Lower respiratory tract infection admissions and deaths among children under 5 years in public sector facilities in the Western Cape Province, South Africa, before and during the COVID-19 pandemic (2019 - 2021)

BACKGROUND

The COVID-19 pandemic resulted in the implementation of strict public health and social measures (PHSMs) (including mobility restrictions, social distancing, mask-wearing and hand hygiene), limitations on non-essential healthcare services, and public fear of COVID-19 infection, all of which potentially affected transmission and healthcare use for other diseases such as lower respiratory tract infections (LRTIs).

OBJECTIVE

To determine changes in LRTI hospital admissions and in-facility mortality in children aged <5 years in the Western Cape Province during the pandemic.

METHODS

We conducted a retrospective analysis of LRTI admissions and in-facility deaths from January 2019 to November 2021. We estimated changes in rates and trends of LRTI admissions during the pandemic compared with pre-pandemic period using interrupted time series analysis, adjusting for key characteristics.

RESULTS

There were 36 277 children admitted for LRTIs during the study period, of whom 58% were male and 51% were aged 28 days - 1 year. COVID-19 restrictions were associated with a 13% step reduction in LRTI admissions compared with the pre-COVID-19 period (incidence rate ratio (IRR) 0.87, 95% confidence interval (CI)) 0.80 - 0.94). The average LRTI admission trend increased on average by 2% per month during the pandemic (IRR 1.02, 95% CI 1.02 - 1.04).

CONCLUSIONS

The COVID-19 surges and their associated measures were linked to declining LRTI admissions and in-facility deaths, likely driven by a combination of reduced infectious disease transmission and reduced use of healthcare services, with effects diminishing over time. These findings may inform future pandemic response policies.

Leptomeningeal Neural Organoid (LMNO) Fusions as Models to Study Meninges-Brain Signaling

Neural organoids derived from human induced pluripotent stem cells (iPSCs) provide a model to study the earliest stages of human brain development, including neurogenesis, neural differentiation, and synaptogenesis. However, neural organoids lack supportive tissues and some non-neural cell types that are key regulators of brain development. Neural organoids have instead been co-cultured with non-neural structures and cell types to promote their maturation and model interactions with neuronal cells. One structure that does not form de novo with neural organoids is the meninges, a tri-layered structure that surrounds the CNS and secretes key signaling molecules required for mammalian brain development. Most studies of meninges-brain signaling have been performed in mice or using two-dimensional (2D) cultures of human cells, the latter not recapitulating the architecture and cellular diversity of the tissue. To overcome this, we developed a co-culture system of neural organoids generated from human iPSCs fused with fetal leptomeninges from mice with fluorescently labeled meninges (Col1a1-GFP). These proof-of-concept studies test the stability of the different cell types in the leptomeninges (fibroblast and macrophage) and the fused brain organoid (progenitor and neuron), as well as the interface between the organoid and meningeal tissue. We test the longevity of the fusion pieces after 30 days and 60 days in culture, describe best practices for preparing the meninges sample prior to fusion, and examine the feasibility of single or multiple meninges pieces fused to a single organoid. We discuss potential uses of the current version of the LMNO fusion model and opportunities to improve the system.

Leptomeningeal Neural Organoid (LMNO) Fusions as Models to Study Meninges-Brain Signaling

Neural organoids derived from human induced pluripotent stem cells (iPSCs) provide a model to study the earliest stages of human brain development, including neurogenesis, neural differentiation, and synaptogenesis. However, neural organoids lack supportive tissues and some non-neural cell types that are key regulators of brain development. Neural organoids have instead been co-cultured with non-neural structures and cell types to promote their maturation and model interactions with neuronal cells. One structure that does not form de novo with neural organoids is the meninges, a tri-layered structure that surrounds the CNS and secretes key signaling molecules required for mammalian brain development. Most studies of meninges-brain signaling have been performed in mice or using two-dimensional (2D) cultures of human cells, the latter not recapitulating the architecture and cellular diversity of the tissue. To overcome this, we developed a co-culture system of neural organoids generated from human iPSCs fused with fetal leptomeninges from mice with fluorescently labeled meninges (Col1a1-GFP). These proof-of-concept studies test the stability of the different cell types in the leptomeninges (fibroblast and macrophage) and the fused brain organoid (progenitor and neuron), as well as the interface between the organoid and meningeal tissue. We test the longevity of the fusion pieces after 30 days and 60 days in culture, describe best practices for preparing the meninges sample prior to fusion, and examine the feasibility of single or multiple meninges pieces fused to a single organoid. We discuss potential uses of the current version of the LMNO fusion model and opportunities to improve the system.

Meningeal origins and dynamics of perivascular fibroblast development on the mouse cerebral vasculature

Perivascular fibroblasts (PVFs) are a fibroblast-like cell type that reside on large-diameter blood vessels in the adult meninges and central nervous system (CNS). PVFs contribute to fibrosis following injury but their homeostatic functions are not defined. PVFs were previously shown to be absent from most brain regions at birth and are only detected postnatally within the cerebral cortex. However, the origin, timing and cellular mechanisms of PVF development are not known. We used Col1a1-GFP and Col1a2-CreERT2 transgenic mice to track PVF development postnatally. Using lineage tracing and in vivo imaging we show that brain PVFs originate from the meninges and are first seen on parenchymal cerebrovasculature at postnatal day (P) 5. After P5, PVF coverage of the cerebrovasculature expands via local cell proliferation and migration from the meninges. Finally, we show that PVFs and perivascular macrophages develop concurrently. These findings provide the first complete timeline for PVF development in the brain, enabling future work into how PVF development is coordinated with cell types and structures in and around the perivascular spaces to support normal CNS vascular function.

Formation and function of the meningeal arachnoid barrier around the developing mouse brain

The arachnoid barrier, a component of the blood-cerebrospinal fluid barrier (B-CSFB) in the meninges, is composed of epithelial-like, tight-junction-expressing cells. Unlike other central nervous system (CNS) barriers, its' developmental mechanisms and timing are largely unknown. Here, we show that mouse arachnoid barrier cell specification requires the repression of Wnt-β-catenin signaling and that constitutively active β-catenin can prevent its formation. We also show that the arachnoid barrier is functional prenatally and, in its absence, a small molecular weight tracer and the bacterium group B Streptococcus can cross into the CNS following peripheral injection. Acquisition of barrier properties prenatally coincides with the junctional localization of Claudin 11, and increased E-cadherin and maturation continues after birth, where postnatal expansion is marked by proliferation and re-organization of junctional domains. This work identifies fundamental mechanisms that drive arachnoid barrier formation, highlights arachnoid barrier fetal functions, and provides novel tools for future studies on CNS barrier development.

