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1.
A Potamogeton hybrid recently discovered in Finland was proven to be a new taxon, which has a different parentage than the most similar P.×vepsicus (=P. natans×praelongus) described from Russia. Based on molecular and morphological investigation, the new hybrid was identified as P. alpinus×natans and is here described as P.×exilis nothosp. nov. The hybrid is known only from several nearby localities in a single river system. All discovered colonies almost certainly originate from a single hybridization event that occurred in the upper part of the river system. Other localities downstream have been established through fragmentation and dispersal of stems and rhizomes of this sterile hybrid. A detailed morphological comparison of the new hybrid with similar hybrids and species is provided. 相似文献
2.
Pálenícek T Hlinák Z Bubeníková-Valesová V Votava M Horácek J 《Neuro endocrinology letters》2007,28(6):781-788
3,4-methylenedioxymethamphetamine (MDMA, ecstasy) is a widely abused drug that impairs behavioral, emotional and cognitive functions in humans and animals. The aim of this study was to evaluate MDMA effects on the spontaneous behavioral repertoire of rats with a focus on the gender differences. MDMA was given subcutaneously in a single dose of 2.5, 5 and 10 mg/kg and the spontaneous behavior of male and female rats was studied using the open field test. Behavioral patterns (locomotion, rearing, floor-sniffing, air-sniffing, grooming, immobility and stereotypy) were registered in two sessions - 30 and 60 min following MDMA administration; each session lasting 5 min. We found that MDMA totally disrupted the structure and timing of spontaneous behavioral patterns in both genders; no evident differences were measured between either of the sessions. MDMA irrespective of the dosage produced hyperlocomotion, excessive floor-sniffing and almost absolute suppression of grooming and immobility. A biphasic effect of MDMA was found in rearing. Gender differences were present namely in rearing and sniffing stereotypy. This study also confirms that behavioral experiments should focus on more behavioral elements than only on e.g. locomotion and that the observer-based approach still gives the most reliable results. 相似文献
3.
Mammalian Genome - Aneuploidy (abnormal chromosome number) accompanies reduced ovarian function in humans and mice, but the reasons behind this concomitance remain underexplored. Some variants in... 相似文献
4.
Sarkar S Floto RA Berger Z Imarisio S Cordenier A Pasco M Cook LJ Rubinsztein DC 《The Journal of cell biology》2005,170(7):1101-1111
Macroautophagy is a key pathway for the clearance of aggregate-prone cytosolic proteins. Currently, the only suitable pharmacologic strategy for up-regulating autophagy in mammalian cells is to use rapamycin, which inhibits the mammalian target of rapamycin (mTOR), a negative regulator of autophagy. Here we describe a novel mTOR-independent pathway that regulates autophagy. We show that lithium induces autophagy, and thereby, enhances the clearance of autophagy substrates, like mutant huntingtin and alpha-synucleins. This effect is not mediated by glycogen synthase kinase 3beta inhibition. The autophagy-enhancing properties of lithium were mediated by inhibition of inositol monophosphatase and led to free inositol depletion. This, in turn, decreased myo-inositol-1,4,5-triphosphate (IP3) levels. Our data suggest that the autophagy effect is mediated at the level of (or downstream of) lowered IP3, because it was abrogated by pharmacologic treatments that increased IP3. This novel pharmacologic strategy for autophagy induction is independent of mTOR, and may help treatment of neurodegenerative diseases, like Huntington's disease, where the toxic protein is an autophagy substrate. 相似文献
5.
Pavol Kois Zdenek Tocik Maria Spassova Wu-Yun Ren Ivan Rosenberg Jaume Farras Soler 《Nucleosides, nucleotides & nucleic acids》2013,32(10):1093-1109
Abstract In order to find the effects of unnatural nucleosides on the stability of duplex, several oligonucleotides containing 1-(2-deoxy-2-fluoro-β-D-arabinofuranosyl)-uracil(FAU),-cytosine (FAC) and -thymine (FMAU) were synthesized by two alternative approaches: phosphoramidite method on an ABI 392 synthesizer and H-phosphonate procedure on our GeneSyn I universal module synthesizer. It was shown from the melting profiles that the presence of FMAU has a large stabilizing effect on the duplex. Replacement of thymidine with FAU, or deoxycytidine with FAC resulted in the formation of less stable duplexes. Temperature-dependent CD spectroscopy demonstrated that the structures of the fluorine containing oligomers are very similar to those of unmodified oligomers. 相似文献
6.
