bluuebunny/crossref_metadata_2025 huggingface dataset:
An inquiline mosquito modulates microbial diversity and function in an aquatic microecosystem
Authors: Arellano Aldo A. , Young Erica B. , Coon Kerri L.
Published: March 2024

Understanding microbial roles in ecosystem function requires integrating microscopic processes into food webs. The carnivorous pitcher plant, Sarracenia purpurea, offers a tractable study system where diverse food webs of macroinvertebrates and microbes facilitate digestion of captured insect prey, releasing nutrients supporting the food web and host plant. However, how interactions between these macroinvertebrate and microbial communities contribute to ecosystem functions remains unclear. We examined the role of the pitcher plant mosquito, Wyeomyia smithii, in top‐down control of the composition and function of pitcher plant microbial communities. Mosquito larval abundance was enriched or depleted across a natural population of S. purpurea pitchers over a 74‐day field experiment. Bacterial community composition and microbial community function were characterized by 16S rRNA amplicon sequencing and profiling of carbon substrate use, bulk metabolic rate, hydrolytic enzyme activity, and macronutrient pools. Bacterial communities changed from pitcher opening to maturation, but larvae exerted minor effects on high‐level taxonomic composition. Higher larval abundance was associated with lower diversity communities with distinct functions and elevated nitrogen availability. Treatment‐independent clustering also supported roles for larvae in curating pitcher microbial communities through shifts in community diversity and function. These results demonstrate top‐down control of microbial functions in an aquatic microecosystem.
Expression of bond‐related behaviors affects titi monkey responsiveness to oxytocin and vasopressin treatments
Authors: Witczak Lynea R. , Samra Jaclyn , Dufek Madison , Goetze Leana R. , Freeman Sara M. , Lau Allison R. , Rothwell Emily S. , Savidge Logan E. , Arias‐del Razo Rocío , Baxter Alexander , Karaskiewicz Chloe L. , Ferrer Emilio , Bales Karen L.
Published: March 2024

Social bonds influence physiology and behavior, which can shape how individuals respond to physical and affective challenges. Coppery titi monkey (Plecturocebus cupreus) offspring form selective bonds with their fathers, making them ideal for investigating how father–daughter bonds influence juveniles’ responses to oxytocin (OT) and arginine‐vasopressin (AVP) manipulations. We quantified the expression of father–daughter bond‐related behaviors in females (n = 10) and gave acute intranasal treatments of saline, low/medium/high OT, low/high AVP, or an OT receptor antagonist (OTA) to subjects prior to a parent preference test. While females spent more time in proximity to their parents than strangers, we found a large degree of individual variation. Females with greater expression of bonding behaviors responded to OT treatments in a dose‐dependent manner. Subjects also spent less time in proximity to strangers when treated with High OT (p = 0.003) and Low OT (p = 0.007), but more time when treated with High AVP (p = 0.007), Low AVP (p = 0.009), and OTA (p = 0.001). Findings from the present study suggest that variation in the expression of bond‐related behaviors may alter responsiveness to OT and AVP, increasing engagement with unfamiliar social others. This enhanced sociality with strangers may promote the formation of pair bonds with partners.
Subgingival biofilm microbiome in individuals with asthma and periodontitis: Metagenomic analysis
Authors: Pinto Giselle R. , Carvalho Filho Paulo C. , Carvalho Rodrigo D. O. , Conceição Rogério R. , Fortuna Vitor , Gomes‐Filho Isaac S. , Trindade Soraya C. , Sarmento Viviane A.
Published: March 2024

Objective

This observational study aimed to explore the metagenomics of subgingival biofilms in individuals with varying degrees of asthma, from severe to none, to elucidate the association between the subgingival microbiome and asthma.

Materials and Methods

Subgingival biofilm samples were collected from thirty participants at the Asthma Control Program Outpatient Clinic in Bahia (ProAR). These samples were categorized into six groups based on the severity of asthma and the presence or absence of periodontitis. We employed next‐generation sequencing (Illumina MiSeq), targeting the 16S rRNA gene, to characterize the microbial communities present. Our analysis included descriptive statistics and sequencing data, evaluated using multivariate statistical methods such as the Shannon index, principal coordinate analysis, and the Bray–Curtis dissimilarity.

Results

Our findings indicate a higher prevalence of periodontally detrimental bacterial genera in individuals with severe asthma and periodontitis. Additionally, individuals with asthma, but without periodontitis, exhibited a tendency toward dysbiosis, particularly in cases of severe asthma.

Conclusion

This research provides new insights into the composition of the subgingival microbiome in individuals with varying severities of asthma and periodontitis. The genera identified in this study underscore the need for further investigations to build upon these findings.
IRE1α inhibits osteogenic differentiation of mouse embryonic fibroblasts by limiting Shh signaling
Authors: Zhang Zhixiang , Zhang Xuan , Wei Xiangzhen , Yu Chengbo , Xiao Li , Liu Jianmiao , Liu Yong , Cao Yingguang , Song Ke
Published: March 2024

Objectives

This study aimed to investigate the effect of endoplasmic reticulum (ER) stress sensor inositol‐requiring enzyme 1α (IRE1α) on the sonic hedgehog N‐terminus (N‐Shh)‐enhanced‐osteogenic differentiation process in mouse embryonic fibroblasts (MEFs).

