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Metabolite identification remains a bottleneck in mass spectrometry (MS)-based metabolomics. Currently, this process relies heavily on tandem mass spectrometry (MS/MS) spectra generated separately for peaks of interest identified from previous MS runs. Such a delayed and labor-intensive procedure creates a barrier to automation. Further, information embedded in MS data has not been used to its full extent for metabolite identification. Multimers, adducts, multiply charged ions, and fragments of given metabolites occupy a substantial proportion (40-80%) of the peaks of a quantitation result. However, extensive information on these derivatives, especially fragments, may facilitate metabolite identification. We propose a procedure with automation capability to group and annotate peaks associated with the same metabolite in the quantitation results of opposite modes and to integrate this information for metabolite identification. In addition to the conventional mass and isotope ratio matches, we would match annotated fragments with low-energy MS/MS spectra in public databases. For identification of metabolites without accessible MS/MS spectra, we have developed characteristic fragment and common substructure matches. The accuracy and effectiveness of the procedure were evaluated using one public and two in-house liquid chromatography-mass spectrometry (LC-MS) data sets. The procedure accurately identified 89% of 28 standard metabolites with derivative ions in the data sets. With respect to effectiveness, the procedure confidently identified the correct chemical formula of at least 42% of metabolites with derivative ions via MS/MS spectrum, characteristic fragment, and common substructure matches. The confidence level was determined according to the fulfilled identification criteria of various matches and relative retention time [ABSTRACT FROM AUTHOR]

Diabetes mellitus (DM) is characterized by dysregulated energy metabolism. Resveratrol (RSV) has been shown to ameliorate hyperglycemia and hyperlipidemia in diabetic animals. However, its overall in vivo effects on energy metabolism and the underlying mechanism require further investigation. In the present study, electrospray ionization-tandem mass spectrometry was employed to characterize the urine and plasma metabolomes of control, streptozotocin-induced DM and RSV-treated DM rats. Using principal component analysis (PCA) and heat map analysis, we discovered significant differences among control and experimental groups. RSV treatment significantly reduced the metabolic abnormalities in DM rats. Compared with the age-matched control rats, the level of carnitine was lower, and the levels of acetylcarnitine and butyrylcarnitine were higher in the urine and plasma of DM rats. RSV treatment ameliorated the deranged carnitine metabolism in DM rats. In addition, RSV treatment attenuated the diabetic ketoacidosis and muscle protein degradation, as evidenced from the attenuation of elevated urinary methyl-histidine and plasma branched-chain amino acids levels in DM rats. The beneficial effects of RSV in DM rats were correlated with activation of hepatic AMP-activated protein kinase and SIRT1 expression, increase of hepatic and muscular mitochondrial biogenesis and inhibition of muscle NF-κB activities. We concluded that RSV possesses multiple beneficial metabolic effects in insulin-deficient DM rats, particularly in improving energy metabolism and reducing protein wasting. [ABSTRACT FROM AUTHOR]

Protonolysis reactions of [(Me3Si)2N]3Ln(μ-Cl)Li(THF)3(Ln = Pr, Nd, Sm, Eu) with 3 equiv of 4,6-dimethylpyrimidine-2-thiol (dmpymtH) gave rise to the four Ln(III) pyrimidine-2-thionate complexes Li[Ln(dmpymt)4] (Ln = Pr (1), Nd (2), Sm (3), Eu (4)). Compounds 1−4were characterized by elemental analysis, IR and 1H NMR spectroscopy, and single-crystal X-ray diffraction. X-ray diffraction analysis shows that the structures of 1−4are similar and each eight-coordinate Ln(III) ion is chelated by four dmpymt ligands. Complexes 1−4display excellent catalytic performance in the cyclodimerization of isocyanates to produce substituted ureas via elimination of CO, which represents the first example of lanthanide thiolates exhibiting a high catalytic activity and a high selectivity in the cyclodimerization of isocyanates. The effects of the solvents, temperatures, catalyst loadings, and rare-earth metals on the catalytic activities of the complexes were examined. [ABSTRACT FROM AUTHOR]

Protonolysis reactions of [Zn(dmpzm)Et2] (1) with acetic or formic acid in different molar ratios gave rise to four mononuclear zinc complexes [ZnEt(dmpzm)(L)] (2: L = OAc; 3: L = HCOO) and [Zn(dmpzm)(L)2] (4: L = OAc; 5: L = HCOO), one nonanuclear zinc complex [Zn(μ4-O)2(ZnEt)6- (μ3-OAc)4(μ'3-OAc)2{Zn(dmpzm)Et}2] (6), and one tetranuclear zinc complex [Zn4(μ4-O)(dmpzm)3Et3] (7). Compounds 1-7 were characterized by elemental analysis, IR spectra, 1H NMR spectra, and the crystal structures of 1, 3, 4, 6, and 7 were determined by single-crystal X-ray crystallography. In the structures of 1, 3, and 4, the central Zn atom is tetrahedrally coordinated by two N atoms of one dmpzm and two C atoms of two Et groups (1), or one C atom of one Et group and one O atom of formate ligand (3), or two O atoms of two acetates (4). In the structure of 6, a heptanuclear [Zn(μ4-O)2(ZnEt)6(μ3-OAc)4] core is connected with two [Zn(dmpzm)Et]+ fragments via a pair of μ'3-OAc ligands. Compound 7 consists of a Zn4(μ4-O) tetrahedron in which three Zn atoms are further saturated by two N atoms from dmpzm ligands and an ethyl group while one Zn center is coordinated by three C atoms from the methylene group of the three dmpzm ligands. [ABSTRACT FROM AUTHOR]

