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Dive into the research topics where Laurence Brown is active.

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Featured researches published by Laurence Brown.


web science | 2000

Endometrial protection from tamoxifen-stimulated changes by a levonorgestrel-releasing intrauterine system: a randomised controlled trial

F. J. E. Gardner; Justin C. Konje; Keith R. Abrams; Laurence Brown; S. Khanna; F. Al-Azzawi; Stephen C. Bell; David J. Taylor

INTRODUCTION Tamoxifen is currently the most commonly used adjuvant treatment for breast cancer, however, it frequently causes episodes of unscheduled uterine bleeding, which could be associated with proliferative changes of the endometrium, or even endometrial cancer. We aimed to assess whether a levonorgestrel intrauterine system could modulate the uterine responses to tamoxifen. We also aimed to assess womens tolerance of the screening procedures, the insertion, removal, and potential side-effects of the device. METHODS We did a randomised controlled trial, in which postmenopausal women who had had at least 1 year of adjuvant tamoxifen treatment and who were undergoing regular follow-up for breast cancer were randomly assigned to either endometrial surveillance alone, or endometrial surveillance before and after insertion of the levonorgestrel intrauterine system for 12 months. We assessed tolerance of the surveillance procedures and the device with visual analogue scales. FINDINGS Baseline assessment showed only benign uterine changes in all women (n=122). Hysteroscopic assessment indicated a uniform decidual response (confirmed histologically in 40 of 41 cases) in all women fitted with the intrauterine system; there were no new polyps in these women and 13% had fewer fibroids than in controls. Both screening procedures and device were well tolerated. There was an excess of bleeding in the women fitted with intrauterine systems but this resolved to a baseline similar to those receiving surveillance only. INTERPRETATION The levonorgestrel-releasing intrauterine system had a protective action against the uterine effects of tamoxifen. The effectiveness of this device in preventing uterine changes in the endometrium needs to be assessed in the context of decreasing the need for repeated investigations of postmenopausal bleeding in women taking tamoxifen.


PLOS ONE | 2009

Localisation and function of the endocannabinoid system in the human ovary.

Mona R. El-Talatini; Anthony H. Taylor; Janine Elson; Laurence Brown; Allan C. Davidson; Justin C. Konje

Background Although anandamide (AEA) had been measured in human follicular fluid and is suggested to play a role in ovarian follicle and oocyte maturity, its exact source and role in the human ovary remains unclear. Methods and Findings Immunohistochemical examination of normal human ovaries indicated that the endocannabinoid system was present and widely expressed in the ovarian medulla and cortex with more intense cannabinoid receptor 2 (CB2) than CB1 immunoreactivity in the granulosa cells of primordial, primary, secondary, tertiary follicles, corpus luteum and corpus albicans. The enzymes, fatty acid amide hydrolase (FAAH) and N-acyclphosphatidylethanolamine-phospholipase D (NAPE-PLD), were only found in growing secondary and tertiary follicles and corpora lutea and albicantes. The follicular fluid (FF) AEA concentrations of 260 FF samples, taken from 37 infertile women undergoing controlled ovarian hyperstimulation for in vitro fertilisation and intracytoplasmic sperm injection with embryo transfer, were correlated with ovarian follicle size (P = 0.03). Significantly higher FF AEA concentrations were also observed in mature follicles (1.43±0.04 nM; mean±SEM) compared to immature follicles (1.26±0.06 nM), P = 0.0142 and from follicles containing morphologically assessed mature oocytes (1.56±0.11 nM) compared to that containing immature oocytes (0.99±0.09 nM), P = 0.0011. ROC analysis indicated that a FF AEA level of 1.09 nM could discriminate between mature and immature oocytes with 72.2% sensitivity and 77.14% specificity, whilst plasma AEA levels and FF AEA levels on oocyte retrieval day were not significantly different (P = 0.23). Conclusions These data suggest that AEA is produced in the ovary, is under hormonal control and plays a role in folliculogenesis, preovulatory follicle maturation, oocyte maturity and ovulation.


