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1.
Cytopathology ; 29(1): 41-48, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29063636

RESUMEN

OBJECTIVE: As of 2017, the pathobiology of gastric cancer (GC) is far from fully understood; consequently, new methods of basic and advanced research have been proposed and tested. The presence (GL1) vs absence (GL0) of malignant cells exfoliated in gastric lavage (GL) of GC patients was formerly evaluated with diagnostic intent but not for staging or prognostic assessment. We investigated this hitherto unreported application of cytopathology. METHODS: GL was preoperatively and prospectively collected from 80 GC patients and cytologically analysed. The results were compared with the classic clinicopathological features of GC and related to survival. The prognostic value of GL1 was assessed through univariate and multivariate analyses. RESULTS: GL1 was detected in 36 samples (45%) and correlated with advanced tumour depth (T3-T4), lymphatic metastasis (N+), distant metastasis (M1) and lymphovascular invasion (LVI1; P=.0317, .0024, .003 and .0028, respectively). Overall survival (OS) was significantly shorter for GL1 (23 months) vs GL0 patients (42 months; P=.005) and GL1 vs GL0 T1 subjects (12.6 vs 47.8 months, P=.0029). Univariate analysis revealed that GL1, N+, M1, LVI1 and advanced stage were significantly associated with OS. Multivariate analysis assessed GL1 as the only independent prognostic factor for worse OS and progression-free survival (P=.0013 and .0107). CONCLUSIONS: In the present study, GL1 was correlated with advanced disease, aggressive tumour behaviour and poor prognosis. Although additional studies are needed to confirm these findings, the GL0/GL1 classification can be applied to GC patients to achieve higher accuracy in staging, prognostic stratification and treatment selection.


Asunto(s)
Adenocarcinoma/clasificación , Adenocarcinoma/patología , Estadificación de Neoplasias/métodos , Neoplasias Gástricas/clasificación , Neoplasias Gástricas/patología , Adenocarcinoma/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Supervivencia sin Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Fenotipo , Pronóstico , Modelos de Riesgos Proporcionales , Neoplasias Gástricas/diagnóstico , Irrigación Terapéutica
2.
Nutr Metab Cardiovasc Dis ; 27(2): 115-120, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27745933

RESUMEN

AIM: The aim of this study is to discuss the reliable scientific evidence of an interactive link between hypertension and hypercholesterolemia considering the metabolic pathways and the pathogenetic mechanisms connecting the two risk factors. DATA SYNTHESIS: Hypertension and hypercholesterolemia are highly prevalent in the general population and their coexistence in the same subjects additively increases the risk of cardiovascular disease. Probably, hypercholesterolemia is also a risk factor for the development of hypertension. On the other side, it is also possible that lipid-lowering treatment could improve blood pressure control. Although the mechanisms of interaction between these two risk factors have not been completely elucidated thus far, there is rapidly growing evidence that the involvement of the renin-angiotensin system (RAS) can be considered as the common link between hypertension and hypercholesterolemia. In particular, hypercholesterolemia seems to promote the upregulation of type 1 angiotensin II (AT1) receptor genes because of an increase in the stability of mRNA followed by structural overexpression of vascular AT1 receptors for angiotensin II. The treatment of both risk factors greatly improves individual risk profile, especially when statins and RAS blockers are used together. CONCLUSIONS: Hypertension and hypercholesterolemia are highly coprevalent and strongly related from a pathophysiological point of view. The RAS could be the main mediator of this link.


Asunto(s)
Presión Sanguínea , Colesterol/sangre , Hipercolesterolemia/fisiopatología , Hipertensión/fisiopatología , Sistema Renina-Angiotensina , Bloqueadores del Receptor Tipo 1 de Angiotensina II/uso terapéutico , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Antihipertensivos/uso terapéutico , Biomarcadores/sangre , Presión Sanguínea/efectos de los fármacos , Comorbilidad , Humanos , Hipercolesterolemia/sangre , Hipercolesterolemia/tratamiento farmacológico , Hipercolesterolemia/epidemiología , Hipertensión/tratamiento farmacológico , Hipertensión/epidemiología , Hipolipemiantes/uso terapéutico , Prevalencia , Receptor de Angiotensina Tipo 1/genética , Receptor de Angiotensina Tipo 1/metabolismo , Sistema Renina-Angiotensina/efectos de los fármacos , Medición de Riesgo , Factores de Riesgo
3.
Nutr Metab Cardiovasc Dis ; 22(5): 442-8, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-21193292

