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1.
Plant Biotechnol J ; 16(12): 2088-2101, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29734518

RESUMO

Sequence-specific nucleases have been used to engineer targeted genome modifications in various plants. While targeted gene knockouts resulting in loss of function have been reported with relatively high rates of success, targeted gene editing using an exogenously supplied DNA repair template and site-specific transgene integration has been more challenging. Here, we report the first application of zinc finger nuclease (ZFN)-mediated, nonhomologous end-joining (NHEJ)-directed editing of a native gene in allohexaploid bread wheat to introduce, via a supplied DNA repair template, a specific single amino acid change into the coding sequence of acetohydroxyacid synthase (AHAS) to confer resistance to imidazolinone herbicides. We recovered edited wheat plants having the targeted amino acid modification in one or more AHAS homoalleles via direct selection for resistance to imazamox, an AHAS-inhibiting imidazolinone herbicide. Using a cotransformation strategy based on chemical selection for an exogenous marker, we achieved a 1.2% recovery rate of edited plants having the desired amino acid change and a 2.9% recovery of plants with targeted mutations at the AHAS locus resulting in a loss-of-function gene knockout. The latter results demonstrate a broadly applicable approach to introduce targeted modifications into native genes for nonselectable traits. All ZFN-mediated changes were faithfully transmitted to the next generation.


Assuntos
Edição de Genes/métodos , Genes de Plantas/genética , Triticum/genética , Dedos de Zinco/genética , Reparo do DNA/genética , Genoma de Planta/genética , Poliploidia
2.
Fungal Genet Biol ; 80: 31-42, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25937438

RESUMO

Although ribosomal proteins (RPs) are components of the ribosome, and function centrally in protein synthesis, several lines of evidence suggest that S4 ribosomal proteins (Rps4ps) can function in other cellular roles. In Candida albicans, ribosomal protein S4 (Rps4p) is encoded by two distinct but highly similar genes, RPS41 (C2_10620W_A) and RPS42 (C1_01640W_A). Previous studies indicated that in Saccharomyces cerevisiae loss of one isoform generated distinct phenotypes. To probe this relationship in C. albicans, rps41Δ and rps42Δ homozygous null mutants were generated. The transcript levels of the RPS41 and RPS42 genes are asymmetric in C. albicans, RPS41 mRNA levels were similar in wild-type strains and rps42Δ null mutants, while RPS42 gene transcript levels were induced 20 fold relative to wild type in rps41Δ null mutants. We found that the rps41Δ homozygous null mutant showed a reduced growth rate, and had defects in filament formation in liquid media and on solid media, while these phenotypes were not observed in the rps42Δ mutant strain. Neither the rps41Δ nor rps42Δ mutant strains displayed differential sensitivity to azoles, although intriguingly ectopic expression of either RPS41 or RPS42 in a wild-type strain leads to decreased sensitivity to fluconazole (FLC). C. albicans cDNA microarray analysis experiments found that carbohydrate and nitrogen metabolic processes were repressed but transport-process-related genes were up-regulated in the rps41Δ mutant. Overall, our present study suggests that loss of the RPS41 gene but not its paralog the RPS42 gene can generate distinct phenotypes including effects on growth rate, morphological transitions, and susceptibility to osmotic stress due to the fact that mRNA levels of RPS41 is much higher than RPS42 in C. albicans.


Assuntos
Candida albicans/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Candida albicans/fisiologia , Fluconazol/farmacologia , Fungos/genética , Fungos/fisiologia , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Mutação , Pressão Osmótica , Fenótipo , RNA Mensageiro/metabolismo , Transcriptoma/efeitos dos fármacos
3.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(4): 990-3, 2014 Apr.
Artigo em Zh | MEDLINE | ID: mdl-25007615

