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1.
RSC Adv ; 14(16): 11124-11140, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38606056

RESUMO

Differences in pH between the tumour interstitium and healthy tissues can be used to induce conformational changes in the nanocarrier structure, thereby triggering drug release at the desired site. In the present study, novel pH-responsive nanocarriers were developed by modifying conventional niosomes with hexadecyl-poly(acrylic acid)n copolymers (HD-PAAn). Niosomal vesicles were prepared by the thin film hydration method using Span 60, Span 60/Tween 60 and cholesterol as main constituents, and HD-PAA modifiers of different concentrations (0.5, 1, 2.5, 5 mol%). Next, two model substances, a water-soluble fluorescent dye (calcein) and a hydrophobic agent with pronounced antineoplastic activity (curcumin), were loaded in the aqueous core and hydrophobic membrane of the elaborated niosomes, respectively. Physicochemical properties of blank and loaded nanocarriers such as hydrodynamic diameter (Dh), size distribution, zeta potential, morphology and pH-responsiveness were investigated in detail. The cytotoxicity of niosomal curcumin was evaluated against human malignant cell lines of different origins (MJ, T-24, HUT-78), and the mechanistic aspects of proapoptotic effects were elucidated. The formulation composed of Span 60/Tween 60/cholesterol/2.5% HD-PAA17 exhibited optimal physicochemical characteristics (Dh 302 nm; ζ potential -22.1 mV; high curcumin entrapment 83%), pH-dependent drug release and improved cytotoxic and apoptogenic activity compared to free curcumin.

2.
Int J Mol Sci ; 25(8)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38673783

RESUMO

The medicinal plants of the Asteraceae family are a valuable source of bioactive secondary metabolites, including polyphenols, phenolic acids, flavonoids, acetylenes, sesquiterpene lactones, triterpenes, etc. Under stressful conditions, the plants develop these secondary substances to carry out physiological tasks in plant cells. Secondary Asteraceae metabolites that are of the greatest interest to consumers are artemisinin (an anti-malarial drug from Artemisia annua L.-sweet wormwood), steviol glycosides (an intense sweetener from Stevia rebaudiana Bert.-stevia), caffeic acid derivatives (with a broad spectrum of biological activities synthesized from Echinacea purpurea (L.) Moench-echinacea and Cichorium intybus L.-chicory), helenalin and dihydrohelenalin (anti-inflammatory drug from Arnica montana L.-mountain arnica), parthenolide ("medieval aspirin" from Tanacetum parthenium (L.) Sch.Bip.-feverfew), and silymarin (liver-protective medicine from Silybum marianum (L.) Gaertn.-milk thistle). The necessity to enhance secondary metabolite synthesis has arisen due to the widespread use of these metabolites in numerous industrial sectors. Elicitation is an effective strategy to enhance the production of secondary metabolites in in vitro cultures. Suitable technological platforms for the production of phytochemicals are cell suspension, shoots, and hairy root cultures. Numerous reports describe an enhanced accumulation of desired metabolites after the application of various abiotic and biotic elicitors. Elicitors induce transcriptional changes in biosynthetic genes, leading to the metabolic reprogramming of secondary metabolism and clarifying the mechanism of the synthesis of bioactive compounds. This review summarizes biotechnological investigations concerning the biosynthesis of medicinally essential metabolites in plants of the Asteraceae family after various elicitor treatments.


Assuntos
Asteraceae , Metabolismo Secundário , Asteraceae/metabolismo , Asteraceae/crescimento & desenvolvimento , Biomassa , Plantas Medicinais/metabolismo , Plantas Medicinais/crescimento & desenvolvimento
3.
Dalton Trans ; 53(3): 1087-1098, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38099621

RESUMO

A series of luminescent Cu4I4 clusters with stair-step, cubane, and octahedral geometries supported by a novel type of cyclic As,N-ligand, pyridyl-containing 10-phenoxarsines, were synthesized and characterized by NMR spectroscopy, mass spectrometry, elemental analysis, and single-crystal X-ray diffraction analysis. An unusual arrangement of As,N-bidentate and µ2-iodo ligands was found in the octahedral cluster. The structural diversity of the Cu(I) complexes is reflected in their photophysical properties: the phosphorescence spectra of the compounds display emission in a broad spectral range of 495-597 nm. The complex with the Cu4I4L2 stoichiometry bearing a stair-step Cu4I4 core demonstrates temperature-dependent dual emission. The luminescence properties of all complexes were rationalized by DFT calculations.

