A comprehensive study on identifying the structural and functional SNPs of human neuronal membrane glycoprotein M6A (GPM6A)

In our initial publication on this subject1) we reported results demonstrating that contrast is the most important factor in producing the high image quality required for reliable image analysis. We also listed the factors which enhance contrast in order of the experimentally determined magnitude of their effect. The two most powerful factors affecting image contrast attainable with sheet film are beam intensity and KV. At that time we had only qualitative evidence for the ranking of enhancing factors. Later we carried out the densitometric measurements which led to the results outlined below.Meaningful evaluations of the cause-effect relationships among the considerable number of variables in preparing EM negatives depend on doing things in a systematic way, varying only one parameter at a time. Unless otherwise noted, we adhered to the following procedure evolved during our comprehensive study:Philips EM-300; 30μ objective aperature; magnification 7000- 12000X, exposure time 1 second, anti-contamination device operating.

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Hexachlorobenzene toxicity in the monkey ovary: III. Ultrastructure induced by high (10 mg/kg) dose exposure

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100084958 ◽

1991 ◽

Vol 49 ◽

pp. 130-131

Author(s):

A. Singh ◽

A. Dykeman ◽

J. Jarrelf ◽

D. C. Villeneuve

Keyword(s):

Present Report ◽

Reproductive Toxicity ◽

Control Group ◽

Primate Model ◽

Human Follicular Fluid ◽

Thin Sections ◽

Cynomolgus Monkeys ◽

Cacodylate Buffer ◽

Induction Cycle ◽

Comprehensive Study

Hexachlorobenzene (HCB), a persistent and mobile organochlorine pesticide, occurs in environment. HCB has been shown to be present in human follicular fluid. An objective of the present report, which is part of a comprehensive study on reproductive toxicity of HCB, was to determine the cytologic effects of the compound on ovarian follicles in a primate model.Materials and Methods. Eight Cynomolgus monkeys were housed under controlled conditions at Animal facility of Health and Welfare, Ottawa. Animals were orally administered gelatin capsules containing HCB mixed with glucose in daily dosages of 0.0 or 10 mg/kg b.w. for 90 days; the former was the control group. On the menstrual period following completion of dosing, the monkeys underwent an induction cycle of superovulation. At necropsy, one-half of an ovary from each animal was diced into ca. 2- to 3-mm cubed specimens that were fixed by immersion in 2.5% glutaraldehyde in 0.1 M cacodylate buffer (pH 7.3). Subsequent procedures followed to obtain thin sections that were examined in a Hitachi H-7000 electron microscope have been described earlier.

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Comparison of Substructures Between Uniaxial and Biaxial Deformation in 1100-0 Aluminum

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100096989 ◽

1981 ◽

Vol 39 ◽

pp. 52-53

Author(s):

D. L. Rohr ◽

S. S. Hecker

Keyword(s):

Plastic Strain ◽

Cell Walls ◽

Room Temperature ◽

Mechanical Response ◽

Biaxial Tension ◽

Initial Deformation ◽

Uniaxial Deformation ◽

Biaxial Deformation ◽

Stress States ◽

Comprehensive Study

As part of a comprehensive study of microstructural and mechanical response of metals to uniaxial and biaxial deformations, the development of substructure in 1100 A1 has been studied over a range of plastic strain for two stress states.Specimens of 1100 aluminum annealed at 350 C were tested in uniaxial (UT) and balanced biaxial tension (BBT) at room temperature to different strain levels. The biaxial specimens were produced by the in-plane punch stretching technique. Areas of known strain levels were prepared for TEM by lapping followed by jet electropolishing. All specimens were examined in a JEOL 200B run at 150 and 200 kV within 24 to 36 hours after testing.The development of the substructure with deformation is shown in Fig. 1 for both stress states. Initial deformation produces dislocation tangles, which form cell walls by 10% uniaxial deformation, and start to recover to form subgrains by 25%. The results of several hundred measurements of cell/subgrain sizes by a linear intercept technique are presented in Table I.

