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25 pages, 707 KB  
Review
Port City Regions in Transition: Skills, Inclusion, and Innovative VET Pathways for the Twin Transformation
by Meletios Andrinos, Lidia Greco, Angelos Menelaou, Theodore Metaxas, Emmanouil Nikolaidis, Eva Psatha and Kleanthis Sirakoulis
Sustainability 2026, 18(5), 2538; https://doi.org/10.3390/su18052538 - 5 Mar 2026
Viewed by 582
Abstract
This integrative literature review synthesises five strands of recent scholarships on port city regions (PCRs): (1) their multidimensional transitions, (2) skills foresight and future competences, (3) challenges and reforms in vocational education and training (VET) systems, (4) social inclusion and equity in skills [...] Read more.
This integrative literature review synthesises five strands of recent scholarships on port city regions (PCRs): (1) their multidimensional transitions, (2) skills foresight and future competences, (3) challenges and reforms in vocational education and training (VET) systems, (4) social inclusion and equity in skills development, and (5) innovative VET methodologies in port-adjacent sectors. Drawing on the interdisciplinary academic and policy-oriented literature, this article adopts a qualitative, integrative review approach to examine how the twin green and digital transition is reshaping port city regions and their associated skills ecosystems. The review demonstrates that PCR transitions are not only technical but socio-institutional: while Onshore Power Supplies (OPSs), alternative fuels, and digital platforms are transforming operational landscapes, the success of these innovations depends critically on the adaptive capacity of workers, training systems, and governance arrangements. The article further examines emerging pedagogical approaches in port-adjacent VET, including work-based learning, micro-credentials, and immersive training methods. Taken together, the evidence converges on a central claim: the resilience and sustainability of port city regions depend on integrated skills systems that combine foresight, inclusivity, and pedagogical innovation. Without such systems, decarbonisation and digitalisation risk exacerbating social and spatial inequalities rather than fostering sustainable growth. The article concludes by outlining implications for research, policy, and practice, calling for integrative performance metrics, longitudinal evaluation, and quadruple helix collaboration to support inclusive, competitive, and sustainable port transitions. Full article
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10 pages, 867 KB  
Article
Comparative Analyses of Antiviral Potencies of Second-Generation Integrase Strand Transfer Inhibitors (INSTIs) and the Developmental Compound 4d Against a Panel of Integrase Quadruple Mutants
by Steven J. Smith, Xue Zhi Zhao, Stephen H. Hughes and Terrence R. Burke
Viruses 2025, 17(1), 121; https://doi.org/10.3390/v17010121 - 16 Jan 2025
Cited by 1 | Viewed by 1485
Abstract
Second-generation integrase strand transfer inhibitors (INSTIs) are strongly recommended for people living with HIV-1 (PLWH). The emergence of resistance to second-generation INSTIs has been infrequent and has not yet been a major issue in high-income countries. However, the delayed rollouts of these INSTIs [...] Read more.
Second-generation integrase strand transfer inhibitors (INSTIs) are strongly recommended for people living with HIV-1 (PLWH). The emergence of resistance to second-generation INSTIs has been infrequent and has not yet been a major issue in high-income countries. However, the delayed rollouts of these INSTIs in low- to middle-income countries during the COVID-19 pandemic combined with increased transmission of drug-resistant mutants worldwide are leading to an increase in INSTI resistance. Herein, we evaluated the antiviral potencies of our lead developmental INSTI 4d and the second-generation INSTIs dolutegravir (DTG), bictegravir (BIC), and cabotegravir (CAB) against a panel of IN quadruple mutants. The mutations are centered around G140S/Q148H, including positions L74, E92, and T97 combined with E138A/K/G140S/Q148H. All of the tested INSTIs lose potency against these IN quadruple mutants compared with the wild-type IN. In single-round infection assays, compound 4d retained higher antiviral potencies (EC50 values) than second-generation INSTIs against a subset of quadruple mutants. These findings may advance understanding of mechanisms that contribute to resistance and, in so doing, facilitate development of new INSTIs with improved antiviral profiles. Full article
(This article belongs to the Collection Efficacy and Safety of Antiviral Therapy)
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9 pages, 2214 KB  
Communication
Ag+-Mediated Folding of Long Polyguanine Strands to Double and Quadruple Helixes
by Liat Katrivas, Anna Makarovsky, Benjamin Kempinski, Antonio Randazzo, Roberto Improta, Dvir Rotem, Danny Porath and Alexander B. Kotlyar
Nanomaterials 2024, 14(8), 663; https://doi.org/10.3390/nano14080663 - 11 Apr 2024
Cited by 2 | Viewed by 1911
Abstract
Metal-mediated base pairing of DNA has been a topic of extensive research spanning over more than four decades. Precise positioning of a single metal ion by predetermining the DNA sequence, as well as improved conductivity offered by the ions, make these structures interesting [...] Read more.
