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1.
Gynecol Oncol Rep ; 32: 100545, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32072005

RESUMEN

Obesity is the greatest risk factor for endometrial cancer. There is often a lack of recognition amongst patients about this risk. Evidence for weight-loss in the management of endometrial cancer is emerging. This was questionnaire-based study, that examined opinions and attitudes of patients with endometrial cancer and obesity towards obesity as a risk factor for cancer as well as examining their willingness to engage in weight loss interventions as an alternative treatment to endometrial cancer. This survey was conducted in a gynaeoncology out-patient department in Ireland. A total of 45/50 (90%) of questionnaires were completed. The majority of the patients questioned (86.7%; 39/45) agreed that obesity is a disease. Just over half of the cohort (53.3%; 24/45) believed that obesity can cause cancer. Over one-third, 39.9% (18/45) either disagreed or strongly disagreed that obesity is a risk factor for endometrial cancer while 35.5% (16/45) agreed or strongly agreed. Two-thirds (66.6%; 30/45) knew that the greatest amount of weight could be lost through metabolic surgery. Over three-quarters (82.1%; 37/45) of patients surveyed would be willing to engage in a combination of treatments in order to achieve weight-loss should it be proven to have a role in the management of endometrial cancer. This study demonstrates a need for patient education regarding the strong relationship between obesity and endometrial cancer risk. Patients are willing to consider weight loss interventions if they were proven to be as safe and effective as pelvic surgery in the management of endometrial cancer.

2.
Int J Surg ; 36 Suppl 1: S24-S30, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27565245

RESUMEN

BACKGROUND: Surgical trainees are expected to demonstrate academic achievement in order to obtain their certificate of completion of training (CCT). These standards are set by the Joint Committee on Surgical Training (JCST) and specialty advisory committees (SAC). The standards are not equivalent across all surgical specialties and recognise different achievements as evidence. They do not recognise changes in models of research and focus on outcomes rather than process. The Association of Surgeons in Training (ASiT) and National Research Collaborative (NRC) set out to develop progressive, consistent and flexible evidence set for academic requirements at CCT. METHODS: A modified-Delphi approach was used. An expert group consisting of representatives from the ASiT and the NRC undertook iterative review of a document proposing changes to requirements. This was circulated amongst wider stakeholders. After ten iterations, an open meeting was held to discuss these proposals. Voting on statements was performed using a 5-point Likert Scale. Each statement was voted on twice, with ≥80% of votes in agreement meaning the statement was approved. The results of this vote were used to propose core and optional academic requirements for CCT. RESULTS: Online discussion concluded after ten rounds. At the consensus meeting, statements were voted on by 25 delegates from across surgical specialties and training-grades. The group strongly favoured acquisition of 'Good Clinical Practice' training and research methodology training as CCT requirements. The group agreed that higher degrees, publications in any author position (including collaborative authorship), recruiting patients to a study or multicentre audit and presentation at a national or international meeting could be used as evidence for the purpose of CCT. The group agreed on two essential 'core' requirements (GCP and methodology training) and two of a menu of four 'additional' requirements (publication with any authorship position, presentation, recruitment of patients to a multicentre study and completion of a higher degree), which should be completed in order to attain CCT. CONCLUSION: This approach has engaged stakeholders to produce a progressive set of academic requirements for CCT, which are applicable across surgical specialties. Flexibility in requirements whilst retaining a high standard of evidence is desirable.


Asunto(s)
Certificación/normas , Educación de Postgrado en Medicina/normas , Especialidades Quirúrgicas/educación , Organizaciones de Beneficencia , Técnica Delphi , Humanos , Irlanda , Sociedades Médicas , Reino Unido
3.
Leukemia ; 30(9): 1824-31, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27168466

