bluuebunny/crossref_metadata_2025 huggingface dataset:
Low-dose Bisphenol-A Promotes Epigenetic Changes at Pparγ Promoter in Adipose Precursor Cells
Authors: Longo Michele , Zatterale Federica , Naderi Jamal , Nigro Cecilia , Oriente Francesco , Formisano Pietro , Miele Claudia , Beguinot Francesco
Published: November 2020

Exposure to endocrine-disrupting chemicals such as Bisphenol-A (BPA) is associated with an increase in obesity prevalence. Diet is the primary cause of human exposure to this contaminant. BPA promotes obesity by inducing adipocyte dysfunction and altering adipogenesis. Contradictory evidence and unanswered questions are reported in the literature concerning the BPA effects on adipogenesis. To clarify this issue, we tested the effects of prolonged low-dose BPA exposure on different phases of adipogenesis in committed 3T3L1 and uncommitted NIH3T3 preadipocytes. Our findings show that BPA effects on the adipogenesis are mediated by epigenetic mechanisms by reducing peroxisome proliferator-activated receptor gamma (Pparγ) promoter methylation in preadipocytes. Nevertheless, in BPA-exposed 3T3L1, Pparγ expression only transiently increases as lipid accumulation at day 4 of differentiation, without altering the adipogenic potential of the precursor cells. In the absence of differentiation mix, BPA does not make the 3T3L1 an in vitro model of spontaneous adipogenesis and the effects on the Pparγ expression are still limited at day 4 of differentiation. Furthermore, BPA exposure does not commit the NIH3T3 to the adipocyte lineage, although Pparγ overexpression is more evident both in preadipocytes and during the adipocyte differentiation. Interestingly, termination of the BPA exposure restores the Pparγ promoter methylation and inflammatory profile of the 3T3L1 cells. This study shows that BPA induces epigenetic changes in a key adipogenic gene. These modifications are reversible and do not affect preadipocyte commitment and/or differentiation. We identify an alternative transcriptional mechanism by which BPA affects gene expression and demonstrate how the challenge of preventing exposure is fundamental for human health.
Molecular Characteristics of Rickettsia in Ticks Collected along the Southern Border of Mongolia
Authors: von Fricken Michael E. , Voorhees Matthew A. , Koehler Jeffrey W. , Asbun Carmen , Lam Brandon , Qurollo Barbara , Hogan Kathryn M. , Baasandagva Uyanga , Jigjav Battsetseg , Schoepp Randal J.
Published: November 2020

Tick-borne infections are a significant threat to public health, particularly in regions where individuals frequently enter tick habitats. Roughly 26% of the population in Mongolia practice nomadic pastoralism and are considered at high risk of exposure to ticks and the diseases they carry. This study tested ticks from Mongolia’s southern border for Rickettsia spp. to better understand the epidemiology of tick-borne diseases in the region. Dermacentor nuttalli and Hyalomma asiaticum ticks (n = 4022) were pooled and tested for Rickettsia spp. by real-time PCR. Melt-curve analyses and Sanger sequencing were used to identify Rickettsia species. Approximately 64% of the 786 tick pools tested positive for Rickettsia bacteria. Melt curve analyses identified four different Rickettsia species circulating in these tick pools. Amplicon sequencing of the ompA gene identified Rickettsia spp. that closely resembled R. raoultii and R. sibirica. Dermacentor nuttalli ticks from Govi-Altai had the highest maximum likelihood estimation infection rate 48.4% (95% CI: 41.7–56.5%), while Hyalommaasiaticum collected in Omnogovi had a rate of 7.6% (95% CI: 6.2–9.2%). The high detection of Rickettsia suggests a substantial risk of infection in southern Mongolia. Further studies are necessary to investigate the clinical burden of tick-borne diseases in Mongolia.
Porphyromonas gingivalis and Its Systemic Impact: Current Status
Authors: Mei Feng , Xie Mengru , Huang Xiaofei , Long Yanlin , Lu Xiaofeng , Wang Xiaoli , Chen Lili
Published: November 2020

The relationship between periodontitis and systemic diseases, notably including atherosclerosis and diabetes, has been studied for several years. Porphyromonas gingivalis, a prominent component of oral microorganism communities, is the main pathogen that causes periodontitis. As a result of the extensive analysis of this organism, the evidence of its connection to systemic diseases has become more apparent over the last decade. A significant amount of research has explored the role of Porphyromonas gingivalis in atherosclerosis, Alzheimer’s disease, rheumatoid arthritis, diabetes, and adverse pregnancy outcomes, while relatively few studies have examined its contribution to respiratory diseases, nonalcoholic fatty liver disease, and depression. Here, we provide an overview of the current state of knowledge about Porphyromonas gingivalis and its systemic impact in an aim to inform readers of the existing epidemiological evidence and the most recent preclinical studies. Additionally, the possible mechanisms by which Porphyromonas gingivalis is involved in the onset or exacerbation of diseases, together with its effects on systemic health, are covered. Although a few results remain controversial, it is now evident that Porphyromonas gingivalis should be regarded as a modifiable factor for several diseases.
A Novel Subunit Vaccine Based on Outer Capsid Proteins of Grass Carp Reovirus (GCRV) Provides Protective Immunity against GCRV Infection in Rare Minnow (Gobiocypris rarus)
Authors: Mu Changyong , Vakharia Vikram N. , Zhou Yong , Jiang Nan , Liu Wenzhi , Meng Yan , Li Yiqun , Xue Mingyang , Zhang Jieming , Zeng Lingbing , Zhong Qiwang , Fan Yuding
Published: November 2020