Materials and Methods

Osteogenesis of MEFs was observed by alkaline phosphatase (ALP) staining, alizarin red staining, and Von Kossa staining assays. Activation of unfolded protein response and Shh signaling were examined using real‐time quantitative PCR and western blot assays. IRE1α‐deficient MEFs were used to explore the effect of IRE1α on N‐Shh‐driven osteogenesis.

Results

N‐Shh increased ALP activity, matrix mineralization, and the expression of Alp and Col‐I in MEFs under osteogenic conditions; notably, this was reversed when combined with the ER stress activator Tm treatment. Interestingly, the administration of N‐Shh decreased the expression of IRE1α. Abrogation of IRE1α increased the expression of Shh pathway factors in osteogenesis‐induced MEFs, contributing to the osteogenic effect of N‐Shh. Moreover, IRE1α‐deficient MEFs exhibited elevated levels of osteogenic markers.

Conclusions

Our findings suggest that the IRE1α‐mediated unfolded protein response may alleviate the ossification of MEFs by attenuating Shh signaling. Our research has identified a strategy to inhibit excessive ossification, which may have clinical significance in preventing temporomandibular joint bony ankylosis.
Topical antibiotics limit depigmentation in a mouse model of vitiligo
Authors: Touni Ahmed Ahmed , Sohn Rachel , Cosgrove Cormac , Shivde Rohan S. , Dellacecca Emilia R. , Abdel‐Aziz Rasha T. A. , Cedercreutz Kettil , Green Stefan J. , Abdel‐Wahab Hossam , Le Poole I. Caroline
Published: March 2024

Oral neomycin administration impacts the gut microbiome and delays vitiligo development in mice, and topical antibiotics may likewise allow the microbiome to preserve skin health and delay depigmentation. Here, we examined the effects of 6‐week topical antibiotic treatment on vitiligo‐prone pmel‐1 mice. Bacitracin, Neosporin, or Vaseline were applied to one denuded flank, while the contralateral flank was treated with Vaseline in all mice. Ventral depigmentation was quantified weekly. We found that topical Neosporin treatment significantly reduced depigmentation and exhibited effects beyond the treated area, while Bacitracin ointment had no effect. Stool samples collected from four representative mice/group during treatment revealed that Neosporin treatment aligned with reduced abundance of the Alistipes genus in the gut, while relevant changes to the skin microbiome at end point were less apparent. Either antibiotic treatment led to reduced expression of MR1, potentially limiting mucosal‐associated invariant T‐cell activation, while Neosporin‐treated skin selectively revealed significantly reduced CD8+ T‐cell abundance. The latter finding aligned with reduced expression of multiple inflammatory markers and markedly increased regulatory T‐cell density. Our studies on favorable skin and oral antibiotic treatment share the neomycin compound, and in either case, microbial changes were most apparent in stool samples. Taken together, neomycin‐containing antibiotic applications can mediate skin Treg infiltration to limit vitiligo development. Our study highlights the therapeutic potential of short‐term antibiotic applications to limit depigmentation vitiligo.
Forb stability, dwarf shrub stability and species asynchrony regulate ecosystem stability along an experimental precipitation gradient in a semi‐arid desert grassland
Authors: Zhang L. , Gao J. , Zhao R. , Wang J. , Hao L. , Wang M.
Published: March 2024

Precipitation pattern changes may affect plant biodiversity, which could impact ecosystem stability. However, the effects of changes in precipitation regime on ecosystem stability and their potential mechanisms are still unclear.

We conducted a 3‐year field manipulation experiment with five precipitation treatments (−40%, −20%, 0% (CK), +20% and +40% of ambient growing season precipitation) in a semi‐arid desert grassland to examine the effects of precipitation alterations on functional group stability, species asynchrony, and diversity, and the underlying mchanisms of ecosystem stability using structural equation modelling.

Alterations in precipitation had different effects on community biomass and functional group biomass. Moreover, ecosystem stability was mainly driven by forb stability (path coefficient = 0.79). Changes in precipitation had significant effects on soil dissolved inorganic N (P < 0.01) further affecting ecosystem stability through species asynchrony (path coefficient = 0.25). Dwarf shrubs had a stabilizing effect on ecosystem stability (path coefficient = 0.32), mainly via deep roots. Ecosystem stability tended to be lower in the −40% (4.72) and +40% (2.74) precipitation treatments. The common reduction in species asynchrony and stability of forb and dwarf shrub functional groups resulted in lower ecosystem stability under the −40% treatment. The lower stability under the +40% treatment might be ascribed to unimproved dwarf shrub stability. Higher dwarf shrub and forb stability contributed to higher ecosystem stability under normal precipitation changes (±20% treatments) and CK. Species diversity was not a crucial driver of ecosystem stability.

Our results indicate that precipitation alteration can regulate ecosystem stability via functional group stability (e.g. forb stability, dwarf shrub stability) and species asynchrony in a semiarid desert grassland.
A comprehensive approach for evaluating salinity stress tolerance in brinjal (Solanum melongena L.) germplasm using membership function value
Authors: Gyanagoudar Harsha Shekarappa , Hatiya Singh Tejavathu , Guhey Arti , Dharmappa Prathibha Machagondanahalli , Seetharamaiah Shivashankara Kodthalu
Published: March 2024

