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1.
Cell ; 158(6): 1309-1323, 2014 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-25215489

RESUMEN

The balance between oxidative and nonoxidative glucose metabolism is essential for a number of pathophysiological processes. By deleting enzymes that affect aerobic glycolysis with different potencies, we examine how modulating glucose metabolism specifically affects hematopoietic and leukemic cell populations. We find that a deficiency in the M2 pyruvate kinase isoform (PKM2) reduces the levels of metabolic intermediates important for biosynthesis and impairs progenitor function without perturbing hematopoietic stem cells (HSCs), whereas lactate dehydrogenase A (LDHA) deletion significantly inhibits the function of both HSCs and progenitors during hematopoiesis. In contrast, leukemia initiation by transforming alleles putatively affecting either HSCs or progenitors is inhibited in the absence of either PKM2 or LDHA, indicating that the cell-state-specific responses to metabolic manipulation in hematopoiesis do not apply to the setting of leukemia. This finding suggests that fine-tuning the level of glycolysis may be explored therapeutically for treating leukemia while preserving HSC function.


Asunto(s)
Glucólisis , Hematopoyesis , Leucemia/metabolismo , Animales , Eliminación de Gen , Células Madre Hematopoyéticas/metabolismo , Humanos , Isoenzimas/metabolismo , L-Lactato Deshidrogenasa/metabolismo , Lactato Deshidrogenasa 5 , Ratones , Ratones Congénicos , Ratones Endogámicos C57BL , Piruvato Quinasa/genética , Piruvato Quinasa/metabolismo
2.
Plant Cell ; 2023 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-37795677

RESUMEN

Plant inflorescence architecture is determined by inflorescence meristem (IM) activity and controlled by genetic mechanisms associated with environmental factors. In Arabidopsis (Arabidopsis thaliana), TERMINAL FLOWER1 (TFL1) is expressed in the IM and is required to maintain indeterminate growth, whereas LEAFY (LFY) is expressed in the floral meristems (FMs) formed at the periphery of the IM and is required to activate determinate floral development. Here, we address how Arabidopsis indeterminate inflorescence growth is determined. We show that the 26S proteasome subunit REGULATORY PARTICLE AAA-ATPASE 2a (RPT2a) is required to maintain the indeterminate inflorescence architecture in Arabidopsis. rpt2a mutants display reduced TFL1 expression levels and ectopic LFY expression in the IM and develop a determinate zigzag-shaped inflorescence. We further found that RPT2a promotes DNA METHYLTRANSFERASE1 degradation, leading to DNA hypomethylation upstream of TFL1 and high TFL1 expression levels in the wild-type IM. Overall, our work reveals that proteolytic input into the epigenetic regulation of TFL1 expression directs inflorescence architecture in Arabidopsis, adding an additional layer to stem cell regulation.

3.
Differentiation ; 135: 100742, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38104501

RESUMEN

Hepatic organoids might provide a golden opportunity for realizing precision medicine in various hepatic diseases. Previously described hepatic organoid protocols from pluripotent stem cells rely on complicated multiple differentiation steps consisting of both 2D and 3D differentiation procedures. Therefore, the spontaneous formation of hepatic organoids from 2D monolayer culture is associated with a low-throughput production, which might hinder the standardization of hepatic organoid production and hamper the translation of this technology to the clinical or industrial setting. Here we describe the stepwise and fully 3D production of hepatic organoids from human pluripotent stem cells. We optimized every differentiation step by screening for optimal concentrations and timing of differentiation signals in each differentiation step. Hepatic organoids are stably expandable without losing their hepatic functionality. Moreover, upon treatment of drugs with known hepatotoxicity, we found hepatic organoids are more sensitive to drug-induced hepatotoxicity compared with 2D hepatocytes differentiated from PSCs, making them highly suitable for in vitro toxicity screening of drug candidates. The standardized fully 3D protocol described in the current study for producing functional hepatic organoids might serve as a novel platform for the industrial and clinical translation of hepatic organoid technology.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas , Células Madre Pluripotentes Inducidas , Células Madre Pluripotentes , Humanos , Diferenciación Celular/genética , Organoides
4.
New Phytol ; 242(3): 1098-1112, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38515249

