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1.
Nature ; 629(8014): 1091-1099, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38750363

RESUMO

The baobab trees (genus Adansonia) have attracted tremendous attention because of their striking shape and distinctive relationships with fauna1. These spectacular trees have also influenced human culture, inspiring innumerable arts, folklore and traditions. Here we sequenced genomes of all eight extant baobab species and argue that Madagascar should be considered the centre of origin for the extant lineages, a key issue in their evolutionary history2,3. Integrated genomic and ecological analyses revealed the reticulate evolution of baobabs, which eventually led to the species diversity seen today. Past population dynamics of Malagasy baobabs may have been influenced by both interspecific competition and the geological history of the island, especially changes in local sea levels. We propose that further attention should be paid to the conservation status of Malagasy baobabs, especially of Adansonia suarezensis and Adansonia grandidieri, and that intensive monitoring of populations of Adansonia za is required, given its propensity for negatively impacting the critically endangered Adansonia perrieri.


Assuntos
Adansonia , Filogenia , Adansonia/classificação , Adansonia/genética , Biodiversidade , Conservação dos Recursos Naturais , Ecologia , Espécies em Perigo de Extinção , Evolução Molecular , Genoma de Planta/genética , Madagáscar , Dinâmica Populacional , Elevação do Nível do Mar
2.
Cell Mol Life Sci ; 81(1): 123, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38459149

RESUMO

Maintaining genomic stability is a prerequisite for proliferating NPCs to ensure genetic fidelity. Though histone arginine methylation has been shown to play important roles in safeguarding genomic stability, the underlying mechanism during brain development is not fully understood. Protein arginine N-methyltransferase 5 (PRMT5) is a type II protein arginine methyltransferase that plays a role in transcriptional regulation. Here, we identify PRMT5 as a key regulator of DNA repair in response to double-strand breaks (DSBs) during NPC proliferation. Prmt5F/F; Emx1-Cre (cKO-Emx1) mice show a distinctive microcephaly phenotype, with partial loss of the dorsal medial cerebral cortex and complete loss of the corpus callosum and hippocampus. This phenotype is resulted from DSBs accumulation in the medial dorsal cortex followed by cell apoptosis. Both RNA sequencing and in vitro DNA repair analyses reveal that PRMT5 is required for DNA homologous recombination (HR) repair. PRMT5 specifically catalyzes H3R2me2s in proliferating NPCs in the developing mouse brain to enhance HR-related gene expression during DNA repair. Finally, overexpression of BRCA1 significantly rescues DSBs accumulation and cell apoptosis in PRMT5-deficient NSCs. Taken together, our results show that PRMT5 maintains genomic stability by regulating histone arginine methylation in proliferating NPCs.


Assuntos
Células-Tronco Neurais , Reparo de DNA por Recombinação , Animais , Camundongos , Arginina/metabolismo , Reparo do DNA , Instabilidade Genômica , Genômica , Histonas/genética , Histonas/metabolismo , Células-Tronco Neurais/metabolismo , Proteína-Arginina N-Metiltransferases/genética , Proteína-Arginina N-Metiltransferases/metabolismo
3.
BMC Genomics ; 25(1): 539, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38822248

RESUMO

Squamous promoter binding protein-like (SPL) genes encode plant-specific transcription factors (TFs) that play essential roles in modulating plant growth, development, and stress response. Pea (Pisum sativum L.) is a coarse grain crop of great importance in food production, biodiversity conservation and molecular genetic research, providing genetic information and nutritional resources for improving agricultural production and promoting human health. However, only limited researches on the structure and functions of SPL genes exist in pea (PsSPLs). In this study, we identified 22 PsSPLs and conducted a genome-wide analysis of their physical characteristics, chromosome distribution, gene structure, phylogenetic evolution and gene expression patterns. As a result, the PsSPLs were unevenly distributed on the seven chromosomes of pea and harbored the SBP domain, which is composed of approximately 76 amino acid residues. The phylogenetic analysis revealed that the PsSPLs clustered into eight subfamilies and showed high homology with SPL genes in soybean. Further analysis showed the presence of segmental duplications in the PsSPLs. The expression patterns of 22 PsSPLs at different tissues, developmental stages and under various stimulus conditions were evaluated by qRT-PCR method. It was found that the expression patterns of PsSPLs from the same subfamily were similar in different tissues, the transcripts of most PsSPLs reached the maximum peak value at 14 days after anthesis in the pod. Abiotic stresses can cause significantly up-regulated PsSPL19 expression with spatiotemporal specificity, in addition, four plant hormones can cause the up-regulated expression of most PsSPLs including PsSPL19 in a time-dependent manner. Therefore, PsSPL19 could be a key candidate gene for signal transduction during pea growth and development, pod formation, abiotic stress and plant hormone response. Our findings should provide insights for the elucidating of development regulation mechanism and breeding for resistance to abiotic stress pea.


