RESUMEN
BACKGROUND: The optimal timing of radiotherapy (RT) after radical prostatectomy for prostate cancer has been uncertain. RADICALS-RT compared efficacy and safety of adjuvant RT versus an observation policy with salvage RT for prostate-specific antigen (PSA) failure. PATIENTS AND METHODS: RADICALS-RT was a randomised controlled trial enrolling patients with ≥1 risk factor (pT3/4, Gleason 7-10, positive margins, preoperative PSA≥10 ng/ml) for recurrence after radical prostatectomy. Patients were randomised 1:1 to adjuvant RT ('Adjuvant-RT') or an observation policy with salvage RT for PSA failure ('Salvage-RT') defined as PSA≥0.1 ng/ml or three consecutive rises. Stratification factors were Gleason score, margin status, planned RT schedule (52.5 Gy/20 fractions or 66 Gy/33 fractions) and treatment centre. The primary outcome measure was freedom-from-distant-metastasis (FFDM), designed with 80% power to detect an improvement from 90% with Salvage-RT (control) to 95% at 10 years with Adjuvant-RT. Secondary outcome measures were biochemical progression-free survival, freedom from non-protocol hormone therapy, safety and patient-reported outcomes. Standard survival analysis methods were used; hazard ratio (HR)<1 favours Adjuvant-RT. RESULTS: Between October 2007 and December 2016, 1396 participants from UK, Denmark, Canada and Ireland were randomised: 699 Salvage-RT, 697 Adjuvant-RT. Allocated groups were balanced with a median age of 65 years. Ninety-three percent (649/697) Adjuvant-RT reported RT within 6 months after randomisation; 39% (270/699) Salvage-RT reported RT during follow-up. Median follow-up was 7.8 years. With 80 distant metastasis events, 10-year FFDM was 93% for Adjuvant-RT and 90% for Salvage-RT: HR=0.68 [95% confidence interval (CI) 0.43-1.07, P=0.095]. Of 109 deaths, 17 were due to prostate cancer. Overall survival was not improved (HR=0.980, 95% CI 0.667-1.440, P=0.917). Adjuvant-RT reported worse urinary and faecal incontinence 1 year after randomisation (P=0.001); faecal incontinence remained significant after 10 years (P=0.017). CONCLUSION: Long-term results from RADICALS-RT confirm adjuvant RT after radical prostatectomy increases the risk of urinary and bowel morbidity, but does not meaningfully improve disease control. An observation policy with salvage RT for PSA failure should be the current standard after radical prostatectomy. TRIAL IDENTIFICATION: RADICALS, RADICALS-RT, ISRCTN40814031, NCT00541047.
Asunto(s)
Prostatectomía , Neoplasias de la Próstata , Terapia Recuperativa , Humanos , Masculino , Prostatectomía/métodos , Neoplasias de la Próstata/radioterapia , Neoplasias de la Próstata/cirugía , Neoplasias de la Próstata/patología , Anciano , Terapia Recuperativa/métodos , Persona de Mediana Edad , Radioterapia Adyuvante/efectos adversos , Radioterapia Adyuvante/métodos , Antígeno Prostático Específico/sangre , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/prevención & control , Clasificación del Tumor , Factores de TiempoRESUMEN
INTRODUCTION: To examine electroencephalogram (EEG) as a diagnostic tool for late-onset efavirenz (EFV) neurotoxicity syndrome (LENS), an uncommon but severe and potentially fatal complication of EFV therapy. METHODS: We conducted a Retrospective case-control study. EEGs from confirmed cases of LENS (clinical syndrome and plasma EFV >4ug/mL) recorded from June 2016 to May 2021 were compared with control EEGs from the same time-period. Controls were adults (18-70 years) with a similar indication for EEG (eg. encephalopathy or confusion), dysrhythmia generalised grade II, and LENS excluded. EEGs were reviewed by two blinded interpreters given a description of the characteristic EEG changes, ie. persistent, diffuse, high voltage, bisynchronous, monomorphic 4-7 Hz theta frequency waveforms with transient attenuation on eye opening. Interpreters were asked to determine whether EEGs showed definite, probable or no changes. RESULTS: Thirteen LENS cases were compared with 50 control EEGs. Interpreter 1 labelled 11/13 LENS cases as having define or probable changes, and interpreter 2 labelled 10/13. Interpreter 1 labelled probable changes in 1/50 controls and interpreter 2 in 3/50. Neither interpreter labelled any controls as having definite changes. Interrater reliability was good with 95% agreement and a Cohen's kappa of 0.83. Sensitivity of EEG under these conditions for the diagnosis of LENS was 85% and 77% for interpreters 1 and 2 respectively, and specificity was 98% and 94%. CONCLUSIONS: EEG is a useful tool in the diagnosis of LENS which can be used to aid clinical decisions while awaiting EFV levels, or in low-resource settings where EFV levels are not available.
