The University of West Florida Campus Ecosystem Study: effects of forest vegetation on light availability and soil processes.

College and university campuses with a notable arboreal component provide unique opportunities for carrying out ecological research. The University of West Florida Campus Ecosystem Study (UWF CES) was established in 2019 as interconnected research to take advantage of the extensive arborescent nature of the UWF campus, particularly concerning longleaf pine (Pinus palustris). One of these investigations established permanent plots in forested sites of two contrasting types, one dominated by longleaf pine ("pine site") and the other dominated by hardwoods ('hardwood site'). This study used these plots to examine the influence of forest vegetation on light availability and soil processes. Light was measured as photosynthetically active radiation (and expressed as photon flux density-PFD) with a handheld meter in each plot. Soil was sampled to 5 cm in each plot; texture was measured with the hydrometer method. Identical sampling methods were carried out in a persistent canopy opening to assess light and soil conditions under maximum solar radiation. Mean PFD was ~4× higher in pine stands than in hardwood stands; PFD was 12.8 and 3.5% of full light in the pine and hardwood stands, respectively. All soils were dominated by coarse-textured sands, but silt was significantly higher in pine stand soil and higher still in the canopy opening. Among forest stand plots, sand was negatively related to PFD, whereas clay was positively related to PFD. Across the three sites, silt was positively related to PFD. These relationships are consistent with the importance of solar radiation as one of many drivers of soil weathering.

Afferent Loop Syndrome as Second Presentation of Gastric Outlet Obstruction in Patient With Billroth II Anatomy.

Afferent loop syndrome can result from both benign and malignant strictures of the biliary limbs of patients with surgically altered anatomy. Afflicted patients accumulate intestinal and pancreaticobiliary secretions, which leads to bowel distention and pain. We describe the endoscopic management of a 52-year-old woman with a history of Billroth II gastrojejunostomy due to gastric cancer who developed malignant gastric outlet obstruction and subsequently malignant afferent loop syndrome, using lumen-apposing metal stents.

A Prospective Cohort Study Evaluating PAN-PROMISE, a Patient-reported Outcome Measure to Detect Post-ERCP Morbidity.

BACKGROUND & AIMS: The Cotton Consensus (CC) criteria for post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP) may not capture post-ERCP morbidity. PAN-PROMISE, a patient-reported outcome measure (PROM), was developed to quantify acute pancreatitis-related morbidity. This study aims to determine the value of PAN-PROMISE in independently defining ERCP-related morbidity. METHODS: We conducted a prospective cohort study of patients undergoing ERCP at 2 academic centers from September 2021 to August 2022. We administered PAN-PROMISE and assessed quality of life and work productivity at baseline, 48 to 72 hours, 7 days, and 30 days following ERCP. PEP was defined by a 3-physician committee using the CC criteria. We defined high morbidity following ERCP (elevated PROM) by an increase of PAN-PROMISE score of >7 at 7 days post-procedure. The McNemar test assessed discordance between PEP and elevated-PROM. RESULTS: A total of 679 patients were enrolled. Choledocholithiasis (30%) and malignant biliary obstruction (29%) were the main indications for ERCP. Thirty-two patients (4.7%) developed PEP. One hundred forty-seven patients (21.6%) had an elevated PROM, whereas only 20 of them (13.4%) had PEP by the CC criteria (P < .001 for discordance). An elevated PROM strongly correlated with lower physical quality of life and increased direct and indirect health care costs ($80 and $25 per point increase in PAN-PROMISE, respectively). Patients with pancreatic cancer (odds ratio, 4.52; 95% confidence interval, 1.68-10.74) and primary sclerosing cholangitis (odds ratio, 1.79; 95% confidence interval, 1.29-2.45) had the highest odds of elevated PROM. CONCLUSIONS: A substantial number of patients experience significant morbidity after ERCP despite not developing PEP or other adverse events. Future studies are needed to characterize better the reasons behind this increase in symptoms and potential interventions to reduce the symptom burden post-ERCP. CLINICALTRIALS: gov number, NCT05310409.

Gill microbiome structure and function in the chemosymbiotic coastal lucinid Stewartia floridana.

