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1.
Blood ; 143(26): 2778-2790, 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38603632

ABSTRACT

ABSTRACT: Notch signaling regulates cell-fate decisions in several developmental processes and cell functions. However, the role of Notch in hepatic thrombopoietin (TPO) production remains unclear. We noted thrombocytopenia in mice with hepatic Notch1 deficiency and so investigated TPO production and other features of platelets in these mice. We found that the liver ultrastructure and hepatocyte function were comparable between control and Notch1-deficient mice. However, the Notch1-deficient mice had significantly lower plasma TPO and hepatic TPO messenger RNA levels, concomitant with lower numbers of platelets and impaired megakaryocyte differentiation and maturation, which were rescued by addition of exogenous TPO. Additionally, JAK2/STAT3 phosphorylation was significantly inhibited in Notch1-deficient hepatocytes, consistent with the RNA-sequencing analysis. JAK2/STAT3 phosphorylation and TPO production was also impaired in cultured Notch1-deficient hepatocytes after treatment with desialylated platelets. Consistently, hepatocyte-specific Notch1 deletion inhibited JAK2/STAT3 phosphorylation and hepatic TPO production induced by administration of desialylated platelets in vivo. Interestingly, Notch1 deficiency downregulated the expression of HES5 but not HES1. Moreover, desialylated platelets promoted the binding of HES5 to JAK2/STAT3, leading to JAK2/STAT3 phosphorylation and pathway activation in hepatocytes. Hepatocyte Ashwell-Morell receptor (AMR), a heterodimer of asialoglycoprotein receptor 1 [ASGR1] and ASGR2, physically associates with Notch1, and inhibition of AMR impaired Notch1 signaling activation and hepatic TPO production. Furthermore, blockage of Delta-like 4 on desialylated platelets inhibited hepatocyte Notch1 activation and HES5 expression, JAK2/STAT3 phosphorylation, and subsequent TPO production. In conclusion, our study identifies a novel regulatory role of Notch1 in hepatic TPO production, indicating that it might be a target for modulating TPO level.


Subject(s)
Hepatocytes , Janus Kinase 2 , Liver , Receptor, Notch1 , Thrombopoietin , Animals , Receptor, Notch1/metabolism , Receptor, Notch1/genetics , Thrombopoietin/metabolism , Thrombopoietin/genetics , Mice , Liver/metabolism , Hepatocytes/metabolism , Janus Kinase 2/metabolism , Janus Kinase 2/genetics , STAT3 Transcription Factor/metabolism , STAT3 Transcription Factor/genetics , Mice, Knockout , Signal Transduction , Phosphorylation , Blood Platelets/metabolism , Mice, Inbred C57BL , Thrombocytopenia/metabolism , Thrombocytopenia/genetics , Thrombocytopenia/pathology
2.
Langmuir ; 39(23): 8234-8243, 2023 Jun 13.
Article in English | MEDLINE | ID: mdl-37262019

ABSTRACT

A microfluidic method was developed to study the ion-specific effect on bubble coalescence in salt solutions. Compared with other reported methods, microfluidics provides a more direct and accurate means of measuring bubble coalescence in salt solutions. We analyzed the coalescence time and approach velocity between bubbles and used simulation to investigate the pressure evolution during the coalescence process. The coalescence time of the three salt solutions decreased initially and then increased as the concentration of the salt solution was increased. The concentration with the shortest coalescence time is considered as the transition concentration (TC) and exhibits ion-specific. At the TC, the change in coalescence time indicates a shift in the effect of salt on bubble coalescence from facilitation to initial inhibition. Meanwhile, it can be seen that the sodium halide solutions significantly inhibit the bubble coalescence and the inhibition capability follows the order NaCl > NaBr > NaI. The results of the approach velocity show that the coalescence time decreases with increasing approach velocity, as well as the approach velocity was strongly influenced by concentration. The approach velocity undergoes a significant change at the TC. Furthermore, simulations of bubble coalescence in the microchannel indicate that the vertical pressure gradient at the center point of the bubble pairs increases as bubbles approach, driving liquid film drainage until bubble coalescence. The pressure at the center of the bubble pair reaches the maximum when the bubbles have first coalesced. It was further revealed that the concentration of the salt solution has a significant impact on the maximum pressure, as evidenced by the observed trend of decreasing pressure values with increasing concentrations.

