When our body fights an infection, the immune system must quickly activate defenses and trigger a beneficial inflammatory response. But it is just as important to resolve that inflammation and return to homeostasis. Macrophages play a key role in this balance: they are cells specialized in phagocytosing, or engulfing, cells that have died due to viral infection and in repairing infection—or inflammation—related tissue damage.

A study conducted at the Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC) and published in Immunity reveals the mechanism by which a signal associated with antiviral and inflammatory responses— type I interferon (IFN-I)—tunes macrophage mitochondria to enhance the clearance of tissue damage and prevent uncontrolled inflammation.

IFN-I is a cytokine that can promote either inflammatory or anti-inflammatory responses, depending on the disease context. It activates a specific inflammatory program known as interferon-stimulated genes (ISGs).

3′UTR shortening in muscle stem cell differentiation.

Global changes in alternative polyadenylation (APA) leads to alterations in 3′ untranslated region (3′UTR) length and is accompanied by cell differentiation. However, APA role in muscle stem cell differentiation remain unclear.

The authors show that preferential 3′UTR shortening during stem cell differentiation occurs via CFI-mediated APA regulation.

They also demonstrate that 3′UTR shortening is a general strategy to escape repression by myomiRs.

This study reveals a tendency toward 3′UTR shortening, which alleviates miRNA repression of mRNAs critical for differentiation, ensuring efficient muscle differentiation and regeneration.

The authors used Matr3 expression to demonstrate the APA and miR-1/206 antagonistic role in myogenesis and they show that mutating the proximal Matr3 polyadenylation site in mice impairs muscle regeneration. sciencenewshighlights ScienceMission https://sciencemission.com/3%E2%80%B2UTR-shortening-alleviates-miRNA-repression

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About 1 in 7 users (14.6%) of injectable GLP-1 receptor agonists (RAs) have taken or are taking them at lower doses than those approved by the FDA, and many decided to do so without clinician input, a new survey found.

The most common reasons for GLP-1 RA microdosing are to manage tolerability, save money, and transition from weight loss to weight maintenance, according to the survey by Evidation, a California-based company that gathers healthcare information directly from members via its app.

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The situation was far different among respondents who were actively microdosing — only 39.8% of them said they got their medication from their current healthcare clinician. Almost 24% reported getting their GLP-1 RA from a telehealth service. Less common sources included med spas, weight-loss clinics and directly from the manufacturer.

Telemedicine services typically offer lower-cost compounded versions of GLP-1 RAs, making them an attractive option for patients, noted an article in Medscape Medical News.

When asked about their most trusted source of information on microdosing, a larger percentage of GLP-1 RA users answered social media (26.8%) and online research (24.4%) than answered their healthcare clinician (20.3%).

By Nina Bai

A study led by Stanford Medicine found that the earliest sign of bladder cancer — blood in the urine — may be invisible to people who are colorblind, increasing their risk of dying from the disease.

Here, Deepak A. Rao & team use mass cytometry immune profiling to identify T cell features in pre-treatment blood samples from patients that are associated with irAEs after ICI therapy.

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¹Division of Rheumatology, Inflammation, Immunity, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts, USA.

²Division of Rheumatology, Hospital for Special Surgery and Weill Cornell Medicine, New York, New York, USA.

³Memorial Sloan Kettering Center and Weill Cornell Medical College, New York, New York, USA.