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1.
Data Brief ; 47: 108902, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36747980

RESUMEN

A thorough characterization of base materials is the prerequisite for further research. In this paper, the characterization data of the reference materials (CEM I 42.5 R, limestone powder, calcined clay and a mixture of these three components) used in the second funding phase of the priority program 2005 of the German Research Foundation (DFG SPP 2005) are presented under the aspects of chemical and mineralogical composition as well as physical and chemical properties. The data were collected based on tests performed by up to eleven research groups involved in this cooperative program.

2.
Nat Commun ; 7: 12902, 2016 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-27698341

RESUMEN

Capturing the dynamic electronic band structure of a correlated material presents a powerful capability for uncovering the complex couplings between the electronic and structural degrees of freedom. When combined with ultrafast laser excitation, new phases of matter can result, since far-from-equilibrium excited states are instantaneously populated. Here, we elucidate a general relation between ultrafast non-equilibrium electron dynamics and the size of the characteristic energy gap in a correlated electron material. We show that carrier multiplication via impact ionization can be one of the most important processes in a gapped material, and that the speed of carrier multiplication critically depends on the size of the energy gap. In the case of the charge-density wave material 1T-TiSe2, our data indicate that carrier multiplication and gap dynamics mutually amplify each other, which explains-on a microscopic level-the extremely fast response of this material to ultrafast optical excitation.

3.
Nat Commun ; 3: 1069, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22990865

RESUMEN

Distinguishing insulators by the dominant type of interaction is a central problem in condensed matter physics. Basic models include the Bloch-Wilson and the Peierls insulator due to electron-lattice interactions, the Mott and the excitonic insulator caused by electron-electron interactions, and the Anderson insulator arising from electron-impurity interactions. In real materials, however, all the interactions are simultaneously present so that classification is often not straightforward. Here, we show that time- and angle-resolved photoemission spectroscopy can directly measure the melting times of electronic order parameters and thus identify-via systematic temporal discrimination of elementary electronic and structural processes-the dominant interaction. Specifically, we resolve the debates about the nature of two peculiar charge-density-wave states in the family of transition-metal dichalcogenides, and show that Rb intercalated 1T-TaS(2) is a Peierls insulator and that the ultrafast response of 1T-TiSe(2) is highly suggestive of an excitonic insulator.

4.
Phys Rev Lett ; 105(18): 187401, 2010 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-21231136

RESUMEN

Femtosecond time-resolved core-level photoemission spectroscopy with a free-electron laser is used to measure the atomic-site specific charge-order dynamics of the charge-density wave in the Mott insulator 1T-TaS2. After strong photoexcitation, a prompt loss of charge order and subsequent fast equilibration dynamics of the electron-lattice system are observed. On the time scale of electron-phonon thermalization, about 1 ps, the system is driven across a phase transition from a long-range charge ordered state to a quasiequilibrium state with domainlike short-range charge and lattice order. The experiment opens the way to study the nonequilibrium dynamics of condensed matter systems with full elemental, chemical, and atomic-site selectivity.

5.
Handchir Mikrochir Plast Chir ; 40(4): 267-71, 2008 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-18716987

RESUMEN

The oculocardiac reflex (OCR) is a well-known phenomenon in ophthalmic surgery, but is rarely described in aesthetic blepharoplasty surgery. It was first mentioned in 1908 by Ascher and Dagnini. Since then, ophthalmologists and anaesthesiologists have regarded the onset of the oculocardiac reflex as a significant intraoperative problem, which is undermined by several case reports that describe dysrhythmias which have haved caused morbidity and death. Per definition the OCR is caused by ocular manipulation and involves intraoperative bradycardia by a change of 20 beats/minute compared to the preoperative heart rate or any dysrhythmia during the manipulation via a trigeminal-vagal-mediated reflex arc. Having operated on a 48-year-old, healthy woman in our clinic, who underwent a cardiac arrest during the blepharoplasty procedure, followed by a successful resuscitation, we investigated the onset of the OCR in our blepharoplasty patients within the last 3 years. The onset of the OCR was noted in 22 of 110 (20 %) blepharoplasty patients, mainly affecting younger, low-weighted patients operated under local anaesthesia. Awareness and treatment of this potentially life-threatening oculocardiac reflex are necessary. In most cases the onset of the reflex may be avoided by a gentle operation technique and by refraining from severe traction to the muscle or fat pad. The best treatment of a profound bradycardia caused by the OCR is to release tension to the muscle or fat pad in order to permit the heart rate to return to normal. Intraoperative monitoring is of utmost importance.


