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Background Accurate and efficient malaria diagnosis is critical for effective malaria control and elimination. Rapid diagnostic tests (RDTs) have been deployed over the last decade, particularly in rural and low-and-middle-income countries, as an alternative to microscopy-based diagnosis. Methods This study analysed retrospective health data from the Solomon Islands District Health Information System (DHIS2) for 2017–2019, focusing on factors affecting diagnostic test selection and positivity rates for microscopy versus RDTs. Results The national Annual Parasite Incidence (API) of malaria declined over the 3 years, with localised increases in specific health zones. The choice of malaria diagnostic test was associated with administrative division, patient age, health facility type and year. Overall, RDTs had higher malaria positivity rates than microscopy for both Plasmodium falciparum (microscopy, 6%; RDT, 11%) and Plasmodium vivax (microscopy, 10%; RDT, 14%). Conclusions RDTs were more widely used than microscopy in health facilities and had higher test positivity rates. This study highlights the factors influencing diagnostic test selection and underscores the importance of considering detection limits and potential overdiagnosis when interpreting positivity rates from different diagnostic methods.

INPP4B suppresses PI3K/AKT signaling by converting PI(3,4)P 2 to PI(3)P and INPP4B inactivation is common in triple-negative breast cancer. Paradoxically, INPP4B is also a reported oncogene in other cancers. How these opposing INPP4B roles relate to PI3K regulation is unclear. We report PIK3CA -mutant ER + breast cancers exhibit increased INPP4B mRNA and protein expression and INPP4B increased the proliferation and tumor growth of PIK3CA -mutant ER + breast cancer cells, despite suppression of AKT signaling. We used integrated proteomics, transcriptomics and imaging to demonstrate INPP4B localized to late endosomes via interaction with Rab7, which increased endosomal PI3Kα-dependent PI(3,4)P 2 to PI(3)P conversion, late endosome/lysosome number and cargo trafficking, resulting in enhanced GSK3β lysosomal degradation and activation of Wnt/β-catenin signaling. Mechanistically, Wnt inhibition or depletion of the PI(3)P-effector, Hrs, reduced INPP4B-mediated cell proliferation and tumor growth. Therefore, INPP4B facilitates PI3Kα crosstalk with Wnt signaling in ER + breast cancer via PI(3,4)P 2 to PI(3)P conversion on late endosomes, suggesting these tumors may be targeted with combined PI3K and Wnt/β-catenin therapies. The PI(3,4)P 2 4-phosphatase, INPP4B, functions as a tumour suppressor in triple negative breast cancer. Here, the authors show that INPP4B enhances proliferation and growth of PIK3CA -mutant ER +  breast cancers by promoting PI3Kα-dependent late endosome formation and trafficking that leads to the activation of Wnt/β-catenin signalling.

Effective control of infectious diseases is facilitated by informed decisions that require accurate and timely diagnosis of disease. For malaria, improved access to malaria diagnostics has revolutionized malaria control and elimination programmes. However, for COVID-19, diagnosis currently remains largely centralized and puts many low- and middle-income countries (LMICs) at a disadvantage. Malaria and COVID-19 are infectious diseases that share overlapping symptoms. While the strategic responses to disease control for malaria and COVID-19 are dependent on the disease ecologies of each disease, the fundamental need for accurate and timely testing remains paramount to inform accurate responses. This review highlights how the roll-out of rapid diagnostic tests has been fundamental in the fight against malaria, primarily within the Asia Pacific and along the Greater Mekong Subregion. By learning from the successful elements of malaria control programmes, it is clear that improving access to point-of-care testing strategies for COVID-19 will provide a suitable framework for COVID-19 diagnosis in not only the Asia Pacific, but all malarious countries. In malaria-endemic countries, an integrated approach to point-of-care testing for COVID-19 and malaria would provide bi-directional benefits for COVID-19 and malaria control, particularly due to their paralleled likeness of symptoms, infection control strategies and at-risk individuals. This is especially important, as previous disease pandemics have disrupted malaria control infrastructure, resulting in malaria re-emergence and halting elimination progress. Understanding and combining strategies may help to both limit disruptions to malaria control and support COVID-19 control.

