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1.
Org Lett ; 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38975898

ABSTRACT

Ferrier photobromination enables direct synthetic access to valuable 5-C-bromosugars but has limitations that restrict its broader use. The reaction is typically conducted in CCl4 heated at reflux with irradiation by broad spectrum, energy-inefficient heat lamps. Herein, we demonstrate that the reaction proceeds rapidly and efficiently with PhCF3 as a safe and environmentally benign alternative to CCl4 at mild temperatures (≤40 °C) inside a compact photoreactor fitted with purple light-emitting diodes (LEDs).

2.
JAMA Dermatol ; 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38985481

ABSTRACT

This Patient Page describes the symptoms, diagnosis, and treatment of bed bugs.

3.
Res Sq ; 2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38946987

ABSTRACT

Fragile X syndrome (FXS) is a rare neurodevelopmental disorder caused by a CGG repeat expansion ≥ 200 repeats in 5' untranslated region of the FMR1 gene, leading to intellectual disability and cognitive difficulties, including in the domain of communication. A recent phase 2a clinical trial testing BPN14770, a phosphodiesterase 4D inhibitor, showed improved cognition in 30 adult males with FXS on drug relative to placebo. The initial study found significant improvements in clinical measures assessing cognition, language, and daily functioning in addition to marginal improvements in electroencephalography (EEG) results for the amplitude of the N1 event-related potential (ERP) component. EEG results suggest BPN14770 improved neural hyperexcitability in FXS. The current study investigated the relationship between BPN14770 pharmacokinetics (PK) and the amplitude of the N1 ERP component from the initial data. Consistent with the original group-level finding in period 1 of the study, participants who received BPN14770 in the period 1 showed a significant correlation between N1 amplitude and serum concentration of BPN14770. These findings strengthen the validity of the original result, indicating that BPN14770 improves cognitive performance by modulating neural hyperexcitability. This study represents the first report of significant correlation between a reliably abnormal EEG marker and serum concentration of a novel pharmaceutical in FXS.

4.
Sports Med Arthrosc Rev ; 32(2): 75-86, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38978201

ABSTRACT

Cartilage lesions of the knee are a challenging problem, especially for active individuals and athletes who desire a return to high-load activities. They occur both through chronic repetitive loading of the knee joint or through acute traumatic injury and represent a major cause of pain and time lost from sport. They can arise as isolated lesions or in association with concomitant knee pathology. Management of these defects ultimately requires a sound understanding of their pathophysiologic underpinnings to help guide treatment. Team physicians should maintain a high index of suspicion for underlying cartilage lesions in any patient presenting with a knee effusion, whether painful or not. A thorough workup should include a complete history and physical examination. MRI is the most sensitive and specific imaging modality to assess these lesions and can provide intricate detail not only of the structure and composition of cartilage, but also of the surrounding physiological environment in the joint. Treatment of these lesions consists of both conservative or supportive measures, as well as surgical interventions designed to restore or regenerate healthy cartilage. Because of the poor inherent capacity for healing associated with hyaline cartilage, the vast majority of symptomatic lesions will ultimately require surgery. Surgical treatment options range from simple arthroscopic debridement to large osteochondral reconstructions. Operative decision-making is based on numerous patient- and defect-related factors and requires open lines of communication between the athlete, the surgeon, and the rest of the treatment team. Ultimately, a positive outcome is based on the creation of a durable, resistant repair that allows the athlete to return to pain-free sporting activities.


Subject(s)
Athletic Injuries , Cartilage, Articular , Knee Injuries , Magnetic Resonance Imaging , Humans , Cartilage, Articular/injuries , Cartilage, Articular/surgery , Athletic Injuries/surgery , Athletic Injuries/therapy , Athletic Injuries/diagnosis , Knee Injuries/surgery , Arthroscopy/methods , Debridement , Athletes
5.
J Neurophysiol ; 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38985938

