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A 20-yr-old woman with no history of pulmonary disease presented with acute dyspnea and fever. After various investigations and treatments the symptoms persisted and a lung biopsy was performed. Pathologic analysis disclosed the presence of silicotic crystals within lung tissue and mediastinal lymph nodes. The patient admitted having repeatedly inhaled a domestic scouring powder rich in silica during the preceding 6 months. This is the first report of acute pulmonary silicosis developing after exposure to a common household product.

Gangliosides are glycosphingolipids which contain neuraminic acid. Although they are present in the plasma membranes of all cells, gangliosides are expressed differently, both quantitatively and qualitatively, in certain types of cancer. Modifications in ganglioside composition may account for some of the abnormal interactions between these tumor cells and their environment. Furthermore, some of the gangliosides are shed by tumor cells and may modify host immunity, thus contributing to the development of tumors. In cases of melanoma and neuroblastoma, the modifications in ganglioside expression are such that gangliosides may be used both as tumor markers and as targets for immunotherapy.

Distal metastases are classically situated below the knee or elbow. However, metastases of the extremities: wrist and hand, or ankle and foot, have etiological and histological characteristics. We report one case of bone metastasis and one case of soft tissue metastasis. The distal bone metastases are often solitary. Bronchial cancers represent the most frequent cause of distal metastases (20% of all cases). They are responsible for 50% of distal metastases of the upper limb and more often occurs as a squamous cancer. Their localization may sometimes reveal a bronchial cancer, and so allow curative surgery. The metastases of soft tissue are exceptional. In the literature, only 2 cases of soft tissue metastasis of bronchopulmonary cancer are described. Clinically, it is a painful swelling preserving the under lying bone. The prognosis is always one of bronchial metastasis cancer with an average survival of 3-6 months.

A purification procedure for a protein related to lactoperoxidase devoid of the heme prosthetic group under conditions also yielding enzymatically active lactoperoxidase is described. These two forms were separated from bovine milk according to their respective behaviors on cation exchange. Lactoperoxidase and non-heme lactoperoxidase had the same apparent molecular weight in the denatured (sodium dodecyl sulfate-polyacrylamide gel electrophoresis) and native form (velocity sedimentation on sucrose gradient) about 85,000; but unlike lactoperoxidase, non-heme lactoperoxidase was devoid of light absorption properties in the Soret region and of enzyme activity. Lactoperoxidase and non-heme lactoperoxidase contained a similar amount of carbohydrate and gave very similar peptide maps after limited proteolysis by subtilisin or trypsin. The two forms appeared to be immunologically related since they gave a single line in immunodiffusion using anti-lactoperoxidase antibodies and since 125I-labeled non-heme lactoperoxidase and 125I-labeled lactoperoxidase reacted with anti-lactoperoxidase antibodies in radioimmunoassay. Lactoperoxidase and nonheme lactoperoxidase were compared in their ability to interact with diiodotyrosine and tubulin (Rousset, B., and Wolff, J. (1980) J. Biol. Chem. 255, 2514-2523). 125I-labeled diiodotyrosine bound specifically to lactoperoxidase. No detectable binding has been observed with nonheme lactoperoxidase. In contrast, lactoperoxidase and non-heme lactoperoxidase coupled to an insoluble matrix were able to bind rat brain tubulin, indicating that both forms of lactoperoxidase can be used for an affinity chromatography purification procedure of brain tubulin. Non-heme lactoperoxidase was found in milk from several origins, cow, goat, sheep, and human. In bovine milk, lactoperoxidase and non-heme lactoperoxidase were found in comparable amounts.

Monoclonal antibodies, produced in vitro from hybridoma supernatants, may be administered to cancer patients either directly or after coupling to an anticancer agent (immunoconjugates). Monoclonal antibodies concentrate in tumor site, where they initiate an anti-tumor effect, either by activation of the patient's immune system or by the cytotoxic agent which is present at high concentration within the tumor, while systemic concentrations of this agent remain low. Monoclonal antibodies which are radiolabelled also allow the immunoscintigraphic study of the immunoconjugates' diffusion within the body. Given certain precautions of administration, the clinical and biological tolerance of this type of treatment is satisfactory, most of the side effects correspond to an allergic response to the murine antibodies used. Clinical studies performed in patients with leukemias have demonstrated a significant antitumor effect although this effect is transitory. Studies performed on small series of patients with solid tumors (gastrointestinal neoplasms, melanoma, leptomeningeal localizations, ovarian peritoneal carcinosis) have shown a few cases of major responses and/or complete remissions having lasted up to periods of many months. These studies as well as the perspectives for the development of this type of therapy are presented and discussed.

