Two-dimensional analysis of the redox state of the rat cerebral cortex in vivo by NADH fluorescence photography.

A photographic method for measuring two-dimensional changes in NADH fluorescence and hemoglobin distributions in the rat cerebral cortex in vivo has been developed. Intracellular NADH was excited by UV light peaking at 360 nm and the emission was observed through a window with the maximum transmission at 450 nm. The fluorescence photographs (360 leads to 450 nm) required 20-25 sec exposures at the aperture opening of f/5.6 and the reflectance photographs (360 leads to 360 nm) 10 sec exposures at f/32. The digitization of photographic images was achieved either by a PDP-8-controlled microdensitometer coupled to an A/D converter or by a combination of a manually operated microdensitometer and a computer-controlled digitizer. In the latter case, a photographic negative was scanned with a Joyce-Loebl microdensitometer in parallel lines 170 mum apart, and the densitometric tracings were digitized with a PDP-8-controlled TV digitizer. The digital data were processed by DEC PDP-10 computer and the results were displayed in 3-dimensional surfaces. Nitrogen anoxia caused increases in fluorescence at 450 nm ranging from 10 to 75% fo the normoxic fluorescence intensities (after correcting for the logarithmic characteristics of the photographic films) and decreases in reflectance intensities in the range of 10-30%. The spatial resolution of the present technique is limited to approximately 30 mum X 30 mum on the cortical surface and the time resolution to 10-25 sec. The optical properties of the cerebral cortex in vivo appear to be controlled primarily by blood vessel patterns and hemodynamic factors and secondarily by the redox state of the tissue. Evidence for a heterogeneous redox response of the cerebral cortex toward N2 anoxia was obtained.     

A pilot project in molecular cancer epidemiology: determination of benzo[a]pyrene -- DNA adducts in animal and human tissues by immunoassays

A highly-sensitive immunoassay utilizing antiserum specificfor benzo[a]pyrene covalently bound to DNA has been employedto probe for adducts in the DNA of animal and human tissuesand peripheral blood mononuclear cells. By enzyme-linked immunosorbentassay (ELISA) a dose-related increase in levels of benzo[a]pyrene—DNAadducts was observed in DNA from lung tissue of mice and rabbitsinjected i.p. with benzo[a]pyrene. Quantitation with ELISA wasconfirmed by i.p. injection of [³H]benzo[a]pyrene and determinationof adduct levels in lung DNA by radioactivity. Thus, the ELISAassay was determined to be quantitative for benzo[a]pyrene—DNAadducts in vivo, and the lower limit of detectability establishedat 0.08–0.10 fmol/µg DNA. At this level of sensitivityno significant differences were observed between DNA from peripheralblood mononuclear cells of dogs on smoke inhalation machinesand controls. In an attempt to probe for benzo[a]pyrene—DNAadducts in human subjects resulting from chronic environmentalexposure, lung tissue, lung tumor and blood samples were obtainedfrom patients hospitalized for lung cancer and other diseases.A detailed history of exposure to environmental sources of benzo[a]pyreneand to factors known to influence polycyclic aromatic hydrocarbonmetabolism was attempted for 15 patients. DNA was extractedfrom the lung tissue of 27 patients and blood cells of severalindividuals and assayed by ELISA; 5 patients appeared to havelow but measurable levels of benzo[a]pyrene—DNA adductsas determined by ELISA. All of these patients were in the lungcancer group. However, the number of subjects was too smallto draw conclusions relating exposure history to the occurrenceof hydrocarbon—DNA adducts. These preliminary resultsshould encourage further studies on the utilization of immunoassaysfor carcinogen—DNA adducts as a potential tool in epidemiologicalstudies attempting to relate biologically-effective dose ofcarcinogen to human cancer risk.     

Amitriptyline in migraine prophylaxis: Changes in pattern of attacks during a controlled clinical trial

A double-blind controlled clinical trial of crossover design was conducted in 26 volunteers suffering from migraine. Of 20 subjects who completed the trial, 16 had fewer attacks on amitriptyline than on placebo. Amitriptyline was found to have the greatest effect in reducing attacks with a short warning and in which no specific cause could be recognized. It had least effect in attacks with a long warning and recognized as due to fatigue. The drug was effective only in reducing those attacks with shorter duration and its effect was irrespective of severity. A dosage of between 10 and 60 mg, usually taken at night, was found to be adequate.     

The Release of Histamine,Heparin and Granule Protein from Rat Mast Cells Treated with Compound 48/80 in vitro

Fillion , G. M. B., S. A. Slorach and B. Uvnäs . The release of histamine, heparin and granule protein from rat mast cells treated with compound 48/80 i n vitro. Acta physiol. scand. 1970. 78. 547–560. The quantitative relationship between the release of histamine, heparin and granule protein from rat mast cells exposed to compound 48/80 in vitro has been investigated in order to clarify the mechanism of action of this releaser. A correlation was found between the three release curves. The ratio of heparin to granule protein was similar in extruded granules and granules remaining in the cell after compound 48/80 treatment. From these results we conclude that the principal mechanism of histamine release induced by this agent involves an initial extrusion of histamine-containing granules, followed by an exchange of histamine in the granules for cations in the extracellular medium.     

Sigmoidovaginal and cecovaginal fistula as a complication of peridiverticulitis: Report of eight cases

Diseases of the Colon &; Rectum -     

Significance of HDAC6 regulation via estrogen signaling for cell motility and prognosis in estrogen receptor-positive breast cancer

Histone deacetylase (HDAC) 6 is a subtype of the HDAC family; it deacetylates alpha-tubulin and increases cell motility. Here, we investigate the impact of an alteration of HDAC6 expression in estrogen receptor alpha (ER)-positive breast cancer MCF-7 cells, as we identified that HDAC6 is a novel estrogen-regulated gene. MCF-7 treated with estradiol showed increased expression of HDAC6 mRNA and protein and a four-fold increase in cell motility in a migration assay. Cell motility was increased to the same degree by stably transfecting the HDAC6 expression vector into MCF-7 cells. In both cases, the cells changed in appearance from their original round shape to an axon-extended shape, like a neuronal cell. This HDAC6 accumulation caused the deacetylation of alpha-tubulin. Either the selective estrogen receptor modulator tamoxifen (TAM) or the pure antiestrogen ICI 182,780 prevented estradiol-induced HDAC6 accumulation and deacetylation of alpha-tubulin, leading to reduced cell motility. Tubacin, an inhibitory molecule that binds to the tubulin deacetylation domain of HDAC6, also prevented estradiol-stimulated cell migration. Finally, we evaluated HDAC6 protein expression in 139 consecutively archived human breast cancer tissues by immunohistochemical staining. The prognostic analyses for these patients revealed no significant differences based on HDAC6 expression. However, subset analysis of ER-positive patients who received adjuvant treatment with TAM (n = 67) showed a statistically significant difference in relapse-free survival and overall survival in favor of the HDAC6-positive group (P < 0.02 and P < 0.05, respectively). HDAC6 expression was an independent prognostic indicator by multivariate analysis (odds ratio = 2.82, P = 0.047). These results indicate the biological significance of HDAC6 regulation via estrogen signaling.