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1.
Brief Bioinform ; 2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35039845

RESUMO

Identification of adverse drug events (ADEs) is crucial to reduce human health risks and improve drug safety assessment. With an increasing number of biological and medical data, computational methods such as network-based methods were proposed for ADE prediction with high efficiency and low cost. However, previous network-based methods rely on the topological information of known drug-ADE networks, and hence cannot make predictions for novel compounds without any known ADE. In this study, we introduced chemical substructures to bridge the gap between the drug-ADE network and novel compounds, and developed a novel network-based method named ADENet, which can predict potential ADEs for not only drugs within the drug-ADE network, but also novel compounds outside the network. To show the performance of ADENet, we collected drug-ADE associations from a comprehensive database named MetaADEDB and constructed a series of network-based prediction models. These models obtained high area under the receiver operating characteristic curve values ranging from 0.871 to 0.947 in 10-fold cross-validation. The best model further showed high performance in external validation, which outperformed a previous network-based and a recent deep learning-based method. Using several approved drugs as case studies, we found that 32-54% of the predicted ADEs can be validated by the literature, indicating the practical value of ADENet. Moreover, ADENet is freely available at our web server named NetInfer (http://lmmd.ecust.edu.cn/netinfer). In summary, our method would provide a promising tool for ADE prediction and drug safety assessment in drug discovery and development.

2.
BMC Infect Dis ; 22(1): 59, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35039000

RESUMO

BACKGROUND: In March 2020, the WHO declared the novel coronavirus outbreak a global pandemic. While great success in coronavirus disease 2019 (COVID-19) control has been achieved in China, imported cases have become a major challenge. This study aimed to describe the epidemiological and clinical characteristics of imported COVID-19 cases and to assess the effectiveness of screening strategies in Beijing, China. METHODS: This retrospective study included all imported cases transferred to Beijing Ditan Hospital from 29 February to 20 March 2020 who were screened by both chest computed tomography (CT) and reverse-transcriptase-polymerase chain reaction (RT-PCR) at the initial presentation. Demographic, clinical and laboratory data, in addition to chest CT imaging, were collected and analysed. RESULTS: In total, 2545 cases were included, among which 71 (2.8%) were finally diagnosed with laboratory-confirmed COVID-19. The majority 63 (88.7%) were from Europe. The most common initial symptoms were cough and fever, which accounted for 49.3% and 42.3%, respectively. Only four cases (5.6%) had lymphocytopenia, and thirteen cases (18.3%) demonstrated elevated levels of C-reactive protein (CRP). All cases had normal serum levels of procalcitonin (PCT). At initial presentation, among the 71 confirmed cases, 59 (83.1%) had a positive RT-PCR assay, and 35 (49.3%) had a positive chest CT. Twelve (16.9%) had a negative RT-PCR assay but a positive chest CT. CONCLUSIONS: A combination of RT-PCR and chest CT is an effective strategy for the screening of imported COVID-19 cases. Our findings provide important information and clinical evidence about the infection control of imported COVID-19 cases.


Assuntos
COVID-19 , Pequim/epidemiologia , China/epidemiologia , Humanos , Pandemias , Estudos Retrospectivos , SARS-CoV-2
3.
Plant Cell Environ ; 2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35040157

RESUMO

The timely transition from vegetative to reproductive development is coordinated through the quantitative regulation of floral pathway genes in response to physiological and environmental cues. The function of ERF transcription factors in the regulation of flowering in chrysanthemum (Chrysanthemum morifolium Ramat.) is not well understood. Here, chrysanthemum overexpressing CmERF110 flowered earlier than the wild-type plants, while those in which CmERF110 was suppressed flowered later. RNA-seq results revealed that several genes involved in the circadian rhythm were transcribed differently in CmERF110 transgenic plants from that of the wild-type plants. The rhythm peak of the circadian clock genes in transgenic plants was delayed. Yeast two-hybrid screening of CmERF110 interactors identified a chrysanthemum FLK homologue CmFLK, which was further confirmed with both in vitro and in vivo assays. KEGG pathway enrichment also revealed that CmFLK is involved in the regulation of circadian rhythm-related genes. CmFLK transgenic plants showed a change in flowering time and delayed rhythm peak of the circadian rhythm genes. Taken together, the present data not only suggest that CmERF110 interacts with CmFLK to promote floral transition by tuning the circadian clock, but also provides evidence for the evolutionary conservation of the components in the autonomous pathway in chrysanthemum. This article is protected by copyright. All rights reserved.

