How to handle a strike.
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Biomedical subjects
Publications and source records attributed to C Anderson.
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Ribs from 6 oophorectomized and 4 17 beta-estradiol-supplemented spayed, 4-year-old Beagle dams were subjected to histomorphometric analyses to determine what effects continuous estradiol treatment of 9 months duration had on the Basic Multicellular Unit (BMU) of cortical bone remodeling. The findings of this study suggest that 17 beta-estradiol has a two-step mode of action. First, this estrogen directly suppresses the formation of new BMUs. Secondly, it causes uncoupling of the Resorption/Formation (R/F) mechanism within each BMU, together with the creation of an approximate 1:1 balance between bone resorption and bone formation. This balance is probably responsible for the preservation of cortical bone mass seen to occur with continuous estrogen replacement therapy.
Cortical bone remodeling measurements were carried out on the ribs of 6 spayed and 5 progestogen-treated spayed Beagle dams which had been subjected to a period of observation equal to more than 1 sigma of intact canine bone remodeling activity. Analyses of static and dynamic features indicated that continuous medroxyprogesterone acetate replacement therapy altered the rates of cortical bone remodeling activity. In the progestogen-treated dams, more Basic Multicellular Units (BMUs) were activated, exhibiting shortened resorption and formation times. Thus, this progestogen appears to play a significant role in regulating cortical bone cell activity and, as such, suggests that progesterone may play a part in the prevention or slowing down of cortical bone loss in females following menopause or oophorectomy.
Resorptive and formative characteristics of the periosteal and corticoendosteal envelopes of the ribs of intact and spayed Beagle dams were studied. Six 4-year-old Beagle dams were spayed at source and kept under observation for 12 months. Four intact age- and weight-matched Beagle dams were used as controls. Before euthanizing, all dams received tetracycline labeling of their bones. Histomorphometric analyses of resorptive and formative parameters of the periosteal and corticoendosteal envelopes were carried out blind. The results indicated that following oophorectomy, there is an increase in resorptive surfaces on the periosteum and corticoendosteum, and a decline of formative activity on these same envelopes. These changes were manifested to a greater extent on the corticoendosteum. The lack of ovarian hormones contributes to an increase in the mineralization lag-time on the periosteum. Although in both control and spayed dams a similar pattern of surface activity was observed on both envelopes investigated, the differences in degree may be attributable to the ovarian hormone withdrawal.
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In the early premature, the EEG is mostly discontinuous. Discontinuity becomes limited to quiet sleep periods by the 36th week of conceptional age (CA). Temporal theta bursts, or the "sawtooth" pattern, come and go between 27 and 32 weeks' CA. Delta brushes attain their maximum about 32 to 34 weeks' CA and disappear about 40 to 44 weeks' CA. Frontal sharp transients have their peak occurrence at 35 or 36 weeks' CA and are still present at 44 to 48 weeks' CA. The background activity is essentially symmetric but transient patterns are less symmetric and frequently asynchronous. Lack of variability in the record is abnormal after 34 weeks' CA. Responses to isolated light flashes are prominent from very early prematurity through full-term. On the other hand, photic driving is frequent in early prematures (29-32 weeks' CA), but it then declines and is difficult to detect in the full-term neonate. Nonspecific responses to stimulation occur from early prematurity. Sleep--waking cycles are clearly discernible about 37 weeks' CA. Active sleep (rapid eye movement) goes from 60% at 34 weeks' CA to the 25% of adulthood at about 8 months of age. The EEG of the full-term newborn has four patterns, corresponding to three states: the low voltage irregular for wakefulness, high voltage slow and tracé alternant for quiet sleep, and the mixed for either wakefulness or active sleep.
