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1.
Trials ; 21(1): 192, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32066489

RESUMO

BACKGROUND: Ticagrelor is a reversibly binding, direct-acting, oral, P2Y12 antagonist used for the prevention of atherothrombotic events in patients with coronary artery disease (CAD). Ticagrelor blocks adenosine reuptake through the inhibition of equilibrative nucleoside transporter 1 (ENT-1) on erythrocytes and platelets, thereby facilitating adenosine-induced physiological responses such as an increase in coronary blood flow velocity. Meanwhile, adenosine plays an important role in triggering ischemic preconditioning through the activation of the A1 receptor. Therefore, an increase in ticagrelor-enhanced adenosine bioavailability may confer beneficial effects through mechanisms related to preconditioning activation and improvement of coronary microvascular dysfunction. METHODS: To determine whether ticagrelor can trigger ischemic preconditioning and influence microvascular function, we designed this prospective, open-label, pilot study that enrolled patients with stable multivessel CAD requiring staged, fractional flow reserve (FFR)-guided percutaneous coronary intervention (PCI). Participants will be randomized in 1:1 ratios either to ticagrelor (loading dose (LD) 180 mg, maintenance dose (MD) 90 mg bid) or to clopidogrel (LD 600 mg, MD 75 mg) from 3 to 1 days before the scheduled PCI. The PCI operators will be blinded to the randomization arm. The primary endpoint is the delta (difference) between ST segment elevations (in millimeters, mm) as assessed by intracoronary electrocardiogram (ECG) during the two-step sequential coronary balloon inflation in the culprit vessel. Secondary endpoints are 1) changes in coronary flow reserve (CFR), index of microvascular resistance (IMR), and FFR measured in the culprit vessel and reference vessel at the end of PCI, and 2) angina score during inflations. This study started in 2018 with the aim of enrolling 100 patients. Based on the rate of negative FFR up to 30% and a drop-out rate up to 10%, we expect to detect an absolute difference of 4 mm among the study arms in the mean change of ST elevation following repeated balloon inflations. All study procedures were reviewed and approved by the Ethical Committee of the Catholic University of Sacred Heart. DISCUSSION: Ticagrelor might improve ischemia tolerance and microvascular function compared to clopidogrel, and these effects might translate to better long-term clinical outcomes. TRIAL REGISTRATION: EudraCT No. 2016-004746-28. No. NCT02701140.  TRIAL STATUS: Information provided in this manuscript refers to the definitive version (n. 3.0) of the study protocol, dated 31 October 2017, and includes all protocol amendments. Recruitment started on 18 September 2018 and is currently ongoing. The enrollment is expected to be completed by the end of 2019. TRIAL SPONSOR: Fondazione Policlinico Universitario A. Gemelli - Roma, Polo di Scienze Cardiovascolari e Toraciche, Largo Agostino Gemelli 8, 00168 Rome, Italy.


Assuntos
Doença da Artéria Coronariana/cirurgia , Precondicionamento Isquêmico Miocárdico/métodos , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Intervenção Coronária Percutânea/efeitos adversos , Ticagrelor/administração & dosagem , Adolescente , Adulto , Idoso , Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Clopidogrel/administração & dosagem , Vasos Coronários/efeitos dos fármacos , Feminino , Reserva Fracionada de Fluxo Miocárdico/efeitos dos fármacos , Humanos , Masculino , Microvasos/efeitos dos fármacos , Pessoa de Meia-Idade , Traumatismo por Reperfusão Miocárdica/etiologia , Projetos Piloto , Cuidados Pré-Operatórios/métodos , Antagonistas do Receptor Purinérgico P2Y/administração & dosagem , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento , Resistência Vascular/efeitos dos fármacos , Adulto Jovem
2.
AAPS PharmSciTech ; 21(2): 54, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31907712

RESUMO

Cervical cancer is associated with the human papilloma virus (HPV) and nowadays is the fourth most frequent cancer among women. One of the treatments for this disease is based on the application of imiquimod. In this study, we postulated that the use of imiquimod in nanoemulsion results in a better antitumoral effect than the drug administered in its nonencapsulated form for the treatment of cervical cancer. Permeability studies using vaginal mucosa, as membrane, and in vitro studies involving cervical cancer cells (viability, clonogenic assay, and cell death analysis) were performed. We showed that low amount of encapsulated imiquimod permeated the vaginal mucosa. However, a higher percentage of cells died after the treatment with low amount (3.0 µmol L-1) of the formulation compared to the free drug. In addition, the innovative formulation presented a combinatory mechanism of cell death involving autophagy and apoptosis. Our results demonstrate that the imiquimod-loaded nanoemulsioncan be an alternative product for the treatment of cervical cancer validating the hypothesis.