Metal-mediated base pairing of DNA has been a topic of extensive research spanning over more than four decades. Precise positioning of a single metal ion by predetermining the DNA sequence, as well as improved conductivity offered by the ions, make these structures interesting candidates in the context of using DNA in nanotechnology. Here, we report the formation and characterization of conjugates of long (kilo bases) homoguanine DNA strands with silver ions. We demonstrate using atomic force microscopy (AFM) and scanning tunneling microscope (STM) that binding of silver ions leads to folding of homoguanine DNA strands in a “hairpin” fashion to yield double-helical, left-handed molecules composed of G-G base pairs each stabilized by a silver ion. Further folding of the DNA–silver conjugate yields linear molecules in which the two halves of the double helix are twisted one against the other in a right-handed fashion. Quantum mechanical calculations on smaller molecular models support the helical twist directions obtained by the high resolution STM analysis. These long guanine-based nanostructures bearing a chain of silver ions have not been synthesized and studied before and are likely to possess conductive properties that will make them attractive candidates for nanoelectronics. Full article
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11 pages, 1342 KB  
Article
Evaluation of Isokinetic Knee Strengths after ACL Reconstruction with Quadrupled Semitendinosus Suspensory Femoral and Tibial Fixation versus Four-Strand Semitendinosus and Gracilis Suspensory Femoral and Tibial Screw Fixation
by Mehmet Halis Cerci, Ali Kerim Yilmaz, Lokman Kehribar, Serkan Surucu, Mahmud Aydin and Mahir Mahirogullari
J. Clin. Med. 2023, 12(12), 4004; https://doi.org/10.3390/jcm12124004 - 12 Jun 2023
Cited by 4 | Viewed by 2512
Abstract
Introduction: The purpose of this study was to demonstrate that patients undergoing ACL reconstruction with quadrupled semitendinosus suspensory femoral and tibial fixation have comparable results in muscle strength and knee function to those undergoing ACL reconstruction with four-strand semitendinosus-gracilis suspensory femoral fixation and [...] Read more.
Introduction: The purpose of this study was to demonstrate that patients undergoing ACL reconstruction with quadrupled semitendinosus suspensory femoral and tibial fixation have comparable results in muscle strength and knee function to those undergoing ACL reconstruction with four-strand semitendinosus-gracilis suspensory femoral fixation and a bioabsorbable tibial interference screw fixation. Materials and Methods: Between 2017 and 2019, 64 patients who were operated on by the same surgeon were included. Patients underwent ACL reconstruction technique with quadrupled semitendinosus suspensory femoral and tibial button fixation in Group 1, and patients underwent ACL reconstruction with coupled four-strand semitendinosus-gracilis suspensory femoral fixation and a bioabsorbable tibial interference screw in Group 2. Evaluation of patients was performed with the Lysholm and Tegner activity scale preoperatively and at the 1st and 6th months postoperatively. At the 6-month visit, isokinetic testing of the operated and non-operated limbs was performed in both groups. Results: There was no significant difference in the age, weight, and BMI values of the patients in Groups 1 and 2 (p < 0.05). According to the strength values of the operated sides of the patients in Group 1 and Group 2, there was no significant difference in the angular velocities of 60° s−1, 180° s−1, and 240° s−1 in both extension and flexion phases between the operated sides of Groups 1 and 2 (p < 0.05). Conclusions: Patients who have ACL reconstruction with quadrupled semitendinosus suspensory femoral and tibial fixation have comparable muscle strength and knee function to those who undergo ACL reconstruction with four-strand semitendinosus-gracilis suspensory femoral fixation and a bioabsorbable tibial interference screw. Full article
(This article belongs to the Special Issue Advances in Knee Surgery and Musculoskeletal Rehabilitation)
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14 pages, 2780 KB  
Article
Helicate versus Mesocate in Quadruple-Stranded Lanthanide Cages: A Computational Insight
by Silvia Carlotto, Lidia Armelao and Marzio Rancan
Int. J. Mol. Sci. 2022, 23(18), 10619; https://doi.org/10.3390/ijms231810619 - 13 Sep 2022
Cited by 8 | Viewed by 2447
Abstract
To drive the synthesis of metallo-supramolecular assemblies (MSAs) and to fully exploit their functional properties, robust computational tools are crucial. The capability to model and to rationalize different parameters that can influence the outcome is mandatory. Here, we report a computational insight on [...] Read more.
