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Molecular Imaging and Radionuclide... Jun 2024A 52-year-old female patient with metastatic breast cancer receiving denosumab for 7 years presented with marked diffuse tracer uptake in the mandible on...
A 52-year-old female patient with metastatic breast cancer receiving denosumab for 7 years presented with marked diffuse tracer uptake in the mandible on Tc-99m-methylene diphosphonate bone scintigraphy, resembling the Lincoln sign. A diagnosis of medication-related osteonecrosis of the jaw (MRONJ) was confirmed, leading to immediate discontinuation of denosumab. Conservative therapy, including limited debridement and oral rinses, was initiated. MRONJ, a potential complication of bone-modifying agents, is more prevalent in advanced malignancy cases. The Lincoln sign has not been previously reported in MRONJ, emphasizing its consideration in cancer patients undergoing bone-modifying agent treatment.
PubMed: 38949491
DOI: 10.4274/mirt.galenos.2023.37980 -
Journal of Visualized Experiments : JoVE Jun 2024Sepsis is a major cause of in-hospital deaths. Improvements in treatment result in a greater number of sepsis survivors. Approximately 75% of the survivors develop...
Sepsis is a major cause of in-hospital deaths. Improvements in treatment result in a greater number of sepsis survivors. Approximately 75% of the survivors develop muscle weakness and atrophy, increasing the incidence of hospital readmissions and mortality. However, the available preclinical models of sepsis do not address skeletal muscle disuse, a key component for the development of sepsis-induced myopathy. Our objective in this protocol is to provide a step-by-step guideline for a mouse model that reproduces the clinical setting experienced by a bedridden septic patient. Male C57Bl/6 mice were used to develop this model. Mice underwent cecal ligation and puncture (CLP) to induce sepsis. Four days post-CLP, mice were subjected to hindlimb suspension (HLS) for seven days. Results were compared with sham-matched surgeries and/or animals with normal ambulation (NA). Muscles were dissected for in vitro muscle mechanics and morphological assessments. The model results in marked muscle atrophy and weakness, a similar phenotype observed in septic patients. The model represents a platform for testing potential therapeutic strategies for the mitigation of sepsis-induced myopathy.
Topics: Animals; Sepsis; Mice; Disease Models, Animal; Male; Mice, Inbred C57BL; Muscular Diseases; Muscular Atrophy; Muscle, Skeletal; Hindlimb Suspension
PubMed: 38949310
DOI: 10.3791/66685 -
MBio Jul 2024Protein kinases are critical regulatory proteins in both prokaryotes and eukaryotes. Accordingly, protein kinases represent a common drug target for a wide range of...
Protein kinases are critical regulatory proteins in both prokaryotes and eukaryotes. Accordingly, protein kinases represent a common drug target for a wide range of human diseases. Therefore, understanding protein kinase function in human pathogens such as the fungus is likely to extend our knowledge of its pathobiology and identify new potential therapies. To facilitate the study of protein kinases, we constructed a library of 99 non-essential protein kinase homozygous deletion mutants marked with barcodes in the widely used SN genetic background. Here, we describe the construction of this library and the characterization of the competitive fitness of the protein kinase mutants under 11 different growth and stress conditions. We also screened the library for protein kinase mutants with altered filamentation and biofilm formation, two critical virulence traits of . An extensive network of protein kinases governs these virulence traits in a manner highly dependent on the specific environmental conditions. Studies on specific protein kinases revealed that (i) the cell wall integrity MAPK pathway plays a condition-dependent role in filament initiation and elongation; (ii) the hyper-osmolar glycerol MAPK pathway is required for both filamentation and biofilm formation, particularly in the setting of catheter infection; and (iii) Sok1 is dispensable for filamentation in hypoxic environments at the basal level of a biofilm but is required for filamentation in normoxia. In addition to providing a new genetic resource for the community, these observations emphasize the environmentally contingent function of protein kinases.IMPORTANCE is one of the most common causes of fungal disease in humans for which new therapies are needed. Protein kinases are key regulatory proteins and are increasingly targeted by drugs for the treatment of a wide range of diseases. Understanding protein kinase function in pathogenesis may facilitate the development of new antifungal drugs. Here, we describe a new library of 99 protein kinase deletion mutants to facilitate the study of protein kinases. Furthermore, we show that the function of protein kinases in two virulence-related processes, filamentation and biofilm formation, is dependent on the specific environmental conditions.
