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2.
Appl Opt ; 63(8): 1962-1970, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38568636

RESUMO

In this paper, a dual-band terahertz metamaterial sensor based on aluminum and silicon is proposed and simulated. The aluminum surface, which is deposited on a silicon substrate, is made of a C-shaped frame resonator, a rectangular beam, and a cross. The device is insensitive to the change of incident angle in the range of 0°-30°, which shows the great transmission stability of the sensor. By examining the resonance frequency shift, it is shown that 98.3 and 237.5 GHz/RIU refractive index sensitivity can be obtained near 1.76 and 2.404 THz transmission dips of the proposed structure, respectively. The two dips can be used to sense analytes in different refractive index ranges, respectively. For Dip 1 at 1.76 THz, the range is 1.0-1.6. For Dip 2 at 2.404 THz, the range is 1.6-2.0. Different from traditional multi-band metamaterial sensors, two dips generated by the proposed device can measure continuous and non-multiplexed refractive index ranges, respectively. Because the resonance frequencies of matters are different, such a characteristic enables the device to measure different types of analyte using the appropriate resonant peak. A central-relief design is then proposed based on perturbation theory to further improve its sensing performance. The aluminum cross is covered by polyimide, which can interfere with the scattering field on the metal surface and affect the transmission results. For both transmission dips, the optimized structure realizes higher sensitivities of 111.7 GHz/RIU and 262.5 GHz/RIU, respectively. More significantly, the optimized structure also has the characteristic of a wide and non-multiplexed refractive index range. In addition, the effects of analyte thickness and polyimide layer thickness on sensor performance are also discussed. The proposed structure opens up new prospects in the design of multiple-band terahertz metamaterial sensors. It can also meet the sensing needs of biomedical, environmental monitoring, and industrial manufacturing.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38577897

RESUMO

BACKGROUND: Trio exome sequencing can be used to investigate congenital abnormalities identified on pregnancy ultrasound, but its use in an Australian context has not been assessed. AIMS: Assess clinical outcomes and changes in management after expedited genomic testing in the prenatal period to guide the development of a model for widespread implementation. MATERIALS AND METHODS: Forty-three prospective referrals for whole exome sequencing, including 40 trios (parents and pregnancy), two singletons and one duo were assessed in a tertiary hospital setting with access to a state-wide pathology laboratory. Diagnostic yield, turn-around time (TAT), gestational age at reporting, pregnancy outcome, change in management and future pregnancy status were assessed for each family. RESULTS: A clinically significant genomic diagnosis was made in 15/43 pregnancies (35%), with an average TAT of 12 days. Gestational age at time of report ranged from 16 + 5 to 31 + 6 weeks (median 21 + 3 weeks). Molecular diagnoses included neuromuscular and skeletal disorders, RASopathies and a range of other rare Mendelian disorders. The majority of families actively used the results in pregnancy decision making as well as in management of future pregnancies. CONCLUSIONS: Rapid second trimester prenatal genomic testing can be successfully delivered to investigate structural abnormalities in pregnancy, providing crucial guidance for current and future pregnancy management. The time-sensitive nature of this testing requires close laboratory and clinical collaboration to ensure appropriate referral and result communication. We found the establishment of a prenatal coordinator role and dedicated reporting team to be important facilitators. We propose this as a model for genomic testing in other prenatal services.

