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1.
Cell ; 146(3): 471-84, 2011 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-21816279

RESUMEN

Clathrin-mediated endocytosis (CME) regulates many cell physiological processes such as the internalization of growth factors and receptors, entry of pathogens, and synaptic transmission. Within the endocytic network, clathrin functions as a central organizing platform for coated pit assembly and dissociation via its terminal domain (TD). We report the design and synthesis of two compounds named pitstops that selectively block endocytic ligand association with the clathrin TD as confirmed by X-ray crystallography. Pitstop-induced inhibition of clathrin TD function acutely interferes with receptor-mediated endocytosis, entry of HIV, and synaptic vesicle recycling. Endocytosis inhibition is caused by a dramatic increase in the lifetimes of clathrin coat components, including FCHo, clathrin, and dynamin, suggesting that the clathrin TD regulates coated pit dynamics. Pitstops provide new tools to address clathrin function in cell physiology with potential applications as inhibitors of virus and pathogen entry and as modulators of cell signaling.


Asunto(s)
Clatrina/química , Clatrina/metabolismo , Invaginaciones Cubiertas de la Membrana Celular/metabolismo , Técnicas Citológicas/métodos , Bibliotecas de Moléculas Pequeñas , Complejo 2 de Proteína Adaptadora/metabolismo , Animales , Células Cultivadas , Invaginaciones Cubiertas de la Membrana Celular/efectos de los fármacos , Cristalografía por Rayos X , Dinaminas/metabolismo , Endocitosis , Humanos , Ratones , Estructura Terciaria de Proteína , Transducción de Señal , Sinapsis/metabolismo , Sinapsis/ultraestructura
2.
Plant Dis ; 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38386305

RESUMEN

Mulberry (Morus alba L.) is highly important crop in Vietnam, playing a key role in the country's economy through sericulture, food supply, pharmaceuticals, and beverage industries (Nguyen et al., 2018; Rohela et al., 2020). Recently, many mulberry-growing areas in Lam Dong, Vietnam have reported severe symptoms associated with nematode infection, including yellowing leaves, stunted growth, and severe root galling, leading to a significant decline in mulberry productivity. From April to December 2022, twenty soil and root samples from mulberry-growing areas in Lam Dong (Da Teh: 11°28'48.11"N; 107°28'23.74"E elevation: 133m; Lam Ha 11°48'25.13"N; 108°14'7.13"E elevation: 848m) were collected to uncover the presence of Meloidogyne enterolobii parasitizing mulberry in Vietnam. One nematode population was randomly selected for characterizing in this study among analyzed nematode populations. Females were extracted from heavily galled roots (Fig. S1) from a single mulberry tree in Lam Dong, Vietnam, using a needle and forceps (Subbotin et al., 2021). The perineal patterns of adult females (n = 10) have an oval shape, with clearly visible phasmids, along with a prominently high and squared dorsal arch. The striae are smooth and coarse, while the perivulval region remains devoid of striae. The lateral lines appear indistinct, and the tail tip is easily observable. Morphometric measurements were as follows: body length = 585 ± 78 (464-724) µm, body width = 367 ± 75 (271-529) µm, neck length = 221.5 ± 30.7 (167-269.6) µm, stylet length = 13.1 ± 1.2 (11.4-15.1) µm, vulva-slit length 16.3±2.3 (10.4-18) µm, vulva-anus distance = 16.8±3.0 (11.4-18) µm, anus-tail tip distance = 10.3±2.1 (6.9-14.2) µm, interphasmidial distance = 15.9 ± 3.7 (10.3-23.4) µm. The morphology of this nematode population is highly in agreement with the original description of M. enterolobii (Yang & Eisenback, 1983). This population was also identified using the D2-D3 of 28S rRNA and 18S rRNA (Powers et al., 2017; Subbotin et al., 2006) regions. The D2-D3 of 28S rRNA sequences from this study (accession numbers: OR889633) exhibited 99.5-99.8% similarity to the sequences of M. enterolobii from GenBank (accession numbers: OR214950 and ON496981). While the 18S rRNA sequences (accession numbers: OR896547) showed 99.2-99.3% similarity to the sequences of M. enterolobii from GenBank (accession numbers: MZ955995, MZ531901, and MW488150). To carry out Koch's postulates, 2000 J2s from collected M. enterolobii egg masses (initial population) were inoculated on two-month-old plantlets of mulberry (n = 6), planted on 2L pots within a screenhouse, non-inoculated plantlets (n=6) served as negative controls. After 90 days post-inoculation, nematode reproduction factors (RF = final density (nematodes were extracted from the whole root system and corresponding soil samples (Subbotin et al., 2021)) / initial population) and root damage symptoms were evaluated. The inoculated plantlets exhibited consistent yellowing leaves, stunting, and root galling symptoms (Fig. S1), mirroring observations from the field, with an average RF of 11.5. Control plants displayed no symptoms. Root-knot nematodes extracted from the roots were identified as M. enterolobii through molecular analyses of D2-D3 of 28S and 18S rRNA regions (GenBank accession numbers: OR889634 (D2-D3 of 28S) and OR896548 (18S)), thereby confirming that mulberry acts as a host for M. enterolobii. Currently, this nematode has been reported to be associated with two different host plants, including guava (Trinh et al., 2022) and pomelo (Le et al., 2023). Our discovery marks the first documented case of Meloidogyne enterolobii parasitizing mulberry in Vietnam. While the impact on mulberry productivity remains to be really important for sericulture food supply, pharmaceuticals, and beverage industries; the aggressive nature of M. enterolobii, as observed in the field and confirmed by the screenhouse tests, raises concerns about potential economic losses in mulberry production. Therefore, further investigations are needed to assess the extent of M. enterolobii infestation in mulberry orchards and to develop effective control measures to safeguard the sustainability of mulberry cultivation in Vietnam.

