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1.
Presse Med ; 34(16 Pt 1): 1129-36, 2005 Sep 24.
Artículo en Francés | MEDLINE | ID: mdl-16208258

RESUMEN

INTRODUCTION: The patient overload in pediatric healthcare facilities is caused in part by parents bringing their children in for consultations for fever. We conducted a survey in the Lyon metropolitan area to improve our understanding of parents' attitudes towards their children's fever. OBJECTIVE: To assess the frequency and characteristics of healthcare utilization and evaluate parents' knowledge and attitudes before consulting. METHODS: A random sample of families with at least one child under 6 years of age and living in the Lyon metropolitan area was surveyed by telephone, according to a closed questionnaire that was answered by the person usually responsible for the child's health. RESULTS: 202 families were questioned: 58.9% defined fever as a temperature over 38 degrees C, and 82% used rectal thermometers to measure temperature. Among 144 parents of children with an episode of fever within the previous 12 months, 73% called a physician during the episode, 44% of them immediately. Working-class parents called more frequently (90%) than parents who were professionals or managers (74%). Most parents (94%) administered medication to the child several times before calling the physician. Paracetamol and ibuprofen were mentioned most often. 93% of fever episodes led to consultations. DISCUSSION: Our results show that 59% of the sample defined fever as a temperature equal to 38 degrees C and that fever episodes lead commonly and quickly to physician visits, but that parents do use physical methods and drugs to reduce fever before calling a physician.


Asunto(s)
Fiebre/diagnóstico , Fiebre/terapia , Conocimientos, Actitudes y Práctica en Salud , Padres , Adulto , Niño , Estudios Transversales , Femenino , Francia , Humanos , Entrevistas como Asunto , Masculino , Encuestas y Cuestionarios
2.
Opt Express ; 12(23): 5770-6, 2004 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-19488214

RESUMEN

We show strong changes in chemical etching of phosphorus-doped fiber cores due to hydrogen loading and subsequent UV-irradiation using an atomic force microscope. The etch rate of the fiber core in a low concentration hydrofluoric acid solution (HF) is decreasing after hydrogen loading by as much as 30%. In contrast, UV-irradiation of the hydrogenated fiber increases the core etch rate to values of 27% above the etch rate of the pristine fiber. The UV-induced change in etch rate does not depend on pulse fluence, but only on total dose. We attribute the changes in etch rate to a hydrogen- and radiation-induced modification of color center population.

4.
Med Law ; 19(1): 73-85, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10876303

RESUMEN

In Germany, psychiatric patients considered to be a danger to themselves or others may be detained involuntarily for 24 hours, after which the court must be consulted. Only Baden-Württemberg, of all the German states, allows for 72 hours confinement. In a study of 70 patients who were involuntarily hospitalized at a university hospital, it was found that when patients are subject to a 72 hour doctors' court hold, as compared to the 24 hour hold, the number of patients committed to treatment by the court was reduced by about 50%. This applies particularly to younger patients with addiction or neurotic disorders. Schizophrenic patients and older patients with organic brain disease were more likely to be detained on court order. Two-thirds of the patients who were involuntarily hospitalized said that they felt adequately informed about their legal rights, but only about a third felt that involuntary hospitalisation was justified.


Asunto(s)
Internamiento Obligatorio del Enfermo Mental/legislación & jurisprudencia , Conducta Peligrosa , Tiempo de Internación/legislación & jurisprudencia , Alemania , Humanos , Consentimiento Informado/legislación & jurisprudencia , Proyectos Piloto , Estudios Prospectivos , Resultado del Tratamiento
6.
J Infect Dis ; 178 Suppl 1: S58-63, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9852976

RESUMEN

To assess the cost of varicella in young children in France, a prospective study was done in day care centers. Children (1263), who were 3 months to 3 years old and attending day care, were followed over a varicella season. For every child who developed varicella (n = 200), detailed information was obtained by use of parental questionnaires. Questions concerned medical care, days missed from work for parents, and the need for extra baby-sitting. On average, each sick child had one consultation with a physician and received three medications. In half of the families (52%), at least 1 parent had to miss work an average of 4.5 days to care for a sick child. Total costs to society were estimated to be US$352 per family, with medical costs accounting for 22% of the cost. The average eventual cost to parents was $89 per family, including $80 of non-medical costs. This study emphasizes the important socioeconomic impact of varicella in the day care setting in France.