PubMed: 38949302
DOI: 10.1128/mbio.01249-24 -
Clinical and Translational Science Jul 2024Activation of receptor-interacting protein kinase 1 (RIPK1), a broadly expressed serine/threonine protein kinase, by pro-inflammatory cytokines and pathogens can result... (Randomized Controlled Trial)
Randomized Controlled Trial
Activation of receptor-interacting protein kinase 1 (RIPK1), a broadly expressed serine/threonine protein kinase, by pro-inflammatory cytokines and pathogens can result in apoptosis, necroptosis, or inflammation. RIPK1 inhibition has been shown to reduce inflammation and cell damage in preclinical studies and may have therapeutic potential for degenerative and inflammatory diseases. SIR2446 is a potent and selective novel small molecule RIPK1 kinase inhibitor. This phase I, randomized, double-blind, placebo-controlled study in Australia (ACTRN12621001621808) evaluated the safety (primary objective), pharmacokinetics, and pharmacodynamics of single (3-600 mg) and multiple (5-400 mg for 10 days) ascending oral doses of SIR2446M (SIR2446 magnesium salt form) in healthy adults from Nov 24, 2021, until May 01, 2023. All treatment-emergent adverse events (TEAEs) were mild/moderate. The most reported TEAEs were vascular access site pain, headache, and rash morbilliform. SIR2446M plasma half-lives ranged from 11 to 19 h and there were no major deviations from dose proportionality for maximum concentration and area under the curve across doses. Renal excretion of unchanged SIR2446 was minimal. No marked accumulation was observed (mean accumulation ratio, 1.2-1.6) after multiple daily doses. A high-fat meal mildly reduced the exposure but was not considered clinically significant. SIR2446M had a rapid and sustained inhibitory effect on the activity of RIPK1, with an overall 90% target engagement at repeated doses ranging from 30 to 400 mg in peripheral blood mononuclear cells ex vivo stimulated to undergo necroptosis. The favorable safety, pharmacokinetic, and pharmacodynamic profile of SIR2446M in healthy participants supports its further clinical development in patients with degenerative and inflammatory diseases.
Topics: Humans; Adult; Male; Double-Blind Method; Female; Healthy Volunteers; Receptor-Interacting Protein Serine-Threonine Kinases; Middle Aged; Young Adult; Dose-Response Relationship, Drug; Protein Kinase Inhibitors; Administration, Oral; Adolescent; Drug Administration Schedule
PubMed: 38949195
DOI: 10.1111/cts.13857 -
Journal of Medical Virology Jul 2024Antiviral signaling, immune response and cell metabolism are dysregulated by SARS-CoV-2, the causative agent of COVID-19. Here, we show that SARS-CoV-2 accessory...
Antiviral signaling, immune response and cell metabolism are dysregulated by SARS-CoV-2, the causative agent of COVID-19. Here, we show that SARS-CoV-2 accessory proteins ORF3a, ORF9b, ORF9c and ORF10 induce a significant mitochondrial and metabolic reprogramming in A549 lung epithelial cells. While ORF9b, ORF9c and ORF10 induced largely overlapping transcriptomes, ORF3a induced a distinct transcriptome, including the downregulation of numerous genes with critical roles in mitochondrial function and morphology. On the other hand, all four ORFs altered mitochondrial dynamics and function, but only ORF3a and ORF9c induced a marked alteration in mitochondrial cristae structure. Genome-Scale Metabolic Models identified both metabolic flux reprogramming features both shared across all accessory proteins and specific for each accessory protein. Notably, a downregulated amino acid metabolism was observed in ORF9b, ORF9c and ORF10, while an upregulated lipid metabolism was distinctly induced by ORF3a. These findings reveal metabolic dependencies and vulnerabilities prompted by SARS-CoV-2 accessory proteins that may be exploited to identify new targets for intervention.
Topics: Humans; SARS-CoV-2; Mitochondria; COVID-19; A549 Cells; Viral Regulatory and Accessory Proteins; Transcriptome; Open Reading Frames; Viral Proteins; Viroporin Proteins
PubMed: 38949191
DOI: 10.1002/jmv.29752 -
BioRxiv : the Preprint Server For... Jun 2024Inhibitory control is a crucial cognitive-control ability for behavioral flexibility that has been extensively investigated through action-stopping tasks. Multiple...
