Morphometric Analysis of Spina Bifida after Fetal Repair Shows New Subtypes with Associated Outcomes.

Importance: The binary classification of spina bifida lesions as myelomeningocele (with sac) or myeloschisis (without sac) belies a spectrum of morphologies, which have not been correlated to clinical characteristics and outcomes. Objective: To characterize spina bifida lesion types and correlate them with preoperative presentation and postoperative outcomes. Design: Secondary analysis of images and videos obtained during fetoscopic spina bifida repair surgery from 2020-2023. Setting: Fetal surgery was performed at a quaternary care center. Participants: A prospective cohort of patients referred for fetal spina bifida underwent fetoscopic repair under an FDA-approved protocol. Of 60 lesions repaired, 57 had available images and were included in the analysis. Interventions or Exposures: We evaluated lesion morphology on high-resolution intraoperative images and videos to categorize lesions based on placode exposure and nerve root stretching. Main Outcomes and Measures: The reproducibility of the lesion classification was assessed via Kappa interrater agreement. Preoperative characteristics analyzed include ventricle size, tonsillar herniation level, lower extremities movement, and lesion dimensions. Outcomes included surgical time, need for patch for skin closure, gestational age at delivery, preterm premature rupture of membranes (PPROM), and neonatal cerebrospinal fluid (CSF) diversion. Results: We distinguished five lesion types that differ across a range of sac sizes, nerve root stretching, and placode exposure, with 93% agreement between examiners (p<0.001). Fetal characteristics at preoperative evaluation differed significantly by lesion type, including lesion volume (p<0.001), largest ventricle size (p=0.008), tonsillar herniation (p=0.005), and head circumference (p=0.03). Lesion level, talipes, and lower extremities movement did not differ by type. Surgical and perinatal outcomes differed by lesion type, including need for patch skin closure (p<0.001), gestational age at delivery (p=0.01), and NICU length of stay (p<0.001). PPROM, CSF leakage at birth, and CSF diversion in the NICU did not differ between lesion groups. Linear regression associated severity of ventriculomegaly with lesion type, but not with tonsillar herniation level. Conclusions and Relevance: There is a distinct phenotypic spectrum in open spina bifida with differential baseline presentation and outcomes. Severity of ventriculomegaly is associated with lesion type, rather than tonsillar herniation level. Our findings expand the classification of spina bifida to reveal a spectrum that warrants further study.

Biotin labeling allows for post-transfusion functional assessment of stored human platelets in mice.

BACKGROUND: Platelet radiolabeling with radioisotopes is currently used for human platelet recovery and survival studies. Biotinylation enables ex vivo post-transfusion platelet function testing. Whether platelet biotinylation itself affects platelet function is controversial. STUDY DESIGN AND METHODS: Platelet concentrates from healthy humans were stored for 6 days. Samples were obtained at 1 or 2 and 6 days, and platelets were labeled following a radiolabeling protocol using saline instead of radioactive indium-111 (sham radiolabeling [sham-RL]). Alternatively, a newly developed biotinylation protocol, a washing protocol, or an unmanipulated control sample were used. Platelet function was assessed by flow cytometry after stimulation with platelet agonists and labeling of platelets with platelet activation markers. To test whether platelets can be activated after transfusion, labeled platelets were transfused into nonobese diabetic/severe combined immunodeficiency mice, and samples were obtained 1 h after transfusion. RESULTS: The activation profile of biotinylated platelets was comparable to sham-RL platelets before transfusion except for significantly less α-degranulation and more phosphatidyl serine exposure on storage day 1/2. There was no significant difference between sham-RL and biotinylated platelets on storage day 6. Sham-RL and biotinylated platelets were significantly less activatable than washed and unmanipulated control platelets. After transfusion, the activation profile of biotinylated platelets was largely indistinguishable from unmanipulated ones. DISCUSSION: The decrease in activation level in biotinylated platelets we and others observed appears mainly due to the physical manipulation during the labeling process. In conclusion, biotinylated platelets allow for post-transfusion function assessment, a major advantage over radiolabeling.