4.
J Chem Inf Model ; 2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35041411

RESUMO

Estrogen-related receptor α (ERRα), a member of nuclear receptors (NRs), plays a role in the regulation of cellular energy metabolism and is reported to be a novel potential target for type 2 diabetes therapy. To date, only a few agonists of ERRα have been identified to improve insulin sensitivity and decrease blood glucose levels. Herein, the discovery of novel potent agonists of ERRα determined using a combined virtual screening approach is described. Molecular dynamics (MD) simulations were used to obtain structural ensembles that can consider receptor flexibility. Then, an efficient virtual screening strategy with a combination of similarity search and ensemble docking was performed against the Enamine, SPECS, and Drugbank databases to identify potent ERRα agonists. Finally, a total of 66 compounds were purchased for experimental testing. Biological investigation of promising candidates identified seven compounds that have activity against ERRα with EC50 values ranging from 1.11 to 21.70 µM, with novel scaffolds different from known ERRα agonists until now. Additionally, the molecule GX66 showed micromolar inverse activity against ERRα with an IC50 of 0.82 µM. The predicted binding modes showed that these compounds were anchored in ERRα-LBP via interactions with several residues of ERRα. Overall, this study not only identified the novel potent ERRα agonists or an inverse agonist that would be the promising starting point for further exploration but also demonstrated a successful molecular dynamics-guided approach applicable in virtual screening for ERRα agonists.

5.
Int Immunopharmacol ; 102: 108395, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34915410

RESUMO

Septic acute kidney injury (AKI) always accounts for high mortality of septic patients in ICU. Due to its not well understood mechanism for infection and immune-regulation in kidney dysfunction, there is a lack of effective therapy without side effects. Dimethyl fumarate (DMF) as an immunomodulatory molecule has been approved for treatment to multiple sclerosis. However, the therapeutic effect and immunomodulatory role underlying DMF action in septic AKI is unclear. This study aimed to elucidate the role of DMF in lipopolysaccharide (LPS)-induced septic AKI involving macrophage regulation. In current study, we administered DMF by oral gavage to mice with LPS-induced AKI, then harvested serum and kidney at three different time points. We further isolated Bone marrow-derived macrophages (BMDMs) from mice and stimulated them with LPS followed by DMF treatment. To explore immunomodulatory role of DMF in macrophages, we depleted macrophages in mice using liposomal clodronate after DMF treatment upon LPS-induced septic AKI. Then we observed that DMF attenuated renal dysfunction and murine pathological kidney injury after LPS injection. DMF could inhibit translocation of phosphorylated NF-κB p65 and suppress macrophage activation in LPS-induced AKI. DMF reduced the secretion of TNF-α and IL-6 whereas increased the secretion of IL-10 and Arg-1 in BMDMs after LPS stimulation. DMF also inhibited NF-κB p65 phosphorylation in BMDMs after LPS stimulation. Importantly, the effect of DMF against LPS-induced AKI, macrophage activation, and translocation of phosphorylated NF-κB p65 was impaired upon macrophage depletion. Thus, DMF could attenuate LPS-induced septic AKI by suppression of NF-κB p65 phosphorylation and macrophage activation. This work suggested the potential therapeutic role of DMF for patients in ICU threatened by septic AKI.

