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1.
J Thorac Imaging ; 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38800956

RESUMEN

OBJECTIVES: To investigate the predictive value of coronary computed tomography angiography-derived fractional flow reserve (CT-FFR) before percutaneous coronary intervention (PCI) to predict target vessel failure (TVF) after stent implantation. METHODS: This retrospective study included 429 patients (429 vessels) who underwent PCI and stent implantation after CCTA within 3 months. All patients underwent coronary stent implantation between January 2012 and December 2019. A dedicated workstation (Syngo Via, Siemens) was used to analyze and measure the CT-FFR value. The cut-off values of pre-PCI CT-FFR for predicting TVF were defined as 0.80 and the value using the log-rank maximization method, respectively. The primary outcome was TVF, defined as a composite of cardiac death, target vessel myocardial infarction, and clinically driven target vessel revascularization (TVR), which was a secondary outcome. RESULTS: During a median 64.0 months follow-up, the cumulative incidence of TVF was 7.9% (34/429). The cutoff value of pre-PCI CT-FFR based on the log-rank maximization method was 0.74, which was the independent predictor for TVF [hazard ratio (HR): 2.61 (95% CI: 1.13, 6.02); P=0.024] and TVR [HR: 3.63 (95%CI: 1.25, 10.51); P=0.018]. Compared with the clinical risk factor model, pre-PCI CT-FFR significantly improved the reclassification ability for TVF [net reclassification improvement (NRI), 0.424, P<0.001; integrative discrimination index (IDI), 0.011, P=0.022]. Adding stent information to the prediction model resulted in an improvement in reclassification for the TVF (C statistics: 0.711, P=0.001; NRI: 0.494, P<0.001; IDI: 0.020, P=0.028). CONCLUSIONS: Pre-PCI CT-FFR ≤0.74 was an independent predictor for TVF or TVR, and integration of clinical, pre-PCI CT-FFR, and stent information models can provide a better risk stratification model in patients with stent implantation.

2.
Microbiol Spectr ; 12(5): e0255823, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38526296

RESUMEN

This study aimed to investigate the prognostic value of a novel droplet digital polymerase chain reaction (DDPCR) assay in sepsis patients. In this prospective cohort study, univariable and multivariable Cox regressions were used to assess risk factors for 28-day mortality. We also monitored pathogen load together with clinical indicators in a subgroup of the cohort. A total of 107 sepsis patients with positive baseline DDPCR results were included. Detection of poly-microorganisms [adjusted hazard ratio (HR) = 3.19; 95% confidence interval (CI) = 1.34-7.62; P = 0.009], high Charlson Comorbidity Index (CCI) score (adjusted HR = 1.14; 95% CI = 1.01-1.29; P = 0.041), and Sequential Organ Failure Assessment (SOFA) score (adjusted HR = 1.18; 95% CI = 1.05-1.32; P = 0.005) at baseline were independent risk factors for 28-day mortality while initial pathogen load was not associated (adjusted HR = 1.17; 95% CI = 0.82-1.66; P = 0.385). Among 63 patients with serial DDPCR results, an increase in pathogen load at days 6-8 compared to baseline was a risk factor for 28-day mortality (P = 0.008). Also, pathogen load kinetics were significantly different between day-28 survivors and nonsurvivors (P = 0.022), with a decline overtime only in survivors and an increase from days 3 and 4 to days 6-8 in nonsurvivors. Using DDPCR technique, we found that poly-microorganisms detected and increased pathogen load a week after sepsis diagnosis were associated with poor prognosis.IMPORTANCEThis prospective study was initiated to explore the prognostic implications of a novel multiplex PCR assay in sepsis. Notably, our study was the largest cohort of sepsis with droplet digital polymerase chain reaction pathogen monitoring to date, allowing for a comprehensive evaluation of the prognostic significance of both pathogen species and load. We found that detection of poly-microorganisms was an independent risk factors for 28-day mortality. Also, pathogen load increase 1 week after sepsis diagnosis was a risk factor for 28-day mortality, and differential pathogen load kinetics were identified between day-28 survivors and nonsurvivors. Overall, this study demonstrated that pathogen species and load were highly correlated with sepsis prognosis. Patients exhibiting conditions mentioned above face a more adverse prognosis, suggesting the potential need for an escalation of antimicrobial therapy.Registered at ClinicalTrials.gov (NCT05190861).


