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1.
Neural Regen Res ; 20(3): 740-750, 2025 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38886939

RESUMEN

Lipid droplets serve as primary storage organelles for neutral lipids in neurons, glial cells, and other cells in the nervous system. Lipid droplet formation begins with the synthesis of neutral lipids in the endoplasmic reticulum. Previously, lipid droplets were recognized for their role in maintaining lipid metabolism and energy homeostasis; however, recent research has shown that lipid droplets are highly adaptive organelles with diverse functions in the nervous system. In addition to their role in regulating cell metabolism, lipid droplets play a protective role in various cellular stress responses. Furthermore, lipid droplets exhibit specific functions in neurons and glial cells. Dysregulation of lipid droplet formation leads to cellular dysfunction, metabolic abnormalities, and nervous system diseases. This review aims to provide an overview of the role of lipid droplets in the nervous system, covering topics such as biogenesis, cellular specificity, and functions. Additionally, it will explore the association between lipid droplets and neurodegenerative disorders. Understanding the involvement of lipid droplets in cell metabolic homeostasis related to the nervous system is crucial to determine the underlying causes and in exploring potential therapeutic approaches for these diseases.

2.
Chem Biodivers ; : e202401218, 2024 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-39275987

RESUMEN

In this research, the essential oils (EOs) from different parts of Ocimum gratissimum var. suave were chemically characterized and evaluated for insecticidal activity, especially against two common storage pests of Chinese herbal medicines: Tribolium castaneum and Liposcelis bostrychophila. Ocimum gratissimum is a plant with several medicinal values in traditional Chinese medicine. In the study, EOs were successfully extracted from inflorescences (OGI) and stem-leaf (OGLS) parts of O. gratissimum by steam distillation and 16 compounds were identified by gas chromatography-mass spectrometry (GC-MS), of which eugenol was the major constituent in both extracts. In fumigation toxicity tests against both pests, the EOs showed limited toxicity against T. castaneum but showed better toxicity against L. bostrychophila. Contact toxicity tests showed that OGLS had better insecticidal potential than OGI, while the insecticidal effect of eugenol sometimes exceeded that of EOs. In addition, repellency experiments showed that O. gratissimum EOs repelled the pests to varying degrees, with the effect being influenced by concentration and exposure time. The results suggest that O. gratissimum EOs could be a promising alternative to synthetic insecticides for sustainable utilization.

3.
Front Oncol ; 14: 1416254, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39220650

RESUMEN

Background and aims: Hepatic perivascular epithelioid cell tumor (PEComa) is a rare type of mesenchymal neoplasm and lacks systematic reports. The aim was to analyze the features of hepatic PEComa in order to provide our own experience for diagnosis and management from a single center. Methods: We retrospectively analyzed clinical data, imaging findings, pathology, treatments and prognosis of 36 patients with hepatic PEComa in the First Affiliated Hospital of Zhengzhou University from January 2016 to September 2023. Results: 29 females and 7 males (median age, 47.8 years) were included in this study. The majority (26/36, 72.2%) of patients were diagnosed incidentally with non-specific symptoms. Abnormal enhancement of enlarged blood vessels (27/36,75%) can be observed on CT/MRI and only 7 patients (19.4%) were correctly diagnosed by imaging examinations. The positive immunohistochemical expressions were HMB-45(35/36,97.2%), Melan-A (34/35,97.1%), SMA (23/26,88.5%) and CD34(86.7%,26/30). Treatments include resection (24/36,67.7%), radiofrequency ablation (6/36,16.7%), transcatheter arterial chemoembolization(1/36,2.7%), conservative clinical follow-up(2/36,5.6%), and sirolimus-chemotherapy (3/36,8.3%). During the follow-up period (range, 2-81 months), except for one patient with a single intrahepatic recurrence and 3 malignant patients died in 6 months, the remaining patients had no signs of recurrence and metastasis. Conclusions: Hepatic PEComa has no specific clinical features and mainly depends on clinicopathological characteristics for accurate diagnosis. Resection is the best treatment for benign PEComa, but TACE and radiofrequency ablation can also be considered in case of contraindications for surgery.

