Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 94
Filtrar
1.
Phytopathology ; 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38970801

RESUMEN

In this study, in planta assays were conducted to assess the effects of fungicide spray tactics, such as the reduction of the labeled fungicide dose and mixture with a multi-site fungicide, on fungicide resistance selection and disease control using Vitis vinifera 'Cabernet Sauvignon' grown in a greenhouse for two years. The entire clusters were inoculated with B. cinerea isolates at varying frequencies of fenhexamid resistance, followed by fungicide sprays, disease and fenhexamid resistance investigations at critical phenological stages. Our findings indicate that the lower dose of the at-risk fungicide, fenhexamid, effectively managed fenhexamid resistance and disease as well as the higher, labeled dose. In addition, mixture with the multi-site fungicide captan generally resulted a net-positive effect on both resistance management and disease control.

2.
Microbiol Spectr ; : e0026224, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38904374

RESUMEN

Salmonella enterica serovar Typhimurium is an important foodborne pathogen associated with human salmonellosis worldwide. A retrospective screening was performed to elucidate the prevalence, antimicrobial resistance, and phylogenomic characterization of this pathogen in Shanghai, China. S. Typhimurium isolates were selected from 2,211 serotyped Salmonella isolates collected during 2007-2019. Two hundred and seventy-seven S. Typhimurium isolates were detected in 15 of 16 districts in Shanghai. It was noted that 214 (77.3%) isolates were multi-drug resistant and 32 (11.6%) isolates were resistant to ciprofloxacin and 5 (1.8%) isolates were further resistant to ceftriaxone. Poisson generalized linear mixed model results showed that the multi-drug resistance (MDR) in 2017 and 2018 was significantly higher than that in 2010 (P<0.05), highlighting an increase in the risk of MDR. Phylogenetic results showed that a global data set of 401 sequenced S. Typhimurium isolates was classified into four clones (ST36, ST313, ST19, and ST34), which appeared in international clonal dissemination. The ST34 isolates from China fell into two clades, ST34C1 and ST34C2, the latter of which might originate from Shanghai, and then expanded nationally, accompanied by extended-spectrum ß-lactamase gene blaCTX-M-14 and a mutation in quinolone resistance-determining region of the gyrA 87 site. Furthermore, blaCTX-M-14 linking to ISEcp1 upstream and ΔIS903B downstream was found in IncI (Gamma)-like plasmids, and the plasmid conjugation contributed to its horizontal transmission. To our knowledge, it is the first report of the epidemiological and phylogenetic characterization for S. Typhimurium including the emerged clade ST34C2 in Shanghai, warranting the necessity of surveillance for this high-risk pathogen. IMPORTANCE: Our study uncovered a widespread distribution of Salmonella enterica serovar Typhimurium isolates in Shanghai accompanied by the increase in antimicrobial resistance (AMR) especially MDR during a 10-year period, which filled in the gap about a long period of continuous monitoring of AMR in this pathogen in Shanghai. Meanwhile, we identified a new clade ST34C2 of S. Typhimurium with the acquisition of IncI (Gamma)-like plasmids mediated by extended-spectrum ß-lactamase gene blaCTX-M-14 as well as gyrA 87 mutation, which had not been reported before. It was noted that IncI (Gamma)-like plasmids were reported in S. Typhimurium for the first time and conjugation could accelerate the spread of antimicrobial resistance gene blaCTX-M-14. These findings on the epidemic, antimicrobial resistance, and phylogenomic characterization for S. Typhimurium provide valuable insights into its potential risk to public health and also the basis for AMR prevention and control strategies in Shanghai in the future.

3.
J Med Case Rep ; 18(1): 123, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38515205

RESUMEN

BACKGROUND: Giant cell tumor of soft tissue is a low malignant uncommon neoplasm, with histologic features and immunophenotype similar to its bone counterpart. Primary giant cell tumor of soft tissue in the thyroid gland is considered an exceedingly rare entity. CASE PRESENTATION: We describe a case of primary thyroid giant cell tumor of soft tissue in a 69-year-old Chinese female patient. Neck ultrasonography showed a 19 mm × 12 mm × 5 mm nodule with heterogeneous echo and clear boundary located within the left thyroid. Histopathological examination revealed that the neoplasm was composed of two morphological components, mononuclear cells admixed with multinucleated osteoclast-like giant cells. Immunohistochemically, the tumor cells were positive for CD68 and vimentin, but were negative for epithelial membrane antigen, cytokeratin, and additional muscle markers. She underwent left unilateral thyroidectomy, and total thyroidectomy was performed for local recurrence 3 months later. The patient remained well without recurrence or metastasis following up for 12 months. CONCLUSION: The significance of this case lies in its rarity, the challenge of preoperative clinical diagnosis, and the differential diagnosis with other malignancies.