Meningeal origins and dynamics of perivascular fibroblast development on the mouse cerebral vasculature

Perivascular fibroblasts (PVFs) are a fibroblast-like cell type that reside on large-diameter blood vessels in the adult meninges and central nervous system (CNS). PVFs drive fibrosis following injury but their homeostatic functions are not well detailed. In mice, PVFs were previously shown to be absent from most brain regions at birth and are only detected postnatally within the cerebral cortex. However, the origin, timing, and cellular mechanisms of PVF development are not known. We used Col1a1-GFP and Col1a2-CreERT transgenic mice to track PVF developmental timing and progression in postnatal mice. Using a combination of lineage tracing and in vivo imaging we show that brain PVFs originate from the meninges and are first seen on parenchymal cerebrovasculature at postnatal day (P)5. After P5, PVF coverage of the cerebrovasculature rapidly expands via mechanisms of local cell proliferation and migration from the meninges, reaching adult levels at P14. Finally, we show that PVFs and perivascular macrophages (PVMs) develop concurrently along postnatal cerebral blood vessels, where the location and depth of PVMs and PVFs highly correlate. These findings provide the first complete timeline for PVF development in the brain, enabling future work into how PVF development is coordinated with cell types and structures in and around the perivascular spaces to support normal CNS vascular function.

Summary

Brain perivascular fibroblasts migrate from their origin in the meninges and proliferate locally to fully cover penetrating vessels during postnatal mouse development.

Development and operation of the defence COVID-19 lab as a SARS-CoV-2 diagnostic screening capability for UK military personnel

BACKGROUND

In the face of the COVID-19 pandemic, the Defence Science and Technology Laboratory (Dstl) and Defence Pathology combined to form the Defence Clinical Lab (DCL), an accredited (ISO/IEC 17025:2017) high-throughput SARS-CoV-2 PCR screening capability for military personnel.

LABORATORY STRUCTURE AND RESOURCE

The DCL was modular in organisation, with laboratory modules and supporting functions combining to provide the accredited SARS-CoV-2 (envelope (E)-gene) PCR assay. The DCL was resourced by Dstl scientists and military clinicians and biomedical scientists.

LABORATORY RESULTS

Over 12 months of operation, the DCL was open on 289 days and tested over 72 000 samples. Six hundred military SARS-CoV-2-positive results were reported with a median E-gene quantitation cycle (Cq) value of 30.44. The lowest Cq value for a positive result observed was 11.20. Only 64 samples (0.09%) were voided due to assay inhibition after processing started.

CONCLUSIONS

Through a sustained effort and despite various operational issues, the collaboration between Dstl scientific expertise and Defence Pathology clinical expertise provided the UK military with an accredited high-throughput SARS-CoV-2 PCR test capability at the height of the COVID-19 pandemic. The DCL helped facilitate military training and operational deployments contributing to the maintenance of UK military capability. In offering a bespoke capability, including features such as testing samples in unit batches and oversight by military consultant microbiologists, the DCL provided additional benefits to the UK Ministry of Defence that were potentially not available from other SARS-CoV-2 PCR laboratories. The links between Dstl and Defence Pathology have also been strengthened, benefitting future research activities and operational responses.

Creating and Sustaining Service Industry Relationships and Families: Theorizing How Personal Workplace Relationships Both Build Community and Perpetuate Organizational Violence

Service industry workers experience challenging labor conditions in the United States, including pay below the minimum wage, expected emotional labor, and harassment. Additionally, in part because they work long shifts in high stress environments in restaurants and bars, many build and form personal workplace relationships (PWRs). In 2021, we interviewed 38 service industry workers and managers during the COVID-19 pandemic where we examined occupational challenges they faced in the state of Texas, USA. Through our interpretive research, this essay showcases our inductive findings on how service industry workers and managers utilize communication to create and sustain PWRs. We identified how some PWRs are sustained through a unique form of occupational identification that cultivates a "service industry family", which we term familial personal workplace relationships (familial PWRs). This extends past organizational communication scholarship on family to consider occupational identification. Furthermore, our research reveals that while PWRs may build communities through care and support, they also perpetuate organizational violence, like sexual harassment and bullying.

Techniques for visualizing fibroblast-vessel interactions in the developing and adult CNS

Significance: Fibroblasts are found associated with blood vessels in various locations across the central nervous system (CNS): in the meninges, the choroid plexus, and in the parenchyma within perivascular spaces. CNS fibroblasts have been characterized using transcriptional profiling and a Col1a1-GFP mouse line used to identify CNS fibroblasts in vivo; however, we still know very little regarding their functions and identity. Aim: Current methods for visualizing CNS fibroblasts are lacking and, in particular, prevent adequate assessment of fibroblast-vessel interactions. We aimed to develop new ways to visualize CNS fibroblasts in greater detail. Approach: Here, we describe methods for whole mount visualization of meningeal and choroid plexus fibroblasts, and CUBIC optical tissue clearing methods for visualization of parenchymal vessel-associated fibroblasts. Results: We show that these methods can be used for visualization of vessel-fibroblast interactions in these CNS structures and provide significant improvement over traditional sectioning and staining methods. In addition, we can combine these techniques with immunohistochemistry methods for labeling different cell types in the meninges and blood vasculature as well as EdU-based cell proliferation assays. Conclusions: We expect these methods will advance studies of CNS fibroblast development and functions in homeostasis, injury, and disease.

709 IMPACT ON HEALTHCARE UTILISATION OF A GENERAL PRACTITIONER-LED MODEL OF CARE FOR PATIENTS WITH FRAILTY

Introduction

Primary care has a significant role to play in the identification and management of frailty. MidMed is a new dedicated GP-led service developed by a large practice in Midlothian for patients living at home with moderate or severe frailty. MidMed comprises a full-time GP performing a comprehensive geriatric assessment (CGA) adapted for primary care. Patients receive direct access to all appointments with the named GP. The aim of this study was to assess the impact of MidMed on healthcare utilisation in this patient group.

Methods

Patients with moderate or severe frailty at the MidMed practice were identified by the electronic Frailty Index (&gt;0.24). After 16 months, patients who had been accepted into MidMed (MidMed group) were compared with those yet to be enrolled and who continued to receive usual care (non-MidMed group). Routinely collected data were used to identify outcomes including unscheduled hospital admissions, primary care consultations, continuity of care, outpatient attendances and mortality. Adjusted rate ratios were estimated using regression models.

