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1.
World J Gastroenterol ; 30(9): 1143-1153, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38577185

RESUMO

BACKGROUND: Endoscopic full-thickness resection (EFTR) of gastric submucosal tumors (SMTs) is safe and effective; however, postoperative wound management is equally important. Literature on suturing following EFTR for large (≥ 3 cm) SMTs is scarce and limited. AIM: To evaluate the efficacy and clinical value of double-nylon purse-string suture in closing postoperative wounds following EFTR of large (≥ 3 cm) SMTs. METHODS: We retrospectively analyzed the data of 85 patients with gastric SMTs in the fundus of the stomach or in the lesser curvature of the gastric body whose wounds were treated with double-nylon purse-string sutures after successful tumor resection at the Endoscopy Center of Renmin Hospital of Wuhan University. The operative, postoperative, and follow-up conditions of the patients were evaluated. RESULTS: All tumors were completely resected using EFTR. 36 (42.35%) patients had tumors located in the fundus of the stomach, and 49 (57.65%) had tumors located in the body of the stomach. All patients underwent suturing with double-nylon sutures after EFTR without laparoscopic assistance or further surgical treatment. Postoperative fever and stomach pain were reported in 13 (15.29%) and 14 (16.47%) patients, respectively. No serious adverse events occurred during the intraoperative or postoperative periods. A postoperative review of all patients revealed no residual or recurrent lesions. CONCLUSION: Double-nylon purse-string sutures can be used to successfully close wounds that cannot be completely closed with a single nylon suture, especially for large (≥ 3 cm) EFTR wounds in SMTs.


Assuntos
Ressecção Endoscópica de Mucosa , Neoplasias Gástricas , Humanos , Nylons , Gastroscopia/efeitos adversos , Estudos Retrospectivos , Neoplasias Gástricas/patologia , Suturas , Resultado do Tratamento
2.
Int J Ophthalmol ; 17(4): 646-652, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38638261

RESUMO

AIM: To evaluate the effect of bone morphogenetic protein-6 (BMP-6) on transforming growth factor (TGF)-ß2-induced epithelial-mesenchymal transition (EMT) in retinal pigment epithelium (RPE). METHODS: Adult retinal pigment epithelial cell line (ARPE-19) were randomly divided into control, TGF-ß2 (5 µg/L), and BMP-6 small interfering RNA (siRNA) group. The cell morphology was observed by microscopy, and the cell migration ability were detected by Transwell chamber. The EMT-related indexes and BMP-6 protein levels were detected by Western blotting. Furthermore, a BMP-6 overexpression plasmid was constructed and RPE cells were divided into the control group, TGF-ß2+empty plasmid group, BMP-6 overexpression group, and TGF-ß2+BMP-6 overexpression group. The EMT-related indexes and extracellular regulated protein kinases (ERK) protein levels were detected. RESULTS: Compared with the control group, the migration of RPE cells in the TGF-ß2 group was significantly enhanced. TGF-ß2 increased the protein expression levels of α-smooth muscle actin (α-SMA), fibronectin and vimentin but significantly decreased the protein levels of E-cadherin and BMP-6 (P<0.05) in RPE. Similarly, the migration of RPE cells in the BMP-6 siRNA group was also significantly enhanced. BMP-6 siRNA increased the protein expression levels of α-SMA, fibronectin and vimentin but significantly decreased the protein expression levels of E-cadherin (P<0.05). Overexpression of BMP-6 inhibited the migration of RPE cells induced by TGF-ß2 and prevented TGF-ß2 from affecting EMT-related biomarkers (P<0.05). CONCLUSION: BMP-6 prevents the EMT in RPE cells induced by TGF-ß2, which may provide a theoretical basis for the prevention and treatment of proliferative vitreoretinopathy.

