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1.
Nat Nanotechnol ; 15(1): 80, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31844289

ABSTRACT

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

2.
Nat Nanotechnol ; 14(12): 1123-1128, 2019 12.
Article in English | MEDLINE | ID: mdl-31686006

ABSTRACT

Superconductivity in monolayer transition metal dichalcogenides is characterized by Ising-type pairing induced via a strong Zeeman-type spin-orbit coupling. When two transition metal dichalcogenides layers are coupled, more exotic superconducting phases emerge, which depend on the ratio of Ising-type protection and interlayer coupling strength. Here, we induce superconductivity in suspended MoS2 bilayers and unveil a coupled superconducting state with strong Ising-type spin-orbit coupling. Gating the bilayer symmetrically from both sides by ionic liquid gating varies the interlayer interaction and accesses electronic states with broken local inversion symmetry while maintaining the global inversion symmetry. We observe a strong suppression of the Ising protection that evidences a coupled superconducting state. The symmetric gating scheme not only induces superconductivity in both atomic sheets but also controls the Josephson coupling between the layers, which gives rise to a dimensional crossover in the bilayer.

3.
Eur J Pharmacol ; 431(3): 277-86, 2001 Nov 23.
Article in English | MEDLINE | ID: mdl-11730719

ABSTRACT

Elevated intraocular pressure is the primary risk factor for glaucoma. Cannabinoids interact with molecular targets in the eye and lower intraocular pressure by an unknown mechanism. The purpose of the present study was to examine eye tissues for functional cannabinoid receptors of the neuronal, CB(1) class, and an endogenous ligand, anandamide. The trabecular meshwork and ciliary processes are the primary structures of the eye that contribute to intraocular pressure and thus were our focus. Total RNA, frozen sections, cellular membranes and primary cultures of cells were prepared from both bovine and cadaveric human tissues. Using cannabinoid CB(1) receptor-specific oligodeoxynucleotide primers, cannabinoid CB(1) receptor antiserum, and cannabinoid-specific compounds (CP-55,940, WIN55,212-2 and SR-141716A), the presence of cannabinoid CB(1) receptors in ciliary processes and trabecular meshwork was determined. Using reverse transcription-polymerase chain reaction, we identified mRNA encoding cannabinoid CB(1) receptor protein in ciliary process and trabecular meshwork cells. Specific binding of anti-CB(1) immunoglobulin-G in tissue sections localized cannabinoid CB(1) receptor protein to the non-pigmented epithelial cells of the ciliary process and cells of the trabecular meshwork. While CP-55,940 and WIN55,212-2 failed to stimulate [(35)S]GTP gamma S binding in membrane preparations from trabecular meshwork and ciliary process, CP-55,940 significantly stimulated whole cell [(35)S]GTP gamma S binding by 51% over basal in ciliary process epithelial cells and 69% over basal in trabecular meshwork cells permeabilized with 5 microM digitonin (p<0.001). Specificity of agonist stimulation was verified by complete blockade with the specific cannabinoid CB(1) receptor antagonist, SR-141716A. Moreover, activation of cannabinoid CB(1) receptors by CP-55,940 resulted in a 2.3+/-0.3 and 1.7+/-0.3-fold stimulation of cAMP accumulation in trabecular meshwork and ciliary process cells, respectively (p<0.01). Lastly, anandamide was detected in human trabecular meshwork (3.08 pmol/g), ciliary process (49.42 pmol/g) and neurosensory retinal (4.48 pmol/g) tissues. These data, for the first time, demonstrate in a single study the presence of both CB(1) mRNA and protein in trabecular meshwork and ciliary processes from two different species. Activation of heterotrimeric G-proteins and stimulation of cAMP accumulation by cannabinoids in vitro suggest that their intraocular pressure-lowering effects in vivo result from activation of cannabinoid CB(1) receptors in the trabecular meshwork and increase aqueous outflow.


Subject(s)
Ciliary Body/metabolism , Receptors, Drug/metabolism , Trabecular Meshwork/metabolism , Animals , Arachidonic Acids/metabolism , Cannabinoids/antagonists & inhibitors , Cannabinoids/pharmacology , Cattle , Cell Separation , Cyclic AMP/metabolism , Cyclohexanols/pharmacology , Endocannabinoids , Fluorescent Antibody Technique , GTP-Binding Proteins/metabolism , Guanosine 5'-O-(3-Thiotriphosphate)/metabolism , Humans , Intraocular Pressure/drug effects , Ligands , Piperidines/pharmacology , Polyunsaturated Alkamides , Pyrazoles/pharmacology , RNA, Messenger/analysis , RNA, Messenger/metabolism , Receptors, Cannabinoid , Receptors, Drug/agonists , Receptors, Drug/antagonists & inhibitors , Reverse Transcriptase Polymerase Chain Reaction , Rimonabant
4.
J Ophthalmic Nurs Technol ; 18(3): 101-8; quiz 124-7, 1999.
Article in English | MEDLINE | ID: mdl-10633657

ABSTRACT

With new techniques and improved medications, anterior segment surgery has become more complex. All ophthalmic medical personnel should be aware of these different medications and their reasons for use. The bioavailability and route of administration of medications are additional areas OMP should be familiar with in order to facilitate superior eye care.


