Search PubMed⌕ Search

Biomedical subjects

J C Ziegler

Publications and source records attributed to J C Ziegler.

23 records · Page 2Linked to original sources
PubMed1992

Implementation of a national nursing standards program.

At an annual nursing management conference of a multisystem hospital management firm, nursing executives expressed a need for developing nursing care standards. Because many of the hospitals were small or rural, they lacked some of the resources needed to develop such a program individually. Pooling resources so that all could benefit was an innovative and sensible approach. The authors describe the project that resulted in the development of a nation-wide standards program involving nearly 50 hospitals.

Models, Organizational↗
PubMed1991

Immobilization of microsomes into alginate beads is a convenient method for producing glucuronides from drugs.

The production of glucuronides from drugs by immobilized microsomal uridine diphosphate (UDP)-glucuronosyltransferase has been investigated. Of all the immobilization methods used (covalent binding, adsorption by ionic or hydrophobic interactions), only entrapment of microsomes into alginate beads in the presence of polyethyleneimine was effective in producing high glucuronidation rates, thus leading to the formation of large amounts of metabolites. The performance of the bioreactor was optimized with the drug 3'-azido-3'-deoxythymidine (AZT), active against the human immunodeficiency virus, as a model substrate of UDP-glucuronosyltransferase. Calcium (12 mM) could optimally improve the stability of microsomes entrapped in alginate beads. Upon immobilization, enzyme activation occurred, leading to a fivefold increase in specific activity. The determination of apparent Km and Vmax revealed that AZT was a better substrate for the immobilized enzyme than free microsomes. The AZT-glucuronide production obtained after 6 h was threefold higher than that observed with free microsomes. This bioreactor was also efficient in production of glucuronides from structurally different compounds such as bilirubin, 4-nitrophenol, clofibric acid, pirprofen, dextrorphan or morphine, the corresponding glucuronide of which possesses pharmacological or toxicological interest.

Alginates↗
PubMed1991

External beam irradiation versus 125 iodine implant in the definitive treatment of prostate carcinoma.

We reviewed the record of all 983 patients seen at the Hahnemann University, Department of Radiation Oncology for evaluation of prostate cancer during the megavoltage era. We compared the results of 276 patients who were treated definitively with either external beam irradiation or Iodine 125 implantation. The groups were similar in most prognostic characteristics. Where appropriate, multivariate statistical techniques were used to compensate for the effects of differences in grade and stage between the two groups. There were striking differences between implant and external beam patients in both local failure rates and disease-free survival, mostly attributable to poor local control in the implant patients. Thirty-eight percent of the Stage A and B implant patients failed locally in the first 5 years whereas only 5% of a comparable group of external beam patients did so. A2 patients, however, exhibited similar disease-free survival in both cohorts. Complication rates were 11% in the implant group and 19% in the external beam group. We conclude that there are serious doubts about the efficacy of Iodine 125 implantation in maintaining local control, and that this translates into worse relapse-free survival. By contrast, local control and relapse-free survival may be satisfactory in the A2 patients, and complication rates may be lower with implant. The above suggests that Iodine 125 interstitial implantation is well suited to only a minority of early stage prostate cancer patients and that most patients with Stage B and C prostatic carcinoma should be treated with either external beam irradiation or with radical prostatectomy.

Aged↗
PubMed1986

Brain metastases from malignant melanoma: conventional vs. high-dose-per-fraction radiotherapy.

This report examines the records of 72 patients who received various regimens of radiotherapy for cerebral metastases from malignant melanoma at NYU Medical Center. Treatment consisted of whole-brain irradiation, either with dose fractions of 300 cGy (conventional fractionation, CF) or 500-600 cGy (high-dose-per-fraction, HDF) to a total of 3000 cGy. Two-thirds of the patients responded to radiotherapy as measured by improvement of at least one functional level. No difference in response could be attributed to dose schedules, either overall or in the subgroups of patients who had solitary or multiple brain metastases. Median survival was not significantly affected by fractionation schedule; however, patients who had solitary metastases survived longer, probably because of the nature of their disease. Treatment related toxicity was more frequent in the HDF group. The subgroup of patients who had their only clinically demonstrable lesion grossly excised prior to treatment survived more than twice as long as other patients. We conclude that radiotherapy is effective in palliating symptoms for these patients. Our data does not support the use of HDF techniques in the treatment of patients with brain metastases from malignant melanoma.

Brain Neoplasms↗