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Purpose The risk of radiation exposure is considered to have increased in recent years. For convenience and simple administration, development of an effective orally administered radioprotective agent is highly desirable. The steroid 5-androstene-3β, 17β-diol (5-AED) has been evaluated as both a radioprotector and a radiomitigator in mice and nonhuman primates; however, poor oral bioavailability has limited its development. A variant compound—17α-ethinyl-androst-5-ene-3β, 17β-diol (EAD)—exhibits significant oral bioavailability. We investigated the radioprotective effects of EAD via oral administration in mice. Methods and Materials Survival assays were performed in lethally (9.0-10.0 Gy) irradiated mice. Peripheral blood cell counts were monitored in lethally (9.5 Gy) or sublethally (6.5 Gy) irradiated mice. We performed histologic analysis of bone marrow (BM) and frequency and functional analysis of hematopoietic stem and progenitor cells in mice irradiated with 6.5 Gy. To investigate multilineage engraftment of irradiated hematopoietic stem cells after BM transplantation, competitive repopulation assays were conducted. Plasma granulocyte colony-stimulating factor was measured by enzyme-linked immunosorbent assay. Results Oral administration of EAD on 3 consecutive days before irradiation conferred 100% survival in mice, against otherwise 100% death, at a 9.5-Gy lethal dose of total body irradiation. EAD ameliorated radiation-induced pancytopenia at the same dose. EAD augmented BM cellular recovery and colony-forming ability, promoted hematopoietic stem and progenitor cell recovery, and expanded the pool of functionally superior hematopoietic stem cells in the BM of sublethally irradiated mice. Unlike 5-AED, EAD did not increase granulocyte colony-stimulating factor levels in mice and exhibited no therapeutic effects on hematologic recovery after irradiation; nevertheless, its radioprotective efficacy was superior to that of 5-AED. Conclusions Our findings demonstrate the radioprotective efficacy of EAD and reveal that the 17α-ethinyl group is essential for its oral activity. Given its oral efficacy and low toxicity, EAD has potential as an optimal radioprotector for use by first responders, as well as at-risk civilian populations.

Autocollimator is an important optical detection instrument, which is mainly used to measure small angle, and plays an important role in the field of optical equipment manufacturing and debugging. For many years, the autocollimation accuracy of collimator has been one of the factors affecting its performance. In order to improve the autocollimation accuracy of collimator optical axis, an auxiliary calibration method based on image recognition is proposed in this paper. And the concrete realization idea of this method is given. The accuracy of this method to detect and identify the optical axis eccentricity error can reach 0.1 pixel. Taking the detection data as reference to adjust the optical axis, the autocollimation accuracy of collimator optical axis can be greatly improved.

Consequences of primary dsysmenorrhea (PD) can be severe. Increased prostaglandin production leads to uterine contraction and insufficient blood flow to the endometrium causing ischemia and pain symptoms. Protein tyrosine kinase/phosphatase activities contribute to the modulation of uterine contraction. In our previous study, we found the synthetic β-methoxyacrylates compound Fluacrypyrim (FAPM), significantly increased protein tyrosine phosphatases (PTPs) activity, resulting in dephosphorylation of tyrosine kinases. In the present study, we found that FAPM near completely inhibited prostaglandin F2α (PGF2α)-, oxytocin-, acetylcholine-, and high K+-induced uterine contractions in rats in vitro, and decreased rat myometrial myosin light chain (MLC20) phosphorylation induced by PGF2α. A structure–activity relationship assay indicated that the β-methoxyacrylates structure of FAPM is crucial for the inhibition of PGF2α-induced uterine contractions. FAPM caused a concentration-dependent parallel rightward shift of the concentration–response curve induced by oxytocin, dose-dependently reduced the number of abdominal constrictions and increased the latency time in PGF2α- and acetic acid-induced writhing test in mice in vivo. Furthermore, FAPM considerably inhibited the development of Carr-induced rat paw edemas and thexylene-induced mouse ear edemas. Taken together, our results indicate that FAPM exerts antinociceptive and anti-inflammatory effects in vivo with considerable potential as a novel uterine relaxant.

α-tocopherol succinate (α-TOS), γ-tocotrienol (GT3) and δ-tocotrienol (DT3) have drawn large attention due to their efficacy as radioprotective agents. α-TOS has been shown to act superior to α-tocopherol (α-TOH) in mice by reducing lethality following total body irradiation (TBI). Because α-TOS has been shown to act superior to α-tocopherol (α-TOH) in mice by reducing lethality following total body irradiation (TBI), we hypothesized succinate may be contribute to the radioprotection of α-TOS. To study the contributions of succinate and to identify stronger radioprotective agents, we synthesized α-, γ- and δ-TOS. Then, we evaluated their radioprotective effects and researched further mechanism of δ-TOS on hematological recovery post-irradiation. Our results demonstrated that the chemical group of succinate enhanced the effects of α-, γ- and δ-TOS upon radioprotection and granulocyte colony-stimulating factor (G-CSF) induction, and found δ-TOS a higher radioprotective efficacy at a lower dosage. We further found that treatment with δ-TOS ameliorated radiation-induced pancytopenia, augmenting cellular recovery in bone marrow and the colony forming ability of bone marrow cells in sublethal irradiated mice, thus promoting hematopoietic stem and progenitor cell recovery following irradiation exposure. δ-TOS appears to be an attractive radiation countermeasure without known toxicity, but further exploratory efficacy studies are still required.