3.
Am J Transplant ; 21(2): 503-514, 2021 02.
Article in English | MEDLINE | ID: mdl-32805756

ABSTRACT

Boosting T cell immune response posttransplant with checkpoint inhibitors increases graft-versus-lymphoma (GVL) effects at the cost of increasing acute graft-versus-host disease (aGVHD). A combined targeted therapy is needed to decrease checkpoint inhibitors-induced aGVHD without impairing GVL. We studied whether this competition could be avoided by giving concurrent anti-PD-1 antibody and ruxolitinib in allotransplant mouse models in which recipients were challenged with A20 or EL4 lymphoma cells. Given alone the PD-1 antibody increased GVL but did not improve survival of recipients challenged with A20 cells because of increased deaths from aGVHD. Adding ruxolitinib decreased levels of effector T cells and related cytokines. Tbx21- T cells had higher PD-1 levels compared with Tbx21+ T cells. Ruxolitinib increased PD-1 levels on donor T cells by suppressing Tbx21 expression. Ruxolitinib increased apoptosis of T cells which was reversed by the PD-1 antibody. PD-1 antibody preserved expression of granzyme B and cytotoxicity of T cells which were decreased by ruxolitinib. The net result of combined therapy was increased GVL, no increase in aGVHD and increased survival. The combined therapy improved survival of recipients challenged by A20 cells which expressed high level of PD-L1, but not EL4 cells which do not express PD-L1.


Subject(s)
Graft vs Host Disease , Hematopoietic Stem Cell Transplantation , Lymphoma , Animals , Bone Marrow Transplantation , Graft vs Host Disease/drug therapy , Mice , Mice, Inbred C57BL , Nitriles , Programmed Cell Death 1 Receptor , Pyrazoles , Pyrimidines , Transplantation, Homologous
4.
Eur J Nucl Med Mol Imaging ; 48(2): 361-371, 2021 02.
Article in English | MEDLINE | ID: mdl-32794105

ABSTRACT

PURPOSE: This study aimed to investigate the deep learning model (DLM) combining computed tomography (CT) images and clinicopathological information for predicting anaplastic lymphoma kinase (ALK) fusion status in non-small cell lung cancer (NSCLC) patients. MATERIALS AND METHODS: Preoperative CT images, clinicopathological information as well as the ALK fusion status from 937 patients in three hospitals were retrospectively collected to train and validate the DLM for the prediction of ALK fusion status in tumors. Another cohort of patients (n = 91) received ALK tyrosine kinase inhibitor (TKI) treatment was also included to evaluate the value of the DLM in predicting the clinical outcomes of the patients. RESULTS: The performances of the DLM trained only by CT images in the primary and validation cohorts were AUC = 0.8046 (95% CI 0.7715-0.8378) and AUC = 0.7754 (95% CI 0.7199-0.8310), respectively, while the DLM trained by both CT images and clinicopathological information exhibited better performance for the prediction of ALK fusion status (AUC = 0.8540, 95% CI 0.8257-0.8823 in the primary cohort, p < 0.001; AUC = 0.8481, 95% CI 0.8036-0.8926 in the validation cohort, p < 0.001). In addition, the deep learning scores of the DLMs showed significant differences between the wild-type and ALK infusion tumors. In the ALK-target therapy cohort (n = 91), the patients predicted as ALK-positive by the DLM showed better performance of progression-free survival than the patients predicted as ALK-negative (16.8 vs. 7.5 months, p = 0.010). CONCLUSION: Our findings showed that the DLM trained by both CT images and clinicopathological information could effectively predict the ALK fusion status and treatment responses of patients. For the small size of the ALK-target therapy cohort, larger data sets would be collected to further validate the performance of the model for predicting the response to ALK-TKI treatment.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Deep Learning , Lung Neoplasms , Anaplastic Lymphoma Kinase/genetics , Carcinoma, Non-Small-Cell Lung/diagnostic imaging , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/genetics , Humans , Lung Neoplasms/diagnostic imaging , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Protein Kinase Inhibitors/therapeutic use , Retrospective Studies , Tomography, X-Ray Computed
5.
Macromol Rapid Commun ; 42(7): e2000661, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33480461

ABSTRACT

The synthesis of thermo-responsive polymers from non-responsive and water-soluble monomers has great practical advantages but significant challenges. Herein, the authors report a novel aqueous copolymerization strategy to prepare polymers with tunable upper critical solution temperature (UCST) or lower critical solution temperature (LCST) from non-responsive monomers. Acrylic acid (AAc), N-vinylpyrrolidone (NVP), and acrylamide (AAm) are copolymerized in water, yielding copolymers with UCST behavior. Interestingly, by simply replacing AAm with its methylated homologue, dimethyl acrylamide (DMA), the thermo-responsiveness of the copolymers is converted into LCST-type. The cloud points of the copolymers can be tuned rationally with their monomer ratios and the condition of the solvent. The UCST property of the poly(AAc-NVP-AAm) comes from the AAc-AAm and AAc-NVP hydrogen-bonds, while the LCST property of poly(AAc-NVP-DMA) originates from the hydrophobic aggregation of AAc-NVP complex and DMA, as indicated by temperature-dependent 1 H NMR and dynamic light scattering.


