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1.
Hum Reprod ; 37(5): 954-968, 2022 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-35220429

RESUMEN

STUDY QUESTION: Is it safe to perform controlled ovarian stimulation (COS) for fertility preservation before starting anticancer therapies or ART after treatments in young breast cancer patients? SUMMARY ANSWER: Performing COS before, or ART following anticancer treatment in young women with breast cancer does not seem to be associated with detrimental prognostic effect in terms of breast cancer recurrence, mortality or event-free survival (EFS). WHAT IS KNOWN ALREADY: COS for oocyte/embryo cryopreservation before starting chemotherapy is standard of care for young women with breast cancer wishing to preserve fertility. However, some oncologists remain concerned on the safety of COS, particularly in patients with hormone-sensitive tumors, even when associated with aromatase inhibitors. Moreover, limited evidence exists on the safety of ART in breast cancer survivors for achieving pregnancy after the completion of anticancer treatments. STUDY DESIGN, SIZE, DURATION: The present systematic review and meta-analysis was carried out by three blinded investigators using the keywords 'breast cancer' and 'fertility preservation'; keywords were combined with Boolean operators. Eligible studies were identified by a systematic literature search of Medline, Web of Science, Embase and Cochrane library with no language or date restriction up to 30 June 2021. PARTICIPANTS/MATERIALS, SETTING, METHODS: To be included in this meta-analysis, eligible studies had to be case-control or cohort studies comparing survival outcomes of women who underwent COS or ART before or after breast cancer treatments compared to breast cancer patients not exposed to these strategies. Survival outcomes of interest were cancer recurrence rate, relapse rate, overall survival and number of deaths. Adjusted relative risk (RR) and hazard ratio (HR) with 95% CI were extracted. When the number of events for each group were available but the above measures were not reported, HRs were estimated using the Watkins and Bennett method. We excluded case reports or case series with <10 patients and studies without a control group of breast cancer patients who did not pursue COS or ART. Quality of data and risk of bias were assessed using the Newcastle-Ottawa Assessment Scale. MAIN RESULTS AND THE ROLE OF CHANCE: A total of 1835 records were retrieved. After excluding ineligible publications, 15 studies were finally included in the present meta-analysis (n = 4643). Among them, 11 reported the outcomes of breast cancer patients who underwent COS for fertility preservation before starting chemotherapy, and 4 the safety of ART following anticancer treatment completion. Compared to women who did not receive fertility preservation at diagnosis (n = 2386), those who underwent COS (n = 1594) had reduced risk of recurrence (RR 0.58, 95% CI 0.46-0.73) and mortality (RR 0.54, 95% CI 0.38-0.76). No detrimental effect of COS on EFS was observed (HR 0.76, 95% CI 0.55-1.06). A similar trend of better outcomes in terms of EFS was observed in women with hormone-receptor-positive disease who underwent COS (HR 0.36, 95% CI 0.20-0.65). A reduced risk of recurrence was also observed in patients undergoing COS before neoadjuvant chemotherapy (RR 0.22, 95% CI 0.06-0.80). Compared to women not exposed to ART following completion of anticancer treatments (n = 540), those exposed to ART (n = 123) showed a tendency for better outcomes in terms of recurrence ratio (RR 0.34, 95% CI 0.17-0.70) and EFS (HR 0.43, 95% CI 0.17-1.11). LIMITATIONS, REASONS FOR CAUTION: This meta-analysis is based on abstracted data and most of the studies included are retrospective cohort studies. Not all studies had matching criteria between the study population and the controls, and these criteria often differed between the studies. Moreover, rate of recurrence is reported as a punctual event and it is not possible to establish when recurrences occurred and whether follow-up, which was shorter than 5 years in some of the included studies, is adequate to capture late recurrences. WIDER IMPLICATIONS OF THE FINDINGS: Our results demonstrate that performing COS at diagnosis or ART following treatment completion does not seem to be associated with detrimental prognostic effect in young women with breast cancer, including among patients with hormone receptor-positive disease and those receiving neoadjuvant chemotherapy. STUDY FUNDING/COMPETING INTEREST(S): Partially supported by the Associazione Italiana per la Ricerca sul Cancro (AIRC; grant number MFAG 2020 ID 24698) and the Italian Ministry of Health-5 × 1000 funds 2017 (no grant number). M.L. acted as consultant for Roche, Pfizer, Novartis, Lilly, AstraZeneca, MSD, Exact Sciences, Gilead, Seagen and received speaker honoraria from Roche, Pfizer, Novartis, Lilly, Ipsen, Takeda, Libbs, Knight, Sandoz outside the submitted work. F.S. acted as consultant for Novartis, MSD, Sun Pharma, Philogen and Pierre Fabre and received speaker honoraria from Roche, Novartis, BMS, MSD, Merck, Sun Pharma, Sanofi and Pierre Fabre outside the submitted work. I.D. has acted as a consultant for Roche, has received research grants from Roche and Ferring, has received reagents for academic clinical trial from Roche diagnostics, speaker's fees from Novartis, and support for congresses from Theramex and Ferring outside the submitted work. L.D.M. reported honoraria from Roche, Novartis, Eli Lilly, MSD, Pfizer, Ipsen, Novartis and had an advisory role for Roche, Eli Lilly, Novartis, MSD, Genomic Health, Pierre Fabre, Daiichi Sankyo, Seagen, AstraZeneca, Eisai outside the submitted work. The other authors declare no conflict of interest. The funding organizations had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript and decision to submit the manuscript for publication. REGISTRATION NUMBER: N/A.


