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Biomedical subjects

J Howard

Publications and source records attributed to J Howard.

At least 19 recordsLinked to original sources

Fibronectin staining detects micro-organisms in aged and Alzheimer's disease brain.

Filamentous, fibronectin-immunopositive structures, previously described in Alzheimer's disease and control brains were negative for neuronal, glial, and macrophage markers. The present study sought to determine the nature of these entities and to further characterize their morphology, immunoreactivity and distribution between neuropathologies. Ultrastructural analysis shows these formations to be filamentous micro-organisms, which may belong to the actinomycetes. Immunohistochemistry for the cell-stress protein ubiquitin is consistently positive in these organisms. They are also present in Down's syndrome, dementia pugilistica, amyotrophic lateral sclerosis with dementia, and Parkinson's disease. The pattern of tissue distribution implies a pre-mortem invasion of the brain, and, as the micro-organism is present at a four to five-fold higher frequency in Alzheimer's disease, it may act pathogenically in this dementing illness.

Actinomyces

Prospects for humane care are hopeful.

Token deference to humanism will not get the job done/The goal of humanizing care must be given high priority and be made consistent with other hospital objectives.

Hospital Administration

A biochemical and ultrastructural comparison of Triton X-100 models of normal and transformed cells.

We have compared the two-dimensional gel profiles of Triton models of normal rat kidney (NRK) cells and their Kirsten viral transformant, 442. Several protein differences were detected. The models of the transformed line lacked five acidic polypeptides and possessed a much higher intermediate filament to actin ratio. Scanning microscopy reveals significant ultrastructural differences in these models, with the NRK line exhibiting a much more filamentous structure. In addition, nuclease treatment of NRK models causes a dramatic change in their scanning image while the 442 models are unaffected. Nuclease treated models lack microfilaments and appear to contain only intermediate filaments, although actin is still a prominent protein constituent.

Actins

Comparison of heavy particle with X-irradiation on the hamster lung.

Important new modalities for cancer therapy are being developed, and one of the most promising is heavy charged particle irradiation. We are currently assessing the effects of 375-MeV/nucleon neon irradiation in the plateau region of ionization compared to 230KVp X-rays on the whole thorax of hamsters. Single dose levels for neon irradiation ranged from 150-1000 rad. Dose levels for X-irradiation ranged from 225-1500 rad. The animals were followed for 1 year after irradiation, and the most useful results emerged, using morphometric methods. One year after irradiation, pulmonary parenchyma and nonparenchyma appear morphometrically unchanged. However, the volume density of pulmonary septums, septal cells, all tissue, connective tissue, and alveolar Type II cells was increased while the volume densities of alveoli, empty alveolar space, and capillary lumens were diminished. Most of these changes were dose dependent not clearly demonstrable until a year after irradiation. The relative biologic effect of neon compared to X-irradiation using this techniques is 1.6-1.8.

Animals

Fitness and employee productivity.

What should management consider when deciding whether to sponsor a company fitness program? This article gives pragmatic answers to the business community as well as outlining critical avenues for future research for both academics and corporations. Understanding the nature of the commitment is a prerequisite for success. Whether the program should be short term and serve as a catalyst for future individual efforts, or a long-term commitment, is a question which must be considered. Decisions of this type are partially dependent on what criteria are used to evaluate success. As measurements of employee productivity are very subjective or non-existent, absenteeism and turnover are potential yardsticks. Details of employee programs must also address the issue of participation as well as the frequency, intensity and duration. Future research must separate the effect of the fitness improvement from the benfits derived from just being in a program. The measurement of productivity and the long-term effect of fitness programs, especially short-term programs, are also areas for future work.

Attitude

A heavy particle comparative study. Part I: depth-dose distributions.

The results of a comparative study of heavy particles of interest in radiotherapy, with peaks spread over a depth of 10 cm, are reported in four parts. The introduction to this study and the depth-dose distributions of the particles, (n, pi-, p, He, C, Ne, and Ar ions) are reported herein. The results indicate that protons give the best localization of dose. The degree of localization of dose with heavy ions is reduced with increasing charge on the ion. For ranges less than 15cm, heavier ions such as neon and argon still have favourable dose localization; however, for ranges in excess of 15 cm, heavy ions such as argon are unfavourable but superior to fast neutrons because penetration can be controlled by modulation of energy or range.

Argon

A 45,XX,-5,-14,+t(5q;14q)mat cri du chat child.

A two-year-old girl has the following features of the cri du chat syndrome: microcephaly, hypertelorism, downward slanting of the palpebral fissures, psychomotor retardation and a cat-like cry. She is only of five patients having the cat cry syndrome with 45 chromosomes. Her karyotype is 45,XX, -5, -14, +t(5; 14)(5qter leads to 5p11: : 14q11 leads to 14qter) with the translocation inherited from her mother and maternal grandmother, each of whom is the carrier of a balanced translocation 46,XX,t(5;14)(p11q11). Normal plasma activity for hexosaminidase B suggests the locus for this enzyme is not located in the delected segment of 5 p.

Chromosome Deletion

cis-Dichlorodiammineplatinum(II) and bleomycin in the treatment of esophageal carcinomas.

Forty-seven patients with squamous cell carcinoma of the esophagus were treated with a combination of cis-dichlorodiammineplatinum (II) (cis-DDP) and bleomycin by infusion. cis-DDP at a dose of 3 mg/kg with mannitol and prehydration was given on Day 1. On Day 3, bleomycin was started as a 10--15-unit/m2 loading dose followed by a 10--15-unit/m2 24-hour infusion for 4--7 days. Three groups of patients were treated: group 1 (no clinical evidence of metastatic disease) included 25 patients, all with no prior therapy; group 2 (measurable metastatic disease) included 13 patients, eight previously treated with surgery and/or radiation; group 3 (known nonmeasurable metastatic disease) included nine patients, all previously treated with surgery and/or radiation and/or chemotherapy. A second course of therapy was given on Day 28 to groups 2 and 3, and as soon after surgery as possible in group 1. Nineteen percent of patients had complete or partial responses with another 44% having minor regressions. Toxic effects were mainly renal effects, alopecia, nausea and vomiting, and stomatitis. There were two drug-related deaths. The combination of cis-DDP and bleomycin is useful in the treatment of patients with squamous cell carcinoma of the esophagus.

Adult

Stress reactions in organizations: syndromes, causes and consequences.

This study examines the prevalence, causes, and consequences of stress reactions among over 2000 high status members of a large organization in Canada. Five stress syndromes were identified: emotional distress, medication use, cardiovascular disturbance, gastrointestinal disturbance, and allergy respiratory disturbance. The study demonstrates the effects of sociocultural variables on selected stress responses to compare typical symptoms of French vs. English Canadians, and in demographic variables such as age and sex as reflections of stages in the life cycle. Once the sociocultural and demographic effects were isolated, the study revealed a major occupational effect in the distribution of stress syndromes. Managers compared with staff and operations people show a low prevalence of stress reactions. The explanation of this finding led to the evaluation of four possible causes: the maturity effect, the vulnerability effect, the bureaucratic effect, and the power effect. The first two causes assume the objective stressors in the environment are about the same for all occupational groups in the study and the variations in symptoms result from major personality factors held in common among the occupational groups. The second two causes assume that the variations in symptoms result from major differences in the environments of the three occupational groups. Analysis suggests that psychodynamic factors affect the tolerance for stress and the choice of syndrome. The environment, particularly the frustrations and deprivations associated with bureaucracy and the lack of power, activates the defenses against anger and rage that in turn lead to symptom formation. The study concludes with the paradox of the bureaucratic experience. Designed to minimize the uses of power in negotiating work procedures and relationships, bureaucracy requires the mobilization and uses of power to, at a minimum, reduce the risks of falling ill from frustration and anger and, at a maximum, to sense one's impact on events.

Adult