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1.
Cell ; 178(6): 1478-1492.e20, 2019 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-31474362

RESUMO

Liver fibrosis is a very common condition seen in millions of patients with various liver diseases, and yet no effective treatments are available owing to poorly characterized molecular pathogenesis. Here, we show that leukocyte cell-derived chemotaxin 2 (LECT2) is a functional ligand of Tie1, a poorly characterized endothelial cell (EC)-specific orphan receptor. Upon binding to Tie1, LECT2 interrupts Tie1/Tie2 heterodimerization, facilitates Tie2/Tie2 homodimerization, activates PPAR signaling, and inhibits the migration and tube formations of EC. In vivo studies showed that LECT2 overexpression inhibits portal angiogenesis, promotes sinusoid capillarization, and worsens fibrosis, whereas these changes were reversed in Lect2-KO mice. Adeno-associated viral vector serotype 9 (AAV9)-LECT2 small hairpin RNA (shRNA) treatment significantly attenuates fibrosis. Upregulation of LECT2 is associated with advanced human liver fibrosis staging. We concluded that targeting LECT2/Tie1 signaling may represent a potential therapeutic target for liver fibrosis, and serum LECT2 level may be a potential biomarker for the screening and diagnosis of liver fibrosis.


Assuntos
Células Endoteliais/metabolismo , Hepatócitos/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Cirrose Hepática/metabolismo , Fígado/metabolismo , Receptores de TIE/metabolismo , Animais , Biomarcadores/metabolismo , Capilares/metabolismo , Células Endoteliais/citologia , Células Endoteliais/patologia , Células HEK293 , Hepatócitos/citologia , Hepatócitos/patologia , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Fígado/irrigação sanguínea , Fígado/patologia , Cirrose Hepática/diagnóstico , Camundongos Endogâmicos C57BL
2.
Proc Natl Acad Sci U S A ; 121(20): e2318384121, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38713627

RESUMO

The reaction kinetics of photocatalytic CO2 reduction is highly dependent on the transfer rate of electrons and protons to the CO2 molecules adsorbed on catalytic centers. Studies on uncovering the proton effect in catalysts on photocatalytic activity of CO2 reduction are significant but rarely reported. In this paper, we, from the molecular level, revealed that the photocatalytic activity of CO2 reduction is closely related to the proton availability in catalysts. Specifically, four dinuclear Co(II) complexes based on Robson-type ligands with different number of carboxylic groups (-nCOOH; n = 0, 2, 4, 6) were designed and synthesized. All these complexes show photocatalytic activity for CO2 reduction to CO in a water-containing system upon visible-light illumination. Interestingly, the CO yields increase positively with the increase of the carboxylic-group number in dinuclear Co(II) complexes. The one containing -6COOH shows the best photocatalytic activity for CO2 reduction to CO, with the TON value reaching as high as 10,294. The value is 1.8, 3.4, and 7.8 times higher than those containing -4COOH, -2COOH, and -0COOH, respectively. The high TON value also makes the dinuclear Co(II) complex with -6COOH outstanding among reported homogeneous molecular catalysts for photocatalytic CO2 reduction. Control experiments and density functional theory calculation indicated that more carboxylic groups in the catalyst endow the catalyst with more proton relays, thus accelerating the proton transfer and boosting the photocatalytic CO2 reduction. This study, at a molecular level, elucidates that more carboxylic groups in catalysts are beneficial for boosting the reaction kinetics of photocatalytic CO2 reduction.

3.
Plant Physiol ; 195(1): 395-409, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38198215

RESUMO

Dwarfism is an important agronomic trait in fruit breeding programs. However, the germplasm resources required to generate dwarf pear (Pyrus spp.) varieties are limited. Moreover, the mechanisms underlying dwarfism remain unclear. In this study, "Yunnan" quince (Cydonia oblonga Mill.) had a dwarfing effect on "Zaosu" pear. Additionally, the dwarfism-related NAC transcription factor gene PbNAC71 was isolated from pear trees comprising "Zaosu" (scion) grafted onto "Yunnan" quince (rootstock). Transgenic Nicotiana benthamiana and pear OHF-333 (Pyrus communis) plants overexpressing PbNAC71 exhibited dwarfism, with a substantially smaller xylem and vessel area relative to the wild-type controls. Yeast one-hybrid, dual-luciferase, chromatin immunoprecipitation-qPCR, and electrophoretic mobility shift assays indicated that PbNAC71 downregulates PbWalls are thin 1 expression by binding to NAC-binding elements in its promoter. Yeast two-hybrid assays showed that PbNAC71 interacts with the E3 ubiquitin ligase PbRING finger protein 217 (PbRNF217). Furthermore, PbRNF217 promotes the ubiquitin-mediated degradation of PbNAC71 by the 26S proteasome, thereby regulating plant height as well as xylem and vessel development. Our findings reveal a mechanism underlying pear dwarfism and expand our understanding of the molecular basis of dwarfism in woody plants.


