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1.
Opt Express ; 32(4): 5760-5769, 2024 Feb 12.
Article in English | MEDLINE | ID: mdl-38439294

ABSTRACT

Heme is the prosthetic group for cytochrome that exists in nearly all living organisms and serves as a vital component of human red blood cells (RBCs). Tunable optical nonlinearity in suspensions of RBCs has been demonstrated previously, however, the nonlinear optical response of a pure heme (without membrane structure) solution has not been studied to our knowledge. In this work, we show optical nonlinearity in two common kinds of heme (i.e., hemin and hematin) solutions by a series of experiments and numerical simulations. We find that the mechanism of nonlinearity in heme solutions is distinct from that observed in the RBC suspensions where the nonlinearity can be easily tuned through optical power, concentration, and the solution properties. In particular, we observe an unusual phenomenon wherein the heme solution exhibits negative optical nonlinearity and render self-collimation of a focused beam at specific optical powers, enabling shape-preserving propagation of light to long distances. Our results may have potential applications in optical imaging and medical diagnosis through blood.


Subject(s)
Erythrocytes , Heme , Humans , Optical Imaging
2.
New Phytol ; 241(4): 1732-1746, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38037458

ABSTRACT

Lysine acetylation is an evolutionarily conserved and widespread post-translational modification implicated in the regulation of multiple metabolic processes, but its function remains largely unknown in plant pathogenic fungi. A comprehensive analysis combined with proteomic, molecular and cellular approaches was presented to explore the roles of cytoplasmic acetylation in Fusarium oxsysporum f.sp. lycopersici (Fol). The divergent cytoplasmic deacetylase FolSir2 was biochemically characterized, which is contributing to fungal virulence. Based on this, a total of 1752 acetylated sites in 897 proteins were identified in Fol via LC-MS/MS analysis. Further analyses of the quantitative acetylome revealed that 115 proteins representing two major pathways, translational and ribosome biogenesis, were hyperacetylated in the ∆Folsir2 strain. We experimentally examined the regulatory roles of FolSir2 on K271 deacetylation of FolGsk3, a serine/tyrosine kinase implicated in a variety of cellular functions, which was found to be crucial for the activation of FolGsk3 and thus modulated Fol pathogenicity. Cytoplasmic deacetylation by FolSir2 homologues has a similar function in Botrytis cinerea and likely other fungal pathogens. These findings reveal a conserved mechanism of silent information regulator 2-mediated cytoplasmic deacetylation that is involved in plant-fungal pathogenicity, providing a candidate target for designing broad-spectrum fungicides to control plant diseases.


Subject(s)
Fusarium , Proteomics , Chromatography, Liquid , Tandem Mass Spectrometry , Fungi , Protein Processing, Post-Translational , Plant Diseases/microbiology
3.
Opt Lett ; 48(22): 5947-5950, 2023 Nov 15.
Article in English | MEDLINE | ID: mdl-37966759

ABSTRACT

We demonstrate multiple flatbands and compact localized states (CLSs) in a photonic super-Kagome lattice (SKL) that exhibits coexistence of singular and nonsingular flatbands within its unique band structure. Specifically, we find that the upper two flatbands of an SKL are singular-characterized by singularities due to band touching with their neighboring dispersive bands at the Brillouin zone center. Conversely, the lower three degenerate flatbands are nonsingular and remain spectrally isolated from other dispersive bands. The existence of such two distinct types of flatbands is experimentally demonstrated by observing stable evolution of the CLSs with various geometrical shapes in a laser-written SKL. We also discuss the classification of the flatbands in momentum space, using band-touching singularities of the Bloch wave functions. Furthermore, we validate this classification in real space based on unit cell occupancy of the CLSs in a single SKL plaquette. These results may provide insights for the study of flatband transport, dynamics, and nontrivial topological phenomena in other relevant systems.

