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1.
Front Physiol ; 15: 1379977, 2024.
Article in English | MEDLINE | ID: mdl-38841209

ABSTRACT

Ants are capable of learning long visually guided foraging routes with limited neural resources. The visual scene memory needed for this behaviour is mediated by the mushroom bodies; an insect brain region important for learning and memory. In a visual navigation context, the mushroom bodies are theorised to act as familiarity detectors, guiding ants to views that are similar to those previously learned when first travelling along a foraging route. Evidence from behavioural experiments, computational studies and brain lesions all support this idea. Here we further investigate the role of mushroom bodies in visual navigation with a spiking neural network model learning complex natural scenes. By implementing these networks in GeNN-a library for building GPU accelerated spiking neural networks-we were able to test these models offline on an image database representing navigation through a complex outdoor natural environment, and also online embodied on a robot. The mushroom body model successfully learnt a large series of visual scenes (400 scenes corresponding to a 27 m route) and used these memories to choose accurate heading directions during route recapitulation in both complex environments. Through analysing our model's Kenyon cell (KC) activity, we were able to demonstrate that KC activity is directly related to the respective novelty of input images. Through conducting a parameter search we found that there is a non-linear dependence between optimal KC to visual projection neuron (VPN) connection sparsity and the length of time the model is presented with an image stimulus. The parameter search also showed training the model on lower proportions of a route generally produced better accuracy when testing on the entire route. We embodied the mushroom body model and comparator visual navigation algorithms on a Quanser Q-car robot with all processing running on an Nvidia Jetson TX2. On a 6.5 m route, the mushroom body model had a mean distance to training route (error) of 0.144 ± 0.088 m over 5 trials, which was performance comparable to standard visual-only navigation algorithms. Thus, we have demonstrated that a biologically plausible model of the ant mushroom body can navigate complex environments both in simulation and the real world. Understanding the neural basis of this behaviour will provide insight into how neural circuits are tuned to rapidly learn behaviourally relevant information from complex environments and provide inspiration for creating bio-mimetic computer/robotic systems that can learn rapidly with low energy requirements.

2.
J Clin Oncol ; : JCO2301680, 2024 Jun 18.
Article in English | MEDLINE | ID: mdl-38889377

ABSTRACT

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.Observational studies have associated aspirin or cyclooxygenase 2 (COX-2) inhibitor usage either before or after colorectal cancer diagnosis with lower risk of recurrence and suggest that PIK3CA mutational status is predictive of better response to COX-2 inhibition. To prospectively test whether adding the COX-2 inhibitor celecoxib to standard adjuvant chemotherapy reduces the risk of recurrence and improves survival, the National Cancer Institute sponsored the CALGB/SWOG 80702 trial (ClinicalTrials.gov identifier: NCT01150045) for patients with stage III resected colon cancer. Although the primary hypothesis for all patients did not show a statistically significant improvement in disease-free survival (DFS) with celecoxib, subgroup analysis by PIK3CA mutational status was a preplanned study. PIK3CA gain-of-function mutations were detected in 259 of 1,197 tumors with available whole-exome sequencing data. When stratified by PIK3CA status, patients with PIK3CA gain-of-function mutations treated with celecoxib exhibited improved DFS (adjusted hazard ratio [HR], 0.56 [95% CI, 0.33 to 0.96]) compared with PIK3CA wildtype patients (adjusted HR, 0.89 [95% CI, 0.70 to 1.14]), although the interaction test was nonsignificant (Pinteraction = .13). Overall survival was similarly improved for patients with PIK3CA gain-of-function mutations (adjusted HR, 0.44 [95% CI, 0.22 to 0.85]) compared with PIK3CA wildtype patients (adjusted HR, 0.94 [95% CI, 0.68 to 1.30]; Pinteraction = .04). Although the test for heterogeneity in DFS did not reach statistical significance, the results suggest potential utility of PIK3CA to consider selective usage of COX-2 inhibitors in addition to standard treatment for stage III colon cancer.