To drive the synthesis of metallo-supramolecular assemblies (MSAs) and to fully exploit their functional properties, robust computational tools are crucial. The capability to model and to rationalize different parameters that can influence the outcome is mandatory. Here, we report a computational insight on the factors that can determine the relative stability of the supramolecular isomers helicate and mesocate in lanthanide-based quadruple-stranded assemblies. The considered MSAs have the general formula [Ln2L4]2− and possess a cavity suitable to allocate guests. The analysis was focused on three different factors: the ligand rigidity and the steric hindrance, the presence of a guest inside the cavity, and the guest dimension. Three different quantum mechanical calculation set-ups (in vacuum, with the solvent, and with the solvent and the dispersion correction) were considered. Comparison between theoretical and experimental outcomes suggests that all calculations correctly estimated the most stable isomer, while the inclusion of the dispersion correction is mandatory to reproduce the geometrical parameters. General guidelines can be drawn: less rigid and less bulky is the ligand and less stable is the helicate, and the presence of a guest can strongly affect the isomerism leading to an inversion of the stability by increasing the guest size when the ligand is flexible. Full article
(This article belongs to the Section Molecular Informatics)
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18 pages, 3174 KB  
Article
OsRAD51 Plays a Vital Role in Promoting Homologous Recombination in Rice Meiosis
by Xiaofei Liu, Yiwei Cao, Guijie Du, Chao Zhang, Meng Xu, Zhukuan Cheng, Yi Shen and Hengxiu Yu
Int. J. Mol. Sci. 2022, 23(17), 9906; https://doi.org/10.3390/ijms23179906 - 31 Aug 2022
Cited by 8 | Viewed by 3492
Abstract
Meiotic recombination plays a pivotal role in achieving accurate chromosomal segregation and increasing genetic diversity. In the homologous recombination pathway, the detailed mechanisms of how OsRAD51 and OsDMC1 work in rice meiosis remain to be explored. Here, we obtained different types of mutants [...] Read more.
