bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of wholemount dissection methods for neuronal subtype marker expression in the mouse myenteric plexus
Authors: Gomez‐Frittelli Julieta , Hamnett Ryan , Kaltschmidt Julia A.
Published: October 2023

Background

Accurately reporting the identity and representation of enteric nervous system (ENS) neuronal subtypes along the length of the gastrointestinal (GI) tract is critical to advancing our understanding of ENS control of GI function. Reports of varying proportions of subtype marker expression have employed different dissection techniques to achieve wholemount muscularis preparations of myenteric plexus. In this study, we asked whether differences in GI dissection methods could introduce variability into the quantification of marker expression.

Methods

We compared three commonly used methods of ENS wholemount dissection: two flat‐sheet preparations that differed in the order of microdissection and fixation and a third rod‐mounted peeling technique. We also tested a reversed orientation variation of flat‐sheet peeling, two step‐by‐step variations of the rod peeling technique, and whole‐gut fixation as a tube. We assessed marker expression using immunohistochemistry, genetic reporter lines, confocal microscopy, and automated image analysis.

Key Results and Conclusions

We found no significant differences between the two flat‐sheet preparation methods in the expression of calretinin or neuronal nitric oxide synthase (nNOS) as a proportion of total neurons in ileum myenteric plexus. However, the rod‐mounted peeling method resulted in decreased proportion of neurons labeled for both calretinin and nNOS. This method also resulted in decreased transgenic reporter fluorescent protein (tdTomato) for substance P in distal colon and choline acetyltransferase (ChAT) in both ileum and distal colon. These results suggest that labeling among some markers, both native protein and transgenic fluorescent reporters, is decreased by the rod‐mounted mechanical method of peeling. The step‐by‐step variations of this method point to mechanical manipulation of the tissue as the likely cause of decreased labeling. Our study thereby demonstrates a critical variability in wholemount muscularis dissection methods.
Prognostic Factors and Surgical Impact of Non‐metastatic Conventional Chondrosarcoma of the Extremities
Authors: Wang Wenhui , Zhen Junping
Published: October 2023

Objective

Chondrosarcoma is a common bone malignancy, and the main treatment method is surgery. Different surgeries lead to different survival outcomes. The aim of this study was to construct a new clinical predictive tool to accurately predict the overall survival (OS) and cause specific survival (CSS) of patients with chondrosarcoma receiving different treatments.

Methods

A total of 620 patients with chondrosarcoma registered between January 1, 2000 and December 31, 2016 were recruited as study targets. The missing values are filled by multiple imputation. Two continuous variables, age and tumor size, were divided into binary variables based on Kaplan–Meier curve. Univariate and multivariate analyses were used to explore predictors and establish nomograms. Propensity score matching (PSM) analysis was used to reduce the impact of potential confounders to determine whether different surgical modalities had any survival benefits in subgroups.

Results

In a multivariate cox regression, age, grade, tumor size, radiotherapy, chemotherapy, and surgical methods were identified as independent prognostic factors for chondrosarcoma. To construct 1‐, 3‐, and 5‐year nomogram maps of OS and CSS with prognostic factors and verify the c index internally (OS, 0.807; CSS, 0.847) above American Joint Committee on Cancer (AJCC) (OS, 0.685; CSS, 0.732).

Conclusion

This study found that the 5 year overall survival rate of patients with non‐metastatic chondrosarcoma of the extremities was about 80%. Age, high malignancy, large tumor, prior chemoradiotherapy, and poor surgical selection were independent risk factors. Therefore, the nomogram established in this study will help to optimize clinicians' personalized decision making for patients.
A quantitative autonomous bioluminescence reporter system with a wide dynamic range for Plant Synthetic Biology
Authors: Calvache Camilo , Vazquez‐Vilar Marta , Moreno‐Giménez Elena , Orzaez Diego
Published: October 2023

Plant Synthetic Biology aims to enhance the capacities of plants by designing and integrating synthetic gene circuits (SGCs). Quantitative reporting solutions that can produce quick, rich datasets affordably are necessary for SGC optimization. In this paper, we present a new, low‐cost, and high‐throughput reporter system for the quantitative measurement of gene expression in plants based on autonomous bioluminescence. This method eliminates the need for an exogenous supply of luciferase substrate by exploiting the entire Neonothopanus nambi fungal bioluminescence cyclic pathway to build a self‐sustained reporter. The HispS gene, the pathway's limiting step, was set up as the reporter's transcriptional entry point as part of the new system's design, which significantly improved the output's dynamic range and brought it on par with that of the gold standard FLuc/RLuc reporter. Additionally, transient ratiometric measurements in N. benthamiana were made possible by the addition of an enhanced GFP as a normalizer. The performance of new NeoLuc/eGFP system was extensively validated with SGCs previously described, including phytohormone and optogenetic sensors. Furthermore, we employed NeoLuc/eGFP in the optimization of challenging SGCs, including new configurations for an agrochemical (copper) switch, a new blue optogenetic sensor, and a dual copper/red‐light switch for tight regulation of metabolic pathways.
Neural decoding, the Atlantis machine, and zombies
Authors: Cao Rosa , Warren Jared
Published: October 2023

