Hemicellulose-Cellulose Composites Reveal Differences in Cellulose Organization after Dilute Acid Pretreatment

Model hemicellulose-cellulose composites that mimic plant cell wall polymer interactions were prepared by synthesizing deuterated bacterial cellulose in the presence of glucomannan or xyloglucan. Dilute acid pretreatment (DAP) of these materials was studied using small-angle neutron scattering, X-ray diffraction, and sum frequency generation spectroscopy. The macrofibril dimensions of the pretreated cellulose alone were smaller but with similar entanglement of macrofibrillar network as native cellulose. In addition, the crystallite size dimension along the (010) plane increased. Glucomannan-cellulose underwent similar changes to cellulose, except that the macrofibrillar network was more entangled after DAP. Conversely, in xyloglucan-cellulose the macrofibril dimensions and macrofibrillar network were relatively unchanged after pretreatment, but the cellulose I_β content was increased. Our results point to a tight interaction of xyloglucan with microfibrils while glucomannan only interacts with macrofibril surfaces. This study provides insight into roles of different hemicellulose-cellulose interactions and may help in improving pretreatment processes or engineering plants with decreased recalcitrance.

Precision lattice parameter determination from transmission diffraction of thick specimens with irregular cross sections

Accurate determination of lattice parameters from X-ray diffraction requires that the diffraction angles be measured very precisely, and significant errors result if the sample–detector separation differs from that assumed. Transmission diffraction from bones, which have a complex cross section and must be left intact, is a situation where this separation is difficult to measure and it may differ from position to position across the specimen. This article describes a method for eliminating the effect of variable sample cross section. Diffraction patterns for each position on the specimen are collected before and after 180° rotation about an axis normal to the cross section of interest. This places the centroid of the diffracting mass at the center of rotation and provides the absolute lattice parameters from the average apparent lattice parameters at the two rotation angles. Diffraction patterns were collected across the cross section of three specimens: a 3D-printed elliptical cylinder of Hyperelastic Bone (HB), which is composed primarily of synthetic hydroxyapatite (hAp), a 3D-printed HB model of the second metacarpal bone (Mc2), and a modern human Mc2 containing nanocrystalline carbonated apatite (cAp). Rietveld refinement was used to determine precise unit-cell parameters a apparent and c apparent for each pattern of each scan, and these values determined the actual average 〈a〉 and 〈c〉 for each sample. The results indicate that the 0°/180° rotation method works well enough to uncover variations approaching 1 × 10−3 Å in cAp unit-cell parameters in intact bones with irregular cross sections.

Outcomes of Endoscopic Sphincteroplasty Using Large Balloon Dilatation for Difficult Common Bile Duct Stone Removal at Dhulikhel Hospital

Background Endoscopic sphincteroplasty (ESPT) using a large Controlled Radial Expansion (CRE) Wire guided balloon dilatation has gained acceptance in removing a difficult common bile duct (CBD) stones. Objective To evaluate effectiveness and complications of removing large and difficult bile duct stones with sphincterotomy combined with large balloon dilatation. Method A total of 132 patients, from February 2014 to June 2017, who had biliary ductal calculus which was either greater than 15 mm or difficult to remove with standard technique, underwent Endoscopic Retrograde Cholangiopancreaticography (ERCP) with Endoscopic sphincteroplasty using a large Controlled radial expansion wire guided balloon dilatation. The success rate of complete stone clearance and post Endoscopic Retrograde Cholangiopancreaticography complications were analyzed. Result There were 48 (36.4 %) male and 84 (63.6%) female patients with mean age of 55.48 ± 16.36 years. Stones were removed with sphincteroplasty in first attempt in 90 out of 132 (68.2%) patients, 26 out of 37 (70.27%) patients in second session and in all 7(100%) patients in third attempt. Five (11.90%) patients were lost to follow up and 4 were advised for surgery because of failure to remove stones by sphincteroplasty. Overall success of endoscopic sphincterotomy and large balloon dilatation in our study was 93.18%. Complications were seen in 17 (13.6%) patients; bleeding seen in 9 (6.8%) patients and mild pancreatitis in 8 (6.1%) patients. None of the patients had severe pancreatitis or perforation secondary to the procedure. Conclusion Endoscopic sphincteroplasty after sphincterotomy is an effective and safe technique for a difficult common bile duct stone removal.

