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1.
Plant Physiol ; 190(3): 1640-1657, 2022 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-36000923

RESUMO

Cuticular waxes cover the aerial surfaces of land plants and protect them from various environmental stresses. Alkanes are major wax components and contribute to plant drought tolerance, but the biosynthesis and regulation of alkanes remain largely unknown in wheat (Triticum aestivum L.). Here, we identified and functionally characterized a key alkane biosynthesis gene ECERIFERUM1-6A (TaCER1-6A) from wheat. The clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein 9 (Cas9)-mediated knockout mutation in TaCER1-6A greatly reduced the contents of C27, C29, C31, and C33 alkanes in wheat leaves, while TaCER1-6A overexpression significantly increased the contents of these alkanes in wheat leaves, suggesting that TaCER1-6A is specifically involved in the biosynthesis of C27, C29, C31, and C33 alkanes on wheat leaf surfaces. TaCER1-6A knockout lines exhibited increased cuticle permeability and reduced drought tolerance, whereas TaCER1-6A overexpression lines displayed reduced cuticle permeability and enhanced drought tolerance. TaCER1-6A was highly expressed in flag leaf blades and seedling leaf blades and could respond to abiotic stresses and abscisic acid. TaCER1-6A was located in the endoplasmic reticulum, which is the subcellular compartment responsible for wax biosynthesis. A total of three haplotypes (HapI/II/III) of TaCER1-6A were identified in 43 wheat accessions, and HapI was the dominant haplotype (95%) in these wheat varieties. Additionally, we identified two R2R3-MYB transcription factors TaMYB96-2D and TaMYB96-5D that bound directly to the conserved motif CAACCA in promoters of the cuticular wax biosynthesis genes TaCER1-6A, TaCER1-1A, and fatty acyl-CoA reductase4. Collectively, these results suggest that TaCER1-6A is required for C27, C29, C31, and C33 alkanes biosynthesis and improves drought tolerance in wheat.


Assuntos
Secas , Triticum , Triticum/fisiologia , Alcanos/metabolismo , Regulação da Expressão Gênica de Plantas , Ceras/metabolismo , Folhas de Planta/metabolismo
2.
Plant J ; 106(5): 1468-1483, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33768632

RESUMO

Suberin is a complex hydrophobic polymer of aliphatic and phenolic compounds which controls the movement of gases, water, and solutes and protects plants from environmental stresses and pathogenic infection. The synthesis and regulatory pathways of suberin remain unknown in Brachypodium distachyon. Here we describe the identification of a B. distachyon gene, BdFAR4, encoding a fatty acyl-coenzyme A reductase (FAR) by a reverse genetic approach, and investigate the molecular relevance of BdFAR4 in the root suberin synthesis of B. distachyon. BdFAR4 is specifically expressed throughout root development. Heterologous expression of BdFAR4 in yeast (Saccharomyces cerevisiae) afforded the production of C20:0 and C22:0 fatty alcohols. The loss-of-function knockout of BdFAR4 by CRISPR/Cas9-mediated gene editing significantly reduced the content of C20:0 and C22:0 fatty alcohols associated with root suberin. In contrast, overexpression of BdFAR4 in B. distachyon and tomato (Solanum lycopersicum) resulted in the accumulation of root suberin-associated C20:0 and C22:0 fatty alcohols, suggesting that BdFAR4 preferentially accepts C20:0 and C22:0 fatty acyl-CoAs as substrates. The BdFAR4 protein was localized to the endoplasmic reticulum in Arabidopsis thaliana protoplasts and Nicotiana benthamiana leaf epidermal cells. BdFAR4 transcript levels can be increased by abiotic stresses and abscisic acid treatment. Furthermore, yeast one-hybrid, dual-luciferase activity, and electrophoretic mobility shift assays indicated that the R2R3-MYB transcription factor BdMYB41 directly binds to the promoter of BdFAR4. Taken together, these results imply that BdFAR4 is essential for the production of root suberin-associated fatty alcohols, especially under stress conditions, and that its activity is transcriptionally regulated by the BdMYB41 transcription factor.


