On Amalgam Toxicity

1990 ◽  
Vol 6 (3) ◽  
pp. 363-368 ◽  
Author(s):  
Per-Olof Glantz ◽  
Ivar A. Mjör

Toxicity implies an adverse effect. It may be caused by an overdose of any substance or combination of substances, either by an initial high dose or by the accumulation of a toxic substance over a long period of time. Thus, toxicity is dose dependent. It is also a relative term in that therisk involved must be evaluated and the available alternatives assessed.

Nutrients ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 1981 ◽  
Author(s):  
Qiufen Mo ◽  
Aikun Fu ◽  
Lingli Deng ◽  
Minjie Zhao ◽  
Yang Li ◽  
...  

Glycerol monolaurate (GML) has potent antimicrobial and anti-inflammatory activities. The present study aimed to assess the dose-dependent antimicrobial-effects of GML on the gut microbiota, glucose and lipid metabolism and inflammatory response in C57BL/6 mice. Mice were fed on diets supplemented with GML at dose of 400, 800 and 1600 mg kg−1 for 4 months, respectively. Results showed that supplementation of GML, regardless of the dosages, induced modest body weight gain without affecting epididymal/brown fat pad, lipid profiles and glycemic markers. A high dose of GML (1600 mg kg−1) showed positive impacts on the anti-inflammatory TGF-β1 and IL-22. GML modulated the indigenous microbiota in a dose-dependent manner. It was found that 400 and 800 mg kg−1 GML improved the richness of Barnesiella, whereas a high dosage of GML (1600 mg kg−1) significantly increased the relative abundances of Clostridium XIVa, Oscillibacter and Parasutterella. The present work indicated that GML could upregulate the favorable microbial taxa without inducing systemic inflammation and dysfunction of glucose and lipid metabolism.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Kathryn A. Ryan ◽  
Kevin R. Bewley ◽  
Susan A. Fotheringham ◽  
Gillian S. Slack ◽  
Phillip Brown ◽  
...  

AbstractThere is a vital need for authentic COVID-19 animal models to enable the pre-clinical evaluation of candidate vaccines and therapeutics. Here we report a dose titration study of SARS-CoV-2 in the ferret model. After a high (5 × 106 pfu) and medium (5 × 104 pfu) dose of virus is delivered, intranasally, viral RNA shedding in the upper respiratory tract (URT) is observed in 6/6 animals, however, only 1/6 ferrets show similar signs after low dose (5 × 102 pfu) challenge. Following sequential culls pathological signs of mild multifocal bronchopneumonia in approximately 5–15% of the lung is seen on day 3, in high and medium dosed groups. Ferrets re-challenged, after virus shedding ceased, are fully protected from acute lung pathology. The endpoints of URT viral RNA replication & distinct lung pathology are observed most consistently in the high dose group. This ferret model of SARS-CoV-2 infection presents a mild clinical disease.


2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Heather C. M. Allaway ◽  
Roger A. Pierson ◽  
Jesse Invik ◽  
Susan A. Bloomfield

Abstract Background Long-acting, reversible contraceptives (LARC; progestin only) are an increasingly common hormonal contraceptive choice in reproductive aged women looking to suppress ovarian function and menstrual cyclicity. The overall objective was to develop and validate a rodent model of implanted etonogestrel (ENG) LARC, at body size equivalent doses to the average dose received by women during each of the first 3 years of ENG subdermal rod LARC use. Methods Intact, virgin, female Sprague-Dawley rats (16-wk-old) were randomized to 1 of 4 groups (n = 8/group) of ENG LARC (high-0.30μg/d, medium-0.17μg/d, low-0.09μg/d, placebo-0.00μg/d) via a slow-release pellet implanted subcutaneously. Animals were monitored for 21 days before and 29 days following pellet implantation using vaginal smears, ultrasound biomicroscopy (UBM), saphenous blood draws, food consumption, and body weights. Data were analyzed by chi-square, non-parametric, univariate, and repeated measures 2-way ANOVA. Results Prior to pellet implantation there was no difference in time spent in estrus cycle phases among the treatment groups (p > 0.30). Following pellet implantation there was a dose-dependent impact on the time spent in diestrus and estrus (p < 0.05), with the high dose group spending more days in diestrus and fewer days in estrus. Prior to pellet insertion there was not an association between treatment group and estrus cycle classification (p = 0.57) but following pellet implantation there was a dose-dependent association with cycle classification (p < 0.02). Measurements from the UBM (ovarian volume, follicle count, corpora lutea count) indicate an alteration of ovarian function following pellet implantation. Conclusion Assessment of estrus cyclicity indicated a dose-response relationship in the shift to a larger number of acyclic rats and longer in duration spent in the diestrus phase. Therefore, each dose in this model mimics some of the changes observed in the ovaries of women using ENG LARC and provides an opportunity for investigating the impacts on non-reproductive tissues in the future.


