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1.
J Dairy Sci ; 96(3): 1745-54, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23332842

RESUMO

Products of different origin, time of collection, and activities fall under the general term of colostrum and, therefore, great variability in composition as well as in the concentration of its components has been reported in the literature. In the present study, we describe the standardization of a bovine colostrum derivative and the characterization of its bioactive components. Evaluation of the most representative agents (lactoferrin, transferrin, IL-2, IFN-γ, tumor necrosis factor, IgG, and IgA) showed that a marked decrease in active components occurs after the first few hours. Bovine colostrum was, therefore, collected up to the fifth hour after delivery from Holstein cows, in the presence of preservatives, and immediately frozen. A protocol of centrifugation, filtration, and lyophilization was then applied to pools of colostrum from at least 30 cows to obtain a stable, sterile, standardized product. Preservatives were removed by dialysis. Evaluation of the active biological components of colostrum showed that the final product of colostrums contained significant and reproducible amounts of bioactive factors, including cytokines, immunomodulating factors, growth factors, and immunoglobulins. The final product appeared, therefore, as a sterile, pyrogen-free, standardized derivative of bovine colostrum with a high concentration of bioactive components.


Assuntos
Colostro/química , Animais , Carga Bacteriana/veterinária , Bovinos , Colostro/microbiologia , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Imunoglobulina A/análise , Imunoglobulina G/análise , Interferon gama/análise , Interleucina-2/análise , Lactoferrina/análise , Fatores de Tempo , Transferrina/análise , Fator de Necrose Tumoral alfa/análise
2.
Clin Radiol ; 67(3): 207-15, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22154609

RESUMO

AIM: To compare the feasibility, accuracy, and effective radiation dose (ED) of multidetector computed tomography (MDCT) in the detection of coronary artery disease using a combined ED-saving strategy including prospective electrocardiogram (ECG) triggering with a short x-ray window and a body mass index (BMI)-adapted imaging protocol using adaptive statistical iterative reconstruction (ASIR; group 1), in comparison with a prospective ECG triggering strategy alone (group 2). MATERIALS AND METHODS: One hundred and seventy patients scheduled for invasive coronary angiography (ICA) were evaluated. Fourteen patients were not eligible for MDCT. The remaining 156 patients were randomized to group 1 (78 patients) and group 2 (78 patients). Eight and 11 patients in groups 1 and 2, respectively, were excluded after randomization because the patients' heart rates were >65 beats/min. MDCT images were assessed for feasibility, signal-to-noise ration (SNR), and contrast-to-noise ratio (CNR), accuracy in detection of coronary stenoses >50% versus ICA and for ED. RESULTS: The feasibility, SNR, CNR, accuracy in a segment-based and patient-based model were similar in both groups (97 versus 95%, 14.5 ± 3.9 versus 14.2 ± 4.1, 16 ± 4.6 versus 16.5 ± 4.4, 95 versus 94% and 97 versus 99%, respectively). The ED in group 1 was 72% lower than in group 2 (2.1 ± 1.2 versus 7.5 ± 1.8 mSv, respectively; p<0.01). CONCLUSIONS: The use of a multi-parametric ED saving protocol results in a significant reduction in ED without a negative impact on accuracy.


Assuntos
Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Eletrocardiografia , Tomografia Computadorizada Multidetectores/métodos , Idoso , Algoritmos , Índice de Massa Corporal , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador , Sensibilidade e Especificidade , Fatores de Tempo
3.
Int J Cardiol ; 352: 27-32, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35120947

