The emerging oral pathogen, Filifactor alocis, modulates antimicrobial responses in primed human neutrophils.

Periodontitis is an irreversible, chronic inflammatory, infectious disease of the oral cavity that affects approximately half of all adults 30 years or older in the USA. The oral cavity is under high immune surveillance because of its constant exposure to microbes in the environment. The primary immune cell responsible for this surveillance is the neutrophil. Pathogens associated with periodontitis possess virulence factors and have evolved strategies to evade neutrophil antimicrobial responses to survive. One such pathogen is Filifactor alocis, whose presence is associated with the progression of periodontitis. F. alocis manipulates several neutrophil antimicrobial functional responses to avoid killing, an evasion strategy that might perpetuate the unresolved destructive inflammation that is the hallmark of periodontitis. An essential aspect of the host immune response against a threat is the release of cytokines and chemokines, a wide array of small endogenous inflammatory mediators that communicate between cells and evoke different responses from the cells, contributing to the initiation and resolution of the inflammatory response. Specific inflammatory cytokines and chemokines are associated with inflammation of the periodontium, a specialized tissue that surrounds and supports the tooth structure. These inflammatory mediators can prime or preactivate quiescent neutrophils. A primed neutrophil will display an enhanced response to a secondary stimulus compared to a quiescent or unprimed cell. Besides endogenous priming agents, exogenous agents such as the lipopolysaccharide (LPS) from bacteria can prime neutrophils via pattern recognition toll-like receptors (TLRs). This project aims to define if F. alocis modulates the antimicrobial responses of primed neutrophils to promote its survival and the progression of periodontitis. In this project, two endogenous priming agents, tumor necrosis (TNF)α and interleukin (IL)-8, and LPS as an exogenous priming agent, were tested. LPS stimulates TLR4, but if the preparation contains additional bacterial components like lipoproteins, it also stimulates TLR2. To assess the response of LPS-primed neutrophils toward F. alcois, three sources of LPS were used as priming agents for this project: Escherichia coli LPS-EK (containing lipoproteins), E. coli LPS-EK Ultrapure (no lipoproteins), and LPS from the keystone periodontal pathogen, Porphyromonas gingivalis. The data showed that F. alocis internalization was significantly increased in TNFa and both forms of tested E. coli LPS primed neutrophils compared to unprimed cells, both by flow cytometry and confocal microscopy. In contrast, phagocytosis of F. alocis was similar between unprimed or IL-8 primed neutrophils. Interestingly, the respiratory burst response elicited by F. alocis was similar between unprimed and neutrophils primed by TNFα, IL-8, or E. coli LPS. However, P. gingivalis LPS was unable to prime neutrophils. These findings suggest that although TNFα and LPS primed neutrophils have enhanced phagocytosis towards F. alocis, it does not result in enhanced respiratory burst response. These results suggest that F. alocis can disable one of the phagocyte\u27s critical antimicrobial functions, the respiratory burst response, to evade killing. Another exciting finding suggests that F. alocis might modulate the IL-8 signaling pathway to prevent internalization. Preliminary data also suggest that priming neutrophils with TNFα did not enhance the killing of F. alocis. In summary, the observed modulations of primed neutrophil antimicrobial responses by F. alocis may represent one of the organisms\u27 evasion strategies to survive neutrophils in the hostile inflamed periodontal tissue

The emerging oral pathogen, Filifactor alocis, modulates antimicrobial responses of primed human neutrophils.

Almost 50% of the adult population older than 30 years of age suffers from some form of periodontitis, a chronic inflammatory disease of the periodontal tissue caused by microbial subversion of the host immune response. Neutrophils are the most abundant leukocyte present in the oral mucosa. In periodontitis, periodontal pathogens have developed strategies to evade neutrophil antimicrobial responses and promote bacterial growth. Among these oral pathogens is Filifactor alocis which can modulate neutrophils’ antimicrobial responses by preventing phagosome maturation. During inflammation, neutrophils that reach the gingival tissue are primed by cytokines and chemokines. However, the response of primed human neutrophils to F. alocis is currently unknown. To address this gap in knowledge, human neutrophils were primed with TNF-α, an established priming agent, and the kinetics of phagocytosis and intracellular ROS production in response to serum opsonized F. alocis were tested. Our results showed a significant increase in phagocytosis of F. alocisby TNF-α-primed neutrophils compared to unprimed cells. However, the significant increase in bacteria uptake was not accompanied by increased ROS production. F. alocis significantly downregulated the respiratory burst response in human neutrophils independently of priming with TNF-α. Interestingly, priming of neutrophils with IL-8 did not result in a significant increase in phagocytosis of F. alocis, but IL-8-primed neutrophils did have a similar ROS phenotype to TNF-α-primed neutrophils. This suggests dome ability of F. alcois to modulate the phagocytic ability of IL-8-primed neutrophils. Future studies will aim to characterize F. alocis’ virulence factors that modulate neutrophil responses

Diagnosis of breast cancer using elastic-scattering spectroscopy: preliminary clinical results

We report on the first stages of a clinical study designed to test elastic-scattering spectroscopy, mediated by fiberoptic probes, for three specific clinical applications in breast-tissue diagnosis: (1) a transdermal-needle (interstitial) measurement for instant diagnosis with minimal invasiveness similar to fine-needle aspiration but with sensitivity to a larger tissue volume, (2) a hand-held diagnostic probe for use in assessing tumor/resection margins during open surgery, and (3) use of the same probe for real-time assessment of the `sentinel' node during surgery to determine the presence or absence of tumor (metastatic). Preliminary results from in vivo measurements on 31 women are encouraging. Optical spectra were measured on 72 histology sites in breast tissue, and 54 histology sites in sentinel nodes. Two different artificial intelligence methods of spectral classification were studied. Artificial neural networks yielded sensitivities of 69% and 58%, and specificities of 85% and 93%, for breast tissue and sentinel nodes, respectively. Hierarchical cluster analysis yielded sensitivities of 67% and 91%, and specificities of 79% and 77%, for breast tissue and sentinel nodes, respectively. These values are expected to improve as the data sets continue to grow and more sophisticated data preprocessing is employed. The study will enroll up to 400 patients over the next two years

Effect of Duration and Intermittency of Rifampin on Tuberculosis Treatment Outcomes: A Systematic Review and Meta-Analysis

In a systematic review of randomized controlled trials on tuberculosis treatment, Dick Menzies and colleagues find shorter courses of rifampin to be associated with poorer treatment outcomes

ST2 and IL-33 in Pregnancy and Pre-Eclampsia

Normal pregnancy is associated with a mild systemic inflammatory response and an immune bias towards type 2 cytokine production, whereas pre-eclampsia is characterized by a more intense inflammatory response, associated with endothelial dysfunction and a type 1 cytokine dominance. Interleukin (IL)-33 is a newly described member of the IL-1 family, which binds its receptor ST2L to induce type 2 cytokines. A soluble variant of ST2 (sST2) acts as a decoy receptor to regulate the activity of IL-33. In this study circulating IL-33 and sST2 were measured in each trimester of normal pregnancy and in women with pre-eclampsia. While IL-33 did not change throughout normal pregnancy, or between non-pregnant, normal pregnant or pre-eclamptic women, sST2 was significantly altered. sST2 was increased in the third trimester of normal pregnancy (p<0.001) and was further increased in pre-eclampsia (p<0.001). This increase was seen prior to the onset of disease (p<0.01). Pre-eclampsia is a disease caused by placental derived factors, and we show that IL-33 and ST2 can be detected in lysates from both normal and pre-eclampsia placentas. ST2, but not IL-33, was identified on the syncytiotrophoblast layer, whereas IL-33 was expressed on perivascular tissue. In an in vitro placental perfusion model, sST2 was secreted by the placenta into the ‘maternal’ eluate, and placental explants treated with pro-inflammatory cytokines or subjected to hypoxia/reperfusion injury release more sST2, suggesting the origin of at least some of the increased amounts of circulating sST2 in pre-eclamptic women is the placenta. These results suggest that sST2 may play a significant role in pregnancies complicated by pre-eclampsia and increased sST2 could contribute to the type 1 bias seen in this disorder

New genetic loci link adipose and insulin biology to body fat distribution.

Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms

Examining the generalizability of research findings from archival data

This initiative examined systematically the extent to which a large set of archival research findings generalizes across contexts. We repeated the key analyses for 29 original strategic management effects in the same context (direct reproduction) as well as in 52 novel time periods and geographies; 45% of the reproductions returned results matching the original reports together with 55% of tests in different spans of years and 40% of tests in novel geographies. Some original findings were associated with multiple new tests. Reproducibility was the best predictor of generalizability—for the findings that proved directly reproducible, 84% emerged in other available time periods and 57% emerged in other geographies. Overall, only limited empirical evidence emerged for context sensitivity. In a forecasting survey, independent scientists were able to anticipate which effects would find support in tests in new samples

Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries

Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P &lt; 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely