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1.
Br J Haematol ; 202(6): 1137-1150, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37460273

RESUMEN

Adaptor chimeric antigen receptor (CAR) T-cell therapy offers solutions for improved safety and antigen escape, which represent main obstacles for the clinical translation of CAR T-cell therapy in myeloid malignancies. The adaptor CAR T-cell platform 'UniCAR' is currently under early clinical investigation. Recently, the first proof of concept of a well-tolerated, rapidly switchable, CD123-directed UniCAR T-cell product treating patients with acute myeloid leukaemia (AML) was reported. Relapsed and refractory AML is prone to high plasticity under therapy pressure targeting one single tumour antigen. Thus, targeting of multiple tumour antigens seems to be required to achieve durable anti-tumour responses, underlining the need to further design alternative AML-specific target modules (TM) for the UniCAR platform. We here present the preclinical development of a novel FMS-like tyrosine kinase 3 (FLT3)-directed UniCAR T-cell therapy, which is highly effective for in vitro killing of both AML cell lines and primary AML samples. Furthermore, we show in vivo functionality in a murine xenograft model. PET analyses further demonstrate a short serum half-life of FLT3 TMs, which will enable a rapid on/off switch of UniCAR T cells. Overall, the presented preclinical data encourage the further development and clinical translation of FLT3-specific UniCAR T cells for the therapy of AML.


Asunto(s)
Leucemia Mieloide Aguda , Tirosina Quinasa 3 Similar a fms , Humanos , Animales , Ratones , Tirosina Quinasa 3 Similar a fms/genética , Tirosina Quinasa 3 Similar a fms/metabolismo , Inmunoterapia Adoptiva , Linfocitos T , Antígenos de Neoplasias , Leucemia Mieloide Aguda/tratamiento farmacológico
2.
Gesundheitswesen ; 78(11): 695-707, 2016 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-26335658

RESUMEN

Aim: 20 years after establishment of the National Breastfeeding Committee, the present work, based on published data on breastfeeding, is aimed at providing insight into the development of breastfeeding behaviour in Germany. Methods: To identify relevant publications, a comprehensive literature search was conducted in PubMed and Web of Science using the search terms "breast feeding" or "breastfeeding" in combination with "Germany". The publication period was limited to the period 1995-2014. Results: A total of 35 studies with data on breastfeeding for the birth cohorts of 1990-2012 were identified. Most of the data had been collected in regional or local surveys, often retrospectively. About 60% of the studies had been conducted with the primary aim of collecting data on breastfeeding or infant nutrition. Over the past 2 decades, breastfeeding rates were always relatively high at the beginning (72-97%). However, they declined significantly within the first 2 months, and by the age of 6 months, only about 50% of infants were still breastfed. Conclusion: Breastfeeding support and early assistance should be offered to a greater extent in order to achieve sustainable improvement of breastfeeding frequency and duration in Germany. Regarding the quality of data collected on breastfeeding, it seems crucial to implement standardised approaches to monitor breastfeeding in Germany.


Asunto(s)
Lactancia Materna/estadística & datos numéricos , Lactancia Materna/tendencias , Conducta Materna , Adolescente , Adulto , Distribución por Edad , Femenino , Alemania/epidemiología , Humanos , Recién Nacido , Persona de Mediana Edad , Adulto Joven
3.
Z Rheumatol ; 73(4): 323-8, 2014 May.
Artículo en Alemán | MEDLINE | ID: mdl-24728601

RESUMEN

BACKGROUND: [corrected] There are many drugs which can cause osteoporosis or at least favor its initiation. The effect of hormones and drugs with antihormonal activity, such as glucocorticoids and aromatase inhibitors, on initiation of osteoporosis is well known. In addition, proton pump inhibitors, glitazones and diuretics also influence the formation of osteoporosis. MATERIAL AND METHODS: The results of currently available studies on the correlation between proton pump inhibitors, glitazones and diuretics on formation of osteoporosis were evaluated and summarized. RESULTS: Proton pump inhibitors and glitazones increase the risk for osteoporotic fractures. Loop diuretics may slightly increase fracture risk, whereas thiazides were shown to be osteoprotective by reducing fracture probability on a relevant scale. CONCLUSION: Proton pump inhibitors should not be prescribed without serious consideration and then only as long as necessary. Alternatively, the administration of the less effective H2 antagonists should be considered when possible due to the reduction of acid secretion. Because the long-term intake of thiazides is associated with a clinically relevant reduction in the risk of fractures and they are economic and well-tolerated, prescription can be thoroughly recommended within the framework of differential diagnostic considerations in an appropriate clinical context. The briefly increased risk of falling immediately after starting diuretic therapy is the only point which needs to be considered.


