Early diagnosis of acute myocardial infarction in patients with a history of percutaneous coronary intervention

Background

Recurrence of acute chest pain after percutaneous coronary intervention (PCI) is common. The early detection of acute myocardial infarction (AMI) as a possible cause of acute chest pain can be challenging in patients with a history of PCI due to e.g. pre-existing electrocardiographic abnormalities. It is unknown, whether high-sensitivity cardiac troponin T (hs-cTnT) concentrations and hs-cTnT-based rapid algorithms perform equally well in patients with a history of PCI.

Purpose

To investigate the impact of prior PCI on the diagnostic performance of hs-cTnT concentrations for early rule-out and rule-in of AMI.

Methods

In an ongoing multicentre international study, we prospectively enrolled unselected patients presenting to the emergency department (ED) with symptoms suggestive of AMI. Final diagnoses were centrally adjudicated by two independent cardiologists using all available medical records obtained during clinical care including 90 day follow-up information and cardiac imaging. High-sensitivity cTnT concentrations at presentation and after 1h were compared against the adjudicated final diagnosis. Patients were stratified according to the presence or absence of previous PCI.

Results

Among 5536 patients (1313 with and 4223 without previous PCI), incidence of AMI was significantly higher in patients with previous PCI (26.3% versus 21.4%; p<0.001). Patients with prior PCI and a final diagnoses other than AMI had significantly higher concentrations of hs-cTnT at presentation to the ED (median 9ng/l [IQR 6 to 15.8] vs 5.5ng/l [IQR 3 to 10]; p<0.001). However, in patients with final adjudicated diagnosis of AMI, hs-TnT concentrations at presentation were lower in patients with previous PCI (median 46ng/l [IQR 23 to 94] vs 55ng/l [IQR 25 to 175]; p=0.003). The diagnostic accuracy of hs-cTnT was high in patients with history of PCI, but significantly lower compared to patients without PCI (AUC 0.91 [95% CI 0.89–0.92] versus AUC 0.94 [95% CI 0.94–0.95]; p<0.001, respectively). When applying the ESC 0/1-algorithm among patients with previous history of PCI, the rule out pathway showed also very high safety in patients with a history of PCI (sensitivity 99.2 [95% CI 97.2–99.8] and negative predictive value 99.6 [95% CI 98.5–99.9]). However, the efficacy of the ESC 0/1h-algorithm for early rule out of NSTEMI was lower in the PCI group compared to no PCI (45.2% vs 65.1%; P<0.001, respectively), triaging more patients to the observe zone (36.8% versus 18.8%; p<0.001). Time to discharge from the ED was significantly longer in patients with prior PCI (334 min vs 290 min; p<0.001). When stratified for index AMI, patients with history of PCI waited longer for a final diagnoses of AMI (285 vs 217 min; p<0.001).

Conclusions

History of PCI impacts on the diagnostic performance of hs-cTnT. Although the ESC 0/1h-algorithm still performs very safe when applied to patients with a history of PCI, its efficacy is significantly reduced.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Swiss National Science Foundation, the Swiss Heart Foundation, the KTI, the Stiftung für kardiovaskuläre Forschung Basel the University of Basel and the University Hospital Basel

Incidence, characteristics and prognosis of different cardiac etiologies underlying cardiac syncope

Background

Cardiac syncope has been shown to carry the highest hazard for all-cause death compared to other causes of syncope including vasovagal and orthostatic syncope. However, little is known about the incidence, characteristics and prognosis of different cardiac etiologies underlying cardiac syncope.

Purpose

To evaluate the incidence, characteristics and prognosis of different cardiac etiologies underlying cardiac syncope.

Methods

We enrolled patients presenting to the emergency department (ED) with syncope in a large prospective international multicentre study. The cause of syncope (cardiac vs non-cardiac) including the detailed cardiac aetiology (if cardiac) was centrally adjudicated by two independent cardiologists based on detailed in-hospital as well as outpatient cardiac work-up during 360 days following presentation. Cardiac syncope was classified into four groups: bradyarrhythmia, tachyarrhythmia, structural disease and other (cardiopulmonary and great vessels), as recommended in the ESC Syncope Guidelines. All-cause death during 2-years follow-up was the primary outcome.

