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PubMed2003

Time trends in the consumption of dairy foods in German children and adolescents.

OBJECTIVE: Examination of time trends in the consumption of dairy food and their impact on fat and calcium intakes in German children and adolescents. DESIGN: Dietary records from the DONALD Study (DOrtmund Nutritional and Anthropometric Longitudinally Designed Study). METHODS: A total of 5068 3-day weighed dietary records from 914 1 to 13-y-old children and adolescents collected between 1986 and 2001 were analysed using a mixed linear model, in which the means of the data and the covariance structure specific to the DONALD Study were modelled. RESULTS: During the study period, the consumption of 'milk products' in children and adolescents >/=4 y remained stable, since the reduced consumption of 'fluid milk' (between -2.8 and -7.4 g/day/study year) was compensated for by an increased consumption of 'yoghurt' (between +2.4 and +3.3 g/day/study year). The consumption of 'cheese' increased in subjects >/=4 y (between +0.2 and +0.7 g/day/study year). In 1 to 3-y-old children, the decreased intake of 'fluid milk' (-6.5 g/day/study year) was not compensated for by the increased intake of 'formula' (+3.5 g/day/study year). The percentage of 'low-fat milk products' significantly increased (although not significant in 9-13-y-old boys) to nearly 25% of milk products. The impact of dairy food on fat intake (as percentage of energy intake) remained stable with the exception of a slight reduction in 4-8 y olds, the impact of dairy on calcium (as percentage of US adequate intake) decreased only in 1-3 y olds. CONCLUSIONS: The consumption of dairy food remained widely stable over time in >/=4-y-old children and adolescents, but decreased in 1-3 y olds. A further decline in this age group would be undesirable as is the shift from common milk to formula. The intake of 'low-fat milk products' increased and should be continuously promoted.

Adolescent↗

PubMed2003

Genetic and maternal effect influences on viability of common frog tadpoles under different environmental conditions.

The influence of environmental stress on the expression of genetic and maternal effects on the viability traits has seldom been assessed in wild vertebrates. We have estimated genetic and maternal effects on the viability (viz probability of survival, probability of being deformed, and body size and shape) of common frog, Rana temporaria, tadpoles under stressful (low pH) and nonstressful (neutral pH) environmental conditions. A Bayesian analysis using generalized linear mixed models was applied to data from a factorial laboratory experiment. The expression of additive genetic variance was independent of pH treatments, and all traits were significantly heritable (survival: h2 approximately 0.08; deformities: h2 approximately 0.26; body size: h2 approximately 0.12; body shape: h2 approximately 0.14). Likewise, nonadditive genetic contributions to variation in all traits were significant, independent of pH treatments and typically of magnitude similar to the additive genetic effects. Maternal effects were large for all traits, especially for viability itself, and their expression was partly dependent on the environment. In the case of body size, the maternal effects were mediated largely through egg size. In general, the results give little evidence for the conjecture that environmental stress created by low pH would impact strongly on the genetic architecture of fitness-related traits in frogs, and hamper adaptation to stress caused by acidification. The low heritabilities and high dominance contributions conform to the pattern typical for traits subject to relatively strong directional selection.

Analysis of Variance↗

PubMed2004

Heterosis and epistasis for teat number and fluctuating asymmetry in crosses between Jiaxing and Iberian pigs.

In the framework of Wright's view of evolution, long-separate breeds of domestic animals could establish different adaptive epistatic genetic complexes that could be destroyed in crossbred animals by recombination. The objective of this study was to evaluate heterosis and recombination effects in a crossing experiment involving two distinct European and Asian breeds (Iberian and Jiaxing) in the F1 and two successive backcrosses to the Iberian line. Teat number (TN) was recorded in the right and left sides of piglets and analysed by fitting a mixed linear model including the Dickerson's crossbreeding parameters. TN in pigs is a discontinuous and often canalised trait presenting bilateral symmetry. The minor differences between sides make this trait a good candidate to evaluate fluctuating asymmetry (FA) and developmental instability. For TN, the posterior means and standard deviations (SD) of the heritability and of the relative contribution of common litter environmental effect to variance were 0.248 (0.028) and 0.057 (0.019), respectively. The respective values of the difference between breeds, heterosis and recombination effect were 9.990 (0.411), -0.506 (0.196) and 0.684 (0.232). For FA, the posterior means and SDs of the heritability and of the relative contribution of common litter environmental effect to variance were 0.023 (0.005) and 0.014 (0.005), respectively. Another significant genetic effect was a recombination effect of 0.773 (0.117). These results confirm that the rupture by recombination of coadapted genomes decreases developmental stability in domestic pigs.