Protonolysis reactions of [Zn(dmpzm)Et2] (1) with acetic or formic acid in different molar ratios gave rise to four mononuclear zinc complexes [ZnEt(dmpzm)(L)] (2: L = OAc; 3: L = HCOO) and [Zn(dmpzm)(L)2] (4: L = OAc; 5: L = HCOO), one nonanuclear zinc complex [Zn(μ4-O)2(ZnEt)6(μ3-OAc)4(μ′3-OAc)2{Zn(dmpzm)Et}2] (6), and one tetranuclear zinc complex [Zn4(μ4-O)(dmpzm)3Et3] (7). Compounds 1–7were characterized by elemental analysis, IR spectra, 1H NMR spectra, and the crystal structures of 1, 3, 4, 6, and 7were determined by single-crystal X-ray crystallography. In the structures of 1, 3, and 4, the central Zn atom is tetrahedrally coordinated by two N atoms of one dmpzm and two C atoms of two Et groups (1), or one C atom of one Et group and one O atom of formate ligand (3), or two O atoms of two acetates (4). In the structure of 6, a heptanuclear [Zn(μ4-O)2(ZnEt)6(μ3-OAc)4] core is connected with two [Zn(dmpzm)Et]+fragments viaa pair of μ′3-OAc ligands. Compound 7consists of a Zn4(μ4-O) tetrahedron in which three Zn atoms are further saturated by two N atoms from dmpzm ligands and an ethyl group while one Zn center is coordinated by three C atoms from the methylene group of the three dmpzm ligands. [ABSTRACT FROM AUTHOR]

Fibroblasts derived from glucose-6-phosphate dehydrogenase (G6PD)-deficient patients display retarded growth and accelerated cellular senescence that is attributable to increased accumulation of oxidative DNA damage and increased sensitivity to oxidant-induced senescence, but not to accelerated telomere attrition. Here, we show that ectopic expression of hTERT stimulates telomerase activity and prevents accelerated senescence in G6PD-deficient cells. Stable clones derived from hTERT-expressing normal and G6PD-deficient fibroblasts have normal karyotypes, and display no sign of senescence beyond 145 and 105 passages, respectively. Activation of telomerase, however, does not prevent telomere attrition in earlier-passage cells, but does stabilize telomere lengths at later passages. In addition, we provide evidence that ectopic expression of hTERT attenuates the increased sensitivity of G6PD-deficient fibroblasts to oxidant-induced senescence. These results suggest that ectopic expression of hTERT, in addition to acting in telomere length maintenance by activating telomerase, also functions in regulating senescence induction. [ABSTRACT FROM AUTHOR]

Oxidative stress has been associated with degenerative diseases such as cardiovascular and neurodegenerative diseases. Acute myocardial infarction (AMI) is the major cause of death among cardiovascular diseases. Inflammation, a major risk factor of AMI, is associated with leukocytic activation, secretion of myeloperoxidase (MPO) and subsequent oxidant generation. It has been hypothesized that oxidative stress is a risk factor for AMI. To test this hypothesis, we studied profiles of oxidative damage and antioxidants in patients with AMI. The levels of MPO, 8-OHdG, and 3-Cl-Tyr were higher in blood specimens from AMI patients than in those of controls. Antioxidant levels, such as vitamin E and glutathione peroxidase, were significantly lower in these patients. The GSH/GSSG ratio, indicative of redox status, was also lower in AMI patients. Such findings suggest that these AMI patients experience increased oxidative stress. Moreover, markers in combination are better for evaluating antioxidant status and monitoring cardiac events than the same markers used separately. [ABSTRACT FROM AUTHOR]

Glucose-6-phosphate dehydrogenase (G6PD), the first and rate-limiting enzyme of the pentose phosphate pathway, is indispensable to maintenance of the cytosolic pool of NADPH and thus the cellular redox balance. The role of G6PD as an antioxidant enzyme has been recognized in erythrocytes for a long time, as its deficiency is associated with neonatal jaundice, drug- or infection-mediated hemolytic crisis, favism and, less commonly, chronic non-spherocytic hemolytic anemia. To a large extent, advances in the field were made on the pathophysiology of G6PD-deficient erythrocytes, and the molecular characterization of different G6PD variants. Not until recently did numerous studies cast light on the importance of G6PD in other aspects of the physiology of both cells and organisms. Deficiency in G6PD activity, and hence a disturbance in redox homeostasis, can lead to dysregulation of cell growth and signaling, anomalous embryonic development, altered susceptibility to viral infection as well as increased susceptibility to degenerative diseases. The present review covers recent developments in this field. Additionally, molecular characterization of G6PD variants, especially those frequently found in Taiwan and Southern China, is also addressed. [ABSTRACT FROM AUTHOR]