Lucinid bivalves harbor environmentally acquired, chemosynthetic, gammaproteobacterial gill endosymbionts. Lucinid gill microbiomes, which may contain other gammaproteobacterial and/or spirochete taxa, remain under-sampled. To understand inter-host variability of the lucinid gill microbiome, specifically in the bacterial communities, we analyzed the microbiome content of Stewartia floridana collected from Florida. Sampled gills contained a monospecific gammaproteobacterial endosymbiont expressing lithoautotrophic, mixotrophic, diazotrophic and C1 compound oxidation-related functions previously characterized in similar lucinid species. Another low-abundance Spirochaeta-like species in ∼72% of the sampled gills was most closely related to Spirochaeta-like species in another lucinid Phacoides pectinatus and formed a clade with known marine Spirochaeta symbionts. The spirochete expressed genes were involved in heterotrophy and the transport of sugars, amino acids, peptides and other substrates. Few muscular and neurofilament genes from the host and none from the gammaproteobacterial and spirochete symbionts were differentially expressed among quadrats predominantly covered with seagrass species or 80% bare sand. Our results suggest that spirochetes are facultatively associated with S. floridana, with potential scavenging and nutrient cycling roles. Expressed stress- and defense-related functions in the host and symbionts also suggest species-species communications, which highlight the need for further study of the interactions among lucinid hosts, their microbiomes and their environment.

Correction: Taxonomic and functional heterogeneity of the gill microbiome in a symbiotic coastal mangrove lucinid species.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Taxonomic and functional heterogeneity of the gill microbiome in a symbiotic coastal mangrove lucinid species.

Lucinidae clams harbor gammaproteobacterial thioautotrophic gill endosymbionts that are environmentally acquired. Thioautotrophic lucinid symbionts are related to metabolically similar symbionts associated with diverse marine host taxa and fall into three distinct phylogenetic clades. Most studies on the lucinid-bacteria chemosymbiosis have been done with seagrass-dwelling hosts, whose symbionts belong to the largest phylogenetic clade. In this study, we examined the taxonomy and functional repertoire of bacterial endosymbionts at an unprecedented resolution from Phacoides pectinatus retrieved from mangrove-lined coastal sediments, which are underrepresented in chemosymbiosis studies. The P. pectinatus thioautotrophic endosymbiont expressed metabolic gene variants for thioautotrophy, respiration, and nitrogen assimilation distinct from previously characterized lucinid thioautotrophic symbionts and other marine symbionts. At least two other bacterial species with different metabolisms were also consistently identified in the P. pectinatus gill microbiome, including a Kistimonas-like species and a Spirochaeta-like species. Bacterial transcripts involved in adhesion, growth, and virulence and mixotrophy were highly expressed, as were host-related hemoglobin and lysozyme transcripts indicative of sulfide/oxygen/CO2 transport and bactericidal activity. This study suggests the potential roles of P. pectinatus and its gill microbiome species in mangrove sediment biogeochemistry and offers insights into host and microbe metabolisms in the habitat.

Impact of low-kVp scan technique on oral contrast density at abdominopelvic CT.

PURPOSE: To assess quantitative and qualitative effects of kVp on oral contrast density. MATERIALS AND METHODS: Three readers retrospectively reviewed 100 CT scans performed at a range of high- and low-energy settings, independently determining their preferred window and level settings for evaluation of the oral-contrast-opacified bowel. Contrast density was also assessed quantitatively in the stomach, jejunum, and ileum. Subsequently, a range of oral contrast dilutions were imaged at varying kVp's in a commercially available CIRS tissue equivalent phantom model. RESULTS: In the retrospective patient study, mean oral contrast density increased significantly in the ileum compared to the jejunum (455.2 and 308.8 HU, respectively, p < 0.01). Similar findings were seen in patients regardless of patients' weight. Mean oral contrast density was higher on lower-energy scans, requiring more window/level adjustment. An oral contrast iodine concentration of 5.82-7.77 mg I/mL most closely approximated a target oral contrast density of 200 HU. CONCLUSIONS: Oral contrast density is strongly influenced by kVp, supporting use of more dilute oral contrast when using lower-kVp techniques.