Low-dose hydrocortisone prolongs survival in a lethal sepsis model in adrenalectomized rats

2018 ◽  
Vol 227 ◽  
pp. 72-80 ◽  
Author(s):  
Triantafyllos Doulias ◽  
Stefanie Quickert ◽  
Sebastien Weis ◽  
Ralf A. Claus ◽  
Konstantina Kontopoulou ◽  
...  
Keyword(s):  
Low Dose ◽  
Sepsis Model ◽  
Lethal Sepsis ◽  
Adrenalectomized Rats

Histone Deacetylase Inhibitor SAHA Attenuates Coagulation Imbalance in a Lethal Sepsis Model

2014 ◽  
Vol 186 (2) ◽  
pp. 583
Author(s):  
T. Zhao ◽  
Y. Li ◽  
B. Liu ◽  
E. Wu ◽  
M. Sillesen ◽  
...  
Keyword(s):  
Histone Deacetylase ◽  
Histone Deacetylase Inhibitor ◽  
Sepsis Model ◽  
Deacetylase Inhibitor ◽  
Lethal Sepsis

scholarly journals Protective Role of an Initial Low-Dose Septic Challenge against Lethal Sepsis in Neonatal Mice: A Pilot Study

2021 ◽  
Vol 10 (24) ◽  
pp. 5823
Author(s):  
Ruka Nakasone ◽  
Mariko Ashina ◽  
Takumi Kido ◽  
Harunori Miyauchi ◽  
Masafumi Saito ◽  
...  
Keyword(s):  
Neonatal Sepsis ◽  
Therapeutic Strategy ◽  
Low Dose ◽  
Inflammatory Responses ◽  
Lethal Dose ◽  
Protective Role ◽  
Bacterial Invasion ◽  
Initial Exposure ◽  
Lethal Sepsis

Neonatal sepsis is characterized by systemic bacterial invasion followed by a massive inflammatory response. At present, no therapeutic strategy has been found that significantly reduces the mortality of neonatal sepsis. We aimed to investigate the protective role of an initial low-dose septic challenge for the prevention of subsequent lethal sepsis in a mouse model. A stock cecal slurry (CS) solution was prepared from adult ceca. The LD83 (1.5 mg CS/g) was used for all animals. An initial challenge of normal saline (NS) or 0.5 mg CS/g (non-lethal dose) was administered at four days of age, then 1.5 mg CS/g was administered intraperitoneally at seven days of age (72 h post-initial challenge), and survival was monitored. Initial exposure to NS (n = 10) resulted in 90% mortality following exposure to the LD83 CS dose in contrast to an initial exposure to CS (n = 16), which significantly decreased mortality to 6% (p < 0.0001), reduced blood bacterial counts, attenuated inflammatory responses, and suppressed lipid mediators. Initial exposure to a non-lethal CS dose prior to exposure to a lethal CS dose significantly reduces sepsis mortality, a protective effect that might be mediated by modulating abnormal systemic inflammatory responses.

THE EFFECT OF ALDOSTERONE ON THE ELECTRICAL ACTIVITY OF RAT COLON

1969 ◽  
Vol 44 (3) ◽  
pp. 363-377 ◽  
Author(s):  
C. J. EDMONDS ◽  
JANE C. MARRIOTT
Keyword(s):  
Large Dose ◽  
Low Dose ◽  
Dose Range ◽  
Rat Colon ◽  
Low Doses ◽  
Continuous Intravenous Infusion ◽  
Submucosal Injection ◽  
High Doses ◽  
Conscious Animals ◽  
Adrenalectomized Rats

SUMMARY The effect of aldosterone on the colonic transmucosal potential difference (p.d.) was examined in normal, adrenalectomized and Na+ depleted rats. Continuous intravenous infusion of aldosterone in conscious animals was more effective than single i.v. injection and over the dose range 0·5–50 μg./hr. for 6 hr., p.d. increased linearly with log dose and returned to the pre-infusion levels 16–24 hr. after stopping infusion. Only a region 2–4 cm. from the anus responded to low doses, but with high doses an increasing length of colon responded. Cortisone (250 μg. daily) intramuscularly maintained adrenalectomized rats even when severely Na+ depleted without affecting the p.d. Cortisone (2·5 mg. daily, i.m.) raised the p.d. but the effect of low doses of aldosterone was unchanged. Neither Na+ depletion nor pentobarbitone anaesthesia affected the action of aldosterone but large doses of spironolactone reduced it. Aldosterone was effective when applied locally by submucosal injection in very low dose but was almost ineffective even in very large dose in the lumen. Again the most sensitive region was 2–4 cm. from the anus. Ouabain (10-3m) injected into the submucosa rapidly reduced the increased p.d. but was ineffective in the lumen.

