bluuebunny/crossref_metadata_2025 huggingface dataset:
Ensuring robust radiological risk assessment for wildlife: insights from the International Atomic Energy Agency EMRAS and MODARIA programmes
Authors: Beresford N A , Beaugelin-Seiller K , Barnett C L , Brown J , Doering C , Caffrey E , Johansen M P , Melintescu A , Ruedig E , Vandenhove H , Vives I Batlle J , Wood M D , Yankovich T L , Copplestone D
Published: May 2022

In response to changing international recommendations and national requirements, a number of assessment approaches, and associated tools and models, have been developed over the last circa 20 years to assess radiological risk to wildlife. In this paper, we summarise international intercomparison exercises and scenario applications of available radiological assessment models for wildlife to aid future model users and those such as regulators who interpret assessments. Through our studies, we have assessed the fitness for purpose of various models and tools, identified the major sources of uncertainty and made recommendations on how the models and tools can best be applied to suit the purposes of an assessment. We conclude that the commonly used tiered or graded assessment tools are generally fit for purpose for conducting screening-level assessments of radiological impacts to wildlife. Radiological protection of the environment (or wildlife) is still a relatively new development within the overall system of radiation protection and environmental assessment approaches are continuing to develop. Given that some new/developing approaches differ considerably from the more established models/tools and there is an increasing international interest in developing approaches that support the effective regulation of multiple stressors (including radiation), we recommend the continuation of coordinated international programmes for model development, intercomparison and scenario testing.
Synthesis and characterization of pristine and strontium-doped zinc oxide nanoparticles for methyl green photo-degradation application
Authors: Akram Rizwan , Almohaimeed Ziyad M , Bashir Adeela , Ikram Muhammad , Qadir Karwan Wasman , Zafar Qayyum
Published: May 2022

Herein we describe an effective route for the degradation of methyl green (MG) dye under visible light illumination by pristine and strontium (Sr)-doped zinc oxide (ZnO) photocatalysts (synthesized by the simple chemical precipitation method). The x-ray diffraction structural analysis has confirmed that both photocatalysts exhibit the hexagonal wurtzite structure; without any additional phase formation in Sr-doped ZnO, in particular. The optical properties of the synthesized photocatalysts have been investigated using UV–vis absorption spectroscopy in the wavelength range of 250–800 nm. Through Tauc’s plot, the slight decrease from 3.3 to 3.2 eV in band gap energy has been elucidated (in the case of Sr-doped ZnO), which has been further confirmed by the quenching in the intensity of Photoluminescence (PL) emission spectrum. This may be due to sub-band level formation between valence and conduction band, caused by the impregnation of Sr2+ ions into ZnO host. The morphological study has also been performed using Field Emission Scanning Electron Microscope, which indicates nanoparticles (NPs) based surface texture for both photocatalysts. During the photocatalytic activity study, after 30 min irradiation of visible light, ∼65.7% and ∼84.8% photocatalytic degradation of MG dye has been achieved for pristine and Sr-doped (2 wt%) ZnO photocatalysts, respectively. The rate of photocatalytic reaction (K) has been observed to be ∼0.06399 min−1 for Sr-doped (2 wt%), whereas nearly half magnitude ∼0.03403 min−1 has been observed for pristine ZnO, respectively. The significantly improved photodegradation activity may be ascribed to the relatively broader optical absorption capability, surface defects and the enhanced charge separation efficiency of the Sr-doped ZnO photocatalyst.
2D spin transport through graphene-MnBi2Te4 heterojunction
Authors: Chen Xi , Lin Zheng-Zhe
Published: May 2022

The development of two-dimensional (2D) magnetic semiconductors promotes the study of nonvolatile control of magnetoelectric nanodevices. MnBi2Te4 is the first realization of antiferromagnetic topological insulator. In semiconductor circuits, metal-semiconductor contacts are usually essential. In future all-carbon circuits, graphene is a promising material for 2D conductive connections. This work studies electronic transport through graphene-MnBi2Te4-graphene junctions. We find that graphene-MnBi2Te4 interfaces are perfect Ohmic contacts, which benefits the use of MnBi2Te4 in carbon circuits. The currents through MnBi2Te4 junctions possess high spin polarization. Compared with usual van der Waals junctions, lateral graphene-MnBi2Te4-graphene junctions present a lower barrier and much higher conductance to electrons. These findings may provide guidance for further study of 2D spin filtering.
Urchin-like PdOs nanostructure for hydrogen evolution electrocatalysis
Authors: Wang Ziqiang , Wang Peng , Mao Qiqi , Tian Wenjing , Xu You , Li Xiaonian , Wang Liang , Wang Hongjing
Published: May 2022

The compositional and structural engineering of advanced nanomaterials for hydrogen evolution reaction (HER) is highly necessary for efficient hydrogen production. Herein, PdOs nanospine assemblies (PdOs NAs) with urchin-like structures are fabricated via one-step route using DM-970 and KBr as surfactant agent and capping agent, respectively. Benefiting from electronic effect and multi-branched structure, the PdOs NAs exhibit superior performance for HER in alkaline and neutral solutions, requiring overpotentials of 28 and 35 mV at −10 mA cm−2, respectively, as well as superior long-term stability. This study offers a universal approach for the fabrication of active Pd-based catalysts with multi-branched morphology for efficient water electrolysis and beyond.
Compressive sampling system based on random demodulation for active and passive structural health monitoring
Authors: Liang Dong , Han Qingbang , Cai Yuhang , Yu Kaijun , Zhang Yarong
Published: May 2022

