Implementation of a Community Walking Program (Walk On!) for Functionally-Limited Older Adults.

BACKGROUND: Walking interventions improve physical function, reduce fall risk, and prevent mobility disability-even in those with compromised walking ability. However, most prior studies have been conducted in controlled research settings, with no dissemination of an evidence-based walking program for older adults who have mobility limitations and/or are socially isolated. OBJECTIVES: This study reports data on the feasibility and acceptability of a community-based walking program (Walk On!) for older adults who are functionally limited, and assesses changes in physical function among attendees. The program sessions focused on long-distance walking, and took place for one-hour, for two days/week, and for 12 weeks at a time. DESIGN: Pilot implementation study. SETTING: Local church in Winston-Salem, NC. PARTICIPANTS: 49 program participants; Measurements: Physical function battery and satisfaction survey data, as well as formative evaluation data from six attendees of a focus group, are reported. RESULTS: The majority of the participants were >75 years (71%), female (65%), and presented with low levels of physical function (usual gait speed=0.79±0.16; 30.6% used an assistive device). Satisfaction with the program was high (100% would recommend it to others) and focus group results were overwhelmingly positive. Mean attendance to scheduled sessions was 77%±21%, and 63% of participants attended at least 75% of scheduled sessions (n=8 attended 100%). On average, participants improved their 6-min walk distance by 8.9%, their SPPB score by 15.4%, their timed-up-go time by 9.0%, and their usual gait speed by 11.4%. CONCLUSION: The results of the initial evaluation of Walk On! show high feasibility and acceptability of the program, as well as efficacy for improving physical function. Further research is needed to evaluate a delivery method for wider implementation of the program and to definitively test its effectiveness for improving function and other health benefits.

Resistance of Wheat Genotypes to Root-Lesion Nematode (Pratylenchus thornei) Can be Used to Predict Final Nematode Population Densities, Crop Greenness, and Grain Yield in the Field.

The root-lesion nematode Pratylenchus thornei is a major pathogen of wheat (Triticum aestivum) in many regions globally. Resistance of wheat genotypes to P. thornei can be determined from final nematode population densities in glasshouse experiments but combining results across multiple experiments presents challenges. Here, we use a factor analytic method for multiexperiment analysis of final population densities of P. thornei for 1,096 unique wheat genotypes in 22 glasshouse experiments. The resistance to P. thornei of the genotypes was effectively represented by a two-factor model with rotation of the axes to a principal components solution. Principal axes 1 and 2 (PA1 and PA2) accounted for 79 and 11% of the genetic variance, respectively, over all experiments. Final population densities of P. thornei as empirical best linear unbiased predictors (PA[1+2]-eBLUPs) from the combined glasshouse experiments were highly predictive (P < 0.001) of final nematode population densities in the soil profile, crop canopy greenness (normalized difference vegetation index), and grain yield of wheat genotypes in P. thornei-infested fields in the Australian subtropical grain region. Nine categories of resistance ratings for wheat genotypes from resistant to very susceptible were based on subdivision of the range of PA(1+2)-eBLUPs for use in growers' sowing guides. Nine genotypes were nominated as references for future resistance experiments. Most (62%) Australian wheat genotypes were in the most susceptible three categories (susceptible, susceptible to very susceptible, and very susceptible). However, resistant germplasm characterized in this study could be used in plant breeding to considerably improve the overall resistance of Australian wheat crops.

Impact of oxygen concentration on adult murine pre-antral follicle development in vitro and the corresponding metabolic profile.

