Polarization properties of retinal blood vessel walls measured with polarization sensitive optical coherence tomography

A new method based on polarization-sensitive optical coherence tomography (PS-OCT) is introduced to determine the polarization properties of human retinal vessel walls, in vivo. Measurements were obtained near the optic nerve head of three healthy human subjects. The double pass phase retardation per unit depth (DPPR/UD), which is proportional to the birefringence, is higher in artery walls, presumably because of the presence of muscle tissue. Measurements in surrounding retinal nerve fiber layer tissue yielded lower DPPR/UD values, suggesting that the retinal vessel wall tissue near the optic nerve is not covered by retinal nerve fiber layer tissue (0.43°/µm vs. 0.77°/µm, respectively). Measurements were obtained from multiple artery-vein pairs, to quantify the different polarization properties. Measurements were taken along a section of the vessel wall, with changes in DPPR/UD up to 15%, while the vessel wall thickness remained relatively constant. A stationary scan pattern was applied to determine the influence of involuntary eye motion on the measurement, which was significant. Measurements were also analyzed by two examiners, with high inter-observer agreement. The measurement repeatability was determined with measurements that were acquired during multiple visits. An improvement in accuracy can be achieved with an ultra-broad-bandwidth PS-OCT system since it will provide more data points in-depth, which reduces the influence of discretization and helps to facilitate better fitting of the birefringence data.     

Curcumin reduces indomethacin-induced damage in the rat small intestine

Non-steroidal anti-inflammatory drugs (NSAIDs) are commonly used in clinical medicine. Their utility is, however, often limited by the adverse effects they produce in the gastrointestinal tract. Oxidative stress has been shown to occur in the small intestine in response to the oral administration of indomethacin, an NSAID commonly used in toxicity studies. In view of this, the effect of curcumin, an agent with anti-oxidant properties, was evaluated on indomethacin-induced small intestinal damage in a rat model. Rats were pretreated with various doses of curcumin (20 mg kg(-1), 40 mg kg(-1) and 80 mg kg(-1)) before administering indomethacin at 20 mg kg(-1). Various parameters of oxidative stress and the extent of small intestinal damage produced by indomethacin, with and without pretreatment with curcumin, were measured. Macroscopic ulceration was found to occur in the small intestine in response to indomethacin. The viability of enterocytes from indomethacin-treated animals was significantly lower than those from control animals. Drug-induced oxidative stress was also evident as seen by increases in the levels of malondialdehyde and protein carbonyl and in activities of pro-oxidant enzymes such as myeloperoxidase and xanthine oxidase in indomethacin-treated rats. Concomitant decreases were seen in the activities of the antioxidant enzymes catalase and glutathione peroxidase in these animals. Pretreatment with curcumin was found to ameliorate these drug-induced changes. Thus, curcumin appears to hold promise as an agent that can potentially reduce NSAID-induced small intestinal damage.     

High prevalence of low vitamin D and musculoskeletal complaints in women with breast cancer

Reduced vitamin D levels may play a significant role in the development of fractures and musculoskeletal pains reported in patients on aromatase inhibitors (AIs) for breast cancer. In this study, we evaluated the vitamin D status in postmenopausal women with non-metastatic breast cancer who were about to start AI therapy. This study was conducted on community dwelling postmenopausal subjects, aged 35-80 years, with early non-metastatic breast cancer (up to stage IIIA), who were about to start therapy using third generation AIs. Symptoms of joint and muscle pains were obtained using a modified Leuven menopausal questionnaire. 25-hydroxyvitamin D [25(OH)D] was evaluated by radioimmunoassay while bone mineral density (BMD) of the lumbar spine and the proximal femur by dual energy x-ray absorptiometry (DXA). Of the 145 participants (mean age = 60.96 ± 0.88 years), 63 of 145 (43.5%) had baseline levels of 25(OH)D of < 20 ng/mL (deficient), 50 of 145 (34.5%) had levels between 20 and 29 ng/mL (insufficient), and only 32 of 145 (22%) had ≥ 30 ng/mL (sufficient); thus, 113 of 145 (78%) had low 25(OH)D levels (i.e., < 30 ng/mL). Arthralgias and myalgias were found in 61.3% and 43% of patients, respectively; and of those, 83.3% and 88.1% had 25(OH)D of < 30 ng/mL, respectively. Prevalence of vitamin D deficiency is high in breast cancer women and this may increase the risk of bone loss and fractures in those who are going to start AIs. Moreover, musculoskeletal pains are common in breast cancer women, even before the initiation of AIs and in association with low vitamin D in the majority. Future studies may be needed to establish the contribution of low vitamin D, if any, on the prevalence of musculoskeletal pains in women on AIs.     

