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Purpose: To complete a scoping review of meta-analyses summarizing evidence of the effectiveness of Tai Chi for adults with health conditions., Materials and Methods: Meta-analyses were retrieved from Medline, Embase, AMED, CINAHL, SPORTDiscus, PsychINFO, Web of Science, PubMed Health and the Cochrane Library from database inception to early September 2018. Multistage deduplication and screening processes identified full-length, unique, peer-reviewed meta-analyses. Two people independently appraised 42 meta-analyses based on the GRADE system and organized results into 3 appendices subsequently collated into heterogeneous, statistically significant, and statistically insignificant tables., Results: "High" and "moderate" quality evidence indicates that Tai Chi can significantly benefit adults with health conditions including cancers, chronic obstructive pulmonary disease, coronary heart disease, depression, heart failure, hypertension, low back pain, osteoarthritis, osteoporosis, Parkinson's Disease and stroke. Outcomes included significant improvements in activities of daily living, balance, exercise capacity, gait, mastery, mental health, mobility, motor function, participation in daily life, physical function, quality of life, range of motion, and strength; with reductions in blood pressure, body mass index, depression, disability, dyspnea, falls, fatigue, pain, stiffness, and waist circumference., Conclusions: Healthcare providers now have information to advise clients with health conditions on the effectiveness of Tai Chi for overall health promotion. IMPLICATIONS FOR REHABILITATIONTai Chi is a form of safe, enjoyable, light-to-moderate aerobic physical activity for adults that is inexpensive to implement in diverse community settings.Adults with health conditions require physical activity for prevention of secondary impairments and over-all health promotion.This scoping review of meta-analyses elucidates "high" and "moderate" quality evidence of the effectiveness of Tai Chi in improving important outcomes for people with numerous health conditions.This information can be useful for healthcare providers who wish to recommend effective community-based physical activity to clients they are serving.

Our current understanding of the etiology and maintenance of eating disorders and obesity continues to be far from complete. Similarly, our understanding of determinants of both successful and unsuccessful weight loss surgery is also quite limited. While a number of research methodologies have been applied to these areas, one methodology that has recently seen a rise in popularity is the use of ecological momentary assessment (EMA). EMA allows one to study a variety of variables of interest in the natural environment. The study of eating disorders, obesity, and bariatric surgery has all been conducted using EMA recently. The current study is a review of these areas and summarizes the recent literature (past 3 years) in eating disorders, obesity, and bariatric surgery using EMA methodology.

Purpose of Review: Individuals who undergo bariatric surgery typically experience outcomes of marked weight loss and improvements in medical comorbidities and psychological functioning. Unfortunately, a significant minority of patients also experience problems, such as reoccurring or new psychiatric disorders, alcohol or substance abuse, or eating disorders. In the current manuscript, we explore empirical studies published in the past year that are relevant to this topic., Recent Findings: In the area of psychiatric disorders, we focus on depression and anxiety, with several studies showing initial improvement in depression and anxiety symptoms followed by deterioration in the following years. Research in alcohol use has revealed a trend in which alcohol consumption decreases or ceases immediately following surgery, but often increases over time. Some studies have recently compared alcohol use across different types of surgery, which may help clarify a potential biological component of these problems. Finally, some eating disordered behaviors, which have until now received relatively little attention, have been further studied, with subthreshold loss-of-control eating behaviors receiving increased empirical examination., Summary: Stemming from these findings, we suggest several directions to take for future research. With respect to psychiatric disorders, a closer examination of the effect of weight regain on related psychiatric comorbidities would prove valuable in determining the risk of disorder development. The mechanism by which the rate of alcohol consumption is altered following surgery has been proven elusive, and focusing further scrutiny on the differences in consumption between surgical procedures could prove useful in deciphering it. And with regards to eating disorders, a closer examination of both full diagnostic and less common eating disorders following bariatric surgery would be prudent.

Background: We evaluated the accuracy and repeatability of a 3D method for polyethylene acetabular cup wear measurements using computed tomography (CT). We propose that the method be used for clinical in vivo assessment of wear in acetabular cups., Material and Methods: Ultra-high molecular weight polyethylene cups with a titanium mesh molded on the outside were subjected to wear using a hip simulator. Before and after wear, they were (1) imaged with a CT scanner using a phantom model device, (2) measured using a coordinate measurement machine (CMM), and (3) weighed. CMM was used as the reference method for measurement of femoral head penetration into the cup and for comparison with CT, and gravimetric measurements were used as a reference for both CT and CMM. Femoral head penetration and wear vector angle were studied. The head diameters were also measured with both CMM and CT. The repeatability of the method proposed was evaluated with two repeated measurements using different positions of the phantom in the CT scanner., Results: The accuracy of the 3D CT method for evaluation of linear wear was 0.51 mm and the repeatability was 0.39 mm. Repeatability for wear vector angle was 17°., Interpretation: This study of metal-meshed hip-simulated acetabular cups shows that CT has the capacity for reliable measurement of linear wear of acetabular cups at a clinically relevant level of accuracy.

