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1.
Endocr Oncol ; 2(1): R78-R89, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37435459

RESUMO

Hyponatraemia is a common electrolyte abnormality seen in a wide range of oncological and haematological malignancies and confers poor performance status, prolonged hospital admission and reduced overall survival, in patients with cancer. Syndrome of inappropriate antidiuresis (SIAD) is the commonest cause of hyponatraemia in malignancy and is characterised by clinical euvolaemia, low plasma osmolality and concentrated urine, with normal renal, adrenal and thyroid function. Causes of SIAD include ectopic production of vasopressin (AVP) from an underlying tumour, cancer treatments, nausea and pain. Cortisol deficiency is an important differential in the assessment of hyponatraemia, as it has an identical biochemical pattern to SIAD and is easily treatable. This is particularly relevant with the increasing use of immune checkpoint inhibitors, which can cause hypophysitis and adrenalitis, leading to cortisol deficiency. Guidelines on the management of acute, symptomatic hyponatraemia recommend 100 mL bolus of 3% saline with careful monitoring of the serum sodium to prevent overcorrection. In cases of chronic hyponatraemia, fluid restriction is recommended as first-line treatment; however, this is frequently not feasible in patients with cancer and has been shown to have limited efficacy. Vasopressin-2 receptor antagonists (vaptans) may be preferable, as they effectively increase sodium levels in SIAD and do not require fluid restriction. Active management of hyponatraemia is increasingly recognised as an important component of oncological management; correction of hyponatraemia is associated with shorter hospital stay and prolonged survival. The awareness of the impact of hyponatraemia and the positive benefits of active restoration of normonatraemia remain challenging in oncology.

2.
J Crohns Colitis ; 16(2): 216-223, 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-34379117

RESUMO

BACKGROUND: Canadian-born children of South Asian [SA] ethnicity develop inflammatory bowel disease [IBD] at similar rates to those among Caucasian children. We evaluated the variation in phenotypic spectrum of IBD in SA and Caucasian children in a national paediatric inception cohort of new-onset IBD. METHODS: Patients aged <17 years, enrolled in a Canadian nationwide inception cohort study, were included. Baseline demographic and IBD phenotypic features were compared between SA and Caucasian children. Longitudinal outcomes through 18 months of follow-up were compared matched by propensity scores. RESULTS: Of 1156 children enrolled over 2014 to 2019, 623 were Caucasian [98% and 88% parents Canadian born] and 114 SA [79% Canadian born, 87% parents SA born]. Fewer SAs have a first-degree relative with IBD, 6% vs 19% in Caucasians, p = 0.002. SAs present at a younger age, median age 11.4 years (interquartile range [IQR] 9.2-14.3) vs 13 years [IQR 10.9-15 years], p = 0.03 and more commonly with a UC/IBD-U [ulcerative colitis/IBD-unclassified] subtype [ratio of UC/IBD-U to CD 1.2:1 vs 1:1.8 for Caucasians, p <0.001]. Additionally, a greater proportion of SA CD patients present with colonic-only disease [colonic-only CD/UC/IBD-U in SAs 67% vs 57% for Caucasians, p = 0.001], and among those with CD, colonic CD in SAs 31% vs 23% in Caucasians, p = 0.20]. Perianal fistulising disease was also numerically more common in SAs (14 [27%] vs 64 [18%], p = 0.06]. Adjusting for differences in phenotypic presentation, anti-tumour necrosis factor [TNF] exposure, and time to initiation was similar, and two-thirds of children, whether anti-TNF exposed or naïve, were in corticosteroid-free clinical remission at 18 months irrespective of ethnicity. CONCLUSIONS: The phenotypic spectrum of new-onset IBD in SA children differs from that of Caucasian children, but treatment and clinical course are similar within phenotypic subgroups.


Assuntos
Colite Ulcerativa , Doença de Crohn , Doenças Inflamatórias Intestinais , Adolescente , Canadá/epidemiologia , Criança , Estudos de Coortes , Colite Ulcerativa/terapia , Doença de Crohn/terapia , Etnicidade , Humanos , Estudos Prospectivos , Inibidores do Fator de Necrose Tumoral
3.
Eur J Endocrinol ; 186(1): 25-36, 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34709200

RESUMO

OBJECTIVE: Adrenocortical carcinoma (ACC) has an aggressive but variable clinical course. Prognostic stratification based on the European Network for the Study of Adrenal Tumours stage and Ki67 index is limited. We aimed to demonstrate the prognostic role of a points-based score (S-GRAS) in a large cohort of patients with ACC. DESIGN: This is a multicentre, retrospective study on ACC patients who underwent adrenalectomy. METHODS: The S-GRAS score was calculated as a sum of the following points: tumour stage (1-2 = 0; 3 = 1; 4 = 2), grade (Ki67 index 0-9% = 0; 10-19% = 1; ≥20% = 2 points), resection status (R0 = 0; RX = 1; R1 = 2; R2 = 3), age (<50 years = 0; ≥50 years = 1), symptoms (no = 0; yes = 1), and categorised, generating four groups (0-1, 2-3, 4-5, and 6-9). Endpoints were progression-free survival (PFS) and disease-specific survival (DSS). The discriminative performance of S-GRAS and its components was tested by Harrell's Concordance index (C-index) and Royston-Sauerbrei's R2D statistic. RESULTS: We included 942 ACC patients. The S-GRAS score showed superior prognostic performance for both PFS and DSS, with best discrimination obtained using the individual scores (0-9) (C-index = 0.73, R2D = 0.30, and C-index = 0.79, R2D = 0.45, respectively, all P < 0.01vs each component). The superiority of S-GRAS score remained when comparing patients treated or not with adjuvant mitotane (n = 481 vs 314). In particular, the risk of recurrence was significantly reduced as a result of adjuvant mitotane only in patients with S-GRAS 4-5. CONCLUSION: The prognostic performance of S-GRAS is superior to tumour stage and Ki67 in operated ACC patients, independently from adjuvant mitotane. S-GRAS score provides a new important guide for personalised management of ACC (i.e. radiological surveillance and adjuvant treatment).