3.
J Ophthalmol ; 2024: 3270197, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38495222

RESUMO

This study describes a pars plana incision surgical technique combined with 23 or 25-gauge vitrectomy in the management of intraocular foreign bodies (IOFBs) and to assess its anatomical and functional results. Sixteen patients with ocular trauma complicated with IOFB were enrolled in our study. The mean preoperative visual acuity was 2.01 ± 0.55 LogMAR, and the mean postoperative visual acuity at the final visit was improved to 0.91 ± 0.58 LogMAR (p < 0.001). Until the last follow-up, all IOFBs were successfully removed and anatomic success was obtained. Complications, such as endophthalmitis, silicone oil-dependent, and ocular hypotonia, were not observed. Microsurgical vitrectomy with modified pars plana incision is a safe and effective procedure in the treatment of retained IOFB, especially associated with transparent lens and posterior segment injury.

4.
Int J Biol Macromol ; 264(Pt 2): 130705, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38458300

RESUMO

The mitochondria are known to exert significant influence on various aspects of cancer cell physiology. The suppression of mitochondrial function represents a novel avenue for the advancement of anti-cancer pharmaceuticals. The heat shock protein HSP90 functions as a versatile regulator of mitochondrial metabolism in cancer cells, rendering as a promising target for anticancer interventions. In this work, a novel acid polysaccharide named as XQZ3 was extracted from Chlorella pyrenoidosa and purified by DEAE-cellulose and gel-filtration chromatography. The structural characteristic of XQZ3 was evaluated by monosaccharides composition, methylation analysis, TEM, FT-IR, and 2D-NMR. It was found that XQZ3 with a molecular weight of 29.13 kDa was a complex branched polysaccharide with a backbone mainly composed of galactose and mannose. It exhibited good antitumor activity in vitro and in vivo by patient-derived 3D organoid models and patient-derived xenografts models. The mechanistic investigations revealed that XQZ3 specifically interacted with HSP90, impeding the activation of the HSP90/AKT/mTOR signaling cascade. This, in turn, led to the induction of mitochondrial dysfunction, autophagy, and apoptosis, ultimately resulting in the demise of cancer cells due to nutrient deprivation. This study offers a comprehensive theoretical foundation for the advancement of XQZ3, a novel polysaccharide inhibitor targeting HSP90, with potential as an effective therapeutic agent against cancer.


Assuntos
Chlorella , Neoplasias , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Chlorella/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Transdução de Sinais , Proteínas de Choque Térmico HSP90/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Apoptose , Metabolismo Energético , Mitocôndrias/metabolismo , Polissacarídeos/farmacologia , Polissacarídeos/metabolismo
5.
Ecotoxicol Environ Saf ; 274: 116215, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38489902

RESUMO

Nicotine exposure from smoking constitutes a significant global public health concern. Furthermore, smoking represents a pivotal risk factor for head and neck squamous cell carcinoma (HNSCC). However, the influence of nicotine on HNSCC remains relatively underexplored. Our aim was to unravel the molecular mechanisms that underlie the effect of nicotine on the metastatic cascade of HNSCC. In this study, we discovered a significant association between smoking and HNSCC metastasis and prognosis. Nicotine significantly enhanced HNSCC cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) in vitro. Analysis of TCGA-HNSCC and FDEENT-HNSCC cohorts revealed reduced miR-375-3p levels in HNSCC tumor tissues, particularly among current smokers. Additionally, miR-375-3p level was strongly correlated with both lymph node metastasis and tumor stage. By downregulating miR-375-3p, nicotine promotes HNSCC cell metastasis in vitro and hematogenous metastatic capacity in vivo. Utilizing transcriptomic sequencing, molecular docking, dual-luciferase reporter assay, and fluorescence in situ hybridization (FISH), we demonstrated that miR-375-3p specifically binds to 3' untranslated region (3'UTR) of NTRK2 mRNA. Thus, this study uncovers a novel nicotine-induced mechanism involving miR-375-3p-mediated NTRK2 targeting, which promotes HNSCC metastasis. These findings have implications for improving the prognosis of patients with HNSCC, especially in smokers.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , MicroRNAs , Receptores de Aminoácido , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Nicotina/toxicidade , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Simulação de Acoplamento Molecular , Hibridização in Situ Fluorescente , Neoplasias de Cabeça e Pescoço/genética , MicroRNAs/genética , Células Epiteliais/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Proliferação de Células
6.
Carbohydr Polym ; 332: 121889, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38431406