Our purpose was to compare the wear performance of mechanically enhanced 5Mrad highly crosslinked polyethylene (MEP, ArComXL) hip liners to (control) 3Mrad UHMWPE liners (ArCom) in 36 mm head size. As a more severe synergy of clinically relevant test models, we contrasted wear with custom roughened Co-Cr surfaces (Ra 500 nm) to the standard pristine Co-Cr heads (Ra < 20 nm) using a severe microseparation test mode in our hip simulator. We adopted a previously published model to estimate potential biological activity. On new Co-Cr heads, the MEP liners showed a 47% reduction in volumetric wear a 13% reduction in wear particle size and a 27% reduction in Functional Biological Activity (FBA) compared to our control. On rough Co-Cr heads, the MEP liners showed little advantage in terms of volumetric wear compared with the control. However, the MEP liners overall showed a 38% reduction in FBA compared to the control owing to a larger volume fraction of larger particles. Thus overall the MEP liners appeared to offer advantages in terms of reduced FBA indices., (2008 Wiley Periodicals, Inc.)

The clinical history of yttria-stabilized, zirconia (Zr) ceramic has been controversial. In the patient, combinations of hydrothermal and mechanical shocks may trigger detrimental changes in Zr balls that have inferior metastability. Transformations from tetragonal to monoclinic phase may be influenced by impingement, dislocation, and disassociation in certain patients. Hydrothermal stability was measured in Zr balls from four vendors by autoclave and mechanical models that included "cup-impingement," "abrasive" wear, and "3rd-body" wear. Standard simulator tests for polyethylene (PE) wear studies combined pristine and previously transformed Zr and were also used to test lubricant effects (Zr/Zr-serum, Zr/Zr-water, Zr/PE-water). For in-vivo comparisons we studied retrieved Zr balls at 1-15 years follow-up by laser interferometry, SEM, EDS, XRD, and Raman spectroscopy. We found that severe mechanical shock triggered local surface destruction but little transformation. In contrast, hydrothermal processes revealed 5-13% monoclinic by 7 h, increasing at a rate of 0.56%/h for 22-mm balls and 0.81%/h for 26-mm balls. The all-ceramic Zr/Zr bearings were very sensitive to lubrication mode, showing early catastrophic failure when run in water but surviving 20 million cycles when run with serum lubrication. Wear with Zr/PE combination did not trigger phase changes in water or serum but decreased the monoclinic content measured on previously transformed surfaces. Most retrieved Zr balls showed high transformation (30-85% monoclinic) but some showed no transformation. The ball areas with major monoclinic changes corresponded to PE contact, suggesting that tribological conditions under the cup were the trigger. This indicated that we understand little of the hydrothermal conditions operating under Zr/PE hip joints in-vivo., (Copyright 2007 Wiley Periodicals, Inc.)

Ion-pair interactions between pyridinium cations and various carboxylate anions are explored using noisy light based coherent anti-Stokes Raman scattering (I(2)CARS). Binary mixtures of pyridine and various carboxylic acids (including halo-acetic acids, straight-chain carboxylic acids, and pivalic acid) are prepared. A Brønsted type acid-base reaction occurs in these mixtures to create pyridinium and carboxylate ions. Both pyridine, itself, and pyridinium have strong I(2)CARS signals originating from their ring breathing modes. The vibrational frequency of the ring breathing mode for pyridine is blue-shifted by hydrogen bonding, and that same mode for pyridinium is red-shifted by ion-pair interaction. Frequency shift data for the ring breathing mode of pyridine and pyridinium are presented. These data are discussed in terms of a simplistic model for the electronic behavior of these compounds.

The effects of hydrogen bonding on the ring stretching modes (both ring breathing and triangle) of pyridine are experimentally investigated using noisy light based coherent Raman scattering spectroscopy. Three systems, pyridine/formamide, pyridine/water, and pyridine/acetic acid, provide varying degrees of strength for the diluent-pyridine hydrogen bond complex. Formamide forms a relatively weaker hydrogen bond, while acetic acid essentially fully transfers a proton to pyridine. Both dilution studies and temperature studies are performed on the three systems. Together, these provide a broad context in which a very simple model for the electronic behavior of pyridine is formulated. This model is based on a molecular orbital picture and electrostatic arguments, and it well explains the observed experimental results. Additionally, a new mechanism for the line broadening of the ring breathing mode for the pyridine-water hydrogen bonded complex is proposed.

To investigate the effects of mechanical deformation on matrix degradation in fibrous joints, coronal suture explants from neonatal rabbits were stressed in vitro for 24 hours in an established tooth-movement model system. The metalloproteinase collagenase (CL) and its inhibitor, TIMP (tissue inhibitor of metalloproteinases), were immunolocalized in two ways by a two-step indirect technique: (1) extracellularly by immunoprecipitation at the site of secretion, and (2) intracellularly by incubation of the explants with the ionophore monensin. Immunoprecipitates of CL and TIMP were distributed throughout the sutural and periosteal tissues of nonstressed explants. In stressed explants, however, CL immunoprecipitates were predominantly associated with an area of rounded cells between the bone ends. In explants treated with monensin a significant increase in the number of CL-positive cells was observed in this cellular area; active enzyme was suggested by the demonstration of CL bound to collagen. Extracellular TIMP was not seen within the area of rounded cells of stressed explants, but intracellular TIMP was detectable; this suggests that insufficient TIMP was available to immunoprecipitate with anti-TIMP, probably because it had become irreversibly complexed with active CL. Since the area of rounded cells corresponds to the site of increased cell proliferation in this and other animal models of tooth movement, these data suggest that collagenase production and cell proliferation might be correlated. We speculate that matrix degradation is an essential prerequisite for cell proliferation as it creates room to accommodate an increase in cell population.

