Imperial College London

Dr. Channa Jayasena MA PhD MRCP FRCPath

Faculty of MedicineDepartment of Metabolism, Digestion and Reproduction

Reader in Reproductive Endocrinology
 
 
 
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Contact

 

c.jayasena Website

 
 
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Location

 

6N5CCommonwealth BuildingHammersmith Campus

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Summary

 

Publications

Publication Type
Year
to

104 results found

Sharma A, Jayasena CN, 2019, Male infertility linked to risk of prostate cancer., BMJ, Vol: 366

Journal article

Dimakopoulou A, Jayasena CN, Radia UK, Algefari M, Minhas S, Oliver N, Dhillo WSet al., 2019, Animal Models of Diabetes-Related Male Hypogonadism, FRONTIERS IN ENDOCRINOLOGY, Vol: 10, ISSN: 1664-2392

Journal article

Prague J, voliotis M, Clarke S, Comninos A, Abbara A, Jayasena C, Roberts R, Yang L, veldhuis J, tsaneva-atanasova K, mcardle C, Dhillo Wet al., 2019, Determining the relationship between hot flushes and LH pulses in menopausal women using mathematical modelling, Journal of Clinical Endocrinology and Metabolism, Vol: 104, Pages: 3628-3636, ISSN: 0021-972X

BackgroundHypothalamic kisspeptin/neurokinin B/dynorphin (KNDy) neurones regulate LH pulsatility. It is widely accepted that the menopausal hot flush (HF) consistently synchronises with the LH pulse. This suggests that the hypothalamic KNDy neurones are implicated in generating LH pulsatility and HF. Using a modern immunoassay and mathematical modelling we investigated if the HF and LH pulse was consistently synchronised in menopausal women.MethodsEleven menopausal women (51-62yrs experiencing ≥7 HF/24hrs) attended for an 8 hour study where they self-reported HF and underwent peripheral blood sampling every 10 mins. LH pulsatility was determined using two mathematical models: blinded deconvolution analysis and Bayesian spectrum analysis. The probability that the LH pulse and HF event intervals matched was estimated using the interval distributions observed in our data.ResultsNinety-six HF were self-reported, and 82 LH pulses were identified by blinded deconvolution analysis. Using both models, the probability that the two event intervals matched was low in the majority of participants (mean P=0.24 (P=1 reflects perfect association)).InterpretationOur data challenges the widely accepted dogma that HF consistently synchronise with an LH pulse, and so has clinically important therapeutic and mechanistic implications.

Journal article

Agarwal A, Parekh N, Panner Selvam MK, Henkel R, Shah R, Homa ST, Ramasamy R, Ko E, Tremellen K, Esteves S, Majzoub A, Alvarez JG, Gardner DK, Jayasena CN, Ramsay JW, Cho CL, Saleh R, Sakkas D, Hotaling JM, Lundy SD, Vij S, Marmar J, Gosalvez J, Sabanegh E, Park HJ, Zini A, Kavoussi P, Micic S, Smith R, Busetto GM, Bakırcıoğlu ME, Haidl G, Balercia G, Puchalt NG, Ben-Khalifa M, Tadros N, Kirkman-Browne J, Moskovtsev S, Huang X, Borges E, Franken D, Bar-Chama N, Morimoto Y, Tomita K, Srini VS, Ombelet W, Baldi E, Muratori M, Yumura Y, La Vignera S, Kosgi R, Martinez MP, Evenson DP, Zylbersztejn DS, Roque M, Cocuzza M, Vieira M, Ben-Meir A, Orvieto R, Levitas E, Wiser A, Arafa M, Malhotra V, Parekattil SJ, Elbardisi H, Carvalho L, Dada R, Sifer C, Talwar P, Gudeloglu A, Mahmoud AMA, Terras K, Yazbeck C, Nebojsa B, Durairajanayagam D, Mounir A, Kahn LG, Baskaran S, Pai RD, Paoli D, Leisegang K, Moein MR, Malik S, Yaman O, Samanta L, Bayane F, Jindal SK, Kendirci M, Altay B, Perovic D, Harlev Aet al., 2019, Male oxidative stress infertility (MOSI): proposed terminology and clinical practice guidelines for management of idiopathic male infertility, World Journal of Mens Health, Vol: 37, ISSN: 2287-4208

Despite advances in the field of male reproductive health, idiopathic male infertility, in which a man has altered semen characteristics without an identifiable cause and there is no female factor infertility, remains a challenging condition to diagnose and manage. Increasing evidence suggests that oxidative stress (OS) plays an independent role in the etiology of male infertility, with 30% to 80% of infertile men having elevated seminal reactive oxygen species levels. OS can negatively affect fertility via a number of pathways, including interference with capacitation and possible damage to sperm membrane and DNA, which may impair the sperm's potential to fertilize an egg and develop into a healthy embryo. Adequate evaluation of male reproductive potential should therefore include an assessment of sperm OS. We propose the term Male Oxidative Stress Infertility, or MOSI, as a novel descriptor for infertile men with abnormal semen characteristics and OS, including many patients who were previously classified as having idiopathic male infertility. Oxidation-reduction potential (ORP) can be a useful clinical biomarker for the classification of MOSI, as it takes into account the levels of both oxidants and reductants (antioxidants). Current treatment protocols for OS, including the use of antioxidants, are not evidence-based and have the potential for complications and increased healthcare-related expenditures. Utilizing an easy, reproducible, and cost-effective test to measure ORP may provide a more targeted, reliable approach for administering antioxidant therapy while minimizing the risk of antioxidant overdose. With the increasing awareness and understanding of MOSI as a distinct male infertility diagnosis, future research endeavors can facilitate the development of evidence-based treatments that target its underlying cause.