Salinity is a major stress factor affecting plant growth and development, which limits the productivity of vegetable crops. Brinjal (Solanum melongena L.), an important vegetable cultivated across the globe is susceptible to salinity stress. In the present study, the salinity tolerance response of 110 brinjal germplasm lines was evaluated at the germination stage using the membership function value (MFV). The MFV is a comprehensive index that integrates salt‐tolerance indices of germination parameters. The brinjal germplasms were classified into highly salt‐tolerant (>0.79), salt‐tolerant (0.79–0.65), moderately salt‐tolerant (0.64–0.21), salt‐sensitive (0.20–0.07), and highly salt‐sensitive (<0.07) based on their mean MFV. Among all the traits examined, germination percentage (0.874) and vigour index‐I (0.808) were the most reliable traits for assessing salinity tolerance, showing a higher correlation with mean MFV. Furthermore, a comprehensive mathematical model was developed for evaluating the salt‐tolerance of the brinjal germplasm. We validated our model by evaluating the brinjal germplasm at the seedling stage through a hydroponic experiment, and a strong positive correlation was observed between growth parameters at the germination and seedling stages. Salt‐tolerant genotypes showed higher chlorophyll content, photosynthetic performance and biomass accumulation with lower canopy temperature (1.57°C) under salinity compared to susceptible genotypes (2.62°C). These findings provide valuable insights into the salinity tolerance of the brinjal germplasm, and identified potential candidates to elucidate the molecular mechanisms and develop salinity‐tolerant cultivars. To our knowledge, this is the first report using a mathematical model based on MFV to evaluate the salt‐tolerance of any vegetable crop.
MiCOL6, MiCOL7A and MiCOL7B isolated from mango regulate flowering and stress response in transgenic Arabidopsis
Authors: Liu Yuan , Luo Cong , Lan Moying , Guo Yihang , Li Ruoyan , Liang Rongzhen , Chen Shuquan , Zhong Junjie , Li Baijun , Xie Fangfang , Chen Canbin , He Xinhua
Published: March 2024

The CONSTANS/CONSTANS‐Like (CO/COL) family has been shown to play important roles in flowering, stress tolerance, fruit development and ripening in higher plants. In this study, three COL genes, MiCOL6, MiCOL7A and MiCOL7B, which each contain only one CCT domain, were isolated from mango (Mangifera indica), and their functions were investigated. MiCOL7A and MiCOL7B were expressed mainly at 20 days after flowering (DAF), and all three genes were highly expressed during the flowering induction period. The expression levels of the three genes were affected by light conditions, but only MiCOL6 exhibited a clear circadian rhythm. Overexpression of MiCOL6 promoted earlier flowering, while overexpression of MiCOL7A or MiCOL7B delayed flowering compared to that in the control lines of Arabidopsis thaliana under long‐day (LD) and short‐day (SD) conditions. Overexpressing MiCOL6, MiCOL7A or MiCOL7B in transgenic plants increased superoxide dismutase (SOD) and proline levels, decreased malondialdehyde (MAD) levels, and improved survival under drought and salt stress. In addition, yeast two‐hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) analyses showed that the MiCOL6, MiCOL7A and MiCOL7B proteins interact with several stress‐ and flower‐related proteins. This work demonstrates the functions of MiCOL6, MiCOL7A and MiCOL7B and provides a foundation for further research on the role of mango COL genes in flowering regulation and the abiotic stress response.
Translation and validation of ageism scale for dental students into Malay language
Authors: Yong Tee Yee , Zhen Chen Yik , John Jacob , Danaee Mahmoud , Marchini Leonardo
Published: March 2024

Aims

Identifying ageism among dental students is essential in gerodontology courses. This study aimed to perform a preliminary validation of a Malay version of the ageism scale for dental students (ASDS‐My).

Methods and Results

The 27‐item ASDS were translated into Malay language and completed by 168 dental students. Exploratory factor analysis (EFA) with Promax rotation, Polychoric Correlation Matrix and Principal Axis Factoring was conducted. Internal consistency reliability and discriminative validity were analysed. Criterion validity was measured by comparing ASDS‐My with Fraboni Scale of Ageism (FSA). A Kaiser–Meyer–Olkin of 0.612 and a Bartlett's Test of Sphericity yielding p < .001 confirmed the adequate factorability. EFA revealed a 15‐items scale distributed into five‐factors explaining 54.5% of overall variance, with acceptable reliability. The two factors involved cost‐benefit of dental treatment on older patients and challenges during medical history taking. The third, fourth and fifth factors explained attitude towards older patients, negative views of older patients and exposure of dental students to Gerodontology training and experiences respectively. Most factors were significantly positively related to FSA. Discriminative validity revealed significant differences for gender, place of stay and year of study.

Conclusion

Preliminary validation of the ASDS‐My produced a five‐factors 15‐items scale with acceptable validity and reliability.
A characterization for the defect of rank one valued field extensions
Authors: Novacoski Josnei
Published: March 2024

In this paper, we present a characterization for the defect of a simple algebraic extension of rank one valued fields using the key polynomials that define the valuation. As a particular example, this gives the classification of defect extensions of degree as dependent or independent presented by Kuhlmann.
Brecha de género en pensiones en 23 ciudades de Colombia y sus áreas metropolitanas: análisis sobre la encuesta de hogares 2008-2019
Authors: Estrada Trujillo Victoria Eugenia , Astorquiza Bustos Bilver Adrian
Published: March 2024