RESUMO

Metabolic alterations within mitochondria, encompassing processes such as autophagy and energy metabolism, play a pivotal role in facilitating the swift proliferation, invasion, and metastasis of cancer cells. Despite this, there is a scarcity of currently available medications with proven anticancer efficacy through the modulation of mitochondrial dysfunction in a clinical setting. Here, we introduce the structural characteristics of RN0D, a galactoglucan isolated and purified from Panax notoginseng flowers, mainly composed of ß-1,4-galactan and ß-1,3/1,6-glucan. RN0D demonstrates the capacity to induce mitochondrial impairment in cancer cells, leading to the accumulation of reactive oxygen species, initiation of mitophagy, and reduction in both mitochondrial number and size. This sequence of events ultimately results in the inhibition of mitochondrial and glycolytic bioenergetics, culminating in the demise of cancer cells due to adenosine triphosphate (ATP) deprivation. Notably, the observed bioactivity is attributed to RN0D's direct targeting of Galectin-3, as affirmed by surface plasmon resonance studies. Furthermore, RN0D is identified as an activator of the PTEN-induced kinase 1 (PINK1)/Parkin pathway, ultimately instigating cytotoxic mitophagy in tumor cells. This comprehensive study substantiates the rationale for advancing RN0D as a potentially efficacious anticancer therapeutic.


Assuntos
Neoplasias , Panax notoginseng , Polissacarídeos Bacterianos , Humanos , Mitofagia , Galactanos , Glucanos , Morte Celular , Ubiquitina-Proteína Ligases/metabolismo , Proteínas Quinases/metabolismo
7.
Front Aging Neurosci ; 16: 1356791, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38450384

RESUMO

Introduction: Estradiol is a sex steroid hormone, which has been implicated in the pathogenesis of Alzheimer's disease and cognitive impairment. This cross-sectional study aimed to examine the relationship between serum estradiol levels and cognitive performance in older American women. Methods: Data were obtained from the National Health and Nutrition Examination Survey 2013-2014. A total of 731 women aged ≥60 years who met the inclusion criteria were included in this study. Serum estradiol levels were measured using the isotope dilution liquid chromatography tandem mass spectrometry (ID-LC-MS/MS) method developed by the Centers for Disease Control and Prevention for routine analysis. All measured serum levels were further divided into three parts: T1, <3.68 pg./mL; T2, 3.68-7.49 pg./mL; T3, >7.49 pg./mL, and analyzed. Participants' cognitive abilities were tested using the Vocabulary Learning Subtest (CERAD), Animal Fluency Test (AFS), and digital symbol substitution test (DSST). Scores for each test were calculated based on the sample mean and standard deviation (SD). To examine the relationship between serum estradiol level tertiles and cognitive scores, multiple linear regression models were developed, controlling for race/ethnicity, education level, hypertension, diabetes, and insomnia. Results: The mean age of the participants was 69.57 ± 6.68 years. The non-Hispanic whites were 78.95%, and those who had completed at least some college-level education were 60.62%. The mean BMI of the participants was 29.30 ± 6.79, and 10.85% had a history of smoking. Further, 73.41% did not have a history of alcohol consumption, and 63.03% had hypertension (63.03%). In addition, 81.81 and 88.3% did not have a history of diabetes mellitus and did not have sleep disorders, respectively. The mean serum estradiol level was 8.48 ± 0.77 pg./mL. Multivariate linear regression of the reference group consisting of participants in tertiles of serum estradiol levels revealed that one unit increase in serum estradiol levels increased DSST scores by 0.61 (0.87, 6.34) in the T3 group. However, no significant correlation was found in the CERAD and AFS tests. Conclusion: Participants with higher estradiol levels had higher DSST scores and better processing speed, sustained attention, and working memory, suggesting that serum estradiol may serve as a biomarker for cognitive decline in older women.