4.
J Am Chem Soc ; 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39225242

RESUMEN

Single-bonded polymeric nitrogen has gained tremendous research interest because of its unique physical properties and great potential applications. Despite much progress in theoretical predictions, it is still challenging to experimentally synthesize polynitrogen compounds with novel all-single-bonded units. Herein, we have synthesized two brand-new lanthanum supernitrides LaN8, through a direct reaction between La and N2 in laser-heated diamond anvil cells at megabar pressures. Our experiments and calculations revealed that two LaN8 phases had the R-3 and P4/n symmetry characterized by a unique 2D network with N18 macro-rings and cagelike N8 building blocks, respectively. Differing from known polynitrogen structures, these two polymers were composed of single-bonded nitrogen atoms belonging to sp3 and sp2 hybridizations. In particular, P4/n LaN8 possessed the longest N-N bond length among all of the experimentally reported metal nitrides, potentially being a high-energy-density material. The present study opens a fresh, promising avenue for the rational design and discovery of new supernitrides with unique nitrogen structures via the high-pressure treatment.

5.
Pain Manag Nurs ; 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39242233

RESUMEN

PURPOSE: Explore factors influencing pain management among female breast cancer survivors aged 65+ years with moderate to severe pain based on a score of 4 or greater on the 0-10 numeric rating scale. DESIGN: Qualitative descriptive study. METHODS: We interviewed 21 purposefully sampled women aged 65+ years who experienced moderate to severe pain. Researchers coded interview transcripts for factors affecting study participants' pain management experiences. RESULTS: Pain management facilitators included patient-centered interactions with care teams and reliance on psychosocial assets. Challenges included ineffective care team interactions and participants' negative perceptions of opioid analgesia. Other factors included pain attributed to cancer treatment, pain management plan adherence, and psychosocial influencers. CONCLUSIONS: With regard to this sample, patient-centered communication and pain management education help female breast cancer survivors aged 65+ years manage their pain. Mitigation of opioid stigma and undermanaged painful comorbid conditions could further optimize pain management. Further research on the effects of breast cancer treatment, level of adherence to pain management recommendations, and psychosocial influences on pain management is needed. CLINICAL IMPLICATIONS: Providing contact information for care team members during and after clinic hours facilitates open communication, including timely reporting of new and undertreated pain. Collaborating with the patient and care team on a clear pain management plan and establishing parameters for when to notify the care team empower patients to optimize management of their pain. Verifying patients' understanding of prescribed analgesia and management of side effects and providing education as needed may reduce negative perceptions of opioid analgesia.

6.
Food Chem ; 463(Pt 1): 141122, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39243609

RESUMEN

Carbon quantum dots (CQDs) are ideal fluorescent probes for rapid detection. This paper reviews the synthesis methods of CQDs, their application in the rapid detection of antibiotics and heavy metals in the environment and food, and the underlying detection mechanisms. The hydrothermal method is the most commonly used for synthesis, and CQDs doped with heteroatoms (such as N, P and S) exhibit superior fluorescence performance. In the presence of antibiotics and heavy metals, the fluorescence of CQDs can be quenched or enhanced. Single-signal and dual-signal probes can be developed using the fluorescence, phosphorescence and absorbance of CQDs, enabling rapid detection of various antibiotics (e.g., tetracycline, quinolone and beta-lactam antibiotics) and heavy metals (e.g., Cd2+, Cr6+, Fe3+, Hg2+, and Pb2+). With the combination of smartphones and fluorescent probe test strips developed based on CQDs, on-the-spot rapid detection can be realized. This review offers new insights into the rapid detection of CQDs.

