Viscoelastic Characteristics in Mouse Model of Hepatic Steatosis With Inflammation by Kelvin-Voigt Fractional Derivative Modeling.

OBJECTIVE: The aim of the work described here was to measure the characteristics of viscoelasticity and fluidity in a mouse model of hepatic steatosis and inflammation using a nano-indentation test and the Kelvin-Voigt fractional derivative (KVFD) model and to explore the viscoelasticity and fluidity characteristics in mice with different degrees of hepatic steatosis with inflammation. METHODS: Twenty-five ApoE mice were randomly divided into an experimental high-fat diet group (n = 15) and an ordinary-food control group (n = 10), then subdivided into four subgroups based on pathological degree of hepatic steatosis: S0 (normal), S1 (mild), S2 (moderate) and S3 (severe). The 25 liver specimens from these mice were evaluated by a slope-keeping relaxation nano-indentation test. RESULTS: Elasticity (E0) was significantly higher in the S3 group than in the S1 and S2 groups, while fluidity (α) and viscosity (τ) were significantly lower in S3 than in S1 and S2 (all p values < 0.05). The following cutoff values for the diagnosis of hepatic steatosis >33% with inflammation were also determined: E0 > 85.01 Pa (area under the curve [AUC]: 0.917, 95% confidence interval [CI]: 0.735-0.989), α ≤ 0.38 (AUC: 0.885, 95% CI: 0.695-0.977),\ and τ ≤ 3.92 (AUC: 0.813, 95% CI: 0.607-0.939). CONCLUSION: Increases in the degree of hepatic steatosis with inflammation in mice paralleled gradual increases in the stiffness of the liver and gradual decreases in the fluidity and viscosity of the liver.

Retraction: A Rare Presentation of Isolated IgM Deficiency in a 28-Year-Old Male: A Case Report.

[This retracts the article DOI: 10.7759/cureus.29931.].

A Rare Presentation of Isolated IgM Deficiency in a 28-Year-Old Male: A Case Report.

Immunoglobulin M (IgM) plays a regulatory role in subsequent immune response development, thereby accelerating the production of immunoglobulin G (IgG) with high affinity. Selective IgM deficiency (SIGMD) is a rare immune disorder that has been reported in association with serious infections, such as bacteremia. Patients commonly present with infections, atopy, septicemia, splenomegaly, neoplasia, and other autoimmune disorders. Treatment modalities and recommendations range from careful monitoring to vaccinations, aggressive management of respiratory infections, preventive and therapeutic antibiotics, and intravenous immunoglobulin (IVIG). There is insufficient information to generalize patients' prognosis with selective IgM deficiency due to the small number of patients and lack of prospective studies. We hereby present the case of a 28-year-old male with multiple recurrent boils, cellulitis, and osteomyelitis who has been diagnosed with selective IgM deficiency and is being treated with IVIG. This case report highlights the diagnostic evaluation and therapeutic care of patients with SIGMD and the need for follow-up.