Results

Among 2025 patients presenting with syncope to the ED, cardiac syncope was the final adjudicated diagnoses in 318 (15.7%) patients. The incidence rate of all-cause death among cardiac syncope patients was 103 cases per 1000 person-years. Bradyarrhythmia was the most frequent primary cause of cardiac syncope (n=146, 45.9%) followed by tachyarrhythmia (n=75, 23.6%), structural disease (n=64, 20.1%) and other cardiac (n=26, 8.2%). Patients were 37% female with a median age of 77 years (IQR 67–83) showing no statistically significant difference between subgroups. Clinical characteristics differed significantly among the four subgroups. E.g. syncope occurred during exercise in 12 patients (8.2%) with bradyarrhythmia, 10 patients (13.3%) with tachyarrhythmia, 16 patients (25%) with structural disease, and 5 patients (19%) with other cardiac (p<0.01). Likely of most importance, long-term mortality differed significantly among the four different cardiac subgroups. The multivariable-adjusted hazard ratios (HR) among patients with bradyarrhythmia, tachyarrhythmia, structural disease and other cardiac as compared to patients with vasovagal syncope, the HR were 1.3 (95% CI 0.7–2.5), 4.6 (95% CI 2.3–9.1), 3.1 (95% CI 1.5–6.4) and 5.9 (95% CI 2.3–15.2), respectively (Figure 1).

Conclusions

Bradyarrhythmia, tachyarrhythmia, and structural cardiac disease are the dominant causes of cardiac syncope. Interestingly, with the appropriate therapy initiated long-term mortality of bradyarrhythmia is comparable to that of vasovagal syncope, while long-term mortality of tachyarrhythmia and structural cardiac disease were substantially increased 3 to 5 fold.

Figure 1. Kaplan-Meier curve

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): The Swiss National Science Foundation, the Swiss Heart Foundation, the Stiftung für kardiovaskuläre Forschung Basel, the University of Basel and the University Hospital Basel.

External validation of a clinical decision rule to identify patients at low risk for acute coronary syndrome who do not need objective coronary artery disease testing

Background

Rapid high-sensitivity cardiac troponin (hs-cTn) based algorithms have substantially improved the early rule-out of acute myocardial infarction (AMI) and thereby facilitated the selection of patients eligible for outpatient management. However, it remains unclear, which patients after rule-out of AMI should still undergo objective anatomic or functional cardiac testing for the detection of relevant coronary artery disease. A pilot study has derived a clinical decision rule for the selection of patients who do not need objective anatomic or functional cardiac testing for coronary artery disease (“No Objective Testing” (NOT) rule).

Purpose

To externally validate the performance of the NOT-rule in a multicentre study.

Methods

Patients presenting to the ED with symptoms suggestive of an acute coronary syndrome (ACS) were enrolled in a large prospective international multicentre study at 12 study sites in five European countries. Two independent cardiologists centrally adjudicated the final diagnosis using all clinical data including cardiac imaging and at least 90-day follow-up. The NOT-rule is applied in patients, in whom a 2h accelerated diagnostic protocol (using hs-cTnI concentrations at 0h/2h and ECG data) has ruled-out AMI and based on clinical variables. In brief, the first rule is a weighted score derived from independent predictors of ACS that classifies patients as low-risk if they score ≤4 points. The second rule was simplified and ruled patients out if they were younger than 50 years, had no history of an AMI or known CAD, and no prescribed nitrates. The third rule equals the second except nitrate use was omitted. Primary objective was the safety and efficacy of the NOT-rules for rule-out of major adverse cardiac events (MACE) including AMI, unstable angina pectoris, urgent or emergency revascularisation or cardiovascular death at 30-days of follow-up. Secondary objective was the safety and efficacy for rule-out of MACE at 2-years.

