Development of polyvinylpyrrolidone/paclitaxel self-assemblies for breast cancer

The goal of this investigation was to develop and demonstrate a polymer/paclitaxel self-assembly (PTX-SA) formulation. Polymer/PTX-SAs were screened based on smaller size of formulation using dynamic light scattering analysis. Additionally, fluorescence microscopy and flow cytometry studies exhibited that polyvinylpyrrolidone (PVP)-based PTX-SAs (PVP/PTX-SAs) had superior cellular internalization capability in MCF7 and MDA-MB-231 breast cancer cells. The optimized PVP/PTX-SAs exhibited less toxicity to human red blood cells indicating a suitable formulation for reducing systemic toxicity. The formation of PVP and PTX self-assemblies was confirmed using fluorescence quenching and transmission electron microscopy which indicated that the PVP/PTX-SAs were spherical in shape with an average size range of 53.81 nm as detected by transmission electron microscopy (TEM). FTIR spectral analysis demonstrates incorporation of polymer and paclitaxel functional groups in PVP/PTX-SAs. Both proliferation (MTS) and clonogenic (colony formation) assays were used to validate superior anticancer activity of PVP/PTX-SAs in breast cancer cells over paclitaxel. Such superior anticancer activity was also demonstrated by downregulation of the expression of pro-survival protein (Bcl-xL), upregulation of apoptosis-associated proteins (Bid, Bax, cleaved caspase 7, and cleaved PARP) and -tubulin stabilization. These results support the hypothesis that PVP/PTX-SAs improved paclitaxel delivery to cancer cells.

Foreign body in upper digestive tract.

OBJECTIVE: Foreign body ingestion is a common clinical problem, encountered in children. METHODS: A total number of 104 patients with ingested foreign body admitted in our hospital are reviewed. Endoscopic removal was done for all foreign objects impacted in esophagus. RESULT: In 84.6% cases, history of having swallowed the foreign body was most common symptom. Majority of patients (61.53%) presented within 24 hours after ingestion of foreign body. Coins were the most frequent offending agents in children (87.5%). Seventy six cases of coins were impacted in the postcricoid region. Complications of retropharyngeal abscess was seen in two cases (1.92%), which was associated with sharp foreign body. CONCLUSION: Early removal of these sharp foreign bodies must be considered to reduce the risk of this complication.

Choanal atresia: transnasal endoscopic technique.

OBJECTIVE: This article attempts to address the controversy between, endoscopic and traditional approaches to neonatal choanal atresia. METHOD: Congenital choanal atresia has been recognized for over 200 years, first described by Roedere in 1775. This condition is uncommon, occurring in approximately 1 in 7000 live births. Unfortunately a single ideal procedure for this condition does not exist. RESULTS: Stankiewicz is credited with the first description of endoscopic techniques for choanal atresia repair. All patients diagnosed to have choanal atresia, treated between 1999 and 2000 were reviewed. Out of four patients two underwent endoscopic repair. CONCLUSION: Transnasal endoscopic technique is followed by stenting with endotracheal portex tubes for 4-6 weeks in the initial surgical procedure of choice.

Tracheobronchial foreign bodies.

OBJECTIVE: [corrected] Foreign body inhalation is an extremely serious problem in children and sometimes result in sudden death. The current mortality rate from foreign body inhalation is between 0% and 1.8% according to various studies. In spite of this, undiagnosed and unsuspected foreign bodies still occur in the airway. METHODS: Pediatric patients with documented foreign body inhalation, treated in the Department of Pediatrics, Bapuji Hospital, JJM Medical College during 1997-2000 are included in the analysis. Children with or without positive history of aspiration were examined and the diagnosis was made on the basis of history, clinical findings, radilogic evaluation and strong index of suspicion in those children where reasonable appropriate treatment failed to resolve the respiratory symptoms. Bronchoscopy was performed for a suspected foreign body on 165 children. RESULT: A review of 165 pediatric cases of suspected foreign body aspiration revealed, children between 1 and 3 years were found to be very vulnerable for aspiration. Majority of children were boys. Over 70% of the patients had positive history of inhalation. Only 60% of the patients presented immediately, that is within 24 hours after aspiration. Common symptoms were cough and respiratory distress. Physical examination showed abnormal finding in 91% of cases. Decreased air entry was the significant clinical sign. Obstructive emphysema was found in majority of the cases (49.5%). Rigid bronchoscopy under general anaesthesia was the preferred method for removal of aspirated foreign body. In 65 (61.9%) cases foreign body was lodged in the right main bronchus and majority of these were organic in nature, that is 96 (91.43%). CONCLUSION: Tracheobronchial foreign bodies should be strongly suspected in pediatric age group who present with a suggestive history, even when physical and radiographic evidence is absent. The modalities of diagnosis, management and outcome are discussed.