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1.
Rev Med Liege ; 76(4): 232-238, 2021 Apr.
Artículo en Francés | MEDLINE | ID: mdl-33830685

RESUMEN

As the prevalence of cancers increases with age, some elderly patients are confronted with multiple tumoural pathologies. The clinical case of a 70-year-old patient with adenocarcinoma of the breast and multiple myeloma complicated by severe renal failure illustrates the complexity of oncogeriatric management. The geriatric assessment makes it possible to detect frailty and provides assistance in the development of a personalized care plan while respecting the quality of life.


Comme la prévalence des cancers augmente avec l'âge, certains patients âgés se trouvent confrontés à plusieurs pathologies tumorales. Ce cas clinique d'une patiente de 70 ans, avec un adénocarcinome du sein et un myélome multiple compliqué d'une insuffisance rénale sé-vère, illustre la complexité de la prise en charge oncogériatrique. En effet, l'évaluation gériatrique permet de dépister la fragilité et apporte une aide à l'élaboration d'un plan de soins personnalisé en respectant la qualité de vie.


Asunto(s)
Neoplasias de la Mama , Fragilidad , Mieloma Múltiple , Anciano , Neoplasias de la Mama/complicaciones , Neoplasias de la Mama/terapia , Evaluación Geriátrica , Humanos , Mieloma Múltiple/complicaciones , Mieloma Múltiple/diagnóstico , Mieloma Múltiple/terapia , Calidad de Vida
3.
Phys Rev Lett ; 110(26): 265507, 2013 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-23848899

RESUMEN

A detailed theoretical study of the elementary mechanisms occurring during the shear-coupled grain boundary (GB) migration at low temperature is performed focusing on both the energetic and structural characteristics. The migration of a Σ13(320) GB in a copper bicrystal in response to external shear displacements is simulated using a semiempirical potential. The minimum energy path of the shear-coupled GB migration is computed using the nudge elastic band method. The GB migration occurs through the nucleation and motion of GB steps identified as disconnections. Energy barriers for the GB and disconnection migrations are evaluated.

4.
Allergy ; 67(3): 403-12, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22188019

RESUMEN

BACKGROUND: Nasal polyposis, a chronic inflammatory disease affecting the upper airways, is a valuable and accessible model to investigate the mechanisms underlying chronic inflammation. The main objective of this study was to investigate a potential involvement of the unfolded protein response (UPR) in the context of oxidative stress and inflammation in nasal epithelial cells from nasal polyps (NP). METHODS: Epithelial cells from NP (n = 20) and normal mucosa (Controls, n = 15) in primary culture were analyzed by global proteomic approach and cell biology techniques for the glucose-regulated protein 78 (GRP78), the spliced X-box-binding protein 1 (sXBP-1), the glucose-regulated protein 94 (GRP94), and the calreticulin (immunoblot, mass spectrometry, immunocytochemistry). RESULTS: Proteomics analysis of human nasal epithelial cells in culture revealed the activation of the unfolded protein response in NP. Systematic cell biology and biochemical analysis of two markers (GRP78, sXBP-1) in the presence and absence of oxidative stress in NP showed a susceptibility of the unfolded protein response to oxidative stress compared to controls at least partially linked to an abnormal redox state of the protein disulfide-isomerase 4. This unfolded protein response was correlated with mitochondrial depolarization and secretion of interleukin 8 (IL-8) and leukotriene B4 (LTB4) and was prevented by mitochondrial antioxidant. CONCLUSIONS: We show the existence of UPR in nasal epithelial cells that is linked to oxidative stress leading to IL-8 and LTB4 secretions. These mechanisms may participate in chronic inflammation in nasal polyposis.


