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1.
Curr Microbiol ; 81(5): 134, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38592513

RESUMO

A novel Paracoccus-related strain, designated YLB-12T, was isolated from a sediment sample from the tidal zone of Shapowei Port, Xiamen, Fujian Province, PR China. The novel strain is a Gram-stain-negative, short, rod-shaped, nonmotile, catalase- and oxidase-positive strain that grows at 10-37 °C and pH 5.0-9.0 in the presence of 0-12.0% (w/v) NaCl. Phylogenetic analysis of the 16S rRNA gene sequences indicated that this strain belongs to the genus Paracoccus and that its highest sequence similarity was to Paracoccus homiensis DD-R11T (98.5%), followed by Paracoccus zeaxanthinifaciens ATCC 21588T (97.4%), Paracoccus rhizosphaerae LMG 26205T (97.2%), Paracoccus beibuensis CGMCC 1.7295T (97.1%) and Paracoccus halotolerans CFH 90064T (97.0%). The DNA‒DNA hybridization values between strain YLB-12T and the five closely related type strains ranged from 20.4 to 22.4%. The genomic G+C content of strain YLB-12T was 63.7%. In addition to diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine and phosphatidylglycerol, the polar lipids of the strain YLB-12T also consisted of an unidentified glycolipid and four unidentified polar lipids. The cells contained summed feature 8 (C18: 1ω6c /C18: 1ω7c, 62.7%) as the major cellular fatty acid and ubiquinone-10 as the predominant menaquinone. On the basis of its phenotypic and genotypic characteristics, strain YLB-12T represents a novel species within the genus Paracoccus, for which the name Paracoccus maritimus sp. nov. is proposed. The type strain was YLB-12T (= MCCC 1A17213T = KCTC 82197T).


Assuntos
Ácidos Graxos , Paracoccus , Filogenia , RNA Ribossômico 16S/genética , Paracoccus/genética , DNA
2.
BMC Anesthesiol ; 24(1): 56, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38331767

RESUMO

OBJECTIVES: Although several independent risk factors for postoperative pulmonary complications (PPCs) after spinal tumor surgery have been studied, a simple and valid predictive model for PPC occurrence after spinal tumor surgery has not been developed. PATIENTS AND METHODS: We collected data from patients who underwent elective spine surgery for a spinal tumor between 2013 and 2020 at a tertiary hospital in China. Data on patient characteristics, comorbidities, preoperative examinations, intraoperative variables, and clinical outcomes were collected. We used univariable and multivariable logistic regression models to assess predictors of PPCs and developed and validated a nomogram for PPCs. We evaluated the performance of the nomogram using the area under the receiver operating characteristic curve (ROC), calibration curves, the Brier Score, and the Hosmer-Lemeshow (H-L) goodness-of-fit test. For clinical use, decision curve analysis (DCA) was conducted to identify the model's performance as a tool for supporting decision-making. RESULTS: Among the participants, 61 (12.4%) individuals developed PPCs. Clinically significant variables associated with PPCs after spinal tumor surgery included BMI, tumor location, blood transfusion, and the amount of blood lost. The nomogram incorporating these factors showed a concordance index (C-index) of 0.755 (95% CI: 0.688-0.822). On internal validation, bootstrapping with 1000 resamples yielded a bias-corrected area under the receiver operating characteristic curve of 0.733, indicating the satisfactory performance of the nomogram in predicting PPCs. The calibration curve demonstrated accurate predictions of observed values. The decision curve analysis (DCA) indicated a positive net benefit for the nomogram across most predicted threshold probabilities. CONCLUSIONS: We have developed a new nomogram for predicting PPCs in patients who undergo spinal tumor surgery.