RESUMEN

Intrachromosomal amplification of chromosome 21 (iAMP21) identifies a high-risk subtype of acute lymphoblastic leukaemia (ALL), requiring intensive treatment to reduce their relapse risk. Improved understanding of the genomic landscape of iAMP21-ALL will ascertain whether these patients may benefit from targeted therapy. We performed whole-exome sequencing of eight iAMP21-ALL samples. The mutation rate was dramatically disparate between cases (average 24.9, range 5-51) and a large number of novel variants were identified, including frequent mutation of the RAS/MEK/ERK pathway. Targeted sequencing of a larger cohort revealed that 60% (25/42) of diagnostic iAMP21-ALL samples harboured 42 distinct RAS pathway mutations. High sequencing coverage demonstrated heterogeneity in the form of multiple RAS pathway mutations within the same sample and diverse variant allele frequencies (VAFs) (2-52%), similar to other subtypes of ALL. Constitutive RAS pathway activation was observed in iAMP21 samples that harboured mutations in the predominant clone (⩾35% VAF). Viable iAMP21 cells from primary xenografts showed reduced viability in response to the MEK1/2 inhibitor, selumetinib, in vitro. As clonal (⩾35% VAF) mutations were detected in 26% (11/42) of iAMP21-ALL, this evidence of response to RAS pathway inhibitors may offer the possibility to introduce targeted therapy to improve therapeutic efficacy in these high-risk patients.


Asunto(s)
Aberraciones Cromosómicas , Cromosomas Humanos Par 21 , Sistema de Señalización de MAP Quinasas/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Proteínas ras/metabolismo , Animales , Bencimidazoles/farmacología , Supervivencia Celular , Xenoinjertos , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Ratones , Tasa de Mutación , Análisis de Secuencia de ADN
4.
Int J Surg ; 23 Suppl 1: S1-4, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26525269

RESUMEN

The Association of Surgeons in Training (ASiT) is a professional body and registered charity working to promote excellence in surgical training for the benefit of junior doctors and patients alike. ASiT is in-dependent of the National Health Service (NHS), Surgical Royal Colleges, and specialty associations and represents trainees in all ten surgical specialties. ASiT was delighted to welcome a number of distinguished guests and speakers to Glasgow for #ASiT2015. The theme of 'The Future of Surgery' delved into challenges surgical training faces, exciting developments into using technology to help patients, a glance at the past with the development of the Glasgow Coma Score and whether mortality truly is the future of measured outcomes. More than £3500 of prizes was awarded by the incoming President, Miss. Rhiannon Harries to the highest scoring papers presented selected from over 1000 abstracts submitted.


Asunto(s)
Organizaciones de Beneficencia , Cirugía General/educación , Sociedades Médicas , Humanos , Escocia
6.
Leukemia ; 29(8): 1623-31, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25943180

RESUMEN

The B-cell receptor (BCR) and its immature form, the precursor-BCR (pre-BCR), have a central role in the control of B-cell development, which is dependent on a sequence of cell-fate decisions at specific antigen-independent checkpoints. Pre-BCR expression provides the first checkpoint, which controls differentiation of pre-B to immature B-cells in normal haemopoiesis. Pre-BCR signalling regulates and co-ordinates diverse processes within the pre-B cell, including clonal selection, proliferation and subsequent maturation. In B-cell precursor acute lymphoblastic leukaemia (BCP-ALL), B-cell development is arrested at this checkpoint. Moreover, malignant blasts avoid clonal extinction by hijacking pre-BCR signalling in favour of the development of BCP-ALL. Here, we discuss three mechanisms that occur in different subtypes of BCP-ALL: (i) blocking pre-BCR expression; (ii) activating pre-BCR-mediated pro-survival and pro-proliferative signalling, while inhibiting cell cycle arrest and maturation; and (iii) bypassing the pre-BCR checkpoint and activating pro-survival signalling through pre-BCR independent alternative mechanisms. A complete understanding of the BCP-ALL-specific signalling networks will highlight their application in BCP-ALL therapy.


