bluuebunny/crossref_metadata_2025_split huggingface dataset:
The VarA-CsrA regulatory pathway influences cell shape in Vibrio cholerae
Authors: Rocha Leonardo F. Lemos , Peters Katharina , Depelteau Jamie S. , Briegel Ariane , Vollmer Waldemar , Blokesch Melanie 
Published: September 2021

AbstractDespite extensive studies on the curve-shaped bacterium Vibrio cholerae, the causative agent of the diarrheal disease cholera, its virulence-associated regulatory two-component signal transduction system VarS/VarA is not well understood. This pathway, which mainly signals through the downstream protein CsrA, is highly conserved among gamma-proteobacteria, indicating there is likely a broader function of this system beyond virulence regulation. In this study, we investigated the VarA-CsrA signaling pathway and discovered a previously unrecognized link to the shape of the bacterium. We observed that varA-deficient V. cholerae cells showed an abnormal spherical morphology during late-stage growth. Through peptidoglycan (PG) composition analyses, we discovered that these mutant bacteria contained an increased content of disaccharide dipeptides and reduced peptide crosslinks, consistent with the atypical cellular shape. The spherical shape correlated with the CsrA-dependent overproduction of aspartate ammonia lyase (AspA) in varA mutant cells, which likely depleted the cellular aspartate pool; therefore, the synthesis of the PG precursor amino acid meso-diaminopimelic acid was impaired. Importantly, this phenotype, and the overall cell rounding, could be prevented by means of cell wall recycling. Collectively, our data provide new insights into how V. cholerae use the VarA-CsrA signaling system to adjust its morphology upon unidentified external cues in its environment.Significance StatementResponsible for the diarrheal disease cholera, the bacterium Vibrio cholerae tightly regulates its virulence program according to external stimuli. Here, we discovered that a sensing-response mechanism involved in the regulation of virulence also controls bacterial shape. We show that V. cholerae lacking this system lose their normal comma shape and become spherical due to an abnormal cell wall composition caused by metabolic changes that reduce available cell wall building blocks. Our study therefore sheds new light on how V. cholerae modulates its morphology based on environmental changes.
Diversity and dynamics of the CRISPR-Cas systems associated withBacteroides fragilisin human population
Authors: Lam Tony J. , Mortensen Kate , Ye Yuzhen 
Published: September 2021

AbstractCRISPR-Cas systems are adaptive immune systems commonly found in prokaryotes that provide sequence-specific defense against invading mobile genetic elements (MGEs). The memory of these immunological encounters are stored in CRISPR arrays, where spacer sequences record the identity and history of past invaders. Analyzing such CRISPR arrays provide insights into the dynamics of CRISPR-Cas systems and the adaptation of their host bacteria to rapidly changing environments such as the human gut. In this study, we utilized 601Bacteroides fragilisgenome isolates from 12 healthy individuals, 6 of which include longitudinal observations, and 222 availableB. fragilisreference genomes to update the understanding ofB. fragilisCRISPR-Cas dynamics and their differential activities. Analysis of longitudinal genomic data showed that some CRISPR array structures remained relatively stable over time whereas others involved radical spacer acquisition during some periods, and diverse CRISPR arrays (associated with multiple isolates) co-existed in the same individuals with some persisted over time. Furthermore, features of CRISPR adaptation, evolution, and microdynamics were highlighted through an analysis of host-MGE network, such as modules of multiple MGEs and hosts, reflecting complex interactions betweenB. fragilisand its invaders mediated through the CRISPR-Cas systems. This work demonstrates the power of using culture-based population genomics to reveal the activities and evolution of the CRISPR-Cas systems associated with gut bacteria in human population. We made available of all annotated CRISPR-Cas systems and their target MGEs, and their interaction network as a web resource athttps://omics.informatics.indiana.edu/CRISPRone/Bfragilis.
PAEP and cilia gene splicing changes in endometrial glands during the implantation window in women with recurrent pregnancy loss
Authors: Pearson-Farr J.E. , Wheway G , Jongen M.S.A , Goggin P. , Lewis R.M. , Cheong Y. , Cleal J.K. 
Published: September 2021