4.
Microbiol Spectr ; 11(4): e0108323, 2023 08 17.
Article in English | MEDLINE | ID: mdl-37378525

ABSTRACT

Verticillium dahliae is a soilborne fungal pathogen that causes disease on many economically important crops. Based on the resistance or susceptibility of differential cultivars in tomato, isolates of V. dahliae are divided into three races. Avirulence (avr) genes within the genomes of the three races have also been identified. However, the functional role of the avr gene in race 3 isolates of V. dahliae has not been characterized. In this study, bioinformatics analysis showed that VdR3e, a cysteine-rich secreted protein encoded by the gene characterizing race 3 in V. dahliae, was likely obtained by horizontal gene transfer from the fungal genus Bipolaris. We demonstrate that VdR3e causes cell death by triggering multiple defense responses. In addition, VdR3e localized at the periphery of the plant cell and triggered immunity depending on its subcellular localization and the cell membrane receptor BAK1. Furthermore, VdR3e is a virulence factor and shows differential pathogenicity in race 3-resistant and -susceptible hosts. These results suggest that VdR3e is a virulence factor that can also interact with BAK1 as a pathogen-associated molecular pattern (PAMP) to trigger immune responses. IMPORTANCE Based on the gene-for-gene model, research on the function of avirulence genes and resistance genes has had an unparalleled impact on breeding for resistance in most crops against individual pathogens. The soilborne fungal pathogen, Verticillium dahliae, is a major pathogen on many economically important crops. Currently, avr genes of the three races in V. dahliae have been identified, but the function of avr gene representing race 3 has not been described. We investigated the characteristics of VdR3e-mediated immunity and demonstrated that VdR3e acts as a PAMP to activate a variety of plant defense responses and induce plant cell death. We also demonstrated that the role of VdR3e in pathogenicity was host dependent. This is the first study to describe the immune and virulence functions of the avr gene from race 3 in V. dahliae, and we provide support for the identification of genes mediating resistance against race 3.


Subject(s)
Ascomycota , Verticillium , Virulence/genetics , Verticillium/genetics , Plant Immunity , Virulence Factors/genetics , Virulence Factors/metabolism , Plant Diseases/microbiology
5.
Front Microbiol ; 13: 1040302, 2022.
Article in English | MEDLINE | ID: mdl-36338032

ABSTRACT

The secretion of peptidases from several pathogens has been reported, but the biological function of these proteins in plant-pathogen interactions is poorly understood. Fusarium oxysporum, a soil-borne plant pathogenic fungus that causes Fusarium wilt in its host, can secrete proteins into host plant cells during the infection process to interfere with the host plant defense response and promote disease occurrence. In this study, we identified a peptidase, FoAPY1, that could be secreted from F. oxysporum depending on the N-terminal signal peptide of the protein. FoAPY1 belongs to the peptidase M28 family and exerts peptidase activity in vitro. Furthermore, the FoAYP1 gene knockout strain (∆FoAYP1) presented reduced virulence to tomato plants, but its mycelial growth and conidiation were unchanged. Moreover, FoAYP1 overexpression tomato seedlings exhibited enhanced susceptibility to F. oxysporum and Botrytis cinerea strains. These data demonstrated that FoAYP1 contributes to the virulence of F. oxysporum may through peptidase activity against host plant proteins.

6.
Dis Markers ; 2022: 3823368, 2022.
Article in English | MEDLINE | ID: mdl-35942131

ABSTRACT

Objective: This study focused on elucidating the influence of early multidisciplinary collaboration on preventing intensive care unit- (ICU-) acquired weakness (AW) in critically ill patients (CIPs). Methods: Ninety-five CIPs admitted between December 2018 and December 2021 were selected and assigned to the following two groups according to the intervention pattern: the control group (the Con; n = 40) treated with routine early rehabilitation intervention, and the research group (the Res; n = 55) intervened by early multidisciplinary collaborative intervention. The incidence of complications (ICU-AW, deep vein thrombosis (DVT), and pressure ulcers (PSs)) and recovery indices (days of ventilator use, ICU treatment time, and length of hospital stay (LOS)) were recorded. Besides, patients' activity function and quality of life (QoL) were evaluated and compared, among which the former was evaluated by the Barthel Index (BI), ICU Mobility Scale (IMS), and Medical Research Council (MRC) Scale, and the latter was assessed by the World Health Organization Quality of Life Assessment (100-item version) (WHOQOL-100). Results: The data identified statistically a lower incidence of complications (ICU-AW, DVT, and PSs) and shorter time of ventilator use, ICU residence, and LOS in the Res compared with the Con. In addition, BI, IMS, MRC, and WHOQOL-100 scores in the Res elevated statistically after treatment and were higher than those of the Con. Conclusions: Early multidisciplinary collaboration can validly prevent ICU-AW in CIPs, reduce the incidence of DVT and PSs, and promote patients' rehabilitation, mobility, and QoL.


