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J Evanson

Publications and source records attributed to J Evanson.

12 recordsLinked to original sources
PubMed2003

The relationship between pituitary tumour transforming gene (PTTG) expression and in vitro hormone and vascular endothelial growth factor (VEGF) secretion from human pituitary adenomas.

OBJECTIVE: Pituitary tumour transforming gene (PTTG) is a recently identified protooncogene, ubiquitously expressed in pituitary tumours at levels higher than those detected in normal pituitary. Although the precise function of PTTG protein is unknown, in vitro experiments have shown that it induces angiogenesis. In this study, we have examined the potential relationship between the level of PTTG expression and tumour phenotype, tumour size, in vitro pituitary hormone secretion and release of vascular endothelial growth factor (VEGF), a potent angiogenic factor. METHODS: Pituitary tumours (12 somatotroph, five lactotroph, five corticotroph and 18 non-functioning) were studied by cell culture, measuring the basal secretion of anterior pituitary hormones and VEGF in vitro. Immunocytochemistry was used to confirm the clinical diagnosis and tumour phenotype. PTTG mRNA expression was investigated by comparative RT-PCR. Tumour Volume was quantitated from pre-operative MRI scans. RESULTS: PTTG expression was significantly increased 2.7-fold in somatotroph tumours compared with non-functioning adenomas (P<0.01, ANOVA). A positive correlation was demonstrated between PTTG expression and in vitro GH secretion (r=0.41, P<0.01, Spearman) but no correlations were found for any of the other pituitary hormones. In 16 out of 40 pituitary tumours, we were able to determine the in vitro secretion of VEGF and relate this to PTTG expression. All of the adenomas tested secreted measurable VEGF but there was no correlation between the amount of VEGF secreted and either the tumour phenotype or PTTG expression. Neither PTTG expression nor VEGF secretion correlated with tumour Volume. CONCLUSIONS: Our studies have confirmed the presence of PTTG in pituitary adenomas and demonstrated a higher level of expression in somatotroph tumours and a significant correlation with GH secretion. We failed to demonstrate a relationship between PTTG expression and production of the angiogenic factor, VEGF, or tumour Volume. Thus, although PTTG induces angiogenesis experimentally, it seems unlikely that a VEGF-mediated angiogenic mechanism occurs during pituitary tumour progression.

Adenoma↗
PubMed2002

Idiopathic familial temporal lobe epilepsy with febrile convulsions.

Efforts to duplicate the genetic and molecular breakthroughs of autosomal dominant frontal lobe epilepsy have lead to increased interest in familial temporal lobe epilepsy. In this report we describe three kindreds. The epilepsy syndrome described manifests after the teenage years and was generally mild and treatment responsive. The predominant seizure types were simple and complex partial seizures, typical of mesial temporal onset. Some family members had febrile convulsions only and others had epilepsy without preceding febrile convulsions. Three patients had both febrile convulsions and temporal lobe epilepsy. High-resolution quantitative and qualitative MRI was normal. The syndrome in these three kindreds is distinct from temporal lobe epilepsy due to mesial temporal sclerosis and febrile convulsions and is probably a form of idiopathic localization related epilepsy. Its relation to other familial temporal lobe epilepsy phenotypes is discussed.

Adolescent↗
PubMed2001

Pituitary chondrosarcoma: an unusual cause of a sellar mass presenting as a pituitary adenoma.

A 37-yr-old woman with clinical, endocrinological, and radiological features suggestive of a nonfunctioning pituitary tumor was found to have a chondrosarcoma of the pituitary sella. The bony structures around the sella were relatively uninvolved, other than showing minor erosion of the left side of the dorsum and the posterior wall of the sphenoid sinus. After partial resection of the tumor by the transsphenoidal route the patient received postoperative radiosurgery by a linear accelerator, stereotactic multiarc radiotherapy. Subsequent follow-up revealed reduction of the residual tumor. This case demonstrates that a chondrosarcoma may apparently arise directly from the pituitary fossa and suggests the efficacy of stereotactic radiosurgery, at least in the medium term. The origin, areas of involvement, management, and long-term prognosis of these rare tumors are reviewed.

Adenoma↗
PubMed2001

Hypothalamo-pituitary surveillance imaging in hypopituitary patients receiving long-term GH replacement therapy.

