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1.
Ann Oncol ; 25(8): 1656-63, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24827126

RESUMEN

BACKGROUND: To establish the maximum tolerated dose, determine safety/tolerability and evaluate the pharmacokinetics and preliminary efficacy of olaparib in combination with cisplatin in patients with advanced solid tumors. PATIENTS AND METHODS: Patients aged ≥ 18 years with advanced solid tumors, who had progressed on standard treatment, were assigned to a treatment cohort and received oral olaparib [50-200 mg twice daily (bid); 21-day cycle] continuously or intermittently (days 1-5 or 1-10) in combination with cisplatin (60-75 mg/m(2) intravenously) on day 1 of each cycle. RESULTS: Dose-limiting toxicities (DLTs) of grade 3 neutropenia (cisplatin 75 mg/m(2) with continuous olaparib 100 mg bid or 200 mg bid; n = 1 each) and grade 3 lipase elevation (cisplatin 75 mg/m(2) with olaparib 100 mg bid days 1-10 or 50 mg bid days 1-5; n = 1 each) were reported. Olaparib and cisplatin doses were subsequently reduced to 50 mg bid days 1-5 and 60 mg/m(2), respectively; no DLTs were reported for patients receiving this regimen. The most frequent grade ≥ 3 adverse events were neutropenia (16.7%), anemia (9.3%) and leucopenia (9.3%). Thirty patients (55.6%) received colony-stimulating factors for hematologic support. The overall objective response rate was 41% for patients with measurable disease, and 43% and 71% among patients with a BRCA1/2 mutation who had ovarian and breast cancer, respectively. CONCLUSIONS: Olaparib in combination with cisplatin 75 mg/m(2) was not considered tolerable; intermittent olaparib (50 mg bid, days 1-5) with cisplatin 60 mg/m(2) improved tolerability. Promising antitumor activity in patients with germline BRCA1/2 mutations was observed and warrants further investigation.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Cisplatino/administración & dosificación , Neoplasias/tratamiento farmacológico , Neoplasias Ováricas/tratamiento farmacológico , Ftalazinas/administración & dosificación , Piperazinas/administración & dosificación , Adulto , Anciano , Neoplasias de la Mama/patología , Cisplatino/efectos adversos , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/patología , Neoplasias Ováricas/patología , Ftalazinas/efectos adversos , Piperazinas/efectos adversos , Resultado del Tratamiento
2.
Ann Oncol ; 22(2): 468-71, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20624787

RESUMEN

BACKGROUND: Children with recurrent or refractory malignant lymphoma generally have a poor prognosis. There is a need for new active drug combinations for this high-risk group of patients. PATIENTS AND METHODS: This study evaluated the activity and toxicity of the methotrexate, ifosfamide, etoposide and dexamethasone (MIED) regimen for childhood refractory/recurrent non-Hodgkin's lymphoma (NHL) or Hodgkin's lymphoma (HL). From 1991 through 2006, 62 children with refractory/recurrent NHL (n = 24) or HL (n = 38) received one to six cycles of MIED. Based on MIED response, intensification with hematopoietic stem cell transplantation (HSCT) was considered. RESULTS: There were 10 complete (CR) and 5 partial responses (PR) among the 24 children with NHL [combined response rate, 63%; 95% confidence interval (CI) 38% to 73%]. There were 13 CR and 18 PR among the 37 assessable children with HL (combined response rate, 84%; 95% CI, 68% to 94%). Although 59% courses were associated with grade IV neutropenia, treatment was well tolerated and without toxic deaths. CONCLUSIONS: MIED is an effective regimen for refractory/recurrent childhood malignant lymphoma, permitting a bridge to intensification therapy with HSCT.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Enfermedad de Hodgkin/tratamiento farmacológico , Linfoma no Hodgkin/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Niño , Dexametasona/administración & dosificación , Etopósido/administración & dosificación , Enfermedad de Hodgkin/patología , Humanos , Ifosfamida/administración & dosificación , Linfoma no Hodgkin/patología , Metotrexato/administración & dosificación , Recurrencia , Terapia Recuperativa
3.
J Child Orthop ; 13(1): 73-81, 2019 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-30838079

RESUMEN

PURPOSE: Spastic cerebral palsy (CP) is characterized by four neuromuscular deficits: weakness, short muscle-tendon unit, muscle spasticity and impaired selective motor control (SMC). We examined the influence of impaired SMC on gait in children with bilateral spastic CP. Delineating the influence of neuromuscular deficits on gait abnormalities can guide surgical and therapeutic interventions to reduce long-term debilitating effects of CP. METHODS: The relationship between impaired SMC and gait was assessed using multivariate linear regression analysis of Selective Control Assessment of the Lower Extremity (SCALE) in relation to stance phase knee flexion and temporal-spatial gait parameters calculated using 3D kinematics for 57 children with bilateral spastic CP, ages seven to 11 years. RESULTS: Mean SCALE values were 5.8 (0 to 10, sd 3.0) and 5.7 (0 to 10, sd 2.9) for right and left legs, respectively. Multivariate linear regression models, including right and left SCALE and height, significantly predicted right and left knee flexion at initial contact (R = 0.479, p = 0.003; R = 0.452, p = 0.007, respectively) and right and left knee flexion in midstance (R = 0.428, p = 0.013; R = 0.407, p = 0.022, respectively). The model significantly predicted right and left step length (R = 0.645, p = 0.000; R = 0.523, p = 0.001, respectively) and predicted gait velocity (R = 0.444, p = 0.008). The model including SCALE did not predict step width. CONCLUSION: Results indicate impaired SMC predicts increased knee flexion at initial contact, and reduces step length and velocity. Understanding the influence of impaired SMC on gait can inform decisions regarding therapy and surgery, such as hamstring lengthening. LEVEL OF EVIDENCE: Level II Retrospective Study.

4.
Food Chem Toxicol ; 45(10): 2047-56, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17583405

RESUMEN

This study was conducted to determine the relative dermal bioavailability (absorption), distribution, metabolism, and excretion (ADME) of diisopropanolamine (DIPA), an alcohol amine used in a number of industrial and personal care products. Groups of 4 female Fischer 344 rats received either a single bolus i.v. dose of 19.0mg/kg (14)C-DIPA in water or a dermal application of 19.5mg/kg (14)C-DIPA in acetone to an area of 1cm(2) on the back and covered with a bandage. Time-course blood and excreta were collected and radioactivity determined. Urine was analyzed for DIPA and monoisopropanolamine (MIPA). Following i.v. administration, DIPA was rapidly cleared from the plasma and excreted into urine in a biexponential manner (t(1/2alpha), 0.4h; t(1/2beta), 2.9h). The levels of radioactivity in plasma dropped below the limit of detection 12h post-dosing. A total of 97+/-4% of the dose was actively excreted in urine by kidney, most ( approximately 71%) within 6h of dosing, virtually all as parent compound; renal clearance exceeded the glomerular filtration rate. Following dermal application, approximately 20% of the dose was absorbed in 48 h with the steady-state penetration rate of approximately 0.2%/h. Most (14.4%) of the applied radioactivity was excreted in urine at a relatively constant rate due to the presence of large amount of the (14)C-DIPA at the application site. Fecal elimination was <0.2% of the dose. The absorbed DIPA did not accumulate in tissues; only approximately 0.1% of the administered dose was found in liver and kidney. The absolute systemic dermal bioavailability (dose corrected AUC(dermal)/AUC(i.v.)) of (14)C-DIPA was 12%. The ADME of DIPA contrasts that of its diethanol analogue, diethanolamine, which displays a broad spectrum of toxicity in rats and mice. Toxicologically significant concentrations of DIPA are unlikely to be achieved in the systemic circulation and/or tissues as a result of repeated dermal application of products containing DIPA due to slow absorption from the skin, rapid unchanged elimination in urine, and majority of the products contain

