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At least 217 records · Page 12Linked to original sources
PubMed1975

Syndrome and pancreatic disease, subcutaneous fat necrosis and polyserositis. Case report and review of literature.

Immunologic evaluation of a patient with pancreatitis, subcutaneous fat necrosis, pleuritis, pericarditis and synovitis is presented. The previously recognized syndrome of pancreatic disease, subcutaneous fat necrosis and arthritis is reviewed. Based on analysis of all the cases described in the English language literature it is suggested that this syndrome be expanded to include polyserositis rather than arthritis alone. Although experimental and clinical evidence tends to implicate physiocochemical tissue injury by pancreatic lipase as the primary pathogenic mechanism in this syndrome, studies in our patient suggest the possible contribution of immune-mediated injury. Supporting data include eosinophilia, biopsy demonstration of vasculitis antedating the subcutaneous fat necrosis, immunofluorescent identification of immunoglobulin G (IgG) and C3 in the pleura, and reduced levels of total hemolytic complement in the serum, and pleural and pericardial effusions.

Adipose Tissue↗
PubMed1984

The development of the human interradicular dentine as revealed by tetracycline-labelling.

The pattern of labelling of the interradicular dentine that forms the floor of the pulp chamber was studied in human deciduous second mandibular molars from patients who had undergone treatment with tetracycline during the period of formation of those teeth. Six teeth exhibited isolated mineralization centres for the interradicular dentine, indicating that this region in man, unlike in rodents, does not develop as a direct continuation of coronal dentine.

Dental Pulp Cavity↗
PubMed1994

A technique for the isolation and purification of viable mucosal mast cells/globule leukocytes from the small intestine of parasitised sheep.

Romney sheep, 1-2 years old, immunized by at least three anthelmintic abbreviated infections of 80-100,000 Trichostrongylus colubriformis larvae usually produced high numbers of intestinal mucosal mast cells/globule leukocytes (MMC/GLs). In isolating these cells, the importance of maintaining the intestine at 37 degrees C, removal of mucus with dithiothreitol, enzymatic dispersion and careful in vitro handling procedures for maximising cell viability are emphasised. The MMC/GLs were separated from most contaminant cells by using a Percoll discontinuous gradient. MMC/GLs collected at the 60/100% Percoll interface were passed through a complement coated nylon wood column to remove the contaminating eosinophils. Viable MMC/GLs were able to grow in vitro in the presence of Concanavalin A and survive in culture for up to 30 days. The MMC/GLs were readily identified by ultraviolet light microscopy after staining with auramine O.

Animals↗
PubMed1983

A simple micromethod for leukocyte rosetting without cell purification.

Conventional methods for leukocyte rosetting suffer from 2 major drawbacks: the length of time required for leukocyte purification prior to rosetting, and the necessity for large volumes of blood from which to purify the leukocytes. A simple method for leukocyte rosetting is described which uses small quantities (less than 100 microliter) of heparinized whole blood, does not require prior leukocyte purification and can be completed within 1 h of blood drawing. Percentages of rosetting polymorphonuclear leukocytes in cell preparations obtained by standard purification methods showed a close correlation (P less than 0.001) with percentages obtained by the method described. Additionally, the method described can potentially be applied to other non-neutrophil rosetting leukocytes in blood or body fluids.

Cell Separation↗
PubMed1988

Enumeration of IFN-gamma-producing cells by flow cytometry. Comparison with fluorescence microscopy.

A new intracytoplasmic immunofluorescence staining to detect and quantify human interferon-gamma (IFN-gamma)-producing cells by means of flow cytometry is described. Mononuclear leukocytes, stimulated in vitro to produce IFN-gamma, were fixed and made permeable to antibodies by sequential exposure to paraformaldehyde and the detergent n-octyl-glucoside. Cytoplasmic IFN-gamma was demonstrated by indirect immunofluorescence using IFN-gamma-specific mouse monoclonal antibodies. The staining exhibited a very characteristic morphology and was localized in the Golgi apparatus. An excellent agreement between the enumeration of cytoplasmic IFN-gamma-positive cells by immunofluorescence microscopy and flow cytometry was noted. However, the latter has the advantage of a standardized control, is less labor consuming and is observer independent.

Adult↗
PubMed1996

The use of the lipophilic fluorochrome CM-DiI for tracking the migration of lymphocytes.

In this study we examined the new cell dye CM-DiI for tracking the migration of lymphocytes from blood to lymph. This lipophilic marker intercalates in the plasma membrane like the PKH dyes and older DiI derivatives. The stability and intensity of staining achieved with these dyes is better than most other fluorochromes or radioisotopes, yet they are poorly soluble in aqueous solutions, which can make staining difficult, and they are not fixable in tissue sections. CM-DiI is reported to have increased water solubility and it can be fixed using traditional aldehyde fixatives, making it feasible to detect labeled cells in histological sections. To determine the suitability of CM-DiI as a lymphocyte marker, a labeling protocol was developed. We tested the ability of stained cells to recirculate in vivo. Following the intravenous injection of CM-DiI positive cells, their recovery in lymph over 40 h was comparable to that of cells labeled with other fluorochromes or radioisotopes. The kinetics of recirculation were also very similar, as labeled cells were detectable in lymph within 4 h of injection, and the peak percentage of labeled cells in lymph was generally observed between 20-30 h. We also confirmed that CM-DiI is retained in the lymphocyte membrane following routine paraffin processing. Thus CM-DiI does not appear to alter the process of lymphocyte recirculation, and it should be a useful marker for tracking these cells.

