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1.
Paramesopsocus lu n. gen., n. sp. and Paramesopsocus adibi n. sp. are respectively described from the Early Cretaceous amber of Lebanon and from the Late Jurassic limestone of Karatau (Kazakhstan). They are placed within the suborder Psocomorpha, and in the Mesozoic extinct family Paramesopsocidae n. fam. A cladistic phylogeny for Psocomorpha is given including our fossil taxa. The discovery of these new taxa demonstrates the necessity of a deep cladistic redefinition of the currently admitted major subdivisions of this suborder.  相似文献   

2.
Organisms Diversity & Evolution - The paper continues the exploration of the morphological and functional diversity of male genitalia in Archaeognatha by the study of an undescribed...  相似文献   

3.
Jere Kahanp?? 《ZooKeys》2014,(441):183-207
An updated checklist of the Atelestidae, Brachystomatidae, Dolichopodidae, Empididae and Hybotidae (Diptera) recorded from Finland is presented. The genera with uncertain placement within superfamily Empidoidea (= the Iteaphila group) are also included in this paper.  相似文献   

4.
Jere Kahanp?? 《ZooKeys》2014,(441):213-223
A checklist of the Lonchopteridae and Phoridae recorded from Finland is presented.  相似文献   

5.
The mitochondrial calcium uniporter (MCU) is responsible for mitochondrial calcium uptake and homeostasis. It is also a target for the regulation of cellular anti‐/pro‐apoptosis and necrosis by several oncogenes and tumour suppressors. Herein, we report the crystal structure of the MCU N‐terminal domain (NTD) at a resolution of 1.50 Å in a novel fold and the S92A MCU mutant at 2.75 Å resolution; the residue S92 is a predicted CaMKII phosphorylation site. The assembly of the mitochondrial calcium uniporter complex (uniplex) and the interaction with the MCU regulators such as the mitochondrial calcium uptake‐1 and mitochondrial calcium uptake‐2 proteins (MICU1 and MICU2) are not affected by the deletion of MCU NTD. However, the expression of the S92A mutant or a NTD deletion mutant failed to restore mitochondrial Ca2+ uptake in a stable MCU knockdown HeLa cell line and exerted dominant‐negative effects in the wild‐type MCU‐expressing cell line. These results suggest that the NTD of MCU is essential for the modulation of MCU function, although it does not affect the uniplex formation.  相似文献   

6.
Free fatty acids (FFAs) acutely stimulate insulin secretion from pancreatic β-cells, whereas impair β-cell function following long term exposure. GPR40, a FFAs receptor, has been demonstrated to be activated by both medium and long chain FFAs and played an important role in insulin release. This study was performed to determine the contribution of GPR40 to short- and/or long-term effects of FFAs on glucose-stimulated insulin secretion (GSIS) and the expression of PDX-1 and GLUT2 in pancreatic β-cells, as well as the intervenient effects of pioglitazone on lipotoxicity of β-cells. βTC6 cell line stably expressing GPR40shRNA were established and the intervention of FFAs and pioglitazone on GSIS and expression of PDX-1 and GLUT2 in βTC6 cells was investigated. Results showed that 1-h exposure to FFAs significantly enhanced GSIS and increased expression of PDX-1 and GLUT2 in pSilencer-control transfected cells, but not in cells transfected with GPR40shRNA. While 48-h exposure to FFAs significantly impaired GSIS in pSilencer-control transfected cells as well as cells transfected with GPR40shRNA. Furthermore, pioglitazone enhanced insulin secretion in pSilencer-control transfected cells exposed to FFAs for 48 h, but not in cells transfected with GPR40shRNA. These results indicate that GPR40 mediates the short-term effects of FFAs on GSIS, but does not mediate the chronic lipotoxicity on β-cells. The reverse role of pioglitazone on lipotoxicity of β-cells may be related to GPR40.  相似文献   