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Electroencefalografía , Síndromes de Neurotoxicidad , Adulto , Humanos , Estudios Retrospectivos , Estudios de Casos y Controles , Reproducibilidad de los Resultados , Síndromes de Neurotoxicidad/diagnóstico , Síndromes de Neurotoxicidad/etiologíaRESUMEN
Foodborne diseases (FBDs) have a large disease burden among children. The major type of FBD in children is diarrhea, caused mainly by contaminated food. One of the diarrhea pathogens is Diarrheagenic Escherichia coli (DEC). The aim of this study was to establish a model of microbial prediction (DEC) in stool, caused by the transmission of FBDs in elementary schoolchildren. An observational analytic study was conducted, with a nested case-control study design. In Stage I, the study population was children in a selected elementary school at Surabaya. The sample size for Stage I was 218 children. In Stage II, the case sample was all children with a positive test for DEC (15 children), and the control sample was all children who had tested negative for DEC (60 children). The result of the laboratory tests showed that the proportion of DEC in children was 6.88% (15 of 218 children) and the proportion of Escherichia coli O157:H7 in children was only 0.46%. The most significant mode of transmission included in the model was the snacking frequency at school and the risk classification of food that was often purchased at school. The formulation of the predicting model of DEC in stool can be used as an early warning against the incidence of FBDs in elementary schoolchildren.
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Diarrea/microbiología , Infecciones por Escherichia coli/epidemiología , Infecciones por Escherichia coli/transmisión , Escherichia coli/aislamiento & purificación , Enfermedades Transmitidas por los Alimentos/epidemiología , Estudios de Casos y Controles , Niño , Preescolar , Diarrea/epidemiología , Infecciones por Escherichia coli/microbiología , Heces/microbiología , Femenino , Humanos , Indonesia/epidemiología , Masculino , Instituciones AcadémicasRESUMEN
BACKGROUND: At imaging frequencies associated with high-field MRI, the combined effects of increased load-coil interaction and shortened wavelength results in degradation of circular polarization and B1 field homogeneity in the imaging volume. Radio frequency (RF) shimming is known to mitigate the problem of B1 field inhomogeneity. Transmit arrays with well decoupled transmitting elements enable accurate B1 field pattern control using simple, non-iterative algorithms. METHODS: An eight channel transmit array was constructed. Each channel consisted of a transmitting element driven by a dedicated on-coil RF current source. The coil current distributions of characteristic transverse electromagnetic (TEM) coil resonant modes were non-iteratively set up on each transmitting element and 3T MRI images of a mineral oil phantom were obtained. RESULTS: B1 field patterns of several linear and quadrature TEM coil resonant modes that typically occur at different resonant frequencies were replicated at 128 MHz without having to retune the transmit array. The generated B1 field patterns agreed well with simulation in most cases. CONCLUSIONS: Independent control of current amplitude and phase on each transmitting element was demonstrated. The transmit array with on-coil RF current sources enables B1 field shimming in a simple and predictable manner.
RESUMEN
Mebendazole is an antihelminthic drug that exerts its effects via interference with microtubule function in parasites. To determine the utility of mebendazole as a potential treatment for vascular diseases involving proliferation of vascular smooth muscle cells, the effects of mebendazole on vascular smooth muscle cell proliferation were tested in vitro and in a mouse model of arterial injury. In vitro, mebendazole inhibited proliferation and migration of murine vascular smooth muscle cells and this was associated with altered intracellular microtubule organization. To determine in vivo effects of mebendazole following vascular injury, femoral arterial wire injury was induced in wild-type mice treated with either mebendazole or placebo control. Compared with placebo-treated mice, mebendazole-treated mice formed less neointima at the site of injury. Mebendazole is effective at inhibiting vascular smooth muscle cell proliferation and migration, and neointimal formation following arterial injury in mice.
