Long-term effectiveness and safety of XEN45 in open-angle glaucoma patients.

BACKGROUND: To investigate the long-term effectiveness and safety of XEN45 implant, either alone or in combination with phacoemulsification, in eyes with open-angle glaucoma (OAG). METHODS: Retrospective and single center study conducted on consecutive OAG patients who underwent a XEN45 implant between February-2017 and December-2021. The primary endpoint was the mean intraocular pressure (IOP) lowering from preoperative values. Surgical success was defined as an IOP-lowering from preoperative values ≥ 20% and an IOP absolute value between 6 and 13 mm Hg, without (Complete-success) or with (Qualified-success) antiglaucoma medications. RESULTS: A total of 158 eyes (34 (21.5%) eyes XEN-solo and 124 (78.5%) XEN + Phaco) were included. The median follow-up time was 28.5 months. In the overall study population, the mean preoperative IOP was significantly lowered from 19.4 ± 6.5 mm Hg to 12.4 ± 5.0 mm Hg. The mean preoperative (95% confidence interval) IOP was significantly lowered from 21.3 (19.3-23.2) mm Hg and 18.8 (17.7-20.0) mm Hg to 12.0 (10.4-13.6) mm Hg and 12.5 (11.6-13.5) mm Hg in the XEN-Solo and XEN + Phaco groups, respectively (p < 0.0001 each, respectively). The mean number of ocular-hypotensive medications was significantly reduced in the overall study sample (from 3.4 ± 0.9 to 0.9 ± 1.3, p < 0.0001), XEN-Solo (from 3.5 ± 1.1 to 0.6 ± 1.0, p < 0.0001, and XEN + Phaco (from 3.4 ± 1.1 to 0.9 ± 1.3, p < 0.0001) groups. Eighty-four (53.2%) eyes were categorized as success, with 49 (58.3%) classified as complete success. Eighty-one (51.3%) eyes underwent needling and 15 (9.5%) eyes required an additional surgical procedure. One (0.6%) eye had endophthalmitis. CONCLUSION: XEN implant, either alone or in combination with phacoemulsification significantly lowered IOP and reduced the need of ocular-hypotensive medication, while maintaining a good safety profile.

Synthesis of Secondary Amines via Self-Limiting Alkylation.

N-centered nucleophilicity increases upon alkylation, and thus selective partial alkylation of ammonia and primary amines can be challenging: Poor selectivity and overalkylation are often observed. Here we introduce N-aminopyridinium salts as ammonia surrogates for the synthesis of secondary amines via self-limiting alkylation chemistry. Readily available N-aryl-N-aminopyridinium salts engage in N-alkylation and in situ depyridylation to afford secondary aryl-alkyl amines without any overalkylation products. The method overcomes classical challenges in selective amine alkylation by accomplishing alkylation via transient, highly nucleophilic pyridinium ylide intermediates and can be applied in the context of complex molecular scaffolds. These findings establish N-aminopyridinium salts as ammonia synthons in synthetic chemistry and a strategy to control the extent of amine alkylation.

Prediction of compost organic matter via color sensor.

Composted materials serve as an effective soil nutrient amendment. Organic matter in compost plays an important role in quantifying composted materials overall quality and nutrient content. Measuring organic matter content traditionally takes considerable time, resources, and various laboratory equipment (e.g., oven, muffle furnace, crucibles, precision balance). Much like the quantitative color indices (e.g., sRGB R, sRGB G, sRGB B, CIEL*a* b*) derived from the low-cost NixPro2 color sensor have proven adept at predicting soil organic matter in-situ, the NixPro2 color sensor has the potential to be effective for predicting organic matter in composted materials without the need for traditional laboratory methods. In this study, a total of 200 compost samples (13 different compost types) were measured for organic matter content via traditional loss-on-ignition (LOI) and via the NixPro2 color sensor. The NixPro2 color sensor showed promising results with an LOI-prediction model utilizing the CIEL*a* b* color model through the application of the Generalized Additive Model (GAM) algorithm yielding an excellent prediction accuracy (validation R2 = 0.87, validation RMSE = 4.66 %). Moreover, the PCA scoreplot differentiated the three lowest organic matter compost types from the remaining 10 compost types. These results have valuable practical significance for the compost industry by predicting compost organic matter in real time without the need for laborious, time-consuming methods.

A multi-environmental source approach to explore associations between metals exposure and olfactory identification among school-age children residing in northern Italy.