Journal article

Dearing C, Jayasena C, Lindsay K, 2019, Can the sperm class analyser (SCA) CASA-Mot system for human sperm motility analysis reduce imprecision and operator subjectivity and improve semen analysis?, Human Fertility, ISSN: 1464-7273

Semen analysis (SA) is considered mandatory for suspected male infertility although its clinical value has recently become questionable. Sperm motility is an essential parameter for SA, but is limited by high measurement uncertainty, which includes operator subjectivity. Computer-assisted sperm analysis (CASA) can reduce measurement uncertainty compared with manual SA. The objective of this study was to determine whether the Sperm Class Analyser (SCA) CASA-Mot system could reduce specific components of sperm motility measurement uncertainty compared with the World Health Organization (WHO) manual method in a single laboratory undertaking routine diagnostic SA. The study examined: (i) operator subjectivity; (ii) precision, (iii) accuracy against internal and external quality standards; and (iv) a pilot sub-study examining the potential to predict an IVF fertilisation rate. Compared with the manual WHO method of SA on 4000 semen samples, SCA reduces but does not completely eliminate operator subjectivity. Study SCA and CASA-Mot are useful tools for well-trained staff that allow rapid, high-number sperm motility categorization with less analytical variance than the manual equivalent. Our initial data suggest that SCA motility may have superior predictive potential compared with the WHO manual method for predicating IVF fertilization.

Journal article

Prague JK, Roberts RE, Comninos AN, Clarke S, Jayasena CN, Mohideen P, Lin VH, Stern TP, Panay N, Hunter MS, Webber LC, Dhillo WSet al., 2019, Neurokinin 3 Receptor Antagonism Rapidly Improves Vasomotor Symptoms With Sustained Duration of Action, Obstetrical & Gynecological Survey, Vol: 74, Pages: 221-222, ISSN: 0029-7828

Journal article

Tharakan T, Miah S, Jayasena C, Minhas Set al., 2019, Investigating the basis of sexual dysfunction during late-onset hypogonadism, F1000Research, Vol: 8, ISSN: 2046-1402

Late-onset hypogonadism (LOH) is the term used to describe the decline in serum testosterone levels associated with increasing age in men above 40 years. A number of symptoms are attributed to LOH, but the most common association is that of sexual dysfunction. LOH has recently come under greater scrutiny with the widespread use of testosterone therapy, and concerns regarding the efficacy and safety of testosterone replacement therapy have been raised. In particular, the cardiovascular safety and the beneficial effects of testosterone replacement therapy on general health have been questioned. This review will give an overview of the current evidence for the relationship of LOH and male sexual dysfunction.

Journal article

Jayasena CN, Alkaabi FM, Liebers CS, Handley T, Franks S, Dhillo WSet al., 2019, A systematic review of randomised controlled trials investigating the efficacy and safety of testosterone therapy for female sexual dysfunction in postmenopausal women, Clinical Endocrinology, Vol: 90, Pages: 391-414, ISSN: 1365-2265

The clinical sequelae of oestrogen deficiency during menopause are undoubted. However, the pathophysiological role of testosterone during the menopause is less clear. Several randomised, placebo-controlled clinical trials suggest that testosterone therapy improves sexual function in post-menopausal women. Some studies suggest that testosterone therapy has additional effects which include increased bone mineral density and decreased serum high density lipoprotein (HDL) cholesterol. Furthermore, the long-term safety profile of testosterone therapy in post-menopausal women is not clear. This article will provide a concise and critical summary of the literature, to guide clinicians treating post-menopausal women. This article is protected by copyright. All rights reserved.

Journal article

Miah S, Tharakan T, Gallagher KA, Shah TT, Winkler M, Jayasena CN, Ahmed HU, Minhas Set al., 2019, The effects of testosterone replacement therapy on the prostate: a clinical perspective [version 1; referees: 2 approved], F1000Research, Vol: 8, ISSN: 2046-1402

Male hypogonadism is a clinical syndrome characterized by low testosterone and symptoms of androgen deficiency. Prostate cancer remains a significant health burden and cause of male mortality worldwide. The use of testosterone replacement therapy drugs is rising year-on-year for the treatment of androgen deficiency and has reached global proportions. As clinicians, we must be well versed and provide appropriate counseling for men prior to the commencement of testosterone replacement therapy. This review summarizes the current clinical and basic science evidence in relation to this commonly encountered clinical scenario. There is gathering evidence that suggests, from an oncological perspective, that it is safe to commence testosterone replacement therapy for men who have a combination of biochemically confirmed androgen deficiency and who have either had definitive treatment of their prostate cancer or no previous history of this disease. However, patients must be made aware and cautioned that there is a distinct lack of level 1 evidence. Calls for such studies have been made throughout the urological and andrological community to provide a definitive answer. For those with a diagnosis of prostate cancer that remains untreated, there is a sparsity of evidence and therefore clinicians are "pushing the limits" of safety when considering the commencement of testosterone replacement therapy.

