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Biomedical subjects

R P Feldman

Publications and source records attributed to R P Feldman.

12 recordsLinked to original sources
PubMed2001

Psychosurgery: a historical overview.

Neurosurgical treatment for psychiatric disorders has a long and controversial history. From the Stone Age use of trephining to release the demons of the spirit to the millimeter accuracy of stereotactic instruments currently used in the operating room, psychosurgery has enjoyed enthusiastic support as well as experiencing scorn. Today, psychosurgery is a minimally invasive and highly selective treatment that is performed for only a few patients with severe, treatment-refractory, affective, anxiety, or obsessive-compulsive disorders. Recent advances in technology and functional neuroanatomic techniques, as well as economic pressures to decrease the costs of caring for chronically ill patients, may provide an opportunity for psychosurgery to become a more attractive option for the treatment of psychiatric diseases. In this historical overview, the rise and fall of psychosurgery are described. A better understanding of the colorful history of this interesting topic should enable modern neurosurgeons and other health care professionals to meet the social, ethical, and technical challenges that are sure to lie ahead.

History, 17th Century↗
PubMed2001

Intracranial lipoma of the sylvian fissure. Case report and review of the literature.

The authors present a rare case of lipoma of the sylvian fissure found in a 34-year-old man who presented with seizures. The patient underwent craniotomy and an attempted resection of the lesion, which was initially believed to be a dermoid tumor. The imaging characteristics of dermoids and lipomas are extremely similar. Given the difference in the natural history and resectability of these lesions, lipomas should be included in the differential diagnosis of lesions with imaging characteristics similar to dermoids. Currently, tumor location, density of the lesion or computerized tomography scans, and signal homogeneity of the lesion on magnetic resonance images can help one to distinguish these radiographically similar, but pathologically different, entities. As this case confirms, resection of a sylvian fissure lipoma is extremely difficult and potentially dangerous; in addition it is unlikely to improve symptoms. A short review of 10 cases reported in the literature and therapeutic options for these lesions are also discussed.

Adult↗
PubMed2001

Contemporary psychosurgery and a look to the future.

OBJECT: Despite a long and controversial history, psychosurgery has persisted as a modern treatment option for some severe, medically intractable psychiatric disorders. The goal of this study was to review the current state of psychosurgery. METHODS: In this review, the definition of psychosurgery, patient selection criteria, and anatomical and physiological rationales for cingulotomy, subcaudate tractotomy, anterior capsulotomy, and limbic leukotomy are discussed. The historical developments, modern procedures, and results of these four contemporary psychosurgical procedures are also reviewed. Examples of recent advances in neuroscience indicating a future role for neurosurgical intervention for psychiatric disease are also mentioned. CONCLUSIONS: A thorough understanding of contemporary psychosurgery will help neurosurgeons and other physicians face the ethical, social, and technical challenges that are sure to lie ahead as modern science continues to unlock the secrets of the mind and brain.

Humans↗
PubMed1999

The Edwin Smith Surgical Papyrus.

The Edwin Smith Surgical Papyrus is undoubtedly one of the most significant medical texts ever discovered. It is of particular interest to neurosurgeons because of its specific references to ancient neurosurgical cases and is the first written record of many terms of neurosurgical interest. This review describes the colorful and controversial history of the Edwin Smith Papyrus and gives translations of four cases of neurosurgical interest.

Archaeology↗
PubMed1999

Foreign body granuloma mimicking intracranial meningioma: case report and review of the literature.

OBJECTIVE AND IMPORTANCE: Intracranial foreign body granulomas are rare. We describe a case of an intracranial foreign body granuloma found in a 17-year-old female patient 9 years after she underwent a craniotomy for a tumor of unknown type. Postoperative imaging of patients who have undergone neurosurgical procedures can often reveal enhancing masses, and foreign body granuloma should be included in the differential diagnosis. CLINICAL PRESENTATION: The patient presented with a history of developmental delay, panhypopituitarism, and chronic headache. Admission resulted from an acute increase in the severity of her headache. INTERVENTION: Imaging studies, including computed tomography and magnetic resonance imaging, demonstrated a 1.5 x 2 cm round, enhancing anterior interhemispheric mass, appearing to arise from the falx and causing mild mass effect. A nonenhancing cystic mass was also noted in the suprasellar region but was without mass effect. The patient underwent a craniotomy and removal of the anterior mass without complication, and her headache resolved. A pathological examination of the specimen confirmed the diagnosis of foreign body granuloma. CONCLUSION: Although rare, foreign body granuloma should be included in the differential diagnosis of previously operated intracranial masses. The importance of accurate historical information and guidelines that may assist in diagnosis are discussed.

Adolescent↗
PubMed1991

Isolation of mitotic p34cdc2 apoenzyme from human cells.

A simple procedure was devised for isolating from homogenates of mitotic cells the human homolog to the fission yeast cdc2 gene product. The identity of the purified protein was established with anti-p34cdc2 antibodies and p13suc 1, both specific ligands for p34cdc2. Active-site labeling with oxidized [alpha 32P]ATP showed the purified molecule to be an ATP-binding protein. Its ability to phosphorylate casein but not histone, and its phosphorylation on tyrosine, detected by anti-phosphotyrosine antibodies, indicates the form of p34cdc2 purified is the inactive or apoenzyme form. Purified quantities of human p34cdc2 should be of considerable value in establishing the mechanism of its activation at mitosis by phosphatases.

Apoenzymes↗
PubMed1981

Effect of several metal ions on misincorporation during transcription.

