Search PubMed⌕ Search

Biomedical subjects

T C Hall

Publications and source records attributed to T C Hall.

At least 127 records · Page 7Linked to original sources
PubMed1977

Breast cancer: lack of prognostic value of adrenal pathology at adrenalectomy.

The adrenal glands of 58 patients undergoing adrenalectomy for advanced breast cancer were reviewed and correlated with subsequent course of the patients' disease. Three patients had thecomatous metaplasia in the adrenal cortex, six patients had myelolipomatous changes, and 13 patients had metastatic breast cancer in their adrenal glands at the time of adrenalectomy. Neither the presence of metastases nor myelolipomatous changes were associated with a long disease-free interval, a long period from mastectomy to adrenalectomy, or a prolonged postadrenalectomy survival. The patients with metastatic breast cancer in the adrenal glands had more widespread disease than patients without adrenal metastases. The presence of breast cancer metastases in the adrenal glands at the time adrenalectomy identifies patients further advanced in the course of their disease, but is not related prognostically to the effect of adrenalectomy.

Adrenal Gland Neoplasms↗
PubMed1977

Case reports and studies of paraneoplastic hypotension: abnormal low pressure baroreceptor responses.

Intrathoracic stretch receptors regulate adjustments of the vasculature to gravitational changes and influence urinary water and solute excretion. Few reports of pathologic states involving interruption of these regulatory mechanisms have appeared. Two patients with orthostatic hypotenstion related to advanced intrathoracic carcinoma were studied, utilizing tilt-table examinations and immersion of the entire body in water to test the function of their intrathoracic baroreceptor reflex arcs. Both patients showed abnormalities of antidiuretic hormone level and sodium excretion as compared with normal controls. This suggests that total immersion is a safe and convenient test of the low-pressure baroreceptor system in patients with suspected dysfunction. Three patients are also reported whose charts were reviewed posthumously. Although they were not tested in the laboratory, their clinical data suggest that they too had been suffering from an interference with the transmission of impulses from the intrathoracic receptors.

Adult↗
PubMed1977

Loss of infectivity of brome mosaic virus RNA after chemical modification of the 3' or 5' terminus.

Brome mosaic virus (BMV) RNA that had both termini chemically modified by periodate oxidation and aniline-catalyzed cleavage of the terminal nucleotide had drastically reduced infectivity. BMV RNA that was first enzymatically tyrosylated to protect the 3' terminus from modification, and then modified at the 5' terminus by periodate oxidation and aniline cleavage, had a similar reduction in infectivity. Tyrosylation followed by acetylation modifies only the 3' terminus. Nevertheless, acetylated tyrosyl-BMV RNA was less than one-fourth as infectious as a control sample subjected to procedures that differed only by the presence of tyrosinol (which prevents aminoacylation and subsequent acetylation). For each modified form of viral RNA, care was taken to test the infectivity of appropriate control samples. The integrity of the modified RNAs was examined by gel electrophoresis and by biological translation and aminoacylation assays. We conclude that, in different ways, both the 5'- and 3'-terminal structures of BMV RNA play important roles during infection of the host.

Base Sequence↗
PubMed1977

Equal Expression of the Maternal and Paternal Alleles for the Polypeptide Subunits of the Major Storage Protein of the Bean Phaseolus vulgaris L.

Discontinuous sodium dodecyl sulfate slab gel electrophoresis of G1 globulin from several strains of Phaseolus vulgaris L. seed permitted clear resolution of the constituent polypeptides. Three strains (Tendergreen, Canadian Wonder, and BBL 240) had subunits of molecular weight 53,000, 47,000 and 43,000 while two strains (Seafarer and PI 229,815) had 50,500, 47,000 and 43,000 molecular weight subunits. F(1) seed from the cross BBL 240 x PI 229,815 showed four polypeptides on dissociation of the G1 protein; however, the amount of each of the 53,000 and 50,500 subunits was half that of the 47,000 subunit. This is interpreted as evidence that both the maternal and paternal loci for these polypeptides are transcribed and translated with similar efficiency. All of the polypeptides were found to have associated sugar residues.

