35 research outputs found
International genome-wide meta-analysis identifies new primary biliary cirrhosis risk loci and targetable pathogenic pathways.
Primary biliary cirrhosis (PBC) is a classical autoimmune liver disease for which effective immunomodulatory therapy is lacking. Here we perform meta-analyses of discovery data sets from genome-wide association studies of European subjects (n=2,764 cases and 10,475 controls) followed by validation genotyping in an independent cohort (n=3,716 cases and 4,261 controls). We discover and validate six previously unknown risk loci for PBC (Pcombined<5 Ă 10(-8)) and used pathway analysis to identify JAK-STAT/IL12/IL27 signalling and cytokine-cytokine pathways, for which relevant therapies exist
Effects of Preparation and Fixation on Three Quantitative Fluorescent Cytochemical Procedures
A series of experiments was undertaken in which cells dissociated from the abdominal lymph nodes of mice were lightly centrifuged into slides and fixed either wet or after drying in 70% ethanol, 1% glutaraldehyde, 1% formaldehyde, or neutral formalin. Three fluorescent cytochemical methods were evaluated: staining of DNA with mithramycin; fluorochroming of basic groups of proteins with brilliant sulfaflavine (BSF); and staining of sulfhydryl and disulfide groups with N-(7-dimethylamino-4-methylcoumarinyl)maleimide (DACM). In the case of mithramycin, the best results were obtained after fixation in 70% ethanol without drying. Staining of dried preparations fixed in 1% glutaraldehyde also yielded reasonably consistent results, although the fluorescence was lower, and the variability higher, than in the group fixed without drying in 70% ethanol. The use of fixatives containing formaldehyde resulted in fluorescence values of only about onethird those of the other two groups, and the variability of the data was higher. In material stained with BSF, satisfactory results were obtained in preparations fixed without drying in neutral formalin containing mersalyl acid. Other fixatives could be used, but the resulting coefficients of variation were higher than those of formalin-fixed material. Sulfhydryl to disulfide ratios approaching those expected from biochemical evidence were obtained in DACM-stained material only after fixation without drying in neutral formalin containing mersalyl acid. Inverted sulfhydryl-disulfide ratios were observed in material fixed without drying in 70% ethanol; and in dried metarial fixed in 1% formaldehyde, neutral formalin, or 1% glutaraldehyde
Demonstration of Sulfhydryl and Disulfide Groups by a Fluorescent Maleimide Procedure
Several fluorescent maleimide compounds were evaluated as possible substitutes for N-(4-aminophenyl)maleimide in the histochemical procedures developed by Sippel (1973, 1978a, b, 1980) for the demonstration of sulfhydryl and disulfide groups. The brightest and most selective fluorescence was obtained by using N-(7-dimethylamino-4-methylcoumarinyl)maleimide (DACM), although both eosin-5-maleimide and fluorescein-5-maleimide could also be used if adequate control preparations were made
Ultrastructure and Histochemistry of the Supportive Structures Associated With the Radula of the Slug, Limax Maximus
The odontophore and connective tissueâfilled portion of the radular sac (called the âcollostyleâ) of the slug, Limax maximus, were examined by light and electron microscopy. While both of these structures grossly resemble vertebrate cartilage, neither is composed of a type of tissue with the microscopic appearance and histochemical properties of cartilage. The roughly Uâshaped odontophore possesses a thin capsule composed of connective tissue. The parenchyma of the odontophore consists of modified muscle cells which are organized into irregular groups by incomplete trabeculae composed of conventional muscle cells. The odontophoral cells are variable in size; they contain glycogenâfilled âcoresâ as well as bundles of peripherally located filaments resembling myofilaments; and they are innervated like muscle cells. The nuclei of the cells are located eccentrically in the glycogenâfilled portions of the cells and typically contain prominent nucleoli. The nuclei are surrounded by multiple small Golgi complexes and pleomorphic dense bodies resembling lysosomes. The extracellular matrix of the odontophore is very sparse and contains glycogen and fibrillar material but no histochemically demonstrable acidic mucosubstances. The collostyle consists of a gelatinous type of tissue somewhat like vertebrate mucoid connective tissue. The abundant extracellular matrix contains cross banded filaments, a flocculent material disposed in wavy indefinite strands, and small electronâdense particles. The matrix contains histochemically demonstrable neutral and weakly acidic mucosubstances. The cell population of the collostyle includes solitary muscle cells and fibrocytes containing large quantities of glycogen
Histochemical and Ultrastructural Features of the Aorta of the Slug (Limax maximus)
