Search PubMed⌕ Search

Biomedical subjects

S Goldman

Publications and source records attributed to S Goldman.

At least 433 records · Page 24Linked to original sources

L-amino acid load to enhance PET differentiation between tumor and inflammation: an in vitro study on (18)F-FET uptake.

Labeled amino acids (AA) are tumor tracers for use in nuclear medecine. O-(2-[(18)F]fluoroethyl)-L-tyrosine (FET) is transported by the L-system, known to function as an exchanger. In vitro utilization of FET, after a preload or prior to an afterload of non radioactive L-amino acids, was evaluated in order to measure the potential effects of AA content on the distinction between tumor and inflammatory lesions. Cellular uptake of FET was studied on rat osteosarcoma cells (ROS 17/2.8) and human leukocytes, initially loaded with nonradioactive L-tyrosine or L-methionine. FET efflux was evaluated from cells loaded with nonradioactive L-phenylalanine after tracer uptake. ROS 17/2.8 showed a higher sensitivity to preload and afterload effects on cellular FET content as compared with the leukocytes. We conclude that preload with L-tyrosine, prior to the administration of FET, may be a potential procedure to improve PET differentiation between tumor and inflammatory lesions.

Amino Acids↗

Renocolic fistulas: complementary roles of computed tomography and direct pyelography.

Three patients with renocolic fistulas are presented. Antegrade or retrograde pyelography showed the fistula in one patient but was unsuccessful in two others. CT demonstrated perinephric inflammation extending to the colon, complex air-fluid collections within the kidney, or extension of renal contrast into the colon. CT and direct pyelography complement each other for the diagnosis of renocolic fistulas.

Aged↗

Distribution of neuropeptide Y immunoreactivity in human visual cortex and underlying white matter.

Immunocytochemical techniques have been used to study neuropeptide Y (NPY) distribution in the human visual cortex (Brodman's areas 17, 18 and 19) NPY cell bodies belong mostly to inhibitory (multipolar and bitufted) but also to excitatory (bipolar and some pyramidal) neuronal types. Their distribution is similar in the three cortical areas studied: 20 to 40% of the NPY perikarya are located in the cortical gray matter, mostly in the deep layers, while the remaining 60 to 80% are located in the underlying white matter. Immunoreactive NPY processes form a rich network of intersecting fibers throughout the entire visual cortex. A superficial plexus (layers I and II) and a deep plexus (deep layer V and layer VI) of NPY fibers are present in areas 17, 18 and 19. In area 17, an additional well developed plexus is present in layers IVb and IVc. These plexuses receive branches from long parallel fibers arising from deep cortical layers or underlying white matter and terminating in superficial layers. Local or extrinsic NPY terminals wind around vessels in the cortex as well as in the white matter, and either penetrate them or form clusters of club endings on their walls. Our results suggest a role for NPY in human visual circuitry and in cortical blood flow regulation.

Aged↗

Brain glucose metabolism in borderline personality disorder.

We searched for regional cerebral metabolic disturbances in patients with borderline personality disorder (BPD). Ten inpatients with BPD, no current DSM-IIIR Axis I diagnosis and free of any psychotropic substances, were compared with 15 age-matched control subjects using positron emission tomography with 2-deoxy-2-[18F]fluoro-D-glucose and semiquantitative analysis of regional glucose metabolic activity. We found relative hypometabolism in patients with borderline personality disorder at the level of the premotor and prefrontal cortical areas, the anterior part of the cingulate cortex and the thalamic, caudate and lenticular nuclei. This study shows significant cerebral metabolic disturbances in patients with borderline personality disorder. These metabolic disturbances, which are similar to some of those described in other psychiatric entities, may help to understand the characteristic clinical aspects of this disorder.

Adult↗

Anomalous origin of the right coronary artery from the pulmonary artery.

A 35-year-old woman was seen because of a two-year history of exertional dyspnea. She had a high-pitched systolic and diastolic murmur and evidence of left ventricular hypertrophy. Increased hemoglobin oxygen saturation was noted as the level of the pulmonary trunk, and indocyanine green dye curves were characteristic of a left-to-right shunt. Aortic root angiography revealed that the right coronary artery arose from the pulmonary trunk and that blood flow was reversed. The incidence, clinical manifestations, and therapy of this rare syndrome are reviewed.

Adult↗

Effects of alpha 2-adrenergic stimulation with UK 14,304-18 on the heart and peripheral circulation of intact dogs.