RESUMO

A novel facile method for on-site detection of antipertensive chemicals (e. g. nicardipine hydrochloride, doxazosin mesylate, propranolol hydrochloride, and hydrochlorothiazide) adulterated in traditional Chinese medicine for hypertension using thin layer chromatography (TLC) combined with surface enhanced Raman spectroscopy (SERS) was reported in the present paper. Analytes and pharmaceutical matrices was separated by TLC, then SERS method was used to complete qualitative identification of trace substances on TLC plate. By optimizing colloidal silver concentration and developing solvent, as well as exploring the optimal limits of detection (LOD), the initially established TLC-SERS method was used to detect real hypertension Chinese pharmaceuticals. The results showed that this method had good specificity for the four chemicals and high sensitivity with a limit of detection as lower as to 0.005 microg. Finally, two of the ten antipertensive drugs were detected to be adulterated with chemicals. This simple and fast method can realize rapid detection of chemicals illegally for doping in antipertensive Chinese pharmaceuticals, and would have good prospects in on-site detection of chemicals for doping in Chinese pharmaceuticals.


Assuntos
Anti-Hipertensivos/análise , Cromatografia em Camada Fina , Contaminação de Medicamentos , Medicamentos de Ervas Chinesas/análise , Limite de Detecção , Sensibilidade e Especificidade , Análise Espectral Raman
4.
Artigo em Inglês | MEDLINE | ID: mdl-38429161

RESUMO

Metabolic dysfunction-associated steatotic liver disease (MASLD) has emerged as the most common chronic liver disease globally, affecting more than a third of the world's adult population. This comprehensive narrative review summarizes the global incidence and prevalence rates of MASLD and its related adverse hepatic and extrahepatic outcomes. We also discuss the substantial economic burden of MASLD on healthcare systems, thus further highlighting the urgent need for global efforts to tackle this common and burdensome liver condition. We emphasize the clinical relevance of early interventions and a holistic approach that includes public health strategies to reduce the global impact of MASLD.

5.
World J Radiol ; 16(6): 211-220, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38983836

RESUMO

BACKGROUND: Solid pseudopapillary neoplasms of the pancreas (SPN) share similar imaging findings with pancreatic ductal adenocarcinoma with cystic changes (PDAC with cystic changes), which may result in unnecessary surgery. AIM: To investigate the value of computed tomography (CT) in differentiation of SPN from PDAC with cystic changes. METHODS: This study retrospectively analyzed the clinical and imaging findings of 32 patients diagnosed with SPN and 14 patients diagnosed with PDAC exhibiting cystic changes, confirmed through pathological diagnosis. Quantitative and qualitative analysis was performed, including assessment of age, sex, tumor size, shape, margin, density, enhancement pattern, CT values of tumors, CT contrast enhancement ratios, "floating cloud sign," calcification, main pancreatic duct dilatation, pancreatic atrophy, and peripancreatic invasion or distal metastasis. Multivariate logistic regression analysis was used to identify relevant features to differentiate between SPN and PDAC with cystic changes, and receiver operating characteristic curves were obtained to evaluate the diagnostic performance of each variable and their combination. RESULTS: When compared to PDAC with cystic changes, SPN had a lower age (32 years vs 64 years, P < 0.05) and a slightly larger size (5.41 cm vs 3.90 cm, P < 0.05). SPN had a higher frequency of "floating cloud sign" and peripancreatic invasion or distal metastasis than PDAC with cystic changes (both P < 0.05). No significant difference was found with respect to sex, tumor location, shape, margin, density, main pancreatic duct dilatation, calcification, pancreatic atrophy, enhancement pattern, CT values of tumors, or CT contrast enhancement ratios between the two groups (all P > 0.05). The area under the receiver operating characteristic curve of the combination was 0.833 (95% confidence interval: 0.708-0.957) with 78.6% sensitivity, 81.3% specificity, and 80.4% accuracy in differentiation of SPN from PDAC with cystic changes. CONCLUSION: A larger tumor size, "floating cloud sign," and peripancreatic invasion or distal metastasis are useful CT imaging features that are more common in SPN and may help discriminate SPN from PDAC with cystic changes.