Asunto(s)
Blefaroplastia , Paro Cardíaco/fisiopatología , Complicaciones Intraoperatorias/fisiopatología , Reflejo Oculocardíaco/fisiología , Tejido Adiposo/cirugía , Anestesia Local , Presión Sanguínea/fisiología , Bradicardia/epidemiología , Bradicardia/fisiopatología , Estudios Transversales , Electrocardiografía , Femenino , Paro Cardíaco/epidemiología , Humanos , Complicaciones Intraoperatorias/epidemiología , Persona de Mediana Edad , Monitoreo Intraoperatorio , Órbita/cirugía , Resucitación , Factores de Riesgo , Nervio Trigémino/fisiopatología , Nervio Vago/fisiopatología
6.
Eur J Gynaecol Oncol ; 26(4): 372-5, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16122181

RESUMEN

INTRODUCTION: The Papanicolau (Pap) smear is widely accepted by both the public and health authorities as a useful tool for detection of cervical cancer and its precursors. In Israel only opportunistic screening exists and still the incidence of invasive cervical cancer is among the lowest in the world. OBJECTIVES: To examine the existing evidence for the effectiveness of cervical cancer screening by Pap smears; to apply the findings to Israeli data, and to assess the implications for the current cervical cancer screening policy. METHODS: Search of Medline (1966-June 2003) and the Cochrane Library for relevant systematic reviews, controlled trials and cohort studies. RESULTS: There have been no trials of screening for cervical cancer and its precursors and therefore, no direct evidence that screening improves outcomes. A single retrospective cohort study estimated the age-adjusted RR for invasive cervical cancer in women with at least one Pap smear, whether normal or abnormal, compared to women with no smear at 0.4 (95% CI 0.2-0.9). In Israel some 27,800 (range: 20,800-167,000) women need to be screened in order to prevent one case of cervical cancer. The cost of preventing a single case of invasive cervical is approximately 1.288 million NIS (range: 1.643-13.193 million NIS). CONCLUSIONS: An evidence-based approach to the question of the effectiveness of cervical cancer screening using Pap smears has yielded weak evidence. Based on this weak evidence and rough estimations of the effectiveness and cost of mass screening for cervical cancer in Israel, we conclude that the current policy should be maintained.


Asunto(s)
Tamizaje Masivo/métodos , Prueba de Papanicolaou , Neoplasias del Cuello Uterino/diagnóstico , Frotis Vaginal , Adulto , Anciano , Estudios de Cohortes , Femenino , Humanos , Israel , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
7.
Arch Environ Health ; 54(3): 165-71, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10444037

RESUMEN

During the spring of 1995, schoolchildren aged 7-13 y who lived in a rural area in Israel were studied. These children lived in two communities: in one community, the population was exposed to pollution from a cement factory and quarries; the population of the second community was not exposed to pollution from these sources. The children from participating schools performed forced vital capacity, forced expiratory volume in 1 s, peak expiratory flow, forced expiratory flow at 50%, and forced expiratory flow at 25%. Parents completed an American Thoracic Society-National Heart and Lung Institute health questionnaire, which included information about respiratory symptoms and diseases of the children and information about background variables. A trend of higher prevalence of most respiratory symptoms occurred in 638 children who were growing up in the community that bordered the industrial zone, compared with 338 children from the unexposed community. Cough without cold, sputum without cold, and cough accompanied by sputum were the most prevalent symptoms. Asthma diagnosed by a physician was reported more frequently for children who lived near the polluting sources. No consistent trend of reduced pulmonary function tests was observed among children who lived in the polluted community; however, peak expiratory flow was significantly lower among these children. Odds ratio values, calculated from logistic regressions in which we controlled for respiratory problems among parents, mothers who smoked, crowding index, education of mothers, and residential heating, were 3.6 (p value for model = .244) for cough without cold, 4.0 (p value for model = .333) for asthma, and 2.2 (p value for model = .753) for asthma and/or bronchitis in the polluted area, compared with 1.0 in the low-pollution community. Total suspended particulate matter and levels of airborne particles less than 10 microns, measured in the community bordering the industrial zone, very often violated the relevant 24-h Israeli standards of 200 microg/m3 and 150 microg/m3, respectively.