Asunto(s)
Antineoplásicos/uso terapéutico , Terapia Molecular Dirigida , Receptores de Células Precursoras de Linfocitos B/antagonistas & inhibidores , Leucemia-Linfoma Linfoblástico de Células Precursoras/prevención & control , Animales , Humanos , Receptores de Células Precursoras de Linfocitos B/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo
7.
World J Surg ; 39(2): 303-13; discussion 314, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25315087

RESUMEN

AIMS: Mentoring has been used extensively in the business world to enhance performance and maximise potential. Despite this, there is currently a paucity of literature describing mentoring for surgical trainees. This study examined the current extent of mentoring and investigated future needs to support this. METHODS: An electronic, 47-item, self-administered questionnaire survey was distributed via national and regional surgical mailing lists and websites through the Association of Surgeons in Training and Specialty Associations in the UK and Republic of Ireland. RESULTS: Overall, 565 fully completed responses were received from trainees in all specialties, grades and training regions. A total of 48.7 % of respondents reported that they have a surgical mentor, with no significant gender difference (p = 0.65). Of respondents, 52.5 % considered their educational supervisor and 45.5 % their current consultant as mentors. Modal duration of mentoring relationships was 1-2 years (24.4 %). A total of 90.2 % of mentors were in the same specialty, 60.7 % in the same hospital, and 88.7 % in the same training region. Mentors covered clinical and professional matters (99.3 %) versus pastoral and non-clinical matters (41.1 %). Mentoring was commonly face to face or via email and not documented (64.7 %). Of the 51.3 % without a mentor, 89.7 % would like a clinical mentor and 51.0 % a pastoral mentor (p < 0.001). Priority mentoring areas included career progression (94.9 %), research (75.2 %), clinical skills (66.9 %) and clinical confidence (58.4 %). A total of 94.3 % would be willing to act as a peer mentor. Only 8.7 % had received mentoring training; 83 % wish to undertake this. CONCLUSIONS: Less than half of surgical trainees identified a mentor. The majority want mentoring on professional topics during their training and would additionally be willing to peer-mentor colleagues, although few have received training for this. Despite an identified need, there is currently no structure for organising this and little national provision for mentoring.


Asunto(s)
Mentores/estadística & datos numéricos , Procedimientos Quirúrgicos Operativos/educación , Adulto , Investigación Biomédica , Movilidad Laboral , Competencia Clínica , Femenino , Humanos , Masculino , Mentores/educación , Persona de Mediana Edad , Evaluación de Necesidades , Autoeficacia , Encuestas y Cuestionarios , Adulto Joven
8.
Int J Surg ; 12 Suppl 3: S5-8, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25174790

RESUMEN

Mentoring has been present within surgical training for many years, albeit in different forms. There is evidence that formal mentoring can improve patient outcomes and facilitate learning and personal growth in the mentee. The Association of Surgeons in Training (ASiT) is an independent educational charity working to promote excellence in surgical training. This document recommends the introduction of a structured mentoring programme, which is readily accessible to all surgical trainees. A review of the available evidence--including an ASiT-led survey of its membership--highlights the desire of surgical trainees to have a mentor, whilst the majority do not have access to one. There is also limited training for those in mentoring roles. In response, ASiT have implemented a pilot mentoring scheme, with surgical trainees acting both as mentors and mentees. Based on the existing literature, survey data and pilot experience, ASiT formalises in this document consensus recommendations for mentoring in surgical training.


Asunto(s)
Cirugía General/educación , Mentores , Organizaciones de Beneficencia , Humanos , Sociedades Médicas , Reino Unido
9.
Int J Surg ; 12 Suppl 3: S9-12, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25150022

RESUMEN

The Association of Surgeons in Training (ASiT) is a professional body and registered charity working to promote excellence in surgical training for the benefit of junior doctors and patients alike. ASiT is independent of the National Health Service (NHS), Surgical Royal Colleges, and specialty associations and represents trainees in all ten surgical specialties. ASiT was delighted to welcome all four surgical Royal College Presidents and over 650 delegates to Belfast for ASiT 2014. With a theme of Marginal Gains, the conference programme explored collaboration, simulation training and human factors, complimented by debates including the Shape of Training Review (ShOT), several focussed parallel sessions and ten subsidised pre-conference training courses. Almost £4000 was awarded by the incoming President, Mr Vimal Gokani, to delegates across more than 30 prizes for delegates who presented the highest scoring academic work from over 1200 submitted abstracts.