Assuntos
Imiquimode/administração & dosagem , Papillomaviridae/efeitos dos fármacos , Neoplasias do Colo do Útero/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Composição de Medicamentos , Emulsões , Feminino , Humanos , Nanopartículas , Suínos , Neoplasias do Colo do Útero/virologia
3.
Eur J Pharm Biopharm ; 136: 9-17, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30630060

RESUMO

This paper proposes the development of imiquimod-loaded polymeric nanocapsules formulation for the treatment of cervical cancer. The mechanism of death involved in the reduction of the cell viability as well as the production of an inflammation marker (IL-6) after the treatment in cell line SiHa have been evaluated. The formulation has significantly decreased the viability of the cells in a time-dependent manner, after 24, 48 and 72 h. Additionally, results showed a cellular decrease of almost 80% of the cells after 72 h of treatment. The formulation induced death by apoptosis, necrosis, autophagy, and increased the percentage of SubG1subpopulation of SiHa cells after 72 h. After the same time-interval, the formulation significantly prevented the appearance of colonies, showing effectiveness against SiHa. Finally, the formulation stimulated SiHa cells to release IL-6. These findings open new possibilities for the development of aqueous nanosuspension containing imiquimod as a novel strategy for the treatment of cervical cancer.


Assuntos
Antineoplásicos/administração & dosagem , Citotoxinas/administração & dosagem , Portadores de Fármacos/administração & dosagem , Imiquimode/administração & dosagem , Nanocápsulas/administração & dosagem , Neoplasias do Colo do Útero , Antineoplásicos/metabolismo , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Citotoxinas/metabolismo , Portadores de Fármacos/metabolismo , Feminino , Humanos , Imiquimode/metabolismo , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/metabolismo
4.
Biomed Pharmacother ; 94: 10-20, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28750355

RESUMO

Doxazosin has been evaluated for the treatment of several types of cancer. Here, the antitumor effect of the nanoencapsulated form of doxazosin was evaluated in an in vitro model of breast cancer (MCF7 cell line). Doxazosin-loaded polymeric nanocapsules (DXZ-NC) were produced by interfacial deposition of preformed polymer with homogeneous aspect, spherical shape, mean diameter of about 130nm, positive zeta potential (+5mV), and encapsulation efficiency close to 35%. The Alamar Blue® assay and cell counting were carried out to assess cell viability and cell number, respectively. Mechanism of death was evaluated by Annexin/Propidium Iodide staining, while the long-term response was assessed using the clonogenic assay. Nuclear morphometric analysis was investigated using the NMA technique. A significant decrease in cell viability and clonogenicity was observed after the treatment with DXZ-NC when compared to the non-encapsulated drug. All treatments induced apoptosis as the main mechanism of toxicity. In conclusion, the nanoencapsulation of doxazosin improved its in vitro effects in MCF7 cells, without changing the mechanism of cell death underlying its toxicity. This approach was fundamental to reduce the long-term in vitro ability of the remaining tumor cells to form new colonies after the treatment, potentially reducing the risk of tumor recurrence.


Assuntos
Neoplasias da Mama/patologia , Doxazossina/farmacologia , Nanocápsulas/química , Contagem de Células , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Clonais , Liberação Controlada de Fármacos , Feminino , Humanos , Células MCF-7 , Nanocápsulas/ultraestrutura , Tamanho da Partícula
5.
QJM ; 106(2): 105-15, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23097390

RESUMO

Until a few years ago, the mainstay of anti-platelet therapy in patients with acute coronary syndrome (ACS) was the combination of aspirin and clopidogrel, a P2Y12 receptor inhibitor. However, current clinical practice has now changed with the introduction of ticagrelor, a more potent cardiovascular drug than clopidogrel, without the limitations related to clopidogrel therapy. In this review, we provide a critical overview of ticagrelor in ACS, highlight the results with ticagrelor in several subgroups of patients and discuss the future trials.


