Beta-adrenergic agonism protects mitochondrial metabolism in the pancreatectomised rat heart.

The diabetic heart is characterised by functional, morphological and metabolic alterations predisposing it to contractile failure. Chronic sympathetic activation is a feature of the pathogenesis of heart failure, however the type 1 diabetic heart shows desensitisation to ß-adrenergic stimulation. Here, we sought to understand the impact of repeated isoprenaline-mediated ß-stimulation upon cardiac mitochondrial respiratory capacity and substrate metabolism in the 90% pancreatectomy (Px) rat model of type 1 diabetes. We hypothesised these hearts would be relatively protected against the metabolic impact of stress-induced cardiomyopathy. We found that individually both Px and isoprenaline suppressed cardiac mitochondrial respiration, but that this was preserved in Px rats receiving isoprenaline. Px and isoprenaline had contrasting effects on cardiac substrate metabolism, with increased reliance upon cardiac fatty acid oxidation capacity and altered ketone metabolism in the hearts of Px rats, but enhanced capacity for glucose uptake and metabolism in isoprenaline-treated rats. Moreover, Px rats were protected against isoprenaline-induced mortality, whilst isoprenaline elevated cGMP and protected myocardial energetic status in Px rat hearts. Our work suggests that adrenergic stimulation may be protective in the type 1 diabetic heart, and underlines the importance of studying pathological features in combination when modeling complex disease in rodents.

National Vaccination Coverage Among Adolescents Aged 13-17 Years - National Immunization Survey-Teen, United States, 2023.

Based on safety and efficacy data, vaccinations are the best defense to protect persons and communities from serious vaccine-preventable diseases. The Advisory Committee on Immunization Practices recommends routine vaccination of adolescents aged 11-12 years with three vaccines including tetanus, diphtheria, and acellular pertussis vaccine; quadrivalent meningococcal conjugate vaccine; and human papillomavirus vaccine. CDC analyzed data from the 2023 National Immunization Survey-Teen for 16,658 adolescents aged 13-17 years (born during January 2005-December 2010) to assess vaccination coverage in 2023, recent trends in coverage by birth year, and trends in coverage by eligibility for the Vaccines for Children (VFC) program and birth year. In 2023, coverage with all routine vaccines recommended for adolescents was similar to coverage in 2022. Vaccination coverage among VFC-eligible adolescents was generally stable during the COVID-19 pandemic, except for a decrease in the percentage of VFC-eligible adolescents who were up to date with HPV vaccination by age 13 years among those born in 2010 compared with those born in 2007. Whereas coverage differences were found between VFC-eligible and non-VFC-eligible adolescents before the COVID-19 pandemic, coverage was similar among the most recent birth years in the survey. Providers should make strong recommendations for all routine vaccines and review adolescent vaccination records to verify if adolescents are up to date with all recommended vaccines.

Vital Signs: Trends and Disparities in Childhood Vaccination Coverage by Vaccines for Children Program Eligibility - National Immunization Survey-Child, United States, 2012-2022.

Introduction: The Vaccines for Children (VFC) program was established in 1994 to provide recommended vaccines at no cost to eligible children and help ensure that all U.S. children are protected from life-threatening vaccine-preventable diseases. Methods: CDC analyzed data from the 2012-2022 National Immunization Survey-Child (NIS-Child) to assess trends in vaccination coverage with ≥1 dose of measles, mumps, and rubella vaccine (MMR), 2-3 doses of rotavirus vaccine, and a combined 7-vaccine series, by VFC program eligibility status, and to examine differences in coverage among VFC-eligible children by sociodemographic characteristics. VFC eligibility was defined as meeting at least one of the following criteria: 1) American Indian or Alaska Native; 2) insured by Medicaid, Indian Health Service (IHS), or uninsured; or 3) ever received at least one vaccination at an IHS-operated center, Tribal health center, or urban Indian health care facility. Results: Overall, approximately 52.2% of U.S. children were VFC eligible. Among VFC-eligible children born during 2011-2020, coverage by age 24 months was stable for ≥1 MMR dose (88.0%-89.9%) and the combined 7-vaccine series (61.4%-65.3%). Rotavirus vaccination coverage by age 8 months was 64.8%-71.1%, increasing by an average of 0.7 percentage points annually. Among all children born in 2020, coverage was 3.8 (≥1 MMR dose), 11.5 (2-3 doses of rotavirus vaccine), and 13.8 (combined 7-vaccine series) percentage points lower among VFC-eligible than among non-VFC-eligible children. Conclusions and implications for public health practice: Although the VFC program has played a vital role in increasing and maintaining high levels of childhood vaccination coverage for 30 years, gaps remain. Enhanced efforts must ensure that parents and guardians of VFC-eligible children are aware of, have confidence in, and are able to obtain all recommended vaccines for their children.