Two major components of human brain S100 fraction were purified by HPLC and an amino acid sequence was elucidated for the S100 beta component. Human S100 proteins showed absorption spectra and amino acid compositions similar to S100 alpha and S100 beta from bovine brain. However, the relative amounts of the human proteins were 4% S100 alpha and 96% S100 beta by weight, while the bovine protein distribution was 47% S100 alpha and 53% S100 beta by weight. An amino acid sequence of human S100 beta was established by analysis of overlapping fragments generated by cyanogen bromide and trypsin cleavage. Three amino acid sequence differences between the human and bovine S100 beta were found at residues 7, 62, and 80. These differences were chemically conservative and compatible with minimum single base changes in the codon structures. These results document that S100 beta is a conserved protein among mammals and provide the necessary foundation for current clinical studies.
In a study of the effects of cyclosporin A on the allergic contact reaction to oxazolone in the guinea pig, a pronounced ability to suppress redness and edema and the dermal inflammatory cell infiltrate was demonstrated. At the generally recommended (human) organ transplantation immunosuppression dosage (20 mg/kg), a single dose gave no certain effect, but when repeated daily for 3 days, some suppression of the reaction was seen. A single 80 mg/kg dose produced marked suppression of erythema and edema and all components of the dermal cellular infiltrate. This effect was still evident, though less marked, 3 days after administration. The 80 mg/kg dose had no effect on the toxic contact reaction to croton oil. Of the agents we have previously tested (cyclophosphamide, methotrexate and azathioprine) with this model, cyclosporin A has by far the most marked capacity to suppress the allergic (cell-mediated) contact reaction, via a mechanism which would appear to involve immunomodulation rather than mere nonspecific anti-inflammatory effects.
Cyclophosphamide is a cytostatic agent used clinically and in experimental studies for its immunosuppressant effect. Effects on the afferent and efferent limb of the contact allergic reaction have been shown. The substance has also non-specific, anti-inflammatory effects and these were investigated in this paper by studying the effects of single doses of cyclophosphamide on the toxic contact reaction to croton oil (a non-specific inflammatory reaction) in guinea pig. Counting of the dermal cellular infiltrate showed that mononuclear and granulocyte counts decreased in a dose-dependent fashion after cyclophosphamide administration. Erythema and oedema in the test reactions decreased generally, although at the highest dose a paradoxical increase was seen.
Single intraperitoneal injections of cyclophosphamide were administered 6 days before testing guinea pigs sensitized to oxazolone in order to study the effects on inflammatory cell populations in blood and dermis. Skin tests were assessed macroscopically (erythema and oedema) and microscopically (counting of the dermal inflammatory cell infiltrate). At the highest dose (300 mg/kg) the allergic contact reaction was augmented with increases in erythema and oedema and the mononuclear dermal infiltrate. At the lowest dose (75 mg/kg), redness and oedema and all components of the dermal inflammatory cell infiltrate decreased. Total and differential white blood counts up to 20 days after administration of cyclophosphamide showed that a dose-dependent leukopenia maximal around 6 days occurred. During the leukopenia the differential count showed a lymphocytosis with a marked granulocyte depletion. The augmentation of the contact allergic reaction produced at the highest dose of cyclophosphamide occurs despite a marked peripheral blood leukopenia. Cyclophosphamide's effects at the lower dose would appear to be of a non-specific anti-inflammatory nature.
The present study collected the first normative data on a new dynamic isokinetic lifting device and compared a normal subject sample (n = 65) with a chronic low-back pain patient sample (n = 68) on this device. In addition, a comparison was made between isometric lifting measures collected for these controls and patients, and a normative industrial sample used in an earlier isometric testing protocol. Results demonstrated significant differences between controls and patients on all measures. An unanticipated finding was the greater lifting capacity levels of the present normal sample relative to those reported in the earlier isometric testing. These findings demonstrate that dynamic lifting simulation offers an important new tool for medical and industrial assessment, and conservative medical management.