Impact of Local Resources on Hospitalization Patterns of Medicare Beneficiaries and Propensity to Travel Outside Local Markets

Purpose: To examine how local health care resources impact travel patterns of patients age 65 and older across the rural urban continuum.
Methods: Information on inpatient hospital discharges was drawn from complete 2004 hospital discharge files from the Healthcare Cost and Utilization Project (HCUP) State Inpatient Databases (SID) for New York, California, and Florida, and the 2003 hospital discharge file for Pennsylvania. The study population was Medicare patients with admissions for ambulatory care sensitive conditions. Analysis was at the patient-level, and area contextual variables were developed at the Primary Care Service Area (PCSA) level. Local resources considered included inpatient supply, provider supply, supply of international medical graduates, and critical access hospitals (CAHs) in the patient's PCSA.
Findings: Findings generally confirmed enhanced retention of the elderly in local markets with greater availability of community resources, although we observed considerable heterogeneity across states. Community resource variables such as median household income or inpatient hospital capacity were stronger and more consistent predictors along the urban rural continuum than any of the provider or CAH variables. Only in California and New York did we see significant effects for provider supply or CAH, but they were robust across the 2 states and models of travel propensity, always reducing the travel propensity.
Conclusions: Findings support policies aimed at augmenting supplies of critical access hospitals in rural communities, and increasing primary care physicians and hospital resources in both rural and urban communities.     

Evaluation of skeletal muscle relaxant activity of aqueous extract of Nerium oleander flowers in Albino rats

Objectives:

Nerium oleander is traditionally used in various diseases because of its medicinal properties. One of its uses is in musculoskeletal disorder. The aim of the study was to evaluate the skeletal muscle relaxant activity of the aqueous extract of Nerium oleander flowers (AENOF) in albino rats in comparison with diazepam.

Materials and Methods:

A total of 20 Swiss albino rats aged 6–7 weeks, of either sex, weighing about 100–150 g, were taken, and after acute toxicity studies two different doses were selected. The animals were divided into four different groups. The first group was kept as the control (normal saline), second as the standard (diazepam) and the remaining two groups as Test I and Test II, and given different doses of the AENOF. Skeletal muscle relaxant activity (motor coordination) on Rotarod and locomotor activity on photoactometer was performed. Statistical analysis was carried out by using analysis of variance, followed by Dunnett''s multiple comparison tests.

Results:

The result from the Actophotometer test and Rotarod test showed that the extract of AENOF significantly reduced (P < 0.05) the motor coordination of the tested animals.

Conclusions:

Our data indicates that AENOF possesses skeletal muscle relaxant activities.KEY WORDS: Actophotometer, muscle relaxant, Nerium oleander, rotarod, soxhlet apparatus     

Changes in preventable hospitalization patterns among the adults: a small area analysis of US states

The study examines the variation and changes in preventable hospitalization (PH) rates across small areas over 1995-2005 in 5 US states for adults (aged 18-64 years). Using hospital discharge data from the Agency for Healthcare Research and Quality and contextual data from Health Resources and Services Administration, the study examines the role of managed care, primary care physician supply, and sociodemographic factors on adult PH rates. A stronger influence of minority and uninsured status, weaker contributions of managed care enrollment in the commercial as well as in the Medicaid markets, and weaker contributions of primary care density may have caused slower than expected reduction in adult PH rates.     