Assuntos
Síndrome Coronariana Aguda/tratamento farmacológico , Adenosina/análogos & derivados , Inibidores da Agregação Plaquetária/uso terapêutico , Antagonistas do Receptor Purinérgico P2/uso terapêutico , Síndrome Coronariana Aguda/fisiopatologia , Adenosina/administração & dosagem , Adenosina/farmacologia , Adenosina/uso terapêutico , Aspirina/uso terapêutico , Clopidogrel , Método Duplo-Cego , Feminino , Humanos , Masculino , Antagonistas do Receptor Purinérgico P2/administração & dosagem , Antagonistas do Receptor Purinérgico P2/farmacologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Medição de Risco , Ticagrelor , Ticlopidina/análogos & derivados , Ticlopidina/uso terapêutico , Resultado do Tratamento
6.
Biochim Biophys Acta ; 1770(8): 1259-65, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17574764

RESUMO

In this study, we evaluated the NTPDases and ecto-5'-nucleotidase (CD73) expression profiles and the pattern of adenine nucleotide hydrolysis in rats submitted to the Walker 256 tumor model, 6, 10 and 15 days after the subcutaneous inoculation. Using RT-PCR analysis, we identified mRNA for all of the members of the ecto-nucleoside triphosphate diphosphohydrolase family investigated and a 5'-nucleotidase. By quantitative real-time PCR, Entpd1 (Cd39) and Entpd2 (Cd39L1) and CD73 were identified as the dominant genes expressed by the Walker 256 tumor, at all times studied. Extracellular adenine nucleotide hydrolysis by the Walker 256 tumor was estimated by HPLC analysis. Rapid hydrolysis of extracellular ATP by the tumor cells was observed, leading to the formation of adenosine and inosine in cells obtained from solid tumors at 6 and 10 days after inoculation. Cells obtained from solid tumors at 15 days of growth presented high levels of AMP and presented adenosine as a final product after 90 min of incubation. Results demonstrate that the presence of NTPDases and 5'-nucleotidase enzymes in Walker 256 tumor cells may be important for regulation of the extracellular adenine nucleotides/adenine nucleoside ratio, therefore leading to tumor growth.


Assuntos
5'-Nucleotidase/metabolismo , Adenosina Trifosfatases/metabolismo , Trifosfato de Adenosina/metabolismo , Antígenos CD/metabolismo , Apirase/metabolismo , Carcinoma 256 de Walker/enzimologia , Animais , Linhagem Celular Tumoral , Masculino , Ratos , Ratos Wistar
7.
Circulation ; 103(18): 2236-41, 2001 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-11342470

RESUMO

BACKGROUND: C-reactive protein (CRP) plasma levels have been associated with short- and long-term occurrence of coronary events. We investigated whether circulating inflammatory cell responsiveness to low-grade stimuli could contribute to the reported association between CRP and coronary events. METHODS AND RESULTS: We studied 32 patients with unstable angina who were followed for 24 months and were free of symptoms for 6 months (group 1): 19 patients had persistently high CRP levels (>0.3 mg/dL) (group 1A); 13 patients had normal CRP levels (group 1B). During the follow-up, 12 (63%) group 1A but no group 1B patients developed an infarction or recurrence of unstable angina (P<0.001). Eighteen patients with chronic stable angina (group 2) and 18 healthy subjects (group 3) were studied as controls. Interleukin (IL)-6 production (median, range) by peripheral blood mononuclear cells after 4 hours of in vitro stimulation with 1 ng/mL lipopolysaccharide (LPS) was significantly higher in group 1A (4526 pg/mL, 3042 to 10 583 pg/mL) than in group 1B (1752 pg/mL, 75 to 3981 pg/mL), group 2 (707 pg/mL, 41 to 3275 pg/mL), and group 3 (488 pg/mL, 92 to 3503 pg/mL) (all P<0.001). No significant differences were observed among the other groups. IL-6 production after LPS-challenge was correlated with baseline CRP levels (r=0.42, P=0.005). CONCLUSIONS: Mononuclear cells of patients with recurrent phases of instability exhibit an enhanced production of IL-6 in response to low-dose of LPS, correlated with baseline CRP levels, 6 months after the last acute event. This persisting enhanced acute-phase responsiveness may help explain the association between CRP and acute coronary events.


