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Over the course of more than a decade, space biology investigations have consistently indicated that cell wall remodeling occurs in a variety of spaceflight-grown plants. Here, we describe a mass spectrometric method to study the fundamental composition of xyloglucan, the most abundant hemicellulose in dicot cell walls, in space-grown plants. Four representative Arabidopsis root samples, from a previously conducted spaceflight experiment - Advanced Plant EXperiment - 04 (APEX-04), were used to investigate changes in xyloglucan oligosaccharides abundances in spaceflight-grown plants compared to ground controls. In situlocalized enzymatic digestions and surface sampling mass spectrometry analysis provided spatial resolution of the changes in xyloglucan oligosaccharides abundances. Overall, the results showed that oligosaccharide XXLG/XLXG and XXFG branching patterns were more abundant in the lateral roots of spaceflight-grown plants, while XXXG, XLFG, and XLFG/XLFG were more abundant in the lateral roots of ground control plants. In the primary roots, XXFG had a higher abundance in ground controls than in spaceflight plants. This methodology of analyzing the basic components of the cell wall in this paper highlights two important findings. First, that are differences in the composition of xyloglucan oligosaccharides in spaceflight root cell walls compared to ground controls and, second, most of these differences are observed in the lateral roots. Thus, the methodology described in this paper provides insights into spaceflight cell wall modifications for future investigations.

Background: Breast cancer is one of the leading cancers in women in the Western world. Cancer treatment, especially chemotherapy, is often associated with physical and psychosocial side effects. Objective: To improve the quality of life and manage side effects, a new integrative mind-body-medicine group concept for breast cancer patients receiving chemotherapy was developed and pilot tested. Methods: Breast cancer patients participated in a 66 hours mind-body-medicine group program tailored to the needs of cancer patients during chemotherapy. The program was integrated into standard care encompassing mindfulness training, yoga, moderate exercise, nutrition, complementary self-help strategies, cognitive restructuring, and acupuncture. Quality of life (EORTC QLQ-C30), depression and anxiety (HADS), stress (PSS-10), and fatigue (BFI) were assessed before and after the program, as well as satisfaction and safety. Analyses were carried out on exploratory basis with paired samples t-tests. Results: Fifty-seven female patients, aged 51.3±10.5 years, with breast cancer diagnoses were enrolled. After completing the program, global EORTC quality of life was improved (D=9.5; 95%-CI=[2.9|16.1]; p=.005), although the EORTC-symptom scales assessing fatigue (D=9.9; 95%-CI=[1|18.8]; p=.030), nausea (D=7.1; 95%- CI=[0.6|13.6]; p=.031), and dyspnea (D=12.5; 95%-CI=[2.9|22.1]; p=.011) were found to be increased. Stress (D=-3.5; 95%-CI=[-5|-2.1]; p=.000), anxiety (D=-3.8; 95%-CI=[-4.9|-2.7]; p=.000) and depression (D=-3.9; 95%-CI=[-4.9|-2.8]; p=.000) were also found to be significantly reduced. Regarding the severity of (D=0.2; 95%- CI=[-0.8|0.5]; p=.644) and the impairment due to fatigue (D=0.1; 95%-CI=[-0.8|0.6]; p=.696), no significant worsening was observed. Patients were satisfied with the program. No serious adverse events were reported. Conclusion: Breast cancer patients benefit from an integrative mind-body-medicine group program during chemotherapy regarding the quality of life and psychological symptoms. Randomized controlled trials are warranted.

The concept of using informative wavelength imagery to monitor plant health and ecosystem stability from space is derived from the deployment of Landsat and the development of the Normalized Difference Vegetative Index, or NDVI. NDVI presents the relative reflectance of the Near IR from plant leaves as a measure of relative plant health in terrestrial habitats and landscapes. However, the use of NDVI and NDVI-like imagery is rapidly evolving toward higher spatial resolution and more localized assessments of plant health, such as the use of drone imagery to monitor outdoor farms, and the use of mounted cameras within indoor growing facilities. With the advancement of plant growth systems in support of human space exploration, especially to the moon and Mars, remote assessment of plant health within exploration habitats becomes a critical element for development. This project examines the deployment of NDVI-like capabilities within a planetary analog greenhouse on the Antarctic ice shelf. The EDEN ISS Antarctica project provides a case study on the practical use of specific wavelength imagery to monitor plant health within space exploration environments. GoPro cameras, modified to dual bandpass capabilities, provided Single Image NDVI analyses for a year within the EDEN ISS Future Exploration Greenhouse at the Neumayer Station III in Antarctica. Images were acquired on site, analyzed remotely, and archived for the entire duration of the deployment through a combination of back-room science activities and operational communications with the Neumayer Station III. The results provide insights into the potential use of specific imaging wavelengths to enhance crop production in space exploration.

