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There are known methods to manage the population dynamics of wild and sterile mosquitoes by releasing genetically engineered sterile mosquitoes. Even if a two-dimensional system of ordinary differential equations is considered as a simple mathematical model for developing release strategies, fully understanding the global behavior of the solutions is challenging, due to the fact that the probability of mating is ratio-dependent. In this paper, we combine a geometric approach called the time-scale transformation and blow-up technique with the center manifold theorem to provide a complete understanding of dynamical systems near the origin. Then, the global behavior of the solution of the two-dimensional ordinary differential equation system is classified in a two-parameter plane represented by the natural death rate of mosquitoes and the sterile mosquito release rate. We also offer a discussion of the sterile mosquito release strategy. In addition, we obtain a better exposition of the previous results on the existence and local stability of positive equilibria. This paper provides a framework for the mathematical analysis of models with ratio-dependent terms, and we expect that it will theoretically withstand the complexity of improved models.
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Culicidae , Dinâmica Populacional , Animais , Culicidae/fisiologia , Mosquitos Vetores/fisiologia , Feminino , Controle de Mosquitos/métodos , Masculino , Modelos Biológicos , Simulação por Computador , Animais Geneticamente Modificados , Algoritmos , Controle Biológico de Vetores/métodos , Modelos TeóricosRESUMO
Age-related macular degeneration (AMD) and related macular dystrophies (MDs) primarily affect the retinal pigment epithelium (RPE) in the eye. A hallmark of AMD/MDs that drives later-stage pathologies is drusen. Drusen are sub-RPE lipid-protein-rich extracellular deposits, but how drusen forms and accumulates is not known. We utilized human induced pluripotent stem cell (iPSC)-derived RPE from patients with AMD and three distinct MDs to demonstrate that reduced activity of RPE-secreted matrix metalloproteinase 2 (MMP2) contributes to drusen in multiple maculopathies in a genotype-agnostic manner by instigating sterile inflammation and impaired lipid homeostasis via damage-associated molecular pattern molecule (DAMP)-mediated activation of receptor for advanced glycation end-products (RAGE) and increased secretory phospholipase 2-IIA (sPLA2-IIA) levels. Therapeutically, RPE-specific MMP2 supplementation, RAGE-antagonistic peptide, and a small molecule inhibitor of sPLA2-IIA ameliorated drusen accumulation in AMD/MD iPSC-RPE. Ultimately, this study defines a causal role of the MMP2-DAMP-RAGE-sPLA2-IIA axis in AMD/MDs.
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BACKGROUND: Vector-borne diseases cause morbidity and mortality globally. However, some areas are more impacted than others, especially with climate change. Controlling vectors remains the primary means to prevent these diseases, but new, more effective tools are needed. The World Health Organization (WHO) prioritized evaluating novel control methods, such as sterile insect technique (SIT) for control of Aedes-borne diseases. In response, a multiagency partnership between the U.S. Centers for Disease Control and Prevention (CDC), the Special Programme for Research and Training in Tropical Diseases (TDR), WHO, and the International Atomic Energy Agency (IAEA) supported the operational implementation and evaluation of SIT against Aedes aegypti and arboviral diseases in the Pacific through a consortium of regional partners (PAC-SIT Consortium). MAIN TEXT: A workshop was held from 2 to 6 May 2023, during which PAC-SIT country participants, researchers, and stakeholders in SIT, scientific advisory committee members, and organizational partners came together to review the principles and components of SIT, share experiences, visit field sites and the SIT facility, and officially launch the PAC-SIT project. Working in groups focused on entomology, epidemiology, and community engagement, participants addressed challenges, priorities, and needs for SIT implementation. CONCLUSIONS: The PAC-SIT workshop brought together researchers and stakeholders engaged in evaluating SIT for arboviral diseases in the Pacific region and globally. This training workshop highlighted that many countries are actively engaged in building operational capacities and phased testing of SIT. The workshop identified a key need for robust larger-scale studies tied with epidemiological endpoints to provide evidence for the scalability and impact on mosquito-borne diseases.
