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1.
Nature ; 612(7940): 503-511, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36477535

RESUMO

The neocortex consists of a vast number of diverse neurons that form distinct layers and intricate circuits at the single-cell resolution to support complex brain functions1. Diverse cell-surface molecules are thought to be key for defining neuronal identity, and they mediate interneuronal interactions for structural and functional organization2-6. However, the precise mechanisms that control the fine neuronal organization of the neocortex remain largely unclear. Here, by integrating in-depth single-cell RNA-sequencing analysis, progenitor lineage labelling and mosaic functional analysis, we report that the diverse yet patterned expression of clustered protocadherins (cPCDHs)-the largest subgroup of the cadherin superfamily of cell-adhesion molecules7-regulates the precise spatial arrangement and synaptic connectivity of excitatory neurons in the mouse neocortex. The expression of cPcdh genes in individual neocortical excitatory neurons is diverse yet exhibits distinct composition patterns linked to their developmental origin and spatial positioning. A reduction in functional cPCDH expression causes a lateral clustering of clonally related excitatory neurons originating from the same neural progenitor and a significant increase in synaptic connectivity. By contrast, overexpression of a single cPCDH isoform leads to a lateral dispersion of clonally related excitatory neurons and a considerable decrease in synaptic connectivity. These results suggest that patterned cPCDH expression biases fine spatial and functional organization of individual neocortical excitatory neurons in the mammalian brain.


Assuntos
Regulação da Expressão Gênica , Neocórtex , Protocaderinas , Animais , Camundongos , Interneurônios/metabolismo , Neocórtex/anatomia & histologia , Neocórtex/citologia , Neocórtex/metabolismo , Neurônios/metabolismo , Protocaderinas/genética , Protocaderinas/metabolismo , Sinapses/metabolismo , Transmissão Sináptica
2.
J Bone Miner Metab ; 42(3): 372-381, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38795128

RESUMO

INTRODUCTION: The effect of nutritional status on osteosarcopenia (OS) and major osteoporotic fracture (MOF) among the elderly is still unclear. So we aimed to compare the efficacy of the Mini-Nutrition Assessment-Short Form (MNA-sf), the Geriatric Nutritional Risk Index (GNRI) and Controlling Nutritional Status (CONUT) for predicting OS and MOF among the elderly. MATERIALS AND METHODS: A total of 409 participants were enrolled in this prospective study. Blood biochemical indexes, nutritional status, and bone- and muscle-related examinations were assessed at initial visit to the outpatient. Participants were divided into 4 groups: (1) control; (2) osteopenia/osteoporosis; (3) sarcopenia; (4) osteosarcopenia, and then followed for 5 years, recording the occurrence time of MOF. RESULTS: The frequency values of osteopenia/osteoporosis, sarcopenia, and OS, at baseline, were respectively 13.4, 16.1, and 12% among the study samples. Correlation analysis showed that nutritional status scores were associated with body mass index, handgrip strength, albumin, bone mineral density, and physical functions. According to multivariate models, poor nutritional status was significantly associated with a higher risk of OS and MOF (P < 0.05). Survival analysis showed that the MOF rate in malnutrition group was significantly higher than normal nutrition group (P < 0.05). The receiver operator characteristic curve shows that the value of MNA-sf to diagnose OS and MOF is greater (P < 0.05). CONCLUSION: The poor nutritional status was associated with a higher risk of both OS and MOF. MNA-sf showed a superior diagnostic power for OS and MOF among the elderly. Early nutrition assessments and interventions may be key strategies to prevent OS and fractures.


Assuntos
Estado Nutricional , Fraturas por Osteoporose , Sarcopenia , Humanos , Sarcopenia/sangue , Sarcopenia/diagnóstico , Sarcopenia/epidemiologia , Idoso , Feminino , Masculino , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/sangue , Incidência , Estudos Prospectivos , Avaliação Nutricional , Idoso de 80 Anos ou mais , Doenças Ósseas Metabólicas/epidemiologia , Doenças Ósseas Metabólicas/sangue , Densidade Óssea , Osteoporose/epidemiologia , Osteoporose/sangue , Osteoporose/diagnóstico , Pessoa de Meia-Idade
3.
Inorg Chem ; 63(20): 9307-9314, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38718357

