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1.
medRxiv ; 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38978643

ABSTRACT

Frontotemporal lobar degeneration with neuronal inclusions of the TAR DNA-binding protein 43 (FTLD-TDP) is a fatal neurodegenerative disorder with only a limited number of risk loci identified. We report our comprehensive genome-wide association study as part of the International FTLD-TDP Whole-Genome Sequencing Consortium, including 985 cases and 3,153 controls, and meta-analysis with the Dementia-seq cohort, compiled from 26 institutions/brain banks in the United States, Europe and Australia. We confirm UNC13A as the strongest overall FTLD-TDP risk factor and identify TNIP1 as a novel FTLD-TDP risk factor. In subgroup analyses, we further identify for the first time genome-wide significant loci specific to each of the three main FTLD-TDP pathological subtypes (A, B and C), as well as enrichment of risk loci in distinct tissues, brain regions, and neuronal subtypes, suggesting distinct disease aetiologies in each of the subtypes. Rare variant analysis confirmed TBK1 and identified VIPR1 , RBPJL , and L3MBTL1 as novel subtype specific FTLD-TDP risk genes, further highlighting the role of innate and adaptive immunity and notch signalling pathway in FTLD-TDP, with potential diagnostic and novel therapeutic implications.

2.
bioRxiv ; 2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38948776

ABSTRACT

Cachexia is a wasting syndrome comprised of adipose, muscle, and weight loss observed in cancer patients. Tumor loss-of-function mutations in STK11/LKB1 , a regulator of the energy sensor AMP-activated protein kinase, induce cancer cachexia (CC) in preclinical models and are associated with cancer-related weight loss in NSCLC patients. Here we characterized the relevance of the NSCLC-associated cachexia factor growth differentiation factor 15 (GDF15) in several patient-derived and genetically engineered STK11/LKB1 -mutant NSCLC cachexia lines. Both tumor mRNA expression and serum concentrations of tumor-derived GDF15 were significantly elevated in multiple mice transplanted with patient-derived STK11/LKB1 -mutated NSCLC lines. GDF15 neutralizing antibody administered to mice transplanted with patient- or mouse-derived STK11/LKB1 -mutated NSCLC lines suppressed cachexia-associated adipose loss, muscle atrophy, and changes in body weight. The silencing of GDF15 in multiple human NSCLC lines was also sufficient to eliminate in vivo circulating GDF15 levels and abrogate cachexia induction, suggesting that tumor and not host tissues represent a key source of GDF15 production in these cancer models. Finally, reconstitution of wild-type STK11/LKB1 in a human STK11/LKB1 loss-of-function NSCLC line that normally induces cachexia in vivo correlated with the absence of tumor-secreted GDF15 and rescue from the cachexia phenotype. The current data provide evidence for tumor-secreted GDF15 as a conduit and a therapeutic target through which NSCLCs with STK11/LKB1 loss-of-function mutations promote cachexia-associated wasting.

4.
Ann Surg Oncol ; 2024 Jun 02.
Article in English | MEDLINE | ID: mdl-38825628

ABSTRACT

BACKGROUND: The 8th edition American Joint Committee on Cancer staging system combined anatomic stage (AS) with receptor status and grade to create prognostic stage (PS). PS has been validated in single-institution and cancer registry studies; however, missing human epidermal growth factor receptor 2 (HER2) status and variable treatment and follow-up create limitations. OBJECTIVE: Our objective was to compare the relative prognostic ability of PS versus AS to predict survival using breast cancer clinical trial data. METHODS: Women with non-metastatic breast cancer enrolled in six Alliance for Clinical Trials in Oncology trials were included (enrollment years 1997-2010). AS and PS were constructed using pathological tumor size, nodal status, estrogen receptor (ER), progesterone receptor (PR), HER2 status, and grade. Unadjusted Cox proportional hazard models were estimated to predict overall survival within 5 years, with AS and PS as predictor variables. The relative predictive power of staging models was assessed by comparing Harrell concordance indices (C-indices). Kaplan-Meier-based mortality estimates were compared by stage. RESULTS: Overall, 6924 women were included (median age 53 years); 45.2% were diagnosed with ER+/PR+/HER2- tumors, 26.2% with HER2+ tumors, and 17.1% with ER-/PR-/HER2- tumors. Median follow-up time was 5 years (interquartile range 2.95-5.00). PS significantly improved predictive performance (C-index 0.721) for overall survival compared with AS (0.700) (p = 0.020). Kaplan-Meier hazard estimates suggested PS did not distinguish mortality risk between patients with IIB and IIIA or IB and IIA disease. CONCLUSIONS: PS has significantly improved predictive performance for OS compared with AS. As systemic therapies evolve, it will be important to re-evaluate the prognostic staging system, particularly for patients with intermediate-stage cancers. CLINICALTRIALS: gov Identifier: NCT02171078.

