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BACKGROUND: Around 30% of nonexudative macular neovascularizations exudate within 2 years from diagnosis in patients with age-related macular degeneration. The aim of this study is to develop a deep learning classifier based on optical coherence tomography (OCT) and OCT angiography (OCTA) to identify nonexudative macular neovascularizations at risk of exudation. METHODS: Patients with age-related macular degeneration showing OCTA and fluorescein angiography-documented nonexudative macular neovascularization with a 2-year minimum imaging follow-up were retrospectively selected. Patients showing OCT B-scan-documented macular neovascularization exudation within the first 2 years formed the EX GROUP while the others formed the QU GROUP. ResNet-101, Inception-ResNet-v2, and DenseNet-201 were independently trained on OCTA and OCT B-scan images. Combinations of the six models were evaluated with major and soft voting techniques. RESULTS: Eighty-nine eyes of 89 patients with a follow-up of 5.7 ± 1.5 years were recruited (35 EX GROUP and 54 QU GROUP). Inception-ResNet-v2 was the best performing among the three single convolutional neural networks. The major voting model resulting from the association of the three different convolutional neural networks resulted in an improvement of performance both for OCTA and OCT B-scan (both significantly higher than human graders' performance). The soft voting model resulting from the combination of OCTA and OCT B-scan-based major voting models showed a testing accuracy of 94.4%. Peripheral arcades and large vessels on OCTA en face imaging were more prevalent in the QU GROUP. CONCLUSION: Artificial intelligence shows high performances in identifications of nonexudative macular neovascularizations at risk for exudation within the first 2 years of follow-up, allowing better customization of follow-up timing and avoiding treatment delay. Better results are obtained with the combination of OCTA and OCT B-scan image analysis.
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Aprendizado Profundo , Angiofluoresceinografia , Tomografia de Coerência Óptica , Humanos , Tomografia de Coerência Óptica/métodos , Estudos Retrospectivos , Masculino , Feminino , Angiofluoresceinografia/métodos , Idoso , Seguimentos , Idoso de 80 Anos ou mais , Degeneração Macular Exsudativa/diagnóstico , Degeneração Macular Exsudativa/tratamento farmacológico , Fundo de Olho , Acuidade Visual , Macula Lutea/diagnóstico por imagem , Macula Lutea/patologia , Neovascularização Retiniana/diagnóstico , Neovascularização Retiniana/etiologiaRESUMO
PURPOSE: To predict improvement of best-corrected visual acuity (BCVA) 1 year after pars plana vitrectomy for epiretinal membrane (ERM) using artificial intelligence methods on optical coherence tomography B-scan images. METHODS: Four hundred and eleven (411) patients with Stage II ERM were divided in a group improvement (IM) (≥15 ETDRS letters of VA recovery) and a group no improvement (N-IM) (<15 letters) according to 1-year VA improvement after 25-G pars plana vitrectomy with internal limiting membrane peeling. Primary outcome was the creation of a deep learning classifier (DLC) based on optical coherence tomography B-scan images for prediction. Secondary outcome was assessment of the influence of various clinical and imaging predictors on BCVA improvement. Inception-ResNet-V2 was trained using standard augmentation techniques. Testing was performed on an external data set. For secondary outcome, B-scan acquisitions were analyzed by graders both before and after fibrillary change processing enhancement. RESULTS: The overall performance of the DLC showed a sensitivity of 87.3% and a specificity of 86.2%. Regression analysis showed a difference in preoperative images prevalence of ectopic inner foveal layer, foveal detachment, ellipsoid zone interruption, cotton wool sign, unprocessed fibrillary changes (odds ratio = 2.75 [confidence interval: 2.49-2.96]), and processed fibrillary changes (odds ratio = 5.42 [confidence interval: 4.81-6.08]), whereas preoperative BCVA and central macular thickness did not differ between groups. CONCLUSION: The DLC showed high performances in predicting 1-year visual outcome in ERM surgery patients. Fibrillary changes should also be considered as relevant predictors.