Assuntos
Angina Instável/diagnóstico , Angina Instável/imunologia , Lipopolissacarídeos/farmacologia , Monócitos/efeitos dos fármacos , Monócitos/imunologia , Angina Instável/metabolismo , Proteína C-Reativa/metabolismo , Proteína C-Reativa/farmacologia , Separação Celular , Doença Crônica , Sinergismo Farmacológico , Feminino , Seguimentos , Humanos , Interleucina-6/biossíntese , Interleucina-6/sangue , Masculino , Pessoa de Meia-Idade , Monócitos/metabolismo , Valor Preditivo dos Testes , Estudos Prospectivos , Recidiva
8.
Int J Biochem Cell Biol ; 32(1): 105-13, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10661899

RESUMO

We have tested several chemical modifiers to investigate which amino acid residues, present in the primary structure of the ecto-apyrase, could be involved in catalysis. Synaptosomes from cerebral cortex of rats were prepared and the ATP diphosphohydrolase activity was assayed in absence or the presence of the modifiers. Percentages of residual activity for ATPase and ADPase obtained when the following reagents were tested, are respectively: phenylglyoxal (an arginine group modifier) 17 and 30%; Woodward's reagent (a carboxylic group modifier) 33 and 23%; Koshland's reagent (a tryptophan group modifier) 10 and 12%; maleic anhidride (an amino group modifier) 11 and 25% and carbodiimide reagent (a carboxylic group modifier) 56 and 72%. Otherwise, PMSF, a seryl protein modifier and DTNB, a SH-group modifier did not affect either ATPase or ADPase activity. Inhibitions observed after treatment with phenylglyoxal and Woodward's reagent were significantly prevented when the synaptosomal fraction was preincubated with ATP and ADP, indicating that the arginine and the side chain of glutamate or aspartate (carboxyl groups) participate in the structure of the active site. This interpretation was confirmed by using GTP and GDP, two other apyrase substrates. Phenylglyoxal and Woodward's reagent also inhibited the GTPase and GDPase activities and this inhibition was prevented by preincubation with these substrates.


Assuntos
Adenosina Trifosfatases/metabolismo , Encéfalo/enzimologia , 2-Hidroxi-5-nitrobenzil Brometo/farmacologia , Adenosina Trifosfatases/antagonistas & inibidores , Animais , Antígenos CD , Apirase/metabolismo , Carbodi-Imidas/farmacologia , Inibidores Enzimáticos/farmacologia , Feminino , Guanosina Difosfato/metabolismo , Guanosina Trifosfato/metabolismo , Isoxazóis/farmacologia , Anidridos Maleicos/farmacologia , Fenilglioxal/farmacologia , Ratos , Sinaptossomos/enzimologia
9.
J Am Coll Cardiol ; 34(6): 1696-703, 1999 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-10577559

RESUMO

OBJECTIVES: We assessed the extent and the time course of the acute phase response following myocardial cell necrosis and its relationship with the presence of preinfarction unstable angina (UA). BACKGROUND: Elevated levels of acute phase proteins have been reported in patients with UA and in patients with acute myocardial infarction (MI). METHODS: C-Reactive Protein (CRP), serum amyloid A protein (SAA) and interleukin-6 (IL-6) were measured in 36 patients with MI admitted within 3 h from symptoms onset. All patients had normal levels of creatine kinase and of troponin T on admission, rising above diagnostic levels within 6 to 12 h. Blood samples for CRP, SAA and IL-6 measurements were taken on admission, at 6, 24, 48, 72 h and at discharge. RESULTS: Twenty of the 36 patients studied presented an unheralded MI (Group 1); the remaining 16 patients had symptoms of unstable angina in the preceding 7 days (Group 2). Group 2 patients have much higher levels of CRP and SAA on admission (median values 8.8 vs. 3 mg/L and 28 vs. 3.4 mg/L, respectively, all p<0.001). Following the necrotic insult, despite similar infarct size and clinical signs of reperfusion, Group 2 patients had strikingly higher peaks of IL-6 (median values 85.2 vs. 19 pg/ml, p<0.05), CRP (50 vs. 31.4 mg/L, p<0.05) and SAA (228 vs. 45 mg/L, p<0.001). CONCLUSIONS: Our data demonstrated that the acute phase response is greatly enhanced in patients with preinfarction UA compared with those presenting with an unheralded MI. The significant differences in acute phase response observed in these two clinical presentations of MI indicate a major difference in their underlying pathogenetic components.