Assuntos
Neoplasias da Coluna Vertebral , Humanos , Neoplasias da Coluna Vertebral/cirurgia , Nomogramas , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Procedimentos Neurocirúrgicos , China , Estudos Retrospectivos
3.
Mar Genomics ; 73: 101087, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38365347

RESUMO

Tobacco bacterial wilt (TBW) caused by Ralstonia solanacearum is a serious soil-borne disease, which seriously damages the growth of tobacco crops. Bacillus velezensis A5 was isolated from 3000 m deep-sea sediments of the Pacific Ocean, and was found to be antagonistic to TBW. Here, we report the complete genome sequence of strain A5, which has a 4,000,699-bp single circular chromosome with 3827 genes and a G + C content of 46.44%, 87 tRNAs, and 27 rRNAs. A total of 12 gene clusters were identified in the genome of strain A5, which were responsible for the biosynthesis of antibacterial compounds, including surfactin, bacillaene, fengycin, difficidin, bacillibactin, and bacilysin. Additionally, strain A5 was found to contain a series of genes related to the biosynthesis of carbohydrate-active enzymes and secreted proteins. Our results indicate that strain A5 can be considered a promising biocontrol agent against TBW in agricultural fields.


Assuntos
Bacillus , Genoma Bacteriano , Oceano Pacífico , Bacillus/genética , Bacillus/metabolismo , Bactérias/genética , Análise de Sequência
4.
J Agric Food Chem ; 72(6): 2989-2996, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38214488

RESUMO

The bacterial wilt caused by Ralstonia solanacearum seriously affects crop yield and safety and is difficult to control. Biological activity-guided screening led to the isolation of 11 phenolic compounds including three undescribed compounds (carnemycin H-I and stromemycin B) from the secondary metabolites of a marine-derived Aspergillus ustus. One new compound is an unusual phenolic dimer. Their structures were elucidated by comprehensive spectroscopic data and J-based configurational analysis. The antibacterial activities of the isolated compounds against R. solanacearum were evaluated. Compound 3 exhibited excellent inhibitory activity with an MIC value of 3 µg/mL, which was comparable to that of streptomycin sulfate. Additionally, 3 significantly changed the morphology and inhibited the activity of succinate dehydrogenase (SDH) to interfere with the growth of R. solanacearum. Molecular docking was conducted to clarify the potential mechanisms of compound 3 with SDH. Further in vivo experiments demonstrated that 3 could remarkably inhibit the occurrence of bacterial wilt on tomatoes.


Assuntos
Antibacterianos , Aspergillus , Ralstonia solanacearum , Antibacterianos/farmacologia , Antibacterianos/química , Simulação de Acoplamento Molecular , Fenóis/farmacologia , Bactérias , Fungos , Doenças das Plantas/microbiologia
5.
Mar Genomics ; 72: 101071, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38008533

RESUMO

Bacillus species have been considered as promising biological control agents due to their excellent antimicrobial ability. Bacillus cereus strain Z4 was isolated from 2000 m deep sea sediments of the Western Pacific Ocean, which possesses significant antifungal activity against Phytophthora nicotianae, the pathogenic fungus of tobacco black shank disease. To reveal the underlying antifungal genetic mechanisms, here, we report the complete genomic sequence of the strain Z4. The genome has one circular chromosome of 5,664,309 bp with a G + C content of 35.31%, 109 tRNAs, and 43 rRNAs. Genomic analysis identified 10 gene clusters related to the biosynthesis of biocontrol active compounds, including bacillibactin, petrobactin, fengycin, and molybdenum cofactor. Meanwhile, 6 gene clusters were responsible for the biosynthesis of metabolites with unknown functions. Strain Z4 also contains a large number of genes encoding carbohydrate-active enzymes and secreted proteins, respectively. The whole genomic analysis of Bacillus cereus Z4 may provide a valuable reference for elucidating its biocontrol mechanism against tobacco black shank.


