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1.
J Endocrinol Invest ; 44(11): 2327-2332, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34235707

RESUMEN

AIM: Information on systolic dysfunction, as assessed by left-ventricular (LV) mechanics, in patients with pheochromocytoma after surgical treatment is scanty. We performed a systematic meta-analysis of speckle tracking echocardiographic studies to provide an updated comprehensive information on this issue. METHODS: The PubMed, OVID-MEDLINE, and Cochrane library databases were analyzed to search for articles published from the inception up to May 31st 2021. Studies were identified using MeSH terms and crossing the following search items: "myocardial strain" "left ventricular mechanics", "speckle tracking echocardiography", "systolic dysfunction", "pheochromocytoma", and "paraganglioma". RESULTS: A total of 92 surgically treated patients with pheochromocytoma/paraganglioma were included in 3 longitudinal studies. Successful surgical treatment was associated with a decrease in relative wall thickness (SMD - 0.25 ± 0.10, CI - 0.45/- 0.05, p < 0.01) and an improvement in global longitudinal strain (SMD - 0.45 ± 0.10, CI - 0.66/- 0.24, p < 0.0001). The favorable effects of treatment on LV geometry and mechanics were not accompanied by significant changes in ejection fraction (SMD - 0.07 ± 0.10, CI - 0.27/0.12, p = 0.44). CONCLUSIONS: This meta-analysis adds a new piece of evidence, suggesting that surgical treatment of patients with pheochromocytoma impacts favorably on LV geometry and LV mechanics, and, more importantly, the assessment of LV changes in this setting can no longer rely on conventional echocardiographic parameters such as ejection fraction.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales , Ecocardiografía/métodos , Paraganglioma , Feocromocitoma , Procedimientos Quirúrgicos Operativos , Disfunción Ventricular Izquierda , Neoplasias de las Glándulas Suprarrenales/fisiopatología , Neoplasias de las Glándulas Suprarrenales/cirugía , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/patología , Humanos , Evaluación de Resultado en la Atención de Salud , Paraganglioma/fisiopatología , Paraganglioma/cirugía , Feocromocitoma/fisiopatología , Feocromocitoma/cirugía , Procedimientos Quirúrgicos Operativos/métodos , Procedimientos Quirúrgicos Operativos/estadística & datos numéricos , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/fisiopatología
2.
Cytopathology ; 28(4): 307-311, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28685876

RESUMEN

OBJECTIVE: To report two cases of Merkel cell carcinoma (MCC) metastatic to the pancreas diagnosed with endoscopic ultrasound-guided-fine needle aspiration (EUS-FNA) and to add the case of concomitant chronic lymphocytic leukaemia/small lymphocytic lymphoma (CLL/SLL) and MCC to the literature. The aim is to alert the cytopathologists once more to the problems of differential diagnosis of pancreatic metastasis of MCC and to describe the possibilities of ancillary methods performed on direct cytological smears. METHODS: EUS-FNA procedures were performed according to standard institution protocol, using 22-G needles with cytopathologist on-site. Based on rapid on-site evaluation (ROSE), additional passes were made for immunocytochemistry (ICC). A mini panel of antibodies was used to aid the differential diagnosis. RESULTS: Smears revealed a dispersed pattern of small round cells with scant cytoplasm, round nuclei with inconspicuous nucleoli and occasional nuclear moulding, suspicious of small cell carcinoma. Results of ICC applied to the direct cytological smears were as follows: LCA negative, Cytokeratin (clone MNF116) positive, TTF-1 negative, CD 56 positive, NSE weakly positive, Chromogranin A weakly positive and CK20 positive, in one case in a dot-like perinuclear pattern. The diagnosis of MCC was made. CONCLUSION: Increasing incidence of MCC warrants the inclusion of MCC in the differential diagnosis of tumours of small round blue cell morphology even in unusual sites. The cytomorphological features coupled with an ICC panel are usually enough to make a confident diagnosis of MCC. EUS-FNA is a minimally invasive technique which enables sampling adequate tissue for all the ancillary methods eventually needed to support the diagnosis.