Asunto(s)
Organizaciones de Beneficencia , Cirugía General/educación , Sociedades Médicas , Humanos , Reino Unido
11.
Scand J Med Sci Sports ; 23(4): 468-77, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22093085

RESUMEN

The effect of rowing ergometer design upon power delivery and coordination patterns of the rowing stroke was analyzed for 14 elite rowers. Rowers were tested in three ergometer conditions: the fixed stretcher Concept2c ergometer, the Concept2c ergometer mounted on sliding rails, and the sliding stretcher RowPerfect ergometer. Ergometers were instrumented to measure the external force generated at the handle and the foot stretcher and a nine-segment inverse dynamics model used to calculate joint and overall power delivery. Peak power generation and absorption at the knee joint was significantly greater, and total power delivered to the ergometer delayed on the fixed stretcher ergometer when compared to the sliding stretcher ergometers. No differences were found in the mechanical energy delivered to the handle of the three ergometers; however, greater joint mechanical energy production of the lower limb reduced mechanical efficiency when rowing the Concept2c fixed ergometer. The fixed foot stretcher on the Concept2c fixed ergometer acts to increase the inertial forces that the rower must overcome at the catch, increasing the moment and power output at the knee, and affecting the coordination pattern during the recovery phase.


Asunto(s)
Diseño de Equipo , Ergometría/instrumentación , Articulación de la Cadera/fisiología , Articulación de la Rodilla/fisiología , Deportes/fisiología , Adulto , Fenómenos Biomecánicos/fisiología , Metabolismo Energético , Humanos , Masculino , Torso/fisiología , Adulto Joven
12.
Artículo en Inglés | MEDLINE | ID: mdl-21467143

RESUMEN

How chromatin folds into mitotic and interphase chromosomes has remained a difficult question for many years. We have used three generations of engineered chromosome regions as a means of visualizing specific chromosome regions in live cells and cells fixed under conditions that preserve large-scale chromatin structure. Our results confirm the existence of large-scale chromatin domains and fibers formed by the folding of 10-nm and 30-nm chromatin fibers into larger, spatially distinct domains. Transcription at levels within severalfold of the levels measured for endogenous loci occur within these large-scale chromatin structures on a condensed template linearly compacted several hundred fold to 1000-fold relative to B-form DNA. However, transcriptional induction is accompanied by a severalfold decondensation of this large-scale chromatin structure that propagates hundreds of kilobases beyond the induced gene. Examination of engineered chromosome regions in mouse embryonic stem cells (ESCs) and differentiated cells suggests a surprising degree of plasticity in this large-scale chromatin structure, allowing long-range DNA interactions within the context of large-scale chromatin fibers. Recapitulation of gene-specific differences in large-scale chromatin conformation and nuclear positioning using these engineered chromosome regions will facilitate identification of cis and trans determinants of interphase chromosome architecture.


Asunto(s)
Cromatina/química , Cromosomas de los Mamíferos/genética , Ingeniería Genética , Interfase , Células 3T3 , Animales , Cromatina/ultraestructura , Cromosomas de los Mamíferos/ultraestructura , Células Madre Embrionarias/citología , Células Madre Embrionarias/metabolismo , Genoma Humano/genética , Células HeLa , Humanos , Ratones , Modelos Biológicos , Conformación de Ácido Nucleico , Transcripción Genética , Activación Transcripcional/genética
13.
West Indian Med J ; 59(2): 177-81, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21275122

