly during mechanical ventilation in experimental investigations and clinical settings when repolarization-delaying drugs are applied.


Assuntos
Arritmias Cardíacas/fisiopatologia , Hiperventilação/fisiopatologia , Hipopotassemia/fisiopatologia , Agonistas de Receptores Adrenérgicos alfa 1/farmacologia , Animais , Antiarrítmicos/farmacologia , Arritmias Cardíacas/sangue , Arritmias Cardíacas/induzido quimicamente , Monitorização Transcutânea dos Gases Sanguíneos , Eletrocardiografia , Hiperventilação/sangue , Hipopotassemia/sangue , Masculino , Fenilefrina/farmacologia , Potássio/sangue , Bloqueadores dos Canais de Potássio/farmacologia , Compostos de Amônio Quaternário/farmacologia , Coelhos , Respiração Artificial
5.
Zootaxa ; 4169(3): 401-434, 2016 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-27701285

RESUMO

In his five publications Nees (1811-1834) described 263 braconid species originating mainly from Germany and, less in number, from a further seven countries in Europe. The braconid species were assigned to 19 genera: twelve have been created by him and the rest (seven genera) by three other authors. The majority of the species (218) remained valid, the rest of the names (45) were placed in synonymy (by other authors). By his descriptions the species and genera are more or less recognizable, nevertheless their redescriptions are promoting their unambiguous recognition. In the first checklist provided, the genera and species are presented following Nees's original denominations and the current valid generic and species names are listed (denoted by an equals (=) sign). In the second checklist, the current valid generic and species names are compared with the original generic and species names. In the third checklist, the braconid species of 16 other authors included in Nees five publications are listed. New author's names for three species are provided: Doryctes leucogaster Ziegler, 1834 (Bacon), Microgaster nigricans Gyllenhal, 1834 and Microplitis sordipes (Ziegler, 1834) (Microgaster); the author of these three species was Nees. The Nees Collection (braconid and other material) was destroyed at the end of the Second World War.


Assuntos
Vespas/classificação , Distribuição Animal , Animais , Lista de Checagem , Ecossistema , Europa (Continente) , Feminino , Masculino
6.
Int J Cardiol ; 203: 543-8, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26580334

RESUMO

The use of inotropes for correcting hemodynamic dysfunction in patients with congestive heart failure has been described over many decades. Drugs such as cardiac glycosides, cathecolamines, phosphodiestherase inhibitors, and calcium sensitizers have been in turn proposed. However, the number of new chemical entities in this therapeutic field has been surprisingly low, and the current selection of drugs is limited. One of the paradigm shifts in the discovery for new inotropes was to focus on 'calcium sensitizers' instead of 'calcium mobilizers'. This was designed to lead to the development of safer inotropes, devoid of the complications that arise due to increased intracellular calcium levels. However, only three such calcium sensitizers have been fully developed over the latest 30 years. Moreover, two of these, levosimendan and pimobendan, have multiple molecular targets and other pharmacologic effects in addition to inotropy, such as peripheral vasodilation. More recently, omecamtiv mecarbil was described, which is believed to have a pure inotropy action that is devoid of pleiotropic effects. When the clinical data of these three calcium sensitizers are compared, it appears that the less pure inotropes have the cutting edge over the purer inotrope, due to additional effects during the treatment of a complex syndrome such as acute congested heart failure. This review aims to answer the question whether calcium sensitization per se is a sufficient strategy for bringing required clinical benefits to patients with heart failure. This review is dedicated to the memory of Heimo Haikala, a true and passionate innovator in this challenging field.


Assuntos
Cálcio da Dieta/uso terapêutico , Cálcio/metabolismo , Insuficiência Cardíaca/tratamento farmacológico , Hemodinâmica/efeitos dos fármacos , Contração Miocárdica/efeitos dos fármacos , Cardiotônicos , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/fisiopatologia , Humanos
7.
J Physiol Pharmacol ; 66(2): 215-26, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25903952

