Mechanical and electrochemical characterisation of new Ti-Mo-Nb-Zr alloys for biomedical applications.

The development and characterisation of new metallic biomaterials that contain non-toxic and non-allergic elements but possess low elastic modulus and low biodegradation rates, has become a topic of serious investigation in orthopaedic implant application. The lowering of elastic modulus and improving of corrosion resistance can be achieved by specific chemical alloying and super-elasticity effects, associated with a stress-induced phase transformation from the BCC metastable beta phase to the orthorhombic α″ martensite. Using this framework, this paper focuses on the effect of Nb and/or Zr micro-additions on the elastic modulus/yield strength balance and discusses microstructure, and the mechanical and electrochemical behaviour of four new ß-Ti-8Mo-xNb-xZr (x=2-5) alloys, using tensile tests, X-ray diffraction, SEM characterisation, ultrasound technique and potentiodynamic polarisation methods. The results reveal that the alloys exhibit a pronounced microstructural sensitivity response, with alloying elements and excellent agreement between ß-stability and high mechanical strength, with increasing Nb additions. Although all the alloys possess excellent corrosion resistance and low Young׳s modulus, Ti-8Mo-4Nb-2Zr alloy, which consists of ß+α'' phases, exhibits a low Young modulus of 35GPa, which is lower than those of the commercial alloys already used in biomedical implantation. The significant corrosion resistance, nontoxicity and better mechanical compatibility are properties pertinent to preventing stress shielding and bone resorption in orthopaedic implant applications.

A literature review of case formulation to inform mental health practice.

Changes in mental health provision have led to practitioners and service providers reviewing how they incorporate service users in assessment processes and treatment decisions. Case formulation (CF) is a framework that informs a choice of psychological treatments providing a bridge between assessment and treatment phases to guide treatment options. However, CF is not routinely practised in mental health; hence this paper reviews CF literature to establish its efficacy for service users experiencing mental health issues. The purpose of this study is to assess the efficacy, reliability and validity of CF and its process and function in providing treatment for service users experiencing mental health issues and to explore practitioner training requirements. A systematic search of English language publications on CF and treatment frameworks from 1999-2011 was conducted searching electronic databases. Additionally, two seminal pieces of CF work were included. The findings demonstrate evidence of CF's efficacy and suggest practitioner training programmes to increase professional expertise and enhance service user outcomes. However, limited evidence exists and further research is required to address efficacy and training implications of CF.

Maharishi Vedic vibration technology on chronic disorders and associated quality of life.

There is a growing interest for more effective, innovative programs to address the chronic illness suffered by approximately 40 percent of the U.S. population. The purpose of this study was to evaluate the effects of a new Maharishi Vedic Medicine program-the Maharishi Vedic Vibration Technology-on the quality of life of individuals with chronic disorders. A total of 213 individuals took part in the study (mean age=48.55 years; average length of time of chronic illness=18.42 years). Results showed that over three sessions, the average self-reported improvement in chronic illness was 40.97 percent. Conditions related to neck pain improved the most (51.25%), followed by respiratory ailments (48.00%), digestive problems (46.90%), mental health, including anxiety and depression (46.34%), arthritis (41.57%), insomnia (37.38%), back pain (36.32%), headaches (35.83%), cardiovascular conditions (22.31%), and eye problems (21.19%). Findings also showed significant reductions in frequency of discomfort or pain (p<.000001), intensity of discomfort (p<.000001), and disabling effects of the discomfort in daily activity (p<.000001), in addition to overall improvement in mental health (p<.000001) and vitality (p<.000125). Possible mechanisms of action are presented.

Behavioral treatment of hypertensive heart disease in African Americans: rationale and design of a randomized controlled trial.

African Americans experience higher morbidity and mortality than Whites do as a result of hypertension and associated cardiovascular disease. Chronic psychosocial stress has been considered an important contributing factor to these high rates. The authors describe the rationale and design for a planned randomized controlled trial comparing Transcendental Meditation, a stress-reduction technique, with lifestyle education in the treatment of hypertension and hypertensive heart disease in urban African Americans. They pretested 170 men and women aged 20 to 70 years over a 3-session baseline period, with posttests at 6 months. Outcomes included clinic and ambulatory blood pressure, quality of life, left ventricular mass measured by M-mode echocardiography, left ventricular diastolic function measured by Doppler, and carotid atherosclerosis measured by beta-mode ultrasound. This trial was designed to evaluate the hypothesis that a selected stress reduction technique is effective in reducing hypertension and hypertensive heart disease in African Americans.