OBJECTIVE--Metabolic syndrome is a multiplex disorder and puts patients on the road to type 2 diabetes and atherosclerotic cardiovascular diseases. However, a surrogate biomarker in plasma or urine in fully reflecting features of metabolic syndrome has not been explored. RESEARCH DESIGN AND METHODS--Urine metabolomics has potential utility in metabolic profiling because urine metabolites analysis reflects global outflux of metabolic change. Accordingly, we collected data on subjects (n = 99) with overweight, dyslipidemia, hypertension or impaired glucose tolerance and took a metabolomics approach to analyze the metabolites of urine revealed in metabolic syndrome by high-performance liquid chromatography-time-of-flight mass spectrometry and elicit potential biomarkers to picture metabolic syndrome. RESULTS--Our results revealed that the urine nicotinuric acid value of subjects with diabetes (HbA1c $6.5% or those receiving diabetes medications) (n = 25) was higher than subjects without diabetes (n = 37) (221 ± 31 vs. 152 ± 13 X 10³ mAU, P = 0.0268). Moreover, urinary nicotinuric acid level was positively correlated with body mass index, blood pressure, total cholesterol, low-density lipoprotein cholesterol, triacylglycerol and high sensitivity C-reactive protein, but negatively correlated with high-density lipoprotein cholesterol. CONCLUSIONS--This is the first study, to our knowledge, to propose that nicotinuric acid represents an important pathogenic mechanism in process from metabolic syndrome to diabetes and atherosclerotic cardiovascular disease. [ABSTRACT FROM AUTHOR]

The reaction of [(TMS)2N]3La(μ-Cl)Li(THF)3 (1) and HSPh produced a bimetallic complex [{(TMS)2N}2La(THF)]2(μ-SPh)(μ-Cl)] (2). Compound [{(TMS)2N}2La5O(SPh)10LiCl2(THF)6] (3) was prepared by control of the hydrolysis of 2 and LiCl or 1 and HSPh with the proper amount of water. 1 was treated first with 1⁄6 equiv of H2O and then with equimolar HSPh; a polymeric complex [{(TMS)2N}2(μ-SPh)La(μ-SPh)Li(THF)2]∞ (4) was isolated. 3 contains a central [(μ-SPh)4(μ3-SPh)2{La(THF)}4(μ3-O)]4+ tetrahedral fragment in which two La atoms are linked by a pair of μ-SPh- and μ3-Cl- ligands to a [{(TMS)2N}2La]+ fragment, while the other two are bridged by two μ-SPh- ligands to a [Li(THF)2]+ fragment, forming a bee-shaped structure. [ABSTRACT FROM AUTHOR]

The Zn atom in dichloro­[(3,5-dimethyl-1 H-pyrazol-1-yl)­methane]zinc(II), [ZnCl2(C11H16N4)], (I), is tetra­hedrally coordinated by two N atoms from one bis­(3,5-dimethyl­pyrazol­yl)methane ligand and two terminal Cl atoms. The mol­ecule has no crystallographic symmetry. One H atom of the CH2 group of the bis­(3,5-dimethyl­pyrazol­yl)methane ligand inter­acts with a Cl atom of an adjacent mol­ecule to yield inter­molecular C—H⋯Cl contacts, thereby forming a one-dimensional zigzag chain extending along the b axis. On the other hand, in di-μ-chloro-bis­{chloro­[(3,5-dimethyl-1 H-pyrazol-1-yl)methane]cadmium(II)}, [Cd2Cl4(C11H16N4)2], (II), each of the two crystallographically equivalent Cd atoms is penta­coordinated by two N atoms from one bis­(3,5-dimethyl­pyrazol­yl)methane ligand, and by one terminal and two bridging Cl− anions. The mol­ecule has a crystallographic centre of symmetry located at the mid-point of the Cd⋯Cd line. One H atom of the CH2 group of the bis­(3,5-dimethyl­pyrazolyl)­methane ligand inter­acts with a Cl atom of an adjacent mol­ecule to produce pairwise inter­molecular C—H⋯Cl contacts, thereby affording chains of mol­ecules running along the c axis. [ABSTRACT FROM AUTHOR]

