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1.
Eur Radiol ; 26(9): 3046-53, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26801161

RESUMEN

OBJECTIVE: To determine inter-observer and inter-examination variability of manual attenuation measurements of the vertebrae in low-dose unenhanced chest computed tomography (CT). METHODS: Three hundred and sixty-seven lung cancer screening trial participants who underwent baseline and repeat unenhanced low-dose CT after 3 months because of an indeterminate lung nodule were included. The CT attenuation value of the first lumbar vertebrae (L1) was measured in all CTs by one observer to obtain inter-examination reliability. Six observers performed measurements in 100 randomly selected CTs to determine agreement with limits of agreement and Bland-Altman plots and reliability with intraclass correlation coefficients (ICCs). Reclassification analyses were performed using a threshold of 110 HU to define osteoporosis. RESULTS: Inter-examination reliability was excellent with an ICC of 0.92 (p < 0.001). Inter-examination limits of agreement ranged from -26 to 28 HU with a mean difference of 1 ± 14 HU. Inter-observer reliability ICCs ranged from 0.70 to 0.91. Inter-examination variability led to 11.2 % reclassification of participants and inter-observer variability led to 22.1 % reclassification. CONCLUSIONS: Vertebral attenuation values can be manually quantified with good to excellent inter-examination and inter-observer reliability on unenhanced low-dose chest CT. This information is valuable for early detection of osteoporosis on low-dose chest CT. KEY POINTS: • Vertebral attenuation values can be manually quantified on low-dose unenhanced CT reliably. • Vertebral attenuation measurements may be helpful in detecting subclinical low bone density. • This could become of importance in the detection of osteoporosis.


Asunto(s)
Vértebras Lumbares/fisiología , Neoplasias Pulmonares/diagnóstico por imagen , Osteoporosis/diagnóstico por imagen , Anciano , Detección Precoz del Cáncer , Femenino , Humanos , Vértebras Lumbares/efectos de la radiación , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Dosis de Radiación , Reproducibilidad de los Resultados , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos
2.
Diabetologia ; 56(8): 1826-34, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23653049

RESUMEN

AIMS/HYPOTHESIS: In vitro, insulin glargine (A21Gly,B31Arg,B32Arg human insulin) has an insulin receptor (IR) profile similar to that of human insulin, but a slightly higher affinity for the IGF-1 receptor (IGF1R). AspB10 human insulin (AspB10), [corrected] the only insulin analogue with proven carcinogenic activity, has a greater affinity for IGF1R and IR, and a prolonged IR occupancy time. The pharmacological and signalling profile of therapeutic and suprapharmacological doses of glargine were analysed in different tissues of rats, and compared with human insulin and AspB10. METHODS: Male Wistar rats were injected s.c. with human insulin or insulin analogue at doses of 1 to 200 U/kg, and the effects on blood glucose and the phosphorylation status of IR, IGF1R, Akt and extracellular signal-regulated protein kinase 1/2 in muscle, fat, liver and heart samples were investigated. RESULTS: Glargine, AspB10 and human insulin lowered blood glucose, with the onset of action delayed with glargine. Glargine treatment resulted in phosphorylation levels of IR and Akt that were comparable with those achieved with human insulin, although delayed in time in some tissues. AspB10 treatment resulted in at least twofold higher phosphorylation levels and significantly longer duration of IR and Akt phosphorylation in most tissues. None of the insulin treatments resulted in detectable IGF1R phosphorylation in muscle or heart tissue, whereas intravenous injection of IGF-1 increased IGF1R phosphorylation. CONCLUSIONS/INTERPRETATION: The IR signalling pattern of AspB10 in vivo is distinctly different from that of human insulin and insulin glargine, and might challenge the notion that activation of IGF1R plays a role in the observed carcinogenic effect of AspB10.


Asunto(s)
Insulina Aspart/farmacología , Insulina de Acción Prolongada/farmacología , Animales , Glucemia/efectos de los fármacos , Humanos , Insulina/análogos & derivados , Insulina/farmacología , Insulina Glargina , Masculino , Fosforilación/efectos de los fármacos , Ratas , Ratas Wistar , Receptor de Insulina/metabolismo
3.
Diabetes Obes Metab ; 15(4): 324-34, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23121319

RESUMEN

AIMS: Intensive glycaemic control in type 2 diabetes achieved by insulin is generally accompanied by body weight gain. This study was performed to emphasize the meaning of caloric analysis of urine and faeces for energy balance. METHODS: We measured energetic loss via urine and faeces during antihyperglycaemic treatment in male obese Zucker diabetic fatty (ZDF) rats. Rats were treated for 10 days with the sodium-glucose-linked transporter-2 (SGLT2) inhibitor AVE2268, with insulin glargine, with the GLP-1 receptor agonist lixisenatide and with the combination of insulin glargine and lixisenatide. Each study was accompanied by one lean (Fa/?) and one obese (fa/fa) untreated non-diabetic and diabetic control group, respectively. Blood glucose, body weight alterations and food assimilation efficiency were monitored. RESULTS: In control ZDF rats, more than 12 g/day of pure glucose was urinarily excreted. In total, the energetic loss via urine exceeded 30% from total energy uptake. Insulin glargine treatment decreased urinary energetic loss, leading to a body weight gain of approximately 3 g/day. An almost body weight-neutral antihyperglycaemic treatment could be achieved with AVE2268 and lixisenatide. While lixisenatide reduced body weight gain via reduction of energy uptake, the SGLT2 inhibitor even increased urinary glucose and thus energy excretion. Combining insulin glargine with lixisenatide attenuated the anabolic effect of insulin resulting in weight neutrality. CONCLUSIONS: Our data clearly show renal contribution to the body's energy control by urinary glucose excretion (UGE) during antidiabetic treatment. The undesired retained energy could be reduced via additional UGE or via simultaneous reduction of energy uptake and/or energy retention.