BACKGROUND: Metal exposures can adversely impact olfactory function. Few studies have examined this association in children. Further, metal exposure occurs as a mixture, yet previous studies of metal-associated olfactory dysfunction only examined individual metals. Preventing olfactory dysfunctions can improve quality of life and prevent neurodegenerative diseases with long-term health implications. OBJECTIVE: We aimed to test the association between exposure to a mixture of 12 metals measured in environmental sources and olfactory function among children and adolescents residing in the industrialized province of Brescia, Italy. METHODS: We enrolled 130 children between 6 and 13 years old (51.5% females) and used the "Sniffin' Sticks" test to measure olfactory performance in identifying smells. We used a portable X-ray fluorescence instrument to determine concentrations of metals (arsenic (As), calcium, cadmium (Cd), chromium, copper, iron, manganese, lead (Pb), antimony, titanium, vanadium and zinc) in outdoor and indoor deposited dust and soil samples collected from participants' households. We used an extension of weighted quantile sum (WQS) regression to test the association between exposure to metal mixtures in multiple environmental media and olfactory function adjusting for age, sex, socio-economic status, intelligence quotient and parents' smoking status. RESULTS: A higher multi-source mixture was significantly associated with a reduced Sniffin' Sticks identification score (ß = -0.228; 95% CI -0.433, -0.020). Indoor dust concentrations of Pb, Cd and As provided the strongest contributions to this association (13.8%, 13.3% and 10.1%, respectively). The metal mixture in indoor dust contributed more (for 8 metals out of 12) to the association between metals and olfactory function compared to soil or outdoor dust. IMPACT STATEMENT: Among a mixture of 12 metals measured in three different environmental sources (soil, outdoor and indoor dust), we identified Pb, Cd and As measured in indoor dust as the main contributors to reduced olfactory function in children and adolescents residing in an industrialized area. Exposure to indoor pollution can be effectively reduced through individual and public health interventions allowing to prevent the deterioration of olfactory functions. Moreover, the identification of the factors that can deteriorate olfactory functions can be a helpful instrument to improve quality of life and prevent neurodegenerative diseases as long-term health implications.

The 18S rRNA Methyltransferase DIMT-1 Regulates Lifespan in the Germline Later in Life.

Ribosome heterogeneity has emerged as an important regulatory control feature for determining which proteins are synthesized, however, the influence of age on ribosome heterogeneity is not fully understood. Whether mRNA transcripts are selectively translated in young versus old cells and whether dysregulation of this process drives organismal aging is unknown. Here we examined the role of ribosomal RNA (rRNA) methylation in maintaining appropriate translation as organisms age. In a directed RNAi screen, we identified the 18S rRNA N6'-dimethyl adenosine (m6,2A) methyltransferase, dimt-1, as a regulator of C. elegans lifespan and stress resistance. Lifespan extension induced by dimt-1 deficiency required a functional germline and was dependent on the known regulator of protein translation, the Rag GTPase, raga-1, which links amino acid sensing to the mechanistic target of rapamycin complex (mTORC)1. Using an auxin-inducible degron tagged version of dimt-1, we demonstrate that DIMT-1 functions in the germline after mid-life to regulate lifespan. We further found that knock-down of dimt-1 leads to selective translation of transcripts important for stress resistance and lifespan regulation in the C. elegans germline in mid-life including the cytochrome P450 daf-9, which synthesizes a steroid that signals from the germline to the soma to regulate lifespan. We found that dimt-1 induced lifespan extension was dependent on the daf-9 signaling pathway. This finding reveals a new layer of proteome dysfunction, beyond protein synthesis and degradation, as an important regulator of aging. Our findings highlight a new role for ribosome heterogeneity, and specific rRNA modifications, in maintaining appropriate translation later in life to promote healthy aging.

A pilot study to identify factors associated with frailty within the World Trade Center general responder cohort.