RESUMO

BACKGROUND: Percutaneous coronary interventions (PCI) in calcified coronary artery lesions are associated with impaired stent expansion, higher rate of periprocedural complications and cardiac mortality. Lesion preparation using calcium modifying techniques such as Rotational Atherectomy (RA) or Intravascular Lithotripsy (IVL) has been advocated. Studies comparing these technologies are lacking. We aimed to compare in-stent pressure gradients, evaluated by vessel fractional flow reserve (vFFR), in calcific lesions treated using either RA or IVL. METHODS: Patients undergoing either RA- or IVL-assisted PCI from two European centers were included. Propensity score matching (1:2) was performed to control for potential bias. Primary outcome was post-PCI in-stent pressure gradients calculated by vFFR (vFFRgrad). Secondary outcomes included the proportion of patients with complete functional revascularization defined as distal vFFR post-PCI (vFFRpost) ≥ 0.90. RESULTS: From a cohort of 210 patients, 105 matched patients (70 RA and 35 IVL) were included. Pre-PCI vFFR did not differ between groups (0.65 ± 0.13 RA and 0.67 ± 0.11 IVL). After PCI, in-stent pressure gradients were significantly lower in the IVL group (0.032 ± 0.026 vs 0.043 ± 0.026 in the RA group, p = 0.024). The proportions of vessels with functional complete revascularization was similar between the two groups (32.9% vs. 37.1% in the RA and IVL group, respectively; p = 0.669). CONCLUSIONS: Calcific lesions preparation with IVL is effective and resulted in lower in-stent pressure gradients compared to RA. Approximately one third of the patients undergoing PCI for a severely calcified lesion achieved functional revascularization with no difference between rotational RA and IVL.


Assuntos
Aterectomia Coronária , Doença da Artéria Coronariana , Reserva Fracionada de Fluxo Miocárdico , Litotripsia , Intervenção Coronária Percutânea , Calcificação Vascular , Aterectomia Coronária/métodos , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/cirurgia , Humanos , Resultado do Tratamento , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/cirurgia
4.
Int J Cardiovasc Imaging ; 36(12): 2393-2402, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33205340

RESUMO

Coronary artery calcifications (CAC) are frequently observed in patients referred for coronary CT angiography (CTA). Calcification volume (in mm3) can accurately be assessed during catheterization by optical coherence tomography (OCT). The aim of the present study was to investigate the accuracy of CTA-derived assessment of calcification volume as compared with OCT. 66 calcified plaques (32 vessels) from 31 patients undergoing OCT-guided PCI with coronary CT acquired as a standard of care were included. Coronary CT and OCT images were matched using fiduciary points. Calcified plaques were reconstructed in three dimensions to calculate calcium volume. A Passing-Bablok regression analysis and the Bland-Altman method were used to assess the agreement between imaging modalities. Twenty-seven left anterior descending arteries and 5 right coronary arteries were analyzed. Median calcium volume by CTA and OCT were 18.23 mm3 [IQR 8.09, 36.48] and 10.03 mm3 [IQR 3.6, 22.88] respectively; the Passing-Bablok analysis showed a proportional without a systematic difference (Coefficient A 0.08, 95% CI - 1.37 to 1.21, Coefficient B 1.61, 95% CI 1.45 to 1.84) and the mean difference was 9.69 mm3 (LOA - 10.2 to 29.6 mm3). No differences were observed for minimal lumen area (Coefficient A 0.07, 95% CI - 0.46 to 0.15, Coefficient B 0.85, 95% CI 0.64 to 1.2). CTA volumetric calcium evaluation overestimates calcium volume by 60% compared to OCT. This may allow for an appropriate interpretation of calcific burden in the non-invasive setting. Even in presence of calcific plaques, a good agreement in the MLA assessment was found. Coronary CT may emerge as a tool to quantify calcium burden for invasive procedural planning.


Assuntos
Angiografia por Tomografia Computadorizada , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Tomografia de Coerência Óptica , Calcificação Vascular/diagnóstico por imagem , Idoso , Doença da Artéria Coronariana/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Calcificação Vascular/terapia
5.
Biochim Biophys Acta ; 1442(1): 49-59, 1998 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-9767104

RESUMO

Experimental evidence indicates that the antineoplastic effects of UK101, a goat liver perchloric acid extract, is likely due to one of its constituent proteins: the 14 kDa protein named UK114. The cDNA encoding UK114, obtained by PCR methodologies, contains an open reading frame coding for a protein of 137 amino acids with a theoretical molecular mass of 14298 Da. It shows high sequence homology with a 14 kDa protein identified in human, rat and Mus musculus tissues which is likely involved in the inhibition of cell-free protein synthesis. Northern blot analysis indicated that the transcript is present in variable amounts in a wide range of human tissues. Genomic Southern blots revealed that the UK114 mRNA in goat as well as in human is encoded by a single gene, as is the case in rat. The expression system for UK114 was constructed under the control of the PL promoter from bacteriophage lambda and the cDNA coding region has been highly expressed in Escherichia coli as a thioredoxin fusion protein. The recombinant UK114, purified to homogeneity, is immunoreactive to rabbit antisera prepared against UK101 or native UK114, as well as to sera of UK101-treated cancer patients. It inhibits cell-free protein synthesis at 8 microM concentration.


