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1.
Toxics ; 12(4)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38668504

RESUMO

Dihydroxylated polybrominated diphenyl ethers (DiOH-PBDEs) could be the metabolites of PBDEs of some organisms or the natural products of certain marine bacteria and algae. OH-PBDEs may demonstrate binding affinity to thyroid hormone receptors (TRs) and can disrupt the functioning of the systems modulated by TRs. However, the thyroid hormone disruption mechanism of diOH-PBDEs remains elusive due to the absence of diOH-PBDEs standards. This investigation explores the potential disruptive effects of OH/diOH-PBDEs on thyroid hormones via competitive binding and coactivator recruitment with TRα and TRß. At levels of 5000 nM and 25,000 nM, 6-OH-BDE-47 demonstrated significant recruitment of steroid receptor coactivator (SRC), whereas none of the diOH-PBDEs exhibited SRC recruitment within the range of 0.32-25,000 nM. AutoDock CrankPep (ADCP) simulations suggest that the conformation of SRC and TR-ligand complexes, particularly their interaction with Helix 12, rather than binding affinity, plays a pivotal role in ligand agonistic activity. 6,6'-diOH-BDE-47 displayed antagonistic activity towards both TRα and TRß, while the antagonism of 3,5-diOH-BDE-100 for TRα and TRß was concentration-dependent. 3,5-diOH-BDE-17 and 3,5-diOH-BDE-51 exhibited no discernible agonistic or antagonistic activities. Molecular docking analysis revealed that the binding energy of 3,3',5-triiodo-L-thyronine (T3) surpassed that of OH/diOH-PBDEs. 3,5-diOH-BDE-100 exhibited the highest binding energy, whereas 6,6'-diOH-BDE-47 displayed the lowest. These findings suggest that the structural determinants influencing the agonistic and antagonistic activities of halogen phenols may be more intricate than previously proposed, involving factors beyond high-brominated PBDEs or hydroxyl group and bromine substitutions. It is likely that the agonistic or antagonistic propensities of OH/diOH-PBDEs are instigated by protein conformational changes rather than considerations of binding energy.

2.
J Hazard Mater ; 471: 134376, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38657503

RESUMO

Pig manure (PM) is a high concentration organic waste rich in sulfur, and its biofuel contains various sulfur-containing pollutants, which reduces the safety of the products. Supercritical water (SCW) can dissolve most organic matter, which is a technology worthy of further study. In order to reduce sulfur pollution in the process of PM resource utilization and better control the conversion path of sulfur, it is necessary to explore the migration mechanism of sulfur in the whole PM-SCW gasification process. The experimental results indicated that H2S was the only gaseous product. Only inorganic compounds (S2-, S2O32- and SO42-) were detected in the liquid. Sulfur in the solid mainly included thiol/thioether, thiophene and sulfone. The influence of different reaction conditions (temperature, residence time, PM concentration and catalysts) on sulfur migration was studied in a batch reactor. It was worth noting that the catalysts had a significant effect on H2S absorption. The lowest H2S yield was 3.2 * 10-4 mol/kg and more than 70% of the sulfur was distributed in the liquid under the condition of addition of K2CO3. While, the RTH2110 fixed most of the sulfur of PM (the maximum value reached 50.94%) in the solid. Thus, adding the catalysts flexibly can choose composition of the products. Furthermore, six possible pathways of sulfur migration in the solid were designed and the kinetic parameters were calculated by density functional theory (DFT). The results provided a basis for controlling sulfur in PM. Subsequently, the sulfur migration pathways during PM-SCW gasification process were comprehensively summarized through the combination of experiment and DFT. It provided a method for sulfur treatment in PM, which had guiding significance for the realization of pollution-free treatment of PM.

