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1.
Appl Opt ; 61(34): 10072-10079, 2022 Dec 01.
Article in English | MEDLINE | ID: mdl-36606766

ABSTRACT

We propose an efficient scheme to manipulate the Goos-Hänchen (GH) shift of a reflected beam from a metal-clad waveguide, where a coherent atomic medium with a Λ-type configuration is employed as the substrate. Using experimentally achievable parameters, we identify the conditions under which spontaneously generated coherence (SGC) allows us to enhance the spatial and angular GH shifts of the reflected beam. With the help of SGC, the relative phases of the probe and control fields can alter the absorption gain and refractive index of the atomic medium, thereby manipulating the magnitudes, signs, and positions of the spatial and angular shifts. Furthermore, the spatial and angular GH shifts can be coherently controlled via adjusting the incoherent pumping rate and the intensity of the control field. Our proposal provides an avenue for the manipulation of spatial and angular GH shifts and potential applications in optical switching and optical steering.

2.
J Phycol ; 57(1): 335-344, 2021 02.
Article in English | MEDLINE | ID: mdl-33174223

ABSTRACT

To explore the species diversity and toxin profile of Pseudo-nitzschia, monoclonal strains were established from Chinese southeast coastal waters. The morphology was examined under light and transmission electron microscopy. The internal transcribed spacer region of ribosomal DNA was sequenced for phylogenetic analyses, and the secondary structure of ITS2 was predicted and compared among allied taxa. A combination of morphological and molecular data showed the presence of two new species, Pseudo-nitzschia hainanensis sp. nov. and Pseudo-nitzschia taiwanensis sp. nov. Pseudo-nitzschia hainanensis was characterized by a dumpy-lanceolate valve with slightly blunt apices and a central nodule, as well as striae comprising two rows of poroids. Pseudo-nitzschia taiwanensis was characterized by a slender-lanceolate valve, and striae comprising one row of split poroids. The poroid structure mainly comprised two sectors. Both taxa constituted their own monophyletic lineage in the phylogenetic analyses inferred from ITS2 rDNA and were well differentiated from other Pseudo-nitzschia species. Morphologically, P. hainanensis and P. taiwanensis could be assigned to the Pseudo-nitzschia delicatissima and the Pseudo-nitzschia pseudodelicatissima complex, respectively. Particulate domoic acid was measured using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS), but no detectable pDA was found. With the description of the two new species, the species diversity of genus Pseudo-nitzschia reaches 58 worldwide, among which 31 have been recorded from Chinese coastal waters.


Subject(s)
Diatoms , Tandem Mass Spectrometry , China , Chromatography, Liquid , Diatoms/genetics , Kainic Acid , Phylogeny
3.
Fish Shellfish Immunol ; 86: 280-286, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30448447

ABSTRACT

The present study was conducted to evaluate the protective effects of astaxanthin against lipopolysaccharide (LPS)-induced inflammatory responses in Channa argus in vivo and ex vivo. Primary hepatocytes were exposed to different concentrations of LPS for 24 h to induce an inflammatory response, and the protective effects of astaxanthin against LPS-induced inflammation were studied ex vivo and in vivo. Hepatocytes exposed to LPS (5-20 µg mL-1) alone for 24 h resulted in a significant increase in lactate dehydrogenase release (LDH), Nitric oxide (NO) production and Malondialdehyde (MDA) content, 10 µg mL-1 LPS could induced inflammatory response in hepatocytes. Gene expression of TLR4, NFkBp65, MAPKp38, TNF-α, IL-6 and IL-1ß mRNA expression were also enhanced ex vivo (p < 0.05). In vivo test demonstrated that pretreatment with astaxanthin prevented the LPS-induced upregulation of pro-inflammatory cytokines TNF-α, IL-6 and IL-1ß. Besides, astaxanthin blocked the expression of Toll-like receptor 4 (TLR4) and then suppressed the phosphorylation of nuclear transcription factor-kappa B (NF-κB) p65 and degradation inhibitor of NF-κBα (IκBα). Further study showed that astaxanthin could suppress the phosphorylation of p38, extracellular signal-regulated kinase (ERK) and c-jun NH2-terminal kinase (JNK) in mitogen-activated protein kinase (MAPK) signal pathway. In conclusion, our results suggest that astaxanthin played an anti-inflammatory role by regulating TLR4 and the NF-κB and MAPK signaling pathways in C. argus.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Fishes , Inflammation/chemically induced , MAP Kinase Signaling System/drug effects , NF-kappa B/drug effects , Animals , Cells, Cultured , Hepatocytes , Inflammation/drug therapy , Lipopolysaccharides/pharmacology , Signal Transduction , Xanthophylls/pharmacology
4.
Fish Shellfish Immunol ; 93: 1100-1110, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31422179