6.
World J Gastrointest Oncol ; 16(4): 1256-1267, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38660647

RESUMO

BACKGROUND: One of the primary reasons for the dismal survival rates in pancreatic ductal adenocarcinoma (PDAC) is that most patients are usually diagnosed at late stages. There is an urgent unmet clinical need to identify and develop diagnostic methods that could precisely detect PDAC at its earliest stages. AIM: To evaluate the potential value of radiomics analysis in the differentiation of early-stage PDAC from late-stage PDAC. METHODS: A total of 71 patients with pathologically proved PDAC based on surgical resection who underwent contrast-enhanced computed tomography (CT) within 30 d prior to surgery were included in the study. Tumor staging was performed in accordance with the 8th edition of the American Joint Committee on Cancer staging system. Radiomics features were extracted from the region of interest (ROI) for each patient using Analysis Kit software. The most important and predictive radiomics features were selected using Mann-Whitney U test, univariate logistic regression analysis, and minimum redundancy maximum relevance (MRMR) method. Random forest (RF) method was used to construct the radiomics model, and 10-times leave group out cross-validation (LGOCV) method was used to validate the robustness and reproducibility of the model. RESULTS: A total of 792 radiomics features (396 from late arterial phase and 396 from portal venous phase) were extracted from the ROI for each patient using Analysis Kit software. Nine most important and predictive features were selected using Mann-Whitney U test, univariate logistic regression analysis, and MRMR method. RF method was used to construct the radiomics model with the nine most predictive radiomics features, which showed a high discriminative ability with 97.7% accuracy, 97.6% sensitivity, 97.8% specificity, 98.4% positive predictive value, and 96.8% negative predictive value. The radiomics model was proved to be robust and reproducible using 10-times LGOCV method with an average area under the curve of 0.75 by the average performance of the 10 newly built models. CONCLUSION: The radiomics model based on CT could serve as a promising non-invasive method in differential diagnosis between early and late stage PDAC.

7.
Hepatol Int ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594474

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is one of the most common chronic liver diseases worldwide. In recent years, a new terminology and definition of metabolic dysfunction-associated fatty liver disease (MAFLD) has been proposed. Compared to the NAFLD definition, MAFLD better emphasizes the pathogenic role of metabolic dysfunction in the development and progression of this highly prevalent condition. Metabolic disorders, including overweight/obesity, type 2 diabetes mellitus (T2DM), atherogenic dyslipidemia and hypertension, are often associated with systemic organ dysfunctions, thereby suggesting that multiple organ damage can occur in MAFLD. Substantial epidemiological evidence indicates that MAFLD is not only associated with an increased risk of liver-related complications, but also increases the risk of developing several extra-hepatic diseases, including new-onset T2DM, adverse cardiovascular and renal outcomes, and some common endocrine diseases. We have summarized the current literature on the adverse effect of MAFLD on the development of multiple extrahepatic (cardiometabolic and endocrine) complications and examined the role of different metabolic pathways and organ systems in the progression of MAFLD, thus providing new insights into the role of MAFLD as a multisystem metabolic disorder. Our narrative review aimed to provide insights into potential mechanisms underlying the known associations between MAFLD and extrahepatic diseases, as part of MAFLD as a multisystem disease, in order to help focus areas for future drug development targeting not only liver disease but also the risk of extrahepatic complications.