Perceptions and Attitudes Related to Driving after Cannabis Use in Canadian and US Adults.

BACKGROUND: This study examined the risk perceptions related to driving after cannabis use (DACU) among Canadian and US adults who used cannabis in the past six months. METHODS: Perceptions of danger, normative beliefs, perceived likelihood of negative consequences, and other driving-related variables were collected via online surveys in Canadian (n = 158; 50.0% female, 84.8% White, mean age = 32.73 years [SD = 10.61]) and US participants (n = 678; 50.9% female, 73.6% White, mean age = 33.85 years [SD = 10.12]). Driving cognitions and DACU quantity/frequency were compared between samples using univariate analyses of variance, and Spearman's (ρ) correlations were performed to examine associations between driving cognitions and DACU quantity/frequency. RESULTS: The two samples did not significantly differ in self-reported level of cannabis use, lifetime quantity of DACU, or the number of times they drove within two hours of cannabis use in the past three months (Ps > .12). Compared to US participants, Canadians perceived driving within two hours of cannabis use as more dangerous (P < 0.001, ηp2 = 0.013) and reported more of their friends would disapprove of DACU (P = 0.03, ηp2 = 0.006). There were no differences in the number of friends who would refuse to ride with a driver who had used cannabis (P = 0.15) or the perceived likelihood of negative consequences (Ps > 0.07). More favorable perceptions were significantly correlated with greater lifetime DACU and driving within two hours of use (ρ = 0.25-0.53, Ps < 0.01). CONCLUSIONS: These findings reveal differences in distal risk factors for DACU between Canada and the US and may inform prevention efforts focusing on perceptions of risk and social acceptance of DACU.

Evaluating protein cross-linking as a therapeutic strategy to stabilize SOD1 variants in a mouse model of familial ALS.

Mutations in the gene encoding Cu-Zn superoxide dismutase 1 (SOD1) cause a subset of familial amyotrophic lateral sclerosis (fALS) cases. A shared effect of these mutations is that SOD1, which is normally a stable dimer, dissociates into toxic monomers that seed toxic aggregates. Considerable research effort has been devoted to developing compounds that stabilize the dimer of fALS SOD1 variants, but unfortunately, this has not yet resulted in a treatment. We hypothesized that cyclic thiosulfinate cross-linkers, which selectively target a rare, 2 cysteine-containing motif, can stabilize fALS-causing SOD1 variants in vivo. We created a library of chemically diverse cyclic thiosulfinates and determined structure-cross-linking-activity relationships. A pre-lead compound, "S-XL6," was selected based upon its cross-linking rate and drug-like properties. Co-crystallographic structure clearly establishes the binding of S-XL6 at Cys 111 bridging the monomers and stabilizing the SOD1 dimer. Biophysical studies reveal that the degree of stabilization afforded by S-XL6 (up to 24°C) is unprecedented for fALS, and to our knowledge, for any protein target of any kinetic stabilizer. Gene silencing and protein degrading therapeutic approaches require careful dose titration to balance the benefit of diminished fALS SOD1 expression with the toxic loss-of-enzymatic function. We show that S-XL6 does not share this liability because it rescues the activity of fALS SOD1 variants. No pharmacological agent has been proven to bind to SOD1 in vivo. Here, using a fALS mouse model, we demonstrate oral bioavailability; rapid engagement of SOD1G93A by S-XL6 that increases SOD1G93A's in vivo half-life; and that S-XL6 crosses the blood-brain barrier. S-XL6 demonstrated a degree of selectivity by avoiding off-target binding to plasma proteins. Taken together, our results indicate that cyclic thiosulfinate-mediated SOD1 stabilization should receive further attention as a potential therapeutic approach for fALS.

Pharmacodynamic effects of the PARP inhibitor talazoparib (MDV3800, BMN 673) in patients with BRCA-mutated advanced solid tumors.

