Adsorption of Salmon Calcitonin to PLGA Microspheres

Purpose. The interaction of salmon calcitonin (sCT) and poly (d,l-lactide-co-glycolide) was detected during preparation and evaluation of microspheres. The purpose of this study was to quantitate the extent and nature of the interaction. Methods. Blank microspheres were prepared by an aqueous emulsification solvent extraction technique. Adsorption studies were carried out at six concentrations of sCT and three concentrations of microspheres. Adsorption isotherms were constructed using the Langmuir and Freundlich treatments. Results. Adsorption at 1 mg/ml sCT concentration resulted in almost complete depletion of the peptide from the adsorption medium with the time to reach maximum adsorption decreasing with increasing microsphere concentration. At sCT concentrations below 100 µg/ml, a true equilibrium occurred in 1 hour or less while at higher concentrations (up to 350 µg/ml), a transient equilibrium was reached in 1 to 2 hours, followed by further adsorption of the peptide. The adsorption followed the Langmuir isotherm at concentrations below 200 µg/ml, indicating formation of a monolayer. Multilayer interaction, described by the Freundlich isotherm, occurred at higher concentrations and resulted in complete depletion of sCT from the adsorption medium. The affinity constant during monolayer formation was 0.09 and the plateau surface concentration was 5.1 µg/mg. The multilayer peptide-peptide adsorption showed a lower affinity (0.025) but higher capacity (24 µg/mg) than the monolayer peptide-polymer adsorption. Conclusions. The results show that poly (d,l-lactide-co-glycolide) microspheres have a high adsorption capacity for sCT which must be considered in formulating a controlled delivery product of this peptide.     

The role of ostiomeatal complex obstruction in maxillary fungus ball.

OBJECTIVE: The aim of this study was to clarify the role of ostiomeatal complex obstruction in maxillary fungus ball. STUDY DESIGN AND SETTING: Comparative study in a hospital setting of the mean Lund-Mackay scores for the anterior ethmoid and frontal sinuses of 54 versus 48 patients with maxillary fungus ball versus chronic unilateral rhinosinusitis, respectively. RESULTS: In cases with partial opacification in the maxillary sinus, the anterior ethmoid and frontal sinuses were diseased in the chronic unilateral rhinosinusitis group but not in the maxillary fungus ball group. In cases with total opacification in the maxillary sinuses, all anterior ethmoid and frontal sinuses in both groups were diseased, but the disease condition of the frontal sinuses was significantly less severe in the maxillary fungus ball group (P < 0.001). CONCLUSION AND SIGNIFICANCE: In this era of evidence-based medicine, we provide statistical data supporting the principle that maxillary fungus ball is not associated with osteomeatal complex obstruction and that another as-yet-unexplained mechanism must be responsible. EBM rating: B-3b.     

Prevalence of depressive and anxiety disorders in an assisted reproductive technique clinic

Hum. Reprod., 19, 2313–2318, 2004 The following mistake     

L-ascorbic acid produces hypoglycaemia and hyperinsulinaemia in anaesthetized rats

L-Ascorbic acid (Vitamin C) produced a marked reduction in the blood glucose concentration following intravenous injection (20-100 mg kg-1) to anaesthetized rats. This hypoglycaemic effect was accompanied by an increase in plasma insulin concentration. D-ascorbic acid produced a similar hypoglycaemic effect.     

Diagnostic value of GDx polarimetry in a Taiwan Chinese population.

PURPOSE: To study the diagnostic ability of scanning laser polarimetry with variable corneal compensation (GDx VCC) for early glaucomatous (EG) eyes and glaucoma-suspect (GS) eyes in a Taiwan Chinese population. METHODS: This prospective cross-sectional study included 82 EG eyes (mean deviation, MD: -3.32 +/- 2.20 dB), 45 GS eyes (MD: -2.43 +/- 2.16 dB), and 62 normal eyes. Retinal nerve fiber layer thickness of each subject was measured using GDx VCC and Humphrey Field Analyzer visual field testing. Measured GDx VCC parameters were compared among groups. The area under the receiver operating characteristic (AROC) curve of each parameter was used to differentiate normal from EG eyes or GS eyes. The correlation between MD and each parameter was also evaluated. RESULTS: For both normal versus EG and normal versus GS, the largest AROC values were for nerve fiber indicator, superior average thickness, and inferior average thickness. There was no significant correlation between MD and GDx-VCC-measured parameters either in EG or GS eyes. CONCLUSIONS: GDx VCC shows only moderate ability to distinguish normal eyes from eyes with early glaucoma. However, its diagnostic role in eyes with suspicious discs and normal visual fields is uncertain at this moment in the Taiwan Chinese population. Further studies are needed to address this issue.