Una primera expresión de desigualdad de género en pensiones la constituye la falta de información sistemática y diferenciada por género sobre cobertura de afiliación y beneficio pensional. Esto limita el análisis de los avances en seguridad social de las mujeres en la vejez y en las metas de equidad de género. En Colombia, pocos estudios analizan la brecha de género en pensiones; el objetivo del presente artículo fue analizar esta brecha, utilizando indicadores de cobertura de afiliación y beneficio pensional con información de la Gran Encuesta Integrada de Hogares en el periodo 2008-2019. Resultados: la brecha de género en la tasa de afiliación al sistema pensional se expresa en una diferencia de 5,2 puntos porcentuales en 2008, con tendencia al incremento, llegando a 6 puntos porcentuales en 2019. La brecha en la tasa de beneficio pensional se manifiesta en una diferencia de más de 27 puntos porcentuales para 2008, reduciéndose a 24,7 puntos porcentuales para 2019, reducción que se da a expensas de un descenso más pronunciado de la tasa de los hombres. Conclusión: la brecha de género en la tasa de beneficiarios de pensiones sugiere una baja cobertura de acceso de las mujeres a la seguridad social en la vejez y evidencia la desigualdad estructural de género en pensiones. La brecha de género en la tasa de afiliación, documentada en este estudio, permite prever un futuro no favorable, tanto para hombres como para mujeres, en el acceso a la pensión, situación más dramática para las mujeres.
Mapeamento temático e tendências conceituais dos estudos sobre a participação social em saúde na América
Authors: Viana Machado Frederico , Rech Carla Michele , Silveira Pinto Rodrigo , Romão Wagner de Melo , Maria Marques Matias Manuelle , Freitas Gabriele Carvalho de , Kujawa Henrique
Published: March 2024

RESUMO: Introdução/objetivos: Este trabalho mapeia os termos e conceitos mais utilizados em artigos sobre participação em saúde buscando identificar seu tratamento ao longo do tempo, bem como a relação, a organização e a distribuição temporal das conexões temáticas e áreas de conhecimento, considerando a diversidade de temas e conceitos presentes na literatura nas Américas. Metodologia: Foi realizada uma análise bibliométrica de artigos em inglês, espanhol e português, extraídos de buscas na BVS, Pubmed, SCOPUS, WOS e SciELO, consolidando uma base de dados com 641 referências. Com o uso do VOSViewer aplicamos a análise de coocorrência de palavras baseada em dados de texto (título e resumo) e coocorrência de palavras-chave. Resultados: Foram mapeadas duas grandes abordagens para a participação, uma mais relacionada à comunidade e outra às instituições políticas públicas. A análise temporal pode identificar a evolução e a frequência da utilização de conceitos, métodos e temas nas últimas décadas. Conclusões: O desenvolvimento histórico, o acúmulo de produções e a diversificação do campo coincidem com uma maior especificidade conceitual e a formação de consensos teórico. Os descritores metodológicos indicam a hegemonia das abordagens qualitativas, e a consolidação da participação em saúde como um objeto de investigação científica, um método de produção de conhecimento e uma ferramenta capaz de contribuir para a gestão e o aprimoramento das políticas públicas.

PALAVRAS-CHAVE: Bibliometria; Saúde Pública; Participação em Saúde; Engajamento Comunitário;
In Situ Measurement of Oil Reservoir and Oil Layers by Fluorescence Technique in a Ball-on-Disc Test Rig
Authors: Liang He , Li Chuang , Wang Wenzhong , Guo Yulong
Published: March 2024

The major oil supply for the ball-on-disc contact is provided by the lubricating oil reservoir and the oil ridges; however, the regularity of their changes has not been thoroughly investigated. In this study, the laser-induced fluorescence technique was adopted to determine the film distribution of the oil reservoir and the layer thickness of the oil ridges on the free surface. It clearly depicts the changes in the oil reservoir and reveals the mechanism of the oil reflow surrounding the contact region under various driving actions. The results may give a new perspective and a fuller understanding of the lubricating oil supply by revealing additional information about the oil supply surrounding the contact region.
Study on Fretting Wear Properties of GCr15 Steel Via Ultrasonic Surface Rolling Process
Authors: Sun Xinhua , Xia Dianxiu , Zhang Mingyuan , Wang Shouren , Zhang Yunhe , Cai Yuquan , Si Guyi , Li Shuqi , Zhang Xintao , Zhang Jian
Published: March 2024

Ultrasonic surface rolling (USR) was applied to GCr15 steel with different static loads and passes to improve the friction and wear properties, and then the fretting wear mechanism of GCr15 steel after USR treatment was systematically investigated. The results showed that the specimens treated by the USR had lower surface roughness and significantly increased compressive residual stress and microhardness. Furthermore, severe plastic deformation occurred in the surface layer of the specimen, which refined the grains and increased the density of high- and low-angle grain boundaries. Besides, the results of the fretting test showed that the USR treated specimens had lower wear volume, dissipated energy, and steady-state friction coefficient. The fretting wear resistance increased with the static load and the number of passes. The fretting wear mechanism changed from abrasive wear and severe adhesive wear to slight fatigue wear and abrasive wear owing to the use of the USR treatment. Surface smoothing and hardening are responsible for the improvement in the fretting wear properties of GCr15 steel for USR treatment.
Propagation of Uncertainty in Experimental Dynamic Coefficients of Fluid Film Journal Bearings
Authors: Herrera Pedro , Goyne Christopher , Rockwell Robert
Published: March 2024

