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1.
Medicine (Baltimore) ; 103(33): e39146, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39151524

RESUMEN

RATIONALE: Anti-Myelin oligodendrocyte glycoprotein (MOG) and anti-metabotropic glutamate receptor 5 (mGluR5) double antibody positive encephalitis characterized by optic neuritis is extremely rare. We present a case of overlapping syndrome of MOG-IgG-associated disease and anti-mGluR5 encephalitis manifested as optic neuritis. PATIENT CONCERNS: A 60-year-old Chinses woman presented to the hospital with progressive vision loss and headache for 1 week. The cerebrospinal fluid examination was within the normal range. Visual evoked potentials study disclosed prolonged latency of P100 bilaterally. Fundus examination revealed indistinct boundaries of both optic discs. Her brain magnetic resonance imaging showed patchy hyperintensity in the posterior horn of the left ventricle and the left optic nerve. Her serum was positive for anti-MOG and anti-mGluR5 antibodies. DIAGNOSIS: The patient was diagnosed with overlapping syndrome of anti-MOG antibody-associated disease and anti-mGluR5 encephalitis mainly based on the clinical symptoms and further test of the antibody in serum. INTERVENTIONS AND OUTCOMES: She was subsequently subjected to empirical treatment with intravenous methylprednisolone. After discharge, she was given a tapering dose of oral prednisone, alongside mycophenolate mofetil. On outpatient follow-up, her symptoms showed no relapse after 1 month, and her condition remained stable. LESSONS: Early recognition of autoimmune encephalitis is crucial. The detection of cerebrospinal fluid and serum of autoimmune encephalitis and demyelinating diseases of the CNS, including MOG-IgG and mGluR5-IgG, should be strengthened in order to make a precise diagnosis and develop a comprehensive treatment plan in a timely manner.


Asunto(s)
Autoanticuerpos , Glicoproteína Mielina-Oligodendrócito , Neuritis Óptica , Receptor del Glutamato Metabotropico 5 , Humanos , Femenino , Neuritis Óptica/diagnóstico , Neuritis Óptica/inmunología , Neuritis Óptica/tratamiento farmacológico , Persona de Mediana Edad , Glicoproteína Mielina-Oligodendrócito/inmunología , Autoanticuerpos/sangre , Encefalitis/diagnóstico , Encefalitis/inmunología , Encefalitis/tratamiento farmacológico , Metilprednisolona/uso terapéutico , Imagen por Resonancia Magnética , Síndrome
2.
BMC Med Imaging ; 24(1): 187, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39054448

RESUMEN

OBJECTIVE: There are two major issues in the MRI image diagnosis task for Parkinson's disease. Firstly, there are slight differences in MRI images between healthy individuals and Parkinson's patients, and the medical field has not yet established precise lesion localization standards, which poses a huge challenge for the effective prediction of Parkinson's disease through MRI images. Secondly, the early diagnosis of Parkinson's disease traditionally relies on the subjective judgment of doctors, which leads to insufficient accuracy and consistency. This article proposes an improved YOLOv5 detection algorithm based on deep learning for predicting and classifying Parkinson's images. METHODS: This article improves the YOLOv5s network as the basic framework. Firstly, the CA attention mechanism was introduced to enable the model to dynamically adjust attention based on local features of the image, significantly enhancing the sensitivity of the model to PD related small pathological features; Secondly, replace the dynamic full dimensional convolution module to optimize the multi-level extraction of image features; Finally, the coupling head strategy is adopted to improve the execution efficiency of classification and localization tasks separately. RESULTS: We validated the effectiveness of the proposed method using a dataset of 582 MRI images from 108 patients. The results show that the proposed method achieves 0.961, 0.974, and 0.986 in Precision, Recall, and mAP, respectively, and the experimental results are superior to other algorithms. CONSLUSION: The improved model has achieved high accuracy and detection accuracy, and can accurately detect and recognize complex Parkinson's MRI images. SIGNIFICANCE: This algorithm has shown good performance in the early diagnosis of Parkinson's disease and can provide clinical assistance for doctors in early diagnosis. It compensates for the limitations of traditional methods.


