Polyethylene glycol has immunoprotective effects on sciatic allografts, but behavioral recovery and graft tolerance require neurorrhaphy and axonal fusion.

JOURNAL/nrgr/04.03/01300535-202504000-00033/figure1/v/2024-07-06T104127Z/r/image-tiff Behavioral recovery using (viable) peripheral nerve allografts to repair ablation-type (segmental-loss) peripheral nerve injuries is delayed or poor due to slow and inaccurate axonal regeneration. Furthermore, such peripheral nerve allografts undergo immunological rejection by the host immune system. In contrast, peripheral nerve injuries repaired by polyethylene glycol fusion of peripheral nerve allografts exhibit excellent behavioral recovery within weeks, reduced immune responses, and many axons do not undergo Wallerian degeneration. The relative contribution of neurorrhaphy and polyethylene glycol-fusion of axons versus the effects of polyethylene glycol per se was unknown prior to this study. We hypothesized that polyethylene glycol might have some immune-protective effects, but polyethylene glycol-fusion was necessary to prevent Wallerian degeneration and functional/behavioral recovery. We examined how polyethylene glycol solutions per se affect functional and behavioral recovery and peripheral nerve allograft morphological and immunological responses in the absence of polyethylene glycol-induced axonal fusion. Ablation-type sciatic nerve injuries in outbred Sprague-Dawley rats were repaired according to a modified protocol using the same solutions as polyethylene glycol-fused peripheral nerve allografts, but peripheral nerve allografts were loose-sutured (loose-sutured polyethylene glycol) with an intentional gap of 1-2 mm to prevent fusion by polyethylene glycol of peripheral nerve allograft axons with host axons. Similar to negative control peripheral nerve allografts not treated by polyethylene glycol and in contrast to polyethylene glycol-fused peripheral nerve allografts, animals with loose-sutured polyethylene glycol peripheral nerve allografts exhibited Wallerian degeneration for all axons and myelin degeneration by 7 days postoperatively and did not recover sciatic-mediated behavioral functions by 42 days postoperatively. Other morphological signs of rejection, such as collapsed Schwann cell basal lamina tubes, were absent in polyethylene glycol-fused peripheral nerve allografts but commonly observed in negative control and loose-sutured polyethylene glycol peripheral nerve allografts at 21 days postoperatively. Loose-sutured polyethylene glycol peripheral nerve allografts had more pro-inflammatory and less anti-inflammatory macrophages than negative control peripheral nerve allografts. While T cell counts were similarly high in loose-sutured-polyethylene glycol and negative control peripheral nerve allografts, loose-sutured polyethylene glycol peripheral nerve allografts expressed some cytokines/chemokines important for T cell activation at much lower levels at 14 days postoperatively. MHCI expression was elevated in loose-sutured polyethylene glycol peripheral nerve allografts, but MHCII expression was modestly lower compared to negative control at 21 days postoperatively. We conclude that, while polyethylene glycol per se reduces some immune responses of peripheral nerve allografts, successful polyethylene glycol-fusion repair of some axons is necessary to prevent Wallerian degeneration of those axons and immune rejection of peripheral nerve allografts, and produce recovery of sensory/motor functions and voluntary behaviors. Translation of polyethylene glycol-fusion technologies would produce a paradigm shift from the current clinical practice of waiting days to months to repair ablation peripheral nerve injuries.

Muscle-to-Bone Ratio in NCAA Division I Collegiate Football Players by Position.