ABSTRACTEndometrial glands are essential for fertility, consisting of ciliated and secretory cells that facilitate a suitable uterine environment for embryo implantation. This study sought to determine whether an endometrial gland specific transcriptome and splicing profile are altered in women with recurrent pregnancy loss. Our data provide a comprehensive catalogue of cilia and PAEP gene isoforms and relative exon usage in endometrial glands. We report a previously unannotated endometrial gland cilia transcript GALNT11 and its susceptibility to exon skipping. Key endometrial receptivity gene transcripts are also reported to change in endometrial glands of women with recurrent pregnancy loss. The endometrial gland cilia and PAEP targets identified in this study could be used to identify a perturbed endometrium, isolate causes of recurrent pregnancy loss and develop targeted therapies in personalised medicine.
HIF-dependent CKB expression promotes breast cancer metastasis, whereas cyclocreatine therapy impairs cellular invasion and improves chemotherapy efficacy
Authors: Krutilina Raisa I. , Playa Hilaire , Brooks Danielle L. , Schwab Luciana P. , Parke Deanna N. , Oluwalana Damilola , Layman Douglas R. , Fan Meiyun , Johnson Daniel L. , Yue Junming , Smallwood Heather , Seagroves Tiffany N. 
Published: September 2021

AbstractThe oxygen-responsive Hypoxia Inducible Factor (HIF)-1 promotes several steps of the metastatic cascade. A hypoxic gene signature is enriched in triple negative breast cancers (TNBCs) and correlates with poor patient survival. Since inhibiting the HIF transcription factors with small molecules is challenging, we sought to identify genes downstream of HIF-1 that could be targeted to block invasion and metastasis. Creatine kinase brain isoform (CKB) was identified as a highly differentially expressed gene in a screen of HIF-1 wild type and knockout mammary tumor cells derived from a transgenic model of metastatic breast cancer. CKB is a cytosolic enzyme that reversibly catalyzes the phosphorylation of creatine, generating phosphocreatine (PCr) in the forward reaction, and regenerating ATP in the reverse reaction. Creatine kinase activity is inhibited by the creatine analog cyclocreatine (cCr). Loss and gain of function genetic approaches were used in combination with cCr therapy to define the contribution of CKB expression or creatine kinase activity to cell proliferation, migration, invasion, and metastasis in ER-negative breast cancers. CKB was necessary for cell invasion in vitro and strongly promoted tumor growth and metastasis in vivo. Similarly, cyclocreatine therapy repressed cell migration, cell invasion, formation of invadopodia, and lung metastasis. Moreover, in common TNBC cell line models, the addition of cCr to conventional cytotoxic chemotherapy agents was either additive or synergistic to repress tumor cell growth.
Antigen-derived peptides directly engage the unfolded-protein sensor IRE1α to curb cross-presentation by dendritic cells
Authors: Guttman Ofer , Thomas Adrien Le , Marsters Scot , Lawrence David A. , Gutgesell Lauren , Harnoss Jonathan M. , Haag Simone M. , Murthy Aditya , Strasser Geraldine , Modrusan Zora , Wu Thomas , Mellman Ira , Ashkenazi Avi 
Published: September 2021

ABSTRACTDendritic cells (DCs) promote adaptive immunity by cross-presenting antigen-based epitopes to CD8+ T cells. DCs process internalized protein antigens into peptides that enter the endoplasmic reticulum (ER) and upload onto major histocompatibility type I (MHC-I) protein complexes for cell-surface transport and cross-presentation. Perplexingly, DCs often exhibit activation of the ER-stress sensor IRE1α in the absence of classical ER stress—leaving the underlying mechanism unexplained. Here we show that antigen-derived hydrophobic peptides directly engage ER-resident IRE1α by masquerading as unfolded proteins. Furthermore, IRE1α activation depletes MHC-I heavy-chain mRNAs through regulated IRE1α-dependent decay (RIDD), thereby curtailing antigen cross-presentation. In tumor-bearing mice, IRE1α disruption increased MHC-I expression on tumor-infiltrating DCs, and enhanced recruitment and activation of CD8+ T cells. Moreover, IRE1α inhibition synergized with anti-PD-L1 antibody treatment to cause tumor regression. Our findings elucidate the mechanism and consequence of antigen-driven IRE1α activation in DCs, yielding a promising combination strategy for cancer immunotherapy.
Risk factors for the rice crop farming community in China: a documentary analysis of the challenges during post COVID-19
Authors: Niaz Ahsan , Asad Muhammad Mujtaba , Abdulmuhsin Amir. A. , Shavanov Musa , Churi Prathamesh 
Published: September 2021

