One-Year Follow-Up of a Vocal Hygiene Program for School-Age Children.

OBJECTIVE: This study investigated the effects of a school-based vocal hygiene education program "Green Voice for School" on promoting knowledge of healthy voice use for primary school students. METHODS: Thirty-nine grade 4 and 5 students from local primary schools participated in the "Green Voice for School" program. Students received 6 weekly vocal hygiene training sessions with the aim of enhancing their voice care knowledge. Their voice care knowledge was assessed by a 15-item questionnaire. Students' voice care knowledge was examined before training, immediately after, and 1 year after completion of the program. RESULTS: Students showed significant improvements in their voice care knowledge immediately after they received the vocal hygiene training sessions. Such improvements were maintained 1 year after the students completed training. CONCLUSIONS: The results suggest that "Green Voice for School", a school-based vocal hygiene education program, can be effective in promoting long-term improvements of voice care knowledge in school-age children.

The effects of aging on postural control and selective attention when stepping down while performing a concurrent auditory response task.

PURPOSE: To investigate the effects of aging on postural control and cognitive performance in single- and dual-tasking. METHODS: A cross-sectional comparative design was conducted in a university motion analysis laboratory. Young adults (n = 30; age 21.9 ± 2.4 years) and older adults (n = 30; age 71.9 ± 6.4 years) were recruited. Postural control after stepping down was measured with and without performing a concurrent auditory response task. Measurement included: (1) reaction time and (2) error rate in performing the cognitive task; (3) total sway path and (4) total sway area after stepping down. RESULTS: Our findings showed that the older adults had significantly longer reaction times and higher error rates than the younger subjects in both the single-tasking and dual-tasking conditions. The older adults had significantly longer reaction times and higher error rates when dual-tasking compared with single-tasking, but the younger adults did not. The older adults demonstrated significantly less total sway path, but larger total sway area in single-leg stance after stepping down than the young adults. The older adults showed no significant change in total sway path and area between the dual-tasking and when compared with single-tasking conditions, while the younger adults showed significant decreases in sway. CONCLUSION: Older adults prioritize postural control by sacrificing cognitive performance when faced with dual-tasking.

Anaesthetic considerations for strabismus surgery in children and adults.

Strabismus correction surgery is the most common eye operation in children. Adults have approximately a 4% lifetime risk of developing strabismus. Current treatment options include pharmacological injection of botulinum toxin or bupivacaine, conventional corrective surgery, adjustable suture surgery and minimally invasive surgery. Repeated surgery is common as each operation has a 60%-80% chance of successful correction. The benefits of early surgical correction in large-angle strabismus in children outweigh the risks of anaesthesia. General anaesthesia is suitable for patients of all age groups, for complicated or repeated surgery, and bilateral eye procedures. Regional ophthalmic block reduces the incidence of oculocardiac reflex and emergence agitation, and provides postoperative analgesia, but requires a cooperative patient as many experience discomfort. Topical anaesthesia has been used in pharmacological injection, minimally invasive surgery, uncomplicated conventional strabismus surgery and some adjustable suture strabismus surgery. Its use, however, is only limited to cooperative adult patients. Prophylactic antiemesis with both ondansetron and dexamethasone is recommended, especially for children. A multimodal analgesia approach, including paracetamol, intravenous non-steroidal anti-inflammatory drugs, topical local anaesthetic and minimal opioid usage, is recommended for postoperative analgesia, while a supplementary regional ophthalmic block is at the discretion of the team.

Compensation mechanism in tumor cell migration: mesenchymal-amoeboid transition after blocking of pericellular proteolysis.

Invasive tumor dissemination in vitro and in vivo involves the proteolytic degradation of ECM barriers. This process, however, is only incompletely attenuated by protease inhibitor-based treatment, suggesting the existence of migratory compensation strategies. In three-dimensional collagen matrices, spindle-shaped proteolytically potent HT-1080 fibrosarcoma and MDA-MB-231 carcinoma cells exhibited a constitutive mesenchymal-type movement including the coclustering of beta 1 integrins and MT1-matrix metalloproteinase (MMP) at fiber bindings sites and the generation of tube-like proteolytic degradation tracks. Near-total inhibition of MMPs, serine proteases, cathepsins, and other proteases, however, induced a conversion toward spherical morphology at near undiminished migration rates. Sustained protease-independent migration resulted from a flexible amoeba-like shape change, i.e., propulsive squeezing through preexisting matrix gaps and formation of constriction rings in the absence of matrix degradation, concomitant loss of clustered beta 1 integrins and MT1-MMP from fiber binding sites, and a diffuse cortical distribution of the actin cytoskeleton. Acquisition of protease-independent amoeboid dissemination was confirmed for HT-1080 cells injected into the mouse dermis monitored by intravital multiphoton microscopy. In conclusion, the transition from proteolytic mesenchymal toward nonproteolytic amoeboid movement highlights a supramolecular plasticity mechanism in cell migration and further represents a putative escape mechanism in tumor cell dissemination after abrogation of pericellular proteolysis.

