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1.
Small ; : e2405505, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39358943

RESUMO

Extracellular vesicles (EVs) are particles released from cells that facilitate intercellular communication and have tremendous diagnostic and therapeutic potential. Bulk assays lack the sensitivity to detect rare EV subsets relevant to disease, and while single EV analysis techniques remedy this, they are often undermined by complicated detection schemes and prohibitive instrumentation. To address these issues, a microfluidic technique for EV characterization called "catch and display for liquid biopsy (CAD-LB)" is proposed. In this method, minimally processed samples are pipette-injected and fluorescently labeled EVs are captured in the nanopores of an ultrathin membrane.  This enables the rapid assessment of EV number and biomarker colocalization by light microscopy. Here, nanoparticles are used to define the accuracy and dynamic range for counting and colocalization. The same assessments are then made for purified EVs and for unpurified EVs in plasma. Biomarker detection is validated using CD9 and Western blot analysis to confirm that CAD-LB accurately reports relative protein expression levels. Using unprocessed conditioned media, CAD-LB captures the known increase in EV-associated ICAM-1 following endothelial cell cytokine stimulation. Finally, to demonstrate CAD-LB's clinical potential, EV biomarkers indicative of immunotherapy responsiveness are successfully detected in the plasma of bladder cancer patients treated with immune checkpoint blockade.

2.
Micromachines (Basel) ; 15(9)2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39337781

RESUMO

High-strength aluminium alloys are prone to porosity and cracking during laser-based powder bed fusion of metals (PBF-LB/M) due to the complex solidification behaviour, thus limiting the preparation of high-quality aluminium alloys. In order to effectively reduce the defect formation, this study investigated the influence mechanism of different process parameters on the formation of porosity and cracks in Al-Zn-Mg-Cu alloys in the PBF-LB/M process by combining experimental and numerical simulation. The degree of influence of the process parameters on the temperature field and the temperature field on the defect formation was also quantified using path analysis. The results show that modulation of the process parameters can effectively reduce the formation of cracks and pores, although it is difficult to eliminate them. The melt pool temperature has a significant effect on the formation of porosity, and the temperature gradient has a significant effect on the formation of cracks. The degree of influence of laser power on the melt pool temperature and temperature gradient was greater than that of scanning speed, with values of 0.980 and 0.989, respectively. Therefore, the priority of modulating the laser power is higher than that of scanning speed in order to reduce the formation of defects more effectively.

3.
Methods Enzymol ; 704: 39-58, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39300656

RESUMO

Non-heme iron oxygenases constitute a versatile enzyme family that is crucial for incorporating molecular oxygen into diverse biomolecules. Despite their importance, only a limited number of these enzymes have been structurally and functionally characterized. Surprisingly, there remains a significant gap in understanding how these enzymes utilize a typical architecture and reaction mechanism to catalyze a wide range of reactions. Improving our understanding of these catalysts holds promise for advancing both fundamental enzymology and practical applications. This chapter aims to outline methods for heterologous expression, enzyme preparation, in vitro enzyme assays, and crystallization of biphenyl dioxygenase, phthalate dioxygenase and terephthalate dioxygenase. These enzymes catalyze the dihydroxylation of biphenyl, phthalate and terephthalate molecules, serving as a model for functional and structural analysis of other non-heme iron oxygenases.


Assuntos
Compostos de Bifenilo , Cristalização , Ácidos Ftálicos , Ácidos Ftálicos/química , Ácidos Ftálicos/metabolismo , Compostos de Bifenilo/química , Cinética , Cristalização/métodos , Dioxigenases/química , Dioxigenases/metabolismo , Dioxigenases/genética , Ferro/química , Ferro/metabolismo , Cristalografia por Raios X/métodos , Ensaios Enzimáticos/métodos , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Oxigenases
4.
J Food Sci Technol ; 61(10): 1874-1883, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39285985

RESUMO

The present study aimed to produce frozen dessert containing plant-based milk (almond, hazelnut, and lupine) and the probiotic Lb. acidophilus bacteria and to evaluate the chemical, microbiological and sensory properties during the 90 day-storage. Frozen dessert antioxidant capacity at day 0 and 90 of evaluation and changes in the phenolic compounds based on variations between different species were significant (p < 0.05). The differences in Lb. acidophilus counts between storage days were significant and values ranged from 4.15-8.99 log CFU/mL on the first day of storage to 3.61-7.06 at the end of the storage. Regarding the results of general acceptability in sensory evaluation, the highest color, taste and aroma scores was determined on day 0 in the hazelnut-lupine milk frozen dessert sample whereas the lowest was determined on day 30 in the almond-lupine milk frozen dessert sample. The samples with the highest antioxidant capacity were found on day 90 day in lupine frozen dessert (87.28 ± 0.007 mM) whereas the samples with the lowest antioxidant capacity were found on day 0 in the almond-hazelnut-lupine frozen dessert (18.83 ± 4.56 mM). Plant-based milk is considered suitable for the main ingredients in ice cream production, due to its health benefits its potential to be consumed as frozen dessert. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-024-05964-8.

