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Biomedical subjects

G Peri

Publications and source records attributed to G Peri.

At least 73 records · Page 4Linked to original sources
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↗
PubMed1986

Evaluation of the interaction of mononuclear phagocytes with ovarian carcinoma cells in a colony assay.

The effect of human peripheral blood monocytes on the SW626 ovarian carcinoma line was investigated in a colony assay in agar, Percoll-enriched monocytes inhibited colony formation by SW626 carcinoma cells at effector-to-target cell (E:T) ratios as low as 0.3:1. In contrast the same effectors had little cytolytic effect in a 48 h thymidine-release assay at E:T ratios as high as 40:1. Monocyte-depleted nonadherent cells had little inhibitory capacity on SW626 colony formation, whereas unseparated mononuclear cells were intermediate between Percoll-enriched monocytes and lymphoid cells. Sorting of cells positive for the monoclonal antibody marker MO2 confirmed the monocytic nature of cells which inhibited colony formation. Ovarian carcinoma cells freshly isolated from 9 patients were heterogenous in their susceptibility to colony inhibition by mononuclear phagocytes. Cells from 4 patients were not inhibited by effector cells and in one subject promotion of colony formation by mononuclear phagocytes was observed. With 4 cell preparations inhibition of colony formation was found as with the SW626 line. Colony assays may provide a useful methodological approach, particularly when effector cells mediate low levels of killing, of doubtful biological significance, in conventional isotope release assays, or when growth promotion is to be evaluated.

Cell Line↗
PubMed1986

[Intraorbital abscess of dental origin in a child].

A two years old girl developed orbital infection secondary to dental trauma. Computed tomographic scanning of the orbit shows subperiosteal abcess in the medial orbital wall and proptosis of left globe. Teeth removal, appropriate antibiotics and surgical drainage are essential for preservation of vision.

Abscess↗
PubMed1986

[Cutaneous parotid fistula of calculous origin].

A case of cutaneous salivary fistula is presented. A 42-year-old man had a recurrent inflammatory parotid disease which disappeared with the expulsion of the calculus. The authors note the rarity of this evolution in the literature and suggest a protocol of treatment.

Adult↗
PubMed1986

Ia antigen expression and IL-1 activity in murine tumour-associated macrophages.

Tumour-associated macrophages (TAM) isolated from five murine sarcomas had a relatively high frequency of I-A+ cells, with mean values of 27% (mFS6), 52% (MN/MCA1), 68% (N3), 62% (N4) and 98% (J3) for TAM compared to 12% for resident peritoneal macrophages. Expression of I-E in TAM was also high (29%) in the only sarcoma (N4) examined in this respect. Expression of I-A by TAM declined in culture but exposure to lymphokine supernatants maintained and increased the frequency of I-A+ cells in TAM. Transplantation of tumours into nude mice caused a marked decrease in the percentage of I-A+ TAM in the case of the N4 sarcoma (8% compared to 48%), whereas for the MN/MCA1 sarcoma the diminution was only marginal (from 53 to 41%), TAM from murine sarcomas did not constitutively release appreciable levels of interleukin-1 (IL-1) activity. Upon stimulation with bacterial lipopolysaccharides or silica, TAM showed a limited capacity to produce and release IL-1 activity compared to peritoneal macrophages. Thus the expression of I-A antigens and the IL-1-producing capacity are uncoupled in TAM from murine sarcomas. These properties of TAM could play an important role in the generation of anti-tumour immunity and/or of suppressive T-cell circuits.

Animals↗
PubMed1985

Effects of inactivated streptococci (OK-432) on macrophage functions in mice.

The effects of inactivated streptococci (OK-432) on murine macrophage functions were investigated. In vivo treatment of peritoneal macrophages with OK-432 augmented the direct cytotoxic activity against TU5 tumor cells in a 48 h tritiated thymidine release assay. OK-432 also stimulated the rapid (6 h, 51Cr release) macrophage-mediated killing of Actinomycin D-sensitized WEHI 164 sarcoma cells. Moreover, the expression of la antigens on peritoneal macrophages was found to be greatly enhanced after in vivo treatment with OK-432. The immunomodulatory effects of OK-432 on macrophages functions may contribute to the antitumor activity of inactivated streptococci.

Animals↗
PubMed1985

Natural killer cells in intravenous drug abusers with lymphadenopathy syndrome.