3.
Cureus ; 16(5): e59535, 2024 May.
Article in English | MEDLINE | ID: mdl-38826981

ABSTRACT

Purpose We sought to explore the feasibility of using the current co-planar Halcyon ring delivery system (RDS) with a novel multileaf collimator (MLC) aperture shape controller in delivering a single high dose of 30 Gy to solitary lung lesions via stereotactic body radiotherapy (SBRT). Materials and methods Thirteen non-small-cell lung cancer (NSCLC) patients previously treated with a single dose of 30 Gy to lung lesions via SBRT on the TrueBeam (6MV-FFF) using non-coplanar volumetric modulated arc therapy (VMAT) arcs were anonymized and replanned onto the Halcyon RDS (6MV-FFF) following RTOG-0915 single-fraction criteria. The Halcyon plans utilized a novel dynamic conformal arc (DCA)-based MLC-fitting approach before VMAT optimization with a user-defined aperture shape controller option. The clinical TrueBeam and Halcyon plans were compared via their protocol compliance, target conformity, gradient index, and dose to organs-at-risk (OAR). Treatment delivery efficacy and accuracy were assessed through end-to-end quality assurance (QA) tests on Halcyon and independent dose verification via in-house Monte Carlo (MC) second-check validation. Results All Halcyon lung SBRT plans met RTOG-0915 protocol's requirements for target coverage, conformity, and gradient indices, and maximum dose 2 cm away from the target (D2cm) while being statistically insignificant (p > 0.05) when compared to clinical TrueBeam plans. Additionally, Halcyon provided a similar dose to OAR except for the ribs, where Halcyon demonstrated a lower maximum dose (15.22 Gy vs 17.01 Gy, p < 0.001). However, Halcyon plans required a higher total monitor unit (8892 MU vs 7413 MU, p < 0.001), resulting in a higher beam modulation factor (2.96 MU/cGy vs 2.47 MU/cGy, p < 0.001) and an increase in beam-on time by a factor of 2.1 (11.11 min vs 5.3 min, p < 0.005). End-to-end QA measurements demonstrate that Halcyon plans were clinically acceptable with an average gamma passing rate of 99.8% for 2%/2mm criteria and independent MC 2nd checks within ±2.86%. Conclusion Our end-to-end testing and validation study demonstrates that by utilizing a DCA-based MLC aperture shape controller before VMAT optimization, Halcyon can be used for delivering a single dose of lung SBRT treatment. However, future improvements of Halcyon RDS are recommended to allow higher output rates, rotational couch corrections, and an integrated intrafraction motion management system that will further enhance Halcyon's capability for site-specific single dosage of SBRT.

4.
F S Sci ; 2024 Jun 26.
Article in English | MEDLINE | ID: mdl-38942387

ABSTRACT

OBJECTIVE: To study the identification of rare genetic variants in the PCDH genetic family in a cohort of transgender women and their potential role in gender identity. DESIGN: Exome sequencing and functional ontology analysis. SETTING: Augusta University, including the Equality Clinic of Augusta and the Reproductive Medicine and Infertility Associates Clinic. PATIENTS: 24 transgender women and 22 cisgender men. INTERVENTIONS: Exome sequencing followed by variant confirmation through Sanger sequencing and functional classification analysis using the Database for Annotation, Visualization and Integrated Discovery (DAVID) tool. MAIN OUTCOME MEASURES: Identification of rare, functionally significant genetic variants in the PCDH gene family and their prevalence in transgender women compared to cisgender men. RESULTS: Exome sequencing revealed 38,524 genetic variants, of which 2441 were rare and predicted to be functionally significant. DAVID analysis demonstrated a statistically enriched functional group, "homophilic cell adhesion via plasma membrane adhesion molecules" (Benjamini corrected p-value 1.5 x 10-11), containing 55 genes, including 18 PCDH gene family members. A total of 37 rare variants in 21 PCDH genes were identified, with 36 confirmed by Sanger sequencing. A statistically significant increase in these variants was observed in transgender women compared to cisgender men (Z = 2.08905, p= 0.037). CONCLUSIONS: Transgender women exhibited a greater than 3-fold increase in functionally significant PCDH gene variants compared to cisgender men. These findings suggest that the PCDH family may play a role in the genetic pathways associated with gender identity in transgender women.

5.
Bioconjug Chem ; 35(6): 715-731, 2024 Jun 19.
Article in English | MEDLINE | ID: mdl-38775705

ABSTRACT

Click chemistry has become a commonly used synthetic method due to the simplicity, efficiency, and high selectivity of this class of chemical reactions. Since their initial discovery, further click chemistry methods have been identified and added to the toolbox of click chemistry reactions for biomedical applications. However, selecting the most suitable reaction for a specific application is often challenging, as multiple factors must be considered, including selectivity, reactivity, biocompatibility, and stability. Thus, this review provides an overview of the benefits and limitations of well-established click chemistry reactions with a particular focus on the importance of considering reaction rates, an often overlooked criterion with little available guidance. The importance of understanding each click chemistry reaction beyond simply the reaction speed is discussed comprehensively with reference to recent biomedical research which utilized click chemistry. This review aims to provide a practical resource for researchers to guide the selection of click chemistry classes for different biomedical applications.