Precision Attachment: Retained Overdenture

Precision attachments are small interlocking devices to connect prosthesis and abutments that offer a variety of solutions to the challenge of balance between functional stability and cosmetic appeal. Precision attachments have wide applications, used in fixed removable bridge, removable partial dentures, overdentures, implant retained overdentures, and maxillofacial prosthesis. Attachment retained overdentures helps in distribution of masticatory forces, minimizes trauma to abutments and soft tissues, attenuate ridge resorption, improves the esthetics and retains proprioception. The following case report discusses the use of resilient stud attachments to retain maxillary and mandibular overlay complete dentures.     

A Heuristic Approach to Automated Nipple Detection in Digital Mammograms

In this paper, a heuristic approach to automated nipple detection in digital mammograms is presented. A multithresholding algorithm is first applied to segment the mammogram and separate the breast region from the background region. Next, the problem is considered separately for craniocaudal (CC) and mediolateral-oblique (MLO) views. In the simplified algorithm, a search is performed on the segmented image along a band around the centroid and in a direction perpendicular to the pectoral muscle edge in the MLO view image. The direction defaults to the horizontal (perpendicular to the thoracic wall) in case of CC view images. The farthest pixel from the base found in this direction can be approximated as the nipple point. Further, an improved version of the simplified algorithm is proposed which can be considered as a subclass of the Branch and Bound algorithms. The mean Euclidean distance between the ground truth and calculated nipple position for 500 mammograms from the Digital Database for Screening Mammography (DDSM) database was found to be 11.03 mm and the average total time taken by the algorithm was 0.79 s. Results of the proposed algorithm demonstrate that even simple heuristics can achieve the desired result in nipple detection thus reducing the time and computational complexity.     

Anti-nidatory effect of a single, early post-ovulatory administration of mifepristone (RU 486) in the rhesus monkey

The hypothesis that post-coital administration of mifepristone(RU 486) as a single dose in the early luteal phase can be aneffective anti-nidatory strategy was tested using the rhesusmonkey as the experimental model. Incidence of pregnancy, vaginalbleeding patterns, profiles of menstrual cyclicity and of serumlevels of progesterone and oestrogen were examined followingadministration of RU 486 as a single dose of 10 mg/kg and 2mg/kg body weight on the second day after ovulation. In controlmonkeys (group 1; n = 5) receiving the vehicle alone (benzylbenzoate: olive oil, 1: 4, v/v) there was a 60% pregnancy rate.Following s.c. administration of RU 486 at both doses, no pregnancywas recorded in a total of 33 treatment cycles in 12 monkeys.Five monkeys received RU 486 at 10 mg/kg s.c. (group 2) in threeconsecutive cycles. All animals had complete inhibition of implantation;in addition, the treatment cycle length was prolonged (P <0.001) due to an extension of the luteal phase. The subsequentfollicular phase was unaffected. Mild, premature vaginal bleedingduring the luteal phase was recorded in five treatment cycles,3–5 days after drug application. Though the serum profilesof progesterone and oestrogen in these monkeys showed markedindividual variations, there was a characteristic progesteronerebound about 18–20 days after drug administration. Monkeysin group 3 were given RU 486 at 2 mg/kg, s.c. either for threeconsecutive cycles (group 3a; n = 4) or for two consecutivecycles (group 3b; n = 3). Premature luteal phase vaginal bleedingoccurred only in four treatment cycles, within 2–6 dayspost-treatment. An increase in both the duration (P < 0.001)and degree (P < 0.001) of menstrual flow as compared withthe pre-treatment cycles was recorded in six treatment cyclesof three monkeys in group 3. These animals did not have prematureluteal phase vaginal bleeding. Collectively, 100% protectionagainst pregnancy with no change in the cycle length was obtainedin all seven monkeys in 18 treatment cycles. Analysis of pooleddata revealed that the subsequent follicular phase, as wellas the ovarian steroid hormone profiles of treatment cycleswere unaffected. Thus, a single application of RU 486 in theearly secretory phase appears to be a potential anti-implantationstrategy for intercepting pregnancy in the primate.