bluuebunny/crossref_metadata_2025 huggingface dataset:
Grafting with rootstocks promotes phenolic compound accumulation in grape berry skin during development based on integrative multi-omics analysis
Authors: Zhang Fuchun , Zhong Haixia , Zhou Xiaoming , Pan Mingqi , Xu Juan , Liu Mingbo , Wang Min , Liu Guotian , Xu Tengfei , Wang Yuejin , Wu Xinyu , Xu Yan
Published: March 2022

In viticulture, grafting has been practiced widely and influences grape development as well as berry and wine quality. However, there is limited understanding of the effects of rootstocks on grape phenolic compounds, which are located primarily in the berry skin and contribute to certain sensory attributes of wine. In this study, scion–rootstock interactions were investigated at the green-berry stage and the veraison stage when grapevines were hetero-grafted with three commonly used rootstock genotypes (5BB, 101-14MG, and SO4). Physiological investigations showed that hetero-grafts, especially CS/5BB, contained higher concentrations of total proanthocyanidins (PAs) and various PA components in berry skins compared with the auto-grafted grapevines. Further metabolomics analysis identified 105 differentially accumulated flavonoid compounds, the majority of which, including anthocyanins, PAs, and flavonols, were significantly increased in the berry skins of hetero-grafted grapevines compared with auto-grafted controls. In addition, transcriptomic analysis of the same samples identified several thousand differentially expressed genes between hetero-grafted and auto-grafted vines. The three rootstocks not only increased the transcript levels of stilbene, anthocyanin, PA, and flavonol synthesis genes but also affected the expression of numerous transcription factor genes. Taken together, our results suggest that hetero-grafting can promote phenolic compound accumulation in grape berry skin during development. These findings provide new insights for improving the application value of grafting by enhancing the accumulation of nutritious phenolic components in grape.
Leveraging a graft collection to develop metabolome-based trait prediction for the selection of tomato rootstocks with enhanced salt tolerance
Authors: Song Chao , Acuña Tania , Adler-Agmon Michal , Rachmilevitch Shimon , Barak Simon , Fait Aaron
Published: March 2022

Grafting has been demonstrated to significantly enhance the salt tolerance of crops. However, breeding efforts to develop enhanced graft combinations are hindered by knowledge-gaps as to how rootstocks mediate scion-response to salt stress. We grafted the scion of cultivated M82 onto rootstocks of 254 tomato accessions and explored the morphological and metabolic responses of grafts under saline conditions (EC = 20 dS m−1) as compared to self-grafted M82 (SG-M82). Correlation analysis and Least Absolute Shrinkage and Selection Operator were performed to address the association between morphological diversification and metabolic perturbation. We demonstrate that grafting the same variety onto different rootstocks resulted in scion phenotypic heterogeneity and emphasized the productivity efficiency of M82 irrespective of the rootstock. Spectrophotometric analysis to test lipid oxidation showed largest variability of malondialdehyde (MDA) equivalents across the population, while the least responsive trait was the ratio of fruit fresh weight to total fresh weight (FFW/TFW). Generally, grafts showed greater values for the traits measured than SG-M82, except for branch number and wild race-originated rootstocks; the latter were associated with smaller scion growth parameters. Highly responsive and correlated metabolites were identified across the graft collection including malate, citrate, and aspartate, and their variance was partly related to rootstock origin. A group of six metabolites that consistently characterized exceptional graft response was observed, consisting of sorbose, galactose, sucrose, fructose, myo-inositol, and proline. The correlation analysis and predictive modelling, integrating phenotype- and leaf metabolite data, suggest a potential predictive relation between a set of leaf metabolites and yield-related traits.
Characterization and functional validation of β-carotene hydroxylase AcBCH genes in Actinidia chinensis
Authors: Xia Hui , Zhou Yuanjie , Lin Zhiyi , Guo Yuqi , Liu Xinling , Wang Tong , Wang Jin , Deng Honghong , Lin Lijin , Deng Qunxian , Lv Xiulan , Xu Kunfu , Liang Dong
Published: March 2022

Carotenoids are the pigment substances of yellow-fleshed kiwifruit, and among them β-cryptoxanthin has only been detected in the brighter yellow-fleshed variety ‘Jinshi 1’. β-Carotene hydroxylase (BCH) catalyzes the formation of β-cryptoxanthin and zeaxanthin, but its molecular characteristics and functions have not been fully explained. Here we isolated two β-carotene hydroxylase genes, AcBCH1 and AcBCH2 from kiwifruit (Actinidia chinensis), and their relative expression levels exhibited a close correlation with the content of β-cryptoxanthin. AcBCH1 catalyzed the formation of β-cryptoxanthin when transformed into β-carotene-accumulating yeast cells. Moreover, silenced expression of AcBCH1 in kiwifruit caused decreases in the contents of zeaxanthin, lutein, and β-cryptoxanthin, and an increase in β-carotene content. The content of β-carotene decreased significantly after the AcBCH1/2 genes were overexpressed in tomato. The content of zeaxanthin increased and β-carotene decreased in transgenic kiwifruit seedlings. The results will enrich our knowledge of the molecular mechanisms of carotenoid biosynthesis in kiwifruit.
An efficient CRISPR/Cas9 system for simultaneous editing two target sites in Fortunella hindsii
Authors: Xu Yanhui , Zhang Li , Lu Liqing , Liu Jihong , Yi Hualin , Wu Juxun
Published: March 2022

