51
|
Chan YM, Broder-Fingert S, Parachos S, Lapatto R, Au M, Hughes V, Bianco SD, Min L, Plummer L, Cerrato F, De Guillebon A, Wu IH, Wahab F, Dwyer A, Kirsch S, Quinton R, Cheetham T, Ozata M, Ten S, Chanoine JP, Pitteloud N, Martin KA, Schiffmann R, Van der Kamp HJ, Nader S, Hall JE, Kaiser UB, Seminara SB. GnRH-Deficient Phenotypes in Humans and Mice With Heterozygous Variants in KISS1/Kiss1. Obstet Gynecol Surv 2012. [DOI: 10.1097/ogx.0b013e318268d4cb] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
52
|
Pesant MH, Dwyer A, Marques Vidal P, Schneiter P, Giusti V, Tappy L, Pralong FP. The lack of effect of insulin on luteinizing hormone pulsatility in healthy male volunteers provides evidence of a sexual dimorphism in the metabolic regulation of reproductive hormones. Am J Clin Nutr 2012; 96:283-8. [PMID: 22760567 DOI: 10.3945/ajcn.111.030189] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND The activity of the neuroendocrine reproductive axis is closely related to nutritional status. This link is particularly important in healthy women, in whom insulin is a positive signal for the reproductive system. In contrast, very little is known regarding this relation in men. OBJECTIVES This study was designed to evaluate the effect of insulin on the reproductive axis of young male volunteers and to study the effect of short-term hypercaloric feeding on this modulation. DESIGN The activity of the neuroendocrine reproductive axis was characterized by the pattern of endogenous luteinizing hormone (LH) secretion on the basis of frequent blood sampling protocols. The effect of insulin was tested by comparing the LH secretion pattern between a baseline study and a hyperinsulinemic euglycemic clamp. These studies were performed first in subjects fed a controlled isocaloric diet for 6 d (calculated as 1.5 times their resting metabolic rate) then in the same subjects fed a controlled hypercaloric diet in which 30% extra calories were provided as fat and fructose (3 g · kg(-1) · d(-1)) before undergoing identical protocols. Serum gonadotropins, sex steroids, glucose, insulin, ghrelin, and leptin concentrations were assessed, and the HOMA-IR was calculated. RESULTS The LH secretion pattern was not affected by insulin or by hypercaloric feeding. Insulin decreased ghrelin and increased leptin concentrations but had no additional effect of hypercaloric feeding despite significantly lower HOMA-IR indexes. CONCLUSIONS Our data indicate that neither insulin nor short-term hypercaloric feeding has any effect on the activity of the male reproductive axis. They also further support the association between ghrelin and insulin and glucose metabolism. This trial was registered at clinicaltrials.gov as NCT01058681.
Collapse
|
53
|
Chan YM, Broder-Fingert S, Paraschos S, Lapatto R, Au M, Hughes V, Bianco SDC, Min L, Plummer L, Cerrato F, De Guillebon A, Wu IH, Wahab F, Dwyer A, Kirsch S, Quinton R, Cheetham T, Ozata M, Ten S, Chanoine JP, Pitteloud N, Martin KA, Schiffmann R, Van der Kamp HJ, Nader S, Hall JE, Kaiser UB, Seminara SB. GnRH-deficient phenotypes in humans and mice with heterozygous variants in KISS1/Kiss1. J Clin Endocrinol Metab 2011; 96:E1771-81. [PMID: 21880801 PMCID: PMC3205899 DOI: 10.1210/jc.2011-0518] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
CONTEXT KISS1 is a candidate gene for GnRH deficiency. OBJECTIVE Our objective was to identify deleterious mutations in KISS1. PATIENTS AND METHODS DNA sequencing and assessment of the effects of rare sequence variants (RSV) were conducted in 1025 probands with GnRH-deficient conditions. RESULTS Fifteen probands harbored 10 heterozygous RSV in KISS1 seen in less than 1% of control subjects. Of the variants that reside within the mature kisspeptin peptide, p.F117L (but not p.S77I, p.Q82K, p.H90D, or p.P110T) reduces inositol phosphate generation. Of the variants that lie within the coding region but outside the mature peptide, p.G35S and p.C53R (but not p.A129V) are predicted in silico to be deleterious. Of the variants that lie outside the coding region, one (g.1-3659C→T) impairs transcription in vitro, and another (c.1-7C→T) lies within the consensus Kozak sequence. Of five probands tested, four had abnormal baseline LH pulse patterns. In mice, testosterone decreases with heterozygous loss of Kiss1 and Kiss1r alleles (wild-type, 274 ± 99, to double heterozygotes, 69 ± 16 ng/dl; r(2) = 0.13; P = 0.03). Kiss1/Kiss1r double-heterozygote males have shorter anogenital distances (13.0 ± 0.2 vs. 15.6 ± 0.2 mm at P34, P < 0.001), females have longer estrous cycles (7.4 ± 0.2 vs. 5.6 ± 0.2 d, P < 0.01), and mating pairs have decreased litter frequency (0.59 ± 0.09 vs. 0.71 ± 0.06 litters/month, P < 0.04) and size (3.5 ± 0.2 vs. 5.4 ± 0.3 pups/litter, P < 0.001) compared with wild-type mice. CONCLUSIONS Deleterious, heterozygous RSV in KISS1 exist at a low frequency in GnRH-deficient patients as well as in the general population in presumably normal individuals. As in Kiss1(+/-)/Kiss1r(+/-) mice, heterozygous KISS1 variants in humans may work with other genetic and/or environmental factors to cause abnormal reproductive function.