Animals↗

PubMed2026

Characterizing Submental Neuromuscular Activity of Swallowing Rehabilitation: An Electromyographic Evaluation of Rehabilitative Maneuvers in Healthy Adults.

PURPOSE: The effortful swallow (ES), the Mendelsohn maneuver (MM), and isometric tongue presses (TPs) are widely used swallowing maneuvers/exercises to improve elements of swallowing, such as muscle strength and biomechanics. However, the underlying neuromuscular mechanisms of these exercises remain unclear, potentially limiting our ability to specify treatment targets and improve treatment efficacy. This study aimed to compare submental neuromuscular activation patterns during the ES, MM, TPs, and typical swallows in healthy young and older adults. METHOD: As part of a larger randomized crossover validation study, 60 healthy adults (30 young and 30 older) completed typical swallows and three maneuvers using a wearable submental surface electromyographic (sEMG) system (i-Phagia). Outcome variables included (a) normalized mean sEMG amplitude and (b) time to peak sEMG amplitude. Linear mixed models were used to examine effects of task, age, and sex on both outcomes. RESULTS: Normalized mean amplitude was significantly different across tasks. Post hoc pairwise comparisons confirmed that all three maneuvers produced higher normalized mean sEMG amplitude than typical swallows, with the ES eliciting the highest amplitude across age groups. Time to peak amplitude differed significantly across tasks, with typical swallows requiring the shortest time to reach peak amplitude, followed by the ES, MM, and TP. CONCLUSIONS: The ES required the highest neuromuscular effort with the shortest time to reach peak amplitude, suggesting its potential for targeting submental muscle power. Typical swallows required the least neuromuscular effort with the shortest time to reach peak amplitude, suggesting their potential for training submental muscle speed. The MM and TP may also improve submental muscle strength; however, given their temporal requirements (longer durations), they may be more beneficial for targeting coordination and endurance, though more research in this area is warranted. These findings underscore the importance of task-specific neuromuscular profiling to inform mechanism-based swallowing rehabilitation. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.32948549.

Humans↗

PubMed2003

Decay of acquired colostral antibodies to Actinobacillus pleuropneumoniae in pigs.

The main objective of this study was to estimate the decay of acquired colostral antibodies to Actinobacillus pleuropneumoniae serotype 2 in pigs. Data were obtained from pigs in an isolated cohort of 47 pigs born to five sows seropositive to A. pleuropneumoniae serotype 2. The pigs were examined serologically at 18 different times from birth until an age of about 22 weeks, using an A. pleuropneumoniae serotype 2-specific blocking enzyme-linked immunosorbent assay. Antibody concentration was expressed as an OD% derived from the optical density of the sample and the median from eight wells without serum on the same plate. A non-linear mixed model assuming a constant rate of decay (half-life) was specified and fitted to the serological data. To estimate the between-pig variability of different components, between-pig random effects of each component of the model were estimated. The estimated average half-life of acquired colostral antibodies was approximately 2 weeks, but there was a considerable variation between pigs (half-life ranged from 1-3 weeks). The duration until acquired colostral antibodies were no longer detectable ranged from 2 weeks to 2 months postpartum among the pigs in the study, mainly depending on the initial level of acquired colostral antibodies to A. pleuropneumoniae serotype 2.

Actinobacillus Infections↗

PubMed2003

Variability of heart rate correction methods for the QT interval.

