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The conformational properties of AT1 antagonist valsartan have been analyzed both in solution and at the binding site of the receptor. Low energy conformations of valsartan in solution were explored by NMR spectroscopy and molecular modeling studies. The NMR results showed the existence of two distinct and almost isoenergetic conformations for valsartan (cis:trans ratio around the amide bond ∼40:60) that coalesce at the temperature range of 55-60 °C in agreement with previous in solution conformational analysis study (Fang et al. Magn. Reson. Chem. 2007, 45, 929-936). Quantum mechanics and ONIOM calculations revealed that the bulky valsartan substituents actually contribute to stabilization of the transition state for interconversion. In silico docking and Molecular Dynamic studies were applied to study binding of valsartan at the AT1 receptor site models, explicitly solvated and embedded in lipid bilayers and solvent molecules. These studies revealed that the majority of docked poses adopted a trans (major) conformation. Of paramount and maybe biological importance are the MD simulations results which showed that the two acidic groups of valsartan are bridged through LYS199 enabling it for multiple hydrogen bond interactions. In a lipid bilayer environment these interactions are enhanced, designating the important role of lipid bilayers for the better binding of valsartan and its stabilization at the active site

This prospective study assessed the Surgical Site Infection (SSI) rates in General Surgery and the microorganisms isolated. From January 2000 to October 2000, 898 patients were enrolled and electively operated in a General Surgery Clinic in Athens, Greece. Pre-coded questionnaires were used. The diagnosis and surveillance of SSIs was made by the surgeon-investigator who interviewed the patients. Patients were monitored during hospitalization and post-discharge for 30 days. Overall, 402 patients underwent a clean and 496 patients underwent a clean-contaminated operation. A total of 17 SSIs (4.2%) were observed in clean and 64 SSIs (12.9%) in clean-contaminated operations. Microorganisms were isolated in 36 of 65 (55%) of cases that microbiological evaluation was performed. Staphylococcus aureus was the commonest microorganism isolated, followed by Escherichia coli and Pseudomonas aeruginosa. SSI rates were higher than expected and most SSIs, 43 of 81 (53.1%), were diagnosed post-operatively. Post-discharge surveillance of SSIs remains a critical issue. Health care professionals, especially surgeons, should participate in surveillance networks and be aware of the results so to take appropriate action.

p53 protein promotes apoptosis, whereas Bcl-2 family proteins have an antiapoptotic function. This study determines the predictive value of selected clinical and histopathological factors in correlation with the expression of p53, Bcl-2, and Bcl-X(L) proteins in esophageal squamous cell carcinomas (SCCs). Paraffin-embedded sections from 19 surgically resected primary esophageal SCCs were examined by immunohistochemistry. p53 expression was related to degree of tumor differentiation (P = 0.044). Bcl-2 expression was associated with regional lymph node metastasis (P = 0.053), whereas Bcl-X(L) expression was correlated with distant metastasis (P = 0.060) and with the expression of Bcl-2 protein (P = 0.068). p53 and Bcl-2 family proteins may help to estimate the properties of esophageal SCCs and provide useful information to the oncologist for the selection of patients for intensive combined therapy modalities with curative intention or for palliative therapy. Int Surg

Our knowledge regarding the biology of the gastroesophageal junction adenocarcinomas is still incomplete. Paraffin-embedded sections from 31 surgically resected primary cardia adenocarcinomas were examined by immunohistochemistry. Statistical analysis showed that Bcl-2 expression was significantly correlated with the age of the patients (P = 0.043), whereas Bcl-X(L) expression was inversely correlated with Bcl-2 expression (P = 0.021). An inverse correlation of high statistical significance was also found between p53 and Bcl-2 expression (P = 0.000). Fas expression was highly correlated with tumor stage (P = 0.006), degree of differentiation (P = 0.044), and the stage of the disease (P = 0.029). A significant correlation was also observed between the expression levels of WAF1 and Fas (P = 0.037), Fas and Bcl-X(L) (P = 0.018), and WAF1 and p53 (P = 0.018). These proteins may contribute to the estimation of the properties of adenocarcinomas of the gastroesophageal junction, facilitating prognosis of cancer patients treated by multimode therapy. Int Surg

AIAA Paper No. 2003-6549, San Diego, California, Sept. 2003. Live demonstration of the MAV in a nearby park In this paper the development and flight testing of flapping-wing propelled, radio-controlled micro air vehicles are described. The vehicles consist of a fixed-wing and a pair of flapping wings immediately downstream of the fixed-wing which flap in counterphase to provide a mechanically and aerodynamically balanced platform and increased efficiency. The models weigh as little as 13 grams, with a 27 cm span and 18 cm length and will fly for about 20 minutes on a 135 mAh Li-Poly battery. Stable flight at speeds between 2 and 5 m/s has been demonstrated, and the models are essentially stall-proof while under power due to the flow-entrainment effect of the flapping-wing pair.

Glucocorticoid induced osteoporosis has been associated with high doses and it has been partially attributed to decreased absorption and to increased calcium excretion. The present study examined the effect of low but effective doses of methylprednisolone (MP) on calcium balance and on skeleton in rats. Total duration of the experiment 29 days. Thirty-one male Wistar rats (MP group) were injected with 4mg/kg body weight MP sc at the Ist, 11th and 20th day of the experiment and 28 rats (C group) were used as matched controls. The Ist, 11th and 20th day of the experiment rats were placed in individual metabolic cages for three days. Food and water consumption were measured at the 2nd and 3rd days after each injection; urine and faeces were collected at the same days for calcium estimation. Calcium intake and excretion after each injection was significantly lower in the MP group as compared to controls. A statistically significant positive correlation between calcium consumption and calcium excretion was found in both groups resulting in a negative final balance. Rats were killed the 29th day. Adrenal weight was statistically significant lower in MP group (p