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1.
ACS Photonics ; 11(8): 3288-3295, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39184184

RESUMEN

A main, yet-unsolved challenge in splicing hollow-core fiber (HCF) into standard single-mode fiber (SMF) systems lies in managing the strong Fresnel back-reflection that occurs when the light travels from the empty core of the HCF into the glass core of the SMF or vice versa. This impacts the performance of fiber systems that combine SMFs and HCFs due to effects such as multipath interference. Here, we demonstrate a new technique that combines angle-cleaving the HCF, which reduces the back-reflection, with offset-splicing the mode-field adapter to the SMF, which compensates for the refraction at the glass-air interface, enabling us to achieve low coupling loss. We first analyze this novel configuration via simulations and show that it is possible to achieve a coupling loss that is comparable to a conventional flat-cleaved splice. Subsequently, we fabricate an SMF-HCF connection with a loss of 0.6 dB prior to arcing (1.2 dB after splicing) and ultralow back-reflection (-64 dB) by applying an optimized 4.5° angle and 5 µm offset. To the best of our knowledge, this is the first low-insertion-loss spliced SMF-HCF connection where a widely acceptable level of back-reflection of <-60 dB is achieved.

3.
Front Oncol ; 14: 1400109, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39193382

RESUMEN

Background: Lymph node metastasis (LNM) is an important prognostic factor for cervical cancer (CC) and determines the treatment strategy. Hematological indicators have been reported as being useful biomarkers for the prognosis of a variety of cancers. This study aimed to evaluate the feasibility of machine learning models characterized by preoperative hematological indicators to predict the LNM status of CC patients before surgery. Methods: The clinical data of 236 patients with pathologically confirmed CC were retrospectively analyzed at the Gynecology Oncology Department of the First Affiliated Hospital of Bengbu Medical University from November 2020 to August 2022. The least absolute shrinkage and selection operator (LASSO) was used to select 21 features from 35 hematological indicators and for the construction of 6 machine learning predictive models, including Adaptive Boosting (AdaBoost), Gaussian Naive Bayes (GNB), and Logistic Regression (LR), as well as Random Forest (RF), Support Vector Machines (SVM), and Extreme Gradient Boosting (XGBoost). Evaluation metrics of predictive models included the area under the receiver operating characteristic curve (AUC), accuracy, specificity, sensitivity, and F1-score. Results: RF has the best overall predictive performance for ten-fold cross-validation in the training set. The specific performance indicators of RF were AUC (0.910, 95% confidence interval [CI]: 0.820-1.000), accuracy (0.831, 95% CI: 0.702-0.960), specificity (0.835, 95% CI: 0.708-0.962), sensitivity (0.831, 95% CI: 0.702-0.960), and F1-score (0.829, 95% CI: 0.696-0.962). RF had the highest AUC in the testing set (AUC = 0.854). Conclusion: RF based on preoperative hematological indicators that are easily available in clinical practice showed superior performance in the preoperative prediction of CC LNM. However, investigations on larger external cohorts of patients are required for further validation of our findings.

4.
Life Sci ; 352: 122893, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38971367

RESUMEN

AIMS: Neonatal necrotizing enterocolitis (NEC) is a leading cause of intestine inflammatory disease, and macrophage is significantly activated during NEC development. Posttranslational modifications (PTMs) of proteins, particularly ubiquitination, play critical roles in immune response. This study aimed to investigate the effects of ubiquitin-modified proteins on macrophage activation and NEC, and discover novel NEC-related inflammatory proteins. MATERIALS AND METHODS: Proteomic and ubiquitin proteomic analyses of intestinal macrophages in NEC/healthy mouse pups were carried out. In vitro macrophage inflammation model and in vivo NEC mouse model, as well as clinical human samples were used for further verification the inhibitor of nuclear factor-κB kinase α (IKKα) ubiquitination on NEC development through Western blot, immunofluorescence, quantitative real-time polymerase chain reaction (qRT-PCR) and flow cytometry. KEY FINDINGS: We report here that IKKα was a new ubiquitin-modified protein during NEC through ubiquitin proteomics, and RING finger protein 31 (RNF31) acted as an E3 ligase to be involved in IKKα degradation. Inhibition of IKKα ubiquitination and degradation with siRNF31 or proteasome inhibitor decreased nuclear factor-κB (NF-κB) activation, thereby decreasing the expression of pro-inflammatory factors and M1 macrophage polarization, resulting in reliving the severity of NEC. SIGNIFICANCE: Our study suggests the activation of RNF31-IKKα-NF-κB axis triggering NEC development and suppressing RNF31-mediated IKKα degradation may be therapeutic strategies to be developed for NEC treatment.