Neural decoding studies seem to show that the “private” experiences of others are more accessible than philosophers have traditionally believed. While these studies have many limitations, they do demonstrate that by capturing patterns in brain activity, we can discover a great deal about what a subject is experiencing. We present a thought experiment about a super‐decoder — the Atlantis machine — and argue that given plausible assumptions, an Atlantis machine could one day be built. On the basis of this argument, we then argue for the rejection of robust notions of consciousness, which have generated numerous puzzles, including puzzles about the possibility of philosophical zombies. In light of the Atlantis machine, it can be seen that robust notions of consciousness do not earn their explanatory or descriptive keep. More modest concepts of consciousness are sufficient to account for all phenomena — in both senses of the term. This kind of antirobustness about consciousness is a deflationary approach to conscious experience that differs in important ways from illusionist approaches.
Wicked policy problems and COVID‐19 in small island developing states: The cases of Mauritius and Seychelles
Authors: Kasseeah Harshana , Opp Susan
Published: October 2023

The COVID‐19 pandemic represented one of the most significant wicked policy problems in modern history. Global policy efforts to combat the pandemic reflect a diverse set of approaches, with varying underlying goals and values driving the policy choices. This article studies the pandemic response of two small island developing states, Mauritius and Seychelles, to better understand the policy landscape in this understudied African region. Evidence from these two island nations provides important insights into the opportunities and constraints faced by island developing states. Using in‐depth qualitative interviews with policy actors and reviews of official policy documents, this article studies the policy landscape of these two small island developing states. Findings from this research offer insights for scholars and practitioners interested in the intersection of wicked problems and policy.

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Dynamics of coastal tourism: drivers of spatial change in South‐East Asia
Authors: Hampton Mark P. , Bianchi Raoul , Jeyacheya Julia
Published: October 2023

Coastal tourism has grown significantly across South‐East Asia from the 1960s, particularly in three key destinations hosting large tourist numbers: Indonesia, Malaysia, and Thailand. It encompasses different scales from basic backpacker accommodation in budget enclaves to large scale capital‐intensive luxury resort enclaves. Coastal tourism studies typically range from descriptive analyses of destinations’ evolutionary dynamics and resort morphology to more granular ethnographic inspections of socio‐economic patterns of transformation and resource conflicts. More recent critical research theorizes the spatial reorganization of coastal tourism in relation to economic restructuring processes. Although national tourism policy and economic development is often analysed, forces shaping coastal tourism development have been little examined and research typically focusses on impact case studies without analysing the underlying political economy. This paper interrogates the political‐economic drivers of the historical‐geographical and spatial organization of coastal tourism in these three major destinations and demonstrates how processes of tourism capital accumulation are experienced/contested via intensified commodification leading to increasingly complex and diversified coastal tourism political economies.
Immoral, infectious, or both? How disgust sensitivity predicts judgments of violations against COVID‐19 mitigation actions
Authors: Schwarz Sascha , Klümper Lisa , Jansen Markus Thomas , Agthe Maria
Published: October 2023

Violations against mitigation actions to prevent the spreading of the SARS‐CoV‐2 virus causing COVID‐19, such as not wearing a mask or not practicing social distancing, were seen as immoral and could also increase the likelihood of spreading the virus. In two studies (N1 = 318, N2 = 293), we found that moral and pathogen disgust sensitivity differentially predicted perceptions of such COVID‐19 violations against mitigation actions, framed as a moral, pathogen, or on a good‐bad dimension, albeit in a less specific way than initially hypothesized (e.g., regarding the pathogenic framed violations, not only pathogen but also moral disgust was associated with higher perceptions of infectiousness). These results suggest that individual differences, especially in pathogen disgust (and, more inconsistently, moral disgust), are important when evaluating violations against mitigation actions. Further research on the role of moral disgust is needed.
Correlation of multiplicative functions over Fq[x]$\mathbb {F}_q[x]$: A pretentious approach
Authors: Darbar Pranendu , Mukhopadhyay Anirban
Published: October 2023

Let denote the set of monic polynomials of degree n over a finite field of q elements. For multiplicative functions , using the recently developed “pretentious method,” we establish a “local‐global” principle for correlation functions of the form
where are fixed polynomials. These results were then applied to find limiting distributions of sums of additive functions. We also study correlations with Dirichlet characters and Hayes characters. As a consequence, we give a new proof of a function field analog of Kátai's conjecture that states that if the average of the first divided difference of a completely multiplicative function whose values lie on the unit circle is zero, then it must be a Hayes character. We further extend this result to pairs and triplets of completely multiplicative functions.
Effects of temperature on calcium current of bullfrog sympathetic neurons.
Authors: van Lunteren E , Elmslie K S , Jones S W
Published: October 2023