The CRISPR/Cas9 system is a revolutionary genome editing technique and has been widely used in numerous plants. For plants (e.g. citrus) with very low transformation efficiency, how to optimize gene editing efficiency and induce large-fragment deletion has been the focus of research. Here, we report that CRISPR/Cas9 induces efficient deletion of 16–673 bp fragments in the genome of Fortunella hindsii. The ability of two binary vectors, pK7WG2D and pMDC32, to introduce specific mutations into the genome of F. hindsii was evaluated. Double single guide RNAs (sgRNAs) were designed to achieve precise editing of two sites of a gene and deletion of fragments between the two sites. The construction of vectors based on Golden Gate assembly and Gateway recombination cloning is simple and efficient. pK7WG2D is more suitable for F. hindsii genome editing than the pMDC32 vector. Editing efficiency using the pK7WG2D vector reached 66.7%. Allele mutation frequency was 7.14–100%. Plants with 100% allele mutations accounted for 39.4% (13 100% allele mutation plants/33 mutants). The proportion of mutant plants with fragment deletion induced by this editing system was as high as 52.6% (10 fragment-deletion mutants/19 FhNZZ mutants). Altogether, these data suggest that our CRISPR/Cas9 platform is capable of targeted genome editing in citrus and has broad application in research on the citrus functional genome and citrus molecular breeding.
Apple, Test of Insecticides, 1976
Authors: Asquith Dean , Hull Larry A. , Travis James W. , Mowery Paul D.
Published: March 2022

Experimental sprays were applied to run-off to single-tree plots in a complete randomized block design with 4 replicates of Golden Delicious except GCP-5126 which was applied to 4 York Imperial trees, a better host of the white apple leafhopper. Treated single-frees were separated by others not sprayed with insecticides. Experimental sprays were applied with a John Bean sprayer, 35 gpm pump, equipped with a spray mast carrying 7 spray guns arranged to wet the uniformly trimmed trees. Spray dates for the test insecticides were: Apr 27, May 7, Aug 3 and Aug 18 only for GCP-5126. Guthion was applied to these same trees on May 25, June 8 and June 23. Other test insecticides were applied on May 6 and 7, May 25, June 8, June 23, Aug 3 and 4, and Aug 18 and 19. The split dates indicate interruption of spraying by weather. Both dosages of Sumithion were discontinued after June 23. During May, general sprays involving Cyprex, Polyram, sulfur, and calcium chloride were applied as 6X concentrates with an airblast sprayer to the whole experimental block. From June 1 to July 6, the general sprays involved captan, sulfur, and calcium chloride. Late season general sprays were of captan and zineb. Average temperatures weTe: May 57.74° F, June 71.30° F, July 70.09° F, August 67.92° F, and September 62.78° F. Rainfall in inches averaged: May 5.68, June 2.63, July 4.86, August 2.62, September 4.49. Effectiveness of the test chemicals on the European red mite and the twospotted spider mite was evaluated by counting the mites several times during the season on samples of 20 leaves/tree, 80 leaves/treatment. The effect of sprays on the predator S. punctum was evaluated by 3-min counts of adults and larvae around the periphery of the test trees. Effectiveness of chemicals on fruit feeders was assessed by scoring for injury all drops after July 1 and two picked samples, Aug 16 and 30. Apple samples averaged 121 fruits/replicate, 484/treatment002E
Nitrites and nitrates from food additives and natural sources and cancer risk: results from the NutriNet-Santé cohort
Authors: Chazelas Eloi , Pierre Fabrice , Druesne-Pecollo Nathalie , Esseddik Younes , Szabo de Edelenyi Fabien , Agaesse Cédric , De Sa Alexandre , Lutchia Rebecca , Gigandet Stéphane , Srour Bernard , Debras Charlotte , Huybrechts Inge , Julia Chantal , Kesse-Guyot Emmanuelle , Allès Benjamin , Galan Pilar , Hercberg Serge , Deschasaux-Tanguy Mélanie , Touvier Mathilde
Published: March 2022

Background

Nitrates and nitrites occur naturally in water and soil. They are also used as food additives (preservatives) in processed meats. They could play a role in the carcinogenicity of processed meat. The objective was to investigate the relationship between nitrate and nitrite intakes (natural food, water and food additive sources) and cancer risk in a large prospective cohort with detailed dietary assessment.

Methods

Overall, 101    056 adults from the French NutriNet-Santé cohort (2009–ongoing, median follow-up 6.7 years) were included. Nitrites/nitrates exposure was evaluated using repeated 24-h dietary records, linked to a comprehensive composition database and accounting for commercial names/brands of industrial products. Associations with cancer risk were assessed using multi-adjusted Cox hazard models.

Results

In total, 3311 incident cancer cases were diagnosed. Compared with non-consumers, high consumers of food additive nitrates had higher breast cancer risk [hazard ratio (HR) = 1.24 (95% CI 1.03–1.48), P = 0.02], more specifically for potassium nitrate. High consumers of food additive nitrites had higher prostate cancer risk [HR = 1.58 (1.14–2.18), P = 0.008], specifically for sodium nitrite. Although similar HRs were observed for colorectal cancer for additive nitrites [HR = 1.22 (0.85–1.75)] and nitrates [HR = 1.26 (0.90–1.76)], no association was detected, maybe due to limited statistical power for this cancer location. No association was observed for natural sources.