Background Particular breast cancer subtypes pose a clinical challenge due to limited targeted therapeutic options and/or poor responses to the existing targeted therapies. While cell lines provide useful pre-clinical models, patient-derived xenografts (PDX) and organoids (PDO) provide significant advantages, including maintenance of genetic and phenotypic heterogeneity, 3D architecture and for PDX, tumor–stroma interactions. In this study, we applied an integrated multi-omic approach across panels of breast cancer PDXs and PDOs in order to identify candidate therapeutic targets, with a major focus on specific FGFRs. Methods MS-based phosphoproteomics, RNAseq, WES and Western blotting were used to characterize aberrantly activated protein kinases and effects of specific FGFR inhibitors. PDX and PDO were treated with the selective tyrosine kinase inhibitors AZD4547 (FGFR1-3) and BLU9931 (FGFR4). FGFR4 expression in cancer tissue samples and PDOs was assessed by immunohistochemistry. METABRIC and TCGA datasets were interrogated to identify specific FGFR alterations and their association with breast cancer subtype and patient survival. Results Phosphoproteomic profiling across 18 triple-negative breast cancers (TNBC) and 1 luminal B PDX revealed considerable heterogeneity in kinase activation, but 1/3 of PDX exhibited enhanced phosphorylation of FGFR1, FGFR2 or FGFR4. One TNBC PDX with high FGFR2 activation was exquisitely sensitive to AZD4547. Integrated ‘omic analysis revealed a novel FGFR2-SKI fusion that comprised the majority of FGFR2 joined to the C-terminal region of SKI containing the coiled-coil domains. High FGFR4 phosphorylation characterized a luminal B PDX model and treatment with BLU9931 significantly decreased tumor growth. Phosphoproteomic and transcriptomic analyses confirmed on-target action of the two anti-FGFR drugs and also revealed novel effects on the spliceosome, metabolism and extracellular matrix (AZD4547) and RIG-I-like and NOD-like receptor signaling (BLU9931). Interrogation of public datasets revealed FGFR2 amplification, fusion or mutation in TNBC and other breast cancer subtypes, while FGFR4 overexpression and amplification occurred in all breast cancer subtypes and were associated with poor prognosis. Characterization of a PDO panel identified a luminal A PDO with high FGFR4 expression that was sensitive to BLU9931 treatment, further highlighting FGFR4 as a potential therapeutic target. Conclusions This work highlights how patient-derived models of human breast cancer provide powerful platforms for therapeutic target identification and analysis of drug action, and also the potential of specific FGFRs, including FGFR4, as targets for precision treatment.

Organoids are three‐dimensional self‐renewing and organizing clusters of cells that recapitulate the behavior and functionality of developed organs. Referred to as “organs in a dish,” organoids are invaluable biological models for disease modeling or drug screening. Currently, organoid culture commonly relies on an expensive and undefined tumor‐derived reconstituted basal membrane which hinders its application in high‐throughput screening, regenerative medicine, and diagnostics. Here, we introduce a novel engineered plant‐based nanocellulose hydrogel is introduced as a well‐defined and low‐cost matrix that supports organoid growth. Gels containing 0.1% nanocellulose fibers (99.9% water) are ionically crosslinked and present mechanical properties similar to the standard animal‐based matrix. The regulation of the osmotic pressure is performed by a salt‐free strategy, offering conditions for cell survival and proliferation. Cellulose nanofibers are functionalized with fibronectin‐derived adhesive sites to provide the required microenvironment for small intestinal organoid growth and budding. Comparative transcriptomic profiling reveals a good correlation with transcriptome‐wide gene expression pattern between organoids cultured in both materials, while differences are observed in stem cells‐specific marker genes. These hydrogels are tunable and can be combined with laminin‐1 and supplemented with insulin‐like growth factor (IGF‐1) to optimize the culture conditions. Nanocellulose hydrogel emerges as a promising matrix for the growth of organoids. Plant‐based nanocellulose hydrogel is introduced as a well‐defined and very low‐cost porous nanofibrous matrix that supports organoid growth. The mechanical, chemical, and biological properties of the gel are engineered to mimic the extracellular matrix (ECM), providing the required microenvironment for small intestinal organoid culture. This performant hydrogel is tunable with ECM‐derived components, emerging as a promising biomaterial for organoid systems.

Colorectal cancer stem cells have been proposed to drive disease progression, tumour recurrence and chemoresistance. However, studies ablating leucine rich repeat containing G protein-coupled receptor 5 (LGR5)-positive stem cells have shown that they are rapidly replenished in primary tumours. Following injury in normal tissue, LGR5+ stem cells are replaced by a newly defined, transient population of revival stem cells. We investigated whether markers of the revival stem cell population are present in colorectal tumours and how this signature relates to chemoresistance. We examined the expression of different stem cell markers in a cohort of patient-derived colorectal cancer organoids and correlated expression with sensitivity to 5-fluorouracil (5-FU) treatment. Our findings revealed that there was inter-tumour variability in the expression of stem cell markers. Clusterin (CLU), a marker of the revival stem cell population, was significantly enriched following 5-FU treatment and expression correlated with the level of drug resistance. Patient outcome data revealed that CLU expression is associated with both lower patient survival and an increase in disease recurrence. This suggests that CLU is a marker of drug resistance and may identify cells that drive colorectal cancer progression.

Silks from orb-weaving spiders are exceptionally tough, producing a model polymer for biomimetic fibre development. The mechanical properties of naturally spun silk threads from two species of Australian orb-weavers, and , were examined here in relation to overall thread diameter, the size and number of fibres within threads, and spider size. , the larger of the two species, had significantly tougher silk with higher strain capacity than its smaller congener, producing threads with average toughness of 150 MJ m , despite thread diameter, mean fibre diameter and number of fibres per thread not differing significantly between the two species. Within , smaller silk fibres were produced by larger spiders, yielding tougher threads. In contrast, while spider size was correlated with thread diameter in , there were no clear patterns relating to silk toughness, which suggests that the differences in properties between the silk of the two species arise through differing molecular structure. Our results support previous studies that found that the mechanical properties of silk differ between distantly related spider species, and extends on that work to show that the mechanical and physical properties of silk from more closely related species can also differ remarkably.