Assuntos
Regulação da Expressão Gênica de Plantas , Filogenia , Pisum sativum , Proteínas de Plantas , Estresse Fisiológico , Fatores de Transcrição , Pisum sativum/genética , Pisum sativum/crescimento & desenvolvimento , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Genoma de Planta , Família Multigênica , Perfilação da Expressão Gênica , Cromossomos de Plantas/genética
4.
Front Neuroendocrinol ; 70: 101082, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37414372

RESUMO

Ectopic fat, defined as a specific organ or compartment with the accumulation of fat tissue surrounding organs, is highly associated with obesity which has been identified as a risk factor for cognitive impairment and dementia. However, the relationship between ectopic fat and changes in brain structure or cognition is yet to be elucidated. Here, we investigated the effects of ectopic fat on brain structure and cognitive function via systemic review and meta-analysis. A total of 21 studies were included from electronic databases up to July 9, 2022. We found ectopic fat was associated with decreased total brain volumeand increased lateral ventricle volume. In addition, ectopic was associated with decreased cognitive scores and negatively correlated with cognitive function. More specifically, dementia development were correlated with increased levels of visceral fat. Overall, our data suggested that increased ectopic fat was associated with prominent structural changes in the brain and cognitive decline, an effect driven mainly by increases in visceral fat, while subcutaneous fat may be protective. Our results suggest that patients with increased visceral fat are at risk of developing cognitive impairment and, therefore, represent a subset of population in whom appropriate and timely preventive measures could be implemented.


Assuntos
Disfunção Cognitiva , Demência , Humanos , Cognição , Tecido Adiposo , Encéfalo/diagnóstico por imagem , Disfunção Cognitiva/etiologia , Demência/complicações
5.
Anal Chem ; 96(14): 5499-5508, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38547315

RESUMO

Characterizing the profiles of proteome and metabolome at the single-cell level is of great significance in single-cell multiomic studies. Herein, we proposed a novel strategy called one-shot single-cell proteome and metabolome analysis (scPMA) to acquire the proteome and metabolome information in a single-cell individual in one injection of LC-MS/MS analysis. Based on the scPMA strategy, a total workflow was developed to achieve the single-cell capture, nanoliter-scale sample pretreatment, one-shot LC injection and separation of the enzyme-digested peptides and metabolites, and dual-zone MS/MS detection for proteome and metabolome profiling. Benefiting from the scPMA strategy, we realized dual-omic analysis of single tumor cells, including A549, HeLa, and HepG2 cells with 816, 578, and 293 protein groups and 72, 91, and 148 metabolites quantified on average. A single-cell perspective experiment for investigating the doxorubicin-induced antitumor effects in both the proteome and metabolome aspects was also performed.


Assuntos
Proteoma , Espectrometria de Massas em Tandem , Humanos , Proteoma/metabolismo , Cromatografia Líquida , Metaboloma , Células HeLa
6.
Mass Spectrom Rev ; 42(1): 432-452, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-34486155

