Month: January 2020

Penicillin and ampicillin are covalently attached to expanded polytetrafluoroethylene through a PEG-spacer to develop antimicrobial surface. 2-Methoxy-29,4 9-dichloro chalcone when mixed with marine paint and coated on polycarbonate, glass fiber reinforced plastic and polymethylmethacrylate prevents the formation of Vibrio natriegens biofilm. However, in the above cases, antimicrobial property is exhibited as long as the compound is present on the surface. Leaching out of the compound from the surface leads to loss of antimicrobial property and hence this strategy is not suitable for implants that need to stay in the body for longer periods of time. In addition, development of drug resistance by the biofilm forming microbes is another serious problem which strongly requires strategies that do not use antibiotics. Subtilisin, an enzyme, when immobilized on polycaprolactam exhibits antimicrobial activity against both Gram positive as well as negative microbes. Silver nanocomposites also exhibit such properties. Enzymes including oxidoreductases, transferases, hydrolases, esterases, isomerases and lyases have been reported to exhibit antibacterial property. However, their mode of action and their effects in most of the cases have not been elucidated fully. Lipase, a hydrolytic enzyme, exhibits antimicrobial and antifouling properties, but its mechanism of action is not studied so far. Polycaprolactam is a polymer with six amide bonds which lie in the same direction, resembling natural polypeptide. It is a porous polymer and is used as a scaffold for biomedical applications. The significance of porous biomaterial for the construction of implants is stated in a work by Doi et al. Such a material helps in osseointegration by forming a direct interface between the implant and bone without the intervening soft tissues. Such implants are also more prone to the growth and proliferation of microbes. These implants, in addition to supporting a damaged biological structure, could be made antimicrobial by incorporating an antimicrobial agent and made biosorbable by using a biodegradable polymer, which would prevent the need for another surgery to remove the implant. Enzymes are immobilized on these porous surfaces and used as biologically functionalized surfaces in enzyme delivery, diagnostic assays and bioreactors. Langmuir Blodgett Deposition is a useful technique to design thin solid films at the molecular level. When films are deposited on a porous surface, the monolayer will bridge the voids, supported by a layer of water. When the water drains or dries, the film collapses. So, coating of molecules is improper and non uniform on porous surfaces. Maintaining the activity of protein and enzyme in the Langmuir-Blodgett monolayer is one more disadvantage that has not been completely overcome. In the present study, Layer by Layer formation of highly active and stable biocatalytic film of cross linked lipase.

A recent study also demonstrated that the increases in SREBP-1 and ChREBP-1-dependent fatty acid synthesis pathways, which are responsible for converting excess carbohydrate to fatty acid for long-term storage, are paralleled by markedly decreased PPAR-a, PPAR-d, and their target enzyme, acyl-CoA oxidase, which mediate fatty acid oxidation. It has been known that SREBP-1c is strongly linked to diabetic nephropathy, in which hyperglycemia activates mesangial SREBP-1c, ROS and mesangial proliferation and glomerular fibrosis. In the current study, fenofibrate decreased SREBP-1 and ChREBP-1 and increased phosphorylation of ACC, which correlated with decreased lipid contents in the kidney. We also demonstrated that high-glucose treatment of mesangial cells induced the expression of genes involved in fatty acid synthesis, such as those encoding SREBP-1 and ChREBP-1. Fenofibrate reversed all of these changes, suggesting that the renoprotective impact of fenofibrate may be mediated by shifting the gene expression profile of the cells to a state that inhibits lipogenesis. To date it has been known that PGC-1a is inactivated by the phosphorylation of Akt and Akt can have a negative impact on the PGC-1a expression via inactivation of the FoxOs factors, FoxO1 and FoxO3a which act as transcriptional regulators of PGC-1a expression. In obese or diabetic states, the FoxO1 and FoxO3a-dependent gene expression promotes some of the deleterious characteristics associated with hyperglycemia, glucose intolerance and lipotoxicity. Currently, it is not known whether there are differences in the activation levels of separate FoxO factors, particularly in different tissues. The renal expression of phospho-Ser256 FoxO1 and phosphor-Ser253 FoxO3a by fenofibrate treatment in overfed spontaneously hypertensive rats showed that phospho-Ser253 FoxO3a was strongly expressed in the cytoplasm of podocytes in the glomerulus and the collecting tubules, while phospho-Ser256 FoxO1 was strongly expressed in the proximal tubules and very weakly expressed in the glomerulus in the immunohistochemical staining. In this study, fenofibrate treatment markedly decreased the renal expression of phosphor-Ser253 FoxO3a, whereas it did not have any effect on the phospho-Ser256 FoxO1 expression in the diabetic mice. The inactivation of PI3K/Akt and the activation of FoxO3a were one of the main pathways to reduce lipoapoptosis and oxidative stress as represented by the decrease of urinary 8-epi PDF2a levels, which resulted in increases of anti-apoptotic BCL-2 and the antioxidants and a decrease of the pro-apoptotic gene BAX in diabetic mice. Interestingly, there is a strong overlap in the genes transcriptionally regulated by AMPK and those by PGC-1a, hence suggesting that PGC-1a might be an important mediator AMPK-induced gene expression. Supporting this hypothesis, AMPK activation leads to increased PGC-1a expression, and AMPK requires PGC-1.