As a part of a continuing study of unusual molluscan tissues, the âchondroidâ tissue (Hyman, \u2767) associated with the anterior and posterior aortae of the slug (Limax maximus) was examined by light and electron microscopy. Unlike the odontophoral tissue of this species (Curtis and Cowden, \u2777), the âchondroidâ tissue comprising the adventitial layer of the aorta consists of large, glycogenâfilled cells with characteristic arrays of pores in their plasma membranes resembling those of the âglobularâ cells (Rogers, \u2769; Fernandez, \u2771); âfibrocytesâ (Nicaise et al., \u2766; Baleydier et al., \u2769; Nicaise, \u2773); âBlasenzellenâ or âLeydigâ cells (Wondrak, \u2769; StangâVoss, \u2770; Buchholz et al., \u2771; StangâVoss and Staubesand, \u2771; WolburgâBuchholz, \u2772); or âporeâ cells (Sminia, \u2772; Beltz, \u2777) of other mollusks. The anterior and posterior aortae are very similar in organization, except that the anterior aorta is larger in diameter; its wall is thinner; and it lacks calcification. Both the anterior and posterior aortae possess a loosely organized (incomplete) endothelial layer surrounded by two layers of innervated smooth muscle. The smooth muscle cells possess fibrous surface specializations resembling hemidesmosomes as well as large numbers of tubular or rounded vesicles in association with their plasma membranes. Blood cells (amoebocytes) containing large glycogen deposits and distinctive membraneâenclosed cytoplasmic inclusions can be found occasionally in the walls of the vessels
A Fluorescent Water Soluable Carbodiimide-2-Hydroxy-3-Naphthoic Acid Hydrozide Reaction for the Demonstration of Carboxyl Groups in Proteins and Mucosubstances
The carbodiimide-2-hydroxy-3-naphthoic acid hydrazide reaction as developed by Geyer (1964) was used without subsequent diazonium coupling as a fluorescent method for the demonstration of carboxyl groups in both proteins and mucosubstances. The topological distribution of the fluorophore was similar to that reported by Geyer. Quantitative microfluorometric studies on cartilage sections revealed differences in detail between emissions in cartilage matrix mucoprotein as compared to the dense connective tissue associated with the perichondrium which consists principally of protein. It would also appear that the primary fluorescent emission of unstained preparations at 450 mm should be useful in microfluorometric determinations of proteins
Movement of Spermatozoa of Megaselia Scalaris (Diptera: Brachycera: Cyclorrhapha: Phoridae) in Artificial and Natural Fluids
In artificial fluid, the spermatozoa move as linear cells or round up and rotate, propelled by spontaneous bending of their tails. Both linear and rounded cells can move forward and backward, but usually they move forward. The tails of all cells display, simultaneously, small primary bends and fewer, much larger secondary bends. Rounded cells form single secondary bends that remain unchanged as the cells rotate. They also form ânodeâlikeâ primary bends that travel posteriorly or anteriorly as the cells rotate forward or backward, respectively. Linear cells move their anterior regions into and out of focus in a cyclic fashion. They form rather prominent primary bends, as well as two to four secondary bends that travel posteriorly as the cells move forward. Secondary bends change in shape continuously and are not sinusoidal. The cells follow approximately linear trajectories, but the distances traveled per cycle, speeds, and secondary bending patterns are variable. When methyl cellulose is added to artificial fluid, linear movement is improved, and forward speeds are approximately tripled. The movement of spermatozoa in natural fluid of the female reproductive tract is remarkably less stereotyped than that of cells in artificial fluid. The cells, usually resembling straight lines or arcs, are very flexible and active. They lack obvious cyclic activity and double bending patterns. They are capable of moving both forward and backward and of adjusting their bending activity and speed within rather wide limits. Their average forward speed is about nine times faster than that of cells in artificial fluid
A Comparison of Two Methods of Preparing Cells or Nuclei for High-Resolution Microspectrophotometry
Suspensions of isolated mouse thymus cells were subjected to two preparative methods: either they were dropped through several mm of 9:1 v/v ethanol-acetic acid fixative, allowed to stand for 1 hr and then processed for staining; or they were fixed, passed through a graded ethanol series to 70% ethanol, centrifuged on to slides in a modified Shandon cytocentrifuge and then carried wet into the staining procedure. All preparations were stained by the Feulgen reaction and evaluated by high-resolution microspectrophotometry. While the two preparative procedures yielded similar results, there appeared to be less variability in the data obtained from the centrifuged cell populations