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Biomedical subjects

S Kramer

Publications and source records attributed to S Kramer.

At least 199 records · Page 11Linked to original sources

Reduced ferrochelatase activity in fibroblasts from patients with porphyria variegata.

Ferrochelatase deficiency has been shown in both porphyria variegata (PV) and erythropoietic protoporphyria (EPP). It has been suggested that in PV there is a decrease in the enzyme, whereas in EPP the enzyme is unstable. In the present study ferrochelatase activity was measured in skin fibroblasts from three patients with PV and three normal subjects. The enzymatic activity in the patients with PV (17.5 +/- 4.5 pmoles heme formed per 10(7) fibroblasts per hour) was 50% of that of the control group (31.0 +/- 3.2 pmoles heme formed per 10(7) fibroblasts per hour). This supports the contention that the enzyme is deficient in PV and that an inactive ferrochelatase is the primary deficiency in this type of porphyria.

Fibroblasts↗

Optimum fractionation for irradiation of carcinoma of the bladder. Experiments based on one case.

A patient with multiple metastases of transitional cell carcinoma of the bladder to the skin and subcutaneous tissues proved a model where most of the biologic and host-related factors were constant. The effects of varying the physical factors of radiation dose and time were observed. The results indicate that fractionated irradiation at intervals of 48 h was more effective than at intervals of 24 h and that superfractionation (intervals of 5 h) was not an effective method for the treatment of this tumor. The possible reasons for this effect and the implication for the treatment of bladder carcinoma are discussed.

Carcinoma, Transitional Cell↗

The technical significance and application of Mahler's separation-individuation theory.

Greater knowledge and integration of developmental concepts and of the frame of reference of separation-individuation, add to the analyst's richer insights and to his more complete interpretations and reconstructions. Freud recognized the complexity of preoedipal development and the importance of the object and of object relations. Contemporary contributions have enabled us to proceed beyond the preoedipal conceptualizations of and since Freud, to better understand ego- and drive regression and evidence of fixations or ego distortions which may appear parallel to "normal neurotic" findings. I question whether we encounter different patients today and suggest that we understand our patients better, thus making our analytic assessments and practices so different from 50 years ago. Separation-individuation theory encompasses and organizes findings from many sources, research and clinical, and permits us to perceive and process material in a multifaceted way. It must affect the timing and content of interpretations and reconstruction, and has a profound influence upon the understanding of psychopathology as well as normal development.

Adult↗

Measuring the quality of medical care: a beginning.

Quality of medical care is fundamental; however, the recognition of quality is a complex task. The Patterns of Care Study is examining radiotherapeutic care in cancer throughout the United States, using a new methodology which can be applied to other medical disciplines. The system is described and illustrated as applied to the management of carcinoma of the cervix. Considerable variations in treatment have been identified. These variations can be studied and, where necessary, modified by appropriate educational programs; thus, the quality of medical care can be improved.

Decision Making↗

Porphyria variegata--studies of an affected couple and their children.

Porphyria variegata affects approximately 1 in 200 Afrikaans-speaking people in South Africa. This paper reports the first case of a marriage between 2 people with porphyria variegata and describes investigations carried out on their 2 children, who do not exhibit any signs of the disease. The wife had suffered 1 miscarriage at 4 months' gestation.

Adult↗

Fanconi's anaemia, with special reference to erythrokinetic features.

Serial haematological investigations were carried out in 5 patients with Fanconi's anaemia over periods of 6 months--11 years. All the patients were pancytopenic with a depression of the granulocytic and megakaryocytic elements of the bone marrow throughout the greater part of their illnesses. Erythropoietic acitvity was variable. The initial bone marrow examination revealed depressed erythroid function in 3 patients. The erythroid hypoplasia persisted in 2 of them, while in the third, erythroid activity increased with time, possibly as the result of therapy with oxymetholone. Erythroid hyperplasia was present in the remaining 2 patients, both at presentation and throughout the course of the illness. This could not be attributed to treatment in either patient. Six erythrokinetic studies were carried out in the 5 patients at variable intervals after the diagnosis had been made. In 2 studies erythroid activity was unequivocally depressed, while in a further 3 a significant, though probably suboptimal, erythroid marrow response was present. In the final study erythropoiesis was increased but was markedly ineffective in terms of the delivery of viable red cells into the circulation. In vivo counting suggested that some degree of ineffective erythropoiesis was also present in the other patients and studies with 51Cr indicated a shortened red cell survival in all subjects studied. In 2 of them significant splenic sequestration was present. Leukaemic transformation occurred in 2 patients. In 1 of them its development was heralded by the appearance of micromegakaryocytes in the bone marrow.

Adolescent↗

The value of computerized tomography in delineating suprasellar extension of pituitary adenoma for radiotherapeutic management.

Radiotherapy plays a major role in the management of pituitary adenomas, either as a surgical adjunct or as the primary form of treatment. Small field precision techniques are utilized. The ability to employ limited field therapy and produce local control rates of 80--90% demands precise tumor localization. The extrasellar extension of pituitary adenomas has classically been demonstrated on angiographic and pneumoencephalographic examinations. Direct superior extension is accurately delineated by these examinations; lateral extension, however, is not and the total anterior-posterior extent of the tumor may be underestimated. The addition of computerized tomography significantly increases the information available in the assessment of tumor extension and the subsequent accuracy of treatment planning for radiotherapeutic purposes.

