Vocalizations and courtship displays of the Bittern Botaurus stellaris

Capsule We report on the courtship behaviour of the Eurasian Bittern from direct observation in rice fields.     

Reception and learning of electric fields in bees

Honeybees, like other insects, accumulate electric charge in flight, and when their body parts are moved or rubbed together. We report that bees emit constant and modulated electric fields when flying, landing, walking and during the waggle dance. The electric fields emitted by dancing bees consist of low- and high-frequency components. Both components induce passive antennal movements in stationary bees according to Coulomb''s law. Bees learn both the constant and the modulated electric field components in the context of appetitive proboscis extension response conditioning. Using this paradigm, we identify mechanoreceptors in both joints of the antennae as sensors. Other mechanoreceptors on the bee body are potentially involved but are less sensitive. Using laser vibrometry, we show that the electrically charged flagellum is moved by constant and modulated electric fields and more strongly so if sound and electric fields interact. Recordings from axons of the Johnston organ document its sensitivity to electric field stimuli. Our analyses identify electric fields emanating from the surface charge of bees as stimuli for mechanoreceptors, and as biologically relevant stimuli, which may play a role in social communication.     

Seed germination requirements of Trembleya laniflora (Melastomataceae), an endemic species from neotropical montane rocky savannas

Trembleya laniflora is an endemic shrub from neotropical montane rocky savannas of southeastern Brazil. It has been indicated as a potential candidate for ecological restoration of abandoned iron‐ore mines due to heavy metal accumulation. Here, we evaluated the seed germination requirements of T. laniflora. Seeds collected in 2005 and 2008 were set to germinate under a broad range of temperature and light conditions. Seed viability was estimated by dissecting seeds under a dissecting microscope for embryo presence/absence. Seeds were photoblastic and optimum temperature range was 20–25°C, coinciding with the onset of the rainy season. Seeds were viable after 42 months of storage, which together with small seeds that easily get buried and light requirement for germination suggest formation of soil seed banks. Except the large fraction of embryoless seeds, almost all tested seeds germinated when incubated under light conditions; therefore, T. laniflora should be regarded to have nondormant seeds. Easiness of burial resulting from small seed size and positive photoblastism may both contribute to incorporation into soil seed banks. Our data suggest that the long‐term storage of T. laniflora seeds provides a useful strategy for plant reintroduction.     

Aberrant bispecific antibody pharmacokinetics linked to liver sinusoidal endothelium clearance mechanism in cynomolgus monkeys

Bispecific antibodies (BsAbs) can affect multiple disease pathways, thus these types of constructs potentially provide promising approaches to improve efficacy in complex disease indications. The specific and non-specific clearance mechanisms/biology that affect monoclonal antibody (mAb) pharmacokinetics are likely involved in the disposition of BsAbs. Despite these similarities, there are a paucity of studies on the in vivo biology that influences the biodistribution and pharmacokinetics of BsAbs. The present case study evaluated the in vivo disposition of 2 IgG-fusion BsAb formats deemed IgG-ECD (extracellular domain) and IgG-scFv (single-chain Fv) in cynomolgus monkeys. These BsAb molecules displayed inferior in vivo pharmacokinetic properties, including a rapid clearance (> 0.5 mL/hr/kg) and short half-life relative to their mAb counterparts. The current work evaluated factors in vivo that result in the aberrant clearance of these BsAb constructs. Results showed the rapid clearance of the BsAbs that was not attributable to target binding, reduced neonatal Fc receptor (FcRn) interactions or poor molecular/biochemical properties. Evaluation of the cellular distribution of the constructs suggested that the major clearance mechanism was linked to binding/association with liver sinusoidal endothelial cells (LSECs) versus liver macrophages. The role of LSECs in facilitating the clearance of the IgG-ECD and IgG-scFv BsAb constructs described in these studies was consistent with the minimal influence of clodronate-mediated macrophage depletion on the pharmacokinetics of the constructs in cynomolgus monkeys The findings in this report are an important demonstration that the elucidation of clearance mechanisms for some IgG-ECD and IgG-scFv BsAb molecules can be unique and complicated, and may require increased attention due to the proliferation of these more complex mAb-like structures.     

Firmicutes is an Important Component of Microbial Communities in Water-Injected and Pristine Oil Reservoirs,Western Siberia,Russia

The dominant microbial components of fluids from wells in pristine and water-injected, high-temperature, Western Siberian oil fields, were analyzed by PCR-DGGE. Particular emphasis was placed on sulphate-reducing organisms, due to their ecological and industrial importance. Bacterial phylotypes obtained from the non-water-injected Stolbovoye oil field were more diverse than those from the Samotlor field, which is subject to secondary oil recovery by reinjection of recycled production water. The majority of phylotypes from both sites were related to Firmicutes. The low similarity to their closest relatives indicates unique bacterial communities in deep underground production waters and crude oil. Archaeal phylotypes detected only in the Samotlor samples were represented by Methanosarcinales and Methanobacteriales.     

