[Molecular characterisation of a kindred with MEN2A and clinical implications]. / Caracterização molecular de uma família com nem2a e suas implicações clínicas.

INTRODUCTION: MEN2A is an autossomal dominant cancer syndrome characterised by the presence of medullary thyroid cancer, pheochromocytoma and primary hyperparathyroidism. Germline mutations of the RET protooncogene constitute the molecular defect and can be identified in affected individuals. Genetic screening of family members at risk allows early diagnosis and preventive measures before the appearance of the disease. We present a family with several members affected with MEN2A, their molecular characterisation and the clinical implications of genetic testing. POPULATION AND METHODS: We studied 18 members distributed among three generations of a family of which four members were clinically affected with MEN2A and cutaneous lichen amyloidosis. RET gene mutations were screened for in affected individuals and their offspring by PCR-RFLP techniques. RESULTS: Genetic testing revealed a point mutation at codon 634 (TGC>TGG), in the heterozygous state, in all affected individuals. The same mutation was also found in a five years old asymptomatic child which after total thyroidectomy showed to have multifocal medullary thyroid carcinoma. DISCUSSION: Genetic screening is the most suitable method for pre-symptomatic diagnosis of MEN2A allowing an efficient and early identification of individuals who will later develop the disease. These can be monitored more closely and be submitted to a prophylactic thyroidectomy before the appearance of medullary thyroid carcinoma. The ideal moment for this intervention is still under discussion although the results of this study suggest that it should be undertaken before the age of five.

[Autoimmune hypophysitis or lymphocytic hypophysitis]. / Hipofisite auto-imune ou linfocítica.

This entity, due to the pituitary lymphoplasmacytic infiltrate, was described for the first time in 1962. The clinical suspicion relies on a rapidly progressing hypopituitarism, particularly with adrenal involvement, affecting women in the peripartum period or patients with previously recognized autoimmune disease. Diabetes insipidus is also often reported. A sellar mass is found in 80% of cases. The diagnosis is confirmed by histology, due to the absence of a specific serological test. The endocrine deficiencies are frequently definitive. Corticotherapy is usually effective in reducing neurological symptoms due to pituitary enlargement, and frequently allows to avoid surgery. The disease-related deaths were due to acute adrenal insufficiency or ineffectively treated hypopituitarism. We are reporting a clinical case of probable lymphocytic hypophysitis in the early post partum of a woman with depression and Graves disease. She has hyperprolactinemia and ACTH deficiency, without pituitary changes in the magnetic resonance imaging. She was treated and her depression and hyperthyroidism were relieved. Hyperprolactinemia recovered spontaneously but she still needs glucocorticoid substitution.

[Radiotherapy of pituitary tumors]. / Radioterapia em tumores hipofisários.

The aim of this study is to evaluate the use of conventional external radiotherapy in patients with pituitary adenomas. Between October 1970 and May 1998, 27 patients with pituitary adenoma were followed at the Department of Endocrinology and Diabetes of the Hospitais da Universidade de Coimbra. They received radiation therapy at Instituto Português de Oncologia. Seven of those tumors were classified as nonfunctioning adenomas, 17 as growth-hormone-secreting adenomas, 2 as prolactinomas and 1 as adrenocorticotropic adenoma. Twenty-six patients received radiation as adjuvant therapy after incomplete resection and one patient as primary treatment. The majority of these cases were treated using the parallel opposed-field technique with a total dose between 45 and 52 Gy. The patients were submitted, before and after radiotherapy, to a protocol in order to assess the efficacy of this treatment. Some of the results were analyzed. Reduction of tumor mass was achieved in 66.6% of nonfunctioning tumors and in 25% of the secreting ones. Reduction or stabilization of hormonal levels was achieved in 55% of the cases and normalization in 30%. The average duration of follow-up was 126.3 months. Complications observed: hypopituitarism, stroke (3 patients), cerebral edema (1 patient), memory loss (2 patients) and hearing loss (2 patients). None of the patients developed brain tumors.

[Diabetic nephropathy. Study protocol for pre-kidney transplantation]. / Nefropatia diabética. Protocolo de estudo pré-transplantação renal.

Between May 1990 and October 1998, 67 diabetic patients with end-stage renal disease, on dialysis, were submitted to a standardized protocol in order to assess the coexistence and degree of other diabetic and nondiabetic complications that could affect transplantation. Some of the results were analysed. Type 2 diabetic patients had more abnormal results on the lower limbs doppler ultrasound and on the lower limbs arteriography than type 1 (p < 0.05). Type 2 diabetic patients had more cardiovascular complications so the decision to transplant should be taken on a case by case basis.

