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N J Olsen

Publications and source records attributed to N J Olsen.

89 records · Page 5Linked to original sources
PubMed1987

Decreased T-cell-mediated suppression of IgM--rheumatoid factor synthesis in rheumatoid arthritis.

Circulating B-cell precursors specific for rheumatoid factor (RF) are present in normal subjects but spontaneous in vitro synthesis of RF occurs only in rheumatoid arthritis (RA). The regulatory role of RF-specific suppressor T cells in this process was studied in pokeweed mitogen-stimulated in vitro cultures of peripheral blood mononuclear cells. Addition of graded numbers of suppressor T8(+) cells from RA patients to normal B cells resulted in consistently less suppression of IgM and RF synthesis than that achieved by normal suppressor T cells. A preculture system was then used to probe for RF-specific suppressor precursor lymphocytes. RA T-cell populations failed to generate normal levels of RF-specific suppression during in vitro culture for 4 days. Incubation with human-aggregated IgG (HaIgG) resulted in an increase in RF-specific suppression to normal levels. The data indicate that induction and full expression of RF-specific suppressor T-cell function is blocked in vivo in RA but can be overcome in vitro by incubation with HaIgG.

Arthritis, Rheumatoid↗
PubMed1987

Revision of failed total hip arthroplasty.

Ninety-seven revisions of total hip replacements are reviewed with a median time of observation of 47 months. Satisfactory pain relief was obtained in 86%. There were six complete failures which were reduced to three by further surgery. One hip became infected and was excised. In 12 cases the revisions were complicated by peroperative fractures and in five by dislocations. Radiographic analysis disclosed a high percentage of periarticular ossification and 25 cases of radiographic loosening of the femoral implant.

Aged↗
PubMed1987

Revision of the uncemented hip prosthesis.

In a series of 213 consecutive total hip replacements a.m. Lubinus, the clinical course after 72 revisions and 141 primary procedures was compared after 5 years. The revised THRs were uncemented Ring prostheses. Dislocation and peroperative fracture were more common in the revision group. Two failures because of aseptic loosening occurred in the revision group and 3 in the control group. No excisional arthroplasty was required, and no infections occurred. Radiographic evaluation of prosthetic positioning, component loosening, calcar resorption, and paraarticular ossification disclosed only slightly inferior results in the revision group. Clinically, the revised cases were not inferior to the primary ones. Revision of the uncemented hip seems less difficult than of the cemented hip.

Adult↗
PubMed1986

St Georg modular knee prosthesis. A two-and-a-half to six-year follow-up.

The St Georg modular knee replacement has been studied in 59 cases with an observation period ranging from 28 to 73 months. In 47% of the knees both compartments were replaced; five of the six poor results were in this group. These were revised to a hinge arthroplasty or, in one case, to an arthrodesis. Other complications were few and insignificant. There were no infections. We concluded that unicompartmental knee arthroplasty can be recommended when joint involvement is localised to one compartment only. With more generalised joint disease we prefer a semiconstrained total condylar prosthesis.

Aged↗
PubMed1985

St. Georg hinged-knee prosthesis. A 2.5- to 8-year follow-up.

Thirty-eight St. Georgs hinged-knee arthroplasties were studied with a follow-up of 2.5-8 years; 86.8% of the patients obtained an excellent or a good result, and 7.9% of the arthroplasties were failures. There was an infection rate of 3.8% and 3.8% loose prostheses. Among the failures there were two infected arthroplasties. One was arthrodesed, resulting in a pseudoarthrosis and one was successfully revised. One traumatic loosening lead to arthrodesis. It is concluded that hinged-knee arthroplasty under special circumstances may be a useful procedure.

Adult↗
PubMed1984

Decreased pokeweed mitogen-induced IgM and IgM rheumatoid factor synthesis in rheumatoid arthritis patients treated with gold sodium thiomalate or penicillamine.