Spatial and quantitative accumulation of the eight forms has been shown to vary during barley seed development, with tissue-specific form distribution, and relative form ratios shifting throughout early kernel formation. Kinetics of tocochromanol forms suggests specific roles throughout seed development and germination, requiring precise control of individual genes. In this study, major loci affected multiple forms, reflecting activity of genes at key intersections of the tocochromanol biosynthetic pathway. The barley 6H QTL influencing cT and dT corresponded to a rice region containing VTE4, which converts c to a and d to b, accounting for the forms mapped to this locus. Minimal FA sequence variation was observed within the VTE4 gene and its upstream regulatory region, although observed polymorphism affected significant regions, modifying two promoter motifs and causing an amino acid change. Based on VTE4 sequences of two FA RILs with divergent levels of c and d forms, it does not appear that the intronic indel plays a role in VTE4 activity. However, the indel is heritable, evidenced by the 1:1 ratio produced when genotyping the FA population with the molecular marker based on this polymorphism. Despite the sequence similarities, expression patterns of VTE4 differed between Falcon and Azhul, with cold temperatures inducing increased expression primarily in Falcon shoot tissue and Azhul embryo tissue. Since promoter sequence polymorphism affected regions involved in low-temperature response, these motifs may affect spatial expression of VTE4. Future work should be performed to explore this possibility, as well as to study additional factors affecting VTE4 gene expression such as methylation patterns and involvement of microRNA. The QTL accounting for a majority of the phenotypic variance in this study were detected on chromosome 7H. Both regions influence accumulation of multiple tocotrienol forms, the more abundant tocochromanol in barley and some other small grains. The QTL affecting all four T3 forms corresponded to the rice chromosome 6 region containing VTE2, a gene reported to preferentially add the phytyldiphosphate side chain to form tocopherols, with analogous formation of tocotrienols by HGGT. Dicots appear to lack a prenyltransferase recognizing geranylgeranyl diphosphate, hence they produce little or no tocotrienols. Monocots, however, appear to express two distinct prenyltransferases, one favoring phytyldiphosphate as substrate, the other favoring genanylgeranyl diphosphate. In this study, a major QTL on chromsosome 7H corresponded with increased accumulation of all four tocotrienol forms. Barley SNP sequences within this QTL are syntenous with a rice chromosome 6 region containing VTE2, closely neighboring a region containing HGGT. In this study, barley HGGT corresponded with the rice region containing VTE2, and a barley VTE2 locus was not identified, suggesting minimal activity of this enzyme.