5.
Nat Commun ; 15(1): 4571, 2024 May 29.
Article in English | MEDLINE | ID: mdl-38811551

ABSTRACT

Evolution results from the interaction of stochastic and deterministic processes that create a web of historical contingency, shaping gene content and organismal function. To understand the scope of this interaction, we examine the relative contributions of stochasticity, determinism, and contingency in shaping gene inactivation in 34 lineages of endosymbiotic bacteria, Sodalis, found in parasitic lice, Columbicola, that are independently undergoing genome degeneration. Here we show that the process of genome degeneration in this system is largely deterministic: genes involved in amino acid biosynthesis are lost while those involved in providing B-vitamins to the host are retained. In contrast, many genes encoding redundant functions, including components of the respiratory chain and DNA repair pathways, are subject to stochastic loss, yielding historical contingencies that constrain subsequent losses. Thus, while selection results in functional convergence between symbiont lineages, stochastic mutations initiate distinct evolutionary trajectories, generating diverse gene inventories that lack the functional redundancy typically found in free-living relatives.


Subject(s)
Evolution, Molecular , Genome, Bacterial , Phylogeny , Stochastic Processes , Symbiosis , Symbiosis/genetics , Genome, Bacterial/genetics , Animals , Enterobacteriaceae/genetics , Enterobacteriaceae/metabolism , Mutation
6.
Ann Surg Oncol ; 31(7): 4487-4497, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38557909

ABSTRACT

BACKGROUND: Radioactive tracer injections for breast cancer sentinel lymph node mapping can be painful. In this randomized trial, we compared four approaches to topical pain control for radiotracer injections. METHODS: Breast cancer patients were randomized (9 April 2021-8 May 2022) to receive the institutional standard of ice prior to injection (n = 44), or one of three treatments: ice plus a vibrating distraction device (Buzzy®; n = 39), 4% lidocaine patch (n = 44), or 4% lidocaine patch plus ice plus Buzzy® (n = 40). Patients completed the Wong-Baker FACES® pain score (primary outcome) and a satisfaction with pain control received scale (secondary). Nuclear medicine technologists (n = 8) rated perceived pain control and ease of administration for each patient. At study conclusion, technologists rank-ordered treatments. Data were analyzed as intention-to-treat. Wilcoxon rank-sum tests were used to compare pain scores of control versus pooled treatment arms (primary) and then control to each treatment arm individually (secondary). RESULTS: There were no differences in pain scores between the control and treatment groups, both pooled and individually. Eighty-five percent of patients were 'satisfied/very satisfied' with treatment received, with no differences between groups. No differences in providers' perceptions of pain were observed, although providers perceived treatments involving Buzzy© more difficult to administer (p < 0.001). Providers rated lidocaine patch as the easiest, with ice being second. CONCLUSION: In this randomized trial, no differences in patient-reported pain or satisfaction with treatment was observed between ice and other topical treatments. Providers found treatments using Buzzy® more difficult to administer. Given patient satisfaction and ease of administration, ice is a reasonable standard.