3.
Small ; 19(18): e2208227, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36732906

RESUMEN

Peritumoral brain invasion is the main target to cure glioblastoma. Chemoradiotherapy and targeted therapies fail to combat peritumoral relapse. Brain inaccessibility and tumor heterogeneity explain this failure, combined with overlooking the peritumor microenvironment. Reduce graphene oxide (rGO) provides a unique opportunity to modulate the local brain microenvironment. Multimodal graphene impacts are reported on glioblastoma cells in vitro but fail when translated in vivo because of low diffusion. This issue is solved by developing a new rGO formulation involving ultramixing during the functionalization with polyethyleneimine (PEI) leading to the formation of highly water-stable rGO-PEI. Wide mice brain diffusion and biocompatibility are demonstrated. Using an invasive GL261 model, an anti-invasive effect is observed. A major unexpected modification of the peritumoral area is also observed with the neutralization of gliosis. In vitro, mechanistic investigations are performed using primary astrocytes and cytokine array. The result suggests that direct contact of rGO-PEIUT neutralizes astrogliosis, decreasing several proinflammatory cytokines that would explain a bystander tumor anti-invasive effect. rGO also significantly downregulates several proinvasive/protumoral cytokines at the tumor cell level. The results open the way to a new microenvironment anti-invasive nanotherapy using a new graphene nanomaterial that is optimized for in vivo brain delivery.


Asunto(s)
Glioblastoma , Grafito , Animales , Ratones , Glioblastoma/terapia , Citocinas , Encéfalo , Microambiente Tumoral
4.
BMC Public Health ; 23(1): 445, 2023 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-36882752

RESUMEN

BACKGROUND: University students are vulnerable to changes due to COVID-19 pandemic. Although warning has been made about the impact of this crisis on students' mental health, there are barely any sufficient study. This work investigated how the pandemic affected the mental health of students at the Vietnam National University of Ho Chi Minh City (VNU-HCMC) and efficiency of available mental health supportive methods. METHODS: An online survey was conducted among students at Vietnam National University of Ho Chi Minh City (VNU-HCMC) from October 18, 2021, to October 25, 2021. Microsoft Excel 16.51 (Microsoft, USA) and R language, Epi packages 2.44 and 4.1.1 (rdrr.io) were used for data analysis. RESULTS: Thirty-seven thousand one hundred fifty students participated in the survey, including 48.4% female and 51.6% male. Online learning pressure was mainly recorded (65.1%). Many students suffered from sleeping disorders (56.2%). Some reported being victims of abuse (5.9%). Female students expressed a significantly higher level of distress than males, particularly the feeling of ambiguity about the purpose of life (p-value < 0.0001, OR: 0.94, 95% CI: [0.95-0.98]). Third-year students suffered higher stress levels than others, especially in online learning (68.8%, p-value < 0.05). Mental health statuses among students of different lockdown status regions were not significantly different. Therefore, lockdown status did not affect the stress levels of students which suggested that poor mental health outcomes seemed to root in the suspension of everyday university life rather than the prohibition of going out. CONCLUSIONS: During COVID-19, students experienced lots of stress and mental problems. These findings underscore the importance of academic and innovative activities, bringing attention to the needs of interactive study and extra-curricular activities.