Assuntos
Escherichia coli/genética , Proteínas de Neoplasias/genética , Sequência de Aminoácidos , Animais , Antígenos de Neoplasias/genética , Sequência de Bases , Clonagem Molecular , DNA Complementar/genética , Humanos , Dados de Sequência Molecular , Coelhos , Ratos , Proteínas Recombinantes/genética , Alinhamento de Sequência
6.
Circulation ; 106(15): 1949-56, 2002 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-12370218

RESUMO

BACKGROUND: Restenosis remains the major limitation of coronary catheter-based intervention. In small vessels, the amount of neointimal tissue is disproportionately greater than the vessel caliber, resulting in higher restenosis rates. In the Randomized Study With the Sirolimus-Eluting Bx Velocity Balloon-Expandable Stent (RAVEL) trial, approximately 40% of the vessels were small (<2.5 mm). The present study evaluates the relationship between angiographic outcome and vessel diameter for sirolimus-eluting stents. METHODS AND RESULTS: Patients were randomized to receive either an 18-mm bare metal Bx VELOCITY (BS group, n=118), or a sirolimus-eluting Bx VELOCITY stent (SES group, n=120). Subgroups were stratified into tertiles according to their reference diameter (RD; stratum I, RD <2.36 mm; stratum II, RD 2.36 mm to 2.84 mm; stratum III, RD >2.84 mm). At 6-month follow-up, the restenosis rate in the SES group was 0% in all strata (versus 35%, 26%, and 20%, respectively, in the BS group). In-stent late loss was 0.01+/-0.25 versus 0.80+/-0.43 mm in stratum I, 0.01+/-0.38 versus 0.88+/-0.57 mm in stratum II, and -0.06+/-0.35 versus 0.74+/-0.57 mm in stratum III (SES versus BS). In SES, the minimal lumen diameter (MLD) remained unchanged (Delta -0.72 to 0.72 mm) in 97% of the lesions and increased (=late gain, DeltaMLD <-0.72 mm) in 3% of the lesions. Multivariate predictors for late loss were treatment allocation (P<0.001) and postprocedural MLD (P= 0.008). CONCLUSIONS: Sirolimus-eluting stents prevent neointimal proliferation and late lumen loss irrespective of the vessel diameter. The classic inverse relationship between vessel diameter and restenosis rate was seen in the bare stent group but not in the sirolimus-eluting stent group.


Assuntos
Angioplastia Coronária com Balão , Angiografia Coronária , Reestenose Coronária/prevenção & controle , Imunossupressores/uso terapêutico , Sirolimo/uso terapêutico , Stents , Reestenose Coronária/diagnóstico por imagem , Vasos Coronários/patologia , Método Duplo-Cego , Humanos , Imunossupressores/administração & dosagem , Sirolimo/administração & dosagem
7.
J Am Coll Cardiol ; 16(5): 1310-4, 1990 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2229780

RESUMO

Although valved conduits have been used successfully in severe forms of right ventricular-pulmonary artery discontinuity, progressive valved conduit stenosis is an important clinical problem. To determine the feasibility of reducing right heart valved conduit stenosis with a balloon expandable stent, a baboon model was used, in which the pulmonary artery was ligated and a right ventricular to pulmonary artery 14 mm bioprosthetic Dacron valved conduit implanted. In five baboons, at an average of 40 months after valved conduit implantation, fibrointimal stenosis at the valve site resulted in narrowing and a mean transconduit pressure gradient of 49 mm Hg (range 33 to 65). A tubular slotted steel stent (1.2 cm long) was deployed within the valved conduit after inflation of an 8 to 15 mm diameter balloon catheter that was introduced through the femoral vein. A stent was delivered to all valved conduits; however, in two baboons, balloon undersizing resulted in stent dislodgment. In the remaining three baboons, the transconduit gradient was reduced by 59% (49 to 20 mm Hg) and right ventricular systolic pressure decreased acutely by 35% (77 to 50 mm Hg). It is concluded that stent deployment is feasible in right ventricular to pulmonary artery stenotic valved conduits and may result in significant hemodynamic improvement. However, successful stent delivery is critically dependent on the proper selection of stent length and balloon diameter.


