Design, Synthesis and Antibacterial Evaluation of 1-[(1R,2S)-2-Fluorocyclopropyl]ciprofloxacin-1,2,4-triazole-5(4H)-thione Hybrids.

A new class of 1-[(1R,2S)-2-fluorocyclopropyl]ciprofloxacin (CPFX)-1,2,4-triazole-5(4H)-thione hybrids 6a - 6o was designed, synthesized and evaluated for their in vitro antibacterial activities against a panel of clinically important drug-sensitive and drug-resistant Gram-positive and Gram-negative pathogens. Our results revealed that all hybrids 6a - 6o had great potency against the tested strains, especially Gram-negative pathogens. The synthesized hybrids were more potent than the parent 1-[(1R,2S)-2-fluorocyclopropyl]CPFX (1) and comparable to CPFX and levofloxacin against the majority of the tested pathogens, worth to be further investigated.

Synthesis and In Vitro Antimycobacterial and Antibacterial Activity of 8-OMe Ciprofloxacin-Hydrozone/Azole Hybrids.

A series of novel 8-OMe ciprofloxacin (CPFX)-hydrazone/azole hybrids were designed, synthesized, and evaluated for their in vitro biological activities. Our results reveal that all of the hydrozone-containing hybrids (except for ) show potency against (MTB) HRv (minimum inhibitory concentration (MIC): <0.5 μM), which is better than the parent drug CPFX, and comparable to moxifloxacin and isoniazid, some of the tested Gram-positive strains (MIC: 0.

Characterization and Expression of Chicken Selenoprotein U.

Selenoprotein U (SelU) may regulate a myriad of biological processes through its redox function. In chicks, neither the nucleotide sequence nor the amino acid sequence is known. The main objectives of this study were to clone and characterize the chicken Selu gene and investigate Selu messenger RNA (mRNA) and protein expression in chicken tissues.

Spectroscopic investigation of the influence of calcium ion on the structures of casein micelles.

The effects of calcium ion on the structural properties of casein micelles in the course of heat treatment were synthetically examined by non-structure-invasive spectrometry. The hydrophobicity, reflected by extrinsic fluorescence (ANS fluorescence), was positively correlated with the concentration of the calcium ion, within the range of 0 to 12 mmol x L(-1). Meanwhile, the turbidity and stability of casein micelles also increased with the growth of calcium concentrations.

Bovine lactoferrin binds oleic acid to form an anti-tumor complex similar to HAMLET.

α-Lactalbumin (α-LA) can bind oleic acid (OA) to form HAMLET-like complexes, which exhibited highly selective anti-tumor activity in vitro and in vivo. Considering the structural similarity to α-LA, we conjectured that lactoferrin (LF) could also bind OA to obtain a complex with anti-tumor activity. In this study, LF-OA was prepared and its activity and structural changes were compared with α-LA-OA.

Synthesis, antimycobacterial and antibacterial activity of ciprofloxacin derivatives containing a N-substituted benzyl moiety.

We report herein the design and synthesis of a series of novel ciprofloxacin (CPFX) derivatives with remarkable improvement in lipophilicity by introducing a substituted benzyl moiety to the N atom on the C-7 piperazine ring of CPFX. Antimycobacterial and antibacterial activity of the newly synthesized compounds was evaluated. Results reveal that compound 4f has good in vitro activity against all of the tested Gram-positive strains including MRSA and MRSE (MICs: 0.

[Spectral properties of interaction between caffeic acid and milk protein and the change in antioxidant capacity].

The interaction between caffeic acid and milk protein (alpha-casein, beta-casein, kappa-casein, alpha-lactalbumin, beta-lactoglobulin) were studied in this work. The binding constant K(A), binding force, binding distance r(0) and transfer efficiency E were evaluated by UV-absorption and fluorescence spectroscopy. The antioxidant capacity of the combination was determined using both 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and ferric reducing antioxidant power (FRAP) assay.