PURPOSE: Talazoparib is an inhibitor of the poly (ADP-ribose) polymerase (PARP) family of enzymes and is FDA-approved for patients with (suspected) deleterious germline BRCA1/2-mutated, HER2­negative, locally advanced or metastatic breast cancer. Because knowledge of the pharmacodynamic (PD) effects of talazoparib in patients has been limited to studies of PARP enzymatic activity (PARylation) in peripheral blood mononuclear cells, we developed a study to assess tumoral PD response to talazoparib treatment (NCT01989546). METHODS: We administered single-agent talazoparib (1 mg/day) orally in 28-day cycles to adult patients with advanced solid tumors harboring (suspected) deleterious BRCA1 or BRCA2 mutations. The primary objective was to examine the PD effects of talazoparib; the secondary objective was to determine overall response rate (ORR). Tumor biopsies were mandatory at baseline and post-treatment on day 8 (optional at disease progression). Biopsies were analyzed for PARylation, DNA damage response (γH2AX), and epithelial‒mesenchymal transition. RESULTS: Nine patients enrolled in this trial. Four of six patients (67%) evaluable for the primary PD endpoint exhibited a nuclear γH2AX response on day 8 of treatment, and five of six (83%) also exhibited strong suppression of PARylation. A transition towards a more mesenchymal phenotype was seen in 4 of 6 carcinoma patients, but this biological change did not affect γH2AX or PAR responses. The ORR was 55% with the five partial responses lasting a median of six cycles. CONCLUSION: Intra-tumoral DNA damage response and inhibition of PARP enzymatic activity were confirmed in patients with advanced solid tumors harboring BRCA1/2 mutations after 8 days of talazoparib treatment.

Azithromycin reduces hemoglobin-induced innate neuroimmune activation.

Neonatal intraventricular hemorrhage (IVH) releases blood products into the lateral ventricles and brain parenchyma. There are currently no medical treatments for IVH and surgery is used to treat a delayed effect of IVH, post-hemorrhagic hydrocephalus. However, surgery is not a cure for intrinsic brain injury from IVH, and is performed in a subacute time frame. Like many neurological diseases and injuries, innate immune activation is implicated in the pathogenesis of IVH. Innate immune activation is a pharmaceutically targetable mechanism to reduce brain injury and post-hemorrhagic hydrocephalus after IVH. Here, we tested the macrolide antibiotic azithromycin, which has immunomodulatory properties, to reduce innate immune activation in an in vitro model of microglial activation using the blood product hemoglobin (Hgb). We then utilized azithromycin in our in vivo model of IVH, using intraventricular blood injection into the lateral ventricle of post-natal day 5 rat pups. In both models, azithromycin modulated innate immune activation by several outcome measures including mitochondrial bioenergetic analysis, cytokine expression and flow cytometric analysis. This suggests that azithromycin, which is safe for neonates, could hold promise for modulating innate immune activation after IVH.

Comparison of 2 Robotic Systems for Pediatric Stereoelectroencephalography Implantation.

BACKGROUND: Stereoelectroencephalography (SEEG) remains critical in guiding epilepsy surgery. Robot-assisted techniques have shown promise in improving SEEG implantation outcomes but have not been directly compared. In this single-institution series, we compared ROSA and Stealth AutoGuide robots in pediatric SEEG implantation. METHODS: We retrospectively reviewed 21 sequential pediatric SEEG implantations consisting of 6 ROSA and 15 AutoGuide procedures. We determined mean operative time, time per electrode, root mean square (RMS) registration error, and surgical complications. Three-dimensional radial distances were calculated between each electrode's measured entry and target points with respective errors from the planned trajectory line. RESULTS: Mean overall/per electrode operating time was 73.5/7.5 minutes for ROSA and 126.1/10.9 minutes for AutoGuide (P = 0.030 overall, P = 0.082 per electrode). Mean RMS registration error was 0.77 mm (0.55-0.93 mm) for ROSA and 0.6 mm (0.2-1.0 mm) for AutoGuide (P = 0.26). No procedures experienced complications. The mean radial (entry point error was 1.23 ± 0.11 mm for ROSA and 2.65 ± 0.12 mm for AutoGuide (P < 0.001), while the mean radial target point error was 1.86 ± 0.15 mm for ROSA and 3.25 ± 0.16 mm for AutoGuide (P < 0.001). CONCLUSIONS: Overall operative time was greater for AutoGuide procedures, although there was no statistically significant difference in time per electrode. Both systems are highly accurate with no significant RMS error difference. While the ROSA robot yielded significantly lower entry and target point errors, both robots are safe and reliable for deep electrode insertion in pediatric epilepsy.

