Membrane fusion is a key event in many biological processes. The fusion process, both in vivo and in vitro, is induced by different agents which include mainly proteins and peptides. For protein- and peptide-mediated membrane fusion, conformational reorganization serves as a driving force. Small drug molecules do not share this advantage; hence, drug induced membrane fusion occurring in absence of any other fusogenic agent and at physiologically relevant concentration of the drugs is a very rare event. To date, only three drugs, namely, meloxicam (Mx), piroxicam (Px), and tenoxicam (Tx), belonging to the oxicam group of non steroidal anti-inflammatory drugs (NSAIDs), have been shown by us to induce fusion at very low drug to lipid ratio without the aid of any other fusogenic agent. In our continued effort to understand the interplay of different physical and chemical parameters of both the participating drugs and the membrane on the mechanism of this drug induced membrane fusion, we present here the effect of increase in orientational order of the lipid chains and increase in head group spacing. This is achieved by studying the effect of low concentration cholesterol (<10 mol %) at temperatures above the chain-melting transition. Low concentration cholesterol (<10 mol %), above the gel to fluid transition temperature, is mainly known to increase orientational order of the lipid chains and increase head group spacing. To isolate the effect of these parameters, small unilameller vesicles (SUVs) formed by dimyristoylphosphatidylcholine (DMPC) with an average diameter of 50-60 nm were used as simple model membranes. Fluorescence assays were used to probe the time dependence of lipid mixing, content mixing, and leakage and also used to determine the partitioning of the drugs in the membrane bilayer. Differential scanning calorimetry (DSC) was used to study the effect of drugs in the presence of cholesterol on the chain-melting temperature which reflects the fluidization effect of the hydrophobic tail region of the bilayer. Our results show contradictory effect of low concentration cholesterol on the fusion induced by the three drugs, which has been explained by parsing the effect of orientational order and increase in head group spacing on the fusion process.

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Introduction: There is a saying that “cancer cures smoking” as people often quit tobacco after diagnosis of cancer. Very few studies have analyzed the change in tobacco habits of a user after diagnosis of cancer in a relative or friend. Materials and Methods: In this cross-sectional study, 161 friends and relatives of 40 patients treated at Tata Memorial Hospital, Mumbai, India, were interviewed. They were given a questionnaire related to their tobacco habits. The results were analyzed statistically using Wilcoxon signed-rank test and Mann–Whitney test using SPSS. Results: Of the studied individuals, 114 were friends and 47 were blood relatives. 141 used smokeless tobacco, 18 were smokers, and 2 consumed tobacco in both the forms. The mean frequency of tobacco consumption among the friends and relatives before diagnosis of cancer was 12.24 per day and that at the time of interview was 9.76 per day. 35 persons (21.7%) stopped consumption whereas 19 (11.8%) reduced usage after diagnosis of cancer. The difference in mean consumption at median duration of 174 days is statistically significant ( P = 0.0005). Conclusions: The diagnosis of tobacco-related cancer has significant impact on the tobacco consumption of friends and relatives. The abstinence rate is comparable to that of various tobacco deaddiction therapies in vogue.

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A simple stability indicating RP-HPLC method was validated for determination of ipratropium bromide in the bulk drug. The drug was resolved using HPLC Column (Kromasil ODS 150 x 4.6 mm C18 column) with mobile phase of HPLC grade acetonitrile:potassium di-hydrogen phosphate buffer (60:40 V/V) at a flow rate of 1 ml/min. The retention time of ipratropium bromide was 3.7 min with UV detection at 254 nm. The method was validated with respect to linearity, sensitivity, accuracy, precision and robustness as per the International Conference on Harmonization (ICH) guidelines. The method was specific and it was observed that no interference with diluents. The linearity was established over the concentration range of 20-120 μg/ml with correlation coefficients (r2) 0.9958 for ipratropium bromide. The mean recovery was found to be in the range of 99.8% for ipratropium bromide. The % R.S.D. values for intraday precision study and inter-day study were <1.0%, confirming that the method was sufficiently precise. The drug was subjected to forced degradation under different conditions. The drug was degraded more in oxidative condition (28.89%) then alkaline condition (26.39%) then acidic condition (13.42%). There was no degradation seen under the thermal conditions.