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Measurement of spontaneous neuronal membrane activity by time lapse confocal microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100141238 ◽

1995 ◽

Vol 53 ◽

pp. 972-973

Author(s):

R H. Selinfreund ◽

A. H. Cornell-Bell

Keyword(s):

Membrane Potential ◽

Confocal Microscopy ◽

Patch Clamp ◽

Electrical Activity ◽

Time Lapse ◽

Neuronal Firing ◽

Neuronal Membrane ◽

Pituitary Cells ◽

Patch Clamp Recording ◽

Spontaneous Electrical Activity

Cellular electrophysiological properties are normally monitored by standard patch clamp techniques . The combination of membrane potential dyes with time-lapse laser confocal microscopy provides a more direct, least destructive rapid method for monitoring changes in neuronal electrical activity. Using membrane potential dyes we found that spontaneous action potential firing can be detected using time-lapse confocal microscopy. Initially, patch clamp recording techniques were used to verify spontaneous electrical activity in GH4\C1 pituitary cells. It was found that serum depleted cells had reduced spontaneous electrical activity. Brief exposure to the serum derived growth factor, IGF-1, reconstituted electrical activity. We have examined the possibility of developing a rapid fluorescent assay to measure neuronal activity using membrane potential dyes. This neuronal regeneration assay has been adapted to run on a confocal microscope. Quantitative fluorescence is then used to measure a compounds ability to regenerate neuronal firing.The membrane potential dye di-8-ANEPPS was selected for these experiments. Di-8- ANEPPS is internalized slowly, has a high signal to noise ratio (40:1), has a linear fluorescent response to change in voltage.

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Microvasculature and structure of hemal lymph nodes in the wall of the rabbit bladder: a vascular corrosion casting and EM study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100141743 ◽

1995 ◽

Vol 53 ◽

pp. 1074-1075

Author(s):

F.E. Hossler ◽

M.I. McKamey ◽

F.C. Monson

Keyword(s):

Lymph Nodes ◽

Light Microscopy ◽

Corrosion Casting ◽

Fixed Tissue ◽

Infusion Pressure ◽

India Ink ◽

Cacodylate Buffer ◽

Rabbit Bladder ◽

Lateral Walls ◽

Comprehensive Study

A comprehensive study of the microvasculature of the normal rabbit bladder, revealed unusual "capillary glomeruli" along the lateral walls. Here they are characterized as hemal lymph nodes using light microscopy, SEM, TEM, ink injection, and vascular casting.Bladders were perfused via a cannula placed in the abdominal aorta with either 2% glutaraldehyde in 0.1M cacodylate buffer (pH 7.4) for fixation, 10% India ink in 0.9% saline and 0.1M phosphate (pH 7.4) for vessel tracing, or resin (Mercoximethylmethacrylate: catalyst, 4:1:0.3; Ladd Research Industries) for vascular corrosion casting. Infusion pressure was 100mm Hg. Fixed tissue was sectioned from epon-araldyte resin, and stained with toluidine blue for light microscopy, and lead and uranium for TEM. Ink injected tissue was photographed directly from saline-filled bladders illuminated from below. Resin-filled tissue was macerated in 5% KOH and distilled water. Casts were critical point dried, sputter coated with goldpalladium, and examined by routine SEM at 10 KV.

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Glycoprotein Ib Has a Partial Role in Platelet-von Willebrand Factor Collagen Interaction

Thrombosis and Haemostasis ◽

10.1055/s-0038-1647026 ◽

1988 ◽

Vol 60 (02) ◽

pp. 182-187 ◽

Cited By ~ 2

Author(s):

Morio Aihara ◽

Ken Tamura ◽

Ryuko Kawarada ◽

Keizou Okawa ◽

Yutaka Yoshida

Keyword(s):

