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L Bergamaschini

Publications and source records attributed to L Bergamaschini.

At least 37 records · Page 2Linked to original sources

Haemostasis contact system and fibrinolysis in hereditary angioedema (C1-inhibitor deficiency).

Factors of the classical complement pathway, the contact system and fibrinolysis were evaluated both with functional and immunochemical methods, in patients with inherited deficiency of C1-inhibitor. Evaluations were performed under basal conditions, during acute attacks and during prophylaxis with low doses of anabolic steroids. Patients in the basal state showed no significant abnormalities of any of the parameters that we investigated. During acute attacks a slightly reduced prekallikrein concentration was registered. During treatment with low doses of danazol and stanozolol, protein C and plasminogen were found to be increased. Our data suggest that C1-inhibitor deficiency per se does not lead to a derangement of the fibrinolysis and coagulation contact system, and that the kinin system may be involved during acute attacks of angioedema.

Adolescent↗

Immunoreactive precipitation of C1 inhibitor protein from plasma of normal subjects and of patients with hereditary angioedema after isoelectric focusing.

C1-inhibitor is an acid glycoprotein, isoelectric point 3.5-3.6. Plasma of some patients with a variant form of hereditary angioedema contains high levels of functionless C1-inhibitor-albumin complex with an isoelectric point at 4.5-4.6. Therapy with Danazol, which increases C1-inhibitor levels, does not modify the isoelectric focusing pattern of such protein in patients with hereditary angioedema.

Adult↗

Acquired C1 inhibitor deficiency with angioedema symptoms in a patient infected with Echinococcus granulosus.

A patient with echinococcosis, acquired deficiency of the inhibitor of the activated first component of complement and angioedema symptoms has been studied. These symptoms started 7 months after the surgical removal of an echinococcus liver cyst. Eight years later, when the complement was investigated, a marked deficiency of the C1 inhibitor, C1, C4 and CH50 was present. The patient was therefore successfully treated with tranexamic acid. After 4 years, the woman needed another operation because of a relapse of echinococcosis; afterwards she was symptom-free without medications, while the complement profile remained unchanged. Circulating immune complexes were detected by the conglutinin method. The patient's serum was demonstrated to possess an anticomplementary activity without affecting the C1 inhibitor when incubated with normal human serum at 37 degrees C. At present, 16 years after the onset of the symptoms, there are no signs of lymphoproliferative disease.

Angioedema↗

Studies of complement activation in ARDS patients treated by long-term extracorporeal CO2 removal.

To investigate the role of complement activation in the adult respiratory distress syndrome (ARDS) and in the complications of extracorporeal circulation (ECC), several parameters (CH50, C3 split products, C3a, C5a, PMN aggregating activity, carboxypeptidase activity) of the complement profiles of 23 ARDS patients were measured. Twenty patients were treated by long-term extracorporeal support. Before connection to ECC, marked leukocytosis (18,250 +/- 5,950) and significantly high plasma C3a levels (p less than 0.005) were observed. After connection, C3a levels increased further, up to values eight times higher than the basal ones. The WBC count transiently decreased to 41% of prebypass levels after 15 minutes of ECC. At the same time C3 split products appeared and PMN aggregating activity was shown in 52% of the patients. C5a levels remained normal during bypass, even in two samples in which PMN aggregating activity was detected. Later decreases in CH50 titers (p less than 0.001) and carboxypeptidase activity (p less than 0.005) were observed. Complement activation was no longer evident after the 24th hour of bypass. We conclude that there is a low-degree complement activation in ARDS, and ECC is a further strong stimulus for complement activation. This phenomenon appears, however, to be self-limited.

Adolescent↗

Morphologic evaluation of the liver in hereditary angioedema patients on long-term treatment with androgen derivatives.

17 alpha-Alkylated androgens are highly effective in preventing attacks in HAE patients. These drugs, however, seem to be implicated in the development of cholestatic jaundice, peliosis hepatis, and liver tumors. In order to assess the risk-benefit balance of the long-term therapy with androgen derivatives, a follow-up investigation was performed in 13 HAE patients. The results of this study indicate that long-term treatment (15 to 47 mo) with low doses of danazol or stanozolol does not induce significant hepatic damage detectable by laboratory tests or liver biopsy. However, the limited number of patients, although in a rather long period of observation, still suggests a careful control and the use of minimal effective doses.

Adult↗

Effect of treatment with 17 alpha-alkylated androgens on C4 conversion products in hereditary angioedema studied by crossed immunoelectrophoresis.

During agarose electrophoresis C4 in the normal human serum is converted into cleavage products of Beta 1 and Beta 2 mobility. By contrast in the serum of untreated patients with hereditary angiodema C4 gives only one Beta 2 peak on crossed immunoelectrophoresis. The normal C4 electrophoretic pattern is restored in serum of patients treated with stanazolol but not with danazol despite the same C1-esterase inhibitor (C1 INH) activities and C4 serum concentration. We suggest that stanazolol besides having specific effect on C1 INH activity can interfere with other protease inhibitors affecting C1 activation.

Adult↗

[Pathological effects of recently isolated complement derived peptides].

The C3a and C5a polypeptides release, under conditions of complement activation, causes a change in PMN shape and adhesiveness with formation of leukoemboli in microvascular districts. Those modified granulocytes produce oxygen radicals with toxic activity. This mechanism seems to play a role in different pathological situations like pulmonary distress in hemodialysis, leukapheresis, cardiopulmonary by-pass and extent of necrosis in acute myocardial infarction. The same mechanism has been largely investigated in Adult Respiratory Distress Syndrome (A.R.D.S.). In this condition the leukoembolization toxicity seems to be the most important pathogenetic factor of the alveolo-capillary membrane damage which is the base of the disease.

Animals↗

Pityriasis rubra pilaris and and retinol-binding protein.

Serum levels of retinol-binding protein (the specific carrier of vitamin A) were measured in eleven patients with pityriasis rubra pilaris and in some of their close relatives. The level of retinol-binding protein was markedly reduced in every patient, and in some of the relatives. It is postulated that defective synthesis of retinol-binding protein is a biochemical marker for pityriasis rubra pilaris, probably transmitted as a Mendelian dominant.

Adolescent↗

Danazol and stanozolol in long-term prophylactic treatment of hereditary angioedema.

Treatment with 17 alpha-methyltestosterone and with some synthetic androgens prevents attacks of hereditary angioedema (HAE). However, the potential hepatotoxicity of 17 alpha-alkylated androgens raises the problem of long-term prophylactic use of these agents. Therefore we compared the efficacy in preventing HAE attacks of 17 alpha-alkylated steroids (danazol and stanozolol) with non-17 alpha-alkylated derivatives (quinbolone, nandrolone decanoate and mesterolone). As the latter group proved ineffective, it seems that a drug's efficacy in preventing HAE attacks is connected to its 17 alpha-alkylation. Moreover, our long-term observations with the minimum effective dose of danazol seem to indicate the absence of important collateral effects.

Adult↗