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421.
Ana Sílvia Franco Pinheiro Moreira José Pires de Lemos Filho Gerhard Zotz Rosy Mary dos Santos Isaias 《Flora》2009,204(8):604-611
This study compares photosynthetic and structural features of Dichaea cogniauxiana and Epidendrum secundum leaves and roots. The diurnal titratable acidity fluctuations indicated crassulacean acid metabolism (CAM) in E. secundum leaves, associated with anatomical features like thick cuticle, large and vacuolated cells, and reduced stomata size and frequency. Roots of both species had chloroplasts in their cortical parenchyma. However, neither the roots nor D. cogniauxiana leaves did show tissue sap acidity fluctuations. This indicates C3 metabolism in these organs. This lack of oscillation of organic acids in Epidendrum roots was at odds with a CAM-like 13C ratio, suggesting that in spite of active CO2 fixation in roots during the day, the bulk of carbon is imported from the leaves. Roots of both species showed Fv/Fm, ΔF/Fm′, ETR values similar to reports from other non-foliar photosynthetic organs. Besides reducing root carbon cost, root photosynthesis may also be important by alleviating potential hypoxia, since water-saturated velamen severely impedes the gas exchange between radicular cortex. 相似文献
422.
423.
Alain?GorielyEmail author Marc?G.?D.?Geers Gerhard?A.?Holzapfel Jayaratnam?Jayamohan Antoine?Jérusalem Sivabal?Sivaloganathan Waney?Squier Johannes?A.?W.?van?Dommelen Sarah?Waters Ellen?Kuhl 《Biomechanics and modeling in mechanobiology》2015,14(5):931-965
The human brain is the continuous subject of extensive investigation aimed at understanding its behavior and function. Despite a clear evidence that mechanical factors play an important role in regulating brain activity, current research efforts focus mainly on the biochemical or electrophysiological activity of the brain. Here, we show that classical mechanical concepts including deformations, stretch, strain, strain rate, pressure, and stress play a crucial role in modulating both brain form and brain function. This opinion piece synthesizes expertise in applied mathematics, solid and fluid mechanics, biomechanics, experimentation, material sciences, neuropathology, and neurosurgery to address today’s open questions at the forefront of neuromechanics. We critically review the current literature and discuss challenges related to neurodevelopment, cerebral edema, lissencephaly, polymicrogyria, hydrocephaly, craniectomy, spinal cord injury, tumor growth, traumatic brain injury, and shaken baby syndrome. The multi-disciplinary analysis of these various phenomena and pathologies presents new opportunities and suggests that mechanical modeling is a central tool to bridge the scales by synthesizing information from the molecular via the cellular and tissue all the way to the organ level. 相似文献
424.
Extraction and long‐term storage of S‐layer proteins and flagella from Lysinibacillus sphaericus NCTC 9602: Building blocks for nanotechnology
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Anja Blüher Kai Ostermann Petra Jäckel Andrè Clemens Beate Katzschner Gerhard Rödel Michael Mertig 《Engineering in Life Science》2015,15(4):410-415
Self‐assembling surface layer (SL) proteins of bacteria have been widely studied, in particular their use as molecularly defined, 2D coatings of technical surfaces. An important prerequisite is the availability of a sufficient amount of protein. However, a detailed and optimized protocol for the complete SL extraction is so far not available. Here, we describe the complete purification and reassembly procedure of an SL protein of Lysinibacillus sphaericus NCTC 9602, starting from the cultivation of cells, the preparation and purification of SL proteins up to the long‐term storage and in vitro self‐assembly of the proteins. All crucial steps of the procedure are assessed by different microscopic techniques, such as light microscopy, atomic force microscopy, and scanning electron microscopy as well as by SDS‐PAGE as a biochemical method. We demonstrate that storage of the protein in the presence of sodium azide or upon lyophilization allows the preservation of the self‐assembly properties for at least 9 years. Additionally, we describe a method allowing the extraction of intact flagella with lengths in the range up to 4 μm. Flagella may have applications in bio‐nanotechnology, for example as templates for metallic nanowires. 相似文献
425.
