Routine preoperative biliary drainage in patients undergoing surgery for cancer of the pancreatic head increases the rate of complications. (Current Controlled Trials number, ISRCTN31939699.)

Many indirect methods have been developed to study the constitution and conformation of macromolecules inside the living cell. Direct analysis by Raman spectroscopy is an ideal complement to techniques using directly labelled fluorescent probes or of indirect labelling with mono- and polyclonal antibodies. The high information content of Raman spectra can characterize biological macromolecules both in solution and in crystals. The positions, intensities and linewidths of the Raman lines (corresponding to vibrational energy levels) in spectra of DNA-protein complexes yield information about the composition, secondary structure and interactions of these molecules, including the chemical microenvironment of molecular subgroups. The main drawback of the method is the low Raman scattering cross-section of biological macromolecules, which until now has prohibited studies at the level of the single cell with the exception of (salmon) sperm heads, in which the DNA is condensed to an exceptionally high degree. Ultraviolet-resonance Raman spectroscopy has been used to obtain single cell spectra (and F. Sureau and P. Y. Turpin, personal communication), but in this method absorption of laser light may impair the integrity of the sample. We have avoided this problem in developing a novel, highly sensitive confocal Raman microspectrometer for nonresonant Raman spectroscopy. Our instrument makes it possible to study single cells and chromosomes with a high spatial resolution (approximately less than 1 micron 3).

Intestinal microbiota alterations in obese subjects are associated with local and systemic inflammation, suggesting that the obesity-related microbiota composition has a proinflammatory effect.

Nonresonant confocal Raman imaging has been used to map the DNA and the protein distributions in individual single human cells. The images are obtained on an improved homebuilt confocal Raman microscope. After statistical analysis, using singular value decomposition, the Raman images are reconstructed from the spectra covering the fingerprint region. The data are obtained at a step interval of approximately 250 nm and cover a field from 8- to 15- micro m square in size. Dwell times at each pixel are between 0.5 and 2 s, depending on the nature and the state of the cell under investigation. High quality nonresonant Raman images can only be obtained under these conditions using continuous wave high laser powers between 60 and 120 mW. We will present evidence that these laser powers can still safely be used to recover the chemical distributions in fixed cells. The developed Raman imaging method is used to image directly, i.e., without prior labeling, the nucleotide condensation and the protein distribution in the so-called nuclear fragments of apoptotic HeLa cells. In the control (nonapoptotic) HeLa cells, we show, for the first time by Raman microspectroscopy, the presence of the RNA in a cell nucleus.

We show that standard silicon nitride cantilevers can be used for tapping mode atomic force microscopy (AFM) in air, provided that the energy of the oscillating cantilever is sufficiently high to overcome the adhesion of the water layer. The same cantilevers are successfully used for tapping mode AFhif in liquid. Acoustic modes in the liquid excite the canti1eve.r. On soft samples, e.g., biological material, this tapping mode AFM is much more gentle than the regular contact mode AFM. Not only is the destructive infuence of the lateral forces minimized, but more important, the intrinsic viscoelastic properties of the sample itself are effectively used to "harden" the soft sample.

A Raman microprobe has been used to measure the surface-enhanced Raman spectra of adenine, guanine, cytosine and thymine. Comparison of the SERS spectrum with solution spectra shows that some line positions are not influenced by the adsorption process while others show large shifts. In the SERS spectrum new lines, not visible in the solution spectrum, appear while some lines visible in the solution spectrum are not enhanced to a detectable level and are therefore not seen in SERS. The relative intensities are changed owing to an apparently vibrationdependent enhancement factor. A line-broadening effect occurs for most lines except carbonyl stretching vibrations in cytosine and thymine. All SERS spectra show increased contributions of bending vibrations and side-chain groups. In particular, amino group vibrations in adenine and cytosine are clearly visible. Comparison of the shape and intensity of the carbonyl stretching vibrations in cytosine, thymine and guanine show important differences. It is hypothesized that these differences indicate differences in the orientation of these groups with respect to the surface.

In 2012, an outstanding expert panel derived from IFSO-EC (International Federation for the Surgery of Obesity -European Chapter) and EASO (European Association for the Study of Obesity), composed by key representatives of both Societies including past and present presidents together with EASO's OMTF (Obesity Management Task Force) chair, agreed to devote the joint Medico-Surgical Workshop of both institutions to the topic of metabolic surgery as a pre-satellite of the 2013 European Congress on Obesity (ECO) to be held in Liverpool given the extraordinarily advancement made specifically in this field during the past years. It was further agreed to revise and update the 2008 Interdisciplinary European Guidelines on Surgery of Severe Obesity produced in cooperation of both Societies by focusing in particular on the evidence gathered in relation to the effects on diabetes during this lustrum and the subsequent changes that have taken place in patient eligibility criteria. The expert panel composition allowed the coverage of key disciplines in the comprehensive management of obesity and obesity-associated diseases, aimed specifically at updating the clinical guidelines to reflect current knowledge, expertise and evidence-based data on metabolic and bariatric surgery.

The immune system in vertebrates senses exogenous and endogenous danger signals by way of complex cellular and humoral processes, and responds with an inflammatory reaction to combat putative attacks. A strong protective immunity is imperative to prevent invasion of pathogens; however, equivalent responses to commensal flora and dietary components in the intestine have to be avoided. The autonomic nervous system plays an important role in sensing luminal contents in the gut by way of hard-wired connections and chemical messengers, such as cholecystokinin (CCK). Here, we report that ingestion of dietary fat stimulates CCK receptors, and leads to attenuation of the inflammatory response by way of the efferent vagus nerve and nicotinic receptors. Vagotomy and administration of antagonists for CCK and nicotinic receptors significantly blunted the inhibitory effect of high-fat enteral nutrition on hemorrhagic shock-induced tumor necrosis factor-α and interleukin-6 release (P < 0.05). Furthermore, the protective effect of high-fat enteral nutrition on inflammation-induced intestinal permeability was abrogated by vagotomy and administration of antagonists for CCK and nicotinic receptors. These data reveal a novel neuroimmunologic pathway, controlled by nutrition, that may help to explain the intestinal hyporesponsiveness to dietary antigens, and shed new light on the functionality of nutrition.