3.
Int Immunopharmacol ; 133: 112053, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38615380

RESUMO

Although PD-1 inhibitors have revolutionized the treatment paradigm of non-small cell lung cancer (NSCLC), their efficacy in treating NSCLC has remained unsatisfactory. Targeting cancer-associated fibroblasts (CAFs) is a potential approach for improving the immunotherapy response. Multitarget antiangiogenic tyrosine kinase receptor inhibitors (TKIs) can enhance the efficacy of PD-1 inhibitors in NSCLC patients. However, the effects and mechanisms of antiangiogenic TKIs on CAFs have not been elucidated. In this study, we first compared anlotinib with other antiangiogenic TKIs and confirmed the superior efficacy of anlotinib. Furthermore, we established NSCLC-associated CAF models and found that anlotinib impaired CAF viability and migration capacity and contributed to CAF apoptosis and cell cycle arrest in the G2/M phase. Moreover, anlotinib treatment attenuated the capacity of CAFs to recruit lung cancer cells and macrophages. Experiments in animal models suggested that anlotinib could enhance the efficacy of anti-PD1 therapy in NSCLC and affect CAF proliferation and apoptosis. Anlotinib increased the abundance of tumor-infiltrating CD8 + T cells, and PD-1 inhibitor-induced cytotoxicity to tumor cells was achieved through the transformation of the tumor microenvironment (TME) caused by anlotinib, which may partly explain the synergistic antitumor effect of anlotinib and PD-1 inhibitors. Mechanistically, anlotinib affects CAF apoptosis and cell viability at least in part by inhibiting the AKT pathway. In conclusion, our study suggested that anlotinib could regulate the TME, inhibit the AKT pathway and promote CAF apoptosis, providing new insights into the antitumor effect of anlotinib and improving the efficacy of immunotherapy.

4.
Fish Shellfish Immunol ; 149: 109561, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38636738

RESUMO

Toll-interacting protein (Tollip) serves as a crucial inhibitory factor in the modulation of Toll-like receptor (TLR)-mediated innate immunological responses. The structure and function of Tollip have been well documented in mammals, yet the information in teleost remained limited. This work employed in vitro overexpression and RNA interference in vivo and in vitro to comprehensively examine the regulatory effects of AjTollip on NF-κB and MAPK signaling pathways. The levels of p65, c-Fos, c-Jun, IL-1, IL-6, and TNF-α were dramatically reduced following overexpression of AjTollip, whereas knocking down AjTollip in vivo and in vitro enhanced those genes' expression. Protein molecular docking simulations showed AjTollip interacts with AjTLR2, AjIRAK4a, and AjIRAK4b. A better understanding of the transcriptional regulation of AjTollip is crucial to elucidating the role of Tollip in fish antibacterial response. Herein, we cloned and characterized a 2.2 kb AjTollip gene promoter sequence. The transcription factors GATA1 and Sp1 were determined to be associated with the activation of AjTollip expression by using promoter truncation and targeted mutagenesis techniques. Collectively, our results indicate that AjTollip suppresses the NF-κB and MAPK signaling pathways, leading to the decreased expression of the downstream inflammatory factors, and GATA1 and Sp1 play a vital role in regulating AjTollip expression.

5.
World J Gastroenterol ; 30(6): 542-555, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38463023

RESUMO

BACKGROUND: Lymphovascular invasion (LVI) and perineural invasion (PNI) are important prognostic factors for gastric cancer (GC) that indicate an increased risk of metastasis and poor outcomes. Accurate preoperative prediction of LVI/PNI status could help clinicians identify high-risk patients and guide treatment decisions. However, prior models using conventional computed tomography (CT) images to predict LVI or PNI separately have had limited accuracy. Spectral CT provides quantitative enhancement parameters that may better capture tumor invasion. We hypothesized that a predictive model combining clinical and spectral CT parameters would accurately preoperatively predict LVI/PNI status in GC patients. AIM: To develop and test a machine learning model that fuses spectral CT parameters and clinical indicators to predict LVI/PNI status accurately. METHODS: This study used a retrospective dataset involving 257 GC patients (training cohort, n = 172; validation cohort, n = 85). First, several clinical indicators, including serum tumor markers, CT-TN stages and CT-detected extramural vein invasion (CT-EMVI), were extracted, as were quantitative spectral CT parameters from the delineated tumor regions. Next, a two-step feature selection approach using correlation-based methods and information gain ranking inside a 10-fold cross-validation loop was utilized to select informative clinical and spectral CT parameters. A logistic regression (LR)-based nomogram model was subsequently constructed to predict LVI/PNI status, and its performance was evaluated using the area under the receiver operating characteristic curve (AUC). RESULTS: In both the training and validation cohorts, CT T3-4 stage, CT-N positive status, and CT-EMVI positive status are more prevalent in the LVI/PNI-positive group and these differences are statistically significant (P < 0.05). LR analysis of the training group showed preoperative CT-T stage, CT-EMVI, single-energy CT values of 70 keV of venous phase (VP-70 keV), and the ratio of standardized iodine concentration of equilibrium phase (EP-NIC) were independent influencing factors. The AUCs of VP-70 keV and EP-NIC were 0.888 and 0.824, respectively, which were slightly greater than those of CT-T and CT-EMVI (AUC = 0.793, 0.762). The nomogram combining CT-T stage, CT-EMVI, VP-70 keV and EP-NIC yielded AUCs of 0.918 (0.866-0.954) and 0.874 (0.784-0.936) in the training and validation cohorts, which are significantly higher than using each of single independent factors (P < 0.05). CONCLUSION: The study found that using portal venous and EP spectral CT parameters allows effective preoperative detection of LVI/PNI in GC, with accuracy boosted by integrating clinical markers.


