Drosophila Smad2 degradation occurs independently of linker phosphorylations.

TGF-ß signals are important for proliferation, differentiation, and cell fate determination during embryonic development and tissue homeostasis in adults. Drosophila Activin/TGF-ß signals are transduced intracellularly when its transcription factor dSmad2 (also called Smad on X or Smox) is C-terminally phosphorylated by pathway receptors. Recently, it has been shown that receptor-activated dSmad2 undergoes bulk degradation, however, the mechanism of how this occurs is unknown. Here we investigated if two putative linker phosphorylation sites are involved in dSmad2 degradation. We demonstrate that degradation of activated-dSmad2 occurs independently of threonine phosphorylation at linker sites 252 and 277. We also show that dSmad2 degradation is not carried out by cellular proteasomes.

Histologically Remarkable Eosinophilic Esophagitis Responsive to Dupilumab in a Gastrostomy Tube-Dependent Pediatric Patient on Amino Acid Formula.

Eosinophilic esophagitis (EoE), an eosinophil predominant, TH2-mediated condition increasing in prevalence in pediatric and adult populations, is typically treated with dietary manipulations to avoid triggering antigens. However, identifying specific dietary causes remains a persistent challenge, and restrictive diets are burdensome. Total dietary modification using amino acid-based formula does not always produce symptomatic or histologic resolution, suggesting that exposure to ingested aeroallergens drives their disease. EoE patients demonstrate symptomatic exacerbation from July to September correlating with higher grass and ragweed pollen counts. We present a 7-year-old tracheostomy- and gastrostomy-dependent girl who was found on surveillance endoscopy to have profound eosinophilic infiltration throughout the esophagus with inflammatory changes including basal cell hyperplasia on histology. She responded partially to topical corticosteroid therapy with fluticasone and had complete resolution of esophageal eosinophilic infiltrate with subcutaneous dupilumab.

Persistent SARS-CoV-2 Nucleocapsid Protein Presence in the Intestinal Epithelium of a Pediatric Patient 3 Months After Acute Infection.

In addition to the severe impact of acute respiratory disease during the SARS-CoV-2 pandemic, the issue of "Long COVID" illness has impacted large numbers of patients following the initial infection. Wide ranges of Long Covid incidence have been reported, ranging from 30 to 87%. Long COVID has a variety of clinical manifestations, including gastrointestinal symptoms. Here, we report a case of persistent abdominal pain, 3 months following a SARS-CoV-2 diagnosis, associated with chronic colonic inflammation and the presence of mucosal SARS-CoV-2 virions.

Dyslipidemia Is a Major Factor in Stem Cell Damage Induced by Uncontrolled Long-Term Type 2 Diabetes and Obesity in the Rat, as Suggested by the Effects on Stem Cell Culture.

BACKGROUND: Previous work showed that muscle-derived stem cells (MDSCs) exposed long-term to the milieu of uncontrolled type 2 diabetes (UC-T2D) in male obese Zucker (OZ) rats, were unable to correct the associated erectile dysfunction and the underlying histopathology when implanted into the corpora cavernosa, and were also imprinted with a noxious gene global transcriptional signature (gene-GTS), suggesting that this may interfere with their use as autografts in stem cell therapy. AIM: To ascertain the respective contributions of dyslipidemia and hyperglycemia to this MDSC damage, clarify its mechanism, and design a bioassay to identify the damaged stem cells. METHODS: Early diabetes MDSCs and late diabetes MDSCs were respectively isolated from nearly normal young OZ rats and moderately hyperglycemic and severely dyslipidemic/obese aged rats with erectile dysfunction. Monolayer cultures of early diabetic MDSCs were incubated 4 days in DMEM/10% fetal calf serum + or - aged OZ or lean Zucker serum from non-diabetic lean Zucker rats (0.5-5%) or with soluble palmitic acid (PA) (0.5-2 mM), cholesterol (CHOL) (50-400 mg/dL), or glucose (10-25 mM). MAIN OUTCOME MEASURE: Fat infiltration was estimated by Oil red O, apoptosis by TUNEL, protein expression by Western blots, and gene-GTS and microRNA (miR)-GTS were determined in these stem cells' RNA. RESULTS: Aged OZ serum caused fat infiltration, apoptosis, myostatin overexpression, and impaired differentiation. Some of these changes, and also a proliferation decrease occurred with PA and CHOL. The gene-GTS changes by OZ serum did not resemble the in vivo changes, but some occurred with PA and CHOL. The miR-GTS changes by OZ serum, PA, and CHOL resembled most of the in vivo changes. Hyperglycemia did not replicate most alterations. CLINICAL IMPLICATIONS: MDSCs may be damaged in long-term UC-T2D/obese patients and be ineffective in autologous human stem cell therapy, which may be prevented by excluding the damaged MDSCs. STRENGTH & LIMITATIONS: The in vitro test of MDSCs is innovative and fast to define dyslipidemic factors inducing stem cell damage, its mechanism, prevention, and counteraction. Confirmation is required in other T2D/obesity rat models and stem cells (including human), as well as miR-GTS biomarker validation as a stem cell damage biomarker. CONCLUSION: Serum from long-term UC-T2D/obese rats or dyslipidemic factors induces a noxious phenotype and miR-GTS on normal MDSCs, which may lead in vivo to the repair inefficacy of late diabetic MDSCs. This suggests that autograft therapy with MDSCs in long-term UT-T2D obese patients may be ineffective, albeit this may be predictable by prior stem cell miR-GTS tests. Masouminia M, Gelfand R, Kovanecz I, et al. Dyslipidemia Is a Major Factor in Stem Cell Damage Induced by Uncontrolled Long-Term Type 2 Diabetes and Obesity in the Rat, as Suggested by the Effects on Stem Cell Culture. J Sex Med 2018;15:1678-1697.