5.
Materials (Basel) ; 17(17)2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39274605

RESUMO

During the laser-based directed energy deposition (DED-LB) processing, a WC-12Co composite coating with high hardness and strong wear resistance was successfully prepared on a 316L stainless steel substrate by adopting a high-precision coaxial powder feeding system using a spherical WC-12Co composite powder, which showed a large number of dendritic carbides and herringbone planar crystals on the substrate-binding interface. The influences of laser power on microstructural and mechanical properties (e.g., hardness, friction resistance) of WC-12Co composite surfaces were investigated. The results show that laser power has a significant effect on determining the degree of Co phase melting around the WC particles and the adhesion strength between the matrix and the coating. Lower laser power does not meet the melting requirements of WC particles, thus weakening the molding quality of the composite coating. At high laser power, it is possible to dissolve the WC particles and melt the metal powder between the particles, thus improving the material properties. The laser power increased from 700 W to 1000 W and the average hardness of the coating surface gradually increased from 1166.33 HV to 1395.70 HV, which is about 4-5 times higher than the average hardness of the substrate (about 281.76 HV). In addition, the coatings deposited at 1000 W showed better wear resistance. This work shows that the processing parameters during laser-directed energy deposition can be optimized to prepare WC-12Co composite coatings with excellent mechanical properties.

6.
Materials (Basel) ; 17(17)2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39274774

RESUMO

This study investigates the microstructural effects of process parameters on Ti6Al4V alloy produced via powder bed fusion (PBF) using laser beam melting (LB/M) technology. The research focuses on how variations in laser power, exposure velocity, and hatching distance influence the final material's porosity, microhardness, and microstructure. To better understand the relationships between process parameters, energy density, and porosity, a simple mathematical model was developed. The microstructure of the alloy was analyzed in the YZ plane using a confocal microscope. The study identified optimal parameters-302.5 W laser power, 990 mm/s exposure velocity, and 0.14 mm hatching distance-yielding the lowest porosity index of 0.005%. The material's average hardness was measured at 434 ± 18 HV0.5. These findings offer valuable insights for optimizing printing parameters to produce high-quality Ti6Al4V components using PBF-LB/M technology, shedding light on the critical relationship between process parameters and the resulting microstructure.

7.
J Virol ; 98(9): e0104724, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39194238

RESUMO

Little is known regarding the molecular mechanisms that highly pathogenic Marburg virus (MARV) utilizes to transcribe and replicate its genome. Previous studies assumed that dephosphorylation of the filoviral transcription factor VP30 supports transcription, while phosphorylated VP30 reduces transcription. Here, we focused on the role of the host protein phosphatase 2A (PP2A) for VP30 dephosphorylation and promotion of viral transcription. We could show that MARV NP interacts with the subunit B56 of PP2A, as previously shown for the Ebola virus, and that this interaction is important for MARV transcription activity. Inhibition of the interaction between PP2A and NP either by mutating the B56 binding motif encoded on NP, or the use of a PP2A inhibitor, induced VP30 hyperphosphorylation, and as a consequence a decrease of MARV transcription as well as viral growth. These results suggest that NP plays a key role in the dephosphorylation of VP30 by recruiting PP2A. Generation of recombinant (rec) MARV lacking the PP2A-B56 interaction motif on NP was not possible suggesting an essential role of PP2A-mediated VP30 dephosphorylation for the MARV replication cycle. Likewise, we were not able to generate recMARV containing VP30 phosphomimetic mutants indicating that dynamic cycles of VP30 de- and rephosphorylation are a prerequisite for an efficient viral life cycle. As the specific binding motifs of PP2A-B56 and VP30 within NP are highly conserved among the filoviral family, our data suggest a conserved mechanism for filovirus VP30 dephosphorylation by PP2A, revealing the host factor PP2A as a promising target for pan-filoviral therapies. IMPORTANCE: Our study elucidates the crucial role of host protein phosphatase 2A (PP2A) in Marburg virus (MARV) transcription. The regulatory subunit B56 of PP2A facilitates VP30 dephosphorylation, and hence transcription activation, via binding to NP. Our results, together with previous data, reveal a conserved mechanism of filovirus VP30 dephosphorylation by host factor PP2A at the NP interface and provide novel insights into potential pan-filovirus therapies.