Assuntos
Bacillus cereus , Bacillus , Bacillus cereus/genética , Bacillus cereus/metabolismo , Antifúngicos/metabolismo , /metabolismo , Oceano Pacífico , Bacillus/genética
6.
Clin Appl Thromb Hemost ; 29: 10760296231209927, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37933155

RESUMO

Hemostatic disturbances after cardiac surgery can lead to excessive postoperative bleeding. Thromboelastography (TEG) was employed to evaluate perioperative coagulative alterations in patients undergoing cardiac surgery with cardiopulmonary bypass (CPB), investigating the correlation between factors concomitant with cardiac surgery and modifications in coagulation. Coagulation index as determined by TEG correlated significantly with postoperative bleeding at 24-72 h after cardiac surgery (P < .001). Among patients with a normal preoperative coagulation index, those with postoperative hypocoagulability showed significantly lower nadir temperature (P = .003), larger infused fluid volume (P = .003), and longer CPB duration (P = .033) than those with normal coagulation index. Multivariate logistic regression showed that nadir intraoperative temperature was an independent predictor of postoperative hypocoagulability (adjusted OR: 0.772, 95% CI: 0.624-0.954, P = .017). Multivariate linear regression demonstrated linear associations of nadir intraoperative temperature (P = .017) and infused fluid volume (P = .005) with change in coagulation index as a result of cardiac surgery. Patients are susceptible to hypocoagulability after cardiac surgery, which can lead to increased postoperative bleeding. Ensuring appropriate temperature and fluid volume during cardiac surgery involving CPB may reduce risk of postoperative hypocoagulability and bleeding.


Assuntos
Coagulação Sanguínea , Procedimentos Cirúrgicos Cardíacos , Humanos , Estudos Retrospectivos , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Tromboelastografia , Hemorragia Pós-Operatória/etiologia , Fatores de Risco , Ponte Cardiopulmonar/efeitos adversos
7.
Global Spine J ; : 21925682231212860, 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37918436

RESUMO

STUDY DESIGN: Retrospective case-control study. OBJECTIVE: To explore the association of early postoperative nadir hemoglobin with risk of a composite outcome of anemia-related and other adverse events. METHODS: We retrospectively analyzed data from spinal tumor patients who received intraoperative blood transfusion between September 1, 2013 and December 31, 2020. Uni- and multivariate logistic regression was used to explore relationships of clinicodemographic and surgical factors with risk of composite in-hospital adverse events, including death. Subgroup analysis explored the relationship between early postoperative nadir hemoglobin and composite adverse events. RESULTS: Among the 345 patients, 331 (95.9%) experienced early postoperative anemia and 69 (20%) experienced postoperative composite adverse events. Multivariate logistic regression analysis showed that postoperative nadir Hb (OR = .818, 95% CI: .672-.995, P = .044), ASA ≥3 (OR = 2.007, 95% CI: 1.086-3.707, P = .026), intraoperative RBC infusion volume (OR = 1.133, 95% CI: 1.009-1.272, P = .035), abnormal hypertension (OR = 2.199, 95% CI: 1.085-4.457, P = .029) were correlated with composite adverse events. The lumbar spinal tumor was associated with composite adverse events with a decreased odds compared to thoracic spinal tumors (OR = .444, 95% CI: .226-.876, P = .019). Compared to patients with postoperative nadir hemoglobin ≥11.0 g/dL, those with nadir <9.0 g/dL were at significantly higher risk of postoperative composite adverse events (OR = 2.709, 95% CI: 1.087-6.754, P = .032). CONCLUSION: Nadir hemoglobin <9.0 g/dL after spinal tumor surgery is associated with greater risk of postoperative composite adverse events in patients who receive intraoperative blood transfusion.

