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1.
Cell ; 178(1): 176-189.e15, 2019 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-31155231

RESUMO

RLR-mediated type I IFN production plays a pivotal role in elevating host immunity for viral clearance and cancer immune surveillance. Here, we report that glycolysis, which is inactivated during RLR activation, serves as a barrier to impede type I IFN production upon RLR activation. RLR-triggered MAVS-RIG-I recognition hijacks hexokinase binding to MAVS, leading to the impairment of hexokinase mitochondria localization and activation. Lactate serves as a key metabolite responsible for glycolysis-mediated RLR signaling inhibition by directly binding to MAVS transmembrane (TM) domain and preventing MAVS aggregation. Notably, lactate restoration reverses increased IFN production caused by lactate deficiency. Using pharmacological and genetic approaches, we show that lactate reduction by lactate dehydrogenase A (LDHA) inactivation heightens type I IFN production to protect mice from viral infection. Our study establishes a critical role of glycolysis-derived lactate in limiting RLR signaling and identifies MAVS as a direct sensor of lactate, which functions to connect energy metabolism and innate immunity.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteína DEAD-box 58/antagonistas & inibidores , Proteína DEAD-box 58/metabolismo , Ácido Láctico/farmacologia , Receptores de Superfície Celular/antagonistas & inibidores , Receptores de Superfície Celular/metabolismo , Animais , Feminino , Glicólise , Células HEK293 , Humanos , Interferon beta/metabolismo , L-Lactato Desidrogenase/genética , L-Lactato Desidrogenase/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Células RAW 264.7 , Receptores Imunológicos , Transdução de Sinais/efeitos dos fármacos , Transfecção
2.
Immunity ; 57(1): 106-123.e7, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38159573

RESUMO

When the filtrate of the glomerulus flows through the renal tubular system, various microscopic sediment particles, including mineral crystals, are generated. Dislodging these particles is critical to ensuring the free flow of filtrate, whereas failure to remove them will result in kidney stone formation and obstruction. However, the underlying mechanism for the clearance is unclear. Here, using high-resolution microscopy, we found that the juxtatubular macrophages in the renal medulla constitutively formed transepithelial protrusions and "sampled" urine contents. They efficiently sequestered and phagocytosed intraluminal sediment particles and occasionally transmigrated to the tubule lumen to escort the excretion of urine particles. Mice with decreased renal macrophage numbers were prone to developing various intratubular sediments, including kidney stones. Mechanistically, the transepithelial behaviors of medulla macrophages required integrin ß1-mediated ligation to the tubular epithelium. These findings indicate that medulla macrophages sample urine content and remove intratubular particles to keep the tubular system unobstructed.


Assuntos
Cálculos Renais , Rim , Camundongos , Animais , Macrófagos
3.
Mol Cell ; 80(2): 263-278.e7, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-33022274

RESUMO

Cancer metastasis accounts for the major cause of cancer-related deaths. How disseminated cancer cells cope with hostile microenvironments in secondary site for full-blown metastasis is largely unknown. Here, we show that AMPK (AMP-activated protein kinase), activated in mouse metastasis models, drives pyruvate dehydrogenase complex (PDHc) activation to maintain TCA cycle (tricarboxylic acid cycle) and promotes cancer metastasis by adapting cancer cells to metabolic and oxidative stresses. This AMPK-PDHc axis is activated in advanced breast cancer and predicts poor metastasis-free survival. Mechanistically, AMPK localizes in the mitochondrial matrix and phosphorylates the catalytic alpha subunit of PDHc (PDHA) on two residues S295 and S314, which activates the enzymatic activity of PDHc and alleviates an inhibitory phosphorylation by PDHKs, respectively. Importantly, these phosphorylation events mediate PDHc function in cancer metastasis. Our study reveals that AMPK-mediated PDHA phosphorylation drives PDHc activation and TCA cycle to empower cancer cells adaptation to metastatic microenvironments for metastasis.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Ciclo do Ácido Cítrico , Complexo Piruvato Desidrogenase/metabolismo , Animais , Domínio Catalítico , Linhagem Celular Tumoral , Sobrevivência Celular , Ativação Enzimática , Feminino , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Metástase Neoplásica , Fosforilação , Fosfosserina/metabolismo , Transdução de Sinais , Estresse Fisiológico , Análise de Sobrevida
4.
Nature ; 597(7874): 57-63, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34471277

RESUMO

Fibre lithium-ion batteries are attractive as flexible power solutions because they can be woven into textiles, offering a convenient way to power future wearable electronics1-4. However, they are difficult to produce in lengths of more than a few centimetres, and longer fibres were thought to have higher internal resistances3,5 that compromised electrochemical performance6,7. Here we show that the internal resistance of such fibres has a hyperbolic cotangent function relationship with fibre length, where it first decreases before levelling off as length increases. Systematic studies confirm that this unexpected result is true for different fibre batteries. We are able to produce metres of high-performing fibre lithium-ion batteries through an optimized scalable industrial process. Our mass-produced fibre batteries have an energy density of 85.69 watt hour per kilogram (typical values8 are less than 1 watt hour per kilogram), based on the total weight of a lithium cobalt oxide/graphite full battery, including packaging. Its capacity retention reaches 90.5% after 500 charge-discharge cycles and 93% at 1C rate (compared with 0.1C rate capacity), which is comparable to commercial batteries such as pouch cells. Over 80 per cent capacity can be maintained after bending the fibre for 100,000 cycles. We show that fibre lithium-ion batteries woven into safe and washable textiles by industrial rapier loom can wirelessly charge a cell phone or power a health management jacket integrated with fibre sensors and a textile display.


Assuntos
Cobalto/química , Fontes de Energia Elétrica , Eletrônica , Lítio/química , Óxidos/química , Têxteis , Dispositivos Eletrônicos Vestíveis , Grafite/química , Humanos , Íons , Masculino , Tecnologia sem Fio
5.
Proc Natl Acad Sci U S A ; 119(39): e2211234119, 2022 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-36122246

RESUMO

Whether or not nonavian dinosaur biodiversity declined prior to the end-Cretaceous mass extinction remains controversial as the result of sampling biases in the fossil record, differences in the analytical approaches used, and the rarity of high-precision geochronological dating of dinosaur fossils. Using magnetostratigraphy, cyclostratigraphy, and biostratigraphy, we establish a high-resolution geochronological framework for the fossil-rich Late Cretaceous sedimentary sequence in the Shanyang Basin of central China. We have found only three dinosaurian eggshell taxa (Macroolithus yaotunensis, Elongatoolithus elongatus, and Stromatoolithus pinglingensis) representing two clades (Oviraptoridae and Hadrosauridae) in sediments deposited between ∼68.2 and ∼66.4 million y ago, indicating sustained low dinosaur biodiversity, and that assessment is consistent with the known skeletal remains in the Shanyang and surrounding basins of central China. Along with the dinosaur eggshell records from eastern and southern China, we find a decline in dinosaur biodiversity from the Campanian to the Maastrichtian. Our results support a long-term decline in global dinosaur biodiversity prior to 66 million y ago, which likely set the stage for the end-Cretaceous nonavian dinosaur mass extinction.


Assuntos
Biodiversidade , Dinossauros , Extinção Biológica , Fósseis , Animais , China , Dinossauros/classificação
6.
Stroke ; 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39114924

RESUMO

BACKGROUND: Cerebral small vessel disease (CSVD) is a group of neurological disorders that affect the small blood vessels within the brain, for which no effective treatments are currently available. We conducted a Mendelian randomization (MR) study to identify candidate therapeutic genes for CSVD. METHODS: We retrieved genome-wide association study data from 6 recently conducted, extensive investigations focusing on CSVD magnetic resonance imaging markers and performed a 2-sample MR analysis to assess the potential causal effects of gene expression and protein level within druggable genes on CSVD in blood and brain tissues. Colocalization analyses and repeat studies were undertaken to verify the relationship. Additionally, mediation analysis was conducted to explore the potential mechanisms involving druggable genes and known risk factors for CSVD. Finally, phenome-wide MR analyses were applied to evaluate the potential adverse effects related to the identified druggable genes for CSVD treatment. RESULTS: Overall, 5 druggable genes consistently showed associations with CSVD in MR analyses across both the discovery and validation cohorts. Notably, the ALDH2 and KLHL24 genes were identified as associated with CSVD in both blood and brain tissues, whereas the genes ADRB1, BTN3A2, and EFEMP1 were exclusively detected in brain tissue. Moreover, mediation analysis elucidated the proportion of the total effects mediated by CSVD risk factors through candidate druggable genes, which ranged from 5.5% to 18.5%, and offered potential explanations for the observed results. A comprehensive phenome-wide MR analysis further emphasized both the therapeutic benefits and potential side effects of targeting these candidate druggable genes. CONCLUSIONS: This study provides genetic evidence supporting the potential therapeutic benefits of targeting druggable genes for treating CSVD, which will be useful for prioritizing CSVD drug development.

7.
Kidney Int ; 105(4): 759-774, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38296028

RESUMO

Lupus nephritis (LN) is one of the most severe manifestations of systemic lupus erythematosus (SLE), but its mechanism of onset remains unclear. Since impaired mitophagy has been implicated in multiple organs in SLE, we hypothesized that mitophagy dysfunction is critical in the development of LN and that pharmacologically targeting mitophagy would ameliorate this disease. Therefore, lupus-prone MRL/MpJ-Faslpr (MRL/lpr) and NZBWF1/J mice were treated with a novel mitophagy inducer, UMI-77, during their onset of LN. This treatment effectively mitigated kidney inflammation and damage as assessed by histology and flow cytometry. Furthermore, dendritic cell (DC)-T-cell coculture assay indicated that UMI-77 treatment attenuated DC function that would drive T-cell proliferation but did not directly influence the potent T-cell proliferation in lupus mice. UMI-77 also restored mitochondrial function and attenuated proinflammatory phenotypes in lupus DCs. Adoptive transfer of DCs from MRL/lpr mice augmented serum anti-dsDNA IgG, urine protein and T-cell infiltration of the kidney in MRL/MpJ mice, which could be prevented by either treating lupus donors in vivo or lupus DCs directly with UMI-77. UMI-77 also restored mitochondrial function in myeloid cells from patients with LN in vitro as evidenced by increased ATP levels. Thus, enhancing mitophagy in SLE restrains autoimmunity and limits kidney inflammation for LN development. Hence, our findings suggest targeting mitophagy as a tangible pathway to treat LN.


Assuntos
Lúpus Eritematoso Sistêmico , Nefrite Lúpica , Sulfonamidas , Tioglicolatos , Humanos , Camundongos , Animais , Nefrite Lúpica/patologia , Autoantígenos , Mitofagia , Camundongos Endogâmicos MRL lpr , Rim/patologia , Células Mieloides , Inflamação/patologia
8.
Clin Immunol ; 261: 109941, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38365047

RESUMO

Chronic rejection is the primary cause of late allograft failure, however, the current treatments for chronic rejection have not yielded desirable therapeutic effects. B cell activation and donor-specific antibody (DSA) production are the primary factors leading to chronic rejection. Bruton's tyrosine kinase (BTK) plays a key role in the activation and differentiation of B cells and in antibody production. This study investigated the efficacy of blocking BTK signalling in the prevention of chronic rejection. BTK signalling was blocked using the BTK inhibitor ibrutinib and gene knockout. In vitro assays were conducted to examine the consequences and underlying mechanisms of BTK blockade in regards to B cell activation, differentiation, and antibody secretion. Additionally, we established a cardiac transplantation mouse model of chronic rejection to explore the preventive effects and mechanisms of BTK ablation on chronic rejection. Ablating BTK signalling in vitro resulted in the inhibition of B cell activation, differentiation, and antibody production. In vivo experiments provided evidence that ablating BTK signalling alleviated chronic rejection, leading to reduced damage in myocardial tissue, neointimal hyperplasia, interstitial fibrosis, inflammatory cell infiltration, and C4d deposition. Allograft survival was prolonged, and B cell responses and DSA production were inhibited as a result. We confirmed that ablation of BTK signalling inhibited B cell response by blocking downstream PLCγ2 phosphorylation and inhibiting the NF-κB, NFAT, and ERK pathways. Our findings demonstrated that ablation of BTK signalling inhibited B cell activation and differentiation, reduced DSA production, and effectively prevented chronic rejection.


Assuntos
Formação de Anticorpos , Transplante de Coração , Animais , Camundongos , Tirosina Quinase da Agamaglobulinemia , Linfócitos B , Transdução de Sinais
9.
Hum Brain Mapp ; 45(11): e26790, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39037119

RESUMO

Brain glymphatic dysfunction is critical in neurodegenerative processes. While animal studies have provided substantial insights, understandings in humans remains limited. Recent attention has focused on the non-invasive evaluation of brain glymphatic function. However, its association with brain parenchymal lesions in large-scale population remains under-investigated. In this cross-sectional analysis of 1030 participants (57.14 ± 9.34 years, 37.18% males) from the Shunyi cohort, we developed an automated pipeline to calculate diffusion-weighted image analysis along the perivascular space (ALPS), with a lower ALPS value indicating worse glymphatic function. The automated ALPS showed high consistency with the manual calculation of this index (ICC = 0.81, 95% CI: 0.662-0.898). We found that those with older age and male sex had lower automated ALPS values (ß = -0.051, SE = 0.004, p < .001, per 10 years, and ß = -0.036, SE = 0.008, p < .001, respectively). White matter hyperintensity (ß = -2.458, SE = 0.175, p < .001) and presence of lacunes (OR = 0.004, 95% CI < 0.002-0.016, p < .001) were significantly correlated with decreased ALPS. The brain parenchymal and hippocampal fractions were significantly associated with decreased ALPS (ß = 0.067, SE = 0.007, p < .001 and ß = 0.040, SE = 0.014, p = .006, respectively) independent of white matter hyperintensity. Our research implies that the automated ALPS index is potentially a valuable imaging marker for the glymphatic system, deepening our understanding of glymphatic dysfunction.


Assuntos
Imagem de Difusão por Ressonância Magnética , Sistema Glinfático , Humanos , Masculino , Feminino , Sistema Glinfático/diagnóstico por imagem , Sistema Glinfático/patologia , Sistema Glinfático/fisiopatologia , Pessoa de Meia-Idade , Estudos Transversais , Idoso , Imagem de Difusão por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Processamento de Imagem Assistida por Computador/métodos , Adulto , Estudos de Coortes
10.
Small ; : e2401334, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38804884

RESUMO

Lung cancer, a highly prevalent and lethal form of cancer, is often associated with oxidative stress. Photodynamic therapy (PDT) has emerged as a promising alternative therapeutic tool in cancer treatments, but its efficacy is closely correlated to the photosensitizers generating reactive oxygen species (ROS) and the antioxidant capacity of tumor cells. In particular, glutathione (GSH) can reduce the ROS and thus compromise PDT efficacy. In this study, a GSH-responsive near-infrared photosensitizer (TBPPN) based on aggregation-induced emission for real-time monitoring of GSH levels and enhanced PDT for lung cancer treatment is developed. The strategic design of TBPPN, consisting of a donor-acceptor structure and incorporation of dinitrobenzene, enables dual functionality by not only the fluorescence being activated by GSH but also depleting GSH to enhance the cytotoxic effect of PDT. TBPPN demonstrates synergistic PDT efficacy in vitro against A549 lung cancer cells by specifically targeting different cellular compartments and depleting intracellular GSH. In vivo studies further confirm that TBPPN can effectively inhibit tumor growth in a mouse model with lung cancer, highlighting its potential as an integrated agent for the diagnosis and treatment of lung cancer. This approach enhances the effectiveness of PDT for lung cancer and deserves further exploration of its potential for clinical application.

11.
J Transl Med ; 22(1): 465, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38755664

RESUMO

Disturbance in mitochondrial homeostasis within proximal tubules is a critical characteristic associated with diabetic kidney disease (DKD). CaMKKß/AMPK signaling plays an important role in regulating mitochondrial homeostasis. Despite the downregulation of CaMKKß in DKD pathology, the underlying mechanism remains elusive. The expression of NEDD4L, which is primarily localized to renal proximal tubules, is significantly upregulated in the renal tubules of mice with DKD. Coimmunoprecipitation (Co-IP) assays revealed a physical interaction between NEDD4L and CaMKKß. Moreover, deletion of NEDD4L under high glucose conditions prevented rapid CaMKKß protein degradation. In vitro studies revealed that the aberrant expression of NEDD4L negatively influences the protein stability of CaMKKß. This study also explored the role of NEDD4L in DKD by using AAV-shNedd4L in db/db mice. These findings confirmed that NEDD4L inhibition leads to a decrease in urine protein excretion, tubulointerstitial fibrosis, and oxidative stress, and mitochondrial dysfunction. Further in vitro studies demonstrated that si-Nedd4L suppressed mitochondrial fission and reactive oxygen species (ROS) production, effects antagonized by si-CaMKKß. In summary, the findings provided herein provide strong evidence that dysregulated NEDD4L disturbs mitochondrial homeostasis by negatively modulating CaMKKß in the context of DKD. This evidence underscores the potential of therapeutic interventions targeting NEDD4L and CaMKKß to safeguard renal tubular function in the management of DKD.


Assuntos
Quinase da Proteína Quinase Dependente de Cálcio-Calmodulina , Nefropatias Diabéticas , Regulação para Baixo , Homeostase , Mitocôndrias , Ubiquitina-Proteína Ligases Nedd4 , Animais , Humanos , Masculino , Camundongos , Quinase da Proteína Quinase Dependente de Cálcio-Calmodulina/metabolismo , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/patologia , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Dinâmica Mitocondrial , Ubiquitina-Proteína Ligases Nedd4/metabolismo , Ubiquitina-Proteína Ligases Nedd4/genética , Estresse Oxidativo , Estabilidade Proteica , Proteólise , Espécies Reativas de Oxigênio/metabolismo
12.
Magn Reson Med ; 92(5): 2091-2100, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39011598

RESUMO

PURPOSE: To mitigate the B0/B1 + sensitivity of velocity-selective inversion (VSI) pulse trains for velocity-selective arterial spin labeling (VSASL) by implementing adiabatic refocusing. This approach aims to achieve artifact-free VSI-based perfusion imaging through single-pair label-control subtractions, reducing the need for the currently required four-pair dynamic phase-cycling (DPC) technique when using a velocity-insensitive control. METHODS: We introduce a Fourier-transform VSI (FT-VSI) train that incorporates sinc-modulated hard excitation pulses with MLEV-8-modulated adiabatic hyperbolic secant refocusing pairs. We compare performance between this train and the standard composite refocusing train, including with and without DPC, for dual-module VSI VSASL. We evaluate (1) simulated velocity-selective profiles and subtraction fidelity across a broad B0/B1 + range, (2) subtraction fidelity in phantoms, and (3) image quality, artifact presence, and gray-matter perfusion heterogeneity (as measured by the spatial coefficient of variation) in healthy human subjects. RESULTS: Adiabatic refocusing significantly improves FT-VSI robustness to B0/B1 + inhomogeneity for a single label-control subtraction. Subtraction fidelity is dramatically improved in both simulation and phantoms compared with composite refocusing without DPC, and is similar compared with DPC methods. In humans, marked artifacts seen with the non-DPC composite refocusing approach are eliminated, corroborated by significantly reduced gray-matter heterogeneity (via lower spatial coefficient of variation values). CONCLUSION: A novel VSASL labeling train using adiabatic refocusing pulses for VSI was found to reduce artifacts related to B0/B1 + inhomogeneity, thereby providing an alternative to DPC and its associated limitations, which include increased vulnerability to physiological noise and motion, reduced functional MRI applicability, and suboptimal data censoring.


Assuntos
Algoritmos , Artefatos , Processamento de Imagem Assistida por Computador , Imagens de Fantasmas , Marcadores de Spin , Humanos , Processamento de Imagem Assistida por Computador/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/irrigação sanguínea , Adulto , Análise de Fourier , Masculino , Feminino , Circulação Cerebrovascular/fisiologia , Imageamento por Ressonância Magnética/métodos , Simulação por Computador , Angiografia por Ressonância Magnética/métodos , Substância Cinzenta/diagnóstico por imagem
13.
Magn Reson Med ; 92(3): 1149-1161, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38650444

RESUMO

PURPOSE: To improve image quality, mitigate quantification biases and variations for free-breathing liver proton density fat fraction (PDFF) and R 2 * $$ {\mathrm{R}}_2^{\ast } $$ quantification accelerated by radial k-space undersampling. METHODS: A free-breathing multi-echo stack-of-radial MRI method was developed with compressed sensing with multidimensional regularization. It was validated in motion phantoms with reference acquisitions without motion and in 11 subjects (6 patients with nonalcoholic fatty liver disease) with reference breath-hold Cartesian acquisitions. Images, PDFF, and R 2 * $$ {\mathrm{R}}_2^{\ast } $$ maps were reconstructed using different radial view k-space sampling factors and reconstruction settings. Results were compared with reference-standard results using Bland-Altman analysis. Using linear mixed-effects model fitting (p < 0.05 considered significant), mean and SD were evaluated for biases and variations of PDFF and R 2 * $$ {\mathrm{R}}_2^{\ast } $$ , respectively, and coefficient of variation on the first echo image was evaluated as a surrogate for image quality. RESULTS: Using the empirically determined optimal sampling factor of 0.25 in the accelerated in vivo protocols, mean differences and limits of agreement for the proposed method were [-0.5; -33.6, 32.7] s-1 for R 2 * $$ {\mathrm{R}}_2^{\ast } $$ and [-1.0%; -5.8%, 3.8%] for PDFF, close to those of a previous self-gating method using fully sampled radial views: [-0.1; -27.1, 27.0] s-1 for R 2 * $$ {\mathrm{R}}_2^{\ast } $$ and [-0.4%; -4.5%, 3.7%] for PDFF. The proposed method had significantly lower coefficient of variation than other methods (p < 0.001). Effective acquisition time of 64 s or 59 s was achieved, compared with 171 s or 153 s for two baseline protocols with different radial views corresponding to sampling factor of 1.0. CONCLUSION: This proposed method may allow accelerated free-breathing liver PDFF and R 2 * $$ {\mathrm{R}}_2^{\ast } $$ mapping with reduced biases and variations.


Assuntos
Processamento de Imagem Assistida por Computador , Fígado , Imageamento por Ressonância Magnética , Imagens de Fantasmas , Humanos , Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Estudos Retrospectivos , Feminino , Masculino , Processamento de Imagem Assistida por Computador/métodos , Pessoa de Meia-Idade , Respiração , Algoritmos , Adulto , Reprodutibilidade dos Testes , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Movimento (Física) , Tecido Adiposo/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Idoso
14.
Magn Reson Med ; 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39171431

RESUMO

PURPOSE: Radiotherapy treatment planning (RTP) using MR has been used increasingly for the abdominal site. Multiple contrast weightings and motion-resolved imaging are desired for accurate delineation of the target and various organs-at-risk and patient-tailored planning. Current MR protocols achieve these through multiple scans with distinct contrast and variable respiratory motion management strategies and acquisition parameters, leading to a complex and inaccurate planning process. This study presents a standalone MR Multitasking (MT)-based technique to produce volumetric, motion-resolved, multicontrast images for abdominal radiotherapy treatment planning. METHODS: The MT technique resolves motion and provides a wide range of contrast weightings by repeating a magnetization-prepared (saturation recovery and T2 preparations) spoiled gradient-echo readout series and adopting the MT image reconstruction framework. The performance of the technique was assessed through digital phantom simulations and in vivo studies of both healthy volunteers and patients with liver tumors. RESULTS: In the digital phantom study, the MT technique presented structural details and motion in excellent agreement with the digital ground truth. The in vivo studies showed that the motion range was highly correlated (R2 = 0.82) between MT and 2D cine imaging. MT allowed for a flexible contrast-weighting selection for better visualization. Initial clinical testing with interobserver analysis demonstrated acceptable target delineation quality (Dice coefficient = 0.85 ± 0.05, Hausdorff distance = 3.3 ± 0.72 mm). CONCLUSION: The developed MT-based, abdomen-dedicated technique is capable of providing motion-resolved, multicontrast volumetric images in a single scan, which may facilitate abdominal radiotherapy treatment planning.

15.
Med Care ; 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39103294

RESUMO

INTRODUCTION: Predictive models have proliferated in the health system in recent years and have been used to predict both health services utilization and medical outcomes. Less is known, however, on how these models function and how they might adapt to different contexts. The purpose of the current study is to shed light on the inner workings of a large-scale predictive model deployed in 2 distinct populations, with a particular emphasis on adaptability issues. METHODS: We compared the performance and functioning of a predictive model of avoidable hospitalization in 2 very different populations: Medicaid and Medicare enrollees in Maryland. Specifically, we assessed characteristics of the risk scores from March 2022 for the 2 populations, the predictive ability of the scores, and the driving risk factors behind the scores. In addition, we created and assessed the performance of an "unadapted" model by applying coefficients from the Medicare model to the Medicaid population. RESULTS: The model adapted to, and performed well in, both populations, despite demographic differences in these 2 groups. However, the most salient risk factors and their relative weightings differed, sometimes dramatically, across the 2 populations. The unadapted Medicaid model displayed poor performance relative to the adapted model. CONCLUSIONS: Our findings speak to the need to "peek behind the curtain" of predictive models that may be applied to different populations, and we caution that risk prediction is not "one size fits all": for optimal performance, models should be adapted to, and trained on, the target population.

16.
Mov Disord ; 39(3): 585-595, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38247265

RESUMO

BACKGROUND: Clinical trials of new drugs for tic disorders (TD) often fail to yield positive results. Placebo and nocebo responses play a vital role in interpreting the outcomes of randomized controlled trials (RCTs), yet these responses in RCTs of TD remain unexplored. OBJECTIVE: The aim was to assess the magnitude of placebo and nocebo responses in RCTs of pharmacological interventions for TD and identify influencing factors. METHODS: A systematic search of the Embase, Medline, Cochrane Central Register of Controlled Trials, and PsycINFO databases was conducted. Eligible studies were RCTs that compared active pharmacological agents with placebos. Placebo response was defined as the change from baseline in TD symptom severity in the placebo group, and nocebo response as the proportion experiencing adverse events (AEs) in this group. Subgroup analysis and meta-regression were performed to explore modifying factors. RESULTS: Twenty-four trials involving 2222 participants were included in this study. A substantial placebo response in TD symptom severity was identified, with a pooled effect size of -0.79 (95% confidence interval [CI] -0.99 to -0.59; I2 = 67%). Forty-four percent (95% CI 27% to 63%; I2 = 92%) of patients experienced AEs while taking inert pills. Sample size, study design, and randomization ratio were correlated with changes in placebo and nocebo responses. CONCLUSION: There were considerable placebo and nocebo responses in TD clinical trials. These results are of great relevance for the design of future trials and for clinical practice in TD. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration ID CRD42023388397. © 2024 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Efeito Nocebo , Efeito Placebo , Transtornos de Tique , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Transtornos de Tique/tratamento farmacológico
17.
Am J Nephrol ; 55(1): 25-36, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37963441

RESUMO

INTRODUCTION: Rituximab has been proven effective and safe in pediatric patients with frequently relapsing or steroid-dependent nephrotic syndrome (FR/SDNS). We aimed to analyze the efficacy and safety of rituximab in adult FR/SDNS patients with minimal change disease (MCD) and focal segmental glomerulosclerosis (FSGS). METHODS: A retrospective cohort study at three nephrology centers in China included adult FR/SDNS patients with biopsy-proven MCD or FSGS. Primary outcomes were relapse frequency and first relapse-free survival time. Adverse events were well recorded, and logistic regression analyses were used to investigate the risk factors of relapse. RESULTS: Eighty-one patients (age, 25.0 years; interquartile range, 20.0-40.5; 67% males; 82.7% MCD) received an average rituximab dose of 1,393.8 ± 618.7 mg/2 years during the 2-year follow-up period. The relapse frequency, calculated as the ratio of relapse times to follow-up years, significantly decreased after rituximab treatment (0.04 [0.00, 0.08] vs. 1.71 [1.00, 2.45], p < 0.001). The first relapse-free survival time was 16.7 ± 8.0 months. Fifty-seven patients (70.4%) achieved cessation of corticosteroids and immunosuppressants within 3 months after the first rituximab infusion. Adverse events were mostly mild, and no severe treatment-related adverse events were observed. Low serum albumin level before rituximab and high CD56+CD16+ natural killer cell count after rituximab were independent risk factors of relapse within 2 years after rituximab treatment. CONCLUSION: Rituximab was proven an effective and safe treatment option for adult FR/SDNS patients with MCD or FSGS in maintaining disease remission and minimizing corticosteroid exposure.


Assuntos
Glomerulosclerose Segmentar e Focal , Nefrose Lipoide , Síndrome Nefrótica , Masculino , Adulto , Humanos , Criança , Feminino , Rituximab/efeitos adversos , Glomerulosclerose Segmentar e Focal/complicações , Glomerulosclerose Segmentar e Focal/tratamento farmacológico , Estudos Retrospectivos , Síndrome Nefrótica/tratamento farmacológico , Síndrome Nefrótica/induzido quimicamente , Nefrose Lipoide/tratamento farmacológico , Nefrose Lipoide/induzido quimicamente , Imunossupressores/efeitos adversos , Recidiva , Doença Crônica , Resultado do Tratamento
18.
J Magn Reson Imaging ; 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39143805

RESUMO

BACKGROUND: The rotating Cartesian k-space multiphase steady-state imaging with contrast (ROCK-MUSIC) pulse sequence enables acquisition of whole-heart, cardiac phase-resolved images in pediatric congenital heart disease (CHD) without reliance on the ventilator gating signal. Multidimensional reconstruction with low rank tensor (LRT) has shown promise for resolving complex cardiorespiratory motion. PURPOSE: To enhance ROCK-MUSIC by resolving cardiorespiratory phases using LRT reconstruction and to enable semi-automatic hyperparameter tuning by developing an image quality scoring model. STUDY TYPE: Retrospective. POPULATION: Thirty patients (45% female, age 2 days to 6.7 years) with CHD. FIELD STRENGTH/SEQUENCE: 3-T, four-dimensional (4D) spoiled gradient recalled echo sequence. ASSESSMENT: Eigenvector-based iTerative Self-consistent Parallel Imaging Reconstruction (ESPIRiT) served as the reference comparison for LRT reconstruction. A 4-point Likert scale was used for cardiac and vascular image quality scoring based on cardiac chamber definition, lumen signal uniformity, vascular margin clarity, and motion artifact. Ejection fraction and ventricular volumes were assessed in 16 patients. Signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and edge sharpness were computed. STATISTICAL TESTS: Intraclass correlation coefficients, Wilcoxon signed-rank test, Bland-Altman. A P-value <0.05 was considered statistically significant. RESULTS: Relative to ESPIRiT, LRT images received significantly higher cardiac (2.81 ± 0.57 vs. 3.19 ± 0.54) and vascular (2.81 ± 0.60 vs. 3.36 ± 0.53) image quality scores. Image quality scoring with semi-automated hyperparameter tuning showed strong correlations (R2 = 0.748) among image quality, SNR, and septal sharpness. Comparison of ejection fraction and volumetry derived from ESPIRiT, and LRT showed no significant systematic difference (P = 0.32). DATA CONCLUSION: Integration of low-rank reconstruction with ROCK-MUSIC acquisition may be feasible, and semi-automatic hyperparameter tuning could be effective for generating cardiorespiratory resolved images. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 1.

19.
Nephrol Dial Transplant ; 39(3): 520-530, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-37667508

RESUMO

BACKGROUND: The 2021 clinical guidelines of the Kidney Disease: Improving Global Outcomes emphasize the importance of the histological activity index (AI) in the management of lupus nephritis (LN). Patients with LN and a high AI have poor renal outcomes and high rates of nephritic relapse. In this study we constructed prediction models for the AI in LN. METHODS: The study population comprised 337 patients diagnosed with LN using kidney biopsy. The participants were randomly divided into training and testing cohorts. They were further divided into high-activity (AI >2) and low-activity (AI ≤2) groups. This study developed two clinical prediction models using logistic regression and least absolute shrinkage and selection operator (LASSO) analyses with laboratory test results collected at the time of kidney biopsy. The performance of models was assessed using 5-fold cross-validation and validated in the testing cohort. A nomogram for individual assessment was constructed based on the preferable model. RESULTS: Multivariate analysis showed that higher mean arterial pressure, lower estimated glomerular filtration rate, lower complement 3 level, higher urinary erythrocytes count and anti-double-stranded DNA seropositivity were independent risk factors for high histologic activity in LN. Both models performed well in the testing cohort regarding the discriminatory ability to identify patients with an AI >2. The average area under the curve of 5-fold cross-validation was 0.855 in the logistic model and 0.896 in the LASSO model. A webtool based on the LASSO model was created for clinicians to enter baseline clinical parameters to produce a probability score of an AI >2. CONCLUSIONS: The established nomogram provides a quantitative auxiliary tool for distinguishing LN patients with a high AI and helps physicians make clinical decisions in their comprehensive assessment.


Assuntos
Nefrite Lúpica , Humanos , Nefrite Lúpica/diagnóstico , Nefrite Lúpica/patologia , Nomogramas , Rim/patologia , Taxa de Filtração Glomerular , Projetos de Pesquisa
20.
Artigo em Inglês | MEDLINE | ID: mdl-38695863

RESUMO

Human breast milk contains lactic acid bacteria (LAB), which have an important influence on the composition of the intestinal microbia of infants. In this study, one strain of an α-hemolytic species of the genus Streptococcus, IMAU99199T, isolated from the breast milk of a healthy nursing mother in Hohhot city PR China, was studied to characterise its taxonomic status using phenotypic and molecular taxonomic methods. The results indicated that it represented a member of the mitis-suis clade, pneumoniae subclade of the genus Streptococcus. It is a Gram-stain-positive, catalase-negative and oxidase-negative bacterium, and the cells are globular, paired or arranged in short chains. The results of a phylogenetic analysis of its 16S rRNA gene and two housekeeping genes (gyrB and rpoB) placed it in the genus Streptococcus. A phylogenetic tree based on 135 single-copy genes sequences indicated that IMAU99199T formed a closely related branch well separated from 'Streptococcus humanilactis' IMAU99125, 'Streptococcus bouchesdurhonensis' Marseille Q6994, Streptococcus mitis NCTC 12261T, 'Streptococcus vulneris' DM3B3, Streptococcus toyakuensis TP1632T, Streptococcus pseudopneumoniae ATCC BAA-960T and Streptococcus pneumoniae NCTC 7465T. IMAU99199T and 'S. humanilactis' IMAU99125 had the highest average nucleotide identity (93.7 %) and digital DNA-DNA hybridisation (55.3 %) values, which were below the accepted thresholds for novel species. The DNA G+C content of the draft genome of IMAU99199T was 39.8 %. The main cellular fatty acids components of IMAU99199T were C16 : 0 and C16 : 1ω7. It grew at a temperature range of 25-45 °C (the optimum growth temperature was 37 °C) and a pH range of 5.0-8.0 (the optimum growth pH was 7.0). These data indicate that strain IMAU99199T represents a novel species in the genus Streptococcus, for which the name Streptococcus hohhotensis sp. nov. is proposed. The type strain is IMAU99199T (=GDMCC 1.1874T=KCTC 21155T).


Assuntos
Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano , Ácidos Graxos , Leite Humano , Filogenia , RNA Ribossômico 16S , Análise de Sequência de DNA , Streptococcus , RNA Ribossômico 16S/genética , Humanos , Feminino , China , DNA Bacteriano/genética , Leite Humano/microbiologia , Streptococcus/genética , Streptococcus/isolamento & purificação , Streptococcus/classificação , Ácidos Graxos/análise , Hibridização de Ácido Nucleico , Genes Bacterianos
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