Critical care usage after major gastrointestinal and liver surgery: a prospective, multicentre observational study

BACKGROUND

Patient selection for critical care admission must balance patient safety with optimal resource allocation. This study aimed to determine the relationship between critical care admission, and postoperative mortality after abdominal surgery.

METHODS

This prespecified secondary analysis of a multicentre, prospective, observational study included consecutive patients enrolled in the DISCOVER study from UK and Republic of Ireland undergoing major gastrointestinal and liver surgery between October and December 2014. The primary outcome was 30-day mortality. Multivariate logistic regression was used to explore associations between critical care admission (planned and unplanned) and mortality, and inter-centre variation in critical care admission after emergency laparotomy.

RESULTS

Of 4529 patients included, 37.8% (n=1713) underwent planned critical care admissions from theatre. Some 3.1% (n=86/2816) admitted to ward-level care subsequently underwent unplanned critical care admission. Overall 30-day mortality was 2.9% (n=133/4519), and the risk-adjusted association between 30-day mortality and critical care admission was higher in unplanned [odds ratio (OR): 8.65, 95% confidence interval (CI): 3.51-19.97) than planned admissions (OR: 2.32, 95% CI: 1.43-3.85). Some 26.7% of patients (n=1210/4529) underwent emergency laparotomies. After adjustment, 49.3% (95% CI: 46.8-51.9%, P<0.001) were predicted to have planned critical care admissions, with 7% (n=10/145) of centres outside the 95% CI.

CONCLUSIONS

After risk adjustment, no 30-day survival benefit was identified for either planned or unplanned postoperative admissions to critical care within this cohort. This likely represents appropriate admission of the highest-risk patients. Planned admissions in selected, intermediate-risk patients may present a strategy to mitigate the risk of unplanned admission. Substantial inter-centre variation exists in planned critical care admissions after emergency laparotomies.

A Randomized Study Comparing the Incidence of Postoperative Pain After Phrenic Nerve Infiltration Vs Nonphrenic Nerve Infiltration During Thoracotomy

Thoracotomy is a common surgical procedure performed worldwide for lung disease. Despite major advances in analgesia, patients still experience severe shoulder, central back and surgical incision site pain in the postoperative period. This study aimed to assess whether intraoperative phrenic nerve infiltration reduces the incidence of postoperative pain and improves peak flow volume measurements during incentive spirometry. 90 patients undergoing open lobectomy were randomly assigned to have phrenic nerve infiltration (n = 46) or not (n = 44). The phrenic nerve infiltration group received 10 mL of 0.25% bupivacaine into the periphrenic fat pad. Preoperative assessments of spirometry and pain scores were recorded (at rest and with movement). Postoperative assessments included peak flow and pain measurements at intervals up to 72 hours. Less shoulder pain was experienced with phrenic nerve infiltration up to 6 hours postsurgery at rest (P = 0.005) and up to 12 hours with movement (P < 0.001). Reduced back pain was reported in the phrenic nerve infiltration group up to 6 hours after surgery both at rest (P = 0.001) and with movement (P = 0.00). Phrenic nerve infiltration reduced pain at the incision site for up to 3 hours both at rest (P < 0.001) and with movement (P = 0.001). Spirometry readings dropped in both groups with consistently lower readings at baseline and follow-up in the PNI group (P = 0.007). Lower analgesic usage of patient controlled analgesia morphine (P < 0.0001), epipleural bupivacaine (P = 0.001), and oramorph/zomorph (P = 0.0002) were recorded. Our findings indicate that the use of phrenic nerve infiltration significantly reduced patient pain scores during the early postoperative period, particularly during movement. We believe that each technique has advantages and disadvantages; however, further studies with large sample size are warranted.

Pseudophakic mini-monovision: high patient satisfaction, reduced spectacle dependence, and low cost

BACKGROUND

Cataract surgery with pseudophakic mini-monovision has lower out-of-pocket patient expense than premium multifocal intraocular lenses (IOL). The purpose of this study was to evaluate patient-reported satisfaction and spectacle dependence for key activities of daily living after cataract surgery with pseudophakic mini-monovision. The study also examined statistical relationships between patient demographic variables, visual acuity and satisfaction.

METHODS

Prospective cohort study of 56 patients (112 eyes) who underwent bilateral cataract surgery with pseudophakic mini-monovision. Mini-monovision corrects one eye for distance vision and the other eye is focused at near with - 0.75 to - 1.75 D of myopia. All patients with 1 diopter or greater of corneal astigmatism had a monofocal toric IOLs implanted or limbal relaxing incision. The main study outcomes were assessed at the last follow-up appointment and included refraction, visual acuity, patient reported spectacle use, and patient satisfaction. Descriptive statistics, correlation matrixes and Pearson's chi-square tests were examined.

