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1.
Urogynecology (Phila) ; 28(11): 786-792, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36288118

RESUMO

IMPORTANCE: The pathophysiology of interstitial cystitis/bladder pain syndrome (IC/BPS) is imperfectly understood. Recent studies reported that small-fiber polyneuropathy (SFPN) is common in fibromyalgia, a condition commonly comorbid with IC/BPS. OBJECTIVE: The objective of this study was to determine the prevalence of SFPN in a large cohort of IC/BPS patients. METHODS: Adults diagnosed with IC/BPS scheduled to undergo either therapeutic hydrodistention (n = 97) or cystectomy with urinary diversion (n = 3) were prospectively recruited to this study. A skin biopsy obtained from the lower leg was used for intraepidermal nerve fiber density measurement. Small-fiber polyneuropathy (+/-) status was determined by comparing linear intraepidermal nerve fiber density (fibers/mm2) with normative reference values. Demographic information, medical history, and diagnoses for 14 conditions (both urologic and nonurologic) known to co-occur with IC/BPS were documented from self-report and electronic medical record. RESULTS: In this large cohort of patients with IC/BPS, 31% (31/100) were positive for SFPN. Intraepidermal nerve fiber density was below the median for age and sex in 81% (81/100) of patients. Approximately one-third (31%) of SFPN+ patients reported co-occurring chronic fatigue syndrome, compared with 10.6% of the SFPN- group (P = 0.034). Small-fiber polyneuropathy-positive patients reported significantly fewer allergies than SFPN- patients (37.9% vs 60.6%; P = 0.047). There were no significant differences in bladder capacity or Hunner lesion status between the SFPN+ and SFPN- subgroups. CONCLUSIONS: Small-fiber polyneuropathy is a common finding in patients with IC/BPS, and SFPN status is significantly correlated with co-occurring chronic fatigue syndrome and negatively correlated with the presence of allergies in this population.


Assuntos
Cistite Intersticial , Síndrome de Fadiga Crônica , Fibromialgia , Hipersensibilidade , Polineuropatias , Adulto , Humanos , Cistite Intersticial/epidemiologia , Síndrome de Fadiga Crônica/complicações , Polineuropatias/epidemiologia , Fibromialgia/complicações , Hipersensibilidade/complicações
2.
Drug Test Anal ; 7(9): 745-55, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25645199

RESUMO

The GH-2000 and GH-2004 projects have developed a method for detecting GH misuse based on measuring insulin-like growth factor-I (IGF-I) and the amino-terminal pro-peptide of type III collagen (P-III-NP). The objectives were to analyze more samples from elite athletes to improve the reliability of the decision limit estimates, to evaluate whether the existing decision limits needed revision, and to validate further non-radioisotopic assays for these markers. The study included 998 male and 931 female elite athletes. Blood samples were collected according to World Anti-Doping Agency (WADA) guidelines at various sporting events including the 2011 International Association of Athletics Federations (IAAF) World Athletics Championships in Daegu, South Korea. IGF-I was measured by the Immunotech A15729 IGF-I IRMA, the Immunodiagnostic Systems iSYS IGF-I assay and a recently developed mass spectrometry (LC-MS/MS) method. P-III-NP was measured by the Cisbio RIA-gnost P-III-P, Orion UniQ™ PIIINP RIA and Siemens ADVIA Centaur P-III-NP assays. The GH-2000 score decision limits were developed using existing statistical techniques. Decision limits were determined using a specificity of 99.99% and an allowance for uncertainty because of the finite sample size. The revised Immunotech IGF-I - Orion P-III-NP assay combination decision limit did not change significantly following the addition of the new samples. The new decision limits are applied to currently available non-radioisotopic assays to measure IGF-I and P-III-NP in elite athletes, which should allow wider flexibility to implement the GH-2000 marker test for GH misuse while providing some resilience against manufacturer withdrawal or change of assays.


Assuntos
Hormônio do Crescimento Humano/sangue , Fator de Crescimento Insulin-Like I/análise , Fragmentos de Peptídeos/sangue , Pró-Colágeno/sangue , Detecção do Abuso de Substâncias/métodos , Adolescente , Adulto , Atletas , Criança , Dopagem Esportivo , Feminino , Humanos , Imunoensaio/métodos , Limite de Detecção , Masculino , Espectrometria de Massas em Tandem/métodos , Adulto Jovem
3.
Ann Oncol ; 26(2): 354-62, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25467017

RESUMO

BACKGROUND: Continuation or 'switch' maintenance therapy is commonly used in patients with advancd non-small-cell lung cancer (NSCLC). Here, we evaluated the efficacy of the telomerase inhibitor, imetelstat, as switch maintenance therapy in patients with advanced NSCLC. PATIENTS AND METHODS: The primary end point of this open-label, randomized phase II study was progression-free survival (PFS). Patients with non-progressive, advanced NSCLC after platinum-based doublet (first-line) chemotherapy (with or without bevacizumab), any histology, with Eastern Cooperative Oncology Group performance status 0-1 were eligible. Randomization was 2 : 1 in favor of imetelstat, administered at 9.4 mg/kg on days 1 and 8 of a 21-day cycle, or observation. Telomere length (TL) biomarker exploratory analysis was carried out in tumor tissue by quantitative PCR (qPCR) and telomerase fluorescence in situ hybridization. RESULTS: Of 116 patients enrolled, 114 were evaluable. Grade 3/4 neutropenia and thrombocytopenia were more frequent with imetelstat. Median PFS was 2.8 and 2.6 months for imetelstat-treated versus control [hazard ratio (HR) = 0.844; 95% CI 0.54-1.31; P = 0.446]. Median survival time favored imetelstat (14.3 versus 11.5 months), although not significantly (HR = 0.68; 95% CI 0.41-1.12; P = 0.129). Exploratory analysis demonstrated a trend toward longer median PFS (HR = 0.43; 95% CI 0.14-1.3; P = 0.124) and overall survival (OS; HR = 0.41; 95% CI 0.11-1.46; P = 0.155) in imetelstat-treated patients with short TL, but no improvement in median PFS and OS in patients with long TL (HR = 0.86; 95% CI 0.39-1.88; and HR = 0.51; 95% CI 0.2-1.28; P = 0.145). CONCLUSIONS: Maintenance imetelstat failed to improve PFS in advanced NSCLC patients responding to first-line therapy. There was a trend toward a improvement in median PFS and OS in patients with short TL. Short TL as a predictive biomarker will require further investigation for the clinical development of imetelstat.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Indóis/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Quimioterapia de Manutenção/métodos , Niacinamida/análogos & derivados , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Intervalo Livre de Doença , Inibidores Enzimáticos/uso terapêutico , Feminino , Humanos , Hibridização in Situ Fluorescente , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Niacinamida/uso terapêutico , Oligonucleotídeos , Modelos de Riscos Proporcionais , Telomerase/antagonistas & inibidores , Telômero/patologia
4.
Ann R Coll Surg Engl ; 96(4): 294-6, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24780022

RESUMO

INTRODUCTION: Limited resources and organisational problems often result in significant waiting times for patients presenting with an indication for cholecystectomy. This study investigated the potential false economy of such practice. METHODS: Retrospective analysis of all patients on a waiting list for cholecystectomy between July 2007 and October 2010 was performed. The hospital computer document management system and patients' notes were used to collect data. RESULTS: A total of 1,021 patients were included in the study; 701 were listed from clinic and 320 were listed following an emergency admission. The median time on a waiting list before surgery was 96 days (range: 5-381 days). Eighty-seven patients (8.5%) had an emergency admission with a gallstone related problem while on a waiting list. This resulted in 488 cumulative inpatient days. There was a significant correlation between increased time spent on the waiting list and increased chance of an emergency admission (p=0.01). Patients added to the waiting list from emergency admissions were more likely to be admitted with complications than those listed from clinic (15.3% vs 5.4%, p<0.01). There was no association between age (p=0.53) or sex (p=0.23) and likelihood of emergency admission while on a waiting list. CONCLUSIONS: Prompt elective surgery and same-admission emergency laparoscopic cholecystectomy can reduce waiting list patient morbidity and is likely to save resources in the long term.


Assuntos
Colecistectomia Laparoscópica/economia , Cálculos Biliares/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Colecistectomia Laparoscópica/estatística & dados numéricos , Procedimentos Cirúrgicos Eletivos/economia , Tratamento de Emergência/economia , Feminino , Cálculos Biliares/complicações , Cálculos Biliares/economia , Humanos , Tempo de Internação/economia , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tempo para o Tratamento , Listas de Espera , Adulto Jovem
5.
J Clin Endocrinol Metab ; 99(6): 2259-68, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24606087

RESUMO

CONTEXT: The GH-2000 and GH-2004 research groups developed a method for detecting GH misuse in athletes based on the measurement of serum IGF-I and procollagen type III amino-terminal propeptide (P-III-NP). There are reports that IGF-I is also misused by athletes, but currently there is no internationally recognized test designed to detect recombinant human IGF-I misuse. OBJECTIVE: The objective of the study was to examine the response of serum IGF-I, P-III-NP, and the GH-2000 score to recombinant human (rh) IGF-I/rhIGF binding protein-3 (IGFBP-3) administration in recreational athletes. DESIGN AND SETTING: This was a randomized, double-blind, placebo-controlled rhIGF-I/rhIGFBP-3 administration study at Southampton General Hospital (Southampton, United Kingdom). PARTICIPANTS: Fifty-six recreational athletes (26 women, 30 men) participated in the study. INTERVENTION: Participants were randomized to treatment with low-dose (30 mg/d) or high-dose (60 mg/d) rhIGF-I/rhIGFBP-3 complex or placebo for 28 days. Blood was collected throughout the drug administration and washout periods. Serum IGF-I and P-III-NP were measured using commercial immunoassays and GH-2000 scores were calculated. RESULTS: IGF-I, P-III-NP, and the GH-2000 score rose in response to both low- and high-dose rhIGF-I/rhIGFBP-3 administration. The relative maximum response of IGF-I (approximately 4-fold increase in women and men) was greater than that of P-III-NP (40%-50% increase in women, 35%-50% increase in men). The GH-2000 formulae, which incorporate IGF-I and P-III-NP results, detected up to 61% of women and 80% of men in the rhIGF-I/rhIGFBP-3 groups but, using IGF-I concentrations alone, the sensitivity increased to 94% in both women and men during the administration period. CONCLUSIONS: The rise in P-III-NP after rhIGF-I/rhIGFBP-3 administration is small compared with that after rhGH administration. Although rhIGF-I/rhIGFBP-3 administration can be detected using the GH-2000 score method, a test based on serum IGF-I alone provides better sensitivity.