Subject(s)
Hydrogen , Polymers , Polymerization , Temperature , Water
6.
Microsc Microanal ; 26(1): 148-156, 2020 02.
Article in English | MEDLINE | ID: mdl-31753050

ABSTRACT

The seminiferous tubule (ST) is the location of spermatogenesis, where mature spermatozoa are produced with the assistance of Sertoli cells. The role of extracellular vesicles in the direct communication between Sertoli-germ cells in the ST is still not fully understood. In this study, we reported multivesicular bodies (MVBs) and their source of CD63-enriched exosomes by light and ultrastructure microscopy during the reproductive phases of turtles. Strong CD63 immunopositivity was detected at the basal region in the early and luminal regions of the ST during late spermatogenesis by immunohistochemistry (IHC), immunofluorescence (IF), and western blot (WB) analysis. Labeling of CD63 was detected in the Sertoli cell cytoplasmic processes that surround the developing germ cells during early spermatogenesis and in the lumen of the ST with elongated spermatids during late spermatogenesis. Furthermore, ultrastructure analysis confirmed the existence of numerous MVBs in the Sertoli cell prolongations that surround the round and primary spermatogonia during acrosome biogenesis and with the embedded heads of spermatids in the cytoplasm of Sertoli cells. Additionally, in spermatids, Chrysanthemum flower centers (CFCs) generated isolated membranes involved in MVBs and autophagosome formation, and their fusion to form amphiosomes was also observed. Additionally, autophagy inhibition by 3-methyladenine (after 24 h) increased CD63 protein signals during late spermatogenesis, as detected by IF and WB. Collectively, our study found MVBs and CD63 rich exosomes within the Sertoli cells and their response to autophagy inhibition in the ST during the spermatogenesis in the turtle.


Subject(s)
Exosomes/ultrastructure , Multivesicular Bodies/ultrastructure , Seminiferous Tubules/physiology , Seminiferous Tubules/ultrastructure , Spermatogenesis , Tetraspanin 30/analysis , Turtles/physiology , Animals , Blotting, Western , Exosomes/chemistry , Immunohistochemistry , Male , Microscopy, Electron , Microscopy, Fluorescence , Multivesicular Bodies/chemistry
7.
Biol Blood Marrow Transplant ; 25(10): 1911-1919, 2019 10.
Article in English | MEDLINE | ID: mdl-31195136

ABSTRACT

High-dose chemotherapy and/or radiation given before an allogeneic hematopoietic cell transplantation severely damage thymic epithelial cells (TECs), resulting in poor post-transplant immune recovery. IL-22 mediates recovery of TECs via a proregenerative effect, but the precise mechanism by which this occurs is unknown. In this study, we found IL-22 improved thymus recovery after damage from irradiation in association with increased number of TECs. This effect was blocked by ruxolitinib, a JAK1/JAK2 inhibitor. IL-22 increased the number of TECs via a Stat3-dependent signaling in the mTEC1 murine thymic epithelial cell line. This, in turn, upregulated transcription of myeloid cell leukemia sequence 1 (Mcl1), resulting in increased number of TECs. Similar effects were seen in irradiated mice given IL-22. Defects in IL-22 resulted in delayed thymus recovery in irradiated mice and had an impact on levels of thymus function-related genes such as Foxn1, Aire, and Kgf. In mice, post-transplant use of IL-22 improved repair of TECs, increased the numbers of thymus T cells, increased the intrathymic levels of Aire, and increased the proportion of natural regulatory T cells, resulting in decreased severity of chronic graft-versus-host disease (GVHD). Our data highlight the critical role of the IL-22/Stat3/Mcl-1 pathway in the regeneration of TECs after damage from irradiation in mice and highlight circumstances where normalizing thymus T cell function with IL-22 decreases GVHD after allotransplants.


Subject(s)
Graft vs Host Disease/prevention & control , Interleukins/therapeutic use , STAT3 Transcription Factor/metabolism , Thymus Gland/growth & development , Transplantation, Homologous/methods , Animals , Cell Line , Chronic Disease , Disease Models, Animal , Humans , Mice , Interleukin-22
8.
Reprod Biol Endocrinol ; 17(1): 19, 2019 Feb 09.
Article in English | MEDLINE | ID: mdl-30738428

ABSTRACT

BACKGROUND: Steroidogenesis is an indispensable process that is indirectly associated with spermatogenesis in the Leydig cell (LC) to utilize the lipid droplets (LDs) that are critical to maintaining normal testosterone synthesis. The regulation of LD mobilization, known as lipophagy, in the LC is still largely unknown. METHOD: In the present study, the LC of the Chinese soft-shelled turtle was investigated to identify the steroidogenic activity and lipophagy during the annual reproductive cycle by light microscopy, immunohistochemistry (IHC), immunofluorescence (IF), and transmission electron microscopy (TEM). RESULTS: The LC showed a dynamic steroidogenic function with strong activity of 3ß-HSD, vimentin and tubular ER during hibernation by IHC and TEM. The tubulo-vesicular ER had a weak immunopositive reaction for 3ß-HSD in the LC during reproductive phase, suggesting persistent steroidogenic activity. ORO staining and TEM demonstrated that a larger number of LDs had accumulated in the LC during hibernation than in the reproductive phase. These LDs existed in close association with mitochondria and lysosomes by being dynamically surrounded by intermediate filaments to facilitate LD utilization. Lysosomes were found directly attached to large LDs, forming an autophagic tube and engulfing LDs, suggesting that micro-lipophagy occurs during hibernation. Furthermore, the IHC of ATG7 (Autophagy Related Gene 7) and the IF of the LC3 (Microtubule-associated protein light chain 3), p62 (Sequestosome-1 (SQSTM1) and LAMP1(Lysosomal-associated membrane protein 1) results demonstrated strong expression, and further confirmation by TEM showed the existence of an autophagosome and an autolysosome and their fusion during the hibernation season. CONCLUSION: In conclusion, the present study provides clear evidence of LD consumption in the LC by lipophagy, lysosome and mitochondria during the hibernation period, which is a key aspect of steroidogenesis in the Chinese soft-shelled turtle.