4.
Front Oncol ; 14: 1345576, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38577327

RESUMO

Objective: To evaluate the value of a nomogram combined MRI Diffusion Weighted Imaging (DWI) and clinical features to predict the treatment response of Neoadjuvant Chemotherapy (NAC) in patients with osteosarcoma. Methods: A retrospective analysis was conducted on 209 osteosarcoma patients admitted into two bone cancer treatment centers (133 males, 76females; mean age 16.31 ± 11.42 years) from January 2016 to January 2022. Patients were classified as pathological good responders (pGRs) if postoperative histopathological examination revealed ≥90% tumor necrosis, and non-pGRs if <90%. Their clinical features were subjected to univariate and multivariate analysis, and features with statistically significance were utilized to construct a clinical signature using machine learning algorithms. Apparent diffusion coefficient (ADC) values pre-NAC (ADC 0) and post two chemotherapy cycles (ADC 1) were recorded. Regions of interest (ROIs) were delineated from pre-treatment DWI images (b=1000 s/mm²) for radiomic features extraction. Variance thresholding, SelectKBest, and LASSO regression were used to select features with strong relevance, and three machine learning models (Logistic Regression, RandomForest and XGBoost) were used to construct radiomics signatures for predicting treatment response. Finally, the clinical and radiomics signatures were integrated to establish a comprehensive nomogram model. Predictive performance was assessed using ROC curve analysis, with model clinical utility appraised through AUC and decision curve analysis (DCA). Results: Of the 209patients, 51 (24.4%) were pGRs, while 158 (75.6%) were non-pGRs. No significant ADC1 difference was observed between groups (P>0.05), but pGRs had a higher ADC 0 (P<0.01). ROC analysis indicated an AUC of 0.681 (95% CI: 0.482-0.862) for ADC 0 at the threshold of ≥1.37×10-3 mm²/s, achieving 74.7% sensitivity and 75.7% specificity. The clinical and radiomics models reached AUCs of 0.669 (95% CI: 0.401-0.826) and 0.768 (95% CI: 0.681-0.922) respectively in the test set. The combined nomogram displayed superior discrimination with an AUC of 0.848 (95% CI: 0.668-0.951) and 75.8% accuracy. The DCA suggested the clinical utility of the nomogram. Conclusion: The nomogram based on combined radiomics and clinical features outperformed standalone clinical or radiomics model, offering enhanced accuracy in evaluating NAC response in osteosarcoma. It held significant promise for clinical applications.

5.
Comput Biol Med ; 174: 108450, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38608325

RESUMO

Magnetic resonance imaging (MRI) is a non-invasive medical imaging technique that provides high-resolution 3D images and valuable insights into human tissue conditions. Even at present, the refinement of denoising methods for MRI remains a crucial concern for improving the quality of the images. This study aims to improve the prefiltered rotationally invariant non-local principal component analysis (PRI-NL-PCA) algorithm. We relaxed the original restrictions using particle swarm optimization to determine optimal parameters for the PCA part of the original algorithm. In addition, we adjusted the prefiltered rotationally invariant non-local mean (PRI-NLM) part by traversing the signal intensities of voxels instead of their spatial positions to reduce duplicate calculations and expand the search volume to the whole image when estimating voxels' signal intensities. The new method demonstrated superior denoising performance compared to the original approach. Moreover, in most cases, the new algorithm ran faster. Furthermore, our proposed method can also be applied to process Gaussian noise in natural images and has the potential to enhance other NLM-based denoising algorithms.

6.
Sci Total Environ ; 927: 172468, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38615762

RESUMO

Aqueous trivalent manganese [Mn(III)], an important reactive intermediate, is ubiquitous in natural surface water containing humic acid (HA). However, the effect of low-molecular-weight organic acids (LMWOAs) on the formation, stability and reactivity of Mn(III) intermediate is still unknown. In this study, six LMWOAs, including oxalic acid (Oxa), salicylic acid (Sal), catechol (Cat), caffeic acid (Caf), gallic acid (Gal) and ethylene diamine tetraacetic acid (EDTA), were selected to investigate the effects of LMWOAs on the degradation of BPA induced by in situ formed Mn(III)-L in the HA/Mn(II) system under light irradiation. The chromophoric constituents of HA could absorb light radiation and generate superoxide radical to promote the oxidation of Mn(II) to form Mn(III), which was further involved in transformation of BPA. Our results implied that different LMWOAs did significantly impact on Mn(III) production and its degradation of BPA due to their different functional group. EDTA, Oxa and Sal extensively increased the Mn(III) concentration from 50 to 100 µM compared to the system without LMWOAs, following the order of EDTA > Oxa > Sal, and also enhanced the degradation of BPA with the similar patterns. In contrast, Cat, Caf and Gal had an inhibitory effect on the formation of Mn(III), which is likely because they consumed the superoxide radicals generated from irradiated HA, resulting in the inhibition of Mn(II) oxidation and further BPA removal. The product identification and theoretical calculation indicated that a single electron transfer process occurred between Mn(III)-L and BPA, forming BPA radicals and subsequent self-coupling products. Our results demonstrated that the LMWOAs with different structures could alter the cycling process of Mn via complexation and redox reactions, which would provide new implications for the removal of organic pollutants in surface water.