Asunto(s)
Tumores de Células Gigantes , Glándula Tiroides , Femenino , Humanos , Anciano , Glándula Tiroides/diagnóstico por imagen , Glándula Tiroides/patología , Tumores de Células Gigantes/diagnóstico , Cuello/patología , Tiroidectomía , Diagnóstico Diferencial
4.
Phytopathology ; 114(1): 137-145, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38318843

RESUMEN

Interactions between microorganisms and frugivorous insects can modulate fruit rot disease epidemiology. Insect feeding and/or oviposition wounds may create opportunities for fungal infection. Passive and active dispersal of fungal inoculums by adult insects also increases disease incidence. In fall-bearing raspberries and blackberries, such vectoring interactions could increase crop damage from the invasive pestiferous vinegar fly Drosophila suzukii (spotted-wing drosophila). Periods of peak D. suzukii activity are known to overlap with several species of primary fruit rot pathogen, particularly Botrytis cinerea and Cladosporium cladosporioides, and previous work indicates that larvae co-occur with and feed on various filamentous fungi at low rates. To further our understanding of the epidemiological consequences that may emerge from these associations, we surveyed the filamentous fungal community associated with adult D. suzukii, isolating and molecularly identifying fungi externally and internally (indicating feeding) from field-collected adults over 3 years. We isolated and identified 37 unique genera of fungi in total, including known raspberry pathogens. Most fungi were detected infrequently, and flies acquired and carried fungi externally at higher richness, frequency, and density relative to internally. In a worst-case scenario laboratory vectoring assay, D. suzukii adults were able to transfer B. cinerea and C. cladosporioides to sterile media at 0, 24, 48, and 72 h after exposure to sporulating cultures in Petri dishes. These results collectively suggest an adventitious vectoring association between D. suzukii and fruit rot fungi that has the potential to alter caneberry disease dynamics.


Asunto(s)
Drosophila , Rubus , Animales , Femenino , Enfermedades de las Plantas , Rubus/microbiología , Larva , Frutas/microbiología , Control de Insectos/métodos
5.
ACS Omega ; 9(6): 6888-6893, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38371768

RESUMEN

With climate change and environmental issues, the emissions of CO2 and its greenhouse effect have become a focal point. At present, the utilization of CO2 includes its synthesis into chemicals and fuels such as methane, methanol, and CO. CO2 utilization can be achieved through carbon capture and storage technologies, which involve capturing CO2 from industrial emissions and storing it to reduce the CO2 concentration in the atmosphere. However, these CO2 capture and utilization technologies still face challenges, such as technical immaturity and high costs. One of the CO2 capture and utilization technologies is the production of energy storage materials. In this study, CO2 captured by molten salt was used as the carbon source, and TiO2 nanotube arrays were used as precursors. Titanium carbide nanotube arrays(TiC-NTAs)with high specific surface area and high conductivity were prepared by electrolysis. Afterward, the electrochemical energy storage performance of TiC in different electrolytes was tested. The results show that reducing the ionic radius of the electrolyte is conducive to increasing the area-specific capacitance of the device and that the degradation of the cycle life of the quasi-solid supercapacitor may be caused by an increase in the internal resistance due to the loss of water from the electrolyte. This study provides a reference value for the low-temperature synthesis of nanometal carbides and the selection of electrolytes.

6.
Phytopathology ; 114(2): 368-377, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37606323

RESUMEN

Fungicide resistance is a limiting factor in sustainable crop production. General resistance management strategies such as rotation and mixtures of fungicides with different modes of action have been proven to be effective in many studies, but guidance on fungicide dose or application timing for resistance management remains unclear or debatable. In this study, Botrytis cinerea and the high-risk fungicide fenhexamid were used to determine the effects of fungicide dose, mixing partner, and application timing on resistance selection across varied frequencies of resistance via detached fruit assays. The results were largely consistent with the recent modeling studies that favored the use of the lowest effective fungicide dose for improved resistance management. In addition, even 10% resistant B. cinerea in the population led to about a 40% reduction of fenhexamid efficacy. Overall, our findings show that application of doses less than the fungicide label dose, mixture with the low-risk fungicide captan, and application postinfection seem to be the most effective management strategies in our controlled experimental settings. This somewhat contradicts the previous assumption that preventative sprays help resistance management.