RESUMO

Single atom site catalysts (SACs) with atomically dispersed active sites can be expected to be potential ideal catalysts for accurately modulating the persulfate activation pathway during the water remediation process because of their well-defined structure and the maximum metallic atom utilization. In this paper, a series of Cu SACs with different coordination environments were synthesized to elaborately regulate the peroxymonosulfate activation pathway in AOPs to clarify active species generation and transformation in water remediation. The degradation rate constants (kobs) of Cu-N2, Cu-N3, and Cu-N4 were 0.028, 0.021, and 0.015 min-1, respectively. Cu-N2 SACs exhibited a noticeable enhanced performance for bisphenol A (BPA) removal from water compared to that of the Cu-Nx SACs (x = 3, 4), accompanied by peroxymonosulfate (PMS) activation pathway variation. As shown by experimental and theoretical results, the PMS activation pathway was transformed from ROS to electron transfer with nitrogen coordination numbers decreasing from 4 to 2, which can be ascribed to the uneven charge distribution of Cu sites as well as upshifts in the d-band center, and thereby optimized electron transfer for PMS activation. Furthermore, the increasing nitrogen vacancies of single Cu site catalysts can also result in more unoccupied 3d orbitals of Cu atoms in SACs, thereby improving the intermediates' (PMS and BPA) adsorption-desorption process and BPA removal performance. These findings provided a beneficial approach for the coordination number regulation of SACs in water remediation.

4.
J Nanobiotechnology ; 22(1): 94, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38449005

RESUMO

BACKGROUND: Impaired osteo-/angiogenesis, excessive inflammation, and imbalance of the osteoimmune homeostasis are involved in the pathogenesis of the alveolar bone defect caused by periodontitis. Unfortunately, there is still a lack of ideal therapeutic strategies for periodontitis that can regenerate the alveolar bone while remodeling the osteoimmune microenvironment. Quercetin, as a monomeric flavonoid, has multiple pharmacological activities, such as pro-regenerative, anti-inflammatory, and immunomodulatory effects. Despite its vast spectrum of pharmacological activities, quercetin's clinical application is limited due to its poor water solubility and low bioavailability. RESULTS: In this study, we fabricated a quercetin-loaded mesoporous bioactive glass (Quercetin/MBG) nano-delivery system with the function of continuously releasing quercetin, which could better promote the bone regeneration and regulate the immune microenvironment in the alveolar bone defect with periodontitis compared to pure MBG treatment. In particular, this nano-delivery system effectively decreased injection frequency of quercetin while yielding favorable therapeutic results. In view of the above excellent therapeutic effects achieved by the sustained release of quercetin, we further investigated its therapeutic mechanisms. Our findings indicated that under the periodontitis microenvironment, the intervention of quercetin could restore the osteo-/angiogenic capacity of periodontal ligament stem cells (PDLSCs), induce immune regulation of macrophages and exert an osteoimmunomodulatory effect. Furthermore, we also found that the above osteoimmunomodulatory effects of quercetin via macrophages could be partially blocked by the overexpression of a key microRNA--miR-21a-5p, which worked through inhibiting the expression of PDCD4 and activating the NF-κB signaling pathway. CONCLUSION: In summary, our study shows that quercetin-loaded mesoporous nano-delivery system has the potential to be a therapeutic approach for reconstructing alveolar bone defects in periodontitis. Furthermore, it also offers a new perspective for treating alveolar bone defects in periodontitis by inhibiting the expression of miR-21a-5p in macrophages and thereby creating a favorable osteoimmune microenvironment.


Assuntos
NF-kappa B , Periodontite , Humanos , Quercetina/farmacologia , Periodontite/tratamento farmacológico , Flavonoides , Inflamação , Proteínas de Ligação a RNA , Proteínas Reguladoras de Apoptose
5.
Int Wound J ; 21(4): e14867, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38597295

RESUMO

Non-healing wounds are one of the chronic complications of diabetes and have remained a worldwide challenge as one of the major health problems. Hyperbaric oxygen (HBO) therapy is proven to be very successful for diabetic wound treatment, for which the molecular basis is not understood. Adipocytes regulate multiple aspects of repair and may be therapeutic for inflammatory diseases and defective wound healing associated with aging and diabetes. Endothelial cell-derived extracellular vesicles could promote wound healing in diabetes. To study the mechanism by which HBO promotes wound healing in diabetes, we investigated the effect of HBO on fat cells in diabetic mice. A diabetic wound mouse model was established and treated with HBO. Haematoxylin and eosin (H&E) staining and immunofluorescence were used for the analysis of wound healing. To further explore the mechanism, we performed whole-genome sequencing on extracellular vesicles (EVs). Furthermore, we conducted in vitro experiments. Specifically, exosomes were collected from human umbilical vein endothelial cell (HUVEC) cells after HBO treatment, and then these exosomes were co-incubated with adipose tissue. The wound healing rate in diabetic mice treated with HBO was significantly higher. HBO therapy promotes the proliferation of adipose precursor cells. HUVEC-derived exosomes treated with HBO significantly promoted fat cell browning. These data clarify that HBO therapy may promote vascular endothelial cell proliferation and migration, and promote browning of fat cells through vascular endothelial cells derived exosomes, thereby promoting diabetic wound healing. This provides new ideas for the application of HBO therapy in the treatment of diabetic trauma.