Asunto(s)
Aprendizaje Profundo , Imagen por Resonancia Magnética , Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/diagnóstico por imagen , Enfermedad de Parkinson/clasificación , Imagen por Resonancia Magnética/métodos , Algoritmos , Femenino , Masculino , Interpretación de Imagen Asistida por Computador/métodos , Anciano , Persona de Mediana Edad , Diagnóstico Precoz
3.
Inorg Chem ; 63(31): 14623-14629, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39038226

RESUMEN

Chalcopyrite copper-indium-gallium diselenides (CIGS) have emerged as promising materials with remarkable electronic properties and potential applicability to high-efficiency solar cells. The crystal and electronic structures of CIGS can be continuously tuned from their initial states under pressure. Although pressure-induced band gap closure in CIGS has been predicted in extensive theoretical studies, it has not been supported by experimental evidence. Here, we comprehensively investigate the pressure-dependent optical, electronic, and structural properties of Cu(In0.7Ga0.3)Se2 up to 42.6 GPa. Our experimental results reveal an irreversible electronic transition from the semiconducting to the metallic state at 14.3 GPa. Under compression, the Cu(In0.7Ga0.3)Se2 structure evolves from a tetragonal I4̅2d phase to an orthorhombic Pna21 phase, which has not been previously reported in chalcopyrite. More intriguingly, the Pna21 phase is irreversible and possesses smaller Cu-Se and In/Ga-Se bond lengths and a smaller Cu-Se-Cu bond angle than the I4̅2d phase. Density functional theory calculations indicate a lower enthalpy of the Pna21 phase than that of the I4̅2d phase at pressures above 10.6 GPa. Meanwhile, density of states calculations illustrate that metallization arises from the overlap of the Se p and Cu d orbitals as the bond length reduces. This pressure-induced behavior could facilitate the development of novel devices with various phenomena involving strong coupling of the mechanical, electrical, and optical properties of chalcopyrite.

4.
Emerg Microbes Infect ; 13(1): 2337677, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38578315

RESUMEN

Previously, we reported a cohort of Japanese encephalitis (JE) patients with Guillain-Barré syndrome. However, the evidence linking Japanese encephalitis virus (JEV) infection and peripheral nerve injury (PNI) remains limited, especially the epidemiology, clinical presentation, diagnosis, treatment, and outcome significantly differ from traditional JE. We performed a retrospective and multicenter study of 1626 patients with JE recorded in the surveillance system of the Chinese Center for Disease Control and Prevention, spanning the years 2016-2020. Cases were classified into type 1 and type 2 JE based on whether the JE was combined with PNI or not. A comparative analysis was conducted on demographic characteristics, clinical manifestations, imaging findings, electromyography data, laboratory results, and treatment outcomes. Among 1626 laboratory confirmed JE patients, 230 (14%) were type 2 mainly located along the Yellow River in northwest China. In addition to fever, headache, and disturbance of consciousness, type 2 patients experienced acute flaccid paralysis of the limbs, as well as severe respiratory muscle paralysis. These patients presented a greater mean length of stay in hospital (children, 22 years [range, 1-34]; adults, 25 years [range, 0-183]) and intensive care unit (children, 16 years [range, 1-30]; adults, 17 years [range, 0-102]). The mortality rate was higher in type 2 patients (36/230 [16%]) compared to type 1 (67/1396 [5%]). The clinical classification of the diagnosis of JE may play a crucial role in developing a rational treatment strategy, thereby mitigating the severity of the disease and potentially reducing disability and mortality rates among patients.

5.
bioRxiv ; 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38585977

RESUMEN

Glycosylation affects many vital functions of organisms. Therefore, its surveillance is critical from basic science to biotechnology, including biopharmaceutical development and clinical diagnostics. However, conventional glycan structure analysis faces challenges with throughput and cost. Lectins offer an alternative approach for analyzing glycans, but they only provide glycan epitopes and not full glycan structure information. To overcome these limitations, we developed LeGenD, a lectin and AI-based approach to predict N-glycan structures and determine their relative abundance in purified proteins based on lectin-binding patterns. We trained the LeGenD model using 309 glycoprofiles from 10 recombinant proteins, produced in 30 glycoengineered CHO cell lines. Our approach accurately reconstructed experimentally-measured N-glycoprofiles of bovine Fetuin B and IgG from human sera. Explanatory AI analysis with SHapley Additive exPlanations (SHAP) helped identify the critical lectins for glycoprofile predictions. Our LeGenD approach thus presents an alternative approach for N-glycan analysis.