4.
Plants (Basel) ; 12(23)2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-38068562

RESUMO

Sideritis scardica Griseb. is a critically endangered Balkan endemic species, known for its antioxidant, neuroprotective and anti-inflammatory properties. The aim of the present study was to detail an efficient protocol for the micropropagation of S. scardica. In vitro cultures were initiated from the shoot tips of 40 days-old in vivo seedlings and the effects of different plant growth regulator treatments were examined. A Murashige and Skoog nutrient medium (MS) containing 1 mg/L zeatin and 0.1 mg/L indole-3-acetic acid (IAA) proved to be the most efficient for shoot multiplication as it produced quality, vigorous shoots with a mean number of six shoots per explant. For the first time, the antioxidant and antitumor activities of extracts from in vitro-obtained plants were evaluated. In vitro cultivated plants grown in the field revealed a higher total polyphenol content (3929.1 ± 112.2 mg GAE/100 g vs. 3563.5 ± 52.8 mg GAE/100 g) and higher ORAC antioxidant activity (1211.6 ± 27.3 µmol TE/g vs. 939.9 ± 52.4 µmol TE/g) than in situ cultivated plants. A comparison of the antitumor activities of extracts from in vitro propagated shoots, field-grown in vitro-obtained plants and in situ plants on HeLa (cervical adenocarcinoma), HT-29 (colorectal adenocarcinoma) and MCF-7 (breast cancer) human cancer cell lines showed that in vitro propagated shoots had a significant concentration-dependent cytotoxic effect on the cervical adenocarcinoma cell line HeLa, while the field-grown in vitro-obtained and in situ-collected samples induced the highest reduction in the viability of the mammary carcinoma cell line MCF-7. In both cases, the cells of the control non-tumor cell line, BALB/3T3, were significantly less affected. The results showed that the in vitro multiplication protocol ensured the obtainment of numerous plants with antioxidant and antitumor potential.

5.
Arthropod Struct Dev ; 77: 101310, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37866256

RESUMO

Regeneration is widespread across all animal taxa, but patterns of its distribution and key factors determining regeneration capabilities stay enigmatic. A comparative approach could shed light on the problem, but its efficacy is limited by the fact that data is only available on a few species from derived taxa. Pycnogonida are nested basally within the Chelicerata. They can shed and replace their walking legs and have a high regeneration capacity. In this work, we carried careful observation on leg appendotomy and regeneration processes in a sea spider under laboratory settings. The limb structure and in vivo observation reveal autotomy as the most likely appendotomy mechanism. High regeneration capabilities were ascertained: an anatomically normal but small leg appeared in a single molting cycle and the full functionality regained in 2-3 cycles. Wound closure after appendotomy in N. brevirostre primarily relies on hemolymph coagulation, which apparently differs from both xiphosurans and crustaceans. Regeneration is provided by proliferation in the leg cutpiece. Regenerative morphogenesis resembles the normal ontogenetic morphogenesis of a walking leg, but accelerated. Unlike in most arthropods, in N. brevirostre, regeneration does not necessarily correspond to the molting cycle, inferring a plesiomorphic state.


Assuntos
Artrópodes , Animais , Extremidades , Morfogênese , Regeneração
6.
Plants (Basel) ; 12(20)2023 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-37896037

RESUMO

The use of nanomaterials in biotechnology for the in vitro propagation of medical plants and the accumulation of certain biologically active metabolites is becoming an efficient strategy. This study aimed to evaluate the influence of the concentration (0, 1, 10, 50, and 100 mg L-1) of two types of nanofibers on the growth characteristics, the antioxidant status, and the production of steviol glycosides in micropropagated Stevia rebaudiana Bert. plantlets. The nanofibers were synthesized by aspartic acid derivatives (L-Asp) Ag salts self-organized into nanofibers with two different molecular structures: monomeric, containing one residue of L-Asp with one hydrophilic head which bonds one Ag ion (NF1-Ag salt); and dimeric, containing two residues of L-Asp with two hydrophilic heads which bond two Ag ions (NF2-Ag salt). An increase in the shoots from the explants' number and length, biomass accumulation, and micropropagation rate was achieved in the plants treated with the NF1-Ag salt in concentrations from 1 to 50 mg L-1 after 30 days of in vitro proliferation compared to the NF2-Ag salt. In contrast, the plants grown on MS media supplemented with NF2-Ag salt exhibited an increase in the level of stevioside, rebaudioside A, and mono- (CQA) and dicaffeoylquinic (DCQA) acids as compared to the NF1-Ag salt.

