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1.
J Viral Hepat ; 24(3): 207-215, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28127941

RESUMEN

Successful hepatitis C virus (HCV) therapy depends on effective pathways of care. Over two decades, we have developed four sequential models of care latterly using a multidisciplinary managed care network to improve HCV testing, care and treatment. This was a cohort study to evaluate the effectiveness of care pathways, carried out using all HCV antibody-positive individuals tested in a geographical region between 1994 and 2014. The study involved 3122 HCV-positive patients. They were divided into four subgroups representing different care pathways defined by their date of HCV antibody diagnosis. The number who accessed treatment services within 1 year of diagnosis increased from 77 of 292 (26.3%) to 521 of 821 (72.9%). The rate of treatment starts within 1 year of diagnosis increased from 6 of 292 (2.0%) to 133 of 821 (16.2%), and the sustained viral response rate improved from 61.6% to 77.4%. All-cause mortality decreased from 232 of 688 (33.7%) in subgroup A to 55 of 1207 (4.5%) in subgroup D, and multivariate analysis showed that pathway type was an independent predictor of mortality irrespective of age, sex, SVR status or HIV co-infection with pathway in D having an odds ratio of 0.53(0.40-0.77; P<.001) compared to pathway in A. At study end, 78% (3122) of an estimated 4000 HCV positive had been diagnosed. In total, 97.5% of HCV caseload was referred to specialist services and 89% attended for assessment. The introduction of a managed care network increased access to care and reduced all-cause mortality.


Asunto(s)
Investigación sobre Servicios de Salud , Hepatitis C Crónica/diagnóstico , Hepatitis C Crónica/tratamiento farmacológico , Programas Controlados de Atención en Salud/organización & administración , Adulto , Estudios de Cohortes , Femenino , Humanos , Masculino , Mortalidad , Análisis de Supervivencia , Respuesta Virológica Sostenida , Resultado del Tratamiento , Reino Unido
2.
Am J Transplant ; 13(2): 467-73, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23205765

RESUMEN

Obliterative bronchiolitis (OB) is the primary cause of late morbidity and mortality following lung transplantation. Current animal models do not reliably develop OB pathology. Given the similarities between ferret and human lung biology, we hypothesized an orthotopic ferret lung allograft would develop OB. Orthotopic left lower lobe transplants were successfully performed in 22 outbred domestic ferrets in the absence of immunosuppression (IS; n = 5) and presence of varying IS protocols (n = 17). CT scans were performed to evaluate the allografts. At intervals between 3-6 months the allografts were examined histologically for evidence of acute/chronic rejection. IS protects allografts from acute rejection and early graft loss. Reduction of IS dosage by 50% allowed development of controlled rejection. Allografts developed infiltrates on CT and classic histologic acute rejection and lymphocytic bronchiolitis. Cycling of IS, to induce repeated episodes of controlled rejection, promoted classic histologic hallmarks of OB including fibrosis-associated occlusion of the bronchiolar airways in all allografts of long-term survivors. In conclusion, we have developed an orthotopic lung transplant model in the ferret with documented long-term functional allograft survival. Allografts develop acute rejection and lymphocytic bronchiolitis, similar to humans. Long-term survivors develop histologic changes in the allografts that are hallmarks of OB.


Asunto(s)
Bronquiolitis Obliterante/diagnóstico , Modelos Animales de Enfermedad , Trasplante de Pulmón/métodos , Animales , Hurones , Fibrosis , Rechazo de Injerto , Inmunosupresores/farmacología , Inmunosupresores/uso terapéutico , Linfocitos/citología , Esputo , Factores de Tiempo , Tomografía Computarizada por Rayos X/métodos , Trasplante Homólogo
3.
J Viral Hepat ; 19(2): 112-9, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22239500

RESUMEN

Hepatitis C virus (HCV) is commonly transmitted by intravenous drug use (IDU) but drug users are under represented in many treatment cohorts, this is because of the assumption of lowered treatment success. We assessed HCV treatment outcomes in active intravenous drug users and patients on opiate substitution therapy. The Tayside HCV treatment database was retrospectively analysed for consecutively treated patients based on risk factor for acquisition of HCV. Primary end point was sustained virological response (SVR). Two hundred and ninety-one consecutively treated patients were assessed. The overall SVR rate was 55.3%. The SVR rates by risk factor were; Non-IDU 61.4%, Ex-IDU 54.8% and Active IDU 47.1% (P = n/s). In the groups G1 patients SVR was; Non-IDU 52.7%, Ex-IDU 30.7% and active IDU 35.4% (P = n/s). In the non-G1 patients: non-IDU 65.1%, Ex-IDU 76.7% and active IDU 53.5%. Ex-IDU had a significantly better SVR than active IDU, other differences were not significant. Our results demonstrate that SVR rates in the active drug users and those on opiate substitution therapy can be achieved which are comparable with non-IDU infected individuals. Intravenous drug use in those engaged with treatment services should not be seen as a barrier to treatment of HCV.