ABSTRACT

Nrf2/Keap1 pathway is associated with oxidative stress. l-carnitine is currently under preclinical evaluation as a antioxidant, but the use of l-carnitine in aquaculture has been poorly evaluated and so far no mechanism has been demonstrated. Here, we explored the effects of l-carnitine in vitro and in vivo and discussed the possible molecular mechanisms involved. Firstly, Nrf2-siRNA significantly knocked down the mRNA level of Nrf2 in FHM cells. Thus, the activities of antioxidant enzymes (T-SOD, CAT, GSH-PX) and the level of antioxidant substance (GSH) and the level of MDA showed that Nrf2-siRNA pretreatment weakened the protective effect of l-carnitine. Moreover, the mRNA levels of Keap1, Nrf2, Maf and HO-1 indicated that l-carnitine regulated Nrf2/Keap1 activation. Furthermore, oxidized fish oil remarkably suppressed growth in Rhynchocypris lagowski Dybowski, and the lower antioxidant capacity was also observed in liver. According to the results of immune related indexes (the levels of IL-1ß, TNF-α, LZM, AKP) in serum and the mRNA levels of immune related genes (NF-κB, IL-1ß, TNF-α, IL-8, IL-10 and TGF-ß) in liver, oxidized fish oil also induced inflammatory response in fish. Also, l-carnitine supplementation can relieve this bad condition. In conclusion, l-carnitine regulated Nrf2/Keap1 activation in vitro and in vivo and protected oxidized fish oil-induced inflammation response by inhibiting the NF-κB signaling pathway in Rhynchocypris lagowski Dybowski.


Subject(s)
Carnitine/metabolism , Cyprinidae/immunology , Fish Diseases/immunology , Fish Proteins/metabolism , Protective Agents/metabolism , Signal Transduction/drug effects , Animals , Anti-Inflammatory Agents/administration & dosage , Anti-Inflammatory Agents/pharmacology , Antioxidants/administration & dosage , Antioxidants/pharmacology , Carnitine/administration & dosage , Carrier Proteins/metabolism , Cell Line , Cyprinidae/genetics , Cyprinidae/growth & development , Dose-Response Relationship, Drug , Fish Diseases/drug therapy , Fish Oils/pharmacology , Inflammation/drug therapy , Inflammation/immunology , Inflammation/veterinary , NF-E2-Related Factor 2/metabolism , NF-kappa B/metabolism , Oxidation-Reduction , Oxidative Stress , Protective Agents/administration & dosage , Random Allocation
5.
Mol Biol Rep ; 46(2): 2221-2230, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30747383

ABSTRACT

The present study evaluated the effects of dietary Allium mongolicum Regel polysaccharide (AMRP) on growth, lipopolysaccharide-induced antioxidant responses and immune responses in Channa argus. A basal diet was supplemented with AMRP at 0, 1, 1.5 or 2 g/kg feed for 56 days. After the 56 days feeding period, weight gain (WG), specific growth rate (SGR) and feed conversion ratio (FCR) were significantly increased or decreased (P < 0.05) by dietary AMRP, with the highest WG, SGR and the minimum FCR occurring in 1.5 g/kg AMRP group. Furthermore, AMRP supplementation conferred significant protective effects against LPS challenge by preventing alterations in the levels of complements 3 (C3) and complements 4 (C4), lysozyme, superoxide dismutase (SOD), glutathione-S-transferase (GST), interleukin-1ß (IL-1ß) and tumour necrosis factor-α (TNF-α) while regulating the expression of immune-related genes including heat shock protein 70 (HSP70), heat shock protein 90 (HSP90), SOD, GST, IL-1 and TNF-α. Finally, AMRP supplementation significantly increased serum total protein, albumin and globulin concentrations and reduced mortality after LPS challenge. Taken together, our results suggest that the administration of AMRP could attenuate LPS-induced negative effects in C. argus, with 1.5 g/kg considered a suitable dose.


Subject(s)
Allium/metabolism , Fishes/metabolism , Plant Immunity/drug effects , Allium/physiology , Animal Feed , Animals , Antioxidants/metabolism , Antioxidants/physiology , Diet/methods , Dietary Supplements , Fishes/immunology , Immunity, Innate , Lipopolysaccharides/metabolism , Liver/metabolism , Polysaccharides/pharmacology
6.
Chin Med Sci J ; 32(4): 232-238, 2017 Dec 30.
Article in English | MEDLINE | ID: mdl-29301598

ABSTRACT

Objective The aim of this study was to investigate the relationship between peripheral plasma stem cell factor (SCF)/c-kit levels and the types of dipper and non-dipper hypertension in hypertensive patients. Methods This cross-sectional study included newly diagnosed hypertensive patients who underwent 24-hour ambulatory blood pressure monitor (ABPM) between January 2009 and 2012 in Jiangning city. Patients were divided into the dipper group and the non-dipper group according to ABPM measurements. The levels of SCF and its receptor c-kit, tumor necrosis factor-α (TNF-α) and interleukin 6 (IL-6) in peripheral blood were measured via enzyme-linked immunosorbent assays. The serum levels of glucose and lipid were examined as well. The levels of SCF/c-kit were compared between the dippers and the non-dippers; and their correlation with 24-hour mean systolic blood pressure (MSBP), 24-hour mean diastolic blood pressure (MDBP), TNF-α and IL-6 were investigated using linear regression analyses statistically. Results A total of 247 patients with newly diagnosed hypertension were recruited into the study, including 116 non-dippers and 131 dippers. The levels of peripheral plasma SCF were higher in non-dipper group (907.1±52.7 ng/L vs. 778.7±44.6 ng/L; t=2.837, P<0.01), and the levels of c-kit were higher in non-dipper group too (13.2±1.7 µg/L vs 9.57±1.4 µg/L; t=2.831, P<0.01). Linear regression analysis revealed that SCF/c-kit levels were significantly positively correlated with MSBP, MDBP, plasma TNF-α, and IL-6 levels (all P<0.01). Conclusions Peripheral plasma SCF/c-kit levels are higher in patients with non-dipper hypertension than those with dipper one, and significantly correlate with 24-hour MSBP, 24-hour MDBP, serum TNF-α and IL-6 levels.