8.
Ren Fail ; 45(2): 2261552, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37782276

RESUMO

BACKGROUND: Circular RNAs (circRNAs) are promising biomarkers and therapeutic targets for acute kidney injury (AKI). In this study, we investigated the mechanism by which circRNA itchy E3 ubiquitin protein ligase (circ-ITCH) regulates sepsis-induced AKI. METHODS: A sepsis-induced AKI mouse model was created using LPS induction and circ-ITCH overexpression. Circ-ITCH levels were confirmed via RT-qPCR. Kidney tissue changes were examined through various stains and TUNEL. Enzyme-linked immunosorbent assay (ELISA) gauged oxidative stress and inflammation. Mitochondrial features were studied with electron microscopy. RT-qPCR and western blotting assessed mitochondrial function parameters. Using starBase, binding sites between circ-ITCH and miR-214-3p, as well as miR-214-3p and ABCA1, were predicted. Regulatory connections were proven by dual-luciferase assay, RT-qPCR, and western blotting. RESULTS: Circ-ITCH expression was downregulated in LPS-induced sepsis mice. Overexpression of circ-ITCH ameliorates indicators of renal function (serum creatinine [SCr], blood urea nitrogen [BUN], neutrophil gelatinase-associated lipocalin [NGAL], and kidney injury molecule-1 [Kim-1]), reduces renal cell apoptosis, mitigates oxidative stress markers (reactive oxygen species [ROS] and malondialdehyde [MDA]), and diminishes inflammatory markers (interleukin [IL]-1ß, IL-6, and tumor necrosis factor [TNF-α]). Moreover, circ-ITCH overexpression alleviated mitochondrial damage and dysfunction. Furthermore, circ-ITCH acts as a sponge for miR-214-3p, thereby upregulating ABCA1 expression. In addition, the miR-214-3p inhibitor repressed oxidative stress, inflammation, and mitochondrial dysfunction, which was reversed by circ-ITCH knockdown. Further cellular analysis in HK-2 cells supported these findings, highlighting the protective role of circ-ITCH against sepsis-induced AKI, particularly through the miR-214-3p/ABCA1 axis. CONCLUSION: The novel circ-ITCH/miR-214-3p/ABCA1 pathway plays an essential role in the regulation of oxidative stress and mitochondrial dysfunction in sepsis-induced AKI.


Assuntos
Injúria Renal Aguda , MicroRNAs , Sepse , Animais , Camundongos , RNA Circular/genética , Lipopolissacarídeos , Injúria Renal Aguda/genética , Sepse/complicações , Apoptose , Trifosfato de Adenosina
9.
Front Public Health ; 11: 1188246, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37397759

RESUMO

Background: Observational studies have suggested an association between obesity and iron deficiency anemia, but such studies are susceptible to reverse causation and residual confounding. Here we used Mendelian randomization to assess whether the association might be causal. Methods: Data on single-nucleotide polymorphisms that might be associated with various anthropometric indicators of obesity were extracted as instrumental variables from genome-wide association studies in the UK Biobank. Data on genetic variants in iron deficiency anemia were extracted from a genome-wide association study dataset within the Biobank. Heterogeneity in the data was assessed using inverse variance-weighted regression, Mendelian randomization Egger regression, and Cochran's Q statistic. Potential causality was assessed using inverse variance-weighted, Mendelian randomization Egger, weighted median, maximum likelihood and penalized weighted median methods. Outlier SNPs were identified using Mendelian randomization PRESSO analysis and "leave-one-out" analysis. Results: Inverse variance-weighted regression associated iron deficiency anemia with body mass index, waist circumference, trunk fat mass, body fat mass, trunk fat percentage, and body fat percentage (all odds ratios 1.003-1.004, P ≤ 0.001). Heterogeneity was minimal and no evidence of horizontal pleiotropy was found. Conclusion: Our Mendelian randomization analysis suggests that obesity can cause iron deficiency anemia.


Assuntos
Anemia Ferropriva , Humanos , Anemia Ferropriva/complicações , Anemia Ferropriva/epidemiologia , Anemia Ferropriva/genética , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Obesidade/complicações , Obesidade/genética , Antropometria
10.
Toxins (Basel) ; 15(7)2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-37505709

RESUMO

Venoms produced by arthropods act as chemical weapons to paralyze prey or deter competitors. The utilization of venom is an essential feature in the biology and ecology of venomous arthropods. Solenopsis fire ants (Hymenoptera: Formicidae) are medically important venomous ants. They have acquired different patterns of venom use to maximize their competitive advantages rendered by the venom when facing different challenges. The major components of fire ant venom are piperidine alkaloids, which have strong insecticidal and antibiotic activities. The alkaloids protect fire ants from pathogens over the course of their lives and can be used to defend them from predators and competitors. They are also utilized by some of the fire ants' natural enemies, such as phorid flies to locate host ants. Collectively, these ants' diverse alkaloid compositions and functions have ecological significance for their survival, successful invasion, and rapid range expansion. The venom alkaloids with powerful biological activities may have played an important role in shaping the assembly of communities in both native and introduced ranges.


Assuntos
Alcaloides , Venenos de Formiga , Formigas , Venenos de Artrópodes , Dípteros , Animais , Venenos de Formiga/farmacologia , Venenos de Formiga/química , Formigas/química , Alcaloides/farmacologia , Alcaloides/química
11.
Mar Genomics ; 68: 101018, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36894216

RESUMO

Bacillus subtilis TY-1 was isolated from 2000 m-deep sea sediments of the Western Pacific Ocean, which was found to exhibit strong antagonistic activity against tobacco bacterial wilt caused by Ralstonia solanacearum. Here, we present the annotated complete genomic sequence of the strain Bacillus subtilis TY-1. The genome consists of a 4,030,869-bp circular chromosome with a G + C content of 43.88%, 86 tRNAs, and 30 rRNAs. Genomic analysis identified a large number of gene clusters involved in the biosynthesis of antibacterial metabolites, including lipopeptides(surfactin, bacillibactin, and fengycin) and polyketides(bacillaene). Meanwhile, numerous genes encoding carbohydrate-active enzymes and secreted proteins were found in TY-1. These findings suggest that Bacillus subtilis TY-1 appears to be a potential biocontrol agent against tobacco bacterial wilt in agricultural fields.


Assuntos
Bacillus subtilis , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , /metabolismo , Genoma Bacteriano , Antibacterianos/metabolismo , Genômica
12.
Artif Intell Med ; 134: 102433, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36462897

RESUMO

Pathological diagnosis is considered as the benchmark for the detection of breast cancer. With the increasing number of patients, computer-aided histopathological image classification can assist pathologists in improving breast cancer diagnosis accuracy and working efficiency. However, a single model is insufficient for effective diagnosis, and this also does not accord with the principle of centralized decision-making. Starting from the real pathological diagnosis scenario, we propose a novel model fusion framework based on online mutual knowledge transfer (MF-OMKT) for breast cancer histopathological image classification. The OMKT part based on deep mutual learning (DML) imitates the mutual communication and learning between multiple experienced pathologists, which can break the isolation of single models and provides sufficient complementarity among heterogeneous networks for MF. The MF part based on adaptive feature fusion uses the complementarity to train a powerful fusion classifier. MF imitates the centralized decision-making process of these pathologists. We used the MF-OMKT model to classify breast cancer histopathological images (BreakHis dataset) into benign and malignant as well as eight subtypes. The accuracy of our model reaches the range of [99.27 %, 99.84 %] for binary classification. And that for multi-class classification reaches the range of [96.14 %, 97.53 %]. Additionally, MF-OMKT is applied to the classification of skin cancer images (ISIC 2018 dataset) and achieves an accuracy of 94.90 %. MF-OMKT is an effective and versatile framework for medical image classification.


Assuntos
Neoplasias da Mama , Neoplasias Cutâneas , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Mama , Aprendizagem , Comunicação
13.
Bioanalysis ; 14(11): 807-816, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35938284

RESUMO

Selection of the appropriate matrix for standard curve is critical for an accurate and sensitive biomarker method. Slope of a standard curve is the key factor for parallelism assessment between tested matrix and authentic matrix for LC-MS/MS assays. Here the authors have established slope criteria using a generic equation and endogenous level criteria for achieving assay sensitivity. The slope difference criterion is from -13.0 to +17.6% for LC-MS assays with ± 15% bias criteria. When the ratio of endogenous concentration in the tested matrix to the lower limit of quantitation is <4.0, the lower limit of quantitation is achievable. If these criteria are met, the tested matrix can be used for assays. The utility of the two criteria has been illustrated with case studies.


