Patterns of cancer distribution in a medical center among adolescents 14 to 17 years of age for the period 1995 to 2001.

BACKGROUND AND PURPOSE: There are limited data on the pattern of cancer distribution among adolescents in Taiwan. This study evaluated the characteristics of these rare cancers in a medical center. METHODS: Analyses of the characteristics of malignant neoplasms for patients aged 14 to 17 years at diagnosis were performed for all cases recorded in the tumor registry of Chang Gung Memorial Hospital (CGMH) at Linkou for the period 1995 to 2001. All eligible tumors were categorized in 1 of 12 diagnostic groups according to the scheme of the International Classification of Childhood Cancer (ICCC). Relative frequencies, age, and gender variations and the characteristics of tumor types were analyzed. RESULTS: Cancer was diagnosed in 320 adolescents during the study period. The male/female ratio was 1.17. Leukemia was the leading diagnostic group. The frequency of carcinomas increased with age and was highest among 17-year-olds. In this age group, non-rhabdomyosarcoma soft tissue sarcoma/primitive neuroectodermal tumor (non-RMS STS/PNET), thyroid carcinoma (CA) and ovarian germ cell tumor (GCT) were the 3 most common solid tumors; the embryonal malignancies were rare. Tumors with the greatest male predominance were intracranial GCT (91%), nasopharyngeal CA (87.5%), osteosarcoma (84.6%), and colorectal CA (75%). Tumors with the greatest female predominance were thyroid CA (78.3%), gonadal GCT (75%), and non-RMS/PNET (56.5%). Hepatocellular CA comprised 9.4% of all carcinomas. CONCLUSIONS: The relative frequency and the distribution of histology subtypes among adolescents were between those of childhood and adult cancers. There were marked variations in tumor occurrence between genders and among different ages.     

Functional correlates of Doppler flow study of the female urethral vasculature.

OBJECTIVES: To examine the effect of individual patient factors (age, parity, body mass index, menstrual cycle, menopause, hormone replacement therapy, bladder neck position and urethral mobility) on the appearance of Doppler flow in urethral vessels, to investigate the association between the Doppler flow parameters and intrinsic urethral function, storage and voiding, and to explore differences in the urethral vasculature between subjects with and without urodynamic stress incontinence (USI). METHODS: Over a 4-year period we prospectively performed imaging studies in 355 women, including 244 who denied any lower urinary tract symptoms within the previous 3 months (Group A) and 111 who had had lower urinary tract symptoms (Group B). Studies included morphologic assessment and Doppler flow investigation of the lower urinary tract. Vascular flow velocity and vessel density in the urethral vasculature were measured. For women in Group B, multichannel urodynamic studies were also performed. RESULTS: The urethral vasculature has five main branches of vessels. Their appearance was not affected by the menstrual cycle or menopause except for those of the anterior vaginal vessel and anterior branch of the middle urethral vessel. Other than that of the posterior urethral vessel, in which there was a correlation with parity, the resistance index (RI) was not affected by individual patient factors. However, there was a correlation between the vascular index (VI) and individual factors such as age (r = -0.336, P = 0.002), body mass index (r = -0.287, P = 0.028), menopause (r = -0.402, P < 0.001), and hormone replacement therapy (r = 0.392, P = 0.027). Only the VI and RI of the posterior urethral vessel correlated significantly with the urethral pressure profile. In subjects with lower urinary tract symptoms, the appearance of the urethral vasculature on power Doppler imaging and the corresponding RI and VI values were not correlated with objective evidence of USI. CONCLUSION: Patient factors may affect specific Doppler flow parameters of the urethral vasculature, which are related to intrinsic resting urethral closure. There is no difference in the appearance of the urethral vasculature in subjects with or without USI.     

兔视网膜方向选择性神经节细胞树突的独特分枝模式及其生理意义

本实验研究了兔视网膜中的方向选择性神经节细胞 (direction selective retinal ganglion cells,DS cells)树突野的分枝模式。测量了视网膜中方向选择性神经节细胞和作为经典分枝模式神经元代表的α神经节细胞的树突直径。发现 ,方向选择性神经节细胞的树突在分枝后直径达到 0 .5 μm,进一步分枝树突直径仍保持在 0 .5 μm左右 ,这样 ,在方向选择性神经节细胞树突野中大多数树突直径在 0 .5μm左右。而作为经典分枝模式神经元代表的α神经元的树突每次分枝后都逐级变细 ,最终直径达到 0 .5μm左右 ,这样 ,α神经节细胞的树突直径大部分都大于 0 .5μm。我们应用程序“NEU RON”对在两种神经元模型中 ,抑制点落于兴奋点与胞体之间 (proximal)和抑制点不落于兴奋点与胞体之间 (distal)这两种情况进行模拟。我们发现 ,当抑制点不落于兴奋点与胞体之间时 ,在方向选择性神经节细胞的树突分枝模型中 ,抑制效果更强。那么 ,将使得方向选择性神经节细胞对抑制点落于兴奋点和胞体之间的要求变得不是那么迫切。所以 ,方向选择性神经节细胞的这种独特分枝模式 ,也许可以避免或至少减轻其在发育中可能会产生的连线的复杂性。并且 ,我们对得出的结论进行了电路分析 ,对方向选择性神经节细胞这种独特的分枝模式具有的?     

自体腹白线片修补十二指肠溃疡穿孔(附13例报告)

目的探讨用游离自体腹白线片修补急性十二指肠溃疡穿孔的应用价值。方法从2006年1月至2006年7月对13例用自体腹白线片修补急性十二指肠溃疡穿孔的病人的临床资料和随访情况进行回顾性分析,其中2例穿孔大于2cm2,平均手术时间60分钟,平均失血量20ml,平均住院天数9±1天。结果游离自体腹白线片修补急性十二指肠溃疡穿孔13例均痊愈出院。随访15天至6个月,无手术并发症。结论本方法操作较简单、安全、效果好,其适应症广,是一种可行的新方法。     

A comparative study of using comet assay and gammaH2AX foci formation in the detection of N-methyl-N'-nitro-N-nitrosoguanidine-induced DNA damage.

Comet assay is a useful technique in the detection of DNA damages, particularly DNA strand breaks; and it has been utilized to show that a potent carcinogen N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), can induce such damages. Recently, gammaH2AX foci formation has been suggested as another sensitive way to detect DNA double strand breaks (DSBs). However, there is no systematic comparison being conducted to evaluate the consistency of these two methods. Using MNNG as a model chemical, the sensitivity of neutral comet assay and gammaH2AX foci formation in detecting MNNG-induced damage was studied. It was found that at concentrations of 0.1 and 1 microg/ml, both methods can detect MNNG-induced damage in human amnion FL cells. However, at 0.1 microg/ml, comet assay revealed more percentage of cells with DNA damage than gammaH2AX fluorescence revealed. On the other hand, while gammaH2AX foci were readily formed at very early times by 10 microg/ml MNNG treatment, neutral comet assay did not detect any significant DNA damage at the same time points. In addition, 10 microg/ml MNNG induced a distinct whole nuclei staining pattern of gammaH2AX, a type of DNA damage which was not detected by neutral comet assay but could be detected by alkaline comet assay. Therefore, gammaH2AX may be used as a sensitive indicator for DNA damage.