Asunto(s)
Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Glucósidos/farmacología , Hipoglucemiantes/farmacología , Insulina de Acción Prolongada/farmacología , Péptidos/farmacología , Animales , Glucemia/efectos de los fármacos , Receptor del Péptido 1 Similar al Glucagón , Hemoglobina Glucada/efectos de los fármacos , Insulina Glargina , Riñón/efectos de los fármacos , Masculino , Ratas , Ratas Zucker , Receptores de Glucagón/agonistas , Transportador 2 de Sodio-Glucosa , Inhibidores del Cotransportador de Sodio-Glucosa 2 , Aumento de Peso/efectos de los fármacos
4.
Pathologe ; 34(4): 335-7, 2013 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-23436120

RESUMEN

Maxillary ameloblastomas can extensively expand into the paranasal sinuses or even the nasal cavity due to a slow growth pattern. Sinusitis is rarely the first tumor-related complaint. Due to the various growth forms of ameloblastomas the challenging histological differential diagnosis includes several other odontogenic as well as benign and malignant non-odontogenic tumors, e.g. tumors from the mucosa of the paranasal sinuses, salivary glands and Rathke's pouch. Despite the radical surgical approach a complete resection with wide margins cannot always be achieved. Maxillary ameloblastomas show the highest recurrence rates.


Asunto(s)
Ameloblastoma/patología , Senos Etmoidales/patología , Neoplasias Maxilares/patología , Neoplasias del Seno Maxilar/patología , Neoplasias Nasales/patología , Neoplasias de los Senos Paranasales/patología , Adulto , Ameloblastoma/cirugía , Endoscopía , Senos Etmoidales/cirugía , Estudios de Seguimiento , Humanos , Masculino , Maxilar/patología , Maxilar/cirugía , Neoplasias Maxilares/cirugía , Neoplasias del Seno Maxilar/cirugía , Cavidad Nasal/patología , Invasividad Neoplásica , Neoplasias Nasales/cirugía , Trastornos del Olfato/etiología , Neoplasias de los Senos Paranasales/cirugía , Radiografía Panorámica , Sinusitis/etiología , Sinusitis/cirugía , Tomografía Computarizada por Rayos X
5.
J Exp Med ; 192(6): 801-11, 2000 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-10993911

RESUMEN

Mast cells (MCs) are immunoregulatory and inflammatory tissue cells preferentially located around blood vessels. Since endothelial cells have been suggested to regulate MC functions, we analyzed MC-endothelial cell interactions in vitro by performing coculture experiments with purified human intestinal MCs and human umbilical vein endothelial cells (HUVECs). We found that HUVECs provide signals allowing MCs to survive for at least 3 wk and to proliferate without addition of cytokines; otherwise all MCs died. HUVEC-dependent MC proliferation was more pronounced than that induced by stem cell factor (SCF), known to act as an MC growth factor both in vitro and in vivo. After coculture with HUVECs, most MCs were of the tryptase and chymase double-positive phenotype (MC(TC)). Transwell experiments suggested that the HUVECs' effects on MCs are not mediated by soluble factors. HUVEC-dependent MC adhesion and proliferation were inhibited by neutralizing antibodies directed against SCF and vascular cell adhesion molecule (VCAM)-1 expressed on HUVECs, and c-kit and very late antigen 4 (VLA-4) on MCs. The data suggest that two mechanisms (membrane-bound SCF/c-kit and VCAM-1/VLA-4) are involved in human MC-endothelial cell interactions. In conclusion, our study provides evidence that endothelial cells regulate MC survival and preferentially support human MC(TC) development.


Asunto(s)
Endotelio Vascular/fisiología , Mastocitos/citología , Mastocitos/fisiología , Anticuerpos/farmacología , Antígenos CD/análisis , Apoptosis , División Celular , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Técnicas de Cocultivo , Citocinas/farmacología , Endotelio Vascular/citología , Endotelio Vascular/ultraestructura , Humanos , Integrina alfa4beta1 , Integrinas/análisis , Mucosa Intestinal/citología , Mastocitos/efectos de los fármacos , Proteínas Proto-Oncogénicas c-kit/análisis , Receptores Mensajeros de Linfocitos/análisis , Transducción de Señal , Factor de Células Madre/análisis , Factor de Células Madre/fisiología , Factores de Tiempo , Venas Umbilicales , Molécula 1 de Adhesión Celular Vascular/análisis , Molécula 1 de Adhesión Celular Vascular/fisiología
6.
J Clin Immunol ; 29(4): 545-54, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19353249

