Nanoscale Three-Dimensional Imaging of Integrated Circuits Using a Scanning Electron Microscope and Transition-Edge Sensor Spectrometer.

X-ray nanotomography is a powerful tool for the characterization of nanoscale materials and structures, but it is difficult to implement due to the competing requirements of X-ray flux and spot size. Due to this constraint, state-of-the-art nanotomography is predominantly performed at large synchrotron facilities. We present a laboratory-scale nanotomography instrument that achieves nanoscale spatial resolution while addressing the limitations of conventional tomography tools. The instrument combines the electron beam of a scanning electron microscope (SEM) with the precise, broadband X-ray detection of a superconducting transition-edge sensor (TES) microcalorimeter. The electron beam generates a highly focused X-ray spot on a metal target held micrometers away from the sample of interest, while the TES spectrometer isolates target photons with a high signal-to-noise ratio. This combination of a focused X-ray spot, energy-resolved X-ray detection, and unique system geometry enables nanoscale, element-specific X-ray imaging in a compact footprint. The proof of concept for this approach to X-ray nanotomography is demonstrated by imaging 160 nm features in three dimensions in six layers of a Cu-SiO2 integrated circuit, and a path toward finer resolution and enhanced imaging capabilities is discussed.

Highlights from the 2023 International Meeting on the Molecular Biology of Hepatitis B virus.

Since its discovery in 1965, our understanding of the hepatitis B virus (HBV) replication cycle and host immune responses has increased markedly. In contrast, our knowledge of the molecular biology of hepatitis delta virus (HDV), which is associated with more severe liver disease, is less well understood. Despite the progress made, critical gaps remain in our knowledge of HBV and HDV replication and the mechanisms underlying viral persistence and evasion of host immunity. The International HBV Meeting is the leading annual scientific meeting for presenting the latest advances in HBV and HDV molecular virology, immunology, and epidemiology. In 2023, the annual scientific meeting was held in Kobe, Japan and this review summarises some of the advances presented at the Meeting and lists gaps in our knowledge that may facilitate the development of new therapies.

Signs or symptoms of suspected preeclampsia - A retrospective national database study of prevalence, costs, and outcomes.

BACKGROUND: Most patients with signs or symptoms (s/s) of suspected preeclampsia are not diagnosed with preeclampsia. We sought to determine and compare the prevalence of s/s, pregnancy outcomes, and costs between patients with and without diagnosed preeclampsia. METHODS: This retrospective cohort study analyzed a large insurance research database. Pregnancies with s/s of preeclampsia versus a confirmed preeclampsia diagnosis were identified using International Classification of Diseases codes. S/s include hypertension, proteinuria, headache, visual symptoms, edema, abdominal pain, and nausea/vomiting. Pregnancies were classed as 1) s/s of preeclampsia without a confirmed preeclampsia diagnosis (suspicion only), 2) s/s with a confirmed diagnosis (preeclampsia with suspicion), 3) diagnosed preeclampsia without s/s recorded (preeclampsia only), and 4) no s/s, nor preeclampsia diagnosis (control). RESULTS: Of 1,324,424 pregnancies, 29.2 % had ≥1 documented s/s of suspected preeclampsia, and 14.2 % received a preeclampsia diagnosis. Hypertension and headache were the most common s/s, leading 20.2 % and 9.2 % pregnancies developed to preeclampsia diagnosis, respectively. Preeclampsia, with or without suspicion, had the highest rates of hypertension-related severe maternal morbidity (HR [95 % CI]: 3.0 [2.7, 3.2] and 3.6 [3.3, 4.0], respectively) versus controls. A similar trend was seen in neonatal outcomes such as preterm delivery and low birth weight. Cases in which preeclampsia was suspected but not confirmed had the highest average total maternal care costs ($6096 [95 % CI: 602, 6170] over control). CONCLUSION: There is a high prevalence but poor selectivity of traditional s/s of preeclampsia, highlighting a clinical need for improved screening method and cost-effectiveness disease management.

Dynamic Copper Site Redispersion through Atom Trapping in Zeolite Defects.