Phosphatidylinositol (PI) 4,5-bisphosphate (PIP2) is involved in many biological functions. However, the mechanisms of PIP2 in collective cell migration remain elusive. This study highlights the regulatory role of cytidine triphosphate synthase (CTPsyn) in collective border cell migration through regulating the asymmetrical distribution of PIP2.We demonstrated that border cell clusters containing mutant CTPsyn cells suppressed migration. CTPsyn was co-enriched with Actin at the leading edge of the Drosophila border cell cluster where PIP2 was enriched, and this enrichment depended on the CTPsyn activity. Genetic interactions of border cell migration were found between CTPsyn mutant and genes in PI biosynthesis. The CTPsyn reduction resulted in loss of the asymmetric activity of endocytosis recycling. Also, genetic interactions were revealed between components of the exocyst complex and CTPsyn mutant, indicating that CTPsyn activity regulates the PIP2-related asymmetrical exocytosis activity. Furthermore, CTPsyn activity is essential for RTK-polarized distribution in the border cell cluster. We propose a model in which CTPsyn activity is required for the asymmetrical generation of PIP2 to enrich RTK signaling through endocytic recycling in collective cell migration. [ABSTRACT FROM AUTHOR]

Assembly of a family of monomeric, dimeric, and polymeric W/Cu/S clusters from a precursor cluster [Et[sub4]N][Tp*W(μ[sub3]-S)[sub3](CuBr)[sub3]] (Tp* = hydridotris(3,5-dimethylpyrazol-1-yl)borate) (1) and various N-donor ligands was reported. The treatment of 1 with pyridine (py) or aniline (ani) in the presence of NH[sub4]PF[sub6] afforded a cationic cluster [Tp*W(μ[sub3]-S)[sub3]Cu[sub3](py)[sub3](μ[sub3]-Br)](PF[sub6]) (2) and a neutral cluster [(Tp*W(μ[sub3]-S)[sub3](CuBr)[sub3])(μ[sub6]-Br)(Tp*W(μ[sub3]-S)[sub3]Cu[sub3](ani)[sub3])] ∙ 4ani ∙ 0.5Et[sub2]O (3 ∙ 4ani 0.5Et[sub2]O). On the other hand, the treatment of 1 with excess 4,4'-bipyridine (4,4'-bipy) or 1 ,2-bis(4-pyridyl)ethylene (bpee) followed by the addition of NH[sub4]PF[sub6] led to the formation of a polymeric cluster ([Tp*W(μ[sub3]-S)[sub3]Cu[sub3](4,4'-bipy)[sub3](μ[sub3]-Br)](PF[sub6]) ∙ H[sub2]O)[subn] (4) and a neutral cluster [(Tp*W(μ[sub3]-S)[sub3]Cu[sub3]Br[sub2])[sub2](bpee)] ∙ 0.5CH[sub2]Cl[sub2] (5 ∙ 0.5CH[sub2]Cl[sub2]). Meanwhile, analogous reactions of 1 with excess 1,2-bis(4- pyridyl)ethane (bpe) or 1 ,3-bis(4-pyridyl)propane (bpp) in DMF under the presence of NH[sub4]PF[sub6] resulted in the formation of two polymeric clusters ([(Tp*W(μ[sub3]-S)[sub3]Cu[sub3](μ[sub3]-Br))[sub2](bpe)[sub3]](PF[sub6])[sub2] ∙ MeCN)[subn] (6) and ([Tp*W(μ[sub3]-S)[sub3]Cu[sub3]Br(μ[sub3]-Br)(bpp)] ∙ DMF)[subn] (7). Compounds 1-7 were characterized by elemental analysis, IR spectra, UV-vis spectra, [sup1]H NMR, electrospray ionization mass spectra, and X-ray crystallography. The anion of 1 has an incomplete cubanelike [Tp*W(μ[sub3]-S)[sub3](CuBr)[sub3]] structure, while the cation of 2 has a cubanelike (Tp*W(μ[sub3]-S)[sub3]Cu[sub3](μ[sub3]-Br)] structure. Compound 3 may be viewed as having a corner-shared double cubanelike structure that consists of one [Tp*W(μ[sub3]-S)[sub3]Cu[sub3](ani)[sub3]][sup2+] dication and one [Tp*W(μ[sub3]-S)[sub3](CuBr)[sub3]][sup—] anion linked by a p6-Br bridge. For 4, each [Tp*W(μ[sub3]-S)[sub3]Cu[sub3](μ[sub3]-Br)] unit works as a pyramidal three-connecting node to connect its equivalent ones via three 4,4'-bipy bridges to yield a 2D (6,3) cationic network. Compound 5 has a dimeric structure in which two incomplete cubanelike [Tp*W(μ[sub3]-S)[sub3]Cu[sub3]Br[sub2]] cores are bridged with one bpee ligand. For 6, each dimeric [(Tp*W(μ[sub3]-S)[sub3]Cu[sub3](μ[sub3]-Br))[sub2](bpe)[sub2]] unit is interconnected via a pair of bpe bridges to form a 1D zigzag cationic chain. Compound 7 has a 1D spiral chain in which each [Tp*W(μ[sub3]-S)[sub3]Cu[sub3]Br(μ[sub3]-Br)] core is interlinked by a couple of bpp bridges. The formation of 2-7 from the precursor cluster 1 through various N-donor ligands offers a new way to the design and assembly of the W/Cu/S clusters with interesting molecular and supramolecular arrays. [ABSTRACT FROM AUTHOR]

