Dextran sodium sulfate potentiates NLRP3 inflammasome activation by modulating the KCa3.1 potassium channel in a mouse model of colitis.

Inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis, has increased in incidence and prevalence in recent decades. Both clinical and animal studies are critical for understanding the pathogenesis of this disease. Dextran sodium sulfate (DSS)-induced colitis is a frequently used animal model of IBD, but the underlying mechanism of the model remains incompletely understood. In this study, we found that NOD-like receptor family pyrin containing 3 (NLRP3) depletion markedly mitigated DSS-induced colitis and was accompanied by decreased activation of the inflammasome in the colons of mice. However, in vitro assays showed that DSS did not directly trigger but instead potentiated NLRP3 inflammasome assembly in macrophages in response to suboptimal ATP or nigericin stimulation. Mechanistically, DSS potentiated NLRP3 inflammasome activation in macrophages by augmenting KCa3.1-mediated potassium ion (K+) efflux. Furthermore, we found that pharmacologic blockade of the K+ channel KCa3.1 with TRAM-34 or genetic depletion of the Kcnn4 gene (encoding KCa3.1) not only ameliorated the severity of DSS-induced colitis but also attenuated in vivo inflammasome assembly in the colonic tissues of mice, suggesting a causal link between KCa3.1-mediated augmentation of the NLRP3 inflammasome and DSS-induced inflammatory injuries. Collectively, these results indicate that KCa3.1 plays a critical role in mediating DSS-induced colitis in mice by potentiating NLRP3 inflammasome activation. Our data provide a previously unknown mechanism by which DSS induces colitis in mice and suggests that KCa3.1 is an alternative therapeutic target for treating IBD.

Baicalin inhibits necroptosis by decreasing oligomerization of phosphorylated MLKL and mitigates caerulein-induced acute pancreatitis in mice.

Necroptosis is a form of regulated necrosis mainly controlled by receptor-interacting protein kinases 3 (RIPK3) and mixed lineage kinase domain-like protein (MLKL). Necroptosis has important roles in defensing against pathogenic infections, but it is also implicated in various inflammatory diseases including pancreatitis. Baicalin, a flavonoid from Scutellaria baicalensis Georgi, has been shown to possess anti-inflammatory and anti-pyroptosis properties, yet it is unclear whether baicalin can inhibit necroptosis and confer protection against necroptosis-related diseases. Here we reported that baicalin significantly inhibited necroptosis in macrophages induced by lipopolysaccharide plus pan-caspase inhibitor (IDN-6556), or by tumor-necrosis factor-α in combination with LCL-161 (Smac mimetic) and IDN-6556 (TSI). Mechanistically, baicalin did not inhibit the phosphorylation of RIPK1, RIPK3 and MLKL, nor membrane translocation of p-MLKL, during necroptotic induction, but instead inhibited p-MLKL oligomerization that is required for executing necroptosis. As intracellular reactive oxygen species (ROS) has been reported to be involved in p-MLKL oligomerization, we assessed the effects of N-acetyl-L-cysteine (NAC), an ROS scavenger, on necroptosis and found that NAC significantly attenuated TSI-induced necroptosis and intracellular ROS production concomitantly with reduced levels of oligomerized p-MLKL, mirroring the effect of baicalin. Indeed, inhibitory effect of baicalin was associated with reduced TSI-induced superoxide (indicating mitochondrial ROS) production and increased mitochondrial membrane potential within cells during necroptosis. Besides, oral administration of baicalin significantly reduced the severity of caerulein-induced acute pancreatitis in mice, an animal model of necroptosis-related disease. Collectively, baicalin can inhibit necroptosis through attenuating p-MLKL oligomerization and confers protection against caerulein-induced pancreatitis in mice.

Induction of multiple subroutines of regulated necrosis in murine macrophages by natural BH3-mimetic gossypol.

