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1.
ACS Omega ; 9(26): 28485-28493, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38973881

RESUMO

Predicting the drug-target binding affinity (DTA) is crucial in drug discovery, and an increasing number of researchers are using artificial intelligence techniques to make such predictions. Many effective deep neural network prediction models have been proposed. However, current methods need improvement in accuracy, complexity, and efficiency. In this study, we propose a method based on a multiscale 2-dimensional convolutional neural network (CNN), namely ImageDTA. Many studies have shown that CNN achieves good learning effects with limited data. Therefore, we take a unique perspective by treating the word vector encoded with a simplified molecular input line entry system (SMILES) string as an "image" and processing it like handling images, fully leveraging the efficient processing capabilities of CNN for image data. Furthermore, we show that ImageDTA has higher training and inference efficiency than pretrained large models and outperforms attention-based graph neural network models in accuracy and interpretability. We also use visualization techniques to select appropriate convolutional kernel sizes, thereby increasing the network's interpretability.

2.
Appl Opt ; 63(13): 3576-3584, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38856543

RESUMO

Spectral imaging technology based on on-chip spectroscopy can find applications in areas including aerospace, industrial and consumer electronics, and so on. Since each application normally requires a different set and number of spectral bands, the development of customized spectroscopy solutions with more compact size and lower cost becomes quite important. In this paper, we demonstrate a compact, highly customizable imaging spectrometer scheme based on custom-made multi-strip filter arrays, which maintains an average high transmission of ∼85%, narrow bandwidth of ∼30n m, and high optical density of ∼O D2 in the blocking regions across the visible to near-infrared waveband. Spectral imaging experiments are conducted, and the accurate reconstruction of sparse spectral image data is demonstrated as well to prove the validity of the proposed scheme. As a result, the work reported in this paper allows researchers to develop customized spectral imaging equipment in a relatively easy way and also has a great potential to be engineered further for scalable production with a quite low cost.

3.
J Food Sci ; 89(7): 4192-4204, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38829742

RESUMO

Opuntia ficus-indica fruit (OFI) is rich in bioactive compounds, which can promote human health. In this work, the purified OFI extract was prepared from OFI and its bioactivities were investigated. Xanthine oxidase (XOD) and α-glucosidase (α-Glu) inhibitors of the purified OFI extract were screened and identified by bio-affinity ultrafiltration combined with UPLC-QTRAP-MS/MS technology. The inhibitory effect of these inhibitors on enzymes were verified, and the potential mechanism of action and binding sites of inhibitors with enzymes were revealed based on molecular docking. The results showed that the total phenolic content of the purified OFI extract was 355.03 mg GAE/g DW, which had excellent antioxidant activity. Additionally, the extract had a certain inhibitory effect on XOD (IC50 = 199.00 ± 0.14 µg/mL) and α-Glu (IC50 = 159.67 ± 0.01 µg/mL). Seven XOD inhibitors and eight α-Glu inhibitors were identified. Furthermore, XOD and α-Glu inhibition experiments in vitro confirmed that inhibitors such as chlorogenic acid, taxifolin, and naringenin had significant inhibitory effects on XOD and α-Glu. The molecular docking results indicated that inhibitors could bind to the corresponding enzymes and had strong binding force. These findings demonstrate that OFI contains potential substances for the treatment of hyperuricemia and hyperglycemia.


Assuntos
Frutas , Inibidores de Glicosídeo Hidrolases , Simulação de Acoplamento Molecular , Opuntia , Extratos Vegetais , Xantina Oxidase , alfa-Glucosidases , Xantina Oxidase/antagonistas & inibidores , Inibidores de Glicosídeo Hidrolases/farmacologia , Frutas/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , alfa-Glucosidases/metabolismo , alfa-Glucosidases/química , Opuntia/química , Antioxidantes/farmacologia , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Espectrometria de Massas em Tandem/métodos , Fenóis/farmacologia , Fenóis/química , Flavanonas/farmacologia
4.
Nature ; 631(8020): 319-327, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38898275