RESUMEN

The potential for totipotency exists in all plant cells; however, the underlying mechanisms remain largely unknown. Earlier findings have revealed that the overexpression of LEAFY COTYLEDON 2 (LEC2) can directly trigger the formation of somatic embryos on the cotyledons of Arabidopsis. Furthermore, cotyledon cells that overexpress LEC2 accumulate significant lipid reserves typically found in seeds. The precise mechanisms and functions governing lipid accumulation in this process remain unexplored. In this study, we demonstrate that WRINKLED1 (WRI1), the key regulator of lipid biosynthesis, is essential for somatic embryo formation, suggesting that WRI1-mediated lipid biosynthesis plays a crucial role in the transition from vegetative to embryonic development. Our findings indicate a direct interaction between WRI1 and LEC2, which enhances the enrichment of LEC2 at downstream target genes and stimulates their induction. Besides, our data suggest that WRI1 forms a complex with LEC1, LEC2, and FUSCA3 (FUS3) to facilitate the accumulation of auxin and lipid for the somatic embryo induction, through strengthening the activation of YUCCA4 (YUC4) and OLEOSIN3 (OLE3) genes. Our results uncover a regulatory module controlled by WRI1, crucial for somatic embryogenesis. These findings provide valuable insights into our understanding of plant cell totipotency.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas , Ácidos Indolacéticos , Lípidos , Semillas/genética , Factores de Transcripción/metabolismo
5.
Plant Cell ; 33(6): 1907-1926, 2021 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-33730150

RESUMEN

Seed size is a major factor determining crop yields that is controlled through the coordinated development of maternal and zygotic tissues. Here, we identified Arabidopsis MATERNAL EFFECT EMBRYO ARREST45 (MEE45) as a B3 transcription factor that controls cell proliferation and maternally regulates seed size through its transcriptional activation of AINTEGUMENTA (ANT) and its downstream control of auxin biosynthesis in the ovule integument. After characterizing reduced seed and organ size phenotypes in mee45 mutants and finding that overexpression of MEE45 causes oversized seeds, we discovered that the MEE45 protein can bind to the promoter region of the ANT locus and positively regulate its transcription. ANT in-turn activates the expression of auxin biosynthetic genes (e.g. YUCCA4) in the ovule integument. Our results thus illustrate mechanisms underlying maternal tissue-mediated regulation of seed size and suggest that MEE45 and its downstream components can be harnessed to develop higher-yielding crop varieties.


Asunto(s)
Proteínas de Arabidopsis/genética , Arabidopsis/metabolismo , Ácidos Indolacéticos/metabolismo , Semillas/crecimiento & desarrollo , Factores de Transcripción/genética , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proliferación Celular/genética , Regulación de la Expresión Génica de las Plantas , Herencia Materna/genética , Oxigenasas de Función Mixta/genética , Oxigenasas de Función Mixta/metabolismo , Tamaño de los Órganos , Óvulo Vegetal/citología , Óvulo Vegetal/genética , Células Vegetales , Plantas Modificadas Genéticamente , Semillas/genética , Factores de Transcripción/metabolismo
6.
Opt Lett ; 49(17): 4891-4894, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39207990

RESUMEN

We experimentally demonstrate a liquid crystal (LC)-integrated EIT metasurface for active THz polarization conversion and asymmetric transmission. By controlling the LC orientation under static magnetic field anchoring and an adjustable electric field, the device realizes the active control from the OFF state to the ON state, corresponding to the orthogonal polarization excitation modes of the EIT metasurface. Furthermore, based on the different polarization responses at forward and backward incidences, we achieve asymmetric transmission at the EIT peak and two nearby resonances, with its isolation actively manipulated by the external electric field. This study on dynamic polarization conversion and asymmetric transmission by a LC-integrated metasurface offers a promising route for active THz devices, applicable to THz communication, switching, and sensing systems.

