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1.
N Engl J Med ; 385(25): 2325-2335, 2021 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-34739194

RESUMO

BACKGROUND: Among patients with chronic kidney disease (CKD), the use of recombinant human erythropoietin and its derivatives for the treatment of anemia has been linked to a possibly increased risk of stroke, myocardial infarction, and other adverse events. Several trials have suggested that hypoxia-inducible factor (HIF) prolyl hydroxylase inhibitors (PHIs) are as effective as erythropoiesis-stimulating agents (ESAs) in increasing hemoglobin levels. METHODS: In this randomized, open-label, phase 3 trial, we assigned patients with CKD who were undergoing dialysis and who had a hemoglobin level of 8.0 to 11.5 g per deciliter to receive an oral HIF-PHI (daprodustat) or an injectable ESA (epoetin alfa if they were receiving hemodialysis or darbepoetin alfa if they were receiving peritoneal dialysis). The two primary outcomes were the mean change in the hemoglobin level from baseline to weeks 28 through 52 (noninferiority margin, -0.75 g per deciliter) and the first occurrence of a major adverse cardiovascular event (a composite of death from any cause, nonfatal myocardial infarction, or nonfatal stroke), with a noninferiority margin of 1.25. RESULTS: A total of 2964 patients underwent randomization. The mean (±SD) baseline hemoglobin level was 10.4±1.0 g per deciliter overall. The mean (±SE) change in the hemoglobin level from baseline to weeks 28 through 52 was 0.28±0.02 g per deciliter in the daprodustat group and 0.10±0.02 g per deciliter in the ESA group (difference, 0.18 g per deciliter; 95% confidence interval [CI], 0.12 to 0.24), which met the prespecified noninferiority margin of -0.75 g per deciliter. During a median follow-up of 2.5 years, a major adverse cardiovascular event occurred in 374 of 1487 patients (25.2%) in the daprodustat group and in 394 of 1477 (26.7%) in the ESA group (hazard ratio, 0.93; 95% CI, 0.81 to 1.07), which also met the prespecified noninferiority margin for daprodustat. The percentages of patients with other adverse events were similar in the two groups. CONCLUSIONS: Among patients with CKD undergoing dialysis, daprodustat was noninferior to ESAs regarding the change in the hemoglobin level from baseline and cardiovascular outcomes. (Funded by GlaxoSmithKline; ASCEND-D ClinicalTrials.gov number, NCT02879305.).


Assuntos
Anemia/tratamento farmacológico , Barbitúricos/uso terapêutico , Darbepoetina alfa/uso terapêutico , Epoetina alfa/uso terapêutico , Glicina/análogos & derivados , Hematínicos/uso terapêutico , Diálise Renal , Insuficiência Renal Crônica/complicações , Idoso , Anemia/etiologia , Barbitúricos/efeitos adversos , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/mortalidade , Darbepoetina alfa/efeitos adversos , Epoetina alfa/efeitos adversos , Feminino , Glicina/efeitos adversos , Glicina/uso terapêutico , Hematínicos/efeitos adversos , Hemoglobinas/análise , Humanos , Prolina Dioxigenases do Fator Induzível por Hipóxia/antagonistas & inibidores , Análise de Intenção de Tratamento , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/terapia , Acidente Vascular Cerebral/epidemiologia
2.
Clin Genet ; 106(5): 638-643, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39003656

RESUMO

Intellectual disability (ID) is a kind of nervous developmental disorder and affects more than 1% of people worldwide. SLC45A1 as a transmembrane protein is implicated in the regulation of glucose homoeostasis. Through trio-based exome sequencing, the missense mutations of SLC45A1 c.103G>A (p.V35M) and c.1211T>G (p.F404C) were identified in the proband with syndromic ID. The distribution, expression and activity of SLC45A1 wild-type (WT) and variants were assayed in transfected COS7 cells. In SLC45A1 variants, the hydrogen bonds surrounding the 35th and 404th amino acid were changed, location on the cytomembrane was failed, their activity to transport glucose was also significantly decreased to contrast with SLC45A1-WT. No difference was observed at the mRNA and protein level. In conclusion, the compound heterozygous variants of SLC45A1 might be the genetic etiology for syndromic ID. These novel mutations probably attenuated its activity to transport glucose by the alteration of tertiary structure and failure of intracellular location.