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Membrana Epirretiniana , Humanos , Membrana Epirretiniana/diagnóstico , Membrana Epirretiniana/cirurgia , Inteligência Artificial , Estudos Retrospectivos , Acuidade Visual , Retina , Tomografia de Coerência Óptica/métodos , Vitrectomia/métodosRESUMO
When assessing trainees' progresses during a driving training program, instructors can only rely on the evaluation of a trainee's explicit behavior and their performance, without having any insight about the training effects at a cognitive level. However, being able to drive does not imply knowing how to drive safely in a complex scenario such as the road traffic. Indeed, the latter point involves mental aspects, such as the ability to manage and allocate one's mental effort appropriately, which are difficult to assess objectively. In this scenario, this study investigates the validity of deploying an electroencephalographic neurometric of mental effort, obtained through a wearable electroencephalographic device, to improve the assessment of the trainee. The study engaged 22 young people, without or with limited driving experience. They were asked to drive along five different but similar urban routes, while their brain activity was recorded through electroencephalography. Moreover, driving performance, subjective and reaction times measures were collected for a multimodal analysis. In terms of subjective and performance measures, no driving improvement could be detected either through the driver's subjective measures or through their driving performance. On the other side, through the electroencephalographic neurometric of mental effort, it was possible to catch their improvement in terms of mental performance, with a decrease in experienced mental demand after three repetitions of the driving training tasks. These results were confirmed by the analysis of reaction times, that significantly improved from the third repetition as well. Therefore, being able to measure when a task is less mentally demanding, and so more automatic, allows to deduce the degree of users training, becoming capable of handling additional tasks and reacting to unexpected events.
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Condução de Veículo , Dispositivos Eletrônicos Vestíveis , Humanos , Adolescente , Tempo de Reação , Eletroencefalografia/métodos , Acidentes de TrânsitoRESUMO
Pseudomonas aeruginosa is an opportunistic pathogen associated with severe diseases, such as cystic fibrosis. During an extensive search for novel essential genes, we identified tgpA (locus PA2873) in P. aeruginosa PAO1, as a gene playing a critical role in bacterial viability. TgpA, the translated protein, is an internal membrane protein with a periplasmic soluble domain, predicted to be endowed with a transglutaminase-like fold, hosting the Cys404, His448, and Asp464 triad. We report here that Cys404 mutation hampers the essential role of TgpA in granting P. aeruginosa viability. Moreover, we present the crystal structure of the TgpA periplasmic domain at 1.6â¯Å resolution as a first step towards structure-activity analysis of a new potential target for the discovery of antibacterial compounds.
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Proteínas de Bactérias/química , Proteínas de Membrana/química , Peptidoglicano/química , Periplasma/química , Pseudomonas aeruginosa/química , Motivos de Aminoácidos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Domínio Catalítico , Clonagem Molecular , Cristalografia por Raios X , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Viabilidade Microbiana , Modelos Moleculares , Mutação , Peptidoglicano/metabolismo , Periplasma/enzimologia , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Pseudomonas aeruginosa/enzimologia , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Especificidade por SubstratoRESUMO
The small RNA ReaL of the opportunistic pathogen Pseudomonas aeruginosa has been characterized. Our results indicate that ReaL contributes to P. aeruginosa virulence. In the Galleria mellonella infection model, reaL gene deletion resulted in decreased virulence, while ReaL overexpression resulted in a hyper-virulent phenotype. We also demonstrate that ReaL is embedded in the P. aeruginosa quorum sensing (QS) with the role of linking las to pqs systems. We show that ReaL is negatively regulated by the las regulator LasR and impacts positively the synthesis of the pqs quinolone signal PQS by a positive post-transcriptional effect on the pqsC gene. Perturbations of ReaL levels affect pyocyanin synthesis, biofilm formation and swarming motility, processes that are known to be influenced by PQS synthesis. In addition to being regulated by LasR, ReaL is also responding to infection relevant cues that P. aeruginosa can experience in mammalian hosts such as temperature and oxygen availability. Furthermore, ReaL shows a growth phase-dependent pattern of expression, being up-regulated in stationary phase, due to the activity of the alternative σ factor RpoS. Together, these regulations of ReaL expression are expected to contribute to the fine co-modulation of PQS synthesis and, ultimately, virulence.
