Point-of-care assays for tuberculosis: Role of nanotechnology/microfluidics

Tuberculosis (TB) remains one of the most devastating infectious diseases and its eradication is still unattainable given the limitations of current technologies for diagnosis, treatment and prevention. The World Health Organization's goal to eliminate TB globally by 2050 remains an ongoing challenge as delayed diagnosis and misdiagnosis of TB continue to fuel the worldwide epidemic. Despite considerable improvements in diagnostics for the last few decades, a simple and effective point-of-care TB diagnostic test is yet not available. Here, we review the current assays used for TB diagnosis, and highlight the recent advances in nanotechnology and microfluidics that potentially enable new approaches for TB diagnosis in resource-constrained settings.     

Altitudinal variation in the morphometric characteristics of Aedes vexans Meigen from northeastern Turkey

Body size is one of the most significant features of organisms and is correlated with a large number of ecological and physiological variables. Similar to size, biological shape is one of the most conspicuous aspects of an organism's phenotype and provides a link between the genotype and the environment. Body size may change with altitude and also habitat differences associated with altitude may affect the biological shape and some morphological characteristics. Four populations of Aedes vexans Meigen occurring in different ecological subregions at altitudes between 808–1,620 m in the Aras Valley from northeastern Turkey were compared using traditional and geometric morphometrics. When the wing shape differences of populations were analyzed by UPGM, the cluster analyses recognized two main groups of populations. Gödekli (808 m) comprised the first group while Zülfikar (848 m), Sürmeli (944 m), and Cilehane (1,620 m) populations comprised the second group. In the second group, Zülfikar and Cilehane populations showed a similar grouping pattern while Sürmeli appeared as a different group. Centroid sizes were used as measures of overall wing size differences among different regions. Aedes vexans from the Sürmeli region had relatively larger wings.     

Evaluating the addition of activated carbon to heat-treated mushroom casing for grain-based and compost-based substrates

Two substrates, a non-composted grain spawn substrate and a traditional composted substrate, each covered with peat-based casing that contained varying amounts of activated carbon (AC) and each receiving different heat-treatment durations, were tested for Agaricus bisporus mushroom production. The amounts of AC were 0, 5, 10, 15, and 20% v/v, and the heat treatments were 0, 60, and 180 min at 121 °C and 103.4 kPa. Overall, the addition of AC up to 10–15% of casing for a grain spawn substrate increased mushroom yield. However, the addition of AC to the casing for compost substrates had no significant effect on yield, whereas heat-treating the casing increased yield. The onset of fruiting was retarded in grain spawn treatments not receiving AC with heat-treatment durations of 60 and 180 min, whereas this effect was not as apparent for the compost substrates. On average, mushroom yield was greater for the grain spawn substrate (366 g) than for compost substrate (287 g). For grain spawn substrate, the results show that the addition of AC ranging from 5% to 10% was adequate for maximum mushroom production.     

Biotransformation of (-)-(R)-α-Phellandrene: Antimicrobial Activity of Its Major Metabolite

Terpene derivatives converted by microbial biotransformation constitute an important resource for natural pharmaceutical, fragrance, and aroma substances. In the present study, the monoterpene α-phellandrene was biotransformed by 16 different strains of microorganisms (bacteria, fungi, and yeasts). The transformation metabolites were initially screened by TLC and GC/MS, and then further characterized by NMR spectroscopic techniques. Among the six metabolites characterized, 6-hydroxypiperitone, α-phellandrene epoxide, cis-p-menth-2-en-1-ol, and carvotanacetone, which originated from (-)-(R)-α-phellandrene, are reported for the first time in this study. Additionally, the substrate and the metabolite 5-p-menthene-1,2-diol were subjected to in vitro antibacterial and anticandidal tests. The metabolite showed moderate-to-good inhibitory activities (MICs=0.125 to >4?mg/ml) against various bacteria and especially against Candida species in comparison with its substrate (-)-(R)-α-phellandrene and standard antimicrobial agents.     

Ingredient selection for plastic composite supports for L-(+)-lactic acid biofilm fermentation by Lactobacillus casei subsp. rhamnosus.

Plastic composite supports containing 50% agricultural products (oat hulls, soybean hulls, yeast extract, soybean flour, dried bovine erythrocytes, bovine albumin, and/or mineral salts) and 50% (wt/wt) polypropylene were produced by high-temperature twin-screw extrusion. The research employed two half sets of a five-factorial fractional design (2(5 - 1)) to evaluate the effects of different agricultural components on the properties of the plastic composite supports and to select the best plastic composite support formulation for lactic acid fermentation. The biofilm population was affected by the contact angle and relative hydrophobicity of the supports (r = 0.79 to 0.82). Lactic acid was produced by the suspended cells (r = 0.96) and the biofilm on the plastic composite support discs (r = 0.85). Incorporation of yeast extract into plastic composite supports enhanced growth of free and attached cells in minimal medium (P < 0.0001). The presence of soybean hulls, yeast extract, or mineral salts in plastic composite supports produced less hydrophobic supports (P < 0.0001) and enhanced cell attachment (P < 0.03). Under all conditions, suspended-cell and polypropylene disc controls gave negligible lactic acid production and cell density. Plastic composite supports containing soybean hulls, yeast extract, soybean flour, bovine albumin, and mineral salts gave the highest biofilm population (2.3 x 10(9) CFU/g of support), cell density (absorbance of 1.8 at 620 nm), and lactic acid concentration (7.6 g/liter) in minimal medium.     