Asunto(s)
Enterocolitis Necrotizante , Quinasa I-kappa B , Inflamación , FN-kappa B , Ubiquitina-Proteína Ligasas , Ubiquitinación , Animales , Femenino , Humanos , Recién Nacido , Masculino , Ratones , Animales Recién Nacidos , Modelos Animales de Enfermedad , Enterocolitis Necrotizante/metabolismo , Enterocolitis Necrotizante/patología , Quinasa I-kappa B/metabolismo , Inflamación/metabolismo , Inflamación/patología , Intestinos/patología , Macrófagos/metabolismo , Ratones Endogámicos C57BL , FN-kappa B/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética
5.
Animals (Basel) ; 14(14)2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39061576

RESUMEN

To date, more than 20 species in the genus Cyclospora have been reported. Among them, Cyclospora cayetanensis has been recognized as the causative agent of human cyclosporiasis, which is characterized by severe intestinal injury and prolonged diarrhea in patients with immune dysfunction. The presence of C. cayetanensis in cattle has been confirmed. To date, however, no surveillance data are available on the occurrence and prevalence of Cyclospora spp. in cattle in Shanxi Province, North China. In the present study, a total of 761 fecal samples collected from cattle in three representative counties (Qi, Jishan, and Shanyin) in this Province were examined for Cyclospora spp. by using a polymerase-chain-reaction-restriction-fragment-length polymorphism (PCR-RFLP) test based on the nuclear small subunit ribosomal RNA (SSU rRNA) gene. The prevalence of Cyclospora spp. in cattle was 2.1%, and region, age, sex, and breed were not identified to be risk factors. Molecular evolutionary analysis based on the SSU rRNA sequences revealed that all 12 of the isolates were relatively distant from the human pathogen C. cayetanensis; seven isolates were grouped with Cyclospora colobi, whereas the others were grouped with cattle Cyclospora spp. reported previously. Though C. cayetanensis was not detected in cattle in the present study, more investigations should be performed in human populations, other animal species, or cattle from other regions of Shanxi Province and other environmental sources from the One Health perspective.

6.
J Phys Chem A ; 128(28): 5473-5480, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-38968435

RESUMEN

Liquid-phase synthesis of atomically precise nanoclusters has experienced rapid development recently, where polar solvents are indispensable in such a process. However, the regulation effect of solvents on the structural and electronic properties of different metal clusters and cluster assembly materials is still not well understood. Herein, a comprehensive density functional theory calculation has been performed to explore the solvation effect on heteroatom-doped endohedral gold clusters that always have remarkable stabilities and tunable electronic structures. The solvation free energy of the M@Au12 clusters (M = Cr, Mo, W, Co, Rh, Ir, Cu, Ag, and Au) was found to be related to the charge distribution of the central doped-atom M and the outer Au12 cage. Moreover, the aqueous solvent was observed to be able to increase the adsorption capacity of M@Au12 to O2 following the activation of O2 through the charge transfer from M@Au12 to O2, in which the transferred electrons occupy the π antibonding orbital of O2. In addition, the water solvent can also improve the hydrogenation reaction of O2 to form OOH over M@Au12, where the activation energy barrier for this process is very low with the participation of the solvent. Considering the importance of solvents in the liquid-phase synthesis of atomically precise clusters, these findings highlighted here could provide valuable theoretical guidance in potential applications of functional gold nanoclusters, especially in the liquid-phase cluster catalysis.