ABSTRACT: Dengel, DR, Studee, HR, Juckett, WT, Bosch, TA, Carbuhn, AF, Stanforth, PR, and Evanoff, NG. Muscle-to-bone ratio in NCAA division I collegiate football players by position. J Strength Cond Res XX(X): 000-000, 2024-The purpose of this study was to compare the muscle-to-bone ratio (MBR) in National Collegiate Athletic Association Division I football players (collegiate football players [CFP]) to healthy, age-matched controls. In addition, we examined MBR in CFP by position. A total of 553 CFP and 261 controls had their total and regional lean mass (LM), fat mass (FM), and bone mineral content (BMC) determined by dual x-ray absorptiometry (DXA). College football players were categorized by positions defined as offensive linemen (OL), defensive linemen (DL), tight end, linebacker (LB), running back (RB), punter or kicker, quarterback (QB), defensive back (DB), and wide receiver (WR). There were significant differences between CFP and controls for total LM (80.1 ± 10.0 vs. 56.9 ± 7.8 kg), FM (22.2 ± 12.5 vs. 15.2 ± 7.1 kg), and BMC (4.3 ± 0.5 vs. 3.1 ± 0.5 kg). Although there were significant differences in body composition between CFP and controls, there was no significant differences in total MBR between CFP and controls (18.6 ± 1.4 vs. 18.8 ± 1.7). Regionally, CFP had significantly lower trunk MBR than controls (26.7 ± 2.7 vs. 28.7 ± 4.2), but no difference was seen in leg or arm MBR. Positional differences in CFP were noted as total MBR being significantly higher in DL (19.0 ± 1.4) than in DB (18.1 ± 1.3), WR (18.1 ± 1.3), and LB (18.2 ± 1.3). OL had a significantly higher total MBR (19.2 ± 1.3) than DB (18.1 ± 1.3), LB (18.2 ± 1.3), QB (18.1 ± 1.0), and WR (18.1 ± 1.3). In addition, RB had significantly higher total MBR (18.8 ± 1.3) than DB (18.1 ± 1.3) and WR (18.1 ± 1.3). This study may provide athletes and training staff with normative values when evaluating total and regional MBR with DXA.

PCCA variant rs16957301 is a novel AKI risk genotype-specific for patients who receive ICI treatment: Real-world evidence from All of Us cohort.

Background: Immune checkpoint inhibitors (ICIs) enhance the immune system's ability to target and destroy cancer cells by blocking inhibitory pathways. Despite their efficacy, these treatments can trigger immune-related adverse events (irAEs), such as acute kidney injury (ICI-AKI), complicating patient management. The genetic predispositions to ICI-AKI are not well understood, necessitating comprehensive genomic studies to identify risk factors and improve therapeutic strategies. Objective: To identify genetic predispositions for ICI-AKI using large-scale real-world data. Methods: A systematic literature search led to 14 candidate variants related to irAEs. We performed a candidate variant association study with these 14 variants using the All of Us cohort (AoU, v7, cutoff date: 7/1/2022). A cohort for cancer patients receiving ICI and a general cohort were established to evaluate ICI-AKI risk. Logistic regression, adjusted for sex, was used to evaluate the impact of each candidate genotype, separately for self-reported and ancestry-estimated race. Kaplan-Meier survival analysis assessed the genetic effects on AKI-free survival. Results: The ICI cohort (n=414) showed a one-year AKI incidence rate of 23.2%, significantly higher than the general cohort (6.5%, n=213,282). The rs16957301 variant (chr13:100324308, T>C) in the PCCA gene was a significant risk genotype for ICI-AKI among self-reported Caucasians (Beta=0.93, Bonferroni-corrected P-value=0.047) and ancestry estimated Caucasians (Beta = 0.94, Bonferroni-corrected P-value=0.044). Self-reported Caucasians with the rs16957301 risk genotypes (TC/CC) developed AKI significantly earlier (3.6 months) compared to the reference genotype (TT, 7.0 months, log-rank P=0.04). Consistent results were found in ancestry-estimated Caucasians. This variant did not present significant AKI risks in the general cohort (Beta: -0.008-0.035, FDR: 0.75-0.99). Conclusion: Real-world evidence from the All of Us cohort suggests that, in Caucasians, PCCA variant rs16957301 is a novel AKI risk genotype specific to ICI treatment. Additional studies are warranted to validate rs16957301 as risk marker for AKI in Caucasian patients treated with ICIs and to assess its risk in other ancestral populations.

Predicting Clinical Improvement in Early Psychosis Using Circuit-Based Resting-State Functional Magnetic Resonance Imaging.