Most cases of adult-onset (AO) GH deficiency (GHD) result from the presence of hypothalamo-pituitary tumors or their treatment. GH replacement is now widely used in adults with hypopituitarism, but its effect on hypothalamo-pituitary tumor growth or recurrence is unknown. Anecdotal evidence from early experience of GH replacement in adults documented occasional tumor recurrence, but any relationship of this to the use of GH was unclear. We have now prospectively imaged the pituitary glands of 100 consecutive patients (60 females, 40 males; mean age, 46 yr; range, 18-69 yr) who had AO-GHD after appropriate treatment for a pituitary or peripituitary tumor. External radiotherapy had been given to 91 patients. All patients were treated with a dose titration regimen to maintain serum IGF-I between the median and upper end of the age-related reference range. Pituitary imaging was performed before the commencement of GH and after 6 and 12 months of treatment in all patients, again at 2 yr in 92 patients, at 3 yr in 63 patients, and after 4 yr in 23 patients. In only one patient was there evidence of slight intrasellar tissue enlargement at 6 months; GH replacement was continued, and there was no further change between 6 and 12 months. In all other patients, either the appearances were unchanged or the amount of tissue was reduced during long-term follow-up on GH. We have shown that hypothalamo-pituitary tumor recurrence was thus very rare over this time period in this group of GH-treated patients, and this is reassuring. Similar prospective longitudinal observation of patients who have not received postoperative irradiation and comparison with rates of tumor recurrence in control series are desirable.

Adenoma↗
PubMed2001

Relative contributions of inferior petrosal sinus sampling and pituitary imaging in the investigation of children and adolescents with ACTH-dependent Cushing's syndrome.

Selective transsphenoidal microadenomectomy is the first line treatment of childhood Cushing's disease, with accurate preoperative localization of the corticotroph adenoma an important step in its investigation. Inferior petrosal sinus sampling (IPSS) for ACTH after CRH stimulation is a recognized investigation in adults, but there are few data in the pediatric age range. We report the relative contributions of IPSS and pituitary imaging in 11 patients, aged 10.7-18.8 yr, presenting with Cushing's disease. All underwent transsphenoidal surgery (TSS). IPSS was performed without complication. Sampling was from the inferior petrosal sinuses in 7 patients and the high jugular veins in 4 (patients 2, 4, 5, and 10). The central to peripheral ACTH (IPS/P) ratios were more than 2 (2.5-157.2) in 10 of 11 patients, confirming central ACTH secretion. In 3 patients with high jugular sampling, IPS/P ratio ranged from 2.5-21.1. In the fourth patient with high jugular sampling (IPS/P ratio, 0.95), a central adenoma was identified surgically, and the patient was cured after TSS. The interpetrosal sinus ACTH gradient (IPSG) was more than 1.4 (2.1-20.8) in 10 patients, indicating lateralization of ACTH secretion to the right side in 6 patients and to the left in 4. IPSG ratios were 2.1-8.5 in 3 patients with high jugular sampling. Pituitary imaging (computed tomography and or magnetic resonance imaging) was reported to identify an adenoma in 5 of 11 patients. At operation a tumor was visualized by the same surgeon in all 11 cases. In 9 patients with lateralization on IPSS, the correct side of the tumor was confirmed at surgery. In a 10th patient with a negative IPSG, a central tumor was present. Thus, IPSS gave a 91% prediction of correct tumor localization. In only 1 of 5 patients with an adenoma reported on pituitary imaging was this localization confirmed at surgery, a prediction rate of only 9%. After TSS, 8 patients were cured, 1 was in remission, and 2 required pituitary irradiation. In 73% of patients undergoing IPSS, localization of the adenoma was followed by surgical cure or remission. Pituitary scanning was therefore relatively unhelpful in localizing the adenoma. In experienced hands, however, IPSS was feasible in this age group, safe, and strongly predictive of the site of the adenoma, leading to a high rate of successful surgical outcome.

Adenoma↗
PubMed2000

Hypothalamo-pituitary abnormalities in adult patients with langerhans cell histiocytosis: clinical, endocrinological, and radiological features and response to treatment.