Assuntos
Neoplasias do Córtex Suprarrenal/diagnóstico , Carcinoma Adrenocortical/diagnóstico , Técnicas de Diagnóstico Endócrino , Neoplasias do Córtex Suprarrenal/mortalidade , Neoplasias do Córtex Suprarrenal/patologia , Neoplasias do Córtex Suprarrenal/cirurgia , Adrenalectomia , Carcinoma Adrenocortical/mortalidade , Carcinoma Adrenocortical/patologia , Carcinoma Adrenocortical/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Prognóstico , Projetos de Pesquisa , Estudos Retrospectivos , Análise de Sobrevida
4.
J Crohns Colitis ; 14(4): 445-454, 2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-31136648

RESUMO

BACKGROUND AND AIMS: Incidence of paediatric inflammatory bowel disease [IBD] in Canada is among the highest worldwide, and age of onset may be decreasing. In a multicentre nationwide inception cohort study, we examined variation in phenotype of IBD throughout the paediatric age spectrum. METHODS: Children aged ≥2 years [y] and <17y [A1 age at diagnosis], with new onset IBD, were systematically evaluated at sites of the Canadian Children IBD Network. Prospectively recorded phenotypic data were compared between age groups. RESULTS: Among 1092 children (70% Caucasian; 64% Crohn's disease [CD], 36% ulcerative colitis/inflammatory bowel disease unclassified [UC/IBD-U]; median age 13 y, interquartile range [IQR] 11-15 y), 210 [19%] were diagnosed before the age of age 10 y [Paris A1a] and 43 [4%] before age 6 y (very-early-onset [VEO-IBD]). CD was less common in younger children [42%, 56%, 66%, respectively, of VEO-IBD, A1a; A1b]. Colon-only IBD [UC/IBDU or CD-colon] was present in 81% of VEO-IBD and 65% of A1a; ileal disease increased progressively, reaching plateau at age 10 y. CD location was ileocolonic [L3] in 53% overall. Ileitis [L1] increased with age [6% of VEO-IBD; 13% of A1a; 21% of A1b], as did stricturing/penetrating CD [4% of A1a; 11% of A1b]. At all ages UC was extensive [E3/E4] in >85%, and disease activity moderate to severe according to Physician's Global Assessment [PGA] and weighted Paediatric Crohn's Disease Activity Index/Paediatric Ulcerative Colitis Activity Index [wPCDAI/PUCAI] in >70%. Heights were modestly reduced in CD [mean height z score -0.30 ± 1.23], but normal in UC/IBD-U. CONCLUSIONS: Paris classification of age at diagnosis is supported by age-related increases in ileal disease until age 10 years. Other phenotypic features, including severity, are similar across all ages. Linear growth is less impaired in CD than in historical cohorts, reflecting earlier diagnosis.


Assuntos
Colite Ulcerativa , Doença de Crohn , Idade de Início , Variação Biológica da População , Canadá/epidemiologia , Criança , Estudos de Coortes , Colite Ulcerativa/diagnóstico , Colite Ulcerativa/epidemiologia , Colite Ulcerativa/fisiopatologia , Doença de Crohn/diagnóstico , Doença de Crohn/epidemiologia , Doença de Crohn/fisiopatologia , Progressão da Doença , Feminino , Humanos , Incidência , Masculino , Estudos Prospectivos , Índice de Gravidade de Doença
5.
Phys Rev Lett ; 123(21): 215001, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31809125

RESUMO

Shocks are abundant both in astrophysical and laboratory systems. While the electric fields generated at shock fronts have recently attracted great attention, the associated self-generated magnetic field is rarely studied, despite its ability to significantly affect the shock profile in the nonideal geometry where density and temperature gradients are not parallel. We report here the observation of a magnetic field at the front of a Mach ∼6 shock propagating in a low-density helium gas system. Proton radiography from different projection angles not only confirms the magnetic field's existence, but also provides a quantitative measurement of the field strength in the range ∼5 to 7 T. X-ray spectrometry allowed inference of the density and temperature at the shock front, constraining the plasma conditions under which the magnetic and electric fields are generated. Simulations with the particle-in-cell code lsp attribute the self-generation of the magnetic field to the Biermann battery effect (∇n_{e}×∇T_{e}).