BACKGROUND AND HYPOTHESIS: Identifying biomarkers that predict treatment response in early psychosis (EP) is a priority for psychiatry research. Previous work suggests that resting-state connectivity biomarkers may have promise as predictive measures, although prior results vary considerably in direction and magnitude. Here, we evaluated the relationship between intrinsic functional connectivity of the attention, default mode, and salience resting-state networks and 12-month clinical improvement in EP. STUDY DESIGN: Fifty-eight individuals with EP (less than 2 years from illness onset, 35 males, average age 20 years) had baseline and follow-up clinical data and were included in the final sample. Of these, 30 EPs showed greater than 20% improvement in Brief Psychiatric Rating Scale (BPRS) total score at follow-up and were classified as "Improvers." STUDY RESULTS: The overall logistic regression predicting Improver status was significant (χ2 = 23.66, Nagelkerke's R2 = 0.45, P < .001, with 85% concordance). Significant individual predictors of Improver status included higher default mode within-network connectivity, higher attention-default mode between-network connectivity, and higher attention-salience between-network connectivity. Including baseline BPRS as a predictor increased model significance and concordance to 92%, and the model was not significantly influenced by the dose of antipsychotic medication (chlorpromazine equivalents). Linear regression models predicting percent change in BPRS were also significant. CONCLUSIONS: Overall, these results suggest that resting-state functional magnetic resonance imaging connectivity may serve as a useful biomarker of clinical outcomes in recent-onset psychosis.

Physiological carry-over effects of variable precipitation are mediated by reproductive status in a long-lived ungulate.

In the age of global climate change, extreme climatic events are expected to increase in frequency and severity. Animals will be forced to cope with these novel stressors in their environment. Glucocorticoids (i.e. 'stress' hormones) facilitate an animal's ability to cope with their environment. To date, most studies involving glucocorticoids focus on the immediate physiological effects of an environmental stressor on an individual, few studies have investigated the long-term physiological impacts of such stressors. Here, we tested the hypothesis that previous exposure to an environmental stressor will impart lasting consequences to an individual's glucocorticoid levels. In semi-arid environments, variable rainfall drives forage availability for herbivores. Reduced seasonal precipitation can present an extreme environmental stressor potentially imparting long-term impacts on an individual's glucocorticoid levels. We examined the effects of rainfall and environmental characteristics (i.e. soil and vegetation attributes) during fawn-rearing (i.e. summer) on subsequent glucocorticoid levels of female white-tailed deer (Odocoileus virginianus) in autumn. We captured 124 adult (≥2.5-year-old) female deer via aerial net-gunning during autumn of 2015, 2016 and 2021 across four populations spanning a gradient of environmental characteristics and rainfall in the semi-arid environment of South Texas, USA. We found for every 1 cm decrease in summer rainfall, faecal glucocorticoid levels in autumn increased 6.9%, but only in lactating females. Glucocorticoid levels in non-lactating, female deer were relatively insensitive to environmental conditions. Our study demonstrates the long-lasting effects of environmental stressors on an individual's glucocorticoid levels. A better understanding of the long-term effects stressors impart on an individual's glucocorticoid levels will help to evaluate the totality of the cost of a stressor to an individual's welfare and predict the consequences of future climate scenarios.

State of South Dakota's Child: 2023.

In 2022, there was a decrease in births in the state with 111 fewer resident newborns than in the previous year. This represented a decrease of 1% of its white and 3.5% of its AIBO (American Indian, Black and Other) births. The 2022 birth rate per 1,000 population for the state (12.3) is higher than observed nationally (10.9) but matches its 2020 rate that was an historic low. Approximately 22% of all births in 2022 were AIBO and this percent of the state's entire birth cohort has decreased in the past several years. The American Indian contribution to the AIBO cohort has also decreased as its racial diversity has increased. The percent of births that are low birth weight has consistently been lower in South Dakota than nationally. An increase of 16 infant deaths in 2022 from 2021 and the decreased number of births led to an increase in the infant mortality rate (IMR = deaths in first year of life per 1,000 live births) from 6.3 to 7.8, but this 2022 IMR is not statistically significantly higher than its previous five-year mean. Further, the 2022 increase in the IMR was almost entirely among white infants with the post neonatal mortality rate (PNMR = deaths between 28 and 365 days of life) decreasing between these two years for AIBO infants. Nonetheless, the state's five year mean rates of death (2018-2022) are significantly higher for the AIBO than white infants for the neonatal (0-27 days) and post neonatal periods of the first year of life. Recently, however, the ratio of AIBO to white post neonatal mortality rate (PNMR) has decreased, but increased for the neonatal mortality rate (NMR). Infants in South Dakota are significantly more likely between 2018 and 2022 to die of congenital anomalies, sudden unexpected infant death (SUID), and accidents/homicides than in the United States in 2021. SUID remains the leading cause of post neonatal death and its risk may be decreased when babies are placed to sleep supine and alone in environments that are devoid of soft hazards.

