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1.
Future Sci OA ; 10(1): FSO921, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38827799

RESUMEN

Aim: Here, an innovative kind of antibacterial nanocomposite film is developed by incorporating graphene oxide and zinc oxide into chitosan matrix. Materials & methods: Our dressing was fabricated using the solution casting method. Fourier transform infrared spectra and TGA-DTG clearly confirmed the structure of film dressing. Results & conclusion: Our results showed the tensile strength and elongation at the break of the films were 20.1 ± 0.7 MPa and 36 ± 10%, respectively. Our fabricated film could absorb at least three-times the fluid of its dry weight while being biocompatible, antibacterial, non-irritant and non-allergic. In addition, it accelerated the healing process of infected wounds by regulating epithelium thickness and the number of inflammatory cells, thus it may be useful for direct application to damaged infected wounds.


In this study, an innovative kind of antibacterial nanocomposite film is developed by incorporating graphene oxide and zinc oxide into chitosan matrix. Our antibacterial wound dressing was fabricated using the solution casting method. Our fabricated film could absorb at least three-times the fluid of its dry weight while being biocompatible, antibacterial, non-irritant and non-allergic. In addition, our film accelerated the healing process of infected wounds by regulating epithelium thickness and the number of inflammatory cells. thus it may be useful for direct application to damaged infected wounds.

2.
Int J Biol Macromol ; 270(Pt 1): 132076, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38705324

RESUMEN

The cross-linked enzyme (CLEs) of Thermomyces lanuginosa lipase (TLL) was prepared in an isocyanide-based multi-component reactions (ICMRs) platform by applying three di-acidic cross-linkers to unveil more factors contributing to the functional properties of CLEs. The linkers were 1,11-undecanedicarboxylic acid, azelaic acid, and adipic acid with 11, 7, and 4 carbon lengths, respectively, providing a proper tool to investigate the effect of linker length on the activity, stability, and selectivity of the resulting CLEs. The immobilization yields of 60-90 % and the specific activities of 168, 88.4 and 49 U/mg were obtained for the CLEs of 1,11-undecanedicarboxylic acid, azelaic acid, adipic acid, respectively. The lower activity of azelaic and adipic acid-mediated CLEs compared to the soluble TLL (110 U/mg) was explained by in silico calculations. The results revealed that as opposed to 1,11-undecanedicarboxylic acid, both linkers tended to penetrate the enzyme active site, thus resulting in a major inhibitory effect on the enzyme functionality. The thermal and co-solvent stability of the immobilized derivatives improved compared to those of free TLL. The selectivity of CLEs was also examined by catalytic release of main omega-3 fatty acids from fish oil, presenting the highest selectivity of 22 for the CLEs of azelaic acid.


Asunto(s)
Reactivos de Enlaces Cruzados , Enzimas Inmovilizadas , Lipasa , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Lipasa/química , Lipasa/metabolismo , Reactivos de Enlaces Cruzados/química , Estabilidad de Enzimas , Eurotiales/enzimología , Adipatos/química , Carbono/química , Ácidos Dicarboxílicos/química
3.
Food Environ Virol ; 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38658427

RESUMEN

In Iran, which is at high risk of the Wild Poliovirus (WPV) and Vaccine-Derived Poliovirus (VDPV) importation due to its neighborhood with two polio endemic countries, Pakistan and Afghanistan, Environmental Surveillance (ES) was established in November 2017. Sistan-Balouchestan province was chosen for the ES due to its vicinity with Pakistan and Afghanistan. Five sewage collection sites in 4 cities (Zahedan, Zabol, Chabahar and Konarak) were selected in the high-risk areas. Since the establishment of ES in November 2017 till the end of 2023, 364 sewage specimens were collected and analyzed. The ES detected polioviruses which have the highest significance for polio eradication program, that is, Wild Poliovirus type 1 (WPV1) and Poliovirus type 2 (PV2). In April and May 2019, three of 364 (0.8%) sewage specimens from Konarak were positive for imported WPV1. According to phylogenetic analysis, they were highly related to WPV1 circulating in Karachi (Sindh province) in Pakistan. PV2 was also detected in 5.7% (21/364) of the sewage specimens, most of which proved to be imported from the neighboring countries. Of 21 isolated PV2s, 7 were VDPV2, of which 5 proved to be imported from the neighboring countries as there was VDPV2 circulating in Pakistan at the time of sampling, and 2 were ambiguous VDPVs (aVDPV) with unknown source. According to the findings of this study, as long as WPV1 and VDPV2 outbreaks are detected in Iran's neighboring countries, there is a definite need for continuation and expansion of the environmental surveillance.