The host cellular environment is a key determinant of pathogen infectivity. Viral gene expression and viral particle production of glucose-6-phosphate dehydrogenase (G6PD)-deficient and G6PD-knockdown cells were much higher than their counterparts when human coronavirus (HCoV) 229E was applied at 0.1 multiplicity of infection. These phenomena were correlated with increased oxidant production. Accordingly, ectopic expression of G6PD in G6PD-deficient cells or addition of antioxidant (such as α-lipoic acid) to G6PD-knockdown cells attenuated the increased susceptibility to HCoV229E infection. All experimental data indicated that oxidative stress in host cells is an important factor in HCoV229E infectivity. [ABSTRACT FROM AUTHOR]

The chemistry of lanthanide chalcogenolate complexes has expanded dramatically in the recent years. This review summarized the syntheses and crystal structures of the lanthanide chalcogenolate complexes and their applications in organic chemistry. Four methods for the synthesis of lanthanide chalcogenolate complexes were outlined: protonolysis, metathesis, oxidation–reduction, and insertion reaction. The lanthanide chalcogenolate complexes were classified according to the ancillary ligands coordinated to lanthanide atoms and the number of lanthanide atoms, and some specific structures were briefly described. The reactivity and catalytical property of some lanthanide chalcogenolate complexes in organic and polymer synthesis along with their luminescent properties are highlighted. [Copyright &y& Elsevier]

The effects of fractionated oxidized low density lipoproteins (oxidized LDL) on the growth of vascular smooth muscle cells (VSMC) and their relationship to the formation of lysophosphatidylcholine (lyso-PC) as well as the activation of protein kinase C (PKC) were studied. VSMC were isolated from porcine aorta by explant culture. LDL was isolated from porcine blood by sequential ultracentrifugation and oxidized LDL was obtained by incubating LDL with 5 μM CuSO[sub 4] at 37°C for various lengths of time. Our results showed that LDL oxidized for 12 h and eluted from fast protein liquid chromatography at 43 min inhibited the growth of VSMC, and that LDL oxidized for longer than 48 h and eluted at 48 min stimulated the growth of VSMC. The formation of lyso-PC in the oxidized LDL correlated well with its stimulatory effect, suggesting that lyso-PC is responsible for the mitogenic effect of oxidized LDL. This stimulatory effect of oxidized LDL was inhibited by staurosporine, a PKC inhibitor. Treatment with oxidized LDL increased the activity of membrane PKC, but it decreased that of cytosolic PKC, suggesting the translocation of PKC from cytosol to the membrane in the presence of oxidized LDL. These results suggested that the oxidized LDL-stimulated VSMC growth was mediated by the formation of lyso-PC and the activation of PKC. [ABSTRACT FROM AUTHOR]

EV71 infection is generally associated with hand-foot-mouth disease (HFMD), and may cause severe neurological disorders and even death. An effective murine oral infection model for studying the pathogenesis of various clinical EV71 isolates is lacking. We developed a transgenic mouse that expresses EV71 receptor, that is human scavenger receptor class B member 2 (hSCARB2), in a pattern highly similar to that of murine endogenous mSCARB2 protein. A FLAG-tagged SCARB2 cDNA fragment composed of exon 3-12 was inserted in murine Scarb2 gene-containing bacterial artificial chromosome (BAC) clone, and the resulting transgene was used for establishment of chimeric receptor-expressing transgenic (Tg) mice. The Tg mice intragastrically (i. g.) infected with the clinical isolates of EV71 showed neurological symptoms, such as ataxia and paralysis, and fatality. There was an age-dependent decrease in the susceptibility to viral infection. Pathological characteristics of the infected Tg mice resembled those of encephalomyelitis in human patients. Viral infection was accompanied by microglial activation. Clodronate treatment of the brain slices from Tg mice enhanced viral replication, while lipopolysaccharide treatment significantly inhibited it, suggesting an antiviral role for microglia during EV71 infection. Taken together, this Tg mouse provides a model that closely mimics the natural infection for studying EV71 pathogenesis and for evaluating the efficacy of vaccine or other antiviral drugs. IMPORTANCE Availability of a murine model of EV71 infection is beneficial to the understanding of pathogenic mechanism and to development and assessment of vaccine and antiviral drugs. However, the lack of a murine oral infection model thwarted the study of pathogenesis induced by the clinically relevant EV71 strain that is transmitted via the oral-oral or oral-fecal routes. Our Tg mice could be intragastrically infected with the clinically relevant EV71 strains in an efficient way, and developed neurological symptoms and pathologic changes strikingly resembling those of human infection. Moreover, these mice showed an age-dependent change in susceptibility that is similar to the human case. In prospect, this Tg mouse, when combined with the uses of other genetically modified mice, potentially contributes to studying the relationship between developmental changes in immunity and the susceptibility to virus. [ABSTRACT FROM AUTHOR]