Modular Assembly of Metamaterials Using Light Gradients.

This is a report on a pilot study that tests the feasibility of assembling photonic metamaterials (PMs) using light gradient forces. Following a strategy that works like modular construction, light gradient forces, produced by a tightly focused, 1D standing wave optical trap, time-multiplexed across a 2D lattice are used to assemble voxels consisting of prefabricated, monodispersed nanoparticles (NPs) with radii ranging from 30 to 500 nm into 3D structures on a hydrogel scaffold. Hundreds of NPs can be manipulated concurrently into a complex heterogeneous voxel this way, and then the process can be repeated by stitching together voxels to form a metamaterial of any size, shape, and constituency although imperfectly. Imperfections introduce random phase shifts and amplitude variations that can have an adverse effect on the band structure. Regardless, PMs are created this way using two different dielectric NPs, polystyrene and rutile, and then the near-infrared performance for each is analyzed with angle-, wavelength-, and polarization-dependent reflection spectroscopy. The cross-polarized spectra show evidence of a resonance peak. Interestingly, whereas the line shape from the polystyrene array is symmetric, the rutile array is not, which may be indicative of Fano resonance. So, even with the structural defects, reflection spectroscopy reveals a resonance.

Genome-scale exon perturbation screens uncover exons critical for cell fitness.

CRISPR-Cas technology has transformed functional genomics, yet understanding of how individual exons differentially shape cellular phenotypes remains limited. Here, we optimized and conducted massively parallel exon deletion and splice-site mutation screens in human cell lines to identify exons that regulate cellular fitness. Fitness-promoting exons are prevalent in essential and highly expressed genes and commonly overlap with protein domains and interaction interfaces. Conversely, fitness-suppressing exons are enriched in nonessential genes, exhibiting lower inclusion levels, and overlap with intrinsically disordered regions and disease-associated mutations. In-depth mechanistic investigation of the screen-hit TAF5 alternative exon-8 revealed that its inclusion is required for assembly of the TFIID general transcription initiation complex, thereby regulating global gene expression output. Collectively, our orthogonal exon perturbation screens established a comprehensive repository of phenotypically important exons and uncovered regulatory mechanisms governing cellular fitness and gene expression.

Sialic Acid Receptor Specificity in Mammary Gland of Dairy Cattle Infected with Highly Pathogenic Avian Influenza A(H5N1) Virus.

In March 2024, the US Department of Agriculture's Animal and Plant Health Inspection Service reported detection of highly pathogenic avian influenza (HPAI) A(H5N1) virus in dairy cattle in the United States for the first time. One factor that determines susceptibility to HPAI H5N1 infection is the presence of specific virus receptors on host cells; however, little is known about the distribution of the sialic acid (SA) receptors in dairy cattle, particularly in mammary glands. We compared the distribution of SA receptors in the respiratory tract and mammary gland of dairy cattle naturally infected with HPAI H5N1. The respiratory and mammary glands of HPAI H5N1-infected dairy cattle are rich in SA, particularly avian influenza virus-specific SA α2,3-gal. Mammary gland tissues co-stained with sialic acids and influenza A virus nucleoprotein showed predominant co-localization with the virus and SA α2,3-gal. HPAI H5N1 exhibited epitheliotropism within the mammary gland, and we observed rare immunolabeling within macrophages.

What is the role of plastic surgery for incisional closures in pediatric spine surgery? Results from a pediatric spine study group survey.