The grass carp hemorrhagic disease, caused by the grass carp reovirus (GCRV), has resulted in severe economic losses in the aquaculture industry in China. VP4 and VP35 are outer capsid proteins of GCRV and can induce an immune response in the host. Here, three recombinant baculoviruses, AcMNPV-VP35, AcMNPV-VP4, and AcMNPV-VP35-VP4, were generated to express recombinant VP4 and VP35 proteins from GCRV type II in insect cells by using the Bac-to-Bac baculovirus expression system to create a novel subunit vaccine. The expression of recombinant VP35, VP4, and VP35-VP4 proteins in Sf-9 cells were confirmed by Western blotting and immunofluorescence. Recombinant VP35, VP4, and VP35-VP4 were purified from baculovirus-infected cell lysates and injected intraperitoneally (3 μg/fish) into the model rare minnow, Gobiocypris rarus. After 21 days, the immunized fish were challenged with virulent GCRV. Liver, spleen, and kidney samples were collected at different time intervals to evaluate the protective efficacy of the subunit vaccines. The mRNA expression levels of some immune-related genes detected by using quantitative real-time PCR (qRT-PCR) were significantly upregulated in the liver, spleen, and kidney, with higher expression levels in the VP35-VP4 group. The nonvaccinated fish group showed 100% mortality, whereas the VP35-VP4, VP4, and VP35 groups exhibited 67%, 60%, and 33% survival, respectively. In conclusion, our results revealed that recombinant VP35 and VP4 can induce immunity and protect against GCRV infection, with their combined use providing the best effect. Therefore, VP35 and VP4 proteins can be used as a novel subunit vaccine against GCRV infection.
Effect of Non-Concentrated and Concentrated Vaporized Hydrogen Peroxide on Scrapie Prions
Authors: Sakudo Akikazu , Yamashiro Risa , Harata Chihiro
Published: November 2020

To date, there have been no studies on the sterilization of prions by non-concentrated and concentrated vaporized hydrogen peroxide (VHP) applied by the same instrument. Here, the effect of the two types of VHP applied using an ES-700 sterilizer on prions was investigated. Brain homogenate from scrapie (Chandler) prion-infected mice was spotted on a cover glass and subjected to ES-700 treatment in soft (non-concentrated VHP from 59% hydrogen peroxide) or standard (concentrated VHP from 80% hydrogen peroxide) mode. Proteinase K-resistant prion protein (PrPres), an indicator of the abnormal isoform of prion protein (PrPSc), was reduced by ES-700 treatment under several conditions: SFT1/4 (soft mode, quarter cycle), SFT1/2 (soft mode, half cycle), SFT1 (soft mode, full cycle), and STD1/2 (standard mode, half cycle). PrPres was detected after the first and second rounds of protein misfolding cyclic amplification (PMCA) of untreated samples, but was undetectable in SFT1/4, SFT1/2, SFT1, and STD1/2 treated samples. In a mouse bioassay, SFT1/2 and STD1/2 treatment of prions significantly prolonged survival time, suggesting that prion infectivity is reduced after ES-700 treatment. In summary, both non-concentrated and concentrated VHP inactivate prions and may be useful for the low-temperature sterilization of prion-contaminated medical devices.
The Challenges of a Children’s Hospital during the COVID-19 Pandemic: The Pediatric Surgeon’s Point of View
Authors: Pelizzo Gloria , Costanzo Sara , Maestri Luciano , Selvaggio Giorgio Giuseppe Orlando , Pansini Andrea , Zuccotti Gian Vincenzo , Zoia Elena , De Filippis Giuseppe , Visconti Alessandro , Calcaterra Valeria
Published: November 2020

During the coronavirus disease of 2019 (COVID-19) emergency, in the pediatric surgical setting, it has been essential to avoid and contain infections as well as to protect both the patients and the surgical team. During this emergency, procedures and workflow were adapted to provide the safest possible environment for both the surgical team and the patients. Pediatric surgical activities were reorganized during the COVID-19 pandemic at the “Vittore Buzzi” Children’s Hospital, which is a pediatric/maternal hospital located in Milan (Lombardy Region), Italy. Resources were optimized in order to maintain high levels of care and quality of assistance. During the COVID-19 emergency, the pediatric surgical department at the “Vittore Buzzi” Children’s Hospital became an acute care surgical service. For the reorganization of surgical activities, institutional protocols were adapted in order to preserve the pediatric-specific characteristics of our service; five crucial points were specifically addressed. The pediatric surgical procedures carried out during the initial two months of the Italian lockdown are also reported. Continuity of care was maintained for children affected by severe diseases, such as tumors and neurosurgical conditions, whose treatment could not be deferred. Telemedicine and telecommunication were adopted as quick-support modalities for pre- and post-operative care. This reorganization allowed us to preserve the “pediatric specificity” and all care-related procedures offered at this high-quality/high-volume surgical care referral center.
Blood–Brain Barrier Modulation to Improve Glioma Drug Delivery
Authors: Luo Huilong , Shusta Eric V.
Published: November 2020