Assuntos
Prótese Vascular , Cateterismo , Oclusão de Enxerto Vascular/terapia , Stents , Animais , Constrição Patológica/terapia , Ventrículos do Coração/cirurgia , Papio , Artéria Pulmonar/cirurgia
8.
J Am Coll Cardiol ; 17(6 Suppl B): 160B-168B, 1991 May.
Artigo em Inglês | MEDLINE | ID: mdl-2016474

RESUMO

Arterial wall perforation and chronic restenosis represent important factors limiting the clinical application of laser angioplasty. Discrimination of normal and atherosclerotic vessels by laser-excited fluorescence spectroscopy may offer a means of targeting plaque ablation, thereby reducing the frequency of restenosis and transmural perforation. In this study, with use of a 325 nm low power helium-cadmium laser, in vivo endogenous surface fluorescence was excited through a flexible 200 microns optical fiber within a 0.018 in. (0.046 cm) guide wire in contact with the intima of 268 vascular interrogation sites from 48 patients either during open heart surgery or during percutaneous catheterization procedures. Fluorescence spectra could be recorded in all patients in bloodless and blood-filled arteries. Endogenous surface fluorescence was analyzed measuring peak intensity, peak position and shape index of the spectra. Compared with normal wall, noncalcified and calcified coronary atheroma showed a 42% (p less than 0.001) and a 58% (p less than 0.001) decrease of peak intensity, and higher shape index (p less than 0.001 and p less than 0.01, respectively). In addition, peak position was shifted to longer wavelengths for noncalcified coronary atheroma (p less than 0.001). Compared with normal aorta sites, aortic plaques demonstrated a 46% decrease of peak intensity, longer peak position wavelengths (p less than 0.05) and a higher shape index (p less than 0.001). Using an atheroma detection algorithm, prospective analysis of aorta and coronary spectra showed a specificity of 100% for identifying normal sites and a sensitivity of 73% for recognizing atherosclerotic sites.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Arteriosclerose/diagnóstico , Lasers , Espectrometria de Fluorescência/métodos , Adolescente , Adulto , Idoso , Algoritmos , Estudos de Avaliação como Assunto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Espectrometria de Fluorescência/instrumentação
9.
Cardiovasc Res ; 15(11): 637-42, 1981 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7034938

RESUMO

This study is concerned with the mechanisms of human renovascular hypertension. Unilateral partial occlusion of a renal artery was accomplished using a balloon-tipped catheter for occlusive angiography in seven normotensive and 17 primary hypertensive subjects. The renin and circulatory responses were studied during a 60 min reduction of the renal perfusion pressure (RPP) by 50% of control. This stimulus was considered to be safe and strong enough to produce a three to four-fold rise in plasma renin activity. It was observed that: a) systemic (arterial) renin was significantly raised at 5 min, reached a peak at 15 min and continued to be significantly higher than the baseline until the occlusion was removed; b) venous renin and venous arterial difference on the occluded side became elevated after the stimulus and remained so for the duration of the occlusion; c) renin release from the contralateral kidney became partially inhibited; d) in no case did systemic arterial pressure, heart rate or cardiac output change during the studies; e) renin and circulatory patterns were similar in normotensive and hypertensive subjects. It is concluded that in humans unilateral RPP reduction duplicates the renin pattern of the Goldblatt kidney, but does not duplicate the circulatory response. This evidence applies to a 1 h renal artery occlusion and does not exclude the possibility that renin may have a role in a rise in blood pressure following renal artery stenosis of longer duration.


