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Visual system function depends upon the elaboration of precise connections between retinal ganglion cell (RGC) axons and their central targets in the brain. Though some progress has been made in defining the molecules that regulate RGC connectivity required for the assembly and function of image-forming circuitry, surprisingly little is known about factors required for intrinsically photosensitive RGCs (ipRGCs) to target a principal component of the non-image-forming circuitry: the suprachiasmatic nucleus (SCN). Furthermore, the molecules required for forming circuits critical for circadian behaviors within the SCN are not known. We observe here that the adhesion molecule teneurin-3 (Tenm3) is highly expressed in vasoactive intestinal peptide (VIP) neurons located in the core region of the SCN. Since Tenm3 is required for other aspects of mammalian visual system development, we investigate roles for Tenm3 in regulating ipRGC-SCN connectivity and function. Our results show that Tenm3 negatively regulates association between VIP and arginine vasopressin (AVP) neurons within the SCN and is essential for M1 ipRGC axon innervation to the SCN. Specifically, in Tenm3-/- mice, we find a reduction in ventro-medial innervation to the SCN. Despite this reduction, Tenm3-/- mice have higher sensitivity to light and faster re-entrainment to phase advances, probably due to the increased association between VIP and AVP neurons. These data show that Tenm3 plays key roles in elaborating non-image-forming visual system circuitry and that it influences murine responses to phase-advancing light stimuli., Competing Interests: The authors have declared that no competing interests exist., (Copyright: This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.)

Viruses are increasingly recognised as important components of the human microbiome, fulfilling numerous ecological roles including bacterial predation, immune stimulation, genetic diversification, horizontal gene transfer, microbial interactions, and augmentation of metabolic functions. However, our current view of the human gut virome is tainted by previous sequencing requirements that necessitated the amplification of starting nucleic acids. In this study, we performed an original longitudinal analysis of 40 healthy control, 19 Crohn's disease, and 20 ulcerative colitis viromes over three time points without an amplification bias, which revealed and highlighted the interpersonal individuality of the human gut virome. In contrast to a 16 S rRNA gene analysis of matched samples, we show that α- and β-diversity metrics of unamplified viromes are not as efficient at discerning controls from patients with inflammatory bowel disease. Additionally, we explored the intrinsic properties of unamplified gut viromes and show there is considerable interpersonal variability in viral taxa, infrequent longitudinal persistence of intrapersonal viruses, and vast fluctuations in the abundance of temporal viruses. Together, these properties of unamplified faecal viromes confound the ability to discern disease associations but significantly advance toward an unbiased and accurate representation of the human gut virome., (© 2023. The Author(s).)

Exposure to irregular lighting schedules leads to deficits in affective behaviors. The retino-recipient perihabenular nucleus (PHb) of the dorsal thalamus has been shown to mediate these effects in mice. However, the mechanisms of how light information is processed within the PHb remains unknown. Here, we show that the PHb contains a distinct cluster of GABAergic neurons that receive direct retinal input. These neurons are part of a larger inhibitory network composed of the thalamic reticular nucleus and zona incerta, known to modulate thalamocortical communication. In addition, PHb GABA neurons locally modulate excitatory-relay neurons, which project to limbic centers. Chronic exposure to irregular light-dark cycles alters photo-responsiveness and synaptic output of PHb GABA neurons, disrupting daily oscillations of genes associated with inhibitory and excitatory PHb signaling. Consequently, selective and chronic PHb GABA manipulation results in mood alterations that mimic those caused by irregular light exposure. Together, light-mediated disruption of PHb inhibitory networks underlies mood deficits.

We compiled a human metagenome assembled plasmid (MAP) database and interrogated differences across multiple studies that were originally designed to investigate the composition of the human microbiome across various lifestyles, life stages and events. This was performed as plasmids enable bacteria to rapidly expand their functional capacity through mobilisation, yet their contribution to human health and disease is poorly understood. We observed that inter-sample β-diversity differences of plasmid content (plasmidome) could distinguish cohorts across a multitude of conditions. We also show that reduced intra-sample plasmidome α-diversity is consistent amongst patients with inflammatory bowel disease (IBD) and Clostridioides difficile infections. We also show that faecal microbiota transplants can restore plasmidome diversity. Overall plasmidome diversity, specific plasmids, and plasmid-encoded functions can all potentially act as biomarkers of IBD or its severity. The human plasmidome is an overlooked facet of the microbiome and should be integrated into investigations regarding the role of the microbiome in promoting health or disease. Including MAP databases in analyses will enable a greater understanding of the roles of plasmid-encoded functions within the gut microbiome and will inform future human metagenome analyses., (© 2022. The Author(s).)

Human hydatid disease is still endemic in pastoral and rangeland areas, with temperate climate, mainly in the southern shore of the Mediterranean, particularly in the Maghreb countries. Renal localization is rare although it is the most frequent site of the urinary tract. Its clinical evolution remains silent for long time, and the diagnosis is often elusive for years. Renal hydatid cysts may pose a problem of differential diagnosis. Our case concerns a renal hydatidosis misdiagnosed as a xanthogranulomatous pyelonephritis, treated by total nephrectomy., (Published by Oxford University Press and JSCR Publishing Ltd. All rights reserved. © The Author(s) 2021.)