7.
Trends Biochem Sci ; 48(10): 849-859, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37596196

RESUMO

CENP-A is an essential histone variant that replaces the canonical H3 at the centromeres and marks these regions epigenetically. The CENP-A nucleosome is the specific building block of centromeric chromatin, and it is recognized by CENP-C and CENP-N, two components of the constitutive centromere-associated network (CCAN), the first protein layer of the kinetochore. Recent proposals of the yeast and human (h)CCAN structures position the assembly on exposed DNA, suggesting an elusive spatiotemporal recognition. We summarize the data on the structural organization of the CENP-A nucleosome and the binding of CENP-C and CENP-N. The latter posits an apparent contradiction in engaging the CENP-A nucleosome versus the CCAN. We propose a reconciliatory model for the assembly of CCAN on centromeric chromatin.


Assuntos
Cinetocoros , Nucleossomos , Humanos , Proteína Centromérica A , Cromatina , Saccharomyces cerevisiae
8.
Pharmaceuticals (Basel) ; 16(2)2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-37259331

RESUMO

This study is the first report describing the promising antitumor activity of biologically active compounds isolated from the hemolymph of marine snail Rapana venosa-a fraction with Mw between 50 and 100 kDa and two structural subunits (RvH1 and RvH2), tested on a panel of human breast cell lines-six lines of different molecular subtypes of breast cancer MDA-MB-231, MDA-MB-468, BT-474, BT-549, SK-BR-3, and MCF-7 and the non-cancerous MCF-10A. The fraction with Mw 50-100 kDa (HRv 50-100) showed good antitumor activity manifested by a significant decrease in cell viability, altered morphology, autophagy, and p53 activation in treated cancer cells. An apparent synergistic effect was observed for the combination of HRv 50-100 with cis-platin for all tested cell lines. The combination of HRv 50-100 with cisplatin and/or tamoxifen is three times more effective compared to treatment with classical chemotherapeutics alone. The main proteins in the active fraction, with Mw at ~50 kDa, ~65 kDa, ~100 kDa, were identified by MALDI-MS, MS/MS analyses, and bioinformatics. Homology was established with known proteins with antitumor potential detected in different mollusc species: peroxidase-like protein, glycoproteins Aplysianin A, L-amino acid oxidase (LAAO), and the functional unit with Mw 50 kDa of RvH. Our study reveals new perspectives for application of HRv 50-100 as an antitumor agent used alone or as a booster in combination with different chemotherapies.

9.
Adv Protein Chem Struct Biol ; 135: 243-280, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37061334

RESUMO

The duplication of genetic information is central to life. The replication of genetic information is strictly controlled to ensure that each piece of genomic DNA is copied only once during a cell cycle. Factors that slow or stop replication forks cause replication stress. Replication stress is a major source of genome instability in cancer cells. Multiple control mechanisms facilitate the unimpeded fork progression, prevent fork collapse and coordinate fork repair. Chromatin alterations, caused by histone post-translational modifications and chromatin remodeling, have critical roles in normal replication and in avoiding replication stress and its consequences. This text reviews the chromatin regulators that ensure DNA replication and the proper response to replication stress. We also briefly touch on exploiting replication stress in therapeutic strategies. As chromatin regulators are frequently mutated in cancer, manipulating their activity could provide many possibilities for personalized treatment.