The blood–brain barrier (BBB) is formed by brain microvascular endothelial cells that are sealed by tight junctions, making it a significant obstacle for most brain therapeutics. The poor BBB penetration of newly developed therapeutics has therefore played a major role in limiting their clinical success. A particularly challenging therapeutic target is glioma, which is the most frequently occurring malignant brain tumor. Thus, to enhance therapeutic uptake in tumors, researchers have been developing strategies to modulate BBB permeability. However, most conventional BBB opening strategies are difficult to apply in the clinical setting due to their broad, non-specific modulation of the BBB, which can result in damage to normal brain tissue. In this review, we have summarized strategies that could potentially be used to selectively and efficiently modulate the tumor BBB for more effective glioma treatment.
Quality-by-Design Approach for the Development of Nano-Sized Tea Tree Oil Formulation-Impregnated Biocompatible Gel with Antimicrobial Properties
Authors: Muta Thabata , Parikh Ankit , Kathawala Krishna , Haidari Hanif , Song Yunmei , Thomas Jackson , Garg Sanjay
Published: November 2020

Despite the promising properties of tea tree oil (TTO) as potential therapeutics for several superficial skin conditions, certain limitations such as physical instability and skin irritation have restricted its widespread use. This study focuses on developing a rationally designed lipid-based nanoformulation (TTO-LNF) in accordance with the US Food and Drug Administration standard using a well-recognized quality-by-design (QbD) approach. Using a mixture experimental design, TTO-LNF has been optimized with 5% TTO, 10% surfactant, 5% co-surfactant, and 80% water, which showed a 14.4 ± 4.4 nm droplet size and 0.03 ± 0.01 polydispersity index (PDI). To ease the topical administration, the TTO-LNF gel formulation was further developed using xanthan gum to achieve the desired viscosity and form a gel. The in vitro antibacterial tests of TTO-LNF showed promising inhibitory effects toward both Gram-negative and Gram-positive bacteria. In fact, a complete growth inhibition of S. epidermidis was observed when exposed to TTO-LNF and TTO-LNF gel for 24 h, showing better activity than antibiotic kanamycin (25 µg/mL). Additionally, the in vitro release study showed a sustained release profile with a 50% release in 24 h, which could be beneficial to reduce the toxicity and thereby improve the therapeutic efficacy for long-acting applications. Furthermore, the formulations were remarkably stable at 40 °C/75% Relative humidity (RH) for at least 4 weeks. Therefore, this study presents a promising strategy to develop a biocompatible and stable formulation that can be used for the topical treatment of skin infections.
Cultural Humility: A Proposed Model for a Continuing Professional Development Program
Authors: Cox Jennifer L. , Simpson Maree Donna
Published: November 2020

Continuing professional development (CPD) is an essential component of professional practice for registered health practitioners to maintain and enhance knowledge, skills and abilities. There are many topics that practitioners may pursue relevant to their practice environment, and, in recent years, providing culturally safe and respectful practice is an emerging area of need. Unfortunately, many health professionals, whilst willing to offer cultural safe healthcare, may be uncertain of how to enact that practice. The World Health Organisation recognises attainment of the highest possible standard of health as a basic human right, and cultural safety is increasingly becoming an expectation of health professionals. To address this need and the insufficiency of support in the literature, the authors have presented a discussion paper on various aspects of cultural safety and the underlying constructs, such as cultures, that support it. The discussion takes into account core constructs that signpost the path to cultural safety and recognises the role and accountability of all levels of the healthcare system, not merely the practitioner. Finally, we propose a model program for a cultural humility CPD activity incorporating pre-work, online modules, interactive workshop, reflection on professional practice and a post-workshop evaluation.
The Game Is Not over Yet—Go in the Post-AlphaGo Era
Authors: Egri-Nagy Attila , Törmänen Antti
Published: November 2020

The game of Go was the last great challenge for artificial intelligence in abstract board games. AlphaGo was the first system to reach supremacy, and subsequent implementations further improved the state of the art. As in chess, the fall of the human world champion did not lead to the end of the game. Now, we have renewed interest in the game due to new questions that emerged in this development. How far are we from perfect play? Can humans catch up? How compressible is Go knowledge? What is the computational complexity of a perfect player? How much energy is really needed to play the game optimally? Here, we investigate these and related questions with respect to the special properties of Go (meaningful draws and extreme combinatorial complexity). Since traditional board games have an important role in human culture, our analysis is relevant in a broader context. What happens in the game world could forecast our relationship with AI entities, their explainability, and usefulness.
Non-Destructive Estimation of Total Chlorophyll Content of Apple Fruit Based on Color Feature, Spectral Data and the Most Effective Wavelengths Using Hybrid Artificial Neural Network—Imperialist Competitive Algorithm
Authors: Pourdarbani Razieh , Sabzi Sajad , Hernández-Hernández Mario , Hernández-Hernández José Luis , Gallardo-Bernal Iván , Herrera-Miranda Israel
Published: November 2020

Non-destructive assessment of the physicochemical properties of food products, especially fruits, makes it possible to examine the internal quality without any damage. This is applicable at different stages of fruit growth, harvesting stage, and storage as well as at the market stage. In this regard, the present study aimed to estimate the total chlorophyll content using three types of data: color data, spectral data, and spectral data related to the most effective wavelengths. The most important steps of the proposed algorithms include extracting spectral and color data from each sample of Fuji cultivar apple, selecting the most effective wavelengths at the range of 660–720 nm using hybrid artificial neural network–particle swarm optimization (ANN-PSO), non-destructive assessment of the chemical property of total chlorophyll content based on color data, and spectral data using hybrid artificial neural network-Imperialist competitive algorithm (ANN-ICA). In order to assess the reliability of the hybrid ANN-ICA, 1000 iterations were performed after selecting the optimal structure of the artificial neural network. According to the results, in the best training mode and using spectral data and the most effective wavelength, total chlorophyll content was predicted with the R2 and RMSE of 0.991 and 0.0035, 0.997 and 0.001, 0.997 and 0.0006, respectively.
RNA-Seq Time Series of Vitis vinifera Bud Development Reveals Correlation of Expression Patterns with the Local Temperature Profile
Authors: Pucker Boas , Schwandner Anna , Becker Sarah , Hausmann Ludger , Viehöver Prisca , Töpfer Reinhard , Weisshaar Bernd , Holtgräwe Daniela
Published: November 2020