Current best practice guidelines recommend a plastics-style multilayer wound closure for high-risk pediatric spine surgery. However, plastic surgery closure of spinal incisions remains controversial. This study investigates surgeon perceptions and practice patterns regarding plastic surgery multilayered closure (PMC) in pediatric spine surgery. All surgeons in an international pediatric spine study group received a 30-question survey assessing incisional closure practices, frequency of plastic surgery collaboration, and drain management. Relationship to practice size, setting, geographic region, and individual diagnoses were analyzed. 87/178 (49%) surgeons responded from 79% of participating sites. Plastics utilization rates differed by diagnosis: neuromuscular scoliosis 16.9%, early onset scoliosis 7.8%, adolescent idiopathic scoliosis 2.8% (P < 0.0001). Plastics were used more for early onset scoliosis [odds ratio (OR) 18.5, 95% confidence interval (CI): 8.5, 40.2; P < 0.001] and neuromuscular scoliosis [OR 29.2 (12.2, 69.9); P < 0.001] than adolescent idiopathic scoliosis. Plastics use was unrelated to practice size, setting, or geographic region (P ≥ 0.09). Respondents used plastics more often for spina bifida and underweight patients compared to all other indications (P < 0.001). Compared to orthopaedic management, drains were utilized more often by plastic surgery (85 vs. 21%, P = 0.06) and for longer durations (P = 0.001). Eighty-nine percent of surgeons felt plastics increased operative time (58 ±â€…37 min), and 34% felt it increased length of hospitalization. Surgeons who routinely utilize plastics were more likely to believe PMC decreases wound complications (P = 0.007). The perceived benefit of plastic surgery varies, highlighting equipoise among pediatric spine surgeons. An evidence-based guideline is needed to optimize utilization of plastics in pediatric spine surgery.

The Fate of The Broken Tether: How Do Curves Treated with Vertebral Body Tethering Behave After Tether Breakage?

STUDY DESIGN: Retrospective, Multicenter. OBJECTIVE: Assess curve progression and occurrence of revision surgery following tether breakage after vertebral body tethering (VBT). SUMMARY OF BACKGROUND DATA: Tether breakage after VBT is common with rates up to 50% reported. In these cases, it remains unknown whether the curve will progress or remain stable. METHODS: Adolescent and juvenile idiopathic scoliosis patients in a multicenter registry with ≥2 year-follow-up after VBT were reviewed. Broken tethers were listed as postoperative complications and identified by increased screw divergence of >5° on serial radiographs. Revision procedures and curve magnitude at subsequent visits were recorded. RESULTS: Of 186 patients who qualified for inclusion, 84 (45.2%) patients with tether breakage were identified with a mean age at VBT of 12.4±1.4 years and mean curve magnitude at index procedure of 51.8°±8.1°. Tether breakage occurred at a mean of 30.3±11.8 months and mean curve of 33.9°±13.2°. Twelve patients (12/84, 14.5%) underwent 13 revision procedures after VBT breakage, including 6 tether revisions and 7 conversions to fusion. All tether revisions occurred within 5 months of breakage identification. No patients with curves <35° after breakage underwent revision. Revision rate was greatest in skeletally immature (Risser 0-3) patients with curves ≥35° at time of breakage (Risser 0-3: 9/17, 53% vs. Risser 4-5: 3/23, 13%, P=0.01).Curves increased by 3.1° and 3.7° in the first and second year, respectively. By two years, 15/30 (50%) progressed >5° and 8/30 (26.7%) progressed greater than 10°. Overall, 66.7% (40/60) reached a curve magnitude >35° at their latest follow-up, and 14/60 (23.3%) reached a curve magnitude greater than 45°. Skeletal maturity did not affect curve progression after tether breakage (P>0.26), but time to rupture did (P=0.048). CONCLUSION: While skeletal immaturity and curve magnitude were not independently associated with curve progression, skeletally immature patients with curves ≥35° at time of rupture are most likely to undergo additional surgery. Most patients can expect progression at least 5° in the first two years after tether breakage, though longer-term behavior remains unknown. LEVEL OF EVIDENCE: III.

Practice-enhancing publications about the medication-use process in 2021.