RESUMEN

OBJECTIVE: To document the pathologic features of breast cancer in Jamaica. METHODS: The pathology reports and slides of all patients diagnosed with breast cancer at the National Public Health Laboratory between January 1999 and December 2002 were reviewed. Patient age and gender side involved, number of tumours identified, tumour size, histologic type, histologic grade, degree of lymph node involvement and parish of origin of the specimens were documented. RESULTS: There were 772 patients, 762 females and 10 males; age range 21 to 96 (mean 57.9 +/- 15.9) years. There were 778 specimens (6 bilateral cases), the majority of whom originated from Kingston and St Andrew (34.7%). Manchester (22.9%), St Catherine (13.9%) and St Ann (7.3%) were the next most common sources. The left breast was involved in 50.5% of cases. Gross tumour was identified in 641 (82.4%) specimens, the number of tumours ranging from 1 - 6 (mean 1.1 +/- 0.6). The maximum gross tumour dimension ranged from 0.3 to 15 cm (mean 4.1 +/- 2.7 cm). Infiltrating duct carcinoma was the predominant histologic type (69.3 %); 13.3%, 49.5% and 37.2 % of all infiltrating tumours were well, moderately and poorly differentiated respectively. In-situ lesions (7.1% of tumours) were all of the ductal phenotype. Axillary lymph nodes were submitted in 296 (38.1%) cases; metastatic disease was identified in 224 (75.7%) of these. The total number of nodes submitted ranged from 1 - 34 (mean 10.8 +/- 6.7) with an average of 6.1 (+/- 5.8) being positive for metastases (range 1 - 29). CONCLUSIONS: The pathologic features of breast cancer documented in this series including average tumour size, histologic types and grade and the degree of lymph node involvement are consistent with patient presentation at relatively advanced stages of disease and highlight the urgent need for public health intervention including a national screening programme.


Asunto(s)
Neoplasias de la Mama Masculina/patología , Neoplasias de la Mama/patología , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama Masculina/epidemiología , Femenino , Humanos , Jamaica/epidemiología , Masculino , Persona de Mediana Edad , Adulto Joven
14.
Br J Pharmacol ; 154(7): 1465-73, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18536749

RESUMEN

BACKGROUND AND PURPOSE: Inhibition of cholesteryl ester transfer protein (CETP) with torcetrapib in humans increases plasma high density lipoprotein (HDL) cholesterol levels but is associated with increased blood pressure. In a phase 3 clinical study, evaluating the effects of torcetrapib in atherosclerosis, there was an excess of deaths and adverse cardiovascular events in patients taking torcetrapib. The studies reported herein sought to evaluate off-target effects of torcetrapib. EXPERIMENTAL APPROACH: Cardiovascular effects of the CETP inhibitors torcetrapib and anacetrapib were evaluated in animal models. KEY RESULTS: Torcetrapib evoked an acute increase in blood pressure in all species evaluated whereas no increase was observed with anacetrapib. The pressor effect of torcetrapib was not diminished in the presence of adrenoceptor, angiotensin II or endothelin receptor antagonists. Torcetrapib did not have a contractile effect on vascular smooth muscle suggesting its effects in vivo are via the release of a secondary mediator. Treatment with torcetrapib was associated with an increase in plasma levels of aldosterone and corticosterone and, in vitro, was shown to release aldosterone from adrenocortical cells. Increased adrenal steroid levels were not observed with anacetrapib. Inhibition of adrenal steroid synthesis did not inhibit the pressor response to torcetrapib whereas adrenalectomy prevented the ability of torcetrapib to increase blood pressure in rats. CONCLUSIONS AND IMPLICATIONS: Torcetrapib evoked an acute increase in blood pressure and an acute increase in plasma adrenal steroids. The acute pressor response to torcetrapib was not mediated by adrenal steroids but was dependent on intact adrenal glands.