Asunto(s)
COVID-19 , Salud Mental , Estudiantes , Femenino , Humanos , Masculino , Control de Enfermedades Transmisibles , COVID-19/epidemiología , Estudios Transversales , Pandemias , Pueblos del Sudeste Asiático , Vietnam/epidemiología , Estudiantes/psicología
5.
Molecules ; 28(17)2023 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-37687204

RESUMEN

Chemical profiling for quality monitoring and evaluation of medicinal plants is gaining attention. This study aims to develop an HPLC method followed by multivariate analysis to obtain HPLC profiles of five specific flavonoids, including rutin (1), hyperin (2), isoquercitrin (3), quercitrin (4), and quercetin (5) from Houttuynia cordata leaves and powder products and assess the quality of H. cordata samples. Eventually, we successfully established HPLC-based flavonoid profiles and quantified the contents of 32 H. cordata fresh leave samples and four powder products. The study also quantified the contents of those five essential flavonoids using an optimized RP-HPLC method. Peak areas of samples were then investigated with principal component analysis (PCA) and hierarchical cluster analysis (HCA) to evaluate the similarity and variance. Principal components in PCA strongly influenced by hyperin and quercetin showed that the samples were clustered into subgroups, demonstrating H. cordata samples' quality. The results of HCA showed the similarity and divided the samples into seven subgroups. In conclusion, we have successfully developed a practical methodology that combined the HPLC-based flavonoid profiling and multivariate analysis for the quantification and quality control of H. cordata samples from fresh leaves and powder products. For further studies, we will consider various environmental factors, including climate and soil factors, to investigate their effects on the flavonoid contents of H. cordata.


Asunto(s)
Flavonoides , Houttuynia , Quercetina , Cromatografía Líquida de Alta Presión , Polvos , Hojas de la Planta
6.
Sensors (Basel) ; 22(21)2022 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-36365907

RESUMEN

An XYZ compliant micropositioner has been widely mentioned in precision engineering, but the displacements in the X, Y, and Z directions are often not the same. In this study, a design and optimization for a new XYZ micropositioner are developed to obtain three same displacements in three axes. The proposed micropositioner is a planar mechanism whose advantage is a generation of three motions with only two actuators. In the design strategy, the proposed micropositioner is designed by a combination of a symmetrical four-lever displacement amplifier, a symmetrical parallel guiding mechanism, and a symmetrical parallel redirection mechanism. The Z-shaped hinges are used to gain motion in the Z-axis displacement. Four flexure right-circular hinges are combined with two rigid joints and two flexure leaf hinges to permit two large X-and-Y displacements. The symmetrical four-lever displacement amplifier is designed to increase the micropositioner's travel. The displacement sensor is built by embedding the strain gauges on the hinges of the micropositioner, which is developed to measure the travel of the micropositioner. The behaviors and performances of the micropositioner are modeled by using the Taguchi-based response surface methodology. Additionally, the geometrical factors of the XYZ micropositioner are optimized by teaching-learning-based optimization. The optimized design parameters are defined with an A of 0.9 mm, a B of 0.8 mm, a C of 0.57 mm, and a D of 0.7 mm. The safety factor gains 1.85, while the displacement achieves 515.7278 µm. The developed micropositioner is a potential option for biomedical sample testing in a nanoindentation system.


Asunto(s)
Materiales Biocompatibles , Movimiento (Física)
7.
Traffic ; 16(6): 635-54, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25693808