Plants display sophisticated mechanisms to tolerate challenging environmental conditions and need to manage their ontogenesis in parallel. Here, we set out to generate an RNA-Seq time series dataset throughout grapevine (Vitis vinifera) early bud development. The expression of the developmental regulator VviAP1 served as an indicator of the progression of development. We investigated the impact of changing temperatures on gene expression levels during the time series and detected a correlation between increased temperatures and a high expression level of genes encoding heat-shock proteins. The dataset also allowed the exemplary investigation of expression patterns of genes from three transcription factor (TF) gene families, namely MADS-box, WRKY, and R2R3-MYB genes. Inspection of the expression profiles from all three TF gene families indicated that a switch in the developmental program takes place in July which coincides with increased expression of the bud dormancy marker gene VviDRM1.
Nitric Oxide Signaling in Plants
Authors: Hancock John T.
Published: November 2020

Nitric oxide (NO) is an integral part of cell signaling mechanisms in animals and plants. In plants, its enzymatic generation is still controversial. Evidence points to nitrate reductase being important, but the presence of a nitric oxide synthase-like enzyme is still contested. Regardless, NO has been shown to mediate many developmental stages in plants, and to be involved in a range of physiological responses, from stress management to stomatal aperture closure. Downstream from its generation are alterations of the actions of many cell signaling components, with post-translational modifications of proteins often being key. Here, a collection of papers embraces the differing aspects of NO metabolism in plants.
Controlling Geminiviruses before Transmission: Prospects
Authors: Mubarik Muhammad Salman , Khan Sultan Habibullah , Ahmad Aftab , Raza Ali , Khan Zulqurnain , Sajjad Muhammad , Sammour Reda Helmy Ahmed , Mustafa Abd El-Zaher M.A. , Al-Ghamdi Abdullah Ahmed , Alajmi Amal H. , Alshamasi Fatin K. I. , Elshikh Mohamed Soliman
Published: November 2020

Whitefly (Bemisia tabaci)-transmitted Geminiviruses cause serious diseases of crop plants in tropical and sub-tropical regions. Plants, animals, and their microbial symbionts have evolved complex ways to interact with each other that impact their life cycles. Blocking virus transmission by altering the biology of vector species, such as the whitefly, can be a potential approach to manage these devastating diseases. Virus transmission by insect vectors to plant hosts often involves bacterial endosymbionts. Molecular chaperonins of bacterial endosymbionts bind with virus particles and have a key role in the transmission of Geminiviruses. Hence, devising new approaches to obstruct virus transmission by manipulating bacterial endosymbionts before infection opens new avenues for viral disease control. The exploitation of bacterial endosymbiont within the insect vector would disrupt interactions among viruses, insects, and their bacterial endosymbionts. The study of this cooperating web could potentially decrease virus transmission and possibly represent an effective solution to control viral diseases in crop plants.
Cracking in Sweet Cherry Cultivars Early Bigi and Lapins: Correlation with Quality Attributes
Authors: Pereira Sandra , Silva Vânia , Bacelar Eunice , Guedes Francisco , Silva Ana Paula , Ribeiro Carlos , Gonçalves Berta
Published: November 2020

Fruit cracking is one of the main concerns in sweet cherry production and is caused by a heavy rainfall before and during the harvest. This physiological disorder leads to severe economic losses, which can be more or less effective depending on the cracked region of the fruit: in the cheeks (side cracks), in the stylar scar region, or in the stem cavity region. Sweet cherry cracking can be affected by several factors such as cultivar, growing conditions, rootstock, fruit size, flesh osmotic potential, cuticular characteristics of the skin, and stage of fruit development. In this sense, the objective of this work was to evaluate the cracking incidence in two sweet cherry cultivars (Early Bigi and Lapins grafted on “Saint Lucie 64” rootstock) and correlate the cracking index with other quality parameters. Fruits were harvested on 2 May (cv. Early Bigi) and on 27 May (cv. Lapins) 2019 at their commercial ripening stage. In the field, the total yield and the trunk cross-sectional area were determined for each tree in order to calculate the yield efficiency. In the laboratory, the cracking index was determined in 150 fruits without visual defects. In addition, fruit size and weight, wax content, flesh firmness, epidermis rupture force, total soluble solids, pH, titratable acidity, and maturity index of 30 fruits were also evaluated. In general, all the analyzed quality parameters were influenced by the cultivar, being that cv. Lapins presented larger, heavier, firmer, and sweeter fruits, with more acidity and higher maturation index. However, cv. Lapins also presented higher cracking index, which was positively correlated with all the parameters above-mentioned and negatively correlated with the wax content. In fact, cv. Early Bigi presented a high wax content and simultaneously a low cracking index. The stylar scar region cracks were the most prevalent in both cultivars. These results allowed us to conclude that, in the North Portugal region, the Lapins cherries presented better quality attributes than the Early Bigi cherries. However, the latter are still very valuable to the region due to its early ripening. Additionally, it was also possible to conclude that bigger, firmer, more mature, and with lower wax content cherries were more sensitive to cracking than the smaller fruits, soft-fleshed, less mature, and with higher wax content.
Morpho-Physiological and Molecular Evaluation of Drought and Recovery in Impatiens walleriana Grown Ex Vitro
Authors: Đurić Marija , Subotić Angelina , Prokić Ljiljana , Trifunović-Momčilov Milana , Cingel Aleksandar , Vujičić Milorad , Milošević Snežana
Published: November 2020