RESUMO

During ischaemia/reperfusion, the rise in [Na(+)](i), induced by simultaneous depression of the Na(+)/K(+)-ATPase and activation of the Na(+)/H(+) exchanger (NHE), shifts the Na(+)/Ca(2+) exchanger (NCX) into reverse transport mode, resulting in Ca(2+)(i)overload, which is a critical factor in enhancing the liability to cardiac arrhythmias. The inhibition of NHE, and recently NCX has been suggested to effectively protect the heart from reperfusion-induced arrhythmias. In this study, we investigated and compared the efficacy of individual or the simultaneous inhibition of the NHE and NCX against reperfusion-induced arrhythmias in Langendorff-perfused rat hearts by applying a commonly used regional ischaemia-reperfusion protocol. The NHE and NCX were inhibited by cariporide and SEA0400 or the novel, more selective ORM-10103, respectively. Arrhythmia diagrams calculated for the reperfusion period were analysed for the incidence and duration of extrasystoles (ESs), ventricular tachycardia (VT) and ventricular fibrillation (VF). NHE inhibition by cariporide was highly efficient in reducing the recorded reperfusion-induced arrhythmias. Following the application of SEA0400 or ORM-10103, the number and duration of arrhythmic periods were efficiently or moderately decreased. While both NCX inhibitors effectively reduced ESs, the most frequently triggered arrhythmias, they exerted limited or no effect on VTs and VFs. Of the NCX inhibitors, ORM-10103 was more effective. Surprisingly, the simultaneous inhibition of the NCX and NHE failed to significantly improve the antiarrhythmic efficacy reached by NCX blockade alone. In conclusion, although principal simultaneous NHE+NCX inhibition should be highly effective against all types of the recorded reperfusion-induced arrhythmias, NCX inhibitors, alone or in combination with cariporide, seem to be moderately suitable to provide satisfactory cardioprotection - at least in the present arrhythmia model. Since ORM-10103 and SEA0400 are known to effectively inhibit after-depolarisations, it is suggested that their efficacy and that of other NCX inhibitors may be higher and more pronounced in the predominantly Ca(2+)(i)-dependent triggered arrhythmias.


Assuntos
Antiarrítmicos/farmacologia , Arritmias Cardíacas/tratamento farmacológico , Trocador de Sódio e Cálcio/antagonistas & inibidores , Trocadores de Sódio-Hidrogênio/antagonistas & inibidores , Compostos de Anilina/farmacologia , Animais , Arritmias Cardíacas/metabolismo , Benzopiranos/farmacologia , Cálcio/metabolismo , Cardiotônicos/farmacologia , Quimioterapia Combinada/métodos , Guanidinas/farmacologia , Masculino , Reperfusão Miocárdica/métodos , Miocárdio/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Éteres Fenílicos/farmacologia , Piridinas/farmacologia , Ratos , Ratos Sprague-Dawley , Sulfonas/farmacologia , Taquicardia Ventricular/tratamento farmacológico , Taquicardia Ventricular/metabolismo , Fibrilação Ventricular/tratamento farmacológico , Fibrilação Ventricular/metabolismo
8.
Acta Physiol Hung ; 101(4): 429-37, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25532954

RESUMO

Capsaicin is a well-known component of red pepper. Recent studies have shown that capsaicin could prevent gastric ulcer provoked by various NSAID-s like acetylsalicylic acid (ASA). Primary objective of this human clinical phase I trial was to investigate whether two different doses of capsaicin co-administered with ASA could alter the inhibitory effect of ASA on platelet aggregation. 15 healthy male subjects were involved in the study and treated orally with 400 µg capsaicin, 800 µg capsaicin, 500 mg ASA, 400 µg capsaicin+500 mg ASA and 800 µg capsaicin+500 mg ASA. Blood was drawn before and 1, 2, 6 and 24 hours after the drug administration. After that epinephrine induced platelet aggregation was measured by optical aggregometry. Between treatments, volunteers had a 6-day wash-out period. Our results showed that capsaicin had no effect on platelet aggregation, while as expected, ASA monotherapy resulted in a significant and clinically effective platelet aggregation inhibition (p ≤ 0.001). The combined ASA-capsaicin therapies reached equivalent effectiveness in platelet aggregation inhibition as ASA monotherapy. Our investigation proved that capsaicin did not influence the inhibitory effect of ASA on platelet aggregation, thus the capsaicin-ASA treatment would combine the antiplatelet effect of ASA with the possible gastroprotection of capsaicin.


