The clinical picture and surgery of pheochromocytomas. Our experience over 25 years]

The pheochromocytoma syndrome, caused by an abnormal secretion of catecholamines, is a rare pathology responsible for 0.1-2% cases of hypertension in the overall population considered. Although in the past we deemed the pheochromocytoma could cause prevalently the typical syndrome characterized by paroxysmal hypertensive crises, now we think that the usual clinical presentation is a continue or subcontinue hypertensive state (65%). In this paper the authors refer the clinical experience acquired in 25 years in the General and Cardiovascular Institute of the University of Milan (head: Prof. Ugo Ruberti), analyzing epidemiological aspects and pathogenesis of pheochromocytoma, with particular care to diagnostic methodologies and referring the therapeutic choices. From 1965 until today 40 patients have been surgically treated for pheochromocytoma mono or bilateral. 43 operations have been done, carrying out 46 adrenalectomy. Two complication must be referred: an ictus cerebri consequent upon an hypertensive crisis and one death caused by intraoperative ventricular fibrillation. Normalization of arterial pressure has been obtained in all patients.     

Thyroid carcinoma mimicking a toxic adenoma

A young woman with a thyroid papillary carcinoma behaving as an autonomously hyperfunctioning nodule is described. Only 17 similar patients have been seen in the past 25 years. It is emphasized that hyperthyroidism does not exclude malignant disease in hot nodules. This possibility suggests that all thyroid nodules, either cold or hot, require careful management. Therefore, in at risk cases, surgery could be the most useful treatment.     

Estrogen Deprivation and Myocardial Infarction: Role of Aerobic Exercise Training,Inflammation and Metabolomics

In general, postmenopausal women present higher mortality, and worse prognosis after myocardial infarction (MI) compared to men, due to estrogen deficiency. After MI, cardiovascular alterations occur such as the autonomic imbalance and the pro-inflammatory cytokines increase. In this sense, therapies that aim to minimize deleterious effects caused by myocardial ischemia are important. Aerobic training has been proposed as a promising intervention in the prevention of cardiovascular diseases. On the other hand, some studies have attempted to identify potential biomarkers for cardiovascular diseases or specifically for MI. For this purpose, metabolomics has been used as a tool in the discovery of cardiovascular biomarkers. Therefore, the objective of this work is to discuss the changes involved in ovariectomy, myocardial infarction, and aerobic training, with emphasis on inflammation and metabolism.     

Arterial diseases of surgical importance. Long-term control of diet-related risk factors

From 1980 to 1990 a yearly medical-surgical control was carried out on 950 arteriopathic patients hospitalised in the General and Cardiovascular Surgery Institute, Milan University, during the above mentioned period. The operations for surgical reconstruction were mainly for arteriosclerotic lesions involving the abdominal-peripheral district (750 patients, 79%) and the supra aortic trunks (200 patients, 21%). 84% of the patients were males. Among the patients on follow-up, a relatively modest number (100 patients) did not attend the prescribed diet therapies for several reasons, consequently these patients have been considered as a control group. The comparison, between the patients who attended and those who did not attend the diet, has been made on the basis of the following parameters: cholesterolemia (COL), LDL, HDL, triglyceridemia (TG), VLDL, glycemia (GLI), body mass index (BMI) and arterial pressure (PA). The results have shown a decrease in the absolute normal values of cholesterol, LDL and triglycerides, while they have not shown the same significant variations regarding glycemia and body weight. In accordance with the literature, the diet seems to have obtained satisfactory results, especially regarding the values of lipidemia, with a reduction in the atherogenic risk index. Regarding smoke as a risk factor it has been shown that it is present in 80% of the patients at the beginning: 60% of the patients stop smoking at the moment they are hospitalised and the remaining 20% continue smoking. The hygienic-dietetic intervention is confirmed, also in our experience, as a curative, or even more, a preventive tool against the worsening of an already overt arteriosclerosis as well as a necessary support for drug therapies.     

Thermal assembly of a biomimetic mineral/collagen composite

A strategy is described for exploiting temperature driven self-assembly of collagen and thermally triggered liposome mineralization to form a mineralized collagen composite from an injectable precursor fluid. Optical density and rheological experiments demonstrated the formation of a collagen gel when acid-soluble type I collagen solutions (1-7 mg/ml) were heated to 24-30 degrees C. Scanning calorimetry experiments demonstrated that mixtures of calcium- and phosphate-loaded liposomes composed of dipalmitoylphosphatidylcholine (90 mol%) and dimyristoylphosphatidylcholine (10 mol%) were stable at room temperature but formed calcium phosphate mineral when heated above 35 degrees C, a consequence of the release of entrapped salts at the lipid chain melting transition. The formation of calcium phosphate mineral induced by triggered release of calcium and phosphate was detected as an endothermic transition (deltaH=6.2+/-1.1 kcal/mol lipid) near the lipid chain melting transition (Tm=37 degrees C). Combining an acid-soluble collagen solution with calcium- and phosphate-loaded liposomes resulted in a liposome/collagen precursor fluid, which when heated from room temperature to 37 degrees C formed a mineralized collagen gel. The dynamic storage modulus of the collagen scaffold increased upon mineralization, and direct nucleation of mineral from the collagen scaffold was detected by electron microscopy.     

Neoplastic thrombosis of the inferior vena cava and right atrium due to kidney cancer. Three surgically treated cases

Extension into vena cava and right atrium of tumor thrombus from a renal cell carcinoma presents a surgical challenge. The use of cardiopulmonary by-pass, hypothermia and cardiac arrest with temporary exsanguination has allowed the successful surgical excision of this tumor. During 1986 and 1987 3 patients with cancer of kidney invading the vena cava were operated on with this surgical technique. No deaths occurred. The possibility of curing this type of cancer with minimal operative risk and good results is discussed.     

Antigen processing by epidermal Langerhans cells correlates with the level of biosynthesis of major histocompatibility complex class II molecules and expression of invariant chain

Two prior studies with a small number of T cell lines have shown that the presentation of native protein antigens by epidermal Langerhans cells (LC) is regulated. When freshly isolated, LC are efficient antigen-presenting cells (APC), but after a period of culture LC are inefficient or even inactive. The deficit in culture seems to be a selective loss in antigen processing, since cultured LC are otherwise rich in major histocompatibility complex (MHC) class II products and are active APC for alloantigens and mitogens, which do not require processing. We have extended the analysis by studying presentation to bulk populations of primed lymph node and a T-T hybrid. Only freshly isolated LC can be pulsed with the protein antigens myoglobin and conalbumin, but once pulsed, antigen is retained in an immunogenic form for at least 2 d. The acquisition of antigen, presumably as MHC-peptide complexes, is inhibited if the fresh LC are exposed to foreign protein in the presence of chloroquine or cycloheximide. The latter, in contrast, improves the efficacy of antigen pulsing in anti-Ig-stimulated B blasts. In additional studies of mechanism, we noted that both fresh and cultured LC endocytose similar amounts of an antigen, rhodamineovalbumin, into perinuclear granules. However, freshly isolated LC synthesize high levels class II MHC molecules and express higher amounts of the class II-associated invariant chain. Fresh LC are at least 5-10 times more active than many other cells types in the level of biosynthesis of MHC class II products. These findings provide a physiologic model in which newly synthesized MHC class II molecules appear to be the principal vehicle for effective antigen processing by APC of the dendritic cell lineage. Another APC, the B lymphoblast, does not appear to require newly synthesized MHC class II molecules for presentation.