Fertility and Sterility | 2011

Estrogen and progesterone receptor isoform distribution through the menstrual cycle in uteri with and without adenomyosis.

Mohamed Khairy Mehasseb; Rina Panchal; Anthony H. Taylor; Laurence Brown; Stephen C. Bell; Marwan Habiba

OBJECTIVE To test the hypothesis that the expression of the different isoforms of the estrogen receptor alpha (ER-α) and beta (ER-β) and the progesterone receptor A (PR-A) and B (PR-B) would be differentially modulated in uteri with adenomyosis compared with controls and that modulation would be related to the menstrual cycle. DESIGN Case control, blinded comparison. SETTING University department. PATIENT(S) 54 premenopausal women with and 35 without uterine adenomyosis as the sole pathology. INTERVENTION(S) Multiple samples studied using immunohistochemistry for estrogen and progesterone receptors. MAIN OUTCOME MEASURE(S) Histomorphometric analysis of receptor expression. RESULT(S) The ER-α expression in the adenomyotic endometrium was different from that of the normal endometrium and the foci in the midsecretory phase of the cycle, but expression of ER-α in the inner and outer myometrium was not statistically significantly different. The ER-β expression was statistically significantly elevated in the adenomyotic functionalis gland during the proliferative phase and throughout the myometrium across the entire menstrual cycle. Expression of PR-A was similar to that of PR-B, with reduced expression in the basalis stroma, and inner and outer myometrium in the adenomyotic samples. The pattern of ER-β, PR-A, and PR-B expression was similar in the endometrial basalis and adenomyotic foci. CONCLUSION(S) These data suggest ER-β expression and the lack of PR expression are related to the development and/or progression of adenomyosis and might explain the poor response of adenomyosis-associated menstrual symptoms to progestational agents.


Gynecologic Oncology | 2009

Prevention of tamoxifen induced endometrial polyps using a levonorgestrel releasing intrauterine system long-term follow-up of a randomised control trial.

Francis J.E. Gardner; Justin C. Konje; Stephen C. Bell; Keith R. Abrams; Laurence Brown; David J. Taylor; Marwan Habiba

OBJECTIVES In a RCT, we have previously shown that the levonorgestrel intrauterine system (LNG-IUS, Mirena) produces a decidual response protecting the endometrium at one year follow-up. We here report on the long-term follow-up of this group of women, to test the hypothesis that a LNG-IUS could prevent the pro-proliferative uterine responses of tamoxifen for up to 4.5 years. METHODS A randomised-controlled trial of postmenopausal women who had taken at least one year of adjuvant tamoxifen therapy. RESULTS One hundred twenty-two women were recruited. Nine were found to be ineligible after randomisation. The average duration of follow-up was 26.25 months (IQR 14.5-36 months) in the surveillance group and 24.2 months (IQR 13.75-32.5 months) in the LNG-IUS group. Women with LNG-IUS in situ at the time of final assessment had decidualised endometrium, and no polyps. In the surveillance group new polyps arose in 8 cases. There were 3 new polyps in the group initially randomised to LNG-IUS, one in a patient who did not have the device inserted and 2 occurred in patients following the removal of the LNG-IUS. Univariate Cox proportional hazards regression models identified only endometrial thickness at trial entry as a statistically significant variable (HR 1.12, 95% CI 1.02 to 1.22, p=0.01) for the development of polyps. CONCLUSION This study confirms that LNG-IUS induces benign endometrial changes and prevents endometrial polyps but only during its use in women taking tamoxifen. Endometrial thickness is a risk factor for the development of polyps.


Orbit | 2008

Lacrimal Fossa Lesions: Pictorial Review of CT and MRI Features

Ram Vaidhyanath; R. Kirke; Laurence Brown; Raghavan Sampath

A wide range of disease process involve the lacrimal gland/fossa. In this pictorial review, we use histology-proven cases to illustrate conditions that affect the lacrimal gland/fossa. CT and MRI features of neoplastic, inflammatory, infiltrative, and developmental conditions are discussed.