7.
J Magn Reson Imaging ; 59(3): 954-963, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37312270

RESUMEN

BACKGROUND: Gamma-aminobutyric acid (GABA) is an inhibitory neurotransmitter in human brains, playing a role in the pathogenesis of various psychiatric disorders. Current methods have some non-neglectable shortcomings and noninvasive and accurate detection of GABA in human brains is long-term challenge. PURPOSE: To develop a pulse sequence capable of selectively detecting and quantifying the 1 H signal of GABA in human brains based on optimal controlled spin singlet order. STUDY TYPE: Prospective. SUBJECTS/PHANTOM: A phantom of GABA (pH = 7.3 ± 0.1) and 11 healthy subjects (5 females and 6 males, body mass index: 21 ± 3 kg/m2 , age: 25 ± 4 years). FIELD STRENGTH/SEQUENCE: 7 Tesla, 3 Tesla, GABA-targeted magnetic resonance spectroscopy (GABA-MRS-7 T, GABA-MRS-3 T), magnetization prepared two rapid acquisition gradient echoes sequence. ASSESSMENT: By using the developed pulse sequences applied on the phantom and healthy subjects, the signals of GABA were successfully selectively probed. Quantification of the signals yields the concentration of GABA in the dorsal anterior cingulate cortex (dACC) in human brains. STATISTICAL TESTS: Frequency. RESULTS: The 1 H signals of GABA in the phantom and in the human brains of healthy subjects were successfully detected. The concentration of GABA in the dACC of human brains was 3.3 ± 1.5 mM. DATA CONCLUSION: The developed pulse sequences can be used to selectively probe the 1 H MR signals of GABA in human brains in vivo. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY STAGE: 1.


Asunto(s)
Encéfalo , Imagen por Resonancia Magnética , Masculino , Femenino , Humanos , Adulto Joven , Adulto , Estudios Prospectivos , Espectroscopía de Resonancia Magnética/métodos , Ácido gamma-Aminobutírico
8.
J Magn Reson Imaging ; 2024 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-38236785

RESUMEN

BACKGROUND: Quantitative in-situ pH mapping of gliomas is important for therapeutic interventions, given its significant association with tumor progression, invasion, and metastasis. Although chemical exchange saturation transfer (CEST) offers a noninvasive way for pH imaging based on the pH-dependent exchange rate (ksw ), the reliable quantification of ksw in glioma remains constrained due to technical challenges. PURPOSE: To quantify the pH of gliomas by measuring the proton exchange rate through optimized omega plot analysis. STUDY TYPE: Prospective. PHANTOMS/ANIMAL MODEL/SUBJECTS: Creatine and murine brain lysates phantoms, six rats with glioma xenograft model, and three patients with World Health Organization grade 2-4 gliomas. FIELD STRENGTH/SEQUENCE: 11.7 T, 7.0 T, CEST imaging, T2 -weighted (T2 W) imaging, and T1 -mapping. ASSESSMENT: Omega plot analysis, quasi-steady-state (QUASS) analysis, multi-pool Lorentzian fitting, amine and amide concentration-independent detection, pH enhanced method with the combination of amide and guanidyl (pHenh ), and magnetization transfer ratio (MTR) were utilized for pH metric quantification. The clinical outcomes were determined through radiologic follow-up and histopathological analysis. STATISTICAL TESTS: Mann-Whitney U test was performed to compare glioma with normal tissue, and Pearson's correlation analysis was used to assess the relationship between ksw and other parameters. RESULTS: In vitro experiments reveal that the determined ksw at 2 ppm increases exponentially with pH (creatine phantoms: ksw = 106 + 0.147 × 10(pH-4.198) ; lysates: ksw = 185.1 + 0.101 × 10(pH-3.914) ). Omega plot analysis exhibits a linear correlation between 1/MTRRex and 1/ω1 2 in the glioma xenografts (R2 > 0.98) and glioma patients (R2 > 0.99). The exchange rate in the rat glioma decreases compared to the contralateral normal tissue (349.46 ± 30.40 s-1 vs. 403.54 ± 51.01 s-1 , P = 0.025), while keeping independence from changes in concentration (r = 0.5037, P = 0.095). Similar pattern was observed in human data. DATA CONCLUSION: Utilizing QUASS-based, spillover-, and MT-corrected omega plot analysis for the measurement of exchange rates, offers a feasible method for quantifying pH within glioma. LEVEL OF EVIDENCE: NA TECHNICAL EFFICACY: Stage 1.

