The role of autophagy in Parkinson's disease

Although Parkinson＇s disease is the most common neurodegenerative movement disorder, the mechanisms of pathogenesis remain poorly understood. Recent findings have shown that deregulation of the autophagy-lysosome pathway is involved in the pathogenesis of Parkinson＇s disease. This review summarizes the most recent findings and discusses the unique role of the autophagy-lysosome pathway in Parkinson＇s disease to highlight the possibility of Parkinson＇s disease treatment strategies that incorporate autophagy-lysosome pathway modulation.

Raman spectra of single cell from gastrointestinal cancer patients

AIM: To explore the difference between cancer cells and normal cells, we investigated the Raman spectra of singlecells from gastrointestinal cancer patients. METHODS: All samples were obtained from 30 diagnosed as gastrointestinal cancer patients. The flesh tumor specimen is located in the center of tumor tissue, while the normal ones were 5 cm away from the outside tumor section. The imprint was put under the microscope and a single cell was chosen for Raman measurement. All spectra were collected at confocal Raman micro-spectroscopy (British Renishaw) with NIR 780 nm laser.RESULTS: We measured the Raman spectra of several cells from gastrointestinal cancer patients. The result shows that there exists the strong line at 1 002/cm with less half-width assigned to the phenylalanine in several cells. The Raman lines of white cell were lower and less, while those of red cell were not only higher in intensity and more abundant, but also had a parti cular C-N breathing stretching band of pyrrole ring at 1 620-1 540/cm. The line at 1 084/cm assigned to phosphate backbone of DNA became obviously weaker in cancer cell. The Raman spectra of stomach cancer cells were similar to those of normal cells, but the Raman intensity of cancer cells was much lower than that of normal cells, and even some lines disappear. The lines of enteric cancer cells became weaker than spectra above and many lines disappeared, and the cancer cells in different position had different fluorescence intensity.CONCLUSION: The Raman spectra of several cells from cancer patients show that the structural changes of cancer cells happen and many bonds rupture so that the biological function of cells are lost. The results indicate that Raman spectra can offer the experiment basis for the cancer diagnosis and treatment.

Porphyrins in Reverse Micelles: the Side-chain Length and the Triplet-state Lifetime

Using bis(2-ethylhexyl) sodium sulfosuccinate (AOT) as surfactant, two amphiphilic porphyrin terminated with imidazole were studied in AOT/iso-octane/water reverse micelles, intending to mimic the relationship between microenvironments in organism and the amphiphilic properties of porphyrins for photodynamic therapy drugs.

Expression manner of 5-lipoxygenase in human traumatic brain injury and astrocytoma

5-lipoxygenase (5-LO) is a key enzyme of arachidonic acid metabolism. The metabolites, leuklotrienes, are important mediators in asthma, inflammatory and allergic disorders. The activation of 5-LO includes the gathering of 5-LO,adhering onto the membranes of nuclei and entrance to the nuclei. In the central nervous system, 5-LO is widely

Cloning and Characterization of a Differentially Expressed Phenylalanine Ammonialyase Gene （liPAL） After Genome Duplication from Tetraploid Isatis indigotica Fort.

Phenylpropanoid derivatives are a complex class of secondary metabolites that have many important roles in plants during normal growth and in responses to environmental stress. Phenylalanine ammonialyase （PAL） catalyzes the first step in the biosynthesis of phenylpropanoids. In the present study, we isolated a novel phenylalanine ammonialyase gene （designated as liPAL） from tetraploid Isatis indigotica Fort. by rapid amplification of cDNA ends （RACE）, which was a cultivar from the diploid plant by genome duplication. The full-length cDNA of liPAL was 2 530-bp long with an open reading frame （ORF） of 2 178 bp encoding a polypeptide of 725 amino acid residues. Analysis of liPAL genomic DNA revealed that it was structurally similar to other plant PAL genes, with a single intron at a conserved position, and a long highly conserved second exon. Semi-quantitative RT-PCR revealed that the liPAL expression in roots and leaves from a tetraploid sample was higher than that in diploid progenitor, whereas expression of liPAL in stems was almost the same as each other. Furthermore, the highest expression of liPAL in tetraploid plant was found in roots, which was found in stems in diploid plants. Further expression analysis revealed that gibberelUn （GA3）, abscisic acid （ABA）, methyl jasmonate （MeJA） and cold treatments could up-regulate the liPAL transcription in tetraploid plants. All our findings suggest that liPAL participates not only in the defense/stress responsive pathways, but also probably in the polyploidy evolution of L indigotica.