Langerhans cell histiocytosis (LCH) is a rare disorder in which granulomatous deposits occur at multiple sites within the body, but which often involves the hypothalamo-pituitary axis (HPA). Although diabetes insipidus (DI) is a well recognized complication, the frequency of anterior pituitary and other nonendocrine hypothalamic (NEH) involvement has not been well defined, particularly in adult patients with the disease. We have evaluated the frequency and progression of LCH-related anterior pituitary and other NEH dysfunction and their responses to treatment in 12 adult patients with histologically proven LCH and DI. They were followed up for a median of 11.5 yr (range, 3-28 yr) after the diagnosis of DI was made. Study evaluations comprised clinical (including formal psychometric assessment where appropriate), basal and dynamic pituitary function tests, and radiology with computed tomography and/or magnetic resonance imaging scanning. Eleven patients received systemic treatment, and 5 patients received external beam radiotherapy confined to the HPA. The median age at diagnosis of DI was 34 yr (range, 2-47 yr); DI was the presenting symptom in four patients, whereas the remaining eight each developed DI 1-20 yr (median, 2 yr) after the diagnosis of LCH. Eight patients developed one or more anterior pituitary hormonal deficiencies at a median of 4.5 yr (range, 2-22 yr) after the diagnosis of DI: GH deficiency developed in eight patients (median, 2 yr; range, 2-22 yr), FSH-LH deficiency in 7 patients (median, 7 yr; range, 2-22 yr), and TSH and ACTH deficiency in five patients (median, 10 yr; range, 3-16 and 3-19 yr), respectively; five patients developed panhypopituitarism. In addition, seven patients with anterior pituitary dysfunction also developed symptoms of other NEH dysfunctions at a median of 10 yr (range, 1-23 yr): five morbid obesity (body mass index, >35), five short term memory deficits, four sleeping disorders, two disorders of thermoregulation, and one adipsia. All patients developed disease outside of the hypothalamus during the course of the study, and no fluctuation of disease activity in the HPA region was noted. Radiological examination of the HPA was abnormal in each of the eight patients with anterior pituitary involvement and in the seven patients with NEH dysfunction (one or more abnormalities): seven had thickening of the infundibulum, and one had hypothalamic and thalamic signal changes. All patients who had a magnetic resonance imaging scan had absence of the bright spot of the posterior pituitary on the T1-weighted sequences, and in four patients with DI and normal anterior pituitary function this was the only abnormality. The five patients who received radiotherapy to the HPA achieved a partial or complete radiological response, and there was no evidence of tumor progression in this region. No form of therapy, including chemotherapy, improved any established hormonal deficiencies or symptoms of NEH. In summary, in our adult patients with hypothalamic LCH and DI, anterior pituitary hormonal deficiencies developed in 8 of 12 patients; these occurred over the course of 20 yr. They were frequently accompanied by structural changes of the HPA, although these were often subtle in nature. In addition, symptoms of NEH dysfunction developed in up to 90% of such patients and complicated management. Radiotherapy may be useful in achieving local control of tumor, but established anterior, posterior pituitary, and other NEH dysfunctions do not improve in response to current treatment protocols. Patients with LCH and DI, particularly those with multisystem disease and a structural lesion on radiology, should undergo regular and prolonged endocrine assessment to establish anterior pituitary deficiency and provide appropriate hormonal replacement.

Adolescent↗
PubMed1999

Central nervous system sarcoidosis--diagnosis and management.

A series of 68 patients with neurosarcoidosis is reported, with particular emphasis on clinical aspects, diagnosis and treatment. A classification system based on clinical diagnostic probability is proposed, consisting of probable and definite disease, the latter being dependent on finding sarcoid granulomas on nervous system histology, which was obtained in 12 patients (18%). The role of investigations, including magnetic resonance imaging (MRI), chest radiography, Kveim skin test, Gallium 67 isotope scanning and cerebrospinal fluid (CSF) studies, is considered. Sixty-two percent of patients presented with nervous system disease, most commonly affecting the optic nerve and chiasm. Other common presentations included cranial nerve palsies, spinal cord and brainstem manifestations. Investigations yielding most diagnostic information included the Kveim test (41/48, 85% positive), raised CSF protein and/or cells (50/62, 81%) and gallium 67 scan (14/31, 45%). Eleven out of 29 patients (38%) patients showed meningeal enhancement on MRI scanning and 43% of scans demonstrated multiple white-matter lesions. Mean follow-up for the group was 4.6 years. Forty-seven patients were seen for > 18 months, and over half of these patients progressed despite corticosteroid and other immunosuppressive therapies. The benefit of a large patient database prospectively studied, with extended follow-up is discussed in order to learn more about prognosis and advance therapy in neurosarcoidosis.

Adrenal Cortex Hormones↗
PubMed1999

Risk factors for hospitalization in well-dialyzed chronic hemodialysis patients.

