Social Network Analysis of Intensive Care Unit Health Care Professionals Measured by Wearable Sociometric Badges: Longitudinal Observational Study.

BACKGROUND: Use of wearable sensor technology for studying human teamwork behavior is expected to generate a better understanding of the interprofessional interactions between health care professionals. OBJECTIVE: We used wearable sociometric sensor badges to study how intensive care unit (ICU) health care professionals interact and are socially connected. METHODS: We studied the face-to-face interaction data of 76 healthcare professionals in the ICU at Mie University Hospital collected over 4 weeks via wearable sensors. RESULTS: We detail the spatiotemporal distributions of staff members' inter- and intraprofessional active face-to-face interactions, thereby generating a comprehensive visualization of who met whom, when, where, and for how long in the ICU. Social network analysis of these active interactions, concomitant with centrality measurements, revealed that nurses constitute the core members of the network, while doctors remain in the periphery. CONCLUSIONS: Our social network analysis using the comprehensive ICU interaction data obtained by wearable sensors has revealed the leading roles played by nurses within the professional communication network.

Incidence and Risk Factors of Postoperative Delirium following Pancreatic Surgery: Does the Administration of TJ-54 Reduce the Incidence of Delirium.

PURPOSES: To clarify the incidence and risk factors of postoperative delirium in patients following pancreatic surgery, and the impact of yokukansan (TJ-54) administered to reduce delirium. METHODS: Fifty-nine consecutive patients who underwent pancreatic surgery (2012.4-2013.5) were divided into 2 groups: TJ-54 group: patients who received TJ-54 (n = 21) due to insomnia and the No-TJ-54 group: patients who did not receive TJ-54 (n = 38), and the medical records including the delirium rating scale - Japanese version (DRS-J) were retrospectively reviewed. RESULTS: Postoperative delirium occurred in 2 patients (9.5%) in the TJ-54 group and in 4 (10.5%) patients in the No-TJ-54 group (p = 0.90). The DRS-J on 5 days after surgery was lower in the TJ-54 group than in the No-TJ-54 group (rough p = 0.006), however, without any statistically significant differences with the Bonferroni correction. As for the hospital cost, there was no difference between the TJ-54 and the No-TJ-54 groups (p = 0.78). History of delirium was identified as an independent risk factor of postoperative delirium. CONCLUSION: The patients with preoperative insomnia, who were treated with TJ-54, did not have a higher incidence of postoperative delirium, compared to those without preoperative insomnia. The patients who had a history of delirium have an increased risk of postoperative delirium and should be cared for and treated prophylactically to prevent it.

Chemokine receptor CCR8 is required for lipopolysaccharide-triggered cytokine production in mouse peritoneal macrophages.

Chemokine (C-C motif) receptor 8 (CCR8), the chemokine receptor for chemokine (C-C motif) ligand 1 (CCL1), is expressed in T-helper type-2 lymphocytes and peritoneal macrophages (PMφ) and is involved in various pathological conditions, including peritoneal adhesions. However, the role of CCR8 in inflammatory responses is not fully elucidated. To investigate the function of CCR8 in macrophages, we compared cytokine secretion from mouse PMφ or bone marrow-derived macrophages (BMMφ) stimulated with various Toll-like receptor (TLR) ligands in CCR8 deficient (CCR8-/-) and wild-type (WT) mice. We found that CCR8-/- PMφ demonstrated attenuated secretion of tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-10 when stimulated with lipopolysaccharide (LPS). In particular, LPS-induced IL-10 production absolutely required CCR8. CCR8-dependent cytokine secretion was characteristic of PMφ but not BMMφ. To further investigate this result, we selected the small molecule compound R243 from a library of compounds with CCR8-antagonistic effects on CCL1-induced Ca2+ flux and CCL1-driven PMφ aggregation. Similar to CCR8-/- PMφ, R243 attenuated secretion of TNF-α, IL-6, and most strikingly IL-10 from WT PMφ, but not BMMφ. CCR8-/- PMφ and R243-treated WT PMφ both showed suppressed c-jun N-terminal kinase activity and nuclear factor-κB signaling after LPS treatment when compared with WT PMφ. A c-Jun signaling pathway inhibitor also produced an inhibitory effect on LPS-induced cytokine secretion that was similar to that of CCR8 deficiency or R243 treatment. As seen in CCR8-/- mice, administration of R243 attenuated peritoneal adhesions in vivo. R243 also prevented hapten-induced colitis. These results are indicative of cross talk between signaling pathways downstream of CCR8 and TLR-4 that induces cytokine production by PMφ. Through use of CCR8-/- mice and the new CCR8 inhibitor, R243, we identified a novel macrophage innate immune response pathway that involves a chemokine receptor.

