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OBJECTIVE: Alcohol use in metabolic dysfunction-associated steatohepatitis (MASH) is associated with an increased risk of fibrosis and liver-related death. Here, we aimed to identify a mechanism through which repeated alcohol binges exacerbate liver injury in a high fat-cholesterol-sugar diet (MASH diet)-induced model of MASH. DESIGN: C57BL/6 mice received either chow or the MASH diet for 3 months with or without weekly alcohol binges. Neutrophil infiltration, neutrophil extracellular traps (NETs) and fibrosis were evaluated. RESULTS: We found that alcohol binges in MASH increase liver injury and fibrosis. Liver transcriptomic profiling revealed differential expression of genes involved in extracellular matrix reorganisation, neutrophil activation and inflammation compared with alcohol or the MASH diet alone. Alcohol binges specifically increased NET formation in MASH livers in mice, and NETs were also increased in human livers with MASH plus alcohol use. We discovered that cell-free NETs are sensed via Nod-like receptor protein 3 (NLRP3). Furthermore, we show that cell-free NETs in vitro induce a profibrotic phenotype in hepatic stellate cells (HSCs) and proinflammatory monocytes. In vivo, neutrophil depletion using anti-Ly6G antibody or NET disruption with deoxyribonuclease treatment abrogated monocyte and HSC activation and ameliorated liver damage and fibrosis. In vivo, inhibition of NLRP3 using MCC950 or NLRP3 deficiency attenuated NET formation, liver injury and fibrosis in MASH plus alcohol diet-fed mice (graphical abstract). CONCLUSION: Alcohol binges promote liver fibrosis via NET-induced activation of HSCs and monocytes in MASH. Our study highlights the potential of inhibition of NETs and/or NLRP3, as novel therapeutic strategies to combat the profibrotic effects of alcohol in MASH.
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Armadilhas Extracelulares , Células Estreladas do Fígado , Monócitos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Animais , Humanos , Masculino , Camundongos , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Etanol , Armadilhas Extracelulares/metabolismo , Furanos/farmacologia , Células Estreladas do Fígado/metabolismo , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Indenos , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Cirrose Hepática/etiologia , Camundongos Endogâmicos C57BL , Monócitos/metabolismo , Neutrófilos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Sulfonamidas/farmacologia , Sulfonas/farmacologiaRESUMO
BACKGROUND AIMS: Prolonged systemic inflammation contributes to poor clinical outcomes in severe alcohol-associated hepatitis (AH) even after the cessation of alcohol use. However, mechanisms leading to this persistent inflammation remain to be understood. APPROACH RESULTS: We show that while chronic alcohol induces nucleotide-binding oligomerization domain-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome activation in the liver, alcohol binge results not only in NLRP3 inflammasome activation but also in increased circulating extracellular apoptosis-associated speck-like protein containing a caspase recruitment domain (ex-ASC) specks and hepatic ASC aggregates both in patients with AH and in mouse models of AH. These ex-ASC specks persist in circulation even after the cessation of alcohol use. Administration of alcohol-induced-ex-ASC specks in vivo in alcohol-naive mice results in sustained inflammation in the liver and circulation and causes liver damage. Consistent with the key role of ex-ASC specks in mediating liver injury and inflammation, alcohol binge failed to induce liver damage or IL-1ß release in ASC-deficient mice. Our data show that alcohol induces ex-ASC specks in liver macrophages and hepatocytes, and these ex-ASC specks can trigger IL-1ß release in alcohol-naive monocytes, a process that can be prevented by the NLRP3 inhibitor, MCC950. In vivo administration of MCC950 reduced hepatic and ex-ASC specks, caspase-1 activation, IL-1ß production, and steatohepatitis in a murine model of AH. CONCLUSIONS: Our study demonstrates the central role of NLRP3 and ASC in alcohol-induced liver inflammation and unravels the critical role of ex-ASC specks in the propagation of systemic and liver inflammation in AH. Our data also identify NLRP3 as a potential therapeutic target in AH.
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Hepatite Alcoólica , Hepatite , Animais , Camundongos , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Hepatite/etiologia , Inflamação , Hepatite Alcoólica/etiologia , Etanol/efeitos adversos , Caspase 1/metabolismo , Interleucina-1beta/metabolismo , Proteínas Adaptadoras de Sinalização CARD/metabolismoRESUMO
BACKGROUND & AIMS: Various intracellular pathways regulate inflammation in NASH. Cyclic GMP-AMP synthase (cGAS) is a DNA sensor that activates STING and plays a role in inflammatory diseases. Here, we explored the role of cGAS in hepatic damage, steatosis, inflammation, and liver fibrosis in mouse models of NASH. METHODS: cGAS deficient (cGAS-KO) and STING deficient (STING-KO) mice received high fat-high cholesterol-high sugar diet (HF-HC-HSD) or relevant control diets. Livers were evaluated after 16 or 30 weeks. RESULTS: HF-HC-HSD diet, both at 16 and 30 weeks, resulted in increased cGAS protein expression as well as in increased ALT, IL-1ß, TNF-α and MCP-1 in wild-type (WT) mice compared to controls. Surprisingly, liver injury, triglyceride accumulation, and inflammasome activation were greater in HF-HC-HSD cGAS-KO compared to WT mice at 16 and to a lesser extent at 30 weeks. STING, a downstream target of cGAS was significantly increased in WT mice after HF-HC-HSD. In STING-KO mice after HF-HC-HSD feeding, we found increased ALT and attenuated MCP1 and IL-1ß expression compared to WT mice. Markers of liver fibrosis were increased in cGAS- and STING-KO mice compared to WT on HF-HC-HSD. We discovered that cGAS-KO mice had a significant increase in circulating endotoxin levels on HF-HC-HSD that correlated with changes in intestinal morphology which was exacerbated by HF-HC-HSD compared to WT mice. CONCLUSION: Our findings indicate that cGAS or STING deficiency exacerbate liver damage, steatosis, and inflammation in HF-HC-HSD diet-induced NASH, which might be linked to the disruption of the gut barrier.
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Hepatopatia Gordurosa não Alcoólica , Nucleotidiltransferases , Animais , Camundongos , Homeostase , Inflamação/patologia , Fígado/patologia , Cirrose Hepática/patologia , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/patologia , Nucleotidiltransferases/metabolismoRESUMO
BACKGROUND: The delay between amputation and prosthesis fitting contributes to the high rate of prosthetic abandonment despite advances in technology. Three-dimensional (3D) printing has allowed for the rapid fabrication of prostheses. Allowing individuals with amputations to interact with a prosthesis shortly after their procedure may reduce rejection chances. The purpose of the current investigation is to compare functional outcomes and patient satisfaction between a standard transradial prosthesis fitted in a clinic with a 3D-printed prosthesis fitted remotely. The standard prosthesis featured a hook terminal device, while the 3D printed prosthesis' terminal device was a functional hand. RESULTS: The main finding of this case study was that the use of a 3D printed arm prosthesis fitted remotely resulted in better functional performance, but lower overall patient satisfaction than the standard arm prosthesis. Use of the 3D printed arm resulted in improved gross manual dexterity as measured by the Box and Block test. The 3D printed prosthesis also allowed improved performance in bimanual coordination. However, the standard-hook device scored higher in patient satisfaction survey results. The patient's concerns with the 3D printed prosthesis were the durability and effectiveness of the device. CONCLUSION: While durability and complex grip patterns remain a concern, the positive attributes of 3D printed prostheses include visual appeal, ease of donning, and customization of parameters to improve upper-limb symmetry offers a promising option to familiarize new amputee patients with the use of a prosthesis. Rapid manufacturing and remote fitting allows 3D printed devices to serve as postoperative transitional devices and may function as definitive devices with minimal loss of functionality if standard clinic-based prostheses are not available. METHODS: The patient was a 59-year-old male with a traumatic transradial amputation of the dominant arm. A 3D printed transradial prosthesis was remotely fitted and manufactured using photogrammetry. Assessments were performed initially with the standard-hook prosthesis and then with the 3D printed device after a 5-week familiarization period. Functional outcomes were evaluated using the Box and Block Test and Bimanual Coordination Tray Test. Patient satisfaction was evaluated using two self-reported questionnaires (the QUEST 2.0 and the modified OPUS).
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Mãos , Satisfação do Paciente , Humanos , Masculino , Pessoa de Meia-Idade , Desempenho Físico Funcional , Impressão Tridimensional , Desenho de PróteseRESUMO
Metabolism is a fundamental process for all cellular functions. For decades, there has been growing evidence of a relationship between metabolism and malignant cell proliferation. Unlike normal differentiated cells, cancer cells have reprogrammed metabolism in order to fulfill their energy requirements. These cells display crucial modifications in many metabolic pathways, such as glycolysis and glutaminolysis, which include the tricarboxylic acid (TCA) cycle, the electron transport chain (ETC), and the pentose phosphate pathway (PPP) [1]. Since the discovery of the Warburg effect, it has been shown that the metabolism of cancer cells plays a critical role in cancer survival and growth. More recent research suggests that the involvement of glutamine in cancer metabolism is more significant than previously thought. Glutamine, a nonessential amino acid with both amine and amide functional groups, is the most abundant amino acid circulating in the bloodstream [2]. This chapter discusses the characteristic features of glutamine metabolism in cancers and the therapeutic options to target glutamine metabolism for cancer treatment.
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Glutamina , Neoplasias , Ciclo do Ácido Cítrico , Metabolismo Energético , Glutamina/metabolismo , Glicólise , Humanos , Redes e Vias MetabólicasRESUMO
BACKGROUND: The purpose of the current study was to determine the influence of upper-limb prostheses on brain activity and gross dexterity in children with congenital unilateral upper-limb reduction deficiencies (ULD) compared to typically developing children (TD). METHODS: Five children with ULD (3 boys, 2 girls, 8.76 ± 3.37 years of age) and five age- and sex-matched TD children (3 boys, 2 girls, 8.96 ± 3.23 years of age) performed a gross manual dexterity task (Box and Block Test) while measuring brain activity (functional near-infrared spectroscopy; fNIRS). RESULTS: There were no significant differences (p = 0.948) in gross dexterity performance between the ULD group with prosthesis (7.23 ± 3.37 blocks per minute) and TD group with the prosthetic simulator (7.63 ± 5.61 blocks per minute). However, there was a significant (p = 0.001) difference in Laterality Index (LI) between the ULD group with prosthesis (LI = - 0.2888 ± 0.0205) and TD group with simulator (LI = 0.0504 ± 0.0296) showing in a significant ipsilateral control for the ULD group. Thus, the major finding of the present investigation was that children with ULD, unlike the control group, showed significant activation in the ipsilateral motor cortex on the non-preferred side using a prosthesis during a gross manual dexterity task. CONCLUSIONS: This ipsilateral response may be a compensation strategy in which the existing cortical representations of the non-affected (preferred) side are been used by the affected (non-preferred) side to operate the prosthesis. This study is the first to report altered lateralization in children with ULD while using a prosthesis. Trial registration The clinical trial (ClinicalTrial.gov ID: NCT04110730 and unique protocol ID: IRB # 614-16-FB) was registered on October 1, 2019 ( https://clinicaltrials.gov/ct2/show/NCT04110730 ) and posted on October 1, 2019. The study start date was January 10, 2020. The first participant was enrolled on January 14, 2020, and the trial is scheduled to be completed by August 23, 2023. The trial was updated January 18, 2020 and is currently recruiting.
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Membros Artificiais , Lateralidade Funcional/fisiologia , Córtex Motor/fisiologia , Córtex Motor/fisiopatologia , Destreza Motora/fisiologia , Deformidades Congênitas das Extremidades Superiores/fisiopatologia , Criança , Feminino , Humanos , MasculinoRESUMO
Low-frequency vibrations coupled to high-frequency modes are known to influence the hydrogen bond strengths in a weakly interacting dimer. In this context, various acetic acid and acetamide dimers were analyzed using Møller-Plesset second-order perturbation (MP2) and density functional theory (DFT)-based approaches with explicit anharmonicity corrections. The computed low-frequency fundamentals as well as the high-frequency modes, which were found to be related to hydrogen bonding (OH/NH stretching modes), were analyzed and their computed intensities were correlated with their hydrogen-bond strengths/binding energies. There are similarities in the nature of eight low-frequency fundamentals of these two dimers, and the in-plane bending and stretch-bend fundamentals of the different dimers of these two species (in this low-frequency region) have specific roles in their relative stability order. The computed linear correlations were further verified against the results from coupled cluster calculations including triple excitation (CCSD(T)), Gaussian-G4 (G4), Gaussian-G2-MP2 (G2MP2) and complete basis set (CBS-QB3) methods of high accuracy energy calculations. As a consequence of such linear correlations, an additive property of local fragment energies (responsible for hydrogen bonding) was found to be a valid approximation to predict the binding energies of such dimers and the idea was found to be extendable to the other homologues of these acids/amides.
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Vibrational spectra are measured for Fe3+(CH4)n (n = 1-3) and Fe4+(CH4)4 in the C-H stretching region (2650-3100 cm-1) using photofragment spectroscopy, monitoring loss of CH4. All of the spectra are dominated by an intense peak at around 2800 cm-1 that is red-shifted by â¼120 cm-1 from free methane. This peak is due to the symmetric C-H stretch of the η3 hydrogen-coordinated methane ligands. For clusters with three iron atoms, the peak becomes less red-shifted as the number of methane ligands increases. For clusters with one methane ligand per iron atom, the red shift increases in going from Fe2+(CH4)2 (88 cm-1) to Fe3+(CH4)3 (108 cm-1) to Fe4+(CH4)4 (122 cm-1). This indicates increased covalency in the binding of methane to the larger iron clusters and parallels their increased reactivity. Density functional theory calculations, B3LYP, BPW91, and M11L, are used to identify possible structures and geometries and to predict the spectra. Results show that all three functionals tend to overestimate the methane binding energies. The M11L calculations provide the best match to the experimental spectra.
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Vibrational spectra are measured for Fe2(+)(CH4)n (n = 1-3) in the C-H stretching region (2650-3100 cm(-1)) using photofragment spectroscopy, by monitoring the loss of CH4. All of the spectra exhibit an intense peak corresponding to the symmetric C-H stretch around 2800 cm(-1). The presence of a single peak suggests a nearly equivalent interaction between the iron dimer and the methane ligands. The peak becomes slightly blue shifted as the number of methane ligands increases. Density functional theory calculations, B3LYP and BPW91, are used to identify possible structures and predict the spectra. Results suggest that the methane(s) bind in a terminal configuration and the complexes are in the octet spin state.
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The electronic spectra of Mn(+)(H2O) and Mn(+)(D2O) have been measured from 30,000 to 35,000 cm(-1) using photodissociation spectroscopy. Transitions are observed from the (7)A1 ground state in which the Mn(+) is in a 3d(5)4s(1) electronic configuration, to the (7)B2 (3d(5)4py) and (7)B1 (3d(5)4px) excited states with T0 = 30,210 and 32,274 cm(-1), respectively. Each electronic transition has partially resolved rotational and extensive vibrational structure with an extended progression in the metal-ligand stretch at a frequency of â¼450 cm(-1). There are also progressions in the in-plane bend in the (7)B2 state, due to vibronic coupling, and the out-of-plane bend in the (7)B1 state, where the calculation illustrates that this state is slightly non-planar. Electronic structure computations at the CCSD(T)/aug-cc-pVTZ and TD-DFT B3LYP/6-311++G(3df,3pd) level are also used to characterize the ground and excited states, respectively. These calculations predict a ground state Mn-O bond length of 2.18 Å. Analysis of the experimentally observed vibrational intensities reveals that this bond length decreases by 0.15 ± 0.015 Å and 0.14 ± 0.01 Å in the excited states. The behavior is accounted for by the less repulsive px and py orbitals causing the Mn(+) to interact more strongly with water in the excited states than the ground state. The result is a decrease in the Mn-O bond length, along with an increase in the H-O-H angle. The spectra have well resolved K rotational structure. Fitting this structure gives spin-rotation constants Éaaâ³ = -3 ± 1 cm(-1) for the ground state and Éaa' = 0.5 ± 0.5 cm(-1) and εaa' = -4.2 ± 0.7 cm(-1) for the first and second excited states, respectively, and A' = 12.8 ± 0.7 cm(-1) for the first excited state. Vibrationally mediated photodissociation studies determine the O-H antisymmetric stretching frequency in the ground electronic state to be 3658 cm(-1).
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Técnicas de Química Analítica/métodos , Óxido de Deutério/química , Manganês/química , Análise Espectral , Raios Ultravioleta , Água , Luz , Água/químicaRESUMO
BACKGROUND: The recent increase in the incidence of alcohol-associated hepatitis (AH) coincides with the obesity epidemic in the United States. However, current mouse models do not fully replicate the combined insults of obesity, metabolic dysfunction-associated steatohepatitis, and alcohol. The aim of this study was to develop a new mouse model that recapitulates the robust inflammatory and fibrotic phenotype characteristic of human MetALD. METHODS: Eight- to 10-week-old male C57BL/6 mice were fed chow or high fat-cholesterol-sugar diet (metabolic dysfunction-associated steatohepatitis diet) and in each group, some received alcohol in drinking water (ad libitum) and weekly alcohol binges (EtOH) for 3 months. The liver was assessed for features of AH. RESULTS: MetALD mice displayed increased liver damage indicated by highly elevated ALT and bilirubin levels compared to all other groups. Liver steatosis was significantly greater in the MetALD mice compared to all other experimental groups. The inflammatory phenotype of MetALD was also recapitulated, including increased IL-6 and IL-1ß protein levels as well as increased CD68+ macrophages and Ly6G+ neutrophils in the liver. Sirius red staining and expression of collagen 1, alpha-smooth muscle actin indicated advanced fibrosis in the livers of MetALD mice. In addition, indicators of epithelial-to-mesenchymal transition markers were increased in MetALD mice compared to all other groups. Furthermore, we found increased ductular reaction, dysregulated hedgehog signaling, and decreased liver synthetic functions, consistent with severe AH. CONCLUSIONS: Alcohol administration in mice combined with metabolic dysfunction-associated steatohepatitis diet recapitulates key characteristics of human AH including liver damage, steatosis, robust systemic inflammation, and liver immune cell infiltration. This model results in advanced liver fibrosis, ductular reaction, decreased synthetic function, and hepatocyte dedifferentiation, suggesting a robust model of MetALD in mice.
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Modelos Animais de Doenças , Hepatite Alcoólica , Camundongos Endogâmicos C57BL , Animais , Masculino , Camundongos , Hepatite Alcoólica/patologia , Dieta Hiperlipídica/efeitos adversos , Fígado/patologia , Fígado/metabolismo , Etanol/efeitos adversosRESUMO
Paediatrics with congenital upper-limb reduction deficiency often face difficulties with normal development such as motor skills, needing assistance with daily activities such as self-care limitations with certain movements, sports, or activities. The purpose of this non-randomized longitudinal controlled trial was to assess, using intent-to-treat analysis, the effects of an 8-week home intervention of prosthetic use on the sensorimotor cortex in paediatrics with congenital upper-limb reduction deficiency. A paediatric population with congenital upper-limb reduction deficiency (n = 14) who were aged 6-18 years and who had a 20° or greater range of motion in the appropriate joint of the affected arm to move the body-powered prosthesis were enrolled. An age- and sex-matched control group (n = 14) was also enrolled. Participants were non-randomized and fitted with a custom low-cost 3D printed prosthesis and participated in 8 weeks of prosthetic use training at home. Control participants utilized a prosthetic simulator. The home intervention incorporated daily use training and exercises utilizing the prosthesis in direct use and assistive tasks explained by the researchers. After the home intervention, both groups displayed significant improvements in gross manual dexterity. During prosthetic use with the affected limb, significant increases in oxygenated hemodynamic responses were only displayed in the left premotor cortex of the upper-limb reduction deficiency group. The novel findings of this non-randomized longitudinal controlled trial suggest that the intervention may have improved the functional role of the left hemisphere which translated to the improvement of learning direction during adaptation to visuomotor control. The prosthetic home intervention was assumed to provide closed-loop training which could provide a direct benefit to the motor development of paediatrics with upper-limb reduction deficiency.
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Severe alcohol-associated hepatitis (AH) is a life-threatening form of alcohol-associated liver disease. Liver neutrophil infiltration is a hallmark of AH, yet the effects of alcohol on neutrophil functions remain elusive. Identifying therapeutic targets to reduce neutrophil-mediated liver damage is essential. Bruton's tyrosine kinase (BTK) plays an important role in neutrophil development and function; however, the role of BTK in AH is unknown. Using RNA sequencing of circulating neutrophils, we found an increase in Btk expression (P = 0.05) and phosphorylated BTK (pBTK) in patients with AH compared with healthy controls. In vitro, physiologically relevant doses of alcohol resulted in a rapid, TLR4-mediated induction of pBTK in neutrophils. In a preclinical model of AH, administration of a small-molecule BTK inhibitor (evobrutinib) or myeloid-specific Btk knockout decreased proinflammatory cytokines and attenuated neutrophil-mediated liver damage. We found that pBTK was essential for alcohol-induced bone marrow granulopoiesis and liver neutrophil infiltration. In vivo, BTK inhibition or myeloid-specific Btk knockout reduced granulopoiesis, circulating neutrophils, liver neutrophil infiltration, and liver damage in a mouse model of AH. Mechanistically, using liquid chromatography-tandem mass spectrometry, we identified CD84 as a kinase target of BTK, which is involved in granulopoiesis. In vitro, CD84 promoted alcohol-induced interleukin-1ß and tumor necrosis factor-α in primary human neutrophils, which was inhibited by CD84-blocking antibody treatment. Our findings define the role of BTK and CD84 in regulating neutrophil inflammation and granulopoiesis, with potential therapeutic implications in AH.
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Tirosina Quinase da Agamaglobulinemia , Hepatopatias Alcoólicas , Neutrófilos , Tirosina Quinase da Agamaglobulinemia/metabolismo , Tirosina Quinase da Agamaglobulinemia/antagonistas & inibidores , Animais , Humanos , Neutrófilos/metabolismo , Neutrófilos/efeitos dos fármacos , Hepatopatias Alcoólicas/metabolismo , Hepatopatias Alcoólicas/patologia , Inibidores de Proteínas Quinases/farmacologia , Camundongos , Masculino , Fígado/patologia , Fígado/metabolismo , Fígado/efeitos dos fármacos , Granulócitos/metabolismo , Granulócitos/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Antígenos CD/metabolismo , Camundongos Knockout , Receptor 4 Toll-Like/metabolismo , Fosforilação/efeitos dos fármacosRESUMO
The main objective of this study was to describe the cortical patterns of brain activity during a gross dexterity task and develop a behavioral profile of children experiencing isolation. A cross-sectional assessment was conducted during one visit. Sample: Four pediatric patients who had undergone isolation within a hospital comprised the full data collection. During the collection, participants completed the Box and Blocks Test of gross manual dexterity while undergoing imaging of the motor cortex using functional near-infrared spectroscopy. Participants also completed a Behavioral Assessment System for Children, Third Edition (BASC-3) self-report, which was analyzed along with a parent report to quantify their emotional and social behaviors. All participants displayed lower gross dexterity levels than normative data. Furthermore, three out of the four participants displayed ipsilateral dominance of the motor cortex during the dexterity task. Three of the participants displayed behavioral measures reported within clinically significant or at-risk scores. Clinically significant behavioral scores coupled with lower than expected manual dexterity values and ipsilateral hemispheric dominance indicate that neuroplastic changes can occur in populations undergoing hospitalized isolation. While the impacts of the treatments and isolation in this case cannot be separated, further studies should be conducted to understand these impacts of isolation.
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Introduction: A short-term immobilization of one hand affects musculoskeletal functions, and the associated brain network adapts to the alterations happening to the body due to injuries. It was hypothesized that the injury-associated temporary disuse of the upper limb would alter the functional interactions of the motor cortical processes and will produce long-term changes throughout the immobilization and post-immobilization period. Methods: The case participant (male, 12 years old, right arm immobilized for clavicle fracture) was scanned using optical imaging technology of fNIRS over immobilization and post-immobilization. Pre-task data was collected for 3â min for RSFC analysis, processed, and analyzed using the Brain AnalyzIR toolbox. Connectivity was measured using Pearson correlation coefficients (R) from NIRS Toolbox's connectivity module. Results: The non-affected hand task presented an increased ipsilateral response during the immobilization period, which then decreased over the follow-up visits. The right-hand task showed a bilateral activation pattern following immobilization, but the contralateral activation pattern was restored during the 1-year follow-up visit. Significant differences in the average connection strength over the study period were observed. The average Connection strength decreased from the third week of immobilization and continued to be lower than the baseline value. Global network efficiency decreased in weeks two and three, while the network settled into a higher efficient state during the follow-up periods after post-immobilization. Discussion: Short-term immobilization of the upper limb is shown to have cortical changes in terms of activations of brain regions as well as connectivity. The short-term dis-use of the upper limb has shifted the unilateral activation pattern to the bilateral coactivation of the motor cortex from both hemispheres. Resting-state data reveals a disruption in the motor cortical network during the immobilization phase, and the network is reorganized into an efficient network over 1 year after the injury. Understanding such cortical reorganization could be informative for studying the recovery from neurological disorders affecting motor control in the future.
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Targeted muscle reinnervation (TMR) surgery involves the coaptation of amputated nerves to nearby motor nerve branches with the purpose of reclosing the neuromuscular loop in order to reduce phantom limb pain. The purpose of this case study was to create a phantom limb therapy protocol for an amputee after undergoing TMR surgery, where the four main nerves of his right arm were reinnervated into the chest muscles. The goal of this phantom limb therapy was to further strengthen these newly formed neuromuscular closed loops. The case participant (male, 21- years of age, height = 5'8â³ and weight = 134 lbs) presented 1- year after a trans-humeral amputation of the right arm along with TMR surgery and participated in phantom limb therapy for 3 months. Data collections for the subject occurred every 2 weeks for 3 months. During the data collections, the subject performed various movements of the phantom and intact limb specific to each reinnervated nerve and a gross manual dexterity task (Box and Block Test) while measuring brain activity and recording qualitative feedback from the subject. The results demonstrated that phantom limb therapy produced significant changes of cortical activity, reduced fatigue, fluctuation in phantom pain, improved limb synchronization, increased sensory sensation, and decreased correlation strength between intra-hemispheric and inter-hemispheric channels. These results suggest an overall improved cortical efficiency of the sensorimotor network. These results add to the growing knowledge of cortical reorganization after TMR surgery, which is becoming more common to aid in the recovery after amputation. More importantly, the results of this study suggest that the phantom limb therapy may have accelerated the decoupling process, which provides direct clinical benefits to the patient such as reduced fatigue and improved limb synchronization.
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Cancer immunotherapies, in particular checkpoint blockade immunotherapy (CBT), can induce control of cancer growth, with a fraction of patients experiencing durable responses. However, the majority of patients currently do not respond to CBT and the molecular determinants of resistance have not been fully elucidated. Mounting clinical evidence suggests that the clonal status of neoantigens (NeoAg) impacts the anti-tumor T cell response. High intratumor heterogeneity (ITH), where the majority of NeoAgs are expressed subclonally, is correlated with poor clinical response to CBT and poor infiltration with tumor-reactive T cells. However, the mechanism by which ITH blunts tumor-reactive T cells is unclear. We developed a transplantable murine lung cancer model to characterize the immune response against a defined set of NeoAgs expressed either clonally or subclonally to model low or high ITH, respectively. Here we show that clonal expression of a weakly immunogenic NeoAg with a relatively strong NeoAg increased the immunogenicity of tumors with low but not high ITH. Mechanistically we determined that clonal NeoAg expression allowed cross-presenting dendritic cells to acquire and present both NeoAgs. Dual NeoAg presentation by dendritic cells was associated with a more mature DC phenotype and a higher stimulatory capacity. These data suggest that clonal NeoAg expression can induce more potent anti-tumor responses due to more stimulatory dendritic cell:T cell interactions. Therapeutic vaccination targeting subclonally expressed NeoAgs could be used to boost anti-tumor T cell responses.
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Apresentação Cruzada , Neoplasias Pulmonares , Animais , Camundongos , Antígenos de Neoplasias/genética , Neoplasias Pulmonares/genética , Linfócitos T , Células DendríticasRESUMO
OBJECTIVE: Attention, inhibition, and processing speed are related to functional decline among older adults. This study attempts to clarify the relationships between these cognitive factors and adaptive functioning. METHOD: We examined relationships between attention, inhibition, and processing speed, with scores on the Texas Functional Living Scale (TFLS), a performance-based measure of daily functioning, in a mixed clinical sample of 530 older adults who were referred for an outpatient neuropsychological evaluation. RESULTS: The current study used a confirmatory factor analysis (CFA) to derive a three-factor cognitive model consisting of attention, inhibition, and processing speed. Results from a hierarchical regression, which included factor scores from the CFA, revealed that processing speed was the only significant predictor of TFLS performance when all three cognitive factors were included within a single model. CONCLUSION: These results highlight the influence of processing speed as an important indicator of functional decline among a clinical population of older adults.
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Atividades Cotidianas , Cognição , Humanos , Idoso , Testes Neuropsicológicos , Atividades Cotidianas/psicologia , Texas , Cognição/fisiologia , AtençãoRESUMO
Massive inflammation and liver failure are main contributors to the high mortality in alcohol-associated hepatitis (AH). In recent clinical trials, granulocyte colony-stimulating factor (G-CSF) therapy improved liver function and survival in patients with AH. However, the mechanisms of G-CSF-mediated beneficial effects in AH remain elusive. In this study, we evaluated effects of in vivo G-CSF administration, using a mouse model of AH. G-CSF treatment significantly reduced liver damage in alcohol-fed mice even though it increased the numbers of liver-infiltrating immune cells, including neutrophils and inflammatory monocytes. Moreover, G-CSF promoted macrophage polarization toward an M2-like phenotype and increased hepatocyte proliferation, which was indicated by an increased Ki67-positive signal colocalized with hepatocyte nuclear factor 4 alpha (HNF-4α) and cyclin D1 expression in hepatocytes. We found that G-CSF increased G-CSF receptor expression and resulted in reduced levels of phosphorylated ß-catenin in hepatocytes. In the presence of an additional pathogen-associated molecule, lipopolysaccharide (LPS), which is significantly increased in the circulation and liver of patients with AH, the G-CSF-induced hepatoprotective effects were abolished in alcohol-fed mice. We still observed increased Ki67-positive signals in alcohol-fed mice following G-CSF treatment; however, Ki67 and HNF-4α did not colocalize in LPS-challenged mice. Conclusion: G-CSF treatment increases immune cell populations, particularly neutrophil counts, and promotes M2-like macrophage differentiation in the liver. More importantly, G-CSF treatment reduces alcohol-induced liver injury and promotes hepatocyte proliferation in alcohol-fed mice. These data provide new insights into the understanding of mechanisms mediated by G-CSF and its therapeutic effects in AH.
Assuntos
Hepatite Alcoólica , Proliferação de Células , Etanol/metabolismo , Fator Estimulador de Colônias de Granulócitos/farmacologia , Hepatite Alcoólica/tratamento farmacológico , Hepatócitos , Humanos , Antígeno Ki-67/metabolismo , Lipopolissacarídeos/metabolismo , MacrófagosRESUMO
This study aimed to examine the neural responses of children using prostheses and prosthetic simulators to better elucidate the emulation abilities of the simulators. We utilized functional near-infrared spectroscopy (fNIRS) to evaluate the neural response in five children with a congenital upper limb reduction (ULR) using a body-powered prosthesis to complete a 60 s gross motor dexterity task. The ULR group was matched with five typically developing children (TD) using their non-preferred hand and a prosthetic simulator on the same hand. The ULR group had lower activation within the primary motor cortex (M1) and supplementary motor area (SMA) compared to the TD group, but nonsignificant differences in the primary somatosensory area (S1). Compared to using their non-preferred hand, the TD group exhibited significantly higher action in S1 when using the simulator, but nonsignificant differences in M1 and SMA. The non-significant differences in S1 activation between groups and the increased activation evoked by the simulator's use may suggest rapid changes in feedback prioritization during tool use. We suggest that prosthetic simulators may elicit increased reliance on proprioceptive and tactile feedback during motor tasks. This knowledge may help to develop future prosthesis rehabilitative training or the improvement of tool-based skills.