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1.
iScience ; 27(3): 109290, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38469562

RESUMO

Our research addresses the critical intersection of communication and power systems in the era of advanced information technologies. We highlight the strategic importance of communication base station placement, as its optimization is vital for minimizing operational disruptions in energy systems. Our study introduces a communications and power coordination planning (CPCP) model that encompasses both distributed energy resources and base stations to improve communication quality of service. This model facilitates optimal resource distribution, ensuring communication reliability over 96% and downlink transmission rates above 450 Mbps, enhancing network resilience and cost-effectiveness. Through case studies, we demonstrate CPCP's potential to significantly reduce planning costs, particularly with increased renewable energy integration, supporting the transition to low-carbon energy systems. Our findings contribute to a comprehensive understanding of the symbiotic relationship between communication and power networks, emphasizing the need for coordinated planning in building future-proof energy infrastructures.

2.
Eur J Pharmacol ; 970: 176491, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38503399

RESUMO

Alzheimer's disease (AD) is a progressive neurodegenerative disease with the hallmark of aggregation of beta-amyloid (Aß) into extracellular fibrillar deposition. Accumulating evidence suggests that soluble toxic Aß oligomers exert diverse roles in neuronal cell death, oxidative stress, neuroinflammation, and the eventual pathogenesis of AD. Aß is derived from the sequential cleavage of amyloid-ß precursor protein (APP) by ß-secretase (BACE1) and γ-secretase. The current effect of single targeting is not ideal for the treatment of AD. Therefore, developing multipotent agents with multiple properties, including anti-Aß generation and anti-Aß aggregation, is attracting more attention for AD treatment. Previous studies indicated that Quercetin was able to attenuate the effects of several pathogenetic factors in AD. Here, we showed that naturally synthesized Quercetin-3-O-glc-1-3-rham-1-6-glucoside (YCC31) could inhibit Aß production by reducing ß-secretase activity. Further investigations indicated that YCC31 could suppress toxic Aß oligomer formation by directly binding to Aß. Moreover, YCC31 could attenuate Aß-mediated neuronal death, ROS and NO production, and pro-inflammatory cytokines release. Taken together, YCC31 targeting multiple pathogenetic factors deserves further investigation for drug development of AD.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Humanos , Secretases da Proteína Precursora do Amiloide/metabolismo , Quercetina/farmacologia , Quercetina/uso terapêutico , Citocinas , Ácido Aspártico Endopeptidases/metabolismo , Ácido Aspártico Endopeptidases/uso terapêutico , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Glucosídeos/uso terapêutico
3.
World J Pediatr ; 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38388968

RESUMO

BACKGROUND: Alanine aminotransferase (ALT) is widely used to screen patients with hepatic diseases. However, the current reference ranges (< 50 U/L) were developed by laboratories and have not been validated in populations with a large number of healthy individuals. METHODS: This study collected venous blood and anthropometric data from a total of 13,287 healthy children aged 3 months to 18 years who underwent routine physical examinations in the Department of Pediatric Healthcare. We applied the least mean square algorithm to establish age- and sex-related reference percentiles of serum levels of transaminases. For validation, we recruited 4276 children and adolescents with obesity/overweight who underwent evaluation and metabolic tests in the hospital. Using receiver operating characteristic curves, we determined age- and sex-specific upper limit percentiles of liver enzymes for fatty liver diseases. RESULTS: This study revealed a significant correlation between serum transaminase levels and age and sex (P < 0.01). These transaminase levels exhibited age- and sex-specific patterns. Among individuals in the non-alcoholic fatty liver disease (NAFLD) cohort, elevated ALT levels displayed a positive association with clinical markers of disease severity, including homeostatic model assessment of insulin resistance, waist-hip ratio, and serum uric acid levels (P < 0.01). According to the receiver operating characteristic curves, ALT levels at the 92.58th percentile for boys and the 92.07th percentile for girls yielded the highest accuracy and specificity. CONCLUSIONS: This study provides age- and sex-specific reference ranges for ALT, aspartate aminotransferase, and γ-glutamyltransferase in Chinese children and adolescents, making it the largest population study to date. Furthermore, the study establishes a precise upper limit for ALT levels, facilitating their use in NAFLD screening. Video Abstract.

4.
Int J Mol Sci ; 25(4)2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38396642

RESUMO

Restricted production of fungal secondary metabolites hinders the ability to conduct comprehensive research and development of novel biopesticides. Okaramine B from Penicillium demonstrates remarkable insecticidal efficacy; however, its biosynthetic yield is low, and its regulatory mechanism remains unknown. The present study found that the yield difference was influenced by fermentation modes in okaramine-producing strains and performed genomic and comparative transcriptome analysis of P. daleae strain NBP-49626, which exhibits significant features. The NBP-49626 genome is 37.4 Mb, and it encodes 10,131 protein-encoding genes. Up to 5097 differentially expressed genes (DEGs) were identified during the submerged and semi-solid fermentation processes. The oka gene cluster, lacking regulatory and transport genes, displayed distinct transcriptional patterns in response to the fermentation modes and yield of Okaramine B. Although transcription trends of most known global regulatory genes are inconsistent with those of oka, this study identified five potential regulatory genes, including two novel Zn(II)2Cys6 transcription factors, Reg2 and Reg19. A significant correlation was also observed between tryptophan metabolism and Okaramine B yields. In addition, several transporter genes were identified as DEGs. These results were confirmed using real-time quantitative PCR. This study provides comprehensive information regarding the regulatory mechanism of Okaramine B biosynthesis in Penicillium and is critical to the further yield improvement for the development of insecticides.


Assuntos
Azetidinas , Azocinas , Alcaloides Indólicos , Penicillium , Penicillium/metabolismo , Perfilação da Expressão Gênica , Genômica/métodos
5.
Diabetol Metab Syndr ; 16(1): 28, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38287388

RESUMO

BACKGROUND: Throughout the COVID-19 pandemic, there has been a notable increase in the incidence of new-onset diabetes and diabetic ketoacidosis (DKA). Simultaneously, children diagnosed with type 1 diabetes (T1D) have encountered difficulties in maintaining optimal blood glucose levels. The mechanisms underpinning these correlations still remain a puzzle. We reviewed the studies that examined changes in incidence during the pandemic. These studies utilized various metrics for comparison, which encompassed the timing of data collection, diagnostic criteria, as well as the numbers and incidence rates of diabetes and DKA. We found the incidence of diabetes and DKA was higher during the pandemic. As to mechanisms, the invivo and invitro study revealed the factors such as direct viral damage, metabolic dysfunction, and immune responses all attribute to the process of T1D after suffering from COVID-19. Furthermore, we provide some useful strategies to prevent and treat children suffering from diabetes and COVID-19. CONCLUSIONS: Strong correlations have been observed between new-onset diabetes and COVID-19. Insights gleaned from clinical descriptions and basic research can offer valuable experience and recommendations for the treatment and prevention of diabetes during future pandemics.

6.
Quant Imaging Med Surg ; 14(1): 144-159, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38223047

RESUMO

Background: In 2020, our center established a Tanner-Whitehouse 3 (TW3) artificial intelligence (AI) system using a convolutional neural network (CNN), which was built upon 9059 radiographs. However, the system, upon which our study is based, lacked a gold standard for comparison and had not undergone thorough evaluation in different working environments. Methods: To further verify the applicability of the AI system in clinical bone age assessment (BAA) and to enhance the accuracy and homogeneity of BAA, a prospective multi-center validation was conducted. This study utilized 744 left-hand radiographs of patients, ranging from 1 to 20 years of age, with 378 boys and 366 girls. These radiographs were obtained from nine different children's hospitals between August and December 2020. The BAAs were performed using the TW3 AI system and were also reviewed by experienced reviewers. Bone age accuracy within 1 year, root mean square error (RMSE), and mean absolute error (MAE) were statistically calculated to evaluate the accuracy. Kappa test and Bland-Altman (B-A) plot were conducted to measure the diagnostic consistency. Results: The system exhibited a high level of performance, producing results that closely aligned with those of the reviewers. It achieved a RMSE of 0.52 years and an accuracy of 94.55% for the radius, ulna, and short bones series. When assessing the carpal series of bones, the system achieved a RMSE of 0.85 years and an accuracy of 80.38%. Overall, the system displayed satisfactory accuracy and RMSE, particularly in patients over 7 years old. The system excelled in evaluating the carpal bone age of patients aged 1-6. Both the Kappa test and B-A plot demonstrated substantial consistency between the system and the reviewers, although the model encountered challenges in consistently distinguishing specific bones, such as the capitate. Furthermore, the system's performance proved acceptable across different genders and age groups, as well as radiography instruments. Conclusions: In this multi-center validation, the system showcased its potential to enhance the efficiency and consistency of healthy delivery, ultimately resulting in improved patient outcomes and reduced healthcare costs.

