ABSTRACT
The study aimed at investigating an inclusion complexation technique to improve solubility and dissolution characteristics of carvedilol by successful complexation with β-cyclodextrin. Inclusion complexes (ICs) of drug and β-cyclodextrin were prepared by kneading method in four different ratios. Physical mixtures were also prepared in identical ratios to compare the efficacy of prepared ICs. The preparations were subjected to rheological studies, drug loading, in vitro release study, FT-IR spectroscopy, thermal events analysis by DSC, X-ray diffraction, scanning electron microscopy (SEM) and accelerated stability study. IC granules were free flowing and compressible. FT-IR study denoted to absence of any chemical interactions between drug and carrier. DSC and X-ray diffraction suggested the presence of crystalline drug in the complexes. Dissolution of ICs revealed significant enhancement of release rate and extent compared to untreated drug. MDT, %DE and T25%, T50% and T80% indicated marked improvement in release rate from complexes. Kinetic modeling suggested that fickian diffusion was the predominant mechanism of drug release from solid complexes. Stability samples showed no significant alterations in DSC and FT-IR studies that referred to the stability of ICs. ICs were compatible, effective and stable over time. Further studies can be planned to investigate their therapeutic efficacy.
ABSTRACT
Aims: We sought to investigate norovirus burden in patients with complications of acute gastroenteritis in community level in Bangladesh. Thus, the aim of this study was to detect the incidence of norovirus in stool samples collected from study subjects with acute gastroenteritis who attended voluntarily in different community clinics at Savar area, Dhaka, Bangladesh. Methodology: The study enrolled patients from different community clinics in Savar area during July 2012 to December 2012. Stool specimens were collected in supplied stool container from patients as part of their diagnostic procedure. Viral RNA was extracted from the samples using the QIAamp® viral RNA mini kit (Qiagen, Germany). Real-time RT-PCR assay was conducted to identify different norovirus genogroups in the stool samples. Results: We detected norovirus exclusively in 23.8% (10/42) of the stool samples where rotavirus was absent. Over 80% patients were aged less than 2 years and all 10 norovirus-positive samples were detected within this age range (P = 0.17). Detection rates for norovirus was the highest in July and the lowest in November among the months covered in the study. Genogroup analysis of detected noroviruses showed 1(10%) as GI, 8 (80%) as GII and the remaining 1 (10%) as the mixture of GI and GII genogroups. Conclusions: This study has provided baseline incidence of norovirus diarrhea in patients attended at community hospitals in Savar area, Dhaka, Bangladesh. The infections were exclusively in children aged less than two years. Norovirus genogroup-II was predominant in the community infections covered under this study.