Journal article

Jayasena CN, Radia UK, Figueiredo M, Revill LF, Dimakopoulou A, Osagie M, Vessey W, Regan L, Rai R, Dhillo WSet al., 2019, Reduced testicular steroidogenesis and increased semen oxidative stress in male partners as novel markers of recurrent miscarriage, Clinical Chemistry, Vol: 65, Pages: 161-169, ISSN: 1530-8561

BACKGROUND: Recurrent pregnancy loss, (RPL) affecting 1%–2% of couples, is defined as ≥3 consecutive pregnancy losses before 20-week' gestation. Women with RPL are routinely screened for etiological factors, but routine screening of male partners is not currently recommended. Recently it has been suggested that sperm quality is reduced in male partners of women with RPL, but the reasons underlying this lower quality are unclear. We hypothesized that these men may have underlying impairments of reproductive endocrine and metabolic function that cause reductions in sperm quality.METHODS: After ethical approval, reproductive parameters were compared between healthy controls and male partners of women with RPL. Semen reactive oxygen species (ROS) were measured with a validated inhouse chemiluminescent assay. DNA fragmentation was measured with the validated Halosperm method.RESULTS: Total sperm motility, progressive sperm motility, and normal morphology were all reduced in the RPL group vs controls. Mean ±SE morning serum testosterone (nmol/L) was 15% lower in RPL than in controls (controls, 19.0 ± 1.0; RPL, 16.0 ± 0.8; P < 0.05). Mean ±SE serum estradiol (pmol/L) was 16% lower in RPL than in controls (controls, 103.1 ± 5.7; RPL, 86.5 ± 3.4; P < 0.01). Serum luteinizing hormone and follicle-stimulating hormone were similar between groups. Mean ±SE ROS (RLU/sec/106 sperm) were 4-fold higher in RPL than in controls (controls, 2.0 ± 0.6; RPL, 9.1 ± 4.1; P < 0.01). Mean ±SE sperm DNA fragmentation (%) was 2-fold higher in RPL than in controls (controls, 7.3 ± 1.0; RPL, 16.4 ± 1.5; P < 0.0001).CONCLUSIONS: Our data suggest that male partners of women with RPL have impaired reproductive endocrine function, increased levels of semen ROS, and sperm DNA fragmentation. Routine reproductive assessment of the male partners may be beneficial in RPL.

Journal article

Rose AM, Luo R, Radia UK, Kalirai H, Thornton S, Luthert PJ, Jayasena CN, Verity DH, Coupland SE, Rose GEet al., 2018, Detection of mutations in SF3B1, EIF1AX and GNAQ in primary orbital melanoma by candidate gene analysis, BMC Cancer, Vol: 18, ISSN: 1471-2407

BackgroundOcular melanoma is a rare but often deadly malignancy that arises in the uvea (commonest primary site), conjunctiva or the orbit. Primary orbital melanoma (POM) is exceedingly rare, with approximately 60 cases reported to date. Despite recent advances in our understanding of the genetics of primary uveal and conjunctival melanomas, this information is lacking for POM.MethodsDNA was extracted from 12 POM tissues, with matched germline DNA (where available). MLPA was conducted to detect chromosomal alterations and Sanger sequencing used to identify point mutations in candidate melanoma driver genes (BRAF, NRAS, KRAS, GNA11, GNAQ), and other genes implicated in melanoma prognosis (EIF1AX, SF3B1). Immunohistochemistry was performed to analyse BAP1 nuclear expression.ResultsMLPA detected copy number alterations in chromosomes 1p, 3, 6 and 8. Sequencing of melanoma driver genes revealed GNAQ (p.Q209L) mutations in two samples; although it is possible that these samples represent extraocular spread of an occult uveal melanoma. A recurrent mutation in SF3B1 (p.R625H) was observed in indolent, but not aggressive, tumours; a mutation in EIF1AX (p.N4S) was detected in one patient with non-aggressive disease.ConclusionsEIF1AX and SF3B1 mutations appear have a role in determining the clinical course of POM and detection of these changes could have clinical significance. Further in depth analysis of this rare group using differing ‘omic technologies will provide novel insights into tumour pathogenesis.