Collapse
|
54
|
Miraoui H, Dwyer A, Pitteloud N. Role of fibroblast growth factor (FGF) signaling in the neuroendocrine control of human reproduction. Mol Cell Endocrinol 2011; 346:37-43. [PMID: 21664428 PMCID: PMC3185130 DOI: 10.1016/j.mce.2011.05.042] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/27/2011] [Indexed: 12/20/2022]
Abstract
Fibroblast growth factor (FGF) signaling is critical for a broad range of developmental processes. In 2003, Fibroblast growth factor receptor 1 (FGFR1) was discovered as a novel locus causing both forms of isolate GnRH Deficiency, Kallmann syndrome [KS with anosmia] and normosmic idiopathic hypogonadotropic hypogonadism [nIHH] eventually accounting for approximately 10% of gonadotropin-releasing hormone (GnRH) deficiency cases. Such cases are characterized by a broad spectrum of reproductive phenotypes from severe congenital forms of GnRH deficiency to reversal of HH. Additionally, the variable expressivity of both reproductive and non-reproductive phenotypes among patients and family members harboring the identical FGFR1 mutations has pointed to a more complex, oligogenic model for GnRH deficiency. Further, reversal of HH in patients carrying FGFR1 mutations suggests potential gene-environment interactions in human GnRH deficiency disorders.
Collapse
|
55
|
Mitchell AL, Dwyer A, Pitteloud N, Quinton R. Genetic basis and variable phenotypic expression of Kallmann syndrome: towards a unifying theory. Trends Endocrinol Metab 2011; 22:249-58. [PMID: 21511493 DOI: 10.1016/j.tem.2011.03.002] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2011] [Revised: 02/09/2011] [Accepted: 03/11/2011] [Indexed: 01/14/2023]
Abstract
Idiopathic hypogonadotropic hypogonadism (IHH) is defined by absent or incomplete puberty and characterised biochemically by low levels of sex steroids, with low or inappropriately normal gonadotropin hormones. IHH is frequently accompanied by non-reproductive abnormalities, most commonly anosmia, which is present in 50-60% of cases and defines Kallmann syndrome. The understanding of IHH has undergone rapid evolution, both in respect of genetics and breadth of phenotype. Once considered in monogenic Mendelian terms, it is now more coherently understood as a complex genetic condition. Oligogenic and complex genetic-environmental interactions have now been identified, with physiological and environmental factors interacting in genetically susceptible individuals to alter the clinical course and phenotype. These potentially link IHH to ancient evolutionary pressures on the ancestral human genome.
Collapse
|
56
|
Yao J, Dwyer A, Summers RM, Mollura DJ. Computer-aided diagnosis of pulmonary infections using texture analysis and support vector machine classification. Acad Radiol 2011; 18:306-14. [PMID: 21295734 DOI: 10.1016/j.acra.2010.11.013] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2010] [Revised: 11/08/2010] [Accepted: 11/09/2010] [Indexed: 01/07/2023]
Abstract
RATIONALE AND OBJECTIVES The purpose of this study was to develop and test a computer-assisted detection method for the identification and measurement of pulmonary abnormalities on chest computed tomographic (CT) imaging in cases of infection, such as novel H1N1 influenza. The method developed could be a potentially useful tool for classifying and quantifying pulmonary infectious disease on CT imaging. MATERIALS AND METHODS Forty chest CT examinations were studied using texture analysis and support vector machine classification to differentiate normal from abnormal lung regions on CT imaging, including 10 patients with immunohistochemistry-proven infection, 10 normal controls, and 20 patients with fibrosis. RESULTS Statistically significant differences in the receiver-operating characteristic curves for detecting abnormal regions in H1N1 infection were obtained between normal lung and regions of fibrosis, with significant differences in texture features of different infections. These differences enabled the quantification of abnormal lung volumes on CT imaging. CONCLUSION Texture analysis and support vector machine classification can distinguish between areas of abnormality in acute infection and areas of chronic fibrosis, differentiate lesions having consolidative and ground-glass appearances, and quantify those texture features to increase the precision of CT scoring as a potential tool for measuring disease progression and severity.