Asunto(s)
Reacción en Cadena de la Polimerasa , Sepsis , Humanos , Sepsis/microbiología , Sepsis/mortalidad , Sepsis/diagnóstico , Estudios Prospectivos , Femenino , Masculino , Pronóstico , Persona de Mediana Edad , Anciano , Reacción en Cadena de la Polimerasa/métodos , Factores de Riesgo , Carga Bacteriana/métodos , Bacterias/genética , Bacterias/aislamiento & purificación , Bacterias/clasificación , Anciano de 80 o más Años , Cinética
3.
Shock ; 61(3): 367-374, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38407987

RESUMEN

ABSTRACT: Objective: To achieve a better prediction of in-hospital mortality, the Sequential Organ Failure Assessment (SOFA) score needs to be adjusted and combined with comorbidities. This study aims to enhance the prediction of SOFA score for in-hospital mortality in patients with Sepsis-3. Methods: This study adjusted the maximum SOFA score within the first 3 days (Max Day3 SOFA) in relation to in-hospital mortality using logistic regression and incorporated the age-adjusted Charlson Comorbidity Index (aCCI) as a continuous variable to build the age-adjusted Charlson Comorbidity Index-Sequential Organ Failure Assessment (aCCI-SOFA) model. The outcome was in-hospital mortality. We developed, internally validated, and externally validated the aCCI-SOFA model using cohorts of Sepsis-3 patients from the MIMIC-IV, MIMIC-III (CareVue), and the FAHWMU cohort. The predictive performance of the model was assessed through discrimination and calibration, which was assessed using the area under the receiver operating characteristic and calibration curves, respectively. The overall predictive effect was evaluated using the Brier score. Measurements and main results: Compared with the Max Day3 SOFA, the aCCI-SOFA model showed significant improvement in area under the receiver operating characteristic with all cohorts: development cohort (0.81 vs 0.75, P < 0.001), internal validation cohort (0.81 vs 0.76, P < 0.001), MIMIC-III (CareVue) cohort (0.75 vs 0.68, P < 0.001), and FAHWMU cohort (0.72 vs 0.67, P = 0.001). In sensitivity analysis, it was suggested that the application of aCCI-SOFA in early nonseptic shock patients had greater clinical value, with significant differences compared with the original SOFA scores in all cohorts ( P < 0.05). Conclusion: For septic patients in intensive care unit, the aCCI-SOFA model exhibited superior predictive performance. The application of aCCI-SOFA in early nonseptic shock patients had greater clinical value.


Asunto(s)
Sepsis , Humanos , Mortalidad Hospitalaria , Estudios Retrospectivos , Pronóstico , Unidades de Cuidados Intensivos , Curva ROC
4.
Opt Express ; 31(21): 35054-35067, 2023 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-37859246

RESUMEN

Immersion gratings have high dispersion efficiency and have important application value in miniaturized imaging spectrometers, but its serious dispersion nonlinearity causes difficulties in calibration and image processing, which limits its application range. To solve this, this paper presents a design method for a two-material linear dispersion immersion grating device design method, and a compact small F-number immersion grating spectrometer based on it. First the vector form dispersion equation of the two-material immersion grating is derived and the linear spectral dispersion immersion grating design process is given, then a compact small F-number uniform dispersion imaging spectrometer is given as a design example using the proposed method. The results show that when the operating band of the system is 1590-1675 nm, the spectral resolution is better than 0.25 nm, and F-number can achieve better than 2. Compared with traditional single-material immersion grating imaging spectrometer, the designed imaging spectrometer dispersion linearity is significantly improved. Finally, the influence of prism materials, structure parameters and grating parameters on dispersion nonlinearity is analyzed. Design and analysis results show that the proposed two-material immersion grating device has much better spectral dispersion nonlinearity correction ability, and its design method can provide reference to the compact spectrometer design based on immersion gratings.

5.
J Agric Food Chem ; 71(42): 15456-15465, 2023 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-37843466

RESUMEN

Semiochemicals produced by microbes in hemipteran honeydew play an important role in mediating the ant-hemipteran interaction. However, the specific volatile compounds and their origins remain unclear. Here, we found that honeydew produced by Phenacoccus solenopsis exhibited strong attractiveness to fire ant workers, but sterilized honeydew was much less attractive. Four compounds were identified from the honeydew volatiles, including 1-octen-3-ol, limonene, phenylethyl alcohol, and 2,4-ditert-butylphenol. All the identified compounds triggered strong electroantennography response of fire ants and showed repellence at relatively high concentrations while attractiveness at low concentrations to fire ant workers. Furthermore, six bacterial isolates were identified based on 16S rRNA sequencing, namely, Bacillus, Brachybacterium, Kocuria, Microbacterium, Pseudomonas, and Staphylococcus. Fire ants exhibited a strong preference for Brachybacterium, Kocuria, and Microbacterium, suggesting that these bacterial isolates are involved in the attracting effect of honeydew. Both limonene and phenylethyl alcohol were detected from Brachybacterium, while limonene was only detected from Kocuria, and phenylethyl alcohol was exclusively detected from Microbacterium. Reinoculation of these bacteria restored the attractiveness of honeydew to fire ants, and the active compounds, limonene and phenylethyl alcohol, were detectable in bacteria-reinoculated honeydew. Collectively, our results reveal the active compounds in hemipteran honeydew and their association with honeydew bacteria. The findings will contribute to the development of novel attractants for efficient monitoring of fire ants.