Background: The gut phageome comprises a complex phage community of thousands of individual strains, with a few highly abundant bacteriophages. CrAss-like phages, which infect bacteria of the order Bacteroidales, are the most abundant bacteriophage family in the human gut and make an important contribution to an individual's core virome. Based on metagenomic data, crAss-like phages form a family, with four sub-families and ten candidate genera. To date, only three representatives isolated in pure culture have been reported: ΦcrAss001 and two closely related phages DAC15 and DAC17; all are members of the less abundant candidate genus VI. The persistence at high levels of both crAss-like phage and their Bacteroidales hosts in the human gut has not been explained mechanistically, and this phage-host relationship can only be properly studied with isolated phage-host pairs from as many genera as possible., Results: Faeces from a healthy donor with high levels of crAss-like phage was used to initiate a faecal fermentation in a chemostat, with selected antibiotics chosen to inhibit rapidly growing bacteria and selectively enrich for Gram-negative Bacteroidales. This had the objective of promoting the simultaneous expansion of crAss-like phages on their native hosts. The levels of seven different crAss-like phages expanded during the fermentation, indicating that their hosts were also present in the fermenter. The enriched supernatant was then tested against individual Bacteroidales strains isolated from the same faecal sample. This resulted in the isolation of a previously uncharacterised crAss-like phage of candidate genus IV of the proposed Alphacrassvirinae sub-family, ΦcrAss002, that infects the gut commensal Bacteroides xylanisolvens. ΦcrAss002 does not form plaques or spots on lawns of sensitive cells, nor does it lyse liquid cultures, even at high titres. In keeping with the co-abundance of phage and host in the human gut, ΦcrAss002 and Bacteroides xylanisolvens can also co-exist at high levels when co-cultured in laboratory media., Conclusions: We report the isolation and characterisation of ΦcrAss002, the first representative of the proposed Alphacrassvirinae sub-family of crAss-like phages. ΦcrAss002 cannot form plaques or spots on bacterial lawns but can co-exist with its host, Bacteroides xylanisolvens, at very high levels in liquid culture without impacting on bacterial numbers. Video abstract.

Background: Pregnancy complications in combination with postpartum weight retention lead to significant risks of cardiometabolic disease and obesity. The majority of traditional face-to-face interventions have not been effective in postpartum women. Mobile technology enables the active engagement of postpartum women to promote lifestyle changes to prevent chronic diseases., Objective: We sought to employ an interactive, user-centered, and participatory method of development, evaluation, and iteration to design and optimize the mobile health (mHealth) Fit After Baby program., Methods: For the initial development, a multidisciplinary team integrated evidence-based approaches for health behavior, diet and physical activity, and user-centered design and engagement. We implemented an iterative feedback and design process via 3 month-long beta pilots in which postpartum women with cardiometabolic risk factors participated in the program and provided weekly and ongoing feedback. We also conducted two group interviews using a structured interview guide to gather additional feedback. Qualitative data were recorded, transcribed, and analyzed using established qualitative methods. Modifications based on feedback were integrated into successive versions of the app., Results: We conducted three pilot testing rounds with a total of 26 women. Feedback from each pilot cohort informed changes to the functionality and content of the app, and then a subsequent pilot group participated in the program. We optimized the program in response to feedback through three iterations leading to a final version., Conclusions: This study demonstrates the feasibility of using an interactive, user-centered, participatory method of rapid, iterative design and evaluation to develop and optimize a mHealth intervention program for postpartum women., Trial Registration: ClinicalTrials.gov NCT02384226; https://www.clinicaltrials.gov/ct2/show/NCT02384226., (©Jacinda M Nicklas, Jenn A Leiferman, Steven Lockhart, Kristen M Daly, Sheana S Bull, Linda A Barbour. Originally published in JMIR Formative Research (http://formative.jmir.org), 09.04.2020.)

The terrestrial chapter of the Circumpolar Biodiversity Monitoring Programme (CBMP) has the potential to bring international multi-taxon, long-term monitoring together, but detailed fundamental species information for Arctic arthropods lags far behind that for vertebrates and plants. In this paper, we demonstrate this major challenge to the CBMP by focussing on spiders (Order: Araneae) as an example group. We collate available circumpolar data on the distribution of spiders and highlight the current monitoring opportunities and identify the key knowledge gaps to address before monitoring can become efficient. We found spider data to be more complete than data for other taxa, but still variable in quality and availability between Arctic regions, highlighting the need for greater international co-operation for baseline studies and data sharing. There is also a dearth of long-term datasets for spiders and other arthropod groups from which to assess status and trends of biodiversity. Therefore, baseline studies should be conducted at all monitoring stations and we make recommendations for the development of the CBMP in relation to terrestrial arthropods more generally.

The human gut virome is thought to significantly impact the microbiome and human health. However, most virome analyses have been performed on a limited fraction of known viruses. Using whole-virome analysis on a published keystone inflammatory bowel disease (IBD) cohort and an in-house ulcerative colitis dataset, we shed light on the composition of the human gut virome in IBD beyond this identifiable minority. We observe IBD-specific changes to the virome and increased numbers of temperate phage sequences in individuals with Crohn's disease. Unlike prior database-dependent methods, no changes in viral richness were observed. Among IBD subjects, the changes in virome composition reflected alterations in bacterial composition. Furthermore, incorporating both bacteriome and virome composition offered greater classification power between health and disease. This approach to analyzing whole virome across cohorts highlights significant IBD signals, which may be crucial for developing future biomarkers and therapeutics., (Copyright © 2019 Elsevier Inc. All rights reserved.)

The human gut contains a vast array of viruses, mostly bacteriophages. The majority remain uncharacterized, and their roles in shaping the gut microbiome and in impacting on human health remain poorly understood. We performed longitudinal metagenomic analysis of fecal viruses in healthy adults that reveal high temporal stability, individual specificity, and correlation with the bacterial microbiome. Using a database-independent approach that uses most of the sequencing data, we uncovered the existence of a stable, numerically predominant individual-specific persistent personal virome. Clustering of viral genomes and de novo taxonomic annotation identified several groups of crAss-like and Microviridae bacteriophages as the most stable colonizers of the human gut. CRISPR-based host prediction highlighted connections between these stable viral communities and highly predominant gut bacterial taxa such as Bacteroides, Prevotella, and Faecalibacterium. This study provides insights into the structure of the human gut virome and serves as an important baseline for hypothesis-driven research., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Urethral foreign bodies are rare in daily practice, especially in adolescents with no evident history of mental illness. The presentation is usually delayed and a wide variety of objects may be implicated. Treatment by minimally invasive procedures (endoscopy), if possible, is preferred to minimize bladder and urethral injuries and psychiatric evaluation is mandatory to detect an underlying mental disorder. Despite the available literature on self-inserted urethral foreign bodies; the case we report here of urethral self-insertion of a sewing needle in a 14 year-old boy for autoerotic stimulation is very rare.

Extracorporeal shock wave lithotripsy-related pain is the largest limiting factor in this technique. Our study aimed to compare the effectiveness of different types of analgesics for pain management used during ESWL sessions. We conducted a prospective study of 300 patients with urinary lithiasis justifying ESWL treatment. The patients were randomized to three groups: group I, included 100 patients who received intramuscular injection of 2cc of physiological saline solution (placebo), group II included 100 patients who received intramuscular injection of ketoprofen 100mg while group III included 100 patients who received lidocaine and prilocaine topical cream. Visual Analog Scale (VAS) was used to assess pain 10 minutes after and at the end of the session. Mean VAS score 10 minutes after and at the end of ESWL session was 3.7 and 4.91 respectively. There was no significant difference among the three groups with respect to: epidemiological data (age, sex, BMI, patient's history) and the characteristics of the renal stone (side, size, location, presence or not of double-J ureteral catheter). Eleven patients in the Group I terminated treatment early, with a significant difference compared to the other groups (p=0.003). VAS score 10 minutes after and at the end of ESWL session was statistically higher in Group I compared to Groups II and III (p < 0.001). Moreover, ESWL session was significantly more effective in Groups (II and III) compared to Group I (p<0.001). Pain treatment is necessary during ESWL sessions. Two painkillers molecules were assessed, which showed good pain control as well as an increase in the effectiveness of lithotripsy., Competing Interests: Les auteurs ne déclarent aucun conflit d'intérêts.

Biophysical aspects of in vivo tissue microenvironments include microscale mechanical properties, fibrillar alignment, and architecture or topography of the extracellular matrix (ECM). These aspects act in concert with chemical signals from a myriad of diverse ECM proteins to provide cues that drive cellular responses. Here, we used a bottom-up approach to build fibrillar architecture into 3D amorphous hydrogels using magnetic-field driven assembly of paramagnetic colloidal particles functionalized with three types of human ECM proteins found in vivo. We investigated if cells cultured in matrices comprised of fibrils of the same size and arranged in similar geometries will show similar behavior for each of the ECM proteins tested. We were able to resolve spatial heterogeneities in microscale mechanical properties near aligned fibers that were not observed in bulk tissue mechanics. We then used this platform to examine factors contributing to cell alignment in response to topographical cues in 3D laminin-rich matrices. Multiple human cell lines extended protrusions preferentially in directions parallel or perpendicular to aligned fibers independently of the ECM coating. Focal adhesion proteins, as measured by paxillin localization, were mainly diffuse in the cytoplasm, with few puncta localized at the protrusions. Integrin β1 and fascin regulated protrusion extension but not protrusion alignment. Myosin II inhibition did not reduce observed protrusion length. Instead, cells with reduced myosin II activity generated protrusions in random orientations when cultured in hydrogels with aligned fibers. Similarly, myosin II dependence was observed in vivo, where cells no longer aligned along the abluminal surfaces of blood vessels upon treatment with blebbistatin. These data suggest that myosin II can regulate sensing of topography in 3D engineered matrices for both normal and transformed cells., (Published by Elsevier Ltd.)

The inflammatory response, modulated both by tissue resident macrophages and recruited monocytes from peripheral blood, plays a critical role in human diseases such as cancer and neurodegenerative disorders. Here, we sought a model to interrogate human immune behavior in vivo. We determined that primary human monocytes and macrophages survive in zebrafish for up to two weeks. Flow cytometry revealed that human monocytes cultured at the physiological temperature of the zebrafish survive and differentiate comparable to cohorts cultured at human physiological temperature. Moreover, key genes that encode for proteins that play a role in tissue remodeling were also expressed. Human cells migrated within multiple tissues at speeds comparable to zebrafish macrophages. Analysis of gene expression of in vivo educated human macrophages confirmed expression of activated macrophage phenotypes. Here, human cells adopted phenotypes relevant to cancer progression, suggesting that we can define the real time immune modulation of human tumor cells during the establishment of a metastatic lesion in zebrafish.