Collapse
|
57
|
LoGiudice DC, Smith K, Atkinson D, Dwyer A, Lautenschlager N, Almeida OA, Flicker L. Preliminary evaluation of the prevalence of falls, pain and urinary incontinence in remote living Indigenous Australians over the age of 45 years. Intern Med J 2010; 42:e102-7. [DOI: 10.1111/j.1445-5994.2010.02332.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
58
|
Sykiotis GP, Hoang XH, Avbelj M, Hayes FJ, Thambundit A, Dwyer A, Au M, Plummer L, Crowley WF, Pitteloud N. Congenital idiopathic hypogonadotropic hypogonadism: evidence of defects in the hypothalamus, pituitary, and testes. J Clin Endocrinol Metab 2010; 95:3019-27. [PMID: 20382682 PMCID: PMC2902061 DOI: 10.1210/jc.2009-2582] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Idiopathic hypogonadotropic hypogonadism (IHH) with normal smell (normosmic IHH) or anosmia (Kallmann syndrome) is associated with defects in the production or action of GnRH. Accordingly, most IHH patients respond to physiological pulsatile GnRH replacement by normalizing serum LH, FSH, and testosterone (T) levels and achieving gametogenesis; some patients, however, show atypical responses. Interestingly, several IHH-associated genes are expressed in multiple compartments of the hypothalamic-pituitary-gonadal axis. OBJECTIVE The aim of the study was to investigate whether the clinical, biochemical, or genetic characteristics of IHH men with atypical responses to GnRH indicate alternative or additional defects in the hypothalamic-pituitary-gonadal axis. SUBJECTS We studied 90 IHH men undergoing long-term pulsatile GnRH treatment over 30 yr. DESIGN AND SETTING We conducted a retrospective study of response to GnRH at a Clinical Research Center. INTERVENTIONS Physiological regimens of pulsatile s.c. GnRH were administered for at least 12 months. Dose-response studies using i.v. GnRH pulses assessed the pituitary LH response. MAIN OUTCOME MEASURES We measured serum T, LH, FSH, and inhibin B levels, sperm in ejaculate, and determined the sequence of IHH-associated genes. RESULTS Twenty-six percent of subjects displayed atypical responses to GnRH: 1) 10 remained hypogonadotropic and hypogonadal, demonstrating pituitary and testicular defects; 2) eight achieved spermatogenesis and normal T but only with hypergonadotropism, indicating impaired testicular responsiveness to gonadotropins; and 3) five remained azoospermic despite achieving adult testicular volumes and normal hormonal profiles, suggesting primary defects in spermatogenesis. Mutations were identified only in KAL1 across groups. CONCLUSION In addition to hypothalamic GnRH deficiency, IHH men can have primary pituitary and/or testicular defects, which are unmasked by GnRH replacement.
Collapse
|
59
|
Balasubramanian R, Dwyer A, Seminara SB, Pitteloud N, Kaiser UB, Crowley WF. Human GnRH deficiency: a unique disease model to unravel the ontogeny of GnRH neurons. Neuroendocrinology 2010; 92:81-99. [PMID: 20606386 PMCID: PMC3214927 DOI: 10.1159/000314193] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2010] [Accepted: 04/21/2010] [Indexed: 11/19/2022]
Abstract
Evolutionary survival of a species is largely a function of its reproductive fitness. In mammals, a sparsely populated and widely dispersed network of hypothalamic neurons, the gonadotropin-releasing hormone (GnRH) neurons, serve as the pilot light of reproduction via coordinated secretion of GnRH. Since it first description, human GnRH deficiency has been recognized both clinically and genetically as a heterogeneous disease. A spectrum of different reproductive phenotypes comprised of congenital GnRH deficiency with anosmia (Kallmann syndrome), congenital GnRH deficiency with normal olfaction (normosmic idiopathic hypogonadotropic hypogonadism), and adult-onset hypogonadotropic hypogonadism has been described. In the last two decades, several genes and pathways which govern GnRH ontogeny have been discovered by studying humans with GnRH deficiency. More importantly, detailed study of these patients has highlighted the emerging theme of oligogenicity and genotypic synergism, and also expanded the phenotypic diversity with the documentation of reversal of GnRH deficiency later in adulthood in some patients. The underlying genetic defect has also helped understand the associated nonreproductive phenotypes seen in some of these patients. These insights now provide practicing clinicians with targeted genetic diagnostic strategies and also impact on clinical management.
