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1.  Sustained release of carmustine (BCNU) for treatment of experimental intraocular malignancy. 
Sustained release of carmustine (1,3-bis[2-chloroethyl]-1-nitrosourea, or BCNU) via an episcleral implanted silicone device was used to treat Greene hamster melanoma implanted in the anterior chamber of rabbit eyes. Group 1 animals received carmustine intravenously; group 2 received the drug by local sustained release via an episcleral implanted silicone device; group 3 received the drug by both local sustained release and intravenous injection (a total dosage more than twice that in group 1); and group 4 was not treated. The effectiveness of the various administration routes was compared by clinical observation of tumour size and systemic and local toxic reactions, and by histopathological examination. Carmustine delayed the growth of Greene melanoma in all 3 treated groups, but was most effective when a lower dose of the drug administered intravenously was combined with an additional higher dose administered by local sustained release. Local side effects included corneal clouding and conjunctival oedema and congestion at the early stage of local drug delivery via the episcleral implanted device.
PMCID: PMC1040098  PMID: 6860615
2.  Should Lumbar Puncture Be Routinely Performed in Patients With Suspected Bacteremia? 
In an attempt to develop a rational basis for performing lumbar puncture in sepsis workups, the hypothesis was tested that, for each of eight variables with a known association with bacteremia, the frequencies for patients having bacterial meningitis would be significantly greater than those in patients having bacteremia alone. In a one-year period, 168 lumbar punctures were performed in children having a mean age of 7.3 months. Patients were assigned to four groups: bacterial meningitis, bacteremia only, aseptic meningitis, and normal. Mean age, frequencies of symptoms, clinical appearances, ethnic groups, and sex ratio were determined for all groups. Frequencies of eight variables were determined and compared between Groups I and II.
Results indicated that frequencies were not significantly different for groups I and II and that lethargy and petechiae, although distinguishing between groups I and IV, did not distinguish among the three groups having serious disease. It was concluded that since one cannot distinguish among groups having serious disease, all such patients suspected of sepsis should undergo lumbar puncture.
PMCID: PMC2561725  PMID: 6655717
3.  Development and characterization of monoclonal antibodies to Marek's disease tumor-associated surface antigen. 
Infection and Immunity  1983;41(2):851-854.
Four monoclonal antibodies, A35, B94, EB29, and G152, against Marek's disease tumor-associated surface antigen have been developed and their specificities studied against a panel of Marek's disease and lymphoid leukosis primary tumors; Marek's disease, and lymphoid leukosis, and reticuloendotheliosis lymphoblastoid cell lines; and normal chicken cells. A35 and G152 are of the immunoglobulin M class, and B94 and EB29 are of the immunoglobulin G1 subclass.
PMCID: PMC264721  PMID: 6874076
4.  Induction of plasma protein secretion in a newly established human hepatoma cell line. 
Molecular and Cellular Biology  1983;3(6):1133-1137.
To study the expression and the regulation of hepatocyte markers, we have undertaken to establish human hepatoma cell lines of various phenotypes. We now report the establishment of a new human hepatoma cell line, HA22T/VGH. This cell line has many of the properties of human hepatocellular carcinoma. Only 5 of 15 plasma proteins investigated were detected in the medium of a 10-day-old HA22T/VGH culture. However, when the HA22T/VGH cells and a clonal derivative, C5, were cultured in an aggregated form, all 15 plasma proteins were found in the culture medium. These results indicate that hepatoma cell lines with different phenotypes can be established, and they provide a good experimental framework to investigate differentiation of human hepatocytes.
PMCID: PMC368642  PMID: 6683778
5.  Metabolic alkalosis in the rat. Evidence that reduced glomerular filtration rather than enhanced tubular bicarbonate reabsorption is responsible for maintaining the alkalotic state. 
Journal of Clinical Investigation  1983;71(5):1141-1160.