Assuntos
Atletas , Biomarcadores Farmacológicos/sangue , Dopagem Esportivo , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/administração & dosagem , Fator de Crescimento Insulin-Like I/administração & dosagem , Fragmentos de Peptídeos/sangue , Pró-Colágeno/sangue , Proteínas Recombinantes/administração & dosagem , Detecção do Abuso de Substâncias/métodos , Adolescente , Adulto , Relação Dose-Resposta a Droga , Feminino , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Projetos de Pesquisa , Reino Unido , Adulto Jovem
6.
Drug Test Anal ; 5(11-12): 843-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24173773

RESUMO

Insulin-like growth factor-I (IGF-I) is reportedly misused by elite athletes, either alone or with growth hormone (GH). The GH-2000 and GH-2004 research groups previously developed a method for detecting GH misuse based on the GH-sensitive markers IGF-I and procollagen type III amino-terminal propeptide (P-III-NP). Both markers increase in response to rhIGF-I/rhIGF binding protein-3 (rhIGFBP-3) administration in recreational athletes. The aim of this pilot study was to assess the effect of rhIGF-I/rhIGFBP-3 administration on other serum markers of the GH-IGF axis and on other bone and collagen markers. Twenty-six female and 30 male recreational athletes were randomized to 28 days' treatment with placebo or rhIGF-I/rhIGFBP-3 complex, followed by 56 days' washout. GH-IGF axis markers (IGFBP-2, IGFBP-3, acid-labile subunit (ALS) and IGF-II) and bone and collagen markers (procollagen type I carboxy-terminal propeptide (PICP), type I collagen cross-linked carboxy-terminal telopeptide (ICTP) and osteocalcin) were measured using commercial immunoassays. In women in the high dose treatment group, mean IGF-II decreased by 53% (P=0.0028) on Day 21. Mean IGFBP-2 increased by 119% (P=0.0039) and mean ALS decreased by 40% (P=0.0022) on Day 21. There were no significant changes in IGFBP-3, osteocalcin, ICTP or PICP. In men in the high dose group, mean IGF-II decreased by 51% on Day 21 (P<0.0001). Mean IGFBP-2 increased by 125% on Day 21 (P=0.0003). There were no significant changes in IGFBP-3, ALS, osteocalcin, ICTP or PICP. Serum IGFBP-2 and IGF-II may be useful markers of rhIGF-I/rhIGFBP-3 administration in both women and men while ALS may also be a useful marker in women; these markers are now undergoing further evaluation.


Assuntos
Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/análise , Fator de Crescimento Insulin-Like I/análise , Adolescente , Adulto , Atletas , Biomarcadores/sangue , Osso e Ossos/química , Colágeno/análise , Feminino , Humanos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/administração & dosagem , Fator de Crescimento Insulin-Like I/administração & dosagem , Masculino , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/análise , Detecção do Abuso de Substâncias/métodos , Adulto Jovem
7.
Ann R Coll Surg Engl ; 95(8): 595-8, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24165344

RESUMO

INTRODUCTION: The gold standard for assessing neck lumps is a one-stop clinic with an on-site cytopathologist who can provide an immediate fine needle aspiration (FNA) report. However, this has considerable resource implications and is not available in all units. In our department, surgeons perform FNAs guided by palpation. The FNA is evaluated for specimen adequacy by an on-site cytotechnician. This study evaluated the impact of the cytotechnician on the adequacy of neck lump FNA. METHODS: FNA performed between June 2010 and February 2012 was examined. The FNA performed at a neck lump clinic with an assessment of adequacy by an on-site cytotechnician were considered the test group. All other neck lump FNAs from other sources without an assessment of adequacy by an on-site cytotechnician were considered the control group. RESULTS: Of the FNAs, 134 met the inclusion criteria for this study. Of these, 87 FNAs (65%) were analysed for adequacy by the on-site cytotechnician and the remaining 47 (35%) were not. The results demonstrated an FNA inadequacy with and without on-site cytotechnician assessment of 29.9% and 40.4% respectively. This is equivalent to an absolute risk reduction of an inadequate FNA of 10.5%, which equates to a number needed to treat of 9.5, ie the cytotechnician needs to assess 9.5 (ie the cytotechnician [...] specimen). CONCLUSIONS: In neck lump clinics where on-site cytopathology is not available, an on-site cytotechnician is a compromise measure that does reduce the number of inadequate FNAs.