Meiotic recombination plays a pivotal role in achieving accurate chromosomal segregation and increasing genetic diversity. In the homologous recombination pathway, the detailed mechanisms of how OsRAD51 and OsDMC1 work in rice meiosis remain to be explored. Here, we obtained different types of mutants for Osrad51a1, Osrad51a2, Osdmc1a, and Osdmc1b through CRISPR/Cas9. Both Osrad51a1 and Osrad51a2 exhibited normal vegetative growth and fertility. Osrad51 (Osrad51a1 Osrad51a2) mutant plants show normal vegetative growth but exhibit complete sterility, indicating that OsRAD51A1 and OsRAD51A2 are functionally redundant in rice fertility. In contrast to the wild type, Osrad51 chromosomes are not paired perfectly at pachytene and synaptonemal complex (SC) formation is deficient. Moreover, univalents and multivalent associations were observed at metaphase I, chromosome fragments presented at anaphase I, and crossover formation is basically suppressed in Osrad51 pollen mother cells (PMCs). OsRAD51 foci emerge at leptotene and disappear from late pachytene and chromosome localization of OsRAD51 depends on the formation of double-strand breaks (DSBs). Most OsRAD51 foci can co-localize with OsDMC1 signals. OsRAD51 is essential for the loading of OsDMC1 onto chromosomes, and vice versa. In addition, both OsRAD51 and OsDMC1 can interact with OsFIGL1 and OsBRCA2, two important components in rice meiosis. Moreover, the Osrad51 Osdmc1 (Osrad51a1 Osrad51a2 Osdmc1a Osdmc1b) quadruple mutant PMCs exhibited similar defective phenotypes as Osrad51 in homologous pairing, synapsis, and DSB repair. Taken together, our results suggest that the recombinases DMC1 and RAD51 may functionally depend on each other and play important roles in meiotic recombination during meiosis in rice. Full article
(This article belongs to the Special Issue Rice Molecular Breeding and Genetics)
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23 pages, 551 KB  
Article
Macrostructural Evolution of the Mitogenome of Butterflies (Lepidoptera, Papilionoidea)
by Di Liu, Andrea Basso, Massimiliano Babbucci, Tomaso Patarnello and Enrico Negrisolo
Insects 2022, 13(4), 358; https://doi.org/10.3390/insects13040358 - 6 Apr 2022
Cited by 5 | Viewed by 3819
Abstract
The mitogenome of the species belonging to the Papilionodea (Lepidoptera) is a double stranded circular molecule containing the 37 genes shared by Metazoa. Eight mitochondrial gene orders are known in the Papilionoidea. MIQGO is the plesiomorphic gene order for this superfamily, while other [...] Read more.
The mitogenome of the species belonging to the Papilionodea (Lepidoptera) is a double stranded circular molecule containing the 37 genes shared by Metazoa. Eight mitochondrial gene orders are known in the Papilionoidea. MIQGO is the plesiomorphic gene order for this superfamily, while other mitochondrial arrangements have a very limited distribution. 2S1GO gene order is an exception and is present in several Lycaenidae and one species of Hesperiidae. We studied the macrostructural changes generating the gene orders of butterflies by analysing a large data set (611 taxa) containing 5 new mitochondrial sequences/assemblies and 87 de novo annotated mitogenomes. Our analysis supports a possible origin of the intergenic spacer trnQ-nad2, characterising MIQGO, from trnM. We showed that the homoplasious gene order IMQGO, shared by butterflies, species of ants, beetles and aphids, evolved through different transformational pathways. We identify a complicated evolutionary scenario for 2S1GO in Lycaenidae, characterised by multiple events of duplication/loss and change in anticodon of trnS1. We show that the gene orders ES1GO and S1NGO originated through a tandem duplication random loss mechanism. We describe two novel gene orders. Ampittia subvittatus (Hesperiidae) exhibits the gene order 2FFGO, characterised by two copies of trnF, one located in the canonical position and a second placed in the opposite strand between trnR and trnN. Bhutanitis thaidina (Papilionidae) exhibits the gene order 4QGO, characterised by the quadruplication of trnQ. Full article
(This article belongs to the Section Insect Systematics, Phylogeny and Evolution)
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24 pages, 23223 KB  
Article
CRISPR Editing Enables Consequential Tag-Activated MicroRNA-Mediated Endogene Deactivation
by Panayiota L. Papasavva, Petros Patsali, Constantinos C. Loucari, Ryo Kurita, Yukio Nakamura, Marina Kleanthous and Carsten W. Lederer
Int. J. Mol. Sci. 2022, 23(3), 1082; https://doi.org/10.3390/ijms23031082 - 19 Jan 2022
Cited by 5 | Viewed by 4569
Abstract
Molecular therapies and functional studies greatly benefit from spatial and temporal precision of genetic intervention. We therefore conceived and explored tag-activated microRNA (miRNA)-mediated endogene deactivation (TAMED) as a research tool and potential lineage-specific therapy. For proof of principle, we aimed to deactivate γ-globin [...] Read more.