RESUMO

Lipids, serving as the structural components of cellular membranes, energy storage, and signaling molecules, play the essential and multiple roles in biological functions of mammals. Mass spectrometry (MS) is widely accepted as the first choice for lipid analysis, offering good performance in sensitivity, accuracy, and structural characterization. However, the untargeted qualitative profiling and absolute quantitation of lipids are still challenged by great structural diversity and high structural similarity. In recent decade, chemical derivatization mainly targeting carboxyl group and carbon-carbon double bond of lipids have been developed for lipidomic analysis with diverse advantages: (i) offering more characteristic structural information; (ii) improving the analytical performance, including chromatographic separation and MS sensitivity; (iii) providing one-to-one chemical isotope labeling internal standards based on the isotope derivatization regent in quantitative analysis. Moreover, the chemical derivatization strategy has shown great potential in combination with ion mobility mass spectrometry and ambient mass spectrometry. Herein, we summarized the current states and advances in chemical derivatization-assisted MS techniques for lipidomic analysis, and their strengths and challenges are also given. In summary, the chemical derivatization-based lipidomic approach has become a promising and reliable technique for the analysis of lipidome in complex biological samples.


Assuntos
Espectrometria de Mobilidade Iônica , Lipidômica , Animais , Espectrometria de Massas/métodos , Lipídeos/análise , Carbono , Mamíferos
7.
Chemistry ; : e202401727, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38979891

RESUMO

The development of innovative synthetic strategies to create functional polycaprolactones is highly demanded for advanced material applications. In this contribution, we reported a facile synthetic strategy to prepare a class of CL-based monomers (R-TO) derived from epoxides. They readily polymerize via well-controlled ring-opening polymerization (ROP) to afford a series of polyesters P(R-TO) with high molecular weight (Mn up to 350 kDa). Sequential addition copolymerization of MTO and L-lactide (L-LA) allowed to access of a series of ABA triblock copolymers with composition-dependent mechanical properties. Notably, P(L-LA)100-b-P(MTO)500-b-P(L-LA)100 containing the amorphous P(MTO) segment as a soft midblock and crystalline P(L-LA) domain as hard end block behaved as an excellent thermoplastic elastomer (TPE) with high elongation at break (1438 ± 204%), tensile strength (23.5 ± 1.7 MPa), and outstanding elastic recovery (>88%).

8.
BMC Cancer ; 24(1): 404, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561648

RESUMO

BACKGROUND: Accurate microsatellite instability (MSI) testing is essential for identifying gastric cancer (GC) patients eligible for immunotherapy. We aimed to develop and validate a CT-based radiomics signature to predict MSI and immunotherapy outcomes in GC. METHODS: This retrospective multicohort study included a total of 457 GC patients from two independent medical centers in China and The Cancer Imaging Archive (TCIA) databases. The primary cohort (n = 201, center 1, 2017-2022), was used for signature development via Least Absolute Shrinkage and Selection Operator (LASSO) and logistic regression analysis. Two independent immunotherapy cohorts, one from center 1 (n = 184, 2018-2021) and another from center 2 (n = 43, 2020-2021), were utilized to assess the signature's association with immunotherapy response and survival. Diagnostic efficiency was evaluated using the area under the receiver operating characteristic curve (AUC), and survival outcomes were analyzed via the Kaplan-Meier method. The TCIA cohort (n = 29) was included to evaluate the immune infiltration landscape of the radiomics signature subgroups using both CT images and mRNA sequencing data. RESULTS: Nine radiomics features were identified for signature development, exhibiting excellent discriminative performance in both the training (AUC: 0.851, 95%CI: 0.782, 0.919) and validation cohorts (AUC: 0.816, 95%CI: 0.706, 0.926). The radscore, calculated using the signature, demonstrated strong predictive abilities for objective response in immunotherapy cohorts (AUC: 0.734, 95%CI: 0.662, 0.806; AUC: 0.724, 95%CI: 0.572, 0.877). Additionally, the radscore showed a significant association with PFS and OS, with GC patients with a low radscore experiencing a significant survival benefit from immunotherapy. Immune infiltration analysis revealed significantly higher levels of CD8 + T cells, activated CD4 + B cells, and TNFRSF18 expression in the low radscore group, while the high radscore group exhibited higher levels of T cells regulatory and HHLA2 expression. CONCLUSION: This study developed a robust radiomics signature with the potential to serve as a non-invasive biomarker for GC's MSI status and immunotherapy response, demonstrating notable links to post-immunotherapy PFS and OS. Additionally, distinct immune profiles were observed between low and high radscore groups, highlighting their potential clinical implications.