Asunto(s)
Amidas , Botrytis , Fungicidas Industriales , Vitis , Captano/farmacología , Fungicidas Industriales/farmacología , Frutas , Enfermedades de las Plantas/prevención & control
7.
Plant Dis ; 108(6): 1526-1532, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38105460

RESUMEN

Two previously published ripe rot prediction models, DF2-NN and GH2-DT, were evaluated for fungicide application timing efficacy in Maryland vineyards. Both models utilize leaf wetness duration (LWD), temperature, and grape cluster phenological stages as model parameters. These three parameters were tracked throughout the 2021 to 2023 seasons in three vineyards. The fungicide efficacy trials started at the veraison phenological stage and included a nontreated control, a 12-day interval treatment, and two model-triggered treatments when risk predicted by the models crossed a threshold. The severity of ripe rot on the clusters in each treatment was assessed when the fruit were mature. Ripe rot severity in the nontreated controls was higher during seasons with more LWD and more precipitation. Days in which the models were triggered by the environmental conditions primarily coincided with precipitation events and lengthy LWDs. The model-triggered treatments never had significantly higher ripe rot severity than the 12-day interval treatment but had significantly lower severities than the nontreated control in most trials which had high ripe rot pressure. Furthermore, the model-triggered treatments resulted in fewer fungicide applications than the 12-day interval treatment on average. The DF2-NN model appeared to be more accurate and useful for ripe rot prediction and treatment than the GH2-DT model because it triggered fewer fungicide applications while reducing ripe rot. This model may be useful for improving or maintaining ripe rot control with fewer fungicide inputs, which may be beneficial for the environment and the reduction of fungicide resistance selection.


Asunto(s)
Colletotrichum , Fungicidas Industriales , Enfermedades de las Plantas , Vitis , Fungicidas Industriales/farmacología , Vitis/microbiología , Colletotrichum/efectos de los fármacos , Colletotrichum/fisiología , Enfermedades de las Plantas/prevención & control , Enfermedades de las Plantas/microbiología , Maryland , Frutas/microbiología , Estaciones del Año
8.
Front Plant Sci ; 14: 1278133, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38023927

RESUMEN

Introduction: Understanding fitness costs associated with fungicide resistance is critical to improve resistance management strategies. E198A in b-tubulin confers resistance to the fungicide thiophanate-methyl and has been widely reported in several plant pathogens including Colletotrichum siamense. Method: To better understand potential fitness costs associated with the resistance, a ribonucleoprotein (RNP) complex mediated CRISPR/Cas9 system was used to create a point mutation (E198A) through homology directed repair (HDR) in each of the sensitive (E198) C. siamense isolates collected from strawberries, raspberries, and peaches. The RNP complex was delivered into fungal protoplasts using polyethylene glycol-mediated (PEG) transfection. Results: The transformation efficiency, the proportion of transformants of sensitive parental isolates containing the E198A mutation, averaged 72%. No off-target mutations were observed when sequences similar to the b-tubulin target region with a maximum of four mismatch sites were analyzed, suggesting that the CRISPR/Cas9 system used in this study was highly specific for genome editing in C. siamense. Of the 41 comparisons of fitness between mutant and wild type isolates through in vitro and detached fruit assays, mutant isolates appeared to be as fit (24 of 41 comparisons), if not more fit than wild-type isolates (10 of 41 comparisons). Discussion: The use of CRISPR/Cas9 to evaluate fitness costs associated with point mutations in this study represents a novel and useful method, since wild-type and mutant isolates were genetically identical except for the target mutation.