Assuntos
Antiulcerosos/administração & dosagem , Aspirina/administração & dosagem , Capsaicina/administração & dosagem , Inibidores da Agregação Plaquetária/administração & dosagem , Agregação Plaquetária/efeitos dos fármacos , Administração Oral , Adolescente , Adulto , Antiulcerosos/sangue , Antiulcerosos/farmacocinética , Aspirina/sangue , Aspirina/farmacocinética , Capsaicina/sangue , Capsaicina/farmacocinética , Interações Medicamentosas , Voluntários Saudáveis , Humanos , Hungria , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/sangue , Inibidores da Agregação Plaquetária/farmacocinética , Testes de Função Plaquetária , Método Simples-Cego , Adulto Jovem
9.
Clin Hemorheol Microcirc ; 56(1): 1-12, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23076007

RESUMO

BACKGROUND: Acetylsalicylic acid (ASA) plays an important role in the treatment and prevention of cardiovascular diseases. Metamizole (MET) is an analgesic and antipyretic medicine, it is not used as an antiplatelet drug. OBJECTIVES: We aimed to examine the antiplatelet effect of MET and the possible interactions between the drugs. METHODS: In our in vitro investigations different concentrations of ASA and MET solutions were added to blood. To examine the interactions MET and ASA were added together. In our in vivo crossover study intravenous MET, oral ASA or both drugs together were administered. Epinephrine and adenosine-diphosphate induced platelet aggregation was determined by optical aggregometry. RESULTS: Epinephrine-induced aggregation was completely inhibited in all ASA and MET concentrations in vitro. Lower, ineffective concentration of MET prevented the antiplatelet effect of ASA. The inhibition was completely restored when higher concentration of ASA was used or when ASA was added first. Our in vivo study showed that in the MET group rapid onset of inhibition was developed and there was no inhibition after one day. In the ASA group platelet aggregation decreased slowly but still had significant inhibitory effect after 72 hours. Combined therapy showed similar changes to the MET group. CONCLUSION: Antiplatelet effect of MET and ASA did not differ significantly in vitro. The observations may indicate a competitive interaction between the two drugs. The in vivo experiments showed that intravenously administered MET is an effective antiplatelet drug and can be considered as a therapeutic alternative, when ASA cannot be used in oral form.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Aspirina/farmacologia , Dipirona/farmacologia , Inibidores da Agregação Plaquetária/farmacologia , Estudos Cross-Over , Interações Medicamentosas , Quimioterapia Combinada , Epinefrina/farmacologia , Feminino , Humanos , Masculino , Agregação Plaquetária/efeitos dos fármacos , Resultado do Tratamento , Adulto Jovem
10.
Clin Hemorheol Microcirc ; 56(1): 13-23, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23089888

RESUMO

Pieces of epidemiological evidence have supported that moderate red wine consumption reduces the risk of cardiovascular diseases (French-paradox). Our previous in vitro experiment has demonstrated favourable hemorheological effects of red wine, alcohol-free red wine extract and ethanol. Thirty-nine healthy, non-smoking male volunteers between 18-40 years were assigned into two groups: control group had drunk water, while red wine group had consumed 2 dl of red wine each day at dinner for 3 weeks. No alcohol had been drunk for one week prior to the study. Blood was obtained in the morning of the first and last day. Hematocrit (Hct), plasma (PV) and whole blood viscosity (WBV) (Hevimet 40 capillary viscometer), red blood cell (RBC) aggregation (Myrenne and LORCA aggregometer) and deformability (LORCA ektacytometer) were measured and Hct/WBV ratio was calculated to determine oxygen carrying capacity. Hct was adjusted to 40%. Hct and PV were not affected. WBV remained unchanged in controls, but it considerably decreased in the red wine group compared to the 3-week control group, while Hct/WBV ratio became significantly higher in the red wine group compared to the control (p < 0.05). RBC aggregation significantly decreased in the red wine group and became significantly lower compared to the 3-week controls (p < 0.05). Red wine significantly increased RBC deformability (p < 0.05) at high shear stress. Our results show that moderate red wine consumption has beneficial effects on hemorheological parameters which may contribute to the French-paradox.


