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1.
Opt Lett ; 49(4): 1029-1032, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38359234

RESUMEN

Directional emission of electromagnetic waves plays an essential role in laser radar and free-space communication. For most directional antennas, bandwidth and miniaturization are a pair of contradictions due to their underlying interference mechanism. Connection-type metamaterials exhibit exotic electromagnetic response near zero-frequency, which relies on the global topology of mesh connectivity rather than resonance and thus has a broad working bandwidth. In this Letter, we investigate the broadband orientation-dependent coupling effect of a 3D double mesh metamaterial. Based on this effect, we achieve a broadband directional emission (relative bandwidth of 37.72%) using a compact structure (compared to twice working wavelength). Our work provides a novel, to the best of our knowledge, scheme to manipulate a long-wavelength wave and may pave the way to a miniaturized directional antenna.

2.
Artículo en Inglés | MEDLINE | ID: mdl-38619977

RESUMEN

A Gram-stain-negative, non-motile, and slightly halophilic alphaproteobacterium, designated strain EGI FJ00035T, was isolated from enrichment sediment samples of a saline lake in Xinjiang Uygur Autonomous Region, PR China. The taxonomic position of the isolate was determined using the polyphasic taxonomic and phylogenomic analyses. Phylogenetic analysis based on the 16S rRNA gene sequences indicated that strain EGI FJ00035T formed a distinct clade with 'Chelativorans alearense' UJN715 and 'Chelativorans xinjiangense' lm93 with sequence similarities of 98.44 and 98.22 %, respectively, while sharing less than 96.7 % with other valid type strains. The novel isolate could be distinguished from other species of the genus Chelativorans by its distinct phenotypic, physiological, and genotypic characteristics. Optimal growth of strain EGI FJ00035T occurred on marine agar 2216 at pH 7.0 and 30 °C. The major respiratory quinone was Q-10, while the major fatty acids (>5 %) were C19 : 0 cyclo ω8c, summed feature 8 (C17 : 1 ω6c and/or C17 : 1 ω7c), C16 : 0, C18 : 0, and iso-C17 : 0. The detected polar lipids included diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, unidentified aminophospholipids, unidentified glycolipids, and an unidentified lipid. Based on its genome sequence, the G+C content of strain EGI FJ00035T was 63.2 mol%. The average nucleotide identity, average amino acid identity, and digital DNA-DNA hybridization values of strain EGI FJ00035T against related members of the genus Chelativorans were below the thresholds for delineation of a novel species. According our polyphasic taxonomic data, strain EGI FJ00035T represents a new species of the genus Chelativorans, for which the name Chelativorans salis sp. nov. is proposed. The type strain of the proposed novel isolate is EGI FJ00035T (=KCTC 92251T=CGMCC 1.19480T).


Asunto(s)
Ácidos Grasos , Phyllobacteriaceae , Ácidos Grasos/química , Fosfolípidos/química , Ubiquinona/química , Filogenia , ARN Ribosómico 16S/genética , Lagos/análisis , Composición de Base , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genética , Análisis de Secuencia de ADN , China , Phyllobacteriaceae/genética
3.
BMC Nephrol ; 24(1): 361, 2023 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-38053041