We have investigated 25 intravenous drug abusers with the clinical and laboratory features of lymphadenopathy syndrome (LAS) and 10 AIDS patients for the expression of NK activity. LAS and AIDS patients had low NK cytotoxicity compared to normal donors. The defective NK cytotoxicity was analysed in the eight LAS subjects with most marked depression. NK effectors were identified by morphology (large granular lymphocytes, LGL) and monoclonal antibody-defined surface markers (B73.1, N901, HNK1). LAS patients had normal percentages of LGL and B73.1+ and N901+ cells. with the exception of two subjects with very low frequency of B73.1+ and N901+ cells. The percentage of HNK1+ cells was increased in LAS, probably because of the reactivity of this reagent with a subset of conventional OKT8+ cells, relatively augmented in LAS subjects. Depletion of monocytes did not enhance NK activity consistently. LAS patients had a normal frequency of cells capable of binding K562. In-vitro exposure to interferon beta (natural) or gamma (recombinant) augmented the defective NK activity of LAS subjects. Thus, patients with LAS have defective NK activity that cannot be accounted for by a low frequency of the relevant effector cells or by monocytic suppressors. These observations suggest a functional defect of NK cells at one or more of the post-binding steps required for the completion of killing.

Acquired Immunodeficiency Syndrome↗
PubMed1985

Natural anti-bacterial activity against Salmonella typhi by human T4+ lymphocytes armed with IgA antibodies.

Peripheral blood mononuclear cells from normal volunteers possess natural anti-bacterial (NA) activity against S. typhi that can be measured in a 2-hr in vitro assay. Employing fractionation on nylon wool columns, Percoll gradients, plastic adherence, and E rosetting, the effector cell of NA activity appeared to be a lymphocyte of the T lineage rather than a macrophage, a B lymphocyte, or a large granular cell. Moreover, complement-dependent killing with monoclonal antibodies such as OKM1, OKB7, OKT8, 5.9 and the anti-natural killer cells AB8.28 did not reduce NA activity. On the contrary, this was completely inhibited when OKT3, OKT11, or OKT4 antibodies and complement were used to pretreat the effector lymphocytes. Indeed, T4+ cells sorted with a FACS displayed an extremely high NA activity against S. typhi. By pretreatment of peripheral lymphocytes with F(ab')2 fragments against human IgA, the NA activity was blocked. It is therefore suggested that NA activity by human cells might be a mechanism of defense against infections, acting as antibody-dependent cellular cytotoxicity expressed by T4+ lymphocytes coated with preexisting anti-Salmonella IgA antibodies.

Antibodies, Bacterial↗
PubMed1984

[Ultrastructural observations on the presence of stereocilia in myoblasts of Scyllium stellare].

Many Authors described primary 9+0 cilia in different tissue of different animal species. In relation to the study on the ultrastructural architecture of the embryonic heart of a elasmobranch "Scyllium stellare", we saw some primary 9+0 cilia in very undifferentiated heart tissue. The hearts dissected from the Scyllium stellare embryo at 6 months of gestation, were processed for the observations at the transmission electron microscope. The cilia are found in deep invagination of the plasma membrane, near the Golgi complex and in the perinuclear region. Various functions have been postulated for the primary 9+0 cilia.

Animals↗
PubMed1984

Monoclonal antibody-defined surface markers of effector cells involved in human monocyte cytotoxicity.

Human adherent peripheral blood mononuclear cells were cytotoxic in vitro against the murine TU5 line in a 48-hr [3H]thymidine-release assay. Monocyte-enriched adherent cell preparations contain a small and variable (usually less than 5%) contamination with large granular lymphocytes as assessed by morphology and staining with monoclonal antibody markers B73.1 and HNK1. To assess whether killing was in fact mediated by monocytes, mononuclear cells or monocyte-enriched preparations were separated using monoclonal antibodies directed against mononuclear phagocytes (Mo2, UCHM1, B44.1) or natural killer (NK) cells (B73.1 and HNK1), and a fluorescence-activated cell sorter. Cells positive for monocyte markers were highly cytotoxic against TU5, whereas negative cells were not. B73.1+ or HNK1+ cells had little or no activity. Cytotoxicity of cells positive for monocyte markers (Mo2, UCHM1, B44.1) was augmented by in vitro exposure to lymphokines or less frequently to interferon (IFN). However, cells negative for these monocytes markers were also stimulated to kill TU5 by lymphokine or IFN to an extent similar or greater than that of positive ones. IFN or lymphokines induced killing of TU5 by monocyte-depleted, B73.1-positive, lymphoid cells. These observations demonstrate that human monocytes do kill tumor cells, either in the absence of deliberate stimulation or after exposure to agents such as lymphokines. However, the possible contribution to "monocyte" cytotoxicity of minor NK cell contaminants must be taken into account particularly when agents such as IFN and lymphokines are applied, even when a relatively NK-cell-resistant target such as TU5 is used.