7.
Biol Reprod ; 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39303127

RESUMEN

Recurrent miscarriage (RM) is a chronic and heterogeneous pregnancy disorder lacking effective treatment. Alterations at the maternal-fetal interface are commonly observed in RM, with the loss of certain cell subpopulations believed to be a key cause. Through single-cell sequencing of RM patients and healthy donors, we aim to identify aberrancy of cellular features in RM tissues, providing new insights into the research. Natural killer (NK) cells, the most abundant immune cells in the decidua, are traditionally classified into dNK1, dNK2, and dNK3. In this study, we identified a new subset, dNK1/2, absent in RM tissues. This subset was named because it expresses biomarkers of both dNK1 and dNK2. With further analysis, we discovered that dNK1/2 cells play roles in immunoregulation and cytokine secretion. On the villous side of the interface, a notable decrease of extravillous trophoblast (EVT) cells was identified in RM tissues. We clustered EVTs into EVT1 (absent in RM) and EVT2 (retained in RM). Pseudotime analysis revealed distinct differentiation paths, identifying CCNB1, HMGB1, and NPM1 as EVT1 biomarkers. Additionally, we found that EVT1 is involved in the regulation of cell death, while EVT2 exhibited more angiogenic activity. Cell communication analysis revealed that interaction between EVT1 and dNK1/2 mediates chemotaxis and endothelial cell regulation, crucial for spiral artery remodeling. The loss of this interaction may impair decidualization, which is associated with RM. In summary, we propose that the loss of dNK1/2 and EVT1 cells is a significant pathological feature of RM.

8.
J Colloid Interface Sci ; 678(Pt B): 353-365, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39250838

RESUMEN

Nitrocyclohexane (NCH) hydrogenation to cyclohexanone oxime (CHO) is of great significance in the production of caprolactam. In this work, CuFeAl-Layered Double Hydroxide (CuFeAl-LDH) catalysts with lamellar structure were prepared by co-precipitation method and applied for NCH hydrogenation, and the promoting role of FeOx was discussed. It was found that FeOx species promote the reduction of Cu2+ and control the ratio of Cu+ to Cu0. In situ DRIFT and density-functional theory (DFT) calculation results confirm that the presence of FeOx species can act as lewis base site to reduce the acid sites and facilitate the isomerization of nitrosocyclohexane to CHO, and promotes the adsorption of NCH and the desorption of the formed CHO to prevent its further reaction to form byproducts. CuFe0.05Al shows the best catalytic performance of 100 % NCH conversion and 93.35 % selectivity to CHO under mild conditions. This work provides a new idea for the design of non-noble metal-based catalysts with high activity for the selective hydrogenation of nitro compounds.

9.
J Med Chem ; 67(17): 14820-14839, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39140772

RESUMEN

Various small molecule GLP1R agonists have been developed and tested for treating type 2 diabetes (T2DM) and obesity. However, many of these new compounds have drawbacks, such as potential hERG inhibition, lower activity compared to natural GLP-1, limited oral bioavailability in cynomolgus monkeys, and short duration of action. Recently, a new category of 3-phenyloxetane derivative GLP1R agonists with enhanced hERG inhibition has been discovered. Using an AIDD/CADD method, compound 14 (DD202-114) was identified as a potent and selective GLP1R agonist, which was chosen as a preclinical candidate (PCC). Compound 14 demonstrates full agonistic efficacy in promoting cAMP accumulation and possesses favorable drug-like characteristics compared to the clinical drug candidate Danuglipron. Additionally, in hGLP-1R knock-in mice, compound 14 displayed a sustained pharmacological effect, effectively reducing blood glucose levels and food intake. These findings suggest that compound 14 holds promise as a future treatment option for T2DM and obesity, offering improved properties.


Asunto(s)
Diseño de Fármacos , Receptor del Péptido 1 Similar al Glucagón , Receptor del Péptido 1 Similar al Glucagón/agonistas , Receptor del Péptido 1 Similar al Glucagón/metabolismo , Animales , Humanos , Ratones , Relación Estructura-Actividad , Masculino , Hipoglucemiantes/farmacología , Hipoglucemiantes/síntesis química , Hipoglucemiantes/química , Hipoglucemiantes/farmacocinética , Hipoglucemiantes/uso terapéutico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Glucemia/efectos de los fármacos , Glucemia/metabolismo , Receptores de Glucagón/agonistas , Receptores de Glucagón/metabolismo
10.
Anal Methods ; 16(34): 5812-5819, 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39140766