Dana Horakova Robert Zivadinov Bianca Weinstock-Guttman Eva Havrdova Jun Qu Miriam Tama?o-Blanco Darlene Badgett Michaela Tyblova Niels Bergsland Sara Hussein Laura Willis Jan Krasensky Manuela Vaneckova Zdenek Seidl Petra Lelkova Michael G. Dwyer Ming Zhang Haoying Yu Xiaotao Duan Tomas Kalincik Murali Ramanathan 《PloS one》2013,8(1)
Objectives
To investigate the associations of environmental MS risk factors with clinical and MRI measures of progression in high-risk clinically isolated syndromes (CIS) after the first demyelinating event.Methods
We analyzed 211 CIS patients (age: 28.9±7.8 years) enrolled in the SET study, a multi-center study of high-risk CIS patients. Pre-treatment samples were analyzed for IgG antibodies against cytomegalovirus (anti-CMV), Epstein Barr virus (EBV) early nuclear antigen-1 (EBNA-1), viral capsid antigen (VCA), early antigen-diffuse (EA-D), 25 hydroxy-vitamin D3 and cotinine levels and HLA DRB1*1501 status. The inclusion criteria required evaluation within 4 months of the initial demyelinating event, 2 or more brain MRI lesions and the presence of two or more oligoclonal bands in cerebrospinal fluid. All patients were treated with interferon-beta. Clinical and MRI assessments were obtained at baseline, 6, 12, and 24 months.Results
The time to first relapse decreased and the number of relapses increased with anti-CMV IgG positivity. Smoking was associated with increased number and volume of contrast-enhancing lesions (CEL) during the 2-year period. The cumulative number of CEL and T2 lesions during the 2-year period was greater for individuals in the highest quartile of anti-EBV VCA IgG antibodies. The percent loss of brain volume was increased for those in the highest quartile of with anti-EBV VCA IgG antibodies.Conclusions
Relapses in CIS patients were associated with CMV positivity whereas anti-EBV VCA positivity was associated with progression on MRI measures, including accumulation of CEL and T2 lesions and development of brain atrophy. 相似文献7.
Sebastian Fernandez-Pol Zdenek Slouka Souvik Bhattacharjee Yana Fedotova Stefan Freed Xiuli An Anthony A. Holder Estela Campanella Philip S. Low Narla Mohandas Kasturi Haldar 《Eukaryotic cell》2013,12(9):1179-1191
Eukaryotic parasites of the genus Plasmodium cause malaria by invading and developing within host erythrocytes. Here, we demonstrate that PfShelph2, a gene product of Plasmodium falciparum that belongs to the Shewanella-like phosphatase (Shelph) subfamily, selectively hydrolyzes phosphotyrosine, as shown for other previously studied Shelph family members. In the extracellular merozoite stage, PfShelph2 localizes to vesicles that appear to be distinct from those of rhoptry, dense granule, or microneme organelles. During invasion, PfShelph2 is released from these vesicles and exported to the host erythrocyte. In vitro, PfShelph2 shows tyrosine phosphatase activity against the host erythrocyte protein Band 3, which is the most abundant tyrosine-phosphorylated species of the erythrocyte. During P. falciparum invasion, Band 3 undergoes dynamic and rapid clearance from the invasion junction within 1 to 2 s of parasite attachment to the erythrocyte. Release of Pfshelph2 occurs after clearance of Band 3 from the parasite-host cell interface and when the parasite is nearly or completely enclosed in the nascent vacuole. We propose a model in which the phosphatase modifies Band 3 in time to restore its interaction with the cytoskeleton and thus reestablishes the erythrocyte cytoskeletal network at the end of the invasion process. 相似文献
8.