Results

510 patients with moderate or severe frailty were identified (290 in MidMed, 220 in non-MidMed). Patients in each group were just as likely to have at least one hospital admission per year but those in MidMed had a reduced risk of further hospital admission compared to the non-MidMed group (adjusted RR 0.46 [95%CI 0.30–0.71]). MidMed was also associated with statistically significant higher usage of primary care (adjusted RR 1.52, [95%CI, 1.30–1.75]) and better continuity of care. There was no difference in mortality or the number of outpatient appointments when adjusted for co-variates.

Conclusion

A GP-led service for frailty is associated with lower risk of hospital readmission and improved continuity of care. Further studies are now required to better understand why use of such primary care services increase and whether this changes over time.

Corrigendum: Living on the Edge of the CNS: Meninges Cell Diversity in Health and Disease

[This corrects the article DOI: 10.3389/fncel.2021.703944.].

Living on the Edge of the CNS: Meninges Cell Diversity in Health and Disease

The meninges are the fibrous covering of the central nervous system (CNS) which contain vastly heterogeneous cell types within its three layers (dura, arachnoid, and pia). The dural compartment of the meninges, closest to the skull, is predominantly composed of fibroblasts, but also includes fenestrated blood vasculature, an elaborate lymphatic system, as well as immune cells which are distinct from the CNS. Segregating the outer and inner meningeal compartments is the epithelial-like arachnoid barrier cells, connected by tight and adherens junctions, which regulate the movement of pathogens, molecules, and cells into and out of the cerebral spinal fluid (CSF) and brain parenchyma. Most proximate to the brain is the collagen and basement membrane-rich pia matter that abuts the glial limitans and has recently be shown to have regional heterogeneity within the developing mouse brain. While the meninges were historically seen as a purely structural support for the CNS and protection from trauma, the emerging view of the meninges is as an essential interface between the CNS and the periphery, critical to brain development, required for brain homeostasis, and involved in a variety of diseases. In this review, we will summarize what is known regarding the development, specification, and maturation of the meninges during homeostatic conditions and discuss the rapidly emerging evidence that specific meningeal cell compartments play differential and important roles in the pathophysiology of a myriad of diseases including: multiple sclerosis, dementia, stroke, viral/bacterial meningitis, traumatic brain injury, and cancer. We will conclude with a list of major questions and mechanisms that remain unknown, the study of which represent new, future directions for the field of meninges biology.

Single-Cell Transcriptomic Analyses of the Developing Meninges Reveal Meningeal Fibroblast Diversity and Function

The meninges are a multilayered structure composed of fibroblasts, blood and lymphatic vessels, and immune cells. Meningeal fibroblasts secrete a variety of factors that control CNS development, yet strikingly little is known about their heterogeneity or development. Using single-cell sequencing, we report distinct transcriptional signatures for fibroblasts in the embryonic dura, arachnoid, and pia. We define new markers for meningeal layers and show conservation in human meninges. We find that embryonic meningeal fibroblasts are transcriptionally distinct between brain regions and identify a regionally localized pial subpopulation marked by the expression of μ-crystallin. Developmental analysis reveals a progressive, ventral-to-dorsal maturation of telencephalic meninges. Our studies have generated an unparalleled view of meningeal fibroblasts, providing molecular profiles of embryonic meningeal fibroblasts by layer and yielding insights into the mechanisms of meninges development and function.

Natural Selection Towards Wild-Type in Composite Cross Populations of Winter Wheat

Most of our crops are grown in monoculture with single genotypes grown over wide acreage. An alternative approach, where segregating populations are used as crops, is an exciting possibility, but outcomes of natural selection upon this type of crop are not well understood. We tracked allelic frequency changes in evolving composite cross populations of wheat grown over 10 generations under organic and conventional farming. At three generations, each population was genotyped with 19 SSR and 8 SNP markers. The latter were diagnostic for major functional genes. Gene diversity was constant at SSR markers but decreased over time for SNP markers. Population differentiation between the four locations could not be detected, suggesting that organic vs. non-organic crop management did not drive allele frequency changes. However, we did see changes for genes controlling plant height and phenology in all populations independently and consistently. We interpret these changes as the result of a consistent natural selection towards wild-type. Independent selection for alleles that are associated with plant height suggests that competition for light was central, resulting in the predominance of stronger intraspecific competitors, and highlighting a potential trade-off between individual and population performance.

Is there sufficient Ensifer and Rhizobium species diversity in UK farmland soils to support red clover (Trifolium pratense), white clover (T. repens), lucerne (Medicago sativa) and black medic (M. lupulina)?

Rhizobia play important roles in agriculture owing to their ability to fix nitrogen through a symbiosis with legumes. The specificity of rhizobia-legume associations means that underused legume species may depend on seed inoculation with their rhizobial partners. For black medic (Medicago lupulina) and lucerne (Medicago sativa) little is known about the natural prevalence of their rhizobial partner Ensifer meliloti in UK soils, so that the need for inoculating them is unclear. We analysed the site-dependence of rhizobial seed inoculation effects on the subsequent ability of rhizobial communities to form symbioses with four legume species (Medicago lupulina, M. sativa, Trifolium repens and T. pratense). At ten organic farms across the UK, a species-diverse legume based mixture (LBM) which included these four species was grown. The LBM seed was inoculated with a mix of commercial inocula specific for clover and lucerne. At each site, soil from the LBM treatment was compared to the soil sampled prior to the sowing of the LBM (the control). From each site and each of the two treatments, a suspension of soils was applied to seedlings of the four legume species and grown in axenic conditions for six weeks. Root nodules were counted and their rhizobia isolated. PCR and sequencing of a fragment of the gyrB gene from rhizobial isolates allowed identification of strains. The number of nodules on each of the four legume species was significantly increased when inoculated with soil from the LBM treatment compared to the control. Both the proportion of plants forming nodules and the number of nodules formed varied significantly by site, with sites significantly affecting the Medicago species but not the Trifolium species. These differences in nodulation were broadly reflected in plant biomass where site and treatment interacted; at some sites there was a significant advantage from inoculation with the commercial inoculum but not at others. In particular, this study has demonstrated the commercial merit of inoculation of lucerne with compatible rhizobia.