Asunto(s)
Cortisona/efectos adversos , Diuréticos/efectos adversos , Osteoporosis/inducido químicamente , Inhibidores de la Bomba de Protones/efectos adversos , Cortisona/uso terapéutico , Diuréticos/uso terapéutico , Sustitución de Medicamentos , Humanos , Cuidados a Largo Plazo , Osteoporosis/diagnóstico , Inhibidores de la Bomba de Protones/uso terapéutico , Factores de Riesgo , Estadística como Asunto , Tiazolidinedionas/efectos adversos , Tiazolidinedionas/uso terapéutico
4.
Poult Sci ; 90(10): 2169-73, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21933997

RESUMEN

The breeding of male layer chickens is currently considered to be highly uneconomical. In Germany alone, 40 to 50 million newly hatched male chickens were killed annually immediately after hatching. Therefore, it is necessary to find a method for sexing chickens early in the embryonic development, preferably before incubation. The genotypic sex of an egg can be determined using information found in the germinal disc, so knowledge of the exact position of the germinal disc is essential for further sexing, or for other actions such as the in ovo injection of agents. Previous studies have shown that the germinal disc is located somewhere on top of the yolk. However, no studies have yet been performed that investigate the influence of time spent in horizontal storage on the position of the germinal disc. Magnetic resonance imaging was chosen to determine this influence on the position of the germinal disc. It was found that eggs placed horizontally for long periods of time before scanning had significant changes in the positions of their germinal discs compared with those of eggs scanned minutes after positioning. The position of the germinal disc in eggs, minutes after horizontal positioning, deviated 14.7 ± 0.6 mm from the maximum vertical plane of the egg (zero position) in the z-direction; eggs scanned after 96 h of horizontal positioning showed a deviation of only 4.9 ± 1.6 mm. The x-axis also exhibited changes in the position of the germinal disc over time. Immediately after horizontal positioning, the eggs showed a deviation of 0.4 ± 0.4 mm in the x-direction, whereas the deviation after 96 h was 2.9 ± 0.5 mm. These results show that horizontal positioning of the egg hours before the measurement is necessary.


Asunto(s)
Blastodisco/anatomía & histología , Embrión de Pollo/anatomía & histología , Animales , Blastodisco/química , Cruzamiento , Femenino , Imagen por Resonancia Magnética , Masculino , Análisis para Determinación del Sexo/métodos , Análisis para Determinación del Sexo/veterinaria , Factores de Tiempo
5.
Gesundheitswesen ; 71(11): 709-21, 2009 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-19750459

RESUMEN

In June 1909, The Empress Auguste Victoria House in Berlin was opened. This first institute for preventive paediatrics had the objective to overcome infant mortality in Germany. This objective was attained. Since then, an unprecedented decrease of mortality in all age groups occurred as well as a doubling of life expectancy. With this "retreat of death", our concepts of health changed fundamentally, and a new spectrum of diseases emerged. This article discusses some mile stones of this change, and explains why we find more illness despite the great improvement in the field of health. The "new diseases" amenable to early prevention are presented in a table. To make disease prevention successful requires the participation of the individual. Therefore, it is important to know the demand to make a good programme effective in the population. Empirical results of a nationwide representative study on the demand by expecting and young parents for preventive consultation are presented. Anticipatory guidance of young parents is a modern approach to health promotion and disease prevention. A controlled trial shows that this approach improved knowledge, behaviour, health risk indicators, health, and development during the first two years after delivery. Future studies should focus on long term effects of early health promotion.


Asunto(s)
Promoción de la Salud/historia , Servicios Preventivos de Salud/historia , Medicina Preventiva/historia , Alemania , Historia del Siglo XX , Historia del Siglo XXI
6.
Gesundheitswesen ; 71(6): 332-8, 2009 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-19530058

RESUMEN

AIMS: The aim of this study was to collect information on and to evaluate the impact of the timing of first suckling and breast-feeding initiation in Berlin and to assess the practicability and acceptance of using a short questionnaire to collect breast-feeding data in hospitals and birth centres. METHODS: A three-month observational study was conducted in 19 maternity units and 4 birth centres, using a short questionnaire to collect quantitative data on the timing of first suckling and breast-feeding from mother-child pairs on the day of discharge. RESULTS: The data indicate a breast-feeding rate of 96.1% at discharge. Infants born in birth centres were more frequently put to their mother's breast within the first hour after birth (p<0.05), and were more frequently mainly (p<0.05) or exclusively (p<0.01) breast-fed at discharge than infants born in hospitals. Hospitals' breast-feeding policies (i.e., following the 'ten steps to successful breast-feeding') were not associated with a higher prevalence of early first suckling and any breast-feeding at discharge, but rather with exclusivity of breastfeeding (p<0.001). CONCLUSIONS: Breast-feeding initiation rates are satisfactorily high in Berlin. Rates of early first suckling and (exclusive) initial breast-feeding are highest in birth centres. No consistent association was found between hospitals' breast-feeding policy and initial breast-feeding variables. The questionnaire was well accepted and is deemed suitable for monitoring purposes.


