Sulfonylurea Receptors Type 1 and 2A Randomly Assemble to Form Heteromeric KATPChannels of Mixed Subunit Composition

Mitochondrial alterations were studied in 25 liver biopsies from patients with alcoholic liver disease. Of special interest were the morphologic resemblance of certain fine structural variations in mitochondria and crystalloid inclusions. Four types of alterations within mitochondria were found that seemed to relate to cytoplasmic crystalloids.Type 1 alteration consisted of localized groups of cristae, usually oriented in the long direction of the organelle (Fig. 1A). In this plane they appeared serrated at the periphery with blind endings in the matrix. Other sections revealed a system of equally-spaced diagonal lines lengthwise in the mitochondrion with cristae protruding from both ends (Fig. 1B). Profiles of this inclusion were not unlike tangential cuts of a crystalloid structure frequently seen in enlarged mitochondria described below.

Download Full-text

Evidence for a shear mechanism for the precipitation of γ-zirconium hydride in zirconium

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010011043x ◽

1978 ◽

Vol 36 (1) ◽

pp. 658-659

Author(s):

G.J.C. Carpenter

Keyword(s):

Elevated Temperature ◽

Strain Field ◽

Zirconium Hydride ◽

Zirconium Atom ◽

Atom Diffusion ◽

Solvus Temperature ◽

Hexagonal Close Packed ◽

Partial Dislocations ◽

The Face

In zirconium-hydrogen alloys, rapid cooling from an elevated temperature causes precipitation of the face-centred tetragonal (fct) phase, γZrH, in the form of needles, parallel to the close-packed <1120>zr directions (1). With low hydrogen concentrations, the hydride solvus is sufficiently low that zirconium atom diffusion cannot occur. For example, with 6 μg/g hydrogen, the solvus temperature is approximately 370 K (2), at which only the hydrogen diffuses readily. Shears are therefore necessary to produce the crystallographic transformation from hexagonal close-packed (hep) zirconium to fct hydride.The simplest mechanism for the transformation is the passage of Shockley partial dislocations having Burgers vectors (b) of the type 1/3<0110> on every second (0001)Zr plane. If the partial dislocations are in the form of loops with the same b, the crosssection of a hydride precipitate will be as shown in fig.1. A consequence of this type of transformation is that a cumulative shear, S, is produced that leads to a strain field in the surrounding zirconium matrix, as illustrated in fig.2a.

Download Full-text

Direct structure images of 30° partial dislocation cores in silicon

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126111 ◽

1987 ◽

Vol 45 ◽

pp. 242-243

Author(s):

J. C. Barry ◽

H. Alexander

Keyword(s):

Dislocation Core ◽

Preparation Technique ◽

Burgers Vector ◽

Vector Type ◽

Sample Preparation Technique ◽

Lattice Images ◽

Dislocation Core Structure ◽

Type Lattice ◽

Direct Inspection

Dislocations in silicon produced by plastic deformation are generally dissociated into partials. 60° dislocations (Burgers vector type 1/2[101]) are dissociated into 30°(Burgers vector type 1/6[211]) and 90°(Burgers vector type 1/6[112]) dislocations. The 30° partials may be either of “glide” or “shuffle” type. Lattice images of the 30° dislocation have been obtained with a JEM 100B, and with a JEM 200Cx. In the aforementioned experiments a reasonable but imperfect match was obtained with calculated images for the “glide” model. In the present experiment direct structure images of 30° dislocation cores have been obtained with a JEOL 4000EX. It is possible to deduce the 30° dislocation core structure by direct inspection of the images. Dislocations were produced by compression of single crystal Si (sample preparation technique described in Alexander et al.).

