Showing papers by "Rush University Medical Center published in 1976"

Biocompatibility of materials for total joint replacement

Abstract: The clinical use of total joint prostheses demands absolute biocompatibility of the materials employed. The purpose of this experiment was the bioassay of some materials considered as possible candidates for use in total joint prostheses as load-bearing members or as wear-resistant surfaces. Some materials already in use were also tested. 316L stainless steel was used as a control. The materials were implanted as a standardized rod and in particulate form. An average of 12 samples per material were implanted in soft tissue for six months and a total of 145 rabbits were used in this study. Twenty-five materials including metals, polymers, and ceramics were tested in solid and powdered form. A semiquantitative evaluation of local tissue reaction and a study of organs was performed. Polymers and metallic materials showed in general a mild tissue reaction. Ceramics, which some authors describe as the best tolerated materials, elicited variable tissue responses. Some of these (glass–ceramics) presented very poor tissue tolerance. The least reactive, titanium oxide, titanium aluminate, and aluminum oxide, presented a degree of tissue reaction comparable to that of corrosion resistant metals, but not superior to them. Moderate reactivity was the general rule for particulate materials except for the Pyroceram glass–ceramics, polyimides, and Teflon. Ultrahigh molecular weight polyethylene in particulate form elicited a rather cellular tissue response, a fact to be considered when projecting long-term results in total joint arthroplasty. No pathological changes compatible with systemic toxicity by materials tested were observed in the study of the organs.

Radiation therapy for osseous metastasis.

Abstract: Pain relief from osseous metastasis is readily achieved by local radiation therapy. Significant relief is predictable for about 9096 of the patients. This study demonstrates that a short course, low dose treatment schedule is highly effective. Ordinarily “resistant” tumors such as prostate carcinoma have a good ultimate response but may be slower in manifesting than for breast and lung cancer.

Bone marrow scanning with 52iron (52Fe). Regeneration and extension of marrow after ablative doses of radiotherapy.

Abstract: Extensively irradiated patients were studied from 0 to 73 months after irradiation by /sup 52/Fe bone marrow scanning. Marrow regeneration was observed in most patients after intervals of 12 months or longer. The degree of recovery was not dose-related and the marrow ablative dose was not defined with doses of 4000-5000 rads. Degree of recovery depended more upon the antomic region and/or sequence of fields treated; the last field treated invariably showed poorer regeneration when recovery was uneven. Active erythropoiesis expanded into distal inactive erythropoietic sites from 3 to 12 months after irradiation and then decreased thereafter. Blood count cytopenias were almost always restricted to the first year after irradiation.

Some new studies of the wear behavior of ultrahigh molecular weight polyethylene.

Abstract: The wear rate of ultrahigh molecular weight (UHMW) polyethylene over a long campaign of sliding distance is not constant. Both unfilled and graphite filled polyethylene show a high rate early, which reduces to a low value. The graphite-filled product shows a late stage increase in wear rate. Increased molding temperature reduces the molecular weight and increases the wear rate. Titanium articulating with UHMW polyethylene develops frequently an abnormally high wear rate with the generation of a black wear product.

Morphology of the GB hepatitis agent

Abstract: ATTEMPTS to isolate hepatitis A virus have been in progress for several decades. An important advance was the finding that the marmoset served as a permissive animal host for this virus1, but it became obvious that more than one agent was active. The pedigree of one agent was established as MS-1 (hepatitis A) isolate, while the other, which was demonstrably different by neutralisation and cross-challenge experiments, was designated GB. The GB infectious serum was obtained on the third day of jaundice from a surgeon in Chicago who developed a mild form of acute hepatitis. This serum induced hepatitis in all four marmosets inoculated. A pool of infectious GB serum marmoset (passage 11) was prepared from the total bleeding of nine white-lipped marmosets (Saguinus sp.) 19–24 d after inoculation and during the early acute phase of hepatitis as indicated by an increase of serum transaminase levels. This pool, designated H 205 GB pass 11, has an infectivity of 104.5 marmoset ID50. We have now examined the GB agent electron microscopically, and found that it is smaller and more fragile than the MS-1 strain2, and therefore also the identical CR326 isolate3 of hepatitis A, which have the morphological appearances of recognised, small cubic viruses measuring about 27 nm in diameter.