7.
J Colloid Interface Sci ; 675: 815-824, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-39002232

RESUMEN

Oxygen vacancy engineering in transition metal oxides is an effective strategy for improving catalytic performance. Herein, defect-enriched Mn2O3 catalysts were constructed by controlling the calcination temperature. The high content of oxygen vacancies and accompanying Mn4+ ions were generated in Mn2O3 catalysts calcined at low temperature, which could greatly improve the low-temperature reducibility and migration of surface oxygen species. DFT theoretical calculations further confirmed that molecular oxygen and toluene were easily adsorbed over defective α-Mn2O3 (222) facets with an energy of -0.29 and -0.48 eV, respectively, and corresponding OO bond length is stretched to 1.43 Å, resulting in the highly reactive oxygen species. Mn2O3-300 catalyst with abundant oxygen vacancies exhibited the highest specific reaction rate and lowest activation energy. Furthermore, the optimized catalyst possessed the outstanding stability, water tolerance and CO2 yield. In comparison with the fresh Mn2O3-300 catalyst, the physical structure and surface property of the used catalyst remained almost unchanged regardless of whether undergoing the stability test at consecutive catalytic runs as well as high temperature, and water resistance test. In situ DRIFTS spectra further elucidated that introducing the water vapor had little effect on the reaction intermediates, indicating the excellent durability of the defect-enriched catalyst.

8.
J Cardiothorac Surg ; 19(1): 423, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38970107

RESUMEN

OBJECTIVE: To compare the treatment outcomes among percutaneous mechanical thrombectomy (PMT) with AngioJet, Catheter-directed thrombolysis (CDT), and a combination of both. METHODS: One hundred forty nine patients with acute or sub-acute iliac-femoral vein thrombosis accepting CDT and/or PMT were divided into three groups respectively: PMT group, CDT group, PMT + CDT group (PMT followed by CDT). The severity of thrombosis was evaluated by venographic scoring system. Technical success was defined as restored patent deep venous blood flow after CDT and/or PMT. Clinical follow-up were assessed by ultrasound or venography imaging. The primary endpoints were recurrence of DVT, and severity level of post-thrombotic syndrome (PTS) during the follow-up. RESULTS: Technical success and immediate clinical improvements were achieved on all patients. The proportion of sub-acute DVT and the venographic scoring in PMT + CDT group were significantly higher than that in CDT group and PMT group (proportion of sub-acute DVT: p = 0.032 and p = 0.005, respectively; venographic scoring: p < 0.001, respectively). The proportion of May-Thurner Syndrome was lower in PMT group than that in CDT and PMT + CDT group (p = 0.026 and p = 0.005, respectively). The proportion of DVT recurrence/stent thrombosis was significantly higher in CDT group than that in PMT + CDT group (p = 0.04). The severity of PTS was the highest in CDT group ( χ2 = 14.459, p = 0.006) compared to PMT group (p = 0.029) and PMT + CDT group (p = 0.006). CONCLUSION: Patients with sub-acute DVT, high SVS scoring and combined May-Thurner Syndrome were recommended to take PMT + CDT treatment and might have lower rate of DVT recurrence/stent thrombosis and severe PTS. Our study provided evidence detailing of PMT + CDT therapy.