Subject(s)
Click Chemistry , Click Chemistry/methods , Humans , Animals , Biomedical Research/methods
6.
Mol Cell Endocrinol ; 589: 112237, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38599276

ABSTRACT

The molecular basis of mullerian aplasia, also known as Mayer-Rokitansky-Kuster Hauser (MRKH) or congenital absence of the uterus and vagina, is largely unknown. We applied a multifaceted genetic approach to studying the pathogenesis of MRKH including exome sequencing of trios and duos, genome sequencing of families, qPCR, RT-PCR, and Sanger sequencing to detect intragenic deletions, insertions, splice variants, single nucleotide variants, and rearrangements in 132 persons with MRKH. We identified two heterozygous variants in ZNHIT3 localized to a commonly involved CNV region at chromosome 17q12 in two different families with MRKH. One is a frameshift, truncating variant that is predicted to interfere with steroid hormone binding of the LxxLL sequence of the C-terminal region. The second variant is a double missense/stopgain variant. Both variants impair protein expression in vitro. In addition, four more probands with MRKH harbored the stopgain variant without the nearby missense variant. In total, 6/132 (4.5%) of patients studied, including five with associated anomalies (type 2 MRKH), had ZNHIT3 variants that impair function in vitro. Our findings implicate ZNHIT3 as an important gene associated with MRKH within the 17q12 CNV region.


Subject(s)
46, XX Disorders of Sex Development , Chromosomes, Human, Pair 17 , Congenital Abnormalities , Heterozygote , Mullerian Ducts , Adolescent , Adult , Female , Humans , 46, XX Disorders of Sex Development/genetics , Chromosomes, Human, Pair 17/genetics , Congenital Abnormalities/genetics , Mullerian Ducts/abnormalities , Pedigree
7.
Res Sq ; 2024 Mar 21.
Article in English | MEDLINE | ID: mdl-38562857

ABSTRACT

Calorie restriction (CR) provides anti-aging benefits through diverse processes, such as reduced metabolism and growth and increased mitochondrial activity. Although controversy still exists regarding CR-mediated lifespan effects, many researchers are seeking interventions that mimic the effects of CR. Yeast has proven to be a useful model system for aging studies, including CR effects. We report here that yeast adapted through in vitro evolution to the severe cellular stress caused by loss of the Ulp2 SUMO-specific protease exhibit both enhanced growth rates and replicative lifespan, and they have altered gene expression profiles similar to those observed in CR. Notably, in certain evolved ulp2Δ lines, a dramatic increase in the auto-sumoylation of Ubc9 E2 SUMO-conjugating enzyme results in altered regulation of multiple targets involved in energy metabolism and translation at both transcriptional and post-translational levels. This increase is essential for the survival of aged cells and CR-mediated lifespan extension. Thus, we suggest that high Ubc9 auto-sumoylation exerts potent anti-aging effects by promoting efficient energy metabolism-driven improvements in cell replication abilities. This potential could be therapeutically explored for the development of novel CR-mimetic strategies.

8.
Article in English | MEDLINE | ID: mdl-38485057

ABSTRACT

BACKGROUND: MUPPITS-2 was a randomized, placebo-controlled clinical trial that demonstrated mepolizumab (anti-IL-5) reduced exacerbations and blood and airway eosinophils in urban children with severe eosinophilic asthma. Despite this reduction in eosinophilia, exacerbation risk persisted in certain patients treated with mepolizumab. This raises the possibility that subpopulations of airway eosinophils exist that contribute to breakthrough exacerbations. OBJECTIVE: We aimed to determine the effect of mepolizumab on airway eosinophils in childhood asthma. METHODS: Sputum samples were obtained from 53 MUPPITS-2 participants. Airway eosinophils were characterized using mass cytometry and grouped into subpopulations using unsupervised clustering analyses of 38 surface and intracellular markers. Differences in frequency and immunophenotype of sputum eosinophil subpopulations were assessed based on treatment arm and frequency of exacerbations. RESULTS: Median sputum eosinophils were significantly lower among participants treated with mepolizumab compared with placebo (58% lower, 0.35% difference [95% CI 0.01, 0.74], P = .04). Clustering analysis identified 3 subpopulations of sputum eosinophils with varied expression of CD62L. CD62Lint and CD62Lhi eosinophils exhibited significantly elevated activation marker and eosinophil peroxidase expression, respectively. In mepolizumab-treated participants, CD62Lint and CD62Lhi eosinophils were more abundant in participants who experienced exacerbations than in those who did not (100% higher for CD62Lint, 0.04% difference [95% CI 0.0, 0.13], P = .04; 93% higher for CD62Lhi, 0.21% difference [95% CI 0.0, 0.77], P = .04). CONCLUSIONS: Children with eosinophilic asthma treated with mepolizumab had significantly lower sputum eosinophils. However, CD62Lint and CD62Lhi eosinophils were significantly elevated in children on mepolizumab who had exacerbations, suggesting that eosinophil subpopulations exist that contribute to exacerbations despite anti-IL-5 treatment.

9.
Sci Rep ; 14(1): 633, 2024 01 05.
Article in English | MEDLINE | ID: mdl-38182623

ABSTRACT

Synaptophysin is expressed on fibrogenic hepatic myofibroblasts. C1-3 is a single chain human antibody (scAb) that binds specifically to synaptophysin on hepatic myofibroblasts, providing a targeting vector for novel in vivo imaging agents of chronic liver disease. C1-3 and a negative control scAb, CSBD9, were radiolabelled with zirconium-89 via desferrioxamine chelation to enable non-invasive molecular imaging with positron emission tomography (PET). DFO-scAb conjugates were characterised by gel electrophoresis (SDS-PAGE) and MALDI-TOF spectrometry, and 89Zr-labelled with high radiolabelling efficiency (99%). [89Zr]Zr-DFO-C1-3 exhibited high in vitro stability (> 99%) in mouse and human sera over 3 days at 25 and 37 °C. Activated hepatic myofibroblasts incubated with [89Zr]Zr-DFO-C1-3 displayed significantly higher internalised activity (59.46%, P = 0.001) compared to the [89Zr]Zr-DFO-CSBD9 control, indicating synaptophysin-mediated uptake and high binding specificity of [89Zr]Zr-DFO-C1-3. Mice with CCl4-induced acute liver damage exhibited significantly higher liver uptake of [89Zr]Zr-DFO-C1-3, compared to controls, confirmed by both Cerenkov imaging and ex vivo gamma counting (4.41 ± 0.19%ID/g, P < 0.0001). CCl4-induced liver damage and the number of hepatic myofibroblasts was confirmed by αSMA staining of liver sections. These findings indicate that [89Zr]Zr-DFO-C1-3 has promising utility as a PET imaging agent for non-invasive detection of hepatic myofibroblasts following acute liver injury.


Subject(s)
Myofibroblasts , Tomography, X-Ray Computed , Humans , Animals , Mice , Synaptophysin , Liver/diagnostic imaging , Immunoglobulins
10.
Blood ; 143(11): 1032-1044, 2024 Mar 14.
Article in English | MEDLINE | ID: mdl-38096369

ABSTRACT

ABSTRACT: Extreme disease phenotypes can provide key insights into the pathophysiology of common conditions, but studying such cases is challenging due to their rarity and the limited statistical power of existing methods. Herein, we used a novel approach to pathway-based mutational burden testing, the rare variant trend test (RVTT), to investigate genetic risk factors for an extreme form of sepsis-induced coagulopathy, infectious purpura fulminans (PF). In addition to prospective patient sample collection, we electronically screened over 10.4 million medical records from 4 large hospital systems and identified historical cases of PF for which archived specimens were available to perform germline whole-exome sequencing. We found a significantly increased burden of low-frequency, putatively function-altering variants in the complement system in patients with PF compared with unselected patients with sepsis (P = .01). A multivariable logistic regression analysis found that the number of complement system variants per patient was independently associated with PF after controlling for age, sex, and disease acuity (P = .01). Functional characterization of PF-associated variants in the immunomodulatory complement receptors CR3 and CR4 revealed that they result in partial or complete loss of anti-inflammatory CR3 function and/or gain of proinflammatory CR4 function. Taken together, these findings suggest that inherited defects in CR3 and CR4 predispose to the maladaptive hyperinflammation that characterizes severe sepsis with coagulopathy.


Subject(s)
Purpura Fulminans , Sepsis , Humans , Purpura Fulminans/genetics , Prospective Studies , Receptors, Complement
11.
J Neurosurg ; 140(4): 909-919, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-37877983

ABSTRACT

OBJECTIVE: Preoperative grading of nonenhancing motor eloquent gliomas is hampered by a lack of specific imaging surrogates. Tumor grading is crucial for the informed consent discussion before tumor resection. In this paper, the authors hypothesized that navigated transcranial magnetic stimulation (nTMS)-derived metrics could provide significant information to distinguish between high- and low-grade motor eloquent gliomas that present as nonenhancing tumors and therefore contribute to improving patient counseling, timing of treatment, preoperative planning, and intraoperative strategies. METHODS: The authors conducted a retrospective single-center cohort study of patients admitted for tumor surgery between January 2018 and April 2022 with a nonenhancing motor eloquent glioma and preoperative bilateral nTMS mapping. nTMS data including resting motor threshold (RMT), interhemispheric RMT ratio (iRMTr), Cortical Excitability Score (CES), area and volume of cortical activation, and motor evoked potential (MEP) characteristics were obtained and integrated with demographic and clinical data. RESULTS: Thirty patients met the inclusion criteria, and 10 healthy participants were recruited for comparison. Seizures were the most common presenting symptom (25 patients) and WHO grade 3 the most common tumor grade (21 patients). The area and volume of functional cortical activation of both the abductor pollicis brevis and first dorsal interosseous muscles were decreased in healthy participants compared with patients with WHO grade 3 glioma (p < 0.05). An abnormal iRMTr for the lower limbs (16.7% [1/6] WHO grade 2, 76.2% [16/21] WHO grade 3, 100% [3/3] WHO grade 4; p = 0.015) and a higher CES (maximal abnormal CES: 0% [0/6] WHO grade 2, 38% [8/21] WHO grade 3, 66.7% [2/3] WHO grade 4; p = 0.010) were associated with the prediction of high-grade lesions. A total of 7280 MEPs were analyzed. A significant increase in the amplitude and a significant decrease in latency in the MEPs for the first dorsal interosseous and abductor digiti minimi muscles (p < 0.0001) were identified in healthy participants compared with WHO grade 3 glioma patients. CONCLUSIONS: Nonenhancing motor eloquent gliomas have a different impact on both anatomical and functional reorganization of motor areas according to their WHO grading.


Subject(s)
Brain Neoplasms , Glioma , Humans , Transcranial Magnetic Stimulation/methods , Brain Neoplasms/diagnostic imaging , Brain Neoplasms/surgery , Brain Neoplasms/pathology , Cohort Studies , Retrospective Studies , Glioma/diagnostic imaging , Glioma/surgery , Brain Mapping/methods , Neuronavigation/methods , Evoked Potentials, Motor
12.
ACS Omega ; 8(50): 47905-47912, 2023 Dec 19.
Article in English | MEDLINE | ID: mdl-38144136

ABSTRACT

Secondary Cerenkov-induced fluorescence imaging (SCIFI) is an emerging biomedical optical imaging modality that leverages Cerenkov luminescence, primarily generated by ß-emitting radioisotopes, to excite fluorophores that offer near-infrared emissions with optimal tissue penetrance. Dual-functionalized immunoconjugates composed of an antibody, a near-infrared fluorophore, and a ß-emitting radioisotope have potential utility as novel SCIFI constructs with high specificity for molecular biomarkers of disease. Here, we report the synthesis and characterization of [89Zr]Zr-DFO-trastuzumab-BOD665, a self-excitatory HER2-specific "immunoSCIFI" probe capable of yielding near-infrared fluorescence in situ without external excitation. The penetration depth of the SCIFI signal was measured in hemoglobin-infused optical tissue phantoms that indicated a 2.05-fold increase compared to 89Zr-generated Cerenkov luminescence. Additionally, the binding specificity of the immunoSCIFI probe for HER2 was evaluated in a cellular assay that showed significantly higher binding to SKBR3 (high HER2 expression) relative to MDA-MB-468 (low HER2) breast cancer cells based on measurements of total flux in the near-infrared region with external excitation blocked. Taken together, the results of this study indicate the potential utility of immunoSCIFI constructs for interrogation of molecular biomarkers of disease.

13.
bioRxiv ; 2023 Nov 15.
Article in English | MEDLINE | ID: mdl-38014178

ABSTRACT

Obesity-linked fatty liver is a significant risk factor for hepatocellular carcinoma (HCC)1,2; however, the molecular mechanisms underlying the transition from non-alcoholic fatty liver disease (NAFLD) to HCC remains unclear. The present study explores the role of the endoplasmic reticulum (ER)-associated protein NgBR, an essential component of the cis-prenyltransferases (cis-PTase) enzyme3, in chronic liver disease. Here we show that genetic depletion of NgBR in hepatocytes of mice (N-LKO) intensifies triacylglycerol (TAG) accumulation, inflammatory responses, ER/oxidative stress, and liver fibrosis, ultimately resulting in HCC development with 100% penetrance after four months on a high-fat diet. Comprehensive genomic and single cell transcriptomic atlas from affected livers provides a detailed molecular analysis of the transition from liver pathophysiology to HCC development. Importantly, pharmacological inhibition of diacylglycerol acyltransferase-2 (DGAT2), a key enzyme in hepatic TAG synthesis, abrogates diet-induced liver damage and HCC burden in N-LKO mice. Overall, our findings establish NgBR/cis-PTase as a critical suppressor of NAFLD-HCC conversion and suggests that DGAT2 inhibition may serve as a promising therapeutic approach to delay HCC formation in patients with advanced non-alcoholic steatohepatitis (NASH).

14.
Nat Commun ; 14(1): 6279, 2023 10 07.
Article in English | MEDLINE | ID: mdl-37805627

ABSTRACT

Hedgehog signaling mediates embryologic development of the central nervous system and other tissues and is frequently hijacked by neoplasia to facilitate uncontrolled cellular proliferation. Meningiomas, the most common primary brain tumor, exhibit Hedgehog signaling activation in 6.5% of cases, triggered by recurrent mutations in pathway mediators such as SMO. In this study, we find 35.6% of meningiomas that lack previously known drivers acquired various types of somatic structural variations affecting chromosomes 2q35 and 7q36.3. These cases exhibit ectopic expression of Hedgehog ligands, IHH and SHH, respectively, resulting in Hedgehog signaling activation. Recurrent tandem duplications involving IHH permit de novo chromatin interactions between super-enhancers within DIRC3 and a locus containing IHH. Our work expands the landscape of meningioma molecular drivers and demonstrates enhancer hijacking of Hedgehog ligands as a route to activate this pathway  in neoplasia.


Subject(s)
Meningeal Neoplasms , Meningioma , Humans , Hedgehog Proteins/genetics , Hedgehog Proteins/metabolism , Meningioma/genetics , Ligands , Signal Transduction , Meningeal Neoplasms/genetics
15.
Curr Biol ; 33(20): 4392-4404.e5, 2023 10 23.
Article in English | MEDLINE | ID: mdl-37776861

ABSTRACT

Many animals use motion vision information to control dynamic behaviors. Predatory animals, for example, show an exquisite ability to detect rapidly moving prey, followed by pursuit and capture. Such target detection is not only used by predators but is also important in conspecific interactions, such as for male hoverflies defending their territories against conspecific intruders. Visual target detection is believed to be subserved by specialized target-tuned neurons found in a range of species, including vertebrates and arthropods. However, how these target-tuned neurons respond to actual pursuit trajectories is currently not well understood. To redress this, we recorded extracellularly from target-selective descending neurons (TSDNs) in male Eristalis tenax hoverflies. We show that they have dorso-frontal receptive fields with a preferred direction up and away from the visual midline. We reconstructed visual flow fields as experienced during pursuits of artificial targets (black beads). We recorded TSDN responses to six reconstructed pursuits and found that each neuron responded consistently at remarkably specific time points but that these time points differed between neurons. We found that the observed spike probability was correlated with the spike probability predicted from each neuron's receptive field and size tuning. Interestingly, however, the overall response rate was low, with individual neurons responding to only a small part of each reconstructed pursuit. In contrast, the TSDN population responded to substantially larger proportions of the pursuits but with lower probability. This large variation between neurons could be useful if different neurons control different parts of the behavioral output.