Assuntos
Diabetes Mellitus Experimental , Oxigenoterapia Hiperbárica , Humanos , Animais , Camundongos , Cicatrização/fisiologia , Diabetes Mellitus Experimental/terapia , Células Endoteliais da Veia Umbilical Humana , Tecido Adiposo Branco
6.
J Cell Mol Med ; 27(17): 2482-2494, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37409682

RESUMO

Around the world, tuberculosis (TB) remains one of the most common causes of morbidity and mortality. The molecular mechanism of Mycobacterium tuberculosis (Mtb) infection is still unclear. Extracellular vesicles (EVs) play a key role in the onset and progression of many disease states and can serve as effective biomarkers or therapeutic targets for the identification and treatment of TB patients. We analysed the expression profile to better clarify the EVs characteristics of TB and explored potential diagnostic markers to distinguish TB from healthy control (HC). Twenty EVs-related differentially expressed genes (DEGs) were identified, and 17 EVs-related DEGs were up-regulated and three DEGs were down-regulated in TB samples, which were related to immune cells. Using machine learning, a nine EVs-related gene signature was identified and two EVs-related subclusters were defined. The single-cell RNA sequence (scRNA-seq) analysis further confirmed that these hub genes might play important roles in TB pathogenesis. The nine EVs-related hub genes had excellent diagnostic values and accurately estimated TB progression. TB's high-risk group had significantly enriched immune-related pathways, and there were substantial variations in immunity across different groups. Furthermore, five potential drugs were predicted for TB using CMap database. Based on the EVs-related gene signature, the TB risk model was established through a comprehensive analysis of different EV patterns, which can accurately predict TB. These genes could be used as novel biomarkers to distinguish TB from HC. These findings lay the foundation for further research and design of new therapeutic interventions aimed at treating this deadly infectious disease.


Assuntos
Vesículas Extracelulares , Mycobacterium tuberculosis , Tuberculose , Humanos , Tuberculose/diagnóstico , Tuberculose/genética , Mycobacterium tuberculosis/genética , Vesículas Extracelulares/genética , Vesículas Extracelulares/metabolismo , Biomarcadores/metabolismo
7.
J Am Chem Soc ; 145(16): 9233-9241, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37043290

RESUMO

A new strategy focusing on the last-stage asymmetric assembly of the ring D, which inherently possesses the densest part of stereogenic centers and functional groups in the A/B/C/D ring system of (-)-cephalotaxine, has been developed, in which a novel Rh-catalyzed asymmetric (2 + 3) annulation of tertiary enamides with enoldiazoacetates is designed and explored for enantioselective construction of the crucial cyclopentane ring D bearing a unique spirocyclic aza-quaternary stereocenter. Based on the expeditious access of chiral functionalized building block with the tetracyclic A/B/C/D ring system, a concise enantioselective total synthesis of (-)-cephalotaxine starting from readily available homopiperonyl alcohol has been achieved in nine steps with only two column chromatography purifications. Following the tactical introduction of the Meinwald rearrangement, enantioselective divergent syntheses of (-)-cephalotine B with an additional C3-O-C11 oxo-bridged bond (14 steps), (-)-fortuneicyclidin B with an unprecedented C3-C10 bond (14 steps), and its 2-epimer (-)-fortuneicyclidin A (16 steps) have been also accomplished for the first time.

8.
Clin Chem Lab Med ; 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38000044

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) which caused coronavirus disease-2019 (COVID-19) is spreading worldwide and posing enormous losses to human health and socio-economic. Due to the limitations of medical and health conditions, it is still a huge challenge to develop appropriate discharge standards for patients with COVID-19 and to use medical resources in a timely and effective manner. Similar to other coronaviruses, SARS-CoV-2 has a very complex discontinuous transcription process to generate subgenomic RNA (sgRNA). Some studies support that sgRNA of SARS-CoV-2 can only exist when the virus is active and is an indicator of virus replication. The results of sgRNA detection in patients can be used to evaluate the condition of hospitalized patients, which is expected to save medical resources, especially personal protective equipment. There have been numerous investigations using different methods, especially molecular methods to detect sgRNA. Here, we introduce the process of SARS-CoV-2 sgRNA formation and the commonly used molecular diagnostic methods to bring a new idea for clinical detection in the future.