Conclusion

Food additive nitrates and nitrites were positively associated with breast and prostate cancer risks, respectively. Although these results need confirmation in other large-scale prospective studies, they provide new insights in a context of lively debate around the ban of these additives from the food industry.
Persistent Antibody Responses Up to 18 Months After Mild Severe Acute Respiratory Syndrome Coronavirus 2 Infection
Authors: Choe Pyoeng Gyun , Hong Jisu , Park Jiyoung , Chang Euijin , Kang Chang Kyung , Kim Nam Joong , Lee Chang Han , Park Wan Beom , Oh Myoung don
Published: March 2022

Background

Humoral immunity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may wane rapidly in persons recovered from mild coronavirus disease 2019 (COVID-19), but little is known about the longevity.

Methods

Serum samples were obtained 8, 12, and 18 months after infection from 20 patients with mild COVID-19. The binding activities of serum antibodies (immunoglobulin [Ig]A, IgG, and IgM) against SARS-CoV-2 antigens of the Wuhan-1 reference strain (wild-type) and the B.1.1.7, P.1, B.1.167.2, and B.1.1.529 variants were measured by enzyme-linked immunosorbent assays. Neutralizing antibody titers were measured using a cytopathic effect-based live virus neutralization assay.

Results

Serum IgA and IgG antibodies against spike or receptor-binding domain (RBD) protein of wild-type SARS-CoV-2 were detected for up to 18 months, and neutralizing antibodies persisted for 8 to 18 months after infection. However, any significant antibody responses against RBD proteins of SARS-CoV-2 variants were not observed, and median neutralizing antibody titers against the Delta variant at 8, 12, and 18 months were 8- to 11-fold lower than against wild-type viruses (P<.001).

Conclusions

Humoral immunity persisted for up to 18 months after SARS-CoV-2 infection in patients with mild COVID-19. However, humoral immune activity against more recently circulating variants was reduced in this population.
From random to predictive: a context-specific interaction framework improves selection of drug protein–protein interactions for unknown drug pathways
Authors: Wilson Jennifer L , Gravina Alessio , Grimes Kevin
Published: March 2022

With high drug attrition, protein–protein interaction (PPI) network models are attractive as efficient methods for predicting drug outcomes by analyzing proteins downstream of drug targets. Unfortunately, these methods tend to overpredict associations and they have low precision and prediction performance; performance is often no better than random (AUROC ~0.5). Typically, PPI models identify ranked phenotypes associated with downstream proteins, yet methods differ in prioritization of downstream proteins. Most methods apply global approaches for assessing all phenotypes. We hypothesized that a per-phenotype analysis could improve prediction performance. We compared two global approaches—statistical and distance-based—and our novel per-phenotype approach, ‘context-specific interaction’ (CSI) analysis, on severe side effect prediction. We used a novel dataset of adverse events (or designated medical events, DMEs) and discovered that CSI had a 50% improvement over global approaches (AUROC 0.77 compared to 0.51), and a 76–95% improvement in average precision (0.499 compared to 0.284, 0.256). Our results provide a quantitative rationale for considering downstream proteins on a per-phenotype basis when using PPI network methods to predict drug phenotypes.
Definitive outcomes in patients with rifampicin-resistant tuberculosis treated in Niger from 2012 to 2019: A retrospective cohort study
Authors: Souleymane Mahamadou Bassirou , Decroo Tom , Mamadou Saïdou , Soumana Alphazazi , Lawan Ibrahim Mamane , Gagara-Issoufou Assiatou , Adehossi Eric , Ortuño-Gutiérrez Nimer , Lynen Lutgarde , Rigouts Leen , de Jong Bouke Catherine , Van Deun Armand , Piubello Alberto
Published: March 2022

Background

Outcomes of retreatment for rifampicin-resistant tuberculosis (RR-TB) are rarely reported. We report ‘definitive outcomes’ after a cascade approach to RR-TB treatment. After a bacteriologically adverse outcome for the 9-months fluoroquinolone-based Short Treatment Regimen (STR), patients were retreated with a bedaquiline-based regimen (BDQ-regimen).

Methods

A Retrospective cohort study of RR-TB patients treated with the STR during 2012–2019 and retreated with a BDQ-regimen in case of failure or relapse was conducted. Definitive relapse-free cure took into account BDQ-regimen outcomes.

Results

Of 367 patients treated with the STR, 20 (5.4%) experienced failure or relapse. Out of these 20 patients, 14 started a BDQ-regimen, of whom none experienced failure or relapse. Definitive end of treatment outcomes of STR after revising with third-line BDQ-regimen outcomes, 84.7% (311/367) were cured relapse-free, 10.6% (39/367) died during treatment and 3.0% (11/367) were lost to follow-up during treatment with either the STR or BDQ-regimen. Six patients (1.6%; 6/367) with STR failure/relapse died before starting a BDQ-regimen. No patient had definitive treatment failure or relapse and remained without treatment.