RESUMEN

PURPOSE: The major histocompatibility complex class I related A (MICA) and MICB molecules are ligands of NKG2D receptors on natural killer cells, gamma/delta T cells, and CD8ass T cells that mediate host antitumor immune response. The role of MICA-TM and MICB C1_2_A alleles in patients with colorectal cancer has not yet been investigated. METHODS: We have analyzed the MICA-TM and MICB C1_2_A polymorphisms in colorectal cancer patients (n = 79) by polymerase chain reaction amplification, subsequent electrophoresis, and sequencing in comparison to a previously analyzed cohort of healthy controls (n = 306). Allele frequencies obtained for MICA-TM and MICB C1_2_A were compared to histopathological data regarding tumor invasion, disease progression, microsatellite instability, and the presence of KRAS mutations (codon 12) and analyzed for possible impact on tumor-related survival (n = 61). RESULTS: Allele frequencies of MICA-TM and MICB C1_2_A polymorphisms were not different in patients with colorectal cancer in comparison to normal controls. In colorectal cancer patients, MICA-TM A4 allele was directly and MICA-TM A5 allele was inversely associated with lymph node involvement and advanced UICC stages. Tumor-related survival in colorectal cancer patients was significantly reduced in the presence of the MICA-TM A4 allele (p = 0.015). In patients with microsatellite stable tumors, survival was reduced in association with the MICA-TM A4 allele (p = 0.006) and MICA-TM A9 allele (p = 0.034), but increased in patients showing the MICA-TM A5 allele (p = 0.042). CONCLUSIONS: Specific MICA-TM alleles seem to influence tumor progression and midterm survival of patients with colorectal cancer, indicating an important role of host innate immune predisposition involving NKG2D mediated antitumor response.


Asunto(s)
Neoplasias Colorrectales/genética , Antígenos de Histocompatibilidad Clase I/genética , Repeticiones de Microsatélite/genética , Proteínas Proto-Oncogénicas/genética , Proteínas ras/genética , Adulto , Anciano , Anciano de 80 o más Años , Alelos , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/patología , Femenino , Frecuencia de los Genes , Genotipo , Antígenos de Histocompatibilidad Clase I/inmunología , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Mutación/genética , Polimorfismo Genético , Proteínas Proto-Oncogénicas/inmunología , Proteínas Proto-Oncogénicas p21(ras) , Proteínas ras/inmunología
7.
Eur J Clin Pharmacol ; 65(8): 783-8, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19319511

RESUMEN

PURPOSE: Anticoagulation therapy with coumarins necessitates a strict individualization of dosing. Whereas the impacts of the cytochrome P450 2C9 (CYP2C9) and vitamin K epoxide reductase (VKORC1) polymorphisms on warfarin dosing are clearly established, the role of these genetic variants on dosing and the safe use of phenprocoumon are less well investigated and, to a certain degree, controversial. METHODS: We studied the most frequent functional polymorphisms of VKORC1, CYP2C9, and CYP3A5 in 60 consecutive patients demonstrating complicated phenprocoumon-mediated anticoagulation and in 120 controls. RESULTS: The frequencies of the less active VKORC1 haplotype A-group alleles (p < 0.0001) and of CYP2C9 genotypes with two variant alleles (p = 0.035) were higher in the patient cohort than in the control group, while the frequency of patients carrying only one variant CYP2C9 allele was unchanged relative to the control subjects (RR 1.2; p = 0.49). CONCLUSION: The data suggest a fundamental role of VKORC1 haplotypes and a minor role of CYP2C9 variants in the anticoagulation property of phenprocoumon.


Asunto(s)
Anticoagulantes/administración & dosificación , Anticoagulantes/farmacocinética , Hidrocarburo de Aril Hidroxilasas/genética , Citocromo P-450 CYP3A/genética , Oxigenasas de Función Mixta/genética , Fenprocumón/administración & dosificación , Fenprocumón/farmacocinética , Polimorfismo Genético , Población Blanca/genética , Administración Oral , Anciano , Anciano de 80 o más Años , Citocromo P-450 CYP2C9 , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Frecuencia de los Genes , Genotipo , Alemania , Haplotipos , Humanos , Masculino , Persona de Mediana Edad , Vitamina K Epóxido Reductasas
9.
Int J Tuberc Lung Dis ; 22(3): 309-320, 2018 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-29471910

RESUMEN

BACKGROUND: The effect of quality improvement measures on the performance of diagnostic tuberculosis (TB) laboratories in low- and lower-middle-income countries is not known, and is the subject of this review. METHODS: Three databases were searched for quality improvement studies presenting data on performance parameters before and after the implementation of quality improvement interventions. RESULTS: Twenty-one studies were included in this review. Quality improvement measures were most frequently implemented by an external organization; settings targeted ranged from microscopy centers, hospitals, districts, regional and national reference laboratories. Quality improvement interventions and outcome measurements were highly heterogeneous. Most studies investigated interventions aimed at improving smear microscopy (n = 17). Two studies evaluated comprehensive quality improvement measures (n = 2) and another three studies focused on mycobacterial culture and drug susceptibility testing. Most studies showed an improvement in outcomes measured on before-after or time trend analysis. CONCLUSION: Quality improvement measures implemented in TB laboratories showed a positive impact on various outcomes. Due to the high heterogeneity of outcome reporting and interventions and the low quality of the studies, the effect size was not clear. Identification of standardized quality indicators and their link to the quality of patient care would improve knowledge in this field.


