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Biomedical subjects

C B Wilson

Publications and source records attributed to C B Wilson.

At least 343 records · Page 19Linked to original sources

Prediction of tumor doubling time in recurrent meningiomas. Cell kinetics studies with bromodeoxyuridine labeling.

Eight patients with recurrent meningiomas (four malignant, two hemangiopericytic, and two nonmalignant) were given intravenous bromodeoxyuridine (BUdR), 200 mg/sq m, at the time of surgery to label cells in the deoxyribonucleic acid (DNA) synthesis phase; labeled cells were detected in excised tumor specimens by immunoperoxidase staining using anti-BUdR monoclonal antibody. These tumors showed a wide range of BUdR labeling indices (LI's), calculated as the percentage of BUdR-labeled cells divided by the total number of cells scored, from 0.3% to 5.4%. The tumor doubling times (Td's), estimated from serial computerized tomography scans, ranged from 8 to 440 days and showed a close inverse correlation with the BUdR LI's. A semilogarithmic linear regression analysis of these values yielded a correlation coefficient of 0.99. Tumor doubling time (Td) can be estimated using the formula: Td = 500 X Exp (-0.73 X LI), where Exp signifies the natural log base. By predicting the growth rate of meningiomas, the BUdR LI may supplement histopathological diagnosis and improve both the determination of prognosis and the design of treatment modalities in individual patients.

Adult↗

Computerized tomography in the prognosis of malignant cerebral gliomas.

Ninety-seven patients with supratentorial malignant gliomas who received postoperative radiation therapy and chemotherapy at the University of California, San Francisco, from 1977 through 1984 showed improvement in their follow-up computerized tomography (CT) scans. Twenty-one of these 97 "CT responders" were designated "complete responders" because on serial CT scans they had complete disappearance of the tumor mass and contrast enhancement, which had been present postoperatively. In the remaining 76 patients, CT scans showed reduction in the size, but not disappearance, of the lesions, and these were designated "partial responders." Fifty-eight partial responders had glioblastoma multiforme (GM); their median survival time was 72 weeks. The median survival time for the 11 complete responders with GM has not yet been achieved, but survival at the 53rd percentile is 172 weeks. Among patients with highly anaplastic astrocytoma, the median survival time was 211 weeks for the 10 complete responders and 125 weeks for the 18 partial responders. Eleven of the 21 complete responders are alive at a median postoperative follow-up time of 163 weeks (range 114 to 470 weeks). Eighteen of these patients had subtotal resection of tumor; three patients had gross total tumor resections, but postoperative CT scans showed evidence of residual or possibly recurrent tumor within 1.5 to 4.5 months. Resolution of the tumor mass and contrast enhancement took 9 to 151 weeks; the time to resolution did not depend upon the configuration of the remaining tumor mass and contrast enhancement after surgery. In this study, patients with malignant gliomas whose CT scans eventually showed sustained complete disappearance of the tumor mass and contrast enhancement had a more favorable prognosis than did patients whose CT scans showed improvement, but not complete disappearance, of the tumor. These CT findings may prove useful in determining the prognosis of patients with malignant gliomas.

Adolescent↗

An immunopathologic study of a 330-kD protein defined by monoclonal antibodies and reactive with anti-RTE alpha 5 antibodies and kidney eluates from active Heymann nephritis.

There is evidence indicating that the glomerular Ig deposits of Heymann's nephritis (HN)--a model of epimembranous glomerulonephritis--may be formed at least in part in situ by binding of free circulating antibody with brush border (BB) antigen expressed by glomerular epithelial cells. In this work, we provide evidence that a 330-kD protein defined by seven monoclonal antibodies is responsible for HN. 1) Ig eluted from glomeruli of rats with HN induced classically with crude BB preparation bind specifically the 330-kD antigen; 2) passive immunization with monoclonal antibodies induces epimembranous glomerular Ig deposits; 3) active immunization with the 330-kD antigen induces proteinuric glomerulonephritis; 4) the 330-kD antigen was present in the nephritogenic preparation purified by Edgington, Glassock, and Dixon, because it was identified by the corresponding heterologous antisera. These results, obtained by a completely different approach, confirm and extend those of Kerjaschki and Farquhar and provide a link with the classical studies on HN.

Animals↗

Northern California Oncology Group protocol 6G91: response to treatment with radiation therapy and seven-drug chemotherapy in patients with glioblastoma multiforme.