Asunto(s)
Carcinoma de Células de Merkel/diagnóstico por imagen , Carcinoma de Células de Merkel/patología , Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico/métodos , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/secundario , Anciano de 80 o más Años , Antígeno CD56/metabolismo , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/diagnóstico por imagen
3.
Community Dent Health ; 33(2): 100-6, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27352463

RESUMEN

UNLABELLED: Early Childhood Caries (ECC) is the most common, preventable disease of childhood. It can affect children's health and wellbeing and children from migrant families may be at greater risk of developing ECC. OBJECTIVE: To describe ECC in children from migrant families, and explore possible influences. BASIC RESEARCH DESIGN: Cross-sectional analysis of caries data collected as baseline data for an oral health promotion study. PARTICIPANTS: The analysis sample included 630 1-4 year-old children clustered within 481 Iraqi, Lebanese and Pakistani families in Melbourne, Australia. METHOD: Child participants received a community-based visual dental examination. Parents completed a self-administered questionnaire on demographics, ethnicity, and oral health knowledge, behaviour and attitudes. MAIN OUTCOME MEASURE: Child caries experience. Bivariate associations between oral health behaviours and ethnicity were tested for significance using chi-square. Multivariate logistic regression analyses were performed to identify associations with ECC, adjusting for demographic variables and accounting for clustering by family. RESULTS: Overall, 34% of children in the sample experienced caries (both non-cavitated and cavitated). For all caries lesions, parent' length of residence in Australia, consumption of sweet drinks and parental education remained as independent predictors of child caries experience. Adding sugar to drinks was an additional risk factor for cavitation. Ethnicity was associated with some individual oral health behaviours suggesting cultural influences on health, however the relationship was not independent of other predictors. CONCLUSION: Culturally competent oral health promotion interventions should aim to support migrant families with young children, and focus on reducing sweet drink consumption.


Asunto(s)
Caries Dental/epidemiología , Salud Bucal , Migrantes , Adolescente , Adulto , Actitud Frente a la Salud , Bebidas/estadística & datos numéricos , Preescolar , Estudios Transversales , Dieta Cariógena , Sacarosa en la Dieta/administración & dosificación , Escolaridad , Femenino , Conductas Relacionadas con la Salud , Conocimientos, Actitudes y Práctica en Salud , Humanos , Lactante , Irak/etnología , Líbano/etnología , Masculino , Persona de Mediana Edad , Pakistán/etnología , Padres/educación , Padres/psicología , Factores de Riesgo , Cepillado Dental/estadística & datos numéricos , Victoria/epidemiología , Adulto Joven
4.
Front Cardiovasc Med ; 9: 1063070, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36762304

RESUMEN

Background: Evidence regarding favorable treatment of patients with functional mitral regurgitation (FMR) using transcatheter edge-to-edge repair (TEER) is constantly growing. However, there is only few data directly comparing TEER and surgical mitral valve repair (SMVr). Aims: To compare baseline characteristics, short-term and 1-year outcomes in FMR patients undergoing mitral valve (MV) TEER or SMVr using a meta-analytic approach. Methods: Systematic database search identified 1,703 studies reporting on TEER or SMVr for treatment of FMR between January 2010 and December 2020. A meta-analytic approach was used to compare outcomes from single-arm and randomized studies based on measures by means of their corresponding 95% confidence intervals (CI). Statistical significance was assumed if CIs did not overlap. A total of 21 TEER and 37 SMVr studies comprising 4,304 and 3,983 patients were included. Results: Patients in the TEER cohort presented with higher age (72.0 ± 1.7 vs. 64.7 ± 4.7 years, p < 0.001), greater burden of comorbidities like hypertension (p < 0.001), atrial fibrillation (p < 0.001), lung disease (p < 0.001) and chronic renal disease (p = 0.005) as well as poorer left ventricular ejection fraction (30.9 ± 5.7 vs. 36.6 ± 5.3%, p < 0.001). In-hospital mortality was significantly lower with TEER [3% (95%-CI 0.02-0.03) vs. 5% (95%-CI 0.04-0.07)] and 1-year mortality did not differ significantly [18% (95%-CI 0.15-0.21) vs. 11% (0.07-0.18)]. NYHA [1.06 (95%-CI 0.87-1.26) vs. 1.15 (0.74-1.56)] and MR reduction [1.74 (95%-CI 1.52-1.97) vs. 2.08 (1.57-2.59)] were comparable between both cohorts. Conclusion: Despite considerably higher age and comorbidity burden, in-hospital mortality was significantly lower in FMR patients treated with TEER, whereas a tendency toward increased 1-year mortality was observed in this high-risk population. In terms of functional status and MR grade reduction, comparable 1-year results were achieved.