Subject(s)
Critical Illness , Quality of Life , Humans , Intensive Care Units , Length of Stay , Muscle Weakness/etiology , Muscle Weakness/prevention & control
7.
Nanomaterials (Basel) ; 12(14)2022 Jul 14.
Article in English | MEDLINE | ID: mdl-35889634

ABSTRACT

In today's age of resource scarcity, the low-cost development and utilization of renewable energy, e.g., hydrogen energy, have attracted much attention in the world. In this work, cheap natural halloysite nanotubes (HNTs) were modified with γ-aminopropyltriethoxysilane (APTES), and the functionalized HNTs were used as to support metal (Pd, Au, Ag) catalysts for dehydrogenation of formic acid (DFA). The supports and fabricated catalysts were characterized with ICP, FT-IR, XRD, XPS and TEM. The functional groups facilitate the anchoring of metal particles to the supports, which brings about the high dispersion of metallic particles in catalysts. The catalysts show high activity against DFA and exhibit selectivity of 100% toward H2 at room temperature or less. The interactions between active centers and supports were investigated by evaluation and comparison of the catalytic performances of Pd/NH2-HNTs, PdAg/NH2-HNTs and PdAu/NH2-HNTs for DFA.

8.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 30(2): 481-486, 2022 Apr.
Article in Chinese | MEDLINE | ID: mdl-35395983

ABSTRACT

OBJECTIVE: To investigate the prognostic value of hemopoietic scoring system composed of hemoglobin (HB), platelet count (PLT) and mean corpuscular volume (MCV) in MM patients and its correlation with curative effect. METHODS: The clinical data of 172 newly diagnosed MM patients treated by bortezomib as the first-line regimen in our hospital from May 2014 to December 2019 were collected, three variables (HB≤100 g/L, PLT≤150×109/L, MCV≥96 fl) were introduced, each variable was distributed 1 score, the patients were divided into four groups (0, 1, 2 and 3 points in group 1, 2, 3 and 4, respectively), and the clinical characteristics and prognosis of the patients in the four groups were analyzed. The initial efficacy evaluation after 3-4 courses of treatment was carried out, and the curative effect of the patients in the different hematopoiesis score groups were compared. RESULTS: The median OS time of the patients in group 1, 2, 3 and 4 was 27.0, 22.5, 20.7 and 18.1 months, while the median PFS time were 23.0, 19.0, 18.0 and 14.0 months, respectively. The OS and PFS of the patients in low score group were significantly better than those in high score group (P=0.045, P=0.048). There was no significant difference in the curative effect of the patients treated by bortezomib after 3-4 courses (P>0.05). CONCLUSION: Hematopoiesis score can preliminarily predict the overall survival of newly diagnosed MM patients, but there is no significant difference between different scoring groups in the initial curative effect.


Subject(s)
Multiple Myeloma , Bortezomib/therapeutic use , Erythrocyte Indices , Hemoglobins/therapeutic use , Humans , Multiple Myeloma/diagnosis , Prognosis , Retrospective Studies
9.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 30(1): 141-145, 2022 Feb.
Article in Chinese | MEDLINE | ID: mdl-35123617