Asunto(s)
Neoplasias de la Mama , Supervivientes de Cáncer , Preservación de la Fertilidad , Neoplasias de la Mama/tratamiento farmacológico , Femenino , Humanos , Recurrencia Local de Neoplasia , Embarazo , Estudios Retrospectivos
2.
Hum Reprod ; 36(2): 381-389, 2021 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-33289029

RESUMEN

STUDY QUESTION: What is the risk of recurrence in young breast cancer survivors who undergo ARTs following completion of anticancer treatment? SUMMARY ANSWER: ART in breast cancer survivors does not appear to have a negative impact on disease-free survival. WHAT IS KNOWN ALREADY: In healthy women, fertility treatment does not increase the risk of developing breast cancer. At the time of breast cancer diagnosis and before starting anticancer treatments, several studies have shown the safety of performing ART. However, the safety of ART in breast cancer survivors following completion of anticancer treatment remains under-investigated. In general, breast cancer survivors are counselled to avoid any hormonal treatment but there are limited data available on the effect of short exposure to high oestradiol levels during ART. The largest study in this regard included 25 breast cancer survivors exposed to ART and did not show a detrimental effect of ART on patient survival. Hence, taking into account that pregnancy after breast cancer does not affect cancer prognosis, defining the safety of ART in breast cancer survivors remains a priority. STUDY DESIGN, SIZE, DURATION: We conducted a retrospective multicentric matched cohort study including a cohort of breast cancer survivors who underwent ART (exposed patients) between January 2006 and December 2016. Exposed patients who were eligible for the study were matched according to known breast cancer prognostic factors. Matched breast cancer survivors did not undergo ART (non-exposed patients) and were disease-free for a minimum time that was not less than the time elapsed between breast cancer diagnosis and first ART for the matched ART-exposed patients. PARTICIPANTS/MATERIALS, SETTING, METHODS: Data were retrieved from all survivors who had been diagnosed with breast cancer in eight participating centres at an age of ≤40 years, without metastasis, ongoing pregnancy, pre-existing neoplasia or ovarian failure. ART included ovarian stimulation for IVF/ICSI, clomiphene citrate treatment and hormone replacement therapy for embryo transfer. Data were collected from an oncological database for the selection of breast cancer patients in the non-exposed group. Exposed patients were matched (1:2) for germline BRCA status, tumour stage, anticancer treatment and age, whenever feasible. Matched groups were compared at baseline according to characteristics using conditional logistic regression. Kaplan-Meier curves were constructed to compare time to recurrence between groups, with the time of ART as starting point that has been adjusted in the non-exposed group. The analyses were performed using Stata IC/15.1. MAIN RESULTS AND THE ROLE OF CHANCE: A total of 39 breast cancer patients in the ART group were eligible for the analysis and were matched with 73 controls. There was no statistical difference between the two groups for the presence of BRCA mutation, tumour characteristics, use of (neo)adjuvant chemotherapy and of adjuvant endocrine therapy. Exposed patients were younger than non-exposed patients (mean age 31.8 vs 34.3 years, respectively; P < 0.001). In the ART group, 89.7% were nulliparous at diagnosis compared to 46.6% of controls (P < 0.001). ART was performed at a mean age of 37.1 years old, after a median time of 4.1 years following breast cancer diagnosis (range: 1.5-12.5). Median anti-Müllerian hormone at the time of ART was 0.28 ng/ml (range: 0-4.4) and median serum oestradiol peak level was 696.5 pg/ml (range: 139.7-4130). Median follow-up time from first attempt of ART was 4.6 years (range: 2.4-12.5) in the ART group. Adjusted follow-up time for the non-exposed group was 6.9 years (range: 1.1-16.5 years) (P = 0.004). In the ART group, 59% of patients had a pregnancy after breast cancer compared to 26% in the non-exposed patients (P = 0.001). Breast cancer relapsed in 7.7% versus 20.5% women in the ART and non-exposed groups, respectively (hazard ratio 0.46, 95% CI 0.13-1.62, P = 0.23). Median time to relapse was 1.3 (range: 0.3-2.7) years versus 4.5 (range: 0.4-11.1) years after ART and adjusted time in the ART and non-exposed groups, respectively (P = 0.14). LIMITATIONS, REASONS FOR CAUTION: Although this is the first and largest multicentric study addressing the impact of ART on breast cancer recurrence to provide data on oestrogen exposure, only a small number of patients could be included. This reflects the reluctance of breast cancer survivors and/or oncologists to perform ART, and highlights the need for a prospective data registry to confirm the safety of this approach. This would offer the possibility for these patients, who are at a high risk of infertility, to fully benefit from ART. WIDER IMPLICATIONS OF THE FINDINGS: Although recent studies have proven that pregnancy after breast cancer has no detrimental impact on prognosis, counselling patients about the safety of ART remains challenging. Our study provides reassuring data on the use of ART in breast cancer survivors with favourable prognostic factors, for when natural conception fails. STUDY FUNDING/COMPETING INTEREST(S): M.C. and I.D. are funded by FNRS, Télévie-FNRS and Fonds Erasme. M.D.V. is a CooperSurgical scientific advisory board member and receives lecture fees for MSD, Gedeon-Richter and Ferring, outside the submitted work. M.L. has acted as a consultant for Roche and Novartis and has received honoraria from Theramex, Roche, Lilly, Pfizer, Novartis and Takeda, outside the submitted work. I.D. has acted as a consultant for ROCHE and has received speaker's fees from Novartis, outside the submitted work. E.d.A. has received honoraria and is a Roche/GNE, Novartis, SeaGen and Zodiac scientific advisory board member, has received travel grants from Roche/GNE and GSK/Novartis, and has received research grants from Roche/GNE, Astra-Zeneca, GSK/Novartis and Servier, outside the submitted work. A.D. is a recipient of a research grant from Ferring Pharmaceuticals and receives lecture and/or consultancy fees from Merck, Gedeon-Richter and Ferring Pharmaceuticals, outside the submitted work. The remaining authors have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: N/A.


