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A synergistic increase in the cytotoxic effects of recombinant human tumor necrosis factor (rH-TNF) and hyperthermia was demonstrated both in vitro and in vivo. The cytotoxicity of rH-TNF against L-M cells in incubation for 12 h at 38.5 and 40 degrees C based on the concentration necessary for 50% cytotoxicity was, respectively, 125 and more than 500 times as high as in similar incubation at 37 degrees C. As observed 18 days after implantation of Meth-A fibrosarcoma cells in mice, single i.v. administration of rH-TNF at 1000 units/mouse resulted in complete cures in five mice when performed in combination with hyperthermia (40 degrees C), whereas rH-TNF alone in the same dose resulted in 27.1% inhibition of tumor growth and hyperthermia alone had no appreciable effect on tumor growth. The i.v. administration of rH-TNF three times at 100 or 300 units/mouse together with hyperthermia (40 degrees C) resulted in 41.2 and 89.0% tumor growth inhibition, respectively; similar administration without hyperthermia appeared to have little or no appreciable effect on tumor growth. The results suggest that combination therapy including rH-TNF and hyperthermia may be of value in the treatment of malignancy in human patients.

A circadian rhythm of the susceptibility to thiamylal was evaluated in 30 patients. They were divided into two groups; 15 patients were induced around 9 AM (Morning-group) and the rest were in the early afternoon (Afternoon-group). The induction was performed by intravenous administration of thiamylal sodium. Parameters measured were the time and doses of thiamylal sodium to obtain the loss of consciousness and the loss of eyelash reflex. The results were as follows; the doses of thiamylal sodium to obtain the loss of consciousness were 3.5 +/- 0.6 mg.kg-1 (mean +/- SD) in Morning-group, and 4.1 +/- 0.4 mg.kg-1 in Afternoon-group, respectively. Thus, larger doses of thiamylal were necessary to obtain the loss of consciousness in Afternoon-group than in Morning-group (P less than 0.01). The doses of thiamylal sodium to obtain the loss of eyelash reflex were 4.4 +/- 0.8 mg.kg-1 in Morning-group and 5.0 +/- 0.6 mg.kg-1 in Afternoon-group, respectively. Also, larger doses of thiamylal were necessary to obtain the loss of eyelash reflex in Afternoon-group than in Morning-group (P less than 0.05). This study suggests that a circadian rhythm of the susceptibility to thiamylal exists in humans.

The sequential changes in serum thyroglobulin (Tg), thyroxine (T4), free thyroxine (FT4), triiodothyronine (T3) and thyrotropin (TSH) were evaluated in ten patients on whom partial thyroidectomy for nontoxic nodular goiter had been performed. These changes were compared with those in ten patients who underwent upper abdominal surgery (cholecystectomy) under similar anesthesia, and whose calorie and fluid intake was similar until at least 48 hours after surgery. In agreement with previous reports, marked elevations in serum Tg that reached peak concentration (660 to 1350 ng/mL) at one or two hours after the thyroid incision (mean +/- SD; 787 +/- 304.0 ng/mL and 839 +/- 345.7 ng/mL, respectively) were observed. On the other hand, the significant but minimal increases in serum T4 and FT4 were observed at 24 hours (P less than .001 and P less than .001, respectively), 48 hours (P less than .01 and P less than .001, respectively), and 72 hours (P less than .01 and P less than .01, respectively) after the thyroid incision compared with the level just prior to the thyroid incision. Similarly, serum T3 also increased significantly at 6 to 168 hours after the thyroid incision (P less than .01, P less than .05, P less than .05, P less than .05, and P less than .05, respectively). These increases in serum T4, FT4 and T3 were not observed in the cholecystectomy patients. The mean serum TSH levels at 24 to 72 hours after thyroid incision and those at 6 to 48 hours after the abdominal incision were significantly decreased compared with those before thyroid and abdominal incision, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunological cross-reactivity of L-gulonolactone oxidase of different species (rat, chicken, and bullfrog) was tested by the Ouchterlony technique. Antiserum directed against the enzyme from chicken kidney reacted with rat liver enzyme as well as with bullfrog kidney enzyme. This finding suggests that there is, at least partly, sequence homology among the enzyme from species belonging to the three classes, Mammalian, Aves, and Amphibia.