4.
Discov Nano ; 19(1): 32, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38386194

RESUMEN

Activated carbon (AC) is the most common and economically viable adsorbent for eliminating toxic organic pollutants, particularly dyes, from wastewater. Its widespread adoption is due to the simplicity and affordable production of AC, wherein low-cost agricultural wastes, such as durian skin can be used. Converting durian skin into AC presents a promising solution for its solid waste management. However, inherent drawbacks such as its non-selectivity, relatively short lifespan and laborious replacement and recovery processes diminish the overall efficacy of AC as an adsorbent. To address these challenges, the immobilisation of metal nanocatalysts such as silver nanoparticles (AgNPs) is one of the emerging solutions. AgNPs can facilitate the regeneration of the adsorption sites of AC by catalysing the conversion of the adsorbed dyes into harmless and simpler molecules. Nevertheless, the immobilisation of AgNPs on AC surface can be challenging as the pore size formation of AC is hard to control and the nanomaterials can easily leach out from the AC surface. Hence, in this study, we synthesised AC from durian skin (DS) and immobilised AgNPs on the AC-DS surface. Then, we used methylene blue (MB) removal for studying the adsorption capability and recyclability of the AC-DS. In the synthesis of AC-DS, the influences of reaction temperature, activating agent, and acid-washing to its capability in adsorptive removal of  MB in solution were first determined. It was found that 400 °C, KOH activating agent, and the presence of acid-washing (50% of HNO3) resulted in AC-DS with the highest percentage of MB removal (91.49 ± 2.86%). Then, the overall results from three recyclability experiments demonstrate that AC-DS with immobilised AgNPs exhibited higher MB removal after several cycles (up to 6 cycles) as compared to AC-DS alone, proving the benefit of AgNPs for the recyclability of AC-DS. We also found that AgNPs/Citrate@AC-DS exhibited better adsorption capability and recyclability as compared to AgNPs/PVP@AC-DS indicating significant influences of type of stabilisers in this study. This study also demonstrates that the presence of more oxygen-containing functional groups (i.e., carboxyl and hydroxyl functional groups) after acid-washing on AC-DS and in citrate molecules, has greater influence to the performance of AC-DS and AgNPs/Citrate@AC-DS in the removal of MB as compared to the influences of their BET surface area and pore structure. The findings in this study have the potential to promote and serve as a guideline for harnessing the advantages of nanomaterials, such as AgNPs, to enhance the properties of AC for environmental applications.

5.
Sci Total Environ ; 916: 170163, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38242455

RESUMEN

Agricultural Biodiversity dynamics has been evaluated by social metabolism or by landscape structure-function analysis. In this study, by using ELIA modeling, we used both methods in combination to understand how the interplay between social metabolism and landscape structure-function can affect biodiversity pattern distribution. We used energy reinvestment (E) as an indicator of social metabolism and landscape heterogeneity (Le) as an indicator of landscape structure-function. We propose a research hypothesis to analyze biodiversity patterns considering four different clusters identified based on high or low E or Le. As cluster 1, we defined E as high and Le as low and associated natural ecosystems to it. These ecosystems are expected to contain high species abundance but low richness. As cluster 2, both E and Le were defined as high and semi-natural ecosystems were associated to it, where nature friendly farm system developed. In these ecosystems, high species abundance and richness are expected. Cluster 3 with low E and Le was associated intensive farmland, which is due to the simplification of the landscape. Here, low energy reinvestment and landscape heterogeneity confirm that ecosystem services related to biodiversity have been drastically reduced. Lastly, cluster 4 with low E but high Le refers to intensive mosaics of farmland and pasture. In this cluster, the biodiversity richness index is high due to spatial landscape diversity, but the biodiversity abundance index is low due to the lack of energy reinvestment. We evaluate the proposed hypothesis for biodiversity analysis in the Qazvin province, emphasizing the interplay between energy availability and landscape heterogeneity in shaping ecological communities. This study highlights the importance of understanding biodiversity patterns at spatial scale and emphasizes the need for interdisciplinary research to address conservation and sustainability challenges. Our approach would be very useful where there is lack of biodiversity data.