Asunto(s)
Hormigas , Alcohol Feniletílico , Animales , Feromonas/farmacología , Limoneno , ARN Ribosómico 16S/genética , Simbiosis/fisiología , Bacterias/genética
6.
Insects ; 14(9)2023 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-37754709

RESUMEN

Bacteria associated with insects potentially provide many beneficial services and have been well documented. Mutualism that relates to insects is widespread in ecosystems. However, the interrelation between "symbiotic bacteria" and "mutualism" has rarely been studied. We introduce three systems of mutualism that relate to insects (ants and honeydew-producing Hemiptera, fungus-growing insects and fungi, and plant persistent viruses and vector insects) and review the species of symbiotic bacteria in host insects, as well as their functions in host insects and the mechanisms underlying mutualism regulation. A deeper understanding of the molecular mechanisms and role of symbiotic bacteria, based on metagenomics, transcriptomics, proteomics, metabolomics, and microbiology, will be required for describing the entire interaction network.

7.
Pest Manag Sci ; 79(10): 4034-4047, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37287215

RESUMEN

BACKGROUND: Phenacoccus solenopsis is a polyphagous invasive mealybug that caused serious damage to crops worldwide. Phloem-sucking hemipterans are known to carry symbiotic microbes in their saliva. However, the role of salivary bacteria of P. solenopsis in modulating plant defenses remains limited. Exploring the impact of salivary bacteria on plant defense responses will contribute to the development of new targets for efficient control of invasive mealybugs. RESULTS: Salivary bacteria of the invasive mealybug P. solenopsis can suppress herbivore-induced plant defenses and thus enhance mealybug fitness. Mealybugs treated with an antibiotic showed decreased weight gain, fecundity and survival. Untreated mealybugs suppressed jasmonic acid (JA)-regulated defenses but activated salicylic acid (SA)-regulated defenses in cotton plants. In contrast, antibiotic-treated mealybugs triggered JA-responsive gene expression and JA accumulation, and showed shortened phloem ingestion. Reinoculating antibiotic-treated mealybugs with Enterobacteriaceae or Stenotrophomonas cultivated from mealybug saliva promoted phloem ingestion and fecundity, and restored the ability of mealybugs to suppress plant defenses. Fluorescence in situ hybridization visualization revealed that Enterobacteriaceae and Stenotrophomonas colonize salivary glands and are secreted into the mesophyll cells and phloem vessels. Exogenous application of the bacterial isolates to plant leaves inhibited JA-responsive gene expression and activated SA-responsive gene expression. CONCLUSION: Our findings imply that symbiotic bacteria in the saliva of the mealybug play an important role in manipulating herbivore-induced plant defenses, enabling this important pest to evade induced plant defenses and promoting its performance and destructive effects on crops. © 2023 Society of Chemical Industry.


Asunto(s)
Hormigas , Hemípteros , Animales , Hibridación Fluorescente in Situ , Hemípteros/fisiología , Herbivoria , Ácido Salicílico/farmacología , Ácido Salicílico/metabolismo , Antibacterianos/farmacología , Hormigas/metabolismo , Bacterias , Enterobacteriaceae/metabolismo
8.
Front Immunol ; 14: 1305025, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38274787

RESUMEN

Background: Idiopathic pulmonary fibrosis (IPF) is a chronic progressive interstitial lung disease. This study aimed to investigate the involvement of endoplasmic reticulum stress (ERS) in IPF and explore its correlation with immune infiltration. Methods: ERS-related differentially expressed genes (ERSRDEGs) were identified by intersecting differentially expressed genes (DEGs) from three Gene Expression Omnibus datasets with ERS-related gene sets. Gene Set Variation Analysis and Gene Ontology were used to explore the potential biological mechanisms underlying ERS. A nomogram was developed using the risk signature derived from the ERSRDEGs to perform risk assessment. The diagnostic value of the risk signature was evaluated using receiver operating characteristics, calibration, and decision curve analyses. The ERS score of patients with IPF was measured using a single-sample Gene Set Enrichment Analysis (ssGSEA) algorithm. Subsequently, a prognostic model based on the ERS scores was established. The proportion of immune cell infiltration was assessed using the ssGSEA and CIBERSORT algorithms. Finally, the expression of ERSRDEGs was validated in vivo and in vitro via RT-qPCR. Results: This study developed an 8-ERSRDEGs signature. Based on the expression of these genes, we constructed a diagnostic nomogram model in which agouti-related neuropeptide had a significantly greater impact on the model. The area under the curve values for the predictive value of the ERSRDEGs signature were 0.975 and 1.000 for GSE70866 and GSE110147, respectively. We developed a prognostic model based on the ERS scores of patients with IPF. Furthermore, we classified patients with IPF into two subtypes based on their signatures. The RT-qPCR validation results supported the reliability of most of our conclusions. Conclusion: We developed and verified a risk model using eight ERSRDEGs. These eight genes can potentially affect the progression of IPF by regulating ERS and immune responses.


