Biomedical subjects

A Bonomo

Publications and source records attributed to A Bonomo.

32 records · Page 2Linked to original sources

PubMed1994

Premature escape of double-positive thymocytes to the periphery of young mice. Possible role in autoimmunity.

Thymectomy of 3-day-old mice induces organ-specific autoimmune disease. To define a relationship between the development of T cells early in the neonatal period and autoimmunity, we studied the thymus and peripheral lymphoid tissues of 3-day-old mice. Lymph nodes, but not spleens, of 3- to 4-day-old mice contained a significant number of thymus-derived CD4+CD8+ cells that are phenotypically similar to CD4+CD8+ thymocytes in their level of expression of CD3 and HSA. It is likely that the prematurely exported cells are the progenitors of autoreactive T cells because the lymph nodes from 3- to 4-day-old male, but not female, mice which express a transgenic TCR specific for the H-Y Ag contained a large number of CD4+CD8+Tg+ as well as CD4-CD8+Tg+ T cells. Thus, the neonatal thymus is capable of exporting immature T cells that in the absence of a thymus may differentiate into autoimmune effector cells.

Animals↗

PubMed1994

[Axillo-femoral bypass in the treatment of aorta prosthesis infection. A special case].

The authors report a case recently brought to their observation: T.A., a 77 year old patient, operated on in July 1990, for aortic aneurysm with axillo femoral by-pass. The patient was reoperated on the 5th day for ischaemic necrosis of the descending colon. In 1992 he was operated in another hospital for right iliac branch removal of the by-pass and performing of extra-anatomic bifemoral by-pass for right iliac branch infection of anatomic prosthesis. He was brought to our observation in March 1993, after the patient was refused in other Centres because of purulent abscess located near the aortic prosthesis and in the right iliac fossa, with a fistula to right superior anterior iliac crista. The patient was operated on in April 1993, with an explorative laparatomy to drain the abscess and to remove the aortic prosthesis. The aorta was sutured with closed bottom by means of delayed points. The postoperative course was regular and an arteriography performed three months after confirms the good running of the axillo-femoral by-pass and of the bifemoral one previously performed. The authors because of their experience and the bibliographical data underline the goodness of the axillo-femoral by-pass in serious infections of an aortic prosthesis.

Aged↗

PubMed1993

[Treatment of inguinal hernia in local anesthesia: our experience with the Shouldice surgical technique].

The authors present their personal experience in the surgical treatment of 256 cases of patients suffering from inguinal hernia, using the Shouldice technique in local anaesthesia. Minor incidence intra and postoperative complications compared with other types of anaesthesia, the possibility to converse with the patient during the operation and if necessary to invite him to cough in order to exclude the presence of other associated hernias or to assay the robustness and the resistance of the plastic, minor frequency of relapses compared with other operating techniques (1.5% in the Shouldice against 3% of the Bassini), and last but not least the possibility of early discharge from hospital and more swift resumption of work, confirm the full validity of this hernial plastic surgery.

Adult↗

PubMed1993

[The emergency treatment of perforated colonic diverticula].

The authors report their experience of the treatment of 43 cases of perforated colonic diverticula. The operations were: 12 primary resections-anastomoses; 7 resections-anastomoses with protective colostomy; 2 operations of suture and drainage; 22 Hartmann's resections. The authors believe that Hartmann's resection is the operation of first choice in cases of diffuse or stercoraceous peritonitis. This operation another the removal of the sick part of intestines without exposing the patient to the possible complications of an operation "at risk", and allows a late recanalization destitute of risk: in our experience 13 cases of 22 (59%).

Adult↗

PubMed1993

[The "emergency" treatment of celiac trunk obliteration diagnosed during duodenocephalopancreatectomy. A case report].

The authors report about a case of celiac axis obliteration, noticed during an operation of pancreaticoduodenectomy for pancreatic formation. The arterial flux of sovramesocolic district took place completely through the gastroduodenal artery. To complete the operation the authors were obliged to stop the circulation of the pancreaticoduodenal artery and to rivascular the common hepatic through bypass with aorta. The authors confirm the importance of arteriography for the study of expansive lesions of the pancreas, liable to surgical treatment as well to avoid treating urgently similar cases or due to anatomic variants.

Aged↗

PubMed1993

Thymus epithelium induces tissue-specific tolerance.

Most current models of T cell development include a positive selection step in the thymus that occurs when T cells interact with thymic epithelium and a negative selection step after encounters with bone marrow-derived cells. We show here that developing T cells are tolerized when they recognize antigens expressed by thymic epithelium, that the tolerance is tissue specific, and that it can occur by deletion of the reactive T cells.

Animals↗

PubMed1991

Structural requirements for the action of parathyroid hormone-related protein (PTHrP) on bone resorption by isolated osteoclasts.

Parathyroid hormone-related protein (PTHrP) plays a major role in the syndrome of humoral hypercalcemia of malignancy (HHM) by its actions on bone and kidney. In this study an isolated osteoclast bone resorption assay was used to investigate the actions of this peptide and the structure-activity relationships for its resorption effect. As with PTH, neither synthetic nor recombinant PTHrP preparations stimulated resorption within highly purified osteoclast populations. Resorption was stimulated only in the presence of contaminating osteoblasts or in cocultures with the osteoblast-like cell line UMR-106. In the presence of osteoblasts PTHrP-(1-34) and PTHrP-(1-84) stimulated bone resorption in a dose-dependent manner with a potency comparable to that of PTH-(1-34) on a molar basis. The biologic activity of the PTHrP was shown to reside in the first 34 amino acids, and within that region the structural requirements for promotion of osteoclastic resorption resembled closely those for promotion of cyclic AMP formation in osteoblast-like cells. Using emulsion autoradiography with iodinated PTHrP-(1-34) and PTHrP-(1-84) on mixed bone cell preparations from neonatal rats, specific binding was demonstrated only to osteoblasts, not to osteoclasts. These results clearly demonstrate that PTHrP is a potent stimulator of bone resorption and that these effects are, like those of PTH, mediated by initial actions upon cells of the osteoblast lineage.

Animals↗

PubMed1981