Asunto(s)
Varicela/economía , Varicela/epidemiología , Guarderías Infantiles , Preescolar , Estudios de Cohortes , Costos y Análisis de Costo , Femenino , Francia/epidemiología , Costos de la Atención en Salud , Humanos , Lactante , Masculino , Padres , Estudios Prospectivos , Factores Socioeconómicos , Trabajo
7.
Cell Biol Int ; 22(1): 7-12, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9828077

RESUMEN

Confocal laser scanning microscopy represents a suitable technique to study the localization of cellular components in three dimension. The authors used this technique to analyse cellular events related to mechanical stimulation of integrin receptors on the cell surface. By performing optical sections the distribution of integrin receptors on the apical surface of an osteoblastic cell was determined. Concerning intracellular compartimentalization of signal transduction events, it was demonstrated that mechanical stimulation of integrins induced their linkage to the cytoskeleton. Cytoskeletally associated proteins like vinculin and talin accumulated in the vicinity of the site where the mechanical stress was applied to integrins on the cell surface. Optical sections revealed that clustering of these proteins proceeded to the base of the cell with gradually decreasing extent. In summary, it was demonstrated that the local distribution of cellular components is an important factor in mechanically induced signal transduction.


Asunto(s)
Osteoblastos/metabolismo , Receptores de Superficie Celular/metabolismo , Humanos , Técnicas In Vitro , Integrinas/metabolismo , Microscopía Confocal , Osteoblastos/inmunología , Transducción de Señal , Estrés Mecánico , Talina/metabolismo , Vinculina/metabolismo
8.
J Biol Chem ; 273(9): 5081-5, 1998 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-9478959

RESUMEN

Physical forces play a fundamental role in the regulation of cell function in many tissues, but little is known about how cells are able to sense mechanical loads and realize signal transduction. Adhesion receptors like integrins are candidates for mechanotransducers. We used a magnetic drag force device to apply forces on integrin receptors in an osteoblastic cell line and studied the effect on tyrosine phosphorylation as a biochemical event in signal transduction. Mechanical stressing of both the beta1 and the alpha2 integrin subunit induced an enhanced tyrosine phosphorylation of proteins compared with integrin clustering. Application of cyclic forces with a frequency of 1 Hz was more effective than a continuous stress. Using Triton X-100 for cell extraction, we found that tyrosine-phosphorylated proteins became physically anchored to the cytoskeleton due to mechanical integrin loading. This cytoskeletal linkage was dependent on intracellular calcium. To see if mechanical integrin stressing induced further downstream signaling, we analyzed the activation of mitogen-activated protein (MAP) kinases and found an increased phosphorylation of MAP kinases due to mechanical stress. We conclude that integrins sense physical forces that control gene expression by activation of the MAP kinase pathway. The cytoskeleton may play a key role in the physical anchorage of activated signaling molecules, which enables the switch of physical forces to biochemical signaling events.


Asunto(s)
Antígenos CD/fisiología , Proteínas del Citoesqueleto/metabolismo , Integrinas/fisiología , Receptores de Superficie Celular/fisiología , Calcio/metabolismo , Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , Quelantes/farmacología , Citocalasina D/farmacología , Ácido Egtácico/análogos & derivados , Ácido Egtácico/farmacología , Integrina alfa2 , Integrina beta1/fisiología , Fosforilación , Estimulación Física , Unión Proteica/efectos de los fármacos , Receptores de Transferrina/metabolismo , Transducción de Señal , Tirosina/metabolismo , Vibración
9.
Mol Hum Reprod ; 3(4): 275-83, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9237254