Oxygen concentration during in vitro culture has a significant effect on the physiology of embryos, altering metabolic profile and developmental outcome. Although atmospheric oxygen has been used routinely for the culture of ovarian follicles, oxygen concentration may also be critical for follicle growth but the optimal concentration has not been determined. In this study, mechanically isolated primary and secondary follicles (80-140 µm diameter) from adult mouse ovaries were cultured in serum-free conditions for 8 days in either 5 or 20% oxygen to determine growth (follicular diameter), morphology and viability. For each oxygen concentration, half of the medium was replaced on Days 2, 4 and 6 or on Day 4 only. In the latter group, metabolic analysis of spent follicular culture media was performed by (1)H-NMR. The proportion of viable, growing follicles was significantly (P < 0.0001) higher in 5% than in 20% oxygen (59% versus 8%). Reducing the frequency of medium replacement during culture in 5% oxygen resulted in significantly (P < 0.001) more viable follicles (79 versus 46%). In 20% oxygen, poor follicular viability was observed irrespective of the frequency of medium replacement (8 and 10% respectively). Metabolic profiles showed marked differences in amino acid and carbohydrate utilization with respect to both oxygen concentration and between Days 4 and 8 of development. Metabolites which significantly discriminated between oxygen concentration at both time points were glucose consumption, lactate utilization, alanine, alanyl-glutamine, leucine and proline. In conclusion, the poor in vitro follicular development previously observed in minimal culture conditions may reflect the use of 20% oxygen. Frequent medium replenishment is not necessary and does not overcome the detrimental effect of high oxygen on follicle viability. Further optimization of culture conditions would benefit from metabolic analyses and the use of 5% oxygen should be tested further for impact on functional aspects of follicle culture such as steroid production which is currently unknown.

A prospective controlled study in the prevalence of posttraumatic headache following mild traumatic brain injury.

OBJECTIVE: To establish the prevalence of post traumatic headache, persisting at 3 months following minor traumatic brain injury. DESIGN: A prospective controlled study of patients admitted with a diagnosis of mild traumatic brain injury and matched orthopedic controls over 12 months during 2004. SETTING: A level two inner city Emergency Department in Sydney, Australia. PATIENTS: One hundred eligible sequential admissions with mild traumatic brain injury as defined by American Congress of Rehabilitation Medicine, 1993, and 100 matched minor injury controls with nondeceleration injuries. INTERVENTIONS: Subjects were part of a study on prediction of postconcussive syndrome and had neuropsychological tests, balance test and pain recordings taken at the time of injury, at 1 month and at 3 months post injury. OUTCOME MEASURES: Main measures were the reporting of headache "worse than prior to the injury" and concordant with the definition of Posttraumatic Headache according to International Headache Society Classification of Headache Disorders 2003. RESULTS: 15.34% of those with minor head injury continued to complain of perisistant posttraumatic headache at 3 months compared to 2.2% of the minor injury controls. CONCLUSIONS: To the authors' knowledge this is the first controlled prospective study in the prevalence of posttraumatic headache following mild traumatic brain injury.

The diagnostic accuracy of the Revised Westmead PTA Scale as an adjunct to the Glasgow Coma Scale in the early identification of cognitive impairment in patients with mild traumatic brain injury.

BACKGROUND: Assessment of patients with mild traumatic brain injury (mTBI) is predominantly done using the Glasgow Coma Scale (GCS). While the GCS is universally accepted for assessment of severity of traumatic brain injury, it may not be appropriate to rely on the GCS alone when assessing patients with mTBI in prehospital settings and emergency departments. OBJECTIVE: To determine whether administering the Revised Westmead Post-traumatic Amnesia (PTA) Scale (R-WPTAS) in addition to the GCS would increase diagnostic accuracy in the early identification of cognitive impairment in patients with mTBI. METHODS: Data were collected from 82 consecutive participants with mTBI who presented to the emergency department of a level 1 trauma centre in Australia. A matched sample of 88 control participants who attended the emergency department for reasons other than head trauma was also assessed. All patients were assessed using the GCS, R-WPTAS and a battery of neuropsychological tests. RESULTS: Patients with mTBI scored poorly compared with control patients on all measures. The R-WPTAS showed greater concurrent validity with the neuropsychological measures than the GCS and significantly increased prediction of group membership of patients with mTBI with cognitive impairment. CONCLUSIONS: The R-WPTAS significantly improves diagnostic accuracy in identifying patients with mTBI who may be in PTA. Administration takes less than 1 min, and since early identification of a patient's cognitive status facilitates management decisions, it is recommended for routine use whenever the GCS is used.