6.
Hum Reprod ; 33(9): 1727-1734, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30020477

RESUMO

STUDY QUESTION: What information does androgen profiling using liquid chromatography tandem mass spectrometry (LC-MS/MS) provide in reproductive-age women with Type 1 diabetes (T1D)? SUMMARY ANSWER: In T1D women, androstenedione proved most useful of the measured androgens in differentiating subgroups based on clinical phenotypes of hyperandrogenism (HA) and polycystic ovary syndrome (PCOS). WHAT IS KNOWN ALREADY: The prevalence of HA and PCOS are increased in women with T1D. These observations are based on measurement of serum androgens using immunoassays, to-date no studies using LC-MS/MS have been reported in reproductive-age women with T1D. STUDY DESIGN, SIZE, DURATION: This was a cross-sectional study with recruitment of three groups of reproductive-age women: women with T1D (n = 87), non-diabetic women with (N = 97) and without PCOS (N = 101). PARTICIPANTS/MATERIALS, SETTING, METHODS: Using LC-MS/MS, we aimed to characterize androgen profiles and PCOS status in women with T1D, and interpret findings in relation to cohorts of non-diabetic women with and without PCOS. MAIN RESULTS AND THE ROLE OF CHANCE: Compared to non-diabetic women, dehydroepiandrosterone/dehydroepiandrosterone sulphate (DHEA/DHEAS) ratio was lower (P < 0.05) in women with T1D. Testosterone levels were greater in T1D women with clinical HA and anovulation compared to those without clinical HA and with regular cycles, while androstenedione levels were greater in T1D women with HA and anovulation compared to those with HA and regular cycles and also those without HA and with regular cycles (P < 0.05 for all). Compared to T1D women without PCOS, the 18% of T1D women who had PCOS were younger with lower BMI, an older age of menarche, and were more likely to have a positive family history of PCOS (P < 0.05 for all). Androgen levels did not differ between women with T1D and PCOS compared to BMI-matched non-diabetic women with PCOS, but androstenedione levels were greater in T1D women with PCOS compared to obese women with PCOS (P < 0.05). LIMITATIONS, REASONS FOR CAUTION: Relatively small subgroups of patients were studied, reducing the power to detect small differences. Free testosterone levels were not measured using equilibrium dialysis, and were not calculated - commonly used formulae have not been validated in T1D. WIDER IMPLICATIONS OF THE FINDINGS: Androstenedione is a sensitive biochemical marker of clinical hyperandrogenism and PCOS in T1D. T1D women with PCOS are leaner than those without PCOS but are more likely to have a family history of PCOS. Women with T1D and PCOS have a similar biochemical phenotype to lean non-diabetic women with PCOS but differ from obese women with PCOS. The mechanisms underlying PCOS in T1D and its clinical significance require further investigation. STUDY FUNDING/COMPETING INTEREST(S): The study was part-funded by the Meath Foundation. The authors have no competing interests.


Assuntos
Androgênios/sangue , Sulfato de Desidroepiandrosterona/sangue , Diabetes Mellitus Tipo 1/sangue , Testosterona/sangue , Adulto , Biomarcadores/sangue , Índice de Massa Corporal , Estudos de Casos e Controles , Cromatografia Líquida , Estudos Transversais , Diabetes Mellitus Tipo 1/complicações , Feminino , Humanos , Hiperandrogenismo/sangue , Hiperandrogenismo/complicações , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/complicações , Espectrometria de Massas em Tandem
7.
Dis Esophagus ; 30(6): 1-11, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28475745

RESUMO

Visceral obesity and metabolic syndrome (MetSyn) represent a constellation of inflammation, insulin resistance, and hyperglycemia and are established risk factors for gastrointestinal cancer. However, their impact on the immune and inflammatory response after major upper gastrointestinal oncologic surgery is unknown. In 125 consecutive patients who underwent esophagectomy, C-reactive protein (CRP) and CRP:albumin levels were recorded preoperatively and on days 1, 3, 7, and 14 postoperatively. In a subset of 30 patients, circulating levels of IL-6, IL-8, IL-10, IL-12p70, IFN-γ, TNF-α, TGF-ß, and cortisol were measured. Incidences of postoperative complications were prospectively recorded. In the study cohort, 51% of patients were viscerally obese, 40.7% had MetSyn, and 33.6% were hyperglycemic. Viscerally obese and MetSyn-positive patients demonstrated greater postoperative CRP levels and CRP:albumin levels on day 7 and day 14 compared with nonobese and MetSyn-negative patients (P < 0.05). Higher postoperative circulating levels of cortisol were observed in the viscerally obese and hyperglycemic patients compared to nonobese and normoglycemic patients. No association was observed between visceral obesity, MetSyn or hyperglycemia, and postoperative cytokine profile. Viscerally obese patients had an increased overall incidence of postoperative complications compared to nonobese patients (67.2% vs. 47.5%, P = 0.031) on univariate but not multivariate analysis (P = 0.078) and visceral obesity was not associated with an increased incidence of specific complications. Visceral obesity, MetSyn, and hyperglycemia are prevalent in patients undergoing major upper gastrointestinal resection and are associated with an exaggerated acute-phase inflammatory response postoperatively. Further research is warranted to determine whether this association is directly causal.


Assuntos
Adenocarcinoma/cirurgia , Neoplasias Esofágicas/cirurgia , Esofagectomia/efeitos adversos , Síndrome Metabólica/complicações , Obesidade Abdominal/complicações , Complicações Pós-Operatórias/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteína C-Reativa/análise , Citocinas/sangue , Feminino , Humanos , Hidrocortisona/sangue , Incidência , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/imunologia , Pessoa de Meia-Idade , Obesidade Abdominal/sangue , Obesidade Abdominal/imunologia , Complicações Pós-Operatórias/epidemiologia , Período Pós-Operatório , Período Pré-Operatório , Estudos Prospectivos , Estudos Retrospectivos , Albumina Sérica/análise , Resultado do Tratamento
8.
Clin Endocrinol (Oxf) ; 87(3): 257-263, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28425105

RESUMO

INTRODUCTION: Patients with microprolactinoma and idiopathic hyperprolactinaemia are not generally considered to be at risk of hypopituitarism and are therefore not routinely screened for this abnormality. In our clinical practice, we have observed a number of patients with nonmacroadenomatous hyperprolactinaemia to have anterior pituitary hormone deficits. AIMS: We aimed to establish the frequency and clinical significance of anterior pituitary hormone deficiencies, comparing patients with radiologically proven microprolactinomas and patients with idiopathic hyperprolactinaemia. STUDY DESIGN: We retrospectively examined the casenotes of 206 patients with hyperprolactinaemia from our centre. Patients who did not fit the profile of surgically naïve microprolactinoma or idiopathic hyperprolactinaemia or who had incomplete data were excluded, resulting in a study group of 56 patients. RESULTS: A total of 35 patients with MRI evidence of microprolactinoma were identified, three (8.57%) of whom had one or more anterior pituitary hormone deficiencies. A total of 21 patients with MRI-negative idiopathic hyperprolactinaemia were identified, nine (42%) of whom had one or more anterior pituitary hormone deficiencies (P<.01). Only one patient in the MRI-positive group had deficiency that required hormone replacement, in contrast six patients in the MRI-negative group had deficiencies that were of clinical significance and which required hormone replacement. SUMMARY: This study shows a clinically significant incidence of anterior pituitary hormone deficiency in patients with idiopathic hyperprolactinaemia. The authors recommend that dynamic pituitary assessment should be considered routinely in this patient group. A prospective study would be required to assess the underlying cause for these abnormalities, as they suggest a nontumour pan-pituitary process.


Assuntos
Hiperprolactinemia/complicações , Hormônios Adeno-Hipofisários/deficiência , Prolactinoma/complicações , Feminino , Terapia de Reposição Hormonal , Humanos , Hipopituitarismo , Incidência , Imageamento por Ressonância Magnética , Masculino , Estudos Retrospectivos
9.
QJM ; 110(7): 411-420, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-26873451

RESUMO

Acromegaly is a rare, chronic, progressive disease characterized by an excess secretion of growth hormone (GH) and increased circulating insulin-like growth factor 1 (IGF-1) concentrations. It is caused by a pituitary adenoma in the vast majority of cases. The clinical diagnosis, based on symptoms related to GH excess, is often delayed due to the insidious nature of the disease. Consequently, patients often have established systemic complications at diagnosis with increased morbidity and premature mortality. Serum IGF-1 measurement is recommended as the initial screen for patients with suspected acromegaly. The gold standard diagnostic test remains the oral glucose tolerance test with concomitant GH measurement. Therapy for acromegaly is targeted at decreasing GH and IGF-1 levels, ameliorating patients' symptoms and decreasing any local compressive effects of the pituitary adenoma. The therapeutic options for acromegaly include surgery, medical therapies (such as dopamine agonists, somatostatin receptor agonists and the GH receptor antagonist pegvisomant) and radiotherapy. A multidisciplinary approach is recommended with often a requirement for combined treatment modalities. With disease control, associated morbidity and mortality can be reduced. The recently published evidence-based guidelines by the Endocrine society addressed important clinical issues regarding the evaluation and management of acromegaly. This review discusses advances in our understanding of the pathophysiology of acromegaly, diagnosis of various forms of the disease and focuses on current treatment modalities, and on future pharmacological therapies for patients with acromegaly.


Assuntos
Acromegalia/diagnóstico , Acromegalia/fisiopatologia , Acromegalia/terapia , Terapia Combinada , Agonistas de Dopamina/uso terapêutico , Teste de Tolerância a Glucose , Hormônio do Crescimento/metabolismo , Hormônio do Crescimento Humano/análogos & derivados , Hormônio do Crescimento Humano/uso terapêutico , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Neoplasias Hipofisárias/complicações , Neoplasias Hipofisárias/patologia
10.
Artigo em Inglês | MEDLINE | ID: mdl-27933170

RESUMO

Meningioma growth has been previously described in patients receiving oestrogen/progestogen therapy. We describe the clinical, radiological, biochemical and pathologic findings in a 45-year-old woman with congenital adrenal hyperplasia secondary to a defect in the 21-hydroxylase enzyme who had chronic poor adherence to glucocorticoid therapy with consequent virilisation. The patient presented with a frontal headache and marked right-sided proptosis. Laboratory findings demonstrated androgen excess with a testosterone of 18.1 nmol/L (0-1.5 nmol) and 17-Hydroxyprogesterone >180 nmol/L (<6.5 nmol/L). CT abdomen was performed as the patient complained of rapid-onset increasing abdominal girth and revealed bilateral large adrenal myelolipomata. MRI brain revealed a large meningioma involving the right sphenoid wing with anterior displacement of the right eye and associated bony destruction. Surgical debulking of the meningioma was performed and histology demonstrated a meningioma, which stained positive for the progesterone receptor. Growth of meningioma has been described in postmenopausal women receiving hormone replacement therapy, in women receiving contraceptive therapy and in transsexual patients undergoing therapy with high-dose oestrogen and progestogens. Progesterone receptor positivity has been described previously in meningiomas. 17-Hydroxyprogesterone is elevated in CAH and has affinity and biological activity at the progesterone receptor. Therefore, we hypothesise that patients who have long-standing increased adrenal androgen precursor concentrations may be at risk of meningioma growth. LEARNING POINTS: Patients with long-standing CAH (particularly if not optimally controlled) may present with other complications, which may be related to long-standing elevated androgen or decreased glucocorticoid levels.Chronic poor control of CAH is associated with adrenal myelolipoma and adrenal rest tissue tumours.Meningiomas are sensitive to endocrine stimuli including progesterone, oestrogen and androgens as they express the relevant receptors.

11.
Artigo em Inglês | MEDLINE | ID: mdl-27252864

RESUMO

UNLABELLED: Avascular necrosis (AVN) is a rare presenting feature of endogenous hypercortisolism. If left untreated, complete collapse of the femoral head may ensue, necessitating hip replacement in up to 70% of patients. The majority of the described patients with AVN due to endogenous hypercortisolaemia required surgical intervention. A 36-year-old female, investigated for right leg pain, reported rapid weight gain, bruising and secondary amenorrhoea. She had abdominal adiposity with violaceous striae, facial plethora and hirsutism, atrophic skin, ecchymosis and proximal myopathy. Investigations confirmed cortisol excess (cortisol following low-dose 48h dexamethasone suppression test 807nmol/L; 24h urinary free cortisol 1443nmol (normal<290nmol)). Adrenocorticotrophic hormone (ACTH) was <5.0pg/mL. CT demonstrated subtle left adrenal gland hypertrophy. Hypercortisolaemia persisted after left adrenalectomy. Histology revealed primary pigmented micronodular adrenal disease. Post-operatively, right leg pain worsened and left leg pain developed, affecting mobility. MRI showed bilateral femoral head AVN. She underwent right adrenalectomy and steroid replacement was commenced. Four months after surgery, leg pain had resolved and mobility was normal. Repeat MRI showed marked improvement of radiological abnormalities in both femoral heads, consistent with spontaneous healing of AVN. We report a case of Cushing's syndrome due to primary pigmented nodular adrenocortical disease, presenting with symptomatic AVN of both hips. This was managed conservatively from an orthopaedic perspective. Following cure of hypercortisolaemia, the patient experienced excellent recovery and remains symptom free 4 years after adrenalectomy. This is the first report of a favourable outcome over long-term follow-up of a patient with bilateral AVN of the hip, which reversed with treatment of endogenous hypercortisolaemia. LEARNING POINTS: AVN of femoral head can be a presenting feature of hypercortisolism, both endogenous and exogenous.Rarely, treatment of hypercortisolaemia can reverse AVN without the need for orthopaedic intervention.Primary pigmented nodular adrenal disease is a rare cause of ACTH-independent Cushing's syndrome.

12.
Nat Commun ; 6: 8905, 2015 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-26563440

RESUMO

High-intensity lasers can be used to generate shockwaves, which have found applications in nuclear fusion, proton imaging, cancer therapies and materials science. Collisionless electrostatic shocks are one type of shockwave widely studied for applications involving ion acceleration. Here we show a novel mechanism for collisionless electrostatic shocks to heat small amounts of solid density matter to temperatures of ∼keV in tens of femtoseconds. Unusually, electrons play no direct role in the heating and it is the ions that determine the heating rate. Ions are heated due to an interplay between the electric field of the shock, the local density increase during the passage of the shock and collisions between different species of ion. In simulations, these factors combine to produce rapid, localized heating of the lighter ion species. Although the heated volume is modest, this would be one of the fastest heating mechanisms discovered if demonstrated in the laboratory.

13.
J Clin Endocrinol Metab ; 100(4): 1434-44, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25603461

RESUMO

CONTEXT: Tissue cortisol exposure is under the control of the isozymes of 11ß-hydroxysteroid dehydrogenase (11ß-HSD). 11ß-HSD1 in vivo, acts as an oxoreductase converting inactive cortisone to active cortisol. We hypothesized that 11ß-HSD1 activity is dysregulated in obesity and alters following bariatric surgery induced weight loss in different tissues. METHODS: We recruited 21 patients prior to undergoing bariatric surgery and performed cortisol generation profiles (following oral cortisone administration), urinary corticosteroid metabolite analysis, adipose tissue microdialysis, and tissue gene expression before and after weight loss, following bariatric surgery. Archived tissue samples from 20 previous bariatric surgery patients were also used for tissue gene expression studies. RESULTS: Gene expression showed a positive correlation with 11ß-HSD1 and BMI in omental adipose tissue (OM) (r = +0.52, P = .0001) but not sc adipose tissue (r = +0.28, P = .17). 11ß-HSD1 expression in liver negatively correlated with body mass index (BMI) (r = -0.37, P = .04). 11ß-HSD1 expression in sc adipose tissue was significantly reduced after weight loss (0.41 ± 0.28 vs 0.17 ± 0.1 arbitrary units, P = .02). Following weight loss, serum cortisol generation increased during a cortisol generation profile (area under the curve 26 768 ± 16 880 vs 47 579 ± 16 086 nmol/L/minute, P ≤ .0001.) Urinary corticosteroid metabolites demonstrated a significant reduction in total cortisol metabolites after bariatric surgery (15 224 ± 6595 vs 8814 ± 4824 µg/24 h, P = .01). Microdialysis of sc adipose tissue showed a threefold reduction in cortisol/cortisone ratio after weight loss. CONCLUSIONS: This study highlights the differences in tissue specific regulation of cortisol metabolism in obesity and after weight loss. Following bariatric surgery hepatic 11ß-HSD1 activity increases, sc adipose tissue 11ß-HSD1 activity is reduced and total urinary cortisol metabolites are reduced indicating a possible reduction in hypothalamic pituitary adrenal axis drive. 11ß-HSD1 expression correlates positively with BMI in omental adipose tissue and negatively within hepatic tissue. 11ß-HSD1 expression is reduced in sc adipose tissue after weight loss.