Fractal Dimension Analysis of Transient Visual Evoked Potentials: Optimisation and Applications.

PURPOSE: The visual evoked potential (VEP) provides a time series signal response to an external visual stimulus at the location of the visual cortex. The major VEP signal components, peak latency and amplitude, may be affected by disease processes. Additionally, the VEP contains fine detailed and non-periodic structure, of presently unclear relevance to normal function, which may be quantified using the fractal dimension. The purpose of this study is to provide a systematic investigation of the key parameters in the measurement of the fractal dimension of VEPs, to develop an optimal analysis protocol for application. METHODS: VEP time series were mathematically transformed using delay time, τ, and embedding dimension, m, parameters. The fractal dimension of the transformed data was obtained from a scaling analysis based on straight line fits to the numbers of pairs of points with separation less than r versus log(r) in the transformed space. Optimal τ, m, and scaling analysis were obtained by comparing the consistency of results using different sampling frequencies. The optimised method was then piloted on samples of normal and abnormal VEPs. RESULTS: Consistent fractal dimension estimates were obtained using τ = 4 ms, designating the fractal dimension = D2 of the time series based on embedding dimension m = 7 (for 3606 Hz and 5000 Hz), m = 6 (for 1803 Hz) and m = 5 (for 1000Hz), and estimating D2 for each embedding dimension as the steepest slope of the linear scaling region in the plot of log(C(r)) vs log(r) provided the scaling region occurred within the middle third of the plot. Piloting revealed that fractal dimensions were higher from the sampled abnormal than normal achromatic VEPs in adults (p = 0.02). Variances of fractal dimension were higher from the abnormal than normal chromatic VEPs in children (p = 0.01). CONCLUSIONS: A useful analysis protocol to assess the fractal dimension of transformed VEPs has been developed.

Retinal vessel diameter and open-angle glaucoma: the Blue Mountains Eye Study.

PURPOSE: To examine the relationship between open-angle glaucoma (OAG) and retinal vessel diameter among baseline participants in the Blue Mountains Eye Study. DESIGN: Population-based cross-sectional study. PARTICIPANTS: The study included 3654 persons older than 49 years, representing 82.4% of permanent residents living in an area west of Sydney. METHODS: Participants had a detailed eye examination, including automated perimetry and stereo optic disc photography. A computer-assisted program measured retinal vessel diameters from digitized photographs of right eyes. MAIN OUTCOME MEASURES: Open-angle glaucoma was diagnosed from matching visual field defects and optic disc cupping, without reference to intraocular pressure (IOP) level. Ocular hypertension was defined as IOP of >21 mmHg in either eye, without matching glaucomatous optic disc and field changes. Average retinal vessel diameters, measured from right eyes, were summarized as arteriolar and venular equivalents. The lowest quintile of the arteriolar equivalent or arteriole-to-venule ratio was used to define generalized retinal arteriolar narrowing. RESULTS: The study included 3314 participants, after excluding those with incomplete data or nonglaucomatous optic nerve disease. Of persons included, 59 (1.8%) had evidence of glaucomatous damage affecting the right eye, 3065 (92.5%) had no damage to either eye, and 163 (4.9%) had ocular hypertension. Right eyes with glaucomatous damage had significantly narrower retinal arteriolar diameters (183+/-2.6 microm) than eyes without glaucoma (194+/-0.4 microm, P = 0.0001) or eyes with ocular hypertension (195+/-1.6 microm, P = 0.0002), after adjusting for age, mean arterial blood pressure, and other confounding variables, including refraction. Right eyes with glaucomatous damage were at least 2 times more likely to have generalized retinal arteriolar narrowing than eyes without glaucoma (odds ratio, 2.7; 95% confidence interval, 1.5-4.8). CONCLUSIONS: These population-based data suggest that generalized retinal arteriolar narrowing, an indicator of localized vascular change, is significantly associated with optic nerve damage caused by OAG. It is not clear whether such a retinal arteriolar change reflects an ischemic process leading to optic nerve damage or results from loss of retinal neurons secondary to glaucoma.