PurposePandemics always have an impact on everything; for wildlife it is somehow positive and for human health and safety it is negative. But yet there is not any critique on its impact on the agriculture sector and farmer community. The world is not aware of the hazards which will be caused by crop loss. On the globe the largest country by population is China, where natives in China consume rice as staple food. In past few years, it was among the highest rice producing and consuming countries. Rice is planted in February to May mostly in China, and rice crop production is strongly dependent on preplanting activates which farmers are unable to perform because of the coronavirus disease 2019 (COVID-19) spread and the need to follow safety measures. So, the purpose of this documentary analysis is to indicate the impact of coronavirus disease on the agricultural sector in China specifically for rice production.Design/methodology/approachIn this article, a documentary analysis approach has been utilized. Moreover, due to the new and latest issue, not much research has been published in the context of the COVID-19 pandemic impact on the agriculture industry in China. Whereas, several online reports and expert reviews have been reviewed which have been published in online platforms and blogs websites. A total of 45 resources (journal articles, expert reviews) have been downloaded from reputed databases such as Scopus and Web of Science, out of which 31 of them were more relevant and related to the context of study.FindingsThe outcome based on this study has indicated that the rice cultivators and farmers are in uncertainty and not comfortable to work in their fields without proper safety measures due to the pandemic situation which will badly affect their lives and the economy of the country. Therefore, this study suggests that to overcome this issue, a proper safety framework is needed to be developed which can be implemented and which can facilitate the rice farming community.Practical implicationsAgriculture is important in so many ways including providing employment to the bulk of the population and providing the basic necessity of life and also contributing to the national economy. The outcome of this study will facilitate the agricultural scientist, economist and seasonal crop production stakeholders to indicate the most problematic domain and upcoming challenges faced by the rice farming community in China due to the COVID-19 pandemic.Originality/valueThis is the first documentary analysis which is addressing the current issues due to the COVID-19 pandemic in the agriculture industry and specifically in the rice cultivation and producing community safety concerns and issues in China which is the first and most affected nation due to the coronavirus.
Entrepreneurial intention of academic students in the time of COVID-19 pandemic
Authors: Krichen Kamel , Chaabouni Haithem 
Published: September 2021

PurposeThe purpose of this study was to investigate the consequences of the economic shock caused by the COVID-19 pandemic on the entrepreneurial intentions of academic students. In addition, this research examined whether the pandemic reinforces the tendency to operate new businesses or represents a barrier to the pursuit of entrepreneurial opportunities.Design/methodology/approachThis study was conducted with a sample of university students. Risk perception and contextual variables were measured. Information was collected from 308 university students enrolled at the University of Sfax (Tunisia) who participated by responding to a structured questionnaire distributed in electronic form by email.FindingsThe results show that university students perceive higher levels of personal entrepreneurial risk than other types of entrepreneurial risks (financial risk and social risk). Perceived financial risk only has a significant effect on entrepreneurial intention for students who view the COVID-19 crisis as an opportunity. Regarding perceived contextual support, only perceived educational support has a significant and positive effect on entrepreneurial intention.Research limitations/implicationsThe results have important practical implications for identifying entrepreneurial intentions. They indicate that universities have an essential role in providing educational support for students by implementing awareness and training programs for entrepreneurship. Furthermore, they reveal the differentiated effect of the COVID-19 crisis on the risk perceptions of participants according to their views of the crisis as a threat or as an opportunity.Originality/valueThis is one of few studies that have examined the impact of the COVID-19 pandemic (positive or negative) on the entrepreneurial intention of academic students.
Impacts of management at a local and landscape scale on pollinators in semi‐natural grasslands
Authors: Larkin Michelle , Stanley Dara A. 
Published: September 2021