Examining the effect of cannabis cues on cannabis demand in sleep, driving, and typical drug-use contexts.

PURPOSE: Given the expanding legal cannabis market in the U.S., it is vital to understand how context impacts cannabis use. Therefore, we explored the effect of cannabis cues and cannabis-use context on cannabis demand in 79 adults who reported smoking cannabis at least weekly. METHODS: Participants completed a single laboratory session consisting of four hypothetical marijuana purchase tasks (MPTs) involving either a typical use situation or a driving or sleep context. The MPTs were alternated with exposure to cannabis or neutral picture cues based on block randomization by gender. RESULTS: Cannabis cues increased self-reported craving for cannabis (p =.044) but did not significantly alter demand (ps =0.093-0.845). In the driving context, participants demonstrated a significant reduction in cannabis demand, indicated by lower intensity (p <0.001), Omax (p <0.001), and Pmax (p <0.001), breakpoint (p =.003), and higher α (p <0.001). The sleep context was associated with significantly greater α (p <0.006) but nonsignificant effects for other indices (ps =0.123-0.707). Finally, cannabis cues increased Omax (p =.013) and breakpoint (p =.035) in the sleep context but not in the typical-use context. CONCLUSIONS: These findings suggest that cannabis-use behavior is sensitive to contingencies surrounding driving after cannabis use and may also be sensitive to sleep contexts in the presence of cannabis cues. Since this is the first study to examine driving and sleep contexts, we caution against drawing broad conclusions until future research is conducted to replicate these findings.

Adaptation of commodity purchase tasks to identify substitutable substance-free alternative activities for alcohol use.

Behavioral economic frameworks emphasize the importance of contextual influences on alcohol use; therefore, identifying relative demand for alcohol versus other commodities is of importance. Cross-commodity purchase tasks allow participants to make choices across multiple concurrently available commodities and can thereby pinpoint interactions among those commodities. These tasks may help identify relevant substance-free alternative activities to target in alcohol treatment by determining whether the activity functions as a substitute for alcohol use. While substance-free activity promotion is a promising behavioral component of alcohol interventions, no research to-date has used behavioral economic methods to assess the substitutability of alternative activities for alcohol use. The present studies were preliminary assessments of novel single- and cross-commodity purchase tasks of various alternative activities (e.g., exercise, hobbies, civic involvement). Participants in Study 1 recruited from Amazon's Mechanical Turk (n = 110) were administered a series of novel activity purchase tasks and an alcohol purchase task. Results showed excellent fit of the exponential demand equation to activity purchase task data and provided initial support for adaptation of purchase task methodology to alternative activity demand. In Study 2, participants recruited from Amazon's Mechanical Turk (n = 108) were administered both single-commodity and cross-commodity purchase tasks of alcohol and exercise. While most participants demonstrate independent consumption of alcohol and exercise, a subset of participants substituted exercise for alcohol as indicated by quantitative cross-price elasticity indices. These response patterns highlight the importance of individual differences and hold implications for recovery efforts that promote alternative activity engagement and public policy. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Shotgun Kinetic Target-Guided Synthesis Approach Enables the Discovery of Small-Molecule Inhibitors against Pathogenic Free-Living Amoeba Glucokinases.

Pathogenic free-living amoebae (pFLA) can cause life-threatening central nervous system (CNS) infections and warrant the investigation of new chemical agents to combat the rise of infection from these pathogens. Naegleria fowleri glucokinase (NfGlck), a key metabolic enzyme involved in generating glucose-6-phosphate, was previously identified as a potential target due to its limited sequence similarity with human Glck (HsGlck). Herein, we used our previously demonstrated multifragment kinetic target-guided synthesis (KTGS) screening strategy to identify inhibitors against pFLA glucokinases. Unlike the majority of previous KTGS reports, our current study implements a "shotgun" approach, where fragments were not biased by predetermined binding potentials. The study resulted in the identification of 12 inhibitors against 3 pFLA glucokinase enzymes─NfGlck, Balamuthia mandrillaris Glck (BmGlck), and Acanthamoeba castellanii Glck (AcGlck). This work demonstrates the utility of KTGS to identify small-molecule binders for biological targets where resolved X-ray crystal structures are not readily accessible.