Anatomical evaluation of the superficial parasternal intercostal plane block.

BACKGROUND AND OBJECTIVES: Few cadaveric studies have evaluated the dye spread with superficial parasternal intercostal plane (SPIP) blocks. In this study, we examined the dye spread of an ultrasound-guided SPIP block in a human cadaveric model with single and double injection techniques. METHODS: Seven single and four double ultrasound-guided SPIP blocks were performed in seven unembalmed human cadavers using an in-plane approach with the transducer oriented parasagitally 1 cm lateral to the sternum. For the single SPIP, 20 mL of 0.166% methylene blue was injected in the second or third intercostal space into the plane between the Pec major muscle and internal intercostal muscles. For the double SPIP, 10 mL of 0.166% methylene blue was injected in the SPIP at one intercostal space with an additional 10 mL injected in the SPIP two intercostal spaces caudally. The extent of dye spread was documented. RESULTS: For all SPIP injections, there was consistent mediolateral spread from the sternum to the mid-clavicular line, with many extending laterally to the anterior axillary line. There was craniocaudal spread to a median of 2 intercostal muscles with a single SPIP and 3 intercostal muscles with a double SPIP. There was a median spread to 1 intercostal nerve for the single SPIP and 1.5 intercostal nerves with the double SPIP. CONCLUSIONS: The SPIP block demonstrated limited spread in this cadaver study. A single injection of this block may be of limited value and multiple SPIP injections may be needed to have adequate spread for anterior thoracic procedures.

Fluorinated trehalose analogues for cell surface engineering and imaging of Mycobacterium tuberculosis.

The sensitive, rapid and accurate diagnosis of Mycobacterium tuberculosis (Mtb) infection is a central challenge in controlling the global tuberculosis (TB) pandemic. Yet the detection of mycobacteria is often made difficult by the low sensitivity of current diagnostic tools, with over 3.6 million TB cases missed each year. To overcome these limitations there is an urgent need for next-generation TB diagnostic technologies. Here we report the use of a discrete panel of native 19F-trehalose (F-Tre) analogues to label and directly visualise Mtb by exploiting the uptake of fluorine-modified trehalose analogues via the mycobacterial trehalose LpqY-SugABC ATP-binding cassette (ABC) importer. We discovered the extent of modified F-Tre uptake correlates with LpqY substrate recognition and characterisation of the interacting sites by saturation transfer difference NMR coupled with molecular dynamics provides a unique glimpse into the molecular basis of fluorine-modified trehalose import in Mtb. Lipid profiling demonstrated that F-Tre analogues modified at positions 2, 3 and 6 are incorporated into mycobacterial cell-surface trehalose-containing glycolipids. This rapid one-step labelling approach facilitates the direct visualisation of F-Tre-labelled Mtb by Focused Ion Beam (FIB) Secondary Ion Mass Spectrometry (SIMS), enabling detection of the Mtb pathogen. Collectively, our findings highlight that F-Tre analogues have potential as tools to probe and unravel Mtb biology and can be exploited to detect and image TB.

Demographic characteristics and clinical features of patients presenting with different forms of cutaneous leishmaniasis, in Lay Gayint, Northern Ethiopia.

Cutaneous leishmaniasis (CL) is a neglected tropical disease caused by Leishmania parasites, that can cause long-term chronic disabilities. The clinical presentation of CL varies in both type and severity. CL presents as three main clinical forms: localised lesions (localised cutaneous leishmaniasis, LCL); mucocutaneous leishmaniasis (MCL) that affects the mucosa of the nose or the mouth; or as disseminated not ulcerating nodules (diffuse cutaneous leishmaniasis, DCL). Here we recruited a cohort of CL patients in a newly established leishmaniasis treatment centre (LTC) in Lay Gayint, Northwest Ethiopia, and collected detailed demographic and clinical data. The results of our study show that more males than females present to the LTC to seek diagnosis and treatment. 70.2% of CL patients presented with LCL and 20.8% with MCL. A small number of patients presented with DCL, recidivans CL (a rare form of CL where new lesions appear on the edges of CL scars) or with a combination of different clinical presentations. The duration of illness varied from 1 month to 180 months. Over a third of CL patients had additional suspected CL cases in their household. Despite the majority of CL patients having heard about CL, only a minority knew about its transmission or that it could be treated. Most CL patients lived in areas where environmental factors known to be associated with the transmission of CL were present. This work highlights that CL is an important public health problem in Lay Gayint and emphasises the urgent need for more CL awareness campaigns, better health education and better disease management practices.