Journal Article↗
PubMed1976

Late effects of cancer therapy: the role of the clinical pharmacologist.

The clinical pharmacologist, by increasing our knowledge of the molecular mode of action of drugs and their specific anticancer mechanisms, can help to predict which therapies would be expected to have late effects that were progeric, infectious, or oncogenic, and in which organs such effects could arise. By insisting upon the inclusion of appropriate controls, the pharmacologist can help attribute any observed late effects to a primary host-disease diathesis, or to the direct effects of therapy, or to the indirect effects of prolongation of the life of the host. Finally, by participating in the design and including appropriate control groups from the start of new clinical trials, the clinical pharmacologist can help restrict clinical therapies whose antitumor effects are absent or small but whose late toxic potentials are high.

Antineoplastic Agents↗
PubMed1976

Differential Localization of Fraction I Protein between Chloroplast Types.

The soluble proteins of C(3) and C(4) mesophyll chloroplasts and C(4) bundle sheath extracts have been analyzed by gel electrophoresis for fraction I protein. Gel scans of soluble protein from C(4) bundle sheath extracts and C(3) mesophyll chloroplasts showed typical fraction I protein peaks that could be identified by ribulose diphosphate carboxylase activity. No such peak was observed for C(4) mesophyll chloroplasts, which also lacked both large and small subunits of ribulose diphosphate carboxylase on sodium dodecyl sulfate gels. The absence of fraction I protein in these chloroplasts was reflected in the soluble protein to chlorophyll ratios, which were roughly 3-fold lower than the ratio obtained for C(3) chloroplasts. The carboxylating enzyme in C(4) mesophyll cells, phosphoenolpyruvate carboxylase, was found to be a major protein in the cytoplasm of C(4) mesophyll protoplasts, and had higher mobility than fraction I protein.

Journal Article↗
PubMed1976

Affinity Chromatography of the Major Seed Protein of the Bean (Phaseolus vulgaris L.).

The major globulin of the French bean (Phaseolus vulgaris L.) undergoes a reversible pH-dependent polymerization. At pH values above 6.5, the monomeric form of the protein predominates; and at pH values below 6.5, the protein occurs as a polymer, probably a tetramer. At extremes of pH, the protein dissociates further into peptides. The reversible pH-dependent interaction between globulin subunits is used in this report as the basis for an affinity chromatography procedure for isolation of the globulin. The major globulin from several genetic variants can be obtained in gram quantities and does not indicate the presence of any impurities on discontinuous sodium dodecyl sulfate gel electrophoresis.

Journal Article↗
PubMed1976

Interaction of elongation factor 1 with aminoacylated brome mosaic virus and tRNA's.

Tyrosylated Brome mosaic virus RNA was found to interact with a binary complex of wheat germ, elongation factor 1 and [3H]GTP. Increasing amounts of the aminoacylated viral RNA proportionately reduced radioactivity bound to a nitrocellulose filter, as has previously been noted by others for the charged forms of tobacco mosaic virus, turnip yellow mosaic virus, and tRNA's. However, Sephadex chromatography of the products showed that instead of forming the ternary complex elongation factor-GTP-aminoacyl RNA, the viral RNA caused release of GTP from its complex with elongation factor. Acetylated tyrosyl Brome mosaic virus RNA did not react with the binary complex,and only a slight degree, if any, of stabilization of tyrosine bound to viral RNA was observed after interaction with elongation factor 1. Although such interactions are similar to the reaction of elongation factor with aminoacyl-tRNA , the release of GTP is different and accentuates the possible role for aminoacylation in transcription rather than in translation events.

Guanosine Triphosphate↗
PubMed1976

Functional possibilities for aminoacylation of viral RNA in transcription and translation.

