The effect of lethal doses of radiation in vivo on the lipid microviscosity of tumor nuclear membranes

1996 ◽  
Vol 47 (11-12) ◽  
pp. 1683-1687 ◽  
Author(s):  
E.L. Mal'Tseva ◽  
N.P. Pal'Mina
1918 ◽  
Vol 28 (5) ◽  
pp. 571-583
Author(s):  
Julia T. Parker

1. The livers of rabbits inoculated with cultures of Bacillus typhosus or Bacillus prodigiosus under certain conditions contain a toxic substance extractable with salt solution. When the toxic extracts are injected intravenously into normal rabbits the latter animals develop symptoms resembling those of anaphylactic shock and succumb. The lethal doses of the toxic extracts are far smaller than those of normal liver extract. 2. The livers of rabbits injected with typhoid antigen also yield a toxic extract. 3. Boiling as well as filtration through a Berkefeld filter only partially detoxicates the extract. 4. Tolerance to one to two lethal doses of the poisonous extracts can be induced by cautious immunization. 5. Rabbits actively immunized to Bacillus typhosus or Bacillus prodigiosus usually resist one lethal dose of the homologous liver poison; and animals tolerant to the typhoid liver poison resist one minimum lethal dose at least of Bacillus typhosus. 6. Typhoid immune serum is not detoxicating either in vivo or in vitro for the typhoid liver poison. 7. The liver poisons are specific, since rabbits actively immunized to either Bacillus typhosus or Bacillus prodigiosus withstand at least one minimum lethal dose of the homologous but not of the heterologous-liver poisons.


1961 ◽  
Vol 201 (1) ◽  
pp. 16-18 ◽  
Author(s):  
J. Cascarano ◽  
A. D. Rubin ◽  
A. K. Neumann ◽  
B. W. Zweifach

The in vivo inhibition of liver and kidney succinic dehydrogenase by administration of lethal doses of bacterial endotoxin ( Escherichia coli and Salmonella typhosa) was investigated. Quantitative determinations conducted on tissue homogenates revealed significant inhibition of activity only in liver of rabbits injected with E. coli lipopolysaccharide. The histochemical distribution of succinic dehydrogenase in fresh frozen sections of kidney was the same in both control and experimental animals. However, the centrolobular areas of liver appeared considerably depressed in activity in both E. coli and S. typhosa endotoxin-treated animals. These data, along with those presented by other studies in the literature, suggest that the action of endotoxin appears to be restricted to certain cells.


1996 ◽  
Vol 16 (10) ◽  
pp. 5857-5864 ◽  
Author(s):  
J Han ◽  
P Sabbatini ◽  
E White

The E1B 19-kilodalton protein (19K protein) is a potent apoptosis inhibitor and the adenovirus homolog of Bcl-2 (E. White, Genes Dev. 10:1-15, 1996). To obtain a better understanding of the biochemical mechanism by which the E1B 19K protein regulates apoptosis, proteins that interact with 19K have been identified; one of these is Bax (J. Han, P. Sabbatini, D. Perez, L. Rao, D. Mohda, and E. White, Genes Dev. 10:461-477, 1996), and another is Bak (S. N. Farrow, J. H. M. White, I. Martinou, T. Raven, K.-T. Pun, C. J. Grinham, J.-C. Martinou, and R. Brown, Nature (London) 374:731-733, 1995). Bax and Bak are Bcl-2 family members which contain Bcl-2 homology regions 1, 2, and 3 (BH1, BH2, and BH3), which interact with E1B 19K and Bcl-2 and promote apoptosis. Like Bax and Bak, Nbk was cloned from a yeast two-hybrid screen for proteins that interact with E1B 19K. Nbk contained BH3 but not BH1 or BH2. It also interacted with Bcl-2 but not with Bax. Both Bcl-2 and E1B 19K interacted with Nbk in vitro, and this interaction was highly specific. In vivo, the Nbk and E1B 19K proteins may colocalize with cytoplasmic and nuclear membranes. Nbk expression functionally antagonized 19K-mediated inhibition of apoptotic cell death and completely prevented transformation by E1A and E1B 19K. Nbk was sufficient for induction of apoptosis in the presence of mutant p53 and thus low levels of Bax, suggesting that Nbk functions independently of Bax to induce apoptosis. Nbk may therefore represent a novel death regulator which contains only a BH3 that interacts with and antagonizes apoptosis inhibitors such as the E1B 19K protein.