Assuntos
Biópsia por Agulha Fina/normas , Neoplasias de Cabeça e Pescoço/diagnóstico , Assistência Ambulatorial , Humanos , Palpação , Sistemas Automatizados de Assistência Junto ao Leito/normas , Estudos Retrospectivos , Procedimentos Desnecessários
8.
Drug Test Anal ; 4(6): 455-9, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22511534

RESUMO

A method based on two serum biomarkers - insulin-like growth factor-I (IGF-I) and pro-collagen type III N-terminal propeptide (P-III-NP) - has been devised to detect growth hormone (GH) misuse. The aims of this study were to determine the stability of IGF-I and P-III-NP concentrations in serum stored at -20°C and to establish the effects of one freeze-thaw cycle. Blood was collected from 20 healthy volunteers. Serum aliquots were analyzed after storage for one day at 4°C and one day, one week, five weeks, and three months at -20°C. IGF-I and P-III-NP results were combined to calculate a GH-2000 discriminant function score for each volunteer. Inter-assay precision was determined by analysing one quality control sample at each time-point. A single freeze-thaw cycle, storage of serum at 4°C for one day and at -20°C for up to three months had no significant effect on IGF-I or P-III-NP concentration. Intra-sample variability for IGF-I was 6.8% (Immunotech assay) and 12.9% (DSL assay). Intra-sample variability for P-III-NP was 10.9% (Cisbio assay) and 13.7% (Orion assay). When IGF-I and P-III-NP results were combined, intra-sample variability of the GH-2000 score expressed as a standard deviation varied between 0.31 and 0.50 depending on the assay combination used. Variability in IGF-I and P--III-NP results of stored samples is largely determined by the characteristics of the assays. A single freeze-thaw cycle, storage of serum at 4°C for one day or at -20°C for up to 3 months does not result in a significant change in GH-2000 score.


Assuntos
Hormônio do Crescimento Humano/farmacologia , Fator de Crescimento Insulin-Like I/análise , Fragmentos de Peptídeos/sangue , Pró-Colágeno/sangue , Detecção do Abuso de Substâncias/métodos , Adulto , Atletas , Biomarcadores/sangue , Biomarcadores/química , Coleta de Amostras Sanguíneas/métodos , Dopagem Esportivo , Feminino , Congelamento , Humanos , Fator de Crescimento Insulin-Like I/química , Masculino , Fragmentos de Peptídeos/química , Pró-Colágeno/química , Estabilidade Proteica , Temperatura , Fatores de Tempo , Adulto Jovem
9.
Breast ; 21(3): 330-5, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22410111

RESUMO

BACKGROUND: The best management of large, diffuse or inflammatory breast cancers is uncertain and the place of radiotherapy and/or surgery is not clearly defined. METHODS: A cohort of 123 patients with non-metastatic locally advanced or inflammatory breast cancer 3 cm or more in diameter or T4, was treated between 1989 and 2006. All patients received primary chemotherapy followed by radiotherapy, 40 Gy in 15 fractions with 10 Gy boost. Patients with ER positive tumours received Tamoxifen. Assessment was carried out 8 weeks post-treatment and surgery was reserved for residual or recurrent disease. RESULTS: For each stage there were T2/3: 63, T4b: 31 and T4d: 29 patients. 80 had complete clinical response (65%) but 18 patients were never free of inoperable local disease. 25 patients had residual operable disease at assessment and 12 patients who initially had a complete response developed operable local recurrence (LR). 37 Patients (30%) had surgery at a mean of 15 months post diagnosis. At 5 years, overall survival (OS) of the two surgical groups was not significantly different from those 68 patients who had complete remission without surgery, p=0.218, HR 1.46 (0.80-2.55). Surgery as an independent variable to predict survival was not significant on a Cox proportional hazards model (p=0.97). LR in the surgical groups was 13.5% vs 17.5% in the non-surgical patients. The median OS was 64.5 months and disease-free survival (DFS) was 52.5 months. 5-Year OS was 54% and DFS survival 43%. CONCLUSION: In patients with a complete or partial response to chemo-radiotherapy for locally advanced or inflammatory breast cancer, reserving surgery for those with residual or recurrent local disease did not appear to compromise survival. This finding would support examination of this treatment strategy by a randomised controlled trial.


Assuntos
Neoplasias Inflamatórias Mamárias/tratamento farmacológico , Neoplasias Inflamatórias Mamárias/radioterapia , Saúde da Mulher , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Estudos de Coortes , Terapia Combinada , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Inflamatórias Mamárias/patologia , Mastectomia , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Radioterapia Adjuvante , Resultado do Tratamento , Reino Unido/epidemiologia , Adulto Jovem
10.
Growth Horm IGF Res ; 22(2): 53-8, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22305721