Asunto(s)
Fibrosis Pulmonar Idiopática , Humanos , Reproducibilidad de los Resultados , Fibrosis Pulmonar Idiopática/genética , Algoritmos , Calibración , Estrés del Retículo Endoplásmico/genética
9.
Environ Sci Technol ; 56(17): 12440-12451, 2022 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-35944015

RESUMEN

Ants easily accumulate cadmium (Cd) from the food web in terrestrial ecosystems. Cd contamination may cause olfactory dysfunction and consequently disorders in the social behavior of ants. To explore the molecular mechanism underlying the effect of Cd exposure on the chemosensory process of ants, we characterized the Cd-induced variations in the expression of genes involved in chemoreception and electrophysiological and behavioral sensitivity to semiochemicals by using the red imported fire ant, Solenopsis invicta, as a model system. As a result, Cd exposure increased Cd accumulation and decreased the survival rate of S. invicta. Cd exposure altered the expression profiles of odor binding protein genes of S. invicta (SiOBPs). Specifically, SiOBP15 protein expression was upregulated upon Cd exposure. Both SiOBP7 and SiOBP15 exhibited high binding affinities to limonene, nonanal, and 2,4,6-trimethylpyridine. S. invicta exposed to Cd showed less sensitive electrophysiological and behavioral response to the three chemicals but exhibited sensitive perception to undecane. Silencing of SiOBP7 and SiOBP15 abolished the behavioral response of S. invicta to nonanal and undecane, respectively, suggesting that SiOBP7 and SiOBP15 play essential roles in the chemoreception of S. invicta. In general, our results suggest that Cd contamination may interfere with olfactory signal transduction by altering the expression of SiOBPs, consequently evoking chemosensory dysfunction in fire ants.


Asunto(s)
Hormigas , Animales , Hormigas/química , Hormigas/genética , Cadmio/toxicidad , Ecosistema
10.
Vox Sang ; 117(10): 1187-1194, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35851699

RESUMEN

BACKGROUND AND OBJECTIVES: Thrombocytopenia is common among sepsis patients. Platelet transfusions are frequently administered to increase platelet counts, but their clinical impacts remain unclear in sepsis-induced thrombocytopenia. The goal of this study was to explore the association between platelet transfusion and mortality in patients with sepsis-induced thrombocytopenia. MATERIALS AND METHODS: The study was based on the Medical Information Mart for Intensive Care (MIMIC) III database. Septic patients with severe thrombocytopenia (a platelet count ≤ 50/nl) were included in the study and were divided into two groups: a platelet transfusion group (PT group) and a no platelet transfusion group (NPT group). The primary outcome was in-hospital mortality, and the secondary outcomes were the length of intensive care unit (ICU) stay (LOS-ICU) and 90-day mortality. Propensity score matching multivariable logistic regression was used to reduce the imbalance. RESULTS: A total of 1733 patients were included: 296 patients were included in the PT group and 1437 patients were included in the NPT group. After propensity score matching, 296 paired patients constituted each group. Crude hospital mortality was significantly higher in the PT group than in the NPT group (145 [48.99%] vs. 567 [39.46%], p = 0.002). In the extended multivariable logistic models for hospital mortality, the odds ratio (OR) of receiving a platelet transfusion was consistently significant in all six models (OR range, 1.340-1.525, p < 0.05 for all). In the following subgroups, platelet transfusion was associated with increased in-hospital mortality: age > 60 years; sex: female; sequential organ failure assessment score ≤8; simplified acute physiology score ≤ 47; platelet count >29/nl and the complication of congestive heart failure. However, there were no significant differences in the 90-day mortality rate (170 [57.43%] vs. 741 [51.57%], p = 0.066) or the LOS-ICU (5.84 [2.68-11.78] vs. 4.94 [2.18-12.72], p = 0.442) between the two groups. All these results remained stable after adjustment for confounders and in the comparisons after propensity score matching. CONCLUSIONS: The propensity score-matched analysis showed that platelet transfusion was associated with increased in-hospital mortality in septic patients with severe thrombocytopenia (a platelet count ≤ 50/nl). However, it was not associated with 90-day mortality or the length of ICU stay.