Mispacking of the F87 sidechain drives aggregation-promoting conformational fluctuations in the subunit interfaces of the transthyretin tetramer.

Aberrant formation and deposition of human transthyretin (TTR) aggregates causes transthyretin amyloidosis. To initialize aggregation, transthyretin tetramers must first dissociate into monomers that partially unfold to promote entry into the aggregation pathway. The native TTR tetramer (T) is stabilized by docking of the F87 sidechain into an interfacial cavity enclosed by several hydrophobic residues including A120. We have previously shown that an alternative tetramer (T*) with mispacked F87 sidechains is more prone to dissociation and aggregation than the native T state. However, the molecular basis for the reduced stability in T* remains unclear. Here we report characterization of the A120L mutant, where steric hindrance is introduced into the F87 binding site. The x-ray structure of A120L shows that the F87 sidechain is displaced from its docking site across the subunit interface. In A120S, a naturally occurring pathogenic mutant that is less aggregation-prone than A120L, the F87 sidechain is correctly docked, as in the native TTR tetramer. Nevertheless, 19F-NMR aggregation assays show an elevated population of a monomeric aggregation intermediate in A120S relative to a control containing the native A120, due to accelerated tetramer dissociation and slowed monomer tetramerization. The mispacking of the F87 sidechain is associated with enhanced exchange dynamics for interfacial residues. At 298 K, the T* populations of various naturally occurring mutants fall between 4% and 7% (ΔG ~ 1.5-1.9 kcal/mol), consistent with the free energy change expected for undocking and solvent exposure of one of the four F87 sidechains in the tetramer (ΔG ~ 1.6 kcal/mol). Our data provide a molecular-level picture of the likely universal F87 sidechain mispacking in tetrameric TTR that promotes interfacial conformational dynamics and increases aggregation propensity.

Effect of Delayed Parathyroidectomy on Risk of Future Cardiovascular and Nephrolithiasis Interventions in Adults with Primary Hyperparathyroidism [Original Study].

OBJECTIVE: To determine whether the timing of parathyroid surgery impacts the risk of renal stone retreatment and cardiovascular interventions. SUMMARY BACKGROUND DATA: Long-term, untreated primary hyperparathyroidism is associated with significant morbidity including nephrolithiasis and cardiovascular disease. METHODS: We conducted a Population-based Cohort study of New York and California state-wide data from 2000-2020. Adult patients who underwent renal stone treatment and subsequently diagnosed with primary hyperparathyroidism (pHPT) and underwent parathyroidectomy (PTX) were included. Patients were excluded if PTX was prior to index stone procedure, they underwent second stone treatment within 6 months, with stage V CKD, with secondary or tertiary hyperparathyroidism, with prior kidney transplant or hemodialysis, or with prior cancer diagnosis. Rate of renal stone retreatment and cardiovascular interventions after PTX in pHPT patients with nephrolithiasis who underwent parathyroid surgery at ≤ 2 years and >2 years after index stone procedure was measured. RESULTS: We identified 2,093 patients who underwent first-time stone treatment and subsequent PTX. The median time to PTX was 560 days (IQR 187-1477) and follow-up was 7.4 years (IQR 4.5-13.1). Delaying PTX for more than 2 years increased the risk of renal stone retreatment by 59% (HR 1.59; P<0.001), increased the risk of experiencing coronary disease or associated interventions by 118% (HR=2.18; P=0.01), and increased the risk of experiencing an overall cardiovascular event by 52% (HR 1.52; P<0.01). CONCLUSIONS AND RELEVANCE: In symptomatic pHPT, delaying PTX significantly increases the risk of requiring future stone retreatment and cardiac/vascular surgical interventions. This highlights the importance of early surgical referral and multidisciplinary approaches to optimize outcomes and resource utilization in pHPT.

Validation of a Low-Cost Manometer to Assess of Tongue, Lip, Cheek, and Respiratory Strength: A Laboratory-Based Study.