Assuntos
Cromatina , Replicação do DNA , Humanos , Cromatina/genética , Histonas/metabolismo , DNA/metabolismo , Instabilidade Genômica
10.
Plants (Basel) ; 12(8)2023 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-37111815

RESUMO

Clinopodium vulgare L. is a valuable medicinal plant used for its anti-inflammatory, antibacterial and wound-healing properties. The present study describes an efficient protocol for the micropropagation of C. vulgare and compares, for the first time, the chemical content and composition and antitumor and antioxidant activities of extracts from in vitro cultivated and wild-growing plants. The best nutrient medium was found to be Murashige and Skoog (MS) supplemented with 1 mg/L BAP and 0.1 IBA mg/L, yielding on average 6.9 shoots per nodal segment. Flower aqueous extracts from in vitro plants had higher total polyphenol content (29,927.6 ± 592.1 mg/100 g vs. 27,292.8 ± 85.3 mg/100 g) and ORAC antioxidant activity (7281.3 ± 82.9 µmol TE/g vs. 7246.3 ± 62.4 µmol TE/g) compared to the flowers of wild plants. HPLC detected qualitative and quantitative differences in phenolic constituents between the in vitro cultivated and wild-growing plants' extracts. Rosmarinic acid was the major phenolic constituent, being accumulated mainly in leaves, while neochlorogenic acid was a major compound in the flowers of cultivated plants. Catechin was found only in cultivated plants, but not in wild plants or cultivated plants' stems. Aqueous extracts of both cultivated and wild plants showed significant in vitro antitumor activity against human HeLa (cervical adenocarcinoma), HT-29 (colorectal adenocarcinoma) and MCF-7 (breast cancer) cell lines. The best cytotoxic activity against most of the cancer cell lines, combined with the least detrimental effects on a non-tumor human keratinocyte cell line (HaCaT), was shown by the leaf (250 µg/mL) and flower (500 µg/mL) extracts of cultivated plants, making cultivated plants a valuable source of bioactive compounds and a suitable candidate for anticancer therapy.

11.
Pharmaceutics ; 15(3)2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36986651

RESUMO

The discovery of new anticancer drugs with а higher, more specific activity and diminished side effects than the conventional chemotherapeutic agents is a tremendous challenge to contemporary medical research and development. To achieve a pronounced efficacy, the design of antitumor agents can combine various biologically active subunits in one molecule, which can affect different regulatory pathways in cancer cells. We recently demonstrated that a newly synthesized organometallic compound, a ferrocene-containing camphor sulfonamide (DK164), possesses promising antiproliferative activity against breast and lung cancer cells. However, it still encounters the problem of solubility in biological fluids. In this work, we describe a novel micellar form of DK164 with significantly improved solubility in aqueous medium. DK164 was embedded in biodegradable micelles based on a poly(ethylene oxide)-b-poly(α-cinnamyl-ε-caprolactone-co-ε-caprolactone)-b-poly(ethylene oxide) triblock copolymer (PEO113-b-P(CyCL3-co-CL46)-b-PEO113), and the physicochemical parameters (size, size distribution, zeta potential, encapsulation efficiency) and biological activity of the obtained system were studied. We used cytotoxicity assays and flow cytometry to determine the type of cell death, as well as immunocytochemistry to assess the influence of the encapsulated drug on the dynamics of cellular key proteins (p53 and NFkB) and the process of autophagy. According to our results, the micellar form of the organometallic ferrocene derivate (DK164-NP) exhibited several advantages compared to the free substance, such as higher metabolic stability, better cellular uptake, improved bioavailability, and long-term activity, maintaining nearly the same biological activity and anticancer properties of the drug.

12.
Plants (Basel) ; 11(22)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36432747

RESUMO

Primula veris is a valuable medicinal plant species with declining populations, protected in Bulgaria by the Biodiversity Act. The present study aimed to increase its extremely low seed germination rate, starting with seeds originating from two Bulgarian populations, and to set up an ex situ field collection. The stimulation effect of three factors was tested in in vivo and in vitro experiments: seeds treated with gibberellic acid (in different concentrations and exposure time), light quality (white, infrared, red, and blue or dark), and cold stratification. The combination of factors resulted in 36 treatment variants in vivo and 8 treatment variants in vitro. No germination was observed in control treatment variants. The highest germinating rate (95%) was noticed in vivo under blue monochromatic light after seed soaking into 0.2% GA3 for 10 h; however, the best results (55% of well-developed seedlings) were observed with a combination of blue light and 0.3% GA3 for 5 h. Seedlings were successfully strengthened in vermiculite in a phytotron, potted in soil and grown in a greenhouse, and then 75 plants were transferred to the field plot, where most of them bloomed at the first vegetation season. These results are intended to serve as a basis for establishing a pilot agriculture of the species.

