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C T Bever

Publications and source records attributed to C T Bever.

50 records · Page 3Linked to original sources

Cortisol induction by poly ICLC: implications for clinical trials of interferon.

Because interferon injections have recently been reported to induce cortisol in cancer patients, we retrospectively reviewed cortisol levels obtained during a preliminary trial of the interferon inducer polyriboinosinic polyribocytidylic acid in poly-L-lysine and carboxymethylcellulose (poly ICLC) in multiple sclerosis patients to determine if significant cortisol induction occurred. Analysis of data from 51 poly ICLC infusions in 6 men and 4 women showed elevated cortisol levels 4 to 16 hours after infusion, with hematological changes consistent with steroid effect. The highest cortisol levels observed were in 2 patients who improved during the treatment period, but there was no clear relationship between cortisol levels and clinical outcome in the group as a whole.

Adult↗

The kinetics of interferon induction by poly ICLC in humans.

A preliminary trial of the interferon (IFN) inducer polyriboinosinic acid-polyribocytidylic acid in poly-L-lysine and carboxymethylcellulose (poly ICLC) was conducted in patients with chronic progressive multiple sclerosis (MS). Because IFN induction in men is greater than in women, the kinetics of IFN induction were studied. As no significant differences were found in the serum half-life of IFN, sex-linked differences in IFN clearance or degradation are not likely to be responsible for the differences noted. Because fever was the major limiting side effect in MS patient, the relationship of fever to IFN levels was assessed. Changes in temperature were not related to changes in IFN levels, suggesting that fever might be blocked without reducing IFN levels.

Carboxymethylcellulose Sodium↗

Preliminary trial of poly ICLC in chronic progressive multiple sclerosis.

Eighteen patients with chronic progressive multiple sclerosis (MS) were treated in an open preliminary trial of the interferon inducer and immune modulator, poly ICLC. All patients produced substantial interferon levels and experienced acute side effects, including fever and transient worsening of neurologic symptoms. Of nine patients with rapid neurologic deterioration at the time of entry into the study, only three had disease progression during treatment. We conclude that poly ICLC can be administered safely to MS patients, and that a controlled trial will be necessary to determine efficacy.

Adult↗

A comparison of interferon responses to poly ICLC in males and females.

Interferon (IFN) responses to polyriboinosinic acid polyribocytidylic acid in poly-L-lysine and carboxymethylcellulose (poly ICLC) have been studied in detail in 6 men and 3 women as part of a preliminary trial in patients with multiple sclerosis (MS). Patients received intravenous (i.v.) doses of 100 micrograms/kg poly ICLC, and serum IFN levels were determined serially every 4 h for 16 h. Men and women produced substantial levels of IFN at 8, 12, and 16 h after infusion, but levels in men were consistently and significantly higher (p less than 0.05). Interferon responses were examined also in 3 male and 3 female Rhesus monkeys. Serum samples were obtained 8 and 24 h after i.v. injections of 1 mg/kg of poly ICLC. Again, there were significantly higher levels of IFN in males. The observed differences may reflect sex-linked differences in either drug metabolism or specific sensitivity to IFN induction by poly ICLC. The most interesting possibility is that the difference is due to a more general difference in IFN response between males and females. Studies are currently in progress to evaluate these possibilities.

Animals↗

A preliminary trial of poly(I,C)-LC in multiple sclerosis.

An open Phase I trial of poly(I,C)-LC in multiple sclerosis was conducted. Serious temperature elevations were typical and associated with transient accentuation of neurological dysfunction which required intensive nursing care, but no permanent complications to the treatment were observed. A regimen was developed for management of the side effects and reducing patient discomfort. Although there was a suggestion of stabilization of the disease in some patients, a conclusion about efficacy cannot be reached without a controlled trial. Future use of poly(I,C)-LC in multiple sclerosis should be confined to experimental trials in a research setting.

Carboxymethylcellulose Sodium↗

Augmented anti-acetylcholine receptor response following long-term penicillamine administration.

Because of the association of D-penicillamine (DP) therapy with myasthenia gravis, we have studied long-term DP treatment in five inbred strains of mice with doses comparable to those used in patients with rheumatoid arthritis. No clinical weakness or anti-acetylcholine receptor (AChR) antibody developed with up to 6 months of treatment, but augmented responses did occur to challenge with purified AChR in adjuvant. Anti-AChR antibody titers in C57BL/6 and C3H/He mice were significantly higher after challenge with AChR in DP-treated than in control mice. Augmented anti-AChR titers were not seen in strain A mice, but after 6 months of DP treatment increased susceptibility developed to the induction of experimental autoimmune myasthenia gravis. Nine weeks after challenge with purified AChR, 10 of 11 mice developed clinical weakness, leading to death in 6. Results of edrophonium testing were positive in 5 of 6 mice, and electrophysiological abnormalities were demonstrated in 3 of the surviving mice. Long-term DP treatment is associated with augmented anti-AChR antibody responses in C3H/He and C57BL/6 mice, and increased susceptibility to experimental autoimmune myasthenia gravis in strain A mice.

