Discovery of ONO-8590580: A novel, potent and selective GABAA α5 negative allosteric modulator for the treatment of cognitive disorders.

The identification and SAR development of a series of negative allosteric modulators of the GABAA α5 receptor is described. This novel series of compounds was optimised to provide analogues with high GABAA α5 binding affinity, high α5 negative allosteric modulatory activity, good functional subtype selectivity and low microsomal turnover, culminating in identification of ONO-8590580.

Distributed communication and psychosocial performance in simulated space dwelling groups.

The present report describes the development and application of a distributed interactive multi-person simulation in a computer-generated planetary environment as an experimental test bed for modeling the human performance effects of variations in the types of communication modes available, and in the types of stress and incentive conditions underlying the completion of mission goals. The results demonstrated a high degree of interchangeability between communication modes(audio, text) when one mode was not available. Additionally, the addition of time pressure stress to complete tasks resulted in a reduction in performance effectiveness, and these performance reductions were ameliorated via the introduction of positive incentives contingent upon improved performances. The results obtained confirmed that cooperative and productive psychosocial interactions can be maintained between individually isolated and dispersed members of simulated spaceflight crews communicating and problem-solving effectively over extended time intervals without the benefit of one another's physical presence.

Effects of platelet-derived growth factor isoforms on calcium release from neonatal mouse calvariae.

Platelet-derived growth factor (PDGF) is the major growth factor in serum for cells of mesenchymal origin and induces many different activities, including bone resorption. Since the initial report that PDGF stimulated calcium release from bone organ cultures, it has been shown that PDGF is a dimeric protein consisting of two disulfide bonded polypeptides encoded by different genes. Three isoforms of the two gene products have been isolated. We compared the capacity of each isoform to stimulate calcium release from radiolabeled mouse calvariae. PDGF-AB from human platelets and recombinant PDGF-BB isoforms significantly stimulated calcium release at 5 ng/ml, but not in lower doses. Recombinant PDGF-AA did not induce calcium release. Indomethacin blocked the stimulated bone resorption, suggesting a prostaglandin-mediated mechanism of action. PDGF-induced calcium release was compared to TGF-beta 1 in the organ culture system. Approximately a 10-fold greater concentration of PDGF-AB and PDGF-BB was required to achieve a similar degree of calcium release as found in TGF-beta 1 treated calvariae. Thus, TGF-beta 1, PDGF-AB, and PDGF-BB significantly stimulated calcium release from mouse calvariae. This response is specific in that PDGF-AA did not stimulate calcium release.

Tuberculosis treatment delivery in Bali: a qualitative study of clinic staff perceptions.

SETTING: Little is known about the challenges of delivering tuberculosis (TB) treatment in Indonesia's southern province of Bali. OBJECTIVE: We aimed to explore staff perceptions of TB treatment delivery and barriers to improved TB control in Bali to inform strategies for programme development. DESIGN: Semi-structured interviews were conducted with staff who were involved in the delivery of TB treatment services in the public sector. RESULTS: The main issues perceived by staff to influence TB treatment delivery include: the low level of community awareness of TB; delays to treatment seeking and the frequent use of private treatment providers; diagnostic difficulties; non-adherence to treatment; and a low level of staff education specific to TB. CONCLUSION: Staff perceived a number of significant barriers to the early diagnosis and successful treatment of TB in Bali. The development of strategies to address these identified difficulties in TB control is essential to support improved programme effectiveness and enhanced TB control in Bali.

Mitogenic effects of growth factors on human periodontal ligament cells in vitro.