The stiffness and damping coefficients of fluid film bearings play a key role in predicting levels of vibration and stability margins in high-performance industrial rotating machinery. However, variability in the coefficients calculated by numerical bearing codes creates inaccuracies in the rotodynamic predictions. Therefore, there is a strong need for accurate experimental measurement of bearing coefficients for validation purposes. This work examines new propagation uncertainty strategies in bearing coefficients estimation, and for the first time examines the effect of the nonlinearity of the dynamic coefficients on the experimental uncertainty estimated by the Taylor Series Method. The Montecarlo method is presented as a more accurate approach to estimating experimental uncertainty. The results of the analyses are compared to published values from previously reported studies. This paper also proposes a novel method to convert the random behavior in the output of a sensor in the time domain to the frequency domain. It is found this conversion is quite beneficial for the accuracy of the coefficients; in one example, uncertainty estimations of ±84% are reduced to just ±6%, when using the proposed method. This work also reveals that the uncertainty estimations from the Taylor Series Method are not entirely reliable, without additional checks of nonlinearity, and that converting data to the frequency domain, by using the novel method here, is useful for achieving smaller uncertainty estimations than with traditional methodology.
Combining range-general and range-specific techniques for late-time focused image reconstruction
Authors: Dalton Kyle S. , Brown Daniel C. , Blanford Thomas E.
Published: March 2024

Synthetic aperture sonar (SAS) is an acoustic method for detecting objects in an environment. Conventional SAS image reconstruction techniques invert a forward model based on geometric scattering and straight-line propagation. Acoustic features that do not fit this model, such as multiple scattering and late-time returns, appear out of focus. This paper describes an image reconstruction technique that selectively applies range-general and range-specific methods to improve the focus of late-time returns while maintaining image quality away from the focal plane. The technique is demonstrated on experimental data and compared with a range-specific algorithm.
A unified beamforming and source separation model for static and dynamic human-robot interaction
Authors: Wuth Jorge , Mahu Rodrigo , Cohen Israel , Stern Richard M. , Yoma Néstor Becerra
Published: March 2024

This paper presents a unified model for combining beamforming and blind source separation (BSS). The validity of the model's assumptions is confirmed by recovering target speech information in noise accurately using Oracle information. Using real static human-robot interaction (HRI) data, the proposed combination of BSS with the minimum-variance distortionless response beamformer provides a greater signal-to-noise ratio (SNR) than previous parallel and cascade systems that combine BSS and beamforming. In the difficult-to-model HRI dynamic environment, the system provides a SNR gain that was 2.8 dB greater than the results obtained with the cascade combination, where the parallel combination is infeasible.
Closing the gap: Oxford Nanopore Technologies R10 sequencing allows comparable results to Illumina sequencing for SNP-based outbreak investigation of bacterial pathogens
Authors: Bogaerts Bert , Van den Bossche An , Verhaegen Bavo , Delbrassinne Laurence , Mattheus Wesley , Nouws Stéphanie , Godfroid Maxime , Hoffman Stefan , Roosens Nancy H. C. , De Keersmaecker Sigrid C. J. , Vanneste Kevin
Published: March 2024

Whole-genome sequencing has become the method of choice for bacterial outbreak investigation, with most clinical and public health laboratories currently routinely using short-read Illumina sequencing. Recently, long-read Oxford Nanopore Technologies (ONT) sequencing has gained prominence and may offer advantages over short-read sequencing, particularly with the recent introduction of the R10 chemistry, which promises much lower error rates than the R9 chemistry. However, limited information is available on its performance for bacterial single-nucleotide polymorphism (SNP)-based outbreak investigation. We present an open-source workflow, Prokaryotic Awesome variant Calling Utility (PACU) (
https://github.com/BioinformaticsPlatformWIV-ISP/PACU
), for constructing SNP phylogenies using Illumina and/or ONT R9/R10 sequencing data. The workflow was evaluated using outbreak data sets of Shiga toxin-producing
Escherichia coli
and
Listeria monocytogenes
by comparing ONT R9 and R10 with Illumina data. The performance of each sequencing technology was evaluated not only separately but also by integrating samples sequenced by different technologies/chemistries into the same phylogenomic analysis. Additionally, the minimum sequencing time required to obtain accurate phylogenetic results using nanopore sequencing was evaluated. PACU allowed accurate identification of outbreak clusters for both species using all technologies/chemistries, but ONT R9 results deviated slightly more from the Illumina results. ONT R10 results showed trends very similar to Illumina, and we found that integrating data sets sequenced by either Illumina or ONT R10 for different isolates into the same analysis produced stable and highly accurate phylogenomic results. The resulting phylogenies for these two outbreaks stabilized after ~20 hours of sequencing for ONT R9 and ~8 hours for ONT R10. This study provides a proof of concept for using ONT R10, either in isolation or in combination with Illumina, for rapid and accurate bacterial SNP-based outbreak investigation.
Comparative transcriptional analysis of
Candida auris
biofilms following farnesol and tyrosol treatment
Authors: Jakab Ágnes , Kovács Fruzsina , Balla Noémi , Nagy-Köteles Csaba , Ragyák Ágota , Nagy Fruzsina , Borman Andrew M. , Majoros László , Kovács Renátó
Published: March 2024

Candida auris
is frequently associated with biofilm-related invasive infections. The resistant profile of these biofilms necessitates innovative therapeutic options, where quorum sensing may be a potential target. Farnesol and tyrosol are two fungal quorum-sensing molecules with antifungal effects at supraphysiological concentrations. Here, we performed genome-wide transcript profiling with
C. auris
biofilms following farnesol or tyrosol exposure using transcriptome sequencing (RNA-Seq). Since transition metals play a central role in fungal virulence and biofilm formation, levels of intracellular calcium, magnesium, and iron were determined following farnesol or tyrosol treatment using inductively coupled plasma optical emission spectrometry. Farnesol caused an 89.9% and 73.8% significant reduction in the calcium and magnesium content, respectively, whereas tyrosol resulted in 82.6%, 76.6%, and 81.2% decrease in the calcium, magnesium, and iron content, respectively, compared to the control. Genes involved in biofilm events, glycolysis, ergosterol biosynthesis, fatty acid oxidation, iron metabolism, and autophagy were primarily affected in treated cells. To prove ergosterol quorum-sensing molecule interactions, microdilution-based susceptibility testing was performed, where the complexation of farnesol, but not tyrosol, with ergosterol was impeded in the presence of exogenous ergosterol, resulting in a minimum inhibitory concentration increase in the quorum-sensing molecules. This study revealed several farnesol- and tyrosol-specific responses, which will contribute to the development of alternative therapies against
C. auris
biofilms.

