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991.
Fabio Badalamenti Giuseppe Di Carlo Giovanni D’Anna Michele Gristina Marco Toccaceli 《Hydrobiologia》2006,555(1):253-261
Between 1981 and 1993 a methane pipeline was deployed between Sicily (Italy) and Tunisia. This involved the construction of
a pipeline trench, which damaged the Posidonia oceanica (L.) Delile meadow at Capo Feto (SW Sicily, Italy) and disturbed the surrounding meadow. Seagrass growth and population dynamics
were examined at different depth ranges and at increasing distances from the construction site outer limit (5, 15, 30, 50 m).
Results showed significant differences between the shallow (10±3.3 m) and the deep (20±4.6 m) meadow as well as differences
among distances. The age structure of P. oceanica varied along the distance gradient and with depth. The mortality rate decreased with distance from the trench at all depth
ranges, showing that the plants close to the excavation suffered a higher level of disturbance. Turnover and annual gross
shoot recruitment rate (Rgross) were higher in the shallow portion of the meadow than in the deep range. Forecast of future meadow development (Rnet) close to the trench indicates that, if present conditions are maintained, shoot density will be reduced by 50% over the
next 6 to 17 yrs. 相似文献
992.
Luisa Valentini Alina Iulia Iorga Teresa De Santis Barbara Ambruosi Karine Reynaud Sylvie Chastant-Maillard Antonio Ciro Guaricci Michele Caira Maria Elena Dell’Aquila 《Animal reproduction science》2010,117(1-2):166-177
This study investigates the mitochondrial (mt) distribution in canine ovarian oocytes examined at recovery time, as related to the reproductive cycle stage, and in oviductal oocytes. Ovarian Germinal Vesicle (GV) stage oocytes were recovered from bitches in anestrous (A, n = 2), follicular phase (F, n = 4), ovulation (O, n = 2), early luteal (EL, n = 7) and mid/late luteal phase (MLL, n = 2). Oviductal GV, metaphase I (MI) or MII stage oocytes were recovered from six bitches between 56 and 110 h after ovulation. Mitochondria were revealed by using MitoTracker Orange CMTM Ros and confocal microscopy. In ovarian oocytes, three mt distribution patterns were found: (I) small aggregates diffused throughout the cytoplasm; (II) diffused tubular networks; (III) pericortical tubular networks. Significantly higher rates of oocytes showing heterogeneous mt patterns (II + III) were obtained from bitches in F (75%) and in O (96%) compared with bitches in A (31%; F vs. A: P < 0.05; O vs. A: P < 0.001), in EL (61%; O vs. EL: P < 0.01), or in MLL (0%; F vs. MLL: P < 0.05; O vs. MLL: P < 0.001). Fluorescence intensity did not vary according to mt distribution pattern except that it was lower in oocytes recovered in EL phase and showing small mt aggregations (P < 0.001). The majority of ovulated MII stage oocytes (79%) showed diffused tubular mt network. We conclude that mt distribution pattern of canine ovarian immature oocytes changes in relation to reproductive cycle stage and that patterns observed in oocytes recovered from bitches in periovulatory phases are heterogeneous and similar to those of in vivo matured oocytes. 相似文献
993.
994.
The Jalview Java alignment editor 总被引:26,自引:0,他引:26
Multiple sequence alignment remains a crucial method for understanding the function of groups of related nucleic acid and protein sequences. However, it is known that automatic multiple sequence alignments can often be improved by manual editing. Therefore, tools are needed to view and edit multiple sequence alignments. Due to growth in the sequence databases, multiple sequence alignments can often be large and difficult to view efficiently. The Jalview Java alignment editor is presented here, which enables fast viewing and editing of large multiple sequence alignments. 相似文献
995.
Ricardo Krause Martinez De Souza Meire Silva Batistela Paulo Sergio Faro Santos Michele Christine Landemberger Ricardo Ramina 《朊病毒》2017,11(6):465-468
Here, we report the first case of V180I rare mutation in a Brazilian woman whose clinical condition started with memory impairment for recent events and insomnia with 2 months of evolution, without any other alterations in neurological examination. Both the electroencephalogram (EEG) and the routine biochemical examination of cerebrospinal fluid (CSF) were normal. CSF 14-3-3 protein search was positive. Magnetic resonance imaging (MRI) of the encephalon showed findings suggestive of Creutzfeldt-Jakob disease, confirmed by sequencing of PRNP gene that reveal V180I mutation also homozygosity for methionine at codon 129 (M129M). 相似文献
996.