RESUMEN

The early detection of bacterial species plays a crucial role in patient prognosis and the development of effective therapeutic regimens. This study introduces an accessible and promising colorimetric sensor array designed to classify gram-positive (G+) and gram-negative (G-) bacterial species. The classification relies on 6 chemical ligands with dimethylamino/amino groups as sensing elements and silver nanotriangles as colorimetric probes. Using these specific sensor arrays, we successfully differentiated G- and G+ bacterial species and discriminated individual bacterial strains, and the sensors exhibited remarkable reproducibility and high sensitivity. Moreover, the sensor array can identify bacterial mixtures and bacteria at varying concentrations, underscoring its versatility. In summary, this sensor array offers an effective tool for bacterial analysis with promising applications in the field of biomedical diagnostics.


Asunto(s)
Colorimetría , Ligandos , Colorimetría/métodos , Plata/química , Bacterias Gramnegativas/aislamiento & purificación , Bacterias Gramnegativas/clasificación , Bacterias Grampositivas/aislamiento & purificación , Nanopartículas del Metal/química , Reproducibilidad de los Resultados
11.
J Org Chem ; 89(17): 12559-12575, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39189641

RESUMEN

The catalytic atroposelective synthesis of N-N axially chiral indolylamides was established via dynamic kinetic resolution, which makes use of chiral Lewis base-catalyzed asymmetric acylation of N-acylaminoindoles as a new type of platform molecule with anhydrides. By this strategy, a series of N-N axially chiral indolylamides were synthesized in overall good yields (up to 98%) with excellent enantioselectivities (up to 99% ee). Moreover, some of these N-N axially chiral indolylamides display some extent of anticancer activity, which demonstrates their potential application in medicinal chemistry. Therefore, this work has not only provided a new strategy for the synthesis of N-N axially chiral monoaryl indoles but also offered a new member of N-N axially chiral monoaryl indoles with configurational stability and promising application, thereby solving the challenges in atroposelective synthesis and application of N-N axially chiral monoaryl indoles.

13.
J Med Biochem ; 43(4): 587-596, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-39139162

RESUMEN

Background: To explore the correlation between left atrial appendage morphology, blood flow velocity and plasma galectin-3 and thrombosis in patients with atrial fibrillation. Methods: Patients with atrial fibrillation who received treatment and completed ultrasound examination in hospital from 2022 to December 2023 were enrolled. According to whether there was left atrial appendage thrombosis, the patients were divided into a control group (no left atrial appendage thrombosis was found) and a study group (left atrial appendage thrombosis was found). The morphology and structure of the left atrial appendage, blood flow velocity and plasma galectin-3 level were recorded exploring its correlation with left atrium thrombosis. Results: A total of 330 patients with atrial fibrillation were enrolled, including 278 in the control group and 52 in the study group. Left group and the control group of morphological structure differences (P < 0.05). The main lobe length, ostial area, longest diameter, shortest diameter, left atrial appendage volume and left atrial volume in the study group were higher than those in the control group (P < 0.05). The left atrial appendage emptying velocity, filling velocity and left ventricular ejection fraction of the study group were lower than those of the control group, and the left ventricular end-diastolic diameter was higher than that of the control group (P < 0.05). Group of white blood cell count, neutrophils/lymphocyte ratio, plasma galactose lectin-3 levels were higher than control group (P < 0.05). ROC curve analysis of left atrial appendage emptying velocity, left atrial appendage filling velocity, left atrial enddiastolic diameter and left atrial ejection fraction had higher diagnostic value (P < 0.05). Conclusions: Left atrial appendage morphology, blood flow velocity and plasma galectin-3 level are important factors to evaluate the risk of left atrial appendage thrombosis in patients with atrial fibrillation. This study improves the understanding of thrombosis, further elucidates the risk factors for thrombosis, and improves patient prognosis.