Results

Out of 3188 enrolled patients, 2162 (68%) had hs-cTnI concentrations at 0h and 2h below the 99th centile as well as a non-diagnostic ECG and were therefore eligible for the analysis. MACE at 30-days occurred in 302 (14%) patients. The second and third rule offered highest safety and efficacy for rule-out of MACE at 30-days. Both identified 492 (23%) patients at low-risk with a sensitivity of 99.7% (95% CI 98.2–99.9%) and a negative predictive value (NPV) of 99.8% (95% CI 98.6–99.9%). One MACE was missed within 30-days (revascularisation of a one-vessel CAD). Sensitivity 98.9% (95% CI 97.1–99.7%) and NPV 99.2% (95% CI 97.8–99.7) were also very high for 1-year MACE, as well as 2-year MACE 98.4% (95% CI 96.5–99.4%) and 98.4% (95% CI 96.5–99.3%), respectively.

Conclusions

The NOT rules proved to be a safe tool that identifies nearly one-fourth of patients at very low risk for MACE, who may not need objective anatomic or functional cardiac testing for coronary artery disease.

Performance of NOT rules

Funding Acknowledgement

Type of funding source: Other. Main funding source(s): Swiss National Science Foundation, the Swiss Heart Foundation, the KTI, the European Union, the Stiftung für kardiovaskuläre Forschung Basel, the University of Basel, the University Hospital Basel

Radiomics of MRI for pretreatment prediction of pathologic complete response, tumor regression grade, and neoadjuvant rectal score in patients with locally advanced rectal cancer undergoing neoadjuvant chemoradiation: an international multicenter study

OBJECTIVE

To investigate whether pretreatment MRI-based radiomics of locally advanced rectal cancer (LARC) and/or the surrounding mesorectal compartment (MC) can predict pathologic complete response (pCR), neoadjuvant rectal (NAR) score, and tumor regression grade (TRG).

METHODS

One hundred thirty-two consecutive patients with LARC who underwent neoadjuvant chemoradiation and total mesorectal excision (TME) were retrospectively collected from 2 centers in the USA and Italy. The primary tumor and surrounding MC were segmented on the best available T2-weighted sequence (axial, coronal, or sagittal). Three thousand one hundred ninety radiomic features were extracted using a python package. The most salient radiomic features as well as MRI parameter and clinical-based features were selected using recursive feature elimination. A logistic regression classifier was built to distinguish between any 2 binned categories in the considered endpoints: pCR, NAR, and TRG. Repeated k-fold validation was performed and AUCs calculated.

RESULTS

There were 24, 87, and 21 T4, T3, and T2 LARCs, respectively (median age 63 years, 32 to 86). For NAR and TRG, the best classification performance was obtained using both the tumor and MC segmentations. The AUCs for classifying NAR 0 versus 2, pCR, and TRG 0/1 versus 2/3 were 0.66 (95% CI, 0.60-0.71), 0.80 (95% CI, 0.74-0.85), and 0.80 (95% CI, 0.77-0.82), respectively.

CONCLUSION

Radiomics of pretreatment MRIs can predict pCR, TRG, and NAR score in patients with LARC undergoing neoadjuvant treatment and TME with moderate accuracy despite extremely heterogenous image data. Both the tumor and MC contain important prognostic information.

KEY POINTS

• Machine learning of rectal cancer on images from the pretreatment MRI can predict important patient outcomes with moderate accuracy. • The tumor and the tissue around it both contain important prognostic information.

External validation of a suggested extension of the ESC 0/1h-algorithm for early rule out of myocardial infarction

Background

The European Society of Cardiology (ESC) high sensitivity cardiac troponin T 0/1h-algorithm has substantially improved the management of patients with suspected acute myocardial infarction (AMI) by triaging about 75% of patients to rapid rule-out and/or rapid rule-in. However, about 25% of patients remain in the “observe-zone”, and the optimal management of these patients is unknown. Recently, a pilot single center study with a low prevalence of AMI suggested that an absolute change of less than 7ng/L between the 0h and 3h hs-cTnT concentration would allow to help in the evaluation of patients in the observe-zone and allow triage towards rule-out with very high negative predictive value [NPV].

