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1.
Ann Bot ; 132(7): 1205-1218, 2023 Dec 30.
Article in English | MEDLINE | ID: mdl-37864498

ABSTRACT

BACKGROUND AND AIMS: Tropaeolaceae (Brassicales) comprise ~100 species native to South and Central America. Tropaeolaceae flowers have a nectar spur, formed by a late expansion and evagination of the fused proximal region of the perianth (i.e. the floral tube). This spur is formed in the domain of the tube oriented towards the inflorescence axis, which corresponds to the adaxial floral region. However, little is known about the molecular mechanisms responsible for the evolution of spurs in Tropaeolaceae. METHODS: In this study, we examined the spatio-temporal expression of genes putatively responsible for differential patterns of cell division between the adaxial and abaxial floral regions in Tropaeolaceae. These genes include previously identified TCP and KNOX transcription factors and the cell division marker HISTONE H4 (HIS4). KEY RESULTS: We found a TCP4 homologue concomitantly expressed with spur initiation and elaboration. Tropaeolaceae possess two TCP4-like (TCP4L) copies, as a result of a Tropaeolaceae-specific duplication. The two copies (TCP4L1 and TCP4L2) in Tropaeolum longifolium show overlapping expression in the epidermis of reproductive apices (inflorescence meristems) and young floral buds, but only TlTCP4L2 shows differential expression in the floral tube at early stages of spur formation, restricted to the adaxial region. This adaxial expression of TlTCP4L2 overlaps with the expression of TlHIS4. Later in development, only TlTCP4L2 is expressed in the nectariferous tissue of the spur. CONCLUSIONS: Based on these results, we hypothesize that Tropaeolaceae TCP4L genes had a plesiomorphic role in epidermal development and that, after gene duplication, TCP4L2 acquired a new function in spur initiation and elaboration. To better understand spur evolution in Tropaeolaceae, it is critical to expand developmental genetic studies to their sister group, the Akaniaceae, which possess simultaneously an independent duplication of TCP4L genes and a spurless floral tube.


Subject(s)
Magnoliopsida , Tropaeolaceae , Tropaeolum , Plant Nectar/metabolism , Tropaeolum/metabolism , Flowers , Magnoliopsida/metabolism , Gene Expression Regulation, Plant
2.
Ultrason Sonochem ; 99: 106545, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37572428

ABSTRACT

This work focuses on a systematic method to produce Ag, Cu, and Ag/Cu metallic nanoparticles (MNPs) in situ assisted with ultrasound on cellulose paper. By tuning the concentration of AgNO3 and CuSO4 salt precursors and ultrasound time, combined with a fixed concentration of ascorbic acid (AA) as a reducing agent, it was possible to control the size, morphology, and polydispersity of the resulting MNPs on cellulose papers. Notably, high yield and low polydispersity of MNPs and bimetallic nanoparticles are achieved by increasing the sonication time on paper samples pre-treated with salt precursors before reduction with AA. Moreover, mechanical analysis on paper samples presenting well-dispersed and distributed MNPs showed slightly decreasing values of Young's modulus compared to neat papers. The strain at break is substantially improved in papers containing solely Ag or Cu MNPs. The latter suggests that the elastic/plastic transition and deformation of papers are tuned by cellulose and MNPs interfacial interaction, as indicated by mechanical analysis. The proposed method provides insights into each factor affecting the sonochemistry in situ synthesis of MNPs on cellulose papers. In addition, it offers a straightforward alternative to scale up the production of MNPs on paper, ensuring an eco-friendly method.

3.
BMJ Open ; 12(3): e056591, 2022 03 17.
Article in English | MEDLINE | ID: mdl-35301211

ABSTRACT

STUDY OBJECTIVES: The marginalisation of undocumented migrants raises concerns about equitable access to COVID-19 vaccination. This study aims to describe migrants' hesitancy about the COVID-19 vaccination during the early phase of the vaccination campaign. SETTING: This multicentric cross-sectional survey was conducted in health facilities providing care to undocumented migrants in the USA, Switzerland, Italy and France in February-May 2021. PARTICIPANTS: Eligibility criteria included age >16 years, being of foreign origin and living without valid residency permit in the country of recruitment. A convenience sample of minimum 100 patients per study site was targeted. PRIMARY AND SECONDARY OUTCOME MEASURES: Data were collected using an anonymous structured questionnaire. The main outcomes were perceived access to the local COVID-19 vaccination programme and demand for vaccination. RESULTS: Altogether, 812 undocumented migrants participated (54.3% Geneva, 17.5% Baltimore, 15.5% Milano and 12.7% Paris). Most (60.9%) were women. The median age was 39 years (interquartile range 1). Participants originated from the Americas (55.9%), Africa (12.7%), Western Pacific (11.2%) Eastern Mediterranean (7.9%), Europe (7.6%) and South-East Asia (4.7%). Overall, 14.1% and 26.2% of participants, respectively, reported prior COVID-19 infection and fear of developing severe COVID-19 infection. Risk factors for severe infection were frequently reported (29.5%). Self-perceived accessibility of COVID-19 vaccination was high (86.4%), yet demand was low (41.1%) correlating with age, comorbidity and views on vaccination which were better for vaccination in general (77.3%) than vaccination against COVID-19 (56.5%). Participants mainly searched for information about vaccination in the traditional and social media. CONCLUSIONS: We found a mismatch between perceived accessibility and demand for the COVID-19 vaccination. Public health interventions using different communication modes should build on trust about vaccination in general to tackle undocumented migrants' hesitancy for COVID-19 vaccination with a specific attention to men, younger migrants and those at low clinical risk of severe infection.