Conclusions

If fluoroquinolone resistance is excluded or rare, it is beneficial to use fluoroquinolone as the core drug for a first RR-TB treatment regimen and to safeguard bedaquiline for those in need of retreatment.
Ownership-neutral or ownership-blind? The case of Polish state-owned enterprises in EU merger control
Authors: Svetlicinii Alexandr
Published: March 2022

The article discusses the challenges associated with the assessment of economic concentrations involving state-owned enterprises (SOEs) under the European Union (EU) merger control. It reveals inconsistencies in ascertaining the exercise of and the (anti)competitive effects stemming from the state control over the SOEs caused by the strategic use of the ‘single economic unit’ concept in cases involving both European and non-European SOEs. Using the example of Poland and its economic statecraft, the article demonstrates how the use of various ownership-based and regulatory mechanisms employed by the State allows it to preserve control over strategic industries and enterprises. The study suggests that insufficient attention to the state ownership and state control in the EU merger control may create a risk of anti-competitive market distortions caused by the SOE-led industrial policies of the Member States to the detriment of the functioning of the internal market.
Developing an algorithm across integrated healthcare systems to identify a history of cancer using electronic medical records
Authors: Gander Jennifer C , Maiyani Mahesh , White Larissa L , Sterrett Andrew T , Güney Brianna , Pawloski Pamala A , DeFor Teri , Olsen YuanYuan , Rybicki Benjamin A , Neslund-Dudas Christine , Sheth Darsheen , Krajenta Richard , Purushothaman Devaki , Honda Stacey , Yonehara Cyndee , Goddard Katrina A B , Prado Yolanda K , Ahsan Habibul , Kibriya Muhammad G , Aschebrook-Kilfoy Briseis , Chan Chun-Hung , Hague Sarah , Clarke Christina L , Thompson Brooke , Sawyer Jennifer , Gaudet Mia M , Feigelson Heather Spencer
Published: March 2022

Objective

Tumor registries in integrated healthcare systems (IHCS) have high precision for identifying incident cancer but often miss recently diagnosed cancers or those diagnosed outside of the IHCS. We developed an algorithm using the electronic medical record (EMR) to identify people with a history of cancer not captured in the tumor registry to identify adults, aged 40–65 years, with no history of cancer.

Materials and Methods

The algorithm was developed at Kaiser Permanente Colorado, and then applied to 7 other IHCS. We included tumor registry data, diagnosis and procedure codes, chemotherapy files, oncology encounters, and revenue data to develop the algorithm. Each IHCS adapted the algorithm to their EMR data and calculated sensitivity and specificity to evaluate the algorithm’s performance after iterative chart review.

Results

We included data from over 1.26 million eligible people across 8 IHCS; 55 601 (4.4%) were in a tumor registry, and 44848 (3.5%) had a reported cancer not captured in a registry. The common attributes of the final algorithm at each site were diagnosis and procedure codes. The sensitivity of the algorithm at each IHCS was 90.65%–100%, and the specificity was 87.91%–100%.

Discussion

Relying only on tumor registry data would miss nearly half of the identified cancers. Our algorithm was robust and required only minor modifications to adapt to other EMR systems.

Conclusion

This algorithm can identify cancer cases regardless of when the diagnosis occurred and may be useful for a variety of research applications or quality improvement projects around cancer care.
Calcium-sensing receptor is not expressed in the absorptive enterocytes of weaned piglets
Authors: Zhao Xiaoya , Hui Qianru , Azevedo Paula , Nyachoti Charles Martin , O Karmin , Yang Chengbo
Published: March 2022

The calcium-sensing receptor (CaSR) is a kokumi receptor that plays an essential role in nutrient sensing and animal physiology, growth, and development. Pig CaSR (pCaSR) was identified and characterized in the intestine. However, further research is still needed to confirm the expression of CaSR in the epithelial cells isolated from weaned piglets. In this study, primary enterocytes were isolated and characterized from the ileum of weaned piglets by the Weiser distended intestinal sac technique and fluorescence-activated cell sorting (FACS) based on sucrase-isomaltase (SI) as an enterocyte-specific marker. The expression of CaSR was investigated in both primary enterocytes and the intestinal porcine enterocyte cell line-j2 (IPEC-J2) by droplet digital polymerase chain reaction (ddPCR), immunofluorescence staining, and Western blotting. Results demonstrated that porcine enterocytes could be obtained using FACS with the SI as the enterocyte-specific marker and that pCaSR is not expressed in both porcine ileal enterocytes and IPEC-J2 cells, which specifically identified the expression of pCaSR in ileal enterocytes with sensitive and specific approaches.
Designing an Intervention Trial of Human-Tick Encounters and Tick-Borne Diseases in Residential Settings Using 4-Poster Devices to Control Ixodes scapularis (Acari: Ixodidae): Challenges for Site Selection and Device Placement
Authors: Connally Neeta P , Rowe Adam , Kaufman Alison , Meek James I , Niesobecki Sara A , Hansen Amberjean P , White Jennifer , Nawrocki Courtney , Foster Erik , Hinckley Alison F , Eisen Lars
Published: March 2022

Blacklegged ticks, Ixodes scapularis Say, transmit Lyme disease spirochetes and other human pathogens in the eastern United States. White-tailed deer (Odocoileus virginianus) are key reproductive hosts for I. scapularis adults, and therefore control methods targeting deer have the potential for landscape-wide tick suppression. A topical acaricide product, containing 10% permethrin, is self-applied by deer to kill parasitizing ticks when they visit 4-Poster Tick Control Deer Feeders (hereafter, 4-Posters) Previous 4-Poster intervention studies, including in residential settings, demonstrated suppression of I. scapularis populations but did not include human-based outcomes. To prepare for a proposed 4-Poster intervention trial in residential areas of Connecticut and New York that would include human-tick encounters and tick-borne diseases as outcomes, we sought to identify areas (study clusters) in the 80–100 ha size range and specific locations within these areas where 4-Poster devices could be deployed at adequate density (1 device per 20–25 ha) and in accordance with regulatory requirements. Geographic Information System-based data were used to identify prospective study clusters, based on minimum thresholds for Lyme disease incidence, population density, and forest cover. Ground truthing of potential 4-Poster placement locations was done to confirm the suitability of selected clusters. Based on these efforts, we failed to identify more than a few residential areas fulfilling all criteria for a treatment cluster. We, therefore, reconsidered pursuing the intervention trial, which required inclusion of >30 treatment clusters to achieve adequate statistical power. The 4-Poster methodology may be more readily evaluated in natural or public areas than in residential settings in NY or CT.
Mapping Exposure Diversity: The Divergent Effects of Algorithmic Curation on News Consumption
Authors: Jürgens Pascal , Stark Birgit
Published: March 2022