BACKGROUND: Given the significant exposures experienced by the World Trade Center (WTC) general responders, there is increasing interest in understanding the effect of these exposures on aging in this population. We aim to identify factors that may be associated with frailty, a clinical syndrome characterized by a decrease in one's reserve that has been linked to poor health outcomes. METHODS: WTC general responders enrolled in the WTC Health Program aged 50 and older provided informed consent. Validated frailty assessments, the Frailty Phenotype (with the Johns Hopkins Frailty Assessment Calculator) along with the FRAIL scale, categorized nonfrail from prefrail/frail. Fall risk, functional status, and cognition were also assessed. WTC variables, including an identified WTC-certified condition, were utilized. The risk of frailty was estimated using log binomial regression analysis. A 95% confidence interval (CI) was used to estimate the prevalence ratio (PR). RESULTS: One hundred and six participants were included; 38 (35.8%) were classified as pre-frail or frail. More of the pre-frail/frail group were obese (57.9% vs. 25%; p = 0.004) and had a WTC-certified condition (78.9% vs. 58.8%; p = 0.036). Obesity (PR = 2.43, 95% CI = 1.31, 4.53), a WTC-certified condition (PR = 1.77, 95% CI = 1.09, 2.89), and risk of falling (PR = 1.97, 95% CI = 1.01, 3.84) were independently associated with frailty. CONCLUSIONS: Obesity and having a WTC-certified condition were found to be risk factors for frailty in our pilot study. Future work may focus on further identifying risk factors for frailty in the larger WTC general responder population.

NP3 MS Workflow: An Open-Source Software System to Empower Natural Product-Based Drug Discovery Using Untargeted Metabolomics.

Natural products (or specialized metabolites) are historically the main source of new drugs. However, the current drug discovery pipelines require miniaturization and speeds that are incompatible with traditional natural product research methods, especially in the early stages of the research. This article introduces the NP3 MS Workflow, a robust open-source software system for liquid chromatography-tandem mass spectrometry (LC-MS/MS) untargeted metabolomic data processing and analysis, designed to rank bioactive natural products directly from complex mixtures of compounds, such as bioactive biota samples. NP3 MS Workflow allows minimal user intervention as well as customization of each step of LC-MS/MS data processing, with diagnostic statistics to allow interpretation and optimization of LC-MS/MS data processing by the user. NP3 MS Workflow adds improved computing of the MS2 spectra in an LC-MS/MS data set and provides tools for automatic [M + H]+ ion deconvolution using fragmentation rules; chemical structural annotation against MS2 databases; and relative quantification of the precursor ions for bioactivity correlation scoring. The software will be presented with case studies and comparisons with equivalent tools currently available. NP3 MS Workflow shows a robust and useful approach to select bioactive natural products from complex mixtures, improving the set of tools available for untargeted metabolomics. It can be easily integrated into natural product-based drug-discovery pipelines and to other fields of research at the interface of chemistry and biology.

Acute and chronic eosinophilic pneumonia: an overview.

Acute and chronic eosinophilic pneumonia (AEP and CEP) include a group of rare interstitial lung diseases characterized by peripheral blood eosinophilia, increased eosinophils in bronchoalveolar lavage fluid, or eosinophilic infiltration of lung parenchyma. AEP is characterized by rapid onset, fast response to steroid treatment, and no relapse. CEP is characterized by marked tissue and peripheral blood eosinophilia, rapid response to steroid therapy, and tendency to disease recurrence. In addition, we briefly describe other eosinophilic lung diseases that must be considered in differential diagnosis of AEP and CEP. Eosinophilic pneumonias may be idiopathic or due to known causes such as medications or environmental exposure. At variance with previous reviews on this topic, a particular look in this overview was directed at pathological findings and radiological patterns.

Peroxiredoxin 6 suppresses ferroptosis in lung endothelial cells.