Asunto(s)
Contaminación del Aire/efectos adversos , Enfermedades Respiratorias/epidemiología , Adolescente , Factores de Edad , Asma/epidemiología , Bronquitis/epidemiología , Distribución de Chi-Cuadrado , Niño , Tos/epidemiología , Educación , Padre , Humanos , Israel/epidemiología , Modelos Logísticos , Madres , Pruebas de Función Respiratoria , Enfermedades Respiratorias/diagnóstico , Factores de Riesgo , Población Rural , Fumar/efectos adversos , Encuestas y Cuestionarios
8.
Eur J Pediatr ; 158(6): 519-22, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10378404

RESUMEN

UNLABELLED: Fitting adequate prediction equations for pulmonary function test (PFT) parameters is crucial in the analysis of lung function tests and their interpretation. Our work aimed at studying the necessity of building population specific prediction equations, rather than using prediction equations built-in in commercial equipment. We used as an example results of studies carried out among Israeli schoolchildren. Second to sixth grade children (7-13 years old), 1064 boys and 1211 girls, were studied in Tel-Aviv. PFT (forced vital capacity, forced expiratory volume in 1st second, peak expiratory flow, forced expiratory flow in 50% volume, forced expiratory flow in 75% volume) performed by these children were adjusted for height, weight and age, for each sex separately, by a multiple regression procedure. Predicted PFT parameters of 300 boys and 301 girls aged 7-13 years, living along the southern shore of Israel, were calculated using the equations built for the same aged Tel-Aviv children as well as the prediction equations built-in in the spirometer used. The ratios between the observed PFT parameters in the southern children and their expected values, using the Israeli population specific equations, were around 1.00. Using the built-in equations resulted in ratios around 0.90. CONCLUSION: The development of population specific prediction equations for PFT parameters is necessary. Such equations should be used both in clinical assessment to minimize misclassification (healthy/sick child) and in epidemiological studies.


Asunto(s)
Pruebas de Función Respiratoria , Estatura , Peso Corporal , Niño , Femenino , Humanos , Israel , Masculino , Modelos Estadísticos , Valor Predictivo de las Pruebas , Valores de Referencia , Análisis de Regresión
9.
Blood ; 93(9): 2798-806, 1999 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-10216073

RESUMEN

Lineage-specific growth factors mobilize peripheral blood progenitor cells (PBPC) and accelerate hematopoietic recovery after high-dose chemotherapy. Recombinant human thrombopoietin (rhTPO) may further increase the progenitor-cell content and regenerating potential of PBPC products. We evaluated the safety and activity of rhTPO as a PBPC mobilizer in combination with granulocyte colony-stimulating factor (G-CSF) in 29 breast cancer patients treated with high-dose chemotherapy followed by PBPC reinfusion. Initially, patients received escalating single doses of rhTPO intravenously (IV) at 0.6, 1.2, or 2.4 micrograms/kg, on day 1. Subsequent patients received rhTPO 0.6 or 0.3 micrograms/kg on days -3, -1, and 1, or 0.6 micrograms/kg on days -1 and 1. G-CSF, 5 micrograms/kg IV or subcutaneously (SC) twice daily, was started on day 3 and continued through aphereses. Twenty comparable, concurrently and identically treated patients (who were eligible and would have been treated on protocol but for the lack of study opening) mobilized with G-CSF alone served as comparisons. CD34(+) cell yields were substantially higher with the first apheresis following rhTPO and G-CSF versus G-CSF alone: 4.1 x 10(6)/kg (range, 1.3 to 17.6) versus 0.8 x 10(6)/ kg (range, 0.3 to 4.2), P =.0003. The targeted minimum yield of 3 x 10(6) CD34(+) cells/kg was procured following a single apheresis procedure in 61% of the rhTPO and G-CSF-mobilized group versus 10% of G-CSF-mobilized patients (P =.001). In rhTPO and G-CSF mobilized patients, granulocyte (day 8 v 9, P =.0001) and platelet recovery (day 9 v 10, P =.07) were accelerated, and fewer erythrocyte (3 v 4, P =.02) and platelet (4 v 5, P =.02) transfusions were needed compared with G-CSF-mobilized patients. Peripheral blood platelet counts, following rhTPO and G-CSF, were increased by greater than 100% and the platelet content of PBPC products by 60% to 110% on the first and second days of aphereses (P <.0001) with the greatest effect seen with repeated dosing of rhTPO at 0.6 microgram/kg. rhTPO is safe and well tolerated as a mobilizing agent before PBPC collection. Mobilization with rhTPO and G-CSF, in comparison to a comparable, nonrandomized G-CSF-mobilized group of patients, decreases the number of apheresis procedures required, may accelerate hematopoietic recovery, and may reduce the number of transfusions required following high-dose chemotherapy for breast cancer.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Plaquetas/fisiología , Neoplasias de la Mama/sangre , Neoplasias de la Mama/terapia , Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Hematopoyesis , Células Madre Hematopoyéticas/fisiología , Trombopoyetina/uso terapéutico , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Eliminación de Componentes Sanguíneos , Plaquetas/efectos de los fármacos , Cisplatino/administración & dosificación , Ciclofosfamida/administración & dosificación , Etopósido/administración & dosificación , Femenino , Filgrastim , Factor Estimulante de Colonias de Granulocitos/efectos adversos , Células Madre Hematopoyéticas/efectos de los fármacos , Humanos , Persona de Mediana Edad , Estadificación de Neoplasias , Recuento de Plaquetas/efectos de los fármacos , Proteínas Recombinantes/efectos adversos , Proteínas Recombinantes/uso terapéutico , Trombopoyetina/efectos adversos
10.
Blood ; 91(9): 3509-17, 1998 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-9558412