ABSTRACT

OBJECTIVE: To investigate the clinical characteristics and prognosis of multiple myeloma patients with myelofibrosis. METHODS: The clinical data of 263 patients with multiple myeloma (including 92 patients with myelofibrosis) treated in the department of hematology of our hospital from January 1, 2016 to June 31, 2020 were collected and retrospectively analyzed, the patients were divided into combined group and uncombined group. The MM stage, MM type, genetic characteristics and therapeutic effect of the patients in combined group and uncombined group were observed, and the relationship between the curative effect and the degree of myelofibrosis change of the patients in combined group was analyzed. RESULTS: There was no statistically difference in the MM staging and classification between multiple myeloma patients with or without myelofibrosis (P>0.05). The positive rate of FISH results of the patients in combined group was significantly higher than those in uncombined group, and was significantly correlated to 1q21 amplification, D13S319 deletion, and IgH breakage (P<0.05). After treatment, the effective rate of the patients in uncombined group was significantly higher than those in combined group, and the degree of fibrosis in the effective patients in combined group was significantly reduced. CONCLUSION: The survival rate of the patients with multiple myeloma complicated with myelofibrosis is shorter than that of the patients without myelofibrosis, and the overall prognosis is poor.


Subject(s)
Multiple Myeloma , Primary Myelofibrosis , Chromosome Aberrations , Humans , Multiple Myeloma/complications , Primary Myelofibrosis/complications , Prognosis , Retrospective Studies
10.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 30(1): 170-174, 2022 Feb.
Article in Chinese | MEDLINE | ID: mdl-35123622

ABSTRACT

OBJECTIVE: To compare the efficacy and safety of different chemotherapy regimens in elderly multiple myeloma (MM) patients with different Frailty scores. METHODS: The clinical data of elderly patients with MM were retrospectively analyzed, including age, treatment regimen, efficacy, adverse reactions, and the Frailty score included in the activity of daily living score, the instrumental activity of daily living scale and the Charlson comorbidity index. The patients were divided into fit group, mediate fit group and frail group according to the scoring standard. The treatment efficiency and adverse reaction rates of elderly MM with different physical conditions treated by different chemotherapy regimens were analyzed. RESULTS: Among the 70 patients, the effective rates of the patients in fit group, the mediate fit group, and the frail group were 79.5%, 81%, and 40%, and the effective rates of the fit patients in double and triple groups were 54.5% and 89.3%, 70% and 90.9% for mediate fit patients, 42.9% and 33.3% for frail patients, the triple regimen in fit patients showed obvious advantages, and the difference showed statistically significant (P<0.05), while the efficacy for mediate patients and frail patients showed no significant difference. During the induction of bortezomib, the incidence of adverse reactions for the patients in the triple group (78.6%) was higher than 67.9% in the double group, and the difference showed no statistically significant (P>0.05).There was no significant difference in the 1-year overall survival rate of the patients and with molecular genetic abnormalities among each groups. CONCLUSION: The therapeutic effect is related to the patient's physical condition. For patients with healthy physique, the triple regimen should be used first. For patients with weak physical constitution, the chemotherapy regimen with low drug toxicity should be selected for safety.


Subject(s)
Frailty , Multiple Myeloma , Aged , Bortezomib , Humans , Multiple Myeloma/drug therapy , Retrospective Studies
11.
J Colloid Interface Sci ; 608(Pt 1): 366-377, 2022 Feb 15.
Article in English | MEDLINE | ID: mdl-34626982

ABSTRACT

Photocatalytic water spitting is one way of hydrogen production from energy conservation and emission reduction. However, the activities of most photocatalytic materials need to be enhanced by cocatalysts. In this study, we explored to control the photocatalytic hydrogen evolution (PHE) ability of cadmium sulfide (CdS) without any cocatalysts by temperature and largely improve its photocatalytic ability. It was experimentally found the activity of CdS without cocatalysts under heating conditions (<100 °C) was much higher than that at room temperature, and increased first and then decreased, with a maximum at 50 °C (169716 umol/h, 68.2 % , λ = 450 nm). Therefore, it is convenient to control the hydrogen production activity of CdS by temperature. The large increment of photocatalytic activity was realized because the temperature complemented the shortcomings of semiconductors in light absorption, and together with light radiation, increased the electron migration rate and density, quantity of surface adsorbed H3O+ and number of active sites, prolonged the living of electrons, and reduced the overpotential of water splitting and the reverse reactions. Heating brings the above advantages, but also exacerbates the recombination of electron-hole pairs. Therefore, the activity shows an extreme value along with the temperature rise. This work experimentally proves temperature control is one of the most efficient and simple ways to largely enhance the PHE ability.