Blood ◽  
1964 ◽  
Vol 23 (4) ◽  
pp. 471-487 ◽  
Author(s):  
T. M. FLIEDNER ◽  
GOULD A. ANDREWS ◽  
EUGENE P. CRONKITE ◽  
VICTOR P. BOND

Abstract 1. Serial marrow studies were performed during the first few days in eight men accidentally exposed to a mixed neutron gamma irradiation. They showed the occurrence of a wave of cytologic abnormalities. These were identical with those seen in animal experiments 1-3 days after whole body irradiation. They were considered to be "mitotically connected" (M. C. Abn.) and included the occurrence of chromosomal bridges and chromosomal fragments in mitoses. In interphase cells, the main abnormalities were nuclear fragments ("karyomeres") in the cytoplasm of erythroblasts, myelocytic cells and lymphocytes; bi- and multinucleated cells; and giant cells. The peak of abnormalities in the erythropoietic forms was reachéd after 2 days; that in the myelopoietic cells 4 days after exposure. On the 4th day, there was a distinct dose-dependent difference in these abnormalities between the high dose group (236-365 rads) and the low dose group (22-68 rads). 2. Some cytologic abnormalities, as seen in increased regeneratory activity of the marrow, were found in marrow smears 3.5 years after the accident, although the peripheral blood counts and mitotic indices of the marrow were within normal range. Their significance is obscure. 3. A careful cytologic evaluation of serially aspirated marrow samples during the first hours and days after whole body exposure proves to be an additional important aid in the assessment of the exposed individual and may well prove to be useful in determining the degree of injury and thus the prognosis.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 386
Author(s):  
Tung-Hu Tsai ◽  
Yu-Jen Chen ◽  
Li-Ying Wang ◽  
Chen-Hsi Hsieh

This study was performed to evaluate the interaction between conventional or high-dose radiotherapy (RT) and the pharmacokinetics (PK) of regorafenib in concurrent or sequential regimens for the treatment of hepatocellular carcinoma. Concurrent and sequential in vitro and in vivo studies of irradiation and regorafenib were designed. The interactions of RT and regorafenib in vitro were examined in the human hepatoma Huh-7, HA22T and Hep G2 cell lines. The RT–PK phenomenon and biodistribution of regorafenib under RT were confirmed in a free-moving rat model. Regorafenib inhibited the viability of Huh-7 cells in a dose-dependent manner. Apoptosis in Huh-7 cells was enhanced by RT followed by regorafenib treatment. In the concurrent regimen, RT decreased the area under the concentration versus time curve (AUC)regorafenib by 74% (p = 0.001) in the RT2 Gy × 3 fraction (f’x) group and by 69% (p = 0.001) in the RT9 Gy × 3 f’x group. The AUCregorafenib was increased by 182.8% (p = 0.011) in the sequential RT2Gy × 1 f’x group and by 213.2% (p = 0.016) in the sequential RT9Gy × 1 f’x group. Both concurrent regimens, RT2Gy × 3 f’x and RT9Gy × 3 f’x, clearly decreased the biodistribution of regorafenib in the heart, liver, lung, spleen and kidneys, compared to the control (regorafenib × 3 d) group. The concurrent regimens, both RT2Gy × 3 f’x and RT9Gy × 3 f’x, significantly decreased the biodistribution of regorafenib, compared with the control group. The PK of regorafenib can be modulated both by off-target irradiation and stereotactic body radiation therapy (SBRT).


Antioxidants ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 442
Author(s):  
Gunn-Guang Liou ◽  
Cheng-Chi Hsieh ◽  
Yi-Ju Lee ◽  
Pin-Hung Li ◽  
Ming-Shiun Tsai ◽  
...  

Acetaminophen (APAP) overdose induces acute liver damage and even death. The standard therapeutic dose of N-acetyl cysteine (NAC) cannot be applied to every patient, especially those with high-dose APAP poisoning. There is insufficient evidence to prove that increasing NAC dose can treat patients who failed in standard treatment. This study explores the toxicity of NAC overdose in both APAP poisoning and normal mice. Two inbred mouse strains with different sensitivities to propacetamol-induced hepatotoxicity (PIH) were treated with different NAC doses. NAC therapy decreased PIH by reducing lipid oxidation, protein nitration and inflammation, and increasing glutathione (GSH) levels and antioxidative enzyme activities. However, the therapeutic effects of NAC on PIH were dose-dependent from 125 (N125) to 275 mg/kg (N275). Elevated doses of NAC (400 and 800 mg/kg, N400 and N800) caused additional deaths in both propacetamol-treated and normal mice. N800 treatments significantly decreased hepatic GSH levels and induced inflammatory cytokines and hepatic microvesicular steatosis in both propacetamol-treated and normal mice. Furthermore, both N275 and N400 treatments decreased serum triglyceride (TG) and induced hepatic TG, whereas N800 treatment significantly increased interleukin-6, hepatic TG, and total cholesterol levels. In conclusion, NAC overdose induces hepatic and systemic inflammations and interferes with fatty acid metabolism.