9.
Materials (Basel) ; 16(17)2023 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-37687667

RESUMEN

Ultra-high Temperature Oxidation-Resistant Alloys (UTORAs) have received a lot of attention due to the increased research demand for deep space exploration around the world. However, UTORAs have the disadvantages of easy oxidation and chalking. So, in this study, a UTORAs is prepared by hot-press sintering on VZrHfNbTa (HEA: High Entropy Alloys can generally be defined as more than five elements by the equal atomic ratio or close to the equal atomic ratio alloying, the mixing entropy is higher than the melting entropy of the alloy, generally forming a high entropy solid solution phase of a class of alloys.) a substrate coated with hafnium. The bonding mechanism, resistance to high-temperature oxidation, and hardness of the sample tests are carried out. The results show that zirconium in the matrix will diffuse into the hafnium coating during the high-temperature sintering process and form the HfZr alloy transition layer, the coating thickness of the composite is about 120 µm, and the diffusion distance of zirconium in the hafnium coating is about 60 µm, this transition layer chemically combines the hafnium coating and the HEA substrate into a monolithic alloy composite. The results of high-temperature oxidation experiments show that the oxidation degree of the hafnium-coated VZrHfNbTa composite material is significantly lower than that of the VZrHfNbTa HEA after oxidation in air at 1600 °C for 5 h. The weight gain of the coated sample after oxidation is 56.56 mg/cm2, which is only 57.7% compared to the weight gain of the uncoated sample (98.09 mg/cm2 for uncoated), and the surface of the uncoated HEA shows obvious dents, oxidation, and pulverization occurred on the surface and interior of the sample. In contrast, the coated composite alloy sample mainly undergoes surface oxidation sintering to form a dense HfO2 protective layer, and the internal oxidation of the hafnium-coated VZrHfNbTa composite alloy is significantly lower than that of the uncoated VZrHfNbTa HEA.

10.
Langmuir ; 39(32): 11304-11316, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37535432

RESUMEN

Silane is known as an effective coating for enhancing the resistance of concrete to harmful acids and radicals that are usually produced by the metabolism of microorganisms. However, the mechanism of silane protection is still unclear due to its nanoscale attributes. Here, the protective behavior of silane on the calcium silicate hydrate (C-S-H) surface is examined under the attack environment of nitrate/sulfate ions using molecular dynamics simulations. The findings revealed that silane coating improved the resistance of C-S-H to nitrate/sulfate ions. This resistance is considered the origin of silane protection against harmful ion attacks. Further research on the details of molecular structures suggests that the interaction between the oxygen in the silane molecule and the calcium in C-S-H, which can prevent the coordination of sulfate and nitrate to calcium on the C-S-H surface, is the cause of the silane molecules' strong adsorption. These results are also proved in terms of free energy, which found that the adsorption free energy on the C-S-H surface followed the order silane > sulfate > nitrate. This research confirms the excellent protection performance of silane on the nanoscale. The revealed mechanism can be further used to help the development of high-performance composite coatings.

11.
mBio ; 14(3): e0339522, 2023 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-37184399

RESUMEN

The two-component system (TCS) PhoPQ has been demonstrated to be crucial for the formation of resistance to quinolones and cephalosporins in Salmonella Enteritidis (S. Enteritidis). However, the mechanism underlying PhoPQ-mediated antibiotic resistance formation remains poorly understood. Here, it was shown that PhoP transcriptionally regulated an assortment of genes associated with envelope homeostasis, the osmotic stress response, and the redox balance to confer resistance to quinolones and cephalosporins in S. Enteritidis. Specifically, cells lacking the PhoP regulator, under nalidixic acid and ceftazidime stress, bore a severely compromised membrane on the aspects of integrity, fluidity, and permeability, with deficiency to withstand osmolarity stress, an increased accumulation of intracellular reactive oxygen species, and dysregulated redox homeostasis, which are unfavorable for bacterial survival. The phosphorylated PhoP elicited transcriptional alterations of resistance-associated genes, including the outer membrane porin ompF and the aconitate hydratase acnA, by directly binding to their promoters, leading to a limited influx of antibiotics and a well-maintained intracellular metabolism. Importantly, it was demonstrated that the cavity of the PhoQ sensor domain bound to and sensed quinolones/cephalosporins via the crucial surrounding residues, as their mutations abrogated the binding and PhoQ autophosphorylation. This recognition mode promoted signal transduction that activated PhoP, thereby modulating the transcription of downstream genes to accommodate cells to antibiotic stress. These findings have revealed how bacteria employ a specific TCS to sense antibiotics and combat them, suggesting PhoPQ as a potential drug target with which to surmount S. Enteritidis. IMPORTANCE The prevalence of quinolone and cephalosporin-resistant S. Enteritidis is of increasing clinical concern. Thus, it is imperative to identify novel therapeutic targets with which to treat S. Enteritidis-associated infections. The PhoPQ two-component system is conserved across a variety of Gram-negative pathogens, by which bacteria adapt to a range of environmental stimuli. Our earlier work has demonstrated the importance of PhoPQ in the resistance formation in S. Enteritidis to quinolones and cephalosporins. In the current work, we identified a global profile of genes that are regulated by PhoP under antibiotic stresses, with a focus on how PhoP regulated downstream genes, either positively or negatively. Additionally, we established that PhoQ sensed quinolones and cephalosporins in a manner of directly binding to them. These identified genes and pathways that are mediated by PhoPQ represent promising targets for the development of a drug potentiator with which to neutralize antibiotic resistance in S. Enteritidis.