Structural health monitoring (SHM) is a revolutionary and innovative technique for determining structural integrity. It has broad application prospects in industrial equipment and infrastructure such as aircrafts, bridges and buildings. SHM system is used to monitor and diagnose the damages of these large structures, and it requires to install large sensor networks in or on large structures such as aircraft wings and airframes. The large number of sensors results in a very large amount of data for excited and received signals, especially for ultrasonic guided wave-based SHM with high frequency signals. According to the traditional Nyquist sampling theorem, the sampling rate is at least 2 times higher than the highest frequency of the received signal. The high sampling rate and the large amount of data pose a serious challenge on the signal acquisition, transmission, storage, and processing equipment, especially in the case that the signal needs to be transmitted to the base station for processing in real time. Therefore, how to compress and sample signals obtained by large sensor networks to improve monitoring efficiency and reduce costs is a research hotspot in current SHM. This paper adopts compressive sensing (CS) theory which has appeared in recent years to solve the big data and high frequency acquirement problem of SHM. The random demodulation system is chosen to realize CS, and the corresponding hardware and software systems are designed, which are achieved to compress and sample signal and reduce the sampling rate and the amount of data at the same time. The active and passive SHM signals based on piezoelectric sensor networks are compressed and sampled, and the new method are compared with the traditional Nyquist sampling in the experiment. The results show the effectiveness of the proposed method.
Farmer Perception and Economic Prospect of Stingless Bee (Hymenoptera: Apidae: Meliponini) Development in West Halmahera
Authors: Salatnaya H , Fuah A M , Sumantri C , Kahono S , Widiatmaka
Published: May 2022

Stingless bees are social bees distributed in Indonesia, including West Halmahera. However, they are not widely known for their value for human health, their role as pollinators, and how to cultivate them. West Halmahera has potencies to develop stingless bees due to its supportive agricultural environment. The aims of this research were to know the community perception of meliponiculture development and to analyze its economic potencies. Community perception analysis (scoring by Likert scale) used purposive sampling for nine respondents who are cultivating stingless bees in their locations based on the suitability analysis. Economic analysis used BEP, R/C Ratio, and ROI. The results showed that he respondents had common knowledge about the bees but less capability to cultivate (55.56%). Ecosystem suitability in West Halmahera was in the high category (66.67%). Most farmers were in full support of the development of the stingless bees for improving the additional family income and it will increase the crops production. The economic analysis showed that initiating business on this insect was quite reasonable because the BEP was < Production (0.33), BEP price < selling price, so the farmers would get significant benefits from this enterprise, with ROI being 215% and R/C ratio >1.
Evaluation of Nutricell HyC® (combination of 25OHD3 and Vitamin C) Supplementation on Broiler Breeders Fertility in Laying Period
Authors: Setiyaningsih N , Sumiati  , Jayanegara A , Wardani W W
Published: May 2022

The main goal of broiler breeders management is producing fertilized egg that can be hatched and to generate hatching eggs that will result in saleable chicks. The purpose of this research was to evaluate the effects supplementation of Nutricell HyC® (combination of 25OHD3 and vitamin C) with various levels on the fertility of broiler breeders. This research used 6,158 female broiler breeders with Cobb strain which were distributed according to a completely randomized design into four experimental treatments, with five replicates of ± 308 birds each. The treatments were Nutricell HyC® supplementation with the levels of 0, 100, 200, and 400 g/ton feed. Parameters observed were the clear eggs, fertile eggs, infertile eggs, culling chicks and early embryo mortality. Data collected were processed using analysis of variance (ANOVA) and for comparing among different group means continued with the Duncan multiple range test. The results showed that Nutricell HyC® supplementation could reduce clear eggs compared to the control diet (P<0.05). Furthermore, the percentages of fertile eggs increased as the level of Nutricell HyC® (P<0.05). However, infertile eggs, culling chicks, early embryo mortality were not affected by the Nutricell HyC® supplementation. The conclusion of this research was suplementation of Nutricell HyC® 400 g/ton feed yielded the best fertility performance of broiler breeders.
Supplementation of phytase and its combination with xylanase, amylase and protease (XAP) on performance and bone mineralization of broiler chicken
Authors: Sidiq F , Ghane A E , Ridla M , Hermana W
Published: May 2022

Phytase is the most common enzyme used in broiler diet mainly to improve phosphorus (P) digestibility and reduce P excretion to environment, but its effectiveness together with other enzymes such as xylanase, amylase and protease (XAP) is not widely evaluated. Current study was conducted to evaluate the efficacy of Buttiauxella spp. phytase supplementation at 1000 FTU/kg alone and its combination with XAP (2000 U/kg xylanase, 200 U/kg amylase and 4000 U/kg protease) on broiler performance and bone mineralization. A total 2849 male broilers Lohmann Indian River (LIR) were randomly assigned to 7 treatments with 11 replications. Treatments were positive control (PC) using standard diet followed LIR recommendation, negative control 1 (NC1) with nutrient reduction of 0.19% units available P, 0.2% units calcium (Ca), 0.41% units crude protein (CP) and 69 kcal/kg AME, NC2 applied similar reduction except for AME which was 105 kcal/kg, and on top of NCs was phytase and/or XAP supplementation. NC1 and NC2 significantly (P<0.05) reduced body weight, mortality-corrected feed conversion ratio (McFCR) and toe ash percentage compared to PC. Phytase alone on top of NCs significantly (P<0.05) improved body weight, McFCR and toe ash percentage. Further, combination of phytase with XAP numerically showed better weight gain, McFCR and broiler index (BI). These data suggest phytase and/or XAP supplementation is effective to maintain broiler performance and toe ash under nutrient deficiency, this because enzymes able to reduce the anti-nutritional effect and lead to better nutrient digestibility.
Habitat stability shaped the demographic history of the Atlantic Forest endemic rodentEuryoryzomys russatus(Cricetidae: Sigmodontinae) during the Pleistocene
Authors: Abreu Edson Fiedler , Dalapicolla Jeronymo , Furini Paulo Roberto , De La Sancha Noé U , Jansa Sharon A , Percequillo Alexandre Reis
Published: May 2022