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Aedes , Infecções por Arbovirus , Controle de Mosquitos , Animais , Infecções por Arbovirus/prevenção & controle , Infecções por Arbovirus/epidemiologia , Infecções por Arbovirus/transmissão , Controle de Mosquitos/métodos , Humanos , Ilhas do Pacífico/epidemiologia , Mosquitos Vetores , Doenças Transmitidas por Vetores/prevenção & controle , Doenças Transmitidas por Vetores/epidemiologia , Fortalecimento Institucional/métodos , Doenças Transmitidas por MosquitosRESUMO
The Sam (Sterile alpha motif) domain of the lipid phosphatase Ship2 (Ship2-Sam) is engaged by the Sam domain of the receptor tyrosine kinase EphA2 (EphA2-Sam) and, this interaction is principally linked to procancer effects. Peptides able to hinder the formation of the EphA2-Sam/Ship2-Sam complex could possess therapeutic potential. Herein, by employing the FoldX software suite, we set up an in silico approach to improve the peptide targeting of the so-called Mid Loop interface of Ship2-Sam, representing the EphA2-Sam binding site. Starting from a formerly identified peptide antagonist of the EphA2-Sam/Ship2-Sam association, first, the most stabilizing mutations that could be inserted in each peptide position were predicted. Then, they were combined, producing a list of potentially enhanced Ship2-Sam ligands. A few of the in silico generated peptides were experimentally evaluated. Interaction assays with Ship2-Sam were performed using NMR and BLI (BioLayer Interferometry). In vitro assays were conducted as well to check for cytotoxic effects against both cancerous and healthy cells, and also to assess the capacity to regulate EphA2 degradation. This study undoubtedly enlarges our knowledge on how to properly target EphA2-Sam/Ship2-Sam associations with peptide-based tools and provides a promising strategy that can be used to target any protein-protein interaction.
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Peptídeos , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases , Receptor EphA2 , Motivo Estéril alfa , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/metabolismo , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/genética , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/química , Humanos , Receptor EphA2/metabolismo , Receptor EphA2/química , Receptor EphA2/genética , Peptídeos/química , Peptídeos/metabolismo , Peptídeos/farmacologia , Ligantes , Ligação Proteica , Sítios de LigaçãoRESUMO
Background: Osgood-Schlatter disease (OSD) belongs to the group of sterile bone necrosis and mainly affects athletically active children. The pathogenesis of OSD is currently not fully understood, so the purpose of this study was to evaluate the concentrations of selected matrix metalloproteinases (MMPs)-MMP-2, MMP-3, MMP-7, MMP-9, MMP-10 and MMP-26 in patients diagnosed with OSD compared to patients with diseases other than sterile bone necrosis Methods: The study group included 140 patients with OSD, while the control group contained 100 patients with knee pain unrelated to sterile bone necrosis. The MMPs tested were determined by an enzyme-linked immunosorbent assay in plasma. Results: Patients with OSD had higher concentrations of MMP-2 and MMP-9 compared to the control group. The concentrations of MMP-7, MMP-10 and MMP-26 were lower in affected children. High values of diagnostic parameters-diagnostic accuracy (AC), sensitivity (SE), specificity (SP) and area under curve (AUC)-were obtained for MMP-7, MMP-9 and MMP-26. Conclusions: The collected results convince that MMP-7, MMP-9 and MMP-26 can be consider as a differential ancillary test between OSD and other knee pain and may be involved in the pathogenesis of this condition.
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BACKGROUND: Patients with central lines face an increased risk of developing bacteremia. Preventing late-onset catheter-related infections relies on implementing various measures during manipulations of the catheter hub of central lines (e.g., during connections, disconnections, blood withdrawals, pulsed rinses, or injections performed at the first connection after the central catheter). French guidelines include, among these measures, the requirement to put on sterile gloves immediately before proximal manipulation to help prevent contamination of the catheter hub during preparation. To our knowledge, no study has reported compliance with wearing sterile gloves during these manipulations, nor the impact of not wearing sterile gloves on the cleanliness of the fingers of healthcare workers (HCWs) just before manipulating the connectors. METHODS: We conducted a two-part study to assess compliance with sterile gloving and to provide direct microbiological evidence of bacterial contamination on HCWs' hands immediately before the manipulation of central lines when sterile gloving is not used. First, the use of sterile gloves was observed during proximal manipulations of central lines using a standardized grid. Second, we examined the microbial flora present on the fingers of each observed HCW just before proximal manipulation. RESULTS: A total of 260 HCWs from 35 healthcare institutions were observed during proximal manipulation. The HCWs were distributed into three groups: 188 used sterile gloves (72%), 23 used nonsterile gloves (9%), and 49 did not wear gloves (19%). The swabbing of the fingertips revealed microbial cultures from 72 samples (28%). A total of 97 microorganisms were identified, all of which are well-recognized agents responsible for catheter-related bacteremia, predominantly coagulase-negative staphylococci (n = 36) and Bacillus sp. (n = 31). Fingertip contamination was lower for HCWs wearing sterile gloves (27/188; 14%) than for those wearing nonsterile gloves (12/23; 52%) or not wearing gloves (33/49; 67%) (p < 0.001). The contaminants were similar across the three groups. CONCLUSIONS: Our data support the positive impact of sterile gloving in ensuring clean fingertips during proximal manipulation of central lines, a key measure in preventing late-onset catheter-related bacteremia. The contamination of sterile gloves in one out of seven HCWs highlights the need for a clean care environment and minimal contact with the patient's skin and surroundings during proximal manipulation.