2016 ◽  
Vol 36 (1) ◽  
pp. 23-32 ◽  
Author(s):  
Devyani Swami ◽  
Hitendra N Karade ◽  
Jyotiranjan Acharya ◽  
Pravin Kumar

In vivo antidotal efficacy of new bis- quaternary 2-(hydroxyimino)- N-(pyridin-3yl) acetamide derivatives (HNK series), to counter multiples of lethal doses of nerve agent sarin (GB) and reactivation of acetylcholinesterase (AChE), was evaluated in Swiss albino mice. [Protection index PI; median lethal dose (LD50) of sarin with treatment/LD50 of sarin] was estimated, using 0.05, 0.10, and 0.20 LD50 as treatment doses of all the oximes with atropine against sarin poisoning. Dose-dependent time course study was conducted at 0.2, 0.4 and 0.8 LD50 dose of sarin for estimating maximum AChE inhibition. At optimized time (15 min), in vivo enzyme half inhibition concentration (IC50) was calculated. AChE reactivation efficacy of HNK series and pralidoxime (2-PAM) were determined by plotting shift of log IC50 doses. HNK-102 with atropine showed three fold higher PI compared to 2-PAM. In vivo IC50 of sarin for brain and serum AChE was found to be 0.87 LD50 (139.2 µg/kg) and 0.48 LD50 (77.23 µg/kg), respectively. Treatment with HNK-102 and HNK-111 (equal to their 0.20LD50) significantly reactivated sarin-intoxicated AChE ( p < 0.05) at 2× IC50 dose of sarin, compared to 2-PAM. The study revealed that HNK-102 oxime was three times more potent as antidote, for acute sarin poisoning compared to 2-PAM in vivo.


2003 ◽  
Vol 38 (3) ◽  
pp. 342-358 ◽  
Author(s):  
Jianzhong Sun ◽  
James R. Fuxa ◽  
Gregg Henderson

Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae) was used as “bait” to isolate pathogenic fungi from soil. Ninety soil samples were collected from woodlands and pastures in the vicinities of Baton Rouge, New Orleans, and Lake Charles, LA, from which six Metarhizium anisopliae (Metsch.) Sorokin and nine Beauveria bassiana (Balsamo) Vuillemin isolates were obtained. Numbers of fungal isolates from the three sampling locations did not differ, but more isolates were found in woodlands than in pastures. Median lethal doses (LD50s) of these fungal species to C. formosanus were interspersed, indicating that fungal isolates rather than species had the greatest effect on virulence. Among nine Louisiana and two USDA isolates of B. bassiana, LD50s ranged from 4.95 × 103 to 4.96 × 105 conidia/termite, a difference of 100×. LD50s of six Louisiana and four USDA isolates of M. anisopliae ranged from 7.89 × 103 to 1.22 × 105 conidia/termite. Survival time also was used to compare virulence; M. anisopliae infections caused significantly shorter host survival times than B. bassiana. In vitro growth characteristics were significantly correlated with virulence against termites, suggesting that the characteristics of a fungus growing on agar might contribute to estimating the fungal virulence in vivo.


1998 ◽  
Vol 17 (11) ◽  
pp. 620-624 ◽  
Author(s):  
R Ennamany ◽  
A Bingen ◽  
E E Creppy ◽  
O Kretz ◽  
J P Gut ◽  
...  

Bolesatine is a toxic glycoprotein isolated from Boletus satanas Lenz, which inhibits protein synthesis in vivo and in vitro. The LD50 (24 h) is 1 mg /kg bw (i.p.), in mice and rats. When given i.p. to mice (0.1 - 1.0 mg/kg bw) bolesatine induced thrombi and blood stasis in the liver, 5 - 21 h after injection, and modifications of the number of blood corpuscles in peripheral blood. These effects were efficiently reversed by aspirin, ticlopidin and heparin (as attested by histology and electron microscopy) which however failed to prevent death in animals given lethal doses. Together, these results showed that the death of bolesatine poisoned animals given high doses, was rather due to a combination of thrombosis and other toxic effects. In addition, they suggest that these antithrombotic drugs may overcome cases of human poisoning, with low exposures of this boletus, showing a hypertension probably due to mechanical obstruction which resists normal therapy.


