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1.
Nat Commun ; 15(1): 6967, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39138177

RESUMO

Revealing key factors that modulate the regioselectivity in heterogeneous hydroformylation requires identifying and monitoring the dynamic evolution of the truly active center under real reaction conditions. However, unambiguous in situ characterizations are still lacking. Herein, we elaborately construct a series of Rh-POPs catalysts for propylene hydroformylation which exhibited tunable regioselectivity. Multi-technique approaches reveal the unique microenvironment of the diverse HRh(CO)(PPh3-frame)2 sites with distinct P-Rh-P bite angles ranging from 90° to 120° and 158° to 168°, respectively. In situ time-resolved XAFS, FT-IR, and quasi-in situ Solid-state NMR experiments combined with DFT calculations explain the dynamic evolution of the electronic and coordinate state of the distinct active sites induced by hemilabile PPh3-frame ligands and further disclose the regulatory mechanism of regioselectivity. These state-of-the-art techniques and multiscale analysis advance the understanding of how hemilabile coordination influences regioselectivity and will provide a new thought to modulate the regioselectivity in future industrial processes.

2.
J Thorac Dis ; 16(7): 4106-4119, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39144348

RESUMO

Background: Neoadjuvant therapy has become a mainstay of treatment for locally advanced resectable esophageal cancer. The objective of this research was to investigate the effectiveness and safety of neoadjuvant immunotherapy combined with chemotherapy in treating surgically removable esophageal squamous cell carcinoma (ESCC). Methods: From January 1, 2016 to April 1, 2023, we conducted a retrospective analysis of patients diagnosed with resectable esophageal cancer who underwent neoadjuvant immunotherapy combined with chemotherapy at The First Affiliated Hospital of Nanchang University. The primary endpoints of this study were pathologic complete response (pCR), major pathologic response (MPR) and disease-free survival (DFS). The secondary endpoints of this study were overall survival (OS), objective response rate (ORR) and safety. Results: A total of 122 patients with ESCC receiving neoadjuvant immune-chemotherapy (nICT) were included. Fifty-four patients achieved partial response (PR) and two patients achieved complete response (CR), with an ORR of 45.9%. Of the 106 patients who underwent surgery, a total of 28 patients achieved pCR (26.4%) and a total of 37 patients achieved MPR (34.9%). Grade 3 or higher adverse events occurred in 26 patients (21.3%). The most common postoperative complication was pneumonitis (25.5%). Conclusions: Neoadjuvant immunotherapy combined with chemotherapy demonstrates satisfactory efficacy in the treatment of locally advanced ESCC, with manageable treatment-related adverse events and postoperative complications.

3.
Food Chem X ; 23: 101646, 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-39139485

RESUMO

The quality of strong-flavor Baijiu, a prominent Chinese liquor, is intricately tied to the choice of sorghum variety used in fermentation. However, a significant gap remains in our understanding of how glutinous and non-glutinous sorghum varieties comprehensively impact Baijiu flavor formation through fermentation metabolites. This study employed untargeted metabolomics combined with feature-based molecular networking (FBMN) to explore the unique metabolic characteristics of these two sorghum varieties during fermentation. FBMN analysis revealed 267 metabolites within both types of fermented sorghum (Zaopei) in the cellar. Further multidimensional statistical analyses highlighted sphingolipids, 2,5-diketopiperazines, and methionine derivatives as critical markers for quality control. These findings represent a significant advancement in our understanding and provide valuable insights for regulating the quality of Baijiu flavors.