Animals↗

Occurrence of oligoclonal bands in multiple sclerosis and other CNS diseases.

The results of cerebrospinal fluid agarose gel electrophoresis in 300 consecutive patients were correlated with neurological examinations and diagnoses, other cerebrospinal fluid studies, and the results of evoked potential examinations. The presence of oligoclonal bands was the most sensitive test for multiple sclerosis (MS); bands were present in from 100% (11/11) of patients with definite MS to 82% (27/33) of those with possible MS (classified by McAlpine criteria). The visual evoked response was the next most sensitive study. Thirty-eight patients without MS or related disorders had bands in the IgG region. Three patients had plasma cell dyscrasias. Seven patients had thick single bands. Single bands did not correlate with chronic polyneuropathy but appeared to be an artifact of storage. Twenty-eight patients had active neurological disease, including cerebral infarction (in 5), viral infection (in 4), remote effect of carcinoma (in 4), and acute and chronic polyneuropathies (in 6). In acute illnesses (i.e., vascular insults), repeat electrophoresis showed disappearance of bands. In continually active disease, bands persisted. These results indicate that the presence of oligoclonal bands provides sensitive supporting evidence for the diagnosis of MS but that bands may be present in other disorders, including those not directly related to infection or abnormal immune response. The data suggest that oligoclonal bands may represent an immune response to neurological injury that is prominent in disorders with a particularly intense or continuous antigenic stimulus.

Central Nervous System Diseases↗

Prognosis of ocular myasthenia.

A retrospective study of 108 patients with myasthenia gravis who had solely ocular symptoms and signs at onset was carried out to identify factors influencing prognosis. Increasing duration of pure ocular myasthenia was associated with a decreasing risk of late generalized symptoms; only 9 (15%) of the observed generalizations occurred after more than 2 years of solely ocular symptoms. Increasing age at onset was associated with greater risk of respiratory crisis or death caused by myasthenia, whereas patients younger at onset had a greater chance of a benign outcome. Neither systemic curare tests nor responses to repetitive nerve stimulation had prognostic value.

Adolescent↗

Penicillamine-induced myasthenia gravis: effects of penicillamine on acetylcholine receptor.

Autoimmune diseases, including myasthenia gravis, occur in patients treated with D-penicillamine. Because D-penicillamine might induce autoantibodies by the mechanism of antigenic alteration, we studied the reaction of D-penicillamine with purified acetylcholine receptor from Torpedo californica. We found that brief exposure to D-penicillamine resulted in its covalent attachment to two receptor subunits, alpha (40,000 daltons) and gamma (59,000 daltons), presumably by reduction and formation of mixed disulfides. Furthermore, D-penicillamine treatment resulted in a dramatic modification of the equilibrium acetylcholine binding properties of both purified receptor and receptor-rich membrane fragments.

Acetylcholine↗

Epidural metastasis by Wilms' tumor.

Metastatic spread is common in Wilms' tumor, but spinal epidural involvement is rare. We studied two patients in whom spinal cord compression developed during treatment of Wilms' tumor. Both patients had back pain and new pulmonary metastases months after the primary diagnosis was established. One case had evidence of adjacent vertebral involvement, and successful therapy was begun while the patient had minimal neurological deficits. The second patient had back pain initially without neurological deficit or abnormality on plain spine films, followed in one month by a rapid neurological deterioration. Despite a slow and nearly complete recovery after treatment with laminectomy, radiotherapy, and chemotherapy, her condition relapsed one year later, with a compressive lesion at a higher level. Our experience stresses the importance of early recognition of treatment of this complication of Wilms' tumor.

Back Pain↗

Effect of protein kinase modulators on the regulation of cathepsin B activity in THP-1 human monocytic leukemia cells.

Cathepsin B (CB), a lysosomal cysteine proteinase, is implicated in cancer metastasis and inflammatory tissue injury. We examined the effects of the protein kinase agonists and inhibitors on the regulation of CB activity in THP-1 human monocytic cells by two macrophage activators, lipopolysaccharide (LPS) and interferon- (IFN- ). CB elevation induced by LPS alone or LPS followed by IFN- was blocked by protein kinase C (PKC) inhibitors staurosporine, H-7, phloretin and bisindolylmaleimide, and by cyclic nucleotide-dependent protein kinase inhibitors HA 1004, H-8, H-89 and cAMP-dependent protein kinase (PKA) inhibitor. The CB activity by LPS and IFN- were augmented by diacylglycerol kinase inhibitor. PKC activator, phorbol 12-myristate 13-acetate (PMA) and PKA activator, dibutyryl cAMP could replace LPS in priming the cells for IFN- stimulation but 8-bromo-cGMP did not. These findings suggest that the activation of PKC and PKA appears to be involved at least in part in the induction of CB activity in THP-1 cells.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