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R Hartman

Publications and source records attributed to R Hartman.

11 recordsLinked to original sources

Relationship of F-actin distribution to development of polar shape in human polymorphonuclear neutrophils.

Polymerization of actin has been associated with development of polar shape in human neutrophils (PMN). To examine the relation of filamentous actin (F-actin) distribution to shape change in PMN, we developed a method using computerized video image analysis and fluorescence microscopy to quantify distribution of F-actin in single cells. PMN were labeled with fluorescent probe NBD-phallicidin to measure filamentous actin and Texas red to assess cell thickness. We show that Texas red fluorescence is a reasonable measure of cell thickness and that correction of the NBD-phallicidin image for cell thickness using the Texas red image permits assessment of focal F-actin content. Parameters were derived that quantify total F-actin content, movement of F-actin away from the center of the cell, asymmetry of F-actin distribution, and change from round to polar shape. The sequence of change in F-actin distribution and its relation to development of polar shape in PMN was determined using these parameters. After stimulation with chemotactic peptide at 25 degrees C, F-actin polymerized first at the rim of the PMN. This was followed by development of asymmetry of F-actin distribution and change to polar shape. The dominant pseudopod developed first in the region of lower F-actin concentration followed later by polymerization of actin in the end of the developed pseudopod. Asymmetric F-actin distribution was detected in round PMN before development of polar shape. Based upon these data, asymmetric distribution of F-actin is coincident with and probably precedes development of polar shape in PMN stimulated in suspension by chemotactic peptide.

Actin Cytoskeleton

Reduced risk of NSAID gastropathy (GI mucosal toxicity) with nonacetylated salicylate (salsalate): an endoscopic study.

This randomized, investigator-blinded, parallel group endoscopic study evaluated the effects of salsalate and naproxen on the gastroduodenal mucosa over a 3-month period in patients with RA. Using therapeutic doses of the drugs, 8 of 21 patients (38%) in the naproxen group had endoscopically shown active ulcers (seven patients) or diffuse erosions (one patient), whereas none of the 18 patients treated with salsalate (0%) had such lesions (P = .003). Five of the eight naproxen-treated patients with evidence of GI damage were asymptomatic at the time of endoscopic verification of their lesions. The most significant disadvantage of salsalate was its higher incidence of otologic problems accounting for six of the nine discontinuations with salsalate. However, the findings of this study suggest that patients receiving salsalate are at lower risk for developing significant gastropathy than those treated with naproxen. The relative benefit-to-risk ratio of salsalate indicates that this drug should be considered as a significant alternative NSAID therapy.

Adolescent

Long-term survival following bony metastases from basal cell carcinoma. Report of a case.

A patient with recurrent basal cell carcinoma developed cervical-vertebral and epidural metastases. He received palliative irradiation and had a durable remission for three years. With relapse, he underwent a laminectomy and chemotherapy and remained asymptomatic at 54 months following the diagnosis of bony metastases. To our knowledge, he is the longest reported survivor with bony metastases and is illustrative of the potential survival advantage from palliative therapy.

Basal Cell Carcinoma

Avermectins, new family of potent anthelmintic agents: producing organism and fermentation.

The avermectins are a complex of chemically related agents which exhibit extraordinarily potent anthelmintic activity. They are produced by a novel species of actinomycete, NRRL 8165, which we have named Streptomyces avermitilis. The morphological and cultural characteristics which differentiate the producing organism from other species are described. The avermectins have been identified as a series of macrocyclic lactone derivatives which, in contrast to the macrolide or polyene antibiotics, lack significant antibacterial or antifungal activity. The avermectin complex is fully active against the gastrointestinal nematode Nematospiroides dubius when fed to infected mice for 6 days at 0.0002% of the diet. Fermentation development, including medium modification and strain selection, resulted in increasing the broth yields from 9 to 500 mug/ml.

Anthelmintics

Rape.

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Adolescent

Inversion lateral ankle trauma: differential diagnosis, review of the literature, and prospective study.

This study is comprised of 71 patients with inversion injuries. The purpose of this article is to present a logical and orderly approach in evaluating these injuries. A comprehensive review of the literature concerning diagnostic techniques and mechanisms of injury related to inversion ankle trauma is presented. Inversion ankle injuries are frequently misdiagnosed as simple sprains when frequently there are other pathologies present. The standard approach of evaluating inversion ankle injuries is often inadequate.

Ankle Injuries