RESUMEN

OBJECTIVE: Diabetic nephropathy (DN) is a serious chronic complication of diabetes mellitus (DM). Endoplasmic reticulum (ER) stress is an important factor in the regulation of pathological processes in DN, and excessive ER stress can lead to apoptosis. Although the IL-33/ST2 axis is known to be involved in diabetic kidney disease or related nephropathy, its role and molecular mechanisms remain poorly understood in terms of DN. The purpose of this study was to investigate the effects of IL-33/ST2 signaling on DN and to characterize the roles that ER stress and apoptosis play in DN. METHODS: To investigate this study, mice were randomly assigned into DN (induced by 0.1% STZ) and Control groups. Biochemical indices (FBG, BUN, UPR, UCE) were measured in serum and urine samples to reflect blood glucose and kidney damage. Quantitative real-time PCR, western blot, and immunofluorescence were used to assess gene and protein expression of the IL-33/ST2 axis and ER stress relative signaling molecule. Apoptosis was analyzed by flow cytometry. RESULTS: IL-33 levels are significantly increased in the kidneys of patients and mice with DN. Double immunofluorescence staining showed that IL-33 colocalized with CD31-positive endothelial cells. Treatment with IL-33 attenuated kidney injury in Streptozotocin (STZ)-treated mice. In vitro, we showed that IL-33 attenuated ER stress and apoptosis in glomerular endothelial cells. However, sST2 treatment significantly reversed these effects of IL-33. CONCLUSION: Together, these data suggest that IL-33/ST2 signaling mitigates STZ-induced renal damage, partly at least, by suppressing ER stress and apoptosis. Therefore, IL-33 may be an effective therapeutic target in DN.


Asunto(s)
Diabetes Mellitus Experimental , Nefropatías Diabéticas , Ratas , Humanos , Ratones , Animales , Nefropatías Diabéticas/patología , Células Endoteliales/metabolismo , Interleucina-33/farmacología , Interleucina-33/uso terapéutico , Proteína 1 Similar al Receptor de Interleucina-1 , Ratas Sprague-Dawley , Diabetes Mellitus Experimental/metabolismo , Estrés del Retículo Endoplásmico , Apoptosis
4.
J Magn Reson Imaging ; 55(6): 1864-1874, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34545977

RESUMEN

BACKGROUND: Partial bile duct ligation (PBDL) model is a reliable cholestatic fibrosis experimental model that showed complex histopathological changes. Magnetic resonance imaging (MRI) features of PBDL have not been well characterized. PURPOSE: To investigate the potential of MRI parameters in assessing fibrosis in PBDL and explore the relationships between MRI and pathological features. ANIMAL MODEL: Established PBDL models. POPULATION: Fifty-four mice were randomly divided into four timepoints PBDL groups and one sham group. FIELD STRENGTH/SEQUENCE: 3.0 T; MRI sequences included T1-weighted fast spin-echo (FSE), T2-weighted single shot FSE, variable flip angle T1 mapping, multi-echo SE T2 mapping, multi-echo gradient-echo T2* mapping, and multi-b-value diffusion-weighted imaging. ASSESSMENT: MRI examination was performed at the corresponding timepoints after surgery. Native T1, ΔT1 (T1native-T1post), T2, T2*, apparent diffusion coefficient (ADC) values, histogram parameters (skewness and kurtosis), intravoxel incoherent motion parameters (f, D, and D* ) within the entire ligated (PBDL), non-ligated liver (PBDL), and whole liver (sham) were obtained. Fibrosis and inflammation were assessed in Masson and H&E staining slices using the Metavir and activity scoring system. STATISTICAL TESTS: One-way ANOVA, Spearman's rank correlation, and receiver operating characteristic curves were performed. P < 0.05 was considered statistically significant. RESULTS: Fibrosis and inflammation were finally staged as F3 and A3 in ligated livers but were not observed in non-ligated or sham livers. Ligated livers displayed significantly elevated native T1, ΔT1, T2, and reduced ADC and T2* than other livers. Spearman's correlation showed better correlation with inflammation (r = 0.809) than fibrosis (r = 0.635) in T2 and both ΔT1 and ADC showed stronger correlation with fibrosis (r = 0.704 and r = -0.718) than inflammation (r = 0.564 and r = -0.550). Area under the curve (AUC) for ΔT1 performed the highest (0.896). When combined with all relative parameters, AUC increased to 0.956. DATA CONCLUSION: Multiparametric MRI can evaluate and differentiate pathological changes in PBDL. ΔT1 and ADC better correlated with fibrosis while T2 stronger with inflammation. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY: Stage 2.