Atezolizumab for Advanced Alveolar Soft Part Sarcoma.

BACKGROUND: Alveolar soft part sarcoma (ASPS) is a rare soft-tissue sarcoma with a poor prognosis and no established therapy. Recently, encouraging responses to immune checkpoint inhibitors have been reported. METHODS: We conducted an investigator-initiated, multicenter, single-group, phase 2 study of the anti-programmed death ligand 1 (PD-L1) agent atezolizumab in adult and pediatric patients with advanced ASPS. Atezolizumab was administered intravenously at a dose of 1200 mg (in patients ≥18 years of age) or 15 mg per kilogram of body weight with a 1200-mg cap (in patients <18 years of age) once every 21 days. Study end points included objective response, duration of response, and progression-free survival according to Response Evaluation Criteria in Solid Tumors (RECIST), version 1.1, as well as pharmacodynamic biomarkers of multistep drug action. RESULTS: A total of 52 patients were evaluated. An objective response was observed in 19 of 52 patients (37%), with 1 complete response and 18 partial responses. The median time to response was 3.6 months (range, 2.1 to 19.1), the median duration of response was 24.7 months (range, 4.1 to 55.8), and the median progression-free survival was 20.8 months. Seven patients took a treatment break after 2 years of treatment, and their responses were maintained through the data-cutoff date. No treatment-related grade 4 or 5 adverse events were recorded. Responses were noted despite variable baseline expression of programmed death 1 and PD-L1. CONCLUSIONS: Atezolizumab was effective at inducing sustained responses in approximately one third of patients with advanced ASPS. (Funded by the National Cancer Institute and others; ClinicalTrials.gov number, NCT03141684.).

NLRP3 selectively drives IL-1ß secretion by Pseudomonas aeruginosa infected neutrophils and regulates corneal disease severity.

Macrophages infected with Gram-negative bacteria expressing Type III secretion system (T3SS) activate the NLRC4 inflammasome, resulting in Gasdermin D (GSDMD)-dependent, but GSDME independent IL-1ß secretion and pyroptosis. Here we examine inflammasome signaling in neutrophils infected with Pseudomonas aeruginosa strain PAO1 that expresses the T3SS effectors ExoS and ExoT. IL-1ß secretion by neutrophils requires the T3SS needle and translocon proteins and GSDMD. In macrophages, PAO1 and mutants lacking ExoS and ExoT (ΔexoST) require NLRC4 for IL-1ß secretion. While IL-1ß release from ΔexoST infected neutrophils is also NLRC4-dependent, infection with PAO1 is instead NLRP3-dependent and driven by the ADP ribosyl transferase activity of ExoS. Genetic and pharmacologic approaches using MCC950 reveal that NLRP3 is also essential for bacterial killing and disease severity in a murine model of P. aeruginosa corneal infection (keratitis). Overall, these findings reveal a function for ExoS ADPRT in regulating inflammasome subtype usage in neutrophils versus macrophages and an unexpected role for NLRP3 in P. aeruginosa keratitis.

Can Craniosynostosis be Diagnosed on Physical Examination? A Retrospective Review.