Ophthalmic Plastic and Reconstructive Surgery | 2004

Localized inferior orbital fibrosis associated with porcine dermal collagen xenograft orbital floor implant.

David Cheung; Laurence Brown; Raghavan Sampath

We describe the clinical features, treatment, and histologic changes of a case of severe localized orbital inflammation associated with the use of porcine dermal collagen xenograft (Permacol) as an orbital floor implant in a 14-year-old boy. After uneventful blowout fracture repair with normal forced duction testing after insertion of a Permacol implant, progressive elevation and depression deficit developed in the postoperative period. There was no improvement after removal of the Permacol implant. Exploratory surgery revealed gross fibrosis of the inferior rectus muscle accounting for the abnormal ocular motility. Biopsy of the inferior rectus muscle showed chronic granulomatous inflammation suggestive of foreign body reaction. Although porcine dermal collagen xenograft has been suggested as an implant for orbital floor repair because of its reported high strength, ease of handling, and high biocompatibility, we believe that further studies are necessary before it can be recommended for this use.


Gynecologic and Obstetric Investigation | 2011

Phenotypic characterisation of the inner and outer myometrium in normal and adenomyotic uteri.

Mohamed Khairy Mehasseb; Stephen C. Bell; Laurence Brown; James Howard Pringle; Marwan Habiba

Background and Aim: To study the characteristics of the inner (IM) and outer (OM) myometrium in the presence and absence of uterine adenomyosis. Methods: Case control blinded comparison carried out in a university department. Morphometric features of the myometrium were studied in uteri from pre- and postmenopausal women with and without uterine adenomyosis as the sole pathology. Uteri were also divided according to the phase of the cycle and examined using immunohistochemistry and image analysis. Results: Cell density and total nuclear area were statistically significantly greater in the IM compared to OM, in pre- and postmenopausal women, in both the adenomyosis and control uteri. The difference in nuclear size was statistically significant only in the premenopausal group. The change from the IM to the OM in cell density and total nuclear area was gradual with no distinct zonation. Examined features did not vary with cycle phase. Both the IM and OM in adenomyosis exhibited lower cell density and larger nuclei compared to controls. In adenomyosis, immunostaining for α-smooth muscle actin, desmin and Ki-67 was consistent with myometrial hyperplasia and hypertrophy. Conclusions: There are clear differences between the IM and the OM but the transition is gradual, with no distinct zonation. Adenomyosis is characterised by reduced cell density, and increased nuclear size and features of hyperplasia and hypertrophy that are not confined to the IM.


The American Journal of Surgical Pathology | 2012

Clinical outcome of atypical endometrial hyperplasia diagnosed on an endometrial biopsy: institutional experience and review of literature.

Emad A. Rakha; Siew Chee Wong; Irshad Soomro; Zia Chaudry; Aarti Sharma; Suha Deen; Stephen Chan; Jafaru Abu; David Nunns; Karin Williamson; Angus McGregor; Robert Hammond; Laurence Brown

Abstract:The aims of this study were: (1) to review the rate of concurrent endometrial cancer in patients with a preoperative diagnosis of atypical endometrial hyperplasia (AEH); and (2) to determine the features of concurrent endometrial carcinoma and their impact on the subsequent management of AEH. We reviewed a retrospective series of 219 AEHs diagnosed locally in routine practice, over 24 years, and followed by a repeat biopsy or hysterectomy. Another series of 65 cases with a malignant diagnosis on preoperative sampling was included as a control group. Clinicopathologic parameters were obtained. In addition, published data on the risk of malignancy and features of malignant tumors after a diagnosis of AEH were collected and analyzed. This study reported on 2571 patients diagnosed in 31 published studies in addition to the current one. This showed a wide variation in the positive predictive value (PPV) of AEH in detecting endometrial cancer (6% to 63%) with an overall PPV of 37%. This variation is not only based on the differences among studies but also on the degree of atypia [mild/moderate (PPV 13%) or severe (PPV 50%)], the type of subsequent intervention (biopsy vs. hysterectomy), and more importantly the time period of diagnosis (around 20% in studies published before 1990s and up to 40% to 48% in recently published cases). Of the benign outcome cases, nearly 40% to 50% showed AEH with a potential risk of progressing to invasive carcinoma in 25% of cases. Malignant tumors after AEH diagnosis are associated with features of good prognosis with endometrioid morphology, lower grade, and early stage. Although the overall PPV of AEH is 37%, a figure of 40% to 48% is expected in the cases currently diagnosed in routine practice. Providing qualifying criteria for AEH will help identify its different associated risks and therefore should be included in routine pathology reports whenever possible. Unless there is a clinical contraindication, hysterectomy should be performed to treat concurrent carcinoma and to reduce the risk of subsequent carcinoma in nonmalignant cases with residual AEH.