DISCLAIMER: In an effort to expedite the publication of articles, AJHP is posting manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time. PURPOSE: This article identifies, prioritizes, and summarizes published literature on the medication-use process (MUP) from calendar year 2021 that can impact health-system pharmacy daily practice. The MUP is the foundational system that provides the framework for safe medication utilization within the healthcare environment. The MUP is defined in this article as having the following components: prescribing/transcribing, dispensing, administration, and monitoring, and monitoring/medication reconciliation. Articles evaluating at least one step of the MUP were assessed for their usefulness toward practice improvement. SUMMARY: A PubMed search was conducted in January 2022 for articles published in calendar year 2021 using targeted Medical Subject Headings (MeSH) keywords, and searches of the table of contents of selected pharmacy journals were conducted, providing a total of 7,178 articles. A thorough review identified 79 potentially practice-enhancing articles: 15 for prescribing/transcribing, 17 for dispensing, 4 for administration, 21 for monitoring, and 22 for monitoring/medication reconciliation. Ranking of the articles for importance by peers led to the selection of key articles from each category. The highest-ranked articles are briefly summarized, with a mention of their importance within health-system pharmacy. The other articles are listed for further review and evaluation. CONCLUSION: It is important to routinely review the published literature and to incorporate significant findings into daily practice. This article assists in identifying and summarizing the most impactful publications. Health-system pharmacists have an active role in improving the MUP in their institution, and awareness of the significant published studies can assist in changing practice at the institutional level.

Exploring Side Effects of Sublingual Immunotherapy: A Systemic Review and Meta-Analysis.

Objective: Sublingual immunotherapy (SLIT) has emerged as a potentially safe and convenient option for allergen immunotherapy for patients with inhalant allergy. Larger studies on the overall side effects and severe reactions anaphylaxis are still lacking. Study Design: Systematic review and meta-analysis. Setting: Author's review was completed in the University of Texas Medical Branch. Methods: A systematic review and meta-analysis of prospective clinical trials focusing on SLIT safety published from January 1, 2001, to December 31, 2021, was conducted. Results: Twenty-six studies were included with analysis of 7827 patients, representing over 2.7 million SLIT doses. All studies focused on single-antigen immunotherapy. The mean duration of treatment was 11.54 months. Local side effects were present in 40.83% of patients [95% confidence interval (CI) 24.78-57.96]. Systemic side effects were encountered in 1.09% of SLIT patients (95% CI 0.57-1.78). Anaphylaxis was reported in 0.13% of patients (95% CI 0.06-0.22). Discontinuation rates due to side effects were low, at 4.32% of patients (95% CI 3.28-5.49). Conclusion: This meta-analysis shows that single-antigen SLIT is well-tolerated, with overall low rates of systemic side effects including anaphylaxis. Although there is a high rate of minor local side effect, the treatment attrition during the first year is low. With growing allergy burden worldwide, SLIT is a convenient and economically feasible option for immunotherapy. Further work is needed to evaluate long-term safety and efficacy of single as well as multi-antigen SLIT, including quality of life assessments.

School Readiness Predictors of Early Academic Achievement in Children Born Very Preterm.

OBJECTIVE: This study examined associations of school readiness measures obtained before school entry with academic achievement at early school age in children born very preterm (VPT, gestational age ≤ 30 weeks) and children born full term (FT, GA ≥ 37 weeks). METHOD: The sample included 38 children born VPT and 30 born FT recruited at age 4 years and followed to early school age. Measures of readiness included tests of global cognition, executive function, motor abilities, and preacademic skills, as well as caregiver behavior ratings. Tests of math, reading, and spelling were administered to assess school-age achievement. Analyses that controlled for socioeconomic status and accounted for inclusion of siblings compared the groups on the achievement tests and identified measures of readiness related to school-age achievement. RESULTS: Achievement difficulties were more pronounced in the VPT group and associated with problems in multiple readiness domains. Effect sizes for these associations were largest for measures of spatial ability, executive function, and preacademic skills. Some associations remained significant when controlling for global cognitive ability at age 4 years, and others were significant only for the VPT group. CONCLUSION: Findings suggest that deficits on tests in multiple readiness domains assessed before school entry in children born VPT or FT are associated with early school-age achievement. The most pronounced readiness deficits in the VPT group at age 4 years were also among those most closely associated with later difficulties in achievement. Further research is needed to refine assessment of school readiness in children born VPT.

Computational identification of surface markers for isolating distinct subpopulations from heterogeneous cancer cell populations.

