Recent advances into understanding some aspects of the structure and function of mammalian and avian lungs

Recent findings are reported about certain aspects of the structure and function of the mammalian and avian lungs that include (a) the architecture of the air capillaries (ACs) and the blood capillaries (BCs); (b) the pulmonary blood capillary circulatory dynamics; (c) the adaptive molecular, cellular, biochemical, compositional, and developmental characteristics of the surfactant system; (d) the mechanisms of the translocation of fine and ultrafine particles across the airway epithelial barrier; and (e) the particle-cell interactions in the pulmonary airways. In the lung of the Muscovy duck Cairina moschata, at least, the ACs are rotund structures that are interconnected by narrow cylindrical sections, while the BCs comprise segments that are almost as long as they are wide. In contrast to the mammalian pulmonary BCs, which are highly compliant, those of birds practically behave like rigid tubes. Diving pressure has been a very powerful directional selection force that has influenced phenotypic changes in surfactant composition and function in lungs of marine mammals. After nanosized particulates are deposited on the respiratory tract of healthy human subjects, some reach organs such as the brain with potentially serious health implications. Finally, in the mammalian lung, dendritic cells of the pulmonary airways are powerful agents in engulfing deposited particles, and in birds, macrophages and erythrocytes are ardent phagocytizing cellular agents. The morphology of the lung that allows it to perform different functions-including gas exchange, ventilation of the lung by being compliant, defense, and secretion of important pharmacological factors-is reflected in its "compromise design."

Prediction of psychosis in adolescents and young adults at high risk: results from the prospective European prediction of psychosis study

Indicated prevention is currently regarded as the most promising strategy to attenuate, delay, or even avert psychosis. Existing criteria need improvement in terms of specificity and individual risk assessment to allow for better targeted and earlier interventions.

Treatment modification in human immunodeficiency virus-infected individuals starting combination antiretroviral therapy between 2005 and 2008

Adverse effects of combination antiretroviral therapy (CART) commonly result in treatment modification and poor adherence.

Resting tremor in Parkinson disease: a negative predictor of levodopa-induced dyskinesia

It is unclear whether patients with different clinical subtypes of Parkinson disease (PD) differ in their risk of developing levodopa-induced dyskinesia (LID) and whether resting tremor is negatively correlated with this risk.

Patterns of frontobasal and frontosinal fractures in children and teenagers relative to developmental stage of the facial skeleton

To clarify the patterns of frontobasal and frontosinal fractures in children and teenagers and to analyze whether the patterns relate to developmental stage of the facial skeleton.

Periosteal Distraction Osteogenesis and Barrier Membrane Application: An Experimental Study in the Rat Calvaria

Background: Distraction of the periosteum results in the formation of new bone in the gap between the periosteum and the original bone. We postulate that the use of a barrier membrane would be beneficial for new bone formation in periosteal distraction. Methods: To selectively influence the contribution of the periosteum, a distraction plate with perforations was used alone or covered by a collagen barrier membrane. All animals were subjected to a 7-day latency period and a 10-day distraction period with a rate of 0.1 mm/day. Four animals per group with or without a barrier membrane were sacrificed at 2, 4, and 6 weeks after the end of the distraction. The height of new bone generated relative to the areas bound by the parent bone and the periosteum was determined by histomorphometric methods. Results: New bone was found in all groups. At the periphery of the distraction plate, significant differences in bone height were found between the hinge and the distraction screw for the group without barrier membrane at 2 weeks (0.39 ± 0.19 mm) compared to 4 weeks (0.84 ± 0.44 mm; P = 0.002) and 6 weeks (1.06 ± 0.39 mm; P = 0.004). Differences in maximum bone height with and without a barrier membrane were observed laterally to the distraction plate at 2 weeks (1.22 ± 0.64 versus 0.55 ± 0.14 mm; P = 0.019) and 6 weeks (1.61 ± 0.56 versus 0.73 ± 0.33 mm; P = 0.003) of the consolidation period. Conclusion: Within the limitations of the present study, the application of a barrier membrane may be considered beneficial for new bone formation induced by periosteal distraction.

Effect of enamel matrix derivative and parathyroid hormone on bone formation in standardized osseous defects: an experimental study in minipigs

Previous experimental studies have indicated that locally administered enamel matrix derivative (EMD) and parathyroid hormone (PTH) may have a stimulatory effect on bone formation. However, it is not clear if the positive effect of EMD is related to its effect on the periodontium as a whole or directly on the bone-forming cells. In addition, it is not known if the presentation of PTH by adding the amino acid sequence Arg-Gly-Asp (RGD) is essential for its osteopromotive effect. Local delivery of a bioactive substance at the right time and in the right concentration often constitutes a major challenge. Polyethylene glycol-based hydrogel (PEG) is a degradable vehicle developed for delivery of bioactive proteins. To enhance the mechanical stability of the PEG-bioactive substance complex, an osteoconductive bone substitute material is often needed.

Microbiologic results after non-surgical erbium-doped:yttrium, aluminum, and garnet laser or air-abrasive treatment of peri-implantitis: a randomized clinical trial

The purpose of this study is to assess clinical and microbiologic effects of the non-surgical treatment of peri-implantitis lesions using either an erbium-doped:yttrium, aluminum, and garnet (Er:YAG) laser or an air-abrasive subgingival polishing method.

Comparison of gingival crevicular fluid sampling methods in patients with severe chronic periodontitis

The analysis of samplings from periodontal pockets is important in the diagnosis and therapy of periodontitis. In this study, three different sampling techniques were compared to determine whether one method yielded samples suitable for the reproducible and simultaneous determination of bacterial load, cytokines, neutrophil elastase, and arginine-specific gingipains (Rgps). Rgps are an important virulence factor of Porphyromonas gingivalis, the exact concentration of which in gingival crevicular fluid (GCF) has not been quantified.