1. The temperature dependence of whole‐cell calcium current was studied in bullfrog sympathetic neurons. 2. The factor by which the peak calcium current increased upon a 10 degrees C increase in temperature (Q10) was 1.6 +/‐ 0.1 (mean +/‐ S.E.M., n = 9), for a change from 20 to 30 degrees C. 3. Activation and deactivation were more rapid at a higher temperature. The Q10 was approximately 7 in the middle of the voltage range (near ‐10 mV), where the kinetics were slowest. Time constants were less temperature dependent at more positive or negative voltages (Q10 approximately 2 at ‐70 mV). 4. Near ‐10 mV, activation and deactivation were associated with a large enthalpy and a large positive entropy change. Deactivation at ‐70 mV reflected a smaller enthalpy change, and almost no change in entropy. 5. Activation is only slightly more temperature dependent than deactivation, when both are measured at the same voltage. 6. The peak current shifts slightly (approximately 5 mV) to more negative voltages upon a change from 20 to 30 degrees C. 7. Inactivation has a Q10 of approximately 2 at ‐10 mV. 8. Changes in the kinetics of activation or inactivation could be observed during recording at a constant temperature. These changes were generally small, especially for activation kinetics, and could be distinguished from temperature‐dependent changes. 9. The changes in entropy and Q10 with voltage suggest that the rate‐limiting steps for activation and deactivation are different at extreme voltages vs. the middle of the voltage range.
Co‐existence and elimination of convergent motor nerve terminals in reinnervated and paralysed adult rat skeletal muscle.
Authors: Ribchester R R
Published: October 2023

1. Experiments were carried out to determine whether neuromuscular synapse elimination can occur in skeletal muscle in the complete absence of conducted neural activity, using reinnervation of partially denervated adult muscle as a paradigm. Partially denervated rat lumbrical muscles were paralysed with a nerve conduction block applied to the sciatic nerve during regeneration of injured sural nerve motor axons. Both intact (lateral plantar nerve) and regenerating motor axons converging on the same muscle fibres were therefore inactive. 2. Paralysed muscles expressed prolonged twitch contractions, low tetanus‐to‐twitch ratios, prolonged synaptic potentials and marked post‐tetanic potentiation of frequency of miniature endplate potentials compared with control muscles and neuromuscular junctions. 3. Isometric tension and intracellular recording data suggest that regenerating axons reinnervated more muscle fibres in paralysed muscles than in controls. A greater proportion of muscle fibres was polyneuronally innervated in the paralysed muscles, but significant numbers of muscle fibres acquired a mononeuronal innervation by regenerated, inactive motor nerve terminals. 4. The data suggest that muscle paralysis enhances the regeneration of motor axons when they grow into partially denervated muscles, but activity‐independent competition may also be important in the mechanism of synapse elimination at neuromuscular junctions. The data further imply that when nerve endings expressing identical patterns of activity converge on a postsynaptic cell, Hebbian rules may not be sufficient to predict the outcome of the competition, contrary to specific postulates of the neurotrophic theory of development and maintenance of neural connections.
An Electro-Chemo-Mechanical Theory With Flexoelectricity: Application to Ionic Conductivity of Soft Solid Electrolytes
Authors: Mathew Anand , Kulkarni Yashashree
Published: October 2023

Flexible batteries are gaining momentum in several fields, including wearable medical devices and biomedical sensors, flexible displays, and smartwatches. These energy storage devices are subjected to electro-chemo-mechanical effects. Here, we present a theoretical framework that couples diffusion and electromechanical theory with flexoelectricity. As an example, we investigate the effect of flexoelectricity on the ionic conductivity in soft materials. Our analytical results for a thin film made of a soft material reveal that the ionic conductivity is significantly higher at the nanoscale and decreases exponentially to approach the bulk value with increasing film thickness. Furthermore, we find that flexoelectricity reduces the ionic conductivity dramatically at film thickness smaller than the length scale associated with flexoelectricity. This behavior is attributed to the opposite directions of polarization induced by flexoelectricity and the flow of ions driven by the chemical potential. These findings shed light on the interplay between flexoelectricity and diffusion which would be paramount in designing miniaturized energy storage devices.
Microscopic study of submonolayer nucleation characteristics during GaN (0001) homoepitaxial growth
Authors: Su Peng , Ai Wensen , Chen Xuejiang , Liu Lijun
Published: October 2023

An on-lattice kinetic Monte Carlo model is constructed to investigate microscopic nucleation behavior during the submonolayer epitaxial growth of GaN islands, where the Ga and N atoms are treated as the basic particles. The input kinetic parameters of Ga and N, including their surface diffusion energy barriers, were obtained from previous ab initio calculations. Furthermore, a simple and effective bond counting rule is applied in our kinetic Monte Carlo model, and the statistics of the GaN islands on the surface are realized via the application of the Hoshen–Kopelman algorithm. The growth temperature range covers the typical growth temperatures used in the molecular beam epitaxy of GaN. The results obtained show that triangular GaN flakes are observed and that the shapes of the GaN islands remain triangular when the growth temperature is changed. Additionally, the power law for the maximum density of islands versus the ratio of the effective diffusion to the deposition rate is obtained; the exponent of this law is −0.506 ± 0.006, indicating that these triplets represent the seeds required for further nucleation. Finally, the coexistence of the Ga-edge and N-edge types of triangular GaN islands is observed. The island formation mechanism is attributed to a local monomer density misbalance, and it is also shown that a slight variation in the Ga/N ratio in the deposition flux changes the proportion of the Ga-edge and N-edge type triangles; this represents a further indication that controllable GaN morphologies can be obtained by tuning the chemical potentials of the constituent elements.
Adaptation of the Recreovía During COVID-19 Lockdowns: Making Physical Activity Accessible to Older Adults in Bogotá, Colombia
Authors: González Silvia A. , Adlakha Deepti , Cabas Santiago , Sánchez-Franco Sharon C. , Rubio Maria A. , Ossa Natalia , Martínez Paola A. , Espinosa Nathally , Sarmiento Olga L.
Published: October 2023

The community restrictions during the coronavirus disease 2019 pandemic adversely impacted older adults’ physical activity levels. This convergent mixed-method study assessed the adaptation of the Recreovía, a community-based physical activity program in Bogotá, and characterized physical activity levels among older adult participants. Our results showed how the Recreovía adapted during the pandemic to continue promoting physical activity, through indoor and outdoor strategies, including virtual physical activity sessions and safety protocols. During this time, 72%–79% of the older adults attending the adapted program were physically active. A greater proportion of park users (84.2%) and more people involved in vigorous physical activity were observed during Recreovía days. Older adults had positive experiences and perceptions of the Recreovía program related to their health and social well-being. Even though the older adults prefer being outdoors, the adapted program allowed participants to continue with their physical activity routines as much as possible during the pandemic.
Synaptic BMAL1 phosphorylation controls circadian hippocampal plasticity
Authors: Barone Ilaria , Gilette Nicole M. , Hawks-Mayer Hannah , Handy Jonathan , Zhang Kevin J. , Chifamba Fortunate F. , Mostafa Engie , Johnson-Venkatesh Erin M. , Sun Yan , Gibson Jennifer M. , Rotenberg Alexander , Umemori Hisashi , Tsai Peter T. , Lipton Jonathan O.
Published: October 2023

The time of day strongly influences adaptive behaviors like long-term memory, but the correlating synaptic and molecular mechanisms remain unclear. The circadian clock comprises a canonical transcription-translation feedback loop (TTFL) strictly dependent on the BMAL1 transcription factor. We report that BMAL1 rhythmically localizes to hippocampal synapses in a manner dependent on its phosphorylation at Ser
42
[pBMAL1(S42)]. pBMAL1(S42) regulates the autophosphorylation of synaptic CaMKIIα and circadian rhythms of CaMKIIα-dependent molecular interactions and LTP but not global rest/activity behavior. Therefore, our results suggest a model in which repurposing of the clock protein BMAL1 to synapses locally gates the circadian timing of plasticity.
Universal scaling of the dynamic BKT transition in quenched 2D Bose gases
Authors: Sunami Shinichi , Singh Vijay Pal , Garrick David , Beregi Abel , Barker Adam J. , Luksch Kathrin , Bentine Elliot , Mathey Ludwig , Foot Christopher J.
Published: October 2023

The understanding of nonequilibrium dynamics in many-body quantum systems is a fundamental issue in statistical physics. Experiments that probe universal properties of these systems can address such foundational questions. In this study, we report the measurement of universal dynamics triggered by a quench from the superfluid to normal phase across the Berezinskii-Kosterlitz-Thouless transition in a two-dimensional (2D) Bose gas. We reduced the density by splitting the 2D gas in two, realizing a quench across the critical point. The subsequent relaxation dynamics were probed with matter-wave interferometry to measure the local phase fluctuations. We show that the time evolution of both the phase correlation function and vortex density obeys universal scaling laws. This conclusion is supported by classical-field simulations and interpreted by means of real-time renormalization group theory.
Artificial intelligence and interspecific law
Authors: Gervais Daniel J. , Nay John J.
Published: October 2023

Law could recognize nonhuman AI-led corporate entities
Interconverting mirror-image molecules
Authors: Kim Sojung F. , Sarpong Richmond
Published: October 2023

A light-driven multitasking catalyst enhances chirality in molecular mixtures
First malaria vaccine slashes childhood deaths
Authors: Wadman Meredith
Published: October 2023

Final evaluation brings good news from RTS,S rollout
DGKα/ζ inhibitors combine with PD-1 checkpoint therapy to promote T cell–mediated antitumor immunity
Authors: Wichroski Michael , Benci Joseph , Liu Si-Qi , Chupak Louis , Fang Jie , Cao Carolyn , Wang Cindy , Onorato Joelle , Qiu Hongchen , Shan Yongli , Banas Dana , Powles Ryan , Locke Gregory , Witt Abigail , Stromko Caitlyn , Qi Huilin , Zheng Xiaofan , Martin Scott , Ding Min , Gentles Robert , Meanwell Nicholas , Velaparthi Upender , Olson Richard , Wee Susan , Tenney Daniel , Parker Christopher G. , Cravatt Benjamin F. , Lawrence Michael , Borzilleri Robert , Lees Emma
Published: October 2023