To determine the extent of alpha 2-adrenoreceptor control of cardiovascular function, we studied the hemodynamic effects of the relatively selective alpha 2-adrenergic agonist UK 14,304-18 on the heart and peripheral circulation of intact dogs. Administration of increasing intravenous doses of UK 14,304-18 to conscious dogs given atropine to maintain heart rate (HR) resulted in a reproducible increase in mean aortic (AO) pressure (77.6 +/- 5.0 to 136.4 +/- 6.5 mm Hg, p less than 0.05) and reductions in stroke volume (31.7 +/- 2.9 to 17.9 +/- 1.9 ml/kg/min, p less than 0.05) and left ventricular (LV) dP/dt (2,120 +/- 280.0 to 1,463 +/- 196.1 mm Hg/s, p less than 0.05). In ganglion-blocked dogs UK 14,304-18 did not alter the slope of the LV end-systolic pressure-volume relationship when compared with angiotensin and nitroprusside (79.9 +/- 11.1 control vs. 73.3 +/- 8.7 mm Hg/ml/kg UK 14,304-18, p greater than 0.05), nor did it change the volume intercept (-0.46 +/- 0.12 control vs. -0.53 +/- 0.16 ml/kg UK 14, 304-18, p greater than 0.05) indicating no direct effect on LV contractile function. Changes in indices of diastolic function, including the time constant of isovolumic relaxation, time to peak filling, and chamber volume elasticity were similar to those of equipressor doses of angiotensin, indicating no direct effect on LV diastolic function. Effects on the peripheral circulation were studied in dogs undergoing transient acetylcholine-induced circulatory arrest. UK 14,304-18 increased mean circulatory filling pressure (7.9 +/- 0.3 to 10.3 +/- 0.2 mm Hg, p less than 0.05) and the pressure gradient for venous return (7.6 +/- 0.4 to 9.0 +/- 0.3 mm Hg, p less than 0.05). Central blood volume increased with UK 14,304-18 (15.6 +/- 1.1 to 18.7 +/- 1.5 ml/kg, p less than 0.05), but this increase was not sufficient to maintain cardiac output (CO) during the UK 14,304-18 infusion, which decreased from 157.4 +/- 11.1 to 131.5 +/- 8.9 ml/kg/min (p less than 0.01) in the presence of increased LV afterload. The time constant of relaxation of the arterial system increased and the arterial compliance decreased with increasing mean arterial pressure. Thus, this relatively selective alpha 2 agonist does not directly alter cardiac function but increased tone in arterial resistance vessels and in systemic veins. The fall in CO appears to be caused by a mismatch between preload and afterload, which is the net result of quantitatively different effects on systemic veins and arteries.

Adrenergic alpha-Agonists↗

How physicians use the stress test for the management of angina.

The authors examined physicians' reasons for ordering an exercise tolerance test and the influence of the test results on management decisions. Subjects of this study included 265 family physicians in Pennsylvania who completed a questionnaire on the management of a patient with typical chronic stable angina. Eighty-one percent of the respondents reported they would order a noninvasive stress test as a first step in the management of the patient. Of these physicians, 40% would refer the patient to a cardiologist only if the exercise tolerance test were strongly positive, 8% would refer only if it were negative, and 53% would not change their referral decisions on the basis of test results. No more than 57% of the physicians rated as very important any given reason for ordering a noninvasive diagnostic test. The results suggest that a test may be ordered routinely but without a consensus as to why it is ordered and without an effect on clinical management decisions.

Angina Pectoris↗

Clinical outcome in children with recurrent craniopharyngioma after primary surgery.

PURPOSE: The purpose of this article is to report the clinical outcome in children with recurrent craniopharyngioma after primary surgery. PATIENT AND MATERIALS: Fourteen children with craniopharyngioma treated with primary surgery developed local recurrence. The median time to recurrence from primary surgery was 19 months (range, 2-156 months). At first recurrence (n = 14), seven children (50%) underwent reoperation. Five children (36%) received radiotherapy, and two children did not undergo any treatment. At second recurrence (n = 7), six children underwent radiotherapy (86%), and one had surgery. External-beam radiation was delivered with 6-MV or 10-MV x-rays by use of three-dimensional conformal technique (n = 4) or fractionated stereotactic radiotherapy (n = 7) using the Laitinen stereoadapter. Total dose ranged from 54 to 55.8 Gy at 1.8 Gy/fraction. RESULTS: The median follow-up from primary surgery is 8.5 years (range, 3-15.8 years). The 5-, 10-, and 15-year overall survival was 100%, 86%, and 86%, respectively, and the disease-free survival was 92%, 60%, and 60%, respectively. The median follow-up from date of first relapse was 6 years (range, 2.5-10 years). After treatment for first recurrence, the 2- and 5-year second-recurrence-free survival was 71% and 29%, respectively. After radiotherapy, the 2- and 5-year second-recurrence-free survival was 100% and 100%, respectively, compared with 43% and 0%, respectively, for surgery alone. Univariate analysis revealed significantly superior local control with radiotherapy compared with surgery. The local control rate at last follow-up, after stratifying for treatment at first and second recurrence, were analyzed at first and second relapse was 90% and 0% after radiotherapy and surgery, respectively. If radiotherapy was used for first or second recurrence, the 5-, 10-, and 15-year relapse-free survival was 100%, 83%, and 83%, respectively, compared with 67%, 0%, and 0%, respectively, for surgery alone. The median time to second relapse after surgery for first relapse was 12 months (range, 2-36 months). After primary surgery, all 14 children developed panhypopituitarism, requiring lifelong hormone supplementation. After surgery at recurrence, three children (3/7, 43%) experienced intraoperative bleeding, resulting in permanent neurologic deficits in two. No child has shown any signs of radiation-induced optic neuropathy. DISCUSSION: In children with recurrent craniopharyngioma after radical resection, the use of three-dimensional conformal radiotherapy or fractioned stereotactic radiotherapy results in very good local control with a low incidence of complications. In young children with stable tiny recurrences, a policy of close surveillance could be adopted for the brain to mature before beginning radiotherapy. The use of secondary surgery for recurrent tumors is associated with a low cure rate and a high risk of complications.

Adolescent↗