9.
Acta Pharmacol Sin ; 45(4): 738-750, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38097716

RESUMEN

Myocardial hypertrophy is a pathological thickening of the myocardium which ultimately results in heart failure. We previously reported that zonisamide, an antiepileptic drug, attenuated pressure overload-caused myocardial hypertrophy and diabetic cardiomyopathy in murine models. In addition, we have found that the inhibition of proteasome activates glycogen synthesis kinase 3 (GSK-3) thus alleviates myocardial hypertrophy, which is an important anti-hypertrophic strategy. In this study, we investigated whether zonisamide prevented pressure overload-caused myocardial hypertrophy through suppressing proteasome. Pressure overload-caused myocardial hypertrophy was induced in mice by trans-aortic constriction (TAC) surgery. Two days after the surgery, the mice were administered zonisamide (10, 20, 40 mg·kg-1·d-1, i.g.) for four weeks. We showed that zonisamide administration significantly mitigated impaired cardiac function. Furthermore, zonisamide administration significantly inhibited proteasome activity as well as the expression levels of proteasome subunit beta types (PSMB) of the 20 S proteasome (PSMB1, PSMB2 and PSMB5) and proteasome-regulated particles (RPT) of the 19 S proteasome (RPT1, RPT4) in heart tissues of TAC mice. In primary neonatal rat cardiomyocytes (NRCMs), zonisamide (0.3 µM) prevented myocardial hypertrophy triggered by angiotensin II (Ang II), and significantly inhibited proteasome activity, proteasome subunits and proteasome-regulated particles. In Ang II-treated NRCMs, we found that 18α-glycyrrhetinic acid (18α-GA, 2 mg/ml), a proteasome inducer, eliminated the protective effects of zonisamide against myocardial hypertrophy and proteasome. Moreover, zonisamide treatment activated GSK-3 through inhibiting the phosphorylated AKT (protein kinase B, PKB) and phosphorylated liver kinase B1/AMP-activated protein kinase (LKB1/AMPKα), the upstream of GSK-3. Zonisamide treatment also inhibited GSK-3's downstream signaling proteins, including extracellular signal-regulated kinase (ERK) and GATA binding protein 4 (GATA4), both being the hypertrophic factors. Collectively, this study highlights the potential of zonisamide as a new therapeutic agent for myocardial hypertrophy, as it shows potent anti-hypertrophic potential through the suppression of proteasome.


Asunto(s)
Anticonvulsivantes , Bloqueadores de los Canales de Calcio , Cardiomegalia , Glucógeno Sintasa Quinasa 3 , Complejo de la Endopetidasa Proteasomal , Zonisamida , Animales , Ratones , Ratas , Proteínas Quinasas Activadas por AMP/metabolismo , Cardiomegalia/tratamiento farmacológico , Glucógeno Sintasa Quinasa 3/farmacología , Ratones Endogámicos C57BL , Miocitos Cardíacos , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Zonisamida/farmacología , Zonisamida/uso terapéutico , Anticonvulsivantes/farmacología , Anticonvulsivantes/uso terapéutico , Bloqueadores de los Canales de Calcio/farmacología , Bloqueadores de los Canales de Calcio/uso terapéutico
10.
BMC Ophthalmol ; 24(1): 53, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38308223

RESUMEN

BACKGROUND: Late-onset capsule block syndrome (CBS) is a rare complication of cataract phacoemulsification and the implantation of a posterior chamber intraocular lens (PCIOL), which manifests six months to years after surgery. The hallmark of CBS is the formation of an opaque liquid substance between the implanted intraocular lens (IOL) and the posterior capsule. However, its pathogenesis remains unclear. CASE PRESENTATION: A 64-year-old female patient with chronic angle-closure glaucoma (axis length < 21 mm) underwent trabeculectomy surgery combined with phacoemulsification and PCIOL. After a 4-year follow-up, a decline in visual acuity occurred in her right eye due to the location of opaque fluid in the visual axis and distension of the capsular bag. The initial course of action was to release the trapped fluid. Neodymium: yttrium-aluminum-garnet (Nd: YAG) laser capsulotomy could not be employed due to her non-dilating pupil and high extension of the posterior capsule. Subsequently, anterior capsule peeling and anterior segment vitrectomy surgery were performed. The depth of the anterior chamber (ACD), the distance between the face of the retro-IOL and the posterior capsule, the best-corrected visual acuity (BCVA), and the visual quality (VQ) were measured both before and after surgery. Inflammatory cytokine levels in the opaque substances (OS) trapped between the PCIOL and the posterior capsule were assessed using a flow cytometer and compared to normal statistical data in aqueous humor. After surgery, the patient experienced a significant improvement in BCVA and VQ. The distance between the face of the retro-IOL and the posterior capsule was on the verge of disappearing. However, ACD did not differ between pre- and post-operatively. Interleukin-8 (IL-8) and basic fibroblast growth factor (BFGF) concentrations were higher in the OS than in aqueous humor, especially in the former. However, the concentration of vascular cell adhesion molecule (VCAM) in the OS was lower than in aqueous humor. CONCLUSIONS: Anterior segment vitrectomy surgery proved to be a successful treatment for late-onset CBS, presenting a challenging case. In the human lens, inflammatory cytokines originating from the opaque substances may contribute to abnormal metabolism in the sealed area, a consequence of late-onset CBS.