Asunto(s)
Células Epiteliales/patología , Inflamación/inmunología , Mucosa Nasal/inmunología , Pólipos Nasales/fisiopatología , Estrés Oxidativo , Respuesta de Proteína Desplegada , Antioxidantes/farmacología , Células Cultivadas , Chaperón BiP del Retículo Endoplásmico , Células Epiteliales/inmunología , Células Epiteliales/metabolismo , Regulación de la Expresión Génica , Humanos , Interleucina-8/metabolismo , Leucotrieno B4/metabolismo , Mucosa Nasal/citología , Pólipos Nasales/inmunología , Proteoma , Proteómica
5.
J Phys Chem A ; 116(41): 10082-9, 2012 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-22650370

RESUMEN

L(2,3)-edge X-ray magnetic circular dichroism (XMCD) spectra have been measured for the well-defined dilute Ni(II) and Mn(II) ions doped into a MgO crystal, with sub-Kelvin dilution refrigerator cooling and 2 T magnetic field magnetization. A 30-element Ge array X-ray detector has been used to measure the XMCD for these dilute ions, whose concentrations are 1400 ppm for Ni(II) and 10,000 ppm for Mn(II). Large XMCD effects have been observed for both Ni(II) and Mn(II), and multiplet simulation described the observed spectra. The fluorescence-detected L-edge absorption spectrum and XMCD of Ni(II) in MgO are comparable with both theoretical calculations and the total electron yield measured ions in similar chemical environments, at least qualitatively validating the use of the sensitive fluorescence detection technique for studying XMCD for dilute 3d metal ions, such as various metalloproteins. Sum rule analyses on the XMCD spectra are also performed. In addition, these XMCD measurements have also been used to obtain the sample's magnetization curve and the beamline's X-ray helicity curve. This study also illustrated that bend magnet beamlines are still useful in examining XMCD on dilute and paramagnetic metal sites.


Asunto(s)
Fluorescencia , Óxido de Magnesio/química , Campos Magnéticos , Manganeso/química , Metaloproteínas/química , Níquel/química , Dicroismo Circular , Rayos X
6.
Biomacromolecules ; 11(11): 2966-75, 2010 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-20931958

RESUMEN

A new reversible gelation pathway is described for alginates in aqueous media. From various samples differing by their mannuronic/guluronic content (M/G), both enthalpic and viscoelastic experiments demonstrate that alginates having a high M content are able to form thermoreversible assemblies in the presence of potassium salts. The aggregation behavior is driven by the low solubility of M-blocks at low temperature and high ionic strength. In semidilute solutions, responsive assemblies induce a strong increase of the viscosity below a critical temperature. A true physical gel is obtained in the entangled regime, although the length scale of specific interactions between M-blocks decreases with increasing density of entanglements. Cold setting takes place at low temperatures, below 0 °C for potassium concentrations lower than 0.2 mol/kg, but the aggregation process can be easily shifted to higher temperatures by increasing the salt concentration. The self-assembling process of alginates in solution of potassium salts is characterized by a sharp gelation exotherm and a broad melting endotherm with a large hysteresis of 20-30 °C between the transition temperatures. The viscoelastic properties of alginate gels in potassium salts closely depend on thermal treatment (rate of cooling, time, and temperature of storage), polymer and salt concentrations, and monomer composition as well. In the case of alginates with a high G content, a similar aggregation behavior is also evidenced at higher salt concentrations, but the extent of the self-assembling process remains too weak to develop a true gelation behavior in solution.


Asunto(s)
Alginatos/química , Frío , Cationes/química , Geles/química , Concentración Osmolar , Polímeros/química , Sales (Química)/química , Soluciones , Viscosidad
9.
Cancer Res ; 61(4): 1693-8, 2001 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-11245485

