Partial trisomy 7q and monosomy 13q in a child with disorder of sex development: Phenotypic and genotypic findings

Terminal 7q duplication and terminal 13q deletion are two conditions with variable phenotypes including microcephaly, thumb a-/hypoplasia, cortical dysplasia, microphtalmia, intellectual disability and dysmorphic features. We describe a boy born to a mother with a reciprocal t (7;13) who combines both a terminal 7q33-qter duplication and terminal 13q33-qter deletion through the inheritance of a derivative chromosome 13 (der (13)). The patient presented with developmental delay, facial and non-facial dysmorphic features, hypertonia, genital abnormality and skeletal malformation but no thumb a-/hypoplasia or microphtalmia. Knowing the exact breakpoints of his chromosomal aberrations using high resolution array CGH (aCGH) and comparison of his phenotypes with those of 24 and 59 previously published cases of 7q duplication and 13q deletion, respectively, allow us to further narrow the size of the proposed critical regions for microcephaly, thumb a-/hypoplasia and hypo/hypertonia on chromosome 13.     

Microarray analysis of microRNA expression in liver cancer tissues and normal control

Background

Recently, many studies have focused on microRNAs (miRNAs) expression profiling in liver cancer, due to the ability of these small RNAs to potently influence cellular behavior. In this study, to further investigate the relationship between them, the miRNA expression profiling of the cancer liver tissues and normal liver tissues were compared.

Methods

The datasets of miRNAs microarray in liver cancer and normal control were downloaded from Gene Expression Omnibus. Then the SOAP analysis was performed to identify the differentially expressed miRNAs.

Results

A total of 221 differentially expressed miRNAs were found. Five of them (including hsa-miR-15b, hsa-miR-1975, hsa-miR-199a-3p, hsa-miR-199b-3p and hsa-miR-421) were determined by t-test and may be involved in the pathogenesis of liver cancer.

Conclusion

There differentially expressed miRNAs may be potential molecular markers for liver cancer screening.     

Expanding the mutation spectrum for Fraser syndrome: Identification of a novel heterozygous deletion in FRAS1

Fraser syndrome (FS) is a rare autosomal recessive inherited disorder characterized by cryptophthalmos, laryngeal defects and oral clefting, mental retardation, syndactyly, and urogenital defects. To date, 250 patients have been described in the literature. Mutations in the FRAS1 gene on chromosome 4 have been identified in patients with Fraser syndrome. So far, 26 mutations have been identified, most of them are truncating mutations. The mutational spectrum includes nucleotide substitutions, splicing defects, a large insertion, and small deletions/insertions. Moreover, single heterozygous missense mutations in FRAS1 seem to be responsible for non-syndromic unilateral renal agenesis.     

Lubricating Properties of the Initial Salivary Pellicle — an AFM Study

The role of saliva in the oral cavity is manifold; an important function is to serve as lubricant between hard (enamel) and soft (mucosal) tissues. Intraoral lubrication is of crucial importance in order to maintain functions such as deglutition, mastication and the faculty of speech. A large number of people suffer from impaired salivary functions, displaying symptoms such as ‘dry mouth’. This results in a need for methods to assess the lubricating properties of both native saliva and potential artificial saliva formulations. Here, normal as well as lateral forces, acting between adsorbed salivary films, have been measured for the first time by means of colloidal probe atomic force microscopy (AFM). It was found that the presence of salivary pellicles between hard surfaces reduces the friction coefficient by a factor of 20. This reduction of friction is consistent with the long-range purely repulsive nature of the normal forces acting between the salivary films. The lubricating mechanism is presumably based on a full separation of the sliding surfaces by the salivary films. The friction between salivary films has been investigated at normal loads that cover the clinical jaw closing forces, and it can be concluded that the lubricating properties are maintained within this load interval. The present study indicates the usefulness of colloidal probe AFM, which offers a direct and quantitative measure of lubrication at a molecular level, in the study of biotribological phenomena. In particular, the results obtained here may have implications for the development of saliva substitutes.     

Aptamers: Molecules of great potential

Aptamers emerged over 20 years ago as a class of nucleic acids able to recognize specific targets. Today, aptamer-related studies constitute a large and important field of biotechnology. Functional oligonucleotides have proved to be a versatile tool in biomedical research due to the ease of synthesis, a wide range of potentially recognized molecular targets and the simplicity of selection. Similarly to antibodies, aptamers can be used to detect or isolate specific molecules, as well as to act as targeting and therapeutic agents. In this review we present different approaches to aptamer application in nanobiotechnology, diagnostics and medicine.     

1,8-Naphthalimide–Cu(ІІ) ensemble based turn-on fluorescent probe for the detection of thiols in organic aqueous media

A 1,8-naphthalimide–Cu(II) ensemble was rationally designed and synthesized as a new turn-on fluorescent probe utilizing the ‘chemosensing ensemble’ method for detections of thiols (Cys, Hcy and GSH) with high selectivity over other α-amino acids at pH 7.4 in organic aqueous media (EtOH/HEPES, v/v = 9:1). The recognition mechanism was attributed to the remove Cu(II) from the 1,8-naphthalimide–Cu(II) ensemble by thiols and the release of flurescence of ligand 1. Remarkable fluorescence enhancements were therefore observed in the sensing process of thiols by the 1,8-naphthalimide–Cu(II) ensemble. Furthermore, the 1,8-naphthalimide–Cu(II) ensemble was successfully applied to the fluorescence imaging of thiols in CHO cells with high sensitivity and selectivity.     