The oryzomyine rodent Euryzoryzomys russatus is endemic to the Atlantic Forest of South America, where it inhabits mostly pristine humid forests. Previous phylogeographical studies performed with limited sample sizes indicated that rivers and climatic oscillations might have driven the diversification of this species. Here, we used a more comprehensive database to revisit the phylogeography and demographic history of E. russatus. Our phylogenetic inferences and haplotype network recovered four groups within E. russatus, each of which diversified between 0.33 and 0.60 Mya. These groups are mostly allopatric and are structured latitudinally along the Atlantic Forest. We did not detect any genetic break related to the major river drainages. Species distribution models recovered similar suitable areas for E. russatus in the present and past times, suggesting stability in the geographical range during the Pleistocene. The most pronounced change was the expansion of suitable areas onto the emerged continental shelf during the Last Glacial Maximum. Demographic analyses showed evidence of population expansion during periods of lowered seal levels, especially for the haplogroup associated with the Serra do Mar forest refuge. Therefore, our results failed to support the hypothesis of riverine barriers and suggest that the diversification of E. russatus is explained better by forest refugial processes.
Association between cortical gyrification and white matter integrity in spinocerebellar ataxia type 3
Authors: Tang Jingyi , Xie Yue , Liao Weihua , Zhang Youming , Yang Fangxue , Zhao Linmei , Zhou Gaofeng , Zhang Yuanchao , Jiang Hong , Xing Wu
Published: May 2022

Gray matter volume and thickness reductions have been reported in patients with spinocerebellar ataxia type 3 (SCA3), whereas cortical gyrification alterations of this disease remain largely unexplored. Using local gyrification index (LGI) and fractional anisotropy (FA) from structural and diffusion MRI data, this study investigated the cortical gyrification alterations as well as their relationship with white matter microstructural abnormalities in patients with SCA3 (n = 61) compared with healthy controls (n = 69). We found widespread reductions in cortical LGI and white matter FA in patients with SCA3 and that changes in these 2 features were also coupled. In the patient group, the LGI of the left middle frontal gyrus, bilateral insula, and superior temporal gyrus was negatively correlated with the severity of depressive symptoms, and the FA of a cluster in the left cerebellum was negatively correlated with the Scale for the Assessment and Rating of Ataxia scores. Our findings suggest that the gyrification abnormalities observed in this study may account for the clinical heterogeneity in SCA3 and are likely to be mediated by the underlying white matter microstructural abnormalities of this disease.
Impact of a Rapid Molecular Test for Klebsiella pneumoniae Carbapenemase and Ceftazidime-Avibactam Use on Outcomes After Bacteremia Caused by Carbapenem-Resistant Enterobacterales
Authors: Satlin Michael J , Chen Liang , Gomez-Simmonds Angela , Marino Jamie , Weston Gregory , Bhowmick Tanaya , Seo Susan K , Sperber Steven J , Kim Angela C , Eilertson Brandon , Derti Sierra , Jenkins Stephen G , Levi Michael H , Weinstein Melvin P , Tang Yi-Wei , Hong Tao , Juretschko Stefan , Hoffman Katherine L , Walsh Thomas J , Westblade Lars F , Uhlemann Anne-Catrin , Kreiswirth Barry N
Published: May 2022

Background

Patients with bacteremia due to carbapenem-resistant Enterobacterales (CRE) experience delays until appropriate therapy and high mortality rates. Rapid molecular diagnostics for carbapenemases and new β-lactam/β-lactamase inhibitors may improve outcomes.

Methods

We conducted an observational study of patients with CRE bacteremia from 2016 to 2018 at 8 New York and New Jersey medical centers and assessed center-specific clinical microbiology practices. We compared time to receipt of active antimicrobial therapy and mortality between patients whose positive blood cultures underwent rapid molecular testing for the Klebsiella pneumoniae carbapenemase (KPC) gene (blaKPC) and patients whose cultures did not undergo this test. CRE isolates underwent antimicrobial susceptibility testing by broth microdilution and carbapenemase profiling by whole-genome sequencing. We also assessed outcomes when ceftazidime-avibactam and polymyxins were used as targeted therapies.

Results

Of 137 patients with CRE bacteremia, 89 (65%) had a KPC-producing organism. Patients whose blood cultures underwent blaKPC PCR testing (n = 51) had shorter time until receipt of active therapy (median: 24 vs 50 hours; P = .009) compared with other patients (n = 86) and decreased 14-day (16% vs 37%; P = .007) and 30-day (24% vs 47%; P = .007) mortality. blaKPC PCR testing was associated with decreased 30-day mortality (adjusted odds ratio: .37; 95% CI: .16–.84) in an adjusted model. The 30-day mortality rate was 10% with ceftazidime-avibactam monotherapy and 31% with polymyxin monotherapy (P = .08).