14.
Orthop Surg ; 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39139066

RESUMEN

OBJECTIVES: Cervical spondylosis may lead to changes in the sagittal parameters of the neck and trigger compensatory alterations in systemic sagittal parameters. However, there is currently a dearth of comparative research on the changes and compensatory alterations to sagittal parameters resulting from different types of cervical spondylosis. This study compared the preoperative sagittal alignment sequences among patients with cervical spondylotic radiculopathy (CSR), ossification of the posterior longitudinal ligament (OPLL), and cervical spondylotic myelopathy (CSM) caused by factors resulting from non-OPLL factors. MATERIALS AND METHODS: Full length lateral X-ray of the spine and cervical computed tomography (CT) of 256 patients (134 men, 122 women; mean age, 56.9 ± 9.5 years) were analyzed retrospectively. A total of 4096 radiomics features were measured through the lateral X-ray by two spinal surgeons with extensive experience. The clinical symptoms measures were the Japanese Orthopaedic Association (JOA) score, number of hand actions in 10 s, hand-grip strength, visual analog scale (VAS) score. Normally distributed data was compared using one-way analysis of variance (ANOVA) for parametric variables and χ2 test were used to analyze the categorical data. RESULTS: In the OPLL group, the C2-C7 Cobb angle was greater than in the CSR and CSM groups (19.8 ± 10.4°, 13.3 ± 10.3°, and 13.9 ± 9.9°, respectively, p < 0.001). Additionally, the C7-S1 SVA measure was found to be situated in the anterior portion with regards to the CSM and CSR groups (19.7 ± 58.4°, -6.3 ± 34.3° and -26.3 ± 32.9°, p < 0.001). Moreover, the number of individuals with C7-S1 SVA >50 mm was significantly larger than the CSM group (26/69, 11/83, p < 0.001). In the CSR group, the TPA demonstrated smaller values compared to the OPLL group (8.8 ± 8.5°, 12.7 ± 10.2°, p < 0.001). Furthermore, the SSA was comparatively smaller as opposed to both the OPLL and CSM groups (49.6 ± 11.2°, 54.2 ± 10.8° and 54.3 ± 9.3°, p < 0.05). CONCLUSION: Patients with OPLL exhibit greater cervical lordosis than those with CSR and CSM. However, OPLL is more likely to result in spinal imbalance when compared to the CSM group. Furthermore, OPLL and CSM patients exhibit anterior trunk inclination and worse global spine sagittal parameters in comparison to CSR patients.

15.
Front Immunol ; 15: 1400722, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39170612

RESUMEN

Background: Although neoadjuvant therapy has brought numerous benefits to patients, not all patients can benefit from it. Chemokines play a crucial role in the tumor microenvironment and are closely associated with the prognosis and treatment of colorectal cancer. Therefore, constructing a prognostic model based on chemokines will help risk stratification and providing a reference for the personalized treatment. Methods: Employing LASSO-Cox predictive modeling, a chemokine-based prognostic model was formulated, harnessing the data from TCGA and GEO databases. Then, our exploration focused on the correlation between the chemokine signature and elements such as the immune landscape, somatic mutations, copy number variations, and drug sensitivity. CXCL10+M1 macrophages identified via scRNA-seq. Monocle2 showed cell pseudotime trajectories, CellChat characterized intercellular communication. CytoTRACE analyzed neoadjuvant therapy stemness, SCENIC detected cell type-specific regulation. Lastly, validation was performed through multiplex immunofluorescence experiments. Results: A model based on 15 chemokines was constructed and validated. High-risk scores correlated with poorer prognosis and advanced TNM and clinical stages. Individuals presenting elevated risk scores demonstrated an increased propensity towards the development of chemotherapy resistance. Subsequent scRNA-seq data analysis indicated that patients with higher presence of CXCL10+ M1 macrophages in tumor tissues are more likely to benefit from neoadjuvant therapy. Conclusion: We developed a chemokine-based prognostic model by integrating both single-cell and bulk RNA-seq data. Furthermore, we revealed epithelial cell heterogeneity in neoadjuvant outcomes and identified CXCL10+ M1 macrophages as potential therapy response predictors. These findings could significantly contribute to risk stratification and serve as a key guide for the advancement of personalized therapeutic approaches.