Periodontal regeneration is thought to require the migration and proliferation of periodontal ligament cells. Evidence suggests that the polypeptide growth factors PDGF, IL-1, and TGF-beta are mediators of these cellular events in wound healing. The purpose of this study was to determine the effects of these growth factors on human periodontal ligament (PDL) cell mitogenesis, and to identify the regulatory influences of TGF-beta on the response to PDGF and IL-1. Confluent, quiescent human PDL cells were cultured in vitro and treated with the polypeptide growth factors PDGF-AA and -BB, IL-1 beta, and TGF-beta in both a dose and time-dependent manner. Mitogenic activity, as a measure of proliferative potential, was determined by the quantitation of 3H-thymidine incorporation during DNA synthesis. The results of this study demonstrated that both PDGF-AA and -BB enhance mitogenic activity in a dose-dependent manner over a concentration range of 1.0 to 50.0 ng/ml. IL-1 beta (0.01 to 1.0 pM) resulted in no mitogenic enhancement, and at high concentrations (10.0 to 100.0 pM) demonstrated an inhibitory effect. TGF-beta produced a significant increase (P < 0.01) in mitogenic activity (although relatively much less than PDGF) in a delayed, bimodal, dose-dependent manner over a concentration range of 0.01 to 20.0 ng/ml, with a maximal response at a concentration of 1.0 ng/ml. Additionally, incubation with TGF-beta at 1.0 ng/ml prior to the addition of PDGF significantly enhanced (P < 0.01) the mitogenic response to both PDGF-AA and PDGF-BB.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of conditioned medium from connective tissue fibroblasts and epithelium on calcium release from mouse calvarial organ culture.

Fibroblasts from periodontal ligament and gingival explants were cultured in vitro. The conditioned media from four different periodontal ligament and four gingival explant cultures were examined to determine their effect on calcium release in mouse calvarial organ culture. All the cultures stimulated calcium release, with a range of 20.6-43% over control. Conditioned media from two periodontal ligament cultures and a gingival culture significantly stimulated calcium release from the bone organ culture. The stimulatory activity in the oral fibroblasts cell cultures was compared to that in conditioned medium from two non-oral, established, fibroblasts cell lines and an epidermal keratinocyte cell line. Similar to the oral fibroblast cultures, conditioned medium from all three cell lines resulted in stimulation of calcium release in the bone culture assay. In order to characterize the bone-stimulating activity, a 0.4 micron membrane was used to separate the cell cultures from the bone organ culture. Both gingival and periodontal ligament fibroblast cultures gave values for calcium release significantly less than control when the separating membrane was used. Both non-oral cell lines and the epidermal keratinocyte cell line gave values for calcium release similar to those when no membrane was used. These results suggest that oral fibroblasts, but not non-oral fibroblasts and epidermal keratinocytes, release a unique bone-resorption stimulating activity.

The induction of specific metabolic alterations in mouse calvarial organ cultures by glycosaminoglycans.

Glycosaminoglycans specifically regulate the amount of calcium released from bone cultures; the mechanisms responsible for this regulation are not known. Media from glycosaminoglycan-stimulated bone organ cultures were analysed to determine (1) if specific calcium-releasing substances were selectively produced, and (2) if protein synthesis was differentially affected by glycosaminoglycans. Chondroitin sulphate B, hyaluronic acid and keratan sulphate at 100 micrograms/ml significantly increased prostaglandin release when compared with control cultures. In combination with suboptimal concentrations of PTH, chondroitin sulphate B, heparin and keratan sulphate significantly stimulated prostaglandin release. When indomethacin was included in the test assays, the stimulated prostaglandin release was abolished. Heparin-treated cultures released the greatest percentage of latent collagenase activity followed by hyaluronic acid-treated cultures. Organ cultures treated with heparin and PTH amount of active collagenase. Stimulation increased interleukin-1 above control levels but with no significant difference among the glycosaminoglycans except for keratan sulphate cultures with which had the greatest amount of interleukin-1. Collagen protein decreased between 48 and 72 h under both control and experimental conditions. Examination of the predominant [35S]-methionine labelled proteins revealed that prostaglandin E2 treatment resulted in a relative shift in labelling to higher molecular-weight proteins as time in culture increased (up to 144 h). After 48 h, when equal amounts of labelled protein were analysed, there was a predominance in labelling of a 200,000 Da protein in the prostaglandin-treated cultures. These findings demonstrate that modulation of calcium release by glycosaminoglycans results in the selective release of molecules capable of stimulating calcium release.(ABSTRACT TRUNCATED AT 250 WORDS)

Permeability of demineralized dentin to HEMA.

