Effect of different exposure times and doses of cyantraniliprole on oxidative stress and genotoxicity in earthworms (Eisenia fetida)

Cyantraniliprole, the second generation of diamide insecticides, is widely used to control various pests, which will certainly result in adverse effects on earthworms in soil. In this study, after exposure with six doses of cyantraniliprole (0, 0.5, 1, 2.5, 5, and 10 mg kg^-1) by artificial soil method, six biomarkers, four functional genes, and histopathological changes of Eisenia fetida were measured on the 7th, 14th, 21st, and 28th days. The comprehensive toxicity was assessed by the IBR version 2 (IBRv2) method. The results showed that the reactive oxygen species (ROS) level was induced significantly. The superoxide dismutase (SOD) activity was activated in 7-28 days. The catalase (CAT) and glutathione S-transferases (GST) activities were also activated in the initial 14 days. The 8-hydroxy-2'-deoxyguanosine (8-OHdG) and malondialdehyde (MDA) contents in the high treatment increased until the late stage of exposure. On the 28th day, the metallothionein (MT) and calreticulin (CRT) genes were up-regulated, the transcriptionally controlled tumor protein (TCTP) gene was down-regulated. The SOD gene showed a good correlation with SOD activity. Extensive histopathological damage was found in the endoderm and ectoderm of E. fetida. The 5 and 10 mg kg^-1 treatments showed higher comprehensive toxicity than the 0.5, 1, and 2.5 mg kg^-1 treatments on the 28th day. These results suggest that cyantraniliprole exerted certain subchronic toxic effects of oxidative stress, DNA damage, and histopathological changes to E. fetida, which provided theoretical basis for rational use of cyantraniliprole and evaluation of its safety to soil environment.

Misdiagnosed dystrophic epidermolysis bullosa pruriginosa: A case report

BACKGROUND

Dystrophic epidermolysis bullosa pruriginosa (DEB-Pr) is a rare subtype of DEB, characterized by recurrent pruritus of the extremities, pruritus papules, nodules, and mossy-like plaques. To date, fewer than 100 cases have been reported. We report a misdiagnosed 30-year-old man with sporadic late-onset DEB-Pr who responded well to tacrolimus treatment, thereby serving as a guide to correct diagnosis and treatment.

CASE SUMMARY

A 30-year-old man presented with recurrent itching plaques of 1-year duration in the left tibia that aggravated and involved both legs and the back. Examination revealed multiple symmetrical, purple, and hyperpigmented papules and nodules with surface exfoliation involving the tibia and dorsum of the neck with negative Nissl's sign, no abnormalities in the skin, mucosa, hair, or fingernail, and no local lymph node enlargement. Blisters were never reported prior to presentation. Serum immunoglobulin E level was 636 IU/mL. Clinical manifestations suggested DEB-Pr. Histological examination showed subepidermal fissure, scar tissue, and milia. Direct immunofluorescence showed no obvious abnormalities. However, we were unable to perform electron microscopy or genetic research following his choice. We treated him with topical tacrolimus. After 2 wk, the itching alleviated, and the skin lesions began to subside. No adverse reactions were observed during treatment.

CONCLUSION

Topical tacrolimus is a safe treatment option for patients with DEB-Pr and can achieve continuous relief of severe itching.