Collapse
MESH Headings
- Animals
- Extracellular Matrix Proteins/deficiency
- Extracellular Matrix Proteins/genetics
- Female
- Fibroblast Growth Factors/genetics
- Fibroblast Growth Factors/metabolism
- Gastrointestinal Hormones/genetics
- Gastrointestinal Hormones/metabolism
- Gonadotropin-Releasing Hormone/deficiency
- Gonadotropin-Releasing Hormone/genetics
- Humans
- Hypogonadism/genetics
- Hypothalamus/growth & development
- Kallmann Syndrome/genetics
- Male
- Mice
- Nerve Tissue Proteins/deficiency
- Nerve Tissue Proteins/genetics
- Neuropeptides/genetics
- Neuropeptides/metabolism
- Olfaction Disorders/genetics
- Phenotype
- Receptors, G-Protein-Coupled/deficiency
- Receptors, G-Protein-Coupled/genetics
- Receptors, G-Protein-Coupled/metabolism
- Receptors, Kisspeptin-1
- Receptors, LHRH/genetics
- Receptors, LHRH/metabolism
- Receptors, Neurokinin-3/genetics
- Receptors, Neurokinin-3/metabolism
- Receptors, Peptide/genetics
- Receptors, Peptide/metabolism
- Transcription Factors/genetics
- Transcription Factors/metabolism
Collapse
|
60
|
Raivio T, Sidis Y, Plummer L, Chen H, Ma J, Mukherjee A, Jacobson-Dickman E, Quinton R, Van Vliet G, Lavoie H, Hughes VA, Dwyer A, Hayes FJ, Xu S, Sparks S, Kaiser UB, Mohammadi M, Pitteloud N. Frequency of Impaired Fibroblast Growth Factor Receptor 1 Signaling as a Cause of Normosmic Idiopathic Hypogonadotropic Hypogonadism. Mol Endocrinol 2009. [DOI: 10.1210/mend.23.12.9994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
ABSTRACT
Context
FGFR1 mutations have been identified in about 10% of patients with Kallmann syndrome. Recently cases of idiopathic hypogonadotropic hypogonadism (IHH) with a normal sense of smell (nIHH) have been reported.
Aims
The objective of the study was to define the frequency of FGFR1 mutations in a large cohort of nIHH, delineate the spectrum of reproductive phenotypes, assess functionality of the FGFR1 mutant alleles in vitro, and investigate genotype-phenotype relationships.
Design
FGFR1 sequencing of 134 well-characterized nIHH patients (112 men and 22 women) and 270 healthy controls was performed. The impact of the identified mutations on FGFR1 function was assessed using structural prediction and in vitro studies.
Results
Nine nIHH subjects (five males and four females; 7%) harbor a heterozygous mutation in FGFR1 and exhibit a wide spectrum of pubertal development, ranging from absent puberty to reversal of IHH in both sexes. All mutations impair receptor function. The Y99C, Y228D, and I239T mutants impair the tertiary folding, resulting in incomplete glycosylation and reduced cell surface expression. The R250Q mutant reduces receptor affinity for FGF. The K618N, A671P, and Q680X mutants impair tyrosine kinase activity. However, the degree of functional impairment of the mutant receptors did not always correlate with the reproductive phenotype, and variable expressivity of the disease was noted within family members carrying the same FGFR1 mutation. These discrepancies were partially explained by additional mutations in known IHH loci.
Conclusions
Loss-of-function mutations in FGFR1 underlie 7% of nIHH with different degrees of impairment in vitro. These mutations act in concert with other gene defects in several cases, consistent with oligogenicity.
Collapse
|
61
|
Raivio T, Sidis Y, Plummer L, Chen H, Ma J, Mukherjee A, Jacobson-Dickman E, Quinton R, Van Vliet G, Lavoie H, Hughes VA, Dwyer A, Hayes FJ, Xu S, Sparks S, Kaiser UB, Mohammadi M, Pitteloud N. Frequency of Impaired Fibroblast Growth Factor Receptor 1 Signaling as a Cause of Normosmic Idiopathic Hypogonadotropic Hypogonadism. Endocr Rev 2009; 30:934. [PMID: 28199515 DOI: 10.1210/edrv.30.7.9981] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
62
|
Raivio T, Sidis Y, Plummer L, Chen H, Ma J, Mukherjee A, Jacobson-Dickman E, Quinton R, Van Vliet G, Lavoie H, Hughes VA, Dwyer A, Hayes FJ, Xu S, Sparks S, Kaiser UB, Mohammadi M, Pitteloud N. Impaired fibroblast growth factor receptor 1 signaling as a cause of normosmic idiopathic hypogonadotropic hypogonadism. J Clin Endocrinol Metab 2009; 94:4380-90. [PMID: 19820032 PMCID: PMC2775659 DOI: 10.1210/jc.2009-0179] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
CONTEXT FGFR1 mutations have been identified in about 10% of patients with Kallmann syndrome. Recently cases of idiopathic hypogonadotropic hypogonadism (IHH) with a normal sense of smell (nIHH) have been reported. AIMS The objective of the study was to define the frequency of FGFR1 mutations in a large cohort of nIHH, delineate the spectrum of reproductive phenotypes, assess functionality of the FGFR1 mutant alleles in vitro, and investigate genotype-phenotype relationships. DESIGN FGFR1 sequencing of 134 well-characterized nIHH patients (112 men and 22 women) and 270 healthy controls was performed. The impact of the identified mutations on FGFR1 function was assessed using structural prediction and in vitro studies. RESULTS Nine nIHH subjects (five males and four females; 7%) harbor a heterozygous mutation in FGFR1 and exhibit a wide spectrum of pubertal development, ranging from absent puberty to reversal of IHH in both sexes. All mutations impair receptor function. The Y99C, Y228D, and I239T mutants impair the tertiary folding, resulting in incomplete glycosylation and reduced cell surface expression. The R250Q mutant reduces receptor affinity for FGF. The K618N, A671P, and Q680X mutants impair tyrosine kinase activity. However, the degree of functional impairment of the mutant receptors did not always correlate with the reproductive phenotype, and variable expressivity of the disease was noted within family members carrying the same FGFR1 mutation. These discrepancies were partially explained by additional mutations in known IHH loci. CONCLUSIONS Loss-of-function mutations in FGFR1 underlie 7% of nIHH with different degrees of impairment in vitro. These mutations act in concert with other gene defects in several cases, consistent with oligogenicity.