This study was carried out to examine the drought effect on development, physiological, biochemical and molecular parameters in Impatiens walleriana grown ex vitro. Experiment design included three treatments: Control plants—grown under optimal watering (35%–37% of soil moisture content), drought-stressed plants—non-irrigated to reach 15% and 5% of soil moisture content and recovery plants—rehydrated for four days to reach optimal soil moisture content. Drought reduced fresh weight, total leaf area, as well as dry weight of I. walleriana shoots. Drought up-regulated expression of abscisic acid (ABA) biosynthesis genes 9-cis-epoxycarotenoid dioxygenase 4 (NCED4) and abscisic aldehyde oxidase 2 (AAO2) and catabolic gene ABA 8′-hydroxylase 3 (ABA8ox3) which was followed by increased ABA content in the leaves. Decrement in water potential of shoots during the drought was not accompanied with increased amino acid proline content. We detected an increase in chlorophyll, carotenoid, total polyphenols and flavonols content under drought conditions, as well as malondialdehyde, hydrogen peroxide and DPPH (1,1′-diphenyl-2-picrylhydrazyl) activity. Increased antioxidant enzyme activities (superoxide dismutase, peroxidase and catalase) throughout drought were also determined. Recovery treatment was significant for neutralizing drought effect on growth parameters, shoot water potential, proline content and genes expression.
Loquat (Eriobotrya japonica) Is a New Natural Host of Apple Stem Pitting Virus
Authors: Morán Félix , Canales Celia , Olmos Antonio , Ruiz-García Ana
Published: November 2020

Loquat (Eriobotrya japonica) is a minor but important woody crop cultivated in Asia and Europe. High-throughput sequencing (HTS) analysis of an asymptomatic loquat plant using RNAseq Illumina technology has allowed the detection for the first time of apple stem pitting virus (ASPV), the type species of the genus Foveavirus in the family Betaflexiviridae, infecting this crop. A nearly complete genome of 9303 nts (ASPV-SL61) reconstructed bioinformatically shows the typical genomic structure of this viral species and a highest nucleotide identity (85.9%) with the Chinese ASPV isolate YLX from pear. A close phylogenetic relationship between ASPV-SL61 and ASPV-YLX has been confirmed by the sequence analysis of full-length ASPV genomic sequences available in the databases. In fact, a phylogenetic study based on a partial CP N-terminal sequence previously proposed to be involved in host adaptation has shown that ASPV-SL61 loquat isolate is more closely related to ASPV pear isolates. The presence of ASPV in loquat has been further confirmed by RT-PCR and Sanger sequencing and DAS-ELISA. An incidence of 15% was determined in one of the loquat Spanish growing areas. The sequence analysis of the partial CP sequences amplified by RT-PCR has shown a high level of variability between loquat isolates. To our knowledge, this is the first record of loquat as a natural host of ASPV.
Comparison of Morphological Characteristics and Determination of Different Patterns for Rubber Particles in Dandelion and Different Rubber Grass Varieties
Authors: Yuan Boxuan , Ding Guohua , Ma Junjun , Wang Lingling , Yu Li , Ruan Xueyu , Zhang Xueyan , Zhang Wangfeng , Wang Xuchu , Xie Quanliang
Published: November 2020

Russian dandelion Taraxacum kok-saghyz (TKS) is one promising alternative crop for natural rubber production. However, it is easily confused with other dandelions. In this study, we performed a systematical comparison of the morphological characteristics for different TKS varieties and common dandelion Taraxacum officinale (TO). Our results demonstrated that several obvious differences in morphology can be found between TKS and TO. TO leaf is a pinnate shape, its margin is heavily jagged and its base is cuneate, but TKS leaf is more cuneate and its leaf margin is nearly smooth and round. There are obvious differences for the outer bracts of TO and TKS flower buds. TKS bracts are oblanceolate, apex obtuse, margin smooth and sinuate, and its outer layer of flower buds and faceplate involucre sepal is buckled inward to form a certain angle. TKS is self-incompatible, and its seeds are spindle-shaped achene and show upright plumpness. A large amount of laticifer cells and rubber particles can be detected from many TKS tissues, and dry roots of TKS contain high contents of natural rubber. Laticifer cells and rubber particles can only be examined in the vein, stem, and roots of TKS. Our statical results also revealed that the numbers of laticifer cells and rubber particles have a positive relationship with the rubber content in TKS roots. These morphological features can help us to easily distinguish TKS from common dandelion and approximately estimate the rubber content in the roots of different TKS varieties for TKS breeding in future.
Arabidopsis Response to Inhibitor of Cytokinin Degradation INCYDE: Modulations of Cytokinin Signaling and Plant Proteome
Authors: Berková Veronika , Kameniarová Michaela , Ondrisková Vladěna , Berka Miroslav , Menšíková Simona , Kopecká Romana , Luklová Markéta , Novák Jan , Spíchal Lukáš , Rashotte Aaron M. , Brzobohatý Břetislav , Černý Martin
Published: November 2020

