OBJECTIVEThis study aims to establish and evaluate the methodology of isolated rabbit eye (IRE) test.

METHODSIRE test was performed according to modifications of the in vitro toxicology (INVITTOX) Protocol No.85: Rabbit enucleated eye test by European Centre for the Validation of Alternative Methods (ECVAM), and then 26 chemicals and 26 cosmetic products were tested in both in vitro IRE and in vivo Draize tests. A statistical analysis was conducted to determine the relevance of the IRE test to the data generated in the Draize test.

RESULTSIRE test was established successfully in our laboratory. It was shown that ranking correlation and class concordance were fairly well between the IRE test and the Draize test for 26 reference chemicals (Fisher's Exact Test χ(2)=51.314, P<0.001; McNemar P=0.261; Gamma=0.960, P<0.001; Kappa=0.843, P<0.001) and 26 cosmetic products (Fisher's Exact Test χ(2)=15.522, P<0.001; McNemar P=0.311; Gamma=0.967, P<0.001; Kappa=0.611, P<0.001).

CONCLUSIONIRE test was established successfully for in vitro testing of eye irritation as an alternative to Draize test.

Animal Testing Alternatives ; Animals ; Cosmetics ; toxicity ; Eye ; drug effects ; Irritants ; toxicity ; Rabbits ; Toxicity Tests ; methods

OBJECTIVEThe micronucleus test was applied to evaluate the genotoxicity of a new nanocomplex HA-PA66 root filling material in vitro.

METHODSThe dulbecco's modified eagle media(DMEM) extracts of the powder part and the mixture of the new nanomaterial were prepared separately. The V79 cell was used as the test cell and the mitomycin C(MMC) as the positive control. The MTT assay was employed in our study to evaluate the cytotoxic effect while the number of micronucleus was used as the criteria for the detection of genotoxocity.

RESULTSThe MTT values in test groups and negative group were not significantly different at different times (P > 0.05). The number of micronucleus in test groups (powder group: 6.1 +/- 1.1/1,000; complex group: 5.7 +/- 0.6/1,000) was similar to the negative control(5.3 +/- 0.8/1,000, P > 0.05), while they were significantly different to the positive control(123.9 +/- 8/1,000, P < 0.05).

CONCLUSIONThe new nanocomplex HA-PA66 root filling material showed no detectable cytotoxic and genotoxic effects in this study and was proved to be biocompatible.

Animals ; Biocompatible Materials ; toxicity ; Cricetinae ; Cricetulus ; Durapatite ; toxicity ; Micronucleus Tests ; methods ; Mutagenicity Tests ; methods ; Nanotechnology ; Nylons ; toxicity ; Root Canal Filling Materials ; toxicity

On the basis of web databases, 111 compounds with nephrotoxicity and 90 compounds without nephrotoxicity were collected as data set of nephrotoxicity discrimination model, 39 compounds with tubular necrosis and 39 compounds without tubular necrosis were collected as data set of tubular necrosis discrimination model. The 6 122 molecular descriptors, including physicochemical, charge distribution and geometrical descriptors were calculated to characterize the molecular structure of the above-mentioned compounds. CfsSubsetEval valuation method and BestFirst-D1-N5 searching method were used to select molecular descriptors. Two models with high accuracy were built based on the support vector machine (SVM) approach, respectively. Accuracy, sensitivity, specificity and matthew's correlation coefficient of the two models were all above 70%. By using 22 nephrotoxicity compounds of Chinese medicine, the nephrotoxicity discrimination model was further verified with an accuracy of 72.73%. Using the tubular necrosis discrimination model, 10 potential compounds which can cause tubular necrosis were screened from the positive results of nephrotoxicity discrimination model, 6 of them have been verified by literatures. The results demonstrated that the discrimination models can be applied to screen nephrotoxic compounds from Chinese medicinal materials, and they also offer a new research idea for the further studies on the mechanism of nephrotoxicity.
Drugs, Chinese Herbal ; toxicity ; Nephrons ; drug effects ; Support Vector Machine ; Toxicity Tests ; instrumentation ; methods

Animal Experimentation ; Animal Testing Alternatives ; methods ; Animal Welfare ; Animals ; Toxicity Tests ; methods

OBJECTIVETo investigate the fetotoxicity of retrorsine.

METHODMouse whole embryo culture (WEC) was applied. Post-implantation (8.5 d) mouse embryos were isolated from their mothers and put into the medium of immediately centrifuged serum (ICS) prepared from rats. Different concentrations of retrorsine (12.5, 25, 50, 100 mg x L(-1)) were added into the WEC culture. Development (yolk sac diameter, crown-rump length, head length, somite number) and organic morphodifferentiation (yolk sac circulation, allantois, embryonic flexion, heart, brain, optic-otic-olfactory organ, branchial arch, maxillary, mandible, bud) of embryos were observed at 48 h after treatment.