Peroxiredoxin 6 (Prdx6) repairs peroxidized membranes by reducing oxidized phospholipids, and by replacing oxidized sn-2 fatty acyl groups through hydrolysis/reacylation by its phospholipase A2 (aiPLA2) and lysophosphatidylcholine acyltransferase activities. Prdx6 is highly expressed in the lung, and intact lungs and cells null for Prdx6 or with single-point mutations that inactivate either Prdx6-peroxidase or aiPLA2 activity alone exhibit decreased viability, increased lipid peroxidation, and incomplete repair when exposed to paraquat, hyperoxia, or organic peroxides. Ferroptosis is form of cell death driven by the accumulation of phospholipid hydroperoxides. We studied the role of Prdx6 as a ferroptosis suppressor in the lung. We first compared the expression Prdx6 and glutathione peroxidase 4 (GPx4) and visualized Prdx6 and GPx4 within the lung. Lung Prdx6 mRNA levels were five times higher than GPx4 levels. Both Prdx6 and GPx4 localized to epithelial and endothelial cells. Prdx6 knockout or knockdown sensitized lung endothelial cells to erastin-induced ferroptosis. Cells with genetic inactivation of either aiPLA2 or Prdx6-peroxidase were more sensitive to ferroptosis than WT cells, but less sensitive than KO cells. We then conducted RNA-seq analyses in Prdx6-depleted cells to further explore how the loss of Prdx6 sensitizes lung endothelial cells to ferroptosis. Prdx6 KD upregulated transcriptional signatures associated with selenoamino acid metabolism and mitochondrial function. Accordingly, Prdx6 deficiency blunted mitochondrial function and increased GPx4 abundance whereas GPx4 KD had the opposite effect on Prdx6. Moreover, we detected Prdx6 and GPx4 interactions in intact cells, suggesting that both enzymes cooperate to suppress lipid peroxidation. Notably, Prdx6-depleted cells remained sensitive to erastin-induced ferroptosis despite the compensatory increase in GPx4. These results show that Prdx6 suppresses ferroptosis in lung endothelial cells and that both aiPLA2 and Prdx6-peroxidase contribute to this effect. These results also show that Prdx6 supports mitochondrial function and modulates several coordinated cytoprotective pathways in the pulmonary endothelium.

Utility of motor-evoked potentials in contemporary open thoracoabdominal aortic repair.

OBJECTIVE: Paraplegia remains one of the major complications of contemporary open thoracoabdominal aortic aneurysm (TAAA) repair. Intraoperative motor-evoked potentials (MEPs) act as a surrogate measure for spinal cord homeostasis. The purpose of this study was to evaluate the results of intraoperative neuromonitoring in contemporary TAAA repair and its association with postoperative spinal cord ischemia (SCI). METHODS: Patients who underwent open type 2 or 3 TAAA or completion aortic repair using intraoperative neuromonitoring were identified between May 2006 and November 2023. Patient demographics, comorbidities, indication for the procedure, procedural details, and outcomes were recorded. The groups were divided based on type of repair, and univariate statistics were then used to evaluate the association of these metrics vs the type of repair. RESULTS: Seventy-nine patients underwent open type 2 (N = 41) and 3 (N = 23) TAAA and completion aortic (N = 15; open in 14 and endovascular in 1) repairs by a single surgeon. The cohort was predominantly male (N = 48, 60.8%) with a mean age of 52.5 ± 16.2 years. There was a high incidence of hypertension (N = 53, 67.1%), smoking history (N = 42, 53.1%), and connective tissue disorders (N = 37, 46.8%). Operative indications included dissection-related (N = 50, 63.3%) and degenerative (N = 26, 32.9%) TAAA and dissection-related malperfusion (N = 3, 3.8%). Left heart bypass was often (N = 73, 92.4%) used for distal aortic perfusion, and cerebrospinal fluid drainage (N = 77, 97.5%) was a common adjunct. MEPs were classified as no change (N = 43, 54.4%), reversible change (N = 26, 32.9%), irreversible change (N = 4, 5.1%), and unreliable (N = 6, 7.6%). MEP changes were predominantly bilateral (N = 70, 88.6%) and occurred most often during repair of the abdominal aortic segment (N = 13, 16.5%). The median number of replaced vertebral levels was associated with MEP changes (P = .013). SCI was only observed in repairs greater than 6 replaced vertebral levels with an overall frequency of 17.7%. It was most prevalent in completion aortic repairs (26.7%). Immediate and delayed SCI occurred in 10.1% and 7.6% of patients, respectively; it was most commonly (71.8%) reversible. Permanent paraplegia occurred in four patients (5.1%), with equal immediate and delayed onsets. MEPs demonstrated poor sensitivity (53.9%) and specificity (62.3%) for SCI; however, there was a high negative predictive value (86.4%) in this population. In-hospital mortality occurred in five (6.3%) patients. CONCLUSIONS: No changes in intraoperative MEPs are highly predictive of spinal cord homeostasis. The number of replaced vertebral levels and previous aortic repair should guide intraoperative neuroprotective measures including intercostal reimplantation and should take precedence over intraoperative monitoring, especially when MEP changes occur.

Study of erythrocyte sedimentation in human blood through the photoacoustic signals analysis.