Background: Recent studies have demonstrated that the human gut is populated by complex, highly individual and stable communities of viruses, the majority of which are bacteriophages. While disease-specific alterations in the gut phageome have been observed in IBD, AIDS and acute malnutrition, the human gut phageome remains poorly characterised. One important obstacle in metagenomic studies of the human gut phageome is a high level of discrepancy between results obtained by different research groups. This is often due to the use of different protocols for enriching virus-like particles, nucleic acid purification and sequencing. The goal of the present study is to develop a relatively simple, reproducible and cost-efficient protocol for the extraction of viral nucleic acids from human faecal samples, suitable for high-throughput studies. We also analyse the effect of certain potential confounding factors, such as storage conditions, repeated freeze-thaw cycles, and operator bias on the resultant phageome profile. Additionally, spiking of faecal samples with an exogenous phage standard was employed to quantitatively analyse phageomes following metagenomic sequencing. Comparative analysis of phageome profiles to bacteriome profiles was also performed following 16S rRNA amplicon sequencing., Results: Faecal phageome profiles exhibit an overall greater individual specificity when compared to bacteriome profiles. The phageome and bacteriome both exhibited moderate change when stored at + 4 °C or room temperature. Phageome profiles were less impacted by multiple freeze-thaw cycles than bacteriome profiles, but there was a greater chance for operator effect in phageome processing. The successful spiking of faecal samples with exogenous bacteriophage demonstrated large variations in the total viral load between individual samples., Conclusions: The faecal phageome sequencing protocol developed in this study provides a valuable additional view of the human gut microbiota that is complementary to 16S amplicon sequencing and/or metagenomic sequencing of total faecal DNA. The protocol was optimised for several confounding factors that are encountered while processing faecal samples, to reduce discrepancies observed within and between research groups studying the human gut phageome. Rapid storage, limited freeze-thaw cycling and spiking of faecal samples with an exogenous phage standard are recommended for optimum results.

Dystrobrevin-binding protein 1 (Dtnbp1) is one of the earliest identified schizophrenia susceptibility genes. Reduced expression of DTNBP1 is commonly found in brain areas of schizophrenic patients. Dtnbp1-null mutant mice exhibit abnormalities in behaviors and impairments in neuronal activities. However, how diminished DTNBP1 expression contributes to clinical relevant features of schizophrenia remains to be illustrated. Here, using a conditional Dtnbp1 knockout mouse line, we identified an in vivo schizophrenia-relevant function of DTNBP1 in pyramidal neurons of the medial prefrontal cortex (mPFC). We demonstrated that DTNBP1 elimination specifically in pyramidal neurons of the mPFC impaired mouse pre-pulse inhibition (PPI) behavior and reduced perisomatic GABAergic synapses. We further revealed that loss of DTNBP1 in pyramidal neurons diminished activity-dependent secretion of brain-derived neurotrophic factor (BDNF). Finally, we showed that chronic BDNF infusion in the mPFC fully rescued both GABAergic synaptic dysfunction and PPI behavioral deficit induced by DTNBP1 elimination from pyramidal neurons. Our findings highlight brain region- and cell type-specific functions of DTNBP1 in the pathogenesis of schizophrenia, and underscore BDNF restoration as a potential therapeutic strategy for schizophrenia., (© US Government (2016). Published by Oxford University Press on behalf of Journal of Molecular Cell Biology, IBCB, SIBS, CAS. All rights reserved.)

The Lepidoptera of North America Network, or LepNet, is a digitization effort recently launched to mobilize biodiversity data from 3 million specimens of butterflies and moths in United States natural history collections (http://www.lep-net.org/). LepNet was initially conceived as a North American effort but the project seeks collaborations with museums and other organizations worldwide. The overall goal is to transform Lepidoptera specimen data into readily available digital formats to foster global research in taxonomy, ecology and evolutionary biology.

A better understanding of mechanisms governing receptor insertion to the plasma membrane (PM) requires an experimental approach with excellent spatial and temporal resolutions. Here we present a strategy that enables dynamic visualization of insertion events for dopamine D2 receptors into the PM. This approach includes tagging a pH-sensitive GFP, superecliptic pHluorin, to the extracellular domain of the receptor. By imaging pHluorin-tagged receptors under total internal reflection fluorescence microscopy (TIRFM), we were able to directly visualize individual receptor insertion events into the PM in cultured neurons. This novel imaging approach can be applied to both secreted proteins and many membrane proteins with an extracellular domain labeled with superecliptic pHluorin, and will ultimately allow for detailed dissections of the key mechanisms governing secretion of soluble proteins or the insertion of different membrane proteins to the PM., (Copyright © 2015 John Wiley & Sons, Inc.)