Collapse
|
63
|
Huberty JL, Vener J, Waltman N, Ott C, Twiss J, Gross G, McGuire R, Dwyer A. Development of an Instrument to Measure Adherence to Strength Training in Postmenopausal Breast Cancer Survivors. Oncol Nurs Forum 2009; 36:E266-73. [DOI: 10.1188/09.onf.e266-e273] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
64
|
Rico-Pecero J, Dwyer A. Fractura triplana de tobillo relacionada con fractura tibial homolateral en un adolescente. Caso clínico. Rev Esp Cir Ortop Traumatol (Engl Ed) 2009. [DOI: 10.1016/j.recot.2008.10.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
|
65
|
Abraham J, Edgerly M, Wilson R, Chen C, Rutt A, Bakke S, Robey R, Dwyer A, Goldspiel B, Balis F, Van Tellingen O, Bates SE, Fojo T. A phase I study of the P-glycoprotein antagonist tariquidar in combination with vinorelbine. Clin Cancer Res 2009; 15:3574-82. [PMID: 19417029 DOI: 10.1158/1078-0432.ccr-08-0938] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE P-glycoprotein (Pgp) antagonists have had unpredictable pharmacokinetic interactions requiring reductions of chemotherapy. We report a phase I study using tariquidar (XR9576), a potent Pgp antagonist, in combination with vinorelbine. EXPERIMENTAL DESIGN Patients first received tariquidar alone to assess effects on the accumulation of (99m)Tc-sestamibi in tumor and normal organs and rhodamine efflux from CD56+ mononuclear cells. In the first cycle, vinorelbine pharmacokinetics was monitored after the day 1 and 8 doses without or with tariquidar. In subsequent cycles, vinorelbine was administered with tariquidar. Tariquidar pharmacokinetics was studied alone and with vinorelbine. RESULTS Twenty-six patients were enrolled. Vinorelbine 20 mg/m(2) on day 1 and 8 was identified as the maximum tolerated dose (neutropenia). Nonhematologic grade 3/4 toxicities in 77 cycles included the following: abdominal pain (4 cycles), anorexia (2), constipation (2), fatigue (3), myalgia (2), pain (4) and dehydration, depression, diarrhea, ileus, nausea, and vomiting, (all once). A 150-mg dose of tariquidar: (1) reduced liver (99m)Tc-sestamibi clearance consistent with inhibition of liver Pgp; (2) increased (99m)Tc-sestamibi retention in a majority of tumor masses visible by (99m)Tc-sestamibi; and (3) blocked Pgp-mediated rhodamine efflux from CD56+ cells over the 48 hours examined. Tariquidar had no effects on vinorelbine pharmacokinetics. Vinorelbine had no effect on tariquidar pharmacokinetics. One patient with breast cancer had a minor response, and one with renal carcinoma had a partial remission. CONCLUSIONS Tariquidar is a potent Pgp antagonist, without significant side effects and much less pharmacokinetic interaction than previous Pgp antagonists. Tariquidar offers the potential to increase drug exposure in drug-resistant cancers.
Collapse
|
66
|
Yao J, Avila N, Dwyer A, Taveira-Dasilva AM, Hathaway OM, Moss J. Computer-Aided Grading of Lymphangioleiomyomatosis (LAM) using HRCT. PROCEEDINGS OF THE ... IAPR INTERNATIONAL CONFERENCE ON PATTERN RECOGNITION. INTERNATIONAL CONFERENCE ON PATTERN RECOGNITION 2008; 2008:1-4. [PMID: 21625320 DOI: 10.1109/icpr.2008.4760991] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Lymphangioleiomyomatosis (LAM) is a multisystem disorder associated with proliferation of smooth muscle-like cells, which leads to destruction of lung parenchyma. Subjective grading of LAM on HRCT is imprecise and can be arduous especially in cases with severe involvement. We propose a computer-aided evaluation system that grades LAM involvement based on analysis of lung texture patterns. A committee of support vector machines is employed for classification. The system was tested on 36 patients. The computer grade demonstrates good correlation with subjective radiologist grade (R=0.91, p<0.0001) and pulmonary functional tests (R=0.85, p<0.0001). The grade also provides precise progression assessment of disease over time.