Asunto(s)
Imágenes de Resonancia Magnética Multiparamétrica , Animales , Conductos Biliares/diagnóstico por imagen , Conductos Biliares/cirugía , Imagen de Difusión por Resonancia Magnética , Modelos Animales de Enfermedad , Fibrosis , Humanos , Inflamación/diagnóstico por imagen , Imagen por Resonancia Magnética , Ratones , Estudios Prospectivos
5.
Bull Entomol Res ; 112(4): 536-545, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35199636

RESUMEN

Athetis lepigone Möschler (Lepidoptera, Noctuidae) is a common maize pest in Europe and Asia. However, there is no long-term effective management strategy is available yet to suppress its population. Adults rely heavily on olfactory cues to locate their optimal host plants and oviposition sites. Pheromone-binding proteins (PBPs) are believed to be responsible for recognizing and transporting different odorant molecules to interact with receptor membrane proteins. In this study, the ligand-binding specificities of two AlepPBPs (AlepPBP2 and AlepPBP3) for sex pheromone components and host plant (maize) volatiles were measured by fluorescence ligand-binding assay. The results demonstrated that AlepPBP2 had a high affinity with two pheromones [(Z)-7-dodecenyl acetate, Ki = 1.11 ± 0.1 µM, (Z)-9-tetradecenyl acetate, Ki = 1.32 ± 0.15 µM] and ten plant volatiles, including (-)-limonene, α-pinene, myrcene, linalool, benzaldehyde, nonanal, 2-hexanone, 3-hexanone, 2-heptanone and 6-methyl-5-hepten-2-one. In contrast, we found that none of these chemicals could bind to AlepPBP3. Our results clearly show no significant differences in the functional characterization of the binding properties between AlepPBP2 and AlepPBP3 to sex pheromones and host plant volatiles. Furthermore, molecular docking was employed for further detail on some crucial amino acid residues involved in the ligand-binding of AlepPBP2. These findings will provide valuable information about the potential protein binding sites necessary for protein-ligand interactions which appear as attractive targets for the development of novel technologies and management strategies for insect pests.


Asunto(s)
Mariposas Nocturnas , Receptores Odorantes , Atractivos Sexuales , Animales , Proteínas Portadoras/metabolismo , Femenino , Proteínas de Insectos/metabolismo , Ligandos , Simulación del Acoplamiento Molecular , Mariposas Nocturnas/metabolismo , Feromonas/metabolismo , Receptores Odorantes/metabolismo , Atractivos Sexuales/metabolismo , Zea mays/metabolismo
6.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(12): 1311-1312, 2022 Dec 15.
Artículo en Zh | MEDLINE | ID: mdl-36544409

RESUMEN

This article reports a case of incomplete Kawasaki disease with no response to intravenous immunoglobulin (IVIG). A girl, aged 1 year, had the symptoms of fever, rash, finger desquamation, and coronary artery ectasia. She still had fever at 36 hours after the first dose of IVIG treatment, and her temperature returned to normal after the second dose of IVIG treatment. The follow-up after 1 month showed that the coronary artery diameter returned to normal. This article summarizes the experience in the treatment of incomplete Kawasaki disease with no response to IVIG in order to reduce the incidence of coronary artery damage.


Asunto(s)
Aneurisma Coronario , Síndrome Mucocutáneo Linfonodular , Humanos , Femenino , Lactante , Inmunoglobulinas Intravenosas/uso terapéutico , Síndrome Mucocutáneo Linfonodular/complicaciones , Síndrome Mucocutáneo Linfonodular/tratamiento farmacológico , Síndrome Mucocutáneo Linfonodular/diagnóstico , Fiebre , Aneurisma Coronario/etiología , Estudios Retrospectivos
7.
Zhongguo Zhong Yao Za Zhi ; 46(20): 5194-5200, 2021 Oct.
Artículo en Zh | MEDLINE | ID: mdl-34738419

