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1.
A new needle nematode, Longidorus carniolensissp. n., recovered from the soil around the roots of grapevine Vitis vinifera L. from Slovenia, is described and illustrated. Longidorus carniolensisis an amphimictic species, characterised by females with a moderately long (L=5.6-8.2 mm) and plump (a=51-72.4, ave. 66.3) body, assuming a spiral to C-shape when heat relaxed. Head region continuous, anteriorly almost flat, lip region 23-25 μm wide; guiding ring situated posteriorly (42-47 μm, 43-50 μm in males), odontostyle long (ave. 146.6 (136-157) μm); pharyngeal glands with normal location, their nuclei of approximately equal size; tail bluntly conoidal to almost hemispherical. Males abundant, spicules slender and long (122-145 μm), ventromedian supplements 13-17, irregularly spaced, preceded by an adanal pair. Four juvenile stages present, the first stage juvenile with bluntly conoidal tail. Codes for identifying the new species when using the key by Chen et al. (1997) are: A 56, B 4, C 4, D 1, E 4, F 35, G 1, H 1, I 2. The new species is morphologically the most similar to Longidorus poessneckensis Altherr, 1974, Longidorus macrosoma Hooper, 1961, Longidorus caespiticola Hooper, 1961, Longidorus helveticus Lamberti et al., 2001, Longidorus macroteromucronatus Altherr, 1974, Longidorus pius Barsi & Lamberti, 2001, Longidorus raskii Lamberti & Agostinelli, 1993, Longidorus kheirii Pedram et al. 2008, Longidorus silvae Roca, 1993, Longidorus iuglandis Roca et al., 1985, Longidorus vinearum Bravo & Roca, 1995 and Longidorus major Roca & d'Erico, 1987, but differs from these species either by the body and odontostyle length, position of guide ring, head region and tail shape or the shape of the first stage juvenile tail. Sequence data from the D2-D3 region of the 28S rDNA distinguishes this new species from other speciesof the genus Longidorus with known sequences. Relationships of Longidorus carniolensissp. n. with other Longidorus species based on analysis of this DNA fragment and morphology are discussed.  相似文献   
2.
We assessed the feasibility of fetal RHD and RHCE genotyping by analysis of DNA extracted from plasma samples of RhD-negative pregnant women using real-time PCR and primers and probes targeted toward RHD and RHCE genes. We analyzed 45 pregnant women in the 11th to 40th weeks of pregnancy and correlated the results with serological analysis of cord blood after delivery. Non-invasive prenatal fetal RHD exon 7, RHD exon 10, RHCE exon 2 (C allele), and RHCE exon 5 (E allele) genotyping analysis of maternal plasma samples was correctly performed in 45 out of 45 RhD-negative pregnant women delivering 24 RhD-, 17 RhC-, and 7 RhE-positive newborns. Detection of fetal RHD and the C and E alleles of RHCE gene from maternal plasma is highly accurate and enables implementation into clinical routine. We recommend performing fetal RHD and RHCE genotyping together with fetal sex determination in alloimmunized D-negative pregnancies at risk of hemolytic disease of the newborn. In case of D-negative fetus, amplification of another paternally inherited allele (SRY and/or RhC and/or RhE positivity) proves the presence of fetal DNA in maternal circulation.  相似文献   
3.
The taxonomic position of two antarctic dorylaimid species Amblydorylaimus isokaryon (Loof, 1975) Andrássy, 1998 and Pararhyssocolpus paradoxus (Loof, 1975), gen. n., comb. n. are discussed on the basis of morphological, including SEM study, morphometric, postembryonic and sequence data of 18S rDNA and the D2-D3 expansion fragments of large subunit rDNA. The evolutionary trees inferred from 18S sequences show insufficient resolution to determine the assignment of the two species to particular families, moreover Pararhyssocolpus paradoxus gen. n., comb. n. (=Rhyssocolpus paradoxus) previously regarded as a member of Nordiidae or Qudsianematidae, showed distant relationship both to Rhyssocolpus vinciguerrae and Eudorylaimus spp. The phylogram inferred from 28S sequences revealed that Amblydorylaimus isokaryon is a member of a well-supported group comprised of several Aporcelaimellus spp., while, no close relationships could be revealed for the Pararhyssocolpus paradoxus gen. n., comb. n. to any nematode genus. On the basis of molecular data and morphological characteristics, some taxonomic changes are proposed. Amblydorylaimus isokaryon is transferred from family Qudsianematidae to family Aporcelaimidae, and a new monotypic genus Pararhyssocolpus gen. n. is proposed, attributed to Pararhyssocolpidae fam. n. The diagnosis of the new family is provided together with emended diagnosis of the genera Amblydorylaimus and Pararhyssocolpus gen. n. Data concerning distribution of these endemic genera in the Antarctic region are also given.  相似文献   
4.
5.
In the present study, some new analogues of VV-hemorphin-5, modified at position 1 and 7 by the non-proteinogenic and/or natural amino acids followed the structures Xxx-Val-Val-Tyr-Pro-Trp-Thr-Gln-NH2 and Val-Val-Tyr-Pro-Trp-Thr-Yyy-NH2, where Xxx is Ile or Aib and Yyy is Lys/Orn/Dap/Dab were synthesized to investigate their potential antinociceptive activities. We report also the redox potentials and the acid/base properties as pKa values of these peptide analogues which were compared toward electrochemical behaviour of tryptophan containing peptides. All analogues showed a short lasting initial antinociceptive effect, however H2 hemorphin analogue is characterized with prolong and strong antinociceptive effect, while the other peptide analogues exerted more variable effects on the visceral nociception depending on the dose or time after the intracerebral injection.  相似文献   