8.
Cell Rep Med ; 5(2): 101416, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38350451

RESUMO

Peripheral T cell lymphoma (PTCL) is a heterogeneous group of non-Hodgkin's lymphomas varying in clinical, phenotypic, and genetic features. The molecular pathogenesis and the role of the tumor microenvironment in PTCL are poorly understood, with limited biomarkers available for genetic subtyping and targeted therapies. Through an integrated genomic and transcriptomic study of 221 PTCL patients, we delineate the genetic landscape of PTCL, enabling molecular and microenvironment classification. According to the mutational status of RHOA, TET2, histone-modifying, and immune-related genes, PTCL is divided into 4 molecular subtypes with discrete patterns of gene expression, biological aberrations, and vulnerabilities to targeted agents. We also perform an unsupervised clustering on the microenvironment transcriptional signatures and categorize PTCL into 4 lymphoma microenvironment subtypes based on characteristic activation of oncogenic pathways and composition of immune communities. Our findings highlight the potential clinical rationale of future precision medicine strategies that target both molecular and microenvironment alterations in PTCL.


Assuntos
Linfoma de Células T Periférico , Humanos , Linfoma de Células T Periférico/genética , Linfoma de Células T Periférico/metabolismo , Perfilação da Expressão Gênica , Genômica , Mutação , Microambiente Tumoral/genética
9.
Int J Pharm ; 655: 123848, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38316317

RESUMO

Surface tension is a crucial functional indicator for various classes of pharmaceutical excipients, as highlighted in both the Pharmacopoeia of the People's Republic of China (ChP) < 9601 Guidelines for Functionality-related Characteristics of Pharmaceutical Excipients > and the United States Pharmacopoeia (USP) < 1059 Excipient Performance >. However, there are few systematic studies on surface tension measurement of pharmaceutical excipients, resulting in a lack of stable parameter support in practical applications. In this study, we aim to fill this gap by exploring three different methods for measuring surface tension. These methods were carefully developed taking into account the actual measurement process and statistical theory, thus ensuring their applicability and reliability. Through comparative analyses, we have identified the most suitable measurement methods for different classes of pharmaceutical excipients. In addition, this paper describes the surface adsorption behavior of various excipients. Therefore, this study provides valuable guidance for the determination of surface tension and the study of surface adsorption behavior, which lays the foundation for further comprehensive research in the field of surface tension of pharmaceutical excipients and the improvement of general pharmacopoeia specification.


Assuntos
Química Farmacêutica , Excipientes , Humanos , Tensão Superficial , Reprodutibilidade dos Testes
11.
Mini Rev Med Chem ; 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38275028

RESUMO

Medicinal insects play an important role in the treatment of refractory diseases due to their unique and rich pharmacological activities. However, compared to plants, microorganisms, and marine organisms, medicinal insects have been largely ignored. Some small molecules isolated from insects are known to have defensive effects, but their majority roles remain unknown. In-depth research on the small molecules of medicinal insects has been conducted in recent years. Then alkaloids, dopamine derivatives, nucleoside derivatives, and other components are obtained. Among them, dopamine derivatives are a unique class of components from medicinal insects. Thus, we present a comprehensive overview of chemical structures and biological activities of dopamine derivatives from some medicinal insects, which will bring more attention to other researchers for further chemical and biological investigations on the unique dopamine derivatives as well as medicinal insects.

12.
Cell Death Dis ; 15(1): 44, 2024 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-38218970

RESUMO

A hallmark of tumor cells, including bladder cancer (BLCA) cells, is metabolic reprogramming toward aerobic glycolysis (Warburg effect). The classical oncogene MYC, which is crucial in regulating glycolysis, is amplified and activated in BLCA. However, direct targeting of the c-Myc oncoprotein, which regulates glycolytic metabolism, presents great challenges and necessitates the discovery of a more clarified regulatory mechanism to develop selective targeted therapy. In this study, a siRNA library targeting deubiquitinases identified a candidate enzyme named USP43, which may regulate glycolytic metabolism and c-Myc transcriptional activity. Further investigation using functional assays and molecular studies revealed a USP43/c-Myc positive feedback loop that contributes to the progression of BLCA. Moreover, USP43 stabilizes c-Myc by deubiquitinating c-Myc at K148 and K289 primarily through deubiquitinase activity. Additionally, upregulation of USP43 protein in BLCA increased the chance of interaction with c-Myc and interfered with FBXW7 access and degradation of c-Myc. These findings suggest that USP43 is a potential therapeutic target for indirectly targeting glycolytic metabolism and the c-Myc oncoprotein consequently enhancing the efficacy of bladder cancer treatment.