Assuntos
Radiômica , Neoplasias Gástricas , Humanos , Estudos de Coortes , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/genética , Neoplasias Gástricas/terapia , Estudos Retrospectivos , Instabilidade de Microssatélites , Imunoterapia , Tomografia Computadorizada por Raios X , Imunoglobulinas
9.
Eur Radiol ; 34(2): 1280-1291, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37589900

RESUMO

OBJECTIVES: To develop a CT-based radiomics model for preoperative prediction of lymph node (LN) metastasis in perihilar cholangiocarcinoma (pCCA). METHODS: The study enrolled consecutive pCCA patients from three independent Chinese medical centers. The Boruta algorithm was applied to build the radiomics signature for the primary tumor and LN. The k-means algorithm was employed to cluster the selected LNs based on the radiomics signature LN. Support vector machines were used to construct the prediction models. The diagnostic efficiency was measured by the area under the receiver operating characteristic curve (AUC). The optimal model was evaluated in terms of calibration, clinical usefulness, and prognostic value. RESULTS: A total of 214 patients were included in the study (mean age: 61.6 years ± 9.4; 130 male). The selected LNs were classified into two clusters, which were significantly correlated with LN metastasis in all cohorts (p < 0.001). The model incorporated the clinical risk factors, radiomics signature primary tumor, and the LN cluster obtained the best discrimination, with AUC values of 0.981 (95% CI: 0.962-1), 0.896 (95% CI: 0.810-0.982), and 0.865 (95% CI: 0.768-0.961) in the training, internal validation, and external validation cohorts, respectively. High-risk patients predicted by the optimal model had shorter overall survival than low-risk patients (median, 13.7 vs. 27.3 months, p < 0.001). CONCLUSIONS: The study proposed a radiomics model with good performance to predict LN metastasis in pCCA. As a noninvasive preoperative prediction tool, this model may help in patient risk stratification and personalized treatment. CLINICAL RELEVANCE STATEMENT: A CT-based radiomics model accurately predicts lymph node metastasis in perihilar cholangiocarcinoma patients. This noninvasive preoperative tool can aid in patient risk stratification and personalized treatment, potentially improving patient outcomes. KEY POINTS: • The radiomics model based on contrast-enhanced CT is a useful tool for preoperative prediction of lymph node metastasis in perihilar cholangiocarcinoma. • Radiomics features extracted from lymph nodes show great potential for predicting lymph node metastasis. • The study is the first to identify a lymph node phenotype with a high probability of metastasis based on radiomics.


Assuntos
Neoplasias dos Ductos Biliares , Tumor de Klatskin , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Linfática/patologia , Tumor de Klatskin/diagnóstico por imagem , Tumor de Klatskin/cirurgia , Radiômica , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Linfonodos/patologia , Neoplasias dos Ductos Biliares/diagnóstico por imagem , Neoplasias dos Ductos Biliares/cirurgia , Neoplasias dos Ductos Biliares/patologia
10.
Inorg Chem ; 63(15): 6928-6937, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38571457

RESUMO

Four Co(II)-based metal-organic frameworks (MOFs) were constructed by a mixed ligand strategy under solvothermal conditions. The controllable modification of the bridging groups in the secondary building units was realized by changing the anions in MOFs 1-3. The MOF 4 with 3D framework structure was obtained by regulating the solvent ratio following the synthesis process of MOF 3. Furthermore, the MOFs 1-4 exhibited efficient photocatalytic activity for the degradation of malachite green (MG) dye without any photosensitizer or cocatalyst under a low-energy light source, the decolorization ratio of MG all reached more than 96.0% within 60 min, and maximal degradation was obtained to be 99.4% (MOF 4). The recycling experiments showed that the degradation rate of MG was still higher than 91% after 10 cycles. In the MOF 4 as representation, the photocatalytic process was explored systematically. The possible mechanism of catalytic degradation was discussed, which proved the existence of efficient oxidation active factors (•O2-, •OH, and h+). The possible intermediates and degradation pathways were investigated based on high-performance liquid chromatography tandem mass spectrometry. Additionally, MOFs 1-4 also exhibited excellent photocatalytic activity for the degradation of methylene blue, methyl violet, rhodamine B, and basic red 9.