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Mebendazol/farmacología , Músculo Liso Vascular/efectos de los fármacos , Miocitos del Músculo Liso/efectos de los fármacos , Neointima/tratamiento farmacológico , Lesiones del Sistema Vascular/tratamiento farmacológico , Animales , Apoptosis/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Hiperplasia , Masculino , Mebendazol/administración & dosificación , Ratones , Neointima/patología , Lesiones del Sistema Vascular/patologíaRESUMEN
Sickle cell disease (SCD) is associated with vascular complications including premature stroke. The role of atherothrombosis in these vascular complications is unclear. To determine the effect of SCD on atherosclerosis and thrombosis, mice with SCD along with controls were generated by transplantation of bone marrow from mice carrying the homozygous sickle cell mutation (Hbb(hßs/hßs) ) or wild-type mice (Hbb(+/+) ) into C57BL6/J or apolipoprotein E deficient (Apoe(-/-) ) recipient mice. At the time of sacrifice, 23-28 weeks following bone marrow transplantation, anaemia, reticulocytosis, and splenomegaly were present in mice receiving Hbb(hßs/hßs) bone marrow compared with control mice. Analysis of atherosclerosis involving the aortic root revealed reduced atherosclerotic lesion area with reduced macrophage content and increased collagen content in Apoe(-/-) , Hbb(hßs/hßs) mice compared to Apoe(-/-) , Hbb(+/+) mice. In a carotid thrombosis model, the time to thrombosis was prolonged in Hbb(hßs/hßs) mice compared to Hbb(+/+) mice. This apparent protective effect of SCD on atherosclerosis and thrombosis was diminished by inhibition of heme oxygenase-1 (HMOX1) using zinc protoporphyrin IX. We conclude that SCD in mice is paradoxically protective against atherosclerosis and thrombosis, highlighting the complexity of vascular events in SCD. This protective effect is at least partially mediated by induction of HMOX1.
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Anemia de Células Falciformes/genética , Anemia de Células Falciformes/metabolismo , Aterosclerosis/prevención & control , Trombosis/prevención & control , Anemia de Células Falciformes/complicaciones , Animales , Aorta/patología , Apolipoproteínas E/deficiencia , Apolipoproteínas E/genética , Aterosclerosis/etiología , Arterias Carótidas/patología , Modelos Animales de Enfermedad , Hemo-Oxigenasa 1/antagonistas & inhibidores , Hemo-Oxigenasa 1/metabolismo , Lípidos/sangre , Masculino , Ratones , Ratones Noqueados , Protoporfirinas/farmacología , Trombosis/etiologíaRESUMEN
Naegleria fowleri, a free-living, thermophilic amoeba ubiquitous in the environment, causes primary amoebic meningoencephalitis (PAM), a rare but nearly always fatal disease of the central nervous system. While case reports of PAM have been documented worldwide, very few individuals have been diagnosed with PAM despite the vast number of people who have contact with fresh water where N. fowleri may be present. In the USA, 111 PAM case-patients have been prospectively diagnosed, reported, and verified by state health officials since 1962. Consistent with the literature, case reports reveal that N. fowleri infections occur primarily in previously healthy young males exposed to warm recreational waters, especially lakes and ponds, in warm-weather locations during summer months. The annual number of PAM case reports varied, but does not appear to be increasing over time. Because PAM is a rare disease, it is challenging to understand the environmental and host-specific factors associated with infection in order to develop science-based, risk reduction messages for swimmers.