Conclusions

In a KPC-endemic area, blaKPC PCR testing of positive blood cultures was associated with decreased time until appropriate therapy and decreased mortality for CRE bacteremia, and ceftazidime-avibactam is a reasonable first-line therapy for these infections.
Treatment of Cutaneous Balamuthia mandrillaris Infection With Diminazene Aceturate: A Report of 4 Cases
Authors: Wang Lei , Li Bing , Zhao Tao , Wang Lu , Jian Zhe , Cheng Wenjing , Chen Jiaxi , Li Chunying , Wang Gang , Gao Tianwen
Published: May 2022

Four cases of cutaneous Balamuthia mandrillaris infection were treated with diminazene aceturate. One patient was cured with mainly monotherapy, 2 patients were cured with diminazene aceturate and excision, and 1 patient died of drug-induced liver damage. This is the first report of B. mandrillaris infection treated with diminazene aceturate.
Reliability and validity of the Arabic version of the Consultation and Relational Empathy (CARE) measure
Authors: Al-Habbal Khairat , Djoundourian Alicia , Nassar Elma , Tayara Ziad , Mercer Stewart W , Abi-Habib Rudy
Published: May 2022

Purpose

Empathy is the ability to communicate an understanding of an individual’s subjective experience. It plays a vital role in the physician–patient relationship and improves clinical outcomes. This increases the importance of measuring and studying empathy in the clinical setting. The Consultation and Relational Empathy (CARE) is a 10-item questionnaire that measures patient assessment of physician’s empathy in primary care. To our knowledge, there are no validated measures of empathy in the clinical setting in Arabic. This study aims at validating the CARE in Arabic.

Methods

Data collection took place between October 2019 and February 2020. A total of 220 patients completed the questionnaire which consisted of the 10 CARE items, participants’ opinions regarding the importance of each item, demographic information, and information about the consultation. The reliability and validity of the Arabic CARE were measured using Cronbach alpha, item-total correlations, and factor analysis. Construct validity was measured based on the overall patient satisfaction, and their satisfaction with the length of the consultation.

Results

High Cronbach alpha and item-total correlation reveal the internal consistency and homogeneity of the Arabic version. Our findings showed significant positive correlations between CARE score and each of the characteristics: overall satisfaction with the consultation, duration of the consultation, patients’ satisfaction with consultation duration and whether they would recommend the doctor to others.

Conclusion

The Arabic version of the CARE measure appears to be valid and reliable. It is available for use in research, education, and assessment of physicians’ empathy.
A systematic review of antimicrobial resistance in Neisseria gonorrhoeae and Mycoplasma genitalium in sub-Saharan Africa
Authors: Iwuji Collins , Pillay Diantha , Shamu Patience , Murire Mercy , Nzenze Susan , Cox Laura Ashleigh , Mullick Saiqa
Published: May 2022

Objectives

Limited antimicrobial resistance (AMR) surveillance coupled with syndromic management of sexually transmitted infections (STIs) in sub-Saharan Africa (SSA) could be contributing to an increase in AMR in the region. This systematic review aimed to synthesize data on the prevalence of AMR in common STIs in SSA and identify some research gaps that exist.

Methods

We searched three electronic databases for studies published between 1 January 2000 and 26 May 2020. We screened the titles and abstracts for studies that potentially contained data on AMR in SSA. Then we reviewed the full text of these studies to identify articles that reported data on the prevalence of AMR in Neisseria gonorrhoeae, Chlamydia trachomatis, Trichomonas vaginalis and Mycoplasma genitalium in SSA. We summarized the data using a narrative synthesis.

Results

The 40 included studies reported on AMR data from 7961 N. gonorrhoeae isolates from 15 countries in SSA and 350 M. genitalium specimens from South Africa. All four SSA regions reported very high rates of ciprofloxacin, tetracycline and penicillin resistance in N. gonorrhoeae. Resistance to cefixime or ceftriaxone was observed in all regions except West Africa. Azithromycin resistance, recommended as part of dual therapy with an extended-spectrum cephalosporin for gonorrhoea, was reported in all the regions. Both macrolide and fluoroquinolone-associated resistance were reported in M. genitalium in South Africa. Studies investigating AMR in C. trachomatis and T. vaginalis were not identified.

Conclusions

There is a need to strengthen AMR surveillance in SSA for prompt investigation and notification of drug resistance in STIs.
The C-Band All-Sky Survey (C-BASS): template fitting of diffuse galactic microwave emission in the northern sky
Authors: Harper S E , Dickinson C , Barr A , Cepeda-Arroita R , Grumitt R D P , Heilgendorff H M , Jew L , Jonas J L , Jones M E , Leahy J P , Leech J , Pearson T J , Peel M W , Readhead A C S , Taylor A C
Published: May 2022

The C-Band All-Sky Survey (C-BASS) has observed the Galaxy at 4.76 GHz with an angular resolution of 0${_{.}^{\circ}}$73 full-width half-maximum, and detected Galactic synchrotron emission with high signal-to-noise ratio over the entire northern sky (δ > −15○). We present the results of a spatial correlation analysis of Galactic foregrounds at mid-to-high (b > 10○) Galactic latitudes using a preliminary version of the C-BASS intensity map. We jointly fit for synchrotron, dust, and free–free components between 20 and 1000 GHz and look for differences in the Galactic synchrotron spectrum, and the emissivity of anomalous microwave emission (AME) when using either the C-BASS map or the 408-MHz all-sky map to trace synchrotron emission. We find marginal evidence for a steepening (<Δβ> = −0.06 ± 0.02) of the Galactic synchrotron spectrum at high frequencies resulting in a mean spectral index of <β> = −3.10 ± 0.02 over 4.76–22.8 GHz. Further, we find that the synchrotron emission can be well modelled by a single power law up to a few tens of GHz. Due to this, we find that the AME emissivity is not sensitive to changing the synchrotron tracer from the 408-MHz map to the 4.76-GHz map. We interpret this as strong evidence for the origin of AME being spinning dust emission.
DNA-PKcs-dependent phosphorylation of RECQL4 promotes NHEJ by stabilizing the NHEJ machinery at DNA double-strand breaks
Authors: Lu Huiming , Guan Junhong , Wang Shih-Ya , Li Guo-Min , Bohr Vilhelm A , Davis Anthony J
Published: May 2022