Background: γ-Carboxymuconolactone decarboxylase (CMD) participates in the β-ketoadipate pathway, which catalyzes aromatic compounds to produce acetyl- or succinyl-CoA, in prokaryotes and yeast. Our previous study demonstrated that expression of a CMD homologue that contains two signatures (dualCMD) is negatively regulated by iron in Trichomonas vaginalis. However, we were not able to identify the components of the β-ketoadipate pathway in the parasite’s genome. These observations prompted us to investigate the biological functions of this novel CMD homologue in T. vaginalis. Methods: The specific anti-TvCMD1 antibody was generated, and the expression of TvCMD1 in T. vaginalis cultured under iron-rich and iron-deficient were evaluated. Phylogenetic, metabolomic and substrate induction (protocatechuate and benzoate) analysis were conducted to clarify the function of dualCMD in trichomonad cells. Subcellular localization of TvCMD1 was observed by confocal microscopy. The cell cycle-related role of TvCMD1 was assessed by treating cells with G2/M inhibitor nocodazole. Results: We confirmed that T. vaginalis is not able to catabolize the aromatic compounds benzoate and protocatechuate, which are known substrates of the β-ketoadipate pathway. Using immunofluorescence microscopy, we found that TvCMD1 is spatially associated with the basal body, a part of the cytoskeletal organizing center in T. vaginalis. TvCMD1 accumulated upon treatment with the G2/M inhibitor nocodazole. Additionally, TvCMD1 was expressed and transported to/from the basal body during cytokinesis, suggesting that TvCMD1 plays a role in cell division. Conclusion: We demonstrated that TvCMD1 is unlikely to participate in the β-ketoadipate pathway and demonstrated that it is a novel basal body-localizing (associated) protein. This model sheds light on the importance of genes that are acquired laterally in the coevolution of ancient protists, which surprisingly functions in cell cycle regulation of T. vaginalis. [ABSTRACT FROM AUTHOR]

Statins have been reported to induce tendinopathy and even tendon rupture. The present study was designed to investigate the potential molecular mechanism underlying the adverse effect of simvastatin on tendon cells. An in vitro tendon healing model was performed using tendon cells isolated from rat Achilles tendons. The viability of tendon cells and cell cycle progression were examined by the MTT assay and flow cytometric analysis, respectively. Immunofluorescent staining for Ki-67 was used to assess the proliferation activity of tendon cells. Western blot analysis and coimmunoprecipitation was used to determine the protein expression of cell cycle-related proteins. To investigate the potential mechanism underlying the effect of statins on tendon cells, mevalonate, farnesyl pyrophosphate (FPP), or geranylgeranyl pyrophosphate (GGPP) was added to simvastatin-treated tendon cells. Simvastatin inhibited the in vitro tendon healing model and tendon cell proliferation in a dose-dependent manner. Immunofluorescent staining demonstrated reduced ki-67 expression in simvastatin-treated tendon cells. Furthermore, simvastatin induced cell cycle arrest at the G1 phase. The expression levels of cdk1, cdk2, cyclin A, and cyclin E were downregulated by simvastatin in a dose-dependent manner. The inhibitory effect of simvastatin was proved to mediate the reduction of mevalonate, and the addition of exogenous GGPP completely prevented the inhibitory effect of simvastatin on tendon cells. The present study demonstrated, for the first time, the molecular mechanism underlying simvastatin-induced tendinopathy or tendon rupture. GGPP was shown to prevent the adverse effect of simvastatin in tendon cells without interfering with its cholesterol-reducing efficacy. [ABSTRACT FROM AUTHOR]

Glucose-6-phosphate dehydrogenase (G6PD)-deficient cells are highly susceptible to viral infection. This study examined the mechanism underlying this phenomenon by measuring the expression of antiviral genes--tumor necrosis factor alpha (TNF-α) and GTPase myxovirus resistance 1 (MX1)--in G6PD-knockdown cells upon human coronavirus 229E (HCoV-229E) and enterovirus 71 (EV71) infection. Molecular analysis revealed that the promoter activities of TNF-α and MX1 were downregulated in G6PD-knockdown cells, and that the IKB degradation and DNA binding activity of NF-κB were decreased. The HSCARG protein, a nicotinamide adenine dinucleotide phosphate (NADPH) sensor and negative regulator of NF-κB, was upregulated in G6PD-knockdown cells with decreased NADPH/NADP+ ratio. Treatment of G6PD-knockdown cells with siRNA against HSCARG enhanced the DNA binding activity of NF-κB and the expression of TNF-α and MX1, but suppressed the expression of viral genes; however, the overexpression of HSCARG inhibited the antiviral response. Exogenous G6PD or IDH1 expression inhibited the expression of HSCARG, resulting in increased expression of TNF-α and MX1 and reduced viral gene expression upon virus infection. Our findings suggest that the increased susceptibility of the G6PD-knockdown cells to viral infection was due to impaired NF-κB signaling and antiviral response mediated by HSCARG. [ABSTRACT FROM AUTHOR]

