Novel chemotactic For-Met-Leu-Phe-OMe (fMLF-OMe) analogues based on Met residue replacement by 4-amino-proline scaffold: Synthesis and bioactivity

cis-(2S,4S) 4-Amino-proline (cAmp) and trans-(2S,4R) 4-amino-proline (tAmp) residues, bearing N-For or N-Boc substituents at the two amino groups, have been incorporated into the potent chemotactic agent fMLF-OMe in place of the N-terminal native (S)-methionine to give the analogues 17a–19a and 17b–19b. The new ligands have been examined for their activity (chemotaxis, superoxide anion production and lysozyme release) on human neutrophils as agonists and antagonists. Compounds 19a and 19b, bearing two N-For groups at the proline scaffold, are active and selective chemoattractants. The ligand 18b, containing N-For at the 4-amino group of the N-Boc-tAmp residue, exhibits significant chemotactic antagonism. The influence of the different substitution at the N-terminal position of the new analogues is discussed.     

Triterpenes from Douglas fir sapwood

The saponified ether-soluble extractives of Douglas fir sapwood contained (24R)- 4α,14α,24-trimethyl-9β,19-cyclo-5α-cholestan-3β-ol(24R-cyclocucalanol),a new natural product; 4α,14α-dimethyl-9β,19-cyclo-24-methylene-5α-cholestan-3β- ol (cycloeucalenol); and (24R)-4α,24-dimethyl-5α-cholest-7-en-3β-ol (24R- methyllophenol); this is the first time they have been reported from Douglas fir.     

neo-Clerodane diterpenes from Ajuga ciliata and their inhibitory activities on LPS-induced NO production

Two new neo-clerodane diterpenes, (12S)-6α-acetoxy-4α,18-epoxy-12-hydroxy-19-tigloyloxy-neo-clerod-13-en-15,16-olide (1) and 6α,18-diacetoxy-4α-hydroxy-19-tigloyloxy-neo-clerod-13-en-15,16-olide (2), along with three known analogs (3–5) have been isolated from the whole plants of Ajuga ciliata Bunge. Their structures were elucidated on the basis of spectroscopic data analyses (IR, ESI-MS, HR-ESI-MS, HMQC, HMBC, COSY, and NOESY). The inhibitory activities on LPS-induced NO production of these diterpenes were evaluated and compounds 1 and 5 showed inhibitory effects.     

Cucurbitane-type triterpenoids from the aerial parts of Momordica charantia L.

Six new cucurbitane-type triterpenoids (1–6), together with two known analogues (7 and 8) were isolated from the aerial parts of Momordica charantia L. The structures of new compounds were identified as cucurbita-6,24-dien-3β,23-diol-19,5β-olide (1), (19R)-5β,19-epoxy-19-methoxycucurbita-6,24-dien-3β,23-diol (2), (19S)-5β,19-epoxy-19-methoxycucurbita-6,24-dien-3β,23-diol (3), (19R)-5β,19-epoxy-19-isopropoxycucurbita-6,24-dien-3β,23-diol (4), 3β,23-dihydroxy-5-methoxycucurbita-6,24-dien-19-al (5) and (19R)-7β,19-epoxy-19-methoxycucurbita-5,24-dien-3β,23-diol (6), by extensive MS, 1D and 2D NMR spectroscopic technologies. This is the first report of the isolation of tetracyclic triterpenoids possessing a 7β,19-epoxy system, viz., 6, from M. charantia L.     

Genome-wide association meta-analysis identifies pleiotropic risk loci for aerodigestive squamous cell cancers

Squamous cell carcinomas (SqCC) of the aerodigestive tract have similar etiological risk factors. Although genetic risk variants for individual cancers have been identified, an agnostic, genome-wide search for shared genetic susceptibility has not been performed. To identify novel and pleotropic SqCC risk variants, we performed a meta-analysis of GWAS data on lung SqCC (LuSqCC), oro/pharyngeal SqCC (OSqCC), laryngeal SqCC (LaSqCC) and esophageal SqCC (ESqCC) cancers, totaling 13,887 cases and 61,961 controls of European ancestry. We identified one novel genome-wide significant (P_meta<5x10^-8) aerodigestive SqCC susceptibility loci in the 2q33.1 region (rs56321285, TMEM273). Additionally, three previously unknown loci reached suggestive significance (P_meta<5x10^-7): 1q32.1 (rs12133735, near MDM4), 5q31.2 (rs13181561, TMEM173) and 19p13.11 (rs61494113, ABHD8). Multiple previously identified loci for aerodigestive SqCC also showed evidence of pleiotropy in at least another SqCC site, these include: 4q23 (ADH1B), 6p21.33 (STK19), 6p21.32 (HLA-DQB1), 9p21.33 (CDKN2B-AS1) and 13q13.1(BRCA2). Gene-based association and gene set enrichment identified a set of 48 SqCC-related genes rel to DNA damage and epigenetic regulation pathways. Our study highlights the importance of cross-cancer analyses to identify pleiotropic risk loci of histology-related cancers arising at distinct anatomical sites.     

The Promise of Pharmacogenomics in Reducing Toxicity During Acute Lymphoblastic Leukemia Maintenance Treatment

Pediatric acute lymphoblastic leukemia(ALL) affects a substantial number of children every year and requires a long and rigorous course of chemotherapy treatments in three stages, with the longest phase, the maintenance phase, lasting 2–3 years. While the primary drugs used in the maintenance phase, 6-mercaptopurine(6-MP) and methotrexate(MTX), are necessary for decreasing risk of relapse, they also have potentially serious toxicities, including myelosuppression, which may be life-threatening, and gastrointestinal toxicity. For both drugs, pharmacogenomic factors have been identified that could explain a large amount of the variance in toxicity between patients, and may serve as effective predictors of toxicity during the maintenance phase of ALL treatment.6-MP toxicity is associated with polymorphisms in the genes encoding thiopurine methyltransferase(TPMT), nudix hydrolase 15(NUDT15), and potentially inosine triphosphatase(ITPA), which vary between ethnic groups. Moreover, MTX toxicity is associated with polymorphisms in genes encoding solute carrier organic anion transporter family member 1B1(SLCO1B1) and dihydrofolate reductase(DHFR). Additional polymorphisms potentially associated with toxicities for MTX have also been identified, including those in the genes encoding solute carrier family 19 member 1(SLC19A1)and thymidylate synthetase(TYMS), but their contributions have not yet been well quantified. It is clear that pharmacogenomics should be incorporated as a dosage-calibrating tool in pediatric ALL treatment in order to predict and minimize the occurrence of serious toxicities for these patients.     

Chemotaxonomic implications of the absence of sesquiterpene lactones in Grazielia multifida (DC.) R.M.King & H.Rob. (Asteraceae)

The phytochemical investigation of Grazielia multifida aerial parts yielded eight compounds, including four ent-kaurenic acid diterpenes derivatives, 15-tiglinoyloxy-ent-kaur-16-en-19-oic acid (1), 15-hydroxy-ent-kaur-16-en-19-oic acid (2), 17-hydroxy-ent-kaur-15-en-19-oic acid (3) and 15-isovaleroyloxy-ent-kaur-16-en-19-oic acid (4), one amino acid, tryptophan (5), and three flavonoids, eupafolin (6), guaijaverin (7) and quercitrin (8). The structures of the isolated compounds were established based on analysis of their spectroscopic data and comparison with literature. All the compounds were isolated from this species for the first time. The chemotaxonomic significance of the absence of sesquiterpene lactones in G. multifida has also been summarized.     

