EVALUATION OF ANTIOXIDANT POTENTIAL OF SPILANTHES PANICULATA

Objective: The present study was conducted to evaluate the antioxidant potential of Spilanthes paniculata.Methods: The antioxidant activity of three different extracts (ethanol, methanol and chloroform extracts) of the whole plant was evaluated by determining total antioxidant capacity using phospho molybdenum method and total flavonoid content by Aluminum chloride colorimetric method.Results: Preliminary results from phytochemical screening showed that ethanol, methanol and chloroform extracts of S. paniculata contain flavonoids along with other phyto chemicals in moderate to high amounts. The extracts were then evaluated for total antioxidant capacity using ascorbic acid as the standard. The total antioxidant capacity of ethanol, methanol and chloroform extracts was found to be 153.54±1.343, 157.97±6.713 and 200.38±4.028 mg/g of plant extract which were expressed as Ascorbic Acid Equivalents (AAE). Also total flavonoid content was determined and was expressed as quercetin equivalents (QE). The content of flavonoid compounds in ethanol, methanol and chloroform extract was estimated to be 101.58±55.919, 121±74.318 and 51.07±19.121 mg/g dry weight of extract.Conclusion: Based on these findings, it can be concluded that the significant antioxidant potential of the extracts might be attributed to moderate to high amount of flavonoids present in the extract.Â

Evaluation of electropolished stainless steel electrodes for use in DC high voltage photoelectron guns

DC high voltage photoelectron guns are used to produce polarized electron beams for accelerator-based nuclear and high-energy physics research. Low-level field emission (similar to nA) from the cathode electrode degrades the vacuum within the photogun and reduces the photoelectron yield of the delicate GaAs-based photocathode used to produce the electron beams. High-level field emission (\u3e mu A) can cause significant damage the photogun. To minimize field emission, stainless steel electrodes are typically diamond-paste polished, a labor-intensive process often yielding field emission performance with a high degree of variability, sample to sample. As an alternative approach and as comparative study, the performance of electrodes electropolished by conventional commercially available methods is presented. Our observations indicate the electropolished electrodes exhibited less field emission upon the initial application of high voltage, but showed less improvement with gas conditioning compared to the diamond-paste polished electrodes. In contrast, the diamond-paste polished electrodes responded favorably to gas conditioning, and ultimately reached higher voltages and field strengths without field emission, compared to electrodes that were only electropolished. The best performing electrode was one that was both diamond-paste polished and electropolished, reaching a field strength of 18.7 MV/m while generating less than 100 pA of field emission. The authors speculate that the combined processes were the most effective at reducing both large and small scale topography. However, surface science evaluation indicates topography cannot be the only relevant parameter when it comes to predicting field emission performance. (C) 2015 American Vacuum Society

Combining the Specific Anti-MUC1 Antibody TAB004 and Lip-MSA-IL-2 Limits Pancreatic Cancer Progression in Immune Competent Murine Models of Pancreatic Ductal Adenocarcinoma

Immunotherapy regimens have shown success in subsets of cancer patients; however, their efficacy against pancreatic ductal adenocarcinoma (PDA) remain unclear. Previously, we demonstrated the potential of TAB004, a monoclonal antibody targeting the unique tumor-associated form of MUC1 (tMUC1) in the early detection of PDA. In this study, we evaluated the therapeutic benefit of combining the TAB004 antibody with Liposomal-MSA-IL-2 in immune competent and human MUC1 transgenic (MUC1.Tg) mouse models of PDA and investigated the associated immune responses. Treatment with TAB004 + Lip-MSA-IL-2 resulted in significantly improved survival and slower tumor growth compared to controls in MUC1.Tg mice bearing an orthotopic PDA.MUC1 tumor. Similarly, in the spontaneous model of PDA that expresses human MUC1, the combination treatment stalled the progression of pancreatic intraepithelial pre-neoplastic (PanIN) lesion to adenocarcinoma. Treatment with the combination elicited a robust systemic and tumor-specific immune response with (a) increased percentages of systemic and tumor infiltrated CD45+CD11b+ cells, (b) increased levels of myeloperoxidase (MPO), (c) increased antibody-dependent cellular cytotoxicity/phagocytosis (ADCC/ADCP), (d) decreased percentage of immune regulatory cells (CD8+CD69+ cells), and (e) reduced circulating levels of immunosuppressive tMUC1. We report that treatment with a novel antibody against tMUC1 in combination with a unique formulation of IL-2 can improve survival and lead to stable disease in appropriate models of PDA by reducing tumor-induced immune regulation and promoting recruitment of CD45+CD11b+ cells, thereby enhancing ADCC/ADCP

The mutation that makes Escherichia coli resistant to λ P gene-mediated host lethality is located within the DNA initiator gene dnaA of the bacterium

Earlier, we reported that the bacteriophage λ P gene product is lethal to Escherichia coli, and the E. coli rpl mutants are resistant to this λ P gene-mediated lethality. In this paper, we show that under the λ P gene-mediated lethal condition, the host DNA synthesis is inhibited at the initiation step. The rpl8 mutation maps around the 83 min position in the E. coli chromosome and is 94% linked with the dnaA gene. The rpl8 mutant gene has been cloned in a plasmid. This plasmid clone can protect the wild-type E. coli from λ P gene-mediated killing and complements E. coli dnaAts46 at 42° C. Also, starting with the wild-type dnaA gene in a plasmid, the rpl-like mutations have been isolated by in vitro mutagenesis. DNA sequencing data show that each of the rpl8, rpl12 and rpl14 mutations has changed a single base in the dnaA gene, which translates into the amino acid changes N313T, Y200N, and S246T respectively within the DnaA protein. These results have led us to conclude that the rpl mutations, which make E. coli resistant to λ P gene-mediated host lethality, are located within the DNA initiator gene dnaA of the host

Arsenic (As) Contamination in Different Food and Dietary Samples from Several Districts of Bangladesh and Arsenic (As) Detection, Mitigation and Toxicity Measurement and impact of Dietary Arsenic Exposure on Human Health

Objective: To determine the level of arsenic concentration in vegetables and other food categories in three selected areas of Pabna district and to estimate quantitatively the dietary arsenic exposure in one of the arsenic contaminated areas of Bangladesh.Materials and Methods: The study was conducted in CharRuppur, Char mirkamari and Lakshmikunda village of IshwardiUpzila in Pabna district. Ishwardi (Town) consists of 12 wardsand 37 mahallas. Arsenic was detected in the ADM Lab,Department of Pharmacology, Bangladesh Agricultural University, Mymensingh with Hydride Generation Atomic Absorption Spectrophotometer (HG-AAS; PG-990, PG Instruments Ltd. UK). Arsenic was detected by forming AsH3 at below pH 1.0 after the reaction of As with a solution of sodiumborohydride (NaBH4), sodium hydroxide (NaOH, M=40,000g/mol,) and 10% HCl. In this test, standard was maintained asAsV ranging from 0 to 12.5 μg/L.Results: A total of 120 vegetable samples, 15 rice samples and15 fish samples were collected from five different markets ofthree different villages of Pabna district and were tested forarsenic concentration. Findings demonstrated that the mean concentration of As in leafy vegetables (0.52 μg g-1) was significantly higher compared to those found in fruity (0.422μg g-1) and root & tuber vegetables (0.486 μg g-1).Conclusion: Underground Contaminated water was the major source for the As contamination of various products in Pabna.The arsenic levels were found higher among the leafy vegetables samples in comparison to fruit and root & tuber vegetables. Further studies will be conducted to search the genetic risk factors of arsenic toxicity in the population of the mostly affected people