Assuntos
Heterozigoto , Deficiência Intelectual , Humanos , Deficiência Intelectual/genética , Deficiência Intelectual/patologia , Células COS , Chlorocebus aethiops , Masculino , Animais , Sequenciamento do Exoma , Feminino , Mutação de Sentido Incorreto/genética , Predisposição Genética para Doença , Linhagem , Mutação/genética , Glucose/metabolismo
3.
J Anat ; 244(3): 527-536, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38009263

RESUMO

Corticotropin-releasing hormone (CRH) neurons are densely distributed in the medial prefrontal cortex (mPFC), which plays a crucial role in integrating and processing emotional and cognitive inputs from other brain regions. Therefore, it is important to know the neural afferent patterns of mPFCCRH neurons, which are still unclear. Here, we utilized a rabies virus-based monosynaptic retrograde tracing system to map the presynaptic afferents of the mPFCCRH neurons throughout the entire brain. The results show that the mPFCCRH neurons receive inputs from three main groups of brain regions: (1) the cortex, primarily the orbital cortex, somatomotor areas, and anterior cingulate cortex; (2) the thalamus, primarily the anteromedial nucleus, mediodorsal thalamic nucleus, and central medial thalamic nucleus; and (3) other brain regions, primarily the basolateral amygdala, hippocampus, and dorsal raphe nucleus. Taken together, our results are valuable for further investigations into the roles of the mPFCCRH neurons in normal and neurological disease states. These investigations can shed light on various aspects such as cognitive processing, emotional modulation, motivation, sociability, and pain.


Assuntos
Encéfalo , Hormônio Liberador da Corticotropina , Camundongos , Animais , Neurônios/fisiologia , Córtex Pré-Frontal/fisiologia , Mapeamento Encefálico , Vias Neurais/fisiologia
4.
Opt Express ; 32(9): 15760-15773, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38859218

RESUMO

Fluorescence molecular tomography (FMT) serves as a noninvasive modality for visualizing volumetric fluorescence distribution within biological tissues, thereby proving to be an invaluable imaging tool for preclinical animal studies. The conventional FMT relies upon a point-by-point raster scan strategy, enhancing the dataset for subsequent reconstruction but concurrently elongating the data acquisition process. The resultant diminished temporal resolution has persistently posed a bottleneck, constraining its utility in dynamic imaging studies. We introduce a novel system capable of simultaneous FMT and surface extraction, which is attributed to the implementation of a rapid line scanning approach and dual-camera detection. The system performance was characterized through phantom experiments, while the influence of scanning line density on reconstruction outcomes has been systematically investigated via both simulation and experiments. In a proof-of-concept study, our approach successfully captures a moving fluorescence bolus in three dimensions with an elevated frame rate of approximately 2.5 seconds per frame, employing an optimized scan interval of 5 mm. The notable enhancement in the spatio-temporal resolution of FMT holds the potential to broaden its applications in dynamic imaging tasks, such as surgical navigation.


Assuntos
Imageamento Tridimensional , Imagens de Fantasmas , Imageamento Tridimensional/métodos , Fluorescência , Animais , Imagem Óptica/métodos , Luz
5.
Opt Lett ; 49(4): 1065-1068, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38359254

RESUMO

For most imaging systems, there is a trade-off between spatial resolution, temporal resolution, and signal-to-noise ratio. Such a trade-off is particularly severe in single-pixel imaging systems, given the limited throughput of the only one available pixel. Here we report a real-time single-pixel imaging method that can adaptively balance the spatial resolution, temporal resolution, and signal-to-noise ratio of the imaging system according to the changes in the target scene. When scene changes are detected, the dynamic imaging mode will be activated. The temporal resolution will be given high priority and real-time single-pixel imaging will be conducted at a video frame rate (30 frames/s) to visualize the object motion. When no scene changes are detected, the static imaging mode will be activated. The spatial resolution and the signal-to-noise ratio will be progressively built up to resolve fine structures and to improve image quality. The proposed method not only adds practicability to single-pixel imaging, but also generates a new, to the best of our knowledge, insight in data redundancy reduction and information capacity improvement for other computational imaging schemes.