Impact of current and past blood pressure on retinal arteriolar diameter in an older population.

OBJECTIVE: To examine the effects of current and past blood pressure on retinal arteriolar diameter in a general older population. DESIGN: Cross-sectional and longitudinal studies. SETTING: Population-based cohort study of older residents from an area west of Sydney, Australia. PARTICIPANTS: Two thousand three hundred and thirty-five individuals (n = 2335) (aged > or = 54 years) who attended the 5-year follow-up Blue Mountains Eye Study during 1997-99. MAIN OUTCOME MEASURES: A computer-assisted method measured vessel diameters from digitized right eye retinal photographs. The narrowest quintile of central retinal arteriolar equivalent or arteriole-to-venule ratio (AVR) defined generalized arteriolar narrowing. Blood pressure was measured using a mercury sphygmomanometer. RESULTS: After simultaneous adjustment for age, sex, body mass index, smoking and current or past blood pressure, elevated levels of both current and past blood pressure were associated with narrower retinal arterioles [Ptrend = 0.009 and 0.007 for current and past systolic blood pressure (SBP), respectively] and lower AVR [Ptrend = 0.001 and 0.0009 for current and past diastolic blood pressure (DBP), respectively]. Generalized arteriolar narrowing was associated with both current blood pressure [adjusted odds ratio (OR) 2.4, 95% confidence interval (CI) 1.5-3.8 for the highest versus lowest quintile of current DBP] and past blood pressure (adjusted OR 1.7, 95% CI 1.1-2.6, for the highest versus lowest quintile of past DBP). Hypertension duration or control status at baseline had no additional effect on arteriolar diameter after adjusting for current blood pressure. CONCLUSIONS: Our data document the independent effects of both current and past blood pressure on small vessel calibre in the retina, suggesting that retinal arteriolar narrowing may result from the cumulative effects of long-standing hypertension.

Relationships between age, blood pressure, and retinal vessel diameters in an older population.

PURPOSE: To describe the cross-sectional relationships between age, blood pressure (BP), and quantitative measures of retinal vessel diameters in an older Australian population. METHODS: Retinal photographs from right eyes of participants (n = 3654, aged 49+ years) in the Blue Mountains Eye study taken during baseline examinations (1992-1994) were digitized. The width of all retinal vessels located 0.5 to 1.0 disc diameters from the disc margin was measured by a computer-assisted method. Summarized estimates for central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE) represent average retinal vessel diameters. The arteriole-to-venule ratio (AVR) was calculated. Associations between age and BP and CRAE, CRVE, and AVR were assessed with generalized linear models. RESULTS: Retinal vessel diameters decreased with increasing age in both men and women. CRAE and CRVE decreased by 4.8 microm and 4.1 microm, respectively, per decade increase in age, after adjusting for sex and mean arterial blood pressure. Mean AVR declined by 0.01 for each increasing decade of age, until 79 years. After adjustment for age, sex, smoking, and body mass index, CRAE, CRVE and AVR were all significantly and inversely associated with BP. For every 10-mm Hg increase in mean arterial blood pressure, AVR decreased by 0.012 and CRAE and CRVE decreased by 3.5 microm and 0.96 microm, respectively. CONCLUSIONS: Retinal arteriolar and venular diameters narrow with increasing age, and these parameters are inversely related to BP, independent of age, gender, and smoking. The findings are consistent with those from the Atherosclerosis Risk in Communities Study suggesting that decreased retinal vessel diameters may reflect microvascular damage from elevated blood pressure.

Confused and disturbed behavior in the elderly following silent frontal lobe infarction.

It is unclear whether silent frontal lobe infarction is truly asymptomatic; frontal behavioral syndromes following strokes have rarely been reported. We studied 12 elderly patients with silent frontal lobe infarction who were exhibiting confused and disturbed behavior. Ten were male and two female; their ages ranged from 68 to 79 (mean 78). Three groups of symptom clusters emerged: changes in mood and emotional behavior, cognitive deterioration with minor psychiatric symptoms, and a confusional state. When related to the CT scan location, three regions were identified: predominantly orbitofrontal, deep white matter and caudate, and border-zones, respectively. These findings were related to what is known about the neuroanatomic location of the lesions and the role of the frontal subcortical circuitry in relation to behavior. The different manifestations could be explained by damage to the frontal lobe or interruption of the complex frontal subcortical circuits.