5.
Dig Dis ; 26(4): 377-82, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19188731

RESUMEN

INTRODUCTION: Despite advances in imaging techniques, the differentiation between pancreatic cancer and benign lesions remains difficult. Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is an effective method for providing tissue diagnosis, but problems occur when lesions are small or the cytological diagnosis is indeterminate. AIM: To prospectively evaluate the utility of EUS-FNA in patients with small solid pancreatic lesions and those with initial indeterminate or negative cytological diagnosis. METHODS: During the study period we performed a total of 119 EUS-FNA procedures on 46 patients (mean age 56.3 years) for 47 small solid pancreatic lesions (range 7-30 mm, mean 17.2 mm in diameter). FNAs were performed in the presence of a cytopathologist. If cytological diagnoses were indeterminate, EUS-FNA was repeated within 3 weeks. Diagnoses were confirmed histologically or by follow-up (clinical and imaging: EUS +/- FNA and CT). RESULTS: Localization of the lesions: head 28 (60%), uncinate process 4 (9%), body 11 (23%) and tail 4 (9%). On average, 3.7 passes were performed. We observed no complications. Initial cytological findings were: malignant 17 (36%), benign 21 (45%), and indeterminate 9 (19%). 8 (78%) of the indeterminate findings were confirmed to be malignant on repeated procedures. A diagnosis of pancreatic cancer was subsequently confirmed in 1 patient who had a benign cytological finding. 19 patients underwent surgery. Histology confirmed a neoplasm in all cases. Sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy were 68, 100, 100, 73 and 83%, respectively. After repeated EUS-FNAs of indeterminate findings sensitivity, negative predictive value and diagnostic accuracy rose to 92, 77 and 96%, respectively. CONCLUSION: EUS-FNA is a highly effective method for providing tissue diagnosis in patients with small solid pancreatic masses. Repeated procedures enhanced diagnostic accuracy in indeterminate findings, among which was high percentage of malignancies. EUS-FNA reduced the number of operations in patients with pancreatic solid masses.


Asunto(s)
Endosonografía/métodos , Neoplasias Pancreáticas/diagnóstico por imagen , Neoplasias Pancreáticas/patología , Adulto , Anciano , Biopsia con Aguja Fina , Citodiagnóstico , Demografía , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
7.
Aust Dent J ; 60(2): 200-4, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25989365

RESUMEN

BACKGROUND: This study describes and explores factors related to dental service use among migrant children. METHODS: A cross-sectional analysis of baseline data from Teeth Tales, an exploratory trial implementing a community based child oral health promotion intervention. The sample size and target population was 600 families with 1-4 year old children from Iraqi, Lebanese and Pakistani backgrounds residing in metropolitan Melbourne. Participants were recruited into the study using purposive and snowball sampling techniques. RESULTS: Most (88%; 550/625) children had never visited the dentist (mean (SD) age 3.06 years (1.11)). In the fully adjusted model the variable most significantly associated with child dental visiting was parent reported 'no reason for child to visit the dentist' (OR = 0.07, p < 0.001). Of those children whose parents reported their child had no reason to visit the dentist, 22% (37/165) experienced dental caries with 8% (13/165) at the level of cavitation. CONCLUSIONS: Dental service use by migrant preschool children was very low. The relationship between perceived dental need and dental service use is currently not aligned. One in 10 children of select migrant background had visited a dentist, which is in the context of 1 in 3 with dental caries. To improve utilization, health services should consider organizational cultural competence, outreach and increased engagement with the migrant community.


