T necrotic phenomena were not reported here. In the present study, HE stain, TUNEL and TEM figures further showed that Cd treatment led to damages of cell in gill, including the separation of the upper and lower monolayer cells of gill lamellae, edema in gill lamellae, enlargement of the gill cavity at 24 h, abnormity of gill lamellae and apoptotic cell death with nuclei condensation of epithelial cells at 48 h, necrotic cell death of epithelial cells with the decrease in the number of epithelial cells, gill cavity swelling, and the induction of an inflammatory response at 72 and 96 h. The above results suggest that the duration of Cd exposure and the oxidative state seem to be critical in determining the mode of death. The result was consistent with that of Ishido et al. [42], who demonstrated that Cd induced apoptotic chromatin condensation at an early stage of exposure, followed by necrotic features of the cells. A transient oxidation may suffice to trigger apoptosis. By contrast, necrosis requires not only an increase in intensity, but also that the oxidative state stays on. Several reports confirm that excessive oxidation may Title Loaded From File deplete the cells in ATP, prevent the induction of apoptosis and drive the cells into necrosis [16,40]. Besides, inactivating caspases provoked by excessive ROS and MT could play a role in controlling the choice between apoptosis and necrosis [41,43,44]. At any rate, Cd led to oxidative stress and celldeath in crab gills. Prolonging exposure time of Cd failed to further increase apoptosis but resulted in elevated necrosis.ConclusionAcute Cd exposure leads to the accumulation of Cd in the crab gill. At the initial state of Cd exposure, as one of the important detoxification mechanisms, MT and the antioxidant defense system are activated and decrease the free Cd ion level and caused a low cellular ROS content initially at 24 h. With increased exposure time, the toxicity of Cd exceeded the detoxification capacity of MT and that of the antioxidant defense system, which resulted in the accumulation of ROS. Once cell damage became more serious, lipid peroxidation and histopathological alternations were observed after 24 h. The cells appeared apoptotic after 48 h of Cd exposure, and exhibited necrotic and inflammatory characteristics after 72 h exposure time.AcknowledgmentsWe thank Wenwen Lei and Tuan Xu for assistance with histology. Thanks Profs. Enmin Zou and Hans-U. Dahms for language editing during the preparation of the manuscript.Author Title Loaded From File ContributionsConceived and designed the experiments: LW JW QW. Performed the experiments: LW JW PZ QS QW DL JL. Analyzed the data: JW PZ QS QW DL. Contributed reagents/materials/analysis tools: JW PZ QS QW. Wrote the paper: LW JW QW.
Radiotherapy is an important function in the treatment of breast cancer and its role has been extensively studied during the last several decades [1], [2]. Clinical studies have demonstrated a major benefit of adjuvant radiotherapy in increasing disease-free survival (DFS) and overall survival (OS) in breast cancer [2], and cellular radiosensitivity is an area of intense research in radiation oncology. In particular, chromosomes, which comprise the cellular cytogenetic information center, are one of the primary targets of radiation injury [3]. Telomeres, which are regions at the termini of chromosomes, are composed of TTAGGG repetitive DNA sequences and a variety of binding proteins [4]. Telomerase, is a ribonucleoprotein enzyme that synthesizes tel.T necrotic phenomena were not reported here. In the present study, HE stain, TUNEL and TEM figures further showed that Cd treatment led to damages of cell in gill, including the separation of the upper and lower monolayer cells of gill lamellae, edema in gill lamellae, enlargement of the gill cavity at 24 h, abnormity of gill lamellae and apoptotic cell death with nuclei condensation of epithelial cells at 48 h, necrotic cell death of epithelial cells with the decrease in the number of epithelial cells, gill cavity swelling, and the induction of an inflammatory response at 72 and 96 h. The above results suggest that the duration of Cd exposure and the oxidative state seem to be critical in determining the mode of death. The result was consistent with that of Ishido et al. [42], who demonstrated that Cd induced apoptotic chromatin condensation at an early stage of exposure, followed by necrotic features of the cells. A transient oxidation may suffice to trigger apoptosis. By contrast, necrosis requires not only an increase in intensity, but also that the oxidative state stays on. Several reports confirm that excessive oxidation may deplete the cells in ATP, prevent the induction of apoptosis and drive the cells into necrosis [16,40]. Besides, inactivating caspases provoked by excessive ROS and MT could play a role in controlling the choice between apoptosis and necrosis [41,43,44]. At any rate, Cd led to oxidative stress and celldeath in crab gills. Prolonging exposure time of Cd failed to further increase apoptosis but resulted in elevated necrosis.ConclusionAcute Cd exposure leads to the accumulation of Cd in the crab gill. At the initial state of Cd exposure, as one of the important detoxification mechanisms, MT and the antioxidant defense system are activated and decrease the free Cd ion level and caused a low cellular ROS content initially at 24 h. With increased exposure time, the toxicity of Cd exceeded the detoxification capacity of MT and that of the antioxidant defense system, which resulted in the accumulation of ROS. Once cell damage became more serious, lipid peroxidation and histopathological alternations were observed after 24 h. The cells appeared apoptotic after 48 h of Cd exposure, and exhibited necrotic and inflammatory characteristics after 72 h exposure time.AcknowledgmentsWe thank Wenwen Lei and Tuan Xu for assistance with histology. Thanks Profs. Enmin Zou and Hans-U. Dahms for language editing during the preparation of the manuscript.Author ContributionsConceived and designed the experiments: LW JW QW. Performed the experiments: LW JW PZ QS QW DL JL. Analyzed the data: JW PZ QS QW DL. Contributed reagents/materials/analysis tools: JW PZ QS QW. Wrote the paper: LW JW QW.
Radiotherapy is an important function in the treatment of breast cancer and its role has been extensively studied during the last several decades [1], [2]. Clinical studies have demonstrated a major benefit of adjuvant radiotherapy in increasing disease-free survival (DFS) and overall survival (OS) in breast cancer [2], and cellular radiosensitivity is an area of intense research in radiation oncology. In particular, chromosomes, which comprise the cellular cytogenetic information center, are one of the primary targets of radiation injury [3]. Telomeres, which are regions at the termini of chromosomes, are composed of TTAGGG repetitive DNA sequences and a variety of binding proteins [4]. Telomerase, is a ribonucleoprotein enzyme that synthesizes tel.