Assuntos
Consumo de Bebidas Alcoólicas/sangue , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/prevenção & controle , Vinho , Adolescente , Adulto , Viscosidade Sanguínea , Agregação Eritrocítica , Deformação Eritrocítica , Hematócrito , Hemorreologia , Humanos , Masculino , Adulto Jovem
11.
Clin Hemorheol Microcirc ; 56(3): 197-204, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23445629

RESUMO

Cardiovascular diseases (CVD) are the most frequent cause of death throughout the world. The coronary vessel system is a special part of the circulation since there is a continuous change in blood flow, perfusion pressure and shear rate during each cardiac cycle. It is also the place of the narrowest capillaries in the human body, therefore the role of rheological alterations may be of greater importance than in the other parts of the circulatory system. During the past decades, our group has investigated hemorheological parameters (HP) in over 1,000 patients diagnosed with various forms of ischemic heart disease (IHD). In one prospective study, we measured the HP of patients with acute coronary syndrome (ACS). On admission, all examined variables were significantly worse than those of control subjects. During the hospital phase, some of the HP showed further deterioration, and HP remained in the pathologic range during the follow-up period. In another study, we showed that HP are in close correlation with the severity of coronary artery disease. In patients treated with percutaneous coronary intervention, changes in HP were very similar to those observed in subjects with ACS. In a recent study, we analyzed HP in patients undergoing CABG surgery. Our data suggest a hemorheological advantage of off-pump surgery. In another study low Hct/WBV ratio can be regarded as a risk factor of cardiac death in IHD. Our data indicate that rheological parameters are significantly altered in patients with IHD: the extent of the alterations is in excellent correlation with the clinical severity of the disease. Our findings prove that HP play a critical role in the pathogenesis of myocardial ischemia. In recent in vitro and in vivo studies we have investigated the effects of red wine on hemorheological parameters. Our results show that moderate red wine consumption has beneficial effects on hemorheological parameters which may contribute to the French paradox.


Assuntos
Viscosidade Sanguínea/efeitos dos fármacos , Doenças Cardiovasculares/sangue , Hemorreologia/efeitos dos fármacos , Isquemia Miocárdica/sangue , Doenças Cardiovasculares/fisiopatologia , Feminino , Humanos , Masculino , Isquemia Miocárdica/fisiopatologia , Fatores de Risco
12.
Br J Pharmacol ; 170(4): 768-78, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23647096

RESUMO

BACKGROUND AND PURPOSE: At present there are no small molecule inhibitors that show strong selectivity for the Na(+) /Ca(2+) exchanger (NCX). Hence, we studied the electrophysiological effects of acute administration of ORM-10103, a new NCX inhibitor, on the NCX and L-type Ca(2+) currents and on the formation of early and delayed afterdepolarizations. EXPERIMENTAL APPROACH: Ion currents were recorded by using a voltage clamp technique in canine single ventricular cells, and action potentials were obtained from canine and guinea pig ventricular preparations with the use of microelectrodes. KEY RESULTS: ORM-10103 significantly reduced both the inward and outward NCX currents. Even at a high concentration (10 µM), ORM-10103 did not significantly change the L-type Ca(2+) current or the maximum rate of depolarization (dV/dtmax ), indicative of the fast inward Na(+) current. At 10 µM ORM-10103 did not affect the amplitude or the dV/dtmax of the slow response action potentials recorded from guinea pig papillary muscles, which suggests it had no effect on the L-type Ca(2+) current. ORM-10103 did not influence the Na(+) /K(+) pump or the main K(+) currents of canine ventricular myocytes, except the rapid delayed rectifier K(+) current, which was slightly diminished by the drug at 3 µM. The amplitudes of pharmacologically- induced early and delayed afterdepolarizations were significantly decreased by ORM-10103 (3 and 10 µM) in a concentration-dependent manner. CONCLUSIONS AND IMPLICATIONS: ORM-10103 is a selective inhibitor of the NCX current and can abolish triggered arrhythmias. Hence, it has the potential to be used to prevent arrhythmogenic events.


Assuntos
Antiarrítmicos/farmacologia , Benzopiranos/farmacologia , Ventrículos do Coração/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Piridinas/farmacologia , Trocador de Sódio e Cálcio/antagonistas & inibidores , Potenciais de Ação , Animais , Canais de Cálcio Tipo L/efeitos dos fármacos , Canais de Cálcio Tipo L/metabolismo , Sinalização do Cálcio/efeitos dos fármacos , Cães , Relação Dose-Resposta a Droga , Feminino , Cobaias , Ventrículos do Coração/metabolismo , Masculino , Miócitos Cardíacos/metabolismo , Músculos Papilares/efeitos dos fármacos , Músculos Papilares/metabolismo , Potássio/metabolismo , Ramos Subendocárdicos/efeitos dos fármacos , Ramos Subendocárdicos/metabolismo , Sódio/metabolismo , Trocador de Sódio e Cálcio/metabolismo , Fatores de Tempo
13.
Clin Hemorheol Microcirc ; 53(1-2): 81-96, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22954637