Asunto(s)
Atención Odontológica/estadística & datos numéricos , Caries Dental/epidemiología , Disparidades en Atención de Salud , Padres , Aceptación de la Atención de Salud , Migrantes , Adolescente , Adulto , Servicios de Salud del Niño , Preescolar , Estudios Transversales , Características Culturales , Caries Dental/prevención & control , Femenino , Necesidades y Demandas de Servicios de Salud , Humanos , Lactante , Irak/etnología , Líbano/etnología , Masculino , Persona de Mediana Edad , Pakistán/etnología , Odontología Pediátrica , Población Urbana , Victoria/epidemiología , Adulto Joven
8.
J Hum Hypertens ; 27(1): 62-70, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21900953

RESUMEN

Dipping and nondipping blood pressure (BP) patterns are associated with different levels of target organ damage and cardiovascular risk. The aim of our investigation was to determine the relationship between different BP patterns (dipping, nondipping, extreme dipping and reverse dipping type) and cardiac structure, and function in hypertensive patients. This cross-sectional study included 376 hypertensive patients. All subjects underwent 24-h ambulatory BP monitoring, and complete two-dimensional, pulsed and tissue Doppler echocardiography. Most of the parameters of the left ventricular (LV) diastolic function (E/A, e'/a', E/e') significantly and progressively deteriorated from the extreme dippers to the dippers and nondippers, and finally to the reverse dippers. In contrast, LV structural parameters (IVS, RWT, LV mass index) showed a statistically important difference only by comparing the dippers and the extreme dippers with the rest of the patients. Simultaneously, the right ventricular (RV) structural parameter (RVT, right ventricular thickness), and most RV diastolic parameters significantly and progressively worsened from the extreme dippers, over the dippers and the nondippers, to the reverse dippers. Daytime and night time systolic BP, nocturnal systolic BP fall, and the nondipping and the reverse dipping status were independently associated with LV and RV structure, as well as with diastolic function. LV and RV structure, and diastolic function were significantly more impaired with the nondippers and the reverse dippers compared with others.


Asunto(s)
Presión Sanguínea , Hipertensión/fisiopatología , Miocardio/patología , Función Ventricular Izquierda , Adulto , Anciano , Monitoreo Ambulatorio de la Presión Arterial , Estudios Transversales , Ecocardiografía Doppler , Femenino , Humanos , Hipertensión/patología , Masculino , Persona de Mediana Edad
9.
J Phys Condens Matter ; 24(13): 135302, 2012 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-22392836

RESUMEN

The electronic structure of GaAs, InAs and InSb nanowires is studied using the six-band and the eight-band k·p models. The effect of the different Luttinger-like parameters (in the eight-band model) on the hole band structure is investigated. Although GaAs nanostructures are often treated within a six-band model because of the large bandgap, it is shown that an eight-band model is necessary for a correct description of its hole spectrum. The camel-back structure usually found in the six-band model is not always present in the eight-band model. This camel-back structure depends on the interaction between light and heavy holes, especially the ones with opposite spin. The latter effect is less pronounced in an eight-band model, but could be very sensitive to the Kane inter-band energy (E(P)) value.


Asunto(s)
Arsenicales/química , Galio/química , Indio/química , Modelos Químicos , Nanoestructuras/química , Nanocables/química , Semiconductores , Electrones , Nanotecnología
10.
Acta Clin Belg ; 67(3): 177-83, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22897065

