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1.
J Magn Reson Imaging ; 59(4): 1425-1435, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37403945

RESUMO

BACKGROUND: Dynamic contrast-enhanced (DCE) MRI commonly outperforms diffusion-weighted (DW) MRI in breast cancer discrimination. However, the side effects of contrast agents limit the use of DCE-MRI, particularly in patients with chronic kidney disease. PURPOSE: To develop a novel deep learning model to fully exploit the potential of overall b-value DW-MRI without the need for a contrast agent in predicting breast cancer molecular subtypes and to evaluate its performance in comparison with DCE-MRI. STUDY TYPE: Prospective. SUBJECTS: 486 female breast cancer patients (training/validation/test: 64%/16%/20%). FIELD STRENGTH/SEQUENCE: 3.0 T/DW-MRI (13 b-values) and DCE-MRI (one precontrast and five postcontrast phases). ASSESSMENT: The breast cancers were divided into four subtypes: luminal A, luminal B, HER2+, and triple negative. A channel-dimensional feature-reconstructed (CDFR) deep neural network (DNN) was proposed to predict these subtypes using pathological diagnosis as the reference standard. Additionally, a non-CDFR DNN (NCDFR-DNN) was built for comparative purposes. A mixture ensemble DNN (ME-DNN) integrating two CDFR-DNNs was constructed to identify subtypes on multiparametric MRI (MP-MRI) combing DW-MRI and DCE-MRI. STATISTICAL TESTS: Model performance was evaluated using accuracy, sensitivity, specificity, and area under the receiver operating characteristic curve (AUC). Model comparisons were performed using the one-way analysis of variance with least significant difference post hoc test and the DeLong test. P < 0.05 was considered significant. RESULTS: The CDFR-DNN (accuracies, 0.79 ~ 0.80; AUCs, 0.93 ~ 0.94) demonstrated significantly improved predictive performance than the NCDFR-DNN (accuracies, 0.76 ~ 0.78; AUCs, 0.92 ~ 0.93) on DW-MRI. Utilizing the CDFR-DNN, DW-MRI attained the predictive performance equal (P = 0.065 ~ 1.000) to DCE-MRI (accuracies, 0.79 ~ 0.80; AUCs, 0.93 ~ 0.95). The predictive performance of the ME-DNN on MP-MRI (accuracies, 0.85 ~ 0.87; AUCs, 0.96 ~ 0.97) was superior to those of both the CDFR-DNN and NCDFR-DNN on either DW-MRI or DCE-MRI. DATA CONCLUSION: The CDFR-DNN enabled overall b-value DW-MRI to achieve the predictive performance comparable to DCE-MRI. MP-MRI outperformed DW-MRI and DCE-MRI in subtype prediction. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY STAGE: 1.


Assuntos
Neoplasias da Mama , Aprendizado Profundo , Humanos , Feminino , Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias da Mama/patologia , Estudos Prospectivos , Imageamento por Ressonância Magnética/métodos , Meios de Contraste , Estudos Retrospectivos
2.
Curr Microbiol ; 81(7): 203, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38831185

RESUMO

Three Gram-stain-positive bacterial strains were isolated from traditional Chinese pickle and characterized using a polyphasic taxonomic approach. Results of 16S rRNA gene sequence analysis indicated that strain 74-4T was most closely related to the type strains of Lacticaseibacillus suibinensis and Lacticaseibacillus suilingensis, having 99.9% and 100% 16S rRNA gene sequence similarities, respectively, and that strains 419-1.2T and 262-4 were most closely related to the type strains of Companilactobacillus heilongjiangensis, Companilactobacillus nantensis, Companilactobacillus huachuanensis, and Companilactobacillus nuruki, having 98.5-99.7% 16S rRNA gene sequence similarities. The phylogenomic trees indicated that strain 74-4T was related to the type strains of L. suibinensis and L. suilingensis, and that strains 419-1.2T and 262-4 were related to the type strains of C. heilongjiangensis, C. nantensis, C. huachuanensis, and Companilactobacillus zhachilii. The ANI and dDDH values between strain 74-4T and type strains of phylogenetically related species were less than 92.7% and 49.9%, respectively. The ANI and dDDH values between strains 419-1.2T and 262-4 and type strains of phylogenetically related species were less than 93.4% and 51.7%, respectively. Based upon the data of polyphasic characterization obtained in the present study, two novel species, Lacticaseibacillus salsurivasis sp. nov. and Companilactobacillus muriivasis sp. nov., are proposed and the type strains are 74-4T (= JCM 35890T = CCTCC AB 2022414T) and 419-1.2T (= JCM 35891T = CCTCC AB 2022413T), respectively.