RESUMO

Platelets play an important role both in normal hemostasis and in pathological thrombus formation. Several large-scale clinical studies have proved that the inhibition of platelet aggregation results in a significant decrease in mortality and morbidity of ischemic atherothrombotic events, thus antiplatelet therapy became a key pharmacological method in prevention and treatment of such cardiovascular, cerebrovascular and peripheral arterial diseases. The present paper aims to give a brief overview of the most important antiplatelet drugs, their mechanism of action and their recommended usage in cardiovascular diseases. We also discuss possible methods to monitor the effectiveness of therapy and possible causes of therapeutic failure.


Assuntos
Doenças Cardiovasculares/tratamento farmacológico , Inibidores da Agregação Plaquetária/uso terapêutico , Síndrome Coronariana Aguda/tratamento farmacológico , Anti-Inflamatórios não Esteroides/uso terapêutico , Plaquetas/efeitos dos fármacos , Doenças Cardiovasculares/prevenção & controle , Clopidogrel , Inibidores de Ciclo-Oxigenase/uso terapêutico , Humanos , Inibidores de Fosfodiesterase/uso terapêutico , Agregação Plaquetária/efeitos dos fármacos , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores , Ticlopidina/análogos & derivados , Ticlopidina/uso terapêutico
14.
Basic Clin Pharmacol Toxicol ; 110(3): 269-74, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21952040

RESUMO

Radial artery frequently develops spasm and requires vasodilator therapy during coronary artery bypass graft surgery (CABG). Levosimendan was recently shown to oppose 5-hydroxytryptamine-induced contraction of radial artery (RA) grafts. The aim of the present study was to explore whether levosimendan retains its vasodilatory capacity following in vitro pre-incubation of RA segments with the inodilator. A possible cumulative effect of the drug in human platelets was also studied. Human isolated RA segments were pre-incubated in 0.16 µmol/L levosimendan containing solution or in 0.9% NaCl, Bretschneider, 5% albumin and a 5% human serum protein solution (Biseko) as controls for 45 min. Contractions were induced by three consecutive administrations of 5-hydroxytryptamine (0.31 µM) 45, 90 and 120 min. after exchanging the pre-incubation solutions with Krebs-Henseleit solution, uniformly. Receptor-independent contractions (KCl, 80 mmol/L), endothelium-dependent (acetylcholine, 1 µmol/L) and independent relaxations (papaverine, 100 µmol/L) were also investigated. Washed human platelets were pre-incubated with levosimendan (0.06 µmol/L) for 2 or 15 min. and aggregated with thrombin (0.1 IU/mL). Contractions of RA grafts induced by 5-hydroxytryptamine were significantly smaller 45 min. and 90 min. after the replacement of levosimendan with Krebs-Henseleit solution. Biseko solution also decreased the contraction of the graft at 45 min. Contractions did not change in time following the pre-incubations of radial arteries with 0.9% NaCl, Bretschneider and 5% albumin solutions. The grafts remained intact as assessed by their maximum contractions and endothelium-dependent and endothelium-independent relaxations at the end of the investigations. Platelets revealed larger anti-aggregatory effect to levosimendan following the enhancement of the incubation time. Results indicate that the antispasmodic and anti-aggregatory effects of levosimendan cumulate in the vascular tissue and in platelets. The storage of RA with the inodilator before implantation may help to prevent the intraoperative spasm of the graft and also thrombotic occlusion during CABG surgery.