6.
Acta Histochem ; 126(1): 152135, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38266318

RESUMEN

BACKGROUND: Alzheimer's disease (AD) is a complex, multifactorial neurodegenerative disease. However, the pathogenesis remains unclear. Recently, an increasing number of studies have demonstrated that ferroptosis is a new type of iron-dependent programmed cell death, contributes to the death of nerve cells in AD. By controlling iron homeostasis and mitochondrial function, the particular protein called frataxin (FXN), which is situated in the mitochondrial matrix, is a critical regulator of ferroptosis disease. It is encoded by the nuclear gene FXN. Here, we identified a novel underlying mechanism through which ferroptosis mediated by FXN contributes to AD. METHODS: Human neuroblastoma cells (SH-SY5Y) were injured by L-glutamate (L-Glu). Overexpression of FXN by lentiviral transfection. In each experimental group, we assessed the ultrastructure of the mitochondria, the presence of iron and intracellular Fe2 + , the levels of reactive oxygen species, the mitochondrial membrane potential (MMP), and lipid peroxidation. Quantification was done for malondialdehyde (MDA) and reduced glutathione (GSH), as well as reactive oxygen species (ROS). Western blot and cellular immunofluorescence assays were used to detect the expression of xCT and GPX4 proteins which in System Xc-/GPX4 pathway, and the protein expressions of ACSL4 and TfR1 were investigated by Western blot. RESULTS: The present work showed: (1) The expression of FXN was reduced in the L-Glu group; (2) Compared with the Control group, MMP was reduced in the L-Glu group, and mitochondria were observed to shrink and cristae were deformed, reduced or disappeared by transmission electron microscopy, and after FXN overexpression and ferrostatin-1 (Fer-1) (10 µmol/L) intervened, MMP was increased and mitochondrial morphology was significantly improved, suggesting that mitochondrial function was impaired in the L-Glu group, and overexpression of FXN could improve the manifestation of mitochondrial function impairment. (3) In the L-Glu group, ROS, MDA, iron ion concentration and Fe2+ levels were increased, GSH was decreased. Elevated expression of ACSL4 and TfR1, important regulatory proteins of ferroptosis, was detected by Western blot, and the expression of xCT and GPX4 in the System Xc-/GPX4 pathway was reduced by Western blot and cellular immunofluorescence. However, the above results were reversed when FXN overexpression and Fer-1 intervened. CONCLUSION: To conclude, our research demonstrates that an elevated expression of FXN effectively demonstrates a robust neuroprotective effect against oxidative damage induced by L-Glu. Moreover, it mitigates mitochondrial dysfunction and lipid metabolic dysregulation associated with ferroptosis. FXN overexpression holds promise in potential therapeutic strategies for AD by inhibiting ferroptosis in nerve cells and fostering their protection.


Asunto(s)
Ferroptosis , Frataxina , Enfermedades Neurodegenerativas , Humanos , Ciclohexilaminas , Frataxina/metabolismo , Ácido Glutámico , Hierro , Enfermedades Neurodegenerativas/metabolismo , Fenilendiaminas , Especies Reactivas de Oxígeno
7.
J Alzheimers Dis ; 97(2): 909-926, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38160355

RESUMEN

BACKGROUND: Structural magnetic resonance imaging (sMRI) is vital for early Alzheimer's disease (AD) diagnosis, though confirming specific biomarkers remains challenging. Our proposed Multi-Scale Self-Attention Network (MUSAN) enhances classification of cognitively normal (CN) and AD individuals, distinguishing stable (sMCI) from progressive mild cognitive impairment (pMCI). OBJECTIVE: This study leverages AD structural atrophy properties to achieve precise AD classification, combining different scales of brain region features. The ultimate goal is an interpretable algorithm for this method. METHODS: The MUSAN takes whole-brain sMRI as input, enabling automatic extraction of brain region features and modeling of correlations between different scales of brain regions, and achieves personalized disease interpretation of brain regions. Furthermore, we also employed an occlusion sensitivity algorithm to localize and visualize brain regions sensitive to disease. RESULTS: Our method is applied to ADNI-1, ADNI-2, and ADNI-3, and achieves high performance on the classification of CN from AD with accuracy (0.93), specificity (0.82), sensitivity (0.96), and area under curve (AUC) (0.95), as well as notable performance on the distinguish of sMCI from pMCI with accuracy (0.85), specificity (0.84), sensitivity (0.74), and AUC (0.86). Our sensitivity masking algorithm identified key regions in distinguishing CN from AD: hippocampus, amygdala, and vermis. Moreover, cingulum, pallidum, and inferior frontal gyrus are crucial for sMCI and pMCI discrimination. These discoveries align with existing literature, confirming the dependability of our model in AD research. CONCLUSION: Our method provides an effective AD diagnostic and conversion prediction method. The occlusion sensitivity algorithm enhances deep learning interpretability, bolstering AD research reliability.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Enfermedad de Alzheimer/patología , Reproducibilidad de los Resultados , Imagen por Resonancia Magnética/métodos , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Algoritmos , Disfunción Cognitiva/diagnóstico
8.
Front Immunol ; 14: 1293425, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38111582