ABSTRACT

Bradykinesia is a term describing several manifestations of movement disruption caused by Parkinson's disease (PD), including movement slowing, amplitude reduction, and gradual decrease of speed and amplitude over multiple repetitions of the same movement. Deep brain stimulation (DBS) of the subthalamic nucleus (STN) improves bradykinesia in patients with PD. We examined the effect of DBS on specific components of bradykinesia when applied at two locations within the STN, using signal processing techniques to identify the time course of amplitude and frequency of repeated hand pronation-supination movements performed by participants with and without PD. Stimulation at either location increased movement amplitude, increased frequency, and decreased variability, though not to the range observed in the control group. Amplitude and frequency showed decrement within trials, which was similar in PD and control groups and did not change with DBS. Decrement across trials, by contrast, differed between PD and control groups, and was reduced by stimulation. We conclude that DBS improves specific aspects of movement that are disrupted by PD, whereas it does not affect short-term decrement that could reflect muscular fatigue.

7.
Brain Commun ; 6(4): fcae183, 2024.
Article in English | MEDLINE | ID: mdl-39021510

ABSTRACT

Predominant limbic degeneration has been associated with various underlying aetiologies and an older age, predominant impairment of episodic memory and slow clinical progression. However, the neurological syndrome associated with predominant limbic degeneration is not defined. This endeavour is critical to distinguish such a syndrome from those originating from neocortical degeneration, which may differ in underlying aetiology, disease course and therapeutic needs. We propose a set of clinical criteria for a limbic-predominant amnestic neurodegenerative syndrome that is highly associated with limbic-predominant age-related TDP-43 encephalopathy but also other pathologic entities. The criteria incorporate core, standard and advanced features, including older age at evaluation, mild clinical syndrome, disproportionate hippocampal atrophy, impaired semantic memory, limbic hypometabolism, absence of neocortical degeneration and low likelihood of neocortical tau, with degrees of certainty (highest, high, moderate and low). We operationalized this set of criteria using clinical, imaging and biomarker data to validate its associations with clinical and pathologic outcomes. We screened autopsied patients from Mayo Clinic and Alzheimer's Disease Neuroimaging Initiative cohorts and applied the criteria to those with an antemortem predominant amnestic syndrome (Mayo, n = 165; Alzheimer's Disease Neuroimaging Initiative, n = 53) and who had Alzheimer's disease neuropathological change, limbic-predominant age-related TDP-43 encephalopathy or both pathologies at autopsy. These neuropathology-defined groups accounted for 35, 37 and 4% of cases in the Mayo cohort, respectively, and 30, 22 and 9% of cases in the Alzheimer's Disease Neuroimaging Initiative cohort, respectively. The criteria effectively categorized these cases, with Alzheimer's disease having the lowest likelihoods, limbic-predominant age-related TDP-43 encephalopathy patients having the highest likelihoods and patients with both pathologies having intermediate likelihoods. A logistic regression using the criteria features as predictors of TDP-43 achieved a balanced accuracy of 74.6% in the Mayo cohort, and out-of-sample predictions in an external cohort achieved a balanced accuracy of 73.3%. Patients with high likelihoods had a milder and slower clinical course and more severe temporo-limbic degeneration compared to those with low likelihoods. Stratifying patients with both Alzheimer's disease neuropathological change and limbic-predominant age-related TDP-43 encephalopathy from the Mayo cohort according to their likelihoods revealed that those with higher likelihoods had more temporo-limbic degeneration and a slower rate of decline and those with lower likelihoods had more lateral temporo-parietal degeneration and a faster rate of decline. The implementation of criteria for a limbic-predominant amnestic neurodegenerative syndrome has implications to disambiguate the different aetiologies of progressive amnestic presentations in older age and guide diagnosis, prognosis, treatment and clinical trials.

