Relationship between chronic stress and carotid intima-media thickness (IMT) in elderly Alzheimer's disease caregivers

The stress associated with providing care for a spouse diagnosed with Alzheimer's disease can have adverse effects on cardiovascular health. One potential explanation is that chronic caregiving stress may contribute to the development of atherosclerosis. The purpose of this study was to determine whether the duration that one has provided care is associated with the degree of atherosclerotic burden, as measured by carotid artery intima-media thickness (IMT). One hundred and ten Alzheimer caregivers [mean age 74 ± 8 (SD) years, 69% female] underwent in-home assessment of carotid artery IMT via B-mode ultrasonography. Data regarding medical history, blood pressure, and multiple indicators of caregiving stress were also collected. Multiple regression indicated that duration of care was positively associated with IMT measured in the internal/bifurcation segments of the carotid artery (β = 0.202, p = 0.044) independent of risk factors such as age, gender, body mass index, smoking history, sleep quality, hypertension status, and caregiving stressors. Duration of care was positively associated with IMT in the common carotid artery, but the relationship was not significant. These findings provide more evidence of the link between chronic caregiving stress and cardiovascular disease and indicate that enduring the experience of caregiving over a period of years might be associated with atherosclerotic burden.

Prospective Study of Foveal Thickness Alterations after Cataract Surgery Assessed by Optical Coherence Tomography

Background/Aims: To evaluate the alterations of mean foveal thickness (MFT) and visual acuity (VA) outcomes after uncomplicated cataract surgery in different groups of patients. Methods: This study included eyes of consecutive patients who underwent cataract surgery between November 2007 and June 2009. The patients included in the study were divided into 4 groups, as follows: history-free patients, patients with diabetes mellitus without macular involvement at baseline, patients with glaucoma, and patients with epiretinal membrane (ERM). Preoperatively and at 1, 3 and 6 months postoperatively, patients were evaluated for MFT by optical coherence tomography at the central 1-mm macular zone and for logarithm of the minimum angle of resolution best spectacle-corrected VA (BSCVA). Results: A total of 202 eyes were included in the study. MFT values demonstrated a statistically significant increase (p < 0.01) after cataract surgery in all groups at the first and third postoperative month. The history-free (p = 0.09) and glaucoma (p = 0.19) groups did not demonstrate a statistically significant difference in MFT values between the preoperative and 6-month measurements. MFT values 6 months after cataract surgery in the diabetes and ERM groups remained significantly higher (p < 0.01). Despite these findings, VA increased significantly (p < 0.01) in all groups at all postoperative follow-ups. Conclusions: MFT values increased significantly in all groups at the first and third months after cataract surgery. At 6 months, MFT values returned to preoperative levels in the history-free and glaucoma patients, while they remained significantly higher in the diabetic and ERM patients. Despite these macular alterations, BSCVA improved significantly after cataract surgery in all groups at all postoperative follow-ups.

Retinal thickness in Parkinson's disease

BACKGROUND: Visual symptoms are common in Parkinson's disease with studies consistently demonstrating reductions in visual acuity, contrast sensitivity, colour and motion perception as well as alterations in electroretinogram latencies and amplitudes. Optical coherence tomography can examine retinal structure non-invasively and retinal thinning has been suggested as a potential biomarker for neurodegeneration in Parkinson's disease. Our aim was to examine the retinal thickness of a cohort of Parkinson's disease subjects (and age-matched controls) to establish the practical utility of optical coherence tomography in a representative older Parkinson's disease group. METHODS: Fifty-one established Parkinson's disease subjects and 25 healthy controls were subjected to ophthalmological assessment and optical coherence tomography (Zeiss Stratus 3000™) of macular thickness and volume and retinal nerve fibre thickness around the optic nerve head. Twenty four percent of control and 20% of Parkinson's disease subjects were excluded from final analysis due to co-morbid ocular pathology. Further data was excluded either due to poor tolerability of optical coherence tomography or poor quality scans. RESULTS: Despite a reduction in both visual acuity and contrast sensitivity in the residual evaluable Parkinson's disease cohort, we did not detect any differences between the two study groups for any measures of retinal thickness, in contrast to previously published work. CONCLUSIONS: In addition to technical problems inherent in the evaluation, the lack of difference between Parkinson's disease and healthy control subjects suggests longitudinal studies, employing newer techniques, will be required to define the role of optical coherence tomography as a potential diagnostic biomarker.

