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G Peri

Publications and source records attributed to G Peri.

At least 37 records · Page 2Linked to original sources
PubMed1991

Involvement of leukocyte (beta 2) integrins (CD18/CD11) in human monocyte tumoricidal activity.

Appropriately activated mononuclear phagocytes mediate contact-dependent tumoricidal activity. Adhesion structures involved in contact-dependent tumor cytotoxicity have not been defined. The present study was aimed at identifying the adhesion structures involved in the tumoricidal activity of activated (IFN-gamma + LPS) human monocytes. Tumor cells of different histological origin were used as targets in a 48-hr cytolysis assay. Anti-CD18 (integrin beta 2 chain) monoclonal antibodies (MAbs) substantially (50-80%) inhibited human monocyte cytotoxicity. When the role of different a-chains was studied, anti-alpha L (CD11a, LFA1), anti-alpha M (CD11b, Mac-1) and anti-alpha X (CD11c, p150,95) caused marginal inhibition, but the effect of the 3 combined was comparable to that of anti-CD18. Anti-CD18 MAb did not affect the release of various cytotoxic molecules (e.g. TNF) by activated human monocytes. Activated monocytes showed augmented binding to target cells and anti-CD18 MAb inhibited the binding of resting and activated monocytes to tumor target cells. While IFN-gamma alone augmented expression of leukocyte integrins and LPS had no effect, the 2 activation signals, combined for optimal stimulation of tumoricidal activity, resulted in no appreciable increase in these leukocyte adhesion molecules, as assessed by flow cytometry. Our results suggest that the augmented CD18-dependent binding of activated monocytes on tumor cells depends mainly upon changes in the adhesive properties of these molecules rather than upon increased numbers on the cell surface. Anti-ICAM-1 MAb significantly reduced monocyte cytotoxicity on tumor cells, which is consistent with a role of the CD11/CD18 adhesion pathway. These results implicate "activated" leukocyte (beta 2) integrins (CD11/CD18) as important adhesion molecules in the contact-dependent tumoricidal activity of human monocytes.

Antibodies, Monoclonal↗
PubMed1991

Molecules and structures involved in the adhesion of natural killer cells to vascular endothelium.

The present study was designed to define molecules and structures involved in the interaction of natural killer (NK) cells with the vascular endothelium in vitro. Resting and interleukin 2 (IL-2)-activated NK cells were studied for their capacity to adhere to resting and IL-1-treated human umbilical vein endothelial cells (EC). In the absence of stimuli, NK cells showed appreciable adhesion to EC, with levels of binding intermediate between polymorphs and monocytes. The binding ability was increased by pretreatment of NK cells with IL-2. Using the appropriate monoclonal antibody, the beta 2 leukocyte integrin CD18/CD11a was identified as the major adhesion pathway of NK cells to unstimulated EC. Activation of EC with IL-1 increased the binding of NK cells. In addition to the CD18-CD11a/intercellular adhesion molecule pathway, the interaction of resting or IL-2-activated NK cells to IL-1-activated EC involved the VLA-4 (alpha 4 beta 1)-vascular cell adhesion molecule 1 receptor/counter-receptor pair. No evidence for appreciable involvement of endothelial-leukocyte adhesion molecule was obtained. Often, NK cells interacted either with the culture substrate or with the EC surface via dot-shaped adhesion structures (podosomes) protruding from the ventral surface and consisting of a core of F-actin surrounded by a ring of vinculin and talin. The identification of molecules and microanatomical structures involved in the interaction of NK cells with EC may provide a better understanding of the regulation of NK cell recruitment from blood, their extravasation, and their migration to tissues.

Antibodies, Monoclonal↗
PubMed1991

The "critical zones" of entrapment of the nerves of the lower limb.

The author has studied, in a group of 40 dissections on cadavers of individuals of different ages, the main "critical zones" of entrapment of some terminal branches of the lumbo-sacral plexus, which include canals (fibrous, osteo-fibrous, fibro-muscular), intervals (intermuscular, fibro-muscular, musculo-ligamentous), rings (fibrous or fibro-muscular) and foramina. They provide the topographical anatomical basis for possible compressive phenomena of the nerves of the lower limb.

Fascia↗
PubMed1991

Parental perceptions of childhood illness.

