Biomedical subjects
I Klein
Publications and source records attributed to I Klein.
Protein degradation in acute cardiac loading: the problem of reutilization of amino acids.
Explore the source record for details and available documents.
Substrate preference and metabolic activity of the aerobic and the hypoxic turtle heart.
Explore the source record for details and available documents.
Solubilized myocardial adenylate cyclase. Restoration of histamine responsiveness by phosphatidylserine.
We have recently described the preparation of a solubilized cat myocardial adenylate cyclase which is unresponsive to histamine, norepinephrine, glucagon, and thyroxine, the hormones which activate the particulate enzyme. Since hormone receptors may consist of proteins and phospholipids, we determined the effect of several phospholipids on restoring the responsiveness of the solubilized adenylate cyclase to histamine. The addition of phosphatidylserine completely restored the histamine-mediated activation of the solubilized enzyme in contrast to phosphatidylethanolamine and phosphatidylinositol which were without effect. The concentration of histamine producing half-maximal activation of adenylate cyclase, 2 x 10(-5) M, was virtually identical with that observed in the particulate preparation. The antihistamine, diphenhydramine, 8 x 10(-5) M, abolished activation of adenylate cyclase by histamine in both the solubilized and particulate preparations. Phosphatidylserine also restored glucagon responsiveness, but did not restore norepinephrine responsiveness. It would appear that phosphatidylserine produced the necessary molecular configuration of the adenylate cyclase for histamine binding and activation of the enzyme.
Early changes in acute cardiac overload: studies on adenyl cyclase activity, cyclic 3'5'-AMP, and myosin synthesis.
Explore the source record for details and available documents.
Effect of prostaglandins on guinea pig myocardial adenyl cyclase.
Explore the source record for details and available documents.
Activation of myocardial adenyl cyclase by histamine in guinea pig, cat, and human heart.
Histamine has positive inotropic and chronotropic effects on the heart which are not abolished by beta adrenergic-blocking agents. Since the positive inotropic and chronotropic effects of other hormones on the heart are thought to be mediated by cyclic 3',5'-AMP, we examined the effect of histamine on adenyl cyclase in particulate preparations of guinea pig, cat, and human myocardium. Histamine at the peak of its dose-response curve, 3 x 10(-4)moles/liter, produced approximately a 300% increase in cyclic 3',5'-AMP accumulation in the guinea pig, 60% in the cat, and 90% in the human heart particles. Half-maximal activity for the histamine mediated activation of adenyl cyclase in the guinea pig was 9 x 10(-6)moles/liter, almost identical with that observed for norepinephrine in the same preparation. DL-Propranolol, 1 x 10(-5)moles/liter, did not abolish the activation of adenyl cyclase produced by histamine but did abolish the activation produced by norepinephrine. In contrast, diphenhydramine hydrochloride, Benadryl, 8 x 10(-5)moles/liter, abolished the activation of adenyl cyclase by histamine but not that produced by norepinephrine. These data suggest that there are at least two receptor sites in guinea pig heart mediating the activation of adenyl cyclase, one responsive to histamine, the other to norepinephrine. In addition, combined maximal doses of histamine and norepinephrine produced completely additive effects on the activation of adenyl cyclase, which suggests that at least two separate adenyl cyclase systems are present in the heart, each responsive to one of these hormones. However, definitive proof would require physical separation of the two enzymes.
Effect of reserpine on the increase in myocardial adenyl cyclase activity produced by thyroid hormone.
Explore the source record for details and available documents.
[New possibilities of statistical evaluation of autopsy records. Computer free text analysis].
Explore the source record for details and available documents.
[Automatic documentation and statistical evaluation of pathological and anatomical diagnosis reports].
Explore the source record for details and available documents.
Protein synthesis in relation to ripening of pome fruits.
Protein synthesis by intact Bartlett pear fruits was studied with ripening as measured by flesh softening, chlorophyll degradation, respiration, ethylene synthesis, and malic enzyme activity. Protein synthesis is required for normal ripening, and the proteins synthesized early in the ripening process are, in fact, enzymes required for ripening. (14)C-Phenylalanine is differentially incorporated into fruit proteins separated by acrylamide gel electrophoresis of pome fruits taken at successive ripening stages. Capacity for malic enzyme synthesis increases during the early stage of ripening. Fruit ripening and ethylene synthesis are inhibited when protein synthesis is blocked by treatment with cycloheximide at the early-climacteric stage. Cycloheximide became less effective as the climacteric developed. Ethylene did not overcome inhibition of ripening by cycloheximide. The respiratory climacteric is not inhibited by cycloheximide. It is concluded that normal ripening of pome fruits is a highly coordinated process of biochemical differentiation involving directed protein synthesis.