7.
We have purified haemoglobin Philly by isoelectric focusing on polyacrylamide gel, and studied its oxygen equilibrium, proton nuclear magnetic resonance spectra, mechanical stability, and pH-dependent u.v. difference spectrum. Stripped haemoglobin Philly binds oxygen non-co-operatively with high affinity. Inorganic phosphate and 2,3-diphosphoglycerate have little effect on the equilibrium curve, but inositol hexaphosphate lowers the affinity and induces co-operativity. These properties are explained by the nuclear magnetic resonance spectra which show that stripped deoxyhaemoglobin Philly has the quaternary oxy structure and that inositol hexaphosphate converts it to the deoxy structure. An exchangeable proton resonance at ?8.3 p.p.m. from water, which is present in oxy- and deoxyhaemoglobin A, is absent in both these derivatives of haemoglobin Philly and can therefore be assigned to one of the hydrogen bonds made by tyrosine C1-(35)β, probably the one to aspartate H8(126)α at the α1β1 contact. Haemoglobin Philly shows the same pH-dependent u.v. difference spectrum as haemoglobin A, only weaker, so that a tyrosine other than 35β must be mainly responsible for this.  相似文献   

8.
Protein kinase A (PKA) exists as several tissue-specific isoforms that through phosphorylation of serine and threonine residues of substrate proteins act as key regulators of a number of cellular processes. We here demonstrate that the human sperm-specific isoform of PKA named Cα2 is important for sperm motility and thus male fertility. Furthermore, we report on the first three-dimensional crystal structure of human apo Cα2 to 2.1 ?. Apo Cα2 displays an open conformation similar to the well-characterized apo structure of murine Cα1. The asymmetric unit contains two molecules and the core of the small lobe is rotated by almost 13° in the A molecule relative to the B molecule. In addition, a salt bridge between Lys72 and Glu91 was observed for Cα2 in the apo-form, a conformation previously found only in dimeric or ternary complexes of Cα1. Human Cα2 and Cα1 share primary structure with the exception of the amino acids at the N-terminus coded for by an alternative exon 1. The N-terminal glycine of Cα1 is myristoylated and this aliphatic chain anchors the N-terminus to an intramolecular hydrophobic pocket. Cα2 cannot be myristoylated and the crystal structure revealed that the equivalent hydrophobic pocket is unoccupied and exposed. Nuclear magnetic resonance (NMR) spectroscopy further demonstrated that detergents with hydrophobic moieties of different lengths can bind deep into this uncovered pocket. Our findings indicate that Cα2 through the hydrophobic pocket has the ability to bind intracellular targets in the sperm cell, which may modulate protein stability, activity and/or cellular localization.  相似文献   

9.
A checklist of 112 species of shore flies (Ephydridae, Diptera) recorded from Finland is presented. Comparing this to the list of Hackman (1980), 52 changes are made: 25 species are added (all but one recorded after 1980), 18 misidentifications are deleted, 5 junior synonyms are replaced and 5 updated generic combinations are given.  相似文献   

10.
11.
A revised checklist of the Scathophagidae, Fanniidae and Muscidae recorded from Finland is presented. Phaonia amicula Villeneuve, 1922 is noted from Finland for the first time.  相似文献   

12.
13.
Structure and function of xanthine oxidoreductase: where are we now?   总被引:23,自引:0,他引:23  
Xanthine oxidoreductase (XOR) is a complex molybdoflavoenzyme, present in milk and many other tissues, which has been studied for over 100 years. While it is generally recognized as a key enzyme in purine catabolism, its structural complexity and specialized tissue distribution suggest other functions that have never been fully identified. The publication, just over 20 years ago, of a hypothesis implicating XOR in ischemia-reperfusion injury focused research attention on the enzyme and its ability to generate reactive oxygen species (ROS). Since that time a great deal more information has been obtained concerning the tissue distribution, structure, and enzymology of XOR, particularly the human enzyme. XOR is subject to both pre- and post-translational control by a range of mechanisms in response to hormones, cytokines, and oxygen tension. Of special interest has been the finding that XOR can catalyze the reduction of nitrates and nitrites to nitric oxide (NO), acting as a source of both NO and peroxynitrite. The concept of a widely distributed and highly regulated enzyme capable of generating both ROS and NO is intriguing in both physiological and pathological contexts. The details of these recent findings, their pathophysiological implications, and the requirements for future research are addressed in this review.  相似文献   