RESUMEN

Autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy and low-flow perimedullary arteriovenous fistulas (PMAVFs) may cause longitudinal widespread myelopathy. We report a middle-aged male patient with autoimmune GFAP astrocytopathy complicated with low flow PMAVFs disease, presenting with lower extremity weakness and dysuria. Magnetic resonance imaging (MRI) of the spinal cord revealed a significant longitudinal extent of T2 high signal from T11 to L1, with the lesion located proximal to the vascular territory supplied by the anterior spinal artery. Multiple patchy abnormal signals were seen adjacent to the anterior and posterior horns of the lateral ventricles bilaterally and at the centers of the semi-ovals on MRI of the cranial brain, with iso signal in T1Flair, the high signal in T2WI, and no high signal seen in Diffusion Weighted Imaging (DWI). Subsequently, the presence of anti-GFAP antibodies was detected in the cerebrospinal fluid (CSF), and the diagnosis of autoimmune GFAP astrocytopathy in conjunction with low-flow PMAVFs was confirmed through spinal digital subtraction angiography (DSA). This case report aims to increase neurologists' awareness of this disease and avoid missed or misdiagnosed cases that may lead to delayed treatment.


Asunto(s)
Fístula Arteriovenosa , Enfermedades de la Médula Espinal , Humanos , Masculino , Persona de Mediana Edad , Fístula Arteriovenosa/diagnóstico por imagen , Fístula Arteriovenosa/complicaciones , Encéfalo , Proteína Ácida Fibrilar de la Glía , Enfermedades de la Médula Espinal/etiología
9.
Front Neurol ; 14: 1242472, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37780700

RESUMEN

Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease characterized by progressive degeneration of upper and lower motor neurons, with occasional involvement of the extrapyramidal system. Mutations in the sigma non-opioid intracellular receptor 1 (SIGMAR1) gene have been identified as one of the causes of ALS. Here, we present a case of a 49-year-old man diagnosed with ALS-Parkinson's disease (PD) complex. The patient exhibited bradykinesia and tremor, and whole-exome sequencing revealed homozygous mutations in the SIGMAR1 gene (c.446-2A > T). In addition, we conducted an investigation into the clinical and molecular phenotype of previously reported variants of SIGMAR1 associated with ALS. This case report aims to raise awareness among physicians regarding atypical phenotypes of amyotrophic lateral sclerosis and to encourage further research on the factors leading to SIGMAR1 mutations in patients.

10.
Int Immunopharmacol ; 124(Pt B): 111040, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37839277

RESUMEN

Autophagy regulates many cell function related to cancer, including cell proliferation, invasion and apoptosis. Therefore, we investigated the potential value of crosstalk between autophagy and apoptosis. The present study demonstrated that seven autophagy related genes were screened from the biological network of salidroside (Sal) acting on liver cancer. The GO analysis showed that these genes were mainly involved in apoptosis and autophagy. The KEGG analysis showed that these genes regulated the process of liver cancer through Th17 cell differentiation, PI3K-Akt signaling pathway and other pathways. Moreover, seven genes were positively correlated with tumor purity, number of B cells, number of CD4+ T cells, number of CD8+ T cells, number of macrophages, number of dendritic cells and number of neutrophils. The overall survival time of liver cancer patients in the high expression group of BIRC5, HSP90AB1 and MTOR was lower than that in the low expression group (P < 0.05), while the overall survival time of the liver cancer patients in the high expression group of DLC1 and FOXO1 was higher than that in the low expression group (P < 0.05). In the pan-cancer analysis, we also found that BIRC5, HSP90AB1, MTOR, and ITGA6 were highly expressed in various cancers, while DLC1, FOXO1, and FOS were low expressed in various cancers. In the molecule docking analysis, we found that FOS, HSP90AB1, and MTOR had the best binding ability. Notably, in the vitro validation experiments, Sal was confirmed to induce autophagy and apoptosis, inhibite invasion and metastasis of liver cancer cells through the PI3K/Akt/mTOR signaling pathway. Meanwhile, inhibition of autophagy by chloroquine diphosphate (CQ) promoted Sal-induced mitochondrial apoptosis via corresponding cell and animal experiments. We speculated that Sal-induced autophagy might be a protective mechanism, inhibition of autophagy could further promote the progression of liver cancer. It may provide important insight into the molecular mechanism of crosstalk between autophagy and apoptosis, and provide a new theoretical basis of Sal combined with autophagy inhibitors as a adjuvant chemotherapeutic strategy for human liver cancer.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animales , Humanos , Neoplasias Hepáticas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Carcinoma Hepatocelular/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Linfocitos T CD8-positivos/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Apoptosis/fisiología , Autofagia/fisiología , Proliferación Celular , Proteínas Activadoras de GTPasa , Proteínas Supresoras de Tumor
11.
Int J Neurosci ; : 1-6, 2023 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-37881832