Assuntos
Marburgvirus , Proteína Fosfatase 2 , Transcrição Gênica , Marburgvirus/fisiologia , Marburgvirus/genética , Marburgvirus/metabolismo , Proteína Fosfatase 2/metabolismo , Proteína Fosfatase 2/genética , Humanos , Fosforilação , Replicação Viral , Células HEK293 , Animais , Interações Hospedeiro-Patógeno , Proteínas Virais/metabolismo , Proteínas Virais/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Doença do Vírus de Marburg/virologia , Doença do Vírus de Marburg/metabolismo , Ligação Proteica , Linhagem Celular
8.
ACS Appl Mater Interfaces ; 16(36): 48438-48447, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39109880

RESUMO

Utilizing softly confined self-assembly at the water surface represents a promising approach for the fabrication of two-dimensional molecular monolayers (2D MMs), which have predominantly been concentrated on amphiphilic organic compounds before. Herein, we introduce a straightforward method termed "water surface-assisted molecular deposition (WSAMD)" to organize nonamphiphilic molecules into dense monolayers with high reproducibility. To underscore the versatility and merit of this methodology in the field of supramolecular electronics, we have successfully fabricated a range of defect-free, uniform semiconducting polymer monolayers, featuring a thickness reflective of molecular architectures. The charge carrier mobility could reach 0.05 cm2 V-1 s-1 for holes and 3.5 × 10-4 cm2 V-1 s-1 for electrons, respectively, in p-type and n-type polymeric monolayers when tested as the active layer in field-effect transistors. Furthermore, in situ polymerization reactions can be exploited to generate conductive monolayers of macromolecules such as polybenzylaniline (PBnANI) and polypyrrole (PPy), where PBnANI monolayers exhibit channel length-dependent conductivity, up to 0.37 S cm-1. The advent of the WSAMD method heralds a significant leap forward in the advancement of molecular 2D materials, catalyzing new avenues of exploration within material chemistry.

9.
Vet Res Commun ; 48(5): 3209-3227, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39150648

RESUMO

The study isolated two strains of intestinal autochthonous bacteria Lactiplantibacillus plantarum1 (MH155966.1) (L1) and Lactiplantibacillus plantarum2 (MH105076.1) (L2) from the Choobdeh Abadan region. The aim of this study was to investigate the effects of different strains of probiotic bacteria on the growth performance, digestive enzyme activity, histopathologic and histomorphometric characterization of the intestine, expression of immune and growth related genes, and evaluate Lates calcarifer resistance against Vibrio alginolyticus. To achieve this, for each treatment 60 L. calcarifer juveniles (75 ± 12 g) were randomly distributed in three fiberglass tanks (300 L) and fed for 45 days. The treatments were established as Diet 1 (control diet); L1 (diet with Lb. plantarum isolated 1); L2 (diet with Lb. plantarum isolated 2) with a bacterial concentration of 1 × 109 CFU/g. Nine fish from each treatment were sampled and examined, after euthanasia. The fish were placed 2 cm from the beginning of the intestine for microscopic sampling of villi height, villi width and thickness of the epithelium, with 3 treatments: The result showed differences in the mean values of total weight were found at the end of the experiment. After 45 days of culture, the fish fed with L1 had higher (P < 0.05) growth performance than the other treatment groups. But at the end of the trial, in L2, the digestive enzyme activities were higher (P < 0.05) than the other treatment groups. The fishes fed diets supplemented with the L2 group, like the digestive enzyme activities test, presented an increase in the thickness of the epithelium of the intestine, and villus height, and villus width were greatest in L2. Fish feeding with L1 and L2 probiotics induced higher transcription levels of interleukin-10 (IL-10), granulocyte-macrophage colony-forming cells (GMCFC), epidermal growth factor (EGF), and Transforming Growth Factor Beta (TGF-ß) genes in the gut, which may correlate with better immune and hematological parameters in these groups. The results of the challenge test revealed that the percentage of survival was significantly higher in L1 (76.2%) and L2 (80.95%) treatments than in the control (P < 0.05). These results indicate that host-derived probiotics (Lb. plantarum) have significant potential as important probiotics to enhance nutrient utilization, Digestive enzymes, and metabolism by increasing the gut surface area of Lates calcarifer juveniles at 45 days of culture.


Assuntos
Ração Animal , Dieta , Doenças dos Peixes , Intestinos , Probióticos , Vibrioses , Vibrio alginolyticus , Animais , Probióticos/farmacologia , Probióticos/administração & dosagem , Doenças dos Peixes/microbiologia , Doenças dos Peixes/imunologia , Doenças dos Peixes/prevenção & controle , Vibrio alginolyticus/fisiologia , Ração Animal/análise , Intestinos/microbiologia , Vibrioses/veterinária , Vibrioses/imunologia , Vibrioses/prevenção & controle , Vibrioses/microbiologia , Dieta/veterinária , Distribuição Aleatória , Resistência à Doença , Perciformes/imunologia , Perciformes/microbiologia
10.
J Transl Med ; 22(1): 727, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39103918

RESUMO

BACKGROUND: Vascular dysregulation is one of the major risk factors of glaucoma, and endothelin-1 (ET-1) may have a role in the pathogenesis of vascular-related glaucoma. Fruit extract from Lycium Barbarum (LB) exhibits anti-ageing and multitarget mechanisms in protecting retinal ganglion cells (RGC) in various animal models. To investigate the therapeutic efficacy of LB glycoproteins (LbGP) in ET-1 induced RGC degeneration, LbGP was applied under pre- and posttreatment conditions to an ET-1 mouse model. Retina structural and functional outcomes were characterised using clinical-based techniques. METHODS: Adult C57BL/6 mice were randomly allocated into four experimental groups, namely vehicle control (n = 9), LbGP-Pretreatment (n = 8), LbGP-Posttreatment (day 1) (n = 8) and LbGP-Posttreatment (day 5) (n = 7). Oral administration of LbGP 1 mg/Kg or PBS for vehicle control was given once daily. Pre- and posttreatment (day 1 or 5) were commenced at 1 week before and 1 or 5 days after intravitreal injections, respectively, and were continued until postinjection day 28. Effects of treatment on retinal structure and functions were evaluated using optical coherence tomography (OCT), doppler OCT and electroretinogram measurements at baseline, post-injection days 10 and 28. RGC survival was evaluated by using RBPMS immunostaining on retinal wholemounts. RESULTS: ET-1 injection in vehicle control induced transient reductions in arterial flow and retinal functions, leading to significant RNFL thinning and RGC loss at day 28. Although ET-1 induced a transient loss in blood flow or retinal functions in all LbGP groups, LbGP treatments facilitated better restoration of retinal flow and retinal functions as compared with the vehicle control. Also, all three LbGP treatment groups (i.e. pre- and posttreatments from days 1 or 5) significantly preserved thRNFL thickness and RGC densities. No significant difference in protective effects was observed among the three LbGP treatment groups. CONCLUSION: LbGP demonstrated neuroprotective effects in a mouse model of ET-1 induced RGC degeneration, with treatment applied either as a pretreatment, immediate or delayed posttreatment. LbGP treatment promoted a better restoration of retinal blood flow, and protected the RNFL, RGC density and retinal functions. This study showed the translational potential of LB as complementary treatment for glaucoma management.


Assuntos
Endotelina-1 , Camundongos Endogâmicos C57BL , Neuroproteção , Células Ganglionares da Retina , Animais , Células Ganglionares da Retina/efeitos dos fármacos , Células Ganglionares da Retina/patologia , Células Ganglionares da Retina/metabolismo , Endotelina-1/metabolismo , Neuroproteção/efeitos dos fármacos , Eletrorretinografia , Lycium/química , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Degeneração Retiniana/tratamento farmacológico , Degeneração Retiniana/patologia , Tomografia de Coerência Óptica , Masculino , Camundongos , Degeneração Neural/patologia , Degeneração Neural/tratamento farmacológico
11.
J Cancer ; 15(15): 4902-4921, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39132155

RESUMO

Colorectal cancer (CRC) is a common malignant tumor and is one of the three most common cancers worldwide. Traditional surgical treatment, supplemented by chemotherapy and radiotherapy, has obvious side effects on patients. Immunotherapy may lead to some unpredictable complications. Low introduction rate and high cost are some of the problems of gene therapy, so finding a safe, reliable and least toxic treatment method became the main research direction for this study. Lactic acid bacteria and their metabolites are widely used in functional foods or as adjuvant therapies for various diseases because they are safe to eat and have no adverse reactions. Research has shown that lactic acid bacteria and their metabolites play an auxiliary therapeutic role in colorectal cancer mainly by improving the intestinal flora composition, inhibiting the growth of pathogenic bacteria and inhibiting the proliferation of cancer cells. It is now widely believed that the substances that probiotics such as lactic acid bacteria exert anti-cancer effects are mainly secondary metabolites such as butyric acid. Lb. plantarum AY01 isolated from fermented food has good anti-cancer ability, and its main anti-cancer substance is 2'-deoxyinosine. Through flow cytometry detection, it was found that Lb. plantarum AY01 can block cell proliferation in the S phase. In addition, Lb. plantarum AY01 culture reduces the sensitivity of mice to colitis-associated CRC induced by azoxymethane (AOM)/dextran sulfate sodium salt (DSS) and exhibits the occurrence and promotion of tumors. According to transcriptome analysis, Lb. plantarum AY01 may induce apoptosis of colorectal cancer cells by activating the p38 MAPK pathway. This experiment provided possibilities for the treatment of CRC.