Asunto(s)
Quimiocina CXCL10 , Neoplasias Colorrectales , Terapia Neoadyuvante , Microambiente Tumoral , Humanos , Neoplasias Colorrectales/terapia , Neoplasias Colorrectales/inmunología , Neoplasias Colorrectales/mortalidad , Quimiocina CXCL10/genética , Quimiocina CXCL10/metabolismo , Terapia Neoadyuvante/métodos , Pronóstico , Microambiente Tumoral/inmunología , Biomarcadores de Tumor , Macrófagos/inmunología , Macrófagos/metabolismo , Macrófagos Asociados a Tumores/inmunología , Macrófagos Asociados a Tumores/metabolismo , Femenino , Masculino , Resultado del Tratamiento , Quimiocinas/metabolismo , Quimiocinas/genética
16.
Intensive Crit Care Nurs ; 84: 103744, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39089198

RESUMEN

OBJECTIVES: To assess the efficacy of early rehabilitation program for VV-ECMO patients and observe the influence on the respiratory and skeletal muscles. DESIGN: A cohort study. SETTING: The study was conducted with VVECMO patients in a comprehensive ICU with 32 beds. MAIN OUTCOME MEASURES: Ultrasound measurements were performed on each patients on day 1, 4, 7, 10, and 14, including diaphragmatic excursion (DE), diaphragmatic thickening fraction (DTF), intercostal muscle thickening fraction (ICMTF), thickness of the rectus femoris (RF), thickness of vastus intermedius (VI), and rectus femoris cross-sectional area (RF-CSA). Data on basic characteristics, results of ultrasound measurements, patients outcomes and adverse events were collected. RESULTS: 22 patients received usual rehabilitation measures were set as the control group and 23 patients underwent early rehabilitation program were set as the study group. There were no differences in diaphragmatic excursion, diaphragmatic thickening fraction, intercostal muscle thickening fraction, thickness of rectus femoris, thickness of vastus intermedius, rectus femoris cross-sectional area between two groups on day 1 after VV-ECMO treatment (P > 0.05). The variation of diaphragmatic thickening fraction and intercostal muscle thickening fraction decreased on the day 7 and 14 after treatment (P < 0.05). The variation of vastus intermedius thickness and rectus femoris cross-sectional area in the study group was less compared with those in the control group on day 4, 7, 10 and 14. The ECMO duration in the study group was shorter than that in the control group (12.00 [10.00-16.25] days vs. 8.00 [6.00-12.25] days, P = 0.002), but there was no difference in the duration of mechanical ventilation. CONCLUSION: Early rehabilitation program can ameliorate muscle atrophy. We recommend implementation of our rehabilitation program in VV-ECMO patients. This program can improve skeletal muscle atrophy and dysfunction in patients with VV-ECMO effectively and perhaps improve quality of life for patients in the future. IMPLICATIONS FOR CLINICAL PRACTICE: Early rehabilitation program put higher demands bedside nurses. It requires them to observe conditions of VVECMO patients closely, assess the feasibility of rehabilitation promptly, and monitor for any adverse reactions. Ultrasound measurement is a noninvasive and useful tool to assess muscle atrophy in ICU patients. Early rehabilitation program can improve skeletal muscle atrophy and dysfunction in patients with VV-ECMO effectively.


Asunto(s)
Oxigenación por Membrana Extracorpórea , Humanos , Masculino , Femenino , Persona de Mediana Edad , Estudios de Cohortes , Oxigenación por Membrana Extracorpórea/métodos , Oxigenación por Membrana Extracorpórea/estadística & datos numéricos , Adulto , Unidades de Cuidados Intensivos/organización & administración , Unidades de Cuidados Intensivos/estadística & datos numéricos , Ultrasonografía/métodos
17.
Chem Biodivers ; : e202400818, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39110524

RESUMEN

Insect infestations continually endanger stored goods, underscoring the significance of discovering eco-friendly insecticides for pest management. Essential oils (EOs) from different parts of Toddalia asiatica (leaf, fruit and branch) were extracted by hydrodistillation and analyzed by GC-MS. Carvene, p-cymene and muurolene are the principal compounds of T. asiatica leaf (TAL), T. asiatica fruit (TAF) and T. asiatica branch (TAB) EO respectively. Our work aimed to assess the contact toxicity and repellent effects of EOs on two storage pests, Tribolium castaneum and Lasioderma serricorne. All tested EOs exhibited obvious contact toxicity, especially, TAL EO against T. castaneum (33.48 µg/adult) and TAF EO against L. serricorne (16.42 µg/adult). Repellency tests revealed that TAL and TAF EOs, at a concentration of 78.63 nL/cm2, achieved nearing 100% efficiency against T. castaneum. These results suggest that EOs of T. asiatica could be used as effective botanical insecticides for managing stored-product insects.