Asunto(s)
Presión Sanguínea/efectos de los fármacos , Proteínas de Transferencia de Ésteres de Colesterol/antagonistas & inhibidores , Oxazolidinonas/toxicidad , Quinolinas/toxicidad , Corteza Suprarrenal/citología , Corteza Suprarrenal/efectos de los fármacos , Aldosterona/sangre , Animales , Anticolesterolemiantes/toxicidad , Corticosterona/sangre , Perros , Evaluación Preclínica de Medicamentos , Femenino , Macaca mulatta , Masculino , Ratones , Ratones Endogámicos C57BL , Modelos Animales , Músculo Liso Vascular/efectos de los fármacos , Músculo Liso Vascular/metabolismo , Ratas , Ratas Sprague-Dawley , Especificidad de la Especie
15.
S Afr Med J ; 96(9 Pt 2): 955-9, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17077924

RESUMEN

INTRODUCTION: Renal transplantation is the therapy of choice for children with end-stage renal failure. There are many challenges associated with a paediatric programme in a developing country where organs are limited. METHODS: A retrospective review was undertaken of 149 paediatric renal transplants performed between 1968 and 2006 with specific emphasis on transplants performed in the last 10 years. Survival of patients and grafts was analysed and specific problems related to drugs and infections were reviewed. RESULTS: On review of the total programme, 60% of the transplants have been performed in the last 10 years, with satisfactory overall patient and graft survival for the first 8 years post transplant. At this point, transfer to adult units with non-compliance becomes a significant problem. Rejection is less of a problem than previously but infection is now a bigger issue--specifically tuberculosis (TB), cytomegalovirus (CMV) and Epstein-Barr virus (EBV) infections with related complications. A wide variety of drugs are available for tailoring immunosuppression to minimise side-effects. CONCLUSION: It is possible to have a successful paediatric transplant programme in a developing country. However, to improve long-term outcomes certain issues need to be addressed, including reduction of nephrotoxic drugs and cardiovascular risk factors and providing successful adolescent to adult unit transition.


Asunto(s)
Fallo Renal Crónico/cirugía , Trasplante de Riñón , Evaluación de Programas y Proyectos de Salud/tendencias , Adolescente , Niño , Preescolar , Femenino , Estudios de Seguimiento , Supervivencia de Injerto , Humanos , Lactante , Recién Nacido , Masculino , Complicaciones Posoperatorias , Estudios Retrospectivos
16.
Soc Reprod Fertil Suppl ; 62: 85-97, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16866311

RESUMEN

A review of the remarkable production of steroids by the testes of the boar is presented, with the principal aims of highlighting the achievements of the Leydig cells and, at the same time, pointing to the considerable deficiencies in our understanding of its biological relevance. The onset of gonadal steroidogenesis at an early stage of sex differentiation and the pattern of pre- and postnatal secretion of steroids are outlined. This is followed by a list of steroids identified in extracts of the boar testis, with emphasis on those that can reasonably be assumed to be secretory products of the Leydig cells. For example, the high concentrations of 16-unsaturated C19 and sulphoconjugated compounds are noted. Next, an impressive list of steroids found in venous blood from the boar testis is given; among them are the 16-unsaturated steroids, the oestrogens and dehydroepiandrosterone, all mainly in the form of sulphates. However, the list also includes some less likely members, such as 11-OH and 19-OH androgens as well as 5alpha-reduced steroids. Lastly, the high concentrations of steroids reported in testicular lymph, especially sulphates, are mentioned. Although roles for testosterone are uncontested, and even for the pheromone-like C19 steroids, there is little that can be said with assurance about the other compounds listed. Some speculations are made on their possible contributions to the reproductive physiology of the boar. This is done to provoke interest and, perhaps, even action towards reaching a more complete understanding of the biological significance of the steroidogenic powers of porcine Leydig cells.


Asunto(s)
Hormonas/biosíntesis , Reproducción/fisiología , Porcinos/metabolismo , Testículo/metabolismo , Animales , Hormonas/metabolismo , Células Intersticiales del Testículo/metabolismo , Masculino
17.
J Mol Endocrinol ; 36(2): 301-11, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16595701