Subject(s)
Blood Pressure , Hypertension/blood , Stem Cell Factor/blood , Adult , Aged , Female , Humans , Hypertension/physiopathology , Interleukin-6/blood , Male , Middle Aged , Tumor Necrosis Factor-alpha/blood
7.
Fish Physiol Biochem ; 43(4): 1081-1093, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28315160

ABSTRACT

Microcystin-LR (MCLR), one of the most popular microcystins (MCs) found in many field water bodies around the world, poses great health risks to animals and humans. In the present study, healthy common carp (initial weight 24.8 ± 2.3 g) were randomly assigned to five groups. Group I was fed on normal diet as control. Group II was maintained on normal diet and received MCLR intraperitoneal injection (150 µg kg-1 BW). Common carp in groups III, IV, and V were daily pretreated with L-carnitine (LC) at doses of 0.5, 1.0, and 2.0 g kg-1 of the diet for 4 weeks prior to MCLR intraperitoneal injection. The results showed that MCLR alone led to a significant downregulation in immune response, including serum complement C3, lysozyme, and bactericidal activity. However, oxidative stress response: catalase (CAT), superoxide dismutase (SOD), glutathione (GSH), glutathione peroxidase (GPx), and lipid peroxidation (LPO) levels were significantly increased. Similarly, gene expressions of inflammatory IL-1ß, TNF-α, IFN I, and heat shock proteins (HSP70 and HSP90) were also upregulated after challenged with MCLR. However, LC pretreated group caused a significant elevation in immune response (C3, lysozyme, and bactericidal activity) and gene expressions of inflammatory IL-1ß, TNF-α, IFN I, and heat shock proteins (HSP70 and HSP90) after MCLR stress. Antioxidant activities (CAT, SOD, GSH, GPx, and LPO) were returned to background levels at 96 h after MCLR challenge. Strikingly, LC supplementation at 2.0 g kg-1 has been considered the optimum for common carp since it exhibited enhancement of immune response and antioxidant activity over the level 0.5 and 1.0 g kg-1, and even better than that of control level. It was concluded that LC as a functional feed additive significantly inhibited the progression of MCLR-induced immunotoxicity and oxidative stress in common carp.


Subject(s)
Animal Feed/analysis , Carnitine/pharmacology , Carps/physiology , Microcystins/toxicity , Oxidative Stress/drug effects , Animal Nutritional Physiological Phenomena , Animals , Antioxidants/metabolism , Diet/veterinary , Enzymes/metabolism , Marine Toxins
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(1): 278-82, 2017 01.
Article in Zh | MEDLINE | ID: mdl-30221894

ABSTRACT

In this paper, a new method based on LASSO algorithm is studied for the estimation of stellar alpha element abundance. The information of alpha elements (O, Mg, Ca, Si, and Ti) of massive stars will help us to better understand the evolution of the galaxy. Presently the main method of determining the alpha element abundances from the low resolution spectra is the template matching method. However, it is difficult for us to optimize the algorithm parameters and the algorithm is sensitive to the noise. Thus, it is necessary to study the new method to determine the abundance. The experimental results show that the accuracy of LASSO algorithm on ELODIE spectra is 0.003 (0.078) dex. To explore the impact of the spectral resolution variation, we use ELODIE spectra to generate the spectral data sets with following resolutions: 42 000, 21 000, 10 500, 4 200 and 2 100 by using the Gaussian convolution. The results of the LASSO algorithm on these data sets are 0.003 3 (0.078) dex, -0.05 (0.059) dex, -0.007 (0.069) dex and -0.004 5 (0.067) dex, respectively. These results show that the LASSO algorithm is not sensitive to the change of the resolution. In order to verify the robustness of LASSO algorithm against the change of SNRs, we use ELODIE to generate the spectral data sets with following SNRs: 30, 25, 20, 15 and 5. The results of LASSO algorithm on the above data sets are: -0.002 (0.076) dex, -0.090 (0.073) dex, 0.003 6 (0.075) dex, 0.007 6 (0.078) dex and -0.009 (0.080) dex, respectively. Thus, LASSO algorithm is not sensitive to the change of SNR. Therefore, the LASSO algorithm is suitable for low resolution and low SNR spectra such as LAMOST and SDSS spectra. The accuracy of Lasso algorithm on the SDSS spectra is 0.003 7 (0.097) dex, and the results of LASSO on globular and open clusters show good agreement with literature values (within 1σ). Therefore, the LASSO algorithm can be used to estimate the alpha element abundances of stars.

9.
Fish Shellfish Immunol ; 51: 365-372, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26945938

ABSTRACT

The present study was conducted to evaluate the effects of different L-alanyl-l-glutamine (Ala-Gln) feeding strategies on the growth performance, metabolism and crowding stress resistance related parameters in juvenile Jian carp (Cyprinus carpio var. Jian) under crowded condition (80 g/L). Juvenile Jian carp (initial weight 26.1 ± 0.6 g) were distributed into five groups which fed with graded concentrations (0% or 1.0%) of Ala-Gln for eight weeks. Control group (I, 0/0) fed with control diet (0% Ala-Gln) throughout the feeding trial. The other four groups employed different control and experimental diet feeding strategies ranging from two weeks control diet fed and two weeks experimental diet (1% Ala-Gln) fed (II, 0/2) to eight weeks experimental diet fed (V, 4/4). Results revealed that Mean weight gain (MEG) under all different feeding strategies of Ala-Gln were significantly higher than that of the control group (p < 0.05), and MEG of group II (201.90%) was even higher than that of group IV (184.70%). Liver glycogen and blood total protein of groups II, III and V were significantly higher than that in groups I and IV (p < 0.05). The highest level of serum thyroxine (10.07 ng/ml), insulin-like growth factor-I (52.40 ng/ml) and insulin (9.73 µ IU/mL) were observed in group V. However, diet supplemented with Ala-Gln did not affect the levels of serum glucose, cortisol and catecholamine in fish. The mRNA expression of GR1a, GR1b and GR2 were also significantly changed in Ala-Gln supplementation groups compared with control group (p < 0.05). After fish intraperitoneally injected with virulent Aeromonas hydrophila, the fish survival rates were significantly increased in all Ala-Gln supplementation groups compared with control group (p < 0.05). Results from the present experiment showed the importance of dietary supplementation of Ala-Gln in benefaction of the growth performance, metabolism and crowding stress resistance in Jian carp breeding. The optimal feeding strategy was alternatively fed with control diet and then experimental diet at an interval of two weeks for juvenile Jian carp under crowded condition.


Subject(s)
Carps/physiology , Diet , Dipeptides/pharmacology , Animals , Aquaculture/methods , Blood Glucose/analysis , Catecholamines/blood , Crowding , Fish Proteins/genetics , Fish Proteins/metabolism , Glycogen/metabolism , HSP70 Heat-Shock Proteins/metabolism , Hydrocortisone/blood , Liver/drug effects , Liver/metabolism , RNA, Messenger/metabolism , Receptors, Glucocorticoid/genetics , Stress, Physiological
10.
Fish Shellfish Immunol ; 45(1): 124-31, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25703710

ABSTRACT

This study was undertaken to isolate active secondary metabolites from immunostimulatory Bacillus Licheniformis XY-52 and evaluate their activities at 0%, 0.5%, 1.0%, and 2.0% doses supplementation with feed on immune response in common carp at weeks 1, 2, and 3. By applying chromatography techniques and successive recrystallization, two purified metabolites were obtained and identified by spectral data (mass spectrometry and nuclear magnetic resonance) as: Cyclo-(Phe-Tyr) and Cyclo-(Phe-Gly). The results revealed that humoral innate immune parameters (lysozyme activity, phagocytic activity and bactericidal activity) were significantly (P < 0.05) increased after feeding on the two active compounds-supplemented diet. Furthermore, administration of the two active compounds significantly (P < 0.05) up regulated IL-1ß, Type 1 IFN, IFN g2b, IL10 and TNF-α gene expression. Heat shock protein 70 (HSP70) gene expression was significantly (P < 0.05) lower as compared to control group at the end of trial. Common carp fed with the two compounds had higher survival rates (69.3%) compared to the controls (32.0%) after challenged with the pathogen, Aeromonas hydrophila. The present study indicates that the two isolated active compounds could positively influence immune response and enhance disease resistance of common carp against A. hydrophila infection.


Subject(s)
Bacillus/chemistry , Carps , Fish Diseases/immunology , Gene Expression Regulation , Gram-Negative Bacterial Infections/veterinary , Immunity, Innate , Aeromonas hydrophila/physiology , Animal Feed/analysis , Animals , Chromatography, Gel/veterinary , Diet/veterinary , Dietary Supplements/analysis , Fish Diseases/genetics , Fish Diseases/microbiology , Fish Proteins/genetics , Fish Proteins/metabolism , Gram-Negative Bacterial Infections/genetics , Gram-Negative Bacterial Infections/immunology , Gram-Negative Bacterial Infections/microbiology , Immunity, Humoral
11.
Pest Manag Sci ; 79(7): 2539-2555, 2023 Jul.
Article in English | MEDLINE | ID: mdl-36864521