Asunto(s)
Centros de Asistencia al Embarazo y al Parto/estadística & datos numéricos , Lactancia Materna/epidemiología , Lactancia Materna/estadística & datos numéricos , Encuestas Epidemiológicas , Maternidades/estadística & datos numéricos , Adulto , Femenino , Alemania/epidemiología , Humanos , Prevalencia , Adulto Joven
7.
Bioconjug Chem ; 19(8): 1596-603, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18651757

RESUMEN

The interest in using small peptides for therapeutic and diagnostic in vivo applications is based on several advantageous features such as good penetration into tissues and rapid clearance from the body. Because of their size, they can easily be synthesized chemically. The recently discovered cell-penetrating peptides (CPP) and among them CPP derived from the native peptide hormone human calcitonin (hCT) could meet these requirements. Therefore, they are nowadays widely used as delivery vectors for a variety of bioactive molecules. However, the knowledge about the distribution and metabolism of CPP in vivo is very limited. Hence, evaluation of the pharmacological features of any promising peptide is a crucial challenge in its development process. Herein, we studied the in vivo radiopharmacology of (68)Ga radiolabeled DOTA-modified, hCT-derived CPP in rats using small animal PET. Furthermore, the arterial blood at different time points and urine were analyzed for radio-metabolites. It was shown that d-amino acid modifications of the sequence hCT(9-32) resulted in an increased in vivo stability and lower retention in the kidney cortex of this peptide.


Asunto(s)
Calcitonina/metabolismo , Calcitonina/farmacocinética , Péptidos/metabolismo , Péptidos/farmacocinética , Secuencia de Aminoácidos , Animales , Calcitonina/química , Permeabilidad de la Membrana Celular , Quelantes/metabolismo , Radioisótopos de Galio , Compuestos Heterocíclicos con 1 Anillo/metabolismo , Humanos , Masculino , Datos de Secuencia Molecular , Péptidos/síntesis química , Péptidos/química , Fenilalanina , Tomografía de Emisión de Positrones , Ratas , Ratas Wistar , Distribución Tisular
8.
Nuklearmedizin ; 46(5): 181-4, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17938751

RESUMEN

AIM: The preparation and stability of a new (188)Re-S(4)-complex [S(4) = (1-aza-18-crown-6)(O)C-C(SH)-C(SH)-C(O)NH-(CH(2))(3)-NH-(CH(2))(3)-NHC(O)-C(SH)-C(SH)-C(O)(1-aza-18-crown-6] was studied at therapeutic relevant radioactive concentrations. The results were compared with (188)Re-MAG(3) (MAG(3): mercaptoacetyltriglycine) and (188)Re-DMSA preparations (DMSA: dimercaptosuccinic acid) performed with the same highly concentrated [(188)Re]perrhenate solution (12-15 GBq/ml). METHODS: The (188)Re complexes were prepared by direct reduction of perrhenate ((188)Re-S(4)-complex) as well as via the (188)Re-EDTA precursor complex ((188)Re-MAG(3), (188)Re-DMSA). The preparations were stabilised with 15 mg of ascorbic acid and analysed after 1, 2, and 24 hours by TLC and HPLC. Additionally, in vitro and in vivo stability studies were performed with the purified complexes. RESULTS: After stabilisation with 15 mg of ascorbic acid, all of the complexes were nearly stable under nitrogen for hours, and only 2-8% of perrhenate was observed after 24 h. In contrast, only the (188)Re-S(4) complex was completely stable in vitro and in all investigated in vivo samples after separation of ligand excess and reducing agent by HPLC. CONCLUSION: The bridging amine group or free carboxylic groups of the S(4)-ligand framework make available reactive positions for coupling biomolecules to the chelate. Thus it appears that the new (188)Re-S(4) complexes offer the possibility of stable and high specific activity labelling of biomolecules for therapeutic application.