Effects of implant design on marginal bone changes around early loaded, chemically modified, sandblasted Acid-etched-surfaced implants: a histologic analysis in dogs

A minimal marginal bone loss around implants during early healing has been considered acceptable. However, the preservation of the marginal bone is related to soft tissue stability and esthetics. Implant designs and surfaces were evaluated to determine their impact on the behavior of the crestal bone. The purpose of this study is to evaluate histologic marginal bone level changes around early loaded, chemically modified, sandblasted acid-etched-surfaced implants with a machined collar (MC) or no MC (NMC).

Influence of a machined collar on crestal bone changes around titanium implants: a histometric study in the canine mandible

It has been shown that peri-implant crestal bone reactions are influenced by both a rough-smooth implant border in one-piece, non-submerged, as well as an interface (microgap [MG] between implant/abutment) in two-piece butt-joint, submerged and non-submerged implants being placed at different levels in relation to the crest of the bone. According to standard surgical procedures, the rough-smooth implant border for implants with a smooth collar should be aligned with the crest of the bone exhibiting a smooth collar adjacent to peri-implant soft tissues. No data, however, are available for implants exhibiting a sandblasted, large-grit and acid-etched (SLA) surface all the way to the top of a non-submerged implant. Thus, the purpose of this study is to histometrically examine crestal bone changes around machined versus SLA-surfaced implant collars in a side-by-side comparison.

Expression and function of 5-hydroxytryptamine 4 receptors in smooth muscle preparations from the duodenum, ileum, and pelvic flexure of horses without gastrointestinal tract disease

OBJECTIVE: To evaluate the expression of the 5-hydroxytryptamine 4 (5-HT4) receptor subtype and investigate the modulating function of those receptors on contractility in intestinal tissues obtained from horses without gastrointestinal tract disease. SAMPLE POPULATION: Smooth muscle preparations from the duodenum, ileum, and pelvic flexure collected immediately after slaughter of 24 horses with no history or signs of gastrointestinal tract disease. PROCEDURES: In isometric organ baths, the contractile activities of smooth muscle preparations in response to 5-hydroxytryptamine and electric field stimulation were assessed; the effect of tegaserod alone or in combination with 5-hydroxytryptamine on contractility of intestinal specimens was also investigated. Presence and distribution of 5-HT4 receptors in intestinal tissues and localization on interstitial cells of Cajal were examined by use of an immunofluorescence technique. RESULTS: Widespread 5-HT4 receptor immunoreactivity was observed in all intestinal smooth muscle layers; 5-HT4 receptors were absent from the myenteric plexus and interstitial cells of Cajal. In electrical field-stimulated tissue preparations of duodenum and pelvic flexure, tegaserod increased the amplitude of smooth muscle contractions in a concentration-dependent manner. Preincubation with tegaserod significantly decreased the basal tone of the 5-HT-evoked contractility in small intestine specimens, compared with the effect of 5-HT alone, thereby confirming that tegaserod was acting as a partial agonist. CONCLUSIONS AND CLINICAL RELEVANCE: In horses, 5-HT4 receptors on smooth muscle cells appear to be involved in the contractile response of the intestinal tract to 5-hydroxytryptamine. Results suggest that tegaserod may be useful for treatment of reduced gastrointestinal tract motility in horses.

Dissecting Carotenoid from Structural Components of Carotenoid-Based Coloration: A Field Experiment with Great Tits (Parus major)

Carotenoid-based yellowish to red plumage colors are widespread visual signals used in sexual and social communication. To understand their ultimate signaling functions, it is important to identify the proximate mechanism promoting variation in coloration. Carotenoid-based colors combine structural and pigmentary components, but the importance of the contribution of structural components to variation in pigment-based colors (i.e., carotenoid-based colors) has been undervalued. In a field experiment with great tits (Parus major), we combined a brood size manipulation with a simultaneous carotenoid supplementation in order to disentangle the effects of carotenoid availability and early growth condition on different components of the yellow breast feathers. By defining independent measures of feather carotenoid content (absolute carotenoid chroma) and background structure (background reflectance), we demonstrate that environmental factors experienced during the nestling period, namely, early growth conditions and carotenoid availability, contribute independently to variation in yellow plumage coloration. While early growth conditions affected the background reflectance of the plumage, the availability of carotenoids affected the absolute carotenoid chroma, the peak of maximum ultraviolet reflectance, and the overall shape, that is, chromatic information of the reflectance curves. These findings demonstrate that environment-induced variation in background structure contributes significantly to intraspecific variation in yellow carotenoid-based plumage coloration.

Adsorption of Enamel Matrix Proteins to a Bovine Derived Bone Grafting Material and its Regulation of Cell Adhesion, Proliferation and Differentiation

The use of various combinations of enamel matrix derivative (EMD) and grafting materials has been shown to promote periodontal wound healing/regeneration. However, the downstream cellular behavior of periodontal ligament (PDL) cells and osteoblasts has not yet been studied. Furthermore, it is unknown to what extent the bleeding during regenerative surgery may influence the adsorption of exogenous proteins to the surface of bone grafting materials and the subsequent cellular behavior. In the present study, the aim is to test EMD adsorption to the surface of natural bone mineral (NBM) particles in the presence of blood and determine the effect of EMD coating to NBM particles on downstream cellular pathways, such as adhesion, proliferation, and differentiation of primary human osteoblasts and PDL cells.