The Northern California Oncology Group (NCOG) conducted a nonrandomized phase II study to evaluate the benefit of a seven-drug chemotherapy protocol (NCOG 6G91) in patients with glioblastoma multiforme (GM). Time to tumor progression was the primary end point of the study. The treatment consisted of 5-FU and lomustine administered after surgery and before radiation therapy, hydroxyurea and misonidazole during radiation therapy, and procarbazine and vincristine alternated with carmustine and 5-FU after radiation therapy. Ninety patients entered the study; data from the 64 patients with GM who completed radiation therapy and at least started the postradiation chemotherapy regimen and returned for follow-up examination are analyzed in this report. The median time to tumor progression in the 64 adequately treated patients was 42 weeks; the 25th percentile value was 60 weeks. A Cox multivariate analysis showed that age and extent of surgical resection were important prognostic variables in patients with GM. The results of this treatment regimen were similar to those of a previous NCOG protocol (6G61), which consisted of hydroxyurea during radiation therapy followed by chemotherapy with carmustine or a combination of lomustine, procarbazine, and vincristine.

Adult↗

Establishment and characterization of a cell line from a human gliosarcoma.

A human gliosarcoma culture was characterized from the time of inception to the time of establishment of the cell line (SF-539 BT). Immunohistochemical analysis of the original tumor showed 2 distinct regions of cells. The gliomatous regions were identified by immunostains for glial fibrillary acidic protein and the sarcomatous regions by immunostains for laminin, collagen type IV, procollagen type III, and fibronectin. In early-passage culture, both types of cells maintained their characteristic immunohistochemical profiles; however, after the fourth subcultivation in monolayer culture, no cells expressing glial fibrillary acidic protein could be identified. All cells had become morphologically uniform and expressed laminin, collagen type IV, procollagen type III, and fibronectin only. The immunostaining profile of clones grown in soft agar was similar to that of cells in monolayer culture. At establishment, SF-539 BT has a saturation density of 1.3 X 10(6) cells/25 sq cm, a doubling time of 32 h, and a plating efficiency of 22% in monolayer culture. The tumor cell line is resistant to 1,3-bis(2-chloroethyl)-1-nitrosourea, has an abnormal karyotype, grows anchorage independently, and forms a tumor that most closely resembles a spindle cell sarcoma in athymic mice. Its ultrastructure in monolayer culture consists of large cells with an expanded rough endoplasmic reticulum and abundant multivesicular bodies; in athymic mice, extracellular collagen fiber formation is prominent. DEAE-cellulose chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis of cultures labeled with [3H] proline demonstrated interstitial collagen formation. We conclude that the cell line at establishment is a collagen-producing spindle cell sarcoma that resembles the sarcomatous regions of the original mixed tumor. Further cell separation and characterization studies are needed to determine the pathogenesis of mixed tumors such as gliosarcoma.

Animals↗

A cell kinetic study on medulloblastomas.

The cell kinetics of medulloblastoma were studied to define characteristic proliferation for comparison with other neuroectodermal tumors. Four patients with cerebellar medulloblastoma received 3H-thymidine intravenously 1 to 2 days before surgery. Biopsy specimens from each tumor were processed for autoradiography. The respective average labeling indices were 14.4%, 14.1%, and 11.2% in the three mid-cerebellar medulloblastomas and 8.0% in the cerebellar hemispheric medulloblastoma. The mean survival time with various treatments including radiation therapy before or after the study in these four patients was 6 years (range, 3-9 years). In contrast, patients with malignant gliomas that had a labeling index greater than 5% died within 1 year. This difference in survival was attributed to the greater sensitivity of medulloblastoma to radiation therapy.

Adolescent↗

Tubulointerstitial nephritis induced in the brown Norway rat with chaotropically solubilized bovine tubular basement membrane: the model and the humoral and cellular responses.

Doses of as little as 50 micrograms of a soluble chaotropic extract of bovine tubular basement membrane (Bov-KBr-TBM) with adjuvants induced anti-TBM antibodies and tubulointerstitial nephritis (TIN) in Brown Norway (BN) rats. The lesion was shown by renal histology, by deposition of IgG and C3 along TBM, and in terms of the humoral and cellular immune responses to compare to that produced by the standard immunization (particulate bovine TBM) for this model of TIN in BN rats. More than half of the mononuclear cells in kidneys of BN rats with TIN bore various T-cell antigens (monoclonal antibodies W3-13, W3-25, and OX-8), and most of the infiltrating cells were positive for Ia (monoclonal antibody OX-6) by indirect immunofluorescence. Purified suspensions of these mononuclear infiltrates were prepared by using Ficoll-Hypaque gradients and the fluorescence-activated cell sorter (FACS) to eliminate renal tubular epithelial cells. The purified mononuclear cells, cultured for 5 days, incorporated thymidine in response to concanavalin A (Con A), Mycobacterium tuberculosis purified protein derivative, and Bov-KBr-TBM but not in response to a variety of autologous renal antigens. After culture for 5 days in Bov-KBr-TBM and Con A supernatant, lymph node cells (LNC) from Bov-KBr-TBM-immunized BN rats passively transferred TIN to naive BN rats. Although no cells reactive with autologous renal antigens were detected in the renal infiltrates, the transfer of disease with propagated LNC suggests that elements of the cellular immune system, in addition to anti-TBM antibody, contribute to the generation of this BN-TIN.

