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1.
J Clin Endocrinol Metab ; 109(2): e735-e744, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-37672642

RESUMO

BACKGROUND: Arteries from boys with hypospadias demonstrate hypercontractility and impaired vasorelaxation. The role of sex hormones in these responses in unclear. AIMS: We compared effects of sex steroids on vascular reactivity in healthy boys and boys with hypospadias. METHODS: Excess foreskin tissue was obtained from 11 boys undergoing hypospadias repair (cases) and 12 undergoing routine circumcision (controls) (median age [range], 1.5 [1.2-2.7] years) and small resistance arteries were isolated. Vessels were mounted on wire myographs and vascular reactivity was assessed in the absence/presence of 17ß-estradiol, dihydrotestosterone (DHT), and testosterone. RESULTS: In controls, testosterone and 17ß-estradiol increased contraction (percent of maximum contraction [Emax]: 83.74 basal vs 125.4 after testosterone, P < .0002; and 83.74 vs 110.2 after estradiol, P = .02). 17ß-estradiol reduced vasorelaxation in arteries from controls (Emax: 10.6 vs 15.6 to acetylcholine, P < .0001; and Emax: 14.6 vs 20.5 to sodium nitroprusside, P < .0001). In hypospadias, testosterone (Emax: 137.9 vs 107.2, P = .01) and 17ß-estradiol (Emax: 156.9 vs 23.6, P < .0001) reduced contraction. Androgens, but not 17ß-estradiol, increased endothelium-dependent and endothelium-independent vasorelaxation in cases (Emax: 77.3 vs 51.7 with testosterone, P = .02; and vs 48.2 with DHT to acetylcholine, P = .0001; Emax: 43.0 vs 39.5 with testosterone, P = .02; and 39.6 vs 37.5 with DHT to sodium nitroprusside, P = .04). CONCLUSION: In healthy boys, testosterone and 17ß-estradiol promote a vasoconstrictor phenotype, whereas in boys with hypospadias, these sex hormones reduce vasoconstriction, with androgens promoting vasorelaxation. Differences in baseline artery function may therefore be sex hormone-independent and the impact of early-life variations in androgen exposure on vascular function needs further study.


Assuntos
Acetilcolina , Hipospadia , Masculino , Humanos , Lactente , Nitroprussiato/farmacologia , Hipospadia/cirurgia , Testosterona/farmacologia , Estradiol/farmacologia , Androgênios/farmacologia , Di-Hidrotestosterona/farmacologia
2.
J Pediatr Hematol Oncol ; 43(6): e861-e863, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32925398

RESUMO

Hemorrhagic cystitis is a life-threatening condition in which the transitional epithelium and blood vessels of the bladder necrose leading to severe hematuria, abdominal pain, and voiding lower urinary tract symptoms. Etiology includes chemotherapy (cyclophosphamide, ifosfamide, busulfan), radiotherapy, or infectious agents. We present a pediatric case of a 15-year-old boy with medulloblastoma who developed hemorrhagic cystitis following cisplatin chemotherapy. All other causes were ruled out and it is therefore likely that the agent, in this case, was cisplatin, which has never had hemorrhagic cystitis reported as a side effect. We also suggest a mechanism for urothelial injury centered around OCT-2 receptors.


Assuntos
Antineoplásicos/efeitos adversos , Neoplasias Cerebelares/tratamento farmacológico , Cisplatino/efeitos adversos , Cistite/induzido quimicamente , Hemorragia/induzido quimicamente , Meduloblastoma/tratamento farmacológico , Adolescente , Antineoplásicos/uso terapêutico , Cisplatino/uso terapêutico , Humanos , Masculino
3.
J Pediatr Urol ; 16(3): 299-303, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32234419

RESUMO

INTRODUCTION: The association between posterior urethral valves (PUVs) and hypospadias has previously been reported in case reports. After the identification of this twin pathology in a number of patients, a national retrospective review of all patients with this dual diagnosis was performed. PATIENTS AND METHODS: All patients were identified in each centre from surgical databases of prospectively collated information on all surgical procedures. The medical notes were reviewed to ascertain demographics, the type of hypospadias, the mode of presentation of the valves and the outcome. RESULTS: Twenty-eight patients who had the dual diagnosis of hypospadias and PUV between 2002 and 2017 in the four tertiary paediatric centres where specialist paediatric urology is undertaken in our country were identified. Most patients (n = 24) had the valves diagnosed after hypospadias surgery. The median age at the time of hypospadias surgery was 1.4 years (range 1-4 years). There were 12 proximal and 16 mid or distal hypospadias. The commonest presentation was with problems voiding after surgery in 14 cases with a further seven boys who had urinary tract infections. Four patients had a urethro-cutaneous fistula after repair that initiated further assessment. Two boys had distal dehiscence of their repair. There was one boy presented with new onset daytime incontinence. The median time of follow-up after valve incision surgery was 4.9 years (range 0.1-12.3 years). Twenty-two patients (three pre toilet training) had no ongoing urinary symptoms. Twenty-one boys have normal renal function with one patient in stage 3b chronic kidney disease. The incidence of this dual diagnosis in Scotland is estimated at one in 100 cases of hypospadias in the paediatric population. CONCLUSION: The incidence of PUV in boys with hypospadias is estimated at 1% patients.


Assuntos
Hipospadia , Uretra , Obstrução Uretral , Criança , Pré-Escolar , Humanos , Hipospadia/epidemiologia , Hipospadia/cirurgia , Lactente , Masculino , Estudos Retrospectivos , Escócia/epidemiologia , Resultado do Tratamento , Uretra/cirurgia , Obstrução Uretral/cirurgia
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