Animals↗
PubMed1991

Dislocation of chromatin elements in prophase induced by diethylstilbestrol: a novel mechanism by which micronuclei can arise.

The in vitro micronucleus test with Syrian hamster embryo (SHE) cells assays the induction of micronuclei by chemical agents. Both chromosome fragments and lagging chromosomes can give rise to micronuclei. Nevertheless, only limited information is available on the ultrastructure of micronuclei and the mechanisms of their formation. Diethylstilbestrol (DES), a non-mutagenic carcinogen, as well as its analogue 3.3'-DES induce micronuclei in SHE cells. A comparison of the dose response of DES-induced micronucleus formation with the previously published ones for aneuploidy and transformation shows that all 3 run in parallel. Thus, a functional relationship between these endpoints, in the SHE system, may be implied. The present study is designed to address the formation of micronuclei using supravital UV microscopy, to test for the presence of defined chromosome domains within micronuclei using immunocytochemistry, and to define aspects of their ultrastructure by electron microscopy. Supravital UV microscopy showed that 3.3'-DES induces displacement of chromosomes/chromatids during prophase/anaphase and formation of micronuclei during cytokinesis. Immunocytochemistry revealed that micronuclei contain, at high frequencies, CREST antibody-reactive kinetochores, indicating the presence of whole chromosomes or centric fragments in these structures. Moreover, transmission electron microscopy showed that micronuclei exhibit ultrastructural details typical of interphase nuclei. Specifically, micronuclei exhibited morphological evidence of a nuclear lamina and segregation of karyoplasm into euchromatic and heterochromatic regions. All micronuclei examined were enclosed by a nuclear envelope of normal morphology and showed nuclear pore complexes. Together the findings provide evidence that DES interferes with the mitotic apparatus as early as prophase, resulting in the formation of micronuclei and, as a consequence, in the loss of chromatids or chromosomes.

4-Nitroquinoline-1-oxide↗
PubMed1994

A UV laser-scanning confocal microscope for the measurement of intracellular Ca2+.

Modifications to the optics of a conventional confocal laser-scanning microscope were made to allow imaging intracellular Ca(2+)-dependent fluorescence with a UV laser (351 or 364 nm). Modifications included: (1) a chromatic compensation lens in the laser path; (2) the design of a practically achromatic relay lens; (3) a longer tube length for the objective; and (4) highly reflective mirrors maximizing fluorescence measurement. This UV laser-scanning confocal microscope (UV-CLSM) yielded a lateral resolution of < 0.3 micron and an axial resolution of < 1.5 microns and a relevant field size of 100 microns in diameter for a 40X objective). The effects of varying the focal length of a compensation lens, the degree of the correction for the coverglass thickness of objective and the detector aperture size on the quality of image formation were examined. Finally, UV-CLSM revealed optical sections of fine and complex structures of bullfrog sympathetic neurones loaded with a Ca(2+)-sensitive fluorescent probe. Changes in intracellular free Ca2+ distribution in response to high [K+] or caffeine were demonstrated. In addition, an increase in the intracellular concentration of caffeine applied externally was clearly imaged in space and time and distinguished from a resultant rise in [Ca2+]i. Thus, the UV-CLSM developed is suitable for ratiometric intracellular Ca2+ measurements and other biological studies.

Animals↗
PubMed1993

Cell-cycle dependent micronucleus formation and mitotic disturbances induced by 5-azacytidine in mammalian cells.

5-Azacytidine was originally developed to treat human myelogenous leukemia. However, interest in this compound has expanded because of reports of its ability to affect cell differentiation and to alter eukaryotic gene expression. In an ongoing attempt to understand the biochemical effects of this compound, we examined the effects of 5-azacytidine on mitosis and on micronucleus formation in mammalian cells. In L5178Y mouse cells, 5-azacytidine induced micronuclei at concentrations at which we and others have already reported its mutagenicity at the tk locus. Using CREST staining and C-banding studies, we showed that the induced micronuclei contained mostly chromosomal fragments although some may have contained whole chromosomes. By incorporating BrdU into the DNA of SHE cells, we determined that micronuclei were induced only when the compound was added while the cells were in S phase. Microscopically visible effects due to 5-azacytidine treatment were not observed until anaphase of the mitosis following treatment or thereafter. 5-Azacytidine did not induce micronuclei via interference with formation of the metaphase chromosome arrangement in mitosis, a common mechanism leading to aneuploidy. Supravital UV microscopy revealed that chromatid bridges were observed in anaphase and, in some cases, were sustained into interphase. In the first mitosis after 5-azacytidine treatment we observed that many cells were unable to perform anaphase separation. All of these observations indicate that 5-azacytidine is predominantly a clastogen through its incorporation into DNA.

