Ghrelin in plants: what is the function of an appetite hormone in plants?

In the present work, we provide compelling evidence for the expression of a ghrelin-like peptide hormone that has only been associated with animals, in various plant tissues. Ghrelin, the appetite stimulating hormone, has been identified from a number of different species including humans, rat, pig, mouse, gerbil, eel, goldfish, bullfrog and chicken. The study here was conducted using an immunohistochemistry assay to screen whether plants have any ghrelin immunoreactivity. In this respect, Prunus x domestica L. and Marus alba were examined. Immunohistochemistry results showed that there is a strong human ghrelin immunoreactivity substance in the parenchyma cells of these plants. This was entirely unexpected since this hormone was considered to be present solely in animals. Thus, this study is the first to report the presence of a peptide with ghrelin-like activity in plants, a finding that has only been observed in the animal kingdom. RIA analysis confirmed that these plants contain significant amounts of this substance. Furthermore, reverse-phase HPLC analyses of plant extracts showed an elution characteristic of the peptide identical to that of human ghrelin. In general, fruit from both plants had higher levels of the peptide than the vegetative parts.     

Engineering microalgae for water phosphorus recovery to close the phosphorus cycle

As a finite and non-renewable resource, phosphorus (P) is essential to all life and crucial for crop growth and food production. The boosted agricultural use and associated loss of P to the aquatic environment are increasing environmental pollution, harming ecosystems, and threatening future global food security. Thus, recovering and reusing P from water bodies is urgently needed to close the P cycle. As a natural, eco-friendly, and sustainable reclamation strategy, microalgae-based biological P recovery is considered a promising solution. However, the low P-accumulation capacity and P-removal efficiency of algal bioreactors restrict its application. Herein, it is demonstrated that manipulating genes involved in cellular P accumulation and signalling could triple the Chlamydomonas P-storage capacity to ~7% of dry biomass, which is the highest P concentration in plants to date. Furthermore, the engineered algae could recover P from wastewater almost three times faster than the unengineered one, which could be directly used as a P fertilizer. Thus, engineering genes involved in cellular P accumulation and signalling in microalgae could be a promising strategy to enhance P uptake and accumulation, which have the potential to accelerate the application of algae for P recovery from the water body and closing the P cycle.     

Gadolinium-Loaded Polychelating Polymer-Containing Cancer Cell-Specific Immunoliposomes

Liposome loading with Gd via the membrane-incorporated polychelating amphiphilic polymers (PAPs) significantly increases the Gd content and relaxivity (T1 parameter) of PEGylated liposomes, which can be used as contrast agents for magnetic resonance imaging (MRI). Here, we demonstrate that such Gd-containing liposomes can be additionally modified with the monoclonal anticancer antibody 2C5 (mAb 2C5) possessing the nucleosome(NS)-restricted specificity via the PEG spacer. Liposome-bound antibody preserves its specific activity (ELISA) and such Gd-loaded PEGylated 2C5-immunoliposomes specifically recognize various cancer cells in vitro and target an increased amount of Gd to their surface compared to antibody-free Gd-liposomes or Gd-liposomes modified with tumor nonspecific antibody. Gd-loaded cancer cell-targeted immunoliposomes may represent promising agents for enhanced tumor MRI.     

Basal damage and oxidative DNA damage in children with chronic kidney disease measured by use of the comet assay

One consequence of chronic kidney disease (CKD) is an elevated risk for cancer. There is sufficient evidence to conclude that there is an increased incidence of at least some cancers in kidney-dialysis patients. Cancer risk after kidney transplantation has mainly been attributed to immunosuppressive therapy. There are no data evaluating DNA damage in children with CKD, in dialysis patients, or following kidney transplantation. In this study, the comet assay and the enzyme-modified comet assay - with the use of endonuclease III (Endo III) and formamidopyrimidine glycosylase (FPG) enzymes - were conducted to investigate the basal damage and the oxidative DNA damage as a result of treatment in peripheral blood lymphocytes of children. Children at various stages of treatment for kidney disease, including pre-dialysis patients (PreD) (n=17), regular hemodialysis patients (HD) (n=15), and those that received kidney transplants (Tx) (n=17), comprised the study group. They were compared with age- and gender-matched healthy children (n=20) as a control group. Our results show that the %DNA intensity, a measure of basal damage, was significantly increased in children with CKD (mean ± SD) (5.22 ± 1.57) and also in each of the PreD, HD, and Tx groups [(4.92 ± 1.23), (4.91 ± 1.35), and (5.79 ± 1.94), respectively, vs the healthy children (2.74 ± 2.91) (p<0.001). Significant increases in oxidative DNA damage were only found in the FPG-sensitive sites for the PreD and Tx groups, compared with control and HD groups (p<0.05), suggesting that basal DNA damage was more evident for the PreD, HD, and Tx groups. The findings of the present study indicate a critical need for further research on genomic damage with different endpoints and also for preventive measures and improvements in treatment of pediatric patients, in order to improve their life expectancy.     