Asunto(s)
Antivirales/administración & dosificación , Hepatitis C/complicaciones , Hepatitis C/tratamiento farmacológico , Abuso de Sustancias por Vía Intravenosa/complicaciones , Abuso de Sustancias por Vía Intravenosa/tratamiento farmacológico , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento , Carga Viral
4.
Nat Med ; 7(12): 1347-52, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11726976

RESUMEN

Heart transplant rejection is characterized pathologically by myocyte necrosis and apoptosis associated with interstitial mononuclear cell infiltration. Any one of these components can be targeted for noninvasive detection of transplant rejection. During apoptotic cell death, phosphatidylserine, a phospholipid that is normally confined to the inner leaflet of cell membrane bilayer, gets exteriorized. Technetium-99m-labeled annexin-V, an endogenous protein that has high affinity for binding to phosphatidylserine, has been administered intravenously for noninvasive identification of apoptotic cell death. In the present study of 18 cardiac allograft recipients, 13 patients had negative and five had positive myocardial uptake of annexin. These latter five demonstrated at least moderate transplant rejection and caspase-3 staining, suggesting apoptosis in their biopsy specimens. This study reveals the clinical feasibility and safety of annexin-V imaging for noninvasive detection of transplant rejection by targeting cell membrane phospholipid alterations that are commonly associated with the process of apoptosis.


Asunto(s)
Anexina A5 , Rechazo de Injerto/diagnóstico por imagen , Trasplante de Corazón/diagnóstico por imagen , Trasplante de Corazón/inmunología , Compuestos de Organotecnecio , Cintigrafía/métodos , Adulto , Anciano , Apoptosis , Transporte Biológico , Femenino , Humanos , Inyecciones Intravenosas , Masculino , Persona de Mediana Edad , Miocardio/inmunología , Miocardio/patología
5.
J Viral Hepat ; 17(10): 698-704, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20002561

RESUMEN

Infection with the hepatitis C virus commonly occurs in patient groups who have difficulty accessing conventional medical care, reducing their chance of successful antiviral therapy. Managed care networks (MCNs) have been suggested as a mechanism of improving access to care; however, there is little evidence to support their use in patients with hepatitis C. The aim of this study was to evaluate the impact of a MCN for patients with hepatitis C. This was a retrospective cohort study of all individuals in our area who had received a positive hepatitis C antibody test between August 1994 and June 2008. The MCN introduced a new referral pathway, which included nonmedical referrals and outreach nurse-led clinics. These interventions were introduced in 2004 and evaluated in 2008. After the introduction of the MCN, the proportion of individuals who accessed care increased from 61% (280/430) to 82.4% (721/875). There was an increase in nonmedical referrals with 81 (18.3%) being directly referred from Drug Problem Services and 75 (17%) from the Prison Service. The changes to referral did not have a negative impact on treatment outcomes as the number who completed treatment increased from 66.1% (43/65) to 73.7% (98/133) and the sustained virological response increased from 50.7% (33/65) to 60.9% (81/133). This study provides evidence that the collaboration of health care professionals within a network can have a radical effect in improving access to care in a traditionally hard to reach population. This has been achieved with little additional resource, but rather working smarter with existing staff.


Asunto(s)
Investigación sobre Servicios de Salud , Hepatitis C/terapia , Programas Controlados de Atención en Salud , Adolescente , Adulto , Estudios de Cohortes , Femenino , Humanos , Masculino , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
6.
Science ; 248(4955): 605-7, 1990 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-2159184

RESUMEN

The amino acid sequences of three fragments of cyanogen bromide-digested human placental inositol 1,2-cyclic phosphate 2-phosphohydrolase, an enzyme of the phosphatidylinositol signaling pathway, are identical to sequences within lipocortin III, a member of a family of homologous calcium- and phospholipid-binding proteins that do not have defined physiological functions. Lipocortin III has also been previously identified as placental anticoagulant protein III (PAP III) and calcimedin 35 alpha. Antibodies to PAP III detected PAP III and inositol 1,2-cyclic phosphate 2-phosphohydrolase with identical reactivity on immunoblotting. In addition, inositol 1,2-cyclic phosphate 2-phosphohydrolase was stimulated by the same acidic phospholipids that bind lipocortins.