6.
Nat Commun ; 12(1): 7142, 2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34880251

RESUMO

Tumour lineage plasticity is an emerging hallmark of aggressive tumours. Tumour cells usually hijack developmental signalling pathways to gain cellular plasticity and evade therapeutic targeting. In the present study, the secreted protein growth and differentiation factor 1 (GDF1) is found to be closely associated with poor tumour differentiation. Overexpression of GDF1 suppresses cell proliferation but strongly enhances tumour dissemination and metastasis. Ectopic expression of GDF1 can induce the dedifferentiation of hepatocellular carcinoma (HCC) cells into their ancestral lineages and reactivate a broad panel of cancer testis antigens (CTAs), which further stimulate the immunogenicity of HCC cells to immune-based therapies. Mechanistic studies reveal that GDF1 functions through the Activin receptor-like kinase 7 (ALK7)-Mothers against decapentaplegic homolog 2/3 (SMAD2/3) signalling cascade and suppresses the epigenetic regulator Lysine specific demethylase 1 (LSD1) to boost CTA expression. GDF1-induced tumour lineage plasticity might be an Achilles heel for HCC immunotherapy. Inhibition of LSD1 based on GDF1 biomarker prescreening might widen the therapeutic window for immune checkpoint inhibitors in the clinic.

7.
Inorg Chem ; 2021 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-34872246

RESUMO

A novel organic-inorganic hybrid perovskite crystal, [ClC6H4(CH2)2NH3]2CuBr4 (1), having experienced an invertible high-temperature phase transition near Tc (the Curie temperature Tc = 355 K), has been successfully synthesized. The phase-transition characteristics for compound 1 are thoroughly revealed by specific heat capacity (Cp), differential thermal analysis, and differential scanning calorimetry tests, possessing 16 K broad thermal hysteresis. Multiple-temperature powder X-ray diffraction analysis further proves the phase-transition behavior of compound 1. Moreover, compound 1 exhibits a significant steplike dielectric response near Tc, revealing that it can be deemed to be a promising dielectric switching material. The variable-temperature fluorescence experiments show distinct photoluminescence (PL) changes of compound 1. Further investigation and calculation disclose that the fluorescence lifetime of compound 1 can reach as long as 55.46 µs, indicating that it can be a potential PL material. All of these researches contribute a substitutable avenue in the design and construction of neoteric phase-transition compounds combining high Curie temperature and PL properties.

8.
Nucleic Acids Res ; 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34850920

RESUMO

MicroRNAs (miRNAs) are noncoding RNAs with 18-26 nucleotides; they pair with target mRNAs to regulate gene expression and produce significant changes in various physiological and pathological processes. In recent years, the interaction between miRNAs and their target genes has become one of the mainstream directions for drug development. As a large-scale biological database that mainly provides miRNA-target interactions (MTIs) verified by biological experiments, miRTarBase has undergone five revisions and enhancements. The database has accumulated >2 200 449 verified MTIs from 13 389 manually curated articles and CLIP-seq data. An optimized scoring system is adopted to enhance this update's critical recognition of MTI-related articles and corresponding disease information. In addition, single-nucleotide polymorphisms and disease-related variants related to the binding efficiency of miRNA and target were characterized in miRNAs and gene 3' untranslated regions. miRNA expression profiles across extracellular vesicles, blood and different tissues, including exosomal miRNAs and tissue-specific miRNAs, were integrated to explore miRNA functions and biomarkers. For the user interface, we have classified attributes, including RNA expression, specific interaction, protein expression and biological function, for various validation experiments related to the role of miRNA. We also used seed sequence information to evaluate the binding sites of miRNA. In summary, these enhancements render miRTarBase as one of the most research-amicable MTI databases that contain comprehensive and experimentally verified annotations. The newly updated version of miRTarBase is now available at https://miRTarBase.cuhk.edu.cn/.

9.
Nucleic Acids Res ; 2021 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-34850139

RESUMO

Circular RNAs (circRNAs), which are single-stranded RNA molecules that have individually formed into a covalently closed continuous loop, act as sponges of microRNAs to regulate transcription and translation. CircRNAs are important molecules in the field of cancer diagnosis, as growing evidence suggests that they are closely related to pathological cancer features. Therefore, they have high potential for clinical use as novel cancer biomarkers. In this article, we present our updates to CircNet (version 2.0), into which circRNAs from circAtlas and MiOncoCirc, and novel circRNAs from The Cancer Genome Atlas database have been integrated. In total, 2732 samples from 37 types of cancers were integrated into CircNet 2.0 and analyzed using several of the most reliable circRNA detection algorithms. Furthermore, target miRNAs were predicted from the full-length circRNA sequence using three reliable tools (PITA, miRanda and TargetScan). Additionally, 384 897 experimentally verified miRNA-target interactions from miRTarBase were integrated into our database to facilitate the construction of high-quality circRNA-miRNA-gene regulatory networks. These improvements, along with the user-friendly interactive web interface for data presentation, search, and visualization, showcase the updated CircNet database as a powerful, experimentally validated resource, for providing strong data support in the biomedical fields. CircNet 2.0 is currently accessible at https://awi.cuhk.edu.cn/∼CircNet.