RESUMO

Naturally occurring (native) sugars and carbohydrates contain numerous hydroxyl groups of similar reactivity1,2. Chemists, therefore, rely typically on laborious, multi-step protecting-group strategies3 to convert these renewable feedstocks into reagents (glycosyl donors) to make glycans. The direct transformation of native sugars to complex saccharides remains a notable challenge. Here we describe a photoinduced approach to achieve site- and stereoselective chemical glycosylation from widely available native sugar building blocks, which through homolytic (one-electron) chemistry bypasses unnecessary hydroxyl group masking and manipulation. This process is reminiscent of nature in its regiocontrolled generation of a transient glycosyl donor, followed by radical-based cross-coupling with electrophiles on activation with light. Through selective anomeric functionalization of mono- and oligosaccharides, this protecting-group-free 'cap and glycosylate' approach offers straightforward access to a wide array of metabolically robust glycosyl compounds. Owing to its biocompatibility, the method was extended to the direct post-translational glycosylation of proteins.


Assuntos
Técnicas de Química Sintética , Oligossacarídeos , Açúcares , Radicais Livres/química , Radicais Livres/metabolismo , Glicosilação/efeitos da radiação , Indicadores e Reagentes/química , Luz , Oligossacarídeos/síntese química , Oligossacarídeos/química , Oligossacarídeos/metabolismo , Oligossacarídeos/efeitos da radiação , Estereoisomerismo , Açúcares/síntese química , Açúcares/química , Açúcares/metabolismo , Açúcares/efeitos da radiação
5.
Neurochem Int ; 177: 105764, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38729355

RESUMO

Increasing evidence supported that oxidative stress induced by herniated lumbar disc played important role in the formation of lumbar disc herniation sciatica (LDHS), however, the neural mechanisms underlying LDHS need further clarification. Endomorphin-2 (EM2) is the endogenous ligand for mu-opioid receptor (MOR), and there is increasing evidence implicating the involvement of spinal EM2 in neuropathic pain. In this study, using an nucleus pulposus implantation induced LDHS rat model that displayed obvious mechanical allodynia, it was found that the expression of EM2 in dorsal root ganglion (DRG) and spinal cord was significantly decreased. It was further found that oxidative stress in DRG and spinal cord was significantly increased in LDHS rats, and the reduction of EM2 in DRG and spinal cord was determined by oxidative stress dominated increment of dipeptidylpeptidase IV activity. A systemic treatment with antioxidant could prevent the forming of mechanical allodynia in LDHS rats. In addition, MOR expression in DRG and spinal cord remained unchanged in LDHS rats. Intrathecal injection of MOR antagonist promoted pain behavior in LDHS rats, and the analgesic effect of intrathecal injection of EM2 was stronger than that of endomorphin-1 and morphine. Taken together, our findings suggest that oxidative stress mediated decrement of EM2 in DRG and spinal cord causes the loss of endogenous analgesic effects and enhances the pain sensation of LDHS.


Assuntos
Deslocamento do Disco Intervertebral , Oligopeptídeos , Estresse Oxidativo , Ratos Sprague-Dawley , Ciática , Animais , Estresse Oxidativo/fisiologia , Estresse Oxidativo/efeitos dos fármacos , Deslocamento do Disco Intervertebral/metabolismo , Ratos , Oligopeptídeos/farmacologia , Ciática/metabolismo , Ciática/tratamento farmacológico , Masculino , Medula Espinal/metabolismo , Medula Espinal/efeitos dos fármacos , Vértebras Lombares , Gânglios Espinais/metabolismo , Gânglios Espinais/efeitos dos fármacos , Receptores Opioides mu/metabolismo
6.
J Am Chem Soc ; 146(15): 10274-10280, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38568080

RESUMO

The construction of C(sp3)-C(sp3) bonds remains one of the most difficult challenges in cross-coupling chemistry. Here, we report a photoredox/nickel dual catalytic approach that enables the simultaneous formation of two C(sp3)-C(sp3) linkages via trimolecular cross-coupling of alkenes with alkyl halides and hypervalent iodine-based reagents. The reaction harnesses a bimolecular homolytic substitution (SH2) mechanism and chemoselective halogen-atom transfer (XAT) to orchestrate the regioselective addition of electrophilic and nucleophilic alkyl radicals across unactivated alkenes without the need for a directing auxiliary. Utility is highlighted through late-stage (fluoro)alkylation and (trideutero)methylation of C═C bonds bearing different substitution patterns, offering straightforward access to drug-like molecules comprising sp3-hybridized carbon scaffolds.

