Upper Gastrointestinal Bleeding Secondary to Sodium Polystyrene Sulfonate Use: A Rare Adverse Effect of Commonly Prescribed Treatment.

We report a case of a 62-year-old man who was brought in by emergency medical services after a fall and change in mental status. He was found to have severe hyperkalemia, acute kidney injury, and rhabdomyolysis. The hyperkalemia was treated with sodium polystyrene sulfonate (SPS). During hospitalization, he witnessed having black tarry stools along with a significant drop in hemoglobin. Endoscopic evaluation demonstrated nonbleeding large diffuse gastric ulcers with stigmata of recent bleeding, and ulcer biopsy revealed findings consistent with SPS-induced gastric ulceration. No other source of bleeding was localized, suggesting acute upper gastrointestinal bleeding due to SPS mucosal injury.

Signet Ring Cell Carcinoma Presenting as a Necrotic Duodenocolic Fistulizing Mass.

A 79-year-old female was referred for endoscopic evaluation after a positive fecal occult blood test. There was a long-standing history of iron deficiency anemia, weight loss with intermittent touts of intractable vomiting, and nausea. Esophagogastroduodenoscopy revealed a secondary lumen between the duodenum and transverse colon with necrotic mucosa and a blind opening. Subsequent colonoscopy revealed similar necrotic mucosa at the transverse colon and fistula formation with communication into the duodenum. Signet ring cell carcinoma (SRCC) was evident in histologic analysis. SRCC carries a poorer prognosis than other variants of colorectal carcinoma (CRC). Proposed mechanisms of increased mucin production can lead to mucosal wall destruction and have profound manifestations, such as in our patient with duodenocolic fistula.

A Review of Crucial Radiological Investigations in the Management of COVID-19 Cases.

Chest X-ray, chest CT, and lung ultrasound are the most common radiological interventions used in the diagnosis and management of coronavirus disease 2019 (COVID-19) patients. The purpose of this literature review, which was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, is to determine which radiological investigation is crucial for that purpose. PubMed, Medline, American Journal of Radiology (AJR), Public Library of Science (PLOS), Elsevier, National Center for Biotechnology Information (NCBI), and ScienceDirect were explored. Seventy-two articles were reviewed for potential inclusion, including 50 discussing chest CT, 15 discussing chest X-ray, five discussing lung ultrasound, and two discussing COVID-19 epidemiology. The reported sensitivities and specificities for chest CT ranged from 64 to 98% and 25 to 88%, respectively. The reported sensitivities and specificities for chest X-rays ranged from 33 to 89% and 11.1 to 88.9%, respectively. The reported sensitivities and specificities for lung ultrasound ranged from 93 to 96.8% and 21.3 to 95%, respectively. The most common findings on chest CT include ground glass opacities and consolidation. The most common findings on chest X-rays include opacities, consolidation, and pleural effusion. The data indicate that chest CT is the most effective radiological tool for the diagnosis and management of COVID-19 patients. The authors support the continued use of reverse transcription polymerase chain reaction (RT-PCR), along with physical examination and contact history, for such diagnosis. Chest CT could be more appropriate in emergency situations when quick triage of patients is necessary before RT-PCR results are available. CT can also be used to visualize the progression of COVID-19 pneumonia and to identify potential false positive RT-PCR results. Chest X-ray and lung ultrasound are acceptable in situations where chest CT is unavailable or contraindicated.

Myh11 Lineage Corneal Endothelial Cells and ASCs Populate Corneal Endothelium.

Purpose: To establish Myh11 as a marker of a subset of corneal endothelial cells (CECs), and to demonstrate the feasibility of restoring the corneal endothelium with Myh11-lineage (Myh11-Lin[+]) adipose-derived stromal cells (ASCs). Methods: Intraperitoneal administration of tamoxifen and (Z)-4-hydroxytamoxifen eyedrops were used to trace the lineage of Myh11-expressing cells with the Myh11-Cre-ERT2-flox-tdTomato mouse model. Immunostaining and Western blot characterized marker expression and spatial distribution of Myh11-Lin(+) cells in the cornea, and administration of 5-ethynyl-2'-deoxyuridine labeled proliferating cells. ASCs were isolated from epididymal adipose Myh11+ mural cells and treated with cornea differentiation media to evaluate corneal endothelial differentiation potential. Differentiated ASCs were injected into the anterior chamber to test for incorporation into corneal endothelium following scratch injury. Results: A subset of CECs express Myh11, a marker previously thought restricted to only mural cells. Myh11-Lin(+) CECs marked a stable subpopulation of cells in the cornea endothelium. Myh11-Lin(+) ASCs undergo CEC differentiation in vitro and incorporate into injured corneal endothelium. Conclusions: Dystrophy and dysfunction of the corneal endothelium accounts for almost half of all corneal transplants, the maintenance of the cornea endothelium is poorly understood, and there are a lack of mouse models to study specific CEC populations. We establish a mouse model that can trace the cell fate of a subpopulation of CECs based on Myh11 expression. A subset of ASCs that share this Myh11 transcriptional lineage are capable of differentiating into CECs that can incorporate into injured corneal endothelium, revealing a potential cell source for creating engineered transplant material.