Sensitivity of Hep G2 cells to Bacillus cereus emetic toxin.

We herein examined the sensitivity of Hep G2 human hepatoma cells to Bacillus cereus emetic toxin. Hep G2 cells were treated with the emetic toxin, and the cell shape was observed. The same experiments were performed for comparison purposes, using HEp-2 cells, which are currently used by most laboratories for a bioassay of the emetic toxin. Hep G2 cells showed clearer vacuolation in the cytosol within 2 hr and required a shorter incubation period than HEp-2 cells (10 hr). The number of vacuoles in the Hep G2 cells was greater, and the size of the vacuoles was larger than those observed in HEp-2 cells. The minimal concentration of the emetic toxin required to induce the vacuolation of Hep G2 cells was 0.04 ng/ml. The concentration for the HEp-2 cells was 1 ng/ml. These findings indicate that Hep G2 cells show higher sensitivity to the emetic toxin. Hep G2 cells may be superior to the currently used HEp-2 cells for the bioassay of the emetic toxin.

Comprehensive analysis of chemokines and cytokines secreted in the peritoneal cavity during laparotomy.

We recently found that chemokine-driven peritoneal cell aggregation is the primary mechanism of postoperative adhesion in a mouse model. To investigate this in humans, paired samples of peritoneal lavage fluid were obtained from seven patients immediately after incision (preoperative) and before closure (postoperative), and were assayed for the presence of 27 cytokines and chemokines using multiplex beads assay. As a result, IL-6 and CCL5 showed the most striking increase during operation. Recombinant CCL5 or lavage fluid induced chemotaxis of human peripheral blood mononuclear cells. We propose that CCL5 is possibly involved in the mechanism of postoperative adhesion in humans.

Dose-dependent differential regulation of cytokine secretion from macrophages by fractalkine.

Although expression of the fractalkine (CX3CL1, FKN) is enhanced in inflamed tissues, it is detected at steady state in various organs such as the intestine, and its receptor CX3CR1 is highly expressed in resident-type dendritic cells and macrophages. We hypothesized that FKN might regulate the inflammatory responses of these cells. Therefore, murine macrophages were pretreated with FKN and then stimulated with LPS. We found that macrophages pretreated with 0.03 nM FKN but not with 3 nM FKN secreted 50% less TNF-alpha than did cells treated with LPS alone. Cells treated with 0.03 nM FKN and LPS also showed reduced phosphorylation of ERK1/2 and reduced NF-kappaB p50 subunit. Interestingly, the p65 subunit of NF-kappaB was translocated to the nuclei but redistributed to the cytoplasm in the early phase by forming a complex with peroxisome proliferator-activated receptor (PPAR) gamma. Exogenous 15-deoxy-Delta(12,14)-prostaglandin J2, a natural ligand for PPAR-gamma, also induced redistribution of p65 with decreased TNF-alpha secretion after LPS challenge. Pretreatment with 0.03 nM but not 3 nM FKN increased the cellular levels of 15-deoxy-Delta(12,14)-prostaglandin J2 as well as mRNA of PPAR-gamma. Requirement of PPAR-gamma for the effect of 0.03 nM FKN was confirmed by small interfering RNA of PPAR-gamma. In contrast, pretreatment with 3 nM FKN induced higher levels of IL-23 compared with cells pretreated with 0.03 nM FKN and produced TNF-alpha in a CX3CR1-dependent manner. These dose-dependent differential effects of FKN establish its novel role in immune homeostasis and inflammation.

IL-13 receptor alpha2 promotes epithelial cell regeneration from radiation-induced small intestinal injury in mice.