4.
Environ Toxicol ; 2024 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-39155575

RESUMO

Various studies have demonstrated that ubiquitin D (UBD) is overexpressed in different cancer types and may serve as a potential prognostic factor. However, additional research is necessary to establish the prognostic significance and possible role of UBD in glioma. Transcriptomic expression data from The Cancer Genome Atlas database (TCGA) and Chinese Glioma Genome Atlas (CGGA) were analyzed to identify UBD expression differences in tumor and normal tissues. The relative levels of UBD in glioma and normal tissues were determined using qRT-PCR and WB. Logistic regression analysis was performed to investigate the association between UBD expression and clinicopathological characteristics of glioma patients. To evaluate the diagnostic and prognostic predictive values of UBD, we used Kaplan-Meier survival curves, Cox regression analysis, diagnostic receiver operating characteristic (ROC) curves, and nomogram model. We also conducted wound healing assays, transwell assays, EdU assays, and colony formation assays to verify the UBD function. Gene ontology (GO) enrichment analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, as well as gene set enrichment analysis (GSEA), were employed to determine the functions of UBD. Finally, we performed the western blot assays to assess changes in EMT markers as well as p-PI3K, p-AKT, and p-mTOR expressions. Our study revealed a remarkable increase of UBD expression in glioma samples. Cox regression analysis demonstrated that high expression of UBD mRNA was an independent prognostic factor for overall survival (OS) in TCGA. ROC curve analysis showed that UBD expression levels could differentiate glioma from adjacent normal tissues accurately. Additionally, knockdown of UBD reduced the migration, invasion, and proliferation ability of glioma cells while UBD overexpression had the opposite effect. GSEA showed that the expression of UBD involved with various pathways including epithelial-mesenchymal transition (EMT), PI3K-AKT-mTOR signaling, P53 pathway, angiogenesis, inflammatory response, KRAS signaling, hypoxia, as well as TGF-ß signaling. Furthermore, our findings suggest that UBD accelerates the activation of EMT and PI3K/AKT/mTOR pathway.

5.
Chem Sci ; 15(32): 13032-13040, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39148807

RESUMO

The Pd(0)-mediated umpolung reaction of an alkyne to achieve trans-difunctionalization is a potential synthetic methodology, but its insightful activation mechanism of Pd(0)-alkyne interaction has yet to be established. Here, a Pd(0)-π-Lewis base activation mode is proposed and investigated by combining theoretical and experimental studies. In this activation mode, the Pd(0) coordinates to the alkyne group and enhances its nucleophilicity through π-back-donation, facilitating the nucleophilic attack on the aldehyde to generate a trans-Pd(ii)-vinyl complex. Ligand-effect studies reveal that the more electron-donating one would accelerate the reaction, and the cyclization of the challenging flexible C- or O-tethered substrates has been realized. The origin of regioselectivities is also explicated by the newly proposed metal π-Lewis base activation mode.

6.
Environ Sci Technol ; 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39137068

RESUMO

Little is known about the impacts of specific chemical components on cardiovascular hospitalizations. We examined the relationships of PM2.5 chemical composition and daily hospitalizations for cardiovascular disease in 184 Chinese cities. Acute PM2.5 chemical composition exposures were linked to higher cardiovascular disease hospitalizations on the same day and the percentage change of cardiovascular admission was the highest at 1.76% (95% CI, 1.36-2.16%) per interquartile range increase in BC, followed by 1.07% (0.72-1.43%) for SO42-, 1.04% (0.63-1.46%) for NH4+, 0.99% (0.55-1.43%) for NO3-, 0.83% (0.50-1.17%) for OM, and 0.80% (0.34%-1.26%) for Cl-. Similar findings were observed for all cause-specific major cardiovascular diseases, except for heart rhythm disturbances. Short-term exposures to PM2.5 chemical composition were related to higher admissions and showed diverse impacts on major cardiovascular diseases.

7.
Zhongguo Zhong Yao Za Zhi ; 49(14): 3714-3724, 2024 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-39099346

RESUMO

Diabetic cardiomyopathy(DCM) is a chronic complication of diabetes mellitus that leads to cardiac damage in the later stages of the disease, and its pathogenesis is complex, involving metabolic disorders brought about by a variety of aberrant alterations such as endoplasmic reticulum stress, oxidative stress, inflammation, and apoptosis, defects in cardiomyocyte Ca~(2+) transporter, and myocardial fibrosis. Currently, there is a lack of specific diagnosis and treatment in the clinic. Autophagy is a highly conserved scavenging mechanism that removes proteins, damaged organelles or foreign contaminants and converts them into energy and amino acids to maintain the stability of the intracellular environment. Inhibition of autophagy can cause harmful metabolites to accumulate in the cell, while over-activation of autophagy can disrupt normal cellular structures and cause cell death. Prolonged high glucose levels disrupt cardiomyocyte autophagy levels and exacerbate the development of DCM. The protective or detrimental effects of autophagy on cells ring true with the traditional Chinese medicine theory of healthy Qi and pathogenic Qi. Autophagy in the physiological state of the removal of intracellular substances and the generation of substances beneficial to the survival of cells is the inhibition of pathogenic Qi to help the performance of healthy Qi, so the organism is healthy. In the early stages of the disease, when autophagy is impaired and incapable of removing waste substances, pathogenic Qi is prevalent; In the later stages of the disease, excessive activation of autophagy can destroy normal cells, leading to a weakening of healthy Qi. Traditional Chinese medicine has the advantage of targeting multiple sites and pathways. Studies in recent years have confirmed that traditional Chinese medicine monomers or formulas can target autophagy, promote the restoration of autophagy levels, maintain mitochondrial and endoplasmic reticulum homeostasis, and reduce oxidative stress, endoplasmic reticulum stress, inflammation, and apoptosis in order to prevent and control DCM. This study provides a review of the relationship between autophagy and DCM and the intervention of traditional Chinese medicine in autophagy for the treatment of DCM, with a view to providing new clinical ideas and methods for the treatment of DCM with traditional Chinese medicine.


