Abstract：
:Rates of alkaline hydrolysis of 18 natural or semisynthetic pyrrolizidine alkaloids, all retronecine diesters, have been compared. Steric hindrance around the ester groups was the major factor inhibiting hydrolysis. Relative rates of hydrolysis by esterases in a rat liver homogenate were also dependent on steric hindrance. However, in a series of less hindered esters with unbranched acids, hydrolysis rates increased with chain length to a maximum for the valeryl diester. Enzymic hydrolysis of retronecine di-isovalerate occurred primarily at the allylic 9-ester group. The results supported the view that a factor contributing to the lower hepatoxicity of semisynthetic retronecine diesters compared with some natural pyrrolizidine alkaloids, is their greater susceptibility to detoxication by hydrolysis.
journal_name
Toxicol Lettjournal_title
Toxicology lettersauthors
Mattocks ARdoi
10.1016/0378-4274(82)90017-0subject
Has Abstractpub_date
1982-11-01 00:00:00pages
111-6issue
1-2eissn
0378-4274issn
1879-3169pii
0378-4274(82)90017-0journal_volume
14pub_type
杂志文章abstract：:Exposition to cadmium (Cd) has been linked to bone metabolism alterations and occurrence of osteoporosis. Despite its known renal toxicity which indirectly disrupts bone metabolism through impairment of vitamin D synthesis, increasing evidence argues for the direct action of Cd on bone-forming osteoblasts. Indeed, acc...
journal_title：Toxicology letters
pub_type： 杂志文章
doi：10.1016/j.toxlet.2012.10.006
更新日期：2012-12-17 00:00:00
abstract：:The upregulated α-synuclein (α-syn) and Tau co-occur in methamphetamine (METH) abusers' brains. Here, we designed experiments mainly to investigate whether α-syn and Tau interact in METH exposure. We detected the expression of α-syn, total Tau, and phosphorylation of Tau at Serine 396 (pSer396 Tau) under in vitro and ...
journal_title：Toxicology letters
pub_type： 杂志文章
doi：10.1016/j.toxlet.2019.11.028
更新日期：2020-02-01 00:00:00
abstract：:The effects of sodium tellurite 0.1 and 0.4 mg/kg were assessed in the Morris water maze. Two days after treatment rats were tested for acquisition (posttreatment days 3-6) and on seventh day on a spatial retention task. Tellurium treatment was found to cause significant impairment in retention of the spatial learning...
journal_title：Toxicology letters
pub_type： 杂志文章
doi：10.1016/s0378-4274(02)00050-4
更新日期：2002-05-28 00:00:00
abstract：:This paper compares two methods for global optimization of physiologically based toxicokinetic models: Monte Carlo optimization, which searches randomly for the optimum; and the simplex method, which updates systematically an array of parameter values. Two measures of goodness-of-fit are also contrasted: criterion fun...
journal_title：Toxicology letters
pub_type： 杂志文章
doi：10.1016/0378-4274(93)90103-5
更新日期：1993-08-01 00:00:00
abstract：:Betulinic acid (BA) is known to induce apoptosis in melanoma neuroectodermal and malignant brain cancer cell lines. Present report describes the role of antioxidants on the BA-induced toxicity to human cell line SK-N-MC. Hydrophilic antioxidants viz., L-ascorbic acid (VitC) and N-acetyl-L-cysteine (l-NAC) had no prote...
journal_title：Toxicology letters
pub_type： 杂志文章
doi：10.1016/j.toxlet.2004.03.027
更新日期：2004-11-02 00:00:00
abstract：:Methylglyoxal (MG) is a metabolite of glucose. The serum MG level is increased in diabetic patients, and MG is implicated in diabetic complications related to embryonic development injury. We previously reported cytotoxic effects of MG on mouse embryonic stem cells and blastocysts, and a further association with defec...
journal_title：Toxicology letters
pub_type： 杂志文章
doi：10.1016/j.toxlet.2010.01.007
更新日期：2010-04-01 00:00:00
abstract：:Clinical epidemiological studies have shown that there is a link between Parkinson's disease (PD) and cancer, but how PD regulates cancer development remains unknown. In our study, the effect of metabotropic glutamate receptor 5 (mGlu5) on hepatoma was explored in a rotenone-induced PD model both in vitro and in vivo....
journal_title：Toxicology letters
pub_type： 杂志文章
doi：10.1016/j.toxlet.2018.02.019
更新日期：2018-05-15 00:00:00
abstract：:Reports on adverse health effects related to occupational exposure to toner powder are still inconclusive. Therefore, we have previously conducted an in vitro-study to characterize the genotoxic potential of three commercially available black printer toner powders in A549 lung cells. In these cell-based assays it was ...
journal_title：Toxicology letters
pub_type： 杂志文章
doi：10.1016/j.toxlet.2012.11.018
更新日期：2013-02-04 00:00:00
abstract：:Dysregulated cell proliferation and tumorigenesis is frequently encountered in several cancers including hepatocellular carcinogenesis (HCC). Thus, agents that inhibit cell proliferation and restrain hepatic tumorigenesis through cell cycle regulation have a beneficial effect in the treatment of hepatocellular carcino...
journal_title：Toxicology letters
pub_type： 杂志文章
doi：10.1016/j.toxlet.2013.08.018
更新日期：2013-10-23 00:00:00
abstract：:Aluminum (Al) is a toxic metal, and excessive Al accumulation causes immunosuppression. Deferiprone (DFP) is a well-known chelator and used in dialysis patients for removing Al from tissues. The present study aimed to investigate whether DFP treatment can attenuate immunotoxicity induced by aluminum chloride (AlCl3) i...
journal_title：Toxicology letters
pub_type： 杂志文章
doi：10.1016/j.toxlet.2018.01.007
更新日期：2018-03-15 00:00:00
abstract：:Biological monitoring in humans (HBM) is widely used in the field of occupational and environmental health. In the situation of an unexpected release of hazardous materials HBM may contribute to the medical support and treatment of exposed individuals from the general population or of emergency responders. Such exposu...
journal_title：Toxicology letters
pub_type： 杂志文章
doi：10.1016/j.toxlet.2014.03.002
更新日期：2014-12-15 00:00:00
abstract：:The effect of aflatoxin B1 on the uptake and incorporation of [3H]leucine and [3H]uridine and on phagocytosis of latex particles was studied using cultures of rat liver macrophages (Kuffer cells). Aflatoxin B1 inhibited the incorporation of both isotopes, but inhibition of uridine incorporation was greater than that o...
journal_title：Toxicology letters
pub_type： 杂志文章
doi：10.1016/0378-4274(85)90039-6
更新日期：1985-12-01 00:00:00
abstract：BACKGROUND:Di-2-ethylhexyl-terephtalate (DEHT) is a general purpose plasticizer and a structural isomer to di-2-ethylhexyl phthalate (DEHP) being known for its toxicity. Despite the fact that DEHT is used in quite a number of synthetics for medical device production including equipment for intravenous administration, t...
journal_title：Toxicology letters
pub_type： 杂志文章
doi：10.1016/j.toxlet.2011.04.020
更新日期：2011-08-10 00:00:00
abstract：:The neurotoxic, genotoxic and carcinogenic effects of industrial exposure to acrylamide have been studied in animals and humans for more than 30 years. A recent search for the cause of high background levels of acrylamide in industrially unexposed people revealed that it is formed during the frying or baking of foods ...
journal_title：Toxicology letters
pub_type： 杂志文章
doi：10.1016/j.toxlet.2004.04.037
更新日期：2004-09-10 00:00:00
abstract：:Induction of endotoxin tolerance in rats led to reductions in bile flow and BSP excretion. BSP serum retention or storage of BSP in the liver was not affected. Although serum alanine aminotransferase (ALT) activity was slightly elevated in endotoxin-tolerant rats, the levels of serum aspartate amino-transferase (AST) ...
journal_title：Toxicology letters
pub_type： 杂志文章
doi：10.1016/0378-4274(82)90151-5
更新日期：1982-05-01 00:00:00
abstract：:Behavioral endpoints offer special challenges to toxicology. One arises from the sometimes conflicting ways in which adverse effects may be expressed. For example, both increases and decreases in response rates of schedule-controlled performance may be produced by a specific agent, depending on the specific schedule. ...
journal_title：Toxicology letters
pub_type： 杂志文章
doi：10.1016/0378-4274(88)90034-3
更新日期：1988-10-01 00:00:00
abstract：:In this study, the action of 3-nitropropionic acid (3-NP) on the parameters of the cortical and peripheral evoked potentials was investigated in rats in different administration schemes (20 mg/kg i.p. during recording or 24 h before, and 5x 15 mg/kg daily 28 days before recording) to elucidate some neurophysiological ...
journal_title：Toxicology letters
pub_type： 杂志文章
doi：10.1016/j.toxlet.2005.07.006
更新日期：2006-01-25 00:00:00
abstract：:A physiologically based pharmacokinetic (PBPK) model describing the disposition of 2-butoxyethanol (2-BE) was developed in order to predict the urinary concentration of its major metabolite, butoxyacetic acid (BAA) under a range of exposure scenarios. Based on Corley et al. [Corley, R.A., Bormett, G.A., Ghanayem, B.I....
journal_title：Toxicology letters
pub_type： 杂志文章
doi：10.1016/j.toxlet.2005.09.012
更新日期：2006-04-10 00:00:00
abstract：:In this study, we examined the cytotoxic effects of sanguinarine, a phytoalexin with antimicrobial, anti-oxidant, anti-inflammatory and pro-apoptotic effects, on the blastocyst stage of mouse embryos, subsequent embryonic attachment and outgrowth in vitro and in vivo implantation via embryo transfer. Blastocysts treat...
journal_title：Toxicology letters
pub_type： 杂志文章
doi：10.1016/j.toxlet.2011.06.018
更新日期：2011-09-10 00:00:00
abstract：:One of the major side effects of aminoglycoside antibiotics (AG) is ototoxicity. The authors review the literature revealing many controversies on every aspect of this side-effect. Although epidemiological studies have to face the problem of reliable evaluation techniques, the incidence of cochleo- and vestibulotoxic ...