Subject(s)
Autophagy/physiology , Leydig Cells/metabolism , Lipid Metabolism , Steroids/metabolism , Turtles/metabolism , Animals , Autophagosomes/metabolism , Autophagosomes/ultrastructure , Hibernation/physiology , Leydig Cells/ultrastructure , Lipid Droplets/metabolism , Lipid Droplets/ultrastructure , Lysosomes/metabolism , Lysosomes/ultrastructure , Male , Microscopy, Electron, Transmission , Microscopy, Fluorescence , Mitochondria/metabolism , Mitochondria/ultrastructure , Reproduction/physiology , Turtles/physiology
9.
J Transl Med ; 16(1): 311, 2018 11 15.
Article in English | MEDLINE | ID: mdl-30442147

ABSTRACT

BACKGROUND: Platycodin D (PD) is one of the major bioactive components of the roots of Platycodon grandiflorum and possesses multiple biological and pharmacological properties, such as antiviral, anti-inflammatory, and anti-cancer activities. However, whether it affects platelet function remains unclear. This study aims to evaluate the role of PD in platelet function and thrombus formation. METHODS: Platelets were treated with PD followed by measuring platelet aggregation, activation, spreading, clot retraction, expression of glycoprotein receptors. Moreover, mice platelets were treated with PD and infused into wild-type mice for analysis of in vivo hemostasis and arterial thrombosis. RESULTS: Platycodin D treatment significantly inhibited platelet aggregation in response to collagen, ADP, arachidonic acid and epinephrine, reduced platelet P-selectin expression, integrin αIIbß3 activation, spreading on fibrinogen as well as clot retraction, accompanied with decreased phosphorylation of Syk and PLCγ2 in collagen-related peptide or thrombin-stimulated platelets. Moreover, PD-treated mice platelets presented significantly impaired in vivo hemostasis and arterial thrombus formation. Interestingly, PD induced internalization of glycoprotein receptors αIIbß3, GPIbα and GPVI. However, GM6001, cytochalasin D, BAPTA-AM and wortmannin did not prevent PD-induced internalization of receptors. CONCLUSIONS: Our study demonstrates that PD inhibits platelet aggregation, activation and impairs hemostasis and arterial thrombosis, suggesting it might be a potent anti-thrombotic drug.


Subject(s)
Blood Platelets/metabolism , Blood Platelets/pathology , Endocytosis/drug effects , Platelet Membrane Glycoproteins/metabolism , Saponins/pharmacology , Thrombosis/pathology , Triterpenes/pharmacology , Animals , Apoptosis/drug effects , Arteries/drug effects , Arteries/pathology , Blood Platelets/drug effects , Clot Retraction/drug effects , Hemostasis/drug effects , Humans , Mice, Inbred C57BL , P-Selectin/metabolism , Phospholipase C gamma/metabolism , Phosphorylation/drug effects , Platelet Aggregation/drug effects , Signal Transduction/drug effects , Syk Kinase/metabolism
10.
Haematologica ; 103(9): 1568-1576, 2018 09.
Article in English | MEDLINE | ID: mdl-29794149

ABSTRACT

In addition to their hemostatic function, platelets play an important role in regulating the inflammatory response. The platelet NLRP3 inflammasome not only promotes interleukin-1ß secretion, but was also found to be upregulated during platelet activation and thrombus formation in vitro However, the role of NLRP3 in platelet function and thrombus formation in vivo remains unclear. In this study, we aimed to investigate the role of NLRP3 in platelet integrin αIIbß3 signaling transduction. Using NLRP3-/- mice, we showed that NLRP3-deficient platelets do not have significant differences in expression of the platelet-specific adhesive receptors αIIbß3 integrin, GPIba or GPVI; however, NLRP3-/- platelets transfused into wild-type mice resulted in prolonged tail-bleeding time and delayed arterial thrombus formation, as well as exhibiting impaired spreading on immobilized fibrinogen and defective clot retraction, concomitant with decreased phosphorylation of c-Src, Syk and PLCγ2 in response to thrombin stimulation. Interestingly, addition of exogenous recombinant interleukin-1ß reversed the defect in NLRP3-/- platelet spreading and clot retraction, and restored thrombin-induced phosphorylation of c-Src/Syk/PLCγ2, whereas an anti-interleukin-1ß antibody blocked spreading and clot retraction mediated by wild-type platelets. Using the direct NLRP3 inhibitor, CY-09, we demonstrated significantly reduced human platelet aggregation in response to threshold concentrations of collagen and ADP, as well as impaired clot retraction in CY-09-treated human platelets, supporting a role for NLRP3 also in regulating human platelet αIIbß3 outside-in signaling. This study identifies a novel role for NLRP3 and interleukin-1ß in platelet function, and provides a new potential link between thrombosis and inflammation, suggesting that therapies targeting NLRP3 or interleukin-1ß might be beneficial for treating inflammation-associated thrombosis.