Asunto(s)
Neoplasias de la Mama , Supervivientes de Cáncer , Adulto , Neoplasias de la Mama/tratamiento farmacológico , Estudios de Cohortes , Femenino , Humanos , Masculino , Recurrencia Local de Neoplasia , Embarazo , Estudios Prospectivos , Estudios Retrospectivos
3.
Ultrasound Obstet Gynecol ; 52(6): 776-783, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25130705

RESUMEN

OBJECTIVES: To evaluate postmortem ultrasound (PM-US) for minimally invasive autopsy, and to demonstrate its feasibility, sensitivity and specificity, as compared with conventional autopsy, in detecting major congenital abnormalities. METHODS: Over a 19-month study period from 1 March 2012 to 30 September 2013, we recruited from a referral hospital 88 consecutive fetuses, at 11-40 weeks' gestation, which had undergone termination, miscarriage or intrauterine fetal death. We performed PM-US using different transducers and compared the data with those from conventional autopsy. The latter was performed, according to the Societé Francaise de Foetopathologie (France) guidelines, by experienced perinatal pathologists who were blinded to the ultrasound data. RESULTS: Complete virtual autopsy by ultrasound was possible in 95.5% of the cases. The sensitivity of PM-US for detecting brain abnormalities was 90.9% (95% CI, 58.7-99.8%) and the specificity was 87.3% (95% CI, 75.5-94.7%). In 20% of cases, a neuropathological examination was not possible due to severe maceration. The sensitivity for detection of thoracic abnormalities was 88.9% (95% CI, 65.3-98.6%) and the specificity was 92.8% (95% CI, 84.1-97.6%), and the sensitivity for detection of abdominal anomalies was 85.7% (95% CI, 57.2-98.2%) and the specificity was 94.6% (95% CI, 86.7-98.5%). CONCLUSION: This pilot study confirms the feasibility of PM-US for virtual autopsy as early as 11 weeks' gestation. This new technique shows high sensitivity and specificity in detecting congenital structural abnormalities as compared with conventional autopsy. Copyright © 2014 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Autopsia/instrumentación , Anomalías Congénitas/diagnóstico , Ultrasonografía Prenatal/métodos , Autopsia/métodos , Estudios de Factibilidad , Femenino , Edad Gestacional , Humanos , Proyectos Piloto , Embarazo , Estudios Prospectivos , Sensibilidad y Especificidad
4.
Sci Rep ; 13(1): 1014, 2023 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-36653377

RESUMEN

In a single crystalline Si particle, we observed a huge amplification of the Raman peak at 521 cm-1. With an AFM microscope, coupled with a Micro-Raman spectrometer, we investigate a single Si particle at wavelengths of 532 nm, 633 nm, and 785 nm. As observed by transmission electron microscopy, it has an octahedral shape of 150 nm in size. Thermal effects were detected on the Raman peak when the laser radiation, trapped inside, determines the heating of the particle up to its fusion. In these cases, the Raman peak splits into two components, the first at the crystal position and the other shifted at a lower value. The data permit the identification of the amplification mechanism of the Raman peak as trapped radiation moving forward and backwards into the particle. The thermal effects are attributed to phonon confinement and reduced thermal exchange with the surrounding. The present results are discussed in light of local order, the uncertainty principle, and phonon dispersion curves, and corroborated by shape-dependent simulation of absorption, scattering, and extinction behaviour.

5.
Nat Med ; 2(1): 35-40, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8564835

RESUMEN

Tissue factor is a transmembrane protein that activates the extrinsic coagulation pathway by binding factor VII. Endothelial cells, being in contact with circulating blood, do not normally express tissue factor. Here we provide evidence that oxygen free radicals induce tissue factor messenger RNA transcription and expression of tissue factor procoagulant activity in endothelial cells in culture. Isolated, perfused rabbit hearts exposed to exogenous oxygen free radicals also showed a marked increase in tissue factor activity within the coronary circulation. Furthermore, in ex vivo and in vivo hearts subjected to ischemia and reperfusion, a condition associated with a production of oxygen free radicals in large amounts, a marked increase in tissue factor activity occurred. This phenomenon could be abolished by oxygen radical scavengers. This increase in tissue factor activity during postischemic reperfusion was accompanied by a significant decrease in coronary flow, suggesting that increase in tissue factor activity with the consequent activation of the coagulation cascade might impair coronary flow during reperfusion and possibly contribute to the occurrence of reperfusion injury.


Asunto(s)
Circulación Coronaria , Endotelio Vascular/metabolismo , Corazón/efectos de los fármacos , Isquemia Miocárdica/fisiopatología , Reperfusión Miocárdica , Tromboplastina/biosíntesis , Animales , Northern Blotting , Células Cultivadas , Cicloheximida/farmacología , Endotelio Vascular/efectos de los fármacos , Depuradores de Radicales Libres/farmacología , Radicales Libres/farmacología , Expresión Génica , Corazón/fisiología , Técnicas In Vitro , Isquemia Miocárdica/metabolismo , Oxígeno , ARN Mensajero/biosíntesis , Conejos , Flujo Sanguíneo Regional , Xantina , Xantina Oxidasa/farmacología , Xantinas/farmacología
6.
Minerva Ginecol ; 63(2): 171-80, 2011 Apr.
Artículo en Italiano | MEDLINE | ID: mdl-21508905

RESUMEN

AIM: The aim of this paper was to compare two anti-incontinence procedures during laparoscopic sacrocolpopexy (LSC) to prevent postoperative stress urinary incontinence (SUI). METHODS: Retrospective analysis of 90 continent hysterectomized patients with vaginal vault prolapse treated with LSC plus colposuspension (group A, N.=30), LSC plus retropubic mid-urethral sling (group B, N.=30), or LSC alone (group C, N.=30). RESULTS: De novo SUI rate resulted significantly (P<0.05) lower in group B than C. No difference was detected regarding de novo urge urinary incontinence. Total reoperation rate resulted significantly (P<0.05) higher in group A than B and lower in group B than C. CONCLUSION: When associated to LSC for preventing SUI, colposuspension and retropubic mid-urethral sling are effective and safe, even if mid-urethral sling seems to provide the best risk/benefit profile.