RESUMEN

The inhibition of the Na+/K+-ATPase by cardiotonic drugs like ouabain deeply perturbs both the properties of the cell membrane and the ionic composition of the cytoplasm and hence alters fundamental cell reactions. These three types of reactions may be involved in the stimulation of multidrug resistance 1 (MDR-1) gene expression and the synthesis of permeability glycoprotein [P-glycoprotein (P-gp)]. We have determined whether ouabain, which binds to an extracellular motif of the Na+/K+-ATPase, stimulates MDR-1 gene expression by measuring both mRNA and protein and whether the resulting P-gp extrudes hydrophobic compounds and causes resistance to antimitotic agents. The experiments were performed on Calu-3 cells, a human cell line from a pulmonary carcinoma. Northern blotting showed that treating the cells with submicromolar concentrations of ouabain stimulated MDR-1 gene expression within 24 h. The ouabain-induced stimulation of MDR-1 expression was not restricted to Calu-3 cells but also occurred in human carcinomatous colon (T-84 and HT-29) and hepatic (H7V3) cells. However, it is not ubiquitous because it was not found in HeLa cells. The stimulation was reproduced by other Na+/K+-ATPase inhibitors and occurred via enhanced gene transcription, apparently due to the increased cytosolic calcium concentration. Ouabain also increased the membrane content of P-gp, as detected by immunoblotting and immunohistology. We have developed a microvideo assay based on the properties of acetoxymethyl ester calcein and calcein to show that this P-gp extruded the hydrophobic acetoxymethyl ester calcein. Ouabain also caused the Calu-3 cells to become resistant to doxorubicin and vinblastine. Thus, although ouabain acts extracellularly, it may stimulate MDR-1 gene expression and P-gp synthesis and make cells resistant to hydrophobic cytotoxic compounds.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/biosíntesis , Resistencia a Múltiples Medicamentos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Genes MDR/efectos de los fármacos , Ouabaína/farmacología , Mucosa Respiratoria/efectos de los fármacos , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Antibióticos Antineoplásicos/farmacocinética , Antibióticos Antineoplásicos/farmacología , Antineoplásicos Fitogénicos/farmacocinética , Antineoplásicos Fitogénicos/farmacología , Transporte Biológico/efectos de los fármacos , Cardiotónicos/farmacología , Línea Celular , Doxorrubicina/farmacocinética , Doxorrubicina/farmacología , Resistencia a Antineoplásicos , Inhibidores Enzimáticos/farmacología , Fluoresceínas/farmacocinética , Colorantes Fluorescentes/farmacocinética , Humanos , ARN Mensajero/genética , Mucosa Respiratoria/metabolismo , Mucosa Respiratoria/fisiología , Estimulación Química , Células Tumorales Cultivadas , Vinblastina/farmacocinética , Vinblastina/farmacología
10.
Cancer Res ; 44(5): 2219-24, 1984 May.
Artículo en Inglés | MEDLINE | ID: mdl-6713410

RESUMEN

The present work compared the blood variations in some committed stem cells (CSC), and corresponding differentiated WBC during the first three courses of a 6-day sequential chemotherapy given to 16 breast cancer patients for 28 days each. The granulomonocytic and lymphocytic colony-forming unit levels in blood were significantly lowered in cancer patients before treatment. These CSC appeared to have cyclic variations following each course of chemotherapy. In granulomonocytic colony-forming units, a nadir was observed by Day 15, followed by a sharp rebound above the initial values by Days 22 to 24, which was not affected in magnitude by the continuation of treatment. In lymphocytic colony-forming units, the Day 1 level increased with the continuation of chemotherapy. The initial decrease was less marked, but by Day 15 a minimal level was also observed, followed by a progressive increase to reach a maximum by Day 28. Leukocytes and granulocytes reached a nadir by Days 16 to 17 and recovered by Day 25. The cyclic evolution of monocytes was less apparent as was that of lymphocytes; however, there was less restoration of monocytes and lymphocytes than of granulocytes at the end of the resting period. This study showed: (a) an apparent relationship between the level of CSC in blood, and subsequent variations in the corresponding mature cells of the same lineage; and (b) a weak interval of time between the nadir and peaks of CSC and the corresponding mature cells, which was more evident in the granulocytic lineage. These observations seemed to be of physiological importance, but the possible prediction value of peripheral granulomonocytic colony-forming unit peak magnitude following treatment remains to be established.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/fisiopatología , Células Madre Hematopoyéticas/fisiología , Adulto , Anciano , Neoplasias de la Mama/tratamiento farmacológico , Diferenciación Celular , Ciclofosfamida/administración & dosificación , Doxorrubicina/administración & dosificación , Femenino , Fluorouracilo/administración & dosificación , Células Madre Hematopoyéticas/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Valores de Referencia , Vincristina/administración & dosificación
11.
J Clin Oncol ; 10(10): 1615-23, 1992 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1383435