RESUMEN

HEADINGS: Kelch-like protein 11antibody is a recently identified biomarker for paraneoplastic neurological syndromes associated with germ-cell tumors that was first described as an onconeural antibody causing autoimmune encephalitis associated with seminoma in 2019. Ataxia is the most prevalent presenting symptom, with other neurological symptoms including vertigo, double vision, hearing loss, tinnitus and dysarthria. Magnetic resonance imaging scans reveal that the lesions are mostly located in the cerebellum and brainstem, particularly in the pontine region, and may also exhibit cerebellar atrophy. AIM OF THE STUDY: In this study, we report the clinical features of Kelch-like protein 11 antibody-associated paraneoplastic neurological syndrome. MATERIALS AND METHODS: We present a middle-aged female patient who presented with vertigo, cognitive decline, ataxia and limb weakness. A cell-based assay (CBA) showed positive IgG Kelch-like protein 11 in both her serum and CSF, as well as positive oligoclonal bands in her CSF. She was diagnosed with KLHL11 antibody-associated autoimmune encephalomyelitis and received high-dose intravenous methylprednisolone pulse therapy. RESULT AND CONCLUSIONS: Clinical outcomes suggest that patients with Kelch-like protein 11 antibody mostly have poor prognoses, excepting our case. We propose that early and appropriate treatments are critical for timely diagnosis and rapid improvement.

12.
Cell Death Differ ; 30(11): 2432-2445, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37828085

RESUMEN

Ferroptosis is a type of cell death characterized by the accumulation of intracellular iron and an increase in hazardous lipid peroxides. Ferroptosis and autophagy are closely related. Ionizing radiation is a frequently used cancer therapy to kill malignancies. We found that ionizing radiation induces both ferroptosis and autophagy and that there is a form of mutualism between the two processes. Ionizing radiation also causes lipid droplets to form in proximity to damaged mitochondria, which, through the action of mitophagy, results in the degradation of the peridroplet mitochondria by lysosomes and the consequent release of free fatty acids and a significant increase in lipid peroxidation, thus promoting ferroptosis. Ionizing radiation has a stronger, fatal effect on cells with a high level of mitophagy, and this observation suggests a novel strategy for tumor treatment.


Asunto(s)
Ferroptosis , Neoplasias , Humanos , Ácidos Grasos no Esterificados/farmacología , Mitofagia , Hierro/metabolismo , Neoplasias/metabolismo , Peroxidación de Lípido , Radiación Ionizante , Especies Reactivas de Oxígeno/metabolismo
13.
Neurol India ; 71(4): 716-724, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37635504