Craniosynostosis is a developmental craniofacial defect in which one or more sutures of the skull fuse together prematurely. Uncorrected craniosynostosis may have serious complications including elevated intracranial pressure, developmental delay, and blindness. Proper diagnosis of craniosynostosis requires a physical examination of the head with assessment for symmetry and palpation of sutures for prominence. Often, if craniosynostosis is suspected, computed tomography (CT) imaging will be obtained. Recent literature has posited that this is unnecessary. This study aims to address whether physical examination alone is sufficient for the diagnosis and treatment planning of single suture craniosynostosis. Between 2015 and 2022, the Divisions of Pediatric Neurosurgery and Pediatric Plastic Surgery at UTHealth Houston evaluated 140 children under 36 months of age with suspected craniosynostosis by physical examination and subsequently ordered CT imaging for preoperative planning. Twenty-three patients received a clinical diagnosis of multi-sutural or syndromic craniosynostosis that was confirmed by CT. One hundred seventeen patients were diagnosed with single suture craniosynostosis on clinical examination and follow-up CT confirmed suture fusion in 109 (93.2%) patients and identified intracranial anomalies in 7 (6.0%) patients. These patients underwent surgical correction. Eight (6.8%) patients showed no evidence of craniosynostosis on CT imaging. Treatment for patients without fused sutures included molding helmets and observation alone. This evidence suggests that physical examination alone may be inadequate to accurately diagnose single suture synostosis, and surgery without preoperative CT evaluation could lead to unindicated procedures.

Innate immune activation and white matter injury in a rat model of neonatal intraventricular hemorrhage are dependent on developmental stage.

BACKGROUND: Inflammation and white matter injury are consequences of neonatal intraventricular hemorrhage (IVH). Both white matter and the neuroimmune system are developing during the time which IVH occurs and its consequences develop. IVH has been studied in many different animal models; however, the effects of IVH occurring at different developmental time points in the same model have not been examined. Understanding how the timing of IVH affects outcome may provide important insights into both IVH pathophysiology and innate immune development. METHODS: We used intraventricular injection of lysed whole blood to model neonatal IVH in postnatal day (P)2 and P5 rats. Flow cytometry was used to detect innate immune activation. MRI was used to screen animals for the development of increased ventricular size. Immunohistochemistry for myelin basic protein was used to quantify white matter and corpus callosum thickness. RESULTS: P5 animals exhibited significant increases in several measures of classically pro-inflammatory innate immune activation that P2 animals did not. Animals with IVH induced at P5 also developed ventricular enlargement visible on MRI whereas animals with IVH induced at P2 did not. On histological analysis, there were no significant effects of IVH in P2 animals, but IVH in P5 animals reduced white matter labeling and corpus callosum thickness. CONCLUSIONS: IVH induces a strong innate inflammatory response in P5 as well as changes in ventricular size and reduction of white matter. P2 animals do not exhibit significant changes in innate immune activation or white matter structure after IVH. This suggests that white matter pathology from IVH is due in part to innate immune activation; and that the developmental stage of the innate immune system is a key determinant of IVH pathology.

Reliability and validity of behavioral-economic measures: A review and synthesis of discounting and demand.

This review sought to synthesize the literature on the reliability and validity of behavioral-economic measures of demand and discounting in human research, introduce behavioral-economic research methodologies for studying addictive behaviors, discuss gaps in the current literature, and review areas for future research. A total of 34 studies was included in this review. The discounting literature showed similar responding regardless of whether hypothetical or actual outcomes were used, though people tended to discount the outcome presented first more steeply, suggesting order effects. Although delay-discounting measures seem to show temporal stability, exceptions were found for probability- and experiential-discounting tasks. The demand literature also demonstrated similar responding regardless of outcome type; however, some demand indices showed exceptions. Randomized price sequences tended to show modest increases in Omax and α and modestly higher rates of inconsistent or nonsystematic responses compared with sequential price sequences. Demand indices generally showed temporal stability, although the stability was weaker the larger the time interval between test sessions. Future studies would benefit by examining addictive commodities beyond alcohol, nicotine, and money; examining temporal stability over longer time intervals; using larger delays in discounting tasks; and using larger sample sizes.

Streptothricin F is a bactericidal antibiotic effective against highly drug-resistant gram-negative bacteria that interacts with the 30S subunit of the 70S ribosome.

The streptothricin natural product mixture (also known as nourseothricin) was discovered in the early 1940s, generating intense initial interest because of excellent gram-negative activity. Here, we establish the activity spectrum of nourseothricin and its main components, streptothricin F (S-F, 1 lysine) and streptothricin D (S-D, 3 lysines), purified to homogeneity, against highly drug-resistant, carbapenem-resistant Enterobacterales (CRE) and Acinetobacter baumannii. For CRE, the MIC50 and MIC90 for S-F and S-D were 2 and 4 µM, and 0.25 and 0.5 µM, respectively. S-F and nourseothricin showed rapid, bactericidal activity. S-F and S-D both showed approximately 40-fold greater selectivity for prokaryotic than eukaryotic ribosomes in in vitro translation assays. In vivo, delayed renal toxicity occurred at >10-fold higher doses of S-F compared with S-D. Substantial treatment effect of S-F in the murine thigh model was observed against the otherwise pandrug-resistant, NDM-1-expressing Klebsiella pneumoniae Nevada strain with minimal or no toxicity. Cryo-EM characterization of S-F bound to the A. baumannii 70S ribosome defines extensive hydrogen bonding of the S-F steptolidine moiety, as a guanine mimetic, to the 16S rRNA C1054 nucleobase (Escherichia coli numbering) in helix 34, and the carbamoylated gulosamine moiety of S-F with A1196, explaining the high-level resistance conferred by corresponding mutations at the residues identified in single rrn operon E. coli. Structural analysis suggests that S-F probes the A-decoding site, which potentially may account for its miscoding activity. Based on unique and promising activity, we suggest that the streptothricin scaffold deserves further preclinical exploration as a potential therapeutic for drug-resistant, gram-negative pathogens.

Innate immune activation and white matter injury in a rat model of neonatal intraventricular hemorrhage are dependent on developmental stage.

Background: Inflammation and white matter injury are consequences of neonatal intraventricular hemorrhage (IVH). Both white matter and the neuroimmune system are developing during which IVH and its consequences occur. IVH has been studied in many different animal models; however, the effects of IVH occurring at different developmental time points in the same model has not been examined. Examining how the timing of IVH affects the ultimate outcome of IVH may provide important insights into IVH pathophysiology. Methods: We used intraventricular injection of lysed whole blood to model neonatal IVH in postnatal day (P)2 and P5 rats. Flow cytometry was used to detect innate immune activation. MRI was used to screen animals for the development of increased ventricular size. Immunohistochemistry for myelin basic protein was used to assess white matter pathology. Results: The acute response of the innate immune system at these time points differed, with P5 animals exhibiting significant increases in several measures of classically pro-inflammatory innate immune activation that P2 animals did not. Animals with IVH induced at P5 also developed ventricular enlargement visible on MRI whereas animals with IVH induced at P2 did not. On histological analysis, there were no significant effects of IVH in P2 animals, but IVH in P5 animals induced a reduction in several measures of white matter integrity. Conclusions: IVH induces a strong innate inflammatory response in P5 animals that correlates with changes in ventricular size and white matter. P2 animals did not exhibit any significant changes in innate immune activation or white matter structure after IVH. This suggests that the white matter pathology from IVH is due in part to innate immune activation; and that the developmental stage of the innate immune system is a key determinant of IVH pathology.

Pyroptosis in neutrophils: Multimodal integration of inflammasome and regulated cell death signaling pathways.

