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After acute myocardial infarction (AMI), neutrophils are recruited to the affected myocardium. Hypochlorous acid (HOCl) produced by neutrophil myeloperoxidase (MPO) damages cardiomyocytes and potentially expands the primary infarct. Rat cardiomyocyte-like cells were incubated with isolated human neutrophils treated with chemical activators in the absence or presence of nitroxide 4-methoxy-Tempo (MetT; 25 μM) for 4, 6 or 24 h; studies with reagent HOCl served as positive control. Treating cardiomyocytes with activated neutrophils or reagent HOCl resulted in a marked increase in protein tyrosine chlorination and a decline in protein tyrosine phosphatase (PTP) activity. On balance our data also supported an increase in phosphorylation of MAPK p38 and ERK1/2 suggestive of an intracellular hyperphosphorylation status and this was accompanied by decreases in cell viability, as judged by assessing caspases-3/7 activity. For cells exposed to activated neutrophils receptor-mediated uptake of transferrin decreased although total matrix metalloproteinase (MMP) activity was unaffected. Addition of MetT ameliorated protein tyrosine chlorination, decreased MAPK activity and restored receptor-mediated transferrin uptake and PTP activity in cardiomyocytes. Overall, adverse effects of neutrophil-derived HOCl on cultured cardiomyocytes were ameliorated by MetT suggesting that nitroxides may be beneficial to inflammatory pathologies, where neutrophil recruitment/activation is a prominent and early feature.

Strong porous permeable ceramic is studied, prepared by selection of grain size compositions with filler of electromelted corundum grades F600 (100 – 200 μm), F360 (40 – 60 μm), and F120 (10 – 20 μm). The strengthening binders used are very fine corundum powder (~2 μm), alloyed with 0.25 wt.% MgO; a mixture of SiC (particle size 3 – 4 μm) and MgO (particle size 1 – 2 μm) in a ratio of 2:1. Specimens in the form of bars 60 × 15 × 5.5 mm are prepared by uniaxial semidry compaction under a pressure of 50 MPa (for single fraction compositions) and 25 MPa (for three-fraction compositions). Specimens are fired in air at temperatures from 1350 to 1550°C. Specimen open porosity varies from 28 to 43%, and ultimate strength in bending from 1 to 36 MPa. The best strength is obtained using a binder in the system SiC–MgO (5 wt.% binder above 100% of filler, σben = 36 MPa, and open porosity is 30%).

Porous permeable ceramic is prepared from electromelted corundum (EMC) with fineness of about 0.5 mm with added porcelain. Compositions are prepared with different ratios of EMC/porcelain: 99/1, 97/3, 95/5, 93/7, and 90/10. Specimens in the form of bars with a size of 40 × 7 × 6.5 mm are prepared by uniaxial semidry compaction under a pressure of 25 and 50 MPa and fired at 1350 and 1450°C. Specimen open porosity varies from 22 to 30%, and ultimate strength in bending from 1.1 to 9.3 MPa. Porous ceramic is promising for filters and ceramic membrane substrates.

The strengthened porous ceramics was investigated in the article which had been obtained by the grain composition mix design using the electro-fused corundum aggregates: F600 (particle size is 100‒200 micron); F360 (40‒60 micron) and F120 (10‒20 micron). In the capacity of strengthening binders the highly dispersed corundum powders (about 2 micron) doped with 0,25 wt. % of MgO; and the mixture of SiC powder (3‒4 micron) and of MgO powder (1‒2 micron) in the ratio of 1:2 were used. The test-beams of the size 60×15×5,5 mm were obtained by means of uniaxial semi-dry compacting under the pressure of 50 MPa (for mono-fractional compositions) and of 25 MPa (for three-fractional compositions). The samples were burnt on the air at the temperatures from 1350 to 1550 °C. The open porosity varied from 28 to 43 %, the ultimate bending strength varied from 1 to 36 MPa. The highest strength was attained when the SiC‒MgO binder was used (5 wt. % of the binder over 100 % of the aggregate, the ultimate bending strength was 36 MPa, the open porosity was 30 %). Ref. 12. Tab. 5.