11.
Inorg Chem ; 63(20): 9109-9118, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38711379

RESUMO

Two two-dimensional (2D) layered metal-organic frameworks (MOFs), namely, {[Yb(L)(H2O)2NO3]·2H2O}n (Yb-MOF) and [Er(L)(H2O)3Cl]n (Er-MOF) (H2L = 5-((6H-purin-6-yl)amino)isophthalic acid), were constructed by a solvothermal method and characterized. The catalytic performance study showed that the Yb-MOF could efficiently catalyze the oxidation of sulfides to sulfoxides under 15 W light-emitting diode (LED) blue light irradiation. Electron paramagnetic resonance spectroscopy and free-radical trapping experiments demonstrated that the photocatalytic reaction process involved •O2-, and the corresponding mechanism was proposed. Moreover, Er-MOF exhibited good catalytic efficiency and excellent substrate tolerance in the cycloaddition reaction of CO2, and the reaction conditions were mild. After 5 cycles, the catalytic activities of two MOFs did not significantly decrease, and the framework structures remained unchanged. Therefore, the Yb-MOF and Er-MOF were considered efficient and stable heterogeneous catalysts.

12.
Acta Pharmacol Sin ; 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886550

RESUMO

Urolithin A (UroA), a dietary phytochemical, is produced by gut bacteria from fruits rich in natural polyphenols ellagitannins (ETs). The efficiency of ETs metabolism to UroA in humans depends on gut microbiota. UroA has shown a variety of pharmacological activities. In this study we investigated the effects of UroA on atherosclerotic lesion development and stability. Apolipoprotein E-deficient (ApoE-/-) mice were fed a high-fat and high-cholesterol diet for 3 months to establish atherosclerosis model. Meanwhile the mice were administered UroA (50 mg·kg-1·d-1, i.g.). We showed that UroA administration significantly decreased diet-induced atherosclerotic lesions in brachiocephalic arteries, macrophage content in plaques, expression of endothelial adhesion molecules, intraplaque hemorrhage and size of necrotic core, while increased the expression of smooth muscle actin and the thickness of fibrous cap, implying features of plaque stabilization. The underlying mechanisms were elucidated using TNF-α-stimulated human endothelial cells. Pretreatment with UroA (10, 25, 50 µM) dose-dependently inhibited TNF-α-induced endothelial cell activation and monocyte adhesion. However, the anti-inflammatory effects of UroA in TNF-α-stimulated human umbilical vein endothelial cells (HUVECs) were independent of NF-κB p65 pathway. We conducted RNA-sequencing profiling analysis to identify the differential expression of genes (DEGs) associated with vascular function, inflammatory responses, cell adhesion and thrombosis in UroA-pretreated HUVECs. Human disease enrichment analysis revealed that the DEGs were significantly correlated with cardiovascular diseases. We demonstrated that UroA pretreatment mitigated endothelial inflammation by promoting NO production and decreasing YAP/TAZ protein expression and TEAD transcriptional activity in TNF-α-stimulated HUVECs. On the other hand, we found that UroA administration modulated the transcription and cleavage of lipogenic transcription factors SREBP1/2 in the liver to ameliorate cholesterol metabolism in ApoE-/- mice. This study provides an experimental basis for new dietary therapeutic option to prevent atherosclerosis.