7.
J Colloid Interface Sci ; 667: 91-100, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38621335

RESUMO

The development of efficient and multifunctional sonosensitizers is crucial for enhancing the efficacy of sonodynamic therapy (SDT). Herein, we have successfully constructed a CoOx-loaded amorphous metal-organic framework (MOF) UIO-66 (A-UIO-66-CoOx) sonosensitizer with excellent catalase (CAT)- and glutathione-oxidase (GSH-OXD)-like activities. The A-UIO-66-CoOx exhibits a 2.6-fold increase in singlet oxygen (1O2) generation under ultrasound (US) exposure compared to crystalline UIO-66 sonosensitizer, which is attributed to its superior charge transfer efficiency and consistent oxygen (O2) supply. Additionally, the A-UIO-66-CoOx composite reduces the expression of glutathione peroxidase (GPX4) by depleting glutathione (GSH) through Co3+ and Co2+ valence changes. The high levels of highly cytotoxic 1O2 and deactivation of GPX4 can lead to lethal lipid peroxidation, resulting in concurrent apoptosis and ferroptosis. Both in vitro and vivo tumor models comprehensively confirmed the enhanced SDT antitumor effect using A-UIO-66-CoOx sonosensitizer. Overall, this study emphasizes the possibility of utilizing amorphization engineering to improve the effectiveness of MOFs-based sonosensitizers for combined cancer therapies.

8.
J Agric Food Chem ; 72(14): 8140-8148, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38563232

RESUMO

Rebaudioside (Reb) M is an important sweetener with high sweetness, but its low content in Stevia rebaudiana and low catalytic capacity of the glycosyltransferases in heterologous microorganisms limit its production. In order to improve the catalytic efficiency of the conversion of stevioside to Reb M by Saccharomyces cerevisiae, several key issues must be resolved including knocking out endogenous hydrolases, enhancing glycosylation, and extending the enzyme catalytic process. Herein, endogenous glycosyl hydrolase SCW2 was knocked out in S. cerevisiae. The glycosylation process was enhanced by screening glycosyltransferases, and UGT91D2 from S. rebaudiana was identified as the optimum glycosyltransferase. The UDP-glucose supply was enhanced by overexpressing UGP1, and co-expressing UGT91D2 and UGT76G1 achieved efficient conversion of stevioside to Reb M. In order to extend the catalytic process, the silencing information regulator 2 (SIR2) which can prolong the growth cycle of S. cerevisiae was introduced. Finally, combining these modifications produced 12.5 g/L Reb M and the yield reached 77.9% in a 5 L bioreactor with 10.0 g/L stevioside, the highest titer from steviol glycosides to Reb M reported to date. The engineered strain could facilitate the industrial production of Reb M, and the strategies provide references for the production of steviol glycosides.


Assuntos
Diterpenos do Tipo Caurano , Stevia , Trissacarídeos , Saccharomyces cerevisiae/genética , Difosfato de Uridina , Hidrolases , Glucosídeos , Glicosiltransferases/genética , Glicosídeos , Folhas de Planta
9.
ISA Trans ; 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38429141

RESUMO

In this paper, the robust adaptive optimal tracking control problem is addressed for the disturbed unmanned helicopter based on the time-varying gain extended state observer (TVGESO) and adaptive dynamic programming (ADP) methods. Firstly, a novel TVGESO is developed to tackle the unknown disturbance, which can overcome the drawback of initial peaking phenomenon in the traditional linear ESO method. Meanwhile, compared with the nonlinear ESO, the proposed TVGESO possesses easier and rigorous stability analysis process. Subsequently, the optimal tracking control issue for the original unmanned helicopter system is transformed into an optimization stabilization problem. By means of the ADP and neural network techniques, the feedforward controller and optimal feedback controller are skillfully designed. Compared with the conventional backstepping approach, the designed anti-disturbance optimal controller can make the unmanned helicopter accomplish the tracking task with less energy. Finally, simulation comparisons demonstrate the validity of the developed control scheme.