RESUMEN

An observational study was conducted at 18 transplant centers in the United States and Canada to characterize the platelet recovery of patients receiving myeloablative therapy and stem cell transplantation and to determine the clinical variables influencing recovery, determine platelet utilization and cost, and incidence of hemorrhagic events. The study included 789 evaluable patients transplanted in 1995. Clinical, laboratory, and outcome data were obtained from the medical records. Variables associated with accelerated recovery in multivariate models included (1) higher CD34 count; (2) higher platelet count at the start of myeloablative therapy; (3) graft from an HLA-identical sibling donor; and (4) prior stem cell transplant. Variables associated with delayed recovery were (1) prior radiation therapy; (2) posttransplant fever; (3) hepatic veno-occlusive disease; and (4) use of posttransplant growth factors. Disease type also influenced recovery. Recipients of peripheral blood stem cells (PBSC) had faster recovery and fewer platelet transfusion days than recipients of bone marrow (BM). The estimated average 60-day platelet transfusion cost per patient was $4,000 for autologous PBSC and $11,000 for allogeneic BM transplants. It was found that 11% of all patients had a significant hemorrhagic event during the first 60 days posttransplant, contributing to death in 2% of patients. In conclusion, clinical variables influencing platelet recovery should be considered in the design and interpretation of clinical strategies to accelerate recovery. Enhancing platelet recovery is not likely to have a significant impact on 60-day mortality but could significantly decrease health care costs and potentially improve patient quality of life.


Asunto(s)
Plaquetas/citología , Trasplante de Médula Ósea/métodos , Trasplante de Células Madre Hematopoyéticas/métodos , Antígenos CD34/análisis , Femenino , Humanos , Masculino , Análisis Multivariante , Recuento de Plaquetas , Transfusión de Plaquetas , Análisis de Supervivencia , Factores de Tiempo
11.
Stem Cells ; 16 Suppl 2: 199-206, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-11012192

RESUMEN

Patients undergoing anticancer therapy are often at risk for developing severe and/or prolonged posttreatment thrombocytopenia. This can be associated with significant bleeding; currently, it is treated with supportive platelet transfusions. Frequent platelet transfusions can cause alloimmunization which requires HLA-matched donors and more frequent blood transfusions, and transmission of both viral and bacterial infections via platelet transfusions remains a concern. Furthermore, thrombocytopenia can mandate a decrease in the dose intensity of cytotoxic therapy by causing either delays or dose reductions in therapy administration. An intervention that reduces the risk or shortens the duration of severe thrombocytopenia would represent an important medical advance. Thrombopoietin (TPO), a naturally occurring, glycosylated polypeptide that was cloned by Genentech in 1994, is capable of inducing differentiation of stem cells into megakaryocytes and accelerating the maturation of megakaryocytes, thereby increasing the platelet count. Recombinant human TPO (rHuTPO) is currently undergoing testing in phase 1 and 2 studies in patients receiving myelosuppressive or myeloablative therapy. For the purposes of illustration, preliminary safety and activity data from one ongoing phase 1 myelosuppression trial (rHuTPO in women with advanced gynecologic malignancies receiving carboplatin) and one ongoing phase 1 myeloablation trial (rHuTPO for peripheral blood progenitor cell mobilization prior to myeloablative chemotherapy for high risk breast cancer) will be presented.


Asunto(s)
Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Radioterapia/efectos adversos , Proteínas Recombinantes/administración & dosificación , Trombocitopenia/tratamiento farmacológico , Trombopoyetina/administración & dosificación , Adolescente , Adulto , Anciano , Plaquetas/citología , Plaquetas/efectos de los fármacos , Plaquetas/metabolismo , Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/metabolismo , Quimioterapia Combinada , Femenino , Factor Estimulante de Colonias de Granulocitos/administración & dosificación , Factor Estimulante de Colonias de Granulocitos/efectos adversos , Humanos , Persona de Mediana Edad , Proteínas Recombinantes/efectos adversos , Trombopoyetina/efectos adversos
12.
Eur Respir J ; 10(10): 2279-84, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9387954

