Legionella septentrionalis sp. nov., isolated from aquatic environments in the northern PR China.

Four strains (km711T, km714, km542 and km524), representing a novel Legionella species, were isolated from aquatic environments in northern PR China. Cells were Gram-stain-negative, rod-shaped, microaerobic, motile and growth depended on l-cysteine. They grew at 25‒42 °C (optimum, 35‒37 °C) and could tolerate up to 1.5 % (w/v) NaCl (optimum, 0.5 %). The major fatty acids (>5 %) of the type strain km711T were C17 : 0 anteiso, C15 : 0 anteiso, iso-C16 : 0 and C16 : 1 ω7c and/or iso-C15 : 0 2OH. The pairwise comparison values were <96.1 % for 16S rRNA gene sequences, 23.3‒28.7 % interspecies variation for mip gene sequences, <93.6 % average nucleotide identity and <72.8 % average amino acid identity between these four strains and related type strains within the genus Legionella. The phylogenetic tree based on the four concatenated genes (16S rRNA, mip, rpoB and rnpB) and protein-concatamer tree based on concatenation of 21 protein markers both revealed that these four strains formed a separate phylogenetic branch cluster within the genus Legionella. The results of phenotypic and genotypic features suggest that these four strains represent a novel species of the genus Legionella, for which the name Legionella septentrionalis sp. nov. is proposed (type strain km711T=KCTC 15655T=NBRC 113219T).

Syndrome Differentiation Analysis on Mars500 Data of Traditional Chinese Medicine.

Mars500 study was a psychological and physiological isolation experiment conducted by Russia, the European Space Agency, and China, in preparation for an unspecified future manned spaceflight to the planet Mars. Its intention was to yield valuable psychological and medical data on the effects of the planned long-term deep space mission. In this paper, we present data mining methods to mine medical data collected from the crew consisting of six spaceman volunteers. The synthesis of the four diagnostic methods of TCM, inspection, listening, inquiry, and palpation, is used in our syndrome differentiation. We adopt statistics method to describe the syndrome factor regular pattern of spaceman volunteers. Hybrid optimization based multilabel (HOML) is used as feature selection method and multilabel k-nearest neighbors (ML-KNN) is applied. According to the syndrome factor statistical result, we find that qi deficiency is a base syndrome pattern throughout the entire experiment process and, at the same time, there are different associated syndromes such as liver depression, spleen deficiency, dampness stagnancy, and yin deficiency, due to differences of individual situation. With feature selection, we screen out ten key factors which are essential to syndrome differentiation in TCM. The average precision of multilabel classification model reaches 80%.

Non-invasive prenatal diagnosis of trisomy 21 by reverse transcriptase multiplex ligation-dependent probe amplification.

BACKGROUND: Obtaining fetal DNA or RNA by either chorionic villus sampling (CVS) or amniocentesis is currently, the gold standard prenatal diagnosis. However, these invasive procedures carry risk of miscarriage. A reliable method for non-invasive prenatal diagnosis (NIPD) has long been sought to reduce the risk of miscarriage. METHODS: Cell-free fetal RNA was extracted from the plasma of peripheral blood from 121 women 9-20 weeks of pregnancy. Five single nucleotide polymorphism (SNP) loci in PLAC4 gene were analyzed by reverse transcriptase multiplex ligation-dependent probe amplification (RT-MLPA), followed by capillary electrophoresis. Karyotype analysis was used for confirmation of prenatal diagnosis of trisomy 21. RESULTS: Of 121 samples, 23 were diagnosed with trisomy 21, 87 with normal ploidy, nine had all five SNP loci homozygous and two had one heterozygous SNP locus. Comparing with karyotype analysis, the diagnostic sensitivity and specificity of RT-MLPA were 92% and 100%, respectively. CONCLUSIONS: RT-MLPA is a convenient and reliable method for the diagnosis of trisomy 21. We have shown that this method has good specificity, high sensitivity, and high throughput, making this technique applicable for NIPD in clinical practice.

[Genotyping for CYP2C19 with multiplex PCR point mutation screening technology].

OBJECTIVE: To establish a multiplex PCR point mutation screening technique for the genotyping of CYP2C19. METHODS: Deoxyinosine multiplex-polymerase chain reaction (PCR) primers (DMPs) were designed to detect simultaneously CYP2C19*1,*2,*3 alleles in one PCR tube. RESULTS: The above technique could detect the genotypes of CYP2C19*1, CYP2C19*2 and CYP2C19*3 successfully. And the results were completely consistent with those of DNA sequencing. CONCLUSION: A novel screening technique of multiplex PCR point mutation is successfully established. With the advantages of high specificity, convenient handling, fast completion and low cost, it provides a reasonable and reliable detection method for basic researches and personalized medicine.

Micro-Drilling of Sapphire using Electro Chemical Discharge Machining.