1989 ◽  
Vol 256 (1) ◽  
pp. R276-R280 ◽  
Author(s):  
T. Gerardo-Gettens ◽  
B. J. Moore ◽  
J. S. Stern ◽  
B. A. Horwitz

Lactation in the rat is marked by pronounced hyperphagia and suppression of brown fat (BAT) thermogenic capacity. We previously examined the possibility that elevated prolactin levels mediate these changes. The present study evaluated the effect of varying prolactin levels on food intake, BAT mitochondrial GDP binding, and carcass adiposity. Female rats were injected daily for 10 days with ovine prolactin at one of three doses: high = 3.0, medium = 1.0, or low = 0.3 micrograms/g body wt. Controls were injected with 0.9% NaCl. A group of uninjected rats served as an additional control. Cumulative food intake was significantly elevated in a dose-dependent manner in the prolactin-treated animals relative to the saline-injected and uninjected controls. Compared with the saline controls, the mean cumulative food intake was greatest at the high dose (20% increase), intermediate at the medium dose (17%), and smallest at the low dose (12%). Prolactin-treated rats gained significantly more weight during the experiment than did controls. Despite the hyperphagia in the prolactin-treated rats, no significant differences in BAT mitochondrial GDP binding were observed among the five groups. These data indicate that elevated prolactin levels stimulate food intake in a dose-dependent manner and that this hyperphagia is not accompanied by an increase in BAT mitochondrial GDP binding.


1987 ◽  
Vol 17 (4) ◽  
pp. 869-873 ◽  
Author(s):  
C. Schmauss ◽  
J.-C. Krieg

SynopsisIn 17 benzodiazepine (BDZ) dependent in-patients a CT scan was performed before initiation of withdrawal therapy. The evaluation of the ventricular to brain ratio (VBR) by standardized and computerized measurements revealed significantly higher mean VBRs for both high-and low-dose BDZ-dependent patients compared to the mean VBR of an age- and sex-matched control group. In addition, the mean VBR of high-dose BDZ-dependent patients (N = 8) was significantly higher than the mean VBR of low-dose BDZ-dependent patients (N = 9). This difference could not be accounted for by the age of the patients or duration of BDZ-dependency and, therefore, suggests a dose-dependent effect of BDZs on the enlargement of internal CSF-spaces. On the other hand, higher values for the width of external CSF-spaces were found to be related to increasing age of the patients and duration of BDZ-dependency.


1996 ◽  
Vol 438 ◽  
Author(s):  
V. Krishnamoorthy ◽  
D. Venables ◽  
K. Moeller ◽  
K. S. Jones ◽  
B. Freer

Abstract(001) CZ silicon wafers were implanted with arsenic (As+) at energies of 10–50keV to doses of 2×1014 to 5×1015/cm2. All implants were amorphizing in nature. The samples were annealed at 700°C for 16hrs. The resultant defect microstructures were analyzed by XTEM and PTEM and the As profiles were analyzed by SIMS. The As profiles showed significantly enhanced diffusion in all of the annealed specimens. The diffusion enhancement was both energy and dose dependent. The lowest dose implant/annealed samples did not show As clustering which translated to a lack of defects at the projected range. At higher doses, however, projected range defects were clearly observed, presumably due to interstitials generated during As clustering. The extent of enhancement in diffusion and its relation to the defect microstructure is explained by a combination of factors including surface recombination of point defects, As precipitation, As clustering and end of range damage.


2017 ◽  
Vol 5 ◽  
pp. 2050313X1769599 ◽  
Author(s):  
Thomas J Reilly ◽  
Sean Cross ◽  
David M Taylor ◽  
Richard Haslam ◽  
Sophie C Tomlin ◽  
...  

Objectives: To describe a case of neuroleptic malignant syndrome following antipsychotic treatment of catatonia, highlighting the potentially serious complications of this rare adverse drug reaction. Methods: We present a case report of a patient who developed this syndrome with various sequelae. Results: The patient developed neuroleptic after being treated with lorazepam and olanzapine for catatonia. He subsequently developed the complications of rhabdomyolysis, acute kidney injury, pulmonary embolism, urinary retention and ileus. He received high-dose lorazepam, anticoagulation and intravenous fluids. Antipsychotic medication in the form of haloperidol was reinstated with no adverse effect, and he went on to make a full recovery. Conclusions: This case illustrates the potential life-threatening complications of neuroleptic malignant syndrome and the need for a low index of clinical suspicion. It also highlights the lack of evidence for treatment of catatonia, including the use of antipsychotics.


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