RESUMEN

Arisaematis Rhizoma included in the Chinese Pharmacopoeia is the dried tuber of Arisaema erubescens, A. heterophyllum or A. amurense in the family Araceae. This paper mainly focuses on the classification and summary of the chemical components and structures reported in recent years in the above three varieties of this medicinal material included in the pharmacopoeia, including alkaloids, flavonoids, phenylpropanoids, lignans and benzene ring derivatives, steroids and terpenes, glycosides and esters, etc. Then we reviewed the reported biological activities of these chemical components, including cytotoxicity, antitumor activity, antibacterial activity, nematicidal activity, etc. Although there have been reports on the review of the chemical composition of the medicinal material, the structure and classification of the chemical composition in these reviews are not clear enough. This review provides a basis for the later study of the chemical composition of this medicinal material, especially the identification of the chemical structures. And most of the current reviews on the biological activity of this medicinal material are mainly for the crude extract. This paper mainly summarized the biological activity of related monomer compounds and expected to lay a foundation for the development of novel high-efficiency and low-toxicity active leading compounds from Arisaematis Rhizoma.


Asunto(s)
Arisaema , Medicamentos Herbarios Chinos , Medicamentos Herbarios Chinos/farmacología , Flavonoides , Glicósidos , Rizoma
8.
Opt Express ; 27(18): 24900-24913, 2019 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-31510371

RESUMEN

In this study, a perovskite is integrated with an ultra-thin Cu/Cu2O (CCO) composite film, a transparent material with high mobility, to achieve a double-side and low-voltage operable photodetector. Compared to photodetectors that utilize metal electrode with perovskite, the use of CCO significantly enhances the photocurrent (from nA up to mA). It acts as a large-scale hole transport layer. The photodetector exhibits high responsivities of 6.79 AW-1 [illuminated via the fluorine-doped tin oxide (FTO) side] and 10.23 AW-1 (illuminated via CCO side). The detectivities obtained at both illuminated sides are as high as over 1011 Jones. Additionally, the Cu/Cu2O-covered perovskite effectively prevents the reaction of perovskite in the interface. This work reveals that the perovskite/CCO heterojunction photodetector can be considered a promising candidate for applications in bifacial-illuminated and flexible/wearable optoelectronic technologies.

9.
Phys Chem Chem Phys ; 20(47): 29959-29968, 2018 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-30478461

RESUMEN

Nanomaterials have excellent adsorption performance, which mainly depends on the adsorption thermodynamics that is related to the shape of the nanoparticles that make up the nanomaterial, but the effects of shape on the thermodynamics of adsorption are not fully clear. In this paper, theoretically, the general formulae of adsorption thermodynamic properties for nanoparticles with different shapes and different sizes were derived, and the influencing regularities and mechanisms on adsorption thermodynamic properties were discussed. Experimentally, the influences of the shape and size of nano-CeO2 on the thermodynamics of adsorption were studied in aqueous solution. The experiment results showed that the shape has significant influences on the thermodynamics of adsorption, and the smaller the particle size, the more significant the effects of shape on the thermodynamics. For the adsorption of nano-CeO2 with different shapes and the same equivalent particle size, compared with the sphere, the equilibrium constant of adsorption for the octahedron is larger, while the molar Gibbs free energy of adsorption , the molar adsorption enthalpy of adsorption and the molar adsorption entropy of adsorption are smaller. For the adsorption of nano-CeO2 with the same shape, with the decreasing particle size, increases, while , and decrease; and , , and are each linearly related to the reciprocal of particle size. The experimental results are consistent with the theoretical relations. The theories can quantitatively describe the adsorption behavior on nanoparticles, explain the regularities and mechanisms of influence of shape, and provide guidance for the research and application of nanoadsorption.