Asunto(s)
Laparoscopía , Prolapso de Órgano Pélvico/cirugía , Cabestrillo Suburetral , Incontinencia Urinaria de Esfuerzo/prevención & control , Femenino , Procedimientos Quirúrgicos Ginecológicos/efectos adversos , Procedimientos Quirúrgicos Ginecológicos/métodos , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Incontinencia Urinaria de Esfuerzo/etiología
7.
Minerva Ginecol ; 63(3): 213-8, 2011 Jun.
Artículo en Italiano | MEDLINE | ID: mdl-21654606

RESUMEN

AIM: The aim of this paper was to investigate the sex ratio in the offspring of pregnant patients with polycystic ovary syndrome (PCOS). METHODS: Analysis of 70 pregnant patients with PCOS who achieve a pregnancy without any kind of treatment, and having as controls 63 healthy pregnant women without any feature of PCOS. RESULTS: No significant difference in sex ratio was detected between PCOS and controls, even if it resulted significantly different in the full-blown and non-PCO phenotypes. CONCLUSION: The PCOS phenotypes influenced the sex ratio in the offspring, suggesting that environmental factors could play a role in determination of the offspring gender.


Asunto(s)
Síndrome del Ovario Poliquístico/genética , Complicaciones Neoplásicas del Embarazo/genética , Razón de Masculinidad , Femenino , Humanos , Recién Nacido , Masculino , Fenotipo , Embarazo
8.
ESMO Open ; 6(6): 100300, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34775302

RESUMEN

BACKGROUND: Knowledge is growing on the safety of assisted reproductive techniques (ART) in cancer survivors. No data exist, however, for the specific population of breast cancer patients harboring germline BRCA1/2 pathogenic variants. PATIENTS AND METHODS: This is a multicenter retrospective cohort study across 30 centers worldwide including women diagnosed at ≤40 years with stage I-III breast cancer, between January 2000 and December 2012, harboring known germline BRCA1/2 pathogenic variants. Patients included in this analysis had a post-treatment pregnancy either achieved through use of ART (ART group) or naturally (non-ART group). ART procedures included ovulation induction, ovarian stimulation for in vitro fertilization or intracytoplasmic sperm injection, and embryo transfer under hormonal replacement therapy. RESULTS: Among the 1424 patients registered in the study, 168 were eligible for inclusion in the present analysis, of whom 22 were in the ART group and 146 in the non-ART group. Survivors in the ART group conceived at an older age compared with those in the non-ART group (median age: 39.7 versus 35.4 years, respectively). Women in the ART group experienced more delivery complications compared with those in the non-ART group (22.1% versus 4.1%, respectively). No other apparent differences in obstetrical outcomes were observed between cohorts. The median follow-up from pregnancy was 3.4 years (range: 0.8-8.6 years) in the ART group and 5.0 years (range: 0.8-17.6 years) in the non-ART group. Two patients (9.1%) in the ART group experienced a disease-free survival event (specifically, a locoregional recurrence) compared with 40 patients (27.4%) in the non-ART group. In the ART group, no patients deceased compared with 10 patients (6.9%) in the non-ART group. CONCLUSION: This study provides encouraging safety data on the use of ART in breast cancer survivors harboring germline pathogenic variants in BRCA1/2, when natural conception fails or when they opt for ART in order to carry out preimplantation genetic testing.


Asunto(s)
Neoplasias de la Mama , Adulto , Proteína BRCA1/genética , Neoplasias de la Mama/genética , Femenino , Células Germinativas , Humanos , Recurrencia Local de Neoplasia/etiología , Embarazo , Técnicas Reproductivas Asistidas/efectos adversos , Estudios Retrospectivos
9.
Science ; 190(4217): 910-2, 1975 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-1242543

RESUMEN

The light mitochondrial fraction of hypoxic rodent kidneys, called the renal erythropoietic factor, contains erythropoietin in a pro, or active form. Erythropoietin is released from this inactive form when the renal erythropoietic factor is incubated with normal serum. The biogenesis of erythropoietin possibly involves a system in kidney reminiscent of the proinsulin-insulin system in pancreas.


Asunto(s)
Eritropoyetina/análogos & derivados , Eritropoyetina/biosíntesis , Eritropoyetina/metabolismo , Riñón/metabolismo , Precursores de Proteínas/metabolismo , Animales , Eritropoyetina/sangre , Femenino , Hipoxia/metabolismo , Riñón/ultraestructura , Ratones
10.
J Clin Invest ; 93(6): 2408-16, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8200975

RESUMEN

Platelet-activating factor (PAF) can exert profound inflammatory effects at very low concentrations. In plasma, PAF is hydrolyzed to lyso-PAF by acetylhydrolase, an enzyme that circulates bound to LDL. Previous studies suggest that oxygen radicals may act synergistically with PAF to potentiate tissue injury. However, mechanisms underlying this interaction have not been elucidated. In this study we investigated whether oxygen radicals may inactivate PAF acetylhydrolase. PAF acetylhydrolase activity was measured in human plasma and purified LDL before and after exposure to radicals (10-20 nmol/min per ml) generated by xanthine/xanthine oxidase. Oxygen radicals induced > 50% loss of PAF acetylhydrolase activity within 60 s and almost complete inactivation by 10 min. This phenomenon was irreversible and independent of oxidative modification of LDL. Inactivation occurred without changes in the affinity constant of the enzyme (Km was 17.9 microM under control conditions and 15.1 microM after exposure to oxygen radicals). Inactivation was prevented by the scavengers superoxide dismutase or dimethylthiourea or by the iron chelator deferoxamine. Thus, superoxide-mediated, iron-catalyzed formation of hydroxyl radicals can rapidly and irreversibly inactivate PAF acetylhydrolase. Since concomitant production of PAF and oxygen radicals can occur in various forms of tissue injury, inactivation of acetylhydrolase might represent one mechanism by which oxygen radicals may potentiate and prolong the proinflammatory effects of PAF.