Subject(s)
COVID-19 , Transients and Migrants , Adolescent , Adult , COVID-19/epidemiology , COVID-19/prevention & control , COVID-19 Vaccines/therapeutic use , Cross-Sectional Studies , Female , Humans , Immunization Programs , Male , Vaccination Hesitancy
4.
Biomass Convers Biorefin ; : 1-9, 2022 Jan 12.
Article in English | MEDLINE | ID: mdl-35039789

ABSTRACT

The expansion of the agricultural frontier in the eastern llanos region of Colombia has endangered the moriche palm (Mauritia flexuosa) which has an important ecological function and provides various ecosystem services. In particular, the moriche that grows in this region is wild and has been little studied; therefore, there are no reports of its potential as a source of monounsaturated and polyunsaturated fatty acids, information that could be useful for the conservation of the species. This study performed a physicochemical characterization of the oil extracted from the dried pulp of moriche and identified the fatty acids present in the oil, pulp and peel, seed, and flour of this fruit from the Bita River Basin, Vichada, Colombia. The fatty acid composition was characterized by gas chromatography, including physicochemical tests of interest in the oil according to AOCS protocols. The results showed that the highest fatty acid content was found in the extracted oil, with a distribution of 81.64% unsaturated fat and 18.36% saturated fat. These fats included 79.20% oleic acid (omega-9), 0.26% palmitoleic acid (omega-7), 1.01% linoleic acid (omega-6), 1% linolenic acid (omega-3), 16.91% palmitic acid, and 1.33% stearic acid. We conclude that moriche from Bita Basin is an oleaginous fruit due to its high nutritional value in terms of unsaturated fatty acids and that both the flour and the oil obtained are bioproducts with potential industrial application.

5.
Am J Bot ; 108(8): 1315-1330, 2021 08.
Article in English | MEDLINE | ID: mdl-34458983

ABSTRACT

PREMISE: Floral spurs are key innovations associated with elaborate pollination mechanisms that have evolved independently several times across angiosperms. Spur formation can shift the floral symmetry from radial to bilateral, as it is the case in Tropaeolum, the only member of the Brassicales with floral nectar spurs. The genetic mechanisms underlying both spur and bilateral symmetry in the family have not yet been investigated. METHODS: We studied flower development and morphoanatomy of Tropaeolum longifolium. We also generated a reference transcriptome and isolated all candidate genes involved in adaxial-abaxial differential growth during spur formation. Finally, we evaluated the evolution of the targeted genes across Brassicales and examined their expression in dissected floral parts. RESULTS: Five sepals initiate spirally, followed by five petals alternate to the sepals, five antesepalous stamens, three antepetalous stamens, and three carpels. Intercalary growth at the common base of sepals and petals forms a floral tube. The spur is an outgrowth from the adaxial region of the tube, lined up with the medial sepal. We identified Tropaeolum specific duplications in the TCP3/4L and STM gene lineages, which are critical for spur formation in other taxa. In addition, we found that TM6 (MADS-box), RL2 (RAD-like7), and KN2/6L2 and OSH6L (KNOX1 genes), have been lost in core Brassicales but retained in Tropaeolum. CONCLUSIONS: Three genes are pivotal during the extreme adaxial-abaxial asymmetry of the floral tube, namely, TlTCP4L2 restricted to the adaxial side where the spur is formed, and TlTCP12 and TlSTM1 to the abaxial side, lacking a spur.