Assuntos
Proteínas Proto-Oncogênicas c-myc , Neoplasias da Bexiga Urinária , Humanos , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Glicólise/fisiologia , RNA Interferente Pequeno/metabolismo , Neoplasias da Bexiga Urinária/genética , Linhagem Celular Tumoral , Proliferação de Células
13.
Chem Biol Drug Des ; 103(1): e14358, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37749299

RESUMO

Parkinson's disease (PD) is the commonest neurodegenerative disorder. It reduces motor and cognitive function in patients. Vinpocetine (Vinp) has the effects of anti-inflammatory and antioxidant, and could improve cognitive function in patients. This study was aimed to investigating the therapeutic effects of Vinp on dyskinesia in a 6-Hydroxydopamine hydrobromide (6-OHDA)-induced PD rat model. We constructed a PD rat model by injecting 6-OHDA, and intervened with Vinp for 7 days. The motor function of the rats was evaluated by an open-field test and rotation test. Besides, H&E staining was applied to observe the changes of dopaminergic neurons in the striatum. The levels of superoxide dismutase (SOD) and malondialdehyde (MDA) in the rat striatum were detected. We assessed the impact of Vinp on α-synuclein (α-Syn) and Wnt/ß-catenin signaling pathway-related molecules by western blot and qRT-PCR. Rats in the PD group showed reduced horizontal movement frequency and number of squares crossed, increased contact time and rotation frequency, and reduced number of dopaminergic neurons accompanied by severe morphological damage. Vinp treatment increased the horizontal movement frequency and number of squares crossed, reduced the contact time, and rotation frequency in PD rats. Also, Vinp downregulated α-Syn protein expression and MDA level, while upregulated SOD activity in the striatum of PD rats. Furthermore, Vinp treatment activated the Wnt/ß-catenin signaling pathway in the striatum of PD rats. In conclusion, Vinp improved the dyskinesia in 6-OHDA-induced PD rats by alleviating oxidative stress, and these effects may be associated with activating the Wnt/ß-catenin signaling pathway.


Assuntos
Discinesias , Doença de Parkinson , Alcaloides de Vinca , Humanos , Ratos , Animais , Doença de Parkinson/tratamento farmacológico , Via de Sinalização Wnt/fisiologia , Oxidopamina/farmacologia , Oxidopamina/uso terapêutico , Estresse Oxidativo , Superóxido Dismutase/metabolismo , Modelos Animais de Doenças
14.
Front Public Health ; 11: 1233414, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38045959