Asunto(s)
Marcaje Isotópico/métodos , Radioisótopos , Renio , Estabilidad de Medicamentos , Ligandos , Modelos Moleculares , Renio/análisis
9.
Gesundheitswesen ; 69(8-9): 448-56, 2007.
Artículo en Alemán | MEDLINE | ID: mdl-17926261

RESUMEN

TOPIC: We studied those characteristics of mothers that are related to occupational activity two years after the birth of the first child. Differences in the health-related quality of life between working mothers and mothers who are not working were also analysed, taking other parameters into account, in particular household income. METHODOLOGY: 311 mothers with a first child were given a questionnaire on the quality of life based on WHOQOL-BREF, on depression (also surveyed one year before for 139 mothers), on their work situation, socio-demography and other possible confounders. The probability of vocational activity was analysed using logistic regression and the influence of multiple roles on the quality of life was analysed using multiple linear regression. RESULTS: About 60% of mothers were not working two years after the birth of their first child, 25% were working part-time and 11% full time, with 4% in training or education. Working mothers were more likely to have a higher level of education (60% vs. 31%) and less likely to have a household income below the poverty line (13% vs. 47%). The results of the logistic regression showed that the odds ratio for being employed was six times higher for mothers with higher education than mothers with a lower level of education [OR 5.99; 95% confidence interval (CI) 2.58-13.91], whereas the odds ratio for mothers with additional children against those with only one child was 0.14; (95% CI 0.05-0.40), and for mothers with German nationality against those of other ethnicities the odds ratio was 2.37 (95% CI 1.12-5.04). Working mothers give more positive ratings than non-working mothers for their physical and mental quality of life (both p<0.01), their social relationships (p<0.05), as well as their global quality of life and their depression score (p<0.10). Even after adjusting for the depression score one year before working mothers reported less depression (p<0.05). The influence of income on the quality of life was low, except for the assessment of the quality of the environment, and this explains only a small part of the positive effect of the vocational activity. CONCLUSIONS: Vocational activity of mothers of two-year old children reduces the risk of poverty and additionally contributes to an improved physical and mental quality of life of the mother and also to improved social relationships.


Asunto(s)
Empleo/estadística & datos numéricos , Relaciones Madre-Hijo , Madres/estadística & datos numéricos , Calidad de Vida , Rol , Adolescente , Adulto , Escolaridad , Femenino , Alemania/epidemiología , Humanos , Persona de Mediana Edad , Pobreza/estadística & datos numéricos , Clase Social
10.
EJNMMI Radiopharm Chem ; 1(1): 14, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29564390

RESUMEN

BACKGROUND: Bisphosphonates have a high adsorption on calcified tissues and are commonly used in the treatment of bone disorder diseases. Conjugates of bisphosphonates with macrocyclic chelators open new possibilities in bone targeted radionuclide imaging and therapy. Subsequent to positron emission tomography (PET) examinations utilizing 68Ga-labelled analogues, endoradiotheraphy with 177Lu-labelled macrocyclic bisphosphonates may have a great potential in the treatment of painful skeletal metastases. METHODS: Based on the established pharmaceuticals pamidronate and zoledronate two new DOTA-α-OH-bisphosphonates, DOTAPAM and DOTAZOL(MM1.MZ) were successfully synthesized. The ligands were labelled with the positron emitting nuclide 68Ga and the ß- emitting nuclide 177Lu and compared in in vitro studies and in ex vivo biodistribution studies together with small animal PET and single photon emission computed tomography (SPECT) studies against [18F]NaF and a known DOTA-α-H-bisphosphonate conjugate (BPAPD) in healthy Wistar rats. RESULTS: The new DOTA-bisphosphonates can be labelled in high yield of 80 to 95 % in 15 min with post-processed 68Ga and >98 % with 177Lu. The tracers showed very low uptake in soft tissue, a fast renal clearance and a high accumulation on bone. The best compound was [68Ga]DOTAZOL (SUV Femur = 5.4 ± 0.6) followed by [18F]NaF (SUV Femur = 4.8 ± 0.2), [68Ga]DOTAPAM (SUV Femur = 4.5 ± 0.2) and [68Ga]BPAPD (SUV Femur = 3.2 ± 0.3). [177Lu]DOTAZOL showed a similar distribution as the diagnostic 68Ga complex. CONCLUSION: The 68Ga labelled compounds showed a promising pharmacokinetics, with similar uptake profile and distribution kinetics. Bone accumulation was highest for [68Ga]DOTAZOL, which makes this compound probably an interesting bone targeting agent for a therapeutic approach with 177Lu. The therapeutic compound [177Lu]DOTAZOL showed a high target-to-background ratio. SPECT experiments showed concordance to the PET scans in healthy rats. [68Ga/177Lu]DOTAZOL appears to be a potential theranostic combination in the management of disseminated bone metastases.