Maintenance of chronic metabolic alkalosis might occur by a reduction in glomerular filtration rate (GFR) without increased bicarbonate reabsorption or, alternatively, by augmentation of bicarbonate reabsorption with a normal GFR. To differentiate these possibilities, free-flow micropuncture was performed in alkalotic Munich-Wistar rats with a glomerular ultrafiltrate total CO2 concentration of 46.5 +/- 0.9 mM (vs. 27.7 +/- 0.9 mM in controls). Alkalotic animals had a markedly reduced single nephron GFR compared with controls (27.4 +/- 1.5 vs. 51.6 +/- 1.6 nl/min) and consequently unchanged filtered load of bicarbonate. Absolute proximal bicarbonate reabsorption in alkalotic animals was similar to controls (981 +/- 49 vs. 1,081 +/- 57 pmol/min), despite a higher luminal bicarbonate concentration, contracted extracellular volume, and potassium depletion. When single nephron GFR during alkalosis was increased toward normal by isohydric volume expansion or in another group by isotonic bicarbonate loading, absolute proximal bicarbonate reabsorption was not substantially augmented and bicarbonaturia developed. To confirm that a fall in GFR occurs during metabolic alkalosis, additional clearance studies were performed. Awake rats were studied before and after induction of metabolic alkalosis associated with varying amounts of potassium and chloride depletion. In all cases, the rise in blood bicarbonate concentration was inversely proportional to a reduction in GFR; filtered bicarbonate load remained normal. In conclusion, a reduction in GFR is proposed as being critical for maintaining chronic metabolic alkalosis in the rat. Constancy of the filtered bicarbonate load allows normal rates of renal bicarbonate reabsorption to maintain the alkalotic state.
PMCID: PMC436975  PMID: 6853706
6.  Comparison of cytochromes from anaerobically and aerobically grown cells of Pseudomonas perfectomarinus. 
Journal of Bacteriology  1983;154(1):278-286.
Pseudomonas perfectomarinus (ATCC 14405) is a facultative anaerobe capable of either oxygen respiration or anaerobic nitrate respiration, i.e., denitrification. A comparative study of the electron transfer components of cells revealed five c-type cytochromes and cytochrome cd in the soluble fraction from anaerobically grown cells and four c-type cytochromes in the soluble fraction from aerobically grown cells. Purification procedures yielded three c-type cytochromes (designated c-551, c-554, and acidic c-type) from both kinds of cells as indicated by similarities in absorption spectra, molecular weight, and electrophoretic mobility. Cytochrome cd, a diheme c-type cytochrome (cytochrome c-552), and a split-alpha c-type cytochrome were recovered only from anaerobically grown cells. A c-type cytochrome with a low ratio of alpha to beta absorption peak heights was uniquely present in the aerobically grown cells. Liquid N2 temperature absorption spectroscopy on the membrane fraction from anaerobically grown cells revealed residual cytochrome cd as well as differences in the relative amounts of c-type and b-type cytochromes in membranes prepared from cells grown under the two different conditions.
PMCID: PMC217457  PMID: 6833178
7.  Production of Epoxides from α,β-Halohydrins by Flavobacterium sp 
The relative activity of Flavobacterium whole cells on the enzymatic synthesis of epoxides from α,β-chlorohydrins, -bromohydrins, and -iodohydrins is described.
PMCID: PMC242423  PMID: 16346235
8.  Premonitory symptoms of stroke in evolution to the locked-in state. 
Three patients, who subsequently developed the locked-in state characterised by quadriplegia and mutism with an alert sensorium, initially had mild dysarthria and uncrossed hemisensory or hemimotor deficits involving the face and ipsilateral extremities. Case one initially mimicked a left cerebral lesion with right hemisensory deficits, a mild right facial paresis and a right homonymous field deficit. Case two initially developed both left hemimotor and hemisensory deficits and later developed a paresis of right conjugate gaze. Case three presented with left hemimotor deficit, and mild paresis of conjugate gaze to the right. All three patients died. Rostral brainstem infarctions were found at necropsy in cases one and two. Case three had a radiolucent area of the brainstem demonstrated by CT Scan. Hemisensory and hemimotor deficits also have been noted to precede reported cases of pontine infarction with the locked-in state. Acute onset of uncrossed hemisensory and hemimotor deficits with dysarthria may be caused by infarction of the pons which may predispose to the locked-in state.