Changes in plasma membrane structure associated with malignant transformation in human urinary bladder epithelium.

Abstract: Integral membrane proteins are visualized as intramembrane particles (IMP; also called membrane-associated particles) at the cleaved surfaces of freeze-fractured plasma membranes. Topographical distributions of the IMP of urothelial cell membranes in normal human bladder and for a small series of low-grade noninvasive transitional cell carcinomas and invasive transtional cell carcinomas are shown to be significantly different. Using several statistical methods that test IMP topography via a vis the random (Poisson) hypothesis, it is demonstrated that IMP are mildly aggregated in plasma membranes of normal human urothelial cells and that, in noninvasive carcinomas, IMP aggregation is increased. In invasive transitional cell carcinomas, IMP are statistically nonaggregated and are in a random distribution in the plane of the membrane. IMP numerical densities are also altered in the course of neoplastic transformation. IMP are significantly increased in number in plasma membranes in human noninvasive transitional cell carcinomas but are similar to control values in invasive tumors. Loss of IMP and changes in IMP topography may be related to tumor invasiveness or they may represent an epiphenomenon.

Diazepam-ketamine anaesthesia for open heart surgery a "micro-mini" drip administration technique.

Abstract: Two hundred open-heart cases were anaesthetized with a diazepam-ketamine combination. The results were excellent. A “Micro-Mini” drip technique insured low, even, but adequate dose levels of ketamine and less drug was used. Induction and maintenance are simple and smooth. Effects on the cardiovascular system and respiratory system are minimal. The margin of safety is wide and 100 per cent oxygen can be used whenever needed.

A statistical treatment of fatigue of the cast Co-Cr-Mo prosthesis alloy.

Abstract: Fatigue tests have been conducted on commercially produced cast Co-Cr-Mo alloy in tension-tension while surrounded by a physiological solution at 37 degrees C. The data have been analyzed by statistical techniques to yield an allowable stress such that there is 95% confidence of less than one failure in 1,000 after 5 X 10(7) cycles of stress fluctuation. These results are valid for a substantially sounder material than may be common in commercial use and therefore a more conservative allowable stress probably ought to be used for design purposes.

Results of a randomized study comparing DTIC with TIC mustard in malignant melanoma

Abstract: This prospective randomized Eastern Cooperative Oncology Group (ECOG) study (1071) was designed to compare a new and promising cytotoxic agent TIC Mustard (triazeno imidazole carboxamide mustard, NSC 82196) with DTIC (dimethyl triazeno imidazole carboxamide, NSC 45388) in the treatment of inoperable melanoma. One hundred and seventy-eight patients were randomized to receive either DTIC (150 mg/m2/day X 5) or TIC Mustard (800 mg/m2/day X 5). Of this group 145 patients were evaluable for tumor response at the completion of the study. Objective responses were seen in 15/79 (19.0%) DTIC patients and 4/66 (6.1%) TIC Mustard patients. Adjustment of crude response rates yielded final response rates of 18.2% for DTIC patients and 5.8% for TIC Mustard. These differences were significant at the p less than or equal to .03 level. Median response duration was 15 weeks for the DTIC responders and 4 weeks for the TIC Mustard responders. Responders and nonresponders did not differ significantly in any of the standard prognostic categories. However, responders had a significantly longer median survival (47.5 weeks) compared to that for nonresponders (17.8 weeks). Toxicity was tolerable for either drug and no deaths were ascribed to either. We conclude that TIC Mustard has limited usefulness in the treatment of malignant melanoma and is less effective than DTIC.

Glycoproteins from mature human milk whey.

Abstract: Two milk-specific glycoprotein fractions and serum orosomucoid were isolated from mature human milk. One of the milk-specific glycoproteins was homogeneous and was termed glycoprotein A. Its sedimentation and diffusion constants were 2.6 S and 6.3 F, respectively, giving a molecular weight of 29,5000. It contained some 70% carbohydrate consisting of sialic acid, galactose, fucose, glucosamine, and galactosamine. It was not immunologically related to serum orosomucoid. The other glycoprotein, called glycoprotein B, was heterogeneous with an average molecular weight of near 4,000, and carbohydrate comprised some 75% of its weight. Both glycoprotein fractions supported the growth of Lactobacillus bifidus var. Penn. Removal of sialic acid enhanced the growth-promoting activity of glycoprotein B but not of A.