RESUMEN

This survey was part of a health monitoring system operated in the vicinity of a new power plant in Israel. The aim of this analysis was to determine whether a temporal trend of increased prevalence of asthma can be observed among cohorts of same-aged children, between 1980 and 1989. Schoolchildren were followed up between 1980 and 1989. They performed pulmonary function tests (PFTs), and their parents filled out American Thoracic Society-National Heart and Lung Institute (ATS-NHLI) health questionnaires. This report deals with the changes in the prevalence of asthma, related respiratory conditions and PFT in four cross-sectional data sets gathered among eighth-grade schoolchildren (aged 13-14 yrs). A highly significant (p=0.0005) increase in the prevalence of asthma (from 5.6% in 1980 to 11.2% in 1989), and of wheezing accompanied by shortness of breath (p=0.0009) could be observed. A similar trend could not be found for the prevalence of bronchitis among these children. PFTs of children suffering from asthma or from wheeze accompanied by shortness of breath were lower than those of healthy children. Changes in prevalence of background variables over time could not explain these findings. The significant rise in the prevalence of asthma coupled with reduced pulmonary function test results among asthmatic children, seems to reflect a true increase in morbidity. Temporal changes in the prevalence of background variables as well as proximity to the power plant could not explain this trend.


Asunto(s)
Asma/epidemiología , Adolescente , Distribución por Edad , Asma/diagnóstico , Asma/etiología , Niño , Estudios de Cohortes , Femenino , Encuestas Epidemiológicas , Humanos , Israel/epidemiología , Masculino , Oportunidad Relativa , Prevalencia , Valores de Referencia , Pruebas de Función Respiratoria , Factores de Riesgo , Distribución por Sexo
13.
J Epidemiol Community Health ; 51(3): 227-32, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9229049

RESUMEN

BACKGROUND: The permit to build and operate the first 1400 megawatt coal fired power plant in Israel was given provided that three monitoring systems-environmental, agricultural, and health monitoring-be set up near the plant. This study was carried out in the framework of a health monitoring system which included a mortality survey, requests for health services, a schoolchildren's health survey, and an adult panel study. METHODS: 2nd, 5th, and 8th grade school-children living in three communities with different expected levels of air pollution were followed up every three years. They performed pulmonary function tests (PFT), and their parents filled out American Thoracic Society-National Heart and Lung Institute (ATS-NHLI) health questionnaires. A follow up of the prevalence of respiratory conditions among the studied schoolchildren in four rounds of tests was carried out. This report deals with the changes in the prevalence of asthma, related respiratory conditions, and PFT in the data sets gathered among 5th grade schoolchildren. RESULTS: A significant (p = 0.0024) increase in the prevalence of asthma could be observed among 5th grade children in all three communities studied between 1980 and 1989. At the same time a significant (p = 0.0172) rise in the prevalence of wheezing accompanied by shortness of breath could be observed. A similar trend could not be found for the prevalence of bronchitis and other respiratory conditions among the studied children. PFT (FEV1, FEV1/FVC) of children suffering from asthma or from wheeze accompanied by shortness of breath were lower than those of healthy children. Changes in the prevalence of background variables over time could not explain the significant rise in the prevalence of asthma among the children. CONCLUSIONS: The significant rise in asthma and related respiratory conditions coupled with reduced PFT observed in this study suggest that the increase over time in the prevalence of asthma is a true increase in morbidity and not due to reporting bias. The increased prevalence of asthma could be observed in all the communities studied and does not seem to be connected with the operation of the power plant.


Asunto(s)
Asma/epidemiología , Contaminación del Aire/análisis , Asma/fisiopatología , Bronquitis/epidemiología , Niño , Estudios de Cohortes , Tos/epidemiología , Femenino , Estudios de Seguimiento , Volumen Espiratorio Forzado/fisiología , Humanos , Israel/epidemiología , Modelos Logísticos , Masculino , Oportunidad Relativa , Centrales Eléctricas , Prevalencia , Ruidos Respiratorios/fisiopatología , Factores de Riesgo , Capacidad Vital/fisiología
14.
J Cardiothorac Vasc Anesth ; 11(4): 463-6, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9187996