RESULTS

Uncorrected visual acuity was significantly better post-operatively. Most patients reported the surgery met their expectations for decreased dependence on spectacles (93%). Most patients report little or no use of spectacles post-operatively for computer use (93%), distance viewing (93%) and general use throughout the day (87%). A small number of patients report spectacle use for reading (9%) and night driving (18%). There were no relationships detected between demographic variables and visual acuity or patient satisfaction.

CONCLUSIONS

Aging of the population presents one of the biggest challenges in the health sector, which includes a rising number of individuals with chronic vision impairment and increased demand for accessible treatment strategies. Cataract surgery with pseudophakic mini-monovision results in high patient satisfaction and considerable reduction in spectacle dependence. Pseudophakic mini-monovision technique is a low-cost, valuable option for patients who would like to reduce dependence on spectacles post-operatively and should be considered along with premium multifocal IOLs in options available for patients based on their needs, preferences and clinical indicators. Reducing spectacle dependence with the pseudophakic mini-monovision technique could improve the functionality, independence and quality of life for many patients who are unsuitable or are unable to pay additional fees associated with premium multifocal IOLs.

Zonal cortical scarring and tubular thyroidization in kidney biopsies of patients with SLE-histologic indicator for antiphospholipid antibodies

Antiphospholipid antibody syndrome (APS) is an acquired prothrombotic autoimmune disease caused by the presence of antibodies against anionic phospholipids or plasma proteins bound to phospholipids on cell membranes. It can be a primary disease or secondary to other autoimmune diseases, most commonly systemic lupus erythematosus (SLE). Laboratory testing for antiphospholipid antibodies (aPL) may be only transiently positive, so APS could be missed until a catastrophic thrombotic episode or pregnancy morbidity occurs. In the kidneys, this manifests as thrombotic microangiopathy (TMA), and patients present with hypertensive urgency and acute kidney injury. However, APS may not always have a catastrophic presentation but instead a more smoldering course. Kidney biopsy may not show obvious active TMA lesions but rather only chronic injury in the form of zonal cortical scarring and tubular thyroidization. Still, it may warrant anticoagulation therapy. So it is important to recognize this pattern of injury in the biopsy. Herein, we retrospectively study the correlation between presence of this histologic feature in kidney biopsies of SLE patients and positive aPL testing results (anticardiolipin antibodies and/or lupus anticoagulant). Kidney biopsies of SLE patients from 2004 to 2015 ( n = 186) were screened for presence or absence of zonal cortical scarring. Their electronic medical records were reviewed for aPL results. Our study showed low sensitivity (33%) but higher positive predictive value (62%), specificity (89%) and negative predictive value (71%). This histologic finding is therefore not a sensitive screening tool, but if present, greatly increases the likelihood of underlying aPL. We want to emphasize that recognition of this histologic feature in the biopsies of SLE patients is important so as not to miss the opportunity to treat with anticoagulation therapy and possibly slow down the chronic renal damage.

Search for CP Violation in Neutrino and Antineutrino Oscillations by the T2K Experiment with 2.2×10^{21} Protons on Target

The T2K experiment measures muon neutrino disappearance and electron neutrino appearance in accelerator-produced neutrino and antineutrino beams. With an exposure of 14.7(7.6)×10^{20} protons on target in the neutrino (antineutrino) mode, 89 ν_{e} candidates and seven anti-ν_{e} candidates are observed, while 67.5 and 9.0 are expected for δ_{CP}=0 and normal mass ordering. The obtained 2σ confidence interval for the CP-violating phase, δ_{CP}, does not include the CP-conserving cases (δ_{CP}=0, π). The best-fit values of other parameters are sin^{2}θ_{23}=0.526_{-0.036}^{+0.032} and Δm_{32}^{2}=2.463_{-0.070}^{+0.071}×10^{-3}  eV^{2}/c^{4}.

Effects of Inadequate Sleep on Blood Pressure and Endothelial Inflammation in Women: Findings From the American Heart Association Go Red for Women Strategically Focused Research Network

BACKGROUND

Insufficient sleep increases blood pressure. However, the effects of milder, highly prevalent but frequently neglected sleep disturbances, including poor sleep quality and insomnia, on vascular health in women are unclear. We investigated whether poor sleep patterns are associated with blood pressure and endothelial inflammation in a diverse sample of women.