RESUMEN

Chlorpromazine is a phenothiazine-derived antipsychotic drug (APD) that inhibits clathrin-mediated endocytosis (CME) in cells by an unknown mechanism. We examined whether its action and that of other APDs might be mediated by the GTPase activity of dynamin. Eight of eight phenothiazine-derived APDs inhibited dynamin I (dynI) in the 2-12 µm range, the most potent being trifluoperazine (IC50 2.6 ± 0.7 µm). They also inhibited dynamin II (dynII) at similar concentrations. Typical and atypical APDs not based on the phenothiazine scaffold were 8- to 10-fold less potent (haloperidol and clozapine) or were inactive (droperidol, olanzapine and risperidone). Kinetic analysis showed that phenothiazine-derived APDs were lipid competitive, while haloperidol was uncompetitive with lipid. Accordingly, phenothiazine-derived APDs inhibited dynI GTPase activity stimulated by lipids but not by various SH3 domains. All dynamin-active APDs also inhibited transferrin (Tfn) CME in cells at related potencies. Structure-activity relationships (SAR) revealed dynamin inhibition to be conferred by a substituent group containing a terminal tertiary amino group at the N2 position. Chlorpromazine was previously proposed to target AP-2 recruitment in the formation of clathrin-coated vesicles (CCV). However, neither chlorpromazine nor thioridazine affected AP-2 interaction with amphiphysin or clathrin. Super-resolution microscopy revealed that chlorpromazine blocks neither clathrin recruitment by AP-2, nor AP-2 recruitment, showing that CME inhibition occurs downstream of CCV formation. Overall, potent dynamin inhibition is a shared characteristic of phenothiazine-derived APDs, but not other typical or atypical APDs, and the data indicate that dynamin is their likely in-cell target in endocytosis.


Asunto(s)
Antipsicóticos/farmacología , Clatrina/metabolismo , Dinaminas/metabolismo , Endocitosis/efectos de los fármacos , Fenotiazinas/farmacología , Línea Celular Tumoral , Vesículas Cubiertas por Clatrina/metabolismo , Humanos , Transferrina/metabolismo
8.
Org Biomol Chem ; 14(47): 11266-11278, 2016 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-27853797

RESUMEN

The development of a (Z)-5-((6,8-dichloro-4-oxo-4H-chromen-3-yl)methylene)-2-thioxothiazolidin-4-one (2), rhodanine-based lead that led to the Pitstop® 2 family of clathrin inhibitors is described herein. Head group substitution and bioisosteric replacement of the rhodanine core with a 2-aminothiazol-4(5H)-one scaffold eliminated off target dynamin activity. A series of N-substituents gave first phenylglycine (20, IC50 ∼ 20 µM) then phenyl (25, IC50 ∼ 7.1 µM) and 1-napthyl sulfonamide (26, Pitstop® 2 compound, IC50 ∼ 1.9 µM) analogues with good activity, validating this approach. A final library exploring the head group resulted in three analogues displaying either slight improvements or comparable activity (33, 38, and 29 with IC50 ∼ 1.4, 1.6 and 1.8 µM respectively) and nine others with IC50 < 10 µM. These results were rationalized using in silico docking studies. Docking studies predicted enhanced Pitstop® 2 family binding, not a loss of binding, within the Pistop® groove of the reported clathrin mutant invalidating recent assumptions of poor selectivity for this family of clathrin inhibitors.


Asunto(s)
Clatrina/antagonistas & inhibidores , Sulfonamidas/química , Sulfonamidas/farmacología , Clatrina/química , Clatrina/metabolismo , Diseño de Fármacos , Concentración 50 Inhibidora , Simulación del Acoplamiento Molecular , Conformación Proteica , Relación Estructura-Actividad , Sulfonamidas/metabolismo
9.
Macromol Rapid Commun ; 37(6): 539-44, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26787365

RESUMEN

Cobalt-mediated radical polymerization (CMRP) of vinyl acetate (VAc) is successfully achieved in supercritical carbon dioxide (scCO2). CMRP of VAc is conducted using an alkyl-cobalt(III) adduct that is soluble in scCO2. Kinetics studies coupled to visual observations of the polymerization medium highlight that the melt viscosity and PVAc molar mass (Mn) are key parameters that affect the CMRP in scCO2. It is noticed that CMRP is controlled for Mn up to 10 000 g mol(-1), but loss of control is progressively observed for higher molar masses when PVAc precipitates in the polymerization medium. Low molar mass PVAc macroinitiator, prepared by CMRP in scCO2, is then successfully used to initiate the acrylonitrile polymerization. PVAc-b-PAN block copolymer is collected as a free flowing powder at the end of the process although the dispersity of the copolymer increases with the reaction time. Although optimization is required to decrease the dispersity of the polymer formed, this CMRP process opens new perspectives for macromolecular engineering in scCO2 without the utilization of fluorinated comonomers or organic solvents.


