Consensus guidelines for enhanced recovery after gastrectomy: Enhanced Recovery After Surgery (ERAS®) Society recommendations

BACKGROUND

Application of evidence-based perioperative care protocols reduces complication rates, accelerates recovery and shortens hospital stay. Presently, there are no comprehensive guidelines for perioperative care for gastrectomy.

METHODS

An international working group within the Enhanced Recovery After Surgery (ERAS®) Society assembled an evidence-based comprehensive framework for optimal perioperative care for patients undergoing gastrectomy. Data were retrieved from standard databases and personal archives. Evidence and recommendations were classified according to the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system and were discussed until consensus was reached within the group. The quality of evidence was rated 'high', 'moderate', 'low' or 'very low'. Recommendations were graded as 'strong' or 'weak'.

RESULTS

The available evidence has been summarized and recommendations are given for 25 items, eight of which contain procedure-specific evidence. The quality of evidence varies substantially and further research is needed for many issues to improve the strength of evidence and grade of recommendations.

CONCLUSION

The present evidence-based framework provides comprehensive advice on optimal perioperative care for the patient undergoing gastrectomy and facilitates multi-institutional prospective cohort registries and adequately powered randomized trials for further research.

A fully automated, 'thimble-size' scanning tunnelling microscope

A novel, fully automated high-stability, high-eigenfrequency scanning tunnelling microscope (STM) has been developed. Its key design feature is the application of two piezoelectric ceramic tubes, one for the x-y-z motion of the tip and one for a linear motor ('nano-worm') used for the coarse positioning of the tip relative to the specimen. By means of the nano-worm, the tip can be advanced in steps between 16 and 0.2 nm. The walking distance is greater than 2 mm, with a maximum speed of 2000 steps/s. The nano-worm positioning implies that this STM is fully controlled by electronic means, and that no mechanical coupling is needed, which makes operation of the STM extremely convenient. The axial-symmetry construction is rigid, small and temperature-compensated, yielding reduced sensitivity to mechanical and acoustic vibrations and temperature variations. The sample is simply placed on a piece of invar which surrounds the scanner tube and the nano-worm and is held by gravity alone. This allows for easy sample mounting. The performance of the microscope has been tested in air by imaging a variety of surfaces, including graphite and biological samples.

Structural properties of a phosphatidylcholine-cholesterol system as studied by small-angle neutron scattering: ripple structure and phase diagram

Small-angle neutron scattering has been used to study structural features of lamellar bilayer membranes of dimyristoylphosphatidylcholine (DMPC) and DMPC mixed with various amount of cholesterol. The studies were recorded at a fixed hydration level of 17% 2H2O, i.e. just below saturation. Bragg reflections gives information on the ripple structure and on the bilayer periodicity. The crystalline Lc phase, which was stabilized after long time storage at low temperature, exhibits major small angle scattering when cholesterol is mixed into the membrane. The intermediate P beta' gel-phase, which is characteristic by the rippled structure, is dramatically stabilized by the introduction of cholesterol. The ripple structure depends significantly both on the cholesterol content and on the temperature. At high temperatures, T greater than 15 degrees C, the inverse ripple periodicity varies basically linearly with cholesterol content, and approach zero (i.e. periodicity goes to infinite) at 20 mol% cholesterol, approximately. At lower temperatures the correlation is more complex. The data indicate additional phase boundaries below 2 mol% and at approx. 8 mol%. Secondary rippled structures are observed in the low temperature L beta'-phase for cholesterol content below approx. 8 mol%. The data gives detailed insight into the phosphatidylcholine cholesterol phase diagram, which is discussed on the basis of a simple model in which the cholesterol complexes are fixed to the defect stripes of the rippled structure.

Influence of Alcohol on the Behavior of Sodium Dodecylsulfate Micelles

The effect of medium chain alcohol molecules on the size and shape of sodium dodecylsulfate micelles, and on the self-diffusion coefficient of the surfactant and alcohol, has been investigated by means of small angle neutron scattering (SANS), and Fourier transform pulsed field gradient spin echo (FT-PGSE) nuclear magnetic resonance measurements. All measurements were done in D2O containing a sodium chloride concentration of 0.4 mol/kg, and a surfactant concentration of 0.04 mol/kg. The alcohols used were 1-propanol, 1-butanol, and 1-pentanol. The data obtained from the different techniques agrees qualitatively. The results show that propanol successively breaks down the micelles while pentanol brings about a structural change toward large wormlike aggregates. Butanol shows a highly complex behavior on the structure of the micelles and can decrease and increase the size of the aggregates, depending on the added alcohol concentration range. All analyzed solutions show a distribution of the alcohol between the aqueous bulk solution and the palisade layer of the micelles, resulting in an increased "hydration" of D2O in the micellar surface. Moreover, the structural changes of the micelles indicate that butanol and pentanol solubilize in the micellar core in the high molality range, near the end of the solubility limit. Propanol is apparently too hydrophilic to do so. Copyright 1998 Academic Press.