10.
Mol Cancer ; 16(1): 111, 2017 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-28659173

RESUMEN

BACKGROUND: Recent evidences showed that long noncoding RNAs (lncRNAs) are frequently dysregulated and play important roles in various cancers. Clear cell renal cell carcinoma (ccRCC) is one of the leading cause of cancer-related death, largely due to the metastasis of ccRCC. However, the clinical significances and roles of lncRNAs in metastatic ccRCC are still unknown. METHODS: lncRNA expression microarray analysis was performed to search the dysregulated lncRNA in metastatic ccRCC. quantitative real-time PCR was performed to measure the expression of lncRNAs in human ccRCC samples. Gain-of-function and loss-of-function experiments were performed to investigate the biological roles of lncRNAs on ccRCC cell proliferation, migration, invasion and in vivo metastasis. RNA pull-down, RNA immunoprecipitation, chromatin immunoprecipitation, and western blot were performed to explore the molecular mechanisms underlying the functions of lncRNAs. RESULTS: The microarray analysis identified a novel lncRNA termed metastatic renal cell carcinoma-associated transcript 1 (MRCCAT1), which is highly expressed in metastatic ccRCC tissues and associated with the metastatic properties of ccRCC. Multivariate Cox regression analysis revealed that MRCCAT1 is an independent prognostic factor for ccRCC patients. Overexpression of MRCCAT1 promotes ccRCC cells proliferation, migration, and invasion. Depletion of MRCCAT1 inhibites ccRCC cells proliferation, migration, and invasion in vitro, and ccRCC metastasis in vivo. Mechanistically, MRCCAT1 represses NPR3 transcription by recruiting PRC2 to NPR3 promoter, and subsequently activates p38-MAPK signaling pathway. CONCLUSIONS: MRCCAT1 is a critical lncRNA that promotes ccRCC metastasis via inhibiting NPR3 and activating p38-MAPK signaling. Our results imply that MRCCAT1 could serve as a prognostic biomarker and therapeutic target for ccRCC.


Asunto(s)
Carcinoma de Células Renales/patología , Neoplasias Renales/patología , ARN Largo no Codificante/genética , Receptores del Factor Natriurético Atrial/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Anciano , Animales , Carcinoma de Células Renales/genética , Carcinoma de Células Renales/metabolismo , Carcinoma de Células Renales/mortalidad , Línea Celular Tumoral , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Renales/genética , Neoplasias Renales/metabolismo , Neoplasias Renales/mortalidad , Masculino , Ratones Endogámicos BALB C , Persona de Mediana Edad , Pronóstico , Regiones Promotoras Genéticas , Receptores del Factor Natriurético Atrial/genética , Transducción de Señal , Ensayos Antitumor por Modelo de Xenoinjerto , Proteínas Quinasas p38 Activadas por Mitógenos/genética
11.
Int J Antimicrob Agents ; : 107262, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38945178

RESUMEN

PURPOSE: Polymyxin B, with its unique structure and mechanism of action, has emerged as a key therapeutic agent against Gram-negative bacteria. The study aims to explore potential factors to influence its effectiveness and safety. METHODS: A Model-Based Meta-Analysis (MBMA) of 96 articles was conducted, focusing on factors like dosage, bacterial species, and combined antibiotic therapy. The analysis evaluated mortality rates and incidence rate of renal dysfunction, also employing parametric survival models to assess 30-day survival rates. RESULTS: In the study involving 96 articles and 9,716 patients, polymyxin B's daily dose showed minimal effect on overall mortality, with high-dose group mortality at 33.57% (95% CI: 29.15-38.00) compared to the low-dose group at 35.44% (95% CI: 28.99-41.88), p=0.64. Mortality significantly varied by bacterial species, with Pseudomonas aeruginosa infections at 58.50% (95% CI: 55.42-63.58). Monotherapy exhibited the highest mortality at 40.25% (95% CI: 34.75-45.76), p<0.01. Renal dysfunction was more common in high-dose patients at 29.75% (95% CI: 28.52-30.98), with no significant difference across antibiotic regimens, p=0.54. The 30-day Overall Survival rate for monotherapy therapy was 63.6% (95% CI: 59.3-67.5) and 70.2% (95% CI: 64.4-76.2) for association therapy with ß-lactam drugs. CONCLUSIONS: The dosage of Polymyxin B doesn't significantly change death rates, but its effectiveness varies based on the bacterial infection. Certain bacteria like Pseudomonas aeruginosa are associated with higher mortality. Combining Polymyxin B with other antibiotics, especially ß-lactam drugs, improves survival rates. Side effects depend on the dose, with lower doses being safer. These findings emphasize the importance of customizing treatment to balance effectiveness and safety.