11.
Anticancer Res ; 26(5A): 3527-33, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17094477

RESUMEN

BACKGROUND: Peptide receptors seem to be good markers for receptor targeting because of their overexpression in human cancer. Understanding the role of receptors and their cognate ligands, they are currently used for both diagnosis and therapy. Candidates playing a key role in tumor biology are the neurotensin receptors (NTR). The expression of NTR in HT-29 cells (human colon adenocarcinoma cell line), FaDu cells (human squamous cell carcinoma cell line) and in corresponding tumor xenografts on nude mice, was investigated. MATERIALS AND METHODS: Quantitative RT-PCR of the three receptor subtypes was carried out to study mRNA expression. Receptor protein expression was analyzed by immunohistochemistry with specific antibodies for the three known neurotensin receptors NTR1, NTR2 and NTR3. RESULTS: Analysis of receptor mRNA revealed a strong expression of NTR3 and a weak expression of NTR1 and NTR2 in cultured cells and xenografts. Examining the protein levels, a strong signal for NTR1 was detected in tumor cells and xenografts and only a weak signal was detected for NTR3. CONCLUSION: Since the receptor protein is targeted in vivo, the enhanced protein expression of NTR1 in xenografts could be a useful tool for molecular targeting with radioligands and for further characterization of the carcinogenic process.


Asunto(s)
Adenocarcinoma/metabolismo , Carcinoma de Células Escamosas/metabolismo , Receptores de Neurotensina/metabolismo , Adenocarcinoma/genética , Animales , Butiratos/farmacología , Carcinoma de Células Escamosas/genética , Diferenciación Celular , Neoplasias del Colon/genética , Neoplasias del Colon/metabolismo , Femenino , Células HT29 , Humanos , Neoplasias Hipofaríngeas/genética , Neoplasias Hipofaríngeas/metabolismo , Masculino , Ratones , Ratones Desnudos , Receptores de Neurotensina/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Tumorales Cultivadas
12.
Geburtshilfe Frauenheilkd ; 75(8): 819-826, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26366001

RESUMEN

Introduction: Preterm birth is a global scourge, the leading cause of perinatal mortality and morbidity. This study set out to identify the principal risk factors for preterm birth, based on the German Health Interview and Examination Survey for Children and Adolescents (KiGGS). A range of possible factors influencing preterm birth were selected for inclusion in the questionnaire, covering factors such as gender, national origin, immigrant background, demography, living standard, family structure, parental education and vocational training. Methods: All data were taken from the aforementioned KiGGS survey conducted between 2003 and 2006. A total of 17 641 children and adolescents (8656 girls and 8985 boys) drawn from 167 German towns and municipalities deemed to be representative of the Federal Republic of Germany were included in the study. Gestational age at birth was available for 14 234 datasets. The questionnaire included questions from the following areas as possible factors influencing preterm birth: gender, national origins, immigrant background, demography, living standard, family structure, parental education and vocational training. Results: The preterm birth rate was 11.6 %, higher than that of other national statistical evaluations. Around 57.4 % of multiple pregnancies and 10 % of singleton pregnancies resulted in preterm delivery. Multiple pregnancy was found to be the most important risk factor (OR 13.116). With regard to national origins and immigration background, mothers from Turkey, the Middle East, and North Africa had a higher incidence of preterm birth. Preterm birth was more prevalent in cities and large towns than in small towns and villages. Conclusion: Risk factors associated with preterm birth were identified. These should help with the early identification of pregnant women at risk. The preterm birth rate in our survey was higher than that found in other national statistical evaluations based on process data. More than half of all multiple pregnancies ended in preterm birth.

13.
Neurobiol Aging ; 24(2): 365-78, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12498971

RESUMEN

Transgenic APP23 mice expressing human APP(751) with the K670N/M671L mutation, were compared at ages 3, 18 or 25 months to non-transgenic littermates in passive avoidance and in a small and large Morris maze. The task in the smaller pool habituated their flight response to the platform. Impairments in passive avoidance and small pool performance in APP23 mice were clearly age-related. In the larger Morris maze APP23 mice at all ages were impaired in latency and distance swum before finding the platform. Identical performance of 18-month APP23 and controls in a visible platform condition indicates that the Morris maze performance deficit was not due to sensory, motor or motivational alterations. At age 3 months both groups initially unexpectedly avoided the visible platform, suggesting that in young mice neophobia may contribute significantly to performance in cognitive tests. In conclusion, APP23 mice exhibit both early behavioral impairment in the large Morris maze as well as impairments in passive avoidance and small pool performance that are marked only in old age.