Assuntos
Hemodinâmica , Hipertensão Renal/fisiopatologia , Hipertensão Renovascular/fisiopatologia , Circulação Renal , Renina/sangue , Pressão Sanguínea , Humanos
10.
Eur Heart J Cardiovasc Imaging ; 16(12): 1366-73, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25911117

RESUMO

AIMS: To evaluate the feasibility of ultra-low-dose CT for left atrium and pulmonary veins using new model-based iterative reconstruction (MBIR) algorithm. METHODS AND RESULTS: Two hundred patients scheduled for catheter ablation were randomized into two groups: Group 1 (100 patients, Multidetector row CT (MDCT) with MBIR, no ECG triggering, tube voltage and tube current of 100 kV and 60 mA, respectively) and Group 2 [100 patients, MDCT with adaptive statistical iterative reconstruction algorithm (ASIR), no ECG triggering, and kV and mA tailored on patient BMI]. Image quality, CT attenuation, image noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) of left atrium (LA) and pulmonary veins, and effective dose (ED) were evaluated for each exam and compared between two groups.No significant differences between groups in terms of population characteristics, cardiovascular risk factors, anatomical features, prevalence of persistent atrial fibrillation and image quality score. Statistically significant differences were found between Group 1 and Group 2 in mean attenuation, SNR, and CNR of LA. Significantly, lower values of noise were found in Group 1 versus Group 2. Group 1 showed a significantly lower mean ED in comparison with Group 2 (0.41 ± 0.04 versus 4.17 ± 2.7 mSv). CONCLUSION: The CT for LA and pulmonary veins imaging using MBIR is feasible and allows examinations with very low-radiation exposure without loss of image quality.


Assuntos
Fibrilação Atrial/diagnóstico por imagem , Átrios do Coração/diagnóstico por imagem , Veias Pulmonares/diagnóstico por imagem , Doses de Radiação , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Fibrilação Atrial/cirurgia , Técnicas de Imagem de Sincronização Cardíaca , Meios de Contraste , Estudos de Viabilidade , Feminino , Humanos , Iopamidol/análogos & derivados , Masculino , Pessoa de Meia-Idade , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Razão Sinal-Ruído , Software
11.
Hypertension ; 6(4): 586-8, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6746088

RESUMO

We report the case of a 9-year-old boy suffering from exzematous dermatitis who was treated for 6 years with a daily dose of 100 mg of a dermatological ointment containing 9 alpha-fluoroprednisolone-21-acetate. At examination the patient's blood pressure was persistently 230/160 mm Hg and was considered essential in origin after secondary forms of arterial hypertension had been excluded. Treatment with nifedipine and labetalol lowered the blood pressure to 150/100 mm Hg. When we became aware of the dermatological treatment, we advised its discontinuance. In the subsequent 7 days, the blood pressure fell to hypotensive levels (75/40 mm Hg) and then became normal a few days after discontinuance of the antihypertensive therapy. This case suggests that prolonged use of topical steroids, commonly prescribed for skin diseases, may cause hypertension, especially in childhood.


Assuntos
Fluprednisolona/análogos & derivados , Hipertensão/induzido quimicamente , Administração Tópica , Pressão Sanguínea/efeitos dos fármacos , Criança , Eczema/tratamento farmacológico , Fluprednisolona/administração & dosagem , Fluprednisolona/efeitos adversos , Humanos , Hipertensão/tratamento farmacológico , Labetalol/uso terapêutico , Masculino , Nifedipino/uso terapêutico , Fatores de Tempo
12.
Hypertension ; 5(4 Pt 2): II85-90, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6222973

RESUMO

Calcium channel blockers have a selective action on the cardiovascular system. They reduce the energy requirement of the heart, reduce vascular smooth muscle tone, and increase systemic blood flow. Vasodilatation occurs in both the systemic and the pulmonary systems to an extent proportional to the baseline level of vascular resistance, and results in reduction of blood pressure when it is elevated. Thus, these blockers are useful in patients with high blood pressure. Clinical experience of calcium channel blockers in hypertension is so far confined almost exclusively to verapamil and nifedipine. This article reviews the advantages and limitations of these two compounds, their acute hemodynamic effects in hypertensive subjects, and their use in the treatment of hypertensive emergencies, hypertensive encephalopathy, and pheochromocytoma, and as ventricular afterload reducing agents in hypertensive left ventricular failure. Similarities in the effects of nifedipine on systemic and pulmonary vascular tone are presented as evidence that altered intracellular Ca++ concentration is involved in the vasoconstriction seen in both systems in systemic high blood pressure. They also provide support for the hypothesis that inappropriate Ca++ handling may be involved in maintaining elevated blood pressure in human hypertension.