Programmed cell death protein 1 (PD-1) immune checkpoint blockade therapy has revolutionized cancer treatment. Although PD-1 blockade is effective in a subset of patients with cancer, many fail to respond because of either primary or acquired resistance. Thus, next-generation strategies are needed to expand the depth and breadth of clinical responses. Toward this end, we designed a human primary T cell phenotypic high-throughput screening strategy to identify small molecules with distinct and complementary mechanisms of action to PD-1 checkpoint blockade. Through these efforts, we selected and optimized a chemical series that showed robust potentiation of T cell activation and combinatorial activity with αPD-1 blockade. Target identification was facilitated by chemical proteomic profiling with a lipid-based photoaffinity probe, which displayed enhanced binding to diacylglycerol kinase α (DGKα) in the presence of the active compound, a phenomenon that correlated with the translocation of DGKα to the plasma membrane. We further found that optimized leads within this chemical series were potent and selective inhibitors of both DGKα and DGKζ, lipid kinases that constitute an intracellular T cell checkpoint that blunts T cell signaling through diacylglycerol metabolism. We show that dual DGKα/ζ inhibition amplified suboptimal T cell receptor signaling mediated by low-affinity antigen presentation and low major histocompatibility complex class I expression on tumor cells, both hallmarks of resistance to PD-1 blockade. In addition, DGKα/ζ inhibitors combined with αPD-1 therapy to elicit robust tumor regression in syngeneic mouse tumor models. Together, these findings support targeting DGKα/ζ as a next-generation T cell immune checkpoint strategy.
A conceptual framework for nomenclatural stability and validity of medically important fungi: a proposed global consensus guideline for fungal name changes supported by ABP, ASM, CLSI, ECMM, ESCMID-EFISG, EUCAST-AFST, FDLC, IDSA, ISHAM, MMSA, and MSGERC
Authors: de Hoog Sybren , Walsh Thomas J. , Ahmed Sarah A. , Alastruey-Izquierdo Ana , Alexander Barbara D. , Arendrup Maiken Cavling , Babady Esther , Bai Feng-Yan , Balada-Llasat Joan-Miquel , Borman Andrew , Chowdhary Anuradha , Clark Andrew , Colgrove Robert C. , Cornely Oliver A. , Dingle Tanis C. , Dufresne Philippe J. , Fuller Jeff , Gangneux Jean-Pierre , Gibas Connie , Glasgow Heather , Gräser Yvonne , Guillot Jacques , Groll Andreas H. , Haase Gerhard , Hanson Kimberly , Harrington Amanda , Hawksworth David L. , Hayden Randall T. , Hoenigl Martin , Hubka Vit , Johnson Kristie , Kus Julianne V. , Li Ruoyu , Meis Jacques F. , Lackner Michaela , Lanternier Fanny , Leal Jr. Sixto M. , Lee Francesca , Lockhart Shawn R. , Luethy Paul , Martin Isabella , Kwon-Chung Kyung J. , Meyer Wieland , Nguyen M. Hong , Ostrosky-Zeichner Luis , Palavecino Elizabeth , Pancholi Preeti , Pappas Peter G. , Procop Gary W. , Redhead Scott A. , Rhoads Daniel D. , Riedel Stefan , Stevens Bryan , Sullivan Kaede Ota , Vergidis Paschalis , Roilides Emmanuel , Seyedmousavi Amir , Tao Lili , Vicente Vania A. , Vitale Roxana G. , Wang Qi-Ming , Wengenack Nancy L. , Westblade Lars , Wiederhold Nathan , White Lewis , Wojewoda Christina M. , Zhang Sean X.
Published: October 2023

The rapid pace of name changes of medically important fungi is creating challenges for clinical laboratories and clinicians involved in patient care. We describe two sources of name change which have different drivers, at the species versus the genus level. Some suggestions are made here to reduce the number of name changes. We urge taxonomists to provide diagnostic markers of taxonomic novelties. Given the instability of phylogenetic trees due to variable taxon sampling, we advocate to maintain genera at the largest possible size. Reporting of identified species in complexes or series should where possible comprise both the name of the overarching species and that of the molecular sibling, often cryptic species. Because the use of different names for the same species will be unavoidable for many years to come, an open access online database of the names of all medically important fungi, with proper nomenclatural designation and synonymy, is essential. We further recommend that while taxonomic discovery continues, the adaptation of new name changes by clinical laboratories and clinicians be reviewed routinely by a standing committee for validation and stability over time, with reference to an open access database, wherein reasons for changes are listed in a transparent way.
Alphavirus-based replicons demonstrate different interactions with host cells and can be optimized to increase protein expression
Authors: Dominguez Francisco , Palchevska Oksana , Frolova Elena I. , Frolov Ilya
Published: October 2023

Alphaviruses have been used as vectors for the expression of heterologous genetic information for a few decades. Their genomes contain two open reading frames. One of these encodes viral nonstructural proteins (nsPs), which mediate the replication of viral genome (G RNA) and synthesis of subgenomic (SG) RNA. Viral structural proteins encoded by SG RNA are dispensable for G RNA replication and transcription of the SG RNA. Their genes can be replaced by heterologous genetic materials. Such defective viral genomes, replicons, can efficiently express the encoded heterologous genes of interest. Within recent years, alphavirus replicons, also termed self-amplifying RNAs (saRNAs), attracted additional attention as a tool to increase the expression level of mRNA vaccines. The results of this study demonstrate that replicons derived from both New World and Old World alphaviruses can efficiently express heterologous genetic information. However, the levels of expression are cell-specific and are strongly determined by the origin of the replicons. Moreover, replication of alphavirus replicons mimics many aspects of alphavirus infections in terms of virus-host interactions and induction of the innate immune response. They also express viral nsPs that may induce vector immunity. These characteristics need to be carefully examined before the wide application of saRNAs. On the other hand, the data show that alphavirus replicons are very flexible expression systems. The efficiencies of protein expression and interactions with host cells can be manipulated by introducing mutations into nsPs and other modifications in replicon genomes.

