Acid-bile, antibiotic resistance and inhibitory properties of propionibacteria isolated from Turkish traditional home-made cheeses

In this study, a total of 29 Propionibacterium spp. were isolated from traditional home-made Turkish cheese samples. As a result of the identification, isolates were identified as Propionibacterium freudenreichii subsp. freudenreichii (15 strains), Propionibacterium jensenii (12), and Propionibacterium thoenii (2). All isolates and 5 reference strains were examined for their abilities to survive at pH 2.0, 3.0, 4.0, 5.0 and in the presence of 0.06, 0.15 and 0.30% bile salts, their influence on the growth of food-borne and spoilage bacteria, as well as their sensitivity against 11 selected antibiotics. Only seven propionibacteria strains survived in both the acidic and bile salt environments. Propionibacterium spp. strains strongly inhibited growth of the Escherichia coli ATCC 11229 and Shigella sonnei Mu:57 strains (91%). All propionibacteria strains were sensitive to a majority of the antibiotics used in the investigations. Overall, dairy propionibacteria showed high antibacterial activity, resistance to pH 4.0, 5.0, high resistance to bile salts and will provide an alternative source to Lactobacillus and Bifidobacterium as probiotic culture.     

Delineating the Specific Influence of Virus Isoelectric Point and Size on Virus Adsorption and Transport through Sandy Soils

Many of the factors controlling viral transport and survival within the subsurface are still poorly understood. In order to identify the precise influence of viral isoelectric point on viral adsorption onto aquifer sediment material, we employed five different spherical bacteriophages (MS2, PRD1, Qβ, X174, and PM2) having differing isoelectric points (pI 3.9, 4.2, 5.3, 6.6, and 7.3 respectively) in laboratory viral transport studies. We employed conventional batch flowthrough columns, as well as a novel continuously recirculating column, in these studies. In a 0.78-m batch flowthrough column, the smaller phages (MS2, X174, and Qβ), which had similar diameters, exhibited maximum effluent concentration/initial concentration values that correlated exactly with their isoelectric points. In the continuously recirculating column, viral adsorption was negatively correlated with the isoelectric points of the viruses. A model of virus migration in the soil columns was created by using a one-dimensional transport model in which kinetic sorption was used. The data suggest that the isoelectric point of a virus is the predetermining factor controlling viral adsorption within aquifers. The data also suggest that when virus particles are more than 60 nm in diameter, viral dimensions become the overriding factor.     

Chemical Composition and Biological Activity of Centaurea baseri: New Species from Turkey

The genus Centaurea L. is one of the largest and important genera of Asteraceae family. Centaurea species have been widely used as herbal remedies in folk medicine for their antidandruff, antidiarrheic, antirheumatic, anti‐inflammatory, choleretic, diuretic, digestive, stomachic, astringent, antipyretic, cytotoxic, and antibacterial properties. Centaurea baseri Kose & Alan is a recently described local endemic species in Turkey and this is the first study on the chemical composition and bioactivity of its hydrodistilled essential oil and the crude extract. According to chromatospectral analysis, hexadecanoic acid (42.3%), nonacosane (8.2%), and heptacosane (8.0%) were the main compounds of the essential oil, while 16 compounds were determined in the MeOH extract using LC/MS. Furthermore, antimicrobial, antioxidant, and cytotoxic effects of the essential oil and the extract were evaluated in comparison with the standard agents. The extract showed strong antifungal effect against Candida utilis at the concentration of 60 μg/ml (MIC) where the EO showed growth inhibition at the concentration of 47.00 μg/ml (MIC) against pathogen Bacillus cereus. Both the essential oil and the extract did not show any selective antioxidant properties. The extract showed remarkably selective cytotoxic properties against MCF‐7, PANC‐1, A549, and C6 glioma cells.     

PROGRESS STUDY: Progression of chronic kidney disease in children and heat shock proteins

Various molecular and cellular processes are involved in renal fibrosis, such as oxidative stress, inflammation, endothelial cell injury, and apoptosis. Heat shock proteins (HSPs) are implicated in the progression of chronic kidney disease (CKD). Our aim was to evaluate changes in urine and serum HSP levels over time and their relationships with the clinical parameters of CKD in children. In total, 117 children with CKD and 56 healthy children were examined. The CKD group was followed up prospectively for 24 months. Serum and urine HSP27, HSP40, HSP47, HSP60, HSP70, HSP72, and HSP90 levels and serum anti-HSP60 and anti-HSP70 levels were measured by ELISA at baseline, 12 months, and 24 months. The urine levels of all HSPs and the serum levels of HSP40, HSP47, HSP60, HSP70, anti-HSP60, and anti-HSP70 were higher at baseline in the CKD group than in the control group. Over the months, serum HSP47 and HSP60 levels steadily decreased, whereas HSP90 and anti-HSP60 levels steadily increased. Urine HSP levels were elevated in children with CKD; however, with the exception of HSP90, they decreased over time. In conclusion, our study demonstrates that CKD progression is a complicated process that involves HSPs, but they do not predict CKD progression. The protective role of HSPs against CKD may weaken over time, and HSP90 may have a detrimental effect on the disease course.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12192-021-01239-9.     