6.
Exp Eye Res ; 248: 110096, 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39278392

RESUMO

PURPOSE: This study focused on the mechanisms of pyroptosis and oxidative damage exacerbation by NOD-like receptor thermal protein domain associated protein 3 (NLRP3) during the infection of canine corneal epithelial cells (CCECs) with Staphylococcus pseudintermedius. METHODS: The CCECs treated with dimethyl fumarate (DMF), recombinant high mobility group protein 1 (HMGB1), or N-acetylcysteine (NAC). The gasdermin (GSDM) family and HMGB1 mRNA expression levels were detected using quantitative reverse transcription polymerase chain reaction. Lactate dehydrogenase activity, bacterial counts, the pyroptosis rate, reactive oxygen species (ROS) content, and antioxidant enzyme activity were used to reflect pyroptosis and oxidation level. RESULTS: Regulation of NLRP3 significantly affected the pyroptosis rate and GSDMD-N expression levels during S. pseudintermedius infection. Inhibition of GSDMD-N protein activation by DMF reversed the exacerbation of pyroptosis induced by NLRP3 overexpression and reduced the levels of cleaved interleukin-1ß (IL-1ß), cleaved cysteinyl aspartate-specific protease-1, and NLRP3. In addition, NLRP3 was found to target the HMGB1 promoter and regulate its protein expression, to increase ROS accumulation and GSDMD-N expression levels, and activate the NLRP3-HMGB1-ROS-GSDMD signaling axis to aggravate pyroptosis during infection. CONCLUSIONS: NLRP3 aggravates pyroptosis and oxidative damage associated with the activation of NLRP3-GSDMD and NLRP3-HMGB1-ROS-GSDMD signaling pathways during the infection of CCECs with S. pseudintermedius.

7.
Am J Geriatr Psychiatry ; 32(10): 1244-1258, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38763834

RESUMO

OBJECTIVE: The study was designed to examine the effects of simultaneous combination of aerobic exercise and video game training on executive functions (EFs) and brain functional connectivity in older adults. DESIGN: A four-armed, quasi-experimental study. SETTING AND PARTICIPANTS: Community-dwelling adults aged 55 years and older. METHODS: A total of 97 older adults were divided into one of four groups: aerobic exercise (AE), video game (VG), combined intervention (CI), and passive control (PC). Participants in intervention groups received 32 sessions of training over a 4-month period at a frequency of twice a week. EFs was evaluated using a composite score derived from a battery of neuropsychological tests. The Montreal Cognitive Assessment (MoCA) was employed to evaluate overall cognitive function, while the 6-Minute Walking Test (6MWT) was utilized to gauge physical function. Additionally, the functional connectivity (FC) of the frontal-parietal networks (FPN) was examined as a neural indicator of cognitive processing and connectivity changes. RESULTS: In terms of EFs, both VG and CI groups demonstrated improvement following the intervention. This improvement was particularly pronounced in the CI group, with a large effect size (Hedge's g = 0.83), while the VG group showed a medium effect size (Hedge's g = 0.56). A significant increase in MoCA scores was also observed in both the VG and CI groups, whereas a significant increase in 6MWT scores was observed in the AE and CI groups. Although there were no group-level changes observed in FC of the FPN, we found that changes in FC was behaviorally relevant as increased FC was associated with greater improvement in EFs. CONCLUSION: The study offers preliminary evidence that both video game training and combined intervention could enhance EFs in older adults. Simultaneous combined intervention may hold greater potential for facilitating EFs gains. The initial evidence for correlated changes in brain connectivity and EFs provides new insights into understanding the neural basis underlying the training gains.


Assuntos
Função Executiva , Exercício Físico , Jogos de Vídeo , Humanos , Masculino , Função Executiva/fisiologia , Idoso , Feminino , Exercício Físico/fisiologia , Pessoa de Meia-Idade , Terapia por Exercício/métodos , Imageamento por Ressonância Magnética , Encéfalo/fisiologia , Encéfalo/diagnóstico por imagem , Testes Neuropsicológicos , Conectoma/métodos , Vida Independente
8.
Wound Repair Regen ; 32(2): 123-134, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38151814

RESUMO

Scald is a common skin injury in daily life. It is well known that skin burns are associated with inflammation and oxidative stress. In our previous study, we found that Abelmoschus manihot (L.) medik had excellent therapeutic effects on scald-induced inflammation, but its effect on scald-induced oxidative stress was not reported. In this study, a deep second-degree scald model in mice was established, and the wound healing rate, healing time, malondialdehyde (MDA) and total superoxide dismutase (T-SOD) levels, and nuclear factor erythroid 2-related Factor 2 (Nrf2) expression in wound tissue were measured to evaluate the scald wound healing performance of extraction from A. manihot (L.) medik (EAM). Scalding activity in mice was examined in vivo by hot water-induced finger swelling. The treatment scald activities were also examined in vivo by subjecting mice to thermal water-induced digit swelling. Additionally, the antioxidant effect of EAM on fibroblasts was also used to determine the mechanism in vitro. The results showed that EAM not only decreased the wound healing time but also effectively regulated the levels of oxidising, MDA and T-SOD in wound tissue. Concurrently, EAM suppressed digit swelling and hyperalgesia. Furthermore, EAM had a significant protective effect on NIH-3T3 cells after H2 O2 injury by regulating the Nrf2 signalling pathway against oxidative injury. Therefore, EAM is a promising drug for the treatment of scald-induced inflammation.