9.
BMC Cardiovasc Disord ; 23(1): 382, 2023 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-37525092

RESUMO

BACKGROUND: The postoperative outcomes of transcatheter aortic valve replacement (TAVR) with the new generation of self-expanding valves (SEV) and balloon-expandable valves (BEV) remain uncertain. METHODS: We conducted a meta-analysis based on randomized controlled trials (RCTs) and propensity score-matched (PSM) studies to evaluate the performance of the new generation TAVR devices, with a focus on Edwards SAPIEN 3/Ultra BEV, Medtronic Evolut R/PRO SEV, and Boston ACURATE neo SEV. Our primary endpoints were mortality and complications at both 30 days and one year post-operation. RESULTS: A total of 4 RCTs and 14 PSM studies were included. Our findings showed no significant difference between SEV and BEV regarding 30-day and 1-year mortality rates. ACURATE SEV required less permanent pacemaker implantation (PPI) at 30-day as compared to SAPIEN BEV, while Evolut SEV required a higher rate of PPI than SAPIEN BEV. The incidence of stroke, major or life-threatening bleeding (MLTB), major vascular complications (MVC), coronary artery obstruction (CAO) and acute kidney injury (AKI) did not differ significantly between the two groups. SEV had a larger effective orifice area (EOA) and lower mean transvalvular gradients (MPG) compared to BEV. However, there was an increased risk of paravalvular leakage (PVL) associated with SEV. CONCLUSIONS: In terms of 30-day mortality, stroke, bleeding, MVC, AKI, CAO, and one-year mortality, there was comparability between the two valve types following TAVR. SEV was associated with better hemodynamic outcomes, except for a higher incidence of PVL. Compared to SAPIEN BEV, ACURATE SEV had a lower risk of PPI at 30 days, while Evolut SEV was associated with a higher risk of PPI. These findings underscore the importance of personalized valve selection.


Assuntos
Estenose da Valva Aórtica , Próteses Valvulares Cardíacas , Acidente Vascular Cerebral , Substituição da Valva Aórtica Transcateter , Humanos , Substituição da Valva Aórtica Transcateter/efeitos adversos , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Estenose da Valva Aórtica/epidemiologia , Próteses Valvulares Cardíacas/efeitos adversos , Acidente Vascular Cerebral/epidemiologia , Incidência , Resultado do Tratamento , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Desenho de Prótese
10.
J Immunol ; 204(3): 682-693, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31871023

RESUMO

Eosinophilia is a hallmark of allergic airway inflammation (AAI). Identifying key molecules and specific signaling pathways that regulate eosinophilic inflammation is critical for development of novel therapeutics. Tropomycin receptor kinase A (TrkA) is the high-affinity receptor for nerve growth factor. AAI is associated with increased expression of TrkA by eosinophils; however, the functional role of TrkA in regulating eosinophil recruitment and contributing to AAI is poorly understood. This study identifies, to our knowledge, a novel mechanism of eotaxin-mediated activation of TrkA and its role in regulating eosinophil recruitment by using a chemical-genetic approach to specifically inhibit TrkA kinase activity with 1-NM-PP1 in TrkAF592A-knock-in (TrkA-KI) eosinophils. Blockade of TrkA by 1-NM-PP1 enhanced eosinophil spreading on VCAM-1 but inhibited eotaxin-1 (CCL11)-mediated eosinophil migration, calcium flux, cell polarization, and ERK1/2 activation, suggesting that TrkA is an important player in the signaling pathway activated by eotaxin-1 during eosinophil migration. Further, blockade of matrix metalloprotease with BB-94 inhibited eotaxin-1-induced TrkA activation and eosinophil migration, additively with 1-NM-PP1, indicating a role for matrix metalloproteases in TrkA activation. TrkA inhibition in Alternaria alternata-challenged TrkA-KI mice markedly inhibited eosinophilia and attenuated various features of AAI. These findings are indicative of a distinctive eotaxin-mediated TrkA-dependent signaling pathway, which, in addition to other TrkA-activating mediators, contributes to eosinophil recruitment during AAI and suggests that targeting the TrkA signaling pathway to inhibit eosinophil recruitment may serve as a therapeutic strategy for management of eosinophilic inflammation in allergic airway disease, including asthma.


