Retrospective Investigation and Research on Fall Events Among Hospitalized Patients in the Rehabilitation Department.

Objective: We investigated the clinical characteristics, fall outcomes, and related factors of falls in patients who were hospitalized in the rehabilitation department, and explored strategies to reduce the incidence of falls and prevent falls in patients.

Methods: Data from 60 patients who fell in the rehabilitation department between 2016 and 2021 were analyzed for clinical characteristics, associated factors, incidence of falls, injuries, and patient demographics. Under the random stratified sampling method, 60 patients who did not fall during the same period were selected as the control group, and relevant data was collected.

Extracellular release in the quality control of the mammalian mitochondria.

Mammalian cells release a wealth of materials to their surroundings. Emerging data suggest these materials can even be mitochondria with perturbed morphology and aberrant function. These dysfunctional mitochondria are removed by migrating cells through membrane shedding.

Nanoscale details of mitochondrial constriction revealed by cryoelectron tomography.

Mitochondria adapt to changing cellular environments, stress stimuli, and metabolic demands through dramatic morphological remodeling of their shape, and thus function. Such mitochondrial dynamics is often dependent on cytoskeletal filament interactions. However, the precise organization of these filamentous assemblies remains speculative.

Monitoring Stub1-Mediated Pexophagy.

Mammalian cells can turn over peroxisomes through Stub1-mediated pexophagy. The pathway potentially permits cellular control of the quantity and quality of peroxisomes. During this process, heat shock protein 70 and the ubiquitin E3 ligase, Stub1, translocate onto peroxisomes to be turned over to initiate pexophagy.

Parkin coordinates mitochondrial lipid remodeling to execute mitophagy.

Autophagy has emerged as the prime machinery for implementing organelle quality control. In the context of mitophagy, the ubiquitin E3 ligase Parkin tags impaired mitochondria with ubiquitin to activate autophagic degradation. Although ubiquitination is essential for mitophagy, it is unclear how ubiquitinated mitochondria activate autophagosome assembly locally to ensure efficient destruction.

Golgi quality control and autophagy.

Organelles can easily be disrupted by intracellular and extracellular factors. Studies on ER and mitochondria indicate that a wide range of responses are elicited upon organelle disruption. One response thought to be of particular importance is autophagy.

Enhanced enzymatic production of cholesteryl 6'-acylglucoside impairs lysosomal degradation for the intracellular survival of Helicobacter pylori.

Background: During autophagy defense against invading microbes, certain lipid types are indispensable for generating specialized membrane-bound organelles. The lipid composition of autophagosomes remains obscure, as does the issue of how specific lipids and lipid-associated enzymes participate in autophagosome formation and maturation. Helicobacter pylori is auxotrophic for cholesterol and converts cholesterol to cholesteryl glucoside derivatives, including cholesteryl 6'-O-acyl-α-D-glucoside (CAG).

A cryo-electron tomography workflow reveals protrusion-mediated shedding on injured plasma membrane.

Cryo-electron tomography (cryo-ET) provides structural context to molecular mechanisms underlying biological processes. Although straightforward to implement for studying stable macromolecular complexes, using it to locate short-lived structures and events can be impractical. A combination of live-cell microscopy, correlative light and electron microscopy, and cryo-ET will alleviate this issue.

Hsc70/Stub1 promotes the removal of individual oxidatively stressed peroxisomes.

Peroxisomes perform beta-oxidation of branched and very-long chain fatty acids, which leads to the formation of reactive oxygen species (ROS) within the peroxisomal lumen. Peroxisomes are therefore prone to ROS-mediated damages. Here, using light to specifically and acutely induce ROS formation within the peroxisomal lumen, we find that cells individually remove ROS-stressed peroxisomes through ubiquitin-dependent pexophagy.

Vesicular transport mediates the uptake of cytoplasmic proteins into mitochondria in Drosophila melanogaster.

Mitochondrial aging, which results in mitochondrial dysfunction, is strongly linked to many age-related diseases. Aging is associated with mitochondrial enlargement and transport of cytosolic proteins into mitochondria. The underlying homeostatic mechanisms that regulate mitochondrial morphology and function, and their breakdown during aging, remain unclear.

Correction: Regulation of ATG4B Stability by RNF5 Limits Basal Levels of Autophagy and Influences Susceptibility to Bacterial Infection.

[This corrects the article DOI: 10.1371/journal.pgen.

Intracellular galectins control cellular responses commensurate with cell surface carbohydrate composition.

Galectins are β-galactoside-binding animal lectins primarily found in the cytosol, while their carbohydrate ligands are mainly distributed in the extracellular space. Cytosolic galectins are anticipated to accumulate on damaged endocytic vesicles through binding to glycans initially displayed on the cell surface and subsequently located in the lumen of the vesicles, and this can be followed by cellular responses. To facilitate elucidation of the mechanism underlying this process, we adopted a model system involving induction of endocytic vesicle damage with light that targets the endocytosed amphiphilic photosensitizer disulfonated aluminum phthalocyanine.