IMPORTANCE

Candida auris
is a multidrug-resistant fungal pathogen, which is frequently associated with biofilm-related infections.
Candida
-derived quorum-sensing molecules (farnesol and tyrosol) play a pivotal role in the regulation of fungal morphogenesis and biofilm development. Furthermore, they may have remarkable anti-biofilm effects, especially at supraphysiological concentrations. Innovative therapeutic approaches interfering with quorum sensing may be a promising future strategy against
C. auris
biofilms; however, limited data are currently available concerning farnesol-induced and tyrosol-related molecular effects in
C. auris
. Here, we detected several genes involved in biofilm events, glycolysis, ergosterol biosynthesis, fatty acid oxidation, iron metabolism, and autophagy, which were primarily influenced following farnesol or tyrosol exposure. Moreover, calcium, magnesium, and iron homeostasis were also significantly affected. These results reveal those molecular and physiological events, which may support the development of novel therapeutic approaches against
C. auris
biofilms.
Escherichia coli
possessing the dihydroxyacetone phosphate shunt utilize 5′-deoxynucleosides for growth
Authors: Huening Katherine A. , Groves Joshua T. , Wildenthal John A. , Tabita F. Robert , North Justin A.
Published: March 2024

All organisms utilize
S
-adenosyl-
l-
methionine (SAM) as a key co-substrate for the methylation of biological molecules, the synthesis of polyamines, and radical SAM reactions. When these processes occur, 5′-deoxy-nucleosides are formed as byproducts such as
S
-adenosyl-
l
-homocysteine, 5′-methylthioadenosine (MTA), and 5′-deoxyadenosine (5dAdo). A prevalent pathway found in bacteria for the metabolism of MTA and 5dAdo is the dihydroxyacetone phosphate (DHAP) shunt, which converts these compounds into dihydroxyacetone phosphate and 2-methylthioacetaldehyde or acetaldehyde, respectively. Previous work in other organisms has shown that the DHAP shunt can enable methionine synthesis from MTA or serve as an MTA and 5dAdo detoxification pathway. Rather, the DHAP shunt in
Escherichia coli
ATCC 25922, when introduced into
E. coli
K-12, enables the use of 5dAdo and MTA as a carbon source for growth. When MTA is the substrate, the sulfur component is not significantly recycled back to methionine but rather accumulates as 2-methylthioethanol, which is slowly oxidized non-enzymatically under aerobic conditions. The DHAP shunt in ATCC 25922 is active under oxic and anoxic conditions. Growth using 5-deoxy-
d
-ribose was observed during aerobic respiration and anaerobic respiration with Trimethylamine N-oxide (TMAO), but not during fermentation or respiration with nitrate. This suggests the DHAP shunt may only be relevant for extraintestinal pathogenic
E. coli
lineages with the DHAP shunt that inhabit oxic or TMAO-rich extraintestinal environments. This reveals a heretofore overlooked role of the DHAP shunt in carbon and energy metabolism from ubiquitous SAM utilization byproducts and suggests a similar role may occur in other pathogenic and non-pathogenic bacteria with the DHAP shunt.

IMPORTANCE

The acquisition and utilization of organic compounds that serve as growth substrates are essential for
Escherichia coli
to grow and multiply. Ubiquitous enzymatic reactions involving S-adenosyl-
l
-methionine as a co-substrate by all organisms result in the formation of the 5′-deoxy-nucleoside byproducts, 5′-methylthioadenosine and 5′-deoxyadenosine. All
E. coli
possess a conserved nucleosidase that cleaves these 5′-deoxy-nucleosides into 5-deoxy-pentose sugars for adenine salvage. The DHAP shunt pathway is found in some extraintestinal pathogenic
E. coli
, but its function in
E. coli
possessing it has remained unknown. This study reveals that the DHAP shunt enables the utilization of 5′-deoxy-nucleosides and 5-deoxy-pentose sugars as growth substrates in
E. coli
strains with the pathway during aerobic respiration and anaerobic respiration with TMAO, but not fermentative growth. This provides an insight into the diversity of sugar compounds accessible by
E. coli
with the DHAP shunt and suggests that the DHAP shunt is primarily relevant in oxic or TMAO-rich extraintestinal environments.
Whole-genome sequencing-based antimicrobial resistance and shedding dynamics of
Escherichia coli
isolated from calves before and after antimicrobial group treatments
Authors: Bernier Gosselin Véronique , Fernandez Javier E. , Ollagnier Catherine , Morel Isabelle , Siegenthaler Raphael , Collaud Alexandra , Meylan Mireille , Perreten Vincent
Published: March 2024