10.
Front Psychol ; 12: 754370, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34970190

RESUMO

Grounded in the self-determination theory and the metacognitive and affective model of self-regulated learning, this study investigated the longitudinal relationship of self-determined motivation as the antecedent and academic performance as the consequence of metacognitive knowledge (MK) in mathematics learning. Two waves of data were collected from senior high school students (N = 327) in the second semester in Grades 10 and 11. A longitudinal mediation model was analyzed using structural equation modeling. Results revealed that autonomous motivation was positively related to MK of competence-enhancing strategies and negatively related to MK of avoidance strategies. Furthermore, mathematics performance was positively predicted by MK of cognitive/metacognitive strategies and negatively predicted by MK of avoidance strategies. This study expands the understanding of MK and elaborates on the dynamics between MK, self-determined motivation, and mathematics performance. Especially, this study differentiates the MK of adaptive and maladaptive strategies and examines their motivational antecedents and academic effects. Our findings also suggest that autonomous motivation has longitudinal benefits on MK.

11.
Chem Sci ; 12(39): 13061-13067, 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34745536

RESUMO

Low-dimensional chiral organic-inorganic hybrid metal halides have attracted a lot of attention in recent years due to their unique intrinsic properties, including having potential applications in optoelectronic and spintronic devices. However, low-dimensional chiral molecular ferroelectrics are very rare. In this paper, we report a novel zero-dimensional molecular ferroelectric (C9H14N)2CdBr4 (C9H14N+ = protonated 3-phenylpropylamine), which has obvious dielectric and thermal anomalies and shows a high Curie temperature at 395 K. It crystallizes in the P21 space group at room temperature, showing a strong CD signal, large spontaneous polarization (P s = 13.5 µC cm-2), and a clear ferroelectric domain. In addition, it also exhibits a flexible SHG response. The photoluminescence spectrum shows that 1 has broadband luminescence. At the same time, compound 1 has a wide band gap, which is mainly contributed to by the inorganic CdBr4 tetrahedron. The high tunability of low-dimensional chiral molecular ferroelectrics also opens up a way to explore multifunctional chiral materials.

12.
Clin Nutr ; 40(12): 5802-5811, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34775223

RESUMO

BACKGROUND & AIMS: The strategy of increasing the postoperative enteral nutrition dose to the target goal has not yet been clarified. This study aimed to determine whether an immediate goal-dose enteral nutrition (IGEN) strategy is non-inferior to a gradual goal-dose enteral nutrition (GGEN) strategy in reducing infections in patients undergoing abdominal surgery involving the organs of the digestive system. METHODS: This randomized controlled trial enrolled postoperative patients with nutritional risk screening 2002 scores ≥3 from 11 Chinese hospitals. Energy targets were calculated as 25 kcal/kg and 30 kcal/kg of ideal body weight for women and men, respectively. Patients were randomly assigned 1:1 to IGEN or GGEN group after enteral tolerance was confirmed (30% of the target on day 2). The IGEN group immediately started receiving 100% of the caloric requirements on day 3, while the GGEN group received 40% progressing to 80% of target on day 7. The primary endpoint was the infection rate until discharge, based on the intention-to-treat population. RESULTS: A total of 411 patients were enrolled and randomized to the IGEN and GGEN groups, and five patients did not receive the allocated intervention. A total of 406 patients were included in the primary analysis, with 199 and 207 in the IGEN and GGEN groups, respectively. Infection was observed in 17/199 (8.5%) in the IGEN group and 19/207 (9.2%) in the GGEN group, respectively (difference, -0.6%; [95% confidence interval (CI), -6.2%-4.9%]; P = 0.009 for non-inferiority test). There were significantly more gastrointestinal intolerance events with IGEN than with GGEN (58/199 [29.1%] vs. 32/207 [15.5%], P < 0.001). All other secondary endpoints were non-significant. CONCLUSIONS: Among postoperative patients at nutritional risk, IGEN was non-inferior to GGEN in regards to infectious complications. IGEN was associated with more gastrointestinal intolerance events. It showed that IGEN cannot be considered to be clinically directive. ClinicalTrials.gov (#NCT03117348).