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Regulação Bacteriana da Expressão Gênica/genética , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/patogenicidade , Percepção de Quorum/genética , RNA Nuclear Pequeno/genética , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Deleção de Genes , Mariposas/microbiologia , Infecções por Pseudomonas/microbiologia , Infecções por Pseudomonas/patologia , Piocianina/metabolismo , Quinolonas/metabolismo , Fator sigma/metabolismo , Transdução de Sinais/genética , Transativadores/genética , VirulênciaRESUMO
The Pseudomonas aeruginosa PA3685 locus encodes a conserved protein that shares 49% sequence identity with Escherichia coli YeaZ, which was recently reported as involved in the biosynthesis of threonylcarbamoyl adenosine (t(6)A), a universal modified tRNA nucleoside. Many YeaZ orthologues were reported as "essential for life" among various bacterial species, suggesting a critical role for both these proteins and for the t(6)A biosynthetic pathway. We provide here evidences that PA3685 protein (PaYeaZ) is essential. Additionally, we describe its purification, crystallization, and crystallographic structure. The crystal structure shows that PaYeaZ is composed of two domains one of which is the platform to form protein-protein interaction involved either in homodimeric assembly or in the formation of the multiprotein complex required for the synthesis of t(6)A. These features make the PaYeaZ protein a potential target candidate for the design of novel inhibitors able to hinder the complex formation and expected to abolish the crucial activity of t(6)A synthesis.
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Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/ultraestrutura , Pseudomonas aeruginosa/fisiologia , Sequência de Aminoácidos , Sítios de Ligação , Sobrevivência Celular/fisiologia , Cristalografia , Proteínas de Escherichia coli/química , Dados de Sequência Molecular , Ligação Proteica , Conformação Proteica , Estrutura Terciária de Proteína , Pseudomonas aeruginosa/citologia , Relação Estrutura-AtividadeRESUMO
Modulation of mRNA translatability either by trans-acting factors (proteins or sRNAs) or by in cis-acting riboregulators is widespread in bacteria and controls relevant phenotypic traits. Unfortunately, global identification of post-transcriptionally regulated genes is complicated by poor structural and functional conservation of regulatory elements and by the limitations of proteomic approaches in protein quantification. We devised a genetic system for the identification of post-transcriptionally regulated genes and we applied this system to search for Pseudomonas aeruginosa RNA thermometers, a class of regulatory RNA that modulates gene translation in response to temperature changes. As P. aeruginosa is able to thrive in a broad range of environmental conditions, genes differentially expressed at 37 °C versus lower temperatures may be involved in infection and survival in the human host. We prepared a plasmid vector library with translational fusions of P. aeruginosa DNA fragments (PaDNA) inserted upstream of TIP2, a short peptide able to inactivate the Tet repressor (TetR) upon expression. The library was assayed in a streptomycin-resistant merodiploid rpsL(+)/rpsL31 Escherichia coli strain in which the dominant rpsL(+) allele, which confers streptomycin sensitivity, was repressed by TetR. PaDNA fragments conferring thermosensitive streptomycin resistance (i.e., expressing PaDNA-TIP2 fusions at 37°C, but not at 28°C) were sequenced. We identified four new putative thermosensors. Two of them were validated with conventional reporter systems in E. coli and P. aeruginosa. Interestingly, one regulates the expression of ptxS, a gene implicated in P. aeruginosa pathogenesis.
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Proteínas de Bactérias/genética , Proteínas de Ligação a DNA/genética , Proteínas de Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica , Fosfotransferases (Aceptor do Grupo Fosfato)/genética , RNA Bacteriano/biossíntese , RNA Mensageiro/biossíntese , Fatores de Transcrição/genética , Escherichia coli/genética , Resposta ao Choque Térmico/genética , Humanos , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/crescimento & desenvolvimento , RNA Bacteriano/genética , RNA Mensageiro/genética , Proteína S9 Ribossômica , TemperaturaRESUMO
The small RNA ErsA of Pseudomonas aeruginosa, transcribed from the same genomic context of the well-known Escherichia coliâ Spot 42, has been characterized. We show that, different from Spot 42, ErsA is under the transcriptional control of the envelope stress response, which is known to impact the pathogenesis of P. aeruginosa through the activity of the alternative sigma factor σ(22) . The transcriptional responsiveness of ErsA RNA also spans infection-relevant cues that P. aeruginosa can experience in mammalian hosts, such as limited iron availability, temperature shifts from environmental to body temperature and reduced oxygen conditions. Another difference between Spot 42 and ErsA is that ErsA does not seem to be involved in the regulation of carbon source catabolism. Instead, our results suggest that ErsA is linked to anabolic functions for the synthesis of exoproducts from sugar precursors. We show that ErsA directly operates in the negative post-transcriptional regulation of the algC gene that encodes the virulence-associated enzyme AlgC, which provides sugar precursors for the synthesis of several P. aeruginosa polysaccharides. Like ErsA, the activation of algC expression is also dependent on σ(22) . Altogether, our results suggest that ErsA and σ(22) combine in an incoherent feed-forward loop to fine-tune AlgC enzyme expression.
