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1.
World J Gastrointest Oncol ; 16(4): 1256-1267, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38660647

ABSTRACT

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.

2.
Hepatol Int ; 2024 Apr 09.
Article in English | MEDLINE | ID: mdl-38594474

ABSTRACT

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.

3.
Article in English | MEDLINE | ID: mdl-38429161

ABSTRACT

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.

4.
World J Gastrointest Oncol ; 15(6): 1051-1061, 2023 Jun 15.
Article in English | MEDLINE | ID: mdl-37389113

ABSTRACT

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.

5.
Digit Health ; 9: 20552076231179007, 2023.
Article in English | MEDLINE | ID: mdl-37312938

ABSTRACT

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.

6.
J Clin Transl Hepatol ; 9(5): 626-634, 2021 Oct 28.
Article in English | MEDLINE | ID: mdl-34722177

ABSTRACT

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.

7.
Front Chem ; 8: 581, 2020.
Article in English | MEDLINE | ID: mdl-32850623

ABSTRACT

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.

8.
Plant Biotechnol J ; 16(12): 2088-2101, 2018 12.
Article in English | MEDLINE | ID: mdl-29734518

ABSTRACT

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.


Subject(s)
Gene Editing/methods , Genes, Plant/genetics , Triticum/genetics , Zinc Fingers/genetics , DNA Repair/genetics , Genome, Plant/genetics , Polyploidy
9.
Nat Prod Res ; 31(20): 2335-2340, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28322075

ABSTRACT

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.


Subject(s)
Free Radical Scavengers/chemistry , Glycosides/chemistry , Phenols/chemistry , Zanthoxylum/chemistry , Free Radical Scavengers/isolation & purification , Glycosides/isolation & purification , Molecular Structure , Phenols/isolation & purification , Phytochemicals/chemistry , Phytochemicals/isolation & purification , Plant Stems/chemistry
10.
Medchemcomm ; 8(5): 1093-1102, 2017 May 01.
Article in English | MEDLINE | ID: mdl-30108820

ABSTRACT

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.

11.
Ying Yong Sheng Tai Xue Bao ; 26(8): 2455-65, 2015 Aug.
Article in Chinese | MEDLINE | ID: mdl-26685610

ABSTRACT

Dynamic evaluation of sustainable development is one of the key fundamental parts of the success of Sino-Singapore Tianjin Eco-city, which is the first eco-city in China constructed by international cooperation. Based on the analysis of nature and economy, function and structure, planning control indices and so on, we constructed a sustainable development evaluation index system and a system dynamics model of Sino-Singapore Tianjin Eco-city to explore dynamic trends of its population, material and currency by comprehensive utilization of emergy analysis and system dynamics method. Five scenarios were set up and simulated, including inertial scenario, scientific and technological scenario, economic scenario, environmental scenario and harmonious development scenario. Then, the sustainability of the 5 scenarios was evaluated and compared. The results showed that in the economy and environment sustainable development scenario, there was a steady growth trend of GDP, accumulation of both emergy and currency, and relatively lower values in emergy waste ratio, emergy ratio of waste, and emergy loading ratio. Although both sustainable evaluation indices, such as ESI and UEI, were relatively low, the economy and environment sustainable development scenario was still the best development scenario which was more active than others.


Subject(s)
Cities , Conservation of Natural Resources/economics , Ecosystem , China , Economic Development , Models, Theoretical , Singapore
12.
Fungal Genet Biol ; 80: 31-42, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25937438

ABSTRACT

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.


Subject(s)
Candida albicans/genetics , Fungal Proteins/genetics , Fungal Proteins/metabolism , Candida albicans/physiology , Fluconazole/pharmacology , Fungi/genetics , Fungi/physiology , Gene Expression Regulation, Fungal/drug effects , Mutation , Osmotic Pressure , Phenotype , RNA, Messenger/metabolism , Transcriptome/drug effects
13.
Nanoscale ; 6(17): 9939-43, 2014 Sep 07.
Article in English | MEDLINE | ID: mdl-25054637

ABSTRACT

We synthesize Au@Ag core/shell nanoparticles (NPs) using a Au NP assisted Tollens reaction. The as-synthesized NPs are used for the colorimetric cyanide sensing with a detection limit of 0.4 µM. The bimetallic NPs are immobilized into agarose gels as portable "test strips".

14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(4): 990-3, 2014 Apr.
Article in Chinese | MEDLINE | ID: mdl-25007615

ABSTRACT

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.


Subject(s)
Antihypertensive Agents/analysis , Chromatography, Thin Layer , Drug Contamination , Drugs, Chinese Herbal/analysis , Limit of Detection , Sensitivity and Specificity , Spectrum Analysis, Raman
15.
Mol Divers ; 17(3): 515-24, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23703159

ABSTRACT

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.