7.
Hepatol Int ; 18(1): 179-187, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37861942

RESUMO

OBJECTIVE: Previous studies have reported sex differences in non-alcoholic fatty liver disease (NAFLD) among adults; however, little is known about its occurrence in children and adolescents. This study aims to examine the prevalence of NAFLD among them and investigate the relationship between sex hormones and NAFLD. METHOD: This study included 2999 obese Chinese children aged 2-18 years. We examined the prevalence of NAFLD by sex, age, and Tanner stage. The regression model and principal component analysis were used to analyze the relationship between sex hormones and NAFLD. RESULTS: The prevalence of NAFLD increased with age in both sexes, and the gender difference appeared before puberty. The prevalence in boys tended to stabilize at the age of 11 years, whereas girls reached their peak temporarily. NAFLD prevalence was positively associated with estradiol in boys (p = 0.011), but the opposite trend was observed in girls (p = 0.031). Testosterone levels decreased with the increase of NAFLD prevalence in boys (p < 0.001). Luteinizing hormone and prolactin were inversely associated with NAFLD prevalence in boys and girls, respectively. Results from the principal component analysis showed that sex hormone levels and fat distribution were important risk factors for the prevalence of NAFLD in obese children (p < 0.001). CONCLUSION: The significant difference in NAFLD prevalence between genders in obese children begins in early childhood. This distinction emerges long before puberty onset and tends to stabilize during late adolescence. Sex hormones are associated with NAFLD prevalence and are influenced by the Tanner stages and fat distribution.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Obesidade Pediátrica , Adulto , Humanos , Feminino , Masculino , Criança , Pré-Escolar , Adolescente , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Estudos Transversais , Obesidade Pediátrica/epidemiologia , Fatores Sexuais , Hormônios Esteroides Gonadais , Prevalência , Índice de Massa Corporal
8.
Eur J Clin Nutr ; 77(12): 1167-1172, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37587242

RESUMO

BACKGROUND/OBJECTIVE: Several body components are known to be associated with non-alcoholic fatty liver disease (NAFLD) in children. However, the relative contributions of soft tissue mass components as risk or protective factors of NAFLD are largely unknown because measurements of these components are often highly correlated. Therefore, we aimed to estimate levels of association between soft tissue mass components and NAFLD. SUBJECTS/METHODS: We collected the medical records of 555 Chinese children (aged 3-18 years). Five mutually exclusive and exhaustive components of soft tissue mass were measured using dual energy X-ray absorptiometry. NAFLD was diagnosed with abdominal B-ultrasound scan. We fit Dirichlet regression and multivariate linear regression models wherein age and NAFLD were used as predictors of the proportional measurements of soft tissue mass components. RESULTS: The proportion of android fat was significantly higher in children with NAFLD than in those without NAFLD (ratio of proportions ranged from 1.18 to 1.30), whereas proportions of trunk lean and limb lean were significantly lower (ratio of proportions ranged from 0.87 to 0.92 for trunk lean and from 0.82 to 0.91 for limb lean). The proportion of gynoid fat was slightly higher in boys with NAFLD than in those without NAFLD (ratio = 1.05), but this proportion was not significantly higher in girls. The association between the proportion of android fat and NAFLD appeared to be somewhat greater than the associations between proportions of trunk lean or limb lean components and NAFLD. CONCLUSION: Our findings suggest that lowering fat mass and increasing lean mass can both be used to combat NAFLD in children and that more studies are needed to determine the association between gynoid fat and NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Masculino , Feminino , Humanos , Criança , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Fatores de Proteção , Absorciometria de Fóton , Índice de Massa Corporal , Fatores de Risco
9.
Molecules ; 28(2)2023 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-36677698