10.
J Hepatocell Carcinoma ; 11: 477-488, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38463543

RESUMO

Purpose: Recently, hepatic arterial infusion chemotherapy (HAIC) has also gained popularity for hepatocellular carcinoma (HCC). Several studies have compared HAIC and Transarterial chemoembolization (TACE). However, comparisons between TACE plus HAIC and HAIC are rarely reported. Here, we evaluated the performance of HepaSphere DEB-TACE combined with HAIC (Hepa-HAIC) compared to HAIC in patients with advanced HCC. Patients and Methods: In this retrospective study, we enrolled 167 patients diagnosed with advanced HCC and treated at Peking University Cancer Hospital from May 2018 to May 2022. The cohort comprised 74 patients who received HepaSphere DEB-TACE combined with HAIC-FOLFOX (Hepa-HAIC) and 93 patients who received HAIC-FOLFOX. Over 60% of patients received prior treatments. To avoid selection bias, propensity score matching was applied to the efficacy and safety analyses. The primary endpoints are progression-free survival (PFS) and overall survival (OS); the secondary endpoints include objective response rate (ORR), disease control rate (DCR), and safety. Results: Propensity-matching yielded 48 pairs, and group baselines were almost equal after matching. Median PFS and median OS were both higher in the matched Hepa-HAIC cohort (median PFS: 8.9 vs 5.8 months, p = 0.035; median OS: 22.4 vs 9.5 months, p = 0.027), which was consistent with pre-matching analysis. The ORR in the Hepa-HAIC and HAIC cohorts was 75.0% and 37.5%, respectively; the DCR was 93.8% after Hepa-HAIC and 81.3% after HAIC. There was no treatment-related death. Grade 3-4 ALT elevation was more frequent in the Hepa-HAIC group (33.3% vs 8.3%, p = 0.003), while vomiting was more frequent in the HAIC group (29.2% vs 12.5%, p = 0.084). Conclusion: The Hepa-HAIC group is superior to the HAIC group in metrics of PFS, OS, ORR, and DCR, which indicates the combination of HepaSphere DEB-TACE and HAIC may lead to improved outcomes with a comparable safety profile in advanced HCC.

11.
Drug Chem Toxicol ; : 1-15, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38465444

RESUMO

Alkaloids are naturally occurring compounds with complex structures found in natural plants. To further improve the understanding of plant alkaloids, this review focuses on the classification, toxicity and mechanisms of action, providing insight into the occurrence of alkaloid-poisoning events and guiding the safe use of alkaloids in food, supplements and clinical applications. Based on their chemical structure, alkaloids can be divided into organic amines, diterpenoids, pyridines, isoquinolines, indoles, pyrrolidines, steroids, imidazoles and purines. The mechanisms of toxicity of alkaloids, including neurotoxicity, hepatoxicity, nephrotoxicity, cardiotoxicity and cytotoxicity, have also been reviewed. Some cases of alkaloid poisoning have been introduced when used as food or clinically, including accidental food poisoning, excessive consumption, and poisoning caused by the improper use of alkaloids in a clinical setting, and the importance of safety evaluation was illustrated. This review summarizes the toxicity and mechanism of action of alkaloids and provides evidence for the need for the safe use of alkaloids in food, supplements and clinical applications.

12.
Phys Chem Chem Phys ; 26(11): 8993-9004, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38440799

RESUMO

This paper proposes a simulated design for a versatile terahertz absorber that can be actively tuned. The absorber utilizes the unique tuning capabilities of graphene and vanadium dioxide, enabling it to alternate between ultra-broadband absorption, broadband absorption, and almost complete reflection. In the metallic phase of vanadium dioxide, coupled with a graphene Fermi level at 0 eV, the absorber achieves ultra-broadband absorption. This spans an extensive frequency range from 3.85 THz to 9.73 THz, exhibiting an absorption rate surpassing 90%. As we shift to the insulating phase of vanadium dioxide and adjust the graphene Fermi level to 1 eV, the absorber operates in a broadband absorption mode. This mode spans 2.98 THz to 4.63 THz, demonstrating an absorption rate exceeding 90%. In the insulating state of vanadium dioxide with a graphene Fermi level at 0 eV, the absorber metamorphoses into a nearly total reflector. Its maximum absorption rate is a mere 0.52%. The unique adjustability of vanadium dioxide and graphene independently enables the fine-tuning of absorption rates for both ultra-broadband and broadband absorption without encountering interference. Additionally, thanks to the central symmetry inherent in the proposed structure, the absorber exhibits insensitivity to alterations in polarization angles and remains stable under a broad range of incident angles. With these benefits, the absorber shows promising potential for applications in electromagnetic stealth, wireless communication, and so on.