RESUMEN

Hydroxysteroid sulfotransferase (SULT2A1) is a key enzyme in the testicular and hepatic metabolism of 5alpha-androstenone, which is a major component of the off-odor and off-flavor in pork known as boar taint. The goals of this study were to determine the role of testicular and hepatic SULT2A1 activity on plasma 5alpha-androstenone sulfate levels, the accumulation of 5alpha-androstenone in adipose tissue, and to gain insight into the regulatory control of SULT2A1. Testicular SULT2A1 activity was negatively correlated (r = -0.57; P < 0.01) with 5alpha-androstenone concentrations in fat. The differences observed in SULT2A1 activity warranted investigation into potential genetic variation within porcine SULT2A1. The cDNA sequence of porcine Sult2A1 was determined to be > 82% homologous to the human, mouse, and rat Sult2A1 genes. A single nucleotide polymorphism was detected within the coding region of the Sult2A1 from individual testes and liver samples; however, this did not affect the amino acid sequence of the enzyme. Western blot analysis determined that animals with high concentrations of 5alpha-androstenone in fat and low SULT2A1 activity had corresponding low levels of SULT2A1 protein compared with animals with low levels of 5alpha-androstenone in fat. Real-time PCR analysis indicated that Sult2A1 mRNA was increased 2.8-fold in animals with high levels of the protein relative to animals with low levels of the protein. Furthermore, we demonstrated the positive role of the nuclear receptors constitutive androstane receptor and pregnane X receptor, as well as the possible role of farnesoid X receptor in the regulation of testicular SULT2A1 activity. Together, the results of this study suggest that differences in SULT2A1 expression can influence 5alpha-androstenone accumulation in fat.


Asunto(s)
Androstenos/sangre , Sulfotransferasas/metabolismo , Azufre/metabolismo , Tejido Adiposo/metabolismo , Secuencia de Aminoácidos , Androstenos/química , Animales , Secuencia de Bases , Células Cultivadas , Clonación Molecular , Secuencia Conservada , ADN Complementario/genética , Regulación Enzimológica de la Expresión Génica , Humanos , Ligandos , Hígado/enzimología , Masculino , Datos de Secuencia Molecular , Polimorfismo Genético/genética , ARN Mensajero/genética , Receptores Citoplasmáticos y Nucleares/metabolismo , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Sulfotransferasas/química , Sulfotransferasas/genética , Azufre/química , Porcinos , Testículo/enzimología
18.
Aliment Pharmacol Ther ; 23(5): 595-9, 2006 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-16480398

RESUMEN

BACKGROUND: The prevalence of Barrett's oesophagus in patients undergoing gastroscopy may be influenced by possible referral bias. AIM: To present the prevalence of Barrett's oesophagus from the the Canadian Adult Dyspepsia Empirical Therapy Prompt Endoscopy study and to explore potential risk factors for its presence. METHODS: Patients had not been on treatment for dyspepsia for 2-4 weeks prior to endoscopy, which was performed within 10 working days of presentation. RESULTS: Barrett's oesophagus was endoscopically suspected in 53 of 1040 cases (5%) and histologically confirmed by the presence of intestinal metaplasia in 25 (2.4%). The prevalence of biopsy-proven Barrett's oesophagus was 4% in patients with dominant reflux-like symptoms. Sixty-four percent with confirmed Barrett's oesophagus had dominant reflux-like symptoms compared with 37% without Barrett's oesophagus. Barrett's oesophagus was more common in patients >50 years of age; 68% of cases were males. The mean duration of symptoms was 10 years, yet 16% had symptoms of <1-year duration. Endoscopic reflux oesophagitis was present in 68% of confirmed Barrett's oesophagus patients. CONCLUSIONS: Barrett's oesophagus is confirmed on biopsy in about half of endoscopically suspected Barrett's oesophagus patients. Barrett's oesophagus is more common in males, in those with dominant reflux-like symptoms, and in patients with a longer symptom history.