7.
Appl Opt ; 63(8): 1929-1933, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38568630

RESUMO

Nanocomposite scintillators are expected to combine the advantages of inorganic and plastic scintillators, such as high detection efficiency, high light yield, fast decay time, low cost, and ease of processing. They are currently the forefront and hot field of scintillator research. In this study, a non-destructive method was developed for measuring the content of inorganic components in nanocomposite scintillators by terahertz time-domain spectroscopy. The complex refractive index of B a F 2 nanocomposite scintillators with different mass contents was measured in the terahertz band. As the mass content of B a F 2 nanoparticles increases, the refractive index and extinction coefficient of B a F 2 nanocomposite scintillators also gradually increase in the terahertz band. By combining the effective medium theory, the expected mass content was obtained, proving the feasibility of this measuring method.

8.
Se Pu ; 42(3): 291-295, 2024 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-38503706

RESUMO

A method was developed for the determination of trace anions in battery-grade lithium carbonate. In this method, lithium carbonate was dissolved in ultrapure water with ultrasound assistance, and its matrix was removed using an on-line matrix-removal method. In the matrix-removal process, the sample was first passed through an ADRS600(4 mm) suppressor (suppressor current, 150 mA; external water flow rate, 2 mL/min). Hydrogen and lithium ions were then completely exchanged via the ion-exchange membrane in the suppressor, converting the lithium carbonate into carbonic acid. The carbonic acid entered the waste-liquid channel in the form of carbon dioxide through a CRD 200(4 mm) carbonate removal device to remove the lithium carbonate matrix. Finally, the target anions were automatically enriched on an IonPac UTAC-LP2 concentration column (35 mm×3 mm) and automatically transferred to a chromatographic system using valve-switching technology. The chromatographic system featured an IonPac AG18 column (50 mm×2 mm) as the protection column and an IonPac AS18 column (250 mm×2 mm) as the analytical column. The column temperature was 30 ℃, gradient elution was performed using KOH solution as the eluent, and the pump flow rate was 0.30 mL/min. An ADRS600(2 mm) suppressor, suppressor current of 25 mA, injection volume of 250 µL, and conductance detector were also used. The results showed good linear relationships (r≥ 0.999) for F-, Cl-, [Formula: see text] in their respective concentration ranges. The limits of detection (LODs) and quantification (LOQs) were 0.05-0.88 and 0.15-2.92 µg/L, respectively. Lithium carbonate samples were tested six consecutive times, and the relative standard deviations (RSDs) of the peak areas of each ion were less than 0.73%. The same lithium carbonate samples were injected after 0, 2, 4, 8, 12, 18, and 24 h, and the RSD of the peak areas of each ion was less than 0.96%. The average recoveries ranged from 93.3% to 99.3%, and the RSDs (n=6) of samples spiked at three levels were in the range of 0.97%-3.45%. The proposed method has a low method limit of quantification of only 0.5 mg/kg for each ion analyzed and is capable of the simultaneous analysis of multiple ions. Thus, it is suitable for the detection of trace anions in battery-grade lithium carbonate.

9.
Orthop Surg ; 16(4): 851-863, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38384172

RESUMO

OBJECTIVE: The connection between alterations in the disc structure following percutaneous endoscopic lumbar discectomy (PELD) and symptoms in patients postsurgery has not been reported yet. The purpose of the present study was to discuss the potential correlation between the changes in the morphological characteristics of various reference surfaces of the intervertebral disc after percutaneous endoscopic lumbar discectomy (PELD) and clinical outcomes, to identify the morphological parameters that affect efficacy and provide an evidence-based foundation for assessing postoperative efficacy. METHODS: From October 2019 to October 2021, after percutaneous endoscopic lumbar discectomy (PELD), 98 individuals were enrolled. MRI DICOM data of the lumbar spine were obtained before and after surgery, specifically around 3 months. The morphological parameters of the operated and adjacent segments of the discs were measured using T2-weighted images from three reference planes. Outcomes were assessed using the Oswestry disability index (ODI), visual analogue pain scores for the back and leg (VAS-back/VAS-leg), Japanese Orthopaedic Association (JOA) scores, and recovery rates. Postoperative changes in disc parameters and outcomes were compared between patients with different severity and types of LDH based on the MSU staging. Patients completed the questionnaire during outpatient follow-up appointments 3, 6, and 12 months after the surgery. The follow-up period was 14.69 ± 4.21 months, ranging from 12 to 24 months. RESULTS: Parameters such as area and circumference of intervertebral discs in the cross-section were not associated with the change in the efficacy index. Postoperatively, a negative correlation between the variation of the disc height, disc height index, and protrusion distance and the difference in VAS scores for low back pain at 3 and 6 months was observed among the two sagittal change parameters. Differences between changes in disc imaging parameters and postoperative efficacy were not statistically significant between various types of lumbar disc herniation. CONCLUSION: For the patients after percutaneous endoscopic lumbar discectomy, the changes in parameters such as disc area and circumference in the cross-sectional plane are not associated with efficacy, and the changes in disc height and herniation distance in the sagittal plane provide a morphologic basis for the assessment of short-term postoperative efficacy. In addition, the changes in disc morphologic parameters and postoperative efficacy do not differ between various types of lumbar disc herniation.