Assuntos
Cirurgia Bariátrica , Glucocorticoides/metabolismo , Obesidade Mórbida/metabolismo , Obesidade Mórbida/cirurgia , Redução de Peso/fisiologia , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/genética , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Glucocorticoides/urina , Humanos , Masculino , Microdiálise , Pessoa de Meia-Idade , Obesidade Mórbida/genética , Obesidade Mórbida/urina , Especificidade de Órgãos , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Gordura Subcutânea/química , Gordura Subcutânea/metabolismo
14.
Clin Endocrinol (Oxf) ; 82(1): 115-21, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24965315

RESUMO

OBJECTIVE: The incidence of hypopituitarism after aneurysmal subarachnoid haemorrhage (SAH) is unclear from the conflicting reports in the literature. As routine neuroendocrine screening for hypopituitarism for all patients would be costly and logistically difficult, there is a need for precise data on the frequency of hypopituitarism and on factors which might predict the later development of pituitary dysfunction. We aimed to: (i) Establish the incidence of long-term hypopituitarism in patients with aneurysmal SAH. (ii) Determine whether data from patients' acute admission with SAH could predict the occurrence of long-term hypopituitarism. DESIGN: One hundred patients were studied prospectively from the time of presentation with acute SAH. Plasma cortisol, plasma sodium and a variety of clinical and haemodynamic parameters were sequentially measured for the first 12 days of their acute admission. Forty-one patients then underwent dynamic pituitary testing at median 15 months following SAH (range 7-30 months), with insulin tolerance test (ITT) or, if contraindicated, a glucagon stimulation test (GST) plus short synacthen test (SST). If symptoms of cranial diabetes insipidus (CDI) were present, a water deprivation test was also performed. RESULTS: Forty-one patients attended for follow-up dynamic pituitary testing. Although 14 of 100 had acute glucocorticoid deficiency immediately following SAH, only two of 41 had long-term adrenocorticotrophic hormone (ACTH) deficiency and four of 41 had growth hormone (GH) deficiency. None were hypothyroid or gonadotrophin deficient. None had chronic CDI or hyponatraemia. There was no association between acute glucocorticoid deficiency, acute CDI or acute hyponatraemia and long-term pituitary dysfunction. CONCLUSION: Both anterior and posterior hypopituitarism are very uncommon following SAH and are not predicted by acute clinical, haemodynamic or endocrinological parameters. Routine neuroendocrine screening is not justified in SAH patients.


Assuntos
Hipopituitarismo/epidemiologia , Aneurisma Intracraniano/epidemiologia , Hemorragia Subaracnóidea/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Comorbidade , Feminino , Humanos , Hipopituitarismo/sangue , Aneurisma Intracraniano/sangue , Aneurisma Intracraniano/complicações , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Hemorragia Subaracnóidea/sangue , Hemorragia Subaracnóidea/etiologia , Sobreviventes , Adulto Jovem
15.
J Clin Endocrinol Metab ; 98(8): 3229-37, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23690314

RESUMO

CONTEXT: Published data demonstrates that hypopituitarism is common after traumatic brain injury (TBI). Hormone deficiencies are transient in many, but the natural history of the acute changes after TBI has not been documented. In addition, it is not clear whether there are any early parameters that accurately predict the development of permanent hypopituitarism. OBJECTIVES: There were 3 main objectives of this study: 1) to describe the natural history of plasma cortisol (PC) changes and sodium balance after TBI; 2) to identify whether acute hypocortisolemia or cranial diabetes insipidus (CDI) predict mortality; and 3) to identify whether the acute pituitary dysfunction predicts the development of chronic anterior hypopituitarism. DESIGN: Each TBI patient underwent sequential measurement of PC, plasma sodium, urine osmolality, and fluid balance after TBI. All other anterior pituitary hormones were measured on day 10 after TBI. The results from 15 surgical comparisons defined a PC less than 300 nmol/L as inappropriately low for an acutely ill patient. CDI was diagnosed according to standard criteria. Surviving TBI patients underwent dynamic anterior pituitary testing at least 6 months after TBI. SETTING: The patients were recruited from the Irish National Neurosurgery Centre. PATIENTS: One hundred sequential TBI patients were recruited. Fifteen patients admitted to Intensive Therapy Unit (ITU) after major surgery were recruited as comparison patients. MAIN OUTCOME MEASURES: PC in TBI patients was compared with that of comparison patients. The mortality rate was compared between TBI patients with and without acute hypocortisolemia. Results of follow-up dynamic pituitary testing were compared between those with and without acute hypocortisolemia. RESULTS: Most of the TBI patients (78%) developed inappropriately low PC after TBI. Low PC and CDI were predictive of mortality. Thirty-nine percent of the patients who had follow-up testing had at least 1 pituitary hormone deficit, all of whom had had previous acute hypocortisolemia or CDI. CONCLUSIONS: Acute hypocortisolemia and CDI are predictive of mortality and long-term pituitary deficits in TBI.


Assuntos
Lesões Encefálicas/complicações , Diabetes Insípido Neurogênico/etiologia , Glucocorticoides/deficiência , Doença Aguda , Adolescente , Hormônio Adrenocorticotrópico/deficiência , Adulto , Idoso , Idoso de 80 Anos ou mais , Lesões Encefálicas/mortalidade , Feminino , Hormônio do Crescimento Humano/deficiência , Humanos , Hidrocortisona/sangue , Masculino , Pessoa de Meia-Idade , Adeno-Hipófise/fisiopatologia
16.
Best Pract Res Clin Endocrinol Metab ; 25(5): 783-98, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21925078

RESUMO

Traumatic brain injury and subarachnoid haemorrhage are important causes of morbidity and mortality in the developed world. There is a large body of evidence that demonstrates that both conditions may adversely affect pituitary function in both the acute and chronic phases of recovery. Diagnosis of hypopituitarism and accurate treatment of pituitary disorders offers the opportunity to improve mortality and outcome in both traumatic brain injury and subarachnoid haemorrhage. In this article, we will review the history and pathophysiology of pituitary function in the acute phase following traumatic brain injury and subarachnoid haemorrhage, and we will discuss in detail three key aspects of pituitary dysfunction which occur in the early course of TBI; acute cortisol deficiency, diabetes insipidus and SIAD.