Asunto(s)
Oxígeno/farmacología , Fosfolipasas A/antagonistas & inhibidores , Factor de Activación Plaquetaria/metabolismo , 1-Alquil-2-acetilglicerofosfocolina Esterasa , Radicales Libres , Humanos , Lipoproteínas LDL/metabolismo , Fosfolipasas A/sangre
11.
J Clin Invest ; 87(6): 2056-66, 1991 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1645750

RESUMEN

To test whether generation of oxygen radicals during postischemic reperfusion might promote peroxidation of cardiac membrane lipids, four groups of Langendorff-perfused rabbit hearts were processed at the end of (a) control perfusion, (b) 30 min of total global ischemia at 37 degrees C without reperfusion, (c) 30 min of ischemia followed by reperfusion with standard perfusate, (d) 30 min of ischemia followed by reperfusion with the oxygen radical scavenger human recombinant superoxide dismutase (h-SOD). The left ventricle was homogenized and tissue content of malonyldialdehyde (MDA), an end product of lipid peroxidation, was measured on the whole homogenate as well as on various subcellular fractions. Reperfusion was accompanied by a significant increase in MDA content of the whole homogenate and of the fraction enriched in mitochondria and lysosomes. This phenomenon was not observed in hearts subjected to ischemia but not reperfused, and was similarly absent in those hearts which received h-SOD at reflow. Reperfused hearts also had significantly greater levels of conjugated dienes (another marker of lipid peroxidation) in the mitochondrial-lysosomal fraction. Again, this phenomenon did not occur in ischemic hearts or in reperfused hearts treated with h-SOD. Unlike the effect on tissue MDA and conjugated dienes, reperfusion did not significantly stimulate release of MDA in the cardiac effluent. Treatment with h-SOD was also associated with significant improvement in the recovery of cardiac function. In conclusion, these data directly demonstrate that postischemic reperfusion results in enhanced lipid peroxidation of cardiac membranes, which can be blocked by h-SOD, and therefore is most likely secondary to oxygen radical generation at reflow.


Asunto(s)
Peróxidos Lipídicos/metabolismo , Lípidos de la Membrana/metabolismo , Miocardio/metabolismo , Oxígeno/toxicidad , Daño por Reperfusión/etiología , Acetilglucosaminidasa/metabolismo , Animales , Presión Sanguínea , Circulación Coronaria , Citosol/metabolismo , Complejo IV de Transporte de Electrones/metabolismo , Radicales Libres , Microsomas/metabolismo , Mitocondrias Cardíacas/metabolismo , Miocardio/ultraestructura , NADH Deshidrogenasa/metabolismo , Conejos , Flujo Sanguíneo Regional , Daño por Reperfusión/metabolismo , Sarcolema/metabolismo
12.
Circ Res ; 89(11): 991-6, 2001 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-11717155

RESUMEN

Maternal hypercholesterolemia during pregnancy is associated with enhanced fatty streak formation in human fetuses and faster progression of atherosclerosis during childhood even under normocholesterolemic conditions. A causal role of maternal hypercholesterolemia in lesion formation during fetal development has previously been established in rabbits. The same experimental model is now used to establish that maternal hypercholesterolemia or ensuing pathogenic events in fetal arteries enhance atherogenesis later in life. Five groups of rabbit mothers were fed chow, cholesterol-enriched chow, or cholesterol-enriched chow plus 1000 IU vitamin E, 3% cholestyramine, or both during pregnancy. Offspring of all groups (n=136) were fed a mildly hypercholesterolemic diet for up to a year and had similar cholesterol levels. Aortic lesion sizes and lipid peroxidation products in plasma and lesions in offspring were determined at birth, 6 months, or 12 months. Lesion progression in offspring of hypercholesterolemic mothers was greater than in all other groups. At each time point, offspring of hypercholesterolemic mothers had 1.5- to 3-fold larger lesions than offspring of normocholesterolemic mothers (P<0.01), with the greatest absolute differences at 12 months. Maternal treatment reduced lesions by 19% to 53%, compared with offspring of untreated hypercholesterolemic mothers (P<0.01), with the greatest effect in the vitamin E groups. At 12 months, lesions in offspring of all vitamin E and cholestyramine-treated mothers were similar to those of normocholesterolemic mothers. Lipid peroxidation end-products in lesions and plasma showed analogous differences between groups as lesions (P<0.01). Thus, pathogenic programming in utero increases the susceptibility to atherogenic risk factors later in life and maternal intervention with cholesterol-lowering drugs or antioxidants reduce postnatal lipid peroxidation and atherosclerosis in their offspring.


Asunto(s)
Arteriosclerosis/etiología , Hipercolesterolemia/tratamiento farmacológico , Animales , Anticolesterolemiantes/uso terapéutico , Antioxidantes/uso terapéutico , Aorta/patología , Enfermedades de la Aorta/sangre , Enfermedades de la Aorta/etiología , Enfermedades de la Aorta/patología , Arteriosclerosis/sangre , Arteriosclerosis/patología , Resina de Colestiramina/uso terapéutico , Progresión de la Enfermedad , Femenino , Ácido Linoleico/sangre , Peroxidación de Lípido , Malondialdehído/sangre , Embarazo , Conejos , Vitamina E/uso terapéutico
13.
Diabetes ; 24(3): 249-56, 1975 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1116648

RESUMEN

The influence of intraperitoneal administration of aminophylline on the rate of hepatic glucose production and peripheral uptake (Ra and Rd) was studied in normal and in adrenodemedullated and reserpinized rats by using the primed constant infusion of Glucose-2-3H. In normal rats, the dose of 100 mg. per kilogram of aminophylline produced a marked increase of Ra and Rd. Since Ra rose more rapidly than Rd did initially, hyperglycemia developed. Thereafter, glucose production and uptake increased to nearly the same extent, and a new steady state was reached at plasma glucose levels almost twice those of the baseline. Smaller and transient modifications were observed after the administration of 20 mg. per kilogram of aminophylline. With the higher dose, insulin levels markedly rose (reaching a tenfold peak above the basal value) while minor increments were observed with the lower dose. In a group of normal rats which were given glucose (10 mg. per kilogram per minute) in order to achieve a degree of hyperglycemia comparable to that brought about by the higher dose of aminophylline, an almost identical enhancement of glucose uptake was recorded. However, insulin levels were much higher in aminophylline-treated rats as compared to normal rats. From these finding it was concluded that aminophylline induces resistance to insulin effect. When aminophylline was injected into demedullated rats pretreated with reserpine, at the dose of 100 mg. per kilogram, a marked enhancement of Ra, and consequently of glycemia, was recorded initially; later, severe hypoglycemia developed depending on both a progressive exhaustion of hepatic glucose production and a marked increase of glucose utilization. Insulin levels dramatically increased in these experiments. These results suggest that aminophylline directly increases glucose production by the liver and insulin secretion. The simultaneous activation of the sympathetic system blunts the insulin response and counteracts the restraining effect of insulin on the liver and the stimulatory effect of insulin on overall glucose uptake as well.