RESUMEN

BACKGROUND: The aim of this study was to determine which risk factors have an influence on occurrence, clinical and echocardiographic characteristics of patients with idiopathic rupture of the chordae tendineae (RCT). METHODS: The study included 149 patients with diagnosed RCT by transthoracic echocardiography: 90 (60.4%) patients with the idiopathic RCT and 59 (39.6%) subjects with a secondary RCT. Clinical and echocardiographic data were collected for each patient. RESULTS: The univariate logistic regression analysis showed that age > or = 65 (OR 3.76, 95% CI; 1.94-6.18), arterial hypertension (HTA) (OR 7.7, 95% CI: 3.43-16.84), duration > or = 15 (OR 1.14, 95%: 1.04-1.24), uncontrolled HTA (OR 4.72, 95% CI: 2.03-7.39), diabetes (OR 3.22, 95%CI: 1.4-7.37), hypercholesterolemia (OR 1.52, 95% CI: 1.05-2.2), hypertriglyceridaemia (OR 1.99, 95% CI: 1.2-3.28), coronary (OR 5.11, 95% CI: 2.34-9.01) and carotid artery disease (OR 4.35, 95% CI: 1.87-6.89), renal failure (OR 7.25, 95% CI: 1.01-15.23), thickness of interventricular septum (OR 3.25, 95% CI: 1.44-7.58), posterior wall (OR 4.67, 95% CI: 2.21-9.13), and relative wall thickness (OR 2.87, 95% CI: 1.65-4.21) correlated with idiopathic RCT. The multiple logistic regression revealed age > or = 65 (OR 1.06, p < 0.001), HTA (OR 4.93, p = 0.001), HTA > or = 15 years (OR 1.35, p = 0.021), uncontrolled HTA (OR 2.28, p=0.007), coronary artery disease (OR 2.78, p = 0.004), and relative wall thickness (OR 3.45, p = 0.005) as independent predictors of idiopathic RCT. CONCLUSION: Independent predictors of idiopathic RCT are advanced age, HTA, its duration, uncontrolled HTA, coronary artery disease, and relative wall thickness.


Asunto(s)
Cuerdas Tendinosas/lesiones , Factores de Edad , Anciano , Fibrilación Atrial/epidemiología , Enfermedades de las Arterias Carótidas/epidemiología , Cuerdas Tendinosas/diagnóstico por imagen , Cuerdas Tendinosas/cirugía , Enfermedad de la Arteria Coronaria/epidemiología , Diabetes Mellitus/epidemiología , Ecocardiografía , Femenino , Ventrículos Cardíacos/diagnóstico por imagen , Humanos , Hipercolesterolemia/epidemiología , Hipertensión/epidemiología , Hipertrigliceridemia/epidemiología , Modelos Logísticos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Rotura Espontánea
11.
Phys Rev B Condens Matter ; 52(11): 8266-8275, 1995 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-9979826
14.
Nanotechnology ; 19(45): 455401, 2008 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-21832775

RESUMEN

The influence of lateral asymmetry on the electronic structure and optical transitions in elliptical strained InAs nanorings is analyzed in the presence of a perpendicular magnetic field. Two-dimensional rings are assumed to have elliptical inner and outer boundaries oriented in mutually orthogonal directions. The influence of the eccentricity of the ring on the energy levels is analyzed. For large eccentricity of the ring, we do not find any Aharonov-Bohm effect, in contrast to circular rings. Rather, the single-particle states of the electrons and the holes are localized as in two laterally coupled quantum dots formed in the lobes of the nanoring. Our work indicates that the control of shape is important for the existence of the Aharonov-Bohm effect in semiconductor nanorings.

