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Betel quid (BQ) chewing is a common oral habit in South Asia and Taiwan. BQ consumption may increase the risk of oral squamous cell carcinoma (OSCC), oral submucous fibrosis (OSF), and periodontitis as well as systemic diseases (atherosclerosis, hypertension, etc.). However, little is known about the toxic effect of BQ components on endothelial cells that play important roles for angiogenesis, carcinogenesis, tissue fibrosis, and cardiovascular diseases. EAhy 926 (EAHY) endothelial cells were exposed to arecoline, a major BQ alkaloid, for various time periods. Cytotoxicity was estimated by 3-(4, 5- dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide assay. The cell cycle distribution of EAHY cells residing in sub-G0/G1, G0/G1, S-, and G2/M phases was analyzed by propidium iodide staining of cellular DNA content and flow cytometry. Some EAHY cells retracted, became round-shaped in appearance, and even detached from the culture plate after exposure to higher concentrations of arecoline (> 0.4 mM). At concentrations of 0.4 and 0.8 mM, arecoline induced significant cytotoxicity to EAHY cells. At similar concentrations, arecoline induced G2/M cell cycle arrest and increased sub-G0/G1 population, a hallmark of apoptosis. Interestingly, prolonged exposure to arecoline (0.1 mM) for 12 and 21 days significantly suppressed the proliferation of EAHY cells, whereas EAHY cells showed adaptation and survived when exposed to 0.05 mM arecoline. These results suggest that BQ components may contribute to the pathogenesis of OSF and BQ chewing-related cardiovascular diseases via toxicity to oral or systemic endothelial cells, leading to impairment of vascular function. During BQ chewing, endothelial damage may be induced by areca nut components and associate with the pathogenesis of OSF, periodontitis, and cardiovascular diseases.  相似文献   
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MIDA boronates are among the most useful reagents for the Suzuki–Miyaura reaction. This chemistry typically generates new bonds between two aromatic rings, thereby restricting access to important areas of chemical space. Here we demonstrate the coupling of MIDA boronates to allylic electrophiles, including a new synthesis of the well-known COX inhibitor ibuprofen.

Here we demonstrate the coupling of MIDA boronates to allylic electrophiles, including a new synthesis of the well-known COX inhibitor ibuprofen.  相似文献   
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Background

Incidental findings of gallbladder cancer (GBCA) have dramatically increased as an initial presentation of the disease because of the expansion of laparoscopic cholecystectomy. However, the optimal management of T2 GBCA remains at issue.

Methods

We compared our 10-year experience with the consensus surgical strategy for T2 GBCA. Between January 2000 and December 2009, 70 patients at Severance Hospital, Yonsei University Health System, Seoul, Korea, underwent surgical treatment for GBCA stage T2. The medical records of 70 patients with T2 GBCA were retrospectively reviewed.

Results

Radical cholecystectomy was performed on only 32 (45.8 %) patients. In patients with T2 GBCA and positive lymph nodes (LN), the overall survival rate between cholecystectomy with LN dissection and radical cholecystectomy did not show a significant difference. Twenty patients experienced recurrence during the follow-up period. Among the 11 patients who underwent cholecystectomy with liver resection, only 2 (18.2 %) patients had an intrahepatic recurrence. Of the 9 patients who underwent cholecystectomy without liver resection, 3 (33.3 %) patients had an intrahepatic recurrence. However, recurrences at the gallbladder bed occurred only in one and two patients, respectively, and were not significantly different between the two groups.

Conclusions

There was a large gap between clinical practice and treatment guidelines. Though relatively few patients enrolled in this study experienced recurrence, cholecystectomy and LN dissection without liver resection showed similar survival and recurrence patterns compared with those of radical cholecystectomy. To improve consistency between clinical practice and consensus guidelines, the role of limited resection for T2 lesions needs further evaluation.  相似文献   
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PurposeTo investigate the safety and effectiveness of preoperative prostatic artery embolization (PAE) in relation to decrease in hemoglobin level, requirement for blood transfusion, length of hospitalization, and procedure-related complications.Materials and MethodsTen consecutive patients who underwent surgery after preoperative PAE were identified from May 2017 to October 2018 (embolization group: holmium-laser enucleation of the prostate [HoLEP] in 6 patients and robotic simple prostatectomy in 4 patients, mean age 72.9 ± 8.7 years, mean prostatic volume 106.5 ± 22.0 mL). For comparison, consecutive patients with a large prostatic volume (≥70 mL) who underwent surgery without preoperative PAE during the same period were enrolled (nonembolization group: HoLEP in 9 patients and robotic simple prostatectomy in 1 patients, mean age 71.2 ± 5.7 years, mean prostatic volume 87.8 ± 26.7 mL).ResultsPAE was technically successful in 90% of patients (9/10). The median interval between PAE and surgery was 2 days. The mean hemoglobin reduction was lower (1.40 ± 0.92 g/dL vs 3.07 ± 1.50 g/dL; P = .008) and the median length of hospitalization was shorter (8.5 days vs 11 days; P = .039) in the embolization group than the nonembolization group. The operating time (mean for HoLEP 146 ± 38 min vs 179 ± 59 min [P = .248], mean for robotic simple prostatectomy 223 ± 32 min vs 354 min) and number of blood transfusion (1 patient vs 2 patients; P = .392) were not significantly different between the 2 groups. None of the patients developed any complications except bleeding requiring transfusion.ConclusionsPreoperative PAE is safe and may reduce blood loss during prostate surgery.  相似文献   
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