Search

AbstractTraditional eye drops used for topically administering drugs have poor ocular bioavailability due to the biological barriers of the eye. There is an interest to design and develop novel drug delivery systems that would extend the precorneal residence time, reduce the frequency of administration and decrease dose-related toxicity. This study aimed to prepare Nanoparticles of Gemifloxacin Mesylate and incorporate them into an in situ gel. The nanoparticles were prepared by ionic gelation technique, using 32 factorial design. Sodium tripolyphosphate (STPP) was used to crosslink Chitosan. The optimized formulation of the nanoparticles (GF4) contained 0.15% Gemifloxacin Mesylate, 0.15% Chitosan and 0.20% STPP, producing 71 nm particle size and 81.11% entrapment efficiency. The prepared nanoparticles showed biphasic release, with an initial burst release of 15% in 1.0 hr and a cumulative drug release of 90.53% at the end of 24 hrs. After that, the prepared nanoparticles were incorporated into an in situ gel, using Poloxamer 407, producing a sustained drug release with efficient antimicrobial activity against gram-positive and gram-negative bacteria as confirmed by the cup plate method.

Traditional eye drops used for topically administering drugs have poor ocular bioavailability due to the biological barriers of the eye. There is an interest to design and develop novel drug delivery systems that would extend the precorneal residence time, reduce the frequency of administration and decrease dose-related toxicity. This study aimed to prepare Nanoparticles of Gemifloxacin Mesylate and incorporate them into an in situ gel. The nanoparticles were prepared by ionic gelation technique, using 32 factorial design. Sodium tripolyphosphate (STPP) was used to crosslink Chitosan. The optimized formulation of the nanoparticles (GF4) contained 0.15% Gemifloxacin Mesylate, 0.15% Chitosan and 0.20% STPP, producing 71 nm particle size and 81.11% entrapment efficiency. The prepared nanoparticles showed biphasic release, with an initial burst release of 15% in 1.0 hr and a cumulative drug release of 90.53% at the end of 24 hrs. After that, the prepared nanoparticles were incorporated into an in situ gel, using Poloxamer 407, producing a sustained drug release with efficient antimicrobial activity against gram-positive and gram-negative bacteria as confirmed by the cup plate method. [ABSTRACT FROM AUTHOR]

Aims: The process of differential diagnosis between epithelioid mesothelioma and lung adenocarcinoma has been progressing; however, there are no absolute immunohistochemical markers with which to definitively diagnose epithelioid mesothelioma. The aim of this study was to search for a novel negative marker of epithelioid mesothelioma. Methods and results: We immunohistochemically studied the applicability of mucin 21 (MUC21), which was identified in our previous study, as a novel, negative diagnostic marker for epithelioid mesothelioma. Seventy epithelioid mesotheliomas and 70 lung adenocarcinomas were investigated for the expression of MUC21, along with other previously reported markers, by the use of immunohistochemistry. MUC21 was expressed in only two of the 70 (3%) epithelioid mesotheliomas, as compared with 67 of the 70 (96%) lung adenocarcinomas. The sensitivity, specificity and accuracy of negative MUC21 expression for differentiating epithelioid mesothelioma from lung adenocarcinoma were 97%, 96%, and 96%, respectively; these are similar to those of carcinoembryonic antigen and claudin‐4, and better than those of thyroid transcription factor‐1, napsin‐A, and mucin 4. Conclusion: MUC21 could be used as an additional, novel, negative immunohistochemical marker to differentiate mesothelioma from lung adenocarcinoma. [ABSTRACT FROM AUTHOR]

Astroblastoma is a rare, enigmatic tumor of the central nervous system (CNS) which shares some clinicopathologic aspects with other CNS tumors, especially ependymoma. To further clarify the nature of astroblastoma, we performed clinicopathologic and molecular genetic studies on eight cases of astroblastoma. The median age of the patients was 14.5 years, ranging from 5 to 60 years, and seven of the patients were female. All tumors arose in the cerebral hemisphere and radiologically appeared to be well‐bordered, nodular tumors often associated with cystic areas and contrast‐enhancement. Six of the seven patients with prognosis data survived without recurrences during the follow‐up periods ranging from six to 76 months. One patient had multiple recurrences and died six years later. All tumors exhibited salient microscopic features, such as being well demarcated from the surrounding brain tissue, perivascular arrangement of epithelioid tumor cells (represented by "astroblastic" pseudorosettes, trabecular alignment, and pseudopapillary patterns), and hyalinized blood vessels. Immunoreactivity for GFAP, S‐100 protein, Olig2, and EMA was variably demonstrated in all tumors, and IDH1 R132H and L1CAM were negative. Array comparative genomic hybridization revealed numerous heterozygous deletions on chromosome X in the four tumors studied, and break‐apart fluorescence in situ hybridization demonstrated rearrangement of MN1 in five tumors with successful testing. The characteristic clinicopathologic and genetic findings support the idea that astroblastoma is distinct from other CNS tumors, in particular, ependymoma. In addition, MN1 rearrangement and aberrations of chromosome X may partly be involved in the pathogenesis of astroblastoma. [ABSTRACT FROM AUTHOR]

Encapsulation of a multimeric alcohol oxidase (AOx) in giant vesicles (GVs) was prepared by rapid evaporation method. The specific activity (477 U/mg-protein) of the GV encapsulated AOx was 3.5 fold higher than the free AOx. The half-life (˜59.4 hours) of the encapsulated AOx was 20-fold higher than the free enzyme at 30°C. Further, the GV was used to encapsulate AOx and HRP together as coupled reaction catalyst for chromogen-based optical detection of alcohols. The results confirmed potential application of the GV as micro-dimensional container for enhancing stability, activity and biosensing applications of AOx. [ABSTRACT FROM AUTHOR]