Assuntos
DNA Bacteriano , Filogenia , RNA Ribossômico 16S , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , China , Técnicas de Tipagem Bacteriana , Composição de Bases , Alimentos Fermentados/microbiologia , Análise de Sequência de DNA , Ácidos Graxos/análise , Microbiologia de Alimentos , Lacticaseibacillus
3.
Plant Dis ; 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326934

RESUMO

The small tree species Rhamnella franguloides, belonging to the genus Rhamnella in the tribe Rhamneae Hook. f. of Rhamnaceae (Hauenschild et al. 2016), is an important medicinal plant commonly used for making tea in China. In August 2023, leaf spot symptoms were observed on R. franguloides in Shangyao county, Yantai, Shandong, China, with a disease incidence of 45-65%. Initially appearing as small dark brown spots on the tip lesions, they later expanded and merged into irregular-shaped brown necrotic lesions with yellowish halos. To isolate pathogen, 20 symptomatic tissue fragments (5 × 5 mm) from ten sampling randomly plants were surface sterilized, placed on potato dextrose agar (PDA) plates, and incubated at 25°C in darkness for 3 days to obtain colonies.10 purified isolates with similar morphological characteristics were obtained by single-spore isolation from the colonies. The representative isolate MR13 was chosen for morphological and molecular analysis. The colonies On PDA medium initially appear as a circular yellow-brown ring with white round margins, ultimately turning into olive green with fluffy aerial hyphae. The conidiophores displayed brown pigmentation, solitary or branched, producing abundant short chains of conidia. The conidia were typically obclavate to obpyriform or ellipsoid in shape, 22.5-64.5 × 12.5-23.6µm in size, with a short conical beak at the apex, zero to three longitudinal septa and one to five transverse septa. Based on cultural and morphological characteristics, the fungus was identified as Alternaria spp (Simmons 2007). Due to morphological traits, five genes (the internal transcribed spacer [ITS], actin [ACT], plasma membrane ATPase [ATP], Alternaria major allergen [Alt a1] and histone 3 [H3]) form MR13 were amplified using primer pairs ITSI / ITS4, ACTDF1/R1, ATPDF1 / ATPDRI, Alt-for / Alt-rev, and H3-1a/1b, respectively (Hong et al. 2005; Lawrence et al. 2013; Lousie and Donaldson 1995). BLASTn analysis failed to confirm the identification of MR13 species based on ITS, ACT, ATP and Alt a1(ITS, OR668512; ACT, OR676918; ATP, OR676917; Alt a1, OR676919). The phylogenetic tree showed that it was closely related to Alternaria alternate, A. tenuissima, and A. destruens. The H3 sequence (OR676920) exhibited 100% similarity to A. tenuissima (OR485421). The phylogenetic tree constructed solely with H3 further confirmed MR13 as A. tenuissima. Pathogenicity tests were conducted by introducing the fungus onto healthy R. franguloides leaves in the field. Fifty leaves (five per plant) were treated with a 20ml suspension containing around 1x10^4 spores/ml, while an equal number of control samples were sprayed with distilled water. Transparent plastic bags were used to cover the treated leaves for 48 hours and maintain humidity. After fourteen days of inoculation, consistent leaf spotting symptoms were observed. In contrast, the control leaves showed no sign of infection. The fungal pathogen was successfully reisolated and identified as A. tenuissima through morphological and sequence analysis, fulfilling Koch's postulates. To our knowledge, this is the first report of A. tenuissima causing leaf spot disease on R. franguloides in China. Identifying the disease's causal agent is crucial for developing effective management strategies.

4.
Chemistry ; 29(37): e202300933, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37040176

RESUMO

Bulk chemical 2-methyl-2-butene, one of the main C5 distillates of the petrochemical industry, has scarcely been utilized directly in synthesizing high-value-added fine chemicals. Herein, we use 2-methyl-2-butene as the starting material to develop a palladium-catalyzed highly site- and regio-selective C-3 dehydrogenation reverse prenylation of indoles. This synthetic method features mild reaction conditions, a broad substrate scope, atom- and step-economies.

