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81.
Translocations involving MYC are highly characteristic for Burkitt lymphoma (BL). BCL2 expression has also been found previously in about 10 to 20% of BL cases, and BCL2 translocation is a major mechanism for the deregulation of BCL2 expression in non‐Hodgkin lymphomas. However, we know little about the incidence of MYC/BCL2 double‐hit (DH) in BL. We examined BL cases to determine how frequently they contained BCL2 translocations in combination with MYC translocations using fluorescence in situ hybridization. We also determined the effect of BCL2 expression on clinical outcomes of BL. BCL2 translocations were detected in 3.5% (2/57 cases) of the cases, and BCL2 expression was detected in 33%. Two cases with BCL2 translocation also showed BCL2 expression. The incidence of BCL2 expression was significantly higher in patients 16 years of age and older (46%) than in patients under 16 years of age (6%). Among patients 16 years of age and older, we did not detect significant differences in overall survival with respect to BCL2 expression status. In conclusion, BCL2 translocation is a rare cytogenetic abnormality in BL, and BL probably accounts for only a small fraction of MYC/BCL2 DH lymphomas. BCL2 expression in BL is probably not associated with BCL2 translocations.  相似文献   
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It has been hypothesized that respiration defects caused by accumulation of pathogenic mitochondrial DNA (mtDNA) mutations and the resultant overproduction of reactive oxygen species (ROS) or lactates are responsible for aging and age-associated disorders, including diabetes and tumor development. However, there is no direct evidence to prove the involvement of mtDNA mutations in these processes, because it is difficult to exclude the possible involvement of nuclear DNA mutations. Our previous studies resolved this issue by using an mtDNA exchange technology and showed that a G13997A mtDNA mutation found in mouse tumor cells induces metastasis via ROS overproduction. Here, using transmitochondrial mice (mito-mice), which we had generated previously by introducing G13997A mtDNA from mouse tumor cells into mouse embryonic stem cells, we provide convincing evidence supporting part of the abovementioned hypothesis by showing that G13997A mtDNA regulates diabetes development, lymphoma formation, and metastasis--but not aging--in this model.  相似文献   
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Purpose

To explore the possibility of targeted biopsy (TBx) using transrectal ultrasound (US) with perflubutane microbubbles, we studied the findings of different cancerous tissue imaging modalities and evaluated needle biopsy in prostate cancer (PCa) using contrast-enhanced US (CEUS) in a multicenter clinical trial.

Methods

Seventy-one patients undergoing prostate biopsy received intravenous injection of perflubutane microbubbles (Sonazoid®). We evaluated and compared images obtained by CEUS. The safety observation period was 2 days after contrast administration.

Results

Among the 30 patients with cancer, one or more sites with findings suggestive of cancer in CEUS were detected in 23 patients (32.4%) by TBx. Although 22 patients had positive cores of cancer by systematic biopsy (SBx), 8 patients had positive cores of cancer in TBx alone (11.3%). There was a significant difference in cancer detection rate by TBx between two cohorts with PSA < 10 ng/mL (22.9%) and PSA ≥ 10 ng/mL (52.2%) (P < 0.02). Close observation of various CEUS findings with Sonazoid® enabled targeting of cancerous areas, and consequently, a significant difference (P < 0.05) in the detection rate of cancer was recognized in the transition zone (TZ): SBx; 21/120 (17.5%) and TBx; 17/55 (30.9%). The incidence of adverse events was 6.7% and that of adverse reactions was 4%.

Conclusions

CEUS with Sonazoid® improved the detection rate of PCa by visualizing cancerous lesions. More detailed examination of CEUS images provided efficient characterization especially in the TZ area. TBx according to this procedure is expected to enable a lower number of biopsies and more accurate diagnosis of PCa.  相似文献   
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Purpose

Nephron sparing surgery is an effective surgical option in patients with renal cell carcinoma. Laparoscopic partial nephrectomy involves clamping and unclamping techniques of the renal vasculature. This study compared the postoperative renal function of partial nephrectomy using an estimation of the glomerular filtration rate (eGFR) for a Japanese population in 3 procedures; open partial nephrectomy in cold ischemia (OPN), laparoscopic partial nephrectomy in warm ischemia (LPN), and microwave coagulation using laparoscopic partial nephrectomy without ischemia (MLPN).

Materials and Methods

A total of 57 patients underwent partial nephrectomy in Yokohama City University Hospital from July 2002 to July 2008. 18 of these patients underwent OPN, 17 patients received MLPN, and 22 patients had LPN. The renal function evaluation included eGFR, as recommended by The Japanese Society of Nephrology.

Results

There was no significant difference between the 3 groups in the reduction of eGFR. eGFR loss in the OPN group was significantly higher in patients that experienced over 20 minutes of ischemia time. eGFR loss in LPN group was significantly higher in patients that experienced over 30 minutes of ischemia time.

Conclusion

This study showed that all 3 procedures for small renal tumor resection were safe and effective for preserving postoperative renal function.Key Words: eGFR, Partial nephrectomy, Renal function, Laparoscopic partial nephrectomy  相似文献   
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ABSTRACT

Objective: Adult patients with ischemic moyamoya disease (MMD) who receive treatment with antiplatelet drugs reportedly show improvements in neuropsychological test scores after around 2 years. The purpose of the present study subanalyzing the same patient cohort used in a previous study was to determine which antiplatelet drug, clopidogrel or cilostazol, results in better improvement of cognitive function among non-surgical adult patients showing ischemic MMD without severe hemodynamic compromise.

Methods: Sixty-six patients without cerebral misery perfusion on 15O gas positron emission tomography were treated with pharmacotherapy alone. Patients ≥50 years old and <50 years old initially received clopidogrel and cilostazol, respectively. Any patient suffering side effects of the antiplatelet drug switched to the other antiplatelet drug. Neuropsychological tests were performed at study entry and at the end of the 2-year follow-up, and differences in each neuropsychological test score between the two time points (second test score – first test score) were calculated and defined as Δ scores.

Results: Among the five neuropsychological tests, Δ scores for two tests were significantly greater in patients treated with cilostazol (n = 36) than in those treated with clopidogrel (n = 30), and Δ scores of the remaining three tests did not differ between patient groups. Based on Δ scores, 15 patients (23%) were defined as showing interval cognitive improvement. On multivariate analysis, cilostazol administration (95% confidence interval, 1.19–193.98; P = 0.0361) represented an independent predictor of interval cognitive improvement.

Conclusions: Cilostazol may improve cognition better than clopidogrel in non-surgical adult patients with ischemic MMD.  相似文献   
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