Subject(s)
Blood Platelets/metabolism , Hemostasis , NLR Family, Pyrin Domain-Containing 3 Protein/genetics , Platelet Glycoprotein GPIIb-IIIa Complex/metabolism , Signal Transduction , Thrombosis/etiology , Thrombosis/metabolism , Animals , Biomarkers , Blood Coagulation/genetics , Cell Degranulation , Clot Retraction , Disease Models, Animal , Gene Expression , Humans , Mice , Mice, Knockout , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Platelet Activation , Platelet Aggregation/genetics , Platelet Function Tests , Thrombosis/pathology
11.
Thromb Haemost ; 124(7): 641-648, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38151026

ABSTRACT

BACKGROUND: Transforming growth factor-ß1 (TGF-ß1) modulates multiple cellular functions during development and tissue homeostasis. A large amount of TGF-ß1 is stored in platelet α-granules and released upon platelet activation. Whether platelet-derived TGF-ß1 plays a role in venous thrombosis remains unclear. This study intends to assess the role of platelet-derived TGF-ß1 in the development of venous thrombosis in mice. MATERIAL AND METHODS: TGF-ß1flox/flox and platelet-specific TGF-ß1-/- mice were utilized to assess platelet function in vitro, arterial thrombosis induced by FeCl3, tail bleeding time, prothrombin time (PT), activated partial thromboplastin time (APTT), and deep vein thrombosis induced through ligation of the inferior vena cava (IVC). The IVC sample was collected to measure accumulation of neutrophils, monocytes, and the formation of neutrophil extracellular traps (NETs) by immunofluorescence staining. RESULTS: TGF-ß1 deficiency in platelets did not affect the number of circulating platelets, platelet aggregation, adenosine triphosphate release, and integrin αIIbß3 activation. Meanwhile, TGF-ß1 deficiency did not alter the arterial thrombus formation, hemostasis, and coagulation time (PT and APTT), but significantly impaired venous thrombus formation, inhibited the recruitment and accumulation of neutrophils and monocytes in thrombi, as well as reduced formation of NETs and platelet-neutrophil complex. In addition, adoptive transfer of TGF-ß1flox/flox platelets to TGF-ß1-/- mice rescued the impaired venous thrombus formation, recruitment of leukocytes and monocytes, as well as the NETs formation. CONCLUSION: In conclusion, platelet-derived TGF-ß1 positively modulates venous thrombus formation in mice, indicating that targeting TGF-ß1 might be a novel approach for treating venous thrombosis without increasing the risk of bleeding.


Subject(s)
Blood Platelets , Mice, Knockout , Transforming Growth Factor beta1 , Venous Thrombosis , Animals , Venous Thrombosis/blood , Venous Thrombosis/metabolism , Transforming Growth Factor beta1/metabolism , Blood Platelets/metabolism , Mice , Disease Models, Animal , Mice, Inbred C57BL , Platelet Activation , Blood Coagulation , Platelet Aggregation , Extracellular Traps/metabolism , Male , Neutrophils/metabolism , Vena Cava, Inferior/pathology , Vena Cava, Inferior/metabolism , Hemostasis
12.
J Affect Disord ; 329: 81-87, 2023 05 15.
Article in English | MEDLINE | ID: mdl-36841301

ABSTRACT

BACKGROUND: Hopelessness is closely related to depression, trauma, and some organic diseases. Yet our understanding of the heterogeneity of hopelessness is limited. This study aimed to explore the heterogeneity of hopelessness, how it corresponds to the severity of depression, and the effect of traumatic experiences on it during COVID-19. METHOD: The current study measures 28,360 Chinese college students (67.4 % of women) with the Beck Hopelessness Scale (BHS), Trauma Experience Questionnaire, and Patient Health Questionnaire-9 (PHQ-9). The method of latent class analysis (LCA) was used to identify different sub-groups of hopelessness with differences in emotion, motivation, and cognition. Logistic regression and analysis of variance were used to determine the characteristics of different sub-groups. RESULTS: Three latent classes were identified: Negative affective cognition class (C1, N = 5940, 20.9 %), Negative thought cognition class (C2, N = 1358, 4.8 %), and Low hopelessness class (C3, N = 21,062, 74.3 %). Gender, only child or not, birthplace, family economic status, and grade are predictors of the latent category of hopelessness. There are significant differences in depression among different latent classes, and C1 > C2 > C3 (p < 0.001). Traumatic experience is a risk factor for the hopeless latent classes (OR > 1, P < 0.001). LIMITATIONS: Research findings may not be applied to other populations and rely on subjective reports. Ignore the effects of other protective and risk factors. Lack of longitudinal research, unable to explore causality. CONCLUSIONS: The current study provides evidence for the heterogeneity of hopelessness and informs targeted interventions for mental health problems (hopelessness) in college students.