RESUMEN

Adhesiveness of the apical (free) plasma membrane of uterine epithelial cells for trophoblast is essential for the process of human embryo implantation. As epithelial cells are normally repellent, i.e. apically non-adhesive, we argue that a remodelling of the epithelial organization from a polarized to a non-polarized phenotype might prepare the apical pole for cell-cell adhesion during the so-called receptive phase. To identify details of apical adhesiveness we examined human epithelial RL95-2 cells (RL cells) which, in contrast to other cell lines, allow trophoblast to adhere to their apical plasma membrane. To determine whether the cytoskeletal structure is functionally critical for adhesiveness for trophoblast, RL cells were treated with actin depolymerizing cytochalasin D, i.e. 0.4 microM for 120 min. Changes in adhesiveness for trophoblast were monitored with a centrifugal force-based adhesion assay. Moreover, ultrastructural features, organization of the actin network and expression of integrins, i.e. alpha 6, beta 1, beta 4, were studied using electron microscopy, confocal laser scanning microscopy and cell surface immunogold-labelling techniques. Changes in transmission of mechanical signals via integrins into uterine cells were examined using a magnetic drag force device, thereby monitoring intracellular calcium responses. The results suggest that adhesiveness of the free surface of RL cells for human trophoblast requires an intact but non-polarized actin cytoskeleton, apically localized integrins linked to actin, and calcium signalling originating at the free surface.


Asunto(s)
Actinas/metabolismo , Endometrio/citología , Endometrio/metabolismo , Trofoblastos/citología , Trofoblastos/metabolismo , Actinas/efectos de los fármacos , Adhesión Celular , Línea Celular , Membrana Celular/metabolismo , Polaridad Celular , Citocalasina D/farmacología , Citoesqueleto/efectos de los fármacos , Citoesqueleto/metabolismo , Implantación del Embrión/fisiología , Femenino , Humanos , Integrinas/metabolismo , Microscopía Electrónica , Transducción de Señal
10.
Arch Pediatr ; 4(10): 959-66, 1997 Oct.
Artículo en Francés | MEDLINE | ID: mdl-9436493

RESUMEN

BACKGROUND: Crying is called "Infantile colic" when such cries are numerous, paroxystic, difficult to comfort, and without an obvious cause. METHODOLOGY: An information mailing on the study (named Encolie) and the associated methodology was distributed in April 1995 to 212 private practice pediatricians. They have included in the study all infants aged 15 to 119 days who were seen during consultation from June 12 to June 27. They filled out a two page, 32 item, epidemiological questionnaire. Question 31 asked; "following this consultation, would you call for an 'infantile colic' diagnosis for this child? Yes, no. if no, what is your diagnosis?" RESULTS: One hundred and sixty-nine private practice pediatricians out of 212 (79.7%) participated in the study, and have included 2,797 infants 2,773 infant files were analyzed. The 625 infants identified as "colic" (22.5% of all cases), differed from the 2,148 identified as "non-colic" by the following factors: average age (51.3 vs 61.3 days), birth weight (2,226 vs 3,307 g), being a first born (52.7 vs 45.1% of cases), and mother's anxiety (47.8 vs 29.1% of cases). Significant differences were observed concerning feeding behavior (slow or gluttonous feeding), digestive symptoms, and unexplained crying, always more frequent in the case of the infants identified as "colic". These infants received more drugs, and their parents were given more advice on diet and hygiene. The symptoms supporting the "infantile colic" diagnosis were derived using a statistical regression model. They included: frequent and/or unexplained crying at the time of the study, frequent and/or unexplained crying in the past, abdominal distention at the time of the clinical examination, and frequent gas emissions as indicated by parental questioning. Factors associated with this diagnosis were: young age of the child, drugs administered before the consultation, maternal anxiety, anomalies in feeding behavior, and to a lesser degree, low birth weight and mother or father atopy. CONCLUSION: Given the sample size and origin, and the rigor of both the study and the analysis, we believe that these data could be extrapolated to the usual pediatrician's patient population. This highlighting of differences between our two groups indicate the validity of this diagnosis.