ABSTRACT

BACKGROUND: Natural products play a significant role in the development of novel bactericide candidates. Caesalpinia pulcherrima, a traditional medicine, had anti-inflammatory, antimicrobial, and antifeedant activities, therefore the previous bioassay results of C. pulcherrima implied that its main active ingredients may have potential to be used as botanical bactericides. RESULTS: Bio-guided isolation of C. pulcherrima was conducted to obtain 11 novel cassane diterpenoids (capulchemins A-K) and 10 known sesquiterpenes. Their structures were established by extensive spectroscopic methods and single-crystal X-ray diffraction analyses. Capulchemins A-F possess a rare aromatic C ring, while capulchemin K with a 15,16-degradative carbon skeleton represents a rare group of cassane diterpenes. Capulchemin A exhibited remarkable antibacterial activity against four phytopathogenic bacteria, particularly against Pseudomonas syringae pv. actinidae and Bacillus cereus, with minimal inhibitory concentration values of 3.13 µM. Meanwhile, capulchemin A showed significant control effect on kiwifruit canker in vivo. Further investigation of its mechanism of antibacterial activity revealed that compound 1 was closely related to destroy cell membrane to cause cell death. Additionally, some of those cassane diterpenoids showed potential antifeedant against Mythimna separate walker and Plutella xylostella. Consequently, capulchemin A could have the potential to be used as a template for the development for new eco-friendly NP-based bactericides. CONCLUSION: These data contribute to a better understanding of the antibacterial activity of cassane diterpenes. Cassane diterpenes have been discovered to be leading to broad application prospects in the development as novel botanical bactericides. © 2023 Society of Chemical Industry.


Subject(s)
Anti-Bacterial Agents , Caesalpinia , Diterpenes , Plant Extracts , Animals , Anti-Bacterial Agents/pharmacology , Caesalpinia/chemistry , Diterpenes/pharmacology , Diterpenes/chemistry , Microbial Sensitivity Tests , Molecular Structure , Moths , Seeds/chemistry , Plant Extracts/pharmacology
12.
Acta Psychol (Amst) ; 240: 104042, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37783184

ABSTRACT

Given that there is limited evidence concerning the psychometric properties of DASS-21 when applied to primary school students, the present study undertook a comprehensive exploration of the psychometric evidence supporting the use of the DASS-21 within this demographic. The research comprised three studies. In Study 1, the basic psychometric properties of internal consistency and construct validity were examined. A total of 3138 primary school students from three provinces in mainland China participated. The internal reliability of the overall scale was 0.93, and for all the subscales, it was higher than 0.80. Construct validity was partially supported. Both exploratory and confirmatory factor analyses upheld the factorial validity of the original three-factor structure. While convergent validity was established, the results showed unsatisfactory discriminant validity. The bifactor model showed that DASS-21 raw scores predominantly indicated the general factor, evidenced by the high explained common variance and omega-hierarchical values. However, the contributions from the three specific factors were minimal, with their omega hierarchical values all below 0.15. In Study 2, a longitudinal design was adopted, tracking 1366 primary school students from Southwest China over a three-month interval. The results further confirmed that the DASS-21 exhibited scalar time-invariance. The latent mean analysis showed that there were no statistically significant differences in the latent means of depression, anxiety, and stress between Time 1 and Time 2. In Study 3, which included 364 college students and 483 enterprise workers, the results demonstrated that the DASS-21 had measurement invariance across different populations. The latent mean analysis further confirmed that, in terms of the latent mean of all three subscales, both college students and enterprise workers had significantly higher scores than primary school students. Overall, the findings indicated that the DASS-21 is a suitable tool for screening schoolchildren for general psychological distress, but it is not suitable for discerning distinct negative mood state disorders.


Subject(s)
Anxiety , Depression , Psychiatric Status Rating Scales , Stress, Psychological , Child , Humans , Anxiety/diagnosis , Cross-Sectional Studies , Depression/diagnosis , East Asian People , Psychometrics , Reproducibility of Results , Stress, Psychological/diagnosis , Surveys and Questionnaires , Longitudinal Studies
13.
Front Psychol ; 13: 943449, 2022.
Article in English | MEDLINE | ID: mdl-36051193

ABSTRACT

Recent studies on the effects of mandatory online teaching, resulting from the COVID-19 pandemic, have widely reported low levels of satisfaction, unwillingness to continue online teaching, and negative impacts on the psychological well-being of teachers. Emerging research has highlighted the potential role of psychological need thwarting (PNT), in terms of autonomy, competence, and relatedness thwarting, resulting from online teaching. The aim of this study was to evaluate the immediate and delayed (longitudinal) effects of PNT of online teaching on teachers' well-being (including distress and burnout), intention to continue online teaching, and job satisfaction. Moreover, data collected from both cross-sectional and longitudinal surveys allowed for a systematic validation of an important instrument in the field of teacher psychology, the Psychological Need Thwarting Scale of Online Teaching (PNTSOT), in terms of longitudinal reliability and validity. The data reveal the usefulness of the construct of PNT in terms predicting and explaining teachers' willingness to continue using online teaching as well as the degree of burnout after a period of 2 months, such that PNT is positively associated with burnout and negatively associated with willingness to continue online teaching. As such, the PNTSOT is recommended for future research evaluating the long-term psychological, affective, and intentional outcomes stemming from teachers' PNT. Moreover, based on our findings that the impact from PNT of online teaching is persistent and long-term, we suggest that school leaders provide flexible and sustained professional development, model respectful and adaptive leadership, and create opportunities for mastery for the development of community of practice that can mitigate the thwarting of teachers' autonomy, competence, and relatedness during times of uncertainty. Additionally, in terms of the psychometric properties of the PNTSOT instrument, our empirical findings demonstrate internal reliability, test-retest reliability, measurement invariance, and criterion validity (concurrent and predictive) based on cross-sectional and longitudinal data.

14.
Phytochemistry ; 196: 113082, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35051786

ABSTRACT

Sixteen cassane diterpenoids (CAs), including four undescribed lactam-type, four unreported lactone-type, along with eight known ones, were isolated from the aerial parts of Caesalpinia pulcherrima (L.) Sw. Their structures were characterized by comprehensive spectroscopic analyses (including NMR and HRESIMS). The absolute configuration of pulcherritam A was finally established by single-crystal X-ray diffraction with Cu Kα radiation. Notably, pulcherritam s A-D were elucidated as a group of rare CAs bearing an α, ß-unsaturated γ-lactam ring rather than a typical lactone moiety. Almost all compounds were examined for their antibacterial. The results reveal that pulcherritam H exhibited significant antibacterial activities against Bacillus cereus, Staphylococcus aureus, as well as Pseudomonas syringae pv. actinidae (Psa) with the MIC from 6.25 to 12.5 µM, while pulcherritams A and C displayed potent antibacterial activities against methicillin-resistant Staphylococcus aureus (MRSA). Then, all isolates were evaluated for their anti-glioblastoma activities. Pulcherritam A and Pulcherrimin G illustrated moderate inhibitory activity against glioblastoma multiforme (GBM) U87MG cell, and the other compounds did not show obvious inhibitory activity against GBM U87MG cell. Furthermore, the preliminary structure-activity relationship and their biosynthetic pathway were also discussed.


Subject(s)
Caesalpinia , Diterpenes , Glioblastoma , Methicillin-Resistant Staphylococcus aureus , Anti-Bacterial Agents/pharmacology , Caesalpinia/chemistry , Diterpenes/chemistry , Molecular Structure , Plant Components, Aerial
15.
Nat Prod Res ; 36(18): 4636-4644, 2022 Sep.
Article in English | MEDLINE | ID: mdl-34842014

ABSTRACT

Three undescribed cassane-type diterpenoids (CAs), caesalpulcherrins K-M (1-3), together with three known ones (4-6) were isolated from the aerial parts of Caesalpinia pulcherrima (L.) Sw (Fabaceae). Their structures were elucidated via analysis of NMR (1 D and 2 D) and HRESIMS data. The character for caesalpulcherrin K possessing the olefin bond at C-11 and C-12 in its cassane skeleton was observed, which belonged to a small group among more than 450 CAs. That is, only fifteen derivatives have been reported up to now, to our knowledge. Biological evaluation revealed that compounds 1-6 exhibited moderate anti-inflammatory activity, with an IC50 value from 6.04 ± 0.34 to 8.92 ± 0.65 µM. Furthermore, compounds 5 and 6 exhibited significant α-glucosidase inhibitory activity at 10 µM.


Subject(s)
Caesalpinia , Diterpenes , Anti-Inflammatory Agents/analysis , Anti-Inflammatory Agents/pharmacology , Caesalpinia/chemistry , Diterpenes/chemistry , Glycoside Hydrolases , Molecular Structure , Seeds/chemistry
16.
Front Public Health ; 10: 987366, 2022.
Article in English | MEDLINE | ID: mdl-36407990

ABSTRACT

Background: To reduce the transmission of COVID-19, many teachers across the globe, including teachers in China, were required to teach online. This shift to online teaching can easily result in psychological need thwarting (PNT) of teachers' psychological basic needs (autonomy, competence, and relatedness), leaving them vulnerable to negative psychological outcomes. Resulting negative emotional state may lead to problematic internet use (PIU), which can lead to further psychological distress, forming a vicious cycle. Methods: The present study was conducted using a cross-lagged panel model (with longitudinal data) and hierarchical linear modeling (HLM) (with cross-sectional data). The aims were to investigate (i) the reciprocal relationships between two specific forms of PIU [problematic social media use (PSMU) and problematic gaming (PG)] and psychological distress among schoolteachers, and (ii) the influence of administrators' support on schoolteachers' PIU through a cross-level serial mediation model (PNT of online teaching was the first mediator and psychological distress was the second mediator affected by PNT of online teaching). Primary and secondary schoolteachers (N = 980; mean age = 34.76; 82.90% females) participated in two surveys (Time 1: mid-November 2021; Time 2: early-January 2022). Results: Results indicated that (i) high psychological distress at Time 1 was associated with increased levels of PSMU and PG at Time 2. Inversely, PG at Time 1 was associated with increased psychological distress at Time 2, although PSMU at Time 1 did not have a significant influence on psychological distress at Time 2; (ii) during Time 1, increased administrative support contributed to alleviating teachers' psychological needs thwarting of online teaching, thereby lowering their psychological distress which, in turn, resulted in a decrease in PG. Conclusion: PG had a stronger negative influence on teachers' psychological distress than PSMU. To relieve teachers' PG, administrative support can alleviate teachers' psychological needs thwarting of online teaching and psychological distress. Based on this finding, school managers must consider effective ways to support teachers during mandatory online teaching.