Cytokinins are multifaceted plant hormones that play crucial roles in plant interactions with the environment. Modulations in cytokinin metabolism and signaling have been successfully used for elevating plant tolerance to biotic and abiotic stressors. Here, we analyzed Arabidopsis thaliana response to INhibitor of CYtokinin DEgradation (INCYDE), a potent inhibitor of cytokinin dehydrogenase. We found that at low nanomolar concentration, the effect of INCYCE on seedling growth and development was not significantly different from that of trans-Zeatin treatment. However, an alteration in the spatial distribution of cytokinin signaling was found at low micromolar concentrations, and proteomics analysis revealed a significant impact on the molecular level. An in-depth proteome analysis of an early (24 h) response and a dose-dependent response after 168 h highlighted the effects on primary and secondary metabolism, including alterations in ribosomal subunits, RNA metabolism, modulations of proteins associated with chromatin, and the flavonoid and phenylpropanoid biosynthetic pathway. The observed attenuation in stress-response mechanisms, including abscisic acid signaling and the metabolism of jasmonates, could explain previously reported positive effects of INCYDE under mild stress conditions.
A Genetic Screen to Identify New Molecular Players Involved in Photoprotection qH in Arabidopsis thaliana
Authors: Bru Pierrick , Nanda Sanchali , Malnoë Alizée
Published: November 2020

Photosynthesis is a biological process which converts light energy into chemical energy that is used in the Calvin–Benson cycle to produce organic compounds. An excess of light can induce damage to the photosynthetic machinery. Therefore, plants have evolved photoprotective mechanisms such as non-photochemical quenching (NPQ). To focus molecular insights on slowly relaxing NPQ processes in Arabidopsis thaliana, previously, a qE-deficient line—the PsbS mutant—was mutagenized and a mutant with high and slowly relaxing NPQ was isolated. The mutated gene was named suppressor of quenching 1, or SOQ1, to describe its function. Indeed, when present, SOQ1 negatively regulates or suppresses a form of antenna NPQ that is slow to relax and is photoprotective. We have now termed this component qH and identified the plastid lipocalin, LCNP, as the effector for this energy dissipation mode to occur. Recently, we found that the relaxation of qH1, ROQH1, protein is required to turn off qH. The aim of this study is to identify new molecular players involved in photoprotection qH by a whole genome sequencing approach of chemically mutagenized Arabidopsis thaliana. We conducted an EMS-mutagenesis on the soq1 npq4 double mutant and used chlorophyll fluorescence imaging to screen for suppressors and enhancers of qH. Out of 22,000 mutagenized plants screened, the molecular players cited above were found using a mapping-by-sequencing approach. Here, we describe the phenotypic characterization of the other mutants isolated from this genetic screen and an additional 8000 plants screened. We have classified them in several classes based on their fluorescence parameters, NPQ kinetics, and pigment content. A high-throughput whole genome sequencing approach on 65 mutants will identify the causal mutations thanks to allelic mutations from having reached saturation of the genetic screen. The candidate genes could be involved in the formation or maintenance of quenching sites for qH, in the regulation of qH at the transcriptional level, or be part of the quenching site itself.
The Turnera Style S-Locus Gene TsBAHD Possesses Brassinosteroid-Inactivating Activity When Expressed in Arabidopsis thaliana
Authors: Matzke Courtney M. , Shore Joel S. , Neff Michael M. , McCubbin Andrew G.
Published: November 2020

Heterostyly distinct hermaphroditic floral morphs enforce outbreeding. Morphs differ structurally, promote cross-pollination, and physiologically block self-fertilization. In Turnera the self-incompatibility (S)-locus controlling heterostyly possesses three genes specific to short-styled morph genomes. Only one gene, TsBAHD, is expressed in pistils and this has been hypothesized to possess brassinosteroid (BR)-inactivating activity. We tested this hypothesis using heterologous expression in Arabidopsis thaliana as a bioassay, thereby assessing growth phenotype, and the impacts on the expression of endogenous genes involved in BR homeostasis and seedling photomorphogenesis. Transgenic A. thaliana expressing TsBAHD displayed phenotypes typical of BR-deficient mutants, with phenotype severity dependent on TsBAHD expression level. BAS1, which encodes an enzyme involved in BR inactivation, was downregulated in TsBAHD-expressing lines. CPD and DWF, which encode enzymes involved in BR biosynthesis, were upregulated. Hypocotyl growth of TsBAHD dwarfs responded to application of brassinolide in light and dark in a manner typical of plants over-expressing genes encoding BR-inactivating activity. These results provide empirical support for the hypothesis that TsBAHD possesses BR-inactivating activity. Further this suggests that style length in Turnera is controlled by the same mechanism (BR inactivation) as that reported for Primula, but using a different class of enzyme. This reveals interesting convergent evolution in a biochemical mechanism to regulate floral form in heterostyly.
Increased [CO2] Causes Changes in Physiological and Genetic Responses in C4 Crops: A Brief Review
Authors: Silva Renan Gonçalves da , Alves Rita de Cássia , Zingaretti Sonia Marli
Published: November 2020