Purpose

To externally validate this suggested modification of the ESC 0/1h-algorithm for early rule out of AMI.

Methods

In an ongoing multicentre international study, we prospectively enrolled unselected patients presenting to the emergency department with symptoms suggestive of MI. Final diagnoses were centrally adjudicated by two independent cardiologists using all available medical records obtained during clinical care including 90 day follow-up information and cardiac imaging. High sensitivity-cTnT (Elecsys) concentrations were measured at presentation and after 1 and 3 hours. The primary outcome was safety, quantified by the sensitivity and NPV for early rule out of NSTEMI.

Results

Among 1633 enrolled patients with available 0, 1 and 3h hs-cTnT concentrations, NSTEMI was the adjudicated final diagnosis in 337 (20.6%) patients. The ESC 0/1h-algorithm ruled out 918 (56.2%) patients, with a sensitivity of 98.8% (95% confidence interval [CI], 97.0–99.5) and a NPV of 99.6% (95% CI, 98.9–99.8). A total of 428 patients (26.2%) remained in the observe zone. After applying the suggested 0–3 hour absolute change cut-off criteria of 7ng/L, 393 (92.0%) additional patients from the observe zone were triaged towards ruled out. However, the safety of this triage step was poor with 62 patients with NSTEMI missed, resulting in a sensitivity of 33.3% and a NPV of 84.2% for rule-out.

Conclusions

The suggested 0/3h absolute change cut-off of 7ng/L for patients remaining in the observe zone of the ESC 0/1h-algorithm does NOT allow safe rule-out of AMI and should therefore NOT be implemented into routine clinical care.

Figure 1

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Swiss National Science Foundation, the Swiss Heart Foundation, the Stiftung für kardiovaskuläre Forschung Basel, the University of Basel and the University Hospital Basel

Extraction of Beam-Spin Asymmetries from the Hard Exclusive π^{+} Channel off Protons in a Wide Range of Kinematics

We have measured beam-spin asymmetries to extract the sinϕ moment A_{LU}^{sinϕ} from the hard exclusive e[over →]p→e^{'}nπ^{+} reaction above the resonance region, for the first time with nearly full coverage from forward to backward angles in the center of mass. The A_{LU}^{sinϕ} moment has been measured up to 6.6  GeV^{2} in -t, covering the kinematic regimes of generalized parton distributions (GPD) and baryon-to-meson transition distribution amplitudes (TDA) at the same time. The experimental results in very forward kinematics demonstrate the sensitivity to chiral-odd and chiral-even GPDs. In very backward kinematics where the TDA framework is applicable, we found A_{LU}^{sinϕ} to be negative, while a sign change was observed near 90° in the center of mass. The unique results presented in this Letter will provide critical constraints to establish reaction mechanisms that can help to further develop the GPD and TDA frameworks.

Benchmarking of abdominal surgery: a study evaluating the HARM score in a European national cohort

Background

Reliable, easily accessible metrics of surgical quality are currently lacking. The HARM (HospitAl length of stay, Readmission and Mortality) score is a composite measure that has been validated across diverse surgical cohorts. The aim of this study was to validate the HARM score in a national population of patients undergoing abdominal surgery.

Methods

Data on all abdominal surgery in Norwegian hospitals from 2011 to 2017 were obtained from the Norwegian Patient Registry. Readmissions and 30‐day postoperative complications as well as deaths in and out of hospital were evaluated. The HARM scoring algorithm was tested after adjustment by establishing a newly proposed length of stay score. The correlation between the HARM score and complications, as well as the ability of aggregated HARM scores to discriminate between hospitals, were analysed. Risk adjustment models were developed for nationwide hospital comparisons.