Subject(s)
COVID-19 , Psychological Distress , Humans , Female , Adult , Male , Internet Use , Cross-Sectional Studies , Schools
17.
Acta Pharmacol Sin ; 32(11): 1345-50, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21963897

ABSTRACT

AIM: To investigate the possible effects of telmisartan and losartan on cardiac function in adriamycin (ADR)-induced heart failure in rats, and to explore the changes in plasma level of angiotensin-(1-7)[Ang-(1-7)] and myocardial expression of angiotensin II type 1/2 receptors (AT(1)R / AT(2)R) and Mas receptor caused by the two drugs. METHODS: Male Sprague-Dawley rats were randomly divided into 4 groups: the control group, ADR-treated heart failure group (ADR-HF), telmisartan plus ADR-treated group (Tel+ADR) and losartan plus ADR-treated group (Los+ADR). ADR was administrated (2.5 mg/kg, ip, 6 times in 2 weeks). The rats in the Tel+ADR and Los+ADR groups were treated orally with telmisartan (10 mg/kg daily po) and losartan (30 mg/kg daily), respectively, for 6 weeks. The plasma level of Ang-(1-7) was determined using ELISA. The mRNA and protein expression of myocardial Mas receptor, AT(1)R and AT(2)R were measured using RT-PCR and Western blotting, respectively. RESULTS: ADR significantly reduced the plasma level of Ang-(1-7) and the expression of myocardial Mas receptor and myocardial AT(2)R, while significantly increased the expression of myocardial AT(1)R. Treatment with telmisartan and losartan effectively increased the plasma level of Ang-(1-7) and suppressed myocardial AT(1)R expression, but did not influence the expression of Mas receptor and AT(2)R. CONCLUSION: The protective effects of telmisartan and losartan in ADR-induced heart failure may be partially due to regulation of circulating Ang-(1-7) and myocardial AT(1)R expression.


Subject(s)
Angiotensin II Type 1 Receptor Blockers/therapeutic use , Angiotensin I/blood , Antibiotics, Antineoplastic/adverse effects , Benzimidazoles/therapeutic use , Benzoates/therapeutic use , Heart Failure/drug therapy , Losartan/therapeutic use , Peptide Fragments/blood , Receptor, Angiotensin, Type 1/genetics , Angiotensin I/metabolism , Angiotensin II Type 1 Receptor Blockers/pharmacology , Animals , Benzimidazoles/pharmacology , Benzoates/pharmacology , Doxorubicin/adverse effects , Gene Expression Regulation/drug effects , Heart/drug effects , Heart Failure/chemically induced , Losartan/pharmacology , Male , Myocardium/metabolism , Peptide Fragments/metabolism , Rats , Rats, Sprague-Dawley , Receptor, Angiotensin, Type 1/metabolism , Telmisartan
18.
Dalton Trans ; 50(46): 17129-17139, 2021 Nov 30.
Article in English | MEDLINE | ID: mdl-34779803

ABSTRACT

Ultrathin nanosheets of luminescent metal-organic frameworks or coordination polymers have been widely used for sensing ions, solvents and biomolecules but, as far as we are aware, not yet used for temperature sensing. Herein we report two luminescent uranyl phosphonates based on 2-(phosphonomethyl)benzoic acid (2-pmbH3), namely (UO2)(2-pmbH2)2 (1) and (H3O)[(UO2)2(2-pmb)(2-pmbH)] (2). The former has a supramolecular layer structure, composed of chains of corner-sharing {UO6} octahedra and {PO3C} tetrahedra which are connected by hydrogen bonds between phosphonate and carboxylic groups. Compound 2 possesses a unique 2D anionic framework structure, where the inorganic uranyl phosphonate chains made up of {UO7} and {PO3C} polyhedra are cross-linked by 2-pmb3- ligands. The carboxylic groups of 2-pmbH2- ligands are pendant on the two sides of the layers and form hydrogen bonds between the layers. Both compounds can be exfoliated in acetone via a top-down freeze-thaw method, resulting in nanosheets of two-layer thickness. Interestingly, the photoluminescence (PL) of 1 and 2 is highly temperature sensitive. Variable temperature PL studies revealed that compounds 1 and 2 can be used as thermometers in the temperature ranges 120-300 K and 100-280 K, respectively. By doping the nanosheets into polymer matrix, 1-ns@PMMA and 2-ns@PMMA were prepared. The PL intensity of 1-ns@PMMA is insensitive to temperature, unlike that of the bulk sample. While 2-ns@PMMA exhibits similar temperature-dependent luminescence behaviour to its bulk counterpart, thereby enabling its potential application as a thermometer in the temperature range 100-280 K.