Asunto(s)
Biodiversidad , Ecosistema , Agricultura/métodos , Granjas , Conservación de los Recursos Naturales/métodos
6.
Int J Biol Macromol ; 254(Pt 1): 127817, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37918587

RESUMEN

Various nanoflowers are synthesized for enzyme immobilization. In order to increase the activity of nanoflowers, in this study, 3D flower-like structured organic-inorganic hybrid nanoflowers (hNFs) with various lipases Rhizomucor miehei lipase (RML), Candida antarctica lipase B (CALB), Humicola insolens lipase (HIL), Thermomyces lanuginosus lipase (TLL), Eversa® Transform 2.0 (ET) a genetically modified enzyme derived of TLL and graphene quantum dots (GQDs) were prepared and characterized.Lipase hNFs [lipase-(Cu/Co)3(PO4)2] and lipase@GQDs hNFs [lipase@GQDs-(Cu/Co)3(PO4)2] were straightforwardly prepared through mixing with metal ion (Cu2+or Co2+) aqueous solutions with or without GQDs. The ET@GQDs-(Cu)3(PO4)2 hNFs demonstrated 687 % higher activity than ET-(Cu)3(PO4)2 hNFs and 650 % higher activity than the free ET. Similar results were also observed with other lipase hybrid nanoflowers. For example, TLL@GQDs-(Cu)3(PO4)2 hNFs exhibited a 557 % higher activity than TLL-(Cu)3(PO4)2 hNFs and a 463 % higher activity than free TLL. Additionally, TLL@GQDs-(Co)3(PO4)2 hNFs showed a 141 % higher activity than TLL-(Co)3(PO4)2 hNFs and a 304 % higher activity than free TLL. Upon examining pH and thermal stability, it was revealed that lipase@GQDs hNFs exhibited higher activity compared to free lipase and other hNFs without GQDs. The effect of metal ions, enzyme concentrations and amount of GQDs on the morphology and enzyme activity of the lipase-hNFs was examined.


Asunto(s)
Grafito , Puntos Cuánticos , Lipasa/química , Enzimas Inmovilizadas/química , Interacciones Hidrofóbicas e Hidrofílicas
7.
Proc Natl Acad Sci U S A ; 120(38): e2303224120, 2023 09 19.
Artículo en Inglés | MEDLINE | ID: mdl-37695905

RESUMEN

Cancer genomes are almost invariably complex with genomic alterations cooperating during each step of carcinogenesis. In cancers that lack a single dominant oncogene mutation, cooperation between the inactivation of multiple tumor suppressor genes can drive tumor initiation and growth. Here, we shed light on how the sequential acquisition of genomic alterations generates oncogene-negative lung tumors. We couple tumor barcoding with combinatorial and multiplexed somatic genome editing to characterize the fitness landscapes of three tumor suppressor genes NF1, RASA1, and PTEN, the inactivation of which jointly drives oncogene-negative lung adenocarcinoma initiation and growth. The fitness landscape was surprisingly accessible, with each additional mutation leading to growth advantage. Furthermore, the fitness landscapes remained fully accessible across backgrounds with the inactivation of additional tumor suppressor genes. These results suggest that while predicting cancer evolution will be challenging, acquiring the multiple alterations that drive the growth of oncogene-negative tumors can be facilitated by the lack of constraints on mutational order.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Humanos , Oncogenes/genética , Adenocarcinoma del Pulmón/genética , Mutación , Neoplasias Pulmonares/genética , Transformación Celular Neoplásica , Proteína Activadora de GTPasa p120
8.
Int J Biol Macromol ; 253(Pt 7): 127089, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37774815

