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Dive into the research topics where Justin C. Konje is active.

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Featured researches published by Justin C. Konje.


Trends in Pharmacological Sciences | 2015

Endocannabinoid signaling at the periphery: 50 years after THC

Mauro Maccarrone; Itai Bab; Tamás Bíró; Guy A. Cabral; Sudhansu K. Dey; Vincenzo Di Marzo; Justin C. Konje; George Kunos; Raphael Mechoulam; Pál Pacher; Keith A. Sharkey; Andreas Zimmer

In 1964, the psychoactive ingredient of Cannabis sativa, Δ(9)-tetrahydrocannabinol (THC), was isolated. Nearly 30 years later the endogenous counterparts of THC, collectively termed endocannabinoids (eCBs), were discovered: N-arachidonoylethanolamine (anandamide) (AEA) in 1992 and 2-arachidonoylglycerol (2-AG) in 1995. Since then, considerable research has shed light on the impact of eCBs on human health and disease, identifying an ensemble of proteins that bind, synthesize, and degrade them and that together form the eCB system (ECS). eCBs control basic biological processes including cell choice between survival and death and progenitor/stem cell proliferation and differentiation. Unsurprisingly, in the past two decades eCBs have been recognized as key mediators of several aspects of human pathophysiology and thus have emerged to be among the most widespread and versatile signaling molecules ever discovered. Here some of the pioneers of this research field review the state of the art of critical eCB functions in peripheral organs. Our community effort is aimed at establishing consensus views on the relevance of the peripheral ECS for human health and disease pathogenesis, as well as highlighting emerging challenges and therapeutic hopes.


BMJ | 2008

Maternal caffeine intake during pregnancy and risk of fetal growth restriction: a large prospective observational study

Sinead Boylan; Janet E Cade; Vivien A. Dolby; Darren C. Greenwood; Awm Hay; Sfl Kirk; Susan Shires; Nigel Simpson; James D Thomas; Jenny Walker; Klm White; Christopher P. Wild; Neelam Potdar; Justin C. Konje; Nick Taub; Jim Charvill; Karen C. Chipps; Shabira Kassam; C. Ghandi; Cooke

Correction to Maternal caffeine intake during pregnancy and risk of fetal growth restriction: a large prospective observational study, dx.doi.org/10.1136/bmj.a2332 available on the LRA at http://hdl.handle.net/2381/16058


Epigenetics | 2012

Smoking induces differential miRNA expression in human spermatozoa: A potential transgenerational epigenetic concern?

Emma L. Marczylo; Akwasi A. Amoako; Justin C. Konje; Timothy W. Gant; Timothy H. Marczylo

Recent work has suggested that environmental chemicals, including those contained in cigarette smoke, can have adverse effects on the exposed individuals as well as their future progeny. The mechanisms underlying transmission of environmentally induced phenotypes through the germ line are not well understood. However, a predominant process appears to be the establishment of permanent heritable epigenetic alterations, and a number of studies have implicated microRNAs in such processes. Here, we show that cigarette smoke induces specific differences in the spermatozoal microRNA content of human smokers compared with non-smokers, and that these altered microRNAs appear to predominantly mediate pathways vital for healthy sperm and normal embryo development, particularly cell death and apoptosis. microRNA-mediated perturbation of such pathways may explain how harmful phenotypes can be induced in the progeny of smokers.


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.


British Journal of Obstetrics and Gynaecology | 2003

Longitudinal quantification of uterine artery blood volume flow changes during gestation in pregnancies complicated by intrauterine growth restriction

Justin C. Konje; Edmund S. Howarth; Peter Kaufmann; David J. Taylor

Objective To quantify and compare longitudinal uterine artery volume flow changes in appropriate for gestational age (AGA) pregnancies and those complicated by intrauterine growth restriction (IUGR).


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.


Analytical Biochemistry | 2008

Ultra performance liquid chromatography tandem mass spectrometry method for the measurement of anandamide in human plasma.

Patricia M.W. Lam; Timothy H. Marczylo; Mona R. El-Talatini; Mark Finney; Vijaianitha Nallendran; Anthony H. Taylor; Justin C. Konje

Anandamide (N-arachidonoylethanolamine, AEA) is an endocannabinoid present in human plasma that is associated with several physiological functions and disease states. Significant variability in AEA plasma concentrations has been reported between studies, because quantification of AEA is fraught with methodological difficulties. A rapid, highly sensitive, robust, specific, and highly reproducible ultra high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method is described here for the analysis of AEA in human plasma. This fully validated method using octa-deuterated AEA (AEA-d8) as an internal standard represents an improvement over previous analyses in terms of run time (4 min), limit of detection (0.055 fmol on column, 18.75 fmol/ml plasma), precision (relative standard deviations of 3.7, 3.9, and 4.8% for 1.66, 6.65, and 133 fmol on column), and accuracy (97.5-104.5%). AEA analysis was linear over the range 0.23 to 19 nM (1.66 to 133 fmol on column). To demonstrate the usefulness of this method for the measurement of AEA levels in clinical samples, plasma samples obtained from female volunteers at different stages of the menstrual cycle and pregnant women were assayed. Plasma AEA concentrations were significantly (P=0.0078) lower in the luteal phase of the menstrual cycle compared to the follicular phase. In pregnancy, the concentrations were lowest in the first and second trimesters with levels comparable to those observed in the luteal phase of the menstrual cycle and modestly increased in the third trimester. The highest plasma AEA levels were observed in women in active labour, and these were significantly (P=0.0147) higher than those observed in women at term but not in active labour. Postmenopausal women had AEA concentrations comparable to levels observed during the luteal phase of premenopausal women and were significantly (P=0.0389) lower than AEA plasma concentrations obtained during the follicular phase. The sensitivity and precision of the validated method described here suggests that this method is suitable for the analysis of AEA in clinical samples and may be utilised for the investigation of biomatrices containing limited amounts of AEA.