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Infecções Relacionadas a Cateter , Humanos , Infecções Relacionadas a Cateter/prevenção & controle , Cateterismo Venoso Central/efeitos adversos , Pessoal de Saúde , Luvas Cirúrgicas/microbiologia , Cateteres Venosos Centrais/microbiologia , França , Contaminação de Equipamentos/prevenção & controle , Luvas Protetoras , Fidelidade a Diretrizes , Infecção Hospitalar/prevenção & controle , Controle de Infecções/métodos , Feminino , MasculinoRESUMO
AIMS: A wide range of vector control programs rely on the efficient production and release of male mosquito. Asaia bacteria are described as potential symbionts of several mosquito species but their relationship with Aedes aegypti has never been rigorously tested. Here we aimed to quantify the benefits of three Asaia species on host development in Ae. aegypti, and the ability of these bacteria to form a stable symbiotic association with growing larvae. METHODS AND RESULTS: In order to disentangle direct and indirect effects of Asaia inoculation on host development, experiments used insects with an intact microbiome and those reared in near-aseptic conditions, while we characterized bacterial communities and Asaia densities with culture dependent and independent methods (16S rRNA amplicon sequencing). Neonate larvae were inoculated with Asaia spp. for 24 hours, or left as uninoculated controls, all were reared on sterile food. Aseptic larvae were produced by surface sterilization of eggs. Although all Asaia were transient members of the gut community, two species accelerated larval development relative to controls. The two mutualistic species had lasting impacts on the larval microbiome, largely by altering the relative abundance of dominant bacteria, namely Klebsiella and Pseudomonas. Axenic larvae were dominated by Asaia when inoculated with this species but showed slower development than conventionally reared insects, indicating that Asaia alone could not restore normal development. CONCLUSIONS: Our results reveal Asaia as a poor mutualist for Ae. aegypti, but with a species-specific positive effect on improving host performance mediated by interactions with other bacteria.
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Background Adherence to aseptic protocols and proper sterilization is critical for optimal patient recovery post-surgery. The standard procedure for donning sterile surgical gloves helps manage infection risk and maintain surgical site cleanliness by following aseptic principles. This study evaluates adherence to these protocols among young surgeons at a tertiary care hospital in Sudan. Methods This prospective audit included 42 young residents and house officers at a tertiary care hospital in Sudan, following ethical clearance. Compliance with sterile surgical glove-donning practices was assessed using the World Health Organization (WHO) pre- and post-intervention criteria. Participants were observed in the operating room without prior notice. The intervention comprised a video presentation and a live demonstration. Results Pre-intervention adherence to standard criteria for donning sterile surgical gloves was 73.4% (n= 31). This rate increased significantly to 91.4% (n= 38) following the intervention and showed marked improvement. Conclusion The audit demonstrated a significant improvement in adherence to donning sterile surgical gloves practices after the intervention. Implementing WHO guidelines effectively enhances compliance, reduces infection risks, and increases awareness of aseptic practices.