Assuntos
Neoplasias Gástricas , Humanos , Estudos Retrospectivos , Prognóstico , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/patologia , Tomografia Computadorizada por Raios X/métodos , Aprendizado de Máquina
6.
BMC Nurs ; 23(1): 211, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38539192

RESUMO

BACKGROUND: Transition shock occurs at a vulnerable time in newly graduated registered nurses' careers and has a clear impact on both newly graduated registered nurses' productivity and patient recovery outcomes. Identifying classification features of transition shock and targeting interventions to support newly graduated registered nurses is imperative. The study aimed to explore potential transition shock subgroups of newly graduated registered nurses and further explore the impact of population characteristics and two indices of health on transition shock. METHODS: A descriptive, cross-sectional design was conducted. An online questionnaire was sent via WeChat to newly graduated registered nurses who started work in 2021 at seven hospitals between August and November 2021, and 331 nurses filled out the questionnaire. Latent class analysis was used to identify the potential class of the transition shock of newly graduated registered nurses, and multinomial logistic regression analyses were used to determine the factors of potential classification. RESULTS: The study identified four classes of transition shock in newly graduated registered nurses, namely, "high transition shock", "physical fatigue-lack of knowledge", "development adaptation" and "low transition shock-worry" groups. Newly graduated registered nurses who urinated less than 4 times per day (OR = 0.051, 95% CI = 0.005-0.502) were likely to be in the "high transition shock" group. Newly graduated registered nurses who did not delay urination (OR = 4.267, 95% CI = 1.162-11.236) were more likely to belong to the "low transition shock-worry" group. Newly graduated registered nurses without sleep disturbance were more likely to be in the "physical fatigue - lack of knowledge" (OR = 3.109, 95% CI = 1.283-7.532), "development adaptation" (OR = 8.183, 95% CI = 2.447-27.066), and "low transition shock-worry" (OR = 8.749, 95% CI = 1.619-47.288) groups than in the 'high transition shock' group. CONCLUSIONS: This study highlights potential patterns of transition shock among newly graduated registered nurses. Two indices of health, namely, delayed urination and sleep disturbance, can predict the subgroups of newly graduated registered nurses with transition shock.

7.
Patient Prefer Adherence ; 18: 709-720, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38524198

RESUMO

Background: Colorectal, and gastric cancers have the second, and fourth mortality rates worldwide, respectively. Endoscopic screening is a crucial diagnostic tool for colorectal, and gastric cancers. Effective interventions can improve adherence to endoscopic screening in high-risk populations, which is important for cancer prevention and mortality reduction. This study aimed to identify interventions that could improve adherence to endoscopic screening for cancer in high-risk populations. Methods: Combination keywords including colorectal cancer, gastric cancer, screening adherence, and interventions were used to search for articles in PubMed, Web of Science, Cochrane Library, and MEDLINE Complete. The review methodology was guided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-SCR). Results: A total of 12 articles were included in this review: 9 randomized controlled trials(RCT) and 3 quasi-experimental studies(QEDs). Among the extracted studies, 11 were about colorectal cancer, and 1 was about gastric cancer. Most studies used lecture-based or Information Technology-based health education interventions. Narrative interventions have proven to be novel and effective approaches for promoting adherence to endoscopic screening. Health education interventions included cancer epidemiology, cancer risk factors, warning symptoms, and screening methods. Conclusion: All interventions involved were effective in increasing individual knowledge of cancer-related endoscopic screening, willingness to undergo screening, and screening behaviors. These findings provide a reference for designing endoscopy-related cancer screening interventions.