Assuntos
Espectrometria de Massas em Tandem , Biomarcadores , Cromatografia Líquida/métodos , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos
14.
Mar Drugs ; 20(3)2022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35323512

RESUMO

Four new dimeric sorbicillinoids (1-3 and 5) and a new monomeric sorbicillinoid (4) as well as six known analogs (6-11) were purified from the fungal strain Hypocrea jecorina H8, which was obtained from mangrove sediment, and showed potent inhibitory activity against the tea pathogenic fungus Pestalotiopsis theae (P. theae). The planar structures of 1-5 were assigned by analyses of their UV, IR, HR-ESI-MS, and NMR spectroscopic data. All the compounds were evaluated for growth inhibition of tea pathogenic fungus P. theae. Compounds 5, 6, 8, 9, and 10 exhibited more potent inhibitory activities compared with the positive control hexaconazole with an ED50 of 24.25 ± 1.57 µg/mL. The ED50 values of compounds 5, 6, 8, 9, and 10 were 9.13 ± 1.25, 2.04 ± 1.24, 18.22 ± 1.29, 1.83 ± 1.37, and 4.68 ± 1.44 µg/mL, respectively. Additionally, the effects of these compounds on zebrafish embryo development were also evaluated. Except for compounds 5 and 8, which imparted toxic effects on zebrafish even at 0.625 µM, the other isolated compounds did not exhibit significant toxicity to zebrafish eggs, embryos, or larvae. Taken together, sorbicillinoid derivatives (6, 9, and 10) from H. jecorina H8 displayed low toxicity and high anti-tea pathogenic fungus potential.


Assuntos
Ascomicetos/efeitos dos fármacos , Agentes de Controle Biológico , Hypocreales/química , Policetídeos , Animais , Ascomicetos/crescimento & desenvolvimento , Agentes de Controle Biológico/química , Agentes de Controle Biológico/isolamento & purificação , Agentes de Controle Biológico/farmacologia , Agentes de Controle Biológico/toxicidade , Camellia sinensis/microbiologia , Embrião não Mamífero , Estrutura Molecular , Policetídeos/química , Policetídeos/isolamento & purificação , Policetídeos/farmacologia , Policetídeos/toxicidade , Peixe-Zebra
15.
Curr Microbiol ; 79(4): 95, 2022 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-35150317

RESUMO

Microbes living in extreme environments often adopt strategies for survival, however, only a few studies have examined the adaptive mechanism of deep-sea bacteria in in-situ environments. In this study, transcriptomic data of the deep-sea piezotolerant and psychrotolerant actinomycete Microbacterium sediminis YLB-01 under the conditions of NPNT (normal temperature and pressure: 28 °C, 0.1 MPa), HPNT (normal temperature and high pressure: 28 °C, 30 MPa), NPLT (low temperature and atmospheric pressure: 4 °C, 0.1 MPa) and HPLT (low temperature and high pressure: 4 °C, 30 MPa) were examined and compared. Transcriptome results showed that M. sediminis YLB-01 responds to deep-sea low temperature under high-pressure environments by upregulating the ABC transport system, DNA damage repair response, pentose phosphate pathway, amino acid metabolism and fatty acid metabolism, while down-regulating division, oxidative phosphorylation, the TCA cycle, pyruvate metabolism, ion transport and peptidoglycan biosynthesis. Seven key genes specifically expressed under HPLT conditions were screened, and these genes are present in many strains that are tolerant to low temperatures and high pressures. This study provides transcription level insights into the tolerance mechanisms of M. sediminis YLB-01 in a simulated deep-sea in situ environment.