Macrophages are critical sentinel cells armed with multiple regulated necrosis pathways, including pyroptosis, apoptosis followed by secondary necrosis, and necroptosis, and are poised to undergo distinct form(s) of necrosis for tackling dangers of pathogenic infection or toxic exposure. The natural BH3-mimetic gossypol is a toxic phytochemical that can induce apoptosis and/or pyroptotic-like cell death, but what exact forms of regulated necrosis are induced remains largely unknown. Here we demonstrated that gossypol induces pyroptotic-like cell death in both unprimed and lipopolysaccharide-primed mouse bone marrow-derived macrophages (BMDMs), as evidenced by membrane swelling and ballooning accompanied by propidium iodide incorporation and lactic acid dehydrogenase release. Notably, gossypol simultaneously induces the activation of both pyroptotic and apoptotic (followed by secondary necrosis) pathways but only weakly activates the necroptosis pathway. Unexpectedly, gossypol-induced necrosis is independent of nucleotide-binding oligomerization domain-like receptor family pyrin domain containing 3 (NLRP3) inflammasome, as neither inhibitor for the NLRP3 pathway nor NLRP3 deficiency protects the macrophages from the necrosis. Furthermore, necrotic inhibitors or even pan-caspase inhibitor alone does not or only partly inhibit such necrosis. Instead, a combination of inhibitors composed of pan-caspase inhibitor IDN-6556, RIPK3 inhibitor GSK'872 and NADPH oxidase inhibitor GKT137831 not only markedly inhibits the necrosis, with all apoptotic and pyroptotic pathways being blocked, but also attenuates gossypol-induced peritonitis in mice. Lastly, the activation of the NLRP3 pathway and apoptotic caspase-3 appears to be independent of each other. Collectively, gossypol simultaneously induces the activation of multiple subroutines of regulated necrosis in macrophages depending on both apoptotic and inflammatory caspases.

Taraxasterol mitigates Con A-induced hepatitis in mice by suppressing interleukin-2 expression and its signaling in T lymphocytes.

Discovery of anti-inflammatory drugs that can suppress T lymphocyte activation and proliferation by inhibiting TCR/CD3 and IL-2/IL-2R signaling is still needed in clinic, though rapamycin and other related reagents have made great success. Taraxasterol (TAS) is an active ingredient of dandelion, an anti-inflammatory medicinal herb with low in vivo toxicity that has long been used in China. Yet the action mechanism of TAS on lymphocytes remains elusive. The anti-inflammatory effects of TAS were evaluated in C57BL/6 mouse primary lymphocytes stimulated with concanavalin A (Con A) in vitro and in mouse model of Con A-induced acute hepatitis in vivo. Our results showed that TAS significantly suppressed Con A-induced acute hepatitis in a mouse model, reducing the hepatic necrosis areas, the release of aminotransferases, and the production of IL-2 and other inflammatory cytokines. Supporting this, in vitro study also showed that TAS reduced the production of IL-2 and the expression of IL-2 receptor subunit α (CD25) upon the stimulation of Con A, which was likely mediated by suppressing NF-κB activation. The downstream pathways of IL-2/IL-2R signaling, including the activation of PI3K/PDK1/mTOR, STAT3 and STAT5, were also suppressed by TAS. Consistently, Con A-induced T cell proliferation was also inhibited by TAS in vitro. Our data indicate that TAS can suppress both T lymphocyte activation and cell proliferation by down-regulating IL-2 expression and its signaling pathway thereby ameliorating Con A-induced acute hepatitis, highlighting TAS as a potential drug candidate for treating inflammatory diseases including autoimmune hepatitis.

Gout-associated monosodium urate crystal-induced necrosis is independent of NLRP3 activity but can be suppressed by combined inhibitors for multiple signaling pathways.

Monosodium urate (MSU) crystals, the etiological agent of gout, are formed in joints and periarticular tissues due to long-lasting hyperuricemia. Although MSU crystal-triggered NLRP3 inflammasome activation and interleukin 1ß (IL-1ß) release are known to have key roles in gouty arthritis, recent studies revealed that MSU crystal-induced necrosis also plays a critical role in this process. However, it remains unknown what forms of necrosis have been induced and whether combined cell death inhibitors can block such necrosis. Here, we showed that MSU crystal-induced necrosis in murine macrophages was not dependent on NLRP3 inflammasome activation, as neither genetic deletion nor pharmacological blockade of the NLRP3 pathway inhibited the necrosis. Although many cell death pathways (such as ferroptosis and pyroptosis) inhibitors or reactive oxygen species inhibitors did not have any suppressive effects, necroptosis pathway inhibitors GSK'872 (RIPK3 inhibitor), and GW806742X (MLKL inhibitor) dose-dependently inhibited MSU crystal-induced necrosis. Moreover, a triple combination of GSK'872, GW806742X, and IDN-6556 (pan-caspase inhibitor) displayed enhanced inhibition of the necrosis, which was further fortified by the addition of MCC950 (NLRP3 inhibitor), suggesting that multiple cell death pathways might have been triggered by MSU crystals. Baicalin, a previously identified inhibitor of NLRP3, inhibited MSU crystal-induced inflammasome activation and suppressed the necrosis in macrophages. Besides, baicalin gavage significantly ameliorated MSU crystal-induced peritonitis in mice. Altogether, our data indicate that MSU crystals induce NLRP3-independent necrosis, which can be inhibited by combined inhibitors for multiple signaling pathways, highlighting a new avenue for the treatment of gouty arthritis.

Factors associated with psychological impact of celebrity suicide media coverage: An online survey study.

BACKGROUND: We investigated factors associated with vulnerability to the psychological impact of celebrity suicide news reporting after the suicide of an emerging Taiwanese novelist, Ms Yi-Han Lin. METHODS: We conducted a cross-sectional online survey. Participants completed a questionnaire which asked whether they were affected by the media coverage of Lin's suicide and whether they would seek help if affected. Logistic regression was used to identify factors associated with being affected by the celebrity suicide media reporting and, among those affected, factors associated with feeling suicidal or not seeking help. RESULTS: A total of 1258 respondents (81% females) completed the survey. Affected individuals (n=907; 70%) were more likely to be females, younger (age < 40 years), have past psychiatric treatment, and show increased interest in the incident (e.g., spending more time on reading the celebrity suicide news) than non-affected individuals. Among those affected, negative views of the media reporting impact, pessimistic attitude toward both depression treatment and suicide prevention, and having a history of past psychiatric treatment were associated with feeling suicidal, while low education attainment, increased interest in the celebrity suicide, and permissive attitude toward inappropriate media reporting were additionally associated with not seeking help. LIMITATIONS: Selection bias of participants through internet-based surveying should be considered. CONCLUSION: Individuals affected by the media coverage of celebrity suicide showed similar demographic and mental health characteristics as those of the deceased celebrity. Poor mental health and suicide prevention literacy may increase the risk of psychological impact and not seeking help. Future interventions could target at enhancing mental health literacy and help seeking intention in vulnerable individuals.

A three-component reaction of arynes, sodium sulfinates, and aldehydes toward 2-sulfonyl benzyl alcohol derivatives.

A novel three-component reaction of arynes, sodium sulfinates, and aldehydes under mild reaction conditions is described. This transformation provides a direct synthetic approach to 2-sulfonyl benzyl alcohol derivatives, which could be rapidly converted to diverse arylsulfur compounds via the transformation of the corresponding hydroxyl groups. Various aryne precursors, sodium arenesulfinates, and aromatic aldehydes can be effectively converted to the desired products in 40-84% yields (29 examples).

Direct Synthesis of ortho-Halogenated Arylphosphonates via a Three-Component Reaction Involving Arynes.

A three-component reaction involving arynes, trialkyl phosphites, and halides has been achieved under mild reaction conditions. This transformation provides a direct synthetic approach to ortho-halogenated arylphosphonates, which could be rapidly converted to diversely ortho-functionalized arylphosphorus compounds.

A phosphoryl radical-initiated Atherton-Todd-type reaction under open air.