Asunto(s)
Evaluación de Resultado en la Atención de Salud/normas , Mejoramiento de la Calidad/normas , Tuberculosis/diagnóstico , Países en Desarrollo , Humanos , Laboratorios , Pruebas de Sensibilidad Microbiana , Mycobacterium tuberculosis/efectos de los fármacos , Ensayos Clínicos Controlados Aleatorios como Asunto
10.
Int J Clin Pharmacol Ther ; 44(9): 397-400, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16995327

RESUMEN

OBJECTIVE: We reported recently that celecoxib inhibits the metabolism of the cytochrome P450 (CYP)2D6 substrate metoprolol in volunteers. Valdecoxib, the active metabolite of parecoxib, has also been claimed to interfere with the metabolism of CYP2D6 substrates. However, little support for this contention is available despite the intensive use of parecoxib in the perioperative setting. Therefore, the objective of this study was to examine the effect of valdecoxib on the pharmacokinetics of the clinically relevant CYP2D6 substrate metoprolol. METHODS: An open, randomized, 3-period crossover study was performed in 15 healthy male volunteers. Metoprolol (50 mg) was given in all 3 periods without, or following a 7-day pre-treatment with valdecoxib (20 mg, o.d.) or rofecoxib (25 mg, o.d.), to achieve steady state conditions of COX-2 inhibitors in Periods 2 and 3. In a small group of extensive metabolizers (EM/EM), short-term application of twice the dose was investigated. RESULTS: No effect of valdecoxib (20 mg/d) or rofecoxib (25 mg/d) were detected on the area under the plasma concentration-time curve of metoprolol (323 +/- 333 to 324 +/- 296 or 309 +/- 256 microg x h/l) or at a higher dose. No significant changes of pharmacokinetic or pharmacodynamic parameters of metoprolol were apparent. CONCLUSION: We conclude that, at therapeutic doses, valdecoxib and rofecoxib do not influence the CYP2D6 substrate metoprolol.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Inhibidores de la Ciclooxigenasa 2/farmacología , Citocromo P-450 CYP2D6/metabolismo , Isoxazoles/farmacología , Metoprolol/farmacocinética , Sulfonamidas/farmacología , Adulto , Estudios Cruzados , Citocromo P-450 CYP2D6/genética , Humanos , Lactonas/farmacología , Masculino , Metoprolol/sangre , Profármacos/farmacología , Sulfonas/farmacología
11.
Artículo en Inglés | MEDLINE | ID: mdl-27354779

RESUMEN

Osteoporosis is more common in patients with COPD and in smokers. The aim of this study was to assess whether measures of emphysema and airway disease on computed tomography (CT) were associated with lower bone density or vertebral fractures in smokers with and without COPD. For this purpose, we included participants from the NELSON lung cancer screening trial. Bone density was measured as Hounsfield Units in the first lumbar vertebra, and vertebral fractures were assessed semiquantitatively. The 15th percentile method (Perc15) was used to assess emphysema, and the airway lumen perimeter (Pi10) was used for airway wall thickness. Expiratory/inspiratory-ratiomean lung density (E/I-ratioMLD) was used as a measure for air trapping and tracheal index to assess tracheal deformity. Linear regression models and logistic regression models were used to assess associations between CT biomarkers, bone density, and presence of fractures. Exactly 1,093 male participants were eligible for analysis. Lower Perc15 and higher E/I-ratioMLD were significantly associated with lower bone density (b=-1.27, P=0.02 and b=-0.37, P=0.02, respectively). Pi10 and tracheal index were not associated with bone density changes. CT-derived biomarkers were not associated with fracture prevalence. Bone density is lower with increasing extent of emphysema and small airway disease but is not associated with large airway disease and tracheal deformity. This may indicate the necessity to measure bone density early in smokers with emphysema and air trapping to prevent vertebral fractures.


Asunto(s)
Densidad Ósea , Vértebras Lumbares/diagnóstico por imagen , Osteoporosis/diagnóstico por imagen , Fracturas Osteoporóticas/diagnóstico por imagen , Enfermedad Pulmonar Obstructiva Crónica/etiología , Enfisema Pulmonar/etiología , Fumar/efectos adversos , Fracturas de la Columna Vertebral/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Anciano , Bélgica , Progresión de la Enfermedad , Humanos , Modelos Lineales , Modelos Logísticos , Vértebras Lumbares/lesiones , Vértebras Lumbares/fisiopatología , Pulmón/fisiopatología , Masculino , Persona de Mediana Edad , Países Bajos , Oportunidad Relativa , Osteoporosis/etiología , Osteoporosis/fisiopatología , Fracturas Osteoporóticas/etiología , Fracturas Osteoporóticas/fisiopatología , Valor Predictivo de las Pruebas , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Enfisema Pulmonar/diagnóstico , Enfisema Pulmonar/fisiopatología , Factores de Riesgo , Índice de Severidad de la Enfermedad , Fracturas de la Columna Vertebral/etiología , Fracturas de la Columna Vertebral/fisiopatología
12.
J Med Chem ; 33(11): 2976-81, 1990 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1977910

RESUMEN

In the course of studies on tranquilizers, new non-benzodiazepine-like compounds were synthesized. These are 1-(3,4,5-trimethoxyphenoxy)-3-[4-(2-methoxyphenyl)piperazinyl]prop an-2-ol (INN: enciprazine) and derivatives thereof which were screened pharmacologically in order to evaluate their central nervous system activity. Compounds with marked antiaggressive and anxiolytic properties but without dependence potential could be detected. Enciprazine was selected for clinical investigations.