Mutational analysis of Portuguese families with multiple endocrine neoplasia type 1 reveals large germline deletions.

OBJECTIVE: To determine the spectrum of MEN1 mutations in Portuguese kindreds, and identify mutation-carriers. PATIENTS, DESIGN AND RESULTS: Six unrelated MEN1 families were studied for MEN1 gene mutations by single-strand conformational polymorphism (SSCP) and DNA sequence analysis of the coding region and exon-intron boundaries of the MEN1 gene. These methods identified 4 different heterozygous mutations in four families: two mutations are novel (mt 1539 delG and mt 655 ims 11 bp) and two have been previously observed (mt 735 del 46p and mt 1656 del C) all resulting in a premature stop codon. In the remaining two families, in whom no mutations or abnormal MEN1 transcripts were detected, segregation studies of the 5' intragenic marker D11S4946 and codon 418 polymorphism in exon 9 revealed two large germline deletions of the MEN1 gene. Southern blot and tumour loss of heterozygosity analysis confirmed and refined the limits of these deletions, which spanned the MEN1 gene at least from: exon 7 to the 3' untranslated region, in one family, and the 5' polymorphic site D11S4946 to exon 9 (obliterating the initiation codon), in the other family. Twenty-six mutant-gene carriers were identified, 6 of which were asymptomatic. CONCLUSIONS: These results emphasize the importance of the detection of MEN1 germline deletions in patients who do not have mutations of the coding region. Important clues indicating the presence of such deletions may be obtained by segregation studies using the intragenic polymorphisms D11S4946 and at codon 418. The detection of these mutations will help in the genetic counselling of clinical management of the MEN1 families in Portugal.

[Acute thyroiditis]. / Tiroidites agudas.

We review the pathophysiology, clinical features and therapy of acute thyroiditis. Four cases are reported stressing the role of fine needle aspiration for the diagnosis of this clinical entity.

The hyperparathyroidism-jaw tumour syndrome in a Portuguese kindred.

The hyperparathyroidism-jaw tumour (HPT-JT) syndrome is an autosomal dominant disease characterized by the occurrence of parathyroid tumours and fibro-osseous tumours of the jaw bones. Some HPT-JT patients may also develop renal abnormalities, which include Wilms' tumours, hamartomas and polycystic disease. The HPT-JT gene has been mapped to chromosome 1q25-q31, and we report the clinical and genetic findings in a kindred from central Portugal. HPT-JT was observed in six members from three generations; all had primary hyperparathyroidism (five had parathyroid adenomas, one a parathyroid carcinoma). Ossifying jaw fibromas affecting the maxilla and/or mandible were observed in 5/6. Renal cysts (<2.5 cm) were observed in four. Genetic studies using 18 polymorphic loci from chromosome 1q25-q31, together with leukocyte DNA from 11 family members and tumour DNA from three parathyroids (two adenomas and one carcinoma), revealed loss of tumour heterozygosity in the parathyroid carcinoma only, and the retained haplotype was found to cosegregate with the disease in the six affected members. A new Portuguese kindred with the HPT-JT syndrome that maps to chromosome 1q25-q31 has been identified, and these findings will help in the further characterization of this inherited disorder.

[deficiency of growth hormone in children. Re-evaluation after therapeutic completion]. / Deficiência de GH nas crianças. Reavaliação após conclusão terapêutica.

OBJECTIVE: To assess GH secretion in young adults treated with GH replacement therapy in childhood. PATIENTS AND METHODS: From the 38 patients who concluded treatment with GH, we studied 20 (52.6%), 9 girls and 11 boys. Thirteen had Growth Hormone Deficiency (GHD)-65%, while 7 had Multiple Pituitary Hormone Deficiency (MPHD)-35%. The patients were retested within 6 months to 6 years after completing GH therapy. The mean age (+/- SD) at retesting was 18.1 +/- 2.6 years for those with GHD and 20.8 +/- 2.8 for those with MPHD. At reassessment we performed two provocative tests: insulin tolerance test (ITT) and clonidine test. RESULTS: Seven of the 20 patients retested, retained GH deficiency. Of the 13 patients with GHD, only one maintained the deficiency, while of the 7 patients with MPHD, 6 maintained the deficiency. CONCLUSION: Young adults with GH deficiency treated with this hormone should be retested in order to identify those who are truly GH insufficient adults and may benefit from replacement therapy.

[Kidney transplantation in patients with type I and type II diabetes mellitus]. / Transplantação renal em doentes com diabetes mellitus tipo I e tipo II.

