Biocompatibility of Antifogging SiO-doped Diamond-Like Carbon Laparoscope Coatings.

Laparoscopes can suffer from fogging and contamination difficulties, resulting in a reduced field of view during surgery. A series of diamond-like carbon films, doped with SiO, were produced by pulsed laser deposition for evaluation as biocompatible, antifogging coatings. DLC films doped with SiO demonstrated hydrophilic properties with water contact angles under 40°. Samples subjected to plasma cleaning had improved contact angle results, with values under 5°. Doping the DLC films with SiO led to an average 40% decrease in modulus and 60% decrease in hardness. Hardness of the doped films, 12.0 - 13.2 GPa, was greater than that of the uncoated fused silica substrate, 9.2 GPa. The biocompatibility was assessed through CellTiter-Glo assays, with the films demonstrating statistically similar levels of cell viability when compared to the control media. The absence of ATP released by blood platelets in contact with the DLC coatings suggests in vivo hemocompatibility. The SiO doped films displayed improved transparency levels in comparison to undoped films, achieving up to an average of 80% transmission over the visible spectrum and an attenuation coefficient of 1.1 × 104 cm-1 at the 450 nm wavelength. The SiO doped DLC films show promise as a method of fog prevention for laparoscopes.

Patient Outcomes Following Emergency Bowel Resection for Inflammatory Bowel Disease and the Impact of Surgical Subspecialisation in the North of England: A Retrospective Cohort Study.

BACKGROUND: Management of inflammatory bowel disease (IBD) has changed considerably over recent years, which has coincided with increased subspecialisation amongst general surgeons. This study evaluated the demographics and outcomes of patients with IBD undergoing bowel resection and assessed for the potential impact of surgical subspecialisation. METHODS: Patient demographic, operative and outcome data were collected for patients undergoing a bowel resection secondary to IBD, admitted acutely to NHS trusts in the North of England between 2002 and 2016. The primary outcome of interest was 30-day post-operative mortality, with secondary outcomes: length of stay, stoma and anastomosis rates. RESULTS: A total of 913 patients were included in the study cohort. A reduction in the number of resections was noted over time (2002-2006: 361 vs. 2012-2016: 262). No change was observed for 30-day mortality over the study period (3.9%, p = 0.233). Length of stay was also unchanged (p = 0.949). Laparoscopic surgery was increasingly utilised (0.6% vs. 17.2%, p < 0.001) in recent years, and by colorectal subspecialists (p = 0.003). More patients were managed by a colorectal consultant latterly (2002-2006: 45.4% vs. 2012-2016: 63.7%, p < 0.001). There was no difference between colorectal and other subspecialists in mortality (p = 0.156), length of stay (p = 0.201), stoma (p = 0.629) or anastomosis (p = 0.659) rates, including following multivariable adjustment. CONCLUSION: The study demonstrated a significant reduction in the number of resections over time, increased utilisation of a laparoscopic approach and a shift towards the care of IBD surgical patients being by a colorectal subspecialist. However, these changes do not correspond with improved surgical outcomes.

Soil color indicates carbon and wetlands: developing a color-proxy for soil organic carbon and wetland boundaries on sandy coastal plains in South Africa.

A relationship between soil organic carbon and soil color is acknowledged-albeit not a direct one. Since heightened carbon contents can be an indicator of wetlands, a quantifiable relationship between color and carbon might assist in determining wetland boundaries by rapid, field-based appraisal. The overarching aim of this initial study was to determine the potential of top soil color to indicate soil organic carbon, and by extension wetland boundaries, on a sandy coastal plain in South Africa. Data were collected from four wetland types in northern KwaZulu-Natal in South Africa. Soil samples were taken to a depth of 300 mm in three transects in each wetland type and analyzed for soil organic carbon. The matrix color was described using a Munsell soil color chart. Various color indices were correlated with soil organic carbon. The relationship between color and carbon were further elucidated using segmented quantile regression. This showed that potentially maximal carbon contents will occur at values of low color indices, and predictably minimal carbon contents will occur at values of low or high color indices. Threshold values can thus be used to make deductions such as "when the sum of dry and wet Value and Chroma values is 9 or more, carbon content will be 4.79% and less." These threshold values can then be used to differentiate between wetland and non-wetland sites with a 70 to 100% certainty. This study successfully developed a quantifiable correlation between color and carbon and showed that wetland boundaries can be determined based thereon.

Upper gastrointestinal training in the UK and Ireland: a Roux Group Study.

INTRODUCTION: Surgical training programmes in the United Kingdom and Ireland (UK&I) are in a state of flux. This study aims to report the contemporary opinions of trainee and consultant surgeons on the current upper gastrointestinal (UGI) training model in the UK&I. METHODS: A questionnaire was developed and distributed via national UGI societies. Questions pertained to demographics, current training evaluation, perceived requirements and availability. RESULTS: A total of 241 responses were received with representation from all UK&I postgraduate training regions. The biggest discrepancies between rotation demand and national availability related to advanced/therapeutic endoscopy and robotic surgery, with 91.7% of respondents stating they would welcome greater geographical flexibility in training. The median suggested academic targets were 3-5 publications (trainee vs consultant <3 vs 3-5, p<0.001); <3 presentations (<3 vs 3-5, p=0.002); and 3-5 audits/quality improvement projects (<3 vs 3-5, p<0.001). Current operative requirements were considered achievable (87.6%) but inadequate for day one consultant practice (74.7%). Reassuringly, 76.3% deemed there was role for on-the-job operative training following consultant appointment. Proficiency in diagnostic endoscopy was considered a minimum requirement for Certificate of Completion of Training (CCT) yet the majority regarded therapeutic endoscopy competency as non-essential. The median numbers of index UGI operations suggested were comparable with the current curriculum requirements. Post-CCT fellowships were not considered necessary; however, the majority (73.6%) recognised their advantage. CONCLUSIONS: Current CCT requirements are largely consistent with the opinions of the UGI community. Areas for improvement include flexibility in geographical working and increasing national provisions for high-quality endoscopy training.

High resolution spectroscopy and the first global analysis of the Tetradecad region of methane 12CH4.

We present the first detailed analysis of the infrared spectrum of methane (12)CH4 in the so-called Tetradecad region from 2.1 to 1.6 µm (4760-6250 cm(-1)). New experimental high resolution FTIR spectra at 78 K and at room temperature combined with improved theoretical modeling have allowed quantum assignments to be greatly extended in this region. A global fit of all assigned lines of (12)CH4 in the 0-6200 cm(-1) region has been performed. In the end, 3012 line positions and 1387 intensities of 45 individual subbands of the Tetradecad were modeled up to J = 14. The root mean square deviations were 0.023 cm(-1) for line positions and 13.86% for line intensities in the Tetradecad region itself. Although this analysis is still preliminary, it is already sufficient to characterize the stronger bands throughout the whole of the Tetradecad. The calculated integrated intensity of the polyad is 1.399 × 10(-19) cm(-1)/(molecule cm(-2)) at 296 K. A "definitive" theoretical modeling of this spectral region of methane requires further work, but the present success substantially improves our understanding of methane spectroscopy as needed to interpret planetary atmospheres. Lines pertaining to three-fourths of the 60 sub-vibrational bands in this polyad have been assigned.

The impact of age on long-term survival following gastrectomy for gastric cancer.

INTRODUCTION: Gastrectomy remains the primary curative treatment modality for patients with gastric cancer. Concerns exist about offering surgery with a high associated morbidity and mortality to elderly patients. The study aimed to evaluate the long-term survival of patients with gastric cancer who underwent gastrectomy comparing patients aged <70 years with patients aged ≥70 years. METHODS: Consecutive patients who underwent gastrectomy for adenocarcinoma with curative intent between January 2000 and December 2017 at a single centre were included. Patients were stratified by age with a cut-off of 70 years used to create two cohorts. Log rank test was used to compare overall survival and Cox multivariable regression used to identify predictors of long-term survival. RESULTS: During the study period, 959 patients underwent gastrectomy, 520 of whom (54%) were aged ≥70 years. Those aged <70 years had significantly lower American Society of Anesthesiologists grades (p<0.001) and were more likely to receive neoadjuvant chemotherapy (39% vs 21%; p<0.001). Overall complication rate (p=0.001) and 30-day postoperative mortality (p=0.007) were lower in those aged <70 years. Long-term survival (median 54 vs 73 months; p<0.001) was also favourable in the younger cohort. Following adjustment for confounding variables, age ≥70 years remained a predictor of poorer long-term survival following gastrectomy (hazard ratio 1.35, 95% confidence interval 1.09, 1.67; p=0.006). CONCLUSIONS: Low postoperative mortality and good long-term survival were demonstrated for both age groups following gastrectomy. Age ≥70 years was, however, associated with poorer outcomes. This should be regarded as important factor when counselling patients regarding treatment options.

The junior doctor changeover effect: does it exist in general surgery?

INTRODUCTION: Junior doctor changeover has been perceived as a period of increased risk to patients. However, there is a paucity of contemporary evidence of this 'changeover effect'. The aim of this study was to evaluate the presence of an adverse patient effect during periods of junior doctor changeover. METHODS: Data were requested on all patients aged 18 years or older admitted acutely under General Surgery in the North of England between 2005 and 2016. This included patient characteristics, diagnoses, comorbidities, procedure codes, mortality and length of stay. Patients were included in the study if they were admitted during the 'changeover week'; defined as the first day of the changeover followed by the six subsequent days. For junior trainees (FY1-CT2), this is the first Wednesday of August, December and April each year. For higher surgical trainees (ST3-ST8), it is the first Wednesday in October. Another week, four weeks prior, was chosen as a historical comparator. RESULTS: In total, 61,714 patients were included in this study. Patient characteristics did not vary between the cohorts. There was no difference in 30-day mortality between changeover and non-changeover groups (2.5% vs 2.6%, p = 0.280) or length of stay (5.3 vs 5.2, p = 0.613). Changeover week was not a predictor of increased mortality (OR 1.06, p = 0.302) following multivariable adjustment. Further analysis of the first junior and higher specialty trainee periods, August and October, respectively, showed no significant difference for measured outcomes. CONCLUSIONS: This retrospective cohort study provides contemporary evidence that the 'changeover effect' does not exist in acute general surgical admissions in the UK.

Maternal influences on thiamine status of walleye Sander vitreus ova.

Concentrations of the various forms of thiamine (vitamin B(1) ) were determined in walleye Sander vitreus ova from three central North American lakes. Total thiamine concentrations in ova from Lake Winnipeg S. vitreus were approximately three times greater (mean 12 nmol g(-1) ) than in those from Lakes Erie or Ontario. The percentage of thiamine in the active form (thiamine pyrophosphate, TPP) was highest in Lake Ontario ova (mean 88%) and lowest in those from Lake Winnipeg (mean 70%). Neither ova total thiamine concentration nor per cent ova thiamine as TPP showed any consistent relationships with maternal age, size, morphometric condition, somatic lipid concentrations or liver lipid concentrations. Ova total thiamine concentration, however, was negatively related to ovum size in some populations, as well as among populations, and was positively related to liver total thiamine concentration. Maternal transfer of thiamine to ova appears to be independent of female ontogenetic or conditional state in S. vitreus.

A vegetation classification and description of white-winged flufftail (Sarothrura ayresi) habitat at selected high-altitude peatlands in South Africa.

The white-winged flufftail is listed as critically endangered, and limited knowledge about the species' ecology has been identified as a limiting factor to effectively conserving the bird. Little is known about the vegetation inhabited by the white-winged flufftail, which hampers the identification and management of its habitat. This study presents a fine-scale classification and description of the vegetation of wetland sites where the bird is known to be present. A plant phytosociological study was conducted to describe the plant communities and vegetation structure of the habitat. Three sites were selected at Verloren Valei Nature Reserve and two at Middelpunt Wetland, Mpumalanga, South Africa, shortly after the white-winged flufftail breeding season. A total of 60 sample plots were placed within the study sites, where all plant species present were recorded and identified. Other aspects such as plant height, water depth and anthropogenic influences were also documented. A modified TWINSPAN analysis resulted in the identification of three sub-communities that can be grouped into one major community. The Cyperaceae, Asteraceae and Poaceae families dominate the vegetation, with the sedges Carex austro-africana and Cyperus denudatus being dominant, and the grasses Leersia hexandra and Arundinella nepalensis co-dominant. The broad habitat structure consisted of medium to tall herbaceous plants (0.5-0.7 m) with shallow slow-flowing water.