Asunto(s)
Ansiolíticos/síntesis química , Piperazinas/síntesis química , Agresión/efectos de los fármacos , Animales , Ansiolíticos/química , Ansiolíticos/farmacología , Ansiolíticos/toxicidad , Conducta Animal/efectos de los fármacos , Fenómenos Químicos , Química , Conducta Exploratoria/efectos de los fármacos , Femenino , Masculino , Ratones , Estructura Molecular , Piperazinas/química , Piperazinas/farmacología , Piperazinas/toxicidad , Ratas , Autoadministración , Relación Estructura-Actividad , Trastornos Relacionados con Sustancias
13.
Br J Pharmacol ; 39(2): 390-7, 1970 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-4393215

RESUMEN

1. The interaction of angiotensin and several inhibitors of the uptake of noradrenaline across the neuronal membrane (cocaine, desipramine, protriptyline. and pronethalol) on the output of noradrenaline produced by sympathetic nerve stimulation has been studied in the isolated perfused rabbit heart.2. Most of these drugs increased noradrenaline outflow-angiotensin, for example, by 175%. Cocaine (10(-4)M) did not change the amine overflow, probably because this very high concentration inhibited not only the re-uptake but also the liberation of noradrenaline.3. Desipramine, protriptyline, and pronethalol, although infused in concentrations which enhanced the noradrenaline output, were not able to impair the angiotensin-induced increase of transmitter overflow. In the presence of cocaine (10(-4)M) the increase elicited by angiotensin was slightly reduced, though lower concentrations of cocaine, as previously described, do not interfere with the effect of angiotensin.4. In contrast to the interaction between uptake inhibitors and angiotensin, the augmented output of noradrenaline caused by an uptake inhibitor could not be increased further by infusion of a second uptake inhibitor.5. It is concluded that the increase of the outflow of noradrenaline during sympathetic nerve stimulation by small doses of angiotensin is not caused by an inhibition of re-uptake. On the contrary, the transmitter liberation seems to be facilitated. This is a novel principle of drug action on the sympathetic nerve terminals.


Asunto(s)
Angiotensina II/farmacología , Corazón/inervación , Norepinefrina/metabolismo , Sistema Nervioso Simpático/efectos de los fármacos , Animales , Cocaína/farmacología , Desipramina/farmacología , Dibenzocicloheptenos/farmacología , Estimulación Eléctrica , Etanolaminas/farmacología , Corazón/efectos de los fármacos , Técnicas In Vitro , Conejos , Sistema Nervioso Simpático/metabolismo
14.
Br J Pharmacol ; 105(3): 732-8, 1992 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1628159

RESUMEN

1. The purpose of the present study was to relate the effects of the novel drug, anpirtoline, on 5-hydroxytryptamine (5-HT) receptor subtypes to its antinociceptive and antidepressant-like actions in rodents. 2. Binding assays with rat brain membranes have shown that anpirtoline bound with a much higher affinity to 5-HT1B receptor (Ki = 28 nM) than to 5-HT1A (Ki = 150 nM) and 5-HT2 (Ki = 1.49 microM) receptors. 3. Like 5-HT, anpirtoline concentration-dependently inhibited forskolin-stimulated adenylate cyclase activity in homogenates from the rat substantia nigra. Both effects were not additive, and could be prevented by 5-HT1B receptor antagonists such as propranolol and penbutolol. 4. In superfused rat and pig brain cortex slices preincubated with [3H]-5-HT, the electrically evoked tritium overflow was inhibited by anpirtoline and 5-HT. Whereas 5-HT was equipotent in both tissues (EC50 = 69 nM), anpirtoline was markedly less potent in pig brain cortex slices (EC50 = 1190 nM) than in rat brain cortex slices (EC50 = 55 nM). The concentration-response curve for anpirtoline was shifted to the right by metitepine in both preparations. 5. In the social behaviour deficit test, anpirtoline and trifluoromethylphenyl-piperazine were effective in reversing the isolation-induced impairments in mice, an effect shown only by compounds with agonist properties at the 5-HT1B receptor. 6. In the electrostimulated pain test using mice, anpirtoline dose-dependently increased the pain threshold with an ED50 of 0.52 mg kg-1, i.p. The antinociceptive activity of anpirtoline was abolished by pretreatment with cyproheptadine or propranolol.7. In the forced swimming test in rats, anpirtoline induced a dose-related increase in swimming activity. With an ED50 value of 4.6mgkg-1, i.p., anpirtoline was 4 times more potent than the two standard compounds imipramine and desipramine. The decrease of immobility time or the increase of active periods in this model of behavioural despair is suggested to be characteristic of antidepressant drugs.8. Anpirtoline exhibits both antinociceptive and antidepressant-like activities in animals. It is probable that anpirtoline elicits these pharmacological effects via its agonist effect on 5-HT1B and 5-HT1A receptors.