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Regulação Bacteriana da Expressão Gênica , Fosfoglucomutase/genética , Fosfotransferases (Fosfomutases)/genética , Pseudomonas aeruginosa/genética , Pequeno RNA não Traduzido/metabolismo , Regulação Enzimológica da Expressão Gênica , Fosfoglucomutase/metabolismo , Fosfotransferases (Fosfomutases)/metabolismo , Pseudomonas aeruginosa/metabolismo , Pseudomonas aeruginosa/patogenicidade , Pequeno RNA não Traduzido/química , Pequeno RNA não Traduzido/genética , Regulon , Fator sigma/metabolismo , Fatores de Virulência/genéticaRESUMO
PURPOSE: Radial keratotomies (RKs) are responsible for corneal irregularities resulting in biometric errors and lower best-corrected visual acuity (BCVA) due to lower-order and higher-order optical aberrations. The aim of the study was to compare performances of new and old generation formulas in a population of RK patients. METHODS: RK patients who underwent phacoemulsification with intraocular lens (IOL) implantation were retrospectively recruited. Inclusion criteria were availability of preoperative and 6-month postoperative BCVA assessment, topography, and tomography. Documented refraction instability, corneal ectasia, and previous ocular surgery except for RK were exclusion criteria. Mean prediction error (ME), mean absolute prediction error (MAE), and incidence of MAE > 0.25D were calculated for SRK-T, Barrett True K, EVO 2.0, Kane, and PEARL-DGS. RESULTS: Twenty-seven patients with a mean baseline BCVA of 0.32 ± 0.18 logMAR and a mean corneal root mean square (RMS) value of 1.59 ± 0.91 µm were included. EVO 2.0, Kane, and PEARL-DGS showed a significantly lower MAE and lower ME compared with all other formulas ( P < 0.001 and P < 0.001) and a significant lower incidence of MAE >0.25D ( P < 0.001). Significant differences were still detected when using 3-mm mean keratometry for IOL calculation. CONCLUSIONS: PEARL-DGS, Kane, and EVO 2.0 formulas show superior accuracy in IOL power calculation compared with SRK-T and Barrett True K in RK patients, with no significant differences between the 3.
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Ceratotomia Radial , Lentes Intraoculares , Facoemulsificação , Humanos , Acuidade Visual , Estudos Retrospectivos , Refração Ocular , Facoemulsificação/métodos , Biometria/métodos , Óptica e FotônicaRESUMO
PURPOSE: This case report describes an innovative procedure for addressing retinal detachment in patients with morning glory syndrome. METHODS: An 18-year-old woman with unilateral morning glory syndrome complicated by macula-off retinal detachment without any visible peripheral retinal breaks underwent three corrective surgeries. In the first surgery, a 25-gauge pars plana vitrectomy with a 3-mm human amniotic membrane patch positioned on the optic disc and gas endotamponade was performed. When the gas reabsorbed, inferior retinal detachment recurred, and a second vitrectomy with silicone oil endotamponade was conducted. At three months, the retina was still attached under the silicone oil, so the oil was removed. At the second follow-up, retinal detachment had recurred, and a third vitrectomy with a larger amniotic patch and silicone oil endotamponade was performed. RESULTS: Three months following the last surgery, the subretinal fluid had totally reabsorbed, and the retina was completely attached. The best-corrected visual acuity was 20/100. CONCLUSION: To the best of our knowledge, the first description of a human amniotic patch associated with vitrectomy in morning glory syndrome complicated with retinal detachment is described. Using human amniotic membranes, positioned onto the optic nerve, and silicone oil endotamponade could be useful for morning glory syndrome complicated by retinal detachment.
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Descolamento Retiniano , Feminino , Humanos , Adolescente , Descolamento Retiniano/diagnóstico , Descolamento Retiniano/etiologia , Descolamento Retiniano/cirurgia , Âmnio , Óleos de Silicone , Acuidade Visual , Retina , Vitrectomia/métodos , Síndrome , Recidiva , Estudos RetrospectivosRESUMO
PURPOSE: To analyze differences in refractive outcome Δ (difference between postoperative and expected refractive error) and in anterior segment changes between cataract surgery patients and combined phacovitrectomy patients. We also aimed to provide a corrective formula allowing to minimise the refractive outcome Δ in combined surgery patients. METHODS: Candidates for phacoemulsification and combined phacovitrectomy (respectively PHACO and COMBINED groups) were prospectively enrolled in two specialised centres. Patients underwent best corrected visual acuity (BCVA) assessment, ultra-high speed anterior segment optical coherence tomography (OCT), gonioscopy, retinal OCT, slit lamp examination and biometry at baseline, 6 weeks postoperatively and 3 months postoperatively. RESULTS: No differences in refractive Δ, refractive error and anterior segment parameters were noted between PHACO and COMBINED group (109 and 110 patients respectively) at 6 weeks. At 3 months, COMBINED group showed a spherical equivalent of -0.29 ± 0.10 D versus -0.03 ± 0.15 D in PHACO group (p = 0.023). COMBINED group showed a significantly higher Crystalline Lens Rise (CLR), angle-to-angle (ATA) and anterior chamber width (ACW) and a significantly lower anterior chamber depth (ACD) and refractive Δ with all 4 considered formulas at 3 months. For IOL power lower than 15, a hyperopic shift was observed instead. CONCLUSIONS: Anterior segment OCT suggests anterior displacement of the effective lens position in patients undergoing phacovitrectomy. A corrective formula can be applied to IOL power calculation to minimize undesired refractive error.
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Extração de Catarata , Lentes Intraoculares , Facoemulsificação , Erros de Refração , Humanos , Implante de Lente Intraocular , Refração Ocular , Extração de Catarata/métodos , Facoemulsificação/métodos , Biometria/métodos , Estudos RetrospectivosRESUMO
Placing the origin of an undeciphered script in time is crucial to understanding the invention of writing in human history. Rapa Nui, also known as Easter Island, developed a script, now engraved on fewer than 30 wooden objects, which is still undeciphered. Its origins are also obscure. Central to this issue is whether the script was invented before European travelers reached the island in the eighteenth century AD. Hence direct radiocarbon dating of the wood plays a fundamental role. Until now, only two tablets were directly dated, placing them in the nineteenth c. AD, which does not solve the question of independent invention. Here we radiocarbon-dated four Rongorongo tablets preserved in Rome, Italy. One specimen yielded a unique and secure mid-fifteenth c. date, while the others fall within the nineteenth c. AD. Our results suggest that the use of the script could be placed to a horizon that predates the arrival of external influence.