Presentation of newly synthesized glycoproteins to CD4+ T lymphocytes. An analysis using influenza hemagglutinin transport mutants.

Human lymphoblastoid cells transiently expressing the hemagglutinin (HA) glycoprotein of influenza virus are rapidly and efficiently recognized by CD4+ HA-specific T lymphocytes. This endogenous presentation pathway is sensitive to chloroquine and is therefore likely related to the classical class II major histocompatibility complex (MHC) exogenous pathway of antigen presentation. In this study we have examined a series of transport-defective HA mutants. We correlate the intracellular fate of the native antigen with its presentation characteristics. We have found that the native antigen must enter the secretory pathway since a cytosolic form is not presented. However, surface expression and normal trafficking through the Golgi apparatus are not required for efficient presentation. Instead, escape of native antigen from the endoplasmic reticulum appears to be both necessary and sufficient for gaining access to a compartment where antigen is processed and binds class II MHC molecules.

Antibody recognition of an immunogenic influenza hemagglutinin-human leukocyte antigen class II complex.

The A/Japan/57 influenza hemagglutin (HA) peptide HA 128-145, when bound by human histocompatibility leukocyte antigen-DRw11 cells, is recognized by the human CD4+ T cell clone V1. A rabbit antiserum has been raised against HA 128-145 which recognizes not only the free peptide, but also the HA 128-145/DRw11 complex on a solid matrix, in solution, or on the surface of viable cells. The detection of these complexes on viable cells was shown to be class II specific, DRw11 restricted, and commensurate with the level of DRw11 expression. The identity of DRw11 as the cell surface molecule binding HA 128-145 was confirmed by immunoprecipitation, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and tryptic peptide mapping. Using this antiserum HA 128-145/DRw11 complexes could be detected on the cell surface as soon as 30 min after the peptide was added, and increased up to 24 h. Dissociation kinetics showed these complexes were long-lived, with a half-life of approximately 14 h. This anti-HA peptide antiserum represents the first direct means of studying antigenic peptide-human leukocyte antigen class II complexes on the surface of living cells without the addition of a non-amino acid moiety to the peptide. The properties of this antiserum thus provide the potential to study naturally processed antigenic peptides as well as the mechanism of processing itself in a physiologically relevant system.

Systematic review of online patient resources to support shared decision making for bariatric surgery.

BACKGROUND: Bariatric surgery is an effective treatment for obesity and the associated comorbidities but carries a number of important risks. The Royal College of Surgeons advises patients to utilise online resources as part of the shared decision-making process. The aim of this study was to assess the quality of online materials on bariatric surgery. METHODS: A systematic review was performed of online healthcare information relating to bariatric surgery. Common search terms were entered into three main search engines according to a defined search strategy. Websites were assessed according to readability (Flesch-Kincaid Reading Ease Score), quality and content (DISCERN and IPDAS Scores) and standards of accreditation (HONcode and Information Standard Certification). This systematic review was registered on the PROSPERO database CRD42019132188. RESULTS: The average readability of all sources extracted was higher than that recommended for patient literature. Over half the studies contained had received HONcode or Information Standard accreditation, suggesting a quality marker for the content. On grading of quality and content, across validated scoring tools, no source achieved the minimum recommended level. CONCLUSION: Patient information online related to bariatric surgery is of poor quality. Such resources require improvement to aid in the shared decision-making process.

The world outlook for conventional agriculture. More emphasis is needed on farm price policy and plant research if future world food needs are to be met.