Asunto(s)
Propanolaminas/farmacocinética , Animales , Área Bajo la Curva , Dióxido de Carbono/metabolismo , Interpretación Estadística de Datos , Eritrocitos/efectos de los fármacos , Eritrocitos/metabolismo , Heces/química , Femenino , Semivida , Inyecciones Intradérmicas , Inyecciones Intravenosas , Propanolaminas/administración & dosificación , Ratas , Ratas Endogámicas F344 , Absorción Cutánea
5.
Mar Genomics ; 24 Pt 2: 177-83, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26472700

RESUMEN

Opsins--G-protein coupled receptors involved in photoreception--have been extensively studied in the animal kingdom. The present work provides new insights into opsin-based photoreception and photoreceptor cell evolution with a first analysis of opsin sequence data for a major deuterostome clade, the Ambulacraria. Systematic data analysis, including for the first time hemichordate opsin sequences and an expanded echinoderm dataset, led to a robust opsin phylogeny for this cornerstone superphylum. Multiple genomic and transcriptomic resources were surveyed to cover each class of Hemichordata and Echinodermata. In total, 119 ambulacrarian opsin sequences were found, 22 new sequences in hemichordates and 97 in echinoderms (including 67 new sequences). We framed the ambulacrarian opsin repertoire within eumetazoan diversity by including selected reference opsins from non-ambulacrarians. Our findings corroborate the presence of all major ancestral bilaterian opsin groups in Ambulacraria. Furthermore, we identified two opsin groups specific to echinoderms. In conclusion, a molecular phylogenetic framework for investigating light-perception and photobiological behaviors in marine deuterostomes has been obtained.


Asunto(s)
Cordados no Vertebrados/genética , Equinodermos/genética , Evolución Molecular , Opsinas/metabolismo , Filogenia , Secuencia de Aminoácidos , Animales , Regulación de la Expresión Génica , Modelos Moleculares , Datos de Secuencia Molecular , Opsinas/genética , Conformación Proteica
6.
J Clin Endocrinol Metab ; 43(6): 1402-5, 1976 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1002824

RESUMEN

Urinary excretions of progesterone (P) during normal menstrual cycle have been measured by radioimmunoassay. The excretion pattern mimics that of plasma P. Measurements of P in a single voided urine may be a reliable substitute for plasma analyses in the evaluation of ovulation and corpus luteal function.


Asunto(s)
Cuerpo Lúteo/fisiología , Menstruación , Ovulación , Progesterona/orina , Femenino , Humanos
7.
FEBS Lett ; 430(1-2): 1-11, 1998 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-9678585

RESUMEN

Protein kinases catalyse phospho transfer reactions from ATP to serine, threonine or tyrosine residues in target substrates and provide key mechanisms for control of cellular signalling processes. The crystal structures of 12 protein kinases are now known. These include structures of kinases in the active state in ternary complexes with ATP (or analogues) and inhibitor or peptide substrates (e.g. cyclic AMP dependent protein kinase, phosphorylase kinase and insulin receptor tyrosine kinase); kinases in both active and inactive states (e.g. CDK2/cyclin A, insulin receptor tyrosine kinase and MAPK); kinases in the active state (e.g. casein kinase 1, Lck); and kinases in inactive states (e.g. twitchin kinase, calcium calmodulin kinase 1, FGF receptor kinase, c-Src and Hck). This paper summarises the detailed information obtained with active phosphorylase kinase ternary complex and reviews the results with reference to other kinase structures for insights into mechanisms for substrate recognition and control.