18.
Plants (Basel) ; 13(15)2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39124162

RESUMEN

The mechanism by which nitrate inhibits nitrogen fixation in soybean (Glycine max L.) is not fully understood. Accumulation of ureide in soybean plant tissues may regulate the nitrogen fixation capacity through a feedback pathway. In this study, unilaterally nodulated dual-root soybeans prepared by grafting were grown in sand culture. They were subjected to the removal of the nodulated side roots, and were given either nitrate supply or no supply to the non-nodulated side roots for 3 days (experiment I). Additionally, they received nitrate supply to the non-nodulated side roots for 1-14 days (experiment II). The results showed that nitrate supply increased the levels of asparagine and ureide in soybean shoots (Experiment I). In Experiment II, nodule dry weight, nodule number, nodule nitrogenase activity, and nodule urate oxidase activity decreased significantly after 3, 7, and 14 days of nitrate supply. Ureide content in the shoots and nodules increased after 1, 3, and 7 days of nitrate supply, but decreased after 14 days of nitrate supply. There was a significant positive correlation between urate oxidase activity and nitrogenase activity. Hence, we deduced that nitrate supply increased the asparagine content in soybean shoots, likely inhibiting ureide degradation, which induced the accumulation of ureide in soybean shoots and nodules, and, in turn, feedback inhibited the nodule nitrogen fixation. In addition, urate oxidase activity can be used to assess the nitrogen fixation capacity of nodules.

19.
Materials (Basel) ; 17(16)2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39203140

RESUMEN

Powder metallurgy (PM) technology is extensively employed in the manufacturing sector, yet its processing presents numerous challenges. To alleviate these difficulties, green machining of PM green compacts has emerged as an effective approach. The aim of this research is to explore the deformation features of green compacts and assess the impact of various machining parameters on the force of cutting. The cutting variables for compacts of PM green were modeled, and the cutting process was analyzed using Abaqus (2022) software. Subsequently, the orthogonal test ANOVA method was utilized to evaluate the significance of each parameter for the cutting force. Optimization of the machining parameters was then achieved through a genetic algorithm for neural network optimization. The investigation revealed that PM green compacts, which are brittle, undergo a plastic deformation stage during cutting and deviate from the traditional model for brittle materials. The findings indicate that cutting thickness exerts the most substantial influence on the cutting force, whereas the speed of cutting, the tool rake angle, and the radius of the rounded edge exert minimal influence. The optimal parameter combination for the cutting of PM green compacts was determined via a genetic algorithm for neural network optimization, yielding a cutting force of 174.998 N at a cutting thickness of 0.15 mm, a cutting speed of 20 m/min, a tool rake angle of 10°, and a radius of the rounded edge of 25 µm, with a discrepancy of 4.05% from the actual measurement.

20.
Angew Chem Int Ed Engl ; : e202411180, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39192703

RESUMEN

This work reports synthesis of a germylene based donor-acceptor molecule and its thermal excitation to a triplet state by coordination with a Lewis acid. Products have been characterized by single crystal X-ray diffraction, EPR spectroscopy, and SQUID measurement, in conjunction with DFT calculation. The singlet-triplet energy gap of the donor-acceptor molecule is dramatically reduced from -18.8 to -7.2 kcal/mol by the coordination with B(C6F5)3 (BCF), which enables an intramolecular single electron transfer from one germylene moiety to another upon heating, forming an intramolecular radical ion pair with diradical character. The work provides an approach to the formation of thermally populated open-shell species of heavier main group elements.

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