Assuntos
Hidrazonas/farmacologia , Parassimpatolíticos/farmacologia , Piridazinas/farmacologia , Artéria Radial/efeitos dos fármacos , Vasodilatadores/farmacologia , Feminino , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/farmacologia , Artéria Radial/metabolismo , Simendana , Fatores de Tempo , Vasoconstrição/efeitos dos fármacos
15.
Curr Med Chem ; 18(24): 3662-74, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21774761

RESUMO

The pacemaker channel isoforms are encoded by the hyperpolarization-activated and cyclic nucleotide-gated (HCN) gene family and are responsible for diverse cellular functions including regulation of spontaneous activity in sino-atrial node cells and control of excitability in different types of neurons. Four channel isoforms exist (HCN1-HCN4). The hyperpolarization-activated cardiac pacemaker current (I(f)) has an important role in the generation of the diastolic depolarization in the sino-atrial node, while its neuronal equivalent (I(h)) is an important contributor to determination of resting membrane potential, and plays an important role in neuronal functions such as synaptic transmission, motor learning and generation of thalamic rhythms. Ivabradine is a novel, heart rate-lowering drug which inhibits the pacemaker (I(f)) current in the heart with high selectivity and with minimal effect on haemodynamic parameters. Ivabradine is beneficial in patients with chronic stable angina pectoris equally to beta receptor blocker and calcium channel antagonist drugs. There is increasing interest to apply this drug in other fields of cardiology such as heart failure, myocardial infarction, cardiac arrhyhtmias. Heart rate reduction might improve clinical outcomes in heart failure. HCN upregulation presumably contributes to increased (I(f)) and may play a role in ventricular and atrial arrhythmogenesis in heart failure. In the nervous system the HCN channels received attention in the research areas of neuropathic pain, epilepsy and understanding the mechanism of action of volatile anaesthetics. This article delineates that the pharmacological modulation of cardiac and neuronal HCN channels can serve current or future drug therapy and introduces some recently investigated HCN channel inhibitor compounds being potential candidates for development.


Assuntos
Canais de Cátion Regulados por Nucleotídeos Cíclicos/antagonistas & inibidores , Benzazepinas/química , Benzazepinas/farmacologia , Benzazepinas/uso terapêutico , Fármacos Cardiovasculares/química , Fármacos Cardiovasculares/farmacologia , Fármacos Cardiovasculares/uso terapêutico , Ensaios Clínicos como Assunto , Canais de Cátion Regulados por Nucleotídeos Cíclicos/metabolismo , Cardiopatias/tratamento farmacológico , Cardiopatias/metabolismo , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Humanos , Ivabradina , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/metabolismo , Nó Sinoatrial/efeitos dos fármacos , Nó Sinoatrial/metabolismo
16.
Br J Pharmacol ; 164(1): 93-105, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21410683

RESUMO

BACKGROUND AND PURPOSE: The contribution of the transient outward potassium current (I(to)) to ventricular repolarization is controversial as it depends on the experimental conditions, the region of myocardium and the species studied. The aim of the present study was therefore to characterize I(to) and estimate its contribution to repolarization reserve in canine ventricular myocardium. EXPERIMENTAL APPROACH: Ion currents were recorded using conventional whole-cell voltage clamp and action potential voltage clamp techniques in canine isolated ventricular cells. Action potentials were recorded from canine ventricular preparations using microelectrodes. The contribution of I(to) to repolarization was studied using 100 µM chromanol 293B in the presence of 0.5 µM HMR 1556, which fully blocks I(Ks). KEY RESULTS: The high concentration of chromanol 293B used effectively suppressed I(to) without affecting other repolarizing K(+) currents (I(K1), I(Kr), I(p)). Action potential clamp experiments revealed a slowly inactivating and a 'late' chromanol-sensitive current component occurring during the action potential plateau. Action potentials were significantly lengthened by chromanol 293B in the presence of HMR 1556. This lengthening effect induced by I(to) inhibition was found to be reverse rate-dependent. It was significantly augmented after additional attenuation of repolarization reserve by 0.1 µM dofetilide and this caused the occurrence of early afterdepolarizations. The results were confirmed by computer simulation. CONCLUSIONS AND IMPLICATIONS: The results indicate that I(to) is involved in regulating repolarization in canine ventricular myocardium and that it contributes significantly to the repolarization reserve. Therefore, blockade of I(to) may enhance pro-arrhythmic risk.