Asunto(s)
Sepsis , Trombocitopenia , Femenino , Humanos , Unidades de Cuidados Intensivos , Persona de Mediana Edad , Recuento de Plaquetas , Transfusión de Plaquetas/efectos adversos , Puntaje de Propensión , Estudios Retrospectivos , Sepsis/complicaciones , Sepsis/terapia , Trombocitopenia/complicaciones , Trombocitopenia/terapia
11.
BMC Infect Dis ; 22(1): 630, 2022 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-35854212

RESUMEN

BACKGROUND: Sepsis is still a major public health concern and a medical emergency due to its high morbidity and mortality. Accurate and timely etiology diagnosis is crucial for sepsis management. As an emerging rapid and sensitive pathogen detection tool, digital droplet PCR (ddPCR) has shown promising potential in rapid identification of pathogens and antimicrobial resistance genes. However, the diagnostic value and clinical impact of ddPCR tests remains to be studied in patients with suspected sepsis. PROGRESS trial is aimed to evaluate the clinical effectiveness of a novel ddPCR assay compared with standard practice. METHODS: PROGRESS is a multicenter, open-label, pragmatic randomized controlled trial (pRCT) set in ten hospitals, including departments of infectious disease and intensive care units. In this study, a total of 2292 patients with suspected sepsis will be randomly assigned to two arms: the ddPCR group and the control group with a ratio of 3:1. The primary outcome is the diagnostic efficacy, that is, the sensitivity and specificity of the ddPCR assay compared with the synchronous blood culture. Secondary outcomes include the mortality rates and the mean Sequential Organ Failure Assessment (SOFA) score at follow-up time points, the length of stay in the hospital, the time to directed antimicrobial therapy, duration of broad-spectrum antibiotic use, and the EQ-5D-5L score on day 90. DISCUSSION: It is the first multicenter pragmatic RCT to explore the diagnostic efficacy and clinical impact of the ddPCR assay in patients with suspected sepsis, taking advantage of both RCT's ability to establish causality and the feasibility of pragmatic approaches in real-world studies (RWS). This trial will help us to get a comprehensive view of the assay's capacity for precise diagnosis and treatment of sepsis. It has the potential to monitor the pathogen load change and to guide the antimicrobial therapy, making a beneficial impact on the prognosis of sepsis patients. TRIAL REGISTRATION: ClinicalTrial.gov, NCT05190861. Registered January 13, 2022-'Retrospectively registered', https://clinicaltrials.gov/ct2/show/NCT05190861 .


Asunto(s)
Sepsis , Humanos , Estudios Multicéntricos como Asunto , Puntuaciones en la Disfunción de Órganos , Reacción en Cadena de la Polimerasa , Ensayos Clínicos Pragmáticos como Asunto , Pronóstico , Ensayos Clínicos Controlados Aleatorios como Asunto , Sepsis/diagnóstico , Sepsis/tratamiento farmacológico , Resultado del Tratamiento
12.
Ecotoxicol Environ Saf ; 238: 113592, 2022 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-35526452

RESUMEN

Surfactants are commonly used in detergents, soaps and agrichemical products. After use, the residual surfactants can be dispersed into environmental compartments, directly or indirectly affecting aquatic and terrestrial organisms. Ants are one of the few insects that are able to make and use tools when foraging for liquid food. However, this unique behavior of ants may be greatly affected by environmental pollutants. Here, we hypothesized that surfactants have adversarial impacts on ant foraging behavior, and tested this hypothesis by investigating the effect of TWEEN 80 (a common nonionic surfactant) on the tool use behavior of black imported fire ants (Solenopsis richteri) when foraging for liquid food (sugar water). Natural pine needles and man-made sponges were provided as tools for ants. The results revealed increasing surfactant concentration induced ants to deposit more tools and caused a higher drowning rate of ants. S. richteri tended to deposit more pine needles and tools of smaller size when exposed to surfactant. Interactions between tool type and surfactant concentration showed significant effects on tool deposition and drowning rate of ants. Addition of surfactant into sugar water increased the drowning rate and reduced the foraging activity and food collection of ant workers, suggesting that surfactant in liquid food can affect the foraging efficiency of ants. However, availability of tools reduced drowning rate and increased sugar water collected compared to without tools. Our results demonstrated that ants can adjust their tool use strategies to manage the foraging risk caused by environmental surfactant, such as increasing the amount and selecting appropriate size of the tools and assembling tools of different structures. Therefore, long-term exposure to surfactants may alter foraging behavior of ants and contribute to evolve new foraging strategy.