8.
Neurooncol Adv ; 6(1): vdae094, 2024.
Article in English | MEDLINE | ID: mdl-38962752

ABSTRACT

Background: Nonauditory symptoms can be a prominent feature in patients with sporadic vestibular schwannoma (VS), but the cause of these symptoms is unknown. Inflammation is hypothesized to play a key role in the growth and symptomatic presentation of sporadic VS, and in this study, we investigated through translocator protein (TSPO) positron emission tomography (PET) whether inflammation occurred within the "normal appearing" brain of such patients and its association with tumor growth. Methods: Dynamic PET datasets from 15 patients with sporadic VS (8 static and 7 growing) who had been previously imaged using the TSPO tracer [11C](R)-PK11195 were included. Parametric images of [11C](R)-PK11195 binding potential (BPND) and the distribution volume ratio (DVR) were derived and compared across VS growth groups within both contralateral and ipsilateral gray (GM) and white matter (WM) regions. Voxel-wise cluster analysis was additionally performed to identify anatomical regions of increased [11C](R)-PK11195 binding. Results: Compared with static tumors, growing VS demonstrated significantly higher cortical (GM, 1.070 vs. 1.031, P = .03) and whole brain (GM & WM, 1.045 vs. 1.006, P = .03) [11C](R)-PK11195 DVR values. The voxel-wise analysis supported the region-based analysis and revealed clusters of high TSPO binding within the precentral, postcentral, and prefrontal cortex in patients with growing VS. Conclusions: We present the first in vivo evidence of increased TSPO expression and inflammation within the brains of patients with growing sporadic VS. These results provide a potential mechanistic insight into the development of nonauditory symptoms in these patients and highlight the need for further studies interrogating the role of neuroinflammation in driving VS symptomatology.

9.
Chest ; 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38964673

ABSTRACT

BACKGROUND: When comparing outcomes after sepsis, it is essential to account for patient case mix to make fair comparisons. We developed a model to assess risk-adjusted 30-day mortality in the Michigan Hospital Medicine Safety's sepsis initiative (HMS-Sepsis). QUESTION: Can HMS-Sepsis registry data adequately predict risk of 30-day mortality? Do performance assessments using adjusted vs unadjusted data differ? STUDY DESIGN AND METHODS: Retrospective cohort of community-onset sepsis hospitalizations in HMS-Sepsis registry (4/2022-9/2023), with split derivation (70%) and validation (30%) cohorts. We fit a risk-adjustment model (HMS-Sepsis mortality model) incorporating acute physiology, demographic, and baseline health data and assessed model performance using c-statistics, Brier's scores, and comparisons of predicted vs observed mortality by deciles of risk. We compared hospital performance (1st quintile, middle quintiles, 5th quintile) using observed versus adjusted mortality to understand the extent to which risk-adjustment impacted hospital performance assessment. RESULTS: Among 17,514 hospitalizations from 66 hospitals during the study period, 12,260 (70%) were used for model derivation and 5,254 (30%) for model validation. 30-day mortality for the total cohort was 19.4%. The final model included 13 physiologic variables, two physiologic interactions, and 16 demographic and chronic health variables. The most significant variables were age, metastatic solid tumor, temperature, altered mental status, and platelet count. The model c-statistic was 0.82 for the derivation cohort, 0.81 for the validation cohort, and ≥0.78 for all subgroups assessed. Overall calibration error was 0.0% and mean calibration error across deciles of risk was 1.5%. Standardized mortality ratios yielded different assessments than observed mortality for 33.9% of hospitals. CONCLUSIONS: The HMS-Sepsis mortality model had strong discrimination, adequate calibration, and reclassified one-third of hospitals to a different performance category from unadjusted mortality. Based on its strong performance, the HMS-Sepsis mortality model can aid in fair hospital benchmarking, assessment of temporal changes, and observational causal inference analysis.

10.
Mayo Clin Proc Digit Health ; 2(2): 192-206, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38983444

ABSTRACT

Mobile phone applications (MPAs) for substance use disorder (SUD) treatment are increasingly used by patients. Although pilot studies have shown promising results, multiple previous systematic reviews noted insufficient evidence for MPA use in SUD treatment-many of the previously published reviews evaluated different trials. Subsequently, we aimed to conduct an umbrella review of previously published reviews investigating the efficacy of MPAs for SUD treatment, excluding nicotine/tobacco because umbrella reviews have been done in this population and the nicotine/tobacco MPA approach often differs from SUD-focused MPAs. No previous reviews have included a statistical meta-analysis of clinical trials to quantify an estimated overall effect. Seven reviews met inclusion criteria, and 17 unique studies with available data were taken from those reviews for the meta-analysis. Overall, reviews reported a lack of evidence for recommending MPAs for SUD treatment. However, MPA-delivered recovery support services, cognitive behavioral therapy, and contingency management were identified across multiple reviews as having promising evidence for SUD treatment. Hedges g effect size for an MPA reduction in substance use-related outcomes relative to the control arm was insignificant (0.137; 95% CI, -0.056 to 0.330; P=.16). In subgroup analysis, contingency management (1.29; 95% CI, 1.088-1.482; τ 2=0; k=2) and cognitive behavioral therapy (0.02; 95% CI, 0.001-0.030; τ 2=0; k=2) were significant. Although contingency management's effect was large, both trials were small (samples of 40 and 30). This review includes an adapted framework for the American Psychiatric Association's MPA guidelines that clinicians can implement to review MPAs critically with patients.