BACKGROUND/AIMS: Hemodialysis (HD) patients are hospitalized more frequently than patients with other chronic diseases, averaging 11.5 hospital days/patient/year. Hospital costs attributable to renal failure in the US exceed $2 billion per year. The present healthcare climate continues to force dialysis providers to focus on these issues in order to optimize patient care while limiting cost. METHODS: We used a novel method for analyzing hospitalization risk, a multiple-event Cox proportional hazards model, to identify factors that influenced hospitalization in a HD unit population over a two-year period. This model allows individual patients to contribute multiple failure events to the model while controlling for the serial dependency of events. RESULTS: 178 HD patients were retrospectively examined. There were 381 hospitalizations during the study period, averaging out to 1.9 hospitalizations and 10.5 hospital days/patient-year. Substance abuse and diabetes conveyed the largest risks for hospitalization (diabetes RR: 2.09; substance abuse RR: 2.24) in the study cohort, exposing the necessity for examining practice patterns and behavioral interventions as means for improving HD patient care. CONCLUSION: Despite the small numbers of patients in this single-center HD population, the model achieved adequate statistical power. Therefore, it has the potential to serve as a continuous quality improvement (CQI) tool in particular HD patient sub-groups, or in individual HD units.

Female↗
PubMed1996

The effectiveness of papilledema as an indicator of raised intracranial pressure in children with craniosynostosis.

Craniosynostosis management partially depends on the detection and treatment of elevated intracranial pressure (ICP). Examination for papilledema is considered to be the most reliable screening method for identifying raised ICP, but its effectiveness has not been defined. One hundred and twenty-two children with craniosynostosis who underwent funduscopic examinations and then Camino ICP monitoring were studied. All eye examinations were performed by an ophthalmologist after pharmacological pupillary dilation. Fifteen patients (12%) had papilledema. Subsequent ICP monitoring showed that the median ICP was 12.7 mm Hg, with 41 patients (34%) having elevated ICPs (> 15 mm Hg). Those with papilledema had higher ICPs (17.5 +/- 3.2 versus 12.7 +/- 5.5 mm Hg), were older (5.9 +/- 4.7 versus 1.9 +/- 2.6 years), and were more likely to have craniofacial syndromes (73 versus 41%) than those without papilledema (P < 0.05). Patients with both elevated ICPs and papilledema were older (5.9 +/- 4.7 versus 1.6 +/- 1.4 years) and more likely to have multiple-suture synostosis (92 versus 61%) than those with elevated ICPs and no papilledema (P < 0.05). The presence of papilledema was a specific (98%) indicator of raised ICP, but its sensitivity was age-dependent. It was 100% sensitive in children older than 8 years, but it indicated elevated ICP in only 22% of younger patients. These results suggest that ICP monitoring to document elevated ICP is unnecessary in children older than 8 years who have detailed ophthalmological examinations. In the younger child, the presence of papilledema reliably indicates elevated ICP but its absence does not rule out elevated ICP; formal ICP measurement has a greater role in detecting elevated ICP in these patients.

Adolescent↗
PubMed1996

The beaten copper cranium: a correlation between intracranial pressure, cranial radiographs, and computed tomographic scans in children with craniosynostosis.

OBJECTIVE: The beaten copper appearance of the cranium, as well as other cranial radiographic and computed tomographic findings in children with craniosynostosis, is often interpreted by clinicians as evidence of elevated intracranial pressure (ICP). However, a correlation between radiological findings and ICP measurements has not been previously demonstrated, and their usefulness in detecting elevated ICP has not been defined. METHODS: To address those issues, 123 children with craniosynostosis who had cranial radiographs and ICP monitoring were studied. To assess the specificity of certain radiological findings to patients with craniosynostosis, cranial radiographs of patients with craniosynostosis were compared to those of age- and sex-matched controls. In patients with craniosynostosis, findings on cranial radiographs were compared to computed tomographic scans of the brain. Radiographic findings were then correlated with ICP measurements obtained while the patient was sleeping, which was measured using a Camino fiberoptic ICP monitor (Camino Laboratories, San Diego, CA). All radiographs were independently analyzed by two radiologists who were blinded to clinical and ICP data. RESULTS: A diffuse beaten copper pattern, erosion of the dorsum sellar, and suture diastasis were seen more commonly in patients with craniosynostosis than in controls (P < 0.05), but the presence of the beaten copper pattern was no more common in children with craniosynostosis. ICP was greater when a diffuse beaten copper pattern, dorsum sellar erosion, suture diastasis, or narrowing of basal cisterns was present (P < 0.05). CONCLUSION: Although this study demonstrates that some cranial radiographic and computed tomographic findings do correlate with elevated ICP, the sensitivity of radiological methods for detecting elevated ICP is universally low and they are not recommended to screen for elevated ICP in children with craniosynostosis.

Child↗