Assuntos
Sistema de Condução Cardíaco/metabolismo , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Canais de Potássio/metabolismo , Potenciais de Ação/efeitos dos fármacos , Animais , Cromanos/farmacologia , Cães , Feminino , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/metabolismo , Masculino , Miocárdio/citologia , Miócitos Cardíacos/efeitos dos fármacos , Técnicas de Patch-Clamp , Fenetilaminas/farmacologia , Bloqueadores dos Canais de Potássio/farmacologia , Sulfonamidas/farmacologia , Função Ventricular/efeitos dos fármacos
17.
Clin Hemorheol Microcirc ; 49(1-4): 331-46, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22214705

RESUMO

Conditions during coronary artery bypass grafting (CABG) performed on beating heart (off-pump) are more physiological than using extracorporeal perfusion (on-pump). The present study aims to examine the hemorheological aspects of the two techniques. Blood samples were taken from patients undergoing on-pump (n = 25) and off-pump (n = 22) CABG, upon arrival to the operating theatre, after 20 and 40 minutes during the operation, after closing the thorax, on the 1st and 2nd postoperative days, and during the 2nd and 6th month control check-ups. Hematocrit (Hct), plasma and whole blood viscosity (PV, WBV; Hevimet 40 capillary viscometer), red blood cell (RBC) aggregation (Myrenne RBC aggregometer, LORCA) and deformability (LORCA, Carat FT-1 filtrometer), and platelet aggregation (Carat TX4 aggregometer) were determined. The morphology of red blood cells was investigated by scanning electron microscopy (SEM). Hct, PV, WBV and RBC aggregation decreased significantly during the early phase of the surgery, they started to recover during the postoperative period, and reached the baseline values by the 2nd and 6th month control check-ups. These parameters were significantly lower in samples taken after 20 and 40 minutes in the on-pump group. SEM showed rather damaged and malformed cells in case of on-pump surgery. Ektacytometry showed no significant difference, but RBC deformability was impaired during on-pump surgery when measured by filtrometry. The decrease in platelet aggregation was more pronounced by the end of surgery in case of on-pump technique. During CABG rheological parameters change less when using the off-pump method, and mechanical damage of RBCs are also smaller. The off-pump technique seems to be favorable from a hemorhelogical point of view.


Assuntos
Ponte Cardiopulmonar , Ponte de Artéria Coronária , Hemorreologia , Idoso , Comorbidade , Ponte de Artéria Coronária sem Circulação Extracorpórea , Procedimentos Cirúrgicos Eletivos , Eritrócitos/ultraestrutura , Feminino , Máquina Coração-Pulmão , Humanos , Masculino , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade
18.
Pain ; 151(3): 732-736, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20851521

RESUMO

Sensory neuropathy (HIV-SN) is a common cause of pain in HIV-infected people. Establishing a diagnosis of HIV-SN is important, especially when contemplating opioid use in high-risk populations. However physical findings of HIV-SN may be subtle, and sensitive diagnostic tools require specialized expertise. We investigated the association between self-report of distal neuropathic pain and/or paresthesias (DNPP) and objective signs of HIV-SN. Data were obtained from the Central Nervous System HIV Antiretroviral Therapy Effects Research (CHARTER) study. Out of 237 participants, 101 (43%) reported DNPP. Signs of HIV-SN were measured by a modified Total Neuropathy Score (TNS), composed of six objective sensory subscores (pin sensibility, vibration sensibility, deep tendon reflexes, quantitative sensory testing for cooling and vibration, and sural sensory amplitude). Self-report of DNPP was associated with all six TNS items in univariate analysis and with four TNS items in multivariate analysis. The sensitivity and specificity of self-report of DNPP in detecting the presence of a sensory abnormality were 52% and 92%, respectively with a PPV of 96% and a NPV of 34%. Increasing intensity of pain measured on a visual analog scale was associated with increasing severity of sensory abnormality. In summary, our results suggest that HIV-infected patients reporting symptoms consistent with HIV-SN, such as tingling, pins and needles, or aching or stabbing pain in the distal lower extremities, usually have objective evidence of HIV-SN on neurologic examination or with neurophysiologic testing. This finding holds true regardless of demographic factors, depression or substance use history.