Asunto(s)
Fosforilasa Quinasa/metabolismo , Proteínas Quinasas/metabolismo , Adenosina Trifosfato/metabolismo , Sitios de Unión , Catálisis , Activación Enzimática , Modelos Moleculares , Péptidos/metabolismo , Fosforilasa Quinasa/química , Fosforilasas/metabolismo , Fosforilación , Conformación Proteica , Especificidad por Sustrato
8.
Antioxid Redox Signal ; 5(4): 359-66, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-13678522

RESUMEN

DsbA is the primary catalyst of disulfide bond formation in the periplasm of gram-negative bacteria. Numerous theoretical and experimental studies have been undertaken to determine the molecular mechanisms by which DsbA acts as a potent oxidant, whereas the homologous cytoplasmic protein, thioredoxin, acts as a reductant. Many of these studies have focused on the nature of the two residues that lie between the active-site cysteines. Although these are clearly important, they are not solely responsible for the differences in activity between these thiol-disulfide oxidoreductases. Q97 in the helical domain of E. coli DsbA has been implicated in influencing the redox potential of E. coli DsbA. In V. cholerae DsbA, the analogous residue is H94. In this study, the effect of H94 on the oxidase activity of DsbA is examined, along with the role of the conserved cis-proline residue P149. The DsbA mutant H94L shows a nearly fourfold increase in activity over the wild-type enzyme. To our knowledge, this is the first time an increase in the normal activity of a thiol-disulfide oxidoreductase has been reported. Potential reasons for this increase in activity are discussed.


Asunto(s)
Histidina/metabolismo , Prolina/metabolismo , Proteína Disulfuro Isomerasas/química , Proteína Disulfuro Isomerasas/metabolismo , Vibrio cholerae/enzimología , Histidina/genética , Concentración de Iones de Hidrógeno , Prolina/genética , Proteína Disulfuro Isomerasas/genética , Proteína Disulfuro Isomerasas/aislamiento & purificación , Vibrio cholerae/genética , Vibrio cholerae/crecimiento & desarrollo
9.
Microbes Infect ; 3(10): 789-97, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11580973

RESUMEN

Glucans are fungal cell wall polysaccharides which stimulate innate immune responses. We determined the minimum unit ligand that would bind to glucan receptors on human U937 cells using laminarin-derived pentaose, hexaose, and heptaose glucan polymers. When U937 membranes were pretreated with the oligosaccharides and passed over a glucan surface, only the heptasaccharide inhibited the interaction of glucan with membrane receptors at a K(d) of 31 microM (95% CI 20-48 microM) and 100% inhibition. However, the glucan heptasaccharide did not stimulate U937 monocyte NFkappaB signaling, nor did it increase survival in a murine model of polymicrobial sepsis. Laminarin, a larger and more complex glucan polymer (M(w) = 7700 g/mol), only partially inhibited binding (61 +/- 4%) at a K(d) of 2.6 microM (99% CI 1.7-4.2 microM) with characteristics of a single binding site. These results indicate that a heptasaccharide is the smallest unit ligand recognized by macrophage glucan receptors. The data also indicate the presence of at least two glucan-binding sites on U937 cells and that the binding sites on human monocyte/macrophages can discriminate between glucan polymers. The heptasaccharide and laminarin were receptor antagonists, but they were not receptor agonists with respect to activation of NFkappaB-dependent signaling pathways or protection against experimental sepsis.


Asunto(s)
Glucanos/metabolismo , Monocitos/metabolismo , Polisacáridos/metabolismo , Receptores Inmunológicos/metabolismo , Animales , Sitios de Unión , Relación Dosis-Respuesta a Droga , Humanos , Ligandos , Masculino , Ratones , Ratones Pelados , Ratones Endogámicos ICR , Monocitos/efectos de los fármacos , FN-kappa B/metabolismo , Polisacáridos/inmunología , Polisacáridos/farmacología , Unión Proteica , Receptores Inmunológicos/efectos de los fármacos , Sepsis/inmunología , Células U937
10.
Am J Med ; 69(1): 43-9, 1980 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7386507

