Biomedical subjects

L Salford

Publications and source records attributed to L Salford.

6 recordsLinked to original sources

PubMed1993

Immunization with mutagen-treated (tum-) cells causes rejection of nonimmunogenic rat glioma isografts.

The ethyl-N-nitrosourea-induced rat glioma N32 was treated with the mutagenic compound N-methyl-N'-nitro-N-nitrosoguanidine and the surviving cells cloned by limited dilution. Out of 20 clones tested 8 did not produce tumors subcutaneously even after challenge doses 3 log units above the minimal tumor dose for N32. All of 5 clones grew in a retarded manner intracerebrally but produced tumors in some animals. Preimmunizations with three of the rejected clones (tum-) gave protection against subcutaneous and intracerebral isografts of the unmutated N32. This effect could be enhanced if the cells used for immunizations were pretreated with interferon gamma (IFN gamma) for 48 h. If immunizations were started subsequent to challenge, only immunization with one of two tested tum- clones pretreated with IFN gamma induced significant rejection against intracerebral N32 isografts. Both N32 and its tum- clones were MHC class I positive and MHC class II negative. IFN gamma treatment enhanced the MHC class I expression with 20%-90% on the tum- clones and with 40% on N32. MHC class II expression could be induced on N32 cells after 7 days of IFN gamma treatment but not on any of the tum- clones tested. We conclude that the enhancing effect of IFN gamma treatment on tumor isograft rejection may depend on up-regulation of MHC class I but not of MHC class II. This investigation demonstrates that it is possible to induce rejection of weakly immunogenic intracerebral brain tumors by immunization with selected highly immunogenic tumor cell mutants. In conjunction with relevant cytokines, the cross-protective effect of these tum- variants might be further enhanced and serve as a model for immunotherapy against malignant human brain tumors.

Animals↗

PubMed1989

Adenosine diphosphate ribosyl transferase responses to a standardized dose of hydrogen peroxide in the mononuclear leukocytes of patients with a diagnosis of cancer.

Mononuclear leukocytes from 151 patients with cancer of various organs and from 467 apparently cancer-free individuals were exposed, in vitro, to H2O2 (100 microM) and the effects of the exposure on the activity of adenosine diphosphate ribosyl transferase (ADPRT) were determined. First, the reproducibility of this test procedure was established as satisfactory, by comparing the results of assays performed independently by two investigators, and by measuring ADPRT in cells from two individuals over a 9-week period. The test data were analyzed by multiple linear regression, and the correlation of cancer diagnosis, age, sex and smoking habits with ADPRT values was determined. The strongest correlate was cancer diagnosis. We considered categorizing ADPRT values as high and low, with a cut-off value that would substantially distinguish cancer from cancer-free individuals. When a cut-off value of 1200 c.p.m. TCA ppt [3H]NAD+/5 x 10(5) cells was applied to the complete test material, it was found that ADPRT values from cancer patients were more frequently below the cut-off than values from disease-free individuals: the relative risk estimate (odds ratio) was 13.8. When a similar analysis was done on values from lung cancer patients and smoking disease-free individuals, the odds ratio was 73.5. However, a cut-off value of 2000 c.p.m. TCA ppt [3H]NAD+/5 x 10(5) cells was most effective in distinguishing lung cancer patients (the largest cancer group, n = 96) from smoking non-cancer individuals: that value provided better sensitivity (85%) and specificity (81%) than other cut-off values tested in the range 1200-2000 c.p.m. Further, in the case of lung cancer, possible effects of anatomical site, and of staging and pathology on ADPRT values was analyzed by the chi-squared test: no significant associations were found. These data support the value of the ADPRT test in detecting early stage lung cancer regardless of location or pathological type.

Adult↗

PubMed1984

Sturge-Weber disease--neurophysiological evaluation of a case with secondary epileptogenesis, successfully treated with lobe-ectomy.

A case of Sturge-Weber's disease with a generalized seizure at 7 months of age is described, followed 7 months later by the development of very frequent and therapy resistent myoclonic astatic fits. The neurophysiological evaluation indicated a primary lesion in the right occipital area followed by signs of secondary epileptogenesis. The patient was cured by a right-sided occipital lobe-ectomy including an area of leptomeningeal angiomatosis.

Angiomatosis↗

PubMed1982

[Laser surgery].

Explore the source record for details and available documents.

Argon↗

PubMed1978

Redundant nerve roots of the cauda equina. A report of five cases.

Five personally examined cases of redundant nerve roots of the cauda equina are added to the 13 hitherto on record. Except for segmental neurological deficits, intermittent claudication-like symptoms of the cauda equina dominated the histories of four of our five cases. The diagnosis was confirmed at surgical exploration, which included laminal and dural decompression. At follow-up (two months--three years) the neurological deficit, or the intermittent claudication, or both, had improved in all our patients. The pathogenesis of root redundancy is obscure. It seems that the symptoms arise through the action of at least two factors viz compression of the spinal content and the existence of one or more redundant roots. Wider use of diagnostic aids and surgical exploration would probably show that redundant roots are more common than hitherto supposed.

Aged↗

PubMedDate not supplied

Hydra head activator-like immunoreactivity in human brain astrocytomas grade III-IV and the surrounding brain tissue.

We have developed a specific and sensitive radioimmunoassay for the hydra head activator neuropeptide (HHAP). The antibody recognizes the C-terminal portion of HHAP and shows no cross-reactivity with other neuropeptides. The assay allows measurement of HHAP-like material in tissue extracts with a minimum detectable concentration of 22 fmol/ml standard HHAP (2 fmol/tube). The concentration of immunoreactive (IR) HHAP in histopathologically characterized tissues was determined in 43 specimens from astrocytomas grade III-IV and surrounding brain tissue from 18 patients. Twenty-two control specimens of gray and white matter and five from hypothalamus were taken from 5 brains at autopsy. The concentration of IR-HHAP in the brain tumors, including the actively growing tumor front, is lower than in normal brain, and thus appears not to act as a growth factor. High performance liquid chromatography (HPLC) of extracts of hypothalamus and tumors revealed two major peaks of IR-HHAP; one eluted with the same elution volume as synthetic HHAP. HPLC of cerebral cortex extracts revealed only one major peak of IR-HHAP eluting close to the void volume, which may indicate a posttranslational processing variability of HHAP in different brain regions. By immunocytochemistry HHAP immunoreactivity was localized to the cytoplasma of neuroectodermal cells.

Amino Acid Sequence↗