12.
Cancer Sci ; 115(9): 2998-3012, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39013843

RESUMO

In our previous study, we found that small ubiquitin-related modifier (SUMO)-activating enzyme ubiquitin-associated-2 domain (UBA2) was upregulated in hepatocellular carcinoma (HCC) patients who were insensitive to chemoembolization. In this study, we aimed to investigate the role of UBA2 in HCC progression. Three cohorts were used to evaluate the efficacy of UBA2 as a prognostic factor for HCC. Our results indicated that UBA2 was associated with aggressive clinical behaviors and was a strong indicator of poor prognosis in HCC. In vitro experiments demonstrated that UBA2 accelerated cell growth, invasion, and migration. These results were further supported by in vivo experiments. RNA-sequencing analysis indicated NQO1 as a target of UBA2, with its levels altering following UBA2 manipulation. The results were verified by western blotting (WB) and quantitative PCR. The SUMOplot Analysis Program predicted lysine residue K240 as a modification target of UBA2, which was confirmed by immunoprecipitation (IP) assays. Subsequent mutation of NQO1 at K240 in HCC cell lines and functional assays revealed the significance of this modification. In addition, the oncogenic effect of UBA2 could be reversed by the SUMO inhibitor ML792 in vivo and in vitro. In conclusion, our study elucidated the regulatory mechanism of UBA2 in HCC and suggested that the SUMO inhibitor ML792 may be an effective combinatory treatment for patients with aberrant UBA2 expression.


Assuntos
Carcinoma Hepatocelular , Proliferação de Células , Neoplasias Hepáticas , NAD(P)H Desidrogenase (Quinona) , Enzimas Ativadoras de Ubiquitina , Humanos , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , NAD(P)H Desidrogenase (Quinona)/genética , NAD(P)H Desidrogenase (Quinona)/metabolismo , Masculino , Linhagem Celular Tumoral , Animais , Feminino , Enzimas Ativadoras de Ubiquitina/genética , Enzimas Ativadoras de Ubiquitina/metabolismo , Camundongos , Sistema de Sinalização das MAP Quinases , Pessoa de Meia-Idade , Prognóstico , Sumoilação , Movimento Celular/genética , Regulação Neoplásica da Expressão Gênica , Camundongos Nus
13.
Endosc Ultrasound ; 13(2): 89-93, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38947750

RESUMO

Background and Objectives: EUS-guided portal pressure gradient (PPG) is a novel technique that permits a true, direct measure of portal vein pressure and hepatic vein pressure. This article details our experience and lessons learned from 20 consecutive outpatient EUS-PPG procedures performed at a single center, along with simultaneous EUS-guided liver biopsy, variceal screening, and variceal banding. Methods: Data on the first 20 patients who underwent EUS-PPG at a single center were retrospectively viewed and analyzed. The effects of various liver diseases or other patient-related factors on the clinical and technical success of EUS-PPG measurements, as well as EUS-guided liver biopsy (EUS-LB), were evaluated. During the procedure, if esophageal varices were encountered, they were assessed, and if felt to be clinically indicated, endoscopic variceal ligation was performed. Results: The 20 patients included 10 male and 10 female patients. All procedures were technically successful. In all patients, the portal vein and hepatic veins could be easily identified. One adverse event of bleeding occurred during the EUS-PPG measuring procedure. All 20 EUS-LBs were technically successful and yielded adequate samples for histological evaluations, with an average of 25 complete portal tracts per sample. Among patients with esophageal varices, 40% of patients underwent banding. The mean EUS-PPG among 5 patients with esophageal varices was 11.6 mm Hg, compared with 3.2 mm Hg among 15 patients without esophageal varices. Conclusion: This study demonstrates that EUS-PPG is a novel, safe, reproducible, and effective technique. Also, the fact that EUS-PPG, EUS-LB, variceal screening, and variceal banding could be performed in 1 session and on an outpatient basis speaks to the growing relevance and impact of the nascent field of endohepatology.