Assuntos
Aldeído Oxirredutases/metabolismo , Brachypodium/genética , Álcoois Graxos/metabolismo , Regulação da Expressão Gênica de Plantas , Lipídeos/biossíntese , Aldeído Oxirredutases/genética , Arabidopsis/enzimologia , Arabidopsis/genética , Arabidopsis/fisiologia , Brachypodium/enzimologia , Brachypodium/fisiologia , Edição de Genes , Técnicas de Inativação de Genes , Mutação com Perda de Função , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/enzimologia , Raízes de Plantas/genética , Raízes de Plantas/fisiologia , Poliésteres/metabolismo , Estresse Fisiológico , Nicotiana/enzimologia , Nicotiana/genética , Nicotiana/fisiologia
3.
J Bioenerg Biomembr ; 53(4): 393-403, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34076840

RESUMO

Inflammation and renal cell apoptosis participate in sepsis-induced acute kidney injury. Previous research found the upregulation of long non-coding RNA Linc-KIAA1737-2 in hypoxia- or inflammation-challenged human proximal tubular epithelial cells, but its role in sepsis-induced acute kidney injury is underexplored. In this research, we found that Linc-KIAA1737-2 could be upregulated in HK-2 human proximal tubular epithelial cells by LPS treatment, and knock-down of this lncRNA significantly attenuated LPS-induced apoptosis in HK-2 cells, while its overexpression showed opposite effect. MiR-27a-3p was confirmed to interact with Linc-KIAA1737-2 in HK-2 cells by RNA pull-down and dual-luciferase assay. MiR-27a-3p mimic transfection significantly attenuated LPS-induced HK-2 cell apoptosis by downregulating the protein levels of TLR4 and NF-κB, which was overturned by overexpression of Linc-KIAA1737-2. Our results suggested that Linc-KIAA1737-2 could promote LPS-induced apoptosis in HK-2 cells, and presumably sepsis-induced acute kidney injury, by regulating the miR-27a-3p/TLR4/NF-κB axis.


Assuntos
Lipopolissacarídeos/metabolismo , MicroRNAs/metabolismo , NF-kappa B/metabolismo , RNA Longo não Codificante/genética , Apoptose , Humanos , Transfecção
4.
Inflamm Res ; 69(7): 645-656, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32342116

RESUMO

OBJECTIVE AND DESIGN: Nowadays, sepsis-induced acute kidney injury (AKI) has gradually become a global problem for its high incidence and increasing mortality. Previous study has reported lncRNA ENST00000452391.1 in sepsis patients. However, its potential biological function and downstream molecular mechanism are still mysterious. METHODS AND RESULTS: Our study found that it was upregulated in sepsis-induced AKI patients, so it was identified as "sepsis-induced kidney injury associated transcript 1 (SIKIAT1)". We used lipopolysaccharide (LPS) stimulated HK-2 cells as an in vitro model to demonstrated that SIKIAT1 acts as a ceRNA for miR-96-3p to enhance FOXA1 expression and promote HK-2 cell apoptosis. CONCLUSION: Therefore, it could be a potential biomarker and therapeutic target for sepsis-induced AKI in the development of disease.


Assuntos
Apoptose/fisiologia , Fator 3-alfa Nuclear de Hepatócito/fisiologia , Nefropatias/etiologia , MicroRNAs/fisiologia , Sepse/complicações , Linhagem Celular , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Fator 3-alfa Nuclear de Hepatócito/genética , Humanos , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Nefropatias/patologia , Lipopolissacarídeos/farmacologia , MicroRNAs/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/fisiologia , Sepse/genética , Sepse/patologia , Transfecção
5.
BMC Infect Dis ; 20(1): 549, 2020 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-32727456