Journal article

Jayasena CN, Luo R, Dimakopoulou A, Dearing C, Clarke H, Patel N, Stroud T, Seyani L, Ramsay J, Dhillo WSet al., 2018, Prevalence of abnormal semen analysis and levels of adherence with fertility preservation in men undergoing therapy for newly diagnosed cancer: A retrospective study in 2906 patients, Clinical Endocrinology, Vol: 89, Pages: 798-804, ISSN: 1365-2265

BACKGROUND: Sperm cryopreservation (freezing) should be offered to all men with cancer due to risk of infertility. However, many men with cancer already have impaired spermatogenesis prior to sperm cryopreservation. Furthermore, physical ill-health may hinder attendance of freeze visits. Investigating both the distribution of sperm functions and freeze attendance rates in men with newly diagnosed cancer, may identify patients benefiting from targeted reproductive fertility support. METHODS: We performed a retrospective study of 2906 male patients undergoing sperm cryopreservation prior to cancer therapy at a single UK tertiary centre between 1989 and 2013; all patients were asked to attend three hospital semen collection visits prior to cancer therapy. RESULTS: Fifteen per cent (433/2906) of men with newly diagnosed cancer had severely impaired semen quality (i.e., sperm total motile count, TMC < 1 million) during the first semen collection visit. However, patients with severely impaired semen quality had the poorest attendance of subsequent semen collection visits despite being requested to do so (non-attendance in TMC < 1 million: 43.4%; TMC < 1-30 million: 35.7%, P < 0.05 vs. <1 million; TMC > 30 million: 33.2%, P < 0.01 vs. <1 million). CONCLUSIONS: This study expands understanding of the semen quality of men with newly diagnosed cancer, and their ability to adhere to fertility preservation recommendations. Our data suggest that patients with the poorest semen quality paradoxically suffer the poorest attendance rates of sperm cryopreservation appointments prior to commencing cancer therapy. We suggest that additional support may be of clinical benefit to men with newly diagnosed cancer and TMC < 1 million sperm.

Journal article

Comninos A, Demetriou L, Wall M, Shah A, Clarke S, Narayanaswamy S, Nesbitt A, Izzi-Engbeaya C, Prague J, Abbara A, Ratnasabapathy R, Yang LY, Salem V, Nijher G, Jayasena C, Tanner M, Bassett P, Mehta A, McGonigle J, Rabiner E, Bloom S, Dhillo Wet al., 2018, Modulations of human resting brain connectivity by Kisspeptin enhance sexual and emotional Functions, JCI insight, Vol: 3, ISSN: 2379-3708

BACKGROUND. Resting brain connectivity is a crucial component of human behavior demonstrated by disruptions in psychosexual and emotional disorders. Kisspeptin, a recently identified critical reproductive hormone, can alter activity in certain brain structures but its effects on resting brain connectivity and networks in humans remain elusive.METHODS. We determined the effects of kisspeptin on resting brain connectivity (using functional neuroimaging) and behavior (using psychometric analyses) in healthy men, in a randomized double-blinded 2-way placebo-controlled study.RESULTS. Kisspeptin’s modulation of the default mode network (DMN) correlated with increased limbic activity in response to sexual stimuli (globus pallidus r = 0.500, P = 0.005; cingulate r = 0.475, P = 0.009). Furthermore, kisspeptin’s DMN modulation was greater in men with less reward drive (r = –0.489, P = 0.008) and predicted reduced sexual aversion (r = –0.499, P = 0.006), providing key functional significance. Kisspeptin also enhanced key mood connections including between the amygdala-cingulate, hippocampus-cingulate, and hippocampus–globus pallidus (all P < 0.05). Consistent with this, kisspeptin’s enhancement of hippocampus–globus pallidus connectivity predicted increased responses to negative stimuli in limbic structures (including the thalamus and cingulate [all P < 0.01]).CONCLUSION. Taken together, our data demonstrate a previously unknown role for kisspeptin in the modulation of functional brain connectivity and networks, integrating these with reproductive hormones and behaviors. Our findings that kisspeptin modulates resting brain connectivity to enhance sexual and emotional processing and decrease sexual aversion, provide foundation for kisspeptin-based therapies for associated disorders of body and mind.

Journal article

Wall J, Jayasena CN, 2018, Diagnosing male infertility, BMJ-BRITISH MEDICAL JOURNAL, Vol: 363, ISSN: 1756-1833

Journal article

Dimakopoulou A, Jayasena CN, 2018, Seminal reactive oxygen species, a novel biochemical assay for testing male fertility?, Biochemist, Vol: 40, Pages: 12-13, ISSN: 0954-982X

Infertility is defined as a failure to achieve a positive pregnancy test over 12 months of regular unprotected sex. It is a devastating condition affecting 15% of couples and is socially marginalizing. Despite significant focus on the female, nearly half of cases are in fact due to poor sperm function in the male partner. It is therefore surprising that despite the existence of numerous diagnostic tools and management options currently available for female infertility, very few exist for their male counterparts. So, what can we do to diagnose men with impaired fertility promptly and direct couples to effective management strategies?.

