Nano-TiO2 particles impair adhesion of airway epithelial cells to fibronectin

Titanium dioxide engineered nanoparticles (nano-TiO₂) are widely used in the manufacturing of a number of products. Due to their size (<100 nm), when inhaled they may be deposited in the distal lung regions and damage Clara cells. We investigated the mechanisms by which short-term (1-h) incubation of human airway Clara-like (H441) cells to nano-TiO₂ (6 nm in diameter) alters the ability of H441 cells to adhere to extracellular matrix. Our results show that 1 h post-incubation, there was a 3-fold increase of extracellular H₂O₂, increased intracellular oxidative stress as demonstrated by 2′,7′-dichlorodihydrofluorescein diacetate (DCFH-DA) oxidation, and a 5-fold increase of phosphor-ERK1/2 as measured by Western blotting. These changes were accompanied by a 25% decrease of H441 adherence to fibronectin (p < 0.05 compared to vehicle incubated H441 cells). Pretreatment with the ERK1/2 inhibitor U0126 for 3 h, partially prevented this effect. In conclusion, short-term exposure of H441 cells to nano-TiO₂ appears to reduce adherence to fibronectin due to oxidative stress and activation of ERK1/2.     

Fabrication of Diamond Based Sensors for Use in Extreme Environments

Electrical and magnetic sensors can be lithographically fabricated on top of diamond substrates and encapsulated in a protective layer of chemical vapor deposited single crystalline diamond. This process when carried out on single crystal diamond anvils employed in high pressure research is termed as designer diamond anvil fabrication. These designer diamond anvils allow researchers to study electrical and magnetic properties of materials under extreme conditions without any possibility of damaging the sensing elements. We describe a novel method for the fabrication of designer diamond anvils with the use of maskless lithography and chemical vapor deposition in this paper. This method can be utilized to produce diamond based sensors which can function in extreme environments of high pressures, high and low temperatures, corrosive and high radiation conditions. We demonstrate applicability of these diamonds under extreme environments by performing electrical resistance measurements during superconducting transition in rare earth doped iron-based compounds under high pressures to 12 GPa and low temperatures to 10 K.     

Molecular Docking Studies of Phytocompounds from the Phyllanthus Species as Potential Chronic Pain Modulators

The study of inflammatory pain has been one of the most rapidly advancing and expanding areas of pain research in recent years. Studies from our lab have demonstrated the chronic pain-modulating potential of the Phyllanthus species and their probable interaction with various inflammatory mediators involving enzymes like COX-2 and PGE synthase, cytokines like TNF-alpha and IL-1 beta, and with the NMDA receptor. Inflammatory mediators which play a crucial role in chronic inflammatory hyperalgesia and its subsequent modulation were selected for their interactions with 86 structurally diverse phytoconstituents identified from the Phyllanthus species.The docking analysis of the target proteins with the phytochemical ligands was performed using VLifeMDS software. The docking scores and analysis of the interactions of the phytocompounds with target proteins suggest that important molecules like lupeol, phyllanthin, hypopyllanthin, corilagin, epicatechin, and most of the other compounds have the ability to bind to multiple targets involved in inflammatory hyperalgesia.Our study strongly suggests that the findings of the present study could be exploited in the future for designing ligands in order to obtain novel molecules for the treatment and management of chronic pain.     

Longer duration of mechanical ventilation was found to be associated with ventilator-associated pneumonia in children aged 1 month to 12 years in India

ObjectivesTo determine primarily (1) the incidence of ventilator-associated pneumonia (VAP) among ventilated patients aged 1 month to 12 years and secondarily (2) the risk factors for VAP and (3) common organisms causing VAP.Study Design and SettingProspective study in a tertiary care center in India. Consecutive ventilated patients aged ≥1 month and ≤12 years and requiring mechanical ventilation (MV) for ≥48 hours were included after written informed parental consent. For the diagnosis of VAP, National Nosocomial Infections Surveillance System criteria of 1996 were used.ResultsIncidence of VAP among patients aged 1 month to 12 years was 36.2% (38/105; 95% confidence interval [CI]: 27, 46). In unconditional logistic regression analysis controlling for the presence of underlying illnesses, risk factor for VAP was >4 days of MV (adjusted odds ratio, 3.76; 95% CI: 1.41, 10.02; P = 0.008). Reintubation within 72 hours of extubation and more than two attendants at the time of recruitment showed increased tendency for the development of VAP but did not reach statistical significance. Endotracheal and endobronchial aspirates were positive for organism in 19.05% (20/105) and 37.14% (39/105) of patients, respectively.ConclusionAlmost one-third of ventilated patients develop VAP. Vigilance for the development of VAP has to be kept on those requiring >4 days of MV. Klebsiella and Staphylococcus aureus were common bacterial isolates in such patients.