Label-invariant models for the analysis of meta-epidemiological data

Rich meta‐epidemiological data sets have been collected to explore associations between intervention effect estimates and study‐level characteristics. Welton et al proposed models for the analysis of meta‐epidemiological data, but these models are restrictive because they force heterogeneity among studies with a particular characteristic to be at least as large as that among studies without the characteristic. In this paper we present alternative models that are invariant to the labels defining the 2 categories of studies. To exemplify the methods, we use a collection of meta‐analyses in which the Cochrane Risk of Bias tool has been implemented. We first investigate the influence of small trial sample sizes (less than 100 participants), before investigating the influence of multiple methodological flaws (inadequate or unclear sequence generation, allocation concealment, and blinding). We fit both the Welton et al model and our proposed label‐invariant model and compare the results. Estimates of mean bias associated with the trial characteristics and of between‐trial variances are not very sensitive to the choice of model. Results from fitting a univariable model show that heterogeneity variance is, on average, 88% greater among trials with less than 100 participants. On the basis of a multivariable model, heterogeneity variance is, on average, 25% greater among trials with inadequate/unclear sequence generation, 51% greater among trials with inadequate/unclear blinding, and 23% lower among trials with inadequate/unclear allocation concealment, although the 95% intervals for these ratios are very wide. Our proposed label‐invariant models for meta‐epidemiological data analysis facilitate investigations of between‐study heterogeneity attributable to certain study characteristics.

Elevated temperature drives a shift from selfing to outcrossing in the insect-pollinated legume, faba bean (Vicia faba)

Climate change can threaten the reproductive success of plants, both directly, through physiological damage during increasingly extreme weather events, and indirectly, through disruption of plant-pollinator interactions. To explore how plant-pollinator interactions are modified by extreme weather, we exposed faba bean (Vicia faba) plants to elevated temperature for 5 d during flowering, simulating a heatwave. We then moved the plants to flight cages with either bumblebees or no pollinators, or to two field sites, where plants were enclosed in mesh bags or pollinated by wild insect communities. We used a morphological marker to quantify pollen movement between experimental plants. There was a substantial increase in the level of outcrossing by insect pollinators following heat stress. Proportion outcrossed seed increased from 17 % at control temperature, to 33 % following heat stress in the flight cages, and from 31 % to 80 % at one field site, but not at the other (33 % to 32 %). Abiotic stress can dramatically shift the relative contributions of cross- and self-pollination to reproduction in an insect pollinated plant. The resulting increases in gene flow have broad implications for genetic diversity and functioning of ecosystems, and may increase resilience by accelerating the selection of more stress-tolerant genotypes.

Effectiveness of chemical pleurodesis in spontaneous pneumothorax recurrence prevention: a systematic review

Objectives

Spontaneous pneumothorax is a common pathology. International guidelines suggest pleurodesis for non-resolving air leak or recurrence prevention at second occurrence. This study comprehensively reviews the existing literature regarding chemical pleurodesis efficacy.

Design

We systematically reviewed the literature to identify relevant randomised controlled trials (RCTs), case–control studies and case series. We described the findings of these studies and tabulated relative recurrence rates or ORs (in studies with control groups). Meta-analysis was not performed due to substantial clinical heterogeneity.

Results

Of 560 abstracts identified by our search strategy, 50 were included in our systematic review following screening. Recurrence rates in patients with chest tube drainage only were between 26.1% and 50.1%. Thoracoscopic talc poudrage (four studies (n=249)) provided recurrence rates of between 2.5% and 10.2% with the only RCT suggesting an OR of 0.10 compared with drainage alone. In comparison, talc administration during video-assisted thoracic surgery (VATS) from eight studies (n=2324) recurrence was between 0.0% and 3.2%, but the RCT did not demonstrate a significant difference compared with bleb/bullectomy alone. Minocycline appears similarly effective post-VATS (recurrence rates 0.0–2.9%). Prolonged air leak and recurrence prevention using tetracycline via chest drain (n=726) is likely to provide recurrence rates between 13.0% and 33.3% and autologous blood patch pleurodesis (n=270) between 15.6% and 18.2%.

Conclusions

Chemical pleurodesis postsurgical treatment or via thoracoscopy appears to be most effective. Evidence for definitive success rates of each agent is limited by the small number of randomised trials or other comparative studies.

Effect of breadmaking process on in vitro gut microbiota parameters in irritable bowel syndrome

A variety of foods have been implicated in symptoms of patients with Irritable Bowel Syndrome (IBS) but wheat products are most frequently cited by patients as a trigger. Our aim was to investigate the effects of breads, which were fermented for different lengths of time, on the colonic microbiota using in vitro batch culture experiments. A set of in vitro anaerobic culture systems were run over a period of 24 h using faeces from 3 different IBS donors (Rome Criteria-mainly constipated) and 3 healthy donors. Changes in gut microbiota during a time course were identified by fluorescence in situ hybridisation (FISH), whilst the small-molecular weight metabolomic profile was determined by NMR analysis. Gas production was separately investigated in non pH-controlled, 36 h batch culture experiments. Numbers of bifidobacteria were higher in healthy subjects compared to IBS donors. In addition, the healthy donors showed a significant increase in bifidobacteria (P<0.005) after 8 h of fermentation of a bread produced using a sourdough process (type C) compared to breads produced with commercial yeasted dough (type B) and no time fermentation (Chorleywood Breadmaking process) (type A). A significant decrease of δ-Proteobacteria and most Gemmatimonadetes species was observed after 24 h fermentation of type C bread in both IBS and healthy donors. In general, IBS donors showed higher rates of gas production compared to healthy donors. Rates of gas production for type A and conventional long fermentation (type B) breads were almost identical in IBS and healthy donors. Sourdough bread produced significantly lower cumulative gas after 15 h fermentation as compared to type A and B breads in IBS donors but not in the healthy controls. In conclusion, breads fermented by the traditional long fermentation and sourdough are less likely to lead to IBS symptoms compared to bread made using the Chorleywood Breadmaking Process.

Term and preterm labour are associated with distinct microbial community structures in placental membranes which are independent of mode of delivery

Infection is considered a possible trigger for preterm labour, supported by evidence showing the presence of bacteria in the placenta and placental membranes from preterm births. In this study, 16S rDNA pyrosequencing was used to identify bacteria in placental membranes. Caesarean sections and vaginal deliveries at term were found to harbour common genera. Mycoplasma hominis, Aerococcus christensenii, Gardnerella vaginalis and Fusobacterium nucleatum were either only present in preterm membranes or in greater abundance than at term. These data support previous studies that used either targeted qPCR or broad-range 16S rDNA PCR and cloning but not a recent microbiome analysis of placental tissue using high-throughput sequencing.