Several aspects of the activity and effects of tumor necrosis factor (TNF) were investigated to gain further insight into its cytotoxic mechanism. The relation between number of TNF receptors and TNF susceptibility of both tumor cells and normal cells was studied, utilizing a specific binding assay. Among the tumor cells, a fairly close correlation (r = 0.855) was observed between receptor number and sensitivity to TNF. No cytotoxic effect by TNF was observed on any of the normal cells tested, even though TNF receptors were shown to be present, and cell proliferation was apparently stimulated by TNF in some cases. TNF internalization and intracellular distribution were studied by pulse-labelling and Percoll density gradient centrifugation. In L-M (murine tumorigenic fibroblasts, highly sensitive to TNF cytotoxicity) cells and HEL (human embryonic lung cells, non-sensitive to TNF cytotoxicity) cells, receptor-bound 125I-labelled recombinant human TNF was rapidly internalized and delivered to lysosomes within 15-30 min, and this was followed by degradation and release into the culture medium. The presence of either a cytoskeletal disrupting agent or a lysosomotropic agent was observed to inhibit the cytotoxic effect of TNF, thus also indicating that TNF internalization, followed by delivery to lysosomes, is essential in the cytolytic mechanism of TNF. As observed by [3H]uridine incorporation, TNF did not affect RNA synthesis in L-R cells (TNF-resistant cell lines derived from L-M cells) and HEL cells, but markedly stimulated (by 3.5 times) RNA synthesis in L-M cells.

A case of an anaphylactic shock following topical application of chlorhexidine preparation is reported. Specific skin-sensitizing antibodies against chlorhexidine were demonstrated in the serum from the patient by a passive transfer test. IgE antibodies against chlorhexidine were also detected by radioallergosorbent technique (RAST). Paper discs conjugated with chlorhexidine-HSA (human serum albumin) significantly bound the IgE antibodies. Furthermore, all of the sera from seven other patients with shock reactions following the topical application of chlorhexidine preparation also showed high RAST counts. Both chlorhexidine gluconate and chlorguanide which represents approximately half a molecule of chlorhexidine inhibited the reaction in a dose-dependent fashion. It is suggested that the shock reactions following topical application of chlorhexidine are mediated by IgE antibodies against chlorhexidine and that chlorhexidine and chlorguanide share the same antigenic determinant.

A synergistic increase in the cytotoxic effects of recombinant human tumor necrosis factor (rH-TNF) and anti-cancer drugs was demonstrated in vitro. The cytotoxicity of rH-TNF against L-M cells in combination with Mitomycin C (MMC), Adriamycin (ADM), Cytosine arabinoside (Ara-C), Actinomycin D (ACD), Daunomycin (DM), Cisplatin (CDDP), Vincristine (VCR), and 5-Fluorouracil (5FU), based on the concentration necessary for 50% inhibition of cell growth (IC50), was 4 to 347 times as high as that of rH-TNF alone. The results suggest that combination therapy including rH-TNF and anti-cancer drugs may be of value in the treatment of malignancy in human patients.

Exposure of U-937 cells to 12-O-tetradecanoylphorbol-13-acetate (TPA) resulted in specific alterations in thymidine metabolism. Within 24 h after treatment with 1.62 x 10(-9) M TPA, the reciprocal alteration in the activities of opposing enzymes of thymidine metabolism observed during normal cell culture growth was reversed. In TPA-treated cells, the activities of anabolic enzymes thymidine kinase (EC 2.7.1.75)and thymidylate synthase (EC 2.1.1.45) declined with time linearly to 20 and 16% of those of untreated cells by 72 h. Incorporation of [3H]thymidine and [3H]deoxyuridine into acid-insoluble fractions also decreased in parallel with the decline in enzyme activities. In contrast, the activities of catabolic enzymes thymidine phosphorylase (EC 2.4.2.4) and dihydrothymine dehydrogenase (EC 1.3.1.2) increased. The rise in thymidine phosphorylase activity peaked at 48 h with 406% elevation over the control. The activity of dihydrothymine dehydrogenase was not altered for the first 24 h, but it increased up to 338% by 96 h. Immunotitration of dihydrothymine dehydrogenase with monoclonal antibody against this enzyme showed that the rise in activity in the differentiated cells was due to the increase in the amount of enzyme protein. No significant difference was observed in the Km values for the substrate of each enzyme between untreated and TPA-treated cells. These metabolic alterations during induced differentiation were in line with the changes in cell morphology and accompanied by an accumulation of the cells in G1 at the expense of S phase. These observations indicate that induced differentiation of U-937 cells results in a reversal of the enzymic phenotype of thymidine metabolism and suggest that emergence of thymidine metabolic imbalance may serve as an early marker of differentiation of these cells.