Non-homologous end joining (NHEJ) is the major pathway that mediates the repair of DNA double-strand breaks (DSBs) generated by ionizing radiation (IR). Previously, the DNA helicase RECQL4 was implicated in promoting NHEJ, but its role in the pathway remains unresolved. In this study, we report that RECQL4 stabilizes the NHEJ machinery at DSBs to promote repair. Specifically, we find that RECQL4 interacts with the NHEJ core factor DNA-PKcs and the interaction is increased following IR. RECQL4 promotes DNA end bridging mediated by DNA-PKcs and Ku70/80 in vitro and the accumulation/retention of NHEJ factors at DSBs in vivo. Moreover, interaction between DNA-PKcs and the other core NHEJ proteins following IR treatment is attenuated in the absence of RECQL4. These data indicate that RECQL4 promotes the stabilization of the NHEJ factors at DSBs to support formation of the NHEJ long-range synaptic complex. In addition, we observed that the kinase activity of DNA-PKcs is required for accumulation of RECQL4 to DSBs and that DNA-PKcs phosphorylates RECQL4 at six serine/threonine residues. Blocking phosphorylation at these sites reduced the recruitment of RECQL4 to DSBs, attenuated the interaction between RECQL4 and NHEJ factors, destabilized interactions between the NHEJ machinery, and resulted in decreased NHEJ. Collectively, these data illustrate reciprocal regulation between RECQL4 and DNA-PKcs in NHEJ.
Heritable base-editing in Arabidopsis using RNA viral vectors
Authors: Liu Degao , Xuan Shuya , Prichard Lynn E , Donahue Lilee I , Pan Changtian , Nagalakshmi Ugrappa , Ellison Evan E , Starker Colby G , Dinesh-Kumar Savithramma P , Qi Yiping , Voytas Daniel F
Published: May 2022

Heritable base-editing using a viral delivery system enables high-throughput functional analysis of genes in Arabidopsis.
Phosphatidylcholine:diacylglycerol cholinephosphotransferase’s unique regulation of castor bean oil quality
Authors: Demski Kamil , Jeppson Simon , Stymne Sten , Lager Ida
Published: May 2022

Castor bean (Ricinus communis) seed oil (triacylglycerol [TAG]) is composed of ∼90% of the industrially important ricinoleoyl (12-hydroxy-9-octadecenoyl) groups. Here, phosphatidylcholine (PC):diacylglycerol (DAG) cholinephosphotransferase (PDCT) from castor bean was biochemically characterized and compared with camelina (Camelina sativa) PDCT. DAGs with ricinoleoyl groups were poorly used by Camelina PDCT, and their presence inhibited the utilization of DAG with “common” acyl groups. In contrast, castor PDCT utilized DAG with ricinoleoyl groups similarly to DAG with common acyl groups and showed a 10-fold selectivity for DAG with one ricinoleoyl group over DAG with two ricinoleoyl groups. Castor DAG acyltransferase2 specificities and selectivities toward different DAG and acyl-CoA species were assessed and shown to not acylate DAG without ricinoleoyl groups in the presence of ricinoleoyl-containing DAG. Eighty-five percent of the DAG species in microsomal membranes prepared from developing castor endosperm lacked ricinoleoyl groups. Most of these species were predicted to be derived from PC, which had been formed by PDCT in exchange with DAG with one ricinoleoyl group. A scheme of the function of PDCT in castor endosperm is proposed where one ricinoleoyl group from de novo-synthesized DAG is selectivity transferred to PC. Nonricinoleate DAG is formed and ricinoleoyl groups entering PC are re-used either in de novo synthesis of DAG with two ricinoleoyl groups or in direct synthesis of triricinoleoyl TAG by PDAT. The PC-derived DAG is not used in TAG synthesis but is proposed to serve as a substrate in membrane lipid biosynthesis during oil deposition.
H-lignin can be deposited independently of CINNAMYL ALCOHOL DEHYDROGENASE C and D in Arabidopsis
Authors: Muro-Villanueva Fabiola , Kim Hoon , Ralph John , Chapple Clint
Published: May 2022