CTP synthase (CTPsyn) plays an essential role in DNA, RNA, and lipid synthesis. Recent studies in bacteria, yeast, and Drosophila all reveal a polymeric CTPsyn structure, which dynamically regulates its enzymatic activity. However, the molecular mechanism underlying the formation of CTPsyn polymers is not completely understood. In this study, we found that reversible ubiquitination regulates the dynamic assembly of the filamentous structures of Drosophila CTPsyn. We further determined that the proto-oncogene Cbl, an E3 ubiquitin ligase, controls CTPsyn filament formation in endocycles. While the E3 ligase activity of Cbl is required for CTPsyn filament formation, Cbl does not affect the protein levels of CTPsyn. It remains unclear whether the regulation of CTPsyn filaments by Cbl is through direct ubiquitination of CTPsyn. In the absence of Cbl or with knockdown of CTPsyn, the progression of the endocycle-associated S phase was impaired. Furthermore, overexpression of wild-type, but not enzymatically inactive CTPsyn, rescued the endocycle defect in Cbl mutant cells. Together, these results suggest that Cbl influences the nucleotide pool balance and controls CTPsyn filament formation in endocycles. This study links Cbl-mediated ubiquitination to the polymerization of a metabolic enzyme and reveals a role for Cbl in endocycles during Drosophila development. [ABSTRACT FROM AUTHOR]

The surface of a clay teapot tends to be coated with a waterproof film after constant use for tea preparation. The waterproof films of two kinds of teapots (zisha and zhuni) used for preparing oolong tea and old oolong tea were extracted and subjected to gas chromatography-mass spectrometry analysis. The results showed that comparable constituents were detected in these films; they were primarily fatty acids and linear hydrocarbons that were particularly rich in palmitic acid and stearic acid. To explore the source of these two abundant fatty acids, the fatty acid compositions of fresh tea leaves, granules, infusion, and vapor of infusion were analyzed by gas chromatography. Fresh tea leaves were rich in palmitic acid (C-16:0), unsaturated linolenic acid (C-18:3), linoleic acid (C-18:2), and oleic acid (C-18:1), which were presumably from the phospholipid membrane. During the process of manufacturing oolong tea, the three unsaturated fatty acids may be substantially degraded or oxidized to stearic acid (C-18:0), which was enriched with palmitic acid in the tea granules and in the infusion. The vapor of the tea infusion is primarily composed of palmitic acid and stearic acid. Thus, the coated films of teapots mostly originated from the lipophilic compounds of the tea infusions. [ABSTRACT FROM AUTHOR]

Background Methionine, an essential amino acid, is required for protein synthesis and normal cell metabolism. The transmethylation pathway and methionine salvage pathway (MTA cycle) are two major pathways regulating methionine metabolism. Recently, methionine has been reported to play a key role in Drosophila fecundity Results Here, we revealed that the MTA cycle plays a crucial role in Drosophila fecundity using the mutant of aci-reductone dioxygenase 1 (DADI1), an enzyme in the MTA cycle. In dietary restriction condition, the egg production of adi1 mutant flies was reduced compared to that of control flies. This fecundity defect in mutant flies was rescued by reintroduction of Dadi1 gene. Moreover, a functional homolog of human ADI1 also recovered the reproduction defect, in which the enzymatic activity of human ADI1 is required for normal fecundity. Importantly, methionine supply rescued the fecundity defect in Dadi1 mutant flies. The detailed analysis of Dadi1 mutant ovaries revealed a dramatic change in the levels of methionine metabolism. In addition, we found that three compounds namely, methionine, SAM and Methionine sulfoxide, respectively, may be required for normal fecundity Conclusions In summary, these results suggest that ADI1, an MTA cycle enzyme, affects fly fecundity through the regulation of methionine metabolism. [ABSTRACT FROM AUTHOR]

Manganese-based layered coordination polymer ([Mn-(tfbdc)(4,4'-bpy)(H20)2], Mn--LCP) with microporous structure was synthesized by reaction of 2,3,5,6-tetrafluoroterephthalatic acid(H2tfbdc) and 4,4'-bipyridine(4,4'-bpy) with manganese(ll) acetate tetrahydrate in water solution. Mn--LCP was characterized by elemental analysis, IR spectra, thermogravimetric analysis, X-ray single-crystal structure analysis, and powder X-ray diffraction. Magnetic susceptibility data from 300 to 1.8K show that there is a weak antiferromagnetic exchange between Mn(n) ions in Mn--LCP. As anode material, the Mn--LCP electrode exhibits an irreversible high capacity in the first discharge process and a reversible lithium storage capacity of up to about 390 mA h/g from the fourth cycle. It might provide a new method for finding new electrode materials in lithium-ion batteries [ABSTRACT FROM AUTHOR]