12.
Plant Physiol Biochem ; 210: 108572, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38677189

RESUMEN

The Tetratricopeptide repeat (TPR)-like superfamily with TPR conserved domains is widely involved in the growth and abiotic stress in many plants. In this report, the gene MdTPR16 belongs to the TPR family in apple (Malus domestica). Promoter analysis reveal that MdTPR16 incorporated various stress response elements, including the drought stress response elements. And different abiotic stress treatments, drought especially, significantly induce the response of MdTPR16. Overexpression of MdTPR16 result in better drought tolerance in apple and Arabidopsis by up-regulating the expression levels of drought stress-related genes, achieving a higher chlorophyll content level, more material accumulation, and overall better growth compared to WT in the drought. Under drought stress, the overexpressed MdTPR16 also mitigate the oxidative damage in cells by reducing the electrolyte leakage, malondialdehyde content, and the H2O2 and O2- accumulation in apples and Arabidopsis. In conclusion, MdTPR16 act as a beneficial regulator of drought stress response by regulating the expression of related genes and the cumulation of reactive oxygen species (ROS).


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Malus , Proteínas de Plantas , Malus/genética , Malus/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sequías , Arabidopsis/genética , Arabidopsis/metabolismo , Estrés Fisiológico/genética , Plantas Modificadas Genéticamente/genética , Repeticiones de Tetratricopéptidos/genética , Especies Reactivas de Oxígeno/metabolismo
13.
Bioresour Technol ; 400: 130700, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38615969

RESUMEN

To improve nitrogen removal efficiency (NRE) and achieve homogenous distribution of anammox sludge and substrate, a new substrate equalization theory and a cumulative overload index was proposed for multifed upflow anaerobic sludge bed (MUASB) reactors with mature anammox granules. The performance and flow patterns of MUASB reactors were investigated under various influent conditions. The results showed that the nitrogen removal performance and stability of MUASB reactors could be optimized by minimizing the cumulative load. The NRE gradually increased from 83.3 ± 2.2 %, 86.8 ± 4.2 % to 89.3 ± 4.1 % and 89.7 ± 1.6 % in feeding flow tests and feeding port tests, respectively. Furthermore, the flow patterns were compared based on residence time distribution and computational fluid dynamics, indicating that a better equilibrium distribution of microorganisms and substrates could be achieved in the MUASB reactors under the lowest cumulative load. Therefore, substrate equalization theory can be used to optimize the nitrogen removal performance of MUASB reactors with low-carbon footprints.


Asunto(s)
Reactores Biológicos , Nitrógeno , Aguas del Alcantarillado , Aguas del Alcantarillado/microbiología , Anaerobiosis , Nitrógeno/metabolismo , Oxidación-Reducción , Hidrodinámica
14.
Minerva Endocrinol (Torino) ; 48(2): 160-171, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-33103870