The Lancet | 2017

Diagnostic accuracy of post-mortem CT with targeted coronary angiography versus autopsy for coroner-requested post-mortem investigations: a prospective, masked, comparison study

Guy N. Rutty; Bruno Morgan; Claire Robinson; Vimal Raj; Mini Pakkal; Jasmin Amoroso; Theresa Visser; Sarah Saunders; Mike Biggs; Frances Hollingbury; Angus McGregor; Kevin West; Cathy Richards; Laurence Brown; Rebecca Harrison; Roger Hew

Summary Background England and Wales have one of the highest frequencies of autopsy in the world. Implementation of post-mortem CT (PMCT), enhanced with targeted coronary angiography (PMCTA), in adults to avoid invasive autopsy would have cultural, religious, and potential economic benefits. We aimed to assess the diagnostic accuracy of PMCTA as a first-line technique in post-mortem investigations. Methods In this single-centre (Leicester, UK), prospective, controlled study, we selected cases of natural and non-suspicious unnatural death referred to Her Majestys (HM) Coroners. We excluded cases younger than 18 years, known to have had a transmittable disease, or who weighed more than 125 kg. Each case was assessed by PMCTA, followed by autopsy. Pathologists were masked to the PMCTA findings, unless a potential risk was shown. The primary endpoint was the accuracy of the cause of death diagnosis from PMCTA against a gold standard of autopsy findings, modified by PMCTA findings only if additional substantially incontrovertible findings were identified. Findings Between Jan 20, 2010, and Sept 13, 2012, we selected 241 cases, for which PMCTA was successful in 204 (85%). Seven cases were excluded from the analysis because of procedural unmasking or no autopsy data, as were 24 cases with a clear diagnosis of traumatic death before investigation; 210 cases were included. In 40 (19%) cases, predictable toxicology or histology testing accessible by PMCT informed the result. PMCTA provided a cause of death in 193 (92%) cases. A major discrepancy with the gold standard was noted in 12 (6%) cases identified by PMCTA, and in nine (5%) cases identified by autopsy (because of specific findings on PMCTA). The frequency of autopsy and PMCTA discrepancies were not significantly different (p=0·65 for major discrepancies and p=0·21 for minor discrepancies). Cause of death given by PMCTA did not overlook clinically significant trauma, occupational lung disease, or reportable disease, and did not significantly affect the overall population data for cause of death (p≥0·31). PMCTA was better at identifying trauma and haemorrhage (p=0·008), whereas autopsy was better at identifying pulmonary thromboembolism (p=0·004). Interpretation For most sudden natural adult deaths investigated by HM Coroners, PMCTA could be used to avoid invasive autopsy. The gold standard of post-mortem investigations should include both PMCT and invasive autopsy. Funding National Institute for Health Research.


Cancer | 1993

Absence of epstein—barr virus in carcinoma of the cervix

David A. Hilton; Laurence Brown; James H. Pringle; Hamalata Nandha

Background. Cervical epithelium is known to contain receptors for Epstein‐Barr virus (EBV) and is a recognized site of viral shedding. Recent cases of nasopharyngeal carcinoma have been associated with cervical carcinoma, leading to speculation of a possible etiologic link between EBV and cervical carcinoma.

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David Ireland

Leicester Royal Infirmary

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Mike Biggs

University of Leicester

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