Introduction: In this study, we utilized the pulsed photoacoustic (PA) technique to analyze globular sedimentation in whole human blood, with a focus on distinguishing between healthy individuals and those with hemolytic anemia. Methods: Blood samples were collected from both healthy individuals (women and men) and those with hemolytic anemia, and temporal and spectral parameters of PA signals were employed for analysis. Results: Significant differences (p < 0.05) were observed in PA metrics between the two groups. The proposed spectral analysis allowed significant differentiation within a 25-minute measurement window. Anemic blood samples exhibited higher erythrocyte sedimentation rate (ESR) values, indicating increased erythrocyte aggregation. Discussion: This study underscores the potential of PA signal analysis in ESR assessment as an efficient method for distinguishing between healthy and anemic blood, surpassing traditional approaches. It represents a promising contribution to the development of precise and sensitive techniques for analyzing human blood samples in clinical settings.

Social isolation consequences: lessons from COVID-19 pandemic in a context of dynamic lock-down in Chile.

BACKGROUND: Chile did not adopt general and unified lockdowns for the whole nation but organized itself with dynamic and sometimes irregular lockdowns. These dynamics and consequences of social isolation could be generalized to other contexts of isolation such as those affecting minorities such as immigrants, prisoners, refugees. METHODS: In this study, we investigated the physical and mental health symptoms associated with lifestyle changes due to lockdown among university students in Chile. We examined psychopathological variations in relation to mental health problems in a healthy young population. Our goal was to develop interventions to address these new psychosocial problems in potentially comparable post-pandemic contexts. From May 10th 2021 to June 2th 2021, 420 University students took part in an anonymous survey asking for information on habits and symptoms that emerged during the lockdown in response to the COVID-19 pandemic. Three health outcomes were assessed: digestive disorders; headache; fear of COVID-19. Covariates including conditions and lifestyle during the pandemic, SARS-CoV-2 infections in the family, financial situation and productivity were considered in the analysis. RESULTS: Participants experienced headache and fear of COVID-19 quite frequently during the lockdown period. More than half of the sample also experienced social isolation. Female gender, sleep quality, memory difficulties, and a change in eating habits resulted associated with an increased risk of health outcomes such as headaches and digestive disorders. CONCLUSIONS: The results of this study fit within an original pandemic context: The results of this study can help identify needs and promote solutions applicable to different contexts. Future interventions should focus on the promotion and implementation of healthy habits focused on sleep hygiene, psychoeducation on the use of mobile devices and gender medicine with the support of healthcare organizations and University.

Sex-specific associations between co-exposure to multiple metals and externalizing symptoms in adolescence and young adulthood.

Externalizing disorders, such as attention-deficit/hyperactivity disorder (ADHD), account for the majority of the child/adolescent referrals to mental health services and increase risk for later-life psychopathology. Although the expression of externalizing disorders is more common among males, few studies have addressed how sex modifies associations between metal exposure and adolescent externalizing symptoms. This study aimed to examine sex-specific associations between co-exposure to multiple metals and externalizing symptoms in adolescence and young adulthood. Among 150 adolescents and young adults (55% female, ages: 15-25 years) enrolled in the Public Health Impact of Metals Exposure (PHIME) study in Brescia, Italy, we measured five metals (manganese (Mn), lead (Pb), copper (Cu), chromium (Cr), nickel (Ni)) in four biological matrices (blood, urine, hair, and saliva). Externalizing symptoms were assessed using the Achenbach System of Empirically Based Assessment (ASEBA) Youth Self-Report (YSR) or Adult Self Report (ASR). Using generalized weighted quantile sum (WQS) regression, we investigated the moderating effect of sex (i.e., assigned at birth) on associations between the joint effect of exposure to the metal mixture and externalizing symptoms, adjusting for age and socioeconomic status. We observed that metal mixture exposure was differentially associated with aggressive behavior in males compared to females (ß = -0.058, 95% CI [-0.126, -0.009]). In males, exposure was significantly associated with more externalizing problems, and aggressive and intrusive behaviors, driven by Pb, Cu and Cr. In females, exposure was not significantly associated with any externalizing symptoms. These findings suggest that the effect of metal exposure on externalizing symptoms differs in magnitude between the sexes, with males being more vulnerable to increased externalizing symptoms following metal exposure. Furthermore, our findings support the hypothesis that sex-specific vulnerabilities to mixed metal exposure during adolescence/young adulthood may play a role in sex disparities observed in mental health disorders, particularly those characterized by externalizing symptoms.

An Industry-Relevant Metal Mixture, Iron Status, and Reported Attention-Related Behaviors in Italian Adolescents.

