Dietary guideline adherence for gastroesophageal reflux disease.

BackgroundGastroesophageal reflux disease (GERD) is the most common gastrointestinal disease, and the cost of health care and lost productivity due to GERD is extremely high. Recently described side effects of long-term acid suppression have increased the interest in nonpharmacologic methods for alleviating GERD symptoms. We aimed to examine whether GERD patients follow recommended dietary guidelines, and if adherence is associated with the severity and frequency of reflux symptoms.MethodsWe conducted a population-based cross-sectional study within the Kaiser Permanente Northern California population, comparing 317 GERD patients to 182 asymptomatic population controls. All analyses adjusted for smoking and education.ResultsGERD patients, even those with moderate to severe symptoms or frequent symptoms, were as likely to consume tomato products and large portion meals as GERD-free controls and were even more likely to consume soft drinks and tea [odds ratio (OR) = 2.01 95% confidence interval (CI) 1.12-3.61; OR = 2.63 95% CI 1.24-5.59, respectively] and eat fried foods and high fat diet. The only reflux-triggering foods GERD patients were less likely to consume were citrus and alcohol [OR = 0.59; 95% CI: 0.35-0.97 for citrus; OR = 0.41 95% CI 0.19-0.87 for 1 + drink/day of alcohol]. The associations were similar when we excluded users of proton pump inhibitors.ConclusionsGERD patients consume many putative GERD causing foods as frequently or even more frequently than asymptomatic patients despite reporting symptoms. These findings suggest that, if dietary modification is effective in reducing GERD, substantial opportunities for nonpharmacologic interventions exist for many GERD patients

Reducing Variation in the “Standard of Care” for Cancer Screening

Standard of care for cancer screening: the term implies certainty and consensus. Physicians, patients, and organizations have created guidelines, policies, and regulations regarding how, when, and for whom screening should be used or reimbursed; cumulatively, these statements become the standards of care. However, these standards vary markedly across organ type, often without rationale or evidence. In this Viewpoint, we highlight 3 areas in which cancer screening standards differ markedly for breast, colorectal, and cervical cancer: funding, quality measures, and reporting. These variations were delineated through a cross-disciplinary collaboration among scientists, health care organizations, and society leaders within the National Cancer Institute’s (NCI’s) Population-Based Research Optimizing Screening Through Personalized Regimens (PROSPR) consortium.1 PROSPR studies how breast, cervical, and colorectal cancer screening is implemented in diverse, real-world settings

Oral Bisphosphonate Exposure and the Risk of Upper Gastrointestinal Cancers

The association between oral bisphosphonate use and upper gastrointestinal cancer has been controversial. Therefore, we examined the association with esophageal and gastric cancer within the Kaiser Permanente, Northern California population. A total of 1,011 cases of esophageal (squamous cell carcinoma and adenocarcinoma) and 1,923 cases of gastric adenocarcinoma (cardia, non-cardia and other) diagnosed between 1997 and 2011 from the Kaiser Permanente, Northern California cancer registry were matched to 49,886 and 93,747 controls, respectively. Oral bisphosphonate prescription fills at least one year prior to the index date were extracted. Conditional logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (95% CI) for the associations between prospectively evaluated oral bisphosphonate use with incident esophageal and gastric cancer diagnoses with adjustment for potential confounders. After adjustment for potential confounders, no significant associations were found for esophageal squamous cell carcinoma (OR 0.88; 95% CI: 0.51, 1.52), esophageal adenocarcinoma (OR 0.68; 95% CI: 0.37, 1.24), or gastric non-cardia adenocarcinoma (OR 0.83, 95% CI: 0.59, 1.18), but we observed an adverse association with gastric cardia adenocarcinoma (OR 1.64; 95% CI: 1.07, 2.50). In conclusion, we observed no association between oral bisphosphonate use and esophageal cancer risk within a large community-based population. A significant association was detected with gastric cardia and other adenocarcinoma risk, although this needs to be replicated

Approaches for classifying the indications for colonoscopy using detailed clinical data

BACKGROUND: Accurate indication classification is critical for obtaining unbiased estimates of colonoscopy effectiveness and quality improvement efforts, but there is a dearth of published systematic classification approaches. The objective of this study was to evaluate the effects of data-source and adjudication on indication classification and on estimates of the effectiveness of screening colonoscopy on late-stage colorectal cancer diagnosis risk. METHODS: This was an observational study in members of four U.S. health plans. Eligible persons (n = 1039) were age 55-85 and had been enrolled for 5 years or longer in their health plans during 2006-2008. Patients were selected based on late-stage colorectal cancer diagnosis in a case-control design; each case patient was matched to 1-2 controls by study site, age, sex, and health plan enrollment duration. Reasons for colonoscopies received in the 10-year period before the reference date were collected from three medical records sources (progress notes; referral notes; procedure reports) and categorized using an algorithm, with committee adjudication of some tests. We evaluated indication classification concordance before and after adjudication and used logistic regressions with the Wald Chi-square test to compare estimates of the effects of screening colonoscopy on late-stage colorectal cancer diagnosis risk for each of our data sources to the adjudicated indication. RESULTS: Classification agreement between each data-source and adjudication was 78.8-94.0% (weighted kappa = 0.53-0.72); the highest agreement (weighted kappa = 0.86-0.88) was when information from all data sources was considered together. The choice of data-source influenced the association between screening colonoscopy and late-stage colorectal cancer diagnosis; estimates based on progress notes were closest to those based on the adjudicated indication (% difference in regression coefficients = 2.4%, p-value = 0.98), as compared to estimates from only referral notes (% difference in coefficients = 34.9%, p-value = 0.12) or procedure reports (% difference in coefficients = 27.4%, p-value = 0.23). CONCLUSION: There was no single gold-standard source of information in medical records. The estimates of colonoscopy effectiveness from progress notes alone were the closest to estimates using adjudicated indications. Thus, the details in the medical records are necessary for accurate indication classification

