A method for two-dimensional characterization of animal vibrational signals transmitted along plant stems

Conventional approaches to measuring animal vibrational signals on plant stems use a single transducer to measure the amplitude of vibrations. Such an approach, however, will often underestimate the amplitude of bending waves traveling along the stem. This occurs because vibration transducers are maximally sensitive along a single axis, which may not correspond to the major axis of stem motion. Furthermore, stem motion may be more complex than that of a bending wave propagating along a single axis, and such motion cannot be described using a single transducer. Here, we describe a method for characterizing stem motion in two dimensions by processing the signals from two orthogonally positioned transducers. Viewed relative to a cross-sectional plane, a point on the stem surface moves in an ellipse at any one frequency, with the ellipse’s major axis corresponding to the maximum amplitude of vibration. The method outlined here measures the ellipse’s major and minor axes, and its angle of rotation relative to one of the transducers. We illustrate this method with measurements of stem motion during insect vibrational communication. It is likely the two-dimensional nature of stem motion is relevant to insect vibration perception, making this method a promising avenue for studies of plant-borne transmission. Electronic Supplementary Material The online version of this article () contains supplementary material, which is available to authorized users.     

桑树激光育种方法的研究

激光应用于桑树育种起于七十年代,通过我所二十多年来对桑树激光育种方法的研究与探讨,激光对桑树营养器官和生殖器官都可产生生物学效应,但这种效应的大小,多少与供试材料,供试品种和激光种类,功率大小有关,而且激光较电离辐射有它独特的优点。实践证明,激光育种与杂交育种相结合,或激光与其它理化因素相结合,处理桑树的无性器官冬芽能产生较多的有益突变,为桑树激光育种的最佳途径。     

Enhancement of monoclonal antibody production in CHO cells by exposure to He–Ne laser radiation

This study tested the effectiveness of laser biostimulation in small-scale cultures in vitro. We investigated the response of recombinant CHO cells, which are used for the production of monoclonal antibody, to low level laser radiation. The cells were irradiated using a 632.8 nm He–Ne laser in a continuous wave mode at different energy doses. We incubated the irradiated cells in small batch cultures and assessed their proliferation and productivity at various time intervals. Compared to untreated cells, the irradiated cells showed a significant increase in antibody production. Moreover, the results showed that laser irradiation did not affect viability and slightly enhanced proliferation rate.     

Screening for Gastric Sensory Motor Abnormalities in Pediatric Patients With Type 1 Diabetes

ObjectiveTo determine the frequency of gastric sensory motor symptoms in youth with type 1 diabetes.MethodsA prospective cross-sectional study was performed to evaluate symptoms of delayed gastric emptying in participants with type 1 diabetes, aged 12 to 25 years, using the Gastroparesis Cardinal Symptom Index (GCSI) questionnaire. In addition, a 5-year (January 2015 to December 2019), a retrospective study was completed on all gastric emptying scans performed in youth at our institution.ResultsA total of 359 participants (mean age, 17.7 ± 3.33 years) with type 1 diabetes completed the GCSI questionnaire. Compared with nonresponders, responders were more likely to be non-Hispanic White (90% vs 86%; P =.003) and female patients (58% vs 44%; P <.0001), with a lower HbA1c (8.1 ± 1.8 vs 9.0 ± 2.1; P <.0001). At least 1 gastrointestinal symptom was reported in 270 (75%) of responders, of which nausea was the most common (71%). A GCSI score of ≥1.9 suggestive of more severe gastrointestinal symptoms was reported in 17% of responders. Participants with scores ≥1.9 were older (19.1 ± 3.0 vs 17.8 ± 3.3 years; P =.01). In the retrospective study, 778 underwent gastric emptying scan, 29 participants had type 1 diabetes and 11 (38%) showed delayed gastric emptying.ConclusionGastrointestinal symptoms related to gastric sensory motor abnormalities are seen in youth and young adults with type 1 diabetes. In particular, for those with higher GCSI scores, earlier recognition and referral may be warranted.     

RNA Isolation from Cell Specific Subpopulations Using Laser-capture Microdissection Combined with Rapid Immunolabeling

Laser capture microdissection (LCM) allows the isolation of specific cells from thin tissue sections with high spatial resolution. Effective LCM requires precise identification of cells subpopulations from a heterogeneous tissue. Identification of cells of interest for LCM is usually based on morphological criteria or on fluorescent protein reporters. The combination of LCM and rapid immunolabeling offers an alternative and efficient means to visualize specific cell types and to isolate them from surrounding tissue. High-quality RNA can then be extracted from a pure cell population and further processed for downstream applications, including RNA-sequencing, microarray or qRT-PCR. This approach has been previously performed and briefly described in few publications. The goal of this article is to illustrate how to perform rapid immunolabeling of a cell population while keeping RNA integrity, and how to isolate these specific cells using LCM. Herein, we illustrated this multi-step procedure by immunolabeling and capturing dopaminergic cells in brain tissue from one-day-old mice. We highlight key critical steps that deserve special consideration. This protocol can be adapted to a variety of tissues and cells of interest. Researchers from different fields will likely benefit from the demonstration of this approach.     

Association of Physical Activity and Visceral Adipose Tissue in Older Women and Men

Objective: Physical inactivity, abdominal fat, and age are known risk factors for diabetes, cardiovascular disease, and certain cancers. Previous evidence supports an inverse relationship between physical activity (PA) and abdominal fat estimated by waist circumference. However, few investigations used computed tomography (CAT) scanning for precise measures of abdominal fat. Research Methods and Procedures: Sixty-five female and 106 male (age, 64.5 ± 5.2 years) participants in the Prostate, Lung, Colon and Ovarian Cancer Screening Trial underwent a cross-sectional L4–L5 CAT scan to differentiate visceral adipose tissue (VAT). Subjects were also interviewed by phone to determine PA and physical difficulties (PD). Results: Women had lower VAT (170 ± 84 vs. 205 ± 95 cm², p = 0.014), lower VAT/total fat (29.9 ± 7.2% vs. 42.6 ± 10.2%, p < 0.001), and higher total fat (596 ± 385 vs. 482 ± 183 cm², p = 0.010) than men. PA was inversely correlated to VAT (r = −0.164, p = 0.034) and total fat (r = −0.231, p = 0.003) in men and women. Those who reported a PD had higher VAT (249 vs. 180 cm², p < 0.001) and total fat (652 vs. 500 cm², p = 0.008). Multiple regression analysis indicated total PA and PD were independently associated to VAT and total fat. Discussion: This investigation suggests a beneficial effect of PA and a negative influence of PD on abdominal fat accumulation. Although the cross-sectional design limits cause-effect designations, these results are consistent with other studies showing PA/abdominal fat relation.     

Laser Raman study of internally perfused muscle fibers effect of Mg2+, ATP and Ca2+

Raman spectra of an intact muscle fiber and of internally perfused fibers in capillary tubes have been obtained. The use of internal perfusion has insured a good control of the concentration of Ca²⁺, Mg²⁺ and ATP. The comparaison of the spectra obtained with the two types of fibers shows that the muscle structure is well preserved in capillary tubes. In addition, it appears that the sarcomere length has no significant effect on the Raman spectrum of muscle fibers. Our results on perfused fibers demonstrate that a fiber can be kept in the relaxed state for several hours, then displaying an intact fiber spectrum, when the concentration of ATP, Mg²⁺ and Ca²⁺ is maintained at 5, 2 and 0 mM, respectively. Therefore ATP and Mg²⁺ do not affect the Raman spectrum of muscle fibers. When one of these components is removed, or when Ca²⁺ is added, contraction occurs and causes major spectral changes. These results are interpreted as being due to strong electrostatic interactions between basic and acidic residues during contraction, and to a change of the α-helical content, or of the orientation, of some of the contractile proteins.     

Fungal endophyte diversity in tundra grasses increases by grazing

Fungal endophytes are species rich and ubiquitous, yet, apart from the genus Epichloë, their ecology is largely unknown. Here we explore how herbivores affect the diversity of fungal endophytes in tundra grasslands. We assess both hyphal morphological and taxonomic diversity in grass individuals.By microscopic examination we identified endophytes to be present in all sampled grass individuals whereas identification to taxonomic units were only achieved in a subset of the individuals using laser micro dissection pressure catapulting and culturing for endophyte isolation. Hyphal morphological diversity was significantly higher in grasses exposed to grazing, along with 45 % more taxonomic units achieved.Our results suggest that grazing is an important mediator of fungal endophyte diversity in tundra grasslands. Furthermore, we suggest laser dissection of stained endophytes as a method for further exploring the ecological role of fungal endophytes.     

激光肺组织轻创伤手术动物实验研究

为探讨ＣＯ２激光进行肺组织轻创手术效果，本实验采用１０只离体猪肺，１００ＷＣＯ２激光进行直接照射；另用１０只杂交犬在全麻、气管插管条件下进行激光照射，初步摸索出激光肺组织轻创伤手术步骤。实验犬饲养３￣６个月后处死，肺组织病理，ＨＥ染色，气化形成的空洞，８例空洞消失，２例有由纤维结缔组织增生形成腔壁的空腔。结果ＣＯ２激光肺组织轻创伤手术是一种安全、创伤小的手术，是一种可以融诊断、治疗；融激光直接气化