Background: Listeria monocytogenes is a food-borne pathogen which is the causative agent of listeriosis and can be divided into three evolutionary lineages I, II and III. While all strains possess the well established virulence factors associated with the Listeria pathogenicity island I (LIPI-1), lineage I strains also possess an additional pathogenicity island designated LIPI-3 which encodes listeriolysin S (LLS), a post-translationally modified cytolytic peptide. Up until now, this pathogenicity island has been identified exclusively in a subset of lineage I isolates of the pathogen Listeria monocytogenes., Results: In total 64 L. innocua strains were screened for the presence of LIPI-3. Here we report the identification of an intact LIPI-3 in 11 isolates of L. innocua and the remnants of the cluster in several others. Significantly, we can reveal that placing the L. innocua lls genes under the control of a constitutive promoter results in a haemolytic phenotype, confirming that the cluster is capable of encoding a functional haemolysin., Conclusions: Although the presence of the LIPI-3 gene cluster is confined to lineage I isolates of L. monocytogenes, a corresponding gene cluster or its remnants have been identified in many L. innocua strains.

Lantibiotics are ribosomally synthesised, post-translationally modified antimicrobial peptides produced by Gram positive bacteria, many which have broad-ranging antimicrobial activities. Lantibiotics have long been the subject of investigation with a view to their application as food preservatives or chemotherapeutic agents for clinical and veterinary medicine, while the associated biosynthetic machinery has been employed for peptide engineering purposes. However, although many lantibiotics are produced by generally regarded as safe or food-grade bacteria, it is increasingly apparent that a number of Gram positive pathogens, including strains of Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pyogenes, Streptococcus pneumoniae, Streptococcus mutans, Streptococcus uberis and Enterococcus faecalis, also produce these compounds. It is proposed that production of these antimicrobials may provide the associated microorganisms with a competitive advantage when colonizing/infecting a host, thereby enhancing the virulence of the producing strain. Here we review the production of lantibiotics by these pathogens and discuss how their production may contribute to their disease-causing potential.

Nisin A is the best known and most extensively characterized lantibiotic. As it is ribosomally synthesized, bioengineering-based strategies can be used to generate variants. We have previously demonstrated that bioengineering of the hinge region of nisin A can result in the generation of variants with enhanced anti-microbial activity against Gram-positive pathogens. Here we created a larger bank of hinge variant producers and screened for producers that exhibit enhanced bioactivity as assessed by agar-based assays against a selection of target strains. Further analysis of 12 'lead' variants reveals that in many cases enhanced bioactivity is not attributable to enhanced specific activity but is instead as a consequence of an enhanced ability to diffuse through complex polymers. In the case of two variants, which contain the residues SVA and NAK, respectively, within the hinge region, we demonstrate that this enhanced trait enables the peptides to dramatically outperform nisin A with respect to controlling Listeria monocytogenes in commercially produced chocolate milk that contains carrageenan as a stabilizer., (© 2012 The Authors. Microbial Biotechnology © 2012 Society for Applied Microbiology and Blackwell Publishing Ltd.)

Nisin is a bacteriocin widely utilized in more than 50 countries as a safe and natural antibacterial food preservative. It is the most extensively studied bacteriocin, having undergone decades of bioengineering with a view to improving function and physicochemical properties. The discovery of novel nisin variants with enhanced activity against clinical and foodborne pathogens has recently been described. We screened a randomized bank of nisin A producers and identified a variant with a serine to glycine change at position 29 (S29G), with enhanced efficacy against S. aureus SA113. Using a site-saturation mutagenesis approach we generated three more derivatives (S29A, S29D and S29E) with enhanced activity against a range of Gram positive drug resistant clinical, veterinary and food pathogens. In addition, a number of the nisin S29 derivatives displayed superior antimicrobial activity to nisin A when assessed against a range of Gram negative food-associated pathogens, including E. coli, Salmonella enterica serovar Typhimurium and Cronobacter sakazakii. This is the first report of derivatives of nisin, or indeed any lantibiotic, with enhanced antimicrobial activity against both Gram positive and Gram negative bacteria.

Lantibiotics are antimicrobial peptides that have been the focus of much attention in recent years with a view to clinical, veterinary, and food applications. Although many lantibiotics are produced by food-grade bacteria or bacteria generally regarded as safe, some lantibiotics are produced by pathogens and, rather than contributing to food safety and/or health, add to the virulence potential of the producing strains. Indeed, genome sequencing has revealed the presence of genes apparently encoding a lantibiotic, designated Bsa (bacteriocin of Staphylococcus aureus), among clinical isolates of S. aureus and those associated with community-acquired methicillin-resistant S. aureus (MRSA) infections in particular. Here, we establish for the first time, through a combination of reverse genetics, mass spectrometry, and mutagenesis, that these genes encode a functional lantibiotic. We also reveal that Bsa is identical to the previously identified bacteriocin staphylococcin Au-26, produced by an S. aureus strain of vaginal origin. Our examination of MRSA isolates that produce the Panton-Valentine leukocidin demonstrates that many community-acquired S. aureus strains, and representatives of ST8 and ST80 in particular, are producers of Bsa. While possession of Bsa immunity genes does not significantly enhance resistance to the related lantibiotic gallidermin, the broad antimicrobial spectrum of Bsa strongly indicates that production of this bacteriocin confers a competitive ecological advantage on community-acquired S. aureus.