OBJECTIVE(S): The objective of this study was to characterize the level of agreement between three manometers: (1) Iowa Oral Performance Instrument (IOPI)-the reference standard for tongue, lip, and cheek strength assessments; (2) MicroRPM Respiratory Pressure Meter (MicroRPM)-the reference standard for respiratory strength assessments; and (3) Digital Pressure Manometer (DPM)-an alternative, low-cost pressure testing manometer. METHODS: Manual pressures were simultaneously applied to the IOPI and DPM, and to the MicroRPM and DPM, within a controlled laboratory setting. Agreement in pressure readings were analyzed using descriptive statistics, Lin's concordance correlation, and Bland-Altman Plots. Agreement was interpreted as "poor" if ρc < 0.90, "moderate" if ρc = 0.90 - < 0.95, "substantial" if ρc = 0.95 - < 0.99, and "excellent" if ρc ≥ 0.99. RESULTS: Differences in pressure readings between the DPM and clinical reference standards were consistently present yet highly predictable. There was a median absolute difference of 2.0-3.9 kPa between the IOPI and DPM, and 4.5-9.8 cm H2O between the MicroRPM and DPM. Lin's concordance revealed "substantial" agreement between the IOPI and DPM (ρc = 0.98) and the MicroRPM and DPM (ρc = 0.99). CONCLUSION: The DPM revealed higher pressure readings when compared to the IOPI and MicroRPM. However, differences in pressure readings were relatively small, highly predictable, and yielded substantial overall agreement. These findings suggest the DPM may be a valid, lower-cost alternative for objective assessments of tongue, lip, cheek, and respiratory muscle strength. Future research should expand on the present findings in clinical patient populations. LEVEL OF EVIDENCE: NA Laryngoscope, 2024.

Cooperative genomic lesions in HRAS-mutant cancers predict resistance to farnesyltransferase inhibitors.

In the clinical development of farnesyltransferase inhibitors (FTIs) for HRAS-mutant tumors, responses varied by cancer type. Co-occurring mutations may affect responses. We aimed to uncover cooperative genetic events specific to HRAS-mutant tumors and to study their effect on sensitivity to FTIs. Using targeted sequencing data from the MSK-IMPACT and Dana-Farber Cancer Institute Genomic Evidence Neoplasia Information Exchange databases, we identified comutations that were observed predominantly in HRAS-mutant versus KRAS-mutant or NRAS-mutant cancers. HRAS-mutant cancers had a higher frequency of coaltered mutations (48.8%) in the MAPK, PI3K, or RTK pathway genes, compared with KRAS-mutant (41.4%) and NRAS-mutant (38.4%) cancers (p < 0.05). Class 3 BRAF, NF1, PTEN, and PIK3CA mutations were more prevalent in HRAS-mutant lineages. To study the effects of comutations on sensitivity to FTIs, HrasG13R was transfected into "RASless" (Kraslox/lox/Hras-/-/Nras-/-/RERTert/ert) mouse embryonic fibroblasts (MEFs), which sensitized nontransfected MEFs to tipifarnib. Comutation in the form of Pten or Nf1 deletion and Pik3caH1047R transduction led to resistance to tipifarnib in HrasG13R-transfected MEFs in the presence or absence of KrasWT, whereas BrafG466E transduction led to resistance to tipifarnib only in the presence of KrasWT. Combined treatment with tipifarnib and MEK inhibition sensitized cells to tipifarnib in all settings, including in MEFs with PI3K pathway comutations. HRAS-mutant tumors demonstrate lineage-dependent MAPK or PI3K pathway alterations, which confer resistance to tipifarnib. The combined use of FTIs and MEK inhibition is a promising strategy for HRAS-mutant tumors.

"Fast but not so furious": A condensed step-up dosing schedule of teclistamab for relapsed/refractory multiple myeloma.

