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Biomedical subjects

J R Carter

Publications and source records attributed to J R Carter.

At least 127 records · Page 7Linked to original sources
PubMed1968

Cytidine triphosphate: phosphatidic acid cytidyltransferase in Escherichia coli.

An enzyme has been found in particulate fractions of Escherichia coli that catalyzes the incorporation of cytidine triphosphate (CTP) into lipid in the presence of exogenous phosphatidic acid and Mg(++). The product has been identified enzymatically and by chromatography as cytidine diphosphate diglyceride. The reaction is optimal at a pH of 6.5 and Mg(++) concentration of 5-10 mm. The apparent K(m) for CTP is 7 x 10(-4)M and for phosphatidic acid, 2 x 10(-3)M. The reaction rate falls off rapidly with time and ceases entirely after 1 hr as the result of inactivation of the system by Mg(++).

Cytosine Nucleotides↗
PubMed1966

Membrane structure and function.

An understanding of the biochemical basis of membrane function is an important goal of present day biology. In this paper, a biochemical approach to the problem of the specific transport of sugars across the membrane of Escherichia coli is discussed. A new biochemical model for lactose transport system in this organism is presented, in which a specific membrane protein (M protein) plays the role of the sugar carrier. Experiments which have led to the discovery of such a protein, its specific labeling, and partial purification are briefly reviewed.

Carbon Isotopes↗
PubMed1966

Enzymatic synthesis of cytidine diphosphate diglyceride.

Evidence is presented for the enzymatic formation of cytidine diphosphate diglyceride in microsomal preparations from guinea pig liver according to the reaction: CTP + phosphatidic acid right harpoon over left harpoon CDP-diglyceride + p-O-P. Conditions have been found in which the incorporation of labeled CTP into CDP-diglyceride is almost entirely dependent upon added phosphatidic acid. The incorporation of CMP into lipid is very slight. A substantial net synthesis of CDP-diglyceride takes place under these conditions. Some properties of the enzyme system are described.

Animals↗
PubMedDate not supplied

Metastatic skeletal disease in the pediatric population.

We reviewed the autopsy, clinical, and radiographic records of 39 patients with metastatic skeletal disease (age range 18 months-20 years). There were 11 different primary tumors responsible for skeletal metastases, of which neuroblastoma was the most common (16 patients). Other commonly occurring tumors giving rise to secondary skeletal deposits were rhabdomyosarcoma (seven), teratoma-teratocarcinoma (four), and Wilms tumor (three). Overall patient survival ranged from 2 weeks to 72 months, with an average of 10.2 months. Those patients presenting without skeletal metastases at the time of diagnosis of the primary tumor had a survival time averaging 16.2 months (range 3-72 months), whereas those patients presenting initially with skeletal metastases at the time of diagnosis of the primary tumor had a survival time of 8.5 months (range 0.5-23 months).

Adolescent↗
PubMedDate not supplied

Late-onset tibia vara: a histopathologic analysis. A comparative evaluation with infantile tibia vara and slipped capital femoral epiphysis.

Histopathologic and histochemical studies were performed on the entire physes and contiguous structures of five knees (three patients) with late-onset tibia vara (Blount's disease). A constellation of abnormalities of both medial and lateral physeal components resulted in disorganization and misalignment of the physeal zones. The changes were remarkably similar to those observed in both infantile tibia vara and slipped capital femoral epiphysis, suggesting a common etiology. Our evaluation indicates that asymmetric compressive and shear forces acting across the proximal tibial physis effect its disruption and causes suppression and deviation of normal endochondral ossification, thereby resulting in tibia vara.

Adolescent↗
PubMedDate not supplied

Eosinophilic granuloma of bone in the growing epiphysis.

Eosinophilic granuloma of bone is a rare skeletal manifestation of one of the spectrum of diseases known as histiocytosis X. These lesions often simulate other pathophysiologic processes (Ewing sarcoma, chronic osteomyelitis, Brodie abscess, and chondroblastoma) and may present significant diagnostic problems. Three additional cases of eosinophilic granuloma in an epiphysis are reviewed in this report. Transphyseal extension was present in all our cases and in five of 10 cases documented in the literature. Diagnosis demands accurate biopsy and histopathologic evaluation. Treatment and prognosis are individualized.

Biopsy↗