Myofascial trigger point development from visual and postural stressors during computer work.

The mechanism of musculoskeletal pain underlying low level static exertions, such as those experienced during computer work, is poorly understood. It was hypothesized that static postural and visual stress experienced during computer work might contribute to trigger point development in the trapezius muscles, resulting in myofascial pain. A study was conducted to observe the development of myofascial trigger points while 16 female subjects used a computer under conditions of high and low postural and visual stress. Trigger point development was monitored via expert opinion, subject self-report, and electromyographic activity. Only the high visual stress conditions resulted in greater trigger point sensitivity as reported by subjects and the myofascial specialist. Cyclic trends in median frequency of the EMG signal were assessed for the trapezius muscle. When high visual stress was combined with low postural stress condition there were significantly fewer cycles (1.6 cycles) as compared to the condition of low visual and low postural stress (2.8 cycles), and the condition of high visual and high postural stress (3.5 cycles). These significant differences between conditions were found for the right trapezius but not for the left. The findings suggest that high visual stress may be involved in the development of the myofascial pain response.

Methadone and caries. Case reports.

Several cases of advanced tooth destruction from widespread severe carious lesions are presented where methadone syrup has been used intra-orally in a drug rehabilitation programme. Aetiological factors are discussed and suggestions made concerning treatment plans and social implications for these patients.

Diurnal visual changes in radial keratotomy: implications for visual standards. Refractive Surgery Study Group.

BACKGROUND: Diurnal variations in vision have been reported in radial keratotomy (RK) patients. Applicants to certain professions may meet an uncorrected vision standard at the time of testing but fail to meet that standard at another time. METHODS: Ten firefighter applicants who had undergone RK and nine normal subjects attended for two morning visits, and two afternoon visits. At each visit subjective refraction, uncorrected visual acuity, best-corrected visual acuity, automated refraction, and keratometry were measured for each eye. Monocular contrast sensitivity was measured using the Pelli-Robson chart with and without a glare source (brightness acuity tester, BAT) and for both natural and dilated pupils. RESULTS: The RK group showed a significant myopic shift from morning to afternoon (mean = -0.41 +/- 0.33 D; t = 3.92, p = 0.004), which was well correlated (r = -0.86) with significant steepening of the corneal curvature (mean = +0.41 +/- 0.36 D; t = -3.65, p = 0.005). The controls showed no change in either refractive error (mean change = +0.06 +/- 0.42 D) or corneal curvature (mean change = +0.05 +/- 0.08 D). No significant difference in corrected visual acuity or contrast sensitivity was found between the RK and control groups for natural pupils. For dilated pupils, the RK patients showed significantly poorer log contrast sensitivity both with and without glare (RK mean = 1.49 +/- 0.11; control mean = 1.67 +/- 0.11; t = 3.21, p = 0.005). All RK subjects met the firefighter visual acuity standard on the initial visit, three subjects did not meet the standard at an afternoon examination. DISCUSSION: We propose that, if RK applicants are to be considered for employment, existing visual standards be amended to include visual acuity testing in both the early morning and late afternoon. Clinicians and agencies should also be aware that contrast sensitivity may be reduced at low light levels.

Quality of life issues in patients dying from haematological diseases.

Patients with haematological diseases do not have ready access to hospice services in South Australia. They remain in close contact with a specialist haematology or oncology unit, and are more likely than are patients with solid tumours to receive intensive therapy during a terminal admission. The course of the final month of life was compared for three groups of patients suffering from colorectal cancer, non-Hodgkins lymphoma and acute leukaemia by a review of hospital records. All leukaemia patients died in hospital and few received a palliative care consultation. Measures of symptom control and quality of life are not recorded for these patients. It seems probable that adults with acute leukaemia will continue to die in hospital. Some of the lessons learnt from hospice practice may be appropriately applied in hospital for those patients.