Subject(s)
Magnoliopsida , Tropaeolum , Flowers/genetics , Plant Nectar , Pollination
6.
J Control Release ; 337: 179-192, 2021 09 10.
Article in English | MEDLINE | ID: mdl-34274384

ABSTRACT

Glioblastoma is among the most aggressive forms of cancers, with a median survival of just 15-20 months for patients despite maximum clinical intervention. The majority of conventional anti-cancer therapies fail due to associated off-site toxicities which can be addressed by developing target-specific drug delivery systems. Advances in nanotechnology have provided targeted systems to overcome drug delivery barriers associated with brain and other types of cancers. Dendrimers have emerged as promising vehicles for targeted drug and gene delivery. Dendrimer-mediated targeting strategies can be further enhanced through the addition of targeting ligands to enable receptor-specific interactions. Here, we explore the sugar moieties as ligands conjugated to hydroxyl-terminated polyamidoamine dendrimers to leverage altered metabolism in cancer and immune targeting. Using a highly facile click chemistry approach, we modified the surface of dendrimers with glucose, mannose, or galactose moieties in a well-defined manner, to target upregulated sugar transporters in the context of glioblastoma. We show that glucose modification significantly enhanced targeting of tumor-associated macrophages (TAMs) and microglia by increasing brain penetration and cellular internalization, while galactose modification shifts targeting away from TAMs towards galectins on glioblastoma tumor cells. Mannose modification did not alter TAMs and microglia targeting of these dendrimers, but did alter their kinetics of accumulation within the GBM tumor. The whole body biodistribution was largely similar between the systems. These results demonstrate that dendrimers are versatile delivery vehicles that can be modified to tailor their targeting for the treatment of glioblastoma and other cancers.


Subject(s)
Dendrimers , Glioblastoma , Dendrimers/therapeutic use , Drug Delivery Systems , Glioblastoma/drug therapy , Glycosylation , Humans , Macrophages , Tissue Distribution
7.
Int J Mol Sci ; 22(12)2021 Jun 16.
Article in English | MEDLINE | ID: mdl-34208594

ABSTRACT

This article describes the synthesis and characterization of ß-cyclodextrin-based nano-sponges (NS) inclusion compounds (IC) with the anti-tumor drugs melphalan (MPH) and cytoxan (CYT), and the addition of gold nanoparticles (AuNPs) onto both systems, for the potential release of the drugs by means of laser irradiation. The NS-MPH and NS-CYT inclusion compounds were characterized using scanning electron microscopy (SEM), X-ray powder diffraction (XRPD), energy dispersive spectroscopy (EDS), thermogravimetric analysis (TGA), UV-Vis, and proton nuclear magnetic resonance (1H-NMR). Thus, the inclusion of MPH and CYT inside the cavities of NSs was confirmed. The association of AuNPs with the ICs was confirmed by SEM, EDS, TEM, and UV-Vis. Drug release studies using NSs synthesized with different molar ratios of ß-cyclodextrin and diphenylcarbonate (1:4 and 1:8) demonstrated that the ability of NSs to entrap and release the drug molecules depends on the crosslinking between the cyclodextrin monomers. Finally, irradiation assays using a continuous laser of 532 nm showed that photothermal drug release of both MPH and CYT from the cavities of NSs via plasmonic heating of AuNPs is possible.


Subject(s)
Cyclodextrins , Cyclophosphamide/administration & dosage , Drug Carriers , Gold , Melphalan/administration & dosage , Metal Nanoparticles , Chemistry Techniques, Synthetic , Cyclodextrins/chemistry , Drug Carriers/chemistry , Drug Delivery Systems , Drug Liberation/radiation effects , Gold/chemistry , Light , Magnetic Resonance Spectroscopy , Metal Nanoparticles/chemistry , Metal Nanoparticles/ultrastructure , Temperature , Thermogravimetry , Tocopherols , X-Ray Diffraction
8.
Bioeng Transl Med ; 6(2): e10205, 2021 May.
Article in English | MEDLINE | ID: mdl-34027092

ABSTRACT

Glioblastoma is the most common and aggressive form of primary brain cancer, with median survival of 16-20 months and a 5-year survival rates of <5%. Recent advances in immunotherapies have shown that addressing the tumor immune profile by targeting the colony-stimulating factor 1 (CSF-1) signaling pathway of tumor-associated macrophages (TAMs) has the potential to improve glioblastoma therapy. However, such therapies have shown limited successes in clinical translation partially due to lack of specific cell targeting in solid tumors and systemic toxicity. In this study, we present a novel hydroxyl dendrimer-mediated immunotherapy to deliver CSF-1R inhibitor BLZ945 (D-BLZ) from systemic administration selectively to TAMs in glioblastoma brain tumors to repolarize the tumor immune environment in a localized manner. We show that conjugation of BLZ945 to dendrimers enables sustained release in intracellular and intratumor conditions. We demonstrate that a single systemic dose of D-BLZ targeted to TAMs decreases pro-tumor expression in TAMs and promotes cytotoxic T cell infiltration, resulting in prolonged survival and ameliorated disease burden compared to free BLZ945. Our results demonstrate that dendrimer-drug conjugates can facilitate specific, localized manipulation of tumor immune responses from systemic administration by delivering immunotherapies selectively to TAMs, thereby improving therapeutic efficacy while reducing off-target effects.

