Logistic回归和ROC曲线分析多种肿瘤标志物在结直肠癌中的诊断价值

目的:应用Logistic回归和ROC曲线探讨CEA、CA199及CA50在结直肠癌诊断中的应用价值.方法:结直肠癌患者75例,良性结直肠病患者35例,正常人49例,分别应用化学发光免疫分析测定CEA,电化学发光免疫分析测定CA199,免疫放射分析测定CA50,通过ROC曲线分析CEA、CA199、CA50及各种Logistic回归结果的ROC曲线下面积(AUC).结果:结直肠癌-良性结直肠病中,CA50的AUC要高于CA199的AUC,而CEA、CA50两项联合诊断结直肠癌的AUC(0.875)要高于CEA、CA199、CA50三项联合诊断的AUC(0.604),且CEA、CA50两项联检诊断的AUC高于CEA、CA199或CA50任意单一检查的AUC.在结直肠癌-正常对照组中,三项肿瘤标志物联检的AUC(0.866)均高于三项肿瘤标志物单一检查的AUC,无论在结直肠癌-正常对照组中还是结直肠癌-良性结直肠病中CEA的AUC都高要于CA199或CA50.结论:CEA在诊断结直肠癌有一定的临床应用价值,CA50联合CEA检测可为临床鉴别良恶性结直肠病提供有效的参考,而CEA、CA199及CA50三者联检对鉴别良恶性结直肠病的意义不大.作为一种统计手段,Logistic回归可改善诊断的灵敏度和特异性.     

THE EXPLORATION ON APPLIED VALUE OF BA IN DIAGNOSIS OF TIA

目的:探讨脑电地形图在短暂性脑缺血发作诊断中的应用价值.方法:在68例短暂性脑缺血发作患者中,进行了脑电地形图检查.结果:在67(98.52%)例患者中脑电地形图是异常的.40(58.82%)的患者脑电地形图在θ或δ频段显示高功率阴影,在α频段显示低功率阴影.14(20.59%)例患者在α频段显示低功率阴影.12(17.65%)例患者在θ或δ频段显示高功率阴影.1(1.47%)例患者在β频段显示低功率阴影.1(1.47%)例患者正常.结论:脑电地形图在短暂性脑缺血发作的临床诊断中具有重要意义.     

苍白球损毁术中微电极的位置识别方法

在治疗帕金森病的苍白球损毁外科手术中,微电极在苍白球中的位置只能通过分析微电极测量的细胞放电特征,依靠主观经验判定。我们以临床微电极信号为基础,利用峰峰时间间隔因子,提出了客观定量的识别微电极位置的方法。该方法能有效的识别出沿微电极针道苍白球组织的变化以及针道是否偏离,识别结果与苍白球解剖结构和手术情况相吻合,此方法可用于临床手术导向。     

基于射线距离误差的三维医学图像分割的新型评价方法

三维医学图像的分割是计算机辅助诊断与治疗中至关重要的技术。由于现有的三维医学图像分割算法种类繁多且性能各异,对各种分割算法性能公正直观的评价显得尤为重要。我们在对现有常用评价方法做出综合的比较后,提出了一种基于局域距离误差的综合、直观的三维图像分割的新型评价方法,并详细描述了该评价方法中局域误差和全局精确度的评价法。最后,利用这种新型的评价方法对三种常用的分割算法(Fast Marching,Morpholo-gical Reconstruction and Watershed)及一种笔者提出的新型Hybrid算法进行评价,此新型分割算法也在文中作了简要介绍。通过实验,可以验证新的评价方法能够更加科学、直观地对各种三维医学图像分割算法进行评价。     

Acute phase response in zebrafish upon Aeromonas salmonicida and Staphylococcus aureus infection: striking similarities and obvious differences with mammals

Zebrafish has emerged as a valuable model for immunological studies. However, little is known about the overall picture of its immune response to infectious pathogens. Here we present the first systematic study of its immune response to Aeromonas salmonicida and Staphylococcus aureus, a Gram-negative and a Gram-positive bacteria, respectively. Genes induced upon infection were identified with suppression subtractive hybridization, with many of them encoding acute phase proteins (APPs). When compared with mammals, striking similarities and obvious differences have been observed. Both similar APPs (SAA, hepcidin and haptoglobin, etc.) and a similar system for the induction of APPs (which involves the TLRs, pro-inflammatory cytokines and C/EBPs) were identified, implying evolutionary conserved mechanisms among fish and mammals. Some novel APPs were also discovered, suggesting different immune strategies adopted by fish species. Among which, LECT2 was induced by up to 1000-fold upon infection, shedding new lights on the function of this gene. Our results constitute the first demonstration of a similar while different immune response in zebrafish and open new avenues for the investigation of evolutionary conserved and fish specific mechanisms of innate immunity.     

Meiotic segregation analysis in spermatozoa of pericentric inversion carriers using fluorescence in-situ hybridization

BACKGROUND: Pericentric inversions are structural chromosomal abnormalities resulting from two breaks, one on either side of the centromere, within the same chromosome, followed by 180 degrees rotation and reunion of the inverted segment. They can perturb spermatogenesis and lead to the production of unbalanced gametes through the formation of an inversion loop. METHODS: We report here the analysis of the meiotic segregation in spermatozoa from six pericentric inversion carriers by multicolour fluorescence in-situ hybridization (FISH) and review the literature. RESULTS: The frequencies of the non-recombinant products (inversion or normal chromosomes) were 80% for the inv(20), 91.41% for the inv(12), 99.43% for the inv(2), 68.12% for the inv(1), 97% for the inv(8)(p12q21) and 60.94% for the inv(8)(p12q24.1). The meiotic segregation of 20 pericentric inversions (including ours) is now available. The frequency of unbalanced spermatozoa varies from 0 to 37.85%. The probability of a crossover within the inverted segment is affected by the chromosome and region involved, the length of the inverted segment and the location of the breakpoints. CONCLUSIONS: No recombinant chromosomes were produced when the inverted segment involved <30% of the chromosome length (independent of the size of the inverted segment). Between 30 and 50%, few recombinant chromosomes were produced, inducing a slightly increased risk of aneusomy of recombination in the offspring. The risk of aneusomy became very important when the inverted segment was >50% of the chromosome length. Studies on spermatozoa from inversion carriers help in the comprehension of the mechanisms of meiotic segregation. They should be integrated in the genetic exploration of the infertile men to give them a personalized risk assessment of unbalanced spermatozoa.     