Asunto(s)
Glucosa/metabolismo , Sistema Nervioso Simpático/fisiología , Teofilina/farmacología , Médula Suprarrenal/fisiología , Aminofilina/administración & dosificación , Aminofilina/farmacología , Animales , Glucemia/análisis , Glucosa/biosíntesis , Insulina/sangre , Insulina/metabolismo , Resistencia a la Insulina , Secreción de Insulina , Cinética , Hígado/metabolismo , Masculino , Tasa de Depuración Metabólica , Ratas , Simpatectomía , Teofilina/administración & dosificación
14.
J Am Coll Cardiol ; 26(6): 1411-6, 1995 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-7594063

RESUMEN

OBJECTIVES: The aim of this double-blind, placebo-controlled, dose titration, multicenter trial was to assess the efficacy and safety of propionyl-carnitine in intermittent claudication. BACKGROUND: Human and animal studies indicate that propionyl-L-carnitine increases carnitine content and improves energy metabolism in the ischemic skeletal muscle. METHODS: After a 2-week preliminary period to assess maximal walking distance, 245 patients were randomly assigned to receive propionyl-L-carnitine (n = 118) or placebo (n = 127). The initial oral dose of 500 mg twice daily was increased at 2-month intervals to 2 g/day and then to 3 g/day in patients showing improvement in treadmill performance < 30% over baseline. Efficacy analysis was conducted for the 214 patients who completed the 24 weeks of treatment by comparing the effect of placebo and propionyl-L-carnitine on day 180. RESULTS: Analysis of variance showed a significant improvement of 73 +/- 9% (mean +/- SE) in maximal walking distance with propionyl-L-carnitine (n = 99) compared with 46 +/- 6% for placebo (n = 115, p = 0.03). For distance walked at onset of claudication, propionyl-L-carnitine showed about double the improvement of placebo; however, the difference was not statistically significant. There were no changes in electrocardiographic and routine biochemical and hematologic tests that would indicate an adverse effect of propionyl-L-carnitine. Adverse events requiring drug discontinuation (11 in the propionyl-L-carnitine group, 3 in the placebo group) were unrelated to study medication. The dose titration design of the study also provided information on the dose-response relation. Slightly less than 67% of patients were expected to improve their maximal walking distance by at least 30%, assuming 2 g/day of propionyl-L-carnitine (95% confidence interval 0.51 to 0.70). The response rate during the entire titration course was significantly in favor of propionyl-L-carnitine compared with placebo. CONCLUSIONS: Although the precise mode of therapeutic action requires clarification, propionyl-L-carnitine, at a dose of 1 to 2 g/day, appears to be effective and well tolerated, with minimal adverse effects.


Asunto(s)
Cardiotónicos/administración & dosificación , Carnitina/análogos & derivados , Claudicación Intermitente/tratamiento farmacológico , Administración Oral , Análisis de Varianza , Cardiotónicos/efectos adversos , Carnitina/administración & dosificación , Carnitina/efectos adversos , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Esquema de Medicación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
15.
J Am Coll Cardiol ; 11(5): 944-52, 1988 May.
Artículo en Inglés | MEDLINE | ID: mdl-3356840

RESUMEN

To examine whether cardiopulmonary receptors participate in the reflex control of coronary vascular resistance, systemic and coronary hemodynamics were assessed before and during -10 mm Hg lower body negative pressure in eight normal subjects and eight hypertensive patients with left ventricular hypertrophy. In both study groups, lower body negative pressure induced a significant decrease in right atrial pressure, left ventricular filling pressure and cardiac output, an increase in systemic vascular resistance and no change in mean arterial pressure and heart rate. In normal subjects, there was also a significant increase in plasma norepinephrine concentration (from 294 +/- 39 to 421 +/- 47 pg/ml, p less than 0.01). This increase was accompanied by a reduction in coronary blood flow, assessed by the continuous thermodilution method (from 101 +/- 5 to 79 +/- 4 ml/min, p less than 0.05). An increase in coronary vascular resistance (from 0.865 +/- 0.1 to 1.107 +/- 0.1 mm Hg/ml per min, p less than 0.05) and in myocardial oxygen consumption was detected in normal subjects during cardiopulmonary baroreceptor unloading. In contrast, in hypertensive patients, -10 mm Hg lower body negative pressure failed to induce any change in plasma norepinephrine, coronary blood flow or vascular resistance. Intravenous propranolol administration caused no significant change in the systemic hemodynamic response to -10 mm Hg lower body negative pressure in either study group, but it did abolish the decrease in coronary flow and the increase in plasma norepinephrine, coronary vascular resistance and myocardial oxygen consumption observed in normal subjects in control conditions.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Vasos Coronarios/inervación , Hipertensión/fisiopatología , Presorreceptores/fisiología , Reflejo/fisiología , Resistencia Vascular , Adulto , Vías Aferentes/fisiopatología , Presión Sanguínea/efectos de los fármacos , Cardiomiopatía Hipertrófica/sangre , Cardiomiopatía Hipertrófica/complicaciones , Cardiomiopatía Hipertrófica/fisiopatología , Arterias Carótidas/inervación , Circulación Coronaria/efectos de los fármacos , Femenino , Hemodinámica/efectos de los fármacos , Humanos , Hipertensión/sangre , Hipertensión/complicaciones , Masculino , Norepinefrina/sangre , Consumo de Oxígeno/efectos de los fármacos , Presorreceptores/efectos de los fármacos , Propranolol/farmacología , Sistema Nervioso Simpático/fisiopatología , Transductores de Presión , Resistencia Vascular/efectos de los fármacos , Vasoconstricción/efectos de los fármacos
16.
J Am Coll Cardiol ; 20(3): 587-93, 1992 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1512337

