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Dive into the research topics where Ronda F. Greaves is active.

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Featured researches published by Ronda F. Greaves.


Pediatric Pulmonology | 2014

Sixty-Five Years Since the New York Heat Wave: Advances in Sweat Testing for Cystic Fibrosis

Jake T.B. Collie; R. John Massie; Oliver A. H. Jones; Vicky A. LeGrys; Ronda F. Greaves

The sweat test remains important as a diagnostic test for cystic fibrosis (CF) and has contributed greatly to our understanding of CF as a disease of epithelial electrolyte transport. The standardization of the sweat test, by Gibson and Cooke [Gibson and Cooke (1959) Pediatrics 1959;23:5], followed observations of excessive dehydration amongst patients with CF and confirmed the utility as a diagnostic test. Quantitative pilocarpine iontophoresis remains the gold standard for sweat induction, but there are a number of collection and analytical methods. The pathophysiology of electrolyte transport in sweat was described by Quinton [Quinton (1983) Nature 1983;301:421–422], and this complemented the developments in genetics that discovered the cystic fibrosis transmembrane conductance regulator (CFTR), an epithelial‐based electrolyte transport protein. Knowledge of CF has since increased rapidly and further developments in sweat testing include: new collection methods, further standardization of the technique with international recommendations and age related reference intervals. More recently, sweat chloride values have been used as proof of effect for the new drugs that activate CFTR. However, there remain issues with adherence to sweat test guidelines in many countries and there are gaps in our knowledge, including reference intervals for some age groups and stability of sweat samples in transport. Furthermore, modern methods of elemental quantification need to be explored as alternatives to the original analytical methods for sweat electrolyte measurement. The purpose of this review is therefore to describe the development of the sweat test and consider future directions. Pediatr Pulmonol. 2014; 49:106–117.


Pediatrics | 2008

Luteinizing Hormone and Follicle-Stimulating Hormone Levels in Extreme Prematurity: Development of Reference Intervals

Ronda F. Greaves; Rodney W. Hunt; Angela S. Chiriano; Margaret Zacharin

OBJECTIVES. Establishing pediatric reference intervals has always been challenging, with most ranges used in pediatric laboratories developed over many years. The clinical interpretation of gonadotropins is important in the context of ambiguous genitalia. The aim of this study was to develop reference intervals for luteinizing hormone and follicle-stimulating hormone in infants born between 24 and 29 weeks’ gestation. METHODS. Samples were collected at 0 to 43 days after birth from 82 premature infants born <30 weeks’ gestation for analysis of luteinizing hormone and follicle-stimulating hormone by automated immunochemiluminometric immunoassays. RESULTS. The 43 male infants demonstrated a range of luteinizing hormone levels from 0.1 to 13.4 IU/L and of follicle-stimulating hormone levels from 0.3 to 4.6 IU/L. The 39 female infants demonstrated a range of luteinizing hormone levels from 0.2 to 54.4 IU/L and of follicle-stimulating hormone levels from 1.2 to 167.0 IU/L. The ratio of luteinizing hormone/follicle-stimulating hormone levels differed with males, ranging from 0.3 to 9.4, and females, at <0.5. CONCLUSION. These data provide guidance for the interpretation of luteinizing hormone and follicle-stimulating hormone levels for the first 6 weeks of life in extremely premature infants born between 24 and 29 weeks’ gestation. The availability of age-appropriate reference intervals is essential for correct and timely interpretation of biochemical results to the clinician.


European Journal of Endocrinology | 2017

Steroid hormone analysis in diagnosis and treatment of DSD: position paper of EU COST Action BM 1303 ‘DSDnet’

Alexandra Kulle; N Krone; P.-M. Holterhus; G Schuler; Ronda F. Greaves; Anders Juul; Y B de Rijke; Michaela F. Hartmann; A Saba; O Hiort; Stefan A. Wudy

Disorders or differences in sex development (DSD) comprise a heterogeneous group of conditions with an atypical sex development. For optimal diagnosis, highly specialised laboratory analyses are required across European countries. Working group 3 of EU COST (European Cooperation in Science and Technology) Action BM 1303 ‘DSDnet’ ‘Harmonisation of Laboratory Assessment’ has developed recommendations on laboratory assessment for DSD regarding the use of technologies and analytes to be investigated. This position paper on steroid hormone analysis in diagnosis and treatment of DSD was compiled by a group of specialists in DSD and/or hormonal analysis, either from participating European countries or international partner countries. The topics discussed comprised analytical methods (immunoassay/mass spectrometry-based methods), matrices (urine/serum/saliva) and harmonisation of laboratory tests. The following positions were agreed upon: support of the appropriate use of immunoassay- and mass spectrometry-based methods for diagnosis and monitoring of DSD. Serum/plasma and urine are established matrices for analysis. Laboratories performing analyses for DSD need to operate within a quality framework and actively engage in harmonisation processes so that results and their interpretation are the same irrespective of the laboratory they are performed in. Participation in activities of peer comparison such as sample exchange or when available subscribing to a relevant external quality assurance program should be achieved. The ultimate aim of the guidelines is the implementation of clinical standards for diagnosis and appropriate treatment of DSD to achieve the best outcome for patients, no matter where patients are investigated or managed.