Beneficial effect of treatment for strabismus in patients with bilaterally poor vision, who cannot see their strabismus.

METHODS: Retrospective case note review of management of patients with bilaterally severely reduced vision presenting with symptomatic strabismus. RESULTS: There were 10 females and 7 males, mean age at treatment was 36 years, range 19 to 74 years. Thirteen patients had an exotropia ranging from 20 to 90(Δ) (mean 52(Δ)). Four had an esotropia ranging from 30 to 70(Δ) (mean 53(Δ)). Vision in each eye ranged from 6/24 Snellen to light perception, except for one patient with Usher's syndrome who had grossly restricted visual fields and vision of 6/12 and 6/36. The etiology was retinitis pigmentosa in 5 patients; 3 had cone dystrophy, 2 were high myopes. Other etiologies included CMV retinitis in both eyes secondary to HIV, bilateral optic atrophy post craniopharyngioma, and cortical visual impairment. All patients were unable to see well enough to assess their strabismus but were aware of its presence from family members and friends and wished improvement. Eleven patients underwent botulinum toxin injections; 2 of these then proceeded to surgery. A total of 8 patients had surgery. Post-operative angles ranged from 6(Δ) to 25(Δ) of esotropia. Five patients continue with maintenance toxin. Follow-up ranged from 3 months to 15 years. DISCUSSION/CONCLUSIONS: This is the first report of patients with bilaterally severely reduced vision requesting treatment for strabismus that they were unable to see for themselves. All patients were pleased they had undergone treatment for their strabismus despite being unable to see the outcome.

Intraconal superior ophthalmic vein embolisation for carotid cavernous fistula.

A 53-year-old man presented with a longstanding carotid cavernous fistula that could not be embolised completely via the femoral route. A superior ophthalmic vein approach was necessary; however, the vein was thrombosed anteriorly and only intraconal cannulation was possible. The vein was accessed via a superior lid crease approach and the fistula successfully embolised. Whilst utilising the superior ophthalmic vein is well described in the literature, to our knowledge, needing to access the intraconal portion of the vein has not previously been reported.

Perisinusoidal B cells in the bone marrow participate in T-independent responses to blood-borne microbes.

Mature recirculating B cells are generally assumed to exist in follicular niches in secondary lymphoid organs, and these cells mediate T-dependent humoral immune responses. We show here that a large proportion of mature B lymphocytes occupy an anatomically and functionally distinct perisinusoidal niche in the bone marrow. Perisinusoidal B cells circulate freely, as revealed by parabiosis studies. However, unlike their counterparts in the follicular niche, these cells are capable of being activated in situ by blood-borne microbes in a T-independent manner to generate specific IgM antibodies. The bone marrow represents a unique type of secondary lymphoid organ in which mature B cells are strategically positioned in the path of circulating microbes.

Bone marrow is a major reservoir and site of recruitment for central memory CD8+ T cells.

Normal bone marrow (BM) contains T cells whose function and origin are poorly understood. We observed that CD8+ T cells in BM consist chiefly of CCR7+ L-selectin+ central memory cells (TCMs). Adoptively transferred TCMs accumulated more efficiently in the BM than naive and effector T cells. Intravital microscopy (IVM) showed that TCMs roll efficiently in BM microvessels via L-, P-, and E-selectin, whereas firm arrest required the VCAM-1/alpha4beta1 pathway. alpha4beta1 integrin activation did not depend on pertussis toxin (PTX)-sensitive Galphai proteins but was reduced by anti-CXCL12. In contrast, TCM diapedesis did not require CXCL12 but was blocked by PTX. After extravasation, TCMs displayed agile movement within BM cavities, remained viable, and mounted potent antigen-specific recall responses for at least two months. Thus, the BM functions as a major reservoir for TCMs by providing specific recruitment signals that act in sequence to mediate the constitutive recruitment of TCMs from the blood.

Lacunar thalamic stroke proclivity for falls.

Small ischaemic lesions strategically placed could give rise to specific clinical manifestations depending on the location and size of the lesion. We present the case of five patients with imbalance and falls with no other neurological findings. The computed tomographic scan showed a lacunar infarct in the right or left thalamus. The tendency to fall may complicate rehabilitation. The possible physiological mechanisms are discussed.

Does hormone replacement therapy influence retinal microvascular caliber?