UNLABELLED
Inhibitory control is a crucial cognitive-control ability for behavioral flexibility that has been extensively investigated through action-stopping tasks. Multiple neurophysiological features have been proposed to represent 'signatures' of inhibitory control during action-stopping, though the processes signified by these signatures are still controversially discussed. The present study aimed to disentangle these processes by comparing simple stopping situations with those in which additional action revisions were needed. Three experiments in female and male humans were performed to characterize the neurophysiological dynamics involved in action-stopping and - changing, with hypotheses derived from recently developed two-stage 'pause-then-cancel' models of inhibitory control. Both stopping and revising an action triggered an early broad 'pause'-process, marked by frontal EEG β-bursts and non-selective suppression of corticospinal excitability. However, partial-EMG responses showed that motor activity was only partially inhibited by this 'pause', and that this activity can be further modulated during action-revision. In line with two-stage models of inhibitory control, subsequent frontocentral EEG activity after this initial 'pause' selectively scaled depending on the required action revisions, with more activity observed for more complex revisions. This demonstrates the presence of a selective, effector-specific 'retune' phase as the second process involved in action-stopping and -revision. Together, these findings show that inhibitory control is implemented over an extended period of time and in at least two phases. We are further able to align the most commonly proposed neurophysiological signatures to these phases and show that they are differentially modulated by the complexity of action-revision.
SIGNIFICANCE STATEMENT
Inhibitory control is one of the most important control processes by which humans can regulate their behavior. Multiple neurophysiological signatures have been proposed to reflect inhibitory control. However, these play out on different time scales and appear to reflect different aspects of cognitive control, which are controversially debated.Recent two-stage models of inhibitory control have proposed that two phases implement the revisions of actions: 'pause' and 'retune'. Here, we provide the first empirical evidence for this proposition: Action revisions engendered a common initial low-latency 'pause', during which motor activity is broadly suppressed. Later activity, however, distinguishes between simple stopping of actions and more complex action revisions. These findings provide novel insights into the sequential dynamics of human action control.
PubMed: 38948849
DOI: 10.1101/2024.06.18.597172 -
BioRxiv : the Preprint Server For... Jun 2024Organismal aging is marked by decline in cellular function and anatomy, ultimately resulting in death. To inform our understanding of the mechanisms underlying this...
Organismal aging is marked by decline in cellular function and anatomy, ultimately resulting in death. To inform our understanding of the mechanisms underlying this degeneration, we performed standard RNA sequencing and Nanopore direct RNA sequencing over an adult time course in Long reads allowed for identification of hundreds of novel isoforms and age-associated differential isoform accumulation, resulting from alternative splicing and terminal exon choice. Genome-wide analysis reveals a decline in RNA processing fidelity and a rise in inosine and pseudouridine editing events in transcripts from older animals. In this first map of pseudouridine modifications for , we find that they largely reside in coding sequences and that the number of genes with this modification increases with age. Collectively, this analysis discovers transcriptomic signatures associated with age and is a valuable resource to understand the many processes that dictate altered gene expression patterns and post-transcriptional regulation in aging.
PubMed: 38948813
DOI: 10.1101/2024.06.18.599640 -
BioRxiv : the Preprint Server For... Jun 2024Duchenne muscular dystrophy (DMD) is marked by the genetic deficiency of the dystrophin protein in striated muscle whose consequence is a cascade of cellular changes...
Duchenne muscular dystrophy (DMD) is marked by the genetic deficiency of the dystrophin protein in striated muscle whose consequence is a cascade of cellular changes that predispose the susceptibility to contraction injury central to DMD pathology. Recent evidence identified the proliferation of microtubules enriched in post-translationally modified tubulin as a consequence of dystrophins absence that increases the passive mechanics of the muscle fiber and the excess mechanotransduction elicited reactive oxygen species and calcium signals that promote contraction injury. Motivated by evidence that acutely normalizing the disease microtubule alterations reduced contraction injury in murine DMD muscle ( ), here we sought the direct impact of these microtubule alterations independent of dystrophins absence and the multitude of other changes consequent to dystrophic disease. To this end we used acute pharmacologic (epithiolone-D, EpoD; 4 hours) or genetic (vashohibin-2 and small vasohibin binding protein overexpression via AAV9; 2 weeks) strategies to effectively model the proliferation of detyrosination enriched microtubules in the muscle. Quantifying nerve evoked plantarflexor function we find no alteration in peak torque nor contraction kinetics in WT mice modeling these DMD relevant MT alterations. Quantifying the susceptibility to eccentric contraction injury we show EpoD treatment proffered a small but significant protection from contraction injury while VASH/SVBP had no discernable impact. We conclude that the disease dependent MT alterations act in concert with additional cellular changes to predispose contraction injury in DMD.