Assuntos
Abelmoschus , Queimaduras , Camundongos , Animais , Antioxidantes/farmacologia , Abelmoschus/metabolismo , Fator 2 Relacionado a NF-E2 , Cicatrização , Queimaduras/tratamento farmacológico , Queimaduras/metabolismo , Inflamação , Edema , Flores/metabolismo , Superóxido Dismutase/metabolismo , Água
9.
Nutr Metab Cardiovasc Dis ; 34(1): 112-120, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37798237

RESUMO

BACKGROUND AND AIM: Stroke incidence rates are rising among young adults. Liver fibrosis has recently been recognized as a risk factor for cardiovascular events and stroke in the general population. It remains unclear whether liver fibrosis influences the prognosis of stroke. We aimed to evaluate the association between liver fibrosis and stroke recurrence in young stroke patients. METHODS AND RESULTS: Young adults with first-ever ischemic stroke were enrolled from a prospective stroke registry and were followed up for stroke recurrence. Liver fibrosis was evaluated by Fibrosis-4 (FIB-4) score and was stratified into three categories. Cox regression analysis was performed to assess the relationship between liver fibrosis and stroke recurrence. Over a median follow-up of 3.1 (1.7-4.6) years, 72 (11.6%) recurrent strokes occurred among 621 patients. According to the FIB-4 score, 73 (11.7%) patients had indeterminate fibrosis, while 11 (1.8%) had advanced fibrosis. Univariate Cox analysis revealed that patients with a high FIB-4 score were more likely to experience stroke recurrence than those with a low FIB-4 score (hazard ratio 3.748, 95% confidence interval 1.359-10.332, P = 0.011). After adjusting for potential confounders in the multivariate analysis, FIB-4 score remained an independent risk factor. CONCLUSIONS: Young stroke patients with advanced liver fibrosis were at a greater risk of stroke recurrence. Evaluating liver fibrosis may provide valuable information for stroke risk stratification, and the FIB-4 score could serve as a useful tool.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Adulto Jovem , Humanos , Seguimentos , Recidiva , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Cirrose Hepática/diagnóstico , Cirrose Hepática/epidemiologia , Fatores de Risco , Fibrose
10.
J Nanobiotechnology ; 22(1): 641, 2024 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-39425081

RESUMO

BACKGROUND: Subarachnoid hemorrhage (SAH) is a life -threatening cerebrovascular disease, where early brain injury (EBI) stands as a primary contributor to mortality and unfavorable patient outcomes. Neuronal ferroptosis emerges as a key pathological mechanism underlying EBI in SAH. Targeting ferroptosis for therapeutic intervention in SAH holds significant promise as a treatment strategy. METHODS: SAH model was induced via intravascular puncture and quantitatively assessed the presence of neuronal ferroptosis in the early phase of SAH using FJC staining, Prussian blue staining, as well as malondialdehyde (MDA) and glutathione (GSH) measurements. Hyaluronic acid-coated ursolic acid nanoparticles (HA-PEG-UA NPs) were prepared using the solvent evaporation method. We investigated the in vivo distribution of HA-PEG-UA NPs in SAH model through IVIS and fluorescence observation, and examined their impact on short-term neurological function and cortical neurological injury. Finally, we assessed the effect of UA on the Nrf-2/SLC7A11/GPX4 axis via Western Blot analysis. RESULTS: We successfully developed self-assembled UA NPs with hyaluronic acid to target the increased CD44 expression in the SAH-afflicted brain. The resulting HA-PEG-UA NPs facilitated delivery and enrichment of UA within the SAH-affected region. The targeted delivery of UA to the SAH region can effectively inhibit neuronal ferroptosis, improve neurological deficits, and prognosis in mice. Its mechanism of action is associated with the activation of the Nrf-2/SLC7A11/GPX4 signaling pathway. CONCLUSIONS: Brain-targeted HA-PEG-UA NPs was successfully developed and hold the potential to enhance SAH prognosis by limiting neuronal ferroptosis via modulation of the Nrf-2/SLC7A11/GPX4 signal.


