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Biomedical subjects

G Bisogno

Publications and source records attributed to G Bisogno.

24 records · Page 2Linked to original sources

Defective platelet aggregation in response to platelet-activating factor in uremia associated with low platelet thromboxane A2 generation.

The bleeding tendency associated with uremia is likely due to a qualitative platelet dysfunction. So far the data available on platelet aggregation are conflicting. Since platelet-activating factor (PAF) plays a role in primary hemostasis, we studied platelet aggregation in response to PAF in 40 patients with chronic uremia on regular hemodialysis and 12 control subjects. Our results showed that in 28 of 40 uremics, platelet aggregation response to PAF was normal, whereas in the remaining 12 it was defective in that no second wave of aggregation was elicited even if the PAF concentrations were increased by a factor of 10,000. This abnormal response was peculiar to PAF and only partially related to factor(s) of plasma origin. The number of platelet PAF receptors and their affinity for the agonist were comparable in controls and "PAF-unresponsive" patients. The defective platelet aggregation in response to PAF was associated with a statistically significant reduction (P less than 0.01) in thromboxane A2 (TxA2) generation in platelet-rich plasma (PRP) challenged with PAF (10 and 100 nmol/L). When PRPs from PAF-unresponsive patients were preincubated with a stable analogue of prostaglandin endoperoxides/TxA2 U-46619, an irreversible platelet aggregation in response to PAF was obtained. Thus in a subpopulation of uremics, platelet aggregation in response to PAF is selectively abnormal as a consequence of a reduced TxA2 generation.

Adult↗

Platelet activating factor (PAF) as a mediator of injury in nephrotoxic nephritis.

Release of acetyl glyceryl ether phosphorylcholine, platelet-activating factor (PAF), has been demonstrated to be associated with glomerular inflammatory damage in acute serum sickness. Moreover, PAF can increase glomerular permeability to proteins and induce mesangial contraction. Thus PAF might be a good candidate as a mediator of glomerular damage. However the in vivo evidence that PAF might cause glomerular injury is lacking. To evaluate if PAF has a major role in promoting glomerular inflammatory reaction and fibrin deposition, we studied the effect of a molecule, L-652,731, which blocks the PAF receptor, on the evolution of an experimental model of anti-glomerular basement membrane (anti-GBM) glomerulonephritis (GN). GN was initiated by sheep-anti-rabbit nephrotoxic serum. A proliferative GN regularly occurred in which heavy proteinuria, intra and extracapillary proliferation of resident and inflammatory cells and fibrin deposition in Bowman's capsule were the prominent findings. Our results showed that the PAF receptor antagonist reduces the glomerular damage in anti-GBM GN, supporting the hypothesis that PAF is indeed a mediator of glomerular inflammatory reaction. PAF receptor blocking prevented renal function deterioration in the early phase of the disease, probably preserving glomerular hemodynamics. In the delayed phase of the disease the PAF receptor antagonist reduced proteinuria and prevented renal function deterioration and fibrin deposition. These effects appear to be mediated by an inhibitory action of PAF receptor blocking on macrophage accumulation and activation.

Animals↗

[Chemotherapy in fibromatoses of childhood and adolescence: results from the Cooperative soft tissue sarcoma study (CWS) and the Italian Cooperative study group (ICG-AIEOP)].

BACKGROUND: Fibromatoses are a group of semimalignant tumors which grow infiltratively without metastases. If radical surgery is not at all possible or only by mutilation the question of neoadjuvant concepts arises. PATIENTS: We report on therapy and outcome of 36 patients registered to the German CWS study group and the Italian ICG study group for soft tissue sarcoma who were between 0 and 23 years of age. 15 had a histology of infantile (myo-) fibromatosis (9 unifocal, 6 multifocal). 15 patients had desmoid-like, aggressive fibromatosis. METHODS: We performed a retrospective analysis of the patients registered to the CWS and ICG study group. For literature review a medline search was performed. RESULTS: 23 patients received chemotherapy with anthracyclines (VAIA) or without (VAC) or monotherapy with alkylating agents. In 19 cases response to chemotherapy was measurable. In 9 patients tumors responded to chemotherapy. In some cases response was evident only after 20 weeks of treatment. In the group of non responders treatment was stopped early (after 4 weeks) in some cases. Relapses occurred mainly in the group of desmoid-like, aggressive fibromatosis (7 out of 15). In the group of infantile (myo-) fibromatosis only one patient suffered a relapse (1 out of 9). The literature review showed that mainly ADR/DTIC, VAC and MTX/VBL was used for inoperable fibromatoses. Concerning the response rates there where no major differences. Concerning toxicity the regimen with methotrexate and vinblastine seems superior to the others. CONCLUSIONS: As a chemotherapy regimen of first choice vinblastine with low dose methotrexate can be recommended. The therapy should not be stopped before the 20th week of treatment. The histological subgroup can provide good information on the relapse rate and aggressivity to be expected.

Adolescent↗

Rhabdomyosarcoma in a patient with cardio-facio-cutaneous syndrome.