RESUMO

BACKGROUND: The GH-2000 project developed a method for detecting GH misuse based on the measurement of insulin-like growth factor-I (IGF-I) and the amino-terminal pro-peptide of type III collagen (P-III-NP). The objective of this study was to develop decision limits for the GH-2000 score to detect GH misuse in elite athletes using two currently available commercial assays for each analyte. SUBJECTS: 404 male (mean age 23.9 yrs, range 12-37 yrs) and 94 female elite athletes (mean age 24.5 yrs, range 18-34 yrs) participated. Blood samples were collected according to World Anti-Doping Agency (WADA) guidelines at various sporting events including 238 samples collected as part of the UK Anti-Doping Testing Programme. Laboratory analysis: IGF-I was measured by Siemens Immulite IGF-I assay and Immunotech A15729 IGF-I IRMA. P-III-NP was measured by RIA-gnost P-III-P and the UniQ™ PIIINP RIA. STATISTICAL ANALYSIS: The GH-2000 score decision limits were developed through the analysis of the elite athlete samples. RESULTS: For males and females separately, the distributions of GH-2000 scores were consistent with Normal distributions. Using a specificity of 99.99% new decision limits were determined which included an allowance for uncertainty associated with calculations based on a finite sample size. One outlier was identified with results incompatible with normal physiology and tested positive with the current isoform GH test. CONCLUSIONS: We have developed decision limits using currently available commercial assays to measure IGF-I and P-III-NP in elite athletes. This should allow the introduction of a test for GH misuse based on the measurement of these GH sensitive biomarkers.


Assuntos
Atletas , Colágeno/química , Fator de Crescimento Insulin-Like I/metabolismo , Fragmentos de Peptídeos/biossíntese , Pró-Colágeno/biossíntese , Detecção do Abuso de Substâncias/normas , Adolescente , Adulto , Biomarcadores/metabolismo , Criança , Dopagem Esportivo/métodos , Feminino , Humanos , Masculino , Peptídeos/química , Valores de Referência , Sensibilidade e Especificidade , Fatores Sexuais , Esportes/fisiologia , Detecção do Abuso de Substâncias/métodos
11.
Eur J Endocrinol ; 163(1): 45-54, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20421332

RESUMO

CONTEXT: The GH-2000 team proposed a method based on IGF1 and type III pro-collagen (P-III-P) to detect exogenously administered GH. As previous studies involved predominantly white European athletes, it is important to assess whether the response of these markers to recombinant human GH (rhGH) differs with ethnicity. OBJECTIVE: To examine the response of serum IGF1 and P-III-P and GH-2000 score to rhGH in non-Caucasian amateur athletes. DESIGN: Double-blind placebo-controlled rhGH administration study. SETTING: Wellcome Trust Clinical Research Facility, Southampton General Hospital. SUBJECTS: The study included 31 male and 14 female amateur athletes of different ethnicities. Intervention The subjects were assigned to treatment with placebo or 0.1 IU/kg per day (low dose) or 0.2 IU/kg per day (high dose) rhGH for 28 days. Blood was collected weekly during treatment and on days 35, 42 and 84 during the washout period. Serum IGF1 and P-III-P were measured, and GH-2000 score was calculated. RESULTS: IGF1, P-III-P and GH-2000 score rose in response to both low- and high-dose GH in both men and women. When compared with the Caucasian volunteers of the previous GH-2000 study, mean baseline and placebo-treated P-III-P and GH-2000 score were lower in GH-2004 men and women. Post-GH, however, peak IGF1 or P-III-P did not differ between studies but the peak GH-2000 score was lower in GH-2004 men. There was no difference between studies in the maximal change in IGF1, P-III-P and GH-2000 score in response to GH in either gender. CONCLUSIONS: These data do not support a significant ethnic effect on the peak or maximal response to rhGH.


Assuntos
Atletas , Colágeno Tipo III/sangue , Hormônio do Crescimento/farmacologia , Fator de Crescimento Insulin-Like I/metabolismo , Adolescente , Adulto , Dopagem Esportivo/etnologia , Feminino , Hormônio do Crescimento/administração & dosagem , Humanos , Masculino , Efeito Placebo , Grupos Raciais , Adulto Jovem
12.
J Clin Endocrinol Metab ; 95(6): 2969-76, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20410221

RESUMO

CONTEXT: A method based on two GH-dependent markers, IGF-I and pro-collagen type III N-terminal peptide (P-III-P), has been devised to detect exogenously administered GH. Because previous studies on the detection of GH abuse involved predominantly adult athletes, the method must be validated in adolescent athletes. OBJECTIVE: The aim of the study was to examine serum IGF-I and P-III-P concentrations in elite adolescent athletes and to determine whether the method developed in adults is appropriate to detect GH abuse in this population. DESIGN AND SETTING: We conducted a cross-sectional observational study at national sporting organization training events. SUBJECTS: A total of 157 (85 males, 72 females) elite athletes between 12 and 20 yr of age participated in the study. INTERVENTION: Serum IGF-I and P-III-P were each measured by two commercially available immunoassays. GH-2000 discriminant function scores were calculated. RESULTS: Both IGF-I and P-III-P rose to a peak during adolescence, which was earlier in girls than in boys. All GH-2000 scores lay below the proposed cutoff limit of 3.7 (although some scores were close to this value), indicating that none of these athletes would be accused of GH doping if the GH-2000 discriminant formulae were used. The results between the two immunoassays for IGF-I and P-III-P were closely aligned. CONCLUSIONS: The GH-2000 score rises in early adolescence, reaches a peak in athletes aged 13-16 yr, and then falls. We have found no evidence that the proposed GH-2000 score developed in adults would lead to an unacceptable rate of false-positive results in adolescent athletes, but caution may be required around the time of peak growth velocity.