The characteristics of the dose response of insulin on the glucose turnover rate and erythrocyte insulin binding parameters were determined in five normal men before and during experimentally induced hyperthyroidism [L-T4 (2 micrograms kg-1 day-1) for 4 weeks with additional L-T3 (1 microgram kg-1 day-1) for the following 3 weeks]. Hyperthyroidism was characterized by significant rises in T3 from 1.92 +/- 0.17 (+/- SEM) to 3.66 +/- 0.17 nmol/liter (P less than 0.01) and resting metabolic rate from 39 +/- 0.7 to 48 +/- 1 watt/m2 (P less than 0.001). While the subjects received a diet adapted to the metabolic rate, blood glucose rose from 3.8 +/- 0.07 to 4.46 +/- 0.11 mmol/liter (P less than 0.05) without a significant change in plasma insulin. During the insulin dose-response study, glucose infusion rates were unaltered by hyperthyroidism, and neither the maximum effect nor the sensitivity to insulin was altered. Glucose turnover rate, measured using [6,6-2H2]glucose as tracer, was determined in the basal state and during the 0.4 mU kg-1 min-1 insulin infusion. In the basal state, it was significantly increased by hyperthyroidism (control, 2.3 +/- 0.1; hyperthyroidism, 3.7 +/- 0.1 mg kg-1 min-1). During the insulin infusion, hepatic glucose production was totally suppressed before T4 and T3 treatment, but was 0.96 +/- 0.39 mg kg-1 min-1 during T4 and T3 treatment. A marked decrease in the insulin binding affinity to erythrocytes was found without a change in the insulin receptor number. In conclusion, glucose metabolism in experimental hyperthyroidism is characterized by 1) increases in basal glucose production and utilization; 2) antagonism between the effect of insulin and hyperthyroidism at the hepatic level; and 3) lack of peripheral insulin resistance in spite of marked alteration in erythrocyte insulin binding affinity.

HTLV-I has recently been shown to be a direct activator of resting human peripheral T cells. In order to determine the susceptibility of T-cell precursors to HTLV-I mitogenic activity we have exposed human thymic T cells to uv-inactivated HTLV-I. Unlike mature T cells, thymocytes were not directly susceptible to HTLV-I-induced activation although agglutination of cells did occur after exposure to HTLV-I alone. However, in the presence of another stimulus, phyto-hemagglutinin or anti-CD3 monoclonal antibodies and accessory cells, thymocytes proliferated when exposed to HTLV-I. Concanavalin A did not induce HTLV-I comitogenic activity. HTLV-I-induced thymocyte proliferation was enhanced by autologous or heterologous accessory cells. This proliferation was shown to be mediated by the interleukin-2/interleukin-2 receptor pathway. Simultaneous stimulation by HTLV-I and nonmitogenic doses of phytohemagglutinin were required both for the production of interleukin-2 and for the expression of the interleukin-2 receptor. These data demonstrated functional differences between peripheral T cells and thymocytes.

A case of left brachial plexus compression by an iatrogenic arteriovenous fistula was treated by detachable balloon technique with immediate relief of pain. Good results on paresia were obtained in a few weeks.

Lipoma arborescens is a rare intra-articular tumor usually found in the knee joint. The reported lesion involved the inferomedial recess of the right hip synovium, in a 29-year-old male. The clinical findings were nonspecific. Both arthrography and computerized tomography (CT) of the hip disclosed the tumor which, on CT examination, showed an inhomogeneous low density, due to its fat content. The final diagnosis was given by histological examination of the resected mass. No recurrence was observed after one year. The long-term prognosis probably depends more on the underlying disorder of the joint than on the lipoma itself.

Monoclonal antibodies directed against antigens borne by tumors have already been the object of clinical trials in patients with leukemia or solid tumors. These antibodies, generally obtained from murine hybridomask, are used alone or as immunoconjugates, i.e. coupled to a non-specific antimitotic agent. Under the proper conditions they may be administered with a satisfactory clinical and biological tolerance. The antimitotic action of these antibodies, which is specifically directed against neoplastic cells, has been demonstrated in vitro and in animal models and is found inconstantly in leukemias. Studies have been performed in patients bearing solid tumors, with large initial tumoral mass, showing partial regression in a few cases. A number of parameters, including modalities of administration, types of immunoconjugates and mechanisms of action in vivo, must be explored to increase the antineoplastic potential of monoclonal antibodies.