5.
J Magn Reson Imaging ; 58(5): 1590-1602, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-36661350

RESUMO

BACKGROUND: Dynamic contrast-enhanced (DCE) MRI and non-mono-exponential model-based diffusion-weighted imaging (NME-DWI) that does not require contrast agent can both characterize breast cancer. However, which technique is superior remains unclear. PURPOSE: To compare the performances of DCE-MRI, NME-DWI and their combination as multiparametric MRI (MP-MRI) in the prediction of breast cancer prognostic biomarkers and molecular subtypes based on radiomics. STUDY TYPE: Prospective. POPULATION: A total of 477 female patients with 483 breast cancers (5-fold cross-validation: training/validation, 80%/20%). FIELD STRENGTH/SEQUENCE: A 3.0 T/DCE-MRI (6 dynamic frames) and NME-DWI (13 b values). ASSESSMENT: After data preprocessing, high-throughput features were extracted from each tumor volume of interest, and optimal features were selected using recursive feature elimination method. To identify ER+ vs. ER-, PR+ vs. PR-, HER2+ vs. HER2-, Ki-67+ vs. Ki-67-, luminal A/B vs. nonluminal A/B, and triple negative (TN) vs. non-TN, the following models were implemented: random forest, adaptive boosting, support vector machine, linear discriminant analysis, and logistic regression. STATISTICAL TESTS: Student's t, chi-square, and Fisher's exact tests were applied on clinical characteristics to confirm whether significant differences exist between different statuses (±) of prognostic biomarkers or molecular subtypes. The model performances were compared between the DCE-MRI, NME-DWI, and MP-MRI datasets using the area under the receiver-operating characteristic curve (AUC) and the DeLong test. P < 0.05 was considered significant. RESULTS: With few exceptions, no significant differences (P = 0.062-0.984) were observed in the AUCs of models for six classification tasks between the DCE-MRI (AUC = 0.62-0.87) and NME-DWI (AUC = 0.62-0.91) datasets, while the model performances on the two imaging datasets were significantly poorer than on the MP-MRI dataset (AUC = 0.68-0.93). Additionally, the random forest and adaptive boosting models (AUC = 0.62-0.93) outperformed other three models (AUC = 0.62-0.90). DATA CONCLUSION: NME-DWI was comparable with DCE-MRI in predictive performance and could be used as an alternative technique. Besides, MP-MRI demonstrated significantly higher AUCs than either DCE-MRI or NME-DWI. EVIDENCE LEVEL: 2. TECHNICAL EFFICACY: Stage 2.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Estudos Prospectivos , Antígeno Ki-67 , Prognóstico , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos
6.
Molecules ; 28(6)2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36985470

RESUMO

5,6-Dihydrophenanthridines are common aza heterocycle frameworks of natural products and pharmaceuticals. Herein, we reported the first palladium-catalyzed intramolecular C-H/C-H dehydrogenative coupling reaction of two simple arenes to generate 5,6-dihydrophenanthridines. The approach features a broad substrate scope and good tolerance of functional groups, offering an efficient alternative synthesis route for important 5,6-dihydrophenanthridine compounds.

7.
Zhongguo Zhong Yao Za Zhi ; 48(11): 2925-2930, 2023 Jun.
Artigo em Zh | MEDLINE | ID: mdl-37381952

RESUMO

Based on the data of 56 kinds of diseases and drug use in 100 kinds of cultivated Chinese herbal medicines, this paper used frequency analysis method to count the types of diseases and their drug use characteristics, and systematically analyzed the status of drug registration and monitoring standards for disease prevention and control of Chinese herbal medicines. The results showed that 14 diseases such as root rot, powdery mildew, and drooping disease were common in the production of Chinese herbal medicines. Among the 99 pesticides reported, 67.68% were chemically synthesized, 23.23% were biological pesticides, and 9.09% were mineral pesticides. Among the reported pesticides, 92.93% of them were low toxic, with relative safety. However, 70% of the production drugs were not registered in Chinese herbal medicines, and the phenomenon of overdose was serious. The current pesticide residue monitoring standards does not match well with production drugs in China. Although the matching degree between Maximum Residue Limit of Pesticide in Food Safety National Standard(GB 2763-2021) and production drugs is more than 50%, there are few varieties of Chinese herbal medicines covered. The matching degree between Chinese Pharmacopoeia(2020 edition), Green Industry Standard of Medicinal Plants and Preparations(WM/T2-2004), and production drugs is only 1.28%. It is suggested to speed up the research and registration of Chinese herbal medicine production and further improve the pesticide residue limit standard combined with the actual production, so as to promote the high-quality development of Chinese herbal medicine industry.


Assuntos
Medicamentos de Ervas Chinesas , Resíduos de Praguicidas , Praguicidas , Humanos , Agentes de Controle Biológico
8.
Zhongguo Zhong Yao Za Zhi ; 48(12): 3281-3286, 2023 Jun.
Artigo em Zh | MEDLINE | ID: mdl-37382012

RESUMO

Pseudostellaria heterophylla in large-scale cultivation needs to apply pesticides to control diseases, and non-standard use of pesticide may cause excessive pesticide residues in medicinal materials, increasing the risk of clinical medication. To accurately monitor the residual pesticides, this paper investigated the drug use during the process of P. heterophylla disease prevention in 25 P. he-terophylla planting enterprises or individual households in Guizhou province. It was found that there were 8 common diseases in P. he-terophylla planting, including leaf spot, downy mildew, virus disease, root rot, dropping disease, purple feather disease, white silk disease, and damping-off disease. Twenty-three kinds of pesticides were used in disease control, mainly chemical synthetic pesticides, accounting for 78.3%, followed by biological pesticides and mineral pesticides, accounting for 13.0% and 8.7%, respectively. The disease prevention and control drugs were all low-toxic pesticides, and there were no varieties banned in the Chinese Pharmacopoeia(2020 edition). However, the pesticides used have not been registered on P. heterophylla, and the excessive use of drugs was serious. The present monitoring of pesticide residues in P. heterophylla is mainly based on traditional pesticides such as organochlorine, organophosphorus, and carbamate, which does not effectively cover the production of drugs and had certain safety risks. It is suggested to speed up the research and registration of drug use in the production of P. heterophylla, increase the use of biological pesticides, and further improve the monitoring indicators of pesticide residues in combination with the actual production of drugs, so as to promote the high-quality development of P. heterophylla industry.


Assuntos
Caryophyllaceae , Resíduos de Praguicidas , Praguicidas , Plantas Medicinais , Agentes de Controle Biológico
9.
Zhongguo Zhong Yao Za Zhi ; 48(6): 1491-1497, 2023 Mar.
Artigo em Zh | MEDLINE | ID: mdl-37005836

RESUMO

By investigating the contamination status and predicting the exposure risk of mycotoxin in Coicis Semen, we aim to provide guidance for the safety supervision of Chinese medicinal materials and the formulation(revision) of mycotoxin limit standards. The content of 14 mycotoxins in the 100 Coicis Semen samples collected from five major markets of Chinese medicinal materials in China was determined by UPLC-MS/MS. The probability evaluation model based on Monte Carlo simulation method was established after Chi-square test and One-way ANOVA of the sample contamination data. Health risk assessment was performed on the basis of margin of exposure(MOE) and margin of safety(MOS). The results showed that zearalenone(ZEN), aflatoxin B_1(AFB_1), deoxynivalenol(DON), sterigmatocystin(ST), and aflatoxin B_2(AFB_2) in the Coicis Semen samples had the detection rates of 84%, 75%, 36%, 19%, and 18%, and the mean contamination levels of 117.42, 4.78, 61.16, 6.61, and 2.13 µg·kg~(-1), respectively. According to the limit standards in the Chinese Pharmacopoeia(2020 edition), AFB_1, AFs and ZEN exceeded the standards to certain extents, with the over-standard rates of 12.0%, 9.0%, and 6.0%, respectively. The exposure risks of Coicis Semen to AFB_1, AFB2, ST, DON, and ZEN were low, while 86% of the samples were contaminated with two or more toxins, which needs more attention. It is suggested that the research on the combined toxicity of different mycotoxins should be strengthened to accelerate the cumulative exposure assessment of mixed contaminations and the formulation(revision) of toxin limit standards.


Assuntos
Coix , Micotoxinas , Humanos , Micotoxinas/análise , Aflatoxina B1/análise , Cromatografia Líquida/métodos , Contaminação de Alimentos/análise , Espectrometria de Massas em Tandem/métodos
10.
J Magn Reson Imaging ; 56(3): 848-859, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35064945

RESUMO

BACKGROUND: Dynamic-exponential intravoxel incoherent motion (IVIM) imaging is a potential technique for prediction, monitoring, and differential diagnosis of hepatic diseases, especially liver tumors. However, the use of such technique at voxel level is still limited. PURPOSE: To develop an unsupervised deep learning approach for voxel-wise dynamic-exponential IVIM modeling and parameter estimation in the liver. STUDY TYPE: Prospective. POPULATION: Ten healthy subjects (4 males; age 28 ± 6 years). FIELD STRENGTH/SEQUENCE: Single-shot spin-echo echo planar imaging (SE-EPI) sequence with monopolar diffusion-encoding gradients (12 b-values, 0-800 seconds/mm2 ) at 3.0 T. ASSESSMENT: The proposed deep neural network (DNN) was separately trained on simulated and in vivo hepatic IVIM datasets. The trained networks were compared to the approach combining least squares with Akaike information criterion (LSQ-AIC) in terms of dynamic-exponential modeling accuracy, inter-subject coefficients of variation (CVs), and fitting residuals on the simulated subsets and regions of interest (ROIs) in the left and right liver lobes. The ROIs were delineated by a radiologist (H.-X.Z.) with 7 years of experience in MRI reading. STATISTICAL TESTS: Comparisons between approaches were performed with a paired t-test (normality) or a Wilcoxon rank-sum test (nonnormality). P < 0.05 was considered statistically significant. RESULTS: In simulations, DNN gave significantly higher accuracy (91.6%-95.5%) for identification of bi-exponential decays with respect to LSQ-AIC (79.7%-86.8%). For tri-exponential identification, DNN was also superior to LSQ-AIC despite not reaching a significant level (P = 0.08). Additionally, DNN always yielded comparatively low root-mean-square error for estimated parameters. For the in vivo IVIM measurements, inter-subject CVs (0.011-0.150) of DNN were significantly smaller than those (0.049-0.573) of LSQ-AIC. Concerning fitting residuals, there was no significant difference between the two approaches (P = 0.56 and 0.76) in both the simulated and in vivo studies. DATA CONCLUSION: The proposed DNN is recommended for accurate and robust dynamic-exponential modeling and parameter estimation in hepatic IVIM imaging. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 1.


Assuntos
Aprendizado Profundo , Imagem de Difusão por Ressonância Magnética , Adulto , Imagem de Difusão por Ressonância Magnética/métodos , Humanos , Fígado/diagnóstico por imagem , Masculino , Movimento (Física) , Estudos Prospectivos , Reprodutibilidade dos Testes , Adulto Jovem
11.
J Magn Reson Imaging ; 55(3): 854-865, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34296813

RESUMO

BACKGROUND: Intravoxel incoherent motion (IVIM) tensor imaging is a promising technique for diagnosis and monitoring of cardiovascular diseases. Knowledge about measurement repeatability, however, remains limited. PURPOSE: To evaluate short-term repeatability of IVIM tensor imaging in normal in vivo human hearts. STUDY TYPE: Prospective. POPULATION: Ten healthy subjects without history of heart diseases. FIELD STRENGTH/SEQUENCE: Balanced steady-state free-precession cine sequence and single-shot spin-echo echo planar IVIM tensor imaging sequence (9 b-values, 0-400 seconds/mm2 and six diffusion-encoding directions) at 3.0 T. ASSESSMENT: Subjects were scanned twice with an interval of 15 minutes, leaving the scanner between studies. The signal-to-noise ratio (SNR) was evaluated in anterior, lateral, septal, and inferior segments of the left ventricle wall. Fractional anisotropy (FA), mean diffusivity (MD), mean fraction (MF), and helix angle (HA) in the four segments were independently measured by five radiologists. STATISTICAL TESTS: IVIM tensor indexes were compared between observers using a one-way analysis of variance or between scans using a paired t-test (normal data) or a Wilcoxon rank-sum test (non-normal data). Interobserver agreement and test-retest repeatability were assessed using the intraclass correlation coefficient (ICC), within-subject coefficient of variation (WCV), and Bland-Altman limits of agreements. RESULTS: SNR of inferior segment was significantly lower than the other three segments, and inferior segment was therefore excluded from repeatability analysis. Interobserver repeatability was excellent for all IVIM tensor indexes (ICC: 0.886-0.972; WCV: 0.62%-4.22%). Test-retest repeatability was excellent for MD of the self-diffusion tensor (D) and MF of the perfusion fraction tensor (fp ) (ICC: 0.803-0.888; WCV: 1.42%-9.51%) and moderate for FA and MD of the pseudo-diffusion tensor (D* ) (ICC: 0.487-0.532; WCV: 6.98%-10.89%). FA of D and fp and HA of D presented good test-retest repeatability (ICC: 0.732-0.788; WCV: 3.28%-8.71%). DATA CONCLUSION: The D and fp indexes exhibited satisfactory repeatability, but further efforts were needed to improve repeatability of D* indexes. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 1.


Assuntos
Imagem de Difusão por Ressonância Magnética , Imagem Ecoplanar , Imagem de Difusão por Ressonância Magnética/métodos , Imagem Ecoplanar/métodos , Voluntários Saudáveis , Humanos , Movimento (Física) , Estudos Prospectivos , Reprodutibilidade dos Testes
12.
Mol Pharm ; 19(2): 630-641, 2022 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-35034440

RESUMO

Combination treatments are more effective than conventional monotherapy in combating cancer. Herein, a multifunctional prodrug BDP-L-CPT was rationally engineered and prepared by the conjugation of a boron dipyrromethene (BDP)-based photosensitizer (PS) to the active site of the chemotherapeutic drug camptothecin (CPT) via a phenyl benzoate group. After modification, the cytotoxicity of CPT was locked. Moreover, the fluorescence emission at 430 nm from the CPT component in the prodrug was substantially inhibited through the intramolecular fluorescence resonance energy transfer process. The phenyl benzoate linker in BDP-L-CPT could be selectively cleaved by exogenous carboxylesterase in phosphate-buffered saline solution and endogenous carboxylesterase overexpressed in cancer cells, which was followed by self-immolation to release free CPT. The drug release process could be monitored by the turn-on of CPT fluorescence in solution and cells. Owing to the combination of site-specific chemotherapy with light-driven photodynamic therapy, the IC50 values of the prodrug BDP-L-CPT against HepG2 human hepatocellular carcinoma and HeLa human cervical carcinoma cells were lower than those of the controls, BDP-COOH and CPT. The combined antitumor effects of the prodrug BDP-L-CPT were also observed in the mice bearing H22 tumors. Furthermore, BDP-L-CPT had a more prolonged blood circulation time in mice than CPT, which is beneficial to persistent therapy. This study may provide a promising strategy for a selective combination cancer treatment by conjugating a prodrug to a PS.


Assuntos
Neoplasias Hepáticas , Fotoquimioterapia , Pró-Fármacos , Animais , Sítios de Ligação , Camptotecina/química , Linhagem Celular Tumoral , Neoplasias Hepáticas/tratamento farmacológico , Camundongos , Pró-Fármacos/química
13.
Int J Syst Evol Microbiol ; 72(12)2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36748700

RESUMO

Two Gram-stain-positive bacterial strains, designated 213-9(3)T and 30-1(2)T, were isolated from traditional Chinese pickle, and were characterized using a polyphasic taxonomic approach. Results of 16S rRNA gene sequence analysis indicated that strain 213-9(3)T was most closely related to Levilactobacillus paucivorans TMW 1.1424T, Levilactobacillus huananensis 151-2BT and Levilactobacillus lindianensis 220-4T, having 99.7-99.9 % 16S rRNA gene sequence similarities; strain 30-1(2)T was most closely related to Lapidilactobacillus achengensis 247-4T, with 99.4 % 16S rRNA gene sequence similarity. Strain 213-9(3)T shared the highest pheS (93.9 %), rpoA (99.3 %) and concatenated pheS and rpoA (97.5 %) sequence similarities to L. paucivorans TMW 1.1424T. Strain 30-1(2)T had the highest pheS (82.4 %), rpoA (95.5 %) and concatenated pheS and rpoA (91.2 %) sequence similarities to L. achengensis 247-4T. The phylogenetic relationships based on concatenated pheS and rpoA sequences and whole genome sequences were identical to those based on 16S rRNA gene sequences. Strain 213-9(3)T exhibited the highest average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values (92.7 and 48.8 %, respectively) to L. paucivorans DSM 22467T. Strain 30-1(2)T had the highest ANI (84.4 %) and dDDH (32.8 %) values with L. achengensis 247-4T. Acid production from d-galactose, d-glucose, d-mannose, N-acetyl-ß-glucosaminidase, arbutin, salicin, cellobiose, maltose, gentiobiose, d-tagatose and gluconate, hydrolysis of aesculin, and activity of cystine arylamidase could differentiate strain 213-9(3)T from L. paucivorans DSM 22467T. Acid production from l-arabinose, d-ribose, d-xylose and d-galactose, and activity of alkaline phosphatase, esterase (C4), α-mannosidase and α-fucosidase could differentiate strain 30-1(2)T from L. achengensis 247-4T. Based upon the data obtained in the present study, two novel species, Levilactobacillus humaensis sp. nov. and Lapidilactobacillus luobeiensis sp. nov., are proposed and the type strains are 213-9(3)T (=CCM 9241T=CCTCC AB 2022115T=JCM 35554T) and 30-1(2)T (=CCM 9240T=CCTCC AB 2022114T=JCM 35553T), respectively.


Assuntos
Alimentos Fermentados , Genes Bacterianos , Filogenia , RNA Ribossômico 16S/genética , Galactose , Ácidos Graxos/química , Análise de Sequência de DNA , Microbiologia de Alimentos , Composição de Bases , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Alimentos Fermentados/microbiologia , Hibridização de Ácido Nucleico
14.
Artigo em Inglês | MEDLINE | ID: mdl-35608970

RESUMO

A novel bifidobacteria (designated S053-2T) was isolated from the gut of honeybee (Apis mellifera). Strain S053-2T was characterized using a polyphasic taxonomic approach. The result of 16S rRNA gene sequence analysis indicated that strain S053-2T was phylogenetically related to the type strains of Bifidobacterium asteroides, Bifidobacterium indicum, Bifidobacterium actinocoloniiforme, Bifidobacterium xylocopae, Bifidobacterium coryneforme, Bifidobacterium apousia, Bifidobacterium choladohabitans and Bifidobacterium polysaccharolyticum, and had 95.5-99.7 % 16S rRNA gene sequence similarities. Based on the 16S rRNA gene sequence analysis, strain S053-2T was most closely related to the type strain of B. asteroides, having 99.7 % 16S rRNA gene sequence similarity. Strain S053-2T had relatively low (91.6-95.7 %) pheS, atpA, clpC, dnaG, fusA, glnA, glyS, hsp60, argS, pyrG and recA sequence similarities to the type strain of B. asteroides. Strain S053-2T had 94.5-95.3% atpA, clpC, dnaG, dnaK and pyrG sequence similarities to the type strain of B. apousia. The phylogenomic tree indicated that strain S053-2T belonged to the B. asteroides group, and was most closely related to the type strains of B. asteroides, B. apousia, B. choladohabitans and B. polysaccharolyticum, and distantly related to type strains of other phylogenetically related species in the B. asteroides group. Strain S053-2T shared the highest average nucleotide identity (ANI, 93.8 %), digital DNA-DNA hybridization (dDDH, 52.4 %) and average amino acid identity (AAI, 95.6%) values with B. apousia W8102T. Strain S053-2T shared 91.1 % ANI, 41.9 % dDDH and 92.5 % AAI values with B. asteroides DSM 20089T. Acid production from l-arabinose, d-xylose, d-mannose, amygdalin, cellobiose, maltose, melibiose, sucrose, raffinose, gentiobiose and l-fucose, and activity of esterase lipase (C8) and α-fucosidase could differentiate strain S053-2T from B. asteroides DSM 20089T. Acid production from d-mannose, maltose, sucrose, melezitose and gentiobiose, and activity of α-fucosidase could differentiate strain S053-2T from B. apousia W8102T. Based upon the data obtained in the present study, a novel species, Bifidobacterium mizhiense sp. nov., is proposed, and the type strain is S053-2T (=JCM 34710T=CCTCC AB 2021129T).


Assuntos
Manose , alfa-L-Fucosidase , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , Abelhas , Bifidobacterium , DNA Bacteriano/genética , Ácidos Graxos/química , Genes Bacterianos , Maltose , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Sacarose , alfa-L-Fucosidase/genética
15.
J Org Chem ; 87(10): 6573-6587, 2022 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-35522737

RESUMO

A new chemistry of azo compounds, that is, addition of free radicals generated in situ to access various acyl hydrazides, has been developed. The protocol provides a novel strategy for the synthesis of valuable acyl hydrazides. The transformation features mild reaction conditions, good tolerance of functional groups, and a broad substrate scope. In view of the importance of acyl hydrazides in functional materials and medicinal chemistry, this approach would find broad applications.


Assuntos
Ésteres , Hidrazinas , Ésteres/química , Radicais Livres , Hidrazinas/química
16.
Proc Natl Acad Sci U S A ; 116(21): 10447-10452, 2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-31061131

RESUMO

STAT3 is a transcription factor that plays central roles in various physiological processes, including differentiation of Th cells. Its deregulation results in serious diseases, including inflammatory diseases and cancer. The mechanisms related to how STAT3 activity is regulated remain enigmatic. Here we show that overexpression of FAM64A potentiates IL-6-induced activation of STAT3 and expression of downstream target genes, whereas deficiency of FAM64A has the opposite effects. FAM64A interacts with STAT3 in the nucleus and regulates binding of STAT3 to the promoters of its target genes. Deficiency of Fam64a significantly impairs differentiation of Th17 but not Th1 or induced regulatory T cells (iTreg). In addition, Fam64a deficiency attenuates experimental autoimmune encephalomyelitis (EAE) and dextran sulfate sodium (DSS)-induced colitis, which is correlated with decreased differentiation of Th17 cells and production of proinflammatory cytokines. Furthermore, Fam64a deficiency suppresses azoxymethane (AOM)/DSS-induced colitis-associated cancer (CAC) in mice. These findings suggest that FAM64A regulates Th17 differentiation and colitis and inflammation-associated cancer by modulating transcriptional activity of STAT3.


Assuntos
Carcinogênese/metabolismo , Colite/metabolismo , Fator de Transcrição STAT3/metabolismo , Células Th17 , Animais , Diferenciação Celular , Colite/complicações , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica , Camundongos
17.
Plant Dis ; 106(2): 748-750, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34726475

RESUMO

Peanut scorch spot caused by Leptosphaerulina arachidicola is one of the most severe leaf diseases of peanut that causes significant yield loss. Here, we report the first high-quality genome sequence of L. arachidicola JB313 isolated from an infected peanut leaf in China. The genome size is 47.66 Mb, consisting of 65 scaffolds (N50 length = 1.58 Mb) with a G+C content of 49.05%. The information in this report will provide a reference genome for future studies on the peanut scorch spot pathogen in peanut.


Assuntos
Arachis , Ascomicetos , Genoma Fúngico , Doenças das Plantas/microbiologia , Arachis/microbiologia , Ascomicetos/genética , China , Folhas de Planta
18.
Zhongguo Zhong Yao Za Zhi ; 47(12): 3320-3327, 2022 Jun.
Artigo em Zh | MEDLINE | ID: mdl-35851126

RESUMO

This study explored the effect and potential mechanism of Danlou Tablets(DLT) on insulin resistance in db/db mice with type 2 diabetic mellitus(T2 DM). The db/db male mice were randomly assigned into model control(MC) group, metformin(MET, tablet, 100 mg·kg~(-1)) group, and DLT(1 g·kg~(-1)) group, and C57 BL/6 J mice were taken as normal control(NC) group. The mice in the MET group and DLT group were given corresponding drugs by gavage once a day for 16 weeks. The fasting blood glucose, glucose tolerance, and insulin tolerance were measured to evaluate the effect of DLT on blood glucose and insulin resistance in diabetic mice. The serum free fatty acid, triacylglycerol, and total cholesterol levels were determined to evaluate the effect of DLT on blood lipids in diabetic mice. The liver index and perirenal fat index were calculated to measure the effect of DLT on lipid accumulation in non-adipose tissue and adipose tissue. Western blot was performed to determine the protein levels of insulin receptor-ß(IRß), phospho-IRß(p-IRß), phosphatidylinositol 3-kinase(PI3 K), and insulin receptor substrate-1(IRS-1) involved in IRS-1/PI3 K/Akt signaling pathway in the livers of mice to reveal the mechanism of DLT in alleviating insulin resistance in diabetic mice. The protein levels of sterol regulatory element binding protein-1(SREBP-1) and the mRNA levels of sterol regulatory element binding protein-1 c(SREBP-1 c), fatty acid synthase(FAS), acetyl-CoA carboxylase(ACC), diacylglycerol acyltransferase-1(Dgat1), and diacylglycerol acyltransferase-2(Dgat2) involved in the SREBP-1/FAS signaling pathway were detected to evaluate the effect of DLT on lipid metabolism in diabetic mice. Real-time quantitative PCR was employed to determine the mRNA levels of galectin-3(Gal-3), interleukin-6(IL-6), and monocyte chemoattractant protein-1(MCP-1) in mouse liver to evaluate the effect of DLT on inflammatory response in diabetic mice. The results showed that DLT significantly reduced the blood glucose and lipid levels and alleviated the insulin resistance in diabetic mice. Compared with the MC group, DLT significantly up-regulated the protein levels of p-IRß, PI3 K, and IRS-1(P<0.05 or P<0.01), and down-regulated the protein level of SREBP-1 in liver tissues of diabetic mice(P<0.05). DLT lowered the mRNA levels of SREBP-1 c, FAS, ACC, Dgat1, and Dgat2 related to lipid metabolism as well as those of Gal-3, IL-6, and MCP-1 associated with inflammation in the livers of diabetic mice(P<0.05 or P<0.01). The findings of this study suggest that DLT may alleviate insulin resistance in diabetic mice by regulating IRS-1/PI3 K/Akt signaling pathway and SREBP-1/FAS signaling pathway to reduce lipid production and inhibit inflammatory response.


Assuntos
Diabetes Mellitus Experimental , Resistência à Insulina , Adipogenia , Animais , Glicemia/metabolismo , Diabetes Mellitus Experimental/metabolismo , Diacilglicerol O-Aciltransferase/metabolismo , Diacilglicerol O-Aciltransferase/farmacologia , Medicamentos de Ervas Chinesas , Insulina/metabolismo , Interleucina-6/metabolismo , Lipídeos , Fígado , Masculino , Camundongos , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo
19.
Zhongguo Zhong Yao Za Zhi ; 47(3): 628-634, 2022 Feb.
Artigo em Zh | MEDLINE | ID: mdl-35178944

RESUMO

This study aimed to establish a method for synchronous detection of 14 mycotoxins in Pseudostellariae Radix and investigate its contamination with mycotoxins, so as to provide technical guidance for monitoring the quality of Chinese medicinal materials and medication safety. The sample was extracted with 80% acetonitrile in an oscillator for 1 h, purified using the modified QuEChERS purifying agent(0.1 g PSA + 0.3 g C_(18) + 0.3 g MgSO_4), and separated on a Waters HSS T3 chromatographic column(2.1 mm×100 mm, 1.8 µm). The gradient elution was carried out with 0.1% formic acid in water and acetonitrile, followed by the scanning in the multi-reaction monitoring(MRM) mode and the analysis of mycotoxin contamination in 26 Pseudostellariae Radix samples. The recovery rates of the established method were within the range of 82.17%-113.6%, with the RSD values less than 7% and the limits of quantification(LOQ) being 0.019-0.976 µg·kg~(-1). The detection rate of 14 mycotoxins in 26 batches of medicinal materials was 53.85%. The detection rate of sterigmatocystin(ST) was the highest, followed by those of zearalenone(ZEN), aflatoxin G_2(AFG_2), fumonisin B_1(FB_1), HT-2 toxin, and nivalenol(NIV). Their respective detection rates were 38.46%, 26.92%, 23.08%, 11.54%, 11.54%, and 7.69%, with the pollution ranges being 1.48-69.65, 0.11-31.05, 0.11-0.66, 0.28-0.83, 20.86-42.56, and 0.46-1.84 µg·kg~(-1), respectively. The established method for the detection of 14 mycotoxins is accurate, fast and reliable. The research results have very important practical significance for guiding the monitoring and prevention and control of exogenous fungal contamination of Chinese medicinal materials.


Assuntos
Aflatoxinas , Micotoxinas , Aflatoxinas/análise , Cromatografia Líquida de Alta Pressão/métodos , Contaminação de Medicamentos , Contaminação de Alimentos/análise , Micotoxinas/análise , Raízes de Plantas/química , Espectrometria de Massas em Tandem/métodos
20.
Angew Chem Int Ed Engl ; 61(10): e202117661, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35034424

RESUMO

Covalent organic frameworks (COF) possess a robust and porous crystalline structure, making them an appealing candidate for energy storage. Herein, we report an exfoliated polyimide COF composite (P-COF@SWCNT) prepared by an in situ condensation of anhydride and amine on the single-walled carbon nanotubes as advanced anode for potassium-ion batteries (PIBs). Numerous active sites exposed on the exfoliated frameworks and the various open pathways promote the highly efficient ion diffusion in the P-COF@SWCNT while preventing irreversible dissolution in the electrolyte. During the charging/discharging process, K+ is engaged in the carbonyls of imide group and naphthalene rings through the enolization and π-K+ effect, which is demonstrated by the DFT calculation and XPS, ex-situ FTIR, Raman. As a result, the prepared P-COF@SWCNT anode enables an incredibly high reversible specific capacity of 438 mA h g-1 at 0.05 A g-1 and extended stability. The structural advantage of P-COF@SWCNT enables more insights into the design and versatility of COF as an electrode.

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