Asunto(s)
Proteínas de Unión al Calcio/genética , Hidrolasas Diéster Fosfóricas/genética , Placenta/enzimología , Secuencia de Aminoácidos , Anexina A3 , Anexinas , Femenino , Humanos , Immunoblotting , Cinética , Datos de Secuencia Molecular , Hidrolasas Diéster Fosfóricas/aislamiento & purificación , Hidrolasas Diéster Fosfóricas/metabolismo , Embarazo
7.
Science ; 225(4665): 923-5, 1984 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-17779865

RESUMEN

Materials representing common interstratified clay minerals are shown to be composed of aggregates of fundamental particles. Transmission electron microscopy and x-ray diffraction demonstrate that the x-ray diffraction characteristics of a wide range of interstratification can be modeled experimentally by utilizing materials containing only three types of particles. The data have been incorporated into a new model that regards interstratified clay minerals as populations of fundamental particles whose x-ray diffraction patterns result from interparticle diffraction.

8.
Ultrasound Obstet Gynecol ; 33(4): 407-11, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19306472

RESUMEN

OBJECTIVES: To examine the use of oblique planes from stored three-dimensional (3D) ultrasound volumes of the fetal face for viewing the secondary palate at various gestational ages. METHODS: 3D ultrasound volumes of the fetal face acquired with surface rendering at 15-35 weeks' gestation in 31 fetuses with confirmed normal secondary palates were reviewed. The secondary palate was viewed in three oblique planes targeted at the uvula: the oblique axial, the oblique sagittal and the reverse face view. The detection and appearance of the secondary palate, including the soft palate, with these views at various gestational ages were compared. RESULTS: The various surfaces of the secondary palate could be viewed in all 31 fetuses in the oblique axial and the reverse face views, and in all except two fetuses in the oblique sagittal view. Both of these were < 19 weeks' gestation, at which age the uvula could not be identified clearly in this plane. CONCLUSIONS: The oblique axial, the oblique sagittal and the reverse face view targeted at the uvula allow visualization of the various aspects of the fetal secondary palate on 3D ultrasound in the second and third trimesters of pregnancy. The uvula could be used as a landmark for viewing the soft palate, but was not always easily identifiable before 19 weeks' gestation.


Asunto(s)
Labio Leporino/diagnóstico por imagen , Fisura del Paladar/diagnóstico por imagen , Cara/diagnóstico por imagen , Enfermedades Fetales/diagnóstico por imagen , Hueso Paladar/diagnóstico por imagen , Cara/embriología , Edad Gestacional , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Imagenología Tridimensional/métodos , Hueso Paladar/embriología , Ultrasonografía Prenatal/métodos , Úvula/diagnóstico por imagen , Úvula/embriología
9.
Ultrasound Obstet Gynecol ; 33(6): 634-7, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19291694

RESUMEN

OBJECTIVES: To describe the sonographic appearance of the decidua basalis and its changes in the first trimester of pregnancy. METHODS: We reviewed images from 159 first-trimester ultrasound examinations in 105 women with uncomplicated pregnancies who later delivered at term. The appearance of the decidua basalis layer and the sonographic changes that it underwent, including in echogenicity and thickness, were analyzed with respect to gestational age. RESULTS: A distinct decidual layer could be identified consistently at 5-6 weeks' gestation and its thickness peaked at 6-7 weeks. It was seen inconsistently at 8-9 weeks and was not identifiable by 10 weeks. Its appearance changed over time, from a uniformly echogenic layer at 5-6 weeks to a heterogeneous echogenic layer at 7 weeks, corresponding to the histological evidence of trophoblast penetration. The layer then became less echogenic with time until it became unidentifiable. CONCLUSIONS: There is a window of opportunity in the first trimester for sonographic examination of the decidua. This may allow screening, at an early stage, for conditions that affect the decidua during pregnancy.