JAMA | 2008

Plasma anandamide concentration and pregnancy outcome in women with threatened miscarriage.

Osama M. H. Habayeb; Anthony H. Taylor; Mark Finney; Mark D. Evans; Justin C. Konje

motherapy for patients who have received treatment in the past. Our recommendation to treat patients with impending immunosuppression (from human immunodeficiency virus infection, induction for organ transplant, or other etiologies) who have not previously received antitrypanosomal therapy should be interpreted in the context of our overall BII recommendation for T cruzi–infected adults up to age 50 years without advanced heart disease. The major objective of etiologic treatment in this setting is to prevent development or progression of cardiomyopathy. Our intention in explicitly listing anticipated immunosuppressionasapatientcategoryfortreatmentwastolendadditional weight to the recommendation since we assume that antitrypanosomal therapywouldbebetter tolerated,andtheoretically more effective, before immunosuppression develops or is induced.Althoughdataarelackingonthispoint,asecondarytheoreticalbenefit is apossible reduction in the riskof reactivation. Advancedrenal,hepatic,orcardiacdysfunctionwouldcertainly complicate therapy and constitutes a contraindication. We agree with Altclas et al that posttransplantation monitoring is indicatedwhetherornotacourseofantitrypanosomal treatment was completed prior to transplant. As stated in the Clinical Review, we recommend that treatment decisions be individualized for all adult patients with Chagas disease, balancing the potential benefit vs the risk of drug toxicity.


Prenatal Diagnosis | 2001

Knowledge of Down syndrome in pregnant women from different ethnic groups

Victor N. Chilaka; Justin C. Konje; Charles Stewart; Harini Narayan; David J. Taylor

The uptake of any screening test is influenced by knowledge of the condition being screened for. In the present study, the knowledge and the source of knowledge of women offered antenatal screening for Down syndrome (DS) was assessed by means of a self‐administered questionnaire. The questionnaire was administered to 300 consecutive women booking for antenatal care, of the 245 (82%) women who completed and returned the questionnaire, 117 (48%) were Caucasian, 85 (35%) were Asian born outside the UK, 32 (13%) were Asian born in the UK and ten (4%) belonged to other categories. Only 30% of the cohort had a good understanding of the condition. Racial groups other than Caucasian had a poorer understanding of DS. The factors which affected knowledge of DS included quality of spoken English, knowing an affected child, parity and religion. The most significant factor affecting acceptance of screening was the womans knowledge of DS. The source of information for the condition varied widely: 42% from a general practitioners (GP), 24% from the hospital and 16% from midwives. The proportion with good knowledge was similar in those women whose source of information was the GP (45%) and the midwife (41%). These proportions were, however, higher (though not significantly) when the source of information was from magazines and newspapers (67%) and from friends (53%). Uptake of the screening test was best in those with good knowledge (53%) compared to those with poor knowledge (23%) (p<0.02). Between 28% and 66% (depending on the ethnic group) of women had a screening blood test ‘allegedly’ without knowing why it had been performed. In order to improve uptake of the screening test for DS there is need for better education and counselling of women attending for antenatal care. Copyright


Endocrinology | 2008

Expression of the Endocannabinoid System in Human First Trimester Placenta and Its Role in Trophoblast Proliferation

Osama M. H. Habayeb; Anthony H. Taylor; Stephen C. Bell; David J. Taylor; Justin C. Konje

The endocannabinoid, anandamide, which binds to two major receptor proteins, the cannabinoid receptors (CBs) 1 and 2 (CB1 and CB2), has been shown to play a role in first trimester miscarriage possibly through impairment of the developing trophoblast. Although the precise molecular mechanisms underlying this are unknown, plasma anandamide levels are known to be regulated by the progesterone-induced enzyme, fatty acid amide hydrolase (FAAH). Here, we tested the hypothesis that temporal-spatial expression of FAAH, CB1, and CB2 is regulated during early pregnancy and that anandamide detrimentally alters trophoblast proliferation. Transcripts for CB1, CB2, and FAAH were demonstrated in first trimester trophoblast extracts with only the CB1 transcript being significantly regulated. The significant 4.7-fold increase in expression at wk 10 gestation was reduced to 8.9% of the peak value by wk 12. Transcripts for CB2 showed a similar pattern of expression but were not significantly induced. By contrast, FAAH transcript levels appeared to increase toward the end of the first trimester, but again did not reach significance. These observations were supported by immunohistochemical studies that demonstrated a similar pattern of expression at the protein level, with cellular localization for all three proteins concentrated within the syncytiotrophoblast layer. Anandamide also prevented BeWo trophoblast cell proliferation in a dose-dependent manner, with a 50-60% significant inhibition of cell proliferation with concentrations in excess of 3 mum. This effect was mediated through CB2. Together, these data provide insights into how elevated plasma anandamide levels increase the risk of first trimester miscarriage.

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