Subject(s)
COVID-19 , Depression , Child , Humans , Female , Depression/epidemiology , Depression/psychology , Latent Class Analysis , Pandemics , Emotions
13.
Sheng Wu Gong Cheng Xue Bao ; 39(3): 1202-1216, 2023 Mar 25.
Article in Zh | MEDLINE | ID: mdl-36994582

ABSTRACT

Biodegradation of pyridine pollutant by microorganisms is one of the economical and effective methods to solve the environmental pollution of pyridine under high salinity conditions. To this end, screening of microorganisms with pyridine degradation capability and high salinity tolerance is an important prerequisite. In this paper, a salt-resistant pyridine degradation bacterium was isolated from the activated sludge of Shanxi coking wastewater treatment plant, and identified as a bacterium belonging to Rhodococcus on the basis of colony morphology and 16S rDNA gene phylogenetic analysis. Salt tolerance experiment showed that strain LV4 could grow and degrade pyridine with the initial concentration of 500 mg/L completely in 0%-6% saline environment. However, when the salinity was higher than 4%, strain LV4 grew slowly and the degradation time of pyridine by strain LV4 was significantly prolonged. Scanning electron microscopy showed that the cell division of strain LV4 became slower, and more granular extracellular polymeric substance (EPS) was induced to secrete in high salinity environment. When the salinity was not higher than 4%, strain LV4 responded to the high salinity environment mainly through increasing the protein content in EPS. The optimum conditions for pyridine degradation by strain LV4 at 4% salinity were 30 ℃, pH 7.0 and 120 r/min (DO 10.30 mg/L). Under these optimal conditions, strain LV4 could completely degrade pyridine with an initial concentration of 500 mg/L at a maximum rate of (29.10±0.18) mg/(L·h) after 12 h adaptation period, and the total organic carbon (TOC) removal efficiency reached 88.36%, indicating that stain LV4 has a good mineralization effect on pyridine. By analyzing the intermediate products in pyridine degradation process, it was speculated that strain LV4 achieved pyridine ring opening and degradation mainly through two metabolic pathways: pyridine-ring hydroxylation and pyridine-ring hydrogenation. The rapid degradation of pyridine by strain LV4 in high salinity environment indicates its application potential in the pollution control of high salinity pyridine environment.


Subject(s)
Rhodococcus , Rhodococcus/genetics , Phylogeny , Extracellular Polymeric Substance Matrix/metabolism , Sewage , Biodegradation, Environmental , Pyridines/metabolism
14.
ACS Omega ; 8(30): 27429-27438, 2023 Aug 01.
Article in English | MEDLINE | ID: mdl-37546650

ABSTRACT

In the flotation process, the frother, which is typically a surfactant, can be added to the pulp to reduce the surface tension and create stable foam. Currently, the nonionic mixed surfactant is widely employed as the frother for fine coal flotation. In this study, we focused on examining the foam properties of a mixed surfactant comprising short-chain methyl isobutyl carbinol (MIBC) and long-chain polyethylene glycol-1000 (PEG). Analytical techniques such as surface tension measurement, dynamic foam stability measurement, bubble morphology observation, and foam film drainage measurement were used to investigate the foam properties in single and mixed surfactant solution from a macroscopic scale to a microscopic scale. The surface tension results indicated that PEG exhibited higher surface activity than MIBC, and the addition of PEG to MIBC resulted in a significant reduction in solution surface tension. The dynamic foam stability analysis revealed that the incorporation of a small amount of PEG into MIBC solution notably improved foam stability. Furthermore, the addition of PEG to the MIBC solution led to a shift in the bubble size distribution curve from a "double peak" to a "single peak" shape. This shift indicated a substantial reduction in bubble size, indicating an enhanced inhibition of bubble coalescence. Additionally, the liquid film drainage rate was significantly slowed down, and the stability of the liquid film was improved upon the addition of PEG to MIBC. This improvement can be attributed to the synergistic effect of MIBC and PEG molecules adsorbed at the gas-liquid interface. The synergistic effect of mixed MIBC-PEG was due to the additional surface tension gradient created by the difference in surface activity between PEG and MIBC. This surface tension gradient enhances the Marangoni flow of surfactant molecules, thereby improving the self-healing ability of the liquid film and increasing its stability.