Platelet Aggregation ◽

Von Willebrand Factor ◽

Ricinus Communis ◽

Protein S ◽

Platelet Membrane ◽

Membrane Glycoprotein ◽

Normal Plasma ◽

Ricinus Communis Agglutinin ◽

Von Willebrand ◽

Willebrand Factor

SummaryThe adhesion of human fixed washed platelets (FWP) to collagen was decreased after treatment with Serratia marcescens protease (SP), which removed 95% of the glycocalicin from platelet membrane glycoprotein (GP) lb. However, the diminished adhesion of SP treated FWP to collagen could still be increased in the presence of purified von Willebrand factor (vWF). This ability of vWF to increase FWP adhesion to collagen is defined as collagen cofactor (CCo). The adhesion of FWP to collagen was not affected by a monoclonal antibody (MAb) to GP Ilb/IIIa (10E5), that inhibits ADP and collagen induced platelet aggregation. On the other hand, it was decreased by 50% by a MAb to GP lb (6D1), that inhibits ristocetin induced platelet aggregation. Adhesion of FWP in buffer to collagen was completely inhibited by Ricinus communis agglutinin I or concanavalin A, while Lens culinalis agglutinin and wheat germ agglutinin showed 50% inhibition. The FWP adhesion to collagen in the presence of vWF (normal plasma) was unaffected by MAbs to GP Ilb/IIIa (10E5, P2, HPL1) but was decreased to 32-38% by MAbs to GP lb (6D1, AN51, HPL11). A MAb to vWF (CLB-RAg 35), that inhibits ristocetin induced binding of vWF to platelets, decreased the CCo of normal plasma by 70%. The MAb, CLB-RAg 201, that inhibits the binding of vWF to collagen, completely inhibited the CCo of normal plasma. In conclusion, our data suggest that (1) GP lb has a partial role in FWP adhesion to collagen; (2) the binding of vWF to collagen is required for the expression of CCo; (3) CCo is partly mediated through GP lb; but (4) other platelet membrane protein(s) besides GP lb or GP Ilb/IIIa must also be involved in FWP-vWF-collagen interactions.

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Ristocetin and Botrocetin Involve Two Distinct Domains of von Willebrand Factor for Binding to Platelet Membrane Glycoprotein lb

Thrombosis and Haemostasis ◽

10.1055/s-0038-1647310 ◽

1990 ◽

Vol 64 (02) ◽

pp. 326-332 ◽

Cited By ~ 57

Author(s):

J P Girma ◽

Y Takahashi ◽

A Yoshioka ◽

J Diaz ◽

D Meyer

Keyword(s):

Von Willebrand Factor ◽

Synthetic Peptides ◽

Competitive Inhibition ◽

Final Concentration ◽

Binding Domain ◽

Platelet Membrane ◽

Platelet Glycoprotein ◽

Membrane Glycoprotein ◽

Von Willebrand ◽

Willebrand Factor

SummaryWe have evidence that ristocetin and botrocetin mediate binding of von Willebrand Factor (vWF) to platelet glycoprotein lb (GPIb) through two distinct domains on the vWF molecule. This was established by using monoclonal antibodies (MAbs) to vWF and synthetic peptides derived from the sequence of vWF. MAb 322 and MAb NMC/vW 4 both recognize native vWF as well as fragments containing the GPIb-binding domain of vWF, obtained with the following enzymes: trypsin (116 kDa), V-8 pro tease (Spill, 320 kDa) and V-8 protease plus subtilisin (33-28 kDa). Nevertheless, the lack of reciprocal displacement between the two MAbs in experiments of competitive inhibition for binding to vWF demonstrate that their respective epitopes are separate. Both MAbs inhibit 125I-vWF binding to platelet membrane GPIb and vWF-dependent platelet agglutination induced by ristocetin. However, only MAb NMC/vW4 inhibits these functions in the presence of botrocetin and when ristocetin-induced platelet agglutination is inhibited by MAb 322, botrocetin is still able to restore the agglutination. The involvement of two distinct domains of vWF for binding to GPIb in the presence of ristocetin or botrocetin was confirmed in experiments of binding of 125I-vWF to platelets using as competitor synthetic peptides corresponding to the GPIb binding domain of vWF (Cys 474 to Pro 488 and Ser 692 to Pro 708). At a final concentration of 2.5 mM both peptides inhibit more than 90% of the binding of vWF to ristocetin-treated platelets but are unable to modify this binding in the presence of botrocetin. In conclusion our data suggest that botrocetin and ristocetin involve distinct sites on vWF for binding to GPIb.

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