RESUMEN

BACKGROUND AND AIMS: In the field of cardiovascular diseases, elevated levels of serum uric acid (UA) reflect a marked activation of the xanthine oxidase pathway with increase in free radicals production; it is often associated with an inflammatory state, oxygen consumption and endothelial dysfunction. All these associations have been also confirmed in heart failure (HF) but the pathophysiological role of UA in this setting is not well understood. The aim of this study was to evaluate the prognostic role of UA in outpatients enrolled in the Italian Registry of Congestive Heart Failure (IN-CHF). METHODS AND RESULTS: All patients met the European Society of Cardiology (ESC) criteria for diagnosis of HF. We considered patients with complete clinical data and UA level available at the baseline and at 1-year follow-up. The study population was composed of 877 patients aged 63 ± 12 years. One-year mortality was 10.8% and dead patients had a higher level of UA than survivors (7.1 mg dl⁻¹ vs 6.6 mg dl⁻¹, p < 0.0207). In multivariable full model of analysis, UA did not result in an independent predictor of death in overall population, but only in patients with low body mass index (BMI) (≤22 kg m⁻²) (hazard ratio (HR): 2.38, 95% confidence interval (CI) 1.36-4.18). In this subgroup, a statistically significant gradual relationship between UA and survival was detected starting from values higher than 8 mg dl⁻¹. CONCLUSION: Elevated level of UA is not an independent predictor of mortality in chronic HF, but it markedly worsens outcome if associated with low level of BMI. This association is likely an indicator of chronic inflammatory and catabolic state.


Asunto(s)
Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/diagnóstico , Hiperuricemia/complicaciones , Hiperuricemia/etiología , Delgadez/complicaciones , Ácido Úrico/sangre , Anciano , Anciano de 80 o más Años , Atención Ambulatoria , Índice de Masa Corporal , Femenino , Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/fisiopatología , Humanos , Hiperuricemia/fisiopatología , Italia/epidemiología , Masculino , Persona de Mediana Edad , Modelos Biológicos , Mortalidad , Pronóstico , Sistema de Registros , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Análisis de Supervivencia
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 219: 288-296, 2019 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-31051423

RESUMEN

We present a novel experimental study on solid CH2DOH pure and in astrophysical relevant mixtures. Solid samples were accreted under ultra high vacuum conditions at 17 K and were analyzed by mid-infrared transmission spectroscopy. Refractive index, density, and mid-IR band strength values were measured for pure solid CH2DOH. The refractive index was also measured for CH2DOH:H2O, CH2DOH:CO, and CH2DOH:CH3OH mixtures. For all samples, the thermal evolution of the main band profile was studied. We used the interference laser technique (HeNe laser, λ = 543.5 nm) to measure the samples thickness and a numerical method to measure the refractive index starting from the amplitude of the interference curve. We obtained the ice density through the Lorentz-Lorenz relation. To calculate the band strength values we used the linear fit of the integrated band intensities with respect to the column densities. Samples deposited at 17 K were warmed up to their sublimation temperature. Spectra were taken at selected temperatures to study their thermal evolution. The results are discussed in view of their relevance for the interpretation of astronomical IR spectra.

5.
Oncol Rep ; 18(4): 793-800, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17786338

RESUMEN

In oral squamous cell carcinomas of the head and neck, Laminin-5 gamma2 has been associated with tissue invasion, lymph node metastasis and histopathological grading. In the present study, we compared the expression of the subunit gamma2 of Laminin-5 under normal, dysplastic and invading epithelia in 65 biopsies previously diagnosed for oral squamous cell carcinoma. The number of gamma2-positive cells were analyzed in relation to patients' survival, tumor grading, size of the lesion, TNM stage, histopathological pattern of invasion and inflammatory reaction. Biopsies of oral squamous cell carcinomas were deparaffinised, processed for antigen unmasking procedures and stained with antibody anti-Laminin-5 gamma2. By light microscopy, 4 optical fields of x200 were selected in three different areas including normal, dysplastic and invading epithelia. Positive cells were counted and divided into three categories, which included <20 cells, between 21 and 50 cells and >50 stained cells. Patient survival was analyzed by Kaplan-Mayer curves. gamma2-positive cells were found in the basal layer of dysplastic epithelium, within inflammatory infiltrate, at the margins of differentiated invading islands and at the forefront of undifferentiated invading nests. Observations showed that an increased number of gamma2-positive cells correlated significantly with a shorter life expectancy under invading epithelia (log-rank test p<0.05), not when a count was performed under normal or dysplastic epithelia of the same patient. The number of gamma2-positive cells also correlated with the histopathological pattern of invasion. Our results show that gamma2 may be a reliable prognostic tool for oral squamous cell carcinomas.