OBJECTIVES: The objectives of this study were to develop a macromodel of the demineralized layer of dentin that is formed after acid-etching, and to determine if the amount of HEMA uptake was responsive to air drying. The hypothesis that was tested was that HEMA uptake by demineralized dentin depends upon the degree of expansion of the collagen fibril network. METHODS: Dentin cubes (2 x 2 x 2 mm) were prepared in coronal dentin from extracted unerupted human third molars. They were incubated in 100% HEMA for up to 1000 min and then removed and blotted free of excess adherent HEMA. The HEMA taken up by each cube was extracted in 2 ml of water for 1 hr with shaking. This was repeated and the extracts combined. HEMA was quantitated spectrophometrically. The dentin cubes were then demineralized in 0.5 M EDTA for 10 days and the HEMA uptake remeasured at 1, 10, 100 and 1000 min. Then the cubes were air-dried and the HEMA uptake remeasured. After re-expanding the specimens in water, the cubes were stiffened in ascending concentrations of acetone of 100%, then allowed to air dry again in a more expanded state, and HEMA uptake was remeasured. Finally, after rehydration, the dentin cubes were "acid-etched" for 1 or 10 min with 37 wt% phosphoric acid and HEMA uptake remeasured. RESULTS: Before demineralization, the dentin took up little HEMA (ca. 4.8 x 10(-7) moles min-3) compared to after demineralization when the uptake for 10, 100 and 1000 min was 27.4, 43.8 and 51.4 x 10(-3) moles mm-3, respectively. Acid etching for 1 or 10 min had no effect on HEMA uptake. Air drying produced a 72% volumetric shrinkage but a 97% reduction in uptake. When the demineralized matrix was stiffened in acetone prior to air-drying, the volumetric shrinkage was only 27% and the HEMA uptake only fell 16% compared to the wet, fully expanded condition. SIGNIFICANCE: The results support the hypothesis that the uptake of HEMA by demineralized dentin depends on the degree of expansion of the dentin matrix.

Survey of current practice patterns for percutaneous transluminal coronary angioplasty. SANDBAG Nursing Coordinators.

BACKGROUND: The increasing complexity of coronary intervention has led to variations in current patterns of nursing practice for patients undergoing routine percutaneous transluminal coronary angioplasty. In preparation for a large study examining the effects of specific nursing practices on complications at the site of vascular access, we surveyed institutions participating in a randomized phase III trial involving 4010 patients to determine current patterns of practice. OBJECTIVE: The purpose of this study was to determine the current patterns of nursing practice for patients undergoing percutaneous transluminal coronary angioplasty. METHODS: An eight-page questionnaire was completed by 70 hospitals participating in the study titled Integrelin to Manage Platelet Aggregation to Prevent Coronary Thrombosis (IMPACT II). RESULTS: The hospitals participating in this study have an average of 500 beds; 34% of the institutions do 500 to 1000 angioplasty procedures annually. At many sites (39%), heparin is infused for 12 to 18 hours after the intervention, but heparin is not infused at all in 31% of the hospitals studied. At 27% of the hospitals, arterial sheaths are removed 12 to 18 hours after angioplasty, and at 15% of the hospitals, sheaths are removed more than 18 hours after the procedure. Typically after angioplasty (36%), patients are transferred to an ICU, with a nurse-patient ratio of 1:2. Eighty-three percent of the hospitals use CareMAPs or care plans for standardization of care. Most hospitals (83%) require complete bed rest for patients who have had angioplasty, with the affected leg restrained to prevent mobility. Ninety-one percent of the hospitals reported continuing to treat the patient with bed rest for an additional 6 hours after the sheath is removed. CONCLUSION: Comprehensive nursing standards of care based on well-designed clinical trials for patients after angioplasty are not available. In the second phase of our study, we hope to correlate nursing practices with clinical outcome data to improve further the care of patients who have had angioplasty.