RESUMEN

OBJECTIVE: Thyroid hormone (3,5,3'-triiodo-L-thyronine is under investigation as a positive inotrope and vasodilator for patients undergoing cardiac surgery. This study determined the direct effects of triiodothyronine on human blood vessels. DESIGN: Prospective, controlled, in vitro study. SETTING: Laboratory facility in a university teaching hospital. PARTICIPANTS: Small excess segments of internal mammary arteries or saphenous veins were obtained from patients undergoing coronary artery bypass surgery. INTERVENTIONS: Vessel segments were cut into rings to measure isometric tension development in isolated tissue baths containing Krebs-Ringer bicarbonate solution at 37 degrees C. Rings were prestretched in vitro to resting tensions analogous to mean arterial or central venous pressures in vivo and then constricted with potassium or phenylephrine. Rings were exposed to increasing concentrations of triiodothyronine (4 x 10(-12) to 1 x 10(-4) mol/L) to obtain dose-response curves. MEASUREMENTS AND MAIN RESULTS: High concentrations (> or = 3.3 x 10(-5) mol/L) of trilodothyronine produced dose-dependent relaxation of preconstricted rings. The relaxation was not selective for arteries or veins at arterial resting tensions, and with either potassium or phenylephrine as a vasoconstrictor. Propranolol had little effect on subsequent triiodothyronine-induced relaxation of potassium-constricted rings at resting arterial tensions. CONCLUSIONS: Triiodothyronine, in supraphysiological and suprapharmacological concentrations, dilates preconstricted rings of human blood vessels in vitro; however, triiodothyronine had no demonstrable vasomotor effects on human internal mammary artery or saphenous vein in clinically relevant concentrations (10(-9) to 10(-8) mol/L). Triiodothyronine administration in vivo most likely has little direct effect on the tone of human vascular smooth muscle, particularly coronary artery bypass conduits.


Asunto(s)
Cardiotónicos/farmacología , Arterias Mamarias/efectos de los fármacos , Vena Safena/efectos de los fármacos , Triyodotironina/farmacología , Vasodilatadores/farmacología , Presión Sanguínea/efectos de los fármacos , Cardiotónicos/administración & dosificación , Presión Venosa Central/efectos de los fármacos , Puente de Arteria Coronaria , Relación Dosis-Respuesta a Droga , Humanos , Contracción Isométrica/efectos de los fármacos , Soluciones Isotónicas , Músculo Liso Vascular/efectos de los fármacos , Fenilefrina/farmacología , Potasio/farmacología , Propranolol/farmacología , Estudios Prospectivos , Triyodotironina/administración & dosificación , Vasoconstricción/efectos de los fármacos , Vasoconstrictores/farmacología , Vasodilatación , Vasodilatadores/administración & dosificación , Sistema Vasomotor/efectos de los fármacos
15.
Ann Intern Med ; 126(9): 673-81, 1997 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-9139552

RESUMEN

BACKGROUND: Thrombocytopenia is frequently encountered in patients with cancer. It is associated with an increased risk for clinically important bleeding episodes, which increases the demand for platelet transfusion. OBJECTIVE: To assess hematopoietic response to and clinical tolerance of recombinant human thrombopoietin, a recently cloned novel cytokine. DESIGN: Phase I and II clinical cohort study. SETTING: The University of Texas M.D. Anderson Cancer Center, Houston, Texas. PATIENTS: 12 patients with sarcoma who had high risk for severe chemotherapy-induced thrombocytopenia. INTERVENTION: A single intravenous dose of thrombopoietin (0.3 to 2.4 micrograms/kg of body weight) 3 weeks before chemotherapy. MEASUREMENTS: Peripheral blood and bone marrow evaluation before and after thrombopoietin administration. RESULTS: A single dose of thrombopoietin was associated with an increase in platelet counts (mean increase from baseline, 61% to 213%; P = 0.002) in a dose-related manner. This increase began by day 4 in most patients and peaked on a median of day 12. This sustained response was associated with a prolonged serum thrombopoietin half life (20 to 30 hours). The platelets appeared morphologically normal and showed normal aggregation in response to various agonists. Platelet response was accompanied by a dose-related increase in bone marrow megakaryocytes (as much as 4-fold); the expansion of the bone marrow progenitors of myeloid, erythroid, multipotential, and megakaryocytic lineages; and the marked mobilization of progenitors (maximum, 5.7-fold to 10-fold) of multiple cell lineages in the peripheral blood. Treatment was well tolerated, and no serious adverse events occurred. CONCLUSIONS: Thrombopoietin, administered as a single dose, is a potent stimulus for prolonged platelet production in humans. It merits further evaluation for the prevention and treatment of thrombocytopenia.