Phase specificity in the TNF cytotoxic effect and the number of TNF binding receptors was investigated using L-M cells incubated synchronously from the S phase. TNF cytotoxicity was observed to occur at various levels during the cell cycle, with peak effect in the G2-M phase. Analysis with 125I-labeled TNF to determine the number of receptors binding TNF in the various cell phases shewed a phase specificity with the maximum number occurring in the G2-M phase, similar to the peak in cytotoxicity. The results suggest the existence of a cell cycle specificity in the cytotoxicity of TNF which is apparently related to changes in the number of receptors capable of binding TNF.

Effects of human recombinant TNF on the tumor blood vessels and on the thrombus formation were investigated in relation to its mode of antitumor action against Meth-A sarcoma transplanted in BALB/c mice. The extent of the blood vessel lesion was evaluated by using transparent chamber placed in the mouse skin. Bleeding, hyperemia and congestion were observed at 1-2h, 4-6h and 24h after TNF (1 X 10(4)U/mouse) administration, respectively. In contrast, no histological changes in the normal blood vessels were observed microscopically following TNF injection. Thrombus formation was evoked in the tumor vessels 4h after TNF injection. However, when thrombus formation was prevented by heparin, no difference was observed among antitumor action of TNF against Meth-A fibrosarcoma necrotic response and the rate of complete cure. These results suggest that the direct effects of TNF causing lesions in the tumor blood vessels plays an important role in its antitumor action.

The effect of gold salts on airway responsiveness was examined because gold salts appear to be effective in relieving asthmatic symptoms. Seventeen guinea pigs were administered an intramuscular injection of 1 mg of gold sodium thiomalate once a week, and 10 control animals were administered an injection of saline. Three months after the start of the injections, guinea pigs administered gold salt demonstrated significantly decreased airway responsiveness to histamine assessed by respiratory flow patterns and resistance. Some guinea pigs in each group were sacrificed 3 mo after the start of injections, and cyclic nucleotides were measured in the trachea, lung homogenates, and the plasma. No difference was found in the level of adenosine cyclic 3', 5'-monophosphate or guanosine cyclic 3',5' -monophosphate in gold salt-treated animals and control animals. The way in which gold salt alleviates the symptoms of bronchial asthma is discussed on the basis of the results.

A 73-year-old female was diagnosed as having gastric cancer (undifferentiated adenocarcinoma), and received gastrojejunal anastomosis as an initial treatment. One year after the operation, she was readmitted to our hospital with the complaint of fullness in her stomach. Physical examination revealed a palpable mass in the epigastric region and ascites. An attempt to induce endogenous TNF was made using OK-432. Four doses of OK-432 (10 KE) were administered intraperitoneally every other day. Seven days after the last administration of OK-432 (10 KE), OK-432 (50 KE) was given at the same site to induce TNF. At 1.5h after the injection of OK-432 (50 KE), 20.8 U/ml and 8.1 U/ml of TNF activity could be detected respectively in the serum and ascites. This is the first report describing the induction of TNF in a cancer patient.

We studied the antitumor synergy of human recombinant tumor necrosis factor (TNF) in combination with recombinant interferon-r (IFN-r) both in vitro and in vivo. Synergistic cytotoxic effects were observed in all three of the human tumor cells lines examined. Binding assays of KB human nasopharynx carcinoma cell surface receptors for TNF revealed that IFN-r increased the number of receptors and suggest that this increase may play a key role in the synergism. Furthermore, a remarkable antitumor effect by TNF in combination with IFN-r was observed in nude mice implanted with KB cells. The results thus suggest that TNF and IFN-r in combination may provide the basis for a useful antitumor therapeutic regimen.

Synthetic rat atrial natriuretic factor (ANF) was found to attenuate, in a dose-dependent manner, basal and corticotropin-releasing factor-induced secretion of proopiomelanocortin-derived peptides from cultured anterior and intermediate lobe cells of rat pituitary. ANF was also found to suppress basal and growth hormone-releasing factor-stimulated secretion of growth hormone from anterior lobe cells of rat pituitary. These results, together with reports of the existence of ANF-positive neurons in the hypothalamus and ANF-positive fibers in the median eminence, suggest that hypothalamic ANF is probably involved in the regulation of pituitary hormone secretion, especially that of proopiomelanocortin-derived peptides and growth hormone.