Antonella Mastrorocco Nicola Antonio Martino Giuseppina Marzano Giovanni Michele Lacalandra Elena Ciani Bernard A. J. Roelen Maria Elena Dell'Aquila Fiorenza Minervini 《Molecular reproduction and development》2019,86(10):1430-1443
Beauvericin (BEA) is a mycotoxin produced by Beauveria bassiana and Fusarium species recently reported as toxic on porcine oocyte maturation and embryo development. The aim of this study was to assess, in the juvenile sheep, whether its effects are due to alterations of oocyte and/or embryo bioenergetic/oxidative status. Cumulus‐oocyte‐complexes (COCs) were exposed to BEA during in vitro maturation (IVM), evaluated for cumulus cell (CC) apoptosis, oocyte maturation and bioenergetic/oxidative status or subjected to in vitro fertilization (IVF) and embryo culture (IVEC). Oocyte nuclear maturation and embryo development were assessed after Hoechst staining and CC apoptosis was analysed by terminal deoxynucleotidyl transferase‐mediated dUTP nick‐End labeling assay and chromatin morphology after Hoechst staining by epifluorescence microscopy. Oocyte and blastocyst bioenergetic/oxidative status were assessed by confocal microscopy after mitochondria and reactive oxygen species labelling with specific probes. BEA showed various toxic effects, that is, short‐term effects on somatic and germinal compartment of the COC (CCs and the oocyte) and long‐term carry‐over effects on developing embryos. In detail, at 5 µM, it significantly reduced oocyte maturation and immature oocytes showed increased late‐stage (Type C) CC apoptosis and DNA fragmentation while matured oocytes showed unaffected CC viability but abnormal mitochondrial distribution patterns. At lower tested concentrations (3–0.5 µM), BEA did not affect oocyte maturation, but matured oocytes showed reduced mitochondrial activity. At low concentrations, BEA impaired embryo developmental capacity and blastocyst quality after IVF and IVEC. In conclusion, in the juvenile sheep, COC exposure to BEA induces CC apoptosis and oocyte mitochondrial dysfunction with negative impact on embryo development. 相似文献
997.
Paola Nicolini Michele M. Ciulla Gabriella Malfatto Carlo Abbate Daniela Mari Paolo D. Rossi Emanuela Pettenuzzo Fabio Magrini Dario Consonni Federico Lombardi 《PloS one》2014,9(5)
Background
Mild cognitive impairment (MCI) is set to become a major health problem with the exponential ageing of the world''s population. The association between MCI and autonomic dysfunction, supported by indirect evidence and rich with clinical implications in terms of progression to dementia and increased risk of mortality and falls, has never been specifically demonstrated.Aim
To conduct a comprehensive assessment of autonomic function in subjects with MCI by means of power spectral analysis (PSA) of heart rate variability (HRV) at rest and during provocative manoeuvres.Methods
This cross-sectional study involved 80 older outpatients (aged ≥65) consecutively referred to a geriatric unit and diagnosed with MCI or normal cognition (controls) based on neuropsychological testing. PSA was performed on 5-minute electrocardiographic recordings under three conditions—supine rest with free breathing (baseline), supine rest with paced breathing at 12 breaths/minute (parasympathetic stimulation), and active standing (orthosympathetic stimulation)—with particular focus on the changes from baseline to stimulation of indices of sympathovagal balance: normalized low frequency (LFn) and high frequency (HFn) powers and the LF/HF ratio. Blood pressure (BP) was measured at baseline and during standing. Given its exploratory nature in a clinical population the study included subjects on medications with a potential to affect HRV.Results
There were no significant differences in HRV indices between the two groups at baseline. MCI subjects exhibited smaller physiological changes in all three HRV indices during active standing, consistently with a dysfunction of the orthosympathetic system. Systolic BP after 10 minutes of standing was lower in MCI subjects, suggesting dysautonomia-related orthostatic BP dysregulation.Conclusions
Our study is novel in providing evidence of autonomic dysfunction in MCI. This is associated with orthostatic BP dysregulation and the ongoing follow-up of the study population will determine its prognostic relevance as a predictor of adverse health outcomes. 相似文献998.