Subject(s)
Diptera , Motion Perception , Animals , Male , Motion Perception/physiology , Neurons/physiology , Visual Fields , Vision, Ocular , Diptera/physiology , Photic Stimulation
16.
J Neurosurg Spine ; 39(4): 583-592, 2023 10 01.
Article in English | MEDLINE | ID: mdl-37486861

ABSTRACT

OBJECTIVE: Lumbar spine decompression surgery, in the form of laminectomy or discectomy, is known to be effective in improving symptoms of radiculopathy and neurogenic claudication. However, it is less clear how it impacts coexisting low-back pain (LBP). The aim of this study was to quantify the change in LBP after lumbar decompression. METHODS: This study analyzed data from the British Spine Registry on patients who underwent lumbar decompression surgery. LBP severity was assessed using the visual analog scale (VAS), and the primary outcome was the change in VAS score at 1 year, with secondary outcomes measuring the change in score at 6 weeks, 6 months, and 2 years. The minimal clinically important difference (MCID) was defined as a 30% reduction in pain. RESULTS: Of the 25,349 patients included in the study, 92.2% reported significant back pain at baseline. Of the entire cohort, 12,951 (55.4%) patients had follow-up data for 6 weeks, 9066 (38.8%) for 6 months, 7926 (33.9%) for 1 year, and 5517 (23.6%) for 2 years; 17,304 (68.3%) patients had follow-up data for at least one time point. Sixty-two percent of patients attained the MCID (VAS score ≥ 30%) in back pain reduction, with 51% reporting a substantial improvement (VAS score ≥ 50%). This improvement was observed by 6 weeks postoperation and was mostly maintained at 2 years. Patients with back pain predominance were more likely to attain the MCID compared with those with leg pain predominance (63.6% vs 60.1%; OR 1.16, 95% CI 1.02-1.34; p = 0.0291). Severity of baseline back pain did not reduce the proportion attaining the MCID. CONCLUSIONS: Regardless of pain presentation, LBP improves in approximately 62% of patients who undergo lumbar decompressive surgery, with 51% experiencing substantial improvement. Patients undergoing lumbar decompression can be advised on the chance of a meaningful improvement in back pain postsurgery.


Subject(s)
Low Back Pain , Radiculopathy , Spinal Stenosis , Humans , Lumbar Vertebrae/surgery , Low Back Pain/surgery , Back Pain/surgery , Radiculopathy/surgery , Registries , Treatment Outcome , Spinal Stenosis/complications , Spinal Stenosis/surgery , Decompression, Surgical
17.
Front Cell Infect Microbiol ; 13: 1198115, 2023.
Article in English | MEDLINE | ID: mdl-37434783

ABSTRACT

Introduction: Infection in diabetic foot ulcers (DFUs) is one of the major complications associated with patients with diabetes. Staphylococcus aureus is the most common offending pathogen in patients with infected DFU. Previous studies have suggested the application of species-specific antibodies against S. aureus for diagnosis and monitoring treatment response. Early and accurate identification of the main pathogen is critical for management of DFU infection. Understanding the host immune response against species-specific infection may facilitate diagnosis and may suggest potential intervention options to promote healing infected DFUs. We sought to investigate evolving host transcriptome associated with surgical treatment of S. aureus- infected DFU. Methods: This study compared the transcriptome profile of 21 patients with S. aureus- infected DFU who underwent initial foot salvage therapy with irrigation and debridement followed by intravenous antibiotic therapy. Blood samples were collected at the recruitment (0 weeks) and 8 weeks after therapy to isolate peripheral blood mononuclear cells (PBMCs). We analyzed the PBMC expression of transcriptomes at two different time points (0 versus 8 weeks). Subjects were further divided into two groups at 8 weeks: healed (n = 17, 80.95%) versus non-healed (n = 4, 19.05%) based on the wound healing status. DESeq2 differential gene analysis was performed. Results and discussion: An increased expression of IGHG1, IGHG2, IGHG3, IGLV3-21, and IGLV6-57 was noted during active infection at 0 weeks compared with that at 8 weeks. Lysine- and arginine-rich histones (HIST1H2AJ, HIST1H2AL, HIST1H2BM, HIST1H3B, and HIST1H3G) were upregulated at the initial phase of active infection at 0 weeks. CD177 and RRM2 were also upregulated at the initial phase of active infection (0 weeks) compared with that at 8 weeks of follow-up. Genes of heat shock protein members (HSPA1A, HSPE1, and HSP90B1) were high in not healed patients compared with that in healed patients 8 weeks after therapy. The outcome of our study suggests that the identification of genes evolution based on a transcriptomic profiling could be a useful tool for diagnosing infection and assessing severity and host immune response to therapies.