Assuntos
Autofagia , Cardiomiopatias Diabéticas , Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Autofagia/efeitos dos fármacos , Cardiomiopatias Diabéticas/metabolismo , Cardiomiopatias Diabéticas/tratamento farmacológico , Cardiomiopatias Diabéticas/fisiopatologia , Humanos , Animais , Medicamentos de Ervas Chinesas/farmacologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos
8.
J Pineal Res ; 76(5): e13000, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39101387

RESUMO

Limited research has reported the association between MTNR1B gene polymorphisms and ischemic stroke (IS), and there is insufficient evidence on whether adopting a healthy lifestyle can mitigate genetic risks in this context. This study aimed to investigate the associations between MTNR1B gene variants (rs10830963 and rs1387153) and IS, examining the potential effect of gene-lifestyle interactions on IS risk. Conducted in northern China, this family-based cohort study involved 5116 initially IS-free subjects. Genotype data for rs10830963 and rs1387153 in MTNR1B were collected. Eight modifiable lifestyle factors, including body mass index (BMI), smoking, alcohol consumption, dietary habits, physical activity, sedentary time, sleep duration, and chronotype, were considered in calculating healthy lifestyle scores. Multilevel Cox models were used to examine the associations between MTNR1B variants and IS. Participants carrying the rs10830963-G and rs1387153-T alleles exhibited an elevated IS risk. Each additional rs10830963-G allele and rs1387153-T allele increased the IS risk by 36% (HR = 1.36, 95% CI, 1.12-1.65) and 32% (HR = 1.32, 95% CI, 1.09-1.60), respectively. Participants were stratified into low, medium, and high healthy lifestyle score groups (1537, 2188, and 1391 participants, respectively). Genetic-lifestyle interactions were observed for rs10830963 and rs1387153 (p for interaction < 0.001). Notably, as the healthy lifestyle score increased, the effect of MTNR1B gene variants on IS risk diminished (p for trend < 0.001). This study underscores the association between the MTNR1B gene and IS, emphasizing that adherence to a healthy lifestyle can mitigate the genetic predisposition to IS.


Assuntos
Estilo de Vida Saudável , AVC Isquêmico , Receptor MT2 de Melatonina , Humanos , Receptor MT2 de Melatonina/genética , Masculino , Feminino , Pessoa de Meia-Idade , China/epidemiologia , AVC Isquêmico/genética , AVC Isquêmico/epidemiologia , Estudos de Coortes , Polimorfismo de Nucleotídeo Único , Predisposição Genética para Doença , Adulto , Idoso
9.
Gut Microbes ; 16(1): 2390136, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39163273

RESUMO

Abdominal obesity-related metabolic syndrome (MetS) has emerged as a significant global public health issue that affects human health. Flavonoids, such as quercetin, have been reported to exert obvious anti-obesity and lipid-lowering effects in both humans and animal models. However, the precise underlying mechanism remains elusive. In this study, we investigated the potential roles of gut microbiota-bile acids (BAs) interactions in quercetin-induced anti-obesity effects and metabolic benefits. Oral administration of quercetin significantly enhanced energy metabolism through activating thermogenesis of brown adipose tissues (BAT) and browning of white adipose tissues (WAT), thus mitigating metabolic dysfunctions in an abdominal obesity-related MetS mouse model. Further mechanistic studies demonstrated that quercetin treatment substantially promoted the generation of non-12α-hydroxylated BAs (non-12OH BAs), particularly ursodeoxycholic acid (UDCA) and lithocholic acid (LCA), in serum via regulating the overall structure of gut microbiota and enriching Lactobacillus. High level of non-12OH BAs bind to Takeda G protein-coupled receptor 5 (TGR5) on adipocytes to stimulate thermogenesis. Remarkably, fecal microbiota transplantation (FMT) from quercetin-treated mice replicated the effects of quercetin on non-12OH BAs generation and energy expenditure, which suggested gut microbiota reshape and concomitant BAs regulation were responsible for the benefits on energy metabolism of quercetin in the MetS mouse model. Our findings not only highlighted the critical role of gut microbiota-BAs crosstalk in mediating quercetin-induced energy expenditure, but also enriched the pharmacological mechanisms of quercetin in ameliorating MetS-related diseases.


Assuntos
Tecido Adiposo Marrom , Ácidos e Sais Biliares , Metabolismo Energético , Microbioma Gastrointestinal , Síndrome Metabólica , Camundongos Endogâmicos C57BL , Quercetina , Termogênese , Quercetina/farmacologia , Animais , Microbioma Gastrointestinal/efeitos dos fármacos , Camundongos , Metabolismo Energético/efeitos dos fármacos , Síndrome Metabólica/metabolismo , Síndrome Metabólica/microbiologia , Síndrome Metabólica/tratamento farmacológico , Masculino , Ácidos e Sais Biliares/metabolismo , Termogênese/efeitos dos fármacos , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Branco/metabolismo , Tecido Adiposo Branco/efeitos dos fármacos , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/genética , Modelos Animais de Doenças , Transplante de Microbiota Fecal
10.
Eur Spine J ; 2024 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-39095489

RESUMO

OBJECTIVE: This study aimed to distinguish tuberculous spondylodiscitis (TS) from pyogenic spondylodiscitis (PS) based on laboratory, magnetic resonance imaging (MRI) and computed tomography (CT) findings. Further, a novel diagnostic model for differential diagnosis was developed. METHODS: We obtained MRI, CT and laboratory data from TS and PS patients. Predictive models were built using binary logistic regression analysis. The receiver operating characteristic curve was analyzed. Both internal and external validation was performed. RESULTS: A total of 81 patients with PS (n = 46) or TS (n = 35) were enrolled. All patients had etiological evidence from the focal lesion. Disc signal or height preservation, skip lesion or multi segment (involved segments ≥ 3) involvement, paravertebral calcification, massive sequestra formation, subligamentous bone destruction, bone erosion with osteosclerotic margin, higher White Blood Cell Count (WBC) and positive result of tuberculosis infection T cell spot test (T-SPOT.TB) were more prevalent in the TS group. A diagnostic model was developed and included four predictors: WBC<7.265 * (10^9/L), skip lesion or involved segments ≥ 3, massive sequestra formation and subligamentous bone destruction. The model showed good sensitivity, specificity, and total accuracy (91.4%, 95.7%, and 93.8%, respectively); the area under the receiver operating characteristic curve (AUC) was 0.981, similar to the results of internal validation using bootstrap resampling (1000 replicates) and external validation set, indicating good clinical predictive ability. CONCLUSIONS: This study develop a good diagnostic model based on both CT and MRI, as well as laboratory findings, which may help clinicians distinguish between TS and PS.

11.
Angew Chem Int Ed Engl ; : e202407682, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39103295

RESUMO

The transition metal-catalyzed asymmetric hydro-functionalization of 1,3-dienes has been well explored, but most reactions focus on electron-neutral substrates in an intermolecular manner. Here we first demonstrate that readily available 2,4-dienyl hydrazones and oximes can be efficiently utilized in the hydro-cyclization reaction under co-catalysis of a Brønsted acid and a chiral palladium complex, furnishing multifunctional dihydropyrazones and dihydroisoxazoles, respectively. Diverse substitution patterns for both types of electron-deficient diene compounds are tolerated, and corresponding heterocycles were generally constructed with moderate to excellent enantioselectivity, which can be elaborated to access products with higher molecular complexity and diversity. Control experiments and density functional theory calculations support that α-regioselective protonation of dienyl substrates by acid and concurrent π-Lewis base activation of Pd0 complex is energetically favoured in the formation of active π-allylpalladium intermediates, and an outer-sphere allylic amination or etherification mode is adopted to deliver the observed cyclized products enantioselectively.