14.
Comput Biol Chem ; 112: 108111, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38879954

RESUMO

Oxyresveratrol (OXY), a natural stilbenoid in mulberry fruits, is known for its diverse pharmacological properties. However, its clinical use is hindered by low water solubility and limited bioavailability. In the present study, the inclusion complexes of OXY with ß-cyclodextrin (ßCD) and its three analogs, dimethyl-ß-cyclodextrin (DMßCD), hydroxypropyl-ß-cyclodextrin (HPßCD) and sulfobutylether-ß-cyclodextrin (SBEßCD), were investigated using in silico and in vitro studies. Molecular docking revealed two binding orientations of OXY, namely, 4',6'-dihydroxyphenyl (A-form) and 5,7-benzenediol ring (B-form). Molecular Dynamics simulations suggested the formation of inclusion complexes with ßCDs through two distinct orientations, with OXY/SBEßCD exhibiting maximum atom contacts and the lowest solvent-exposed area in the hydrophobic cavity. These results corresponded well with the highest binding affinity observed in OXY/SBEßCD when assessed using the MM/GBSA method. Beyond traditional simulation methods, Ligand-binding Parallel Cascade Selection Molecular Dynamics method was employed to investigate how the drug enters and accommodates within the hydrophobic cavity. The in silico results aligned with stability constants: SBEßCD (2060 M-1), HPßCD (1860 M-1), DMßCD (1700 M-1), and ßCD (1420 M-1). All complexes exhibited a 1:1 binding mode (AL type), with SBEßCD enhancing OXY solubility (25-fold). SEM micrographs, DSC thermograms, FT-IR and 1H NMR spectra confirm the inclusion complex formation, revealing novel surface morphologies, distinctive thermal behaviors, and new peaks. Notably, the inhibitory impact on the proliferation of breast cancer cell lines, MCF-7, exhibited by inclusion complexes particularly OXY/DMßCD, OXY/HPßCD, and OXY/SBEßCD were markedly superior compared to that of OXY alone.


Assuntos
Simulação de Acoplamento Molecular , Solubilidade , Estilbenos , beta-Ciclodextrinas , beta-Ciclodextrinas/química , Estilbenos/química , Humanos , Simulação de Dinâmica Molecular , Proliferação de Células/efeitos dos fármacos , Estrutura Molecular , Extratos Vegetais/química , Ensaios de Seleção de Medicamentos Antitumorais , Estabilidade de Medicamentos
15.
Bioorg Med Chem Lett ; 110: 129852, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38925524

RESUMO

The global outbreak of the COVID-19 pandemic caused by the SARS-CoV-2 virus had led to profound respiratory health implications. This study focused on designing organoselenium-based inhibitors targeting the SARS-CoV-2 main protease (Mpro). The ligand-binding pathway sampling method based on parallel cascade selection molecular dynamics (LB-PaCS-MD) simulations was employed to elucidate plausible paths and conformations of ebselen, a synthetic organoselenium drug, within the Mpro catalytic site. Ebselen effectively engaged the active site, adopting proximity to H41 and interacting through the benzoisoselenazole ring in a π-π T-shaped arrangement, with an additional π-sulfur interaction with C145. In addition, the ligand-based drug design using the QSAR with GFA-MLR, RF, and ANN models were employed for biological activity prediction. The QSAR-ANN model showed robust statistical performance, with an r2training exceeding 0.98 and an RMSEtest of 0.21, indicating its suitability for predicting biological activities. Integration the ANN model with the LB-PaCS-MD insights enabled the rational design of novel compounds anchored in the ebselen core structure, identifying promising candidates with favorable predicted IC50 values. The designed compounds exhibited suitable drug-like characteristics and adopted an active conformation similar to ebselen, inhibiting Mpro function. These findings represent a synergistic approach merging ligand and structure-based drug design; with the potential to guide experimental synthesis and enzyme assay testing.