RNA from at least ten viruses, representing more than four different group, is known to specifically bind in amino acid in a tRNA-like manner. The biological function of aminoacylation of RNA from these viruses and of tRNA association with tumor viruses and bacteriophage, is discussed. Hypothetical schemes are presented for a role for aminoacylation in viral translational and transcriptional mechanisms, and the current evidence relating to these models is presented.

Amino Acids↗
PubMed1975

Clinical studies of 5-fluorouracil + premarin in the treatment of breast cancer.

Sixty patients with metastatic or primary inoperable breast cancer not suitable for hormone alteration therapy were blindly randomized between weekly 5-fluorouracil, intravenously, and daily physiologic doses of conjugated estrogens by mouth against weekly 5-fluorouracil, intravenously, and placebo. There was no difference in the survival or the effect on the tumor in the two groups. Numerous factors were analyzed as to their effect on the course of the disease. The number of organ sites of tumor involvement, age of the host, and previous treatment for the disseminated disease were not shown to influence the survival or the results of therapy of either group. However, the duration of the clinical cancer-free period from primary treatment to recurrence, the sites of organ involvement, and the performance status of the patients at the time of entry into the study significantly did influence the survival. There is no evidence in this study that physiologic doses of conjugated estrogens deleteriously influenced the course of the disease.

Adult↗
PubMed1975

Heritable Variation in a Polypeptide Subunit of the Major Storage Protein of the Bean, Phaseolus vulgaris L.

Electrophoretic analysis of the major seed protein, G1 globulin, from four strains of Phaseolus vulgaris L. revealed a three-banded pattern for two strains having a high methionine content (BBL 240 and PI 302,542). The other two strains (PI 207,227 and PI 229,815) known to have a lower seed methionine content, had a two-banded subunit pattern for the G1 globulin. Analytical ultracentrifugation confirmed that globulin from the two-banded strains underwent pH-dependent reversible dissociation similar to that previously found for a three-banded cultivar; additionally, the protomer molecular weight showed that three subunits of about 50,000 molecular weight each were present in the G1 globulin of the two-banded strain. Gel patterns of G1 globulin from the two strains used as parents, BBL 240 and PI 229,815, showed differences in the largest subunit, which appeared as either a 53,000 molecular weight polypeptide known to be present in the three-banded strain, or as a shorter polypeptide having a molecular weight close to 47,000. Analysis of G1 protein from portions of single hybrid seeds showed a banding pattern intermediate between the two- and three-banded types. The subunit pattern from all seeds with intermediate-banded parents segregated in a manner consistent with that expected for control of the polypeptide by a single Mendelian gene. The remaining portions of the seeds were grown to confirm that they represented true crosses. The procedures used are essentially nondestructive, and can be used as a basis for selecting seeds having different protein characters.

Journal Article↗
PubMed1975

Cell-free Synthesis of the Major Storage Protein of the Bean, Phaseolus vulgaris L.

As seeds of the French bean (Phaseolus vulgaris, L. cv. Tendergreen) mature, a single protein, G1 globulin (analogous to legumin), represents the majority of protein synthesized. Washed polysomes extracted from developing cotyledons had little endogenous activity in amino acid incorporation, but on addition of cell-free extracts from wheat germ, active incorporation was obtained, the level being similar to that with viral RNA as messenger. The Mg(2+) optimum for protein synthesis in the presence of bean polysomes was 6 mm compared with 4 mm for synthesis of viral polypeptides in the wheat germ system. Using T-2 toxin as an inhibitor, it was shown that 29% of the incorporation depended on initiation events. Electrophoretic analysis of the total polypeptide products of cell-free synthesis gave a disperse profile. Centrifugation to remove polysome-bound peptides after 60 minutes incubation gave a supernatant having a product with the same electrophoretic mobility as G1 globulin and containing 26% of the radioactivity present in the gel. Protein eluted from this peak was subjected to re-electrophoresis and shown to consist of the three polypeptide subunits characteristic of G1 globulin.

Journal Article↗