Asunto(s)
Acrilonitrilo/química , Dióxido de Carbono/química , Cobalto/química , Compuestos de Vinilo/química , Catálisis , Cinética , Peso Molecular , Polimerizacion
10.
Traffic ; 14(12): 1272-89, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24025110

RESUMEN

Dynamin GTPase activity increases when it oligomerizes either into helices in the presence of lipid templates or into rings in the presence of SH3 domain proteins. Dynasore is a dynamin inhibitor of moderate potency (IC50 ~ 15 µM in vitro). We show that dynasore binds stoichiometrically to detergents used for in vitro drug screening, drastically reducing its potency (IC50 = 479 µM) and research tool utility. We synthesized a focused set of dihydroxyl and trihydroxyl dynasore analogs called the Dyngo™ compounds, five of which had improved potency, reduced detergent binding and reduced cytotoxicity, conferred by changes in the position and/or number of hydroxyl substituents. The Dyngo compound 4a was the most potent compound, exhibiting a 37-fold improvement in potency over dynasore for liposome-stimulated helical dynamin activity. In contrast, while dynasore about equally inhibited dynamin assembled in its helical or ring states, 4a and 6a exhibited >36-fold reduced activity against rings, suggesting that they can discriminate between helical or ring oligomerization states. 4a and 6a inhibited dynamin-dependent endocytosis of transferrin in multiple cell types (IC50 of 5.7 and 5.8 µM, respectively), at least sixfold more potently than dynasore, but had no effect on dynamin-independent endocytosis of cholera toxin. 4a also reduced synaptic vesicle endocytosis and activity-dependent bulk endocytosis in cultured neurons and synaptosomes. Overall, 4a and 6a are improved and versatile helical dynamin and endocytosis inhibitors in terms of potency, non-specific binding and cytotoxicity. The data further suggest that the ring oligomerization state of dynamin is not required for clathrin-mediated endocytosis.


Asunto(s)
Dinaminas/antagonistas & inhibidores , Endocitosis/efectos de los fármacos , Hidrazonas/farmacología , Naftoles/farmacología , Animales , Línea Celular Tumoral , Células Cultivadas , Toxina del Cólera/metabolismo , Relación Dosis-Respuesta a Droga , Descubrimiento de Drogas , Dinaminas/metabolismo , Ensayos Analíticos de Alto Rendimiento , Humanos , Hidrazonas/síntesis química , Hidrazonas/química , Naftoles/química , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Unión Proteica , Transporte de Proteínas , Ratas , Ratas Sprague-Dawley , Ovinos , Vesículas Sinápticas/efectos de los fármacos , Vesículas Sinápticas/metabolismo , Transferrinas/metabolismo
11.
Biochem Biophys Res Commun ; 468(3): 454-62, 2015 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-26129773

RESUMEN

Nanosized materials and multifunctional nanoscale platforms have attracted in the last years considerable interest in a variety of different fields including biomedicine. Carbon nanotubes and graphene are some of the most widely used carbon nanomaterials (CNMs) due to their unique morphology and structure and their characteristic physicochemical properties. Their high surface area allows efficient drug loading and bioconjugation and makes them the ideal platforms for decoration with magnetic nanoparticles (MNPs). In the biomedical area, MNPs are of particular importance due to their broad range of potential applications in drug delivery, non-invasive tumor imaging and early detection based on their optical and magnetic properties. The remarkable characteristics of CNMs and MNPs can be combined leading to CNM/MNP hybrids which offer numerous promising, desirable and strikingly advantageous properties for improved performance in comparison to the use of either material alone. In this minireview, we attempt to comprehensively report the most recent advances made with CNMs conjugated to different types of MNPs for magnetic targeting, magnetic manipulation, capture and separation of cells towards development of magnetic carbon-based devices.


Asunto(s)
Separación Celular/métodos , Preparaciones de Acción Retardada/química , Nanopartículas de Magnetita/química , Micromanipulación/métodos , Nanoconjugados/química , Nanotubos de Carbono/química , Preparaciones de Acción Retardada/efectos de la radiación , Nanopartículas de Magnetita/efectos de la radiación , Nanoconjugados/efectos de la radiación , Nanotubos de Carbono/efectos de la radiación
12.
Org Biomol Chem ; 13(29): 8016-28, 2015 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-26118967

RESUMEN

Fragment-based in silico screening against dynamin I (dynI) GTPase activity identified the 1,8-naphthalimide framework as a potential scaffold for the design of new inhibitors targeting the GTP binding pocket of dynI. Structure-based design, synthesis and subsequent optimization resulted in the development of a library of 1,8-naphthalimide derivatives, called the Naphthaladyn™ series, with compounds 23 and 29 being the most active (IC50 of 19.1 ± 0.3 and 18.5 ± 1.7 µM respectively). Compound 29 showed effective inhibition of clathrin-mediated endocytosis (IC50(CME) 66 µM). The results introduce 29 as an optimised GTP-competitive lead Naphthaladyn™ compound for the further development of naphthalimide-based dynI GTPase inhibitors.