Diversity is a crucial precondition for a democratic public discourse. In today’s high-choice media environments, exposure to diverse news is largely determined by individuals’ personal selection. Yet these decisions are increasingly shaped by online platforms, whose curation mechanisms may serve to expand or contract the diversity of encountered content. In a major extension of existing research, we show that positive short-term effects of platforms mask detrimental long-term effects. Drawing on a four-month tracking dataset and a comprehensive content analysis covering the online news consumption of over 10,000 German citizens, we demonstrate that even though short-term usage of platforms uniformly increases exposure diversity, long-term reliance can lead to decreases. In addition, platforms vary in their influences: News aggregators are beneficial to exposure diversity, while Twitter and search engines have a limiting effect; Facebook offers no significant influence.
External jugular vein spontaneous aneurysm: a case report
Authors: El Youbi Samir , Naouli Hamza , Jiber Hamid , Bouarhroum Abdellatif
Published: March 2022

Venous aneurysm of external jugular vein is very rare clinical entity. Often asymptomatic, the diagnosis may be suggested by clinical features and is usually confirmed by imaging. Surgical excision is indicated in symptomatic aneurysms and for esthetic reasons, other treatments such as endovascular treatment are being evaluated. We report a case of a 27-year-old woman with a saccular aneurysm of the right external jugular vein diagnosed by computerized tomogram angiography. The patient received successful surgical treatment.
PHB3 regulates lateral root primordia formation via NO-mediated degradation of AUXIN/INDOLE-3-ACETIC ACID proteins
Authors: Li Shuna , Li Qingqing , Tian Xiao , Mu Lijun , Ji Meiling , Wang Xiaoping , Li Na , Liu Fei , Shu Jing , Crawford Nigel M , Wang Yong
Published: March 2022

We have previously shown that Arabidopsis thaliana Prohibitin 3 (PHB3) controls auxin-stimulated lateral root (LR) formation; however, the underlying molecular mechanism is unknown. Here, we demonstrate that PHB3 regulates lateral root (LR) development mainly through influencing lateral root primordia (LRP) initiation, via affecting nitric oxide (NO) accumulation. The reduced LRP in phb3 mutant was largely rescued by treatment with a NO donor. The decreased NO accumulation in phb3 caused a lower expression of GATA TRANSCRIPTION FACTOR 23 (GATA23) and LATERAL ORGAN BOUNDARIES DOMAIN 16 (LBD16) through inhibiting the degradation of INDOLE-3-ACETIC ACID INDUCIBLE 14/28 (IAA14/28). Overexpression of either GATA23 or LBD16 in phb3 mutant background recovered the reduced density of LRP. These results indicate that PHB3 regulates LRP initiation via NO-mediated auxin signalling, by modulating the degradation of IAA14/28.
Underlying mechanism of accelerated cell death and multiple disease resistance in a maizelethal leaf spot 1allele
Authors: Li Jiankun , Chen Mengyao , Fan Tianyuan , Mu Xiaohuan , Gao Jie , Wang Ying , Jing Teng , Shi Cuilan , Niu Hongbin , Zhen Sihan , Fu Junjie , Zheng Jun , Wang Guoying , Tang Jihua , Gou Mingyue
Published: March 2022

Multiple disease resistance (MDR) in maize has attracted increasing attention. However, the interplay between cell death and metabolite changes and their contributions to MDR remains elusive in maize. In this study, we identified a mutant named as lesion mimic 30 (les30) that showed ‘suicidal’ lesion formation in the absence of disease and had enhanced resistance to the fungal pathogen Curvularia lunata. Using map-based cloning, we identified the causal gene encoding pheophorbide a oxidase (PAO), which is known to be involved in chlorophyll degradation and MDR, and is encoded by LETHAL LEAF SPOT1 (LLS1). LLS1 was found to be induced by both biotic and abiotic stresses. Transcriptomics analysis showed that genes involved in defense responses and secondary metabolite biosynthesis were mildly activated in leaves of the les30 mutant without lesions, whilst they were strongly activated in leaves with lesions. In addition, in les30 leaves with lesions, there was overaccumulation of defense-associated phytohormones including jasmonic acid and salicylic acid, and of phytoalexins including phenylpropanoids, lignin, and flavonoids, suggesting that their biosynthesis was activated in a lesion-dependent manner. Taken together, our study implies the existence of an interactive amplification loop of interrupted chlorophyll degradation, cell death, expression of defense-related genes, and metabolite changes that results in suicidal lesion formation and MDR, and this has the potential to be exploited by genetic manipulation to improve maize disease resistance.
Combining analyses of metabolite profiles and phosphorus fractions to explore high phosphorus utilization efficiency in maize
Authors: Han Yang , Hong Wanting , Xiong Chuanyong , Lambers Hans , Sun Yan , Xu Zikai , Schulze Waltraud X , Cheng Lingyun
Published: March 2022