13.
BMC Med Imaging ; 24(1): 57, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38443826

RESUMO

BACKGROUND: The morphological information of the pulmonary vein (PV) and left atrium (LA) is of immense clinical importance for effective atrial fibrillation ablation. The aim of this study is to examine the consistency in different LA diameter measurement techniques. METHODS: Retrospective imaging data from 87 patients diagnosed with PV computed tomography angiography were included. The patients consisted of 50 males and 37 females, with an average age of (60.74 ± 8.70) years. Two physicians independently measured the anteroposterior diameter, long diameter, and transverse diameter of the LA using six different methods. Additionally, we recorded the post-processing time of the images. Physician 1 conducted measurements twice with a one-month interval between the measurements to assess intra-rater reliability. Using the intraclass correlation coefficient (ICC), the consistency of each LA diameter measurement by the two physicians was evaluated. We compared the differences in the LA diameter and the time consumed for measurements using different methods. This was done by employing the rank sum test of a randomized block design (Friedman M test) and the q test for pairwise comparisons among multiple relevant samples. RESULTS: (1) The consistency of the measured LA diameter by the two physicians was strong or very strong. (2) There were statistical differences in the anteroposterior diameter, long diameter, and transverse diameter of LA assessed using different methods (χ2 = 222.28, 32.74, 293.83, P < 0.001). (3) Different methods for measuring the diameters of LA required different amounts of time (χ2 = 333.10, P < 0.001). CONCLUSION: The results of left atrium (LA) diameter measurements conducted by different physicians were found to be reliable. However, the LA diameters obtained through various techniques exhibited variations. It was observed that measuring LA long diameters using only the VR (volume rendering) picture was the most clinically applicable method.


Assuntos
Fibrilação Atrial , Átrios do Coração , Feminino , Masculino , Humanos , Pessoa de Meia-Idade , Idoso , Reprodutibilidade dos Testes , Estudos Retrospectivos , Átrios do Coração/diagnóstico por imagem , Fibrilação Atrial/diagnóstico por imagem , Angiografia
14.
BMC Ophthalmol ; 24(1): 94, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429639

RESUMO

BACKGROUND: Most studies had shown a linear relationship between serum albumin (sALB) and the prevalence of diabetic retinopathy (DR). Thus, the purpose of this study is to investigate whether their relationship is non-linear. METHODS: We included 426 patients with type 2 diabetes who were hospitalized in Guangdong Provincial People's Hospital from December 2017 to November 2018. The outcome was the prevalence of DR. A two-piecewise logistics regression model was performed to identify the non-linear relationship between sALB and the prevalence of DR. The inflection point was calculated to determine the saturation effect through the maximum likelihood ratio and a recursive algorithm. RESULTS: DR was diagnosed in 167 of 426 type 2 diabetic patients. The relationship between sALB and DR was nonlinear. When sALB was less than 38.10 g/L, a significant negative association was observed (OR = 0.82; 95% CI, 0.72-0.94; P = 0.0037), while no significant association was observed when sALB was greater than 38.10 g/L (OR = 1.12; 95% CI, 0.92-1.35; P = 0.2637). CONCLUSIONS: The relationship between sALB and the prevalence of DR is non-linear. sALB is negatively associated with the prevalence of DR when sALB is less than 38.10 g/L. Our findings need to be confirmed by further prospective research.


Assuntos
Diabetes Mellitus Tipo 2 , Retinopatia Diabética , Humanos , Algoritmos , Estudos Transversais , Diabetes Mellitus Tipo 2/complicações , Retinopatia Diabética/sangue , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/metabolismo , Albumina Sérica
15.
BMC Anesthesiol ; 24(1): 174, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38745175

RESUMO

BACKGROUND: Compared to midazolam, remimazolam has a faster onset and offset of hypnotic effect, as well as cardiorespiratory stability, this study aims to determine the 90% effective dose (ED90) of remimazolam to inhibit responses to insertion of a duodenoscope during endoscopic retrograde cholangiopancreatography (ERCP). METHODS: A dose-response study was carried out undergoing ERCP who received remimazolam-alfentanil anesthesia using 10 µg/kg of alfentanil between September 2021 and November 2021. The initial dose of remimazolam was 0.2 mg/kg. The dose was then decided based on the responses of earlier patients by exploiting the sequential ascend and descend according to a 9: 1 biased coin design. Upon failure, the dose of remimazolam was increased by 0.025 mg/kg in the next patient. When the insertion was successful, the succeeding patient was randomized to an identical dose or a dose that was lower by 0.025 mg/kg.The ED90 of remimazolam for inhibiting responses to the insertion of a duodenoscope during ERCP was calculated. Adverse events and complications of remimazolam were recorded. RESULTS: A total of 55 elderly patients (age > 65) were included in the study. 45 successfully anesthetized patients, and 10 unsuccessfully. The ED90 of remimazolam was 0.300 mg/kg (95% CI = 0.287-0.320). ED95 was 0.315 (95% CI = 0.312-0.323) and ED99 was 0.323 (95% CI = 0.323-0.325). Among the patients, 9 patients developed hypotension, 2 patients developed bradycardia and 1 patient developed tachycardia, and hypoxia occurred in 2 patients. CONCLUSIONS: A loading dose of 0.300 mg / kg of remimazolam for elderly patients undergoing ERCP can safely, effectively, and quickly induce patients to fall asleep and inhibit responses to the insertion of a duodenoscope. TRIAL REGISTRATION: The study protocol was registered at the website ClinicalTrials.gov on 22/09/2021(NCT05053763).