Body fat distribution has no effect on serum visfatin levels in healthy female subjects

Obesity is the presence of either abnormal absolute amount or relative proportion of body fat. Contrary to gluteal obesity, visceral obesity is associated with different metabolic alterations including insulin resistance (IR). A relatively new adipocytokine visfatin is shown to be expressed predominantly in visceral fat and exhibit insulin-mimicking effects in rodents. It is still unclear whether serum visfatin levels are associated with increased total or visceral fat mass in humans. The aim of our study was to investigate the relation between visfatin and obesity parameters namely body mass index (BMI) and waist circumference (WaC) and IR in healthy female subjects. Eighty one female subjects ?20 years of age, having no diagnosis of glucose intolerance or diabetes, hypertension and dyslipidemia were chosen. The patients were divided into four groups according to their BMI and WaC values. Serum visfatin and HOMA-IR levels did not differ among groups. No correlation was detected between serum visfatin levels and obesity and metabolic parameters. In conclusion, we demonstrated that body fat distribution did not affect serum visfatin levels in healthy female subjects. Further studies are needed to clarify the exact factors influencing and determining serum visfatin levels and its clinical reflections.     

Production of human lysozyme in biofilm reactor and optimization of growth parameters of Kluyveromyces lactis K7

Lysozyme (1,4-β-N-acetylmuramidase) is a lytic enzyme, which degrades the bacterial cell wall. Lysozyme has been of interest in medicine, cosmetics, and food industries because of its anti-bactericidal effect. Kluyveromyces lactis K7 is a genetically modified organism that expresses human lysozyme. There is a need to improve the human lysozyme production by K. lactis K7 to make the human lysozyme more affordable. Biofilm reactor provides high biomass by including a solid support, which microorganisms grow around and within. Therefore, the aim of this study was to produce the human lysozyme in biofilm reactor and optimize the growth conditions of K. lactis K7 for the human lysozyme production in biofilm reactor with plastic composite support (PCS). The PCS, which includes polypropylene, soybean hull, soybean flour, bovine albumin, and salts, was selected based on biofilm formation on PCS (CFU/g), human lysozyme production (U/ml), and absorption of lysozyme inside the support. To find the optimum combination of growth parameters, a three-factor Box–Behnken design of response surface method was used. The results suggested that the optimum conditions for biomass and lysozyme productions were different (27 °C, pH 6, 1.33 vvm for biomass production; 25 °C, pH 4, no aeration for lysozyme production). Then, different pH and aeration shift strategies were tested to increase the biomass at the first step and then secrete the lysozyme after the shift. As a result, the lysozyme production amount (141 U/ml) at 25 °C without pH and aeration control was significantly higher than the lysozyme amount at evaluated pH and aeration shift conditions (p?<?0.05).     

Cytoglobin: a potential marker for adipogenic differentiation in preadipocytes in vitro

Obesity, mainly characterized by the excess fat storage, is a global health problem resulting in serious morbidity and mortality. Identification of molecular mechanisms in adipogenic differentiation pathway might lead to development of new strategies for diagnosis, prevention and therapy of obesity and associated diseases. Discovery of new genes and proteins in the differentiation pathway could help to understand the key specific regulators of the adipogenesis. Cytoglobin (Cygb), identified as a new globin family member protein, is expressed in various tissues. Although its interaction with oxygen and nitric oxide indicates the potential role in antioxidant pathways, the exact role remains unclear. In the current study, expression level of Cygb was determined in proliferating and differentiating 3T3-F442A cells by gene expression and protein expression analysis. Results revealed that Cygb expression up-regulated in differentiated cells in parallel with adipogenic differentiation markers; PPARγ, CEBPα and FABP4 expressions. Besides, Cygb overexpression in preadipocytes contributed to the adipogenic differentiation as verified by detection of higher lipid droplets and increased PPARγ, CEBPα and FABP4 expressions with respect to control cells. These findings will shed light on the unknown roles of Cygb in adipogenesis and obesity.     

Multiple-site trimethylation of ribosomal protein L11 by the PrmA methyltransferase

Ribosomal protein L11 is a universally conserved component of the large subunit, and plays a significant role during initiation, elongation, and termination of protein synthesis. In Escherichia coli, the lysine methyltransferase PrmA trimethylates the N-terminal alpha-amino group and the epsilon-amino groups of Lys3 and Lys39. Here, we report four PrmA-L11 complex structures in different orientations with respect to the PrmA active site. Two structures capture the L11 N-terminal alpha-amino group in the active site in a trimethylated post-catalytic state and in a dimethylated state with bound S-adenosyl-L-homocysteine. Two other structures show L11 in a catalytic orientation to modify Lys39 and in a noncatalytic orientation. The comparison of complex structures in different orientations with a minimal substrate recognition complex shows that the binding mode remains conserved in all L11 orientations, and that substrate orientation is brought about by the unusual interdomain flexibility of PrmA.     

PON1 55 and 192 Gene Polymorphisms in Type 2 Diabetes Mellitus Patients in a Turkish Population

Diabetes mellitus is a multifactorial metabolic disease, caused by the complete or relative absence of insulin hormone, which results in the deterioration of carbohydrate, protein, and lipid metabolism. The PON1 55 and 192 polymorphisms have been reported to be associated with type 2 diabetes and its complications. In this study, the involvement of the PON1 55 and 192 polymorphisms and paraoxonase enzyme activity in diabetic complications was assessed. The MM and QQ genotypes were the most frequent in complications of type 2 diabetes in both of the polymorphisms. PON enzyme activity was lower in the type 2 diabetes group with respect to the control group. Regarding both genotypes and enzyme activity, correlations were found between the PON1 55 and 192 genotypes and diabetic complications. This study thus helps to outline a genotype?Cphenotype relation for the PON1 gene in a Turkish population.