Assuntos
Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Plantas Geneticamente Modificadas , Pyrus , Fatores de Transcrição , Xilema , Xilema/metabolismo , Xilema/genética , Pyrus/genética , Pyrus/metabolismo , Pyrus/crescimento & desenvolvimento , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Nicotiana/genética , Nicotiana/metabolismo , Nicotiana/crescimento & desenvolvimento , Regiões Promotoras Genéticas/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Complexo de Endopeptidases do Proteassoma/genética
4.
Proc Natl Acad Sci U S A ; 119(11): e2118278119, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35263220

RESUMO

SignificanceThe photosensitizer is one of the important components in the photocatalytic system. Molecular photosensitizers have well-defined structures, which is beneficial in revealing the catalysis mechanism and helpful for further structural design and performance optimization. However, separation and recycling of the molecular photosensitizers is a great problem. Loading them into/on two/three-dimensional supports through covalent bonds, electrostatic interactions, and supramolecular interactions is a method that enhances their separation and recycling capability. Nonetheless, the structures of the resulting composites are unclear. Thus, the development of highly crystalline heterogeneity methods for molecular photosensitizers, albeit greatly challenging, is meaningful and desirable in photocatalysis, through which heterogeneous photosensitizers with well-defined structures, definite catalysis mechanisms, and good catalytic performance would be expected.


Assuntos
Fármacos Fotossensibilizantes , Catálise , Estrutura Molecular , Fármacos Fotossensibilizantes/química
5.
BMC Genomics ; 25(1): 354, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594645

RESUMO

The homeodomain-leucine zipper (HD-Zip) gene family plays a pivotal role in plant development and stress responses. Nevertheless, a comprehensive characterization of the HD-Zip gene family in kiwifruit has been lacking. In this study, we have systematically identified 70 HD-Zip genes in the Actinidia chinensis (Ac) genome and 55 in the Actinidia eriantha (Ae) genome. These genes have been categorized into four subfamilies (HD-Zip I, II, III, and IV) through rigorous phylogenetic analysis. Analysis of synteny patterns and selection pressures has provided insights into how whole-genome duplication (WGD) or segmental may have contributed to the divergence in gene numbers between these two kiwifruit species, with duplicated gene pairs undergoing purifying selection. Furthermore, our study has unveiled tissue-specific expression patterns among kiwifruit HD-Zip genes, with some genes identified as key regulators of kiwifruit responses to bacterial canker disease and postharvest processes. These findings not only offer valuable insights into the evolutionary and functional characteristics of kiwifruit HD-Zips but also shed light on their potential roles in plant growth and development.


Assuntos
Actinidia , Proteínas de Homeodomínio , Proteínas de Homeodomínio/genética , Genoma de Planta , Filogenia , Actinidia/genética , Zíper de Leucina/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Perfilação da Expressão Gênica
6.
Small ; : e2311555, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38651533

RESUMO

Ultramicroporous metal-organic frameworks (MOFs) are demonstrated to be advantageous for the separation and purification of light hydrocarbons such as C2H2, C2H4, and CH4. The introduction of transition metal sites with strong π-complexation affinity into MOFs is more effective than other adsorption sites for the selective adsorption of π-electron-rich unsaturated hydrocarbon gases from their mixtures. However, lower coordination numbers make it challenging to produce robust MOFs directly utilizing metal ions with π-coordination activity, such as Cu+, Ag+, and Pd2+. Herein, a series of novel π-complexing MOFs (SNNU-33s) with a pore size of 4.6 Å are precisely constructed by cleverly introducing symmetrically matched C3-type [Cu(pyz)3] (pyz = pyrazine) coordinated fragments into 1D hexagonal channels of MIL-88 prototype frameworks. Benifit from the spatial confinement combined with π-complex-active Cu+ of [Cu(pyz)3], pore-space-partitioned SNNU-33 MOFs all present excellent C2H2/CH4, C2H4/CH4, and CO2/CH4 separation ability. Notably, the optimized SNNU-33b adsorbent demonstrates top-level IAST selectivity values for C2H2/CH4 (597.4) and C2H4/CH4 (69.8), as well as excellent breakthrough performance. Theoretical calculations further reveal that such benchmark light hydrocarbon separation and purification ability is mainly ascribed to the extra-strong binding affinity between Cu+ and π-electron donor molecules via a spatially confined π-complexation process.