The effects of twoprocessing methods (soaking and wilting) and three processing times (12, 24 and48h) on the hydrocyanic acid potential (HCNp) oftwo varieties of cassava tuber were evaluated. The initial HCNp content in the Redcassava Red (165.04 mg/kg DM basic) was higher than White cassava (103.22 mg/kgDM basic). However, both processing methods were equally effective in reducingthe HCNp content in both of Red and White cassava varieties. Regarding thevarieties, white cassava possessed the lower HCNp (p0.05) of processing methods on HCNp andits reduction rates of both cassava varieties were found, however thesignificant effect (p

Activated neutrophils release myeloperoxidase that produces the potent oxidant hypochlorous acid (HOCl). Exposure of the oxygen transport protein horse heart myoglobin (hhMb) to HOCl inhibits Iron III (Fe(III))-heme reduction by cytochrome b5 to oxygen-binding Iron II (Fe(II))Mb. Pathological concentrations of HOCl yielded myoglobin oxidation products of increased electrophoretic mobility and markedly different UV/Vis absorbance. Mass analysis indicated HOCl caused successive mass increases of 16 a.m.u., consistent serial addition of molecular oxygen to the protein. By contrast, parallel analysis of protein chlorination by quantitative mass spectrometry revealed a comparatively minor increase in the 3-chlorotyrosine/tyrosine ratio. Pre-treatment of hhMb with HOCl affected the peroxidase reaction between the hemoprotein and H2O2 as judged by a HOCl dose-dependent decrease in spin-trapped tyrosyl radical detected by electron paramagnetic resonance (EPR) spectroscopy and the rate constant of 2,2&prime, azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) oxidation. By contrast, Mb catalase-like antioxidant activity remained unchanged under the same conditions. Notably, HOCl-modification of Mb decreased the rate of ferric-to-ferrous Mb reduction by a cytochrome b5 reductase system. Taken together, these data indicate oxidizing HOCl promotes Mb oxidation but not chlorination and that oxidized Mb shows altered Mb peroxidase-like activity and diminished rates of one-electron reduction by cytochrome b5 reductase, possibly affecting oxygen storage and transport however, Mb-catalase-like antioxidant activity remains unchanged.

Isolation of Erwinia chrysanthemi rhizome rot bacteria from infected rhizome of banana plants in Twentay Township, Yangon Region was conducted in Microbiology Laboratory, Department of Botany, University of Yangon. Antibacterial activity on Erwinia chrysanthemi from the nine selected plant species and the four chemical bactericides were evaluated by paper disc diffusion methods. The solvent extracts of the eight plant samples Capsicum annuum L., Curcuma longa L., Languas galangal L. Stuntz, Nicotiana tobacum L., Piper nigrum L., Synzygium aromaticum L. Merr. Perry, Zingiber barbatum Wall. and Zingiber officinale Rose indicated bioactivity on E. chrysanthemi. However, the extracts of Piper betel L. did not show antibacterial activity on E. chrysanthemi. Chemical bactericides Agri mycin 17, Ariston, Bio save and Blocker 4E showed the weak activity on E. chrysanthemi. Ko Tin | Sithu Aung Min "Effects of Plant Extracts and Commercial Bactericides on Erwinia Chrysanthemi (Rhizome Rot Bacteria) in Banana Plants" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-5 , August 2019, URL: https://www.ijtsrd.com/papers/ijtsrd27862.pdf

UTCC International Journal of Business and Economics, 11, 1, 186-215

A study is made of a strong porous ceramic based on granular mixes of a filler—electrofused corundum with particle sizes of 2 – 3 and 0.5 mm (95 wt.% of the mix) — and a porcelain binder (5 wt.%). Several mixes were prepared with different values for the 2 – 3 mm/0.5 mm ratio of filler-particle sizes: 0/95, 35/60, 40/55, 45/50, 50/45, and 95/0. The specimens were pressed at pressures of 25, 50 and 100 MPa and fired at temperatures of 1350 and 1450°C. The sintered specimens ranged from 19 to 143 MPa in ultimate flexural strength and 17 to 26% in open porosity. The results are attributed to the formation of a framework in the semifinished product along with regions outside the framework. The new porous permeable ceramic is promising for use in the form of filters and supports for ceramic membranes.

Dengue virus (DENV) infection remains a major public health concern in many parts of the world, including Southeast Asia and the Americas. Sri Lanka experienced its largest dengue outbreak in 2017. Neurological symptoms associated with DENV infection have increasingly been reported in both children and adults. Here, we characterize DENV type 2 (DENV-2) strains, which were isolated from cerebrospinal fluid (CSF) and/or serum of patients with dengue encephalitis. Acute serum and CSF samples from each patient were subjected to dengue-specific non-structural protein 1 (NS1) antigen test, IgM and IgG enzyme-linked immunosorbent assay (ELISA), virus isolation, conventional and real-time polymerase chain reaction (PCR), and next-generation sequencing (NGS). Among the 5 dengue encephalitis patients examined, 4 recovered and 1 died. DENV-2 strains were isolated from serum and/or CSF samples of 3 patients. The highest viral genome levels were detected in the CSF and serum of the patient who succumbed to the illness. A phylogenetic tree revealed that the DENV-2 isolates belonged to a new clade of cosmopolitan genotype and were genetically close to strains identified in China, South Korea, Singapore, Malaysia, Thailand, and the Philippines. According to the NGS analysis, greater frequencies of nonsynonymous and synonymous mutations per gene were identified in the nonstructural genes. The full genomes of serum- and CSF-derived DENV-2 from the same patient shared 99.7% similarity, indicating that the virus spread across the blood-brain barrier. This is the first report to describe neurotropic DENV-2 using whole-genome analysis and to provide the clinical, immunological, and virological characteristics of dengue encephalitis patients during a severe dengue outbreak in Sri Lanka in 2017., PLOS ONE, 15(6), art.no.e0234508; 2020