Assuntos
Bloqueadores dos Canais de Cálcio/administração & dosagem , Hipertensão/tratamento farmacológico , Nifedipino/administração & dosagem , Piridinas/administração & dosagem , Verapamil/administração & dosagem , Neoplasias das Glândulas Suprarrenais/complicações , Anti-Hipertensivos/administração & dosagem , Cardiomegalia/tratamento farmacológico , Quimioterapia Combinada , Insuficiência Cardíaca/tratamento farmacológico , Hemodinâmica/efeitos dos fármacos , Humanos , Masculino , Metildopa/administração & dosagem , Feocromocitoma/complicações
13.
FEBS Lett ; 393(2-3): 147-50, 1996 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-8814279

RESUMO

UK114 is a tumor antigen expressed by various malignant neoplasms. The complete amino acid sequence of UK114 purified from goat liver has been determined by automated Edman degradation of CNBr and endoproteinase Lys-C peptides. The protein contains 137 amino acid residues. which corresponds to a molecular mass of 14,229 Da. MALDI-TOF analysis resulted in a molecular weight of 14,290, suggesting that the N-terminal Met residue is acetylated. Sequence comparison shows that UK114 from goat liver (1) has 77% identity with a previously described 23 kDa protein from rat liver (Levy-Favatier et al. (1993) Eur. J. Biochem. 212, 665-673), (2) shares a very high degree of similarity with a family of prokaryotic and eukaryotic hypothetic proteins whose function have not yet been characterized, and (3) exhibits a significant similarity to a group of tumor-associated antigens which belongs to a superfamily of heat shock proteins, acting as possible targets for the host's antitumor immunity.


Assuntos
Antígenos de Neoplasias/química , Proteínas de Neoplasias/química , Sequência de Aminoácidos , Animais , Antígenos de Neoplasias/isolamento & purificação , Autoanálise , Brometo de Cianogênio , Cabras , Humanos , Fígado/química , Metaloendopeptidases , Dados de Sequência Molecular , Proteínas de Neoplasias/isolamento & purificação , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/isolamento & purificação , Ratos , Homologia de Sequência de Aminoácidos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
14.
Am J Med ; 87(1): 15-21, 1989 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2741976

RESUMO

PURPOSE: In 24 patients with stable spontaneous and effort-related angina, ischemic episodes at rest were not preceded by changes in circulatory variables (heart rate, systemic and pulmonary arterial pressures) that may raise the myocardial oxygen consumption. We interpreted these episodes as caused by critical and reversible coronary flow reduction at the site of a stenotic lesion, and evaluated the clinical efficacy of nifedipine and propranolol in the treatment of this condition. PATIENTS AND METHODS: The study was randomized, placebo-controlled, and crossover in design. Nineteen of the 24 subjects were men (mean group age, 59 years; range, 47 to 65 years). The study consisted of four four-day periods. The first and the fourth periods, during which patients received placebo, were single-blind. The treatment consisted of 80 mg of propranolol or 20 mg of nifedipine administered four times daily. The second and the third periods, during which patients received propranolol or nifedipine crossing over to the alternative drug in the next period, were double-blind and separated by a 24-hour interval. RESULTS: Propranolol fully abolished or reduced the number of spontaneous ischemic episodes in a significantly larger proportion of patients than did nifedipine; it was also effective in several cases in which nifedipine had failed or had even caused a paradoxic effect. Quantitative angiographic evaluation of the influences of nifedipine (Group 1, 12 patients, 10 mg sublingually) and propranolol (Group 2, 12 patients, 0.1 mg/kg intravenously) on the residual lumen diameter of one significant coronary stenosis in each patient showed that (1) after nifedipine, the lumen was unchanged in one, augmented in seven, and reduced in four cases; (2) variations ranged between +1.59 and -1.2 mm, and their direction correlated closely with the influence of oral nifedipine on the episodes of spontaneous ischemia; and (3) in no case did treatment with propranolol vary the stenosis lumen by more than 0.3 mm. CONCLUSION: In this form of angina, a number of lesions seem to offer a compliant substrate for vasomotion and, possibly, for critical changes in flow. The vasomotor influences of nifedipine on these lesions are variable as well as the efficacy of the drug on the manifestations of ischemia at rest. Propranolol produces no important variations of the coronary stenotic lesions, causes a decrease of heart rate that facilitates coronary flow in diastole, and reduces the baseline metabolic demand of the heart so that the threshold of ischemia during critical reduction of coronary flow may become elevated.


Assuntos
Angina Pectoris/tratamento farmacológico , Vasos Coronários/inervação , Hemodinâmica/efeitos dos fármacos , Nifedipino/uso terapêutico , Propranolol/uso terapêutico , Sistema Vasomotor/efeitos dos fármacos , Idoso , Eletrocardiografia , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica , Distribuição Aleatória
15.
Am J Cardiol ; 63(17): 1198-202, 1989 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-2711989

RESUMO

To test whether calcium channel blockade plays a similar role in the coronary vasomotion of patients with syndrome X (n = 29) and patients with Prinzmetal's angina pectoris (n = 12), quantitative angiography was used to evaluate the effect of nifedipine (10 mg, sublingually) on the lumen diameter of proximal, mid and distal thirds of normal epicardial branches. The main differences in the coronary vasomotor reaction were uniform vasodilatation in Prinzmetal's angina and a variable response to syndrome X, and a greater increase in the coronary lumen in patients with Prinzmetal's angina as compared with those with syndrome X who showed vasodilatation. The variable response in syndrome X was not related to changes in diastolic pressure and cardiac output. Patients showing coronary constriction were those who responded to nifedipine with a higher degree of tachycardia, which might suggest a neural participation in the paradoxic reaction to this drug. In the Prinzmetal group, on the contrary, at a similar heart rate increase the pattern was invariably vasodilatation. Thus, calcium ions appear to have a different role in the coronary smooth muscle contractility of the 2 series of patients; in fact, in Prinzmetal's angina nifedipine relaxed the coronary arteries to a greater degree and made them unresponsive to stimuli that were still able to cause vasoconstriction in patients with syndrome X.


Assuntos
Angina Pectoris Variante/fisiopatologia , Cálcio/fisiologia , Dor no Peito/fisiopatologia , Vasos Coronários/efeitos dos fármacos , Nifedipino/farmacologia , Adulto , Idoso , Angina Pectoris Variante/diagnóstico por imagem , Dor no Peito/diagnóstico por imagem , Vasos Coronários/fisiologia , Feminino , Hemodinâmica/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Esforço Físico , Radiografia , Síndrome
16.
Am J Cardiol ; 85(7): 821-5, 2000 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10758920

RESUMO

The Carbostent is a new balloon-expandable, stainless steel, tubular stent with innovative multicellular design and unique turbastratic carbon coating (Carbofilm). This open nonrandomized 2-center study assesses the immediate and long-term clinical and angiographic outcomes after Carbostent implantation in patients with native coronary artery disease. The Carbostent was implanted in 112 patients with 132 de novo lesions. Most patients (55%) had unstable angina, and 38% of lesions were type B2-C. The mean lesion length was 12.5 +/- 7.0 mm, and 29% of lesions were > 15 mm in length. No stent deployment failure occurred, as well as acute or sub-acute stent thrombosis. The 6-month event-free survival was 84 +/- 4%. One patient with a stented right coronary artery and no restenosis at the angiographic follow-up died after 6 months of fatal infarction due to abrupt closure of a nontarget vessel. In-hospital non-Q-wave myocardial infarction occurred in 1 patient, and 11 patients had repeat target lesion revascularization (target lesion revascularization rate 10%). The 6-month angiographic follow-up was obtained in 108 patients (96%) (127 lesions). Angiographic restenosis rate was 11%. The loss index was 0.29 +/- 0.28. The results of this study indicate a potential benefit of Carbostent for the prevention of stent thrombosis and restenosis in these relatively high-risk patients. A larger trial is being planned to confirm these promising results.