AIMS: To compare variability of heart rate-corrected QT intervals (QTc) using three different methods in a study of low-dose oral haloperidol. METHODS: In a randomized, double-blind, placebo-controlled, crossover trial, we studied QT interval pharmacodynamics of single doses of oral haloperidol (10 mg) in 16 healthy subjects. Heart rate correction of the QT interval was performed using Bazett's, Fridericia's and subject-specific correction methods. The subject-specific correction was performed using linear mixed modelling of placebo period QT vs RR data from each study subject. RESULTS: The subject-specific correction, in the form of QTc = QT/RRalpha, yielded a correction term alpha (slope of the log-transformed QT vs RR relationship) that ranged from 0.23 to 0.38 in individual subjects, i.e. the fixed correction term alpha = 0.5 of Bazett's correction was outside and the fixed correction term alpha = 0.33 of Fridericia's correction inside the range of individual values. The mean absolute slope of the QTcvs RR regression line using the subject-specific correction was significantly lower than the mean slopes obtained using either Bazett's or Fridericia's corrections. All three methods revealed a statistically significant greater mean QTc on haloperidol than on placebo at 10 h post-drug administration. The mean QT (95% CI) was 421.6 (410.8, 432.4), and 408.4 (398.6, 417.8) on haliperidol and placebo, respectively, using the subject-specific correction method (P = 0.0053). The mean QTc (95% CI) was 425.4 (414.3, 436.5) and 403.1 (394.3, 411.9) on haliperidol and placebo, respectively, using Bazett's correction (P = 1.7 x 10-5) and 423.1 (412.6, 433.6) and 408.2 (398.6, 417.8) on haliperidol and placebo, respectively, using Fridericia's correction (P = 7.7 x 10-4). Raw P-values were calculated using a paired t-test. Bonferroni-corrected P-values were calculated by multiplying the raw P-values by 13. CONCLUSION: Haloperidol caused a statistically significant mean QTc prolongation using the three correction methods. The QTc intervals were less dependent on RR intervals using the subject-specific method, thus decreasing the possibility of over- or under-correction. The interindividual QTc changes from baseline varied significantly depending on the method of correction used.

Administration, Oral↗

PubMed2002

Hormone-dependent fluctuations of pressure pain threshold and tactile threshold of the temporalis and masseter muscle.

In order to better objectify reported pain and disturbed sensation, psychophysical parameters as pressure pain threshold (PPT) and tactile threshold (TT) have been introduced in pain research. The present study evaluated fluctuations of these parameters, obtained using an algometer (PPT) and von Frey hairs (TT), in relation to fluctuations in female reproductive hormones. Ten students not using oral contraceptives and eight students using oral contraceptives participated in the study. In addition, seven male students served as a control group. During two menstrual cycles, the PPT and TT of the masseter and temporalis muscles, as well as from the hand, were obtained twice per week. At the end of the study the values were evaluated in relation to the different phases of the menstrual cycle, by means of a linear mixed model. The TT appeared very reproducible within subjects and did not fluctuate over time. Scores on the left temporalis muscle appeared significantly higher than that on the right side. In all subjects the PPT tended to be higher on the left side, while in students using oral contraceptives, the PPT values of the temporalis muscle were significantly higher in the menstrual phase, and lower in the follicular phase. A significant correlation between the PPT of the temporalis muscle and the TT of the overlying skin was observed.

Adult↗

PubMed2000

Illumination levels in nursing home patients: effects on sleep and activity rhythms.

Studies examining levels of illumination in adult populations have demonstrated that the level and amount of light exposure are lower in the elderly compared with younger adults, particularly in institutionalized patients with dementia. Although insufficient light exposure has been implied as a cause of sleep fragmentation, evidence for such a relationship is scant. Sixty-six institutionalized elderly had their activity and light exposure monitored for a 3-day period. Mean and median light levels, minutes spent over 1000 and over 2000 lux, percent sleep and wake, and number of naps were computed for daytime intervals, defined as 07.00-18.59. Percentages of sleep and wake, number of awakenings and mean duration of wake periods were computed for night-time intervals, defined as 22.00-05.59. Mesor, amplitude and acrophase of activity and of light were determined by cosinor analysis. A mixed linear model was used to assess the effects of daytime Actillume measures on subsequent night-time measures, and vice versa. Spearman correlations were computed, and multiple regression analyses were carried out with light variables and dementia level as predictors and sleep-wake and activity measures as dependent variables. The median light level was 54 lux and a median of only 10.5 min were spent over 1000 lux. Higher light levels predicted fewer night-time awakenings, and severe dementia predicted more daytime sleep and lower mean activity. Increased bright light exposure predicted later activity acrophase. There was an association between the acrophases of light and of activity, with maximum illumination preceding peak activity. These results suggest that daytime light exposure has an impact on both night-time sleep consolidation and timing of peak activity level.