Results

The data consisted of 407 113 primary operations on 295 999 patients in 85 hospitals. The HARM score was associated with complications and complication severity (Goodman–Kruskal γ value 0·59). Surgical specialty was the dominating variable for risk adjustment. Based on 1‐year data, the risk‐adjusted score classified 16 hospitals as low HARM score and 16 as high HARM score of the 53 hospitals that had at least 30 operations.

Conclusion

The HARM score correlates with major outcomes and is associated with the presence and severity of complications. After risk adjustment, the HARM score discriminated strongly between hospitals in a European population of abdominal surgery.

Survival of a probiotic-containing product using capsule-within-capsule technology in an in vitro model of the stomach and small intestine (TIM-1)

The aim of the research was to compare the survival of a blend of five probiotic strains (2 bifidobacteria and 3 lactobacilli) in a capsule within capsule (Duocap^®) containing Ahiflower^® oil, as compared to the strains in the powder (with or without Ahiflower oil), or the strains when present in the inner capsule only. This was tested in a validated, dynamic in vitro model of the stomach and small intestine (TIM-1), simulating human adults. Experiments were performed both in the gastric compartment of the model, as well as in the complete system (stomach + small intestine). Survival of the strains after transit through the gastric compartment in the Duocap capsule was higher by about a factor of 1.5 compared to the other 3 variables. In these gastric experiments, the Ahiflower oil did not seem to have an additional benefit, in the sense that it did not increase survival over the strains alone. After transit through the complete gastrointestinal tract survival was approximately 2-fold higher for the strains within the Duocap capsule, compared to the strains within the inner capsule or the powder. In these experiments, Ahiflower oil did have an additional benefit. The survival of the strains in the combination of powder with Ahiflower oil showed a similar survival as that of the Duocap, although in the first few hours of the experiments survival of both species lagged behind, and only caught up at the end of the test. In conclusion, the developed capsule-in-capsule technology increased the amount of viable cells in the upper gastrointestinal tract, mainly due to the presence of the polyunsaturated fatty acids contained in the outer capsule, which particularly protected the blend of probiotics in the small intestine.

Xylo-oligosaccharides from sugarcane show prebiotic potential in a dynamic computer-controlled in vitro model of the adult human large intestine

The aim of the study was to investigate the prebiotic potential of xylo-oligosaccharides (XOS) from sugarcane in a validated, dynamic, computer-controlled in vitro model of the colon (TIM-2) simulating human adults. In two sets of experiments, each with a different microbiota, 3 different doses of XOS were tested at 1.0 g/day, 1.5 g/day and 3.0 g/day. The in vitro model was run for 72 h, and at the start and subsequently every 24 h samples were taken and analysed for short-chain fatty acids (SCFA) and gut microbiota composition. SCFA were analysed using ion chromatography, whereas microbiota composition was analysed using sequencing of the V3-V4 region of the 16S rRNA gene. XOS showed a similar SCFA production per gram of substrate as the control medium, including butyrate, which is considered to be important for gut health. In both sets of experiments XOS showed a consistent dose-dependent increase in abundance over time of the genus Bifidobacterium, and within that of the species B. adolescentis and an unidentified species (labelled 'sp.1'). The results show the potential prebiotic effect of XOS from sugarcane, by its capacity to generate butyrate and increase the health-beneficial bifidobacteria.

Totally robotic vs hybrid abdominoperineal resection: A retrospective multicenter analysis

INTRODUCTION

Laparoscopic abdominoperineal resection (APR) for low rectal cancers is technically demanding. Robotic assistance may be of help and can be hybrid (HAPR) or totally robotic (RAPR). The present study describes outcomes of robotic APR and compares both approaches.

MATERIAL AND METHODS

A multicentric retrospective analysis of rectal cancer patients undergoing either HAPR or RAPR was conducted. Patients' demographics, surgeons' experience, oncologic results, and intraoperative and postoperative outcomes were collected.