RESULTObvious fetotoxicity could be observed in various retrorsine treatment groups in a dose-dependent manner. Development of embryos was delayed significantly at dose 12.5-100 mg x L(-1). Malformations were shown in all organic morphodifferentiation indexes, especially in otic-olfactory organ, branchial arch, maxillary, mandible, bud.

CONCLUSIONRetrorsine had obvious fetotoxicity in vitro WEC culture, indicating that exposure of pregnant mice to retrorsine may have potential risk on fetals.

Animals ; Dose-Response Relationship, Drug ; Embryo, Mammalian ; drug effects ; Female ; Male ; Mice ; Pregnancy ; Pyrrolizidine Alkaloids ; toxicity ; Rats ; Toxicity Tests ; methods

OBJECTIVETo evaluate three alternative methods for LD50 test-Fixed Dose Procedure (FDP), the Acute Toxic Class Method (ATC) and Up and Down Procedure (UDP).

METHODSFemale SD rats (8-12 weeks of age, 160-200 g) were used. Three alternative methods from OECD were applied to assess 22 chemicals (10 cosmetic raw materials and 12 raw materials of personal and home care products). The toxicity ranking for tested chemicals was established according to Globally Harmonized System (GSH). The results LD50 test were compared for the consistency and correlation between alternative methods and traditional test.

RESULTSFor cosmetic raw materials, the concordance rate of the three alternative methods was 80% (8/10); for raw material of personal and home care products, the concordance rates of FDP, ATC and UDP was 91.7% (11/12), 75.0% (9/12) and 83.0% (10/12), respectively. The number of animals required in three alternative methods was significantly lower than that in traditional test (P < 0.05), but the time required in three alternative methods was significantly higher than that in traditional test (P < 0.05).

CONCLUSIONSHigh consistency and correlation were found between each alternative method and LD50 test. FDP may be more potential when applied to assess acute oral toxicity of cosmetic raw materials.

Administration, Oral ; Animals ; Cosmetics ; toxicity ; Dose-Response Relationship, Drug ; Female ; Hazardous Substances ; toxicity ; Lethal Dose 50 ; Rats ; Rats, Sprague-Dawley ; Toxicity Tests, Acute ; methods

Nanosilver antibiotic devices for gynecological external use are the third-class products of medical devices, whose biological safety and efficiency should be strictly controlled. But there is not yet the national standard or industry standard for the products to control the production process, so their testing method of biological evaluation mainly refers to GB/T16886 "The Guide to Implementation of Biological Evaluation of Medical Devices". To control the biological safety effectively, it's necessary to work out the testing items and methods of the biological evaluation for such products.
Animals ; Anti-Bacterial Agents ; toxicity ; BALB 3T3 Cells ; Equipment and Supplies ; adverse effects ; Female ; Male ; Mice ; Nanostructures ; Rabbits ; Silver ; toxicity ; Toxicity Tests ; methods

The immunoreaction caused by biomaterials or medical devices are even more concerned by people. It is necessary to establish the immune items in the biological evaluation of biomaterials and medical devices. And it is a tendency to use immune technique combined with molecular biological methods to evaluate the immunoreaction for biomaterials.
Biocompatible Materials ; adverse effects ; Equipment and Supplies ; adverse effects ; Immunity ; Materials Testing ; methods ; Toxicity Tests

BACKGROUNDThe cytotoxicity of dermal substitutes may be increased by the very processes used to deplete the cells. The present research aimed to investigate the method for monitoring the cytotoxicity of cell-free dermal substitutes using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) method.

METHODSThe cytotoxicity of four dermal substitutes was evaluated using the MTT method according to the standards set by the Chinese State Food and Drug Administration (SFDA). Swine acellular dermal matrix (SADM) and goat acellular dermal matrix (GADM) were produced using a repeated freeze-thaw method. Human dermal matrix glutaraldehyde composite (HADM-G) and SADM cross-linked with glutaraldehyde (SADM-G) were produced using conventional methods.

RESULTSThe cytotoxicity of all dermal substitutes ranged from Grade 0 to Grade 1, meeting the standards of the Chinese FDA. The OD(490) of both SADM and GADM was higher than that of either HADM-G or SADM-G (P < 0.05).

CONCLUSIONDermal substitutes produced by the freeze-thaw method are less cytotoxic than those produced using conventional methods.

Cell Line ; Humans ; Skin, Artificial ; adverse effects ; Tetrazolium Salts ; chemistry ; Toxicity Tests ; methods

To discuss IC50 application in cytotoxicity tests of medical devices, we firstly investigated the vibrating condition and endpoint of MTT method specified in ISO 10993-5: 2009. Furthermore, we demonstrated the application of IC50 in the result evaluation of MTT method. The experimental results show that usage of IC50 in quantitative evaluation of MTT method is feasible.
Equipment and Supplies ; adverse effects ; standards ; Inhibitory Concentration 50 ; Toxicity Tests ; methods