Function of mGlu1 receptors in the modulation of nociceptive processing in the thalamus

As postsynaptic metabotropic subtype 1 (mGlu1) receptors are present in the thalamus, we have investigated the effect of potentiating and antagonising mGlu1 receptors on responses of thalamic neurones to noxious sensory stimulation. Extracellular recordings were made in vivo with multi-barrel iontophoretic electrodes from single neurones in the thalamus of urethane-anaesthetised rats. Responses to iontophoretic applications of the Group I mGlu agonist 3,5-dihydroxy-phenylglycine (DHPG) were selectively potentiated by co-application of the mGlu1 positive allosteric modulator Ro67-4853, whereas they were selectively reduced upon co-application of the mGlu1 receptor orthosteric antagonist LY367385. This indicates that thalamic DHPG responses are mediated primarily via mGlu1 receptors, consistent with the high postsynaptic levels of this receptor in the thalamus. Furthermore, potentiation of DHPG responses by Ro67-4853 were greater when the initial DHPG response was of a low magnitude. Ro67-4853 also potentiated responses of thalamic neurones to noxious thermal stimulation, whilst having little effect on the baseline activity of nociceptive neurones. By contrast, nociceptive responses were reduced by LY367385. In a further series of experiments we found that inactivation of somatosensory cortex by cooling resulted in a reduction of thalamic nociceptive responses. These results underline the importance of mGlu1 receptors in the processing of sensory information in the thalamus, particularly with respect to nociceptive responses. Furthermore, the involvement of mGlu1 receptors may reflect the activity of descending cortico-thalamic afferents.

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Pharmacological potentiation of mGlu1 receptors enhances nociceptive responses of thalamic neurones.

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Antagonism of mGlu1 receptors reduces nociceptive responses of thalamic neurones.

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Inactivation of somatosensory cortex reduces nociceptive responses of thalamic neurones.

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This suggests a role for mGlu1 receptors and cortico-thalamic pathways in nociceptive processing.

LOS oligosaccharide modification enhances dendritic cell responses to meningococcal native outer membrane vesicles expressing a non-toxic lipid A

Outer membrane vesicles (OMV) are released by many bacteria, and contain immunogenic antigens in addition to harmful inflammatory factors, like lipopolysaccharides. Chemically detoxified OMV have been used in vaccines against Neisseria meningitidis (Nm); however, little is known about their interaction with antigen presenting cells. In this study, we investigated the interaction of Nm OMV with human dendritic cells (DC) to gain further understanding of their biological activity. We engineered a novel serogroup B Nm that is unencapsulated (siaD), expresses pentacylated lipid A (lpxL1), hence conferring reduced toxicity, and expresses an lgtB oligosaccharide structure designed to target OMV to DC via DC-SIGN. We show that the lgtB moiety is critical for internalization of NOMV by DC. Furthermore, the lgtB moiety significantly enhances DC maturation, IL-10 and IL-23 production in the presence of a pentacylated lipid A. While different DC phenotypes were observed for each NOMV, this had little effect on Th1 and Th2 cell differentiation; however, lgtBsignificantly increased Th17 cell expansion in the presence of pentacylated lipid A. We believe that lpxL1/lgtB NOMV should be considered further as a vaccine vector, particularly considering the importance of lgtB in antigen uptake and further human studies on antigen-specific responses should be considered.

Quantifying the relationship between temperature regulation in the ear and floret development stage in wheat (Triticum aestivum L.) under heat and drought stress

Thermal imaging is a valuable tool for the clarification of gas exchange dynamics between a plant and its environment. The presence of stomata in wheat (Triticum aestivum L.) glumes and awns offers an opportunity to assess the photosynthetic activity of ears up to and during flowering. Knowledge of the spatial and temporal thermodynamics of the wheat ear may provide insight into interactions between floret developmental stage (FDS), temperature depression (TD) and ambient environment, with potential to use these as high-throughput screening tools for breeders. A controlled environment study was conducted using six spring wheat genotypes of the elite recombinant inbred line Seri-Babax. Average ear temperature was recorded using a hand-held infrared camera and gas exchange was measured by enclosing ears in a custom-built cuvette. FDS was monitored and recorded daily throughout the study. Plants were grown in pots and exposed to a combination of two temperature and two water regimes. In the studied wheat lines, TD varied from 0.1°C to 0.6°C according to the level of stress imposed. The results indicated that TD does not occur at FDS F3, the peak of active flowering, but during the stages before pollen release and stigma maturity (F1-F2). These findings suggest that ear temperature during the early stages of anthesis, before pollen release and full extension of the stigma, are likely to be the most relevant for identifying heat stress tolerant genotypes.

Women's preferences for testing and management of sexually transmitted infections among low-income New York City family planning clients

Summary

High prevalence of chlamydia in the USA persists despite efforts to annually screen women under the age of 26. Tailoring sexually transmitted infection (STI) services to client preferences may strengthen existing programmes. We report women's preferences for STI services from a family planning clinic in New York City serving low-income women. Seventy-eight percent (995/1275) of eligible women participated, with a mean age of 26 (SD±7). Ninety-one percent self-identified as Latina. Nineteen percent reported a past STI. Women preferred self-collection (65%) for testing to a speculum exam (20%); 15% had no preference. Women with a previous STI were more likely to prefer a pelvic exam to women with no previous STI (50% versus 32%, P < 0.01). Nearly all women (94%) preferred informing a sex partner about a positive STI test themselves, but 88% were willing to bring expedited partner therapy to a partner. Women were more likely to prefer third party partner notification if their last partner was casual rather than a main partner (14% versus 3%, respectively, P < 0.01). Forty-four percent of participants worried about physical violence after partner notification. Self-collecting specimens for screening was widely acceptable. Partner notification strategies should be based on understanding partnership status, including fears of violence.

Responses of primate LGN cells to moving stimuli involve a constant background modulation by feedback from area MT

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We investigated the influence of area MT feedback on LGN cell responses to visual stimuli.

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We used focal GABA micro-iontophoresis to reversibly block area MT cell responses.

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Inactivating area MT feedback produced clear and reversible changes in LGN cell responses.

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Effects were observed across magno, parvo and koniocellular LGN cell types.