2008 ◽  
Vol 15 (5) ◽  
pp. 737-743 ◽  
Author(s):  
Kalpana Surendranath ◽  
Anjali A. Karande

ABSTRACT Plant ribosome-inactivating proteins (RIPs) are RNA N-glycosidases that inhibit protein synthesis in cells. Abrin, a type II RIP, is an AB type toxin, which is one of the most lethal types of toxin known. The B chain facilitates the entry of the molecule into the cell, whereas the A chain exerts the toxic effect. We have generated hybridomas secreting antibodies of the immunoglobulin G class specific to the recombinant A chain of abrin. One monoclonal antibody, namely, D6F10, rescued cells from abrin toxicity. Importantly, the antibody also protected mice from lethal doses of the toxin. The neutralizing effect of the antibody was shown to be due to interference with abrin attachment to the cell surface.


2013 ◽  
Vol 203 (2) ◽  
pp. 205-213 ◽  
Author(s):  
Sarah Oddoux ◽  
Kristien J. Zaal ◽  
Victoria Tate ◽  
Aster Kenea ◽  
Shuktika A. Nandkeolyar ◽  
...  

Skeletal muscle microtubules (MTs) form a nonclassic grid-like network, which has so far been documented in static images only. We have now observed and analyzed dynamics of GFP constructs of MT and Golgi markers in single live fibers and in the whole mouse muscle in vivo. Using confocal, intravital, and superresolution microscopy, we find that muscle MTs are dynamic, growing at the typical speed of ∼9 µm/min, and forming small bundles that build a durable network. We also show that static Golgi elements, associated with the MT-organizing center proteins γ-tubulin and pericentrin, are major sites of muscle MT nucleation, in addition to the previously identified sites (i.e., nuclear membranes). These data give us a framework for understanding how muscle MTs organize and how they contribute to the pathology of muscle diseases such as Duchenne muscular dystrophy.


2017 ◽  
Vol 10 (3) ◽  
pp. 99-106 ◽  
Author(s):  
Islam M. Sadiqul ◽  
Saimon Mohiful Kabir ◽  
Zannatul Ferdous ◽  
Khan Mst. Mansura ◽  
Rahman Md. Khalilur

AbstractAnin vivostudy was carried out on the freshwater fishBarbonymus gonionotusto evaluate the genotoxic effects of the organophosphate quinalphos. The fish were exposed to sub-lethal doses of quinalphos (0%, 10%, 25%, and 50% of LC50) for a period of 30 days. Analysis of biochemical characteristics (protein and lipid contents of different organs), nuclear abnormalities of erythrocytes (NAE) and morphological abnormalities of erythrocytes (MAE) were performed on peripheral erythrocytes sampled at post-treatment intervals of 0 and 30 days. The biochemical results revealed a significant dose-dependent decline in protein and lipid contents and increase in the frequencies of NAE as well as MAE. Our findings also confirmed that the morphological deformations of erythrocytes in addition to NAE on fish erythrocytesin vivoare effective tools in determining the potential genotoxicity of organophosphates.


2007 ◽  
Vol 35 (4) ◽  
pp. 411-420 ◽  
Author(s):  
Carsten Kneuer ◽  
Cathleen Lakoma ◽  
Walther Honscha

A battery of in vitro methods has been developed for the prediction of acute oral toxicity, to reduce the number of animals used for this purpose. However, the results of these tests correlate more closely with lethal serum concentrations than with lethal doses. To address this issue, we have further evaluated the HPCT-1E3 model, which may be better able to emulate toxicokinetic factors that occur in vivo, due to the presence in these hepatocytoma cells of endogenous transmembrane carriers and a basal activity of xenobiotic metabolism. IC50 values produced by using the MTT test after a 48-hour incubation with 20 randomly-selected MEIC substances, correlated better with human oral LD50 values than with LC50 data, supporting this hypothesis. As with other models, the toxicity of receptor-specific rather than cytotoxic substances, for example digoxin, was underpredicted. When digoxin was removed from the correlation analysis, the coefficient of determination (r2) improved to 0.81, and none of remaining chemicals were wrongly predicted by more than one order of magnitude. IC50 values obtained with HepG2 cells under similar conditions (MEIC Test No. 3, 24 hours, MTT) correlated with human LD50 data with a r2 value of 0.55. A direct comparison of HPCT-1E3 and HepG2 cells further suggested that the differences between them may be due to transport processes. In conclusion, the HPCT-1E3 model may be valuable in improving the prediction of lethal doses, rather than lethal serum concentrations.


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