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Introduction: Pulmonary ischemia-reperfusion (IR) injury (IRI) plays a significant role in various lung disorders and is a key factor in the development of primary graft dysfunction following lung transplantation. Hemopexin (Hx) is the major serum scavenger protein for heme, which is a prooxidant and pro-inflammatory compound. In the current study, we hypothesized that Hx could confer beneficial effects in sterile inflammation induced by IR-mediated lung injury. Methods: To examine this hypothesis, we administered Hx in an experimental mouse model of unilateral lung IRI. Results: Our results demonstrate that treatment with Hx alleviated histopathological signs of inflammation in ischemic lungs, as evidenced by a reduction in the number of infiltrating neutrophils and decreased levels of perivascular edema. In addition, thrombotic vaso-occlusion in pulmonary blood vessels of IRI lungs was reduced by Hx. Immunohistochemical analysis revealed that Hx inhibited the up-regulation of heme oxygenase-1, an enzyme highly induced by heme, in ischemic lungs. Finally, Hx administration caused a decrease in the levels of circulating B- and CD8+ T-lymphocytes in the peripheral blood of mice with pulmonary IRI. Conclusion: These findings suggest that the serum heme scavenger protein Hx holds therapeutic promise in alleviating lung IRI-mediated sterile inflammation. Thus, Hx may represent a preemptive therapeutic approach in IR-related lung disorders such as primary graft dysfunction in lung transplantation.
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Modelos Animais de Doenças , Hemopexina , Traumatismo por Reperfusão , Animais , Hemopexina/metabolismo , Hemopexina/farmacologia , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , Camundongos , Masculino , Heme Oxigenase-1/metabolismo , Pulmão/patologia , Pulmão/imunologia , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Camundongos Endogâmicos C57BL , Inflamação , Lesão Pulmonar/etiologia , Lesão Pulmonar/tratamento farmacológico , Proteínas de MembranaRESUMO
Primordial germ cells (PGCs) are stem cells, from which only gametes develop. In birds, the female sex is heterogametic, thus female gene conservation necessitates preservation of PGCs. PGC transplantation can generate germline chimeras in a host organism and develop into gametes. However, competition between host and transplanted PGCs hinder efficiency of germline chimera generation. We hypothezised that in sterile hybrid recipients with no germ cells of its own, transplanted donor PGCs may exclusively form gametes. Advantages of sterile hybrids as host for PGCs is compliant with many national regulations on genetically modified organisms and technically simpler procedure than the use of busulphan. Therefore, we investigated whether sterile interspecific hybrids may be suitable as recipients for supporting donor PGCs by injecting green fluorescent protein-labelled chicken PGCs into 3-day-old Guinea fowl and domestic fowl hybrid embryos and monitoring PGC development. The injected PGCs colonized almost 100% of the recipient gonads and produced mature spermatozoa after 44 weeks. However, gamete production in these hybrids was initiated much slower than in domestic fowls. This delay may be caused by suboptimal hormonal regulation of gametogenesis in the hybrids. Our results suggest that sterile interspecific hybrids may be suitable hosts for PGCs for efficient gamete production.
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Galinhas , Células Germinativas , Espermatozoides , Animais , Masculino , Feminino , Quimera , Proteínas de Fluorescência Verde/metabolismo , Proteínas de Fluorescência Verde/genéticaRESUMO
INTRODUCTION: A sterile technique is a standard to reduce microorganism transmission during surgery. Gaps in knowledge and practice in sterile techniques by nurses are common causes of surgical site infections for surgical patients. Even though surgical site infection is a global problem due to lack of knowledge and practice, almost no study has been done in Ethiopia regarding nurses' knowledge and practice of sterile techniques in the operating room. Therefore, this study aimed to assess nurses' knowledge, practice, and associated factors of sterile techniques in Addis Ababa public hospitals, Ethiopia. METHOD: An institutional-based cross-sectional study was conducted on 423 nurses who were working in sixty-six operation rooms at seven public hospitals in Addis Ababa, Ethiopia, from May 11 to June 26/2022. A simple random sampling method was employed to select study participants. A pre-tested, self-administered questionnaire was used to collect data. Data were entered by Epi-data version 4.6 and analyzed by SPSS version 25. Descriptive statistics were presented by text, table, and figure. Multivariable analysis was used to identify the association between the dependent variable and independent variables. Variables with a P-value < 0.05 were considered statistically significant. RESULT: Nearly three-fifths (58.1%; 95%CI: 53.2 to 63.7) of respondents had good knowledge, and 56.1% with 95%CI (51.5 to 61.1) had good practice with respect to sterile techniques in the operation room. Training [AOR = 1.989; 95%CI (1.120 to 3.530)], availability of guidelines [AOR = 6.4; 95%CI (3.773 to 10.856)], and supervision [AOR = 2.963; 95%CI (1.693 to 5.184)] were associated with nurses' knowledge about sterile techniques in the operating room. Availability of guidelines [AOR = 1.890, 95%CI (1.123 to 3.182)], presence of supervision [AOR = 4.732; 95%CI (2.643 to 8.471)], and having good knowledge of sterile techniques [AOR = 5.419; 95%CI (3.087 to 9.512)] were associated with nurses' practice of sterile techniques in the operation room. CONCLUSION: Operative theater nurses' knowledge and practice of sterile techniques were found inadequate. Training, supervision, availability of guidelines, and knowledge of nurses towards sterile techniques are factors associated with sterile techniques in the operating room. So, it is better to strengthen training, equip wards with standardized guidelines, and provide supervision, which is crucial to enhancing their knowledge and practice.