RESUMEN

In 47 patients with disorders of the gastrointestinal tract, the bioavailability of digoxin tablets was assessed by measuring the area under the serum concentration-time curve (AUC) after the oral administration of single 0.5 mg doses. In 13 or 14 patients who had undergone a previous ileal resection, in 10 of 10 patients with sprue and in 14 of 14 patients with a variety of disorders of the gastrointestinal tract, digoxin absorption was normal despite marked steatorrhea in many. A patient with extensive jejunal and ileal resection, and inflammation of the remaining small bowel,was the sole exception. Impaired digoxin bioavailability was found in five of nine patients who had undergone jejunoileal bypass procedures (bypass patients. A strong correlation was noted between the length of jejunum remaining in continuity and the AUC (r = 0.86, p less than 0.01). Two of three bypass patients also showed decreased absorption of more rapidly dissolving tablets or an elixir. Digoxin bioavailability correlated significantly with and 2 hour serum xylose levels but not with urinary xylose excretion, fecal fat or the Schilling test result. The findings are consistent with the role of the upper small bowel as the predominant site of digoxin absorption as well as the reserve function of the ileum in the event of jejunal dysfunction or bypass.


Asunto(s)
Digoxina/metabolismo , Enfermedades Gastrointestinales/metabolismo , Adulto , Anciano , Disponibilidad Biológica , Enfermedad Celíaca/metabolismo , Femenino , Humanos , Íleon/fisiología , Absorción Intestinal , Yeyuno/fisiología , Masculino , Persona de Mediana Edad , Síndromes Posgastrectomía/metabolismo , Xilosa/metabolismo
11.
Pediatrics ; 58(5): 722-9, 1976 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-980604

RESUMEN

The blood pressures and pulse rates of 257 normal full-term infants and their mothers were measured two to four days after birth. Birthweight was correlated with systolic (P=.038), but not with diastolic blood pressure. Infants who were asleep had significantly lower systolic and diastolic blood pressure than infants who were awake (P less than .001). Sex, body length, and feedings did not appear to influence infant's blood pressure nor did the anesthesia given to the mothers. Maternal diastolic pressure correlated with infant's diastolic pressure (regression coefficient, .128) (P less than .01), whereas for systolic pressure the regression coefficient between maternal and infant pressure was .085 (P=NS). The aggregation between the diastolic blood pressures of infants and mothers was not influenced by birthweight, age of the mother, or medication administered to the mother. The pulse rates of black infants were significantly higher than those of white infants (P less than .002). There was no correlation between the pulse rates and blood pressures in infants.


Asunto(s)
Presión Sanguínea , Familia , Recién Nacido , Análisis de Varianza , Anestesia Obstétrica , Peso al Nacer , Peso Corporal , Etnicidad , Femenino , Humanos , Masculino , Embarazo , Pulso Arterial , Sueño , Vigilia
12.
Am J Cardiol ; 63(9): 594-8, 1989 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-2919563

RESUMEN

The feasibility and potential adverse effects of using intraoperative transesophageal echocardiography (TEE) in 19 children ages 7.5 to 16 years undergoing surgical repair of a variety of congenital heart defects were evaluated. The ability of TEE to assess the adequacy of surgical repair as well as left ventricular function and wall motion abnormalities in this setting was also examined. Intraoperative transesophageal 2-dimensional and Doppler evaluation, and, in selected patients, echo-contrast and color flow imaging, were performed with either a 3.5- or 5.0-MHz phased array probe mounted within the tip of a flexible gastroscope. Probe insertion was successful in 18 of 19 patients. Fiberoptic endoscopy (9 patients) and autopsy (1 patient--cardiac donor) performed within 24 hours of surgery demonstrated no significant esophageal abnormalities. Intraoperative wall motion abnormalities were identified in 8 patients but did not persist after the operation. An adequate surgical repair was demonstrated by contrast and color flow imaging in most patients. Microcavitation was detected in 6 patients for greater than 5 minutes after a standard debubbling procedure. No patient displayed any adverse neurologic effects. It is concluded that, with the currently available probes, intraoperative TEE can be performed safely and reliably in children as young as 7.5 years of age. The procedure provides valuable information regarding wall motion abnormalities, cardiac function and the adequacy of surgical repair.