Assuntos
Reação de Fase Aguda/patologia , Angina Instável/patologia , Reação de Fase Aguda/sangue , Reação de Fase Aguda/etiologia , Idoso , Angina Instável/sangue , Proteína C-Reativa/análise , Creatina Quinase/sangue , Feminino , Humanos , Interleucina-6/análise , Masculino , Pessoa de Meia-Idade , Miocárdio/patologia , Necrose , Proteína Amiloide A Sérica/análise , Troponina T/sangue
10.
Circulation ; 98(22): 2370-6, 1998 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-9832480

RESUMO

BACKGROUND: Systemic markers of inflammation have been found in unstable angina. Disruption of culprit coronary stenoses may cause a greater inflammatory response in patients with unstable than those with stable angina. We assessed the time course of C-reactive protein (CRP), serum amyloid A protein (SAA), and interleukin-6 (IL-6) after single-vessel PTCA in 30 patients with stable and 56 patients with unstable angina (protocol A). We also studied 12 patients with stable and 15 with unstable angina after diagnostic coronary angiography (protocol B). METHODS AND RESULTS: Peripheral blood samples were taken before and 6, 24, 48, and 72 hours after PTCA or angiography. In protocol A, baseline CRP, SAA, and IL-6 levels were normal in 87% of stable and 29% of unstable patients. After PTCA, CRP, SAA, and IL-6 did not change in stable patients and unstable patients with normal baseline levels but increased in unstable patients with raised baseline levels (all P<0.001). In protocol B, CRP, SAA, and IL-6 did not change in stable angina patients after angiography but increased in unstable angina patients (all P<0.05). Baseline CRP and SAA levels correlated with their peak values after PTCA and angiography (all P<0.001). CONCLUSIONS: Our data suggest that plaque rupture per se is not the main cause of the acute-phase protein increase in unstable angina and that increased baseline levels of acute-phase proteins are a marker of the hyperresponsiveness of the inflammatory system even to small stimuli. Thus, an enhanced inflammatory response to nonspecific stimuli may be involved in the pathogenesis of unstable angina.


Assuntos
Reação de Fase Aguda/etiologia , Angina Instável/sangue , Angina Instável/terapia , Angioplastia Coronária com Balão/efeitos adversos , Proteínas de Fase Aguda/análise , Idoso , Angina Pectoris/sangue , Proteína C-Reativa/análise , Angiografia Coronária/efeitos adversos , Feminino , Humanos , Interleucina-6/sangue , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Proteína Amiloide A Sérica/análise
11.
Eur Heart J ; 18(4): 614-7, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9129891