RESUMEN

BACKGROUND: Baroreflex sensitivity provides useful prognostic information in patients after acute myocardial infarction. However, no data are available about the effects of converting enzyme inhibition on this variable. OBJECTIVES: The aim of the study was to evaluate the effects of angiotensin-converting enzyme inhibition on baroreflex sensitivity in patients after uncomplicated myocardial infarction. METHODS: Twenty-five patients after uncomplicated myocardial infarction underwent baroreflex sensitivity evaluation 72 to 96 h after symptom onset and after 4 days of captopril therapy. Twenty additional patients with the same characteristics were evaluated at the same time intervals before and after placebo administration to identify spontaneous baroreflex sensitivity variations. Baroreflex sensitivity was assessed by calculating the regression line relating phenylephrine-induced increases in systolic blood pressure to the attendant changes in the RR interval. RESULTS: The mean baroreflex sensitivity value increased after captopril administration from 6.5 +/- 4.2 to 11.8 +/- 6.1 ms/mm Hg (p less than 0.01) and in individual analyses increased by greater than 2 ms/mm Hg in 68% of patients. Mean plasma renin activity increased after captopril from 3.7 +/- 2.4 to 8.5 +/- 4.9 ng/ml per h (p less than 0.005). No difference was detectable in baroreflex sensitivity and plasma renin activity values according to the site of necrosis. In the control group, baroreflex sensitivity and plasma renin activity remained unchanged between the two studies. CONCLUSIONS: This study demonstrates that in patients with uncomplicated myocardial infarction, captopril significantly improves the chronotropic response to baroreceptor stimulation.


Asunto(s)
Captopril/farmacología , Infarto del Miocardio/fisiopatología , Presorreceptores/efectos de los fármacos , Reflejo/efectos de los fármacos , Adulto , Anciano , Presión Sanguínea/efectos de los fármacos , Electrocardiografía/efectos de los fármacos , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/sangre , Fenilefrina/farmacología , Renina/sangre
17.
J Am Coll Cardiol ; 5(6): 1312-8, 1985 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3998314

RESUMEN

Systemic and coronary hemodynamics were assessed before and during a reduction in carotid transmural pressure. This reduction was induced by means of a pneumatic neck chamber in 15 normal subjects and 15 hypertensive patients with a normal coronary arteriogram. A reduced baroreflex responsiveness was demonstrated in hypertensive patients as compared with normal subjects by evaluating both the reflex bradycardia evoked by intravenous administration of phenylephrine and the reflex increase in blood pressure during carotid sinus hypotension. In normal subjects, the reduction in carotid transmural pressure induced a significant increase in mean blood pressure, total peripheral resistance, cardiac output, heart rate, coronary vascular resistance, coronary blood flow assessed by the continuous thermodilution method and myocardial oxygen consumption. In hypertensive patients, the same stimulus significantly increased mean blood pressure, cardiac output, heart rate and coronary blood flow while no significant change was detected in coronary vascular resistance and myocardial oxygen consumption. The increase in mean blood pressure, total peripheral resistance and cardiac output was significantly higher in normal subjects than in hypertensive patients. These results suggest that in normal subjects carotid sinus hypotension evokes reflex coronary vasoconstriction, whereas this response is blunted in hypertensive patients with reduced baroreflex sensitivity.


Asunto(s)
Seno Carotídeo/fisiología , Circulación Coronaria , Presorreceptores/fisiología , Reflejo/fisiología , Adulto , Presión Sanguínea , Gasto Cardíaco , Seno Carotídeo/efectos de los fármacos , Femenino , Frecuencia Cardíaca , Humanos , Hipertensión/fisiopatología , Masculino , Miocardio/metabolismo , Consumo de Oxígeno , Fenilefrina/farmacología , Presorreceptores/efectos de los fármacos , Reflejo/efectos de los fármacos , Termodilución , Resistencia Vascular , Vasoconstricción
18.
J Am Coll Cardiol ; 23(1): 27-34, 1994 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8277091

RESUMEN

OBJECTIVES: This study was conducted to assess the efficacy of sulodexide, a glycosaminoglycan compound with antithrombotic properties, in preventing death and thromboembolic events after acute myocardial infarction. BACKGROUND: Antithrombotic therapy has been found to play an important role in the prevention of cardiovascular events and death after acute myocardial infarction. Glycosaminoglycan-containing compounds, including sulodexide, show profibrinolytic and antithrombotic properties that render them suitable for use in patients after infarction. METHODS: A total of 3,986 patients who had recovered from acute myocardial infarction were randomized to receive either the standard therapy routinely administered at each study center, excluding antiplatelet and anticoagulant drugs (control group, 1,970 patients), or the standard therapy plus sulodexide (treated group, 2,016 patients). Between 7 and 10 days after the episode of acute myocardial infarction, sulodexide was administered as a single daily 600-lipoprotein-lipase-releasing unit (LRU) intramuscular injection for the 1st month, followed by oral capsules of 500 LRU twice daily. Patients were evaluated for > or = 12 months. RESULTS: At the end of the study, 140 deaths (7.1%) were recorded in the control group and 97 (4.8%) in the sulodexide group (32% risk reduction, p = 0.0022, chi-square test). A total of 90 patients (4.6%) in the control group had a further infarction, compared with 66 (3.3%) in the sulodexide group (28% risk reduction, p = 0.035). Furthermore, a reduction in left ventricular thrombus formation (evaluated by echocardiography) was observed in the sulodexide group (n = 12; 0.6%), compared with values in the control group (n = 25; 1.3%) (53% risk reduction, p = 0.027). Sulodexide was well tolerated and devoid of significant adverse events. All significant results were confirmed by "actual treatment" analyses. CONCLUSIONS: The study provides evidence that long-term therapy with sulodexide started early after an episode of acute myocardial infarction is associated with reductions in total mortality, rate of reinfarction and mural thrombus formation.