Molecular therapies and functional studies greatly benefit from spatial and temporal precision of genetic intervention. We therefore conceived and explored tag-activated microRNA (miRNA)-mediated endogene deactivation (TAMED) as a research tool and potential lineage-specific therapy. For proof of principle, we aimed to deactivate γ-globin repressor BCL11A in erythroid cells by tagging the 3′ untranslated region (UTR) of BCL11A with miRNA recognition sites (MRSs) for the abundant erythromiR miR-451a. To this end, we employed nucleofection of CRISPR/Cas9 ribonucleoprotein (RNP) particles alongside double- or single-stranded oligodeoxynucleotides for, respectively, non-homologous-end-joining (NHEJ)- or homology-directed-repair (HDR)-mediated MRS insertion. NHEJ-based tagging was imprecise and inefficient (≤6%) and uniformly produced knock-in- and indel-containing MRS tags, whereas HDR-based tagging was more efficient (≤18%), but toxic for longer donors encoding concatenated and thus potentially more efficient MRS tags. Isolation of clones for robust HEK293T cells tagged with a homozygous quadruple MRS resulted in 25% spontaneous reduction in BCL11A and up to 36% reduction after transfection with an miR-451a mimic. Isolation of clones for human umbilical cord blood-derived erythroid progenitor-2 (HUDEP-2) cells tagged with single or double MRS allowed detection of albeit weak γ-globin induction. Our study demonstrates suitability of TAMED for physiologically relevant modulation of gene expression and its unsuitability for therapeutic application in its current form. Full article
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16 pages, 33220 KB  
Article
PARP1-Inhibition Sensitizes Cervical Cancer Cell Lines for Chemoradiation and Thermoradiation
by Marloes IJff, Gregor G. W. van Bochove, Denise Whitton, Roy Winiarczyk, Celina Honhoff, Hans Rodermond, Johannes Crezee, Lukas J. A. Stalpers, Nicolaas A. P. Franken and Arlene L. Oei
Cancers 2021, 13(9), 2092; https://doi.org/10.3390/cancers13092092 - 26 Apr 2021
Cited by 13 | Viewed by 4392
Abstract
Radiotherapy plus cisplatin (chemoradiation) is standard treatment for women with locoregionally advanced cervical cancer. Both radiotherapy and cisplatin induce DNA single and double-strand breaks (SSBs and DSBs). These double-strand breaks can be repaired via two major DNA repair pathways: Classical Non-Homologous End-Joining (cNHEJ) [...] Read more.
Radiotherapy plus cisplatin (chemoradiation) is standard treatment for women with locoregionally advanced cervical cancer. Both radiotherapy and cisplatin induce DNA single and double-strand breaks (SSBs and DSBs). These double-strand breaks can be repaired via two major DNA repair pathways: Classical Non-Homologous End-Joining (cNHEJ) and Homologous Recombination. Besides inducing DNA breaks, cisplatin also disrupts the cNHEJ pathway. Patients contra-indicated for cisplatin are treated with radiotherapy plus hyperthermia (thermoradiation). Hyperthermia inhibits the HR pathway. The aim of our study is to enhance chemoradiation or thermoradiation by adding PARP1-inhibition, which disrupts both the SSB repair and the Alternative NHEJ DSB repair pathway. This was studied in cervical cancer cell lines (SiHa, HeLa, C33A and CaSki) treated with hyperthermia (42 °C) ± ionizing radiation (2–6 Gy) ± cisplatin (0.3–0.5 µM) ± PARP1-inhibitor (olaparib, 4.0–5.0 µM). Clonogenic assays were performed to measure cell reproductive death. DSBs were analyzed by γ-H2AX staining and cell death by live cell imaging. Both chemoradiation and thermoradiation resulted in lower survival fractions and increased unrepaired DSBs when combined with a PARP1-inhibitor. A quadruple modality, including ionizing radiation, hyperthermia, cisplatin and PARP1-i, was not more effective than either triple modality. However, both chemoradiation and thermoradiation benefit significantly from additional treatment with PARP1-i. Full article
(This article belongs to the Special Issue Preclinical and Translational Research in Gynecological Cancers)
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12 pages, 1370 KB  
Article
Metal Chelating, Inhibitory DNA Damage, and Anti-Inflammatory Activities of Phenolics from Rambutan (Nephelium lappaceum) Peel and the Quantifications of Geraniin and Corilagin
by Yujing Li, Zhaojie Li, Hu Hou, Yongliang Zhuang and Liping Sun
Molecules 2018, 23(9), 2263; https://doi.org/10.3390/molecules23092263 - 5 Sep 2018
Cited by 53 | Viewed by 5726
Abstract
Whereas the preparation and biological properties of rambutan peel phenolics (RPP) were explored in our previous studies, the metal chelating, inhibitory DNA damage, and anti-inflammatory activities of RPP were evaluated and the important phenolics of RPP quantified in this study. Results showed that [...] Read more.