Asunto(s)
Dinamina I/antagonistas & inhibidores , Naftalimidas/farmacología , Aminas/química , Sitios de Unión , Línea Celular Tumoral , Clatrina/metabolismo , Dinamina I/metabolismo , Endocitosis/efectos de los fármacos , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Guanosina Trifosfato/metabolismo , Humanos , Modelos Moleculares , Naftalimidas/química , Fosfatidilserinas/farmacología , Estructura Secundaria de Proteína
13.
J Asian Nat Prod Res ; 17(10): 1010-7, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26001122

RESUMEN

Using combined chromatographic methods, two asterosaponins (compounds 1 and 2), including a new compound novaeguinoside E (compound 1), and six glycosylated polyhydroxysteroids (compounds 3-8) were isolated from a methanol extract of the starfish Culcita novaeguineae. Their structures were determined on the basis of spectroscopic data ((1)H and (13)C NMR, HSQC, HMBC, (1)H-(1)H COSY, ROESY, and HRESI-MS) and by comparison with the literature values. The new compound 1 represents the third example of asterosaponins containing the 5α-cholesta-9(1l)-en-3ß,6α,20,22-tetraol aglycone. Among isolated compounds, 4-7 exhibited moderate to weak cytotoxic activities against five human cancer cell lines such as Hep-G2 (hepatoma), KB (epidermoid carcinoma), LNCaP (prostate cancer), MCF7 (breast cancer), and SK-Mel2 (melanoma).


Asunto(s)
Antineoplásicos/aislamiento & purificación , Antineoplásicos/farmacología , Saponinas/aislamiento & purificación , Saponinas/farmacología , Estrellas de Mar/química , Esteroides/aislamiento & purificación , Esteroides/farmacología , Animales , Antineoplásicos/química , Ensayos de Selección de Medicamentos Antitumorales , Glicosilación , Células Hep G2 , Humanos , Células KB , Masculino , Melanoma , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Saponinas/química , Esteroides/química
14.
Bioresour Technol ; 394: 130187, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38096999

RESUMEN

The discovery of formate dehydrogenase (Me-FDH1) from Methylorubrum extorquens has provided an avenue for sustainable CO2 fixation and utilization. However, the mass production of Me-FDH1 is challenging due to the presence of its unique tungsto-bis-metalopterin guanine dinucleotide (W-bis-MGD) cofactor, limiting its practical applications. In this study, C. necator H16 is proposed as a host for the large-scale production of Me-FDH1, utilizing fructose as a carbon source and its inherent machinery for cofactor synthesis. In a minimal salt medium, C. necator H16 could produce active Me-FDH1, which exhibited a specific activity of 80 to 100 U/mg for CO2 conversion to formate. In fed batch bioreactor experiments, approximately 50 g CDW/L (cell dry weight/L) and 10,000 U/L Me-FDH1 were achieved within 50 h. This study highlights C. necator H16 as the recombinant host for Me-FDH1, paving the way for the future development of efficient mass-production methods for this crucial enzyme.


Asunto(s)
Cupriavidus necator , Formiato Deshidrogenasas , Dióxido de Carbono
15.
ChemMedChem ; : e202400253, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38894585

RESUMEN

Twenty-five chimera compounds of Pitstop® 1 and 2 were synthesised and screened for their ability to block the clathrin terminal domain-amphiphysin protein-protein interaction (NTD-PPI using an ELISA) and clathrin mediated endocytosis (CME) in cells.  Library 1 was based on Pitstop 2, but no notable clathrin PPI or in-cell activity was observed.  With the Pitstop 1, 16 analogues were produced with 1,8-naphthalic imide core as a foundation.  Analogues with methylene spaced linkers and simple amides showed a modest to good range of PPI inhibition (7.6 to 42.5 mM, naphthyl 39 and 4-nitrophenyl 40 respectively) activity.  These data reveal the importance of the naphthalene sulfonate moiety, with no des-SO3 analogue displaying PPI inhibition.  This was consistent with the observed analogue docked poses within the clathrin terminal domain Site 1 binding pocket.  Further modifications targeted the naphthalene imide moiety, with the installation of 5-Br (45a), 5-OH (45c) and 5-propyl ether (45d) moieties.  Among them, the OH 45c and propyl ether 45d retained PPI inhibition, with propyl ether 45d being the most active with a PPI inhibition IC50 = 7.3 mM.  This is 2x more potent than Pitstop® 2 and 3x more potent than Pitstop 1.