Asunto(s)
Hormigas , Ahogamiento , Comportamiento del Uso de la Herramienta , Animales , Hormigas/química , Conducta Alimentaria , Azúcares , Tensoactivos/toxicidad , Agua/farmacología
14.
Environ Pollut ; 287: 117359, 2021 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-34020258

RESUMEN

Ants are eusocial insects and have evolved sensitive chemosensory systems for social communication. However, the effect of heavy metal contamination on the olfactory sensitivity of ants remains largely unknown. Here, we investigated the survival and olfactory response of Solenopsis invicta under cadmium (Cd) exposure. As a result, exposure to dietary Cd at different concentrations (100, 300 and 500 mg/L) caused higher Cd accumulation and lower survival of the ants compared with the control (0 mg/L). Cd exposure induced diverse expression patterns of odor binding protein genes (SiOBPs) in S. invicta antenna. Specifically, the expression of SiOBP4, SiOBP11, SiOBP12 and SiOBP16 was increased by 1.84-, 1.14-, 0.83- and 1.76-fold, respectively, at 300 mg/L Cd, while SiOBP7 and SiOBP9 were suppressed as Cd concentration increased. Electroantennography (EAG) and behavioral bioassays were performed to further evaluate the effect of Cd contamination on the olfactory sensitivity of S. invicta workers to 2, 4, 6-trimethylpyridine (TMP) and 2-ethyl-3,6(5)-dimethylpyrazine (EDP), the two frequent functional semiochemicals for S. invicta. The results showed that under no Cd exposure, S. invicta workers exhibited strong EAG response and apparent residing repellence to TMP and EDP, but Cd exposure suppressed EAG response and deprived the behavioral repellence to TMP and EDP of the workers, suggesting that Cd exposure decreases the olfactory sensitivity of S. invicta to these two functional semiochemicals. Further fluorescence competitive binding assay revealed that SiOBP7 had strong binding affinity to TMP and EDP, suggesting that the decrease in olfactory sensitivity may be attributed to the inhibitory effect of Cd exposure on SiOBP7. Overall, our results suggest that Cd exposure may not only directly decrease the survival of ants, but also affect their olfactory recognition.


Asunto(s)
Hormigas , Repelentes de Insectos , Animales , Cadmio/toxicidad , Humanos , Feromonas
15.
Pest Manag Sci ; 77(6): 2843-2853, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33538389

RESUMEN

BACKGROUND: The invasive mealybug, Phenacoccus solenopsis, has caused serious damage to cotton crops throughout the world. Aenasius bambawalei is a dominant endoparasitoid of P. solenopsis. Exploration of behaviorally active semiochemicals may promote the efficacy of parasitoids used in biological control. Reverse chemical ecology, based on the physiological function of odorant-binding proteins (OBPs), provides an effective approach to screen behaviorally active compounds to target insect pests. Determination of the binding mechanisms and specificity towards different odorants in A. bambawalei may facilitate the development of more-efficient biological control strategies. RESULTS: We characterized the expression profile and analyzed the binding affinity of OBP28 in A. bambawalei. AbamOBP28 showed high expression in the wings and antennae of both male and female A. bambawalei. A fluorescence competitive binding assay indicated that AbamOBP28 displayed strong binding affinity to most candidate ligands. Circular dichroism spectra demonstrated that 1-octen-3-one, myrcene, dodecane, 2,4,4-trimethyl-2-pentene, nonanal, and limonene elicited conformational changes in AbamOBP28. Electrophysiological and behavioral bioassays revealed that diethyl sebacate, 2,4,4-trimethyl-2-pentene, and 1-octen-3-one evoked significant electroantennography responses and functioned as attractants in A. bambawalei at specific concentrations. Furthermore, three-dimensional structure modeling and molecular docking showed that hydrogen bonds were formed by Glu1 and Ser75 of AbamOBP28 with diethyl sebacate, respectively. CONCLUSION: These results demonstrate that AbamOBP28 is involved in the chemoreception of A. bambawalei. The identified protein provides a potential target for efficient enemy utilization and pest control, and the overall results may help develop protocols for more effective screening of behaviorally active semiochemicals. © 2021 Society of Chemical Industry.