1) The worldwide demand for food will continue to be strong in the coming decades. Two forces-rapidly growing population and, in much of the world, rapidly rising incomes-are expected to result in increases in the demand for food even more rapid than those that have occurred during the past. 2) Conventional agriculture has assured an adequate food supply for the economically advanced one-third of the world. The challenge now is to assure an adequate food supply for the remaining two-thirds, where population is now increasing at the rate of 1 million people per week and where malnutrition is already widespread. 3) Economically feasible prospects for significantly expanding the world's area of cultivated land in the 1960's and 1970's are limited and largely confined to sub-Saharan Africa and the Amazon Basin. Even here, agronomic problems will limit the rate of expansion. When the cost of desalting seawater is substantially reduced-probably not before the late 1970's or early 1980's at best-it may become feasible to irrigate large areas of desert. 4) Given the limited possibilities for expanding the area of land under cultivation, most of the increases in world food needs must be met, for the foreseeable future, by raising the productivity of land already under cultivation. Food output per acre, rather static throughout most of history, has begun to increase rapidly in some of the more advanced countries in recent decades. All of the increases in food production over the past quarter century in North America, western Europe, and Japan have come from increasing the productivity of land already under cultivation. The area under cultivation has actually declined. 5) Achieving dramatic gains in land productivity requires a massive investment of capital and the widespread adoption of new technology. A similar effort must now be made in the less-developed nations if these nations are to feed their people. The most important single factor influencing this rate of investment is food prices, more particularly the relationship between the price farmers receive for their food products and the cost of modern inputs such as fertilizer. 6) In some of the more-developed countries where per-acre yields have been rising for a long time, there is now evidence that the rate of yield increase may be slowing. Nonrecurring inputs may have made their maximum contribution to output in the case of some crops, pushing yield levels past the middle of the S-shaped logistic curve. Although this cannot be determined with any certainty, the possibility that the middle of the curve has been passed in some instances should be taken into account in viewing the long-term future. 7) If the rate of increase in yield per acre does in fact begin to slow in some of the agriculturally advanced countries, additional pressure will be put on the less-developed countries-which have much of the world's unrealized food-production potential-to meet the continuing future increases in world food needs. 8) Man has not yet been able to bypass the process of photosynthesis in the production of food. This dependence on photosynthesis plays a significant role in determining the upper levels of the S-shaped yield curve. Additional research is urgently needed to increase the photosynthetic efficiency of crops and to raise the upper levels of economically feasible yields.

Vaccination--knowledge and attitudes of school children.

Low vaccine up-take in Ireland resulted in the measles epidemic of 2000-2001, and more recent outbreaks of mumps in many schools and colleges. Forty-five schools were selected from a list of secondary schools in Ireland using a table of random numbers, and teachers were requested to distribute self-administered questionnaires to their 4th year students. The questionnaires were analysed using Epi-Info and chi-square test. 86% (n=675) of students considered themselves inadequately informed about vaccines and vaccine-preventable diseases. 67.9% (n=532) wanted the topic added to the science syllabus. 88.3% (n=692) agreed that they would vaccinate their own children against all childhood diseases. It is recommended that the topic of vaccination be covered more completely by the Junior Certificate Science syllabus. It is concluded that the vaccination up-take rates in the Ireland should rise with the next generation.

Perforated diverticulitis in the North of England: trends in patient outcomes, management approach and the influence of subspecialisation.