Assuntos
Encéfalo , Ferroptose , Ácido Hialurônico , Fator 2 Relacionado a NF-E2 , Nanopartículas , Hemorragia Subaracnóidea , Triterpenos , Ácido Ursólico , Animais , Triterpenos/farmacologia , Triterpenos/química , Ferroptose/efeitos dos fármacos , Camundongos , Hemorragia Subaracnóidea/tratamento farmacológico , Nanopartículas/química , Fator 2 Relacionado a NF-E2/metabolismo , Ácido Hialurônico/química , Ácido Hialurônico/farmacologia , Masculino , Encéfalo/metabolismo , Encéfalo/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Modelos Animais de Doenças , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Sistema y+ de Transporte de Aminoácidos
11.
Pharmacology ; : 1-13, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39250889

RESUMO

BACKGROUND: Cardiovascular diseases are now the second leading cause of death among cancer patients. Heart injury in patients with terminal cancer can lead to significant deterioration of left ventricular morphology and function. This specific heart condition is known as cancer-induced cardiac cachexia (CICC) and is characterized by cardiac dysfunction and wasting. However, an effective pharmacological treatment for CICC remains elusive. SUMMARY: The development and progression of CICC are closely related to pathophysiological processes, such as protein degradation, oxidative responses, and inflammation. Traditional Chinese medicine (TCM) monomers offer unique advantages in reversing heart injury, which is the end-stage manifestation of CICC except the regular treatment. This review outlines significant findings related to the impact of eleven TCM monomers, namely Astragaloside IV, Ginsenosides Rb1, Notoginsenoside R1, Salidroside, Tanshinone II A, Astragalus polysaccharides, Salvianolate, Salvianolic acids A and B, and Ginkgolide A and B, on improving heart injury. These TCM monomers are potential therapeutic agents for CICC, each with specific mechanisms that could potentially reverse the pathological processes associated with CICC. Advanced drug delivery strategies, such as nano-delivery systems and exosome-delivery systems, are discussed as targeted administration options for the therapy of CICC. KEY MESSAGE: This review summarizes the pathological mechanisms of CICC and explores the pharmacological treatment of TCM monomers that promote anti-inflammation, antioxidation, and pro-survival. It also considers pharmaceutical strategies for administering TCM monomers, highlighting their potential as therapies for CICC.

12.
Ecotoxicol Environ Saf ; 272: 116074, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38350214

RESUMO

The effect of underwater noise environment generated by equipment in industrial recirculating aquaculture systems (RAS) on fish is evident. However, different equipment generate noise in various frequency ranges. Understanding the effects of different frequency ranges noise on cultured species is important for optimizing the underwater acoustic environment in RAS. Given this, the effects of underwater noise across various frequency bands in RAS on the growth, physiology, and collective behavior of juvenile largemouth bass (Micropterus salmoides) were comprehensively evaluated here. In this study, three control groups were established: low-frequency noise group (80-1000 Hz, 117 dB re 1µPa RMS), high-frequency noise group (1-19 kHz, 117 dB re 1µPa RMS), and ambient group. During a 30-day experiment, it was found that: 1) industrial RAS noise with different frequency bands all had a certain inhibitory effect on the growth of fish, which the weight gain rate and product of length and depth of caudal peduncle in the ambient group were significantly higher than those of the two noise groups, with the low-frequency noise group showing significantly lower values than the high-frequency noise group; 2) industrial RAS noise had a certain degree of adverse effect on the digestive ability of fish, with the low-frequency noise group being more affected; 3) industrial RAS noise affected the collective feeding behavior of fish, with the collective feeding signal propagation efficiency and feeding intensity of the noise groups being significantly lower than those of the ambient group, and the high-frequency noise group performing better than the low-frequency noise group as a whole therein. From the above, the underwater noise across different frequency bands generated by equipment operation in industrial RAS both had an impact on juvenile largemouth bass, with the low-frequency noise group being more severely affected.


Assuntos
Bass , Animais , Bass/fisiologia , Aquicultura
13.
Sensors (Basel) ; 24(18)2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39338676

RESUMO

With the development of the IoT, Wireless Rechargeable Sensor Networks (WRSNs) derive more and more application scenarios with diverse performance requirements. In scenarios where the energy consumption rate of sensor nodes changes dynamically, most existing charging scheduling methods are not applicable. The incorrect estimation of node energy requirement may lead to the death of critical nodes, resulting in missing events. To address this issue, we consider both the spatial imbalance and temporal dynamics of the energy consumption of the nodes, and minimize the Event Missing Rate (EMR) as the goal. Firstly, an Energy Consumption Balanced Tree (ECBT) construction method is proposed to prolong the lifetime of each node. Then, we transform the goal into Maximizing the value of the Evaluation function of each node's Energy Consumption Rate prediction (MEECR). Afterwards, the setting of the evaluation function is explored and the MEECR is further transformed into a variant of the knapsack problem, namely "the alternating backpack problem", and solved by dynamic programming. After predicting the energy consumption rate of the nodes, a charging scheduling scheme that meets the Dual Constraints of Nodes' energy requirements and MC's capability (DCNM) is developed. Simulations demonstrate the advantages of the proposed method. Compared to the baselines, the EMR was reduced by an average of 35.2% and 26.9%.