Asunto(s)
Analgésicos/farmacología , Antidepresivos/farmacología , Piperidinas/farmacología , Piridinas/farmacología , Receptores de Serotonina/fisiología , Inhibidores de Adenilato Ciclasa , Animales , Química Encefálica/efectos de los fármacos , Estimulación Eléctrica , Femenino , Técnicas In Vitro , Masculino , Ratones , Ratas , Ratas Endogámicas , Receptores de Serotonina/efectos de los fármacos , Conducta Social , Aislamiento Social , Porcinos
15.
J Control Release ; 53(1-3): 195-203, 1998 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-9741927

RESUMEN

We investigated the transport- and metabolism properties of three peptides in monolayers of human nasal epithelial cells. The effective permeability coefficients of thyrotropin-releasing hormone, met-enkephalin and human recombinant insulin were found to be 4.5, 4.4 and 0.4 x 10(-7) cm/s, respectively. The permeability was inversely proportional to the molecular weight and one order of magnitude lower than in excised nasal mucosa of rabbits. The metabolic cleavage of thyrotropin-releasing hormone (TRH) to the free acid by cytosolic prolyl-endopeptidase was also detected in human nasal cell monolayers, suggesting that ca. 10% of the total amount of TRH is transported via a transcellular pathway. Met-enkephalin is a substrate for aminopeptidases, located on the apical membrane of nasal epithelial cells. Metabolites and enzyme activity are comparable with literature data. Our studies demonstrate that not only morphological, but also functional properties of human nasal epithelial cells are preserved under in vitro conditions. Such a cell culture model based on human nasal cells could be beneficial for the characterization of peptide transport on a cellular level and for investigation of the absorption enhancer mechanism. Further studies are necessary, however, to establish correlations between in vitro permeabilities in cell cultures and nasal drug absorption in animals and humans.


Asunto(s)
Encefalina Metionina/administración & dosificación , Insulina/administración & dosificación , Mucosa Olfatoria/metabolismo , Hormona Liberadora de Tirotropina/administración & dosificación , Administración Intranasal , Secuencia de Aminoácidos , Animales , Transporte Biológico , Células Cultivadas , Encefalina Metionina/metabolismo , Encefalina Metionina/farmacocinética , Humanos , Técnicas In Vitro , Insulina/metabolismo , Insulina/farmacocinética , Conejos , Hormona Liberadora de Tirotropina/metabolismo , Hormona Liberadora de Tirotropina/farmacocinética
16.
Naunyn Schmiedebergs Arch Pharmacol ; 362(2): 110-5, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10961372

RESUMEN

Improvement of non-surgical strategies is a pivotal task in the treatment of pancreatic cancer. Response to treatment with most anticancer agents has been very poor, probably due to insufficient drug concentration in tumor tissue. Increased response rates during chemotherapy might be achieved by dose escalation; however, this approach is often hampered by severe side effects. One strategy to overcome these adverse effects is application of nontoxic glucuronide prodrugs from which the active moiety is released by beta-glucuronidase within or near the tumor. The use of glucuronide prodrugs in pancreatic cancer requires increased expression of the enzyme in the diseased tissue, a problem that has not been addressed so far. We therefore investigated function and expression of beta-glucuronidase in tissue samples from human healthy pancreas (n=7) and pancreatic adenocarcinoma (n=8), respectively. Comparing the ability of tissue homogenates to cleave the standard substrate 4-methylumbelliferyl-beta-D-glucuronide, we found a significantly increased specific beta-glucuronidase activity (P<0.05) in pancreatic cancer (median: 133; 75% percentile: 286; 25% percentile: 111 nmol/mg per h) as compared to healthy pancreas (median: 74; 75% percentile: 113; 25% percentile: 71 nmol/mg per h). Enzyme kinetic experiments with the model prodrug N-[4-beta-glucuronyl-3-nitrobenzyloxycarbonyl] doxorubicin (HMR 1826) demonstrated bioactivation of HMR 1826 by pancreatic beta-glucuronidase. Enzymatic activity was found to be closely related to enzyme contents (r=0.87) as assessed by Western blot analysis. Our data indicate that increased beta-glucuronidase activity in pancreatic cancer seems to be due to an elevated steady-state level of the protein. This may be the basis for new therapeutic strategies in treatment of pancreatic carcinoma by using glucuronide prodrugs of anticancer agents.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/enzimología , Antineoplásicos/farmacología , Glucuronidasa/biosíntesis , Glucuronidasa/metabolismo , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/enzimología , Adenocarcinoma/patología , Adolescente , Adulto , Antibióticos Antineoplásicos/farmacología , Western Blotting , Cromatografía Líquida de Alta Presión , Densitometría , Doxorrubicina/análogos & derivados , Doxorrubicina/farmacología , Femenino , Glucuronatos/farmacología , Humanos , Cinética , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/patología , Pancreatitis/enzimología , Pancreatitis/patología , Profármacos
17.
Eur J Surg Oncol ; 27(3): 286-90, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11373107