RESUMO

Background: The deluge of COVID-19 misinformation makes people confused, and acting on such misinformation can kill, leading to the tragic outcome of death. This makes it necessary to identify significant factors associated with college students' susceptibility. Objective: This descriptive study sought to ascertain factors significantly associated with college students' susceptibility to online COVID-19 misinformation. Methods: To assess college students' susceptibility to COVID-19 misinformation, we first chose as independent variables some demographic information, some well-developed, validated literacy tools, and the Patient Health Questionnaire-9 Items. Second, we selected as the dependent variable COVID-19 myths from some authoritative, official websites. Third, we integrated the independent and dependent variables into an online questionnaire. Fourth, we recruited students from Nantong University in China to participate in an online questionnaire survey. Finally, based on the data collected, we conducted quantitative and qualitative analyses to relate the independent variables to the dependent variable. Results: Five hundred forty-six students participated in the survey voluntarily, and all questionnaires they answered were valid. The participants had an average of 2.32 (SD = 0.99) years of higher education. They have a mean age of 20.44 (SD = 1.52) years. 434 (79.5%) of the 546 participants were females. The frequency of their Internet use averaged 3.91 (SD = 0.41), indicating that they logged onto the Internet almost every day. Their self-reported Internet skill was rated 3.79 (SD = 1.07), indicating that the participants rated their Internet skills as basically "good." The mean scores of the sub-constructs in the AAHLS were 6.14 (SD = 1.37) for functional health literacy, 5.10 (SD = 1.65) for communicative health literacy, and 11.13 (SD = 2.65) for critical health literacy. These mean scores indicated that the participants needed help to read health-related materials "sometimes," the frequency that they knew how to communicate effectively with professional health providers was between "often" and "sometimes," and the frequency that they were critical about health information was between "often" and "sometimes," respectively. The sum of their scores for eHealth literacy averaged 28.29 (SD = 5.31), showing that they had a relatively high eHealth literacy level. The mean score for each question in the GHNT was determined at 1.31 (SD = 0.46), 1.36 (SD = 0.48), 1.41 (SD = 0.49), 1.77 (SD = 0.42), 1.51 (SD = 0.50), and 1.54 (SD = 0.50), respectively. These mean scores showed that a high percentage of the participants answered the 6 questions wrongly, especially Questions 4-6. Similarly, participants performed unsatisfactorily in answering the 3 questions in the CRT, with a mean score of 1.75 (SD = 0.43), 1.55 (SD = 0.50), and 1.59 (SD = 0.49) for each question, respectively. In the PHQ-9, the participants reported that they never felt depressed or felt depressed only for 1-3 days in the past week. The mean score for myths 1-6 and 9-10 ranged from 1.15 (SD = 0.36) to 1.29 (SD = 0.46). This meant that the participants rated these myths false. However, most of the participants rated myths 7-8 true (1.54, SD = 0.50; 1.49, SD = 0.50), showing that they were highly susceptible to these 2 pieces of misinformation. Through data analysis via Logistic Regression (forward stepwise), we found that (1) at an average threshold of 0.5, Internet use frequency, functional health literacy, general health numeracy, reflective thinking tendency, and depression severity were significant predictors of susceptibility to misinformation for both male and female students, (2) at a higher threshold of 0.8, aggregated general health numeracy scores and functional health literacy scores, as well as depression severity were predictors of susceptibility to misinformation for both male and female students, (3) functional health literacy, general health literacy, and depression predicted resistance to misinformation for female students, and (4) internet use frequency and self-reported digital health literacy predicted resistance to misinformation for male students. Conclusion: We revealed the complexity, dynamics, and differences in age, gender, education, Internet exposure, communicative health literacy, and cognitive skills concerning college students' susceptibility to online COVID-19 misinformation. Hopefully, this study can provide valuable implications for counteracting COVID-19 misinformation among Chinese college students.


Assuntos
COVID-19 , Letramento em Saúde , Humanos , Masculino , Feminino , Adulto Jovem , Adulto , COVID-19/epidemiologia , Inquéritos e Questionários , Autorrelato , Estudantes/psicologia
15.
Ying Yong Sheng Tai Xue Bao ; 34(9): 2391-2397, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37899104

RESUMO

Urease inhibitors and nitrification inhibitors can enhance nitrogen (N) fertilizer utilization efficiency and reducing N losses through regulating urea-N transformation. Common urease or nitrification inhibitors, however, are predominantly chemically synthesized and high-cost. Furthermore, their inhibitory effects are mediated by soil pro-perties, climatic conditions, and crop systems. In this study, we conducted a field experiment using natural synergists humic acid/zeolite, along with chemical nitrification inhibitor dicyandiamide (DCD) and their combination to elucidate the impacts of natural synergists combined with chemical inhibitors on annual yield, nitrogen utilization efficiency, soil nitrate-N accumulation, and nitrogen balance within the wheat/maize rotation system. The treatments included no nitrogen fertilizer application (CK), single application of urea (N), urea +DCD (ND), urea + humic acid (NH), urea + zeolite (NP), urea + urease inhibitor N-butylthiophosphoric triamide + DCD (NUD), urea + humic acid + DCD (NHD), and urea + zeolite + DCD (NPD). The results showed that, compared to the treatments NH and NP, the integration of humic acid or zeolite with DCD (NHD and NPD) significantly increased maize yield (11268 and 11397 kg·hm-2) and total annual yield (20494 and 20582 kg·hm-2), which were comparable to those of combined chemical urease and nitrification inhibitors (NUD). The NHD and NPD treatments had higher nitrogen utilization efficiency and lower soil nitrate-N accumulation in 80-100 cm soil layer across all seasons relative to the N treatment, which had no significant difference compared to the NUD treatment. Furthermore, a decline in soil nitrogen surplus by 10.7% and 13.9% was observed when comparing the NHD and NPD treatments with the NH and NP treatments, respectively. These findings suggested that combined humic acid or zeolite and chemical nitrification inhibitors could effectively enhance crop yield and N utilization efficiency and meet the requirements of the green and environmental preservation of modern agriculture.