RESULTS

One hundred twenty-five patients were included, 48 in HAPR group and 77 in RAPR group. Demographics and comorbidities were comparable. Operative time was reduced in RAPR group (266.9 ± 107.8 min vs 318.9 ± 75.1 min, P = .001). RAPR patients were discharged home more frequently (91.18% vs 66.67%, P = .001), and experienced fewer parastomal hernias (3.71% vs 9.86%, P = .001).

CONCLUSION

RAPR is safe and feasible with appropriate oncologic outcomes. Totally robotic approach reduces operative time and may improve functional outcomes.

Bacillus coagulans GBI-30, 6068 decreases upper respiratory and gastrointestinal tract symptoms in healthy Mexican scholar-aged children by modulating immune-related proteins

This randomized, double-blind, parallel and placebo-controlled study aimed to evaluate the effect of Bacillus coagulans GBI-30, 6086® probiotic (GanedenBC³⁰®) against upper respiratory tract infections (URTI) and gastrointestinal tract infections (GITI) in eighty healthy school-aged children (6-8 years old). The participants received daily a sachet containing either GanedenBC³⁰ (1 × 10⁹ colony-forming units) or placebo (maltodextrin) for three months. GanedenBC³⁰ significantly decreased the incidence of URTI symptoms including nasal congestion, bloody nasal mucus, itchy nose, and hoarseness. The duration of the URTI-associated symptoms of hoarseness, headache, red eyes, and fatigue was also decreased. GanedenBC³⁰ supplementation also significantly reduced the incidence rate of flatulence. These beneficial effects were associated with the modulation of serum TNFα, CD163, G-CSF, ICAM-1, IL-6, IL-8, MCP-2, RAGE, uPAR, and PF4. Therefore, probiotic B. coagulans GBI-30, 6086 modulated immune-related proteins in healthy children, decreasing several URTI and GITI symptoms, thus, this functional ingredient may contribute to a healthier lifestyle.

Exploring the Structure of the Bound Proton with Deeply Virtual Compton Scattering

In the past two decades, deeply virtual Compton scattering of electrons has been successfully used to advance our knowledge of the partonic structure of the free proton and investigate correlations between the transverse position and the longitudinal momentum of quarks inside the nucleon. Meanwhile, the structure of bound nucleons in nuclei has been studied in inclusive deep-inelastic lepton scattering experiments off nuclear targets, showing a significant difference in longitudinal momentum distribution of quarks inside the bound nucleon, known as the EMC effect. In this Letter, we report the first beam spin asymmetry (BSA) measurement of exclusive deeply virtual Compton scattering off a proton bound in ^{4}He. The data used here were accumulated using a 6 GeV longitudinally polarized electron beam incident on a pressurized ^{4}He gaseous target placed within the CLAS spectrometer in Hall-B at the Thomas Jefferson National Accelerator Facility. The azimuthal angle (ϕ) dependence of the BSA was studied in a wide range of virtual photon and scattered proton kinematics. The Q^{2}, x_{B}, and t dependencies of the BSA on the bound proton are compared with those on the free proton. In the whole kinematical region of our measurements, the BSA on the bound proton is smaller by 20% to 40%, indicating possible medium modification of its partonic structure.

Use of Bevacizumab for Elderly Patients With Stage IV Colon Cancer: Analysis of SEER-Medicare Data

BACKGROUND

Bevacizumab is used for the treatment of metastatic colon cancer in conjunction with first-line chemotherapy. In this study, we examined receipt of first-line bevacizumab and predictors of its use among older patients with stage IV colon cancer.

MATERIALS AND METHODS

We used data from the Surveillance, Epidemiology, and End Results-Medicare dataset to identify patients with stage IV colon cancer diagnosed from 2005 to 2013 who received FOLFOX (5-fluorouracil/leucovorin/oxaliplatin) or FOLFIRI (5-fluorouracil/leucovorin/irinotecan) as first-line therapy. We used multivariable regression analysis to determine demographic and clinical factors associated with use of concomitant bevacizumab.

