Robertsonian translocations are the most frequent structural chromosomal abnormalities in humans and can affect fertility, with various degrees of sperm alterations in men; or the pregnancy outcome of the carriers. The studies on meiotic segregation of chromosomes in sperm of Robertsonian translocation males find a majority of normal or balanced spermatozoa for the chromosomes related to the translocation (mean 85.42%; range 60–96.60%). Furthermore, recent studies suggest an interchromosomal effect. Studies on spermatozoa from translocation carriers, and in mouse models help the comprehension of the meiotic segregation mechanisms. Results of meiotic segregation analysis in man could be integrated in genetic counselling especially when assisted reproductive technology is required.
A 51-year-old woman consulting within the framework of investigation for abdominal discomfort, nausea, and vomiting underwent a computed tomography examination that revealed a well-delimited right adrenal heterogeneous mass measuring 8.2 × 8.3 cm with a native density of 40 Hounsfield units (HU)8. An 18F-deoxyglucose positron emission tomography scan showed a hypercaptation on the adrenal tumor of 7.4 SUVmax. Apart from these symptoms, the patient had no other complaint. Familial history was unremarkable. On examination, the patient was in good physical condition, arterial blood pressure was 136/85 mmHg, heart rate at 74 bpm.
The measurement of plasma renin activity and aldosterone and the results of a 1-mg overnight dexamethasone suppression test ruled out primary hyperaldosteronism and Cushing syndrome. Catecholamine and metanephrine concentrations in multiple blood and urine samples were consistently within the reference interval and not compatible with the diagnosis of a pheochromocytoma (Table 1).
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Table 1.
Concentrations of renin, aldosterone, cortisol, catecholamine, and their metabolites in urine and plasma found in the patient.a
Because the adrenal mass was not hormonally active, its surgical resection was performed without preoperative care. The removal of a mass weighing 356 g in the right adrenal gland was performed by open laparotomy.
Histopathological analysis of tissue sections of the adrenal mass yielded an unexpected result: a pheochromocytoma was diagnosed on the basis of typical well-arranged nests called zellballen. This encapsulated adrenal tumor exhibits a low proliferation index (MIB-1, 1%–2%; 1 mitosis/high power field) without vascular invasion. Immunohistochemistry of the tumor sections revealed its neuroendocrine feature, with cells highly expressing CD56, chromogranin A, NSE, synaptophysin, and vimentin. Unfortunately, blood samples obtained before surgery were collected on heparin-coated tubes precluding serum chromogranin A assay. Because the unusual presentation of a “non–catecholamine-secreting pheochromocytoma” was in complete contradiction with the biochemical feature expected for these tumors, we …
Scarce knowledge of vascular rare diseases, defined by prevalence lower than 1/2000, is accompanied by increased patients mis-management and impaired quality of life. Recent advances in clinical knowledge, molecular biology, and genetic evaluation of certain vascular rare diseases allows designing new management strategies. A tight coordinated collaboration between angiologists and other specialists is therefore necessary to optimize patient's care.
Hypophosphatasia is a rare inherited disorder characterized by defective bone mineralization and deficiency of serum and liver/bone/kidney-type alkaline phosphatase (L/B/K ALP) activity. We report the characterization of tissue-nonspecific alkaline phosphatase (TNSALP) gene mutations in a series of 12 families affected by severe or mild hypophosphatasia. Twenty distinct mutations were found, 5 of which were previously reported. Nine of the 15 new mutations were missense mutations (T117N, A159T, R229S, A331T, H364R, D389G, R433H, N461I, and C472S). The others were 2 nonsense mutations (L-12X and E274X), one single nucleotide deletion (1256delC), 2 mutations affecting splicing (298-2A>G, 997+2T>A), and a mutation in the major transcription start site (-195C>T). Hum Mutat 15:293, 2000.