Omegasome-proximal PtdIns(4,5)P couples F-actin mediated mitoaggregate disassembly with autophagosome formation during mitophagy.

Cells govern their homeostasis through autophagy by sequestering substrates, ranging from proteins to aggregates and organelles, into autophagosomes for lysosomal degradation. In these processes cells need to coordinate between substrate remodeling and autophagosome formation for efficient engulfment. We found that in Parkin-mediated mitophagy, mitochondria to be turned over first become grape-like mitoaggregates, followed by their disassembly into smaller pieces via the actinomyosin system.

Srv2 Is a Pro-fission Factor that Modulates Yeast Mitochondrial Morphology and Respiration by Regulating Actin Assembly.

Dynamic processes such as fusion, fission, and trafficking are important in the regulation of cellular organelles, with an abundant literature focused on mitochondria. Mitochondrial dynamics not only help shape its network within cells but also are involved in the modulation of respiration and integrity. Disruptions of mitochondrial dynamics are associated with neurodegenerative disorders.

Triggering Mitophagy with Photosensitizers.

One can utilize light illumination to stimulate mitochondrial reactive oxygen species production through the use of mitochondria-specific photosensitizers. By proper tuning of the light dosage, the methodology permits probing of a multitude of mitochondrial damage responses, including mitophagy. This light-controllable trick offers unique opportunities for the investigation of mitophagy-one can spatiotemporally define mitochondrial damage, alter the number of impaired mitochondria, as well as modulate the severity of the mitochondrial injury.

Staining of Lipid Droplets with Monodansylpentane.

Monodansylpentane (MDH) is a fluorophore that displays selective labeling of lipid droplets (LDs). The dye preferentially segregates into the neutral lipid cores of LDs and emits blue fluorescence, compatible with the simultaneous use of green and red fluorescent reporters in multi-color live-cell imaging. MDH can be used for visualizing LDs not only in cell cultures, but also in fixed tissues such as the fat body and ovaries from Drosophila.

Optogenetic probing of mitochondrial damage responses.

It is now possible to functionally impair mitochondria through light illumination with high specificity. These optogenetic tools permit precise control on the timing, location, and extent of mitochondrial damage within a cell population with subcellular resolution, allowing quantitative probing of the various types of mitochondrial damage responses within cells. This approach can generally be extended toward the probing of other organelle damage responses.

Triggering mitophagy with far-red fluorescent photosensitizers.

Cells identify defective mitochondria and eliminate them through mitophagy: this allows cells to rid themselves of unwanted stress to maintain health and avoid the activation of cell death. One approach to experimentally investigate mitophagy is through the use of mitochondrial photosensitizers, which when coupled with light allows one to precisely control mitochondrial damage with spatial and temporal precision. Here we report three far-red fluorophores that can be used as robust mitochondrial photosensitizers to initiate mitophagy.

Bit-by-bit autophagic removal of parkin-labelled mitochondria.

Eukaryotic cells maintain mitochondrial integrity through mitophagy, an autophagic process by which dysfunctional mitochondria are selectively sequestered into double-layered membrane structures, termed phagophores, and delivered to lysosomes for degradation. Here we show that small fragments of parkin-labelled mitochondria at omegasome-marked sites are engulfed by autophagic membranes one at a time. Using a light-activation scheme to impair long mitochondrial tubules, we demonstrate that sites undergoing bit-by-bit mitophagy display preferential ubiquitination, and are situated where parkin-labelled mitochondrial tubules and endoplasmic reticulum intersect.

Spatiotemporally controlled induction of autophagy-mediated lysosome turnover.

Lysosomes are the major degradative compartments within cells, harbouring a wide variety of hydrolytic enzymes within their lumen. Release of lysosomal hydrolases from lysosomes into the cell cytoplasm results in cell death. Here we report that damaged lysosomes undergo autophagic turnover.

Regulation of ATG4B stability by RNF5 limits basal levels of autophagy and influences susceptibility to bacterial infection.

Autophagy is the mechanism by which cytoplasmic components and organelles are degraded by the lysosomal machinery in response to diverse stimuli including nutrient deprivation, intracellular pathogens, and multiple forms of cellular stress. Here, we show that the membrane-associated E3 ligase RNF5 regulates basal levels of autophagy by controlling the stability of a select pool of the cysteine protease ATG4B. RNF5 controls the membranal fraction of ATG4B and limits LC3 (ATG8) processing, which is required for phagophore and autophagosome formation.

Guidelines for the use and interpretation of assays for monitoring autophagy.

In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding.