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In this review, we discuss violacein and prodigiosin, two chromogenic bacterial secondary metabolites that have diverse biological activities. Although both compounds were “discovered” more than seven decades ago, interest into their biological applications has grown in the last two decades, particularly driven by their antimicrobial and anticancer properties. These topics will be discussed in the first half of this review. The latter half delves into the current efforts of groups to produce these two compounds. This includes in both their native bacterial hosts and heterogeneously in other bacterial hosts, including discussing some of the caveats related to the yields reported in the literature, and some of the synthetic biology techniques employed in this pursuit.

Background At the COVID-19 spring 2020 pandemic peak in Spain, prevalence of SARS-CoV-2 infection in a cohort of 578 randomly selected health care workers (HCWs) from Hospital Clínic de Barcelona was 11.2%. Methods A follow-up survey 1 month later (April-May 2020) measured infection by rRT-PCR and IgM, IgA, and IgG to the receptor-binding domain of the spike protein by Luminex. Antibody kinetics, including IgG subclasses, was assessed until month 3. Results At month 1, the prevalence of infection measured by rRT-PCR and serology was 14.9% (84/565) and seroprevalence 14.5% (82/565). We found 25 (5%) new infections in 501 participants without previous evidence of infection. IgM, IgG, and IgA levels declined in 3 months (antibody decay rates 0.15 [95% CI, .11–.19], 0.66 [95% CI, .54–.82], and 0.12 [95% CI, .09–.16], respectively), and 68.33% of HCWs had seroreverted for IgM, 3.08% for IgG, and 24.29% for IgA. The most frequent subclass responses were IgG1 (highest levels) and IgG2, followed by IgG3, and only IgA1 but no IgA2 was detected. Conclusions Continuous and improved surveillance of SARS-CoV-2 infections in HCWs remains critical, particularly in high-risk groups. The observed fast decay of IgA and IgM levels has implications for seroprevalence studies using these isotypes., SARS-CoV-2 prevalence in 578 health care workers increased from 11.2% at the COVID-19 pandemic peak to 14.9% 1 month later. IgM, IgG, and IgA levels declined over 3 months of follow-up with 68.33%, 3.08%, and 24.29% of seroreversions, respectively.

Maternal behaviors benefit the survival of young, contributing directly to the mother’s reproductive fitness. An extreme form of this is seen in matriphagy, when a mother performs the ultimate sacrifice and offers her body as a meal for her young. Whether matriphagy offers only a single energy-rich meal or another possible benefit to the young is unknown. Here, we characterized the toxicity of a bacterial secondary metabolite, namely, violacein, in Caenorhabditis elegans and found it is not only toxic towards adults, but also arrests growth and development of C. elegans larvae. To counteract this, C. elegans resorted to matriphagy, with the mothers holding their eggs within their bodies and hatching the young larvae internally, which eventually led to the mothers’ death. This violacein-induced matriphagy alleviated some of the toxic effects of violacein, allowing a portion of the internally-hatched young to bypass developmental arrest. Using genetic and pharmacological experiments, we found the consumption of oleate, a monounsaturated fatty acid produced by the mother, during matriphagy is partially responsible. As such, our study provides experimental evidence of why such a drastic and peculiar maternal behavior may have arisen in nematode natural habitats.

Diverse groups of ectoparasitic arthropods cause significant morbidity and mortality in most of the approximately 1.49 billion head of cattle worldwide. Hematophagous ectoparasites (ie, blood-feeding flies, myiasis-causing flies, lice, mites, ticks) are the most important in cattle. Intense use of ectoparasiticides to treat infestations can result in ectoparasite populations becoming resistant to this treatment method. Approaches integrating the use of different technologies are required to manage cattle ectoparasites effectively while addressing societal expectations regarding food safety and environmental health. Assessing the status of coparasitism with ectoparasites and endoparasites in cattle across agroecosystems is critical in advancing integrated parasite management.

This study describes Chromobacterium violaceum's use of extracellular membrane vesicles (MVs) to both solubilize and transport violacein to other microorganisms. Violacein is a hydrophobic bisindole with known antibiotic activities against other microorganisms. Characterization of the MVs found they carried more violacein than protein (1.37 ± 0.19-fold), suggesting they may act as a reservoir for this compound. However, MVs are not produced in response to violacein - a ΔvioA isogenic mutant, which is incapable of making violacein, actually produced significantly more MVs (3.2-fold) than the wild-type strain. Although violacein is insoluble in water (Log Poctanol:water = 3.34), 79.5% remained in the aqueous phase when it was present within the C. violaceum MVs, an increase in solubility of 1740-fold. Moreover, tests with a strain of Staphylococcus aureus showed MV-associated violacein is bactericidal, with 3.1 mg/l killing 90% of S. aureus in 6 h. Tests with the ΔvioA MVs found no loss in the S. aureus viability, even when its MVs were added at much higher concentrations, demonstrating violacein is the active component within the wild-type MVs. In conclusion, our study clearly demonstrates C. violaceum produces MVs and uses them as vehicles to solubilize violacein and transport this hydrophobic antibiotic to other microbes.

Background: Surveillance tools to estimate viral transmission dynamics in young populations are essential to guide recommendations for school opening and management during viral epidemics. Ideally, sensitive techniques are required to detect low viral load exposures among asymptomatic children. We aimed to estimate SARS-CoV-2 infection rates in children and adult populations in a school-like environment during the initial COVID-19 pandemic waves using an antibody-based field-deployable and non-invasive approach. Methods: Saliva antibody conversion defined as ≥ 4-fold increase in IgM, IgA, and/or IgG levels to five SARS-CoV-2 antigens including spike and nucleocapsid constructs was evaluated in 1509 children and 396 adults by high-throughput Luminex assays in samples collected weekly in 22 summer schools and 2 pre-schools in 27 venues in Barcelona, Spain, from June 29th to July 31st, 2020. Results: Saliva antibody conversion between two visits over a 5-week period was 3.22% (49/1518) or 2.36% if accounting for potentially cross-reactive antibodies, six times higher than the cumulative infection rate (0.53%) assessed by weekly saliva RT-PCR screening. IgG conversion was higher in adults (2.94%, 11/374) than children (1.31%, 15/1144) (p=0.035), IgG and IgA levels moderately increased with age, and antibodies were higher in females. Most antibody converters increased both IgG and IgA antibodies but some augmented either IgG or IgA, with a faster decay over time for IgA than IgG. Nucleocapsid rather than spike was the main antigen target. Anti-spike antibodies were significantly higher in individuals not reporting symptoms than symptomatic individuals, suggesting a protective role against COVID-19. Conclusion: Saliva antibody profiling including three isotypes and multiplexing antigens is a useful and user-friendlier tool for screening pediatric populations to detect low viral load exposures among children, particularly while they are not vaccinated and vulnerable to highly contagious variants, and to recommend public health policies during pandemics. This work was supported by the Departament de Salut, Generalitat de Catalunya (grant number SLT006/17/00109). L.I. work was supported by PID2019-110810RB-I00 grant from the Spanish Ministry of Science & Innovation. Development of SARS-CoV-2 reagents was partially supported by the National Institute of Allergy and Infectious Diseases Centers of Excellence for Influenza Research and Surveillance (contract number HHSN272201400008C). ISGlobal receives support from the Spanish Ministry of Science and Innovation through the “Centro de Excelencia Severo Ochoa 2019-2023” Program (CEX2018-000806-S), and support from the Generalitat de Catalunya through the CERCA Program

BackgroundTwo doses of mRNA vaccination have shown >94% efficacy at preventing COVID-19 mostly in naive adults, but it is not clear if the second dose is needed to maximize effectiveness in those previously exposed to SARS-CoV-2 and what other factors affect responsiveness.MethodsWe measured IgA, IgG and IgM levels against SARS-CoV-2 spike (S) and nucleocapsid (N) antigens from the wild-type and S from the Alpha, Beta and Gamma variants of concern, after BNT162b2 (Pfizer/BioNTech) or mRNA-1273 (Moderna) vaccination in a cohort of health care workers (N=578). Neutralizing capacity and antibody avidity were evaluated. Data were analyzed in relation to COVID-19 history, comorbidities, vaccine doses, brand and adverse events.FindingsVaccination induced robust IgA and IgG levels against all S antigens. Neutralization capacity and S IgA and IgG levels were higher in mRNA-1273 vaccinees, previously SARS-CoV-2 exposed, particularly if symptomatic, and in those experiencing systemic adverse effects. A second dose in pre-exposed did not increase antibody levels. Smoking and comorbidities were associated with lower neutralization and antibody levels. Among fully vaccinated, 6.3% breakthroughs were detected up to 189 days post-vaccination. Among pre-exposed non-vaccinated, 90% were IgG seropositive more than 300 days post-infection.InterpretationOur data support administering a single-dose in pre-exposed healthy individuals. However, heterogeneity of responses suggests that personalized recommendations may be necessary depending on COVID-19 history and life-style. Higher mRNA-1273 immunogenicity would be beneficial for those expected to respond worse to vaccination. Persistence of antibody levels in pre-exposed unvaccinated indicates maintenance of immunity up to one year.FundingThis work was supported by Institut de Salut Global de Barcelona (ISGlobal) internal funds, in-kind contributions from Hospital Clínic de Barcelona, the Fundació Privada Daniel Bravo Andreu, and European Institute of Innovation and Technology (EIT) Health (grant number 20877), supported by the European Institute of Innovation and Technology, a body of the European Union receiving support from the H2020 Research and Innovation Programme. We acknowledge support from the Spanish Ministry of Science and Innovation and State Research Agency through the “Centro de Excelencia Severo Ochoa 2019-2023” Program (CEX2018-000806-S), and support from the Generalitat de Catalunya through the CERCA Program. L. I. work was supported by PID2019-110810RB-I00 grant from the Spanish Ministry of Science & Innovation. Development of SARS-CoV-2 reagents was partially supported by the National Institute of Allergy and Infectious Diseases Centers of Excellence for Influenza Research and Surveillance (contract number HHSN272201400008C). The funders had no role in study design, data collection and analysis, the decision to publish, or the preparation of the manuscript.

Unraveling the long-term kinetics of antibodies to SARS-CoV-2 and the individual characteristics influencing it, including the impact of pre-existing antibodies to human coronaviruses causing common cold (HCoVs), is essential to understand protective immunity to COVID-19 and devise effective surveillance strategies. IgM, IgA and IgG levels against six SARS-CoV-2 antigens and the nucleocapsid antigen of the four HCoV (229E, NL63, OC43 and HKU1) were quantified by Luminex, and antibody neutralization capacity was assessed by flow cytometry, in a cohort of health care workers followed up to 7 months (N = 578). Seroprevalence increases over time from 13.5% (month 0) and 15.6% (month 1) to 16.4% (month 6). Levels of antibodies, including those with neutralizing capacity, are stable over time, except IgG to nucleocapsid antigen and IgM levels that wane. After the peak response, anti-spike antibody levels increase from ~150 days post-symptom onset in all individuals (73% for IgG), in the absence of any evidence of re-exposure. IgG and IgA to HCoV are significantly higher in asymptomatic than symptomatic seropositive individuals. Thus, pre-existing cross-reactive HCoVs antibodies could have a protective effect against SARS-CoV-2 infection and COVID-19 disease., Long-term characterisation of SARS-CoV-2 antibody kinetics is needed to understand the protective role of the immune response. Here the authors describe antibody levels and neutralisation activity in healthcare workers over seven months and investigate the role of immunity to endemic human coronaviruses.

The transovarial transmission of tick-borne bacterial pathogens is an important mechanism for their maintenance in natural populations and transmission, causing disease in humans and animals. The mechanism for this transmission and the possible role of tick hormones facilitating this process have never been studied. Injections of physiological levels of the tick hormone, 20-hydroxyecdysone (20E), into part-fed (virgin) adult females of the American dog tick, Dermacentor variabilis, attached to the host caused a reduction in density of Rickettsia montanensis in the carcass and an increase in the ovaries compared to buffer-injected controls. This injection initiates yolk protein synthesis and uptake by the eggs but has no effect on blood feeding. Francisella sp. and R. montanensis were the predominant bacteria based on the proportionality in the carcass and ovary. The total bacteria load increased in the carcass and ovaries, and bacteria in the genus Pseudomonas increased in the carcass after the 20E injection. The mechanism of how the Rickettsia species respond to changes in tick hormonal regulation needs further investigation. Multiple possible mechanisms for the proliferation of R. montanensis in the ovaries are proposed.

The agricultural industry is a critical component of the economy in Pakistan and is a source of income for nearly half of the country’s population. However, damage caused by ticks and tick-borne di...

We evaluated the toxicity of surfactants against different predatory bacteria. Tests with Bdellovibrio bacteriovorus HD100 and SDS, an anionic surfactant, showed the predator was very sensitive; 0.02% SDS completely killed the predatory population (7-log loss; < 10 PFU/ml remaining) both when free-swimming or within the bdelloplast, i.e., intraperiplasmic. Similar results were also observed with B. bacteriovorus 109J and Peredibacter starrii. In contrast, none of the prey (E. coli, Klebsiella pneumoniae, Acinetobacter baumannii, or Pseudomonas sp. DSM 50906) viabilities were negatively affected by SDS. Triton X-100, a nonionic surfactant, was slightly less toxic towards B. bacteriovorus HD100 (viability loss of only 4-log), while two cationic surfactants, i.e., benzalkonium chloride (BZC) and cetyltrimethylammonium bromide (CTAB), were toxic towards both the predator and prey. Based on the above findings, we tested the potential use of SDS as a means to control predation. Addition of 0.02% SDS immediately halted predation based upon the prey bioluminescence, which leveled off and remained steady. This was confirmed using the predator viabilities; no predators were found in any of the samples where SDS was added. Consequently, low concentrations of SDS can be used as a simple means to control B. bacteriovorus HD100 activities.

Anaplasmosis is a widespread tick-borne rickettsial disease responsible for fever, weakness, dyspnea, and progressive anemia in small ruminants, including sheep, goats, deer, and antelope. Anaplasma spp., the causative agent of anaplasmosis, are mainly transmitted via infected ticks to susceptible hosts during blood feeding. These pathogens are particularly devastating to sheep and goat herds in Pakistan, resulting in significant economic losses. However, limited information are available on the epidemiology of Anaplasma spp. among small ruminants in some parts of Pakistan. A commercially available competitive enzyme-linked immunosorbent assay (cELISA) was used to investigate the seroprevalence of Anaplasma antibodies in small ruminants from the three tehsils of the Charsadda District in Pakistan. A total of 600 blood samples (300 sheep and 300 goat) were collected from small farms as well as a standard survey from farmers at each location describing specific aspects related to their livestock management practices. A multivariable logistic regression model was used to assess the relationship between Anaplasma sero-positivity and associated risk factors. The overall seroprevalence of Anaplasma antibodies was higher in goats (25%) than in sheep (19%). A significantly higher infection rate in animals was observed in the Charsadda tehsil compared to the two other tehsils (Shabqadar and Tangi). Age, adopted grazing system, and administrative division were also significant factors for infection (P ≤ 0.5) in animals from all three tehsils studied. Anaplasma spp. infection is a serious health problem in small ruminants in Pakistan and this is the first study focused on quantifying seroprevalence in sheep and goats in the Charsadda District. Further studies are needed to enhance the understanding of factors related to the disease, which can help design new methods for anaplasmosis control in livestock.

Panicum mosaic virus (PMV) (genus Panicovirus, family Tombusviridae) and its molecular parasite, Satellite panicum mosaic virus (SPMV), synergistically interact in coinfected proso and pearl millet (Panicum miliaceum L.) plants resulting in a severe symptom phenotype. In this study, we examined synergistic interactions between the isolates of PMV and SPMV by using PMV-NE, PMV85, SPMV-KS, and SPMV-Type as interacting partner viruses in different combinations. Coinfection of proso millet plants by PMV-NE and SPMV-KS elicited severe mosaic, chlorosis, stunting, and eventual plant death compared with moderate mosaic, chlorotic streaks, and stunting by PMV85 and SPMV-Type. In reciprocal combinations, coinfection of proso millet by either isolate of PMV with SPMV-KS but not with SPMV-Type elicited severe disease synergism, suggesting that SPMV-KS was the main contributor for efficient synergistic interaction with PMV isolates. Coinfection of proso millet plants by either isolate of PMV and SPMV-KS or SPMV-Type caused increased accumulation of coat protein (CP) and genomic RNA copies of PMV, compared with infections by individual PMV isolates. Additionally, CP and genomic RNA copies of SPMV-KS accumulated at substantially higher levels, compared with SMPV-Type in coinfected proso millet plants with either isolate of PMV. Hybrid viruses between SPMV-KS and SPMV-Type revealed that SPMV isolates harboring a CP fragment with four differing amino acids at positions 18, 35, 59, and 98 were responsible for differential synergistic interactions with PMV in proso millet plants. Mutation of amino acid residues at these positions in different combinations in SPMV-KS, similar to those as in SPMV-Type or vice-versa, revealed that A35 and R98 in SPMV-KS CP play critical roles in enhanced synergistic interactions with PMV isolates. Taken together, these data suggest that the two distinct amino acids at positions 35 and 98 in the CP of SPMV-KS and SPMV-Type are involved in the differential synergistic interactions with the helper viruses.

The tricarboxylic acid (TCA) cycle is a mitochondrial metabolic hub that coordinates the metabolism of carbohydrates, proteins, and fats into carbon dioxide and ATP. At specific points in the cycle, the diversion, import, or export of TCA metabolites allows for the dynamic regulation of a variety of tissue and/or cell-specific phenotypic processes. Recent studies have identified that a number of TCA metabolites are important in controlling monocyte/macrophage phenotypes and effector functions while specific macrophage activation or polarization states functionally determine the relative utilization of each. This review focuses on the metabolic reprogramming of the TCA cycle in macrophages and how individual metabolites play a variety of context-specific roles in determining physiologic and pathologic macrophage activation and homeostatic functions. We discuss the implications of these findings and address unanswered questions regarding the role of the TCA cycle in guiding macrophage-dependent immune responses.

Zeb1-induced immune checkpoints promote M2 macrophages and protect invading lung cancer cells from inflammatory cells., The PDL1-PD1 immune checkpoint inhibits T cell activation, and its blockade is effective in a subset of patients. Studies are investigating how checkpoints are hijacked by cancer cells and why most patients remain resistant to immunotherapy. Epithelial mesenchymal transition (EMT), which drives tumor cell invasion via the Zeb1 transcription factor, is linked to immunotherapy resistance. In addition, M2-polarized tumor-associated macrophages (TAMs), which inhibit T cell migration and activation, may also cause immunotherapy resistance. How EMT in invading cancer cells is linked to therapy resistance and events driving TAM M2 polarization are therefore important questions. We show that Zeb1 links these two resistance pathways because it is required for PDL1 expression on invading lung cancer cells, and it also induces CD47 on these invading cells, which drives M2 polarization of adjacent TAMs. Resulting reprogramming of the microenvironment around invading cells shields them from the hostile inflammatory environment surrounding tumors.

Unraveling the long-term kinetics of antibodies to SARS-CoV-2 and its determinants, including the impact of pre-existing antibodies to human coronaviruses causing common cold (HCoVs), is essential to understand protective immunity to COVID-19 and devise effective surveillance strategies. IgM, IgA and IgG levels against six SARS-CoV-2 antigens and the nucleocapsid antigen of the four HCoV (229E,NL63, OC43 and HKU1) were quantified by Luminex, and antibody neutralization capacity was assessed by flow cytometry, in a cohort of health care workers followed-up for 6 months (N = 578). Seroprevalence increased over time from 13.5% (month 0) and 15.6% (month 1) to 16.4% (month 6). Levels of antibodies, including those with neutralizing capacity, were stable over time, except IgG to nucleocapsid antigen and IgM levels that waned. After the peak response, anti-spike antibody levels increased from ∼150 days post-symptom onset in all individuals (73% for IgG), in the absence of any evidence of re-exposure. Pre-existing antibodies to alpha-HCoV were lower in individuals who subsequently seroconverted for SARS-CoV-2. IgG and IgA to HCoV were significantly higher in asymptomatic than symptomatic seropositive individuals. Thus, pre-existing cross-reactive HCoVs antibodies could have a protective effect against SARS-CoV-2 infection and COVID-19 disease.

Purpose Necrotizing enterocolitis (NEC) is one of the most distressing gastrointestinal emergencies affecting neonates. Amniotic fluid stem cells (AFSC) improve intestinal injury and survival in experimental NEC but are difficult to administer. In this study, we evaluated whether conditioned medium (CM) derived from human AFSC have protective effects. Methods Three groups of C57BL/6 mice were studied: (i) breast-fed mice as control; (ii) experimental NEC mice receiving PBS; and (iii) experimental NEC mice receiving CM. NEC was induced between post-natal days P5 through P9 via: (A) gavage feeding of hyperosmolar formula four-time a day; (B) 10 minutes hypoxia prior to feeds; and (C) lipopolysaccharide administration on P6 and P7. Intra-peritoneal injections of either PBS or CM were given on P6 and P7. All mice were sacrificed on P9 and terminal ileum were harvested for analyses. Results CM treatment increased survival and reduced intestinal damage, decreased mucosal inflammation (IL-6; TNF-α), neutrophil infiltration (MPO), and apoptosis (CC3), and also restored angiogenesis (VEGF) in the ileum. Additionally, CM treated mice had increased levels of epithelial proliferation (Ki67) and stem cell activity (Olfm4; Lgr5) compared to NEC+PBS mice, showing restored intestinal regeneration and recovery during NEC induction. CM proteomic analysis of CM content identified peptides that regulated immune and stem cell activity. Conclusions CM derived from human AFSC administered in experimental NEC exhibited various benefits including reduced intestinal injury and inflammation, increased enterocyte proliferation, and restored intestinal stem cell activity. This study provides the scientific basis for the use of CM derived from AFSC in neonates with NEC.

BackgroundAt the peak of the COVID-19 pandemic in Spain, cumulative prevalence of SARS-CoV-2 infection in a cohort of 578 randomly selected health care workers (HCW) from Hospital Clínic de Barcelona was 11.2%.MethodsA follow-up survey one month after the baseline (April-May 2020) measured SARS-CoV-2 infection by real time reverse-transcriptase polymerase chain reaction (rRT-PCR) and IgM, IgA, IgG and subclasses to the receptor-binding domain of the SARS-CoV-2 spike protein by Luminex. Prevalence of infection was defined by a positive SARS-CoV-2 rRT-PCR and/or antibody seropositivity.ResultsThe cumulative prevalence of infection at month 1 was 14.9% (84/565) and the seroprevalence 14.5% (82/565) for IgM and/or IgG and/or IgA. We found 25 (5%) new infections in participants without previous evidence of infection at baseline (501) and two participants seroreverted for IgM and/or IgG and/or IgA. Among seropositive participants at baseline, IgM and IgA levels generally declined at month 1 (antibody decay rates of 0.49 (95% CI, 0.40-0.60) and 0.34 (95% CI, 0.26-0.44)), respectively. Eight percent of the participants seroreverted for IgM and 11% for IgA. Subjects reporting COVID-19-like symptoms and laboratory and other technicians had higher risk of infection. The most frequent subclass responses were IgG1 and IgG2, followed by IgG3, with higher levels of IgG1, and only IgA1 but no IgA2 was detected.ConclusionsOur findings highlight the importance of a continuous and improved surveillance of SARS-CoV-2 infections in HCW, particularly in high risk groups. The decay of IgA and IgM levels have implications for seroprevalence studies using these isotypes.

Health care workers (HCW) are a high-risk population to acquire SARS-CoV-2 infection from patients or other fellow HCW. This study aims at estimating the seroprevalence against SARS-CoV-2 in a random sample of HCW from a large hospital in Spain. Of the 578 participants recruited from 28 March to 9 April 2020, 54 (9.3%, 95% CI: 7.1–12.0) were seropositive for IgM and/or IgG and/or IgA against SARS-CoV-2. The cumulative prevalence of SARS-CoV-2 infection (presence of antibodies or past or current positive rRT-PCR) was 11.2% (65/578, 95% CI: 8.8–14.1). Among those with evidence of past or current infection, 40.0% (26/65) had not been previously diagnosed with COVID-19. Here we report a relatively low seroprevalence of antibodies among HCW at the peak of the COVID-19 epidemic in Spain. A large proportion of HCW with past or present infection had not been previously diagnosed with COVID-19, which calls for active periodic rRT-PCR testing in hospital settings., Health care workers (HCW) are a high-risk population for SARS-CoV-2 infection. Here, the authors determine seroprevalence against SARS-CoV-2 in HCWs of a large Spanish reference hospital and find a cumulative prevalence of SARS-CoV-2 infection (presence of antibodies or past or current positive rRT-PCR) of 11%.

Bdellovibrio bacteriovorus 109J is a predatory bacterium which lives by predating on other Gram-negative bacteria to obtain the nutrients it needs for replication and survival. Here, we evaluated the effects two classes of bacterial signaling molecules (acyl homoserine lactones (AHLs) and diffusible signaling factor (DSF)) have on B. bacteriovorus 109J behavior and viability. While AHLs had a non-significant impact on predation rates, DSF considerably delayed predation and bdelloplast lysis. Subsequent experiments showed that 50 μM DSF also reduced the motility of attack-phase B. bacteriovorus 109J cells by 50% (38.2 ± 14.9 vs. 17 ± 8.9 μm/s). Transcriptomic analyses found that DSF caused genome-wide changes in B. bacteriovorus 109J gene expression patterns during both the attack and intraperiplasmic phases, including the significant downregulation of the flagellum assembly genes and numerous serine protease genes. While the former accounts for the reduced speeds observed, the latter was confirmed experimentally with 50 μM DSF completely blocking protease secretion from attack-phase cells. Additional experiments found that 30% of the total cellular ATP was released into the supernatant when B. bacteriovorus 109J was exposed to 200 μM DSF, implying that this QS molecule negatively impacts membrane integrity.

COVID-19 is a global pandemic that started in Wuhan, China. COVID-19 related liver enzyme elevations have been described however the clinical presentation, enzyme kinetics, and associated laboratory abnormalities of these patients have not been well described. Five cases of COVID-19 associated liver enzyme elevations are reported here. We found that COVID-19 related liver enzyme elevations occurred in a hepatocellular pattern and persisted throughout the initial hospitalization in all patients. Abnormalities in lactate dehydrogenase and ferritin levels were seen in all five cases. In conclusion, abnormalities in aminotransferase, lactate dehydrogenase, and ferritin levels are commonly seen in COVID-19 related liver injury. Elevated aminotransferase levels often persist throughout the entire hospitalization. However, the clinical course of COVID-19 related liver injury appears benign.

Mutations that shorten the lipopolysaccharide (LPS) in Escherichia coli were found to significantly increase the number of transformants after electroporation. The loss of the LPS outer core increased the number of transformants with plasmid pAmCyan (3.3 kb) from 5.0 × 105 colony-forming units (CFU)/μg in the wild-type E. coli BW25113 to 3.3 × 107 CFU/μg in a ΔwaaG background, a 66.2-fold increase in efficiency. Truncation of the inner core improved this even further, with the ΔwaaF mutant exhibiting the best transformation efficiencies obtained, i.e., a 454.7-fold increase in the number of colonies over the wild-type strain. Similar results were obtained when a larger plasmid (pDA1; 11.3 kb) was used, with the ΔwaaF mutant once more giving the best transformation rates, i.e., a 73.7-fold increase. Subsequent tests proved that the enhanced transformabilities of these mutants were not due to a better survival or their surface charge properties, nor from preferential binding of these strains to the plasmid. Using N-phenyl-1-naphthylamine (NPN), we confirmed that the outer membranes of these mutant strains were more permeable. We also found that they leaked more ATP (3.4- and 2.0-fold higher for the ΔwaaF and ΔwaaG mutants, respectively, than wild-type E. coli BW25113), suggesting that the inner membrane stability is also reduced, helping to explain how the DNA enters these cells more easily. KEY POINTS: • LPS inner core gene knockouts increase the electrocompetence of E. coli. • No significant difference in survival, surface charge, or DNA binding was evident. • The LPS inner core mutants, however, exhibited higher outer membrane permeability. • Their inner membranes were also leaky, based on supernatant ATP concentrations.

Additional research on soft ticks in the family Argasidae is needed to bridge the knowledge gap relative to hard ticks of the family Ixodidae; especially, the molecular mechanisms of the Ornithodoros biology. Ornithodoros species are vectors of human and animal pathogens that include tick-borne relapsing fever spirochetes and African swine fever virus. Soft tick vector-pathogen interactions involving components of the tick immune response are not understood. Ticks utilize a basic innate immune system consisting of recognition factors and cellular and humoral responses to produce antimicrobial peptides like defensins. In the present study we identified and characterized the first putative defensins of Ornithodoros turicata, an argasid tick found primarily in the southwestern United States and regions of Latin America. Four genes (otdA, otdB, otdC, and otdD) were identified through sequencing and their predicted amino acid sequences contained motifs characteristic of arthropod defensins. A phylogenetic analysis grouped these four genes with arthropod defensins, and computational structural analyses further supported the identification. Since pathogens transmitted by O. turicata colonize both the midgut and salivary glands, expression patterns of the putative defensins were determined in these tissues one week post engorgement and after molting. Defensin genes up-regulated in the tick midgut one week post blood feeding were otdA and otdC, while otdD was up-regulated in the midgut of post-molt ticks. Moreover, otdB and otdD were also up-regulated in the salivary glands of flat post-molt ticks, while otdC was up-regulated within one week post blood-feeding. This work is foundational toward additional studies to determine mechanisms of vector competence and pathogen transmission from O. turicata.

Acetaminophen is one of the most commonly consumed analgesics world wide. Generally perceived as a safe medication, it is the most common cause of acute liver failure in the United States with inadvertent hepatotoxicity in half of all cases. We therefore conducted a survey on the public perceptions of acetaminophen in patients attending the outpatient clinic in Vancouver, Canada. Among 928 patients who were asked, 765 completed the survey questionnaire. The majority of respondents were female (59%), Caucasian (61%), and educated beyond the secondary school level (81%). 23% reported using acetaminophen at least once a week. A significant minority were unaware of the potential liver toxicity of acetaminophen (24%), and knowledge of hepatotoxicity did not vary with education status. In terms of the medicinal composition of acetaminophen products, over half of the respondents (58%) did not know that extra strength preparations of acetaminophen contained the same drug but in a different dose. This knowledge was more prevalent among those with higher level of education (49% in graduate school educated respondents), but was still low overall. The knowledge that alcohol use with acetaminophen was more harmful was low (43%), but improved with level of education (P for trend 0.03). Among respondents who consumed alcohol regularly, 21% were consuming over 1.5 grams of acetaminophen at a time. These patients had similar harm perception to liver as patients who consumed lower doses of acetaminophen. Overall, in a large, well-educated cohort of patients, knowledge about the adverse effects of acetaminophen, the additional risks with alcohol and composition of various retailed products was suboptimal. We speculate that consumer ignorance is a significant reason why acetaminophen is a leading cause of acute liver failure.

The bluestem gall midge (Stenodiplosis wattsii Gagne) is native to the grasslands of North America. It feeds on the developing seeds of warm-season grasses during a portion of its lifecycle, but little is known of the biology and extent of gall midge infestations in native warm-season grasses in the USA. We investigated the infestations of the bluestem gall midge in big bluestem (Andropogon gerardii Vitman), sand bluestem (Andropogon gerardii var paucipilus), little bluestem [Schizachyrium scoparium (Michx.) Nash], and indiangrass [Sorghastrum nutans (L.) Nash] commercial seed production fields during 2001 through 2004. Our objectives were to determine the annual production cycle of the bluestem gall midge, the range of the infestation in Nebraska, and estimate its impact on seed production. In eastern Nebraska, the midge goes through four generations with the fourth entering a larval diapause, overwintering in seeds and emerging in mid-June of the following year. The bluestem gall midge damaged from 31% of the little bluestem seed to 67% of the big bluestem seed, and, on average, reduced the production of viable seed by 54% across the four grass species in eastern Nebraska. Additionally, the warm-season prairie grasses were surveyed in nine other counties in Nebraska and the bluestem gall midge was found in each species surveyed from all nine counties. This study is the first to document the negative effects of the bluestem gall midge on the production of viable seed in sand bluestem and indiangrass.

Background Inflammatory bowel disease (IBD) in patients with primary sclerosing cholangitis (PSC) is characterized by pancolitis with rectal sparing and is associated with an increased risk of colorectal and biliary malignancies. Currently, pharmacologic management of IBD in the setting of PSC is the same as in IBD alone. Aims To assess patterns in medical therapy, and incidence of adverse outcomes in patients with concomitant IBD and PSC. Methods A retrospective review was conducted on all PSC-IBD patients followed between January 2010 and June 2018. The Endoscopic Mayo Score was used to grade IBD severity in PSC-ulcerative colitis (UC). Results 69 patients were identified, 44 (63.8%) were male. The mean ages of IBD and PSC diagnosis were 28.6 (SD 14.9) and 37.0 (SD 18.9) years, respectively. The median length of follow up was 12 (range 2–49) years. 52 (75.4%) patients had UC, and 17 (24.6%) had Crohn’s disease (CD). 28 (87.5%) PSC-UC patients had pancolitis, and 4 (12.5 %) had proctitis. Among those with pancolitis, 8 (28.6%) had relative rectal sparing. 4 (14.3%) patients had more severe inflammation proximally, whereas only 1 (3.6%) had more severe distal inflammation. 23 (82.1%) patients had the same degree of inflammation throughout. 14 (93.3%) PSC-CD patients had colitis/ileocolitis and 1 (6.7%) had ileitis. Among those with PSC-UC, 16 (50.0%), 12 (37.5%), and 4 (12.5%) patients had grade 1, 2, and 3 disease, respectively. 62 (89.9%) PSC-IBD patients were treated with aminosalicylates, and 26 (37.7%) with biologics at some point in their IBD course. 26 (37.7%) were treated with aminosalicylates alone. 4 (5.8%) did not require any IBD therapy. Cholangiocarcinoma, colorectal cancer, and gallbladder cancer developed in 8 (11.6%), 1 (1.4%), and 1 (1.4%) PSC-IBD patients, respectively. 16 (23.2%) patients required partial or total colectomy. Indication for surgery was inflammation or stenosis, dysplasia, and neoplasia in 13 (81.3%), 2 (12.5%), and 1 (6.3%) patients, respectively. Conclusions The majority of this cohort had UC with mild disease activity. Pancolitis was common, with frequent rectal sparing and more severe right-sided inflammation. Despite the predominance of low-grade colitis, a large portion of patients required treatment with biologics. The incidence of adverse outcomes underscores the need for strict adherence to recommended surveillance practices. Low grade endoscopic activity, typical of the quiescent IBD course in PSC-IBD, may mask low grade histologic inflammation, which in turn may contribute to the increased risk of colonic neoplasia. Further studies are needed to determine the best management strategy for IBD in patients with PSC. Funding Agencies None

One of the defining characteristics of a pre-metastatic niche, a fundamental requirement for primary tumor metastasis, is infiltration of immunosuppressive macrophages. How these macrophages acquire their phenotype remains largely unexplored. Here, we demonstrate that tumor-derived exosomes (TDEs) polarize macrophages toward an immunosuppressive phenotype characterized by increased PD-L1 expression through NF-kB-dependent, glycolytic-dominant metabolic reprogramming. TDE signaling through TLR2 and NF-κB leads to increased glucose uptake. TDEs also stimulate elevated NOS2, which inhibits mitochondrial oxidative phosphorylation resulting in increased conversion of pyruvate to lactate. Lactate feeds back on NF-κB, further increasing PD-L1. Analysis of metastasis-negative lymph nodes of non-small-cell lung cancer patients revealed that macrophage PD-L1 positively correlates with levels of GLUT-1 and vesicle release gene YKT6 from primary tumors. Collectively, our study provides a novel mechanism by which macrophages within a pre-metastatic niche acquire their immunosuppressive phenotype and identifies an important link among exosomes, metabolism, and metastasis.

AIMS Evaluate the use of polyethyleneimines (PEIs) as membrane permeabilizers to improve the responses and sensitivity of a bacterial bioreporter strain to viologens. METHODS AND RESULTS The responses from E. coli str. EBS, i.e., E. coli BW25113 carrying plasmid pSDS, when exposed to five different viologens were characterized, as were the toxicities of seven different PEIS, including two linear and five branched species. Based on these results, benzyl viologen led to the greatest responses, and 0·8-kDa branched PEI (BPEI) was the least toxic of the PEIs tested and, therefore, both were selected for the subsequent tests. The bioluminescence and relative responses from E. coli str. EBS exposed to various concentrations of 0·8 kDa BPEI identified 400 mg l-1 as the optimal concentration. Using this concentration, tests were performed with all five of the viologens. CONCLUSIONS The responses from E. coli str. EBS to the viologens were improved, with the maximum relative bioluminescence values increasing between 5·6 and 16·5-fold. The minimum detectable levels for four of the viologens were likewise improved 2- to 4-fold. SIGNIFICANCE AND IMPACT OF STUDY Improving bacterial membrane permeability in a controlled manner using BPEIs can improve biosensing of toxic compounds, as well as be used in biofuel and bioenergy applications where membrane permeability to a solute is important.

We evaluated the bactericidal activity of Bdellovibrio bacteriovorus, strain HD100, within blood sera against bacterial strains commonly associated with bacteremic infections, including E. coli, Klebsiella pneumoniae and Salmonella enterica. Tests show that B. bacteriovorus HD100 is not susceptible to serum complement or its bactericidal activity. After a two hour exposure to human sera, the prey populations decreased 15- to 7,300-fold due to the serum complement activity while, in contrast, the B. bacteriovorus HD100 population showed a loss of only 33%. Dot blot analyses showed that this is not due to the absence of antibodies against this predator. Predation in human serum was inhibited, though, by both the osmolality and serum albumin. The activity of B. bacteriovorus HD100 showed a sharp transition between 200 and 250 mOsm/kg, and was progressively reduced as the osmolality increased. Serum albumin also acted to inhibit predation by binding to and coating the predatory cells. This was confirmed via dot blot analyses and confocal microscopy. The results from both the osmolality and serum albumin tests were incorporated into a numerical model describing bacterial predation of pathogens. In conclusion, both of these factors inhibit predation and, as such, they limit its effectiveness against pathogenic prey located within sera.

The Asian longhorned beetle Anoplophora glabripennis (Motchulsky) is an exotic forest pest that has repeatedly invaded North America and Europe from Asia, and has the potential to kill millions of trees and cause billions of dollars in damage. Traps baited with an attractive mixture of volatile organic compounds (VOCs) from hosts have been of limited success in monitoring invasion sites. We propose that lures might be improved through studying the olfactory system of adult beetles, especially the gene family of odorant receptors (ORs) and the structure of the antennal lobes of the brain. Here, we report identification of 132 ORs in the genome of A. glabripennis (inclusive of one Orco gene and 11 pseudogenes), some of which are orthologous to known pheromone receptors of other cerambycid beetles. We also identified three ORs that are strongly biased toward expression in the female transcriptome, and a single OR strongly biased toward males. Three-dimensional reconstruction of the antennal lobes of adults suggested a male-specific macroglomerulus and several enlarged glomeruli in females. We predict that functional characterization of ORs and glomeruli will lead to identification of key odorants in the life history of A. glabripennis that may aid in monitoring and controlling future invasions.

The genetics and responses to biotic stressors of tetraploid switchgrass (Panicum virgatum L.) lowland cultivar 'Kanlow' and upland cultivar Summer are distinct and can be exploited for trait improvement. In general, there is a paucity of data on the basal differences in transcription across tissue developmental times for switchgrass cultivars. Here, the changes in basal and temporal expression of genes related to leaf functions were evaluated for greenhouse grown 'Kanlow', and 'Summer' plants. Three biological replicates of the 4th leaf pooled from 15 plants per replicate were harvested at regular intervals beginning from leaf emergence through senescence. Increases and decreases in leaf chlorophyll and N content were similar for both cultivars. Likewise, multidimensional scaling (MDS) analysis indicated both cultivar-independent and cultivar-specific gene expression. Cultivar-independent genes and gene-networks included those associated with leaf function, such as growth/senescence, carbon/nitrogen assimilation, photosynthesis, chlorophyll biosynthesis, and chlorophyll degradation. However, many genes encoding nucleotide-binding leucine rich repeat (NB-LRRs) proteins and wall-bound kinases associated with detecting and responding to environmental signals were differentially expressed. Several of these belonged to unique cultivar-specific gene co-expression networks. Analysis of genomic resequencing data provided several examples of NB-LRRs genes that were not expressed and/or apparently absent in the genomes of Summer plants. It is plausible that cultivar (ecotype)-specific genes and gene-networks could be one of the drivers for the documented differences in responses to leaf-borne pathogens between these two cultivars. Incorporating broad resistance to plant pathogens in elite switchgrass germplasm could improve sustainability of biomass production under low-input conditions.

The aim of this study was to obtain real-world, US, observational data on the effect of baseline resistance-associated substitutions (RASs) on achieving sustained virologic response (SVR) in hepatitis C (HCV) patients treated with direct-acting antiviral (DAA) regimens; the need for long-term follow-up in post-SVR patients. It is uncertain if the presence of RASs limits efficacy to DAAs. Once SVR is achieved, society guidelines recommend long-term surveillance for hepatocellular carcinoma in certain patients. Real-world data are limited on these topics. Adult patients treated with DAAs at community hepatitis clinics between January 2015 and April 2017 were included in this study. Baseline resistance testing was performed before treatment. Per guidelines, post-SVR long-term monitoring was required in patients with F3 to F4 fibrosis before treatment or with elevated ALT levels (>19 U/L females; >30 U/L males). A total of 875 chronic, mostly GT1a (60%) HCV patients were treated with an approved DAA regimen. Average baseline AST and ALT were 75 and 67 U/L, respectively, and 47% had F3 to F4 fibrosis at baseline. SVR was achieved in 863 (98.6%) patients despite a high presence of baseline RASs (61%). Long-term monitoring was required post-SVR in 539 patients (62%). In a real-life, US cohort of HCV-infected patients, nearly all patients achieved SVR with available DAA regimens regardless of baseline RASs. Approximately two-thirds of these patients required long-term follow-up, despite viral eradication.

We have demonstrated respiratory chemosensitivity to changes in (H+) and Pco2 of the cerebrospinal fluid (CSF) in the subarachnoid space on the ventrolateral surface of the medulla. Respiratory stimulation was elicited from this region by increased Pco2 and (H+), nicotine, and acetylcholine; and respiratory depression by procaine, NaCN, lobeline, cold CSF, decreased Pco2 and (H+). CSF made acid by high (Cl-) at constant Pco2 moved the entire CO2 response curve to the left and was a more effective stimulus than normal CSF made acid by equilibration at high Pco2, presumably because of rapid diffusion loss of CO2 from the perfusing CSF into the underlying tissue and blood. Steady rapid perfusion of this area with a mock CSF of normal (H+) and Pco2 had no effect on respiration but depressed the respiratory response to inhaled CO2 by 40%. When placed in the fourth ventricle, procaine and high (H+) and Pco2 did not affect respiration, but nicotine and acetylcholine depressed it. This suggests that part of the medullary respiratory response to inhaled CO2 originates in an (H+)-sensitive surface exposed to CSF on the ventrolateral medulla. Submitted on August 8, 1962

BACKGROUND: Acetaminophen (APAP) is an immensely popular analgesic agent that is sold in Canada without prescription. The incidence of APAP toxicity leading to acute liver failure has increased over the past two decades. Recent data from a US cohort study demonstrates that up to 46% of acute liver failure cases are due to APAP. Published data suggest that accidental hepatotoxicity related to therapeutic misuse of APAP is a relatively common occurrence, especially when APAP is combined with alcohol. It is unclear if patients are aware of differences in dosage formats of APAP and increased potential for hepatotoxicity when APAP is combined with alcohol. AIMS: The aim of this study was to assess patient understanding of APAP, dosage formats, combination with alcohol, and potential for toxicity. METHODS: A survey was given to consecutive patients aged ≥ 18 attending a general gastroenterology clinic in Vancouver, BC. Data collection for this study began in September 2018 and is ongoing. Fisher’s exact test was used to compare categorical variables. P-values were calculated as 2-tailed and a value of ≤ 0.05 was interpreted as significant. RESULTS: This preliminary analysis included 95 respondents, some did not answer all questions. The majority of respondents were female (n=52/94, 54.7%). A majority identified as having university-level education (n=63/94, 67.0%) and Caucasian ethnicity (n=69/94, 73.4%). A minority reported using “regular-strength (RS)” APAP (325mg PO) more than one day per week (n=23/94, 24.5%). A similar number of respondents reported used “extra-strength (ES)” APAP (650mg PO) more than one day per week (n=21/93, 22.6%). Respondents more commonly reported using both RS and ES APAP together over a given stretch of time (n=14/92, 15.2%), than RS APAP alone (n=8/92, 8.7%) or ES APAP alone (n=6/92, 6.5%) (p

Epidemiological studies indicate that light-moderate alcohol (ethanol) consumers tend to have reduced risks of cognitive impairment and progression to dementia during aging. Exploring possible mechanisms, we previously found that moderate ethanol preconditioning (MEP, 20-30 mM) of rat brain cultures for several days instigated neuroprotection against β-amyloid peptides. Our biochemical evidence implicated the NMDA receptor (NMDAR) as a potential neuroprotective “sensor”, specifically via synaptic NMDAR signaling. It remains unclear how ethanol modulates the receptor and its downstream targets to engender neuroprotection. Here we confirm with deconvolution microscopy that MEP of rat mixed cerebellar cultures robustly increases synaptic NMDAR localization. Phospho-activation of the non-receptor tyrosine kinases Src and Pyk2, known to be linked to synaptic NMDAR, is also demonstrated. Additionally, the preconditioning enhances levels of an antioxidant protein, peroxiredoxin 2 (Prx2), reported to be downstream of synaptic NMDAR signaling, and NMDAR antagonism with memantine (earlier found to abrogate MEP neuroprotection) blocks the Prx2 elevations. To further link Prx2 with antioxidant-based neuroprotection, we circumvented the ethanol preconditioning-NMDAR pathway by pharmacologically increasing Prx2 with the naturally-occurring cruciferous compound, 3H-1,2-dithiole-3-thione (D3T). Thus, D3T pretreatment elevated Prx2 expression to a similar extent as MEP, while concomitantly preventing β-amyloid neurotoxicity; D3T also protected the cultures from hydrogen peroxide toxicity. The findings support a mechanism that couples synaptic NMDAR signaling, Prx2 expression and augmented antioxidant defenses in ethanol preconditioning-induced neuroprotection. That this mechanism can be emulated by a cruciferous vegetable constituent suggests that such naturally-occurring “neutraceuticals” may be useful in therapy for oxidative stress-related dementias.

Background. Infliximab (IFX) therapeutic drug monitoring (TDM) allows for objective decision making in patients with inflammatory bowel disease (IBD) and loss of response. Questions remain about whether IFX TDM improves outcomes. Methods. Patients with IBD who had IFX TDM due to concerns for loss of response were considered for inclusion. Serum IFX trough concentration and anti-drug antibody (ADA) concentrations were measured. Patients were grouped by TDM results: group 1, low IFX/high ADA; group 2, low IFX/low ADA; group 3, therapeutic IFX. Changes in management were analyzed according to groupings; remission rates were assessed at 6 months. Results. 71 patients were included of whom 37% underwent an appropriate change in therapy. Groups 1 (67%) and 2 (83%) had high adherence compared to only 9% in group 3. At 6 months, 57% had achieved remission. More patients who underwent an appropriate change in therapy achieved remission, though this did not reach statistical significance (69% versus 49%; P=0.098). Conclusions. A trend towards increased remission rates was associated with appropriate changes in management following TDM results. Many patients with therapeutic IFX concentrations did not undergo an appropriate change in management, potentially reflecting a lack of available out-of-class options at the time of TDM or due to uncertainty of the meaning of the reported therapeutic range.

BACKGROUND: Increasing prevalence of atrial fibrillation has a significant impact on health, society, and healthcare resource utilization, due to increased morbidity, mortality, risk of stroke, and reduction in quality of life. Early diagnosis allows for treatment initiation, a reduction in complications and associated costs, and so innovation to improve screening and enable easy access are needed Developments in digital technology have significantly contributed to the availability of screening tools. The single-lead electrocardiogram AliveCor (Mountainview, CA) device offers the opportunity to provide heart rhythm screening and has been used extensively in clinical practice and research studies. METHODS: This review investigates the feasibility, validity, and utility of the AliveCor device as a tool for atrial fibrillation detection in clinical practice and in wider research. Databases searched included PUBMED, CINAHL, MEDLINE, and World of Science, plus grey literature search. Search terms related to atrial fibrillation, screening, and AliveCor with adults >18 years. Feasibility metrics were applied including process, resource, management, and scientific outcomes. Studies not written in the English language were excluded. Validity of AliveCor was explored by extracting sensitivity and specificity data from eligible studies and overall effectiveness analyzed by incorporating the above, with wider issues surrounding screening approaches, cost effectiveness and appropriateness of AliveCor as a screening tool. RESULTS: The AliveCor device screening was reviewed in 11 studies matching inclusion criteria. Atrial fibrillation detection rates ranged from 0.8% to 36% and this largely correlated to the study population, where wider age inclusion and mass/population screening represented lower atrial fibrillation detection. Recruitment from higher-risk groups (older age, targeted localities, chronic disease) identified higher numbers with atrial fibrillation. Feasibility metrics demonstrated AliveCor as an effective tool of choice in terms of process, resources, and management. Duration of screening time had an impact on rates of atrial fibrillation detection. There was however significant heterogeneity between studies reviewed. CONCLUSION: The AliveCor device offers a convenient, valid, and feasible means of monitoring for atrial fibrillation. Further analysis of electrocardiograms produced by AliveCor may be necessary in some circumstances. The AliveCor electrocardiogram device can be successfully implemented into both opportunistic and systematic screening strategies for atrial fibrillation.

Regions within the Pale differ in their physical geographies supportive of human geographies. Each region has its own internal physical variations as well.

Background Tumor-associated macrophages (TAMs) are important determinants of intratumoral immune evasion, neoangiogenesis, extracellular matrix remodeling and dysregulated tumor cell proliferation. Our prior studies revealed that macrophage-derived, but not tumor cell-derived, macrophage migration inhibitory factor (MIF), is an important determinant of TAM alternative activation and M2 polarization. Aim Because MIF is historically thought to initiate signaling via a receptor-dependent, outside-in mode of action, we wished to investigate the specific contributions of tumor-derived vs. macrophage-derived MIF to M2 marker expression during macrophage polarization. Design Murine oral squamous cell-carcinoma cells (SCCVII) were co-cultured with either the RAW 264.7 mouse macrophage cell line or mouse primary bone marrow-derived macrophages in the context of MIF genetic loss/inhibition individually or in combination each cell type. Methods Twelve well Transwell plates were used to co-culture SCCVII cells and RAW 264.7, MIF+/+ or MIF-/- macrophages treated with/without the small molecule MIF inhibitor, 4-iodo-6-phenylpyrimidine and incubated in the presence or absence of interleukin (IL-4) for 48 h. Macrophages were analyzed by quantitative real-time polymerase chain reaction and/or immunoblotting for relative macrophage polarization marker expression. Results IL-4 treatment synergizes with SCCVII co-culture in inducing the expression of macrophage M2 markers and loss or inhibition of macrophage-derived MIF significantly reduces both IL-4 alone and IL-4/SCCVII co-culture-induced macrophage M2 marker expression. Conclusion These studies identify an important and dominant requirement for macrophage MIF in maximal Th2-cytokine and oral squamous carcinoma cell-induced macrophage polarization and M2 marker expression.

In this study we show Yersinia pseudotuberculosis secretes membrane vesicles (MVs) that contain different proteins and virulence factors depending on the strain. Although MVs from Y. pseudotuberculosis YPIII and ATCC 29833 had many proteins in common (68.8% of all the proteins identified), those located in the outer membrane fraction differed significantly. For instance, the MVs from Y. pseudotuberculosis YPIII harbored numerous Yersinia outer proteins (Yops) while they were absent in the ATCC 29833 MVs. Another virulence factor found solely in the YPIII MVs was the cytotoxic necrotizing factor (CNFy), a toxin that leads to multinucleation of host cells. The ability of YPIII MVs to transport this toxin and its activity to host cells was verified using HeLa cells, which responded in a dose-dependent manner; nearly 70% of the culture was multinucleated after addition of 5 µg/ml of the purified YPIII MVs. In contrast, less than 10% were multinucleated when the ATCC 29833 MVs were added. Semi-quantification of CNFy within the YPIII MVs found this toxin is present at concentrations of 5 ~ 10 ng per µg of total MV protein, a concentration that accounts for the cellular responses seen.