Assuntos
Discotomia Percutânea , Deslocamento do Disco Intervertebral , Humanos , Seguimentos , Deslocamento do Disco Intervertebral/diagnóstico por imagem , Deslocamento do Disco Intervertebral/cirurgia , Deslocamento do Disco Intervertebral/etiologia , Discotomia Percutânea/métodos , Estudos Transversais , Endoscopia/métodos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Resultado do Tratamento , Estudos Retrospectivos , Discotomia/métodos
10.
Sci Rep ; 14(1): 4318, 2024 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-38383657

RESUMO

The principal aim of this investigation is to identify pivotal biomarkers linked to the prognosis of osteosarcoma (OS) through the application of artificial intelligence (AI), with an ultimate goal to enhance prognostic prediction. Expression profiles from 88 OS cases and 396 normal samples were procured from accessible public databases. Prognostic models were established using univariate COX regression analysis and an array of AI methodologies including the XGB method, RF method, GLM method, SVM method, and LASSO regression analysis. Multivariate COX regression analysis was also employed. Immune cell variations in OS were examined using the CIBERSORT software, and a differential analysis was conducted. Routine blood data from 20,679 normal samples and 437 OS cases were analyzed to validate lymphocyte disparity. Histological assessments of the study's postulates were performed through immunohistochemistry and hematoxylin and eosin (HE) staining. AI facilitated the identification of differentially expressed genes, which were utilized to construct a prognostic model. This model discerned that the survival rate in the high-risk category was significantly inferior compared to the low-risk cohort (p < 0.05). SERPINE2 was found to be positively associated with memory B cells, while CPT1B correlated positively with CD8 T cells. Immunohistochemical assessments indicated that SERPINE2 was more prominently expressed in OS tissues relative to adjacent non-tumorous tissues. Conversely, CPT1B expression was elevated in the adjacent non-tumorous tissues compared to OS tissues. Lymphocyte counts from routine blood evaluations exhibited marked differences between normal and OS groups (p < 0.001). The study highlights SERPINE2 and CPT1B as crucial biomarkers for OS prognosis and suggests that dysregulation of lymphocytes plays a significant role in OS pathogenesis. Both SERPINE2 and CPT1B have potential utility as prognostic biomarkers for OS.


Assuntos
Neoplasias Ósseas , Osteossarcoma , Humanos , Prognóstico , Serpina E2 , Inteligência Artificial , Biomarcadores , Osteossarcoma/diagnóstico , Carnitina O-Palmitoiltransferase
11.
Sci Rep ; 14(1): 4352, 2024 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-38388661

RESUMO

Gastric cancer (GC), known for its high incidence and poor prognosis, urgently necessitates the identification of reliable prognostic biomarkers to enhance patient outcomes. We scrutinized data from 375 GC patients alongside 32 non-cancer controls, sourced from the TCGA database. A univariate Cox Proportional Hazards Model (COX) regression was employed to evaluate expressions of ferroptosis-related genes. This was followed by the application of Least Absolute Shrinkage and Selection Operator (LASSO) and multivariate COX regression for the development of prognostic models. The composition of immune cell subtypes was quantified utilizing CIBERSORT, with their distribution in GC versus control samples being comparatively analyzed. Furthermore, the correlation between the expressions of Cystathionine Gamma-Lyase (CTH) and Microtubule Associated Protein 1 Light Chain 3 Beta (MAP1LC3B) and the abundance of immune cell subtypes was explored. Our bioinformatics findings underwent validation through immunohistochemical analysis. Our prognostic models integrated CTH and MAP1LC3B. Survival analysis indicated that patients categorized as high-risk, as defined by the model, exhibited significantly lower survival rates compared to their low-risk counterparts. Notably, CTH expression inversely correlated with monocyte levels, while MAP1LC3B expression showed an inverse relationship with the abundance of M2 macrophages. Immunohistochemical validation corroborated lower expressions of CTH and MAP1LC3B in GC tissues relative to control samples, in concordance with our bioinformatics predictions. Our study suggests that the dysregulation of CTH, MAP1LC3B, and the accompanying monocyte-macrophage dynamics could be pivotal in the prognosis of GC. These elements present potential targets for prognostic assessment and therapeutic intervention.