Clinical Endocrinology | 2008

Transient anomalies in genital appearance in some extremely preterm female infants may be the result of foetal programming causing a surge in LH and the over activation of the pituitary–gonadal axis

Ronda F. Greaves; Rodney W. Hunt; Margaret Zacharin

Aim  Animal studies have linked foetal programming with the development of the polycystic ovarian syndrome, and metabolic syndrome, in adulthood. The objective is to describe the investigation of four extreme‐premature female infants born between 25 and 29 weeks’ gestation with apparent genital abnormalities in association with unusually high androgens and gonadotrophins, to postulate a cause and to raise awareness of pitfalls in assessment of these infants.


Journal of Paediatrics and Child Health | 2004

Genital abnormalities mimicking congenital adrenal hyperplasia in premature infants

Ronda F. Greaves; Shankar Kanumakala; A Read; Margaret Zacharin

Abstract:  Unusual genital appearances in premature infants can be easily mistaken for true ambiguous genitalia, with alarming consequences. The results of blood and urine tests carried out for premature infants can be misleading due to persistence of the foetal zone of the adrenal cortex. More importantly, misdiagnosis is devastating for the parents and adds significantly to their distress. Here, we describe two patients with transient genital abnormalities and abnormal biochemical tests.


Annals of Clinical Biochemistry | 2016

Doping in sport and exercise: anabolic, ergogenic, health and clinical issues

Stephen Bird; Catrin Goebel; Louise M. Burke; Ronda F. Greaves

The use of doping agents is evident within competitive sport in senior and junior age groups, where they are taken by non-elite as well as elite participants. They are also taken in non-sporting contexts by individuals seeking to ‘improve’ their physique through an increase in muscle and/or decrease in fat mass. While attaining accurate data on the prevalence of their use has limitations, studies suggest the illicit use of doping agents by athletes and non-athletes may be 1–5% in the population and greater than 50% in some groups; with the prevalence being higher in males. There is conclusive evidence that some doping agents are anabolic and ergogenic. There is also evidence that the use of doping agents such as anabolic androgenic steroids, growth hormone and other anabolic agents, erythropoietin and stimulants conveys considerable health risks that include, but are not limited to: cardiovascular disease, diabetes, cancer, mental health issues, virilisation in females and the suppression of naturally produced androgens in males. This review will outline the anabolic, ergogenic and health impacts of selected doping agents and methods that may be used in both the sporting and physique development contexts. It also provides a brief tabulated overview of the history of doping and how doping agents may impact upon the analyses of clinical samples.


The Journal of Steroid Biochemistry and Molecular Biology | 2016

A simultaneous quantitative method for vitamins A, D and E in human serum using liquid chromatography-tandem mass spectrometry

Ali A. Albahrani; Victor Rotarou; Peter J. Roche; Ronda F. Greaves

Non-classical roles of fat-soluble vitamins (FSVs) in many pathologies including cancer have been identified. There is also evidence of hormonal interactions between two of these vitamins, A and D. As a result of this enhanced clinical association with disease, translational clinical research and laboratory requests for FSV measurement has significantly increased. However there are still gaps in the analytical methods available for the measurement of these vitamins. This study aimed to develop a method for simultaneous quantification of 25-hydroxyvitamin-D2 (25-OHD2), 25-hydroxyvitamin-D3 (25-OHD3) and its 3-epimer (epi-25-OHD3), retinol and α-tocopherol in human serum using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The procedure was developed and validated across two LC-MS/MS platforms, using commercial calibrators referenced to certified reference materials, controls, and deuterated internal standards. The samples were prepared by liquid-liquid extraction prior to injection and LC separation (using a Pursuit-PFP column) on two Agilent MS/MS systems (6410 and 6490) in electrospray ionisation positive mode with multiple reaction monitoring. Identification and quantification of 25-OHD3 from its 3-epimer as well as 25-OHD2, retinol and α-tocopherol were achieved. The dynamic ranges were 4-160 nmol/L for 25-OHD2 and epi-25-OHD3, 4-200 nmol/L for 25-OHD3, 0.1-4.0μmol/L for retinol and 4-70μmol/L for α-tocopherol with correlation (r(2)) of 0.997-0.998. Based on participation in an external quality assurance program, the overall performance of the simultaneous methods were: imprecision (CV%) and inaccuracy (average bias) 3.0% and 3.2 nmol/L, respectively, for 25-OHD3; 5.0% and 0.04μmol/L, respectively, for retinol; and 4.7% and 0.2μmol/L, respectively, for α-tocopherol. In summary, two simple LC-MS/MS methods were successfully developed and validated for the simultaneous quantification of the three vitamin D metabolites (25-OHD2, 25-OHD3 and 3-epimer of 25-OHD3), vitamin A (retinol) and vitamin E (α-tocopherol) in serum.