IMPORTANCE

Alphavirus replicons are being developed as self-amplifying RNAs aimed at improving the efficacy of mRNA vaccines. These replicons are convenient for genetic manipulations and can express heterologous genetic information more efficiently and for a longer time than standard mRNAs. However, replicons mimic many aspects of viral replication in terms of induction of innate immune response, modification of cellular transcription and translation, and expression of nonstructural viral genes. Moreover, all replicons used in this study demonstrated expression of heterologous genes in cell- and replicon’s origin-specific modes. Thus, many aspects of the interactions between replicons and the host remain insufficiently investigated, and further studies are needed to understand the biology of the replicons and their applicability for designing a new generation of mRNA vaccines. On the other hand, our data show that replicons are very flexible expression systems, and additional modifications may have strong positive impacts on protein expression.
Duck Tembusu virus NS3 protein induces apoptosis by activating the PERK/PKR pathway and mitochondrial pathway
Authors: Pan Yuhong , Cai Wenjun , Cheng Anchun , Wang Mingshu , Huang Juan , Chen Shun , Yang Qiao , Wu Ying , Sun Di , Mao Sai , Zhu Dekang , Liu Mafeng , Zhao Xinxin , Zhang Shaqiu , Gao Qun , Ou Xumin , Tian Bin , Yin Zhongqiong , Jia Renyong
Published: October 2023

Duck Tembusu virus (DTMUV) infection causes severe infectious diseases in poultry and can induce apoptosis in host cells. In this study, the mechanisms underlying DTMUV-induced apoptosis were investigated. First, DTMUV infection can activate the endoplasmic reticulum stress (ERS), and administration of the ERS inhibitor 4-phenylbutyric acid can protect cells from DTMUV-induced apoptosis, indicating that ERS is involved in DTMUV-induced apoptosis. Interestingly, suppression of either apoptosis or ERS led to impaired DTMUV proliferation. Then, we found that DTMUV activated three branches of unfolded protein response signaling [RNA-activated protein kinase-like endoplasmic reticulum kinase (PERK), inositol-requiring enzyme 1, and activating transcription factor 6] in duck embryo fibroblasts. Further study revealed that activation of PERK-eukaryotic initiation factor 2α up-regulated CCAAT/enhancer-binding protein homologous protein and DNA damage-inducible protein 34, which subsequently promoted apoptosis. Moreover, we found that among the DTMUV viral proteins, the nonstructural protein 3 (NS3) is the main inducer of apoptosis. On the one hand, the PERK/PKR pathway is involved in the NS3-mediated mitochondrial apoptosis pathway. On the other hand, NS3 interacts with voltage-dependent anion channel 2 (VDAC2) and inhibits the anti-apoptotic protein VDAC2 to induce apoptosis, which is accompanied by the depolarization of mitochondrial membrane potential and accumulation of intracellular reactive oxygen species. This study provides a theoretical basis for revealing the pathogenic mechanism of DTMUV infection and lays a foundation for finding antiviral targets.

IMPORTANCE

Duck Tembusu virus (DTMUV) is an emerging pathogenic flavivirus that replicates well in mosquito, bird, and mammalian cells. An
in vivo
study revealed that BALB/c mice and Kunming mice were susceptible to DTMUV after intracerebral inoculation. Moreover, there are no reports about DTMUV-related human disease, but antibodies against DTMUV and viral RNA were detected in the serum samples of duck industry workers. This information implies that DTMUV has expanded its host range and poses a threat to mammalian health. Thus, understanding the pathogenic mechanism of DTMUV is crucial for identifying potential antiviral targets. In this study, we discovered that NS3 can induce the mitochondria-mediated apoptotic pathway through the PERK/PKR pathway; it can also interact with voltage-dependent anion channel 2 to induce apoptosis. Our findings provide a theoretical basis for understanding the pathogenic mechanism of DTMUV infection and identifying potential antiviral targets and may also serve as a reference for exploring the pathogenesis of other flaviviruses.
Adaptation to bile and anaerobicity limits
Vibrio cholerae
phage adsorption
Authors: Netter Zoe , Dunham Drew T. , Seed Kimberley D.
Published: October 2023

Bacteriophages (viruses of bacteria) play a pivotal role in shaping both the evolution and dynamics of bacterial populations. Bacteria employ arsenals of genetically encoded phage defense systems, but can alternatively achieve protection by changing the availability of cellular resources that phages rely on for propagation. These physiological changes are often adaptive responses to unique environmental signals. The facultative pathogen
Vibrio cholerae
adapts to both aquatic and intestinal environments with niche-specific physiological changes that ensure its evolutionary success in such disparate settings. In both niches,
V. cholerae
is susceptible to predation by lytic phages like ICP1. However, both phages and susceptible bacterial hosts coexist in nature, indicating that environmental cues may modulate
V. cholerae
cell state to protect against phage infection. This work explores one such modification in response to the intestine-specific signals of bile and anaerobicity. We found that
V. cholerae
grown in these conditions reduces O1-antigen decoration on its outer membrane lipopolysaccharide. Because the O1-antigen is an essential moiety for ICP1 phage infection, we investigated the effect of partial O1-antigen depletion as a mechanism of phage defense and observed that O1-depletion limits phage adsorption. We identified mechanistic contributions to O1-depletion, including the essentiality of a weak acid tolerance system for O1 production at low pH and alterations in transcriptional profiles indicating limitations in resources for O1-biosynthesis. This analysis illustrates a complex interplay between signals relevant to the intestinal environment and bacterial physiology that provides
V. cholerae
with protection from phage predation.