Single-site copper-based catalysts have shown remarkable activity and selectivity for a variety of reactions. However, deactivation by sintering in high-temperature reducing environments remains a challenge and often limits their use due to irreversible structural changes to the catalyst. Here, we report zeolite-based copper catalysts in which copper oxide agglomerates formed after reaction can be repeatedly redispersed back to single sites using an oxidative treatment in air at 550 °C. Under different environments, single-site copper in Cu-Zn-Y/deAlBeta undergoes dynamic changes in structure and oxidation state that can be tuned to promote the formation of key active sites while minimizing deactivation through Cu sintering. For example, single-site Cu2+ reduces to Cu1+ after catalyst pretreatment (270 °C, 101 kPa H2) and further to Cu0 nanoparticles under reaction conditions (270-350 °C, 7 kPa EtOH, 94 kPa H2) or accelerated aging (400-450 °C, 101 kPa H2). After regeneration at 550 °C in air, agglomerated CuO was dispersed back to single sites in the presence and absence of Zn and Y, which was verified by imaging, in situ spectroscopy, and catalytic rate measurements. Ab initio molecular dynamics simulations show that solvation of CuO monomers by water facilitates their transport through the zeolite pore, and condensation of the CuO monomer with a fully protonated silanol nest entraps copper and reforms the single-site structure. The capability of silanol nests to trap and stabilize copper single sites under oxidizing conditions could extend the use of single-site copper catalysts to a wider variety of reactions and allows for a simple regeneration strategy for copper single-site catalysts.

Damage Control Laparotomy and Management of the Open Abdomen.

Management of the open abdomen has been used for decades by general surgeons. Techniques have evolved over those decades to improve control of infection, fluid loss, and improve the ability to close the abdomen to avoid hernia formation. The authors explore the history, indications, and techniques of open abdomen management in multiple settings. The most important considerations in open abdomen management include the reason for leaving the abdomen open, prevention and mitigation of ongoing organ dysfunction, and eventual plans for abdominal closure.

Oxygen-dependent histone lysine demethylase 4 restricts hepatitis B virus replication.

Mammalian cells have evolved strategies to regulate gene expression when oxygen is limited. Hypoxia-inducible factors (HIF) are the major transcriptional regulators of host gene expression. We previously reported that HIFs bind and activate hepatitis B virus (HBV) DNA transcription under low oxygen conditions; however, the global cellular response to low oxygen is mediated by a family of oxygenases that work in concert with HIFs. Recent studies have identified a role for chromatin modifiers in sensing cellular oxygen and orchestrating transcriptional responses, but their role in the HBV life cycle is as yet undefined. We demonstrated that histone lysine demethylase 4 (KDM4) can restrict HBV, and pharmacological or oxygen-mediated inhibition of the demethylase increases viral RNAs derived from both episomal and integrated copies of the viral genome. Sequencing studies demonstrated that KDM4 is a major regulator of the hepatic transcriptome, which defines hepatocellular permissivity to HBV infection. We propose a model where HBV exploits cellular oxygen sensors to replicate and persist in the liver. Understanding oxygen-dependent pathways that regulate HBV infection will facilitate the development of physiologically relevant cell-based models that support efficient HBV replication.

CTCF regulates hepatitis B virus cccDNA chromatin topology.

Hepatitis B Virus (HBV) is a small DNA virus that replicates via an episomal covalently closed circular DNA (cccDNA) that serves as the transcriptional template for viral mRNAs. The host protein, CCCTC-binding factor (CTCF), is a key regulator of cellular transcription by maintaining epigenetic boundaries, nucleosome phasing, stabilisation of long-range chromatin loops and directing alternative exon splicing. We previously reported that CTCF binds two conserved motifs within Enhancer I of the HBV genome and represses viral transcription, however, the underlying mechanisms were not identified. We show that CTCF depletion in cells harbouring cccDNA-like HBV molecules and in de novo infected cells resulted in an increase in spliced transcripts, which was most notable in the abundant SP1 spliced transcript. In contrast, depletion of CTCF in cell lines with integrated HBV DNA had no effect on the abundance of viral transcripts and in line with this observation there was limited evidence for CTCF binding to viral integrants, suggesting that CTCF-regulation of HBV transcription is specific to episomal cccDNA. Analysis of HBV chromatin topology by Assay for Transposase Accessible Chromatin Sequencing (ATAC-Seq) revealed an accessible region spanning Enhancers I and II and the basal core promoter (BCP). Mutating the CTCF binding sites within Enhancer I resulted in a dramatic rearrangement of chromatin accessibility where the open chromatin region was no longer detected, indicating loss of the phased nucleosome up- and down-stream of the HBV enhancer/BCP. These data demonstrate that CTCF functions to regulate HBV chromatin conformation and nucleosomal positioning in episomal maintained cccDNA, which has important consequences for HBV transcription regulation.

The N6-methyladenosine demethylase ALKBH5 regulates the hypoxic HBV transcriptome.

Chronic hepatitis B is a global health problem and current treatments only suppress hepatitis B virus (HBV) infection, highlighting the need for new curative treatments. Oxygen levels influence HBV replication and we previously reported that hypoxia inducible factors (HIFs) activate the basal core promoter (BCP). Here we show that the hypoxic-dependent increase in BCP-derived transcripts is dependent on N6-methyladenosine (m6A) modifications in the 5' stem loop that regulate RNA half-life. Application of a probe-enriched long-read sequencing method to accurately map the HBV transcriptome showed an increased abundance of pre-genomic RNA under hypoxic conditions. Mapping the transcription start sites of BCP-RNAs identified a role for hypoxia to regulate pre-genomic RNA splicing that is dependent on m6A modification. Bioinformatic analysis of published single cell RNA-seq of murine liver showed an increased expression of the RNA demethylase ALKBH5 in the peri-central low oxygen region. In vitro studies with a human hepatocyte derived HepG2-NTCP cell line showed increased ALKBH5 gene expression under hypoxic conditions and a concomitant reduction in m6A-modified HBV BCP-RNA and host RNAs. Silencing the demethylase reduced the level of BCP-RNAs and host gene (CA9, NDRG1, VEGFA, BNIP3, FUT11, GAP and P4HA1) transcripts and this was mediated via reduced HIFα expression. In summary, our study highlights a previously unrecognized role for ALKBH5 in orchestrating viral and cellular transcriptional responses to low oxygen.

Hypoxia inducible factors inhibit respiratory syncytial virus infection by modulation of nucleolin expression.

Respiratory syncytial virus (RSV) is a global healthcare problem, causing respiratory illness in young children and elderly individuals. Our knowledge of the host pathways that define susceptibility to infection and disease severity are limited. Hypoxia inducible factors (HIFs) define metabolic responses to low oxygen and regulate inflammatory responses in the lower respiratory tract. We demonstrate a role for HIFs to suppress RSV entry and RNA replication. We show that hypoxia and HIF prolyl-hydroxylase inhibitors reduce the expression of the RSV entry receptor nucleolin and inhibit viral cell-cell fusion. We identify a HIF regulated microRNA, miR-494, that regulates nucleolin expression. In RSV-infected mice, treatment with the clinically approved HIF prolyl-hydroxylase inhibitor, Daprodustat, reduced the level of infectious virus and infiltrating monocytes and neutrophils in the lung. This study highlights a role for HIF-signalling to limit multiple aspects of RSV infection and associated inflammation and informs future therapeutic approaches for this respiratory pathogen.

Q fever infection is a preventable risk associated with pet food manufacturing.

OBJECTIVE: This paper highlights the occupational risk of Q fever from exposure to raw animal products in the context of multiple notified Q fever cases from 2020 to 2023 linked to four pet food manufacturing facilities in South-East Queensland, Australia. METHODS: The Queensland Government Notifiable Conditions System was used to identify Q fever cases linked to pet food manufacturing in the Metro North and Gold Coast Hospital and Health Service areas of Brisbane, Australia. Data on each case from routine public health follow-up were collected and descriptively analysed. RESULTS: Between 2020 and 2023, 12 confirmed Q fever infections (17% of total cases) were linked to four pet food manufacturing facilities. Eleven cases reported direct or environmental exposure to raw meat and animal products. None were previously vaccinated for Q fever. CONCLUSION: These cases demonstrate the increased risk of Q fever infection as part of the pet food manufacturing process, highlighting an underappreciated preventable occupational risk, which can be mitigated with the use of pre-screening and vaccination of workers. All occupations should conduct workplace-based risk assessments to identify risks such as Q fever to prevent adverse negative health outcomes.

Consent practices in midwifery: A survey of UK midwives.