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Sterile technique is the collective actions taken to reduce potential contaminants in the OR and maintain a sterile field during operative or other invasive procedures. Practicing and applying the principles of sterile technique is a cornerstone of perioperative nursing and providing safe patient care. The recently updated AORN "Guideline for sterile technique" provides perioperative nurses with information on the principles of and processes associated with sterile technique. This article provides an overview of the guideline and discusses recommendations for actions to take before preparing the sterile field, while preparing and maintaining the sterile field, for limiting movement, for surgical wound classification, and for quality. It also includes a scenario describing the implementation of isolation technique (ie, clean closure) for colon procedures. Perioperative nurses should review the guideline in its entirety and apply the recommendations when practicing sterile technique.
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Esterilização , Humanos , Esterilização/normas , Esterilização/métodos , Guias de Prática Clínica como Assunto , Enfermagem Perioperatória/normas , Enfermagem Perioperatória/métodosRESUMO
BACKGROUND: Sperm development and behavior present promising targets for environmentally safer, target-specific biorational control strategies. Serine protease in seminal fluid proteins plays a crucial role in the post-mating reproductive processes of lepidopteran pest insects. The serine protease 2 has been identified as the initiatorin of the seminal fluid protein in Lepidoptera, and its loss of function leads to male sterility. Nevertheless, the genetic pattern of this gene mutation and the impacts of various mutant genotypes on the hatchability of the eggs of pests remain unclear. RESULTS: This study focused on the cloning of Spodoptera exigua serine protease 2 (SeSer2), which is specifically expressed in male moths. The open reading frame of SeSer2 consists of 843 nucleotides, encoding 280 amino acids with structural characteristics typical of serine proteases in the S1 family. To validate the functional role of SeSer2 in the fertility of S. exigua, a targeted ~3574-bp deletion of SeSer2 was introduced using the CRISPR/Cas9 genome editing system, leading to premature truncation of the SeSer2 protein. The SeSer2 mutation had no significant impact on the growth and development of individuals of either sex. However, disruption of SeSer2 resulted in heritable male sterility. Although females mated with SeSer2-/- (SeSer2 knockout homozygote) males laid eggs normally, these eggs failed to hatch. SeSer2+/- (SeSer2 knockout heterozygote) male moths crossed with female moths produced viable offspring, indicating the gene's recessive role in egg hatching. CONCLUSION: These findings strongly support the conclusion that the Ser2 gene is essential for male reproductive success in diverse lepidopterans. Targeting the Ser2 gene holds promise as a foundational element of a novel pest control strategy. © 2024 Society of Chemical Industry.
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Spotted wing Drosophila (Drosophila suzukii Matsumura, or SWD), an insect pest of soft-skinned fruits native to East Asia, has rapidly spread worldwide in the past 15 years. Genetic controls such as sterile insect technique (SIT) have been considered for the environmentally friendly and cost-effective management of this pest. In this review, we provide the latest developments for the genetic control strategies of SWD, including sperm-marking strains, CRISPR-based sex-ratio distortion, neoclassical genetic sexing strains, transgenic sexing strains, a sex-sorting incompatible male system, precision-guided SIT, and gene drives based on synthetic Maternal effect dominant embryonic arrest (Medea) or homing CRISPR systems. These strategies could either enhance the efficacy of traditional SIT or serve as standalone methods for the sustainable control of SWD.