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Amebiasis/epidemiología , Infecciones Protozoarias del Sistema Nervioso Central/epidemiología , Meningoencefalitis/epidemiología , Naegleria fowleri , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Estados Unidos/epidemiología , Adulto JovenRESUMEN
BACKGROUND: Management of colorectal cancer depends on many patient and tumour variables. Decisions are sometimes based on the histological grade of tumour as assessed by initial biopsy. This retrospective study looked at the reliability of grading colorectal cancer from pre-operative biopsies. METHODS: 118 patients with a diagnosis of colorectal cancer, who had adequate pre-operative biopsies, were included in the study. A single consultant histopathologist re-examined all the preoperative biopsy slides, but was blinded to the final grading of the resection specimen. RESULTS: Of the 118 resection specimens, 41 were graded well-differentiated, 52 moderately differentiated and 25 poorly differentiated. When compared with postoperative grading, 37 (31%) initial biopsies were undergraded, 49 (43%) were correctly graded and 32 (26%) were overgraded. CONCLUSIONS: These results suggest that the histological grading of pre-operative specimens is inaccurate and should be used with caution to determine treatment. The difficulty with grading pre-operative biopsies in colorectal cancer may be owing to a lack of specific criteria such as is used in, for example, breast cancer.
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Adenocarcinoma/patología , Neoplasias Colorrectales/patología , Cuidados Preoperatorios/métodos , Biopsia/métodos , Humanos , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y EspecificidadRESUMEN
Incarcerated parents present several risk factors for later violence by their children. This study uses comparison groups and repeated measures to evaluate an inmate parenting program. Subjects are inmates at a county detention center, their children, and primary caregivers. Challenges to program implementation and longitudinal research with inmates were identified, along with recommendations to assist future research and programming. Training material should use illustrated, basic language format. Acceptance and participation by inmates and staff require ongoing outreach and communication. Severed relationships are common and future research on inmates with stable family relationships is recommended. Because of inmate transience, integrating parent training into post-release programming is suggested.
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Padres , Prisioneros , Violencia/prevención & control , Niño , Preescolar , Familia , Humanos , Estudios Longitudinales , Responsabilidad Parental , Padres/psicología , Investigación , Factores de Riesgo , Estados UnidosRESUMEN
Caffeine is known to potentiate the cytotoxicity of a variety of DNA damaging agents presumably by reducing the ability of the cells to repair potentially lethal lesions. However, in the present study we observe that 5 mM caffeine reverses the cell kinetic and cytotoxic effects of the intercalating drug Novantrone (mitoxantrone) on L1210, HL-60 and CHO cells. Novantrone alone, at a concentration of 20-30 ng/ml, given to cultures for 1 h, inhibits cell growth by about 50% and causes cells to accumulate in S and G2 phase and to enter a higher DNA ploidy level. Treatment of these cell lines with 5 mM caffeine alone for 1 h has a minimal effect on cell proliferation; suppression of cell growth varies from 5 to 10%. Exposure of cells to Novantrone for 1 h in the presence of caffeine results in a significant reduction of the Novantrone effects; the cell growth rate is partially restored (e.g. caffeine reduces suppression of L1210 cell growth from 48 to 83% of control) and in each of the cell lines studied, the Novantrone-induced cell accumulation in S and G2 is abolished. Combined treatment with caffeine and Novantrone also increases the clonogenicity of CHO cells 8.5 times over that seen in cultures treated with Novantrone alone. In contrast to the combined treatment with caffeine + Novantrone, pretreatment of cells with caffeine provides no protection. Likewise, post-treatment with caffeine provides little reversal of growth inhibition and G2 cell accumulation, especially if the post-treatment is delayed in time. The present data, in conjunction with evidence in the literature that caffeine protects cells against the cytotoxic effects of doxorubicin, suggest that caffeine may play a more general role in protecting cells against planar aromatic molecules such as intercalating agents.
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Cafeína/farmacología , Mitoxantrona/antagonistas & inhibidores , Animales , Ciclo Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Línea Celular , Combinación de Medicamentos , Humanos , Cinética , Ratones , Mitoxantrona/toxicidad , Factores de Tiempo , Células Tumorales CultivadasRESUMEN
In this study of the reliability and validity of the Children's Depression Adjective Check Lists (C-DACL; Brewer & Lubin, 1987) with emotionally disturbed adolescent boys (N = 50), data were collected on two occasions. Internal consistency (alpha) was .89 and .94 for form H and .89 and .95 for form I. Alternate form reliabilities were .86 and .95. Split-half reliabilities were .80 and .89 for form H and .68 and .86 for form I. Concurrent validity was determined by correlations between C-DACL and the Self-Rating Scale of Depressed Mood. Correlations were .65 and .80 for H and .54 and .80 for I. Data from the present study were tested against data from emotionally disturbed adolescent girls (Sokoloff & Lubin, 1983), with boys scoring significantly lower on both forms (H and I) of the C-DACL.