Subject(s)
Anesthetics, Local , Breast Neoplasms , Lidocaine , Pain Management , Humans , Female , Breast Neoplasms/pathology , Breast Neoplasms/drug therapy , Middle Aged , Pain Management/methods , Lidocaine/administration & dosage , Anesthetics, Local/administration & dosage , Sentinel Lymph Node/pathology , Radiopharmaceuticals/administration & dosage , Aged , Sentinel Lymph Node Biopsy/methods , Adult , Follow-Up Studies , Prognosis , Ice , Pain Measurement , Pain/etiology , Pain/prevention & control , Pain/drug therapy , Administration, Topical
8.
Mol Biol Evol ; 41(4)2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38513084

ABSTRACT

Insects have repeatedly forged symbioses with heritable microbes, gaining novel traits. For the microbe, the transition to symbioses can lead to the degeneration of the symbiont's genome through transmission bottlenecks, isolation, and the loss of DNA repair enzymes. However, some insect-microbial symbioses have persisted for millions of years, suggesting that natural selection slows genetic drift and maintains functional consistency between symbiont populations. By sampling in multiple countries, we examine genomic diversity within a symbiont species, a heritable symbiotic bacterium found only in human head lice. We find that human head louse symbionts contain genetic diversity that appears to have arisen contemporaneously with the appearance of anatomically modern humans within Africa and/or during the colonization of Eurasia by humans. We predict that the observed genetic diversity underlies functional differences in extant symbiont lineages, through the inactivation of genes involved in symbiont membrane construction. Furthermore, we find evidence of additional gene losses prior to the appearance of modern humans, also impacting the symbiont membrane. From this, we conclude that symbiont genome degeneration is proceeding, via gene inactivation and subsequent loss, in human head louse symbionts, while genomic diversity is maintained. Collectively, our results provide a look into the genomic diversity within a single symbiont species and highlight the shared evolutionary history of humans, lice, and bacteria.


Subject(s)
Hominidae , Pediculus , Animals , Humans , Pediculus/genetics , Phylogeny , Genome, Bacterial , Evolution, Molecular , Bacteria/genetics , Genomics , Hominidae/genetics , Insecta/genetics , Symbiosis/genetics
9.
Front Nutr ; 11: 1340735, 2024.
Article in English | MEDLINE | ID: mdl-38425486

ABSTRACT

Introduction: Obesity is prevalent with the adult population in the United States. Energy-dense diets and erratic eating behavior contribute to obesity. Time-restricted eating is a dietary strategy in humans that has been advanced to reduce the propensity for obesity. We hypothesized that time-restricted feeding (TRF) would improve metabolic flexibility and normalize metabolic function in adult mice with established excess adiposity. Methods: Male C57BL/6NHsd mice were initially fed a high-fat diet (HFD) for 12 weeks to establish excess body adiposity, while control mice were fed a normal diet. Then, the HFD-fed mice were assigned to two groups, either ad libitum HFD or TRF of the HFD in the dark phase (12 h) for another 12 weeks. Results and discussion: Energy intake and body fat mass were similar in TRF and HFD-fed mice. TRF restored rhythmic oscillations of respiratory exchange ratio (RER), which had been flattened by the HFD, with greater RER amplitude in the dark phase. Insulin sensitivity was improved and plasma cholesterol and hepatic triacylglycerol were decreased by TRF. When compared to HFD, TRF decreased transcription of circadian genes Per1 and Per2 and genes encoding lipid metabolism (Acaca, Fads1, Fads2, Fasn, Scd1, and Srebf1) in liver. Metabolomic analysis showed that TRF created a profile that was distinct from those of mice fed the control diet or HFD, particularly in altered amino acid profiles. These included aminoacyl-tRNA-biosynthesis, glutathione metabolism, and phenylalanine, tyrosine, and tryptophan biosynthesis pathways. In conclusion, TRF improved metabolic function in adult mice with excess adiposity. This improvement was not through a reduction in body fat mass but through the restoration of metabolic flexibility.