By use of poly(dA-dT) as template and Escherichia coli RNA polymerase, several metal ions were tested for their effect on the efficiency of transcription and on the misincorporation of CMP into the poly(rA-rU) product. In the presence of 10 mM MgCl2, Mn2+ has a stimulatory effect on the transcription, Co2+ has very little effect on the reaction, Cu2+ and Zn2+ are strongly inhibitory, and Cd2+ and Ni2+ are less inhibitory. The background misincorporation of CMP in the presence of MgCl2 is about 1 nucleotide per 2000 correct nucleotides incorporated and is independent of Mg2+ concentration. Zn2+, Ca2+, Sr2+, Li+, Na+, and K+--all nonmutagenic and noncarcinogenic--do not increase misincorporation. Mn2+ causes a concentration-dependent threefold increase in the misincorporation that can be slightly reversed at higher MgCl2 concentrations. Cd2+ causes a dramatic increase in the misincorporation with increasing CdCl2 concentration that can be substantially overcome by higher concentrations of Mg2+. Cu2+ also increases the misincorporation, Ni2+ slightly increases it, and Co2+ does not increase it at all. Several control experiments indicate that the misincorporation of CMP is dependent on the template-directed synthesis of poly(rA-rU). Nearest-neighbor analysis indicates that CMP is incorporated in place of UMP into the poly(rA-rU) product. The increase in misincorporation appears to be related both to the "hard-soft" character of the metal ions and to their carcinogenic potential.

Cations↗
PubMed1981

Selective effects of metal ions on RNA synthesis rates.

The effects of 14 metal ions (chlorides) on the transcription of calf thymus DNA and phage T4 DNA with Escherichia coli RNA polymerase were tested. These assays were conducted under improved conditions of lower pH and in the absence of 2-mercaptoethanol to permit greater stability of the metal ions in solution. Among the divalent metal ions tested, the concentration-dependent order of inhibition of overall transcription is Pb2+ greater than Zn2+ greater than Cu2+ greater than Be2+ greater than Cd2+ greater than Ni2+ greater than Ca2+ greater than Co2+ greater than Mn2+ greater than Mg2+ greater than Sr2+ and is the same with either template. At pH 7.4 and in the absence of 2-mercaptoethanol, considerably lower concentrations of several of the divalent metal ions are needed for inhibition of overall transcription than at pH 8.1 and in the presence of 2-mercaptoethanol. Ca2+, Mg2+, Sr2+, Zn2+, Li+, Na+, and K+--considered to be non-mutagenic and non-carcinogenic--decrease chain initiation (measured with T4 DNA) at concentrations that inhibit overall transcription. Pb2+, Cd2+, Co2+, Be2+, and Mn2+--all mutagenic or carcinogenic--stimulate chain initiation (although at widely different rates) at concentrations that inhibit overall transcription. Cu2+ and Ni2+--both carcinogenic--stimulate initiation only at very low concentrations, followed by a progressive decrease in initiation at concentrations that inhibit overall transcription.

Animals↗
PubMed1977

L-ascorbate 2-sulfate and mobilization of cholesterol from plaque deposited in rabbit aortas.

Rabbits were randomly assigned to two groups. Age and body weight distribution were equal in both groups. All animals were placed on a high cholesterol diet for 9 wk, then returned to a normal diet for 1 wk. At the end of this dietary regimen, one group of animals received subcutaneous injections of psysiological saline 3 times/day, 5 days/wk for 10 wk, and the other group recieved L-ascorbate 2-sulfate (0.37 mmole) according to the same timetable. On alternate weeks, the serum levels of total and free cholesterol were determined. After 10 wk of treatment the animals were killed; the plaques were excised from the aortas and examined for total mass and cholesterol content. We observed that, under these dietary conditions, L-ascorbate 2-sulfate does not mobilize cholesterol or its esters from preformed aortic plaque. However, we did observe that animals showing high cholesterol levels in their sera died prematurely when injected with L-ascorbate 2-sulfate. Gross and histopathological investigations of organs and tissues did not reveal any significant differences among the animals that died prematurely and those that survived to the termination of the experiment.

Animals↗
PubMed1976

L-ascorbic acid, L-ascorbate 2-sulfate, and atherogenesis.

Rabbits on a high cholesterol diet were divided into three groups: one group received subcutaneous injections of physiological saline 3 times/day, 5 days/wk for 10 wk; another group received subcutaneous injections of L-ascorbic acid (0.37 mmole) according to the same timetable; and the third group was administered an equivalent amount of L-ascorbate 2-sulfate as outlined above. Each week the serum levels of total and free cholesterol and triglycerides were measured. At the end of 10 wk the animals were killed and the cholesterol content of the livers, spleens, and adrenal glands was measured. The aortas were examined for plaque deposition; the deposits were excised and pooled according to groups; and the total mass and cholesterol contents of the pooled plaques were determined. Administration of ascorbic acid or ascorbate 2-sulfate did not prevent hypercholesterolemia or elevated levels of serum triglycerides. No significant differences among the groups were found either in tissue cholesterol levels or in the extent or type of lesions found. Although plaque deposition appeared to be similar in the aortas of these animals, a marked difference was found in total mass and cholesterol content of the plaques: The plaques of the saline-treated group had a total mass and cholesterol content approximately 2.5 times that found in the group injected with ascorbic acid and about 1.5 times that found in the animals treated with ascorbate 2-sulfate. These results indicate that ascorbic acid, in particular, minimizes the total quantity of plaque deposition even though it is ineffective in preventing hypercholesterolemia, elevated serum triglycerides, and accumulation of cholesterol by several tissues.

Adrenal Glands↗