8.
Mol Divers ; 17(3): 515-24, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23703159

RESUMO

The effects of Salvianolic acid A (Sal A) on the treatment of Alzheimer's disease (AD) were investigated. Sal A significantly inhibits amyloid beta [Formula: see text] self-aggregation and disaggregates pre-formed [Formula: see text] fibrils, reduces metal-induced [Formula: see text] aggregation through chelating metal ions, and blocks the formation of reactive oxygen species (ROS) in SH-SY5Y cells. Sal A protects cells against [Formula: see text]-induced toxicity. Furthermore, Sal A, possibly because of the effects of decreasing toxicity effects of [Formula: see text] species, alleviates [Formula: see text]-induced paralysis in transgenic Caenorhabditis elegans. Circular dichroism (CD) experiments and Molecular dynamic (MD) simulations demonstrate that Sal A inhibits [Formula: see text] self-aggregation through binding to the C-terminus of [Formula: see text], and therefore stabilizing the [Formula: see text]-helical conformations. Altogether, our data show that Sal A, as the multifunctional agent, is likely to be promising therapeutics for AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/efeitos dos fármacos , Ácidos Cafeicos/farmacologia , Lactatos/farmacologia , Placa Amiloide/tratamento farmacológico , Proteína Amiloide A Sérica/efeitos dos fármacos , Animais , Caenorhabditis elegans/efeitos dos fármacos , Linhagem Celular Tumoral , Dicroísmo Circular , Cobre/química , Avaliação Pré-Clínica de Medicamentos , Humanos , Ferro/química , Quelantes de Ferro , Simulação de Dinâmica Molecular , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Espécies Reativas de Oxigênio/antagonistas & inibidores , Salvia miltiorrhiza , Proteína Amiloide A Sérica/metabolismo , Zinco/química
9.
World J Gastrointest Oncol ; 15(6): 1051-1061, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37389113

RESUMO

BACKGROUND: Intrapancreatic accessory spleen (IPAS) shares similar imaging findings with hypervascular pancreatic neuroendocrine tumors (PNETs), which may lead to unnecessary surgery. AIM: To investigate and compare the diagnostic performance of absolute apparent diffusion coefficient (ADC) and normalized ADC (lesion-to-spleen ADC ratios) in the differential diagnosis of IPAS from PNETs. METHODS: A retrospective study consisting of 29 patients (16 PNET patients vs 13 IPAS patients) who underwent preoperative contrast-enhanced magnetic resonance imaging together with diffusion-weighted imaging/ADC maps between January 2017 and July 2020 was performed. Two independent reviewers measured ADC on all lesions and spleens, and normalized ADC was calculated for further analysis. The receiver operating characteristics analysis was carried out for evaluating the diagnostic performance of both absolute ADC and normalized ADC values in the differential diagnosis between IPAS and PNETs by clarifying sensitivity, specificity, and accuracy. Inter-reader reliability for the two methods was evaluated. RESULTS: IPAS had a significantly lower absolute ADC (0.931 ± 0.773 × 10-3 mm2/s vs 1.254 ± 0.219 × 10-3 mm2/s) and normalized ADC value (1.154 ± 0.167 vs 1.591 ± 0.364) compared to PNET. A cutoff value of 1.046 × 10-3 mm2/s for absolute ADC was associated with 81.25% sensitivity, 100% specificity, and 89.66% accuracy with an area under the curve of 0.94 (95% confidence interval: 0.8536-1.000) for the differential diagnosis of IPAS from PNET. Similarly, a cutoff value of 1.342 for normalized ADC was associated with 81.25% sensitivity, 92.31% specificity, and 86.21% accuracy with an area under the curve of 0.91 (95% confidence interval: 0.8080-1.000) for the differential diagnosis of IPAS from PNET. Both methods showed excellent inter-reader reliability with intraclass correlation coefficients for absolute ADC and ADC ratio being 0.968 and 0.976, respectively. CONCLUSION: Both absolute ADC and normalized ADC values can facilitate the differentiation between IPAS and PNET.

10.
Digit Health ; 9: 20552076231179007, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37312938

RESUMO

Background: Diagnosis of pancreatic ductal adenocarcinoma (PDAC) is difficult due to the lack of specific symptoms and screening methods. Only less than 10% of PDAC patients are candidates for surgery at the time of diagnosis. Thus, there is a great global unmet need for valuable biomarkers that could improve the opportunity to detect PDAC at the resectable stage. This study aimed to develop a potential biomarker model for the detection of resectable PDAC by tissue and serum metabolomics. Methods: Ultra-high-performance liquid chromatography and quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS/MS) was performed for metabolome quantification in 98 serum samples (49 PDAC patients and 49 healthy controls (HCs)) and 20 pairs of matched pancreatic cancer tissues (PCTs) and adjacent noncancerous tissues (ANTs) from PDAC patients. Univariate and multivariate analyses were used to profile the differential metabolites between PDAC and HC. Results: A total of 12 differential metabolites were present in both serum and tissue samples of PDAC. Among them, a total of eight differential metabolites showed the same expressional levels, including four upregulated and four downregulated metabolites. Finally, a panel of three metabolites including 16-hydroxypalmitic acid, phenylalanine, and norleucine was constructed by logistic regression analysis. Notably, the panel was capable of distinguishing resectable PDAC from HC with an AUC value of 0.942. Additionally, a multimarker model based on the 3-metabolites-based panel and CA19-9 showed a better performance than the metabolites panel or CA19-9 alone (AUC: 0.968 vs. 0.942, 0.850). Conclusions: Taken together, the resectable early-stage PDAC has unique metabolic features in serum and tissue samples. The defined panel of three metabolites has the potential value for early screening of PDAC at the resectable stage.