A phosphoryl radical-initiated Atherton-Todd-type reaction using air as the radical initiator and CHCl3 as the halogenating reagent for the phosphorylation of alcohols, phenols, and amines has been developed. This novel transformation provides a highly efficient route to important phosphinates, phosphinic amides, and phosphoramidates in up to 99% yield with a broad substrate scope under very mild conditions (48 examples).

TBHP/NH4I-Mediated Direct N-H Phosphorylation of Imines and Imidates.

A direct and practical metal-free N-H phosphorylation has been achieved via the TBHP/NH4I-mediated cross-dehydrogenative coupling (CDC) reactions between imines/imidates and P(O)H compounds. This transformation provides an efficient synthetic route to the construction of P-N bonds with good functional group compatibility, leading to the formation of N-phosphorylimines and N-phosphorylimidates in up to 95% yield (33 examples) under mild conditions.

The effect of an anaesthetic patient information video on perioperative anxiety: A randomised study.

BACKGROUND: Despite growing evidence that an educational anaesthesia video can effectively reduce perioperative anxiety, the ideal medium for addressing perioperative anxiety is unclear. OBJECTIVE: The purpose of this study was to investigate the effect of viewing an anaesthetic patient information video on anxiety levels in patients scheduled to undergo surgery. DESIGN: A randomised controlled trial. SETTING: Pingtung Christian Hospital (PTCH), Taiwan. PATIENTS: One hundred patients were randomised to either an experimental group (n = 50) or a control group (n = 50). INTERVENTIONS: At the preoperative clinic, the experimental group watched the an 8 minute educational anaesthetic video, whereas the control group received a standard 8-min verbal briefing on anaesthesia after preoperative assessment. MAIN OUTCOMES MEASURES: The Chinese version of the Spielberger state trait anxiety inventory, which included a state scale (STAI-S) and a trait scale (STAI-T), was performed in the preoperative clinic (T1) before anaesthetic preassessment, at the preoperative holding area just before surgery (T2) and again on the third day after surgery (T3). Scores for overall satisfaction with medical care were obtained on the third day after surgery. For two time interval comparisons, effect size was used to standardise the extent of change as measured by STAI-S. RESULTS: After the educational intervention, state anxiety was lower in the experimental group than in the control group at both T2 (42.9 ±â€Š6.5 vs. 45.0 ±â€Š12.7) and T3 (40.2 ±â€Š5.3 vs. 48.8 ±â€Š8.5). Compared with control group, the experimental group had a larger effect size at T2 and T3 (-0.65 and -0.36, respectively). Overall satisfaction was significantly higher in the experimental group than in the control group (P < 0.05). CONCLUSION: Perioperative anxiety was significantly reduced and overall patient satisfaction increased after viewing a preoperative educational anaesthesia video compared with a standard verbal briefing on anaesthesia.

Comparisons of prediction models of myofascial pain control after dry needling: a prospective study.

Background. This study purposed to validate the use of artificial neural network (ANN) models for predicting myofascial pain control after dry needling and to compare the predictive capability of ANNs with that of support vector machine (SVM) and multiple linear regression (MLR). Methods. Totally 400 patients who have received dry needling treatments completed the Brief Pain Inventory (BPI) at baseline and at 1 year postoperatively. Results. Compared to the MLR and SVM models, the ANN model generally had smaller mean square error (MSE) and mean absolute percentage error (MAPE) values in the training dataset and testing dataset. Most ANN models had MAPE values ranging from 3.4% to 4.6% and most had high prediction accuracy. The global sensitivity analysis also showed that pretreatment BPI score was the best parameter for predicting pain after dry needling. Conclusion. Compared with the MLR and SVM models, the ANN model in this study was more accurate in predicting patient-reported BPI scores and had higher overall performance indices. Further studies of this model may consider the effect of a more detailed database that includes complications and clinical examination findings as well as more detailed outcome data.

Dry needling for myofascial pain: prognostic factors.