Does the presbyopic visual system adapt to contact lenses?

We studied whether task performance improves during the initial wearing period of selected presbyopic contact lens corrections. In three previous studies significant decreases in performance on three selected tasks were measured before and after initial wearing periods to monovision contact lenses (N = 18, 8 weeks of wear), concentric bifocal lenses (N = 32, 8 weeks), and diffractive and monovision lenses (N = 20, 3 weeks). In each study, the control condition was distance contact lenses with reading spectacles. The decreases in performance speed ranged from 2 to 15% compared to control. In this study, we retrospectively analyze the data to determine whether the task performance decreases relative to control were significantly different after the initial wearing period than at the time of dispensing--i.e., did measures of task performance show an adaptation to the presbyopic contact lens correction? Performance adaptation on each task and for each study was analyzed statistically using the Wilcoxon matched pair signed rank test of each subject's mean performance differences (test vs. control condition) at dispensing compared to the performance at the end of the wearing period. There was no improvement in task performance with monovision or diffractive bifocal lenses. However, we found significant improvements in task performance with concentric bifocal lenses (p < 0.05). Measures of visual acuity and stereoacuity did not improve with these lenses during the studied wearing period. Thus, these basic visual skills did not adapt. The ability of patients to learn how to use reduced visual acuity to perform complex tasks is a possible explanation for the improved task performance with concentric bifocal lenses compared to control.

Vision problems at video display terminals: a survey of optometrists.

One thousand three hundred seven optometrists responded (25.3 percent response rate) to a mail questionnaire concerning VDT patients in their practice. On the average, 14.25 percent of optometric patients present with symptoms primarily associated with use of the VDT, or almost 10 million examinations annually when projected to the U.S. population. A majority (55.3 percent) reported that their VDT patients have symptoms that are different than other near point workers, especially as related to glare, lighting, unique viewing conditions and spectacle requirements, and the greater frequency and severity of symptoms. They judged that they were unable to arrive at a confident diagnosis and treatment plan for 20.87 percent of VDT patients, which was significantly more than the 14.05 percent for non-VDT patients. Uncorrected refractive errors, accommodative disorders, irritated eyes, binocular vision disorders, and spectacle design problems were the most frequently cited diagnoses. On the average, 39.3 percent of their VDT patients receive a special VDT prescription or spectacle design that is different than they would require for other daily activities. They judged that 36.8 percent of the symptoms were related to visual environmental factors, primarily glare, lighting, screen resolution and work arrangement. The best way to resolve symptoms for VDT workers is to provide thorough vision examination and treatment in conjunction with diagnosis and treatment of visual environmental problems.

Vision and task performance with monovision and diffractive bifocal contact lenses.

We measured vision and task performance on 26 presbyopes, ages 46 to 65 years, fitted with diffractive bifocal contact lenses (BFCL) and monovision contact lenses (MVCL). Distance contact lenses combined with reading spectacles (DCL) served as the control condition. Twenty subjects completed the 6-week study. All subjects wore BFCL and MVCL daily for a period of 3 weeks each. Performance times for three near tasks were 6 to 8% longer with BFCL compared with DCL and 2 to 6% longer for MVCL compared with DCL. There were significant reductions in distance visual acuity with BFCL (0.4 to 1.5 Snellen lines) and MVCL (0.5 to 0.8 Snellen lines) compared to DCL. At the conclusion of the study, given a choice between BFCL and MVCL, 2 of the 20 subjects chose to continue wearing BFCL, whereas 18 of the 20 subjects chose MVCL. Our results show greater visual compromise and decreased task performance with BFCL and MVCL compared to DCL and greater patient preference for MVCL.

Occupational and environmental disorders of the special senses.