Streptolysin S (SLS) is a bacteriocin-like haemolytic and cytotoxic virulence factor that plays a key role in the virulence of Group A Streptococcus (GAS), the causative agent of pharyngitis, impetigo, necrotizing fasciitis and streptococcal toxic shock syndrome. Although it has long been thought that SLS and related peptides are produced by GAS and related streptococci only, there is evidence to suggest that a number of the most notorious Gram-positive pathogenic bacteria, including Listeria monocytogenes, Clostridium botulinum and Staphylococcus aureus, produce related peptides. The distribution of the L. monocytogenes cluster is particularly noteworthy in that it is found exclusively among a subset of lineage I strains; i.e., those responsible for the majority of outbreaks of listeriosis. Expression of these genes results in the production of a haemolytic and cytotoxic factor, designated Listeriolysin S, which contributes to virulence of the pathogen as assessed by murine- and human polymorphonuclear neutrophil-based studies. Thus, in the process of establishing the existence of an extended family of SLS-like modified virulence peptides (MVPs), the genetic basis for the enhanced virulence of a proportion of lineage I L. monocytogenes may have been revealed.

Pathologic specimens acquired by anatomy departments may be of fundamental anatomical and clinical interest. In this report we describe a true aneurysm of the left ventricle and we review the relevant clinical records of the patient. A detailed review of the literature on ventricular aneurysms is presented with emphasis on particular aspects of cardiac anatomy., (Copyright 2001 Wiley-Liss, Inc.)

The use of continuous fetal heart rate (FHR) recordings to monitor fetal well-being during labor is standard clinical practice in developed countries. Little is known about the relationship, if any, that exists between these FHR abnormalities and the fetal cardiac musculature and function. The aim of this study was to investigate umbilical artery serum levels of cardiac troponin I, a sensitive and specific marker of myocardial necrosis, and N-terminal pro-brain natriuretic peptide (pro-BNP), a sensitive marker of left ventricular dysfunction, in relation to FHR abnormalities. Umbilical artery blood samples were taken from 27 cases immediately after delivery of the infant. There was evidence of significant FHR abnormalities in 11 of these cases (group 2) and the FHR recording was normal in 16 cases (group 1). The mean N-terminal pro-BNP level in umbilical artery serum in group 2 was 413 fmol/L (SEM = 85) and in group 1 was 223 fmol/L (SEM = 28)(p = 0.022). There was no significant difference observed in cardiac troponin I levels between the two groups. Umbilical artery serum N-terminal pro-BNP is elevated in association with fetal heart rate abnormality in the late stage of labor. This finding suggests that some degree of cardiac compromise accompanies FHR abnormality.

Objectives: To investigate serum levels of amino-terminal pro-brain natriuretic peptide (Nt pro-BNP) as an index of left-ventricular function in normal pregnancy and pregnancies complicated by hypertension and also to investigate levels in both primigravid and multigravid women., Methods: Women with hypertension in pregnancy (at least two readings of systolic blood pressure > 140 mm Hg and diastolic blood pressure > 90 mm Hg) (n = 24) and normotensive women (n = 42) were included in the study. Serum Nt pro-BNP was measured using an enzyme-linked immunosorbent assay technique., Results: The median serum Nt pro-BNP level in pregnancies complicated by hypertension was 420 fmol/L, which was significantly greater than that measured in samples obtained from normotensive women in pregnancy (340 fmol/L) (p = 0.03). There was a nonsignificant trend toward increased levels in proteinuric as compared to nonproteinuric hypertension in pregnancy. Multigravida had higher Nt pro-BNP levels (n = 26; median Nt pro-BNP = 358 fmol/L) than primigravida (n = 16; median Nt pro-BNP = 278 fmol/L) (p = 0.01) in association with normal pregnancy. Multigravida also demonstrated a dramatic rise in serum Nt pro-BNP levels in association with hypertension in pregnancy (n = 13; median Nt pro-BNP = 572 fmol/L) as compared to normal pregnancy (n = 26; median Nt pro-BNP = 358 fmol/L) (p = 0.009)., Conclusion: Serum Nt pro-BNP is elevated in women with hypertensive disorders of pregnancy, indicating elevated left-ventricular filling pressures. Measured serum levels in both normal and hypertensive pregnancy are higher in multigravida than in primigravida.

We performed a meta-analysis of published trials to determine the predictive value of cardiac troponin I (cTnI) and T (cTnT) levels for adverse events (death and myocardial infarction) in acute coronary syndrome without ST elevation (ACS). The accumulated odds ratio (OR) for adverse events (30 days) in ACS with elevated cTnI (n = 5,759) and cTnT (n = 5,483) was 4.9 (95% confidence interval, CI, 3.9-6.2) and 4.6 (95% CI 3.8-5.5), respectively. Trials that mandated timed serum sampling (6 or more hours after symptom onset) had an improved predictive value for elevated cTnI (n = 2,807, OR 8.8; 95% CI 5.9-13.2) and cTnT (n = 1,990, OR 8.5; 95% CI 5.9-12.5). In conclusion, cTnI and cTnT provide similar information in ACS. The risk of adverse events is 4-fold higher in patients with suspected ACS and elevated serum cTn. For patients with an elevated timed (6-hour) sample the risk is over 8-fold higher., (Copyright 2001 S. Karger AG, Basel)