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Síntomas Afectivos/psicología , Trastorno Depresivo/psicología , Pruebas Psicológicas , Adolescente , Trastornos de la Conducta Infantil/psicología , Femenino , Identidad de Género , Humanos , Masculino , Psicometría , Tratamiento DomiciliarioRESUMEN
The structure of the alpha 1-adrenergic receptor was investigated by comparing polypeptides identified by sodium dodecyl sulfate (NaDodSO4)-polyacrylamide gel electrophoresis with the size of the intact receptor in cell membranes as determined by target size analysis. The alpha 1-adrenergic receptor from rat liver membranes affinity-labeled with [3H]phenoxybenzamine, a covalent affinity reagent, appeared as a single polypeptide with a molecular mass of 85,000 daltons (Da) on NaDodSO4-polyacrylamide gels. In the absence of protease inhibitors, smaller peptides of 58-62 kDa and 40-45 kDa, specifically labeled with [3H]phenoxybenzamine, were also apparent on NaDodSO4 gels. In order to determine whether the 85-kDa protein represented all or only a portion of the alpha 1-receptor, radiation inactivation (target size analysis) was undertaken. Radiation-induced receptor inactivation was measured by the loss of specific [3H]phenoxybenzamine and [3H]prazosin binding and by the loss of affinity-labeled alpha 1-adrenergic receptors on NaDodSO4 gels. Target size analysis of rat liver alpha 1-receptors indicated that the intact membrane-bound receptor has an average molecular mass of 160,000 Da. These data suggest that the intact alpha-receptor may exist in the membrane as a dimer of two 85,000-Da subunits. The structure of the alpha 1-receptor was further studied by limited proteolysis of the 85-kDa protein isolated from NaDodSO4 gels. Trypsin, chymotrypsin, and papain produce smaller peptides similar to those produced during membrane isolation in the absence of protease inhibition. Limited proteolysis of the membrane-bound receptor produces water-soluble peptides, the largest of which is 45,000 Da. This peptide contains the ligand-binding domain and protrudes from the membrane into the extracellular space.
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Hígado/metabolismo , Receptores Adrenérgicos alfa/aislamiento & purificación , Animales , Unión Competitiva , Membrana Celular/metabolismo , Electroforesis en Gel de Poliacrilamida , Endopeptidasas , Cinética , Peso Molecular , Fragmentos de Péptidos/análisis , Fenoxibenzamina/metabolismo , Ratas , Receptores Adrenérgicos alfa/metabolismo , Receptores Adrenérgicos alfa/efectos de la radiación , SolubilidadRESUMEN
Muscarinic cholinergic receptors isolated from Drosophila heads, rat and human brain, dog heart, and monkey ciliary muscle were examined for structural similarities/differences by utilizing isoelectric focusing, sodium dodecyl sulfate/polyacrylamide gel electrophoresis, and monoclonal antibody crossreactivity. Muscarinic receptors were affinity labeled with [3H]propylbenzilylcholine mustard and subjected to isoelectric focusing. Muscarinic receptors from each species focused with an isoelectric point of 5.9. The same proteins all migrated with an apparent molecular mass of 80,000 daltons on sodium dodecyl sulfate gels. Six hybridomas secreting monoclonal antibodies specific for muscarinic receptors were developed by using purified rat brain muscarinic receptors as the antigen. The six different monoclonal antibodies immunoprecipitated muscarinic receptors from all tissues and species tested, including human and Drosophila brains, with equal efficacy. These data indicate that muscarinic receptors are highly conserved over a considerable evolutionary period. One of the six muscarinic receptor monoclonal antibodies also immunoprecipitated rat liver alpha 1-adrenergic receptors. Furthermore, two out of five monoclonal antibodies raised against alpha 1-receptors immunoprecipitated muscarinic receptors. These data suggest that some degree of structural homology exists between muscarinic cholinergic receptors and alpha 1-adrenergic receptors.
