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Biomedical subjects

I Kaplan

Publications and source records attributed to I Kaplan.

At least 91 records · Page 5Linked to original sources

Microleakage of composite resin and glass ionomer cement restorations in retentive and nonretentive cervical cavity preparations.

Ketac Fil glass ionomer cement (GIC) and Scotchbond 2 dentinal bonding agent (DBA)/Silux Plus composite resin restorations were inserted in cervical cavity preparations of extracted human teeth. After thermocycling, the specimens were invested and sectioned longitudinally and horizontally through the center of the restoration. Microleakage was evaluated as a ratio of the extent of methylene blue dye penetration at the tooth-restoration interface. Although all restorations exhibited leakage, both the GIC and bonded composite resin restorations recorded less leakage in retentive than in nonretentive cavity preparations. Composite resin restorations in nonretentive cavity preparations showed significantly more dye penetration toward the pulpal chamber than the GIC restorations. Ketac Fil GIC restorations inserted without a matrix strip exhibited less leakage than those with a matrix strip. The most desirable results were recorded with Scotchbond 2 DBA/Silux Plus composite resin restorations in retentive preparations.

Acid Etching, Dental↗

The clinical significance of a positive post-irradiation prostatic biopsy without metastases.

To define the prognostic value of a post-irradiation prostatic biopsy, the outcome of 203 previously irradiated patients who underwent post-treatment biopsy was analyzed. The majority of patients were selected for biopsy based on an abnormal digital rectal exam or elevated prostate specific antigen. Patients with distant metastases found at the time of biopsy were excluded from further analysis. One hundred thirty-nine (139) of these had a positive biopsy and 64 were negative. Those with a positive biopsy tended to present with more locally-advanced (Stage B2/C) tumors (61%) compared to those with negative biopsies (42%). The 10- and 15-year survival and cause-specific survival from the time of initial presentation were similar for both groups. However, those with a negative biopsy had a more favorable survival and cause-specific survival from the time of post-treatment biopsy and were less likely to develop distant metastases than the positive biopsy group. These data suggest that a positive prostatic biopsy is associated with a greater likelihood of subsequent distant relapse and decreased survival following biopsy relative to patients with negative biopsies. Since a positive post-treatment biopsy is more likely among patients presenting with locally-advanced disease, perhaps more aggressive initial therapy (i.e., interstitial boost or hyperthermia) would benefit this subgroup.

Adenocarcinoma↗

Experimental surgery on dog's stomach and liver using CO 2 laser plastic hollow fibers: technical method.

Plastic hollow fibers for the transmission of CO 2 laser energy in curved paths were produced by plating the inner surface of plastic tubes with a metal film and dielectric film upon it. These fibers can transmit high power up to 40 W at the outlet, with high transmission yield even through several bendings. A three-dimensional simulator was built to simulate paths in the dog's body and the outlet power was measured. From the achieved data the expected transmitted power during real surgery was appreciated. The fibers were checked for their influence on live tissues of dogs. Incisions were made in the liver and ulcers in the dogs' stomachs were treated. The fibers were inserted into the stomach through the dogs' esophagus. Complete healing was observed after four weeks.

Animals↗

The use of the CO 2 laser in oral surgery in the military.

From 1987 to 1990, there were 122 soldiers treated with the CO 2 laser (Sharplan 1010) in the Laser Center of the Israel Defense Forces. A variety of benign oral lesions, vascular tumors, and other oral lesions were excised or vaporized. Twenty-four soldiers with impacted wisdom teeth and wide pericoronitis underwent operculectomy using the CO 2 laser. The CO 2 laser has the ability to perform accurate hemostasis surgery, with minimal postoperative pain and edema, and rapid healing, resulting in fast recovery without significant discomfort. These advantages are particularly important in the military since soldiers can return to their duties immediately after surgery.

Adolescent↗

CO 2 laser used in surgical treatment of actinic cheilitis.

This study discusses the satisfactory CO 2 laser treatment of solar keratosis on Eastern European emigrants to Israel. It offers a comparison between cold blade vermilionectomy based on previous data and experience and reports postoperative results concerning cosmetic appearance and function of the lip.

Cheilitis↗

Stereotactic radiosurgical treatment of brain metastases.