RESUMEN

BACKGROUND: Polycystic ovary syndrome (PCOS) is a complex endocrine disorder with well-established metabolic abnormalities. In the present study, untargeted metabolomics technology was applied to analyze the serum and follicular fluid samples from women with polycystic ovary syndrome and healthy controls using 1H nuclear magnetic resonance (NMR). METHODS: Seventy samples for PCOS analysis were collected in hospital of Shandong University of Traditional Chinese Medicine (Jinan, China), NMR was used as analytical technology and multivariate analysis was applied to analyze metabolomics difference in PCOS and healthy controls. RESULTS: Significant metabolic differences were found in both serum and follicular fluid samples with orthogonal partial least-squares discriminant analysis (OPLS-DA). Three discriminated metabolites (1-Methylhistidine, threonine and Citrate) in both serum and follicular fluid were altered in PCOS patients. Abnormal energy metabolism, lipid metabolism and amino acid metabolism were detected in PCOS patients. Furthermore, more significantly changed amino acids were discovered in follicular fluid samples. CONCLUSIONS: Our findings would provide a resource for further investigations on metabolic disturbance in PCOS patients.


Asunto(s)
Síndrome del Ovario Poliquístico , Humanos , Femenino , Síndrome del Ovario Poliquístico/metabolismo , Síndrome del Ovario Poliquístico/patología , Líquido Folicular/metabolismo , Metabolómica , Espectroscopía de Resonancia Magnética , Aminoácidos/metabolismo
15.
Neural Regen Res ; 18(3): 582-586, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36018181

RESUMEN

Spinal cord injury is a severe and devastating disease, and spasticity is a common and severe complication that is notoriously refractory to treatment. However, the pathophysiological mechanisms underlying spasticity and its development remain largely unknown. The goal of the present study was to find differences, if any, in metabolites of the left precentral gyrus and basal ganglia of patients who have spinal cord injury with or without spasticity, and to explore the relationship between the brain metabolite concentrations and clinical status. Thirty-six participants were recruited for magnetic resonance spectroscopic examination: 23 with spinal cord injury (12 with spasticity and 11 without spasticity) and 13 healthy controls. We acquired localized proton spectra from the precentral gyrus and basal ganglia via 10 mm3 voxels. Notably, univariate linear regression analysis demonstrated that the lower that the N-acetylaspartate concentration (a marker for neuronal loss) was in the precentral gyrus of the patients, the lower their ASIA (American Spinal Injury Association) light-touch scores, pinprick scores, and motor scores. Additionally, longer durations of injury were associated with higher N-acetylaspartate levels in the precentral gyrus. Compared with the healthy participants and patients without spasticity, N-acetylaspartate levels in the patients with spasticity were significantly lower in both the precentral gyrus and basal ganglia. Lower N-acetylaspartate levels also correlated with greater sensory and motor dysfunction in the patients who had spinal cord injury with spasticity.

16.
Neural Regen Res ; 18(4): 750-755, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36204831

RESUMEN

The inability of damaged neurons to regenerate within the mature central nervous system (CNS) is a significant neuroscientific challenge. Astrocytes are an essential component of the CNS and participate in many physiological processes including blood-brain barrier formation, axon growth regulation, neuronal support, and higher cognitive functions such as memory. Recent reprogramming studies have confirmed that astrocytes in the mature CNS can be transformed into functional neurons. Building on in vitro work, many studies have demonstrated that astrocytes can be transformed into neurons in different disease models to replace damaged or lost cells. However, many findings in this field are controversial, as the source of new neurons has been questioned. This review summarizes progress in reprogramming astrocytes into neurons in vivo in animal models of spinal cord injury, brain injury, Huntington's disease, Parkinson's disease, Alzheimer's disease, and other neurodegenerative conditions.

17.
Front Neurorobot ; 16: 1072887, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36531921

RESUMEN

Modern air defense battlefield situations are complex and varied, requiring high-speed computing capabilities and real-time situational processing for task assignment. Current methods struggle to balance the quality and speed of assignment strategies. This paper proposes a hierarchical reinforcement learning architecture for ground-to-air confrontation (HRL-GC) and an algorithm combining model predictive control with proximal policy optimization (MPC-PPO), which effectively combines the advantages of centralized and distributed approaches. To improve training efficiency while ensuring the quality of the final decision. In a large-scale area air defense scenario, this paper validates the effectiveness and superiority of the HRL-GC architecture and MPC-PPO algorithm, proving that the method can meet the needs of large-scale air defense task assignment in terms of quality and speed.