Asunto(s)
Plaquetas/metabolismo , Megacariocitos/metabolismo , Neoplasias/sangre , Trombocitopenia/prevención & control , Trombopoyetina/administración & dosificación , Anticuerpos/sangre , Antineoplásicos/efectos adversos , Plaquetas/efectos de los fármacos , Médula Ósea/efectos de los fármacos , Hematopoyesis/efectos de los fármacos , Humanos , Inyecciones Intravenosas , Megacariocitos/efectos de los fármacos , Neoplasias/tratamiento farmacológico , Recuento de Plaquetas/efectos de los fármacos , Ploidias , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/farmacocinética , Trombocitopenia/inducido químicamente , Trombopoyetina/farmacocinética
16.
Eur J Cancer ; 33(13): 2198-202, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9470806

RESUMEN

The aim of this phase II study was to characterise the efficacy and toxicity of semisynthetic paclitaxel in patients with metastatic breast cancer. Eligible patients had measurable disease and had been treated with one prior chemotherapy regimen either as adjuvant or for metastatic disease. Semisynthetic paclitaxel was given at a dose of 175 mg/m2 over 3 h every 21 days with dexamethasone, cimetidine and diphenhydramine premedications. 31 patients were entered. All were evaluable for toxicity. 30 patients were evaluable for response because 1 patient was lost to follow-up after receiving one cycle. One patient achieved a complete response and 10 patients achieved partial responses for an overall response rate (CR + PR) of 37% (95% confidence interval 20-56%). 17 patients (55%) experienced at least one episode of grade 3 or 4 neutropenia. There were two episodes of febrile neutropenia complicating 155 cycles of therapy. One of these resulted in a treatment-related death in a patient with pulmonary metastasis. 3 patients required dose reductions for grade 3 sensory neuropathy. Our study shows that the antitumour activity and toxic effects of semisynthetic paclitaxel appear to be identical to the naturally occurring product.


Asunto(s)
Antineoplásicos Fitogénicos/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Paclitaxel/uso terapéutico , Adulto , Anciano , Antineoplásicos Fitogénicos/efectos adversos , Antineoplásicos Fitogénicos/síntesis química , Neoplasias de la Mama/patología , Femenino , Enfermedades Hematológicas/inducido químicamente , Humanos , Persona de Mediana Edad , Metástasis de la Neoplasia , Paclitaxel/efectos adversos , Paclitaxel/síntesis química , Resultado del Tratamiento
17.
Environ Health Perspect ; 103(12): 1110-5, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8747016

RESUMEN

The permit to operate the first coal fired power plant in Israel was issued with the condition that a comprehensive network to monitor its effects on the environment, health, and agriculture must be installed and operated around the plant. The health monitoring system consists of four studies, which started 1 year prior to the operation of the plant and were carried out for 10 years. In the framework of the health monitoring system, a study of requests for health services was carried out. In this survey, 8 clinics of the Sick Fund, served by 16 physicians, were followed up. The clinics were located as near as possible to air pollution monitoring stations and represent expected different levels of pollution. A health recorder summarized each day's visits to each physician and tabulated the total visits for each day and the visits due to respiratory tract complaints. Multivariate stepwise regressions on total as well as on respiratory complaints were carried out. The independent variables in the regressions were sulfur dioxide, meteorological parameters (such as temperature and humidity), and flu epidemics. Temperature was almost always significantly correlated with respiratory complaints, but less correlated with total visits among, adults and children. Sulfur dioxide, most meterological parameters and flu epidemics were not meaningful explanatory factor in the regressions. Ambient air pollution levels did not exceed the Israeli air quality or the more stringent local air quality standards, the monthly and annual average sulfur dioxide and nitrogen oxides values were very low.


Asunto(s)
Contaminación del Aire/efectos adversos , Instituciones de Atención Ambulatoria/estadística & datos numéricos , Carbón Mineral , Enfermedades Pulmonares/epidemiología , Centrales Eléctricas , Adulto , Contaminación del Aire/análisis , Niño , Monitoreo del Ambiente , Monitoreo Epidemiológico , Indicadores de Salud , Encuestas Epidemiológicas , Humanos , Incidencia , Israel/epidemiología , Enfermedades Pulmonares/etiología , Óxidos de Nitrógeno/análisis , Dióxido de Azufre/análisis
18.
J Clin Oncol ; 13(8): 2056-65, 1995 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7543562