RESUMEN

We sought to evaluate whether the neuromelanin-sensitive magnetic resonance imaging (NM-MRI) features of the substantia nigra (SN) have utility in the differential diagnosis of Parkinson's disease (PD) and essential tremor (ET). This study enrolled 23 patients with PD, 20 patients with ET, and 18 healthy participants. All subjects underwent clinical examination, motor and cognitive assessments, and NM-MRI scans. The area and contrast-to-noise ratio (CNR) values of SN were defined according to NM-MRI images. Then, receiver operating characteristic (ROC) analysis was conducted to characterize the diagnostic power of the SN area and CNR values of SN. Compared with ET and control groups, the PD group showed a significant reduction of the area of SN (P = 0.003, PD vs. ET; P = 0.001, PD vs. control) and in the SN to midbrain area ratio in the same layer (P = 0.006, PD vs. ET; P = 0.005, PD vs. control). The SN area had a sensitivity of 65% and a specificity of 87% for distinguishing ET from PD, with an area under the curve (AUC) of 0.7630 and a Youden index of 0.5200, whereas the ratio of the SN area to midbrain area in the same layer had a sensitivity of 60% and a specificity of 87% for distinguishing ET from PD, with an AUC of 0.7478 and a Youden index of 0.4700. Compared with the ET group, the mean CNR value of the SN and the respective CNR values of the three subregions were all weakened in the PD group, and only the CNR in the middle part was significantly different from the control group (P = 0.006). The sensitivity of the CNR value of the middle part of the SN for differentiating ET from PD was 65%, the specificity was 87%, the AUC was 0.7500, and the Youden index was 0.5200.Based on our findings, we conclude that NM-MRI can improve diagnostic accuracy in PD and can be used as a specific and sensitive potential diagnostic biomarker for PD.


Asunto(s)
Temblor Esencial , Enfermedad de Parkinson , Humanos , Diagnóstico Diferencial , Enfermedad de Parkinson/diagnóstico por imagen , Enfermedad de Parkinson/patología , Temblor Esencial/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos
14.
J Intell Mater Syst Struct ; 34(14): 1688-1701, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37521728

RESUMEN

This article presents a tunable multi-stable piezoelectric energy harvester. The apparatus consists of a stationary magnet and a cantilever beam whose free end is attached by an assembly of two cylindrical magnets that can be moved along the beam and a small cylindrical magnet that is fixed at the beam tip. By varying two parameters, the system can assume three stability states: tri-stable, bi-stable, and mono-stable, respectively. The developed apparatus is used to validate two models for the magnetic restoring force: the equivalent magnetic point dipole approach and the equivalent magnetic 2-point dipole approach. The study focuses on comparing the accuracy of the two models for a wide range of the tuning parameters. The restoring forces of the apparatus are determined dynamically and compared with their analytical counterparts based on each of the models. To improve the model accuracy, a model optimization is carried out by using the multi-population genetic algorithm. With the optimum models, the parametric sensitivity of each of the models is investigated. The stability state region is generated by using the optimum second model.

15.
Cell Death Discov ; 9(1): 267, 2023 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-37507394

RESUMEN

Radiotherapy is an important cancer treatment strategy that causes DNA damage in tumor cells either directly or indirectly. Autophagy is a physiological process linked to DNA damage. Mitophagy is a form of autophagy, which specifically targets and eliminates impaired mitochondria, thereby upholding cellular homeostasis. However, the connection between DNA damage and mitophagy has yet to be fully elucidated. We found that mitophagy, as an upstream signal, increases ionizing radiation-induced DNA damage by downregulating or overexpressing key mitophagy proteins Parkin and BNIP3. Enhancing the basal level of mitophagy in conjunction with X-ray irradiation can potentially diminish cell cycle arrest at the G2/M phase, substantially elevate the accumulation of γ-H2AX, 53BP1, and PARP1 foci within the nucleus, augment DNA damage, and facilitate the demise of tumor cells. Consequently, this approach prolongs the survival of melanoma-bearing mice. The findings of this study are anticipated to offer a therapeutic approach for enhancing the therapeutic effectiveness of radiotherapy.

16.
Nature ; 618(7966): 712-715, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37286602

RESUMEN

The most massive and shortest-lived stars dominate the chemical evolution of the pre-galactic era. On the basis of numerical simulations, it has long been speculated that the mass of such first-generation stars was up to several hundred solar masses1-4. The very massive first-generation stars with a mass range from 140 to 260 solar masses are predicted to enrich the early interstellar medium through pair-instability supernovae (PISNe)5. Decades of observational efforts, however, have not been able to uniquely identify the imprints of such very massive stars on the most metal-poor stars in the Milky Way6,7. Here we report the chemical composition of a very metal-poor (VMP) star with extremely low sodium and cobalt abundances. The sodium with respect to iron in this star is more than two orders of magnitude lower than that of the Sun. This star exhibits very large abundance variance between the odd- and even-charge-number elements, such as sodium/magnesium and cobalt/nickel. Such peculiar odd-even effect, along with deficiencies of sodium and α elements, are consistent with the prediction of primordial pair-instability supernova (PISN) from stars more massive than 140 solar masses. This provides a clear chemical signature indicating the existence of very massive stars in the early universe.