Collapse
|
67
|
Smith K, Flicker L, Lautenschlager NT, Almeida OP, Atkinson D, Dwyer A, LoGiudice D. High prevalence of dementia and cognitive impairment in Indigenous Australians. Neurology 2008; 71:1470-3. [DOI: 10.1212/01.wnl.0000320508.11013.4f] [Citation(s) in RCA: 101] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
|
68
|
Falardeau J, Chung WC, Beenken A, Raivio T, Plummer L, Sidis Y, Jacobson-Dickman EE, Eliseenkova AV, Ma J, Dwyer A, Quinton R, Na S, Hall JE, Huot C, Alois N, Pearce SH, Cole LW, Hughes V, Mohammadi M, Tsai P, Pitteloud N. Decreased FGF8 signaling causes deficiency of gonadotropin-releasing hormone in humans and mice. J Clin Invest 2008; 118:2822-31. [PMID: 18596921 PMCID: PMC2441855 DOI: 10.1172/jci34538] [Citation(s) in RCA: 252] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2007] [Accepted: 05/21/2008] [Indexed: 12/18/2022] Open
Abstract
Idiopathic hypogonadotropic hypogonadism (IHH) with anosmia (Kallmann syndrome; KS) or with a normal sense of smell (normosmic IHH; nIHH) are heterogeneous genetic disorders associated with deficiency of gonadotropin-releasing hormone (GnRH). While loss-of-function mutations in FGF receptor 1 (FGFR1) cause human GnRH deficiency, to date no specific ligand for FGFR1 has been identified in GnRH neuron ontogeny. Using a candidate gene approach, we identified 6 missense mutations in FGF8 in IHH probands with variable olfactory phenotypes. These patients exhibited varied degrees of GnRH deficiency, including the rare adult-onset form of hypogonadotropic hypogonadism. Four mutations affected all 4 FGF8 splice isoforms (FGF8a, FGF8b, FGF8e, and FGF8f), while 2 mutations affected FGF8e and FGF8f isoforms only. The mutant FGF8b and FGF8f ligands exhibited decreased biological activity in vitro. Furthermore, mice homozygous for a hypomorphic Fgf8 allele lacked GnRH neurons in the hypothalamus, while heterozygous mice showed substantial decreases in the number of GnRH neurons and hypothalamic GnRH peptide concentration. In conclusion, we identified FGF8 as a gene implicated in GnRH deficiency in both humans and mice and demonstrated an exquisite sensitivity of GnRH neuron development to reductions in FGF8 signaling.
Collapse
|
69
|
Raivio T, Falardeau J, Dwyer A, Quinton R, Hayes FJ, Hughes VA, Cole LW, Pearce SH, Lee H, Boepple P, Crowley WF, Pitteloud N. Reversal of idiopathic hypogonadotropic hypogonadism. N Engl J Med 2007; 357:863-73. [PMID: 17761590 DOI: 10.1056/nejmoa066494] [Citation(s) in RCA: 304] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Idiopathic hypogonadotropic hypogonadism, which may be associated with anosmia (the Kallmann syndrome) or with a normal sense of smell, is a treatable form of male infertility caused by a congenital defect in the secretion or action of gonadotropin-releasing hormone (GnRH). Patients have absent or incomplete sexual maturation by the age of 18. Idiopathic hypogonadotropic hypogonadism was previously thought to require lifelong therapy. We describe 15 men in whom reversal of idiopathic hypogonadotropic hypogonadism was sustained after discontinuation of hormonal therapy. METHODS We defined the sustained reversal of idiopathic hypogonadotropic hypogonadism as the presence of normal adult testosterone levels after hormonal therapy was discontinued. RESULTS Ten sustained reversals were identified retrospectively. Five sustained reversals were identified prospectively among 50 men with idiopathic hypogonadotropic hypogonadism after a mean (+/-SD) duration of treatment interruption of 6+/-3 weeks. Of the 15 men who had a sustained reversal, 4 had anosmia. At initial evaluation, 6 men had absent puberty, 9 had partial puberty, and all had abnormal secretion of GnRH-induced luteinizing hormone. All 15 men had received previous hormonal therapy to induce virilization, fertility, or both. Among those whose hypogonadism was reversed, the mean serum level of endogenous testosterone increased from 55+/-29 ng per deciliter (1.9+/-1.0 nmol per liter) to 386+/-91 ng per deciliter (13.4+/-3.2 nmol per liter, P<0.001), the luteinizing hormone level increased from 2.7+/-2.0 to 8.5+/-4.6 IU per liter (P<0.001), the level of follicle-stimulating hormone increased from 2.5+/-1.7 to 9.5+/-12.2 IU per liter (P<0.01), and testicular volume increased from 8+/-5 to 16+/-7 ml (P<0.001). Pulsatile luteinizing hormone secretion and spermatogenesis were documented. CONCLUSIONS Sustained reversal of normosmic idiopathic hypogonadotropic hypogonadism and the Kallmann syndrome was noted after discontinuation of treatment in about 10% of patients with either absent or partial puberty. Therefore, brief discontinuation of hormonal therapy to assess reversibility of hypogonadotropic hypogonadism is reasonable. (ClinicalTrials.gov number, NCT00392756 [ClinicalTrials.gov].).