8.
Public Health Nurs ; 41(3): 476-486, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38468509

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is the sixth most common cancer worldwide and the third leading cause of cancer mortality. HCC has high morbidity, high mortality, and low survival rates. Screening is one of the most significant methods of lowering incidence and death while also increasing survival. OBJECTIVES: The aim of this study was to identify the facilitators and barriers to participation in HCC screening among high-risk populations. METHODS: A comprehensive and systematic search was undertaken in PubMed, Web of Science, MEDLINE, EMBACE, EBSCOhost and the Cochrane Library. A combination of synonyms of the keywords including HCC, screening, factors and adherence were used for searching. Studies addressing the facilitators and barriers to HCC screening compliance in at-risk individuals were included. Data were synthesized using Review Manager version 5.4. A random/fixed effects model meta-analysis was performed to estimate the pooled data and expressed with odds ratio (OR) and 95% confidence interval (CI). RESULTS: A total of seven articles met the inclusion criteria. Qualitative (n = 1) and quantitative (n = 6) studies using various types of surgery were conducted. The most commonly mentioned barriers were insufficient knowledge and awareness of HCC screening, unawareness of the necessity for early detection of HCC and lack of physician recommendation. A meta-analysis of seven studies showed that individuals with a family history of HCC increased screening uptake by nearly three times (OR: 2.69, 95% CI: 1.93, 3.75). Other most frequently reported facilitators include age, education level, and perceived risk et al. CONCLUSIONS: Many barriers to HCC screening were found. Meanwhile, this review points out that improving the awareness of high-risk populations toward HCC screening is expected to enhance compliance, thereby promoting early diagnosis of liver cancer, reducing mortality, and alleviating the burden of HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/patologia , Incidência
9.
Nurs Open ; 11(2): e2085, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38391107

RESUMO

AIM: A specific, valid and reliable measure is much needed to dynamically assess the recovery of symptoms in oesophagectomy patients. This study describes developing and validating the Convalescent Symptom Assessment Scale for oesophagectomy patients (CSAS_EC). DESIGN: An instrument development and cross-sectional validation study was conducted. METHODS: This study consists of two components: instrument development and psychometric tests. In instrument development, the literature review, qualitative interviews, Delphi method expert consultation and face validation were used to develop and refine scale content. In psychometric tests, the clinical test version scale was used to conduct a cross-sectional in the thoracic surgery department from 17 June to 20 November 2022. The Classical Test Theory and Multidimensional Item Response Theory (MIRT) analyses examined psychometric properties. RESULTS: In instrument development, literature review (n = 20), qualitative interviews (n = 21), expert consultation (n = 12) and pre-survey (n = 15) led to the development of the clinical test version scale. In psychometric tests, a total of 331 participants were enrolled. Confirmatory factor analysis and MIRT analysis verified that a model with 28 items in four dimensions was good. The four dimensions were early recovery symptoms, late recovery symptoms, persistent present symptoms and psychosocial symptoms. The Cronbach's α is 0.827. The validity and reliability were demonstrated to be acceptable. CONCLUSIONS: The CSAS_EC scale can be used as a tool to evaluate the recovery status of oesophagectomy patients.


Assuntos
Convalescença , Esofagectomia , Humanos , Estudos Transversais , Esofagectomia/efeitos adversos , Reprodutibilidade dos Testes , Avaliação de Sintomas
10.
Artigo em Inglês | MEDLINE | ID: mdl-38391023

RESUMO

OBJECTIVE: Immune-mediated necrotizing myopathy (IMNM) is pathologically characterized by diffuse myofiber necrosis and regeneration, myophagocytosis, and a sparse inflammatory infiltrate. The monocyte chemoattractant protein-1 (MCP-1) is a key chemokine that regulates monocyte/macrophage infiltration into injured tissues. The interleukin-6 (IL-6) signalling in the induction of MCP-1 expression has not been investigated in IMNM. METHODS: MCP-1 expression in muscle specimens was assessed using immunohistochemistry and real-time quantitative polymerase chain reaction (RT-qPCR). Levels of multiple serological cytokines were evaluated using the Meso Scale Discovery electrochemiluminescence system. Flow cytometry, RT-qPCR, enzyme-linked immunosorbent assay, western blot, dual-luciferase reporter assays, and chromatin immunoprecipitation-qPCR were performed to explore the effects of IL-6 signalling on MCP-1 production in human myoblasts. RESULTS: MCP-1 was scattered and was positively expressed within myofibers and a few inflammatory cells in the muscles of patients with IMNM. Sarcoplasmic MCP-1 expression significantly correlated with myonecrosis, myoregeneration, and inflammatory infiltration. Serum MCP-1, IL-6, and the soluble form of the IL-6 receptor (sIL-6R) were elevated in patients with IMNM compared with controls. Serological MCP-1 levels were significantly associated with serum IL-6 expression and clinical disease severity in IMNM patients. The IL-6/sIL-6R complex induced MCP-1 expression via the signal transducer and activator of transcription 3 (STAT3) pathway in human myoblasts. Mechanistically, phospho-STAT3 was enriched in the MCP-1 promoter region and promoted the transcription. CONCLUSION: IL-6 trans-signalling may contribute to the immunopathogenesis of IMNM by augmenting inflammation through regulation of MCP-1 expression in IMNM.