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Invenções , Madeira , Humanos , Polinésia , Redação , ItáliaRESUMO
Purpose: To evaluate the safety of subretinal injection of cord blood platelet-rich plasma (CB-PRP) and its possible effect in eyes affected by geographic atrophy (GA) associated with dry age-related macular degeneration (d-AMD). Design: Interventional, open-label study started in January 2021 with follow-up at 12 months (the Si.Cord Study). This study was a single-center, nonrandomized, sequential-assigned clinical trial conducted in Rome, Italy, at Fondazione Policlinico Universitario Agostino Gemelli IRCCS (ClinicalTrials.gov NCT04636853). Participants: Thirteen patients (26 eyes) with bilateral d-AMD-related GA were enrolled. One eye from each patient (with more advanced GA) underwent CB-PRP treatment, and the fellow eye was considered the control. All patients participated in follow-up at 12 months. Intervention: All 13 eyes received 23-gauge (G) vitrectomy and subretinal injection of CB-PRP using a 41-gauge needle. Main Outcomes and Measures: Best-corrected visual acuity (BCVA) with ETDRS letters, central macular thickness using OCT, and atrophic area measured on en face OCT images were assessed at baseline, 1, 3, 6, and 12 months. Results: The BCVA in the treated group was 34.46 ± 20.8 ETDRS at baseline, 40.84 ± 20.52 at 1 month, 40.07 ± 20.34 at 3 months, 39.38 ± 19.84 at 6 months, and 35.84 ± 18.38 at 12 months. In the untreated group, the BCVA was 53 ± 21.1 ETDRS letters at baseline, 51.54 ± 20.99 at 1 month, 46.62 ± 19.47 at 3 months, 46.85 ± 18.58 at 6 months, and 43.92 ± 17.97 at 12 months (2-way analysis of variance: interaction of treatment by eye or time, P = 0.084). Central macular thickness did not show a significant intereye difference at 12 months (P = 0.97). The atrophic geographic areas tended to increase in both treated and fellow eyes at 12 months (P < 0.0001). No inflammatory reaction, endophthalmitis, retinal detachment, uveitis, or other complications due to the subretinal injection of CB-PRP were observed during the follow-up. Conclusions: Subretinal injection of CB-PRP could be safely used for d-AMD in its GA form. Despite its safety, a larger cohort of patients, and probably a new way of administration, will be needed to understand whether the CB-PRP could have a role in the GA treatment. Financial Disclosures: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.
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Hundreds of different species of small RNAs can populate a bacterial cell. This small transcriptome contains important information for the adaptation of cellular physiology to environmental changes. Underlying cellular networks involving small RNAs are RNA-RNA and RNA-protein interactions, which are often intertwined. In addition, small RNAs can function as mRNAs. In general, small RNAs are referred to as noncoding because very few are known to contain translated open reading frames. In this article, we intend to highlight that the number of small RNAs that fall within the set of translated RNAs is bound to increase. In addition, we aim to emphasize that the dynamics of the small transcriptome involve different functional codes, not just the genetic code. Therefore, since the role of small RNAs is always code-driven, we believe that there is little reason to continue calling them small noncoding RNAs.
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Behind the pathogenic lifestyle of Pseudomonas aeruginosa exists a complex regulatory network of intertwined switches at both the transcriptional and posttranscriptional levels. Major players that mediate translation regulation of several genes involved in host-P. aeruginosa interaction are small RNAs (sRNAs) and the Hfq protein. The canonical role of Hfq in sRNA-driven regulation is to act as a matchmaker between sRNAs and target mRNAs. Besides, the sRNA CrcZ is known to sequester Hfq and abrogate its function of translation repression of target mRNAs. In this study, we describe the novel sRNA GssA in the strain PA14 and its multifaceted interplay with Hfq. We show that GssA is multiresponsive to environmental and physiological signals and acts as an apical repressor of key bacterial functions in the human host such as the production of pyocyanin, utilization of glucose, and secretion of exotoxin A. We suggest that the main role of Hfq is not to directly assist GssA in its regulatory role but to repress GssA expression. In the case of pyocyanin production, we suggest that Hfq interplays with GssA also by converging a positive effect on this pathway. Furthermore, our results indicate that both Hfq and GssA play a positive role in anaerobic growth, possibly by regulating the respiratory chain. On the other hand, we show that GssA can modulate not only Hfq expression at both transcriptional and posttranscriptional levels but also that of CrcZ, thus potentially influencing the pleiotropic role of Hfq. IMPORTANCE The pathogenic lifestyle of the bacterium Pseudomonas aeruginosa, a leading cause of life-threatening infections in the airways of cystic fibrosis patients, is based on the fine regulation of virulence-associated factors. Regulatory small RNAs (sRNAs) and the RNA-binding protein Hfq are recognized key components within the P. aeruginosa regulatory networks involved in host-pathogen interaction. In this study, we characterized in the highly virulent P. aeruginosa strain PA14 the novel sRNA GssA. We found that it can establish a many-sided reciprocal interplay with Hfq which goes beyond the canonical mechanism of direct physical interaction that had previously been characterized for other sRNAs. Given that the Hfq-driven regulatory network of virulence factors is very broad and important for the progression of infection, we consider GssA as a new RNA target that can potentially be used to develop new antibacterial drugs.