11.
Open Forum Infect Dis ; 11(7): ofae364, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38994443

ABSTRACT

Background: Serious injection-related infections (SIRIs) in people who inject drugs often lead to prolonged hospitalizations or premature discharges. This may be in part due to provider reluctance to place peripherally inserted central catheters (PICCs) for outpatient parenteral antibiotic therapy in this population. Because internal medicine (IM) residents are often frontline providers in academic centers, understanding their perspectives on SIRI care is important to improve outcomes. Methods: We surveyed IM residents in a large urban multicenter hospital system about SIRI care with a novel case-based survey that elicited preferences, comfort, experience, and stigma. The survey was developed using expert review, cognitive interviewing, and pilot testing. Results are reported with descriptive statistics and linear regression. Results: Of 116 respondents (response rate 34%), most (73%) were uncomfortable discharging a patient with active substance use home with a PICC, but comfortable (87%) with discharge to postacute facilities. Many (∼40%) endorsed high levels of concern for PICC misuse or secondary line infections, but larger numbers cited concerns about home environment (50%) or loss to follow-up (68%). While overall rates were low, higher stigma was associated with more concerns around PICC use (r = -0.3, P = .002). A majority (58%) believed hospital policies against PICC use in SIRI may act as a barrier to discharge, and 74% felt initiation of medications for opioid use disorder (MOUD) would increase their comfort discharging with a PICC. Conclusions: Most IM residents endorsed high levels of concern about PICC use for SIRI, related to patient outcomes and perceived institutional barriers, but identified MOUD as a mitigating factor.

12.
medRxiv ; 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38978656

ABSTRACT

Epigenetic processes, such as DNA methylation, show potential as biological markers and mechanisms underlying gene-environment interplay in the prediction of mental health and other brain-based phenotypes. However, little is known about how peripheral epigenetic patterns relate to individual differences in the brain itself. An increasingly popular approach to address this is by combining epigenetic and neuroimaging data; yet, research in this area is almost entirely comprised of cross-sectional studies in adults. To bridge this gap, we established the Methylation, Imaging and NeuroDevelopment (MIND) Consortium, which aims to bring a developmental focus to the emerging field of Neuroimaging Epigenetics by (i) promoting collaborative, adequately powered developmental research via multi-cohort analyses; (ii) increasing scientific rigor through the establishment of shared pipelines and open science practices; and (iii) advancing our understanding of DNA methylation-brain dynamics at different developmental periods (from birth to emerging adulthood), by leveraging data from prospective, longitudinal pediatric studies. MIND currently integrates 15 cohorts worldwide, comprising (repeated) measures of DNA methylation in peripheral tissues (blood, buccal cells, and saliva) and neuroimaging by magnetic resonance imaging across up to five time points over a period of up to 21 years (Npooled DNAm = 11,299; Npooled neuroimaging = 10,133; Npooled combined = 4,914). By triangulating associations across multiple developmental time points and study types, we hope to generate new insights into the dynamic relationships between peripheral DNA methylation and the brain, and how these ultimately relate to neurodevelopmental and psychiatric phenotypes.

13.
J Rural Health ; 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38953158

ABSTRACT

PURPOSE: To investigate the enduring disparities in adverse COVID-19 events between urban and rural communities in the United States, focusing on the effects of SARS-CoV-2 vaccination and therapeutic advances on patient outcomes. METHODS: Using National COVID Cohort Collaborative (N3C) data from 2021 to 2023, this retrospective cohort study examined COVID-19 hospitalization, inpatient death, and other adverse events. Populations were categorized into urban, urban-adjacent rural (UAR), and nonurban-adjacent rural (NAR). Adjustments included demographics, variant-dominant waves, comorbidities, region, and SARS-CoV-2 treatment and vaccination. Statistical methods included Kaplan-Meier survival estimates, multivariable logistic, and Cox regression. FINDINGS: The study included 3,018,646 patients, with rural residents constituting 506,204. These rural dwellers were older, had more comorbidities, and were less vaccinated than their urban counterparts. Adjusted analyses revealed higher hospitalization odds in UAR and NAR (aOR 1.07 [1.05-1.08] and 1.06 [1.03-1.08]), greater inpatient death hazard (aHR 1.30 [1.26-1.35] UAR and 1.37 [1.30-1.45] NAR), and greater risk of other adverse events compared to urban dwellers. Delta increased, while Omicron decreased, inpatient adverse events relative to pre-Delta, with rural disparities persisting throughout. Treatment effectiveness and vaccination were similarly protective across all cohorts, but dexamethasone post-ventilation was effective only in urban areas. Nirmatrelvir/ritonavir and molnupiravir better protected rural residents against hospitalization. CONCLUSIONS: Despite advancements in treatment and vaccinations, disparities in adverse COVID-19 outcomes persist between urban and rural communities. The effectiveness of some therapeutic agents appears to vary based on rurality, suggesting a nuanced relationship between treatment and geographic location while highlighting the need for targeted rural health care strategies.

14.
Drug Test Anal ; 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38978169

ABSTRACT

Blood phosphatidylethanol (PEth), a metabolite of ethanol, is emerging as a direct biomarker of choice for characterizing ethanol consumption in clinical, research, and forensic contexts. An accumulating body of evidence, and a recent international consensus conference, supports a cutoff of 20 µg/L of PEth (16:0/18:1) to distinguish abstinence from beverage ethanol consumption. There is a dearth of research, however, on whether exposures to nonbeverage ethanol sources are sufficient to produce PEth concentrations that exceed this cutoff. To explore this possibility, we recruited 30 participants, who indicated past-90-day abstinence from beverage alcohol, to characterize their past-30-day nonbeverage ethanol exposures (including source, frequency, and intensity of exposures) and to undergo PEth testing. Two of the 30 participants (6.7%) produced PEth concentrations ≥20 µg/L. One of these participants (PEth = 26 µg/L) reported multiple ethanol exposure sources, including near-daily intensive exposures to ethanol vapor. The other participant (PEth = 49 µg/L) reported only once-daily use of an ethanol-containing mouthwash; the veracity of his abstinence claim is refuted. The results of this study support a rebuttable presumption that PEth ≥20 µg/L is indicative of beverage ethanol consumption. They suggest, however, that intensive, incidental alcohol exposures have the potential, under unusual circumstances, to result in PEth concentrations that modestly exceed this threshold.

15.
Diabetes Obes Metab ; 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38978184

ABSTRACT

AIMS: To examine the impact of impaired glycaemic regulation (IGR) and exercise training on hepatic lipid composition in men with metabolic dysfunction-associated steatotic liver disease (MASLD). MATERIALS AND METHODS: In Part A (cross-sectional design), 40 men with MASLD (liver proton density fat fraction [PDFF] ≥5.56%) were recruited to one of two groups: (1) normal glycaemic regulation (NGR) group (glycated haemoglobin [HbA1c] < 42 mmol∙mol-1 [<6.0%]; n = 14) or (2) IGR group (HbA1c ≥ 42 mmol∙mol-1 [≥6.0%]; n = 26). In Part B (randomized controlled trial design), participants in the IGR group were randomized to one of two 6-week interventions: (1) exercise training (EX; 70%-75% maximum heart rate; four sessions/week; n = 13) or (2) non-exercise control (CON; n = 13). Saturated (SI; primary outcome), unsaturated (UI) and polyunsaturated (PUI) hepatic lipid indices were determined using proton magnetic resonance spectroscopy. Additional secondary outcomes included liver PDFF, HbA1c, fasting plasma glucose (FPG), homeostatic model assessment of insulin resistance (HOMA-IR), peak oxygen uptake (VO2 peak), and plasma cytokeratin-18 (CK18) M65, among others. RESULTS: In Part A, hepatic SI was higher and hepatic UI was lower in the IGR versus the NGR group (p = 0.038), and this hepatic lipid profile was associated with higher HbA1c levels, FPG levels, HOMA-IR and plasma CK18 M65 levels (rs ≥0.320). In Part B, hepatic lipid composition and liver PDFF were unchanged after EX versus CON (p ≥ 0.257), while FPG was reduced and VO2 peak was increased (p ≤ 0.030). ΔVO2 peak was inversely associated with Δhepatic SI (r = -0.433) and positively associated with Δhepatic UI and Δhepatic PUI (r ≥ 0.433). CONCLUSIONS: Impaired glycaemic regulation in MASLD is characterized by greater hepatic lipid saturation; however, this composition is not altered by 6 weeks of moderate-intensity exercise training.

16.
Article in English | MEDLINE | ID: mdl-38991134

ABSTRACT

Native mass spectrometry (MS) is a powerful analytical technique to directly probe noncovalent protein-protein and protein-ligand interactions. However, not every MS platform can preserve proteins in their native conformation due to high energy deposition from the utilized ionization source. Most small molecules approved as drugs and in development interact with their targets through noncovalent interactions. Therefore, rapid methods to analyze noncovalent protein-ligand interactions are necessary for the early stages of the drug discovery pipeline. Herein, we describe a method for analyzing noncovalent protein-ligand complexes by IR-MALDESI-MS with analysis times of ∼13 s per sample. Carbonic anhydrase and the kinase domain of Bruton's tyrosine kinase are paired with known noncovalent binders to evaluate the effectiveness of native MS by IR-MALDESI.

17.
Toxicon ; : 107856, 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38992508

ABSTRACT

For more than a century, concerns about the medical significance of Montpellier snakes, Malpolon spp. (Psammophiidae, Psammophiinae) have been expressed by herpetologists and toxinologists. Although some of the opinions have suggested that the most familiar species, the Western Montpellier snake, Malpolon monspessulanus, poses a significant medical risk, only a few detailed, formally documented reports have been published that describe effects in humans. Two reports support a rare risk of systemic envenoming (cranial nerve palsies) after prolonged bites by M. monspessulanus. Relevantly, there has been only one previous report describing a bite by the Eastern Montpellier snake, Malpolon insignitus. Reported here are the effects of a bite inflicted by a 1.1-meter female Malpolon insignitus fuscus in Alborz Province, Iran. The 40-yr-old male victim was handling the snake while preparing to photograph it when he was bitten on the right wrist. The snake remained attached for approximately 40-seconds during which it repeatedly advanced its jaws. The bite caused moderate local envenoming that featured moderate but reportedly notably uncomfortable sharp pain, moderate edema, erythema and pruritis; wound site bleeding was transient and proportional. Full resolution required 5-days; there were no sequelae. The clinical evolution included signs/symptoms consistent with Type I hypersensitivity and subtype Type IV hypersensitivity. Detailed reports of medically significant bites by Malpolon spp. are briefly reviewed and the evidence for medical significance of the genus is evaluated. Management of envenoming by Malpolon spp. is supportive only; almost all victims with qualified medical review have developed only local envenoming that is often mild-moderate. Notably rare systemic effects, e.g., neurotoxicity so far limited to non-progressive cranial nerve palsies, should prompt airway protection, ICU admission, and consultation as indicated. Future study of Malpolon venoms and formal documentation of their bites should increase the evidence quality for the medical risk profile of the genus.

18.
Commun Biol ; 7(1): 845, 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38987622

ABSTRACT

Adult Neural Stem Cells (aNSCs) in the ventricular-subventricular zone (V-SVZ) are largely quiescent. Here, we characterize the mechanism underlying the functional role of a cell-signalling inhibitory protein, LRIG1, in the control of aNSCs proliferation. Using Lrig1 knockout models, we show that Lrig1 ablation results in increased aNSCs proliferation with no change in neuronal progeny and that this hyperproliferation likely does not result solely from activation of the epidermal growth factor receptor (EGFR). Loss of LRIG1, however, also leads to impaired activation of transforming growth factor beta (TGFß) and bone morphogenic protein (BMP) signalling. Biochemically, we show that LRIG1 binds TGFß/BMP receptors and the TGFß1 ligand. Finally, we show that the consequences of these interactions are to facilitate SMAD phosphorylation. Collectively, these data suggest that unlike in embryonic NSCs where EGFR may be the primary mechanism of action, in aNSCs, LRIG1 and TGFß pathways function together to fulfill their inhibitory roles.


Subject(s)
Bone Morphogenetic Proteins , Cell Proliferation , Membrane Glycoproteins , Neural Stem Cells , Signal Transduction , Transforming Growth Factor beta , Animals , Neural Stem Cells/metabolism , Neural Stem Cells/cytology , Transforming Growth Factor beta/metabolism , Membrane Glycoproteins/metabolism , Membrane Glycoproteins/genetics , Mice , Bone Morphogenetic Proteins/metabolism , Mice, Knockout , Adult Stem Cells/metabolism , ErbB Receptors/metabolism , ErbB Receptors/genetics , Nerve Tissue Proteins
19.
Pediatr Pulmonol ; 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38958238

ABSTRACT

OBJECTIVES: To quantify the association of ambient air pollution (particulate matter, PM2.5) exposure with medically attended acute respiratory illness among infants with bronchopulmonary dysplasia (BPD). STUDY DESIGN: Single center, retrospective cohort study of preterm infants with BPD in Metropolitan Philadelphia. Multivariable logistic regression quantified associations of annual mean PM2.5 exposure (per µg/m3) at the census block group level with medically attended acute respiratory illness, defined as emergency department (ED) visits or hospital readmissions within a year after first hospital discharge adjusting for age at neonatal intensive care unit (NICU) discharge, year, sex, race, insurance, BPD severity, and census tract deprivation. As a secondary analysis, we examined whether BPD severity modified the associations. RESULTS: Of the 378 infants included in the analysis, 189 were non-Hispanic Black and 235 were publicly insured. Census block PM2.5 level was not significantly associated with medically attended acute respiratory illnesses, ED visits, or hospital readmissions in the full study cohort. We observed significant effect modification by BPD grade; each 1 µg/m3 higher annual PM2.5 exposure was medically attended acute respiratory illness (adjusted odds ratio [aOR] 1.65, 95% CI: 1.06-2.63) among infants with Grade 1 BPD but not among infants with grade 3 BPD (aOR 0.83, 95% CI: 0.47-1.48) (interaction p = .024). CONCLUSIONS: Cumulative PM2.5 exposure in the year after NICU discharge was not significantly associated with medically attended acute respiratory illness among infants with BPD. However, infants with Grade 1 BPD had significantly higher odds with higher exposures. If replicated, these findings could inform anticipatory guidance for families of these infants to avoid outdoor activities during high pollution days after NICU discharge.

20.
Nucleic Acids Res ; 2024 Jul 17.
Article in English | MEDLINE | ID: mdl-39016170

ABSTRACT

The endonuclease activity of Pms1 directs mismatch repair by generating a nick in the newly replicated DNA strand. Inactivating Pms2, the human homologue of yeast Pms1, increases the chances of colorectal and uterine cancers. Here we use whole genome sequencing to show that loss of this endonuclease activity, via the pms1-DE variant, results in strong mutator effects throughout the Saccharomyces cerevisiae genome. Mutation rates are strongly increased for mutations resulting from all types of single-base substitutions and for a wide variety of single- and multi-base indel mutations. Rates for these events are further increased in strains combining pms1-DE with mutator variants of each of the three major leading and lagging strand replicases. In all cases, mutation rates, spectra, biases, and context preferences are statistically indistinguishable from strains with equivalent polymerases but lacking initial mismatch recognition due to deletion of MSH2. This implies that, across the nuclear genome, strand discrimination via the Pms1 endonuclease is as important for MMR as is initial mismatch recognition by Msh2 heterodimers.

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