Evaluation of Fluoride Release in Chitosan-Modified Glass Ionomer Cements

ObjectiveThis study assessed the influence of chitosan nanoparticles on the fluoride-releasing ability of 4 glass ionomer cement (GIC) through an in vitro analysis.MethodsFour types of GIC (type II light cure universal restorative, type II universal restorative, GC Fuji VII, and type IX) were modified with nanochitosan particles; 10% chitosan was added to the glass ionomer liquid. Six specimens for each of the 4 groups were created, using expendable Teflon moulds. Discs of each type of GIC (n = 6) were immersed in deionised water at various time intervals. Electrodes selective for fluoride ions were employed to analyse the amount of released fluoride at 1, 7, 14, 21, and 28 days.ResultsChitosan-modified GICs showed greater fluoride release than conventional GICs at all time points. All samples showed an initial high release of fluoride that tapered off with time. The total amount of fluoride released increased from the 1st day to the 28th day on adding chitosan to all the 4 types of GIC. Amongst those, type IX high-strength posterior extra with chitosan released a considerably higher quantity of fluoride at all time intervals.ConclusionsIn all the experimental groups, adding chitosan to the glass ionomer liquid had an accelerating effect on its fluoride-releasing property.     

Rationalization of physicochemical characters of oxazolyl thiosemicarbazone analogs towards multi-drug resistant tuberculosis: a QSAR approach

The emergence of multi-drug resistant (MDR) strains of Mycobacterium tuberculosis and the continuing pandemic of tuberculosis emphasizes the urgent need for the development of new and potent anti-tubercular agents. In an effort to develop new and more effective agents to treat tuberculosis emphasis was focused on quantification of structure-activity relationship of oxazolyl thiosemicarbazone derivatives. The de novo analysis gave insight to some important structural features i.e. nitro group on phenyl ring at R(1) position is optimal for the activity and might be responsible for electronic interaction, while phenyl ring at R position interact with the hydrophobic pocket more effectively as compared to unsubstituted or methyl substituted analogs. Hansch approach offered the understanding and parameterization of interactions of the inhibitor with receptor. Similarly QSAR analysis gave some important physicochemical properties, i.e. empirical aromatic index (ARR) and 3D-MoRSE code value of scattering angle at 8A(-1). These two physicochemical properties shall be helpful in the development of more potent analogs.     

Non-contact mapping in the treatment of ventricular tachycardia after myocardial infarction

The treatment of ventricular tachycardia (VT) in patients with underlying ischaemic heart disease (IHD) remains a challenge. Ablation of these arrhythmias may have a significant impact on quality of life for patients. For those patients with haemodynamically unstable VT, ablation success rates have been improved by the use of non-contact mapping. Care has to be taken in the analysis and interpretation of non-contact mapping studies, as chamber size and filter settings have a large effect on the appearance of the activation maps produced. Despite this limitation the majority of VT exit sites and part of the diastolic pathway can be identified with non-contact mapping techniques.     

Percutaneous epicardial ablation reverses ventricular tachycardia mediated cardiomyopathy

We report on the case of an 18-year-old girl with asymptomatic incessant ventricular tachycardia. Initial attempts at endocardial ablation failed and she was monitored until her cardiac function deteriorated. A percutaneous epicardial approach with electroanatomical mapping was then used which successfully terminated the tachycardia. Left ventricular size and function subsequently returned to normal. This case demonstrates that percutaneous epicardial ablation of ventricular tachycardia is safe and feasible in young patients and highlights the importance of recognising this at an early stage.     