Asunto(s)
Envejecimiento/fisiología , Precursor de Proteína beta-Amiloide/genética , Cognición/fisiología , Envejecimiento/patología , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/fisiopatología , Animales , Reacción de Prevención/fisiología , Conducta Animal/fisiología , Femenino , Hipocampo/patología , Hipocampo/fisiología , Masculino , Aprendizaje por Laberinto/fisiología , Memoria/fisiología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Neocórtex/patología , Neocórtex/fisiología , Natación
14.
Neuropsychopharmacology ; 28(11): 2010-9, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12931143

RESUMEN

The radiolabeled serotonin transporter (SERT) ligand [(11)C](+)-McN5652 has recently been used in clinical positron emission tomography (PET) studies for SERT imaging. However, this radioligand offers disadvantages in routine clinical settings because of its short radioisotope half-life (eg PET facilities within hospitals without a cyclotron need to acquire such radioligands from distant cyclotron units for clinical use). S-([(18)F]fluoromethyl)-(+)-McN5652 ([(18)F](+)-FMe-McN5652) is an analogue which has been synthesized newly, and has a significantly longer radioisotope half-life. In the porcine brain, it demonstrates the same characteristic distribution pattern of serotonin-uptake sites like the (11)C-labeled congener with the highest binding in the midbrain and thalamus and the lowest in the cerebellum and occipital cortex. It shows a 30% higher blood-brain transfer and a slower peripheral metabolism than [(11)C](+)-McN5652. Rather uniform brain binding was observed after injection of the pharmacologically inactive radiolabeled enantiomer, or after pretreatment with the highly selective SERT inhibitor citalopram. The norepinephrine uptake inhibitor maprotiline did not show any inhibitory effect. Using a one-tissue compartment model (K(1), k"(2)) or a two-tissue compartment model (K(1) to k(4)) with or without constraints for calculation, the regional binding parameters of [(11)C](+)-McN5652 and [(18)F](+)-FMe-McN5652 are highly correlated among each other and with the SERT density, as determined by in vitro binding of [(3)H]citalopram. Using constraints to correct for the free fraction and nonspecific binding of the radiotracers, a considerable increase of the midbrain-occipital cortex ratios with higher values for [(18)F](+)-FMe-McN5652 compared to [(11)C](+)McN5652 was revealed. It is concluded that [(18)F](+)-FMe-McN5652 has better features than [(11)C](+)McN5652 for SERT imaging with PET.


Asunto(s)
Encéfalo/metabolismo , Proteínas Portadoras/análisis , Radioisótopos de Flúor , Isoquinolinas/metabolismo , Glicoproteínas de Membrana/análisis , Proteínas de Transporte de Membrana , Proteínas del Tejido Nervioso , Animales , Femenino , Unión Proteica , Proteínas de Transporte de Serotonina en la Membrana Plasmática , Porcinos , Tomografía Computarizada de Emisión/métodos
15.
J Med Chem ; 33(2): 492-504, 1990 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2299619

RESUMEN

The synthesis and antihypertensive activity of 4-(1,2-dihydro-2-oxo-1-pyridyl)-2H-1-benzopyran-3-ols are described. The unsubstituted pyridone adduct lead compound 7e is highly active, with substituents on the pyridone ring leading to a decrease in activity. Strongly electron-withdrawing substituents at the C-6 position are required for optimal activity. When the 2-pyridone ring is replaced by other heterocycles such as 4-pyridone, pyrimidone, pyridazinone, pyrazinone, and 1,4-butanesultam, the activity is maintained. The removal of the 3-hydroxy function (----17a) does not significantly reduce the activity. The elimination of water from the chromanols leads to the formation of the chromenes, which are among the most potent antihypertensives known. The influence of diverse substituents, in particular heterocyclic C-6 substituents, was investigated in the 4-(2-oxo-1-pyrrolidinyl)chroman-3-ol series. Chromanols esterified at the 3-hydroxy group with short-chain acids, maintain their activity. The epoxidation of the chromene double bond also produces active compounds. The rearrangement of the epoxides 22 produces the 3-keto compounds 23 and the enol derivatives 25. The reduction of the ketone 23a produces cis-chromanol 7ab along with its trans isomer 7e. All compounds were tested for oral antihypertensive activity in spontaneously hypertensive rats with a dose of 1 mg/kg; for selected compounds ED30 values as well as the duration of the antihypertensive effect were determined. 4-(1,2-Dihydro-2-oxo-1-pyridyl)-2,2-dimethyl-2H-1-benzopyran-6- carbonitrile (18a) is under development as a coronary vasodilator and a drug for treating angina pectoris.