The Lyhamyar deposit is a large Sb deposit in the Southern Shan Plateau, Eastern Myanmar. The deposit is located in the Early Silurian Linwe Formation, occurring as syntectonic quartz-stibnite veins. The ore body forms an irregular staircase shape, probably related to steep faulting. Based on the mineral assemblages and cross-cutting relationships, the deposit shows two mineralization stages: (1) the pre-ore sedimentary and diagenetic stage, and (2) the main-ore hydrothermal ore-forming stage (including stages I, II, and III), i.e., (i) early-ore stage (stage I) Quartz-Stibnite, (ii) late-ore stage (stage II) Quartz-calcite-Stibnite &plusmn, Pyrite, and (iii) post-ore stage (stage III) carbonate. The ore-forming fluid homogenization temperatures from the study of primary fluid inclusions in quartz and calcite indicate that the ore-forming fluid was of a low temperature (143.8&ndash, 260.4 &deg, C) and moderate to high-salinity (2.9&ndash, 20.9 wt. % NaCl equivalent). Hydrogen and oxygen isotopes suggest that the ore-forming fluids of the Lyhamyar deposit were derived from circulating meteoric water mixed with magmatic fluids that underwent isotopic exchange with the surrounding rocks. Sulfur in Lyhamyar was dominated by thermochemical sulfate reduction (TSR) with dominant magmatic source sulfur. The lead isotope compositions of the stibnite indicate that the lead from the ore-forming metals was from the upper crustal lead reservoir and orogenic lead reservoir. On the basis of the integrated geological setting, ore geology, fluid inclusions, (H-O-S-Pb) isotope data, and previous literature, we propose a new ore-deposit model for the Lyhamyar Sb deposit: It was involved in an early deposition of pyrite in sedimentary and diagenetic stages and later Sb mineralization by mixing of circulating meteoric water with ascending magmatic fluids during the hydrothermal mineralization stage.

Dyslipidaemia and increased oxidative stress have been reported in severe obstructive sleep apnea, and both may be related to the development of cardiovascular disease. We have previously shown in a randomized crossover study in patients with moderate to severe obstructive sleep apnea that therapeutic continuous positive airway pressure treatment for 8 weeks improved postprandial triglycerides and total cholesterol when compared with sham continuous positive airway pressure. From this study we have now compared the effect of 8 weeks of therapeutic continuous positive airway pressure and sham continuous positive airway pressure on oxidative lipid damage and plasma lipophilic antioxidant levels. Unesterified cholesterol, esterified unsaturated fatty acids (cholesteryl linoleate: C18:2; and cholesteryl arachidonate: C20:4; the major unsaturated and oxidizable lipids in low-density lipoproteins), their corresponding oxidized products [cholesteryl ester-derived lipid hydroperoxides and hydroxides (CE-O(O)H)] and antioxidant vitamin E were assessed at 20:30 hours before sleep, and at 06:00 and 08:30 hours after sleep. Amongst the 29 patients completing the study, three had incomplete or missing [CE-O(O)H] data. The mean apnea -hypopnoea index, age and body mass index were 38 per hour, 49 years and 32 kg m(-2) , respectively. No differences in lipid-based oxidative markers or lipophilic antioxidant levels were observed between the continuous positive airway pressure and sham continuous positive airway pressure arms at any of the three time-points [unesterified cholesterol 0.01 mm, P > 0.05; cholesteryl linoleate: C18:2 0.05 mm, P > 0.05; cholesteryl arachidonate: C20:4 0.02 mm, P = 0.05; CE-O(O)H 2.5 nm, P > 0.05; and lipid-soluble antioxidant vitamin E 0.03 μm, P > 0.05]. In this study, accumulating CE-O(O)H, a marker of lipid oxidation, does not appear to play a role in oxidative stress in obstructive sleep apnea. National Health and Medical Research Council project grant 301936