Asunto(s)
Carcinoma de Células Escamosas/metabolismo , Laminina/metabolismo , Neoplasias de la Boca/metabolismo , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/patología , Humanos , Técnicas para Inmunoenzimas , Neoplasias de la Boca/mortalidad , Neoplasias de la Boca/patología , Invasividad Neoplásica/patología , Estadificación de Neoplasias , Pronóstico , Tasa de Supervivencia
6.
Eur Rev Med Pharmacol Sci ; 11(6): 413-7, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18306910

RESUMEN

A pharmacokinetic-pharmacodynamic (PK-PD) model was developed to simulate the plasma profile and the toxicity of vinorelbine after multiple oral dose treatment to humans. The PK drug profile was described by a three-compartment open model linked to a PD model aimed to describe the drug toxicity on the circulating neutrophils. Different dose schedules were simulated holding the total administered dose constant (100 mg p.o. during two weeks): 7.7 mg daily (13 doses), 20 mg every 3 days (5 doses) and 33.3 mg every 6 days (3 doses). The lowest values of the circulating neutrophils were observed after 18 days from the start of the treatment and at nadir the fraction of the circulating neutrophils were 0.733, 0.703 and 0.681 after the three doses in decreasing order. These differences were not clinically significant, however the drug bioavailability, which was fixed to 0.35 in the simulation, might be highly variable among subjects contributing to a large extent to the observed variability in drug toxicity.


Asunto(s)
Antineoplásicos Fitogénicos/efectos adversos , Neutropenia/inducido químicamente , Neutrófilos/efectos de los fármacos , Vinblastina/análogos & derivados , Antineoplásicos Fitogénicos/farmacocinética , Área Bajo la Curva , Disponibilidad Biológica , Esquema de Medicación , Humanos , Modelos Biológicos , Neutrófilos/metabolismo , Factores de Tiempo , Vinblastina/efectos adversos , Vinblastina/farmacocinética , Vinorelbina
7.
Cancer Res ; 46(5): 2566-71, 1986 May.
Artículo en Inglés | MEDLINE | ID: mdl-3697995

RESUMEN

Etoposide (VP16) pharmacokinetics was investigated in three groups of cancer patients: a control group of 18 patients with renal and hepatic function tests in the normal range; a group of 8 patients with renal insufficiency; and a group of 15 patients with abnormal hepatic function. In the control group plasma clearance (Clp), volume of distribution (Vd), and elimination half-life (t1/2 beta) of VP16 were, respectively, 22.8 +/- 1.0 (SE) ml/min/m2, 11.4 +/- 0.8 liters/m2, and 5.6 +/- 0.4 h. In patients with renal insufficiency Clp was 12.8 +/- 1.1 ml/min/m2, Vd was 20.8 +/- 4.9 liters/m2, and t1/2 beta was 19.2 +/- 4.7 h. A statistically significant correlation (P = 0.0000001) was found between VP16 Clp and creatinine clearance. In 12 of 15 patients with abnormal liver tests Clp, Vd, and t1/2 beta were, respectively, 27.9 +/- 2.7 ml/min/m2, 12.4 +/- 1.5 liters/m2, and 5.4 +/- 0.6 h and are thus similar to those of the control group. In the other three cases with abnormal liver function VP16 plasma levels were very low. In these cases VP16 t1/2 beta values were similar (5.1, 4.4, and 5.1 h) whereas Clp values (320, 87, and 96 ml/min/m2) and Vd values (142, 33, and 42 liters/m2) were much larger than in controls. These results suggest that VP16 doses should be reduced in patients with renal function impairment but not necessarily in patients with liver impairment. The high VP16 Vd and Clp values found in a subset of patients with liver impairment require further elucidation.


Asunto(s)
Etopósido/metabolismo , Enfermedades Renales/metabolismo , Hepatopatías/metabolismo , Podofilotoxina/análogos & derivados , Adulto , Anciano , Femenino , Humanos , Masculino , Tasa de Depuración Metabólica , Persona de Mediana Edad
8.
Aliment Pharmacol Ther ; 22(4): 343-8, 2005 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-16098001