Turnover of Sex Chromosomes in the Stickleback Fishes (Gasterosteidae)

Diverse sex-chromosome systems are found in vertebrates, particularly in teleost fishes, where different systems can be found in closely related species. Several mechanisms have been proposed for the rapid turnover of sex chromosomes, including the transposition of an existing sex-determination gene, the appearance of a new sex-determination gene on an autosome, and fusions between sex chromosomes and autosomes. To better understand these evolutionary transitions, a detailed comparison of sex chromosomes between closely related species is essential. Here, we used genetic mapping and molecular cytogenetics to characterize the sex-chromosome systems of multiple stickleback species (Gasterosteidae). Previously, we demonstrated that male threespine stickleback fish (Gasterosteus aculeatus) have a heteromorphic XY pair corresponding to linkage group (LG) 19. In this study, we found that the ninespine stickleback (Pungitius pungitius) has a heteromorphic XY pair corresponding to LG12. In black-spotted stickleback (G. wheatlandi) males, one copy of LG12 has fused to the LG19-derived Y chromosome, giving rise to an X₁X₂Y sex-determination system. In contrast, neither LG12 nor LG19 is linked to sex in two other species: the brook stickleback (Culaea inconstans) and the fourspine stickleback (Apeltes quadracus). However, we confirmed the existence of a previously reported heteromorphic ZW sex-chromosome pair in the fourspine stickleback. The sex-chromosome diversity that we have uncovered in sticklebacks provides a rich comparative resource for understanding the mechanisms that underlie the rapid turnover of sex-chromosome systems.     

A new flavone glycoside from the leaves of Agastache rugosa (Fisch. & C.A.Mey.) Kuntze

Agastache rugosa (Fisch. & C.A.Mey.) Kuntze has been widely used as a food spice and a remedy for colds in Korea, China and Japan. In this study, one new flavone glycoside (1) along with six flavonoids (2–7), nine phenyl glycosides (8–16) and three megastigmane glycosides (17–19) were isolated from the leaves of A. rugosa. By extensive spectroscopic methods including 1D and 2D NMR, and MS data, the structure of the new compound (1) was elucidated as acacetin 7-O-β-(6″-(E)-crotonylglucopyranoside). From present investigation, compound 1 and 7–19 were isolated for the first time from the genus Agastache and 1, 16, 18 and 19 in the Lamiaceae family.     

Mutations affecting the mitochondrial genes encoding the cytochrome oxidase subunit I and apocytochrome b of Chlamydomonas reinhardtii

Mitochondrial mutants of the green alga Chlamydomonas reinhardtii that are inactivated in the cytochrome pathway of respiration have previously been isolated. Despite the fact that the alternative oxidase pathway is still active the mutants have lost the capacity to grow heterotrophically (dark + acetate) and display reduced growth under mixotrophic conditions (light + acetate). In crosses between wild-type and mutant cells, the meiotic progeny only inherit the character transmitted by the mt ^? parent, which indicates that the mutations are located in the 15.8 kb linear mitochondrial genome. Two new mutants (dum-18 and dum-19) have now been isolated and characterized genetically, biochemically and at the molecular level. In addition, two previously isolated mutants (dum-11 and dum-15) were characterized in more detail. dum-11 contains two types of deleted mitochondrial DNA molecules: 15.1 kb monomers lacking the subterminal part of the genome, downstream of codon 147 of the apocytochrome b (COB) gene, and dimers resulting from head-to-head fusion of asymmetrically deleted monomers (15.1 and 9.5 kb DNA molecules, respectively). As in the wild type, the three other mutants contain only 15.8 kb mitochondrial DNA molecules. dum-15 is mutated at codon 140 of the COB gene, a serine (TCT) being changed into a tyrosine (TAC). dum-18 and dum-19 both inactivate cytochrome c oxidase, as a result of frameshift mutations (addition or deletion of 1 bp) at codons 145 and 152, respectively, of the COX1 gene encoding subunit I of cytochrome c oxidase. In a total of ten respiratory deficient mitochondrial mutants characterized thus far, only mutations located in COB or COXI have been isolated. The possibility that the inactivation of the other mitochondrial genes is lethal for the cells is discussed.     