In vitro antibacterial activity of chinfloxacin, a new fluoroquinolone antibiotic.

Background: Chinfloxacin is a novel synthetic fluoroquinolone with a structure similar to moxifloxacin. The in vitro activity of chinfloxacin was evaluated in the current study.

Method: Chinfloxacin was tested against a total of 1,739 clinical isolates representing 23 species using the agar dilution method.

[A comparison of different treatment conditions on the conformation changes of bovine lactoferrin].

In this study, the tertiary, secondary structures and disulfide bond changes of bovine lactoferrin (bLF) under 6 differents physico-chemical treatments were investigated by fluorescence, circular dichroism(CD) and UV-Vis absorption. A red shift from 333 to 354 nm in the fluorescence emission maximum (lambda(max)) was observed in the bLF treated by 6 mol x L(-1) GdnHCl, 8 mol x L(-1) Urea and 50 mmol x L(-1) DTT simultaneously, meanwhile a large number of exposed hydrophobic groups were detected. However, there was no marked shift in lambda(max) of bLF treated by heating (100 degrees C, 5 min), Ultrosonic(450 W, 5 s, 6 pulses) or beta-ME (1%), of which fluorescence intensity decreased significantly compared with the untreated bLF.

The secondary structure of heated whey protein and its hydrolysates antigenicity.

Fourier transform infrared spectroscopy (FTIR) and circular dichroism (CD) were used to investigate the conformational changes of heated whey protein (WP) and the corresponding changes in the hydrolysates immunoreactivity were determined by competitive enzyme-linked immunosorbent assay (ELISA). Results showed that the contents of alpha- helix and beta-sheet of WP did not decrease much under mild heating conditions and the antigenicity was relatively high; when the heating intensity increased (70 degrees for 25 min or 75 degrees C for 20 min), the content of alpha- helix and beta-sheet decreased to the minimum, so was the antigenicity; However, when the WP was heated at even higher temperature and for a longer time, the beta-sheet associated with protein aggregation begun to increase and the antigenicity increased correspondingly. It was concluded that the conformations of heated WP and the antigenicity of its hydrolysates are related and the optimum structure for decreasing the hydrolysates antigeniity is the least content of alpha-helix and beta-sheet.

In vivo antibacterial activity of chinfloxacin, a new fluoroquinolone antibiotic.

Objectives: To evaluate the in vivo antibacterial efficacy of chinfloxacin, a novel fluoroquinolone, in murine systemic and local infection models.

Methods: The efficacy of chinfloxacin in systemic infection was evaluated in a mouse peritonitis model using isolates of methicillin-susceptible Staphylococcus aureus (MSSA, n = 3), methicillin-resistant Staphylococcus aureus (MRSA; n = 1), penicillin-intermediate Streptococcus pneumoniae (PISP; n = 1), penicillin-resistant S. pneumoniae (PRSP; n = 2), vancomycin-susceptible Enterococcus faecalis (VSE; n = 1), vancomycin-resistant E.

[FTIR analysis of cosrelation between emulsifying properties and the secondary structure of the proteins in modified egg yolk powder ].

Spray drying is an important processing of producing modificatied yolk powder (MEYP). To investigate the correlation between the secondary structure and emulsifying property of MEYP made at different spray-drying-temperatures, Fourier transform infrared spectroscopy (FTIR) was applied in the present study. The result indicated that emulsifiability and the percentage of alpha-helix were both significantly increased firstly and then remarkably decreased with rising of spray-drying-temperature, and the emulsifying property of MEYP was relative to the percentage of alpha-helix.

Synthesis and in-vitro antimycobacterial activity of fluoroquinolone derivatives containing a coumarin moiety.