14.
Batch culture experiments using viral enrichment were conducted to test the response of a coastal bacterial community to autochthonous (i.e., co-existing) or allochthonous riverine viruses. The effects of viral infections on bacterial dynamics and activity were assessed by epifluorescence microscopy and thymidine incorporation, respectively, whereas the effect of viral infection on bacterial community composition was examined by polymerase chain reaction-single strand conformation polymorphism 16S ribosomal RNA fingerprinting. The percentages of high nucleic acid-containing cells, evaluated by flow cytometry, were significantly correlated (r 2 = 0.91, n = 12, p < 0.0001) to bacterial production, making this value a good predictor of active cell dynamics along the study. While confinement and temperature were the two principal experimental factors affecting bacterial community composition and dynamics, respectively, additions of freshwater viruses had significant effects on coastal bacterial communities. Thus, foreign viruses significantly reduced net bacterial population increase as compared to the enrichment treated with inactivated virus. Moreover, freshwater viruses recurrently and specifically affected bacterial community composition, as compared to addition of autochthonous viruses. In most cases, the combined treatment viruses and freshwater dissolved organic matter helped to maintain or even enhance species richness in coastal bacterial communities in agreement to the ‘killing the winner’ hypothesis. Thus, riverine virus input could potentially influence bacterial community composition of the coastal bay albeit with modest modification of bulk bacterial growth. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

15.
Annitella apfelbecki is one of three Annitella species with distribution ranges restricted to the Balkan Peninsula. In this paper, we describe the hitherto unknown female of A. apfelbecki and give the most important morphological features to enable its identification and separation from the other Annitella females. Additionally, we provide new data on distribution and discuss zoogeography, life cycle and ecology of this species.  相似文献   

16.
Kambiz Minaei 《ZooKeys》2013,(330):53-74
In Iran, as a result of recent changes in nomenclature 201 species and one species group of the insect Order Thysanoptera, are here listed in 70 genera and five families. In considering species listed previously from this country, the presence of 7 species is considered not confirmed, and 12 species are excluded from the Iranian list. Problems in the study of Iranian Thysanoptera are discussed briefly.  相似文献   

17.
In humans we know 25 selenoproteins that play important roles in redox regulation, detoxification, immune-system protection and viral suppression. In particular, selenoprotein M (SelM) may function as thiol disulfide oxidoreductase that participates in the formation of disulfide bonds, and can be implicated in calcium responses. However, it presents a redox motif (CXXU), where U is a selenocysteine, and may also function as redox regulator because its decreased or increased expression regulated by dietary selenium alters redox homeostasis. No data are reported in literature about its involvement in cancer but only in neurodegenerative diseases. In this paper we evaluated the SelM expression in two hepatoma cell lines, HepG2 and Huh7, compared to normal hepatocytes. The results suggested its involvement in hepatocellular carcinoma (HCC) as well as its possible use to follow the progression of this cancer as putative marker. The aim of this study has been to analyze the structure–function relationships of SelM. Hence, firstly we studied the evolutionary history of this protein by phylogenetic analysis and GC content of genes from various species. So, we modeled the three-dimensional structure of the human SelM evaluating its energetic stability by molecular dynamics simulations. Moreover, we modeled some of its mutants to obtain structural information helpful for structure-based drug design.  相似文献   