Assuntos
Ferroptose , Neoplasias Gástricas , Humanos , Biomarcadores , Cistationina gama-Liase/metabolismo , Proteínas Associadas aos Microtúbulos , Prognóstico , Neoplasias Gástricas/genética
12.
Mol Med ; 30(1): 32, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38424494

RESUMO

BACKGROUND: Endothelial-to-Mesenchymal Transformation (EndMT) plays key roles in endothelial dysfunction during the pathological progression of atherosclerosis; however, its detailed mechanism remains unclear. Herein, we explored the biological function and mechanisms of upstream stimulating factor 1 (USF1) in EndMT during atherosclerosis. METHODS: The in vivo and in vitro atherosclerotic models were established in high fat diet-fed ApoE-/- mice and ox-LDL-exposed human umbilical vein endothelial cells (HUVECs). The plaque formation, collagen and lipid deposition, and morphological changes in the aortic tissues were evaluated by hematoxylin and eosin (HE), Masson, Oil red O and Verhoeff-Van Gieson (EVG) staining, respectively. EndMT was determined by expression levels of EndMT-related proteins. Target molecule expression was detected by RT-qPCR and Western blotting. The release of pro-inflammatory cytokines was measured by ELISA. Migration of HUVECs was detected by transwell and scratch assays. Molecular mechanism was investigated by dual-luciferase reporter assay, ChIP, and Co-IP assays. RESULTS: USF1 was up-regulated in atherosclerosis patients. USF1 knockdown inhibited EndMT by up-regulating CD31 and VE-Cadherin, while down-regulating α-SMA and vimentin, thereby repressing inflammation, and migration in ox-LDL-exposed HUVECs. In addition, USF1 transcriptionally activated ubiquitin-specific protease 14 (USP14), which promoted de-ubiquitination and up-regulation of NLR Family CARD Domain Containing 5 (NLRC5) and subsequent Smad2/3 pathway activation. The inhibitory effect of sh-USF1 or sh-USP14 on EndMT was partly reversed by USP14 or NLRC5 overexpression. Finally, USF1 knockdown delayed atherosclerosis progression via inhibiting EndMT in mice. CONCLUSION: Our findings indicate the contribution of the USF1/USP14/NLRC5 axis to atherosclerosis development via promoting EndMT, which provide effective therapeutic targets.


Assuntos
Aterosclerose , Transição Endotélio-Mesênquima , Humanos , Camundongos , Animais , Transdução de Sinais , Aterosclerose/metabolismo , Células Endoteliais da Veia Umbilical Humana , Regulação para Cima , Fatores Estimuladores Upstream/metabolismo , Fatores Estimuladores Upstream/farmacologia , Ubiquitina Tiolesterase/metabolismo , Ubiquitina Tiolesterase/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo
13.
Inorg Chem ; 63(6): 3075-3082, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38295520

RESUMO

Herein, an unprecedented cadmium-based metal-organic framework (JNU-106) fabricated by utilizing pyrazole-functionalized tetraphenylethylene ligands (Py-TPE) and rod-shaped secondary building units is reported, possessing a new (3,3,3,6,6,8)-connected topological network. Thanks to the ingeniously designed intramolecular charge transfer behavior, which originates from the congruent coplanarity between Py and TPE, JNU-106 exhibits intense green luminescence with a quantum yield increased by 1.5 times. The phenomenon of remarkable fluorescence quenching of JNU-106 reveals that it possesses extremely high anti-interference performance, superior sensitivity, and dedicated selectivity toward tetracycline antibiotics (TCAs) in aqueous solutions, which are comparable to those of the state-of-the-art porous sensing compounds. Taking the theoretical calculations and experimental results into account, the luminescence quenching is mainly attributed to the internal filtration effect and the static quenching effect. Considering the portable and rapid performance of JNU-106-based testing strips for sensing TCAs, the fabricated JNU-106 provides an alternative for ecological monitoring and environmental governance.

