From 3-Port to New Laparoendoscopic Single-Site (LESS) Cholecystectomy : A Critical Analysis of Available Evidence.

In recent years, laparoendoscopic single-site surgery (LESS) has gained greater interest and diffusion for the treatment of gallstones. This critical review aims to evaluate the feasibility and safety of LESS cholecystectomy versus the 3-port technique (TPT) through a comparative analysis of 5 parameters: mean operative time, intraoperative and postoperative complications, conversion to open, conversion to the 4-trocar technique and postoperative hospital stay. The authors performed a systematic search of the medical literature through a search of PubMed and Ovid EMBASE. Inclusion criteria were as follows: publication date between January 1, 2005, and December 31, 2010; English or Italian language; human participants and series of 20 operations or more. There were 5 manuscripts meeting the inclusion criteria for TPT and 23 for LESS. Only one prospective randomized controlled trial comparing TPT and LESS was identified. Operative time is significantly longer in the single-incision group. Complications and conversion rates to the 4-port technique are higher in LESS. Postoperative hospital stay is similar in the 2 groups. Rate of conversion to open is higher in TPT. Despite the number of publications on LESS cholecystectomy, the vast majority of data available in the literature are from small case series without any comparative data. Although LESS cholecystectomy is a fashionable technique there are few data available for an evidence-based determination as to the real benefits of this technique. Well-designed comparative studies are suggested to validate the clinical benefits and ensure that there are no new complications or added costs associated with the new technique

Indications to total thyroidectomy for multinodular goiter in old patients

Background: In Western society, the percentage of elderly people is continually growing. The prevalence of goiter increases with the age and it is estimated that 90% of women over 60 years old and 60% of men over 80 years old have a relief of thyroid nodules. This has great importance for these patients, because the incidence of malignant transformation is higher than younger ones and these are often tumor very aggressive patterns. If thyroidectomy is indicated for patients with suspected neoplasm and severe obstructive symptoms, their surgery should not be delayed since a late urgent operation could raise morbidity and mortality risk. The main indications for young patients are due to obstructive and metabolic causes over and above suspected cancer. Total thyroidectomy is considered by many authors as the treatment of choice. Materials and methods: 75 elderly patients were submitted to thyroidectomy. The indications were metabolic (42.6%), obstructive (32%) and for suspected cancer (25.4%). Results: The most frequent complications observed with respect to young patients in different series have been cardiovascular, pulmonary or urological. Regarding the complications directly related to thyroidectomy, there were no differences compared to younger groups, except transient complications (hypoparathyroidism, seroma). In our experience, the main complication was represented by hypocalcemia (30.6%), permanent in 8% of cases. Cancer was relieved in 21.3% of cases. Prognosis has been excellent in most cases, with immediate remission of symptoms related to thyrotoxicosis and to tracheal and esophageal compression in almost all symptomatic patients. Conclusions: Age is an independent prognostic factor for cancers. It has been demonstrated that elderly patients with PTC that are operated have better prognosis and quality of life due to the resolution of dyspnea and dysphagia. In our experience, we think that age is not a contraindication to thyroid surgery

High efficiency dye-sensitized solar cells exploiting sponge-like ZnO nanostructures

DSCs based on sponge-like ZnO photoanodes showing conversion efficiency of 6.67% and superior transport properties compared with standard TiO2 nanoparticle

Acid sensing by the Drosophila olfactory system.

The odour of acids has a distinct quality that is perceived as sharp, pungent and often irritating. How acidity is sensed and translated into an appropriate behavioural response is poorly understood. Here we describe a functionally segregated population of olfactory sensory neurons in the fruitfly, Drosophila melanogaster, that are highly selective for acidity. These olfactory sensory neurons express IR64a, a member of the recently identified ionotropic receptor (IR) family of putative olfactory receptors. In vivo calcium imaging showed that IR64a+ neurons projecting to the DC4 glomerulus in the antennal lobe are specifically activated by acids. Flies in which the function of IR64a+ neurons or the IR64a gene is disrupted had defects in acid-evoked physiological and behavioural responses, but their responses to non-acidic odorants remained unaffected. Furthermore, artificial stimulation of IR64a+ neurons elicited avoidance responses. Taken together, these results identify cellular and molecular substrates for acid detection in the Drosophila olfactory system and support a labelled-line mode of acidity coding at the periphery

Synthesis, antitubercular activity and mechanism of resistance of highly effective thiacetazone analogues

Defining the pharmacological target(s) of currently used drugs and developing new analogues with greater potency are both important aspects of the search for agents that are effective against drug-sensitive and drug-resistant Mycobacterium tuberculosis. Thiacetazone (TAC) is an anti-tubercular drug that was formerly used in conjunction with isoniazid, but removed from the antitubercular chemotherapeutic arsenal due to toxic side effects. However, several recent studies have linked the mechanisms of action of TAC to mycolic acid metabolism and TAC-derived analogues have shown increased potency against M. tuberculosis. To obtain new insights into the molecular mechanisms of TAC resistance, we isolated and analyzed 10 mutants of M. tuberculosis that were highly resistant to TAC. One strain was found to be mutated in the methyltransferase MmaA4 at Gly101, consistent with its lack of oxygenated mycolic acids. All remaining strains harbored missense mutations in either HadA (at Cys61) or HadC (at Val85, Lys157 or Thr123), which are components of the bhydroxyacyl-ACP dehydratase complex that participates in the mycolic acid elongation step. Separately, a library of 31 new TAC analogues was synthesized and evaluated against M. tuberculosis. Two of these compounds, 15 and 16, exhibited minimal inhibitory concentrations 10-fold lower than the parental molecule, and inhibited mycolic acid biosynthesis in a dose-dependent manner. Moreover, overexpression of HadAB HadBC or HadABC in M. tuberculosis led to high level resistance to these compounds, demonstrating that their mode of action is similar to that of TAC. In summary, this study uncovered new mutations associated with TAC resistance and also demonstrated that simple structural optimization of the TAC scaffold was possible and may lead to a new generation of TAC-derived drug candidates for the potential treatment of tuberculosis as mycolic acid inhibitors

Stroke genetics: prospects for personalized medicine.