OBJECTIVES: The study objectives were to evaluate outcomes in patients who have received dry needling treatments and to identify predictors of pain and disability. DESIGN: The study was a prospective cohort follow-up design. SETTING: The study was conducted at the Pain Clinic at Pingtung Christian Hospital, Taiwan. SUBJECTS: Ninety-two (92) patients sick-listed for 3 months or longer for myofascial pain syndrome. INTERVENTIONS: From February to October 2008, participants were treated at the pain clinic with dry needling of trigger points and muscle stretches of the involved muscles. OUTCOME MEASURES: Data were collected by self-administered questionnaires to assess changes in pain intensity and pain interference. Data collection was performed at baseline and after 2, 4, and 8 weeks. Sociodemographic variables, symptom characteristics, and baseline outcome measures were analyzed using generalized estimating equation methodology. RESULTS: The proposed dry-needling protocol reduced pain intensity and pain interference. Long duration of pain symptoms, high pain intensity, poor quality of sleep, and repetitive stress were associated with poor outcomes. CONCLUSIONS: Dry needling is an effective treatment for reducing pain and pain interference. However, long pain duration, high pain intensity, poor quality of sleep, and repetitive stress are associated with poor outcomes. Treatment outcome depends not only on the dry needling protocol, but also on disease characteristics and patient demographic profile.

Educational program for myofascial pain syndrome.

OBJECTIVE: The objective of this study was to evaluate a program for managing myofascial pain syndrome (MPS). DESIGN: The study design was a randomized controlled trial. SETTING: The setting was the pain clinic of an academic hospital in Taiwan. PARTICIPANTS: Sixty-two (62) patients with a 3-month or longer history of MPS who were treated at this institution from July to November 2007 were included in the study. INTERVENTIONS: The participants were randomized to an experimental group (n = 32) or a control group (n = 30). Both groups underwent trigger-point dry needling and muscle-stretch exercise regimen for passively stretching the affected muscles to their normal lengths; the experimental group then watched an 8-minute multimedia instructional video about MPS with supplemental handouts. MAIN OUTCOME MEASURES: The Brief Pain Inventory-Taiwan was administered at baseline and 1 month thereafter. The effect size model was used to measure the effects of Brief Pain Inventory-Taiwan. Bootstrap estimation was used to derive 95% confidence intervals for group differences. RESULTS: Compared to the control group, the experimental group had significantly less interference of pain, lower intensity of present pain, and least pain (p < 0.05). Multiple regression analysis of patients with shoulder pain revealed significantly improved pain intensity and interference of pain (p < 0.05). CONCLUSIONS: The findings emphasize the importance of including patient education programs in MPS intervention.

Factors leading to self-extubation of endotracheal tubes in the intensive care unit.

AIM AND OBJECTIVE: To discuss the factors leading to self-extubation of endotracheal tubes (ETTs) and explore the differences between the groups of patients who did and did not self-remove their ETTs. BACKGROUND: Self-extubation of ETTs has been reported to occur in 4.2% of severely ill patients and is associated with adverse medical effects. DESIGN: A case-control study. METHODS: One hundred and thirty-nine subjects were recruited from a teaching hospital in southern Taiwan based on purposive sampling. The rate of self-extubation of ETTs was 6.4%. Analysis of the two groups demonstrated that significant variables were identified and fell into three categories: (1) the department to which the patient was admitted (p < 0.001), (2) whether the patient met the criteria for extubation (p < 0.001) and (3) the patient age (p < 0.05). Based on multiple logistic regression analysis, whether the patient met the criteria for extubation was a main variable that was associated with self-extubation of the ETT. Among the 44 patients who had self-extubation of their ETT, 28 met the criteria to be extubated, 70% and 81.8% of whom were not sedated, and self-extubation of their ETT was conscious of the act. Of the patients who attempted to self-remove their ETT, 80% were successful and 93.2% did not incur any adverse medical effects. CONCLUSION: The medical doctor and nurse should fully evaluate a patient's oxygenation status, decrease the length of the extubation training session for patients and extubate patients promptly when extubation criteria are met. RELEVANCE TO CLINICAL PRACTICE: Adopting a proactive approach to patient extubation will improve the overall quality of care.