Actin depolymerizing effect of trisoxazole-containing macrolides

Oxazole-containing macrolides (1-5) isolated from the marine sponge Chondrosia corticata were evaluated for their actin depolymerizing activities by monitoring fluorescent intensity of pyrene F-actin. These studies led to the identification of (19Z)-halichondramide (5) as a new actin depolymerizing agent. The actin depolymerizing activity by (19Z)-halichondramide (5) was four times more potent than that of halichondramide (1). Compounds 1 and 5 also have potent antifungal activity. The preliminary structure-activity relationship of these compounds is described to elucidate the essential structural requirements.     

Substrate specificity of the epoxidation reaction in sex pheromone biosynthesis of the Japanese giant looper (Lepidoptera: Geometridae)

Female moths of the Japanese giant looper (Ascotis selenaria cretacea, Lepidoptera: Geometridae) secrete (Z,Z)-6,9-cis-3,4-epoxynonadecadiene as a sex pheromone component. To the pheromone glands of the decapitated females, [19,19,19-D₃](Z,Z,Z)-3,6,9-nonadecatriene was applied after an injection of pheromone biosynthesis activating neuropeptide. GC-MS analysis of the gland extract showed its specific conversion into the pheromonal cis-3,4-epoxide indicating that the C₁₉ triene which had been identified in the gland was a precursor of the pheromone. In order to examine the substrate specificity of the enzyme catalyzing this epoxidation step, several unsaturated hydrocarbons not occurring in the gland were applied to it. Not only (Z,Z,Z)-3,6,9-trienes with varying chain lengths (C₁₇, C₁₈ and C₂₀ to C₂₂) but (Z,Z)-3,6-dienes (C₁₇, C₁₉ and C₂₀) were converted into the corresponding cis-3,4-epoxides in a rather good yield, while no 6,7- and 9,10-epoxides could be detected. (Z)-3-Nonadecene was also changed to the cis-epoxide, but (E)-3-, (Z)-2- and (Z)-4-double bonds in the C₁₉ chain were not oxidized. These in vivo experiments revealed that the monooxygenase regiospecifically attacked the (Z)-3-double bond of straight chain hydrocarbons regardless of their length and degree of unsaturation.     

Lithobius (Monotarsobius) zhangi sp. n., a new species from Eastern China (Chilopoda,Lithobiomorpha, Lithobiidae)

Lithobius (Monotarsobius) zhangi sp. n. (Lithobiomorpha: Lithobiidae), recently discovered from Nanshan Park, Yantai City, Shandong Province, and Wuyishan County, Nanping City, Fujian Province, from China, is described. Morphologically it resembles Lithobius (Monotarsobius) songi Pei, Ma, Shi, Wu, Zhou, 2011 from Province Hebei, China, but can be readily distinguished from the latter by antennae composed of 15+15–19+19 articles versus 19+19–21+21 articles, terminal claw of female gonopods inner tooth broader than the outer vs dorsal and ventral tooth about same in size, ventral plectrotaxy 01320, dorsal plectrotaxy 10210 in the 14th legs, 01210 and 10200 respectively in Lithobius (Monotarsobius) songi. A key to the Lithobius (Monotarsobius) species of China and Korea is presented.     

Anti-inflammatory constituents from the fruits of Vitex rotundifolia

Three new diterpenes (7, 15 and 17) and two new neolignans (19 and 20) along with nineteen known compounds have been isolated from the fruits of Vitex rotundifolia. Their structures were elucidated by a combination of 1D and 2D NMR, HRESI-MS, and CD data. All isolates were tested for their inhibitory activities on LPS-induced nitric oxide production in RAW264.7 cells. Of these, compounds 3, 4, 7, 13, 15, 19, and 24 found to inhibit nitric oxide production with the IC₅₀ values ranging from 11.3 to 24.5 μM.     