Epidemiologic evidence supports a genetic predisposition to stroke. Recent advances, primarily using the genome-wide association study approach, are transforming what we know about the genetics of multifactorial stroke, and are identifying novel stroke genes. The current findings are consistent with different stroke subtypes having different genetic architecture. These discoveries may identify novel pathways involved in stroke pathogenesis, and suggest new treatment approaches. However, the already identified genetic variants explain only a small proportion of overall stroke risk, and therefore are not currently useful in predicting risk for the individual patient. Such risk prediction may become a reality as identification of a greater number of stroke risk variants that explain the majority of genetic risk proceeds, and perhaps when information on rare variants, identified by whole-genome sequencing, is also incorporated into risk algorithms. Pharmacogenomics may offer the potential for earlier implementation of 'personalized genetic' medicine. Genetic variants affecting clopidogrel and warfarin metabolism may identify non-responders and reduce side-effects, but these approaches have not yet been widely adopted in clinical practice

The Cyst Nematode SPRYSEC Protein RBP-1 Elicits Gpa2- and RanGAP2-Dependent Plant Cell Death

Plant NB-LRR proteins confer robust protection against microbes and metazoan parasites by recognizing pathogen-derived avirulence (Avr) proteins that are delivered to the host cytoplasm. Microbial Avr proteins usually function as virulence factors in compatible interactions; however, little is known about the types of metazoan proteins recognized by NB-LRR proteins and their relationship with virulence. In this report, we demonstrate that the secreted protein RBP-1 from the potato cyst nematode Globodera pallida elicits defense responses, including cell death typical of a hypersensitive response (HR), through the NB-LRR protein Gpa2. Gp-Rbp-1 variants from G. pallida populations both virulent and avirulent to Gpa2 demonstrated a high degree of polymorphism, with positive selection detected at numerous sites. All Gp-RBP-1 protein variants from an avirulent population were recognized by Gpa2, whereas virulent populations possessed Gp-RBP-1 protein variants both recognized and non-recognized by Gpa2. Recognition of Gp-RBP-1 by Gpa2 correlated to a single amino acid polymorphism at position 187 in the Gp-RBP-1 SPRY domain. Gp-RBP-1 expressed from Potato virus X elicited Gpa2-mediated defenses that required Ran GTPase-activating protein 2 (RanGAP2), a protein known to interact with the Gpa2 N terminus. Tethering RanGAP2 and Gp-RBP-1 variants via fusion proteins resulted in an enhancement of Gpa2-mediated responses. However, activation of Gpa2 was still dependent on the recognition specificity conferred by amino acid 187 and the Gpa2 LRR domain. These results suggest a two-tiered process wherein RanGAP2 mediates an initial interaction with pathogen-delivered Gp-RBP-1 proteins but where the Gpa2 LRR determines which of these interactions will be productive

Energy Linearity and Resolution of the ATLAS Electromagnetic Barrel Calorimeter in an Electron Test-Beam

A module of the ATLAS electromagnetic barrel liquid argon calorimeter was exposed to the CERN electron test-beam at the H8 beam line upgraded for precision momentum measurement. The available energies of the electron beam ranged from 10 to 245 GeV. The electron beam impinged at one point corresponding to a pseudo-rapidity of eta=0.687 and an azimuthal angle of phi=0.28 in the ATLAS coordinate system. A detailed study of several effects biasing the electron energy measurement allowed an energy reconstruction procedure to be developed that ensures a good linearity and a good resolution. Use is made of detailed Monte Carlo simulations based on Geant which describe the longitudinal and transverse shower profiles as well as the energy distributions. For electron energies between 15 GeV and 180 GeV the deviation of the measured incident electron energy over the beam energy is within 0.1%. The systematic uncertainty of the measurement is about 0.1% at low energies and negligible at high energies. The energy resolution is found to be about 10% sqrt(E) for the sampling term and about 0.2% for the local constant term

Position resolution and particle identification with the ATLAS EM calorimeter

In the years between 2000 and 2002 several pre-series and series modules of the ATLAS EM barrel and end-cap calorimeter were exposed to electron, photon and pion beams. The performance of the calorimeter with respect to its finely segmented first sampling has been studied. The polar angle resolution has been found to be in the range 50-60 mrad/sqrt(E (GeV)). The neutral pion rejection has been measured to be about 3.5 for 90% photon selection efficiency at pT=50 GeV/c. Electron-pion separation studies have indicated that a pion fake rate of (0.07-0.5)% can be achieved while maintaining 90% electron identification efficiency for energies up to 40 GeV.Comment: 32 pages, 22 figures, to be published in NIM