Collapse
|
70
|
Taylor CG, Tickle W, Dwyer A. Radiometric studies of mercury loss from fungicidal paints. II. Comparison of three phenyl mercury compounds. ACTA ACUST UNITED AC 2007. [DOI: 10.1002/jctb.5010190102] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
71
|
Hill SC, Namde M, Dwyer A, Poznanski A, Canna S, Goldbach-Mansky R. Arthropathy of neonatal onset multisystem inflammatory disease (NOMID/CINCA). Pediatr Radiol 2007; 37:145-52. [PMID: 17136361 DOI: 10.1007/s00247-006-0358-0] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2006] [Revised: 10/17/2006] [Accepted: 10/25/2006] [Indexed: 12/11/2022]
Abstract
BACKGROUND Neonatal onset multisystem inflammatory disease (NOMID), an autoinflammatory disease, is characterized by fever, chronic urticarial rash, CNS manifestations, and arthropathy. Approximately 50% of patients with NOMID have de novo missense mutations in CIAS1, which is associated with modulation of the IL-1b and apoptotic pathways. Approximately 60% of NOMID patients have prominent arthropathy, most commonly involving the knees, the cause of which remains poorly understood. OBJECTIVE To more fully describe the findings of NOMID arthropathy on MRI and radiography and to provide a better understanding of the origin of the bony lesions. MATERIALS AND METHODS We imaged 20 patients with NOMID to further investigate NOMID-associated bony lesions. RESULTS Bony abnormalities were seen in the knees of 11/20 patients. The knee findings included enlarged, deformed femora and patellae in all and tibiae in the majority, without evidence of synovitis. Some patients had other joint involvement. Most had short stature and valgus or varus knee deformities. No association was noted between bony abnormalities and CIAS1 mutations. The abnormalities appeared to be the result of a mass-producing process. The resulting heterogeneously calcified masses appeared to originate in the physis and deformed the adjacent metaphysis and epiphysis. CONCLUSION These findings suggest that the arthropathy of NOMID is the result of abnormal endochondral bone growth. Further investigation is needed to determine whether this deformity is triggered by inflammation early in development or by CIAS1 mutations causing abnormal chondrocyte apoptosis.
Collapse
|
72
|
Pitteloud N, Quinton R, Pearce S, Raivio T, Acierno J, Dwyer A, Plummer L, Hughes V, Seminara S, Cheng YZ, Li WP, Maccoll G, Eliseenkova AV, Olsen SK, Ibrahimi OA, Hayes FJ, Boepple P, Hall JE, Bouloux P, Mohammadi M, Crowley W. Digenic mutations account for variable phenotypes in idiopathic hypogonadotropic hypogonadism. J Clin Invest 2007; 117:457-63. [PMID: 17235395 PMCID: PMC1765517 DOI: 10.1172/jci29884] [Citation(s) in RCA: 265] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2006] [Accepted: 11/27/2006] [Indexed: 11/17/2022] Open
Abstract
Idiopathic hypogonadotropic hypogonadism (IHH) due to defects of gonadotropin-releasing hormone (GnRH) secretion and/or action is a developmental disorder of sexual maturation. To date, several single-gene defects have been implicated in the pathogenesis of IHH. However, significant inter- and intrafamilial variability and apparent incomplete penetrance in familial cases of IHH are difficult to reconcile with the model of a single-gene defect. We therefore hypothesized that mutations at different IHH loci interact in some families to modify their phenotypes. To address this issue, we studied 2 families, one with Kallmann syndrome (IHH and anosmia) and another with normosmic IHH, in which a single-gene defect had been identified: a heterozygous FGF receptor 1 (FGFR1) mutation in pedigree 1 and a compound heterozygous gonadotropin-releasing hormone receptor (GNRHR) mutation in pedigree 2, both of which varied markedly in expressivity within and across families. Further candidate gene screening revealed a second heterozygous deletion in the nasal embryonic LHRH factor (NELF) gene in pedigree 1 and an additional heterozygous FGFR1 mutation in pedigree 2 that accounted for the considerable phenotypic variability. Therefore, 2 different gene defects can synergize to produce a more severe phenotype in IHH families than either alone. This genetic model could account for some phenotypic heterogeneity seen in GnRH deficiency.