19.
Eur J Cancer ; 150: 23-30, 2021 06.
Article in English | MEDLINE | ID: mdl-33882375

ABSTRACT

OBJECTIVE: Leptomeningeal metastases (LM) occur in up to 5% of non-small cell lung cancer (NSCLC) patients and often develop after previous systemic treatments. In this article, we explored whether immune checkpoint inhibitors (ICIs) enhanced the dismal survival of patients with LM. MATERIALS AND METHODS: Data on NSCLC patients with LM prescribed ICIs were collected at the Guangdong Lung Cancer Institute. Furthermore, relevant literature was reviewed. RESULTS: A total of 255 NSCLC patients diagnosed with LM were screened from January 2015 to March 2020 at our institute. Cases reported by literature were also included. Finally, 32 NSCLC patients received ICIs after LM diagnosis; their median age was 55 years. Druggable genes were detected in 37.5% of all patients. The ICI regimens included nivolumab (n = 21), pembrolizumab (n = 9), and atezolizumab (n = 2). Ultimately, 62.5% of patients evidenced neurological symptom controlled. Two patients exhibited both intracranial and extracranial complete tumour response; one patient showed both intracranial and extracranial partial response (PR), one patient indicated intracranial PR and a systemic PR, and one patient showed central nervous system PR without extracranial response reported. The median progression-free survival (PFS) in the single-agent subgroup was 2.1 months (95% confidence interval [CI]: 1.4-2.9 months), and the median overall survival (OS) was 4.0 months (95% CI: 0.1-13.3 months). In the combined subgroup, the median PFS and OS were 3.0 months (95% CI: 1.1-4.9 months) and 5.4 months (95% CI: 0.5-10.3 months), respectively. Three patients exhibited remarkable PFS of over 20 months: all patients had ICI single agent, received cranial radiotherapy before ICI prescription, and took ICIs as second-line therapy, and two patients were EGFR/ALK wild type. Multivariate analysis showed that a better Eastern Cooperative Oncology Group Performance Status (ECOG-PS) score was associated with prolonged PFS (P = 0.04). No difference in survival was seen between monotherapy and combination therapy groups. CONCLUSION: NSCLC patients with LM may benefit from ICIs of both monotherapy and combination with other therapies, especially those with good ECOG-PS scores. Further work in this regard is required.


Subject(s)
Carcinoma, Non-Small-Cell Lung/drug therapy , Immune Checkpoint Inhibitors/therapeutic use , Lung Neoplasms/drug therapy , Meningeal Carcinomatosis/drug therapy , Adult , Aged , Aged, 80 and over , Carcinoma, Non-Small-Cell Lung/immunology , Carcinoma, Non-Small-Cell Lung/mortality , Carcinoma, Non-Small-Cell Lung/secondary , Disease Progression , Female , Humans , Immune Checkpoint Inhibitors/adverse effects , Lung Neoplasms/immunology , Lung Neoplasms/mortality , Lung Neoplasms/pathology , Male , Meningeal Carcinomatosis/immunology , Meningeal Carcinomatosis/mortality , Meningeal Carcinomatosis/secondary , Middle Aged , Progression-Free Survival , Retrospective Studies , Time Factors
20.
Article in English | MEDLINE | ID: mdl-18391576

ABSTRACT

PURPOSE: The aim of this study was to evaluate the suppression effect of survivin shRNA on the expression of the survivin gene in the human laryngeal cancer cell line Hep-2. PROCEDURES: 60 cases of laryngeal squamous-cell carcinoma (LSCC) and 10 cases of normal laryngeal mucosa were examined using immunohistochemistry to determine whether the expression of survivin correlated with tumorigenesis. Three plasmid vectors of short hairpin RNA (shRNA) specific for survivin were designed and generated. Western blot and real-time PCR analysis of survivin expression in Hep-2 cells was performed 48 h after transfection. The growth curve was used to determine the cell proliferation. Propidium iodide (PI) single staining was applied to detect the cell cycle. The apoptosis of the cells was analyzed by flow cytometry with the FITC-annexin-V/PI double staining and PI single staining. RESULTS: 68.33% (41 out of 60) of tumors were positive for survivin expression and significantly associated with lymph node metastasis and advanced stage. In contrast, no expression of survivin in normal mucosa was detected. Transfection of Hep-2 cells with survivin shRNA significantly inhibited survivin expression at both the mRNA and the protein level in Hep-2 cells. Downregulation of survivin resulted in increasing the apoptosis index, but the results showed no obvious influence on cell cycle. CONCLUSIONS: This study demonstrates that survivin shRNA effectively inhibits survivin gene expression in Hep-2 cells leading to growth suppression and apoptotic induction in Hep-2 cells.


Subject(s)
Apoptosis , Carcinoma, Squamous Cell/physiopathology , Laryngeal Neoplasms/physiopathology , Microtubule-Associated Proteins/antagonists & inhibitors , Microtubule-Associated Proteins/genetics , Neoplasm Proteins/antagonists & inhibitors , Neoplasm Proteins/genetics , RNA Interference , Carcinoma, Squamous Cell/etiology , Carcinoma, Squamous Cell/metabolism , Carcinoma, Squamous Cell/pathology , Cell Line, Tumor , Cell Proliferation , Down-Regulation , Female , Gene Expression , Humans , Immunohistochemistry , Inhibitor of Apoptosis Proteins , Laryngeal Neoplasms/etiology , Laryngeal Neoplasms/metabolism , Laryngeal Neoplasms/pathology , Lymphatic Metastasis , Male , Microtubule-Associated Proteins/metabolism , Middle Aged , Neoplasm Proteins/metabolism , RNA, Messenger/antagonists & inhibitors , Survivin
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