7.
J Transl Med ; 22(1): 215, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38424641

RESUMO

BACKGROUND: Cardiovascular diseases (CVDs) are the leading cause of death around the world. Most CVDs-related death can be prevented by the optimal management of risk factors such as unhealthy diet and physical inactivity. Clinical practice guidelines (CPGs) for CVDs, provide some evidence-based recommendations which help healthcare professionals to achieve the best care for patients with CVDs. This systematic review aims to appraise the methodological quality of CPGs systematically and summarize the recommendations of self-managed non-pharmacological interventions for the prevention and management of CVDs provided by the selected guidelines. METHODS: A comprehensive electronic literature search was conducted via six databases (PubMed, Medline, The Cochrane Library, Embase, CINAHL, and Web of Science), seven professional heart association websites, and nine guideline repositories. The Appraisal of Guidelines, Research and Evaluation II (AGREE II) instrument was adopted to critically appraise the methodological quality of the selected guidelines. Content analysis was used to summarise recommended self-managed non-pharmacological interventions for CVDs. RESULTS: Twenty-three CPGs regarding different CVDs were included, in which four guidelines of CVDs, three for coronary heart diseases, seven for heart failure, two for atrial fibrillation, three for stroke, three for peripheral arterial disease, and one for hypertrophic cardiomyopathy. Twenty CPGs were appraised as high quality, and three CPGs as moderate quality. All twenty-three CPGs were recommended for use with or without modification. The domain of "Editorial Independence" had the highest standardized percentage (93.47%), whereas the domain of "Applicability" had the lowest mean domain score of 75.41%. The content analysis findings summarised some common self-managed non-pharmacological interventions, which include healthy diet, physical activity, smoking cessation, alcohol control, and weight management. Healthy diet and physical acidity are the most common and agreed on self-managed interventions for patients with CVDs. There are some inconsistencies identified in the details of recommended interventions, the intervention itself, the grade of recommendation, and the supported level of evidence. CONCLUSION: The majority of the summarized non-pharmacological interventions were strongly recommended with moderate to high-quality levels of evidence. Healthcare professionals and researchers can adopt the results of this review to design self-managed non-pharmacological interventions for patients with CVDs.


Assuntos
Doenças Cardiovasculares , Insuficiência Cardíaca , Doença Arterial Periférica , Autogestão , Humanos , Doenças Cardiovasculares/terapia , Guias de Prática Clínica como Assunto
8.
Cytotherapy ; 26(2): 113-125, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37999667

RESUMO

BACKGROUND AIMS: Peritoneal carcinomatosis (PC) from colorectal cancer (CRC) is a highly challenging disease to treat. Systemic chimeric antigen receptor (CAR) T cells have shown impressive efficacy in hematologic malignancies but have been less effective in solid tumors. We explored whether intraperitoneal (i.p.) administration of CAR T cells could provide an effective and robust route of treatment for PC from CRC. METHODS: We generated second-generation carcinoembryonic antigen (CEA)-specific CAR T cells. Various animal models of PC with i.p. and extraperitoneal metastasis were treated by i.p. or intravenous (i.v.) administration of CEA CAR T cells. RESULTS: Intraperitoneally administered CAR T cells exhibited superior anti-tumor activity compared with systemic i.v. cell infusion in an animal model of PC. In addition, i.p. administration conferred a durable effect and protection against tumor recurrence and exerted strong anti-tumor activity in an animal model of PC with metastasis in i.p. or extraperitoneal organs. Moreover, compared with systemic delivery, i.p. transfer of CAR T cells provided increased anti-tumor activity in extraperitoneal tumors without PC. This phenomenon was further confirmed in an animal model of pancreatic carcinoma after i.p. administration of our newly constructed prostate stem cell antigen-directed CAR T cells. CONCLUSIONS: Taken together, our data suggest that i.p. administration of CAR T cells may be a robust delivery route for effective treatment of cancer.