Adenoma↗

Participation of the anterior hypothalamus in the regulation of arterial blood pressure.

Bilateral electrolyte lesions of the Anterior Hypothalamus (AH) were placed in rats to determine the extent to which this area participates in the regulation of Arterial Blood Pressure (ABP). Experiments were performed in two groups of rats; in one ABP was measured continuously for 44 hr subsequent to the lesion, and in a second group ABP was measured 24 hr after the placement of the lesion. The destruction of this area results in a rapid development of arterial hypertension, hypermotility and hyperexcitability. 24 hr later these effects are attenuated. We conclude that arterial hypertension is probably due to a disinhibition of sympathetic activity through central interruption of baroreceptors reflexes.

Animals↗

The Radiation Therapy Oncology Group: a progress report.

The Radiation Therapy Oncology Group (RTOG), founded in 1971, comprises 35 university hospitals which are participating in 21 active protocols, four registries and eight pilot studies, including Phase I/II studies. Case accession has grown to over 1000 in 1977 with 19,801 patients being entered in the RTOG initial registration. Goals of the RTOG include: advancing knowledge of the role of radiation therapy in disease management; improving control of primary and regional disease; reducing morbidity and complications from treatment; and collaborating with other oncology disciplines to obtain data on multimodality therapy.

Clinical Trials as Topic↗

Adjuvant radiotherapy--preoperative, postoperative, or both: a proposal for a new approach.

A new approach to adjuvant radiotherapy is presented using a "sandwich technique" of low-dose preoperative irradiation (500 rads) and high-dose postoperative irradiation (4500 rads in 5 weeks) in the treatment of operable carcinomas of the rectum and bladder. The rationale for this approach and the preliminary results of a pilot study in 28 patients (19 with carcinoma of the rectum and nine with carcinoma of the bladder) are presented. This appears to be a very feasible and logical approach to treatment, with very few complications and excellent local control of disease.

Humans↗

Radiation therapy as initial treatment for early stage cancer of the breast without mastectomy.

This report describes 150 patients with clinical stage I and II carcinoma of the breast treated at four institutions--Yale University School of Medicine, Harvard Medical School-Joint Center for Radiation Therapy, Hahnemann Medical College, Jefferson Medical College--with radiotherapy only following excisional biopsy. Closely similar treatment policies were followed at all four centers, 4500-5000 rads minimum tumor dose being delivered to the entire breast and axillary, supraclavicular and internal mammary nodes. Forty-six of 49 stage I patients treated are alive without disease, the actuarial relapse-free survival being 91% at 5 years. Of the 101 stage II patients, 75 are alive without disease with a relapse-free actuarial survival of 60% at 5 years. Local failure has occurred in 10 patients (9 stage II and 1 stage I, 6.6%) 5 of whom are disease-free following mastectomy. The results obtained in this study are comparable to those of conventional surgery. It is our conclusion that mastectomy is not a necessary part of the treatment of small breast cancers, that radiation without mastectomy is an acceptable alternative with far superior cosmetic and functional results. Adjuvant chemotherapy should be considered particularly in stage II patients in view of their 40% relapse rate.

Antineoplastic Agents↗

The neurological manifestations of porphyria: a review.

The hereditary hepatic porphyrias, PV, AIP and HC, are characterized biochemically by increased excretion of porphyrins and the porphyrin precursors ALA and PBG. They are characterized clinically by episodes of acute neurological involvement. The increased production of porphyrins and porphyrin precursors has been shown to be due to partial enzyme blocks along the heme biosynthetic pathway which results in secondary depression of the key enzyme ALA-synthetase. The neurological manifestations could therefore be related to either a decrease in essential heme-proteins or other heme-containing compounds within the nervous system, or to a toxic effect of the over-production of the porphyrin precursors ALA and PBG. There is evidence for and against both theories. Recent work from a number of research groups has shown the porphyrin precursors to have potent pharmacological effects on the nervous system, and these are possibly related to the GABA receptor and binding site-porphyrin precursor interactions. Current studies on therapy of the acute attack have concentrated on suppression of ALA-synthetase activity, and consequently, on reduced ALA and PBG production. A number of such methods of therapy have met with remarkable success and hold promise for the future treatment of the acute attack.

Acute Disease↗

Reduced ferrochelatase activity: a defect common to porphyria variegata and protoporphyria.

Erythroid ferrochelatase activity has been studied in the normoblasts of patients with porphyria variegata and protoporphyria. Two methods were used for the investigation: one using intact cells and the other lysed cells, each measuring the amount of haem synthesized by normoblasts. In patients with porphyria variegata, ferrochelatase activity estimated by both methods was approximately 50% of the normal, and in protoporphyria the ferrochelatase activity was normal in intact normoblasts but was 20% of the normal in sonicated normoblasts (marrow lysates). It is suggested therefore that in porphyria variegata a dominantly inherited structural gene mutation results in an active ferrochelatase whereas in protoporphyria the genetic mutation results in an unstable ferrochelatase. The mechanism of the enzyme instability is not known though a number of postulates are discussed.

Adolescent↗