Previous population-based data suggest that retinal arteriolar diameter is wider in women than in men. Estrogen exposures could account for this difference. To evaluate the effects of HRT on small blood vessels, we assessed the relationship between use of hormone replacement therapy (HRT) and retinal microvascular diameter in older women in the Blue Mountains Eye Study baseline population (n = 1993, age >/= 49 years). Information on HRT use was recorded by trained interviewers. A computer-assisted program measured retinal vessel diameters from digitized photographs. Average arteriolar diameter was calculated as the central retinal arteriolar equivalent (CRAE); the lowest quintile of CRAE was considered generalized arteriolar narrowing. Of the 1897 women with complete data, 79 (4%) were premenopausal and 315 (17%), 224 (12%), and 1279 (67%) were current, past, and never HRT users, respectively. Among women aged < 65 years, multivariate-adjusted mean CRAE for the four groups was 196, 198, 201, and 200 microm (P < 0.0001), respectively. Among postmenopausal women >/= 65 years, multivariate-adjusted mean CRAE was 187, 188, 191 microm (P < 0.0001), respectively, for current, past, and never users. Current HRT users were 40% more likely than never users to have generalized arteriolar narrowing (95% confidence interval 1.0-2.1). It appears that the use of HRT in older women may not have any long-term vasodilatory effects on retinal arterioles. These data do not support our hypothesis that exogenous estrogen exposures account for observed wider retinal arteriolar diameters in women.

Hypertensive retinal vessel wall signs in a general older population: the Blue Mountains Eye Study.

To describe cross-sectional relations between hypertension and retinal vessel wall signs in an older white population. These signs were defined from fundus photographs in 3654 Blue Mountains Eye Study participants > or =49 years of age. Focal arteriolar narrowing and arteriovenous nicking were graded through the use of standard protocol. Photographs were digitized to measure retinal vessel diameters. Average arteriolar diameter, summarized as central retinal arteriolar equivalent and arteriole-to-venule ratio, were used as indexes of generalized arteriolar narrowing. Blood pressure was measured with the use of a mercury sphygmomanometer. Hypertension was defined through the use of antihypertensive medications, systolic blood pressure > or =160 mm Hg, or diastolic blood pressure > or =95 mm Hg. Hypertension was categorized as controlled (using medication, normal blood pressure), uncontrolled (using medication, high blood pressure), or untreated (not using medication). Hypertensive subjects had higher prevalence of all retinal microvascular signs. After adjusting for age, gender, body mass index, and smoking, persons with controlled (18.2%), uncontrolled (13.8%), or untreated hypertension (13.8%) were significantly more likely than normotensive subjects (54.2%) to have (a) lower central retinal arteriolar equivalent: adjusted odds ratios 1.5, (95% CI, 1.1 to 1.9), 2.1 (1.6 to 2.7), and 2.1 (1.6 to 2.7), respectively, and lower arteriole-to-venule ratio: 1.3 (1.0 to 1.6), 1.4 (1.1 to 1.8), and 1.7 (1.3 to 2.2), respectively; (b) focal arteriolar narrowing: 1.3 (0.9 to 1.9), 2.2 (1.5 to 3.2), and 2.5 (1.8 to 3.6), respectively; and (c) arteriovenous nicking: 1.3 (0.9 to 1.8), 2.3 (1.6 to 3.2), and 1.9 (1.3 to 2.7), respectively. Our findings demonstrate a strong relation between presence and severity of hypertension and retinal microvascular structural changes.

Computer-assisted retinal vessel measurement in an older population: correlation between right and left eyes.

This study assessed the correlation between computer-assisted retinal vessel measurements of right and left eyes, from subjects in a defined, community-based older population. Retinal photographs from participants in the Blue Mountains Eye Study were digitized. All retinal arterioles and venules located 0.5-1.0 disc diameters from the optic disc margin were identified and a computer program measured their diameters. Pearson correlation (R2) statistic was used to assess the correlation in a random subsample of 1546 images. Substantial correlation between right and left eye measurements was found for summary indices of retinal arterioles (R2 = 0.70) and venules (R2 = 0.77). Higher correlation was found for intragrader (R2 0.75-079) than for intergrader assessment (R2 0.67-0.72). Moderate correlation was found in arteriole-to-venule ratio assessed by the same (R2 = 0.57) or different (R2 = 0.52) graders. Measurements from one eye can thus adequately represent the retinal vessel diameters of a person.