12.
Artigo em Inglês | MEDLINE | ID: mdl-39105758

RESUMO

Substituting electrochemically active elements such as Li and Mg in P2-type layered sodium oxide is an effective strategy for developing competitive cathode materials for sodium-ion batteries. However, the lack of atomic-level understanding regarding the distribution of substitution positions complicates the comprehension of the roles of substituting atoms and the mechanism of sodium-ion intercalation. In this study, we identified the stable configurations of Na in Na0.75Ni0.3Mn0.7O2 and Na0.75Li0.15Mg0.05Ni0.1Mn0.7O2 materials using the site exclusion method. Through simulating the complete charging process for both materials, the structure evolution of the cathodes during the cycling and the impact of the partial substitution of Ni elements by Li and Mg atoms were comprehensively elucidated. Our findings revealed that Mg atoms effectively regulate the distribution of forces within the materials, essentially serving as supportive pillars within the cathode. Meanwhile, Li atoms efficiently mitigated electron localization, consequently diminishing volume fluctuations during the charging process. More importantly, the substitution with Li and Mg atoms could synergistically reduce the interaction between transition metals and sodium ions, thereby reducing the diffusion energy barrier of Na ions. This study not only enhances the comprehension of substituted metal atoms in P2 layered oxides but also offers new insights for the development of sodium-ion cathode materials.

13.
World J Psychiatry ; 14(8): 1267-1284, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39165557

RESUMO

BACKGROUND: Overweight/obesity combined with depression among children and adolescents (ODCA) is a global concern. The bidirectional relationship between depression and overweight/obesity often leads to their comorbidity. Childhood and adolescence represent critical periods for physical and psychological development, during which the comorbidity of overweight/obesity and depression may increase the risk of adverse health outcomes. AIM: To evaluate the relationship between ODCA, we conduct a bibliometric analysis to aid in formulating prevention and treatment strategies. METHODS: From 2004 to 2023, articles related to ODCA were selected using the Science Citation Index Expanded from the Web of Science Core Collection. Bibliometric analysis of relevant publications, including countries/regions, institutions, authors, journals, references, and keywords, was conducted using the online bibliometric analysis platforms, CiteSpace, VOSviewer, and bibliometrix. RESULTS: Between 2004 and 2023, a total of 1573 articles were published on ODCA. The United States has made leading contributions in this field, with Harvard University emerging as the leading contributor in terms of research output, and Tanofsky being the most prolific author. The J Adolescent Health has shown significant activity in this domain. Based on the results of the keyword and reference analyses, inequality, adverse childhood experiences, and comorbidities have become hot topics in ODCA. Moreover, the impact of balanced-related behavior and exploration of the biological mechanisms, including the potential role of key adipocytokines and lipokines, as well as inflammation in ODCA, have emerged as frontier topics. CONCLUSION: The trend of a significant increase in ODCA publications is expected to continue. The research findings will contribute to elucidating the pathogenic mechanisms of ODCA and its prevention and treatment.

14.
Mucosal Immunol ; 2024 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-39159846

RESUMO

The Helper ILC contains various functional subsets, such as ILC1, ILC2, ILC3 and LTi cells, mediating the immune responses against viruses, parasites, and extracellular bacteria, respectively. Among them, LTi cells are also crucial for the formation of peripheral lymphoid tissues, such as lymph nodes. Our research, along with others', indicates a high proportion of LTi cells in the fetal ILC pool, which significantly decreases after birth. Conversely, the proportion of non-LTi ILCs increases postnatally, corresponding to the need for LTi cells to mediate lymphoid tissue formation during fetal stages and other ILC subsets to combat diverse pathogen infections postnatally. However, the regulatory mechanism for this transition remains unclear. In this study, we observed a preference for fetal ILC progenitors to differentiate into LTi cells, while postnatal bone marrow ILC progenitors preferentially differentiate into non-LTi ILCs. Particularly, this differentiation shift occurs within the first week after birth in mice. Further analysis revealed that adult ILC progenitors exhibit stronger activation of the Notch signaling pathway compared to fetal counterparts, accompanied by elevated Gata3 expression and decreased Rorc expression, leading to a transition from fetal LTi cell-dominant states to adult non LTi ILC-dominant states. This study suggests that the body can regulate ILC development by modulating the activation level of the Notch signaling pathway, thereby acquiring different ILC subsets to accommodate the varying demands within the body at different developmental stages.