The feedback connections from the cortical middle temporal (MT) motion area, to layer 6 of the primary visual cortex (V1), have the capacity to drive a cascaded feedback influence from the layer 6 cortico-geniculate cells back to the lateral geniculate nucleus (LGN) relay cells. This introduces the possibility of a re-entrant motion signal affecting the relay of the retinal input through the LGN to the visual cortex. The question is whether the response of LGN cells to moving stimuli involves a component derived from this feedback. By producing a reversible focal pharmacological block of the activity of an MT direction column we show the presence of such an influence from MT on the responses of magno, parvo and koniocellular cells in the macaque LGN. The pattern of effect in the LGN reflects the direction bias of the MT location inactivated. This suggests a moving stimulus is captured by iterative interactions in the circuit formed by visual cortical areas and visual thalamus.

Asynchronous flowering and within-plant flowering diversity in wheat and the implications for crop resilience to heat

BACKGROUND AND AIMS

Self-pollination dominates in wheat, with a small level of out-crossing due to flowering asynchrony and male sterility. However, the timing and synchrony of male and female flowering in wheat is a crucial determinant of seed set and may be an important factor affecting gene flow and resilience to climate change. Here, a methodology is presented for assessing the timing and synchrony of flowering in wheat, Triticum aestivum.

METHODS

From the onset of flowering until the end of anthesis, the anther and stigma activity of each floret was assessed on the first five developing ears in potted plants grown under ambient conditions and originating from 'Paragon' or 'Spark-Rialto' backgrounds. At harvest maturity, seed presence, size and weight was recorded for each floret scored.

KEY RESULTS AND CONCLUSIONS

The synchrony between pollen dehiscence and stigma collapse within a flower was dependent on its relative position in a spike and within a floret. Determined on the basis of synchrony within each flower, the level of pollination by pollen originating from other flowers reached approx. 30 % and did not change throughout the duration of flowering. A modelling exercise parameterized by flowering observations indicated that the temporal and spatial variability of anther activity within and between spikes may influence the relative resilience of wheat to sudden, extreme climatic events which has direct relevance to predicted future climate scenarios in the UK.

Human dendritic cell culture and bacterial infection

Dendritic cells (DC) play a key role in the development of natural immunity to microbes. The DC form a bridge between the innate and adaptive immune system by providing key instructions particularly to antigen naïve T-cells. The interaction of DC with T lymphocytes involves three signals: (1) antigen processing and presentation in context of MHC Class I and/or II, (2) expression of T cell co-stimulatory molecules, and (3) cytokine production. Studying the interactions of DCs with specific pathogens allows for better understanding of how protective immunity is generated, and may be particularly useful for assessing vaccine components. In this chapter, we describe methods to generate human monocyte-derived DCs and assess their maturation, activation, and function, using interaction with the gram-negative bacterial pathogen Neisseria meningitidis as a model.

Potentiation of sensory responses in ventrobasal thalamus in vivo via selective modulation of mGlu1 receptors with a positive allosteric modulator

Metabotropic glutamate subtype 1 (mGlu1) receptor is thought to play a role in synaptic responses in thalamic relay nuclei. The aim of this study was to evaluate the positive allosteric modulator (PAM) Ro67-4853 as a tool to modulate thalamic mGlu1 receptors on single thalamic neurones in vivo. Ro67-4853, applied by iontophoresis onto ventrobasal thalamus neurones of urethane-anaesthetised rats, selectively enhanced responses to the agonist (S)-3,5-dihydroxy-phenylglycine (DHPG), an effect consistent with mGlu1 potentiation. The PAM was also able to enhance maintained responses to 10 Hz trains of sensory stimulation of the vibrissae, but had little effect on responses to single sensory stimuli. Thus Ro67-4853 appears to be a highly selective tool that can be useful in investigating how mGlu1 receptor potentiation can alter neural processing in vivo. Our results show the importance of mGlu1 in sensory processing and attention mechanisms at the thalamic level and suggest that positive modulation of mGlu1 receptors might be a useful mechanism for enhancing cognitive and attentional processes.

Managing chlamydia infections in young men: results from an audit of a public men's clinic in New York City

Research on management of Chlamydia trachomatis (CT) among men has largely been neglected. Findings from an audit of 284 CT-infected men from 2004 to 2005 attending a young men's clinic primarily serving Latino men in New York City, NY, USA, are presented. Ninety-nine percent received treatment, with 81% treated within 14 days of a positive test. Three percent reported no partner in the last three months, 17% were referred by a CT-positive partner and 24% were missing partner information. Among the rest, 18% received expedited partner therapy, 4% directly observed therapy, 12% partner referral and 65% did not receive documented partner management. Of the 34% who had a post-treatment visit at least three months after their index visit, only 36% received a test for re-infection. Among primarily Latino men in an urban clinic in New York City, a high proportion of CT cases were treated in a timely manner. However, documentation of partner management was often lacking and few CT cases received tests for re-infection.

Smoking in pregnant women screened for an opioid agonist medication study compared to related pregnant and non-pregnant patient samples

BACKGROUND

Little is known about the prevalence and severity of smoking in pregnant opioid dependent patients.

OBJECTIVES

To first characterize the prevalence and severity of smoking in pregnant patients screened for a randomized controlled trial, Maternal Opioid Treatment: Human Experimental Research (MOTHER), comparing two agonist medications; and second, to compare the MOTHER screening sample to published samples of other pregnant and/or patients with substances use disorders.

METHODS

Pregnant women (N = 108) screened for entry into an agonist medication comparison study were retrospectively compared on smoking variables to samples of pregnant methadone-maintained patients (N = 50), pregnant opioid or cocaine dependent patients (N = 240), non-pregnant methadone-maintained women (N = 75), and pregnant non-drug-addicted patients (N = 1,516).

RESULTS

Of screened patients, 88% (n = 95) smoked for a mean of 140 months (SD = 79.0) starting at a mean age of 14 (SD = 3.5). This rate was similar to substance use disordered patients and significantly higher compared to general pregnant patients (88% vs. 22%, p < .001).

CONCLUSION AND SCIENTIFIC SIGNIFICANCE

Aggressive efforts are needed to reduce/eliminate smoking in substance-abusing pregnant women.