Huntington disease (HD) is a degenerative disorder caused by expanded CAG repeats in exon 1 of the huntingtin gene (HIT). Patients with late-stage HD are known to have abnormal auditory processing, but the peripheral auditory functions of HD patients have yet to be thoroughly assessed. In this study, 19 HD patients (aged 40-59 years) were assessed for hearing impairment using pure-tone audiometry and assessment of auditory brainstem responses (ABRs). PTA thresholds were markedly elevated in HD patients. Consistent with this, elevated ABR thresholds were also detected in two mouse models of HD. Hearing loss thus appears to be an authentic symptom of HD. Immunohistochemical analyses demonstrated the presence of mutant huntingtin that formed intranuclear inclusions in the organ of Corti of HD mice, which might interfere with normal auditory function. Quantitative RT-PCR and Western blot analyses further revealed reduced expression of brain creatine kinase (CKB), a major enzyme responsible for ATP regeneration via the phosphocreatine-creatine kinase (PCr-CK) system, in the cochlea of HD mice. Treatment with creatine supplements ameliorated the hearing impairment of HD mice, suggesting that the impaired PCr-CK system in the cochlea of HD mice may contribute to their hearing impairment. These data also suggest that creatine may be useful for treating the hearing abnormalities of patients with HD. [ABSTRACT FROM AUTHOR]

The free-volume depth profile of asymmetric polymeric membrane systems prepared by interfacial polymerization is studied using positron annihilation spectroscopy coupled with a variable monoenergy slow positron beam. Significant variations of S, W, andRparameters from the Doppler broadened energy spectra vs positron incident energy up to 30 keV and orthopositronium lifetime and intensity are observed at different doping times of triethylenetetraamine (TETA) reacting with trimesoyl chloride (TMC) in an interfacial polymerization on modified porous polyacrylonitrile (PAN) asymmetric membrane. The positron annihilation data are analyzed in terms of free-volume parameters as a function of depth from the surface to nano- and micrometer regions of asymmetric membranes. A multilayer structure is obtained in polymerized polyamide (PA) on modified PAN membranes (m-PAN):  a nanometer scale skin polyamide layer, a nanometer to micrometer scale transition layer from dense to porous m-PAN, and the porous m-PAN support. The results of free-volume parameters and obtained layer thicknesses are compared with the flux (permeability) and water concentration in permeate (selectivity) through the pervaporation separation of 70 wt % 2-propanol aqueous solution. It is found that the water concentration in permeate is mainly controlled by the free-volume properties of skin polyamide and weakly related to the transition layer from the skin to porous m-PAN. The obtained layer structures of asymmetric polymeric membranes are supported by the data obtained by AFM, SEM, and ATR−FTIR. [ABSTRACT FROM AUTHOR]

Reactions of anhydrous lanthanide(III) trichloride (Ln = Nd, Sm, Eu, Ho, Yb) with one or two equiv. of LiN(SiMe3)2 in THF produced a family of lanthanide(III) bis(trimethylsilyl)amide chloride complexes: [ ((Me3Si)2N)2Nd(mu'-Cl)Li(THF)3 (mu-Cl)]2 (1), [ ((Me3Si)2N)2Ln(mu'-Cl)Li(THF)2 (mu3-Cl)]2 (Ln = Eu (2); Ln = Ho (3)), and [ (Me3Si)2NLn(mu'-Cl)2Li(THF)2 (mu-Cl)]2 (Ln = Nd (4); Ln = Sm (5); Ln = Eu (6); Ln = Ho (7); Ln = Yb (8)). On the other hand, reactions of the monosubstituted silylamido complexes [ (Me3Si)2NLn(mu'-Cl)2Li(THF)2 (mu-Cl)]2 (Ln = Nd (4); Sm (5); Eu (6); Ho (7)) with 2 equiv. of LiN(SiMe3)2 in THF afforded the corresponding disubstituted complexes [ ((Me3Si)2N)2Ln(mu'-Cl)Li(THF)3 (mu-Cl)]2 (Ln = Nd (1); Sm (9)), [ ((Me3Si)2N)2Ln(mu'-Cl)Li(THF)2 (mu3-Cl)]2 (Ln = Sm (9), Eu (2); Ho (3)). These complexes were characterized by melting point determination, elemental analysis and IR spectra. Single-crystal X-ray diffraction studies revealed that these compounds are chloride-bridged dimers, in which Ln metals in 1-3 display a distorted trigonal bipyramidal coordination geometry while those in 5, 6 and 8 a distorted octahedral coordination geometry. Complexes 1-9 exhibited catalytic activity for the ring-opening polymerization of epsilon-caprolactone. [ABSTRACT FROM AUTHOR]