The fattening of calves is often associated with high antimicrobial use and the selection of antimicrobial resistance (AMR). The objective of this observational longitudinal study was to describe the AMR and strain dynamics, using whole-genome sequencing (WGS), of fecal
Escherichia coli
in a cohort of 22 calves. All calves received antimicrobial group treatments on Day (D) 1 (oxytetracycline, intramuscularly) and on D4 through D12 (doxycycline, in-feed). Additionally, eight calves received individual parenteral treatments between D7 and D59, including florfenicol, amoxicillin, marbofloxacin, and gamithromycin. Rectal swabs were collected from all calves on D1 (prior to treatment), D2, D9, and D82. The swabs were spread onto
Enterobacterales
-selective agar, and three
E. coli
colonies per plate were subjected to WGS. Out of 264 isolates across all calves and sampling times, 80 unique strains were identified, a majority of which harbored genes conferring resistance to tetracyclines, streptomycin, and sulfonamides. The diversity of strains decreased during the in-feed antimicrobial group treatment of the calves. On D82, 90% of isolates were strains that were not isolated at previous sampling times, and the median number per strain of AMR determinants to tetracyclines, florfenicol, β-lactams, quinolones, or macrolides decreased compared to D9. Additionally, clonal dissemination of some strains represented the main transmission route of AMR determinants. In this study, WGS revealed important variations in strain diversity and genotypic AMR of fecal
E. coli
over time in calves subjected to group antimicrobial treatments.

IMPORTANCE

The continued emergence and spread of antimicrobial resistance (AMR) determinants are serious global concerns. The dynamics of AMR spread and persistence in bacterial and animal host populations are complex and not solely driven by antimicrobial selection pressure. In calf fattening, both antimicrobial use and carriage prevalence of antimicrobial-resistant bacteria are generally recognized as high. This study provides new insights into the short-term, within-farm dynamics and transmission of AMR determinants in
Escherichia coli
from the dominant fecal flora of calves subjected to antimicrobial group treatments during the rearing period. The diversity of
E. coli
strains decreased over time, although, in contrast to previous observations in extended-spectrum β-lactamase-producing
Enterobacterales
, the predominance of a few clones was not observed. The spread of AMR determinants occurred through the dissemination of clonal strains among calves. The median number per strain of AMR determinants conferring resistance to selected antimicrobials decreased toward the end of the rearing period.
Divergent mitochondrial responses and metabolic signal pathways secure the azole resistance in Crabtree-positive and negative
Candida
species
Authors: Zhou Meng , Peng Jingwen , Ren Kun , Yu Yu , Li Dongmei , She Xiaodong , Liu Weida
Published: March 2024

Azole drugs are the main therapeutic drugs for invasive fungal infections. However, azole-resistant strains appear repeatedly in the environment, posing a major threat to human health. Several reports have shown that mitochondria are associated with the virulence of pathogenic fungi. However, there are few studies on the mechanisms of mitochondria-mediated azoles resistance. Here, we first performed mitochondrial proteomic analysis on multiple
Candida
species (
Candida albicans
,
Nakaseomyces glabrata
,
Pichia kudriavzevii,
and
Candida auris
) and analyzed the differentially expressed mitochondrial proteins (DEMPs) between azole-sensitive and azole-resistant
Candida
species. Subsequently, we performed Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, gene ontology analysis, and protein-protein interaction network analysis of DEMPs. Our results showed that a total of 417, 165, and 25 DEMPs were identified in resistant
C. albicans
,
N. glabrata,
and
C. auris
, respectively. These DEMPs were enriched in ribosomal biogenesis at cytosol and mitochondria, tricarboxylic acid cycle, glycolysis, transporters, ergosterol, and cell wall mannan biosynthesis. The high activations of these cellular activities, found in
C. albicans
and
C. auris
(at low scale), were mostly opposite to those observed in two fermenter species—
N. glabrata
and
P. kudriavzevii
. Several transcription factors including Rtg3 were highly produced in resistant
C. albicans
that experienced a complex I activation of mitochondrial electron transport chain (ETC). The reduction of mitochondrial-related activities and complex IV/V of ETC in
N. glabrata
and
P. kudriavzevii
was companying with the reduced proteins of Tor1, Hog1, and Snf1/Snf4.

IMPORTANCE

Candida
spp. are common organisms that cause a variety of invasive diseases. However,
Candida
spp. are resistant to azoles, which hinders antifungal therapy. Exploring the drug-resistance mechanism of pathogenic
Candida
spp. will help improve the prevention and control strategy and discover new targets. Mitochondria, as an important organelle in eukaryotic cells, are closely related to a variety of cellular activities. However, the role of mitochondrial proteins in mediating azole resistance in
Candida
spp. has not been elucidated. Here, we analyzed the mitochondrial proteins and signaling pathways that mediate azole resistance in
Candida
spp. to provide ideas and references for solving the problem of azole resistance. Our work may offer new insights into the connection between mitochondria and azoles resistance in pathogenic fungi and highlight the potential clinical value of mitochondrial proteins in the treatment of invasive fungal infections.
Comparison of the Simplexa GBS Direct and ARIES GBS assays for the detection of
S. agalactiae
in broth-enriched swab specimens
Authors: Sabharwal Lavannya , Faron Matthew L. , Buchan Blake W.
Published: March 2024

We conducted a comparative evaluation of the FDA-cleared Simplexa GBS Direct and ARIES GBS molecular assays for the detection of
Streptococcus agalactiae
(Group B
Streptococcus
, GBS) in 386 prospectively collected, broth-enriched vaginal/rectal swab specimens. The sensitivity of each test was 96.2% and specificity was ≥98.7% when compared to a combined direct and enriched culture method using chromogenic culture medium. A total of four specimens were called positive by both molecular assays but negative by culture, likely representing specimens with a low burden of GBS in these specimens. Two specimens were reported positive by culture but negative by both molecular assays. One of these specimens demonstrated atypically colored colonies on chromogenic agar; the other yielded typically colored colonies only observed after broth enrichment. Our data demonstrate equivalent performance of Simplexa and ARIES molecular assays for the detection of GBS in clinical specimens.