Assuntos
Actinomycetales , Transcriptoma , Actinomycetales/genética , Pressão Hidrostática , Microbacterium , Temperatura
16.
Molecules ; 27(3)2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-35164372

RESUMO

2,6-dialkylpiperideines found in the venom of Solenopsis (Hymenoptera, Formicidae) fire ants are a range of compounds possessing various biological activities. A series of racemic 2-methyl-6-alkyl-Δ1,6-piperideines were synthesized for chemical confirmation of the natural products found in fire ant venom, and the evaluation of their biological activity. Synthetic Δ1,6-piperideines and the natural compounds in the cis-alkaloid fraction of Solenopsis invicta had identical mass spectra and retention times. Their insecticidal activities against the third-instar larvae of cotton bollworm (Helicoverpa armigera) were evaluated by using injection and topical application methods. All three compounds exhibited no lethal effect at concentrations of 0.05-0.4 mol/L by topical treatment, but moderate lethal effect at 0.4 mol/L through injection treatment. Compound 6a showed significantly higher activity than the natural insecticide nicotine. The differences in activity among compounds 6b, 6c and nicotine were not significant. The elongation of the carbon chain at the 6-position of the piperideine ring appears to decrease insecticidal activity.


Assuntos
Alcaloides/farmacologia , Venenos de Formiga/farmacologia , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Mariposas/efeitos dos fármacos , Piperidinas/química , Piperidinas/farmacologia , Animais , Inseticidas/síntese química , Larva/crescimento & desenvolvimento , Mariposas/crescimento & desenvolvimento
17.
Arch Microbiol ; 203(6): 3279-3285, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33860341

RESUMO

A halophilic, Gram-staining-negative, rod-shaped, flagellated and motile bacterium, strain QX-1 T, was isolated from deep-sea sediment at a depth of 3332 m in the southwestern Indian Ocean. Strain QX-1 T growth was observed at 4-50 °C (optimum 37 °C), pH 5.0-11.0 (optimum pH 7.0), 3-25% NaCl (w/v; optimum 7%), and it did not grow without NaCl. A phylogenetic analysis based on the 16S rRNA gene placed strain QX-1 T in the genus Halomonas and most closely related to Halomonas sulfidaeris (97.9%), Halomonas zhaodongensis (97.8%), Halomonas songnenensis (97.6%), Halomonas hydrothermalis (97.4%), Halomonas subterranea (97.3%), Halomonas salicampi (97.1%), and Halomonas arcis (97.0%). DNA-DNA hybridization (< 26.5%) and average nucleotide identity values (< 83.5%) between strain QX-1 T and the related type strains meet the accepted criteria for a new species. The principal fatty acids (> 10%) of strain QX-1 T are C16:0 (25.5%), C17:0 cyclo (14.0%), C19:0 cyclo ω8c (18.7%), and summed feature 8 (C18:1 ω7c and/or C18:1 ω6c, 18.1%). The polar lipids of strain QX-1 T are mainly diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, unidentified phospholipid, unidentified aminophospholipid, and five unidentified lipids. The main respiratory quinone is Q-9. The G + C content of its chromosomal DNA is 54.4 mol%. Its fatty acid profile, respiratory quinones, and G + C content also support the placement of QX-1 T in the genus Halomonas. These phylogenetic, phenotypic, and chemotaxonomic analyses indicate that QX-1 T is a novel species, for which the name Halomonas maris is proposed. The type strain is QX-1 T (= MCCC 1A17875T = KCTC 82198 T = NBRC 114670 T).


Assuntos
Sedimentos Geológicos/microbiologia , Halomonas/isolamento & purificação , Composição de Bases , DNA Bacteriano/química , Ácidos Graxos/análise , Halomonas/química , Halomonas/classificação , Halomonas/genética , Oceano Índico , Lipídeos/análise , Filogenia , Tolerância ao Sal
18.
Curr Microbiol ; 78(4): 1662-1669, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33651187