Plant hydraulics as a central hub integrating plant and ecosystem function: meeting report for ‘Emerging Frontiers in Plant Hydraulics’ (Washington,DC, May 2015) 下载免费PDF全文
Lawren Sack Marilyn C. Ball Craig Brodersen Stephen D. Davis David L. Des Marais Lisa A. Donovan Thomas J. Givnish Uwe G. Hacke Travis Huxman Steven Jansen Anna L. Jacobsen Daniel M. Johnson George W. Koch Christophe Maurel Katherine A. McCulloh Nate G. McDowell Andrew McElrone Frederick C. Meinzer Peter J. Melcher Gretchen North Matteo Pellegrini William T. Pockman R. Brandon Pratt Anna Sala Louis S. Santiago Jessica A. Savage Christine Scoffoni Sanna Sevanto John Sperry Stephen D. Tyerman Danielle Way N. Michele Holbrook 《Plant, cell & environment》2016,39(9):2085-2094
Water plays a central role in plant biology and the efficiency of water transport throughout the plant affects both photosynthetic rate and growth, an influence that scales up deterministically to the productivity of terrestrial ecosystems. Moreover, hydraulic traits mediate the ways in which plants interact with their abiotic and biotic environment. At landscape to global scale, plant hydraulic traits are important in describing the function of ecological communities and ecosystems. Plant hydraulics is increasingly recognized as a central hub within a network by which plant biology is connected to palaeobiology, agronomy, climatology, forestry, community and ecosystem ecology and earth‐system science. Such grand challenges as anticipating and mitigating the impacts of climate change, and improving the security and sustainability of our food supply rely on our fundamental knowledge of how water behaves in the cells, tissues, organs, bodies and diverse communities of plants. A workshop, ‘Emerging Frontiers in Plant Hydraulics’ supported by the National Science Foundation, was held in Washington DC, 2015 to promote open discussion of new ideas, controversies regarding measurements and analyses, and especially, the potential for expansion of up‐scaled and down‐scaled inter‐disciplinary research, and the strengthening of connections between plant hydraulic research, allied fields and global modelling efforts. 相似文献
999.
Yongping Gao Christopher M. Gillen Michele G. Wheatly 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2009,152(3):216-225
Calmodulin (CaM) is a highly conserved calcium (Ca2+) binding protein that transduces Ca2+ signals into downstream effects influencing a range of cellular processes, including Ca2+ homeostasis. The present study explores CaM expression when Ca2+ homeostasis is challenged during the mineralization cycle of the freshwater crayfish (Procambarus clarkii). In this paper we report the cloning of a CaM gene from axial abdominal crayfish muscle (referred to as pcCaM). The pcCaM mRNA is ubiquitously expressed but is far more abundant in excitable tissue (muscle, nerve) than in any epithelia (gill, antennal gland, digestive) suggesting that it plays a greater role in the biology of excitation than in epithelial ion transport. In muscle cells the pcCaM was colocalized on the plasma membrane with the Ca2+ ATPase (PMCA) known to regulate intracellular Ca2+ through basolateral efflux. While PMCA exhibits a greater upregulation in epithelia (than in non-epithelial tissues) during molting stages requiring transcellular Ca2+ flux (pre- and postmolt compared with intermolt), expression of pcCaM exhibited a uniform increase in epithelial and non-epithelial tissues alike. The common increase in expression of CaM in all tissues during pre- and postmolt stages (compared with intermolt) suggests that the upregulation is systemically (hormonally) mediated. Colocalization of CaM with PMCA confirms physiological findings that their regulation is linked. 相似文献
1000.
Pier L. Biagi Alessandra Bordoni Silvana Hrelia Michele Celadon Edoardo Turchetto 《The Journal of nutritional biochemistry》1993,4(12):690-694
Polyenylphosphatidylcholine is a choline-glycerophospholipid containing up to 80% of total fatty acids as linoleic acid and may be an important factor in ensuring normal functioning of cell membranes. We tested the effect of a polyenylphosphatidylcholine-supplemented diet and compared it with both a trilinolein-supplemented and a laboratory chow diet on the fatty acid composition, microviscosity, and delta-6-desaturase activity of liver microsomal membranes of 12-month-old rats, in the absence or presence of oxidative stress induced by adriamycin. Polyenylphosphatidylcholine- and trilinolein-supplemented diets showed a similar increase in linoleic acid content and delta-6-desaturase activity in liver microsomes, indicating that low amounts of linoleic acid are able to partially restore the enzyme activity in old rats, independent of the source of linoleic acid. After adriamycin treatment, delta-6-desaturase activity increased in polyenylphosphatidylcholine and trilinolein groups, indicating a protective mechanism against the damage induced by polyunsaturated fatty acid peroxidation. The measurement of malondialdehyde production showed a protective effect on adriamycin-induced lipid peroxidation by polyenylphosphatidylcholine supplementation only. Microsomal membrane microviscosity did not change independent of diet and adriamycin treatment, suggesting that the response of microsomes to lipid peroxidation might be the maintenance of a given membrane order. Administration of polyenylphosphatidylcholine can prevent or minimize the liver damage induced by adriamycin treatment. 相似文献