In a series of 33 patients with reasonably controlled primary cancers, stereotactic radiosurgery was used to treat 52 brain metastases. After a mean radiological follow-up time of 5.5 months, six lesions (12%) had stabilized in size, 26 (50%) were significantly reduced, and 15 (29%) had disappeared. One large melanoma metastasis progressed relentlessly despite treatment. Five lesions (9%) had decreased in size slightly before enlarging. In two of these lesions, biopsy revealed only necrosis. In almost all cases, treatment was associated with decreased peritumoral edema. However, a group of patients with large metastases and extensive prior brain irradiation has been identified in whom prolonged symptomatic cerebral edema poses a problem. It is concluded that radiosurgery is a viable alternative to surgical resection for some cases of brain metastasis.

Adult↗

Secondary external-beam radiotherapy and hyperthermia for local recurrence after 125-iodine implantation in adenocarcinoma of the prostate.

At Stanford, six patients underwent a course of external radiotherapy after local recurrence following 125-iodine implantation. Four of the six patients also received concomitant hyperthermia. Four patients were initially managed with hormonal manipulation at time of local relapse and subsequently received external beam radiotherapy with or without hyperthermia. The hyperthermia was non-invasively induced using an annular phased array radiative electromagnetic system. Treatment was well tolerated, and none of the patients experienced severe rectal or bladder complications. Three patients are free from disease; one patient experience local-regional recurrence based on biopsy; one recurred in the bladder, was treated with cystoprostatectomy and subsequently succumbed to metastatic disease; and one patient died of presumed metastatic disease. External-beam irradiation with concurrent hyperthermia can be safely delivered to treat locally recurrent prostatic carcinoma after 125-iodine implantation.

Adenocarcinoma↗

Preliminary experiments of possible uses in medicine of novel plastic hollow fibers for transmission of CO2 radiation.

Plastic hollow fibers for the transmission of CO2 laser energy in curved paths were produced by plating the inner surface of plastic tubes with a metal film and dielectric film upon that. These fibers can transmit high power, up to 40 W at the outlet, with high transmission yield even through several bendings. To demonstrate a possible use of the fibers, they were checked for their influence on live tissues of dogs. Incisions were made in the liver, and ulcers in the dogs' stomachs were treated. The fibers were inserted into the stomach through the esophagus. Complete healing was observed after 4 weeks.

Animals↗

Prostate specific antigen after irradiation for prostatic carcinoma.

The clinical significance of serum prostate specific antigen after primary irradiation for adenocarcinoma of the prostate is uncertain. Between September 1986 and December 1987 serial prostate specific antigen values were determined in 43 patients before and after definitive radiation therapy. The study group included 6 patients with stage T0d, 10 with stage T1, 11 with stage T2 and 16 with stage T3 disease, with a mean pre-treatment prostate specific antigen level of 49.2 +/- 10.8. For all patients the first post-treatment prostate specific antigen level was less than the pre-treatment level. One patient failed locally with recurrent prostatic cancer that invaded the rectum. The 6 patients who failed with symptomatic metastases had an increasing prostate specific antigen level 2 to 7 months before detection of recurrence. Based on the absolute value and trend of the prostate specific antigen, patients were described as being at high, intermediate or low risk for distant metastases. Of 9 high, 6 intermediate and 28 low risk patients 4 (44%), 2 (33%) and 0 (0%) have experienced recurrent disease (p = 0.0025). We conclude that serial post-irradiation prostate specific antigen values may be useful in the early identification of patients at risk for treatment failure.

Adenocarcinoma↗

Steroids induce acetylcholine receptors on cultured human muscle: implications for myasthenia gravis.

Antibodies to the acetylcholine receptor (AChR), which are diagnostic of the human autoimmune disease myasthenia gravis, block AChR function and increase the rate of AChR degradation leading to impaired neuromuscular transmission. Steroids are frequently used to alleviate symptoms of muscle fatigue and weakness in patients with myasthenia gravis because of their well-documented immunosuppressive effects. We show here that the steroid dexamethasone significantly increases total surface AChRs on cultured human muscle exposed to myasthenia gravis sera. Our results suggest that the clinical improvement observed in myasthenic patients treated with steroids is due not only to an effect on the immune system but also to a direct effect on muscle. We propose that the identification and development of pharmacologic agents that augment receptors and other proteins that are reduced by human genetic or autoimmune disease will have broad therapeutic applications.

Autoantibodies↗

The use of the CO 2 laser in oral and maxillofacial surgery.

The CO 2 laser has a decided advantage in removing tumors of the oral cavity. This advantage is related to its ability to perform accurate hemostatic surgery, while at the same time sterilizing the operative area. During the past 4 years, 376 patients have been treated with the CO 2 laser (Sharplan 1040) at our hospital. A variety of benign oral lesions, malignant tumors, vascular tumors, preprosthetic surgery, and other oral lesions have been treated.

Humans↗