Assuntos
Lesões Encefálicas/fisiopatologia , Doenças da Hipófise/fisiopatologia , Hipófise/fisiopatologia , Hemorragia Subaracnóidea/fisiopatologia , Lesões Encefálicas/complicações , Lesões Encefálicas/terapia , Cuidados Críticos/tendências , Humanos , Sistema Hipotálamo-Hipofisário/fisiopatologia , Doenças da Hipófise/complicações , Doenças da Hipófise/etiologia , Doenças da Hipófise/terapia , Sistema Hipófise-Suprarrenal/fisiopatologia , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/terapia
17.
J Clin Endocrinol Metab ; 94(11): 4216-23, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19808848

RESUMO

CONTEXT: A number of retrospective studies report that patients with acromegaly have increased morbidity and premature mortality, with standardized mortality ratios (SMR) of 1.3-3. Many patients with acromegaly develop hypopituitarism as a result of the pituitary adenoma itself or therapies such as surgery and radiotherapy. Pituitary radiotherapy and hypopituitarism have also been associated with an increased SMR. METHODS: Using the West MIDLANDS: Acromegaly database (n = 501; 275 female), we assessed the influence of prior radiotherapy and hypopituitarism (and replacement therapy) on mortality in patients with acromegaly. Median duration of follow-up was 14.0 yr (interquartile range, 7.9-21 yr). RESULTS: All-cause mortality was elevated [SMR, 1.7 (1.4, 2.0); P < 0.001]. On external analysis, prior radiotherapy, ACTH, and gonadotropin deficiency were associated with an elevated SMR [radiotherapy SMR, 2.1 (1.7-2.6); P = 0.006; ACTH deficiency SMR, 2.5 (1.9-3.2); P < 0.0005; and gonadotropin deficiency SMR, 2.1 (1.6-2.7); P = 0.037]. On internal analysis, the relative risk (RR) of mortality was increased in the radiotherapy [RR, 1.8 (1.2-2.8); P = 0.008] and ACTH-deficiency groups [RR, 1.7 (1.2-2.5); P = 0.004], but not in the gonadotropin- or TSH-deficiency groups. In the ACTH-deficient group, increased replacement doses of hydrocortisone greater than 25 mg/d were associated with increased mortality compared to lower doses. CONCLUSIONS: Radiotherapy and ACTH deficiency are significantly associated with increased mortality in patients with acromegaly. In ACTH-deficient patients, a daily dose of more than 25 mg hydrocortisone is associated with increased mortality compared to lower doses. These results have important implications for the treatment of patients with acromegaly and also raise issues as to the optimum hydrocortisone treatment regimens for ACTH-deficient patients.


Assuntos
Acromegalia/complicações , Acromegalia/mortalidade , Hormônio Adrenocorticotrópico/deficiência , Hidrocortisona/uso terapêutico , Acromegalia/tratamento farmacológico , Acromegalia/radioterapia , Doenças Cardiovasculares/mortalidade , Causas de Morte , Feminino , Seguimentos , Terapia de Reposição Hormonal/efeitos adversos , Humanos , Masculino , Neoplasias/mortalidade , Valor Preditivo dos Testes , Radioterapia/efeitos adversos , Doenças Respiratórias/mortalidade , Fatores de Tempo
18.
Postgrad Med J ; 85(1002): 171-5, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19417163

RESUMO

BACKGROUND: Hyponatraemia is a well-recognised complication of neurosurgical conditions, but the incidence and implications have not been well documented. OBJECTIVE: To define the incidence, pathophysiology and clinical implications of significant hyponatraemia in several neurosurgical conditions. METHODS: All patients admitted to the Irish National Neurosciences Centre at Beaumont Hospital, Dublin with traumatic brain injury, subarachnoid haemorrhage, intracranial neoplasm, pituitary disorders and spinal disorders who developed significant hyponatraemia (plasma sodium <130 mmol/l) from January 2002 to September 2003 were identified from computerised laboratory records. Data were collected by retrospective case note analysis. RESULTS: Hyponatraemia was more common in patients with pituitary disorders (5/81, 6.25%; p = 0.004), traumatic brain injury (44/457, 9.6%; p<0.001), intracranial neoplasm (56/355, 15.8%; p<0.001) and subarachnoid haemorrhage (62/316, 19.6%; p<0.001) than in those with spinal disorders (4/489, 0.81%). The pathophysiology of hyponatraemia was: syndrome of inappropriate antidiuretic hormone secretion (SIADH) in 116 cases (62%) (31 (16.6%) drug-associated), hypovolaemic hyponatraemia in 50 cases (26.7%) (which included patients with insufficient data to assign to the cerebral salt-wasting group (CSWS)), CSWS in nine cases (4.8%), intravenous fluids in seven cases (3.7%) and mixed SIADH/CSWS in five cases (2.7%). Hyponatraemic patients with cerebral irritation had significantly lower plasma sodium concentrations (mean (SD) 124.8 (0.34) mmol/l) than asymptomatic patients (126.6 (0.29) mmol/l) (p<0.0001). Hyponatraemic patients had a significantly longer hospital stay (median 19 days (interquartile range (IQR) 12-28)) than normonatraemic patients (median 12 days (IQR 10.5-15)) (p<0.001). CONCLUSIONS: Hyponatraemia is common in intracerebral disorders and is associated with a longer hospital stay. Cerebral irritation is associated with more severe hyponatraemia. SIADH is the most common cause of hyponatraemia and is often drug-associated.