Fluorescent imaging offers the ability to monitor biological functions, in this case biological responses to space-related environments. For plants, fluorescent imaging can include general health indicators such as chlorophyll fluorescence as well as specific metabolic indicators such as engineered fluorescent reporters. This paper describes the Flex Imager a fluorescent imaging payload designed for Middeck Locker deployment and now tested on multiple flight and flight-related platforms. The Flex Imager and associated payload elements have been developed with a focus on ‘flexibility’ allowing for multiple imaging modalities and change-out of individual imaging or control components in the field. The imaging platform is contained within the standard Middeck Locker spaceflight form factor, with components affixed to a baseplate that permits easy rearrangement and fine adjustment of components. The Flex Imager utilizes standard software packages to simplify operation, operator training, and evaluation by flight provider flight test engineers, or by researchers processing the raw data. Images are obtained using a commercial cooled CCD image sensor, with light-emitting diodes for excitation and a suite of filters that allow biological samples to be imaged over wavelength bands of interest. Although baselined for the monitoring of green fluorescent protein and chlorophyll fluorescence from Arabidopsis samples, the Flex Imager payload permits imaging of any biological sample contained within a standard 10 cm by 10 cm square Petri plate. A sample holder was developed to secure sample plates under different flight profiles while permitting sample change-out should crewed operations be possible. In addition to crew-directed imaging, autonomous or telemetric operation of the payload is also a viable operational mode. An infrared camera has also been integrated into the Flex Imager payload to allow concurrent fluorescent and thermal imaging of samples. The Flex Imager has been utilized to assess, in real-time, the response of plants to novel environments including various spaceflight analogs, including several parabolic flight environments as well as hypobaric plant growth chambers. Basic performance results obtained under these operational environments, as well as laboratory-based tests are described. The Flex Imager has also been designed to be compatible with emerging suborbital platforms.

The level of bone-conducted sound in the auditory meatus is increased at low frequencies by occlusion of the meatus, for example, by the earmold of a hearing aid (HA). Physical measures of this “occlusion effect” (OE) require vibration of the skull. In previous research, either self-voicing or audiometric bone conduction vibrators were used to produce this vibration, with the result that the OE could not be measured for frequencies below 125 Hz. However, frequencies below this can be important for music perception by HA users. The objective was to develop and evaluate a method that gives a lower-bound estimate of the OE for frequencies below 125 Hz.

The 14-3-3 family of proteins is well known for participating in signal transduction by binding specifically phosphorylated proteins, thereby completing their kinase-induced transition in activity or localization. This interaction-based modulation of signal flux through metabolic pathways is a critical feature of many important eukaryotic signal transduction cascades. Only recently, however, have studies in Arabidopsis thalianadescribed that some of the most fundamental plant signal transduction pathways, including the photoperiodic flowering pathway, are functionally affected by 14-3-3s. There are pivotal points in the photoperiod pathway that are characterized by the accumulation, localization and stability of critical protein factors, all of which are strongly affected by light quality and photoperiod duration. These mechanisms (localization, phosphorylation, regulated proteolysis) are the same as those regulated by 14-3-3 proteins in other systems. Yet it is only recently that well characterized 14-3-3 genetic tools have become available in sufficient diversity to make it possible to truly tie 14-3-3 interactions to light signaling and flowering. This review presents an overview of photoperiodic flowering signaling and direct 14-3-3 participation in the process, coupled with a discussion of the overlapping and specific roles of 14-3-3s which present confounding issues in the functional dissection of this family of signaling proteins.