Assuntos
Angina Instável/diagnóstico por imagem , Angina Instável/terapia , Angioplastia Coronária com Balão , Materiais Revestidos Biocompatíveis , Angiografia Coronária , Stents , Adulto , Idoso , Carbono , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Estudos Retrospectivos , Resultado do Tratamento
17.
Am J Cardiol ; 88(3): 248-52, 2001 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-11472702

RESUMO

Intimal hyperplasia within the body of the stent is the primary mechanism for in-stent restenosis; however, stent edge restenosis has been described after brachytherapy. Our current understanding about the magnitude of in vivo intimal hyperplasia and edge restenosis is limited to data obtained primarily from select, symptomatic patients requiring repeat angiography. The purpose of this study was to determine the extent and distribution of intimal hyperplasia both within the stent and along the stent edge in relatively nonselect, asymptomatic patients scheduled for 6-month intravascular ultrasound (IVUS) as part of a multicenter trial: Heparin Infusion Prior to Stenting. Planar IVUS measurements 1 mm apart were obtained throughout the stent and over a length of 10 mm proximal and distal to the stent at index and follow-up. Of the 179 patients enrolled, 140 returned for repeat angiography and IVUS at 6.4 +/- 1.9 months and had IVUS images adequate for analysis. Patients had 1.2 +/- 0.6 Palmaz-Schatz stents per vessel. There was a wide individual variation of intimal hyperplasia distribution within the stent and no mean predilection for any location. At 6 months, intimal hyperplasia occupied 29.3 +/- 16.2% of the stent volume on average. Lumen loss within 2 mm of the stent edge was due primarily to intimal proliferation. Beyond 2 mm, negative remodeling contributed more to lumen loss. Gender, age, vessel location, index plaque burden, hypercholesterolemia, diabetes, and tobacco did not predict luminal narrowing at the stent edges, but diabetes, unstable angina at presentation, and lesion length were predictive of in-stent intimal hyperplasia. In a non-radiation stent population, 29% of the stent volume is filled with intimal hyperplasia at 6 months. Lumen loss at the stent edge is due primarily to intimal proliferation.


Assuntos
Doença das Coronárias/patologia , Stents , Túnica Íntima/patologia , Doença das Coronárias/terapia , Feminino , Seguimentos , Humanos , Hiperplasia/etiologia , Hiperplasia/patologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Estudos Prospectivos , Recidiva , Stents/efeitos adversos
18.
Int J Oncol ; 8(3): 543-8, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21544394

RESUMO

The monoclonal antibody (P-3 mAb) and the rabbit immune sera (RIS) recognizing a 14 kDa perchloric acid soluble protein extracted from goat liver (UK 114), locate this antigen on the cell membrane of several human cancer cell lines. UK 114-positive cells (e.g. HT 29 and KATO VI cells) undergo antibody-dependent cytolysis bl vitro. In nu/nu mice bearing xenografted HT 29 cells, tumor growth was markedly impaired by peri-tumoral injection of anti-UK 114 antibodies. These experiments suggest that human tumors expressing UK 114 over the cell membrane may undergo antibody-mediated cytolysis and growth control.

19.
Int J Oncol ; 10(4): 779-85, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21533445

RESUMO

UK114 is a 14 kDa protein identified in the perchloric acid soluble extract of goat liver. Anti-UK114 antibodies identify this protein as expressed by the membrane of human cancer cells. In the present study, anti-UK114 antibodies were detected in the sera of cancer patients by ELISA and by immunofluorescence tests using human cancer cell lines as a target. UK114 protein is antigenic in cancer patients. Human anti-UK114 antibodies have cytolytic effects in vitro and their presence correlates with inhibition of growth of human carcinoma cells xenografted in nu/nu mice. This finding may open new prospects for immunotherapy.

20.
Chest ; 95(3): 702-4, 1989 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2920607

RESUMO

A 63-year-old woman had chest pain that worsened when nifedipine was given. She was found to have a right coronary-to-thorax angioma/fistula. Acute nifedipine administration elicited precordial symptoms, associated with ischemic changes in the inferior ECG leads and an obvious vasodilatation of the fistulous tract, suggesting that a nifedipine-induced "steal" phenomenon might be responsible for the paradoxic clinical response.


Assuntos
Doença das Coronárias/induzido quimicamente , Anomalias dos Vasos Coronários/complicações , Nifedipino/efeitos adversos , Doença das Coronárias/diagnóstico por imagem , Eletrocardiografia , Feminino , Humanos , Pessoa de Meia-Idade , Radiografia
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