INTRODUCTION: In recent years, several management options have been used in the management of perforated diverticulitis, ranging from conservative treatment to laparotomy. General surgery has also become increasingly specialised over time. This retrospective cohort study investigated changes in patient outcomes following perforated diverticulitis, management approach and the influence of consultant subspecialisation over time. MATERIALS AND METHODS: Data was collected on patients admitted with perforated diverticulitis in the North of England between 2002 and 2016. Subspecialisation was categorised as colorectal or other general subspecialties. The primary outcome of interest was overall 30-day mortality; secondary outcomes included surgical approach, stoma and anastomosis rate. RESULTS: A total of 3394 cases of perforated diverticulitis were analysed (colorectal, n = 1290 and other subspecialists, n = 2104) with a 30-day mortality of 11.6%. There was a significant reduction in mortality over time (2002-2006: 18.6% to 2012-2016: 6.8, P < 0.001).There was a significant reduction in open surgery (60% to 25.3%, P < 0.001) with increased conservative management (37.4% to 63.5%, P < 0.001), laparoscopic resection (0.1% to 4.9%, P < 0.001) and laparoscopic washout (0.1% to 5.7%, P < 0.001).Patients admitted under colorectal surgeons had lower mortality than other subspecialists (9.9% vs 12.4%, P = 0.027), which remained significant following multivariate adjustment (hazard ratio 1.44, P = 0.039). These patients had fewer stomas (13.9% vs. 21.0%, P = 0.001) and higher anastomosis rates (22.1% vs 15.8%, P = 0.004). CONCLUSION: This study demonstrated considerable improvements in the management of perforated diverticulitis alongside the positive impact of subspecialisation on patient outcomes.

Direct identification of NH...N hydrogen bonds in non-canonical base pairs of RNA by NMR spectroscopy.

It is shown that the recently developed quantitative J(NN)HNN-COSY experiment can be used for the direct identification of hydrogen bonds in non-canonical base pairs in RNA. Scalar(2h)J(NN)couplings across NH.N hydrogen bonds are observed in imino hydrogen bonded GA base pairs of the hpGA RNA molecule, which contains a tandem GA mismatch, and in the reverse Hoogsteen AU base pairs of the E-loop of Escherichia coli 5S rRNA. These scalar couplings correlate the imino donor(15)N nucleus of guanine or uridine with the acceptor N1 or N7 nucleus of adenine. The values of the corresponding(2h)J(NN)coupling constants are similar in size to those observed in Watson-Crick base pairs. The reverse Hoogsteen base pairs could be directly detected for the E-loop of E.coli 5S rRNA both in the free form and in a complex with the ribosomal protein L25. This supports the notion that the E-loop is a pre-folded RNA recognition site that is not subject to significant induced conformational changes. Since Watson-Crick GC and AU base pairs are also readily detected the HNN-COSY experiment provides a useful and sensitive tool for the rapid identification of RNA secondary structure elements.

Use of fully deuterated micelles for conformational studies of membrane proteins by high resolution 1H nuclear magnetic resonance.

Micellar complexes of melittin with fully deuterated detergents have been studied by high resolution 1H nuclear magnetic resonance (NMR). The synthesis of deuterated micelles is described and it is shown that the 1H NMR spectrum of micelle-bound melittin is well resolved and suitable for detailed analysis by conventional high-resolution NMR methods. A preliminary characterization of micelle-bound melittin shows that interaction with the micelle results in different conformational and dynamic features for the hydrophobic and hydrophilic regions of the melittin amino acid sequence. The present experiments on melittin and preliminary results with other polypeptides and proteins demonstrate that in favourable cases high-resolution 1H NMR studies of the complexes formed between membrane proteins and deuterated micelles provides a viable method for conformational studies of membrane-bound proteins.

A spin label study of lipid oxidation catalyzed by heme proteins.

Rapid loss of the electron spin resonance signal from a variety of spin labels is observed when ferricytochrome c or metmyoglobin are combined with lipids. Evidence is presented that this loss of signal can be used as a sensitive method to study lipid oxidation catalyzed by heme proteins. Under aerobic conditions and with lipids which bind the heme protein, the kinetics of the oxidation process as observed by the spin label method are identical to the kinetics previously observed by measurements of oxygen uptake. Use of pre-oxidized lipids under anaerobic conditions indicates that cytochrome c reacts with a product of lipid oxidation. Kinetic studies of the anaerobic reaction indicate that cytochrome c reacts rapidly with lipid oxidation products in membrane areas far larger than the area occupied by cytochrome c, implying rapid transport of reactive species within the membrane interior in directions parallel to the membrane surface. Under anaerobic conditions, reaction of cytochrome c with lipid oxidation products appears to produce a relatively long lived (hours) species located in the hydrophobic portion of the membrane, which is capable of subsequent reaction with lipid-soluble spin labels.