RESUMEN

Increasing attention to peptides as prospective therapeutics has created a renaissance in searching for new alternatives to the current peptide synthetic approaches as well as their modification. In this context, it is necessary to develop different approaches for peptide ligation. Using enzymes as a novel strategy and powerful tool for the peptide and protein ligation has recently received a lot of attention. We here designed a fully convergent chemo-enzymatic peptide synthesis (CEPS) process for the synthesis of aviptadil a 28-mer therapeutic peptide with potential therapeutic effects in various medical contexts specially in the treatment of acute respiratory distress syndrome (ARDS) by coupling two peptide segments with four different peptiligase variants in aqueous environments. Our study reveals that peptiligase variants are capable of ligation reaction in 15 min. The overall time of ligation is shorter than those peptides with similar lengths and hinderance to aviptadil which reported for conventional synthesis by full solid-phase peptide synthesis. Yields ranged from 54 % to 76 %.


Asunto(s)
Proteínas , Péptido Intestinal Vasoactivo , Fentolamina , Combinación de Medicamentos
9.
Int J Geriatr Psychiatry ; 38(8): e5972, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37539817

RESUMEN

BACKGROUND: There is growing evidence that vitamin D may be related to mental health. The aim of the current study was to investigate the association of dietary and blood inflammatory factors with mental health disorders in subjects with vitamin D deficiency, shedding further light on the complex interplay of these conditions. METHOD: In this cross-sectional study, 306 subjects completed the validated Depression, Anxiety, and Stress Scale questionnaire to evaluate their depression, anxiety, and stress scores. Dietary inflammatory index (DII) and healthy eating index (HEI) were calculated using a validated 65-item food frequency questionnaire. Blood samples were taken and vitamin D, cytokine, and hs-CRP levels were measured using enzyme-linked immunosorbent assay kits. Platelet to lymphocyte ratio (PLR) and neutrophil to lymphocyte ratio (NLR) were calculated using standard laboratory methods. RESULTS: The subjects were divided into two groups based on their vitamin D levels: a vitamin D < 20 µg/dl group (N = 257) and a vitamin D ≥ 20  µg/dl group (N = 49). Between group analysis revealed that only DII (p = 0.015), platelet (p = 0.04), and hs-CRP (p = 0.015) were significantly different. In adults with vitamin D levels below 20 µg/dl, NLR and DII were significantly higher in subjects with anxiety (p < 0.05), and this relationship remained significant only for NLR after adjusting for age and sex. Additionally, PLR and HEI were significantly different in depressed compared to non-depressed subjects, and this association remained significant only for HEI after adjusting for age and sex. CONCLUSION: In subjects with vitamin D deficiency, increased levels of PLR, NLR, and DII were associated with depression and anxiety, while HEI was negatively associated with depression. These associations were not found in subjects with vitamin D levels ≥20 µg/dl.


Asunto(s)
Proteína C-Reactiva , Deficiencia de Vitamina D , Humanos , Proteína C-Reactiva/análisis , Inflamación , Depresión , Estudios Transversales , Ansiedad , Deficiencia de Vitamina D/complicaciones , Vitamina D
10.
Cureus ; 15(4): e37701, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37206503

RESUMEN

Mediastinal hematomas are thoracic complications often resulting from direct trauma or aortic dissections. Spontaneous non-traumatic mediastinal hematomas are rare. We present a case of spontaneous non-traumatic mediastinal hematoma in a patient on Imatinib therapy for a gastrointestinal stromal tumor (GIST). A 67-year-old female presented to the ER with the chief complaint of constant sharp right shoulder pain that progressed to her chest. The patient was not on any anticoagulants and had not complained of shortness of breath. Under suspicion of a pulmonary embolism, a CT chest scan was performed, and a diagnosis of non-traumatic anterior mediastinal hematoma was confirmed. This case may warrant further investigation into the links between Imatinib use and the formation of mediastinal hematomas.