Influence of Surface Roughness on Mechanical Properties of Two Computer-aided Design/Computer-aided Manufacturing (CAD/CAM) Ceramic Materials

SUMMARY The aim of this study was to evaluate the influence of surface roughness on surface hardness (Vickers; VHN), elastic modulus (EM), and flexural strength (FLS) of two computer-aided design/computer-aided manufacturing (CAD/CAM) ceramic materials. One hundred sixty-two samples of VITABLOCS Mark II (VMII) and 162 samples of IPS Empress CAD (IPS) were ground according to six standardized protocols producing decreasing surface roughnesses (n=27/group): grinding with 1) silicon carbide (SiC) paper #80, 2) SiC paper #120, 3) SiC paper #220, 4) SiC paper #320, 5) SiC paper #500, and 6) SiC paper #1000. Surface roughness (Ra/Rz) was measured with a surface roughness meter, VHN and EM with a hardness indentation device, and FLS with a three-point bending test. To test for a correlation between surface roughness (Ra/Rz) and VHN, EM, or FLS, Spearman rank correlation coefficients were calculated. The decrease in surface roughness led to an increase in VHN from (VMII/IPS; medians) 263.7/256.5 VHN to 646.8/601.5 VHN, an increase in EM from 45.4/41.0 GPa to 66.8/58.4 GPa, and an increase in FLS from 49.5/44.3 MPa to 73.0/97.2 MPa. For both ceramic materials, Spearman rank correlation coefficients showed a strong negative correlation between surface roughness (Ra/Rz) and VHN or EM and a moderate negative correlation between Ra/Rz and FLS. In conclusion, a decrease in surface roughness generally improved the mechanical properties of the CAD/CAM ceramic materials tested. However, FLS was less influenced by surface roughness than expected.

Differences in neointimal thickness between the adluminal and the abluminal sides of malapposed and side-branch struts in a polylactide bioresorbable scaffold: evidence in vivo about the abluminal healing process

The goal of this study was to describe the neointimal healing on the abluminal side (ABL) of malapposed (ISA) struts and nonapposed side-branch (NASB) struts in terms of coverage by optical coherence tomography (OCT) and in comparison with the adluminal side (ADL).

An Investigation of Two Ceramic Electron Conductors for Use in Solid Oxide Fuel Cell Anodes

Conducted work with two potential alternatives to Ni, La0.8Sr0.2Cr0.5Mn0.5 (LSCM) and Sr doped LaVO3 (LSV) to serve as the electron conductor in the anode of solid oxide fuel cells SOFCs.

Using Micro-Gravity Techniques to Map Alluvium Thickness and Pleistocene Location of the West Branch of the Susquehanna River Near Muncy, Pennsylvania

Laurentide glaciation during the early Pleistocene (~970 ka) dammed the southeast-flowing West Branch of the Susquehanna River (WBSR), scouring bedrock and creating 100-km-long glacial Lake Lesley near the Great Bend at Muncy, Pennsylvania (Ramage et al., 1998). Local drill logs and well data indicate that subsequent paleo-outwash floods and modern fluvial processes have deposited as much as 30 meters of alluvium in this area, but little is known about the valley fill architecture and the bedrock-alluvium interface. By gaining a greater understanding of the bedrock-alluvium interface the project will not only supplement existing depth to bedrock information, but also provide information pertinent to the evolution of the Muncy Valley landscape. This project determined if variations in the thickness of the valley fill were detectable using micro-gravity techniques to map the bedrock-alluvium interface. The gravity method was deemed appropriate due to scale of the study area (~30 km2), ease of operation by a single person, and the available geophysical equipment. A LaCoste and Romberg Gravitron unit was used to collect gravitational field readings at 49 locations over 5 transects across the Muncy Creek and Susquehanna River valleys (approximately 30 km2), with at least two gravity base stations per transect. Precise latitude, longitude and ground surface elevation at each location were measured using an OPUS corrected Trimble RTK-GPS unit. Base stations were chosen based on ease of access due to the necessity of repeat measurements. Gravity measurement locations were selected and marked to provide easy access and repeat measurements. The gravimeter was returned to a base station within every two hours and a looping procedure was used to determine drift and maximize confidence in the gravity measurements. A two-minute calibration reading at each station was used to minimize any tares in the data. The Gravitron digitally recorded finite impulse response filtered gravity measurements every 20 seconds at each station. A measurement period of 15 minutes was used for each base station occupation and a minimum of 5 minutes at all other locations. Longer or multiple measurements were utilized at some sites if drift or other externalities (i.e. train or truck traffic) were effecting readings. Average, median, standard deviation and 95% confidence interval were calculated for each station. Tidal, drift, latitude, free-air, Bouguer and terrain corrections were then applied. The results show that the gravitational field decreases as alluvium thickness increases across the axes of the Susquehanna River and Muncy Creek valleys. However, the location of the gravity low does not correspond with the present-day location of the West Branch of the Susquehanna River (WBSR), suggesting that the WBSR may have been constrained along Bald Eagle Mountain by a glacial lobe originating from the Muncy Creek Valley to the northeast. Using a 3-D inversion model, the topography of the bedrock-alluvium interface was determined over the extent of the study area using a density contrast of -0.8 g/cm3. Our results are consistent with the bedrock geometry of the area, and provide a low-cost, non-invasive and efficient method for exploring the subsurface and for supplementing existing well data.