Three boys from two families were identified as having a syndrome of X-linked mental retardation (XLMR) with microcephaly and short stature, clinically resembling Renpenning syndrome but with normal size of testicles in affected men. When the effort to map the gene for the above condition was initiated, it was realized that the two families were actually related to each other. Over 50 polymorphic markers of known locations along the X chromosome were scored in this family in a study to map the disease gene. Nine affected and four unaffected males were genotyped to produce a maximum LOD score of 4.42 at zero recombination with markers in proximal Xq. The results indicate that the gene responsible for this disorder is located in the cytogenetic Xq12 to Xq21.31 interval of the X chromosome within a section of chromosome of about 17 cM between the AR and DXS1217 loci over some 25 mb. Since the gene for the X-linked mental retardation from the original Saskatchewan family described by Renpenning [Renpenning et al., 1962: Can Med Assoc J 87:954-956; Fox and Gerrard, 1980: Am J Med Genet 7:491-495] was recently mapped to a different nonoverlapping region [Stevenson et al., 1998: Am J Hum Genet 62:1092-1101] this would appear to be a separate disorder.

Although many associations have been found between specific HLA antigens and an increased susceptibility to various diseases, previous attempts to associate class I and II antigens with acute myeloid leukemia (AML) have been inconclusive, probably due in part to the heterogeneity of AML. We subdivided 165 consecutive adults with AML de novo into distinct clinical, morphological, and cytogenetic subsets and then tested for statistically significant associations with specific HLA antigens. Both morphology and cytogenetic pattern identified subsets of patients with important clinical features and different outcomes. Ten statistically significant (P < 0.05) HLA cytogenetic associations were observed: HLA-A11 with t(8;21), A26 with t(15;17), B7 with 11q23 abnormalities, B44 with +8, Cw2 with -20/del(20q), DR3 with t(15;17) and FAB-M3, DR4 with inv(16) and FAB-M4Eo, DQ2 with +8, and DQ6 with +22. HLA-DQ1 had a negative association with -5/del(5q), which was present in 13% of the 165 AML patients overall but in none of the 27 with DQ1. Certain HLA antigens were significantly correlated with more favorable remission rates, remission duration and survival. Possible mechanisms for the association of HLA antigens with particular subtypes of AML include the linkage or co-inheritance of an oncogene, the facilitation of binding of a transforming virus, toxin, or cytokine, or a permissive role involving impaired immune recognition of an emerging neoplasm. Given the heterogeneity of both the HLA system of immune recognition genes and the cytogenetic subtypes of AML, however, larger numbers of patients must be studied to have confidence that biologically important relationships truly exist.

It has been suggested that circulating immune complexes (CIC) favor tumor progression by suppressing the host's immune response to malignant cells via blocking factors to cell-mediated cytotoxicity. We prospectively measured CIC by the C1q binding assay in 100 untreated patients with acute myeloid leukemia (AML) de novo. The median CIC level was 135, the range 0-1000, and the mean +/- standard error (SE) 175 +/- 18 micrograms/ml. Sixty-eight patients, termed abnormal, had C1q binding levels greater than 2SE above the mean of the normal population (61 +/- 15 micrograms/ml). There were no significant differences between the 32 patients with normal CIC and the 68 with abnormally elevated CIC in any pretreatment characteristic: gender, age, white blood cell count (WBC), platelets, leukemia cell mass, LDH, immunoglobulins, or fibrinogen. Abnormal CIC levels did not correlate with FAB morphology, the presence of a clonal chromosomal abnormality (76% of all patients), or with specific cytogenetic subgroups, although nine of 11 patients with acute promyelocytic leukemia and t(15;17) had abnormal CIC. There were no significant differences in complete remission (CR) rates after the first chemotherapy course (45 vs 40% for normal vs abnormal CIC) or after all courses of treatment (55 vs 65%). Survival from diagnosis was not significantly different for the normal and abnormal groups (9.3 vs 5.8 months, p = 0.24), but survival after achieving a CR was markedly longer for those with normal pretreatment CIC (33.8 vs 11.7 months, p = 0.0068). Pretreatment CIC strongly correlated with remission duration for the 59 patients who achieved CR (16.5 months for 17 normal patients vs 6.9 months for 42 abnormal patients, p = 0.0002). This was independent of age, WBC, leukemia cell mass, or FAB morphology. Within the lowest C1q quartile (less than 60 micrograms/ml), 43% of the patients have not relapsed with a minimum follow-up of 18 months compared to only 6-14% for the three higher quartiles. We conclude that host immunity as assessed by CIC levels has little effect on the initial response to therapy but may play a role in maintaining remission in AML.

A sensitive and specific high-performance liquid chromatographic (HPLC) assay was developed for the quantitation of mitoxantrone in plasma using electrochemical detection. Bisantrene was chosen as the internal standard. A reversed-phase, 10-microns muBondapak C18 analytical column (30 cm X 3.9 mm) with an isocratic mobile phase of 28% acetonitrile in 80 mM sodium formate buffer (pH 3.0) was used. The eluent was monitored by both electrochemical detection at an applied potential of +0.75 V vs. Ag/AgCl and visible absorbance at 660 nm. Only electrochemical detection was able to quantitate the internal standard and provided ten times higher sensitivity than visible absorbance for mitoxantrone with a detection limit as low as 0.1 ng/ml. Calibration curves in the range 0.1-1000 ng/ml showed good linearity (r = 0.998) and precision (coefficient of variation less than 10%). This HPLC method utilized a reproducible and inexpensive liquid-liquid extraction procedure. Using methylene chloride, the extraction efficacy of mitoxantrone from plasma was 85.3% with a coefficient of variation less than 2.1%. This new assay was then applied to measure mitoxantrone concentrations in plasma obtained from two leukemic patients receiving 12 mg/m2 mitoxantrone as a 1-h infusion.