Analysis of Serum Metabolic Profile by Ultra-performance Liquid Chromatography-mass Spectrometry for Biomarkers Discovery： Application in a Pilot Study to Discriminate Patients with Tuberculosis

Background：Tuberculosis （TB） is a chronic wasting inflammatory disease characterized by multisystem involvement,which can cause metabolic derangements in afflicted patients.Metabolic signatures have been exploited in the study of several diseases.However,the serum that is successfully used in TB diagnosis on the basis of metabolic profiling is not by much.Methods：Orthogonal partial least-squares discriminant analysis was capable of distinguishing TB patients from both healthy subjects and patients with conditions other than TB.Therefore,TB-specific metabolic profiling was established.Clusters of potential biomarkers for differentiating TB active from non-TB diseases were identified using Mann-Whitney U-test.Multiple logistic regression analysis of metabolites was calculated to determine the suitable biomarker group that allows the efficient differentiation of patients with TB active from the control subjects.Results：From among 271 participants,12 metabolites were found to contribute to the distinction between the TB active group and the control groups.These metabolites were mainly involved in the metabolic pathways of the following three biomolecules：Fatty acids,amino acids,and lipids.The receiver operating characteristic curves of3D,7D,and 11D-phytanic acid,behenic acid,and threoninyl-γ-glutamate exhibited excellent efficiency with area under the curve （AUC） values of 0.904 （95% confidence interval [CI]：0.863-0.944）,0.93 （95% CI：0.893-0.966）,and 0.964 （95% CI：0.941-0.988）,respectively.The largest and smallest resulting AUCs were 0.964 and 0.720,indicating that these biomarkers may be involved in the disease mechanisms.The combination of lysophosphatidylcholine （18∶0）,behenic acid,threoninyl-γ-glutamate,and presqualene diphosphate was used to represent the most suitable biomarker group for the differentiation of patients with TB active from the control subjects,with an AUC value of 0.991.Conclusion：The metabolic analysis results identified new serum biomarkers that can distinguish TB from non-TB diseases.The metabolomics-based analysis provides specific insights into the biology of TB and may offer new avenues for TB diagnosis.

From graphite to porous graphene-like nanosheets for high rate lithium-ion batteries

Graphene nanosheets possess a promising potential as electrodes in Li-ion batteries （LIBs）; consequently, the development of low-cost and high-productivity synthetic approaches is crudal. Herein, porous grapheneqike nanosheets （PGSs） have been synthesized from expandable graphite （EG） by initially intercalating phosphoric acid, and then performing annealing to enlarge the interlayer distance of EG, thus fadlitating the successive intercalation of zinc chloride. Subsequently, the following pyrolysis of zinc chloride in the EG interlayer promoted the formation of the porous PGS structure; meanwhile, the gas produced during the formation of the porous structure could exfoliate the EG to graphene-like nanosheets. The synthetic PGS material used as LIB anode exhibited superior Li＋ storage performance, showing a remarkable discharge capacity of 830.4 mAh.g-1 at 100 mA.g-1, excellent rate capadty of 211.6 mAh＇g-1 at 20,000 mA-g-1, and excellent cycle performance （near 100% capacity retention after 10,000 cycles）. The excellent rate performance is attributed to the Li＋ ion rapid transport in porous structures and the high electrical conductivity of graphene-like nanosheets. It is expected that PGS may be widely used as anode material for high-rate LIBs via this facile and low-cost route by employing EG as the raw material.

Aluminum-activated Oxalate Secretion does not Associate with Internal Content among Some Oxalate Accumulators

Although aluminum （AI）-activated secretion of oxalate has been considered to be an important AI-exclusion mechanism, whether it is a general response in oxalate accumulators and related to oxalate content in roots are still not clear. Here, we examined the oxalate secretion and oxalate content in some oxalate accumulators, and investigated the role of oxalate secretion in AI resistance. When oxalate content in amaranth roots was decreased by about 50% with the increased ratio of NH4^＋-N to NO3^- -N in nutrient solution, the amount of AI-activated oxalate secretion still remained constant. There was no relationship between the content of the water soluble oxalate in four species of oxalate accumulators and the amount of the AI-activated oxalate secretion in roots. Furthermore, oxalate secretion is poorly associated with AI resistance among these species. Based on the above results, we concluded that although all of the oxalate accumulators tested could secrete oxalate rapidly, the density of anion channels in plasma membrane may play a more important role in AI-activated oxalate secretion.