Rationalization of physicochemical characters of 1,5-diarylpyrazole analogs as dual (COX-2/LOX-5) inhibitors: a QSAR approach

Arachidonic acid metabolizing enzymes cyclooxygenases and lipoxygenases lead to the formation of various eicosanoids involved in variety of human diseases, like inflammation, fever, pain, rheumatic and osteoarthritis, etc. Non-steroidal anti-inflammatory drugs are useful tools in the treatment of prostaglandin mediated complications. The development of dual inhibitors may prevent a drift of arachidonic acid metabolism towards the other pathway, leading to potential side effects. Hence emphasis was focused on quantification of structure-activity relationship, with a view to delineating the influence of key COX-2/LOX-5 activity, to explore structural insights to aid the designing of safer dual inhibitors. The quantification of the structural features of 1,5-diarylpyrazole analogs with various biological activities gave some important structural insights, i.e. Hy (hydrophilic factor) and Mor17v (3D molecular representation of structure based on electron diffraction code). These two physicochemical properties may be helpful in development of more selective dual COX-2/LOX-5 inhibitors.     

Phase I/II study of docetaxel, ifosfamide, and doxorubicin in advanced, recurrent, or metastatic soft tissue sarcoma (STS)

Summary Background: Based on reports of the efficacy of docetaxel (T) in STS, we undertook a phase I/II trial to determine the response rate (RR), dose-limiting toxicity (DLT), and maximum tolerated dose (MTD) of addition of T to doxorubicin (A) and ifosfamide (I) in advanced STS. Methods: Patients with advanced, recurrent, or metastatic STS, without prior chemotherapy, were enrolled in a dose escalation trial. Dose levels: I-A 40 mg/m²; I 4.0 gm/m²; T 40 mg/m², II-A 50; I 5.0; T 50, III-A 60; I 6.0; T 60, and IV-A 75; I 7.5; T 75. MTD was defined as the dose producing DLTs in ≥2 of 3–6 patients treated. Results: 21 patients were accrued. Median age: 55 (28–78) years. Histology: leiomyosarcoma 10, spindle cell sarcoma 3, synovial sarcoma 2, angiosarcoma 1, fibrous histiocytoma 1, epitheliod hemangio-endothelioma 1, and 3 not specified. MTD was level III (A 60, I 6.0, and T 60). DLT was myelosuppression. All grade 4 toxicities were hematologic. Patients received median 2 cycles (range 2–9). Eight patients (38%) achieved partial response (PR). PR occurred after six cycles in 5 patients. 18 patients died. Median overall survival: 17 months (95% CI, 9.1–33.6 months). Conclusions: The recommended Phase II dose of this combination is level III: A 60 mg/m², I 6.0 g/m², T 60 mg/m², with mesna and granulocyte-colony stimulating factor. The RR is similar to that of AI in other trials, but the survival is better than anticipated.     

Thrombocytosis as a prognostic factor for survival in patients with metastatic renal cell carcinoma

BACKGROUND: It has been suggested that thrombocytosis, as defined by a platelet count >400,000/microL, is a negative predictor for survival among patients with metastatic renal cell carcinoma. However, this has not been a uniform finding. METHODS: To address this issue, retrospective analysis of 700 previously untreated patients entering on institution review board-approved phase 1, 2, or 3 clinical trials in the United States and Europe was conducted between 1982 and 2002. RESULTS: Thrombocytosis was present at study entry in 25% of patients. Median baseline platelet count was 304,000/microL (range, 86-1,420,000/microL). Eighty-seven percent of patients died with a median survival of 13.0 months. Median follow-up for patients not known to have died was 2.4 years. On univariate analysis, patients with elevated platelet counts had significantly shorter survival than patients with normal platelet counts; median survivals of 8.4 and 14.6 months, respectively, P < .001. However, platelet count was associated with several clinical and biochemical factors, including gender, age, performance status, time from diagnosis to study entry, prior radiotherapy or nephrectomy, presence of liver metastasis, number of metastatic sites, amount of hemoglobin, white blood cell count, amount of lactate dehydrogenase, and amount of serum alkaline phosphatase. Several of these factors have previously been reported as prognostic indicators for survival, and, therefore, multivariable analyses were conducted to determine whether thrombocytosis is an independent predictor of survival. After adjusting for multiple factors, thrombocytosis continued to impact negatively on survival, P < .001. CONCLUSIONS: Thrombocytosis was found to be an independent prognostic factor for survival in patients with metastatic renal cell carcinoma.