11.
Org Biomol Chem ; 21(23): 4846-4853, 2023 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-37249163

RESUMEN

A multicomponent enzyme-catalyzed process is suggested for the synthesis of a novel series of 1,3,4-oxadiazole thioether derivatives with yields ranging from 65 to 94%. Novozym 435, the immobilized form of Candida antarctica lipase B (CALB), was found to efficiently catalyze the reaction. The products were evaluated for antitumor activities against two cancer cell lines, HT-29 (human colorectal cancer cell) and HepG2 (human liver cancer cell), by MTT assays. Among them, two compounds exhibited higher antitumor activities, for both cell lines, compared to doxorubicin. In silico molecular docking and computational ADME analysis were performed to propose a mode of action for the anti-cancer activities and to predict drug-likeness, respectively.


Asunto(s)
Antineoplásicos , Oxadiazoles , Humanos , Simulación del Acoplamiento Molecular , Oxadiazoles/farmacología , Biocatálisis , Catálisis , Esterificación , Ensayos de Selección de Medicamentos Antitumorales , Antineoplásicos/farmacología , Relación Estructura-Actividad
13.
Nat Protoc ; 18(5): 1641-1657, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36859613

RESUMEN

Strategies for the covalent immobilization of enzymes depend on the type of functional group selected to perform the coupling reaction, and on the relative importance of selectivity, loading capacity, immobilization time and activity/stability of the resulting immobilized preparation. However, no single strategy is applicable for all covalent immobilization methods or can meet all these criteria, exemplifying the challenge of introducing a versatile process broadly compatible with the residues on the surface of proteins and the functional groups of common linkers. Here, we describe the use of isocyanide-based multi-component reactions for the carrier-bound and carrier-free covalent immobilization of enzymes. Isocyanide-based multi-component reactions can accept a wide variety of functional groups such as epoxy, acid, amine and aldehyde, as well as many commercially available bi-functional linkers, and are therefore suitable for either covalent coupling of enzymes on a solid support or intermolecular cross-linking of enzymes. In this strategy, an isocyanide is directly added to the reaction medium, the enzyme supplies either the exposed amine or carboxylic acid groups, and the support (in carrier-bound immobilization) or the bi-functional cross-linking agent (in carrier-free immobilization) provides another reactive functional group. The protocol offers operational simplicity, high efficiency and a notable reduction in time over alternative strategies, and can be performed by users with expertise in chemistry or biology. The immobilization reactions typically require 1-24 h.


Asunto(s)
Enzimas Inmovilizadas , Proteínas , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Proteínas/química , Aminas/química
14.
3 Biotech ; 13(3): 99, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36866325

RESUMEN

In this study, Candida antarctica lipase A, which has a unique applicability for the conversion of highly branched and bulky substrates, was subjected to immobilization on the flexible nanoporous MIL-53(Fe) by two approaches: covalent coupling and in situ immobilization method. The pre-synthesized support under ultrasound irradiation was incubated with N,N-dicyclohexylcarbodiimide to mediate the covalent attachment between the carboxylic groups on the support surface and amino groups of enzyme molecules. The in situ immobilization in which the enzyme molecules directly were embedded into the metal-organic framework was performed under mild operating conditions in a facile one-step manner. Both immobilized derivatives of the enzyme were characterized by scanning electron microscopy, X-ray diffraction, thermogravimetric analysis, FT-IR spectra, and energy-dispersive X-ray spectroscopy. In the in situ immobilization method, the enzyme molecules were efficiently encapsulated within the support with a high loading capacity (220 ± 5 mg/g support). On the other hand, the covalent attachment resulted in immobilizing much lower concentrations of the enzyme (20 ± 2.2 mg/g support). Although both immobilized derivatives of lipase showed broader pH and temperature tolerance relative to the soluble enzyme, the biocatalyst, which was prepared through in situ method, was more stable at elevated temperatures than the covalently immobilized lipase. Furthermore, in situ immobilized derivatives of Candida antarctica lipase A could be efficiently reused for at least eight cycles (> 70% of retained activity). In contrast, its covalently immobilized counterpart showed a drastic decrease in activity after five cycles (less than 10% of retained activity at the end of 6 rounds).