Anion Transport in Red Blood Cells II. Kinetics of Reversible Inhibition by Nitroaromatic Sulfonic Acids

The anion exchange system of human red blood cells is highly inhibited and specifically labeled by isothiocyano derivatives of benzene sulfonate (BS) or stilbene disulfonate (DS). To learn about the site of action of these irreversibly binding probes we studied the mechanism of inhibition of anion exchange by the reversibly binding analogs p-nitrobenzene sulfonic acid (pNBS) and 4,4′-dinitrostilbene-disulfonic acid (DNDS). In the absence of inhibitor, the self-exchange flux of sulfate (pH 7.4, 25°C) at high substrate concentration displayed self-inhibitory properties, indicating the existence of two anion binding sites: one a high-affinity transport site and the other a low-affinity modifier site whose occupancy by anions results in a noncompetitive inhibition of transport. The maximal sulfate exchange flux per unit area was J_A = (0.69 ± 0.11) × 10^-10 moles · min^-1 · cm^-2 and the Michaelis-Menten constants were for the transport site K_S = 41 ± 14 mM and for the modifier site K_S' = 653 ± 242 mM. The addition to cells of either pNBS at millimolar concentrations or DNDS at micromolar concentrations led to reversible inhibition of sulfate exchange (pH 7.4, 25°C). The relationship between inhibitor concentration and fractional inhibition was linear over the full range of pNBS or DNDS concentrations (Hill coefficient n ? 1), indicating a single site of inhibition for the two probes. The kinetics of sul- fate exchange in the presence of either inhibitor was compatible with that of competitive inhibition. Using various analytical techniques it was possible to determine that the sulfate trans- port site was the target for the action of the inhibitors. The in- hibitory constants (Ki j for the transport sites were 0.45 ± 0.10 PM for DNDS and 0.21 ± 0.07 mM for pNBS. From the similarities between reversibly and irreversibly binding BS and DS inhibitors in structures, chemical properties, modus oper- andi, stoichiometry of interaction with inhibitory sites, and relative inhibitory potencies, we concluded that the anion trans- port sites are also the sites of inhibition and of labeling of co- valent binding analogs of BS and DS.     

黄土山地苹果树树体不同方位液流速率分析

精准确定果园蒸腾耗水规律是进行果园水肥管理的基础.论文采用热扩散式边材液流茎流探针和微型自动气象站组成的测定系统,对陕北黄土山地苹果树树干液流及相关指标进行了连续观测,分析了不同方位探针树干液流速率的测定结果.结果表明:果树不同生长阶段,液流速率变化较大,白天蒸腾速率较大,蒸腾量占全天蒸腾量均在86.29％以上;不同方位探针测定结果差异明显,东、西向探针测定结果较为接近,南、北向测定结果差异较大;不同方位探针测定边材液流量与参考作物蒸散量的线性模型表明,东、西向探针测定液流量与参考作物蒸散量关系密切,决定系数分别达0.74和0.83,方差分析均方比分别为78.21和137.85,其相关性明显优于南、北方向;比较以水量平衡计算得出的苹果树耗水量,东、西向探针测定的苹果树蒸腾量与水量平衡计算结果较为接近,均方比分别达到14.11和14.57,显著性水平分别达到0.020和0.019,明显高于南北方向探针测定结果.测定苹果树液流量时,选择东面或西面安装液流计探针,可有效减小试验误差.     

猴免疫缺陷病毒（SIV）实时荧光定量PCR检测方法的建立

目的建立快速、敏感、特异的猴免疫缺陷病毒（SIV）TaqMan探针实时荧光定量PCR检测方法,对SIV病毒核酸进行定量检测。方法RT—PCR扩增SIVmac251保守gag基因序列796bp片段,进行TA克隆,构建标准品质粒pMD—SIVgag。通过对SIV定量外标准品的定量分析,优化反应体系,检测TaqMan探针实时荧光定量PCR方法的灵敏度、特异性和重复性。结果所建立的SIVQPCR检测方法,质粒DNA模板在10’～10。拷贝之间表现较好线性和相关性,标准曲线所得斜率为-3．26,相关系数为0．999。检测灵敏度达到200拷贝,方法重复性测试,检测25份临床样品CV％均小于1％。结论建立的SIVQPCR检测方法特异性、敏感性高,稳定性好,可用于定量测定猴免疫缺陷病毒（SIV）核酸拷贝量。     

TaqMan实时荧光定量RT-PCR检测甲型肝炎减毒活疫苗病毒含量的研究

目的：建立一种快速定量检测甲型肝炎减毒活疫苗病毒含量的实时荧光定量RT-PCR方法。方法对Gen-Bank中登陆的甲型肝炎减毒活疫苗株（ L-A-1）和其他甲型肝炎病毒基因组全序列比较分析,根据其高度保守的5′端非编码区设计针对甲型肝炎减毒活疫苗株特异性引物与探针,对荧光定量RT-PCR反应条件进行优化,检测该方法的特异性和灵敏性,并对甲型肝炎减毒活疫苗病毒含量进行定量检测。结果该方法对甲型肝炎减毒活疫苗株高度特异,扩增片段为207 bp,不与其他肠道病毒发生非特异性反应。在104 CCID50/管～10-1 CCID50/管之间有良好的扩增曲线,检测的灵敏度可达0．1CCID50～0．01CCID50,比普通RT-PCR高100倍。结论该方法具有快速、灵敏、特异、重复性好等优点,可应用于甲型肝炎减毒活疫苗生产过程中病毒含量滴度测定及指导疫苗成品的配制。