Percutaneous Cholecystostomy: Procedural Guidance and Future Directions for Clinical Management.

Percutaneous cholecystostomy (PC) is a recognized treatment option for the management of acute cholecystitis and is an integral component of the treatment algorithm in the 2018 Tokyo Guidelines. The utilization of PC has significantly increased over the past 30 years, particularly in the setting of critically ill patients and those with extensive comorbidities who are poor surgical candidates. The indications, complications, patient selection considerations, and technical complexities of the procedure will be discussed.

RNA polymerases reshape chromatin architecture and couple transcription on individual fibers.

RNA polymerases must initiate and pause within a complex chromatin environment, surrounded by nucleosomes and other transcriptional machinery. This environment creates a spatial arrangement along individual chromatin fibers ripe for both competition and coordination, yet these relationships remain largely unknown owing to the inherent limitations of traditional structural and sequencing methodologies. To address this, we employed long-read chromatin fiber sequencing (Fiber-seq) in Drosophila to visualize RNA polymerase (Pol) within its native chromatin context with single-molecule precision along up to 30 kb fibers.

Single-nucleoid architecture reveals heterogeneous packaging of mitochondrial DNA.

Cellular metabolism relies on the regulation and maintenance of mitochondrial DNA (mtDNA). Hundreds to thousands of copies of mtDNA exist in each cell, yet because mitochondria lack histones or other machinery important for nuclear genome compaction, it remains unresolved how mtDNA is packaged into individual nucleoids. In this study, we used long-read single-molecule accessibility mapping to measure the compaction of individual full-length mtDNA molecules at near single-nucleotide resolution.

RNA polymerases reshape chromatin and coordinate transcription on individual fibers.

During eukaryotic transcription, RNA polymerases must initiate and pause within a crowded, complex environment, surrounded by nucleosomes and other transcriptional activity. This environment creates a spatial arrangement along individual chromatin fibers ripe for both competition and coordination, yet these relationships remain largely unknown owing to the inherent limitations of traditional structural and sequencing methodologies. To address these limitations, we employed long-read chromatin fiber sequencing (Fiber-seq) to visualize RNA polymerases within their native chromatin context at single-molecule and near single-nucleotide resolution along up to 30 kb fibers.

Comparing outcomes of percutaneous cholecystostomy drain placement between patients within and outside of Tokyo guidelines diagnostic criteria for acute cholecystitis.

Objective: To compare outcomes following percutaneous cholecystostomy drain placement based on presence or absence of Tokyo Guidelines diagnostic criteria for acute cholecystitis.

Methods: Chart review was performed to identify the presence or absence of Tokyo Guidelines diagnostic criteria for acute cholecystitis in 146 patients who underwent percutaneous cholecystostomy between 2012 and 2015. Those who met criteria were compared to those who did not in terms of demographics, laboratory values, drain indwelling time, treatment response, eventual surgical management, and 30-day mortality.