[A predictive model based on risk factors for early mortality in patients with newly diagnosed multiple myeloma]

目的

分析影响初治多发性骨髓瘤（NDMM）患者早期死亡（EM）的因素，建立其预测模型，以期识别EM风险。

方法

回顾性分析2009年5月至2017年1月吉林大学白求恩第一医院收治的275例NDMM患者，对6个月（EM6）、12个月（EM12）及24个月（EM24）内死亡患者初诊时基线特征进行单因素分析，并根据多因素分析结果建立EM的预测模型。

结果

本研究中EM6、EM12及EM24的发生率分别是5.5%、12.7%和30.2%；最常见的死亡原因为疾病复发/进展，在EM6、EM12及EM24中分别占60.0%、77.1%及84.3%。影响EM6的因素包括经白蛋白校正的血清钙（校正钙）>2.75 mmol/L和PLT<100×10⁹/L；影响EM12的因素包括年龄>75岁、国际分期系统（ISS） Ⅲ期、修订版国际分期系统（R-ISS） Ⅲ期、校正钙>2.75 mmol/L、血清肌酐>177 µmol/L、PLT<100×10⁹/L及骨髓浆细胞比例≥60%；影响EM24的因素中，除上述影响EM12的因素外，还包括男性和染色体核型1q+。多因素分析尚未发现EM6和EM12的独立预后因素。在EM24的多因素分析中，年龄>75岁、PLT<100×10⁹/L和染色体核型1q+是EM24的独立预后因素。根据Logistic回归系数赋分：年龄>75岁：1分；PLT<100×10⁹/L：2分；染色体核型1q+：1分，建立EM24预测模型，ROC曲线下面积为0.709（95%CI 0.626~0.793）。积分≥3分的患者24个月内死亡风险是0~2分患者的26倍，积分0~4分的NDMM患者中位总生存期分别为59、41、22、17.5及16个月（P<0.001）。

结论

年龄>75岁、PLT<100×10⁹/L和染色体核型1q+为EM24的独立预后因素，依据上述变量构建的EM24预测模型有助于识别EM风险和预测生存，具有较好标准度与区分度。

Comparison of mercury sulfides with mercury chloride and methylmercury on hepatic P450, phase-2 and transporter gene expression in mice

Zuotai (mainly β-HgS) and Zhusha (also called as cinnabar, mainly α-HgS) are used in traditional medicines in combination with herbs or even drugs in the treatment of various disorders, while mercury chloride (HgCl2) and methylmercury (MeHg) do not have known medical values but are highly toxic. This study aimed to compare the effects of mercury sulfides with HgCl2 and MeHg on hepatic drug processing gene expression. Mice were orally administrated with Zuotai (β-HgS, 30mg/kg), α-HgS (HgS, 30mg/kg), HgCl2 (33.6mg/kg), or MeHg (3.1mg/kg) for 7days, and the expression of genes related to phase-1 drug metabolism (P450), phase-2 conjugation, and phase-3 (transporters) genes were examined. The mercurials at the dose and duration used in the study did not have significant effects on the expression of cytochrome P450 1-4 family genes and the corresponding nuclear receptors, except for a slight increase in PPARα and Cyp4a10 by HgCl2. The expressions of UDP-glucuronosyltransferase and sulfotransferase were increased by HgCl2 and MeHg, but not by Zuotai and HgS. HgCl2 decreased the expression of organic anion transporter (Oatp1a1), but increased Oatp1a4. Both HgCl2 and MeHg increased the expression of multidrug resistance-associated protein genes (Mrp1, Mrp2, Mrp3, and Mrp4). Zuotai and HgS had little effects on these transporter genes. In conclusion, Zuotai and HgS are different from HgCl2 and MeHg in hepatic drug processing gene expression; suggesting that chemical forms of mercury not only affect their disposition and toxicity, but also affect their effects on the expression of hepatic drug processing genes.

[Filling blood vessels with latex and its application]

The purpose of this study is to find out the better conditions for filling blood vessels of the body with latex. We test it on 500 bodies. Our data show that the temperature for storing the latex, filling positions, the wash of blood vessels prior to filling and filling pressure are all important in this process. A good filling increases elasticity of vessels, makes vessels stronger and facilitates dissection of vessel. It is of importance in the study of cardiovascular system.