Whereas the preparation and biological properties of rambutan peel phenolics (RPP) were explored in our previous studies, the metal chelating, inhibitory DNA damage, and anti-inflammatory activities of RPP were evaluated and the important phenolics of RPP quantified in this study. Results showed that RPP had high Fe2+ and Cu2+-chelating activities with EC50 of 0.80 mg/mL and 0.13 mg/mL, respectively. RPP effectively decreased the production of hydroxyl radical with IC50 of 62.4 μg/mL. The protective effects of RPP against AAPH-induced DNA damage were also explored. RPP efficiently inhibited peroxyl radical-induced plasmid DNA strand breakage. The anti-inflammatory effects of RPP were determined using a lipopolysaccharide (LPS)-induced RAW 264.7 cell model. RPP significantly inhibited the production of nitric oxide (NO) and controlled the levels of inducible NO synthase mRNA in LPS-induced RAW 264.7 cells. The inhibitory activity increased in a dose-dependent manner. The above bioactivity of RPP was associated with its phenolic content and phenolic profiles. Furthermore, the contents of geraniin and corilagin in RPP were determined by an ultra-high performance liquid chromatography coupled with triple quadruple mass spectrometry (UPLC-QQQ-MS), showing 140.02 and 7.87 mg/g extract dry weight. Thus, RPP has potential applications as a novel nutraceutical and functional food in health promotion. Full article
(This article belongs to the Special Issue Discovery of Active Ingredients from Natural Products)
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20 pages, 7261 KB  
Review
Guanine Quadruplex Electrochemical Aptasensors
by Ana-Maria Chiorcea-Paquim and Ana Maria Oliveira-Brett
Chemosensors 2016, 4(3), 13; https://doi.org/10.3390/chemosensors4030013 - 30 Jul 2016
Cited by 16 | Viewed by 8710
Abstract
Guanine-rich nucleic acids are able to self-assemble into G-quadruplex four-stranded secondary structures, which are found at the level of telomeric regions of chromosomes, oncogene promoter sequences and other biologically-relevant regions of the genome. Due to their extraordinary stiffness and biological role, G-quadruples become [...] Read more.
Guanine-rich nucleic acids are able to self-assemble into G-quadruplex four-stranded secondary structures, which are found at the level of telomeric regions of chromosomes, oncogene promoter sequences and other biologically-relevant regions of the genome. Due to their extraordinary stiffness and biological role, G-quadruples become relevant in areas ranging from structural biology to medicinal chemistry, supra-molecular chemistry, nanotechnology and biosensor technology. In addition to classical methodologies, such as circular dichroism, nuclear magnetic resonance or crystallography, electrochemical methods have been successfully used for the rapid detection of the conformational changes from single-strand to G-quadruplex. This review presents recent advances on the G-quadruplex electrochemical characterization and on the design and applications of G-quadruplex electrochemical biosensors, with special emphasis on the G-quadruplex aptasensors and hemin/G-quadruplex peroxidase-mimicking DNAzyme biosensors. Full article
(This article belongs to the Special Issue Electrochemical Immunosensors and Aptasensors)
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