Assuntos
Neoplasias Colorretais , Neoplasias Peritoneais , Receptores de Antígenos Quiméricos , Masculino , Animais , Antígeno Carcinoembrionário , Neoplasias Peritoneais/terapia , Linfócitos T , Imunoterapia Adotiva , Recidiva Local de Neoplasia , Neoplasias Colorretais/terapia , Neoplasias Colorretais/patologia
9.
Support Care Cancer ; 32(6): 370, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38776028

RESUMO

OBJECTIVE: Immune checkpoint inhibitors (ICIs), specifically targeting the programmed cell death protein-1 or its ligand (PD-1/PD-L1), have been extensively used in the treatment of a spectrum of malignancies, although the predictive biomarkers remain to be elucidated. This study aims to investigate the association between baseline circulating levels of cytokines and the creatinine/cystatin C ratio (CCR) with the treatment outcomes of ICIs in patients with advanced cancer. METHODS: The pre-treatment circulating levels of 10 cytokines (PD-L1, CTLA4, CXCL10, LAG3, HGF, CCL2, MIG, GRANB, IL-18, and IL-6) were measured via automated capillary-based immunoassay platform in the serum of 65 advanced cancer patients treated with anti-PD-1/PD-L1-based systemic therapy and 10 healthy volunteers. The levels of cytokines and CCR were quantified and categorized into high and low groups based on the median value. The associations of serum cytokines and CCR with response to treatment, survival, and immune-related adverse events were assessed. RESULTS: Elevated circulating levels of 6 cytokines (PD-L1, CXCL10, HGF, CCL2, MIG, and IL-6) were observed in cancer patients compared with that in healthy volunteers. The correlation coefficients between cytokines, CCR and nutritional risk index were also calculated. In the cancer cohort (N = 65), low circulating HGF (P = 0.023, P = 0.029), low IL-6 (P = 0.002, P < 0.001), and high CCR (P = 0.031, P = 0.008) were associated with significantly improved progression-free survival (PFS) and overall survival (OS). Multi-variable COX analyses adjusted for clinicopathological factors revealed that low HGF, low IL-6, and high CCR were independent favorable prognostic factors for PFS (P = 0.028, P = 0.010, and P = 0.015, respectively) and OS (P = 0.043, P = 0.003, and P = 0.026, respectively). Grade 2 irAEs occurred more frequently in patients with low levels of circulating CCL2 and LAG3. CONCLUSIONS: Pre-treatment circulating levels of serum IL-6, HGF, and CCR may serve as independent predictive and prognostic biomarkers in advanced cancer patients treated with ICIs-based systemic therapy. These findings might help to identify potential patients who would benefit from these therapies.


Assuntos
Biomarcadores Tumorais , Creatinina , Citocinas , Inibidores de Checkpoint Imunológico , Neoplasias , Humanos , Masculino , Feminino , Neoplasias/tratamento farmacológico , Neoplasias/sangue , Pessoa de Meia-Idade , Idoso , Citocinas/sangue , Prognóstico , Inibidores de Checkpoint Imunológico/uso terapêutico , Inibidores de Checkpoint Imunológico/farmacologia , Creatinina/sangue , Biomarcadores Tumorais/sangue , Adulto , Idoso de 80 Anos ou mais , Antígeno B7-H1/sangue , Estudos de Casos e Controles
10.
Artigo em Inglês | MEDLINE | ID: mdl-38466058

RESUMO

Objective: Our study aimed to investigate the clinical efficacy of hightibialosteotomy (HTO) posterior plate placement combined with arthroscopic surgery for degenerative injury of the posterior horn of the medial meniscus with poor force lines in the lower extremity, improve joint function or relieve pain. Methods: The case data of 98 patients with osteoarthritis of the knee admitted to the Department of Orthopedics in our hospital from January 2019 to January 2023 were selected for retrospective analysis. The patients were divided into 54 patients, each in the study group and the comparison group according to the different treatment regimens. The study group received hightibialosteotomy plate placement combined with arthroscopic surgery, while the comparison group underwent hightibialosteotomy plate placement alone. The differences in knee scores, knee Lysholm scores, Lysholm scores, Healthcare Security and Safety (HSS) scores, Tegner scores, Visual Analog Scale (VAS), lower extremity force lines, femorotibial angles, and tibial plateau were counted and compared between the two groups. Results: HSS knee function scores, Lysholm scores, and VAS scores of the study group were statistically significant compared with those of the comparison group at the final follow-up of patients, and the postoperative clinical outcomes improved significantly (P < .05). The differences in Hip-Knee-Ankle(HKA) angle andMedial-Pateral Tibial Angle (MPTA) of patients in the study group were statistically significant compared with the comparison group, and the increase in HKA (12.31±2.13)°, MPTA (11.84±2.32)° and lower limb force line was significantly improved (P < .05). Preoperatively, there was no statistically significant comparison between the visual analog scores of the knee joint in the study group and the comparison group. After surgery, the difference between the two groups was statistically significant (P < .05). The relative position of the mechanical axis of the lower limb through the tibial plateau, the femorotibial angle, and the posterior tibial plateau angle increased in patients after surgery, and the differences were statistically significant when compared with the preoperative period (P < .05). Both the tibial posterior displacement distance and the lateral knee gap opening were reduced compared with the preoperative period, and the differences were statistically significant (P < .05). Conclusion: Hightibialosteotomy after plate placement combined with arthroscopic surgery has better clinical efficacy in the early stage and can effectively treat the degenerative injury of the posterior horn of the medial meniscus with poor force lines in the lower limb, improve the joint function, and relieve the symptoms of patients.