This article takes parental perception as the starting point of an analysis of the relationship between ill children, their families, and their doctors in the handling of a child's illness. A modified version of Creer, Marion, and Creer's Asthma Problem Behavior Checklist, adapted to suit Italian conditions, was used. The questionnaire was given to a sample of 460 parents of 230 preadolescent children. The sample was divided into two groups: The first sample was comprised of 84 parents of 42 preadolescent children with atopic symptoms (asthma, bronchitis, or hay fever), and the second sample was comprised of 376 parents of 188 preadolescents who had never had either atopic disturbances or any other serious disease. The results showed that both groups of parents felt their children were capable of autonomously managing their disease, and that they see medical facilities as their primary resource. Children were not perceived as being altered by their illness, although their illness undoubtedly affected family relationships; this was particularly true in the case of families with members who experience atopic problems. The factors causing the greatest difficulties were: disagreements over treatment, anxiety caused by the disease, and the sacrifices made by family members as a result of illness.

Adolescent↗
PubMed1990

Cytotoxicity of activated monocytes on endothelial cells.

Unstimulated human monocytes did not express appreciable levels of cytotoxicity on normal human umbilical vein endothelial cells (EC) in a 24-48 hr TdR release assay. On activation with IFN-gamma and LPS, monocytes had appreciable cytotoxicity on EC. Monocyte cytotoxicity on EC was not dependent on the presence of contaminating lymphoid cells. Recombinant TNF, IL-1, and IL-6 as well as monocyte supernatants did not exert a cytotoxic effect on EC. Moreover, anti-TNF, anti-IL-1, and anti-IL-6 antibodies, as well as scavengers of reactive oxygen intermediates, did not affect the cytotoxicity of activated monocytes on EC. Antibodies against the beta-chain (CD18) of leukocyte integrins inhibited the adhesion and cytotoxicity of activated monocytes on EC. Pretreatment of EC with IL-1 augmented the adhesion of monocytes on EC. Normal monocytes were not cytotoxic on IL-1-pretreated EC and IL-1 treatment did not increase the susceptibility of EC to activated monocytes. Thus adhesion is necessary but not sufficient for monocyte killing of EC. Anti-alpha L (LFA-1) antibodies markedly reduced monocyte cytotoxicity on EC, although anti-alpha X (p150) antibodies had only a modest effect. Anti-alpha M (Mac-1/CR3) antibodies were intermediate inhibitors of EC killing by activated monocytes. Thus, alpha L, beta 2 (LFA-1), and, to a lesser extent, alpha M, beta 2 (Mac-1/CR3) and alpha X, beta 2 (p 150, 95) integrins are the main adhesive structures involved in the cytotoxic interaction of activated monocytes with EC. Monocyte-mediated damage of EC could play a role as a mechanism of tissue injury under conditions of local or systemic activation of mononuclear phagocytes.

Antigens, Differentiation↗
PubMed1990

[The submental island skin flap. A surgical protocol. Prospects of use].

The authors report their use of a previously undescribed skin flap situated in the submental region and vascularised by the submental artery derived from the facial artery. It is possible to raise flaps as large as 11 cm X 6 cm with an identical colour to that of the face. The pedicle flap can reach any part of the homolateral oral cavity or the lower 2/3 of the homolateral side of the face (with the exception of the nasal region). The free flap, using a good calibre pedicle (including facial arteries and veins, may be as long as 7 cm and appears to be extremely reliable. It is also possible to use a distal or composite pedicle taking a segment of the internal basilar margin. The donor site scar dissimulated under the mandible is perfectly acceptable.

Arteries↗
PubMed1990

[Ongoing clinical study of oral lichen planus (OLP) treated with retinoids: one used locally, (tretinoin) the other orally (etretinate)].

Twenty patients with oral lichen planus (OLP) were divided into two groups. The first group (8 reticulated OLP, 2 hyperkeratotic OLP) was treated with topical tretinoin. The second group (4 reticulated OLP, 6 eroding OLP) was treated with oral etretinate. All patients were regularly followed in order to observe over a period of five years the evolution of the lesions under treatment, the side-effects and recurrences when the treatment was discontinued.

Adult↗
PubMed1989

[Glossectomies].

Explore the source record for details and available documents.

Adolescent↗
PubMed1988

[The osteocutaneous outer arm flap. A new concept in microsurgical mandibular reconstructions].

The authors present five cases where the OCLAF technique was adapted to reconstruct large mandibular defects. Some significant advantages made us think about the possibility of the OCLAF as an acceptable alternative in that specific case. These are the ease and safety of the dissection, the respect of a bony vascularisation, a very valuable pedicle size, and a remarkable mobility of the skin paddle to the underlying bone. Of course we had to face some minor disadvantages: the microsurgical procedure, the donor site scar, the absence of cancellous bone in the transfer and the weakening of the bone shaft at the donor site. Nevertheless we think the OCLAF is to be considered whenever large mandibular defects have to be reconstructed with vascularized bone.