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Pseudomonas aeruginosa , Pequeno RNA não Traduzido , Humanos , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , RNA Bacteriano/genética , RNA Bacteriano/metabolismo , Piocianina , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , RNA Mensageiro/genética , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Pequeno RNA não Traduzido/genética , Pequeno RNA não Traduzido/metabolismo , Regulação Bacteriana da Expressão Gênica , Fator Proteico 1 do Hospedeiro/genética , Fator Proteico 1 do Hospedeiro/metabolismoRESUMO
Purpose: Geometric perfusion deficit (GPD) is a newly described OCT angiography (OCTA) parameter identifying the total area of presumed retinal ischemia. The aim of our study is to characterize differences in GPD and other common quantitative OCTA parameters between macular full field, perivenular zones, and periarteriolar zones for each clinical stage of nonproliferative diabetic retinopathy (DR) and to assess the influence of ultrahigh-speed acquisition and averaging on the described differences. Design: Prospective observational study. Participants: Forty-nine patients, including 11 (22.4%) with no sign of DR, 12 (24.5%) with mild DR, 13 (26.5%) with moderate DR, and 13 (26.5%) with severe DR. Patients with diabetic macular edema, proliferative DR, media opacity, head tremor, and overlapping retinal diseases or systemic diseases influencing OCTA were excluded. Methods: OCT angiography was performed 3 times for each patient: 1 using Solix Fullrange single volume (V1) mode, 1 using Solix Fullrange 4 volumes mode with automatically averaged scan (V4), and 1 using AngioVue. Main Outcome Measures: Full macular, periarteriolar, and perivenular perfusion density (PD), vessel length density (VLD), vessel density index, and GPD for both the superficial capillary plexus (SCP) and deep capillary plexus (DCP). Results: In patients showing no sign of DR, PD and VLD were significantly lower in the perivenular area in both the DCP and SCP using V1 and V4, whereas GPD was significantly higher in the perivenular zone in the DCP and SCP with all 3 devices. In patients with mild DR, all 3 measurements (PD, VLD, and GPD) were significantly different in the perivenular zone with all 3 devices. In patients with moderate DR, PD and VLD were lower in the DCP and SCP when measured with V1 and V4. Moreover, GPD was higher in the perivenular zone in the DCP with all 3 devices, whereas only V4 detected a difference in the SCP. In severe DR, only V4 detected a lower PD and VLD and a higher GPD in the DCP of the perivenular zone. V4 also detected a higher GPD in the SCP. Conclusions: Geometric perfusion deficit highlights prevalent perivenular location of macular capillary ischemia in all stages of DR. In severe DR patients, only averaging technology allows detection of the same finding. Financial Disclosures: The author(s) have no proprietary or commercial interest in any materials discussed in this article.
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OBJECTIVES: To investigate the correlation between the AI-measured area of the lacquer cracks (LC) at their first detection and the occurrence of a choroidal neovascularization (CNV) during the follow-up in patients affected by pathologic myopia. Secondary outcome was the detection of a correlation between the time to onset of CNV with both baseline LC area and LC area increase during follow-up. METHODS: Optical coherence tomography (OCT) acquisitions of patients diagnosed with LC were retrospectively analysed. The study population was divided in a CNV group (showing the documented onset of a CNV) and a n-CNV group (no CNV development during follow-up). LC area was measured using MatLab software after the application of a customized method for LC segmentation on infrared (IR) enface images. RESULTS: Forty-five (45) patients with a mean follow-up of 4.9 ± 1.5 years were included. LC area at baseline was 2.82 ± 0.54 mm2 and 1.70 ± 0.49 mm2 in CNV (20 patients) and n-CNV group (25 patients) group respectively (p < 0.001). LC area increase was significantly higher in CNV group (p < 0.001). Time to onset of CNV was linearly correlated with both LC area at baseline (p = 0.006) and LC area increase (p < 0.001). CONCLUSIONS: Myopic CNV development is associated with lager LC areas and higher LC area increase during time. Earlier CNV onset is inversely correlated with LC area and LC area increase.