Subject(s)
Hydrogen , Light , Cadmium Compounds , Catalysis , Sulfides , Temperature
12.
Shock ; 57(1): 140-150, 2022 01 01.
Article in English | MEDLINE | ID: mdl-34265832

ABSTRACT

OBJECTIVES: Mechanical stretch-induced alveolar epithelial cell (AEC) apoptosis participates in the onset of ventilator-induced lung injury (VILI). In this study, we explored whether death-associated protein kinase 1 (DAPK1) mediated cyclic stretch (CS)-induced AEC apoptosis and VILI though P53 pathway. MATERIALS AND METHODS: AEC apoptosis was induced by CS using the FX-5000T Flexercell Tension Plus system. C57BL/6 mouse received high tidal volume ventilation to build VILI model. DAPK1 inhibitor, P53 inhibitor, or DAPK1 plasmid was used to regulate the expression of DAPK1 and P53, respectively. Flow cytometery was performed to assay cell apoptosis and the changes of mitochondrial membrane potential (MMP); immunoblotting was adopted to analyze related protein expression. The binding of related proteins was detected by coimmunoprecipitation; AEC apoptosis in vivo was determined by immunohistochemistry assay. RESULTS: CS promoted AEC apoptosis, increased DAPK1 and P53 expression, and induced the binding of DAPK1 and P53; inhibition of DAPK1 or P53 reduced CS-induced AEC apoptosis, suppressed the expression of Bax, increased Bcl-2 level, and stabilized MMP; AEC apoptosis and the level of P53 were both increased after overexpressing of DAPK1. Moreover, DAPK1 plasmid transfection also promoted the expression of Bax and the change of MMP, but decreased the level of Bcl-2. Inhibition of DAPK1 or P53 in vivo alleviated high tidal volume ventilation-induced AEC apoptosis and lung injury. CONCLUSIONS: DAPK1 contributes to AEC apoptosis and the onset of VILI though P53 and its intrinsic pro-apoptotic pathway. Inhibition of DAPK1 or P53 alleviates high tidal volume ventilation-induced lung injury and AEC apoptosis.


Subject(s)
Alveolar Epithelial Cells/pathology , Death-Associated Protein Kinases/metabolism , Tumor Suppressor Protein p53/metabolism , Ventilator-Induced Lung Injury , Animals , Apoptosis , Cells, Cultured , Mice, Inbred C57BL , Signal Transduction
13.
Elife ; 102021 12 20.
Article in English | MEDLINE | ID: mdl-34927582

ABSTRACT

Fusarium oxysporum is one of the most important pathogenic fungi with a broad range of plant and animal hosts. The first key step of its infection cycle is conidial germination, but there is limited information available on the molecular events supporting this process. We show here that germination is accompanied by a sharp decrease in expression of FoSir5, an ortholog of the human lysine deacetylase SIRT5. We observe that FoSir5 decrotonylates a subunit of the fungal pyruvate dehydrogenase complex (FoDLAT) at K148, resulting in inhibition of the activity of the complex in mitochondria. Moreover, FoSir5 decrotonylates histone H3K18, leading to a downregulation of transcripts encoding enzymes of aerobic respiration pathways. Thus, the activity of FoSir5 coordinates regulation in different organelles to steer metabolic flux through respiration. As ATP content is positively related to fungal germination, we propose that FoSir5 negatively modulates conidial germination in F. oxysporum through its metabolic impact. These findings provide insights into the multifaceted roles of decrotonylation, catalyzed by FoSir5, that support conidial germination in F. oxysporum.