16.
Beilstein J Nanotechnol ; 15: 475-489, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38715710

RESUMEN

A simple approach was developed to synthesize cobalt ferrite nanoparticles/graphene quantum dots (CF/GQDs). The material was prepared from a homogeneous mixture of iron nitrate, cobalt nitrate, and starch at 140, 180 and 200 °C in a 24 h thermal hydrolysis process. The obtained materials were characterised by using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, ultraviolet-visible diffuse reflectance spectroscopy, Fourier-transform infrared spectroscopy, photoluminescence spectroscopy, vibrating-sample magnetometry, and nitrogen adsorption/desorption isotherms. Cobalt ferrite crystals of around 8-10 nm and graphene quantum dots formed directly at 200 °C. Stacking GQDs sheets onto the CF nanoparticles resulted in CF/GQDs nanoparticles. The nanocomposite exhibits satisfactory fluorescent and superparamagnetic properties, which are vital for catalytic applications. The CF/GQDs catalyse significantly the degradation of methylene blue (MB) under visible light. The catalyst can be recycled with an external magnetic field and displays suitable stability. Also, it was reused in three successive experiments with a loss of efficiency of about 5%. The CF/GQDs are considered as an efficient photocatalyst for MB degradation and other dyes.

17.
Data Brief ; 48: 109161, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37153121

RESUMEN

The food delivery apps (FDAs) have facilitated the connection between food service providers and consumers, enabling online ordering through smartphones and offline delivery in Vietnam. The Covid-19 pandemic has significantly impacted the food and beverage industry, accelerating the process of digital transformation and promoting sustainability through online-to-offline service. The usage of FDAs amongst consumers has exhibited a discernible escalation, primarily attributable to its ability to expedite the delivery of food in a hassle-free and convenient manner. Given the ongoing pandemic and the swift increase in demand for online food ordering services, particularly among the younger demographic, it has become imperative to comprehend the drivers that impel consumers to adopt these applications. This article aims to present a dataset pertaining to the decision-making factors that university students in Danang, Vietnam, take into account when they use FDAs and express positive feedback about them on the internet. The survey was conducted between September 2022 and January 2023 and gathered 346 usable responses. The results provide novel perspectives on the adoption of FDAs by university students, which is an emerging technology in the food and beverage sector. This dataset could be useful to various stakeholders, such as service providers, small and medium enterprises (SMEs), and vendors operating on these platforms, as it can help them acquire valuable insights into their customers' preferences and behavior. In addition, the dataset can serve as a basis for conducting comparative research in different universities or countries.

18.
Open Heart ; 10(2)2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-38011990

RESUMEN

OBJECTIVE: This study aimed to assess the incidence of early cancer therapy-related cardiac dysfunction (CTRCD) and the characteristics of left and right heart deformations during anthracycline chemotherapy. METHODS: We prospectively enrolled a cohort of 351 chemotherapy-naïve women with breast cancer and cardiovascular risk factors who were scheduled to receive anthracycline. The left ventricular ejection fraction (LVEF), left ventricular global longitudinal strain (LV-GLS) and right ventricular and left atrial longitudinal strains were evaluated using echocardiography at baseline, before every subsequent cycles and at 3 weeks after the final anthracycline dose. CTRCD was defined as a new LVEF reduction by ≥10 percentage points to an LVEF<50% and/or a new relative decline in GLS by >15% from the baseline value. RESULTS: Eighteen (5.1%) patients had evidence of asymptomatic CTRCD during anthracycline treatment, and 50% developed CTRCD before completing the chemotherapy regimen. In the CTRCD group, while LV-GLS decrease significantly after the first dose of anthracycline, the reduction of right ventricular free-wall longitudinal strain and left atrial reservoir strain were observed after the second dose. Other strain indices could not be used to identify early CTRCD. CONCLUSIONS: Cardiotoxicity appeared soon after the initiation of anthracycline chemotherapy. Among the left-heart and right-heart mechanics, LV-GLS remains the best deformation indicator for detecting early CTRCD.