Prevalence, distribution and correlates of endocervical human papillomavirus types in Brazilian women

We determined the prevalence, distribution and correlates of human papillomavirus (HPV) types in 386 mixed-income, sexually active women in São Paulo, Brazil. Endocervical samples were tested for HPV DNA with L1 primers MY09 and MY11; negative and indeterminate samples were retested using GP 5+/6+ consensus primers. HPV was detected in 35% of all women; high-risk/probable high-risk types in 20%; low-risk types in 7%; and an indeterminate type in 10%. Twenty-five HPV types were found overall: 17 (probable) high-risk types and eight low-risk types. Approximately one-third (29%) of women with HPV infection were positive for type 16 or 18 and 36% were positive for types 6, 11, 16 or 18. The presence of (probable) high-risk HPV was associated with younger age, more lifetime sex partners and abnormal vaginal flora. Additional studies mapping the distribution of HPV types worldwide are necessary to prepare for vaccination programmes and direct future vaccine development.

Addiction severity index composite scores as predictors for sexual-risk behaviors and drug-use behaviors in drug-using pregnant patients

BACKGROUND

HIV sexual-risk and drug-use behavior predictors have been studied in non-pregnant but not pregnant drug-dependent populations.

OBJECTIVE

Examine the ability of the ASI composite scores to predict HIV sexual- and drug-risk scores as well as the individual items of a modified version of the Risk Assessment Battery in drug-using pregnant women.

METHODS

Pregnant women (N = 76) completing pretreatment ASI and HIV-risk questionnaires.

RESULTS

The Legal composite score was the sole significant predictor of the sexual-risk score, with a 1 SD increase in the Legal composite score resulting in a 24% increase in sexual-risk, p < .001. The Medical, Drug, and Legal composite scores were each significant predictors of the drug-risk score, with a 1 SD increase resulting in a 31% decrease, and 121% and 73% increases, respectively, in drug-risk, all ps < .05.

CONCLUSIONS AND SCIENTIFIC SIGNIFICANCE

Drug-using pregnant women and their fetuses are vulnerable to the consequences of both sexual-risk behaviors and drug-use. The ASI may help screen such patients for HIV sexual-risk and drug-use behaviors as a first step in tailoring treatment to address these issues.

Differing prevalence and diversity of bacterial species in fetal membranes from very preterm and term labor

BACKGROUND

Intrauterine infection may play a role in preterm delivery due to spontaneous preterm labor (PTL) and preterm prolonged rupture of membranes (PPROM). Because bacteria previously associated with preterm delivery are often difficult to culture, a molecular biology approach was used to identify bacterial DNA in placenta and fetal membranes.

METHODOLOGY/PRINCIPAL FINDINGS

We used broad-range 16S rDNA PCR and species-specific, real-time assays to amplify bacterial DNA from fetal membranes and placenta. 74 women were recruited to the following groups: PPROM <32 weeks (n = 26; 11 caesarean); PTL with intact membranes <32 weeks (n = 19; all vaginal birth); indicated preterm delivery <32 weeks (n = 8; all caesarean); term (n = 21; 11 caesarean). 50% (5/10) of term vaginal deliveries were positive for bacterial DNA. However, little spread was observed through tissues and species diversity was restricted. Minimal bacteria were detected in term elective section or indicated preterm deliveries. Bacterial prevalence was significantly increased in samples from PTL with intact membranes [89% (17/19) versus 50% (5/10) in term vaginal delivery p = 0.03] and PPROM (CS) [55% (6/11) versus 0% (0/11) in term elective CS, p = 0.01]. In addition, bacterial spread and diversity was greater in the preterm groups with 68% (13/19) PTL group having 3 or more positive samples and over 60% (12/19) showing two or more bacterial species (versus 20% (2/10) in term vaginal deliveries). Blood monocytes from women with PTL with intact membranes and PPROM who were 16S bacterial positive showed greater level of immune paresis (p = 0.03). A positive PCR result was associated with histological chorioamnionitis in preterm deliveries.

CONCLUSION/SIGNIFICANCE

Bacteria are found in both preterm and term fetal membranes. A greater spread and diversity of bacterial species were found in tissues of women who had very preterm births. It is unclear to what extent the greater bacterial prevalence observed in all vaginal delivery groups reflects bacterial contamination or colonization of membranes during labor. Bacteria positive preterm tissues are associated with histological chorioamnionitis and a pronounced maternal immune paresis.

Correlations of maternal buprenorphine dose, buprenorphine, and metabolite concentrations in meconium with neonatal outcomes

For the first time, relationships among maternal buprenorphine dose, meconium buprenorphine and metabolite concentrations, and neonatal outcomes are reported. Free and total buprenorphine and norbuprenorphine, nicotine, opiates, cocaine, benzodiazepines, and metabolites were quantified in meconium from 10 infants born to women who had received buprenorphine during pregnancy. Neither cumulative nor total third-trimester maternal buprenorphine dose predicted meconium concentrations or neonatal outcomes. Total buprenorphine meconium concentrations and buprenorphine/norbuprenorphine ratios were significantly related to neonatal abstinence syndrome (NAS) scores >4. As free buprenorphine concentration and percentage free buprenorphine increased, head circumference decreased. Thrice-weekly urine tests for opiates, cocaine, and benzodiazepines and self-reported smoking data from the mother were compared with data from analysis of the meconium to estimate in utero exposure. Time of last drug use and frequency of use during the third trimester were important factors associated with drug-positive meconium specimens. The results suggest that buprenorphine and metabolite concentrations in the meconium may predict the onset and frequency of NAS.

The role of beta2 integrins and lipopolysaccharide-binding protein in the phagocytosis of dead Neisseria meningitidis

Phagocytosis of microbial pathogens is essential for the host immune response to infection. Our previous work has shown that lipooligosaccharide (LOS) expression on the surface of Neisseria meningitidis (Nm) is essential for phagocytosis, but the receptor involved remained unclear. In this study, we show that human CR3 (CD11b/CD18) and CR4 (CD11c/CD18) are phagocytic receptors for Nm as illustrated by the capacity of CR3- and CR4-transfected Chinese hamster ovary (CHO) cells to facilitate Nm uptake. A CR3-signalling mutant failed to internalize Nm, showing that the ability of CR3 to signal is essential for phagocytosis. Internalization of Nm by CR3-transfected CHO cells could be inhibited by the presence of CR3-specific antibodies. Furthermore, dendritic cells from leukocyte adhesion deficiency-1 patients, who have diminished expression of beta2 integrins, showed markedly reduced phagocytosis of Nm. The CR3-mediated phagocytosis required the presence of lipopolysaccharide-binding protein (LBP). Furthermore, the expression of LOS by Nm was essential for LBP binding and phagocytosis via CR3. These results reveal a critical role of CR3 and LBP in the phagocytosis of Nm and provide important insights into the initial interaction meningococci have with the immune system.