BACKGROUND & AIMS: The cytokines interleukin (IL)-4 and IL-13 have pleiotropic effects on a variety of cell types and impact both pathologic changes and tissue remodeling. The aim of this study was to clarify the roles of IL-13 receptor alpha2 (IL-13Ralpha2), which is the high-affinity decoy receptor for IL-13, in gastrointestinal tract epithelial cell turnover and repair. METHODS: We have compared the regenerative process following mucosal damage induced by whole-body 3-Gy X-ray irradiation of wild-type (WT) and IL-4 receptor alpha gene-deficient (IL-4R(-/-)) mice. Then we treated mice with IL-13Ralpha2 human immunoglobulin (Ig) chimeric protein. RESULTS: Up-regulation of mRNA levels for IL-13 in NK cells in the lamina propria was seen after irradiation of WT mice. Concomitant with vigorous epithelial cell division in the jejunum following irradiation, expression of the IL-13Ralpha2 dramatically increased in myofibroblasts and fibroblasts. In contrast, epithelial cell repair was delayed in IL-4R(-/-) mice, which did not show transient up-regulation of IL-13Ralpha2, although up-regulation of IL-13 was seen. Addition of IL-13 but not IL-4 to primary cultures of small intestine from both WT and IL-4R(-/-) mice induced epithelial cell damage. Treatment of IL-4R(-/-) mice with IL-13Ralpha2-Ig resulted in increased numbers of dividing epithelial cells and improved tissue repair after irradiation. Further, treatment with IL-13Ralpha2-Ig increased numbers of microcolonies of regenerating epithelial cells in the intestine of WT mice after severe damage induced by 12-Gy irradiation. CONCLUSIONS: The IL-13Ralpha2 is a major regulatory factor involved in the regeneration of epithelial cells in the gastrointestinal tract.

Endoglin (CD105) is a target for an oral DNA vaccine against breast cancer.

Endoglin (CD105), a co-receptor in the TGF-beta receptor complex, is over-expressed on proliferating endothelial cells in the breast tumor neovasculature and thus offers an attractive target for anti-angiogenic therapy. Here we report the anti-angiogenic/anti-tumor effects achieved in a prophylactic setting with an oral DNA vaccine encoding murine endoglin, carried by double attenuated Salmonella typhimurium (dam-, AroA-) to a secondary lymphoid organ, i.e., Peyer's patches . We demonstrate that an endoglin vaccine elicited activation of antigen-presenting dendritic cells, coupled with immune responses mediated by CD8+ T cells against endoglin-positive target cells. Moreover, we observed suppression of angiogenesis only in mice administered with the endoglin vaccine as compared to controls. These data suggest that a CD8+ T cell-mediated immune response induced by this vaccine effectively suppressed dissemination of pulmonary metastases of D2F2 breast carcinoma cells presumably by eliminating proliferating endothelial cells in the tumor vasculature. It is anticipated that vaccine strategies such as this may contribute to future therapies for breast cancer.

DNA-based vaccines activate innate and adaptive antitumor immunity by engaging the NKG2D receptor.

The interaction of NKG2D, a stimulatory receptor expressed on natural killer (NK) cells and activated CD8(+) T cells, and its ligands mediates stimulatory and costimulatory signals to these cells. Here, we demonstrate that DNA-based vaccines, encoding syngeneic or allogeneic NKG2D ligands together with tumor antigens such as survivin or carcinoembryonic antigen, markedly activate both innate and adaptive antitumor immunity. Such vaccines result in highly effective, NK- and CD8(+) T cell-mediated protection against either breast or colon carcinoma cells in prophylactic and therapeutic settings. Notably, this protection was irrespective of the NKG2D ligand expression level of the tumor cells. Hence, this strategy has the potential to lead to widely applicable and possibly clinically useful DNA-based cancer vaccines.

T cell-mediated suppression of angiogenesis results in tumor protective immunity.

Antiangiogenic intervention is known to inhibit tumor growth and dissemination by attacking the tumor's vascular supply. Here, we report that this was achieved for the first time using an oral DNA minigene vaccine against murine vascular endothelial growth factor receptor 2 (FLK-1), a self-antigen overexpressed on proliferating endothelial cells in the tumor vasculature. Moreover, we identified the first H-2Db-restricted epitope, FLK400 (VILT-NPISM), specifically recognized by cytotoxic T lymphocytes (CTLs). Such CTLs were capable of killing FLK-1+ endothelial cells, resulting in suppression of angiogenesis and long-lived tumor protection. The specificity of this immune response was indicated because the DNA vaccine encoding the entire FLK-1 gene also induced a FLK400-specific CTL response. This minigene vaccine strategy provides a more flexible alternative to whole-gene vaccination and facilitates in-depth mechanism studies to tailor DNA vaccines for optimal T-cell activation and tumor protection.

A DNA vaccine targeting Fos-related antigen 1 enhanced by IL-18 induces long-lived T-cell memory against tumor recurrence.