Immobilization of catalase via adsorption onto -histidine grafted functional pHEMA based membrane

Poly(2-hydroxyethylmethacrylate) (pHEMA) based flat sheet membrane was prepared by UV-initiated photopolymerization technique. The membrane was then grafted with -histidine. Catalase immobilization onto the membrane from aqueous solutions containing different amounts of catalase at different pH was investigated in a batch system. The maximum catalase immobilization capacity of the pHEMA–histidine membrane was 86 μg cm⁻². The activity yield was decreased with the increase of the enzyme loading. It was observed that there was a significant change between V_max value of the free catalase and V_max value of the adsorbed catalase on the pHEMA–histidine membrane. The K_m value of the immobilized enzyme was higher 1.5 times than that of the free enzyme. Optimum operational temperature was 5°C higher than that of the free enzyme and was significantly broader. It was observed that enzyme could be repeatedly adsorbed and desorbed without loss of adsorption capacity or enzyme activity.     

Serum free prostate-specific antigen and zinc levels in experimental acute pancreatitis

Serum free prostate-specific antigen (fPSA) is the most useful tumor marker for prostatic cancer screening. However, recently, fPSA has also been detected in sera from patients with pancreatic diseases. In addition, it has been shown that zinc (Zn) concentration might change in both serum and tissues in pancreatic disease. In the present study, we measured serum concentrations of fPSA and Zn as possible markers and prognostic factors in an experimental acute-pancreatitis model. Twenty-five female Wistar albino rats were divided into two groups: the control group (n=10) and the experimental group (n=15). Acute pancreatitis was induced by injection of ethyl alcohol into the common biliary duct. The animals were sacrificed 24 h later to detect the concentrations of serum fPSA and Zn. fPSA values were detected to be significantly higher in the experimental group p<0.001). There was also a significant decrease in the serum Zn level of the acute-pancreatitis group (p<0.001). In conclusion, these findings suggested that a combination of these parameters might represent a significant improvement on the diagnostic value of each of them separately and provide a powerful tool for differential diagnosis and prognosis in pancreatic diseases.     

Reconstruction of orbital floor fracture using solvent-preserved bone graft

The orbital floor is one of the most frequently damaged parts of the maxillofacial skeleton during facial trauma. Unfavorable aesthetic and functional outcomes are frequent when it is treated inadequately. The treatment consists of spanning the floor defect with a material that can provide structural support and restore the orbital volume. This material should also be biocompatible with the surrounding tissues and easily reshaped to fit the orbital floor. Although various autografts or synthetic materials have been used, there is still no consensus on the ideal reconstruction method of orbital floor defects. This study evaluated the applicability of solvent-preserved cadaveric cranial bone graft and its preliminary results in the reconstruction of the orbital floor fractures. Twenty-five orbital floor fractures of 21 patients who underwent surgical repair with cadaveric bone graft during a 2-year period were included in this study. Pure blowout fractures were determined in nine patients, whereas 12 patients had other accompanying maxillofacial fractures. Of the 21 patients, 14 had clinically evident diplopia (66.7 percent), 12 of them had enophthalmos (57.1 percent), and two of them had gaze restriction preoperatively. Reconstruction of the floor of the orbit was performed following either the subciliary or the transconjunctival approach. A cranial allograft was placed over the defect after sufficient exposure. The mean follow-up period was 9 months. Postoperative diplopia, enophthalmos, eye motility, cosmetic appearance, and complications were documented. None of the patients had any evidence of diplopia, limited eye movement, inflammatory reactions in soft tissues, infection, or graft extrusion in the postoperative period. Providing sufficient orbital volume, no graft resorption was detected in computed tomography scan controls. None of the implants required removal for any reason. Enophthalmos was seen in one patient, and temporary scleral show lasting up to 3 to 6 weeks was detected in another three patients. Satisfactory cosmetic results were obtained in all patients. This study showed that solvent-preserved bone, which is a nonsynthetic, human-originated, processed bioimplant, can be safely used in orbital floor repair and can be considered as another reliable treatment alternative.