Does bladder wall thickness decrease when obstruction is resolved?

The aim of the current study was to determine if sonographic bladder wall thickness diminishes after symptomatic obstruction is resolved in female patients after stress incontinence surgery.

Comparison of rebound tonometry with Goldmann applanation tonometry and correlation with central corneal thickness

BACKGROUND/AIMS: Rebound tonometry (RT) is performed without anaesthesia with a hand held device. The primary aim was to compare RT with Goldmann applanation tonometry (GAT) and to correlate with central corneal thickness (CCT). The secondary aim was to prove tolerability and practicability of RT under "study conditions" and "routine practice conditions." METHODS: In group 1 (52 eyes/28 patients), all measurements were taken by the same physician, in the same room and order: non-contact optical pachymetry, RT, slit lamp inspection, GAT. Patients were questioned about discomfort or pain. In group 2 (49 eyes/27 patients), tonometry was performed by three other physicians during routine examinations. RESULTS: RT was well tolerated and safe. Intraocular pressure (IOP) ranged between 6 mm Hg and 48 mm Hg. No different trends were found between the groups. RT tended to give slightly higher readings: n = 101, mean difference 1.0 (SD 2.17) mm Hg; 84.1% of RT readings within plus or minus 3 mm Hg of GAT; 95% confidence interval in the Bland-Altman analysis -3.2 mm Hg to +5.2 mm Hg. Both RT and GAT showed a weak positive correlation with CCT (r2 0.028 and 0.025, respectively). CONCLUSIONS: RT can be considered a reliable alternative for clinical screening and in cases where positioning of the head at the slit lamp is impossible or topical preparations are to be avoided.

Ultrasound assessment of detrusor thickness in men-can it predict bladder outlet obstruction and replace pressure flow study?

PURPOSE: We estimated the diagnostic accuracy of ultrasound detrusor thickness measurement for BOO and investigated whether this method can replace PFS for the diagnosis of BOO in some patients with lower urinary tract symptoms. MATERIALS AND METHODS: Detrusor thickness was measured by linear ultrasound (7.5 MHz) at a filling volume of greater than 50% of cystometric capacity in 102 men undergoing PFS for LUTS. All patients with prior treatment for bladder outlet obstruction and those with underlying neurological disorders were excluded from analysis. Detrusor thickness was correlated with PFS data. Obstruction was defined according to the Abrams-Griffiths nomogram. RESULTS: Detrusor thickness was significantly higher (p <0.0001) in obstructed (61 cases, median detrusor thickness 2.7 mm, IQR 2.4 to 3.3) compared to unobstructed (18 cases, median detrusor thickness 1.7 mm, IQR 1.5 to 2) as well as equivocal (23 cases, median detrusor thickness 1.8 mm, IQR 1.5 to 2.2) cases. A weak to medium Spearman correlation was found between detrusor thickness and PFS parameters. For a diagnosis of BOO, detrusor thickness of 2.9 mm or greater had a positive predictive value of 100%, a negative predictive value of 54%, specificity of 100% and sensitivity of 43%. ROC analysis revealed that detrusor thickness had a high predictive value for BOO with an AUC of 0.88 (95% CI 0.81-0.94). CONCLUSIONS: In men with LUTS without prior treatment and/or neurological disorders, ultrasonographically assessed detrusor thickness 2.9 mm or greater has a high predictive value for BOO and can replace PFS for the diagnosis of BOO. However, this cutoff value needs to be validated in a larger study population.

Two- to 9-year clinical results of alumina ceramic-on-ceramic THA

From June 1997 to June 2003 we performed 194 total hip arthroplasties on 173 patients using alumina ceramic-on-ceramic bearings as part of a prospective United States Food and Drug Administration/Investigational Device Exemption study. The average patient age at surgery was 49.9 years. Minimum followup time was 2 years (mean 4.3 years, range 2-9 years). We evaluated survival rate, implant- and nonimplant-related complications. Clinical outcomes included the Merle d'Aubigné score. We assessed radiographs for signs of osteolysis, component loosening, and implant wear. No patients had osteolysis and there were no hip dislocations. Implant survivorship for all hips with aseptic revision of any component was 96% (CI, 91-100) at 9 year; survivorship for hips without prior surgery was 99.3%, (CI, 98-100). There was a 1.7% incidence of implant-related complications. Our data help confirm two United States FDA/IDE studies on alumina ceramic-on-ceramic total hip arthroplasty that reported low aseptic revision rates and low revision rates for instability. Total hip arthroplasty using alumina ceramic-on-ceramic implants is a safe and reliable procedure in the comparably young and active patient.