18.
Dalton Trans ; 51(9): 3734-3739, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-35166737

RESUMEN

The mechanism of Au(I)-catalyzed intermolecular annulation of 2-(1-alkynyl)-2-alken-1-one with N-allenamide was carefully elucidated using density functional theory (DFT). The reaction is initiated by the binding of the Au(I) catalyst with 2-(1-alkynyl)-2-alken-1-one rather than with N-allenamide. The key intermediate, a gold all-carbon 1,3-dipole species, is revealed to be more reactive than the gold allylic carbocation. The influence of ligands and substituents was rationally analyzed. We believe that our study will provide deeper mechanistic insights into the chemoselective reactions of alkynes with N-allenamide.

19.
Sci Rep ; 12(1): 21014, 2022 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-36470922

RESUMEN

Partial bile duct ligation (pBDL) is considered a well-tolerated cholestatic model. Magnetic resonance imaging (MRI) is one of the most widely used tools in noninvasive imaging. However, no systematic studies have reported the possible effects of repeated MRI assessments in the pBDL model. Sixty BALB/C mice were investigated. MRI images of each mouse were recorded once every 2 weeks for 6 weeks after pBDL or sham surgery. The reproducibility of the pBDL model and the reliability of MRI were examined by behavioral, physiological, biochemical, and pathological parameters. The mice showed no alterations on behavioral and physiological tests (P > 0.05) at 2, 4, and 6 weeks after pBDL. Repeated general anesthesia did not result in any impairment after pBDL (P > 0.05). The behavioral and biochemical parameters were not affected by repeated MRIs or repeated contrast-enhanced MRIs (P > 0.05). Pathological staining showed the homogeneous formation of collagenous fiber in the pBDL mice and did not indicate any influence of repeated contrast-enhanced MRI on the number of inflammatory cells or fibrotic formation (P > 0.05). Thus, pBDL is a reproducible model with many advantages for animal welfare and scientific research. Additionally, MRI, as a safe tool for longitudinal evaluation and is well tolerated in mice with cholestasis.


Asunto(s)
Conductos Biliares , Colestasis , Ratones , Animales , Reproducibilidad de los Resultados , Ratones Endogámicos BALB C , Conductos Biliares/diagnóstico por imagen , Conductos Biliares/cirugía , Conductos Biliares/patología , Colestasis/diagnóstico por imagen , Colestasis/patología , Ligadura/métodos , Imagen por Resonancia Magnética , Modelos Animales de Enfermedad , Hígado/patología
20.
Front Neurosci ; 16: 1065897, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36590290

RESUMEN

Introduction: Spinal cord injury (SCI) often causes continuous neurological damage to clinical patients. Circular RNAs (circRNAs) are related to a lot of diseases, including SCI. We previously found five candidate circRNAs which were likely to regulate the secondary pathophysiological changes in rat model after traumatic SCI. Methods: In this study, we first selected and overexpressed target circRNA in rats. We then explored its functional roles using various functional assays in a rat model after SCI. Results: We found that rno-circRNA-013017-the selected target circRNA-reduced neuron apoptosis, preserved the survival and activity of motor neurons, and regulated apoptosis-related proteins at 3 days post-SCI using western blot, immunofluorescence and polymerase chain reaction. Additionally, we found that rno-circRNA-013017 inhibited descending axonal degeneration and preserved motor neurons and descending axons at 6 weeks post-SCI using immunofluorescence, biotin dextran amine diffusion tensor imaging. Finally, the overexpression of rno-circRNA-013017 promoted the locomotor function of rats after SCI using open-field test and gait analysis. Conclusion: Focusing on the functions of rno-circRNA-013017, this study provides new options for future studies exploring therapeutic targets and molecular mechanisms for SCI.

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