Aged↗

PubMed2003

Day-to-day variability in glomerular filtration rate in normal dogs by scintigraphic technique.

The sources of variability in variability of scintigraphic measurements of glomerular filtration rate (GFR) have not been determined. The day to day variability of GFR was studied in 18 healthy beagle dogs. The renal uptake of 99mTc-diethylenetriaminepentaacetic acid (DTPA) of each dog was measured using a scintigraphic technique three times at intervals of 5-26 days. GFR was calculated from a regression equation relating uptake to plasma clearance, derived in our laboratory. The mean GFR was 3.97 +/- 0.72 (SD) ml/min/kg with values from 2.66 to 5.67 ml/min/kg. Analysis of variance (ANOVA) using a linear mixed model showed that most variability is a result of the dogs, less because of day to day variability and very little to the measurement variability. The repeatability coefficients for the day to day variability and measurement variability were 1.06 and 0.21 ml/min/kg respectively. The day to day variability can be caused by physiological homeostatic adjustments by the kidneys needed because of fluctuations in food and fluid intake, each dog's individual capacity to adjust, and to intrinsic errors in the measurement method. These results should be considered when using the scintigraphic method for clinical evaluation and research.

Animals↗

PubMed2002

Objective assessment of a surgical trainee.

BACKGROUND: Early assessment of surgical trainees in their training programme is essential. A strong subjective observer's bias occurs when using the mentor assessment form. In-service examinations and qualifying examinations are only valid measurements of the trainee's knowledge of factual material. An objective method to assess a surgical trainee's clinical performance is introduced in the present study. METHODS: We examined the Generalized Linear Mixed Model statistical methodology to obtain standardized performance scores that would identify good and poor performers while taking into account the effects of patients' risk factors. Data regarding the postappendectomy complication occurrence and operation duration were retrospectively collected for each trainee. These variables were analysed by applying logistic regression and proportional hazards regression models respectively. Standardized trainee scores were obtained as by-products that measured the residual effect of surgeons' performances after taking into account the effects of possible risk factors. RESULTS: A total of 37 trainees were involved in 638 appendectomy operations from 1994 to 1997. Age, concurrent medical disease and presence of pus were significant risk factors associated with complication occurrence. Concurrent medical disease, presence of pus, operative findings of gangrenous or ruptured appendix as well as the experience of the surgeon had a significant effect on the operation duration. The present study identifies four trainees that displayed good clinical performance, and one trainee that displayed poor clinical performance of appendectomy. CONCLUSION: Our proposed method makes use of recently developed statistical methodology for predicting the effect of surgeons' performance,taking into account variations in their case-mix and their patients' fitness. This approach may serve as a very powerful tool for early assessment of a trainee's clinical proficiency, and may also have implications for the future assessment of a surgeon's clinical standard.

Appendectomy↗

PubMed2001

Long-term fluctuations of pressure pain thresholds in healthy men, normally menstruating women and oral contraceptive users.

The aim of this investigation was to evaluate whether the pressure pain threshold (PPT) in masticatory muscles of symptom-free subjects was influenced by fluctuations of the sex hormones. The PPT was measured with an electronic algometer for at least 10 consecutive menstrual cycles in 10 women using oral contraceptives and 10 women not using oral contraceptives, with a regular menstrual cycle (26-31 days). In addition, 10 men were measured in a regular pattern over a period of 1 year. All subjects were symptom-free with an age range between 18 and 39 years. Measurement sessions were held during three different cycle phases (follicular, luteal, perimenstrual) and each session consisted of four consecutive PPT measurements. By means of a linear mixed model (SAS), the PPTs of the masster, temporalis and thumb muscles were compared between: (1) groups, (2) sex-hormonal phases, (3) the four consecutive measurements of each muscle per session and (4) time. The PPTs of the masseter (p = 0.8419) and temporalis muscles (p = 0.2786) did not change significantly over time. There was no significant difference in variance for the masseter (p = 0.6250), temporalis (p = 0.9705) and thumb (p = 0.7446) between the three groups. The PPTs of all muscles were significantly lower during the perimenstrual phases in the two female groups. The present data showed similar patterns of PPTs for the three muscle groups. Moreover, the results have shown a very good consistency of the PPTs over a long time period, both in males and females.

