Effects of gelatin-based antifreeze peptides on cell viability and oxidant stress of Streptococcus thermophilus during cold stage

2020 ◽  
Vol 136 ◽  
pp. 111056 ◽  
Author(s):  
Xu Chen ◽  
Ling Li ◽  
Fujia Yang ◽  
Jinhong Wu ◽  
Shaoyun Wang
Keyword(s):  
Cell Viability ◽  
Oxidant Stress ◽  
Streptococcus Thermophilus ◽  
Cold Stage ◽  
Antifreeze Peptides

Antisense oligodeoxynucleotides to inducible NO synthase rescue epithelial cells from oxidative stress injury

1996 ◽  
Vol 270 (6) ◽  
pp. F971-F977 ◽  
Author(s):  
T. Peresleni ◽  
E. Noiri ◽  
W. F. Bahou ◽  
M. S. Goligorsky
Keyword(s):  
Epithelial Cells ◽  
Cell Viability ◽  
Cell Damage ◽  
Oxidant Stress ◽  
Selective Inhibition ◽  
Stress Injury ◽  
Cytoplasmic Staining ◽  
Nitrite Production ◽  
Stressed Cells ◽  
Antisense Odns

Until recently, the lack of specific inhibitors of various forms of nitric oxide synthase (NOS) hampered a stringent evaluation of the role played by inducible NOS (iNOS) in cell damage. Phosphorothioate derivatives of iNOS antisense and control sense or scrambled oligodeoxynucleotides (S-ODNs) were synthesized, and their effect on epithelial cell viability was examined under oxidant stress. Exposure of BSC-1 kidney tubular epithelial cells to H2O2 resulted in elevation of NO release, accompanied by a significant decrease in the population of viable cells (from 97.4 +/- 1.7% to 72.4 +/- 2.4% population). Nitrite production by BSC-1 cells exposed to H2O2 increased almost 10-fold compared with control. Pretreatment of the cells with 10 microM antisense ODNs significantly blunted this response, whereas sense or scrambled ODNs did not modify it. Pretreatment of BSC-1 cells with 10 microM antisense ODNs virtually prevented lethal cell damage in response to H2O2, whereas sense ODNs were ineffective. Lipopolysaccharide induction of iNOS, also preventable by the antisense construct, resulted in a lesser compromise to cell viability. Immunocytochemistry of iNOS in cells pretreated with antisense ODNs showed minimal cytoplasmic staining, as opposed to the untreated or sense ODN-treated positively stained cells. Staining with antibodies to nitrotyrosine was conspicuous in stressed cells but undetectable in antisense ODN-treated cells. In conclusion, oxidant stress is accompanied by the induction of iNOS, increased production of NO, and impaired cell viability; selective inhibition of iNOS using the designed antisense ODNs dramatically improved BSC-1 cell viability after oxidant stress.

scholarly journals Hydrogen peroxide effects on Streptococcus thermophilus CNRZ368 cell viability

2001 ◽  
Vol 152 (6) ◽  
pp. 593-596 ◽  
Author(s):  
Annabelle Thibessard ◽  
Annabelle Fernandez ◽  
Brigitte Gintz ◽  
Nathalie Leblond-Bourget ◽  
Bernard Decaris
Keyword(s):  
Hydrogen Peroxide ◽  
Cell Viability ◽  
Streptococcus Thermophilus

scholarly journals The Human Transient Receptor Potential Melastatin 2 Ion Channel Modulates ROS Through Nrf2

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Lei Bao ◽  
Fernanda Festa ◽  
Christopher S. Freet ◽  
John P. Lee ◽  
Iwona M. Hirschler-Laszkiewicz ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Cell Viability ◽  
Transient Receptor Potential ◽  
Oxidant Stress ◽  
Receptor Potential ◽  
Related Factor ◽  
Wild Type ◽  
Transient Receptor Potential Melastatin ◽  
Transient Receptor ◽  
Nadh Generation

Abstract Transient receptor potential melastatin channel subfamily member 2 (TRPM2) has an essential role in protecting cell viability through modulation of oxidative stress. TRPM2 is highly expressed in cancer. When TRPM2 is inhibited, mitochondria are dysfunctional, ROS levels are increased, and cell viability is reduced. Here, the importance of NF-E2-related factor (Nrf2) in TRPM2-mediated suppression of oxidant stress was explored. In TRPM2 depleted cells, antioxidant cofactors glutathione, NADPH, and NADH were significantly reduced. Cytoplasmic and nuclear expression of Nrf2 and of IQGAP1, a modulator of Nrf2 stability regulated by intracellular calcium, were decreased. Antioxidant enzymes transcriptionally regulated by Nrf2 and involved in GSH, NADPH, and NADH generation were significantly lower including PRX1 and PRX3, GPX4, GSTP1, GCLC, and MTHFD2. The glutamine pathway leading to GSH production was suppressed, and ATP and GTP levels were impaired. Reconstitution with wild type TRPM2 or Nrf2, but not TRPM2 pore mutant E960D, rescued expression of enzymes downstream of Nrf2 and restored GSH and GTP. Cell viability, ROS, NADPH, NADH, and ATP levels were fully rescued by TRPM2 and partially by Nrf2. These data show that TRPM2 maintains cell survival following oxidative stress through modulation of antioxidant pathways and cofactors regulated by Nrf2.

Extended Preservation of Iron for Transmission

1967 ◽  
Vol 25 ◽  
pp. 354-355
Author(s):  
E. P. Abrahamson II ◽  
M. W. Dumais
Keyword(s):  
Acid Solution ◽  
Perchloric Acid ◽  
Microscopy Study ◽  
Perchloric Acid Solution ◽  
Transmission Microscopy ◽  
Iron Base ◽  
Cold Stage

In a transmission microscopy study of iron and dilute iron base alloys, it was determined that it is possible to preserve specimens for extended periods of time. Our specimens were prepunched from 5 to 8 mil sheet to microscope size and annealed for several hours at 700°C. They were then thinned in a glacial acetic-12 percent perchloric acid solution using 10 volts and 20 milliamperes, at a temperature of 8 to 14°C.It was noted that by the use of a cold stage, the same specimen can be observed for periods up to one week without excess contamination. When removal of the specimen from the column becomes necessary, it was observed that a specimen may be kept for later observation in 1,2 dichloroethene or methanol for periods in excess of two weeks.

SEM Cold Stage Techniques for the Observation of Vegetative and Floral Apices of Oat (Avena sativa L.) Plants

1977 ◽  
Vol 35 ◽  
pp. 590-591
Author(s):  
B. K. Kirchoff ◽  
L.F. Allard ◽  
W.C. Bigelow
Keyword(s):  
Critical Point ◽  
Avena Sativa ◽  
Substantial Improvement ◽  
Fresh Tissue ◽  
Cold Stage ◽  
Critical Point Drying ◽  
Almost All ◽  
Cell Collapse ◽  
Conductive Paint ◽  
Carbon Based

In attempting to use the SEM to investigate the transition from the vegetative to the floral state in oat (Avena sativa L.) it was discovered that the procedures of fixation and critical point drying (CPD), and fresh tissue examination of the specimens gave unsatisfactory results. In most cases, by using these techniques, cells of the tissue were collapsed or otherwise visibly distorted. Figure 1 shows the results of fixation with 4.5% formaldehyde-gluteraldehyde followed by CPD. Almost all cellular detail has been obscured by the resulting shrinkage distortions. The larger cracks seen on the left of the picture may be due to dissection damage, rather than CPD. The results of observation of fresh tissue are seen in Fig. 2. Although there is a substantial improvement over CPD, some cell collapse still occurs.Due to these difficulties, it was decided to experiment with cold stage techniques. The specimens to be observed were dissected out and attached to the sample stub using a carbon based conductive paint in acetone.

A High Angle, Double Tilting Cold Stage for the AEI EM7

1974 ◽  
Vol 32 ◽  
pp. 450-451
Author(s):  
P.R. Swann ◽  
A.E. Lloyd
Keyword(s):  
Habit Plane ◽  
Temperature Control ◽  
Tilt Angle ◽  
Cooling System ◽  
Thermal Drift ◽  
High Angle ◽  
Cold Stage ◽  
High Degree ◽  
Better Than

Figure 1 shows the design of a specimen stage used for the in situ observation of phase transformations in the temperature range between ambient and −160°C. The design has the following features a high degree of specimen stability during tilting linear tilt actuation about two orthogonal axes for accurate control of tilt angle read-out high angle tilt range for stereo work and habit plane determination simple, robust construction temperature control of better than ±0.5°C minimum thermal drift and transmission of vibration from the cooling system.

SEM evaluation of the TEM cold-stage double-film specimen

1984 ◽  
Vol 42 ◽  
pp. 272-273
Author(s):  
Jayesh Bellare
Keyword(s):  
Spatial Distribution ◽  
Sample Preparation ◽  
Sample Thickness ◽  
Specimen Preparation ◽  
Preparation Technique ◽  
Liquid Sample ◽  
Thin Specimen ◽  
Sample Preparation Technique ◽  
Cold Stage ◽  
Film Specimen

Seeing is believing, but only after the sample preparation technique has received a systematic study and a full record is made of the treatment the sample gets.For microstructured liquids and suspensions, fast-freeze thermal fixation and cold-stage microscopy is perhaps the least artifact-laden technique. In the double-film specimen preparation technique, a layer of liquid sample is trapped between 100- and 400-mesh polymer (polyimide, PI) coated grids. Blotting against filter paper drains excess liquid and provides a thin specimen, which is fast-frozen by plunging into liquid nitrogen. This frozen sandwich (Fig. 1) is mounted in a cooling holder and viewed in TEM.Though extremely promising for visualization of liquid microstructures, this double-film technique suffers from a) ireproducibility and nonuniformity of sample thickness, b) low yield of imageable grid squares and c) nonuniform spatial distribution of particulates, which results in fewer being imaged.

Electron Microscopic Observation of Biological Specimens in Their Native State by Employing Cryogenic Techniques

1972 ◽  
Vol 30 ◽  
pp. 410-411 ◽  
Author(s):  
Tokio Nei ◽  
Haruo Yotsumoto ◽  
Yoichi Hasegawa ◽  
Yuji Nagasawa
Keyword(s):  
Electron Microscopic Observation ◽  
Surface Structures ◽  
Specimen Preparation ◽  
Native State ◽  
Electron Microscopic ◽  
Biological Specimen ◽  
Specimen Holder ◽  
Cold Stage ◽  
Preparation Techniques ◽  
Scanning Electron

In order to observe biological specimens in their native state, that is, still containing their water content, various methods of specimen preparation have been used, the principal two of which are the chamber method and the freeze method.Using its recently developed cold stage for installation in the pre-evacuation chamber of a scanning electron microscope, we have succeeded in directly observing a biological specimen in its frozen state without the need for such conventional specimen preparation techniques as drying and metallic vacuum evaporation. (Echlin, too, has reported on the observation of surface structures using the same freeze method.)In the experiment referred to herein, a small sliced specimen was place in the specimen holder. After it was rapidly frozen by freon cooled with liquid nitrogen, it was inserted into the cold stage of the specimen chamber.

Water accumulation as a function of temperature on specimens in an electron microscope cold stage

1986 ◽  
Vol 44 ◽  
pp. 114-115 ◽  
Author(s):  
M.K. Lamvik ◽  
D.A. Kopf ◽  
S.D. Davilla ◽  
J.D. Robertson
Keyword(s):  
Electron Microscope ◽  
Mass Loss ◽  
Liquid Helium ◽  
Liquid Nitrogen ◽  
Liquid Nitrogen Temperature ◽  
Liquid Helium Temperature ◽  
Helium Temperature ◽  
Cold Stage ◽  
Water Accumulation ◽  
Better Than

Last year we reported1 that there is a striking reduction in the rate of mass loss when a specimen is observed at liquid helium temperature. It is important to determine whether liquid helium temperature is significantly better than liquid nitrogen temperature. This requires a good understanding of mass loss effects in cold stages around 100K.

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