Pyroptosis is a proinflammatory mode of lytic cell death mediated by accumulation of plasma membrane (PM) macropores composed of gasdermin-family (GSDM) proteins. It facilitates two major functions in innate immunity: (i) elimination of intracellular replicative niches for pathogenic bacteria; and (ii) non-classical secretion of IL-1 family cytokines that amplify host-beneficial inflammatory responses to microbial infection or tissue damage. Physiological roles for gasdermin D (GSDMD) in pyroptosis and IL-1ß release during inflammasome signaling have been extensively characterized in macrophages. This involves cleavage of GSDMD by caspase-1 to generate GSDMD macropores that mediate IL-1ß efflux and progression to pyroptotic lysis. Neutrophils, which rapidly accumulate in large numbers at sites of tissue infection or damage, become the predominant local source of IL-1ß in coordination with their potent microbiocidal capacity. Similar to macrophages, neutrophils express GSDMD and utilize the same spectrum of diverse inflammasome platforms for caspase-1-mediated cleavage of GSDMD. Distinct from macrophages, neutrophils possess a remarkable capacity to resist progression to GSDMD-dependent pyroptotic lysis to preserve their viability for efficient microbial killing while maintaining GSDMD-dependent mechanisms for export of bioactive IL-1ß. Rather, neutrophils employ cell-specific mechanisms to conditionally engage GSDMD-mediated pyroptosis in response to bacterial pathogens that use neutrophils as replicative niches. GSDMD and pyroptosis have also been mechanistically linked to induction of NETosis, a signature neutrophil pathway that expels decondensed nuclear DNA into extracellular compartments for immobilization and killing of microbial pathogens. This review summarizes a rapidly growing number of recent studies that have produced new insights, unexpected mechanistic nuances, and some controversies regarding the regulation of, and roles for, neutrophil inflammasomes, pyroptosis, and GSDMs in diverse innate immune responses.

Metabolic reprogramming underlies cavefish muscular endurance despite loss of muscle mass and contractility.

Physical inactivity is a scourge to human health, promoting metabolic disease and muscle wasting. Interestingly, multiple ecological niches have relaxed investment into physical activity, providing an evolutionary perspective into the effect of adaptive physical inactivity on tissue homeostasis. One such example, the Mexican cavefish Astyanax mexicanus, has lost moderate-to-vigorous activity following cave colonization, reaching basal swim speeds ~3.7-fold slower than their river-dwelling counterpart. This change in behavior is accompanied by a marked shift in body composition, decreasing total muscle mass and increasing fat mass. This shift persisted at the single muscle fiber level via increased lipid and sugar accumulation at the expense of myofibrillar volume. Transcriptomic analysis of laboratory-reared and wild-caught cavefish indicated that this shift is driven by increased expression of pparγ-the master regulator of adipogenesis-with a simultaneous decrease in fast myosin heavy chain expression. Ex vivo and in vivo analysis confirmed that these investment strategies come with a functional trade-off, decreasing cavefish muscle fiber shortening velocity, time to maximal force, and ultimately maximal swimming speed. Despite this, cavefish displayed a striking degree of muscular endurance, reaching maximal swim speeds ~3.5-fold faster than their basal swim speeds. Multi-omic analysis suggested metabolic reprogramming, specifically phosphorylation of Pgm1-Threonine 19, as a key component enhancing cavefish glycogen metabolism and sustained muscle contraction. Collectively, we reveal broad skeletal muscle changes following cave colonization, displaying an adaptive skeletal muscle phenotype reminiscent to mammalian disuse and high-fat models while simultaneously maintaining a unique capacity for sustained muscle contraction via enhanced glycogen metabolism.

Next-day responsibilities attenuate demand for alcohol among a crowdsourced sample of community adults.

While several studies have examined how class time and internship responsibilities impact demand for alcohol in undergraduate samples, no study has examined this question using more universally applicable responsibilities with a sample of community adults. Therefore, the aim of this study was to examine the impact of a range of next-day responsibilities on demand for alcohol among a crowdsourced sample of community adults using a hypothetical alcohol purchase task (APT). Community adults (n = 261; 79% White; 60% identified as men; 39% identified as women; and 1% identified as nonbinary) with a mean age of 38.42 recruited from Amazon Mechanical Turk rank-ordered eight hypothetical next-day responsibilities across three categories (i.e., work, caregiving, and recreational). Participants first completed a standard APT with no explicit next-day responsibilities, followed by purchase tasks in the context of their two highest ranked responsibilities. All participants needed to pass several stages of attention and data quality checks to be included in the final sample. All observed demand indices (i.e., intensity, breakpoint, Omax, and Pmax) were significantly higher in the no responsibilities condition compared to both the first- and second-ranked responsibility condition (ps < .001); however, there was no significant difference in any demand index between the first- and second-ranked responsibility (p range .65-.91). These results extend prior work by demonstrating engagement with substance-free alternatives may reduce demand for alcohol among community adults. (PsycInfo Database Record (c) 2023 APA, all rights reserved).