13.
Plants (Basel) ; 11(19)2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36235334

RESUMO

The food industry is interested in replacing artificial sweeteners with natural sugars that possess zero calories and carbohydrates and do not cause spikes in blood sugar levels. The steviosides leaves, synthesized at Stevia rebaudiana Bertoni, are 300 times sweeter than common table sugar. Stevia propagation is limited due to the poor viability of the seeds, the long time and low germination rate, and the poor rooting ability of vegetative cuttings. Because of this, an alternative biotechnological method for its reproduction is being studied, such as multiple shoot production through direct organogenesis using nanofibers, formed from a derivative of amino acid valine as a carrier of the biologically active agent silver atoms/particles (NF-1%Ag and NF-2%Ag). The stevia explants were cultured on a medium containing NF-1%Ag and NF-2%Ag at concentrations of 1, 10, 50, and 100 mg L-1. The NF-1%Ag and NF-2%Ag treatment caused hormetic effects on stevia plantlets. At low concentrations of from 1 to 50 mg L-1 of nanofibers, the stimulation of plant growth was observed, with the maximum effect being observed at 50 mg L-1 nanofibers. However, at the higher dose of 100 mg L-1, inhibition of the values of parameters characterizing plant growth was recorded. The presence of nanofibers in the medium stimulates stevia root formatting.

14.
Soft Matter ; 18(29): 5426-5434, 2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35819021

RESUMO

A feasible one pot synthesis of hollow spherical nucleic acids (SNAs) using phospholipid liposomes is reported. These constructs are synthesized in a chemically straightforward process involving formation of unilamellar liposomes, coating the liposomes with a thin cross-linked polymeric layer, and grafting the latter with short (about 20 bases) DNA oligonucleotide strands. They consist of vesicular cores, composed of readily available phospholipid (1,2-dipalmitoyl-sn-glycero-phosphocholine), whereas the strands are deliberately arranged on the surface of the vesicular entities. The initial vesicular structure and morphology are preserved during the coating and grafting reactions. The novel hollow/vesicular SNAs are characterized with a hydrodynamic radius and radius of gyration of 78.3 and 88.5 nm, respectively, and moderately negative (-14.2 mV) ζ potential. They carry thousands (5868) of oligonucleotide strands per vesicle, which are not strongly radially oriented and adopt an unextended conformation as anticipated from the smaller value of the grafting density compared to the critical grafting density at the transition to brush conformation. The constructs are practically devoid of toxicity and exhibit high binding affinity to complementary nucleic acids. Unlike any other nucleic acid structural motif, they cross the cell membrane and enter cells without the need of transfection agents.


Assuntos
Ácidos Nucleicos , Fosfolipídeos , Lipossomos/química , Ácidos Nucleicos/química , Oligonucleotídeos , Fosfolipídeos/química , Polímeros/química , Lipossomas Unilamelares
15.
Biomedicines ; 10(6)2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35740374

RESUMO

The successful design of antitumour drugs often combines in one molecule different biologically active subunits that can affect various regulatory pathways in the cell and thus achieve higher efficacy. Two ferrocene derivatives, DK-164 and CC-78, with different residues were tested for cytotoxic potential on non-small lung cancer cell lines, A549 and H1299, and non-cancerous MRC5. DK-164 demonstrated remarkable selectivity toward cancer cells and more pronounced cytotoxicity against A549. The cytotoxicity of CC-78 toward H1299 was even higher than that of the well-established anticancer drugs cisplatin and tamoxifen, but it did not reveal any noticeable selective effect. DK-164 showed predominantly pro-apoptotic activity in non-small cell lung carcinoma (NSCLC) cells, while CC-78 caused accidental cell death with features characteristic of necrosis. The level of induced autophagy was similar for both substances in cancer cells. DK-164 treatment of A549, H1299, and MRC5 cells for 48 h significantly increased the fluorescence signal of the NFkB (nuclear factor 'kappa-light-chain-enhancer' of activated B-cells) protein in the nucleus in all three cell lines, while CC-78 did not provoke NFkB translocation in any of the tested cell lines. Both compounds caused a significant transfer of the p53 protein in the nucleus of A549 cells but not in non-cancerous MRC5 cells. In A549, DK-164 generated oxidative stress close to the positive control after 48 h, while CC-78 had a moderate effect on the cellular redox status. In the non-cancerous cells, MRC5, both compounds produced ROS similar to the positive control for the same incubation period. The different results related to the cytotoxic potential of DK-164 and CC-78 associated with the examined cellular mechanisms induced in lung cancer cells might be used to conclude the specific functions of the various functional groups in the ferrocene compounds, which can offer new perspectives for the design of antitumour drugs.