Assuntos
Colágeno Tipo III/sangue , Dopagem Esportivo/métodos , Hormônio do Crescimento Humano/farmacologia , Fator de Crescimento Insulin-Like I/metabolismo , Pró-Colágeno/sangue , Esportes/fisiologia , Detecção do Abuso de Substâncias/métodos , Adolescente , Envelhecimento/metabolismo , Estatura/fisiologia , Índice de Massa Corporal , Peso Corporal/fisiologia , Criança , Estudos Transversais , Epitopos , Reações Falso-Positivas , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Caracteres Sexuais , Adulto Jovem
13.
Clin Endocrinol (Oxf) ; 72(4): 520-6, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19650783

RESUMO

BACKGROUND: Growth Hormone is abused by athletes for its lipolytic and anabolic properties. Its use is prohibited by the World Anti-Doping Agency. The GH-2000 project developed a methodology to detect its abuse using the concentrations of two GH-dependent biomarkers, IGF-I and type 3 procollagen (P-III-P). The sensitivity of this method may be improved by considering intra-individual variability. AIM: The aim of this study was to examine the intra-individual variability of IGF-I, P-III-P and the GH-2000 score. SUBJECTS AND METHODS: IGF-I, P-III-P and GH-2000 score were evaluated in four longitudinal studies involving 303 elite and 78 amateur athletes. Samples were collected over a period of up to 12 months from a total of 238 men and 143 women aged between 17 and 53 years (mean 24.2). RESULTS: The four studies showed good agreement with no apparent difference in within-individual variation between amateur and elite athletes. The intra-individual variability for IGF-I ranged between 14-16% while the variability for P-III-P was 7-18%. No athlete tested positive for growth hormone during any of the studies. The overall mean intra-individual variability of the GH-2000 score was less than 0.6 units in all studies. CONCLUSIONS: The high stability of marker levels suggests that concentrations are largely genetically determined. Adopting a test based on the concept of an athlete's 'passport' or 'profiling' would take advantage of this and most likely increase the sensitivity of the test. These data also provide strong evidence that a positive test result for GH abuse would not occur as a result of chance variability.


Assuntos
Biomarcadores/análise , Hormônio do Crescimento Humano/análise , Fator de Crescimento Insulin-Like I/análise , Fragmentos de Peptídeos/sangue , Pró-Colágeno/sangue , Detecção do Abuso de Substâncias/métodos , Adolescente , Adulto , Análise de Variância , Dopagem Esportivo/métodos , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
14.
Growth Horm IGF Res ; 19(4): 361-5, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19515593

RESUMO

The detection of growth hormone (GH) abuse by athletes raises statistical problems as well as biochemical ones. We outline the statistical approaches to the various issues which have arisen during the work of the GH-2000 and GH-2004 teams; in particular, it considers the need to develop a test which detects GH abuse in any elite athlete 'beyond reasonable doubt'. The test needs to be robust enough to withstand legal challenge, while minimising the risk of false accusation. The paper identifies various issues which arise in the development of such a test, and describes how these were resolved. Since GH is a naturally occurring hormone whose concentration varies substantially, its abuse cannot be detected by direct measurement. The methodology considered here made use of markers whose levels are more stable but are influenced by GH. The statistical methods employed aimed to make the best use of these markers, taking account of all factors contributing to errors in measurement. There were two key steps in the statistical investigation undertaken to develop the GH detection algorithm. The first was the requirement to identify GH-dependent biomarkers which would identify GH doping reliably and robustly for a significant length of time. The second was to calibrate the GH detection method in the elite athlete population, so that the method would be applicable to all athletes, regardless of age, sex and ethnicity, and regardless of whether they had recently sustained an injury. In practice, further work was needed to ensure that the methodology met the WADA testing protocol rules, but also that the proposed method can be used by any WADA accredited lab without placing any athlete at an unfair disadvantage and ensuring a high level of confidence in any result produced.


Assuntos
Atletas , Biomarcadores/metabolismo , Dopagem Esportivo , Hormônio do Crescimento Humano/uso terapêutico , Detecção do Abuso de Substâncias/métodos , Adolescente , Adulto , Algoritmos , Criança , Interpretação Estatística de Dados , Feminino , Hormônio do Crescimento Humano/análise , Humanos , Masculino , Modelos Estatísticos , Reprodutibilidade dos Testes , Detecção do Abuso de Substâncias/instrumentação
15.
Growth Horm IGF Res ; 19(4): 346-51, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19467613

RESUMO

Growth hormone is abused by athletes for its anabolic and lipolytic properties. The detection of GH abuse is challenging because it is an endogenous hormone whose concentration varies widely in any one day. The GH-2000 project proposed a test based on the measurement of IGF-I and type III pro-collagen (P-III-P). When the results of the GH-2000 project were presented to an expert workshop, the method was supported but it was felt that several issues needed to be resolved before the method could be adopted. The first was a potential effect of ethnicity as most subjects in the GH-2000 were white Europeans and the second was a possible effect of injury as P-III-P is a marker of soft tissue turnover. The GH-2004 project was conceived to address these concerns. The GH-2004 project has shown that while there are minor differences in IGF-I and P-III-P between ethnicities, these are small and do not affect the performance of the test. Injury leads to a small rise in P-III-P but again this is not of sufficient magnitude to affect the performance of the test. The GH-2004 project has provided further support for the marker approach as a means of detecting GH abuse in athletes. As WADA have not developed their own immunoassays, however, further work is needed to validate newer commercial assays measuring IGF-I and P-III-P to establish reliable conversion factors to the original GH-2000 units to allow the published formulae to be used.