Quantitative Gd-DOTA uptake from cerebrospinal fluid into rat brain using 3D VFA-SPGR at 9.4T

PURPOSE

We propose a quantitative technique to assess solute uptake into the brain parenchyma based on dynamic contrast-enhanced MRI (DCE-MRI). With this approach, a small molecular weight paramagnetic contrast agent (Gd-DOTA) is infused in the cerebral spinal fluid (CSF) and whole brain gadolinium concentration maps are derived.

METHODS

We implemented a 3D variable flip angle spoiled gradient echo (VFA-SPGR) longitudinal relaxation time (T1) technique, the accuracy of which was cross-validated by way of inversion recovery rapid acquisition with relaxation enhancement (IR-RARE) using phantoms. Normal Wistar rats underwent Gd-DOTA infusion into CSF via the cisterna magna and continuous MRI for approximately 130 min using T1-weighted imaging. Dynamic Gd-DOTA concentration maps were calculated and parenchymal uptake was estimated.

RESULTS

In the phantom study, T1 discrepancies between the VFA-SPGR and IR-RARE sequences were approximately 6% with a transmit coil inhomogeneity correction. In the in vivo study, contrast transport profiles indicated maximal parenchymal retention of approximately 19% relative to the total amount delivered into the cisterna magna.

CONCLUSION

Imaging strategies for accurate 3D contrast concentration mapping at 9.4T were developed and whole brain dynamic concentration maps were derived to study solute transport via the glymphatic system. The newly developed approach will enable future quantitative studies of the glymphatic system in health and disease states. Magn Reson Med 79:1568-1578, 2018. © 2017 International Society for Magnetic Resonance in Medicine.

Structure of RecA-DNA complexes studied by combination of linear dichroism and small-angle neutron scattering measurements on flow-oriented samples

By combining anisotropy of small-angle neutron scattering (SANS) and optical anisotropy (linear dichroism, l.d.) on flow-oriented RecA-DNA complexes, the average DNA-base orientation has been determined in RecA complexes with double-stranded (ds) as well as single-stranded (ss) DNA. From the anisotropy of the two-dimensional SANS intensity representation, the second moment orientation function S is obtained. Knowledge of S is crucial for the interpretation of l.d. spectra in terms of orientation of the DNA bases and the aromatic amino acid residues. The DNA-base planes are essentially perpendicular to the fibre axis of the complex between RecA and dsDNA in the presence of cofactor ATP gamma S. A somewhat tilted base geometry is found for the RecA-ATP gamma S complexes with single-stranded poly(dT) and poly(d epsilon A). This behaviour contrasts the RecA-ssDNA complex formed without cofactor which displays a poor orientation of the bases. Well-ordered bases in the ssDNA-RecA complex is possibly reflecting the role of RecA in preparing a nucleotide strand for base-pairing in the search-for-homology process. While the central SANS intensity is essentially independent of the pitch of the helical complex, a secondary intensity maximum, which becomes focused upon flow orientation, is found to be a sensitive measure of the pitch. The pitch values for the complexes compare well with cryo-electron microscopy results but are slightly larger than those seen for uranyl-stained samples.

Endogenous endothelial cell nitric-oxide synthase modulates apoptosis in cultured breast cancer cells and is transcriptionally regulated by p53

Nitric oxide can both stimulate and suppress apoptosis. By reverse transcriptase-polymerase chain reaction and sequencing we show that human breast cancer (MCF-7) cells express endothelial cell nitric-oxide synthase (ecNOS), but not other nitric-oxide synthase isoforms. Inhibition of ecNOS activity in MCF-7 cells increased tumor cell apoptosis, and this effect was also seen following treatment with an NO scavenger. In addition, low concentrations of the NO donor sodium nitroprusside inhibited, whereas high concentrations stimulated MCF-7 cell apoptosis. The ecNOS promoter was found to contain a specific binding site for the apoptosis-regulating protein p53. In co-transfection studies wild-type, but not mutant, p53 down-regulated transcription of an ecNOS promoter-luciferase reporter gene construct. In addition, NO donors up-regulated p53 protein levels in MCF-7 cells. These data point to a previously unrecognized p53-dependent regulation of ecNOS expression that may be important both for regulating apoptosis and for avoiding the generation of genotoxic quantities of NO.