RESUMEN

BACKGROUND: Acid suppression plus two antibiotics is currently considered the gold standard anti-Helicobacter pylori treatment, but the effective role of gastric antisecretory drugs is still poorly understood. AIMS: To compare a 14-day ranitidine-based triple regimen against Helicobacter pylori with one based on omeprazole, and to study the influence of antisecretory drugs on metronidazole pharmacokinetics in human plasma. METHODS: A total of 150 dyspeptic H. pylori-infected patients were randomized for ranitidine 300 mg b.d. (RCM group) or omeprazole 20 mg b.d. (OCM group) 14-day triple therapy, with clarithromycin 500 mg b.d. and metronidazole 500 mg b.d. On the eighth day of therapy, metronidazole pharmacokinetics was studied in plasma by high-performance liquid chromatography. The pharmacokinetic parameters (terminal half-life, area under the curve, peak-plasma level, peak time) of metronidazole were computed using standard non-compartmental methods. H. pylori status was monitored before and 4 weeks after the end of therapy by histology, serology and rapid urease test. RESULTS: On an intention-to-treat basis, eradication rates were 91 and 76% for the RCM and OCM groups respectively (P < 0.02). Significantly different pharmacokinetic parameters of metronidazole were found between the groups: peak-plasma level (P < 0.01) and area under the curve (P < 0.02). CONCLUSION: Our results show that the RCM regimen was more effective than that based on OCM and that the antisecretory drugs affected metronidazole availability, increasing the efficacy of ranitidine-based regimens.


Asunto(s)
Antiulcerosos/administración & dosificación , Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori , Omeprazol/administración & dosificación , Ranitidina/administración & dosificación , Adolescente , Adulto , Anciano , Antibacterianos/administración & dosificación , Antiinfecciosos/administración & dosificación , Antiinfecciosos/farmacocinética , Cromatografía Líquida de Alta Presión , Claritromicina/administración & dosificación , Quimioterapia Combinada/administración & dosificación , Femenino , Infecciones por Helicobacter/metabolismo , Humanos , Cuidados a Largo Plazo , Masculino , Metronidazol/administración & dosificación , Metronidazol/farmacocinética , Persona de Mediana Edad , Estudios Prospectivos , Resultado del Tratamiento
9.
J Chemother ; 17(6): 668-73, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16433199

RESUMEN

Over the last few years surgery on patients with abdominal malignancies has become more aggressive but the majority of patients present locoregional recurrence as peritoneal dissemination. Cytoreductive surgery followed by intraperitoneal chemohyperthermic perfusion (ICHP) has been described for treatment and prevention of locoregional cancer spread from various origins. This paper reports our study of the pharmacokinetics of mitomycin C (MMC) administered by intraperitoneal chemohyperthermic perfusion (ICHP) in patients with peritoneal carcinomatosis. 28 patients received MMC 20 mg/m2 intraperitoneally as a perfusion over 60 min. MMC was determined in perfusate, plasma and urine samples with a UV-HPLC method. A compartmental model was used to fit the drug concentrations in plasma and perfusate. Our results showed a mean maximum plasma concentration (Cmax) of 0.14 +/- 0.086 microg/ml with a peak time (Tmax) of 48..7 +/- 5.61 min. The mean area under the curve (AUC) and terminal half-life (t1/2) were 15.8 +/- 9.8 mg x min/L and 83.7 +/- 31.74 min respectively. Clearance (CL) was estimated by fitting the data by a compartmental model and the mean value was 72 +/- 66 L/h. The percent of the dose absorbed was very variable and ranged between 14 and 57% (mean 37 +/- 14%). The mean percentage of dose recovered unchanged in the urine during 24 hours was 7.21 +/- 3.73%. We conclude that ICHP in patients with peritoneal surface malignancies seems to have clinical value since it gives high peritoneal and tumor MMC concentrations with limited systemic exposure and toxicity.


Asunto(s)
Antibióticos Antineoplásicos/farmacocinética , Mitomicina/farmacocinética , Neoplasias Peritoneales/metabolismo , Adulto , Anciano , Antibióticos Antineoplásicos/uso terapéutico , Área Bajo la Curva , Quimioterapia del Cáncer por Perfusión Regional , Terapia Combinada , Femenino , Semivida , Humanos , Hipotermia Inducida , Infusiones Parenterales , Masculino , Tasa de Depuración Metabólica , Persona de Mediana Edad , Mitomicina/uso terapéutico , Invasividad Neoplásica , Neoplasias Peritoneales/patología , Neoplasias Peritoneales/terapia
10.
Endocrinology ; 129(1): 11-6, 1991 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1675985