Asunto(s)
Hormigas , Hemípteros , Receptores Odorantes , Animales , Femenino , Proteínas de Insectos/genética , Insectos , Masculino , Simulación del Acoplamiento Molecular , Feromonas/farmacología , Receptores Odorantes/genética
16.
Pest Manag Sci ; 77(3): 1371-1382, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33089649

RESUMEN

BACKGROUND: The red imported fire ant, Solenopsis invicta Buren, is one of the most successful invasive ants in the world. Previous studies indicated that benzyl acetate and prenyl acetate elicited significant electroantennography (EAG) response in S. invicta and exhibited as attractants at certain concentrations. In addition, the easy commercial availability, low cost, and low mammalian toxicity make acetate esters ideal candidates to screen for potential use in S. invicta control. RESULTS: We examined the EAG and behavioral responses to 26 acetate esters in all castes of S. invicta. Our results demonstrated a large diversity of EAG tuning and behavioral responses to acetate esters in S. invicta. For linear alkyl acetate esters, EAG response was clearly affected by the carbon chain length of the alkyl group. Linear alkyl acetates with five to seven carbon chain length of the alkyl group elicited significant EAG response in S. invicta, whereas those with shorter (C1 to C4) or longer (C8 to C12) carbon chain lengths did not. Different substitutions also exhibited large variety of EAG and behavioral responses in S. invicta. CONCLUSION: Our works explored the olfactory and behavioral response of S. invicta to structurally different acetate esters, and identified two potential fire ant attractants, pentyl acetate and tran-2-hexenyl acetate, and two potential repellents, hexyl acetate and cis-3-hexenyl acetate. These compounds may be useful in developing new products for fire ant management. Published 2020. This article is a U.S. Government work and is in the public domain in the USA.


Asunto(s)
Hormigas , Repelentes de Insectos , Acetatos , Animales , Conducta Animal , Ésteres
17.
Insects ; 11(2)2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-32024041

RESUMEN

Ant-hemipteran mutualism has been well documented, and many studies have reported the interference competition between ant species for the mutualism. However, little is known on how this interference competition impacts the reciprocally beneficial association. Previous studies demonstrated that the invasive mealybug Phenacoccus solenopsis (Tinsley) has established close mutual relationship with the ghost ant Tapinoma melanocephalum (Fabricius). The sympatric ants, Paratrechina longicornis (Latreille) and Tetramorium bicarinatum (Nylander) were frequently observed to compete for nutrient honeydew produced by P. solenopsis with T. melanocephalum. Herein, we investigated the effects of interference competition between the ant species on the ant-mealybug interactions. Phenacoccus solenopsis benefited from the tending by T. melanocephalum and P. longicornis. Interference competition between T. melanocephalum and P. longicornis interrupted the mutualism, suppressed the trailing activity of both species, but negligibly influenced the parasitism of Aenasius bambawalei Hayat, a solitary endoparasitoid of P. solenopsis. Harmonia axyridis, a predator of P. solenopsis, showed a significant avoidance when encountering with T. melanocephalum or P. longicornis, but not T. bicarinatum. Ant workers showed higher aggressiveness and lower exploratory activity when T. melanocephalum encountered P. longicornis. However, competition between T. melanocephalum and T. bicarinatum seldom influenced the trailing and exploratory activity of T. melanocephalum. It is concluded that interference competition for mutualism between ant species can mediate ant-mealybug associations and the fitness of mealybug colony. Our results also demonstrate that the effects of interference competition between ant species on ant-mealybug mutualism are varied among ant species.

18.
BMC Cardiovasc Disord ; 20(1): 15, 2020 01 13.
Artículo en Inglés | MEDLINE | ID: mdl-31931718

RESUMEN

BACKGROUND: Platelets in patients with type 2 diabetes mellitus (DM2) are characterized by increased activation and aggregation, which tends to be associated with a high morbidity and mortality due to cardiovascular disease (CVD). Moreover, a large proportion of DM2 patients show an inadequate response to standard antiplatelet treatments, contributing to recurrent cardiovascular events. In our previous study, we indicated that Salvianolic acid A (SAA) presents an antiplatelet effect in healthy volunteers. However, whether it can inhibit "activated platelets" with a pathologic status has not been explored. Therefore, this study was designed to investigate the antiplatelet effect of SAA and its diabetic complication-related difference in DM2. METHODS: Forty patients diagnosed with DM2 from January 2018 to April 2018 were recruited. Fibrinogen-binding (PAC-1) and P-selectin (CD62p) flow cytometry reagents were measured under resting and stimulated conditions by flow cytometry, while agonist-induced platelet aggregation was conducted by light transmission aggregometry. Before all these measurements were conducted, all platelet samples were preincubated with a vehicle or SAA for 10 min. Additionally, the diabetic complication-related difference in the antiplatelet effect of SAA was further studied in enrolled patients. RESULTS: The expressions of PAC-1 and CD62p were elevated in DM2, as well as the maximal platelet aggregation. In addition, SAA decreased the expressions of PAC-1 and CD62p, which were enhanced by ADP and thrombin (all P < 0.01). It also reduced the platelet aggregation induced by ADP (P < 0.001) and thrombin (P < 0.05). Comparing the antiplatelet effect of SAA on DM2, with and without diabetic complications, no statistically significant difference was found (all P > 0.05). CONCLUSIONS: The present study demonstrated that SAA can inhibit platelet activation and aggregation in patients with DM2, and the inhibition did not abate for the existence of diabetic complications.