Animals↗

Characterization of immunoreactive beta-endorphin secreted from cultured human corticotropin-secreting adenomas.

Seven human corticotropin-secreting adenomas causing Cushing's disease or Nelson's syndrome were maintained in long-term culture. Pooled media from the individual adenomas were analyzed for the composition of their secretory products. From a radioimmunoassay (RIA) with 100% cross-reactivity for human beta-endorphin (beta h-EP) and beta-lipotropin (beta h-LPH), immunoreactive beta h-EP (IR X beta h-EP) was found to be the predominant secretory product after Sephadex G-50 analysis in 4 cases (40-80% of total IR), immunoreactive beta h-LPH (IR X beta h-LPH) predominated in 1 case, and both were equipresent in 2-cases. IR X beta h-EP was further purified by high-performance liquid chromatography (HPLC) and analyzed in 4 cases with ion-exchange chromatography on SP-Sephadex C-25 and a RIA which completely cross-reacts with beta h-EP, [N alpha-Ac]-beta h-EP, beta h-EP-(1-27) and [N alpha-Ac]-beta h-EP-(1-27). In all cases, the IR X beta h-EP was the main component (40-70%); the remaining IR material was attributable partially to [N alpha-Ac]-beta h-EP or other, less defined immunoreactive material. In 3 cases, enough IR X beta h-EP material was available for HPLC and to perform a radioreceptor assay using tritiated beta h-EP as primary ligand. The displacing potency of these preparations relative to synthetic beta h-EP was related to the content of the immunoreactive component eluting in the position of synthetic beta h-EP.

Adenoma↗

Clinical pharmacology of extended-spectrum penicillins in infants and children.

Compared with previously available penicillins, piperacillin, azlocillin, and mezlocillin have increased activity in vitro against gram-negative bacilli. After intravenous administration of conventional doses (50 to 100 mg/kg) in children, peak concentrations of these drugs are approximately 70 to 350 micrograms/ml. For piperacillin, azlocillin, and mezlocillin, the half-lives during the beta elimination phase (t 1/2 beta) are approximately 0.5 to 0.75, 0.8 to 1.7, and 0.8 to 1.0 hours, respectively. In patients receiving the higher dosage, particularly of azlocillin, the t 1/2 beta may be prolonged by approximately 20%. A total daily dosage of 300 mg/kg or 9 gm/m2 given in four to six divided dosages should produce peak concentrations of approximately 150 micrograms/ml, and concentrations greater than 16 micrograms/ml for at least 2 hours after each administration. Lower daily dosages are needed in neonates, but precise dosage recommendations cannot be made at this time. Only approximately 60% of piperacillin and approximately 45% of azlocillin are eliminated unchanged in the urine; thus only modest dosage reductions are needed in patients with decreased renal function. In children, adverse effects have been infrequent.

Absorption↗

Effect of leukocyte depletion on glomerular dynamics during acute glomerular immune injury.

Large doses of anti-glomerular basement membrane antibody (AGBM-Ab) have been shown consistently to decrease both single nephron filtration rate (SNGFR) and the glomerular ultrafiltration coefficient (LpA) within 60 min of administration of the antibody. Both the decrease in SNGFR and LpA may be the result of infiltration of leukocytes blocking capillary loops and/or endothelial cell separation from the glomerular basement membrane through leukocyte dependent activated cytotoxic products or by mechanisms associated with leukocyte activation and infiltration. Administration of 2.5 micrograms/g body wt AGBM-Ab was performed in 10 control Munich-Wistar rats and in six Munich-Wistar rats in which 3 to 5 days prior to micropuncture experiments the rats were splenectomized and then irradiated to produce leukocyte depletion. Micropuncture measurements were performed in a condition of plasma volume expansion both prior to and after AGBM-Ab administration. In the control group, SNGFR decreased from 64 +/- 3 to 48 +/- 2 nl/min X g kidney wt after AGBM-Ab administration due to a decrease in LpA from 0.13 to 0.06 nl X sec-1 X mm Hg-1 X g kidney wt-1. This decrease in either SNGFR or LpA did not occur in the leukocyte depleted group. Linear deposits of IgG and C3 were similar in both groups. Polymorphonuclear leukocytes were significantly decreased in glomerulus from 7.4 +/- 0.7 in control vs. 0.7 +/- 0.3 in leukocyte depletion (P less than 0.01). There was no difference in glomerular dynamics between controls and leukocyte depleted rats prior to AGBM-Ab administration.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Comparative susceptibility of group B streptococci and Staphylococcus aureus to killing by oxygen metabolites.