Subject(s)
Fusarium/growth & development , Fusarium/genetics , Fusarium/metabolism , Mitochondria/metabolism , Spores, Fungal/growth & development , Spores, Fungal/genetics , Spores, Fungal/metabolism , Gene Expression Regulation, Fungal , Mitochondria/genetics , Plant Diseases/microbiology
14.
Front Oncol ; 10: 553332, 2020.
Article in English | MEDLINE | ID: mdl-33194614

ABSTRACT

BACKGROUND: Several studies have reported that hyperinsulinemia plays a part in the etiology of breast cancer. However, no consensus has been reached. Therefore, we conducted a meta-analysis to explore the role of insulin and C-peptide in breast cancer. METHODS: A systematic search in PubMed, Embase, and The Cochrane Library was conducted up to September, 2020. Standardized mean differences (SMDs) with 95% confidence intervals (CIs) were used to measure effect sizes. Publication bias was assessed using the Egger test. Stability of these results was evaluated using sensitivity analyses. RESULTS: Fourteen articles including 27,084 cases and five articles including 2,513 cases were extracted for serum insulin levels and C-peptide levels. We found that C-peptide levels were positively associated with breast cancer with overall SMD = 0.37 (95% CI = 0.09-0.65, I2 = 89.1%). Subgroup analysis by control source illustrated a positive relationship between breast cancer and C-peptide levels in population-based control. Subgroup analysis by C-peptide level indicated a positive correlation between breast cancer and C-peptide levels no matter C-peptide levels in case group is ≤3 ng/ml or >3 ng/ml. Subgroup analysis by age showed that C-peptide level positively correlated to breast cancer in women between the ages of 50 and 60. However, we did not identify any relationship between breast cancer and insulin levels (SMD = 0.22, 95% CI = -0.06-0.50, I2 = 97.3%). CONCLUSION: This meta-analysis demonstrated that C-peptide levels were positively related to breast cancer in women, and no relationship between insulin levels and breast cancer was found.

15.
Front Microbiol ; 11: 559440, 2020.
Article in English | MEDLINE | ID: mdl-33013791

ABSTRACT

Fusarium oxysporum f. sp. lycopersici (Fol) is the causal agent of Fusarium wilt disease in tomato. Proteins secreted by this pathogen during initial host colonization largely determine the outcome of pathogen-host interactions. Lysine acetylation (Kac) plays a vital role in the functions of many proteins, but little is known about Kac in Fol secreted proteins. In this study, we analyzed lysine acetylation of the entire Fol secretome. Using high affinity enrichment of Kac peptides and LC-MS/MS analysis, 50 potentially secreted Fol proteins were identified and acetylation sites determined. Bioinformatics analysis revealed 32 proteins with canonical N-terminal signal peptide leaders, and most of them were predicted to be enzymes involved in a variety of biological processes and metabolic pathways. Remarkably, all 32 predicted secreted proteins were novel and encoded on the core chromosomes rather than on the previously identified LS pathogenicity chromosomes. Homolog scanning of the secreted proteins among 40 different species revealed 4 proteins that were species specific, 3 proteins that were class-specific in the Ascomycota phylum, and 25 proteins that were more widely conserved genes. These secreted proteins provide a starting resource for investigating putative novel pathogenic genes, with 26 up-regulated genes encoding Kac proteins that may play an important role during initial symptomless infection stages.