17.
BMC Med Educ ; 23(1): 341, 2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37193976

RESUMEN

BACKGROUND: To investigate the use of flipped classroom pedagogy based on "Internet plus" in teaching viral hepatitis in the lemology course during the COVID-19 epidemic. METHODS: This study included students from the clinical medicine general practitioner class at Nanjing Medical University's Kangda College, with the observation group consisting of 67 students from the 2020-2021 school year and the control group consisting of 70 students from the 2019-2020 school year. The observation group used "Internet plus" flipped classroom pedagogy, while the control group used conventional offline instruction. The theory course and case analysis ability scores from the two groups were compared and analyzed, and questionnaire surveys were administered to the observation group. RESULT: After the flipped classroom, the observation group had significantly higher theoretical test scores (38.62 ± 4.52) and case analysis ability scores (21.08 ± 3.58) than the control group (37.37 ± 2.43) (t = 2.024, P = 0.045) and (19.16 ± 1.15) (t = 4.254, P < 0.001), respectively. The questionnaire survey in the observation group revealed that the "Internet plus" flipped classroom pedagogy approach can help enhance students' enthusiasm to learn, clinical thinking ability, practical application ability, and learning efficiency, with satisfaction rates of 81.7%, 85.0%, 83.3%, and 78.8%, respectively; 89.4% of students expressed hope that whenever physical classes resumed, the offline courses could be combined with this pedagogy approach. CONCLUSION: The use of the "Internet plus" flipped classroom pedagogy technique for teaching viral hepatitis in a lemology course boosted students' theory learning ability as well as their case analysis ability. The majority of students were pleased with this type of instruction and hoped that whenever physical classes resumed, the offline courses may be integrated with the "Internet plus" flipped classroom pedagogical approach.


Asunto(s)
COVID-19 , Estudiantes de Enfermería , Humanos , Aprendizaje Basado en Problemas/métodos , Aprendizaje , Examen Físico , Curriculum , Enseñanza
18.
J Virol ; 97(6): e0026823, 2023 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-37191520

RESUMEN

African swine fever virus (ASFV), the cause of a highly contagious hemorrhagic and fatal disease of domestic pigs, has a complex multilayer structure. The inner capsid of ASFV located underneath the inner membrane enwraps the genome-containing nucleoid and is likely the assembly of proteolytic products from the virally encoded polyproteins pp220 and pp62. Here, we report the crystal structure of ASFV p150△NC, a major middle fragment of the pp220 proteolytic product p150. The structure of ASFV p150△NC contains mainly helices and has a triangular plate-like shape. The triangular plate is approximately 38 Šin thickness, and the edge of the triangular plate is approximately 90 Šlong. The structure of ASFV p150△NC is not homologous to any of the known viral capsid proteins. Further analysis of the cryo-electron microscopy maps of the ASFV and the homologous faustovirus inner capsids revealed that p150 or the p150-like protein of faustovirus assembles to form screwed propeller-shaped hexametric and pentametric capsomeres of the icosahedral inner capsids. Complexes of the C terminus of p150 and other proteolytic products of pp220 likely mediate interactions between the capsomeres. Together, these findings provide new insights into the assembling of ASFV inner capsid and provide a reference for understanding the assembly of the inner capsids of nucleocytoplasmic large DNA viruses (NCLDV). IMPORTANCE African swine fever virus has caused catastrophic destruction to the pork industry worldwide since it was first discovered in Kenya in 1921. The architecture of ASFV is complicated, with two protein shells and two membrane envelopes. Currently, mechanisms involved in the assembly of the ASFV inner core shell are less understood. The structural studies of the ASFV inner capsid protein p150 performed in this research enable the building of a partial model of the icosahedral ASFV inner capsid, which provides a structural basis for understanding the structure and assembly of this complex virion. Furthermore, the structure of ASFV p150△NC represents a new type of fold for viral capsid assembly, which could be a common fold for the inner capsid assembly of nucleocytoplasmic large DNA viruses (NCLDV) and would facilitate the development of vaccine and antivirus drugs against these complex viruses.