Asunto(s)
Decidua/diagnóstico por imagen , Trofoblastos/diagnóstico por imagen , Adolescente , Adulto , Decidua/fisiología , Femenino , Edad Gestacional , Humanos , Embarazo , Primer Trimestre del Embarazo , Trofoblastos/fisiología , Ultrasonografía Prenatal , Adulto Joven
10.
Fetal Diagn Ther ; 25(1): 31-5, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19153494

RESUMEN

OBJECTIVE: To present and discuss the sonographic and clinical findings in one twin of a monochorionic pair affected by amyoplasia. METHODS: On ultrasound examination at 21 weeks in a monochorionic twin pregnancy, twin I was smaller, hydropic, with multiple contractures consistent with amyoplasia and oligohydramnios. Twin II was anatomically normal with polyhydramnios. RESULTS: The twins were delivered at 28 weeks' gestation. The clinical findings were consistent with twin-twin transfusion syndrome (TTTS). CONCLUSION: It is postulated that TTTS may be a causative factor in the excessive incidence of amyoplasia in monozygotic twin pregnancy.


Asunto(s)
Artrogriposis/diagnóstico por imagen , Transfusión Feto-Fetal/diagnóstico por imagen , Gemelos , Adulto , Artrogriposis/etiología , Femenino , Transfusión Feto-Fetal/complicaciones , Humanos , Embarazo , Embarazo Múltiple , Ultrasonografía
11.
Vaccine ; 37(5): 690-692, 2019 01 29.
Artículo en Inglés | MEDLINE | ID: mdl-30392767

RESUMEN

Human papillomavirus (HPV) vaccines are currently utilised globally in national immunisation programmes. Many new European migrants have settled in the United Kingdom (UK) since the 2004 European Union expansion with approximately 91,000 Polish people resident in Scotland. Following anecdotal reports from several NHS Boards within Scotland of lower HPV vaccine uptake in Polish communities compared with other ethnic minorities, an extract containing both forename and surname, was taken from the Scottish Immunisation Recall System (SIRS) for all girls in S2 and S3 in school years 2014/15 to 2016/17. We then used the OnoMap algorithm software to derive ethnicity. OnoMap identified between 289 and 321 age-eligible girls as Polish with significant disparity noted for completed HPV vaccine uptake between UK (87.2-89.8%) and Polish ethnicities (69.7-77.2%) (P < 0.01). Preliminary discussions with Polish families suggest that vaccine programme differences, trust in medical/healthcare practitioners, and cultural influences may be important drivers of acceptance.


Asunto(s)
Infecciones por Papillomavirus/prevención & control , Vacunas contra Papillomavirus/administración & dosificación , Aceptación de la Atención de Salud/etnología , Migrantes/psicología , Neoplasias del Cuello Uterino/prevención & control , Vacunación/psicología , Adolescente , Estudios de Cohortes , Femenino , Humanos , Aceptación de la Atención de Salud/psicología , Polonia/etnología , Escocia , Programas Informáticos
12.
Ultrasound Obstet Gynecol ; 32(1): 103-5, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18570241

RESUMEN

The prenatal diagnosis of anophthalmia can be made on the demonstration of absent eye globe and lens on the affected side(s) on two-dimensional ultrasound examination, but when the fetal head position is unfavorable three-dimensional (3D) ultrasound may reveal additional diagnostic sonographic features, including sunken eyelids and small or hypoplastic orbit on the affected side(s). We present two cases of isolated anophthalmia diagnosed on prenatal ultrasound examination in which 3D ultrasound provided additional diagnostic information. The reverse face view provides valuable information about the orbits and the eyeballs for prenatal diagnosis and assessment of anophthalmia.


Asunto(s)
Anoftalmos/diagnóstico por imagen , Cara/diagnóstico por imagen , Enfermedades Fetales/diagnóstico por imagen , Imagenología Tridimensional/métodos , Ultrasonografía Prenatal/métodos , Adulto , Femenino , Humanos , Embarazo , Segundo Trimestre del Embarazo , Tercer Trimestre del Embarazo
13.
Euro Surveill ; 13(44): pii: 19021, 2008 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-19000560

RESUMEN

This paper reflects on the qualitative risk analysis framework developed for a Foresight study on the Detection and Identification of Infectious Diseases, which was coordinated in 2005 by the United Kingdom (UK) under what is now the Government Office for Science, Department for Innovation, Universities and Skills. The risk assessment covered human, plant and animal diseases in the UK and Africa in the years 2015 and 2030. Through engaging a diverse pool of experts, we developed a model conceptualising disease spread as the outcome of interactions among sources, pathways and drivers. We then used this model to conduct a Delphi survey of experts. The factors perceived most likely to contribute to infectious disease spread in 2015 and 2030 included geographic extension of existing pathogens (partially due to climate change), over-use of antibiotics/antivirals/pesticides leading to drug resistance, and zoonoses. Our methodology provides a framework for those who need to integrate a wide range of perspectives and factors into their planning and analyses.