A total of 618 patients with end-stage renal disease received kidney transplants between 1980 and September 1996. Twenty eight of them were diabetics. Better results were achieved for type 1 diabetic patients than for type 2 (mortality: 5.9% vs 27.3%; functioning graft: 88.2% vs 72.7%). The morbility was also higher in those patients (infections: 81.8% vs 29.4%; vascular complications: 45.5% vs 17.6%). Actuarial patient and graft survival were lower for type 2 than for non diabetic patients. For type 1 diabetics the results are similar to those for non diabetics. Better results can probably be achieved by restricting the selection criteria. The decision to transplant or maintain on dialysis should be made on a case by case basis.

[Craniocerebral imaging in children with short stature]. / Imagiologia crânio-encefálica nas crianças com baixa estatura.

OBJECTIVE: To analyse the type and frequency of cranial CT and NMR imaging anomalies in children of short stature. PATIENTS AND INTERVENTIONS: We studied 57 children of short stature with a mean age (+/-SD) of 10.1 +/- 3.8 years, 34 boys and 23 girls, all of them with auxometric criteria of GH deficiency. After studying the pituitary function and determination of karyotype in the girls, the children were classified in to five groups:-Isolated GHD (IGHD) (n = 32), multiple pituitary hormone deficiency (MPHD) (n = 6), neurosecretory dysfunction (NSD) (n = 8), Turner syndrome (n = 7) and idiopathic short stature (ISS) (n = 4). The imaging methods used were cranial CT or NMR. RESULTS: Of the 57 children studied the CT/NMR was abnormal in 37(64.9%) children. We found anomalies in 65.6% of IGHD patients, 62.5% of NSD patients, 100% of MPHD patients and 57.1% and 25% in the Turner s. patients and ISS patients respectively. The most frequent anomaly was hypoplastic pituitary found in 50% of IGHD patients, 37.5% of NSD patients and 33.3% of MPHD patients. None of the cases of Turner s. or ISS had hypoplastic pituitary. An empty sella was the second most frequent anomaly found in 7 patients (IGHD-3, MPHD-3, DNS-1). Of the 25 children in which NMR was performed, 8 had hypoplastic pituitary and stalk and 2 had interruption of the pituitary stalk and ectopic neurohypophysis. CONCLUSION: These results strengthen the necessity for CT/NMR imaging in children of short stature which, besides allowing identification of tumors, also permits the diagnosis of idiopathic GHD because of its frequent association with cranial imaging anomalies, mainly hypoplastic pituitary.

[The prevalence of hypertension in acromegaly]. / Prevalência da HTA na acromegália.

AIM: To estimate the prevalence of hypertension (HT) in a group of patients with acromegaly at the moment of diagnosis and after treatment. PATIENTS AND METHODS: Fifty-seven patients, 43 females and 14 males with a mean age of 45.19 +/- 11.9 years were studied retrospectively. In the last visit 9 patients (15.7%) were in remission and 47 (84.2%) had active acromegaly. We considered hypertensive the patients with systolic BP > or = 140 and/or diastolic BP > or = 90 mmHg. Hypertension was classified in four stages:- mild, moderate, severe and very severe. RESULTS: The prevalence of hypertension at the moment of diagnosis was 35%. The hypertensive patients had a mean age of 51.75 +/- 9.3 years and normotensive patients 41.65 +/- 11.6 years (p < 0.001). In females the prevalence of HT was 27.9% and in males it was 57% (p = NS). In hypertensive patients (n = 20), the mean BP was 159 +/- 15 (syst.)/97.2 +/- 9.8 (diast.), 16 patients (80%) had mild to moderate HT and the remainder had severe (n = 2) and very severe (n=1) HT. In the last visit, 22.2% of patients were cured and 46.8% of those with active acromegaly were hypertensive. None of the patients cured and initially normotensive developed HT; among those that were hypertensive (n = 3), 2 remained hypertensive and 1 became normotensive. Among patients with active acromegaly and initially normotensive, 7 developed HT 4.85 +/- 2.03 years later; of those hypertensive at diagnosis (n = 16), only one became normotensive. The last case was 27 years old. The patients that remained hypertensive had a mean age of 53.8 +/- 6.85 years (41-62 years). CONCLUSIONS: The prevalence of hypertension at the moment of diagnosis was 35%, similar to the majority of studies published and higher than the general population. The hypertensive patients were significantly older the normotensive patients and most of them had mild to moderate HT. We observed an increase in the prevalence of HT over the years in the cases that maintained active acromegaly. In our series only one of the three patients cured became normotensive, therefore, we concluded that HT in acromegaly is frequently irreversible. The chances of normalization seems higher in younger patients and probably with a shorter duration of acromegaly.