BACKGROUND: Exposure to environmental metals has been consistently associated with attention and behavioral deficits in children, and these associations may be modified by coexposure to other metals or iron (Fe) status. However, few studies have investigated Fe status as a modifier of a metal mixture, particularly with respect to attention-related behaviors. METHODS: We used cross-sectional data from the Public Health Impact of Metals Exposure study, which included 707 adolescents (10-14 years of age) from Brescia, Italy. Manganese, chromium, and copper were quantified in hair samples, and lead was quantified in whole blood, using inductively coupled plasma mass spectrometry. Concentrations of Fe status markers (ferritin, hemoglobin, transferrin) were measured using immunoassays or luminescence assays. Attention-related behaviors were assessed using the Conners Rating Scales Self-Report Scale-Long Form, Parent Rating Scales Revised-Short Form, and Teacher Rating Scales Revised-Short Form. We employed Bayesian kernel machine regression to examine associations of the metal mixture with these outcomes and evaluate Fe status as a modifier. RESULTS: Higher concentrations of the metals and ferritin were jointly associated with worse self-reported attention-related behaviors: metals and ferritin set to their 90th percentiles were associated with 3.0% [ß=0.03; 95% credible interval (CrI): -0.01, 0.06], 4.1% (ß=0.04; 95% CrI: 0.00, 0.08), and 4.1% (ß=0.04; 95% CrI: 0.00, 0.08) higher T-scores for self-reported attention deficit/hyperactivity disorder (ADHD) index, inattention, and hyperactivity, respectively, compared with when metals and ferritin were set to their 50th percentiles. These associations were driven by hair manganese, which exhibited nonlinear associations with all self-reported scales. There was no evidence that Fe status modified the neurotoxicity of the metal mixture. The metal mixture was not materially associated with any parent-reported or teacher-reported scale. CONCLUSIONS: The overall metal mixture, driven by manganese, was adversely associated with self-reported attention-related behavior. These findings suggest that exposure to multiple environmental metals impacts adolescent neurodevelopment, which has significant public health implications. https://doi.org/10.1289/EHP12988.

Testacosides A-D, glycoglycerolipids produced by Microbacterium testaceum isolated from Tedania brasiliensis.

Marine bacteria living in association with marine sponges have proven to be a reliable source of biologically active secondary metabolites. However, no studies have yet reported natural products from Microbacterium testaceum spp. We herein report the isolation of a M. testaceum strain from the sponge Tedania brasiliensis. Molecular networking analysis of bioactive pre-fractionated extracts from culture media of M. testaceum enabled the discovery of testacosides A-D. Analysis of spectroscopic data and chemical derivatizations allowed the identification of testacosides A-D as glycoglycerolipids bearing a 1-[α-glucopyranosyl-(1 → 3)-(α-mannopyranosyl)]-glycerol moiety connected to 12-methyltetradecanoic acid for testacoside A (1), 14-methylpentadecanoic acid for testacoside B (2), and 14-methylhexadecanoic acid for testacosides C (3) and D (4). The absolute configuration of the monosaccharide residues was determined by 1H-NMR analysis of the respective diastereomeric thiazolidine derivatives. This is the first report of natural products isolated from cultures of M. testaceum. KEY POINTS: • The first report of metabolites produced by Microbacterium testaceum. • 1-[α-Glucopyranosyl-(1 → 3)-(α-mannopyranosyl)]-glycerol lipids isolated and identified. • Microbacterium testaceum strain isolated from the sponge Tedania brasiliensis.

Analysis of distinct blaKPC-encoding plasmids in an Enterobacter kobei strain recovered from recreational coastal water.

In this study we present an in-depth characterization of two blaKPC-2 encoding plasmids found in the Enterobacter kobei FL23 strain recovered from recreational coastal water. The plasmids belong to distinct incompatibility groups and carry a diverse collection of resistance genes. Furthermore, the genetic context of the blaKPC-2 gene was different in each of them. While pEkFL23-IncX3 presents a new Tn4401k, a new isoform, similar to Tn4401b but with a truncated tnpA and a deleted tnpR; pEkFL23-IncU/P6 carries a new isoform of a non-Tn4401 element (NTEKPC), named NTEKPC-IIh. Its difference from NTEKPC-IId is the truncated Tn3 resolvase upstream blaKPC-2. Capacity of conjugation, maintenance rates and fitness cost of both replicons were also assessed. Both were transferred after mating assays, whereas only pEkFL23-IncX3 was transferred under the adverse conditions of Marine broth at 25 °C as a mating platform. A remarkable stability of both plasmids was observed in the parental and transconjugant strains. Finally, both replicons did not impose a significant fitness cost to their transformant hosts, with pEkFL23-IncU/P6 conferring a statistically significant (p < 0.05) advantage in head-to-head competitions. Our findings show that E. kobei FL23 is a disquieting case of a carbapenem-resistant bacteria identified in a community setting, being a possible silent disseminator of two seemingly stable and metabolic weightless multidrug resistance plasmids.