Assuntos
Alternaria/fisiologia , Alternariose/imunologia , Asma/imunologia , Eosinófilos/imunologia , Hipersensibilidade/imunologia , Receptor trkA/metabolismo , Hipersensibilidade Respiratória/imunologia , Animais , Movimento Celular , Células Cultivadas , Quimiocina CCL11/metabolismo , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Mutantes , Mutação/genética , Receptor trkA/genética , Transdução de Sinais
11.
Acta Neurol Scand ; 146(5): 635-642, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36062837

RESUMO

BACKGROUND: Robust collateral circulation is strongly associated with good outcomes in acute ischemic stroke (AIS). AIMS: To determine whether collateral circulation detected by arterial spin labeling (ASL) magnetic resonance imaging could predict good clinical outcome in AIS patients with 90 days follow-up. MATERIALS AND METHODS: Total 58 AIS patients with anterior circulation stroke were recruited. Collateral circulation was defined as arterial transit artifact in ASL images. Modified Rankin Scale (mRS), the Barthel Index, and National Institutes of Health Stroke Scale (NIHSS) were employed to evaluate neurological function for the baseline and 90 days follow-up. The percent changes of these scores were also calculated, respectively. Finally, a support vector classifier model of machine learning and receiver operating characteristic curve were employed to estimate the power of ASL collaterals (ASLcs) predicting the clinical outcome. RESULTS: Patients with ASLcs represented higher rate of good outcome (83.30% vs. 31.25%, p < .001) and lower follow-up mRS scores (p < .001), when compared to patients without ASLcs. There were significant differences for percent changes of mRS scores and NIHSS scores between these two groups. Further, the presence of ASLcs could predict good clinical outcome (OR, 1.54; 95% CI, 1.10-2.16), even after controlling for baseline NIHSS scores. The SVC model incorporating baseline NIHSS scores and ASLcs had significant predictive effect (accuracy, 79.3%; AUC, 0.806) on clinical prognosis for AIS patients. DISCUSSION: We targeted on the non-invasive assessment of collateral circulation using ASL technique and found that patients with ASLcs were more likely to have a good clinical outcome after AIS. This finding is of guiding significance for treatment selection and prognostic prediction. CONCLUSIONS: Early ASLcs assessment provides a good powerful tool to predict clinical outcome for AIS patients with 90 days follow-up.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Isquemia Encefálica/complicações , Circulação Cerebrovascular , Circulação Colateral , Humanos , AVC Isquêmico/diagnóstico por imagem , Estudos Retrospectivos , Marcadores de Spin , Acidente Vascular Cerebral/complicações , Resultado do Tratamento
12.
Phytother Res ; 36(11): 4167-4182, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35778992

RESUMO

Hepatocytes has been confirmed to undergo EMT and can be converted into myofibroblasts during hepatic fibrogenesis. However, the mechanism of hepatocyte EMT regulation in hepatic fibrosis, particularly through HSP27 (human homologue of rodent HSP25), remains unclear. Mangiferin (MAN), a compound extracted from Mangifera indica L, has been reported to attenuate liver injury. This study aimed to investigate the mechanisms underlying HSP27 inhibition and the anti-fibrotic effect of MAN in liver fibrosis. Our results revealed that the expression of HSP27 was remarkably increased in the liver tissues of patients with liver cirrhosis and CCl4 -induced fibrotic rats. However, HSP27 shRNA treatment significantly alleviated fibrosis. Furthermore, MAN was found to inhibit CCl4 - and TGF-ß1-induced liver fibrosis and reduced hepatocyte EMT. More importantly, MAN decreased HSP27 expression to suppress the JAK2/STAT3 pathway, and subsequently blocked TGF-ß1/Smad signaling, which were consistent with its protection against CCl4 -induced EMT and liver fibrosis. Together, these results suggest that HSP27 may play a crucial role in hepatocyte EMT and liver fibrosis by activating JAK2/STAT3 signaling and TGF-ß1/Smad pathway. The suppression of HSP27 expression by MAN may be a novel strategy for attenuating the hepatocyte EMT in liver fibrosis.


Assuntos
Transição Epitelial-Mesenquimal , Fator de Crescimento Transformador beta1 , Animais , Humanos , Ratos , Fibrose , Hepatócitos , Proteínas de Choque Térmico HSP27/metabolismo , Janus Quinase 2 , Cirrose Hepática/tratamento farmacológico , Fator de Transcrição STAT3/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Proteínas Smad/metabolismo
13.
Int J Mol Sci ; 23(7)2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35409087