11.
Eur J Oncol Nurs ; 68: 102501, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38194901

RESUMO

PURPOSE: The objective of this randomized controlled trial was to examine the effectiveness of promoted resilience intervention to facilitate resilience, self-efficacy, coping mode, and social support for oesophageal cancer patients in rural China. METHODS: A two-arm, parallel design, single-blinded, randomized controlled trial was conducted in a comprehensive tertiary hospital in Anhui from August 2021 to September 2022. A total of 82 oesophageal cancer patients were assigned to two groups via blocked randomization. The intervention group (n = 41) received the Promoted Psychological Resilience Intervention based on survivors' experiences and the control group (n = 41) received routine care. Study data were collected using the sociodemographic information, Connor-Davidson Resilience Scale, Strategies Used by People to Promote Health, Medical Coping Modes Questionnaire, and Perceived Social Support Scale. RESULTS: The groups were well-balanced at baseline. Post-intervention and three months after intervention, the resilience, self-efficacy, acceptance-resignation, and social support were all significantly different in the intervention and control groups (p < 0.05 for each). The main effect of group, time, and the interaction between group and time was statistically significant in the scores of resilience, self-efficacy, acceptance-resignation, and social support, except for the factor of self-determination and friends support (p < 0.05 for each). CONCLUSIONS: This study demonstrated that an intervention program based on the experiences of long-term oesophageal cancer survivors can promote patients' resilience.


Assuntos
Neoplasias Esofágicas , Testes Psicológicos , Resiliência Psicológica , Humanos , Adaptação Psicológica , Promoção da Saúde , China
12.
Org Lett ; 26(4): 971-976, 2024 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-38265233

RESUMO

Cinnamoyl-containing nonribosomal peptides (CCNPs) constitute a unique family of actinobacterial secondary metabolites that display a broad spectrum of biological activities. Here, we present a genome mining approach targeting cyclase and is isomerase to discover new CCNPs, which led to the identification of 207 putative CCNP gene clusters from public bacterial genome databases. After strain prioritization, a novel class of CCNP-type glycopeptides named malacinnamycin was identified. A plausible biosynthetic pathway for malacinnamycin was deduced by bioinformatics analysis.


Assuntos
Biologia Computacional , Peptídeos , Vias Biossintéticas/genética , Genoma Bacteriano , Família Multigênica , Cinamatos/química
13.
Breast Cancer Res Treat ; 203(3): 543-551, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37897648

RESUMO

PURPOSE: Secretory breast carcinoma is a rare histological subtype of invasive breast cancer and considered with an indolent clinical behavior. This study was conducted to analyze the clinicopathological features of patients with secretory breast carcinoma (SBC), explore the outcome, and compare the prognostic difference with invasive ductal breast carcinoma (IDC). METHODS AND MATERIALS: Patients with SBC diagnosed between 2006 and 2017 from Fudan University Shanghai Cancer Center were included in the study, excluding patients with previous malignant tumor history and incomplete clinical data or follow-up records. Peculiar clinicopathological and immunohistochemical features of the cases were fully described. Clinical data of 4979 cases of IDC were also evaluated during this period. After propensity score matching, prognostic analysis of SBCs and IDCs was calculated by Kaplan-Meier method and landmark analysis method. RESULTS: The data of 52 patients diagnosed with SBC were identified from the pathological files. Among them, 47 patients were women, and 5 were men. The median age of the 52 SBCs was 46 years (mean, 48.1 years; range, 10-80 years). The tumor sizes ranged from 0.3 to 6.8 cm, with a mean of 3.5 cm. Eight patients (15.4%) had positive axillary lymph node involvement. The molecular classification was mostly triple-negative breast cancer (65.4%). Fluorescence in situ hybridization confirmed the presence of ETV6::NTRK3 rearrangement in 16 of 18 cases (88.9%). Furthermore, Kaplan-Meier survival analysis and landmark analysis demonstrated that there were no statistically significant differences in DFS and OS between SBC and IDC patients. CONCLUSION: Although SBCs are generally associated with a favorable prognosis, our work exhibited that the clinicopathological features of SBC were partly different from former understandings, indicating that therapeutic procedure should be prudent. Further studies are necessary to fully identify the clinical behavior and predictive markers to improve diagnosis and management in this unique subtype of breast cancer.