Asunto(s)
Extracción de Catarata , Lesiones Oculares , Cápsula del Cristalino , Enfermedades del Cristalino , Facoemulsificación , Humanos , Femenino , Persona de Mediana Edad , Citocinas , Implantación de Lentes Intraoculares/efectos adversos , Enfermedades del Cristalino/diagnóstico , Enfermedades del Cristalino/etiología , Enfermedades del Cristalino/cirugía , Cápsula del Cristalino/cirugía , Cápsula del Cristalino/patología , Extracción de Catarata/efectos adversos , Facoemulsificación/efectos adversos , Lesiones Oculares/complicaciones , Complicaciones Posoperatorias/cirugía
11.
Reprod Domest Anim ; 59(4): e14565, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38646981

RESUMEN

Mangiferin (MGN) is primarily found in the fruits, leaves, and bark of plants of the Anacardiaceae family, including mangoes. MGN exhibits various pharmacological effects, such as protection of the liver and gallbladder, anti-lipid peroxidation, and cancer prevention. This study aimed to investigate the effects of MGN supplementation during in vitro culture (IVC) on the antioxidant capacity of early porcine embryos and the underlying mechanisms involved. Porcine parthenotes in the IVC medium were exposed to different concentrations of MGN (0, 0.01, 0.1, and 1 µM). The addition of 0.1 µM MGN significantly increased the blastocyst formation rate of porcine embryos while reducing the apoptotic index and autophagy. Furthermore, the expression of antioxidation-related (SOD2, GPX1, NRF2, UCHL1), cell pluripotency (SOX2, NANOG), and mitochondria-related (TFAM, PGC1α) genes was upregulated. In contrast, the expression of apoptosis-related (CAS3, BAX) and autophagy-related (LC3B, ATG5) genes decreased after MGN supplementation. These findings suggest that MGN improves early porcine embryonic development by reducing oxidative stress-related genes.


Asunto(s)
Técnicas de Cultivo de Embriones , Desarrollo Embrionario , Estrés Oxidativo , Xantonas , Animales , Estrés Oxidativo/efectos de los fármacos , Desarrollo Embrionario/efectos de los fármacos , Xantonas/farmacología , Técnicas de Cultivo de Embriones/veterinaria , Apoptosis/efectos de los fármacos , Antioxidantes/farmacología , Autofagia/efectos de los fármacos , Porcinos , Blastocisto/efectos de los fármacos , Femenino , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Partenogénesis
12.
Reprod Domest Anim ; 59(6): e14631, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38828566

RESUMEN

This study examines the impact of Notoginsenoside R1 (NGR1), a compound from Panax notoginseng, on the maturation of porcine oocytes and their embryonic development, focusing on its effects on antioxidant levels and mitochondrial function. This study demonstrates that supplementing in vitro maturation (IVM) medium with NGR1 significantly enhances several biochemical parameters. These include elevated levels of glutathione (GSH), nuclear factor erythrocyte 2-related factor 2 (NRF2) and mRNA expression of catalase (CAT) and GPX. Concurrently, we observed a decrease in reactive oxygen species (ROS) levels and an increase in JC-1 immunofluorescence, mitochondrial distribution, peroxisome proliferator-activated receptor-γ coactivator-1α (PGC1α) and nuclear NRF2 mRNA levels. Additionally, there was an increase in ATP production and lipid droplets (LDs) immunofluorescence. These biochemical improvements correlate with enhanced embryonic outcomes, including a higher blastocyst rate, increased total cell count, enhanced proliferative capacity and elevated octamer-binding transcription factor 4 (Oct4) and superoxide dismutase 2 (Sod2) gene expression. Furthermore, NGR1 supplementation resulted in decreased apoptosis, reduced caspase 3 (Cas3) and BCL2-Associated X (Bax) mRNA levels and decreased glucose-regulated protein 78 kD (GRP78) immunofluorescence in porcine oocytes undergoing in vitro maturation. These findings suggest that NGR1 plays a crucial role in promoting porcine oocyte maturation and subsequent embryonic development by providing antioxidant levels and mitochondrial protection.