METHODS AND RESULTS

Women who participated in the ongoing American Heart Association Go Red for Women Strategically Focused Research Network were studied (n=323, 57% minority, mean age=39±17 years, range=20-79 years). Sleep duration, sleep quality, and time to sleep onset were assessed using the Pittsburgh Sleep Quality Index (score ≥5=poor sleep quality). Risk for obstructive sleep apnea was evaluated using the Berlin questionnaire, and insomnia was assessed using the Insomnia Severity Index. In a subset of women who participated in the basic study (n=26), sleep duration was assessed objectively using actigraphy, and endothelial inflammation was assessed directly in harvested endothelial cells by measuring nuclear translocation of nuclear factor kappa B. Vascular reactivity was measured by brachial artery flow-mediated dilation (n=26). Systolic and diastolic blood pressure were measured by trained personnel (n=323). Multivariable linear regressions were used to evaluate associations between sleep patterns and blood pressure, nuclear factor kappa B, and flow-mediated dilation. Mean sleep duration was 6.8±1.3 hours/night in the population study and 7.5±1.1 hour/night in the basic study. In the population study sample, 50% had poor sleep quality versus 23% in the basic study, and 37% had some level of insomnia versus 15% in the basic study. Systolic blood pressure was associated directly with poor sleep quality, and diastolic blood pressure was of borderline significance with obstructive sleep apnea risk after adjusting for confounders (P=0.04 and P=0.08, respectively). Poor sleep quality was associated with endothelial nuclear factor kappa B activation (β=30.6; P=0.03). Insomnia and longer sleep onset latency were also associated with endothelial nuclear factor kappa B activation (β=27.6; P=0.002 and β=8.26; P=0.02, respectively). No evidence was found for an association between sleep and flow-mediated dilation.

CONCLUSIONS

These findings provide direct evidence that common but frequently neglected sleep disturbances such as poor sleep quality and insomnia are associated with increased blood pressure and vascular inflammation even in the absence of inadequate sleep duration in women.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT02835261.

Characterization of genetic changes associated with daptomycin nonsusceptibility in Staphylococcus aureus

The extensive use of daptomycin (DAP) for treatment of methicillin-resistant Staphylococcus aureus (MRSA) infections in the last decade has led to the emergence of DAP non-susceptible (DNS) Staphylococcus aureus strains. A better understanding of the molecular changes underlying DAP-non-susceptibility is required for early diagnosis and intervention with alternate combination therapies. The phenotypic changes associated with DNS strains have been well established. However, the genotypic changes—especially the kinetics of expression of the genes responsible for DAP-non-susceptibility are not well understood. In this study, we used three clinically derived isogenic pairs of DAP-susceptible (DAP-S) and DNS S. aureus strains to study gene expression profiles with the objective of identifying the potential genotypic changes associated with DAP-nonsusceptibility. We determined the expression profiles of genes involved in cell membrane (CM) charge, autolysis, cell wall (CW) synthesis, and penicillin binding proteins in DAP-S and DNS isogenic pairs. Our results demonstrate characteristic expression profiles for mprF, dltABCD, vraS, femB, and pbp2a genes, which are common to all the DNS S. aureus strains tested. Whole genome sequencing of DAP-S and DNS clinical isolates of S. aureus showed non-synonymous mutations in all DNS strains in genes involved in CM charge, CM composition, CW thickness and CW composition. To conclude, this study unravels some of the complex molecular changes involved in the development of DAP-nonsusceptibility by demonstrating distinct differences in gene expression profiles and mutations in the DNS S. aureus strains. This knowledge will aid in rapid identification of DNS S. aureus in clinical settings.

Mad2 Overexpression Uncovers a Critical Role for TRIP13 in Mitotic Exit

The mitotic checkpoint ensures proper segregation of chromosomes by delaying anaphase until all kinetochores are bound to microtubules. This inhibitory signal is composed of a complex containing Mad2, which inhibits anaphase progression. The complex can be disassembled by p31^comet and TRIP13; however, TRIP13 knockdown has been shown to cause only a mild mitotic delay. Overexpression of checkpoint genes, as well as TRIP13, is correlated with chromosomal instability (CIN) in cancer, but the initial effects of Mad2 overexpression are prolonged mitosis and decreased proliferation. Here, we show that TRIP13 overexpression significantly reduced, and TRIP13 reduction significantly exacerbated, the mitotic delay associated with Mad2 overexpression, but not that induced by microtubule depolymerization. The combination of Mad2 overexpression and TRIP13 loss reduced the ability of checkpoint complexes to disassemble and significantly inhibited the proliferation of cells in culture and tumor xenografts. These results identify an unexpected dependency on TRIP13 in cells overexpressing Mad2.