Group B streptococci (GBS) lack catalase, and they produce and release H2O2;thus, they should be readily killed by phagocytes with a diminished respiratory burst. Surprisingly, although strains of Staphylococcus aureus were killed at H2O2 concentrations greater than 0.5 mM, GBS strains were killed only at concentrations greater than 5mM. In contrast, GBS were killed by hydroxyl radicals generated by the xanthine oxidase-acetaldehyde system at O2 fluxes greater than or equal to 3.5 nmol/ml per min, whereas O2 fluxes greater than or equal to 10 nmol/ml per min were required to kill the S. aureus strains. Results with virulent and laboratory strains of GBS were similar. The differences in susceptibility of GBS and S. aureus seemed to correlate with differences in content of endogenous oxygen-metabolite scavengers. GBS contained approximately 100-fold more glutathione and approximately 20-fold more glutathione reductase than did S. aureus, whereas S. aureus was rich in catalase that GBS lacked. GBS that were grown in buthionine sulfoximine, however, contained 87% less glutathione than did controls but were not more susceptible to killing by H2O2 or the xanthine oxidase-acetaldehyde system. Similarly, the relative susceptibility of GBS to tert-butyl hydroperoxide and H2O2 paralleled that of S. aureus. Thus, inherent differences in susceptibility of vital cellular functions to oxidative damage rather than content of oxygen-metabolite scavengers may account for the differences in susceptibility of GBS and S. aureus.

Acetaldehyde↗

Therapy of anti-glomerular basement membrane antibody disease: analysis of prognostic significance of clinical, pathologic and treatment factors.

We have compared the effect of therapy with immunosuppression alone to immunosuppression plus plasma exchange on the clinical course and rate of disappearance of antibody in 17 patients with anti-glomerular basement membrane (anti-GBM) antibody-induced renal disease. Patients receiving immunosuppression (n = 9) and those receiving plasma exchange (n = 8) were similar in terms of entry clinical characteristics, pulmonary manifestations and complications associated with therapy. Rate of disappearance of anti-GBM antibody as estimated from serial estimates of antibody binding was significantly more rapid in patients receiving plasma exchange, and mean serum creatinine in these patients at end of therapy was half that of the patients receiving immunosuppression alone. Analysis of clinical and pathologic values at study entry, however, indicated that the percent of crescents on initial renal biopsy and entry serum creatinine correlated better with outcome than did therapeutic modality. Thus, though plasma exchange may offer some advantage over immunosuppression alone in the treatment of this disease, degree of pathologic involvement appears to be the major factor affecting outcome. Patients with low cresents (less than 30%) and well preserved function did well with either treatment, while patients with severe crescentic involvement and impaired glomerular filtration rate did poorly.

Adolescent↗

Activation of neonatal and adult human macrophages by alpha, beta, and gamma interferons.

Increasing evidence suggests that gamma interferon (IFN-gamma) is the major or sole factor in human lymphokines which activates blood monocyte-derived macrophages (M phi) to inhibit or kill Toxoplasma gondii and certain other intracellular pathogens. In the current studies, we found that IFN-gamma effectively activated tissue M phi from adults (peritoneal M phi) and from newborns (placental M phi) as well as blood-derived M phi from adults and from newborns to kill or to inhibit the replication of T. gondii. Results with purified and recombinant IFN-gamma and with adult and newborn M phi were similar. IFN-gamma-treated M phi were equally or more active against T. gondii than were freshly isolated monocytes and M phi. Recombinant IFN-alpha A and IFN-beta were less effective than IFN-gamma. IFN-gamma also inhibited survival and replication of T. gondii in WISH cells more effectively than did IFN-alpha and IFN-beta. These findings are consistent with an important role for IFN-gamma in the control of Toxoplasma infection and indicate that the anti-Toxoplasma activity of resting and IFN-gamma-activated adult and neonatal M phi is similar. The increased susceptibility of neonates to T. gondii is not due to a defect in M phi effector function.

