Search PubMed⌕ Search

Biomedical subjects

S M Pinsky

Publications and source records attributed to S M Pinsky.

At least 19 recordsLinked to original sources
PubMed2005

In vitro cytotoxicity of a theaflavin mixture from black tea to malignant, immortalized, and normal cells from the human oral cavity.

The growth inhibitory effects of a theaflavin mixture from black tea were more pronounced to malignant (CAL27; HSC-2; HSG1) and immortalized (S-G; GT1) cells than to normal (HGF-2) cells from the human oral cavity. Studies with malignant carcinoma CAL27 cells and immortalized GT1 fibroblasts showed that cytotoxicity of the theaflavin mixture was enhanced as the exposure time was increased, with the tumor CAL27 cells more sensitive than the GT1 cells. Hydrogen peroxide (H(2)O(2)) was detected in cell culture medium amended with the theaflavin mixture. The level of H(2)O(2) in cell culture medium amended with the theaflavin mixture was lessened in the presence of catalase and CoCl(2); the level of authentic H(2)O(2) was also lessened in the presence of CoCl(2), suggesting that Co(2+) led to the rapid catalytic decomposition of H(2)O(2). The cytotoxicity of the theaflavin mixture was due, in part, to the generation in the cell culture medium of H(2)O(2), which lessened the intracellular levels of glutathione in the CAL27 cells and, to a lesser extent, in the GT1 cells. For both cell types, coexposures of the theaflavin mixture with catalase or CoCl(2) afforded protection.

Biflavonoids↗
PubMed1989

Preoperative imaging in primary hyperparathyroidism. Role of thallium-technetium subtraction scintigraphy.

Primary hyperparathyroidism, although often silent clinically, may lead to significant morbidity if it remains untreated. In more than 95% of all cases the cause is a parathyroid adenoma or glandular hyperplasia. Regression of disease follows successful surgical excision of the abnormal parathyroid gland. Recurrent or persistent hyperparathyroidism is most commonly caused by solitary adenomas, which may have an ectopic location. Preoperative localization of lesions may improve postoperative cure rates and decrease morbidity. Thallium T1 201 chloride-technetium Tc 99m pertechnetate subtraction scintigraphy was performed on 15 patients with primary hyperparathyroidism. The sensitivity and specificity for detection of abnormal glands were 90% and 95%, respectively. False-positive or false-negative results were minimize by strict adherence to a protocol and by the use of well-defined diagnostic criteria. Because of the superior sensitivity and specificity, this modality should be the primary imaging method of choice for preoperative evaluation of primary hyperparathyroidism. The relative role of other imaging modalities is also discussed.

Adenoma↗
PubMed1988

The use and diagnostic significance of thallium-201 SPECT imaging in a case of anomalous left coronary artery.

A 6-year-old female with an anomalous left coronary artery (ALCA) originating from the main pulmonary artery underwent a resting Tl-201 SPECT examination before and after surgical reimplantation. Preoperative Tl-201 SPECT images demonstrated decreased perfusion to the anterior wall and a dilated left ventricle. Post operative Tl-201 SPECT images showed marked improvement of perfusion to the anterior wall as well as a decreased left ventricular size. This is one of the few documented demonstrations of a perfusion defect due to an ALCA in a young child using Tl-201 SPECT imaging methods in conjunction with other tests.

Child↗
PubMed1986

Radiation-induced thyroid carcinoma. Clinical course and results of therapy in 296 patients.

Of 5379 patients who had received radiation treatment at our institution for benign conditions of the head and neck, 318 developed thyroid cancer 3 to 42 years later. We report follow-up observations (median interval from diagnosis to recurrence or last contact, 10 years; longest interval, 31) for 296 of these patients. Three patients died of thyroid cancer and 40 had recurrences. The rate of recurrence during the 10 years after the detection of thyroid cancer, determined by life-table analysis, was 1.1%/yr. Factors that correlated with the risk of recurrence were tumor size, histologic type, number of lobes involved, vessel invasion, and lymph node metastases. The time from radiation exposure to the discovery of thyroid cancer (latency) and the age at diagnosis both inversely correlated with recurrence. The administration of thyroid hormones reduced the number of recurrences in patients with combined papillary and follicular cancer, but no reductions could be associated with the extent of surgery done or the prophylactic use of radioactive iodine ablation. We conclude that the course of radiation-induced thyroid cancer is the same as that of thyroid cancer found in other settings. We advocate a conservative approach to the treatment of small tumors that have no associated risk for thyroid cancer other than that they developed many years after the patient had been exposed to radiation.