The discovery and phylogenetic implications of a novel 41 bp plastid DNA deletion in wild potatoes

Insertions and deletions (indels) are common in intergenic spacer regions of plastid DNA and can provide important phylogenetic characters for closely related species. For example, a 241-bp plastid DNA deletion in the trnV-UAC/ndhC intergenic spacer region has been shown to have major phylogenetic importance in determining the origin of the cultivated potato. As part of a phylogenetic study of the wild potato Solanum series Piurana group we screened 199 accessions of 38 wild potato species in nine of the 19 tuber-bearing (Solanum section Petota) series that have not been examined before for indels in the trnV-UAC/ndhC intergenic spacer region. A novel 41 bp deletion (but no 241 bp deletion) was discovered for 30 accessions of three species: S. chiquidenum (5 of 10 accessions), S. chomatophilum (19 of 28), and S. jalcae (6 of 6). Accessions with and without this deletion are found throughout much of the north-south range of all three species in northern and central Peru, but not east of the Marañón River. Multivariate morphological analyses of these 44 accessions showed no morphological associations to the deletion. The results suggest extensive interspecific gene flow among these three species, or a common evolutionary history among species that have never been suggested to be interrelated.     

Evolutionary aspects of a unique internal mitochondrial targeting signal in nuclear-migrated rps19 of sugar beet (Beta vulgaris L.)

The endosymbiotic theory postulates that many genes migrated from endosymbionts to the nuclear genomes of their hosts. Some migrated genes lack presequences directing proteins to mitochondria, and their mitochondrial targeting signals appear to be inscribed in the core coding regions as internal targeting signals (ITSs). ITSs may have evolved after sequence transfer to nuclei or ITSs may have pre-existed before sequence transfer. Here, we report the molecular cloning of a sugar beet gene for ribosomal protein S19 (Rps19; the first letter is capitalized when the gene is a nuclear gene). We show that sugar beet Rps19 (BvRps19) is an ITS-type gene. Based on amino-acid sequence comparison, dicotyledonous rps19s (the first letter is lower-cased when the gene is a mitochondrial gene), such as tobacco rps19 (Ntrps19), resemble an ancestral form of BvRps19. We investigated whether differences in amino-acid sequences between BvRps19 and Ntrps19 were involved in ITS evolution. Analyses of the intracellular localization of chimaeric GFP-fusion proteins that were transiently expressed in Welsh onion cells showed that Ntrps19-gfp was not localized in mitochondria. When several BvRps19-type amino acid substitutions, none of which was seen in any other angiosperm rps19, were introduced into Ntrps19-gfp, the modified Ntrps19-gfp became localized in mitochondria, supporting the notion that an ITS in BvRps19 evolved following sequence transfer to nuclei. Not all of these substitutions were seen in other ITS-type Rps19s, suggesting that the ITSs of Rps19 are diverse.     

Metabolism of 25-hydroxyvitamin D3 by rat kidney cells in culture: Isolation and identification of cis- and trans-19-nor-10-oxo-25-hydroxyvitamin D3

A primary confluent culture of epithelial cells from rat kidney has been developed. These cells possess a 3.2–3.4 S high-affinity, low-capacity binding protein for 1,25-dihydroxyvitamin D₃. They metabolize 25-hydroxyvitamin D₃ to at least five metabolites. Two have been identified as 1,25-dihydroxyvitamin D₃ and 24,25-dihydroxyvitamin D₃. Two others have been identified by means of physical data and cochromatography as trans 19-nor-10-oxo-25-hydroxyvitamin D₃ and the other as its cis isomer. These two “metabolites” have not been observed in vivo, but one of them (cis) comigrates with 1,25-dihydroxyvitamin D₃ on straight-phase high-performance liquid chromatography. Thus, mere cochromatography on high-performance liquid chromatography is not sufficient to identify critical vitamin D metabolites.