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Matthew Fasullo,1 Yasir Al-Azzawi,1 Joan Kheder,1 Jeffrey Abergel,2 Wahid Wassef1 1Department of Gastroenterology, UMass Memorial Medical Center, Worcester, MA, USA; 2Department of Gastroenterology, Staten Island University Hospital, Staten Island, NY, USA Introduction: Mature peripancreatic fluid collection (MPFC) is a known and often challenging consequence of acute pancreatitis and often requires intervention. The most common method accepted is the “step-up approach,” which consists of percutaneous drainage followed, if necessary, by minimally invasive retroperitoneal necrosectomy. Our paper aims to distinguish between plastic stents and lumen-apposing stents in the endoscopic management of MPFC in terms of morbidity, mortality, and haste of fluid collection resolution. Methods: A retrospective analysis was performed at UMass Memorial Medical Center in patients with a diagnosis of MPFC. Utilizing medical records, clinical data, radiology, as well as endoscopic evidence, patients were differentiated by stent type used (plastic versus lumen-apposing) for the management of the MPFC. The primary outcome of the study was to assess the time to MPFC resolution following the placement of either plastic or lumen-apposing stents (on endoscopic ultrasound or computerized tomography scan) using a multivariate analysis with a logistic regression model. Results: A total of 54 patients were included in this study from UMass Memorial Medical Center between 2012 and 2015. Twelve (22%) of these patients received lumen-apposing stents and 42 (78%) of these patients received plastic pigtail stents. For the lumen-apposing stent group, the mean interval between stent placement and resolution of MPFC was 57 days as compared to 102 days for plastic pigtail stents (p=0.02). The mean interval for placement/removal of lumen-apposing stents was 48 days as compared to 81 days for plastic pigtail stents (p=0.01). Stent migration was seen in 5 patients (11%) who received a plastic pigtail stent compared to 0 (0%) patients who received a lumen-apposing stent. Discussion: Our study demonstrates that lumen-apposing stents result in a significant reduction in the interval between stent placement and MPFC resolution as well as the time from stent placement to removal, when compared to plastic pigtail stents, the prior standard-of-care. Our study reached similar conclusions regarding the number of stents placed. However, we did not find a significant difference between the complication rates, specifically peri- and postprocedural bleeding or perforation, between the 2 study groups, as demonstrated in prior papers. Keywords: pancreas, lumen-apposing, necrosectomy, fluid collection, plastic pigtail stent

We present a technique to measure the temperature dependence of the transverse piezoelectric coefficient e31, f of thin films of lead zirconate titanate (PZT), aluminum nitride, and BaTiO3 deposited on Si wafers. It is based on the collection of electric charges induced by the deflection of a Si cantilever coated with the piezoelectric film. The aim of this work is to assess the role of temperature in the decay of the remnant polarization of these materials, in particular, in optimized gradient-free PZT with composition PbZr0.52Ti0.48O3. It is found that in contrast to theoretical predictions, 31, f decreases with temperature because of the dominance of relaxation effects. The observation of steps in the logarithmic aging decay law is reminiscent of memory effects seen in frustrated spin glasses. [ABSTRACT FROM AUTHOR]

Abstract: This paper reports on the optimization of electrodes design for sol-gel Pb(Zr0.52, Ti0.48)O3 (PZT) thin-film actuated-membranes. PZT can be used in many actuator applications such as micro mirror, RF MEMS, inkjet or loudspeaker due to its strong piezoelectric properties. We aim to design membrane-based actuators with the optimum electrode dimensions allowing the largest membrane displacement under a given actuation voltage. We present in this paper measurement results, in good agreement with the finite element modeling, proving that an actuator area between 50 and 60% of the membrane area exhibits the highest deflection. [Copyright &y& Elsevier]