Assuntos
Antivirais , Proteases 3C de Coronavírus , Desenho de Fármacos , Isoindóis , Aprendizado de Máquina , Simulação de Dinâmica Molecular , Compostos Organosselênicos , Inibidores de Proteases , Relação Quantitativa Estrutura-Atividade , SARS-CoV-2 , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/enzimologia , Compostos Organosselênicos/química , Compostos Organosselênicos/farmacologia , Compostos Organosselênicos/síntese química , Isoindóis/química , Isoindóis/farmacologia , Isoindóis/síntese química , Proteases 3C de Coronavírus/antagonistas & inibidores , Proteases 3C de Coronavírus/metabolismo , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Inibidores de Proteases/síntese química , Antivirais/farmacologia , Antivirais/química , Antivirais/síntese química , Humanos , Azóis/química , Azóis/farmacologia , Azóis/síntese química , COVID-19/virologia , Domínio Catalítico
16.
Materials (Basel) ; 17(12)2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38930313

RESUMO

This study investigates the potential benefits of integrating coarser particle size distributions (PSDs) of 45-106 µm into laser-based powder bed fusion of metals (PBF-LB/M), aiming to reduce costs while maintaining quality standards. Despite the considerable advantages of PBF-LB/M for producing intricate geometries with high precision, the high cost of metal powders remains a barrier to its widespread adoption. By exploring the use of coarser PSDs, particularly from electron beam-based powder bed fusion of metals (PBF-EB/M), significant cost-saving opportunities are identified. Through a comprehensive powder characterization, process analysis, and mechanical property evaluation, this study demonstrates that PBF-LB/M can effectively utilize coarser powders while achieving comparable mechanical properties as those produced with a 20-53 µm PSD. Adaptations to the process parameters enable the successful processing of coarser powders, maintaining high relative density components with minimal porosity. Additionally, market surveys reveal substantial cost differentials between PBF-LB/M and PBF-EB/M powders, indicating a 40% cost reduction potential for the feedstock material by integrating coarser PSDs into PBF-LB/M. Overall, this study provides valuable insights into the economic and technical feasibility of printing with coarser powders in PBF-LB/M, offering promising avenues for cost reduction without compromising quality, thus enhancing competitiveness and the adoption of the technology in manufacturing applications.

17.
Cancers (Basel) ; 16(12)2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38927905

RESUMO

Effective cancer therapy with limited adverse effects is a major challenge in the medical field. This is especially complicated by the development of acquired chemoresistance. Understanding the mechanisms that underlie these processes remains a major effort in cancer research. In this review, we focus on the dual role that Bid protein plays in apoptotic cell death via the mitochondrial pathway, in oncogenesis and in cancer therapeutics. The BH3 domain in Bid and the anti-apoptotic mitochondrial proteins (Bcl-2, Bcl-XL, mitochondrial ATR) it associates with at the outer mitochondrial membrane provides us with a viable target in cancer therapy. We will discuss the roles of Bid, mitochondrial ATR, and other anti-apoptotic proteins in intrinsic apoptosis, exploring how their interaction sustains cellular viability despite the initiation of upstream death signals. The unexpected upregulation of this Bid protein in cancer cells can also be instrumental in explaining the mechanisms behind acquired chemoresistance. The stable protein associations at the mitochondria between tBid and anti-apoptotic mitochondrial ATR play a crucial role in maintaining the viability of cancer cells, suggesting a novel mechanism to induce cancer cell apoptosis by freeing tBid from the ATR associations at mitochondria.

18.
Appl Microbiol Biotechnol ; 108(1): 361, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38837050

RESUMO

Lactobacillus delbrueckii subsp. bulgaricus and Lactiplantibacillus plantarum are two lactic acid bacteria (LAB) widely used in the food industry. The objective of this work was to assess the resistance of these bacteria to freeze- and spray-drying and study the mechanisms involved in their loss of activity. The culturability and acidifying activity were measured to determine the specific acidifying activity, while membrane integrity was studied by flow cytometry. The glass transitions temperature and the water activity of the dried bacterial suspensions were also determined. Fourier transform infrared (FTIR) micro-spectroscopy was used to study the biochemical composition of cells in an aqueous environment. All experiments were performed after freezing, drying and storage at 4, 23 and 37 °C. The results showed that Lb. bulgaricus CFL1 was sensitive to osmotic, mechanical, and thermal stresses, while Lpb. plantarum WCFS1 tolerated better the first two types of stress but was more sensitive to thermal stress. Moreover, FTIR results suggested that the sensitivity of Lb. bulgaricus CFL1 to freeze-drying could be attributed to membrane and cell wall degradation, whereas changes in nucleic acids and proteins would be responsible of heat inactivation of both strains associated with spray-drying. According to the activation energy values (47-85 kJ/mol), the functionality loss during storage is a chemically limited reaction. Still, the physical properties of the glassy matrix played a fundamental role in the rates of loss of activity and showed that a glass transition temperature 40 °C above the storage temperature is needed to reach good preservation during storage. KEY POINTS: • Specific FTIR bands are proposed as markers of osmotic, mechanic and thermal stress • Lb. bulgaricus CFL1 was sensitive to all three stresses, Lpb. plantarum WCFS1 to thermal stress only • Activation energy revealed chemically limited reactions ruled the activity loss in storage.


Assuntos
Liofilização , Liofilização/métodos , Espectroscopia de Infravermelho com Transformada de Fourier , Secagem por Atomização , Viabilidade Microbiana , Lactobacillus plantarum/metabolismo , Lactobacillus plantarum/fisiologia , Lactobacillus delbrueckii/metabolismo , Lactobacillus delbrueckii/fisiologia , Lactobacillales/metabolismo , Lactobacillales/fisiologia , Dessecação
19.
Eur J Pharmacol ; 977: 176703, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38839028

RESUMO

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by multi-organ involvement and autoantibody production. Patients with SLE face a substantial risk of developing lupus nephritis (LN), which imposes a substantial burden on both patients and their families. Protein phosphatase 2A (PP2A) is a widely distributed serine/threonine phosphatase that participates in regulating multiple signaling pathways. Inhibition of PP2A has been implicated in the treatment of various diseases. LB-100, a small molecule inhibitor of PP2A, has demonstrated anti-tumor therapeutic effects and high safety profile in preclinical experiments. However, the role of PP2A and its inhibitor has been insufficiently studied in LN. In this study, we assessed the potential effects of LB-100 in both MRL/lpr mice and R848-induced BALB/c mice. Our findings indicated that LB-100 administration led to reduced spleen enlargement, decreased deposition of immune complexes, ameliorated renal damage, and improved kidney function in both spontaneous and R848-induced lupus mouse models. Importantly, we observed the formation of tertiary lymphoid structures (TLSs) in the kidneys of two distinct lupus mouse models. The levels of signature genes of TLS were elevated in the kidneys of lupus mice, whereas LB-100 mitigated chemokine production and inhibited TLS formation. In addition, we confirmed that inhibition or knockdown of PP2A reduced the production of T cell-related chemokines by renal tubular epithelial cells (RTEC). In summary, our study highlighted the renal protective potential of the PP2A inhibitor LB-100 in two distinct lupus mouse models, suggesting its potential as a novel strategy for treating LN and other autoimmune diseases.


Assuntos
Nefrite Lúpica , Camundongos Endogâmicos BALB C , Proteína Fosfatase 2 , Estruturas Linfoides Terciárias , Animais , Proteína Fosfatase 2/antagonistas & inibidores , Proteína Fosfatase 2/metabolismo , Nefrite Lúpica/tratamento farmacológico , Nefrite Lúpica/patologia , Camundongos , Estruturas Linfoides Terciárias/patologia , Feminino , Camundongos Endogâmicos MRL lpr , Rim/efeitos dos fármacos , Rim/patologia , Rim/metabolismo , Modelos Animais de Doenças , Baço/efeitos dos fármacos , Baço/patologia , Baço/imunologia , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Piperazinas
20.
bioRxiv ; 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38746341

RESUMO

Extracellular vesicles (EVs) are particles secreted by all cells that carry bioactive cargo and facilitate intercellular communication with roles in normal physiology and disease pathogenesis. EVs have tremendous diagnostic and therapeutic potential and accordingly, the EV field has grown exponentially in recent years. Bulk assays lack the sensitivity to detect rare EV subsets relevant to disease, and while single EV analysis techniques remedy this, they are undermined by complicated detection schemes often coupled with prohibitive instrumentation. To address these issues, we propose a microfluidic technique for EV characterization called 'catch and display for liquid biopsy (CAD-LB)'. CAD-LB rapidly captures fluorescently labeled EVs in the similarly-sized pores of an ultrathin silicon nitride membrane. Minimally processed sample is introduced via pipette injection into a simple microfluidic device which is directly imaged using fluorescence microscopy for a rapid assessment of EV number and biomarker colocalization. In this work, nanoparticles were first used to define the accuracy and dynamic range for counting and colocalization by CAD-LB. Following this, the same assessments were made for purified EVs and for unpurified EVs in plasma. Biomarker detection was validated using CD9 in which Western blot analysis confirmed that CAD-LB faithfully recapitulated differing expression levels among samples. We further verified that CAD-LB captured the known increase in EV-associated ICAM-1 following the cytokine stimulation of endothelial cells. Finally, to demonstrate CAD-LB's clinical potential, we show that EV biomarkers indicative of immunotherapy responsiveness are successfully detected in the plasma of bladder cancer patients undergoing immune checkpoint blockade.

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