A guinea pig experimental model which allows comparison of the macroscopic appearance of skin tests with the nature and degree of the dermal inflammatory cell infiltrate has been used to study the effects of cyclophosphamide, methotrexate, azathioprine and cyclosporin A on contact reactions. The immunomodulating capabilities of the agents tested are assessed by their effects on the allergic contact reaction to oxazolone, a cell-mediated delayed hypersensitivity reaction. Non-specific, anti-inflammatory actions are assessed by effects on the toxic contact reaction to croton oil. Changes are compared to findings in reference animals for each reaction. The reference materials and the uses and limitations of the experimental model are evaluated. When administered prior to sensitization, all agents enhanced the macroscopic appearance of the allergic contact reactions. Changes in the dermal cellular infiltrates were not pronounced. When administered prior to testing, cyclophosphamide, methotrexate and azathioprine caused changes compared to controls which varied in direction and degree both macroscopically and microscopically. Cyclophosphamide which was the most active agent showed non-specific, anti-inflammatory effects and caused a peripheral blood leukopenia, the level and character of which was essentially independent of the dermal cellular infiltrate of tests. Cyclosporin A demonstrated no non-specific, anti-inflammatory activity on the toxic reaction, but had by far the most pronounced immunosuppressant effect of the agents tested, with virtual quenching of both the macroscopic appearance and all aspects of the dermal cellular infiltrates of the allergic contact reaction.
Dissociated cells of the marine sponge, Microciona prolifera, aggregate in response to a species-specific aggregation factor (MAF) and Ca ionophores. We now report that leukotriene B4, a 5-lipoxygenase product, also causes aggregation of sponge cells. No other lipoxygenase products provoked aggregation. However, nordihydroguaiaretic acid (NDGA), colchicine, indomethacin, piroxicam and ibuprofen inhibited MAF-induced aggregation; the latter three agents inhibited Ca movements. Inhibition of prostaglandin release cannot be the mechanism whereby these agents inhibit aggregation of sponge cells, since the cells do not respond to exogenous cyclooxygenase products.
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The stomach, small intestine and large intestine of the toad, Bufo marinus, were processed for formaldehyde-induced fluorescence histochemistry. After extrinsic denervation or pretreatment with 6-hydroxydopamine to remove catecholamine fluorescence, yellow fluorescence typical of 5-hydroxytryptamine was observed in neurones in the small intestine only. The cell bodies and their processes were confined to the myenteric plexus. Additional pretreatment with 5-hydroxytryptamine enhanced the fluorescence of neurones in the small intestine and revealed yellow-fluorescent nerve fibres, but not cell bodies, in the longitudinal and circular muscle layers and myenteric plexus of the large intestine. No fluorescent neurones were observed in the stomach. Following reserpine treatment, which removed native yellow fluorescence in the small intestine, exposure to 5-hydroxytryptophan produced yellow fluorescence in axons in both small and large intestine; exposure to tryptophan never restored fluorescence. The neurotoxin, 5,7-dihydroxytryptamine had no effect on the distribution of yellow-fluorescent neurones in the small and large intestine. No 5-HT-containing mast cells were present in either the small or large intestine. Thin layer chromatography with three different mobile phases showed a 5-hydroxytryptamine-like compound in extracts of mucosa-free small and large intestine but not of stomach.
Five patients suffering from osteoporosis were subjected to from three to eight cycles of a form of Coherence Therapy for Osteoporosis (1) used at this center. Assessment of the patients' trabecular bone remodeling activity as measured by histomorphometric analyses of trans-iliac crest bone biopsies showed a marked improvement.
Cortical bone remodeling measurements were carried out on the ribs of 6 spayed and five control Beagle dams which had been subjected to a period of observation equal to more than one sigma of cortical bone remodeling activity. The results of the measurements of static and dynamic parameters indicate that the lack of ovarian hormones does not produce a major alteration in the rates of cortical bone remodeling, but does result in an increase in the number of resorption spaces per mm2 of cortical bone without altering the parameters of bone function. This latter fact supports the hypothesis that decreased levels of circulatory ovarian hormones may influence the duration of the resorption activity as well as possibly uncoupling the resorption/formation (R/F) mechanism of the bone remodeling unit.
Preliminary findings regarding quality of life of 458 renal patients treated by in-center hemodialysis, continuous ambulatory peritoneal dialysis (CAPD), or transplantation indicate more favorable adjustment for CAPD patients when compared with center hemodialysis patients. Patients with a successful transplant show the highest overall adjustment when compared with both groups of dialysis patients.