The spinal muscular atrophy gene product regulates actin dynamics.

Spinal Muscular Atrophy (SMA) is a neuromuscular disease caused by low levels of the Survival of Motoneuron (SMN) protein. SMN interacts with and regulates the actin-binding protein profilin2a, thereby influencing actin dynamics. Dysfunctional actin dynamics caused by SMN loss disrupts neurite outgrowth, axonal pathfinding, and formation of functional synapses in neurons.

Switch-2 determines MgADP-release kinetics and fine-tunes the duty ratio of class-1 myosins.

Though myosins share a structurally conserved motor domain, single amino acid variations of active site elements, including the P-loop, switch-1 and switch-2, which act as nucleotide sensors, can substantially determine the kinetic signature of a myosin, ., to either perform fast movement or enable long-range transport and tension generation. Switch-2 essentially contributes to the ATP hydrolysis reaction and determines product release.

Racial and Ethnic Disparities in COVID-19-Related Stressor Exposure and Adverse Mental Health Outcomes Among Health Care Workers.

Objective: Racial and ethnic disparities in exposure to COVID-19-related stressors, pandemic-related distress, and adverse mental health outcomes were assessed among health care workers in the Bronx, New York, during the first wave of the pandemic.

Methods: The authors analyzed survey data from 992 health care workers using adjusted logistic regression models to assess differential prevalence of outcomes by race/ethnicity and their interactions.

Results: Compared with their White colleagues, Latinx, Black, Asian, and multiracial/other health care workers reported significantly higher exposure to multiple COVID-19-related stressors: redeployment, fear of being sick, lack of autonomy at work, and inadequate access to personal protective equipment.

Survival Outcome in True Carcinoma of Unknown Primary (tCUP) with p16 + Cervical Metastasis.

 Age and lymph node ratio have been attributed as independent predictors for survival and recurrence in carcinoma of unknown primary (CUP).  The purpose of this study was to analyze the prognostic value of p16 overexpression for CUP in the absence of true primary (TP).  The study involved 43 patients who underwent therapeutic lymph node dissection (LND) from 2000 to 2015 after all the diagnostic work up for CUP.

Correction: Franz et al. Unraveling a Force-Generating Allosteric Pathway of Actomyosin Communication Associated with ADP and P Release. . 2021, , 104.

The author wishes to make the following correction to this paper [...

[Little frog in the mouth: a visual diagnosis?].

Ranula, from the Latin "little frog", is a retention cyst filled with saliva in the oral cavity. Simple ranulas most commonly affect the sublingual gland and typically present as a hemispherical bluish cyst on the floor of the mouth, making it a visual diagnosis. A 7-year-old girl presented with a swelling on the underside of the tongue, an uncommon location for a ranula that made diagnostic assignment difficult.

Carcinoma of Unknown Primary (CUP) versus CUP Turned to Primary Carcinoma of the Head and Neck-An Analysis of Diagnostic Methods and the Impact of Primary Tumor on Clinical Outcome.

Background: The purpose of this study was to analyze the value of different diagnostic methods in detecting the primary site and the impact of primary tumors on the clinical outcome of carcinoma of unknown primary (CUP).

Methods: In this multicenter, retrospective study, 124 patients with true CUP (n = 94) and CUP turned to primary carcinoma (n = 30) were included. Patients with evidence of primary site during the clinical examination were excluded a priori.

Unraveling a Force-Generating Allosteric Pathway of Actomyosin Communication Associated with ADP and P Release.

The actomyosin system generates mechanical work with the execution of the power stroke, an ATP-driven, two-step rotational swing of the myosin-neck that occurs post ATP hydrolysis during the transition from weakly to strongly actin-bound myosin states concomitant with P release and prior to ADP dissociation. The activating role of actin on product release and force generation is well documented; however, the communication paths associated with weak-to-strong transitions are poorly characterized. With the aid of mutant analyses based on kinetic investigations and simulations, we identified the W-helix as an important hub coupling the structural changes of switch elements during ATP hydrolysis to temporally controlled interactions with actin that are passed to the central transducer and converter.

Structural and Computational Insights into a Blebbistatin-Bound Myosin•ADP Complex with Characteristics of an ADP-Release Conformation along the Two-Step Myosin Power Stoke.

The motor protein myosin drives a wide range of cellular and muscular functions by generating directed movement and force, fueled through adenosine triphosphate (ATP) hydrolysis. Release of the hydrolysis product adenosine diphosphate (ADP) is a fundamental and regulatory process during force production. However, details about the molecular mechanism accompanying ADP release are scarce due to the lack of representative structures.

A thermophoresis-based biosensor for real-time detection of inorganic phosphate during enzymatic reactions.

Inorganic phosphate (P)-sensing is a key application in many disciplines, and biosensors emerged as powerful analytic tools for use in environmental P monitoring, food quality control, basic research, and medical diagnosis. Current sensing techniques exploit either electrochemical or optical detection approaches for P quantification. Here, by combining the advantages of a biological P-receptor based on the bacterial phosphate binding protein with the principle of thermophoresis, i.

Single-molecule analysis reveals that regulatory light chains fine-tune skeletal myosin II function.

Myosin II is the main force-generating motor during muscle contraction. Myosin II exists as different isoforms that are involved in diverse physiological functions. One outstanding question is whether the myosin heavy chain (MHC) isoforms alone account for these distinct physiological properties.

Profilin2a-phosphorylation as a regulatory mechanism for actin dynamics.

Profilin is a major regulator of actin dynamics in multiple specific processes localized in different cellular compartments. This specificity is not only meditated by its binding to actin but also its interaction with phospholipids such as phosphatidylinositol (4,5)-bisphosphate (PIP ) at the membrane and a plethora of proteins containing poly-L-proline (PLP) stretches. These interactions are fine-tuned by posttranslational modifications such as phosphorylation.

Tracheostomy in bilateral neck dissection: Comparison of three tracheostomy scoring systems.

Objectives: To evaluate whether elective tracheostomy is justified after tumor resection and bilateral neck dissection (ND) and whether application of tracheostomy scoring systems is reliable for planning of postoperative airway management.

Study Design: Retrospective cohort study.

Methods: We retrospectively assessed airway management in 160 patients with head and neck squamous cell carcinomas.

Longitudinal changes in brain structures related to appetitive reactivity and regulation across development.

In the United States over one-third of the population, including children and adolescents, are overweight or obese. Despite the prevalence of obesity, few studies have examined how food cravings and the ability to regulate them change throughout development. Here, we addressed this gap in knowledge by examining structural brain and behavioral changes associated with regulation of craving across development.