Download Full-text

Electron Microscopic investigation of crooke’s change in the pituitaries of patients with hypercorticism

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100156225 ◽

1989 ◽

Vol 47 ◽

pp. 848-849

Author(s):

E. Horvath ◽

K. Kovacs ◽

L. Stefaneanu ◽

N. Losinski

Keyword(s):

Nucleolar Organizer ◽

Microscopic Investigation ◽

Electron Microscopic Investigation ◽

Ectopic Acth Syndrome ◽

Nucleolar Organizer Regions ◽

Electron Microscopic ◽

Human Pituitary ◽

Ectopic Acth ◽

Crooke’S Hyalinization

Human pituitary corticotropins have unique morphologic markers: bundles of type-1 filaments, measuring approximately 70 A in width and representing cytokeratin. The extreme ring-like accumulation of type-1 filaments, known as Crooke's hyalinization, signals functional suppression of the corticotropins and occurs in endogenous and exogenous glucocorticoid excess, caused by ACTH-secreting pituitary adenoma, glucocorticoid secreting adrenocortical tumor, ectopic ACTH-syndrome and administration of pharmacologic doses of glucocorticoids. Cells of autonomous corticotroph adenomas usually do not show Crooke's hyalin change. A minority of these tumors, however, retains sensitivity to the negative feed-back effect of elevated blood glucocorticoid levels and display typical Crooke’s change.In the present study pituitary corticotropins in various phases of Crooke's hyalinization were investigated in patients with glucocorticoid excess of various origin, applying histology, immunocytochemistry, count of argyrophilic nucleolar organizer regions (AgNOR), and transmission electron microscopy.

Download Full-text

Multiple endocrine neoplasia type 1 presenting as rosacea

Clinical and Experimental Dermatology ◽

10.1046/j.1365-2230.1996.d01-179.x ◽

1996 ◽

Vol 21 (2) ◽

pp. 170-171

Author(s):

J.D. CREAMER ◽

S.J. WHITTAKER ◽

W.A.D. GRIFFITHS

Keyword(s):

Multiple Endocrine Neoplasia ◽

Multiple Endocrine Neoplasia Type ◽

Endocrine Neoplasia ◽

Endocrine Neoplasia Type

Download Full-text

Challenges in the Diagnostic Conceptualization of CRPS-1 (Formerly Conceptualized as RSD)

Guides Newsletter ◽

10.1001/amaguidesnewsletters.2006.marapr01 ◽

2006 ◽

Vol 11 (2) ◽

pp. 1-3, 9-12

Author(s):

Robert J. Barth ◽

Tom W. Bohr

Keyword(s):

Clinical Practice ◽

Complex Regional Pain Syndrome ◽

Somatoform Disorders ◽

International Association ◽

Pain Syndrome ◽

Somatoform Disorder ◽

Syndrome Type ◽

Previous Issue

Abstract From the previous issue, this article continues a discussion of the potentially confusing aspects of the diagnostic formulation for complex regional pain syndrome type 1 (CRPS-1) proposed by the International Association for the Study of Pain (IASP), the relevance of these issues for a proposed future protocol, and recommendations for clinical practice. IASP is working to resolve the contradictions in its approach to CRPS-1 diagnosis, but it continues to include the following criterion: “[c]ontinuing pain, which is disproportionate to any inciting event.” This language only perpetuates existing issues with current definitions, specifically the overlap between the IASP criteria for CRPS-1 and somatoform disorders, overlap with the guidelines for malingering, and self-contradiction with respect to the suggestion of injury-relatedness. The authors propose to overcome the last of these by revising the criterion: “[c]omplaints of pain in the absence of any identifiable injury that could credibly account for the complaints.” Similarly, the overlap with somatoform disorders could be reworded: “The possibility of a somatoform disorder has been thoroughly assessed, with the results of that assessment failing to produce any consistencies with a somatoform scenario.” The overlap with malingering could be addressed in this manner: “The possibility of malingering has been thoroughly assessed, with the results of that assessment failing to produce any consistencies with a malingering scenario.” The article concludes with six recommendations, and a sidebar discusses rating impairment for CRPS-1 (with explicit instructions not to use the pain chapter for this purpose).

Download Full-text