We have isolated a cDNA clone corresponding to the Mr 38,000 catalytic subunit of bovine type 2A protein phosphatase. The cDNA was isolated from a bovine adrenal gland cDNA library through the use of oligonucleotide probes whose sequences were based on partial amino acid sequence obtained from cyanogen bromide fragments of the purified cardiac enzyme. The entire 1724-base-pair cDNA has been sequenced and found to contain an open reading frame coding for a protein of 325 amino acids having a calculated molecular weight of 37,320. The deduced amino acid sequence contains the experimentally determined sequences of five different cyanogen bromide peptides. Transfection of COS-m6 cells with the cloned cDNA resulted in transient expression of a protein that could be detected by immunoblot analysis with a monoclonal antibody directed against the purified cardiac protein phosphatase. The expressed protein had the same apparent molecular weight as the purified enzyme when analyzed by NaDodSO4/polyacrylamide gel electrophoresis, suggesting that this clone contains the entire coding region of the phosphatase mRNA. The cloned cDNA hybridizes to a mRNA of 2.0 kilobases in bovine heart and adrenal gland. Under conditions of reduced stringency, the cDNA also hybridizes to a mRNA species of 1.2 kilobases in cardiac tissue.

Two forms of protein phosphatase which dephosphorylate cardiac myosin or myosin light chains and the inhibitory subunit of cardiac troponin were purified from bovine cardiac muscle. The enzymes were composed of subunits of Mr = 63,000, 55,000, and 38,000 in a 1:1:1 molar ratio (PT-1) or Mr = 63,000 and 38,000 in a 1:1 molar ratio (PT-2). Native gel electrophoresis and sucrose gradient sedimentation indicated that activity toward all three substrates was due to a single enzyme species. A monoclonal antibody and polyclonal antiserum directed against an Mr = 38,000 protein phosphatase from this tissue specifically reacted with the Mr = 38,000 subunit of PT-1 and PT-2. The specificity of antibodies for the Mr = 38,000 subunit indicated that it was distinct from the other subunits. The Mr = 63,000 subunits of PT-1 and PT-2 were identical based on mobility on sodium dodecyl sulfate gels and one-dimensional peptide maps. Specificity of antiserum against the Mr = 55,000 subunit of PT-1 showed that this subunit was a distinct protein and not derived from the Mr = 63,000 subunit by proteolysis. PT-2 but not PT-1 could interact with antiserum against the Mr = 38,000 catalytic subunit in competitive immunoassays indicating that the presence of the Mr = 55,000 subunit may alter or mask antigenic site(s). Analysis of the enzymatic properties of PT-1 and PT-2 showed that PT-2 had higher activity with myosin, myosin light chains, and phosphorylase while PT-1 had higher activity with troponin. The results indicate that the presence of the Mr = 55,000 subunit may alter the enzymatic properties of the catalytic subunit.

The native structures of protein phosphatases have not been clearly established. Several tissues contain high molecular weight enzymes which are converted to active species of Mr approximately 35,000 by denaturing treatments or partial proteolysis. We have used a monoclonal antibody directed against purified bovine cardiac Mr = 38,000 protein phosphatase to determine whether this species is the native catalytic subunit or a proteolytic product of a larger polypeptide. Monoclonal antibody was obtained from a cloned hybrid cell line produced by the fusion of Sp2 myeloma cells with spleen cells from a mouse immunized with phosphatase coupled to hemocyanin. This antibody was specific for the Mr = 38,000 phosphatase as determined by immunoblot analysis of purified enzyme or cardiac tissue extracts after native or sodium dodecyl sulfate-polyacrylamide gel electrophoresis. A single immunoreactive protein of Mr = 38,000 was present in cardiac tissue extracts including extracts prepared from freeze-clamped rat heart rapidly denatured in hot sodium dodecyl sulfate buffer. Precipitation of cardiac extract with 80% ethanol did not alter the Mr of the phosphatase nor did it liberate new immunoreactive material not observed in the extract. Ethanol precipitation caused the dissociation of both phosphatase activity and immunoreactivity from a high Mr form to a form of Mr between 30,000 and 40,000. An immunoreactive protein of Mr = 38,000 was identified in several bovine and rat tissues as well as tissues from rabbits, mice and chickens and human HT-29 cells. From these data we conclude that the Mr = 38,000 cardiac phosphatase is a native catalytic subunit of higher molecular complexes which are dissociated by ethanol precipitation. A very similar, or identical, protein is present in several tissues and species suggesting that this catalytic subunit is a ubiquitous enzyme important in many dephosphorylation reactions.