Assuntos
Zea mays , Zeolitas , Triticum , Substâncias Húmicas , Fertilizantes/análise , Nitratos/farmacologia , Urease , Solo , Agricultura/métodos , Ureia/farmacologia , Nitrogênio/análise , Nitrificação
16.
PLoS One ; 18(10): e0292007, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37847727

RESUMO

The Silicon Valley Bank crisis that occurred in March 2023 highlights the importance of studying the risk transmission mechanism underlying monetary policy. To explore this mechanism in the monetary and financial services sector from the perspective of asset-liability management, the relationships between asset- and liability-side risks and the corresponding action direction of those risks were empirically studied based on the risk-taking channel theory of monetary policy using publicly available information on 176 Chinese monetary and financial services companies covering the period of 2000 to 2022. The analysis shows that asset-side risks are transmitted through monetary policy as liability-side risks in the monetary and financial service sectors. If the liability side passively takes on these risks, the action direction of monetary policy to asset-side risks is determined; when the liability side actively takes on these risks, monetary policy exerts opposite effects on both types of risks. This conclusion somewhat deepens our understanding of the risk transmission mechanism of monetary policy, which is helpful in better formulating and implementing monetary policy.


Assuntos
Meio Ambiente , Políticas
17.
Phys Chem Chem Phys ; 25(40): 27756-27765, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37814579

RESUMO

The substitution of oxygen with chalcogen in carbonyl group(s) of canonical nucleobases gives an impressive triplet generation, enabling their promising applications in medicine and other emerging techniques. The excited-state relaxation S2(ππ*) → S1(nπ*) → T1(ππ*) has been considered the preferred path for triplet generation in these nucleobase derivatives. Here, we demonstrate enhanced quantum efficiency of direct intersystem crossing from S2 to triplet manifold upon substitution with heavier chalcogen elements. The excited-state relaxation dynamics of sulfur/selenium substituted guanines in a vacuum is investigated using a combination of static quantum chemical calculations and on-the-fly excited-state molecular dynamics simulations. We find that in sulfur-substitution the S2 state predominantly decays to the S1 state, while upon selenium-substitution the S2 state deactivation leads to simultaneous population of the S1 and T2,3 states in the same time scale and multi-state quasi-degeneracy region S2/S1/T2,3. Interestingly, the ultrafast deactivation of the spectroscopic S3 state of both studied molecules to the S1 state occurs through a successive S3 → S2 → S1 path involving a multi-state quasi-degeneracy S3/S2/S1. The populated S1 and T2 states will cross the lowest triplet state, and the S1 → T intersystem crossing happens in a multi-state quasi-degeneracy region S1/T2,3/T1 and is accelerated by selenium-substitution. The present study reveals the influence of both the chalcogen substitution element and initial spectroscopic state on the excited-state relaxation mechanism of nucleobase photosensitizers and also highlights the important role of multi-state quasi-degeneracy in mediating the complex relaxation process. These theoretical results provide additional insights into the intrinsic photophysics of nucleobase-based photosensitizers and are helpful for designing novel photo-sensitizers for real applications.

18.
Sci Adv ; 9(37): eadh7820, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37703377

RESUMO

1,3-ß-Glucan serves as the primary component of the fungal cell wall and is produced by 1,3-ß-glucan synthase located in the plasma membrane. This synthase is a molecular target for antifungal drugs such as echinocandins and the triterpenoid ibrexafungerp. In this study, we present the cryo-electron microscopy structure of Saccharomyces cerevisiae 1,3-ß-glucan synthase (Fks1) at 2.47-Å resolution. The structure reveals a central catalytic region adopting a cellulose synthase fold with a cytosolic conserved GT-A-type glycosyltransferase domain and a closed transmembrane channel responsible for glucan transportation. Two extracellular disulfide bonds are found to be crucial for Fks1 enzymatic activity. Through structural comparative analysis with cellulose synthases and structure-guided mutagenesis studies, we gain previously unknown insights into the molecular mechanisms of fungal 1,3-ß-glucan synthase.