Teclistamab is a B-cell maturation antigen (BCMA)-directed bispecific T-cell engager approved for relapsed-refractory multiple myeloma (RRMM). Cytokine release syndrome (CRS) and Immune effector cell-associated neurotoxicity syndrome (ICANS) are well-documented treatment -related adverse events of teclistamab. The prescribing information recommends step-up dosing on days 1, 4, and 7 with 48-72 h of inpatient observation after each dose to monitor for CRS. This leads to a more than weeklong hospital stay, adding to the cost of therapy, resource utilization, and patient inconvenience. Here, we present a single center retrospective analysis addressing the safety and utility of a condensed step-up dosing schedule for teclistamab. All patients who were treated with teclistamab from November 2022 to August 2023 at the Medical University of South Carolina were included in the analysis. Patients received subcutaneous (SC) teclistamab with step-up doses (0.06 and 0.3 mg/kg) separated by either 2 or 3 (48-72 h) before the administration of the first full (1.5 mg/kg) dose (days 1, 3, and 5 'condensed' schedule or days 1, 4, and 7 'standard' schedule, respectively). All patients were hospitalized for the two step-up doses and first full dose of teclistamab and received pre-medications prior to each dose. Patients could be discharged after a minimum of 24 h following the full dose, if they did not have any CRS or ICANS. Relevant data regarding incidence, severity, and onset of CRS was collected. Statistical analysis was completed to assess the probability of fever with the first full dose of teclistamab based on incidence of fever with previous doses. A total of 25 patients were included in the analysis. Twenty-eight percent (7/25) of patients underwent the standard step up while the remaining 72% (18/25) underwent a condensed step up of teclistamab. More than half (53%, 13/25) of the patients experienced CRS during step up dosing. Grades 1 and 2 CRS occurred in 48% (12/25) and 4% (1/25) patients, respectively. Of the 13 patients that experienced CRS, 30% (4/13) fevered with the first dose, 84% (11/13) fevered with the second dose, and one patient developed fever after the third dose. The negative predictive value of being 'fever free' after doses 1 and 2 and remaining 'fever free' throughout hospitalization was 0.92. The median length of hospital stay among the 1, 3, and 5 step up group was 6 days (6-25) and 70% (14/20) of patients were discharged from the hospital within 7 days of treatment initiation. This report demonstrates the utility of a condensed step-up schedule for teclistamab initiation. The schedule was found to be safe and reduced hospital length of stay. These results should prompt consideration of shorter hospital stays for patients who do not experience CRS and raise the possibility of outpatient administration with close observation.

Voluntary co-contraction of ankle muscles alters motor unit discharge characteristics and reduces estimates of persistent inward currents.

Motoneuronal persistent inward currents (PICs) are facilitated by neuromodulatory inputs but are highly sensitive to local inhibitory circuits. Estimates of PICs are reduced by group Ia reciprocal inhibition, and increased with the diffuse actions of neuromodulators released during remote muscle contraction. However, it remains unknown how motoneurons function in the presence of simultaneous excitatory and inhibitory commands. To probe this topic, we investigated motor unit discharge patterns and estimated PICs during voluntary co-contraction of ankle muscles, which simultaneously demands the contraction of agonist-antagonist pairs. Twenty participants performed triangular ramps of both co-contraction (simultaneous dorsiflexion and plantar flexion) and isometric dorsiflexion to a peak of 30% of their maximum muscle activity from a maximal voluntary contraction. Motor unit spike trains were decomposed from high-density surface EMG activity recorded from tibialis anterior using blind source separation algorithms. Voluntary co-contraction altered motor unit discharge rate characteristics. Discharge rate at recruitment and peak discharge rate were modestly reduced (∼6% change; P < 0.001; d = 0.22) and increased (∼2% change; P = 0.001, d = -0.19), respectively, in the entire dataset but no changes were observed when motor units were tracked across conditions. The largest effects during co-contraction were that estimates of PICs (ΔF) were reduced by ∼20% (4.47 vs. 5.57 pulses per second during isometric dorsiflexion; P < 0.001, d = 0.641). These findings suggest that, during voluntary co-contraction, the inhibitory input from the antagonist muscle overcomes the additional excitatory and neuromodulatory drive that may occur due to the co-contraction of the antagonist muscle, which constrains PIC behaviour. KEY POINTS: Voluntary co-contraction is a unique motor behaviour that concurrently provides excitatory and inhibitory synaptic input to motoneurons. Co-contraction of agonist-antagonist pairs alters agonist motor unit discharge characteristics, consistent with reductions in persistent inward current magnitude.

Does attachment in adolescence predict neural responses to handholding in adulthood? A functional magnetic resonance imaging study.