Subject(s)
Communicable Diseases , Diabetes Mellitus , Diabetic Foot , Methicillin-Resistant Staphylococcus aureus , Humans , Transcriptome , Diabetic Foot/genetics , Leukocytes, Mononuclear , Staphylococcus aureus , Histones
18.
Cancer Genet ; 276-277: 30-35, 2023 08.
Article in English | MEDLINE | ID: mdl-37418972

ABSTRACT

We performed whole exome sequencing (WES) and microarray analysis to detect somatic variants and copy number alterations (CNAs) for underlying mechanisms in a case series of hepatocellular carcinoma (HCC) with paired DNA samples from tumor and adjacent nontumor tissues. Clinicopathologic findings based on Edmondson-Steiner (E-S) grading, Barcelona-Clinic Liver Cancer (BCLC) stages, recurrence, and survival status and their associations with tumor mutation burden (TMB) and CNA burden (CNAB) were evaluated. WES from 36 cases detected variants in the TP53, AXIN1, CTNNB1, and SMARCA4 genes, amplifications of the AKT3, MYC, and TERT genes, and deletions of the CDH1, TP53, IRF2, RB1, RPL5, and PTEN genes. These genetic defects affecting the p53/cell cycle control, PI3K/Ras, and ß-catenin pathways were observed in approximately 80% of cases. A germline variant in the ALDH2 gene was detected in 52% of the cases. Significantly higher CNAB in patients with poor prognosis by E-S grade III, BCLC stage C, and recurrence than patients with good prognosis by grade III, stage A, grade III and nonrecurrence was noted. Further analysis on a large case series to correlate genomic profiling with clinicopathologic classifications could provide evidence for diagnostic interpretation, prognostic prediction, and target intervention on involved genes and pathways.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Humans , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/pathology , Liver Neoplasms/genetics , Liver Neoplasms/pathology , Exome Sequencing , Mutation , DNA Copy Number Variations/genetics , Biomarkers, Tumor/genetics , Microarray Analysis , DNA Helicases/genetics , Nuclear Proteins/genetics , Transcription Factors/genetics , Aldehyde Dehydrogenase, Mitochondrial/genetics
20.
Obesity (Silver Spring) ; 31(4): 990-999, 2023 04.
Article in English | MEDLINE | ID: mdl-36876594

ABSTRACT

OBJECTIVE: This study assessed the effects of semaglutide on body weight, cardiometabolic risk factors, and glycemic status in individuals categorized by baseline BMI with or without additional obesity-related comorbidities, including prediabetes and high risk of cardiovascular disease (CVD). METHODS: This was a post hoc exploratory subgroup analysis of the Semaglutide Treatment Effect in People with Obesity (STEP) 1 trial (NCT03548935), in which participants without diabetes and BMI ≥30 kg/m2 , or BMI ≥27 kg/m2 with ≥1 weight-related comorbidity, were randomized to once-weekly subcutaneous semaglutide 2.4 mg or placebo for 68 weeks. For this analysis, individuals were categorized into subgroups based on baseline BMI <35 versus ≥35 kg/m2 (with no additional criteria, with ≥1 comorbidity, with prediabetes, and with prediabetes and high risk of CVD). RESULTS: Mean changes in body weight from baseline to week 68 with semaglutide were -16.2% and -14.0% in the subgroups with baseline BMI <35 and ≥35 kg/m2 , respectively (both p < 0.0001 vs. placebo). Similar changes were observed in individuals with comorbidities, with prediabetes, and with prediabetes plus high CVD risk. The beneficial effects of semaglutide on cardiometabolic risk factors were consistent across all subgroups. CONCLUSIONS: This subgroup analysis confirms that semaglutide is effective in individuals with baseline BMI <35 and ≥35 kg/m2 , including in those with comorbidities.


Subject(s)
Body Weight , Cardiovascular Diseases , Diabetes Mellitus, Type 2 , Glucagon-Like Peptides , Obesity , Humans , Glucagon-Like Peptides/administration & dosage , Glucagon-Like Peptides/therapeutic use , Comorbidity , Cardiovascular Diseases/epidemiology , Obesity/epidemiology , Body Mass Index , Body Weight/drug effects , Diabetes Mellitus, Type 2/epidemiology
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