Asunto(s)
Control de Enfermedades Transmisibles/organización & administración , Enfermedades Transmisibles/epidemiología , Brotes de Enfermedades/prevención & control , Brotes de Enfermedades/estadística & datos numéricos , Transmisión de Enfermedad Infecciosa/prevención & control , Programas de Gobierno/organización & administración , Vigilancia de la Población/métodos , Medición de Riesgo/métodos , Control de Enfermedades Transmisibles/métodos , Humanos , Incidencia , Factores de Riesgo , Reino Unido/epidemiología
14.
Fetal Diagn Ther ; 24(2): 146-54, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18648216

RESUMEN

OBJECTIVES: To report a technique to view the fetal soft and hard palates, utilizing acquired routine 3-D volumes of the fetal face. METHOD: The axial, sagittal and coronal planes in acquired volumes of 3-D surface rendering of 5 normal fetal faces obtained at 19, 21, 23, 26 and 28 weeks, respectively, were reviewed by focusing on the uvula. RESULTS: The surfaces of the soft and the hard palate could be viewed in oblique axial, oblique sagittal and targeted coronal planes in all fetuses. CONCLUSION: Rotating or tilting of the axial, sagittal and coronal planes of the fetal head allows the visualization of the various aspects of the soft and hard palates, with the uvula as a useful landmark.


Asunto(s)
Labio Leporino/diagnóstico por imagen , Fisura del Paladar/diagnóstico por imagen , Interpretación de Imagen Asistida por Computador , Imagenología Tridimensional , Paladar Duro/diagnóstico por imagen , Paladar Blando/diagnóstico por imagen , Ultrasonografía Prenatal , Labio Leporino/embriología , Fisura del Paladar/embriología , Estudios de Factibilidad , Edad Gestacional , Humanos , Paladar Duro/embriología , Paladar Blando/embriología , Estudios Retrospectivos , Úvula/diagnóstico por imagen
15.
Fetal Diagn Ther ; 24(1): 71-3, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18504386

RESUMEN

OBJECTIVE: To present the early 2D and 3D ultrasound findings and the molecular confirmation in a case of thanatophoric dysplasia. METHODS: On ultrasound examination, there was frontal bossing, increased nuchal translucency and short limbs at 12 weeks' gestation and a small thorax and short and bowed long bones on 3D at 16 weeks. Amniocentesis and DNA analysis confirmed the mutation of FGFR3 gene indicating thanatophoric dysplasia. RESULTS: After medical termination of pregnancy, the postmortem X-ray and pathology examination findings were consistent with the diagnosis. CONCLUSION: 3D anatomy scan and molecular confirmation may be helpful in early diagnosis and genetic counseling of thanatophoric dysplasia.


Asunto(s)
Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos/genética , Displasia Tanatofórica/diagnóstico por imagen , Ultrasonografía Prenatal , Adulto , Femenino , Humanos , Imagenología Tridimensional , Mutación , Embarazo , Displasia Tanatofórica/genética , Displasia Tanatofórica/patología , Ultrasonografía Prenatal/métodos
16.
J Environ Radioact ; 99(6): 933-46, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18180083