A boy with characteristic facial features, pulmonary valvular stenosis, ectodermal abnormalities, growth failure, and mental retardation was admitted for intestinal occlusion at 20 months of age. Clinical findings were consistent with a diagnosis of cardio-facio-cutaneous syndrome (CFC-s), and a huge abdominal mass was evident on computed tomography scan. A biopsy was performed, and embryonal rhabdomyosarcoma was diagnosed. Molecular analysis was performed by reverse transcription (RT) polymerase chain reaction (PCR) on tumor RNA to seek the chimerical transcript of the most common soft tissue sarcoma translocations and analyze neurofibromatosis 1 (NF1) gene expression. Translocations involving 1;13, 2;13, and 11;22 were not found, and the specific transcripts of the NF1 gene were present. Chemotherapy was implemented, but the child died 7 months later of tumor progression. Few patients with CFC-s have been described, and their follow-up is not well known. The association of CFC-s with rhabdomyosarcoma has not been reported previously, but other neoplasms have been reported in patients with Noonan syndrome, a condition similar to CFC-s. More observations are needed, but this and other reports suggest there could be a higher risk of malignancy in patients with syndromes in the Noonan phenotype category.

Adult↗

[Soft tissue sarcoma in childhood: local treatment in patients under 3 years of age. Analysis of the RMS-88 multicenter study].

The purpose of this report is to describe the treatment and the outcome of patients affected by soft tissue sarcomas and enrolled in the Italian Cooperative Study RMS 88, whose age was less than 36 months. In particular the role of local treatment is discussed, considering that RT was not recommended by the protocol. The 104 patients, 70 affected by RMS and 34 by NR-STS, were grouped according to the Intergroup Rhabdomyosarcoma Staging (IRS) system. The general guidelines of the study for the local treatment included surgery in Gr I, surgery + radiotherapy (40 Gy) in Gr II, surgery (1 or more procedures) + radiotherapy (45-54 Gy) in Gr III, but RT was not recommended for patients < 3 years. RMS: The 5 patients in Gr I did not receive RT: 4/5 are alive NED and 1 is lost at FU. Among the 5 patients in Gr II, 5 did not receive RT and are alive NED; 4 were given RT and 2 of these died of disease. In the 56 patients in Gr III, RT was utilized in 25: 5 died of disease and 6 manifested distant sequelae due to RT. 10/31 patients who were not given RT, did not undergo any other local treatment and died of disease; 4 patients died after surgery only. NRSTS: 7/9 Gr I patients are alive (1 was treated with RT and did not present sequelae); 1/9 died and 1 is lost at FU. 3/6 Gr II patients are alive (1 after RT), 2 died of disease and 1 is lost at FU. 2/19 Gr III patients were given RT and 1 died of disease; 3 of the not irradiated patients died without any local treatment, 4 after surgery only. CONCLUSION: The local treatment was important for patients' outcome: only 28% of the RMS and 36% of the NRSTS patients who were not treated with surgery a/o RT are in CR. Surgery was not particularly aggressive (6 mutilating procedures). RT was utilized in 33/104 patients and sequelae were 7. The difference in overall survival between patients less than 3 and patients more than 3 is not statistically significant.

Child, Preschool↗

[Role of mutilating surgery in the treatment of non-chemosensitive pediatric soft tissue sarcomas. Experience of the Italian Cooperative Group Studies RMS-79 and RMS-88].

UNLABELLED: Aim of the study was to evaluate the role of mutilating surgery in the patients with non chemosensitive soft tissue sarcomas (STS) registered in the Italian Studies. Between 1979 and 1995, 114 patients (pts) with "non chemosensitive" localized STS were enrolled in the cooperative studies RMS-79 (33) and RMS-88 (81). Median age: 89 months (range 1-194). HISTOLOGY: fibrosarcoma 29, Malignant Perpheral Nerve Sheath Tumors (MPNST) 40, malignant fibrous histiocytoma 5, hemangiopericytoma 6, leiomyosarcoma 4, others 20, STS nos 10. The cases were classified according to the IRS staging system as Gr. I 46, Gr. II 24, Gr. III 44. Twelve out of 114 pts (7%), 5/33 (14%) in the first study and 7/81 (8%) in the second, underwent mutilating surgery: 8 pts (of whom 3 were < 2 y of age) had a fibrosarcoma and 4 a MPNST. The mutilating procedure was carried out at diagnosis in 6 cases (4 in RMS-79 and 2 in RMS-and 88) and achieved radicality in 5/6 cases. It was performed after ineffective chemotherapy (CT) in 5 pts (1 in RMS-79 and 4 in RMS-88). One pt (RMS-88) underwent mutilation after multiple local recurrences treated with CT, radiotherapy and conservative excisions (RMS-88) and died. The procedures consisted of 5 amputations, 4 demolitive excisions of extremities with functional impairment, 1 nephrectomy, 1 excision of deferents with spermatic vesicae and 1 mastectomy. OUTCOME: At present 6/12 pts, 5 with fibrosarcoma and 1 with MPNST, are alive with no evidence of disease (NED), 4 of the first and 2 of the second study. Of the 5 Gr. I patients, 4 are alive (NED) and 1 died of 2nd tumor; 1 Gr. II pt is alive NED; of the 5 Gr. III pts 1 is alive NED and 4 died (3 of metastatic spread and 1 of 2nd tumor); the pt amputated after repeated local relapses (Gr. II) is dead of pulmonary metastases. CONCLUSIONS: In the RMS-79 study the mutilations were frequent and were performed at diagnosis in several cases; this trend decreased in the 2nd study in which chemotherapy was attempted in most of the patients. Probably the timing of mutilating procedures was not always adequate (too early or too late). The outcome of pts undergone mutilations is similar to that of the whole group of 114 pts, whose overall survival at 10 years is 64% (C.I. 60-77). Only fibrosarcomas and MPNST probably requires a more aggressive surgical behaviour. At present we avoid initial demolitive surgery; it should be planned without delay after the first local relapse or after initial ineffective CT and RT.

Adolescent↗