Asunto(s)
Quinolonas , Salmonella enteritidis , Salmonella enteritidis/genética , Salmonella enteritidis/metabolismo , Transcripción Genética , Quinolonas/farmacología , Resistencia a las Cefalosporinas , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Antibacterianos/farmacología , Cefalosporinas/farmacología , Regulación Bacteriana de la Expresión Génica
12.
Plant Dis ; 107(10): 2929-2934, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37005504

RESUMEN

Fungal pathogens continue to pose a significant threat to grape production. Previous studies of pathogens associated with late-season bunch rots in Mid-Atlantic vineyards had elucidated the primary causal agents of these diseases, but the significance and identity of the less commonly isolated genera was unclear. Therefore, to more fully understand the identity and pathogenicity of Cladosporium, Fusarium, and Diaporthe spp. associated with late-season bunch rots of wine grapes in the Mid-Atlantic, phylogenic analyses and pathogenicity assays were conducted. Isolates were characterized to the species level by sequencing the TEF1 and Actin, TEF1 and TUB2, and TEF1 genes for 10, 7, and 9 isolates of Cladosporium, Diaporthe, and Fusarium, respectively. Four Cladosporium, three Fusarium, and three Diaporthe species were identified, and C. allicinum, C. perangustum, C. pseudocladosporioides, F. graminearum, and D. guangxiensis had not yet been isolated from grape in North America. The pathogenicity of each species was evaluated on detached table and wine grapes, and D. eres, D. ampelina, D. guangxiensis, and F. fujikuroi were found to be the most aggressive on both table and wine grapes. Further investigations through more extensive isolate collection and of myotoxicity testing may be warranted due to the prevalence and pathogenicity of D. eres and F. fujikuroi.


Asunto(s)
Fusarium , Saccharomycetales , Vitis , Vitis/microbiología , Fusarium/genética , Cladosporium , Virulencia , Estaciones del Año
13.
J Med Case Rep ; 17(1): 182, 2023 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-37076922

RESUMEN

BACKGROUND: Fumarate hydratase-deficient renal cell carcinoma is a rare pathological subtype that was defined by the World Health Organization (WHO 5th edition) in 2022. At present, only a few hundreds of cases have been reported worldwide, mainly in Europe and the United States. A case of a Chinese patient is reported here, along with a literature review. CASE REPORT: A 60-year-old Asian male who complained of hematuria for 20 days was admitted to the hospital. Contrast enhanced Computer Tomography showed that the volume of the right kidney was increased, with a patchy low-density shadow with infiltrative growth inside that had a significantly lower signal intensity than the renal cortex; thus, the possibility of collecting duct carcinoma or lymphoma, was considered. Enlarged perirenal and retroperitoneal lymph nodes were also seen, along with bilateral renal cysts. Eight years prior, ultrasonography had shown a complex renal cyst in the right kidney, and no treatment was administered at that time. Laparoscopic radical nephrectomy of the right kidney was performed this time, and the postoperative specimens were submitted for pathological examination. Because immunohistochemistry showed the loss of fumarate hydratase protein expression and the possibility of fumarate hydratase-deficient renal cell carcinoma was considered, corresponding molecular pathological tests were performed, and the results showed an FHp.R233H (arginine > histidine) germline mutation (inactivation mutation). The postoperative pathological diagnosis was fumarate hydratase-deficient renal cell carcinoma in the right kidney, T3aN1M0. The patient was treated with sunitinib, and bone and liver metastases developed half a year later. The treatment was then changed to axitinib and toripalimab. At present, the patient is in stable condition, and there has been no progression of the metastases. CONCLUSION: Fumarate hydratase-deficient renal cell carcinoma is a very rare renal tumor that is defined on a molecular basis. It is highly malignant and metastasizes early. Therefore, fully understanding the disease, enabling detection and diagnosis and administering treatment are particularly important.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Masculino , Humanos , Persona de Mediana Edad , Carcinoma de Células Renales/patología , Fumarato Hidratasa/genética , Neoplasias Renales/patología , Riñón/patología , Mutación de Línea Germinal
14.
Artículo en Inglés | MEDLINE | ID: mdl-36981923