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Encéfalo/metabolismo , Drosophila melanogaster/genética , Receptores Adrenérgicos alfa/genética , Receptores Muscarínicos/genética , Animales , Anticuerpos Monoclonales , Membrana Celular/metabolismo , Perros , Cobayas , Haplorrinos/genética , Humanos , Hígado/metabolismo , Especificidad de Órganos , Ranidae/genética , Ratas , Especificidad de la EspecieAsunto(s)
Anticuerpos Monoclonales , Proteínas Portadoras/aislamiento & purificación , Glucosa/metabolismo , Mucosa Intestinal/metabolismo , Intestino Delgado/metabolismo , Sodio/metabolismo , Animales , Cromatografía de Afinidad , Inmunoquímica , Microvellosidades/metabolismo , Proteínas de Transporte de Monosacáridos , ConejosRESUMEN
The combination of immunological advances with membrane receptor research has promoted rapid progress in the molecular characterization of neurotransmitter receptor molecules. We have to date produced monoclonal antibodies to beta 1-, beta 2-, and alpha 1-adrenergic, D2-dopaminergic, and muscarinic receptors. In addition we have discovered that some allergic respiratory disease patients possess circulating autoantibodies to beta 2-adrenergic receptors. These antireceptor antibodies in conjunction with specific receptor affinity reagents have allowed us to isolate, purify, and begin to characterize alpha- and beta-adrenergic, dopaminergic, and muscarinic receptors. For example, immunoprecipitation of turkey erythrocyte beta 1 receptors with monoclonal antibodies yields a single polypeptide Mr 65--70 K. In contrast, purification of beta 2-adrenergic receptors using either autoantibodies or monoclonal antibodies yields a receptor species with a subunit of Mr 55--59 K. Autoantibodies to beta 2 receptors demonstrate a 50--100% homology among beta 2 receptors from humans to rats, whereas monoclonal antibody FV-104 recognizes a determinant in the ligand binding site of all beta 1 and beta 2 receptors tested to date. These data suggest that beta 1- and beta 2-adrenergic receptors may have evolved from a common ancestor, perhaps by gene duplication.
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Receptores de Neurotransmisores/aislamiento & purificación , Animales , Anticuerpos Monoclonales , Autoanticuerpos , Fenómenos Químicos , Precipitación Química , Química , Inmunoquímica , Focalización Isoeléctrica , Ratones , Ratones Endogámicos BALB C , Receptores Adrenérgicos/aislamiento & purificación , Receptores Muscarínicos/aislamiento & purificación , Bazo/metabolismoRESUMEN
These data indicate a number of similarities between the neurotransmitter receptors of different pharmacological classes. We are pursuing the hypothesis that the neurotransmitter receptors may have evolved from one another and contain constant regions (eg, adenylate cyclase and calcium channel interaction sites) and variable regions (eg, neurotransmitter- or hormone-binding sites). It is clear that monoclonal antibodies are keys to this end.
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Receptores de Neurotransmisores/aislamiento & purificación , Animales , Fenómenos Químicos , Química Física , Humanos , Peso Molecular , Receptores Adrenérgicos alfa/metabolismo , Receptores Adrenérgicos beta/metabolismo , Receptores Colinérgicos/metabolismo , Receptores Dopaminérgicos/metabolismo , Receptores de Neurotransmisores/metabolismo , Receptores de Neurotransmisores/efectos de la radiaciónRESUMEN
The kinetic constants were determined for dopamine (CA) and norepinephrine (NE) metabolism by phenolsulfotransferase (PST), type A and B monoamine oxidase (MAO), and membrane-bound and soluble catechol-O-methyltransferase (COMT) in frontal lobe preparations of human brain. PST and membrane-bound COMT were found to have the lowest Km values for both catecholamines. By means of the appropriate rate equations and the calculated kinetic constants for each enzyme, the activity of each enzymatic pathway was determined at varying concentrations of DA and NE. Results indicate that deamination by MAO is the principal pathway for the enzymatic inactivation of DA whereas NE is largely metabolized by MAO type A and membrane-bound COMT under the in vitro assay conditions used. At concentrations less than 100 microM, soluble COMT contributes less than 5% to the total catabolism of either catecholamine. PST can contribute up to 15% of the total DA metabolism and 7% of NE metabolism.