Assuntos
Neoplasias da Mama , Carcinoma Ductal de Mama , Carcinoma , Neoplasias de Mama Triplo Negativas , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Neoplasias da Mama/terapia , Carcinoma Ductal de Mama/patologia , Hibridização in Situ Fluorescente , China , Prognóstico , Neoplasias de Mama Triplo Negativas/patologia
14.
Angew Chem Int Ed Engl ; 63(10): e202314046, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38072825

RESUMO

Cyclic peptides with cyclophane linkers are an attractive compound type owing to the fine-tuned rigid three-dimensional structures and unusual biophysical features. Cytochrome P450 enzymes are capable of catalyzing not only the C-C and C-O oxidative coupling reactions found in vancomycin and other nonribosomal peptides (NRPs), but they also exhibit novel catalytic activities to generate cyclic ribosomally synthesized and post-translationally modified peptides (RiPPs) through cyclophane linkage. To discover more P450-modified multicyclic RiPPs, we set out to find cryptic and unknown P450-modified RiPP biosynthetic gene clusters (BGCs) through genome mining. Synergized bioinformatic analysis reveals that P450-modified RiPP BGCs are broadly distributed in bacteria and can be classified into 11 classes. Focusing on two classes of P450-modified RiPP BGCs where precursor peptides contain multiple conserved aromatic amino acid residues, we characterized 11 novel P450-modified multicyclic RiPPs with different cyclophane linkers through heterologous expression. Further mutation of the key ring-forming residues and combinatorial biosynthesis study revealed the order of bond formation and the specificity of P450s. This study reveals the functional diversity of P450 enzymes involved in the cyclophane-containing RiPPs and indicates that P450 enzymes are promising tools for rapidly obtaining structurally diverse cyclic peptide derivatives.


Assuntos
Produtos Biológicos , Peptídeos/química , Peptídeos Cíclicos/química , Biologia Computacional/métodos , Sistema Enzimático do Citocromo P-450/metabolismo , Processamento de Proteína Pós-Traducional , Produtos Biológicos/química
15.
Chemosphere ; 346: 140583, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37918539

RESUMO

Perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), as emerging endocrine-disrupting chemicals (EDCs), pose adverse effects on aquatic organisms. Conventional ecological risk assessment (ERA) not fully considering the mode of toxicity action of PFOS and PFOA, may result in an underestimation of risks and confuse decision-makers. In the study, we developed species sensitivity weighted distribution (SSWD) models based on adverse outcome pathway (AOP) networks for deriving predicted no-effect concentrations (PNECs). Three kinds of weighting criteria (intraspecies variation, trophic level abundance, and data quality) and weighted log-normal distribution methods were adopted. The developed models considered the inter/intraspecies variation and integrated nontraditional endpoints of endocrine-disrupting effects. The PNECs of endocrine disruption effects were derived as 2.52 µg/L (95% confidence intervals 0.667-9.85 µg/L) for PFOS and 18.7 µg/L (5.40-71.0 µg/L) for PFOA, which were more conservative than those derived from the SSD method and were comparable with the values in the literature based on the chronic toxicity data. For PFOS, the effect of growth and development was the most sensitive; however, for PFOA, the effect of reproduction was the most sensitive in the effects of growth and development, reproduction, biochemistry and genetics, and survival. The endocrine-disrupting effects of PFOS and PFOA are significant and need to be fully recognized in the ERA. This study provided an ERA framework that can improve the ecological relevance and reduce the uncertainty of PNECs of EDCs.