RESUMEN

Floodplains have important ecological and hydrological functions in terrestrial ecosystems, experience severe soil erosion, and are vulnerable to losing soil fertility. Tamarix chinensis Lour. plantation is the main vegetation restoration measure for maintaining soil quality in floodplains. Soil microorganisms are essential for driving biogeochemical cycling processes. However, the effects of sampling location and shrub patch size on soil microbial community composition remain unclear. In this study, we characterized changes in microbial structure, as well as the factors driving them, in inside- and outside-canopy soils of three patch sizes (small, medium, large) of T. chinensis plants in the middle Yellow River floodplain. Compared with the outside-canopy soils, inside-canopy had higher microbial phospholipid fatty acids (PLFAs), including fungi, bacteria, Gram-positive bacteria (GP), Gram-negative bacteria (GN), and arbuscular mycorrhizal fungi. The ratio of fungi to bacteria and GP to GN gradually decreased as shrub patch size increased. Differences between inside-canopy and outside-canopy soils in soil nutrients (organic matter, total nitrogen, and available phosphorus) and soil salt content increased by 59.73%, 40.75%, 34.41%, and 110.08% from small to large shrub patch size. Changes in microbial community composition were mainly driven by variation in soil organic matter, which accounted for 61.90% of the variation in inside-canopy soils. Resource islands could alter microbial community structure, and this effect was stronger when shrub patch size was large. The results indicated that T. chinensis plantations enhanced the soil nutrient contents (organic matter, total nitrogen, and available phosphorus) and elevated soil microbial biomass and changed microbial community composition; T. chinensis plantations might thus provide a suitable approach for restoring degraded floodplain ecosystems.


Asunto(s)
Micorrizas , Tamaricaceae , Suelo/química , Ecosistema , Ríos , Microbiología del Suelo , Bacterias , Nitrógeno/análisis , Fósforo , China
15.
J Agric Food Chem ; 71(2): 1214-1223, 2023 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-36602420

RESUMEN

The structure of allergenic proteins provides important information about the binding of allergens to antibodies. In this study, the crystal structure of Scy p 4 with a resolution of 1.60 Å was obtained by X-ray diffraction. Epitope mapping of Scy p 4 revealed that linear epitopes are located on the surface of Scy p 4. Also, conformational epitopes are mostly located in the structural conservative region. Further structural comparison, surface electrostatic potential, and hydrogen bond force analysis showed that mutation of Asp70 and Asp18/20/70 would lead to calcium-binding capacity being lost and destruction of allergenicity. Furthermore, a comparative analysis of structure showed that sarcoplasmic-calcium-binding protein (SCP) had high sequence, secondary, and spatial structural identity in crustaceans, which may be an important factor leading to cross-reactivity among crustaceans. The structure of Scy p 4 provides a template for epitope evaluation and localization of SCPs, which will help to reveal cross-reactivity among species.


Asunto(s)
Alérgenos , Braquiuros , Animales , Alérgenos/química , Secuencia de Aminoácidos , Proteínas de Unión al Calcio/química , Inmunoglobulina E , Braquiuros/genética , Epítopos/química
16.
J Clin Pathol ; 77(1): 61-67, 2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-36319076