Asunto(s)
Antioxidantes , Desarrollo Embrionario , Ginsenósidos , Técnicas de Maduración In Vitro de los Oocitos , Mitocondrias , Oocitos , Animales , Antioxidantes/farmacología , Ginsenósidos/farmacología , Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Mitocondrias/efectos de los fármacos , Desarrollo Embrionario/efectos de los fármacos , Oocitos/efectos de los fármacos , Femenino , Porcinos , Especies Reactivas de Oxígeno/metabolismo , Técnicas de Cultivo de Embriones/veterinaria
13.
Geriatr Nurs ; 57: 58-65, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38537554

RESUMEN

AIM: To explore the prevalence of kinesiophobia in older patients with primary osteoporosis and analyze its influencing factors. METHODS: A cross-sectional survey was conducted among 221 older patients with primary osteoporosis in a general hospital in Kunming, China. Data were collected through a sociodemographic-clinical questionnaire, Tampa Scale for Kinesiophobia-11 (TSK-11), Global Pain Scale (GPS), Five Facets Mindfulness Questionnaire-Short Form (FFMQ-SF), and Hospital Anxiety and Depression Scale (HADS). SPSS 27.0 software was utilized for univariate and binary logistic regression analyses. RESULTS: The findings revealed that the prevalence of kinesiophobia in this study was 57.01 %. Age, history of fractures, chronic obstructive pulmonary disease (COPD), lumbar disc herniation, chronic pain, mindfulness, anxiety, and depression were identified as significant influencing factors of kinesiophobia in the binary logistic regression analyses. CONCLUSION: Healthcare professionals should be attentive to occurrence of kinesiophobia. Timely measures should be implemented to improve pain, anxiety and depression, and employ mindfulness interventions to mitigate kinesiophobia.


Asunto(s)
Osteoporosis , Trastornos Fóbicos , Humanos , Estudios Transversales , Femenino , Masculino , Anciano , Prevalencia , Osteoporosis/psicología , Encuestas y Cuestionarios , China/epidemiología , Trastornos Fóbicos/psicología , Trastornos Fóbicos/epidemiología , Depresión/psicología , Depresión/epidemiología , Ansiedad/psicología , Ansiedad/epidemiología , Persona de Mediana Edad , Anciano de 80 o más Años , Kinesiofobia
14.
J Xray Sci Technol ; 32(4): 993-1009, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38728198

RESUMEN

BACKGROUND: Accurate volumetric segmentation of primary central nervous system lymphoma (PCNSL) is essential for assessing and monitoring the tumor before radiotherapy and the treatment planning. The tedious manual segmentation leads to interindividual and intraindividual differences, while existing automatic segmentation methods cause under-segmentation of PCNSL due to the complex and multifaceted nature of the tumor. OBJECTIVE: To address the challenges of small size, diffused distribution, poor inter-layer continuity on the same axis, and tendency for over-segmentation in brain MRI PCNSL segmentation, we propose an improved attention module based on nnUNet for automated segmentation. METHODS: We collected 114 T1 MRI images of patients in the Huashan Hospital, Shanghai. Then randomly split the total of 114 cases into 5 distinct training and test sets for a 5-fold cross-validation. To efficiently and accurately delineate the PCNSL, we proposed an improved attention module based on nnU-Net with 3D convolutions, batch normalization, and residual attention (res-attention) to learn the tumor region information. Additionally, multi-scale dilated convolution kernels with different dilation rates were integrated to broaden the receptive field. We further used attentional feature fusion with 3D convolutions (AFF3D) to fuse the feature maps generated by multi-scale dilated convolution kernels to reduce under-segmentation. RESULTS: Compared to existing methods, our attention module improves the ability to distinguish diffuse and edge enhanced types of tumors; and the broadened receptive field captures tumor features of various scales and shapes more effectively, achieving a 0.9349 Dice Similarity Coefficient (DSC). CONCLUSIONS: Quantitative results demonstrate the effectiveness of the proposed method in segmenting the PCNSL. To our knowledge, this is the first study to introduce attention modules into deep learning for segmenting PCNSL based on brain magnetic resonance imaging (MRI), promoting the localization of PCNSL before radiotherapy.