Prospective and retrospective analysis of data obtained on 119 patients with rheumatoid arthritis suggested a relationship between clinical response induced by gold salts or D-penicillamine and decreased in vitro antibody synthesis by peripheral blood mononuclear cells. A subgroup of 21 patients with inactive disease receiving these drugs was found to have decreased pokeweed mitogen-induced in vitro synthesis of IgM and IgM rheumatoid factor. Detailed analysis of the cellular mechanisms responsible for this decreased responsiveness demonstrated markedly decreased B cell function. Patients treated with D-penicillamine also had altered T cell helper function manifested by incomplete reconstitution of the normal IgM response, while patients treated with gold salts had normal T cell function. Monocytes appeared not to have a major role in the decreased in vitro responsiveness. The results suggest that, in patients who respond to gold salts or D-penicillamine, antibody synthesis by circulating B cells is profoundly decreased, probably due to an indirect effect of these disease-modifying agents.

Arthritis, Rheumatoid↗
PubMed1978

Cushing's syndrome due to adrenal adenoma with persistent diurnal cortisol secretory rhythm.

A 41-yr-old female with presumed Cushing's syndrome was found to have a diurnal cortisol rhythm characterized by low values of 8:00 a.m. and consistently high values at 4:00 p.m. and midnight. Hourly sampling of plasma cortisol over 24 hr confirmed this rhythm, as did measurement of urinary free cortisols in samples collected every 6 hr over 24 hr. Hypercortisolemia was not suppressed by 2 mg of dexamethasone given every 6 hr for 24 hr. The adrenal tissue was responsive to ACTH. Iodocholesterol scanning revealed unilateral activity, and the patient's syndrome was cured by resection of an adrenal adenoma. In this patient a diurnal cortisol secretory pattern was present due to the secretory activity of the adenoma. The cause of the abnormal but persistent diurnal pattern is unknown.

17-Hydroxycorticosteroids↗
PubMed1978

Fear of success-fact or artifact?

Each of 240 high school juniors and seniors wrote stories in response to one of four variations of the story cues used by Matina Horner to measure what has been called "fear of success." These cues described either Ann or John achieving success in medical school in a situation in which either all of the protagonist's classmates were men or there were equal numbers of men and women. Six different consequences of the success were assessed. Results indicated that male and female students perceived the depicted success in similar ways and that when the "deviance" aspect of Ann being alone in a class of men was removed, negative outcomes of success were lessened. The common interpretation of these stories as the writers' projections of their own personalities is challenged.

Achievement↗
PubMed1977

Adult nephroblastoma.

A case of adult nephroblastoma in a 51-year-old woman is reported. A percutaneous aspiration biopsy did not lead to the right diagnosis presumably because the histologic structure of the tumour consisted exclusively of more or less differentiated epithelial-like elements, while mesenchymal tumour components were not demonstrated. It is concluded that this type of nephroblastoma, resembling a renal adenocarcinoma, should be borne in mind with a view to an optimal postoperative treatment.

Female↗
PubMedDate not supplied

Analysis of 31P MR spectroscopy data using artificial neural networks for longitudinal evaluation of muscle diseases: dermatomyositis.

Classical myopathic dermatomyositis (DM) is a chronic autoimmune disease characterized by an erythematous rash and severe, proximal muscle weakness. A disease variant, amyopathic DM, presents with the typical rash but without clinical evidence of muscle weakness. Prednisone and immunosuppressive drugs alleviate symptoms in many patients. Accurate longitudinal evaluations of patients are important to limit serious side effects of these drugs, including osteoporosis, cataracts, and growth inhibition. Metabolic abnormalities detected with 31P magnetic resonance spectroscopy (MRS) provide the best quantitative data for evaluating these patients. With 31P MRS, the levels of inorganic phosphate (Pi), phosphocreatine (PCr), ATP, and phosphodiesters (PDE) were determined in the quadricep muscles of patients during rest and exercise. Artificial neural network (ANN) analyses of these data were previously used for accurate classification of patients with myopathic or amyopathic DM and normal controls. In the present investigation, an artificial neural network was employed for further analysis of the 31P metabolite levels in quantitative, longitudinal evaluations of the extent (percent) of clinical improvement or deterioration during treatment with prednisone and immunosuppressive drugs. The ANN results showed that adult patients in a severe myopathic state could improve with treatment to a clinical status of amyopathic DM. In contrast, severely weak juvenile patients in the myopathic state recovered to normal status. One juvenile patient did not improve and remained in the myopathic state. Additionally, a serious clinical relapse in an amyopathic patient was predicted with serial ANN analyses well in advance of the actual clinical event. These network analyses show potential utility for clinical applications in muscle diseases.

Adolescent↗