Primary glomangioma of the liver: imaging findings.
Glomus organs are small arteriovenous anastomoses that are chiefly responsible for thermoregulation of the distal portion of the extremities. Glomangiomas are benign tumors of these bodies. Glomangiomas occur preferentially in the fingers and toes, but some case reports have described primary glomangiomas in the respiratory or gastrointestinal tract and the genitals. To date, no glomangiomas of the liver have been observed. We report on a 61-year-old patient in whom routine ultrasound disclosed a subcapsular well-defined mass in the liver. On imaging studies, no correspondence to the usual liver tumors was found. Magnetic resonance-guided biopsy showed a primary glomangioma of the liver. Clinically, the patient had no appetite and lost weight over several months. Due to the patient's weight loss and potential malignant transformation, the tumor was excised. Histologic work-up confirmed the diagnosis of a glomangioma with no signs of malignancy.
Resourceful management of esophageal food impaction.
Explore the source record for details and available documents.
Thyroid hormone therapy in cardiovascular disease.
The relationship between thyroid disease states and cardiovascular hemodynamics is well recognized. Although the long-term effects of thyroid hormone are thought to result from changes in myocardial gene expression, attention has recently focused on acute, non-nuclear-mediated actions of L-triidothyronine (T3), the biologically active form of the hormone. Various lines of evidence have documented that T3 can act as a vasodilator and inotrope. With this recognition have come novel treatment strategies targeted at specific clinical conditions including heart failure and cardiac surgery that are associated with impaired cardiovascular performance and low serum T3 levels. An understanding of the mechanisms of action of thyroid hormone on the heart and peripheral vasculature is essential for the rational implementation of thyroid hormone as a therapeutic agent. As outlined in this review, initial clinical experience suggests that the ability of thyroid hormone to increase cardiac output and to lower systemic vascular resistance may provide a novel treatment option for physicians caring for patients with cardiovascular illness.
Cellular basis of long-term rat liver allograft acceptance: role of donor and recipient leukocyte persistence in rat liver grafts.
Explore the source record for details and available documents.
Resolution of abnormal muscle enzyme studies in hypothyroidism.
Serum levels of muscle enzymes including creatine phosphokinase (CPK) have been reported to be abnormal in hypothyroidism. Seven patients with increased thyroid stimulating hormone (TSH) and elevated CPK levels were followed during replacement by oral l-thyroxine or l-thyroxine plus triiodothyronine. Data in three patients demonstrate a fairly constant rate of fall in CPK with a half-time for disappearance of approximately ten to 12 days. The normalization of muscle enzymes often precedes the correction of elevations in TSH.
The effect of intraarticular injection of morphine and bupivacaine on postarthroscopic pain control.
This study sought to compare the effects of morphine, bupivacaine, and saline injected into the knee after arthroscopic surgery. In a double-blind, randomized trial, 124 patients received either bupivacaine, morphine, bupivacaine and morphine, or saline at the completion of surgery. Postoperative pain was assessed with a 100-mm visual analog pain scale. Analgesic requirements were calculated, and weightbearing status was recorded. We found that morphine alone injected intraarticularly at the completion of arthroscopic knee surgery had no significant effect on postoperative pain, need for supplemental analgesia, or weightbearing status. Patients receiving morphine in combination with bupivacaine did not demonstrate any statistically significant improvement over those receiving bupivacaine alone. Therefore, our results failed to show any beneficial effect of morphine used for postoperative analgesia, either alone or in combination with bupivacaine. The overall pattern in all patients demonstrated decreased pain scores, decreased analgesic use, and increased weightbearing status as the observation period progressed. Finally, preoperative pain was correlated with pain at discharge, indicating that the most significant predictor of postoperative pain was preoperative level of discomfort.
Mixed acid-base disturbances in diabetes. Recognition and terminology.
Explore the source record for details and available documents.