Anaphase↗
PubMed2004

Antimitotic activity of glaupalol-related coumarins from Glaucidium palmatum.

Two new coumarins, glaumacidines A (1) and B (2), and the related coumarins (3-7) have been isolated from the rhizomes of Glaucidium palmatum (Glaucidiaceae). The absolute configurations of 1 and 2 and trans- and cis-glaupadiols (3 and 4, respectively) were elucidated by spectroscopic data, chemical derivatization, and exciton chirality method. Glaupalol (5) enhanced the polymerization of tubulin and affected synergistically with paclitaxel on inhibition of KB cell proliferation.

Antineoplastic Agents↗
PubMed2004

Bayesian framework for the evaluation of fiber evidence in a double murder--a case report.

Fiber evidence found on a suspect vehicle was the only useful trace to reconstruct the dynamics of the transportation of two corpses. Optical microscopy, UV-Vis microspectrophotometry and infrared analysis were employed to compare fibers recovered in the trunk of a car to those of the blankets composing the wrapping in which the victims had been hidden. A "pseudo-1:1" taping permitted to reconstruct the spatial distribution of the traces and to further strengthen the support to one of the hypotheses. The Likelihood Ratio (LR) was calculated, in order to quantify the support given by forensic evidence to the explanations proposed. A generalization of the Likelihood Ratio equation to cases analogous to this has been derived. Fibers were the only traces that helped in the corroboration of the crime scenario, being absent any DNA, fingerprints and ballistic evidence.

Automobiles↗
PubMed2004

Acylated flavonoids and phenol glycosides from Veronica thymoides subsp. pseudocinerea.

A new acylated flavone glucoside, 3'-hydroxyscutellarein 7-O-(6''-O-protocatechuoyl)-beta-glucopyranoside (1), and a new phenol glucoside, 3,5-dihydroxyphenethyl alcohol 3-O-beta-glucopyranoside (6) were isolated from Veronica thymoides subsp. pseudocinerea together with seven known flavone, phenol and lignan glycosides; 3'-hydroxyscutellarein 7-O-(6''-O-trans-feruloyl)-beta-glucopyranoside (2), 3'-hydroxy, 6-O-methylscutellarein 7-O-beta-glucopyranoside (3), luteolin 7-O-beta-glucopyranoside (4), isoscutellarein 7-O-(6'''-O-acetyl)-beta-allopyranosyl (1''' --> 2'')-beta-glucopyranoside (5), 3,4-dihydroxyphenethyl alcohol 8-O-beta-glucopyranoside (7), benzyl alcohol 7-O-beta-xylopyranosyl (1" --> 2')-beta-glucopyranoside (8), and (+)-syringaresinol 4'-O-beta-glucopyranoside (9). Compounds 2, 3 and 7-9 were reported for the first time in the genus Veronica. The structures of the isolates were determined by means of spectroscopic (UV, IR, 1D and 2D NMR, HR ESI-MS) methods. Isolated compounds (1-7) exhibited potent radical scavenging activity against the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical.

Acetylation↗
PubMed2004

Xanthones from a microfungus of the genus Xylaria.

Chemical investigations of a microfungus Xylaria sp. isolated from the Australian rainforest tree Glochidion ferdinandi have afforded two new natural products, 2-hydroxy-6-methyl-8-methoxy-9-oxo-9H-xanthene-1-carboxylic acid (1) and 2-hydroxy-6-hydroxymethyl-8-methoxy-9-oxo-9H-xanthene-1-carboxylic acid (2). Compound 1 has previously been synthesised but only partially characterised. Methylation of 1 using diazomethane afforded the crystalline compound 2,8-dimethoxy-6-methyl-9-oxo-9H-xanthene-1-carboxylic acid methyl ester (3), whose structure was determined by single crystal X-ray analysis. This paper reports the full spectroscopic characterisation of compounds 1-3 by NMR, UV, IR and MS data. All compounds were inactive in a brine shrimp lethality assay and several antimicrobial screens.

Ascomycota↗
PubMed2006

Diffuse interstellar bands: a comprehensive laboratory study.

As a result of the search for the identity of the chromophores responsible for producing the diffuse interstellar bands, a comprehensive exposition of experimental data is presented, which implicates the following molecules: (1) The extremely stable organic molecules, magnesium tetrabenzoporphyrin (MgTBP) and H(2)TBP. (2) A paraffin matrix (referred to as "grains") containing TBPs. (3) A low concentration of pyridine (also within the grains), whose transmission window at 2175 A, accounts for the ubiquitous UV bump. The blue emission spectra associated with the central star, HD44179, of the Red Rectangle displays the fluorescence excitation spectra of bare MgTBP. This unique spectrum matches the low temperature lab data of MgTBP in the vapor phase. An effective grain temperature of 2.728 K (+/-0.008) was deduced, based on MgTBP's lowest measured vibrational state of 341 GHz.

Astronomical Phenomena↗