RESUMO

BACKGROUND: We aimed to report the epidemiological and clinical characteristics of hospitalized patients with coronavirus disease-19 (COVID-19) in Zengdu District, Hubei Province, China. METHODS: Clinical data on COVID-19 inpatients in Zengdu Hospital from January 27 to March 11, 2020 were collected; this is a community hospital in an area surrounding Wuhan and supported by volunteer doctors. All hospitalized patients with COVID-19 were included in this study. The epidemiological findings, clinical features, laboratory findings, radiologic manifestations, and clinical outcomes of these patients were analyzed. The patients were followed up for clinical outcomes until March 22, 2020. Severe COVID-19 cases include severe and critical cases diagnosed according to the seventh edition of China's COVID-19 diagnostic guidelines. Severe and critical COVID-19 cases were diagnosed according to the seventh edition of China's COVID-19 diagnostic guidelines. RESULTS: All hospitalized COVID-19 patients, 276 (median age: 51.0 years), were enrolled, including 262 non-severe and 14 severe patients. The proportion of patients aged over 60 years was higher in the severe group (78.6%) than in the non-severe group (18.7%, p < 0.01). Approximately a quarter of the patients (24.6%) had at least one comorbidity, such as hypertension, diabetes, or cancer, and the proportion of patients with comorbidities was higher in the severe group (85.7%) than in the non-severe group (21.4%, p < 0.01). Common symptoms included fever (82.2% [227/276]) and cough (78.0% [218/276]). 38.4% (106/276) of the patients had a fever at the time of admission. Most patients (94.9% [204/276]) were cured and discharged; 3.6% (10/276) deteriorated to a critical condition and were transferred to another hospital. The median COVID-19 treatment duration and hospital stay were 14.0 and 18.0 days, respectively. CONCLUSIONS: Most of the COVID-19 patients in Zengdu had mild disease. Older patients with underlying diseases were at a higher risk of progression to severe disease. The length of hospital-stay and antiviral treatment duration for COVID-19 were slightly longer than those in Wuhan. This work will contribute toward an understanding of COVID-19 characteristics in the areas around the core COVID-19 outbreak region and serve as a reference for decision-making for epidemic prevention and control in similar areas.


Assuntos
Betacoronavirus/patogenicidade , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/fisiopatologia , Tempo de Internação/estatística & dados numéricos , Pneumonia Viral/epidemiologia , Pneumonia Viral/fisiopatologia , Adolescente , Adulto , COVID-19 , Criança , Pré-Escolar , China/epidemiologia , Comorbidade , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/tratamento farmacológico , Tosse/epidemiologia , Feminino , Febre/epidemiologia , Humanos , Hipertensão/epidemiologia , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/diagnóstico , Estudos Retrospectivos , SARS-CoV-2 , Resultado do Tratamento , Adulto Jovem , Tratamento Farmacológico da COVID-19
6.
Int Wound J ; 17(1): 100-106, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31701658

RESUMO

The objective of this study is to investigate the mechanism whereby innate immune molecule surfactant protein D (SP-D) attenuates sepsis-induced acute kidney injury (AKI) through modulating apoptosis and nuclear factor kappa-B (NFκB)-mediated inflammation. In the present study, a mouse sepsis model was established by cecal ligation and puncture in SP-D knockout (KO) mice and wild-type (WT) mice. A sham-operated group was included as the control. The experimental materials were extracted 6 and 24 hours postoperatively. The plasma levels of tumour necrosis factor alpha (TNF-α) and MCP-1 were determined by enzyme-linked immunosorbent assay (ELISA). Apoptosis was measured by double staining with Annexin V/propidium iodide and flow cytometry. The levels of NFκB in renal tissues were measured by ELISA and Western blotting assay. Apoptosis was detected by TUNEL assays. There were no significant differences in plasma TNF-α levels between the WT sham group and the KO sham group at 6 and 24 hours postoperatively (P < .05), but the levels of TNF-α in the WT sepsis and KO sepsis groups were significantly higher than those in controls (P < .05). The levels of TNF-α in the KO sepsis group were significantly higher than those of the WT sepsis group (P < .05). TNF-α levels in the WT sepsis group and the KO sepsis group at 24 hours postoperatively were significantly higher than those at 6 hours postoperatively (P < .05). The levels of MCP-1 in the WT sepsis group and the KO sepsis group at 6 and 24 hours postoperatively were significantly higher than those in the control group (P < .05), and MCP-1 levels in the KO sepsis group were significantly higher than those in the WT sepsis group (P < .05). MCP-1 levels in the WT sepsis group and the KO sepsis group at 24 hours postoperatively were significantly higher than those at 6 hours postoperatively (P < .05). The expression of SP-D in WT kidneys was significantly lower at 6 and 24 hours postoperatively (P < .05). The number of TUNEL-positive cells in the kidneys from septic SP-D KO mice was significantly higher (P < .05). The levels of NFκB in septic mice were significantly increased at 6 and 24 hours after induction of sepsis compared with the sham-operated group compared with those of septic SP-D KO mice and WT mice (P < .05). Innate immune molecule SP-D significantly decreased plasma levels of inflammatory cytokines in mice and attenuated sepsis-induced AKI by inhibiting NFκB activity and apoptosis.