9.
J Control Release ; 329: 434-444, 2021 01 10.
Article in English | MEDLINE | ID: mdl-33290796

ABSTRACT

Novel delivery strategies are necessary to effectively address glioblastoma without systemic toxicities. Triptolide is a therapy derived from the thunder god vine that has shown potent anti-proliferative and immunosuppressive properties but exhibits significant adverse systemic effects. Dendrimer-based nanomedicines have shown great potential for clinical translation of systemic therapies targeting neuroinflammation and brain tumors. Here we present a novel dendrimer-triptolide conjugate that specifically targets tumor-associated macrophages (TAMs) in glioblastoma from systemic administration and exhibits triggered release under intracellular and intratumor conditions. This targeted delivery improves phenotype switching of TAMs from pro- towards anti-tumor expression in vitro. In an orthotopic model of glioblastoma, dendrimer-triptolide achieved significantly improved amelioration of tumor burden compared to free triptolide. Notably, the triggered release mechanism of dendrimer-mediated triptolide delivery significantly reduced triptolide-associated hepatic and cardiac toxicities. These results demonstrate that dendrimers are a promising targeted delivery platform to achieve effective glioblastoma treatment by improving efficacy while reducing systemic toxicities.


Subject(s)
Dendrimers , Glioblastoma , Phenanthrenes , Dendrimers/therapeutic use , Diterpenes , Epoxy Compounds , Glioblastoma/drug therapy , Humans , Tumor-Associated Macrophages
10.
Int J Mol Sci ; 21(11)2020 Jun 07.
Article in English | MEDLINE | ID: mdl-32517363

ABSTRACT

This article describes the use of ß-cyclodextrin-based carbonate nanosponges (NSs) decorated with superparamagnetic Fe3O4 nanoparticles to study and investigate the potential removal of dinotefuran (DTF) from wastewater. The NS-DTF inclusion compound was characterized by transmission electron microscopy (TEM), energy-dispersive spectroscopy (EDS), UV-visible spectroscopy (UV-VIS), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), X-ray powder diffraction (XRPD) and proton nuclear magnetic resonance (1H-NMR). The adsorption efficiency of NSs was evaluated as function of different contact times. The results confirmed that the NSs have a favourable sorption capacity for the chosen guest, as the polymers exhibited a maximum adsorption of 4.53 × 10-3 mmol/g for DTF. We also found that magnetic NSs show good reusability as they maintain their efficiency after eight adsorption and desorption cycles. Our studies and characterization by means of SEM, TEM, EDS, vibrating sample magnetometer (VSM) and UV-VIS also show that NSs with magnetic properties are excellent tools for insecticide removal from aqueous environments.


Subject(s)
Guanidines/chemistry , Magnetite Nanoparticles/chemistry , Nanocomposites/chemistry , Neonicotinoids/chemistry , Nitro Compounds/chemistry , Wastewater/chemistry , Water Pollutants, Chemical/chemistry , beta-Cyclodextrins/chemistry , Adsorption , Density Functional Theory , Magnetic Resonance Spectroscopy , Magnetite Nanoparticles/ultrastructure , Molecular Structure , Nanocomposites/ultrastructure
11.
Polymers (Basel) ; 10(9)2018 Sep 19.
Article in English | MEDLINE | ID: mdl-30960963

ABSTRACT

This article describes the sorption properties of cyclodextrin polymers (nanosponges; NS) with the pesticides 4-chlorophenoxyacetic acid (4-CPA) and 2,3,4,6-tetrachlorophenol (TCF), including an evaluation of its efficiency and a comparison with other materials, such as granulated activated carbon (GAC). NS-pesticide complexes were characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray powder diffraction (XRPD), proton nuclear magnetic resonance (¹H-NMR), UV⁻VIS, and thermogravimetric analysis (TGA). This confirms the interactions of the guests with nanosponges and shows that the polymers have favorable sorption capacities for chlorinated aromatic guests. Our studies also show that the inclusion complex is predominantly favored for NS/CPA rather than those formed between TCF and NS due to the size of the adsorbate and steric effects. Sorption studies carried with repeated cycles demonstrate that NS polymers could be an improved technology for pollutant removal from aquatic environments, as they are very efficient and reusable materials. Our experiments and characterization by SEM, EDS, UV⁻VIS, and magnetization saturation (VSM) also show that NS is an optimal substrate for the deposition of magnetite nanoparticles, thus improving the usefulness and properties of the polymer, as the nanosponges could be retrieved from aqueous solution with a neodymium magnet without losing its efficiency as a pesticide sorbent.

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