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- Lymphogranuloma venereum (LGV) ompA-subvariants of the Portuguese collection of Chlamydia trachomatis, 2007–2023Publication . Lodhia, Zohra; Cordeiro, Dora; Correia, Cristina; João, Inês; Carreira, Teresa; Nunes, Alexandra; Ferreira, Rita; Schäfer, Sandra; Aliyeva, Elzara; Portugal, Clara; Monge, Isabel; Gonçalves, Elsa; Matos, Susana; Dias, Ana Paula; Corte-Real, Rita; Vieira, Luís; Gomes, Joao Paulo; Borges, Vítor; Jose Borrego, MariaBackground: Lymphogranuloma venereum (LGV) is a sexually transmitted infection caused by Chlamydia trachomatis ompA-genotypes L1–L3, with increasing numbers of detected cases across Europe. Here, we analysed diversity and temporal distribution of the LGV ompA-subvariants detected in Portugal between 2007 and 2023, in order to better understand the dissemination and diversification landscape of LGV strains. Methods: The collection of the Portuguese National Reference Laboratory includes 1188 LGV ompA-genotyped samples between 2007 and 2023. In-depth analysis of the diversity of LGV ompA-subvariants circulating in Portugal across the years was performed, identifying newly described subvariants and integrating this data in a comprehensive compilation with all representative LGV ompA-subvariants described globally. Results: L2 ompA-variant (L2/434/Bu) was consistently the most frequently detected in our collection, with annual proportions ranging from 34.0% to 82.9%, between 2016 and 2023. L2bV5 was the second most frequent followed by L2b, ranging from 5.0% to 27.9% and 2.6% to 23.7% across the years, respectively, from 2017 to 2023. We highlighted the emergence and considerable increase in circulation of L1-like ompA-subvariants in recent years, representing 13.7% of LGV sequences in 2023. We also identified 13 novel LGV ompA-subvariants that had not been described before, differing by up to three mutations from the respective genotype reference sequences. Conclusions: This study contributes to the worldwide picture of the LGV molecular epidemiology, highlighting the importance of long-term molecular surveillance to monitor the circulation and geographical spread of LGV and to timely identify and track new strains, such as the recently emerging L1-like ompA-subvariants.
- New insights on antibacterial mode of action of blue-light photoactivated berberine and curcumin-antibiotic combinations against Staphylococcus aureusPublication . Gonçalves, Ariana S.C.; Fernandes, José R.; Saavedra, Maria José; Guimarães, Nuno M.; Pereira, Cristiana; Simões, Manuel; Borges, AnabelaAntimicrobial photodynamic inactivation (aPDI), using photosensitisers in combination with antibiotics, is a promising multi-target strategy to address antibiotic resistance, particularly in wound infections. This study aimed to elucidate the antibacterial mode of action of combinations of berberine (Ber) or curcumin (Cur) with selected antibiotics (Ber-Ab or Cur-Ab) under blue light irradiation (420 nm) against Staphylococcus aureus, including methicillin-resistant (MRSA) and methicillin-susceptible (MSSA) strains. Multiple physiological parameters were assessed using complementary assays (fluorometry, epifluorescence microscopy, flame emission and atomic absorption spectroscopy, zeta potential, flow cytometry, and the plate agar method) to examine the effect on ROS production, membrane integrity, DNA damage, motility and virulence factors of S. aureus. Results indicated that blue light photoactivated Ber-Ab and Cur-Ab combinations led to substantial ROS generation, even at low concentrations, causing oxidative stress that severely impacted bacterial membrane integrity (approximately 90 % in MRSA and 40 % in MSSA). Membrane destabilization was further confirmed by elevated intercellular potassium release (≈ 2.00 and 2.40 µg/mL in MRSA and MSSA, respectively). Furthermore, significant DNA damage was observed in both strains (≈ 50 %). aPDI treatment with blue light also reduced S. aureus pathogenicity by impairing motility and inhibiting key virulence factors such as proteases, lipases, and gelatinases, all of which play key roles in the infectious process. Overall, Ber-Ab combinations demonstrated the highest efficacy across all parameters tested, highlighting for the first time the multi-target therapeutic potential of this phytochemical-based aPDI strategy to combat antibiotic-resistant S. aureus infections and improve wound infection treatment outcomes.
- Methods of Extraction, Detection, and Identification of Different Metabolites-A Metabolomics ApproachPublication . Bennici, Giulia; Permatasari, Devi; Al-Younis, Inas; Dhahri, Manel; Pinto, Frederico G.; Uddin, Mohammed J.; Emwas, Abdul-Hamid; Jaremko, Mariusz; Soares, Nelson C.; Soliman, Sameh S.M.; Husseiny, Mohamed I.Metabolic dynamics in attack and defense mechanisms are fascinating topics that illustrate the complex ways organisms adapt to their environments. Attack mechanisms involve several functions, including energy production and metabolic adaptation, where some organisms change their appearance or behavior to balance into their environment. Defense mechanisms involve stress response, immune system activation, repair, and recovery. This chapter provides an overview of the methods applied in modern metabolomics, including single-cell metabolomics and targeted/untargeted approaches, emphasizing how metabolite production rapidly shifts in response to environmental and cellular changes. To effectively monitor these spontaneous effects, it is essential to conduct metabolomics studies with a carefully controlled experimental design. This includes meticulous sample collection, efficient metabolite extraction, and optimization of parameters for the most relevant analytical platform. This chapter outlines the most relevant and commonly used methods for metabolite extraction, aiming to maximize the number of metabolites recovered. This is followed by a summary of the advantages and limitations of the most frequently employed analytical tools, with a particular focus on nuclear magnetic resonance (NMR) and various types of mass spectrometry (MS). Finally, we emphasize the importance of integrating different omics sciences to achieve a comprehensive understanding of biological systems.