15.
J Exp Med ; 220(6)2023 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-36995340

RESUMEN

Phagocytosis is a key macrophage function, but how phagocytosis shapes tumor-associated macrophage (TAM) phenotypes and heterogeneity in solid tumors remains unclear. Here, we utilized both syngeneic and novel autochthonous lung tumor models in which neoplastic cells express the fluorophore tdTomato (tdTom) to identify TAMs that have phagocytosed neoplastic cells in vivo. Phagocytic tdTompos TAMs upregulated antigen presentation and anti-inflammatory proteins, but downregulated classic proinflammatory effectors compared to tdTomneg TAMs. Single-cell transcriptomic profiling identified TAM subset-specific and common gene expression changes associated with phagocytosis. We uncover a phagocytic signature that is predominated by oxidative phosphorylation (OXPHOS), ribosomal, and metabolic genes, and this signature correlates with worse clinical outcome in human lung cancer. Expression of OXPHOS proteins, mitochondrial content, and functional utilization of OXPHOS were increased in tdTompos TAMs. tdTompos tumor dendritic cells also display similar metabolic changes. Our identification of phagocytic TAMs as a distinct myeloid cell state links phagocytosis of neoplastic cells in vivo with OXPHOS and tumor-promoting phenotypes.


Asunto(s)
Neoplasias Pulmonares , Macrófagos , Humanos , Macrófagos/metabolismo , Fagocitosis/genética , Neoplasias Pulmonares/patología , Células Mieloides/metabolismo , Estrés Oxidativo , Microambiente Tumoral
16.
Org Biomol Chem ; 21(13): 2742-2747, 2023 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-36916669

RESUMEN

Highly functionalized pyrrolidine-2,3-diones can be synthesized efficiently and stereoselectively under mild conditions using a biocatalytic approach. The reaction led to the formation of new all-carbon quaternary stereocenters from Myceliophthora thermophila laccase (Novozym 51003) catalyzed oxidation of catechols to ortho-quinones and subsequent 1,4-addition with 3-hydroxy-1,5-dihydro-2H-pyrrol-2-ones. The reaction was conducted with various substituents on both reactants, resulting in 13 products in moderate to good yields (42-91%). The same 15 reactions were also tested with K3Fe(CN)6 as a catalyst, but here only one reaction resulted in a product (60% yield).

17.
IET Nanobiotechnol ; 17(3): 204-211, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36734307

RESUMEN

Epidermal growth factor (EGF) can be efficiently used in wound healing process; but the main obstacle of its clinical use is its susceptibility to proteolysis and maintaining its effective concentration in the site of action. In this study, chitosan nanoparticles containing EGF is formulated using a simple method to increase its stability in physiological pH as well as protect its biological activity and effectiveness in wound healing process. Nanoparticles with different ratios of chitosan/EGF were prepared and evaluated in vitro and in vivo. Obtained results showed nanoparticles with 2:1 ratio of chitosan/EGF were able to release 80% of encapsulated protein after 12 h. Cell proliferation study demonstrated that prepared nanoparticles could protect EGF functionality in physiological pH. In vivo results showed that nanoparticles with 2:1 ratio of chitosan/EGF could significantly accelerate the wound closure-rate, re-epithelialisation and collagen deposition. In conclusion, the designed nanoparticles in optimal ratio can be considered as a potential vehicle for EGF delivery to wounds with the aim of improving healing process.


