Macrocyclic complexes: synthesis, characterization, antitumor and DNA binding studies.

The present paper deals with the synthesis of novel macrocyclic complexes of the type [MLX]X, where [(M = Co(II) (1), and Ni(II) (2) X = (Cl2)]. The complexes are synthesized by the reaction of ligand(L)diquinolineno[1,3,7,9]tetraazacyclododecine-7,15-ethane(14H,16H)-benzene with the corresponding metal salts. The synthesized complexes are thoroughly characterized by elemental analysis, FT-IR, 1H-NMR, Mass and electronic spectra. The complexes (1) and (2) were evaluated for in vitro cytotoxicity against human breast adenocarcinoma cell (MCF-7). MTT cytotoxicity studies shows both the complexes are most effective. The binding properties of these complexes with calf thymus-DNA were studied by absorption, emission spectra, viscosity measurements, and thermal denaturation studies. On binding to CT-DNA, the absorption spectrum undergoes bathochromic and hypochromic shifts. The absorption spectral results indicate that the intrinsic binding constant (Kb) are 4.8 × 105 M-1 for (1) and 3.9 × 105 M-1 for (2) respectively, suggesting that complex (1) binds more strongly to CT-DNA than complex (2). The viscosity measurement results revealed the viscosity of sonicated rod like DNA fragments increased when the complex was added to the solution of CT-DNA. The synthesized ligand and its metal complexes are screened for antibacterial and antifungal activities.

Optimizing oxygenation and intubation conditions during awake fibre-optic intubation using a high-flow nasal oxygen-delivery system.

BACKGROUND: Awake fibre-optic intubation is a widely practised technique for anticipated difficult airway management. Despite the administration of supplemental oxygen during the procedure, patients are still at risk of hypoxia because of the effects of sedation, local anaesthesia, procedural complications, and the presence of co-morbidities. Traditionally used oxygen-delivery devices are low flow, and most do not have a sufficient reservoir or allow adequate fresh gas flow to meet the patient's peak inspiratory flow rate, nor provide an adequate fractional inspired oxygen concentration to prevent desaturation should complications arise. METHODS: A prospective observational study was conducted using a high-flow humidified transnasal oxygen-delivery system during awake fibre-optic intubation in 50 patients with anticipated difficult airways. RESULTS: There were no episodes of desaturation or hypercapnia using the high-flow system, and in all patients the oxygen saturation improved above baseline values, despite one instance of apnoea resulting from over-sedation. All patients reported a comfortable experience using the device. CONCLUSIONS: The high-flow nasal oxygen-delivery system improves oxygenation saturation, decreases the risk of desaturation during the procedure, and potentially, optimizes conditions for awake fibre-optic intubation. The soft nasal cannulae uniquely allow continuous oxygenation and simultaneous passage of the fibrescope and tracheal tube. The safety of the procedure may be increased, because any obstruction, hypoventilation, or periods of apnoea that may arise may be tolerated for longer, allowing more time to achieve ventilation in an optimally oxygenated patient.

Prevalence and factor associated with current smoking among medical students in coastal South India.

BACKGROUND: Smoking among health care personnel such as medical students is an important public health issue. More effective measures to reduce tobacco smoking among medical students are needed worldwide. Very few studies had been conducted in past in India and other developing countries to understand the magnitude of problem. OBJECTIVES: To determine the prevalence and associated factors of current smoking among medical students. METHODS: Cross sectional study was conducted during January and February 2009 among 333 study subjects selected randomly from four batches of a teaching institution. Subjects were administered a self administered pre tested questionnaire and smoking status was assessed as per the criteria laid down by WHO. Proportion, chi square test and multiple logistic regression analysis were used for statistical analysis. RESULTS: The prevalence of current smoking was found to be 22.4% (67). There were widespread deficiencies in knowledge of smoking among students of different classes, as an important causal factor in many diseases like gastro intestinal malignancy, heart problems, asthma, and emphysema. It was found that only half of them were willing to quit smoking (33). Fourth year students (OR=2.54) and presence of peer pressure (OR=21.91) had independent significant association with current smoking. CONCLUSION: Prevalence of smoking among medical students is high that warrants adoption of comprehensive smoking control interventions among them.