11.
BMC Nurs ; 23(1): 180, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38486252

RESUMO

AIMS: This study was designed to develop a biosafety incident response competence scale and evaluate its validity and reliability among clinical nurses. DESIGN: This study employed a sequential approach, comprising four phases: (1) the establishment of a multidimensional conceptual model, (2) the preliminary selection of the items, (3) further exploration and psychometric testing of the items, (4) the application of the scale among clinical nurses. METHODS: The biosafety incident response competence conceptual model was developed through literature review and the Delphi method. A total of 1,712 clinical nurses participated in the preliminary items selection, while 1,027 clinical nurses were involved in the further psychometric testing from July 2023 to August 2023. The item analysis, exploratory factor analysis and confirmatory factor analysis were conducted to evaluate the construct validity. Reliability was measured using Cronbach's alpha, split-half reliability, and test-retest reliability, while validity analysis included content validity, structural validity, convergent validity, and discriminant validity. From September to November 2023, we conducted a survey using the established scale with a total of 4338 valid questionnaires collected. T-test and variance analysis was employed to determine potential variations in biosafety incident response competence based on participants characteristics. RESULTS: The final scale is composed of 4 factors and 29 items, including monitoring and warning abilities, nursing disposal abilities, biosafety knowledge preparedness, and infection protection abilities. The explanatory variance of the 4 factors was 75.100%. The Cronbach's alpha, split-half reliability and test-retest reliability were 0.974, 0.945 and 0.840 respectively. The Scale-level content validity index was 0.866. The Average Variance Extracted of the 4 factors was larger than 0.5, the Construct Reliability was larger than 0.7, and the Heterotrait-Monotrait ratio were less than 0.9. There were significant differences in the scores of response competence among nurses of different ages, working years, titles, positions, departments, marital status and participation in biosafety training (all P < 0.05). CONCLUSIONS: The biosafety incident response competence scale for nurses exhibits satisfactory reliability and validity, making it a valuable tool for assessing clinical nurses' abilities in responding to biosafety incidents.