Background: To date, studies investigating the inflammatory bowel disease (IBD) patient experience with coronavirus disease 2019 (COVID-19) have consistently reported that the observed rate of COVID-19 within this population is similar to the general population. Limited research has suggested that corticosteroid use in the IBD population may be associated with worse COVID-19 outcomes, but it is still yet to be determined if specific IBD-related clinical factors are associated with worse outcomes. Our goal was to describe clinical COVID-19 outcomes for IBD patients and to identify the clinical factors that may be associated with worse outcomes., Methods: In this retrospective study, we utilized the inpatient database within the largest hospital network in the New York City Metropolitan area to identify all IBD patients with confirmed COVID-19., Results: Of 83 IBD/COVID-19 patients presenting to a hospital network emergency room, 56 were hospitalized. Overall, 19.6% of hospitalized IBD patients died, compared with 22.2% of all hospital system COVID-19 patients during the time period. There was no association between pre-admission corticosteroid use or biologic treatment with a severe course of COVID-19., Conclusions: In contrast to some prior reports, we did not observe an association of pre-admission corticosteroid use and adverse outcomes. While the mortality rate was high for IBD/COVID-19 patients, it was not greater than that for hospitalized COVID-19 patients generally. Though our results are encouraging, we continue to support the recommendations of the leading gastrointestinal and IBD societies to regard our patients as "at risk", and to observe caution in their care., Competing Interests: None to declare., (Copyright 2021, Sultan et al.)

Study aims  The goal of our study was to determine the current trends for inpatient utilization for endoscopic retrograde cholangiopancreatography (ERCP) and its economic impact in the United States between 2002 and 2013. Patients and methods  A Nationwide Inpatient Sample from 2002 through 2013 was examined. We identified ERCPs using International Classification of Diseases (ICD-9) codes; Procedure codes 51.10, 51.11, 52.13, 51.14, 51.15, 52.14 and 52.92 for diagnostic and 51.84, 51.86, 52.97 were studied. Rate of inpatient ERCP was calculated. The trends for therapeutic ERCPs were compared to the diagnostic ones. We analyzed patient and hospital characteristics, length of hospital stay, and cost of care after adjusting for weighted samples. We used the Cochran-Armitage test for categorical variables and linear regression for continuous variables. Results  A total of 411,409 ERCPs were performed from 2002 to 2013. The mean age was 59 ± 19 years; 61 % were female and 57 % were white. The total numbers of ERCPS increased by 12 % from 2002 to 2011, which was followed by a 10 % decrease in the number of ERCPs between 2011 and 2013. There was a significant increase in therapeutic ERCPs by 37 %, and a decrease in diagnostic ERCPs by 57 % from 2002 to 2013. Mean length of stay was 7 days (SE = 0.01) and the mean cost of hospitalization was $20,022 (SE = 41). Conclusions  Our large cross-sectional study shows a significant shift in ERCPs towards therapeutic indications and a decline in its conventional diagnostic utility. Overall there has been a reduction in inpatient ERCPs.

Background: Peptic ulcer disease (PUD) is a major public health burden significantly impacting the cost of hospitalization in the United States (US). We examined the trends, characteristics, complications, cost, and seasonality of PUD-related hospitalizations from 2000 to 2011., Methods: With the use of the Nationwide Inpatient Sample from 2000 through 2011, we identified PUD-related hospitalizations using the International Classification of Diseases (ICD-9), 9th Revision, and the Clinical Modification code 531.00 to 534.91 as the principal discharge diagnosis. The total number of hospitalizations for each calendar month of the year were added over a 12-year period, and this number was divided by the number of days in that particular month to obtain the mean hospitalizations per day for each month., Results: The study found that 351,921 hospitalizations with the primary discharge diagnosis of peptic ulcer disease (PUD) occurred in the US between 2000 and 2011. This number dropped significantly from 49,524 to 17,499 between 2000 and 2011, and the rate of PUD-related mortality decreased from 4.3% to 3.1%. The mean age of the study population was 66.2 ± 17.4 years; 52.3% were males, and 56.8% were white. The number of hospitalizations in the US peaked in the spring season (916/day), and reached a nadir in the fall season (861/day). The mean cost of PUD hospitalization increased significantly from $11,755 in 2001 to $13,803 in 2011 (relative increase of 17%; p <0.001)., Conclusion: The incidence of PUD and its mortality has decreased significantly in the last decade, but its economic burden on the healthcare system remains high. A seasonal pattern of PUD hospitalization showed a peak in PUD-related admissions in the spring season and a trough in the fall season., Competing Interests: The authors have declared that no competing interests exist.

A phenomenological approach is developed to identify the physical parameters causing the dc-voltage-induced tunability of aluminum nitride (AlN) acoustic resonators, widely used for RF filters. The typical resonance frequency of these resonators varies from 2.038 GHz at -200 V to 2.062 GHz at +200 V. This indicates, based on these RF measurements versus dc bias and the model used, that the AlN stiffness variation versus dc bias is the prominent effect because both resonance and antiresonance experience a similar variation, respectively, 24 MHz and 19 MHz at 400 V. Picosecond ultrasonics were also used to prove independently that the acoustic velocity (and therefore AlN stiffness) is sensitive to dc bias and that the variation induced is comparable to that extracted from the resonance measurements. It turned out that the stiffness relative variation for an electric field of 1 V/μm extracted from picosecond ultrasonics is 54 ppm-μm/V. This is in good agreement with the value extracted from the RF measurements, namely 57.2 ppm-μm/V. The overall tunability of these AlN resonators reaches 1.1%, which is an interesting figure, although probably not high enough for genuine applications.

Macrophages are major HIV target cells. They support both productive and latent HIV-1 infection. Susceptibility of primary macrophages to HIV depends on the anatomical location and activation state of the cells. We demonstrate that peritoneal macrophages (PMs) are abundant in ascitic fluid of patients with liver cirrhosis and are susceptible to HIV-1 infection. PMs expressed CD68, a differentiation marker, exhibited phagocytic activity, and survived in culture for 2 months without additional growth factors. Freshly isolated PMs were susceptible to HIV-1 R5 strains but not to X4-T-cell line-adapted strains. Interestingly, after 7 days in culture, PMs acquired susceptibility to X4-T-cell line-adapted strains. HIV entry inhibitors, TAK779 and AMD3100, blocked HIV infection of PMs, indicating that infection by R5 and X4 strains was mediated by CCR5 and CXCR4, respectively. Although PMs did not express detectable cell surface levels of CXCR4 and CCR5, they did express mRNAs of these HIV coreceptors and responded to stimulation by their natural ligands, SDF-1alpha and RANTES. PMs were susceptible to HIV-1 X4, R5, and X4R5 primary isolates. PMs after 7 days in culture produced greater amounts of X4 and X4R5 HIV than freshly isolated PMs. The day-7 PMs were more susceptible to R5 infection in a single-cycle infection assay, but there was no increase in viral production in a multiple-round infection assay. The level of CXCR4 mRNA and production of CC-chemokines (MIP-1alpha, MIP-1beta, and RANTES) increased significantly during 7 days in culture. Our results indicate that PMs are susceptible to receptor-mediated infection by a broad range of HIV strains. These primary macrophages could provide a valuable system for investigating the role of primary macrophages in HIV pathogenesis.

Background: Well-differentiated, "typical" carcinoid tumors traditionally have a very poor response to chemotherapy. We hypothesized that tumor specimens from well-differentiated carcinoid tumors would be highly resistant to the effects of chemotherapy when tested against a variety of antineoplastic agents in vitro., Methods: Ninety-eight typical carcinoid specimens were surgically harvested, cultured, and tested against antineoplastics in vitro. (3)H-Thymidine incorporation was used to assess the percentage of cell-growth inhibition (PCI) of tested specimens. PCI was used to determine if specimens had extreme drug resistance (EDR), intermediate drug resistance (IDR), or low drug resistance (LDR) to each reagent against which they were tested., Results: Seventy specimens generated results. Each was tested with an average of six drugs. The mean proportions of drugs classified as LDR, IDR, and EDR were 0.48 (range 0-1), 0.34 (range 0-1), and 0.18 (range 0-0.80), respectively. The mean numbers of drugs per specimen exhibiting LDR, IDR, and EDR chemoresistance were 2.7, 2.1, and 1.2, respectively. 57 of 70 specimens (81%) had LDR to at least two drugs. 5-FU had the highest frequency of low chemoresistance at 69%, followed by doxorubicin at 67%. Low in vitro resistance to chemotherapeutics was prevalent among typical carcinoids, while EDR was comparatively infrequent., Conclusions: This implies that there may be less clinical chemoresistance and more chemosensitivity among typical carcinoid tumors than clinical trials have previously revealed. These findings warrant additional investigations assessing the response of carcinoid tumors to assay-guided chemotherapy regimens.