Félix Ambrosio-Gallardo Carlos Cruz-Fuentes Gerhard Heinze-Martin Jorge Caraveo-Anduaga José Cortés-Sotres 《PloS one》2015,10(1)
Introduction
Minor physical anomalies (MPA) are dysmorphic features that reflect deviations in early development, are morphological variants that appear during the first trimester of pregnancy and could be used as a marker of disease risk in susceptible people. The literature agrees that the number of MPA is higher in patients with schizophrenia compared with their relatives and healthy subjects. The purpose of this study is to compare the MPA, assessed using the Gourion Scale, in complete nuclear families (families with a member with schizophrenia and control families) by determining the MPA mean, concordance and heritability for the total score on the MPA Gourion Scale for each anomaly.Method
The sample consisted of 60 families with at least one schizophrenic patient (284 members) and 61 control families (249 members). Results: The mean total score for the scale was 5.72 ± 2.3 MPA in the case of families with at least one schizophrenic patient and 1.8 ± 4.46 MPA for control families. The average for families of patients without considering the patient in the analysis was 5.59 ± 2.3 MPA; for patients, the mean was 6.14 ± 2.4 MPA. In the analysis by anomaly differences were found only in eleven anomalies found no evidence of heritability or concordance.Conclusions
MPA occur more frequently in patients, but a pattern of low consistency between them persists. It is concluded that MPA could be a marker of neurodevelopmental problems, but it is not suitable to consider them a Gourion scale as endophenotype. 相似文献426.
DNA barcoding largely supports 250 years of classical taxonomy: identifications for Central European bees (Hymenoptera,Apoidea partim)
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Stefan Schmidt Christian Schmid‐Egger Jérôme Morinière Gerhard Haszprunar Paul D. N. Hebert 《Molecular ecology resources》2015,15(4):985-1000
This study presents DNA barcode records for 4118 specimens representing 561 species of bees belonging to the six families of Apoidea (Andrenidae, Apidae, Colletidae, Halictidae, Megachilidae and Melittidae) found in Central Europe. These records provide fully compliant barcode sequences for 503 of the 571 bee species in the German fauna and partial sequences for 43 more. The barcode results are largely congruent with traditional taxonomy as only five closely allied pairs of species could not be discriminated by barcodes. As well, 90% of the species possessed sufficiently deep sequence divergence to be assigned to a different Barcode Index Number (BIN). In fact, 56 species (11%) were assigned to two or more BINs reflecting the high levels of intraspecific divergence among their component specimens. Fifty other species (9.7%) shared the same Barcode Index Number with one or more species, but most of these species belonged to a distinct barcode cluster within a particular BIN. The barcode data contributed to clarifying the status of nearly half the examined taxonomically problematic species of bees in the German fauna. Based on these results, the role of DNA barcoding as a tool for current and future taxonomic work is discussed. 相似文献
427.
Samir El Alaoui Brjánn Ljótsson Erik Hedman Viktor Kaldo Evelyn Andersson Christian Rück Gerhard Andersson Nils Lindefors 《PloS one》2015,10(4)
Objective
A central goal of health care is to improve patient outcomes. Although several studies have demonstrated the effectiveness of therapist guided internet-based cognitive behaviour therapy (ICBT) for social anxiety disorder (SAD), a significant proportion of patients do not respond to treatment. Consequently, the aim of this study was to identify individual characteristics and treatment program related factors that could help clinicians predict treatment outcomes and adherence for individuals with SAD.Method
The sample comprised longitudinal data collected during a 4-year period of adult individuals (N = 764) treated for SAD at a public service psychiatric clinic. Weekly self-rated Liebowitz Social Anxiety Scale (LSAS-SR) scores were provided. Rates of symptomatic change during treatment and adherence levels were analysed using multilevel modelling. The following domains of prognostic variables were examined: (a) socio-demographic variables; (b) clinical characteristics; (c) family history of mental illness; and (d) treatment-related factors.Results
Higher treatment credibility and adherence predicted a faster rate of improvement during treatment, whereas higher overall functioning level evidenced a slower rate of improvement. Treatment credibility was the strongest predictor of greater adherence. Having a family history of SAD-like symptoms was also associated with greater adherence, whereas Attention-Deficit/Hyperactivity Disorder (ADHD)-like symptoms, male gender, and family history of minor depression predicted lower adherence. Also, the amount of therapist time spent per treatment module was negatively associated with adherence.Conclusions
Results from a large clinical sample indicate that the credibility of ICBT is the strongest prognostic factor explaining individual differences in both adherence level and symptomatic improvement. Early screening of ADHD-like symptoms may help clinicians identify patients who might need extra support or an adjusted treatment. Therapist behaviours that promote adherence may be important for treatment response, although more research is needed in order to determine what type of support would be most beneficial. 相似文献428.