13.
Pharm Res ; 41(4): 807-817, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38443629

RESUMO

OBJECTIVE: Current gene therapy of inherited retinal diseases is achieved mainly by subretinal injection, which is invasive with severe adverse effects. Intravitreal injection is a minimally invasive alternative for gene therapy of inherited retinal diseases. This work explores the efficacy of intravitreal delivery of PEGylated ECO (a multifunctional pH-sensitive amphiphilic amino lipid) plasmid DNA (pGRK1-ABCA4-S/MAR) nanoparticles (PEG-ELNP) for gene therapy of Stargardt disease. METHODS: Pigmented Abca4-/- knockout mice received 1 µL of PEG-ELNP solution (200 ng/uL, pDNA concentration) by intravitreal injections at an interval of 1.5 months. The expression of ABCA4 in the retina was determined by RT-PCR and immunohistochemistry at 6 months after the second injection. A2E levels in the treated eyes and untreated controls were determined by HPLC. The safety of treatment was monitored by scanning laser ophthalmoscopy and electroretinogram (ERG). RESULTS: PEG-ELNP resulted in significant ABCA4 expression at both mRNA level and protein level at]6 months after 2 intravitreal injections, and a 40% A2E accumulation reduction compared with non-treated controls. The PEG-ELNP also demonstrated excellent safety as shown by scanning laser ophthalmoscopy, and the eye function evaluation from electroretinogram. CONCLUSIONS: Intravitreal delivery of the PEG-ELNP of pGRK1-ABCA4-S/MAR is a promising approach for gene therapy of Stargardt Disease, which can also be a delivery platform for gene therapy of other inherited retinal diseases.


Assuntos
Nanopartículas , Retina , Camundongos , Animais , Doença de Stargardt/genética , Doença de Stargardt/metabolismo , Doença de Stargardt/terapia , Retina/metabolismo , Terapia Genética/métodos , Plasmídeos/genética , DNA/metabolismo , Camundongos Knockout , Polietilenoglicóis/metabolismo , Injeções Intravítreas , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo
14.
Vaccine ; 42(10): 2707-2715, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38503663

RESUMO

Avian pathogenic Escherichia coli (APEC) is primarily responsible for causing septicemia, pneumonitis, peritonitis, swollen head syndrome, and salpingitis in poultry, leading to significant losses in the poultry sector, particularly within the broiler industry. The removal of the lpxL and lpxM genes led to an eightfold decrease in the endotoxin levels of wild APEC strains. In this study, mutant strains of lpxL/lpxM and their O1, O2, and O78 wild-type strains were developed for an inactivated vaccine (referred to as the mutant vaccine and the wild-type vaccine, respectively), and the safety and effectiveness of these two prototype vaccines were assessed in white Leghorn chickens. Findings indicated that chickens immunized with the mutant vaccine showed a return of appetite sooner post-immunization and experienced earlier disappearance of nodules at the injection site compared to those immunized with the wild-type vaccine. Pathological examinations revealed that lesions were still present in the liver, lung, and injection site in chickens vaccinated with the wild-type vaccine 14 days post-vaccination (dpv), whereas no lesions were found in chickens vaccinated with the mutant vaccine at 14 dpv. There were no significant differences in antibody levels on the challenge day or in mortality or lesion scores between challenged birds immunized with either the mutant vaccine or the wild-type vaccine at the same dose. In this study, the safety of a single dose or overdose of the mutant vaccine and its efficacy at one dose were evaluated in broilers, and the results showed that the mutant vaccine had no adverse effects on or protected vaccinated broilers from challenge with the APEC O1, O2, or O78 strains. These results demonstrated that the mutant polyvalent inactivated vaccine is a competitive candidate against APEC O1, O2, and O78 infection compared to the wild-type vaccine.


Assuntos
Infecções por Escherichia coli , Vacinas contra Escherichia coli , Doenças das Aves Domésticas , Animais , Escherichia coli/genética , Galinhas , Infecções por Escherichia coli/prevenção & controle , Infecções por Escherichia coli/veterinária , Vacinas de Produtos Inativados/efeitos adversos
15.
J Hazard Mater ; 469: 134067, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38513441