14.
Sensors (Basel) ; 24(12)2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38931630

RESUMO

Modal parameter estimation is crucial in vibration-based damage detection and deserves increased attention and investigation. Concrete arch dams are prone to damage during severe seismic events, leading to alterations in their structural dynamic characteristics and modal parameters, which exhibit specific time-varying properties. This highlights the significance of investigating the evolution of their modal parameters and ensuring their accurate identification. To effectively accomplish the recursive estimation of modal parameters for arch dams, an adaptive recursive subspace (ARS) method with variable forgetting factors was proposed in this study. In the ARS method, the variable forgetting factors were adaptively updated by assessing the change rate of the spatial Euclidean distance of adjacent modal frequency identification values. A numerical simulation of a concrete arch dam under seismic loading was conducted by using ABAQUS software, in which a concrete damaged plasticity (CDP) model was used to simulate the dam body's constitutive relation, allowing for the assessment of damage development under seismic loading. Utilizing the dynamic responses obtained from the numerical simulation, the ARS method was implemented for the modal parameter recursive estimation of the arch dam. The identification results revealed a decreasing trend in the frequencies of the four initial modes of the arch dam: from an undamaged state characterized by frequencies of 0.910, 1.166, 1.871, and 2.161 Hz to values of 0.895, 1.134, 1.842, and 2.134 Hz, respectively. Concurrently, increases in the damping ratios of these modes were observed, transitioning from 4.44%, 4.28%, 5.42%, and 5.56% to 4.98%, 4.91%, 6.61%, and 6.85%%, respectively. The correlation of the identification results with damage progression validated the effectiveness of the ARS method. This study's outcomes have substantial theoretical and practical importance, facilitating the immediate comprehension of the dynamic characteristics and operational states of concrete arch dam structures.

15.
Neuroimage ; 279: 120321, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37574119

RESUMO

Accurate stroke assessment and consequent favorable clinical outcomes rely on the early identification and quantification of aneurysmal subarachnoid hemorrhage (aSAH) in non-contrast computed tomography (NCCT) images. However, hemorrhagic lesions can be complex and difficult to distinguish manually. To solve these problems, here we propose a novel Hybrid 2D/3D UNet deep-learning framework for automatic aSAH identification and quantification in NCCT images. We evaluated 1824 consecutive patients admitted with aSAH to four hospitals in China between June 2018 and May 2022. Accuracy and precision, Dice scores and intersection over union (IoU), and interclass correlation coefficients (ICC) were calculated to assess model performance, segmentation performance, and correlations between automatic and manual segmentation, respectively. A total of 1355 patients with aSAH were enrolled: 931, 101, 179, and 144 in four datasets, of whom 326 were scanned with Siemens, 640 with Philips, and 389 with GE Medical Systems scanners. Our proposed deep-learning method accurately identified (accuracies 0.993-0.999) and segmented (Dice scores 0.550-0.897) hemorrhage in both the internal and external datasets, even combinations of hemorrhage subtypes. We further developed a convenient AI-assisted platform based on our algorithm to assist clinical workflows, whose performance was comparable to manual measurements by experienced neurosurgeons (ICCs 0.815-0.957) but with greater efficiency and reduced cost. While this tool has not yet been prospectively tested in clinical practice, our innovative hybrid network algorithm and platform can accurately identify and quantify aSAH, paving the way for fast and cheap NCCT interpretation and a reliable AI-based approach to expedite clinical decision-making for aSAH patients.


Assuntos
Aprendizado Profundo , Acidente Vascular Cerebral , Hemorragia Subaracnóidea , Humanos , Hemorragia Subaracnóidea/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Meios de Contraste
16.
Eur J Neurosci ; 58(8): 3892-3902, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37779210

RESUMO

The supraspinal mechanism plays a key role in developing and maintaining chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS). However, it is not clear how white matter changes in young and middle-aged males with CP/CPPS. In this cross-sectional study, 23 CP/CPPS patients and 22 healthy controls (HCs) were recruited. Tract-based spatial statistics was applied to investigate the differences in diffusion tensor imaging metrics, including fractional anisotropy (FA), mean diffusion (MD), radial diffusion (RD) and axial diffusion (AD), between CP/CPPS patients and HCs. The study also examined the association between white matter alterations and clinical variables in patients using correlation analysis. Compared with HCs, patients showed decreased FA, MD, RD and AD in the body and genu of the corpus callosum and right anterior corona radiata. In addition, they showed increased FA along with decreased MD, RD and AD in the left posterior limb of the internal capsule (PLIC-L), left external capsule and left cerebral peduncle. The FA of PLIC-L was negatively correlated with disease duration (r = -.54, corrected p = .017), while MD and RD were positively correlated (r = .45, corrected p = .042; r = .57, corrected p = .017). These results suggest that CP/CPPS is associated with extensive changes in white matter tracts, which are involved in pain processing. In particular, the FA, MD and RD values in the PLIC-L were correlated with the disease duration, indicating that the long-term course of CP/CPPS may have effects on the white matter microstructure of the pain perception pathways.


Assuntos
Prostatite , Substância Branca , Masculino , Pessoa de Meia-Idade , Humanos , Substância Branca/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Estudos Transversais , Prostatite/diagnóstico por imagem , Dor Pélvica/diagnóstico por imagem
17.
Hum Brain Mapp ; 44(3): 989-1001, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36269166

RESUMO

Neurovascular (NV) decoupling is a potential neuropathologic mechanism of cognitive impairment in patients with end-stage renal disease (ESRD). Hemodialysis improves cognitive impairment at 24 h post-dialysis, which suggests a potential neuroprotective effect of hemodialysis treatment on the brain. We investigated the effects of hemodialysis treatment on the reversal of NV decoupling associated with cognitive improvement. A total of 39 patients with ESRD and 39 healthy controls were enrolled. All patients were imaged twice during a dialysis session: before hemodialysis (T1pre-dialysis ) and at 24 h after dialysis (T2post-dialysis ). The healthy controls were imaged once. NV coupling was characterized based on correlation coefficients between four types of blood oxygen level-dependent signals and cerebral blood flow (CBF). A battery of neuropsychological and blood tests was performed before the imaging. Patients with ESRD showed improvements in memory and executive function at T2post-dialysis compared with that at T1pre-dialysis . At both T1pre-dialysis and T2post-dialysis , patients with ESRD had lower amplitude of low-frequency fluctuation (ALFF)-CBF coupling than healthy controls. Additionally, patients with ESRD had higher ALFF-CBF coupling at T2post-dialysis than at T1pre-dialysis . Higher memory scores, higher hemoglobin level, lower total plasma homocysteine level, lower systolic blood pressure variance, and lower ultrafiltration volume were associated with higher ALFF-CBF coupling in patients with ESRD after a hemodialysis session. These findings indicate that partial correction of anemia and hyperhomocysteinemia, stable systolic blood pressure, and fluid restriction may be closely linked to the reversal of NV decoupling and improvement in cognition in patients with ESRD.


Assuntos
Disfunção Cognitiva , Falência Renal Crônica , Humanos , Imageamento por Ressonância Magnética/métodos , Diálise Renal , Falência Renal Crônica/complicações , Falência Renal Crônica/diagnóstico por imagem , Falência Renal Crônica/terapia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/terapia , Encéfalo/diagnóstico por imagem
18.
Am J Geriatr Psychiatry ; 31(10): 808-819, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37164780

RESUMO

OBJECTIVE: Older adults with subjective memory complaints (SMC) have a higher risk of dementia and commonly demonstrate symptoms of anxiety. This study examined the neural correlates of group counseling (GC)-boosted memory training (MT) gains. DESIGN: This study was an active, controlled, randomized trial. SETTING: Neighborhoods near the Institute of Psychology of the Chinese Academy of Sciences (CAS). PARTICIPANTS: Community-dwelling older adults, aged 60 or above with a minimum of 6 years of education, were recruited through advertisements and flyers posted at community service stations. MEASUREMENTS: The amplitude of low-frequency fluctuations and resting-state functional connectivity (rs-FC) analyses were used to examine the neural correlates associated with MT gains enhanced by improved mood in older adults with SMC. Participants were randomly assigned to the combined intervention (CI) or GC group. The CI group received 3 weeks of GC followed by 4 weeks of MT, and the GC group received GC and health lectures. Cognitive function and emotions were assessed before GC (T1), after GC (T2), and after MT (T3). Both groups underwent resting-state functional magnetic resonance imaging scanning at T2 and T3. RESULTS: Alleviated anxiety was positively correlated with rs-FC between the amygdala and left hippocampus and negatively correlated with rs-FC between the amygdala and right hippocampus. MT improvement was negatively correlated with rs-FC between the amygdala and right hippocampus in the CI group; the correlation was not significant after controlling for emotional changes. CONCLUSIONS: Amygdala-hippocampal connectivity may be associated with improved mood-enhanced MT gains in individuals with SMC.


Assuntos
Tonsila do Cerebelo , Treino Cognitivo , Humanos , Idoso , Tonsila do Cerebelo/diagnóstico por imagem , Lobo Temporal , Emoções , Hipocampo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos
19.
Am J Geriatr Psychiatry ; 31(3): 197-209, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36414488

RESUMO

OBJECTIVE: We sought to assess cognitive benefits of a community-based multidomain intervention for improving cognition among older adults at risk of cognitive decline (COMBAT). DESIGN: A two-armed cluster-randomized controlled trial. SETTING AND PARTICIPANTS: Community-dwelling older adults aged 60 years or older and were at risk of cognitive decline (n = 209). INTERVENTION: In this 9-month intervention study, 10 community hospitals in Beijing, China, were randomized (1:1) to receive either a multidomain intervention of meditation, cognitive training, exercise, and nutrition counseling or usual care. The intervention was delivered with weekly 1-hour group training sessions and weekly home homework. MEASUREMENTS: Primary outcome was change in cognition as measured by a composite Z score of seven cognitive tests. Secondary outcomes included subjective cognitive abilities, positive and negative affective experiences, physical activity, and dietary habits. Assessments were administered at baseline, end of the intervention, and 1 year after completing the intervention (1-year follow-up). RESULTS: Immediately after the intervention, the intervention group showed significant enhancement in cognitive performance (p = 0.026). The between-group difference in the Z score of change of cognition was 0.20 (95% CI: 0.053, 0.35), with a Hedges' g of 0.40 (95% CI: 0.29, 0.50). However, this cognitive benefit was not significant at 1-year follow-up. CONCLUSION: This multidomain intervention was effective to improve cognition for at-risk individuals. Long-term effects on cognitive function and individual differences in response to the intervention deserve further investigation.


Assuntos
Disfunção Cognitiva , Humanos , Idoso , Disfunção Cognitiva/prevenção & controle , Cognição , Exercício Físico , China
20.
Endocr J ; 70(9): 891-900, 2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37344390

RESUMO

Haemoglobin A1c (HbA1c) variability, a metric reflecting long-term glycaemic fluctuation, is associated with macrovascular events in type 2 diabetes. We aimed to investigate the impacts of HbA1c variability on preclinical atherosclerosis in patients without prior cardiovascular disease. We conducted a cross-sectional study on 564 participants with diabetes who underwent general health checkups from 2016-2022. At least three HbA1c measurements were conducted for each patient. Carotid intima-media thickness (CIMT) and plaque were evaluated by B-mode ultrasonography on bilateral carotid common arteries. The standard deviation (SD) and coefficient of variance (CV) of HbA1c were calculated. We found that each doubling in CV-HbA1c and SD-HbA1c was associated with a significant increment in CIMT. The effects were more pronounced in the groups with higher mean-HbA1c (mean-HbA1c ≥6.5%). The odds ratio (95% confidence interval) for the carotid plaque was 2.68 (1.57, 4.56) and 2.88 (1.16, 5.13) in the third tertile of CV-HbA1c and SD-HbA1c respectively after fully adjusting for all the conventional risk factors in the multivariable logistic regression analysis. High mean-HbA1c plus the third tertile of HbA1c variability sharply increased the prevalence of carotid plaques. In conclusion, HbA1c variability was independently associated with CIMT and plaques in populations with diabetes. CV-HbA1c and SD-HbA1c had more effects on subclinical atherosclerosis in patients with poorly-controlled blood glucose levels.


Assuntos
Aterosclerose , Doenças das Artérias Carótidas , Diabetes Mellitus Tipo 2 , Placa Aterosclerótica , Humanos , Espessura Intima-Media Carotídea , Diabetes Mellitus Tipo 2/complicações , Hemoglobinas Glicadas , Estudos Transversais , Estudos Retrospectivos , Placa Aterosclerótica/complicações , Placa Aterosclerótica/diagnóstico por imagem , Aterosclerose/diagnóstico por imagem , Aterosclerose/epidemiologia , Fatores de Risco , Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/epidemiologia
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