RESUMEN

A literature review and field sampling were done to obtain information on primordial (natural-series) radionuclide concentrations in terrestrial environments in diverse locations across Canada. Of special interest was the degree of secular equilibrium among members of decay series. The analytes measured in soils and plants were (nat)U by neutron activation-delayed neutron counting, (228)Th, (230)Th, (232)Th, (226)Ra and (210)Po by alpha spectroscopy, (210)Pb by gas flow proportional counting, (228)Ra by beta counting and (137)Cs by gamma spectroscopy. In addition, ICP-MS was used to obtain concentrations of about 50 analytes including elemental U, Pb, and Th. Samples were from seven representative background sites with a total of 162 plant samples from 38 different species. These data were supplemented by a review that gathered a large portion of the similar data from published sources. The sites chosen were semi-natural, far from any nuclear industry, although several were specifically located in areas with slightly elevated natural U concentrations. As might be expected, there were many cases of non-detectable concentrations. However, certain trends were evident. The activity ratio (210)Po/(210)Pb was unity in soils and non-annual plant tissues such as lichens. It was about 0.6 in annual plant tissues. These results are consistent with the time required for ingrowth of (210)Po to reach secular equilibrium. There was evidence from several sources that (210)Pb in plants came predominantly from deposition of (210)Pb from air after the decay of airborne (222)Rn. This was expected. Somewhat unexpected was the observation that (228)Th seemed to be much more plant available than (232)Th, even though both are in the same decay series and should be chemically similar. The difference was attributed to the combined effects of ingrowth from (228)Ra in the plant and effects of alpha recoil in mobilizing (228)Th in the soil. In general, the results of this study will benefit risk assessment, both in providing background concentrations, but also some indication of where isotope activity ratios can and cannot be used to estimate concentrations.


Asunto(s)
Monitoreo de Radiación/métodos , Radioisótopos/análisis , Canadá , Radioisótopos de Cesio/análisis , Polonio/análisis , Radio (Elemento)/análisis , Torio/análisis
17.
J Clin Invest ; 47(11): 2423-9, 1969 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-5775341

RESUMEN

Aldosterone metabolism has been shown to be altered in pregnancy. The increased conversion of intravenously administered aldosterone-(3)H to the acid-labile conjugate in the urine (aldosterone 18-glucuronide) has again been observed. The urinary yield of intravenously administered aldosterone-(3)H as aldosterone 18-glucuronide in 16 pregnant subjects of 13.4+/-0.9 (SE)% was significantly higher (P 0.001) than in 11 nonpregnant subjects (seven males and four females) of 7.3+/-0.5 (SE)%. After combining oral ((14)C) and intravenous ((3)H) administration of aldosterone, the (14)C/(3)H ratios of urinary metabolites (free aldosterone, tetrahydroaldosterone glucuronide, and aldosterone 18-glucuronide) were measured and were expressed as a per cent of administered dose. From these data the splanchnic extraction of aldosterone was calculated. The splanchnic extraction was significantly lower in pregnant as compared to nonpregnant subjects, although previous work indicated no change in protein binding of aldosterone in pregnancy.However, the data on the (14)C/(3)H ratio of other metabolites suggested that a large part of the increased aldosterone 18-glucuronide metabolite in pregnancy is formed in the splanchnic circulation; also, there appeared to be increased tetrahydroaldosterone glucuronide formation extrasplanchnically.


Asunto(s)
Aldosterona/metabolismo , Embarazo , Adulto , Aldosterona/administración & dosificación , Aldosterona/sangre , Aldosterona/farmacología , Aldosterona/orina , Presión Sanguínea , Isótopos de Carbono , Estrógenos/orina , Femenino , Glucuronatos/orina , Humanos , Inyecciones Intravenosas , Masculino , Tritio
18.
J Clin Invest ; 47(1): 93-106, 1968 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16695949

RESUMEN

The continuous infusion of (3)H-6,7-estrone and (3)H-6,7-estradiol has been used to study the metabolic clearance rate (MCR), the interconversions, and the red cell uptake of these steroids in normal males and females. The whole blood MCR of estrone is 1,990 +/- 120 liters per day/m(2) (SE) in males and 1,910 +/- 100 liters per day/m(2) in females. The whole blood MCR of estradiol is 1,600 +/- 80 liters per day/m(2) in males and 1,360 +/- 40 liters per day/m(2) in females. The values in females do not vary significantly when studied in the follicular or luteal phase of the cycle. At least 35% of the total estrone metabolism in both sexes is extrasplanchnic and at least 25% of the total estradiol metabolism in males, and 15% in females is extrasplanchnic. The [rho](BB) (2,1) [transfer constant of estradiol to estrone, which is equivalent to the fraction of the precursor (estradiol) converted to the product (estrone) when both the infusion of the precursor and the measurement of the product are in peripheral blood] is 15%; and the [rho](BB) (1,2) [transfer constant of estrone to estradiol, which is equivalent to the fraction of the precursor (estrone) converted to product (estradiol) when both the infusion of the precusor and the measurement of the product are in peripheral blood] is 5% in both males and females. Our findings concerning the radioactivity in whole blood, as measured by our procedure, were the following: 15-20% of estrone in both sexes and 15% of estradiol in males is associated with red cells. Only 2% of the whole blood radioactivity of estradiol in females is associated with red cells. Changes in the distribution of radioactivity between plasma and red cells will influence the MCR as calculated from plasma, but not as calculated from whole blood.

