Design, synthesis, and in vitro evaluation of novel triazole analogues featuring isoxazole moieties as antifungal agents.

In order to develop novel antifungal agents, based on our previous work, a series of (2R,3R)-3-((3-substitutied-isoxazol-5-yl)methoxy)-2-(2,4-difluorophenyl)-1-(1H-1,2,4-triazol-1-yl) butan-2-ol (a1-a26) were designed and synthesized. All of the compounds exhibited good in vitro antifungal activities against eight human pathogenic fungi. Among them, compound a6 showed excellent inhibitory activity against Candida albicans and Candida parasilosis with MIC80 values of 0.0313 µg/mL. In addition, compounds a6, a9, a12, a13 and a14 exhibited moderate inhibitory activities against fluconazole-resistant isolates with MIC80 values ranging from 8 µg/mL to 16 µg/mL. Furthermore, compounds a6, a12 and a23 exhibited low inhibition profiles for CYP3A4. Clear SARs were analyzed, and the molecular docking experiment was carried out to further investigate the relationship between a6 and the target enzyme CYP51.

Design, synthesis, and structure-activity relationship studies of novel tetrazole antifungal agents with potent activity, broad antifungal spectrum and high selectivity.

In this letter, we report our efforts to design, synthesize and evaluate biological activities of a series of novel hybridized compounds containing 1-tetrazole and 4-pyridinyl-1,2,4-triazole-3-one. An analysis of structure-activity data indicates that the target compounds with bulky and hydrophobic side chains exhibited stronger activities against the Candida spp and Cryptococcus neoformans tested than those of fluconazole and racemic VT-1161. Furthermore, 13k and 13ad were active against Microsporum gypseum, which was resistant to racemic VT-1161. In addition, 13k, 13ac and 13ad, with good in vitro activities against all of pathogenic fungi tested except for Aspergillus fumigatus, had no inhibition of human CYP3A4, suggesting a low risk of drug-drug interactions.

Design, synthesis, and structure-activity relationship studies of novel thienopyrrolidone derivatives with strong antifungal activity against Aspergillus fumigates.

In order to further enhance the anti-Aspergillus efficacy of our previously discovered antifungal lead compounds (I), two series of novel azoles featuring thieno[2,3-c]pyrrolidone and thieno[3,2-c]pyrrolidone nuclei were designed and evaluated for their in vitro activity on the basis of the binding mode of albaconazole using molecular docking, along with SARs of antifungal triazoles. Most of target compounds exhibited excellent activity against Candida and Cryptococcus spp., with MIC values in the range of 0.0625 µg/ml to 0.0156 µg/ml. The thieno[3,2-c]pyrrolidone unit was more suited for improving activity against Aspergillus spp. The most potent compound, 18a, was selected for further development due to its significant in vitro activity against Aspergillus spp. (MIC = 0.25 µg/ml), as well as its high metabolic stability in human liver microsomes.

A comparison of Luminex xTAG® Gastrointestinal Pathogen Panel (xTAG GPP) and routine tests for the detection of enteropathogens circulating in Southern China.

To investigate whether Luminex xTAG® Gastrointestinal Pathogen Panel (xTAG GPP) is applicable for the diagnosis of diarrhea and surveillance of enteropathogens circulating in Southern China, 290 stool samples were tested for 15 kinds of enteropathogens using xTAG GPP and compared to the results from the routine tests, including culture; immunochromatography; real-time PCR; microscopy; and a third method, gene sequencing. One hundred fifty-nine samples were positive, yielding a total of 181 enteropathogens (69 bacteria and 112 viruses), with rotavirus being most prevalent (39.0%, 62/159). The overall sensitivity and specificity of xTAG GPP were 96.3% (93.3-98.2%) and 99.8% (99.6-99.9%), respectively, with a combination of the methods as the gold standard. The coinfection rates detected by the routine tests and xTAG GPP were 10.0% (25 double and 4 triple infections) and 12.1% (29 double, 4 triple and 2 quadruple infections), respectively. xTAG GPP is a powerful tool for the identification of multiple enteropathogens.

Novel triazolyl berberine derivatives prepared via CuAAC click chemistry: synthesis, anticancer activity and structure-activity relationships.