Effects of stress reduction on carotid atherosclerosis in hypertensive African Americans.

BACKGROUND AND PURPOSE: African Americans suffer disproportionately higher cardiovascular disease mortality rates than do whites. Psychosocial stress influences the development and progression of atherosclerosis. Carotid intima-media thickness (IMT) is a valid surrogate measure for coronary atherosclerosis, is a predictor of coronary outcomes and stroke, and is associated with psychosocial stress factors. Stress reduction with the Transcendental Meditation (TM) program decreases coronary heart disease risk factors and cardiovascular mortality in African Americans. B-mode ultrasound is useful for the noninvasive evaluation of carotid atherosclerosis. METHODS: This randomized controlled clinical trial evaluated the effects of the TM program on carotid IMT in hypertensive African American men and women, aged >20 years, over a 6- to 9-month period. From the initially enrolled 138 volunteers, 60 subjects completed pretest and posttest carotid IMT data. The assigned interventions were either the TM program or a health education group. By use of B-mode ultrasound, mean maximum IMT from 6 carotid segments was used to determine pretest and posttest IMT values. Regression analysis and ANCOVA were performed. RESULTS: Age and pretest IMT were found to be predictors of posttest IMT values and were used as covariates. The TM group showed a significant decrease of -0.098 mm (95% CI -0. 198 to 0.003 mm) compared with an increase of 0.054 mm (95% CI -0.05 to 0.158 mm) in the control group (P=0.038, 2-tailed). CONCLUSIONS: Stress reduction with the TM program is associated with reduced carotid atherosclerosis compared with health education in hypertensive African Americans. Further research with this stress-reduction technique is warranted to confirm these preliminary findings.

Electrophysiological correlates of higher states of consciousness during sleep in long-term practitioners of the Transcendental Meditation program.

Standard ambulatory night sleep electroencephalograph (EEG) of 11 long-term practitioners of the Transcendental Meditation (TM) program reporting "higher states of consciousness" during sleep (the experimental group) was compared to that of nine short-term practitioners and 11 non-practitioners. EEG tracings during stages 3 and 4 sleep showed the experimental group to have: 1) theta-alpha activity simultaneously with delta activity and 2) decreased chin electromyograph (EMG) during deep sleep (p = 0.002) compared to short-term practitioners. Spectral analysis fast Fourier transform (FFT) data of the first three cycles showed that: 3) the experimental subjects had significantly greater theta 2 (6-8 Hz)-alpha 1 (8-10 Hz) relative power during stages 3 and 4 than the combined control groups [t(30) = 5.5, p = 0.0000008] with no difference in time in delta; 4) there was a graded difference across groups during stages 3 and 4 in theta 2-alpha 1 power, with experimentals having greater power than short-term practitioners, who in turn had greater power than non-practitioners [t(30) = 5.08, p = 0.00002]; and 5) experimentals also had increased rapid eye movement (REM) density during REM periods compared to short-term practitioners (p = 0.04). Previous studies have found increased theta-alpha EEG activity during reported periods of "transcendental consciousness" during the TM technique. In the Vedic tradition, as described by Maharishi Mahesh Yogi, transcendental consciousness is the first of a sequence of higher states. The maintenance of transcendental consciousness along with deep sleep is said to be a distinctive criterion of further, stabilized higher states of consciousness. The findings of this study are interpreted as physiological support for this model.

A controlled study of the effects of the Transcendental Meditation program on cardiovascular reactivity and ambulatory blood pressure.

Cardiovascular responses to stress reactivity has been proposed as a risk factor for hypertension. In this study, we evaluated the effects of stress reduction on both laboratory cardiovascular reactivity and ambulatory blood pressure in real life on 39 normotensive male subjects who were pretested for ambulatory blood pressure and cardiovascular reactivity to stress using a battery of laboratory stressors. Thereafter, subjects were randomly assigned to practice either the Transcendental Meditation (TM) technique or a cognitive-based stress education control (SEC) for four months. After 4 months, there was no change in cardiovascular response to stressors between the TM and control groups. However, the subjects regularly practicing TM demonstrated a significant reduction of 9 mm Hg (p < .04) in average ambulatory DBP compared to controls. Since ambulatory BP monitoring has been shown to be a better predictor of cardiovascular complications of hypertension than clinic BP, this finding may have important implications for primary prevention of CVD in normotensive subjects.

Trial of stress reduction for hypertension in older African Americans. II. Sex and risk subgroup analysis.