10.
Cancer Res ; 84(10): 1719-1732, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38451249

ABSTRACT

Longitudinal monitoring of patients with advanced cancers is crucial to evaluate both disease burden and treatment response. Current liquid biopsy approaches mostly rely on the detection of DNA-based biomarkers. However, plasma RNA analysis can unleash tremendous opportunities for tumor state interrogation and molecular subtyping. Through the application of deep learning algorithms to the deconvolved transcriptomes of RNA within plasma extracellular vesicles (evRNA), we successfully predicted consensus molecular subtypes in patients with metastatic colorectal cancer. Analysis of plasma evRNA also enabled monitoring of changes in transcriptomic subtype under treatment selection pressure and identification of molecular pathways associated with recurrence. This approach also revealed expressed gene fusions and neoepitopes from evRNA. These results demonstrate the feasibility of using transcriptomic-based liquid biopsy platforms for precision oncology approaches, spanning from the longitudinal monitoring of tumor subtype changes to the identification of expressed fusions and neoantigens as cancer-specific therapeutic targets, sans the need for tissue-based sampling. SIGNIFICANCE: The development of an approach to interrogate molecular subtypes, cancer-associated pathways, and differentially expressed genes through RNA sequencing of plasma extracellular vesicles lays the foundation for liquid biopsy-based longitudinal monitoring of patient tumor transcriptomes.


Subject(s)
Biomarkers, Tumor , Extracellular Vesicles , Gene Expression Profiling , Transcriptome , Humans , Extracellular Vesicles/genetics , Extracellular Vesicles/metabolism , Gene Expression Profiling/methods , Biomarkers, Tumor/genetics , Biomarkers, Tumor/blood , Liquid Biopsy/methods , Colorectal Neoplasms/genetics , Colorectal Neoplasms/blood , Colorectal Neoplasms/pathology , Gene Expression Regulation, Neoplastic , Neoplasms/genetics , Neoplasms/blood , Neoplasms/pathology
11.
J Clin Rheumatol ; 2024 Mar 05.
Article in English | MEDLINE | ID: mdl-38446494

ABSTRACT

BACKGROUND/OBJECTIVE: To address high blood pressure (BP) in rheumatology patients, we previously implemented BP Connect, a brief staff-driven protocol to address high BP. Although timely follow-up and hypertension rates improved for patients with in-system primary care (PC), many receive PC and rheumatology care in separate health systems. In this cohort study, we compared rates of timely PC follow-up for high BP across-system health maintenance organizations (HMOs) before and after BP Connect implementation. METHODS: All adult patients with high rheumatology clinic BP and PC in that HMO were eligible. BP Connect's protocol engaged the staff in remeasuring high BP (≥140/90 mm Hg), advising cardiovascular disease risk, and connecting timely PC follow-up, which for patients with PC across system includes written follow-up instructions. After an eligible rheumatology visit, the next HMO PC visit with BP was used to determine rates and odds of timely follow-up before and after using multivariable logistic regression. RESULTS: Across 1327 rheumatology visits with high BP and across-system PC (2013-2019), 951 occurred after 2015 BP Connect implementation; 400 had confirmed high BP. Primary care follow-up rose from 20.5% to 23.5%. The odds of timely PC BP follow-up insignificantly changed (odds ratio, 1.19; confidence interval, 0.85-1.68). For visits with Black patients, the odds of timely follow-up did significantly increase (1.95; confidence interval, 1.02-3.79). CONCLUSIONS: Timely follow-up for Black patients did improve, highlighting protocol interventions for more equitable health care. In contrast to our prior in-system study, BP Connect did not significantly improve follow-up with an across-system PC, indicating a need for direct scheduling. Future directions include piloting direct across-system scheduling.