Understanding how hypobaria can affect net photosynthetic (Pnet) and net evapotranspiration rates of plants is important for the Mars Exploration Program because low-pressured environments may be used to reduce the equivalent system mass of near-term plant biology experiments on landers or future bioregenerative advanced life support systems. Furthermore, introductions of plants to the surface of a partially terraformed Mars will be constrained by the limits of sustainable growth and reproduction of plants to hypobaric conditions. To explore the effects of hypobaria on plant physiology, a low-pressure growth chamber (LPGC) was constructed that maintained hypobaric environments capable of supporting short-term plant physiological studies. Experiments were conducted on Arabidopsis thaliana maintained in the LPGC with total atmospheric pressures set at 101 (Earth sea-level control), 75, 50, 25 or 10 kPa. Plants were grown in a separate incubator at 101 kPa for 6 weeks, transferred to the LPGC, and acclimated to low-pressure atmospheres for either 1 or 16 h. After 1 or 16 h of acclimation, CO2 levels were allowed to drawdown from 0.1 kPa to CO2 compensation points to assess Pnet rates under different hypobaric conditions. Results showed that Pnet increased as the pressures decreased from 101 to 10 kPa when CO2 partial pressure (pp) values were below 0.04 kPa (i.e., when ppCO2 was considered limiting). In contrast, when ppCO2 was in the nonlimiting range from 0.10 to 0.07 kPa, the Pnet rates were insensitive to decreasing pressures. Thus, if CO2 concentrations can be kept elevated in hypobaric plant growth modules or on the surface of a partially terraformed Mars, Pnet rates may be relatively unaffected by hypobaria. Results support the conclusions that (i) hypobaric plant growth modules might be operated around 10 kPa without undue inhibition of photosynthesis and (ii) terraforming efforts on Mars might require a surface pressure of at least 10 kPa (100 mb) for normal growth of deployed plant species.

In most higher eukaryotes, the predominantly phosphoprotein-binding 14-3-3 proteins are the products of a multigene family, with many organisms having 10 or more family members. However, current models for 14-3-3/phosphopeptide interactions suggest that there is little specificity among 14-3-3s for diverse phosphopeptide clients. Therefore, the existence of sequence diversity among 14-3-3s within a single organism begs questions regarding the in vivo specificities of the interactions between the various 14-3-3s and their clients. Chief among those questions is, Do the different 14-3-3 isoforms interact with different clients within the same cell? Although the members of the Arabidopsis14-3-3 family of proteins typically contain highly conserved regions of sequence, they also display distinctive variability with deep evolutionary roots. In the current study, a survey of several Arabidopsis14-3-3/GFP fusions revealed that 14-3-3s demonstrate distinct and differential patterns of subcellular distribution, by using trichomes and stomate guard cells as in vivo experimental cellular contexts. The effects of client interaction on 14-3-3 localization were further analyzed by disrupting the partnering with peptide and chemical agents. Results indicate that 14-3-3 localization is both isoform specific and highly dependent upon interaction with cellular clients.

Chromatin structure plays a variety of roles in eukaryotes, ranging from the structural organization of the genome to the facilitation of transcription factors and remodeling of individual gene promoters. Higher-order chromatin structure typically refers to those structural features of the genome that serve to facilitate large-scale condensation and packaging. It is becoming increasingly clear, however, that large-scale features that create loop domains play an important role in the management and functional organization of the genome as well. Recently, plant models have made significant contributions to our understanding of higher-order chromatin structures in eukaryotes.

Z-DNA is a left-handed helix which can form within tracts of alternating purines and pyrimidines. Tracts of potential Z-DNA identified by sequence inspection are often noted within regulatory portions of genes, but evidence that these tracts of sequence actually exist as Z-DNA is very limited, and not available for any plant gene. In this study, the chemical probes osmium tetroxide, diethylpyrocarbonate and hydroxylamine were used to show that a tract of alternating purines and pyrimidines in the Adh1 promoter (from -311 to -325) actually assumes a Z-DNA conformation under superhelical stress in vitro.

New data from permeabilized protoplasts have expanded our view of the 5' DNase I hypersensitive area of the Arabidopsis Adh gene derived from nuclei. DNase I hypersensitivity analyses conducted with permeabilized protoplasts from Arabidopsis cell cultures indicates that there are four distinct sites of hypersensitivity centered around positions −425, −325, −200, and −60. The hypersensitive site at −200 coincides with an in vitro hypersensitive site created by purified transcription factors bound to a G-box element. The G-box is a functional cis element that plays a role in the signal transduction of hypoxia and other stresses in Adh. The data presented in this paper support the notion that G-box-related elements may also play a role in defining chromatin structure. The new Arabidopsis data are discussed within the context of what is known about the chromatin structures and regulation of two other plant Adh genes; maize Adh1 and Adh2. The chromatin of the maize Adh1 promoter is divided into a region that is constitutively hypersensitive to DNase I (−700 to −160) and an inducibly hypersensitive region (−140 and −40). There are several sequence elements within the hypersensitive regions bound by proteins in vivo. The anaerobic response element is the most well characterized and functions in the detection of hypoxia. The maize Adh2 gene promoter is constitutively hypersensitive to DNase I, with the exception of a small region that extends to include the TATA box as the gene becomes active. Several cis elements in the Adh2 promoter are bound by factors in vivo. One, at −160, is a functional element that acts as an activator in vascular tissue. The overall goal of our research with the Adh genes from maize and Arabidopsis is to gain further insight into the relationships between the regulation of gene transcription and chromatin structure in plants as it is clear that all the necessary components that characterize regulated gene activity may not be found simply by elucidating the linear sequence of nucleotides that lie 5' to the protein coding regions and finding proteins capable of binding the promoter in vitro. Dev. Genet. 22:7–16, 1998. © 1998 Wiley-Liss, Inc.