Ovarian Dysfunction in Fetally Irradiated Beagles

1977 ◽  
Vol 35 ◽  
pp. 658-659
Author(s):  
T. M. Seed ◽  
M. H. Sanderson ◽  
D. L. Gutzeit ◽  
T. E. Fritz ◽  
D. V. Tolle ◽  
...  
Keyword(s):  
Gamma Rays ◽  
Low Dose ◽  
Long Term Effects ◽  
Ovarian Dysfunction ◽  
Dose Rates ◽  
Highly Sensitive ◽  
Microscopic Evaluation ◽  
Ovarian Pathology ◽  
Normal Offspring

The developing mammalian fetus is thought to be highly sensitive to ionizing radiation. However, dose, dose-rate relationships are not well established, especially the long term effects of protracted, low-dose exposure. A previous report (1) has indicated that bred beagle bitches exposed to daily doses of 5 to 35 R 60Co gamma rays throughout gestation can produce viable, seemingly normal offspring. Puppies irradiated in utero are distinguishable from controls only by their smaller size, dental abnormalities, and, in adulthood, by their inability to bear young.We report here our preliminary microscopic evaluation of ovarian pathology in young pups continuously irradiated throughout gestation at daily (22 h/day) dose rates of either 0.4, 1.0, 2.5, or 5.0 R/day of gamma rays from an attenuated 60Co source. Pups from non-irradiated bitches served as controls. Experimental animals were evaluated clinically and hematologically (control + 5.0 R/day pups) at regular intervals.

High Resolution Microscopy of Multi-Layered Biological Crystals

1982 ◽  
Vol 40 ◽  
pp. 80-83
Author(s):  
H.A. Cohen ◽  
T.W. Jeng ◽  
W. Chiu
Keyword(s):  
High Resolution ◽  
Low Dose ◽  
Three Dimensional ◽  
Data Interpretation ◽  
Two Dimensional ◽  
Biological Objects ◽  
Density Maps ◽  
Density Map ◽  
Complex Crystal ◽  
High Resolution Microscopy

This tutorial will discuss the methodology of low dose electron diffraction and imaging of crystalline biological objects, the problems of data interpretation for two-dimensional projected density maps of glucose embedded protein crystals, the factors to be considered in combining tilt data from three-dimensional crystals, and finally, the prospects of achieving a high resolution three-dimensional density map of a biological crystal. This methodology will be illustrated using two proteins under investigation in our laboratory, the T4 DNA helix destabilizing protein gp32*I and the crotoxin complex crystal.

Characterization of microtubules by dark-field STEM and replication

1991 ◽  
Vol 49 ◽  
pp. 152-153
Author(s):  
S.B. Andrews ◽  
R.D. Leapman ◽  
P.E. Gallant ◽  
T.S. Reese
Keyword(s):  
Protein Interactions ◽  
Low Dose ◽  
Unit Length ◽  
Dark Field ◽  
Carbon Films ◽  
Microtubule Associated Proteins ◽  
Molecular Weights ◽  
Freeze Dried ◽  
Protein Motors ◽  
Associated Proteins

As part of a study on protein interactions involved in microtubule (MT)-based transport, we used the VG HB501 field-emission STEM to obtain low-dose dark-field mass maps of isolated, taxol-stabilized MTs and correlated these micrographs with detailed stereo images from replicas of the same MTs. This approach promises to be useful for determining how protein motors interact with MTs. MTs prepared from bovine and squid brain tubulin were purified and free from microtubule-associated proteins (MAPs). These MTs (0.1-1 mg/ml tubulin) were adsorbed to 3-nm evaporated carbon films supported over Formvar nets on 600-m copper grids. Following adsorption, the grids were washed twice in buffer and then in either distilled water or in isotonic or hypotonic ammonium acetate, blotted, and plunge-frozen in ethane/propane cryogen (ca. -185 C). After cryotransfer into the STEM, specimens were freeze-dried and recooled to ca.-160 C for low-dose (<3000 e/nm2) dark-field mapping. The molecular weights per unit length of MT were determined relative to tobacco mosaic virus standards from elastic scattering intensities. Parallel grids were freeze-dried and rotary shadowed with Pt/C at 14°.

Structural analysis of the surface-layer protein of spirillum serpens by high-resolution electron microscopy

1983 ◽  
Vol 41 ◽  
pp. 738-739
Author(s):  
W. H. Wu ◽  
R. M. Glaeser
Keyword(s):  
Electron Microscopy ◽  
Surface Layer ◽  
Structural Analysis ◽  
High Resolution ◽  
Low Dose ◽  
High Resolution Electron Microscopy ◽  
Optical Diffraction ◽  
Surface Layer Protein ◽  
Morphological Unit ◽  
Resolution Electron

Spirillum serpens possesses a surface layer protein which exhibits a regular hexagonal packing of the morphological subunits. A morphological model of the structure of the protein has been proposed at a resolution of about 25 Å, in which the morphological unit might be described as having the appearance of a flared-out, hollow cylinder with six ÅspokesÅ at the flared end. In order to understand the detailed association of the macromolecules, it is necessary to do a high resolution structural analysis. Large, single layered arrays of the surface layer protein have been obtained for this purpose by means of extensive heating in high CaCl2, a procedure derived from that of Buckmire and Murray. Low dose, low temperature electron microscopy has been applied to the large arrays.As a first step, the samples were negatively stained with neutralized phosphotungstic acid, and the specimens were imaged at 40,000 magnification by use of a high resolution cold stage on a JE0L 100B. Low dose images were recorded with exposures of 7-9 electrons/Å2. The micrographs obtained (Fig. 1) were examined by use of optical diffraction (Fig. 2) to tell what areas were especially well ordered.