Assuntos
Rotas de Resultados Adversos , Ácidos Alcanossulfônicos , Disruptores Endócrinos , Fluorocarbonos , Fluorocarbonos/toxicidade , Fluorocarbonos/análise , Medição de Risco , Ácidos Alcanossulfônicos/toxicidade , Caprilatos/toxicidade , Disruptores Endócrinos/toxicidade
16.
J Am Chem Soc ; 145(50): 27325-27335, 2023 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-38069901

RESUMO

Cyclization of linear peptides is an effective strategy to convert flexible molecules into rigid compounds, which is of great significance for enhancing the peptide stability and bioactivity. Despite significant advances in the past few decades, Nature and chemists' ability to macrocyclize linear peptides is still quite limited. P450 enzymes have been reported to catalyze macrocyclization of peptides through cross-linkers between aromatic amino acids with only three examples. Herein, we developed an efficient workflow for the identification of P450-modified RiPPs in bacterial genomes, resulting in the discovery of a large number of P450-modified RiPP gene clusters. Combined with subsequent expression and structural characterization of the products, we have identified 11 novel P450-modified RiPPs with different cross-linking patterns from four distinct classes. Our results greatly expand the structural diversity of P450-modified RiPPs and provide new insights and enzymatic tools for the production of cyclic peptides.


Assuntos
Produtos Biológicos , Ribossomos , Ribossomos/metabolismo , Peptídeos/química , Peptídeos Cíclicos/química , Sistema Enzimático do Citocromo P-450/metabolismo , Processamento de Proteína Pós-Traducional , Produtos Biológicos/química
17.
Artigo em Inglês | MEDLINE | ID: mdl-38021354

RESUMO

Background: Helicobacter pylori (Hp) infection is highly prevalent globally and is predominantly managed by antibiotics. Recently, the anti-adhesive, antioxidant, antitoxin, immunomodulatory, anti-coagulant, and anti-infective activities of fucoidan, a polysaccharide extracted from brown seaweeds, have been widely studied, and the results showed promise. Fucoidan has the potential to be utilized in Hp eradication therapy. Our present clinical study was designed to evaluate the efficiency of Lewuyou®, a fucoidan plant drink (FPD) in eradicating Hp in humans. Methods: This multi-center, clinical study was conducted between October 2020 and July 2021. Hp infection was confirmed by urea breath test (UBT). A total of 122 patients with confirmed Hp infection were enrolled; after exclusion of incomplete data, 85 eligible patients (37 males and 48 females aged 20-81 years) were included in the final analysis. FPD (50 mL per vial) was orally administered twice daily for a 4-week cycle, and 41 patients completed an 8-week cycle. Results: No adverse event (AE) was reported in all 122 participants who had consumed FPD. The Hp eradication rate and clearance rate were 77.6% (66/85) and 20.0% (17/85), respectively, after 4 weeks of FPD consumption and 80.5% (33/41) and 26.8 (11/41) , respectively, after 8 weeks of consumption. Conclusions: The 4- and 8-week protocols of FPD consumption were safe and effective at reducing Hp load on the gastric mucosa, with Hp eradicated in the majority of participants.

18.
Angew Chem Int Ed Engl ; 62(47): e202312996, 2023 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-37804495

RESUMO

Phomactin diterpenoids possess a unique bicyclo[9.3.1]pentadecane skeleton with multiple oxidative modifications, and are good platelet-activating factor (PAF) antagonists that can inhibit PAF-induced platelet aggregation. In this study, we identified the gene cluster (phm) responsible for the biosynthesis of phomactins from a marine fungus, Phoma sp. ATCC 74077. Despite the complexity of their structures, phomactin biosynthesis only requires two enzymes: a type I diterpene cyclase PhmA and a P450 monooxygenase PhmC. PhmA was found to catalyze the formation of the phomactatriene, while PhmC sequentially catalyzes the oxidation of multiple sites, leading to the generation of structurally diverse phomactins. The rearrangement mechanism of the diterpene scaffold was investigated through isotope labeling experiments. Additionally, we obtained the crystal complex of PhmA with its substrate analogue FGGPP and elucidated the novel metal-ion-binding mode and enzymatic mechanism of PhmA through site-directed mutagenesis. This study provides the first insight into the biosynthesis of phomactins, laying the foundation for the efficient production of phomactin natural products using synthetic biology approaches.