Asunto(s)
Quitosano , Nanopartículas , Factor de Crecimiento Epidérmico , Cicatrización de Heridas , Colágeno
18.
bioRxiv ; 2023 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-36778226

RESUMEN

Cancer genomes are almost invariably complex with genomic alterations cooperating during each step of carcinogenesis. In cancers that lack a single dominant oncogene mutation, cooperation between the inactivation of multiple tumor suppressor genes can drive tumor initiation and growth. Here, we shed light on how the sequential acquisition of genomic alterations generates oncogene-negative lung tumors. We couple tumor barcoding with combinatorial and multiplexed somatic genome editing to characterize the fitness landscapes of three tumor suppressor genes NF1, RASA1, and PTEN, the inactivation of which jointly drives oncogene-negative lung adenocarcinoma initiation and growth. The fitness landscape was surprisingly accessible, with each additional mutation leading to growth advantage. Furthermore, the fitness landscapes remained fully accessible across backgrounds with additional tumor suppressor mutations. These results suggest that while predicting cancer evolution will be challenging, acquiring the multiple alterations required for the growth of oncogene-negative tumors can be facilitated by the lack of constraints on mutational order.

19.
Int J Biol Macromol ; 230: 123140, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36621745

RESUMEN

Organic-inorganic hybrid nanoflowers (hNFs) with commercial protease "Neutrase" is proposed and characterized as efficient and green biocatalysts for promiscuous catalysis in aldol-type and multicomponent reactions. Neutrase hNFs [Neutrase-(Cu/Ca/Co/Mn)3(PO4)2] are straightforwardly prepared through mixing metal ion (Cu2+, Ca2+, Co2+ or Mn2+) aqueous solutions with Neutrase in phosphate buffer (pH 7.4, 10 mM) resulting in precipitation (3 days). The hNFs were characterized by various techniques including scanning electron microscopy (SEM), energy dispersive X-ray (EDX), element mapping, X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). In SEM images, the metal-Neutrase complexes revealed flower-like or granular structures after hybridization. The effect of metal ions and enzyme concentrations on the morphology and enzyme activity of the Neutrase-hNFs was examined. The synthesized Neutrase-Mn hNFs showed superior activity and stability compared to free Neutrase. Traditional organic CC coupling reactions such as aldol condensation, decarboxylative aldol, Knoevenagel, Hantzsch-type reactions and synthesis of 4H-pyran derivatives were used to test the generality and scope of Neutrase promiscuity, while optimizing conditions for the Neutrase-Mn hNF biocatalyst. Briefly, Neutrase-Mn3(PO4)2 hNFs showed excellent enzyme activity, stability and reusability, qualifying as effective reusable catalysts for coupling reactions under mild conditions.


Asunto(s)
Bacillus amyloliquefaciens , Nanoestructuras , Péptido Hidrolasas , Nanoestructuras/química , Aldehídos
20.
Sci Rep ; 12(1): 22326, 2022 12 25.
Artículo en Inglés | MEDLINE | ID: mdl-36567332

RESUMEN

A mild and efficient method was developed for the synthesis of new derivatives of thiazolo[3,2-a] pyrimidin-3(2H)-ones from available starting materials based on the oxidation of catechols to ortho-quinone by Myceliophthora thermophila laccase (Novozym 51,003) and 1,4-addition of active methylene carbon to these in situ generated intermediates in moderate to good yields (35-93%). The structure of the products was confirmed through 1H NMR, 13C NMR, HMBC, HSQC, DEPT-135, and mass spectroscopy techniques. These novel compounds were evaluated as active antitumor agents against human colorectal adenocarcinoma and liver adenocarcinoma cell lines. All compounds displayed potent inhibition activities against the HT-29 cell line with IC50 values of 9.8-35.9 µM, superior to the positive control doxorubicin, and most showed potent anticancer activities against the HepG2 cell line.


Asunto(s)
Antineoplásicos , Ensayos de Selección de Medicamentos Antitumorales , Lacasa , Pirimidinas , Tiazoles , Humanos , Antineoplásicos/química , Antineoplásicos/farmacología , Proliferación Celular/efectos de los fármacos , Células Hep G2 , Células HT29 , Lacasa/química , Estructura Molecular , Relación Estructura-Actividad , Tiazoles/química , Tiazoles/farmacología , Pirimidinas/química , Pirimidinas/farmacología
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