16.
Am J Hum Biol ; 34(5): e23695, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34757677

RESUMO

OBJECTIVES: Using prenatally fixed dermatoglyphics features as markers of prenatal sex development is limited due to insufficient knowledge on their sex differences. This study aims to examine more thoroughly sex differences in radioulnar contrasts. METHODS: Fingerprints of 360 females and 331 males from four samples of different ethnic backgrounds (Czechs, Slovaks, Vietnamese and Lusatian Sorbs) were studied. On both hands, finger ridge counts were recorded, and all possible radioulnar contrasts were computed as a difference between ridge count at a radial position minus ridge count at a respective ulnar position on the hand. Radioulnar contrasts with population-congruent and numerically large dimorphism were selected and the dimorphism of the selected radioulnar contrasts was then tested using nonparametric analysis of variance. RESULTS: Greater dimorphism of radioulnar contrasts occurred on the right hand than on the left hand. Population congruent direction and relatively strong dimorphism (Cohen's d greater than 0.3) was found in six radioulnar contrasts on the right hand, all of which involved the radial ridge count of the 2nd finger. Of these, the highest average dimorphism was observed for the difference between the radial ridge count of the 2nd finger and the ulnar ridge count of the 4th finger (2r4u contrast), where the average effect size from all four population samples was comparable to a published average effect size of the 2D:4D finger length ratio. CONCLUSION: We propose that 2r4u contrast of ridge counts could serve as a marker of prenatal sexual development targeting a temporally narrow developmental window.


Assuntos
Dermatoglifia , Caracteres Sexuais , Biomarcadores , Etnicidade , Feminino , Dedos/anatomia & histologia , Humanos , Masculino , Gravidez , Desenvolvimento Sexual , Vitaminas
17.
Plants (Basel) ; 12(1)2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36616282

RESUMO

Stevia rebaudiana Bertoni is a valuable plant whose products are increasingly used in medicine, pharmacy and the food industry. This necessitates the use of biotechnological approaches for its mass propagation. Establishing optimal conditions for in vitro cultivation is essential for obtaining high biomass and secondary metabolites production. A large number of articles considering the role of plant growth regulators and other additives in the culture medium in the growth and development of Stevia are available in the literature. However, there are no summarized data about the use of nanoparticles in Stevia tissue cultures. Therefore, this review also includes the research conducted so far on the effect of nanoparticles on Stevia micropropagation. Furthermore, the influence of different elicitors on secondary metabolite production and antioxidant activity of in vitro-cultivated Stevia plants have been discussed. By referring to the collected literature, we concluded that biotechnological approaches applied to S. rebaudiana cultivation might improve the agronomic traits of plants and steviol glycosides production.

18.
Environ Sci Eur ; 34(1): 58, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37128271

RESUMO

Background: The implementation of the Sustainable Development Goals (SDGs) requires much planning and the provision of resources, especially regarding the necessary investments, technologies and infrastructures needed. Yet, it is presently unclear how available these elements are, what gaps exist, what changes have taken place in terms of their availability since the adoption of the SDGs and what their requirements will be in the future. The knowledge gap has become even more concerning because of the impact of the COVID-19 pandemic. Using a bibliometric analysis, an assessment of the global progress of SDG implementation and requirements, identifying challenges through the development of a matrix, and a set of 11 case studies to triangulate the holistic analysis, an assessment of the global progress of the SDGs implementation and the impact of the COVID-19 pandemic on this process was carried out. Results: The findings suggest that the scope and width of resources limitation are currently undermining the implementation of the SDGs. Apart from the fact that the pace of progress has been insufficient, the potential of the SDGs in pursuing sustainability and improving life quality is not fully realised. This trend suggests that a substantial acceleration of the efforts is needed, especially for the five SDGs whose progress since 2015 has not been optimal, namely SDG2, SDG11, SDG13, SDG15, and SDG16, while SDG3, SDG7, SDG9, SDG14, and SDG17 show signs of progress. The case studies showed that different industries have dissimilar effects on achieving the SDGs, with the food sector correlating with 15 SDGs, as opposed to the energy sector correlating with 6 SDGs. Accordingly, the priority level assessment in terms of achieving the SDGs, points to the need to further advance the above-mentioned five SDGs, i.e., 2, 11, 13, 15 and 16. Conclusions: This study fills in a knowledge gap in respect of the current need for and availability of investments, new technologies, and infrastructures to allow countries to pursue the SDGs. It is suggested that this availability is rather limited in specific contexts. In respect of the needs to be addressed, these include resource-related constraints, limited technologies and infrastructures, affecting SDG2, SDG11, SDG13, SDG15, and SDG16, whose progress needs to be enhanced. Since the global progress in the process of implementation of the SDGs depends directly and indirectly on addressing the resource gaps, it is suggested that this topic be further investigated, so that the present imbalances in the three dimensions of sustainable development: the economic, social and environmental, be adequately addressed. Supplementary Information: The online version contains supplementary material available at 10.1186/s12302-022-00629-9.