12.
BMC Nurs ; 23(1): 221, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561710

RESUMO

BACKGROUND: The outbreak of Corona Virus Disease (COVID-19) in 2019 has continued until now, posing a huge threat to the public's physical and mental health, resulting in different degrees of mental health problems. As a vulnerable segment of the public, anxiety is one of the most common mental health problems among COVID-19 patients. Excessive anxiety aggravates the physical and psychological symptoms of COVID-19 patients, which is detrimental to their treatment and recovery, increases financial expenditure, affects family relations, and adds to the medical burden. OBJECTIVE: This study aimed to explore the role of psychological capital and self-esteem in the relationship between insomnia and anxiety, thereby shedding light on the mechanism of the effect of insomnia on anxiety in COVID-19 patients. METHODS: A cross-sectional study was conducted from April to May 2022 in Fangcang hospital in Shanghai, China. The self-administered questionnaires were distributed to 718 COVID-19 patients via cell phone using the Internet platform "Questionnaire Star", which included Athens Insomnia Scale, Psychological Capital Questionnaire, Self-esteem Scale, Self-Rating Anxiety Scale, gender, age, marital status, education. Data analysis was performed using descriptive analysis, independent-samples t-test, one-way analysis of variance, Pearson correlation analysis, ordinary least-squares regression, and bootstrap method. RESULTS: Education background had significant impact on anxiety in COVID-19 patients (F = 7.70, P < 0.001). Insomnia, psychological capital, self-esteem and anxiety were significantly correlated, respectively (P < 0.001). And Regression analysis showed that insomnia had a direct negative predictive effect on psychological capital (ß = -0.70, P < 0.001) and self-esteem (ß = -0.13, P < 0.001). Psychological capital had a direct positive predictive effect on self-esteem (ß = 0.12, P < 0.001). Insomnia had a direct positive predictive effect on anxiety (ß = 0.61, P < 0.001). Both psychological capital and self-esteem had significant negative predictive effects on anxiety (ß = -0.06, P < 0.05; ß = -0.72, P < 0.001). The results showed that the mediating effect of psychological capital and self-esteem was significant, and the mediating effect value was 0.21. First, the indirect effect consisting of insomnia - psychological capital - anxiety was 0.04, showing that psychological capital had a significant mediating effect. Second, the indirect effect consisting of insomnia-self-esteem-anxiety had a value of 0.10, indicating that self-esteem had a significant mediating effect. Third, the indirect effect consisting of insomnia-psychological capital-self-esteem-anxiety had a value of 0.06, suggesting that psychological capital and self-esteem had a significant chain mediating effect between insomnia and anxiety. CONCLUSIONS: Insomnia had a significant positive predictive effect on anxiety. Insomnia was first associated with a decrease in psychological capital, followed by a sequential decrease in self-esteem, which in turn was associated with increased anxiety symptoms in COVID-19 patients. Therefore, focusing on improving the psychological capital and self-esteem of patients can help alleviate the anxiety caused by insomnia in COVID-19 patients. It is recommended that patients and health care professionals increase the psychological capital and Self-esteem of COVID-19 patients through various methods to counter the effects of insomnia on anxiety.

13.
Angew Chem Int Ed Engl ; 63(15): e202400172, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38345140

RESUMO

A negatively curved aza-nanographene (NG) containing two octagons was synthesized by a regioselective and stepwise cyclodehydrogenation procedure, in which a double aza[7]helicene was simultaneously formed as an intermediate. Their saddle-shaped structures with negative curvature were unambiguously confirmed by X-ray crystallography, thereby enabling the exploration of the structure-property relationship by photophysical, electrochemical and conformational studies. Moreover, the assembly of the octagon-embedded aza-NG with fullerenes was probed by fluorescence spectral titration, with record-high binding constants (Ka=9.5×103 M-1 with C60, Ka=3.7×104 M-1 with C70) found among reported negatively curved polycyclic aromatic compounds. The tight association of aza-NG with C60 was further elucidated by X-ray diffraction analysis of their co-crystal, which showed the formation of a 1 : 1 complex with substantial concave-convex interactions.

14.
Plant Biotechnol J ; 21(3): 560-573, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36448454

RESUMO

Currently, feed enzymes are primarily obtained through fermentation of fungi, bacteria, and other microorganisms. Although the manufacturing technology for feed enzymes has evolved rapidly, the activities of these enzymes decline during the granulating process and the cost of application has increased over time. An alternative approach is the use of genetically modified plants containing complex feed enzymes for direct utilization in animal feedstuff. We co-expressed three commonly used feed enzymes (phytase, ß-glucanase, and xylanase) in barley seeds using the Agrobacterium-mediated transformation method and generated a new barley germplasm. The results showed that these enzymes were stable and had no effect on the development of the seeds. Supplementation of the basal diet of laying hens with only 8% of enzyme-containing seeds decreased the quantities of indigestible carbohydrates, improved the availability of phosphorus, and reduced the impact of animal production on the environment to an extent similar to directly adding exogenous enzymes to the feed. Feeding enzyme-containing seeds to layers significantly increased the strength of the eggshell and the weight of the eggs by 10.0%-11.3% and 5.6%-7.7% respectively. The intestinal microbiota obtained from layers fed with enzyme-containing seeds was altered compared to controls and was dominated by Alispes and Rikenella. Therefore, the transgenic barley seeds produced in this study can be used as an ideal feedstuff for use in animal feed.