Adult↗

PubMed2005

Time profiles of peritoneal and renal clearances of different uremic solutes in incident peritoneal dialysis patients.

BACKGROUND: Residual renal function (RRF) contributes substantially to the adequacy of peritoneal dialysis (PD). In the presence of RRF, maintenance of an adequate fluid balance is facilitated, level of systemic inflammation is lower, and renal endocrine functions are preserved. The beneficial impact of RRF also may be related to the preservation of specific renal elimination mechanisms, such as tubular metabolism or secretion, which are crucial for the removal of some uremic retention solutes. METHODS: Time profiles of peritoneal and renal clearances of urea nitrogen (60 d), creatinine (113 d), phosphate (96 d), the middle molecule beta2-microglobulin (beta2M; 11.8 kd), and the protein-bound solute p-cresol (108 d) were investigated prospectively in 24 incident PD patients. Data were analyzed by using the linear mixed models procedure. RESULTS: During a median follow-up of 7.2 months (range, 5.6 to 8.6 months), RRF (P = 0.001) and 24-hour urine volume (P = 0.004) declined significantly. Twenty-four-hour peritoneal drainage volume increased (P < 0.0001). Renal clearances of urea nitrogen (P = 0.0002), creatinine (P = 0.001), and phosphate (P = 0.001) decreased. Peritoneal clearances of these solutes increased (P = 0.002, P < 0.0001, and P < 0.0001, respectively). There was a decline in renal clearances of beta2M (P = 0.0004) and p-cresol (P < 0.0001). No change in peritoneal clearances of these solutes was noted (P = 0.188 and P = 0.559, respectively). CONCLUSION: Increasing PD dose may compensate for deteriorating RRF with respect to the elimination of water-soluble solutes. This is not the case for the middle molecule beta2M and the protein-bound solute p-cresol.

Adult↗

PubMed2006

[Differences in small area prevalence of respiratory diseases in children: challenges of an investigation initiated by parents].

OBJECTIVE: The aim of our study was to assess the prevalence of respiratory diseases in children living in a rural area in Bavaria in a systematic and standardised way to clarify whether a disease cluster exists. Reports from a parents' initiative claiming an increase of diseased children and assuming an association with air pollution due to nearby industrial sources and heavy traffic were the reason for the study. METHODS: Parents of all children living in small towns specified by the parents' initiative as affected region (central area) and parents of those children aged 6-7 or 13-14 years living in adjacent areas (control area) were asked to complete a written questionnaire. In bivariate analysis, differences in prevalences between the central area and the control area were assessed by the chi (2) test. In multivariate analysis, confounder-adjusted odds ratios with 95 % confidence intervals were calculated by logistic regression. In addition, generalized linear mixed models were used to control for potential clusters in families. RESULTS: The response rate was rather low (total 46 %, central area 53 %, control area 34 %). The study population comprised 121 girls and 141 boys. There was a pattern of increased prevalences of cough, wheeze and respiratory diseases caused by infections in children living in the central area compared to the control area. However, statistical significance was rarely observed. No systematic differences were observed for the prevalence of allergic rhinitis and atopic dermatitis. Selection bias due to varying response rates in the central versus the control area and information bias introduced by the preceding intensive public discussion could not be excluded. The comparison of prevalences detected in the small area with published data from other epidemiological studies in Germany did not indicate a systematically increased prevalence of respiratory symptoms or physician-diagnosed respiratory diseases in children from the whole area as well as in children from the central area only. CONCLUSION: This study exemplifies the challenges of small area investigations initiated by the residential community to clarify an assumed disease cluster caused by environmental pollution. The prior comparison of small area prevalence data with results of other epidemiological studies aids the decision making as to whether a detailed study with comprehensive assessment of individual exposure is justifiable.

Adolescent↗

PubMed2003

Leisure activities and the risk of dementia in the elderly.