LEAST-SQUARES SOLUTIONS OF X^TAX = B OVER POSITIVE SEMIDEFINITE MATRIXES A

This paper is mainly concerned with solving the following two problems: Problem Ⅰ. Given X ∈ Rn×m, B . Rm×m. Find A ∈ Pn such thatwhereProblem Ⅱ. Given A ∈Rn×n. Find A ∈ SE such thatwhere F is Frobenius norm, and SE denotes the solution set of Problem I.The general solution of Problem I has been given. It is proved that there exists a unique solution for Problem II. The expression of this solution for corresponding Problem II for some special case will be derived.

Metabolic Engineering of Tropane Alkaloid Biosynthesis in Plants

Abstract: Over the past decade, the evolving commercial importance of so-called plant secondary metabolites has resulted in a great interest in secondary metabolism and, particularly, in the possibilities to enhance the yield of fine metabolites by means of genetic engineering. Plant alkaloids, which constitute one of the largest groups of natural products, provide many pharmacologically active compounds. Several genes in the tropane alkaloids biosynthesis pathways have been cloned, making the metabolic engineering of these alkaloids possible. The content of the target chemical scopolamine could be significantly increased by various approaches, such as introducing genes encoding the key biosynthetic enzymes or genes encoding regulatory proteins to overcome the specific rate-limiting steps. In addition, antisense genes have been used to block competitive pathways. These investigations have opened up new, promising perspectives for increased production in plants or plant cell culture. Recent achievements have been made in the metabolic engineering of plant tropane alkaloids and some new powerful strategies are reviewed in the present paper.

THE INVERSE PROBLEM FOR PART SYMMETRIC MATRICES ON A SUBSPACE

In this paper, the following two problems are considered:Problem Ⅰ. Given S∈E Rn×p,X,B 6 Rn×m, find A ∈ SRs,n such that AX = B, where SR8,n = {A∈ Rn×n|xT(A - AT) = 0, for all x ∈ R(S)}.Problem Ⅱ. Given A* ∈ Rn×n, find A ∈ SE such that ||A-A*|| = minA∈sE||A-A*||, where SE is the solution set of Problem Ⅰ.The necessary and sufficient conditions for the solvability of and the general form of the solutions of problem Ⅰ are given. For problem Ⅱ, the expression for the solution, a numerical algorithm and a numerical example are provided.

THE INVERSE PROBLEM OF CENTROSYMMETRICMATRICES WITH A SUBMATRIX CONSTRAINT

By using Moore-Penrose generalized inverse and the general singular value decomposition of matrices, this paper establishes the necessary and sufficient conditions for the existence of and the expressions for the centrosymmetric solutions with a submatrix constraint of matrix inverse problem AX = B. In addition, in the solution set of corresponding problem, the expression of the optimal approximation solution to a given matrix is derived.

THE NEAREST BISYMMETRIC SOLUTIONS OF LINEAR MATRIX EQUATIONS

The necessary and sufficient conditions for the existence of and the expressions for the bisymmetric solutions of the matrix equations (Ⅰ)A1X1B1+A2X2B2+^…+AkXkBk=D，(Ⅱ)A1XB1+A2XB2+…+AkXBk=D and (Ⅲ) (A1XB1，A2XB2,…,AkXBk)=(D1,D2,…,Dk) are derived by using Kronecker product and Moore-Penrose generalized inverse of matrices. In addition, in corresponding solution set of the matrix equations, the explicit expression of the nearest matrix to a given matrix in the Frobenius norm is given. Numerical methods and numerical experiments of finding the neaxest solutions axe also provided.

DsMTOPVIB Promotes Meiotic DNA Double-Strand Break Formation in Rice

Dear Editor,Meiotic recombination is initiated by the generation of DNA double-strand breaks （DSBs）, which are catalyzed by the Spo11 protein （de Massy, 2013）. Two key findings point to the role of Spo11 as the initiator of DSB formation in budding yeast： （1） Spo11 is linked to the 5＇ termini of the broken DNA molecules in rad50s mutants, whose meiosis has been blocked at the stage of the cleavaqe reaction （＇Keenev et al., 1997）.

Synthesis of Iminosugar-Containing KRN7000 Analogues

Three new iminosugar-containing KRN7000 （also referred to as α-GalCer） analogues were designed and syn- thesized. In the design, the galactose moiety of KRN7000 was replaced by iminosugars and the iminosugar struc- tures were connected with ceramide in different manners with a C-glycosidic bond instead of the O-glycosidic bond. To our knowledge, this is the first report in which iminosugars are incorporated in KRN7000 structure modifica- tions. The synthetic compounds were evaluated for their ability to stimulate cytokine release. The results may benefit better understanding of structure-activity relationships and facilitate future design of more KRNT000 derivatives.