Asunto(s)
Trombectomía , Terapia Trombolítica , Trombosis de la Vena , Humanos , Masculino , Trombosis de la Vena/terapia , Femenino , Persona de Mediana Edad , Terapia Trombolítica/métodos , Trombectomía/métodos , Resultado del Tratamiento , Adulto , Estudios Retrospectivos , Anciano , Vena Ilíaca/cirugía , Vena Ilíaca/diagnóstico por imagen , Terapia Combinada , Vena Femoral , Síndrome Postrombótico , Trombolisis Mecánica/métodos , Flebografía
9.
J Phys Chem Lett ; 15(27): 7028-7035, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38949686

RESUMEN

Traditional electron counting rules, like the Jellium model, have long been successfully utilized in designing superhalogens by modifying clusters to have one electron less than a filled electronic shell. However, this shell-filling approach, which involves altering the intrinsic properties of the clusters, can be complex and challenging to control, especially in experiments. In this letter, we theoretically establish that the oriented external electric field (OEEF) can substantially enhance the electron affinity (EA) of diverse aluminum-based metal clusters with varying valence electron configurations, leading to the creation of superhalogen species without altering their shell arrangements. This OEEF approach offers a noninvasive alternative to traditional superatom design strategies, as it does not disrupt the clusters' geometrical structures and superatomic states. These findings contribute a vital piece to the puzzle of constructing superalkalis and superhalogens, extending beyond conventional shell-filling strategies and potentially expanding the range of applications for functional clusters.

10.
Virology ; 598: 110188, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39059190

RESUMEN

Feline bocavirus (FBoV) is a globally distributed linear, single-stranded DNA virus infect cats, currently classified into three distinct genotypes. Although FBoV can lead to systemic infections, its complete pathogenic potential remains unclear. In this study, 289 blood samples were collected from healthy cats in Harbin, revealing an overall FBoV prevalence of 12.1%. Notably, genotypes 1 and 3 of FBoV were found co-circulating among the cat population in Harbin. Additionally, recombination events were detected, particularly in the newly discovered NG/104 and DL/102 strains. Furthermore, negative selection sites were predominantly observed across the protein coding genes of FBoV. These findings suggest a co-circulation of genetically diverse FBoV strains among cats in Harbin, indicate that purifying selection is the primary driving force shaping the genomic evolution of FBoV, and also underscore the importance of comprehensive surveillance efforts to enhance our understanding of the epidemiology and evolutionary characteristics of FBoV.


Asunto(s)
Bocavirus , Enfermedades de los Gatos , Variación Genética , Genotipo , Infecciones por Parvoviridae , Filogenia , Gatos , Animales , China/epidemiología , Enfermedades de los Gatos/virología , Enfermedades de los Gatos/epidemiología , Infecciones por Parvoviridae/veterinaria , Infecciones por Parvoviridae/virología , Infecciones por Parvoviridae/epidemiología , Bocavirus/genética , Bocavirus/clasificación , Bocavirus/aislamiento & purificación , Prevalencia , Recombinación Genética , Genoma Viral , Evolución Molecular
11.
Nano Lett ; 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38860507

RESUMEN

The majority of dislocations in nitride epilayers are edge threading dislocations (TDs), which diminish the performance of nitride devices. However, it is extremely difficult to reduce the edge TDs due to the lack of available slip systems. Here, we systematically investigate the formation mechanism of edge TDs and find that besides originating at the coalescence boundaries, these dislocations are also closely related to geometrical misfit dislocations at the interface. Based on this understanding, we propose a novel strategy to reduce the edge TD density of the GaN epilayer by nearly 1 order of magnitude via graphene-assisted remote heteroepitaxy. The first-principles calculations confirm that the insertion of graphene dramatically reduces the energy barrier required for interfacial sliding, which promotes a new strain release channel. This work provides a unique approach to directly suppress the formation of edge TDs at the source, thereby facilitating the enhanced performance of photoelectronic and electronic devices.

12.
J Endocrinol ; 262(2)2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38829257

RESUMEN

Cells actively engaged in de novo steroidogenesis rely on an expansive intracellular network to efficiently transport cholesterol. The final link in the transport chain is STARD1, which transfers cholesterol to the enzyme complex that initiates steroidogenesis. However, the regulation of ovarian STARD1 is not fully characterized, and even less is known about the upstream cytosolic cholesterol transporters STARD4 and STARD6. Here, we identified both STARD4 and STARD6 mRNAs in the human ovary but only detected STARD4 protein since the primary STARD6 transcript turned out to be a splice variant. Corpora lutea contained the highest levels of STARD4 and STARD1 mRNA and STARD1 protein, while STARD4 protein was uniformly distributed across ovarian tissues. Cyclic AMP analog (8Br-cAMP) and phorbol ester (PMA) individually increased STARD1 and STARD4 mRNA along with STARD1 protein and its phosphoform in cultured primary human luteinized granulosa cells (hGCs). STARD6 transcripts and STARD4 protein were unresponsive to these stimuli. Combining lower doses of PMA and 8Br-cAMP blunted the 8Br-cAMP stimulation of STARD1 protein. Increasing cholesterol levels by blocking its conversion to steroid with aminoglutethimide or by adding LDL reduced the STARD4 mRNA response to stimuli. Sterol depletion reduced the STARD1 mRNA and protein response to PMA. These data support a possible role for STARD4, but not STARD6, in supplying cholesterol for steroidogenesis in the ovary. We demonstrate for the first time how cAMP, PMA and sterol pathways separately and in combination differentially regulate STARD4, STARD6 and STARD1 mRNA levels, as well as STARD1 and STARD4 protein in human primary ovarian cells.


Asunto(s)
Ovario , Adulto , Femenino , Humanos , 8-Bromo Monofosfato de Adenosina Cíclica/farmacología , Células Cultivadas , Colesterol/metabolismo , AMP Cíclico/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Células de la Granulosa/metabolismo , Células de la Granulosa/efectos de los fármacos , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Proteínas de Transporte de Membrana , Ovario/metabolismo , Fosfoproteínas/metabolismo , Fosfoproteínas/genética , ARN Mensajero/metabolismo
13.
Front Neurol ; 15: 1407152, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38938777

RESUMEN

Background and objectives: Upwards of 50% of acute ischemic stroke (AIS) survivors endure varying degrees of disability, with a recurrence rate of 17.7%. Thus, the prediction of outcomes in AIS may be useful for treatment decisions. This study aimed to determine the applicability of a machine learning approach for forecasting early outcomes in AIS patients. Methods: A total of 659 patients with new-onset AIS admitted to the Department of Neurology of both the First and Second Affiliated Hospitals of Bengbu Medical University from January 2020 to October 2022 included in the study. The patient' demographic information, medical history, Trial of Org 10,172 in Acute Stroke Treatment (TOAST), National Institute of Health Stroke Scale (NIHSS) and laboratory indicators at 24 h of admission data were collected. The Modified Rankine Scale (mRS) was used to assess the 3-mouth outcome of participants' prognosis. We constructed nine machine learning models based on 18 parameters and compared their accuracies for outcome variables. Results: Feature selection through the Least Absolute Shrinkage and Selection Operator cross-validation (Lasso CV) method identified the most critical predictors for early prognosis in AIS patients as white blood cell (WBC), homocysteine (HCY), D-Dimer, baseline NIHSS, fibrinogen degradation product (FDP), and glucose (GLU). Among the nine machine learning models evaluated, the Random Forest model exhibited superior performance in the test set, achieving an Area Under the Curve (AUC) of 0.852, an accuracy rate of 0.818, a sensitivity of 0.654, a specificity of 0.945, and a recall rate of 0.900. Conclusion: These findings indicate that RF models utilizing general clinical and laboratory data from the initial 24 h of admission can effectively predict the early prognosis of AIS patients.