A new set up for multi-analyte sensing: at-line bio-process monitoring

A multi-analyte sensing device is described, for simultaneous at-line monitoring of glucose, ethanol, pO?-value and cell density. It consists of a dual biosensor, a modified microscope and a fiber optical pO?-sensor that are integrated into a flow analysis (FA) system. The biosensor is based on a conventional thin layer flow-through cell equipped with a gold (Au) dual electrode (serial configuration). The biosensors with no cross-talking were produced by modifying the electrochemical transducers. Each Au surface was initially modified by self-assembled monolayer (SAM) of cysteamine. Alcohol oxidase (AOx) and pyranose oxidase (PyOx) were immobilized each onto a gold surface by means of PAMAM (polyamidoamine) dendrimer via glutaraldehyde cross-linking. The responses for glucose and ethanol were linear up to 0.5 mM. The operational stability of the biosensors was very promising, after 11 h continuous operation, only 6.0% of the initial activity was lost. The potential of the described biosensor was demonstrated by parallel determination of ethanol and glucose in yeast fermentation process. Simultaneously the cell density of the culture was monitored with an in situ microscope (ISM), which was integrated into the FA system. Both the used in situ microscope and the image processing algorithm used for the analysis of the acquired image data are described. Furthermore the pO?-value was monitored using a fiber optical sensor, which was embedded in a flow cell. The multi-sensor device allows the at-line monitoring of several process values without the need for further sampling or time consuming offline measurements.     

Evaluation of oxysterol levels of patients with silicosis by LC–MS/MS method

Molecular and Cellular Biochemistry - Aberrant structural formations of Cu/Zn superoxide dismutase enzyme (SOD1) are the probable mechanism by which circumscribed mutations in the SOD1 gene cause...     

The effect of vaginal candidiasis on the levels of the oxidative biomarkers in plasma and tissue samples of diabetic rats

The aim of this study is to determine the relation between diabetes and vaginal candidiasis in terms of oxidative biomarker levels in a vaginal candidiasis model of the diabetic rats by evaluating malondialdehyde (MDA), sulphydrile groups or glutathione (RSH), and ascorbic acid (C vit) levels. All rats were randomly divided into five groups. All of the groups were observed for 21 days. In the treated diabetes groups, MDA (0.90, 0.68 nmol/ml and 3.78, 3.79 nmol/g tissue, plasma and vaginal tissue, respectively) and RSH (227, 171 nmol/100 ml 0.38, 0.37 μmol/g tissue, plasma and vaginal tissue, respectively) levels were found to be decreased while the levels of C vit were found to be increased (0.49, 0.37 μmol/l 2.39, 2.01 nmol/g tissue plasma, and vaginal tissue, respectively) (P < 0.05). In the groups of untreated diabetes, vaginal candidiasis were found to be more serious and oxidative biomarkers were found to be increased (MDA 1.30, 1.26 nmol/ml and 7.82, 2.37 nmol/g tissue and RSH 258, 145 nmol/100 ml and 0.31, 0.46 μmol/g tissue) while the antioxidant C vit levels were found to be decreased (0.24, 0.17 μmol/l 1.33, 2.66 nmol/g tissue) (P < 0.05). RSH, plasma MDA, blood glucose, and tissue MDA levels of vaginal candidiasis embedeled diabetic rats, were found to be higher than those in untreated diabetic and untreated vaginitis enbedeled rats ‹P < 0.05’. Vaginal candidiasis caused oxidative stress in diabetic rats working together. Systemic oxidative stress biomarkers were found to be affected from vaginal candidiasis although it was a local mucosal infection. This study was presented as a poster in the conference of ‹2nd Trends in Medical Mycology, 23–26 October 2005, Berlin, Germany’.