18.
Stringent response is a pleiotropic physiological response of cells caused by deficiency of aminoacetylated tRNAs and, correspondingly, by the arrest of protein synthesis. This response can experimentally be induced by amino acid deficiency in a culture medium and limitation of the aminoacylation capacity of tRNA molecules even in the presence of the respective amino acids in the cell. Many traits of this response indicate its dependence on the accumulation of ppGpp molecules. There are links between the growth rate of actinomycetes and the biosynthesis of secondary metabolites by the bacteria. In particular, it has been established that the introduction of additional relA gene copies of the ppGpp synthetase can affect the production of antibiotics in streptomycetes. The survey presents the authors’ own experimental data obtained in the studies on the effect of heterologous relA gene expression in Streptomyces nogalater, the nogalamycin producer.  相似文献   

19.
Since 2005, the Florida citrus industry has faced the need to control the devasting bacterial disease huanglongbing (HLB). Advanced production systems (APS) were designed to grow citrus trees more quickly than conventional citriculture (CC) methods in order to mitigate the impact of HLB. Daily fertigation required by APS produces changes in the soil physical–chemical properties compared to those in conventionally managed orchards. We used real-time PCR in an ongoing field experiment to compare the effects of APS and CC on more than a dozen metazoan and microorganism species in soil food webs that affect larvae of a major arthropod pest of citrus, Diaprepes abbreviatus. Soil chemical properties, citrus performance, weevil occurrence, and abundance of free-living and plant-parasitic nematodes were also evaluated. The effects of polypropylene mulch that provides a barrier to soil entry by D. abbreviatus larvae were also investigated in each of the two cultural systems. Trees grew significantly larger in APS and mulching increased tree growth and reduced tree mortality, thereby increasing fruit yield per ha. APS increased the fruit yield in 2011; however, by 2013 the number of fruit per tree was not affected by any of the treatments. Root mass density increased in APS, but decreased under mulch. The numbers of plant-parasitic and free-living nematodes and some natural enemies of nematodes such as Catenaria sp. and Paecilomyces lilacinus were more abundant in the treatments with greater root mass density. Both organisms in the D. abbreviatusPhytophthora nicotianae pest–disease complex were more abundant in APS than in CC, whereas fewer steinernematid entomopathogenic nematodes (EPNs) that prey on insect larvae occurred in APS. By contrast, heterorhabditid EPNs tended to be more numerous in APS than in CC, although they comprised <25% of the EPN communities in any treatment. Major differences between APS and CC in almost all of the measured physical and chemical soil properties provide a basis for controlled studies to understand why EPN taxa responded differently to these treatments and how APS and soils generally might be modified to conserve the beneficial activities of nematodes.  相似文献   

20.
The (25R)- and (25S)-epimers of C27 3α,7α,12α-trihydroxy-5α-cholestan-27-oic acid as well as their corresponding N-acylamidate conjugates with glycine or taurine were prepared starting from cholic acid in 14 steps. The principal reactions involved were (1) reduction of a key intermediary C24allo-cholic acid performate with NaBH4/triethylamine/ethyl chloroformate, (2) iodination of the resulting 3,7,12-triformyloxy-5α-cholan-24-ol with I2/triphenylphosphine; (3) nucleophilic substitution of the iodo derivative with diethylmethyl malonate/NaH; and (4) hydrolysis of the resulting 3,7,12-triformyloxy-25-methyl-26,27-diethyl ester with KOH, followed by decarboxylation of the geminal dicarboxylic acid with LiCl. N-Acylamidation of the resulting (25R)/(25S)-3α,7α,12α-trihydroxy-5α-cholestan-27-oic acid mixture with glycine or taurine afforded the corresponding epimeric mixtures of the glycine and taurine conjugates. The (25R)- and (25S)-epimers of the three variants of unconjugated and conjugated 3α,7α,12α-trihydroxy-5α-cholestan-27-oic acid were efficiently separated by HPLC on a reversed-phase C18 column and their structural characteristics, particularly the chiral center at C-25, delineated using 1H and 13C NMR. These synthetic compounds should be useful as authentic reference standards for establishing their presence in bile as well as being useful in studies on the biosynthesis of allo-bile acids from cholesterol.  相似文献   

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