Intratumor heterogeneity reduces treatment efficacy and complicates our understanding of tumor progression. There is a pressing need to understand the functions of heterogeneous tumor cell subpopulations within a tumor, yet biological systems to study these processes in vitro are limited. With the advent of single-cell RNA sequencing (scRNA-seq), it has become clear that some cancer cell line models include distinct subpopulations. Heterogeneous cell lines offer a unique opportunity to study the dynamics and evolution of genetically similar cancer cell subpopulations in controlled experimental settings. Here, we present clusterCleaver, a computational package that uses metrics of statistical distance to identify candidate surface markers maximally unique to transcriptomic subpopulations in scRNA-seq which may be used for FACS isolation. clusterCleaver was experimentally validated using the MDA-MB-231 and MDA-MB-436 breast cancer cell lines. ESAM and BST2/tetherin were experimentally confirmed as surface markers which identify and separate major transcriptomic subpopulations within MDA-MB-231 and MDA-MB-436 cells, respectively. clusterCleaver is a computationally efficient and experimentally validated workflow for identification and enrichment of distinct subpopulations within cell lines which paves the way for studies on the coexistence of cancer cell subpopulations in well-defined in vitro systems.

Maternal Western-style diet programs skeletal muscle gene expression in lean adolescent Japanese macaque offspring.

Early-life exposure to maternal obesity or a maternal calorically dense Western-style diet (WSD) is strongly associated with a greater risk of metabolic diseases in offspring, most notably insulin resistance and metabolic dysfunction-associated steatotic liver disease (MASLD). Prior studies in our well-characterized Japanese macaque model demonstrated that offspring of dams fed a WSD, even when weaned onto a control (CTR) diet, had reductions in skeletal muscle mitochondrial metabolism and increased skeletal muscle insulin resistance compared to offspring of dams on CTR diet. In the current study, we employed a nested design to test for differences in gene expression in skeletal muscle from lean 3-year-old adolescent offspring from dams fed a maternal WSD in both the presence and absence of maternal obesity or lean dams fed a CTR diet. We included offspring weaned to both a WSD or CTR diet to further account for differences in response to post-weaning diet and interaction effects between diets. Overall, we found that a maternal WSD fed to dams during pregnancy and lactation was the principal driver of differential gene expression (DEG) in offspring muscle at this time point. We identified key gene pathways important in insulin signaling including PI3K-Akt and MAP-kinase, regulation of muscle regeneration, and transcription-translation feedback loops, in both male and female offspring. Muscle DEG showed no measurable difference between offspring of obese dams on WSD compared to those of lean dams fed WSD. A post-weaning WSD effected offspring transcription only in individuals from the maternal CTR diet group but not in maternal WSD group. Collectively, we identify that maternal diet composition has a significant and lasting impact on offspring muscle transcriptome and influences later transcriptional response to WSD in muscle, which may underlie the increased metabolic disease risk in offspring.

Changes in brain functional connectivity and muscle strength independent of elbow flexor atrophy following upper limb immobilization in young females.

Muscle disuse induces a decline in muscle strength that exceeds the rate and magnitude of muscle atrophy, suggesting that factors beyond the muscle contribute to strength loss. The purpose of this study was to characterize changes in the brain and neuromuscular system in addition to muscle size following upper limb immobilization in young females. Using a within-participant, unilateral design, 12 females (age: 20.6 ± 2.1 years) underwent 14 days of upper arm immobilization using an elbow brace and sling. Bilateral measures of muscle strength (isometric and isokinetic dynamometry), muscle size (magnetic resonance imaging), voluntary muscle activation capacity, corticospinal excitability, cortical thickness and resting-state functional connectivity were collected before and after immobilization. Immobilization induced a significant decline in isometric elbow flexion (-21.3 ± 19.2%, interaction: P = 0.0440) and extension (-19.9 ± 15.7%, interaction: P = 0.0317) strength in the immobilized arm only. There was no significant effect of immobilization on elbow flexor cross-sectional area (CSA) (-1.2 ± 2.4%, interaction: P = 0.466), whereas elbow extensor CSA decreased (-2.9 ± 2.9%, interaction: P = 0.0177) in the immobilized arm. Immobilization did not differentially alter voluntary activation capacity, corticospinal excitability, or cortical thickness (P > 0.05); however, there were significant changes in the functional connectivity of brain regions related to movement planning and error detection (P < 0.05). This study reveals that elbow flexor strength loss can occur in the absence of significant elbow flexor muscle atrophy, and that the brain represents a site of functional adaptation in response to upper limb immobilization in young females.

The elucidation of species-specific receptor pharmacology: a case study using subtype selective para- and meta-carborane estrogen receptor agonists.