Asunto(s)
Ecocardiografía/métodos , Cardiopatías Congénitas/cirugía , Cuidados Intraoperatorios/métodos , Adolescente , Niño , Estudios de Factibilidad , Humanos , Contracción Miocárdica , Factores de Riesgo
13.
AIDS Res Hum Retroviruses ; 8(3): 395-402, 1992 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1571198

RESUMEN

Simian immunodeficiency virus (SIV) is a designation for a group of related but unique lentiviruses identified in several primate species. A viral isolate from a rhesus macaque (i.e., SIVmac) causes a fatal AIDS-like disease in experimentally infected macaques, and several infectious molecular clones of this virus have been characterized. This report presents the complete nucleotide sequence of molecularly cloned SIVmac1A11, and comparisons are made with the sequence of molecularly cloned SIVmac239. SIVmac1A11 has delayed replication kinetics in lymphoid cells but replicates as well as uncloned SIVmac in macrophage cultures. Macaques infected with virus from the SIVmac1A11 clone develop antiviral antibodies, but virus does not persist in peripheral blood mononuclear cells and no disease signs are observed. SIVmac239 infects lymphoid cells, shows restricted replication in cultured macrophages, and establishes a persistent infection in animals that leads to a fatal AIDS-like disease. Both viruses are about 98% homologous at the nucleotide sequence level. In SIVmac1A11, the vpr gene as well as the transmembrane domain of env are prematurely truncated, whereas the nef gene of SIVmac239 is prematurely truncated. Sequence differences are also noted in variable region 1 (V1) in the surface domain of the env gene. The potential implications of these and other sequence differences are discussed with respect to the phenotypes of both viruses. This animal model is critically important for investigating the roles of specific viral genes in viral/host interactions that cannot be studied in individuals infected with the human immunodeficiency virus (HIV).


Asunto(s)
Virus de la Inmunodeficiencia de los Simios/patogenicidad , Secuencia de Aminoácidos , Animales , Clonación Molecular , Genes Virales/genética , Genes Virales/fisiología , Datos de Secuencia Molecular , Homología de Secuencia de Ácido Nucleico , Virus de la Inmunodeficiencia de los Simios/genética
14.
J Cancer Res Clin Oncol ; 123(7): 402-6, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9260593

RESUMEN

Renal cell carcinoma contains significantly lower concentrations of the lysosomal cysteine proteases, cathepsins B, C, H, L and S, than does normal kidney, as shown by several methods, such as activity determination, enzyme-linked immunosorbent assay, immunoblotting and immunohistochemistry. The same low levels of enzyme activity and concentration have been determined in renal cell carcinoma metastases in the lung. Our results on the decreased concentration of cysteine peptidases at the protein level would seem to conflict with earlier results on an increased concentration of the cathepsin L mRNA in renal cell carcinoma.


Asunto(s)
Carcinoma de Células Renales/enzimología , Catepsinas/metabolismo , Neoplasias Renales/enzimología , Riñón/enzimología , Catepsina L , Precursores Enzimáticos/metabolismo , Humanos , Inmunohistoquímica , Lisosomas/enzimología , Células Tumorales Cultivadas
15.
J Appl Physiol (1985) ; 78(4): 1596-611, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7615475

RESUMEN

This paper presents a complete set of equations for a "first principles" mathematical model of road-cycling performance, including corrections for the effect of winds, tire pressure and wheel radius, altitude, relative humidity, rotational kinetic energy, drafting, and changed drag. The relevant physiological, biophysical, and environmental variables were measured in 41 experienced cyclists completing a 26-km road time trial. The correlation between actual and predicted times was 0.89 (P < or = 0.0001), with a mean difference of 0.74 min (1.73% of mean performance time) and a mean absolute difference of 1.65 min (3.87%). Multiple simulations were performed where model inputs were randomly varied using a normal distribution about the measured values with a SD equivalent to the estimated day-to-day variability or technical error of measurement in each of the inputs. This analysis yielded 95% confidence limits for the predicted times. The model suggests that the main physiological factors contributing to road-cycling performance are maximal O2 consumption, fractional utilization of maximal O2 consumption, mechanical efficiency, and projected frontal area. The model is then applied to some practical problems in road cycling: the effect of drafting, the advantage of using smaller front wheels, the effects of added mass, the importance of rotational kinetic energy, the effect of changes in drag due to changes in bicycle configuration, the normalization of performances under different conditions, and the limits of human performance.