BACKGROUND: Participation in leisure activities has been associated with a lower risk of dementia. It is unclear whether increased participation in leisure activities lowers the risk of dementia or participation in leisure activities declines during the preclinical phase of dementia. METHODS: We examined the relation between leisure activities and the risk of dementia in a prospective cohort of 469 subjects older than 75 years of age who resided in the community and did not have dementia at base line. We examined the frequency of participation in leisure activities at enrollment and derived cognitive-activity and physical-activity scales in which the units of measure were activity-days per week. Cox proportional-hazards analysis was used to evaluate the risk of dementia according to the base-line level of participation in leisure activities, with adjustment for age, sex, educational level, presence or absence of chronic medical illnesses, and base-line cognitive status. RESULTS: Over a median follow-up period of 5.1 years, dementia developed in 124 subjects (Alzheimer's disease in 61 subjects, vascular dementia in 30, mixed dementia in 25, and other types of dementia in 8). Among leisure activities, reading, playing board games, playing musical instruments, and dancing were associated with a reduced risk of dementia. A one-point increment in the cognitive-activity score was significantly associated with a reduced risk of dementia (hazard ratio, 0.93 [95 percent confidence interval, 0.90 to 0.97]), but a one-point increment in the physical-activity score was not (hazard ratio, 1.00). The association with the cognitive-activity score persisted after the exclusion of the subjects with possible preclinical dementia at base line. Results were similar for Alzheimer's disease and vascular dementia. In linear mixed models, increased participation in cognitive activities at base line was associated with reduced rates of decline in memory. CONCLUSIONS: Participation in leisure activities is associated with a reduced risk of dementia, even after adjustment for base-line cognitive status and after the exclusion of subjects with possible preclinical dementia. Controlled trials are needed to assess the protective effect of cognitive leisure activities on the risk of dementia.

Aged↗

PubMed2002

Variability in cost of coronary bypass surgery in New York State: potential for cost savings.

OBJECTIVE: Previous analyses of variability in bypass resource use have not focused on hospital-level variation or adequately explored the influence of patient risk. We combined a clinical database with claims data to fully characterize patient level and hospital level variability in bypass surgery cost and length of stay in New York State and explored the extent to which lower cost is associated with worse quality of care. METHODS: By use of 1992 clinical and claims data, we identified by multivariable regression which patient characteristics influence bypass cost and length of stay. Hospital was then incorporated as a random variable in mixed linear models to determine its impact on resource use. The relationship between risk-adjusted in-hospital mortality and cost was then explored. RESULTS: In the 21 hospitals for which cost data were available, mean leveled cost (exclusive of professional fees and noncomparable costs) was $15,713, with a mean length of stay of 14 days (n = 12,087). One fifth of the variation in resource use was explained by baseline patient risk. After adjustment for patient risk, hospital explained an additional 42% of variation in cost and an additional 8% of variation in length of stay. Among hospitals, risk-adjusted cost varied almost 3-fold and risk-adjusted length of stay varied 50%. There was no association between cost and in-hospital mortality. CONCLUSIONS: As of 1992, there was considerable interhospital variability in bypass surgery cost after patient baseline risk was accounted for. This suggests that reductions in bypass cost could be achieved by normalizing clinical practice.

Aged↗

PubMed2001

Dilation of the sinotubular junction causes aortic insufficiency after aortic valve replacement with the Toronto SPV bioprosthesis.