Journal article

Abbara A, Narayanaswamy S, Izzi-Engbeaya C, Comninos A, Clarke S, Malik Z, Papadopoulou D, Coblentz A, Sarang Z, Bassett P, Jayasena C, Dhillo Wet al., 2018, Hypothalamic response to kisspeptin and pituitary response to GnRH are preserved in healthy older men, Neuroendocrinology, Vol: 106, ISSN: 0028-3835

Background: Male testosterone levels decline by 1% per year from the age of 40yrs. Whilst a primary testicular deficit occurs, hypothalamic or pituitary dysregulation may also coexist. This study aimed to compare the hypothalamic response to kisspeptin and the pituitary response to GnRH of older men with those of young men. Methods: Following 1 hour of baseline sampling, healthy older men (n=5, mean age 59.3±2.9yrs) received a 3 hour intravenous infusion (IVI) of either: vehicle, kisspeptin-54 0.1, 0.3, 1.0nmol/kg/h, or GnRH 0.1nmol/kg/h on 5 different study days. Serum gonadotropins and total testosterone were measured every 10 minutes and compared to young men (n=5/group) (mean age 28.9±2.0yrs) with a similar BMI (24 kg/m2) who underwent the same protocol. Results: Kisspeptin and GnRH significantly stimulated serum gonadotropin release in older men compared to vehicle (P<0.001 for all groups). Gonadotropin response to kisspeptin was at least preserved in older men when compared with young men. At the highest dose of kisspeptin (1.0nmol/kg/h), a significantly greater LH (P=0.003) response was observed in older men. The FSH response to GnRH was increased in older men (P=0.002), but the LH response was similar (P=0.38). Serum testosterone rises following all doses of kisspeptin (P≤0.009) were reduced in older men. Conclusions: Our data suggests that healthy older men without late onset hypogonadism (LOH) have preserved hypothalamic response to kisspeptin and pituitary response to GnRH, but impaired testicular response. Further work is required to investigate the use of kisspeptin to identify hypothalamic deficits in men with LOH.

Journal article

Rose A, Radia U, Luo R, Kalirai H, Jayasena C, Luthert P, Coupland S, Rose Get al., 2018, Multiple primary malignancies and prolonged survival in a patient with widespread metastatic cutaneous melanoma, Melanoma Research, Vol: 28, Pages: 163-166, ISSN: 0960-8931

Journal article

Prague JK, Dhillo W, Roberts R, Comninos A, Clarke S, Jayasena C, Mohideen P, Lin V, Stern T, Panay N, Hunter M, Webber Let al., Neurokinin 3 receptor antagonism rapidly improves vasomotor symptoms with sustained duration of action, Menopause, Vol: 25, ISSN: 1530-0374

Objective: Seventy percent of postmenopausal women experience vasomotor symptoms, which can be highly disruptive and persist for years. Hormone therapy and other treatments have variable efficacy and/or side effects. Neurokinin B signaling increases in response to estrogen deficiency and has been implicated in hot flash (HF) etiology. We recently reported that a neurokinin 3 receptor (NK3R) antagonist reduces HF in postmenopausal women after 4 weeks of treatment. In this article we report novel data from that study, which shows the detailed time course of this effect.Methods: Randomized, double-blind, placebo-controlled, single-center, crossover trial of an oral NK3R antagonist (MLE4901) for vasomotor symptoms in women aged 40 to 62 years, experiencing ≥7 HF/24 hours some of which were reported as bothersome or severe (Clinicaltrials.gov NCT02668185). Thirty-seven women were randomized and included in an intention-to-treat analysis. To ascertain the therapeutic profile of MLE4901, a post hoc time course analysis was completed.Results: By day 3 of treatment with MLE4901, HF frequency reduced by 72% (95% CI, −81.3 to −63.3%) compared with baseline (51 percentage point reduction compared with placebo, P < 0.0001); this effect size persisted throughout the 4-week dosing period. HF severity reduced by 38% compared with baseline by day 3 (95% CI, −46.1 to −29.1%) (P < 0.0001 compared with placebo), bother by 39% (95% CI, −47.5 to −30.1%) (P < 0.0001 compared with placebo), and interference by 61% (95% CI, −79.1 to −43.0%) (P = 0.0006 compared with placebo); all continued to improve throughout the 4-week dosing period (to −44%, −50%, and −70%, respectively by day 28, all P < 0.0001 compared with placebo).Conclusions: NK3R antagonism rapidly relieves vasomotor symptoms without the need for estrogen exposure.

Journal article

Ali SN, Jayasena CN, Sam AH, 2018, Which patients with gynaecomastia require more detailed investigation?, CLINICAL ENDOCRINOLOGY, Vol: 88, Pages: 360-363, ISSN: 0300-0664

Gynaecomastia may be due to medication, chronic liver or kidney disease, hypogonadism (primary or secondary to pituitary disease) or hyperthyroidism. Having excluded these aetiologies, it is imperative to be vigilant for underlying malignancy causing gynaecomastia. These include human chorionic gonadotrophin‐secreting testicular and extratesticular tumours and oestrogen‐secreting testicular tumours and feminising adrenal tumours.