Assuntos
6-Fitase , Hordeum , Animais , Feminino , Galinhas , Dieta , Sementes , Engenharia Genética , Ração Animal/análise , Suplementos Nutricionais , Fenômenos Fisiológicos da Nutrição Animal
15.
Hepatology ; 76(3): 660-675, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-34940991

RESUMO

BACKGROUND AND AIMS: No effective treatments are available for liver fibrosis. Angiogenesis is deeply involved in liver fibrogenesis. However, current controversial results suggest it is difficult to treat liver fibrosis through vascular targeting. There are three different microvessels in liver: portal vessels, liver sinusoids, and central vessels. The changes and roles for each of the three different vessels during liver fibrogenesis are unclear. We propose that they play different roles during liver fibrogenesis, and a single vascular endothelial cell (EC) regulator is not enough to fully regulate these three vessels to treat liver fibrosis. Therefore, a combined regulation of multiple different EC regulatory signaling pathway may provide new strategies for the liver fibrosis therapy. Herein, we present a proof-of-concept strategy by combining the regulation of leukocyte cell-derived chemotaxin 2 (LECT2)/tyrosine kinase with immunoglobulin-like and epidermal growth factor-like domains 1 signaling with that of vascular endothelial growth factor (VEGF)/recombinant VEGF (rVEGF) signaling. APPROACH AND RESULTS: The CCl4 -induced mouse liver fibrosis model and NASH model were both used. During fibrogenesis, vascular changes occurred at very early stage, and different liver vessels showed different changes and played different roles: decreased portal vessels, increased sinusoid capillarization and the increased central vessels the increase of portal vessels alleviates liver fibrosis, the increase of central vessels aggravates liver fibrosis, and the increase of sinusoid capillarization aggravates liver fibrosis. The combinational treatment of adeno-associated viral vector serotype 9 (AAV9)-LECT2-short hairpin RNA (shRNA) and rVEGF showed improved therapeutic effects, but it led to serious side effects. The combination of AAV9-LECT2-shRNA and bevacizumab showed both improved therapeutic effects and decreased side effects. CONCLUSIONS: Liver vascular changes occurred at very early stage of fibrogenesis. Different vessels play different roles in liver fibrosis. The combinational treatment of AAV9-LECT2-shRNA and bevacizumab could significantly improve the therapeutic effects on liver fibrosis.


Assuntos
Cirrose Hepática , Fator A de Crescimento do Endotélio Vascular , Animais , Bevacizumab/efeitos adversos , Modelos Animais de Doenças , Fígado/patologia , Cirrose Hepática/metabolismo , Camundongos , RNA Interferente Pequeno/uso terapêutico , Fator A de Crescimento do Endotélio Vascular/metabolismo
16.
Chemistry ; 29(44): e202301028, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37221138

RESUMO

Direct conversion of methane to high-value-added transportable methanol is a great challenge, which requires high energy input to break the strong C-H bond. Developing efficient catalysts for methane oxidation to methanol under mild conditions is of vital importance. In this work, single transition metal atoms (TM=Fe, Co, Ni, Cu) anchored on black phosphorus (TM@BP) were studied as catalysts to assist the methane oxidation to methanol by means of first-principles calculations. The results indicate that Cu@BP exhibits an outstanding catalytic activity through the radical reaction pathways and the formation of the Cu-O active site is rate-determining with an energy barrier of 0.48 eV. Meanwhile, electronic structure calculations and dynamic simulations show that Cu@BP offers excellent thermal stability. Our calculations provide a new approach for the rational design of single atom catalysts for methane oxidation to methanol.

17.
Virol J ; 20(1): 114, 2023 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-37280711

RESUMO

BACKGROUND: COVID-19 infection continues all over the world, causing serious physical and psychological impacts to patients. Patients with COVID-19 infection suffer from various negative emotional experiences such as anxiety, depression, mania, and alienation, which seriously affect their normal life and is detrimental to the prognosis. Our study is aimed to investigate the effect of psychological capital on alienation among patients with COVID-19 and the mediating role of social support in this relationship. METHODS: The data were collected in China by the convenient sampling. A sample of 259 COVID-19 patients completed the psychological capital, social support and social alienation scale and the structural equation model was adopted to verify the research hypotheses. RESULTS: Psychological capital was significantly and negatively related to the COVID-19 patients' social alienation (p < .01). And social support partially mediated the correlation between psychological capital and patients' social alienation (p < .01). CONCLUSION: Psychological capital is critical to predicting COVID-19 patients' social alienation. Social support plays an intermediary role and explains how psychological capital alleviates the sense of social alienation among patients with COVID-19 infection.