19.
Int J Mol Sci ; 22(17)2021 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-34502513

RESUMO

Gene therapy is an attractive therapeutic method for the treatment of genetic disorders for which the efficient delivery of nucleic acids into a target cell is critical. The present study is aimed at evaluating the potential of copolymers based on linear polyglycidol to act as carriers of nucleic acids. Functional copolymers with linear polyglycidol as a non-ionic hydrophilic block and a second block bearing amine hydrochloride pendant groups were prepared using previously synthesized poly(allyl glycidyl ether)-b-polyglycidol block copolymers as precursors. The amine functionalities were introduced via highly efficient radical addition of 2-aminoethanethiol hydrochloride to the alkene side groups. The modified copolymers formed loose aggregates with strongly positive surface charge in aqueous media, stabilized by the presence of dodecyl residues at the end of the copolymer structures and the hydrogen-bonding interactions in polyglycidol segments. The copolymer aggregates were able to condense DNA into stable and compact nanosized polyplex particles through electrostatic interactions. The copolymers and the corresponding polyplexes showed low to moderate cytotoxicity on a panel of human cancer cell lines. The cell internalization evaluation demonstrated the capability of the polyplexes to successfully deliver DNA into the cancer cells.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Terapia Genética/métodos , Propilenoglicóis/química , Linhagem Celular , DNA/química , Técnicas de Transferência de Genes , Vetores Genéticos/genética , Humanos , Polímeros/química , Propilenoglicóis/farmacologia , Transfecção
20.
Macromol Biosci ; 21(2): e2000352, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33283423

RESUMO

Physicochemical characteristics and biological performance of polyplexes based on two identical copolymers bearing tertiary amino or quaternary ammonium groups are evaluated and compared. Poly(2-(dimethylamino)ethyl methacrylate)-b-poly(oligo(ethylene glycol) methyl ether methacrylate) block copolymer (PDMAEMA-b-POEGMA) is synthesized by reversible addition fragmentation chain transfer polymerization. The tertiary amines of PDMAEMA are converted to quaternary ammonium groups by quaternization with methyl iodide. The two copolymers spontaneously formed well-defined polyplexes with DNA. The size, zeta potential, molar mass, aggregation number, and morphology of the polyplex particles are determined. The parent PDMAEMA-b-POEGMA exhibits larger buffering capacity, whereas the corresponding quaternized copolymer (QPDMAEMA-b-POEGMA) displays stronger binding affinity to DNA, yielding invariably larger in size and molar mass particles bearing greater number of DNA molecules per particle. Experiments revealed that QPDMAEMA-b-POEGMA is more effective in transfecting pEGFP-N1 than the parent copolymer, attributed to the larger size, molar mass, and DNA cargo, as well as to the effective cellular traffic, which dominated over the enhanced ability for endo-lysosomal escape of PDMAEMA-b-POEGMA.


Assuntos
Aminas/química , Fenômenos Químicos , Técnicas de Transferência de Genes , Vetores Genéticos/metabolismo , Metacrilatos/química , Nylons/química , Soluções Tampão , Morte Celular , Linhagem Celular Tumoral , Células HEK293 , Humanos , Hidrodinâmica , Concentração Inibidora 50 , Tamanho da Partícula , Polietilenoglicóis/química , Eletricidade Estática , Ultracentrifugação
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