Lignin contributes substantially to the recalcitrance of biomass toward saccharification. To circumvent this problem, researchers have genetically altered lignin, although, in a number of cases, these efforts have resulted in an undesirable yield penalty. Recent findings have shown that by knocking out two subunits (MED5A and MED5B) of the transcriptional regulatory complex Mediator, the stunted growth phenotype of mutants in p-coumaroyl shikimate 3′-hydroxylase, reduced epidermal fluorescence 8-1 (ref8-1), can be alleviated. Furthermore, these plants synthesize a lignin polymer almost entirely derived from p-coumaryl alcohol. Plants deficient in cinnamyl alcohol dehydrogenase (CAD) are notable in that they primarily incorporate coniferaldehyde and sinapaldehyde into their lignin. We tested the hypothesis that by stacking mutations in the genes encoding for the CAD paralogs C and D on an Arabidopsis (Arabidopsis thaliana) med5a/5b ref8-1 genetic background, the biosynthesis of p-coumaryl alcohol would be blocked, making p-coumaraldehyde available for polymerization into a novel kind of lignin. The med5a/5b ref8-1 cadc cadd plants are viable, but lignin analysis demonstrated that they continue to synthesize p-hydroxyphenyl lignin despite being mutated for the CADs typically considered to be required for monolignol biosynthesis. In addition, enzyme activity tests showed that even in the absence of CADC and CADD, there is high CAD activity in stems. We tested the potential involvement of other CADs in p-coumaraldehyde biosynthesis in the quintuple mutant by mutating them using the CRISPR/Cas9 system. Lignin analysis demonstrated that the resulting hextuple mutant plants continue to deposit p-coumaryl alcohol-derived lignin, demonstrating a route for the synthesis of p-hydroxyphenyl lignin in Arabidopsis independent of four CAD isoforms.
Fats and Sugars Recruit Distinct Gut‐Brain Circuits To Control Food Intake And Reward
Authors: McDougle Molly , de Araujo Alan , Vergara Macarena , Singh Arashdeep , Yang Mingxin , Braga Isadora , de Lartigue Guillaume
Published: May 2022

The high‐fat high‐sugar food environment has been implicated as a driver of the obesity epidemic. Nodose ganglia (NG) neurons transmit post‐ingestive signals, including fat and sugar intake, from the gut to the brain. Previous data revealed distinct vagal circuits are required for post‐ingestive fat and sugar reinforcement, but whether these signals converge onto overlapping reward circuits is unclear.

Methods

To address this, we used FosTRAP mice to genetically label whole‐brain neuronal responses to discreet time‐restricted stimuli. Using genetic‐encoded reporter (tdTom) expression and cFos immunolabeling we compared neural responses to intragastric stimuli at two separate timepoints in the same animal.

Results

Repeated intragastric infusion of the same macronutrient resulted in high colocalization between tdTom and cFos labeling (>70%) in neurons of a previously identified gut‐reward circuit (NTS, PBN, SNc, dorsal striatum). Equicaloric infusion of fat or sugar at two separate timepoints significantly reduced colocalization of tdTom and cFos labeling (<30%), suggesting that fat and sugar recruit parallel but largely distinct reward circuits. Viral‐mediated caspase ablation of sugar‐sensing NG neurons abolished activation of the reward circuitry for sugar, but not fat; confirming this is a vagally‐mediated mechanism. Optogenetic stimulation of fat‐sensing NG neurons is sufficient to condition operant behavior. Microdialysis in response to equicaloric intragastric infusions of fat or sugar resulted in similar dopamine efflux in the dorsal striatum. To obtain the same level of dopamine efflux, more calories of an equicaloric fat‐sugar combination are required, correlating with compensatory increased intake of fat‐sugar solution.

Conclusion

There are labeled lines for vagally‐mediated fat or sugar reward. Reduced reward in response to fat‐sugar combinations may explain the inclination to overindulge in high‐fat high‐sugar foods, and have broad implications for the pathogenesis of obesity.
The impact of maternal dietary deficiencies in folic acid and choline on offspring neuronal function after hypoxia
Authors: Coonrod Sarah , Jadavji Nafisa M.
Published: May 2022

Ischemic stroke is an unmet medical need within the clinical population and is associated with significant mortality and morbidity. Nutrition is a modifiable risk factor for ischemic stroke. A maternal diet that provides adequate nutrition during pregnancy and lactation is vital to the neurodevelopment of offspring. Deficiencies in nutrients during fetal growth can lead to altered early life nutritional programming, such as spina bifida, a neural tube defect. There is an opportunity for advancing therapeutic intervention by completing additional research aimed at understanding the mechanistic impact of maternal nutrition on offspring ischemic stroke. Dietary deficiencies of one‐carbon (1C) metabolites have been associated with an increased risk for stroke. 1C metabolites include folic acid and choline which play a vital role in early life neurodevelopment. Data from our laboratory demonstrates that maternal dietary deficiencies in these vitamins and nutrients impact stroke outcome in 2‐month‐old male and female offspring, however, the mechanisms through which this occurs remain unknown. The aim of the present study was to investigate the impact of maternal dietary deficiencies in folic acid or choline on neuronal viability. This project used hypoxia as an in vitro model of stroke. Prior to mating, female mice were placed on a control, folic acid, or choline deficient diet for 4 weeks. Primary neurons were isolated from embryonic tissue, grown in culture, and exposed to hypoxia, after which cells were returned to normoxia. Twenty‐four hours after hypoxia, neuronal viability and apoptosis was measured in cultures. Our results demonstrate that offspring neurons from deficient mothers had reduced cell viability. There was also a change in the level of apoptosis between maternal dietary groups and treatments. These results suggest that a maternal dietary deficiency during pregnancy negatively impacts neurons after hypoxia.
Effects of berberine on neurological recovery after spinal cord injury in rats
Authors: Duan Hubin , Yang Xin , Hao Chunyan , Xue Wen , Qiao Xiaohong
Published: May 2022

Objective

Secondary inflammation after spinal cord injury is an important cause of neurological dysfunction. At present, there are relatively few effective drugs as an inflammatory inhibitor of spinal cord injury. Berberine is a common inflammatory inhibitor of traditional Chinese medicine extract, so we tried to explore the therapeutic significance of this drug for spinal cord injury.