Assuntos
COVID-19 , Capital Social , Isolamento Social , Apoio Social , COVID-19/psicologia , Humanos , China , Análise de Mediação , Modelos Psicológicos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Intervalos de Confiança
18.
BMC Psychiatry ; 23(1): 90, 2023 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-36747156

RESUMO

BACKGROUND: The aim of this study was to understand the longitudinal trajectory of suicidal ideation (SI) among Chinese medical students and the role of childhood trauma (CT). METHODS: Using a whole-group sampling method, we assessed SI in 2192 (male = 834, female = 1358) medical students on three occasions over a period of one year. The Suicidal Ideation Self-Assessment Scale (SISAS) and the Childhood Trauma Questionnaire-Short Form (CTQ-SF) were used to assess SI and CT. The growth mixture modeling (GMM) was used to classify the developmental trajectory of SI. RESULTS: A greater number of medical students were experiencing suicidal ideation during the COVID-19 pandemic. The trajectory of SI among medical students was divided into two groups: a low risk, slowly rising group and a high risk, continuous group. The low risk, slowly rising group had a significant time effect (B = 1.57, p < 0.001) and showed a slowly increasing trend. Emotional neglect (EN), physical neglect (PN), emotional abuse (EA) and physical abuse (PA) all had significant positive predictive effects for the high risk, continuous group (B = 0.18-0.65, P < 0.01). CONCLUSION: The trajectory of SI among medical students can be divided into a low risk, slowly rising group and a high risk, continuous group; the more EN, PN, EA and PA experienced during childhood, the more likely medical students are to develop a high risk, continuous state of SI.


Assuntos
Experiências Adversas da Infância , COVID-19 , Estudantes de Medicina , Humanos , Masculino , Feminino , Ideação Suicida , Pandemias , Inquéritos e Questionários
19.
BMC Psychiatry ; 23(1): 516, 2023 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-37464335

RESUMO

BACKGROUND: work alienation is receiving increasing attention as a psychological risk at work, and little is known about the mechanisms of role ambiguity and work alienation in nurses in the context of the COVID-19 pandemic. This article aims to examine how role ambiguity affects work alienation among Chinese nurses during the two years after COVID-19 pandemic and verify emotional exhaustion as mediators. METHODS: A cross-sectional study design was used to recruit 281 Chinese nurses. Nurses completed online questionnaires containing demographic characteristics, role ambiguity, emotional exhaustion, and work alienation, and SPSS 26.0 and AMOS 24.0 were used for data analysis and structural equation modelling. RESULTS: work alienation scores were (34.64 ± 10.09), work alienation was correlated with role ambiguity and emotional exhaustion (r1 = 0.521, r2 = 0.755; p < .01), and role ambiguity was positively correlated with emotional exhaustion (r = 0.512; p < .01). A mediating effect of emotional exhaustion between role ambiguity and work alienation held (mediating effect of 0.288, 95% CI: 0.221-0.369, accounting for 74.8% of the total effect). CONCLUSION: Role ambiguity has a significant direct effect on nurses' feelings of alienation and exacerbates alienation through emotional exhaustion. Clarifying roles at work and being less emotionally drained are effective ways to reduce nurses' feelings of alienation.


Assuntos
Esgotamento Profissional , COVID-19 , Enfermeiras e Enfermeiros , Recursos Humanos de Enfermagem Hospitalar , Humanos , Estudos Transversais , População do Leste Asiático , Pandemias , Esgotamento Profissional/psicologia , Recursos Humanos de Enfermagem Hospitalar/psicologia , Emoções , Inquéritos e Questionários
20.
Ecotoxicol Environ Saf ; 262: 115287, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37567105

RESUMO

2,4-Dinitrotoluene (2,4-DNT) as a common industrial waste has been massively discharged into the environment with industrial wastewater. Due to its refractory degradation, high toxicity, and bioaccumulation, 2,4-DNT pollution has become increasingly serious. Compared with the currently available physical and chemical methods, in situ bioremediation is considered as an economical and environmentally friendly approach to remove toxic compounds from contaminated environment. In this study, we relocated a complete degradation pathway of 2,4-DNT into Escherichia coli to degrade 2,4-DNT completely. Eight genes from Burkholderia sp. strain were re-synthesized by PCR-based two-step DNA synthesis method and introduced into E. coli. Degradation experiments revealed that the transformant was able to degrade 2,4-DNT completely in 12 h when the 2,4-DNT concentration reached 3 mM. The organic acids in the tricarboxylic acid cycle were detected to prove the degradation of 2,4-DNT through the artificial degradation pathway. The results proved that 2,4-DNT could be completely degraded by the engineered bacteria. In this study, the complete degradation pathway of 2,4-DNT was constructed in E. coli for the first time using synthetic biology techniques. This research provides theoretical and experimental bases for the actual treatment of 2,4-DNT, and lays a technical foundation for the bioremediation of organic pollutants.

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