OBJECTIVE: This study was undertaken to examine the causes of late aortic insufficiency in patients who had aortic valve replacement with the Toronto SPV bioprosthesis (St Jude Medical, Inc, St Paul, Minn). METHODS: From 1991 to 1996, 174 patients with a mean age of 63 +/- 11 years underwent aortic valve replacement with the Toronto SPV bioprosthesis and were evaluated annually by Doppler echocardiographic studies to assess valve function. The diameters of the aortic root were retrospectively measured in all patients who had aortic insufficiency and also in a random sample of 23 patients without aortic insufficiency. The mean follow-up was 5.8 years (range 4 to 9 years). RESULTS: Aortic insufficiency greater than 1+ developed in 19 patients. The diameter of the sinotubular junction increased in these patients and did not change in those without aortic insufficiency. The ratio between the diameter of the sinotubular junction and the size of the Toronto SPV bioprosthesis increased in patients who had aortic insufficiency and did not change in those without aortic insufficiency. Both 2-way analysis of covariance and analysis by a mixed linear model demonstrated a significant difference in slopes between the patients with aortic insufficiency greater than 1+ and in those without insufficiency for the ratio of the diameter of the sinotubular junction/diameter of the Toronto SPV relationships over time (aortic insufficiency. Year; P <.001). Structural valve deterioration was observed in 5 valves, and in 4 of them the sinotubular junction of the aortic root had dilated. The freedom from structural valve deterioration was 99% +/- 1% for patients without aortic insufficiency and 82% +/- 12% for those with aortic insufficiency of more than 1+ at 8 years (P =.004). One patient had moderate aortic insufficiency without structural valve deterioration and dilation of the sinotubular junction. CONCLUSIONS: Dilation of the sinotubular junction causes aortic insufficiency after aortic valve replacement with the Toronto SPV bioprosthesis and increases the risk of structural valve deterioration. Banding the sinotubular junction may prevent dilation and enhance the durability of this valve.

Aortic Valve↗

PubMed2005

Evaluating the effectiveness of a participatory ergonomics approach in reducing the risk and severity of injuries from manual handling.

Manual handling is the greatest contributor to non-fatal injury and disease in the workplace, commonly accounting for one-third of national injury counts. Interventional strategies that have focused on selecting or modifying the worker have been ineffective in reducing injury risk. In recent times, participatory ergonomics has been widely adopted as a process to reduce the risk of injury from manual handling but it is not well validated as an intervention. This study evaluated the effectiveness of a participatory ergonomics risk assessment approach in reducing the rate and severity of injuries from manual and non-manual handling sustained by a cohort of 137 cleaners within a hospital setting. The date of injury and the workers' compensation claim cost and hours lost from work were obtained for each injury incurred during the 4-year pre-intervention and 3-year intervention period. The age, gender and hours worked were ascertained for every cleaner whether injured or not. Using generalized linear mixed modelling analysis, reductions of rate of injury by two-thirds, workers' compensation claim costs by 62% and hours lost by 35% for manual handling injuries were found to be associated with the intervention period. Although the cleaners experienced a significant intervention period reduction in non-manual handling injury rate, the corresponding changes in severity of injury were not significant. The success of the intervention supports the adoption of a participatory ergonomics approach in reducing the rate and consequence of injuries in the workplace.

Adult↗

PubMed2025

Mindfulness and Sex Education for Sexual Dysfunction in Breast Cancer Survivors: Mediators and Moderators of Treatment Outcome.

Mindfulness-based cognitive therapy (MBCT) and supportive-expressive sex education therapy (STEP) are effective group treatments for sexual dysfunction after breast cancer (BrCa). We explored mediators and moderators of outcomes following the 8-week groups. BrCa survivors (n = 116, mean age = 49.9 ± 9.5) were randomized to group and completed measures before, immediately after, and 6 months after treatment. Mediators assessed were changes in depression, chronic pain acceptance, pain catastrophizing, and trait mindfulness. Potential moderators included age, treatment expectations, baseline mental health, cancer treatment duration, use of chemotherapy, and adjuvant endocrine therapy. Longitudinal mediation and moderation were assessed using linear mixed models. Increases in pain acceptance mediated improvements in sexual desire and reductions in both sexual distress and vaginal pain. Decreases in pain catastrophizing mediated improvements in sexual distress. Higher expectations for treatment led to greater reductions in sexual distress. Those with low baseline anxiety showed greater improvements in desire and distress. Low baseline depression predicted greater improvements in desire, but only in the STEP arm. Older STEP participants improved significantly more than younger STEP participants. Cancer-related treatment variables, and the impact of adjuvant endocrine therapy, had differential effects on outcomes based on the treatment arm of the study. In conclusion, treatments aimed at improving pain acceptance and pain catastrophizing are likely to promote improvements in sexual health among BrCa survivors, and factoring in patients' expectations about treatment improvements, depression and anxiety, age, duration of cancer treatment, chemotherapy, and adjuvant hormonal therapy may help to guide treatment recommendations for sexual dysfunction.

Humans↗