Evolutionary dynamics of transposable elements in the short-tailed opossum Monodelphis domestica

The genome of the gray short-tailed opossum Monodelphis domestica is notable for its large size ( approximately 3.6 Gb). We characterized nearly 500 families of interspersed repeats from the Monodelphis. They cover approximately 52% of the genome, higher than in any other amniotic lineage studied to date, and may account for the unusually large genome size. In comparison to other mammals, Monodelphis is significantly rich in non-LTR retrotransposons from the LINE-1, CR1, and RTE families, with >29% of the genome sequence comprised of copies of these elements. Monodelphis has at least four families of RTE, and we report support for horizontal transfer of this non-LTR retrotransposon. In addition to short interspersed elements (SINEs) mobilized by L1, we found several families of SINEs that appear to use RTE elements for mobilization. In contrast to L1-mobilized SINEs, the RTE-mobilized SINEs in Monodelphis appear to shift from G+C-rich to G+C-low regions with time. Endogenous retroviruses have colonized approximately 10% of the opossum genome. We found that their density is enhanced in centromeric and/or telomeric regions of most Monodelphis chromosomes. We identified 83 new families of ancient repeats that are highly conserved across amniotic lineages, including 14 LINE-derived repeats; and a novel SINE element, MER131, that may have been exapted as a highly conserved functional noncoding RNA, and whose emergence dates back to approximately 300 million years ago. Many of these conserved repeats are also present in human, and are highly over-represented in predicted cis-regulatory modules. Seventy-six of the 83 families are present in chicken in addition to mammals.     

Endoscopic ultrasound-guided fine-needle aspiration of undifferentiated carcinoma with osteoclast-like giant cells of the pancreas: a report of 2 cases with literature review

Undifferentiated carcinoma with osteoclast-like giant cells of the pancreas is rare. Histologically it mimics the giant cell tumor of the bone and may be associated with a ductal adenocarcinoma. We recently encountered two such cases, both of which were biopsied by EUS-guided FNA. Abundant multinucleated osteoclast-like giant cells and many uniform mononuclear cells were present in case 1 so that the diagnosis was made. In case 2, many mononuclear tumor cells with vacuolated and basophilic cytoplasm were present, and rare osteoclast-like giant cells were seen. A diagnosis of adenocarcinoma was made. In both cases, no conspicuous nuclear pleomorphism was noted in the mononuclear cells or the multinucleated giant cells. The histology of case 2 revealed a pure undifferentiated carcinoma with osteoclast-like giant cells. In addition, a liver biopsy revealed globular amyloidosis. To our knowledge, this is the first report of pancreatic undifferentiated carcinoma with osteoclast-like giant cells sampled by EUS-guided FNA and the first case of hepatic globular amyloidosis associated with this tumor.     

Chronic high-inspired CO2 decreases excitability of mouse hippocampal neurons

To examine the effect of chronically elevated CO(2) on excitability and function of neurons, we exposed mice to 8 and 12% CO(2) for 4 wk (starting at 2 days of age), and examined the properties of freshly dissociated hippocampal neurons obtained from slices. Chronic CO(2)-treated neurons (CC) had a similar input resistance (R(m)) and resting membrane potential (V(m)) as control (CON). Although treatment with 8% CO(2) did not change the rheobase (64 +/- 11 pA, n = 9 vs. 47 +/- 12 pA, n = 8 for CC 8% vs. CON; means +/- SE), 12% CO(2) treatment increased it significantly (73 +/- 8 pA, n = 9, P = 0.05). Furthermore, the 12% CO(2) but not the 8% CO(2) treatment decreased the Na(+) channel current density (244 +/- 36 pA/pF, n = 17, vs. 436 +/- 56 pA/pF, n = 18, for CC vs. CON, P = 0.005). Recovery from inactivation was also lowered by 12% but not 8% CO(2). Other gating properties of Na(+) current, such as voltage-conductance curve, steady-state inactivation, and time constant for deactivation, were not modified by either treatment. Western blot analysis showed that the expression of Na(+) channel types I-III was not changed by 8% CO(2) treatment, but their expression was significantly decreased by 20-30% (P = 0.03) by the 12% treatment. We conclude from these data and others that neuronal excitability and Na(+) channel expression depend on the duration and level of CO(2) exposure and maturational changes occur in early life regarding neuronal responsiveness to CO(2).     

Using mental tasks transitions detection to improve spontaneous mental activity classification

This paper presents an algorithm based on canonical variates transformation (CVT) and distance based discriminant analysis (DBDA) combined with a mental tasks transitions detector (MTTD) to classify spontaneous mental activities in order to operate a brain-computer interface working under an asynchronous protocol. The algorithm won the BCI Competition III--Data Set V: Multiclass Problem, Continuous EEG--achieving an averaged classification accuracy over three subjects of 68.65% (79.60, 70.31 and 56.02%, respectively) in a three-class problem.