RESUMO

BACKGROUND: In order to ascertain whether human adenosine-induced dilatation of epicardial arteries is direct or flow-mediated, we compared the effects of intracoronary adenosine infusion on epicardial coronary arteries with those produced by dipiridamole, a selective arteriolar vasodilator. METHODS AND RESULTS: In 24 patients with angiographically normal coronary arteries, coronary blood flow velocity was measured by a Doppler wire during intracoronary infusion of adenosine or dipyridamole, which is known to increase intramyocardial adenosine concentration. Coronary angiograms were obtained at baseline and immediately after the end of each infusion period; coronary diameters 5 mm distal to the wire tip were measured by computer-assisted quantitative coronary angiography. Peak coronary blood flow velocities during adenosine or dipyridamole infusions were similar (52.0 +/- 15.5 and 47.9 +/- 24.2 cm.s-1, P = ns). Coronary diameters immediately after adenosine and dipyridamole infusions were similar and both higher than that at baseline (2.80 +/- 0.63 and 2.86 +/- 0.64 vs 2.44 +/- 0.69 mm, P < 0.05). The absolute and percentage increases of coronary artery diameters in response to adenosine were highly correlated to coronary blood flow velocity (R = 0.622, intercept -0.10 +/- 0.14, P = 0.002 and R = 0.617, intercept -15.2 +/- 9.9, P = 0.001, respectively); similar correlations were found in response to dipyridamole (R = 0.708, intercept -0.44 +/- 0.19, P < 0.001 and R = 0.649, intercept -13.5 +/- 8.7, P < 0.001, respectively). Finally the absolute and percentage changes of coronary artery diameters caused by adenosine were highly correlated to those caused by dipyridamole (R = 0.840 P < 0.001 and R = 0.836, P < 0.001 respectively). CONCLUSIONS: A significant correlation exists between epicardial coronary vasodilation and coronary blood flow velocity during intracoronary adenosine infusion, thus suggesting that epicardial coronary vasodilation induced by adenosine is predominantly flow-mediated rather than direct. This conclusion is supported by the observation that similar findings were obtained using dipyridamole, which can only dilate epicardial coronary arteries indirectly, through the increase in coronary blood flow velocity caused by the inhibition of intramyocardial adenosine re-uptake.


Assuntos
Adenosina/farmacologia , Circulação Coronária/efeitos dos fármacos , Doença das Coronárias/fisiopatologia , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Velocidade do Fluxo Sanguíneo/fisiologia , Angiografia Coronária/efeitos dos fármacos , Circulação Coronária/fisiologia , Dipiridamol/farmacologia , Ecocardiografia Doppler/efeitos dos fármacos , Humanos , Processamento de Imagem Assistida por Computador , Vasodilatação/fisiologia
12.
Coron Artery Dis ; 6(6): 479-87, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7551269

RESUMO

BACKGROUND: Previous studies reported a reduced coronary blood flow reserve, assessed by the intravenous administration of dipyridamole, in patients with angina and normal coronary arteries, and early after successful coronary angioplasty, which suggests the presence of small coronary vessel dysfunction. This study aimed to establish whether the mechanisms of small coronary vessel disease in these two groups of patients are similar. METHODS: The effects of the intracoronary infusion of adenosine and dipyridamole (maximum dose 2.7 and 7.5 mg/min, respectively) on coronary blood flow velocity were assessed in 11 patients with angina and normal coronary arteries (group A) and in 12 patients immediately after successful coronary angioplasty (group B) using a 0.018" Doppler wire. RESULTS: Baseline coronary blood flow velocity was significantly higher in group B than group A (34 +/- 14 versus 19 +/- 8 cm/s; P = 0.001). In group A, coronary blood flow velocity was higher during adenosine than dipyridamole infusion (74 +/- 17 versus 58 +/- 21 cm/s; P < 0.001), whereas in group B velocities were similar (85 +/- 30 versus 78 +/- 32 cm/s; NS). CONCLUSIONS: In patients with angina and normal coronary arteries, a maximal dose of adenosine causes a greater coronary dilation than that of dipyridamole. Given that dipyridamole operates mainly through an inhibition of adenosine re-uptake, it can only dilate the arteriolar segments exposed to endogenous adenosine. Therefore, the lower response to dipyridamole than to exogenous adenosine observed in patients with angina and normal coronary arteries suggests an impairment of the pre-arterioles that are not influenced by endogenous adenosine, resulting in a limited flow-mediated dilation in response to arteriolar dilation. Such an impairment is not apparent immediately after successful coronary angioplasty, where the most obvious abnormality is an increase of baseline coronary blood flow velocity.


Assuntos
Angina Pectoris/fisiopatologia , Circulação Coronária/efeitos dos fármacos , Dipiridamol/farmacologia , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia , Adenosina/farmacologia , Angina Pectoris/tratamento farmacológico , Angina Pectoris/cirurgia , Angioplastia Coronária com Balão , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Dipiridamol/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional/efeitos dos fármacos , Vasodilatadores/uso terapêutico
13.
Cardiologia ; 38(12 Suppl 1): 169-79, 1993 Dec.
Artigo em Italiano | MEDLINE | ID: mdl-7912650

RESUMO

The treatment of microvascular angina (anginal pain resulting from myocardial ischemia due to dysfunction of small coronary arteries) is empiric and often ineffective at present. The poor knowledge of the pathophysiologic mechanisms responsible for the microvascular dysfunction and the possible heterogeneous nature of the disease limit the possibility of a rational therapeutic approach to these patients. The failure of traditional antiischemic therapy is confirmed by the frequent unresponsiveness of angina and by the reduced exercise tolerance with administration of sublingual nitrates. Despite that, beta-blockers and calcium-antagonists, when given either alone or in combination, are beneficial in the control of symptoms in some patients. Alternative forms of treatment, based on some pathophysiological hypotheses and clinical observations, include xanthine derivatives, ACE-inhibitors, alpha-blocking agents, imipramine and, in women, oestrogens. The actual clinical usefulness of these drugs, however, is questionable at present, as their efficacy should be evaluated with more adequate studies in the future.


Assuntos
Angina Microvascular/terapia , Antagonistas Adrenérgicos alfa/uso terapêutico , Antagonistas Adrenérgicos beta/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Bloqueadores dos Canais de Cálcio/uso terapêutico , Ensaios Clínicos como Assunto , Árvores de Decisões , Terapia por Estimulação Elétrica , Estrogênios/uso terapêutico , Feminino , Humanos , Imipramina/uso terapêutico , Angina Microvascular/diagnóstico , Angina Microvascular/fisiopatologia , Nitratos/uso terapêutico , Xantinas/uso terapêutico
14.
Chest ; 100(2): 303-6, 1991 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1864099

RESUMO

Fourteen patients (ten men and four women; mean age, 37 years) with lone atrial fibrillation (AF) (1 to 18 months' duration) were evaluated by thyroid function tests, two-dimensional echocardiography, hemodynamics, coronary angiography, and left ventricular endomyocardial biopsy, because of unresponsiveness to the usual antiarrhythmic therapy. The results of the T3, T4, TSH, and TRH tests were normal in all patients; cardiac valves and ventricular and atrial sizes (left atrium less than 40 mm) were within the normal limits; also normal were LVEDP (less than or equal to 10 mm Hg) and EF (greater than 0.50). Histologic findings were abnormal in all cases, with three patients showing cardiomyopathic changes, three other patients showing active myocarditis (lymphocytic in two and eosinophilic in one), and eight patients with nonspecific necrosis or fibrosis or both. Steroids (prednisone; 50 mg/m2 of body surface area daily) used in addition to antiarrhythmic therapy in patients with eosinophilic and lymphocytic active myocarditis were able to cause reversion to sinus rhythm, while the other patients continued to have AF. This study documents that occult myocardial diseases (myocarditis, cardiomyopathy, and nonspecific necrosis or fibrosis) can underlie "primary" AF. The addition of steroids to antiarrhythmic therapy in patients with refractory AF and histologic evidence of active myocarditis seems to be useful in controlling the arrhythmia.


Assuntos
Fibrilação Atrial/patologia , Cardiomiopatias/patologia , Miocárdio/patologia , Adulto , Antiarrítmicos/uso terapêutico , Fibrilação Atrial/tratamento farmacológico , Biópsia , Cardiomiopatias/tratamento farmacológico , Cardiomiopatia Hipertrófica/patologia , Diagnóstico Diferencial , Fibrose Endomiocárdica/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Miocardite/patologia , Necrose , Prednisona/uso terapêutico , Recidiva
15.
Rev. bras. anestesiol ; 39(6): 431-5, nov.-dez. 1989. ilus, tab
Artigo em Português | LILACS | ID: lil-80656