RESUMO

Two new napyradiomycins derivatives, napyradiomycin A4 (1) and A80915 H (2), along with five known ones, were isolated from the ethyl acetate extract of fermentation culture of Streptomyces kebangsaanensis WS-68302. Their structures were elucidated by extensive spectroscopic analysis, including HR-MS, 1D and 2D NMR, CD spectrum, as well as comparison with literature data. Compound 1 exhibited significant antiviral activity against PRV (Pseudorabies virus) with an IC50 value of 2.056 µM and therapeutic ratio at 14.98, suggesting that it might have potential for development of an antiviral agent. Moreover, compound 1 displayed the strongest inhibition against PRV protein among the tested napyradiomycins in the indirect immunofuorescence assay. Compounds 3 and 4 showed higher activities against swine pathogenic Streptococcus suis than the positive control penicillin G sodium salt, with MIC values of 3.125 and 6.25 µg/mL, respectively. Compounds 1 and 3-6 exhibited moderate antibacterial activity against the swine pathogenic Erysipelothrix rhusiopathiae, with MIC values ranging from 25 to 50 µg/mL.


Assuntos
Antibacterianos , Streptomyces , Animais , Suínos , Antibacterianos/química , Streptomyces/química , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana
10.
Molecules ; 28(2)2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36677936

RESUMO

Pseudorabies virus (PRV) is a pathogen that causes Aujeszky's disease (AD) in animals, leading to huge economic losses to swine farms. In order to discover anti-PRV compounds, we studied the extracts of the strain Streptomyces jiujiangensis NBERC-24992, which showed significant anti-PRV activity. Eight benzoheterocyclic secondary metabolites, including three new compounds (1-3, virantmycins D-G) and five known compounds (4-8, virantmycin, A-503451 D, A-503451 D acetylate, A-503451 A, and A-503451 B), were isolated from the broth of NBERC-24992. The structures of the new compounds were identified by using extensive spectroscopic data, including mass spectrometry (MS), nuclear magnetic resonance (NMR), and electronic circular dichroism (ECD). Compound 1 was found to be a novel heterocyclic compound with a tricyclic skeleton from natural product. All compounds were tested for antiviral activity, and 4 (virantmycin) showed an excellent effect against PRV and was better than ribavirin and acyclovir. Our study revealed that chlorine atom and tetrahydroquinoline skeleton were important active moiety for antiviral activity. Virantmycin could be a suitable leading compound for an antiviral drug against PRV.


Assuntos
Herpesvirus Suídeo 1 , Pseudorraiva , Streptomyces , Suínos , Animais , Antivirais/uso terapêutico , Pseudorraiva/tratamento farmacológico , Streptomyces/metabolismo
11.
Plants (Basel) ; 12(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36616333

RESUMO

Fungi have been used in the production of a wide range of biologically active metabolites, including potent herbicides. In the search for pesticides of natural origin, Aspergillus sparsus NBERC_28952, a fungal strain with herbicidal activity, was obtained. Chemical study of secondary metabolites from NBERC_28952 resulted in the isolation of three new asperugin analogues, named Aspersparin A-C (2-4), and a new azaphilone derivative, named Aspersparin D (5), together with two known compounds, Asperugin B (1) and sydonic acid (6). The structures of these compounds were elucidated based on extensive spectroscopic data and single-crystal X-ray diffraction analysis. All of the isolated compounds were evaluated for their herbicidal activities on seedlings of Echinochloa crusgalli and Amaranthus retroflexus through Petri dish bioassays. Among them, compounds 5 and 6 exhibited moderate inhibitory activities against the growth of the roots and shoots of E. crusgalli seedlings in a dose-dependent manner, while 6 showed obvious inhibitory effect on seedlings of A. retroflexus, with an inhibitory rate of 78.34% at a concentration of 200 µg/mL. These herbicidal metabolites represent a new source of compounds to control weeds.