13.
Support Care Cancer ; 2021 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-34775535

RESUMO

PURPOSE: As an antipsychotic agent that targets multiple neurotransmitter receptors, olanzapine has been added to antiemetic therapies. For better understanding the application of olanzapine in antiemetic strategies for breast cancer patients who suffered anthracycline plus cyclophosphamide-induced nausea and vomiting, we comprehensively reviewed the antiemetic researches related to olanzapine and pooled-analyzed the results to confirm the efficacy and safety of olanzapine in breast cancer. METHODS: PubMed, Web of Science, EMBASE, and Cochrane CENTRAL databases were searched from inception through Sep 15, 2021. Both prospective and retrospective studies were eligible. The primary outcomes were complete response (defined as no vomiting and no use of rescue medications) and no nausea rate, and the secondary outcome was treatment-related adverse events. RESULTS: Four studies with 466 breast cancer patients were identified in the pooled analysis. In the acute period (0-24 h), the olanzapine group had significantly higher rates of complete response (71.3% vs 48.1%, odds ratio [OR]: 2.66, 95% confidence interval [CI] 1.39-5.11, p = 0.003) and no nausea (70.0% vs 43.0%, OR: 3.55, 95% CI 1.76-7.18, p = 0.04) than the placebo group, while in the delayed period, the olanzapine group was also superior to the placebo group in terms of the complete response (82.5% vs 63.3%, OR: 3.81, 95% CI 1.58-9.15, p = 0.003) and no nausea (66.3% vs 51.9%, OR: 2.08, 95% CI 1.03-4.21, p = 0.04) rates. During the overall period in prospective studies, the proportions of complete response (50.0% vs 34.2%, OR: 1.93, p = 0.04) and no nausea (51.3% vs 25.3%, OR: 3.40, p = 0.0006) in the olanzapine group were higher than those in the placebo group. CONCLUSION: Highly emetogenic chemotherapy breast patients could benefit from olanzapine-contained antiemetic therapy. Furthermore, since the cost is low, olanzapine is worth further clinical application and promotion.

14.
ChemMedChem ; 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34755485

RESUMO

Type 2 diabetes mellitus (T2DM) is a heterogeneous disorder, so achieving the desired therapeutic efficacy through monotherapy is tricky. Drug combinations play a vital role in treating multiple complex diseases by providing increased efficacy and reduced toxicity. Here, we adopted a computational framework to discover potential drugs and drug pairs for T2DM. Firstly, we collected T2DM-associated genes and constructed the disease module for T2DM. Then, by quantifying the proximity between drugs and the disease module, we found out potential drugs. Based on the drug-induced gene expression profiles, we further performed Gene Set Enrichment Analysis (GSEA) on these drugs and identified several potential candidates. In addition, through network-based separation, potential drug combinations for T2DM were predicted. Results from this study could provide insights for anti-T2DM drug discovery and rational drug use of existing agents. As a useful computational framework, our approach could also be applied in drug research for other complex diseases.

15.
Chem Asian J ; 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34755488

RESUMO

Cyclic organic amines are emerging as excellent building blocks to assemble organic-inorganic hybrid phase transition materials due to their flexible cyclic structure. Here, we have assembled a 1D organic-inorganic hybrid dielectric material C5 H6 NOPbBr3 (1) by alloying the cyclic organic amine 3-hydroxypyridine. 1 displays a remarkable switchable dielectric response induced by an order-disorder transformation of the organic moiety, this transformation behaviour is confirmed by DSC and Hirshfeld surface measurements. More interestingly, 1 has a narrowband emission (FWHM=4.64 nm) at 590 nm; FWHM is a major quality figure for narrowband photodetectors. In addition, 1 exhibits semiconducting properties with an indirect bandgap of 2.78 eV by the analysis of the UV-Vis absorption results.