RESUMO

A incidência de hipotensäo ocorrida em pacientes obstétricos submetidas a operaçäo cesariana sob anestesia peridural lombar foi investigada. Cinqüenta parturientes foram aleatoriamente divididas em dois grupos de 25 pacientes cada um, chamado grupo I e II. No grupo I as pacientes receberam 1.000 ml de soluçäo de Ringer durante todo o procedimento anestésico-cirúrgico, e no grupo II as pacientes foram hidratadas com 1.000 ml de soluçäo de Ringer previamente a punçäo lombar e mais 1.000 ml da mesma soluçäo até o fim do procedimento cirúrgico. As pressöes sistólicas e diastólica foram medidas quando as gestantes chegavam ao Centro Cirúrgico e, após a punçäo lombar, a cada cinco minutos até 30 minutos após o momento no qual se obtinha a altura máxima do bloqueio, pesquisado por sensibilidade a picada de agulha. A efedrina foi utilizada sempre que a pressäo arterial caía abaixo de 20% dos valores iniciais. O teste da análise de variância foi utilizado para estabelecer a presença de significância estatística entre as medidas da pressäo arterial, seguindo-se do teste de Student-Newman-Kleuls para determinar quais medidas diferiram das remanescentes. O teste de qui quadrado foi utilizado para avaliar a necessidade do uso do vasopressor entre o grupo I e II. Apesar da pré-hidrataçäo, os resultados mostraram que houve hipotensäo estatisticamente significativa em ambos os grupos. A freqüência da utilizaçäo de vasopressor foi, porém estatísticamente significativa para o grupo I em relaçäo ao grupo II (P < 0,05). Os autores recomendam uma hidrataçäo Ringer, antes da instalaçäo do bloqueio peridural para operaçöes cesarians, pois, embora o procedimento näo evite a possibilidade da ocorrência de hipotensäo arterial, parece diminuir a sua severidade


Assuntos
Gravidez , Humanos , Feminino , Anestesia Epidural/efeitos adversos , Cesárea/efeitos adversos , Hidratação , Hipotensão/prevenção & controle , Anestesia Obstétrica , Hipotensão/induzido quimicamente
16.
Cardiologia ; 34(1): 93-5, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2720719

RESUMO

A case of hypertrophic cardiomiopathy (HCM) mimicking athlete heart, is reported. Performing competitive activity was followed by progression of HCM to cardiac dilation and hypokinesis so that transplant was needed at young age. The Authors suggest a more aggressive approach possibly inclusive of cardiac biopsy when doubtful cases of athlete heart require permission for competitive sports.


Assuntos
Cardiomiopatia Hipertrófica/patologia , Esportes , Adulto , Insuficiência da Valva Aórtica/diagnóstico , Biópsia , Cardiomiopatia Hipertrófica/diagnóstico , Diagnóstico Diferencial , Humanos , Masculino
17.
Rev. bras. anestesiol ; 38(6): 403-8, nov.-dez. 1988. ilus, tab
Artigo em Português | LILACS | ID: lil-74893

RESUMO

O objetivo deste trabalho foi determinar a influência do bloqueador neuromuscular sobre a resposta circulatória conseqüente a laringoscopia e a intubaçäo traqueal, em 47 pacientes Estado Físico I e II ASA a serem submetidos a cirurgia eletiva. Os pacientes foram divididos em três grupos nos quais após a induçäo com tiopental na dose de 5 mg.Kg-1 foi administrado pancurônio (15 pacientes), alcurônio (15 pacientes) e atracúrio (16 pacientes) nas doses de 0,15 mg.Kg-1, 0,3 mg.Kg-1 e 0,5 mg.Kg-1 respectivametne. Todos eles receberam atropina venosa (0,5 mg) previamente a induçäo. A pressäo arterial, a freqüência cardíaca, o produto PAS x FC e o electrocadiograma em D2 foram registrados antes da induçäo, 2 min após a administraçäo do bloqueador neuromuscular, durante a laringoscopia e a passagem do tubo traqueal, no momento da insuflaçäo do balonete 2 e 5 min após a intubaçäo. Foram constatadas nos trê grupos elevaçöes da pressäo arterial, da freqüência cardíaca e do produto PAS x FC, principalmente durante a passagem do tubo traqueal e logo após a insuflaçäo do balonete. Contudo, nenhuma diferença significativa entre os grupos foi observada. Os resultados obtidos sugerem que as alteraçöes dos parâmetros cardiovasculares avaliados säo similares quando do emprego do pancurônio, do alcurônio e do atracúrio para facilitar a intubaçäo traqueal


Assuntos
Adolescente , Adulto , Pessoa de Meia-Idade , Humanos , Masculino , Feminino , Alcurônio , Atracúrio , Frequência Cardíaca , Intubação Intratraqueal , Pancurônio , Pressão Arterial
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