15.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 41(8): 1010-1015, 2024 Aug 10.
Artigo em Chinês | MEDLINE | ID: mdl-39097288

RESUMO

DNA methylation is an important epigenetic regulatory mechanism which plays a crucial role in cell differentiation and development. Its function is closely related to DNA methyltransferase 3 alpha (DNMT3A), which can affect gene expression and stem cell differentiation. The mutation rate of the DNMT3A gene is relatively high in Acute myeloid leukemia (AML), but its type and pathogenic mechanism are not yet clear. Further research on DNMT3A may help to identify its pathogenic targets and provide a basis for precise treatment of AML. This article has provided a review for the research progress on the expression of the DNMT3A gene in AML.


Assuntos
DNA (Citosina-5-)-Metiltransferases , DNA Metiltransferase 3A , Leucemia Mieloide Aguda , DNA (Citosina-5-)-Metiltransferases/genética , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/enzimologia , Metilação de DNA , Regulação Leucêmica da Expressão Gênica
16.
Phys Chem Chem Phys ; 26(32): 21568-21574, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39082369

RESUMO

Structural analyses using Raman optical activity (ROA) spectroscopy conventionally rely on vibrational signals in the fingerprint region ranging from 100 to 1800 cm-1. Use of deuterium labelling to observe ROA signals in the C-D stretching region provides additional information about a local structure of large molecular systems. So far, the potential of C-D stretching ROA signals for structural analysis has rarely been explored. In the present work, we synthesized model deuterated glucose monosaccharides and studied their ROA properties by employing molecular dynamics and density functional theory to interpret the spectra. A good agreement between the simulated and experimental spectra is achieved when the proper conformer ratios are considered. This shows the usefulness of ROA spectroscopy assisted by deuterium labelling for stereochemical and conformational analysis.

17.
World Neurosurg ; 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39033806

RESUMO

OBJECTIVE: Some patients with intracranial aneurysms (IAs) cannot undergo three-dimensional computed tomography angiography (3D-CTA) or digital subtraction angiography due to contraindications to contrast agents or radiation. Time-of-flight magnetic resonance angiography (TOF-MRA) offers a contrast-free alternative but lacks cranial bone detail critical for surgical planning. This study evaluates the feasibility of using 3D Slicer to fuse TOF-MRA with thin-section CT images to generate synthetic images resembling CTA for surgical clipping planning. METHODS: This prospective study included 22 patients with unruptured IAs and 8 with ruptured IAs undergoing aneurysm clipping surgery (≥3 mm). TOF-MRA and CT/3D-CTA scans were fused using 3D Slicer. Neuroradiologists and neurosurgeons independently assessed 3D-CTA and synthetic TOF-MRA-CT images for aneurysm detection rates, morphology, and dimensions. Evaluation metrics included dice similarity coefficient and 95% Hausdorff distance. RESULTS: Evaluation of aneurysm detection rates, morphology, and dimensions showed no significant differences between synthetic TOF-MRA-CT fusion images and 3D-CTA (all P > 0.05). Neuroradiologist assessments revealed strong concordance in aneurysm morphology between synthetic TOF-MRA-CT fusion images and 3D-CTA (κ = 0.867, P < 0.001). The dice similarity coefficient (0.937 ± 0.012) and Hausdorff distance (4.54 ± 0.26) indicated a high degree of image overlap between synthetic TOF-MRA-CT fusion images and 3D-CTA. Surgeons rated the consistency of aneurysm morphology between synthetic TOF-MRA-CT fusion images and intraoperative findings as strongly concordant (κ = 0.873, P < 0.001). CONCLUSIONS: Synthetic TOF-MRA-CT fusion images closely match 3D-CTA for ≥3 mm aneurysms, demonstrating comparable diagnostic and surgical clipping planning effectiveness. They represent a promising alternative for personalized preoperative planning, particularly when contrast agents are contraindicated.