Subject(s)
Eye Diseases/drug therapy , Eye Diseases/surgery , Ophthalmologic Surgical Procedures , Anesthetics, Local/therapeutic use , Anti-Bacterial Agents/therapeutic use , Anti-Inflammatory Agents/therapeutic use , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Humans , Intraocular Pressure/drug effects , Miotics/therapeutic use , Mydriatics/therapeutic use , Steroids , Therapeutic Irrigation/methods
6.
Cancer Res ; 51(2): 476-80, 1991 Jan 15.
Article in English | MEDLINE | ID: mdl-1824681

ABSTRACT

Epidemiological and experimental studies suggest that dehydroepiandrosterone (DHEA), an adrenal cortical steroid, has chemoprotective properties. Rat colonic epithelium which had been induced to a premalignant state by the colonic carcinogen azoxymethane was used as a model for patients at high risk of colorectal carcinoma, and the efficacy of dietary DHEA for chemoprotection against tumorigenesis was evaluated. Ten-week-old male F344 rats (n = 100) were given 10 weekly s.c. injections of azoxymethane at a dose of 10 mg/kg/week. One day after the final dose of carcinogen, DHEA was added to the diet of 50 rats (0.5% DHEA chow), and the other rats were used as pair-fed controls. DHEA-fed rats lost body weight throughout the 17-week study, in contrast to their pair-fed controls. Serum DHEA in DHEA-fed rats at the end of the study was 6 times that of controls (120 +/- 30 versus 18 +/- 14 pmol/ml), and serum DHEA sulfate was 23 times that of controls (1311 +/- 13 versus 55 +/- 13 pmol/ml). Addition of DHEA to the diet produced no significant chemoprotection in our model. Tumor-related mortality was somewhat increased in DHEA-fed rats (20% versus 6% in week 16 of DHEA feeding, P not significant). The cumulative prevalence of left colonic tumors, identified by weekly colonoscopic examinations, was somewhat lower in DHEA-fed rats than in controls during weeks 10 through 13 (17% versus 33% in week 12, P not significant), but in week 14 the prevalence in DHEA-fed rats became similar to that in controls (39% versus 41%). Growth curves of autochthonous left colonic tumors, as assessed for 8 weeks by computerized image analysis of colonoscopic photographs, were similar for DHEA-fed and control rats. Prevalence, mean frequency, multiplicity, and diameter of colonic tumors at necropsy of colonoscopically negative rats in week 17 were somewhat lower in the DHEA-fed rats (e.g., prevalence of 47% versus 67%), but the differences from controls were not significant. Parameters of colonic epithelial proliferation after tritiated thymidine incorporation in DHEA-fed rats were similar to those in control rats (labeling index of 8.3 +/- 0.7% versus 8.4 +/- 0.6% in week 17), despite higher serum DHEA and DHEA sulfate levels. Our findings indicate that DHEA did not have significant postinduction chemoprotective activity against azoxymethane-induced colonic tumorigenesis in this model utilizing pair-fed controls. Further preclinical studies appear to be needed before dietary DHEA can be recommended for chemoprotection trials in patients with premalignant colorectal epithelium.


Subject(s)
Antineoplastic Agents , Colon/pathology , Colonic Neoplasms/prevention & control , Dehydroepiandrosterone/therapeutic use , Precancerous Conditions/pathology , 1,2-Dimethylhydrazine , Animals , Azoxymethane/toxicity , Carcinogens/toxicity , Colon/drug effects , Colonic Neoplasms/chemically induced , Colonic Neoplasms/pathology , Dehydroepiandrosterone/administration & dosage , Diet , Dimethylhydrazines/toxicity , Epithelium/drug effects , Epithelium/pathology , Male , Muscle, Smooth/drug effects , Muscle, Smooth/pathology , Rats , Rats, Inbred F344 , Reference Values
8.
Am J Nurs ; 87(6): 892, 1987 Jun.
Article in English | MEDLINE | ID: mdl-3647719
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