Asunto(s)
Fibrilación Atrial , Neoplasias de la Mama , Cardiopatías , Disfunción Ventricular Izquierda , Humanos , Femenino , Antraciclinas/efectos adversos , Función Ventricular Izquierda , Volumen Sistólico , Fibrilación Atrial/complicaciones , Disfunción Ventricular Izquierda/diagnóstico , Disfunción Ventricular Izquierda/diagnóstico por imagen , Detección Precoz del Cáncer/efectos adversos , Cardiopatías/diagnóstico , Cardiopatías/diagnóstico por imagen , Neoplasias de la Mama/inducido químicamente , Neoplasias de la Mama/complicaciones , Neoplasias de la Mama/tratamiento farmacológico
19.
Foods ; 12(2)2023 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-36673446

RESUMEN

Four tannin samples extracted from chestnut wood (tannin oenologique, TO), grape (tannin VR grape, TVG), oak gall (tannin galalcool, TG), and oak tree (tannin VR supra elegance, TE) were evaluated for antioxidant and antibacterial activity. The highest total phenolic content (TPC) values were observed in the order of TVG > TG > TE > TO (p < 0.05). The antioxidant activities of all samples were determined in terms of DPPH radical scavenging activity, reducing power, metal-chelating activity, and linoleic acid peroxidation assay. The antioxidant activities of all samples vary and no correlation was observed with the respective TPC values of each sample. Antibacterial activities indicate that all samples showed more or less inhibitory effects against selected Gram-positive and Gram-negative bacteria. Based on antioxidant and antibacterial activity, TO and TVG were selected for the beef mince quality preservation study during refrigerated storage. Both TO and TVG at two different concentrations, 0.25 and 0.5%, could cease the chemical and microbial changes as compared to the control sample. Although total viable count (TVC) did not show a significant difference, the H2S-producing bacteria count was lower in all samples treated with TO and TVG compared to sodium metabisulfite (SMS) and the control sample (p < 0.05). Therefore, TO and TVG could be promising natural food preservatives during refrigerated storage.

20.
Curr Pharm Des ; 29(38): 3050-3059, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37961862

RESUMEN

BACKGROUND: Berberine (BBR), an Eastern traditional medicine, has expressed novel therapeutic activities, especially for chronic diseases like diabetes, hyperlipemia, hypertension, and Alzheimer's disease. However, the low oral bioavailability of BBR has limited the applications of these treatments. Hence, BBRloaded solid lipid nanoparticles (BBR-SLNs) were prepared to improve BBR absorption into systemic circulations via this route. METHODS: BBR-loaded solid lipid nanoparticles (BBR-SLNs) were prepared by ultrasonication and then transformed into solid form via spray drying technique. The size morphology of BBR-SLNs was evaluated by dynamic light scattering (DLS) and scanning electron microscope (SEM). Crystallinity of BBR and interaction of BBR with other excipients were checked by spectroscopic methods. Entrapment efficiency of BBR-SLNs as well as BBR release in gastrointestinal conditions were also taken into account. Lastly, SLN's cytotoxicity for loading BBR was determined with human embryonic kidney cells (HEK293). RESULTS: Stearic acid (SA), glyceryl monostearate (GMS), and poloxamer 407 (P407) were selected for BBRSLNs fabrication. BBR-SLNs had homogenous particle sizes of less than 200 nm, high encapsulation efficiency of nearly 90% and loading capacity of above 12%. BBR-SLN powder could be redispersed without significant changes in physicochemical properties and was stable for 30 days. Spray-dried BBR-SLNs showed a better sustained in vitro release profile than BBR-SLNs suspension and BBR during the initial period, followed by complete dissolution of BBR over 24 hours. Notably, cell viability on HEK293 even increased up to 150% compared to the control sample at 100 µg/mL BBR-unloaded SLNs. CONCLUSION: Hence, SLNs may reveal a promising drug delivery system to broaden BBR treatment for oral administration.


Asunto(s)
Berberina , Nanopartículas , Humanos , Lípidos/química , Berberina/química , Disponibilidad Biológica , Células HEK293 , Nanopartículas/química , Administración Oral , Tamaño de la Partícula , Portadores de Fármacos/química
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