A series of gatifloxacin, ciprofloxacin, and 8-OCH(3) ciprofloxacin coumarin derivatives with remarkable improvement in lipophilicity as compared to the parent fluoroquinolones was designed, synthesized, and characterized by (1) H-NMR, MS, and HRMS. These derivatives were evaluated for their in-vitro activity against Mycobacterium smegmatis CMCC 93202 and MTB H37Rv ATCC 27294. All of the synthesized compounds were less active than the parent compounds against M.

FTIR analysis of protein secondary structure in cheddar cheese during ripening.

Proteolysis is one of the most important biochemical reactions during cheese ripening. Studies on the secondary structure of proteins during ripening would be helpful for characterizing protein changes for assessing cheese quality. Fourier transform infrared spectroscopy (FTIR), with self-deconvolution, second derivative analysis and band curve-fitting, was used to characterize the secondary structure of proteins in Cheddar cheese during ripening.

[Interaction of lactoferrin and its peptides with DPPC and DPPG liposomes studied by Raman spectroscopy].

Interaction of lactoferrin and its peptides LfcinB4-14 and LfampinB with dipalmitoylglycero-phosphocholine (DPPC) and dipalmitoylglycero-phosphoglycerol (DPPG) liposomes were studied by means of Raman spectroscopy. In our study, conformational changes in the phospholipid molecules were investigated by measuring the intensities of 2 847 and 2 882 cm(-1) Raman bands which are assigned to acyl chains' symmetric and asymmetric C-H stretching vibrations. The addition of lactoferrin and its peptides LfcinB4-14 and LfampinB caused a decrease in the 2 882 cm(-1) intensity of DPPG liposomes, thus the order parameter for the lateral interactions between chains S(lat) decreased from 0.

Synthesis and in vitro antibacterial activity of a series of novel gatifloxacin derivatives.

A series of novel gatifloxacin (GTFX) derivatives were designed, synthesized and characterized by (1)H NMR, (13)C NMR, MS and HRMS. These derivatives were evaluated for in vitro antibacterial activity against representative Gram-positive and Gram-negative strains. Our results reveal that most of the target compounds show good potency in inhibiting the growth of Staphylococcus aureus including MRSA and Staphylococcus epidermidis including MRSE.

Synthesis and in-vitro antibacterial activity of 7-(3-aminopyrrolo[3,4-c]pyrazol-5(2H,4H,6H)-yl)-6-fluoro-4-oxo-1,4-dihydroquinoline-3-carboxylic acid derivatives.

A series of novel 7-(3-aminopyrrolo[3,4-c]pyrazol-5(2H,4H,6H)-yl)-6-fluoro-4-oxo-1,4-dihydroquinoline-3-carboxylic acid derivatives was designed, synthesized and characterized by (1)H-NMR, MS and HRMS. These fluoroquinolones were evaluated for their in-vitro antibacterial activity against representative Gram-positive and Gram-negative strains. Generally, all of the target compounds display rather weak potency against the tested Gram-negative strains, but most of them exhibit good potency in inhibiting the growth of S.

Synthesis and in vitro antibacterial activity of 7-(3-alkoxyimino-4-amino-4-methylpiperidin-1-yl) fluoroquinolone derivatives.

A series of novel 7-(3-alkoxyimino-4-amino-4-methylpiperidin-1-yl)fluoroquinolone derivatives were designed, synthesized and evaluated for their in vitro antibacterial activity and cytotoxicity. All of the target compounds have potent antibacterial activity against the tested Gram-positive and Gram-negative strains, and exhibit good potency in inhibiting the growth of Staphylococcus aureus including MRSA, Staphylococcus epidermidis including MRSE and Streptococcus pneumoniae (MICs: 0.125-4 μg/mL).

Synthesis and in vitro antibacterial activity of 7-(3-amino-6,7-dihydro-2-methyl-2H-pyrazolo[4,3-c] pyridin-5(4H)-yl)fluoroquinolone derivatives.

A series of novel 7-(3-amino-6,7-dihydro-2-methyl-2H-pyrazolo[4,3-c]pyridin- 5(4H)-yl)fluoroquinolone derivatives were designed, synthesized and characterized by 1H-NMR, MS and HRMS. These fluoroquinolones were evaluated for their in vitro antibacterial activity against representative Gram-positive and Gram-negative strains. Results reveal that most of the target compounds exhibit good growth inhibitory potency against methicillin-resistant Staphylococcus epidermidis (MRSE) (MIC: 0.

Synthesis and in vitro antimycobacterial activity of 8-OCH(3) ciprofloxacin methylene and ethylene isatin derivatives.

A series of novel 8-OCH(3) ciprofloxacin methylene and ethylene isatin derivatives with remarkable improvement in lipophilicity were synthesized in this study. These derivatives were evaluated for their in vitro activity against some mycobacteria. All of the synthesized compounds were less active than the parent 8-OCH(3) ciprofloxacin against Mycobacteriumsmegmatis CMCC 93202, but most of the methylene isatin derivatives were more active than 8-OCH(3) ciprofloxacin, ciprofloxacin, isoniazid and rifampin against MTB H37Rv ATCC 27294.

Synthesis and in vitro antibacterial activity of 7-(4-alkoxyimino-3-methyl-3-methylaminopiperidin-1-yl)quinolones.

To explore new agents of quinolone derivatives with high antibacterial activity, 7-(4-alkoxyimino-3-methyl-3-methylaminopiperidin-1-yl)quinolones were designed and synthesized, and their activity against gram-positive and gram-negative strains was tested in vitro. Sixteen target compounds were obtained. Their structures were established by 1H NMR, HRMS and X-ray crystallographic analysis.

Synthesis and in vitro antibacterial activity of fluoroquinolone derivatives containing 3-(N'-alkoxycarbamimidoyl)-4-(alkoxyimino) pyrrolidines.

A series of novel 7-[3-(N'-alkoxycarbamimidoyl)-4-(alkoxyimino)pyrrolidin-1-yl] fluoroquinolone derivatives were designed, synthesized and characterized by (1)H NMR, MS and HRMS. These fluoroquinolones were screened for their in vitro antibacterial activity. Most of them exhibit good potency in inhibiting the growth of Staphylococcus aureus and Staphylococcus epidermidis (MIC: 0.

Synthesis and in vitro antimycobacterial activity of balofloxacin ethylene isatin derivatives.

A series of novel balofloxacin ethylene isatin derivatives with remarkable improvement in lipophilicity, as compared to the parent compound balofloxacin, were designed, synthesized and characterized by (1)H NMR, MS and HRMS. These derivatives were initially evaluated for their in vitro antimycobacterial activity against M. phlei CMCC 93201 and M.

Synthesis and in vitro antibacterial activity of 7-(3-alkoxyimino-4-methyl-4-methylaminopiperidin-1-yl)-fluoroquinolone derivatives.

A series of novel 7-(3-alkoxyimino-4-methyl-4-methylaminopiperidin-1-yl)fluoroquinolone derivatives were designed, synthesized, and characterized by 1H-NMR, MS, and HRMS. These fluoroquinolones were evaluated for their in-vitro antibacterial activity against representative Gram-positive and Gram-negative strains. Generally, all of the target compounds have considerable antibacterial activity against the tested forty strains, and exhibit exceptional potency in inhibiting the growth of methicillin-sensitive Staphylococcus aureus (MSSA) and methicillin-resistant S.

[A quantitative trabecular structural analysis using X-ray micro CT in ovariectomized rats].

The objective of the present paper was to evaluate the X-ray three-dimensional micro-computed tomography (X-microCT) method applied in assessing the trabecular structure in ovariectomized rats. Three-month-old female Sprague-Dawley rats (n = 30) were ovariectomized (OVX) or sham-operated (SHAM). OVX rats were treated with vehicle, or 17beta-estradiol (E2, positive control) for 3 months.