Johannes Salamon László Papp Zoltán Tóth Azien Laqmani Ivayla Apostolova Gerhard Adam Victor F. Mautner Thorsten Derlin 《PloS one》2015,10(12)
Purpose
To determine the metabolically active whole-body tumor volume (WB-MTV) on F-18-fluorodeoxyglucose positron emission tomography/computed tomography (F-18-FDG PET/CT) in individuals with neurofibromatosis type 1 (NF1) using a three-dimensional (3D) segmentation and computerized volumetry technique, and to compare PET WB-MTV between patients with benign and malignant peripheral nerve sheath tumors (PNSTs).Patients and Methods
Thirty-six NF1 patients (18 patients with malignant PNSTs and 18 age- and sex-matched controls with benign PNSTs) were examined by F-18-FDG PET/CT. WB-MTV, whole-body total lesion glycolysis (WB-TLG) and a set of semi-quantitative imaging-based parameters were analyzed both on a per-patient and a per-lesion basis.Results
On a per-lesion basis, malignant PNSTs demonstrated both a significantly higher MTV and TLG than benign PNSTs (p < 0.0001). On a per-patient basis, WB-MTV and WB-TLG were significantly higher in patients with malignant PNSTs compared to patients with benign PNSTs (p < 0.001). ROC analysis showed that MTV and TLG could be used to differentiate between benign and malignant tumors.Conclusions
WB-MTV and WB-TLG may identify malignant change and may have the potential to provide a basis for investigating molecular biomarkers that correlate with metabolically active disease manifestations. Further evaluation will determine the potential clinical impact of these PET-based parameters in NF1. 相似文献429.
Nicolas Bertholet John A. Cunningham Mohamed Faouzi Jacques Gaume Gerhard Gmel Bernard Burnand Jean-Bernard Daeppen 《PloS one》2015,10(12)
Introduction
Alcohol use is one of the leading modifiable morbidity and mortality risk factors among young adults.Study Design
2 parallel-group randomized controlled trial with follow-up at 1 and 6 months.Setting/Participants
Internet based study in a general population sample of young men with low-risk drinking, recruited between June 2012 and February 2013.Intervention: Internet-based brief alcohol primary prevention intervention (IBI). The IBI aims at preventing an increase in alcohol use: it consists of normative feedback, feedback on consequences, calorific value alcohol, computed blood alcohol concentration, indication that the reported alcohol use is associated with no or limited risks for health. Intervention group participants received the IBI. Control group (CG) participants completed only an assessment.Main Outcome Measures
Alcohol use (number of drinks per week), binge drinking prevalence. Analyses were conducted in 2014–2015.Results
Of 4365 men invited to participate, 1633 did so; 896 reported low-risk drinking and were randomized (IBI: n = 451; CG: n = 445). At baseline, 1 and 6 months, the mean (SD) number of drinks/week was 2.4(2.2), 2.3(2.6), 2.5(3.0) for IBI, and 2.4(2.3), 2.8(3.7), 2.7(3.9) for CG. Binge drinking, absent at baseline, was reported by 14.4% (IBI) and 19.0% (CG) at 1 month and by 13.3% (IBI) and 13.0% (CG) at 6 months. At 1 month, beneficial intervention effects were observed on the number of drinks/week (p = 0.05). No significant differences were observed at 6 months.Conclusion
We found protective short term effects of a primary prevention IBI.Trial Registration
Controlled-Trials.com ISRCTN55991918 相似文献430.
Bernhard Schwaberger Gerhard Pichler Alexander Avian Corinna Binder-Heschl Nariae Baik Berndt Urlesberger 《PloS one》2015,10(9)