12.
Plant Dis ; 107(6): 1920-1924, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36471473

RESUMO

Trichothecium roseum is widely distributed throughout the world and forms pink powdery molds on various fruits and vegetables, lowering their quality and leading to great economic losses. Due to the limited availability of high-quality genomic and annotation resources, little is known about the pathogenesis of T. roseum at the molecular level. In this study, we reported a high-quality genome assembly of strain YXFP-22015 using Oxford Nanopore Technologies (ONT) for long read sequencing and MGISEQ-2000 for short read sequencing. The genome was also well-annotated based on the combination of RNA-seq by MGISEQ-2000 and in silico prediction. Further analysis on this will contribute to a better understanding of T. roseum infection mechanisms.


Assuntos
Hypocreales , Genômica , Frutas , China
13.
Plants (Basel) ; 11(23)2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36501441

RESUMO

Weeds cause significant yield losses in crop production and influence the health of animals and humans, with some exotic weeds even leading to ecological crises. Weed control mainly relies on the application of chemical herbicides, but their adverse influences on the environment and food safety are a significant concern. Much effort has been put into using microbes as bioherbicides for weed control. As plant-associated bacteria (PAB), they are widely present in the rhizophere, inside crops or weeds, or as pathogens of weeds. Many species of PAB inhibit the seed germination and growth of weeds through the production of phytotoxic metabolites, auxins, hydrogen cyanide, etc. The performance of PAB herbicides is influenced by environmental factors, formulation type, surfactants, additives, application methods, and cropping measures, etc. These factors might explain the inconsistencies between field performance and in vitro screening results, but this remains to be clarified. Successful bioherbicides must be specific to the target weeds or the coinciding weeds. Detailed studies, regarding factors such as the formulation, application techniques, and combination with cultivation measures, should be carried out to maximize the performance of PAB-based bioherbicides.

14.
Front Endocrinol (Lausanne) ; 13: 986841, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36120457

RESUMO

Objective: This study aims to outline the clinical characteristics of pediatric NAFLD, as well as establish and validate a prediction model for the disease. Materials and methods: The retrospective study enrolled 3216 children with obesity from January 2003 to May 2021. They were divided into obese without NAFLD, nonalcoholic fatty liver (NAFL), and nonalcoholic steatohepatitis (NASH) groups. Clinical data were retrieved, and gender and chronologic characteristics were compared between groups. Data from the training set (3036) were assessed using univariate analyses and stepwise multivariate logistic regression, by which a nomogram was developed to estimate the probability of NAFLD. Another 180 cases received additional liver hydrogen proton magnetic resonance spectroscopy (1H-MRS) as a validation set. Results: The prevalence of NAFLD was higher in males than in females and has increased over the last 19 years. In total, 1915 cases were NAFLD, and the peak onset age was 10-12 years old. Hyperuricemia ranked first in childhood NAFLD comorbidities, followed by dyslipidemia, hypertension, metabolic syndrome (MetS), and dysglycemia. The AUROC of the eight-parameter nomogram, including waist-to-height ratio (WHtR), hip circumference (HC), triglyceride glucose-waist circumference (TyG-WC), alanine aminotransferase (ALT), high-density lipoprotein cholesterol (HDL-C), apolipoprotein A1(ApoA1), insulin sensitivity index [ISI (composite)], and gender, for predicting NAFLD was 0.913 (sensitivity 80.70%, specificity 90.10%). Calibration curves demonstrated a great calibration ability of the model. Conclusion and relevance: NAFLD is the most common complication in children with obesity. The nomogram based on anthropometric and laboratory indicators performed well in predicting NAFLD. This can be used as a quick screening tool to assess pediatric NAFLD in children with obesity.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Alanina Transaminase , Apolipoproteína A-I , Criança , Colesterol , Feminino , Glucose , Humanos , Lipoproteínas HDL , Masculino , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Obesidade/complicações , Estudos Retrospectivos , Triglicerídeos
15.
Front Chem ; 10: 953523, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35903190