Assuntos
Colangiopancreatografia Retrógrada Endoscópica , Relação Dose-Resposta a Droga , Duodenoscópios , Hipnóticos e Sedativos , Humanos , Colangiopancreatografia Retrógrada Endoscópica/métodos , Masculino , Feminino , Hipnóticos e Sedativos/administração & dosagem , Idoso , Alfentanil/administração & dosagem , Pessoa de Meia-Idade , Benzodiazepinas/administração & dosagem
16.
J Asian Nat Prod Res ; 26(2): 189-194, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37882670

RESUMO

Two new baccharane triterpenes, 17,24-epoxy-23-en-baccharan-3-one (1) and 17,24(S)-epoxy-25-en-21-hydroxy-baccharan-3-one (2) were isolated from Rhus chinensis Mill. The structures were established on the basis of UV, IR, HR-ESI-MS, 1D and 2D NMR spectroscopy and X-ray diffraction analysis.


Assuntos
Rhus , Triterpenos , Triterpenos Pentacíclicos , Rhus/química , Triterpenos/farmacologia , Triterpenos/química , Extratos Vegetais , Espectroscopia de Ressonância Magnética , Estrutura Molecular
17.
Nano Lett ; 23(18): 8808-8815, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37459604

RESUMO

The development of advanced electrical equipment necessitates polymer dielectrics with a higher electric strength. Unfortunately, this bottleneck problem has yet to be solved because current material modification methods do not allow direct control of deep traps. Here, we propose a method for directly passivating deep traps. Measurements of nanoscale microregion charge characteristics and trap parameters reveal a significant reduction in the number of deep traps. The resulting polymer dielectric has an impressively high electrical strength, less surface charge accumulation, and a significantly increased flashover voltage and breakdown strength. In addition, the energy storage density is increased without sacrificing the charge-discharge efficiency. This reveals a new approach to increasing the energy storage density by reducing the trap energy levels at the electrode-dielectric interface. We further calculated and analyzed the microscopic physical mechanism of deep trap passivation based on density functional theory and characterized the contributions of orbital composition and orbital hybridization.

18.
Molecules ; 29(8)2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38675594

RESUMO

Cancer is a serious threat to human life and social development and the use of scientific methods for cancer prevention and control is necessary. In this study, HQSAR, CoMFA, CoMSIA and TopomerCoMFA methods are used to establish models of 65 imidazo[4,5-b]pyridine derivatives to explore the quantitative structure-activity relationship between their anticancer activities and molecular conformations. The results show that the cross-validation coefficients q2 of HQSAR, CoMFA, CoMSIA and TopomerCoMFA are 0.892, 0.866, 0.877 and 0.905, respectively. The non-cross-validation coefficients r2 are 0.948, 0.983, 0.995 and 0.971, respectively. The externally validated complex correlation coefficients r2pred of external validation are 0.814, 0.829, 0.758 and 0.855, respectively. The PLS analysis verifies that the QSAR models have the highest prediction ability and stability. Based on these statistics, virtual screening based on R group is performed using the ZINC database by the Topomer search technology. Finally, 10 new compounds with higher activity are designed with the screened new fragments. In order to explore the binding modes and targets between ligands and protein receptors, these newly designed compounds are conjugated with macromolecular protein (PDB ID: 1MQ4) by molecular docking technology. Furthermore, to study the nature of the newly designed compound in dynamic states and the stability of the protein-ligand complex, molecular dynamics simulation is carried out for N3, N4, N5 and N7 docked with 1MQ4 protease structure for 50 ns. A free energy landscape is computed to search for the most stable conformation. These results prove the efficient and stability of the newly designed compounds. Finally, ADMET is used to predict the pharmacology and toxicity of the 10 designed drug molecules.