RESUMO

Populus euphratica is mainly distributed in desert environments with dry and hot climate in summer and cold in winter. Compared with other poplars, P. euphratica is more resistant to salt stress. It is critical to investigate the transcriptome and molecular basis of salt tolerance in order to uncover stress-related genes. In this study, salt-tolerant treatment of P. euphratica resulted in an increase in osmo-regulatory substances and recovery of antioxidant enzymes. To improve the mining efficiency of candidate genes, the analysis combining both the transcriptome WGCNA and the former GWAS results was selected, and a range of key regulatory factors with salt resistance were found. The PeERF1 gene was highly connected in the turquoise modules with significant differences in salt stress traits, and the expression levels were significantly different in each treatment. For further functional verification of PeERF1, we obtained stable overexpression and dominant suppression transgenic lines by transforming into Populus alba × Populusglandulosa. The growth and physiological characteristics of the PeERF1 overexpressed plants were better than that of the wild type under salt stress. Transcriptome analysis of leaves of transgenic lines and WT revealed that highly enriched GO terms in DEGs were associated with stress responses, including abiotic stimuli responses, chemical responses, and oxidative stress responses. The result is helpful for in-depth analysis of the salt tolerance mechanism of poplar. This work provides important genes for poplar breeding with salt tolerance.


Assuntos
Populus , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Melhoramento Vegetal , Plantas Geneticamente Modificadas/genética , Populus/metabolismo , Tolerância ao Sal/genética , Estresse Fisiológico/genética
14.
Int J Mol Sci ; 23(4)2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35216331

RESUMO

A highly efficient Agrobacterium-mediated transformation method is needed for the molecular study of model tree species such as hybrid poplar 84K (Populus alba × P. glandulosa cv. '84K'). In this study, we report a callus-based transformation method that exhibits high efficiency and reproducibility. The optimized callus induction medium (CIM1) induced the development of calli from leaves with high efficiency, and multiple shoots were induced from calli growing on the optimized shoot induction medium (SIM1). Factors affecting the transformation frequency of calli were optimized as follows: Agrobacterium concentration sets at an OD600 of 0.6, Agrobacterium infective suspension with an acetosyringone (AS) concentration of 100 µM, infection time of 15 min, cocultivation duration of 2 days and precultivation duration of 6 days. Using this method, transgenic plants are obtained within approximately 2 months with a transformation frequency greater than 50%. Polymerase chain reaction (PCR), reverse transcription-PCR (RT-PCR) and ß-galactosidase (GUS) histochemical staining analyses confirmed the successful generation of stable transformants. Additionally, the calli from leaves were subcultured and used to obtain new explants; the high transformation efficiency was still maintained in subcultured calli after 6 cycles. This method provides a reference for developing effective transformation protocols for other poplar species.


Assuntos
Acetofenonas/metabolismo , Populus/genética , Transformação Genética/genética , Agrobacterium tumefaciens/genética , Vetores Genéticos/genética , Folhas de Planta/genética , Plantas Geneticamente Modificadas/genética , Reprodutibilidade dos Testes
15.
Opt Lett ; 46(15): 3633-3636, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34329243

RESUMO

In this paper, we provide an experimental proof-of-concept of this dynamic three-dimensional (3D) current manipulation through a 3D-printed reconfigurable meta-radiator with periodically slotted current elements. By utilizing the working frequency and the mechanical configuration comprehensively, the radiation pattern can be switched among 12 states. Inspired by maximum likelihood method in digital communications, a robustness-analysis method is proposed to evaluate the potential error ratio between ideal cases and practice. Our work provides a previously unidentified model for next-generation information distribution and terahertz-infrared wireless communications.

16.
Endocr J ; 68(9): 1101-1107, 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-33896872

RESUMO

The present study was designed to explore whether serum stromal cell-derived factor-1 (SDF-1) levels were associated with diabetic kidney disease (DKD). Serum SDF-1 levels were measured by sandwich ELISA. Patients with an estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2 or a urinary albumin-to-creatinine ratio (UACR) ≥30 mg/g for 3 months were identified as having DKD. Among the recruited type 2 diabetic patients, 18.71% (n = 32) were found to have DKD, and the serum SDF-1 levels of these patients were higher than those of patients without DKD (p < 0.05). Serum SDF-1 levels were positively correlated with cystatin C levels, the UACR and DKD incidence (r = 0.330, 0.183 and 0.186, respectively, p < 0.05) and inversely related to eGFR (r = -0.368, p < 0.001). After adjusting for other clinical covariates by multivariate logistic regression analyses, serum SDF-1 levels were found to be an independent contributor to DKD, and the odds ratio (95% confidence interval) was 1.438 (1.041-1.986). Furthermore, receiver operating characteristic analysis revealed that the optimal SDF-1 cutoff value for indicating DKD was 5.609 ng/mL (its corresponding sensitivity was 82.00%, and specificity was 46.90%). Our results demonstrated that serum SDF-1 levels were closely associated with DKD and could be considered a potent indicator for DKD in patients with T2D.