12.
Acta Neuropathol ; 147(1): 46, 2024 02 27.
Article in English | MEDLINE | ID: mdl-38411740

ABSTRACT

At least five enzymes including three E3 ubiquitin ligases are dedicated to glycogen's spherical structure. Absence of any reverts glycogen to a structure resembling amylopectin of the plant kingdom. This amylopectinosis (polyglucosan body formation) causes fatal neurological diseases including adult polyglucosan body disease (APBD) due to glycogen branching enzyme deficiency, Lafora disease (LD) due to deficiencies of the laforin glycogen phosphatase or the malin E3 ubiquitin ligase and type 1 polyglucosan body myopathy (PGBM1) due to RBCK1 E3 ubiquitin ligase deficiency. Little is known about these enzymes' functions in glycogen structuring. Toward understanding these functions, we undertake a comparative murine study of the amylopectinoses of APBD, LD and PGBM1. We discover that in skeletal muscle, polyglucosan bodies form as two main types, small and multitudinous ('pebbles') or giant and single ('boulders'), and that this is primarily determined by the myofiber types in which they form, 'pebbles' in glycolytic and 'boulders' in oxidative fibers. This pattern recapitulates what is known in the brain in LD, innumerable dust-like in astrocytes and single giant sized in neurons. We also show that oxidative myofibers are relatively protected against amylopectinosis, in part through highly increased glycogen branching enzyme expression. We present evidence of polyglucosan body size-dependent cell necrosis. We show that sex influences amylopectinosis in genotype, brain region and myofiber-type-specific fashion. RBCK1 is a component of the linear ubiquitin chain assembly complex (LUBAC), the only known cellular machinery for head-to-tail linear ubiquitination critical to numerous cellular pathways. We show that the amylopectinosis of RBCK1 deficiency is not due to loss of linear ubiquitination, and that another function of RBCK1 or LUBAC must exist and operate in the shaping of glycogen. This work opens multiple new avenues toward understanding the structural determinants of the mammalian carbohydrate reservoir critical to neurologic and neuromuscular function and disease.


Subject(s)
Glycogen Storage Disease Type IV , Glycogen Storage Disease , Nervous System Diseases , Animals , Mice , Glycogen , Ubiquitin-Protein Ligases , Ubiquitins , Mammals
13.
PEC Innov ; 4: 100260, 2024 Dec.
Article in English | MEDLINE | ID: mdl-38347862

ABSTRACT

Objective: To describe the outcomes of training nephrology clinicians and clinical research participants, to use the Best Case/Worst Case Communication intervention, for discussions about dialysis initiation for patients with life-limiting illness, during a randomized clinical trial to ensure competency, fidelity to the intervention, and adherence to study protocols and the intervention throughout the trial. Methods: We enrolled 68 nephrologists at ten study sites and randomized them to receive training or wait-list control. We collected copies of completed graphic aids (component of the intervention), used with study-enrolled patients, to measure fidelity and adherence. Results: We trained 34 of 36 nephrologists to competence and 27 completed the entire program. We received 60 graphic aids for study-enrolled patients for a 73% return rate in the intervention arm. The intervention fidelity score for the graphic aid reflected completion of all elements throughout the study. Conclusion: We successfully taught the Best Case/Worst Case Communication intervention to clinicians as research participants within a randomized clinical trial. Innovation: Decisions about dialysis are an opportunity to discuss prognosis and uncertainty in relation to consideration of prolonged life supporting therapy. Our study reveals a strategy to evaluate adherence to a communication intervention in real time during a clinical study.

14.
Ann Surg ; 2024 Feb 08.
Article in English | MEDLINE | ID: mdl-38328985

ABSTRACT

OBJECTIVE: The objective of this study was to understand professional norms regarding the value of surgery. SUMMARY BACKGROUND DATA: Agreed-upon professional norms may improve surgical decision making by contextualizing the nature of surgical treatment for patients. However, the extent to which these norms exist among surgeons practicing in the US is not known. METHODS: We administered a survey with 30 exemplar cases asking surgeons to use their best judgement to place each case on a scale ranging from "Definitely would do this surgery" to "Definitely would not do this surgery." We then asked surgeons to repeat their assessments after providing responses from the first survey. We interviewed respondents to characterize their rationale. RESULTS: We received 580 responses, a response rate of 28.5%. For 19 of 30 cases there was consensus (≥60% agreement) about the value of surgery (range 63% - 99%). There was little within-case variation when the mode was for surgery and more variation when the mode was against surgery or equipoise. Exposure to peer response increased the number of cases with consensus. Women were more likely to endorse a non-operative approach when treatment had high mortality. Specialists were less likely to operate for salvage procedures. Surgeons noted their clinical practice was to withhold judgment and let patients decide despite their assessment. CONCLUSIONS: Professional judgment about the value of surgery exists along a continuum. While there is less variation in judgment for cases that are highly beneficial, consensus can be improved by exposure to the assessments of peers.

15.
Pulmonology ; 2024 Feb 24.
Article in English | MEDLINE | ID: mdl-38403573

ABSTRACT

INTRODUCTION AND OBJECTIVES: The human congenital central hypoventilation syndrome (CCHS) is caused by mutations in the PHOX2B (paired-like homeobox 2B) gene. Genetically engineered PHOX2B rodents exhibit defective development of the brainstem retrotrapezoid nucleus (RTN), a carbon dioxide sensitive structure that critically controls expiratory muscle recruitment. This has been linked to a blunted exercise ventilatory response. Whether this can be extrapolated to human CCHS is unknown and represents the objective of this study. MATERIALS AND METHODS: Thirteen adult CCHS patients and 13 healthy participants performed an incremental symptom-limited cycle cardiopulmonary exercise test. Responses were analyzed using guideline approaches (ventilation V'E, tidal volume VT, breathing frequency, oxygen consumption, carbon dioxide production) complemented by a breathing pattern analysis (i.e. expiratory and inspiratory reserve volume, ERV and IRV). RESULTS: A ventilatory response occurred in both study groups, as follows: V'E and VT increased in CCHS patients until 40 W and then decreased, which was not observed in the healthy participants (p<0.001). In the latter, exercise-related ERV and IRV decreases attested to concomitant expiratory and inspiratory recruitment. In the CCHS patients, inspiratory recruitment occurred but there was no evidence of expiratory recruitment (absence of any ERV decrease, p<0.001). CONCLUSIONS: Assuming a similar organization of respiratory rhythmogenesis in humans and rodents, the lack of exercise-related expiratory recruitment observed in our CCHS patients is compatible with a PHOX2B-related defect of a neural structure that would be analogous to the rodents' RTN. Provided corroboration, ERV recruitment could serve as a physiological outcome in studies aiming at correcting breathing control in CCHS.

16.
Elife ; 122024 Jan 26.
Article in English | MEDLINE | ID: mdl-38277211

ABSTRACT

Adolescent idiopathic scoliosis (AIS) is a common and progressive spinal deformity in children that exhibits striking sexual dimorphism, with girls at more than fivefold greater risk of severe disease compared to boys. Despite its medical impact, the molecular mechanisms that drive AIS are largely unknown. We previously defined a female-specific AIS genetic risk locus in an enhancer near the PAX1 gene. Here, we sought to define the roles of PAX1 and newly identified AIS-associated genes in the developmental mechanism of AIS. In a genetic study of 10,519 individuals with AIS and 93,238 unaffected controls, significant association was identified with a variant in COL11A1 encoding collagen (α1) XI (rs3753841; NM_080629.2_c.4004C>T; p.(Pro1335Leu); p=7.07E-11, OR = 1.118). Using CRISPR mutagenesis we generated Pax1 knockout mice (Pax1-/-). In postnatal spines we found that PAX1 and collagen (α1) XI protein both localize within the intervertebral disc-vertebral junction region encompassing the growth plate, with less collagen (α1) XI detected in Pax1-/- spines compared to wild-type. By genetic targeting we found that wild-type Col11a1 expression in costal chondrocytes suppresses expression of Pax1 and of Mmp3, encoding the matrix metalloproteinase 3 enzyme implicated in matrix remodeling. However, the latter suppression was abrogated in the presence of the AIS-associated COL11A1P1335L mutant. Further, we found that either knockdown of the estrogen receptor gene Esr2 or tamoxifen treatment significantly altered Col11a1 and Mmp3 expression in chondrocytes. We propose a new molecular model of AIS pathogenesis wherein genetic variation and estrogen signaling increase disease susceptibility by altering a PAX1-COL11a1-MMP3 signaling axis in spinal chondrocytes.


Adolescent idiopathic scoliosis (AIS) is a twisting deformity of the spine that occurs during periods of rapid growth in children worldwide. Children with severe cases of AIS require surgery to stop it from getting worse, presenting a significant financial burden to health systems and families. Although AIS is known to cluster in families, its genetic causes and its inheritance pattern have remained elusive. Additionally, AIS is known to be more prevalent in females, a bias that has not been explained. Advances in techniques to study the genetics underlying diseases have revealed that certain variations that increase the risk of AIS affect cartilage and connective tissue. In humans, one such variation is near a gene called Pax1, and it is female-specific. The extracellular matrix is a network of proteins and other molecules in the space between cells that help connect tissues together, and it is particularly important in cartilage and other connective tissues. One of the main components of the extracellular matrix is collagen. Yu, Kanshour, Ushiki et al. hypothesized that changes in the extracellular matrix could affect the cartilage and connective tissues of the spine, leading to AIS. To show this, the scientists screened over 100,000 individuals and found that AIS is associated with variants in two genes coding for extracellular matrix proteins. One of these variants was found in a gene called Col11a1, which codes for one of the proteins that makes up collagen. To understand the relationship between Pax1 and Col11a1, Yu, Kanshour, Ushiki et al. genetically modified mice so that they would lack the Pax1 gene. In these mice, the activation of Col11a1 was reduced in the mouse spine. They also found that the form of Col11a1 associated with AIS could not suppress the activation of a gene called Mmp3 in mouse cartilage cells as effectively as unmutated Col11a1. Going one step further, the researchers found that lowering the levels of an estrogen receptor altered the activation patterns of Pax1, Col11a1, and Mmp3 in mouse cartilage cells. These findings suggest a possible mechanism for AIS, particularly in females. The findings of Yu, Kanshour, Ushiki et al. highlight that cartilage cells in the spine are particularly relevant in AIS. The results also point to specific molecules within the extracellular matrix as important for maintaining proper alignment in the spine when children are growing rapidly. This information may guide future therapies aimed at maintaining healthy spinal cells in adolescent children, particularly girls.


Subject(s)
Scoliosis , Male , Animals , Child , Mice , Humans , Female , Adolescent , Scoliosis/genetics , Matrix Metalloproteinase 3/genetics , Spine , Transcription Factors/genetics , Collagen/genetics , Genetic Variation , Collagen Type XI/genetics
17.
J Biol Chem ; 300(1): 105545, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38072056

ABSTRACT

Neurodegenerative tauopathies such as Alzheimer's disease (AD) are caused by brain accumulation of tau assemblies. Evidence suggests tau functions as a prion, and cells and animals can efficiently propagate unique, transmissible tau pathologies. This suggests a dedicated cellular replication machinery, potentially reflecting a normal physiologic function for tau seeds. Consequently, we hypothesized that healthy control brains would contain seeding activity. We have recently developed a novel monoclonal antibody (MD3.1) specific for tau seeds. We used this antibody to immunopurify tau from the parietal and cerebellar cortices of 19 healthy subjects without any neuropathology, ranging 19 to 65 years. We detected seeding in lysates from the parietal cortex, but not in the cerebellum. We also detected no seeding in brain homogenates from wildtype or human tau knockin mice, suggesting that cellular/genetic context dictates development of seed-competent tau. Seeding did not correlate with subject age or brain tau levels. We confirmed our essential findings using an orthogonal assay, real-time quaking-induced conversion, which amplifies tau seeds in vitro. Dot blot analyses revealed no AT8 immunoreactivity above background levels in parietal and cerebellar extracts and ∼1/100 of that present in AD. Based on binding to a panel of antibodies, the conformational characteristics of control seeds differed from AD, suggesting a unique underlying assembly, or structural ensemble. Tau's ability to adopt self-replicating conformations under nonpathogenic conditions may reflect a normal function that goes awry in disease states.