14.
World J Oncol ; 15(1): 28-37, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38274726

RESUMO

The dynamic changes between glycolysis and oxidative phosphorylation (OXPHOS) for adenosine triphosphate (ATP) output, along with glucose, glutamine, and fatty acid utilization, etc., lead to the maintenance and selection of growth advantageous to tumor cell subgroups in an environment of iron starvation and hypoxia. Iron plays an important role in the three major biochemical reactions in nature: photosynthesis, nitrogen fixation, and oxidative respiration, which all require the participation of iron-sulfur proteins, such as ferredoxin, cytochrome b, and the complex I, II, III in the electron transport chain, respectively. Abnormal iron-sulfur cluster synthesis process or hypoxia will directly affect the function of mitochondrial electron transfer and mitochondrial OXPHOS. More research results have indicated that iron metabolism, oxygen availability and hypoxia-inducible factor mutually regulate the shift between glycolysis and OXPHOS. In this article, we make a perspective review to provide novel opinions of the regulation of glycolysis and OXPHOS in tumor cells.

15.
Heliyon ; 10(1): e23256, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38192786

RESUMO

Importance: The global COVID-19 pandemic does not appear to end in the near future. Currently, limited data are available on the risk factors for delayed viral clearance in patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant infection. Objective: This study aimed to investigate the association of clinical characteristics and vaccination with prolonged viral clearance. Methods: This retrospective cohort included 16,985 patients who had contracted the SARS-CoV-2 Omicron variant between April 5 and May 30, 2022, in Shanghai, China, and had mild or no symptoms. The patients were admitted to the quarantine venue at the Shanghai New International Expo Center. Results: Of the 16,985 participants, the occurrence of viral clearance was ≤8 and > 8 days in 11,009 (64.8 %) and 5976 (35.2 %) participants, respectively. Risk factors related to patients who remained persistently polymerase chain reaction (PCR)-positive were sex (Male, odds ratio [OR] 1.221, p < 0.001), older age (35-49, OR 1.389, p < 0.001; 50-64, OR 1.659, p < 0.001; ≥65, OR 2.139, p < 0.001), presence of symptoms (OR 1.093, p = 0.030), number of vaccinations (two doses, OR 0.753, p < 0.001; three doses, OR 0.797, p < 0.001; four doses, OR 0.543, p < 0.001), and cycle threshold (Ct) value for ORF1ab gene at diagnosis (25-35, OR 0.235, p < 0.001; >35, OR 0.079, p < 0.001). The lower rates of increase in Ct values were observed in the later viral shedding group than in the early viral shedding group for ORF1ab (ß = -0.791, p < 0.001) and N genes (ß = -0.825, p < 0.001). Conclusion: Prolonged SARS-CoV-2 RNA detection and higher viral concentrations were associated with factors such as male sex, older age, symptomatic status, and fewer doses of vaccination in patients admitted to Shanghai Makeshift Hospital between April 5 and May 30, 2022.

16.
Nat Commun ; 14(1): 7654, 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-37996405

RESUMO

Previous studies have demonstrated that bis-(3',5')-cyclic diguanosine monophosphate (bis-3',5'-c-di-GMP) is a ubiquitous second messenger employed by bacteria. Here, we report that 2',3'-cyclic guanosine monophosphate (2',3'-cGMP) controls the important biological functions, quorum sensing (QS) signaling systems and virulence in Ralstonia solanacearum through the transcriptional regulator RSp0980. This signal specifically binds to RSp0980 with high affinity and thus abolishes the interaction between RSp0980 and the promoters of target genes. In-frame deletion of RSp0334, which contains an evolved GGDEF domain with a LLARLGGDQF motif required to catalyze 2',3'-cGMP to (2',5')(3',5')-cyclic diguanosine monophosphate (2',3'-c-di-GMP), altered the abovementioned important phenotypes through increasing the intracellular 2',3'-cGMP levels. Furthermore, we found that 2',3'-cGMP, its receptor and the evolved GGDEF domain with a LLARLGGDEF motif also exist in the human pathogen Salmonella typhimurium. Together, our work provides insights into the unusual function of the GGDEF domain of RSp0334 and the special regulatory mechanism of 2',3'-cGMP signal in bacteria.


Assuntos
Guanosina Monofosfato , Ralstonia solanacearum , Humanos , Virulência , Ralstonia solanacearum/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , GMP Cíclico/metabolismo , Sistemas do Segundo Mensageiro , Regulação Bacteriana da Expressão Gênica , Biofilmes
17.
Appl Environ Microbiol ; 89(12): e0107423, 2023 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-38032177

RESUMO

IMPORTANCE: Shigella sonnei is a major human enteric pathogen that causes bacillary dysentery. The increasing spread of drug-resistant S. sonnei strains has caused an emergent need for the development of new antimicrobial agents against this pathogenic bacterium. In this study, we demonstrate that Stattic employs two antibacterial mechanisms against S. sonnei. It exerted both anti-virulence activity and bactericidal activity against S. sonnei, suggesting that it shows advantages over traditional antibiotics. Moreover, Stattic showed excellent synergistic effects with kanamycin, ampicillin, chloramphenicol, and gentamicin against S. sonnei. Our findings suggest that Stattic has promising potential for development as a new antibiotic or as an adjuvant to antibiotics for infections caused by S. sonnei.


Assuntos
Disenteria Bacilar , Shigella , Humanos , Shigella sonnei , Antibacterianos/farmacologia , Disenteria Bacilar/tratamento farmacológico , Disenteria Bacilar/microbiologia , Ampicilina/farmacologia , Testes de Sensibilidade Microbiana
18.
Cell Stem Cell ; 30(12): 1624-1639.e8, 2023 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-37989316

RESUMO

Reactivating silenced γ-globin expression through the disruption of repressive regulatory domains offers a therapeutic strategy for treating ß-hemoglobinopathies. Here, we used transformer base editor (tBE), a recently developed cytosine base editor with no detectable off-target mutations, to disrupt transcription-factor-binding motifs in hematopoietic stem cells. By performing functional screening of six motifs with tBE, we found that directly disrupting the BCL11A-binding motif in HBG1/2 promoters triggered the highest γ-globin expression. Via a side-by-side comparison with other clinical and preclinical strategies using Cas9 nuclease or conventional BEs (ABE8e and hA3A-BE3), we found that tBE-mediated disruption of the BCL11A-binding motif at the HBG1/2 promoters triggered the highest fetal hemoglobin in healthy and ß-thalassemia patient hematopoietic stem/progenitor cells while exhibiting no detectable DNA or RNA off-target mutations. Durable therapeutic editing by tBE persisted in repopulating hematopoietic stem cells, demonstrating that tBE-mediated editing in HBG1/2 promoters is a safe and effective strategy for treating ß-hemoglobinopathies.


Assuntos
Edição de Genes , Hemoglobinopatias , Humanos , Hemoglobina Fetal/genética , Hemoglobina Fetal/metabolismo , gama-Globinas/genética , gama-Globinas/metabolismo , Sistemas CRISPR-Cas , Mutação/genética , Hemoglobinopatias/genética , Hemoglobinopatias/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Fatores de Transcrição/metabolismo
19.
World J Oncol ; 14(6): 464-475, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38022411