14.
Zhongguo Gu Shang ; 37(6): 6095-15, 2024 Jun 25.
Artículo en Chino | MEDLINE | ID: mdl-38910385

RESUMEN

OBJECTIVE: To explore clinical effect of vancomycin calcium sulfate combined with internal fixation on calcaneal beak-like fracture secondary to calcaneal osteomyelitis caused by diabetic foot. METHODS: From April 2018 to October 2021, a retrospective analysis was performed on 5 patients with calcaneal bone osteomyelitis secondary to diabetic foot, including 2 males and 3 females, aged from 48 to 60 years old;diabetes course ranged from 5 to 13 years;the courses of diabetic foot disease ranged from 18 to 52 days;5 patients were grade Ⅲ according to Wagner classification. All patients were treated with debridement, vancomycin bone cement implantation, negative pressure aspiration at stageⅠ, vancomycin calcium sulfate and internal fixation at stageⅡfor calcaneal beak-like fracture. Surgical incision and fracture healing time were recorded, and the recurrence of osteomyelitis was observed. American Orthopedic Foot Andankle Society (AOFAS) score and exudation at 12 months after operation were evaluated. RESULTS: Five patients were successfully completed operation without lower extremity vascular occlusion, and were followed up for 16 to 36 months. The wound healing time after internal fixation ranged from 16 to 26 days, and healing time of fractures ranged from 16 to 27 weeks. AOFAS score ranged from 65 to 91 at 12 months after operation, and 2 patients got excellent result, 2 good and 1 fair. Among them, 1 patient with skin ulcer on the back of foot caused by scalding at 5 months after operation (non-complication), was recovered after treatment;the wound leakage complication occurred in 2 patients, and were recovered after dressing change. No osteomyelitis or fracture occurred in all patients. CONCLUSION: Vancomycin calcium sulfate with internal fixation in treating calcaneal osteomyelitis secondary to calcaneal osteomyelitis caused by diabetic foot could not only control infection, but also promote fracture healing, and obtain good clinical results.


Asunto(s)
Calcáneo , Pie Diabético , Fijación Interna de Fracturas , Osteomielitis , Humanos , Masculino , Persona de Mediana Edad , Femenino , Osteomielitis/cirugía , Osteomielitis/tratamiento farmacológico , Osteomielitis/etiología , Pie Diabético/cirugía , Calcáneo/lesiones , Calcáneo/cirugía , Estudios Retrospectivos , Fijación Interna de Fracturas/métodos , Fracturas Óseas/complicaciones , Fracturas Óseas/cirugía
15.
J Phys Chem A ; 128(27): 5298-5306, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38917472

RESUMEN

The identification of the non-noble metal constituted TaO cluster as a potential analogue to the noble metal Au is significant for the development of tailored materials. It leverages the superatom concept to engineer properties with precision. However, the impact of incrementally integrating TaO units on the electronic configurations and properties within larger TaO-based clusters remains to be elucidated. By employing the density functional theory calculations, the global minima and low-lying isomers of the TanOn (n = 2-5) clusters were determined, and their structural evolution was disclosed. In the cluster series, Ta5O5 was found to possess the highest electron affinity (EA) with a value of 2.14 eV, based on which a dual external field (DEF) strategy was applied to regulate the electronic property of the cluster. Initially, the electron-withdrawing CO ligand was affixed to Ta5O5, followed by the application of an oriented external electric field (OEEF). The CO ligation was found to be able to enhance the Ta5O5 cluster's electron capture capability by adjusting its electron energy levels, with the EA of Ta5O5(CO)4 peaking at 2.58 eV. Subsequently, the introduction of OEEF further elevated the EA of the CO-ligated cluster. Notably, OEEF, when applied along the +x axis, was observed to sharply increase the EA to 3.26 eV, meeting the criteria for superhalogens. The enhancement of EA in response to OEEF intensity can be quantified as a functional relationship. This finding highlights the advantage of OEEF over conventional methods, demonstrating its capacity for precise and continuous modulation of cluster EAs. Consequently, this research has adeptly transformed tantalum oxide clusters into superhalogen structures, underscoring the effectiveness of the DEF strategy in augmenting cluster EAs and its promise as a viable tool for the creation of superhalogens.