BMJ Open | 2015

VITALITY trial: protocol for a randomised controlled trial to establish the role of postnatal vitamin D supplementation in infant immune health

Katrina J. Allen; Mary Panjari; Jennifer J. Koplin; Anne-Louise Ponsonby; Peter Vuillermin; Lyle C. Gurrin; Ronda F. Greaves; Natalie Carvalho; Kim Dalziel; Mimi L.K. Tang; Katherine J. Lee; Melissa Wake; Nigel Curtis; Shyamali C. Dharmage

Introduction Postnatal vitamin D supplementation may be associated with a reduction in IgE-mediated food allergy, lower respiratory tract infections and improved bone health. Countries in the Northern hemisphere recommend universal infant vitamin D supplementation to optimise early vitamin D levels, despite the absence of large trials proving safety or efficacy for any disease outcome. With the aim of determining the clinical and cost-effectiveness of daily vitamin D supplementation in breastfed infants from age 6–8 weeks to 12 months of age, we have started a double-blind, randomised, placebo-controlled trial of daily 400 IU vitamin D supplementation during the first year of life, VITALITY. Methods nd analysis Infants (n=3012) who are fully breastfed and not receiving vitamin D supplementation will be recruited at the time of their first immunisation, from council-led immunisation clinics throughout metropolitan Melbourne, Australia. The primary outcome is challenge-proven food allergy at 12 months of age. Secondary outcomes are food sensitisation (positive skin prick test), number of lower respiratory infections (through hospital linkage), moderately-severe and persistent eczema (by history and examination) and vitamin D deficiency (serum vitamin D <50 nmol/L) at age 12 months. The trial is underway and the first 130 participants have been recruited. Ethics and dissemination The VITALITY study is approved by the Royal Childrens Hospital (RCH) Human Research Ethics Committee (#34168). Outcomes will be disseminated through publication and will be presented at scientific conferences. Trial registration numbers ANZCTR12614000334606 and NCT02112734; pre-results.


Clinical Biochemistry | 2014

A guide to understanding the steroid pathway: new insights and diagnostic implications.

Ronda F. Greaves; Ganesh Jevalikar; Jacqueline K. Hewitt; Margaret Zacharin

Steroid analysis has always been complicated requiring a clear understanding of both the clinical and analytical aspects in order to accurately interpret results. The literature relating to this specialised area spans many decades and the intricacies of the steroid pathway have evolved with time. A number of key changes, including discovery of the alternative androgen pathway, have occurred in the last decade, potentially changing our understanding and approach to investigating disorders of sexual development. Such investigation usually occurs in specialised paediatric centres and although preterm infants represent only a small percentage of the patient population, consideration of the persistence of the foetal adrenal zone is an additional important consideration when undertaking steroid hormone investigations. The recent expanded role of mass spectrometry and molecular diagnostic methods provides significant improvements for accurate steroid quantification and identification of enzyme deficiencies. However analysis of steroids and interpretation of results remain complicated. This review aims to provide an insight into the complexities of steroid measurement in children and offers an updated guide to interpretation, of serum and urine steroids through the presentation of a refined steroid pathway.


Clinical Biochemistry | 2014

Are vitamins A and D important in the development of food allergy and how are they best measured

Rosita Zakariaeeabkoo; Katrina J. Allen; Jennifer J. Koplin; Peter Vuillermin; Ronda F. Greaves

Food allergy has a dramatic impact on a childs (and their familys) quality of life and places a major financial burden on the community. It has been hypothesized that the increase in food allergy may relate to the concordant rise in prevalence of vitamin D insufficiency. More recently a second hypothesis has implicated vitamin A sufficiency in the development of immune tolerance. Together, these hypotheses have prompted investigation into the circulating levels of vitamins A and D in relation to food allergy prevalence. This review aims to examine the relationship between vitamins A and D and food allergy. The first part of this review presents the available epidemiological data which proposes a dramatic increase of food allergy and related anaphylaxis during the last two decades. There is some indirect evidence that variation in food allergy prevalence within countries might be linked with ambient ultra violet radiation exposure and thus potentially with vitamin D levels. Only a few studies to date have directly examined the relationship between measured serum vitamin D levels and either food sensitization or allergy. The significance of vitamin A in food allergy prevalence is only provided through a hypothetical association due to its role in the immune system. The second part of this review discusses the relevant aspects of the analytical methods to assess vitamin A and D levels in children. The primary methods utilized relate to measuring the main circulating forms of vitamins A and D in blood i.e. retinol and 25-hydroxy-vitamin-D3 respectively. Chromatographic separation coupled with mass spectrometric detection is considered the gold standard method for both vitamins. These analytical methods should be fully validated for the use in pediatric populations to ensure they are fit for their clinical purpose.

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Rodney W. Hunt

Royal Children's Hospital

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John Massie

Royal Children's Hospital

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