Gastrointestinal infections often induce epithelial damage that must be repaired for optimal gut function. While intestinal stem cells are critical for this regeneration process [R. C. van der Wath, B. S. Gardiner, A. W. Burgess, D. W. Smith, PLoS One 8, e73204 (2013); S. Kozar et al., Cell Stem Cell 13, 626–633 (2013)], how they are impacted by enteric infections remains poorly defined. Here, we investigate infection-mediated damage to the colonic stem cell compartment and how this affects epithelial repair and recovery from infection. Using the pathogen Clostridioides difficile, we show that infection disrupts murine intestinal cellular organization and integrity deep into the epithelium, to expose the otherwise protected stem cell compartment, in a TcdB-mediated process. Exposure and susceptibility of colonic stem cells to intoxication compromises their function during infection, which diminishes their ability to repair the injured epithelium, shown by altered stem cell signaling and a reduction in the growth of colonic organoids from stem cells isolated from infected mice. We also show, using both mouse and human colonic organoids, that TcdB from epidemic ribotype 027 strains does not require Frizzled 1/2/7 binding to elicit this dysfunctional stem cell state. This stem cell dysfunction induces a significant delay in recovery and repair of the intestinal epithelium of up to 2 wk post the infection peak. Our results uncover a mechanism by which an enteric pathogen subverts repair processes by targeting stem cells during infection and preventing epithelial regeneration, which prolongs epithelial barrier impairment and creates an environment in which disease recurrence is likely.

Inflammatory bowel disease (IBD) is secondary to an abnormal immune response to the microbiota. To study this, models of host-microbe interactions that represent mucosal bacterial communities and inter-patient diversity are required. Human intestinal organoids (HIOs) are an established model to investigate epithelial responses. Here, we describe a technique of culturing bacteria directly from the sites of inflammation in IBD, while simultaneously sampling host tissue. We generated HIOs from a cohort of newly diagnosed paediatric IBD patients, without confounding treatments or comorbidities, and explored their response to site-specific bacteria. A unique biobank of matched HIOs and cultured mucosa-attached bacteria was established from 27 paediatric patients. Transcriptional profiling revealed differential gene expression between control and IBD-derived organoids. We used microinjection to introduce bacteria to the apical surface of the epithelium, to determine the effect of bacteria on host epithelial cells. We measured survival and growth of bacteria within the HIOs and tested several related bacterial isolates for their impact on the epithelium. An isolate from a control patient stimulated inflammatory signalling pathways but this was not observed in response to a closely related isolate originating from an IBD patient. This study demonstrates the feasibility of isolating bacteria and generating organoids from the same biopsy tissue, to explore personalised host-microbe interactions. The microinjections, while labour-intensive, demonstrate that closely related bacteria can induce very different epithelial responses, with downstream implications for immune response. This highlights the importance of understanding host-microbe interactions in a strain- and site-specific manner and developing techniques for personalised microbiome-based therapeutics.

Silks from orb-weaving spiders are exceptionally tough, producing a model polymer for biomimetic fibre development. The mechanical properties of naturally spun silk threads from two species of Australian orb-weavers, Nephila pilipes and Nephilaplumipes, were examined here in relation to overall thread diameter, the size and number of fibres within threads, and spider size. N. pilipes, the larger of the two species, had significantly tougher silk with higher strain capacity than its smaller congener, producing threads with average toughness of 150 MJ m-3, despite thread diameter, mean fibre diameter and number of fibres per thread not differing significantly between the two species. Within N. pilipes, smaller silk fibres were produced by larger spiders, yielding tougher threads. In contrast, while spider size was correlated with thread diameter in N. plumipes, there were no clear patterns relating to silk toughness, which suggests that the differences in properties between the silk of the two species arise through differing molecular structure. Our results support previous studies that found that the mechanical properties of silk differ between distantly related spider species, and extends on that work to show that the mechanical and physical properties of silk from more closely related species can also differ remarkably.Silks from orb-weaving spiders are exceptionally tough, producing a model polymer for biomimetic fibre development. The mechanical properties of naturally spun silk threads from two species of Australian orb-weavers, Nephila pilipes and Nephilaplumipes, were examined here in relation to overall thread diameter, the size and number of fibres within threads, and spider size. N. pilipes, the larger of the two species, had significantly tougher silk with higher strain capacity than its smaller congener, producing threads with average toughness of 150 MJ m-3, despite thread diameter, mean fibre diameter and number of fibres per thread not differing significantly between the two species. Within N. pilipes, smaller silk fibres were produced by larger spiders, yielding tougher threads. In contrast, while spider size was correlated with thread diameter in N. plumipes, there were no clear patterns relating to silk toughness, which suggests that the differences in properties between the silk of the two species arise through differing molecular structure. Our results support previous studies that found that the mechanical properties of silk differ between distantly related spider species, and extends on that work to show that the mechanical and physical properties of silk from more closely related species can also differ remarkably.