Assuntos
Neovascularização de Coroide , Miopia Degenerativa , Humanos , Estudos Retrospectivos , Laca , Neovascularização de Coroide/diagnóstico , Neovascularização de Coroide/complicações , Tomografia de Coerência Óptica , Angiofluoresceinografia/métodos , Miopia Degenerativa/complicações , Miopia Degenerativa/diagnósticoRESUMO
It has been demonstrated that odors could affect humans at the psychophysiological level. Significant research has been done on odor perception and physiological mechanisms; however, this research was mainly performed in highly controlled conditions in order to highlight the perceptive phenomena and the correlated physiological responses in the time frame of milliseconds. The present study explored how human physiological activity evolves in response to different odor conditions during an ecological olfactory experience on a broader time scale (from 1 to 90 s). Two odors, vanilla and menthol, together with a control condition (blank) were employed as stimuli. Electroencephalographic (EEG) activity in four frequency bands of interest, theta, alpha, low beta, and high beta, and the electrodermal activity (EDA) of the skin conductance level and response (SCL and SCR) were investigated at five time points taken during: (i) the first ten seconds of exposure (short-term analysis) and (ii) throughout the entire exposure to each odor (90 s, long-term analysis). The results revealed significant interactions between the odor conditions and the time periods in the short-term analysis for the overall frontal activity in the theta (p = 0.03), alpha (p = 0.005), and low beta (p = 0.0067) bands, the frontal midline activity in the alpha (p = 0.015) and low beta (p = 0.02) bands, and the SCR component (p = 0.024). For the long-term effects, instead, only one EEG parameter, frontal alpha asymmetry, was significantly sensitive to the considered dimensions (p = 0.037). In conclusion, the present research determined the physiological response to different odor conditions, also demonstrating the sensitivity of the employed parameters in characterizing the dynamic of such response during the time. As an exploratory study, this work points out the relevance of considering the effects of continuous exposure instead of short stimulation when evaluating the human olfactory experience, providing insights for future studies in the field.
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Not all elements displayed in a YouTube in-stream video ad are attributable to the ad itself. Some of those are automatically introduced by the platform, such as the countdown timer and the time progress bar. In recent years, some authors started exploring the effects associated with the presence of such non-ad items, providing valuable findings. However, objective evaluation of viewers' visual attention is lacking in this context as well as emotional investigation. In addition, previous research showed how the manipulation of seemingly negligible details can yield dramatically different outcomes in the context of in-stream advertising. To extend knowledge, the authors explored the effects of the non-ad items' presence by employing eye-tracking and facial coding techniques in combination with self-reports in a between-subjects experimental design focusing on the YouTube 15-s, mid-roll, non-skippable in-stream ad format. Results showed that the ad format currently employed by YouTube performs worse than its equivalent without the non-ad items on all the investigated measures and than its equivalent in which the non-ad items' presence was experimentally reduced on facial coding disgust, self-reported disgust, ad irritation, and ad attitude. Managerial insights and challenges concerning the future of in-stream advertising and neuromarketing are highlighted.
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PURPOSE: To evaluate three months follow-up of SING IMT implant in patients affected by late-stage AMD. DESIGN: Prospective cohort study. SUBJECTS: In a total of 80 eyes of 40 patients who underwent the enrollment tests, 11 patients' eyes affected by late-stage AMD matched the inclusion criteria and underwent SING IMT implant from February to June 2022. METHODS: Before surgery, each patient underwent the enrollment examination to verify inclusion and exclusion criteria. MAIN OUTCOME MEASURES: BCVA for distance and for near, IOP, ACD and ECD were evaluated at 1 and 3 months follow up. Also quality of life in doing the activities of daily life was evaluated. RESULTS: BCVA for distance and for near improved from baseline to 3 months follow up (23.91 ± 9.418 ETDRS letters and 59.09 ± 11.58 ETDRS letters respectively (p < 0.001). An endothelial cell loss was shown (p < 0.001), with a rate of cell density reduction around 8.3% (baseline vs 3 months). CONCLUSIONS: SING IMT could be a valid surgical device to improve patients' sight and quality of life which have been deteriorated by late-stage macular degeneration. Further studies with more patients and longer follow up are needed to confirm our results.