Asunto(s)
Glicosaminoglicanos/uso terapéutico , Hipolipemiantes/uso terapéutico , Infarto del Miocardio/tratamiento farmacológico , Infarto del Miocardio/mortalidad , Terapia Trombolítica , Anciano , Enfermedades Cardiovasculares/prevención & control , Causas de Muerte , Femenino , Cardiopatías/prevención & control , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/fisiopatología , Estudios Prospectivos , Recurrencia , Trombosis/prevención & control , Factores de Tiempo
19.
J Am Coll Cardiol ; 10(4): 787-93, 1987 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2958531

RESUMEN

Hemodynamic and hormonal effects of two graded infusions of alpha-human-(1-28)-atrial natriuretic factor (0.5 microgram/kg prime followed by 0.05 microgram/kg per min for 20 minutes and by 0.1 microgram/kg per min for 20 minutes) were evaluated in 13 patients with mild to moderate essential hypertension. The lower dose of atrial natriuretic factor did not change significantly any of the considered variables, although it tended to reduce aortic mean blood pressure (from 132.6 +/- 5.3 to 125.5 +/- 4.6 mm Hg), cardiac index (from 3.67 +/- 0.2 to 3.54 +/- 0.18 liters/min per m2) and forearm vascular resistance (from 178.6 +/- 15 to 148.3 +/- 10 mm Hg/ml per s). The higher dose of atrial natriuretic factor significantly reduced mean aortic pressure (118.6 +/- 5 mm Hg), cardiac index (3.29 +/- 0.16 liters/min per m2) and stroke volume index (from 45.9 +/- 2.6 to 38.9 +/- 3 ml/m2) and slightly decreased pulmonary wedge pressure, whereas both total peripheral resistance and forearm vascular resistance were not modified. With this latter dose a reduction in aortic pressure was observed in all patients at the steady state, and this was associated with a fall in stroke volume index in 10 of the 13 patients and with a reduction in total peripheral resistance in only 6 patients. Heart rate and right atrial and pulmonary pressures did not change during infusion of atrial natriuretic factor. Plasma renin activity was only slightly reduced by atrial natriuretic factor, whereas plasma norepinephrine rose significantly (from 233 +/- 34 to 330 +/- 58 pg/ml).(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Factor Natriurético Atrial/farmacología , Hemodinámica/efectos de los fármacos , Hipertensión/sangre , Adulto , Aldosterona/sangre , Factor Natriurético Atrial/efectos adversos , Epinefrina/sangre , Femenino , Humanos , Hipertensión/fisiopatología , Masculino , Persona de Mediana Edad , Norepinefrina/sangre , Renina/sangre
20.
J Am Coll Cardiol ; 21(2): 493-501, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8426016

RESUMEN

OBJECTIVES: The aim of this study was to assess whether prostaglandin endoperoxides, which continue to be formed in the setting of thromboxane A2 synthase inhibition, might influence the fate of ischemic myocardium in a model of coronary occlusion and reperfusion. BACKGROUND: It was recently demonstrated that thromboxane A2 synthase inhibitors reduce ischemic myocardial injury through a redirection of prostaglandin (PG) endoperoxides toward the synthesis of "cardioprotective" prostaglandins, such as PGI2, PGE2 and PGD2. However, part of these prostaglandin endoperoxides may also stimulate a receptor, shared with thromboxane A2, mediating platelet aggregation and vasoconstriction. METHODS: New Zealand White rabbits were subjected to 30 min of coronary occlusion, followed by 5.5 h of reperfusion. Fifteen minutes before reperfusion, the animals were randomized to receive 1) saline solution (control animals, n = 8); 2) SQ 29548, a potent and selective thromboxane A2/PGH2 receptor antagonist (n = 8); 3) dazoxiben, a selective thromboxane A2 synthase inhibitor (n = 8); 4) R 68070 (Ridogrel), a drug with dual thromboxane A2 synthase-inhibiting and thromboxane A2/PGH2 receptor-blocking properties (n = 8); or 5) aspirin + R 68070 (n = 8). RESULTS: Dazoxiben and R 68070, but not SQ 29548, significantly reduced thromboxane B2 formation and increased plasma levels of 6-keto-PGF1 alpha, PGE2 and PGF2 alpha. Ex vivo platelet aggregation induced by U46619 (a thromboxane A2 mimetic) was inhibited by SQ 29548 and R 68070 but not by dazoxiben. In control animals, infarct size determined at the end of the experiment by triphenyltetrazolium chloride staining averaged 57.7 +/- 3.2% of the area at risk of infarction. The administration of SQ 29548 did not significantly reduce infarct size compared with that in control animals, whereas dazoxiben and R 68070 significantly reduced infarct size to 36.7 +/- 2.8% and 16.6 +/- 3.6% of area at risk of infarction, respectively (p < 0.001 vs. control values). In rabbits treated with R 68070, infarct size was also significantly smaller than that of dazoxiben-treated rabbits (p < 0.01). This protective effect of R 68070 was completely abolished when the drug was administered with aspirin, infarct size in this group averaging 59.7 +/- 1.6% (p = NS vs. control values). No differences in regional myocardial blood flow, systemic blood pressure, heart rate or extent of area at risk were observed among groups. CONCLUSIONS: Thus, prostaglandin endoperoxides play an important role in modulating the cardioprotective effects of thromboxane A2 synthase inhibitors. The simultaneous inhibition of thromboxane A2 synthase and blockade of thromboxane A2/PGH2 receptors by R 68070 identify a pharmacologic interaction of potential therapeutic importance.


Asunto(s)
Infarto del Miocardio/fisiopatología , Daño por Reperfusión Miocárdica/prevención & control , Endoperóxidos de Prostaglandina/fisiología , Receptores de Tromboxanos/antagonistas & inhibidores , Tromboxano-A Sintasa/antagonistas & inhibidores , Animales , Aspirina/farmacología , Compuestos Bicíclicos Heterocíclicos con Puentes , Ácidos Grasos Insaturados , Femenino , Hidrazinas/farmacología , Imidazoles/farmacología , Masculino , Infarto del Miocardio/prevención & control , Daño por Reperfusión Miocárdica/fisiopatología , Ácidos Pentanoicos/farmacología , Agregación Plaquetaria/efectos de los fármacos , Endoperóxidos de Prostaglandinas Sintéticos/farmacología , Piridinas/farmacología , Conejos
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