Asunto(s)
Antihipertensivos/síntesis química , Benzopiranos/síntesis química , Dihidropiridinas/síntesis química , Canales de Potasio/efectos de los fármacos , Animales , Antihipertensivos/farmacología , Benzopiranos/farmacología , Fenómenos Químicos , Química , Dihidropiridinas/farmacología , Ratas , Ratas Endogámicas SHR , Relación Estructura-Actividad
16.
J Med Chem ; 33(10): 2759-67, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2213828

RESUMEN

The reaction of 2,4-dihydroxypyridine (2) with 3,4-epoxy-3,4-dihydro-2,2-dimethyl-2H-1-benzopyran-6-carbonitrile (1) yielded the 4-[(1,2-dihydro-2-oxo-4-pyridyl)oxy] compound 3a, accompanied by small amounts of the isomeric 4-(1,2-dihydro-4-hydroxy-2-oxo-1-pyridyl) compound 4. This could also be prepared by hydrogenation of the benzyloxy derivative 5. Reaction of 3,6-pyridazinediol (10) with 1 (R = CN) gave the 4-[(1,6-dihydro-6-oxo-3-pyridazinyl)oxy] compound 11a, which in turn rearranged on heating with NaH in DMSO into the 4-(1,6-dihydro-3-hydroxy-6-oxo-1-pyridazinyl) compound 12. A series of 6-substituted analogues (R = CO2Me, CSNH2, NO2, Br) of 3a and 11a were synthesized. N-Alkylation led to compounds 14a-c (R = Me, Et, CHMe2). The 4-heterocyclyloxychromenes 9 and 16a were obtained by alkaline hydrolysis of their 3-camphorsulfonates. The racemic pyridazinyloxy compounds 11a and 14a could be resolved via their diastereomeric camphorsulfonates or camphanates. The differences between the 4-heterocyclyloxychromanols and the isomeric N-substituted compounds 4 and 12 were elucidated in the course of extensive NMR investigations. While in DMSO the former appeared to be conformationally flexible molecules the latter were rigid. All compounds were tested for oral antihypertensive activity in spontaneously hypertensive rats, using doses of 1 mg/kg. High and long lasting activities were found for the pyridyloxy compounds 3a and 3d, the pyridazinyloxy compound 11a, and its N-alkylation products, as well as for the 3S,4R-enantiomers 20a and 22a. (-)-(3S,4R)-3,4-Dihydro-4-[(1,6-dihydro-1-methyl-6-oxo-3- pyridazinyl)oxy]-3-hydroxy-2,2-dimethyl-2H-1-benzopyran-6-carbonitrile (22a) was selected for further development.


Asunto(s)
Antihipertensivos/síntesis química , Benzopiranos/síntesis química , Canales de Potasio/efectos de los fármacos , Animales , Antihipertensivos/química , Benzopiranos/química , Fenómenos Químicos , Química Física , Cristalografía , Relación Dosis-Respuesta a Droga , Espectroscopía de Resonancia Magnética , Estructura Molecular , Ratas , Ratas Endogámicas SHR , Relación Estructura-Actividad , Difracción de Rayos X
17.
Transplantation ; 57(3): 358-63, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8108870

RESUMEN

The pharmacologic modulation of the platelet-activating factor antagonist WEB 2086BS on the release of metabolites of the arachidonic acid and the cytokine TNF alpha was investigated in an ex vivo xenograft model of hyperacute rejection. Pig kidneys were perfused for 60 min in a perfusion system with oxygenated heparinized human or autologous porcine blood, respectively. During autologous perfusion, no alterations in the mediator response could be detected, whereas xenogeneic perfusion induced progressive release of mediators. Treatment by the platelet-activating factor antagonist WEB 2086BS resulted in a significantly reduced liberation of the cytokine TNF alpha and of prostanoids. The histological findings verified that a hyperacute rejection in the xenogeneic perfused organs had occurred, which was mitigated by the treatment with WEB 2086BS. This observation confirms that inflammatory mediators play a decisive role in hyperacute xenogeneic rejection. The results suggest that suppression or manipulation of mediator-specific tissue receptors by receptor-antagonists could be an additional therapeutic mode to control hyperacute rejection in xenogeneic transplantation.