Climate change not only worries government representatives and organizations, but also attracts the attention of the scientific community in different contexts. In agriculture specifically, the cultivation and productivity of crops such as sugarcane, maize, and sorghum are influenced by several environmental factors. The effects of high atmospheric concentration of carbon dioxide ([CO2]) have been the subject of research investigating the growth and development of C4 plants. Therefore, this brief review presents some of the physiological and genetic changes in economically important C4 plants following exposure periods of increased [CO2] levels. In the short term, with high [CO2], C4 plants change photosynthetic metabolism and carbohydrate production. The photosynthetic apparatus is initially improved, and some responses, such as stomatal conductance and transpiration rate, are normally maintained throughout the exposure. Protein-encoding genes related to photosynthesis, such as the enzyme phosphoenolpyruvate carboxylase, to sucrose accumulation and to biomass growth and are differentially regulated by [CO2] increase and can variably participate owing to the C4 species and/or other internal and external factors interfering in plant development. Despite the consensus among some studies, mainly on physiological changes, further studies are still necessary to identify the molecular mechanisms modulated under this condition. In addition, considering future scenarios, the combined effects of high environmental and [CO2] stresses need to be investigated so that the responses of maize, sugarcane, and sorghum are better understood.
Prostanthera (Lamiaceae) as a ‘Cradle of Incense’: Chemophenetics of Rare Essential Oils from Both New and Forgotten Australian ‘Mint Bush’ Species
Authors: Sadgrove Nicholas J. , Padilla-González Guillermo F. , Telford Ian R. H. , Greatrex Ben W. , Jones Graham L. , Andrew Rose , Bruhl Jeremy J. , Langat Moses K. , Melnikovova Ingrid , Fernandez-Cusimamani Eloy
Published: November 2020

The highly aromatic Australian mint bushes from the genus Prostanthera Labill. produce a high yield of essential oil on hydrodistillation. Together with its rich history, horticultural potential, iconic flowers, and aromatic leaves, it achieves high ornamental and culinary value. Species in the genus express highly diverse and chemically unique essential oils that demonstrate intra- and inter-specific patterns that have inspired taxonomic reinterpretation for over a hundred years. Previous studies have conveyed that phenoplastic expression of volatiles creates chemotypes within taxa, adding complexity to chemophenetic exploration. The current study chemically characterised essential oils from 64 highly aromatic specimens, representative of 25 taxa, giving yields as high as >2% g/g. The chemical profiles of essential oils are diverse, but generally include 1,8-cineole and signatory compounds such as sesquiterpene oxides, caryophyllene oxide, kessane and cis-dihydroagarofuran; sesquiterpene alcohols, globulol, epiglobulol, maaliol, prostantherol, spathulenol and ledol; and monoterpene derivatives of common scaffolds, borneol, bornyl acetate, bornanone, linalool and linalyl acetate. As in previous studies, analysis of chemical data confirms that the chemistry strongly agrees with taxonomic classifications. Importantly, as in classical taxonomy, the current chemical study complemented morphological analysis but conveys chemovariation, obscuring the taxonomic agreement. Nevertheless, variation within taxa may be due to environmental factors, meaning that cultivation of species in gardens will create different chemical profiles as compared to those published here.
Phytotoxic Effects and Mechanism of Action of Essential Oils and Terpenoids
Authors: Verdeguer Mercedes , Sánchez-Moreiras Adela M. , Araniti Fabrizio
Published: November 2020

Weeds are one of the major constraints in crop production affecting both yield and quality. The excessive and exclusive use of synthetic herbicides for their management is increasing the development of herbicide-resistant weeds and is provoking risks for the environment and human health. Therefore, the development of new herbicides with multitarget-site activity, new modes of action and low impact on the environment and health are badly needed. The study of plant–plant interactions through the release of secondary metabolites could be a starting point for the identification of new molecules with herbicidal activity. Essential oils (EOs) and their components, mainly terpenoids, as pure natural compounds or in mixtures, because of their structural diversity and strong phytotoxic activity, could be good candidates for the development of new bioherbicides or could serve as a basis for the development of new natural-like low impact synthetic herbicides. EOs and terpenoids have been largely studied for their phytotoxicity and several evidences on their modes of action have been highlighted in the last decades through the use of integrated approaches. The review is focused on the knowledge concerning the phytotoxicity of these molecules, their putative target, as well as their potential mode of action.
Identification of Red Grapevine Cultivars (Vitis vinifera L.) Preserved in Ancient Vineyards in Axarquia (Andalusia, Spain)
Authors: Jiménez-Cantizano Ana , Muñoz-Martín Alejandro , Amores-Arrocha Antonio , Sancho-Galán Pau , Palacios Víctor
Published: November 2020

A prospecting work at the Axarquia region (Malaga, Spain) was carried out in order to identify local red grapevine cultivars preserved in ancient vineyards. A total of 11 accessions were collected in seven different plots from four municipalities and analyzed using 25 microsatellite loci for cultivar identification. The accessions analyzed were identified as eight different genotypes, seven of them corresponding to known cultivars as ‘Cabernet Sauvignon’, ‘Jaen Tinto’, ‘Molinera’, ‘Monastrell’, ‘Muscat of Alexandria’, ‘Parrel’, and ‘Romé’. In addition, one of them is referred to as the new genotype for ‘Cabriel’ cultivar. Additionally, an ampelographic characterization was carried out with 30 International Organisation of Vine and Wine (OIV) descriptors for two consecutive years for the eight accessions identified as local cultivars. This allowed the identification of a somatic variant of the ‘Muscat of Alexandria’ cultivar that affects the color of the berry and another of ‘Romé’ regarding bunch compactness.
Breaking the Dormancy of Snake’s Head Fritillary (Fritillaria meleagris L.) In Vitro Bulbs—Part 2: Effect of GA3 Soaking and Chilling on Sugar Status in Sprouted Bulbs
Authors: Marković Marija , Trifunović Momčilov Milana , Uzelac Branka , Radulović Olga , Milošević Snežana , Jevremović Slađana , Subotić Angelina
Published: November 2020