Journal article

de Tassigny XD, Jayasena CN, Murphy KG, Dhillo WS, Colledge WHet al., 2018, Correction: Mechanistic insights into the more potent effect of KP-54 compared to KP-10 in vivo, PLoS ONE, Vol: 13, ISSN: 1932-6203

Journal article

Rose A, Luthert P, Jayasena C, Verity D, Rose GEet al., 2017, Primary orbital melanoma: presentation, treatment and long-term outcomes for 13 patients, Frontiers in Oncology, Vol: 7, ISSN: 2234-943X

Background: Periocular melanoma is a rare but often deadly malignancy that arises in the uvea (commonest origin), conjunctiva or orbit (rarest primary site). Melanoma accounts for 5–10% of metastatic/secondary orbital malignancies, but only a tiny proportion of primary orbital neoplasia. Primary orbital melanoma (POM) is exceedingly rare, with approximately 50 cases reported to date.Methods: All patients seen in the orbital unit at a tertiary referral hospital (1991–2016) with a biopsy-proven diagnosis of POM were identified from a diagnostic database and were studied. The case notes, imaging, surgical approach, and histology were reviewed.Results: Thirteen patients (five male; 38%) presented with isolated malignant melanoma of the orbit, for which no other primary site was identified at presentation or during an average follow-up of 44 months (median 22; range 0–13 years). The patients presented between the ages of 40 and 84 years (mean 55.5; median 48 years) and typically gave a short history of rapidly increasing proptosis and eyelid swelling. On the basis of history, a malignant lesion was suspected in most patients and all underwent incisional biopsy, with debulking of the mass in 10 (77%) patients, and skin-sparing exenteration in 3/13 (23%). Ten patients underwent orbital radiotherapy and the survival to date ranged from 9 months to 14 years (mean 55 months; median 23 months); two patients received solely palliative care for widespread disease and one patient refused orbital radiotherapy. Five of the 13 (38%) patients died from the disease.Discussion: POM is a very rare malignancy, but clinical analysis of this cohort gives insight into disease presentation and prognosis. The tumor typically presents with a rapidly progressive, well-defined mass that is, in some cases, amenable to macroscopically intact excision. Unusual for malignant melanoma, some of these patients can show an unusually long period of quiescent disease after surgical debul

Journal article

Algeffari M, Jayasena CN, MacKeith P, Thapar A, Dhillo WS, Oliver Net al., 2017, Testosterone therapy for sexual dysfunction in men with Type 2 diabetes: a systematic review and meta-analysis of randomized controlled trials., Diabetic Medicine, Vol: 35, Pages: 195-202, ISSN: 0742-3071

AIM: To evaluate the effectiveness of testosterone therapy on a range of sexual function domains in men with Type 2 diabetes. METHOD: Electronic databases were searched for studies investigating the effect of testosterone therapy on sexual function in men with Type 2 diabetes. All randomized controlled trials were considered for inclusion if they compared the efficacy of testosterone therapy with that of placebo and reported sexual function outcomes. Statistical analysis was performed using a random-effects model, and heterogeneity was expressed using the I2 statistic. RESULTS: A total of 611 articles were screened. Six randomized control trials, in a total of 587 men with Type 2 diabetes, were eligible for inclusion. The pooled data suggested that testosterone therapy improves sexual desire (random-effects pooled effect size 0.314; 95% CI 0.082-0.546) and erectile function (random-effects pooled effect size 0.203; 95% CI 0.007-0.399) when compared with control groups. Testosterone therapy had no significant effect on constitutional symptoms or other sexual domains compared with control groups. No studies have investigated the incidence of prostate cancer, fertility and cardiovascular disease after testosterone therapy in men with Type 2 diabetes. CONCLUSION: Testosterone therapy may moderately improve sexual desire and erectile function in men with Type 2 diabetes; however, available data are limited, and the long-term risks of testosterone therapy are not known in this specific patient group. We conclude that testosterone therapy is a potential treatment for men with Type 2 diabetes non-responsive to phosphodiesterase-5 inhibitors. Testosterone therapy could be considered for men with Type 2 diabetes when potential risks and benefits of therapy are carefully considered and other therapeutic options are unsuitable.

Journal article

Lal V, Jayasena CN, Quinton R, 2017, The emergence of sarcopenia as an important entity in older people, Clinical Medicine, Vol: 17, Pages: 590-590, ISSN: 1470-2118

Journal article

Dearing CG, Jayasena CN, Lindsay KS, 2017, Human sperm cryopreservation in cancer patients: Links with deprivation and mortality, CRYOBIOLOGY, Vol: 79, Pages: 9-13, ISSN: 0011-2240

Journal article

Rozati H, Handley T, Jayasena CN, 2017, Process and Pitfalls of Sperm Cryopreservation., J Clin Med, Vol: 6, ISSN: 2077-0383

Sperm cryopreservation has been utilized routinely for over 40 years to preserve fertility in men undergoing cancer therapy and allow conception for infertile couples. This article provides a concise and up-to-date review of the literature and covers the latest advances in sperm cryopreservation and its array of clinical indications. Over recent years, the scope of clinical indications used for sperm cryopreservation has expanded widely. Consequently, more patient groups are eligible for sperm freezing, requiring specialist resources and higher running costs. Although sperm cryopreservation prior to cancer therapy is readily available in many countries, referral rates by oncology specialists and levels of patient engagement with cryopreservation services are both reported as low. Furthermore, sperm banking continues to raise ethical issues such whether sperm donation should be anonymous and whether sperm can be utilized posthumously by the surviving partner without consent from the patient. This review focuses on the technological advances and ethical controversies in sperm cryopreservation, and how better understanding of these issues could lead to improved access to fertility preserving treatment for patients.