RESUMEN

AIMS: The prognosis of patients with peritoneal carcinomatosis from gastrointestinal malignancies is poor. The aim of this study was to analyse the results of multimodality treatment for peritoneal carcinomatosis of appendiceal carcinoma. PATIENTS AND METHODS: From 07/95 to 01/00, 17 patients (13 males, 4 female, median age 58 years) underwent peritonectomy procedures in combination with intraperitoneal hyperthermic chemotherapy. Surgical, pathological and survival data were analysed retrospectively. RESULTS: All patients had undergone previous surgical treatment and one patient had received chemotherapy. In all patients peritonectomy procedures, as described by Sugarbaker, were performed with the aim of achieving a macroscopically complete cytoreduction (range 2-6, median 4 procedures per patient). Following resection, open hyperthermic intraperitoneal chemotherapy with cisplatin was performed. Eleven patients had postoperative complications (predominantly "non-surgical") and two patients died postoperatively. The 4-year survival rate was 75%. Complete cytoreducion had a statistically significant positive influence on long-term survival. CONCLUSIONS: In selected patients (WHO status 0/1, minimal residual disease, no distant metastases, complete cytoreduction), the prognosis for patients with peritoneal carcinomatosis of appendiceal origin can be improved by peritonectomy procedures and hyperthermic intraperitoneal chemotherapy. Postoperative morbidity may be increased due to "non-surgical" complications.


Asunto(s)
Neoplasias del Apéndice/patología , Carcinoma/secundario , Carcinoma/terapia , Cisplatino/administración & dosificación , Neoplasias Peritoneales/secundario , Neoplasias Peritoneales/terapia , Adulto , Anciano , Antineoplásicos/uso terapéutico , Neoplasias del Apéndice/terapia , Carcinoma/mortalidad , Femenino , Humanos , Hipertermia Inducida , Inyecciones Intraperitoneales , Masculino , Persona de Mediana Edad , Neoplasias Peritoneales/mortalidad , Peritoneo/cirugía , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia , Resultado del Tratamiento
18.
Anticancer Res ; 20(6D): 4953-5, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11326645

RESUMEN

BACKGROUND: During recent years a discussion about cost-effectiveness and importance of follow-up determination of carcinoembryonic antigen (CEA) after curative resection of large bowel cancer has developed. PATIENTS AND METHODS: Between 1990 and 1998 follow-up CEA levels of 1,321 patients after curative colorectal cancer resection were prospectively collected in cooperation with family physicians, CEA determinations were made with different assays by various laboratories. The reported findings were adjusted for the different methods used. RESULTS: 306 patients developed recurrent disease following curative cancer resection (23.2% of all patients). Regarding the role of follow-up CEA determination, they were divided into: I. no preoperative CEA determination/insufficient follow-up (N = 47); II. no elevation of CEA with primary cancer, a) elevation with recurrent disease (N = 62), b) no elevation at any time point (N = 53), c) role of CEA not completely elucidated (N = 41); III. elevated CEA levels with primary cancer, a) no increase with recurrent disease (N = 21), b) increase with other symptoms of recurrent disease (N = 45), c) increased levels as early symptom of recurrent disease (N = 37). 30 patients (9.8% of all patients with recurrent disease; 2.3% of all patients) with increased CEA levels at the time of recurrent disease underwent surgical resection with curative intention (R0 resection). CONCLUSIONS: Our findings indicate that up to 47% of the patients with recurrent disease and 11% of all patients (N = 144, groups IIa + IIIb + IIIc) could benefit from routine follow-up CEA determinations after curative colorectal cancer resection. Nonetheless, only 2.3% of all patients with elevated CEA levels underwent R0 resection of recurrent disease. Despite these detection and R0 resectability rates, CEA plays a crucial role in the early detection of recurrent disease and remains an important part of routine patient care after curative resection of colorectal cancer.


Asunto(s)
Biomarcadores de Tumor/análisis , Antígeno Carcinoembrionario/análisis , Neoplasias Colorrectales/diagnóstico , Recurrencia Local de Neoplasia/diagnóstico , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/cirugía , Estudios de Seguimiento , Humanos , Incidencia , Recurrencia Local de Neoplasia/epidemiología , Recurrencia Local de Neoplasia/metabolismo , Pronóstico
19.
Anticancer Res ; 20(6D): 5195-8, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11326694