Antibodies, Monoclonal↗
PubMed1984

[Surgical indications in craniofacial injuries].

Precise definition of indications for surgery in patients with craniofacial injury is impossible, and individual assessment of each case by the surgeon can be a source of errors. These may be due to excess or omission when confronted with bone lesions which fail to supply information on the state of the dura mater, and with rhinorrhea with lack of sufficient criteria to assess the condition of the dura mater and its capacity for healing. Indications should therefore be modulated as a function of the different anatomoclinical types involving different risks. On the other hand, one should not search for perfection since other factors are involved when operating under emergency conditions, and one must not err by presumption, knowing that no reconstruction is perfect.

Craniocerebral Trauma↗
PubMed1984

Rapid killing of actinomycin D-treated tumor cells by human mononuclear cells. I. Effectors belong to the monocyte-macrophage lineage.

Preincubation of tumor cells with actinomycin D (Act D) rendered various murine and human lines susceptible to killing by unstimulated human peripheral blood mononuclear cells (PBM) in a 6-hr 51Cr-release assay. The murine WEHI 164 sarcoma was selected for analysis of drug-dependent cellular cytotoxicity (DDCC) because high levels of killing were detected with this tumor, and it was considerably resistant to natural killer (NK) cell activity. Optimal conditions for induction of susceptibility to lysis included a 3-hr preincubation with 1 microgram/ml Act D. Effector cells of cytotoxicity against Act D-treated WEHI 164 cells were plastic adherent (greater than 85% monocytes). Cells nonadherent to plastic and nylon wool (less than or equal to 1% monocytes) had no appreciable DDCC activity. In contrast NK activity against K562 cells was mediated by nonadherent cells. When PBM were fractionated on a one step discontinuous gradient of Percoll designed to enrich for monocytes (greater than 90% pure), DDCC activity was found in the monocyte fraction, and the lymphoid cell-enriched fraction had no cytotoxicity against Act D-treated WEHI 164 cells. In contrast, NK activity against K562 was recovered with lymphoid cells, and monocytes had no NK cytotoxicity. Upon fractionation on a six step Percoll gradient designed to enrich for large granular lymphocytes (LGL), the denser lymphocytes (fraction 4-6) and the less dense LGL with NK activity (fraction 2-3) had no cytotoxicity against Act D-treated WEHI 164 sarcoma cells. DDCC activity sedimented in fraction 1 in association with monocytes. PBM were fractionated according to monoclonal antibody-defined surface markers by using a fluorescence-activated cell sorter. Effector cells of DDCC were positive for monocyte markers (Mo2, UCHM1) and were negative for NK cell (B73.1, HNK1), T cell (T11), and B cell (Leu-10) markers. Macrophages obtained by culturing blood monocytes in vitro for 5 to 10 days had DDCC activity. Similarly, peritoneal and bronchoalveolar macrophages had considerable cytotoxicity against Act D-treated target cells, whereas minimal or no NK activity was found at these anatomic sites. Cells of human or murine origin, preincubated with Act D for 3 hr, were heterogeneous in their susceptibility to monocyte killing in a 6-hr 51Cr-release assay. High levels of cytotoxicity were observed with the murine WEHI 164 sarcoma and 3T3 "fibroblast" line and with the human CEM leukemia. Monocytes were weakly (but significantly) cytotoxic against the ALAB breast carcinoma (human) and the 8387 sarcoma (human).(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1983

In vitro and in vivo cytotoxicity of possible uracil metabolites of methylxanthines.

The present study was designed to elucidate the cytotoxic potential of 8 possible substituted uracilic metabolites of methylxanthines. 5-Fluorouracil (5-FU) was used as a reference uracil analogue with cytotoxic activity. Substituted uracil derivatives examined in this study did not affect the proliferative capacity of PHA-stimulated rat lymphocytes, murine L1210 leukaemia and rat chondrocytes. Caffeine had some growth inhibitory activity of extremely high concentrations (greater than 100 micrograms/ml). In vivo administration of 6-amino-5[N-methyl-formylamino]1,3-dimethyluracil (1,3,7-TAU) and 6-amino-5[N-acetylamino]3-methyluracil (7-A3-MAU) caused a transient short-lived reduction of L1210 tumour cell numbers. These observations do not appear to support the hypothesis that substituted uracils are involved in the toxicity of high doses of caffeine in rats.

Animals↗