To search for novel anticancer agents, we designed and synthesized a series of new triazolyl berberine derivatives. The evaluation of all the synthesized compounds and their anticancer activities against a panel of four human cancer cell lines including MCF-7 (breast), MCF-7/ADR (breast), SW-1990 (pancreatic), SMMC-7721 (liver) and the noncancer cell line HUVEC (human umbilical vein endothelial cell). The results showed that most of the compounds displayed better anticancer activities against MCF-7 and SMMC-7721 compared with berberine. Among these derivatives, compounds 5p and 5a exhibited the most potent inhibitory activities against the SMMC-7721 and SW-1990 cell lines with IC50 values of 14.861 ± 2.4 µM and 16.798 ± 3.4 µM. Furthermore, compounds 5p, 5a and 5n exhibited much better selectivity toward the normal cell line HUVEC than berberine.

Novel Triazolyl berberine derivatives prepared via CuAAC click chemistry: Synthesis, Anticancer Activity and Structure-Activity Relationships.

To search for novel anticancer agents, we designed and synthesized a series of new triazolyl berberine derivatives. The evaluation of all the synthesized compounds and their anticancer activities against a panel of four human cancer cell lines including MCF-7 (breast), MCF-7/ADR (breast), SW-1990 (pancreatic), SMMC-7721 (liver) and the non-cancer cell line HUVEC (human umbilical vein endothelial cell). The results showed that most of the compounds displayed better anticancer activities against MCF-7 and SMMC-7721 compared with berberine. Among these derivatives, compounds 5p and 5a exhibited the most potent inhibitory activities against the SMMC-7721 and SW-1990 cell lines with IC50 values of 14.861 ± 2.4 µM and 16.798 ± 3.4 µM. Furthermore, compounds 5p, 5a and 5n exhibited much better selectivity toward the normal cell line HUVEC than berberine.

Design, synthesis, and anticancer activity of novel berberine derivatives prepared via CuAAC "click" chemistry as potential anticancer agents.

A series of novel derivatives of phenyl-substituted berberine triazolyls has been designed and synthesized via copper-catalyzed azide-alkyne cycloaddition click chemistry in an attempt to develop antitumor agents. All of the compounds were evaluated for anticancer activity against a panel of three human cancer cell lines, including MCF-7 (breast), SW-1990 (pancreatic), and SMMC-7721 (liver) and the noncancerous human umbilical vein endothelial cell (HUVEC) cell lines. The results indicated that most of the compounds displayed notable anticancer activities against the MCF-7 cells compared with berberine. Among these derivatives, compound 16 showed the most potent inhibitory activity against the SW-1990 and SMMC-7721 cell lines, with half-maximal inhibitory concentration (IC50) values of 8.54±1.97 µM and 11.87±1.83 µM, respectively. Compound 36 exhibited the most potent inhibitory activity against the MCF-7 cell line, with an IC50 value of 12.57±1.96 µM. Compound 16 and compound 36 exhibited low cytotoxicity in the HUVEC cell line, with IC50 values of 25.49±3.24 µM and 30.47±3.47 µM. Furthermore, compounds 14, 15, 16, 17, 18, 32, and 36 exhibited much better selectivity than berberine toward the normal cell line HUVEC.

Comparison of MALDI-TOF MS, gene sequencing and the Vitek 2 for identification of seventy-three clinical isolates of enteropathogens.

OBJECTIVE: This study was performed to evaluate the analytical and practical performance of the matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) compared to the sequencing method and the Vitek 2 system for identification of enteropathogens in the clinical microbiology laboratory. METHODS: Ten type strains and 73 clinical isolates of enteropathogens representing eight genera were analyzed by MALDI-TOF MS. All isolates were also characterized by gene sequencing allowing interpretation of the results from MALDI-TOF MS. In addition, MALDI-TOF MS was compared with the Vitek 2 system for the identification of ten isolates of Aeromonas and six of Salmonella. RESULTS: As previously known, identification between Shigella and Escherichia coli is not possible to distinguish. MALDI-TOF MS produced the correct identifications for all other type strains and clinical isolates to the genus level. Fifteen Campylobacter jejuni, six Campylobacter coli, three Plesiomonas shigelloides, three Yersinia enterocolitica, two Clostridium difficile, one Vibrio parahaemolyticus, one Vibrio fluvialis, and one Vibrio cholera were all correctly identified to the species level. Genus and species identifications of ten Aeromonas and six Salmonella isolates by MALDI-TOF MS were consistent with those by the Vitek 2, but with much less cost and about ten times faster. CONCLUSIONS: This study demonstrates that MALDI-TOF MS is a powerful tool for fast, accurate and low-cost identification of enteropathogens in the clinical microbiology laboratory.