Asunto(s)
Virus de la Fiebre Porcina Africana , Cápside , Modelos Moleculares , Ensamble de Virus , Animales , Fiebre Porcina Africana/virología , Virus de la Fiebre Porcina Africana/química , Virus de la Fiebre Porcina Africana/metabolismo , Virus de la Fiebre Porcina Africana/ultraestructura , Cápside/química , Cápside/metabolismo , Cápside/ultraestructura , Microscopía por Crioelectrón , Sus scrofa , Cristalografía por Rayos X , Estructura Terciaria de Proteína
19.
Brain Behav ; 13(3): e2926, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36806734

RESUMEN

BACKGROUND: Propranolol, a nonselective beta-adrenergic blocker, has long been used as one of the standard treatments for essential tremor (ET). Repetitive transcranial magnetic stimulation (rTMS) has also been used for a long time as a substitution therapy for ET patients. OBJECTIVE: The main aim of this study was to evaluate the antitremor effect of 1-Hz (low-frequency) cerebellar rTMS and compare it to the use of propranolol in ET patients. METHODS: In this single-blinded, randomized, controlled pilot study, a total of 38 patients with ET were randomized into two groups. One group (n = 20) received 1200 pulses of 1-Hz rTMS at an intensity of 90% of the resting motor threshold to the bilateral cerebellar region for 10 days. Another group (n = 18) received oral propranolol for 30 days. The initial dose was 30 mg/day, which was increased to 60 mg/day after 5 days, then to 90 mg/day on the 11th day, and continued thereafter for 20 days. The Fahn-Tolosa-Marin (FTM) clinical scale was assessed at baseline and at days 5, 10, and 30 to evaluate tremor severity, specific motor tasks, and functional disability. RESULTS: Low-frequency rTMS of the cerebellum significantly improved tremor severity, specific motor tasks (writing, spiral drawing, and pouring), and FTM total scores on days 10 and 30. Nevertheless, we found no significant difference in functional disability at any point in time (p > .05). There were no statistically significant differences in FTM Part A, Part B, Part C scores and total scores of patients in propranolol group on days 5 and 10 compared with before treatment (p > .05). However, FTM total scores and FTM Part A, Part B, and Part C scores were significantly improved for patients when the dose of propranolol was 90 mg/day on day 30. Our study showed that there was no statistically significant difference in the total FTM scores and FTM Part A, Part B, and Part C scores between rTMS and propranolol on days 5, 10, and 30 (p > .05). CONCLUSION: We conclude that both cerebellar low-frequency rTMS and propranolol could be effective treatment options for patients with ET, but it is not clear which method is more effective.


Asunto(s)
Temblor Esencial , Humanos , Temblor Esencial/tratamiento farmacológico , Estimulación Magnética Transcraneal/métodos , Propranolol/farmacología , Propranolol/uso terapéutico , Temblor , Cerebelo , Resultado del Tratamiento
20.
Mini Rev Med Chem ; 23(13): 1341-1359, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36200242

RESUMEN

Immunotherapy has been increasingly used in the treatment of cancer. Compared with chemotherapy, immunotherapy relies on the autoimmune system with fewer side effects. Small molecule immune-oncological medicines usually have good bioavailability, higher tissue and tumor permeability, and a reasonable half-life. In this work, we summarize the current advances in the field of small molecule approaches in tumor immunology, including small molecules in clinical trials and preclinical studies, containing PD1/PD-L1 small molecule inhibitors, IDO inhibitor, STING activators, RORγt agonists, TGF-ß inhibitors, etc. PD-1/DP-L1 is the most attractive target at present. Some small molecule drugs are being in clinical trial studies. Among them, CA-170 has attracted much attention as an oral small molecule drug. IDO is another popular target after PD-1/PDL1. The dual IDO and PD-1 inhibitor can improve the low response of PD-1 and has a good synergistic effect. STING is a protein that occurs naturally in the human body and can enhance the body's immunity. RORγt is mainly expressed in cells of the immune system. It promotes the differentiation of Th17 cells and produces the key factor IL-17, which plays a key role in the development of autoimmune diseases. TGFß signaling exhibits potent immunosuppressive activity on the coordinate innate and adaptive immunity, impairing the antitumor potential of innate immune cells in the tumor microenvironment. It is worth mentioning that immunotherapy drugs can often achieve better effects when used in combination, which will help defeat cancer.


Asunto(s)
Neoplasias , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares , Humanos , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/uso terapéutico , Receptor de Muerte Celular Programada 1 , Neoplasias/tratamiento farmacológico , Factores Inmunológicos , Inmunoterapia , Microambiente Tumoral
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