Actuarial Analysis↗
PubMed1985

Gastric ulcer localization by direct in vivo labeling of sucralfate. Work in progress.

We developed and evaluated a new procedure for imaging gastric ulcer disease with technetium 99m-labeled sucralfate. The new method employs direct in vivo labeling of sucralfate instead of in vitro labeling using human serum albumin, as previously reported in the literature. Tests using hydrochloric acid and a rabbit ulcer model showed the efficacy of the direct in vivo labeling technique and the ability of the tagged material to bind to ulcers, respectively. In 26 studies using humans with sucralfate labeled directly in vivo, 15 gave true-negative results and 11 gave true-positive results. Of 14 studies using humans with in vitro labeled sucralfate, three gave true-negative results, three gave true-positive results, and the results of eight were either false-negative or could not be interpreted because of high levels of activity remaining in the stomach. We suggest that the direct in vivo labeling method significantly improves the sucralfate gastric ulcer imaging technique.

Aluminum↗
PubMed1985

Prospective serum thyroglobulin measurements in assessing the risk of developing thyroid nodules in patients exposed to childhood neck irradiation.

We examined 327 patients with a history of cervical radiation treatment for benign conditions and followed them for an average of 5.6 yr. These patients were selected because they initially had normal examinations and normal serum thyroglobulin levels. Of the 327 patients, 48 developed thyroid nodules, and an additional 30 had other clinical changes in their thyroids. Serum thyroglobulin increased by 4.0 +/- 0.6 (+/- SEM) ng/ml in those who remained normal, by 13.4 +/- 5.2 ng/ml in those who were no longer normal, and by 17.1 +/- 8.2 ng/ml in those who developed nodules. We conclude that increasing levels of serum thyroglobulin identify patients who should be examined and followed more carefully for thyroid nodules and thyroid cancer.

Age Factors↗
PubMed1984

Visualization of the liver, gallbladder, and intestine on bone scintigraphy.

Images of the liver, gallbladder, and/or intestine were visualized on bone scans on several occasions. Radiopharmaceutical quality control data, including molybdenum-99 and aluminum ion content in the Tc-99m eluate, free unbound Tc-99m, and hydrolyzed reduced Tc-99m in the labeled MDP, were all satisfactory. A minor defect in the quality of the Tc-99m generator was considered to be the probable cause of the unusual localization of the bone imaging agent.

Bone and Bones↗
PubMed1984

Metastatic calcification of the stomach imaged on a bone scan.

A whole body bone scan obtained on a 21-year-old woman with sickle cell disease and chronic renal failure showed localization of the radionuclide diffusely in the stomach. The localization of the radionuclide represented metastatic calcification of the stomach caused by secondary hyperparathyroidism.

Adult↗
PubMed1983

Thyroid imaging agents: a comparison of I-123 and Tc-99m pertechnetate.

Tc-99m pertechnetate and I-123 were used to perform thyroid scanning in 122 patients with history or clinical evidence of thyroid disease. Thyroid scans were abnormal in all patients, while thyroid palpation was abnormal in all but 19. The quality of thyroid imaging was similar with both agents in 42%, better with I-123 in 18%, and better with Tc-99m in 7%. In the remaining 33% (40 cases), there were discrepancies between Tc-99m and I-123 images. The most frequent discrepancies were "hot" or "warm" lesions on Tc-99m scans that were "cold" or normal on I-123 scans. Results from this study indicate that neither Tc-99m nor I-123 is always superior to the other as a thyroid imaging agent.