Assuntos
beta-Glucanas , Microscopia Crioeletrônica , Antifúngicos , Catálise
19.
Mar Pollut Bull ; 196: 115557, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37776739

RESUMO

Oil spilled in marine environments can settle to the seafloor through aggregation and sedimentation processes. This has been predicted to be especially relevant in the Arctic due to plankton blooms initiated by melting sea ice. These conditions exist in the Kivalliq region in Nunavut, Canada, where elevated shipping traffic has increased the risk of accidental spills. Experimental microcosms combining surface sediment and crude oil were incubated at 4 °C over 21 weeks to evaluate the biodegradation potential of seabed microbiomes. Sediments sampled near the communities of Arviat and Chesterfield Inlet were assessed for biodegradation capabilities by combining hydrocarbon geochemistry with 16S rRNA gene and metagenomic sequencing, revealing decreased microbial diversity but enrichment of oil-degrading taxa. Alkane and aromatic hydrocarbon losses corresponded to detection of genes and genomes that encode enzymes for aerobic biodegradation of these compounds, pointing to the utility of marine microbiome surveys for predicting the fate of oil released into Arctic marine environments.


Assuntos
Microbiota , Poluição por Petróleo , Petróleo , Petróleo/metabolismo , Nunavut , RNA Ribossômico 16S/genética , Hidrocarbonetos/metabolismo , Canadá , Biodegradação Ambiental
20.
JMIR Form Res ; 7: e43345, 2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37585255

RESUMO

BACKGROUND: Bladder cancer is a leading cause of death among Chinese male populations in recent years. The health locus of control construct can mediate health status and outcomes, and it has proven helpful in predicting and explaining specific health-related behaviors. However, it has never been used to investigate health beliefs about bladder cancer prevention and treatment. OBJECTIVE: This study aimed to classify male patients into different latent groups according to their beliefs about bladder cancer prevention and treatment and to identify associated factors to provide implications for the delivery of tailored education and interventions and the administration of targeted prevention and treatment. METHODS: First, we designed a four-section questionnaire to solicit data: section 1-age, gender, and education; section 2-the communicative subscale of the All Aspects of Health Literacy Scale; section 3-the eHealth Literacy Scale; and section 4-health beliefs about bladder cancer prevention and treatment measured by the Multidimensional Health Locus of Control Scale Form C. We hypothesized that the participants' health beliefs about bladder cancer prevention and treatment measured in section 4 could be closely associated with information collected through sections 1 to 3. We recruited 718 Chinese male patients from Qilu Hospital of Shandong University, China, and invited them to participate in a web-based questionnaire survey. Finally, we used latent class analysis to identify subgroups of men based on their categorical responses to the items on the Multidimensional Health Locus of Control Scale Form C and ascertained factors contributing to the low self-efficacy group identified. RESULTS: We identified 2 subgroups defined as low and moderate self-efficacy groups representing 75.8% (544/718) and 24.2% (174/718) of the total sample, respectively. Men in the low self-efficacy cluster (cluster 1: 544/718, 75.8%) were less likely to believe in their own capability or doctors' advice to achieve optimal outcomes in bladder cancer prevention and treatment. Men in the moderate self-efficacy cluster (cluster 2: 174/718, 24.2%) had distinct psychological traits. They had stronger beliefs in their own capability to manage their health with regard to bladder cancer prevention and treatment and moderate to high levels of trust in health and medical professionals and their advice to achieve better prevention and treatment outcomes. Four factors contributing to low self-efficacy were identified, including limited education (Year 6 to Year 12), aged ≥44 years, limited communicative health literacy, and limited digital health literacy. CONCLUSIONS: This was the first study investigating beliefs about bladder cancer prevention and treatment among Chinese male patients. Given that bladder cancer represents a leading cause of death among Chinese male populations in recent years, the low self-efficacy cluster and associated contributing factors identified in this study can provide implications for clinical practice, health education, medical research, and health policy-making.

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