RESULTS

We identified 3785 patients with stage IV colon cancer who met our eligibility criteria. Of these, 2352 (62.1%) received bevacizumab. Bevacizumab use has decreased over time from 68.2% in 2005 to 57.6% in 2013 (odds ratio [OR], 0.94; 95% confidence interval [CI], 0.91-0.97). Patients were less likely to receive bevacizumab if they were older (compared with 65-69 years, ≥ 80 years: OR, 0.64; 95% CI, 0.52-0.80), or had multiple comorbidities (compared with comorbidity score of 0, score of 1: OR, 0.73; 95% CI, 0.60-0.89).

CONCLUSION

Over one-half of elderly patients received bevacizumab as part of their first-line therapy for stage IV colon cancer. Bevacizumab use has been slowly decreasing since 2005. Newer anti-epidermal growth factor receptor treatments have not been supplanting bevacizumab, as first-line biologic use in general has also decreased during this time period.

Direct Observation of Proton-Neutron Short-Range Correlation Dominance in Heavy Nuclei

We measured the triple coincidence A(e,e^{'}np) and A(e,e^{'}pp) reactions on carbon, aluminum, iron, and lead targets at Q^{2}>1.5  (GeV/c)^{2}, x_{B}>1.1 and missing momentum >400  MeV/c. This was the first direct measurement of both proton-proton (pp) and neutron-proton (np) short-range correlated (SRC) pair knockout from heavy asymmetric nuclei. For all measured nuclei, the average proton-proton (pp) to neutron-proton (np) reduced cross-section ratio is about 6%, in agreement with previous indirect measurements. Correcting for single-charge exchange effects decreased the SRC pairs ratio to ∼3%, which is lower than previous results. Comparisons to theoretical generalized contact formalism (GCF) cross-section calculations show good agreement using both phenomenological and chiral nucleon-nucleon potentials, favoring a lower pp to np pair ratio. The ability of the GCF calculation to describe the experimental data using either phenomenological or chiral potentials suggests possible reduction of scale and scheme dependence in cross-section ratios. Our results also support the high-resolution description of high-momentum states being predominantly due to nucleons in SRC pairs.

First Measurements of the Double-Polarization Observables F, P, and H in ω Photoproduction off Transversely Polarized Protons in the N^{*} Resonance Region

First measurements of double-polarization observables in ω photoproduction off the proton are presented using transverse target polarization and data from the CEBAF Large Acceptance Spectrometer (CLAS) FROST experiment at Jefferson Lab. The beam-target asymmetry F has been measured using circularly polarized, tagged photons in the energy range 1200-2700 MeV, and the beam-target asymmetries H and P have been measured using linearly polarized, tagged photons in the energy range 1200-2000 MeV. These measurements significantly increase the database on polarization observables. The results are included in two partial-wave analyses and reveal significant contributions from several nucleon (N^{*}) resonances. In particular, contributions from new N^{*} resonances listed in the Review of Particle Properties are observed, which aid in reaching the goal of mapping out the nucleon resonance spectrum.

FOLFOX and FOLFIRI Use in Stage IV Colon Cancer: Analysis of SEER-Medicare Data

BACKGROUND

Shortly after the year 2000, randomized trials demonstrated that patients with metastatic colon cancer treated with infusional 5-fluorouracil (5-FU)/leucovorin with either oxaliplatin (FOLFOX) or irinotecan (FOLFIRI) had a comparable progression-free survival benefit, superior to patients who received 5-FU/leucovorin alone. Factors associated with the initial receipt of the FOLFOX or FOLFIRI regimen are unknown. Our goal was to investigate the patterns and predictors of use for first-line FOLFOX and FOLFIRI.

PATIENTS AND METHODS

We used the Surveillance, Epidemiology, and End Results (SEER)-Medicare linked data set to identify patients with newly diagnosed stage IV colon cancer between the years 2005 and 2013 who received either first-line FOLFOX or FOLFIRI. We used logistic regression to assess demographic and clinical predictors for FOLFOX versus FOLFIRI. Survival was compared by Kaplan-Meier models.

