Synthesis of eperezolid-like molecules and evaluation of their antimicrobial activities

3-Fluoro-4-(4-phenylpiperazin-l-yl)aniline (II) prepared from 3,4-difluoro nitrobenzene was converted to the corresponding Schiff bases (III) and (IV) by treatment with 4-methoxybenzaldehyde and indol-3-carbaldehyde, respectively. Treatment of amine (II) with 4-fluorophenyl isothiocyanate afforded the corresponding thiourea derivative (V). Compound (V) was converted to thiazolidinone and thiazoline derivatives (VI) and (VII) by cyclocondensation with ethylbromoacetate or 4-chlorophenacylbromide, respectively. The synthesis of carbothioamide derivative (X) was performed starting from compound (II) by three steps. Treatment of compound (X) with sodium hydroxide, sulfuric acid, or chlorophenacyl bromide generated the corresponding 1,2,4-triazole (XI), 1,3,4-thiadiazole (XII), and 1,3-thiazolidinone (XIII) derivatives, respectively. The structural assignments of new compounds were based on their elemental analysis and spectral (IR, ¹H-NMR, ¹³C-NMR, and LC-MS) data. In the antimicrobial activity study all the compounds revealed high anti-Mycobacterium smegmatis activity.     

Synthesis and anti-Candida activity of novel 2-hydrazino-1,3-thiazole derivatives

Eighteen new hydrazino-1,3-thiazole derivatives were evaluated against 8 strains of multi-resistant Candida spp. Introduction of an indolyl moiety linked to the hydrazone function enhanced the in vitro anti-Candida activity, with an activity spectrum towards Candida albicans strains. Introduction of a (S)-2-aminoethyl chain on the thiazole nucleus largely enhanced the in vitro antifungal activity, with a selectivity oriented towards non-C. albicans species.     

Blood banking in living droplets

Blood banking has a broad public health impact influencing millions of lives daily. It could potentially benefit from emerging biopreservation technologies. However, although vitrification has shown advantages over traditional cryopreservation techniques, it has not been incorporated into transfusion medicine mainly due to throughput challenges. Here, we present a scalable method that can vitrify red blood cells in microdroplets. This approach enables the vitrification of large volumes of blood in a short amount of time, and makes it a viable and scalable biotechnology tool for blood cryopreservation.     

Penetration of cutting tool into cortical bone: Experimental and numerical investigation of anisotropic mechanical behaviour

An anisotropic mechanical behaviour of cortical bone and its intrinsic hierarchical microstructure act as protective mechanisms to prevent catastrophic failure due to natural loading conditions; however, they increase the extent of complexity of a penetration process in the case of orthopaedic surgery. Experimental results available in literature provide only limited information about processes in the vicinity of a tool–bone interaction zone. Also, available numerical models the bone-cutting process do not account for material anisotropy or the effect of damage mechanisms. In this study, both experimental and numerical studies were conducted to address these issues and to elucidate the effect of anisotropic mechanical behaviour of cortical bone tissue on penetration of a sharp cutting tool. First, a set of tool-penetration experiments was performed in directions parallel and perpendicular to bone axis. Also, these experiments included bone samples cut from four different cortices to evaluate the effect of spatial variability and material anisotropy on the penetration processes. Distinct deformation and damage mechanisms linked to different microstructure orientations were captured using a micro-lens high-speed camera. Then, a novel hybrid FE model employing a smoothed-particle-hydrodynamic domain embedded into a continuum FE one was developed based on the experimental configuration to characterise the anisotropic deformation and damage behaviour of cortical bone under a penetration process. The results of our study revealed a clear anisotropic material behaviour of the studied cortical bone tissue and the influence of the underlying microstructure. The proposed FE model reflected adequately the experimental results and demonstrated the need for the use of the anisotropic and damage material model to analyse cutting of the cortical-bone tissue.     

Genetic structure and diversity analysis revealed by AFLP on different Echinochloa spp. from northwest Turkey

Rice is one of the most economically important cereal crops in the world. The genus Echinochloa is the most competitive and difficult to control weeds in the rice fields. Improving the knowledge on the genetic diversity and structure of Echinochloa spp. can supply crucial information for designing effective management strategies for weed control in rice breeding. In the study, 28 Echinochloa spp. genotypes were subjected to the analysis of genetic diversity using four amplified fragment length polymorphism selective primer combinations. The number of polymorphic fragments per primer combination detected ranged from 28 to 50 bands with an average of 41.5 bands. Average polymorphic information content (PIC) was 0.26 in overall primer combinations. E_ACA-M_CAG primer combination showed the highest PIC (0.52) which can be a good candidate primer combination to verify genetic diversity in Echinochloa spp. The unweighted pair-group method of the arithmetic average and principal coordinate analysis showed a clear distinction among the genotypes and the genotypes divided into three clusters in the dendrogram results. A model-based structure analysis revealed the presence of two populations. The accessions were clearly assigned to a single population in which >70 % of their inferred ancestry was derived from one of the model-based populations. However, three genotypes (10.7 %) in the sample were categorized as having admixed ancestry. The study showed that genetic variation and population structure are determined among genotypes collected from different locations. High level of genetic variation in both intra and inter species was detected.     

Enhanced submerged Aspergillus ficuum phytase production by implementation of fed-batch fermentation

Phytase is an important feed and food additive, which is both used in animal and human diets. Phytase has been used to increase the absorption of several divalent ions, amino acids, and proteins in the bodies and to decrease the excessive phosphorus release in the manure to prevent negative effects on the environment. To date, microbial phytase has been mostly produced in solid-state fermentations with insignificant production volumes. There are only a few studies in the literature that phytase productions were performed in submerged bench-top reactor scale. In our previous studies, growth parameters (temperature, pH, and aeration) and important fermentation medium ingredients (glucose, Na-phytate, and CaSO₄) were optimized. This study was undertaken for further enhancement of phytase production with Aspergillus ficuum in bench-top bioreactors by conducting fed-batch fermentations. The results showed that addition of 60 g of glucose and 10 g of Na-phytate at 96 h of fermentation increased phytase activity to 3.84 and 4.82 U/ml, respectively. Therefore, the maximum phytase activity was further enhanced with addition of glucose and Na-phytate by 11 and 40 %, respectively, as compared to batch phytase fermentations. It was also reported that phytase activity increased higher in early log stage additions than late log stage additions because of higher microbial activity. In addition, the phytase activity in fed-batch fermentation did not drop significantly as compared to the batch fermentation. Overall, this study shows that fungal phytase can be successfully produced in submerged fed-batch fermentations.     

A Rare Duplication on Chromosome 16p11.2 Is Identified in Patients with Psychosis in Alzheimer's Disease

Epidemiological and genetic studies suggest that schizophrenia and autism may share genetic links. Besides common single nucleotide polymorphisms, recent data suggest that some rare copy number variants (CNVs) are risk factors for both disorders. Because we have previously found that schizophrenia and psychosis in Alzheimer''s disease (AD+P) share some genetic risk, we investigated whether CNVs reported in schizophrenia and autism are also linked to AD+P. We searched for CNVs associated with AD+P in 7 recurrent CNV regions that have been previously identified across autism and schizophrenia, using the Illumina HumanOmni1-Quad BeadChip. A chromosome 16p11.2 duplication CNV (chr16: 29,554,843-30,105,652) was identified in 2 of 440 AD+P subjects, but not in 136 AD subjects without psychosis, or in 593 AD subjects with intermediate psychosis status, or in 855 non-AD individuals. The frequency of this duplication CNV in AD+P (0.46%) was similar to that reported previously in schizophrenia (0.46%). This duplication CNV was further validated using the NanoString nCounter CNV Custom CodeSets. The 16p11.2 duplication has been associated with developmental delay, intellectual disability, behavioral problems, autism, schizophrenia (SCZ), and bipolar disorder. These two AD+P patients had no personal of, nor any identified family history of, SCZ, bipolar disorder and autism. To the best of our knowledge, our case report is the first suggestion that 16p11.2 duplication is also linked to AD+P. Although rare, this CNV may have an important role in the development of psychosis.     

Short-term hyperglycemia increases endothelial glycocalyx permeability and acutely decreases lineal density of capillaries with flowing red blood cells.

Hyperglycemia is becoming recognized as an important risk factor for microvascular dysfunction. We hypothesized that short-term hyperglycemia, either on the scale of hours or weeks, alters the barrier function and the volume of the endothelial glycocalyx and decreases functional capillary density and deformability of the red blood cells (RBCs). All experiments were performed in anesthetized, mechanically ventilated, C57BL/6 mice that were either normoglycemic, acutely hyperglycemic (25 mM) for 60 min due to infusion of glucose, or hyperglycemic (25 mM) for 2-4 wk (db/db mice). The glycocalyx was probed using 40-kDa Texas red dextran, which is known to permeate the glycocalyx, and 70-kDa FITC dextran, which has impaired access to the glycocalyx in healthy animals. Clearance of the dye from the blood was measured. An orthogonal polarization spectral imaging technique was used to visualize the number of capillaries with flowing RBCs of the dorsal flexor muscle. The data indicate that short-term hyperglycemia causes a rapid decrease of the ability of the glycocalyx to exclude 70-kDa dextran. No change in the vascular permeation of 40-kDa dextran was observed. Glycocalyx volume was not affected by short-term hyperglycemia. In addition, 1 h of hyperglycemia resulted in a 38% decrease of the lineal density of capillaries with flowing RBCs. This decreased lineal density was not observed in the 2- to 4-wk hyperglycemia model. Short-term hyperglycemia was without any effect on the deformablity of the RBCs. The data indicate that the described increased vascular permeability with hyperglycemia can be ascribed to an increased permeability of the glycocalyx, identifying the glycocalyx as a potential early target of hyperglycemia.     

A very simple high‐performance liquid chromatographic method with fluorescence detection for the determination of gemifloxacin in human breast milk

A high‐performance liquid chromatographic method with fluorescence detection was developed and validated for the determination of gemifloxacin in human breast milk. The proposed method allows the determination of gemifloxacin in breast milk samples without complex sample preparation. The samples were mixed with a mobile phase and filtered with a 0.45 µm polytetrafluoroethylene filter before analysis. Chromatographic separation was carried out on a C18 column (150 × 4.6 mm, 5 µm I.D.) using methanol:50 mM ortho‐phosphoric acid solution (40:60) as the mobile phase with a 1.0 mL/min flow rate. Quantitation was performed using fluorescence detection with an excitation wavelength at 272 nm and an emission wavelength at 395 nm. The linear range was found to be 0.1–2.5 µg/mL. The method was applied successfully for the determination of gemifloxacin in breast milk obtained from a breastfeeding mother after oral administration of a single tablet that included 320 mg gemifloxacin per gemifloxacin tablet. Copyright © 2015 John Wiley & Sons, Ltd.