OBJECTIVE: To explore midwives' knowledge and understanding of the law and practice of consent in the post-Montgomery world. DESIGN: Cross-sectional online survey. Descriptive statistical analysis of midwives' survey responses. SETTINGS: Social media: Instagram, Facebook and Twitter. Survey distribution was via the UCL Opinio survey platform. PARTICIPANTS: A total of 402 midwives, surveyed over a four month period between 2nd March and 2nd July 2021. MEASUREMENTS: Knowledge of legal consent, 'sureness' of meeting current legal requirements and competence to gain consent. FINDINGS: 91% of participants acknowledged correctly that consent must be voluntary. 91% reported that women must be informed of all the risks associated with their care, although 26% reported that women should be informed of some of the risks associated with their care. Most participants were 'sure' that their discussions of consent meet current legal requirements (91%). 21% rated their competence to gain consent as 'excellent', 71% rated themselves as 'very good', whilst 1% rated their competence as 'poor'. Deficiencies in fundamental knowledge of consent were noted in some participants rating themselves highest in 'sureness' of meeting legal requirements and competence to consent. KEY CONCLUSIONS: Fundamental gaps in midwives' knowledge of legal consent were identified. Participants demonstrated uncertainty regarding the extent of risk disclosure and discussion of alternative care options. Participants generally rated themselves highly in their consenting practices, despite lacking in basic knowledge of legal consent, revealing a discrepancy between midwives' self-perceptions and their actual knowledge. IMPLICATIONS FOR PRACTICE: The overconfidence displayed by some participants is concerning for clinical midwifery practice. Professional education and guidance for midwives on legal consent in keeping with Montgomery is urgently required to ensure that midwives are legally compliant in their consenting practices.

The N6-methyladenosine demethylase ALKBH5 regulates the hypoxic HBV transcriptome.

Chronic hepatitis B is a global health problem and current treatments only suppress hepatitis B virus (HBV) infection, highlighting the need for new curative treatments. Oxygen levels influence HBV replication and we previously reported that hypoxia inducible factors (HIFs) activate the basal core promoter to transcribe pre-genomic RNA. Application of a probe-enriched long-read sequencing method to map the HBV transcriptome showed an increased abundance of all viral RNAs under low oxygen or hypoxic conditions. Importantly, the hypoxic-associated increase in HBV transcripts was dependent on N6-methyladenosine (m6A) modifications and an m6A DRACH motif in the 5' stem loop of pre-genomic RNA defined transcript half-life under hypoxic conditions. Given the essential role of m6A modifications in the viral transcriptome we assessed the oxygen-dependent expression of RNA demethylases and bioinformatic analysis of published single cell RNA-seq of murine liver showed an increased expression of the RNA demethylase ALKBH5 in the peri-central low oxygen region. In vitro studies with a human hepatocyte derived HepG2 cell line showed increased ALKBH5 gene expression under hypoxic conditions. Silencing the demethylase reduced the levels of HBV pre-genomic RNA and host gene (CA9, NDRG1, VEGFA, BNIP3, FUT11, GAP and P4HA1) transcripts and this was mediated via reduced HIFα expression. In summary, our study highlights a previously unrecognized role for ALKBH5 in orchestrating viral and cellular transcriptional responses to low oxygen.

Inappropriate dosing of direct oral anticoagulants: findings from a clinical vignette study and physician survey.

Objective: Direct oral anticoagulants (DOACs) are first-line therapy for stroke prevention for 1.4 million atrial fibrillation (AF) patients in the UK. However, the rates of DOAC dosing below evidence-based recommendations are estimated between 9% and 22%. This study explores specific patient and physician factors associated with prescribing inappropriate DOAC underdoses. Methods: DOAC-prescribing physicians within the UK completed both a clinical vignette survey, which contained 12 hypothetical patient profiles designed to replicate DOAC prescribing scenarios, and a physician survey to capture sociodemographic, clinical experience, and prescriber-related beliefs and motivations related to DOAC prescribing. Eight patient factors based on a literature search and an expert consultation process were varied within the vignettes. Associations between the prescribers' dosing choices and patient factors were explored via multilevel logistic regression. The analysis is focused on the most frequently selected DOACs, apixaban and rivaroxaban, both of which have different dosing guidelines. Results: In all, 336 prescribers (69% male; 233/336) completed the survey, mostly general physicians (GPs) (45%) or cardiology specialists (36%) with a mean of 17.9 years' experience. Most prescribers (73%; 244/336) inappropriately underdosed at least once; rates between GPs and specialists were nearly identical. Patient factors most strongly associated with apixaban inappropriate underdosing included a history of major bleeding and falls. For rivaroxaban, these were major bleeding and severe frailty. Only 32% (106/335) of prescribers reported DOAC dosing guidelines as the sole influence on their prescribing behaviour. Among prescribers who did not inappropriately underdose, greater prescribing confidence was aligned to increased perception of inappropriate underdose risk. Conclusions: Overall, patient factors such as major bleeding and severe frailty were found to be associated with inappropriate underdosing of apixaban and rivaroxaban. Furthermore, prescribers who were more confident in DOAC prescribing, and were more worried about the risk of stroke, were significantly less likely to inappropriately underdose. These findings suggest that all prescribers, regardless of speciality, may benefit from education and training to raise awareness of the risks associated with inappropriate DOAC underdosing.