RESUMO

High-performance antibodies are core reagents for highly sensitive immunoassays. Herein, based on a novel hapten, a hybridoma secreting the high-affinity anti-ethirimol monoclonal antibody (mAb-14G5F6) was isolated with an IC50 value of 1.35 µg/L and cross-reactivity below 0.20% for 13 analogs. To further address the challenge of hybridoma preservation and antibody immortalization, a recombinant full-length antibody (rAb-14G5F6) was expressed using the HEK293(F) expression system based on the mAb-14G5F6 gene. The affinity, specificity, and tolerance of rAb-14G5F6, as characterized by indirect competitive enzyme-linked immunosorbent assay and noncompetitive surface plasmon resonance, exhibited high concordance with those of mAb-14G5F6. Further immunoassays based on rAb-14G5F6 were developed for irrigation water and strawberry fruit with limits of detection of 0.0066 and 0.036 mg/kg, respectively, recoveries of 80100%, and coefficients of variation below 10%. Furthermore, homology simulation and molecular docking revealed that GLU(L40), GLY(L107), GLY(H108), and ASP(H114) play important roles in forming hydrogen bonds and pi-anion ionic bonds between rAb-14G5F6 and ethirimol, resulting in the high specificity and affinity of rAb-14G5F6 for ethirimol, with a KD of 5.71 × 10-10 mol/L. Overall, a rAb specific for ethirimol was expressed successfully in this study, laying the groundwork for rAb-based immunoassays for monitoring fungicide residues in agricultural products and the environment.


Assuntos
Anticorpos Monoclonais , Frutas , Pirimidinonas , Humanos , Ensaio de Imunoadsorção Enzimática , Frutas/química , Água/análise , Simulação de Acoplamento Molecular , Células HEK293 , Proteínas Recombinantes/genética
16.
Proc Natl Acad Sci U S A ; 121(14): e2217019121, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38547062

RESUMO

Mitochondria constantly fuse and divide for mitochondrial inheritance and functions. Here, we identified a distinct type of naturally occurring fission, tail-autotomy fission, wherein a tail-like thin tubule protrudes from the mitochondrial body and disconnects, resembling autotomy. Next, utilizing an optogenetic mitochondria-specific mechanostimulator, we revealed that mechanical tensile force drives tail-autotomy fission. This force-induced fission involves DRP1/MFF and endoplasmic reticulum tubule wrapping. It redistributes mitochondrial DNA, producing mitochondrial fragments with or without mitochondrial DNA for different fates. Moreover, tensile force can decouple outer and inner mitochondrial membranes, pulling out matrix-excluded tubule segments. Subsequent tail-autotomy fission separates the matrix-excluded tubule segments into matrix-excluded mitochondrial-derived vesicles (MDVs) which recruit Parkin and LC3B, indicating the unique role of tail-autotomy fission in segregating only outer membrane components for mitophagy. Sustained force promotes fission and MDV biogenesis more effectively than transient one. Our results uncover a mechanistically and functionally distinct type of fission and unveil the role of tensile forces in modulating fission and MDV biogenesis for quality control, underscoring the heterogeneity of fission and mechanoregulation of mitochondrial dynamics.


Assuntos
Proteínas de Membrana , Dinâmica Mitocondrial , Proteínas de Membrana/genética , Proteínas Mitocondriais/genética , Mitocôndrias/genética , DNA Mitocondrial , Controle de Qualidade , Dinaminas/genética
17.
Foodborne Pathog Dis ; 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38551156

RESUMO

Vibrio vulnificus is a hazardous foodborne pathogen responsible for approximately 95% of seafood-related deaths. This highlights the urgent requirement for specialized detection tools to be developed and used by food enterprises and food safety authorities. The DETECTR (DNA endonuclease targeted CRISPR trans reporter) system that combines CRISPR/Cas and recombinase polymerase amplification (RPA) has been utilized to develop a molecular detection assay for V. vulnificus. However, because the incompatibility between RPA and Cas12a cleavage has not been addressed, it is a two-step assay that lacks convenience and presents contamination risk. Here, we developed a one-step RPA-CRISPR assay for V. vulnificus using a special crRNA targeting a sequence with a suboptimal protospacer adjacent motif (PAM). The entire assay, conducted at 37°C, takes only 40-60 min, yields results visualized under blue light, and exhibits exceptional specificity and sensitivity (detecting 4 pathogen genome copies per reaction). This study offers a valuable tool for detecting V. vulnificus, aiding in foodborne infection prevention, and exemplifies one-step RPA-CRISPR assays managing Cas-cleavage activity through PAM adjustments.