Subject(s)
Alzheimer Disease , Tauopathies , Animals , Humans , Mice , Alzheimer Disease/metabolism , Brain/metabolism , Cerebellum/metabolism , tau Proteins/genetics , tau Proteins/metabolism , Tauopathies/metabolism , Male , Female , Young Adult , Adult , Middle Aged , Aged
18.
Mod Pathol ; 37(2): 100398, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38043788

ABSTRACT

Immunohistochemistry (IHC) is a well-established and commonly used staining method for clinical diagnosis and biomedical research. In most IHC images, the target protein is conjugated with a specific antibody and stained using diaminobenzidine (DAB), resulting in a brown coloration, whereas hematoxylin serves as a blue counterstain for cell nuclei. The protein expression level is quantified through the H-score, calculated from DAB staining intensity within the target cell region. Traditionally, this process requires evaluation by 2 expert pathologists, which is both time consuming and subjective. To enhance the efficiency and accuracy of this process, we have developed an automatic algorithm for quantifying the H-score of IHC images. To characterize protein expression in specific cell regions, a deep learning model for region recognition was trained based on hematoxylin staining only, achieving pixel accuracy for each class ranging from 0.92 to 0.99. Within the desired area, the algorithm categorizes DAB intensity of each pixel as negative, weak, moderate, or strong staining and calculates the final H-score based on the percentage of each intensity category. Overall, this algorithm takes an IHC image as input and directly outputs the H-score within a few seconds, significantly enhancing the speed of IHC image analysis. This automated tool provides H-score quantification with precision and consistency comparable to experienced pathologists but at a significantly reduced cost during IHC diagnostic workups. It holds significant potential to advance biomedical research reliant on IHC staining for protein expression quantification.


Subject(s)
Deep Learning , Humans , Immunohistochemistry , Hematoxylin/metabolism , Algorithms , Cell Nucleus/metabolism
19.
Sci Rep ; 13(1): 22456, 2023 12 17.
Article in English | MEDLINE | ID: mdl-38105253

ABSTRACT

Prosthetic joint infection (PJI) is a complication of arthroplasty that results in significant morbidity. The presence of biofilm makes treatment difficult, and removal of the prosthesis is frequently required. We have developed a non-invasive approach for biofilm eradication from metal implants using intermittent alternating magnetic fields (iAMF) to generate targeted heating at the implant surface. The goal of this study was to determine whether iAMF demonstrated efficacy in an in vivo implant biofilm infection model. iAMF combined with antibiotics led to enhanced reduction of biofilm on metallic implants in vivo compared to antibiotics or untreated control. iAMF-antibiotic combinations resulted in a > 1 - log further reduction in biofilm burden compared to antibiotics or iAMF alone. This combination effect was seen in both S. aureus and P. aeruginosa and seen with multiple antibiotics used to treat infections with these pathogens. In addition, efficacy was temperature dependent with increasing temperatures resulting in a greater reduction of biofilm. Tissue damage was limited (< 1 mm from implant-tissue interface). This non-invasive approach to eradicating biofilm could serve as a new paradigm in treating PJI.


Subject(s)
Prosthesis-Related Infections , Humans , Prosthesis-Related Infections/drug therapy , Staphylococcus aureus , Biofilms , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Metals , Magnetic Fields
20.
Commun Biol ; 6(1): 1154, 2023 11 13.
Article in English | MEDLINE | ID: mdl-37957247

ABSTRACT

Mosquitoes shift from detritus-feeding larvae to blood-feeding adults that can vector pathogens to humans and other vertebrates. The sugar and blood meals adults consume are rich in carbohydrates and protein but are deficient in other nutrients including B vitamins. Facultatively hematophagous insects like mosquitoes have been hypothesized to avoid B vitamin deficiencies by carryover of resources from the larval stage. However, prior experimental studies have also used adults with a gut microbiota that could provision B vitamins. Here, we used Aedes aegypti, which is the primary vector of dengue virus (DENV), to ask if carryover effects enable normal function in adults with no microbiota. We show that adults with no gut microbiota produce fewer eggs, live longer with lower metabolic rates, and exhibit reduced DENV vector competence but are rescued by provisioning B vitamins or recolonizing the gut with B vitamin autotrophs. We conclude carryover effects do not enable normal function.


Subject(s)
Aedes , Dengue Virus , Gastrointestinal Microbiome , Vitamin B Complex , Animals , Fertility , Larva , Longevity , Mosquito Vectors
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