Evaluating the benefit of serology during potential Australian bat lyssavirus and rabies post-exposure prophylaxis.

Post-exposure prophylaxis (PEP) for potential lyssavirus exposures consists of wound management, rabies vaccination and may include rabies immunoglobulin (RIG). Rabies serology is sometimes indicated if there is risk of PEP failure. OBJECTIVES: Evaluate the benefit of serology by indication. METHODS: Chart review of potential lyssavirus exposures managed at a Public Health Unit (June 2015 - December 2022) where serology was requested was conducted. The proportion of non-therapeutic titres was compared by sex, age, Indigenous status, serology indication, and whether RIG was given. RESULTS: 46 notifications with serology were included. Males (5/19) and people over 40 (3/16) were more likely to demonstrate a non-therapeutic response. 2/3 of cases where vaccine doses were not given in the deltoid were non-therapeutic. The rate of non-therapeutic titres was similar for RIG given into the ipsilateral arm (2/11) and given excess RIG for weight (1/4). Although this small sample was inconclusive in isolation, it was also noted that all cases who did not receive RIG had therapeutic serology, whereas 6/35 of those receiving RIG had non-therapeutic serology. CONCLUSIONS: This study supports broader literature questioning the utility of systemic RIG administration as likely limited and potentially detrimental considering the increased risk of immune interference. IMPLICATIONS FOR PUBLIC HEALTH: Highlights a need to review Australian national guidelines to align with World Health Organization advice recommending local RIG administration only.

Primary splenic multicystic peritoneal mesothelioma in a young healthy male.

Multicystic peritoneal mesothelioma (BMPM) is a rare, usually benign tumor that arises from peritoneal mesothelial cells that most commonly occurs in women of reproductive age. Pathogenesis of these tumors is thought to come from chronic inflammation from prior surgery, endometriosis, trauma, or recurrent peritonitis. Here we report a case of primary splenic BMPM in a 20-year-old male with no past medical or surgical history and without any typical risk factors for this condition. He underwent an open splenectomy without complication. Pathology revealed an 18 × 4 × 11 cm3 spleen with a cyst occupying 75% of the splenic surface. Sections revealed a multilocular cyst with trabeculated walls and immunohistochemical staining positive for cytokeratin (AE1/AE3) consistent with BMPM. One year post operatively he remains asymptomatic; however, his interval computed tomography (CT) scan revealed several sub centimeter nodules that either represents small splenules or neoplastic implants. These will be followed with close interval imaging.

Zeolite encapsulated organometallic complexes as model catalysts.

Heterogeneities in the structure of active centers in metal-containing porous materials are unavoidable and complicate the description of chemical events occurring along reaction coordinates at the atomic level. Metal containing zeolites include sites of varied local coordination and secondary confining environments, requiring careful titration protocols to quantify the predominant active sites. Hybrid organometallic-zeolite catalysts are useful well-defined platform materials for spectroscopic, kinetic, and computational studies of heterogeneous catalysis that avoid the complications of conventional metal-containing porous materials. Such materials have been synthesized and studied previously, but catalytic applications were mostly limited to liquid-phase oxidation and electrochemical reactions. The hydrothermal stability, time-on-stream stability, and utility of these materials in gas-phase oxidation reactions are under-studied. The potential applications for single-site heterogeneous catalysts in fundamental research are abundant and motivate future synthetic, spectroscopic, kinetic, and computational studies.

Evaluation and management of enuresis in the general paediatric setting.

Assessing enuresis involves distinguishing monosymptomatic from non-monosymptomatic for this common paediatric problem, and identifying concomitant comorbidities. Addressing co-occurring factors concurrently ensures the best opportunity for a satisfactory outcome. Treatment begins with patient and family education on the natural history of enuresis and practical behavioural guidance. Evidence to support particular interventions is limited, and children and families should be involved when choosing appropriate therapy. Enuresis alarms and desmopressin are treatment options when more active intervention is desired. Clinical refinements and combined treatment modalities are emerging.