Malignant melanoma. Role of node dissection reappraised.

Abstract: Two hundred and fifty-nine patients with malignant melanoma have been reviewed. One hundred and fifty of these were determinate. A primary excision and dissection in continuity of the tumor, the intervening lymphatics, and the regional lymph nodes achieved a 5-year survival free of disease for 67.5% of the patients. When the nodes were clinically negative but microscopically positive, 45% survived. An elective discontinuous node dissection offers no better prognosis than does a therapeutic dissection and is not indicated in the primary treatment of malignant melanoma.

Physical education programs and exercise-induced asthma. Individualized gym programs allow asthmatic youngsters to participate with great benefit.

Abstract: THE NATIONAL HEALTH SURVEY (NHS), conducted in 1969-70, showed that asthma, with or without hay fever, was the third main cause of limitation of activity caused by chronic disease in persons under age 45.1 Further, asthma, with or without hay fever, resulted in limitation of activity in 30 per cent of persons under age 18 who have chronic respiratory tract disease.1 Later, in 1972, the Survey classified four types of limitations experienced by the school-age child: 1) no limitation on going to school, but restraint in participation of athletic or other extracurricular activities, 2) restrictions in school or school attendance, e.g., need special school, special training, cannot attend full time or for long periods at a time, 3) total inability to go to school, and 4) chronic mobility limitation.~ 2

Computed tomography of the abdomen: initial experience.

Abstract: Computed tomography has provided a new dimension in the roentgenologic evaluation of the abdomen. Normal structures not visible on conventional examinations are clearly identified. Abnormalities are recognized by their alterations in anatomic form or by their effect on tissue absorption values. Our early experience suggests that in the abdomen computed tomography will be most valuable in detecting lesions in those sites least accessible to conventional roentgenographic methods such as the liver, spleen, pancreas and retroperitoneum.

Stimulation of RNA and Protein Synthesis in Isolated Chondrocytes by Human Serum1

Abstract: The stimulation of isolated chicken embryo chondrocytes was studied by measuring the incorporation of [3H]uridine and [3H]leucine into cold trichloroacetic acid precipitable material after exposure of the chondrocytes to serum. The doseresponse relationships for the incorporation of uridine and leucine were similar to that of thymidine previously demonstrated. Exposure of the cells to serum-containing buffer for 15 min sufficed both for the stimulation of incorporation into the cells and for the depletion of 28% of the stimulating activity from the medium. Stimulation persisted for at least 17 h after removal of the serum. Studies whereactinomycin D was added to inhibit RNA synthesis suggested that prior RNA synthesis was required for most of the stimulation of protein synthesis by serum factors.

Stimulation of DNA Synthesis in Isolated Chondrocytes by Somatomedin. II. Validation of the Assay for Clinical Use and Comparison with the Stimulation of Protein Synthesis1

Abstract: The effects of GH on cartilage may be mediated by a variety of serum factors (somatomedins; SM). We have reported (Endocrinology 90: 1086, 1972) stimulation of thymidine incorporation in isolated chicken embryo chondrocytes by normal human serum. Thiswas greater than that caused by serum from patients with hypopituitarism. We have now compared the stimulatory activity estimated by [3H]thymidine incorporation (SMT) with that estimated by [3H]leucine incorporation in 46 sera from children with GH deficiency; with short stature, but normal GH responsiveness; or with normal stature and normal GH responsiveness. These activities were also measured in sera from 9 normal adults and 12 acromegalics. Sera from GH deficient children had reduced SMT activity (.54 ± 04; (mean ± SE) P < 01) compared to normal children (.83 ± 08), whereas the sera from children with short stature and normal GH responsiveness had higher levels than normal (1.19 ± 10; P < 02). Acromegalic adults averaged higher SMT activity than normal a...

Diverticulum of the female urethra. The value of the post-void bladder film during excretory urography.

Abstract: A simple technique utilizing the post-void film of the bladder during excretory urography is proposed for the diagnosis of female urethral diverticula. This technique provides for the diagnosis of this lesion in patients without clinical manifestations who would not normally undergo cystourethroscopy, retrograde urethrography, or voiding cystourethrography.