Asunto(s)
Cólico/diagnóstico , Cólico/epidemiología , Cólico/terapia , Conducta Alimentaria , Francia , Encuestas Epidemiológicas , Humanos , Lactante , Recién Nacido , Análisis Multivariante , Estudios Prospectivos
11.
Arch Pediatr ; 3(9): 854-60, 1996 Sep.
Artículo en Francés | MEDLINE | ID: mdl-8949344

RESUMEN

BACKGROUND: The efficacy of single daily dose of amikacin has been recently demonstrated in neutropenic children with fever. POPULATION AND METHODS: Eighteen children aged 1 to 15 years were included in the study. All patients were febrile and granulocytopenic and had indwelling intravenous catheter. Amikacin was administered as a 30-minute intravenous infusion once daily (20 mg/kg on day 1, then 15 mg/kg) for 3 to 30 days; the patients received amikacin in combination with piperacillin and vancomycin. Serum levels of amikacin were measured on days 1, 3, 6 and 10, and 30 min, 60 min and 180 min after the end of the infusion. RESULTS: All patients responded favourably to the antibiotic therapy. Sixty-two kinetics were performed: peak amikacin concentrations measured (30 min after 30-min infusion) on day 1 averaged 43.7 micrograms/mL (+/- 13.8). A significant increase in peak serum concentrations was observed during the treatment (day 3 vs day 10) without change in the trough serum concentrations. The volumes of distribution were considerably important in these granulocytopenic children and there was a large inter and intra-patient variability; the elimination half-life of the amikacin was short (1.45 h). There was no significant nephrotoxicity in any patient. CONCLUSION: The use of single daily dose amikacin in combination with a broad spectrum beta-lactam antibiotic and vancomycin was efficient and safe in febrile granulocytopenic children. The simulation of the amikacin behaviour in the deep compartment should be evaluated; in fact, it might reflect better accumulation of the drug than serum concentrations.


Asunto(s)
Amicacina/farmacocinética , Amicacina/uso terapéutico , Antibacterianos/farmacocinética , Antibacterianos/uso terapéutico , Fiebre/complicaciones , Neutropenia/tratamiento farmacológico , Adolescente , Amicacina/administración & dosificación , Amicacina/sangre , Antibacterianos/administración & dosificación , Antibacterianos/sangre , Niño , Preescolar , Quimioterapia Combinada , Humanos , Lactante , Neutropenia/complicaciones , Penicilinas/administración & dosificación , Penicilinas/uso terapéutico , Piperacilina/administración & dosificación , Piperacilina/uso terapéutico , Vancomicina/administración & dosificación , Vancomicina/uso terapéutico
12.
Eur J Cell Biol ; 70(2): 157-64, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8793388

RESUMEN

Mechanical loading of cells is of fundamental relevance in physiological processes and induces several functional responses in cells. Integrins, a family of adhesion receptors, which are responsible for the interaction with the extracellular matrix, may play a role in transmission of mechanical signals into cells. The osteogenic cell line U-2 OS expresses different integrin subunits which are uniformly distributed over the cell surface. We applied defined physical forces on individual integrin receptor subunits using paramagnetic microbeads coated with anti-integrin antibodies. Application of an inhomogeneous magnetic field consequently leads to a mechanical stress on the receptor. Intracellular Ca2+ increased when the alpha 2 or the beta 1 integrin subunits were stressed, whereas mechanical loading of the transferrin receptor had a significantly lower effect. This result indicates that forces specifically exerted to individual integrin receptors induce signal transduction pathways.


Asunto(s)
Calcio/metabolismo , Integrinas/química , Magnetismo , Osteoblastos/metabolismo , Fragmentos de Péptidos/química , Humanos , Microesferas , Osteosarcoma/metabolismo , Estrés Mecánico , Células Tumorales Cultivadas
13.
Ann Pharm Fr ; 54(6): 263-7, 1996.
Artículo en Francés | MEDLINE | ID: mdl-9008900

RESUMEN

Knowing long term total parenteral nutrition (TPN) can bring 12 micrograms/kg/day as barium contamination, we investigated the barium ability to give the same bone toxicity as observed in patients' underlying TPN. A preliminary study carried out on 21 rats allowed us to calculate the bioavailability of barium chloride (50%) with doses fixed at 1 mg/kg for the intravenous route and 10 mg/kg for the oral route. As it is very difficult to feed rats parenterally for more than 30 days, we decided to give barium chloride orally. Twenty rats received 48 micrograms/kg/day barium chloride during 4 months. The barium plasma and bone levels were not statistically different between the control group and the tested group. The femurs and tibias were removed for analysis, carried out by different fixation and coloration techniques. No anomalies could be detected in the treated group concerning main bone parameters that are disturbed in patients' underlying TPN.