PubMed: 38948772
DOI: 10.1101/2024.06.19.599775 -
mutation induces tumor cell-intrinsic defects in enhancer landscape and resistance to immunotherapy.BioRxiv : the Preprint Server For... Jun 2024Cancer genomic studies have identified frequent alterations in components of the SWI/SNF (SWItch/Sucrose Non- Fermenting) chromatin remodeling complex including and ....
Cancer genomic studies have identified frequent alterations in components of the SWI/SNF (SWItch/Sucrose Non- Fermenting) chromatin remodeling complex including and . Importantly, clinical reports indicate that -mutant lung cancers respond poorly to immunotherapy and have dismal prognosis. However, the mechanistic basis of immunotherapy resistance is unknown. Here, we corroborated the clinical findings by using immune-humanized, syngeneic, and genetically engineered mouse models of lung cancer harboring deficiency. Specifically, we show that loss caused decreased response to anti-PD1 immunotherapy associated with significantly reduced infiltration of dendritic cells (DCs) and CD4+ T cells into the tumor microenvironment (TME). Mechanistically, we show that loss in tumor cells led to profound downregulation of and other components of the innate immune system as well as inflammatory cytokines that are required for efficient recruitment and activity of immune cells. We establish that this deregulation of gene expression is caused by cancer cell-intrinsic reprogramming of the enhancer landscape with marked loss of chromatin accessibility at enhancers of genes involved in innate immune response such as type I IFN and inflammatory cytokines. Interestingly, we observed that transcription factor NF-κB binding motif was highly enriched in enhancers that lose accessibility upon deficiency. Finally, we confirmed that SMARCA4 and NF-κB co-occupy the same genomic loci on enhancers associated with and indicating a functional interplay between SMARCA4 and NF-κB. Taken together, our findings provide the mechanistic basis for the poor response of -mutant tumors to anti-PD1 immunotherapy and establish a functional link between SMARCA4 and NF-κB on innate immune and inflammatory gene expression regulation.
PubMed: 38948751
DOI: 10.1101/2024.06.18.599431 -
The Journal of Innovations in Cardiac... Jun 2024Atrial fibrillation (AF) is a prevalent cardiac arrhythmia marked by irregular and frequent tachycardic rhythms in the atria, affecting 1%-2% of the general population.... (Review)
Review
Comparative Profiles of the WATCHMAN™ and Amplatzer™ Cardiac Plug/Amplatzer™ Amulet™ Devices for Left Atrial Appendage Closure in Non-valvular Atrial Fibrillation: A Comprehensive Systematic Review and Meta-analysis.
Atrial fibrillation (AF) is a prevalent cardiac arrhythmia marked by irregular and frequent tachycardic rhythms in the atria, affecting 1%-2% of the general population. The WATCHMAN™ device from Boston Scientific (Marlborough, MA, USA) and the Amplatzer™ Amulet™ device from Abbott (Chicago, IL, USA) are two devices used globally for left atrial appendage closure (LAAC) in non-valvular AF. A systematic search was conducted in PubMed, the Cochrane Library, and Elsevier's ScienceDirect literature databases to identify studies comparing the WATCHMAN™ procedure with Amulet™ device implantation for LAAC in patients with AF. The analyses were conducted using the random-effects model. A total of 20 studies were identified, with 18 falling into the category of observational studies and 2 being randomized controlled trials. A total of 6310 participants were included in this meta-analysis, with 3198 individuals (50.68%) assigned to the WATCHMAN™ procedure group and 3112 individuals (49.32%) allocated to the Amplatzer™ Cardiac Plug (ACP) group. The analysis revealed a higher risk of stroke associated with the WATCHMAN™ technique (relative risk [RR], 1.14), albeit without statistical significance. Conversely, the WATCHMAN™ approach led to a significantly lower risk of cardiac death (RR, 0.44; = .04). Notably, the risks of all-cause mortality (RR, 0.89; 95% confidence interval [CI], 0.73-1.08; = 0%; = .25) and major bleeding (RR, 0.93; 95% CI, 0.65-1.33; = 31%; = .70) were clinically reduced with the WATCHMAN™ procedure, although statistical significance was not achieved. Compared to Amulet™ device implantation, WATCHMAN™ device implantation decreased the risk of cardiac mortality, while the risks of stroke, systemic embolism, all-cause mortality, and major bleeding were not statistically significant.
PubMed: 38948665
DOI: 10.19102/icrm.2024.15061