Assuntos
Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Inibidores de Proteínas Quinases , Piridinas , Relação Quantitativa Estrutura-Atividade , Piridinas/química , Piridinas/farmacologia , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Humanos , Aurora Quinases/antagonistas & inibidores , Aurora Quinases/química , Aurora Quinases/metabolismo , Imidazóis/química , Imidazóis/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia
19.
Zhongguo Zhong Yao Za Zhi ; 49(7): 1834-1847, 2024 Apr.
Artigo em Zh | MEDLINE | ID: mdl-38812196

RESUMO

This study compared the therapeutic difference effects of the raw and scorched rhubarb for the treatment of ulcerative colitis(UC) and explored their difference in chemical components and mechanisms by using ultra-high performance liquid chromatography-quadrupole-electrostatic field orbitrap high-resolution mass spectrometry(UPLC-QE-Orbitrap-MS) and network pharmacology. The UC therapeutic effects of Shaoyao Decoction with the raw rhubarb or the scorched rhubarb were evaluated by dextran sulfate sodium(DSS)-induced mouse model. The results showed that Shaoyao Decoction with either the raw rhubarb or the scorched rhubarb could relieve the UC symptoms of mice to different extents, while the scorched rhubarb-based formula showed advantages in reducing hemorrhagic diarrhea and inflammation levels. UPLC-QE-Orbitrap-MS was used to identify a total of 78 small molecules in the water decoction of the raw and scorched rhubarb. Multivariate statistical methods were used to screen components increasing significantly after the scorching process. The seven compounds included five free anthraquinones, gallic acid, and 5-hydroxymethylfurfural(HMF). Meanwhile, the nine compounds decreasing scorching were mainly combined anthraquinones and catechins-related compounds. Network pharmacology and molecular docking suggested that free anthraquinones, gallic acid, and 5-HMF may act on core targets such as B-cell lymphoma-2(BCL2), epidermal growth factor receptor(EGFR), tumor necrosis factor(TNF), and caspase-3(CASP3) and influence the signaling pathways such as phosphoinositide-3-kinase/protein kinase B(PI3K/Akt), hypoxia inducible factor-1(HIF-1), TNF, and mitogen-activated protein kinase(MAPK), so as to regulate the inflammation response, oxidative stress, and cell apoptosis to relieve UC symptoms. This study compared the therapeutic effects and chemical components of the raw and scorched rhubarb, providing the clinical reference for using rhubarb to treat UC.


Assuntos
Colite Ulcerativa , Medicamentos de Ervas Chinesas , Espectrometria de Massas , Farmacologia em Rede , Rheum , Rheum/química , Animais , Colite Ulcerativa/tratamento farmacológico , Camundongos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Cromatografia Líquida de Alta Pressão/métodos , Masculino , Humanos
20.
Zhongguo Zhong Yao Za Zhi ; 49(9): 2273-2280, 2024 May.
Artigo em Zh | MEDLINE | ID: mdl-38812127

RESUMO

Small nucleic acid drugs mainly include small interfering RNA(siRNA), antisense oligonucleotide(ASO), microRNA(miRNA), messenger RNA(mRNA), nucleic acid aptamer(aptamer), and so on. Its translation or regulation can be inhibited by binding to the RNA of the target molecule. Due to its strong specificity, persistence, and curability, small nucleic acid drugs have received considerable attention in recent years. Recent studies have shown that some miRNAs from animal and plant sources can stably exist in the blood, tissue, and organs of animals and human beings and exert pharmacological action by regulating the expression of various target proteins. This paper summarized the discovery of small nucleic acids derived from traditional Chinese medicine(TCM) and natural drugs and their cross-border regulatory mechanisms and discussed the technical challenges and regulatory issues brought by this new drug, which can provide new ideas and methods for explaining the complex mechanism of TCM, developing new drugs of small nucleic acids from TCM and natural medicine, and conducting regulatory scientific research.


Assuntos
Descoberta de Drogas , Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Humanos , Animais , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , MicroRNAs/genética , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/química , Ácidos Nucleicos/química
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