Bosonization of non-relativstic fermions in 2-dimensions and collective field theory

We revisit bosonization of non-relativistic fermions in one space dimension. Our motivation is the recent work on bubbling half-BPS geometries by Lin, Lunin and Maldacena (hep-th/0409174). After reviewing earlier work on exact bosonization in terms of a noncommutative theory, we derive an action for the collective field which lives on the droplet boundaries in the classical limit. Our action is manifestly invariant under time-dependent reparametrizations of the boundary. We show that, in an appropriate gauge, the classical collective field equations imply that each point on the boundary satisfies Hamilton's equations for a classical particle in the appropriate potential. For the harmonic oscillator potential, a straightforward quantization of this action can be carried out exactly for any boundary profile. For a finite number of fermions, the quantum collective field theory does not reproduce the results of the exact noncommutative bosonization, while the latter are in complete agreement with the results computed directly in the fermi theory.Comment: references added and typos corrected; 21 pages, 3 figures, eps

Moduli Space Metric of N=2 Supersymmetric SU(N) Gauge Theory and the Enhancon

We compute the moduli space metric of SU(N) Yang-Mills theory with N=2 supersymmetry in the vicinity of the point where the classical moduli vanish. This gauge theory may be realized as a set of N D7-branes wrapping a K3 surface, near the enhancon locus. The moduli space metric determines the low-energy worldvolume dynamics of the D7 branes near this point, including stringy corrections. Non-abelian gauge symmetry is not restored on the worldvolume at the enhancon point, but rather the gauge group remains U(1)^{N-1} and light electric and magnetically charged particles coexist. We also study the moduli space metric for a single probe brane in the background of N-1 branes near the enhancon point. We find quantum corrections to the supergravity probe metric that are not suppressed at large separations, but are down by 1/N factors, due to the response of the N-1 enhancon branes to the probe. A singularity appears before the probe reaches the enhancon point where a dyon becomes massless. We compute the masses of W-bosons and monopoles in a large N limit near this critical point.Comment: 20 pages, 2 figure

LSZ in LST

We discuss the analytic structure of off-shell correlation functions in Little String Theories (LSTs) using their description as asymptotically linear dilaton backgrounds of string theory. We focus on specific points in the LST moduli space where this description involves the spacetime (R^{d-1,1} times SL(2)/U(1) times a compact CFT), though we expect our qualitative results to be much more general. We show that n-point functions of vertex operators O(p) have single poles as a function of the d-dimensional momentum p, which correspond to normalizable states localized near the tip of the SL(2)/U(1) cigar. Additional poles arise due to the non-trivial dynamics in the bulk of the cigar, and these can lead to a type of UV/IR mixing. Our results explain some previously puzzling features of the low energy behavior of the Green functions. As another application, we compute the precise combinations of single-trace and multi-trace operators in the low-energy gauge theory which map to single string vertex operators in the N=(1,1) supersymmetric d=6 LST. We also discuss the implications of our results for two dimensional string theories and for the (non-existence of a) Hagedorn phase transition in LSTs.Comment: 93 pages; harvmac. v2: minor changes. v3: Added reference and minor change

Strings in flat space and pp waves from N=4{\cal N}=4 Super Yang Mills

We explain how the string spectrum in flat space and pp-waves arises from the large $N$ limit, at fixed $g^2_{YM}$, of U(N) ${\cal N} =4$ super Yang Mills. We reproduce the spectrum by summing a subset of the planar Feynman diagrams. We give a heuristic argument for why we can neglect other diagrams. We also discuss some other aspects of pp-waves and we present a matrix model associated to the DLCQ description of the maximally supersymmetric eleven dimensional pp-waves.Comment: 36 pages, 5 figures. v3: minor typos corrected, references adde

Dynamics of Giant-Gravitons in the LLM geometry and the Fractional Quantum Hall Effect

The LLM's 1/2 BPS solutions of IIB supergravity are known to be closely related to the integer quantum Hall droplets with filling factor $\nu=1$, and the giant gravitons in the LLM geometry behave like the quasi-holes in those droplets. In this paper we consider how the fractional quantum Hall effect may arise in this context, by studying the dynamics of giant graviton probes in a special LLM geometry, the AdS_5 X S^5 background, that corresponds to a circular droplet. The giant gravitons we study are D3-branes wrapping on a 3-sphere in S^5. Their low energy world-volume theory, truncated to the 1/2 BPS sector, is shown to be described by a Chern-Simons finite-matrix model. We demonstrate that these giant gravitons may condense at right density further into fractional quantum Hall fluid due to the repulsive interaction in the model, giving rise to the new states in IIB string theory. Some features of the novel physics of these new states are discussed.Comment: 32 pages, 1 figure; v.2: references added, the relation between the level shift and filling fraction elaborate