Asunto(s)
Esófago de Barrett/epidemiología , Dispepsia/epidemiología , Anciano , Esófago de Barrett/complicaciones , Esófago de Barrett/diagnóstico , Canadá/epidemiología , Estudios de Cohortes , Dispepsia/diagnóstico , Dispepsia/etiología , Esofagitis Péptica/diagnóstico , Esofagitis Péptica/epidemiología , Esofagitis Péptica/etiología , Esofagoscopía/métodos , Femenino , Reflujo Gastroesofágico/diagnóstico , Reflujo Gastroesofágico/epidemiología , Reflujo Gastroesofágico/etiología , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/diagnóstico , Infecciones por Helicobacter/epidemiología , Helicobacter pylori/aislamiento & purificación , Hernia Hiatal/diagnóstico , Hernia Hiatal/epidemiología , Hernia Hiatal/etiología , Humanos , Masculino , Persona de Mediana Edad , Prevalencia
19.
J Steroid Biochem Mol Biol ; 96(2): 217-28, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15955694

RESUMEN

This study examined the involvement of sulphoconjugation in the biosynthesis of the 16-androstene steroids in Leydig cells of the mature boar, since the formation of steroid sulphoconjugates can reduce the levels of these steroids that accumulate in fatty tissue. Leydig cells were purified from testes of mature male pigs and incubated with pregnenolone, or various individual 16-androstene steroids for 10 min, 1, 4 and 8h. Sulphoconjugated steroids were recovered by solid-phase extraction followed by solvolysis. Profiles of unconjugated and sulphoconjugated steroids were analysed by HPLC. Steroids present in the sulphoconjugated fractions were purified, derivatised as O-methoxime/trimethylsilyl ethers (MO-TMS), and subsequently identified using gas chromatography-mass spectrometry (GC-MS). The principal metabolite produced from incubations with pregnenolone, androstadienol, androstadienone and 5alpha-androstenone was 3beta-androstenol. 16-Androstene steroids that were sulphoconjugated included 5alpha-androstenone, 3beta-androstenol and 3alpha-androstenol. Approximately 70% of the total amount of each 16-androstene steroid was in its sulphoconjugated form after incubations for 4h or more. The finding that sulphoconjugated 5alpha-androstenone was present in large amounts suggests that this steroid may be converted from a 3-keto to a 3-enol form which is subsequently sulphoconjugated. These findings emphasise the need to consider the impact of sulphoconjugation of the 16-androstene steroids and their role in contributing to boar taint.


Asunto(s)
Androstanos/metabolismo , Células Intersticiales del Testículo/metabolismo , Androstenos/metabolismo , Animales , Cromatografía Líquida de Alta Presión , Masculino , Ácidos Sulfúricos/metabolismo , Porcinos , Testículo/fisiología
20.
J Steroid Biochem Mol Biol ; 96(1): 79-87, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15896952

RESUMEN

The hepatic metabolism of the 16-androstene steroids was investigated using isolated porcine hepatocytes. This study demonstrated that the liver is capable of producing both phase I and phase II steroid metabolites from 16-androstene steroid precursors. 16-Androstene metabolites were recovered by solid-phase extraction and identified by gas chromatography-mass spectrometry (GC-MS). When 5alpha-androstenone was provided as a substrate, both 3beta- and 3alpha-androstenol were produced as well as a metabolite that showed evidence of hydroxylation. Incubations with the various 16-androstene steroids produced metabolic profiles which suggested that the major role of the liver is phase II conjugation. Sulfoconjugated 16-androstene steroids included androstadienol, 5alpha-androstenone, 3beta-, 3alpha-androstenol, and possibly the hydroxylated metabolite of 5alpha-androstenone. It was determined that hydroxysteroid sulfotransferase (HST) is the likely candidate for the sulfoconjugation of the 16-androstene steroids within the liver. Despite the capacity of the hepatocytes to sulfoconjugate the 16-androstene steroids, the principle metabolites produced from incubations with 5alpha-androstenone, 3beta-, and 3alpha-androstenol were glucuronide conjugates, accounting for approximately 68% of all phase II metabolism. These findings underline the importance of steroid conjugation and suggest that hepatic metabolism of the 16-androstene steroids may influence the levels of 5alpha-androstenone present in the circulation, and thus, capable of accumulating in fat.


Asunto(s)
Androstenos/metabolismo , Hepatocitos/metabolismo , Animales , Células Cultivadas , Cromatografía de Gases y Espectrometría de Masas , Cinética , Porcinos
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