18.
Gastroenterology ; 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38492894

RESUMO

BACKGROUND & AIMS: Because pancreatic cancer responds poorly to chemotherapy and immunotherapy, it is necessary to identify novel targets and compounds to overcome resistance to treatment. METHODS: This study analyzed genomic single nucleotide polymorphism sequencing, single-cell RNA sequencing, and spatial transcriptomics. Ehf-knockout mice, KPC (LSL-KrasG12D/+, LSL-Trp53R172H/+ and Pdx1-Cre) mice, CD45.1+ BALB/C nude mice, and CD34+ humanized mice were also used as subjects. Multiplexed immunohistochemistry and flow cytometry were performed to investigate the proportion of tumor-infiltrated C-X-C motif chemokine receptor 2 (CXCR2)+ neutrophils. In addition, multiplexed cytokines assays and chromatin immunoprecipitation assays were used to examine the mechanism. RESULTS: The TP53 mutation-mediated loss of tumoral EHF increased the recruitment of CXCR2+ neutrophils, modulated their spatial distribution, and further induced chemo- and immunotherapy resistance in clinical cohorts and preclinical syngeneic mice models. Mechanistically, EHF deficiency induced C-X-C motif chemokine ligand 1 (CXCL1) transcription to enhance in vitro and in vivo CXCR2+ neutrophils migration. Moreover, CXCL1 or CXCR2 blockade completely abolished the effect, indicating that EHF regulated CXCR2+ neutrophils migration in a CXCL1-CXCR2-dependent manner. The depletion of CXCR2+ neutrophils also blocked the in vivo effects of EHF deficiency on chemotherapy and immunotherapy resistance. The single-cell RNA-sequencing results of PDAC treated with Nifurtimox highlighted the therapeutic significance of Nifurtimox by elevating the expression of tumoral EHF and decreasing the weightage of CXCL1-CXCR2 pathway within the microenvironment. Importantly, by simultaneously inhibiting the JAK1/STAT1 pathway, it could significantly suppress the recruitment and function of CXCR2+ neutrophils, further sensitizing PDAC to chemotherapy and immunotherapies. CONCLUSIONS: The study demonstrated the role of EHF in the recruitment of CXCR2+ neutrophils and the promising role of Nifurtimox in sensitizing pancreatic cancer to chemotherapy and immunotherapy.

19.
Angew Chem Int Ed Engl ; : e202402093, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38438306

RESUMO

Lead-based radicals in the oxidation state of +1 are elusive species and are highly challenging to isolate in the condensed phase. In this study, we present the synthesis and characterization of the first isolable free plumbylyne radical 2 bearing a one-coordinate Pb(I) atom. It reacts with an N-heterocyclic carbene (NHC) to afford a two-coordinate NHC-ligated Pb(I) radical 3. 2 and 3 represent the first isolable Pb(I)-based radicals. Theoretical calculations and electron paramagnetic resonance analysis revealed that the unpaired electron mainly resides at the Pb 6p orbital in both radicals. Owing to the unique one-coordinate nature of the Pb atom in 2, it possesses two-fold orbital pseudo-degeneracy and substantial unquenched orbital angular momentum, and exhibits hitherto strongest g-factor anisotropy (gx,y,z=1.496, 1.166, 0.683) amongst main group radicals. Preliminary investigations into the reactivity of 2 unveiled its Pb-centered radical nature, and plumbylenes were isolated as products.

20.
Adv Mater ; : e2314130, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38428436

RESUMO

Radiative cooling technology is well known for its subambient temperature cooling performance under sunlight radiation. However, the intrinsic maximum cooling power of radiative cooling limits the performance when the objects meet the thermal shock. Here, a dual-function strategy composed of radiative cooling and latent heat storage simultaneously enabling the efficient subambient cooling and high-efficiency thermal-shock resistance performance is proposed. The electrospinning and absorption-pressing methods are used to assemble the dual-function cooler. The high sunlight reflectivity and high mid-infrared emissivity of radiative film allow excellent subambient temperature of 5.1 °C. When subjected the thermal shock, the dual-function cooler demonstrates a pinning effect of huge temperature drop of 39 °C and stable low-temperature level by isothermal heat absorption compared with the traditional radiative cooler. The molten phase change materials provide the heat-time transfer effect by converting thermal-shock heat to the delayed preservation. This strategy paves a powerful way to protect the objects from thermal accumulation and high-temperature damage, expanding the applications of radiative cooling and latent heat storage technologies.

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