Journal article

Wernig F, Jayasena CN, Dhillo WS, 2017, Carcinoid syndrome and neuroendocrine tumours, Medicine, Vol: 45, Pages: 543-546, ISSN: 1357-3039

Neuroendocrine tumours (NETs) arise from the gastrointestinal tract, pancreas, bronchi or other rare primary sites and comprise a variety of different tumour types. Carcinoid tumours are the most common. NETs can be associated with a variety of clinical syndromes. For instance, classic symptoms of carcinoid syndrome, such as flushing and diarrhoea, occur because of the release of hormones, including serotonin, tachykinins and peptide hormones. However, most NETs are non-secretory in nature and are detected incidentally or through compression of surrounding structures. Liver metastasis has usually already occurred at the time of diagnosis. Surgery can be curative if disease is entirely localized. Injections of somatostatin analogues such as octreotide are the mainstay of non-surgical treatment for NETs. Surgical debulking and embolization techniques are useful to reduce tumour bulk in patients who remain symptomatic despite medical treatment. Peptide receptor radionucleotide therapy using radiolabelled somatostatin analogues has recently been shown to prolong progression-free survival. Furthermore, several novel agents, such as everolimus, have emerged in the treatment of patients with metastatic disease. This article aims to summarize the pathophysiology and clinical features of NETs, with a focus on carcinoid syndrome. It also discusses recent advances in clinical management of NETs.

Journal article

Rose AM, Cowen S, Jayasena CN, Verity DH, Rose GEet al., 2017, Presentation, treatment and prognosis for secondary melanoma within the orbit, Frontiers in Oncology, Vol: 7, ISSN: 2234-943X

Background: Ocular melanoma is a rare but often deadly malignancy that arises in the uvea, conjunctiva, or orbit. Uveal melanoma is the most common type, with conjunctival melanoma being the second most frequently observed. Melanoma accounts for 5–10% of metastatic or secondary orbital malignancies, but only a minute proportion of primary orbital neoplasia. The aim of this study was to characterize the clinical presentation, treatment, and prognosis in patients presenting with melanoma metastatic to, or secondary within, the orbit.Methods: A retrospective cohort study of patients presenting to a tertiary referral orbital unit from 1982 to 2016 was performed. Eighty-nine patients with biopsy-proven diagnosis of melanoma within the orbit were included in the study. The clinical notes, radiological imaging, histology, surgical notes, and outcome data for the patients were reviewed. The main outcome measures of interest were the interval between primary malignant melanoma and orbital presentation, survival after orbital presentation, and clinical parameters (such as gender, age at presentation, and treatment approach).Results: The commonest primary source of tumor was choroidal melanoma, with conjunctival and cutaneous melanomas being relatively common; eyelid and naso-sinus tumors occurred in a few cases. The mean age at presentation with orbital disease was 65 years (31–97 years). The interval between primary malignancy and orbital disease (either local spread/recurrence or true metastatic disease) showed wide variability, with almost one-third of patients having orbital disease at the time of primary diagnosis, but others presenting many years later; indeed, the longest orbital disease-free interval was over 34 years. Twenty-three patients were considered to have had late orbital metastases—that is, at more than 36 months after primary tumor. The median survival following presentation with orbital involvement was 24 months. Patients with tumors of c

Journal article

Prague JK, Roberts RE, Comninos AN, Clarke S, Jayasena CN, Nash Z, Doyle C, Papadopoulou D, Bloom SR, Mohideen P, Lin V, Stern T, Panay N, Hunter MS, Veldhuis JD, Webber LC, Huson L, Dhillo WSet al., 2017, Neurokinin 3 receptor antagonism is a highly effective, novel treatment for menopausal hot flushes with rapid onset: a phase 2, randomised, double-blind, placebo-controlled trial, Lancet, Vol: 389, Pages: 1809-1820, ISSN: 0140-6736

BackgroundHot flushes affect 70% of menopausal women and often severely impact physical, psychosocial, sexual, and overall wellbeing. Hormone replacement therapy is effective but is not without risk. Neurokinin B signalling is increased in menopausal women, and has been implicated as an important mediator of hot flushes.MethodsThis phase 2, randomised, double-blind, placebo-controlled, single-centre, crossover trial assessed the effectiveness of an oral neurokinin 3 receptor antagonist (MLE4901) on menopausal hot flushes. Eligible participants were healthy women aged 40–62 years, having seven or more hot flushes in every 24 h of which some were reported as being severe or bothersome, who had not had a menstrual period for at least 12 months, and who had not been taking any medication shown to improve menopausal flushes in the preceding 8 weeks. Participants received 4 weeks of MLE4901 (40 mg, orally, twice daily) and placebo (orally, twice daily) in random order separated by a 2 week washout period. Randomisation was completed by a central computer, and participants were allocated to treatment number in numerical order. The primary outcome was the total number of hot flushes during the final week of both treatment periods. Analyses were by intention to treat and per protocol using generalised linear mixed models and standard crossover analysis. All analyses were prespecified in the study protocol. The trial is registered at ClinicalTrials.gov, number NCT02668185.Findings68 women were screened between Feb 3 and Oct 10, 2016, of which 37 were randomly assigned and included in an intention-to-treat analysis. 28 participants completed the trial and were included in a per-protocol analysis. MLE4901 significantly reduced the total weekly number of hot flushes by 45 percentage points (95% CI 22–67) compared with the placebo (intention-to-treat adjusted means: placebo 49·01 [95% CI 40·81–58·56] vs MLE4901 19·35 [15·99&nda

Journal article

de Tassigny XD, Jayasena C, Murphy KG, Dhillo WS, Colledge WHet al., 2017, Mechanistic insights into the more potent effect of KP-54 compared to KP-10 in vivo, PLOS One, Vol: 12, ISSN: 1932-6203

Kisspeptins regulate the mammalian reproductive axis by stimulating release of gonadotrophin releasing hormone (GnRH). Different length kisspeptins (KP) are found of 54, 14, 13 or 10 amino-acids which share a common C-terminal 10-amino acid sequence. KP-54 and KP-10 have been widely used to stimulate the reproductive axis but data suggest that KP-54 and KP-10 are not equally effective at eliciting reproductive hormone secretion after peripheral delivery. To confirm this, we analysed the effect of systemic administration of KP-54 or KP-10 on luteinizing hormone (LH) secretion into the bloodstream of male mice. Plasma LH measurements 10 min or 2 hours after kisspeptin injection showed that KP-54 can sustain LH release far longer than KP-10, suggesting a differential mode of action of the two peptides. To investigate the mechanism for this, we evaluated the pharmacokinetics of the two peptides in vivo and their potential to cross the blood brain barrier (BBB). We found that KP-54 has a half-life of ~32 min in the bloodstream, while KP-10 has a half-life of ~4 min. To compensate for this difference in half-life, we repeated injections of KP-10 every 10 min over 1 hr but failed to reproduce the sustained rise in LH observed after a single KP-54 injection, suggesting that the failure of KP-10 to sustain LH release may not just be related to peptide clearance. We tested the ability of peripherally administered KP-54 and KP-10 to activate c-FOS in GnRH neurons behind the blood brain barrier (BBB) and found that only KP-54 could do this. These data are consistent with KP-54 being able to cross the BBB and suggest that KP10 may be less able to do so.

Journal article

Prague JK, Roberts RE, Comninos AC, Clarke S, jayasena CN, bloom S, mohideen P, panay N, hunter M, veldhuis J, webber L, huson L, Dhillo WSet al., 2017, Neurokinin 3 receptor antagonism as a novel treatment for menopausal hot flushes: a phase 2, randomised, double-blind, placebo-controlled trial, Lancet, Vol: 389, Pages: 1809-1820, ISSN: 1474-547X

BackgroundHot flushes affect 70% of menopausal women and often severely impact physical, psychosocial, sexual, and overall wellbeing. Hormone replacement therapy is effective but is not without risk. Neurokinin B signalling is increased in menopausal women, and has been implicated as an important mediator of hot flushes.MethodsThis phase 2, randomised, double-blind, placebo-controlled, single-centre, crossover trial assessed the effectiveness of an oral neurokinin 3 receptor antagonist (MLE4901) on menopausal hot flushes. Eligible participants were healthy women aged 40–62 years, having seven or more hot flushes in every 24 h of which some were reported as being severe or bothersome, who had not had a menstrual period for at least 12 months, and who had not been taking any medication shown to improve menopausal flushes in the preceding 8 weeks. Participants received 4 weeks of MLE4901 (40 mg, orally, twice daily) and placebo (orally, twice daily) in random order separated by a 2 week washout period. Randomisation was completed by a central computer, and participants were allocated to treatment number in numerical order. The primary outcome was the total number of hot flushes during the final week of both treatment periods. Analyses were by intention to treat and per protocol using generalised linear mixed models and standard crossover analysis. All analyses were prespecified in the study protocol. The trial is registered at ClinicalTrials.gov, number NCT02668185.Findings68 women were screened between Feb 3 and Oct 10, 2016, of which 37 were randomly assigned and included in an intention-to-treat analysis. 28 participants completed the trial and were included in a per-protocol analysis. MLE4901 significantly reduced the total weekly number of hot flushes by 45 percentage points (95% CI 22–67) compared with the placebo (intention-to-treat adjusted means: placebo 49·01 [95% CI 40·81–58·56] vs MLE4901 19·35 [15·99&nda

Journal article

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