Asunto(s)
Ciclismo/fisiología , Modelos Teóricos , Adolescente , Adulto , Fenómenos Biofísicos , Biofisica , Femenino , Humanos , Masculino , Consumo de Oxígeno
16.
Cancer Chemother Pharmacol ; 47(3): 199-205, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11320662

RESUMEN

PURPOSE: In preclinical studies, thioguanine (TG) has been shown to be more potent than the standard acute lymphoblastic leukemia (ALL) maintenance agent, mercaptopurine (MP), suggesting that TG may be more efficacious than MP in the treatment of childhood ALL. As part of a pilot trial in which TG was used in place of MP, we studied the plasma pharmacokinetics of oral TG and measured steady-state plasma and CSF TG concentrations during a continuous intravenous infusion (CIVI) in children with newly diagnosed standard-risk ALL. METHODS: Nine plasma samples were collected after each patient's first 60 mg/m2 oral TG dose during maintenance. CIVI TG (20 mg/m2/h over 24 h) was administered during the consolidation phase of therapy, and simultaneous plasma and CSF samples were collected near the end of the infusion. TG was measured by reverse-phase HPLC with ultraviolet detection. Erythrocyte TG nucleotide (TGN) concentrations were measured 7 days after a course of CIVI TG and prior to the start of each maintenance cycle. RESULTS: After oral TG (n = 35), the mean (+/- SD) peak plasma concentration was 0.46 +/- 0.68 microM and the AUC ranged from 0.18 to 9.5 microM.h (mean 1.5 microM.h). Mean steady-state plasma and CSF TG concentrations during CIVI (n = 33) were 2.7 and 0.5 microM, respectively. The mean (+/- SD) TG clearance was 935 +/- 463 ml/min per m2. Plasma TG concentrations did not correlate with erythrocyte TGN concentrations after oral or CIVI TG. The 8-OH-TG metabolite was detected in plasma and CSF. CONCLUSIONS: TG concentrations that are cytotoxic to human leukemia cell lines can be achieved in plasma after a 60 mg/m2 oral dose of TG and in plasma and CSF during CIVI of TG.


Asunto(s)
Antimetabolitos Antineoplásicos/farmacocinética , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Tioguanina/farmacocinética , Administración Oral , Antimetabolitos Antineoplásicos/líquido cefalorraquídeo , Antimetabolitos Antineoplásicos/uso terapéutico , Antimetabolitos Antineoplásicos/orina , Área Bajo la Curva , Cromatografía Líquida de Alta Presión/métodos , Eritrocitos/metabolismo , Humanos , Infusiones Intravenosas , Proyectos Piloto , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Tioguanina/líquido cefalorraquídeo , Tioguanina/uso terapéutico , Tioguanina/orina
17.
Steroids ; 31(3): 375-91, 1978 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-663976

RESUMEN

A radioimmunoassay method for urinary catechol estrogens is described; The specific nature of the antisera allows direct analyses of acid hydrolyzed urine. A LH-20 Sephadex column chromatography can be employed for individual determinations of 2-hydroxyestrone and 2-hydroxyestradiol. The excretion of catechol estrogens during menstrual cycles ranged from 14.48 to 50.15 microgram per 24 hours, whereas, during the last trimester of pregnancies, the values ranged from 129.30 to 1758. 20 microgram per 24 hours.