Adult↗
PubMed1988

[Vagal paraganglioma. Apropos of 2 cases. Review of the literature].

The authors relate the case of two patients of 61 and 64 years old, each one having a high latero-cervical tumor, arching the soft palate, developed from the right vagus nerve and which was a chromaffin paraganglioma. After a recall about the APUD system tumors and the "paraganglioma" concept, they relate their observations at state of the vagal paraganglioma histology, pathology and treatment.

Female↗
PubMed1988

Lymphocytes infiltrating ovarian carcinoma: modulation of functional activity by intraperitoneal treatment with biological response modifiers.

A better understanding of the immunobiology of tumor-associated lymphocytes (TAL) may have considerable bearing on the therapeutic perspective of human neoplasia. We have identified ovarian cancer as a clinical condition privileged for studies on immunity and its in vitro and in vivo modulation. Our previous studies on the mechanisms of natural resistance have shown that TAL from ovarian carcinoma have defective natural killer cell activity when compared to peripheral blood lymphocytes from the same patient. This low natural killer cell activity could be stimulated in vitro by biological response modifiers (e.g. interferons) and these findings led us and others to design clinical trials based on intraperitoneal infusions of these agents. Interleukin-2 was extremely effective at inducing or augmenting cytotoxicity in TAL (lymphokine-activated killer cell activity). TAL-generated lymphokine-activated killer cells were cytotoxic against autologous and allogeneic fresh carcinoma cells. This finding provides a rationale for direct intraperitoneal infusion of this cytokine in ovarian cancer.

Female↗
PubMed1988

[Cholesteatoma of the facial sinuses. Apropos of an ethmoid-orbital cholesteatoma].

A case of cholesteatoma of the ethmoid extending to the orbit is reported. These cholesteatomas of facial sinuses are rarely reported, those documented involving localization in maxillary or frontal, or ethmoido-frontal or ethmoido-maxillary sinuses. Primary perisinusal cholesteatomas of embryonic origin must be distinguished from the rarer secondary iatrogenic or post-traumatic lesions. Histopathology allows distinction between epidermoid cysts and cholesterol type granulomas. Treatment is by surgery using a wide approach.

Aged↗
PubMed1987

Cytotoxic effector function of B lymphoblasts.

EBV-transformed B lymphoblastoid cell lines and clones were cytotoxic in vitro against Actinomycin D-pretreated WEHI 164 sarcoma cells, a system in which mononuclear phagocytes were previously identified as effectors. Similarly, unlike resting B cells, normal B lymphoblasts stimulated for 72 hr with Staphylococcus aureus Cowan I and purified according to the expression of the B cell surface marker B1, demonstrated appreciable cytolytic activity. B lymphoblastoid cells and derived supernatants were cytotoxic for Actinomycin D-pretreated WEHI 164 cells, and killing was inhibited by an anti-lymphotoxin but not an anti-tumor necrosis factor antiserum. Thus, B lymphoblasts have cytotoxic potential, mediated by lymphotoxin or a lymphotoxin-like soluble product.

B-Lymphocytes↗
PubMed1987

Platelets express a membrane protein complex immunologically related to the fibroblast fibronectin receptor and distinct from GPIIb/IIIa.

We have previously identified and characterized a membrane glycoprotein complex (GP150/135) that functions as fibronectin receptor (FN-R) in fibroblast adhesion. Here we report that an immunologically related protein complex is expressed at the surface of human platelets. Antibodies monospecific for the smaller subunit (GP135) of the fibroblast FN-R in fact specifically stained the platelet surface, as determined by FACS analysis, and reacted with a component of molecular weight (mol wt) 138,000 as shown in western blots of platelet membranes. Moreover, the same antibodies precipitated the 138,000 component together with a 160,000 protein, suggesting that the two molecules are associated in a supramolecular complex. A comparative analysis indicated that this protein complex is distinct from the GPIIb/IIIa complex, known to function as a receptor of wide specificity for fibrinogen, fibronectin, and von Willebrand factor. Differential extraction experiments revealed that the platelet 138,000 component is an integral membrane protein.

Antibodies↗
PubMed1987

[Long-term results of glossectomies].

Analysis of results of a series of marginal glossectomies, performed for orthodontic or orthopedic indications over the last 10 years, showed sustained improvement of alveolar process inclination with practically inexistant functional or psychologic sequelae.

Adolescent↗
PubMed1987

[Posttraumatic pseudoaneurysm of the zygomatic area].

A case of post-traumatic false aneurysm of a segment of the zygomato-malar artery is used as a basis for a discussion of this fairly rare complication of facial injuries and the complementarity of angiographic examinations and surgical exploration findings.

Adult↗