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Background and Aim: Rhodamine-B (Rh-B) marking shows a great potential for use in mark-release-recapture (MRR) studies for rear-and-release mosquito control strategies, including the radiation-based sterile insect technique. However, its applicability and evaluation in body-stain-irradiated males of Aedes aegypti have received little attention. The present study evaluated the use of Rh-B to mark gamma-irradiated male A. aegypti. Materials and Methods: Male A. aegypti were irradiated at the pupal stage at a dose of 70 Gy. After emergence, males were fed 0.1, 0.2, 0.3, or 0.4% Rh-B in 10% glucose solution for 4 days. Groups of unirradiated males that received the same feeding treatments were used as control groups. We evaluated the persistence of Rh-B and the longevity of males after Rh-B feeding. Furthermore, the use of Rh-B in irradiated A. aegypti for MRR experiments was evaluated at an urban site. Results: No difference was observed in the Rh-B persistence among all concentrations at the 24-h postmarking period ranging from 91.25 ± 1.61% to 96.25 ± 1.61% and from 90.00 ± 2.28% to 93.13 ± 2.77% for the unirradiated and irradiated groups, respectively. Rh-B persistence significantly decreased over time, and persistence was significantly longer with increased concentrations in both the unirradiated and irradiated groups. Longevity was considerably decreased by Rh-B feeding and irradiation. However, no significant difference in longevity was found among males fed various concentrations of Rh-B. Through MRR experiments, irradiated-Rh-B marked males were mostly detected within a radius of 20 m and 40 m from the center-release point. The mean distance traveled of the released males from the three MRR events was calculated to be 42.6 m. Conclusion: This study confirms that Rh-B body marking through sugar feeding is applicable for irradiated male A. aegypti, with only a slight effect on longevity. Furthermore, considering the significant reduction in persistence over time, further study is needed to assess the impact of this reduction on the calculation of field biological parameters resulting from MRR experiments.
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The fall armyworm (Spodoptera frugiperda) poses a substantial threat to many important crops worldwide, emphasizing the need to develop and implement advanced technologies for effective pest control. CRISPR/Cas9, derived from the bacterial adaptive immune system, is a prominent tool used for genome editing in living organisms. Due to its high specificity and adaptability, the CRISPR/Cas9 system has been used in various functional gene studies through gene knockout and applied in research to engineer phenotypes that may cause economical losses. The practical application of CRISPR/Cas9 in diverse insect orders has also provided opportunities for developing strategies for genetic pest control, such as gene drive and the precision-guided sterile insect technique (pgSIT). In this review, a comprehensive overview of the recent progress in the application of the CRISPR/Cas9 system for functional gene studies in S. frugiperda is presented. We outline the fundamental principles of applying CRISPR/Cas9 in S. frugiperda through embryonic microinjection and highlight the application of CRISPR/Cas9 in the study of genes associated with diverse biological aspects, including body color, insecticide resistance, olfactory behavior, sex determination, development, and RNAi. The ability of CRISPR/Cas9 technology to induce sterility, disrupt developmental stages, and influence mating behaviors illustrates its comprehensive roles in pest management strategies. Furthermore, this review addresses the limitations of the CRISPR/Cas9 system in studying gene function in S. frugiperda and explores its future potential as a promising tool for controlling this insect pest.
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Sistemas CRISPR-Cas , Edição de Genes , Spodoptera , Sistemas CRISPR-Cas/genética , Edição de Genes/métodos , Animais , Spodoptera/genéticaRESUMO
This study aimed to provide novel information on the impact of indigenous non-Saccharomyces yeasts, including Metschnikowia chrysoperlae, Metschnikowia sinensis/shanxiensis, Metschnikowia pulcherrima, Lachancea thermotolerans, Hanseniaspora uvarum, Hanseniaspora guilliermondii, and Pichia kluyveri, on metabolites related to the metabolism of tryptophan, phenylalanine, and tyrosine. The experiment included two fermentation practices: monoculture and sequential fermentation with commercial Saccharomyces cerevisiae, using sterile Marastina grape juice. A targeted approach through ultrahigh-resolution liquid chromatography associated with mass spectrometry was used to quantify 38 metabolites. All the indigenous yeasts demonstrated better consumption of tryptophan in monoculture than in interaction with S. cerevisiae. M. sinensis/shanxiensis was the only producer of indole-3-carboxylic acid, while its ethyl ester was detected in monoculture fermentation with H. guilliermondii. H. guilliermondii consumed the most phenylalanine among the other isolates. 5-hydroxy-L-tryptophan was detected in fermentations with M. pulcherrima and M. sinensis/shanxiensis. M. pulcherrima significantly increased tryptophol content and utilised tyrosine in monoculture fermentations. Sequential fermentation with M. sinensis/shanxiensis and S. cerevisiae produced higher amounts of N-acetyl derivatives of tryptophan and phenylalanine, while H. guilliermondii-S. cerevisiae fermentation resulted in wines with the highest concentrations of L-kynurenine and 3-hydroxyanthranilic acid. P. kluyveri produced the highest concentration of N-acetyl-L-tyrosine in monoculture fermentations. These findings highlight the different yeast metabolic pathways.