Adult↗
PubMed1982

Gallium 67 citrate scanning and serum angiotensin converting enzyme levels in sarcoidosis.

Gallium 67 citrate scans and serum angiotensin converting enzyme (ACE) levels were obtained in 54 patients with sarcoidosis and analyzed in relation to clinical manifestations. 67Ga scans were abnormal in 97% of patients with clinically active disease (n = 30) and in 71% of patients with inactive disease (n = 24). Serum ACE levels were abnormally high (2 standard deviations above the control mean) in 73% of patients with clinically active disease and in 54% of patients with inactive disease. Serum ACE levels correlated significantly with 67Ga uptake score (r =.436; p less than .005). The frequency of abnormal 67Ga scans and elevated serum ACE levels suggests that inflammatory activity with little or no clinical expression is common in sarcoidosis. Abnormal 67Ga scans were highly sensitive (97%) but had poor specificity (29%) to clinical disease activity. The accuracy of negative prediction of clinical activity by normal scans (87%) was better than the accuracy of positive prediction of clinical activity by abnormal scans (63%). 67Ga scans can be used to support the clinical identification of inactive sarcoidosis.

Adult↗
PubMed1980

Dose calibrator readings due to radionuclidic impurities found in radiopharmaceuticals.

The influence of the radionuclidic impurities in radiopharmaceuticals on the reading of sample activities in a dose calibrator has been studied. As a practical example, commercially available 123I was used to measure the effect of radioactive impurities on "dose calibrator" readings. The impurities present in commercially available 123I were identified and quantified by the use of a Ge(Li) detector, and the response of a dose calibrator to each impurity was determined. The contribution of radioactive impurities to sample readings was determined for each sample of 123I studied. It was found that impurities may increase the dose calibrator readings up to 31%, even though the impurities were within the warranty given by the manufacturer.

Iodine Radioisotopes↗
PubMed1978

Extensive metastases in Peutz-Jeghers syndrome.

A 27-year-old woman with Peutz-Jeghers syndrome since age 11 years was hospitalized with a sudden onset of weakness of the right extremity, an expressive aphasia, and a three-month history of back pain. Liver and whole-body scintigrams demonstrated multiple metastatic disease; the brain scintigraphic study was compatible with infarction of the left hemisphere. Postmoretem examination two weeks after these studies showed extensive metastases in bone, liver, brain, lung, and left ovary. The source of the metastases was a malignant change from Peutz-Jeghers polyps.

Adenocarcinoma↗
PubMed1978

Adrenal scanning and uptake with 131I-6beta-iodomethyl-nor-cholesterol.

Adrenal scans were obtained in 50 patients with suspected adrenal disease; 131I-19-iodocholesterol was used in 12 and 131I-6-beta-iodomethyl cholesterol (NP-59) in 38 cases (42 scans). The scan diagnosis was correct in 48 patients. Successful images were obtained with 0.5 mCi, or less, of NP-59 instead of the standard dose of 2 mCi, thus reducing radiation dose to the patient and cost of the agent. Satisfactory scans were obtained in 2--3 days in patients with hyperfunctioning adrenals, and in 3--7 days in other groups of patients, when NP-59 was used. With 131I-19-iodocholesterol, however, 5--10 days were required for optimal results in all patients including those with Cushing disease. Adrenal uptake studies were very useful in the evaluation of adrenal function, particularly in differentiating bilateral hyperplasia from normal adrenals.

Adrenal Gland Diseases↗
PubMed1977

Arteriovenous malformation simulating Meckel's diverticulum on 99mTc-pertechnetate abdominal scintigraphy.

99mTc-pertechnetate scintigraphy in a 67-year-old woman with chronic gastrointestinal bleeding showed an area of increased activity in the right lower quadrant which appeared at the same time the stomach was visualized. At first this was thought to be a Meckel's diverticulum; however, superior mesenteric angiography subsequently revealed a small arteriovenous malformation which proved to be the bleeding site on laparotomy. This false-positive finding emphasizes the importance of comparative evaluation of early and late images in scintigraphy for suspected Meckel's diverticulum.

Aged↗