principally of digestive organs. An impairment of larval survival and reproductive development anomalies and increases on the lysosomal destabilization in oysters’ hepatopancreas have been observed. Recently, in vitro assays have shown that HAB species such as Karenia brevis, Dinophysis acuminata, Alexandrium sp. affect viability and phagocytosis in bivalves’ immune cells significantly. Consequently studying the effects of harmful algae on bivalves’ immune system has recently become an area of great interest for researchers; various publications have demonstrated that hemocytes, as well as immune parameters, may be activated or modulated under the presence of several species of toxic microalgae. However, few studies have addressed gene expression changes in C. gigas in response to toxic algal exposure or to their toxins. Currently, a mussel cDNA digestive gland microarray fed for five weeks with OA contaminated nutrient reported a general upregulation of transcripts coding for stress proteins and those involved in cellular synthesis. The Pacific oyster C. gigas is a suspension-feeding bivalve mollusk, of great interest as a study model given its ecological, economic, public health, and genomic relevance because it has a completely sequenced genome. Medical advances have increased the survival rates of premature babies; however, blindness, deafness etc.. In later life, they may face complications such as motor and sensory impairment, learning difficulties and behavioral issues. Prematurity leads to an immediate and long term emotional and financial burden to families, communities and the health care system. Threatened preterm labor is defined as persistent premature uterine contractions between 20 and 37 weeks of gestation and may include other symptoms such as pelvic pressure, backache, increased vaginal discharge, menstrual-like cramps, bleeding/show and shortened cervix. Treatment of TPTL involves administration of tocolytic agents to temporarily inhibit uterine contractions and prolong the pregnancy up to 48 hours. This 48 hour window serves to achieve both the benefits of corticosteroid administration on fetal lung maturation as well as the ability to transport the woman to a tertiary hospital with advanced neonatal facilities. Generally, labor contractions in the majority of TPTL women will cease and they often continue their pregnancies to term ; while approximately 5% of these women will progress into true PTL and deliver a premature baby within 10 days. Thus, women in “false labor” are subjected to unnecessary hospitalization, medical intervention, psychologic stress, exposed to drug side effects and contribute to healthcare costs. For example, although corticosteroids augment fetal lung maturity and reduce respiratory distress syndrome, intraventricular hemorrhage and neonatal mortality in premature infants, their longer term side effects remain unclear.

Substrate diffusion through cell membranes also accounted for the observed time-dependency of bioluminescent reaction rates, which by virtue of the induced spatial heterogeneities resembled fractallike reaction kinetics. The afore-mentioned model fits the experimental data points with good accuracy, thereby enabling reliable quantitative insights into the bioluminescence reaction kinetics for both cell lysates and intact cells. Microscale measurements of oxygen concentration were performed by integration of fluorescent oxygen sensitive microbeads that we previously developed. Stable read-outs of oxygen concentration over a time period of 3 days were obtained for control gels in which no cells were embedded. Radial oxygen concentration profiles from cell-seeded hydrogels displayed a gradual decrease towards the center with an averaged availability of oxygen that increased over time. Dynamic time point measurements of the average photon flux emitted from the cell-seeded hydrogels revealed the presence of a fast bioluminescence intensity peak that fades away slowly with a decaying signal that was detectable for several hours. Peak intensities reached maximum values after 2 days of cultivation and decreased gently with longer cultivation time. These results did however not entirely correlate to the quantitative DNA and viability measurements, representing the active bioluminescent cell population and clearly being oxygenindependent readouts. To decouple bioluminescence signal reshaping caused by oxygen availability from the spatial distribution of luciferase activity, we removed cell respiration in our model, hence maintaining a saturated oxygen level within the hydrogel and therefore oxygen-independent bioluminescence signal intensities. A prominent role for oxygen in reshaping the bioluminescence signal was clearly observed. When saturated oxygen conditions were simulated the obtained peak signal intensities matched closely the cell activity measurements. Radial profiles of the bioluminescence signal emitted from encapsulated 293T cells indicated high activity near the hydrogel edge at early time points that gradually leveled off towards the center after longer measurement times. With increasing cultivation times the observed effect of high edge activity became more pronounced and was in good agreement with our simulation results. Combined, these data show a strong influence of oxygen availability on the activity of luciferase reporter cells which should be taken into account when intrinsic measurements and error-free interpretations of bioluminescence intensity are pursued. Obesity, a state of excessive adipose tissue, has long been known to be a risk factor for the development of cardiovascular disease. Adipose tissue has been traditionally considered a fat-storage organ, but is now known to have an active role in systemic metabolism through the active secretion of adipokines.