Overexpression of miR-26b-5p regulates the cell cycle by targeting CCND2 in GC-2 cells under exposure to extremely low frequency electromagnetic fields

The increasing prevalence of extremely low frequency electromagnetic fields (ELF-EMFs) exposure has raised considerable public concern regarding the potential hazardous effects of ELF-EMFs on male reproductive function. Increasing evidence indicates that miRNAs are necessary for spermatogenesis and male fertility. However, the regulation of miRNA expression and the roles of miRNAs in response to ELF-EMFs remain unclear. In our study, mouse spermatocyte-derived GC-2 cells were intermittently exposed to a 50 Hz ELF-EMF for 72 h (5 min on/10 min off) at magnetic field intensities of 1 mT, 2 mT and 3 mT. MiR-26b-5p was differentially expressed in response to different magnetic field intensities of ELF-EMFs. The host gene CTDSP1 showed an unmethylation status in GC-2 cells at different magnetic field intensities of ELF-EMF exposure. MiR-26b-5p had no significant, obvious influence on the cell viability, apoptosis or cell cycle of GC-2 cells. However, the overexpression of miR-26b-5p significantly decreased the percentage of G0/G1 phase cells and slightly increased the percentage of S phase cells compared to the sham group that was exposed to a 50 Hz ELF-EMF. Computational algorithms identified Cyclin D2 (CCND2) as a direct target of miR-26b-5p. MiR-26b-5p and a 50 Hz ELF-EMF altered the expression of CCND2 at both the mRNA and protein levels. Overexpressed miR-26b-5p in GC-2 cells can change the mRNA expression of CCND2 following 50 Hz ELF-EMF at 3 mT. These findings demonstrate that miR-26b-5p could serve as a potential biomarker following 50 Hz ELF-EMF exposure, and miR-26b-5p-CCND2-mediated cell cycle regulation might play a pivotal role in the biological effects of ELF-EMFs.     

Characterization of biofilm formation in natural water subjected to low-frequency electromagnetic fields

Electromagnetic field (EMF) treatment has proven to be effective against mineral scaling in water systems. Therefore, it should be assessed for the treatment of other deposits such as biofilms. In this study, a commercial device producing low-frequency EMF (1–10 kHz) was applied to a reactor fed with natural water for 45 days. The treatment promoted the concentration of microorganisms in suspension and limited the amount of sessile microorganisms in the biofilm, as determined by the measurement of total DNA, qPCR and microscopy. The structure of the bacterial community was assessed by t-RFLP and pyrosequencing analysis. The results showed that EMF treatment affected both planktonic and sessile community composition. EMFs were responsible for a shift in classes of Proteobacteria during development of the biofilm. It may be speculated that the EMF treatment affected particle solubility and/or microorganism hydration. This study indicated that EMFs modulated biofilm formation in natural water.     

外源性的电磁干预对神经病理性疼痛大鼠的镇痛效果研究

目的:探讨外源性的电磁干预方法对神经病理性疼痛大鼠的镇痛效果。方法:将30只成熟的雄性SD大鼠随机等分成3组:空白对照组(Control),坐骨神经慢性压迫损伤(CCI)组以及坐骨神经慢性压迫损伤协同电磁刺激组(CCI+EMF)。CCI组和CCI+EMF组的20只大鼠建立坐骨神经慢性压迫损伤模型,CCI+EMF组大鼠行外源性的全身性电磁刺激干预(脉冲波形,频率15 Hz,强度30 Gs),每天刺激6小时。在CCI模型构建的第0、3、6、9、12及15天对大鼠测试和比较足底机械痛阈值、足底热痛阈值、运动功能评分和神经传导速率。结果:CCI组大鼠的足底机械痛阈值、足底热痛阈值及感觉神经传导速率从CCI手术后的第3天即出现显著性降低,其6、9、12、15天足底机械痛阈值、足底热痛阈值及感觉神经传导速率均显著低于Control组(P0.01),而运动功能评分均显著高于Control组(P0.05)。CCI+EMF组大鼠的足底机械痛阈值、足底热痛阈值及感觉神经传导速率在第9、12、15天显著高于CCI组大鼠(P0.05),而运动功能评分均显著高于CCI l组。结论:外源性的电磁刺激对于神经病理性疼痛大鼠具有良好的镇痛效果,有望成为一种临床治疗神经病理性疼痛的新的物理治疗手段。