Assuntos
Atletas , Dopagem Esportivo , Hormônio do Crescimento Humano/uso terapêutico , Fator de Crescimento Insulin-Like I/uso terapêutico , Fragmentos de Peptídeos/uso terapêutico , Pró-Colágeno/uso terapêutico , Proteínas Recombinantes/uso terapêutico , Detecção do Abuso de Substâncias/métodos , Biomarcadores , Europa (Continente) , Feminino , Hormônio do Crescimento Humano/análise , Humanos , Cooperação Internacional , Masculino , Isoformas de Proteínas , Proteínas Recombinantes/análise , Manejo de Espécimes
16.
Clin Endocrinol (Oxf) ; 70(1): 161-8, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18616716

RESUMO

CONTEXT: A method based on the two GH dependent markers, IGF-I and procollagen III peptide (P-III-P) has been proposed to detect exogenously administered GH. As previous studies involved predominantly white European elite athletes, it is necessary to validate the method in other ethnic groups. OBJECTIVE: To examine serum IGF-I and P-III-P in elite athletes of different ethnicities within 2 h of competing at national or international events. DESIGN: Cross-sectional observational study. SETTING: National and International sporting events. SUBJECTS: 1085 elite athletes of different ethnicities. INTERVENTION: Serum IGF-I and P-III-P were measured and GH-2000 discriminant function score was calculated. Effect of ethnicity was assessed. RESULTS: In men, IGF-I was 21.7 +/- 2.6% lower in Afro-Caribbeans than white Europeans (P < 0.0001) but there were no differences between other ethnic groups. In women, IGF-I was 14.2 +/- 5.1% lower in Afro-Caribbeans (P = 0.005) and 15.6 +/- 7.0% higher in Orientals (P = 0.02) compared with white Europeans. P-III-P was 15.2 +/- 3.5%, 26.6 +/- 6.6% and 19.3 +/- 5.8% lower in Afro-Caribbean (P < 0.0001), Indo-Asian (P < 0.0001) and Oriental men (P = 0.001), respectively, compared with white European men. In women, P-III-P was 15.7 +/- 4.7% lower in Afro-Caribbeans compared to white Europeans (P =0.0009) but there were no differences between other ethnicities. Despite these differences, most observations were below the upper 99% prediction limits derived from white European athletes. All GH-2000 scores lay below the cut-off limit proposed for doping. CONCLUSIONS: The GH-2000 detection method based on IGF-I and P-III-P would be valid in all ethnic groups.


Assuntos
Etnicidade , Hormônio do Crescimento Humano/análise , Fator de Crescimento Insulin-Like I , Fragmentos de Peptídeos , Pró-Colágeno , Esportes , Detecção do Abuso de Substâncias/métodos , Adolescente , Adulto , Envelhecimento , Povo Asiático/genética , População Negra/genética , Dopagem Esportivo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/sangue , Pró-Colágeno/sangue , População Branca/genética
17.
Growth Horm IGF Res ; 19(1): 43-50, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18617430

RESUMO

OBJECTIVE: IGF-I and type III procollagen (P-III-P) have been proposed as markers to detect GH abuse. This study aims to determine whether the pre-analytical storage temperature or delayed centrifugation affect the measured IGF-I and P-III-P concentrations. DESIGN: Observational study. SETTING: Wellcome Trust Clinical Research Facility, Southampton. SUBJECTS: Nineteen healthy volunteers. INTERVENTION: Blood was collected into bottles containing a clotting agent, lithium heparin or EDTA. One sample from each group was centrifuged and stored at -80 degrees C (control sample). The remaining samples from each group were stored as either serum or whole blood at 4 degrees C or room temperature for up to five days prior to storage at -80 degrees C. OUTCOME MEASURES: IGF-I and P-III-P. RESULTS: The storage temperature or timing of centrifugation did not appear to affect IGF-I concentration. In contrast, the measured P-III-P concentration rose by 6.5-7% per day in clotted and lithium heparin samples when stored as whole blood (p<0.006) or serum (6.2-6.5% per day) at room temperature (p<0.001). P-III-P did not change when the samples were stored at 4 degrees C. Although collection into EDTA inhibited the rise in P-III-P, the baseline measured values were significantly higher than in other media and spiking experiments demonstrated that EDTA exerted a significant matrix effect on the assay. CONCLUSION: While the optimum collection method is immediate centrifugation and storage at -80 degrees C, it would seem acceptable to store serum or clotted blood samples at 4 degrees C, but not ambient temperature, for up to five days. It is incumbent on the anti-doping authorities to provide facilities to allow this.


