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991.
Anna Vidus-Rosin Alberto Meriggi Elisa Cardarelli Sara Serrano-Perez Maria-Chiara Mariani Chiara Corradelli Annalisa Barba 《Acta theriologica》2011,56(1):53-61
In northern Italy, the range of the Eastern cottontail (Sylvilagus floridanus) largely overlaps with that of the native European hare (Lepus europaeus) on the Po Plain. Both species appear to have similar habitat requirements. We studied habitat selection by hares and cottontails
during feeding activity from September 2006 to August 2007 in two areas where they occur alone (allopatry) and in one area
where they occur together (sympatry). The three areas were basically similar, so that shifts in habitat use observed in sympatry
should reflect the response to interspecific competition. Habitat selection was examined at micro- and macro-habitat levels
throughout seasons. Habitat breadth of both species followed the change of resource availability through seasons in allopatry
as well as in sympatry. No shifts in habitat use were evident at macro-habitat level, even during autumn which was the limiting
season. Exploitation of shared habitats by the two species seems to be promoted by differential micro-habitat use within macro-habitat
types. Cottontails used woods with dense understory in greater proportion than hares, and their present sites were concentrated
within the maximum distance of 20 m of the nearest shelter site. Hares were more likely than cottontails to exploit crops,
and their sites were distributed even greater than 80 m away from permanent cover patches. The habitat heterogeneity of agricultural
ecosystems within the sympatry range could buffer the negative effects of external factors (climate, human disturbance and
predation) on hares, and enhance the chances of exploitation of shared habitats by both species. 相似文献
992.
Venturi E Mio K Nishi M Ogura T Moriya T Pitt SJ Okuda K Kakizawa S Sitsapesan R Sato C Takeshima H 《Biochemistry》2011,50(13):2623-2632
Mitsugumin 23 (MG23) is a 23 kDa transmembrane protein localized to the sarcoplasmic/endoplasmic reticulum and nuclear membranes in a wide variety of cells. Although the characteristics imply the participation in a fundamental function in intracellular membrane systems, the physiological role of MG23 is unknown. Here we report the biochemical and biophysical characterization of MG23. Hydropathicity profile and limited proteolytic analysis proposed three transmembrane segments in the MG23 primary structure. Chemical cross-linking analysis suggested a homo-oligomeric assembly of MG23. Ultrastructural observations detected a large symmetrical particle as the predominant component and a small asymmetric assembly as the second major component in highly purified MG23 preparations. Single-particle three-dimensional reconstruction revealed that MG23 forms a large bowl-shaped complex equipped with a putative central pore, which is considered an assembly of the small asymmetric subunit. After reconstitution into planar phospholipid bilayers, purified MG23 behaved as a voltage-dependent, cation-conducting channel, permeable to both K(+) and Ca(2+). A feature of MG23 gating was that multiple channels always appeared to be gating together in the bilayer. Our observations suggest that the bowl-shaped MG23 can transiently assemble and disassemble. These building transitions may underlie the unusual channel gating behavior of MG23 and allow rapid cationic flux across intracellular membrane systems. 相似文献
993.
Cigarette smoking has long been tied to a multitude of poor health outcomes; however, in reproductive biology, smoking has shown several unintuitive findings. Smoking is associated with significantly decreased rates of endometriosis and endometrial cancer. Here, we show that treatment with cigarette smoke extract leads to increased mRNA and protein expression of homeobox A10 (HOXA10) and progesterone receptor (PGR) as well as more rapid decidualization of endometrial stromal cells in vitro. In vivo, mice exposed to cigarette smoke similarly showed increased expression of HOXA10 and PGR in the endometrium. Both HOXA10 and PGR drive endometrial differentiation and are suppressed in endometrial tumors and in endometriosis. The increased expression found upon exposure to cigarette smoke may provide a protective effect, mediating the decreased incidence of endometrial disease among smokers. This mechanism contrasts with the accepted paradigm that the effects of smoking on the uterus are secondary to ovarian alterations rather than direct effects on endometrium as demonstrated here. 相似文献
994.
