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This study investigated the nature and mechanism of juglone-induced apoptosis in the human breast cancer cell line MCF-7. The inhibitory effect of juglone on MCF-7 cell growth was evaluated by the dimethylthiazol tetrazolium assay. Morphological apoptotic changes were characterized using an inverted microscope, Hoechst 33258 fluorescence staining, and Giemsa staining. The rate of cell apoptosis, intracellular levels of reactive oxygen species (ROS), and mitochondrial membrane potential were detected using flow cytometry. Intracellular Ca(2+) concentrations were detected using laser scanning confocal fluorescence microscopy. Expression of the proteins Bcl-2, Bax, and cytochrome C was assessed by western blotting. Caspase-3 activity was quantified using a caspase-3 activity kit. Juglone inhibited the growth of MCF-7 cell line with an IC50 of 11.99 µM. The rates of MCF-7 cell apoptosis at 24 h after exposure to 5, 10, and 20 µM juglone were 9.29, 20.67, and 28.39%, respectively; compared to unexposed cells, juglone-exposed cells exhibited significant elevation in intracellular ROS level, decrease in mitochondrial membrane potential, and increase in intracellular Ca(2+) concentration. Juglone upregulated the expression of Bax, and downregulated the expression of Bcl-2, promoting the release of cytochrome C, thereby upregulating the activity of caspase-3. The results suggest that the mechanism of juglone-induced apoptosis in MCF-7 cells is characterized by elevated ROS levels, reduced Bcl-2 expression, increased Bax expression, decreased mitochondrial membrane potential, increased intracellular Ca(2+) concentration, outer mitochondrial-membrane rupture, cytochrome C release, and caspase-3 activation.

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A mathematical model was presented in this paper for the combustion of municipal solid waste in a novel two-stage reciprocating grate furnace. Numerical simulations were performed to predict the temperature, the flow and the species distributions in the furnace, with practical operational conditions taken into account. The calculated results agree well with the test data, and the burning behavior of municipal solid waste in the novel two-stage reciprocating incinerator can be demonstrated well. The thickness of waste bed, the initial moisture content, the excessive air coefficient and the secondary air are the major factors that influence the combustion process. If the initial moisture content of waste is high, both the heat value of waste and the temperature inside incinerator are low, and less oxygen is necessary for combustion. The air supply rate and the primary air distribution along the grate should be adjusted according to the initial moisture content of the waste. A reasonable bed thickness and an adequate excessive air coefficient can keep a higher temperature, promote the burnout of combustibles, and consequently reduce the emission of dioxin pollutants. When the total air supply is constant, reducing primary air and introducing secondary air properly can enhance turbulence and mixing, prolong the residence time of flue gas, and promote the complete combustion of combustibles. This study provides an important reference for optimizing the design and operation of municipal solid wastes furnace.

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Eight hundred and two digits (592 complete amputation and 210 incomplete amputations) of 549 patients were replanted. The male to female ratio was 3:1 and the age range 1-63 years. 728 digits survived and 74 digits failed. The overall survival rate was 90.8%. Special varieties of complicated amputation were encountered in this series: (1) distal segment replantation, 139 digits, 131 digits (94%) survived; (2) digital replantation of children, 45 cases, 78 digits, average age 3.8 years, the youngest being 1 year old, 68 digits survived (88.7%); (3) rotational avulsion amputation of thumb, 26 digits, 23 digits (88.4%) survived; (4) bilateral digit amputation, 8 cases, 44 digits amputated, 38 digits replanted, including 9 digits of a ten-digit guillotined case. All the digits were salvaged. We conclude that thorough debridement, meticulous anastomosis of blood vessels and timely management of vascular crisis are keys to high survival rate, while judicious selection of indication, proper internal fixation of bone, anastomosis of as many blood vessels as possible, attentive repair of nerves and tendons, sound rehabilitation program are important measures in improving postoperative function.

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Sixty-four digits amputated at or distal to the distal interphalangeal joint were reimplanted in 57 patients with the use of microsurgical techniques. Five patients were children under 3 years of age. The percentage of survival was 96.9%. Before the operation, the surgical anatomy of the amputated digits was studied and particular attention was focused on the microvasculature. Equal emphasis was given to the reinnervation and revascularization of the amputated digits.

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Since 1978 a series of 15 avulsively amputated thumbs were replanted with survival of the replantation in 14 patients. Good restoration of sensory and motor functions for these patients eradicates the old concept that replantation for avulsively amputated digits is contraindicated or a poor risk. We emphasize the importance of proper management of the transfer technique of the severed tendons, nerves, and blood vessels during the replantation. Details are described. The only failure was a result of technical faults. We conclude that replantation of an avulsively amputated thumb is worthwhile and will be beneficial to the patient.

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Three cases of mutilating injury of the distal end of the forearm, wrist, and palm treated by transplantation of severed digits to the forearm stump are reported. Follow-up examinations made at 1 year and 4 months to 31/2 years postoperatively revealed fair sensory and motor functions. The functional result is better than that obtained after Krukenberg's operation or prosthesis fitting, and is comparable to that of "hand" reconstruction by autotransplantation of toes. Since this procedure can fulfill the basic requirements of hand function by reconstruction, namely, good sensibility; basic motor functions of pinching, grasping, and powerful gripping; and acceptable outward appearance, and can be accomplished in a one-stage operation without sacrificing toes, it should be considered as first choice whenever a suitable case is encountered.

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