The differential response of human dendritic cells to live and killed Neisseria meningitidis

There is currently no effective vaccine for Neisseria meningitidis (Nm) serogroup B. Generation of optimal immune responses to meningococci could be achieved by targeting meningococcal antigens to human dendritic cells (DCs). Recent studies have shown that diverse DC responses and subsequent generation of protective immunity can be observed if the microbes are viable or killed. This is important because the host is likely to be exposed to both live and killed bacteria during natural infection. There are currently few data on comparative DC responses to live and killed meningococci. We show here that exposure of human DC to live meningococci does not result in a typical maturation response, as determined by the failure to upregulate CD40, CD86, HLA-DR and HLA-Class I. Despite this, live meningococci were potent inducers of IL-12 and IL-10, although the ratios of these cytokines differed from those to killed organisms. Our data also suggest that enhanced phagocytosis of killed organisms compared with live may be responsible for the differential cytokine responses, involving an autocrine IL-10-dependent mechanism. The consequences of these findings upon the effectiveness of antigen presentation and T-cell responses are currently under investigation.

Home-based versus clinic-based self-sampling and testing for sexually transmitted infections in Gugulethu, South Africa: randomised controlled trial

OBJECTIVES

To test whether more women are screened for sexually transmitted infections when offered home-based versus clinic-based testing and to evaluate the feasibility and acceptability of self-sampling and self-testing in home and clinic settings in a resource-poor community.

METHODS

Women aged 14-25 were randomised to receive a home kit with a pre-paid addressed envelope for mailing specimens or a clinic appointment, in Gugulethu, South Africa. Self-collected vaginal swabs were tested for gonorrhoea, chlamydia and trichomoniasis using PCR and self-tested for trichomoniasis using a rapid dipstick test. All women were interviewed at enrollment on sociodemographic and sexual history, and at the 6-week follow-up on feasibility and acceptability.

RESULTS

626 women were enrolled in the study, with 313 in each group; 569 (91%) completed their 6-week follow-up visit. Forty-seven per cent of the women in the home group successfully mailed their packages, and 13% reported performing the rapid test and/or mailing the kit (partial responders), versus 42% of women in the clinic group who kept their appointment. Excluding partial responders, women in the home group were 1.3 (95% CI 1.1 to 1.5) times as likely to respond to the initiative as women in the clinic group. Among the 44% who were tested, 22% tested positive for chlamydia, 10% for trichomoniasis, and 8% for gonorrhoea.

CONCLUSIONS

Self-sampling and self-testing are feasible and acceptable options in low-income communities such as Gugulethu. As rapid diagnostic tests become available and laboratory infrastructure improves, these methodologies should be integrated into services, especially services aimed at young women.

Growth factor signalling in endocrine and anti-growth factor resistant breast cancer

Growth factors provide powerful mitogenic and survival signals to breast cancer cells and it is therefore not surprising that they are able to subvert inhibitory responses to anti-hormonal drugs. In this review we discuss several mechanisms by which this may be achieved and expand our observations to encompass recently emerging anti-growth factor treatments. The information presented is underpinned by inhibitor studies that show the targeting of such mechanisms in advance of anti-hormone or anti-growth factor resistance development is able to substantially delay this event, thus pointing the way forward to intelligent combination therapies relevant to the future management of breast cancer.

A major role for intestinal epithelial nucleotide oligomerization domain 1 (NOD1) in eliciting host bactericidal immune responses to Campylobacter jejuni

Campylobacter jejuni is the foremost cause of bacterial-induced diarrhoeal disease worldwide. Although it is well established that C. jejuni infection of intestinal epithelia triggers host innate immune responses, the mechanism(s) involved remain poorly defined. Innate immunity can be initiated by families of structurally related pattern-recognition receptors (PRRs) that recognize specific microbial signature motifs. Here, we demonstrated maximal induction of epithelial innate responses during infection with live C. jejuni cells. In contrast when intestinal epithelial cells (IECs) were exposed to paraformaldehyde-fixed bacteria, host responses were minimal and a marked reduction in the number of intracellular bacteria was noted in parallel. These findings suggested a role for intracellular host-C. jejuni interactions in eliciting early innate immunity. We therefore investigated the potential involvement of a family of intracellular, cytoplasmic PRRs, the nucleotide-binding oligomerization domain (NOD) proteins in C. jejuni recognition. We identified NOD1, but not NOD2, as a major PRR for C. jejuni in IEC. We also found that targeting intestinal epithelial NOD1 with small interfering RNA resulted in an increase in number of intracellular C. jejuni, thus highlighting a critical role for NOD1-mediated antimicrobial defence mechanism(s) in combating this infection at the gastrointestinal mucosal surface.

Inhibition of insulin receptor isoform-A signalling restores sensitivity to gefitinib in previously de novo resistant colon cancer cells

Resistance to antiepidermal growth factor (EGFR) strategies is an emerging clinical problem. Using human colorectal cancer (CRC) cells, we evaluated the involvement of the insulin receptor isoform-A (InsR-A) in de novo resistance to gefitinib, an EGFR tyrosine kinase inhibitor. Challenging the EGFR positive LoVo cells with gefitinib (1 microM) resulted in a small ( approximately 18%) inhibition of cell growth and although a modest reduction in phospho (p)EGFR Tyr845 was seen, pEGFR at residues -Tyr1068 and -Tyr1173 were unchanged. LoVo cells produced unprocessed pro-IGF-1R protein, substantial levels of IGF-II mRNA and mature InsR protein, consisting mainly of the InsR-A isoform. Insulin and IGF-II promoted cell growth and pEGFR Tyr845, Tyr1068 and Tyr1173 activity and conversely, the insulin-like growth factor-1 receptor (IGF-1R)/InsR inhibitor ABDP (1 muM) inhibited growth and reduced pEGFR activity at all three tyrosine residues. pInsR and pAkt levels were increased after gefitinib treatment. Blocking of pInsR with ABDP enabled gefitinib to markedly reduce pEGFR Tyr845, Tyr1068 and Tyr1173. Short-term gefitinib/ABDP dual treatment was more effective than either agent alone and chronic exposure to this combination resulted in total cell loss after 9 weeks, preventing acquisition of resistance to ABDP. LoVo cells with acquired resistance to ABDP were acutely sensitive to gefitinib. We concluded that InsR-A reduces sensitivity to gefitinib in LoVo CRC cells, thus its co-targeting alongside EGFR can improve the anti-tumour effect of gefitinib.