Abstract P6-08-05: United States real-world drug utilization patterns and associated overall survival in Medicare patients with newly-diagnosed metastatic triple negative breast cancer using surveillance, epidemiology, and end results-Medicare data

Background: Limited information is available about treatment patterns for elderly patients (pts) with metastatic triple negative breast cancer (mTNBC). This analysis characterized real-world drug utilization patterns and associated overall survival (OS) for Medicare mTNBC pts.

Methods: Pts ≥66 years of age who were newly diagnosed with mTNBC between 2004 and 2011 were identified from the Surveillance, Epidemiology, and End Results (SEER)-Medicare linked database. Triple negative status was obtained from the SEER registry, except for HER2 that was unavailable from 2004-2009 during which we assumed that pts who had a claim for a HER2 test followed by absence of hormonal therapy to be presumed HER2 negative. Pts were followed from diagnosis to death, Medicare disenrollment, HMO enrollment, or 12/31/2013 (whichever occurred first) to characterize the sequence of chemotherapy received – first regimen (1R), second regimen (2R), and third regimen (3R) and median (interquartile, IQR) duration of and between regimens. OS estimates were reported using the Kaplan-Meier method.

Results: Among 694 mTNBC pts, 69 died within 30 days of diagnosis and were excluded. In the remaining 625 pts observed from 2004 through 2013 (median age: 75 years; Charlson comorbidity index (CCI) ≥2: 21%; and median follow-up: 11.4 months), 317 (51%) received chemotherapy. Of the 317 pts, 161 got only 1R, 88 got only 2R, and 68 got 3R+. Compared to pts on 1R, pts on 2R were significantly younger (median age: 2R, 72; 1R, 75 years), married (2R, 40%; 1R, 30%), had fewer comorbidities (CCI≥2: 2R, 16%; 1R, 23%). The top 2 most commonly prescribed single agents in 1R, 2R, and 3R were: 1R, paclitaxel followed by capecitabine; 2R, capecitabine followed by paclitaxel; 3R, gemcitabine followed by capecitabine. The most common combination regimen given was taxane-based in 1R (57%) and 2R (70%).

Drug utilization patterns First Regimen (n=317)Second Regimen (n=156)Third Regimen (n=68)Single Agent205 (65%)74 (47%)40 (59%)Microtubule inhibitors80 (39%)23 (31%)NRPaclitaxel72 (35%)18 (24%)NRAnthracyclines29 (14%)13 (18%)NRDoxorubicin27 (13%)13 (18%)NRAntimetabolites/Others96 (47%)38 (51%)27 (73%)Capecitabine51 (25%)20 (27%)NRGemcitabineNRNR13 (35%)OthersNRNRNRCombination Regimens112 (35%)82 (53%)28 (41%)Taxane-based64 (57%)57 (70%)NRNR, not reported per DUA with NCI. %, col. % relative to single/comb. category

Median (IQR) durations of 1R, 2R, and 3R were 2.7 (1.4-4.4), 3.1 (1.6-5.0), and 2.3 (0.9-4.5) months, respectively. Median time from diagnosis to start of 1R was 1.6 (0.9-2.8) months. Median time to start of 2R and 3R after the end of the previous regimen was 4.6 (2.1-8.1), and 6.2 (3.3-11.0) months, respectively. The median (12-month) OS was 7 months (34%) for all pts and ranged from 3.5 (17%) in the untreated to 25.3 (88%) months in 3R+ pts.

Conclusions: About half of Medicare mTNBC pts do not receive chemotherapy in the real world. Paclitaxel and capecitabine were the most commonly used single agents and taxane-based combination therapy was the most commonly used combination.

Citation Format: Aly A, Shah R, Hill K, Waldeck AR, Botteman M. United States real-world drug utilization patterns and associated overall survival in Medicare patients with newly-diagnosed metastatic triple negative breast cancer using surveillance, epidemiology, and end results-Medicare data [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-08-05.