PMCID: PMC1027328  PMID: 6842229
9.  Plasmid-directed synthesis of hepatitis B surface antigen in monkey cells. 
We introduced the gene encoding the hepatitis B virus surface antigen (HBsAg) into simian virus 40 (SV40)-based plasmids capable of autonomously replicating in both Escherichia coli and permissive monkey cells. After introduction into monkey cells by transfection, these plasmids directed the synthesis of high levels of HBsAg, as determined by immunofluorescence, radioimmunoassays, and identification by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the polypeptides comprising the antigen. Expression was dependent upon the presence of an SV40 promoter, with both the early and late promoters able to effectively initiate transcription. Using expression of HBsAg to assay promoter function, we demonstrated that an intact copy of the SV40 72-base pair repeat, which constitutes an essential element of the SV40 early promoter during the lytic SV40 cycle and which can enhance the transcriptional activity of heterologous promoters, was not required for HBsAg expression, suggesting that the hepatitis genome contains an enhancer element capable of complementing that provided by the 72-base pair repeat element of SV40. The antigen appears to be glycosylated after synthesis in transfected cells and is apparently secreted, as evidenced by the localization of [35S]cysteine-labeled antigen to the medium of transfected cultures. Using constructions in which the first ATG sequence appearing in HBsAg mRNA was that corresponding to the gene encoding the mature form of the antigen, we demonstrated that these post-translational events could occur without the involvement of a putative precursor peptide suggested by the DNA sequence of the viral genome. In view of the inability of hepatitis B virus to propagate in vitro, this strategy offers a convenient approach for further characterizing the biosynthesis of this antigen and may provide a means to identify additional polypeptides encoded by this virus.
PMCID: PMC368501  PMID: 6298607
10.  Association of eukaryotic DNA topoisomerase I with nucleosomes and chromosomal proteins. 
Nucleic Acids Research  1983;11(2):461-472.
A DNA topoisomerase activity is found to be associated with the nucleosomes released by the Staphylococcal nuclease digestion of HeLa nuclei. Such an association is found to be salt dependent. A number of criteria have established that this DNA topoisomerase activity is due to HeLa topo I (Liu, L. F. and Miller, K. G. (1980) Proc. Natl. Acad. Sci. USA 78, 3489-3491). A similar association has been demonstrated from the in vitro studies using purified mononucleosomes and eukaryotic DNA topoisomerase I. Nonhistone HMG proteins and histone H1 are found to stimulate topoisomerase activity in vitro and form tight complexes with eukaryotic DNA topoisomerase I. The intimate interactions of topoisomerase I with chromosomal proteins and nucleosomes may be an essential feature of the topoisomerase function in vivo.
PMCID: PMC325725  PMID: 6298726
11.  Expression of hepatitis B virus surface antigen in yeast. 
Nucleic Acids Research  1983;11(9):2745-2763.
The structural gene of Hepatitis B virus surface protein (HBsAg) was introduced into a plasmid capable of autonomous replication and selection in both the yeast Saccharomyces cerevisiae and E. coli. In this plasmid transcription of the HBsAg is initiated by the 5'-flanking sequence of the yeast 3-phosphoglycerate kinase (PGK) gene and terminated by the 3'-flanking region of the yeast TRP1 gene. Yeast cells containing this plasmid produce a new major species of mRNA of 1200 nucleotides in length coding for HBsAg. Viral surface antigen is made in nonglycosylated form at a level of about 1-2 percent of total yeast protein. A small fraction of this polypeptide (2-5 percent) is found in aggregated form upon yeast cell disruption by glass beads. This material is similar in size, density, and shape to the 22nm particle, isolated from the plasma of human hepatitis carriers, and induced comparable levels of HBsAg antibodies in mice when compared with the natural particle.
PMCID: PMC325921  PMID: 6344021

Results 1-11 (11)