16.
Front Cardiovasc Med ; 7: 150, 2020.
Article in English | MEDLINE | ID: mdl-33102532

ABSTRACT

Background: Coronavirus disease 2019 (COVID-19) is rapidly spreading and resulting in a significant loss of life around the world. However, specific information characterizing cardiovascular changes in COVID-19 is limited. Methods: In this single-centered, observational study, we enrolled 38 adult patients with COVID-19 from February 10 to March 13, 2020. Clinical records, laboratory findings, echocardiography, and electrocardiogram reports were collected and analyzed. Results: Of the 38 patients enrolled, the median age was 68 years [interquartile range (IQR), 55-74] with a slight female majority (21, 55.3%). Nineteen (50.0%) patients had hypertension. Seven (33.3%) had ST-T segment and T wave changes, and four (19%) had sinus tachycardia. Twenty (52.6%) had an increase in ascending aorta (AAO) diameter, 22 (57.9%) had an increase in left atrium (LA) size, and 28 (73.7%) presented with ventricular diastolic dysfunction. Correlation analysis showed that the AAO diameter was significantly associated with C-reactive protein (r = 0.4313) and creatine kinase-MB (r = 0.0414). LA enlargement was significantly associated with C-reactive protein (r = 0.4377), brain natriuretic peptide (r = 0.7612), creatine kinase-MB (r = 0.4940), and aspartate aminotransferase (r = 0.2947). Lymphocyte count was negatively associated with the AAO diameter (r = -0.5329) and LA enlargement (r = -0.3894). Conclusions: Hypertension was a common comorbidity among hospitalized patients with COVID-19, and cardiac injury was the most common complication. Changes in cardiac structure and function manifested mainly in the left heart and AAO in these patients. Abnormal AAO and LA size were found to be associated with severe inflammation and cardiac injury. Alternatively, ascending aortic dilation and LA enlargement might be present before infection but characterized the patient at risk for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.

17.
Anesthesiology ; 133(4): 905-918, 2020 10 01.
Article in English | MEDLINE | ID: mdl-32930731

ABSTRACT

BACKGROUND: Alveolar epithelial cell apoptosis is implicated in the onset of ventilator-induced lung injury. Death-associated protein kinase 1 (DAPK1) is associated with cell apoptosis. The hypothesis was that DAPK1 participates in ventilator-induced lung injury through promoting alveolar epithelial cell apoptosis. METHODS: Apoptosis of mouse alveolar epithelial cell was induced by cyclic stretch. DAPK1 expression was altered (knockdown or overexpressed) in vitro by using a small interfering RNA or a plasmid, respectively. C57/BL6 male mice (n = 6) received high tidal volume ventilation to establish a lung injury model. Adeno-associated virus transfection of short hairpin RNA and DAPK1 inhibitor repressed DAPK1 expression and activation in lungs, respectively. The primary outcomes were alveolar epithelial cell apoptosis and lung injury. RESULTS: Compared with the control group, the 24-h cyclic stretch group showed significantly higher alveolar epithelial cell apoptotic percentage (45 ± 4% fold vs. 6 ± 1% fold; P < 0.0001) and relative DAPK1 expression, and this group also demonstrated a reduced apoptotic percentage after DAPK1 knockdown (27 ± 5% fold vs. 53 ± 8% fold; P < 0.0001). A promoted apoptotic percentage in DAPK1 overexpression was observed without stretching (49 ± 6% fold vs. 14 ± 3% fold; P < 0.0001). Alterations in B-cell lymphoma 2 and B-cell lymphoma 2-associated X are associated with DAPK1 expression. The mice subjected to high tidal volume had higher DAPK1 expression and alveolar epithelial cell apoptotic percentage in lungs compared with the low tidal volume group (43 ± 6% fold vs. 4 ± 2% fold; P < 0.0001). Inhibition of DAPK1 through adeno-associated virus infection or DAPK1 inhibitor treatment appeared to be protective against lung injury with reduced lung injury score, resolved pulmonary inflammation, and repressed alveolar epithelial cell apoptotic percentage (47 ± 4% fold and 48 ± 6% fold; 35 ± 5% fold and 34 ± 4% fold; P < 0.0001, respectively). CONCLUSIONS: DAPK1 promotes the onset of ventilator-induced lung injury by triggering alveolar epithelial cell apoptosis through intrinsic apoptosis pathway in mice.


Subject(s)
Alveolar Epithelial Cells/metabolism , Apoptosis/physiology , Death-Associated Protein Kinases/biosynthesis , Ventilator-Induced Lung Injury/metabolism , Alveolar Epithelial Cells/pathology , Animals , Cells, Cultured , Death-Associated Protein Kinases/deficiency , Death-Associated Protein Kinases/physiology , Male , Mice , Mice, Inbred C57BL , Ventilator-Induced Lung Injury/pathology
18.
Mol Med Rep ; 22(5): 3767-3776, 2020 Nov.
Article in English | MEDLINE | ID: mdl-32901885