6.
During gestation there is a high demand for the essential nutrient choline. Adult rats supplemented with choline during embryonic days (E) 11-17 have improved memory performance and do not exhibit age-related memory decline, whereas prenatally choline-deficient animals have memory deficits. Choline, via betaine, provides methyl groups for the production of S-adenosylmethionine, a substrate of DNA methyltransferases (DNMTs). We describe an apparently adaptive epigenomic response to varied gestational choline supply in rat fetal liver and brain. S-Adenosylmethionine levels increased in both organs of E17 fetuses whose mothers consumed a choline-supplemented diet. Surprisingly, global DNA methylation increased in choline-deficient animals, and this was accompanied by overexpression of Dnmt1 mRNA. Previous studies showed that the prenatal choline supply affects the expression of multiple genes, including insulin-like growth factor 2 (Igf2), whose expression is regulated in a DNA methylation-dependent manner. The differentially methylated region 2 of Igf2 was hypermethylated in the liver of E17 choline-deficient fetuses, and this as well as Igf2 mRNA levels correlated with the expression of Dnmt1 and with hypomethylation of a regulatory CpG within the Dnmt1 locus. Moreover, mRNA expression of brain and liver Dnmt3a and methyl CpG-binding domain 2 (Mbd2) protein as well as cerebral Dnmt3l was inversely correlated to the intake of choline. Thus, choline deficiency modulates fetal DNA methylation machinery in a complex fashion that includes hypomethylation of the regulatory CpGs within the Dnmt1 gene, leading to its overexpression and the resultant increased global and gene-specific (e.g. Igf2) DNA methylation. These epigenomic responses to gestational choline supply may initiate the long term developmental changes observed in rats exposed to varied choline intake in utero.  相似文献   
7.
We report sphingolipid-related reorganization of gel-like microdomains in the plasma membrane of living Saccharomyces cerevisiae using trans-Parinaric acid (t-PnA) and 1,6-diphenyl-1,3,5-hexatriene (DPH). Compared to control, the gel-like domains were significantly reduced in the membrane of a sphingolipid-deficient lcb1-100 mutant. The same reduction resulted from sphingolipid depletion by myriocin. The phenotype could be reverted when a myriocin-induced block in sphingolipid biosynthesis was bypassed by exogenous dihydrosphingosine. Lipid order of less-ordered membrane regions decreased with sphingolipid depletion as well, as documented by DPH fluorescence anisotropy. The data indicate that organization of lateral microdomains is an essential physiological role of these structural lipids.  相似文献   
8.
In F2 hybrids between self-sterile plants of the Volkhova cultivar and self-fertile lines with established self-fertility mutations (sf mutations) at the major incompatibility loci S (1R), Z (2R), and T (5R), the effect of sf mutations on the inheritance of secalin-encoding, isozyme, and morphological markers located on the same chromosomes was investigated. Linkage between loci Prx7 and Sand locus Sec3 coding for high-molecular-weight secalins on chromosome 1R was shown for the first time. The frequency of recombination between Prx7andSec3and between S and Sec3was 29.1 ± 4.8% and 30.9 ± 7.0%, respectively. Independent inheritance of locus Z and isozyme markers of chromosome 2R, Est3/5 and -Glu, from locus Sec2 encoding 75-kDa -secalins was shown; in hybrids, the recombination frequency between Est3/5 and locus Z varied from 19.2 ± 8.1 to 50%. Independent inheritance of morphological (Ddw and Hs) and isozyme markers (Est4, Est6/9,and Aco2) of chromosome 5R from locus Tlocated on the same chromosome was demonstrated.  相似文献   
9.
We have previously reported a method for isolation of mutants with enhanced tolerance to the fungal AAL toxin and given a detailed characterization of atr1 (AAL toxin resistant, Gechev et al. in Biochem Biophys Res Commun 375:639–644, 2008). Herewith, we report eight more mutants with enhanced tolerance to the AAL toxin. Phenotypic analysis showed that six of the mutants were reduced in size compared with their original background loh2. Furthermore, atr2 showed delayed flowering and senescence. The mutants were also evaluated for oxidative stress tolerance by growing them on ROS-inducing media supplemented with either aminotriazole or paraquat, generating, respectively, H2O2 or superoxide radicals. Oxidative stress, confirmed by induction of the marker genes, HIGH AFFINITY NITRATE TRANSPORTER At1G08090 and HEAT SHOCK PROTEIN 17 At3G46230, inhibited growth of all lines. However, while the original background loh2 developed necrotic lesions and died rapidly on ROS-inducing plant growth media, atr1, atr2, atr7 and atr9 remained green and viable. The tolerance against oxidative stress-induced cell death was confirmed by fresh weight and chlorophyll measurements. Real-time PCR analysis revealed that the expression of the EXTENSIN gene At5G46890, previously shown to be downregulated by aminotriazole in atr1, was repressed in all lines, consistent with the growth inhibition induced by oxidative stress. Taken together, the data indicate a complex link between growth, development and oxidative stress tolerance and indicates that growth inhibition can be uncoupled from oxidative stress-induced cell death.  相似文献   
10.