Asunto(s)
Plaquetas/efectos de los fármacos , Ácidos Cafeicos/farmacología , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Lactatos/farmacología , Inhibidores de Agregación Plaquetaria/farmacología , Agregación Plaquetaria/efectos de los fármacos , Anciano , Biomarcadores/sangre , Plaquetas/metabolismo , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Selectina-P/sangre , Inhibidores de Agregación Plaquetaria/efectos adversos
19.
Biomed Res Int ; 2020: 2947067, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33490240

RESUMEN

Triglyceride-glucose index (TyG index) is associated with type 2 diabetes mellitus (T2DM), but research on this relationship is limited in Japan. The purpose of this study was to evaluate the correlation between TyG index and the risk of T2DM in the Japanese population. Here, 12732 participants were selected from the NAGALA study (NAfld in the Gifu Area, Longitudinal Analysis) conducted between 2004 and 2015 for a retrospective cohort analysis. The association between TyG index and T2DM was assessed using the Cox proportional-hazard model. Subgroup analyses were conducted according to age, sex, smoking status, alcohol consumption, waist circumference, BMI, and follow-up duration. The formula for TyG index was expressed as ln [fasting triglyceride level (mg/dL) × fasting plasma glucose level (mg/dL)/2]. After follow-up, 150 (1.18%) patients developed T2DM. After adjusting for potential confounders, a linear relationship was observed between TyG and the risk of T2DM. After adjusting for age, sex, BMI, waist circumference, HDL-cholesterol, total cholesterol, systolic blood pressure, regular exercise, smoking status, and alcohol consumption, TyG index, as a continuous variable, was associated with an increased risk of T2DM (adjusted hazard ratio (aHR), 1.79; 95% confidence interval (95% CI), 1.25-2.57). Compared with the first quartile of TyG index, subjects in the fourth quartile were 2.33-fold more likely to develop T2DM (aHR 2.33, 95% CI 1.09-4.96; P for trend 0.0224). Subgroup analyses showed that the association between TyG index and incident T2DM stably existed in different subgroups according to the variables tested. Therefore, TyG index was linearly related to the risk of incident T2DM in the Japanese population and may be used as a monitoring tool.


Asunto(s)
Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/epidemiología , Glucosa/análisis , Triglicéridos/sangre , Adulto , Femenino , Humanos , Japón/epidemiología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo
20.
Sci Rep ; 9(1): 13004, 2019 09 10.
Artículo en Inglés | MEDLINE | ID: mdl-31506506

RESUMEN

Mutualism between ants and honeydew producing hemipterans has been extensively studied. However, little is known on how ant-hemipteran mutualism impacts the co-occurring herbivores, which in turn affect the mutual relationship in ecosystems. Herein, we investigated the effect of ant-mealybug mutualism on the oviposition preference and spatial distribution of cotton leaf roller Sylepta derogata, a polyphagous herbivore, and in Apantetes derogatae performance, a larvae parasitoid of S. derogata. Leaf rollers constructed shelters for mealybugs to prevent them from enemy attack and preferred to lay eggs on plants with ant-mealybug mutualism. Egg abundance on mutualism-present plants was higher than on mutualism-absent plants. Leaf roller parasitoid A. derogatae showed higher parasitism on mutualism-absent plants. No obvious change in leaf roller egg abundance was observed when A. derogatae was excluded, suggesting that the parasitic pressure can also regulate the oviposition behavior of S. derogate. Apantetes derogatae showed higher aggressiveness in parasitizing leaf roller larvae at the absence of the mutualism. There was a definite correlation between leaf roller egg abundance and the number of patrolling ants on plants. Without ant-mealybug mutualism, S. derogata eggs showed a significantly aggregated distribution pattern, but a uniform distribution pattern was observed when the mutualism was present. Ant workers showed a consistently uniform distribution on plants. The results reveal a novel mediation effect of ant-mealybug association on the composition and structure of food webs in cotton field, which may contribute to a better understanding of the cascading effects of ant-hemipteran mutualism on other niche-related species in ecosystem.


Asunto(s)
Hormigas/fisiología , Hemípteros/fisiología , Herbivoria , Larva/fisiología , Hojas de la Planta/fisiología , Simbiosis , Animales , Ecosistema , Conducta Alimentaria , Cadena Alimentaria
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