RESUMEN

A major role for Ca2+ and calmodulin in stimulus-secretion coupling has been suggested for several neuropeptides; however, the cellular mechanisms of GH-releasing hormone (GHRH) release have been little investigated so far. We have used a previously validated acute rat hypothalamic explant system in order to elucidate whether Ca2+ acts as a second messenger in the regulation of GHRH release, and whether calmodulin-dependent pathways are involved. Calcium dependence of somatostatin (SRIH) release was assessed in the same experiments. Calmodulin dependence of SRIH was not investigated in detail, as it has been established previously. The calcium-entry antagonist, verapamil, antagonized K(+)-stimulated GHRH and SRIH release in a dose-dependent manner, with maximal inhibition shown at 10(-4) M. The calmodulin antagonist W7 also blocked K(+)-evoked GHRH release in a dose-dependent manner, with significant inhibition in the dose range 5 X 10(-5) M to 2 X 10(-4) M; similarly, a more specific calmodulin inhibitor, the W7 derivative 5-iodo-C8 (W8), reversed K(+)-stimulated GHRH release, showing slightly higher potency than W7. W7 also reversed GHRH release in response to the calcium-ionophore A23187, although verapamil had no effect on A23187-evoked GHRH or SRIH release. Thapsigargin, which increases the efflux of Ca2+ from calciosomes, did not affect either GHRH or SRIH release at 10(-5) M or 10(-4) M. The basal release of GHRH was clearly suppressed by W7 and W8 (10(-4) M), whereas verapamil had no effect. We conclude that calcium influx is crucial for depolarization-induced GHRH and SRIH release. Calcium entrance in response to A23187 appears to be independent of verapamil-sensitive calcium channels. The lack of effect of thapsigargin suggests that increased intracellular Ca2+ from intracellular stores is not equivalent to an increase in Ca2+ influx. Both basal and depolarization-induced release of GHRH in this system are calmodulin dependent.


Asunto(s)
Calcio/farmacología , Calmodulina/farmacología , Hormona Liberadora de Hormona del Crecimiento/metabolismo , Hipotálamo/metabolismo , Animales , Calcimicina/farmacología , Calmodulina/antagonistas & inhibidores , Hipotálamo/efectos de los fármacos , Técnicas In Vitro , Masculino , Potasio/farmacología , Ratas , Ratas Endogámicas , Somatostatina/metabolismo , Sulfonamidas/farmacología , Terpenos/farmacología , Tapsigargina , Verapamilo/farmacología
11.
Endocrinology ; 111(2): 693-5, 1982 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7094889

RESUMEN

The effect of sauvagine (SAU), a frog skin peptide, on prolactin (PRL) levels was studied in vivo and in vitro. Subcutaneous administration of SAU (20 micrograms/kg) reduced plasma PRL levels in normal adult male rats and suppressed the suckling-induced rise of PRL in lactating rats even at doses of 1 and 5 micrograms/kg. Perfusion of isolated and dispersed rat pituitary cells in vitro with increasing doses of SAU (from 5 x 10(-10) to 1.7 x 10(-8)M) induced a significant dose-related decrease of PRL secretion in the eluate. These results indicate that SAU is a potent PRL inhibiting factor and that its action is exerted at the pituitary level. If SAU or a SAU-related peptide is present in the mammalian brain, it can be tentatively hypothesized that this peptide plays an important role in the control of PRL secretion.


Asunto(s)
Péptidos/farmacología , Prolactina/antagonistas & inhibidores , Proteínas Anfibias , Animales , Bromocriptina/farmacología , Dopamina/farmacología , Relación Dosis-Respuesta a Droga , Masculino , Hormonas Peptídicas , Perfusión , Adenohipófisis/efectos de los fármacos , Adenohipófisis/metabolismo , Ratas , Ratas Endogámicas , Factores de Tiempo
12.
Endocrinology ; 129(3): 1275-82, 1991 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1678697

RESUMEN

There is clear evidence for communication between the immune and neuroendocrine systems. However, the effect of cytokines as major immune mediators on the hypothalamic growth peptides, GHRH and somatostatin (SRIH), is not well established. To investigate a possible hypothalamic action of the cytokines interleukin-1 beta (IL-1), interleukin-6, and tumor necrosis factor-alpha, on the release of GHRH and SRIH, we used a previously validated acute rat hypothalamic explant system. IL-1 caused a pronounced dose-dependent stimulation of SRIH in the dose-range 1-100 U/ml (P less than 0.01). GHRH showed a slight, but significant, increase in response to IL-1 tested in the dose-range 10-100 U/ml. Similar studies with mediobasal hypothalamic (GHRH and SRIH) or median eminence (SRIH) fragments produced no change in either GHRH or SRIH release. The effects of IL-1 were antagonized by the cyclo-oxygenase inhibitor, indomethacin (10 micrograms/ml). Stimulation of GHRH and SRIH could not be blocked by the CRH-antagonist alpha-helical CRH (9-41) at 10(-6) M. Interleukin-6, in the dose range 10-100 U/ml, and tumor necrosis factor-alpha, in the dose range 10-10,000 U/ml, had no effect on the acute hypothalamic release of either GHRH or SRIH. It is concluded that IL-1 stimulates the acute hypothalamic release of GHRH and SRIH, and that this effect is mediated by cyclo-oxygenase products. The marked IL-1 stimulation of hypothalamic SRIH release may override the minor increase of GHRH increase, and may thus contribute to disturbances in growth seen in the presence of chronic inflammation.