Design, synthesis, and structure-activity relationship studies of novel fused heterocycles-linked triazoles with good activity and water solubility.

Triazoles with fused-heterocycle nuclei were designed and evaluated for their in vitro activity on the basis of the binding mode of albaconazole using molecular docking, along with SAR of antifungal triazoles. Tetrahydro-[1,2,4]triazolo[1,5-a]pyrazine and tetrahydro-thiazolo[5,4-c]pyridine nuclei were preferable to the other four fused-heterocycle nuclei investigated. Potent in vitro activity, broad spectrum and better water solubility were attained when triazoles containing nitrogen aromatic heterocycles were attached to these two nuclei. The most potent compounds 27aa and 45x, with low hERG inhibition and hepatocyte toxicity, both exhibited excellent activity against Candida, Cryptococcus, and Aspergillus spp., as well as selected fluconazole-resistant strains. A high water-soluble compound 58 (the disulfate salt of 45x) displayed unsatisfactory in vivo activity because of its poor PK profiles. Mice infected with C.alb. SC5314 and C.alb. 103 (fluconazole-resistant strain) and administered with 27aa displayed significantly improved survival rates. 27aa also showed favorable pharmacokinetic (PK) profiles.

Manganese source affects manganese transport and gene expression of divalent metal transporter 1 in the small intestine of broilers.

In the present study, two experiments were conducted to investigate the effect of Mn source on Mn transport and the expression of a Mn transporter, divalent metal transporter 1 (DMT1), in the small intestine of broilers. In Expt 1, in situ ligated duodenal loops from Mn-deficient chicks (29-d-old) were perfused with solutions containing 0-8.74 mmol Mn/l from either MnSO4, or one of two organic chelates of Mn and amino acids with moderate (OM) or strong (OS) chelation strength (Q(f)) up to 30 min. In Expt 2, Mn-deficient intact broilers (14-d-old) were fed a control diet (12.45 mg Mn/kg) or the control diet supplemented with 100 mg Mn/kg as one of all Mn sources for 14 d. The uptake kinetics of Mn from different Mn sources in the ligated duodenal loops followed a saturable process as determined by regression analysis of concentration-dependent uptake rates. The maximum transport rate (Jmax) and K(m) values, and DMT1 mRNA levels in the ligated duodenal loops were higher (P < 0.01) for OM and OS than for MnSO4. DMT1 mRNA levels were much higher (P < 0.01) in the duodenum than in the jejunum and ileum. Both DMT1 mRNA levels in the duodenum and plasma Mn contents from the hepatic portal vein of intact chicks on day 14 post-feeding increased (P < 0.05) in the following order: control < MnSO4 < OM < OS. These results indicated that organic Mn sources with stronger Q(f) showed higher Mn transport and absorption, and DMT1 might be involved in the regulation of organic Mn transport in the proximal small intestine of broilers.

Preparation and characterization of medium-chain fatty acid liposomes by lyophilization.

In this study, medium-chain fatty acid (MCFA) liposomes were prepared by the film ultrasonic dispersion, modified ethanol injection, and reverse-phase evaporate methods. The results indicated that the liposomes prepared by the thin-film ultrasonic dispersion method had a high entrapment efficiency of 82.7% and a good distribution in size diameters. The MCFA liposomes were freeze-dried and the optimal preparation conditions of freeze-drying were as follows: The cryoprotectants were mannitol and sucrose (1:1 w/w), the hydrated medium was distilled water, and the freeze-drying time was 48 hours. Under these conditions, the freeze-dried MCFA liposomes had a perfect appearance, a small particle size, and high encapsulation efficiency. The mean diameters were 251.1 and 265.3 nm, and the encapsulation efficiencies were 80.5 and 79.2% for freshly prepared and reconstituted liposomes, respectively.