RESUMEN

PURPOSE: Programmed cell death-ligand 1 (PD-L1) as a cell surface glycoprotein can inhibit T cell function when binding to its receptor, PD-1. The newly developed therapy of targeting PD-1/PD-L1 signal pathway has shown great promise for the treatment of non-small cell lung cancer as well as melanoma. Approved by Food and Drug Administration, atezolizumab has become the first new drug to treat advanced bladder cancer. The aim of this study is to evaluate whether PD-L1 is associated with the lymphocytes infiltration in the tumour microenvironment and to assess the prognostic value of PD-L1 expression. MATERIALS AND METHODS: Among 96 invasive bladder urothelial carcinomas, some were used to construct tissue-microarrays, and some cases with shallow infiltration or large heterogeneity were performed, respectively, for the following work. By means of immunohistochemistry and HE, PD-L1 expression and immune cell infiltration in the invasive front of urothelial carcinoma were analysed. RESULTS: We find that PD-L1 expression in tumour cells and lymphocytes are significantly associated with more tumour infiltrating lymphocytes (TILs) and more T cells. The integrated TILs, T-PD-L1 and I-PD-L1 are not significantly correlated with the overall survival (OS) of patients. However, the combination of T-PD-L1 and TILs, T-PD-L1 and I-PD-L1 is significantly correlated with the OS of patients. The T-PD-L1 (-)/TIL (-) group show the best prognosis and the T-PD-L1 (+)/I-PD-L1 (-) group show the worst prognosis. Furthermore, a multivariate analysis reveal that PD-L1 expression of lymphocytes is an independent prognostic factor for OS of patients. CONCLUSIONS: Our study reveal that PD-L1 of tumour cells are associated with the corresponding T cells infiltration and that the combination of T-PD-L1 and I-PD-L1, T-PD-L1 and TILs could be a relevant marker for the determination of the prognostic role of patients with the urothelial carcinoma.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Carcinoma de Células Transicionales , Neoplasias Pulmonares , Neoplasias de la Vejiga Urinaria , Humanos , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Células Transicionales/patología , Neoplasias de la Vejiga Urinaria/patología , Antígeno B7-H1/metabolismo , Neoplasias Pulmonares/patología , Estimación de Kaplan-Meier , Pronóstico , Linfocitos Infiltrantes de Tumor , Linfocitos T CD8-positivos , Microambiente Tumoral
17.
Pestic Biochem Physiol ; 188: 105227, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36464347

RESUMEN

Due to recent evidence of Aspergillus uvarum pathogenicity on wine grapes and variable fungicide sensitivity to quinone outside inhibitor (QoI) fungicides, the identity and QoI sensitivity of Aspergillus isolates from the Mid-Atlantic United States was investigated. Phylogenic analysis of 31 isolates revealed 26 as A. uvarum and 5 as A. japonicus, both of which have been previously isolated from grape. The A. uvarum isolates had variable sensitivities to the QoI azoxystrobin, and the genomic region that codes for the target of QoIs, cytochrome b, was sequenced. Translation of the cytochrome b coding sequence revealed that the most resistant isolates (termed cytb3) contained three mutations, S108A, F129L, and A194V, and the moderately sensitive isolates (termed cytb2) contained two mutations S108A and A194V. This is the first report of an amino acid variation in cytochrome b at position 108. Cytb3 isolates were significantly less inhibited than the cytb2 and wild-type isolates (cytbWT) in vitro, and were significantly less inhibited than the cytbWT isolates on detached fruit. Molecular docking analysis revealed similar differences, with azoxystrobin binding most securely in the cytbWT variant of cytochrome b than cytb2 and cytb3. As Aspergillus rot has not been a target disease of fungicide sprays in the U.S., the selection of resistant phenotypes is likely resultant from sprays for other diseases. Resistance is of concern due to the pathogenicity of A. uvarum and A. japonicus on wine grapes, and the ability of these species to be mycotoxigenic or pathogenic for humans.


Asunto(s)
Fungicidas Industriales , Vitis , Humanos , Estaciones del Año , Citocromos b/genética , Simulación del Acoplamiento Molecular , Aspergillus/genética , Fungicidas Industriales/farmacología , Quinonas
18.
Front Oncol ; 12: 982807, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36263227