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Aedes albopictus is considered one of the major invasive species in the world and can transmit viruses such as dengue, Zika, or chikungunya. The Sterile Insect Technique (SIT) can be used to suppress the native populations of Ae. albopictus. Mark-release-recapture (MRR) studies are crucial to support the development of the release strategy during the SIT application. Meanwhile, weather conditions can affect the MRR trial's results and it is critical to understand the influence of climatic factors on the results. In October 2022, 84,000 irradiated sterile males were released for three consecutive weeks in Faro, Southern Portugal. Mosquitoes were recaptured by human landing collection (HLC) one, two, four, and six days after release. Generalized linear models with a negative binomial family and log function were used to estimate the factors associated with the number of recaptured mosquitoes, prevalence ratios, and the 95% confidence intervals (CIs). A total of 84,000 sterile male mosquitoes were released, with 528 recaptured (0.8%) by HLC. The prevalence of recaptured mosquitoes was 23% lower when the wind intensity was moderate. Marked sterile males had an average median distance travelled of 88.7 m. The median probability of daily survival and the average life expectancy were 61.6% and 2.1 days, respectively. The wild male population estimate was 443.33 males/ha. Despite no statistically significant association being found with humidity, temperature, and precipitation, it is important to consider weather conditions during MRR trial analyses to obtain the best determinant estimation and a more efficient application of the SIT in an integrated vector management program.
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The key to success in the application of the sterile insect technique (SIT) relies on the ability of released, sterile males to outcompete their fertile wild male counterparts to mate with wild females. However, many insect species exhibit multiple-mating behavior, which can be a way for females to select paternity for their progeny. This study aims to recognize the consequences of potential double-matings during an SIT program and to detect any evidence of sperm selection favoring sperm from fertile mates. This report provides a descriptive analysis of the storage and use of sperm by female Aedes albopictus. Stable isotopes were used to mark the sperm of fertile and sterile males. Mated females were allowed to oviposit before dissecting the spermathecae to link the presence of each type of sperm to the sterility of the eggs laid. It was found that sperm in females inseminated by both males was distributed in the three spermathecae with no obvious pattern, mostly mixed but also separately, and no evidence of any mechanism for sperm selection, sperm precedence, or sperm competition in Ae. albopictus females could be found. The fact that only a few double-mated females were double-inseminated and could also produce semi-sterile eggs, together with the finding that the sperm of sterile males appeared to be no less viable than that of fertile males, is an encouraging outcome for SIT approaches.
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Sterile inflammation is involved in the lung pathogenesis induced by respirable particles, including micro- and nanoplastics. Their increasing amounts in the ambient and in indoor air pose a risk to human health. In two human cell lines (A549 and THP-1) we assessed the proinflammatory behavior of polystyrene nanoplastics (nPS) and microplastics (mPS) (Ø 0.1 and 1 µm). Reproducing environmental aging, in addition to virgin, the cells were exposed to oxidized nPS/mPS. To study the response of the monocytes to the inflammatory signal transmitted by the A549 through the release of soluble factors (e.g. alarmins and cytokines), THP-1 cells were also exposed to the supernatants of previously nPS/mPS-treated A549. After dynamic-light-scattering (DLS) analysis and protein measurements for the assessment of protein corona in nPS/mPS, real-time PCR and enzyme-linked-immunosorbent (ELISA) assays were performed in exposed cells. The pro-inflammatory effects of v- and ox-nPS/mPS were attested by the imbalance of the Bax/Bcl-2 ratio in A549, which was able to trigger the inflammatory cascade, inhibiting the immunologically silent apoptosis. The involvement of NFkB was confirmed by the overexpression of p65 after exposure to ox-nPS and v- and ox-mPS. The fast and higher levels of IL-1ß, only in THP-1 cells, underlined the NLPR3 inflammasome activation.