Nursing interventions to decrease bleeding at the femoral access site after percutaneous coronary intervention. SANDBAG Nursing Coordinators. Standards of Angioplasty Nursing Techniques to Diminish Bleeding Around the Groin.

BACKGROUND: This trial is the first prospective, multicenter clinical nursing trial conducted to measure the effect of nursing interventions on bleeding at the femoral access site after percutaneous coronary intervention with or without a potent antiplatelet agent given along with heparin and aspirin. OBJECTIVE: To measure the relationship between nursing interventions and complications at the arterial access site in patients undergoing percutaneous coronary interventions and to recommend a standard of care to minimize bleeding complications. METHODS: In a descriptive, correlational 4010-patient study, nursing care interventions after coronary procedures were measured. Observed standards of care were assessed, and regression techniques were used to evaluate nursing interventions and the effect of the interventions on bleeding at the access site after percutaneous coronary procedures. RESULTS: Several significant correlations between nursing interventions and the occurrences of moderate to severe bleeding at the access site were found; however, most interventions had little effect. The most significant factors in decreasing complications at the access site were early removal of the arterial sheath, the type of pressure mechanism used to achieve arterial hemostasis, staffing allocation, and the person and method used to remove the sheath. CONCLUSION: Many nursing interventions after percutaneous coronary intervention have become routine in the absence of clinical outcome data. Most nursing interventions aimed at decreasing bleeding at the vascular access site increase nursing workload but do not significantly affect bleeding in the groin. These results underscore the importance of continued clinical research studies to validate nursing practice on the basis of patients' outcomes.

Optical disguising of orbital deformity with prism and cylinder lenses.

This paper describes the way in which prism and cylinder lenses may be used to disguise orbital dystopia when the affected eye is blind. The lenses used can correct the height of the eye, the opening of the eyelids or the rotation or slant of the eye. Four cases are presented to illustrated this technique, which may be used either instead of, or as an adjunct to orbital surgery. An investigation of these effects is described using a mannikin head fitted with an optician's trial frame, with measuring by the reflex metrograph. This revealed that an inferiorly displaced eye may be elevated by 4 to 5 mm, that the vertical eyelid opening may be widened (or narrowed) by just under 20% and that an adverse slant of the eye may be rotated in either direction by about 4 degrees.

Sustained nonischemic ventricular tachycardia during dobutamine stress echocardiography.

Dobutamine stress echocardiography has become widely accepted as a safe, reliable and cost effective modality for the evaluation of patients with suspected myocardial ischemia or for prognostic stratification and outcome assessment in patients with known coronary artery disease. while the benefits of this means of cardiovascular testing are very clearly apparent, it is important to understand and recognize possible complications. This paper discusses the occurrence of sustained, nonischemic ventricular tachycardia during dobutamine stress echocardiography in the absence of functional, physiologic or anatomic evidence of coronary artery disease or cardiomyopathy.

Development of a new, more sensitive immunoassay for human tryptase: use in systemic anaphylaxis.

Tryptase, a neutral protease, is selectively concentrated in the secretory granules of human mast cells, and its release into the circulation serves as a clinical marker of mast cell activation. The current study describes a new, more sensitive ELISA utilizing a newly developed, mouse monoclonal IgG1 antibody for capture called B12 and capable of detecting tryptase in normal plasma and serum. The greater sensitivity of the new immunoassay results in part from a greater portion of tryptase being detected. Mean levels of tryptase in serum from normal subjects from Richmond, Virginia (4.9 ng/ml; n = 56), Munich, Germany (3.8 ng/ml; n = 19), and Amersfoort, The Netherlands (1.9 ng/ml; n = 8) were as indicated. In 62 subjects with ongoing allergic rhinitis, tryptase levels were no different in serum than for 19 normal controls, indicating that local mast cell activation is not necessarily reflected in the circulation. In 61 subjects sensitive to honey bee or yellow jacket venom by history, the 17 destined to have a severe, hypotensive response to a sting challenge had higher levels of tryptase at baseline than mild reactors, nonreactors, and controls, suggesting that baseline levels of tryptase may predict the severity of the clinical response to allergen in sensitive subjects.