Asunto(s)
Hormona Liberadora de Hormona del Crecimiento/metabolismo , Hipotálamo/metabolismo , Interleucina-1/farmacología , Interleucina-6/farmacología , Somatostatina/metabolismo , Factor de Necrosis Tumoral alfa/farmacología , Animales , Relación Dosis-Respuesta a Droga , Hipotálamo/efectos de los fármacos , Hipotálamo Medio/efectos de los fármacos , Hipotálamo Medio/metabolismo , Indometacina/farmacología , Cinética , Masculino , Técnicas de Cultivo de Órganos , Radioinmunoensayo , Ratas , Ratas Endogámicas , Proteínas Recombinantes/farmacología
13.
Clin Pharmacol Ther ; 42(2): 175-80, 1987 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3301151

RESUMEN

We evaluated whether an enteric-coated aspirin formulation showed a "presystemic" component in its antiplatelet effect and if so would spare vascular cyclooxygenase. In six healthy volunteers, 30 to 45 minutes after ingestion of 325 mg enteric-coated aspirin, platelet thromboxane A2 generation was inhibited by about 20% before any drug could be detected in the peripheral venous blood. A further decline in thromboxane A2 generation occurred with appearance of aspirin in blood between 60 and 240 minutes. No presystemic component could be detected after 325 mg aspirin tablets. Ten patients undergoing saphenectomy received 325 mg of either aspirin tablet or enteric-coated aspirin; 12 hours later platelet thromboxane A2 and peripheral vascular prostacyclin generation were significantly reduced by 98% and 58%, respectively. The effects of the two aspirin formulations were not different. Aspirin formulations with "presystemic" component in their antiplatelet effect may not necessarily result in sparing of peripheral vascular cyclooxygenase.


Asunto(s)
Aspirina/metabolismo , Plaquetas/efectos de los fármacos , Epoprostenol/antagonistas & inhibidores , Tromboxano A2/antagonistas & inhibidores , Adulto , Aspirina/administración & dosificación , Aspirina/sangre , Femenino , Humanos , Cinética , Salicilatos/sangre , Ácido Salicílico , Vena Safena/cirugía , Comprimidos Recubiertos , Tromboxano B2/antagonistas & inhibidores , Tromboxano B2/sangre
14.
Neurology ; 53(3): 622-4, 1999 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-10449131

RESUMEN

We investigated MRI activity in MS during the menstrual cycle in relation to physiologic sex hormone fluctuations. Eight women with relapsing-remitting MS were submitted to serial brain gadolinium-enhanced MRI examinations over a 3-month period in two alternate follicular and luteal phases of the menstrual cycle. The ratio of progesterone/17-beta-estradiol during the luteal phase was significantly associated with both number (r = 0.6, p = 0.03) and volume (r = 0.7, p = 0.009) of enhancing lesions, providing support for a role of these hormones as immunomodulatory factors in MS.


Asunto(s)
Estrógenos/fisiología , Ciclo Menstrual/fisiología , Esclerosis Múltiple/patología , Esclerosis Múltiple/fisiopatología , Adulto , Femenino , Humanos , Imagen por Resonancia Magnética
15.
Exp Gerontol ; 24(2): 159-71, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2721604

RESUMEN

Doxorubicin (Dx) toxicity was compared in old (24 months) and young (6 weeks) Crl:CD(SD) BR male rats, and a clear age-related increase was found. The mortality of all animals receiving a single i.v. Dx dose was followed for 270 days. Old rats died after doses of 2.5 mg/kg, while young animals died after doses two times higher, 5 mg/kg. In old rats body weight loss started 10 to 15 days after Dx, compared to 50 to 80 days for young animals. In young and old rats pharmacokinetic and metabolic studies of Dx were conducted in vivo and in the liver perfusion model. Peak levels of Dx and areas under the time/concentration curves (AUC) in serum and in several tissues of old rats were 1.5 to 2 times higher than in young rats. Concentrations of Dx metabolites in serum and tissues (doxorubicinol, Dxol, and doxorubicinone, Dxone) in young and old rats were not noteworthy. However, higher percentages of Dxone than Dxol were found in both groups in vivo and in vitro. Old livers appeared to produce more Dxone as a percentage, particularly in the bile, which was higher. Urinary elimination of Dx markedly slowed with age; only small amounts of the metabolites were eliminated in urine. In vivo and in vitro availability of Dx and its metabolites is discussed in view of their possible role in the greater toxicity observed in 24-month-old rats.