Assuntos
Diterpenos , Fator de Ativação de Plaquetas , Fungos
19.
Orthop Surg ; 15(12): 3101-3107, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37817420

RESUMO

OBJECTIVE: The treatment of distal third humeral shaft fracture is difficult. Studies have shown that anterior minimally invasive plate has lower probability of complication and higher healing rate. However there is no applicable anatomical plate at present. This study is to investigate the clinical effect of intramedullary nail combined with anterior minimally invasive plate in the treatment of distal humeral shaft fractures. METHODS: The data of 83 patients with lower humerus shaft fracture treated from September 2015 to January 2020 were analyzed. According to different treatment methods, they were divided into two groups: 40 patients were treated with intramedullary nailing combined with minimally invasive anterior plate fixation (group A), and 43 patients were treated with double plate fixation through posterior approach (group B). General preoperative data, operative time, intraoperative blood loss, total incision length, fracture healing time, shoulder and elbow visual analogue scale (VAS) score, Constant-Murley shoulder function score, Mayo elbow function score, and complications were recorded and compared between the two groups. Two independent sample t-tests was used for follow-up, age, BMI, operation time, intraoperative bleeding, total incision length, fracture healing time, Constant-Murley score and Mayo score, and rank sum test was used for VAS score of shoulder and elbow. RESULTS: There was no significant difference in preoperative general data between the two groups (p > 0.05), indicating comparability. There were no significant differences in operation time, total incision length, fracture healing time, Constant-Murley shoulder function score at the last follow-up, Mayo elbow function score, and shoulder and elbow VAS pain score between 2 groups (p > 0.05). The amount of intraoperative blood loss in observation group was 76.98 ± 16.46, which was significantly less than that in control group, and the difference was statistically significant (p < 0.01). There were no radial nerve injury, musculocutaneous nerve injury, incision infection and fracture nonunion in the observation group. In the control group, four cases of iatrogenic radial nerve injury, three cases of incision infection and three cases of fracture nonunion were found. The complication rate was 23.3% (10/43). There was statistical difference in the incidence of complications between the two groups (p < 0.01). CONCLUSION: A humeral intramedullary nail combined with an anterior minimally invasive plate in the treatment of distal humeral shaft fracture has the advantages of less soft tissue damage, less blood transfusion, high fracture healing rate and low risk of iatrogenic radial nerve injury, which is an effective method for clinical treatment of this type of fracture.


Assuntos
Fixação Intramedular de Fraturas , Fraturas Distais do Úmero , Fraturas do Úmero , Humanos , Fraturas do Úmero/cirurgia , Perda Sanguínea Cirúrgica , Fixação Interna de Fraturas/métodos , Fixação Intramedular de Fraturas/métodos , Placas Ósseas , Úmero , Consolidação da Fratura , Infecção da Ferida Cirúrgica , Doença Iatrogênica , Resultado do Tratamento , Estudos Retrospectivos
20.
China CDC Wkly ; 5(34): 756-762, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37692760

RESUMO

Introduction: This study investigates the patterns of scarlet fever among Chinese children aged 0-9 years from 2010 to 2019. The objective is to provide insights that may inform potential adjustments to China's current prevention and control tactics for this illness. Methods: The present study utilized data on the occurrence of scarlet fever in children from 2010 to 2019, sourced from the National Notifiable Disease Reporting System database, managed by the Chinese Center for Disease Control and Prevention. This research implemented SAS9.4 software to construct trajectory models representing the temporal incidence of scarlet fever, accounting for key variables such as sex, geographic region, urban versus rural dwellings, and various age brackets. Results: From 2010 to 2019, a total of 554,695 scarlet fever cases were reported among children aged 0-9 years in the 31 mainland Chinese provincial-level administrative divisions, signifying a rate of 35.36 per 100,000 individuals. An inconsistent yet generally rising trend was observed, evidenced by a 3.17-fold increase in reported cases and a 3.02-fold escalation in incidence rate over this period. Examination of these trends revealed three distinctive developmental patterns for both males and females, with the lowest prevalence in the first trajectory and the highest in the third. The incidence was consistently higher among males than females in all trajectories. The urban and northern regions displayed equal or greater trajectory rates than their rural and southern counterparts, respectively. In terms of age groups, the lowest incidence was observed in the 0-1-year age group, while the highest was recorded in the 4-5 and 6-7-year age groups. Conclusions: Between 2010 and 2019, there was a marked increase in the incidence of scarlet fever among children in China. The disease predominantly impacts urban-dwelling children, ranging from 4 to 7 years old, in the northern regions of the country. The incidence is reported to be higher among boys compared to girls.

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