11.
Biol Pharm Bull ; 34(5): 624-31, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21532148

RESUMO

Genome plasticity is a hallmark of Candida albicans and is believed to be an adaptation strategy. But the extent of such genomic variability is not well investigated. In this study, genetic contents of clinical C. albicans isolates were investigated at whole-genome level with array-based comparative genomic hybridization (array CGH) technology. It was revealed that C. albicans possessed variations of genetic contents, as well as aneuploidy. The variable genes were scattered across the chromosomes, as well clustered in particular regions, including sub-telomeric regions, retrotransposon-insertion sites and a variable region on chromosome 6.


Assuntos
Candida albicans/genética , Adaptação Fisiológica/genética , Sequência de Bases , Candida albicans/isolamento & purificação , Candida albicans/fisiologia , Cromossomos Fúngicos , Hibridização Genômica Comparativa , Primers do DNA , Dosagem de Genes , Genes Fúngicos , Fases de Leitura Aberta , Reação em Cadeia da Polimerase , Retroelementos
12.
J Clin Transl Hepatol ; 9(5): 626-634, 2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34722177

RESUMO

BACKGROUND AND AIMS: Acute-on-chronic liver failure (ACLF) is acute decompensation of liver function in the setting of chronic liver disease, and characterized by high short-term mortality. In this study, we sought to investigate the clinical course of patients at specific time points, and to propose dynamic prognostic criteria. METHODS: We assessed the clinical course of 453 patients with ACLF during a 12-week follow-up period in this retrospective multicenter study. The clinical course of patients was defined as disease recovery, improvement, worsening or steady patterns based on the variation tendency in prothrombin activity (PTA) and total bilirubin (TB) at different time points. RESULTS: Resolution of PTA was observed in 231 patients (51%) at 12 weeks after the diagnosis of ACLF. Among the remaining patients, 66 (14.6%) showed improvement and 156 (34.4%) showed a steady or worsening course. In patients with resolved PTA, the clinical course of TB exhibited resolved pattern in 95.2%, improved in 3.9%, and steady or worse in 0.8%. Correspondingly, in patients with improved PTA, these values for TB were 28.8%, 27.3%, and 43.9%, respectively. In patients with steady or worsening PTA, these values for TB were 5.7%, 32.3%, and 65.6%, respectively. Dynamic prognostic criteria were developed by combining the clinical course of PTA/TB and the clinical outcomes at 4 and 12 weeks after diagnosis in ACLF patients. CONCLUSIONS: We propose the following dynamic prognostic criteria: rapid progression, slow progression, rapid recovery, slow recovery, and slow persistence, which lay the foundation for precise prediction of prognosis and the improvement of ACLF therapy.