Collapse
MESH Headings
- Adult
- Amino Acid Sequence
- Base Sequence
- Conserved Sequence
- DNA/genetics
- Female
- Fibroblast Growth Factor 8/metabolism
- Genotype
- Gonadotropin-Releasing Hormone/deficiency
- Heterozygote
- Humans
- Hypogonadism/etiology
- Hypogonadism/genetics
- Hypogonadism/metabolism
- Kallmann Syndrome/genetics
- Male
- Models, Genetic
- Models, Molecular
- Molecular Sequence Data
- Mutation
- Pedigree
- Phenotype
- Receptor, Fibroblast Growth Factor, Type 1/chemistry
- Receptor, Fibroblast Growth Factor, Type 1/genetics
- Receptor, Fibroblast Growth Factor, Type 1/metabolism
- Receptors, LHRH/genetics
- Sequence Deletion
- Sequence Homology, Amino Acid
- Transcription Factors/genetics
Collapse
|
73
|
Chung T, Sindone A, Foo F, Dwyer A, Paoloni R, Janu MR, Wong H, Hall J, Freedman SB. Influence of history of heart failure on diagnostic performance and utility of B-type natriuretic peptide testing for acute dyspnea in the emergency department. Am Heart J 2006; 152:949-55. [PMID: 17070166 DOI: 10.1016/j.ahj.2006.05.020] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2005] [Accepted: 05/27/2006] [Indexed: 10/24/2022]
Abstract
BACKGROUND The aim of this study was to assess the impact of a history of heart failure (HF) on emergency department (ED) B-type natriuretic peptide (BNP) testing and impact of feedback of BNP level to ED physicians. METHODS Admission BNP was measured in 143 patients (mean age 79 +/- 10 years) presenting to the ED with dyspnea. Emergency department physicians scored probability of HF as cause of dyspnea and categorized cause of dyspnea. An independent cardiologist determined cause of dyspnea after chart review. In 83 patients, ED physicians rescored and reclassified patients after BNP measurement and evaluated test utility. RESULTS The area under the receiver operating characteristic curve for BNP diagnosis of HF cause of dyspnea was significantly worse in patients with history of HF than those without (0.74 vs 0.94, P < .01) and in those with left ventricular ejection fraction <50% (0.64 vs 0.87, P < .05). A BNP cut point of 100 pg/mL had 100% sensitivity but only 41% specificity for diagnosing acute HF, whereas a cut point of 400 pg/mL had 87% sensitivity and 76% specificity. Emergency department physicians rated BNP useful in 64% of patients, and diagnostic uncertainty was reduced from 53% to 25% (P < .001). CONCLUSION B-type natriuretic peptide test performance for diagnosis of dyspnea cause is significantly reduced in patients with a history of HF and must be taken into consideration in the evaluation of such patients in the ED.
Collapse
|
74
|
Cerrato F, Shagoury J, Kralickova M, Dwyer A, Falardeau J, Ozata M, Van Vliet G, Bouloux P, Hall JE, Hayes FJ, Pitteloud N, Martin KA, Welt C, Seminara SB. Coding sequence analysis of GNRHR and GPR54 in patients with congenital and adult-onset forms of hypogonadotropic hypogonadism. Eur J Endocrinol 2006; 155 Suppl 1:S3-S10. [PMID: 17074994 DOI: 10.1530/eje.1.02235] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE To determine the frequency of rare nucleotide variants in GNRHR and GPR54 in a large cohort of probands (n = 166) with normosmic idiopathic hypogonadotropic hypogonadism (nIHH), characterized by mode of inheritance, testicular volume, and presence or absence of endogenous LH pulsations. METHODS Whenever possible, probands answered detailed questionnaires, underwent full physical exams, and underwent q 10-min frequent blood sampling for LH. Exons segments for GNRHR and GPR54 were screened for mutations. Nucleotide changes were identified as rare variants if they occurred at less than 1% frequency in an ethnically matched control population. RESULTS Sixty-two percent of male probands were classified as sporadic, meaning that no other family members had delayed puberty or nIHH. In contrast, 61% of female probands were from familial pedigrees, with either autosomal dominant or autosomal recessive inheritance. Patients displayed a broad spectrum of disease severity based on testicular size and endogenous LH pulsations. Twenty-four rare variants were identified in GNRHR (within 15 probands) and seven rare variants in GPR54 (within five probands). CONCLUSIONS Rare variants in GNRHR are more common than GPR54 in a nIHH population.
Collapse
|
75
|
Kumar PA, Pitteloud N, Andrews PAM, Dwyer A, Hayes F, Crowley WF, Dym M. Testis morphology in patients with idiopathic hypogonadotropic hypogonadism. Hum Reprod 2006; 21:1033-40. [PMID: 16396935 DOI: 10.1093/humrep/dei444] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Adult patients with idiopathic hypogonadotropic hypogonadism (IHH) typically present with absent puberty and therefore have prepubertal testes. IHH is recognized as one of the few curable causes of male infertility and is often effectively treated with either gonadotropins or pulsatile GnRH therapy. The objective of this study was to determine the structure of the testis prior to initiation of treatment. METHODS AND RESULTS Eight adult IHH patients with prepubertal testes (<4 ml), with no previous gonadotropin therapy and with no history of cryptorchidism underwent open bilateral testicular biopsy prior to the initiation of hormonal treatment. The testes of all patients showed seminiferous cords separated by interstitium composed of blood vessels, connective tissue cells and collagen fibres but typical adult Leydig cells were absent. The cords contained only Sertoli cells and early type A spermatogonia. The spermatogonia mostly resided in the centre of the cords and were often large, typical of gonocytes. Sertoli cells appeared immature with ovoid nuclei devoid of infoldings and cytoplasm that lacked polarity. Tight junctional complexes commonly found connecting adult Sertoli cells were lacking. CONCLUSIONS These results demonstrate that the immature testes from patients with the severe form of IHH possess early spermatogonia that could possibly reinitiate spermatogenesis with appropriate hormone stimulation. Therefore, the immature testis of this IHH subset resembles those of prepubertal boys and may provide important biologic and genetic insights into testicular development.
Collapse
|