Materials and methods

The SD rats were randomly divided into three groups: sham operation group(n=30), non‐intervention group(n=30), and Berberine intervention group(n=30). The T10 SCI model was established by Allen's percussion method. BBB score, SEP and MEP latency and amplitude were used to evaluate hind limb function. The water content of spinal cord was measured. The spinal cell structure was observed by HE and Nissl staining and electron microscopy. The motor function was detected by SEP(Somatosensory Evoked Potential) and MEP(motor evoked potential. BBB(Basso‐Beattie‐Bresnahan) score was used to evaluate the hind limb function of rats.

Results

The BBB score of berberine in SCI model was significantly lower than that in sham operation group from postoperative day 1 to 31. Hindlimb function of Berberine intervention group began to recover faster than the non‐intervention group on day 10 (p < 0.05). The latency of SEP and MEP after spinal cord injury was significantly longer than that of sham operation group (p < 0.05), but there was no significant difference in the latency of SEP and MEP between the two groups (p > 0.05). The amplitude of SEP and MEP in rats after spinal cord injury was significantly lower than that in the sham operation group (P < 0.05). In addition, after berberine treatment, the degree of spinal cord edema in rats decreased to some extent (p < 0.05).

Conclusion

Berberine can promote the recovery of injured spinal cord to some extent, which may be related to its inflammatory inhibition.
Lacritin Bactericidal Peptide N‐104 Targeting of Inner Membrane Transporters FeoB and PotH (SpuG) Individually Absent in N‐104 Resistant Strains of Human Opportunistic Pathogen, P. aeruginosa PA14
Authors: Sharifian Gh. Mohammad , Gadjeva Mihaela G. , Venter Henrietta , Laurie Gordon W.
Published: May 2022

Through an unbiased screen of the E. coli Keio collection of 3,985 nonessential gene knockouts, we have discovered that inner membrane putrescine and ferrous iron transporters PotH and FeoB each play roles in the bactericidal mechanism of tear lacritin peptide ‘N‐104’ ‐ possibly involving outer‐membrane translocation by lipoprotein YaiW with which it binds and when absent confers N‐104 resistance. The results were confirmed in the human opportunistic pathogen, P. aeruginosa PA14, and in a robust C. elegans‐based liquid infection assay. Does periplasmic N‐104 directly or indirectly target PotH and/or FeoB? His‐tagged FeoB (P. aeruginosa) and PotH (E. coli) extracted in lysis buffer containing 2% Dodecyl‐b‐D‐maltopyranoside were purified on Ni‐Sepharose columns, concentrated on 50 kDa (FeoB) or 30 kDa (PotH) Amicon cutoff membranes, and then added in equal amounts in 150 mM NaCl column buffer to SulfoLink® immobilized Cys‐N‐104 or to negative control Cys‐C‐95 columns. After overnight incubation at 4°C and collection of the flow through, columns were washed with 25 column volumes of 150 mM KCl before elution via a gradient of column buffer containing 300, 500, or 1000 mM KCl. Whereas FeoB and PotH were detected only in the flow through off of C‐95, 500 mM KCl was required for elution off of N‐104. PotH inwardly transports putrescine, the predominant polyamine in bacterial cells (10 ‐ 30 mM) that is essential for optimal bacterial cell growth and proliferation. FeoB is the major mediator of ferrous iron uptake in P. aeruginosa, E. coli, H. pylori, and some other species, and is a well‐recognized virulence factor. Given that none of those proteins are essential for the bacterial survival, we hypothesize that N‐104 might either disturb putrescine or ferrous iron regulation, or employ each to trigger programmed cell death via uncharacterized YbdM predicted to have transcription regulatory region activity also discovered to bind N‐104, and when absent confers N‐104 resistance. This study uncovers new virulence factors, and a novel method of bacterial cell death by a natural peptide component of human tears and apparently of plasma.
Client Specificity of an ATP‐independent Chaperone is Regulated by a Temperature Sensitive Switch
Authors: Siegel Alex , Ji Shuiling , McAvoy Camille , Lam Vinh , Liang Fu‐Cheng , Kroon Gerard , Miaou Emily , Griffin Patrick , Grimm Bernhard , Wang Peng , Wright Peter , Shan Shu‐ou
Published: May 2022

The chloroplast signal recognition particle 43 (cpSRP43) is an ATP‐independent chaperone that delivers the light‐harvesting chlorophyll‐binding proteins (LHCPs) to the thylakoid membrane while also maintaining the levels of tetrapyrrole biosynthesis (TBS) proteins. How cpSRP43 coordinates these roles to protect two very different classes of clients has remained unclear. We show that cpSRP43 samples two distinct conformations: a well‐folded closed state that protects unfolded membrane protein LHCPs through contacts with its substrate binding domain (SBD) and an open state with a partially disordered SBD that is less active towards LHCP but remains effective at protecting TBS proteins from heat‐induced aggregation. Binding of the additional cpSRP54 subunit stimulates cpSRP43's chaperone activity towards LHCPs by stabilizing the closed state but inhibits its chaperone activity towards TBS proteins. Strikingly, the cpSRP43‐cpSRP54 binding affinity is greatly weakened at high temperatures. Taken together, this shows that temperature can direct cpSRP43 towards one of these two client pathways. Under normal conditions, most cpSRP43 is tightly bound to cpSRP54 in the closed state and is primarily dedicated to the protection and delivery of LHCPs. However during heat stress, as chloroplast proteins become increasingly susceptible to heat‐induced aggregation, cpSRP43 dissociates from cpSRP54 and is rapidly repurposed into a stress‐responsive chaperone for TBS proteins.
Proximity‐dependent sensors for signaling
Authors: Gingras Anne‐Claude , Martin Claire , Hesketh Geoffrey , Al Mismar Rasha , Knight James D. , Go Christopher , Dionne Ugo
Published: May 2022