18.
Quant Imaging Med Surg ; 14(7): 4464-4474, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39022221

RESUMO

Background: Parkinson disease (PD) and multiple system atrophy (MSA) are neurodegenerative disorders characterized by the accumulation of alpha-synuclein. Distinguishing between these conditions remains a significant challenge. This study thus employed quantitative susceptibility mapping (QSM) to evaluate subcortical iron deposition and its clinical implications in patients with PD or MSA and a group of healthy controls (HCs). Methods: The study included 26 patients with MSA, 40 patients with PD, and 35 HCs. We used magnetic resonance imaging (MRI)-based QSM to measure iron accumulation in the substantia nigra pars compacta (SNc), substantia nigra pars reticulata (SNr), and globus pallidus internus (GPi). We assessed differences between groups, examined correlations with clinical scores, and conducted receiver operating characteristic (ROC) curve analysis. Results: Compared to those with PD, patients with MSA showed more severe motor and nonmotor impairment. QSM analysis indicated a significant increase in iron levels in the SNc, SNr, and GPi regions in patient groups compared to HCs. In patients with MSA, a notable positive correlation was found between SNc QSM values and Non-Motor Symptoms Scale scores (r=0.4; P=0.043). In patients with PD, a positive association was observed between iron levels in the SNc and Unified Parkinson's Disease Rating Scale Part III (UPDRS-III) (r=0.395; P=0.012) and Hamilton Depression Rating Scale scores (r=0.313; P=0.049). Furthermore, iron content in the GPi inversely correlated with rapid-eye movement sleep behavior disorder questionnaire-Hong Kong scores (r=-0.342; P=0.031). The SNr region demonstrated the best ability to discriminate between MSA and PD with an area under the curve (AUC) of 0.67, followed by the GPi (AUC =0.64) and SNc (AUC =0.57). Conclusions: QSM effectively quantified subcortical iron deposition in the PD, MSA, and HC groups. The correlations found between iron levels and clinical manifestations provide insights into the pathophysiological processes of these disorders, highlighting the potential of QSM as a diagnostic tool for differentiation.

19.
Anim Nutr ; 18: 17-26, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39022774

RESUMO

The transition period for dairy cows usually refers to the 3 weeks pre-calving to the 3 weeks post-calving. During this period, dairy cows undergo metabolic and physiological adaptations because of their susceptibility to metabolic and infectious diseases. Poor feeding management under these circumstances may adversely affect the health and subsequent production performance of the cows. Owing to long-term adaptation and evolution, the rumen has become a unique ecosystem inhabited by a complex microbial community closely associated with its natural host. Dietary components are metabolized by the rumen microbiota, and volatile fatty acids and microbial protein products can be used as precursor substances for synthesizing meat and milk components. The successful transition of perinatal dairy cows includes changes in diet, physiology, and the rumen microbiota. Rumen microbial profiles have been confirmed to be heritable and repairable; however, adverse circumstances affect rumen microbial composition, host digestion and metabolism, as well as postpartum production traits of dairy cows for a certain period. Preliminary evidence indicates a close relationship between the rumen microbiota and animal performance. Therefore, changes in rumen microbes during the transition period and the intrinsic links between the microbiota and host postpartum phenotypic traits need to be better understood to optimize production performance in ruminants.

20.
IEEE Trans Image Process ; 33: 4202-4214, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39008382

RESUMO

Both Convolutional Neural Networks (CNNs) and Transformers have shown great success in semantic segmentation tasks. Efforts have been made to integrate CNNs with Transformer models to capture both local and global context interactions. However, there is still room for enhancement, particularly when considering constraints on computational resources. In this paper, we introduce HAFormer, a model that combines the hierarchical features extraction ability of CNNs with the global dependency modeling capability of Transformers to tackle lightweight semantic segmentation challenges. Specifically, we design a Hierarchy-Aware Pixel-Excitation (HAPE) module for adaptive multi-scale local feature extraction. During the global perception modeling, we devise an Efficient Transformer (ET) module streamlining the quadratic calculations associated with traditional Transformers. Moreover, a correlation-weighted Fusion (cwF) module selectively merges diverse feature representations, significantly enhancing predictive accuracy. HAFormer achieves high performance with minimal computational overhead and compact model size, achieving 74.2% mIoU on Cityscapes and 71.1% mIoU on CamVid test datasets, with frame rates of 105FPS and 118FPS on a single 2080Ti GPU. The source codes are available at https://github.com/XU-GITHUB-curry/HAFormer.

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