16.
Ann Palliat Med ; 10(10): 10712-10719, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34763432

RESUMO

BACKGROUND: Secondary hyperparathyroidism (SHPT) is common in dialysis patients with end-stage renal disease (ESRD). Parathyroidectomy (PTX) is an effective treatment for SHPT. Postoperative severe hypocalcemia (SH) is a common and severe complication after PTX. This study aimed to investigate the potential predictive markers of SH in dialysis ESRD patients with SHPT after near-total PTX (near-tPTX) without autotransplantation (AT). METHODS: A retrospective analysis involving 131 dialysis patients with SHPT who were treated with near-tPTX without AT between January and August 2018 was performed. Demographic characteristics (age, gender, type of dialysis modality, etc.) and perioperative laboratory parameters [serum calcium, phosphorus, alkaline phosphatase (ALP), intact parathyroid hormone (iPTH), and bone metabolism markers] were collected and analyzed. Postoperative serum calcium level <1.875 mmol/L (7.5 mg/dL) was defined as postoperative SH. RESULTS: Among the 131 patients, 73 (55.7%) had postoperative hypocalcemia and 43 (32.8%) had postoperative SH. Univariate analysis showed that values of preoperative serum iPTH, calcium, ALP, bone-specific alkaline phosphatase (BAP), and osteocalcin (OC) were significantly different between the SH and non-SH groups. In the multivariate logistic regression model, preoperative serum ALP was an independent risk predictor of postoperative SH. The receiver operating characteristic (ROC) curve for preoperative serum ALP was 277 U/L. The sensitivity of preoperative serum ALP was 73.8% and the specificity was 63.2%. CONCLUSIONS: The incidence rates of postoperative hypocalcemia and SH in dialysis patients with SHPT after near-tPTX without AT were 55.7% and 32.8%, respectively. Preoperative serum ALP was an independent predictor for the occurrence of postoperative SH, and dialysis patients with SHPT were susceptible to postoperative SH when preoperative serum ALP level was >277 U/L. Hence, we recommend that preoperative serum ALP be utilized to complement clinical protocols for postoperative SH management of dialysis ESRD patients with SHPT after near-tPTX without AT.


Assuntos
Hiperparatireoidismo Secundário , Hipocalcemia , Humanos , Hiperparatireoidismo Secundário/cirurgia , Hipocalcemia/etiologia , Paratireoidectomia , Diálise Renal/efeitos adversos , Estudos Retrospectivos
17.
Front Med (Lausanne) ; 8: 744839, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34765619

RESUMO

Gastric cancer is one of the most common cause of cancer related deaths worldwide which results in malignant tumors in the digestive tract. The only radical treatment option available is surgical resection. Recently, the implementation of neoadjuvant chemotherapy resulted in 5-year survival rates of 95% for early gastric cancer. The main reason of treatment failure is that early diagnosis is minimal, with many patients presenting advanced stages. Hence, the greatest benefit of radical resection is missed. Consequently, the main therapeutic approach for advanced gastric cancer is combined surgery with neoadjuvant chemotherapy, targeted therapy, or immunotherapy. In this review, we will discuss the various treatment options for advanced gastric cancer. Clinical practice and clinical research is the most practical way of reaching new advents in terms of patients' characteristics, optimum drug choice, and better prognosis. With the recent advances in gastric cancer diagnosis, staging, treatment, and prognosis, we are evident that the improvement of survival in this patient population is just a matter of time.

