A new and improved transjugular intrahepatic portosystemic shunt (TIPS) stent graft: Controlled expansion

Initial underdilation of transjugular intrahepatic portosystemic shunt (TIPS) stents has been a widely proposed and commonly practiced technique to balance portal hypertension relief and the adverse effects associated with excess shunting, especially hepatic encephalopathy. However, this technique has been scrutinized by a number of studies which have shown that underdilated TIPS stents tend to passively expand with time. The recently launched GORE® VIATORR® TIPS Endoprosthesis with Controlled Expansion (VIATORR CX®) may address this problem with its novel diameter control capabilities. This article reviews literature concerning passive expansion of initially underdilated TIPS stents and explores preliminary data investigating the use and efficacy of the VIATORR CX® endoprosthesis

Development of a water Cherenkov detector prototype with wavelength shifters and silicon photomultiplier readout

© Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0). Indirect high energy cosmic and gamma ray experiments require cost effective detectors and a large coverage area. Water Cherenkov detectors with large photomultiplier tubes have been commonly used for these experiments. While the photomultiplier tubes have good dynamic range and could be manufactured to larger sizes, their main drawbacks are high voltage to operate and sensitivity to magnetic fields. Silicon photomultipliers are the solid state counterparts which are insensitive to magnetic fields and operate at lower voltage, but have smaller area. At a time when solid state silicon photomultiplier vendors are growing and photomultiplier tubes declining, it is of paramount importance to develop alternative cost-effective readout schemes for future experiments. We developed a prototype water Cherenkov detector with wavelength shifting fibers and silicon photomultiplier readout. We report on the performance of this prototype for cosmic ray muons. We used Geant4 simulations to extrapolate performance at larger sizes

Transarterial Chemoembolization of Hepatocellular Carcinoma with Oncozene Microspheres: An Initial, Short-Term Clinical Experience-A Retrospective, Matched, Comparison Study.

Background: The purpose of this study is to describe a single institutions experience using Oncozene (OZ) microspheres for transarterial chemoembolization (OZ-TACE) of hepatocellular carcinoma (HCC), and to compare tolerability, safety, short-term radiographic tumor response, progression-free survival (PFS), and overall survival (OS) of these procedures to TACE (LC-TACE) performed with LC beads (LC). Methods: A retrospective, matched cohort study of patients undergoing DEB-TACE (drug-eluting bead transarterial chemoembolization) with OZ or LC was performed. The cohort comprised 23 patients undergoing 29 TACE with 75 or 100 μm OZ and 24 patients undergoing 29 TACE with 100-300 μm LC. Outcome measures were changes in liver function tests, complications, treatment tolerability, short-term radiographic tumor response according to modified RECIST criteria for HCC, PFS, and 1-year OS. The Mann-Whitney U test, Fisher exact test, and log rank test were used to compare the groups. Results: The BCLC or Child-Pugh scores were similar between the OZ and LC group. However, the two groups differed with respect to the etiology of background cirrhosis (p = 0.02). All other initial demographic and tumor characteristics were similar between the two groups. OZ-TACE used less doxorubicin per treatment compared to LC-TACE (median 50 vs. 75 mg; p = 0.0005). Rates of pain, nausea, and postembolization syndrome were similar, irrespective of the embolic agent used. OZ-TACE resulted in an overall complication rate comparable to LC-TACE (20.7% vs. 10.3%; p = 0.47). LC-TACE resulted in a higher percent increase in total bilirubin on post-procedure day 1 (median 18.8 vs. 0%; p = 0.05), but this difference resolved at 1 month. Both OZ-TACE and LC-TACE resulted in similar complete (31% vs. 24%) and objective (66% vs. 79%) target lesion response rates on 1-month post-TACE imaging. Both OZ-TACE and LC-TACE had similar median progression-free survival (283 vs. 209 days; p = 0.14) and 1-year overall survival rates (85% vs. 76%; p = 0.30). Conclusion: With a significantly reduced dose of doxorubicin, TACE performed with Oncozene microspheres in a heterogeneous patient population is well-tolerated, safe, and produces a similar radiological response and survival rate when compared to LC Bead TACE

Predictive Modeling of Colonoscopic Findings in a Fecal Immunochemical Test-Based Colorectal Cancer Screening Program.