Colombrita C Onesto E Tiloca C Ticozzi N Silani V Ratti A 《Archives italiennes de biologie》2011,149(1):83-99
Several RNA-processing genes have been implicated in the pathogenesis of Amyotrophic lateral sclerosis (ALS). In particular, causative mutations in the genes encoding for two DNA/RNA binding proteins, TAR DNA binding protein-43 (TDP-43) and fused in sarcoma/translocated in liposarcoma (FUS/TLS), were recently identified in ALS patients. These genetic findings and the presence of abnormal aggregates of these two RNA-binding proteins in ALS affected tissues suggest that molecular mechanisms regulating RNA metabolism are implicated in ALS pathogenesis through common pathways. In this review similarities and differences between TDP-43 and FUS/TLS proteins and their activities in physiological and pathological conditions will be discussed. 相似文献
995.
Ronchi D Bordoni A Cosi A Rizzuti M Fassone E Di Fonzo A Servida M Sciacco M Collotta M Ronzoni M Lucchini V Mattioli M Moggio M Bresolin N Corti S Comi GP 《Biochemical and biophysical research communications》2011,(2):245-248
Leigh syndrome (LS) is an incurable, nearly always fatal, neurodegenerative, pediatric disorder that results from respiratory chain failure. The most common mitochondrial DNA (mtDNA) mutations that result in LS are m.8993T→C/G and m.9176T→C/G, which were previously found in several patients with early-onset Leigh syndrome. Here, we describe clinical and molecular features of a novel pedigree, where LS developed in two siblings. The proband was a young woman with an unusual adult-onset LS. She harbored a homoplasmic m.9176T→C mutation, based on analysis of a muscle biopsy. In contrast, the brother died at a young age. This novel case report and literature review highlights the variability of phenotypic expression of the m.9176T→C mutation. 相似文献
996.
Campos E Moura TF Oliva A Leandro P Soveral G 《Biochemical and biophysical research communications》2011,(3):477-481
In general, erythrocytes are highly permeable to water, urea and glycerol. However, expression of aquaporin isoforms in erythrocytes appears to be species characteristic. In the present study, human (hRBC) and bovine (bRBC) erythrocytes were chosen for comparative studies due to their significant difference in membrane glycerol permeability.Osmotic water permeability (Pf) at 23 °C was (2.89 ± 0.37) × 10−2 and (5.12 ± 0.61) × 10−2 cm s−1 for human and bovine cells, respectively, with similar activation energies for water transport. Glycerol permeability (Pgly) for human ((1.37 ± 0.26) × 10−5 cm s−1) differed in three orders of magnitude from bovine erythrocytes ((5.82 ± 0.37) × 10−8 cm s−1) that also showed higher activation energy for glycerol transport. When compared to human, bovine erythrocytes showed a similar expression pattern of AQP1 glycosylated forms on immunoblot analysis, though in slight higher levels, which could be correlated with the 1.5-fold larger Pf found. However, AQP3 expression was not detectable. Immunofluorescence analysis confirmed the absence of AQP3 expression in bovine erythrocyte membranes.In conclusion, lack of AQP3 in bovine erythrocytes points to the lipid pathway as responsible for glycerol permeation and explains the low glycerol permeability and high Ea for transport observed in ruminants. 相似文献
997.
Flávio Lemes Fernandes Marcelo Coutinho Picanço Pablo Costa Gontijo Maria Elisa de Sena Fernandes Eliseu José Guedes Pereira Altair Arlindo Semeão 《Entomologia Experimentalis et Applicata》2011,139(2):120-127
The green scale, Coccus viridis (Green) (Hemiptera: Coccidae), is an insect pest of coffee and several other perennial cultivated plant species. We investigated changes in alkaloid and phenolic contents in coffee plants as a response to herbivory by this insect. Greenhouse‐grown, 11‐month‐old coffee plants were artificially infested with the coccid and compared with control, uninfested plants. Leaf samples were taken at 15, 30, 45, and 60 days after infestation, and high‐performance liquid chromatography was used to identify and quantify alkaloid and phenolic compounds induced by the coccids at each sampling date. Of the compounds investigated, caffeine was the main coffee alkaloid detected in fully developed leaves, and its concentration in infested plants was twice as high as in the control plants. The main coffee phenolics were caffeic and chlorogenic acid, and a significant increase in their concentrations occurred only in plants infested by C. viridis. A positive and significant relationship was found between alkaloid and phenolic concentrations and the infestation level by adults and nymphs of C. viridis. Caffeine and chlorogenic acid applied on coffee leaves stimulated the locomotory activity of the green scale, thus reducing their feeding compared to untreated leaves. This is the first study to show increased levels of coffee alkaloids and phenolics in response to herbivory by scale insects. The elevation of caffeine and chlorogenic acid levels in coffee leaves because of C. viridis infestation seems to affect this generalist insect by stimulating the locomotion of crawlers. 相似文献
998.