Understanding dynamic subcellular organization in living cells is key to unravelling mechanisms of intracellular signaling that goes awry in disease. Using proximity‐dependent biotinylation (BioID), we first established a reference map for the human cell at steady state (Go et al., Nature, 2021; humancellmap.org) that serves to identify protein baits that can report on the recruitment of proteins to selected organelles or subcellular structures. These BioID “sensors” can then be applied to look at dynamic changes in signaling. For example, exploiting late endosome/lysosome BioID sensors (VAMP7 and VAMP8), we recently revealed new intricacies in the regulation of amino acid sensing pathways (Hesketh et al., Science, 2020). We also coupled BioID sensor profiling to CRISPR‐mediated ablation of pathway components to investigate the consequences on the environment detected by the sensor. Using these approaches, we recently used fast‐acting biotinylation enzymes, including miniTurbo, to provide a space and time‐resolved analysis of EGFR pathway activation, revealing previously uncharacterized associations. This presentation will revisit key principles of dynamic organelle mapping in living cells, and the utilization of coincidence detection for dynamic proximal interactomes.
How does cohesin organize the 3D genome?
Authors: Finkelstein Ilya , Zhang Hongshan , Shi Zhubing , Kim Yoori , Yu Hongtao , Bai Xiao‐chen
Published: May 2022

Cohesin and CCCTC‐binding factor (CTCF) are key regulatory proteins of three‐dimensional (3D) genome organization. I will present direct evidence that cohesin extrudes DNA loops that are anchored by CTCF proteins in specific orientations. CTCF binding polarity controls cohesin‐mediated DNA looping. Using single‐molecule imaging of CTCF‐cohesin collisions, we demonstrate that the N‐terminus of CTCF must be oriented towards cohesin to block its ability to compact DNA. C‐terminally oriented CTCF accelerates DNA compaction by cohesin. Oriented inactive Cas9 and Cas12a ribonucleoproteins exhibit similar polar effects on DNA compaction by cohesin. RNA‐DNA hybrids (R‐loops), such as those that occur at highly transcribed genes, efficiently block cohesin‐mediated DNA compaction. Our results explain long‐standing puzzles regarding how CTCF and transcription shape the 3D genome.
A sex‐specific role for long noncoding RNA in depression susceptibility and resilience
Authors: Issler Orna
Published: May 2022

Major depressive disorder is a common, chronic, and debilitating disorder. Depression strikes women twice more than men, yet the molecular mechanisms contributing to this sex difference are poorly understood. Epigenetic processes that mediate interactions between genetic predispositions and stressful life experiences are known to play a critical role in depression risk. Here, we explored the roles of long noncoding RNAs (lncRNAs), a novel class of epigenetic regulators that are enriched in the primate brain, in depression in both sexes. To that end, we integrated cutting‐edge molecular, bioinformatics, behavioral, and physiological approaches spanning both humans and mice. We found that lncRNAs are robustly regulated in a sex‐specific manner in postmortem brain tissue from depressed humans compared to healthy controls. Utilizing a genome‐wide “guilt‐by‐association” bioinformatics approach, we identified sex‐specific lncRNAs linked to depression. One of these targets, LINC00473, is neuronal‐enriched and is specifically downregulated in the prefrontal cortex of depressed females only. To determine a causal role for LINC00473 in depression, we virally expressed it in mice of both sexes’ prefrontal cortex neurons followed by a behavioral examination. This manipulation mirrored the human sex‐specific phenotype, as expressing LINC00473 induced stress resilience in females only, which was accompanied by changes in synaptic function and gene expression. Another lncRNA we identified (RP11‐298D21.1) is upregulated in the depressed female brain, and therefore we named it FEDORA (FEmale DepressiOn lncRnA). FEDORA is expressed in oligodendrocytes and neurons; thus, we utilized a cell type‐specific viral expression system to test its role in both cell types. We found that expressing FEDORA promoted depression‐like behaviors only in female mice in both cell types. However, these behavioral changes were associated with cell‐type‐specific transcriptional changes, as well as altered electrophysiological and morphological features. Finally, we found that circulating FEDORA levels reflect its brain expression profile: blood FEDORA levels are elevated only in depressed women, suggesting FEDORA as a potential sex‐specific biomarker for a depression diagnosis. Together, this work establishes that lncRNAs play a key role in depression and contribute to the sex differences of this disorder. These findings provide a new view of molecular adaptations contributing to depression risk and point to promising targets for developing novel depression diagnosis and treatment tools.
RNA Modifiers Multitasking On Chromatin
Authors: Xhemalçe Blerta
Published: May 2022

It is becoming increasingly clear that in mammalian cells, RNA Polymerase II is regulated at the level of promoter proximal pause release and productive elongation prompted by P‐TEFb kinase activity. As a result, P‐TEFb recruitment and activation at particular gene promoters is a key regulatory switch, the understanding of which can open the way to new therapeutic opportunities for many diseases including cancer. P‐TEFb activity is inhibited by its interaction with the 7SK ribonuclear protein complex (RNPc), which sequesters unutilized P‐TEFb in the nucleoplasm; interestingly, recent studies, including ours, have shown that this RNPc often regulates P‐TEFb recruitment and activity directly on chromatin at the promoter of paused genes. Here, we will present our data showing how MePCE, an RNA methyltransferase of the 7SK RNPc, multitasks on chromatin to coordinate transcription and RNA processing with other DNA‐templated activities, including DNA repair.