Asunto(s)
Neoplasias del Sistema Nervioso Central , Linfoma , Imagen por Resonancia Magnética , Humanos , Imagen por Resonancia Magnética/métodos , Linfoma/diagnóstico por imagen , Neoplasias del Sistema Nervioso Central/diagnóstico por imagen , Femenino , Masculino , Persona de Mediana Edad , Adulto , Procesamiento de Imagen Asistido por Computador/métodos , Encéfalo/diagnóstico por imagen , Anciano
15.
Angew Chem Int Ed Engl ; : e202412073, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39266452

RESUMEN

The design and synthesis of hybrid borates by the organic ligand modification method are urgent and undeveloped areas of research. It is difficult to directly integrate organoboronic acids within inorganic borate chemistry by adopting the traditional preparation approaches. This work reports a facile synthetic method to synthesize a large family of pyrazole molecule-protected borates in a rapid and precise manner under mild conditions. A unique cyclic eight-membered B4O4-ring has been identified as the cluster core for all these hybrid borates with two different conformations (boat and crown). This strategy can be applied to a system of pyrazolyl molecules to generate such hybrid borates in two independent routes from organoboronic or inorganic boric acids. Furtherly, the mechanism of 'click reaction' between boric acid and pyrazole induced by copper ions has been proposed based on the synthetic conditions and the structure of intermediate. Due to the bimetallic Cu sites and the functional surfaces, these materials can be used as electrocatalysts for CO2 reduction reaction and efficiently enhance the selectivity of HCOOH and C2H4. Our strategy can be regarded as a typical template technique for organic molecule-protected borates.

16.
Angew Chem Int Ed Engl ; : e202411725, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39045805

RESUMEN

The strategy of in vivo self-assembly has been developed for improved enrichment and long-term retention of anticancer drug in tumor tissues. However, most self-assemblies with non-covalent bonding interactions are susceptible to complex physiological environments, leading to weak stability and loss of biological function. Here, we develop a coupling-induced assembly (CIA) strategy to generate covalently crosslinked nanofibers, which is applied for in situ constructing artificial shell on mitochondria. The oxidation-responsive peptide-porphyrin conjugate P1 is synthesized, which self-assemble into nanoparticles. Under the oxidative microenvironment of mitochondria, the coupling of thiols in P1 causes the formation of dimers, which is further ordered and stacked into crosslinked nanofibers. As a result, the artificial shell is constructed on the mitochondria efficiently through multivalent cooperative interactions due to the increased binding sites. Under ultrasound (US) irradiation, the porphyrin molecules in the shell produce a large amount of reactive oxygen species (ROS) that act on the adjacent mitochondrial membrane, exhibiting ~2-fold higher antitumor activity than nanoparticles in vitro and in vivo. Therefore, the mitochondria-targeted CIA strategy provides a novel perspective on improved sonodynamic therapy (SDT) and shows potential applications in antitumor therapies.

17.
Mol Biol Evol ; 39(2)2022 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-35084499

RESUMEN

Considerable attention has recently been focused on the potential involvement of DNA methylation in regulating gene expression in cnidarians. Much of this work has been centered on corals, in the context of changes in methylation perhaps facilitating adaptation to higher seawater temperatures and other stressful conditions. Although first proposed more than 30 years ago, the possibility that DNA methylation systems function in protecting animal genomes against the harmful effects of transposon activity has largely been ignored since that time. Here, we show that transposons are specifically targeted by the DNA methylation system in cnidarians, and that the youngest transposons (i.e., those most likely to be active) are most highly methylated. Transposons in longer and highly active genes were preferentially methylated and, as transposons aged, methylation levels declined, reducing the potentially harmful side effects of CpG methylation. In Cnidaria and a range of other invertebrates, correlation between the overall extent of methylation and transposon content was strongly supported. Present transposon burden is the dominant factor in determining overall level of genomic methylation in a range of animals that diverged in or before the early Cambrian, suggesting that genome defense represents the ancestral role of CpG methylation.


Asunto(s)
Cnidarios , Metilación de ADN , Animales , Cnidarios/genética , Islas de CpG , Genoma , Invertebrados/genética
18.
BMC Plant Biol ; 23(1): 256, 2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37189032

RESUMEN

BACKGROUND: Heat stress threatens rice yield and quality at flowering stage. In this study, average relative seed setting rate under heat stress (RHSR) and genotypes of 284 varieties were used for a genome-wide association study. RESULTS: We identified eight and six QTLs distributed on chromosomes 1, 3, 4, 5, 7 and 12 in the full population and indica, respectively. qHTT4.2 was detected in both the full population and indica as an overlapping QTL. RHSR was positively correlated with the accumulation of heat-tolerant superior alleles (SA), and indica accession contained at least two heat-tolerant SA with average RHSR greater than 43%, meeting the needs of stable production and heat-tolerant QTLs were offer yield basic for chalkiness degree, amylose content, gel consistency and gelatinization temperature. Chalkiness degree, amylose content, and gelatinization temperature under heat stress increased with accumulation of heat-tolerant SA. Gel consistency under heat stress decreased with polymerization of heat-tolerant SA. The study revealed qHTT4.2 as a stable heat-tolerant QTL that can be used for breeding that was detected in the full population and indica. And the grain quality of qHTT4.2-haplotype1 (Hap1) with chalk5, wx, and alk was better than that of qHTT4.2-Hap1 with CHALK5, WX, and ALK. Twelve putative candidate genes were identified for qHTT4.2 that enhance RHSR based on gene expression data and these genes were validated in two groups. Candidate genes LOC_Os04g52830 and LOC_Os04g52870 were induced by high temperature. CONCLUSIONS: Our findings identify strong heat-tolerant cultivars and heat-tolerant QTLs with great potential value to improve rice tolerance to heat stress, and suggest a strategy for the breeding of yield-balance-quality heat-tolerant crop varieties.