RESUMEN

Background: Surgical resection is still the primary way to treat gastric cancer. Therefore, postoperative complications such as IAI (intra-abdominal infection) are major problems that front-line clinical workers should pay special attention to. This article was to build and validate IAI's RF (regression function) model. Furthermore, it analyzed the prognosis in patients with IAI after surgery for stomach cancer. The above two points are our advantages, which were not involved in previous studies. Methods: The data of this study was divided into two parts, the training data set and the validation data set. The training data for this article were from the patients treated surgically with gastric cancer in our center from December 2015 to February 2017. We examined IAI's morbidity, etiological characteristics, and prognosis in the training data set. Univariate and multivariate logistic regression analyses were used to screen risk factors, establish an RF model and create a nomogram. Data from January to March 2021 were used to validate the accuracy of the RF model. Results: The incidence of IAI was 7.2%. The independent risk factors for IAI were hypertension (Odds Ratio [OR] = 3.408, P = 0.001), history of abdominal surgery (OR = 2.609, P = 0.041), combined organ excision (OR = 4.123, P = 0.010), and operation time ≥240 min (OR = 3.091, P = 0.005). In the training data set and validation data set, the area under the ROC curve of IAI predicted by the RF model was 0.745 ± 0.048 (P<0.001) and 0.736 ± 0.069 (P=0.003), respectively. In addition, IAI significantly extended the length of hospital stay but had little impact on survival. Conclusions: Patients with hypertension, combined organ excision, a history of abdominal surgery, and a surgical duration of 240 min or more are prone to IAI, and the RF model may help to identify them.

19.
mSphere ; 7(6): e0038322, 2022 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-36286534

RESUMEN

The two-component system (TCS) is one of the primary pathways by which bacteria adapt to environmental stresses such as antibiotics. This study aimed to systematically explore the role of TCSs in the development of multidrug resistance (MDR) in Salmonella enterica serovar Enteritidis. Twenty-six in-frame deletion mutants of TCSs were generated from S. Enteritidis SJTUF12367 (the wild type [WT]). Antimicrobial susceptibility tests with these mutants revealed that 10 TCSs were involved in the development of antibiotic resistance in S. Enteritidis. In these 10 pairs of TCSs, functional defects in CpxAR, PhoPQ, and GlnGL in various S. Enteritidis isolates led to a frequent decrease in MIC values against at least three classes of clinically important antibiotics, including cephalosporins and quinolones, which indicated the importance of these TCSs to the formation of MDR. Interaction network analysis via STRING revealed that the genes cpxA, cpxR, phoP, and phoQ played important roles in the direct interaction with global regulatory genes and the relevant genes of efflux pumps and outer membrane porins. Quantitative reverse transcription-PCR analysis further demonstrated that the increased susceptibility to cephalosporins and quinolones in ΔphoP and ΔcpxR mutant cells was accompanied by increased expression of membrane porin genes (ompC, ompD, and ompF) and reduced expression of efflux pump genes (acrA, macB, and mdtK), as well as an adverse transcription of the global regulatory genes (ramA and crp). These results indicated that CpxAR and PhoPQ played an important role in the development of MDR in S. Enteritidis through regulation of cell membrane permeability and efflux pump activity. IMPORTANCE S. Enteritidis is a predominant Salmonella serotype that causes human salmonellosis and frequently exhibits high-level resistance to commonly used antibiotics, including cephalosporins and quinolones. Although TCSs are known as regulators for bacterial adaptation to stressful conditions, which modulates ß-lactam resistance in Vibrio parahaemolyticus and colistin resistance in Salmonella enterica serovar Typhimurium, there is little knowledge of their functional mechanisms underlying the development of antibiotic resistance in S. Enteritidis. Here, we systematically identified the TCS elements in S. Enteritidis SJTUF12367, revealed that the three TCSs CpxAR, PhoPQ, and GlnGL were crucial for the MDR formation in S. Enteritidis, and preliminarily illustrated the regulatory functions of CpxAR and PhoPQ for antimicrobial resistance genes. Our work provides the basis to understand the important TCSs that regulate formation of antibiotic resistance in S. Enteritidis.


Asunto(s)
Antiinfecciosos , Quinolonas , Humanos , Salmonella enteritidis/genética , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Antibacterianos/metabolismo , Antiinfecciosos/farmacología , Salmonella typhimurium/metabolismo , Farmacorresistencia Bacteriana Múltiple/genética , Cefalosporinas , Quinolonas/farmacología , Quinolonas/metabolismo
20.
Org Lett ; 24(28): 5056-5061, 2022 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-35816096

RESUMEN

An efficient Tf2NH-catalyzed [2 + 2] cycloaddition of ynamides under mild conditions has been developed. Within short reaction times, various ynamides are transformed into the corresponding 3-aminocyclobutenones in good to excellent yields. This is the first example for the metal-free intermolecular [2 + 2] self-cycloaddition of ynamides. Meanwhile, the desired cycloaddition products can be easily transformed into aminonaphthol derivatives.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...