BackgroundThe fecal immunochemical test (FIT) is the primary modality used by the Los Angeles County Department of Health Services (LADHS) for colorectal cancer (CRC) screening in average-risk patients. Some patients referred for FIT-positive diagnostic colonoscopy have neither adenomas nor more advanced pathology. We aimed to identify predictors of false-positive FIT (FP-FIT) results in our largely disenfranchised, low socioeconomic status population.MethodsWe conducted a retrospective study of 596 patients who underwent diagnostic colonoscopy following a positive screening FIT. Colonoscopies showing adenomas (or more advanced pathology) were considered positive. We employed multiple logistic and linear regression as well as machine learning models (MLMs) to identify clinical predictors of FP-FIT (primary outcome) and the presence of advanced adenomas (secondary outcome).ResultsOverall, 268 patients (45.0%) had a FP-FIT. Female sex and hemorrhoids (odds ratios [ORs] 1.59 and 1.89, respectively) were associated with increased odds of FP-FIT and fewer advanced adenomas (β = - 0.658 and  - 0.516, respectively). Conversely, increasing age and BMI (ORs 0.94 and 0.96, respectively) were associated with decreased odds of FP-FIT and a greater number of advanced adenomas (β = 0.073 and 0.041, respectively). MLMs predicted FP-FIT with high specificity (93.8%) and presence of advanced adenoma with high sensitivity (94.4%).ConclusionIncreasing age and BMI are associated with lower odds of FP-FIT and greater number of advanced adenomas, while female sex and hemorrhoids are associated with higher odds of FP-FIT and fewer advanced adenomas. The presence of the aforementioned predictors may inform the decision to proceed with diagnostic colonoscopy in FIT-positive patients

The Bacillus subtilis cell-division 135-137 degrees region contains an essential orf with significant similarity to murB and a dispensable sbp gene

Sequence similarity analysis has revealed that orf2, in the cell division 135-137 degrees region of the Bacillus subtilis (Bs) chromosome, is the probable homolog of Escherichia coli murB (encoding a reductase involved in peptidoglycan synthesis). The amino-acid sequences of the two protein products show 24% identity (47% overall similarity), with several regions of higher similarity which may represent functional domains of the proteins. Attempts to insertionally inactivate orf2 were unsuccessful, strongly suggesting that it is an essential Bs gene. A small gene found in the same region as orf2, sbp (encoding the 'small basic protein'), was shown to be non-essential in Bs

Machine learning models compared to existing criteria for noninvasive prediction of endoscopic retrograde cholangiopancreatography-confirmed choledocholithiasis

Background and aimsNoninvasive predictors of choledocholithiasis have generally exhibited marginal performance characteristics. We aimed to identify noninvasive independent predictors of endoscopic retrograde cholangiopancreatography (ERCP)-confirmed choledocholithiasis and accordingly developed predictive machine learning models (MLMs).MethodsClinical data of consecutive patients undergoing first-ever ERCP for suspected choledocholithiasis from 2015-2019 were abstracted from a prospectively-maintained database. Multiple logistic regression was used to identify predictors of ERCP-confirmed choledocholithiasis. MLMs were then trained to predict ERCP-confirmed choledocholithiasis using pre-ERCP ultrasound (US) imaging only and separately using all available noninvasive imaging (US/CT/magnetic resonance cholangiopancreatography). The diagnostic performance of American Society for Gastrointestinal Endoscopy (ASGE) "high-likelihood" criteria was compared to MLMs.ResultsWe identified 270 patients (mean age 46 years, 62.2% female, 73.7% Hispanic/Latino, 59% with noninvasive imaging positive for choledocholithiasis) with native papilla who underwent ERCP for suspected choledocholithiasis, of whom 230 (85.2%) were found to have ERCP-confirmed choledocholithiasis. Logistic regression identified choledocholithiasis on noninvasive imaging (odds ratio (OR) = 3.045, P = 0.004) and common bile duct (CBD) diameter on noninvasive imaging (OR=1.157, P = 0.011) as predictors of ERCP-confirmed choledocholithiasis. Among the various MLMs trained, the random forest-based MLM performed best; sensitivity was 61.4% and 77.3% and specificity was 100% and 75.0%, using US-only and using all available imaging, respectively. ASGE high-likelihood criteria demonstrated sensitivity of 90.9% and specificity of 25.0%; using cut-points achieving this specificity, MLMs achieved sensitivity up to 97.7%.ConclusionsMLMs using age, sex, race, presence of diabetes, fever, body mass index (BMI), total bilirubin, maximum CBD diameter, and choledocholithiasis on pre-ERCP noninvasive imaging predict ERCP-confirmed choledocholithiasis with good sensitivity and specificity and outperform the ASGE criteria for patients with suspected choledocholithiasis

Clinical Features and Outcomes of Patients with Pancreaticobiliary Malignancies in Los Angeles County and Their Association with CA 19-9 Levels