RESUMO

A Gram-staining-negative, aerobic, flagellated, motile, rod-shaped, halophilic bacterium QX-2T was isolated from the deep-sea sediment of the Southwest Indian Ocean at a depth of 2699 m. Growth of the QX-2T bacteria was observed at 4-50 °C (optimum 30 °C), pH 5.0-12.0 (optimum pH 6.0) and 0%-30% NaCl (w/v) [optimum 4% (w/v)]. 16S rRNA gene sequencing revealed that strain QX-2T has the closest relationship with Halomonas titanicae DSM 22872T (98.2%). Phylogeny analysis classified the strain QX-2T into the genus Halomonas. The average nucleotide identity and DNA-DNA hybridization values between strain QX-2T and related type strains were lower than the currently accepted new species definition standards. Principal fatty acids (> 10%) determined were C16:0 (12.41%), C12:0-3OH (25.15%), summed feature 3 (C16:1 ω7c and/or C16:1 ω6c, 11.55%) and summed feature 8 (C18:1 ω7c and/or C18:1 ω6c, 16.06%). Identified polar lipids in strain QX-2T were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, unidentified phospholipid, unidentified aminophospholipid and five unidentified lipids (L1-L5). The main respiratory quinone was Q-9. The content of DNA G+C was determined to be 54.34 mol%. The results of phylogenetic analysis, phenotypic analysis and chemotaxonomic studies showed that strain QX-2T represents a novel species within the genus Halomonas, for which the name Halomonas sedimenti sp. nov. is proposed, with the type strain QX-2T (MCCC 1A17876T = KCTC 82199T).


Assuntos
Halomonas , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/análise , Halomonas/genética , Oceano Índico , Fosfolipídeos/análise , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
19.
Nat Prod Res ; 35(21): 3772-3779, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32159393

RESUMO

Three new cyclopentenoneacrylic acid derivatives, trichodermacid A (1), trichodermester A (2), and trichodermester B (3), together with thirteen known compounds, were isolated from an ethyl acetate extract of Trichoderma atroviride H548, a fungus derived from mangrove sediment. The structures of the new compounds were elucidated by spectroscopic methods including HR ESI-MS, 1H NMR, 13C NMR, and 2D-NMR techniques. The antifungal activity of the isolated compounds was evaluated against tea pathogenic fungus Pestalotiopsis theae. Trichodermester A (2) showed potent anti P. theae activity with MIC of 125 µg/disc, while the other compounds were inactive.


Assuntos
Trichoderma , Xylariales , Antifúngicos/farmacologia , Hypocreales , Estrutura Molecular
20.
Antonie Van Leeuwenhoek ; 113(3): 389-396, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31628627

RESUMO

A Gram-positive, rod-shaped, endospore-forming bacterium with multiple flagella, designated XXST-01T, was isolated from deep-sea sediment of Yap Trench with a depth of 6300 m. Activity of oxidase and catalase were found to be positive. Growth was observed at 10-45 °C (optimum 37 °C), pH 6-9 (optimum 7.0), 0-6% NaCl (optimum 0-0.5%, w/v) and 0.1-50 MPa (optimum 0.1 MPa). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain XXST-01T belonged to the genus Bacillus. Strain XXST-01T was closely related to Bacillus kyonggiensis NB22T (98.4%), Bacillus siralis 171544T (97.53%), Bacillus massiliosenegalensis JC6T (97.30%), Bacillus oceanisediminis H2T (97.27%), Bacillus mesophilum IITR-54T (97.12%) and Bacillus depressus BZ1T (97.09%). The ANI and the DNA-DNA hybridization estimate values between strain XXST-01T and closely related type strains were 70.91-90.15% and 19.80-40.50%, respectively. The principal fatty acids were iso-C15:0, anteiso-C15:0, iso-C16:0, and iso-C14:0. The G+C content of the chromosomal DNA was 38.2 mol%. The respiratory quinone was determined to be MK-7. The polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, an unidentified phospholipid and four unidentified aminophospholipids. The combined genotypic and phenotypic data show that strain XXST-01T represents a novel species within the genus Bacillus, for which the name Bacillus yapensis sp. nov. is proposed, with the type strain XXST-01T (=MCCC 1A14143T = JCM 33181T).


Assuntos
Bacillus/classificação , Sedimentos Geológicos/microbiologia , Água do Mar/microbiologia , Organismos Aquáticos , Bacillus/isolamento & purificação , Bacillus/fisiologia , Técnicas de Tipagem Bacteriana , Oceano Pacífico , Fenótipo , Filogenia , RNA Ribossômico 16S/genética
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