Asunto(s)
Azepinas/farmacología , Trasplante de Riñón/inmunología , Factor de Activación Plaquetaria/antagonistas & inhibidores , Trasplante Heterólogo/fisiología , Triazoles/farmacología , Adulto , Animales , Anticuerpos Heterófilos/sangre , Formación de Anticuerpos , Femenino , Rechazo de Injerto , Hematócrito , Hemoglobinas/análisis , Humanos , Inflamación/fisiopatología , Riñón/irrigación sanguínea , Riñón/patología , Masculino , Perfusión , Presión , Prostaglandinas/metabolismo , Porcinos , Factor de Necrosis Tumoral alfa/metabolismo , Resistencia Vascular
18.
Neuroscience ; 91(4): 1425-33, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10391448

RESUMEN

Inflammation results in a local increase in nerve growth factor production which potentially can modify the properties of nerve growth factor-responsive sensory neurons innervating the inflamed tissue. The sensitivity of primary sensory neurons to the neurotoxin capsaicin is regulated in vitro by nerve growth factor and we have now investigated the effect of complete Freund's adjuvant-induced inflammation on the capsaicin sensitivity of adult rat sensory neurons. Dorsal root ganglion neurons innervating inflamed tissue were identified in vivo by retrograde labelling with the dye Fast Blue. Neuronal capsaicin sensitivity was measured in vitro with a quantitative cobalt-uptake densitometric technique, and was shown to increase significantly five days after inflammation. This increase in sensitivity was dependent on nerve growth factor as it could be inhibited by systemic treatment with nerve growth factor neutralizing antibodies. The enhanced capsaicin sensitivity that results from Freund's adjuvant injection may contribute to inflammatory hyperalgesia.


Asunto(s)
Capsaicina/farmacología , Ganglios Espinales/efectos de los fármacos , Ganglios Espinales/fisiopatología , Inflamación/fisiopatología , Factores de Crecimiento Nervioso/fisiología , Neuronas Aferentes/efectos de los fármacos , Amidinas , Animales , Células Cultivadas , Densitometría/métodos , Colorantes Fluorescentes , Pie , Ganglios Espinales/patología , Masculino , Factores de Crecimiento Nervioso/antagonistas & inhibidores , Neuronas Aferentes/fisiología , Ratas , Ratas Sprague-Dawley
19.
J Clin Pathol ; 56(8): 622-3, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12890816

RESUMEN

gamma-Glutamyl-semialdehyde (gammaGSA) is a major product of the metal catalysed oxidation of apolipoprotein B-100 (apoB-100) proline and arginine residues. On reduction, gammaGSA forms 5-hydroxy-2-aminovaleric acid (HAVA). This report describes the application of HAVA measurement to characterise the formation of gammaGSA in low density lipoprotein (LDL) recovered from human atherosclerotic lesions. HAVA concentrations were greatly increased in LDL from early (mean, 10.25; SD, 3.49 mol/mol apoB-100; p < 0.01), intermediate (mean, 11.18; SD, 2.37 mol/mol apoB-100; p < 0.01), and advanced (mean, 9.91; SD, 2.15 mol/mol apoB-100; p < 0.01) lesions, when compared with LDL from normal aortic tissue (mean, 0.05; SD, 0.01 mol/mol apoB-100). These findings support the hypothesis that pathways involving metal catalysed oxidation of LDL apoB-100 are of pathological importance in atherogenesis.


Asunto(s)
Aminoácidos/análisis , Apolipoproteínas B/metabolismo , Arginina/metabolismo , Arteriosclerosis/metabolismo , Prolina/metabolismo , Adulto , Aorta Torácica , Apolipoproteína B-100 , Biomarcadores/análisis , Catálisis , Glutamatos/metabolismo , Humanos , Lipoproteínas LDL/metabolismo , Masculino , Metales/metabolismo , Persona de Mediana Edad , Oxidación-Reducción
20.
Neuroreport ; 7(8): 1405-8, 1996 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-8856686

RESUMEN

Serotonin (5-HT) is an important signal molecule not only for neurones but also for a variety of other cell types. Targeting the brain endothelium, the constitutive element of the blood-brain barrier (BBB), it elicits permeability changes. Using the selective 5-HT uptake inhibitor [3H]paroxetine we demonstrated the presence of a 5-HT transporter-like protein at the BBB. The binding capacities (Bmax) at the BBB (382 fmol mg-1) and on caudate nucleus membranes (392 fmol mg-1) were similar. However, the binding affinities differed by a factor of 5 (membranes: Kd = 0.10 nM, BBB: 0.47 nM). The affinities of various specific uptake inhibitors were also 2- to 13-fold lower in the microvessel preparation. It is suggested that the 5-HT transporter(s) in the brain and microvessels are different or differently regulated proteins.


Asunto(s)
Núcleo Caudado/metabolismo , Endotelio Vascular/metabolismo , Paroxetina/metabolismo , Animales , Unión Competitiva , Núcleo Caudado/irrigación sanguínea , Microcirculación/metabolismo , Ensayo de Unión Radioligante , Porcinos , Tritio
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