Background

The role of intra- and extra-cranial venous system impairment in the pathogenesis of various vascular, inflammatory and neurodegenerative neurological disorders, as well as in aging, has not been studied in detail. Nor have risk factors been determined for increased susceptibility of venous pathology in the intra-cranial and extra-cranial veins. The aim of this study was to investigate the association between presence of a newly proposed vascular condition called chronic cerebrospinal venous insufficiency (CCSVI) and environmental factors in a large volunteer control group without known central nervous system pathology.

Methods and Findings

The data were collected in a prospective study from 252 subjects who were screened for medical history as part of the entry criteria and participated in the case-control study of CCSVI prevalence in multiple sclerosis (MS) patients, and then were analyzed post-hoc. All participants underwent physical and Doppler sonography examinations, and were assessed with a structured environmental questionnaire. Fullfilment of ≥2 positive venous hemodynamic (VH) criteria on Doppler sonography was considered indicative of CCSVI diagnosis. Risk and protective factors associated with CCSVI were analyzed using logistic regression analysis. Seventy (27.8%) subjects presented with CCSVI diagnosis and 153 (60.7%) presented with one or more VH criteria. The presence of heart disease (p = .001), especially heart murmurs (p = .007), a history of infectious mononucleosis (p = .002), and irritable bowel syndrome (p = .005) were associated with more frequent CCSVI diagnosis. Current or previous smoking (p = .029) showed a trend for association with more frequent CCSVI diagnosis, while use of dietary supplements (p = .018) showed a trend for association with less frequent CCSVI diagnosis.

Conclusions

Risk factors for CCSVI differ from established risk factors for peripheral venous diseases. Vascular, infectious and inflammatory factors were associated with higher CCSVI frequency.  相似文献   
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