Assuntos
Preservação de Sangue/métodos , Coleta de Amostras Sanguíneas/métodos , Colágeno Tipo III/química , Fator de Crescimento Insulin-Like I/química , Colágeno Tipo III/sangue , Ácido Edético/química , Heparina/química , Humanos , Temperatura
18.
Connect Tissue Res ; 49(5): 321-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18991085

RESUMO

This work was designed to determine the course of development of elastic fibers in myocardial scars in rats and their relationship to other components of such structures. Light and electron microscopic observations were made on tissues from 24 rats, killed at sequent stages from 4 to 24 days postinjury. By both techniques, elastic fibers, shown to be forming by 4 days, had increased in size and number with maturation of the scar. At later stages they became interdigitated with the stumps of viable myocytes. We also saw that these fibers often had formed close contacts with the cell surfaces of myofibroblasts and nonvascular smooth muscle cells; a process found in some other situations but not previously in myocardial scars. This information is relevant, in particular, to the dynamics of myocardial scars and thus to the maintenance of function in the injured heart, but also to elastic fiber behavior in general. The integral role of elastic fibers in cell-matrix interactions as well as their biomechanical function is emphasized.


Assuntos
Cicatriz/patologia , Tecido Elástico/crescimento & desenvolvimento , Tecido Elástico/ultraestrutura , Traumatismos Cardíacos/patologia , Miocárdio/ultraestrutura , Animais , Fibroblastos/ultraestrutura , Masculino , Microscopia Eletrônica de Transmissão , Células Musculares/ultraestrutura , Ratos , Ratos Sprague-Dawley
19.
J Clin Endocrinol Metab ; 93(7): 2760-3, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18413420

RESUMO

CONTEXT: A method to detect exogenously administered growth hormone (GH) based on the measurement of two GH-dependent markers, IGF-I and type 3 procollagen (P-III-P) has been proposed. Skeletal or soft tissue injury may alter these markers. Elevations in either of these proteins after injury might lead to a false accusation of doping with GH. OBJECTIVE: The objective of the study was to assess the effect of musculoskeletal or soft tissue injury on IGF-I and P-III-P concentrations in amateur and elite athletes and assess the effect of injury on the proposed GH detection method. DESIGN: This was a longitudinal observational study after sporting injury. SETTING: The study was conducted at Southampton General Hospital and British Olympic Medical Centre. SUBJECTS: Subjects included elite and amateur athletes after an injury. INTERVENTION: Interventions included measurement of IGF-I and P-III-P and application of the GH-2000 discriminant function score up to 84 d after an injury as well as classification of injury by type and severity. OUTCOME MEASURES: IGF-I and P-III-P concentration and ability to detect GH abuse in athletes without the risk of false accusation because of an injury were measured. RESULTS: There was no change in IGF-I concentration after an injury. By contrast, P-III-P concentrations rose by 41.1 +/- 16.6%, reaching a peak around 14 d after an injury. The rise in P-III-P varied according to injury type and severity. This rise had a trivial effect on the GH-2000 discriminant function score, and no subject reached the threshold needed for a doping offense. CONCLUSIONS: Although there was a rise in P-III-P after injury, this was insufficient to invalidate the GH-2000 detection method based on IGF-I and P-III-P concentrations.


Assuntos
Traumatismos em Atletas/sangue , Colágeno Tipo III/sangue , Dopagem Esportivo , Hormônio do Crescimento Humano/metabolismo , Fator de Crescimento Insulin-Like I/análise , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Adolescente , Adulto , Idoso , Feminino , Consolidação da Fratura , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade
20.
Growth Horm IGF Res ; 17(5): 416-23, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17584513

RESUMO

CONTEXT: The detection of exogenously administered growth hormone (GH) poses a formidable challenge but a detection method based on the measurement of two GH-dependent markers, IGF-I and type 3 pro-collagen (P-III-P) has been proposed. The measurement of multiple markers in conjunction with discriminant functions can improve the sensitivity and specificity of detection compared with single marker analysis. OBJECTIVE: To provide further validation of the GH-dependent marker approach. DESIGN: Analysis of discriminant function scores for GH detection on independent datasets. SETTING: Two independent (GH-2000 and Kreischa) double blind, placebo controlled, hGH administration studies. SUBJECTS: Healthy active male volunteers. INTERVENTION: GH-2000 proposed a discriminant function involving IGF-I and P-III- P while the Kreischa function involved IGF-I, P-III-P and IGFBP-3. After adjustment for assay differences the formulae were applied to the other dataset. OUTCOME MEASURES: Ability to detect GH use in independent datasets using a predefined specificity of approximately 1 in 10000. RESULTS: The GH-2000 formula was able to detect 90% of those receiving GH in the Kreischa study at one or more time points during the study period. This sensitivity was similar to that obtained on the original GH-2000 dataset. The Kreischa formula correctly identified 41% of individuals receiving GH in the GH-2000 study. CONCLUSIONS: The study provides further validation that the test proposed by GH-2000 based on IGF-I and P-III-P concentrations can be used to detect subjects receiving exogenous GH.


Assuntos
Dopagem Esportivo , Hormônio do Crescimento Humano/sangue , Hormônio do Crescimento Humano/farmacologia , Adulto , Método Duplo-Cego , Humanos , Masculino , Placebos , Proteínas Recombinantes/sangue , Proteínas Recombinantes/farmacologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Transtornos Relacionados ao Uso de Substâncias/diagnóstico
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