Abstract

Managing farmland to benefit biodiversity is becoming increasingly necessary to combat biodiversity declines and maintain ecosystem services. Results‐based agri‐environmental schemes are a tool used to achieve this by paying farmers based on environmental results delivered. These schemes often utilise plant indicator species to assess results at field scale; however, it is unknown if focusing on enhancing a subset of one biodiversity group within results‐based schemes impacts wider biodiversity, and whether local‐scale implementation of results‐based schemes or/and the wider landscape are more important drivers of biodiversity patterns.

Insect pollinators provide important pollination services for many crop and wild plants, and as mobile organisms often experience landscape at large spatial scales. We tested whether insect pollinators are affected at local scale by a results‐based scheme scored based on plant indicators, or if landscape management is more important, and whether there were different responses between taxon‐specific groups. Bumblebees, solitary bees, hoverflies and butterflies were sampled using transects and pan traps in 23 fields with varying scores assigned by the scheme, situated in high‐intensity (≥65% improved grassland) or low‐intensity (≥65% semi‐natural grassland) landscapes.

Results indicate taxon‐specific responses to local and landscape management in semi‐natural grasslands. Bumblebees responded positively to local‐scale management in fields with higher floral diversity, whereas hoverflies and butterflies responded positively to low‐intensity landscape management.

Synthesis and applications. Using plant species as indicators for biodiversity in agri‐environment schemes can have indirect benefits for non‐target taxa like bumblebees, but broader indicators should be developed to incorporate other pollinator groups. Pollinator groups respond differently to local and landscape management in semi‐natural grasslands. Agri‐environmental management should consider a range of different management measures and landscape scale approaches where possible, to maximise benefits for a range of pollinator taxa.
Tracking wildlife energy dynamics with unoccupied aircraft systems and three‐dimensional photogrammetry
Authors: Shero Michelle R. , Dale Julian , Seymour Alexander C. , Hammill Mike O. , Mosnier Arnaud , Mongrain Samuel , Johnston David W. 
Published: September 2021

Abstract

We present a novel application using unoccupied aircraft systems (UAS; drones) for structure‐from‐motion three‐dimensional (3‐D) photogrammetry of multiple, free‐living animals simultaneously. Pinnipeds reliably haul out on shore for pupping and breeding each year, accompanied by dramatic female‐to‐pup mass transfer over a short lactation period and males lose mass while defending mating territories. This provides a tractable study system for validating the use of UAS as a non‐invasive tool for tracking energy dynamics in wild populations.

UAS imagery of grey seals Halichoerus grypus was collected at Saddle Island, Nova Scotia. A multirotor UAS was piloted in 360‐degree orbits around relatively dense animal aggregations and georeferenced images were used for construction of a 3‐D point cloud, orthomosaic and Digital Surface Model for animal volumetric measurements. Directly following UAS survey, a subset of adult females were hand‐measured (morphometrics, blubber depth, n = 21 handlings [15 were unique animals]) and female–pup pairs were weighed (adult females: n = 32 [24]; pups: n = 33 [23]) to validate that UAS 3‐D photogrammetric models provided accurate animal volume and mass estimates.

UAS two‐dimensional body length measurements were sensitive to animal recumbency and posture. The new UAS 3‐D photogrammetric method overcame these constraints, and aerial‐derived body volume measurements were equivalent to those collected from the ground. UAS body volume measurements precisely predicted ‘true’ body mass (mean absolute error, adult female: 3.8 kg, 2.1% body mass; pup: 4.1 kg, 9.8%), and exhibited a stronger relationship with total body mass than with blubber volume.