Characterization and regulation of glycine transport in Fusarium oxysporum var. lini.

Glycine was transported in Fusarium oxysporum cells, grown on glycine as the sole source of carbon and nitrogen, by a facilitated diffusion transport system with a half-saturation constant (Ks) of 11 mM and a maximum velocity (Vmax) of 1.2 mM (g dry weight)-1 h-1 at pH 5.0 and 26 degrees C. Under conditions of nitrogen starvation, the same system was present together with a high-affinity one (Ks) of about 47 microM and Vmax of about 60 microM (g dry weight)-1 h-1). The low-affinity system was more specific than the high-affinity system. Cells grown on gelatine showed the same behavior. In cells grown on glucose-gelatine medium, the low-affinity system was poorly expressed even after carbon and nitrogen starvation. Moreover, addition of glucose to cells grown on glycine and resuspended in mineral medium caused an increase of the glycine transport probably due to a boost in protein synthesis. This stimulation did not affect the Ks of the low-affinity system. These results demonstrate that, as is the case for other eukaryotic systems, F. oxysporum glycine transport is under control of nitrogen sources but its regulation by carbon sources appears to be more complex.

Characterization and regulation of glycine transport in Fusarium oxysporum var. lini

Glycine was transported in Fusarium oxysporum cells, grow on glycine as the sole source of carbon and nitrogen, by a facilitated diffusion transport system with a half-saturation constant(Ks) of 11 mM and a maximum velocity (Vmax) of 1.2 mM (g dry weight)-1 h-1 at pH 5.0 and 26 degrees Celsius. Under conditions of nitrogen starvation, the same system was present together with a high-affinity one(Ks) of about 47 muM and Vmax of about 60 muM (g dry weight)(-1) h-1)). The low-affinity system was more specific than the high-affinity system. Cells grown on gelatine showed the same behavior. In cells grown on glucose-gelatine medium, the low-affinity system was poorly expressed even after carbon and nitrogen starvation. Moreover, addition of glucose to cells grown on glycine and resuspended in mineral medium caused an increase of the glycine transport probably due to a boost in protein synthesis. This stimulation did not affect the Ks of the low-affinity system. These results demonstrate that, as is the case for other eukaryotic systems, F.oxysporum glycine transport is under control of nitrogen sources but its regulation by carbon sources appears to be more complex.

[Beneficial effects of added glicazide in patients with type II diabetes mellitus treated with insulin]. / Efeitos benéficos da adição de gliclazida em doentes diabéticos do tipo II sob insulina.

The aim of the study was to assess, in patients with non insulin dependent diabetes mellitus (NIDDM), either with previous failure to sulphonylureas or insulin treated since the disease started, if the combination of gliclazide to insulin therapy might induce a reduction of daily insulin requirement. 30 caucasian type II patients used to self-monitoring (11 female, 19 male, mean age 55.78 +/- 8.07) with residual pancreatic function (glucagon induced C-peptide release = 1.01 +/- 0.70 microgram/ml) entered the study. 8 were excluded for non compliance or for high antiinsulin antibodies levels and 4 are still under study. Each patients was given, for 3 months, 240 mg of gliclazide in addition to usual daily dose of insulin. Data presented as mean +/- s.e.m. were analysed with analysis of variance (p less than 0.05). Mean initial values of main parameters were as follows: glycaemia 192.7 +/- 33.1 mg/100 ml, insulinaemia 9.5 +/- 4.5 microUI/ml, daily insulin requirements 33.11 +/- 10.47 U/d, HbA1 C 7.5 +/- 1.7%. Total cholesterol 240.1 +/- 52.2 mg/10 ml, triglycerides 120.6 +/- 60.3 mg/100 ml. After 3 months treatment significant reduction in mean daily insulin requirements (20.78 +/- 16.15 U/d) was observed. In 13 patients (72.2%) while keeping good metabolic control (HbA1 C 7.46 +/- 1.63), insulin therapy was reduced (9 patients) or even stopped (4 patients). In the other 5, insulin was maintained or slightly increased. The increase in glucagon induced C-peptide release (1.41 +/- 0.99 micrograms/ml) did not reach significance, while glycaemia and insulinaemia were not changed (196.0 +/- 34.1 mg/100 ml, 11.02 +/- 5.05 microUI/ml).(ABSTRACT TRUNCATED AT 250 WORDS)