Phosphorus (P) limitation is a significant factor restricting crop production in agricultural systems, and enhancing the internal P utilization efficiency (PUE) of crops plays an important role in ensuring sustainable P use in agriculture. To better understand how P is remobilized to affect crop growth, we first screened P-efficient (B73 and GEMS50) and P-inefficient (Liao5114) maize genotypes at the same shoot P content, and then analyzed P pools and performed non-targeted metabolomic analyses to explore changes in cellular P fractions and metabolites in maize genotypes with contrasting PUE. We show that lipid P and nucleic acid P concentrations were significantly lower in lower leaves of P-efficient genotypes, and these P pools were remobilized to a major extent in P-efficient genotypes. Broad metabolic alterations were evident in leaves of P-efficient maize genotypes, particularly affecting products of phospholipid turnover and phosphorylated compounds, and the shikimate biosynthesis pathway. Taken together, our results suggest that P-efficient genotypes have a high capacity to remobilize lipid P and nucleic acid P and promote the shikimate pathway towards efficient P utilization in maize.
Sculpting the circumbinary planet size distribution through resonant interactions with companion planets
Authors: Fitzmaurice Evan , Martin David V , Fabrycky Daniel C
Published: March 2022

Resonant locking of two planets is an expected outcome of convergent disc migration. The planets subsequently migrate together as a resonant pair. In the context of circumbinary planets, the disc is truncated internally by the binary. If there were only a single planet, then this inner disc edge would provide a natural parking location. However, for two planets migrating together in resonance there will be a tension between the inner planet stopping at the disc edge and the outer planet continuing to be torqued inwards. In this paper, we study this effect, showing that the outcome is a function of the planet–planet mass ratio. Smaller outer planets tend to be parked in a stable exterior 2:1 or 3:2 resonance with the inner planet, which remains near the disc edge. Equal or larger mass outer planets tend to push the inner planet past the disc edge and too close to the binary, causing it to be ejected or sometimes flipped to an exterior orbit. Our simulations show that this process may explain an observed dearth of small (<3 R⊕) circumbinary planets, since small planets are frequently ejected or left on long-period orbits, for which transit detection is less likely. This may also be an effective mechanism for producing free-floating planets and interstellar interlopers like ‘Oumuamua.
Galaxy–galaxy strong lens perturbations: line-of-sight haloes versus lens subhaloes
Authors: He Qiuhan , Li Ran , Frenk Carlos S , Nightingale James , Cole Shaun , Amorisco Nicola C , Massey Richard , Robertson Andrew , Etherington Amy , Amvrosiadis Aristeidis , Cao Xiaoyue
Published: March 2022

We rederive the number density of intervening line-of-sight haloes relative to lens subhaloes in galaxy-galaxy strong lensing observations, where these perturbers can generate detectable image fluctuations. Previous studies have calculated the detection limit of a line-of-sight small-mass dark halo by comparing the lensing deflection angles it would cause, to those caused by a subhalo within the lens. However, this overly simplifies the difference in observational consequences between a subhalo and a line-of-sight halo. Furthermore, it does not take into account degeneracies between an extra subhalo and the uncertain properties of the main lens. More in keeping with analyses of real-world observations, we regard a line-of-sight halo as detectable only if adding it to a smooth model generates a statistically significant improvement in the reconstructed image. We find that the number density of detectable line-of-sight perturbers has been overestimated by as much as a factor of two in the previous literature. For typical lensing geometries and configurations, very deep imaging is sensitive to twice as many line-of-sight perturbers as subhaloes, but moderate depth imaging is sensitive to only slightly more line-of-sight perturbers than subhaloes.
Discovery of a quasar with double-peaked broad balmer emission lines
Authors: Terwel Jacco H , Jonker Peter G
Published: March 2022

Most massive galaxies contain a supermassive black hole (SMBH) at their centre. When galaxies merge, their SMBHs sink to the centre of the new galaxy, where they are thought to eventually merge. During this process, an SMBH binary is formed. The presence of two sets of broad emission lines in the optical spectrum of an active galactic nucleus (AGN) has been interpreted as evidence for two broad-line regions (BLRs), one surrounding each SMBH in a binary. We modelled the broad Balmer emission lines in the SDSS spectra of 373 extreme variability AGNs using one broad and several narrow Gaussian components. We report on the discovery of SDSS J021647.53 − 011341.5 (hereafter J0216) as a double-peaked broad emission line source. Among the 373 AGNs, there were five sources that are known as double-peaked emission line sources. Three of these have been reported as candidate SMBH binaries in previous studies. We present all six objects and their double-peaked broad Balmer emission lines, and discuss the implications for a tidal disruption event (TDE) interpretation of the extreme variability, assuming the double-peaked sources are SMBH binaries.
Tempo of Degeneration Across Independently Evolved Nonrecombining Regions
Authors: Carpentier Fantin , Rodríguez de la Vega Ricardo C. , Jay Paul , Duhamel Marine , Shykoff Jacqui A. , Perlin Michael H. , Wallen R. Margaret , Hood Michael E. , Giraud Tatiana
Published: March 2022