journal_title：Toxicology letters
pub_type： 杂志文章,评审
doi：10.1016/0378-4274(90)90033-i
更新日期：1990-08-01 00:00:00
abstract：:A considerable body of research over the past fifteen years establishes that in laboratory animals the Ah (aromatic hydrocarbon) receptor (AhR) mediates most, if not all, toxic effects of halogenated aromatic hydrocarbons such as polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and polyhalogenated bip...
journal_title：Toxicology letters
pub_type： 杂志文章,评审
doi：10.1016/0378-4274(94)90139-2
更新日期：1994-01-01 00:00:00
abstract：:The classical way to demonstrate the efficiency of remediation is measuring the reduction of toxic compounds in the environment. Nevertheless, more important is the risk reduction in human health. To determine changing health effects, exposure and bio-effects have to be monitored at time of and during remediation. Kin...
journal_title：Toxicology letters
pub_type： 杂志文章
doi：10.1016/j.toxlet.2005.09.017
更新日期：2006-04-10 00:00:00
abstract：:Effective treatments for esophageal squamous cell carcinoma (ESCC), one of the most common cancers in China, are lacking. Longikaurin A (LK-A), an ent-kauranoid diterpenoid isolated from Isodon ternifolius, has been shown to have potent cytotoxic effects on ESCC cells both in vivo and in vitro, mainly by inducing apop...
journal_title：Toxicology letters
pub_type： 杂志文章
doi：10.1016/j.toxlet.2017.08.005
更新日期：2017-10-05 00:00:00
abstract：:Benzophenone-3 (2-hydroxy-4-methoxybenzophenone, BZ-3) is a UV absorber that is used extensively in medicine, cosmetics and industry as a sunscreen and color fastener. Exposure to the chemical is through the dermal and oral route. Bioavailability of the chemical absorbed through the skin is different from that seen th...
journal_title：Toxicology letters
pub_type： 杂志文章
doi：10.1016/0378-4274(94)90101-5
更新日期：1994-08-01 00:00:00
abstract：:Ethylene (ET) is the largest volume organic chemical. Mammals metabolize the olefin to ethylene oxide (EO), another important industrial chemical. The epoxide alkylates macromolecules and has mutagenic and carcinogenic properties. In order to estimate the EO burden in mice, rats, and humans resulting from inhalation e...
journal_title：Toxicology letters
pub_type： 杂志文章
doi：10.1016/j.toxlet.2017.07.896
更新日期：2018-04-01 00:00:00
abstract：:By the gas plant at Schwaan (a small city near Rostock), tar and other by-products were released into the river Warnow which supplies Rostock with drinking water 20 km downstream. The tar-contaminated river sediment contained phenols and polycyclic aromatic hydrocarbons (PAH), indicating a mutagenic potential. Investi...
journal_title：Toxicology letters
pub_type： 杂志文章
doi：10.1016/0378-4274(96)03761-7
更新日期：1996-11-01 00:00:00
abstract：:Cytotoxicity in terms of haemolytic potency in vitro of eight surfactants failed to correlate with in vivo rabbit eye irritancy. Ability of the same surfactants to block spontaneous contractions of mouse and rabbit isolated ileum (especially the latter), correlated better with in vivo findings in rabbit eyes. Effectiv...
journal_title：Toxicology letters
pub_type： 杂志文章
doi：10.1016/0378-4274(83)90062-0
更新日期：1983-08-01 00:00:00
abstract：:Mercury(II) ions are known to accumulate in the kidney and their effect upon the renin-angiotensin system has also been described. The question, however, whether mercury(II) also exerts direct effect on the juxtaglomerular cells (JGC) to induce renin release remained to be answered. Suspension of isolated glomeruli wa...
journal_title：Toxicology letters
pub_type： 杂志文章
doi：10.1016/0378-4274(96)03637-5
更新日期：1996-04-01 00:00:00
abstract：:The people studied were male volunteers without occupational and dietary exposure to PAH: 27 smokers (10 cigarettes or more) and 27 non-smokers matched for age and socio-professional category. For each person, all the 24h voided urine samples were reassembled in a single sample. 1-Hydroxypyrene (1-OHPy) and 3-hydroxyb...
journal_title：Toxicology letters
pub_type： 杂志文章
doi：10.1016/j.toxlet.2005.09.019
更新日期：2006-04-10 00:00:00
abstract：:Propylene oxide (PO) concentrations >or=300 ppm induced cell proliferation and tumors in rat nasal respiratory epithelium (NRE). Cell proliferation was suggested to result from depletion of glutathione (GSH) in NRE. In order to substantiate this hypothesis, cell proliferation - measured by bromodeoxyuridine incorporat...
journal_title：Toxicology letters
pub_type： 杂志文章
doi：10.1016/j.toxlet.2009.01.009
更新日期：2009-03-28 00:00:00