Asunto(s)
Compuestos de Bario/farmacocinética , Compuestos de Bario/envenenamiento , Huesos/efectos de los fármacos , Cloruros/farmacocinética , Cloruros/envenenamiento , Administración Oral , Animales , Compuestos de Bario/administración & dosificación , Disponibilidad Biológica , Huesos/metabolismo , Cloruros/administración & dosificación , Inyecciones Intravenosas , Masculino , Ratas , Ratas Sprague-Dawley
14.
Arch Androl ; 35(3): 247-59, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8585780

RESUMEN

The role of retinoids in the regulation of epididymal fluid protein expression was investigated. We compared the patterns of two-dimensional electrophoretic gels of proteins from luminal fluids, cytosols and spermatozoa (from control rats only) of control, retinoid-depleted, retinoid-depleted retinoic acid-complemented and retinoid-depleted testosterone-supplemented rats. This study compared the luminal fluid patterns from the 4 diets and observed 13 proteins whose expression was dependent on nutritional status. Eight were either absent or very weakly expressed in retinoid-depleted animals only, while their presence was obvious in control rats and in the retinoid-deficient retinoic acid- and testosterone-complemented groups. The expression of 8 proteins was greatly enhanced in retinoid-depleted testosterone-supplemented fluids as compared to control fluids. Five of the regulated proteins seemed to be captured by spermatozoa as they were observed in sperm protein patterns of control rats. These results clearly show that the synthesis of several epididymal proteins is influenced by retinoids. Since testosterone-supplemented animals on retinoid-free diet elicited the same response as retinol and retinoic acid ones, testosterone is likely to be the mediator of retinoid action on epididymal protein synthesis. Nevertheless, the observation of one protein whose expression is stimulated by retinoic acid only and is totally independent of testosterone also favors the direct influence of this retinoid.


Asunto(s)
Epidídimo/metabolismo , Proteínas/metabolismo , Retinoides/farmacología , Animales , Electroforesis en Gel Bidimensional , Epidídimo/química , Masculino , Proteínas/análisis , Ratas , Ratas Sprague-Dawley , Hormonas Testiculares/análisis , Hormonas Testiculares/metabolismo , Testosterona/farmacología , Tretinoina/farmacología , Vitamina A/sangre
15.
Respiration ; 61 Suppl 1: 16-9, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7800966

RESUMEN

This population-based prospective cohort study compared the risk of recurrent infections in children attending family day care (< or = 3 children per family), small (10-20 children) day-care centers (DCCs), and large (> or = 40 children) DCCs. The parents of a total of 1,242 children participated in the study (97% of the families initially contacted). An infectious episode was defined as the acute occurrence of a new symptom lasting for at least 48 h and resulting in specific treatment. Two episodes were counted as such only if they were separated by a symptom-free week. Surveillance was under the responsibility of a nursing director and was similar for all three types of DCCs. During the 8.5-month follow-up period, 3,639 infectious episodes were recorded. Compared to those in family day-care, children attending small DCCs presented a higher risk for > or = 6 total infectious episodes [odds ratio (OR) = 2.4; 95% confidence interval (CI) = 1.6-3.7]; > or = 5 upper respiratory tract infections (OR = 2.2; 95% CI = 1.4-3.4); > or = 2 episodes of otitis media (OR = 2.6; 95% CI = 1.0-2.6); > or = 2 episodes of conjunctivitis (OR = 4.1; 95% CI = 2.1-8.2); and > or = 2 episodes of croup (OR = 4.1; 95% CI = 1.6-10.9). The risk for children attending large DCCs was intermediate between those in family day care and those in small DCCs.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Guarderías Infantiles , Infecciones/epidemiología , Cuidado del Niño , Preescolar , Estudios de Cohortes , Conjuntivitis/epidemiología , Francia/epidemiología , Gastroenteritis/epidemiología , Humanos , Lactante , Cuidado del Lactante , Otitis Media/epidemiología , Recurrencia , Infecciones del Sistema Respiratorio/epidemiología , Factores de Riesgo , Estaciones del Año
16.
Respiration ; 61 Suppl 1: 24-31, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7800968