Our objective was to test the short-term efficacy and feasibility of two stress-reduction approaches for the treatment of hypertension in older African Americans, focusing on subgroup analysis by sex and by high and low risk on six measures of hypertension risk: psychosocial stress, obesity, alcohol use, physical inactivity, dietary sodium-potassium ratio, and a composite measure. The study involved a follow-up subgroup analysis of a 3-month randomized, controlled, single-blind trial conducted in a primary care, inner-city health center. Subjects were 127 African American men and women, aged 55 to 85 years, with diastolic pressure of 90 to 104 mm Hg and systolic pressure less than or equal to 179 mm Hg. Of these, 16 did not complete follow-up blood pressure measurements. Mental and physical stress-reduction approaches-the Transcendental Meditation technique and progressive muscle relaxation, respectively-were compared with a life-style modification education control and with each other. Both systolic and diastolic pressures changed from baseline to follow-up for both sexes and for high and low risk level (defined by median split) on the six measures of hypertension risk. Compared with education control subjects, women practicing the Transcendental Meditation technique showed adjusted declines in systolic (10.4 mm Hg, P < .01) and diastolic (5.9 mm Hg, P < .01) pressures. Men in this treatment group also declined in both systolic (12.7 mm Hg, P < .01) and diastolic (8.1 mm Hg, P < .001) pressures compared with control subjects. Women practicing muscle relaxation did not show a significant decrease compared with control subjects, and men declined significantly in diastolic pressure only (6.2 mm Hg, P < .01). For the measure of psychosocial stress, both the high and low risk subgroups using the Transcendental Meditation technique declined in systolic (high risk, P = .0003; low, P = .06) and diastolic (high risk, P = .001; low, P = .008) pressures compared with control subjects, whereas for muscle relaxation, blood pressure dropped significantly only in the high risk subgroup and only for systolic pressure (P = .03) compared with control subjects. For each of the other five risk measures, Transcendental Meditation subjects in both the high and low risk groups declined significantly in systolic and diastolic pressures compared with control subjects. Effects of stress reduction on blood pressure were found to generalize to both sexes and diverse risk factor subgroups and were significantly greater in the Transcendental Meditation treatment group. These effects (along with high compliance) even in individuals with multiple risk factors for hypertension clearly warrant longer-term investigation in this and other populations.

A randomised controlled trial of stress reduction for hypertension in older African Americans.

We tested the short-term efficacy and feasibility of two stress education approaches toe the treatment of mild hypertension in older African Americans. This was a randomized, controlled, single-blind trial with 3 months of follow-up in primary care, inner-city health center. Of 213 African American men and women screened, 127 individuals (aged 55 to 85 years with initial diastolic pressure of 90 to 109 mm Hg, systolic pressure of < or = 189 mm Hg, and final baseline blood pressure of < or = 179/104 mm Hg) were selected. Of these, 16 did not complete follow-up blood pressure measurements. Mental and physical stress reduction approaches (Transcendental Meditation and progressive muscle relaxation) were compared with a lifestyle modification education control program and with each other. The primary outcome measures were changes in clinic diastolic and systolic pressures from baseline to final follow-up, measured by blinded observers. The secondary measures were linear blood pressure trends, changes in home blood pressure, and intervention compliance. Adjusted for significant baseline differences and compared with control, Transcendental Meditation reduced systolic pressure by 10.7 mm Hg (P < .0003) and diastolic pressure by 6.4 mm Hg (P <.00005). Progressive muscle relaxation lowered systolic pressure by 4.7 mm Hg (P = 0054) and diastolic pressure by 3.3 mm Hg (P <.02). The reductions in the Transcendental Meditation group were significantly greater than in the progressive muscle relaxation group for both systolic blood pressure (P = .02) and diastolic blood pressure (P = .03). Linear trend analysis confirmed these patterns.(ABSTRACT TRUNCATED AT 250 WORDS)

Examination of alumina ceramic components from total hip arthroplasties.

Materials analysis has been conducted on retrieved Mittelmeier-Autophor ceramic components from total hip arthroplasties, correlating articulating surface wear morphology with clinical reasons for failure. Plastically deformed, agglomerated wear debris (30-60 microns) has been identified on femoral head articulation wear surfaces, displaying exaggerated wear, especially during the initiation stage. Such surfaces were associated with clinical failures involving displacement of the acetabular cup and perforation of the cortex by the femoral stem. It is thought that this wear debris may play an important role in the promotion of the 'avalanche' wear mechanism, as it is adherent and thus difficult to remove from the wear interface.