RESUMO

Diarylamines are a class of important skeleton widely existing in drugs or natural products. To discover novel diarylamine analogues as potential drugs, two series of diamide and carboxamide derivatives containing diarylamine scaffold were designed, synthesized and evaluated for their potential cytotoxic activities. The bioassay results indicated that some of the obtained compounds (C5, C6, C7, C11) exhibited good cytotoxic effect on cancer cell lines (SGC-7901, A875, HepG2), especially, compound C11 present significantly selective proliferation inhibition activity on cancer and normal cell lines (MARC145). In addition, the possible apoptosis induction for highly potential molecules was investigated, which present compound C11 could be used as novel lead compound for discovery of promising anticancer agents.

16.
J Antibiot (Tokyo) ; 75(7): 375-379, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35595884

RESUMO

Two new 1,4,6-trihydroxy-8-alkylated-9,10-anthraquinones (1-2) were isolated from the culture broth of the soil actinomycete Streptomyces sp. WS-13394. Their structures were elucidated on the basis of extensive spectroscopic analysis, including mass spectrometry (MS), nuclear magnetic resonance (NMR), and electronic circular dichroism (ECD). Compounds 1 and 2, together with eight analogs (3-10), were evaluated for their antibacterial activities against five pathogens. The tested derivatives of alkylated anthraquinone exhibited selective activities to Gram-positive bacteria, while compounds 1 and 5 showed obvious activities against two zoonotic pathogens, Erysipelothrix rhusiopathiae and Streptococcus suis, with MIC values ranging from 3.13 to 12.5 µg ml-1.


Assuntos
Streptomyces , Antraquinonas , Antibacterianos/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Solo , Streptomyces/química
17.
J Antibiot (Tokyo) ; 74(7): 474-476, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34021266

RESUMO

Two new dipimprinine alkaloids dipimprinine E (1) and dipimprinine F (2) were isolated from Streptomyces sp. 44414B. The structure was elucidated by extensive spectroscopic analysis, including ESI-MS, HR-MS, and 1D and 2D NMR experiments. Dipimprinines F (2) showed cytotoxic activities against three tumor cell lines, including A-875, Hep G2, and H-460, with IC50 values of 26.4, 0.5, and 9.0 µg ml-1, respectively.


Assuntos
Alcaloides/química , Alcaloides/farmacologia , Antineoplásicos/farmacologia , Streptomyces/química , Antineoplásicos/química , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Oxazóis/química , Microbiologia do Solo , Espectrometria de Massas por Ionização por Electrospray , Streptomyces/isolamento & purificação
18.
Molecules ; 26(7)2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33915741

RESUMO

As an important zoonotic pathogen, Streptococcus suis (S. suis) can cause a variety of diseases both in human and animals, especially Streptococcal toxic shock-like syndrome (STSLS), which commonly appears in severe S. suis infection. STSLS is often accompanied by excessive production of inflammatory cytokines, which is the main cause of host death. Therefore, it is urgent to find a new strategy to relieve the damage caused by STSLS. In this study, we found, for the first time, that apigenin, as a flavonoid compound, could combine with ampicillin to treat severe S. suis infection. Studies found that apigenin did not affect the growth of S. suis and the secretion of suilysin (SLY), but it could significantly inhibit the hemolytic activity of SLY by directly binding to SLY and destroying its secondary structure. In cell assays, apigenin was found to have no significant toxic effects on effective concentrations, and have a good protective effect on S. suis-infected cells. More importantly, compared with the survival rate of S. suis-infected mice treated with only ampicillin, the survival rate of apigenin combined with an ampicillin-treated group significantly increased to 80%. In conclusion, all results indicate that apigenin in combination with conventional antibiotics can be a potential strategy for treating severe S. suis infection.


Assuntos
Ampicilina/farmacologia , Antibacterianos/farmacologia , Apigenina/farmacologia , Infecções Estreptocócicas/tratamento farmacológico , Infecções Estreptocócicas/microbiologia , Streptococcus suis/efeitos dos fármacos , Ampicilina/química , Ampicilina/uso terapêutico , Animais , Antibacterianos/química , Apigenina/química , Apigenina/uso terapêutico , Sítios de Ligação , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Eritrócitos/efeitos dos fármacos , Proteínas Hemolisinas/antagonistas & inibidores , Proteínas Hemolisinas/química , Interações Hospedeiro-Patógeno , Humanos , Mediadores da Inflamação/metabolismo , Camundongos , Testes de Sensibilidade Microbiana , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Ligação Proteica , Infecções Estreptocócicas/diagnóstico , Infecções Estreptocócicas/metabolismo , Relação Estrutura-Atividade , Resultado do Tratamento
19.
Antibiotics (Basel) ; 10(1)2020 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-33396878

RESUMO

Streptococcal toxic shock-like syndrome (STSLS) likely occurs when an individual is infected with the Streptococcus suis (S. suis) epidemic strain and is characterized by a cytokine storm, multiple organ dysfunction syndrome (MODS) and a high incidence of mortality despite adequate treatment. A number of antibiotics exhibit excellent bactericidal effects in vivo, such as fluoroquinolones, aminoglycosides (gentamicin) and ß-lactams (penicillin G, ceftiofur, or amoxicillin), but are less effective for treating STSLS. Therefore, there is an urgent need to identify new compounds that can reduce the damage caused by STSLS. In the present study, we identified auranofin, an orally bioavailable FDA-approved anti-rheumatic drug as a candidate repurposed drug to treat severe S. suis infections. Our results showed that auranofin can bind to the functional domain of bacterial thioredoxin reductase, decreasing the reducing redox-responsive capacity of target bacteria and allowing for the killing of S. suis cells. We also observed that auranofin has antibacterial activity against other gram-positive bacteria, such as multidrug resistant Streptococcus pneumoniae (MDRSP), Streptococcus agalactiae, and vancomycin-resistant strains of Staphylococcus aureus. Additionally, auranofin is capable of eradicating intracellular S.suis present inside infected macrophage cells. Mouse model experimental results showed that auranofin could effectively reduce the mortality of mice infected with S. suis. Compared to the ampicillin treatment group, the survival rate of mice in the auranofin treatment group in severely infected model mice was significantly improved. These results suggest that auranofin has the potential for use as an effective antibiotic against S. suis.

20.
J Agric Food Chem ; 68(1): 17-32, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31809036

RESUMO

Weeds had caused significant loss for crop production in the process of agriculture. Herbicides have played an important role in securing crop production. However, the high reliance on herbicides has led to environmental issues as well as the evolution of herbicide resistance. Thus, there is an urgent need for new herbicides with safer toxicological profiles and novel modes of action. Actinomycetes produce very diverse bioactive compounds, of which some show potent biopesticidal activity. The herbicidal secondary metabolites from actinomycetes can be classified into several groups, such as amino acids, peptides, nucleosides, macrolides, lactones, amide, amines, etc., some of which have been successfully developed as commercial herbicides. The structure diversity and evolved biological activity of secondary metabolites from actinomycetes can offer opportunities for the development of both directly used bioherbicides and synthetic herbicides with new target sites, and thus, this review focuses on the structure, herbicidal activity, and modes of action of secondary metabolites from actinomycetes.


Assuntos
Actinobacteria/química , Herbicidas/química , Herbicidas/farmacologia , Actinobacteria/metabolismo , Descoberta de Drogas , Herbicidas/metabolismo , Plantas Daninhas/efeitos dos fármacos , Plantas Daninhas/crescimento & desenvolvimento , Metabolismo Secundário , Controle de Plantas Daninhas
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