Vaccination of macaques with long-standing SIVmac251 infection lowers the viral set point after cessation of antiretroviral therapy 总被引:7,自引:0,他引:7
Tryniszewska E Nacsa J Lewis MG Silvera P Montefiori D Venzon D Hel Z Parks RW Moniuszko M Tartaglia J Smith KA Franchini G 《Journal of immunology (Baltimore, Md. : 1950)》2002,169(9):5347-5357
A cohort of rhesus macaques with long-standing SIVmac251 infection (> or =5 mo) was treated with continuous antiretroviral therapy (ART). A group of eight macaques was vaccinated with or without simultaneous administration of low dose IL-2 with the highly attenuated poxvirus vector (NYVAC) vaccine candidate expressing the SIVmac structural gag-pol-env (gpe) genes and a novel chimeric fusion protein derived from the rev-tat-nef (rtn) regulatory genes. Control groups consisted of mock-vaccinated macaques or animals treated only with IL-2. Vaccination significantly expanded both virus-specific CD4(+) and CD8(+) T cell responses, and IL-2 further increased the vaccine-induced response to an immunodominant Gag epitope. Following antiretroviral treatment interruption, the viral set point was significantly lower in vaccinated than in control macaques for at least 4 consecutive mo, and viral containment was inversely correlated with vaccine-induced, virus-specific CD4(+) and CD8(+) T cell responses. These data provide the proof of concept that therapeutic vaccination before cessation of ART may be a feasible approach in the clinical management of HIV-1 infection. 相似文献
9.
During a random survey of entomopathogenic nematodes in the provinces of Sichuan and Gansu (eastern Tibet) in 2004, soil samples from several sites were collected and tested for the incidence of entomopathogenic nematodes. A new species was collected in this survey and it is described herein as Steinernema cholashanense n. sp. Steinernema cholashanense n. sp. is characterized by morphology and morphometry of the IJ and male. For the IJ, the new species can be recognized by the average body length 843 microm, esophagus length 125 microm, H%=39% and E%=81%. The lateral field pattern is 2, 5, 7, 4, 2. The male of the first generation is characterized by spicule shape and length and especially with prominent velum and the presence of a mucron on both generations. The average body length of the IJ of S. cholashanense n. sp. (843 microm) is shorter than that of S. oregonense (980 microm), S. kraussei (951 microm) and S. litorale (909 microm), similar to that of S. feltiae (849 microm), but longer than that of S. weiseri (740 microm), S. jollietti (711 microm) and S. hebeiense (658 microm). Esophagus length of the new species (125 microm) is closer to that of S. jollieti (123 microm) but longer than that of S. weiseri (113 microm) and shorter than that of S. oregonense (132 microm), S. kraussei (134 microm) and S. feltiae (136 microm). E% of the new species (81) is similar to that of S. kraussei (80), but smaller than that of S. jollieti (88), S. weiseri (95), S. oregonense (100) and S. feltiae (119). Spicule head length of the new species is almost the same as its width, this character is similar to that of S. kraussei but it is different from this species by its prominent velum. The new species can be recognized further by characteristics of sequences of ITS and D2D3 regions and cross hybridization with closely related species, S. feltiae, S. kraussei and S. oregonense. 相似文献
10.
Hubálek Z 《Journal of wildlife diseases》2004,40(4):639-659
The potential for transport and dissemination of certain pathogenic microorganisms by migratory birds is of concern. Migratory birds might be involved in dispersal of microorganisms as their biological carriers, mechanical carriers, or as carriers of infected hematophagous ecto-parasites (e.g., ixodid ticks). Many species of microorganisms pathogenic to homeothermic vertebrates including humans have been associated with free-living migratory birds. Migratory birds of diverse species can play significant roles in the ecology and circulation of some arboviruses (e.g., eastern and western equine encephalomyelitis and Sindbis alphaviruses, West Nile and St. Louis encephalitis flaviviruses), influenza A virus, Newcastle disease virus, duck plague herpes-virus, Chlamydophila psittaci, Anaplasma phagocytophilum, Borrelia burgdorferi sensu lato, Campylobacter jejuni, Salmonella enterica, Pasteurella multocida, Mycobacterium avium, Candida spp., and avian hematozoans. The efficiency of dispersal of pathogenic microorganisms depends on a wide variety of biotic and abiotic factors affecting the survival of the agent in, or disappearance from, a habitat or ecosystem in a new geographic area. 相似文献