ABSTRACT

Type 1 diabetes mellitus (T1DM) is an autoimmune disorder for which the only effective therapy is insulin replacement. Hyperbaric oxygen (HBO) therapy has demonstrated potential in improving hyperglycemia and as a treatment option for T1DM. Ghrelin and HBO have been previously reported to exert proliferative, anti­apoptotic and anti­inflammatory effects in pancreatic cells. The present study investigated the mechanism underlying HBO­ and ghrelin system­mediated regulation of glucose metabolism. Male C57BL/6 mice were intraperitoneally injected with streptozotocin (STZ; 150 mg/kg) to induce T1DM before the diabetic mice were randomly assigned into the T1DM and T1DM + HBO groups. Mice in the T1DM + HBO group received HBO (1 h; 100% oxygen; 2 atmospheres absolute) daily for 2 weeks. Significantly lower blood glucose levels and food intake were observed in mice in the T1DM + HBO group. Following HBO treatment, islet ß­cell area were increased whereas those of α­cell were decreased in the pancreas. In addition, greater hepatic glycogen storage in liver was observed, which coincided with higher pancreatic glucose transporter 2 (GLUT2) expression levels and reduced hepatic GLUT2 membrane trafficking. There were also substantially higher total plasma ghrelin concentrations and gastric ghrelin­O­acyl transferase (GOAT) expression levels in mice in the T1DM + HBO group. HBO treatment also abolished reductions in pancreatic GOAT expression levels in T1DM mice. Additionally, hepatic growth hormone secretagogue receptor­1a levels were found to be lower in mice in the T1DM + HBO group compared with those in the T1DM group. These results suggest that HBO administration improved glucose metabolism in a STZ­induced T1DM mouse model. The underlying mechanism involves improved insulin­release, glucose­sensing and regulation of hepatic glycogen storage, an observation that was also likely dependent on the ghrelin signalling system.


Subject(s)
Diabetes Mellitus, Experimental/therapy , Diabetes Mellitus, Type 1/therapy , Ghrelin/metabolism , Hyperbaric Oxygenation/methods , Animals , Blood Glucose/drug effects , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Type 1/chemically induced , Diabetes Mellitus, Type 1/metabolism , Glucose Transporter Type 2/metabolism , Islets of Langerhans/drug effects , Islets of Langerhans/metabolism , Male , Mice , Mice, Inbred C57BL , Streptozocin , Treatment Outcome
19.
Mol Plant Microbe Interact ; 33(10): 1242-1251, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32689887

ABSTRACT

Histone acetyltransferase plays a critical role in transcriptional regulation by increasing accessibility of target genes to transcriptional activators. Botrytis cinerea is an important necrotrophic fungal pathogen with worldwide distribution and a very wide host range, but little is known of how the fungus regulates the transition from saprophytic growth to infectious growth. Here, the function of BcSas2, a histone acetyltransferase of B. cinerea, was investigated. Deletion of the BcSAS2 gene resulted in significantly reduced acetylation levels of histone H4, particularly of H4K16ac. The deletion mutant ΔBcSas2.1 was not only less pathogenic but also more sensitive to oxidative stress than the wild-type strain. RNA-Seq analysis revealed that a total of 13 B. cinerea genes associated with pathogenicity were down-regulated in the ΔBcSas2.1 mutant. Independent knockouts of two of these genes, BcXYGA (xyloglucanase) and BcCAT (catalase), led to dramatically decreased virulence and hypersensitivity to oxidative stress, respectively. Chromatin immunoprecipitation followed by quantitative PCR confirmed that BcSas2 bound directly to the promoter regions of both these pathogenicity-related genes. These observations indicated that BcSas2 regulated the transcription of pathogenicity-related genes by controlling the acetylation level of H4K16, thereby affecting the virulence and oxidative sensitivity of B. cinerea.


Subject(s)
Botrytis/physiology , Histones , Oxidative Stress , Acetylation , Botrytis/genetics , Botrytis/pathogenicity , Catalase/genetics , Genes, Fungal , Glycoside Hydrolases/genetics , Histones/genetics , Plant Diseases/microbiology , Virulence
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