IMPORTANCE

Clinical laboratories often face decisions regarding which of the multiple available molecular platforms would best fit their needs based on cost, workflow, menu, and diagnostic performance. Therefore, objective clinical comparisons of similar molecular tests are valuable resources to aid these decisions. We provide a clinical comparison of two FDA-cleared tests to routine culture and to each other that can be used by clinical laboratories when determining which of the available molecular platforms would best fit their laboratory in terms of workflow, cost, and performance.
Vulvar leiomyoma in a postmenopausal woman
Authors: Redlin Tanner , Bishop Brain , Durkin Tory , Hultgren Elizabeth
Published: March 2024

Leiomyomas of the uterus are the most common benign tumours of women in the reproductive age group, affecting up to 40%–50% of women older than 35. In postmenopausal women, the incidence is much lower with an estimated incidence of 1%–2% in women in the 60–80 years old age group. Vulvar leiomyomas are much rarer than their uterine counterparts, accounting for only 0.03% of all gynaecological neoplasms and 0.07% of all vulvar tumours. These tumours are well-circumscribed, painless, solitary growths that affect females of all ages. Given the presentation and rarity of vulvar leiomyomas, they are often misdiagnosed as a Bartholin gland cyst, abscess or even cancer preoperatively. We present a case of a woman in her 70s with a 1.5 cm firm mass that was palpated on the left lower vaginal side wall and was initially suspected to be a Bartholin gland cyst or abscess. Initial treatment included antibiotics and an incision and drainage. Two weeks later, the mass had grown to 3 cm in size. Wide excisional biopsy revealed the mass to be a vulvar leiomyoma.
High imperforate transverse vaginal septum with vaginal cicatrisation: a surgical tribulation
Authors: Shetty Jyothi , Pandey Deeksha , Reddy Deepa
Published: March 2024

An early adolescent girl was referred to us with cryptomenorrhoea, and pelvic pain consistent with obstructed menstruation. Originally presumed to be a case of imperforate hymen, she was referred to our centre after two failed surgical misadventures at correcting the obstruction. MRI revealed a haematometrocolpos, high transverse complete vaginal septum and an occluded vagina. She underwent a laparoscopic drainage of the collection, septal resection and a vaginoplasty with an absorbable Interceed graft. Postoperative recovery was smooth and she was sent with instructions to use a vaginal mould daily. Successful surgical treatment requires precise preoperative planning with MRI. A vaginal-assisted laparoscopic approach turned out to be advantageous in resecting the septum to a large extent due to the associated cicatrised vagina. The use of Interceed, a novel mould and harnessing system, ensured a favourable postoperative outcome by bolstering patient motivation due to its less challenging technique of use.
Bronchogenic cyst: a rare cause of palpitations and atrial fibrillation
Authors: Khan Zahid , Batchelor Tim , Rees Paul
Published: March 2024

Bronchogenic cysts are rare congenital lesions found primarily in the mediastinum. Most patients are asymptomatic and can be treated with minimally invasive resection. We present a case of a middle-aged patient who presented to a district general hospital with palpitations and shortness of breath. She underwent a computerised tomographic pulmonary angiogram that showed a likely bronchogenic cyst and was subsequently transferred to our hospital. She developed atrial fibrillation during admission requiring therapy with beta-blockers and digoxin. Cardiac MRI revealed a large cyst posterior to the left atrium, a moderate circumferential pericardial effusion and bilateral pleural effusions. There was significant left atrial compression. The patient underwent surgical removal of the cyst and was discharged. She returned to the hospital within a week with palpitations and was treated with intravenous antibiotics for sepsis. She was discharged a week later and remained clinically stable.
Wings of Healing: regulatory landscape, case studies and the Indian prologue of drones in healthcare
Authors: Sharma Ankita , Vijayan Anju , Ananth Pavan , Chhetri Deepshikha , Konapur Rahul , Gudi Nachiket
Published: March 2024

The healthcare sector is among the most rapidly expanding sectors. Drones are increasingly being used to reach the unreached in healthcare. Drones exhibit profound significance by overcoming accessibility challenges and offering versatile solutions. The future of healthcare is in the air, and new government initiatives uncover the country’s rapid market growth. Investments in drone technologies are rising, with research predicting significant drone expansion in the upcoming decade. Since this sector is still in its nascent stage, the time is ripe for stakeholders to collectively work for the effective implementation of drone technology in India. In this context, the paper seeks to bridge existing knowledge gaps by analysing the global regulatory landscape, the evolution of drones in India, used cases in healthcare, and the barriers that constrain their deployment in the healthcare domain. It explores the obstacles that hinder the widespread adoption of drones. Addressing these challenges becomes essential in unlocking the full potential of drone technology in revolutionising healthcare delivery, enhancing patient outcomes and overcoming logistical constraints. The report argues about the potential shift drones can bring to healthcare delivery while underlining the necessity of addressing regulatory concerns and fostering public trust.