Estrogen receptors are essential pharmacological targets for treating hormonal disorders and estrogen-dependent malignancies. Selective activation of estrogen receptor (ER) ß is hypothesized to provide therapeutic benefit with reduced risk of unwanted estrogenic side-effects associated with ERα activity. However, activating ERß without activating α is challenging due to the high sequence and structural homology between the receptor subtypes. We assessed the impact of structural modifications to the parent compound OSU-ERß-12 on receptor subtype binding selectivity using cell-free binding assays. Functional selectivity was evaluated by transactivation in HEK-293 cells overexpressing human or murine estrogen receptors. In vivo selectivity was examined through the uterotrophic effects of the analogs after oral administration in estrogen-naïve female mice. Furthermore, we evaluated the in vivo pharmacokinetics of the analogs following single dose IV and oral administration. Regarding selectivity, a single compound exhibited greater functional selectivity than OSU-ERß-12 for human ERß. However, like others in the meta-carborane series, its poor in vivo pharmacokinetics limit its suitability for further development. Surprisingly, and at odds with their pharmacokinetic and in vitro human activity data, most analogs potently induced uterotrophic effects in estrogen-naïve female mice. Further investigation of activity in HEK293 cells expressing murine estrogen receptors revealed species-specific differences in the ER-subtype selectivity of these analogs. Our findings highlight species-specific receptor pharmacology and the challenges it poses to characterizing developmental therapeutics in preclinical species. Significance Statement This study investigates para- and meta-substituted carborane analogs targeting estrogen receptors, revealing the greater selectivity of carborane analogs for human ERß compared to the mouse homolog. These findings shed light on the intricacies of using preclinical species in drug development to predict human pharmacology. The report also provides insights for the refinement and optimization of carborane analogs as potential therapeutic agents for estrogen-related disease states.

The surgical learning curve for percutaneous Zadek osteotomy for treatment of insertional achilles tendinopathy.

INTRODUCTION: The Zadek Osteotomy has been described as an effective technique for the treatment of insertional Achilles tendinopathy. Recently, this strategy has been modified using minimally invasive techniques. A learning curve has been observed in many minimally invasive procedures in foot and ankle surgery. This retrospective study first intended to evaluate if there is a learning curve associated with the percutaneous Zadek Osteotomy. Further, if a learning curve was observed, we planned to assess the data for associated changes in complications and postoperative outcomes. METHODS: A retrospective analysis of 98 patients who underwent percutaneous Zadek Osteotomy was performed. Patient charts were reviewed for operative times, complications, union rates, and Foot Function Index (FFI) and Visual Analogue Scale (VAS) scores. Analysis of variance was utilized to assess for differences between groups of cases. RESULTS: Patients included 61 females and 37 males. Mean age was 51.28 ± 11.12 (range 28-81) years. Mean follow-up time was 42.07 ± 12.99 (range 24-65) months. Significant increases in operative times were observed in cases 1-14 when compared to cases 15-98 (p < 0.001). Improvements in FFI and VAS scores were observed at final follow-up within each case group (p < 0.001); there were no differences detected in FFI or VAS scores between groups of cases. There was no difference detected in number of complications between intervals of cases. CONCLUSION: A learning curve was observed for the percutaneous Zadek Osteotomy, which was overcome around case 14. This learning curve was only observed in terms of procedure length. A surgeon's level of inexperience with the technique does not appear to affect functional outcomes, nonunion, or need for revision. LEVEL OF EVIDENCE IV: Data will not be deposited in a repository.

Characterization of UbiA terpene synthases with a precursor overproduction system in Escherichia coli.

Expression and purification of membrane-bound proteins remains a challenge and limits enzymology efforts, contributing to a substantial knowledge gap in the biochemical functions of many proteins found in nature. Accordingly, the study of bacterial UbiA terpene synthases (TSs) has been limited due to the experimental hurdles required to purify active enzymes for characterization in vitro. Previous work employed the use of microsomes or crude membrane fractions to test enzyme activity; however, these methods can be labor intensive, require access to an ultracentrifuge, or may not be suitable for all membrane-bound TSs. We detail here an alternative strategy for the in vivo expression and biochemical characterization of the membrane associated UbiA TSs by employing a precursor overproduction system in Escherichia coli.