15.
ACS Omega ; 8(17): 15479-15487, 2023 May 02.
Article in English | MEDLINE | ID: mdl-37151510

ABSTRACT

Efficient flotation of low-rank coal is of great significance for the development of green and low-carbon cycles. Temperature is a crucial parameter of flotation, but the mechanism of its effect on flotation lacks understanding. In this paper, the mechanism was studied by kinetic flotation, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, low-temperature liquid-nitrogen adsorption (LP-N2A), X-ray photoelectron spectroscopy (XPS), and molecular dynamics simulation. The flotation combustible recovery gradually decreases as temperature rises. Compared with 60 °C, the combustible recovery at 5 °C increases by 18.13%. The desorption energy for oil droplets decreases as the temperature rises. As a result, the oil droplets are easier to desorb at high temperatures. The SEM and LP-N2A results demonstrate that the pores and fractures of the coal sample are well developed. Also, the oil-water interfacial tension and viscosity of oil droplets decrease as the temperature rises, while the diffusion ability increases. These increase the volume of oil droplets that penetrate into the pores, resulting in poor spreadability of oil droplets on the coal surface. The average volume of bubbles gradually increases as temperature rises, which renders the flotation foam unstable and worsens the flotation. Therefore, the flotation performance is better at low temperatures.

16.
Cyborg Bionic Syst ; 4: 0053, 2023.
Article in English | MEDLINE | ID: mdl-37766796

ABSTRACT

Biomachine hybrid robots have been proposed for important scenarios, such as wilderness rescue, ecological monitoring, and hazardous area surveying. The energy supply unit used to power the control backpack carried by these robots determines their future development and practical application. Current energy supply devices for control backpacks are mainly chemical batteries. To achieve self-powered devices, researchers have developed solar energy, bioenergy, biothermal energy, and biovibration energy harvesters. This review provides an overview of research in the development of chemical batteries and self-powered devices for biomachine hybrid robots. Various batteries for different biocarriers and the entry points for the design of self-powered devices are outlined in detail. Finally, an overview of the future challenges and possible directions for the development of energy supply devices used to biomachine hybrid robots is provided.

17.
Nat Commun ; 14(1): 4829, 2023 08 10.
Article in English | MEDLINE | ID: mdl-37563135

ABSTRACT

Human MutT Homolog 1 (MTH1) is a nucleotide pool sanitization enzyme that hydrolyzes oxidized nucleotides to prevent their mis-incorporation into DNA under oxidative stress. Expression and functional roles of MTH1 in platelets are not known. Here, we show MTH1 expression in platelets and its deficiency impairs hemostasis and arterial/venous thrombosis in vivo. MTH1 deficiency reduced platelet aggregation, phosphatidylserine exposure and calcium mobilization induced by thrombin but not by collagen-related peptide (CRP) along with decreased mitochondrial ATP production. Thrombin but not CRP induced Ca2+-dependent mitochondria reactive oxygen species generation. Mechanistically, MTH1 deficiency caused mitochondrial DNA oxidative damage and reduced the expression of cytochrome c oxidase 1. Furthermore, MTH1 exerts a similar role in human platelet function. Our study suggests that MTH1 exerts a protective function against oxidative stress in platelets and indicates that MTH1 could be a potential therapeutic target for the prevention of thrombotic diseases.


Subject(s)
Blood Platelets , Thrombosis , Humans , Blood Platelets/metabolism , Phosphoric Monoester Hydrolases/metabolism , Thrombin/pharmacology , Thrombin/metabolism , Oxidative Stress , Hemostasis , Nucleotides/metabolism , Mitochondria/metabolism , Thrombosis/genetics , Thrombosis/prevention & control , DNA Repair Enzymes/genetics , DNA Repair Enzymes/metabolism
18.
Int J Biol Macromol ; 229: 247-259, 2023 Feb 28.
Article in English | MEDLINE | ID: mdl-36529225

ABSTRACT

Risk-stratification of acute myeloid leukemia (AML) based on (cyto)genetic aberrations, including hotspot mutations, deletions and point mutations have evolved substantially in recent years. With the development of next-generation sequence technology, more and more novel mutations in the AML were identified. Thus, to unravel roles and mechanism of novel mutations would improve prognostic and predictive abilities. In this study, two novel germline JAK2 His608Tyr (H608Y) and His608Asn (H608N) mutations were identified and the molecular basis of these mutations in the leukemiagenesis of AML was elucidated. Our results indicated that JAK2 H608Y and H608N mutations disrupted the hydrogen bond between Q656 and H608 which reduced the JH2 domain's activity and abolished interactions between JH1 and JH2 domains, forced JAK2 into the active conformation, facilitated the entrance of substrates and thus caused JAK2 hyperactivation. Further studies suggested that JAK2 H608Y and H608N mutations enhanced the cell proliferation and inhibited the differentiation of Ba/F3 and MV4-11 cells via activating the JAK2-STAT5 signaling pathway. Moreover, rescue experiments demonstrated that mutations repaired the hydrogen bond between Q656 and H608 displayed opposite results. Thus, this study revealed the molecular basis of JAK2 H608Y and H608N mutations in the pathology of AML.