18.
Int J Mol Sci ; 22(21)2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34769028

RESUMO

Ribosome-inactivating proteins (RIPs) hydrolyze the N-glycosidic bond and depurinate a specific adenine residue (A-4324 in rat 28S ribosomal RNA, rRNA) in the conserved α-sarcin/ricin loop (α-SRL) of rRNA. In this study, we have purified and characterized lyophyllin, an unconventional RIP from Lyophyllum shimeji, an edible mushroom. The protein resembles peptidase M35 domain of peptidyl-Lys metalloendopeptidases. Nevertheless, protein either from the mushroom or in recombinant form possessed N-glycosidase and protein synthesis inhibitory activities. A homology model of lyophyllin was constructed. It was found that the zinc binding pocket of this protein resembles the catalytic cleft of a classical RIP, with key amino acids that interact with the adenine substrate in the appropriate positions. Mutational studies showed that E122 may play a role in stabilizing the positively charged oxocarbenium ion and H121 for protonating N-3 of adenine. The tyrosine residues Y137 and Y104 may be used for stacking the target adenine ring. This work first shows a protein in the peptidase M35 superfamily based on conserved domain search possessing N-glycosidase activity.

19.
Ren Fail ; 43(1): 1551-1560, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34791966

RESUMO

Defined differently from apoptosis, necrosis, and autophagy, ferroptosis has been implicated in acute kidney injury (AKI) such as ischemia-reperfusion injury induced AKI, folic acid caused AKI and cisplatin induced AKI. However, whether ferroptosis is involved in LPS induced AKI could be remaining unclear and there is still a lack of therapies associated with ferroptosis in LPS induced AKI without side effects. This study aimed to elucidate the role of isoliquiritigenin (ISL) in ferroptosis of LPS-induced AKI. We used LPS to induce renal tubular injury, followed by treatment with ISL both in vitro and in vivo. Human renal tubular HK2 cells were pretreated with 50 µM or 100 µM ISL for 5 h before stimulation with 2 µg/mL LPS. Mice were administered a single dose of either 50 mg/kg ISL orally or 5 mg/kg ferroptosis inhibitor ferrostatin-1 intraperitoneally before 10 mg/kg LPS injection. We found that LPS could induce mitochondria injury of renal tubular presented as the shape of mitochondria appeared smaller than normal with increased membrane density and are faction or destruction of mitochondrial crista through scanning electron microscope. Ferrostatin-1 significantly protected mice against renal dysfunction and renal tubular damage in LPS-induced AKI. ISL inhibited Fe2+ and lipid peroxidation accumulation in LPS-stimulated HK2 cells. It also increased the expression of GPX4 and xCT, reduced the expression of HMGB1 and NCOA4 then attenuated mitochondria injury in renal tubular following LPS stimulation. These results indicated the potential role of ISL against ferritinophagy-mediated ferroptosis in renal tubular following LPS stimulation.

20.
World J Pediatr ; 17(6): 659-668, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34792780

RESUMO

BACKGROUND: The aim of this study was to explore the associations between the aspartate aminotransferase-to-alanine aminotransferase ratio (AST/ALT) and coronary artery lesions (CALs) among patients with Kawasaki disease (KD). METHODS: Medical records of KD patients presenting to a single center between January 2019 and December 2020 were retrospectively collected and analyzed. Univariate, multivariable-adjusted analyses, subgroup analyses, restricted cubic spline test, and fitted curves were used to evaluate the associations between AST/ALT and CALs. RESULTS: A total of 831 patients were enrolled, of which 201 (24.2%) had CALs on admission and 21 (2.5%) developed CALs de novo after intravenous immunoglobulin (IVIG). Multivariable-adjusted analyses models revealed that a lower AST/ALT was associated with an increased risk of CALs on admission when AST/ALT was a continuous variable (P = 0.007) and when it was a categorical variable (P for trend = 0.004). Each unit increase in AST/ALT was associated with a 22% lower risk of CALs on admission (odds ratio = 0.78, 95% confidence interval 0.65-0.94). A negative linear relationship was noted between AST/ALT and the risk of CALs on admission in both observed and fitted models. However, such associations were not observed in AST/ALT and CALs de novo after IVIG. None of the variables significantly modified the association between AST/ALT and CALs on admission and CALs de novo after IVIG (P > 0.05). CONCLUSION: Our findings suggested that AST/ALT was a risk factor of CALs, but was not associated with progressive CALs.

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