Objective: Early life experiences, including attachment-related experiences, inform internal working models that guide adult relationship behaviors. Few studies have examined the association between adolescent attachment and adult relationship behavior on a neural level. The current study examined attachment in adolescence and its associations with neural correlates of relationship behaviors in adulthood. Method: 85 participants completed the Adult Attachment Interview (AAI) at age 14. Ten years later, at age 24, participants underwent functional brain image when participants were under the threat of electric shock alone, holding the hand of a stranger, or their partner. Results: We found that adolescents who were securely attached at age 14 showed increased activation in regions commonly associated with cognitive, affective, and reward processing when they held the hand of their partner and stranger compared to being alone. Adolescents with higher preoccupied attachment scores showed decreased activation in similar regions only during the stranger handholding condition compared to being alone. Conclusions: These findings suggest that adolescent attachment predicts adult social relationship behaviors on a neural level, in regions largely consistent with previous literature. Broadly, this study has implications for understanding long-term links between attachment and adult relationship behaviors and has potential for informing intervention.

A multiplexed high throughput screening assay using flow cytometry identifies glycolytic molecular probes in bloodstream form Trypanosoma brucei.

Kinetoplastid organisms, including Trypanosoma brucei, are a significant health burden in many tropical and semitropical countries. Much of their metabolism is poorly understood. To better study kinetoplastid metabolism, chemical probes that inhibit kinetoplastid enzymes are needed. To discover chemical probes, we have developed a high-throughput flow cytometry screening assay that simultaneously measures multiple glycolysis-relevant metabolites in live T. brucei bloodstream form parasites. We transfected parasites with biosensors that measure glucose, ATP, or glycosomal pH. The glucose and ATP sensors were FRET biosensors, while the pH sensor was a GFP-based biosensor. The pH sensor exhibited a different fluorescent profile from the FRET sensors, allowing us to simultaneously measure pH and either glucose or ATP. Cell viability was measured in tandem with the biosensors using thiazole red. We pooled sensor cell lines, loaded them onto plates containing a compound library, and then analyzed them by flow cytometry. The library was analyzed twice, once with the pooled pH and glucose sensor cell lines and once with the pH and ATP sensor cell lines. Multiplexing sensors provided some internal validation of active compounds and gave potential clues for each compound's target(s). We demonstrated this using the glycolytic inhibitor 2-deoxyglucose and the alternative oxidase inhibitor salicylhydroxamic acid. Individual biosensor-based assays exhibited a Z'-factor value acceptable for high-throughput screening, including when multiplexed. We tested assay performance in a pilot screen of 14,976 compounds from the Life Chemicals Compound Library. We obtained hit rates from 0.2 to 0.4% depending on the biosensor, with many compounds impacting multiple sensors. We rescreened 44 hits, and 28 (64%) showed repeatable activity for one or more sensors. One compound exhibited EC50 values in the low micromolar range against two sensors. We expect this method will enable the discovery of glycolytic chemical probes to improve metabolic studies in kinetoplastid parasites.

Astrocyte Gi-GPCR signaling corrects compulsive-like grooming and anxiety-related behaviors in Sapap3 knockout mice.

Astrocytes are morphologically complex cells that serve essential roles. They are widely implicated in central nervous system (CNS) disorders, with changes in astrocyte morphology and gene expression accompanying disease. In the Sapap3 knockout (KO) mouse model of compulsive and anxiety-related behaviors related to obsessive-compulsive disorder (OCD), striatal astrocytes display reduced morphology and altered actin cytoskeleton and Gi-G-protein-coupled receptor (Gi-GPCR) signaling proteins. Here, we show that normalizing striatal astrocyte morphology, actin cytoskeleton, and essential homeostatic support functions by targeting the astrocyte Gi-GPCR pathway using chemogenetics corrected phenotypes in Sapap3 KO mice, including anxiety-related and compulsive behaviors. Our data portend an astrocytic pharmacological strategy for rescuing phenotypes in brain disorders that include compromised astrocyte morphology and tissue support.

Effects of Nesting Material and Housing Parameters on Feed Wastage Behavior in Female Swiss Webster Mice.