Multiple exon screening using restriction endonuclease fingerprinting (REF): detection of six novel mutations in the L1 cell adhesion molecule (L1CAM) gene

Restriction endonuclease fingerprinting (REF) has been utilized to screen 19 of the 28 exons in the L1CAM gene using only 5 PCR reactions. The clustered exons were amplified and the PCR products were subjected to endonuclease digestion and subsequent gel electrophoresis to produce a highly informative fingerprint for each PCR product. An alteration in the fingerprint, when compared to a control, determined the specific DNA fragment containing the mutation. Sequencing of the corresponding exon and flanking region was done to determine the precise location of the mutation. Using this method we have identified 6 novel mutations in the L1CAM gene in 5 patients with X-linked hydrocephalus and 2 patients with MASA. One of the mutations was common to both a patient with HSAS and a patient with MASA. The utilization of REF will allow for easier and quicker detection of mutations in the L1CAM gene. This method should be applicable for screening other genes with multiple, clustered exons.

The site of a missense mutation in the extracellular Ig or FN domains of L1CAM influences infant mortality and the severity of X linked hydrocephalus

The L1 cell adhesion molecule (L1CAM) plays an important role in axon growth, fasciculation, and neural migration. Mutations in the L1CAM gene produce a phenotype characterised by X linked hydrocephalus, mental retardation, spastic paraplegia, adducted thumbs, and agenesis of the corpus callosum. We have conducted a detailed analysis of the phenotypic effects of missense mutations in the extracellular portion of L1CAM, following a study that differentiated between "key" amino acid residues critical for maintaining the conformation of the extracellular immunoglobulin type C-like (Ig) or fibronectin type III-like (FN) domains and surface residues of less certain significance. We have analysed the data from 71 published cases and seven patients whose mutations were detected in our laboratory to determine if the site of a missense mutation in the Ig or FN domains correlated with the severity of hydrocephalus, presence of adducted thumbs, or survival past infancy. Mutations affecting the key residues in either type of domain were more likely to produce a phenotype with severe hydrocephalus, adducted thumbs, and lifespan less than one year than were mutations affecting surface residues. In addition, mutations affecting the FN domains were more likely than those affecting Ig domains to produce a phenotype with severe hydrocephalus, with less certain effects on adducted thumbs and lifespan. Mutations in key residues of the FN domains were particularly deleterious to infant survival. These data provide information that may be useful in predicting some aspects of the phenotypic effects of certain L1CAM mutations.

A silent mutation, C924T (G308G), in the L1CAM gene results in X linked hydrocephalus (HSAS)

The L1 cell adhesion molecule (L1CAM) is a neuronal gene involved in the development of the nervous system. Mutations in L1CAM are known to cause several clinically overlapping X linked mental retardation conditions: X linked hydrocephalus (HSAS), MASA syndrome (mental retardation, aphasia, shuffling gait, adducted thumbs), spastic paraplegia type I (SPG1), and X linked agenesis of the corpus callosum (ACC). In an analysis of a family with HSAS, we identified a C-->T transition (C924T) in exon 8 that was initially thought to have no effect on the protein sequence as the alteration affected the third base of a codon (G308G). Extensive analysis of the other 27 exons showed no other alteration. A review of the sequence surrounding position 924 indicated that the C-->T transition created a potential 5' splice site consensus sequence, which would result in an in frame deletion of 69 bp from exon 8 and 23 amino acids of the L1CAM protein. RT-PCR of the RNA from an affected male fetus and subsequent sequence analysis confirmed the use of the new splice site. This is the first report of a silent nucleotide substitution in L1CAM giving rise to an alteration at the protein level. Furthermore, it shows that as mutation analysis plays an ever more important role in human genetics, the identification of a synonymous base change should not be routinely discounted as a neutral polymorphism.

Regional localization of 725 human chromosome 7-specific yeast artificial chromosome clones

Toward the construction of a complete physical map of human chromosome 7, we have localized 725 YAC clones to cytogenetically defined regions using fluorescence in situ hybridization (FISH) and by screening with DNA markers of known chromosomal locations. These chromosome 7-specific YAC clones are part of a library constructed with DNA isolated from monochromosomal 7 human-hamster somatic cell hybrid lines. The FISH mapping for 575 clones was accomplished by using "Alu-PCR" amplified YAC DNA against metaphase chromosome spreads made from a monochromosomal 7 human-mouse somatic cell hybrid line. Hybridization- or PCR-based screening of previously mapped DNA markers was performed for the mapping of 221 YAC clones. There was excellent correlation between the map locations obtained for the 71 YACs localized with both methods. All of the regionally localized YAC clones are valuable reagents for mapping and identification of disease genes on human chromosome 7.