Although CA 19-9 is a commonly used tumor marker in the management of PBMs, the literature describing outcomes in patients with PBMs who have undetectable or low (hereinafter "low") CA 19-9 levels remains scarce. In this study, we sought to compare clinical features and outcomes in patients with PBMs and low CA 19-9 levels to those with normal and elevated CA 19-9 levels.MethodsWe retrospectively collected data on patients with biopsy-confirmed PBMs and stratified patients into categories based on their CA 19-9 level at diagnosis. Survival curves were estimated for patients in each of the three aforementioned CA 19-9 groups using the Kaplan-Meier method and compared using a Cox proportional hazards regression model.ResultsOf the 283 patients identified, 23 (8.1%) had low, 70 (24.7%) had normal, and 190 (67.1%) had elevated CA 19-9 levels. After controlling for sex, age, BMI, the presence of metastases at the time of diagnosis, and treatment with curative intent, the hazard ratio for death in the elevated CA 19-9 group compared to the low CA 19-9 group was 1.993 (95% CI 1.089-3.648; p = 0.025).ConclusionThe elevated CA 19-9 level compared to the low CA 19-9 level and the presence of metastases were associated with an increased hazard of death, while treatment with curative intent was associated with a decreased hazard of death

Clinical epidemiology and outcomes of patients with gastric intestinal metaplasia in the Los Angeles County System

BackgroundGastric intestinal metaplasia (GIM) is a precursor to gastric adenocarcinoma (GAC). In the United States, there is no consensus on the utility of surveillance for GIM, and minority populations most affected by GAC are understudied. Our aims were to define clinical and endoscopic features, surveillance practices, and outcomes in patients with GIM in a multicenter safety-net system.MethodsWe identified patients with biopsy-proven GIM between 2016-2020 at the three medical centers comprising Los Angeles County Department of Health Services. Demographics, findings at index esophagogastroduodenoscopy (EGD) first showing GIM, recommended interval for repeat EGD, and findings at repeat EGD were abstracted. Descriptive statistics were performed to characterize our cohort. T-tests and chi-squared (χ2) tests were used to compare patients with and without multifocal GIM.ResultsThere were 342 patients with newly-diagnosed biopsy-proven GIM, 18 (5.2%) of whom had GAC at index EGD. Hispanic patients comprised 71.8% of patients. For most patients (59%), repeat EGD was not recommended. If recommended, 2-3 years was the most common interval. During a median time to repeat EGD of 13 months and cumulative follow-up of 119 patient-years, 29.5% of patients underwent at least one repeat EGD, of whom 14% had multifocal GIM not previously detected. Progression to dysplasia or GAC was not detected in any patients.ConclusionIn a predominantly minority population with biopsy-proven GIM, there was a 5% incidence of GAC on index EGD. Though progression to neither dysplasia nor GAC was detected, there was significant variability in endoscopic sampling and surveillance practices

Yield of Post-Acute Diverticulitis Colonoscopy for Ruling Out Colorectal Cancer.

Background and aimsColonoscopy is recommended post-acute diverticulitis (AD) to exclude underlying adenocarcinoma (CRC). However, post-AD colonoscopy utility remains controversial. We aimed to examine yield of post-AD colonoscopy in our majority-Hispanic patient population.MethodsPatients undergoing post-AD colonoscopy between 11/1/2015-7/31/2021 were identified from a prospectively maintained endoscopic database. AD cases without computed tomography confirmation were excluded. Pertinent data, including complicated vs uncomplicated AD, fecal immunochemical test (FIT) result post-AD/pre-colonoscopy, and number/type/location of non-advanced adenomas, advanced adenomas, and CRC, were abstracted. Analyses were conducted using two-sample Wilcoxon rank-sum and Fisher's exact tests.Results208 patients were included, of whom 62.0% had uncomplicated AD. Median age was 53, 54.3% were female, and 77.4% were Hispanic. Ninety non-advanced adenomas were detected in 45 patients (21.6%), in addition to advanced adenoma in eight patients (3.8%). Two patients (1.0%) had CRC, both of whom had complicated AD in the same location seen on imaging, and one of whom was FIT+ (the other had not undergone FIT). Patients with uncomplicated versus complicated AD had similarly low rates of advanced adenomas (4.7% vs. 2.5%, p=0.713). FIT data were available in 51 patients and positive in three (5.9%); non-advanced adenomas were found in all three FIT+ patients. No FIT- patient had an advanced adenoma or CRC.ConclusionColonoscopy post-AD is generally low yield, with CRC being rare and found only in those with complicated AD. Colonoscopy post-complicated AD appears advisable, whereas less invasive testing (e.g. FIT) may be considered post-uncomplicated AD to inform the need for colonoscopy