The method was applied to 673 free‐living animals to characterize volume and mass dynamics across lactation and breeding for a much larger sample size than would be possible using traditional ground methods. Indeed, 1–46 animals (M ± SE: 9.2 ± 1.2) were modelled concurrently within the focal area of a UAS flight. Application of the method also captured significant inter‐annual variation in body volume/mass dynamics, and female‐to‐pup energy transfer efficiencies were lower when there was low sea ice extent. The UAS 3‐D photogrammetric method presented in this study is likely to be broadly applicable to other species, and the ability to measure whole groups of free‐living animals at once makes strides towards ‘weighing populations’.
Rural broadband speeds and business startup rates
Authors: Deller Steven , Whitacre Brian , Conroy Tessa 
Published: September 2021

AbstractUsing 2014 U.S. nonmetropolitan county‐level data, we explore the relationship between broadband speeds and business startup rates. Rural development policy discussions have presumed that access to broadband has become a necessary, although not sufficient, condition for economic growth and development. The relationship between broadband access on business startups, which are vital to local economic vibrancy, may be key to understanding the link between broadband and growth. In this study, we explore how qualitative features of broadband influence startup rates across different types of industries. To refine our insights into these relationships, we look at broadband by speed (both download and upload coverage across four speed categories). We also consider the importance of mobile broadband availability, which is often ignored in empirical studies. Because of the presence of spatial dependency within the data and the fact that data on business startup rates is limited to the minority of establishments that have employees, we use a Bayesian spatial Tobit estimator. After controlling for a host of variables likely to influence economic growth, we find that broadband coverage does matter and that download speeds tend to be more important than upload speeds. This pattern holds for mobile coverage as well. Perhaps the most important finding is that the results vary across business type: what matters for new businesses in one industry may not matter for other industry classifications. In the end, our results reaffirm the policy notion that access to broadband is increasingly relevant to rural entrepreneurship.
Are we ‘gritty’ enough? The importance of ‘grit’ in O&G training: Association of passion and perseverance with burnout, thriving and career progression
Authors: Lucky Tarana , Lowe Belinda , Arafat Yasser , Rathbone Evelyne , Angstetra Donald 
Published: September 2021

BackgroundObjective assessment of grit and its association with burnout in obstetrics and gynaecology (O&G) training is underexplored.AimThis study utilises the Short Grit Scale and the Oldenburg Burnout Inventory to investigate the association of grit with burnout, thriving and career progression among O&G trainees and Fellows in Australia/New Zealand.Materials and MethodsA cross‐sectional survey of the RANZCOG (Royal Australian and New Zealand College of Obstetricians and Gynaecologists) members was conducted. Participants were categorised by seniority level (core trainees, advanced trainees and Fellows). Mean grit and burnout scores were compared with one‐way analyses of variance. Correlation between grit and burnout was estimated using Pearson’s correlation coefficient. Logistic regression models were used to determine factors associated with high vs low burnout. Grit was categorised as low/medium/high for regression models.ResultsA total of 751 (26%) participants completed the survey. Fellows reported higher mean grit than core (P = 0.02) and advanced trainees (P = 0.03), and lower mean burnout than core trainees (P < 0.001). Moderate negative correlation was demonstrated between grit and burnout scores (r = −0.34). In the multivariable model, only seniority (adjusted adds ratio (OR): 0.40 for Fellows vs core trainees, P = 0.008) and grit levels (adjusted OR:4.52 for low versus high, P < 0.001; 2.32 for low vs medium, P = 0.001) were significantly associated with burnout.ConclusionThis study demonstrates the protective role of grit in combating burnout among RANZCOG trainees and Fellows. While further well‐designed studies are warranted, findings from our study are expected to help the College in developing targeted interventions and subsequently minimise burnout‐related adverse outcomes in high‐risk groups.
Letter: universal screening for hepatitis C in pregnant women, children and adolescents
Authors: Garrido Isabel , Macedo Guilherme 
Published: September 2021

LINKED CONTENTThis article is linked to Indolfi et al and Indolfi & Lucenteforte papers. To view these articles, visit https://doi.org/10.1111/apt.16037 and https://doi.org/10.1111/apt.16577