Metabolomics approach to understand molecular mechanisms involved in fungal pathogen-citrus pathosystems.

Citrus is a crucial crop with a significant economic impact globally. However, postharvest decay caused by fungal pathogens poses a considerable threat, leading to substantial financial losses. Penicillium digitatum, Penicillium italicum, Geotrichum citri-aurantii and Phyllosticta citricarpa are the main fungal pathogens, causing green mold, blue mold, sour rot and citrus black spot diseases, respectively. The use of chemical fungicides as a control strategy in citrus raises concerns about food and environmental safety. Therefore, understanding the molecular basis of host-pathogen interactions is essential to find safer alternatives. This review highlights the potential of the metabolomics approach in the search for bioactive compounds involved in the pathogen-citrus interaction, and how the integration of metabolomics and genomics contributes to the understanding of secondary metabolites associated with fungal virulence and the fungal infection mechanisms. Our goal is to provide a pipeline combining metabolomics and genomics that can effectively guide researchers to perform studies aiming to contribute to the understanding of the fundamental chemical and biochemical aspects of pathogen-host interactions, in order to effectively develop new alternatives for fungal diseases in citrus cultivation. We intend to inspire the scientific community to question unexplored biological systems, and to employ diverse analytical approaches and metabolomics techniques to address outstanding questions about the non-studied pathosystems from a chemical biology perspective.

Antimalarial Drug Combination Predictions Using the Machine Learning Synergy Predictor (MLSyPred©) tool.

PURPOSE: Antimalarial drug resistance is a global public health problem that leads to treatment failure. Synergistic drug combinations can improve treatment outcomes and delay the development of drug resistance. Here, we describe the implementation of a freely available computational tool, Machine Learning Synergy Predictor (MLSyPred©), to predict potential synergy in antimalarial drug combinations. METHODS: The MLSyPred© synergy prediction method extracts molecular fingerprints from the drugs' biochemical structures to use as features and also cleans and prepares the raw data. Five machine learning algorithms (Logistic Regression, Random Forest, Support vector machine, Ada Boost, and Gradient Boost) were implemented to build prediction models. Implementation and application of the MLSyPred© tool were tested using datasets from 1540 combinations of 79 drugs and compounds biologically evaluated in pairs for three strains of Plasmodium falciparum (3D7, HB3, and Dd2). RESULTS: The best prediction models were obtained using Logistic Regression for antimalarials with the strains Dd2 and HB3 (0.81 and 0.70 AUC, respectively) and Random Forest for antimalarials with 3D7 (0.69 AUC). The MLSyPred© tool yielded 45% precision for synergistically predicted antimalarial drug combinations that were annotated and biologically validated, thus confirming the functionality and applicability of the tool. CONCLUSION:  The MLSyPred© tool is freely available and represents a promising strategy for discovering potential synergistic drug combinations for further development as novel antimalarial therapies.

Dynamic modeling of photoacoustic sensor data to classify human blood samples.

The photoacoustic effect is an attractive tool for diagnosis in several biomedical applications. Analyzing photoacoustic signals, however, is challenging to provide qualitative results in an automated way. In this work, we introduce a dynamic modeling scheme of photoacoustic sensor data to classify blood samples according to their physiological status. Thirty-five whole human blood samples were studied with a state-space model estimated by a subspace method. Furthermore, the samples are classified using the model parameters and the linear discriminant analysis algorithm. The classification performance is compared with time- and frequency-domain features and an autoregressive-moving-average model. As a result, the proposed analysis can predict five blood classes: healthy women and men, microcytic and macrocytic anemia, and leukemia. Our findings indicate that the proposed method outperforms conventional signal processing techniques to analyze photoacoustic data for medical diagnosis. Hence, the method is a promising tool in point-of-care devices to detect hematological diseases in clinical scenarios.