Assuntos
Quimiocina CXCL12/sangue , Diabetes Mellitus Tipo 2/complicações , Nefropatias Diabéticas/sangue , Adulto , Idoso , Albuminúria , Creatinina/urina , Estudos Transversais , Cistatina C/sangue , Diabetes Mellitus Tipo 2/sangue , Feminino , Hemoglobinas Glicadas/análise , Humanos , Masculino , Pessoa de Meia-Idade
17.
Chem Biodivers ; 18(2): e2000856, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33295037

RESUMO

Dioscorea polystachya, named Chinese yam, is widely cultivated as a functional food and natural medicine in China. There is currently little information about the chemical characteristics of Dioscorea polystachya in different organs (tuber cortex and tuber flesh) and at various ages. In this study, an ultra-high-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UPLC-QTOF/MS) was used to profile chemical compounds in Dioscorea polystachya. As a result, thirty-eight compounds were detected in yam tuber cortex and tuber flesh. More compounds were detected in yam tuber cortex than in tuber flesh. Compounds such as dehydroepiandrosterone, allantoin and flavonoids were selected as biomarker candidates. Dehydroepiandrosterone was found more abundant in tuber flesh, while allantoin and flavonoids showed higher levels in tuber cortex. Furthermore, the levels of dioscin, malvalic acid and sucrose differed significantly among age groups and were highest in the tubers at 2 years. While the levels of allantoin, adenosine and glutamine increased with the growing years and were highest at 4 years. Thus, 2-year old Dioscorea polystachya tubers could be harvested to prepare dioscin, malvalic acid and sucrose supplements. The 4-year-old Dioscorea polystachya tubers would be the best choice for obtaining a large amount of allantoin and adenosine in industrial production.


Assuntos
Dioscorea/química , Tubérculos/química , Alantoína/análise , Cromatografia Líquida de Alta Pressão/métodos , Desidroepiandrosterona/análise , Dioscorea/crescimento & desenvolvimento , Flavonoides/análise , Espectrometria de Massas/métodos , Tubérculos/crescimento & desenvolvimento
18.
J Integr Plant Biol ; 63(7): 1324-1340, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33605510

RESUMO

Mitogen-activated protein kinases (MPKs) play essential roles in guard cell signaling, but whether MPK cascades participate in guard cell ethylene signaling and interact with hydrogen peroxide (H2 O2 ), nitric oxide (NO), and ethylene-signaling components remain unclear. Here, we report that ethylene activated MPK3 and MPK6 in the leaves of wild-type Arabidopsis thaliana as well as ethylene insensitive2 (ein2), ein3, nitrate reductase1 (nia1), and nia2 mutants, but this effect was impaired in ethylene response1 (etr1), nicotinamide adenine dinucleotide phosphate oxidase AtrbohF, mpk kinase1 (mkk1), and mkk3 mutants. By contrast, the constitutive triple response1 (ctr1) mutant had constitutively active MPK3 and MPK6. Yeast two-hybrid, bimolecular fluorescence complementation, and pull-down assays indicated that MPK3 and MPK6 physically interacted with MKK1, MKK3, and the C-terminal region of EIN2 (EIN2 CEND). mkk1, mkk3, mpk3, and mpk6 mutants had typical levels of ethylene-induced H2 O2 generation but impaired ethylene-induced EIN2 CEND cleavage and nuclear translocation, EIN3 protein accumulation, NO production in guard cells, and stomatal closure. These results show that the MKK1/3-MPK3/6 cascade mediates ethylene-induced stomatal closure by functioning downstream of ETR1, CTR1, and H2 O2 to interact with EIN2, thereby promoting EIN3 accumulation and EIN3-dependent NO production in guard cells.


Assuntos
Proteínas de Arabidopsis/metabolismo , Proteínas de Ligação a DNA/metabolismo , Etilenos/farmacologia , MAP Quinase Quinase 1/metabolismo , MAP Quinase Quinase 3/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Estômatos de Plantas/efeitos dos fármacos , Estômatos de Plantas/metabolismo , Receptores de Superfície Celular/metabolismo , Fatores de Transcrição/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Ligação a DNA/genética , MAP Quinase Quinase 1/genética , MAP Quinase Quinase 3/genética , Proteínas Quinases Ativadas por Mitógeno/genética , Receptores de Superfície Celular/genética , Fatores de Transcrição/genética
19.
BMC Genomics ; 21(1): 305, 2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-32299363