Assuntos
Infecções por HIV/complicações , Neuralgia/complicações , Doenças do Sistema Nervoso Periférico/complicações , Polineuropatias/complicações , Adulto , Feminino , Humanos , Modelos Lineares , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Neuralgia/diagnóstico , Neuralgia/fisiopatologia , Medição da Dor , Doenças do Sistema Nervoso Periférico/diagnóstico , Doenças do Sistema Nervoso Periférico/fisiopatologia , Polineuropatias/diagnóstico , Polineuropatias/fisiopatologia , Células Receptoras Sensoriais
19.
J Inherit Metab Dis ; 31 Suppl 2: S461-7, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19107570

RESUMO

Leigh syndrome is a neurodegenerative disorder of infancy or childhood generally due to mutations in nuclear or mitochondrial genes involved in mitochondrial energy metabolism. We performed linkage analysis in an Ashkenazi Jewish (AJ) family without consanguinity with three affected children. Linkage to microsatellite markers D5S1969 and D5S407 led to evaluation of the complex I gene NDUFS4, in which we identified a novel homozygous c.462delA mutation that disrupts the reading frame. The resulting protein lacks a cAMP-dependent protein kinase phosphorylation site required for activation of mitochondrial respiratory chain complex I. In a random sample of 5000 healthy AJ individuals, the carrier frequency of the NDUFS4 mutation c.462delA was 1 in 1000, suggesting that it should be considered in all AJ patients with Leigh syndrome.


Assuntos
Judeus/genética , Doença de Leigh/genética , Mutação , NADH Desidrogenase/genética , Adulto , Sequência de Bases , Pré-Escolar , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Análise Mutacional de DNA , Complexo I de Transporte de Elétrons/metabolismo , Evolução Fatal , Feminino , Frequência do Gene , Ligação Genética , Predisposição Genética para Doença , Haplótipos , Hereditariedade , Homozigoto , Humanos , Lactente , Doença de Leigh/complicações , Doença de Leigh/diagnóstico , Doença de Leigh/enzimologia , Doença de Leigh/etnologia , Masculino , Repetições de Microssatélites , Dados de Sequência Molecular , Linhagem , Fenótipo , Fosforilação , Gravidez , Processamento de Proteína Pós-Traducional
20.
Dig Liver Dis ; 40(11): 867-73, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18499543

RESUMO

BACKGROUND: North American and European genome-wide association scans have identified ATG16L1 and IL23R as novel inflammatory bowel disease (IBD) susceptibility genes and subsequent reports confirmed these findings in large independent populations. The aims of this study were to investigate the association and examine genotype-phenotype relationships in a Hungarian IBD cohort. METHODS: 415 unrelated IBD patients (CD: 266, age: 35.2+/-12.1 years, duration: 8.7+/-7.5 years and UC: 149, age: 44.4+/-15.4 years, duration: 10.7+/-8.9 years) and 149 healthy subjects were investigated. IL23R Arg381Gln (R381Q, rs11209026) and ATG16L1 Thr300Ala (T300A, rs2241880) polymorphisms were tested using LightCycler allele discrimination method. Detailed clinical phenotypes were determined by reviewing the medical charts. RESULTS: The association between IL23R rs11209026, ATG16L1 rs2241880 and CD was confirmed (OR(IL23R381Q): 0.38, 95% CI: 0.16-0.87; OR(ATG16L1300AA): 1.86, 95% CI: 1.04-3.40). No difference was found between patients with UC and either controls or CD. In CD, IL23R 381Gln heterozygosity was associated with inflammatory disease (70% vs. 34%, p=0.037), while disease restricted to the colon was more prevalent in patients with the ATG16L1 300Ala/Ala homozygosity (33.3% vs. 21.1%, p=0.036). In addition, carriage of the variant alleles did not predict response to steroids, infliximab or need for surgery. CONCLUSIONS: We confirmed that ATG16L1 and IL23R are susceptibility loci for CD in Hungarian CD patients. Further studies are needed to confirm the reported phenotype-genotype associations found in this study.


Assuntos
Proteínas de Transporte/genética , Colite Ulcerativa/genética , Doença de Crohn/genética , Predisposição Genética para Doença/epidemiologia , Receptores de Interleucina/genética , Adulto , Distribuição por Idade , Proteínas Relacionadas à Autofagia , Estudos de Casos e Controles , Colite Ulcerativa/diagnóstico , Colite Ulcerativa/etnologia , Intervalos de Confiança , Doença de Crohn/diagnóstico , Doença de Crohn/etnologia , Feminino , Regulação da Expressão Gênica , Genótipo , Humanos , Hungria/epidemiologia , Incidência , Doenças Inflamatórias Intestinais/etnologia , Doenças Inflamatórias Intestinais/genética , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Medição de Risco , Distribuição por Sexo , População Branca/estatística & dados numéricos
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