13.
Front Chem ; 8: 581, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32850623

RESUMO

Bladder cancer is one of the most malignant tumors closely associated with macrophage immune dysfunction. The Chinese medicine polyporus has shown excellent efficacy in treating bladder cancer, with minimal side effects. However, its material basis and mechanism of action remain unclear. A new water-soluble polysaccharide (HPP) with strong immunomodulatory activity was isolated from the fungus Polyporus umbellatus (Pers.) Fries. HPP had an average molecular weight of 6.88 kDa and was composed mainly of an <-(1 → 4)-linked D-galactan backbone. The immunomodulatory activity of HPP was determined in vitro, and the results revealed that it could obviously increase the secretion of immune factors by IFN-γ-stimulated macrophages, including nitric oxide (NO), interleukin-6 (IL-6), interleukin-1ß (IL-1ß), RANTES and interleukin-23 (IL-23), and the expression of the cell membrane molecule CD80. In addition, HPP was recognized by Toll-like receptor 2 (TLR2) and activated the signaling pathways of NF-κB and NLRP3 in a bladder cancer microenvironment model, indicating that HPP could enhance host immune system function. These findings demonstrated that HPP may be a potential immune modulator in the treatment of immunological diseases or bladder cancer therapy.

14.
Clin Exp Pharmacol Physiol ; 36(10): e40-6, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19413603

RESUMO

1. The aim of the present study was to investigate the effects of ascorbic acid (AA) on the antifungal activity of fluconazole (FCZ) in a systemic murine candidiasis model as well as in vitro. 2. The murine model was established by infusion of Candida albicans via the tail vein. Control mice received no further treatment. Other groups of mice were injected with FCZ (0.5 mg/kg, i.p.) and then treated or not with 50 or 500 mg/kg AA intragastrically (i.g.) or i.p. In all groups, FCZ was administered i.p. 2 h after fungal inoculation, whereas AA was administered 6 h after fungal inoculation. Survival rate, kidney fungal burden and renal pathological changes were evaluated. 3. The in vitro effects of AA (5, 1 and 0.2 mmol/L) on the growth of various Candida strains in the presence of FCZ (0.125-64 microg/mL) were also investigated. The in vitro effects of two anti-oxidants, namely N-acetylcysteine (NAC; 5, 1 and 0.2 mmol/L) and reduced glutathione (GSH; 5, 1 and 0.2 mmol/L), on FCZ activity were evaluated to determine the mechanism of action of AA. 4. Intragastric administration of AA (50 or 500 mg/kg) significantly decreased the antifungal effect of 0.5 mg/kg FCZ. Although i.p. administration of AA (50 or 500 mg/kg) had no significant effect on the survival of mice, it dose-dependently inhibited the activity of FCZ, with significant inhibition observed with 500 mg/kg AA. 5. In vitro, AA decreased the activity of FCZ against various Candida strains. Both NAC and GSH dose-dependently decreased the activity of FCZ. 6. The results of the present study indicate that AA inhibits the antifungal activity of FCZ, suggesting that the two should not be used together clinically for the treatment of candidiasis.


Assuntos
Antifúngicos/uso terapêutico , Ácido Ascórbico/farmacologia , Candidíase/tratamento farmacológico , Fluconazol/uso terapêutico , Animais , Antifúngicos/farmacologia , Antioxidantes/farmacologia , Candida albicans/efeitos dos fármacos , Candidíase/mortalidade , Modelos Animais de Doenças , Antagonismo de Drogas , Avaliação Pré-Clínica de Medicamentos , Farmacorresistência Fúngica/efeitos dos fármacos , Fluconazol/farmacologia , Camundongos , Testes de Sensibilidade Microbiana
15.
J Microbiol Biotechnol ; 19(8): 803-9, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19734718

RESUMO

Recent evidence has revealed the occurrence of an apoptotic phenotype in Candida albicans that is inducible with environmental stresses such as acetic acid, hydrogen peroxide, and amphotericin B. In the present study, we found that the Chinese herbal medicine Baicalein (BE), which was one of the skullcapflavones, can induce apoptosis in C. albicans. The apoptotic effects of BE were detected by flow cytometry using Annexin V-FITC and DAPI, and it was confirmed by transmission electron microscopy analysis. After exposure to 4 microg/ml BE for 12 h, about 10% of C. albicans cells were apoptotic. Both the increasing intracellular levels of reactive oxygen species (ROS) and upregulation of some redox-related genes (CAP1, SOD2, TRR1) were observed. Furthermore, we compared the survivals of CAP1 deleted, wild-type, and overexpressed strains and found that Cap1p attenuated BE-initiated cell death, which was coherent with a higher mRNA level of the CAP1 gene. In addition, the mitochondrial membrane potential of C. albicans cells changed significantly ( p<0.001) upon BE treatment compared with control. Taken together, our results indicate that BE treatment induces apoptosis in C.albicans cells, and the apoptosis was associated with the breakdown of mitochondrial membrane potential.


Assuntos
Antioxidantes/administração & dosagem , Apoptose/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Flavanonas/administração & dosagem , Fatores de Transcrição de Zíper de Leucina Básica , Candida albicans/fisiologia , Candida albicans/ultraestrutura , Candidíase/tratamento farmacológico , Candidíase/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Genes Fúngicos , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Microscopia Eletrônica de Transmissão , RNA Fúngico/biossíntese , RNA Fúngico/genética , Espécies Reativas de Oxigênio/metabolismo , Regulação para Cima
16.
Biochem Biophys Res Commun ; 373(4): 631-6, 2008 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-18601908

RESUMO

Widespread and repeated use of azoles, particularly fluconazole, has led to the rapid development of azole resistance in Candida albicans. Overexpression of CDR1, CDR2, and CaMDR1 has been reported contributing to azole resistance in C. albicans. In this study, hyper-resistant C. albicans mutant, with the above three genes deleted, was obtained by exposure to fluconazole and fluphenezine for 28 passages. Thirty-five differentially expressed genes were identified in the hyper-resistant mutant by microarray analysis; among the 13 up-regulated genes, we successfully constructed the rta2 and ipf14030 null mutants in C. albicans strain with deletions of CDR1, CDR2 and CaMDR1. Using spot dilution assay, we demonstrated that the disruption of RTA2 increased the susceptibility of C. albicans to azoles while the disruption of IPF14030 did not influence the sensitivity of C. albicans to azoles. Meanwhile, we found that ectopic overexpression of RTA2 in C. albicans strain with deletions of CDR1, CDR2 and CaMDR1 conferred resistance to azoles. RTA2 expression was found elevated in clinical azole-resistant isolates of C. albicans. In conclusion, our findings suggest that RTA2 is involved in the development of azole resistance in C. albicans.


Assuntos
Antifúngicos/farmacologia , Azóis/farmacologia , Farmacorresistência Fúngica/genética , Proteínas Fúngicas/fisiologia , Proteínas de Membrana/fisiologia , Candida albicans/efeitos dos fármacos , Candida albicans/genética , Fluconazol/farmacologia , Proteínas Fúngicas/genética , Genes Fúngicos , Proteínas de Membrana/genética , Testes de Sensibilidade Microbiana , Análise de Sequência com Séries de Oligonucleotídeos
17.
J Ethnopharmacol ; 115(1): 1-8, 2008 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-17964746

RESUMO

The study was aimed to investigate the effects and mechanism of action of Changtai granule (CT), a traditional compound Chinese medicinal formula, in rodent 2,4,6-trinitrobenzene sulfonic acid (TNBS) colitis. Rats with TNBS/ethanol-induced colitis were used. The colonic wet weight, myeloperoxidase (MPO) activity, macroscopic and histological colon injury was observed. Inflammation cytokines were determined by ELISA methods and semi-quantitative RT-PCR. When dosed orally once daily, CT markedly attenuated TNBS-induced colitis. CT significantly attenuated colonic wet weight, macroscopic and histological colon injury. CT decreased mucosal mRNA levels for several inflammatory mediators: inducible nitric oxide synthase, cyclooxygenase 2, and macrophage inflammatory protein 2. CT also decreased mucosal mRNA and protein levels of T effectors cytokines: tumor necrosis factor-alpha (TNF-alpha), interleukin-2 (IL-2) and interferon-gamma (IFN-gamma). Systemic levels of these cytokines were also dramatically attenuated. CD3/CD28-mediated costimulation of T helper 1 effector cytokines release in lamina propria mononuclear cells (LPMC) was markedly inhibited by CT ex vivo and in vitro. Also CT prevented cytokines production by nuclear factor-kappaB (NF-kappaB). The potential anti-inflammatory and immunomodulatory effect of CT in TNBS colitis suggests that CT may be an effective treatment approach for inflammatory bowel disease.


Assuntos
Colite/tratamento farmacológico , Inflamação/tratamento farmacológico , Preparações de Plantas/farmacologia , Animais , Colite/induzido quimicamente , Colite/imunologia , Ensaio de Imunoadsorção Enzimática , Euphorbia/química , Haptenos , Inflamação/etiologia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Masculino , Medicina Tradicional Chinesa , Phellodendron/química , Polygonum/química , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sanguisorba/química , Ácido Trinitrobenzenossulfônico
18.
Front Biosci ; 12: 145-53, 2007 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-17127290

RESUMO

Cap1p, a transcription factor in Candida albicans, is believed to be required for tolerance to oxidative stress. However, no information is available concerning its function on basal transcriptional profile. In this study, differentially expressed genes between the CAP1-deleted strain and its parental strain under normal culture condition were identified through microarray analysis. Notably, among the 48 down-regulated genes with the deletion of CAP1, there were three clusters, functionally related to intracellular redox, energy metabolism and substance transport. IPF7817, IPF11105 and FDH11, the three putative Cap1p target genes functionally related to redox, were shown to be activated by oxidative stress in a Cap1p-dependent manner. Furthermore, rhodamine 6G efflux analyses demonstrated that Cap1p contributed to the energy-driven efflux. Taken together, these results reveal that Cap1p plays a significant role in redox status regulation, energy metabolism and substance transport under normal culture condition.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/fisiologia , Candida albicans/metabolismo , Proteínas Fúngicas/fisiologia , Estresse Oxidativo , Fatores de Transcrição de Zíper de Leucina Básica/genética , Transporte Biológico , Candida albicans/genética , Metabolismo Energético , Proteínas Fúngicas/genética , Deleção de Genes , Perfilação da Expressão Gênica , Regulação Fúngica da Expressão Gênica , Análise de Sequência com Séries de Oligonucleotídeos , Oxirredução , Elementos de Resposta , Reação em Cadeia da Polimerase Via Transcriptase Reversa
19.
Medchemcomm ; 8(5): 1093-1102, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30108820

RESUMO

Twenty-three monoketone derivatives of curcumin were synthesized to investigate the synergy with fluconazole against fluconazole-resistant Candida spp. The minimal inhibitory concentration (MIC80) and the fractional inhibitory concentration index (FICI) of the antifungal synergist fluconazole were measured against fluconazole-resistant C. albicans, C. tropicalis and C. krusei in vitro. Most of these compounds showed good synergistic activities against C. tropicalis. Among them, compound 9 exhibited significant synergistic activities against Candida spp. SARs were also discussed. In particular, a cell growth test exhibited that a combination of 1 µg ml-1 fluconazole and 64 µg ml-1 or 128 µg ml-1 compound 9 showed the most potent fungicidal effect against C. tropicalis. The synergistic effect may be associated with the changes of the intracellular ATP content and cell membrane permeability. Our results provided a basis for future evaluation and development of these compounds as leads for therapeutics for fluconazole-resistant candidiasis.

20.
Nat Prod Res ; 31(20): 2335-2340, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28322075

RESUMO

Two new phenolic glycoside, 2-methoxy-4-hydroxylphenyl-1-O-α-L-rhamnopyranosyl- (1″ â†’ 6')-ß-D-glucopyranoside. (1) and threo-3-methoxy-5-hydroxy-phenylpropanetriol-8-O-ß-D-glucopyranoside (2), were isolated from the stems of Zanthoxylum armatum. The compounds 1 and 2 showed weak scavenging activity in DPPH free radical assay with IC50 values of 323 and 114 mM, respectively.


Assuntos
Sequestradores de Radicais Livres/química , Glicosídeos/química , Fenóis/química , Zanthoxylum/química , Sequestradores de Radicais Livres/isolamento & purificação , Glicosídeos/isolamento & purificação , Estrutura Molecular , Fenóis/isolamento & purificação , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Caules de Planta/química
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