16.
Cell Discov ; 10(1): 62, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38862506

RESUMEN

Membrane budding, which underlies fundamental processes like endocytosis, intracellular trafficking, and viral infection, is thought to involve membrane coat-forming proteins, including the most observed clathrin, to form Ω-shape profiles and helix-forming proteins like dynamin to constrict Ω-profiles' pores and thus mediate fission. Challenging this fundamental concept, we report that polymerized clathrin is required for Ω-profiles' pore closure and that clathrin around Ω-profiles' base/pore region mediates pore constriction/closure in neuroendocrine chromaffin cells. Mathematical modeling suggests that clathrin polymerization at Ω-profiles' base/pore region generates forces from its intrinsically curved shape to constrict/close the pore. This new fission function may exert broader impacts than clathrin's well-known coat-forming function during clathrin (coat)-dependent endocytosis, because it underlies not only clathrin (coat)-dependent endocytosis, but also diverse endocytic modes, including ultrafast, fast, slow, bulk, and overshoot endocytosis previously considered clathrin (coat)-independent in chromaffin cells. It mediates kiss-and-run fusion (fusion pore closure) previously considered bona fide clathrin-independent, and limits the vesicular content release rate. Furthermore, analogous to results in chromaffin cells, we found that clathrin is essential for fast and slow endocytosis at hippocampal synapses where clathrin was previously considered dispensable, suggesting clathrin in mediating synaptic vesicle endocytosis and fission. These results suggest that clathrin and likely other intrinsically curved coat proteins are a new class of fission proteins underlying vesicle budding and fusion. The half-a-century concept and studies that attribute vesicle-coat contents' function to Ω-profile formation and classify budding as coat-protein (e.g., clathrin)-dependent or -independent may need to be re-defined and re-examined by considering clathrin's pivotal role in pore constriction/closure.

17.
Chemistry ; 30(45): e202401886, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-38857119

RESUMEN

Chalcogen bond (ChB) catalysis, as a new type in the field of non-covalent bond catalysis, has become a hot research topic in the field of organocatalysis in recent years. In the present work, we investigated the catalytic performance of a series of hypervalent ChB catalysis based on the intramolecular Aza-Michael reaction of aminochalcone. The reaction includes the carbon-nitrogen bond coupling step (key step) and the proton transfer step. The catalytic performance of mono-dentate pentafluorophenyl chalcogen bond donor ChB1 was comparable to that of bis-dentate chalcogen bond donor ChB4, and stronger than that of mono-dentate chalcogen bond donors ChB2 and ChB3. The formation of the chalcogen bond between the catalyst and the carbonyl oxygen atom of the reactant, causing the charge rearrangement of the reactant and C(1) charge of the -C-Ph group to become more positive, thereby the ChB catalysis promoted the nucleophile reaction. The electron density of the chalcogen bond of the pre-complex, the most positive electrostatic potentials of the catalyst, and the NPA charge of the key atom are proportional to the Gibbs energy barrier of the C-N bond coupling process, which provides an idea to predict the catalytic activity of the ChB catalysis.

18.
BMC Psychol ; 12(1): 327, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38835103

RESUMEN

BACKGROUND AND RESEARCH OBJECTIVES: Given the enduring popularity of higher education, there has been considerable attention on the correlation between college students' engagement in sports and their academic stress levels. This study seeks to delve deeply into how university physical education fosters academic performance by influencing students' sports interests, particularly in enhancing their psychological resilience to mitigate academic pressure. Through this investigation, the aim is to offer both theoretical underpinnings and empirical evidence to support the holistic enhancement of higher education. RESEARCH METHODS: Initially, this study undertakes an analysis of the fundamental relationship between college students' physical activities and their experience of academic stress. Subsequently, utilizing a structural equation model, specific research models and hypotheses are formulated. These are then examined in detail through the questionnaire method to elucidate the mechanism by which college sports interests alleviate academic stress. RESEARCH FINDINGS: The study reveals a significant positive correlation between psychological resilience and academic stress, indicating that a robust psychological resilience can effectively diminish academic pressure. Furthermore, both the sports atmosphere and sports interest are found to exert a notable positive impact on academic stress, mediated by the variable of psychological toughness. This underscores the pivotal role of physical education in fostering positive psychological traits and enhancing academic achievement. CONCLUSION: This study underscores the central importance of cultivating and nurturing college students' sports interests, as well as fostering a conducive sports atmosphere, in fortifying psychological resilience and mitigating academic pressure. By offering novel perspectives and strategies for alleviating the academic stress faced by college students, this study contributes valuable theoretical insights and practical experiences to the broader development of higher education.