The bulb is the main propagation organ of snake’s head fritillary (Fritillaria meleagris L.), a horticulturally attractive and rare geophyte plant species. In this study, we investigated the effect of soaking bulbs in GA3 solution (1, 2, and 3 mg L−1) combined with low-temperature treatment (7 °C) on breaking the dormancy of in vitro bulbs. Sugar status (total soluble sugars, glucose, and fructose content) was analyzed in different parts of the sprouted bulbs. The results showed that the soluble sugar concentration was highest in bulbs soaked in GA3. The main sugar in fritillary bulbs was glucose, while fructose content was much lower. Glucose concentration dramatically increased after bulb chilling (7 °C), and its accumulation was predominantly detected in the lower sprout portion during the first weeks of sprouting. Sugar concentration was significantly lower in nonchilled bulbs, which indicates the importance of low temperature in bulb development and sprouting.
Hydroxypropyl Methylcellulose E15: A Hydrophilic Polymer for Fabrication of Orodispersible Film Using Syringe Extrusion 3D Printer
Authors: Panraksa Pattaraporn , Udomsom Suruk , Rachtanapun Pornchai , Chittasupho Chuda , Ruksiriwanich Warintorn , Jantrawut Pensak
Published: November 2020

Extrusion-based 3D printing technology is a relatively new technique that has a potential for fabricating pharmaceutical products in various dosage forms. It offers many advantages over conventional manufacturing methods, including more accurate drug dosing, which is especially important for the drugs that require exact tailoring (e.g., narrow therapeutic index drugs). In this work, we have successfully fabricated phenytoin-loaded orodispersible films (ODFs) through a syringe extrusion 3D printing technique. Two different grades of hydroxypropyl methylcellulose (HPMC E5 and HPMC E15) were used as the film-forming polymers, and glycerin and propylene glycol were used as plasticizers. The 3D-printed ODFs were physicochemically characterized and evaluated for their mechanical properties and in vitro disintegration time. Then, the optimum printed ODFs showing good mechanical properties and the fastest disintegration time were selected to evaluate their drug content and dissolution profiles. The results showed that phenytoin-loaded E15 ODFs demonstrated superior properties when compared to E5 films. It demonstrated a fast disintegration time in less than 5 s and rapidly dissolved and reached up to 80% of drug release within 10 min. In addition, it also exhibited drug content uniformity within United States Pharmacopeia (USP) acceptable range and exhibited good mechanical properties and flexibility with low puncture strength, low Young’s modulus and high elongation, which allows ease of handling and application. Furthermore, the HPMC E15 printing dispersions with suitable concentrations at 10% w/v exhibited a non-Newtonian (shear-thinning) pseudoplastic behavior along with good extrudability characteristics through the extrusion nozzle. Thus, HPMC E15 can be applied as a 3D printing polymer for a syringe extrusion 3D printer.
Poly(ε-Caprolactone)/Poly(Glycerol Sebacate) Composite Nanofibers Incorporating Hydroxyapatite Nanoparticles and Simvastatin for Bone Tissue Regeneration and Drug Delivery Applications
Authors: Rezk Abdelrahman I. , Kim Kyung-Suk , Kim Cheol Sang
Published: November 2020

Herein, we report a drug eluting scaffold composed of a composite nanofibers of poly(ε-caprolactone) (PCL) and poly(glycerol sebacate) (PGS) loaded with Hydroxyapatite nanoparticles (HANPs) and simvastatin (SIM) mimicking the bone extracellular matrix (ECM) to improve bone cell proliferation and regeneration process. Indeed, the addition of PGS results in a slight increase in the average fiber diameter compared to PCL. However, the presence of HANPs in the composite nanofibers induced a greater fiber diameter distribution, without significantly changing the average fiber diameter. The in vitro drug release result revealed that the sustained release of SIM from the composite nanofiber obeying the Korsemeyer–Peppas and Kpocha models revealing a non-Fickian diffusion mechanism and the release mechanism follows diffusion rather than polymer erosion. Biomineralization assessment of the nanofibers was carried out in simulated body fluid (SBF). SEM and EDS analysis confirmed nucleation of the hydroxyapatite layer on the surface of the composite nanofibers mimicking the natural apatite layer. Moreover, in vitro studies revealed that the PCL-PGS-HA displayed better cell proliferation and adhesion compared to the control sample, hence improving the regeneration process. This suggests that the fabricated PCL-PGS-HA could be a promising future scaffold for control drug delivery and bone tissue regeneration application.
Processing Conditions of a Medical Grade Poly(Methyl Methacrylate) with the Arburg Plastic Freeforming Additive Manufacturing Process
Authors: Hentschel Lukas , Kynast Frank , Petersmann Sandra , Holzer Clemens , Gonzalez-Gutierrez Joamin
Published: November 2020

The Arburg Plastic Freeforming process (APF) is a unique additive manufacturing material jetting method. In APF, a thermoplastic material is supplied as pellets, melted and selectively deposited as droplets, enabling the use of commercial materials in their original shape instead of filaments. The medical industry could significantly benefit from the use of additive manufacturing for the onsite fabrication of customized medical aids and therapeutic devices in a fast and economical way. In the medical field, the utilized materials need to be certified for such applications and cannot be altered in any way to make them printable, because modifications annul the certification. Therefore, it is necessary to modify the processing conditions rather than the materials for successful printing. In this research, a medical-grade poly(methyl methacrylate) was analyzed. The deposition parameters were kept constant, while the drop aspect ratio, discharge rate, melt temperatures, and build chamber temperature were varied to obtain specimens with different geometrical accuracy. Once satisfactory geometrical accuracy was obtained, tensile properties of specimens printed individually or in batches of five were tested in two different orientations. It was found that parts printed individually with an XY orientation showed the highest tensile properties; however, there is still room for improvement by optimizing the processing conditions to maximize the mechanical strength of printed specimens.