A novel vaccination strategy induced specific CD8(+) T cell-mediated immunity that eradicated spontaneous and experimental pulmonary cancer metastases in syngeneic mice and was also effective in a therapeutic setting of established breast cancer metastases. This was achieved by targeting transcription factor Fos-related antigen 1(Fra-1), overexpressed by many tumor cells, with an ubiquitinated DNA vaccine against Fra-1, coexpressing secretory IL-18. Insight into the immunologic mechanisms involved was provided by adoptive transfer of T lymphocytes from successfully immunized BALB/c mice to syngeneic severe combined immunodeficient (SCID) mice. Specifically, long-lived T memory cells were maintained dormant in nonlymphoid tissues by IL-18 in the absence of tumor antigen. Importantly, a second tumor cell challenge of these SCID mice restored both, robust tumor-specific cytotoxicity and long-lived T-cell memory, capable of eradicating established pulmonary cancer metastases, suggesting that this vaccine could be effective against tumor recurrence.

Therapeutic potential of follistatin for colonic inflammation in mice.

BACKGROUND AND AIMS: Activins belong to the transforming growth factor-beta superfamily. Recent studies have shown that activin and its natural antagonist, follistatin, are involved in tissue repair and inflammatory processes. The aim of this study was to determine whether neutralization of activins with follistatin would have an in vivo anti-inflammatory effect in several murine models of colitis. METHODS: We assessed activin levels in the colitis induced by intracolonic administration of trinitrobenzene sulfonic acid (TNBS). We subsequently tested the effects of an intraperitoneal injection of follistatin before or after induction of TNBS colitis. We also examined the established colitis induced by oral dextran sulfate sodium (DSS) as well as the spontaneous colitis that develops in interleukin (IL)-10 gene-deficient (IL-10 -/- ) mice. RESULTS: Levels of activin transcripts in the colon during the acute phase of TNBS colitis were up-regulated. Epithelial cells, infiltrating macrophages (Mvarphi), and endothelial cells produced excess activin betaA. Pretreatment with follistatin increased the survival rate of mice with TNBS colitis from 33% to 82% and decreased the plasma levels of IL-6 and amyloid A. Administration of follistatin also reduced the histologic score and tissue myeloperoxidase activity in established TNBS and DSS colitis and reduced the severity of the colitis in IL-10 -/- mice. Based on results obtained from 3 mouse models and from in vitro experiments, follistatin promoted the proliferation of colonic epithelial cells. CONCLUSIONS: Neutralization of activins by follistatin promoted epithelial cell division and tissue repair, clearly suggesting a treatment modality for intestinal inflammation.

A DNA vaccine targeting survivin combines apoptosis with suppression of angiogenesis in lung tumor eradication.

A novel strategy achieved the eradication of lung tumor metastases by joint suppression of angiogenesis in the tumor neovasculature and induction of tumor cell apoptosis. This was accomplished by CTLs induced by a DNA vaccine encoding secretory chemokine CCL21 and the inhibitor of apoptosis protein survivin, overexpressed by both proliferating endothelial cells in the tumor vasculature and tumor cells. Oral delivery of this DNA vaccine by doubly attenuated Salmonella typhimurium (dam(-) and AroA(-)) to such secondary lymphoid organs as Peyer's patches in the small intestine, elicited marked activation of antigen-presenting dendritic cells, and an effective CD8(+)T cell immune response against the survivin self-antigen. This resulted in eradication or suppression of pulmonary metastases of non-small cell lung carcinoma in both prophylactic and therapeutic settings in C57BL/6J mice. Moreover, the suppression of angiogenesis induced by the vaccine did not impair wound healing or fertility of treated mice. It is anticipated that such novel DNA vaccines will aid in the rational design of future strategies for the prevention and treatment of cancer.

Expression of PAC1 receptor in rat thymus after irradiation.

In the present work, PAC1-R (G-protein-coupled receptor specific for PACAP) was detected on cells in the normal thymus. Immunohistochemically PAC1-R was expressed strongly in stromal cells of the thymic medulla. Positive cells were also observed in the thymus of fetal and old adult rats. After 8 Gy irradiation to 9-week-old rats, PAC1-R expressions in the thymus decreased and almost recovered by day 21. The expression of PAC1-R mRNA was weak in the thymus and decreased further after irradiation. The expression almost recovered by day 28. Hip and hip/hop variants, which were not expressed in the normal thymus, were expressed in the thymus on days 3, 5 and 21 after irradiation. The expressions of IL-6 and IL-10 tended to increase initially after irradiation then decreased. Histologically, the thymic structures were destroyed on day 3 after irradiation and the thymus almost recovered by day 21. Thus PACAP is thought to be one of the important factors for cross-talk between cells involved in thymic regeneration.