RESUMEN

PURPOSE: Of the 737 patients with aggressive lymphoma who were treated with the LNH-84 regimen, 244 with progressive disease after complete remission or partial response were analyzed retrospectively to determine the influence of intensive chemotherapy with bone marrow transplantation (BMT) on survival. PATIENTS AND METHODS: Forty-four patients were treated with salvage chemotherapy, followed by autologous bone marrow transplantation (ABMT) in 40 and allogeneic BMT in four. The other 200 patients were treated with chemotherapy only. RESULTS: Salvage treatment produced an objective response in 57% of the patients; 23% achieved a second complete remission. Median overall survival was longer for patients who were treated with ABMT than for those who were treated with chemotherapy only (12.4 v 6.7 months), as was median freedom from progression (FFP) survival (7.7 v 4 months). In multiparametric analysis, ABMT and normal initial lactic dehydrogenase (LDH) level were the primary parameters associated with longer survival. This is also true when (1) only patients younger than 60 years of age, (2) only patients who responded to salvage regimen, or (3) only patients with both conditions were included in the analysis. Patients who were not transplanted had a 1.69 to 2.26 relative risk of dying from their disease compared with those who were treated with intensive chemotherapy plus ABMT. CONCLUSION: This study produced more evidence of the favorable impact of intensive chemotherapy with bone marrow rescue on survival in lymphoma patients who had relapsed.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Trasplante de Médula Ósea , Linfoma/tratamiento farmacológico , Linfoma/cirugía , Bleomicina/administración & dosificación , Ciclofosfamida/administración & dosificación , Doxorrubicina/administración & dosificación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Prednisolona/administración & dosificación , Pronóstico , Recurrencia , Estudios Retrospectivos , Terapia Recuperativa , Análisis de Supervivencia , Vindesina/administración & dosificación
12.
J Clin Oncol ; 15(4): 1302-8, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9193321

RESUMEN

PURPOSE: A series of 53 patients with poor-prognosis epithelial ovarian cancer treated with high-dose chemotherapy (HDC) followed by hematopoietic rescue was retrospectively studied from the day of diagnosis for toxicity and long-term survival analysis. PATIENTS AND METHODS: Patients were treated with surgery followed by cisplatin combination chemotherapy. After second-look operation (SLO), HDC was administered: 23 patients received melphalan (140 mg/m2 on day 1) and 30 patients received a combination of carboplatin (400 mg/m2 on days 1 to 4) and cyclophosphamide (1.6 g/m2 on days 1 to 4). After HDC, autologous stem-cell transplantation was performed for hematologic support. RESULTS: One patient died of cardiac failure after HDC, but the acute toxicity was acceptable for the other patients. With a median follow-up of 81.5 months, the 5-year overall survival rate for the 53 patients was 59.9% and the disease-free survival (DFS) rate at 5 years was 23.6%. Twenty-four patients (45.3%) were alive, 12 with no evidence of disease and 12 with recurrent disease. The best results were achieved in 19 patients with pathologic complete response at SLO (74.2% 5-year overall survival; 32.8% 5-year DFS). CONCLUSION: HDC followed by autologous stem-cell support is a well-tolerated therapeutic approach for patients with poor-prognosis ovarian carcinoma. In this report, the 59.9% survival of 53 patients at 5 years must be compared to the 20% to 30% 5-year survival observed after conventional therapy. These results should be confirmed by an ongoing prospective randomized trial.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Carcinoma/tratamiento farmacológico , Trasplante de Células Madre Hematopoyéticas , Neoplasias Ováricas/tratamiento farmacológico , Adulto , Antineoplásicos Alquilantes/administración & dosificación , Carboplatino/administración & dosificación , Carcinoma/patología , Ciclofosfamida/administración & dosificación , Femenino , Humanos , Melfalán/administración & dosificación , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias Ováricas/patología , Pronóstico , Estudios Retrospectivos , Terapia Recuperativa , Análisis de Supervivencia , Resultado del Tratamiento
13.
Cell Signal ; 7(2): 131-8, 1995 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7794685