The epidemiology of hospital-referred head injury in northern Norway

This retrospective population-based survey describes the epidemiology of head injury in a defined population in Northern Norway. It includes all 247 patients with head injury referred to the University Hospital of Tromsø, Norway, during 1993. Head injury was defined as physical damage to the brain or skull caused by external force. The annual incidence rate of hospital-referred head injury was 229/100,000 population with a male preponderance of 1.7:1.0. The cause was a fall in 62%, road traffic accident in 21% and assault in 7% of the cases. The observed incidence rate is low despite the use of wide inclusion criteria, probably due to a decrease in road traffic accidents. A further decrease in the number of head injuries in our region may be achieved by preventing falls.

Evidence for elongation of the helical pitch of the RecA filament upon ATP and ADP binding using small-angle neutron scattering

Structural changes of the RecA filament upon binding of cofactors have been investigated by small-angle neutron scattering. Both ATP and ADP increased the helical pitch of the RecA homopolymer, which is observed to be 7 nm in the absence of any cofactor. The binding of ATP altered the pitch to 9 nm, whereas the binding of ADP only produced a pitch of 8.2 nm. The pitch determined for the RecA complex with the ATP analog adenosine 5'-[gamma-thio]triphosphate was similar to that found with ATP. Thus, at least three, somewhat different. RecA helical filamentous structures may form in solution. The binding of DNA to RecA did not alter the pitch significantly, indicating that the cofactor binding is the determining factor for the size of the helical pitch of the RecA filament. We also found that elongation of the helical pitch is a necessary, but not a sufficient condition, for the coprotease activity of RecA. The presence of acetate or glutamate ions is also required. The pitch of the ADP.RecA filament is in agreement with that found in the crystal structure. This correlation indicates that this structure corresponds to that of the ADP.RecA filament in solution, although this is not the species active in recombination.

Breast feeding and the development of type 1 diabetes mellitus

A case-control study was conducted to study the proposed inverse relationship between breast feeding and incidence of Type 1 diabetes mellitus. All Danish diabetic men born in Copenhagen during 1959-1964 and/or residing there for the first year of life (n = 119) were identified and a search made for their post-natal health visitor records. These include data on birth weight, birth length, immunizations, and feeding habits. A total of 77 cases were re-identified. No differences were found with respect to clinical characteristics between these cases and those not identified. For each diabetic subject, two control children with date of birth identical to the diabetic cases were drawn from health visitor records. Cases and controls did not differ with respect to maternal age, or birth weight or length. Overall, the statistical analysis failed to confirm the hypothesis of an association between duration of breast feeding and subsequent diabetes risk.

Increased NADPH-diaphorase activity in canine myxomatous mitral valve leaflets

Comparable pathological changes in the mitral valve have been described in dogs, pigs and human patients with myxomatous mitral valve disease (MMVD), i.e., primary mitral valve prolapse. The progressive myxomatous changes are probably a response to repeated impact on the leaflets, and endothelial stress or damage probably plays a central role in the pathogenesis. Little, however, is known about the vasoactive substances that mediate the subendothelial changes. The aim of this study was to investigate the expression of nitric oxide synthase (NOS) in canine mitral valve leaflets and to relate the findings to MMVD changes. The mitral valve was taken post mortem from 12 dogs (six males and six females) and a whole valve NADPH (the reduced form of nicotinamide-adenine dinucleotide phosphate) diaphorase (NADPH-d) reaction was performed. Macroscopical (semiquantitative) and microscopical (computer image analysis) evaluations of the staining due to NADPH-d activity were performed at four specific areas of the valve and related to microscopical signs of MMVD and gross signs of thickening or prolapse, or both. Macroscopically, the NADPH-d colour grade was correlated with the degree of MMVD (P=0.01). In addition, endothelial NADPH-d staining intensity was correlated with macroscopical signs of disease (P=0.004) as well as with collagen degeneration (P=0.008) and deposition of mucopolysaccharides (P=0.02). Age, gender and specific area of the valve did not seem to influence the NADPH-d activity. In conclusion, increased NADPH-d activity, suggesting increased NOS expression, was found in areas of the mitral valve with myxomatous changes. This indicates that nitric oxide (NO) may play a role in the pathogenesis of MMVD in dogs.