RESUMEN

Viral investigations were performed during 4 winter seasons (88/89, 89/90, 92/93, 93/94) in children attending day-care centers (DCCs) in the Rhône Département in eastern France. Over the total observation period of 4 winter seasons, 780 children were screened with a nasal swab for the presence of viruses. Of those, 230 (29.5%) had a positive viral culture. The viruses identified were respiratory syncytial virus (RSV), influenza A and B virus, parainfluenza virus, coronavirus, rhinovirus, adenovirus and enterovirus. During that time, 83 epidemic events in 47 DCC were recorded. A particular virus was judged to be causally related to an epidemic if the identical virus was isolated in > or = 3 children during the same outbreak of respiratory diseases. Thus, in 51 cases (61.4%) of all epidemics, the following viruses were responsible for an epidemic: RSV (n = 23), coronavirus (n = 10) (only during the season of 1993-1994), influenza A virus (n = 6), rhinovirus (n = 4), enterovirus (n = 4), adenovirus (n = 3) and parainfluenza virus (n = 1). Except for the somewhat surprising accumulation of coronavirus epidemics during the winter of 1993-1994, there were only minor seasonal variations from one year to another. As expected, RSV accounted for about one third of all respiratory tract infections in children attending DCCs and was therefore the most important single causative agent. These results are compared with data from children who did not attend a DCC and were cared for in a private practice.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Adyuvantes Inmunológicos/uso terapéutico , Bacterias , Extractos Celulares , Guarderías Infantiles , Brotes de Enfermedades , Virosis/epidemiología , Virosis/prevención & control , Virus/aislamiento & purificación , Niño , Preescolar , Francia/epidemiología , Humanos , Lactante , Factores de Riesgo , Estaciones del Año , Virosis/microbiología
17.
Oncol Res ; 6(7): 291-301, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7865904

RESUMEN

Bisantrene, mitoxantrone, and anthracyclines are anthracene derivatives that interact with DNA and are used for the treatment of cancers. The mechanisms of resistance to bisantrene are unknown. Here we show that cells that overexpress low levels of P-glycoprotein or are transfected with human MDR1 have approximately 10-fold greater resistance to bisantrene compared to vinblastine, doxorubicin, or colchicine. Furthermore, bisantrene can be used to select for high-level P-glycoprotein-mediated multiple drug resistance in a human colon carcinoma cell line, LS 174T, and the drug blocks photoaffinity labeling of P-glycoprotein. The data suggest that bisantrene is an excellent substrate for P-glycoprotein. These findings could influence subsequent clinical evaluation of bisantrene for the treatment of cancer.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Antibióticos Antineoplásicos/farmacología , Antineoplásicos/farmacología , Resistencia a Múltiples Medicamentos , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/biosíntesis , Antracenos/farmacología , Secuencia de Bases , Bandeo Cromosómico , Cromosomas Humanos , Células Clonales , Neoplasias del Colon , Cartilla de ADN , Humanos , Hibridación Fluorescente in Situ , Células KB , Melanoma , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/metabolismo , Transfección , Células Tumorales Cultivadas
18.
Pediatr Infect Dis J ; 12(8): 648-52, 1993 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8414777

RESUMEN

A randomized, double blind, placebo-controlled clinical trial was performed in 423 children attending day-care centers to assess whether stimulating nonspecific immunity would reduce the incidence of recurrent infections. The drug used for the trial (Imocur) is an extract obtained from eight different species of bacteria. At the end of the total follow-up period (3 months with treatment and 4.5 months without), the risk for > or = 4 episodes of upper respiratory infections was not significantly lower in the treated group than in the placebo group (26.7% vs. 33.8%, relative risk, 0.79; 95% confidence interval, 0.59 to 1.06). In an exploratory analysis limited to the 3-month treatment period, however, we observed a 48% reduction in the risk of presenting > or = 3 episodes of upper respiratory infections: 9.5% vs. 18.3%, respectively, in the treatment group and the placebo group (relative risk, 0.52; 95% confidence interval, 0.31 to 0.86). Similar results were found for the risk of > or = 1 episode of gastroenteritis. We also observed a strong correlation between the drug efficacy and age; this observation is coherent with the underlying pathophysiologic model in which the immune system matures with age.