Asunto(s)
Oryza , Oryza/genética , Oryza/metabolismo , Estudio de Asociación del Genoma Completo , Alelos , Amilosa/metabolismo , Fitomejoramiento , Proteínas Tirosina Quinasas Receptoras/genética
19.
Plant Cell ; 32(2): 392-413, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31806675

RESUMEN

The spikelet is an inflorescence structure unique to grasses. The molecular mechanisms underlying spikelet development and evolution are unclear. In this study, we characterized three allelic recessive mutants in rice (Oryza sativa): nonstop glumes 1-1 (nsg1-1), nsg1-2, and nsg1-3 In these mutants, organs such as the rudimentary glume, sterile lemma, palea, lodicule, and filament were elongated and/or widened, or transformed into lemma- and/or marginal region of the palea-like organs. NSG1 encoded a member of the C2H2 zinc finger protein family and was expressed mainly in the organ primordia of the spikelet. In the nsg1-1 mutant spikelet, LHS1 DL, and MFO1 were ectopically expressed in two or more organs, including the rudimentary glume, sterile lemma, palea, lodicule, and stamen, whereas G1 was downregulated in the rudimentary glume and sterile lemma. Furthermore, the NSG1 protein was able to bind to regulatory regions of LHS1 and then recruit the corepressor TOPLESS-RELATED PROTEIN to repress expression by downregulating histone acetylation levels of the chromatin. The results suggest that NSG1 plays a pivotal role in maintaining organ identities in the spikelet by repressing the expression of LHS1, DL, and MFO1.


Asunto(s)
Dedos de Zinc CYS2-HIS2/genética , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas , Genes de Plantas/genética , Ingeniería Genética , Inflorescencia , Mutación , Fenotipo , Transcriptoma
20.
Reprod Biomed Online ; 47(2): 103211, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37246104

RESUMEN

RESEARCH QUESTION: Does the addition of an antioxidant agent, xanthoangelol (XAG), to the culture medium improve in-vitro development of porcine embryos? DESIGN: Early porcine embryos were incubated in the presence of 0.5 µmol/l XAG in in-vitro culture (IVC) media and analysed using various techniques, including immunofluorescence staining, reactive oxygen species (ROS) detection, TdT-mediated dUTP nick-end labelling (TUNEL), and reverse transcription followed by quantitative polymerase chain reaction (RT-qPCR). RESULTS: The addition of 0.5 µmol/l XAG to IVC media increased the rate of blastocyst formation, total cell number, glutathione concentrations and proliferative capacity, while reducing reactive oxygen species concentrations, apoptosis and autophagy. In addition, upon XAG treatment, the abundance of mitochondria and mitochondrial membrane potential significantly increased (both P < 0.001), and the genes related to mitochondrial biogenesis (TFAM, NRF1 and NRF2) were significantly up-regulated (all P < 0.001). XAG treatment also significantly increased the endoplasmic reticulum abundance (P < 0.001) and reduced the concentrations of endoplasmic reticulum stress (ERS) marker GRP78 (P = 0.003) and expression of the ERS-related genes EIF2α, GRP78, CHOP, ATF6, ATF4, uXBP1 and sXBP 1 (all P < 0.001). CONCLUSION: XAG promotes early embryonic development in porcine embryos in vitro by reducing oxidative stress, enhancing mitochondrial function and relieving ERS.


Asunto(s)
Chaperón BiP del Retículo Endoplásmico , Estrés del Retículo Endoplásmico , Embarazo , Animales , Femenino , Porcinos , Especies Reactivas de Oxígeno/metabolismo , Desarrollo Embrionario , Apoptosis , Mitocondrias/metabolismo , Estrés Oxidativo
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