Assuntos
Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/imunologia , Apoptose/efeitos dos fármacos , Inflamação/imunologia , Proteína D Associada a Surfactante Pulmonar/uso terapêutico , Surfactantes Pulmonares/uso terapêutico , Sepse/complicações , Animais , Modelos Animais de Doenças , Imunidade Inata/efeitos dos fármacos , Masculino , Camundongos , Camundongos Knockout , NF-kappa B/imunologia
7.
Research (Wash D C) ; 2022: 9830457, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35356767

RESUMO

Noninvasive brain-computer interface (BCI) has been extensively studied from many aspects in the past decade. In order to broaden the practical applications of BCI technique, it is essential to develop electrodes for electroencephalogram (EEG) collection with advanced characteristics such as high conductivity, long-term effectiveness, and biocompatibility. In this study, we developed a silver-nanowire/PVA hydrogel/melamine sponge (AgPHMS) semidry EEG electrode for long-lasting monitoring of EEG signal. Benefiting from the water storage capacity of PVA hydrogel, the electrolyte solution can be continuously released to the scalp-electrode interface during used. The electrolyte solution can infiltrate the stratum corneum and reduce the scalp-electrode impedance to 10 kΩ-15 kΩ. The flexible structure enables the electrode with mechanical stability, increases the wearing comfort, and reduces the scalp-electrode gap to reduce contact impedance. As a result, a long-term BCI application based on measurements of motion-onset visual evoked potentials (mVEPs) shows that the 3-hour BCI accuracy of the new electrode (77% to 100%) is approximately the same as that of conventional electrodes supported by a conductive gel during the first hour. Furthermore, the BCI system based on the new electrode can retain low contact impedance for 10 hours on scalp, which greatly improved the ability of BCI technique.

8.
IEEE Trans Pattern Anal Mach Intell ; 31(9): 1670-84, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19574626

RESUMO

Iris segmentation is an essential module in iris recognition because it defines the effective image region used for subsequent processing such as feature extraction. Traditional iris segmentation methods often involve an exhaustive search of a large parameter space, which is time consuming and sensitive to noise. To address these problems, this paper presents a novel algorithm for accurate and fast iris segmentation. After efficient reflection removal, an Adaboost-cascade iris detector is first built to extract a rough position of the iris center. Edge points of iris boundaries are then detected, and an elastic model named pulling and pushing is established. Under this model, the center and radius of the circular iris boundaries are iteratively refined in a way driven by the restoring forces of Hooke's law. Furthermore, a smoothing spline-based edge fitting scheme is presented to deal with noncircular iris boundaries. After that, eyelids are localized via edge detection followed by curve fitting. The novelty here is the adoption of a rank filter for noise elimination and a histogram filter for tackling the shape irregularity of eyelids. Finally, eyelashes and shadows are detected via a learned prediction model. This model provides an adaptive threshold for eyelash and shadow detection by analyzing the intensity distributions of different iris regions. Experimental results on three challenging iris image databases demonstrate that the proposed algorithm outperforms state-of-the-art methods in both accuracy and speed.


Assuntos
Algoritmos , Inteligência Artificial , Biometria/métodos , Interpretação de Imagem Assistida por Computador/métodos , Iris/anatomia & histologia , Reconhecimento Automatizado de Padrão/métodos , Técnica de Subtração , Humanos , Aumento da Imagem/métodos
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