A novel transgenic mouse model for immunological evaluation of carcinoembryonic antigen-based DNA minigene vaccines.

A lack of relevant animal models has hampered preclinical screening and critical evaluation of the efficacy of human vaccines in vivo. Carcinoembryonic antigen-A2Kb (CEA-A2Kb) double transgenic mice provide a biologically relevant model for preclinical screening and critical evaluation of human CEA vaccine efficacy in vivo, particularly because such animals are peripherally tolerant of CEA. We established the utility of this model by demonstrating that an oral DNA minigene vaccine induces effective HLA-A2-restricted, CEA-specific antitumor CTL responses. This finding is supported by three lines of evidence: (a). an effective HLA-A2-restricted, CEA(691)-specific CTL response; (b). specific in vitro killing of CEA-A2Kb transduced MC-38 colon carcinoma cells; and (c). protective immunity induced in vaccinated mice against challenges of these tumor cells. Importantly, peripheral T cell tolerance against CEA in CEA-A2Kb double transgenic mice was broken by the CEA(691) (IMIGVLVGV) minigene vaccine. In conclusion, CEA-A2Kb double transgenic mice were demonstrated to be good candidates for in vivo testing of human CEA-based vaccines. This result suggests a potential for these vaccines in future human vaccine development. The feasibility of using nonmutated self-antigens as targets for therapeutic vaccinations was indicated, provided that such antigens are presented in an immunogenic context; that is, as a DNA minigene in a bacterial carrier system.

Transcription factor Fos-related antigen 1 is an effective target for a breast cancer vaccine.

Protection against breast cancer was achieved with a DNA vaccine against murine transcription factor Fos-related antigen 1, which is overexpressed in aggressively proliferating D2F2 murine breast carcinoma. Growth of primary s.c. tumor and dissemination of pulmonary metastases was markedly suppressed by this oral DNA vaccine, carried by attenuated Salmonella typhimurium, encoding murine Fos-related antigen 1, fused with mutant polyubiquitin, and cotransformed with secretory murine IL-18. The life span of 60% of vaccinated mice was tripled in the absence of detectable tumor growth after lethal tumor cell challenge. Immunological mechanisms involved activation of T, natural killer, and dendritic cells, as indicated by up-regulation of their activation markers and costimulatory molecules. Markedly increased specific target cell lysis was mediated by both MHC class I-restricted CD8+ T cells and natural killer cells isolated from splenocytes of vaccinated mice, including a significant release of proinflammatory cytokines IFN-gamma and IL-2. Importantly, fluorescence analysis of fibroblast growth factor 2 and tumor cell-induced vessel growth in Matrigel plugs demonstrated marked suppression of angiogenesis only in vaccinated animals. Taken together, this multifunctional DNA vaccine proved effective in protecting against growth and metastases of breast cancer by combining the action of immune effector cells with suppression of tumor angiogenesis.

Inflammatory and anti-inflammatory cytokines regulate the recovery from sublethal X irradiation in rat thymus.

We investigated the regeneration of rat thymus after sublethal X irradiation (6 Gy). The number of thymocytes was much lower on day 3 after irradiation, and many apoptotic cells were observed. However, by day 5, there had been a rapid proliferation of thymocytes. Since cytokines are considered to be important regulatory factors in postirradiation recovery, we performed in vivo cytokine assays using semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) and found serial changes in the cytokine message. The messenger RNA (mRNA) expression of the pro-inflammatory cytokines interleukin 1 beta (Il1b), Il6 and tumor necrosis factor alpha (Tnf) was higher than normal on day 3, lower on day 5, and higher again on day 7. In particular, Tnf was completely absent on day 5 and was expressed again on day 7. Of the anti-inflammatory cytokines Il4, transforming growth factor beta (Tgfb) and Il10, only the Il10 message changed substantially. Il10 expression was very high on day 5 but was completely absent on day 7. Thus the Tnf and Il10 messages were expressed alternately. The changes in the distribution of macrophages detected by the immunohistochemical analysis may be related to the changes in the cytokines. Analysis of cytokine messages in the regenerating thymus in vivo may provide new insights into potential therapies for radiation-induced damage.