RESULTS

Overall, 3000 patients (79.3%) received FOLFOX and 785 (20.7%) FOLFIRI. FOLFOX was associated with later year of diagnosis (odds ratio [OR] = 0.66, 95% confidence interval [CI], 0.54 to 0.82 for 2011-2013 vs. 2005-2007), being female (OR = 0.82; 95% CI 0.69 to 0.98), and living in the southern region of the United States. FOLFIRI was associated with having a higher comorbidity index (OR = 1.33; 95% CI, 1.07 to 1.67 for >1 comorbidity score vs. 0). There was no survival difference observed between the two treatments.

CONCLUSION

The majority of SEER-Medicare patients received FOLFOX and not FOLFIRI as a first-line treatment for stage IV colon cancer. Several demographic and clinical factors were associated with the use of each specific regimen. No survival difference was detected for the 2 groups.

Spores of Bacillus coagulans GBI-30, 6086 show high germination, survival and enzyme activity in a dynamic, computer-controlled in vitro model of the gastrointestinal tract

The aim of this study was to assess the germination, survival and metabolic activity of the probiotic Bacillus coagulans GBI-30, 6086 [GanedenBC³⁰] (BC30) in a dynamic, computer controlled in vitro model of the gastrointestinal (GI) tract, simulating human adults. Experiments were performed in the presence of a meal to maximise germination, due to the presence of germination-triggers. Both an upper GI tract (stomach and small intestine; TIM-1) and a colon model (TIM-2) were used, where material exiting TIM-1 was added to TIM-2. Spores of BC30 were introduced in the gastric compartment of TIM-1 and samples were taken immediately after the pylorus. Moreover, for 6 h, every hour the ileal efflux was collected and a subsample was plated for viable counts (spores and germinated cells). The remainder of the sample was fed to TIM-2, and after 24 h another sample was taken and tested for viable counts. In addition, samples were taken from the dialysates of the model and analysed using LC-MS/MS to determine bacterial metabolites and digestion products. Survival after transit through the gastric compartment was high (97%) and most cells were still in the spore form (76%). Survival after transit through TIM-1 was on average 51%, meaning that on average half of the orally provided spores was found back as cfu on the agar plates. Of these on average 93% were germinated cells and only 7% were spores. 24 h after the start of the experiments germination had increased in TIM-2 to 97% vegetative cells, and only 3% spores. No further loss of viability was observed in TIM-2. In terms of metabolic activity, increased levels of amino acids, dipeptides and citric acid cycle metabolites were found compared to experiments in the absence of BC30. In conclusion, BC30 spores germinate to a large extent (>90%) in the presence of germination triggers in the small intestine in a model that closely mimics the physiological conditions of human adults. Of the oral dose, as much as half of the cells survived transit through the upper GI tract, and based on the metabolite profile, these cells were metabolically active. Either these cells or the enzymes released from the dead cells aided in digestion of the meal. These insights help explain some of the observations in previous experiments, and support the understanding of the mechanism of action of the probiotic BC30.

Center of Mass Motion of Short-Range Correlated Nucleon Pairs studied via the A(e,e^{'}pp) Reaction

Short-range correlated (SRC) nucleon pairs are a vital part of the nucleus, accounting for almost all nucleons with momentum greater than the Fermi momentum (k_{F}). A fundamental characteristic of SRC pairs is having large relative momenta as compared to k_{F}, and smaller center of mass (c.m.) which indicates a small separation distance between the nucleons in the pair. Determining the c.m. momentum distribution of SRC pairs is essential for understanding their formation process. We report here on the extraction of the c.m. motion of proton-proton (pp) SRC pairs in carbon and, for the first time in heavier and ansymetric nuclei: aluminum, iron, and lead, from measurements of the A(e,e^{'}pp) reaction. We find that the pair c.m. motion for these nuclei can be described by a three-dimensional Gaussian with a narrow width ranging from 140 to 170  MeV/c, approximately consistent with the sum of two mean-field nucleon momenta. Comparison with calculations appears to show that the SRC pairs are formed from mean-field nucleons in specific quantum states.