15.
Z Gastroenterol ; 43(6): 581-6, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15986287

RESUMEN

OBJECTIVE: The aim of this study was to determine the prevalence and risk factors for peptic ulcer disease (PUD) in dyspeptic patients with ischemic heart disease (IHD), and to assess whether the healing of PUD before coronary artery bypass grafting (CABG) could reduce the need for urgent postoperative endoscopy. PATIENTS AND METHODS: A series of 894 patients referred to Dubrava University Hospital in Zagreb for elective CABG during the period from May 1998 until April 2001 was prospectively analysed. Dyspepsia was assessed by a questionnaire, PUD by upper gastrointestinal endoscopy, and H. pylori status by histology/Giemsa staining and the rapid urease test. The need for urgent postoperative endoscopy (hematemesis and/or melena, sudden onset of anemia or unexplained epigastric pain) was compared between the prospective study group of 894 patients and a series of 463 patients referred for CABG to Dubrava University Hospital during the period from January 1997 until April 1998. RESULTS: Gastroduodenal dyspepsia predominated in 184 (20.6 %) patients, 142 (77.2 %) of them with Helicobacter (H.) pylori infection and 69 (37.5 %) with verified PUD. Univariate analysis indicated the increased risk of multiple PUD to be related to a previous diagnosis of PUD (OR 3.61, 95 % CI 1.32 - 9.82), H. pylori infection (OR 18.86, 95 % CI 2.31 - 153.98), use of aspirin (OR 5.70; 95 % CI 1.80 - 18.03) and left coronary artery occlusions (3.10, 95 % CI 1.00 - 9.59). Multivariate analysis pointed to H. pylori infection (OR 16.30, 95 % CI 1.57 - 168.53) and left coronary artery occlusions (OR 4.84, 95 % CI 1.05 - 22.30) as independent risk factors for multiple PUD. The OR for urgent postoperative endoscopy due to a major gastrointestinal event was 9.9 (95 % CI 2.2 - 45.1) and the OR for active peptic ulcer with stigmata of recent bleeding was 6.9 (95 % CI 1.4 - 33.1) in the group of patients with IHD who were not submitted to evaluation for dyspepsia prior to elective heart surgery. CONCLUSIONS: In areas with a high prevalence of H. pylori infection, endoscopy and a "search and treat" strategy for IHD patients with dyspepsia before elective cardiac surgery should significantly reduce the need for urgent postoperative endoscopy due to major gastrointestinal events.


Asunto(s)
Dispepsia/epidemiología , Dispepsia/cirugía , Isquemia Miocárdica/epidemiología , Isquemia Miocárdica/cirugía , Úlcera Péptica/cirugía , Medición de Riesgo/métodos , Comorbilidad , Puente de Arteria Coronaria/estadística & datos numéricos , Croacia/epidemiología , Dispepsia/diagnóstico , Gastroscopía/estadística & datos numéricos , Humanos , Úlcera Péptica/diagnóstico , Prevalencia , Factores de Riesgo , Encuestas y Cuestionarios , Resultado del Tratamiento
16.
Biochemistry ; 33(35): 10630-7, 1994 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-8075063

RESUMEN

The ultrafast radical clock probe trans-1-methyl-2-phenylcyclopropane (1CH3) and its mono-, di-, and trideuteriomethyl analogues were oxidized by phenobarbital-induced rat liver microsomal enzymes. This cytochrome P450-catalyzed hydroxylation of 1CH3 gave three products: the alcohol trans-(2-phenylcyclopropyl)methanol (2), the rearranged alcohol 1-phenylbut-3-en-1-ol (3), and the phenol trans-2-(p-hydroxyphenyl)-1-methylcyclopropane (4). The identification of both the unrearranged and rearranged products of oxidation, 2 and 3, is consistent with the formation of a radical intermediate via a hydrogen atom abstraction from the methyl group by the catalytically active iron-oxo center. Hydroxylation of three deuteriomethyl forms of 1CH3 produced the analogous deuterated products, although in different amounts of each. Perdeuteration of the methyl group (1CD3) disfavored oxidation at the methyl group and caused an increase in the oxidation of the phenyl ring (metabolic switching). By comparing the amounts of alcohols and phenol formed from the individual, noncompetitive oxidation of 1CH3 and 1CD3 the overall (i.e., combined primary and secondary) deuterium kinetic isotope effect (DKIE) was found to be 12.5. Intramolecular DKIEs for 1CHD2 and 1CH2D were 2.9 and 13.2, respectively. From these results, the primary and secondary DKIEs were calculated to be 7.87 and 1.26, respectively, values that indicate that there is extensive C--H bond stretching in the transition state for the rate-controlling step in P450-catalyzed hydroxylation of 1CH3.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Sistema Enzimático del Citocromo P-450/metabolismo , Hidrocarburos/metabolismo , Animales , Deuterio , Hidroxilación , Técnicas In Vitro , Cinética , Masculino , Microsomas Hepáticos/metabolismo , Ratas , Ratas Endogámicas F344
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