Asunto(s)
Envejecimiento/metabolismo , Doxorrubicina/toxicidad , Animales , Peso Corporal/efectos de los fármacos , Doxorrubicina/farmacocinética , Hígado/efectos de los fármacos , Masculino , Tamaño de los Órganos/efectos de los fármacos , Perfusión , Ratas , Ratas Endogámicas
16.
Biochem Pharmacol ; 35(2): 209-15, 1986 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-3942596

RESUMEN

The antitumoral activity and metabolism of 1-(4-acetylphenyl)-3,3-dimethyltriazene [pAc-(CH3)2] and 1-(4-acetylphenyl)-3,3-diethyltriazene [pAc-(C2H5)2] were studied in mice. pAc-(CH3)2 showed significant antitumoral activity against M5076 ovarian reticular cell sarcoma, L1210 leukemia, EL 4 lymphoma in mice, but not against Lewis lung carcinoma. pAc-(C2H5)2 was inactive in all these murine tumors and was much more toxic than pAc-(CH3)2. pAc-(CH3)2 and pAc-(C2H5)2 were rapidly metabolized in vitro and in vivo to their respective monoalkyltriazenes and to 4-aminoacetophenone (pAc-NH2). In vitro, 79% of the dimethyltriazene was metabolized to its monomethyl analogue, but only 27% of the diethyltriazene was metabolized to the monoethyltriazene. The monoalkytriazenes were almost completely biotransformed to pAc-NH2 by a 9000 g liver fraction. The metabolic pattern in the in vitro study was comparable to that found in vivo.


Asunto(s)
Antineoplásicos , Neoplasias Experimentales/tratamiento farmacológico , Triazinas/metabolismo , Animales , Femenino , Leucemia L1210/tratamiento farmacológico , Linfoma/tratamiento farmacológico , Masculino , Tasa de Depuración Metabólica , Ratones , Metástasis de la Neoplasia , Sarcoma Experimental/tratamiento farmacológico , Relación Estructura-Actividad , Triazinas/uso terapéutico , Triazinas/toxicidad
17.
J Clin Pharmacol ; 37(9): 828-33, 1997 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9549637

RESUMEN

No studies have examined the pharmacokinetics of isosorbide dinitrate (ISDN) after infusion of long duration, even though such infusions are used in patients. We therefore measured ISDN and its active metabolites, isosorbide-5-mononitrate (IS5MN) and isosorbide-2-mononitrate (IS2MN), in plasma of 9 healthy volunteers who received a continuous intravenous infusion of ISDN for 24 hours at a dose rate that lowered diastolic blood pressure by 10% during the first 30 minutes of infusion. All subjects tolerated the infusion except one who experienced intolerable headache. Five subjects received 1 microgram.min-1.kg-1, one 2 micrograms.min-1.kg-1, and two 4 micrograms.min-1.kg-1 ISDN, whereas the full rate of 6 micrograms.min-1.kg-1 was used continuously in one subject. At all infusion rates the plasma concentrations of ISDN were higher at 24 hours than at earlier times, suggesting that a steady-state condition had not been reached at that time. The same was true for the mononitrate metabolites, which reached higher plasma concentrations and were cleared more slowly than the parent compound after the end of the infusion. Apparent elimination half-lives of ISDN, IS2MN, and IS5MN were 67 +/- 10 minutes, 115 +/- 13 minutes, and 272 +/- 38 minutes, respectively. Comparison of low-rate infusions (1 and 2 micrograms.min-1.kg-1) with high-rate infusions (4 and 6 micrograms.min-1.kg-1) showed that the plasma concentration ratios at 24 hours of mononitrate metabolites to parent drug and apparent plasma clearance of ISDN were almost halved at the higher infusion rates.