RESUMEN

In the present work, we compared biochemical and electrophysiological actions of isoproterenol on frog proximal tubular cells by using tubule suspensions and giant entities obtained by cell fusion. Isoproterenol (ISO) dose-dependently stimulated cAMP production in tubule suspension and depolarized the "giant cell" membrane. Both effects were triggered by beta receptor occupancy, but strongly differed in their concentration-dependency, since depolarization occurred with an ISO concentration as low as 10(-12) mol/l whereas cAMP accumulation could be seen only with more than 10(-8) mol/l ISO. ISO-induced membrane depolarization was mimicked by forskolin which directly stimulated the catalytic subunit of adenylyl cyclase. In both isoproterenol- and forskolin-stimulated giant cells, membrane depolarization was accompanied by a decrease in membrane conductance, and both effects were inhibited by tetraethylammonium (TEA) and 4-aminopyridine (4-AP). On the other hand, ISO- and forskolin-induced cAMP production were not affected by TEA. The present data thus show that isoproterenol produces two independent effects in frog proximal tubule: it depolarizes the cell membrane by blocking a K+ conductance and activates adenylyl cyclase.


Asunto(s)
Isoproterenol/farmacología , Túbulos Renales Proximales/efectos de los fármacos , 4-Aminopiridina/farmacología , Adenilil Ciclasas/metabolismo , Alprenolol/farmacología , Amilorida/farmacología , Animales , Fusión Celular , Colforsina/farmacología , AMP Cíclico/biosíntesis , Células Gigantes/citología , Células Gigantes/efectos de los fármacos , Células Gigantes/metabolismo , Técnicas In Vitro , Túbulos Renales Proximales/citología , Túbulos Renales Proximales/metabolismo , Cinética , Potenciales de la Membrana/efectos de los fármacos , Potasio/metabolismo , Rana ridibunda , Tetraetilamonio , Compuestos de Tetraetilamonio/farmacología
14.
Hypertension ; 8(8): 694-9, 1986 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3733214

RESUMEN

Thrombin-induced serotonin secretion from platelets from age-matched spontaneously hypertensive rats (SHR) and control Wistar-Kyoto rats (WKY) was compared in the presence of different Ca2+ and Mg2+ concentrations. Platelets from SHR were more reactive than those of WKY, and the difference was more marked in 11-week-old than in younger rats. The responses to three concentrations of extracellular Ca2+ and one extracellular Mg2+ concentration of 10(-3) M were compared. A high external Ca2+ concentration (2 X 10(-3) M) increased secretion in platelets of both strains without suppressing the difference between them. Platelets from SHR were more sensitive than those from WKY to a low external Ca2+ concentration (2 X 10(-6) M). Platelet secretion which is independent of external Ca2+ concentration was higher in platelets from SHR than in those from WKY. External Mg2+ exerted an inhibitory effect on serotonin secretion in both types of platelets, but platelets from SHR were less sensitive to Mg2+ than were those from WKY. This inhibitory effect appeared to be complex. It could be observed in the absence of external Ca2+, and in this case, the difference in reactivity between platelets SHR and WKY depended on the external Mg2+ concentration (up to 2 X 10(-3) M). Furthermore, a Mg2+ -induced antagonism of the stimulatory effect of external Ca2+ concentration appeared at higher concentrations of extracellular Mg2+ and was more potent in platelets from WKY than in those from SHR.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Plaquetas/fisiopatología , Hipertensión/fisiopatología , Animales , Plaquetas/efectos de los fármacos , Calcio/fisiología , Magnesio/farmacología , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas WKY , Serotonina/metabolismo
15.
Int J Radiat Oncol Biol Phys ; 18(6): 1315-8, 1990 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2370182