RESUMEN

PURPOSE: To provide paclitaxel, an investigational drug at the inception of this study, to women with chemotherapy-refractory metastatic breast cancer and to evaluate response and toxicity in these patients. PATIENTS AND METHODS: Two hundred sixty-seven patients with progressive disease (PD) following at least two chemotherapy regimens for metastatic breast cancer and a contraindication to further doxorubicin treatment received paclitaxel either at 175 mg/m2 intravenously (IV) over 24 hours or at 135 mg/m2 if they had prior irradiation to 30% of marrow-bearing bone or a cumulative dose of mitomycin > or = 20 mg/m2. RESULTS: In a subgroup of patients (n = 172) with measurable disease, four complete responses (CRs) and 36 partial responses (PRs) occurred, for an overall response rate of 23% (95% confidence interval [CI], 17% to 30%). No differences in response rates were noted according either to the number of prior chemotherapy regimens received or to whether patients were considered refractory to doxorubicin. The dose and schedule used in this trial resulted in febrile neutropenia in 45% of patients and a hospitalization rate of 49%. CONCLUSION: Paclitaxel's activity in this multiinstitutional trial in heavily pretreated patients confirms the encouraging results attained in single-institution trials. Although at this dose and schedule paclitaxel may be considered too myelosuppressive for palliative care, supportive measures such as colony-stimulating factors and antibiotics were not used prophylactically. Current research efforts are focusing on whether paclitaxel's activity against breast cancer is dose- and/or schedule-dependent, and on what role it has in patients with less advanced disease.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Paclitaxel/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/patología , Distribución de Chi-Cuadrado , Supervivencia sin Enfermedad , Femenino , Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Humanos , Persona de Mediana Edad , National Institutes of Health (U.S.) , Metástasis de la Neoplasia , Neutropenia/inducido químicamente , Neutropenia/prevención & control , Paclitaxel/administración & dosificación , Paclitaxel/efectos adversos , Derivación y Consulta , Inducción de Remisión , Estados Unidos
19.
J Trop Med Hyg ; 98(2): 95-100, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7714943

RESUMEN

During the period November 1989 to March 1991 a total of 330 patients (269 males and 61 females) with signs and symptoms of uncomplicated lower genital tract infections with Neisseria gonorrhoeae were treated at a sexually transmitted disease clinic in Kampala, Uganda. Patients were randomized for treatment with either intramuscular ampicillin/sulbactam (1 g ampicillin/0.5 g sulbactam), plus 1 g probenecid orally, or ceftriaxone (250 mg). In those cases where N. gonorrhoeae was isolated and the patients returned for a follow-up visit, 70/74 (95%) of the patients treated with ampicillin/sulbactam and 71/72 (99%) of those treated with ceftriaxone had favourable clinical outcomes. All 24 patients with penicillinase-producing N. gonorrhoeae (PPNG) treated with ampicillin/sulbactam had a favourable clinical outcome compared with 95% (20/21) of those with PPNG treated with ceftriaxone. The infecting pathogen was eradicated in 65/71 (92%) of the evaluable patients treated with ampicillin/sulbactam and in 60/63 (95%) of the ceftriaxone group. Both drug regimens were well tolerated and there were no reports of adverse drug effects. In summary, in a predominantly male group of clinic patients in Kampala, Uganda, ampicillin/sulbactam was as safe and effective as ceftriaxone in treating uncomplicated gonococcal infections of the lower genital tract caused by either PPNG or non-PPNG strains.


Asunto(s)
Ceftriaxona/uso terapéutico , Quimioterapia Combinada/uso terapéutico , Gonorrea/tratamiento farmacológico , Penicilinasa/biosíntesis , Probenecid/uso terapéutico , Adulto , Atención Ambulatoria , Ampicilina/uso terapéutico , Femenino , Gonorrea/microbiología , Humanos , Masculino , Neisseria gonorrhoeae/enzimología , Prevalencia , Estudios Prospectivos , Sulbactam/uso terapéutico , Resultado del Tratamiento , Uganda
20.
Arch Environ Health ; 50(2): 112-8, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-7786047

RESUMEN

The purpose of this study was to examine possible links between respiratory conditions among schoolchildren and exposure to environmental tobacco smoke and other home and community exposures. More than 8,000 second- and fifth-grade schoolchildren who lived in three towns along the Israeli coast were administered pulmonary function tests, and their parents completed standardized health questionnaires. The prevalence of the most reported respiratory conditions was found to be higher, some of them significantly so, among children whose fathers or mothers were smokers, compared with children of non-smoking parents. Most respiratory conditions were reported significantly more often for children who were growing up in medium- and highly polluted communities than for children from low-polluted areas. House heating with kerosene or gas was seldom associated with higher prevalence of respiratory conditions among children. No consistent r trend of reduced pulmonary function tests was associated with exposure to environmental tobacco smoke, with community pollution, or with house heating pollution. In conclusion, exposure of schoolchildren to their parents' cigarette smoke and to community air pollution is associated with higher prevalence of respiratory conditions, whereas house heating does not appear to be a public health problem in Israel.


Asunto(s)
Contaminantes Atmosféricos/efectos adversos , Calefacción/efectos adversos , Enfermedades Respiratorias/etiología , Contaminación por Humo de Tabaco/efectos adversos , Estudios de Casos y Controles , Niño , Femenino , Humanos , Israel/epidemiología , Masculino , Prevalencia , Pruebas de Función Respiratoria , Enfermedades Respiratorias/diagnóstico , Enfermedades Respiratorias/epidemiología , Riesgo , Encuestas y Cuestionarios
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