RESUMO

BACKGROUND: In citrus, genetic improvement via biotechnology is hindered by the obstacle of in vitro regeneration via somatic embryogenesis (SE). Although a few B3 transcription factors are reported to regulate embryogenesis, little is known about the B3 superfamily in citrus, and which members might be involved in SE. RESULTS: Genome-wide sequence analysis identified 72 (CsB3) and 69 (CgB3) putative B3 superfamily members in the genomes of sweet orange (Citrus sinensis, polyembryonic) and pummelo (C. grandis, monoembryonic), respectively. Genome duplication analysis indicated that segmental and tandem duplication events contributed to the expansion of the B3 superfamily in citrus, and that the B3 superfamily evolved under the effect of purifying selection. Phylogenetic relationships were well supported by conserved gene structure and motifs outside the B3 domain, which allowed possible functions to be inferred by comparison with homologous genes from Arabidopsis. Expression analysis identified 23 B3 superfamily members that were expressed during SE in citrus and 17 that may play functional roles at late SE stages. Eight B3 genes were identified that were specific to the genome of polyembryonic sweet orange compared to monoembryonic pummelo. Of these eight B3 genes, CsARF19 was found to be specifically expressed at higher levels in embryogenic callus (EC), implying its possible involvement in EC initiation. CONCLUSIONS: This study provides a genome-wide analysis of the citrus B3 superfamily, including its genome organization, evolutionary features and expression profiles, and identifies specific family members that may be associated with SE.


Assuntos
Citrus/embriologia , Citrus/genética , Família Multigênica , Proteínas de Plantas/genética , Técnicas de Embriogênese Somática de Plantas , Fatores de Transcrição/genética , Arabidopsis/genética , Citrus sinensis/embriologia , Citrus sinensis/genética , Duplicação Gênica , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Estudo de Associação Genômica Ampla , Filogenia , Proteínas de Plantas/classificação , Sintenia , Fatores de Transcrição/classificação
20.
Exp Lung Res ; 46(7): 243-257, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32578458

RESUMO

Aim/Purpose: Exposure to various allergens has been shown to increase expression of ORMDL3 in the lung in models of allergic asthma. Studies using genetically modified (transgenic or knock out) mice have revealed some of the functions of ORMDL3 in asthma pathogenesis, although amid debate. The goal of this study was to use targeted post-transcriptional downregulation of ORMDL3 in allergen-challenged wild-type (WT) mice by RNA interference to further elucidate the functional role of ORMDL3 in asthma pathogenesis and evaluate a potential therapeutic option.Methods: Allergen (ovalbumin [OVA])-challenged WT mice were administered intranasally (i.n) with a single dose of five short hairpin RNA (shRNA) constructs with different target sequence for murine ORMDL3 cloned in a lentiviral vector or with the empty vector (control). Mice were evaluated for allergen-induced airway hyperresponsiveness (AHR) and various features of airway inflammation after 72 hours.Results: I.n administration of a single dose of ORMDL3 shRNAs to OVA-challenged mice resulted in reduction of ORMDL3 gene expression in the lungs associated with a significant reduction in AHR to inhaled methacholine and in the number of inflammatory cells recruited in the airways, specifically eosinophils, as well as in airway mucus secretion compared to OVA-challenged mice that received the empty vector. Administration of ORMDL3 shRNAs also significantly inhibited levels of IL-13, eotaxin-2 and sphingosine in the lungs. Additionally, ORMDL3 shRNAs significantly inhibited the allergen-mediated increase in monohexyl ceramides C22:0 and C24:0.Conclusions: Post-transcriptional down regulation of ORMDL3 in allergic lungs using i.n-delivered ORMDL3 shRNA (akin to inhaled therapy) attenuates development of key features of airway allergic disease, confirming the involvement of ORMDL3 in allergic asthma pathogenesis and serving as a model for a potential therapeutic strategy.


Assuntos
Alérgenos/metabolismo , Inflamação/metabolismo , Pulmão/metabolismo , Proteínas de Membrana/metabolismo , RNA Interferente Pequeno/metabolismo , Hipersensibilidade Respiratória/metabolismo , Animais , Asma/tratamento farmacológico , Asma/metabolismo , Hiper-Reatividade Brônquica/tratamento farmacológico , Hiper-Reatividade Brônquica/metabolismo , Líquido da Lavagem Broncoalveolar/química , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Inflamação/tratamento farmacológico , Pulmão/efeitos dos fármacos , Masculino , Cloreto de Metacolina/farmacologia , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Eosinofilia Pulmonar/tratamento farmacológico , Eosinofilia Pulmonar/metabolismo , Interferência de RNA/efeitos dos fármacos , Hipersensibilidade Respiratória/tratamento farmacológico
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