Distribution of newly formed hepatic glycogen in adrenalectomized rats as observed by radioautography after injection of 3H-galactose

1984 ◽  
Vol 42 ◽  
pp. 228-229
Author(s):  
J. E. Michaels ◽  
J. T. Hung ◽  
E. L. Cardell ◽  
R. R. Cardell
Keyword(s):  
Glycogen Synthesis ◽  
Hepatic Glycogen ◽  
Electron Microscopic ◽  
Routine Procedures ◽  
Silver Grains ◽  
Synthetic Glucocorticoid ◽  
Adrenalectomized Rats

In order to study early events of glycogen synthesis, we have used adrenalectomized (ADX) rats fasted overnight and injected with the synthetic glucocorticoid dexamethasone (DEX) to stimulate glycogen synthesis. Rats were given DEX 0-5 hr prior to sacrifice and injected with 2 mCi 3H-galactose 1 hr prior to sacrifice. Liver was prepared for light (LM) and electron microscopic (EM) radioautography by routine procedures.The concentration of silver grains over hepatic cytoplasm was measured in LM radioautographs using a Zeiss Videoplan. The hepatocytes were categorized as unlabeled if no silver grains (gr) were present, lightly labeled (<10gr/100 μm2 cytoplasm) or intensely labeled (>10 gr/1002 μm cytoplasm). Although very few hepatocytes showed heavy labeling after 1 hr treatment with DEX, by 2 hr after DEX treatment 8% of the cells distributed throughout the lobule were intensely labeled.

The Response of Testis Cells to Low Dose X-Irradiation

1981 ◽  
Vol 39 ◽  
pp. 542-543
Author(s):  
D. E. Philpott ◽  
W. Sapp ◽  
C. Williams ◽  
Joann Stevenson ◽  
S. Black
Keyword(s):  
Electron Microscopy ◽  
Stem Cell ◽  
Light Microscopy ◽  
Dose Level ◽  
Cross Sections ◽  
Low Dose ◽  
Light And Electron Microscopy ◽  
Cellular Responses ◽  
Post Irradiation ◽  
X Irradiation

The response of spermatogonial cells to X-irradiation is well documented. It has been shown that there is a radiation resistent stem cell (As) which, after irradiation, replenishes the seminiferous epithelium. Most investigations in this area have dealt with radiation dosages of 100R or more. This study was undertaken to observe cellular responses at doses less than 100R of X-irradiation utilizing a system in which the tissue can be used for light and electron microscopy.Brown B6D2F1 mice aged 16 weeks were exposed to X-irradiation (225KeV; 15mA; filter 0.35 Cu; 50-60 R/min). Four mice were irradiated at each dose level between 1 and 100 rads. Testes were removed 3 days post-irradiation, fixed, and embedded. Sections were cut at 2 microns for light microscopy. After staining, surviving spermatogonia were identified and counted in tubule cross sections. The surviving fraction of spermatogonia compared to control, S/S0, was plotted against dose to give the curve shown in Fig. 1.

Search mode for rapid detection of virus particles

1991 ◽  
Vol 49 ◽  
pp. 286-287
Author(s):  
O. E. Bradfute
Keyword(s):  
Electron Microscopy ◽  
Rapid Detection ◽  
Plant Virus ◽  
Low Dose ◽  
Search Mode ◽  
Virus Diseases ◽  
Virus Particles ◽  
Focus Image ◽  
Time Required ◽  
Rapid Switching

Electron microscopy is frequently used in preliminary diagnosis of plant virus diseases by surveying negatively stained preparations of crude extracts of leaf samples. A major limitation of this method is the time required to survey grids when the concentration of virus particles (VPs) is low. A rapid survey of grids for VPs is reported here; the method employs a low magnification, out-of-focus Search Mode similar to that used for low dose electron microscopy of radiation sensitive specimens. A higher magnification, in-focus Confirm Mode is used to photograph or confirm the detection of VPs. Setting up the Search Mode by obtaining an out-of-focus image of the specimen in diffraction (K. H. Downing and W. Chiu, private communications) and pre-aligning the image in Search Mode with the image in Confirm Mode facilitates rapid switching between Modes.

Sign in / Sign up

Export Citation Format

Share Document