RESUMEN

Between 1984 and 1986, 85 consecutive patients with Stage III-IV or multi-centric squamous cell carcinoma of the head and neck were given three courses of chemotherapy followed by curative external radiotherapy. Induction chemotherapy consisted of either DDP (100 mg/m2, d 1) + 5 FU (1 g/m2/d, d 1-5, continuous infusion) or DDP (100 mg/m2, d4) + Etoposide (60 mg/m2/d, d 1-5, intravenously). Radiotherapy was delivered 70 Gy over 7 weeks in gross tumor and palpable nodes and 50 Gy over 5 weeks in clinically negative nodal areas. Complete response (CR) rates of both the chemotherapies were 39% for the primary and 20% for the nodes whereas partial response (PR) rates were 22% and 40%, respectively. Six months after completion of radiotherapy, 70% of the primaries and 63% of the nodes achieved complete response. The analysis of responses to chemotherapy on one hand and to subsequent radiotherapy on the other shows that the response to chemotherapy can be regarded as predictive for subsequent radiotherapy (p less than 0.001) except in T1-T2 tumors. In these early stages radiotherapy can be efficacious despite a previous failure of chemotherapy (p less than 0.01).


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Células Escamosas/terapia , Neoplasias de Cabeza y Cuello/terapia , Adulto , Anciano , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/radioterapia , Cisplatino/administración & dosificación , Terapia Combinada , Esquema de Medicación , Etopósido/administración & dosificación , Fluorouracilo/administración & dosificación , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Masculino , Persona de Mediana Edad
16.
Int J Radiat Oncol Biol Phys ; 9(3): 393-5, 1983 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-6841193

RESUMEN

From January, 1976 to January, 1980, 141 patients (135 males and 6 females) with Stage III and IV squamous cell carcinoma of the head and neck received a split course of hyperfractionated radiotherapy (HFR). In the first group, involving 91 patients, the therapeutic schedule was as follows: first and fourth week, 7.2 Gy per day in 8 sessions of .9 Gy from Monday to Friday, the second and third week no irradiation was given. Thus, patients were given 72 Gy total dose, fractionated into 80 sessions. Mucosal necrosis and severe hemorrhage were responsible for the death of 26 patients (28%). Therefore the therapeutic protocol was altered for the 50 patients of the second group: during the first and sixth week 6.6 Gy per day in 6 sessions of 1.1 Gy from Monday to Friday. The total dose was thus reduced to 66 Gy fractionated into 60 sessions, resulting in the decrease of toxicity. Regardless of the therapeutic protocol and site of primary, 114 patients (80%) achieved a complete remission and 8 showed a partial remission (greater than 50%), whereas no change was seen for the 19 remainders. Local recurrence appeared in 60 patients (48%). Acute mucositis and laryngeal edema regularly occurred a week after every course of HFR and were considered severe in 40 patients. In spite of toxicity, the median survival is 14 months and 22 patients are still alive in November 1981: 19 without disease, and 8 of these patients have a survival time of at least 3 years.


Asunto(s)
Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeza y Cuello/radioterapia , Adulto , Anciano , Radioisótopos de Cobalto/uso terapéutico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Teleterapia por Radioisótopo , Dosificación Radioterapéutica , Estudios Retrospectivos
17.
Int J Radiat Oncol Biol Phys ; 14(1): 23-5, 1988 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3335458

RESUMEN

Late effects were analyzed in a series of 39 patients with a 2-year minimal follow-up who were treated by rapid hyperfractionated radiotherapy. The total dose was 66-72 Gy delivered in two series of 33-36 Gy separated by a 2-4 week rest interval. The number of daily fractions ranged from 8 to 6 and the interval between each fraction was 2 hr. Late complications consisted of cervical fibrosis, mucosal necrosis, bone necrosis, trismus, and laryngeal edema. Seventy percent of patients experienced late complications, and in 54% of cases, these reactions were considered severe, causing death in 13% of patients. No relationship was found between field sizes, dosimetric data and type and frequency of late effects. It is therefore suggested that the interval between two daily sessions in any multifractionated protocol may be of critical importance.