There is considerable uncertainty about the value of endomyocardial biopsy (EMB) in the diagnosis and management of patients with suspected primary myocardial dysfunction. To determine the clinical utility of this procedure in patients referred to our centre, we reviewed the clinical records and biopsy findings of the first 21 consecutive patients in whom we performed right ventricular EMB. Patients were divided into four groups according to the clinical indications for EMB: unexplained congestive cardiac failure and a dilated heart (Group 1: 11 patients); unexplained congestive cardiac failure and a non dilated heart (Group 2: three patients); unexplained cardiomegaly in the absence of cardiac failure (Group 3: one patient); suspected hypertrophic cardiomyopathy (HCM) (Group 4: six patients). Histological examination of EMB tissue obtained from all patients in Group 1 as well as the single patient in Group 3 showed non specific features judged to be compatible with a diagnosis of dilated cardiomyopathy. Accordingly, in all patients in Groups 1 and 3, a potentially treatable cause of primary myocardial dysfunction was excluded. Biopsy examination demonstrated the presence of a specific disease process in two of three patients in Group 2 (one patient had amyloidosis, the other endomyocardial fibrosis). In five of the six patients in Group 4, the biopsy findings were either diagnostic or suggestive of HCM. Our results suggest that EMB is a clinically useful tool in patients presenting with features suggestive of a primary myocardial disorder.

Specific chromosomal abnormalities are independent predictors of response to therapy in acute nonlymphocytic leukemia (ANLL) de novo. In a series of 149 patients with ANLL, we sought to determine whether the t(8;21), t(15;17), t(9;11) or other abnormalities of the long arm of chromosome 11, inv(16) or t(16;16), inv(3) or t(3;3), trisomy 8, and abnormalities of chromosome 5 (-5/5q-) or of chromosome 7 (-7/7q-) identify differences in susceptibility to chemotherapy drugs in vivo. The immediate outcome of the first cycle of remission induction chemotherapy was analyzed for patients in each cytogenetic subgroup as an index of the drug susceptibility of the leukemia cells in vivo. Patients with t(8;21), inv(16), t(16;16), or 11q abnormalities had high rates of complete remission after initial therapy (60-100%), whereas patients with -7/7q- or -5/5q- had low initial response rates (0-36%), suggestive of drug resistance in vivo. In general, cytogenetic groups with high initial complete remission rates ("drug sensitive") also had long disease-free survivals; those groups with low initial remission rates ("drug resistant") had short remission durations even if these patients eventually achieved complete remission with further therapy. Patients with acute promyelocytic leukemia (APL), all of whom had the t(15;17), were the exception; despite low initial remission rates, they had long disease-free survivals, possibly due to a more rapid cytotoxic effect of chemotherapy on the clonogenic APL cells than on the more numerous malignant promyelocytes. We conclude that the prognostic importance of specific chromosomal abnormalities in ANLL resides in part in differing susceptibilities to chemotherapy.

Oral D-xylose absorption and urinary excretion were measured before and after 32 courses of intensive chemotherapy in 14 patients with acute leukemia in complete remission. The incidence of severe and life-threatening infectious complications was greatest in those patients in whom the absorption and excretion of D-xylose fell below normal immediately following 4-7 days of chemotherapy. Gram-negative bacilli and staphylococci were the most common organisms to cause bacteremia in these patients.

Twenty-two patients with hairy cell leukemia were treated with low-dose interferon alfa-2b (0.2 X 10(6) U/m2 given three times weekly) for 6-12 months. The overall response rate was 54%, with only 18% complete plus partial responses. The therapy had to be terminated early in five of these patients because their progressive disease led to severe cytopenia. Although the toxic effects with this regimen were minimal, the significantly lower response rate and the poorer quality of the responses prohibit its use as initial therapy in hairy cell leukemia.

Twenty-two patients with relapsed or refractory acute leukemia received 31 treatment courses of mitoxantrone (10 to 12 mg/m2/d) as a one-hour infusion for five days. Seven of the 13 patients who had greater than or equal to 95% reduction in the leukemia cell mass, calculated using the bone marrow examination on day 6, achieved a complete remission (CR). These remissions lasted up to 14 months without additional therapy. There were no CRs among the 18 patients who had less than 95% cytoreduction by day 6. The sequential addition of 5-azacytidine (200 mg/m2/d) for three days in those patients with residual disease on day 6 provided little additional benefit. Nonhematological toxicity from mitoxantrone was mild, although fever and infection were common. A new high-performance liquid chromatography (HPLC) assay was used to describe the clinical pharmacokinetics of mitoxantrone. Neither clinical response nor toxicity was strongly correlated with the peak plasma mitoxantrone concentration on the first day (mean +/- SD, 510 +/- 206 ng/mL), nor the area under the concentration-time curve (484 +/- 229 ng X h/mL), nor the systemic clearance (405 +/- 124 mL/min/m2). Mitoxantrone causes rapid cytoreduction in acute nonlymphocytic leukemia (ANLL), but the optimal dose and schedule remain to be determined.