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Biomedical subjects

C B Wilson

Publications and source records attributed to C B Wilson.

At least 379 records · Page 21Linked to original sources
PubMed1984

Supratentorial malignant gliomas of childhood. Results of treatment with radiation therapy and chemotherapy.

Twenty-seven patients aged 1 to 18 years harboring supratentorial (20 in the cerebrum and seven in the thalamus) malignant gliomas were treated between 1975 and 1982. There were four glioblastomas multiforme, 14 anaplastic astrocytomas, and nine malignant gliomas. All patients had a subtotal resection or biopsy as the initial procedure and received postoperative radiation therapy (RT). Fifteen of 27 patients were treated by RT alone; 14 had tumor progression with a median time to tumor progression (MTP) of 65 weeks. Twelve patients were treated with chemotherapy as an adjuvant to RT; only seven had tumor recurrence, with an MTP of 130 weeks. Of the 21 patients with recurrent tumors in both groups, 18 were treated with chemotherapy alone, or chemotherapy with a second surgical procedure or second course of RT. For all histological grades of tumor, the MTP for first recurrence was 75 weeks and the median survival time was 180 weeks. Age at initial diagnosis was found to be a statistically significant prognostic factor, with patients younger than 10 years of age surviving longer than patients aged over 10 years (p = 0.02).

Adolescent↗
PubMed1984

Use of the argon surgical laser in neurosurgery.

The argon surgical laser has been used in 68 neurosurgical procedures that included the removal of intracranial and intraspinal tumors, spinal cord fenestration for syringomyelia, and the production of dorsal root entry zone lesions. Characteristics that make the argon surgical laser a useful microneurosurgical instrument include the availability of a fiberoptic delivery system, a laser spot size that can be varied continuously between 0.15 and 1.5 mm, a single laser-aiming and treatment beam, the transmission of argon laser light through aqueous media such as irrigating or cerebrospinal fluids, and improved hemostasis compared to conventional techniques. The argon laser is limited primarily by its relatively low power output (less than 16 W), which makes the excision of large tumors difficult. However, even with these limitations, which can be used to advantage in the proper setting, the authors' laboratory and clinical experience suggests that the argon surgical laser may be useful in certain microneurosurgical operations.

Adolescent↗
PubMed1984

Central nervous system mesenchymal chondrosarcoma. Case report.

Local recurrence developed 6 years after the initial resection of an intraspinal meningeal tumor that originally was thought to be an angioblastic meningioma. Histological review of the pathology led to a change of that diagnosis to one of mesenchymal chondrosarcoma. The recurrent vascular tumor was embolized, then totally excised. Because this tumor had malignant features, the patient received irradiation and chemotherapy. No evidence of regrowth has been observed during a period of more than 4 years. Mesenchymal chondrosarcomas of the central nervous system and their treatment are reviewed.

Adult↗
PubMed1984

Surgical treatment of syringomyelia. Favorable results with syringoperitoneal shunting.

The authors reviewed the clinical findings, radiological evaluation, and operative therapy of 39 patients with syringomyelia. Syringoperitoneal (SP) shunting was used in 15 patients and other procedures were used in 24 patients. Follow-up periods ranged from 1 1/2 to 12 years. During the period of this study, metrizamide myelography in conjunction with early and delayed computerized tomography scanning replaced all other diagnostic procedures in patients with syringomyelia. Preoperative accuracy for the two procedures was 87%. The most common symptoms were weakness (79%), sensory loss (67%), pain (38%), and leg stiffness (28%). Surgery was most effective in stabilizing or alleviating pain (100%), sensory loss (81%), and weakness (74%); spasticity, headache, and bowel or bladder dysfunction were less likely to be reversed. Approximately 80% of patients with idiopathic and posttraumatic syringomyelia and 70% of those with arachnoiditis improved or stabilized. Better results were obtained in patients with less severe neurological deficits, suggesting the need for early operative intervention. A higher percentage of patients had neurological improvement with SP shunting than with any other procedure, especially when SP shunting was the first operation performed. Patients treated with SP shunts also had the highest complication rate, most often shunt malfunction. These results indicate that SP shunting is effective in reversing or arresting neurological deterioration in patients with syringomyelia.

Adolescent↗
PubMed1984

A decade of pituitary microsurgery. The Herbert Olivecrona lecture.

The author reviews his experience with surgical treatment of 1000 pituitary tumors, the majority of which were endocrine-active. The criteria of grading, the microsurgical technique used, and the postoperative results are presented. The mortality rate was 0.2% overall, with no deaths in the group of 774 patients with endocrine-active adenomas.

Acromegaly↗
PubMed1984

Intracranial dissecting aneurysms of the posterior circulation. Report of six cases and review of the literature.