19.
J Clin Invest ; 46(5): 717-27, 1967 May.
Artículo en Inglés | MEDLINE | ID: mdl-6025478

RESUMEN

After intravenous and oral administration of radioactive aldosterone to normal subjects, 7.3 +/- 0.4 (SE) and 5.4 +/- 0.5 (SE)%, respectively, of the dose was recovered from a 48-hour collection of urine as aldosterone released by mild acid hydrolysis (from aldosterone 18-glucuronide), and 35 +/- 5 (SE) and 39 +/- 4 (SE)%, respectively, was recovered as tetrahydroaldosterone after incubation with beta-glucuronidase.After intravenous and oral administration of 17-isoaldosterone-4-(14)C to a similar group of subjects, 35 +/- 3 (SE) and 53 +/- 4 (SE)%, respectively, of the dose was recovered as 17-isoaldosterone released by acid and less than 5% as total metabolites after incubation with beta-glucuronidase. No detectable radioactivity (< 0.5%) could be recovered as tetrahydroaldosterone or as a compound with the expected chromatographic properties of tetrahydro-17-isoaldosterone. The total radioactivity in the neutral extracts was also relatively small (< 2%) after administration of either labeled aldosterone or 17-isoaldosterone. The radioactivity as aldosterone in the neutral extract was much lower after oral [0.017 +/- 0.003 (SE)%] than after intravenous [0.21 +/- 0.04 (SE)%] administration of labeled aldosterone. The radioactivity as 17-isoaldosterone in the neutral extract was similar after intravenous [0.20 +/- 0.02 (SE)%] and after oral [0.38 +/- 0.18 (SE)%] administration of 17-isoaldosterone. These results indicated that, due to lack of A-ring reduction of the molecule and the consequent slowing of hepatic clearance, 17-isoaldosterone is converted to an acid-labile conjugate (presumably 17-isoaldosterone 18-glucuronide) as the major metabolite. 17-Isoaldosterone was not secreted or converted to aldosterone to any significant extent in the normal subjects investigated.


Asunto(s)
Aldosterona/metabolismo , Isótopos de Carbono , Glucuronidasa , Humanos
20.
J Clin Invest ; 46(6): 960-6, 1967 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6026101

RESUMEN

The secretion rates [34 +/- 6 (SE) mug per day, 9 subjects] and metabolic clearance rates (MCR) [1,288 +/- 120 (SE) L of plasma per day, 9 subjects] of aldosterone in elderly subjects are significantly lower than those of young subjects [77 +/- 7 (SE) mug per day and 1,631 +/- 106 (SE) L per day, respectively]. There is a correlation of the MCR and secretion rate values (p = 0.02), but the calculated plasma concentrations (secretion rate/MCR) are also significantly low in the elderly subjects [2.6 +/- 0.3 (SE) compared with concentrations in the plasma from young subjects of 4.7 +/- 0.6 (SE) mug per 100 ml plasma]. The urinary excretion of radioactivity from oral and intravenously administered labeled aldosterone as aldosterone in the neutral extract, as aldosterone released by acid hydrolysis, and as tetrahydroaldosterone released by incubation with beta-glucuronidase is generally similar for young and elderly subjects except that a larger portion of the oral compared with the intravenous dose is excreted as free aldosterone in the elderly subjects, indicating that the splanchnic extraction is reduced. The calculated splanchnic blood flow (assuming no alteration in extrasplanchnic metabolism) is also slightly lowered. Therefore, as in patients with mild cardiac dysfunction, the lowered MCR of subjects is due to both reduced splanchnic extraction and blood flow. However, unlike the heart failure patients, in the elderly subjects the plasma concentration of aldosterone is also reduced.


Asunto(s)
Anciano , Aldosterona/metabolismo , Aldosterona/fisiología , Adolescente , Adulto , Aldosterona/sangre , Aldosterona/orina , Velocidad del Flujo Sanguíneo , Humanos , Inyecciones Intravenosas , Masculino , Tasa de Secreción
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