RESUMEN

UNLABELLED: Carcinoembrionic Antigen (CEA) and carbohydrate antigen 19-9 (CA 19-9) are the most commonly used tumor-associated antigens in the management of patients with colorectal cancer. The aim of this study was to evaluate the prognostic value of preoperative serum levels of CEA and/or CA 19-9 and the classical prognostic factors (age, sex, tumor infiltration and staging) in 495 patients. PATIENTS AND METHODS: The retrospective study was performed on frozen sera (stored at -70 degrees C) of patients with histologically proven colorectal cancer. Survival function estimates were calculated (Kaplan-Meier). The patients were separated into two groups according to the preoperative marker levels. Cut-off levels calculated at a specificity of 100% versus healthy individuals were used: < 4 ng/mL versus > or = 4 ng/mL for CEA and < 60 U/mL versus > or = 60 U/mL for CA 19-9. Survival curve differences were assessed using the log-rank-test. Mulivariate Cox's proportional hazard regression analysis was performed to examine the association between tumor marker levels and survival time. Classical prognostic factors such as age, sex, tumor infiltration, tumor stage (Dukes' classification) were included as covariants. The mantel-Haenszel method was used to assess the survival rate of patients with colorectal carcinoma and high versus low levels of tumor-associated antigens according to tumor stages. RESULTS: The Dukes' stages (log-rank chi-square = 231.9; p < 0.0001) represent the best prognostic factor besides the preoperative values of CA 19-9 (log-rank chi-square = 162.5). CEA shows a log-rank chi-square of 71.4. Thus, CEA and CA 19-9 can be used to discriminate two groups of patients with significantly different survival times (p < 0.0001). The importance of different parameters in providing additional prognostic information was evaluated by multivariate analysis. Only items of statistically significant prognostic relevance (univariate analysis) were used for this analysis. Estimated relative risks of death adjusted for tumor stage were 5.5 considering Dukes' stage A versus Dukes' stage B/C and Dukes' stage B/C versus Dukes' stage D, respectively, and an increasing relative risk of 27.5 for Dukes' stage A versus Dukes' stage D (p < 0.001). The relative risk for preoperative CA 19-9 serum concentrations (> or = 60 U/mL versus < 60 U/mL) was 2.3 (p < 0.001) and for preoperative CEA concentrations (> or = 4 ng/mL versus < 4 ng/mL) 1.4 (p < 0.07). For CEA the 2-year survival rates in the group of patients with preoperative serum concentrations > 4 ng/mL versus < 4 ng/mL and Dukes' stage D were 16% versus 38%, in Dukes' stage B/C 73% versus 91% and in Dukes' stage A 100% versus 98%. For CA 19-9 the 2-year survival rates in the group of patients with preoperative serum concentrations > or = 60 U/mL versus < 60 U/mL and Dukes' stage D were 10% versus 39%, whilst in Dukes' stage B/C 58% versus 87%. In the group of patients with Dukes' stage A with serum levels > or = 60 U/mL a 2-years survival rate of 100% was found. CONCLUSION: The postoperative Dukes' classification represents the best prognostic information besides the preoperative values of CA 19-9. The predictive information provided by preoperative CA 19-9 serum levels is independent from that obtained by the other factors investigated. Only Dukes' classification and CA 19-9 levels showed statistical significance (p < 0.001).


Asunto(s)
Biomarcadores de Tumor/sangre , Antígeno CA-19-9/sangre , Antígeno Carcinoembrionario/sangre , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/sangre , Neoplasias Colorrectales/mortalidad , Femenino , Humanos , Masculino , Análisis Multivariante , Pronóstico , Estudios Retrospectivos , Análisis de Supervivencia
20.
Anticancer Res ; 17(4B): 2935-8, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9329568

RESUMEN

UNLABELLED: The prognostic information provided by preoperative serum CEA, CA 19-9 antigen assays as compared with the classical prognostic factors (age, sex, tumor infiltration, tumor stage (Dukes') and R-classification) in 495 patients with colorectal carcinoma was analysed. PATIENTS AND METHODS: Survival function estimates were calculated according to Kaplan-Meier. The patients were separated into two groups according to the preoperative marker levels. Fixing specificity at 100% for healthy people, cut off levels were calculated. Survival curve differences were assessed using the log-rank-test. Multivariate Cox's proportional hazard regression analysis was performed. The Mantel-Haenszel method was used to assess the survival rate of patients with colorectal carcinoma and high versus low levels of tumor-associated antigens according to tumor stages. The study was performed on the frozen sera (stored at -80 degrees C) of 495 patients with histologically proven colorectal carcinoma. RESULTS: The Dukes' stages (log-rank chi-square = 231.9; P < 0.0001) represent the best prognostic factor besides the preoperative values of CA 19-9 (log-rank chi-square = 162.5). CEA shows a log-rank chi-square of 71.4. Thus, CEA and CA 19-9 can be used to discriminate two groups of patients with significantly different survival times (P < 0.0001). The importance of different parameters in providing additional prognostic information was evaluated by multivariate analysis (Cox's model). Estimated relative risks of death adjusted for tumor stage were 5.5 for Dukes' stage A versus Dukes' stage B/C and Dukes' stage B/C versus Dukes' stage D, respectively and an increasing relative risk of 27.5 for Dukes' stage A versus Dukes' stage D (P < 0.001). The relative risk for preoperative CA 19-9 serum concentrations (> or = 60 U/mL versus < 60 U/mL) was 2.3 (P < 0.001) for preoperative CEA concentrations (> or = 4 ng/mL versus < 4 ng/mL) 1.4 (P < 0.07). For CEA the 2-years survival rates in the group of patients with preoperative serum concentrations > or = 4 ng/mL versus < 4 ng/mL and Dukes' stage D were 16% versus 38%, in Dukes' stage B/C 73% versus 91% and in Dukes' stage A 100% versus 98%. For CA 19-9 the 2-years survival rates in the group of patients with preoperative serum concentrations > or = 60 U/mL versus < 60 U/mL and Dukes' stage D were 10% versus 39%, in Dukes' stage B/C 58% versus 87%. In the group of patients with Dukes' stage A with serum levels > or = 60 U/mL a 2-year survival rate of 100% was found. In the corresponding group only one patient exists. CONCLUSION: The postoperative Dukes' classification provides the best prognostic information besides the preoperative values of CA 19-9. The predictive information provided by the preoperative CA 19-9 serum level is additional to that obtained from the other factors investigated.


Asunto(s)
Antígeno CA-19-9/sangre , Antígeno Carcinoembrionario/sangre , Neoplasias Colorrectales/sangre , Neoplasias Colorrectales/mortalidad , Humanos , Análisis Multivariante , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia
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