Subject(s)
Janus Kinase 2 , Leukemia, Myeloid, Acute , Humans , Janus Kinase 2/metabolism , Mutation , Leukemia, Myeloid, Acute/genetics , Leukemia, Myeloid, Acute/pathology , Cell Proliferation/genetics , Signal Transduction/genetics , Cell Differentiation
19.
Thromb Haemost ; 123(2): 207-218, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36252813

ABSTRACT

Intracellular cyclic GMP (cGMP) inhibits platelet function. Platelet cGMP levels are controlled by phosphodiesterase 5A (PDE5A)-mediated degradation. However, the exact role of PDE5A in platelet function and thrombus formation remains poorly understood. In this study, we characterized the role of PDE5A in platelet activation and function. Platelets were isolated from wild type or PDE5A-/- mice to measure platelet aggregation, activation, phosphatidylserine exposure (annexin-V binding), reactive oxygen species (ROS) generation, platelet spreading as well as clot retraction. Cytosolic calcium mobilization was measured using Fluo-4 AM by a microplate reader. Western blot was used to measure the phosphorylation of VASP, ERK1/2, p38, JNK, and AKT. FeCl3-induced arterial thrombosis and venous thrombosis were assessed to evaluate the in vivo hemostatic function and thrombus formation. Additionally, in vitro thrombus formation was assessed in a microfluidic whole-blood perfusion assay. PDE5A-deficient mice presented significantly prolonged tail bleeding time and delayed arterial and venous thrombus formation. PDE5A deficiency significantly inhibited platelet aggregation, ATP release, P-selectin expression, and integrin aIIbb3 activation. In addition, an impaired spreading on collagen or fibrinogen and clot retraction was observed in PDE5A-deficient platelets. Moreover, PDE5A deficiency reduced phosphatidylserine exposure, calcium mobilization, ROS production, and increased intracellular cGMP level along with elevated VASP phosphorylation and reduced phosphorylation of ERK1/2, p38, JNK, and AKT. In conclusion, PDE5A modulates platelet activation and function and thrombus formation, indicating that therapeutically targeting it might be beneficial for the treatment of thrombotic diseases.


Subject(s)
Proto-Oncogene Proteins c-akt , Thrombosis , Mice , Animals , Cyclic Nucleotide Phosphodiesterases, Type 5/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Calcium/metabolism , Phosphatidylserines/metabolism , Reactive Oxygen Species/metabolism , Platelet Aggregation , Platelet Activation , Blood Platelets/metabolism , Phosphorylation , Cyclic GMP/metabolism
20.
Int Immunopharmacol ; 120: 110381, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37245302

ABSTRACT

BACKGROUND: Dimethyl fumarate (DMF) is a methyl ester of fumaric acid and has been approved for treating multiple sclerosis (MS) and psoriasis due to anti-inflammatory effect. There is a close association between platelets and the pathogenesis of MS. Whether DMF affects platelet function remains unclear. Our study intends to evaluate DMF's effect on platelet function. METHODS: Washed human platelets were treated with different concentrations of DMF (0, 50, 100 and 200 µM) at 37 °C for 1 h followed by analysis of platelet aggregation, granules release, receptors expression, spreading and clot retraction. In addition, mice received intraperitoneal injection of DMF (15 mg/kg) to assess tail bleeding time, arterial and venous thrombosis. RESULTS: DMF significantly inhibited platelet aggregation and the release of dense/alpha granules in response to collagen-related peptide (CRP) or thrombin stimulation dose-dependently without altering the expression of platelet receptors αIIbß3, GPIbα, and GPVI. In addition, DMF-treated platelets presented significantly reduced spreading on collagen or fibrinogen and thrombin-mediated clot retraction along with the decreased phosphorylation of c-Src and PLCγ2. Moreover, administration of DMF into mice significantly prolonged the tail bleeding time and impaired arterial and venous thrombus formation. Furthermore, DMF reduced the generation of intracellular reactive oxygen species and calcium mobilization, and inhibited NF-κB activation and the phosphorylation of ERK1/2, p38 and AKT. CONCLUSION: DMF inhibits platelet function and arterial/venous thrombus formation. Considering the presence of thrombotic events in MS, our study indicates that DMF treatment for patients with MS might obtain both anti-inflammatory and anti-thrombotic benefits.


Subject(s)
Platelet Activation , Thrombosis , Humans , Mice , Animals , Fibrinolytic Agents , Dimethyl Fumarate/pharmacology , Dimethyl Fumarate/therapeutic use , Dimethyl Fumarate/metabolism , Thrombin/metabolism , Thrombin/pharmacology , Platelet Aggregation , Blood Platelets/metabolism , Thrombosis/drug therapy , Thrombosis/etiology , Thrombosis/metabolism
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