IMPORTANCE

Vibrio cholerae
is the bacterial pathogen responsible for cholera, a diarrheal disease that impacts people in areas without access to potable water. In regions that lack such infrastructure, cholera represents a large proportion of disease outbreaks. Bacteriophages (phages, viruses that infect bacteria) have recently been examined as potential therapeutic and prophylactic agents to treat and prevent bacterial disease outbreaks like cholera due to their specificity and stability. This work examines the interaction between
V. cholerae
and vibriophages in consideration for a cholera prophylaxis regimen (M. Yen, L. S. Cairns, and A. Camilli, Nat Commun 8:14187, 2017,
https://doi.org/10.1038/ncomms14187
) in the context of stimuli found in the intestinal environment. We discover that common signals in the intestinal environment induce cell surface modifications in
V. cholerae
that also restrict some phages from binding and initiating infection. These findings could impact considerations for the design of phage-based treatments, as phage infection appears to be limited by bacterial adaptations to the intestinal environment.
Genome-wide screens reveal shared and strain-specific genes that facilitate enteric colonization by
Klebsiella pneumoniae
Authors: Cheung Bettina H. , Alisoltani Arghavan , Kochan Travis J. , Lebrun-Corbin Marine , Nozick Sophia H. , Axline Christopher M. R. , Bachta Kelly E. R. , Ozer Egon A. , Hauser Alan R.
Published: October 2023

Gastrointestinal (GI) colonization by
Klebsiella pneumoniae
is a risk factor for subsequent infection as well as transmission to other patients. Additionally, colonization is achieved by many strain types that exhibit high diversity in genetic content. Thus, we aimed to study strain-specific requirements for
K. pneumoniae
GI colonization by applying transposon insertion sequencing to three classical clinical strains: a carbapenem-resistant strain, an extended-spectrum beta-lactamase-producing strain, and a non-epidemic antibiotic-susceptible strain. The transposon insertion libraries were screened in a murine model of GI colonization. At 3 days post-inoculation, 27 genes were required by all three strains for colonization. Isogenic deletion mutants for three genes/operons (
acrA
,
carAB
, and
tatABCD
) confirmed colonization defects in each of the three strains. Additionally, deletion of
acrA
reduced bile tolerance
in vitro
, while complementation restored both bile tolerance
in vitro
and colonization ability
in vivo
. Transposon insertion sequencing suggested that some genes were more important for the colonization of one strain than the others. For example, deletion of the sucrose porin-encoding gene
scrY
resulted in a colonization defect in the carbapenemase-producing strain but not in the extended-spectrum beta-lactamase producer or the antibiotic-susceptible strain. These findings demonstrate that classical
K. pneumoniae
strains use both shared and strain-specific strategies to colonize the mouse GI tract.

IMPORTANCE

Klebsiella pneumoniae
is a common cause of difficult-to-treat infections due to its propensity to express resistance to many antibiotics. For example, carbapenem-resistant
K. pneumoniae
has been named an urgent threat by the United States Centers for Disease Control and Prevention. Gastrointestinal colonization in patients with
K. pneumoniae
has been linked to subsequent infection, making it a key process to control in the prevention of multidrug-resistant infections. However, the bacterial factors which contribute to
K. pneumoniae
colonization are not well understood. Additionally, individual strains exhibit large amounts of genetic diversity, begging the question of whether some colonization factors are strain dependent. This study identifies the enteric colonization factors of three classical strains using transposon mutant screens to define a core colonization program for
K. pneumoniae
as well as detecting strain-to-strain differences in colonization strategies.
Contrasting roles of MERS-CoV and SARS-CoV-2 internal proteins in pathogenesis in mice
Authors: Wong Lok-Yin Roy , Odle Abby , Luhmann Emma , Wu Douglas C. , Wang Yiquan , Teo Qi Wen , Ptak Celeste , Sariol Alan , Lowery Shea , Mack Matthias , Meyerholz David K. , Wu Nicholas C. , Radoshevich Lilliana , Perlman Stanley
Published: October 2023

Betacoronaviruses encode an internal (I) gene via an alternative reading frame within the nucleocapsid gene, called ORF8b for
M
iddle-
E
ast
r
espiratory
s
yndrome
c
oronavirus (MERS-CoV) and ORF9b for
s
evere
a
cute
r
espiratory
s
yndrome
c
oronavirus (SARS-CoV) and SARS-CoV-2. Previous reports suggested that proteins 8b and 9b are involved in evading multiple innate immune signaling pathways. However, their roles in mediating pathogenesis in infected animals have not been determined. In this study, we abrogated the expression of protein 8b in MERS-CoV and protein 9b in SARS-CoV-2. Using mouse models of MERS-CoV and SARS-CoV-2 infection, we found that MERS-CoV lacking protein 8b expression was more virulent, while SARS-CoV-2 lacking protein 9b expression was attenuated compared with the respective wild-type viruses. Upon further analysis, we detected increased levels of type I interferon and enhanced infiltration of immune cells to the lungs of mice infected with MERS-CoV lacking protein 8b expression. These data suggest that the I protein of MERS-CoV plays a role in limiting pathogenesis while that of SARS-CoV-2 enhances disease severity.