Feed wastage in laboratory mice, also known as chewing or grinding behavior, is problematic for program management and animal welfare. The destruction of pelleted feed without consumption produces a powder accumulation on the cage floor called orts. Ort accumulation disrupts the cage microenvironment and can clog Lixits resulting in flooding. Moreover, added labor adds cost, and cage disruption increases animal stress. Published studies examining the behavior and ways to mitigate it have had inconsistent results, and the cause or causes have not yet been fully identified. The purpose of this study was to identify methods to reduce the development of chewing behavior in laboratory mice. Female Swiss Webster (Tac:SW) mice (n = 144) were randomly assigned to one of 8 groups (12 cages per group) with 2 housing densities (single and pair) and 4 nesting material paradigms. Mice were housed on clean bedding for 8 wk and then soiled bedding for the next 8 wk. Chewing behavior was evaluated by feed weight, cage weight, and feed scores. The addition of a Diamond Twist significantly increased ort production, while nest transfer decreased it but not significantly. Pair housing increased overall orts but not when adjusted for animal number. These results identified potential contributing factors to chewing behavior. However, further research is needed to elucidate the exact causes and solutions.

First Dorsal Compartment Release During Volar Approach for Distal Radius Fracture Fixation Reduces Symptoms in Patients With Pre-Existing De Quervain Disease.

Purpose: Release of the first dorsal compartment is a described technique during volar approach for distal radius fracture fixation. Our objective was to determine whether release of the first dorsal compartment during volar approach for distal radius fracture fixation impacted corresponding symptoms in pre-existing de Quervain disease. Methods: A prospective, randomized cohort study was performed with patients grouped for release (release group) or no release (control group) of the first dorsal compartment during volar approach for distal radius fracture fixation. Inclusion required a confirmed diagnosis of de Quervain disease within the 12 months preceding a distal radius fracture. Results: Patients in the release group were significantly less symptomatic than those in the control group at 3 and 6 months after surgery. Lateral pinch strength in the release group was significantly greater than that in the control group at 3 and 6 months after surgery. Conclusions: The current results demonstrated a significantly greater reduction in de Quervain disease symptoms in the release group compared with the no release group during the short-term follow-up. This indicates that routine first dorsal compartment release during distal radius fracture fixation may expedite symptom relief in patients with de Quervain disease. Type of study/level of evidence: Therapeutic I.

Secretome analysis of oligodendrocytes and precursors reveals their roles as contributors to the extracellular matrix and potential regulators of inflammation.

Oligodendrocytes form myelin that ensheaths axons and accelerates the speed of action potential propagation. Oligodendrocyte progenitor cells (OPCs) proliferate and replenish oligodendrocytes. While the myelin-forming role of oligodendrocytes and OPCs is well-established, potential additional roles of these cells are yet to be fully explored. Here, we analyzed the secreted proteome of oligodendrocytes and OPCs in vitro to determine whether these cell types are major sources of secreted proteins in the central nervous system (CNS). Interestingly, we found that both oligodendrocytes and OPCs secret various extracellular matrix proteins. Considering the critical role of neuroinflammation in neurological disorders, we evaluated the responses and potential contributions of oligodendrocytes and OPCs to this process. By characterizing the secreted proteomes of these cells after pro-inflammatory cytokine treatment, we discovered the secretion of immunoregulators such as C2 and B2m. This finding sheds new light on the hitherto underappreciated role of oligodendrocytes and OPCs in actively modulating neuroinflammation. Our study provides a comprehensive and unbiased proteomic dataset of proteins secreted by oligodendrocyte and OPC under both physiological and inflammatory conditions. It revealed the potential of these cells to secrete matrix and signaling molecules, highlighting their multifaceted function beyond their conventional myelin-forming roles.

Mechanism-guided engineering of a minimal biological particle for genome editing.

The widespread application of genome editing to treat or even cure disease requires the delivery of genome editors into the nucleus of target cells. Enveloped Delivery Vehicles (EDVs) are engineered virally-derived particles capable of packaging and delivering CRISPR-Cas9 ribonucleoproteins (RNPs). However, the presence of lentiviral genome encapsulation and replication components in EDVs has obscured the underlying delivery mechanism and precluded particle optimization. Here we show that Cas9 RNP nuclear delivery is independent of the native lentiviral capsid structure. Instead, EDV-mediated genome editing activity corresponds directly to the number of nuclear localization sequences on the Cas9 enzyme. EDV structural analysis using cryo-electron tomography and small molecule inhibitors guided the removal of ~80% of viral residues, creating a minimal EDV (miniEDV) that retains full RNP delivery capability. MiniEDVs are 25% smaller yet package equivalent amounts of Cas9 RNPs relative to the original EDVs, and demonstrated increased editing in cell lines and therapeutically-relevant primary human T cells. These results show that virally-derived particles can be streamlined to create efficacious genome editing delivery vehicles that could simplify production and manufacturing.