Low mitochondrial DNA copy number of resected cecum appendix correlates with high severity of acute appendicitis.

BACKGROUND/PURPOSE: The roles of mitochondrial DNA alterations in acute appendicitis (AA) remain unclear. We evaluated the alterations of mtDNA copy number and mtDNA integrity [proportion of mtDNA templates without 8-hydroxyl-2'-deoxyguanosine (8-OHdG)] of the resected cecum appendixes in clinically suspected acute appendicitis (CSAA). METHODS: A total of 228 CSAA patients, including 50 harbored negative AA (NAA), 155 true AA (TAA) without rupture and 23 TAA with rupture, who underwent appendectomies were enrolled. Tissues of resected cecum appendixes from the paraffin-embedded pathological blocks were subjected to DNA extraction, and their mtDNA copy number and mtDNA integrity were determined by quantitative real-time polymerase chain reaction (Q-PCR). RESULTS: During the progression of disease severity from NAA to TAA without rupture and further TAA with rupture, increases of white blood cell (WBC) counts (p = 0.001), positive bacterial culture rates in turbid ascites (p = 0.016) and area (p < 0.001)/or volume (p < 0.001) indices of resected cecum appendixes were noted among CSAA patients. On the contrary, decrease of mtDNA copy number (p = 0.003) was observed during disease progression of CSAA patients, especially in female patients (p = 0.007). Furthermore, lower mtDNA copy numbers were correlated with higher WBC counts (p = 0.001) and larger area (p = 0.003) or volume (p < 0.001) indices of the resected cecum appendixes. However, such an alteration was not observed in mtDNA integrity of resected cecum appendixes. CONCLUSION: We conclude that a low mtDNA copy number of the resected cecum appendix may reflect high severity of acute appendicitis.

Associated microsatellite alterations in mitochondrial DNA and in TP53 in thoracic esophageal squamous cell carcinoma.

We investigated the microsatellite alterations in mitochondrial DNA (mtDNA) and in TP53 in thoracic esophageal squamous cell carcinomas (TESCC). Using laser microdissection, 66 paired non-cancerous esophageal muscles, non-cancerous esophageal mucosa, cancerous TESCC nests plus 35 metastatic lymph nodes harvested from 66 resected esophagi of TESCC patients were subjected to DNA extraction. D310 and D17S960 were chosen as markers to address microsatellite alterations in mtDNA, including changes in copy number and homoplasmic/heteroplasmic mutations of mtDNA, and in TP53, including loss of heterozygosity (LOH) and microsatellite instability (MI). From non-cancerous esophageal mucosa to cancerous TESCC nests and then metastatic lymph nodes, a trend of homoplasmic D310 mutation (10.6, 25.8, 31.4%; p=0.023), an ever increase of mtDNA copy ratios (0.892, 1.128, 1.183; p=0.018) and an elevated incidence of TP53 LOH (19.7, 34.8, 37.1%; p=0.010) were observed. From T1, T2, T3 to T4 TESCC, the incidence of TP53 LOH (12.5, 16.7, 34.8, 52.2%; p=0.011) was increased, in a stepwise fashion. Furthermore, we observed an association of TP53 LOH with an increased mtDNA copy ratio (p=0.022) and TP53 MI with heteroplasmic D310 mutation (p=0.069) in TESCC. Concurrent and associated microsatellite alterations in mtDNA and in TP53 in TESCC support the cancer clonal expansion theory and imply a possible relationship between the mitochondria and p53 in TESCC.

Wogonin triggers apoptosis in human osteosarcoma U-2 OS cells through the endoplasmic reticulum stress, mitochondrial dysfunction and caspase-3-dependent signaling pathways.

Wogonin (5,7-dihydroxy-8-methoxyflavone) is a flavone constituent of Scutellaria baicalensis with various beneficial biological activities and it has been shown to have tumor therapeutic potential in vitro and in vivo. The purpose of this study was to investigate the effects of wogonin in a human osteosarcoma cell line (U-2 OS). Results showed that a dose- and time-dependent reduction occurred in cell viability after exposure to wogonin in U-2 OS cells. Increasing the levels of reactive oxygen species (ROS) and Ca2+ but decreasing the levels of mitochondrial membrane potential (∆Ψm) were examined in wogonin-treated U-2 OS cells. Flow cytometric assay indicated that wogonin induced sub-G1 phase (apoptosis) and increased caspase-3 activity in examined cells. Wogonin-induced apoptosis in U-2 OS cells was also confirmed by 4',6-diamidino-2-phenylindole (DAPI) staining. Also, results from Western blotting indicated that wogonin increased the levels of Bad, Bax, cytochrome c, cleaved caspase-9, cleaved caspase-3, AIF, Endo G, Fas/CD95, caspase-8, GADD153, GRP78, ATF-6α, calpain 1, calpain 2 and caspase-4 then leading to cell apoptosis. In conclusion, wogonin induced ROS production and intracellular Ca2+, and altered the levels of anti- (Bcl-2) and pro- (Bad and Bax) apoptotic proteins. Wogonin-induced apoptosis in U-2 OS cells was through the activation of caspase-3. In conclusion, these are the first findings to show wogonin-induced cytotoxic effects through induction of apoptotic cell death and ER stress in U-2 OS cells. The potent in vitro antitumor activities suggest that wogonin could be developed for the treatment of human osteosarcoma in the future.

Terrorism in Taiwan, Republic of China.

The Republic of China on the island of Taiwan has experienced at least 20 terrorist events since 1979, including 13 aircraft hijackings and five bombings. Factors responsible for the relatively small burden of terrorism on Taiwan in the past include tight military control over political dissent until 1987, a warming relationship with the People's Republic of China in the 1990s, political inclusion of major internal cultural groups, geographic isolation, and a lack of other significant international enemies. Nevertheless, today Taiwan faces a new prospect of terrorism by adversaries of the United States and its allies and by an international paradigm shift in the types of weapons used by terrorists. National emergency management has been enhanced significantly since the Ji Ji earthquake in 1999, including the assignment of lead government agencies to the planning and preparedness for specific types of terrorist events involving nuclear, biological, and/or chemical releases. Other significant improvements at the operations level, include the establishment of two national disaster medical assistance teams, four urban search and rescue teams, 13 local disaster medical assistance teams, and eight chemical emergency response hospitals. Future challenges include improving the coordination of inter-agency response at the national level and the quantity and quality of local disaster response assets.