Adult↗

Nephroimmunopathology and pathophysiology.

Immunologic models of renal injury are useful in the study of pathophysiology. Some of these models have already been used in glomerular micropuncture studies and were shown to be approachable with the same techniques that were developed to study normal renal function. The typical decrease in the glomerular permeability coefficient found in such studies is countered by an increase in the hydrostatic pressure gradient, minimizing decreases in single nephron filtration rate. Antibody mechanisms involving either direct glomerular (and tubular) fixation of antibody or accumulation of immune complex materials provide an array of acute and chronic lesions for evaluation with relevance to the bulk of immune glomerular and tubular lesions in humans. The influences of varied and overlapping immune mediator systems are also useful areas for physiologic assessment. The tools of the renal immunopathologist may be useful to the physiologist in identifying and localizing the effects of transport systems central to renal function. The collaborative interaction of investigators skilled in immunology, pathology, and physiology is necessary to achieve optimum scientific value.

Animals↗

Characterization of dopamine and alpha-adrenergic receptors in human prolactin-secreting adenomas with [3H]-dihydroergocryptine.

One tenable hypothesis for the etiology of the development of prolactin-secreting adenomas is that a decrease in inhibitory dopaminergic regulation leads to increased lactotroph proliferation. Dopamine receptors have been repeatedly characterized on prolactin-secreting adenomas using labelled antagonists as ligands; however, no data are available on characterization of the receptor with a dopaminergic agonist. An agonist was utilized as the radioligand in the present study to permit the direct comparison of the pharmacological characteristics of the binding site with the biological response, the inhibition of prolactin secretion. This comparison has never been reported in tissues from the same species. Binding of the dopamine agonist and alpha-adrenergic antagonist [3H]-dihydroergocryptine ([3H]-DHE) to particulate fractions of surgically resected human prolactin-secreting adenomas was high affinity, monophasic, and saturable. Careful characterization of the [3H]-DHE binding by competitions with a large number of dopaminergic and alpha-adrenergic agents revealed the presence of both dopaminergic and alpha-adrenergic binding sites. The presence of a saturable, high affinity alpha-adrenergic binding site was confirmed with the specific alpha-adrenergic antagonist [3H]-WB4101 as a radioligand. Although the rank order of potency for dopaminergic compounds to compete for [3H]-DHE binding was consistent with an interaction with a dopamine receptor, the inhibitory constants (Ki) calculated from the competitions were higher than expected at an anterior pituitary dopamine receptor. This appeared to be due to the lower affinity of these agents at the alpha-adrenergic sites. The observed potency of dopaminergic compounds was inversely related to the number of alpha-adrenergic sites.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenoma↗

Glomerulonephritis with absent glomerular basement membrane antigens.

This is a report of a child with glomerulonephritis and no family history of renal disease. On renal biopsy there was splitting and thinning of glomerular basement membrane antigens. These findings are similar to those seen in patients with familial nephritis and may be part of a spectrum of primary glomerular basement membrane defects.

Antigens↗

Factors related to the appearance of alveolar macrophages in the developing lung.

The numbers of alveolar macrophages (AM) are known to be low in utero and to increase rapidly after birth. This study analyzed factors related to the appearance of AM in the lungs of term and preterm monkeys (Macaca nemestrina). We found that the numbers of AM were greater at birth in term than in preterm monkeys (p less than 0.01) and that they increased with postnatal age in term animals (r = 0.86) and in preterm animals without hyaline membrane disease (HMD) (r = 0.79). In contrast, the numbers of AM did not increase with postnatal age in preterm animals with HMD (r = 0.17). By multivariant analysis, AM numbers correlated most strongly with a combination of 2 variables: lavage fluid phospholipid and absence of HMD (r = 0.996). Preparations of alveolar surface-active material from newborn monkeys and to a lesser degree from adult monkeys were found to stimulate migration and polarization of monkey AM and blood monocytes in vitro. The migration-stimulating factor(s) in alveolar surface-active material had an apparent molecular weight greater than 10,000 and appeared not to be a lipoxygenase product of arachidonic acid metabolism. These data indicate a correlation between factors regulating lung pressure-volume stability and AM numbers and are consistent with a potential role for components of alveolar surface-active material in regulating the perinatal increase in AM.

Aging↗