Recombination is beneficial over the long term, allowing more effective selection. Despite long-term advantages of recombination, local recombination suppression can evolve and lead to genomic degeneration, in particular on sex chromosomes. Here, we investigated the tempo of degeneration in nonrecombining regions, that is, the function curve for the accumulation of deleterious mutations over time, leveraging on 22 independent events of recombination suppression identified on mating-type chromosomes of anther-smut fungi, including newly identified ones. Using previously available and newly generated high-quality genome assemblies of alternative mating types of 13 Microbotryum species, we estimated degeneration levels in terms of accumulation of nonoptimal codons and nonsynonymous substitutions in nonrecombining regions. We found a reduced frequency of optimal codons in the nonrecombining regions compared with autosomes, that was not due to less frequent GC-biased gene conversion or lower ancestral expression levels compared with recombining regions. The frequency of optimal codons rapidly decreased following recombination suppression and reached an asymptote after ca. 3 Ma. The strength of purifying selection remained virtually constant at dN/dS = 0.55, that is, at an intermediate level between purifying selection and neutral evolution. Accordingly, nonsynonymous differences between mating-type chromosomes increased linearly with stratum age, at a rate of 0.015 per My. We thus develop a method for disentangling effects of reduced selection efficacy from GC-biased gene conversion in the evolution of codon usage and we quantify the tempo of degeneration in nonrecombining regions, which is important for our knowledge on genomic evolution and on the maintenance of regions without recombination.
Telomerase RNA TERC and the PI3K-AKT pathway form a positive feedback loop to regulate cell proliferation independent of telomerase activity
Authors: Wu Shu , Ge Yuanlong , Lin Kaixuan , Liu Qianqian , Zhou Haoxian , Hu Qian , Zhao Yong , He Weifeng , Ju Zhenyu
Published: March 2022

The core catalytic unit of telomerase comprises telomerase reverse transcriptase (TERT) and telomerase RNA (TERC). Unlike TERT, which is predominantly expressed in cancer and stem cells, TERC is ubiquitously expressed in normal somatic cells without telomerase activity. However, the functions of TERC in these telomerase-negative cells remain elusive. Here, we reported positive feedback regulation between TERC and the PI3K-AKT pathway that controlled cell proliferation independent of telomerase activity in human fibroblasts. Mechanistically, we revealed that TERC activated the transcription of target genes from the PI3K-AKT pathway, such as PDPK1, by targeting their promoters. Overexpression of PDPK1 partially rescued the deficiency of AKT activation caused by TERC depletion. Furthermore, we found that FOXO1, a transcription factor negatively regulated by the PI3K-AKT pathway, bound to TERC promoter and suppressed its expression. Intriguingly, TERC-induced activation of the PI3K-AKT pathway also played a critical role in the proliferation of activated CD4+ T cells. Collectively, our findings identify a novel function of TERC that regulates the PI3K-AKT pathway via positive feedback to elevate cell proliferation independent of telomerase activity and provide a potential strategy to promote CD4+ T cells expansion that is responsible for enhancing adaptive immune reactions to defend against pathogens and tumor cells.
The Role of Nicotine and Flavor in the Abuse Potential and Appeal of Electronic Cigarettes for Adult Current and Former Cigarette and Electronic Cigarette Users: A Systematic Review
Authors: Gades Mari S , Alcheva Aleksandra , Riegelman Amy L , Hatsukami Dorothy K
Published: March 2022

Introduction

Many adult cigarette smokers use electronic cigarettes (e-cigarettes) to cut down on or quit smoking cigarettes. E-cigarettes with higher abuse potential and appeal might facilitate complete switching. E-liquid nicotine concentration and flavor are two of the characteristics that may affect the abuse potential and appeal of e-cigarettes. The objective of this systematic review was to compile results from survey, animal, human laboratory, and clinical studies to understand the possible effects of nicotine concentration and flavor on abuse potential and appeal of e-cigarettes in adult current and former cigarette and e-cigarette users.

Aims and Methods

A comprehensive literature search was conducted in Ovid Medline and PsycINFO followed by citation tracking in Web of Science Core Collection. Peer-reviewed studies published in English between 2007 and August 2020 were selected that analyzed differences between e-liquid nicotine concentration and/or flavors, had outcome measures related to abuse potential and/or appeal, and included adult humans (18+) or animals. A total of 1624 studies were identified and screened. A qualitative synthesis of results was performed.

Results

Results from 104 studies included in this review suggest that higher nicotine concentration and access to a variety of flavors are likely to be associated with higher abuse potential and appeal of e-cigarettes for adult current and former cigarette and e-cigarette users.

Conclusions

Higher nicotine concentrations and the availability of a variety of flavors in e-cigarettes might facilitate complete substitution for cigarettes. Future e-cigarette regulations should take into account their impact on smokers, for whom e-cigarettes may be a cessation tool or reduced-harm alternative.

Implications

E-cigarettes may provide a reduced-harm alternative to cigarettes for smokers unwilling/unable to quit or serve as a path for quitting all nicotine products. Higher nicotine concentrations and flavor variety are associated with higher abuse potential and appeal of e-cigarettes. Higher abuse potential and appeal products may help facilitate complete switching from cigarettes to e-cigarettes. Regulation of nicotine concentration and flavors aimed at decreasing naïve uptake may inadvertently decrease uptake and complete switching among smokers, reducing the harm reduction potential of e-cigarettes. Evidence-based effects of regulating nicotine concentration and flavors must be considered for the population as a whole, including smokers.
Unexpected case of accelerated silicosis in a female quarry worker
Authors: Leong Tracy L , Wimaleswaran Hari , Williams David S , Goh Nicole S , Hoy Ryan F
Published: March 2022