Dissecting aneurysms of the intracranial posterior circulation are unusual lesions that affect otherwise healthy young adults, are difficult to diagnose and manage, and carry a high morbidity and mortality rate. Headache in the suboccipital-posterior cervical region is the most common presenting symptom. The dissection usually occurs between the intima or internal elastic lamina and the media; subadventitial dissection does occur and accounts for the infrequent finding of subarachnoid hemorrhage. A deficit in the inner layers of the vessel is the proposed source of dissection. The angiographic features are inconsistent, although an irregularly narrowed arterial segment with proximal and/or distal dilatation are typical findings. Depending on the location of the dissection, the surgical options are: ligation, trapping, or reinforcement of exposed abnormal portions of the vessel. Anticoagulation therapy is not indicated in the management of this lesion.

Adolescent↗
PubMed1984

Phase II evaluation of dibromodulcitol in the treatment of recurrent medulloblastoma, ependymoma, and malignant astrocytoma.

The authors have conducted a Phase II trial to evaluate orally administered dibromodulcitol in the treatment of 40 evaluable patients with recurrent medulloblastoma, ependymoma, and malignant astrocytoma. Ten of 20 patients harboring medulloblastoma responded to therapy with a median time to tumor progression (MTP) of 40 weeks, and four of 20 patients had no sign of progression of disease 4 years after treatment was begun. The MTP for all 12 patients with ependymoma was 30 weeks. Nine of these 12 patients had stabilization of their disease with an MTP of 67 weeks; three of these 12 patients had no signs of progression for 1 to 3 years after treatment was begun. Of six patients harboring supratentorial gliomas, none responded to dibromodulcitol. Two patients, one with a primitive neuroectodermal tumor and the other with a metastatic carcinoma of the breast, had stabilization of disease for more than 4 and 2 years, respectively.

Adolescent↗
PubMed1983

Improvement in survival produced by sequential therapies in the treatment of recurrent medulloblastoma.

Thirty-six patients with recurrent medulloblastoma were treated with various combination chemotherapy protocols after initial treatment (usually irradiation) failed. Use of systemic chemotherapy was limited by depressed bone marrow reserves secondary to previous craniospinal irradiation. Intraventricular and intrathecal therapies included cytosine arabinoside (Ara-C), methotrexate, and thio-tepa given as single agents. Major systemic agents used alone or in combination included CCNU, procarbazine, vincristine, and the hexitol epoxides. Patients were reirradiated with or without misonidazole when there was definite tumor progression after all other therapies failed and/or because myelosuppression was so severe that further chemotherapy was not possible. Sequential systemic or intrathecal chemotherapy and reirradiation produced median survivals of two years and 25% quartile survivals of 2.9 years. The prognosis for patients harboring recurrent medulloblastoma has improved considerably over the years because of the therapeutic approaches reported here.

Adolescent↗
PubMed1983

Isolation, purification and characteristics of mononuclear phagocytes from human placentas.

Methods for the isolation of mononuclear phagocytes from human placentas by digestion with collagenase or with trypsin are described. Mononuclear phagocytes were approximately 35% of the cells obtained. Preparations were enriched for mononuclear phagocytes by sequential density gradient centrifugation over Ficoll-Hypaque and Percoll, adherence to plastic and removal of contaminating trophoblastic cells with brief trypsin exposure. Monolayers obtained by these methods were greater than 85% mononuclear phagocytes. These cells were predominantly of fetal origin; most were mature macrophages but up to 20% appeared to be recently derived from blood monocytes as determined by ultrastructural peroxidase cytochemistry.

Cell Count↗
PubMed1983

A sibship with hypokalemic alkalosis and renal proximal tubulopathy.

A new syndrome, characterized by hypokalemic alkalosis, hyperreninemia, aldosterone, high urinary prostaglandin E2 excretion, normal BP, and resistance of BP to angiotensin II is described in three of four siblings. Histologic examination of tissue obtained by biopsy from the kidneys showed an intense staining of the proximal tubular cells, as well as an extreme hypertrophy of the proximal tubular basement membranes, features that previously have not been observed. On electron microscopic examination, the characteristic changes of the tubular cells consisted of very dense cytoplasm, compact mitochondria, and pyknotic nuclei. In contrast to Bartter's syndrome, the juxtaglomerular apparatus were of normal appearance. Glomerular filtration rate and renal plasma flow were within normal limits. Fractional distal delivery of proximal tubular solute and fractional chloride reabsorption in the thick ascending limb of the loop of Henle were normal. The findings of a genetic linkage between the syndrome and the major histocompatibility system suggests that this familial tubulopathy is an inherited disorder.

Aldosterone↗
PubMed1983

Characterization of inflammatory cells in autoimmune tubulointerstitial nephritis in rats.

