Comparative Assessment of Distribution Characteristics and Ocular Pharmacokinetics of Norvancomycin Between Continuous Topical Ocular Instillation and Hourly Administration of Eye Drop.

BACKGROUND: The aim of this study was to compare the distribution characteristics and ocular pharmacokinetics of norvancomycin (NVCM) in ocular tissues of the anterior segment between continuous topical ocular instillation and hourly administration of eye drop in rabbits. METHODS: Sixty rabbits were randomly divided into two groups: continuous topical ocular instillation drug delivery (CTOIDD) group and eye drop (control) group. In the CTOIDD group, NVCM solution (50 mg/mL) was perfused to the ocular surface using the CTOIDD system at 2 mL/h up to 10 h and the same solution was administered at one drop (50 µL) per hour for 10 h in the control group. Animals (N=6 per time-point per group) were humanely killed at 2, 4, 6, 10, and 24 h to analyze their ocular tissues and plasma. The concentrations of NVCM in the conjunctiva, cornea, aqueous humour, iris, ciliary body and plasma were measured by HPLC with photodiode array detector. The pharmacokinetic parameters were calculated by Kinetica 5.1. RESULTS: The highest concentrations of NVCM for the CTOIDD group and control group were 2105.45±919.89 µg/g and 97.18±43.14 µg/g in cornea, 3033.92±1061.95 µg/g and 806.99±563.02 µg/g in conjunctiva, 1570.19±402.87 µg/g and 46.93±23.46 µg/g in iris, 181.94±47.11 µg/g and 15.38±4.00 µg/g in ciliary body, 29.78±4.90 µg/mL and 3.20±1.48 µg/mL in aqueous humour, and 26.89±5.57 µg/mL and 1.90±1.87 µg/mL in plasma, respectively. The mean NVCM levels significantly increased at all time-points in cornea, iris, and ciliary body (p<0.05) in the CTOIDD group. The AUC0-24 values in the CTOIDD group were 27,543.70 µg·h/g in cornea, 32,514.48 µg·h/g in conjunctiva, 8631.05 µg·h/g in iris, 2194.36 µg·h/g in ciliary body and 343.9 µg·h/mL in aqueous humour, which were higher than for the eye drop group in all tissues. CONCLUSION: Since continuous instillation of NVCM with CTOIDD could reach significantly higher concentrations and was sustained for a longer period compared with hourly administration of eye drop, CTOIDD administered NVCM could be a possible method to treat bacterial keratitis.

Assessment of anti-diabetic activity of peanut shell polyphenol extracts.

The present study aimed to evaluate the anti-diabetic property of peanut shell polyphenol extracts (PSPEs). Diabetic rats were oral-administrated with PSPE at doses of 50, 100, and 200 mg/kg body weight (BW) per day for 28 consecutive days, with metformin (Met) as a positive control. The results showed that, similar to the Met treatment, administration of PSPE caused significant decreases in food intake, water intake, fasting blood glucose, total cholesterol, triglyceride, low-density lipoprotein cholesterol, and methane dicarboxylic aldehyde in serum, and significant increases in BW, insulin level, high-density lipoprotein cholesterol, superoxide dismutase, glutathione, and liver glycogen. Further, glucose tolerance was markedly improved in the PSPE-treated diabetic groups. Histopathological results showed that PSPE improved cellular structural and pathological changes in liver, kidney, and pancreatic islets. Collectively, the results indicated that the hypoglycemic effects of PSPE on high-fat diet/streptozotocin (HFD/STZ)-induced diabetes are comparable to Met, though their exact mechanism actions are still under investigation. Therefore, the current study suggests that PSPE could be a potential health-care food supplement in the management of diabetes.

Assessment of Sarcoplasmic Reticulum Calcium Reserve and Intracellular Diastolic Calcium Removal in Isolated Ventricular Cardiomyocytes.

Intracellular calcium recycling plays a critical role in regulation of systolic and diastolic function in cardiomyocytes. Cardiac sarcoplasmic reticulum (SR) serves as a Ca2+ reservoir for contraction, which reuptakes intracellular Ca2+ during relaxation. The SR Ca2+ reserve available for beats is determinate for cardiac contractibility, and the removal of intracellular Ca2+ is critical for cardiac diastolic function. Under some pathophysiological conditions, such as diabetes and heart failure, impaired calcium clearance and SR Ca2+ store in cardiomyocytes may be involved in the progress of cardiac dysfunction. Here, we describe a protocol to evaluate SRCa2+ reserve and diastolic Ca2+ removal. Briefly, a single cardiomyocyte was enzymatically isolated, and the intracellular Ca2+ fluorescence indicated by Fura-2 was recorded by a calcium imaging system. To employ caffeine for inducing total SR Ca2+ release, we preset an automatic perfusion switch program by interlinking the stimulation system and the perfusion system. Then, the mono-exponential curve fitting was used for analyzing decay time constants of calcium transients and caffeine-induced calcium pulses. Accordingly, the contribution of the SR Ca2+-ATPase (SERCA) and Na+-Ca2+ exchanger (NCX) to diastolic calcium removal was evaluated.

A Low-cost, Highly-stable Surface Enhanced Raman Scattering Substrate by Si Nanowire Arrays Decorated with Au Nanoparticles and Au Backplate.

We present a facile and cost-effective manner to fabricate a highly sensitive and stable surface enhanced Raman scattering (SERS) substrate. First, a silicon nanowire array (SiNWA) is tailored by metal-assisted chemical etching (MaCE) method as a scaffold of the desired SERS substrate. Next, with an oblique angle deposition (OAD) method, optimized gold nanoparticles (AuNPs) are successfully decorated on the surface of the SiNWA. These AuNPs enable a strong localized electric field, providing abundant hot spots to intensify the Raman signals from the targeting molecules. By applying a well-established methodology, Taguchi method, which is invented for designing experiments, the optimized combination of parameters is obtained efficiently. The experimental results are also confirmed by finite-difference time-domain (FDTD) simulation calculations. Besides, a gold metal backplate (AuMBP) is applied to further enhancing the Raman signal intensity. Based on this developed SERS substrate, we demonstrated an enhancement factor (EF) of 1.78 × 106 and a coefficient of variation (CV) of 4.2%. Both EF and CV indicate a highly stable property and the optimized SERS substrate substantially outperform the commercial product. In the end, we also demonstrate a quantitative measurement on practical application of detecting malachite green (MG) with concentration from 10 nM to 100 µM.

[A 10-year-review (1998 - 2007) on 3449 cases of osteoporotic hip fractures: trend of hospitalization and inpatient costs].

OBJECTIVE: The purpose of this retrospective research was to analyze the trend of hospitalized prevalence in the past 10 years (1998 - 2007) and to estimate resource utilization associated with osteoporotic hip fractures, including hospital length of stay and inpatient costs in Guangzhou, China. METHODS: 3449 patients aged 50 years and older, hospitalized for primary diagnose of hip fractures in both hospitals in the past ten years were included in our study. Completed data was obtained retrospectively from the hospital medical records. Clinical parameters such as sex-specifics, hospital length of stay, inpatient costs, and the constitutions of the inpatient costs were analyzed with multiple statistics methods and regressions. RESULTS: Over the 10-year study period, the number of hospitalizations for hip fractures increased with a curve model. Male and female ratio was 1:1.95 with an average age of the patients as 76.32 +/- 9.52 years old. Average hospital length of stay was 23.59 +/- 13.48 days with no significant difference between males and females, years of admission and the different diagnoses. The number of hospitalization went to the top at the age of 70 to 79 years old (38.45%), followed by 80-89 years old (33.08%). Femoral neck fractures was significantly more than that of inter-trochanteric fractures in those patients aged 50 to 79 years (P < 0.01) but less than those intertrochanteric fractures aged 90 years and older (P < 0.05). Average inpatient costs is about 23.52 +/- 17.00 thousand Yuan (RMB) (femoral neck fractures is about 25.09 +/- 17.62 thousand Yuan and intertrochanteric fracture is 21.44 +/- 15.92 thousand Yuan) of which treatment costs (included implants, materials used in the theatre and routinely care of the wound) contributed 52%, pharmacy intervention 25%, operation 6%, ward expenditure 5%, radiology and physical investigation 5%, and chemistry test 4%. The inpatient cost went to a peak at the age of 60 - 69 years old and were significantly correlated with the hospital length of stay. The cost increased every year in the past 10 years by 6.18%. CONCLUSION: These results emphasized that the growing economic impact arising from the inpatient treatment of osteoporotic hip fractures and most of which related to treatment cost (include implants, materials used in the theatre and routinely care of the wound), and drugs and always correlated to length of hospital stay. Cost control should be paid more attention to the implants and drugs.