Subject(s)
Alzheimer Disease/drug therapy , Amyloid beta-Peptides/drug effects , Caffeic Acids/pharmacology , Lactates/pharmacology , Plaque, Amyloid/drug therapy , Serum Amyloid A Protein/drug effects , Animals , Caenorhabditis elegans/drug effects , Cell Line, Tumor , Circular Dichroism , Copper/chemistry , Drug Evaluation, Preclinical , Humans , Iron/chemistry , Iron Chelating Agents , Molecular Dynamics Simulation , Oxidative Stress/drug effects , Plant Extracts/pharmacology , Reactive Oxygen Species/antagonists & inhibitors , Salvia miltiorrhiza , Serum Amyloid A Protein/metabolism , Zinc/chemistry
16.
Biol Pharm Bull ; 34(5): 624-31, 2011.
Article in English | MEDLINE | ID: mdl-21532148

ABSTRACT

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.


Subject(s)
Candida albicans/genetics , Adaptation, Physiological/genetics , Base Sequence , Candida albicans/isolation & purification , Candida albicans/physiology , Chromosomes, Fungal , Comparative Genomic Hybridization , DNA Primers , Gene Dosage , Genes, Fungal , Open Reading Frames , Polymerase Chain Reaction , Retroelements
17.
J Microbiol Biotechnol ; 19(8): 803-9, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19734718

ABSTRACT

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.


Subject(s)
Antioxidants/administration & dosage , Apoptosis/drug effects , Candida albicans/drug effects , Flavanones/administration & dosage , Basic-Leucine Zipper Transcription Factors , Candida albicans/physiology , Candida albicans/ultrastructure , Candidiasis/drug therapy , Candidiasis/metabolism , Cell Cycle Proteins/genetics , Cell Cycle Proteins/metabolism , Fungal Proteins/genetics , Fungal Proteins/metabolism , Gene Expression Regulation, Fungal , Genes, Fungal , Humans , Membrane Potential, Mitochondrial/drug effects , Microscopy, Electron, Transmission , RNA, Fungal/biosynthesis , RNA, Fungal/genetics , Reactive Oxygen Species/metabolism , Up-Regulation
18.
Clin Exp Pharmacol Physiol ; 36(10): e40-6, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19413603

ABSTRACT

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.


Subject(s)
Antifungal Agents/therapeutic use , Ascorbic Acid/pharmacology , Candidiasis/drug therapy , Fluconazole/therapeutic use , Animals , Antifungal Agents/pharmacology , Antioxidants/pharmacology , Candida albicans/drug effects , Candidiasis/mortality , Disease Models, Animal , Drug Antagonism , Drug Evaluation, Preclinical , Drug Resistance, Fungal/drug effects , Fluconazole/pharmacology , Mice , Microbial Sensitivity Tests
19.
Article in Chinese | MEDLINE | ID: mdl-21158052

ABSTRACT

AIM: To observe the role of nitric oxide in dorsal root ganglion (DRG) neurons and its related ionic mechanisms, and explore the function of NO in pain transmission process. METHODS: In freshly isolated rat DRG samples, using intracellular recording technique, we perfused sodium nitroprusside (NO donor) to observe the role of NO in DRG neurons. RESULTS: In 77.45% of the bath cells, application of sodium nitroprusside (10 -100 mmol/L) induced concentration-dependent membrane hyperpolarization (79/102), and remaining neurons had no response. The membrane conductance increased from control value of (21.06 +/- 1.94) nS to (23.08 +/- 0.92) nS during sodium nitroprusside induced hyperpolarization. L-NAME (1 mmol/L), CdCl2 (0.1 mmol/L) and non-sodium BSS failed to change the amplitude of sodium nitroprusside induced hyperpolarization. When BSS containing 10 mmol/L TEA was used, sodium nitroprusside induced hyperpolarization was obviously inhibited. CONCLUSION: Sodium nitroprusside could cause concentration-dependent hyperpolarization in DRG neurons by activating K+ channels.


Subject(s)
Ganglia, Spinal/physiology , Membrane Potentials/physiology , Nitric Oxide/pharmacology , Pain/physiopathology , Animals , Female , Male , Neurons/physiology , Nitroprusside/pharmacology , Rats , Rats, Sprague-Dawley
20.
Biol Pharm Bull ; 31(12): 2234-6, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19043205

ABSTRACT

In vitro interaction of fluconazole and baicalein (BE) was investigated against 30 fluconazole-resistant clinical isolates of Candida albicans. Synergistic activities were determined using the checkerboard microdilution assay based on the fractional inhibitory concentration indices. Organisms were also tested against the 2 drugs singly and in combination using time-kill methods. Both fluconazole and BE showed weak antifungal activity when tested alone. However, the combination of fluconazole and BE showed strong antifungal activity against most of the fluconazole-resistant isolates tested. The findings of time-kill curves confirmed the interaction. Yeast cells grown in the presence of BE exhibited a reduced extrusion of Rhodamine 6G, which indicates the inhibition of efflux pumps by BE. This novel synergism of fluconazole and BE that can overcome drug-resistance in yeast may prove useful in combined treatment of fungal infections.


Subject(s)
Antifungal Agents/pharmacology , Candida albicans/drug effects , Drug Resistance, Fungal/drug effects , Flavanones/pharmacology , Fluconazole/pharmacology , Candidiasis/microbiology , Fluorescent Dyes , Glucose/pharmacology , Kinetics , Microbial Sensitivity Tests , Rhodamines
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