Asunto(s)
Dinitrato de Isosorbide/farmacocinética , Vasodilatadores/farmacocinética , Adulto , Humanos , Infusiones Intravenosas , Dinitrato de Isosorbide/administración & dosificación , Masculino
18.
Neuropeptides ; 36(6): 391-5, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12507432

RESUMEN

A role of nerve growth factor (NGF) in the neuro-endocrine-immune interactions has been recently suggested by the presence of NGF and its receptors in cells of the immune and endocrine systems. The improvement in the comprehension of the role played by NGF in humans is linked to the availability of a sensitive and reliable method to quantify NGF concentrations in body fluids and tissues. As a consequence of different methods used, normal levels of human serum NGF reported in the literature show wide differences. The present results indicate that ELISA appears very sensitive (detection limit 1.4pg/ml) and allows the discrimination of subtle variations of serum NGF concentrations. ELISA performed in serum obtained from men indicated that NGF concentration was 40.8+/-10.8pg/ml, whereas women showed significantly lower levels that were influenced by the menstrual cycle. In particular, the mean value of this neurotrophin during the follicular phase was 8.2+/-1.4pg/ml; the luteal phase, in turn, showed levels up to 14.4+/-2.9pg/ml. The difference of serum NGF concentrations between the follicular and luteal phase in each woman was statistically significant. Differences in NGF concentrations between men and women (in both phases of the menstrual cycles) were also statistically significant. In conclusion, a possible role of sex steroids as modulators of NGF secretion in humans is strongly supported by the present paper. However, mechanisms underlying this phenomenon are still unknown. The evidence indicating physiological sex hormone-related variations in NGF levels would be of interest in view of the possible use of circulating NGF modifications as a laboratory biomarker in different diseases.


Asunto(s)
Factor de Crecimiento Nervioso/sangre , Caracteres Sexuales , Adulto , Femenino , Fase Folicular/sangre , Humanos , Técnicas para Inmunoenzimas , Fase Luteínica/sangre , Masculino
19.
Cancer Chemother Pharmacol ; 13(3): 211-4, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-6488441

RESUMEN

Plasma levels of VM26 were assayed by HPLC in six ovarian cancer patients with normal renal and liver function who received the drugs as an initial 1-h IV infusion of 80 mg/m2 followed by a 24-h IV infusion of 120 mg/m2. These doses and infusion rates were chosen on the basis of mean VM26 clearance values found in a previous study, with the aim of reaching plasma steady-state levels of approximately 6 micrograms/ml in a short time. Plasma steady-state levels of 4-10 micrograms/ml, close to those predicted theoretically, were in fact attained at 4-9 h during the second, slower infusion. Mean half-lives and clearance values were 8.6 +/- 1.1 h and 0.78 +/- 0.08 l/h/m2. Six percent of the VM26 dose was recovered as unchanged drug in the urines collected up to 24 h after the end of infusion. The glucuronide of VM26 aglycone (4'-demethylepipodophyllotoxin) was identified in the urine of all patients, in amounts corresponding to about 8% of the drug dose.


Asunto(s)
Neoplasias Ováricas/tratamiento farmacológico , Podofilotoxina/análogos & derivados , Tenipósido/administración & dosificación , Animales , Esquema de Medicación , Femenino , Inyecciones Intravenosas , Cinética , Tasa de Depuración Metabólica , Tenipósido/metabolismo , Tenipósido/orina
20.
Cancer Chemother Pharmacol ; 20(3): 239-42, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-2824081

RESUMEN

Three patients with lung cancer (1 SCLC, 2 NSCLC) and pericardial malignant effusion received 100 mg/m2 Teniposide (VM 26) i.v. and, 1 week later, 50 mg/m2 intrapericardially. Plasma, pericardial, and urine levels of the drug were measured in all patients after the two treatments by a HPLC assay. After intrapericardial administration, a high VM 26 concentration was found in the pericardial cavity and slow systemic drug absorption was observed. Since the drug AUC after intrapericardial administration was approximately 15-21 times that after i.v. administration, it could be that this treatment is more effective against neoplastic deposits localized in the pericardium. Even though this small series does not permit conclusions to be drawn on the efficacy of VM 26 given intrapericardially, the lack of local toxicity, minimal systemic toxicity, and the response observed in two out of three patients given intrapericardial VM 26 suggest that further investigation should be carried out on this method of VM 26 administration.


Asunto(s)
Derrame Pericárdico/tratamiento farmacológico , Podofilotoxina/análogos & derivados , Tenipósido/farmacocinética , Anciano , Carcinoma de Pulmón de Células no Pequeñas/complicaciones , Carcinoma de Células Pequeñas/complicaciones , Cromatografía Líquida de Alta Presión , Humanos , Infusiones Intravenosas , Infusiones Parenterales , Neoplasias Pulmonares/complicaciones , Masculino , Persona de Mediana Edad , Derrame Pericárdico/etiología , Derrame Pericárdico/metabolismo , Pericardio , Tenipósido/administración & dosificación , Tenipósido/sangre
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