Asunto(s)
Estrona/análogos & derivados , Hidroxiestronas/orina , Tercer Trimestre del Embarazo , Especificidad de Anticuerpos , Ácido Ascórbico/farmacología , Reacciones Cruzadas , Estrógenos/orina , Femenino , Humanos , Hidroxiestronas/inmunología , Hidroxiestronas/aislamiento & purificación , Embarazo , Radioinmunoensayo/métodos , Temperatura
18.
Am J Sports Med ; 8(3): 208-11, 1980.
Artículo en Inglés | MEDLINE | ID: mdl-6769348

RESUMEN

A group of 10 patients (3 women and 7 men; 17 to 57 years old, average 23.9; mean, 21 years) was evaluated preoperatively and postoperatively following surgical repair with a modification of the Elmslie procedure (i.e., by using one-half of the tendinous portion of the peroneus brevis ligament to reconstruct the anterior and middle fasciculi of the lateral ligament). The patients were athletes who participated in bicycling, boxing, tennis, hockey, basketball, football, soccer, or a combination of sports. Each patient gave a history of spraining the ankle numerous times. Stress films were obtained preoperatively and postoperatively. The talar tilt was generally reduced in postoperative films (average preoperatively, 12.5 degrees; average postoperatively, 5.6 degrees). We conclude that the Elmslie procedure, as modified by Chrisman and Snook, is simpler to perform than the Watson-Jones procedure and has provided the majority of our patients with satisfactory results.


Asunto(s)
Traumatismos del Tobillo , Traumatismos en Atletas/cirugía , Esguinces y Distensiones/cirugía , Adolescente , Adulto , Tobillo/cirugía , Femenino , Humanos , Masculino , Métodos , Persona de Mediana Edad , Recurrencia
19.
Acta Cytol ; 26(3): 338-40, 1982.
Artículo en Inglés | MEDLINE | ID: mdl-6954816

RESUMEN

A case clinically diagnosed as Mollaret's meningitis is presented. The cytologic presentation of the cerebrospinal fluid is described, and the major clinical aspects and the differential diagnosis are briefly discussed. This is the first reported case of Mollaret's meningitis in Australia.


Asunto(s)
Líquido Cefalorraquídeo/citología , Meningitis Aséptica/líquido cefalorraquídeo , Meningitis/líquido cefalorraquídeo , Nucléolo Celular/ultraestructura , Núcleo Celular/ultraestructura , Citoplasma/ultraestructura , Endotelio/patología , Humanos , Linfocitos/ultraestructura , Masculino , Persona de Mediana Edad , Monocitos/ultraestructura , Neutrófilos/ultraestructura , Membrana Nuclear , Fagocitosis
20.
J Psychoactive Drugs ; 31(2): 145-54, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10437997

RESUMEN

Research on the relationship between methadone and alcohol has produced varying and sometimes contradictory results, such that being prescribed methadone has been associated with different patterns of drinking and degrees of problem drinking. Little is known about the mediating influence of sociocultural factors in relation to these variations. This article is an assessment of the nature and extent of alcohol use among a sample of people being prescribed methadone in a Glasgow housing estate, identifying factors which influenced alcohol use, and assessing the role of sociocultural factors. Data were collected through ethnographic methods and short self-completion questionnaire from 32 methadone clients. Typically, current problem drinking was not a feature of this sample. Most participants experimented with alcohol in their teenage years; however, their use of alcohol decreased to minimal or ended completely as they became increasingly involved with other drugs, especially opiates. Use of opiates became incompatible with use of alcohol for the following reasons: becoming an opiate user interrupts the typical process of becoming a "novice drinker" in adolescence; through a process of labeling and self-identification the "drug addict" both opts out of and is excluded from the mainstream drinking culture; if, despite these previous conditions, the opiate user does drink, adverse physical effects reported by the participants are sufficient to act at least as a partial deterrent to further use of alcohol. For most of the participants in the study, these three factors continue to influence current use of alcohol and in combination would appear to offer some explanation for the low levels of reported drinking.


Asunto(s)
Consumo de Bebidas Alcohólicas , Metadona/uso terapéutico , Adulto , Femenino , Dependencia de Heroína/rehabilitación , Vivienda , Humanos , Masculino , Escocia , Encuestas y Cuestionarios
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