Asunto(s)
Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeza y Cuello/radioterapia , Traumatismos por Radiación/etiología , Radioterapia/efectos adversos , Carcinoma de Células Escamosas/patología , Estudios de Seguimiento , Neoplasias de Cabeza y Cuello/patología , Humanos , Estadificación de Neoplasias , Dosificación Radioterapéutica
18.
J Hypertens ; 4(5): 551-5, 1986 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3098837

RESUMEN

Platelet reactivity of normotensive and essential hypertensive subjects was examined in vitro. We determined the release of [3H]-serotonin induced by thrombin from washed platelets in the presence of calcium (10(-3) mol/l) or with EGTA (calcium free medium). The release was significantly higher from platelets of hypertensive subjects when compared with those of normotensive subjects. This difference was only found in the presence of external calcium. The present data suggest an intrinsic functional hyperreactivity of platelets from essential hypertensive patients, which may be linked to an alteration in calcium (Ca2+) handling.


Asunto(s)
Plaquetas/metabolismo , Hipertensión/sangre , Trombina/farmacología , Plaquetas/efectos de los fármacos , Tampones (Química) , Calcio/farmacología , Ácido Egtácico/farmacología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Serotonina/metabolismo , Estimulación Química
19.
J Hypertens ; 8(6): 565-72, 1990 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2165091

RESUMEN

In order to determine whether the morphological modifications observed in arterial media of spontaneously hypertensive rats (SHR) could be induced by an abnormal response of the smooth muscle cells to vasoactive agents, we studied the action of angiotensin (Ang) II on cultured aortic smooth muscle cells from both SHR and Wistar-Kyoto rats (WKY). Under our experimental conditions, Ang II exerts a mitogenic action on SHR cells, whereas its effect is very weak on WKY cells. Phospholipase C activation and c-fos and c-myc proto-oncogene expressions induced by Ang II are considerably enhanced in SHR cells, and these abnormalities may be linked to an increased number of Ang II receptors.


Asunto(s)
Angiotensina II/farmacología , Hipertensión/genética , Músculo Liso Vascular/efectos de los fármacos , Animales , Northern Blotting , Células Cultivadas , Hipertensión/patología , Mitógenos , Mitosis , Oncogenes/efectos de los fármacos , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas WKY , Fosfolipasas de Tipo C/metabolismo
20.
J Hypertens ; 7(3): 195-201, 1989 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2708815

RESUMEN

The expression of two oncogenes (conc) c-myc and c-fos, coding for nuclear proteins which play a regulatory role in growth and differentiation, and of two genes coding for two heat shock proteins (HSP) 68 (molecular weight 68,000) and 70 (molecular weight 70,000), which have a protective function during stress, have been investigated by Northern blot analysis of the total RNA, extracted from adult rat ventricle and aorta. (1) The two onc transcripts are absent from these tissues but their expression can be enhanced by a pretreatment with cycloheximide. (2) The HSP70 is, in part, constitutive, while HSP68 is not; both are thermo-inducible in an isolated coronary perfused rat heart. (3) The four messenger RNA (mRNA) are expressed in both ventricles and aorta, 1 or 2 hours after i.p. injection of 6 mg/kg phenylephrine or 12 IU/kg of vasopressin. (4) They are also induced by a continuous or discontinuous injection of angiotensin II (7.5 micrograms/kg per min) for 1-2 h, but only in the aorta. The lack of ventricular response to angiotensin II in rat ventricles has been attributed to the lack of angiotensin II receptors in this tissue. This indicates that, in addition to mechanical factors, circulating hormones which have in common the use of the phosphoinositol pathway, may activate the expression of genes coding for regulatory proteins. This may play a role in the genesis of both ventricular and aortic hypertrophy.


Asunto(s)
Angiotensina II/farmacología , Regulación de la Expresión Génica , Proteínas de Choque Térmico/genética , Fenilefrina/farmacología , Proto-Oncogenes , ARN Mensajero/análisis , Vasopresinas/farmacología , Animales , Aorta/análisis , Northern Blotting , Masculino , Miocardio/análisis , Ratas , Ratas Endogámicas
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