Asunto(s)
Resiliencia Psicológica , Deportes , Estrés Psicológico , Estudiantes , Humanos , Estrés Psicológico/psicología , Estudiantes/psicología , Estudiantes/estadística & datos numéricos , Masculino , Universidades , Deportes/psicología , Femenino , Adulto Joven , Adulto , Rendimiento Académico/psicología , Encuestas y Cuestionarios , Adolescente
19.
Cancer Gene Ther ; 31(7): 1034-1048, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38806621

RESUMEN

Acute myeloid leukemia (AML) is a malignant clonal hematopoietic disease with a poor prognosis. Understanding the interaction between leukemic cells and the tumor microenvironment (TME) can help predict the prognosis of leukemia and guide its treatment. Re-analyzing the scRNA-seq data from the CSC and G20 cohorts, using a Python-based pipeline including machine-learning-based scVI-tools, recapitulated the distinct hierarchical structure within the samples of AML patients. Weighted correlation network analysis (WGCNA) was conducted to construct a weighted gene co-expression network and to identify gene modules primarily focusing on hematopoietic stem cells (HSCs), multipotent progenitors (MPPs), and natural killer (NK) cells. The analysis revealed significant deregulation in gene modules associated with aerobic respiration and ribosomal/cytoplasmic translation. Cell-cell communications were elucidated by the CellChat package, revealing an imbalance of activating and inhibitory immune signaling pathways. Interception of genes upregulated in leukemic HSCs & MPPs as well as in NKG2A-high NK cells was used to construct prognostic models. Normal Cox and artificial neural network models based on 10 genes were developed. The study reveals the deregulation of mitochondrial and ribosomal genes in AML patients and suggests the co-occurrence of stimulatory and inhibitory factors in the AML TME.


Asunto(s)
Leucemia Mieloide Aguda , Microambiente Tumoral , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Microambiente Tumoral/genética , Microambiente Tumoral/inmunología , Pronóstico , Ribosomas/metabolismo , Ribosomas/genética , Mitocondrias/genética , Mitocondrias/metabolismo , Redes Reguladoras de Genes , Perfilación de la Expresión Génica/métodos , Genes Mitocondriales
20.
Materials (Basel) ; 17(9)2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38730890

RESUMEN

A modified 3D re-entrant honeycomb is designed and fabricated utilizing Laser Cladding Deposition (LCD) technology, the mechanical properties of which are systematically investigated by experimental and finite element (FE) methods. Firstly, the influences of honeycomb angle on localized deformation and the response of force are studied by an experiment. Experimental results reveal that the honeycomb angles have a significant effect on deformation and force. Secondly, a series of numerical studies are conducted to analyze stress characteristics and energy absorption under different angles (α) and velocities (v). It is evident that two variables play an important role in stress and energy. Thirdly, response surface methodology (RSM) and the Non-Dominated Sorting Genetic Algorithm II (NSGA-II) are implemented with high precision to solve multi-objective optimization. Finally, the final compromise solution is determined based on the fitness function, with an angle of 49.23° and an impact velocity of 16.40 m/s. Through simulation verification, the errors of energy absorption (EA) and peak crush stress (PCS) are 9.26% and 0.4%, respectively. The findings of this study offer valuable design guidance for selecting the optimal design parameters under the same mass conditions to effectively enhance the performance of the honeycomb.

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