DNase-I-hypersensitive sites have been characterized in a plant gene, maize Adh1(which encodes alcohol dehydrogenase 1). It has been generally recognized in animal genes that the chromatin of the 5′ flanking region can be characterized by the accessibility of its DNA to the nuclease DNase I (EC 3.1.21.1), indicating which areas in the promoter are “open” to nuclear factors. The 5′ region of the maize Adh1gene contains two distinct DNase-I-hypersensitive regions, one constitutively present from position -160 to -700 and one that is anaerobically induced from position -35 to -150. The constitutive region contains three major hypersensitive sites, one of which corresponds in part to a region of potential Z-DNA. The induced hypersensitive region includes TATAA at -38 and CAAT at -100 as well as other potential regulatory sequences.

Osmium tetroxide (OsO4) reacts with the thymine residues of double-stranded DNA, but thymines that are unpaired or under torsional stress are hyperreactive. Although OsO4 hyperreactivity has been primarily utilized to identify Z-DNA structures in supercoiled plasmids, OsO4 will also identify other torsional perturbations of DNA. In this study, OsO4 was used to footprint an AT-rich region (between -780 and -500) of the maizeAdh1 promoter. Hyperreactive sites were identified bothin vitro andin vivo in an area that coincides with AT motifs similar to those found in scaffold attachment regions. Further, the region of OsO4 hyperreactivity lies within a fragment of DNA that is associated with the nuclear scaffold in histone-depleted nuclei.

It has been demonstrated that 14‐3‐3 proteins are present in the nuclei of Arabidopsis thalianaand Zea mayscells using laser scanning confocal microscopy and immunocytochemistry with monoclonal antibodies against plant 14‐3‐3 proteins. Confirmation of nuclear localization provides insight into the range of functions normally attributed to 14‐3‐3 proteins, especially since the association of 14‐3‐3s with transcription factors is (thus far) a phenomenon unique to plants, and since 14‐3‐3 proteins do not possess a recognizable nuclear targeting sequence.

The article discusses on developing the interest in children to become avid readers and encouraging children to read for pleasure. As said, a child becoming keen reader is related to external environment around the child rather than innate predisposition towards reading. As discussed, now-a-days education is treated as a commodity, which can give profitable return.

Members of the 14-3-3 family of proteins participate in signal transduction by modulating flux through various pathways. Potential subfunctionalization within this family has produced a suite of related proteins with diverse client interactions and discrete localization. The associated study assesses the biological roles of two specific 14-3-3 isoforms, using genetic, biochemical and physiological assays to ascertain potential nodes of interaction. Arabidopsis T-DNA insertion mutants representing the υ and µ isoforms exhibited a short, yet clear delay in flowering time on long days. Tests of hypocotyl growth inhibition under narrow bandwidth light indicated a hyposensitivity to red light, while responses to blue and far-red light were normal. These physiological tests suggest a mechanistic link between 14-3-3 proteins, red light sensing, and the pathways that control photoperiodic flowering. The precise entry point into the pathway was assessed using yeast two hybrid assays targeted against specific proteins active in the circadian oscillator, light transduction and photoperiodic flowering. Yeast two hybrid interaction was observed with CONSTANS (CO), and then confirmed with co-immunoprecipitation. Functional interaction with phyB leading to defects in flowering time and direct interaction with CONSTANS circumstantially places these specific 14-3-3 isoforms into the pathway that regulates the transition between vegetative and floral development.

Depending on the Cobalt ligand used (dppp or dppe), cyclobutene derivatives [cf.(III)] or Alder‐ene products [cf.(VIII)] arise with changing ratios, sometimes as a single product [cf.(V)].

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.