Asunto(s)
Adyuvantes Inmunológicos/uso terapéutico , Bacterias , Extractos Celulares , Guarderías Infantiles , Gastroenteritis/prevención & control , Infecciones del Sistema Respiratorio/prevención & control , Adyuvantes Inmunológicos/efectos adversos , Factores de Edad , Formación de Anticuerpos , Preescolar , Método Doble Ciego , Femenino , Gastroenteritis/inmunología , Humanos , Lactante , Masculino , Recurrencia , Infecciones del Sistema Respiratorio/inmunología , Riesgo
19.
J Med Chem ; 36(15): 2098-101, 1993 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-8340913

RESUMEN

The selective phosphorylation of bisantrene (1) affords bis(phosphonoguanidinic acid) 6, a prodrug with enhanced aqueous solubility (as sodium salt 7) at physiological pH. Unlike 1, in a rat tail vein model, no precipitation was observed when bis(phosphonoguanidinic acid) 6 was injected. While in rats 6 hydrolyzed to monophosphonoguanidinic acid 9 with a half-life of ca. 12 min., complete hydrolysis to bisantrene required several hours. The corresponding monophosphonoguanidinic acid 9 was synthesized from bisantrene and also showed good solubility and antitumor activity. While the antitumor activities of 6 in mice were comparable to bisantrene against B-16 melanoma and P-388 and L-1210 leukemias, it was inactive in vitro vs several tumor cell types. Thus, its activity in vivo resulted from its ability to serve as a prodrug for bisantrene.


Asunto(s)
Antibióticos Antineoplásicos/síntesis química , Profármacos/síntesis química , Animales , Antracenos/síntesis química , Antracenos/farmacología , Leucemia P388/tratamiento farmacológico , Melanoma Experimental/tratamiento farmacológico , Ratones , Ratas , Ratas Sprague-Dawley
20.
Cancer Res ; 53(14): 3336-42, 1993 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-8324745

RESUMEN

The calicheamicin family of antitumor antibiotics are capable of producing double-stranded DNA breaks at sub-picomolar concentrations. Their potency suggested that the calicheamicins would be excellent candidates for targeted delivery and a hydrazide prepared from the most potent and abundant of the naturally occurring derivative, gamma 1I, was linked to oxidized sugars on CT-M-01, an internalizing anti-polyepithelial mucin antibody. The conjugates retained the immunoreactivity of the unmodified antibody and were specifically cytotoxic toward antigen positive tumor cells in vitro and in vivo. Hydrazide analogues of less potent calicheamicin derivatives were also prepared and conjugated to CT-M-01. Comparison of the therapeutic efficacy of the conjugates against the MX-1 xenograft tumor implanted s.c. in nude mice showed that conjugates of derivatives missing the rhamnose, a sugar residue that is part of the DNA binding region of the drug, were not as promising as antitumor therapies. However, conjugates of two derivatives, alpha 3I and N-acetyl-gamma 1I, in which the rhamnose residue is present but the amino sugar residue of the parent drug is either missing or modified, significantly inhibited tumor growth over a 4-fold dose range and produced long-term tumor-free survivors. Sterically hindering methyl groups adjacent to the disulfide in the linker further increased the therapeutic window of these potent conjugates.


Asunto(s)
Antibacterianos/farmacología , Antibióticos Antineoplásicos/farmacología , Aminoglicósidos , Animales , Antibacterianos/química , Antibióticos Antineoplásicos/química , Anticuerpos Monoclonales , Neoplasias de la Mama/tratamiento farmacológico , Ensayos de Selección de Medicamentos Antitumorales , Estudios de Factibilidad , Femenino , Humanos , Leucemia P388/tratamiento farmacológico , Ratones , Ratones Desnudos , Estructura Molecular , Relación Estructura-Actividad , Células Tumorales Cultivadas
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