Assuntos
Doenças do Sistema Nervoso Central/cirurgia , Hiponatremia/etiologia , Procedimentos Neurocirúrgicos/efeitos adversos , Adulto , Idoso , Feminino , Humanos , Síndrome de Secreção Inadequada de HAD/etiologia , Masculino , Pessoa de Meia-Idade
19.
J Clin Endocrinol Metab ; 94(4): 1255-63, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19158203

RESUMO

CONTEXT: Acromegaly is associated with increased morbidity and mortality. Treatment options include surgery, radiotherapy, and medical therapy. AIMS: The objective of the study was to examine the role of prolactin status, prior surgery, and radiotherapy on the response to medical therapy in patients with acromegaly and assess the relative efficacy of dopamine agonist therapy compared with somatostatin analog therapy. MATERIALS AND METHODS: A total of 276 patients with acromegaly received either dopamine agonists (DA) and/or somatostatin analogs (SSA). One hundred seventy-two patients had received surgery and 73 radiotherapy prior to receiving medical therapy. One hundred ninety-eight of 276 received DA, and 143 of 276 received SSA. GH and IGF-I values at baseline and after 12 months on therapy were analyzed. RESULTS: In the DA group, basal prolactin concentration did not predict response to therapy, GH percent reduction: hyperprolactinemia, 26.7% (-10.4 to 48) vs. normoprolactinemia, 34.8% (0.2-53.2), P = 0.58; IGF-I percent reduction: hyperprolactinemia 30.0% (9.2-43.1) vs. normoprolactinemia 16.8% (4-37), P = 0.45. Prior surgery was not associated with any difference in response to DA: GH percent reduction (P = 0.1) and IGF-I percent reduction (P = 0.08). By contrast, prior radiotherapy was associated with an enhanced efficacy of GH response to DA, P = 0.02. In the SSA group, there was no effect of prior surgery or radiotherapy on response of GH, but radiotherapy was associated with less marked IGF-I percent reduction (P = 0.05). SSA were more potent than DA at decreasing both GH [62.8% (20.7-85%) vs. 42.4% (-6.5 to 68.6), P < 0.008] and IGF-I [SSA 40.4% (0-64.3) vs. 8% (0-40.8), P = 0.05]. CONCLUSIONS: The effects of DA are irrespective of baseline prolactin concentrations. Prior radiotherapy is associated with differences in GH and IGF-I response to DA and SSA therapy.


Assuntos
Acromegalia/sangue , Acromegalia/tratamento farmacológico , Agonistas de Dopamina/uso terapêutico , Somatostatina/análogos & derivados , Somatostatina/uso terapêutico , Acromegalia/radioterapia , Acromegalia/cirurgia , Hormônio Foliculoestimulante/deficiência , Hormônio do Crescimento Humano/sangue , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Hormônio Luteinizante/deficiência , Prolactina/sangue
20.
Clin Endocrinol (Oxf) ; 71(1): 74-81, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19178529

RESUMO

CONTEXT: The aims of treatment in patients with acromegaly are to achieve serum GH/IGF-I concentrations associated with cure or normalization of mortality and alleviation of symptoms. OBJECTIVE AND METHODS: Using the West Midlands Acromegaly database (n = 501) we investigated the reliability of basal fasting GH in predicting nadir or mean GH during oral glucose tolerance test (OGTT) or GH day curve (GHDC), respectively, the degree of discordance between disease activity measured by GH and IGF-I values and the effect of radiotherapy on the above relationships. In total 773 OGTT and 507 GHDC were performed. RESULTS: Basal fasting GH was strongly correlated with nadir/mean GH on OGTT/GHDC (r = +0.87, P < 0.0001, r = +0.93, P < 0.0001, respectively). A basal GH < 2.5 microg/l was associated with a nadir/mean GH during OGTT/GHDC < 2.5 microg/l in 98.6% and 88.2% of cases, respectively. Elevated IGF-I was seen in 32.4% and 46.4% of patients with GH nadir values during OGTT < 1 and < 2.5 microg/l, respectively, and in 21.2% and 45.9% of GHDC with mean GH < 1 and < 2.5 microg/l, respectively. Radiotherapy increased the discordance in GH and IGF-I as markers of disease activity at GH < 2.5 microg/l (elevated IGF-I-values when OGTT nadir GH < 2.5 microg/l: radiotherapy 55.5%vs. no radiotherapy 36.9%, P = 0.002). CONCLUSIONS: There is a close relationship between a basal fasting GH < 2.5 microg/l and nadir/mean GH < 2.5 microg/l during OGTT/GHDC. There is a large discordance between disease activity when assessed by GH and IGF-I which is further increased by radiotherapy. These observations illustrate the challenge of defining appropriate biochemical end-points to achieve control of disease and normalization of mortality in acromegaly.


Assuntos
Acromegalia/metabolismo , Hormônio do Crescimento Humano/sangue , Fator de Crescimento Insulin-Like I/análise , Acromegalia/diagnóstico , Acromegalia/terapia , Adulto , Feminino , Seguimentos , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica , Resultado do Tratamento , Adulto Jovem
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