RESUMO

Background: Proteasome inhibitors, such as bortezomib, have demonstrated efficacy in the therapeutic management of multiple myeloma (MM). However, it is important to note that these inhibitors also elicit endoplasmic reticulum stress, which subsequently triggers the unfolded protein response (UPR) and autophagy, which have been shown to facilitate the survival of tumor cells. The disruption of the circadian clock is considered a characteristic feature of cancer. However, how disrupted circadian clock intertwines with tumor metabolism and drug resistance is not clearly clarified. This work explores the antitumor effectiveness of bortezomib and the circadian clock agonist SR9009, elucidating their impact on glucose-regulated protein 78 (GRP78), the autophagy process, and lipogenesis. Methods: The antitumor effects of bortezomib and SR9009 were evaluated using human MM cell lines (RPMI8226 and U266) in vitro and in vivo nonobese diabetic/severe combined immunodeficient (NOD/SCID) murine xenograft MM model. The assessment of cell viability was conducted using the cell counting kit-8 (CCK8) method, whereas the measurement of cell proliferation was performed with the inclusion of EdU (5-ethynyl-2'-deoxyuridine). Apoptosis was assessed by flow cytometry. The cells were transduced using adenovirus-tf-LC3, which was labeled with dual fluorescence. Subsequently, confocal imaging was employed to observe and examine the autophagosomes. REV-ERBα knockdown leads to upregulation of ATG5 and BENC1 at the protein level with immunoblot. Changes in the expression levels of GRP78, LC3, stearoyl-CoA desaturase 1 (SCD1), and fatty acid synthase (FASN) were assessed through the utilization of quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting. Results: Our results showed that both bortezomib and circadian clock REV-ERBs agonist SR9009 decreased MM viability, proliferation rate and induced an apoptotic response in a dose-dependent manner in vitro. However, the two differ greatly in their mechanisms of action. Bortezomib upregulated GRP78 and autophagy LC3, while circadian clock agonist SR9009 inhibited GRP78 and autophagy LC3. Combined SR9009 with bortezomib induced synergistic cytotoxicity against MM cells. REV-ERBα knockdown lead to upregulation of ATG5, BENC1 and significant upregulation of FASN, and SCD1. Mechanically, SR9009 inhibited the core autophagy gene ATG5 and BECN1, and two essential enzymes for de novo lipogenesis FASN and SCD1. SR9009 had synergistic effect with bortezomib and slowed down murine xenograft models of human MM tumor growth in vivo. Conclusions: Taken together, these results demonstrated that the circadian clock component REV-ERBs agonist SR9009 could inhibit GRP78-induced autophagy and de novo lipogenesis processes and had a synergistic effect with proteasome inhibitors in both in vitro and in vivo models of MM. Our findings shed light on how a disrupted circadian clock interacts with metabolic mechanisms to shape proteasome inhibitor drug resistance and suggest that SR9009 may be able to overcome the inherent drug resistance of proteasome inhibitors.

20.
Appl Environ Microbiol ; 89(10): e0118423, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37796010

RESUMO

Outer membrane vesicle (OMV)-delivered Pseudomonas quinolone signal (PQS) plays a critical role in cell-cell communication in Pseudomonas aeruginosa. However, the functions and mechanisms of membrane-enclosed PQS in interspecies communication in microbial communities are not clear. Here, we demonstrate that PQS delivered by both OMVs from P. aeruginosa and liposome reduces the competitiveness of Burkholderia cenocepacia, which usually shares the same niche in the lungs of cystic fibrosis patients, by interfering with quorum sensing (QS) in B. cenocepacia through the LysR-type regulator ShvR. Intriguingly, we found that ShvR regulates the production of the QS signals cis-2-dodecenoic acid (BDSF) and N-acyl homoserine lactone (AHL) by directly binding to the promoters of signal synthase-encoding genes. Perception of PQS influences the regulatory activity of ShvR and thus ultimately reduces QS signal production and virulence in B. cenocepacia. Our findings provide insights into the interspecies communication mediated by the membrane-enclosed QS signal among bacterial species residing in the same microbial community.IMPORTANCEQuorum sensing (QS) is a ubiquitous cell-to-cell communication mechanism. Previous studies showed that Burkholderia cenocepacia mainly employs cis-2-dodecenoic acid (BDSF) and N-acyl homoserine lactone (AHL) QS systems to regulate biological functions and virulence. Here, we demonstrate that Pseudomonas quinolone signal (PQS) delivered by outer membrane vesicles from Pseudomonas aeruginosa or liposome attenuates B. cenocepacia virulence by targeting the LysR-type regulator ShvR, which regulates the production of the QS signals BDSF and AHL in B. cenocepacia. Our results not only suggest the important roles of membrane-enclosed PQS in interspecies and interkingdom communications but also provide a new perspective on the use of functional nanocarriers loaded with QS inhibitors for treating pathogen infections.


Assuntos
Burkholderia cenocepacia , Percepção de Quorum , Humanos , Percepção de Quorum/genética , Virulência/genética , Acil-Butirolactonas/metabolismo , Lipossomos/metabolismo , Proteínas de Bactérias/genética , Burkholderia cenocepacia/genética , Pseudomonas aeruginosa/metabolismo , Regulação Bacteriana da Expressão Gênica
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