IMPORTANCE

The function of betacoronavirus internal protein has been relatively understudied. The earliest report on the internal protein of mouse hepatitis virus suggested that the internal protein is a structural protein without significant functions in virus replication and virulence. However, the internal proteins of
s
evere
a
cute
r
espiratory
s
yndrome
c
oronavirus (SARS-CoV), Middle-East respiratory syndrome coronavirus, and SARS-CoV-2 have been shown to evade immune responses. Despite the reported functions of the internal protein in these highly pathogenic human coronaviruses, its role in mediating pathogenesis in experimentally infected animals has not been characterized. Our data indicated that despite the similar genomic location and expression strategy of these internal proteins, their effects on virulence are vastly different and virus specific, highlighting the complexity between host-virus interaction and disease outcome.
Current management of neonatal abstinence syndrome: a survey of practice in the UK and Ireland
Authors: Dempsey Sharon , O’ Grady Michael J
Published: October 2023

Objective

To study the current management practices of neonatal abstinence syndrome (NAS) throughout the UK and Ireland and identify changes in practice from the most recent survey in 2008.

Design

Postal questionnaire to a consultant paediatrician or neonatologist in all 215 neonatal units in the UK and Ireland in January 2020.

Results

Response rate was 62%. An objective scoring tool was used in 97% of units and the Finnegan score was favoured by 70%. Morphine sulfate use as first line for the treatment of opiate withdrawal was almost universal and 70% used a dose of 40 µg/kg every 4 hours (240 µg/kg/day). Phenobarbitone administration as a second-line agent for opiate withdrawal increased to 61% of units with significant reductions in chloral hydrate and chlorpromazine use compared with the previous survey. Morphine sulfate and phenobarbitone remain the preferred first-line and second-line agents, respectively, for polysubstance withdrawal. There was a significant increase in chlorpromazine use as first line for polydrug withdrawal (1.5–14.2%). The practice of units discharging infants’ home on medication increased to 46% from 29%. All units now permit breastfeeding in mothers taking methadone, compared with 81% previously.

Conclusion and relevance

Compared with the previous survey, improvements in evidence-based practices were noted, highlighting the benefits of this type of research. Nonetheless, significant variation still exists in some aspects of the management of NAS. Post-discharge follow-up varies widely, with particular deficits in ophthalmology follow-up.
Pericanalicular eccrine hidrocystoma of the upper eyelid in a child
Authors: Natarajan Kaviyapriya , Pratima Gajanan Chavhan , Kasturi Nirupama , Nachiappa Ganesh Rajesh
Published: October 2023

A rare case of pericanalicular eccrine hidrocystoma of the upper eyelid is reported in a child who underwent surgical excision and canalicular repair with a successful outcome.
Drug-induced liver injury with autoimmune features secondary to infliximab for ulcerative colitis
Authors: Gemmell Ailsa , Fraser Andrew , Oien Karin , Seenan John Paul
Published: October 2023

We present a patient with a drug-induced liver injury with autoimmune features as a result of infliximab therapy for ulcerative colitis. This is a rare but serious side effect in patients receiving this treatment which clinicians should consider in the event of liver function test derangement.
Three-year remission of metastatic breast cancer with treatment with ado-trastuzumab emtansine
Authors: Caramujo Cecília , Reis Sara Nunes , Garcia Ana Rita , Sousa Gabriela
Published: October 2023

Globally, breast cancer is the most frequently diagnosed malignancy and the leading cause of oncological death in women. Metastatic disease at diagnosis (de novo stage IV breast cancer) will be identified in about 5% of patients. Treatment options vary based on several factors, namely whether the tumour is hormone receptor positive and whether human epidermal growth factor receptor 2 (HER2) is overexpressed. Here, we report a case of HER2 positive metastatic breast cancer on a woman in her late 30s, with remission for over 3 years under second-line treatment with ado-trastuzumab emtansine, with no significant toxicity and good tolerability. The timing to stop treatment under these circumstances presents a challenge and more data are needed to substantiate the decision to stop or maintain treatment in this small population.
Unexpected cause of Kounis syndrome: hypersensitivity reaction to omeprazole
Authors: Erdem Almina , Çınar Tufan , Kılıç Şahhan , Öztürk Nazlı Begüm
Published: October 2023

Kounis syndrome is a rare type of acute coronary syndrome (ACS) that occurs as a result of an allergic or anaphylactic reaction. Kounis syndrome can be induced by various medications including antibiotics, proton pump inhibitors, antihypertensive medications, corticosteroids, and antineoplastic medications. Additionally, cases of Kounis syndrome associated with lansoprazole and pantoprazole have been previously reported in the literature. In this report, we present a case of Kounis syndrome associated with omeprazole use, and discuss the need for a high index of suspicion as it is often underrecognised.
Abstracts from international emergency medicine journals
Authors: Production EMJ
Published: October 2023

Editor’s note: EMJ has partnered with the journals of multiple international emergency medicine societies to share from each a highlighted research study, as selected by their editors. This edition will feature an abstract from each publication.