Brown Norway rats immunized with bovine tubular basement membrane (TBM) antigens develop tubulointerstitial nephritis. The composition of the inflammatory cell infiltrate was characterized in kidney tissue sections and cell suspensions obtained from affected kidneys. Anti-TBM antibody deposition in the kidney began 8 days after immunization and was followed on days 8 to 10 by C3 deposits and infiltration of polymorphonuclear leukocytes (PMN). After day 13, the infiltrate became almost exclusively mononuclear in character. On day 13, the inflammatory mononuclear cells recovered by Ficoll-Hypaque centrifugation contained 10% Ig+ cells (B cells), 60% W3/25+ cells (T helper cells), 9% OX8+ cells (T suppressor cells), 9% esterase+ cells (monocytes/macrophages), 4% renal cells, and 8% other unidentified cells. Monocytes/macrophages were prominent only at the latest stages of the disease. The ratio of W3/25+ to OX8+ cells was higher in the kidney than in the spleen or peripheral blood. The sequential accumulation of T cells and then monocytes/macrophages after an initial antibody, complement, and PMN lesion suggests a role for the T cells (selective prevalence of the helper T cell population over that of suppressor T cells) both as inflammatory cells and in progression and regulation of the subsequent stages of injury.

Animals↗
PubMed1983

Intracellular penetration and antimicrobial activity of antibiotics.

Delayed response or recurrence of clinical infections may, in part, be due to the inability of certain antibiotics to penetrate human polymorphonuclear leukocytes (PMN) and exert intracellular antibacterial activity. We determined the penetration of PMN by certain hydrophilic and certain lipophilic antibiotics, and assessed their activity against intracellular Haemophilus influenzae, type b or Staphylococcus aureus. We found that penicillin G was excluded from human PMN while chloramphenicol was concentrated within these cells; chloramphenicol killed significantly more intracellular H. influenzae than did penicillin or ampicillin. Clindamycin and trimethoprim penetrated into normal and chronic granulomatous disease (CGD) PMN equally and were at least transiently concentrated in the cells. Clindamycin and the combinations trimethoprim/sulphamethoxazole and trimethoprim/rifampicin were most effective in killing intracellular Staph. aureus in vitro; these antibiotics reduced the bacterial density in CGD PMN to values comparable to those in normal PMN. The mechanism by which clindamycin and rifampicin killed intracellular Staph. aureus appeared to be due to direct antimicrobial activity. Antibiotics that penetrate into phagocytes may be more effective in infections due to pathogens capable of intracellular survival.

Anti-Bacterial Agents↗
PubMed1983

Age-dependent effects of aminobutyryl muramyl dipeptide on alveolar macrophage function in infant and adult Macaca monkeys.

We compared the antimicrobial function of alveolar macrophages (AM) from adult and 3- to 5-wk-old infant primates (Macaca nemestrina) and the effects of the immunomodulator, aminobutyryl muramyl dipeptide (abu-MDP) on this function. Phagocytosis of Staphylococcus aureus (SA) and group B streptococcus (GBS) by adult and infant AM was comparable. Adult and infant AM killed SA equally within 15 min of incubation; however, after 45 min, with phagocytosis of additional bacteria, adult AM had greater bactericidal activity (p less than 0.01). The bactericidal activity of infant and adult AM against GBS was comparable after 45 min of incubation; infant AM had slightly but significantly greater bactericidal activity with short incubation (15 min; p less than 0.025). The bactericidal activity of abu-MDP-treated infant AM against SA (p less than 0.01) and GBS (p less than 0.05) was greater than that of untreated infant AM and untreated or abu-MDP-treated adult AM. The abu-MDP did not significantly (p greater than 0.2) enhance the antimicrobial activity of adult AM. Catalase, but not superoxide dismutase or mannitol, significantly (p less than 0.005) increased survival of GBS in infant AM; this effect was comparable in abu-MDP-treated and in untreated AM. The abu-MDP-treated infant, but not the adult AM, released more acid phosphatase when triggered by opsonized zymosan than did untreated AM, but superoxide anion release by infant or adult AM was not affected by incubation with abu-MDP.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1983

Activity of antibiotics in chronic granulomatous disease leukocytes.

Patients with chronic granulomatous disease (CGD) have recurrent infections with catalase-producing organisms, particularly staphylococci, that survive within their leukocytes. To be most effective, antibiotics used to treat infections in CGD patients may need to kill both intracellular and extracellular organisms. We studied the ability of certain antibiotics to penetrate normal and CGD neutrophils and to kill intracellular staphylococci. Trimethoprim and clindamycin were concentrated in normal and in CGD neutrophils; maximum cellular-to-extracellular concentration ratios of clindamycin and of trimethoprim were approximately 30 and approximately 4, respectively. In contrast, penicillin was excluded from normal neutrophils. Clindamycin, trimethoprim/sulfamethoxazole, rifampin, and trimethoprim/rifampin significantly reduced the number of viable intracellular staphylococci in normal and CGD neutrophils. After 24 h of incubation in the presence of these antibiotics, the number of viable intracellular staphylococci in normal and CGD neutrophils was similar. In contrast, dicloxacillin, gentamicin, and cephalothin had no significant effect on the number of intracellular staphylococci in normal or CGD neutrophils.

Anti-Bacterial Agents↗