Electrochemical discharge machining (ECDM) refers to a non-traditional machining method for performing effective material removal on non-conductive hard and brittle materials. To increase the ECDM machining efficiency, traditionally, the method of increasing the machining voltage or increasing the electrolyte concentration is used. These methods can also cause overcut reaming of the drilled holes and a rough surface on the heat affected area. In this study, an innovative combinational machining assisted method was proposed and a self-developed coaxial-jet nozzle was used in order to combine two assisted machining methods, tool electrode rotation and coaxial-jet, simultaneously. Accordingly, the electrolyte of the machining area was maintained at the low liquid level and the electrolyte was renewed at the same time, thereby allowing the spark discharge to be concentrated at the contact surface between the front end of the tool electrode and the machined material. In addition, prior to the machining and micro-drilling, the output of the machining energy assisted mechanism was further controlled and reduced. For the study disclosed in this paper, experiments were conducted to use different voltage parameters to machine sapphire specimens of a 640 µm thickness in KOH electrolyte at a concentration of 5 M.

EPO-dependent activation of PI3K/Akt/FoxO3a signalling mediates neuroprotection in in vitro and in vivo models of Parkinson's disease.

Erythropoietin (EPO) may become a potential therapeutic candidate for the treatment of the neurodegenerative disorder -- Parkinson's disease (PD), since EPO has been found to prevent neuron apoptosis through the activation of cell survival signalling. However, the underlying mechanisms of how EPO exerts its neuroprotective effect are not fully elucidated. Here we investigated the mechanism by which EPO suppressed 6-hydroxydopamine (6-OHDA)-induced neuron death in in vitro and in vivo models of PD. EPO knockdown conferred 6-OHDA-induced cytotoxicity. This effect was reversed by EPO administration. Treatment of PC12 cells with EPO greatly diminished the toxicity induced by 6-OHDA in a dose- and time-dependent manner. EPO effectively reduced apoptosis of striatal neurons and induced a significant improvement on the neurological function score in the rat models of PD. Furthermore, EPO increased the expression of phosphorylated Akt and phosphorylated FoxO3a, and abrogated the 6-OHDA-induced dysregulation of Bcl-2, Bax and Caspase-3 in PC12 cells and in striatal neurons. Meanwhile, the EPO-dependent neuroprotection was notably reversed by pretreatment with LY294002, a specific inhibitor of phosphatidylinositol 3-kinase (PI3K). Our data suggest that PI3K/Akt/FoxO3a signalling pathway may be a possible mechanism involved in the neuroprotective effect of EPO in PD.

A library of L-tyrosine-derived biodegradable polyarylates for potential biomaterial applications, part I: synthesis, characterization and accelerated hydrolytic degradation.

A combinatorial library of biodegradable polyarylates derived from L-tyrosine was synthesized and characterized. These polyarylates are A-B-type co-polymers consisting of a cyclic dipeptide and a diacid. General structure-property correlations were established by comparing aryl diacid co-polymers and aliphatic diacid co-polymers. The synthesized polymers were characterized by FT-IR, (1)H-NMR, (13)C-NMR for their chemical structure, by DSC and TGA for their thermal characteristics and by GPC for their molecular weight distribution. The T(g) of polymers decreased and water absorption increased with increasing number of methylene groups in the polymer backbone. Using a cyclic peptide derived from L-tyrosine as co-monomer we obtained optimum bioactivity and biocompatibility. Combinatorial approaches of designing material increased effectively the number of available degradable polymers which can be used in different biomaterials applications. General structure-property correlation makes polymers' properties varied in a predictable and systematic fashion. Accelerated hydrolytic degradation studies of polyarylates were performed at 70 degrees C in acid and alkali medium. The degradation rates of polymers were in accordance with their water absorption. The degradation rates of samples in acid medium were lower than those in alkali medium.

[Association between SNAP-25 gene polymorphism and attention deficit hyperactivity disorder].

OBJECTIVE: To analyse the association between polymorphism in human synaptosomal-associated protein of 25 000 (SNAP-25) gene and attention deficit hyperactivity disorder (ADHD) in Han Chinese children. METHODS: The study samples were comprised of 100 integrated ADHD trios (included proband and biological parents) and 97 unrelated controls. Association of polymorphism with ADHD and its subtype was examined by: (1) comparing cases and controls; (2) using family-based association study in transmission disequilibrium test (TDT). RESULTS: Case-control analysis of short tandem repeat (STR) showed that there was no significant difference between the two groups in allele gene frequency and genotype frequency (P > 0.05); TDT analysis of the rs363006 SNP and the rs362549 SNP revealed no association between SNAP-25 polymorphisms and ADHD (P > 0.05). But after a stratification by ADHD subtype, the rs362549 SNP A allele showed a tendency to preferentially transmitted to ADHD-I subtype (chi(2) = 8.00, P < 0.01); and the rs362549 SNP G allele had a tendency to preferentially transmitted to ADHD-C subtype (chi(2) = 4.122, P < 0.05). CONCLUSIONS: No association was found between SNAP-25 polymorphisms and ADHD. There was a possible association between rs362549 SNP polymorphism and ADHD subtypes, but the findings require replication before drawing a definitive conclusion.