Elisa Mazzoni Ilaria Bononi Silvia Pietrobon Elena Torreggiani Marika Rossini Maura Pugliatti Ilaria Casetta Massimiliano Castellazzi Enrico Granieri Giovanni Guerra Fernanda Martini Mauro Tognon 《Journal of cellular physiology》2020,235(7-8):5847-5855
Published data support the hypothesis that viruses could be trigger agents of multiple sclerosis onset. This link is based on evidence of early exposure to viral agents in patients affected by this neurologic disease. JC (JC polyomavirus [JCPyV]), BK (BKPyV), and simian virus 40 (SV40) neurotropic polyomavirus footprints have been detected in brain tissue specimens and samples from patients affected by different neurological diseases. In this investigation, serum samples from patients affected by multiple sclerosis and other inflammatory and noninflammatory neurologic diseases, as well as healthy subjects representing the control, were investigated for immunoglobulin G (IgG) antibodies against JCPyV. To this end, an immunologic approach was employed, which consists of employing indirect enzyme-linked immunosorbent assay testing with synthetic peptides mimicking viral capsid protein 1 antigens. A significantly lower prevalence of IgG antibodies against JCPyV VP1 epitopes, with a low titer, was detected in serum samples from patients with multiple sclerosis (MS) and other neurologic diseases than in healthy subjects. Our study indicates that the prevalence of JCPyV antibodies from patients with multiple sclerosis is 50% lower than in healthy subjects, suggesting specific immune impairments. These results indicate that patients affected by neurological diseases, including MS, respond poorly to JCPyV VP1 antigens, suggesting specific immunologic dysfunctions. 相似文献
999.
Andrea Tagliapietra John Charles Rotondo Ilaria Bononi Elisa Mazzoni Federica Magagnoli Lucia Oton Gonzalez Carlo Contini Fortunato Vesce Mauro Tognon Fernanda Martini 《Journal of cellular physiology》2020,235(3):1888-1894
Droplet-digital polymerase chain reaction (ddPCR) technique was set up to detect/quantify Merkel cell polyomavirus (MCPyV) DNA in clinical specimens, including chorionic villi and peripheral blood mononuclear cells (PBMCs) from spontaneous abortion (SA)-affected females. This ddPCR assay showed high accuracy, sensitivity, and specificity in detecting MCPyV DNA cloned in a recombinant plasmid vector, the control. ddPCR was extended to MCPyV DNA to investigate/quantify its sequences in clinical samples. Overall, 400 samples were analyzed, that is, 100 chorionic villi and 100 PBMCs, from SA females (n = 100), the cases, and 100 chorionic villi and 100 PBMCs from females who underwent voluntary pregnancy interruption (VI, n = 100), the control. MCPyV DNA was detected in 4/100 (4%) and 5/100 (5%) of SA and VI chorionic villi, respectively. The mean viral DNA load was 1.99 ( ± 0.94 standard mean deviation [SD]) copy/104 cells in SA and 3.02 ( ± 1.86 [SD]) copy/104 cells in VI. In PBMCs, MCPyV DNA was revealed in 9/100 (9%) and 14/100 (14%) of SA and VI, with a mean of 2.09 ( ± 1.17 [SD]) copy/104 cells and 4.09 ( ± 4.26 [SD]) copy/104 cells in SA and VI, respectively. MCPyV gene expression analysis by quantitative PCR for the large T antigen (LT) and viral capsid protein 1 (VP1) showed their mRNAs in 2/4 (50%) SA- and 2/5 (40%) VI-MCPyV-positive samples. MCPyV DNA was detected/quantified using the ddPCR technique, in chorionic villi and PBMCs from SA and VI. In our experimental conditions, ddPCR provided a powerful tool to detect/quantify MCPyV DNA sequences in clinical samples. 相似文献
1000.