Occupational hazards to vision, hearing, balance, olfaction, and taste typically constitute a small fraction of specialty medical practices in ophthalmology and otolaryngology. With the possible exception of noise-related hearing loss and VDT eye hazards, the scientific literature regarding these hazards tends to be scattered and variably accessible to occupational medicine practitioners. It is hoped that the current review will heighten the appreciation of these hazards among both generalists and specialists, and will encourage future documentation and reporting of this interesting group of disorders.

Task and visual performance with contact lenses and spectacles.

Previous studies found task and vision performance differences between presbyopic contact lens corrections and distant contact lenses combined with reading spectacles. The present study was designed to compare task and vision performance with single vision contact lenses and spectacles. Eighteen soft (SCL) and seventeen rigid gas permeable (RGP) successful contact lens wearers were examined and fitted with CR-39 spectacles (SPEX) which corrected their distance vision. Their occupational task performance and visual acuity (high contrast, low contrast, low contrast with glare) were measured while they wore their contact lenses and spectacles. The tasks included putting pointers in straws, filing cards in a box, counting letters on a photograph of a VDT screen, and a distance/near fixation task. Visual acuity scores were lower with SCL than with SPEX. Low contrast visual acuity with glare was reduced by 1.36 letters on a 5-letter row (p less than 0.05) for SCL compared to SPEX. No statistically significant differences in performance times were measured between contact lenses and spectacles. None of the error performance differences were statistically significant; however, more errors were made on each occupational task with soft contact lenses compared to spectacles. The findings suggest nearly equivalent task and visual performance with properly prescribed RGP contact lenses and spectacles, and minimal performance decrements with SCL compared to spectacles.

Noninvasive assessment of the visual system and ophthalmic and visual optics: an introduction to the joint vision features.

This is an introduction to the joint feature on noninvasive assessment of the visual system and ophthalmic and visual optics.

Task and visual performance with concentric bifocal contact lenses.

We evaluated the effects of concentric simultaneous vision bifocal contact lenses on task performance, visual acuity, and stereopsis. Forty extensively screened presbyopes were fitted with CIBA Spectrum center-near bifocal contact lenses (BCL) and with distant contact lenses combined with reading spectacles (DCL) which served as the control. Thirty-two subjects completed the 8-week study. At dispensing and after 8 weeks of regular BCL wear, performance times with BCL were significantly greater than with DCL for all three near tasks. BCL generally resulted in more errors per trial. Visual acuities with BCL were reduced significantly by 0.8 to 1.4 acuity lines compared to DCL. Stereopsis was reduced significantly by 32 to 36 sec arc with BCL compared to DCL at both measurement sessions. It is likely that the decreased task performance with the simultaneous vision BCL is caused by the decreased visual acuity with these lenses. Nonetheless, 27 patients (58.7% of those selected to be fitted; 67.5% of those who were fitted) chose to wear the BCL on a regular basis at the study conclusion. Thus, even though BCL reduced task and visual performance, thoroughly screened and properly fitted presbyopic patients can become satisfied BCL wearers. However, the reduced task and visual performance with BCL should be considered when evaluating prospective BCL candidates.

Patient response to concentric bifocal contact lenses.

We evaluated the visual results and success rate with a center-near concentric simultaneous vision bifocal contact lens. Forty subjects (screened from 175 presbyopic applicants) entered the study and were fitted with the CIBA Spectrum bifocal lenses (BCL) and also with single vision distance contact lenses combined with reading glasses (DCL). Visual acuity and stereoacuity measurements were made at dispensing and after 8 weeks of regular bifocal contact lens wear. At both times, visual acuity measurements with BCL were significantly reduced by 1-1.5 lines compared to DCL. Stereoacuity was reduced by 32-36" with BCL compared to DCL. Thirty-two patients completed the study and 27 chose to continue wearing BCL after completion of the study. None of the subjects had adverse corneal findings or problems of discomfort. The primary reason for BCL discontinuation was blurred vision. The data was retrospectively analyzed to identify risk factors for discontinuance--none were significant.