Silicosis is a progressive and irreversible fibrotic occupational lung disease caused by inhalation of respirable crystalline silica (RCS). Recently, outbreaks have been reported in industries involving direct work with high silica-containing materials, such as artificial stone. Here, we describe an unexpected diagnosis made in an asymptomatic 33-year-old female worker employed for 4 years at a quarry for rhyodacite and rhyolite which contain 70% silicon dioxide. Chest computed tomography demonstrated small nodules in the upper lobes and larger ill-defined areas of opacity. Bronchoalveolar lavage revealed fine birefringent material within the cytoplasm of alveolar macrophages, representing silica. Transbronchial biopsies of lung parenchyma and endobronchial ultrasound-guided transbronchial needle aspiration of mediastinal lymph nodes did not reveal features of sarcoidosis, tuberculosis, or malignancy. As such, a diagnosis of accelerated silicosis was confirmed and represents the first reported case in a female worker at a rhyodacite and rhyolite quarry.
Occupational contact urticaria to cannabis sativa
Authors: Yeo L , Debusscher C , White J M L
Published: March 2022

Cannabis allergy is not commonly reported, perhaps due to the legal status of cannabis use and the difficulties of obtaining permission to test it. We report 3 cases of work-related cannabis allergy with features suggestive of a dermatitis, rather than a contact urticaria. Only prick tests were able to confirm the diagnosis. Identification of the cause of the rash was essential to direct work re-deployment.
Innovation in low-energy demand and its implications for policy
Authors: Nemet Gregory , Greene Jenna
Published: March 2022

Scenarios featuring low-energy demand (LED) have the potential to meet climate stabilization targets while also pursuing inclusive well-being and multiple Sustainable Development Goals. Recent papers have assembled detailed bottom-up estimates to inform integrated assessment modeling and show that LED outcomes are feasible and have beneficial effects across multiple goals. But realizing the full potential in LED depends on innovation—i.e. improvement in LED technology and widespread adoption of both LED technology and behavior—as well as policies supporting innovation. We review the literature to better understand the role of technological innovation in enabling LED scenarios and how policy interventions can stimulate those innovations. We structure our review using a policy analysis framework that includes specifying multiple LED policy goals, describing the distinct characteristics of LED technology to understand policy needs. The distinct characteristics of LED innovation include multiple attributes and new services; many heterogeneous adopters; small granular scale, many iterations; local system integration; and rebound effects, among others. We also consider five important drivers of change in LED innovation: higher living standards and preferences for clean environments, urbanization, digitalization, demand for novel services and the emergence of prosumers. The analysis in this review of the literature leads to nine LED policy design guidelines.
Microzooplankton grazing and community composition in a high-productivity marine ecosystem
Authors: Wickham Stephen A , Wenta Philipp , Sinner Anita , Weiss Richard
Published: March 2022

Eastern Boundary Upwelling Ecosystems (EBUE’s) are highly productive, and due to their extensive fisheries, of major economic importance. Compared to oligotrophic systems, however, relatively little is known about the fate of primary production in these systems. In order to investigate the role of microzooplankton in grazing primary production in the Canary Current EBUE, grazing experiments were conducted as part of the Meteor M129 expedition. Water for experiments was taken from depths with the highest chlorophyll a concentrations and prescreened to remove mesozooplankton. Microzooplankton could consume between 60% and 95% of primary production, as measured by chlorophyll growth rates. When individual prey groups were examined, however, clear grazing effects were more mixed, with strong effects on nanoautotrophs and heterotrophic bacteria, varied effects on Synechococcus, and few statistically significant grazing effects on Prochlorococcus, pico-eukaryotes or heterotrophic nanoflagellates. The microplankton grazer community was diverse, with 22–33 ciliate and 10–26 dinoflagellate morphotypes. The large size range of the microplankton grazers and their high diversity resulted in a broad collective food niche and considerable niche overlap. This suggests that with sufficient diversity in the grazer community, changes in that community over the course of experiments may have minimal functional effect.
Heat stress leads to rapid lipid remodeling and transcriptional adaptations in Nicotiana tabacum pollen tubes
Authors: Krawczyk Hannah Elisa , Rotsch Alexander Helmut , Herrfurth Cornelia , Scholz Patricia , Shomroni Orr , Salinas-Riester Gabriela , Feussner Ivo , Ischebeck Till
Published: March 2022

After reaching the stigma, pollen grains germinate and form a pollen tube that transports the sperm cells to the ovule. Due to selection pressure between pollen tubes, pollen grains likely evolved mechanisms to quickly adapt to temperature changes to sustain elongation at the highest possible rate. We investigated these adaptions in tobacco (Nicotiana tabacum) pollen tubes grown in vitro under 22°C and 37°C by a multi-omics approach including lipidomic, metabolomic, and transcriptomic analysis. Both glycerophospholipids and galactoglycerolipids increased in saturated acyl chains under heat stress (HS), while triacylglycerols (TGs) changed less in respect to desaturation but increased in abundance. Free sterol composition was altered, and sterol ester levels decreased. The levels of sterylglycosides and several sphingolipid classes and species were augmented. Most amino acid levels increased during HS, including the noncodogenic amino acids γ-amino butyrate and pipecolate. Furthermore, the sugars sedoheptulose and sucrose showed higher levels. Also, the transcriptome underwent pronounced changes with 1,570 of 24,013 genes being differentially upregulated and 813 being downregulated. Transcripts coding for heat shock proteins and many transcriptional regulators were most strongly upregulated but also transcripts that have so far not been linked to HS. Transcripts involved in TG synthesis increased, while the modulation of acyl chain desaturation seemed not to be transcriptionally controlled, indicating other means of regulation. In conclusion, we show that tobacco pollen tubes are able to rapidly remodel their lipidome under HS likely by post-transcriptional and/or post-translational regulation.